[Show abstract][Hide abstract] ABSTRACT: Aims: To determine whether placental IGF1R, IGFBP3, INSR and IGF1 DNA methylation and mRNA levels were dysregulated when exposed to maternal impaired glucose tolerance (IGT) and investigate whether the epigenetic profile is associated with feto-placental developmental markers. Patients & methods: The IGT diagnosis was made according to the WHO criteria (IGT: n = 34; normal glucose tolerance [NGT]: n = 106). DNA methylation and mRNA levels were quantified using bisulfite pyrosequencing and qRT-PCR, respectively. Results: IGF1R and IGFBP3 DNA methylation levels were lower in placentas exposed to IGT compared with NGT (-4.3%; p = 0.021 and -2.5%; p = 0.006 respectively) and correlated with 2-h post-oral glucose tolerance test (OGTT) glycemia (r = -0.23; p = 0.010 and r = -0.20; p = 0.028, respectively). IGF1R mRNA levels were associated with newborns' growth markers (e.g., birth weight; r = 0.20; p = 0.032). Conclusion: These results support the growth-promoting role of the IGF system in placental/fetal development and suggest that the IGF1R and IGFBP3 DNA methylation profiles are dysregulated in IGT, potentially affecting the fetal metabolic programming.
[Show abstract][Hide abstract] ABSTRACT: Gene polymorphisms associated so far with plasma lipid concentrations explain only a fraction of their heritability, which can reach up to 60%. Recent studies suggest that epigenetic modifications (DNA methylation) could contribute to explain part of this missing heritability. We therefore assessed whether the DNA methylation of key lipoprotein metabolism genes is associated with high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglyceride levels in patients with familial hypercholesterolemia (FH). Untreated FH patients (61 men and 37 women) were recruited for the measurement of blood DNA methylation levels at the ABCG1, LIPC, PLTP and SCARB1 gene loci using bisulfite pyrosequencing. ABCG1, LIPC and PLTP DNA methylation was significantly associated with HDL-C, LDL-C and triglyceride levels in a sex-specific manner (all P<0.05). FH subjects with previous history of coronary artery disease (CAD) had higher LIPC DNA methylation levels compared with FH subjects without CAD (P = 0.02). Sex-specific multivariable linear regression models showed that new and previously reported epipolymorphisms (ABCG1-CpGC3, LIPC-CpGA2, mean PLTP-CpGC, LPL-CpGA3, CETP-CpGA2, and CETP-CpGB2) significantly contribute to variations in plasma lipid levels (all P<0.001 in men and P<0.02 in women), independently of traditional predictors such as age, waist circumference, blood pressure, fasting plasma lipids and glucose levels. These results suggest that epigenetic perturbations of key lipoprotein metabolism genes are associated with plasma lipid levels, contribute to the interindividual variability and might partially explain the missing heritability of plasma lipid levels, at least in FH.
Epigenetics: official journal of the DNA Methylation Society 02/2014; 9(5). · 4.58 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Aim:ADRB3 DNA hypermethylation was recently associated with dyslipidemia in familial hypercholesterolemia (FH). In this study, we verified whether ADRB3 DNA methylation in blood and visceral adipose tissue (VAT) was associated with obesity and its related complications. Methods: DNA methylation levels were measured in the blood of 61 FH men, and the blood and VAT of 30 severely obese men. Common ADRB3 polymorphisms were genotyped in all subjects. Results: Higher ADRB3 DNA methylation levels were significantly associated with lower low-density lipoprotein cholesterol levels (r = -0.40; p = 0.01) in FH, and with a lower waist-to-hip ratio (r = -0.55; p = 0.01) and higher blood pressure (r = 0.43; p = 0.05) in severely obese men. ADRB3 g.-843C>T and p.W64R polymorphisms were found to be strongly associated (p < 0.001) with ADRB3 DNA methylation and mRNA levels. Conclusion: Although further studies are needed, these results suggest that epigenetic changes at the ADRB3 gene locus might be involved in the development of obesity and its related metabolic complications.
[Show abstract][Hide abstract] ABSTRACT: Background: There are important inter-individual variations in the incidence and severity of acute pancreatitis in patients with severe hypertriglyceridemia. Several genes involved in triglyceride-rich lipoprotein metabolism or serine proteases pathways are known to influence the risk of pancreatitis. Aim: To evaluate the association between genes regulating serine proteases, chymotrypsin C (CTRC) and serine peptidase inhibitor kazal type1 (SPINK1), and recurrence of hospitalizations for acute pancreatitis or severe abdominal pain in patients with Lipoprotein Lipase Deficiency (LPLD), a rare and extreme monogenic model of severe hypertriglyceridemia and pancreatitis. Method: The CTRC and SPINK1 genes promoter and coding regions sequencing has been performed in a sample of 38 LPLD adults (22 men and 16 women) and 100 controls (53 men and 47 women). Estimation of the association of CTRC and SPINK1 gene variants or combinations of variants with history of hospitalizations for pancreatitis or acute abdominal pain in LPLD was investigated using non-parametric analyses with correction for multiple testing and logistic regression models controlling for age, gender, family history, and life habits. Results: Gene sequencing followed by genotype-stratified analyses of the CTRC and SPINK1 genes in LPLD and controls revealed a positive association between recurrence of hospitalizations and the rs545634 (CTRC)-rs11319 (SPINK1) combination [OR = 41.4 (CI: 2.0-848.0); p = 0.016]. In all models, a positive family history of pancreatitis was a significant predictor of recurrent hospitalizations independently of the contribution of SPINK1 or CTRC (p < 0.001). Conclusion: These results suggest that a positive family history of pancreatitis and genetic markers in the serine protease pathways could be associated with a risk of recurrent hospitalization for acute pancreatitis in severe hypertriglyceridemia due to LPLD.
[Show abstract][Hide abstract] ABSTRACT: Personalized medicine uses various individual characteristics to guide medical decisions. Apolipoprotein (ApoE), the most studied polymorphism in humans, has been associated with several diseases. The purpose of this review is to elucidate the potential role of ApoE polymorphisms in personalized medicine, with a specific focus on neurodegenerative diseases, by giving an overview of its influence on disease risk assessment, diagnosis, prognosis, and therapy. This review is not a systematic inventory of the literature, but rather a summary and discussion of novel, influential and promising works in the field of ApoE research that could be valuable for personalized medicine. Empirical evidence suggests that ApoE genotype informs pre-symptomatic risk for a wide variety of diseases, is valuable for the diagnosis of type III dysbetalipoproteinemia, increases risk of dementia in neurodegenerative diseases, and is associated with a poor prognosis following acute brain damage. ApoE status appears to influence the efficacy of certain drugs, outcome of clinical trials, and might also give insight into disease prevention. Assessing ApoE genotype might therefore help to guide medical decisions in clinical practice.
Frontiers in Aging Neuroscience 01/2014; 6:154. · 5.20 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Lipoprotein(a) [Lp(a)] is an independent risk factor for cardiovascular disease, with limited treatment options. This analysis evaluated the effect of a monoclonal antibody to proprotein convertase subtilisin/kexin 9 (PCSK9), alirocumab 150 mg every 2 weeks (Q2W), on Lp(a) levels in pooled data from 3 double-blind, randomized, placebo-controlled phase 2 studies of 8 or 12 weeks duration conducted in patients with hypercholesterolemia on background lipid-lowering therapy (NCT01266876, NCT01288469, NCT01288443). Data were available for 102/108 patients who received alirocumab 150 mg Q2W and 74/77 patients who received placebo. Alirocumab resulted in a significant reduction in Lp(a) from baseline compared with placebo (–30.3% versus –0.3%, p <0.0001). Median percentage Lp(a) reductions in the alirocumab group were of a similar magnitude across a range of baseline Lp(a) levels, resulting in greater absolute reductions in Lp(a) in patients with higher baseline levels. Regression analysis indicated that less than 5% of the variance in the reduction of Lp(a) was explained by the effect of alirocumab on low-density lipoprotein cholesterol (LDL-C). In conclusion, pooled data from 3 phase 2 trials demonstrate substantive reduction in Lp(a) with alirocumab 150 mg Q2W, including patients with baseline Lp(a) >50 mg/dl. Reductions in Lp(a) only weakly correlated with the magnitude of LDL-C lowering.
[Show abstract][Hide abstract] ABSTRACT: Placental lipoprotein lipase (LPL) is crucial for placental lipid transfer. Impaired LPL gene expression and activity were reported in pregnancies complicated by gestational diabetes mellitus (GDM) and intra-uterine growth restriction. We hypothesized that placental LPL DNA methylation is altered by maternal metabolic status and could contribute to fetal programming. The objective of this study was thus to assess whether placental LPL DNA methylation is associated with GDM and both maternal and newborn lipid profiles. Placenta biopsies were sampled at delivery from 126 women including 27 women with GDM diagnosed following a post 75 g-oral glucose tolerance test (OGTT) between weeks 24 and 28 of gestation. Placental LPL DNA methylation and expression levels were determined using bisulfite pyrosequencing and quantitative real-time PCR, respectively. DNA methylation levels within LPL proximal promoter region (CpG1) and intron 1 CpG island (CpGs 2 and 3) were lower in placenta of women with GDM. DNA methylation levels at LPL-CpG1 and CpG3 were also negatively correlated with maternal glucose (2-h post OGTT; r=–0.22; P=0.02) and HDL-cholesterol levels (third trimester of pregnancy; r=–0.20; p=0.03), respectively. Moreover, we report correlation between LPL-CpG2 DNA methylation and cord blood lipid profile. DNA methylation levels within intron 1 CpG island explained up to 26% (r⩽–0.51; P<0.001) of placental LPL mRNA expression variance. Overall, we showed that maternal metabolic profile is associated with placental LPL DNA methylation dysregulation. Our results suggest that site-specific LPL epipolymorphisms in the placenta are possibly functional and could potentially be involved in determining the future metabolic health of the newborn.
[Show abstract][Hide abstract] ABSTRACT: Cellular immune responses to adeno-associated viral (AAV) vectors used for gene therapy have been linked to attenuated transgene expression and loss of efficacy. The impact of such cellular immune responses on the clinical efficacy of alipogene tiparvovec (Glybera®, AAV1-LPLS447X, uniQure, Amsterdam, the Netherlands), a gene-therapy consisting of intramuscular administration of a recombinant (r)AAV1 mediating muscle-directed expression of lipoprotein lipase (LPL), was investigated. Five subjects with LPL-deficiency (LPLD) were administered intramuscularly with a dose of 1 x 1012 gc/kg alipogene tiparvovec. All subjects were treated with immune suppression starting shortly before administration of alipogene tiparvovec and maintained until 12 weeks after administration. Systemic antibody and T cell responses against AAV1 and LPLS447X, as well as local cellular immune responses in the injected muscle were investigated in 5 LPLD subjects. Long term transgene expression was demonstrated despite a transient systemic cellular response and a stable humoral immune response against AAV1 capsid protein. Cellular infiltrates were found in 4 of the 5 subjects but were not associated with adverse clinical events or elevation of inflammation markers. Consistent herewith, CD8-positive T cells in the infiltrates lacked cytotoxic potential. Furthermore, FoxP3-positive/CD4-positive T cells were found in the infiltrates suggesting that multiple mechanisms contribute to local tolerance. Systemic and local immune responses induced by intramuscular injection of alipogene tiparvovec have no impact on safety and did not compromise LPL transgene expression. These findings support the use of alipogene tiparvovec in individuals with LPLD and indicate that muscle directed AAV-based gene therapy remains a promising approach for the treatment of human diseases.
[Show abstract][Hide abstract] ABSTRACT: Genealogical analysis has proven a useful method to understand the origins and frequencies of hereditary diseases in many populations. However, this type of analysis has not yet been used for the investigation of drug intolerance among patients suffering from inherited disorders. This study aims to do so, using data from familial hypercholesterolemia (FH) patients receiving high doses of statins. The objective is to measure and compare various genealogical parameters that could shed light on the origins and heritability of muscular intolerance to statins using FH as a model. Analysis was performed on 224 genealogies from 112 FH subjects carrying either the low-density lipoprotein receptor (LDLR) prom_e1 deletion>15 kb (n=28) or c.259T>G (p.Trp87Gly) (n=84) mutations and 112 non-FH controls. Number of ancestors, geographical origins and genetic contribution of founders, inbreeding and kinship coefficients were calculated using the S-Plus-based GENLIB software package. For both mutations, repeated occurrences of the same ancestors are more frequent among the carriers' genealogies than among the controls', but no difference was observed between tolerant and intolerant subjects. Founders who may have introduced both mutations in the population appear with approximately the same frequencies in all genealogies. Kinship coefficients are higher among carriers, with no difference according to statins tolerance. Inbreeding coefficients are slightly lower among >15-kb deletion carriers than among c.259 T>G carriers, but the differences between tolerants and intolerants are not significant. These findings suggest that although muscular intolerance to statins shows a family aggregation, it is not transmitted through the same Mendelian pattern as LDLR mutations.European Journal of Human Genetics advance online publication, 27 November 2013; doi:10.1038/ejhg.2013.270.
European journal of human genetics: EJHG 11/2013; · 3.56 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background: Homozygous familial hypercholesterolemia (HoFH) is a rare genetic disease characterized by markedly elevated LDL-C and high CVD risk. Lomitapide is approved in the US to lower LDL-C as an adjunct to other lipid lowering agents, including apheresis, for adults with HoFH. We report efficacy and safety findings from a long term extension study in patients treated with lomitapide for 2.5-4.5 years. Methods: Following the pivotal 78 week study, eligible patients entered an open label extension phase and continued lomitapide at their maximum tolerated dose. The primary efficacy endpoint was mean % change in LDL-C from baseline to week 126 (~2.5 years). Safety endpoints included assessment of hepatic fat as measured by nuclear magnetic resonance spectroscopy (NMRS), liver function tests, and adverse events (AEs). Results: Nineteen of 23 patients who completed the pivotal study entered the extension study. Follow-up ranged from ~2.5 - 4.5 years. LDL-C levels were reduced by 45.5% at week 126 (356 ± 127 mg /dL vs. 189 ± 120 mg/dL; P <0.001). Similar mean % reductions were observed for Apo B -54%, non-HDL-C -47%, VLDL-C -37%, and triglycerides -53% (median), (P ≤0.006 for all). At any time on study, an LDL-C of ≤ 100 or ≤ 70 mg/dL was achieved by 13 (68%) and 9 (47%) patients, respectively. Median hepatic fat levels were 6.5% at entry to the extension phase and remained stable over 2 years (median 7.7% (range 0.6, 35.2)). Transient aminotransferase elevations >5x ULN occurred in 4 patients; 1 patient had a reversible ALT elevation of 24x ULN following co-prescription of agomelatine and a potent inhibitor of CYP3A4 (clarithromycin); 1 other patient, who use excessive alcohol, was withdrawn due to persistent ALT elevations >5x ULN. No Hy’s law cases were reported. The AE profile in patients who continued on the extension study was similar to the pivotal trial. GI symptoms were the most common AEs,observed in 63% (12/19) of patients in the extension study. One sudden cardiac death occurred in a 58 year old patient with known CAD. Conclusions: Results of the ongoing extension study are consistent with those observed in the pivotal study and demonstrate sustained efficacy and an acceptable longer-term safety profile of lomitapide in patients with HoFH.
AHA 2013, November 16th-20th, Dallas, TX, Dallas, TX , USA; 11/2013 · 15.20 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: MTP inhibition is expected to cause triglyceride accumulation in hepatocytes. Lomitapide an MTP inhibitor approved in the US for use in HoFH patients may induce hepatic steatosis. We report liver safety data collected for up to 4.5 years in an ongoing study
American Heart Association, Dallas, Texas, USA; 11/2013
[Show abstract][Hide abstract] ABSTRACT: In utero environmental perturbations have been associated with epigenetic changes in the offspring and a lifelong susceptibility to cardiovascular diseases (CVD). DNA methylation at the ATP-binding cassette transporter A1 (ABCA1) gene was previously associated with CVD, but whether these epigenetic marks respond to changes in the maternal environment is unknown. This study was undertaken to assess the associations between the maternal metabolic profile and ABCA1 DNA methylation levels in placenta and cord blood. Placenta and cord blood samples were obtained at delivery from 100 women including 26 with impaired glucose tolerance (IGT) diagnosed following a 75 g-oral glucose tolerance test (OGTT) between week 24 and 28 of gestation. ABCA1 DNA methylation and mRNA levels were measured using bisulfite pyrosequencing and quantitative real-time PCR, respectively. We report that ABCA1 DNA methylation levels on the maternal side of the placenta are correlated with maternal HDL-C levels (r<-0.21; P<0.04) and glucose levels 2h post-OGTT (r = 0.25; P = 0.02). On the fetal side of the placenta, ABCA1 DNA methylation levels are associated with cord blood triglyceride levels (r = -0.28; P = 0.01). ABCA1 DNA methylation variability on both sides of the placenta are also associated with ABCA1 mRNA levels (r<-0.35; P = 0.05). As opposed to placenta, cord blood DNA methylation levels are negatively correlated with maternal glucose 2h post-OGTT (r = -0.26; P = 0.02). In conclusion, the epivariations observed in placenta and cord blood likely contribute to an optimal materno-fetal cholesterol transfer. These in utero epigenetics adaptations may also potentially trigger the long-term susceptibility of the newborn to dyslipidemia and CVD.
Epigenetics: official journal of the DNA Methylation Society 10/2013; 8(12). · 4.58 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background: Homozygous familial hypercholesterolemia (HoFH) is a rare genetic disease characterized by markedly elevated LDL-C and high, premature CVD risk. Lomitapide significantly reduced LDL-C levels in HoFH patients in a pivotal phase 3 study (Lancet 2013; 381:40) and is approved in the US as an adjunct to other lipid lowering agents, including apheresis, for adults with HoFH. We report findings from a long term extension study in patients treated with lomitapide for 2.5-4.5 years.
Methods: Following the pivotal 78 week study, patients were eligible to enter an open label extension study during which they continued lomitapide at their maximum tolerated dose. The primary endpoint was mean % change in LDL-C from baseline of the pivotal study to week 126 (~2.5 years). Secondary endpoints included mean % change in other lipid parameters and long-term safety. The extension study is ongoing and up to 4.5 years of safety data are available.
Results: 23 patients completed the pivotal study and 19 entered the extension. Efficacy data are reported for 17 patients who completed treatment though week 126. LDL-C levels were reduced by 45.5% at week 126 (356 ± 127 mg /dL vs. 189 ± 120 mg/dl; P < 0.001). Similar % reductions were observed for Apo B -54%, triglycerides -38%, non-HDL-C -47%, and VLDL-C -37% (P ≤0.006 for all). At any time on study, an LDL-C of ≤ 100 or ≤ 70 mg/dL was achieved by 13 (68%) and 9 (47%) patients, respectively. Lomitapide was generally well tolerated with an AE profile similar to that observed in the pivotal trial. Gastrointestinal symptoms were the most common AEs (95% overall; 63% for the extension). Five patients had elevations in aminotransferases > 5x ULN. In 1 patient, ALT reached 24×ULN in the setting of concomitant medications known to cause liver injury. One patient was withdrawn due to aminotransferase elevations- persistent ALT elevations >5x ULN in the setting of excessive alcohol intake. No Hy’s law cases were reported. One death occurred and was attributed to pre-existing cardiac disease.
Conclusions: In 17 patients who completed treatment through week 126, the effect of lomitapide on LDL-C and ApoB containing lipoproteins was durable and consistent with pivotal trial results. Results of this extension study support robust and sustained efficacy of lomitapide with an acceptable longer-term safety profile.
European Society of Cardiology, Amsterdam, Netherlands; 08/2013
[Show abstract][Hide abstract] ABSTRACT: Offspring exposed to gestational diabetes mellitus (GDM) have an increased risk for chronic diseases, and one promising mechanism for fetal metabolic programming is epigenetics. Therefore, we postulated that GDM exposure impacts the offspring's methylome and used an epigenomic approach to explore this hypothesis. Placenta and cord blood samples were obtained from 44 newborns, including 30 exposed to GDM. Women were recruited at first trimester of pregnancy and followed until delivery. GDM was assessed after a 75-g oral glucose tolerance test at 24-28 weeks of pregnancy. DNA methylation was measured at > 485,000 CpG sites (Infinium HumanMethylation450 BeadChips). Ingenuity Pathway Analysis was conducted to identify metabolic pathways epigenetically affected by GDM. Our results showed that 3,271 and 3,758 genes in placenta and cord blood, respectively, were potentially differentially methylated between samples exposed or not to GDM (p-values down to 1 × 10 (-06) ; none reached the genome-wide significance levels), with more than 25% (n = 1,029) being common to both tissues. Mean DNA methylation differences between groups were 5.7 ± 3.2% and 3.4 ± 1.9% for placenta and cord blood, respectively. These genes were likely involved in the metabolic diseases pathway (up to 115 genes (11%), p-values for pathways = 1.9 × 10 (-13) < p < 4.0 × 10 (-03) ; including diabetes mellitus p = 4.3 × 10 (-11) ). Among the differentially methylated genes, 326 in placenta and 117 in cord blood were also associated with newborn weight. Our results therefore suggest that GDM has epigenetic effects on genes preferentially involved in the metabolic diseases pathway, with consequences on fetal growth and development, and provide supportive evidence that DNA methylation is involved in fetal metabolic programming.
Epigenetics: official journal of the DNA Methylation Society 07/2013; 8(9). · 4.58 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The clinical application of adeno-associated virus vectors (AAVs) is limited because of concerns about AAV integration-mediated tumorigenicity. We performed integration-site analysis after AAV1-LPL(S447X) intramuscular injection in five lipoprotein lipase-deficient subjects, revealing random nuclear integration and hotspots in mitochondria. We conclude that AAV integration is potentially safe and that vector breakage and integration may occur from each position of the vector genome. Future viral integration-site analyses should include the mitochondrial genome.
[Show abstract][Hide abstract] ABSTRACT: Homozygous familial hypercholesterolemia (HoFH) is a rare genetic disease characterized by markedly elevated LDL-C and high CVD risk. Lomitapide, a microsomal triglyceride transfer protein (MTP) inhibitor, significantly reduces LDL-C levels in HoFH patients (Cuchel et al, Lancet 2013;381:40-46) and is approved in the US as an adjunct to other lipid lowering agents, including apheresis, for adults with HoFH.. In the pivotal phase 3 study lomitapide was associated with side effects that primarily included GI disturbances (in 93% of patients) and elevations in hepatic transaminase levels described in detail in the file attached. We report the management of aminotransferase elevations in the pivotal phase 3 study.
81st Congress of the European Atherosclerosis Society; 06/2013