Effects of Graptopetalumparaguayense extract on tert‐ butylhydroperoxide‐induced oxidative stress

BACKGROUND: Graptopetalum paraguayense E. Walther is used in folk medicine to lower blood pressure, protect liver function and relieve pain and infection. The effect and mechanism of its 50% ethanolic extract (GE50) were investigated in tert‐butylhydroperoxide (t‐BHP)‐induced Wistar rats. The serum was analysed for aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities while the tissue cytosols were analysed for lipid peroxidation, antioxidant level and enzyme activities. RESULTS: The liver was the primary target organ while the heart appeared to be the least responsive organ for t‐BHP treatment among the three tissues investigated. t‐BHP treatment increased serum AST and ALT activities, which are indicators of liver toxicity, while GE50 pretreatment reduced t‐BHP‐induced liver damage. t‐BHP treatment induced lipid peroxidation in the liver and brain but not in the heart. GE50 pretreatment prevented t‐BHP‐induced lipid peroxidation by maintaining superoxide dismutase (SOD) activity as well as glutathione (GSH) and vitamin C levels in the liver and vitamin E level in the brain. Although t‐BHP treatment did not induce lipid peroxidation in the heart, it caused a decrease in antioxidant level. GE50 pretreatment prevented the t‐BHP‐induced decrease in vitamin C level in the heart. CONCLUSION: GE50 pretreatment in rats protects the liver and brain from possible damage by t‐BHP‐induced lipid peroxidation. Copyright © 2007 Society of Chemical Industry     

Activities of antioxidant enzymes in rats fed with hot-smoked rainbow trout (Oncorhynchus mykiss)

The activities of antioxidant enzymes in rats fed with hot‐smoked rainbow trout (Oncorhynchus mykiss) was investigated. Four diets containing fresh and hot‐smoked rainbow trout flesh and vitamin were prepared and commercial pellet food purchased. Four groups of rats were fed with the diets for 28 days. Body weight was checked weekly. No significant (P > 0.05) differences were found in weight between groups. Malondialdehyde (MDA) values of group B and group D were found to be significantly increased (P < 0.05). Differences in glutathione peroxidase (GPX) and glutathione reductase (GR) values were not significant (P > 0.05) between groups. The difference in superoxide dismutase (SOD) and catalase (CAT) values was found to be significant (P < 0.05). The hot smoked process led to significant changes as decreased in the antioxidant enzymes activities. Our results indicate that determination of MDA, GPX, GR, SOD and CAT parameters in blood may help to point out cancer risk in humans.     

Mechanism of preventive action of Viburnum dilatatum Thunb (gamazumi) crude extract on oxidative damage in rats subjected to stress

The fruit of Viburnum dilatatum Thunb (gamazumi) has been shown to prevent oxidative injury induced by water immersion restraint stress (WIRS) in rats. In this study the effect of gamazumi crude extract (GCE) on antioxidant enzymatic activities in the plasma, liver and stomach of rats with WIRS was investigated to elucidate the mechanism of prevention of oxidative injury. Ulcer formation and lipid peroxidation were inhibited in rats supplied GCE for 2 weeks in comparison with rats supplied water. Although the activities of plasma, hepatic and gastric antioxidant enzymes in rats given water were decreased by WIRS, only slight changes were observed in rats given GCE. There was no difference in enzymatic activities between the water and GCE groups not subjected to WIRS. Furthermore, ferrous ascorbate‐induced oxidation in hepatic homogenate from rats given GCE was inhibited. These results suggest that ingestion of GCE does not induce antioxidant enzymes and that the absorbed antioxidant components of GCE have a direct effect on oxidative injury in the body. Copyright © 2003 Society of Chemical Industry     

Ameliorative effect of Grewia tenax (Forssk) fiori fruit extract on CCl(4)-induced oxidative stress and hepatotoxicity in rats

The ethanol extract of Grewia tenax (GTE) fruit was tested for possible efficacy against carbon tetrachloride (CCl(4)) induced liver toxicity in Wistar albino rats. GTE at doses of 250 and 500 mg/kg were administered orally to CCl(4)-treated rats. Acute toxicity test and sleeping time determination were done with mice. The results showed that oral administration of GTE for 3 wk to rats significantly reduced the CCl(4)-induced elevated levels of serum glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, gamma-glutamyl transferase, alkaline phosphatase, bilirubin, cholesterol, high-density lipoproteins, low-density lipoproteins, very low density lipoproteins, and triglycerides. Moreover, it was found that the treatment with GTE significantly elevated the hemoglobin level in serum and increased the nonprotein sulfhydryl and total protein contents in the liver tissue, and a significant diminution was observed in the CCl(4)-induced elevated levels of malondialdehyde in the liver tissue. The biochemical findings were supported by an evaluation with liver histopathology. Pentobarbital-induced prolongation of narcolepsy in mice was shortened significantly by the extract. The observed hepatoprotective effect is believed to occur due to antioxidant properties of the contents of G. tenax extract, which may provide a new drug to be used for fighting liver diseases and it validates its folkloric use in anemic and other conditions.     

纹党多糖对四氧嘧啶诱导糖尿病大鼠血糖血脂的影响

研究纹党多糖(Codonopisis pilosula polysaccharide,CPP)对四氧嘧啶诱导糖尿病大鼠血糖和血脂的影响。以腹腔注射四氧嘧啶(ALX)构建大鼠糖尿病模型,将建模成功的大鼠随机分为糖尿病模型组、CPP高、中、低剂量处理组、阳性对照组(二甲双胍处理组、格列苯脲处理组和肾上腺素处理组),以生理盐水为空白对照组。连续灌胃给药28 d,研究CPP对糖尿病大鼠空腹血糖(FBG)、糖化血红蛋白(Hb Alc)、总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白(HDL)、低密度脂蛋白(LDL)等指标的影响。结果显示,CPP能明显降低正常大鼠血糖,能极显著(p<0.01)降低肾上腺素引起的高血糖,能够有效降低糖尿病大鼠的FBG、Hb Alc、TC、TG,升高HDL含量。纹党多糖能够显著降低糖尿病大鼠血糖并显著改善糖尿病大鼠血脂代谢紊乱。      

番茄皂苷A粗提物对动脉粥样硬化大鼠血脂和肝脏的影响

目的:研究番茄皂苷A粗提物(CEEA)对高脂诱导动脉粥样硬化(AS)大鼠血脂和肝脏的影响。方法:采用高脂饲料喂饲和腹腔注射维生素D3建立大鼠AS模型。72只雄性健康SD大鼠随机分为正常组、AS模型组、CEEA低剂量组、CEEA中剂量组、CEEA高剂量组、辛伐他汀组。24周后处死大鼠,测量各组大鼠生理生化指标。结果:与AS模型组相比,CEEA给药组能明显降低血清总胆固醇、甘油三酯、低密度脂蛋白胆固醇含量,明显升高高密度脂蛋白胆固醇水平,明显降低动脉硬化指数;明显降低肝脏指数、肝脏总胆固醇、甘油三酯、丙二醛水平,明显升高超氧化物歧化酶水平。结论:CEEA能有效调节AS大鼠血脂代谢,降低脂质在肝脏中积聚,提高肝脏的抗氧化能力,有保护肝脏的作用。     

The effects of dietary fish oil on inflammation, fibrosis and oxidative stress associated with obstructive renal injury in rats

Scope: We examined whether dietary supplementation with fish oil modulates inflammation, fibrosis and oxidative stress following obstructive renal injury. Methods and results: Three groups of Sprague–Dawley rats (n=16 per group) were fed for 4 wk on normal rat chow (oleic acid), chow containing fish oil (33 g eicosapentaenoic acid and 26 g docosahexaenoic acid per kg diet), or chow containing safflower oil (60 g linoleic acid per kg diet). All diets contained 7% fat. After 4 wk, the rats were further subdivided into four smaller groups (n=4 per group). Unilateral ureteral obstruction was induced in three groups (for 4, 7 and 14 days). The fourth group for each diet did not undergo surgery, and was sacrificed as controls at 14 days. When rats were sacrificed, plasma and portions of the kidneys were removed and frozen; other portions of kidney tissue were fixed and prepared for histology. Compared with normal chow and safflower oil, fish oil attenuated collagen deposition, macrophage infiltration, TGF‐β expression, apoptosis, and tissue levels of arachidonic acid, MIP‐1α, IL‐1β, MCP‐1 and leukotriene B₄. Compared with normal chow, fish oil increased the expression of HO‐1 protein in kidney tissue. Conclusions: Fish oil intake reduced inflammation, fibrosis and oxidative stress following obstructive renal injury.