[Wheat bran reduces oxidative stress and promotes glucagon-like peptide-1 secretion in high-fat-fed rats]

This study aimed to investigate the effects of wheat bran intervention on oxidative stress status and glucagon-like peptide-1(GLP-1) secretion in rats fed a high-fat diet(HFD).

Thirty-two specific pathogen-free(SPF) Sprague-Dawley(SD) rats were acclimatized for 1 week and then randomly assigned to 4 groups(n=8 per group) by body weight: normal control group(NC, fed a standard chow), high-fat diet group(HF, fed a high-fat diet), low-dose wheat bran intervention group(HF+LWB, HFD supplemented with 10% dietary fiber from wheat bran), and high-dose wheat bran intervention group(HF+HWB, HFD supplemented with 15% dietary fiber from wheat bran). The intervention lasted for 12 weeks. At the end of the intervention, animals were euthanized, and blood samples were collected. Outcome measurements included: fasting blood glucose(FBG), fasting insulin(FINS); oxidative stress-related indices(superoxide dismutase(SOD), glutathione peroxidase(GSH-Px), malondialdehyde(MDA)) in serum and tissues(liver, colon); GLP-1 levels in serum and colon tissue; and histopathological changes of liver and colon tissues via hematoxylin-eosin(HE) staining.

Compared with the NC group, the HF group exhibited significant increases in body weight, Lee's index, and liver weight(P<0.05), elevated serum FBG and FINS levels(P<0.05), decreased activities of SOD and GSH-Px in serum and tissues, increased MDA content(P<0.05), and reduced serum GLP-1 levels(P<0.05). Following wheat bran intervention, both wheat bran groups showed marked reductions in body weight and liver weight(P<0.05), enhanced SOD and GSH-Px activities, decreased MDA content(P<0.05), and increased GLP-1 secretion-with the high-dose group demonstrating more pronounced effects. Histological analysis revealed hepatic steatosis and varying degrees of colonic mucosal damage in the HF group, whereas these pathological changes were significantly ameliorated after wheat bran intervention.

Wheat bran intervention ameliorates glucose metabolism disorders in high-fat-fed rats, alleviates oxidative stress in the liver and intestine, and promotes GLP-1 secretion, thereby improving obesity.