Phosphatase and tension homolog overexpression in insulin resistant diabetic adipose tissue / 中国医学科学杂志(英文版)

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the expression of phosphatase and tension homolog (PTEN) in adipose tissue of KKAy diabetic mice, a mouse model of type 2 diabetes.</p><p><b>METHODS</b>KKAy diabetic mice were fed with high fat diet for 4 weeks. After blood glucose met the criteria of diabetes (over 16.7 mmol/L), mice were randomly divided into 3 groups a control group (without any treatment), a rosiglitazone group (treated with rosiglitazone 12.5 mg/kg.d once per day), and a metformin group (treated with metformin 3 g/kg.d twice daily). After 4 weeks, we then determined the expression of PTEN and phosphoserine 473-Akt (pS473-Akt) in the epididymal adipose tissue with Western blots. The mice in each group were further divided into the insulin (-) subgroup and insulin (+) subgroup, which were intraperitoneally injected with saline and insulin (5 mU/g body weight), respectively.</p><p><b>RESULTS</b>The expression of PTEN was elevated in the epididymal adipose tissue obtained from KKAy diabetic mice compared with that from the C57BL/6J mice (P<0.001). In accordance with the enhanced expression of PTEN, the level of pS473-Akt stimulated by insulin was decreased in the adipose tissue of KKAy mice compared to the C57BL/6J mice (P<0.001). Treatment with the insulin-sensitizing agents, rosiglitazone and metformin did not inhibit the elevated expression of PTEN in adipose tissue of KKAy diabetic mice.</p><p><b>CONCLUSION</b>PTEN may play an important role in the development of insulin resistance in adipose tissue of type 2 diabetes mice model.</p>