Yuuka Mukai*, Saori Kataoka and Shin Sato Pages 824 - 832 ( 9 )
Background: Chronic hyperglycemia is known to be a high-risk factor for progressive chronic liver diseases, such as abnormal lipid metabolism. The activation of AMP-activated protein kinase (AMPK) has a beneficial effect on dyslipidemia. Polyphenols derived from various plants are involved in AMPK activation.
Objective: We investigated the effects of polyphenol-containing sorghum (Sorghum bicolor) extract (SE) on plasma lipid metabolism and macrophage infiltration, and measured the expression and phosphorylation of AMPK and acetyl-CoA carboxylase (ACC) in diabetic rat livers.
Method: Streptozotocin-induced diabetic rats received 0, 50, or 250 mg/kg of SE orally for 4 weeks. Blood chemistry, total and phosphorylated protein levels of AMPK and ACC, sterol regulatory element-binding protein-1c (SREBP-1c) mRNA and protein levels, and macrophage infiltration in the livers were examined.
Results: Plasma glucose and triacylglycerol levels, which were increased in the untreated diabetic rats, were significantly lower in the 250 mg/kg SE-treated diabetic rats. AMPK and ACC phosphorylation levels were significantly increased in the 250 mg/kg SE-treated diabetic rats compared with those in the untreated rats. There was no difference in the hepatic expression of SREBP-1c between the diabetic rat groups. Macrophage infiltration in the liver was suppressed by 250 mg/kg of SE-treatment.
Conclusion: These data suggest that SE treatment may affect plasma lipid metabolism and chronic inflammation by upregulating phosphorylation of AMPK and ACC in diabetic rat livers.
Acetyl-CoA carboxylase, AMP-activated protein kinase, lipid metabolism, liver, macrophage infiltration, Sorghum bicolor, streptozotocin-induced diabetic rats.
Department of Food Hygiene and Function, School of Nutrition and Dietetics, Faculty of Health and Social Work, Kanagawa University of Human Services, Kanagawa, Department of Nutrition, Aomori University of Health and Welfare, Aomori, Department of Nutrition, Aomori University of Health and Welfare, Aomori