Black Tea Inhibits Small Intestinal α-Glucosidase Activity in db/db Mouse
10.1625/jcam.11.25
- VernacularTitle:紅茶は db/db マウスの小腸 a-グルコシダーゼ活性を阻害する
- Author:
Masaki IGARASHI
;
Takashi SATOH
;
Hiroshi YAMASHITA
;
Kazuhiro WATANABE
- Publication Type:Journal Article
- Keywords:
black tea;
diabetes mellitus;
α-glucosidase;
db/db mouse;
postprandial hyperglycemia
- From:Japanese Journal of Complementary and Alternative Medicine
2014;11(1):25-33
- CountryJapan
- Language:Japanese
-
Abstract:
The inhibitory effects of the freeze-dried powder of the aqueous extract of black tea leaf (JAT) on α-glucosidase activity were investigated. We initially examined the effects of JAT addition on yeast α-glucosidase activity. JAT significantly and dose-dependently inhibited α-glucosidase activity and more strongly inhibited the activity than acarbose, the positive control. Then, we examined the effects of oral administration of JAT on sucrose tolerance in type 2 diabetes mellitus model db/db mice. Both JAT and acarbose administered groups showed a dose-dependent decrease in plasma glucose levels after the sucrose loading compared with the control group. Notable was that the plasma glucose levels of the 500 mg/kg JAT administered group exhibited a significant decrease 30 min or longer after the sucrose loading. On the other hand, no significant difference in plasma insulin levels was seen between the JAT administered group and the control group. We also measured small intestinal sucrase activity in db/db mouse at 30 min after JAT oral administration. Compared to control mice, small intestinal sucrase activity was significantly decreased in the 500 mg/kg JAT administered mice. These findings indicate that JAT may be a useful natural material for the prevention and therapy of type 2 diabetes mellitus.
