OBJECTIVETo study the effects of conjugated linoleic acid (CLA) on expression of glucose transporter 4 (GLUT4) protein in skeletal muscle of insulin resistant rat, and explore the mechanism of resisting diabetes by CLA.

METHODSMale Wistar rats were randomly separated into control group, high-fat group and high fat plus CLA group (0.75 g%, 1.50 g%, 3.00 g% by deit weight), and the effects of CLA on blood glucose and insulin levels of insulin resistant rat were observed , by using Western blot technique to measure the expression level of GLUT4 protein in skeletal muscle of insulin resistant rat.

RESULTSThe serum insulin and glucose levels of obese rats were (11.11 +/- 2.73) microU/ml, and (5.09 +/- 0.66) mmol/L, the supplement of CLA might decrease the hyperinsulinemia and hyperglycemia, and in CLA groups (0.75 g%, 1.50 g%, 3.00 g% by deit weight) the serum insulin was (6.99 +/- 1.77) microU/ml, (7.36 +/- 1.48) microU/ml and (7.85 +/- 1.60) microU/ml (P < 0.05), and the glucose levels were (4.28 +/- 0.72) mmol/L, (4.18 +/- 0.55) mmol/L (P < 0.05), (4.06 +/- 0.63) mmol/L (P < 0.05) respectively. The expression of GLUT4 protein in skeletal muscle of rat fed with high fat diet were decreased as compared with those fed with basic deit, and CLA might increase the expression of GLUT4 protein in skeletal muscle fed with high fat diet.

CONCLUSIONSCLA improve the insulin resistance of obese rat, possibly acting through increasing the expression of GLUT4 protein in skeletal muscle of rat fed with high fat diet.