title: Anti-diabetic effect of purple corn extract on C57BL/KsJ db/db mice.
abstract: OBJECTIVE
  Recently, anthocyanins have been reported to have various biological activities. Furthermore, anthocyanin-rich purple corn extract (PCE) ameliorated insulin resistance and reduced diabetes-associated mesanginal fibrosis and inflammation, suggesting that it may have benefits for the prevention of diabetes and diabetes complications. In this study, we determined the anthocyanins and non-anthocyanin component of PCE by HPLC-ESI-MS and investigated its anti-diabetic activity and mechanisms using C57BL/KsJ db/db mice.
  
  
  METHODS
  The db/db mice were divided into four groups: diabetic control group (DC), 10 or 50 mg/kg PCE (PCE 10 or PCE 50), or 10 mg/kg pinitol (pinitol 10) and treated with drugs once per day for 8 weeks. During the experiment, body weight and blood glucose levels were measured every week. At the end of treatment, we measured several diabetic parameters.
  
  
  RESULTS
  Compared to the DC group, Fasting blood glucose levels were 68% lower in PCE 50 group and 51% lower in the pinitol 10 group. Furthermore, the PCE 50 group showed 2- fold increased C-peptide and adiponectin levels and 20% decreased HbA1c levels, than in the DC group. In pancreatic islets morphology, the PCE- or pinitol-treated mice showed significant prevention of pancreatic β-cell damage and higher insulin content. Microarray analyses results indicating that gene and protein expressions associated with glycolysis and fatty acid metabolism in liver and fat tissues. In addition, purple corn extract increased the phosphorylation of AMP-activated protein kinase (AMPK) and decreased phosphoenolpyruvate carboxykinase (PEPCK), glucose 6-phosphatase (G6pase) genes in liver, and also increased glucose transporter 4 (GLUT4) expressions in skeletal muscle.
  
  
  CONCLUSIONS
  Our results suggested that PCE exerted anti-diabetic effects through protection of pancreatic β-cells, increase of insulin secretion and AMPK activation in the liver of C57BL/KsJ db/db mice.
authors: College of Food Science and Engineering, Liaoning Medical University, Jinzhou 121000, China.
authors: Bo
authors: B
authors: Huang
authors: Department of Food Science and Nutrition and Center for Aging and HealthCare, Hallym University, 1 Hallymdaehak-gil, Chuncheon, Gangwon 200-702, Korea.
authors: Zhiqiang
authors: Z
authors: Wang
authors: Institute of Natural Medicine, Hallym University Medical School, Gangwon 200-702, Korea.
authors: Jong Hyuk
authors: JH
authors: Park
authors: Division of Endocrinology and Metabolism, Department of Internal Medicine, Hallym University, Gangwon 200-702, Korea.
authors: Ok Hyun
authors: OH
authors: Ryu
authors: Division of Endocrinology and Metabolism, Department of Internal Medicine, Hallym University, Gangwon 200-702, Korea.
authors: Moon Ki
authors: MK
authors: Choi
authors: Institute of Natural Medicine, Hallym University Medical School, Gangwon 200-702, Korea. ; Department of Biochemistry, School of Medicine, Hallym University, Gangwon 200-702, Korea.
authors: Jae-Yong
authors: JY
authors: Lee
authors: Department of Food Science and Nutrition and Center for Aging and HealthCare, Hallym University, 1 Hallymdaehak-gil, Chuncheon, Gangwon 200-702, Korea.
authors: Young-Hee
authors: YH
authors: Kang
authors: Institute of Natural Medicine, Hallym University Medical School, Gangwon 200-702, Korea. ; Department of Food Science and Nutrition and Center for Aging and HealthCare, Hallym University, 1 Hallymdaehak-gil, Chuncheon, Gangwon 200-702, Korea.
authors: Soon Sung
authors: SS
authors: Lim
keywords: AMPK; Purple corn; diabetes; insulin; microarray assay