CD36 gene variants and their association with type 2 diabetes in an Indian population.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is a multifactorial disease resulting from ineffective use of insulin in the body. Single nucleotide polymorphisms (SNPs) in genes for scavenger receptors such as CD36 have been implicated in the pathogenesis of atherosclerosis and cardiovascular diseases in diabetes. The present study evaluated the effect of genetic polymorphisms of the CD36 gene on the risk of developing T2DM. Four SNPs in the CD36 gene (-178A→C in the promoter region, rs1984112 [A→G in exon 1A], rs1527479 [T→C in intron IB], and rs3211938 [T→G in exon 10]) were screened in T2DM patients and healthy controls (n=100 each). MATERIALS AND METHODS: Analysis of CD36 gene polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism. Statistical analysis was done by Fisher's exact test and χ² statistics using SPSS version 15.0 software (SPSS, Inc., Chicago, IL), whereas SHEsis software (available at http://analysis.bio-x.cn/myAnalysis.php ) was used for haplotype analysis. RESULTS: There was genotypic association of rs3211938 (T→G) polymorphism with T2DM (P=0.046), whereas rs1984112 (A→G) and rs1527479 (T→C) SNPs showed no association. The minor alleles of SNPs ("G" of rs1984112, "C" of rs1527479, and "G" of rs3211938) showed significant association with clinical profiles in T2DM patients (P<0.05). Analysis also showed that the "GCG" haplotype had a significant association with T2DM (P=0.026; odds ratio=3.12; 95% confidence interval 1.089-8.939). Significant association of the CD36 gene was confirmed by linkage disequilibrium patterns. CONCLUSIONS: The CD36 variants may help to determine the T2DM susceptibility in the North Indian population. However, genotyping of variants in more individuals and studies in other populations will be required to validate the results and ethnic variations.

Association between circulating leptin and insulin resistance, the lipid profile, and metabolic risk factors in North Indian adult women.

Leptin plays an important role in the regulation of body weight and operates by inhibiting food intake and stimulating energy expenditure. The purpose of the present study was to ascertain the relationship between serum leptin levels and the lipid profile, insulin resistance, and metabolic risk factors in North Indian adult women. In a transactional case-control study of 390 women, subjects were 186 women with metabolic syndrome according to National Cholesterol Education Program Adult Treatment Panel (NCEP-ATP) guidelines and 204 healthy control women without metabolic syndrome, all of whom were between 20-40 years of age. Circulating leptin levels were determined by sandwich enzyme-linked immunosorbent assay, insulin resistance was determined by homeostasis model assessment for insulin resistance (HOMA-IR), and the lipid profile was determined using an enzymatic method. Results indicated that circulating leptin (13.38 ± 9.00 vs. 8.16 ± 6.31 ng/mL, p < 0.001), HOMA-IR (2.68 ± 2.05 vs. 1.72 ± 1.20, p < 0.001), the lipid profile, and other metabolic risk factors (waist circumference, waist-to-hip ratio, body mass index, and fasting plasma insulin) were significantly higher in women with metabolic syndrome than in women without the syndrome (p < 0.001). Further, in women with metabolic syndrome serum leptin was significantly (p < 0.05 or p < 0.001) and positively correlated with HOMA-IR (p = 0.000) and other metabolic risk factors but negatively correlated with fasting plasma glucose, triglycerides, and high-density lipoprotein cholesterol. Circulating leptin was found to be significantly associated with hyperlipidemia, insulin resistance, and other metabolic risk factors in North Indian adult women.