Green tea ameliorates renal oxidative damage induced by gentamicin in rats

Recent studies indicate that free radicals are important mediators of renal damage induced by gentamicin [GM], an aminoglycoside antibiotic widely used in treating severe gram-negative infections. Green tea extract [GTE] was reported to have antioxidant and free radical scavenging activities. Therefore, the aim of this work was to investigate the possible protective effect of GTE against gentamicin-induced nephrotoxicity. For this purpose, rats were divided into four groups. Group-1 [control] received normal saline. Group-2 received GTE [300 mg/kg/d, orally]. Group-3 received gentamicin [80 mg/kg/d, intraperitoneally]. Group-4 was injected with GTE plus gentamicin simultaneously. Daily urinary total protein levels were estimated to assess kidney dysfunction. The rats were sacrificed on the seventh day and kidneys were collected for histopathological studies. Blood urea nitrogen [BUN] and creatinine levels were measured in the blood. Moreover, glutathione [GSH], lipid peroxide expressed as thiobarbituric acid reactive substance [TBARS] levels, superoxide dismutase [SOD] and catalase [CAT] activities were determined in renal tissues. GM produced elevation in urinary total protein, BUN, serum creatinine and TBARS levels. On the other hand, GM reduced the GSH level and SOD, CAT activities. The simultaneous administration of GTE plus gentamicin protected kidney tissues against nephrotoxic effect of gentamicin as evidenced from amelioration of histopathological alterations and normalization of kidney biochemical parameters

Melatonin and N-acetyl cystein protect rats against carbon tetrachloride-induced acute liver damage

The present study was designed to investigate the protective effects of melatonin [MLT] and/or N-acetylcystein [NAC] against carbon tetrachloride [CCl4] induced liver cirrhosis in rats. Injection of CCl4 [2 ml/kg] to adult female wistar rats produced a significant elevations in alanine transaminase [ALT], aspartate transaminase [AST], serum and liver Malonaldehyde [MDA] and serum nitric oxide [NO]. The maximal percentages of increase were 517%, 237%, 48.1%, 86.64% and 28.31% respectively. On the other hand, there was a marked decrease in serum albumin, by -36.41% and liver contents of reduced glutathione [GSH] by -79.5% after CCl4 treatment. The pineal hormone MLT and NAC were tested for their protective activity when each given alone and in combination together in cirrhotic rats. MLT, NAC and their combinations were significantly decreased levels of serum ALT [-25.5%, -15.7% and -29% respectively], serum AST [-22% for NAC alone and -16% for MLT+NAC], serum MDA [-33%, -30.5% and -43% respectively], liver MDA [-58%, -37% and -67.6% respectively] and serum NO [-21.5%, -17.5% and -26% respectively]. On opposite direction, MLT, NAC and their combinations were significantly increased liver GSH contents by 62%, 35% and 258% respectively. These results suggest that oxidative process occur at the site of cell integrity and are involved in the damage effect of CCl4 and indicate that free radicals may be a major component of liver cirrhosis. Likewise, MLT, NAC and their combination presumably due to their antioxidant and free radicals scavenging activity is highly protective against the biochemical changes associated with CCl4 treatment