Human RETN peptide

Aims/Introduction: Resistin, an inflammatory cytokine, might be involved in the development of atherosclerosis. In a recent paper, we showed that resistin polymorphism might be a risk marker for stroke susceptibility in Japanese type 2 diabetic patients. We tested whether the serum resistin levels might be also a risk marker of stroke independently from RETN polymorphism. Materials and Methods: Type 2 diabetic outpatients from our hospitals were enrolled. Patients (n = 89) with a history of coronary heart disease and stroke, and randomly selected controls (n = 178) matched for sex and age, but without a history of coronary heart disease and stroke, were examined for polymorphism -420 (C > G) and cytokines levels. Results: Serum resistin levels were significantly higher in patients with cardiovascular diseases (CVD) than in those without CVD (P = 0.024), and were highest in patients with stroke among the CVD. In multiple logistic regression analysis, serum resistin levels was an independent risk marker of stroke even after adjusted by RETN polymorphism, age, sex, body mass index, HbA(1c), systolic and diastolic blood pressure, triglyceride, low density lipoprotein cholesterol, high density lipoprotein cholesterol, creatinine, history of coronary heart disease, treatment of insulin, sulfonylurea and aspirin (odds ratio 1.33, 95% confidence interval [CI] 1.02-1.73, P = 0.039). The enrolled patients were divided by their serum resistin levels (high or low group) and their genotypes (CC, CG, GG at -420) into six groups. Patients with the GG genotype and high resistin levels showed the highest odds ratio, 5.69 (95% CI 1.24-26.1), compared with the group with CC and low levels. Conclusions: The results suggest that serum resistin levels might be a good marker of susceptibility to stroke as well as RETN polymorphism. (J Diabetes Invest, doi: 10.1111/j.2040-1124.00040.x, 2010)

OBJECTIVE-The RETN gene encodes the adipokine resistin. Associations of RETN with plasma resistin levels, type 2 diabetes, and related metabolic traits have been inconsistent. Using comprehensive linkage disequilibrium mapping, we genotyped tag single nucleotide polymorphisms (SNPs) in RETN and tested associations with plasma resistin levels, risk of diabetes, and glycemic traits. RESEARCH DESIGN AND METHODS-We examined 2,531 Framingham Offspring Study participants for resistin levels, glycemic phenotypes, and incident diabetes over 28 years of follow-up. We genotyped 21 tag SNPs that capture common (minor allele frequency >0.05) or previously reported SNPS at r(2) > 0.8 across RETN and its flanking regions. We used sex- and age-adjusted linear mixed-effects models (with/without BMI adjustment) to test additive associations of SNPs with traits, adjusted Cox proportional hazards models accounting for relatedness for incident diabetes, and generated empirical P values (P-e to control for type I error. RESULTS-Four tag SNPs (rs1477341, rs4804765, rs1423096, and rs10401670) on the 3' side of RETN were strongly associated with resistin levels (all minor alleles associated with higher levels, P-e<0.05 after multiple testing correction). rs10401670 was also associated with fasting plasma glucose (P-e = 0.02, BMI adjusted) and mean glucose over follow-up (P-e = 0.01; BMI adjusted). No significant association was observed for adiposity traits. On meta-analysis, the previously reported association of SNP -420C/G (rs1862513) with resistin levels remained significant (P = 0.0009) but with high heterogeneity across studies (P < 0.0001). CONCLUSIONS-SNPs in the 3' region of RETN are associated with resistin levels, and one of them is also associated with glucose levels, although replication is needed. Diabetes 58: 750-756, 2009