👤 A Kretowski

The melanocortin-4 receptor (MC4R) gene harbours one of the strongest susceptibility loci for obesity and obesity-related metabolic consequences. We analysed whether dietary factors may attenuate the associations between Show less

The interactions between lifestyle and genetic factors play an important role in obesity development. Mutations in melanocortin-4-receptor (MC4R) gene are one of the most common cause of monogenic obesity, however, the functional effects of polymorphic variants near MC4R gene in general populations remain uncertain. The aim of our study was to analyze whether the common single nucleotide polymorphisms (SNPs) of MC4R gene influence the food preferences, physical activity, body fat content and distribution, as well as fasting and postprandial energy expenditure and substrates utilization. We genotyped previously identified MC4R SNPs: rs17782313, rs633265, rs1350341, rs12970134 in 927 subjects, who underwent anthropometric, total body fat content, visceral (VAT) and subcutaneous adipose tissue (SAT) measurements, and daily physical activity and dietary intake analysis. In randomly selected 47 subjects the energy expenditure, carbohydrate and lipid utilizations were evaluated in fasting state and after high-carbohydrate and control meals intake. We found the significant associations between studied SNPs of MC4R gene and VAT and VAT/SAT ratio. Moreover, the GG genotype carriers of rs1350341, who had the lowest VAT accumulation (p = 0.012), presented higher relative increase in postprandial carbohydrate utilization (p = 0.013, p = 0.024). We have observed that common SNPs of the MC4R gene influence the body fat content and distribution, as well as relative increase in postprandial carbohydrate utilization. We believe that our study may help to understand better the impact of MC4R gene on obesity development, and to help to provide personalized prevention/treatment strategies to fight against obesity and its metabolic consequences. Show less

Individuals with type 1 diabetes have an increased incidence of coronary artery disease (CAD) and a higher risk of cardiovascular death compared with individuals of the same age in the general population. While chronic hyperglycaemia and insulin resistance partially explain excess CAD, little is known about the potential genetic determinants of accelerated coronary atherosclerosis in type 1 diabetes. The aim of the present study was to evaluate the association of apolipoprotein A-IV (APOA4) polymorphisms with coronary artery calcification (CAC) progression, a marker of subclinical atherosclerosis. Two previously well-studied functional APOA4 polymorphisms resulting in the substitution of the amino acid Thr for Ser at codon 347 and Gln for His at codon 360 were genotyped in 634 subjects with type 1 diabetes and 739 non-diabetic control subjects, the participants of the prospective Coronary Artery Calcification in Type 1 Diabetes (CACTI) study. The His360 allele was associated with a significantly higher risk of CAC progression among patients with type 1 diabetes (33.7 vs 21.2%, p=0.014), but not in the control subjects (14.1 vs 11.1%, p=0.42). Logistic regression analysis confirmed that the presence of the APOA4 His360 allele predicts an increased risk of progression of coronary atherosclerosis in adults with type 1 diabetes of long duration (odds ratio = 3.3, p=0.003 after adjustment for covariates associated with CAD risk). CONCLUSIONS /INTERPRETATION: This is the first report suggesting an association between the APOA4 Gln360His polymorphism and risk of CAC progression in subjects with type 1 diabetes. Additional studies are needed to explore potential interactions between APOA4 genotypes and metabolic/oxidative stress components of the diabetic milieu leading to rapid progression of atherosclerosis. Show less