Inverse correlation between serum levels of selenoprotein P and adiponectin in patients with type 2 diabetes

Background

We recently identified selenoprotein P (SeP) as a liver-derived secretory protein that causes insulin resistance in the liver and skeletal muscle; however, it is unknown whether and, if so, how SeP acts on adipose tissue. The present study tested the hypothesis that SeP is related to hypoadiponectinemia in patients with type 2 diabetes.

Methodology/Principal Findings

We compared serum levels of SeP with those of adiponectin and other clinical parameters in 36 patients with type 2 diabetes. We also measured levels of blood adiponectin in SeP knockout mice. Circulating SeP levels were positively correlated with fasting plasma glucose (r?=?0.35, P?=?0.037) and negatively associated with both total and high-molecular adiponectin in patients with type 2 diabetes (r?=??0.355, P?=?0.034; r?=??0.367, P?=?0.028). SeP was a predictor of both total and high-molecular adiponectin, independently of age, body weight, and quantitative insulin sensitivity index (β?=??0.343, P?=?0.022; β?=??0.357, P?=?0.017). SeP knockout mice exhibited an increase in blood adiponectin levels when fed regular chow or a high sucrose, high fat diet.

Conclusions/Significance

These results suggest that overproduction of liver-derived secretory protein SeP is connected with hypoadiponectinemia in patients with type 2 diabetes.