Effects of Chinese medicine Tongxinluo on hyperglycemia and beta-cell damage in streptozotocin-induced diabetic rats.
BACKGROUND
Oxidative stress has been implicated in the onset and progression of diabetes. Tongxinluo is a traditional Chinese medicine with potent antioxidant properties. The aim of this study was to test the hypothesis that pretreatment with Tongxinluo has similar effects as melatonin on preventing hyperglycemia and beta-cell damage in a rat model of streptozotocin (STZ)-induced diabetes.


METHODS
Forty male Sprague Dawley rats were randomly assigned to four groups (n = 10 each): normal control (NC) group; STZ group (70 mg/kg, i.p.); Tongxinluo (1.0 g×kg(-1)×d(-1)) pretreated (TXL + STZ) group and melatonin (200 µg×kg(-1)×d(-1)) pretreated (MLT + STZ) group. Tongxinluo and melatonin were administered by gavage beginning 8 days before STZ injection and continuing until the end of the study (15 days after STZ administration). Blood glucose levels and body weights, malondialdehyde (MDA), and reduced glutathione (GSH) levels were measured, and immunofluorescence studies were performed in all of the groups.


RESULTS
Pretreatment with Tongxinluo, as with melatonin, attenuated severe hyperglycemia and weight loss induced by STZ. In pancreatic homogenates, MDA levels were significantly lower and GSH levels were significantly higher in Tongxinluo pretreated group and in melatonin pretreated group than those in STZ group. Values of insulin staining were significantly improved in Tongxinluo pretreated group and in melatonin pretreated group as compared with those in STZ group.


CONCLUSIONS
Tongxinluo, as melatonin, prevented hyperglycemia and beta-cell destruction induced by STZ in rats through reducing oxidative stress in pancreatic tissues. Tongxinluo may provide an alternative therapy for the prevention and treatment of diabetes.
Department of Endocrinology and Metabolism, Peking University People's Hospital, Peking University Diabetes Center, Beijing 100044, China.
Huai-Qing
HQ
Wang
Jun-Jie
JJ
Zou
Xiang-Hai
XH
Zhou
Li-Nong
LN
Ji
Zhi-Min
ZM
Liu
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D001835:Body Weight; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy* / Q000378:metabolism; D004365:Drugs, Chinese Herbal / Q000627:therapeutic use*; D005455:Fluorescent Antibody Technique; D006943:Hyperglycemia / Q000188:drug therapy*; D008297:Male; D018384:Oxidative Stress; D051381:Rats; D017207:Rats, Sprague-Dawley; D013311:Streptozocin
D001786:Blood Glucose; D004365:Drugs, Chinese Herbal; C513941:tongxinluo; D013311:Streptozocin