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

Antidiabetic effect of portulaca oleracea extract, alone and plus gliclazide, on streptozotocin-nicotinamide-induced type 2 diabetes in rats

Type 2 diabetes is rapidly emerging as a pandemic. To identify an alternative or adjunctive approach to existing medications, the antidiabetic effect of Portulaca oleracea extract [PE], alone and plus gliclazide [Gl], was investigated on streptozotocin [STZ]-nicotinamide-induced type 2 diabetes in rats. Oral administration of the PE, alone and plus Gl, to diabetic rats for 15 and 30 days resulted in a significant decrease in the level of blood glucose, with a concomitant increase in serum insulin level as compared to untreated diabetic rats. The antidiabetic activity was observed to be time-dependent and was most effective in a combined treatment of PE with a reduced dose of Gl. In addition, enzymatic antioxidant superoxide dismutase [SOD] and nonenzymatic antioxidants: reduced glutathione [GSH] and vitamin-C were significantly increased after the same periods of treatment except vitamin-C which significantly increased only after 30 days. In conclusion, in type 2 diabetic rats PE shows an antidiabetic action which may be mediated, at least in part, by compensating for defective insulin release and enhancing antioxidant status. The combined therapy of PE plus Gl has better antidiabetic activity than PE individual therapy. Therefore, Portulaca oleracea can be recommended as an adjunctive support for therapy of type 2 diabetes