Rice bran water extract attenuates pancreatic abnormalities in high-fat diet-induced obese rats

Purpose: To investigate the protective potential of rice bran water extract (RBE) from Khao Dawk Mali 105 on pancreatic abnormalities in high-fat diet (HFD)-induced obese rats. Methods: Male Sprague-Dawley rats were divided into 4 groups: control group, HFD group, and HFD group treated with RBE at 2,205 or 4,410 mg/kg/day. After 4 weeks, body weight, glucose homeostatic parameters, and pancreatic fat accumulation were assessed. mRNA expression levels of sterol regulatory element-binding protein-1c (SREBP-1c), insulin receptor substrate-2 (IRS-2), glucose transporter-2 (GLUT-2) and glucokinase (GK) genes in pancreas were also analyzed. Results: Compared with HFD group, two doses of RBE-treated rats significantly (p < 0.05) reversed HFD-induced obesity, hyperglycemia, impaired glucose tolerance and pancreatic triglyceride accumulation in rats. Histological examination of HFD-induced obese rats revealed fat droplets in acinar cells, but these alterations were ameliorated in RBE-treated rats. RBE treatment showed significantly (p < 0.05) decreased SREBP-1c expression, and also significantly (p < 0.05) increased IRS-2, GLUT-2 and GK expressions in pancreas. Conclusion: RBE consumption may attenuate pancreatic abnormalities by inhibiting fat accumulation, as well as enhancing insulin sensitivity and glucose sensing in the pancreas of HFD-induced obese rats. Keywords: Rice bran, Obesity, Pancreatic steatosis, Insulin signaling, Glucose sensor