Fig. 1

The experimental protocol for studying the effect of piperine on the development of insulin resistance in MSG-obese mice. MSG-obese mice were obtained by s.c. injection of MSG (4 g/kg/d) to newborn mice for 7 successive days. After 24 weeks, the obese MSG mice were divided into three groups and treated with piperine (40 mg/kg/d), metformin (150 mg/kg/d), or vehicle, respectively, for 10 weeks