👤 Orane Visvikis

Transcription factor EB (TFEB) is a key transcription factor that orchestrates the cellular response to stress. Dysregulation of TFEB is associated with a range of human diseases, and understanding the regulatory mechanisms of TFEB is crucial for identifying potential drug targets. In this study, we used Show less

To investigate the association of 21 polymorphisms within 13 genes, APOE, APOB, APOC3, CETP, LPL, PON1, MTHFR, FGB, F5, GPIIIa, SELE, ACE and AGT, with inter-individual blood pressure (BP) variation. Seven hundred and seventy-six men and 836 women, free of antihypertensive and lipid-lowering medications, were selected from the Stanislas Cohort. ANOVA on blood pressure values after adjustment for covariates [age, body mass index (BMI), contraceptive pill, tobacco and alcohol] showed that lipoprotein lipase (LPL) Ser447Ter and glycoprotein IIIA (GpIIIa) Pl polymorphisms were significantly associated with BP in women (0.01 < or = P < or = 0.05), whereas BP levels in men were significantly different according to apolipoprotein CIII (APOC3) 3206T/G and -482C/T polymorphisms (P < or = 0.05). In women, compared to the most common allele, the GpIIIa Pl allele was associated with increased mean arterial pressure (MAP) (P < 0.05) and pulse pressure (PP) (P < 0.001), and the LPL 447Ter allele was associated with decreased systolic blood pressure (SBP) and PP levels (0.001 < or = P < or = 0.05). These two polymorphisms appeared to act independently. In men, the APOC3 3206GG genotype was related to decreased diastolic blood pressure (DBP) and MAP levels (P < or = 0.01), and the APOC3 -482T allele with decreased PP levels (P < or = 0.05). The presence of both the -482C allele and the 3206GG genotype was related to decreased DBP, suggesting that specific haplotypes might be involved. The APOC3, LPL and GpIIIa genes were found to be associated with BP levels. The contributions of these genes, although modest, are consistent with the polygenic nature of BP levels. Show less

Apolipoprotein C-III (apoC-III) is involved in triglycerides metabolism, and is therefore important for the pathogenesis of coronary heart diseases. However, to our knowledge serum apoC-III variation factors and reference limits have never been determined, so the aim of this study was to establish them and facilitate clinical usefulness. We measured serum apoC-III concentration of apparently healthy subjects of the Stanislas Cohort by an immunoturbidimetric method. Genetic polymorphisms within the APOC3, APOE, APOAIV, and LPL genes were determined by a multiplex PCR. Serum apoC-III concentration varied from 28.2 mg/l to 225.8 mg/l in the overall sample and between subjects variability was about 30%. Factors influencing apoC-III concentration were age, BMI in adult men, alcohol consumption in adults, oral contraceptive intake in women, the post-pubescent status in boys. The APOC3 1100T allele in adult men and the APOC3 -455C allele in boys were associated with increased apoC-III concentration. The APOA4 360His allele was associated with decreased apoC-III concentration in women. We also established reference limits of serum apoC-III concentration according to age and gender. Show less

The contribution of 17 polymorphisms within 13 candidate genes on lipid trait variability was investigated by a multiplex assay in 772 men and 780 women coming for a health checkup examination. The studied genes were APOE, APOB, APOC3, CETP, LPL, PON, MTHFR, FGB, GpIIIa, SELE, ACE, and AGT. We found that APOB-Thr71Ile, APOE-(112/158), APOC3-1100C/T, and SELE-98G/T polymorphisms had a significant effect on lipid traits (P < or = 0.001 to P < or = 0.01). Genetic effects accounted for 3.5-5.7% of variation in apolipoprotein B (apoB)-related traits among men, and for 5.7-9.0% among women. The contribution of APOE polymorphism on apoB-related traits variability was two to three times more important in women than in men. We found suggestive evidence for interactive effects between genetics and age, smoking status, and oral contraceptives. Increase of LDL-cholesterol and apoB concentrations with age was stronger among the epsilon4 carriers in women, and apolipoprotein A-I (apoA-I) concentration decreased with age in epsilon4 male carriers. The effect of epsilon2 allele on LDL-cholesterol was more important in the oral contraceptive users. In nonsmokers only, the APOC3-1100C allele in women was related to lower apoB-related traits concentrations, and in men to higher apoA-I and HDL-cholesterol concentrations. In conclusion, this work, in addition to the reinforcement of the already known associations between APOB, APOE, and APOC3 genes and lipids, leads to new perspectives in the complex relationships among genes and environmental factors. The newly observed relationships between E-selectine gene and lipid concentrations support the hypotheses of multiple metabolic pathways contributing to the complexity of lipids variability. Show less

The purpose of this study was to examine the relationship between carotid intima-media thickness (CIMT) interindividual variability and 16 polymorphisms of 11 genes associated with cardiovascular risk factors (genes among lipid and homocysteine metabolisms, blood viscosity, platelet aggregation, leukocyte adhesion and renin-angiotensin system). CIMT was measured by high resolution B mode ultrasonography in an healthy population of 77 men and 84 women, aged 35-54 years and selected from a French cohort: the Stanislas cohort. The polymorphisms studied were genotyped by a multilocus approach. Statistical analysis were done by ANOVA after adjustment of CIMT for age, BMI and smoking and by multiple regression analyses. No association was found with APOB Thr71 Ile, APOC3 -482C/T, -455T/C, GpIIIa P1A, AT1R 1166A/C, AGT Met235Thr, CBS Ile278Thr, SELE 98G/T and SELE Ser128Arg, polymorphism neither in men nor in women. Although, in women we found always no association for the APOC3 3206T/G, 3175C/G, 1100C/T, the CETP Ile405Val, the MTHFR 677C/T and the fibrinogen -455G/A polymorphism's, in men these polymorphism's were associated with CIMT variability (0.01 < or = p < or = 0.05). The most interesting finding was that altogether these genes in men were able to explain a considerable part, 20.6%, of CIMT variability. Therefore, our study gives a new opportunity to understand CIMT variability. Show less

The purpose of this study was to examine the relationship between carotid intima-media thickness (CIMT) inter-individual variability and 16 polymorphisms of 11 genes associated with cardiovascular risk factors (genes among lipid and homocysteine metabolisms, blood viscosity, platelet aggregation, leukocyte adhesion and renin-angiotensin system). CIMT was measured by high resolution B-mode ultrasonography in an healthy population of 77 men and 84 women, aged 35-54 years and selected from a French Cohort: the Stanislas Cohort. The polymorphisms studied were genotyped by a multilocus approach. Statistical analyses were carried out by ANOVA, after adjustment of CIMT for age, body mass index, and smoking, and by multiple regression analyses. No association was found with APOB Thr71Ile, APOC3 -482C/T, -455T/C, GpIIIa P1A, AT1R 1166A/C, AGT Met235Thr, CBS Ile278Thr, SELE 98G/T, and SELE Ser128Arg, polymorphisms neither in men nor in women. Although, in women we did not find any association for APOC3 3206T/G, 3175C/G, 1100C/T, CETP Ile405Val, MTHFR 677C/T and fibrinogen -455G/A polymorphisms; in men these polymorphisms were associated with CIMT variability (p< or =0.01; p< or =0.05). The most interesting finding was that altogether these genes in men were able to explain a considerable part, 20.6%, of CIMT variability. Therefore, our study gives a new opportunity to understand CIMT variability. Show less

A multilocus assay was used to genotype up to 27 variable sites in 15 genes in French and Italian, presumed to be healthy populations (n=1480, n=162, respectively). These genes are involved in lipid metabolism (APOE, APOB, APOC3, CETP, LPL, PON), homocysteine metabolism (CBS, MTHFR), blood viscosity (Fibrinogen, FV), platelet aggregation (GpIIIa), leukocyte adhesion (SELE), and renin-angiotensin system (AT1R, ACE, AGT). Allele frequencies for all the markers were compared between the two populations. Five allele frequencies differed between the two European countries: APOB 71Ile (p < 0.001), SELE 98T (p < 0.001), SELE 128Arg (p < or = 0.01), APOE E4 (p < or = 0.01) and MTHFR 677T (p < or = 0.01), suggesting the existence of a north-south gradient in European allele frequencies. The other allele frequencies : APOC3 -482T, -455C, 1100T, 3175G, 3206G; LPL -93G, 9Asn, 291Ser; CETP 405Val; PON 192Arg; ACE Del; AGT 235Thr; AT1R 1166C; CBS 278Thr, GpIIIa P1A2; Fibrinogen -455A, FV 506Gln and SELE 554Phe, were similar between the two populations. They were also similar to those observed in other European countries. Show less

Until now, our familial studies have showed that shared genetic and environmental factors are involved on lipid parameters variability. More precisely, being working on 119 families we have showed that: a) The apolipoprotein E (apo E) common polymorphism is involved in the total cholesterol, low density lipoprotein cholesterol (LDL-Chol), apo E, apo B levels variability, b) the apolipoprotein A-IV gene had no effect on lipid metabolism parameters variability, apo A-IV levels included, c) the apolipoprotein B gene was associated with total cholesterol, high density lipoprotein cholesterol, LDL-Chol, triglycerides and apo B levels genetic variability, d) the lipoproteine lipase (LPL) gene was responsible for 6.5% of the triglycerides variability, e) the apo E and LPL 447 polymorphisms influence in conjunction lipid parameters. These preliminary results on effects and combination effects of polymorphic genes show the interest of a multilocus approach. We have used in a subgroup of 416 individuals of a familial cohort (Stanislas Cohort) a prototype assay that genotypes a panel of 35 polymorphic sites on 15 candidate genes of Cardiovascular diseases. Each sample is amplified by two multiplex polymerase chain reactions, then hybridized to an array of immobilized, oligonucleotide probes. The frequencies of the rare alleles were in agreement with those reported by others in caucasian populations. The realisation of this multiplex assay in the 1,006 families of the Stanislas Cohort, which is underway, will allow us a better understanding of the inter-individual variability of lipids and will contribute to the determination of the genetic susceptibility of one's individual to cardiovascular risk. Show less