Corn gluten hydrolysate and capsaicin have complimentary actions on body weight reduction and lipid-related genes in diet-induced obese rats

The aim of this study was to test the hypothesis that a combination of corn gluten hydrolysate (CGH) and capsaicin may have an additive or synergistic effect on body weight reduction. For 13 weeks, male Sprague-Dawley rats were provided a diet to induce obesity. Afterward, the rats were randomly divided into 5 dietary groups: the normal control (n =5), the high-fat control (n = 8) the high-fat diet (HFD) containing 35% CGH (n = 7), the HFD containing 0.02% capsaicin (HF-P) (n = 8), and the HFD containingboth CGH and capsaicin (HF-CP) (n = 7) for an additional 4 weeks. Administration of CGH plus capsaicin, along with a HFD, led to significant decreases in body weight, fat mass, lipids in the liver, and plasma leptin as well as increases in plasma regulation of peroxisome proliferator-activated receptor a, camitine palmitoyltransferase 1a,adiponectin. The pattern of gene expression was different in each target organ. In the liver, up-regulation of peroxisome proliferator-activated receptor a, camitine palmitoyltransferase 1a, and acyl-coenzyme A oxidase was found in the HF-CP group. In contrast, down-regulation of insulin receptor and uncoupling protein 3 was found in the HF-P group only, whereas up-regulation of the glucose transporter 4 gene was observed in both the HF-CF and HF-P groups. In adipose tissue, up-regulation of peroxisome proliferator-activated receptor gamma and hormone-sensitive lipase was only found in the HF-CP group. In summary, this study suggests that CGH and capsaicin perform complementary actions on food intake, lipid metabolism, and insulin sensitivity by a coordinated control of energy metabolism in the liver, adipose tissue, and skeletal muscle, thus exerting an additive effect on body weight reduction. (C) 2014 Elsevier Inc. All rights reserved.