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Giuseppe Passarino

Publications and source records attributed to Giuseppe Passarino.

15 recordsLinked to original sources

Epigenetic aging and autosomal methylation remodeling in Anderson-Fabry disease.

Anderson-Fabry disease (AFD) is a rare X-linked lysosomal storage disorder characterized by marked clinical heterogeneity and incompletely understood genotype-phenotype correlations. While X-chromosome inactivation has been extensively investigated, the contribution of autosomal epigenetic mechanisms to phenotypic variability remains poorly defined. Here, we performed an exploratory genome-wide DNA methylation analysis in 32 AFD patients (22 females and 10 males; mean age 51.7 years) recruited within a multicenter regional research project in Calabria (Italy). DNA methylation profiling was conducted using the Infinium MethylationEPIC v2.0 array. The analysis integrated two complementary approaches: differential methylation analysis and evaluation of biological aging through multiple epigenetic clocks, including Horvath, Hannum, PhenoAge, Skin & Blood, GrimAge, and DunedinPACE. Exploratory methylome-wide analysis identified a limited set of CpG loci showing nominal evidence of methylation differences between carriers of pathogenic and non-pathogenic variants; however, none remained statistically significant after correction for multiple testing. Annotation of the top-ranking nominal CpG associations highlighted genes involved in biological processes including vascular regulation, intracellular trafficking, cytoskeletal organization, immune signaling, and lipid metabolism. No significant differences between groups were observed for the conventional epigenetic age-acceleration measures examined. In contrast, carriers of pathogenic variants showed significantly higher DunedinPACE values (p = 0.0328), indicating a faster estimated pace of biological aging. This finding suggests that DunedinPACE may capture aspects of the cumulative systemic burden associated with pathogenic GLA variants, although confirmation in larger independent cohorts is required. Overall, this pilot epigenomic study provides preliminary evidence that autosomal epigenetic remodeling and biological aging acceleration may contribute to phenotypic heterogeneity in AFD.

Anderson-Fabry disease↗

Evidence for a relationship between genetic polymorphisms of the L-DOPA transporter LAT2/4F2hc and risk of hypertension in the context of chronic kidney disease.

BACKGROUND: Chronic kidney disease (CKD) and hypertension are chronic diseases affecting a large portion of the population frequently coexistent and interdependent. The inability to produce/use adequate renal dopamine may contribute to the development of hypertension and renal dysfunction. The heterodimeric amino acid transporter LAT2/4F2hc (SLC7A8/SLC3A2 genes) promotes the uptake of L-DOPA, the natural precursor of dopamine. We examined the plausibility that SLC7A8/SLC3A2 gene polymorphisms may contribute to hypertensive CKD by affecting the L-DOPA uptake. METHODS: 421 subjects (203 men and 218 women, mean age of 78.9&#x2009;&#xb1;&#x2009;9.6&#xa0;years) were recruited and divided in four groups according to presence/absence of CKD, defined as reduced estimated glomerular filtration rate (eGFR&#x2009;<&#x2009;60&#xa0;ml/min/m2) calculated using the creatinine-based Berlin Initiative Study-1 (BIS1) equation, and to presence/absence of hypertension (systolic blood pressure&#x2009;&#x2265;&#x2009;140 and/or diastolic blood pressure&#x2009;&#x2265;&#x2009;90&#xa0;mmHg). Subjects were analysed for selected SNPs spanning the SLC7A8 and SLC3A2 loci by Sequenom MassARRAY iPLEX platform. RESULTS: The most significant SNP at the SLC3A2 (4F2hc) locus was rs2282477-T/C, with carriers of the C-allele having a lower chance to develop hypertension among CKD affected individuals [OR&#x2009;=&#x2009;0.33 (CI 0.14-0.82); p&#x2009;=&#x2009;0.016]. A similar association with hypertensive CKD was found for the SLC7A8 (LAT2) rs3783436-T/C, whose C-allele resulted associated with decreased risk of hypertension among subjects affected by CKD [OR&#x2009;=&#x2009;0.56 (95% CI 0.35-0.90; p&#x2009;=&#x2009;0.017]. The two variants were predicted to be potentially functional. CONCLUSIONS: The association between SLC3A2 and SLC7A8 variants to hypertension development in patients with renal failure could be linked to changes in L-DOPA uptake and consequently dopamine synthesis. Although the associations do not survive correction for Bonferroni multiple testing, and additional research is needed, our study opens new avenues for future basic and translational research in the field of hypertensive CKD.

Aged↗

Sex and age specificity of susceptibility genes modulating survival at old age.

OBJECTIVE: We aimed to investigate the influence of the genetic variability of candidate genes on survival at old age in good health. METHODS: First, on the basis of a synthetic survival curve constructed using historic mortality data taken from the Italian population from 1890 onward, we defined three age classes ranging from 18 to 106 years. Second, we assembled a multinomial logistic regression model to evaluate the effect of dichotomous variables (genotypes) on the probability to be assigned to a specific category (age class). Third, we applied the regression model to a cross-sectional dataset (10 genes; 972 subjects selected for healthy status) categorized according to age and sex. RESULTS: We found that genetic factors influence survival at advanced age in good health in a sex- and age-specific way. Furthermore, we found that genetic variability plays a stronger role in males than in females and that, in both genders, its impact is especially important at very old ages. CONCLUSIONS: The analyses presented here underline the age-specific effect of the gene network in modulating survival at advanced age in good health.

Adolescent↗

Mitochondrial DNA involvement in human longevity.

The main message of this review can be summarized as follows: aging and longevity, as complex traits having a significant genetic component, likely depend on a number of nuclear gene variants interacting with mtDNA variability both inherited and somatic. We reviewed the data available in the literature with particular attention to human longevity, and argued that what we hypothesize for aging and longevity could have a more general relevance and be extended to other age-related complex traits such as Alzheimer's and Parkinson's diseases. The genetics which emerges for complex traits, including aging and longevity, is thus even more complicated than previously thought, as epistatic interactions between nuclear gene polymorphisms and mtDNA variability (both somatic and inherited) as well as between mtDNA somatic mutations (tissue specific) and mtDNA inherited variants (haplogroups and sub-haplogroups) must be considered as additional players capable of explaining a part of the aging and longevity phenotype. To test this hypothesis is one of the main challenge in the genetics of aging and longevity in the next future.

Cell Nucleus↗

Handgrip strength among nonagenarians and centenarians in three European regions.

BACKGROUND: Handgrip strength is an important predictor of disability and mortality among old people. The aim was to compare the grip strength among very old people in three regions of Europe. METHODS: In this substudy of the European Challenge for Healthy Aging project, only the long-lived probands were included. The maximum value of three measurements of handgrip strength was selected for the analysis. Adjustment for factors known to be correlated with grip strength was made by linear regression. RESULTS: Among 598 very old people (median age = 98 years) a clear North-South gradient was observed: For men, handgrip strength dropped from 24.2 kg in Southern Denmark to 20.8 kg in Languedoc-Roussillon, France and 14.2 kg in Calabria, Italy (p < .0001), whereas for women the drop was smaller (from 12.2 to 9.2 kg; p = .0021). The difference remains significant after adjustment for age, gender, housing, knee height, Activities of Daily Living (ADL) scale score, score on the Six-Item Mini-Mental State Examination, chair stand, and number of age-related diseases, although these factors explain two thirds of the variation in handgrip strength. CONCLUSIONS: Among nonagenarians and centenarians in three different European regions, we found a significant North-South gradient in handgrip strength with substantially lower values in Calabria. This finding may be due both to population background differences (e.g., genetic variations, birth weight, childhood growth) and to sociocultural differences (e.g., lifestyle, health care).

Aged↗

Gene expression of cytokines and cytokine receptors is modulated by the common variability of the mitochondrial DNA in cybrid cell lines.

Some lines of evidence indicate that common polymorphisms of mitochondrial DNA (mtDNA) act as susceptibility factors in complex traits, such as age-related common diseases. There is also evidence that the cell capability to compensate ravages caused by intrinsic or extrinsic stress factors could contribute to some of these diseases. The cross-talk between nuclear and mitochondrial genome may link the above observations if we assume that the transcription of stress-responder nuclear genes is modulated according to the mtDNA common variability. Cytokines and cytokine receptors are key molecules in stress response. We could, therefore, check the above hypothesis by analyzing expression patterns of cytokine and cytokine receptor genes in response to stress in cell lines sharing the same nuclear genome but different mtDNA. By using a cybrid model (143B.TK- osteosarcoma cells depleted of their own mtDNA and repopulated with foreign mitochondria) we show that the transcription patterns of some of such genes are specifically modulated by the variability of the mitochondrial genome not only under stress conditions (interleukin-6) but also at basal conditions (interleukin-1beta and tumor necrosis factor receptor 2). These findings provide a first experimental evidence of a relationship between mtDNA common variability and expression pattern of stress responder nuclear genes in human cells.

Cell Fusion↗

The role of selection in the evolution of human mitochondrial genomes.

High mutation rate in mammalian mitochondrial DNA generates a highly divergent pool of alleles even within species that have dispersed and expanded in size recently. Phylogenetic analysis of 277 human mitochondrial genomes revealed a significant (P < 0.01) excess of rRNA and nonsynonymous base substitutions among hotspots of recurrent mutation. Most hotspots involved transitions from guanine to adenine that, with thymine-to-cytosine transitions, illustrate the asymmetric bias in codon usage at synonymous sites on the heavy-strand DNA. The mitochondrion-encoded tRNAThr varied significantly more than any other tRNA gene. Threonine and valine codons were involved in 259 of the 414 amino acid replacements observed. The ratio of nonsynonymous changes from and to threonine and valine differed significantly (P = 0.003) between populations with neutral (22/58) and populations with significantly negative Tajima's D values (70/76), independent of their geographic location. In contrast to a recent suggestion that the excess of nonsilent mutations is characteristic of Arctic populations, implying their role in cold adaptation, we demonstrate that the surplus of nonsynonymous mutations is a general feature of the young branches of the phylogenetic tree, affecting also those that are found only in Africa. We introduce a new calibration method of the mutation rate of synonymous transitions to estimate the coalescent times of mtDNA haplogroups.

Amino Acid Substitution↗

A novel VNTR enhancer within the SIRT3 gene, a human homologue of SIR2, is associated with survival at oldest ages.

SIR2 genes control life span in model organisms, playing a central role in evolutionarily conserved pathways of aging and longevity. We wanted to verify whether similar effects may act in humans too. First, we searched for variability in the human sirtuin 3 gene (SIRT3) and discovered a VNTR polymorphism (72-bp repeat core) in intron 5. The alleles differed both for the number of repeats and for presence/absence of potential regulatory sites. Second, by transient transfection experiments, we demonstrated that the VNTR region has an allele-specific enhancer activity. Third, by analyzing allele frequencies as a function of age in a sample of 945 individuals (20-106 years), we found that the allele completely lacking enhancer activity is virtually absent in males older than 90 years. Thus the underexpression of a human sirtuin gene seems to be detrimental for longevity as it occurs in model organisms.

Adult↗

Heat shock response by EBV-immortalized B-lymphocytes from centenarians and control subjects: a model to study the relevance of stress response in longevity.

'Successful aging', i.e. the ability to attain old age in relatively good health, is believed to be related to the capability to cope with different environmental stresses. Independently of their specific differentiation, all body cells respond to hyperthermia and other stresses with the production of Heat Shock Proteins (HSPs) that play an important role in cell survival. We investigated the heat shock response in B-lymphoid cell lines from 44 centenarians and 23 younger subjects, by studying both HSP70 synthesis and cell survival after hyperthermic treatment. Interestingly, no significant difference could be found between the two age groups as far as HSP70 synthesis was concerned; moreover, cell lines from centenarians appeared to be less prone to heat-induced apoptosis than lines from younger controls. These results, which are in contrast with previous findings showing an age-related decrease of the HSP70 synthesis and of hyperthermic response, corroborate the above mentioned hypothesis that the biological success of centenarians is due to the preservation of the capability to cope with stresses. An A/C polymorphism identified in the promoter region of HSP70-1 gene had been previously shown to affect the probability to attain longevity in females. To investigate if this effect was related to any influence of this polymorphism on HSP70 protein synthesis the correlation between A/C polymorphism and protein synthesis was investigated. We found that cells from AA centenarian females displayed a lower synthesis of HSP70.

Adult↗

Association of the mitochondrial DNA haplogroup J with longevity is population specific.

Evidences are accumulating on the effects of the variability of mitochondrial DNA (mtDNA) on many complex traits. In particular, mtDNA haplogroup J has been reported to increase the individual chance to attain longevity in northern Italians, Northern Irish and Finns. However, since the genetic contribution to longevity may be population specific, we wanted to verify if haplogroup J does affect longevity also in a southern European population having a different genetic and environmental history. We analysed a population sample (883 subjects, 371 males and 521 females; age range 18-108 years) from southern Italy for the presence of haplogroup J. No frequency increase of this mtDNA haplogroup was found in the older cohorts, suggesting that, in this population, haplogroup J does not play a significant role in longevity. This finding shows that, as for other genetic factors, the association of mtDNA inherited variability with longevity is population specific.

Adolescent↗

Strikingly higher frequency in centenarians and twins of mtDNA mutation causing remodeling of replication origin in leukocytes.

The presence of a genetic component in longevity is well known. Here, the association of a mtDNA mutation with a prolonged life span in humans was investigated. Large-scale screening of the mtDNA main control region in leukocytes from subjects of an Italian population revealed a homoplasmic C150T transition near an origin of heavy mtDNA-strand synthesis in approximately 17% of 52 subjects 99-106 years old, but, in contrast, in only 3.4% of 117 younger individuals (P = 0.0035). Evidence was obtained for the contribution of somatic events, under probable nuclear genetic control, to the striking selective accumulation of the mutation in centenarians. In another study, among leukocyte mtDNA samples from 20 monozygotic and 18 dizygotic twins, 60-75 years old, 30% (P = 0.0007) and 22% (P = 0.011), respectively, of the individuals involved exhibited the homoplasmic C150T mutation. In a different system, i.e., in five human fibroblast longitudinal studies, convincing evidence for the aging-related somatic expansion of the C150T mutation, up to homoplasmy, was obtained. Most significantly, 5' end analysis of nascent heavy mtDNA strands consistently revealed a new replication origin at position 149, substituting for that at 151, only in C150T mutation-carrying samples of fibroblasts or immortalized lymphocytes. Considering the aging-related health risks that the centenarians have survived and the developmental risks of twin gestations, it is proposed that selection for a remodeled replication origin, inherited or somatically acquired, provides a survival advantage and underlies the observed high incidence of the C150T mutation in centenarians and twins.

Adolescent↗

Molecular variation of human HSP90alpha and HSP90beta genes in Caucasians.

Understanding DNA variation within the human genome is fundamental to the identification and interpretation of genetic components underlying complex traits and diseases. Despite their role in many crucial cellular pathways and their reported involvement in many complex diseases no data are available on the molecular variability of the genes coding for Heat Shock Proteins 90Kda (HSP90). Towards this purpose we have used DHPLC methodology to survey, a sample of Caucasians for genetic polymorphisms in the exons and exon-flanking regions of the expressed genes of human HSP90 gene families, HSP90alpha (HSPCAL4, 14q31.3) and HSP90beta (HSPCB, 6p12). A total of 18 and 11 variants were found in the HSP90-alpha and -beta genes respectively, providing an initial view of human genetic variation in these important genes. Only three of the observed mutations altered the genic product. Interestingly, one of the variations observed was a missense mutation leading to the impairment of the hsp90alpha protein.

DNA↗

Different genetic components in the Norwegian population revealed by the analysis of mtDNA and Y chromosome polymorphisms.

The genetic composition of the Norwegian population was investigated by analysing polymorphisms associated with both the mitochondrial DNA (mtDNA) and Y chromosome loci in a sample of 74 Norwegian males. The combination of their uniparental mode of inheritance and the absence of recombination make these haplotypic stretches of DNA the tools of choice in evaluating the different components of a population's gene pool. The sequencing of the Dloop and two diagnostic RFLPs (AluI 7025 and HinfI at 12 308) allowed us to classify the mtDNA molecules in 10 previously described groups. As for the Y chromosome the combination of binary markers and microsatellites allowed us to compare our results to those obtained elsewhere in Europe. Both mtDNA and Y chromosome polymorphisms showed a noticeable genetic affinity between Norwegians and central Europeans, especially Germans. When the phylogeographic analysis of the Y chromosome haplotypes was attempted some interesting clues on the peopling of Norway emerged. Although Y chromosome binary and microsatellite data indicate that 80% of the haplotypes are closely related to Central and western Europeans, the remainder share a unique binary marker (M17) common in eastern Europeans with informative microsatellite haplotypes suggesting a different demographic history. Other minor genetic influences on the Norwegian population from Uralic speakers and Mediterranean populations were also highlighted.

Chromosome Mapping↗

Genetic polymorphism of the major regulatory element HS-40 upstream of the human alpha-globin gene cluster.

The highly conserved 350-bp major regulatory element HS-40 (or alphaMRE) upstream of the human alpha-globin gene cluster is involved in the regulation of alpha-globin gene expression. The study of alphaMRE differences between human populations and the evolution of alphaMRE sequences in mammals may lead to a better understanding of the function and importance of this element in the regulation of expression of the downstream alpha-cluster. Denaturing gradient gel electrophoresis was used to determine the sequence heterogeneity of the alphaMRE region in 276 unrelated individuals, representing seven different populations. Furthermore, we analysed the alpha major regulatory elements of chimpanzee, orang-utan and rhesus monkeys and compared them with the equivalent human and murine sequences. Six different alphaMRE haplotypes (labelled A to F) were found in humans. Haplotype frequencies between the seven populations showed a gradual shift to a higher haplotype A distribution from west to east, being the highest in Indonesians. The African sample shows the largest divergence in haplotypes. Five out of six different haplotypes were present, three of which were exclusively found in Africans. The high prevalence of the haplotype A in humans, together with the conservation of this haplotype in apes, suggests that it is the ancestral one. The alphaMRE fragment appears to be a highly polymorphic marker, which could be used in combination with the regular markers in the alpha-cluster to extend the haplotype and to follow segregation of alpha-thalassaemia genes in population studies more accurately.

Animals↗