Amelioration of gentamicin nephrotoxicity by green tea extract in uninephrectomized rats as a model of progressive renal failure.
BACKGROUND
Gentamicin (GM) is an effective antibiotic against severe infection but has limitations related to nephrotoxicity. This study investigates whether green tea extract (GTE), an antioxidant, could ameliorate the nephrotoxic effect of GM in uninephrectomized rats.


OBJECTIVE
The right kidneys of 40 rats were surgically removed and 1 week later the animals were divided into four groups (n = 10). Group 1 served as control, Group 2 as GTE group, Group 3 as GM group, and Group 4 as GM+GTE group. Kidney function, inflammatory cytokine TNF-α, oxidant and antioxidant parameters of renal tissue, as well as histopathological studies were assessed.


RESULTS
Injecting uninephrectomized rats with GM induced renal dysfunction as shown by significant elevations in serum creatinine and urea. Serum TNF-α and oxidative stress parameters (superoxide anion and lipid peroxides) were also significantly increased. On the contrary, antioxidative parameters [superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH)] were significantly decreased. Histopathological examination of renal tissue illustrated features of degeneration, marked cellular infiltration, tubular dilatation, and varying degrees of necrosis. GTE given to GM rats reduced these nephrotoxicity parameters. Serum creatinine, urea, and TNF-α were almost normalized in the GM+GTE group. The oxidative stress parameters were significantly decreased and the antioxidative parameters were significantly increased.


CONCLUSIONS
GTE ameliorates GM-induced nephrotoxicity and oxidative damage by improving antioxidant defense and tissue integrity. Further human studies are necessary to demonstrate the antioxidant effects of GTE on renal diseases. Nevertheless, green tea (GT) may offer an inexpensive, nontoxic, and effective intervention strategy in subjects with a risk for GM-induced nephrotoxicity.
Department of Urology, Zagazig University, Zagazig, Sharkia, Egypt. dr_emadsalem@yahoo.com
Emad A
EA
Salem
Neveen A
NA
Salem
Mostafa
M
Kamel
Aref M
AM
Maarouf
Nabil K
NK
Bissada
Wayne J G
WJ
Hellstrom
Mohmoud
M
Eladl
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology; D028241:Camellia sinensis; D050260:Carbohydrate Metabolism / Q000187:drug effects; D003404:Creatinine / Q000097:blood; D004195:Disease Models, Animal; D005839:Gentamicins / Q000494:pharmacology*; D007668:Kidney / Q000187:drug effects* / Q000473:pathology; D015227:Lipid Peroxidation / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects* / Q000502:physiology; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013662:Tea; D014508:Urea / Q000097:blood
D000900:Anti-Bacterial Agents; D000975:Antioxidants; D005839:Gentamicins; D010936:Plant Extracts; D013662:Tea; D014508:Urea; D003404:Creatinine