Green tea polyphenols protect spinal cord neurons against hydrogen peroxide-induced oxidative stress

Green tea polyphenols are strong antioxidants and can reduce free radical damage. To investigate their neuroprotective potential, we induced oxidative damage in spinal cord neurons using hydrogen peroxide, and applied different concentrations(50–200 μg/mL) of green tea polyphenol to the cell medium for 24 hours. Measurements of superoxide dismutase activity, malondialdehyde content, and expression of apoptosis-related genes and proteins revealed that green tea polyphenol effectively alleviated oxidative stress. Our results indicate that green tea polyphenols play a protective role in spinal cord neurons under oxidative stress.     

Montelukast modifies simvastatin-induced myopathy and hepatotoxicity

Montelukast (MNK) has prominent anti-inflammatory and antioxidant activities. It can protect the liver in different hepatotoxic models in animals. Simvastatin (SMV) is one of commonly used lipid lowering drugs for treatment of dyslipidemia in order to reduce cardiovascular disease. It has severe side effects such as myopathy and hepatotoxicity. The aim of the present study is to investigate the possible effect of MNK on SMV-induced myopathy and hepatotoxicity. Four groups of male rats: control group which received saline via stomach tube, MNK treated group (received 10 mg/kg/day MNK via stomach tube), SMV treated group (received 30 mg/kg/day SMV via stomach tube), and MNK + SMV (combination) group which received both MNK and SMV. All animals were treated for 14 days before obtaining blood and tissue samples. SMV has both hepatotoxic effects and myopathy. SMV caused a significant increase in myoglobin, creatinine kinase, ALT, AST, ALP, and bilirubin but, it decreased total proteins, globulin and albumin levels. Co-treatment of SMV and MNK increased the antioxidant activity significantly. MNK modifies partially the myopathic changes and hepatotoxic effect of SMV. Co-administration of MNK and SMV decreased their toxic potentials on the liver, skeletal muscles, and kidney. They have antioxidant activities when given together that produce muscle and hepatic protective effects.     

Chemoprevention of liver cancer by plant polyphenols

Primary liver cancer or hepatocellular carcinoma (HCC) is one of the most frequent tumors representing the fifth commonest malignancy worldwide and the third cause of mortality from cancer. Currently, the treatments for HCC are not so effective and new strategies are needed for its fight. Chemoprevention, the use of natural or synthetic chemical agents to reverse, suppress or prevent carcinogenesis is considered an important way for confronting HCC. Many of the chemopreventive agents are phytochemicals, namely non-nutritive plant chemicals with protective or disease preventive properties. In this review, we focus on plant polyphenols, one of the most important classes of phytochemicals, their chemopreventive properties against HCC and discuss the molecular mechanisms accounting for this activity.     

Comparison of protective and curative potential of Daucus carota root extract on renal ischemia reperfusion injury in rats

Abstract

Context: Daucus carota Linn (Apiaceae), a useful vegetable, is traditionally used in treating kidney and hepatic dysfunctions.

Objective: To evaluate the protective and curative potential of D. carota root extract on renal ischemia reperfusion injury in rats.

Materials and methods: Wistar rats were selected with 8?+?8 groups (n?=?6). Renal pedicles of rats were occluded for 45?min and allowed for reperfusion period. In protective and curative studies, 14 days prior and 14 days after the induction of ischemia/reperfusion (I/R), rats received petroleum ether extract (PEE 250 and 500?mg/kg), fractional methanol extract (FME 250 and 500?mg/kg) and direct methanol extract (DME 250 and 500?mg/kg) of Daucus carota root, orally, once daily.

Results: PEE at a dose of 500?mg/kg significantly (p?<?0.001) reduced the levels of serum creatinine (0.853–3.090?mg/dl), uric acid (1.300–3.500?mg/dl) and urea (58.26–132.00?mg/dl) compared to disease control. FME at a dose of 500?mg/kg body weight significantly (p?<?0.001) reduced the levels of serum creatinine (0.960–3.090?mg/dl), uric acid (1.700–3.500?mg/dl) and urea (77.17–132.00?mg/dl) compared to disease control. DME at a dose of 500?mg/kg body weight significantly (p?<?0.001) reduced the levels of serum creatinine (1.173–3.090?mg/dl), uric acid (2.267–3.500?mg/dl) and urea (84.75–132.00?mg/dl) compared to disease control.

Discussion and conclusion: Findings demonstrate that postconditioning with the D. carota root extract significantly improves kidney function in I/R rats.     

管花肉苁蓉麦角甾苷对衰老小鼠端粒酶活性和免疫功能的影响

目的观察管花肉苁蓉麦角甾苷(CTWA)对实验性衰老小鼠心、肝和脑组织中丙二醛(MDA)含量、端粒酶活性和免疫功能的影响。方法小鼠sc 10%D-半乳糖10mL·kg-1,每天1次,连续8周,建立亚急性衰老模型。给药组小鼠从造模第9周起,分别ig给予CTWA 10,20和40mg·kg-1,每天1次,连续2周。硫代巴比妥酸比色法检测MDA含量;PCR-ELISA法检测端粒酶活性;[3H]TdR掺入法测定淋巴细胞增殖反应;中性红实验测定小鼠腹腔巨噬细胞吞噬功能;放射免疫法测定外周血白细胞介素2(IL-2)含量。结果模型组小鼠心、肝和脑MDA含量明显增加,心和肝端粒酶活性明显降低,淋巴细胞增殖反应、腹腔巨噬细胞吞噬功能和外周血IL-2含量均显著下降。给予CTWA 2周,小鼠心、肝和脑MDA含量明显降低,CTWA 40mg·kg-1组小鼠心和脑组织端粒酶活性明显升高,淋巴细胞增殖反应、腹腔巨噬细胞吞噬功能和外周血IL-2含量明显升高。结论CTWA能拮抗自由基损伤,增强衰老小鼠心和脑组织端粒酶活性和机体免疫功能,这些可能与CTWA的抗衰老作用有关。     

硫化氢对大鼠内毒素性急性肺损伤的影响

目的观察硫化氢(H2S)对脂多糖(LPS)所致大鼠内毒素性急性肺损伤(ALI)的影响,探讨其对肺脏的作用机制。方法♂SD大鼠共64只,随机分为8组,每组8只:Ⅰ:3h空白对照组;Ⅱ:LPS3h组;Ⅲ:6h空白对照组;Ⅳ:LPS6h组;Ⅴ:LPS+NaHS低剂量组;Ⅵ:LPS+NaHS中剂量组;Ⅶ:LPS+NaHS高剂量组;Ⅷ:LPS+PPG组。LPS3h和LPS6h组给予LPS,其相应空白对照组给予生理盐水,分别在3h或6h时处死大鼠;LPS+NaHS低、中、高剂量组和LPS+PPG组分别在给LPS3h时腹腔注射低、中、高剂量氢硫化钠(NaHS)或炔丙基甘氨酸(PPG),再观察3h后处死大鼠。光、电镜下观察肺组织形态学改变,检测肺系数、肺湿/干重比(W/D)、血浆中H2S含量、肺组织胱硫醚-γ-裂解酶(CSE)活性,以及肺组织中丙二醛(MDA)含量、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性的变化。结果LPS3h和LPS6h组与相应的空白对照组比较,光、电镜下肺组织明显受损,超微结构明显改变,肺系数、肺湿/干重比和肺组织MDA含量升高,血浆中H2S的含量、肺组织CSE以及SOD、GSH-Px活性降低。LPS+NaHS低、中、高剂量组与LPS6h组比较,光、电镜下肺组织受损情况均有不同程度改善,肺系数、肺湿/干重比和肺组织MDA含量降低,血浆H2S含量、肺组织CSE以及SOD、GSH-Px活性升高。LPS+PPG组与LPS6h组比较,光、电镜下肺组织损伤无改善,肺系数、肺湿/干重比和肺组织MDA含量升高,血浆中H2S的含量、肺组织CSE和SOD活性降低,肺组织GSH-Px活性无明显变化。结论CSE/H2S体系可能参与内毒素性ALI的病理生理过程,外源性补充H2S可减轻内毒素性ALI。     

卡维地洛对顺铂致大鼠急性肾衰竭的预防作用

目的观察卡维地洛对顺铂致大鼠急性肾衰竭的影响,并初步探讨其作用机制。方法Wistar大鼠给予卡维地洛5,15和30mg.kg-1,ig,每日1次,连续6d,于d3单次ip顺铂10mg.kg-1。于d6测定血清尿素氮(BUN)和肌酐(SCr)含量,尿N-乙酰-β-D-氨基葡萄糖苷酶(NAG)活性,肾组织丙二醛(MDA)含量、超氧化物歧化酶(SOD)及谷胱甘肽过氧化物酶(GSH-Px)活性;苏木素-伊红染色观察肾脏病理改变。结果顺铂组大鼠血清BUN和SCr含量升高,尿NAG活性升高,肾组织MDA水平增加,SOD和GSH-Px水平降低,肾脏病理改变明显。预先给予卡维地洛5和15mg.kg-1可明显逆转上述改变,但加大剂量至30mg.kg-1时效应反而降低。结论在一定剂量范围内,卡维地洛可能通过减少活性氧产生,增加抗氧化酶活性而减轻顺铂所致急性肾衰竭。     

Protective effects of Passiflora alata extract pretreatment on carbon tetrachloride induced oxidative damage in rats.

The leaf extract of Passiflora alata Dryander (P. alata) has been demonstrated to possess antioxidant activity in vitro. The aim of this study was to investigate the effects of P. alata leaf extract pretreatment on carbon tetrachloride-treated rats. Male Wistar rats were randomly allocated into four groups: group 1 (control - vehicle), group 2 and 3 (P. alata extract - 1 and 5mg/kg, respectively) and group 4 (trolox - 0.18mg/kg). Rats received daily pretreatment by oral gavage for 30 days followed by a single dose of CCl(4) (3ml/kg i.p. in vegetable oil) on the 30th day and were killed after 6h. The pretreatment with the P. alata extract provided significant protection to liver, evidenced by lower degree of necrosis, decreased lipid peroxidation (TBARS) and higher catalase and superoxide dismutase activities. Additionally, pretreated-rats with P. alata (5mg/kg) showed significantly decreased cardiac TBARS levels. Our results indicate that a low oral dose of P. alata leaf extract has both hepato and cardioprotective effects on rats treated with CCl(4).