The effects of rexinoids and rosiglitazone on body weight and uncoupling protein isoform expression in the Zucker fa/fa rat

Abstract Agonists for the retinoid X receptor (RXR), the rexinoids, and the peroxisome proliferator-activated receptor gamma (PPAR γ), the thiazolidinediones, are effective in the treatment of insulin resistance in rodent models by enhancing insulin action and improving glycemic control. In the present study, we compared the effects of rexinoids and a thiazolidinedione on body weight and mitochondrial uncoupling protein (UCP) isoform mRNA expression in the obese Zucker fa/fa rat. Long-term (2 weeks) oral treatment with the rexinoids LG100268 and LG100324 reduced food intake and body weight gain, whereas rosiglitazone (BRL49653) tended to increase both food intake and weight gain. LG100268 and LG100324 increased brown adipose tissue (BAT) UCP-1 mRNA content by 2.7-fold ( P P P P P P P