[Antagonism effects of green tea against microcystin induced oxidant damage on liver and kidney].
OBJECTIVE
To evaluate the antagonism effects of green tea (GT) against microcystin LR (MC-LR) induced hepatotoxicity and nephrotoxicity in mice.


METHODS
All 40 male mice were randomly divided into four groups. Mice in group III and IV were pretreated with green tea for free drink at doses of 2 g/L and 12 g/L prior to MC-LR intoxication, for consecutively 18 days. The toxin treatment mice were administered continually intraperitoneal injections of MC-LR at a dose of 10 microg x kg(-1) x d(-1) bw from day 6th till sacrifice, continually 13 days. Mice were sacrificed and immediately subjected to necropsy, and the body weight, relative organ weight, serum biochemical parameters, antioxidant enzyme levels (SOD and GSH), lipid peroxidation products (MDA) and histopathology were systematically evaluated.


RESULTS
MC-LR exposure led to increase the oxidative stress and organ injury was significantly observed through biochemical parameters and microscopic evaluation. However, high dose of GT pretreatment caused a significant elevation in serum GSH and SOD levels, and a decrease of serum MDA level as compared with MC-LR control. The mean values of GSH and SOD activities were separately 467.29 mg/L and 139.22 U/ml in group IV. Subsequently, GT pretreatment obviously diminished the serum ALT, AST and Cr activities. Those pathological damages in liver and kidney, were to a certain extent, lessened in GT pretreatment mice in correlation with the biochemical parameters.


CONCLUSIONS
GT might elevate antioxidant defense system, clean up free radicals, lessen oxidative damages and protect liver and kidney against MC-LR induced toxicity.
Xu
Chuan
C
Department of Environmental Hygiene, School of Military Preventive Medicine, The Third Military Medical University, Chongqing 400038, China. wqshu@mail.tmmu.com.cn
Shu
Wei-Qun
WQ
Cao
Jia
J
Qiu
Zhi-Qun
ZQ
Zhao
Qing
Q
Chen
Ji-An
JA
Zeng
Hui
H
Fu
Wen-Juan
WJ
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D056486:Chemical and Drug Induced Liver Injury; D005609:Free Radicals / Q000378:metabolism; D007674:Kidney Diseases / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D008107:Liver Diseases / Q000378:metabolism* / Q000473:pathology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D052998:Microcystins / Q000633:toxicity; D018384:Oxidative Stress; D013662:Tea
D000975:Antioxidants; D005609:Free Radicals; D052998:Microcystins; D013662:Tea; C078588:microcystin