Type 2 diabetes and metabolic syndrome - adipokine levels and effect of drugs

Type 2 diabetes mellitus (T2DM) is a consequence of complex interactions among multiple genetic variants and environmental risk factors. This complex disorder is also characterized by changes in various adipokines. In this study, our objective was to estimate the levels of adiponectin, leptin, and resistin (ALR) in T2DM patients, besides studying the effect of various drugs on their levels. Study participants included 400 diabetic and 300 normal patients from the Department of Endocrinology and Department of Biochemistry, Govt Medical College Srinagar. Subjects were categorized under various groups, i.e., Group 1 (metformin treated) and Group 2 (glimepiride treated), and cases were also categorized as obese with T2DM (Group A), obese without T2DM (Group B), and T2DM only (Group C). The serum ALR levels were estimated by ELISA (Alere), and biochemical parameters were also evaluated before and after treatment. Adiponectin levels were found to be significantly lower in T2DM cases as compared to controls (125.5 versus 22.5 +/- 7.9g/ml), while leptin and resistin levels were found to be significantly higher than controls (14.3 +/- 7.4 versus 7.36 +/- 3.73ng/ml) (13.4 +/- 1.56 versus 7.236 +/- 2.129pg/ml). Taking the effect of drugs into consideration, the effect on adiponectin and resistin levels was found to be highly significant in Group 2 before and after treatment (11 +/- 5 versus 19.2 +/- 4.5g/ml) (13.6 +/- 2.5 versus 7.3 +/- 2.9pg/ml), while more effect was observed in leptin among Group 1 (metformin)-treated cases (27 +/- 15ng/ml versus 15 +/- 15ng/ml). Further the adiponectin levels were found to be significantly lower in Group B, while leptin and resistin levels were found to be significantly higher among obese cases when compared to T2DM cases only. Glimepiride also shows more effect on FBG, HbA1c% levels, while metformin shows more effect on Lipid profile levels. From the study, it can be concluded that ALR levels are affected by use of antidiabetic drugs among which glimepiride shows more effect on adiponectin and resistin levels, while leptin gets affected more by metformin. It can also be proposed that ALR levels are not affected by diabetes only, suggesting that their alterations in T2DM may be due to obesity as we observed more ALR changes in obese cases when compared to T2DM cases, and so there might be an important link between adiposity and insulin resistance.