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| Si riporta
di seguito un'ampia bibliografia riguardante lo stato d'arte
scientifico in merito alla leucodistrofia di Krabbe. Sono
state selezionale le pubblicazioni scientifiche più
significative e recenti.... |
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D.ssa Pannuzzo Giovanna. Per qualsiasi dubbio e/o approfondimento
la D.ssa Pannuzzo rimane a vostra completa disposisizone  email:[email protected]
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Am
J Hum Genet. 1990 Jul;47(1):37-44. |
Krabbe
disease locus mapped to chromosome 14
by genetic linkage. |
| Zlotogora
J, Chakraborty S, Knowlton RG, Wenger
DA. |
| Department
of Biochemistry and Molecular Biology,
Jefferson Medical College, Philadelphia,
PA 19107. |
|
Using
genetic linkage we have localized the
gene coding for galactocerebrosidase
(GALC) to human chromosome 14. Patients
with Krabbe disease and their family
members were assayed for GALC activity
in leukocytes or fibroblasts and were
classified as affected, carrier, noncarrier,
or unknown. Polymorphic DNA markers
from chromosome 14 demonstrated a multipoint
LOD score of 3.40 with GALC located
13 cM centromere distal to CRI-C70 (D14S24).
This finding is consistent with the
location of the mouse twitcher mutation
(a model of human GALC deficiency) on
chromosome 12, which has substantial
homology to human chromosome 14. Our
data do not support a previous report's
localization of GALC to chromosome 17. |
|
Tale
pubblicazione riguarda la localizzazione
del gene che codifica per la galattosilcerebrosidasi.
Questa localizzazione è stata
individuata sul cromosoma umano 14. |
|
| Molecular
mechanism of psychosine-induced cell death
in human oligodendrocyte cell
line. |
|
Haq E, Giri
S, Singh I, Singh AK.
|
| Department
of Pediatrics, Medical University of
South Carolina, USA. |
| This
study delineates the molecular mechanism
underlying psychosine-induced oligodendroglial
cell death. An immortalized human oligodendroglial
cell line, MO3.13, was treated with
exogenous psychosine (beta-galactosylsphingosine),
a toxic metabolite that accumulates
in the tissues of patients with Krabbe's
disease. The mode of cell death induced
by psychosine was found to be apoptotic,
as revealed by different apoptotic markers
viz., TUNEL, DNA fragmentation and caspase
cleavage/activation. The action of psychosine
was redox sensitive, as measured by
changes in mitochondrial membrane potential
(psidelta), and this effect of psychosine
could be reversed by pre-treatment with
the antioxidant molecules N-acetyl-l-cysteine
or pro-cysteine. Psychosine directly
affects the mitochondria as revealed
by the activation of caspase 9 but not
caspase 8. Up-regulation of the c-jun/c-jun
N-terminal kinase pathway by psychosine
leads to the induction of AP-1 and,
at the same time, psychosine also down-regulates
the lipopolysaccharide-induced NF-kappaB
transactivation. These observations
indicate that the mechanism of action
of psychosine is, through the up-regulation
of AP-1, a pro-apoptotic pathway as
well as, through the down-regulation
of the NF-kappaB pathway, an antiapoptotic
pathway. |
|
Questo
studio riguarda il meccanismo molecolare
attravero il quale la psicosina esercita
il suo effetto tossico. L’apoptosi
avviene tramite attivazione della caspasi
9, con sovraregolazione di AP-1(un meccanismo
che favorisce l’apoptosi) e sottoregolazione
del NF-KappaB(fattore neurotrofico),
che è antiapoptotico. |
|
| Innherit
Metab DIis. 1999 Apr;22(2):155-62. |
| Molecular
heterogeneity of Krabbe disease. |
| Fu
L, Inui K, Nishigaki T, Tatsumi N, Tsukamoto
H, Kokubu C, Muramatsu T, Okada S. |
| Department
of Pediatrics, Faculty of Medicine, Osaka
University, Japan. [email protected] |
Krabbe
disease (globoid cell leukodystrophy)
is an autosomal recessive neurodegenerative
disorder that affects both the central
and peripheral nervous system due to
an enzymatic defect of galactocerebrosidase
(GALC). Following its cloning, many
mutations in the galactocerebrosidase
gene have been reported, but the correlation
between phenotype and genotype was not
clear in many cases. In this study we
further investigated the molecular defects
in another 10 patients (6 Japanese and
4 non-Japanese), using cultured skin
fibroblasts, and found 10 mutations,
of which 8 were novel, including a nonsense
mutation (W647X) and 7 missense mutations
(G43R, S52F, T262I, Y319C. W410G, R515H,
T652R) in the coding region. Some phenotype-specific
mutations were found but the other mutations
were private. Mutations reported so
far have been distributed over the whole
GALC gene and it is difficult to speculate
on functional domains of the GALC protein
and phenotypically specific regions |
|
In
questo studio sono state studiate le
mutazioni del gene della galattosilcerebrosidasi
allo scopo di trovare una correlazione
tra il fenotipo e il genotipo. Sono
stati valutati 10 pazienti (6 giapponesi
e 4 non giapponesi) e sono state trovate
10 mutazioni, delle quali 8 nuove, una
non senso e 7 missenso nella regione
codificante. |
|
| Mol
Genet Metab. 2000 May;70(1):1-9. |
| Krabbe
disease: genetic aspects and progress
toward therapy. |
| Wenger
DA, Rafi MA, Luzi P, Datto J, Costantino-Ceccarini
E. |
| Department
of Neurology, Thomas Jefferson University,
Philadelphia, PA 19107, USA. |
| Krabbe
disease or globoid cell leukodystrophy
is a disorder involving the white matter
of the peripheral and central nervous
systems. Mutations in the gene for the
lysosomal enzyme galactocerebrosidase
(GALC) result in low enzymatic activity
and decreased ability to degrade galactolipids
found almost exclusively in myelin.
The pathological changes observed, including
the presence of globoid cells and decreased
myelin, appear to result from the toxic
nature of psychosine and accumulation
of galactosylceramide that cannot be
degraded due to the GALC deficiency.
Over 60 mutations have been identified
in this gene. The great majority are
disease-causing; however, a few are
considered polymorphisms. While most
patients present with symptoms within
the first 6 months of life, others present
later in life including adulthood. Even
patients with the same genotype can
have very different clinical presentations
and course. The reason for this is not
known. Treatment at this time is limited
to hematopoietic stem cell transplantation
that appears to slow the progression
of the disease and improve the magnetic
resonance images. Studies using stem
cells and viral vectors to transduce
transplantable cells are under way in
model systems. In culture, oligodendrocytes
from the twitcher mouse model can assume
a normal appearance after differentiation
if GALC activity is provided via viral
transduction or uptake from donor cells.
Therefore continued myelination and/or
remyelination in patients will require
supplying GALC activity by transplanted
cells or viral vectors to still functional
endogenous oligodendrocytes or transplantation
of normal oligodendrocytes or stem cells
that can differentiate into oligodendrocytes.
Using the animal models these options
can be explored. Copyright 2000 Academic
Press. |
|
| Tale
studio riguarda lo stato d’arte
delle possibilità terapeutiche
di intervento nella leucodistrofia di
Krabbe. In particolare, si parla del
trapianto di cellule staminali e dello
studio di vettori virali in vari modelli.
In coltura cellulare, gli oligodentrociti
assumono un aspetto normale dopo la
differenziazione, se l’attività
del GALC (l’enzima galattosilcerebrosidasi)
viene fornita tramite traduzione virale
o mediante cellule di un donatore |
|
J
Child Neurol. 2003 Sep;18(9):595-603.
|
Globoid
cell leukodystrophy (Krabbe's disease):
update. |
Suzuki
K. |
Neuroscience
Center, Department of Neurology, University
of North Carolina School of Medicine,
Chapel Hill, NC, USA. [email protected] |
The
classic globoid cell leukodystrophy
(Krabbe's disease) is caused by genetic
defects in a lysosomal enzyme, galactosylceramidase.
It is one of the two classic genetic
leukodystrophies, together with metachromatic
leukodystrophy. The mode of inheritance
is autosomal recessive. Typically, the
disease occurs among infants and takes
a rapidly fatal course, but rarer late-onset
forms also exist. Clinical manifestations
are exclusively neurologic with prominent
white-matter signs. The pathology is
unique, consisting of a rapid and nearly
complete disappearance of myelin and
myelin-forming cells--the oligodendrocytes
in the central nervous system and the
Schwann cells in the peripheral nervous
system, reactive astroytic gliosis,
and infiltration of the unique and often
multinucleated macrophages ("globoid
cells") that contain strongly periodic
acid-Schiff (PAS)-positive materials.
A normally insignificant but highly
cytotoxic metabolite, galactosylsphingosine
(psychosine), is also a substrate of
galactosylceramidase and is considered
to play a critical role in the pathogenesis.
The galactosylceramidase gene has been
cloned, and a large number of disease-causing
mutations have been identified. Equivalent
genetic galactosylceramidase deficiency
occurs in several mammalian species,
such as mouse, dog, and monkey. Recently,
deficiency of one of the sphingolipid
activator proteins, saposin A, was demonstrated
to cause a late-onset, slowly progressive
globoid cell leukodystrophy at least
in the mouse, with all of the phenotypic
consequences of impaired degradation
of galactosylceramidase substrates.
Human globoid cell leukodystrophy owing
to saposin A deficiency might be anticipated
and should be suspected in human patients
with a late-onset leukodystrophy with
normal galactosylceramidase activity
when other possibilities are also excluded.
The only serious attempt at treating
human patients is bone marrow transplantation,
which can provide significant alleviation
of symptoms, particularly in those patients
with later-onset, more slowly progressive
globoid cell leukodystrophy.
|
|
| Qui
viene inquadrata in modo generale la
leucodistrofia di Krabbe. Si tratta
di una malattia genetica autosomica
recessiva, causata dal difetto enzimatico
della galattosilcerebrosidasi, che comporta
la rapida scomparsa della mielina, con
morte di oligodentrociti nel sistema
nervoso centrale e di cellule di schwann
nel sistema nervoso periferico, e infiltrazione
di macrofagi multinucleati (cellule
globoidi). Il metabolica tossico responsabile
della patogenesi della malattia è
la psicosina (galattosilsfingosina).
Recentemente è stata inquadrata
una leucodistrofie causata da deficienza
di saposina A, con attività normale
della galattosilcerebrosidasi. |
|
Neurosci
Lett. 2004 Apr 1;358(3):205-9. |
Psychosine-induced
apoptosis in a mouse oligodendrocyte
progenitor cell line is mediated by
caspase activation. |
Zaka
M, Wenger DA.
|
Department
of Neurology, 1020 Locust Street, Room
394, Jefferson Medical College, Philadelphia,
PA 19107, USA.
|
Globoid
cell leukodystrophy (GLD) is an inherited
neurological disorder caused by the
deficiency of galactocerebrosidase (GALC)
activity resulting in cell death of
oligodendrocytes and subsequent demyelination.
The death of oligodendrocytes is accompanied
by accumulation of psychosine, which
is also a substrate for the GALC enzyme.
In this report, we investigated the
mechanism of the toxic effect of psychosine
in a mouse-derived oligodendrocyte progenitor
cell line (OLP-II), a precursor to the
cell type most affected in GLD. Psychosine
caused cytotoxicity in a dose-dependent
manner. Lower concentration of psychosine
(5 microM) did not significantly reduce
OLP-II cell numbers. However, 50 microM
psychosine induced up to 45% cell death.
These results were confirmed by the
Tunel assay, which is a hallmark for
the detection of apoptosis. Moreover,
psychosine treatment resulted in the
activation/cleavage of initiator caspase-8
and -9, and effector caspase-3. These
results support a role for psychosine
in OLP-II cell death via an apoptotic
mechanism, and suggest the involvement
of caspases. |
|
In
questa pubblicazione viene valutato
il meccanismo attraverso il quale si
verifica l’effetto tossico della
psicosina. In particolare, 50 microM
di psicosina inducono circa il 45% di
morte cellulare, attraverso l’attivazione
degli iniziatori caspasi 8 e 9, e dell’effettore
caspasi 3. |
|
Gene
Ther. 2004 Aug;11(15):1188-94. |
Transgenic
rescue of Krabbe disease in the twitcher
mouse. |
De
Gasperi R, Friedrich VL, Perez GM, Senturk
E, Wen PH, Kelley K, Elder GA, Gama
Sosa MA. |
Department
of Psychiatry, Mount Sinai School of
Medicine of New York University, New
York, NY, USA. |
| The
twitcher mouse is a natural model of
Krabbe disease caused by galactocerebrosidase
(GALC) deficiency. Previous attempts
at rescuing the twitcher mouse by bone
marrow transplantion, viral transduction,
or transgenesis were only partially
successful. Here, we report the transgenic
(tg) rescue of the twitcher mouse with
a BAC clone harboring the entire GALC.
The twi/twi/hGALC tg mice exhibited
growth, motor function, and fertility
similar to those of nonaffected animals.
These animals had normal levels of GALC
activity in brain and were free of the
typical twitcher demyelinating pathology.
Surprisingly, GALC expression in twi/twi
hGALC tg kidneys was low and galactocerebroside
storage was only partially cleared.
Nonetheless, these mice have been maintained
for over 1 year without any sign of
disease. Since pathological damage associated
with GALC deficiency is confined to
the nervous system, our work represents
the first successful rescue of the twitcher
mouse and opens the possibility of developing
novel therapeutic approaches.
|
|
Questo
studio riguarda la trasduzione genica
di un modello di topo twitcher con un
clone BAC che contiene l’intero
GALC. Tali animali avevano livelli normali
dell’enzima
e non mostravano la tipica patologia
da demielinizzazione. |
|
| Ned
Tijdschr Geneeskd. 2004 Apr 24;148(17):826-8.
|
[From
gene to disease; Krabbe disease and
galactosylceramidase deficiency] |
Kleijer
WJ, van Diggelen OP, Halley DJ, van
der Ploeg AT, Mancini GM. |
Afd.
Klinische Genetica, Erasmus Medisch
Centrum, Postbus 1738, 3000 DR Rotterdam.
[email protected] |
| Krabbe
disease is a devastating lysosomal storage
disease with autosomal recessive
inheritance. Early symptoms
of leukodystrophy, such as irritability
and hypertonicity, appear at 3 to 6
months of age, but progress rapidly
to severe mental and motor deterioration
and death in the second year. The disease
is caused by the deficiency of the lysosomal
enzyme galactosylceramidase, which is
in turn caused by mutations in the GALC
gene. The incidence of the infantile
form of the disease in the Netherlands
is estimated at 1.3 per 100,000 births;
50% of the patients' alleles show the
large 30-kb deletion. Early diagnosis
by enzyme assay in leukocytes or skin
fibroblasts permits timely genetic counselling
and prenatal diagnosis, which is reliably
made by enzyme or mutation analysis
in the chorionic villi. |
|
Tale
pubblicazione presenta la leucodistrofia
di Krabbe come una malattia lisosomiale
, ereditaria autosomica recessiva. I
sintomi iniziali sono irritabilità
e ipertonia, in genere tra i 3 e i 6
mesi di vita. Progredisce rapidamente
con severo deterioramento mentale e
motorio fino alla morte nel secondo
anno di vita. L’incidenza in Olanda
è stimata a 1.3 per ogni 100,000
nascite. È possibile la diagnosi
prenatale. |
|
| Neurochem
Res. 1999 Feb;24(2):287-93. |
| Transduction
of cultured oligodendrocytes from normal
and twitcher mice by a retroviral vector
containing human galactocerebrosidase
(GALC) cDNA. |
| Costantino-Ceccarini
E, Luddi A, Volterrani M, Strazza M,
Rafi MA, Wenger DA. |
| Centro
Studio Cellule Germinali, Siena, Italy. |
| Krabbe
disease or globoid cell leukodystropy
is a lysosomal disorder caused by a
deficiency of galactocerebrosidase (GALC)
activity. This results in defects in
myelin that lead to severe symptoms
and early death in most human patients
and animals with this disease. With
the cloning of the GALC gene and the
availability of the mouse model, called
twitcher, it was important to evaluate
the effects of providing GALC via a
retroviral vector to oligodendrocytes
in culture. After differentiation, the
untransduced cells from normal mice
extended highly branched processes while
those from the twitcher mice did not.
Oligodendrocytes in culture can be readily
transduced to produce much higher than
normal levels of GALC activity. Transduced
normal and twitcher cells formed clusters
when plated at high density. Transduction
of twitcher oligodendrocytes plated
at lower density, followed by differentiation,
resulted in some cells having a completely
normal appearance with highly branched
processes. Other cells showed retraction
and fragmentation. Perhaps over expression
of GALC activity may be detrimental
to oligodendrocytes. These studies demonstrate
that the phenotype of twitcher oligodendrocytes
can be corrected by providing GALC via
gene transfer, and this could lead the
way to future studies to treat this
disease. |
|
|
| Qui
si valutano gli effetti su colture di
oligodentrociti a cui viene fornito
GALC tramite un retrovirus. La trasduzione
di oligodentrociti di modelli twitcher,
a bassa densità, è seguita
da differenziazione e risulta in cellule
che hanno un aspetto completamente normale.
Altre cellule mostrano frammentazione. |
|
Neurobiol
Dis. 2001 Aug;8(4):600-10. |
Retrovirus-mediated
gene transfer and galactocerebrosidase
uptake into twitcher glial cells results
in appropriate localization and phenotype
correction. |
Luddi
A, Volterrani M, Strazza M, Smorlesi
A, Rafi MA, Datto J, Wenger DA, Costantino-Ceccarini
E. |
Centro
Studio Cellule Germinali, Consiglio
Nazionale delle Ricerche, Via Pendola
62, Siena Italy, 53100. |
Galactocerebrosidase
(GALC) is deficient in all tissues from
human patients and animal models with
globoid cell leukodystrophy (GLD) or
Krabbe disease. The deficiency results
in decreased lysosomal catabolism of
certain galactolipids including galactosylceramide
and psychosine that are synthesized
maximally during myelination. According
to current theories, the accumulation
of psychosine in humans and animals
with GLD induces oligodendrocyte degeneration
and myelination ceases. Transduction
of oligodendrocytes from twitcher mice
with a retroviral vector containing
the GALC cDNA can correct the enzyme
deficiency in these cells. Our data
show that twitcher astrocytes and oligodendrocytes
can internalize exogenous GALC, as well
as donate the enzyme to the mutant glial
cells. Antibodies against human GALC
localized the GALC antigen in retrovirally
transduced cells and cells receiving
enzyme via cell to cell secretion and
uptake to the lysosomal fraction. In
fact immunocytochemical studies in transduced
oligodendrocytes revealed that the GALC
colocalizes in vesicles lysosomal-associated
membrane protein-2 (LAMP2) (+). Moreover,
labeling cells with anti-GALC and a
marker for oligodendrocytes demonstrated
that, upon differentiation, transduced,
twitcher oligodendrocytes attained the
normal branched process configuration,
while untransduced cells show only abnormal
morphology. Phenotype correction in
mutant oligodendrocytes has also been
observed after enzyme transfer. These
studies indicate that GALC activity
supplied to cultured oligodendrocytes
from twitcher mice by different methods
can correct the pathological phenotype
of these cells. Copyright 2001 Academic
Press.
|
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Anche
tale studio riguarda la trasduzione
degli oligodentrociti di topo twitcher
con GALC cDNA. Viene vista l’internalizzazione
dell’enzima esogeno all’interno
degli astrociti e degli oligodentrociti,
con una correzione del fenotipo. |
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Purtroppo
oggi poche persone sono a conoscenza della malattia
denominata Leucodistrofia di Krabbe.... Una malattia
terribile che degenera irremediabilmente il sistema
nervoso sino a portare alla morte dell'individuo.Aiutaci
a divulgare questo messaggio, tutti assieme possiamo
lottare e dare una speranza in più a tanti bambini
che come Grazia soffrono... |
Intellisystem Technologies è coinvolta a pieno titolo nel Progetto
Grazia e rende disponibile la propria tecnologia, prodotti
e soluzioni al servizio di tutti coloro che ne possono
trarre vantaggio contribuendo alla Ricerca Scientifica
per lo studio di nuove terapie contro la Leudostrifoia
di Krabbe... |
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