Authors : Turan Karaca, Mecit Yoruk, Ibrahim H. Yoruk and Sema Uslu
Abstract: This study investigated the effects of oral administration of extract of green tea (Camellia sinensis) and ginseng (American ginseng-Panax quinquefolium L.), given alone or together, on pancreatic β-cells, blood glucose, insulin, cholesterol and triglyceride levels in rats with experimental diabetes induced by a single injection of Streptozotocin (STZ) (60 mg kg-1, i.p.). Fifty adult Wistar Albino rats were used, 10 in each of these five treatment groups: Group A: healthy controls, Group B: STZ-induced diabetes (untreated), Group C: STZ-induced diabetes plus green tea extract (100 mg/kg/daily), Group D: STZ-induced diabetes plus ginseng root (400 mg/kg/daily) and Group E: STZ-induced diabetes plus ginseng root + green tea extracts as before. At the end of the 6 weeks experiment, blood samples were analysed for blood glucose, insulin, cholesterol and triglyceride levels and samples of pancreatic tissue were examined histochemically and immunohistochemically for endocrine islets and β-cells. Overall, body weight decreased in groups B and C, serum insulin concentrations decreased slightly in groups C-E and total triglyceride levels of blood decreased significantly (p<0.05) in groups B and C compared with control, D and E groups. Histopathological examination showed that degenerative changes in pancreatic β-cells in STZ-treated rats were minimised to near normal morphology by administration of ginseng (Group D) and ginseng+green tea (Group E) and there was increased intensity of immunohistochemical staining for insulin in these groups. Degeneration of islets of Langerhans β-cells and weak insulin staining was observed for green tea alone (Group C). These findings demonstrate that ginseng or combined ginseng + green tea decreases blood glucose levels in diabetic rats and increases preservation of β-cells, perhaps by lowering oxidative stress.
Turan Karaca, Mecit Yoruk, Ibrahim H. Yoruk and Sema Uslu, 2010. Effects of Extract of Green Tea and Ginseng on Pancreatic Beta Cells and Levels of Serum Glucose, Insulin, Cholesterol and Triglycerides in Rats with Experimentally Streptozotocin-Induced Diabetes: A Histochemical and Immunohistochemical Study. Journal of Animal and Veterinary Advances, 9: 102-107.