Low plasma apelin levels in newly diagnosed type 2 diabetes mellitus

Objective: To investigate blood apelin concentrations in patients with newly diagnosed and untreated type 2 diabetes mellitus (T2DM) who had no additional disorder and to investigate the association of apelin with adiponectin, body mass indexes (BMI) and insulin sensitivity. Methods: Forty patients with T2DM and 40 healthy controls were enrolled. Apelin levels were measured along with BMI, lipids, glucose, insulin and adiponectin levels, and HOMA-IR indexes. Age, sex and BMI were similar in the two groups. Results: Plasma apelin and adiponectin levels were significantly lower in the diabetic group compared to controls (p < 0.001, for both). Insulin levels and HOMA indexes were significantly higher in patients with T2DM (p < 0.001 and p = 0.001, respectively). Apelin levels were negatively correlated with age (r = - 0.315, p = 0.006), fasting blood glucose (r = -0.556, p < 0.001) and HOMA indexes (r = -0.411, p = 0.001), and positively correlated with plasma adiponectin levels (r = 0.593, p < 0.001). Plasma adiponectin was negatively correlated to plasma insulin (r = -0.379, p = 0.001), fasting glucose (r = -0.604, p < 0.001), HOMA-IR (r = -0.559, p < 0.001) and BMI (= -0.229, p = 0.04). Conclusions: Plasma apelin is reduced in newly diagnosed and untreated patients with T2DM having no confounders. Regulation of circulating apelin and adiponectin seems to be in the same manner in patients with T2DM. Dysregulation of apelin might be involved in the mechanism of establishment of overt diabetes mellitus as well as associated atherosclerotic complications.