Clinical heterogeneity in Italian patients with amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a rare and devastating neurodegenerative disorder. The majority of cases are sporadic ALS (SALS), with 5-10% being familial ALS (FALS), and are inherited mostly as autosomal dominant. Mutations in Cu/Zn superoxide dismutase (SOD1) and the TAR DNA-binding protein (TARDBP) gene are the most commonly known cause of ALS. We analyzed these genes in 61 Italian ALS patients using high-resolution melting analysis to confirm the role of SOD1 and TARDBP in the physiopathology of ALS. The screenings showed a single mutation in SOD1 (Asp109Tyr) and three in TARBDP (Ala382Thr, Gly295Ser, Gly294Val) in five unrelated ALS patients. This report enlarges the spectrum of clinical phenotypes associated with genetic mutations in SOD1 and TARDBP genes confirming the variability of phenotypes associated with the same mutation and emphasizes the importance of genetic analysis. The different genotype-phenotype correlations suggest the implication of other factors possibly influencing clinical manifestation of the disease, such as an epigenetic or epistatic effect with other genes not yet identified.

Clinical and genetic analysis of hereditary and sporadic ataxia in central Italy.

We have clinically and genetically evaluated 24 affected patients belonging to 22 Italian Friedreich ataxia (FA) families, 52 patients from 32 kindreds with proven autosomal dominant cerebellar ataxia (ADCA), 9 patients belonging to 5 families with autosomal recessive hereditary ataxia (ARCA) and 103 sporadic cases, 89 of which affected by idiopathic late onset cerebellar ataxia (ILOCA). Genotype-phenotype correlation analyses in FA patients have evidenced an inverse relationship between GAA repeat expansion length and age of onset, disease duration, and presence of cardiomyopathy. Among autosomal dominant types, spinocerebellar ataxia 2 (SCA2) genotype has been found in 31% of our ADCA families, resulting the most frequent form of ataxia. Phenotypic analysis of the various SCA subtypes evidenced a marked heterogeneity of symptoms with a substantial overlap between different syndromes.

Spontaneous and induced chromosome damage in somatic cells of sporadic and familial Alzheimer's disease patients.

Alzheimer's disease (AD) is a neurodegenerative disorder of the elderly with a complex etiology due to the interaction between genetic and environmental factors. At least 15% of cases are inherited as an autosomal dominant mutation, but the majority are sporadic. We evaluated cytogenetic alterations, both spontaneous and chemical-induced [aluminium (Al) and griseofulvin (GF)], by means of the micronucleus (MN) test in lymphocytes or skin fibroblasts of 14 patients with sporadic and eight with familial Alzheimer's disease (FAD), respectively. The spontaneous MN frequencies of sporadic (20.8 +/- 9.2) and familial (20.7 +/- 4.6) AD patients are significantly higher than those of the respective control groups (9.0 +/- 6.8 and 6.7 +/- 3.4). In all AD patients, GF significantly increased the spontaneous MN frequency of somatic cells to a lesser extent (P < 0.05) as compared with the control group. Al treatment did not induce MN in AD patients. The results of the present study indicate that different types of somatic cells from sporadic and familial AD patients show comparable levels of spontaneous cytogenetic anomalies, and MN induction is partially reduced or lacking according to the type of chemical treatments.

Lack of SOD1 gene mutations and activity alterations in two Italian families with amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a progressive fatal disorder, which results from the degeneration of motor neurons in the brain and spinal cord. Approximately 20% of the inherited autosomal dominant cases are due to mutations within the gene coding for Cu/Zn superoxide dismutase 1 (SOD1), a cytosolic homodimeric enzyme that catalyzes the dismutation of toxic superoxide anion. We investigated the presence of SOD1 gene mutations and activity alterations in two unrelated families of ALS patients from Elba, an island of central Italy. No mutation in SOD1 exon 1 to 5 and no activity alteration were observed in all members of the two analyzed ALS families (FALS). These data show an apparent heterogeneous distribution of ALS patients with SOD1 gene mutations among different populations and suggest that another genetic locus could be involved in the disease.

Music and cerebral hemodynamics.

Previous studies performed by positron emission tomography and Transcranial Doppler (TCD) found a different cerebral activation during musical stimuli in musicians compared to non-musicians. The aim of our study is to evaluate by means of TCD, possible different pattern of cerebral activation during the performance of different musical tasks in musicians, non-musicians and lyrical singers. Our findings show a left hemispheric activation in musicians and a right one in non-musicians. Preliminary data on lyrical singers' activation patterns need further confirmation with a larger population. These data could be related to a different approach to music listening in musicians (analytical) and non-musicians who are supposed to have an emotional approach to music.

Risperidone in idiopathic and symptomatic dystonia: preliminary experience.

Risperidone is a heterocyclic neuroleptic with prominent antiserotoninergic (5HT2) as well as antidopaminergic (D2) activity. We studied the efficacy of risperidone in the treatment of idiopathic and symptomatic dystonias in seven patients using the Fahn and Marsden rating scale for torsion dystonia before and after four weeks of treatment (2-6 mg/day). The twisting and involuntary movements with abnormal postures decreased in all the patients treated, with a statistically significant mean improvement (41%; p = 0.009, CI 95%). Our results suggest that risperidone is useful in idiopathic and symptomatic dystonia.

Gluthatione level is altered in lymphoblasts from patients with familial Alzheimer's disease.

Intracellular levels of glutathione (GSH), glutathione disulphide (GSSG), glutamic acid and gamma-glutamyl cysteine synthetase (gamma-GCS) were measured in lymphoblast lines from patients with familial and sporadic Alzheimer's disease (AD) and from age-matched controls. Lymphoblasts carrying presenilins (PS) and amyloid precursor protein (APP) genes mutations showed significantly decreased GSH content with respect to controls. Levels of GSSG and glutamic acid, as well as the activity of gamma-GCS were not significantly different in lymphoblasts carrying genes mutations as compared with control cells. These results indicate that even peripheral cells not involved in the neurodegenerative process of AD show altered GSH content when carrying PS and APP genes mutations. The provided data appear to be in accordance with the known alteration of GSH levels in central nervous system and strengthen the hypothesis of oxidative stress as an important, possibly crucial mechanism in the pathogenesis of AD.

Implication of alpha1-antichymotrypsin polymorphism in familial Alzheimer's disease.

A common polymorphism in the alpha1-antichymotrypsin (ACT) gene has been shown to modify the Apolipoprotein E (ApoE) epsilon4-associated Alzheimer's disease (AD) risk identifying the combination of the ACT/AA and ApoE epsilon4/epsilon4 genotypes as a potential susceptibility marker for AD. Using the polymerase chain reaction, we analyzed the segregation of the ACT and ApoE polymorphisms in familial Alzheimer's disease (FAD) patients carrying mutations in Presenilin (PS) and APP genes and in both early onset (EO) and late onset (LO) FAD patients without known mutations. Our data suggest that ACT does not represent an additional risk factor for PS and APP mutated families. However, in LOFAD patients a high frequency of the combined ACT/AA and ApoE epsilon4/epsilon4 genotypes suggest that ACT may interact with ApoE and play a role in LOFAD.

No implication of apolipoprotein E polymorphism in Italian schizophrenic patients.

Numerous studies have provided evidence for a genetic association of the Apolipoprotein E (ApoE) epsilon4 allele and late onset familial and sporadic Alzheimer's disease (AD). Clinical observations show that a proportion of schizophrenic patients may suffer from severe cognitive impairment. That could reflect a particular clinical aspect of this mental disorder or a common, yet unknown, neurodegenerative mechanism. We analysed the ApoE gene polymorphism in a sample of 69 Italian patients with schizophrenia, 140 AD patients and 121 controls. In schizophrenic patients, the distribution of ApoE genotypes does not significantly differ from that of controls. No effect of the ApoE genotype on age of onset was found. The frequency of ApoE alleles in Italian schizophrenic patients is comparable with control values, suggesting that ApoE polymorphism does not represent a risk factor for schizophrenia.

Growth properties and growth factor responsiveness in skin fibroblasts from centenarians.

Human fibroblast cultures, which have a finite replicative lifespan in vitro, are the most widely used model for the study of senescence at the cellular level. An inverse relationship between replicative capability and donor age has been reported in human fibroblast strains. We studied the growth capacity of fibroblast primary cultures derived from people whose lifespan was as closer as possible to the expected maximum human lifespan, i.e. people over one hundred. Our data suggest that outgrowth of fibroblasts from biopsies, growth kinetics at different population doubling levels, capability to respond to a classical mitogenic stimulus (such as 20% serum) and a variety of growth factors, were remarkably similar in fibroblasts from centenarians and young controls. On the whole, our data challenge the tenet of a simple and strict relationship between in vivo aging and in vitro proliferative capability of human fibroblasts, at least at the individual level.

Presenilin-1 gene intronic polymorphism in sporadic and familial Alzheimer's disease.

A recent observation has shown a genetic association between an intronic polymorphism in the Presenilin-1 (PS-1) gene and late onset Alzheimer's disease (AD). The homozygosity of the 1 allele in the PS-1 gene was associated with a doubling of the risk for late onset AD. However, contrasting results have been published. We analyzed the distribution of the PS-1 intronic polymorphism in patients with sporadic AD and in seven familial AD (FAD) families carrying pathogenetic mutations in the amyloid precursor protein (APP) and Presenilin (PS-1 and PS-2) genes. Significant differences in PS-1 allele frequencies were observed in the Presenilin genes mutated families but not in late onset AD patients and in APP mutated families.

Apolipoprotein E and alpha1-antichymotrypsin polymorphism in Alzheimer's disease.

A recent observation has shown that a common polymorphism in the alpha1-antichymotrypsin (ACT) gene modifies the apolipoprotein E (ApoE) epsilon4-associated Alzheimer's disease (AD) risk identifying the combination of the ACT/AA and ApoE epsilon4/epsilon4 genotypes as a potential susceptibility marker for AD. We analyzed the segregation of the ApoE and ACT polymorphism in sporadic and familial AD patients. In none of the sporadic AD patients did we find the combination of the ACT/AA and ApoE epsilon4/epsilon4 genotypes. The frequency of ApoE epsilon4/epsilon4 homozygosity in the AD sample resulted highest for the ACT/ TT genotype (17.6%). Our data fail to confirm any additional association with AD beyond the ApoE epsilon4 allele with any ACT genotype, suggesting that ACT does not represent an additional risk factor for AD.

c-fos/c-jun expression and AP-1 activation in skin fibroblasts from centenarians.

In vitro replicative senescence is characterized by an irreversible growth arrest due to the inability of the cell to induce some key regulators of cell cycle progression, such as c-fos and AP-1, in response to mitogenic stimuli. In vitro replicative senescence and in vivo aging have been assumed to be two related phenomena, likely controlled by overlapping or interacting genes. As a corollary, fibroblasts from centenarians, which have undergone a long process of senescence in vivo should have very limited proliferative capability. On the contrary, in a previous work we found that fibroblasts from centenarians exhibited the same capacity to respond to different mitogenic stimuli as fibroblasts from young donors. Here we provide evidences that the well preserved proliferative response is likely due to the fact that some pivotal regulators- c-fos, c-jun and AP-1-are still fully inducible, despite a long process of in vivo senescence. Our data therefore suggest that in vivo and in vitro aging are separate phenomena whose possible relationships, if any, have to be ascertained very carefully.

Alteration of acylphosphatase levels in familial Alzheimer's disease fibroblasts with presenilin gene mutations.

Acylphosphatase (AcPase), an enzyme that modulates the activity of Ca(2+)-ATPase by hydrolysing its phosphorylated moiety, has been found to be significantly higher in cultured skin fibroblasts from donors affected by early onset familial Alzheimer's disease (EOFAD) with PS-1 and PS-2 gene mutations. Of the two known isoenzymes of acylphosphatase, only the erythrocyte one accounts for the total increase in activity. No relevant alteration was observed in phosphotyrosine phosphatase activity (PTPase), in Ca(2+)-ATPase and Na+, K(+)-ATPase activities of the same cells as compared to age-matched controls. This finding could suggest a possible explanation for the calcium-dependent biochemical alterations previously described in Alzheimer's disease fibroblasts.

Epistatic effect of APP717 mutation and apolipoprotein E genotype in familial Alzheimer's disease.

We found a new familial Alzheimer's disease kindred in which the disease cosegregates with the APP717Val-->Ile mutation and in which all of the three most common apolipoprotein E (ApoE) alleles are represented. We studied the relationship between ApoE genotype and the clinical expression of the disease and found that in this amyloid precursor protein-mutated family, ApoE genotype influences the age at onset of the disease. Three mutated subjects heterozygous for the epsilon 4 allele had the earliest age at onset in this family, subjects heterozygous for the epsilon 2 allele had the latest age at onset, and subjects homozygous for the epsilon 3 allele had an intermediate age at onset. In this large kindred we also found an amyloid precursor protein-mutated subject 2.4 standard deviations older than the mean age at onset without clinical signs and symptoms of the disease and carrying the epsilon 2/epsilon 3 genotype.

ApoE genotype and familial Alzheimer's disease: a possible influence on age of onset in APP717 Val-->Ile mutated families.

Recent studies have shown a genetic association of the apolipoprotein E (ApoE) epsilon 4 allele with late onset familial and sporadic Alzheimer's disease (AD). In this study we analysed the possible association of the genetic polymorphism of the ApoE gene with age of onset in Italian familial Alzheimer's disease (FAD) families including two early onset familial Alzheimer's (EOFAD) families with the APP717 Val-->Ile mutation in the amyloid precursor protein (APP) gene on chromosome 21. In none of the FAD families analysed was there a significant effect of the ApoE genotype on the age of onset with the exception of one of the two mutated EOFAD families in which the epsilon 2 allele delayed the age of onset.

Alterations in metabolic properties in fibroblasts in Alzheimer disease.

Alzheimer disease (AD) leads to alterations in several biochemical properties in cultured skin fibroblasts. Because abnormal glucose metabolism has been reported in both in vivo and in vitro studies of the brain, we examined glucose and glutamine oxidation and lactate production in cultured skin fibroblasts from nine patients with familial AD, 19 with sporadic AD, and 20 age-matched controls. The production of CO2 from glucose and glutamine was significantly lower in both groups of Alzheimer fibroblasts compared to controls after 10 min or 1, 2, and 4 h of incubation. The reduction in CO2 production was most evident after 1 h of incubation with either (U-14C)-glucose or (U-14C)-glutamine. Lactate concentration was comparable in all groups at any time of incubation. These findings suggest that processes that require mitochondrial function as glucose or glutamine oxidation are altered in AD and provide evidence that complex metabolic differences are expressed in cultured nonneuronal cells from Alzheimer patients.

ApoE allele frequencies in Italian sporadic and familial Alzheimer's disease.

Recent studies have provided evidence of association of apolipoprotein E (ApoE) epsilon 4 allele and late onset familial and sporadic Alzheimer's disease (AD). Epidemiological studies have established allelic variation at the ApoE locus. We have analyzed the ApoE gene polymorphism in a sample of 446 Italian subjects. Our data confirm a significant association between epsilon 4 allele and sporadic AD. The frequency of epsilon 4 allele in early onset familial AD patients was comparable to control values suggesting that epsilon 4 allele does not represent a risk factor for early onset familial AD (EOFAD). Moreover, we found a not previously reported association between ApoE epsilon 2 allele and sporadic AD and EOFAD.