Effects of Green Tea Polyphenol and Vitamin C on Type 2 Diabetic Rats Induced by Low Dose Streptozotocin Following High Fat Diet

고지방식이와 저용량 스트렙토조토신으로 유도된 2형 당뇨병 흰쥐에서 녹차 폴리페놀과 비타민 C 병합 투여 효과

  • Lee, Byoung-Rai (Department of Molecular Biology & Biochemistry, College of Medicine Chosun University) ;
  • Yang, Hoon (Department of Molecular Biology & Biochemistry, College of Medicine Chosun University) ;
  • Park, Pyoung-Sim (Department of Food Nutrient and Culinary, Chosun College of Science & Technology)
  • 이병래 (조선대학교 의과대학 생화학분자생물학교실) ;
  • 양훈 (조선대학교 의과대학 생화학분자생물학교실) ;
  • 박평심 (조선이공대학교 식품영양조리과학과)
  • Received : 2015.09.30
  • Accepted : 2015.11.23
  • Published : 2016.02.29


This study investigated the effects of green tea polyphenol and vitamin C on type 2 diabetes mellitus by administering polyphenon 60 (P60) and sodium ascorbate (SA) to diabetic rats induced by high fat diet/low-dose streptozotocin. The experimental group was divided into five different groups: non-diabetic control group (NC), diabetes control group (DC), diabetes+P60 group (DM+P60), diabetes+SA group (DM+SA), and diabetes+P60+SA group (DM+P60+SA). P60 and SA were dissolved in 0.1% drinking water. After P60 and SA were administered for 16 weeks, fasting blood glucose, plasma insulin, serum triglyceride, blood urea nitrogen (BUN), and creatinine levels as well as kidney alkaline phosphatase (AP) and ${\gamma}$-glutamyltranspeptidase (GGT) activities were measured. Fasting blood glucose level increased 5-fold in the DC group compared to the NC group. In the DM+P60 group, fasting blood glucose level decreased by 14%. In the DM+P60+SA group, fasting blood glucose level decreased by 28% compared to the DC group, whereas the DM+SA group did not show any significant difference. The homeostasis model assessment for insulin resistance index increased in the DC group and decreased in the DM+P60+SA group compared to the DC group. Serum creatinine level increased in the DC group, but decreased by 17% in the DM+P60 group and by 43% in the DM+P60+SA group compared to the DC group. The serum BUN level increased in the DC group, but decreased by 41% in the DM+P60+SA group compared to the DC group. Kidney GGT and AP activities decreased in the DC group compared to the NC group; however, they were reversed by DM+P60+SA group. These results show that combined administration of both green tea polyphenol and vitamin C had better effects on improving blood glucose level, insulin resistance, serum triglyceride level, and protecting kidneys than administration of either green tea polyphenol or vitamin C alone in the context of type 2 diabetes.


Supported by : 조선대학교


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