Level of serum IL-12 and its correlation with endothelial dysfunction, insulin resistance, proinflammatory cytokines and lipid profile in newly diagnosed type 2 diabetes.
This study was an attempt to evaluate and correlate serum interleukin-12 (IL-12) with different circulating markers in newly diagnosed type-2 diabetes mellitus (T2DM) for possible progression of atherosclerosis. For this study, we recruited 1968 family members of diabetics and 349 had abnormal glucose. Out of 349 subjects, 197 were T2DM as per American Diabetes Association guidelines and further investigated for cardiovascular abnormalities. 63 T2DM have high sensitive C-reactive protein (hsCRP)>3.0mg/l and cardiovascular complications. Overall, 150 subjects, 50 healthy, 50 T2DM (D1) and 50 T2DM with cardiovascular complications (D2) were enrolled and investigated for soluble markers. The levels of serum glucose, proinflammatory cytokines (IL-6, IL-12, tumor necrosis factor), endothelial dysfunction markers [vascular cell adhesion molecule-1 (VCAM-1), inter-cellular adhesion molecule-1 (ICAM-1), nitric oxide] and lipid abnormality were highest in D2 group. Correlation and regression study showed that IL-12 was dependent on hsCRP, insulin resistance, VCAM-1, ICAM-1 and lipids. The multivariate stepwise regression analysis demonstrates that hsCRP contributes significantly for variance of IL-12. This study reveals that, even first-time diagnosis of T2DM, subjects with higher insulin resistance and abnormal lipids have elevated IL-12, endothelial dysfunction and proinflammatory markers. Further increased hsCRP enhance IL-12 which up-regulate cardiovascular disease progression.