BAM 11 (1) 2001
Reviews
5
Cardiomyoplasty:
to be
or not to be? Review and proposed multi-step approach for improving results
VS
Chekanov [Full
text pdf 49.3Kb]
Articles
13 Morphology
and Myosin
isoforms expression of regenerating innervated and denervated myotubes
of
tibialis cranialis muscles in
two strains of turkey (Meleagris
gallopavo)
S Bakou, Y Cherel, L Guigand, E Bandman and M
Wyers
[Full text pdf 181Kb]
23 Effects
of gonadectomy,
testosterone replacement and supplementation on cardiac action potentials in
the rat
G D'antona, MR Gualea and T
Ceriani [Full
text pdf 211Kb]
31 Effect
of quercetin
and DMSO on skeletal myogenesis from C2C12 skeletal muscle cells with special
reference
to
PKB/Akt activity, myogenin
and Bcl-2 expression
A Orzechowski, K Grzelkowska, W Karlik and T
Motyl [Full
text pdf 1.49Mb]
45 Porcine
satellite
cells from large and small siblings respond differently to
in vitro conditions
AK Clelland and NC
Stickland
[Full text pdf 149Kb]
Myology News
51
First National Meeting of the Italian Association of
Myology
Camogli-Genova (Italy), October 19-20,
2001 Abstracts
[Full text pdf 120Kb]
Cardiomyoplasty:
To Be or Not To Be? Review and Proposed Multi-Step Approach
for Improving
Results
Valeri S. Chekanov
Heart Care Associates,
Inc., Milwaukee
Heart Institute at Sinai Samaritan Medical Center, Milwaukee,
WHeart
transplantation is the best option for surgical treatment of
end-stage
congestive heart disease. However, when heart transplantation is
not possible,
other surgical options are available: partial left
ventriculectomy, assist
devices, plastic cardiac binding, cardiomyoplasty (CMP). All of
these operations
have advantages and disadvantages and at present there is no
consensus
as to which one is the best. Below is a new multistep approach
for improving
cardiomyoplasty
results according to our clinical and experimental data. In
order to decrease
the length of time and extent of damage of the CMP operation one
can use
a lateral approach to mobilize the LDM and wrap the heart. In
order to
build long-term fatigue resistance in the LDM of older patients
one can
increase the length of time of the preassist training of the LDM
using
a more cautious regimen. In order to improve hemodynamic results
after
muscle conditioning the cardiosynchronization regimen can be
changed from
1:2 to 1:4. In order to prolong the period of effective LDM
performance
the electrical stimulation may be switched off at night or
changed to a
rate of 1:8-1:16. New cardiomyostimulator LD-PACE II was
designed with
the capability to program a different regimen for day use than
for night
use. In order to prevent sudden cardiac death in the patient
with severe
cardiac arrhythmia it is possible to combine CMP with ICD
implantation.
In order to implement cardiac assist immediately after CMP it is
possible
to start with a cautious electrical stimulation regimen
(1:16-1:8) just
after CMP or to use cardiac assist (work-rest regimen) several
hours daily.
In order to prevent ischemia-reperfusion damage to the LDM after
subtotal
mobilization, the LDM can be treated with an application of
fibrin sealant
with added aprotinin. In order to accelerate both angiogenesis
and indirect
myocardial revascularization, fibrin sealant enhanced with
autologous endothelial
cells can be administrated between the LDM and the myocardium.
Key words:
cardiomyoplasty,
multi-step approach, work-rest regimen.
Morphology and Myosin Isoforms Expression of Regenerating Innervated and Denervated Myotubes of Tibialis Cranialis Muscles in Two Strains of Turkey (Meleagris Gallopavo)
S. Bakou, Y. Cherel, L. Guigand, E. Bandman(1) and M. Wyers
UMR 703 INRA/ENVN, Ecole Nationale Vétérinaire, Nantes Cedex, France, (1) Department of Food Science and Technology, University of California, Davis, California
Abstract
Effects of Gonadectomy, Testosterone Replacement and Supplementation on Cardiac Action Potentials in the Rat
Giuseppe D'Antona, Maria Rita Gualea and Teresina Ceriani
Institute of Human
Physiology,
University of Pavia, Pavia, Italy
Abstract
The aim of this study was to evaluate the electro-physiological alterations induced by gonadectomy, testosterone replacement and supplementation on cardiac action potentials (APs) in sexually mature male rats. Furthermore we studied the effects of testosterone deprivation and administration on total protein (TPC) and sialic acid content (SAC) of the left ventricle. Four groups of rats were compared: control (C), gonadectomized (GD), GD replaced with testosterone propionate (5 mg/kg i.m. 6 days/week for 4 weeks, GDTP) and testosterone supplemented rats (TP 5 mg/kg i.m. 6 days/week for 4 weeks). The APs recorded from GD rats both in vitro on right ventricle papillary muscles, at various stimulation rates, and in situ in subepicardial cells, at spontaneous heart rate, showed a significant lengthening of action potential duration (APD) measured at 10% (APD10) and 50% (APD50) of repolarization in comparison with TP, GDTP and C. A significant lengthening of the finale phase of relaxation (APD95) was found also in TP rats. GD rats also showed a significant decrease in SAC. Testosterone replacement prevented both AP lengthening and SAC loss, whereas testosterone overload was associated only with a slight not significant increase of SAC. The rate at which ventricular fibrillation arises were determined and found to be lowered in both GD and TP groups when compared with C and GDTP rats. In conclusion, optimal testosterone serum level may contribute in the maintenance of normal myocardial electrogenesis and this may be partially attributed to regulation of the glycoprotein synthesis of glycocalyx.
Key words: action potential, androgens, glycocalyx, heart potential, sialic acid.
Effect of Quercetin and DMSO on Skeletal Myogenesis from C2C12 Skeletal Muscle Cells with Special Reference to PKB/Akt Activity, Myogenin and Bcl-2 Expression
Arkadiusz Orzechowski(1),
Katarzyna
Grzelkowska, Wojciech Karlik and Tomasz Motyl
(1) Department of Physiology,
Biochemistry,
Pharmacology and Toxicology, Faculty of Veterinary Medicine,
Warsaw Agricultural
University, Warsaw, Poland
Abstract
Conflicting data regarding the
effect
of antioxidants on skeletal myogenesis prompted us to study the
action
of superoxide anion and hydroxyl radical scavengers on
differentiating
murine C2C12 myoblasts. The onset of myotube formation was
delayed by quercetin
and DMSO while DNA synthesis was stimulated in response to
elevated doses
of both factors. Cell viability measured by MTT assay was
inhibited either
by 100 mM quercetin or 1% or 2% of DMSO whereas elevated number
of apoptotic
cells was detected at the same time. Muscle cell differentiation
retarded
by quercetin or DMSO was reflected by delay in myogenin
expression and
lowered distribution of myotubes with low (< 10) number of
cell myonuclei.
For large myotubes (> 10) low scores for DMSO, and high
scores for quercetin
were observed. Based on phosphorylation status, both
antioxidants delayed
PKB activation and PKB-dependent differentiation, as well as
antiapoptotic
effect of PKB. Bcl-2 antiapoptotic protein level was elevated
earlier for
control than for experimental treatment. Muscle creatine kinase
activity
reflected the reduced rate of myogenesis. In conclusion,
promitogenic activity
of quercetin and DMSO disturbs differentiation programme of
myoblasts and
might explain why more apoptotic cells was found after high
doses of both
factors. In contrast to DMSO, quercetin-induced delay in
myogenesis may
result in larger muscle mass. Results of this study support the
idea that
muscle differentiation can be regulated by scavengers of
superoxide anion
and hydroxyl radical.
Key words: antioxidants,
apoptosis, Bcl-2, muscle differentiation, myogenin, PKB.
Porcine Satellite Cells from Large and Small Siblings Respond Differently to In Vitro Conditions
Allyson K. Clelland and Neil C. Stickland
Department of Veterinary
Basic
Sciences, The Royal Veterinary College, University of London,
Camden, London,
U.K.
Abstract
In order to detect the effects
of
intra-uterine variation on the performance of neonatal satellite
cells,
the following experimental model was devised. Satellite cells
were removed
from the m. semitendinosus of the largest and smallest siblings
in six
litters of pigs and cultured under standardised, high glucose,
conditions
to reach approximately 85% confluence.
As the smallest piglet in a
litter
generally has a decreased growth rate in comparison to its
larger littermates,
it was expected that satellite cells derived from these piglets
would also
perform at a lower level. This was not found; satellite cells
from small
siblings proliferated at a significantly higher level than from
larger
siblings in all trials.
This result implies that,
instead
of the satellite cells being detrimentally affected by early
developmental
events, they are in fact primed to react positively to any
additional nutrition
present in the surrounding environment.
Key words: intra-uterine
variation, growth rate, porcine, satellite cells.
First
National Meeting
of the
Italian
Association of Myology
Camogli-Genova (Italy)
October 19-20, 2001
ABSTRACTS
The clinical spectrum of
dysferlinopathies
S. Alfieri, MF. Bellanova, *A.
Scaglioni,
G. Melli, C. Inglese, F. Gemignani and A. Marbini
Istituto di Neurologia
Università
di Parma, and *Neurologia Azienda USL Parma- Ospedale di Fidenza
Mutations in the dysferlin gene
(2p13) have been recently identified as responsible for an
autosomal recessive
form of limb-girdle muscular dystrophy (LGMD), classified as
LGMD2B. We
describe three patients with dysferlinopathy showing different
phenotypes.
Two siblings, aged 24 and 21,
had
severe weakness and wasting in the muscles of the pelvic girdle
and, to
a lesser extent, of the shoulder girdle, and waddling gait. A
26-year-old
woman had progressive difficulty walking by age 20. Examination
showed
severe weakness and wasting of the lower limbs with distal
predominance,
and mild weakness in the upper limbs with pseudohypertrophy of
the deltoid
muscles. Muscle biopsy showed, in all patients, dystrophic
changes. Immunohistochemical
labelling for dysferlin on frozen sections and Western blot
analysis showed
absence of dysferlin band. Genetic studies for the
identification of the
mutation(s) are in progress.
At least 14 LGMD genes have
been
mapped, including both autosomal dominant and autosomal
recessive forms.
On the other hand, discordant phenotypes may be seen in patients
carrying
the same mutation, even among affected siblings. Mutations in
the dysferlin
gene may manifest with mainly distal involvement (Miyoshi
myopathy), or
with classical clinical features of LGMD. Future knowledge of
gene-protein
function and protein interactions, and of modifying genes, will
better
clarify genotype-phenotype correlations in LGMD.
LONG TERM TREATMENT WITH ALBUTEROL IN JUVENILE AND ADULT ACID MALTASE DEFICIENCY PATIENTS
Corrado Angelini, Maria Cristina Mantovan, Elena Pegoraro
Regional Neuromuscular Center, University of Padova, Department of Neurological and Psychiatric Sciences
Acid maltase deficiency (AMD)
is
a prototypical lysosomal disorder that can present as infantile,
juvenile
or adult onset. Acid a glucosidase replacement was so far tried
only in
infantile cases but is not feasible in adult patients. Since 3
years we
performed an open prospective clinical trial with a b2 agonist
(albuterol)
and interni Heart pulsed chain aminoacids. In our trial we
included five
adult onset ambulant women (age 56-69 years) and a juvenile
onset 56 year
old man (disease duration: 30 years), who was wheelchair bound
and respirator
dependent. The rationale of treatment is that b2 agonists
antagonise muscle
wasting and increase muscle mass and strength. A protocol was
designed
to follow these patients by functional tests and spirometry. We
followed
the patients every 3 months initially and then every 6 months
evaluating
five muscles by MRC scale. We also timed and monitored the
performances
of four functions (walking, climbing stairs, Gowers’
and rising
from a chair).
Our patients tolerated well 6-8
mg oral albuterol for this period and their strength and
clinical performances
appear stabilized after 3 years.
Our data suggest that in adult
glycogen
storage type 2 the use of oral b2 agonists might be useful.
ULLRICH SCLEROATONIC MUSCULAR DYSTROPHY IS CAUSED BY RECESSIVE MUTATIONS IN COLLAGEN TYPE VI
E. Bertini1, O. Camacho Vanegas2, R. Zhang3, S. Petrini1, P. Sabatelli4, B. Giusti5, M. Chu3, N. Maraldi4, S. Squarzoni4, L. Merlini4, G. Pepe2
1Unit of Molecular Medicine, “Bambino Gesù Hospital, IRCCS”, Rome, Italy; 2University of Rome “Tor Vergata”, 3Thomas Jefferson University, Philadelphia, Pennsylvania, U.S.A, 4Institute of Normal and Pathological Cytomorphology, CNR c/o IOR, Bologna, Italy; 5University of Florence, Italy.
Ullrich congenital muscular dystrophy (UCMD) is a recessive CMD affecting connective tissue and muscle. Reverse-transcription PCR amplification of RNA extracted from fibroblasts or muscle of three UCMD patients, followed by heteroduplex analysis, displayed heteroduplexes in one of the three genes coding for collagen type VI (COL6). In patient-A we detected a homozygous insertion of a C leading to a premature termination codon in the triple-helical domain of COL6A2 mRNA. Both consanguineous parents were healthy carriers. In patient-B, and in the affected brother, we found a deletion of 28 nucleotides due to an A->G substitution at nucleotide -2 of intron 17 causing the activation of a cryptic acceptor site inside exon 18. The second mutation was an exon skipping due to a G->A substitution at nucleotide -1 of intron 23. The healthy mother carries the first mutation, while the second mutation is carried by their healthy father. In patient-C we found only one mutation so far, the same deletion of 28 nts found in patient-B, a ‘de novo’ mutation, absent in her parents. mRNA and protein analysis of patient B showed a very low amount of COL6A2 mRNA and of COL6. Severe defect of COL6 was demonstrated by immunofluorescence in fibroblasts and muscle. Our results demonstrate that UCMD is caused by recessive mutations leading to a severe reduction of COL6.
NON PROGRESSIvE Xp21 BECKER MUSCULAR DYSTROPHY IN THE EIGHTH DECADE
Simona Bortolotto, Carlo Doriguzzi*, Ivana Bosone, Loredana Chiadò-Piat, Isabella Ugo, Cristina Borghese, Roberto Mutani, Tiziana Mongini, Laura Palmucci
Dipartimento di Neuroscienze, Centro per le Malattie Neuromuscolari P Peirolo, Università di Torino; *Divisione di Neurologia, Ospedale E.Agnelli, Pinerolo
A 60-year old man was referred
to
us in 1987 complaining of difficulty walking and climbing stairs
developed
over the previous 10 years. Clinical examination disclosed
waddling gait,
Gower’s sign, calves hypertrophy and proximal wasting
and weakness,
prevalent in the lower limbs. Serum creatine kinase levels were
increased
(200 U/l), EMG showed myopathic alterations. Quadriceps muscle
biopsy was
performed. Routine staining showed fibre size variability, fibre
degeneration
and increase of connective tissue. Monoclonal antibodies against
dystrophin
showed regular, continuous but pale contours. Western blot
demonstrated
reduced molecular weight of dystrophin (370 Kd). Genetic
analysis detected
a deletion of the exons 45-53 in the Xp21 gene.
Fourteen years’
follow
up did not show significant impairment of muscle strength or
development
of cardiac alterations. At the age of 74, the patient can still
walk unassisted.
The case underlines the
importance
of the study of dystrophin in all the myopathies of uncertain
definition
also in elderly patients.
VERY LATE ONSET AND MILD EXPRESSION IN TYPE II GLYCOGENOSIS
Ivana Bosone, Tiziana Mongini, Simona Bortolotto, Loredana Chiadò-Piat, Isabella Ugo, Cristina Borghese, Roberto Mutani, Laura Palmucci
Dipartimento di Neuroscienze, Centro per le Malattie Neuromuscolari P Peirolo, Università di Torino
Type 2 glycogenosis is an
autosomal
recessive disorder due to deficiency of the lysosomal enzyme
acid maltase.
The clinical spectrum includes infantile, childhood and adult
variants.
These latter usually have their onset in the third or fourth
decade. Few
cases with later onset have been described. The oldest case in
the literature
is a 65-year-old man.
We observed a 74-year-old woman
with a two years’ history of easy fatigability,
proximal weakness
in her lower girdle. Neurological examination showed waddling
gait, lumbar
hyperlordosis, Gowers’ sign, and pelvic girdle
weakness with
normal strength of the upper limbs. Serum CK was 400 U/l.
Echocardiography,
Holter-ECG and spirometry were normal. Muscle biopsy disclosed a
vacuolar
myopathy with intralysosomal glycogen storage. Biochemical
analysis showed
increased glycogen and marked reduction of acid maltase activity
(10% of
residual activity). A cerebral spiral CT scan did not
demonstrate intracranial
aneurysms.
The case is interesting for the
mild clinical phenotype, limited to weakness of the pelvic
girdle muscles
and without involvement of the respiratory muscles, which are
typically
affected in the adult form. To our knowledge this is the patient
with the
latest onset reported in the literature and it emphasizes the
importance
of considering the possibility of a metabolic myopathy even in
elderly
patients with neuromuscular disorders.
Acute quadriplegic myopathy
(AQM):
clues from an in vitro model
Aldobrando Broccolini, Adele
D’Amico,
Simone Di Giovanni, Massimiliano Mirabella, Manuela Papacci,
Gabriella
Silvestri, Serenella Servidei
Institute of Neurology,
Catholic
University, Rome
AQM is often associated with
corticosteroid
therapy and neuroblocking agents, metabolic impairment, sepsis,
intensive
care and surgery. The morphological hallmarks of AQM are muscle
fibers
atrophy and thick filaments loss. We have previously shown that
apoptosis
plays a role in AQM pathogenesis.
As an in vitro model of AQM,
normal
aneural primary muscle cultures were exposed to 300 mM mannitol,
as a metabolic
stressor, and 100 microM dexamethasone and then studied with
TUNEL, to
detect nuclear DNA fragmentation, and immunocytochemistry for
caspase 3,
Bax and calpain.
Treatment with mannitol or
dexamethasone
alone induced none or only minor morphological abnormalities,
while combined
dexamethasone and mannitol resulted in swelling and
fragmentation of myotubes.
No TUNEL positive myonuclei were found in control and
dexamethasone treated
cultures, while only a small proportion was found in
mannitol-treated ones.
In contrast, combined dexamethasone and mannitol produced a high
number
of TUNEL positive myonuclei and increased staining for caspase
3, Bax and
calpain.
Our results confirm a possible
role
of apoptosis in the pathogenesis of AQM and suggest that i)
dexamethasone
highly potentiates metabolic stress-induced apoptosis, possibly
by inhibiting
the IGF-I anti-apoptotic pathway, and ii) the activation of
proteolytic
pathways contributes to muscle fiber degeneration.
SCREENING OF
EXPANDED CTG
REPEATS ON CHROMOSOME 19 FOR MYOTONIC DYSTROPHY
TYPE 1 (DM1) IN 618 ITALIAN
PATIENTS
AND THEIR RELATIVES, AND 10 CASES OF PRENATAL DIAGNOSIS
R. Brugnoni, L. Morandi, F. Cornelio, R. Mantegazza
Department of Neuromuscular Diseases, National Neurological Institute “C. Besta”, via Celoria 11, 20133 Milan, Italy, Phone: (39) 02-2394371, Fax: (39) 02-70633874, E-mail: rbrugnoni@istituto-besta.it
Myotonic dystrophy type 1
(DM1) is
an autosomal dominant neuromuscular disease and is the most
common form
of muscular dystrophy affecting adults. An unstable,
untranslated part
of the DMPK gene on chromosome 19, composed of CTG repeats, is a
genetic
marker for DM1. Normal individuals have 5 to 50 CTG repeats,
mildly affected
or asymptomatic DM patients have 50 to 180 repeats, while fully
affected
patients have from over 200 to 2000 repeats (range E1=50-500,
E2=500-1000
and E3>1000 CTG).
To detect CTG expansion we used
a procedure based on a PCR amplification using XL polymerase
followed by
Southern blot analysis with a fluorescein-labelled (CTG)10
probe. We studied
618 Italian patients and their relatives [302 males and 316
females]. We
identified CTG expansion in 321 DM patients (51.9%) [among these
54 (16.8%)
with range E1, 251 (78.2%) with range E2 and 16 (5%) with range
E3] and
the normal alleles in 297 subjects (48.1%).
Among 119 analysed families 28
showed
the phenomenon of anticipation and 6 showed the
intergenerational contraction
in PBL, whit 100% of maternal transmission and 83.3% of paternal
transmission,
respectively.
This technique was also used
for
prenatal diagnosis on genomic DNA extracted from 10 chorionic
villi of
7 females. CTG expansions were in range E1 for 1 fetus, E2 for 4
fetuses
and E3 for 3 fetuses, while two fetuses were normal even if the
mothers
had CTG expansion in range E2.
Myoglobinuria triggered by
Convulsions
in Mcardle’s disease
Claudio Bruno1, Roberta
Lanzillo2,
Anna Orsini2, Lucia Iadicicco2, Carlo Minetti1, Salvatore
DiMauro3, Lucio
Santoro2
1Lab. di Patologia Muscolare,
Università
di Genova, Istituto G. Gaslini, Genova, Italy, 2Dip. di Scienze
Neurologiche,
Università di Napoli «Federico II», Napoli, Italy and
3Dept. of Neurology, Columbia University, New York, U.S.A.
Human myophosphorylase
deficiency
(McArdle’s disease; Glycogenosis type V) is one of the
most common
muscle glycogenoses. It is typically a disease of young adults
characterized
by exercise intolerance, myalgia, cramps, and recurrent
myoglobinuria.
The diagnosis is confirmed by histochemical and/or biochemical
documentation
of phosphorylase deficiency in muscle biopsy or by molecular
analysis of
the myophosphorylase gene (PYGM) of blood cells. Although the
clinical
phenotype is rather uniform, different clinical variants both in
infancy,
childhood, and adulthood have been reported.
We report a 11-year-old girl in
whom, starting age 8 and in several occasions, muscle necrosis
with myoglobinuria
were preceded by convulsions or exercise. Neurological
examination was
normal. A muscle biopsy was obtained from the left quadriceps,
and histochemical
reactions were performed by described methods. Genomic DNA was
extracted
from white blood cells of the patients and her parents.
Histochemical analysis
of muscle showed myophosphorylase deficiency and genetic
analysis of PYGM
gene showed that the patient was homozygous for the most common
mutation
encountered in McArdle’s disease (R49X), while her
parents were
heterozygous.
Our case further illustrates
the
atypical clinical presentation of McArdle’s disease
and confirm
the lack of genotype/phenotype correlation in this disease.
Subclinical inflammatory
myopathy
in chronic hepatitis b virus infection
M. Capasso*, A. Di Muzio*, S.
Lupo*,
K. Falasca#, E. Pizzigallo#, A. Uncini*
*Centro per le Malattie
Neuromuscolari
e #Clinica delle Malattie Infettive, Università
“G.d’Annunzio”,
Chieti.
An inflammatory myopathy may be
associated with different viral illness but muscle fibres are
reported
to be resistant to direct viral infection. Up to now a
clinically evident
mystic has been reported in 7 patients with hepatitis B virus
(HBV) infection.
The immunofluorescence for HBV was performed on muscle biopsy in
only one
case with negative result.
We report two patients with
chronic
active HBV hepatitis, persistent hyperckemia (3-10 X normal) and
no weakness.
Other causes of asymptomatic hyperckemia were excluded. The EMG
was myopathic
in both patients with mild spontaneous activity in one. Muscle
biopsy showed
moderate muscle fibres size variability, necrotic fibres,
scattered endomysial
CD4+, CD68+ and rare CD8+ cells. Deposits of complement membrane
attack
complex (MAC) were present in blood vessels walls and in some
necrotic
muscle fibres. Immunoperoxidase showed positivity of the HBV
core antigen
in some infiltrating cells and, in one patient, in a few
necrotic muscle
fibres. At follow up (at least one year) both patients had still
active
hepatitis and increased CK but did not develop weakness.
We deem that these patients
have
a subclinical inflammatory myopathy associated with HBV
infection. Our
immunohistochemical findings may suggest a direct role of HBV in
associated
myositis.
ASYMPTOMATIC HYPERCKEMIA: THE ROLE OF QUANTITATIVE emg
M. Capasso, A. Di Muzio, M.V. De Angelis, A. Uncini.
Centro per le Malattie Neuromuscolari, Università “G. d’Annunzio”, Chieti.
With the inclusion of CK
determination
in the automated blood chemistry profile an increasing number of
patients
with apparently unexplained rised CK are referred to
neuromuscular clinics.
The main problem is how much extensive investigations should be
performed
to rule out a subclinical neuromuscular disorder.
In the four largest (at least
10
patients) series with asymptomatic iperCKemia qualitative EMG
was abnormal
in percentages variable from 28 to 78 % and the concordance with
histopathology
extremely variable.
In 18 subjects with
asymptomatic
iperCKemia we performed quantitative EMG and muscle biopsy in
the contralateral
muscles. Quantitative EMG showed reduced mean value of MUAP
duration in
6 and increased percentage of polyphasics in 9 patients. Muscle
biopsy
indicated a specific disorder in 5 patients: 2 had inflammatory
myopathy,
1 dystrophinopathy, 1 glycogen storage disease type II, 1
mitochondrial
myopathy. One patient had myoadenilate deaminase deficiency and
five others
showed minor non specific myopathic features. Quantitative EMG
was highly
specific being normal in all patients with normal biopsy, and
highly concordant
with histopathological findings being normal only in the patient
with asymptomatic
acid maltase deficiency.
In conclusion in presence of a
normal
quantitative EMG it may be wise to refrain from extensive
ancillary test
as long as the patient do not have complaints or develop
neurological abnormalities.
CARDIAC INVOLVEMENT IN AUTOSOMAL DOMINANT MYOTUBULAR/CENTRONUCLEAR MYOPATHY
M. Damiano1, F.Ventriglia2, A. Celato1, G.D’Amati3, A. Kraus1, V. Colloridi2, G.A.Amabile1, C.Casali1
1Istituto di Clinica delle Malattie Nervose e Mentali, 2Cattedra di Cardiologia Pediatrica, Istituto di Clinica Pediatrica; 3Dipartimento di Medicina Sperimentale, Università di Roma, La Sapienza, Rome, Italy.
We studied a 23-year-old man and his 43-year-old father with proximal muscle weakness, onset in childhood and slowly progressive course. Elevated CK levels and a myogenic EMG pattern were found. Muscle biopsy showed increased variability in fibre size, type 1 fibre predominance and many central nuclei. At the ATPase stains, many of the fibres contained a central zone of non-reactivity, corresponding to the nucleus. These findings suggested a diagnosis Autosomal Dominant Centronuclear/Myotubular Myopathy. The echocardiographic study showed dilated hypocinetic myocardium ranging from severe in the father to mild in the son. Centronuclear/Myotubular Myopathy is an example of genetic heterogeneity: autosomal-dominant with adult onset; autosomal recessive with childhood onset, and the most common X-linked recessive. The autosomal dominant form has a later onset and milder course than the X linked form, and the autosomal recessive form is intermediate in both respects. Cardiac involvement is extremely rare, even in the X-linked recessive form. The occurrence of dilatative cardiomyopathy in our patients, regardless the differences in the age at the diagnosis and the different general conditions such as ventilatory capacity, suggests a primary involvement of the cardiac muscle.
Adenovirus-mediated utrophin
gene
transfer mitigates the dystrophic phenotype of canine X-linked
muscular
dystrophy (CXMD)
Massimiliano Cerletti, Tiziana
Negri,
Francesca Cozzi, Ferdinando Cornelio, *Ottaviano Pozza, ^George
Karpati,
and Marina Mora
Department of Neuromuscular
Diseases,
Istituto Nazionale Neurologico “C. Besta”,
Milano,
Italy, *Istituto di Patologia Speciale e Clinica Medica
Veterinaria, Faculty
of Veterinary Medicine, University of Milano, Milano, Italy,and
^Montreal
Neurological Institute, McGill University, Montreal, Canada
We injected tibialis anterior
muscles
of newborn CXMD dogs with an adenoviral vector containing
truncated utrophin
(AdVCMV-Utr) and examined utrophin expression by RNA and protein
analysis
in cyclosporin treated and untreated animals. We also evaluated
extent
of fibrosis and expression of dystrophin-associated proteins
(DAPs) as
measures of the functional efficacy of gene transfer. In
cyclosporin-immunosuppressed
animals, 10, 30 and 60 days after treatment, intensely utrophin
positive
(transfected) fibers were found in variable size clusters. The
average
proportions of positive fibers were 28.3% at 30 days and 30.3%
at 60 days.
In animals not cyclosporin treated only scattered transfected
fibers were
found.
The presence of the shortened
utrophin
was confirmed by immunoblot. mRNA-PCR analysis of injected
muscles revealed
the expected 136 bp band of the truncated utrophin in
cyclosporin-treated
and untreated animals. This band was absent from uninjected
dystrophic
dogs.
DAP expression was greater in
transgenic
utrophin-positive areas and these areas were characterized by
polygonal-shaped
fibers and significantly less fibrosis (p<0.0001) than areas
not expressing
the exogenous protein.
Transgenic utrophin is
expressed
at the extrajunctional membrane of CXMD muscle fibers after
AdV-mediated
gene transfer, with stable expression for at least 60 days in
immunosuppressed
animals and efficiently mitigates the dystrophic phenotype.
A EMG study of myotonic and
dystrophic
phenomena in Steinert disease
C. Chisari, C. Simonella, R.
Licitra,
B. Rossi
Unit of Neurorehabilitation,
Dept.
of Neuroscience, University of Pisa, e-mail
c.chisari@mail.ao-pisa.toscana.it
The phenotypic expression of
myotonia
and dystrophy is variously combined in patients with Steinert
disease (MyD).
This represents a difficulty when evaluating the extent to which
each one
contributes to muscle function impairment and when studying the
physiopathological
processes underlying the disorder.
The aim of this study was to
apply
the surface EMG technique, using low and high stimulation
frequencies and
analyzing an amplitude parameter, in order to fully corroborate
the contribution
of myotonia and/or dystrophy to muscle impairment in MyD
subjects.
Methods: a motor point
stimulation
protocol, at 15 and 35 Hz, was carried out on the tibialis
anterior (TA)
of 25 MyD patients. These were subdivided into 3 subgroups, MyD3
(9), MyD4
(10) and MyD5 (6), on the basis of their TA MRC score. The
surface myoelectric
signal was recorded and the average rectified value of amplitude
(ARV)
was evaluated.
Results: each subgroup
presented
a characteristic ARV trend both at 15 and 35 Hz: increasing in
MyD3 (like
the controls), slightly decreasing in MyD4 and clearly
decreasing in MyD5.
Conclusions: the analysis of
the
ARV during a stimulated contraction permits the identification
and quantification
of the sarcolemma excitability alteration and/or the myofiber
degeneration
contributing to muscle impairment in MyD.
Immunological dysferlin
screening
in a large population of myopathic patients
Luca Chiveri1, Lucia Tancredi1,
Giacomo P Comi1, Monica Sciacco1, Patrizia Ciscato1, Massimo
Serafini1,
Gigliola Fagiolari1, Mauro Porta2, Guido Cavaletti3, Franco
Fortunato1,
Guglielmo Scarlato1, Maurizio Moggio1, Alessandro Prelle1
1Centro Dino Ferrari, Dpt di
Scienze
Neurologiche, Università di Milano, Ospedale
Maggiore-Policlinico
IRCCS, Via F. Sforza 35, Milan, Italy, 2Department of Neurology,
Pain Centre,
Policlinico San Marco, Corso Europa 7 24040 Zingonia-Bergamo,
Italy, and
3Clinica Neurologica, Università di Milano Bicocca, Ospedale S.
Gerardo, v. Donizetti 106, 20052 Monza, Italy
Recently, a novel mammalian
gene
has been discovered, whose mutations cause two different
myopathies: Limb
Girdle Muscular Dystrophy (LGMD) type 2B and distal Miyoshi
myopathy (MM).
The gene product is a 230 kDa sarcolemmal protein called
dysferlin, normally
expressed at skeletal muscle level and absent in affected
patients.
We analysed muscle biopsies
from
151 patients with myopathy and/or hyperCKemia, myopathic EMG,
normal muscle
expression of dystrophin, sarcoglycans and, in tested patients,
calpain,
merosin, emerin and caveolin.
By immunohistochemistry,
complete
dysferlin deficiency was found in 4 patients. Western blot (WB)
analysis
confirmed protein absence in three patients, whereas residual
protein amount
was present in the fourth one. Clinically, one had limb-girdle
myopathy,
two distal myopathy and one paucisymptomatic hyperCkemia. Muscle
biopsy
was dystrophic in the myopathies and mildly unspecific in the
hyperCkemia.
Perivascular infiltrates were present in one dystrophic biopsy.
In another
case, partial calpain deficiency was evident at WB. Apoptotic
studies in
two muscle biopsies showed scattered positive nuclei with TUNEL
reaction.
Dysferlin deficiency was found
in
2.6% of the screened population. This percentage is much higher
(28.6%)
if distal myopathy alone is considered, and lower if the
restriction regards
limb-girdle myopathy (1.7%) or paucisymptomatic hyperCkemia
(1.2%).
Riboflavin-responsive myopathy
with
multiple acyl Coenyme A (CoA) dehydrogenase deficiency (RR-MAD):
a case
report
Adele D’Amico, Simone
Di Giovanni, Massimiliano Mirabella, Aldobrando Broccolini, Anna
Modoni,
Lodovica Vergani*, Pietro Tonali, Serenella Servidei
Institute of Neurology,
Catholic
University, Rome and *Department of Neurological Sciences,
University of
Padova, Padova.
Adult onset RR-MAD is a rarely
recognized
disorder characterized by progressive limb and axial muscles
weakness,
lipid storage myopathy and responsiveness to riboflavin
supplementation.
Riboflavin is the precursor for flavin mononucleotide (FMN) and
flavin
adenine dinucleotide (FAD), both being prosthetic groups of
various mitochondrial
enzymes.
A 55-year old man presented
with
a progressive proximal muscle weakness, severe fatigability,
muscle pain,
persistent diarrhoea and weight loss. Laboratory findings showed
elevated
CK, normal thyroid function, no evidence of malabsorption and
absence of
urinary organic acids. EMG was myopathic with mild neurogenic
signs. Muscle
morphology showed increased lipids and ragged-red fibers.
Reduced activities
of medium- (27%) and long-chain acyl CoA dehydrogenases ( 56%)
and of complex
II ( 58%) with secondary carnitine deficiency were found. Muscle
FAD and
FMN were 46% and 20% of normal. Clinical symptoms did not
respond to steroids
or carnitine, but resolved promptly with riboflavin 100
mg/daily. Although
riboflavin deficiency may result from malabsorption, in our
patient diarrhoea
resolved after riboflavin supplementation. Hence, we propose
that diarrhoea
is also due to riboflavin deficiency.
Thus, a diagnosis of RR-MAD
should
be considered in patients affected by a proximal myopathy
associated with
gastrointestinal symptoms, in view of the possible successful
treatment.
Nonsense mutation in the LAMA2
gene
resulting in exon skipping and mild muscular dystrophy
Claudia Di Blasi1, Lucia
Morandi1,
Ferdinando Cornelio1, Pascale Guicheney2, and Marina Mora1
1Dept. of Neuromuscular
Diseases,
Istituto Nazionale Neurologico “C. Besta”,
Milano,
Italy, and 2Unité INSERM U523, Institut de Myologie, IFR
“Coeur,
Muscle et Vaisseaux” N.14, Groupe Hospitalier
Pitié-Salpêtrière,
Paris, France
Exon skipping is a mutational
mechanism
usually caused by changes in consensus sequences at splice sites
or lariat
branch-point regions. Nonsense mutations outside the splicing
consensus
sequence have been reported to cause skipping of the
nonsense-containing
exon in several human diseases. We describe, for the first time,
nonsense-mediated
exon skipping in the LAMA2 gene. Two adult siblings from a
consanguineous
family had a slight reduction in laminin ?2 chain expression and
moderate
clinical manifestations. In both, molecular analysis revealed a
homozygous
nonsense mutation, Arg744Stop, expected to result in a totally
non-functional
protein and a severe phenotype. Analysis of the transcript
revealed skipping
of exon 15, containing the mutation, although the consensus
sequences for
splicing at both ends of the exon and beginning of intron 15
were unaltered.
Exon skipping restored the open reading frame of the mutant
transcript
and resulted in a truncated protein. Our data confirm the
importance of
mRNA analysis to clarify the effect of mutations on mRNA
processing, which
may be different to that predicted by genomic analysis, and also
point
to the necessity of immunochemical screening for expression of
the laminin
a2 chain in atypical dystrophic adults as well as children.
AUTONOMIC NERVOUS SYSTEM FUNCTION IN MYOTONIC DYSTROPHY
R. Di Leo1, A. Papalia1, C. De Gregorio2, S. Coglitore2, C. Rodolico1, C. Nicolosi1, S. Sinicropi1, A.Toscano1, G. Annesi3, C. Messina1, G. Vita1.
1Department of Neurosciences, Psychiatry and Anaesthesiology, Policlinico Universitario, Messina- Italy ; 2 Unit of Cardiology, Policlinico Universitario, Messina- Italy; IMSEB CNR, Cosenza-Italy
To investigate the Autonomic
Nervous
System (ANS) in patients with Myotonic Dystrophy (MD). 23 MD
patients,
without severe heart involvement or diabetes, underwent a
battery of six
cardiovascular reflex tests, PSA of heart rate,
electroneurography, spyrometry
(FVC) and heart examination. 20 sex and age-matched healthy
subjects were
also investigated. All cardiovascular reflex tests were normal
in 35% of
the patients. 61 % had a borderline ANS dysfunction and 4% had a
definite
ANS dysfunction with two abnormal tests. The most frequently
altered tests
were the 30/15 ratio and beat to beat variation during deep
breathing (DB)
(26% and 26% respectively). The mean value of each test recorded
in MD
patients was not significant different from controls, except for
DB, in
which it was significantly lower in MD (p < 0.0001). Low
frequency power
resulted significantly lower in MD (p < 0.03). Nerve
conduction velocity
study was altered only in two consanguineous patients. FVC was
impaired
in 50 % of the patients, without any correlation to DB. There
was no correlation
between presence of heart abnormalities (48%) and ANS
dysfunction. Cardiovascular
tests, PSA, electroneurography and respiratory function were non
related
to CTG repeat size.
According with previous studies
autonomic dysfunction is not a major feature in MD, without
relationship
to heart involvement or presence of a peripheral neuropathy.
HEPATITIS C VIRUS (HCV) INFECTION AND MYOSITIS: VIRUS LOCALIZATION AND POSSIBLE IMMUNOPATHOGENESIS
Di Muzio*, B. Bonetti^, M.
Capasso*, S. Lupo*, E. Pizzigallo#, N. Rizzuto^, A. Uncini*
*Centro per le Malattie Neuromusculari e #Clinica delle Malattie Infettive Università “G. d’Annunzio” Chieti, ^Dipartimento di Scienze Neurologiche e della Visione, Università di Verona.
HCV in addition to the liver,
may
affect other organs and tissues. Although a direct viral
pathogenesis has
been hypothesized for liver and kidney, some complications are
probably
related to the secondary production of autoantibodies and
immunocomplexes.
An inflammatory myopathy has been rarely reported and poorly
documented.
We describe a patient with chronic active HCV infection without
cryoglobulins
who developed an inflammatory myopathy.
Muscle biopsy showed
perifascicular
atrophy, necrotic and regenerating fibres, perivascular and
endomysial
infiltrates. Immunofluorescence showed deposits of IgG and
fibrinogen in
the wall of muscle vessels. Complement membrane attack complex
(MAC) deposits
were evident in many blood vessels and on sarcolemma of some
muscle fibres.
The predominant cell subsets within the infiltrates were CD4+
and CD68+.
Reverse transcription in situ polymerase chain reaction showed
positive
signals in several endomysial cells surrounding muscle fibres.
Double staining
immunocytochemistry with CD markers and monoclonal ab against
HCV core
NS3 antigen documented positivity in some CD8+ cells.
Our findings confirm the known
resistance
of muscle fibre to viral infection and indicate that HCV is
confined to
infiltrating cells like in myositis associated with HIV and
HTLV-I. The
perifascicular atrophy, the deposits of IgG and MAC in the wall
of the
intramuscular vessel resemble the features usually encountered
in dermatomyositis
and suggest an antibody-dependent pathogenesis, mainly directed
against
the capillary endothelium, in HCV myositis.
RECURRENT MYOGLOBINURIA AFTER TRICHLOROETHYLENE INHALING
Carlo Doriguzzi*, Aldo Cottino°, Tiziana Mongini, Simona Bortolotto, Ivana Bosone, Loredana Chiadò-Piat, Isabella Ugo, Cristina Borghese, Laura Palmucci
*Ospedale E Agnelli, Pinerolo, °Ospedale Valdese di Torre Pellice, Centro per le Malattie Neuromuscolari P Peirolo, Università di Torino
Tricloroethylene (TCE) is a
halogenated
hydrocarbon, like chloroform, widely used as dry-cleaning agent
and industrial
solvent. Depression of central nervous system, deep narcosis,
coma, cardiac
arrhythmias are the effects of TCE inhalation reported in
occasional, acute
poisonings; axonal neuropathies are possible consequences of
chronic professional
exposure.
A 37-year old man with a
history
of alcoholism, was studied for two episodes of rhabdomyolysis
occurring
after TCE abuse through vapours inhalation. In the first
episode, CK serum
levels raised up to 32000 U/l, in the second to 1000 U/l.
Neurological
examinations, renal and hepatic functions were normal. Muscle
biopsy, performed
after CK normalization, showed moderate fibre size variability
and slight
hyperactivity of oxidative enzymes. Biochemical analysis
excluded the enzyme
defects commonly related to rhabdomyolysis.
The effects of TCE on muscle
are
poorly known. Some experimental findings have shown an effect on
muscle
membranes, inducing a higher Ca++ release and enhancing
contraction; its
clinical significance is however still unclear. In our case the
concurrent
alcohol addiction could be relevant, causing a subclinical
myopathy and
enhancing the effects of TCT on muscle.
Absence of apoptosis in
skeletal
muscle tissue of PEO patients with mutations in the Adenine
Nucleotide
Translocator 1 gene
G. Fagiolari, M. Sciacco, C.
Lamperti,
A. Prelle, L. Chiveri, G.P. Comi, A. Bordoni, M.P. Perini, G.
Scarlato,
M. Moggio
Centro Dino Ferrari,
Dipartimento
di Scienze Neurologiche, University of Milan, Ospedale
Maggiore-Policlinico
IRCCS, Via F. Sforza 35, Milan, Italy; Tel: 02-55033851, e-mail:
maurizio.moggio@unimi.it
Autosomal dominant progressive
external
ophthalmoplegia (adPEO) is a human disease associated with
multiple mtDNA
deletions. Linkage analysis assigned some affected families to
the 4q34-35
locus. Recently, mutations have been identified in the nuclear
gene encoding
the heart/skeletal muscle isoform of the adenine nucleotide
translocator
1 (ANT-1), located in the critical region of the 4q locus.
Because ANT-1
is also a structural component of the mitochondrial permeability
transition
pores, and has a role in mitochondrial-mediated apoptosis, it is
hypothesized
that apoptosis may have a role in the pathogenesis of adPEO
caused by ANT-1
mutations.
To verify this hypothesis, we
studied
muscle biopsies from seven patients from five 4q-linked adPEO
families.
We used TUNEL reaction as a marker of nuclear DNA fragmentation,
and antibodies
against pro- (Fas, Bax) or anti- (Bcl-2) apoptotic factors.
Also, we performed
ultrastructural studies.
In all cases, we found no
significant
expression of both pro- and anti-apoptosis related proteins, nor
did we
find TUNEL positivity. This finding is confirmed by lack of
morphological
evidence of apoptosis in all the fibers examined at
ultrastructural level.
We conclude that ANT-1 defects cause accumulation of multiple
mtDNA deletions
and the consequent adPEO phenotype by a mechanism other than the
apoptotic
one.
Further delineation of
diagnostic
criteria of Congenital Muscular Dystrophy based on 16 patients
Raffaele Falsaperla, Angelo Di
Giorgio,
Giusi Romeo, Gianluca Trobia #, Tatiana Trigilia e Piero Pavone
Department of Pediatrics,
University
of Catania, Italy, and # Department of Pediatrics, Azienda
Ospedaliera
“Cannizzaro”, Catania, Italy
The CMD are an heterogeneous
group
of diseases characterized by a marked weakness, generalized
hypotonia,
joint contractures and a muscle histology suggestive of
dystrophic changes.
They are divided into pure or classical form and another group
including
Fukuyama muscular dystrophy, Muscle Eye Brain and Walker-Warburg
syndrome
(WWS) which are associated with cerebral abnormalities.
Following discovery
of merosin, a muscular protein, pure CMD was subdivided into
merosin positive
(normal distribution) and in merosin negative (no
immunostaining) types.
We have reviewed the clinical,
neurophysiologic,
neuroimaging data of 16 patients that were divided in two
groups, the first
one (Group A) included 14 cases with merosin positive CMD and
the second
(Group B) 2 patients with WWS.
Regarding the group A 6 out of
14
had a clinical onset in the neonatal time with arhtrogryposis,
the others
had the clinical onset after 6 months of age. The muscle biopsy
showed
the typical dystrophic pattern in 10 and 3 had the myopathic
picture and
in only one there was not evidence muscular damage. In the group
B the
clinical onset was during the first day of life with muscle
biopsy typical
of muscular dystrophy.
These preliminar data show the
necessity
of a new definition and classification.
Neuropsychiatric evaluation in
Becker
muscular dystrophy patients
Raffaele Falsaperla, Angelo Di
Giorgio,
Giusi Romeo, Tatiana Trigilia, Anna Sorge e Piero Pavone
Department of Pediatrics,
University
of Catania, Italy
Becker muscular dystrophy (BMD)
is an allelic disease due to a partial deficiency of a
cytoskeletal muscular
protein called dystrophin (dys). The dys gene is localised on
short arm
of X chromosome. BMD is a progressive disorder characterised by
progressive
degeneration of muscular skeletal tissue without central nervous
system
(CNS) involvement. The typical BMD represents the benign variant
of Duchenne
Muscular Dystrophy (DMD) and the symptom of onset is usually
proximal weakness.
After the dys discovery there are, also, atypical BMD with
slight muscular
symptoms as cramps, myalgias, fatigability, dilatative
cardiomyopathy and
in rare cases psychiatric disturbances.
The literature shows evidence
of
neuropsychiatric onset in BMD patients without muscular
symptoms. In the
Unit of Pediatric Neurology we have evaluated 20 BMD patients
(ranged from
4 to 25 years) diagnosed by muscle biopsy and confirmed by gene
deletion.
We have examined the degree of
muscular
involvement by Vignos Scale and performed neuropsychological
tests to correlate
the BMD to the psychiatric disorders.
We have noted that in 1/20
patient
was made a diagnosis of schizophrenia and in 6/20 were evidences
of attention/hyperactivity
disorders (ADHD). In conclusion we have to consider that BMD
patients could
have neuropsychiatric disturbances also as unique clinical sign
of the
disease.
ATYPICAL
CLINICAL PRESENTATION
OF PYRUVATE DEHYDROGENASE DEFICIENCY
I. Fiocchi1, L. Doria Lamba1, A. Tessa4, A. Pessagno1, M. Bado2, M.C. Schiaffino3, U. Caruso3, A. Frau1, C. Bruno2, E. Bertini4, F.M. Santorelli4
1Dept. of Neurological and Visual Sciences, 2Neuromuscular Diseases Unit, 3Clinical Pediatric Unit, University of Genova, Istituto «Giannina Gaslini», Genova; 4Div. of Molecular Medicine, Bambino Gesù Children’s Hospital, Rome, Italy
We report on a 2-year-old boy,
first
child of unrelated healthy parents, who presented at birth with
generalized
hypotonia. At three months of age he started to present episodes
of weakness,
with bilateral ptosis, ophthalmoplegia and respiratory distress,
triggered
by fever. Laboratory investigations revealed increase levels of
lactate
and pyruvate in serum and liquor, and massive urinary excretion
of lactate.
Determination of blood lactate/pyruvate ratio and 3-OH-B/AA
moles ratio
showed altered values. Between these episodes, neurological
examination
showed generalized muscle weakness, areflexia, delay of motor
milestones,
normal intellectual development, and laboratory investigations
revealed
mild increase of lactate and pyruvate in blood and liquor. EMG
showed a
neurogenic pattern on the tibialis anterioris muscle and
myogenic and neurogenic
features on the deltoids. Histochemical analysis of muscle
biopsy did not
revealed any specific alteration. Brain MRI images showed
bilaterally hyperintensity
in the globus pallidus. Genetic analysis of the E1? gene of the
pyruvate
dehydrogenase complex revealed a previously reported mutation in
exon 8,
R236G. Substitutive treatment with thiamine was instituted.
The benign clinical evolution
together
with the mild alterations in CNS collocates our cases in an
intermediate
form between the severe and lethal neonatal form and the
moderate one.
Histological, Histochemical
and biochemical
analysis in KEARNS-SAYRE Syndrome: a case report
M. Fratta, M.A.B. Melone, C.
Coppola,
F. Santorelli, A. Gallo, and R. Cotrufo
Division of Neurology,
Department
of Neurological Sciences, - Second University of Naples
Indirizzo autore di
riferimento:
Mario Fratta Clinica Neurologica Policlinico Ed.10 Via Sergio
Pansini,
5 - 80131 Napoli, e-mail:mario.fratta@unina2.it
Mitochondrial syndromes
represent
a heterogeneous group of pathologies which frequently involve
Central Nervous
System and/or Peripheral Nervous System and skeletal muscles.
Mutations
are found more frequently in mitochondrial DNA (mtDNA) than in
nuclear
DNA (deletions, duplications, point mutations, etc.).
The Kearns-Sayre Syndrome (KSS)
is a progressive multisystem disorder characterized by
progressive external
ophthalmoplegia associated to multiorgan involvement (mainly
heart conduction
block, retinal degeneration, neurosensorial deafness, mental
retardation,
myopathy, etc.). Herein we report the case of a 42 years-old
man, who presented
a bilateral II-degree ptosis, external ophthalmoplegia, ataxic
gait, neurosensorial
deafness, diffuse weakness, mental retardation and left
conduction block.
The symptoms onset was in the second decade of life and
progressed very
slowly. Serum biochemical findings showed high levels of CK
(2020 U/l)
and lactic acidosis (3.8 mmol/l at rest; 4.4 mmol/l after 10
minutes of
ischemia). His mother suffered from a bilateral neurosensorial
deafness
and cardiac conduction block. EMG test revealed a myopathic
pattern; muscle
biopsy demonstrated: marked variation in the size of fibers with
large
and small fibers being intermingled in a random pattern;
deposition of
fat within the muscle fibers at lipid staining; more than 30% of
fibers
lacking glycogen and cytochrome-oxidase; typical ragged-red
fibers at the
Gomori staining. Genetic analysis evidenced a large deletion in
the mtDNA.
Primary cell coltures were obtained by muscle and skin
specimens; mtDNA
analysis revealed the following mutation percentage: 36% in
myoblasts;
34 % in skin fibroblasts; 28 % in muscle fibroblasts, while it
was found
86% in skeletal muscle fibers. Considering that patients with
KSS may differ
widely in the severity of symptoms and disability, we
hypothesize that
DNA analysis extended to the isolated cell coltures, may
represent a key
role in the understanding the correlation genotype-fenotype.
The postural draining: long
term
treatment of the respiratory failure in Duchenne patients
M.A.M. Giugliano, R. Russo, L.
Isoldi,
R. Marotta, A. Schiavone, G. Graziani and G. Nigro
Servizio di Cardiomiologia e
Genetica
Medica II
Università - Napoli
Many neuromuscular diseases and
especially the primitive myopathies and, more particularly, the
Duchenne
Muscular Dystrophy, because of the weakness of the thoracic
muscles, determine
the loss of an efficacious cough. This phenomenon causes a
secretion’s
stagnation, due to the progressive destruction of the
“ciliary
escalator”, for the happen of many infectious
episodes.
Though the mechanical
ventilation
can be a very important method for the treatment of the
respiratory failure
in Duchenne patients, procrastinating the respiratory
insufficiency, the
daily postural draining can be useful, especially in some
subjects with
abundant bronchial secretions; the stagnation of these
secretions determine
the happen of phlogosis episodes of the respiratory tract.
120 subjects affected by
Duchenne
muscular dystrophy, were submitted to daily postural draining;
all the
patients showed a ventilatory failure; 50% of patients had V.C.
values
= 50% of predicted; 30% of patients had V.C. values = 30% of
predicted
and 20% of patients had V.C. values < 30% of predicted.
The pulmonary scintigraphy: a
further
evaluation parameter of the respiratory failure in Duchenne
patients
M.A.M. Giugliano, L. Politano,
R.
Russo, A. Bordo, A. Rossi, A. Faraone, G. Gallos, G.L. Cascino,
P.F. Rambaldi
L. Mansi
Servizio di Cardiomiologia e
Genetica
Medica, Servizio di Medicina Nucleare - II Università - Napoli
The ventilatory and perfusive
pulmonary
scintigraphy, not invading medico-nuclear technique, influenced
the diagnosis
of some diseases and, in particular, of the pulmonary embolism.
This method
can be used to diagnose many diseases, as well as inflammatory
or infiltrative.
The neuromuscular diseases are frequently characterized by a
severe and
increasing ventilatory deficit; the Duchenne muscular dystrophy
is the
disease that, more typically, shows a precocious and increasing
respiratory
failure. For an evaluation by images of the pulmonary function,
20 subjects
affected by DMD, in various phases of the disease and with a
restrictive
disventilatory syndrome, were submitted to pulmonary perfusive
and ventilatory
scintigraphy.
Apoptosis and emerin
processing
in muscle cells
Giovanna Lattanzi1, Elisabetta
Mattioli2,
Marta Columbaro2, Cristina Rutigliano3, Andrea Ognibene3,
Cristina Capanni3,
Nadir Mario Maraldi1,3, and Stefano Squarzoni1.
1Institute of Normal and
Pathological
Cytomorphology, CNR, c/o IOR; 2Laboratory of Neuromuscular
Pathology, Istituti
Ortopedici Rizzoli; 3 Laboratory of Cell Biology and Electron
Microscopy,
Istituti Ortopedici Rizzoli, Bologna, Italy.
Involvement of apoptosis in
muscle
disease has been suggested by several authors. However, the role
that proteins
mutated in muscular dystrophies play in the apoptotic process is
still
unclear. Emerin is an integral nuclear membrane protein which is
lacking
or mutated in the Emery-Dreifuss muscular dystrophy. We induced
apoptosis
in cultured myoblasts to evaluate emerin fate during programmed
cell death.
Emerin processing was evaluated by Western blot analysis and
compared to
proteolysis of lamin A/C. Emerin proteolysis occurred in
apoptotic myoblast
nuclei and emerin staining at the nuclear rim decreased in these
cells.
Myoblast apoptosis and emerin degradation were associated with
morphological
changes including chromatin compaction and detachment from the
nuclear
lamina, as detected by electron microscopy. In vivo inhibition
of caspase
6 activity affected emerin proteolysis in apoptotic cells: this
finding
suggests that emerin cleavage depends on this enzyme. Our
results show
that the process of programmed cell death leads to emerin
proteolysis in
myoblasts: this process appears to be related to caspase 6
activation and/or
to cleavage of other nuclear lamina proteins, such as LAP2, LBR
and lamin
A/C that share sequence homologies or functional features with
emerin.
RESPONSE TO ERGOMETER STRESS TEST IN ATHLETES WITH HYPERCKEMIA
F.M. Limongelli, P. Brancaccio, A. Palladino, A. Della Pietra, L. Passamano, L. Fioretti, and L. Politano
Dipartimento di Internistica Clinica e Sperimentale “ F. Magrassi “ - Cattedre di Medicina dello Sport e di Genetica Medica - Seconda Università di Napoli
The increase in CK values obtained after training is caused by a damage of sarcolemma and is closely related to length, intensity and type of exercise. The pattern of muscular isoforms (CK and LDH) in a group of athletes (15; group A) with increased values of CK was evaluated and compared with a control group (20; group B) with normal CK values. All the subjects, age, sex and sport-matched, underwent ergometer stress test with the evaluation of serum values of CK, LDH and related isoforms at resting, at 5 minutes by the effort end, and at 6, 24 and 48 hours. CK values at rest were significantly different in the two groups (185.9 U/L in group A versus 49.3 U/l in group B; p = 0.03) and did not vary throughout the entire period of observation. Interestingly, 48 hours after the stress test, 71.4 % of the athletes in group A showed CK values still elevated, compared with 0% of the athletes in group B. The data were statistically evaluated (Student T test for non paired data, chi square test). We hypothesize that the lack of recovery in the athletes of group A is related to an underlying damage of the muscular membrane and deserves further investigation from a genetic point of view.
Phenotypic heterogeneity in
myotonic
dystrophy with no CTG repeat expansion
R. Massa, G. Koch, A.
Martorana,
V. D’Angelo, G. Sancesario, G. Novelli* and G.
Bernardi
Clinica Neurologica, and
Cattedra
di Genetica Medica*, Università di Roma-Tor Vergata
In recent years, a disorder
similar
to myotonic dystrophy (DM) but lacking the CTG repeat expansion
at the
DM1 locus has been described. Most of these patients show a
peculiar phenotype,
defined as proximal myotonic myopathy (PROMM) and characterized
by predominant
proximal muscle weakness, myalgia, facial muscle sparing and by
mild histological
changes. However, to date there are no clues as to the
pathogenesis of
this entity, and ultrastructural studies of muscle are lacking.
We report
the clinical, histopathological and ultrastructural findings of
patients
from two families presenting with a multisystem disease
including myotonia,
myalgia, facial and distal muscle weakness and atrophy,
cataracts and white
matter abnormalities on brain MRI. However, CTG repeat
expansions at the
DM1 locus were not found in either of the probands. In family1,
other clinical
features were: proximal muscle weakness, mental retardation and
possible
clinical anticipation. A linkage analysis of this family ruled
out the
involvement of the DM1 locus. Muscle biopsy in the probands
showed severe
alterations in family 1, with large group atrophy and scattered
necrosis
and moderate changes in family 2. In both cases, ring fibers and
sarcoplasmic
masses, typical of DM, were absent. These findings demonstrate
that DM
without trinucleotide repeat expansion can present clinical and
histopathological
features intermediate between DM1 and PROMM.
SELECTIVE ANTIBODY
NEUTRALIZATION
OF IGF-I AND IGF-II CORRELATES WITH DIFFERENT
MITOGEN-ACTIVATED PROTEIN
KINASE SIGNALING PATHWAYS IN DMD MYOBLASTS
M.A.B. Melone, U. Galderisi*,
G. Peluso** and R. Cotrufo
Division of Neurology,
Department
of Neurological Sciences, *Institute of Pharmacology and
Toxicology, C.R.I.S.C.E.B,
- Second University of Naples and ** C.N.R, Naples
Indirizzo autore di
riferimento:
Marina Melone Clinica Neurologica Policlinico Ed.10 Via Sergio
Pansini,
5 - 80131 Napoli, e-mail: marina.melone@unina2.it
The extracellular signal-regulated kinase (ERK) and the c-jun kinase (JNK) are two MAP kinases that could play a role in the DMD myoblast response to IGFs growth factors. Antibody neutralization of IGF-I contained in DMD muscle extract culture media, as well as antibody neutralization of IGF-I receptor, significantly increased ERK phosphorylation of DMD myoblasts and the activity of its downstream substrate, the p90 ribosomal S6 kinase 2 (RSK2), by 1.5-folds, but it had no effects on JNK activity. In contrast, antibody neutralization of IGF-II had no effect on ERK phosphorylation or RSK2 activity, but it increased JNK activity by twofold, an effect that was inhibited by specific antibodies against JNK. Furthermore, the phosphorylation of both p46 and p55 isoforms of JNK, measured by phosphospecific antibody, was increased several folds. The activity and phosphorylation of MAP kinase kinase (MKK)-4, an upstream regulator of JNK, was unchanged when IGF-II was inhibited. IGF-I and IGF-II have different effects on MAP kinase signaling pathways in DMD myoblasts, which may be one of the underlying mechanisms through which IGFs could control the DMD myoblast growth.
Rigid Spine congenital
Muscular Dystrophy
(RSMD1): clinical and muscle imaging data in 5 patients
Luciano Merlini1, Beril Talim1,
Behzad Moghadaszadeh2, Nathalie Petit2, Pascale Guicheney2
1 Neuromuscular Unit, Istituto
Ortopedico
Rizzoli, Bologna, Italy, and 2 INSERM U 523, Institut de
Myologie, Groupe
Hospitalier Pitie-Salpetriere, Paris, France
Rigid Spine congenital Muscular
Dystrophy (RSMD1) is an autosomal recessive condition
characterised by
mild weakness of the girdle and limb muscles, early and diffuse
contractures,
severe progressive shortening and weakness of the trunk muscles
leading
to fixation and loss of movement of the spine and the thoracic
cage, resulting
in rigid spine, scoliosis, and early restrictive respiratory
failure. The
gene has been mapped on chromosome 1p35-36. We have studied 5
patients
in 3 families affected by RSMD1. Onset of symptoms was at birth
in one,
in the first year of life in 3, and at the age of 4 in one.
First steps
were before the age of 18 months. Facial and neck weakness were
present
in all. Mouth opening was particularly limited in 3. All had
nasal voice.
They were thin with diffuse muscle wasting. Muscle weakness was
usually
4/5 in the shoulder girdle and proximal limb muscles. Finger
extensors
were particularly weak (2-3/5). Hip girdle muscles were 2-3/5.
The contractures
were more prominent in the proximal joints and in the spine.
Scoliosis
had an early onset (5 to 10 years of age) and at least in 2
cases a rapid
characteristic progression with rigid lordoscoliosis, lateral
bending and
flexion of the trunk. Cardiac evaluation was normal. Vital
capacity was
severely reduced. The 4 older were mechanically ventilated with
Bipap at
night. CPK was mildly elevated in two (1.5-3 times normal).
Muscle CT showed
a peculiar consistent pattern. Selective involvement of the
paravertebral,
sartorius, adductors, biceps femoris and gastrocnemius muscles
at an early
stage; more diffuse involvement in older patients; long-lasting
sparing
of the rectus femoris and gracilis muscles.
ROLE OF
CAVEOLINS IN MUSCULAR
DYSTROPHIES
U.O. Malattie Neuro-Muscolari, Dipartimento di Pediatria dell’Università di Genova, Istituto G. Gaslini, Largo Gaslini 5, 16147 Genova. Tel 010-5636603; Fax 010-3532364; E-mail: minettic@unige.it.
Mutations in the caveolin-3
gene
(CAV3) cause a severe deficiency of caveolin-3 protein
expression in muscle
fibers and are associated with a specific form of autosomal
dominant limb
girdle muscular dystrophy (LGMD1C) (Minetti et al, 1998). We
recently described
a novel mutation in CAV3 gene in two unrelated children with
partial caveolin-3
deficiency and isolated hyperCKemia, without any clinical
symptom of myopathy.
This is the first demonstration of a new phenotype associated to
CAV3 mutations
and indicates that a partial caveolin-3 deficiency should be
considered
in the differential diagnosis of idiopathic hyperCKemia.
In DMD muscle, we found an
increased
number of caveolae at the sarcolemma that corresponds to an
over-expression
of caveolin-3. These data suggest a possible role for caveolae
and caveolin-3
in the pathogenesis of DMD. To test this hypothesis, wild-type
caveolin-3
was overexpressed as a transgene in mice. Transgenic mice
over-expressing
caveolin-3 show a dystrophic pattern and virtually undetectable
levels
of dystrophin. To understand a possible mechanism to explain
this phenotype
we demonstrated that caveolin-3 directly interacts with
beta-dystroglycan
and that this interaction may competitively regulate the
recruitment of
dystrophin to the sarcolemma. Taken together, this findings may
open new
perspectives in elucidating the pathogenesis of muscular
dystrophy.
EPIDEMIOLOGY
OF DUCHENNE
MUSCULAR DYSTROPHY IN THE PROVINCE OF TURIN: RESULTS AFTER
TWENTY YEARS
OF COUNSELLING
Tiziana Mongini, Carlo Arduino§, Patrizia Boffi*, Laura Jarre°, Franco Fiocchi§, Carlo Doriguzzi^, Laura Palmucci
Dipartimento di Neuroscienze, Centro per le Malattie Neuromuscolari P Peirolo, *Dipartimento di Neuropsichiatria Infantile, OIRM, Università di Torino; ° Sezione di NPI, Ospedale Martini, Torino; § Dipartimento di Genetica Medica, Università di Torino
In 1980 our epidemiological
survey
of DMD in the province of Turin found an incidence of 24.23
x10-5, meaning
1 case in 4127 live male births during the years 1955-1974. The
prevalence
rate was 2.15 x 10-5. These results were comparable with other
data in
the world literature at that time.
After the identification of
dystrophin,
a new approach to genetic counselling for the disease allowed
accurate
carrier identification and prenatal diagnosis, with reduction of
new cases
in informative families. On the other hand, the great advances
of mechanical
ventilation in the last decade allowed a prolonged survival of
DMD boys,
now reaching the fourth decade.
To verify the efficacy of
counselling
in our Province, we performed a second survey, considering the
years 1992
-1999. A total of 35 prenatal diagnoses for DMD were performed,
resulting
in 18 female, 15 normal male, and 2 DMD affected male fetuses.
No new familial
case was observed. According to preliminary data, six DMD boys
were born
in this period, corresponding to an incidence rate of 7.5 x10-5.
On the
contrary, prevalence did not significantly differ from 1974,
also due to
new cases among immigrated population. The median age of DMD
patients was
increased.
Nuclear factor kappa B
expression
in inflammatory myopathies
M.C. Monici, A. Mazzeo, M.
Aguennouz,
G. Vita
Department of Neurosciences,
Psychiatry
and Anaesthesiology, Policlinico Universitario, Messina
Nuclear factor-kB (NF-kB) is an
ubiquitous rapid response transcription factor in cells involved
in immune
and inflammatory reactions, and exerts its effect by expressing
cytokines,
chemokines, cell adhesion molecules, growth factors, and
immunoreceptors.
NF-kB contributes to immunologically mediated diseases such as
allograft
rejection, rheumatoid arthritis, and bronchial asthma. It is
also thought
to play an important role in the expression of genes expressed
in response
to ischemia/reperfusion injury. We studied expression of NF-kB
by immunocytochemistry
and western blot in skeletal muscle specimens from 5 patients
with polymyositis
and 5 patients with dermatomyositis. Immunohistochemistry for
macrophages,
B, CD4 and CD8 cell subsets, and major histocompatibility
complex class
I and II antigens was also investigated. NF-kB expression was
found in
some vessel walls, in several atrophic myofibers especially
those with
a perifascicular distribution, and in a few infiltrating cells.
Results
suggest that NF-kB plays little pathogenic role in the advanced
phases
of inflammatory myopathies.
1Department of Neurological Sciences, Psychiatry and Anaesthesiology, University of Messina, Italy, and 2Department of Neurology, Columbia University, New York, New York.
A mitochondrial
encephalomyopathy
with Coenzyme Q10 deficiency has been reported in the last few
years in
an increasing number of patients. A central nervous system
involvement
with epilepsy, or ataxic syndrome often occurred.
In a series of 35 muscle
biopsies
from patients with cerebellar syndrome in whom cerebellar ataxia
could
not be attributed to specific metabolic or genetic causes, we
measured
mitochondrial enzymes activities and Coenzyme Q10 levels.
Decreased CoQ10 levels in
muscle
were found in six patients, with residual amounts varying form
26% to 35
% of controls. Muscle biopsies showed minimal morphological
changes with
no specific mitochondrial markers. Biochemical assays of
mitochondrial
respiratory chain enzymes evidenced in 2 patients reduced
activity of complex
III. MRI of the brain showed severe cerebellar atrophy. All six
patients
were treated with oral CoQ10 therapy ( 600-1200 mg/die) for one
year. The
patients were evaluated before and after one year of replacement
therapy.
Clinical improvement was assessed with the
“International Cooperative
ataxia rating scale”.
Our results suggest that a
Coenzyme
Q10 deficiency should be considered in patients with
unclassified cerebellar
ataxia especially considering the benefits of a specific
metabolic treatment.
ASSOCIATION OF MITOCHONDRIAL ENCEPHALOMYOPATHY
WITH CoELIAC DISEASE: IMPROVEMENT OF CLINICAL AND
NEURORADIOLOGIC FEATURES
AFTER INTRODUCTION OF GLUTEN-FREE DIET
F. Odoardi, M. Rana, A. Modoni, A. Broccolini, A. Spinazzola, P. Tonali, S. Servidei and G. Silvestri
Neurological Institute, Catholic University, Rome, Italy
Malabsorption due to a
metabolic
mitochondrial dysfunction is a cardinal feature in MNGIE and in
other infantile
mitochondrial disorders with villous atrophy. We report a
sporadic mitochondrial
disorder in whom malabsorption was instead due to the
concurrence of a
celiac disease. A 19 year-old boy had developed diabetes at age
7. Three
years later he received a diagnosis of celiac disease confirmed
by intestinal
biopsy. At age 19 he started to complain of gait disturbances,
tremor and
headache. Neurological examination showed ptosis,
ophthalmoparesis, truncal
ataxia, dysarthria, intentional tremor and pyramidal signs.
Brain MRI showed
a diffuse leukoencephalopathy and muscle biopsy showed a
mitochondrial
myopathy associated with dimers of a 8kb deletion of mtDNA. An
extensive
metabolic screening and CSF examination gave normal results,
while vitamin
E and folate were below normal. Based on these findings, we
prescribed
a strict gluten-free diet. Dietetic treatment produced a marked
amelioration
of ataxia and tremor and also brain MRI showed a mild but
significative
improvement of white matter abnormalities.
This report underlines the
importance
of performing accurate studies for malabsorption associated with
mitochondrial
disorders in order to assess the most accurate treatment and to
prevent
any progression of the disease due to misdiagnosis.
MITOCHONDRIAL
ENCEPHALOMYOPATHY
IN ONE OF TWO MONOZYGOUS TWINS
Dipartimento di Neuroscienze, Centro per le Malattie Neuromuscolari P Peirolo, Università di Torino; *Divisione di Neurologia, Ospedale di Asti; °Clinica Neurologica, UCSC, Roma
Mitochondrial diseases include
a
large variety of clinical expressions often with multisystem
involvement.
The attainment of the central nervous system rarely features an
extrapyramidal
syndrome: parkinsonism was described associated with a 4bp
deletion of
cytochrome b gene and dystonia has been found both associated
with Leber
optic atrophy and with myopathy, in the presence of different
point mutations
of mitochondrial DNA. We observed a 48 years old man with a
healthy identical
twin. He has been complaining of impaired gait for the past two
years.
Neurological examination showed a dystonic attitude appearing on
attempted
walking compelling the patient to walk on his toes, increased
muscle tone
in the lower limbs, distal hypotrophy of the lower limbs and
diffuse proximal
muscle weakness, limitation of the flexo-extension of the feet,
slight
bilateral dysmetria. Serum CK was 449 U/l, EMG showed myopathic
features.
ECG was normal. Brain MRI disclosed atrophy of the vermal
portion of the
cerebellum and hyperintensive areas in the nuclei pallidi.
Muscle biopsy
demonstrated a mitochondrial myopathy with partial cytochrome c
activity.
Mitochondrial DNA analysis is in progress.
The interest of the case lays
on
the unusual clinical expression, involving the extrapyramidal
system, and
in the appearance of the disorder in only one of two identical
twins, suggesting
an extreme degree of heteroplasmy.
Late onset multisystem
disorder
with muscle mitochondrial DNA
depletion:
a case report
M.P. Perini, M. Sciacco, S.
Galbiati,
A. Bordoni, C. Lamperti, G.P. Comi, M. Moggio, E. Scarpini, N.
Bresolin,
G. Scarlato
Centro Dino Ferrari,
Dipartimento
di Scienze Neurologiche, Università degli Studi di Milano, IRCCS
Ospedale Maggiore Policlinico, via F. Sforza 35, 20122 Milano,
Italy. E-mail:
gpcomi@mailserver.unimi.it
Quantitative mitochondrial DNA
(mtDNA)
defects have been associated with mitochondrial disorders,
usually characterised
by infantile or childhood onset of progressive myopathy, and/or
hepathopathy,
encephalopathy and renal involvement. Individuals exhibit
variable levels
of mtDNA depletion (up to 98%) in affected tissues. In addition,
different
tissues may be involved in related patients. The primary
pathogenetic mechanism
underlying mtDNA depletion is unknown.
We now describe a 26 year-old
female
patient born from healthy, non-consanguineous parents, affected
with a
late onset mitochondrial disorder. She attended school till the
age of
13 and developed normally until the age of 14 years, when a
primary hypothalamic
amenorrhoea was found. At age 24 she began to complain fatigue
after a
mild muscular exercise with proximal muscle weakness. Serum CK
and rest
lactate levels were elevated (CK: 1691 U/l ; n.v.: <200;
lactate 28,8
mg% ; v.n.: <19,8 mg%). Neuropsychological investigations
revealed a
mild mental impairment (MMSE: 26/30; WAIS: 71; n.v.: >69).
Brain CT and
MRI showed two lesional areas in the left fronto-mesial and
right thalamic
associated with hyperintense bilateral signal alterations in the
hemispheric
white matter. CSF and EEG were normal. Fundus oculi revealed a
dystrophic
maculopathy. EMG demonstrated chronic mild myopathy in proximal
muscles
without active denervation and associated mild neuropathy.
Muscle biopsy
revealed marked fiber size variability, many central nuclei,
some necrotic
fibers with a macrophagic infiltration. A high percentage of
fibers showed
strong SDH activity and COX deficiency. Immunohistochemistry
revealed the
presence of CD4, CD8 positive cells and a milder CD19
positivity. Quantitative
Southern blot analysis revealed the presence of 20 % residual
muscle mtDNA.
This patient, sixth report of a late-onset of mtDNA depletion,
is peculiar
for the age, the dramatic dystrophic-like and inflammatory
aspects of the
muscle biopsy, and the nature of central nervous system
involvement.
A. Pini, M. Giannotta, G. Melideo, G. Gobbi, § A. Berardinelli, § M. Rossi, § C. Conti, § G. Lanzi, # L. Jarre, # P. Dassi, * E. Della Giustina, ^ M. Santucci, ** M. Mora, ** L. Morandi
Child Neuropsychiatry Unit, Maggiore Hospital, Bologna; §Child Neuropsychiatry Unit, IRCCS Mondino, Pavia; #Child Neuropsychiatry Unit, Martini Hospital, Turin; *Child Neuropsychiatry Unit, S.Maria Nuova Hospital, Reggio Emilia; ^ Child Neuropsychiatry Unit, Bologna University; ** Neuromuscular Unit, C.Besta Neurological Institute, Milan; ITALY.
Diagnostic role of muscle biopsy and DNA analysis in a cohort of pediatric patients investigated for incidental hyperCKemia. Clinical and laboratoristic findings including muscle biopsy of 75 patients, aged 11 months-12 years at the time of biopsy ( follow-up 6 months-11 years ), presented with an incidental, asymptomatic, persistent serum creatine kinase ( CK ) increase were reviewed. Muscle biopsies were studied by light microscope and, when indicated, biochemical and/or ultrastructural examinations were performed. In cases with normal or myopathic-dystrophic histological picture the immunohistochemical evaluation of dystrophin was made. Patients with dystrophinopathy were investigated by DNA analysis for dystrophin gene deletions and/or by further immunohistochemical tests. In 37 patients out of 75 a preclinical diagnosis of a specific muscle disorder was obtained. In 38 cases the cause of hyperCKemia remained unknown. Pediatric patients presented with incidental asymptomatic hyperCKemia must be studied with muscle biopsy and appropriate DNA analysis which may discover a preclinical myopathy in a high percentage of cases. The chapter of Idiopathic iperCKemia must be revisited by the light of new etiopathogenetic knowledges and techniques. A diagnostic protocol is proposed. The approach to the diagnosis by the investigation of many muscle-membrane proteins as first step is discussed.
Politano, V. Nigro*, V. Petretta, L. Passamano, G. Piluso*, A. Belsito*, M.G. Esposito, V. Ventriglia*, S. Aurino*, A. Palladino, L.I. Comi, G. Nigro
Dipartimento di Internistica Clinica e Sperimentale “F. Magrassi” - Sezione di Cardiomiologia e Genetica Medica; * Istituto di Patologia Generale - Seconda Università di Napoli
Clinical, genetic and
epidemiological
aspects have been evaluated in 140 patients, followed at the
Cardiomiology
and Medical Genetics of 2nd Naples University, affected by
limb-girdle
muscular dystrophies and in 328 relatives, seeking genetic
advice, in order
to study the occurrence of the autosomal recessive muscular
dystrophies
in Southern Italy, to correlate the clinical features with the
wide spectrum
of genetic variability, to detect the gene carriers, to allow a
prenatal
diagnosis. All the patients underwent clinical examination,
standard and
dynamic ecg, ecocolordopplercardiography, spirometric
evaluation, DNA analysis
and/or muscle biopsy. So far, 24 patients with
sarcoglycanopathy, 47 with
calpainopathies, and 3 with mutations in the telethonin gene
have been
identified. The clinical features of patients were related to
the type
of mutation. A prenatal diagnosis was made in 2 families,
respectively
with gamma and delta sarcoglycanopathy and resulted in 3 not
affected fetuses.
Calpainopathies seem to be the most diffuse form of limb-girdle
muscular
dystrophy, reaching the 25% of all cases. In respect of
sarcoglycanopathies,
calpainopathies show a less severe clinical course, a grater
incidence
of heart conduction defects and of respiratory involvement.
A careful estimate of carriers
in
the general population will consent a more effective genetic
counselling
and an accurate prenatal diagnosis.
DETECTION OF CARRIERS OF
DUCHENNE/BECKER MUSCULAR DYSTROPHIESL.
Politano, V. Nigro * , G. Passamano,
M.G. Esposito, L.I. Comi and G. Nigro
Dipartimento di Internistica Clinica e Sperimentale Sezione di Cardiomiologia e Genetica Medica - e * Istituto di Patologia Generale - II Università di Napoli - Naples - Italy
During the last 7 years 1153
females
sought advice to the genetic counselling of Cardiomyology and
Medical Genetics
of 2nd Naples University. This large group included females
closely related
to Duchenne/Becker patients, often dead before the DNA analysis
era, and
females with increased serum CK values and a negative family
history for
dystrophinopathy. The first step of this process was to identify
the causative
mutation in each family and then to test females at risk to
detect mutations.
In families with dystrophin gene deletions or duplications, the
carrier
status was ascertained by quantitative multiple PCR
amplification, using
72 exons. In females without deletion and/or duplication we used
a novel
fully automated instrument (DHPLC, Transgenomic Wave System)
specifically
designed to rapidly separate single-and double-stranded DNA
fragments and
identify the presence of point mutations. Mutations of
dystrophin gene
were identified in 275 (73%) families, 214 Duchenne and 65
Becker. A carrier
status was ascertained in 39.7% of consultants, and was excluded
in 60%.
Forty-three percent of mothers did not show the mutation
detected in their
children; 5 cases of germ-line mosaicism were documented.
Mutations in the dystrophin
gene
were detected in 40 families in which the affected male was not
available
and in 12 females with isolated hyperCKemia.
INCLUSION
BODY MYOPATHY: AN ITALIAN
FAMILY WITH AUTOSOMAL DOMINANT INHERITANCEC.
Dipartimento di Neuroscienze, Scienze Psichiatriche ed Anestesiologiche, Università di Messina, 1 CNR, Cosenza, and 2 Istituto di Scienze Radiologiche Università di Messina
Familial or hereditary inclusion-body myopathy (h-IBM) constitutes a heterogeneous group of debilitating disorders, histologically characterized by presence of “rimmed vacuoles” and filamentous inclusions positive for various alien proteins. Autosomal recessive inheritance (AR-IBM) has been described in quadriceps-sparing h-IBM, linked to chromosome 9p1-q1. Autosomal dominant inheritance has been rarely reported, and no chromosomal linkage has been presented to date. We describe an Italian kindred manifesting clinical features and pathologic changes of D-IBM. In this family six members were affected in four generations with a direct male-to-male and female-to-female transmission. Onset of disturbances ranged from 22 to 28 years of age. In 3 patients the onset of the disease was mainly characterised by a distal weakness at lower limbs; progressive wasting and weakness of proximal muscles were then evident in all affected members. Two also had dysphonia. CK levels were increased (~ 1500 IU/l). To our knowledge this is the first report of D-IBM in our country. Linkage DNA analysis may be helpful to better classify such a disease.
Cognitive and behavioral
assessment
in children with merosine positive non progressive congenital
myopathies
Emanuela Russo, Mariamalia
Battaglia,
Andrea Martinuzzi
IRCCS “E.
Medea”
Conegliano Research Centre
Children with non-progressive
congenital
myopathies are usually very well studied for muscle and cardiac
function,
and figures on extent and frequency of muscle weakness and
cardiopathy
are reported in the literature. Cognitive, linguistic, social
abilities
of these children are much less investigated. Nevertheless,
these variables
are of great importance in determining functional outcome and
quality of
life. We reviewed and assessed cognitive, social, behavioral,
and learning
abilities in 8 children (6 males and 2 females) with biopsy
proven merosin
positive non-progressive congenital myopathy. Present mean age
was 8.8
years (range 2-18). Severity of muscle involvement was moderate
(6) to
severe (2), moderate to severe respiratory problems were
reported in 3.
No cardiomyopathy was reported in the group. The sample was
studied with
formal cognitive (WAIS/WPPSI) and behavioral (CBCL/MOS SF36)
testing, academic
performance was scored according to teacher’s reports.
Mild cognitive
impairment was found in 2 patients, in one of whose linguistic
abilities
and academic performances were compromised. The pathological
diagnosis
in this case was fiber type disproportion. Behavioral-social
problems were
reported in one boy with normal I.Q. Family adaptation to the
children
disabilities was satisfactory in all cases. Children with
merosine-positive
congenital myopathy may show cognitive and behavioral problems
which, albeit
milder than those described in DMD patients, need to be
addressed while
planning a long term rehabilitation project for these subjects.
Multiple Acyl-CoA
Dehydrogenase Deficiency
with Adult Onset
S. Sampaolo, * E. Lamantea,
C.M.
Vincitorio, * M. Rimoldi, M.R. D’Ambrosio, * B.
Garavaglia, G.
Di Iorio
Dipartimento di Scienze
Neurologiche,
Seconda Università degli Studi di Napoli; * Divisione di
Biochimica
e Genetica, Istituto Neurologico “C. Besta”,
Milano
A 49 year-old man was
hospitalised
for recurrent episodes of muscle pain, marked fatigability,
nausea and
vomiting associated with progressive and diffuse muscle weakness
during
the last two years. He complained also of sporadic and mild
attacks of
cramps and fatigue in his legs from age 12. Neurological
examination showed
severe muscle wasting (he lost 15 kg body weight in ten months)
and weakness,
prevailing proximally. CK was 2746 U/l, LDH 3123 U/l, AST 299
U/l and ALT
277 U/l. Electromyography was myopathic. Muscle biopsy showed a
vacuolar
myopathy with lipid storage. Carnitine determination performed
in muscle
showed a severe reduction of free and total fractions with
elevation of
long-chain esters. GC/MS of plasma total fatty acids revealed
the presence
of tetradecenoic acid (C-14:1 w=9). A deficiency of long-chain
fatty acid
oxidation was suspected. Biochemical studies demonstrated a
multiple acylCoA
dehydrogenase deficiency in the muscle. Carnitine (4 g/day),
riboflavin
(100 mg/day) and prednisone (37.5 mg/day) were administered. The
patient’s
clinical condition ameliorated within a month of this therapy.
His muscle
strength improved, his body weight increased from 63 to 66 kg
and CK, LDH,
AST and ALT returned to normal levels. At five months follow-up
the general
condition improve progressively.MEXILETINE IN MYOTONIC DISORDERS:
ASSESSMENT OF
STRENGTH AND MYOTONIA BY QUANTITATIVE MUSCLE ASSESSMENT (QMA)V.
Sansone, K. Marinou, J. Salvucci and G. Meola
Dept. Neurology, Ist. Policlinico San Donato, Univ. Milan
To quantify the effects of
mexiletine
on muscle strength and on grip myotonia in dystrophic and
non-dystrophic
myotonias. Previous trials on a limited number of patients
suggest that
class 1 anti-arrhythmic agents may improve myotonia. A one-month
cross
over trial of 200mg tid of mexiletine vs placebo was performed
in 20 patients
with moderately-severe myotonic dystrophy type 1 (DM1), 10
patients with
proximal myotonic myopathy (PROMM), and 10 patients with
myotonia congenita
(MC). Muscle strength was assessed by quantitative muscle
assessment (QMA)
considering maximum voluntary contraction (MVC) expressed in Kg
as well
as by manual muscle strength testing using the 5-point MRC
scale. Myotonia
was assessed by an arbitrary 4-point of scale of subjective
evaluation
of severity; by timed functional tests and by half relaxation
time after
MVC. All tests were performed at baseline, after the first month
and at
the end of the trial. Mexiletine improves muscle strength in DM1
and especially
in MC. In PROMM patients it rather improves muscle pain. It
reduces half
relaxation time in DM1 but especially in MC.
Mexiletine is a well-tolerated
drug
in the treatment of both muscle weakness and myotonia in the
myotonic disorders,
especially in MC.
Hyperornithinemia,
hyperammonemia
and homocitrullinuria (HHH) syndrome in Italy: a clinical and
molecular
characterization
Filippo M. Santorelli, MD*;
Sergio
Salvi, MSc; Margherita Verardo, BS; and Carlo Dionisi-Vici, MD
Dept. of Neurosciences,
IRCCS-Ospedale
Pediatrico “Bambino Gesù”, Roma, Italy, and
* Molecular Medicine, Bambino Gesù Hospital, Piazza S. Onofrio,
4-00165 Rome, Italy, fax +390668592024; email
fms3@na.flashnet.it
The hereditary spastic
paraplegias
(HSP) are genetically heterogeneous disorders characterized by
degeneration
of the pyramidal tract. It is known that a subgroup of HSP
patients have
features typical of oxidative phosphorylation (OXPHOS) defects
because
of mutations in the SPG7 gene. Hyperornithinemia, hyperammonemia
and homocitrullinuria
(HHH) syndrome is a recessive disease characterized by impaired
ornithine
transport across the inner mitochondrial membrane. Affected
patients usually
present with spastic gait, pyramidal tract signs, and ataxia.
Furthermore,
the abnormal intramitochondrial ornithine transport causes a
functional
impairment of the urea cycle responsible for recurrent
hyperammonemia with
loss of consciousness, lethargy and coma. Mutations in the ORNT1
gene have
been associated with HHH. We investigated eight unrelated HHH
patients
followed by Italian referring centers for inborn metabolic
diseases. In
three patients, we obtained deltoid muscle biopsies to look for
OXPHOS
defects. All patients invariably presented evidence of pyramidal
tract
dysfunction. Worsening of neurological signs did not relate to
relapses
of hyperammonemia that were observed only in patients with a
delayed diagnosis.
Molecular studies demonstrate nine differentORNT1 mutations,
seven of which
are new. Mutations mostly resulted in shorter gene product, via
premature
translation termination. There was no correlation between
residual size
of the predicted ORNT1 gene product and clinical and metabolic
severity.
Interestingly, a R179X nonsense mutation led to exon 4 skipping.
Histochemical
and biochemical studies in muscle showed moderate mitochondrial
proliferation
with abnormally shaped, enlarged mitochondria by electron
microscopy. The
identification of ORNT1 mutations adds a novel mitochondrial
determinant
to the broad group of hereditary spastic paraparesis.
IDENTIFICATION OF TWO NEW MUTATIONS IN THE MYOPHOSPHORYLASE GENE IN ITALIAN
McARDLE’S PATIENTSLucio Santoro1, Claudia Biedi2, Roberta Lanzillo1, Lucia Iadicicco1, Laura Gregori2, Carlo Minetti2, Claudio Bruno2
1Dip. di Scienze Neurologiche, Università di Napoli «Federico II», Napoli, Italy, and 2Lab. di Patologia Muscolare, Università di Genova, Istituto G. Gaslini, Genova, Italy
Genetic defects of
muscle-specific
isozyme of glycogen phosphorylase (myophosphorylase) cause a
metabolic
myopathy (McArdle’s disease) characterized by exercise
intolerance,
myalgia, cramps, and episodic myoglobinuria. Molecular genetic
studies
of the myophosphorylase gene (PYGM) have thus far identified
around 25
different mutations in patients with McArdle’s disease
from different
countries. The most common genetic defect among north-European
and American
patients is a nonsense mutation at codon 49 in exon 1 (R49X),
which seems
to be less frequent in Mediterranean populations.
Here, we report two new
mutations
in the PYGM gene in two unrelated Italian McArdle patients with
documented
histochemical and biochemical phosphorylase deficiency in their
muscle
biopsies. Screening by PCR/RFLP confirmed the presence of the
R49X in both
patients. By sequencing the entire coding region and intron/exon
boundaries
of the PYGM gene of the patients, we identified: i) in patient
1, a novel
heterozygous C-to-T mutation, changing CGA (arginine) to TGA
(stop codon)
at codon 269 in exon 7 (R269X); ii) in patient 2, a novel
heterozygous
G-to-C mutation, changing GCT (alanine) to CCT (proline) at
codon 686 (A686P).
Several lines of evidence suggested the pathogenecity of both
mutations.
Our data further expand the
genetic
heterogeneity in patients with McArdle’s disease.
Familial T8993C mutation
causing
both the NARP and the MILS phenotype in the same generation: a
morphologic,
genetic, and spectroscopic study
M. Sciacco, E.
D’Adda,
G.P. Comi, M. Rango, A. Prelle, C. Lamperti, M.P. Perini, A.
Bordoni, S.
Galbiati, G. Scarlato, M. Moggio
Centro Dino Ferrari,
Dipartimento
di Scienze Neurologiche, University of Milan, Ospedale
Maggiore-Policlinico
IRCCS, Via F. Sforza 35, Milan, Italy; Tel: 02-55033851, e-mail:
maurizio.moggio@unimi.it
Neurogenic muscle weakness,
Ataxia
and Retinitis Pigmentosa (NARP) and infantile subacute
necrotizing encephalomyopathy
(Maternally Inherited Leigh Syndrome, MILS) are the most severe
clinical
patterns caused by a maternally inherited mitochondrial DNA
(mtDNA) point
mutation at nucleotide position 8993 (ATPase6 gene). We describe
a 27 y.o.
woman (proband) with a 20-year history of slowly progressive
cerebellar
ataxia, fatigability, hearing loss, retinitis pigmentosa,
epileptic seizures
and learning difficulties. Her only sister had died of
undetermined encephalopathy
at age 3 years. The mother presented short stature and distal
limb paresthesia.
Proband’s left biceps
muscle biopsy and Southern blot analysis on skeletal muscle DNA
were normal.
Restriction Fragment Length Polymorphism (RFLP) revealed the
presence of
a mtDNA heteroplasmic T to C base substitution at nucleotide
8993 (88.4%
mutated mtDNA). Blood DNA from the mother revealed the same
mutation (13.2%
mutated mtDNA). Proton magnetic resonance spectroscopy (1H-MRS)
showed
lactate (Lac) increase in the occipital lobe.
So far, few families presenting
the T8993C mutation have been reported, usually with a milder
phenotype
than the more typical T8993G-related cases. In our family, MILS
and NARP
coexist in the same generation, the mother being mildly
symptomatic. 1H-MRS
shows metabolic changes even in clinically unaffected areas.
METABOLIC MUSCLE ADAPTATION TO AEROBIC TRAINING IN PATIENTS AFFECTED BY MITOCHONDRIAL MYOPATHIES
G. Siciliano, S. Tovani, M. Mancuso, L. Pasquali, A. Rocchi, M.L. Manca, L. Murri
Department of Neurosciences, University of Pisa (Italy)
Mutations of mitochondrial DNA at the skeletal muscle level are responsible for insufficient ATP production and deranged metabolism, a main effect of which is represented by abnormal production of lactate. Aim of this study was to evaluate in 10 patients affected by chronic progressive external ophthalmoplegia (CPEO) and large-scale mtDNA rearrangements functional adaptation of skeletal muscle to supervised constant workload 10-week aerobic training, by assessing modifications of anaerobic lactate threshold and relating it to muscle biopsies parameters. A significant decrement (- 36.5%, p<0.01) of exercise lactate levels after training was observed. The training-related decrement in exercise peak lactate correlated with cytochrome c oxidase (COX) enzyme activity (r = - 0.84, p < 0.05), the number of COX- (r = 0.75, p < 0.05) and ragged red fibers (r = 0.68, p = 0.05). On the contrary, no relation was found with the amount of deleted mtDNA in muscle biopsy. These results indicate that aerobic training can be beneficial also in those CPEO patients more severely affected by mitochondrial dysfunction. The level of COX activity in muscle biopsy rather than the amount of mutated mtDNA seems to be a useful predictor for the effectiveness of aerobic training program, suggesting some gene expression mechanisms in mediating muscle adaptation to training itself in these patients.
INTELLECTUAL IMPAIRMENT in DUCHENNE MUSCULAR DYSTROPHY. PART II
C. Solimene, l. Passamano, A. Palladino, A. Salzano and L. Politano
Dipartimento di Internistica Clinica e Sperimentale “F. Magrassi” - Sezione di Cardiomiologia e Genetica Medica - 2nd Naples University
In a previous study,
investigating
the frequency of the mental retardation in Duchenne patients, we
found
no correlation with nor the genetic defects nor the severity of
the disease.
In contrast with previous reports, a verbal intelligence
quotient (VIQ)
higher than the performance intelligence quotient (PIQ) was
observed in
58.8% of the cases. Aims of the study were to support this
result enlarging
the sample size and investigate the distribution of patients on
the normality-mental
retardation axis. IQ was evaluated using the WISC-R and the
intellectual
impairment diagnosed according to the DSMIV. The results
confirmed that
VIQ was higher than PIQ in 58.1% (mean difference 14.1); on the
contrary,
PIQ>VIQ was observed in 34.9% (mean difference 8.6, not
significant according
to the WISC). Concerning the distribution on the normality axis,
a higher
percentage of “normal patients” was observed
evaluating
VIQ, compared with PIQ. These data confirm that a major role in
the diagnosis
of mental retardation of Duchenne patients could be played by
the involvement
of the fine hand movements (influencing the time of the
performance tests
and then the final IQ).
Obviously, a common strategy of
analysis of the patients and tests will provide definitive
conclusions
on this aspect of Duchenne Dystrophy.
R. Sposito, R. Tupler*, L. Pasquali, M.L. Manca, D. Micheli, G. Siciliano, L. Murri
Department of Neuroscience, University of Pisa and *Department of Genetics, University of Pavia (Italy)
Facio-scapulo-humeral muscular
dystrophy
(FSHD) is an autosomal-dominant, inherited disorder, with almost
complete
penetrance, characterized by a slowly progressive course.
However, clinical
appearance can be quite variable, with respect to age at onset,
severity
and pattern of muscle involvement, both between and within
families and
asymptomatic cases are found in about 30% of the patients. For
this reason
diagnosis of FSHD can be sometimes difficult and molecular
diagnosis is
therefore necessary. The latter is at present time based on the
detection
of large deletions of variable size of kpnI repeat units on
chromosome
4q35. A molecular genetics-based epidemiological investigation
was carried
out in 2000 to calculate prevalence rate of FSHD in the
territory of North-West
Tuscany, central Italy, an area covering 6597 km2, with a
population nearly
of 1300000 inhabitants. Results have been compared to those of a
previous
study conducted in the same area in 1981, in the pre-molecular
era.
We found a prevalence of 3,16 x
10000 inhabitants, a value two times as higher than that found
in our previous
study. Genotype-phenotype relationships were assessed in order
to characterize
mildly and severely affected patients. This results confirm the
usefulness
of routine adoption of the molecular genetics-based screening to
be extensively
applied to make correct diagnosis of FSHD.
Structural alterations of
collagen
type VI in skin fibroblast cultures from patients affected by
Ullrich syndrome.
S. Squarzoni 1, P. Sabatelli1,
E.
Mattioli2, M. Columbaro2, L. Merlini2, P. Guicheney3, E. Demir3,
E. Bertini4,
G. Pepe5, H. Topaloglu7and N.M. Maraldi1,6
1 Istituto di Citomorfologia
Normale
e Patologica, CNR c/o IOR, Bologna, Italy, 2 Laboratorio di
Neurofisiopatologia,
IOR, Bologna, Italy, 3 INSERM UR 523, Institut de Myologie,
Paris, France,
4 Divisione di Neurologia Pediatrica, Unità di Medicina
Molecolare,
Osp.Bambino Gesù, Roma, Italy, 5 Università di Roma Tor Vergata,
dip. di Medicina Interna, Roma, Italy, 6 Laboratorio di Biologia
Cellulare,
IOR, Bologna , Italy, and 7 Hacettepe Children’s
Hospital, Ankara,
Turkey
Ullrich congenital muscular
dystrophy
is caused by recessive mutations in collagen VI gene (Camacho et
al. PNAS
2001, in press). Collagen VI is widely expressed in the
extracellular-matrix
of skin cultured fibroblasts: monomers are assembled inside the
cytoplasm
in tetramers and secreted to form fibrillar networks connecting
the extracellular-matrix
and membrane receptors. We evaluated by immunofluorescence and
immunoelectron
microscopy the amount and organization of secreted collagen VI
of cultured
skin fibroblasts from 6 patients carrying mutations on COL6
genes.
Immunofluorescence showed
absence
of collagen VI in 4 patients, while in the other 2 appeared
strongly reduced.
Immunoelectron microscopy in the latter 2 cases revealed
inability to constitute
fibrils or well developed networks. The interactions with the
other proteins
were also affected and some isolated collagen VI deposits showed
a rolled
shape. To evaluate if reduced expression or secreted mutated
protein may
affect the collagen VI organization, we analyzed fibroblast
cultures from
a Bethlem patient with haploinsufficiency. Immunofluorescence
analysis
of collagen VI showed a reduced expression of secreted protein
comparable
with the Ullrich patients while the ultrastructural organization
appeared
normal. Our findings suggest that immunofluorescence analysis
may help
to identify quantitative defects, while electron microscopy may
give insight
about the fate of the mutated protein.
A. Tessa, M.A.B. Melone, F.M. Santorelli*, G. Lus, and R. Cotrufo
Division of Neurology,
Department
of Neurological Sciences - Second University of Naples,
*Molecular Medicine
Department - Hospital Bambin Gesù, Roma
e-mail: marina.melone@unina2.it
Mitochondrial encephalomyopathies are heterogeneous disorders associated with mutations in the nuclear or in the mitochondrial DNA (mtDNA). We identified a family in which a 20-years-old man developed a severe disorder resembling MELAS (mitochondrial encephalomyopathy, lactic acidosis, stroke-like episodes). His mother had died of a stroke-like attack in young age. In muscle biopsy of our patient, we identified high percentages of a novel tRNAHis mutation (T12417G). The mutation fulfilled accepted criteria for pathogenicity. The mutation was less abundant in the proband’s peripheral blood and it was not detected in hairy roots or blood from seven maternal relatives who complained of either migraine without aura or tension headache. In microdissected skeletal muscle fibers from the proband a lower rate of ATP production was shown, respect to control cell lines. Reporting the first mutation in the tRNAHis gene associated with mitochondrial encephalomyopathy, our data expand the genetic variants associated with MELAS.
A case of distal myopathy with
preminent
involvement of gastrocnemious muscle and rimmed vacuoles
G. Tomelleri, M. Filosto, C.
Baronchelli*,
G. Vattemi, P. Tonin
Dipartimento di Scienze
Neurologiche
e della Visione, Sez. di Neurologia clinica, Policlinico G.B.
Rossi, Università
di Verona. * Dipartimento di Anatomia Patologica, Spedali Civili
di Brescia
Among the early adult onset
distal
myopathies of lower limbs, a form with preferential involvement
of anterior
tibial muscle and rimmed vacuoles in muscle biopsies (Nonaka
type distal
myopathy) and a form with predominant involvement of
gastrocnemious muscle
and dystrophic change in muscle biopsy (Miyoshi type distal
muscle dystrophy)
were described. We report a sporadic case affected by early
adult onset
distal myopathy with preminent involvement of gastrocnemious and
consequent
impossibility in standing of the toes. S-CK was increased more
than 10
times the upper normal limit. On EMG a neurogenic pattern was
recorded.
A first muscle biopsy obtained from vastus lateralis muscle
showed small
group of atrophic angulated fibers suggesting a neurogenic
atrophy. In
a second biopsy, obtained from the gastrocnemious, peculiar
myopathic change
were found: rimmed vacuoles in many fibers and numerous
structural abnormalities
i.e. core-target formation; excessive variation in fiber size,
necrotic
fibers and increased endomisial connective tissue were present
too. The
authors discuss the clinical and pathological findings in
relation to other
cases with lower limb distal myopathy.
SKELETAL MUSCLE LIPID STORAGE AND MITOCHONDRIAL BETA-OXIDATION
A. Toscano, M. Aguennouz, C. Rodolico, A. Ciranni, M. Autunno, O. Musumeci, G. Vita
Department of Neuroscience, Psychiatry and Anesthesiology, University of Messina
Inborn errors of the
mitochondrial
beta-oxidation of long chain fatty acids represent an evolving
field of
inherited metabolic diseases. The most frequent defects of the
beta-oxidation
affect the activities of short-chain acyl coenzyme A
dehydrogenase (SCAD),
medium chain acyl CoA dehydrogenase (MCAD), and long chain acyl
CoA dehydrogenase
(LCAD). The clinical phenotype of fatty acid oxidation disorders
include
disease affecting one or more of the fatty acid-metabolizing
tissues and
can vary considerably.
We have reviewed the clinical
and
biochemical data of 23 patients, admitted to our Center for
Neuromuscular
Disorders in the last 5 years, that showed a skeletal muscle
lipid storage
and defects of beta-oxidation. The clinical presentation greatly
varied:
myalgias and cramps, iperckemia, diffuse myopathy,
encephalomyopathy or
neuropathy. Among them we have found: 4 pts with multiple acyl
coenzyme
A dehydrogenases deficiency (MAD), 4 pts with a combined defect
of LCAD
and MCAD, 2 pts with LCAD and SCAD deficiency, 1 pt with MCAD
and SCAD
defect and 12 other pts with an isolated defect with prevalence
of MCAD
deficiency. Administration of oral riboflavin to pts with MAD
resulted
in a prompt clinical recovery, but also 5 pts with different
combination
of enzyme deficiencies manifested a striking clinical
improvement.
S. Tovani, M. Mancuso, D. Tedeschi, V. Lombardi, A. Rocchi, A. Del Corona, B. Solito, G. Siciliano
Department of Neuroscience, Neurological Clinics, University of Pisa, Italy
Although causative mutation of
Steinert’s
Myotonic Dystrophy (DM) is recognized as a CTG trinucleotide
expansion
on 19q.13.3, pathogenic mechanisms of multisystem involvement of
DM are
still under debate. It has been suggested that mitochondrial
abnormalities
can occur in this disease and deficiency of coenzyme Q 10
(CoQ10) has been
considered one possible cause for this. Aim of this
investigation was to
evaluate CoQ10 blood levels in DM patients and relate them to
the degree
of CTG expansion as well as to the amount of lactate production
in exercising
muscle as indicator of mitochondrial dysfunction.
Plasma total CoQ10 levels were
determined
by RP-HPLC-UV in 35 DM patients. In selected patients blood
lactate kinetics
during incremental exercise performed on an electrically braked
pedal-rate
bicycle ergometer. CoQ10 concentrations appeared significantly
reduced
with respect to normal controls: 0.84 ± 0.25 vs 1.58 ± 0.28
µg/ml (p < 0.05). Blood lactate was significantly higher than
controls (p < 0,05) both in resting conditions (2.9±0.55 vs
1.44
± 1.1 mmol/l) and at its exercise peak (6.87 ± 1.74 vs 4.9
± 0.6 mmol/l), while lactate threshold was anticipated (30-50%
vs
60-70%, p < 0.05). CoQ10 levels significantly inversely
correlated with
CTG expansion degree and lactate values at threshold level (p
< 0.05).
Our data indicate the
occurrence
of reduced CoQ10 levels in DM, possibly related to disease
pathogenic mechanisms
associated to abnormal CTG trinucleotide amplification.
CARDIAC INVOLVEMENT IN FACIOSCAPULOHUMERAL MUSCULAR DYSTROPHY: A CORRELATION WITH THE 4q35 DELETION IN 54 PATIENTS
C.P. Trevisan1, E. Pastorello1, M.T. Rigoni1, M. Armani1, C. Angelini1, R. Tupler2, G. Galluzzi3, M.L. Mostacciuolo4, M. Zortea4
1 Department of Neurology, University of Padua; 2 Department of Biology, University of Pavia; 3 Institute of Cell Biology-CNR, Rome; 4 Department of Biology, University of Padua
Facioscapulohumeral Muscular
Dystrophy
(FSHD) is usually associated with deletion of a DNA fragment
(q35) on chromosome
4. Extensive studies on the natural history of 4q35 FSHD are
lacking and
little information is available about the involvement of the
extra-muscular
tissues, in particular of heart. We studied 54 FSHD patients (31
males
and 23 females, with a mean age of 44 years) diagnosed according
to the
criteria of the European Consortium of FSHD. For all of them, we
evaluated
the clinical history and the muscular deficit (MRC scale and
four functional
tests); moreover, possible heart involvement was assessed by
clinical examination,
surface ECG, 24-hour ECG and echocardiography. The size of the
4q35 deletion
was evaluated by Southern blot analysis of genomic DNA digested
by EcoRI
e BlnI and by the p13E-11 probe. Overt cardiac involvement was
evident
in 3 of our patients (ischemic alterations, cardiac failure and
paroxysmal
tachycardia), while 24-hour ECG detected subclinical conduction
defects
or arrhythmia in 11 of the 54 patients. The size of the deleted
4q35 fragment
ranged between 15 to 27 Kb. The size of this fragment was not
correlated
with the parameters of the heart involvement.
On the whole, our clinical
study
showed that symptomatic heart disease is an unusual feature of
FSHD, while
subclinical cardiac arrhythmia may be detected in 20% of
patients; no correlation
was evident with the size of the deleted 4q35 fragment.
Facioscapulohumeral muscular
dystrophy
(FSHMD) presenting with lower limb monomelic atrophy
A. Uncini, A. Di Muzio, E.
Ricci*,
C. Scoppetta°, G. Galluzzi^, S. Servidei*
Centro per le Malattie
Neuromuscolari,
Università “G. d’ Annunzio, Chieti, and
*Istituto
di Neurologia, Università Cattolica, °Clinica Malattie Nervose
e Mentali, Università “La Sapienza”,
^Istituto
di Biologia Cellulare CNR, Roma.
FSHD has a distinctive
distribution
but may be markedly asymmetric and extremely variable in extent
of involvement
and severity. A 28-year-old woman presented with left leg
atrophy. Examination
showed marked wasting of left triceps surae and impossibility to
walk on
left toes. There was no weakness of facial and all other muscles
nor scapular
winging. Deep tendon reflexes were hypoactive except absent left
ankle
jerk. CK was 424 U/L (normal <260 U/L). EMG of left
gastrocnemii showed
electrical silence in some areas, spontaneous activity and few
low amplitude
motor units at maximal effort in other areas. EMG of left
tibialis anterior
was myopathic. Muscular CT scan showed confluent areas of
decreased density
in left gastrocnemii and soleus and right gastrocnemius medialis
muscle.
Shoulder, mid-arm, pelvic and mid-thight scans were normal.
Muscle biopsy
(right gastrocnemius lateralis) showed increased fiber size
variability,
numerous small, grouped, angulated fibers, and type 2 fiber
prevalence.
Familiar history was negative but the 60-year-old father showed
slight
weakness of orbicularis oculi and some difficulty to walk on
heels. CK
was normal and EMG myopathic. The 30-year-old brother was normal
at examination
but had increased CK (700 U/L). DNA analysis showed the 4q35
deletion in
all three family members.
This family confirms the wide
intrafamiliar
variability of FSHD and the proband broadens the phenotypic
spectrum of
FSHD presentation.