Abstract

BACKGROUND
Interleukin(IL)-6 is a cytokine that is produced from immune cells and adipose tissue. It is thought to be a factor to explain the link between insulin resistance and inflammation, and it is also thought to be involved in glucose metabolism and lipid metabolism. We observed the frequency of the G174C polymorphism in the IL-6 gene promoter region in Korean women and we investigated the association of fasting glucose, insulin resistance indices and metabolic syndrome. METHODS: Measurements of the blood pressure, body fat, fasting glucose, insulin, lipid profiles and anthropometric measurements were done for 268 Korean women(mean age 51.4yrs, range 37~73yrs). Homeostasis model assessement(HOMA) and the quantitative insulin sensitivity check index(QUICKI) were calculated and the presence of metabolic syndrome was assessed according to ATP III criteria. Genotyping was done with the PCRRFLP method on the blood samples of the participants. RESULTS: The allele frequencies were 0.965 for the G allele and 0.035 for the C allele, and they were in Hardy-Weinberg equilibrium(P=0.50). The fasting insulin level and HOMA were significantly higher and the QUICKI was significantly lower in the C allele carriers compared with non-carriers. Although the prevalence of metabolic syndrome was not significantly different according to the different genotypes, among the individual components, the prevalence of hypertriglyceridemia was significantly higher in the C allele carriers compared with the non-carriers. There were no differences in the prevalence of normoglycemia, fasting hyperglycemia and provisional diabetes according to the different genotypes. CONCLUSION: The G174C polymorphism in The IL-6 promoter region was not frequently observed in Korean women. The insulin resistance indices were higher in the C allele carriers compared with the non-carriers. Although the prevalence of metabolic syndrome was not associated with the polymorphism, the prevalence of hypertriglyceridemia was higher in The C allele carriers, suggesting that it is possibile for candidate gene of insulin resistance

• Keywords: Interleukin-6;Insulin resistance;Metabolic syndrome;Promoter;Genetic polymorphism