Journal of Medical Biochemistry (Jan 2016)
High molecular weight adiponectin levels are neither influenced by adiponectin polymorphisms nor associated with insulin resistance in mixed-ancestry hyperglycemic subjects from South Africa
Abstract
Background: High molecular weight (HMW) adiponectin has antiatherogenic, antiinflammatory and antidiabetic properties and these effects have been linked to its effect on high density lipoprotein cholesterol (HDL-c). Single nucleotide polymorphisms (SNPs) in the adiponectin gene influence adiponectin levels. We examined the relationship between HMW-adiponectin levels and cardiometabolic traits in normoand hyperglycemic mixed ancestry South Africans and correlated these levels to two common polymorphisms. Methods: HMW-adiponectin was determined in 101 subjects from the Cape Town Bellville South community-based study on a mixed ancestry population. Comparisons were made between individuals with normoand hyperglycemia. Two common SNPs, ADIPOQ SNPs rs17300539 and rs266729, known to affect adiponectin levels were also tested for. Levels of HMW-adiponectin were then correlated with cardiometabolic traits in all groups. Results: Levels of HMW-adiponectin were not significantly different in the normoand hyperglycemic groups (median 11.6 vs. 10.5 mg/mL, p=0.3060) and in men and women (8.44 vs. 11.34 mg/mL, p = 0.67). ADIPOQ SNPs rs17300539 and rs266729 did not influence levels of HMW-adiponectin. Robust correlation analyses revealed a significant positive correlation between HMW-adiponectin and HDL-c (r= 0.45; 95%CI: 0 .2 7 -0 .5 9 ), similarly in normoand hyperglycemic participants (p> 0.99). This association was substantially attenuated in robust linear regressions adjusted for age, gender and adiposity. Conclusions: Adiponectin levels in this population were not determined by the commonest SNPs of the adiponectin gene, were unaffected by glycemic status; but were significantly correlated with HDL-c levels. Previous studies have attributed some of the beneficial effects of adiponectin to its effect on HDL-c.