血红素加氧酶1对实验性肝硬化内毒素血症大鼠肝功能的影响

目的 探讨血红素加氧酶1(HO-1)在实验性肝硬化内毒素血症大鼠中的作用.方法 80只大鼠均分为4组:对照组为正常大鼠+脂多糖(LPS);其余3组用硫代乙酰胺(TAA)诱导大鼠肝硬化模型后,TAA组腹腔内注射生理盐水,TAA+LPS组注射LPS,HM组注射氯化高铁血红素+LPS.造模后检测AST和ALT.结果 与对照组比较,其余3组血浆中ALT和AST水平均明显升高(P＜0.05),且HM组＞TAA+ LPS组＞TAA组.结论 HO-1通过其氧化损伤和促纤维化,促进大鼠肝硬化内毒素血症时肝损害.     

二氧化碳气腹对大鼠肝脏造成的缺血再灌注损伤及异丙酚促进HO-1表达的保护作用

目的探讨实验室二氧化碳(CO_2)模拟腹腔镜高气腹压力对大鼠肝脏造成的缺血再灌注损伤以及异丙酚的保护作用和机制。方法选用280~320 g的Wistar成年雄性大鼠,实验前各组大鼠禁食12 h,可自由饮水。选取雄性大鼠48只,随机分成4组,每组12只:对照组(A组)、缺血组(B组)、再灌注组(C组)、异丙酚组(D组),观察各组天冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)、超氧化物歧化酶(SOD)、丙二醛(MDA)以及血红素氧合酶1(HO-1)表达的变化。结果 B组、C组与A组比较,MDA逐渐增高,而SOD逐渐降低,HO-1表达反应性逐渐增加,HE染色和免疫组化提示损伤逐渐加重;D组与B组、C组比较,MDA指标明显降低,SOD明显增高,HO-1表达继续增加,HE染色和免疫组化可见损伤明显减轻。结论 CO2气腹可以造成大鼠肝脏缺血再灌注损伤;缺血和再灌注是不同的损伤过程,即:缺血状态解除后,对大鼠肝脏损伤并未停止,反而由于再灌注过程而进一步加重;异丙酚可通过促进HO-1的表达机制而发挥其保护性作用。     

胰岛素抵抗状态下血红素氧合酶-1/一氧化碳与一氧化氮合酶/一氧化氮相互调节的研究

目的探讨胰岛素抵抗状态下血红素氧合酶-1（HO-1）／一氧化碳（CO）与一氧化氮合酶（NOS）／一氧化氮（NO）的相互调节关系。方法通过6周高脂饮食成功复制胰岛素抵抗SD大鼠模型44只，分为胰岛素抵抗组26只，正铁血红素组10只，锌原卟啉组8只；分别腹腔注射生理盐水、正铁血红素、锌原卟啉。12只经6周普通饲料喂养的SD大鼠为对照组，给予腹腔注射生理盐水。检测血CO含量以及胸主动脉组织的NO、诱导型NOS（iNOS）、内皮型NOS（eNOS）的水平，RT-PCR检测主动脉iNOS、eNOS mRNA的表达。结果正铁血红素提高胰岛素抵抗大鼠主动脉组织eNOS活性及其mRNA表达，降低iNOS活性及其mRNA表达。降低血清及动脉组织的NO水平。增加动脉血CO水平。结论HO-1通过对NOS／NO信息通道的调节。抑制iNOS的活性，从而使应激状态下NO水平下降。发挥HO-1的血管保护作用。     

地骨皮醇提物对糖尿病模型大鼠的保护作用

目的:研究地骨皮醇提物对糖尿病模型大鼠的保护作用。方法:高脂饲料喂养4周后腹腔注射链脲佐菌素以复制大鼠糖尿病模型。50只SD大鼠随机均分为正常对照(等容生理盐水)组、模型(等容生理盐水)组与地骨皮醇提物高、中、低剂量(40、20、10 g/kg)组,灌胃给药,每天1次,连续4周。测定超氧化物歧化酶(SOD)、丙二醛(MDA)、丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、一氧化氮(NO)水平,观察大鼠主动脉血管形态学,实时荧光定量聚合酶链反应(RT-PCR)法测定诱导型一氧化氮合酶(iNOS)、内皮型一氧化氮合酶(eNOS)mRNA的表达。结果:与正常对照组比较,模型组大鼠SOD活性减弱,NO含量减少,MDA含量增加,ALT、AST活性增强,eNOS mRNA表达减弱,iNOS mRNA表达增强,差异有统计学意义(P<0.01);大鼠主动脉血管形态学呈病理状态。与模型组比较,地骨皮醇提物高、中剂量组大鼠SOD活性增强,NO含量增加,MDA含量减少,ALT、AST活性减弱,iNOS mRNA表达减弱,eNOS mRNA表达增强,差异有统计学意义(P<0.01或P<0.05);大鼠主动脉血管形态学病理状态得到一定改善。结论:地骨皮醇提物对糖尿病模型大鼠有一定保护作用。     

诱导血红素加氧酶-1对肝硬化大鼠肠黏膜屏障的保护作用

目的 探讨血红素加氧酶-1(HO-1)对肝硬化大鼠肠黏膜屏障的保护作用.方法 建立四氯化碳(CCl4)致大鼠肝硬化动物模型,钴原卟啉诱导HO-1表达.FITC-荧光标记法检测大鼠肠黏膜通透性.ELISA法检测血浆TNF-α及IL-6含量.分光光度法检测肠组织HO活性及MDA含量.TUNEL染色法检测肠黏膜细胞凋亡.Western blot检测肠组织Bcl-2蛋白表达.结果 与control组比较,肝硬化(HC)组大鼠肠道通透性显著增高(P＜0.01);HC+HO组大鼠肠道通透性比HC组显著降低(P＜0.05).血浆TNF-α水平在HC组显著高于control组(P＜0.01),而在HC+HO组显著低于HC组(P＜0.05);IL-6水平在HC组显著高于control组(P＜0.01).肠组织匀浆MDA含量在HC组显著高于control组(P＜0.01),而在HC+HO组显著低于HC组(P＜0.01).诱导HO-1可有效抑制肝硬化大鼠肠黏膜细胞凋亡.HC组大鼠Bcl-2蛋白表达量显著低于control组(P＜0.01),诱导HO-1可使Bcl-2蛋白表达量显著高于control组(P＜0.01).结论 诱导HO-1可能通过抑制炎症与细胞凋亡保护肝硬化大鼠肠黏膜屏障.     

血红素氧合酶在肝硬化大鼠肾脏中的表达

目的探讨血红素氧合酶(HO)在肝硬化大鼠肾脏中的表达情况。方法将20只雄性SD大鼠随机分为肝硬化组和正常对照组各10只,肝硬化组大鼠胸、腹部交替皮下注射40%四氯化碳建立肝硬化模型;正常对照组给予单纯注射精制油,饮用灭菌水。采用Western Blotting法测定、比较2组大鼠HO-1蛋白的表达情况。结果通过对Western印迹结果进行定量分析,从杂交的信号强度可知,肝硬化组大鼠与正常对照组相比,肾脏HO-1表达降低至53.4%。结论 HO-CO系统参与了肝硬化时肾脏血流动力学紊乱的形成。     

谷氨酰胺对内毒素诱导大鼠肺组织氧化应激反应的影响

目的探讨谷氨酰胺对内毒素(LPS)诱导大鼠肺组织氧化应激反应的影响。方法雄性SD大鼠50只,随机分为5组(n=10):对照组(A组);LPS组(B组),股静脉注射LPS 5 mg/kg;C、D、E组为谷氨酰胺+LPS组,分别于LPS注入前1 h时,LPS注入同时,LPS注入后1 h时,均静脉注射谷氨酰胺0.75 g/kg。于注射LPS后4 h时处死大鼠,测定肺组织超氧化物歧化酶(SOD)活性、丙二醛(MDA)、一氧化氮(NO)、总一氧化氮合酶(tNOS)水平,诱导型一氧化氮合酶(iNOS)活性及iNOS mRNA表达。结果与A组比较,B组肺组织SOD活性下降,MDA、NO、tNOS水平、iNOS活性及iNOS mRNA表达均升高(P<0.05及P<0.01);与B组比较,C、D组肺组织SOD活性升高,MDA、NO、tNOS水平、iNOS活性及iNOS mRNA表达降低(P<0.05及P<0.01),E组上述各项指标比较差异无统计学意义(P>0.05)。结论谷氨酰胺早期给药可减轻LPS诱导肺组织氧化应激反应。     

锌原卟啉与血红素对弥漫性脑外伤大鼠耳蜗血红素加氧酶表达及听性脑干反应影响的实验研究

目的 探讨锌原卟啉(Znpp)与血红素(Heme)对弥漫性脑外伤大鼠耳蜗血红素加氧酶(HO-1)表达及听性脑干反应(ABR)的影响.方法 建立弥漫性脑外伤大鼠模型并随机分组,采用ABR测定、光镜、免疫组织化学等方法,观察各组动物耳蜗HO-1表达及ABR的变化.结果 外伤后各组ABR阈值及各波潜伏期差异均有统计学意义(均P＜0.05).对照组大鼠耳蜗HO-1无表达,外伤后各组耳蜗HO-1表达有明显变化(P＜0.01).正常对照组与DBI组、Znpp、Heme各组灰度值差异均有统计学意义(均P＜0.05).结论 锌原卟啉与血红素对弥漫性脑外伤大鼠耳蜗HO-1表达及ABR均有不同程度的影响,血红素对听功能的保护作用可能与HO-1表达升高有关.     

孕酮对幼年大鼠感染性脑水肿水通道蛋白4表达的影响

目的 观察内毒素(LPS)致幼年大鼠感染性脑水肿后,腹腔注射孕酮(Prog)对水通道蛋白4(AQP4)表达的影响.方法 将90只幼年大鼠随机分为对照组(C,n=10),内毒素组(LPS,n=40)和内毒素+孕酮组(LPS+Prog,n=40).建立LPS致大鼠感染性脑水肿模型后1 h,LPS+Prog组和LPS组分别腹腔注射孕酮和生理盐水,以后每6小时注射一次.手术后6、12、24和48 h处死动物,分别行脑组织含水量的测定,用免疫组化和RT-PCR检测脑组织内AQP4表达水平.结果 LPS组脑组织含水量明显高于C组和LPS+Prog组(P<0.01).在LPS注射6 h时,幼鼠脑组织 AQP4表达明显增加,12 h达高峰.LPS+Prog组在LPS注射后12 h时,脑组织中AQP4在蛋白水平和mRNA水平的表达均低于LPS组(P<0.01).结论 孕酮可能在转录和翻译水平下调AQP4的表达,从而抑制LPS诱导的幼年大鼠感染性脑水肿的发生发展.     

巴曲酶对缺血性眩晕大鼠及其脑组织Nrf2/HO-1信号通路的影响

目的探讨巴曲酶对缺血性眩晕大鼠眩晕症状、抗氧化指标、炎症因子、血液流变学指标及脑组织NF-E2-相关因子2/血红素氧合酶1(Nrf2/HO-1)信号通路的影响。方法 40只SD大鼠随机分为假手术组、模型组、巴曲酶组(尾iv 1 BU/kg)、NRF2抑制剂(ML385)组(ip 30 mg/kg)、巴曲酶+ML385组(尾iv 1 BU/kg巴曲酶后ip 30 mg/kg ML385),每组8只,除假手术组外,其余各组大鼠均通过结扎右侧颈动脉及右侧锁骨下动脉构建缺血性眩晕大鼠模型,造模成功后按照各组给药方式进行给药处理,持续1周。全自动血液流变分析仪检测各组大鼠血液流变学指标,眩晕实验测定各组大鼠眩晕症状的变化程度;苏木精-伊红染色(HE)检测大鼠脑组织病理变化;酶联免疫吸附(ELISA)试剂盒检测大鼠血清一氧化氮(NO)、内毒素(ET),脑组织肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、超氧化物歧化酶(SOD)、丙二醛(MDA)水平;蛋白免疫印迹(WB)法检测大鼠脑组织中Nrf2/HO-1通路蛋白表达。结果与假手术组相比,模型组大鼠跳台逃避潜伏期显著延长,眩晕症状、脑组织神经细胞受损严重,血液流变学指标,血清NO和ET水平,脑组织中TNF-α、IL-1β、MDA水平显著升高,SOD水平及Nrf2、HO-1蛋白表达显著降低。与模型组相比,巴曲酶组大鼠眩晕症状、脑组织神经细胞受损得到缓解,血液流变学指标、血清NO和ET水平、脑组织中TNF-α、IL-1β、MDA水平显著降低,脑组织SOD水平及Nrf2、HO-1蛋白表达显著升高;ML385组大鼠眩晕症状及各项指标与模型组变化趋势相似且更严重;与巴曲酶组相比,巴曲酶+ML385组大鼠眩晕症状、脑组织神经细胞受损严重,血液流变学指标,血清NO和ET水平,脑组织中TNF-α、IL-1β、MDA水平显著升高,SOD水平及Nrf2、HO-1蛋白表达显著降低。结论巴曲酶可能通过改善血液流变学、提高抗氧化能力、抑制炎症因子分泌及启动Nrf2/HO-1通路发挥对缺血性眩晕的保护作用。     

Differential induction of heme oxygenase-1 in macrophages and hepatocytes during acetaminophen-induced hepatotoxicity in the rat: effects of hemin and biliverdin

Heme oxygenase-1 (HO-1), also known as heat shock protein 32, has been shown to protect against oxidant-induced tissue injury. In the present studies, we analyzed expression of this enzyme in macrophages and hepatocytes following acetaminophen administration and its potential role in hepatotoxicity. Treatment of rats with a hepatotoxic dose of acetaminophen (1 g/kg, ip) resulted in a time-dependent induction of HO-1 in the liver. This was observed within 6 h of acetaminophen administration in both hepatocytes and macrophages. Hepatocytes were found to be more sensitive than macrophages to the effects of acetaminophen on HO-1. Up regulation of HO-1 in the liver following acetaminophen administration correlated with induction of ferritin and manganese superoxide dismutase (MnSOD). To determine if HO-1 was hepatoprotective, rats were pretreated with hemin (30 micromol/kg, ip), a potent inducer of the enzyme. Following hemin treatment, we observed a time-dependent increase in HO-1 protein in the liver and in serum bilirubin levels. Pretreatment of rats with hemin was found to prevent acetaminophen-induced hepatotoxicity, as measured histologically and biochemically by decreased serum transaminase levels. This was correlated with more rapid increases in expression of hepatic ferritin and MnSOD. Heme metabolism via HO-1 generates biliverdin, which is rapidly converted to bilirubin by biliverdin reductase. Pretreatment of rats with biliverdin (40 micromol/kg, ip) was also found to block acetaminophen-induced injury. These data suggest that HO-1 is an important component of antioxidant defense during acetaminophen-induced hepatotoxicity.     

藏药三果汤调节Nrf2/HO-1信号通路干预高脂血症大鼠的作用机制研究

目的：基于Nrf2/HO-1信号通路探讨藏药三果汤对高脂血症大鼠保护作用及相关作用机制。方法：雄性SD大鼠48只,随机分为6组,即正常对照组、模型对照组、辛伐他汀组（3.5 mg/kg）,藏药三果汤低、中、高剂量组（0.43 g/kg、0.86 g/kg、1.72 g/kg）,每组8只。正常组给予基础饲料喂养,其余各组给予H00016高脂饲料喂养,制备高脂血症大鼠模型,造模的同时,各给药组每天一次给予相应药物灌胃,正常对照组、模型对照组给予等体积的生理盐水（1次/d）,连续灌胃6周。实验期间每周固定时间称取各组大鼠体重一次,6周后试剂盒检测血清中血脂（TC、TG、LDL与HDL）及氧化指标（MAD、SOD与GSH）的水平。Western Blot法测定肝组织中Nrf2、HO-1、Keap1、NQO1蛋白表达,采用person相关性分析分析血脂与氧化指标之间的相关性。结果：与正常对照组比较,模型对照组的体重明显增加,血清中的TC、TG、LDL、MDA含量明显升高,而血清中HDL含量明显减低,SOD、GSH活力明显减低（P<0.05或P<0.01）;与模型对照组比较,各给药组的体重减轻,血清中的TC、TG、LDL、MDA含量明显减低,血清中的HDL含量明显升高,SOD、GSH活力明显升高（P<0.05或P<0.01）。与空白对照组比较,模型对照组Keap1蛋白水平表达明显上调,Nrf2、HO-1与NQO1蛋白水平表达明显下调（P<0.05或P<0.01）,与模型对照组比较,三果汤低、高剂量肝组织中的Keap1蛋白水平表达明显下调,Nrf2、HO-1与NQO1蛋白水平表达明显上调（P<0.05或P<0.01）。相关性分析可见TG与SOD、HO-1及NQO1呈负相关,与Keap1呈正相关,TC与SOD、HO-1、GSH及Nrf2呈负相关,与Keap1及MDA呈正相关。结论：藏药三果汤可改善高脂血症大鼠体重及血脂水平,其机制可能与调节Nrf2/HO-1信号通路,改善氧化应激有关。     

Upregulation of heme oxygenase-1 with hemin prevents D-galactosamine and lipopolysaccharide-induced acute hepatic injury in rats

Heme oxygenase-1 (HO-1), the rate-limiting enzyme in heme catabolism, has been shown to be induced during oxidative injury, and its induction acts as an important cellular defense mechanism against such injuries. In this study, we examined the functional roles of HO-1 induction in a rat model of d-galactosamine (GalN) and lipopolysaccharide (LPS)-induced liver injury. We found that GalN/LPS treatment of rats produced severe hepatic injury, whereas upregulation of HO-1 by hemin pretreatment prevented rats from liver damage, as evidenced by decreased serum ALT, AST levels and ameliorated histological signs in the liver. Induction of HO-1 resulted in a significant decrease in hepatic malondialdehyde (MDA) contents, tumor necrosis factor-alpha (TNF-alpha) levels, iNOS/NO production, as well as the levels of caspase-3. In contrast, inhibition of HO activity by zinc protoporphyrin-9 (ZnPP, a specific inhibitor of HO) completely reversed HO-1-induced hepatoprotective effect. These data therefore suggested that HO-1 induction provided critical protection against GalN/LPS-induced liver injury, and the protection seemed to be mediated through the anti-oxidant, anti-inflammatory and anti-apoptotic functions.     

Tissue-specific gene expression of heme oxygenase-1 (HO-1) and non-specific delta-aminolevulinate synthase (ALAS-N) in a rat model of septic multiple organ dysfunction syndrome

Reactive oxygen species are thought to be involved in the pathogenesis of septic multiple organ dysfunction syndrome (MODS). It has been reported that heme oxygenase-1 (HO-1) (EC 1.14.99.3) is induced in septic animal models and is thought to confer protection against oxidative tissue injury. In this study, we examined changes in gene expression of HO-1 and non-specific delta-aminolevulinate synthase (ALAS-N) (EC 2.3.1.37), the rate-limiting enzymes in heme catabolism and heme synthesis, respectively, after intraperitoneal administration of bacterial lipopolysaccharide (LPS) to rats. LPS treatment caused the elevation of body temperature, increases in white blood cell counts, and marked elevation of serum interleukin-6 levels associated with liver, lung, and kidney injuries, characteristic of septic MODS. LPS administration significantly induced HO-1 mRNA, protein, and enzyme activity in the liver, lung, and kidney. In contrast, ALAS-N mRNA was decreased rapidly in the liver, followed by an oscillating recovery pattern. Induction of hepatic HO-1 mRNA and rapid suppression of ALAS-N mRNA were likely the result of a rapid increase in hepatic free heme concentration as judged by the increase in heme saturation of tryptophan pyrrolase. In contrast to that in the liver, the ALAS-N mRNA level in the lung and kidney was increased significantly after LPS administration, suggesting a novel mechanism of ALAS-N regulation in these tissues. These findings suggest that HO-1 and ALAS-N mRNA are regulated in a tissue-specific manner in a rat model of septic MODS.     

Hepatic mitochondrial prooxidant and antioxidant status in ethanol-induced liver injury in rats

In this study, prooxidant and antioxidant status in liver homogenates and their mitochondrial fractions were investigated in both chronic and chronic plus acute ethanol-treated rats. Increases in serum transaminase activities, as well as increases in total lipid, triglyceride, malondialdehyde (MDA) and diene conjugate (DC) levels and decreases in glutathione (GSH), vitamin E and vitamin C levels, have been observed in liver homogenates following chronic ethanol treatment (20% ethanol, v/v as drinking water for 3 months), but CuZn-superoxide dismutase (CuZnSOD), glutathione peroxidase (GSH-Px) and glutathione transferase (GST) activities remained unchanged in postmitochondrial fractions. When an acute dose of ethanol (5 g/kg, i.p.) was given rats which had received ethanol chronically, serum transaminase activities and hepatic lipid and MDA and DC levels increased further, but GSH levels and antioxidant enzymes decreased more compared to the chronic ethanol-treated rats. There were no significant differences in the levels of MDA, DC and protein carbonyl and the activities of GSH-Px and GST in the hepatic mitochondrial fraction of rats following both chronic and chronic plus acute treatments. Mn-superoxide dismutase (MnSOD) activities increased in both groups, but mitochondrial GSH levels decreased only after chronic plus acute treatment. Therefore, we suggest that the increase in MnSOD activity may play an important role in the regulation of mitochondrial susceptibility against ethanol-induced oxidative stress.     

基于Keap1-Nrf2/ARE信号通路研究牛磺酸对胰岛素抵抗模型大鼠氧化应激的影响

目的 通过研究牛磺酸对胰岛素抵抗大鼠模型的血糖、血脂、氧化应激指标以及Keap1-Nrf2/ARE信号通路重要靶点的影响,并探讨其分子调控机制。方法 建立胰岛素抵抗SD大鼠模型,测定连续灌胃给药7周后正常组、模型组、二甲双胍组、牛磺酸高剂量组以及牛磺酸低剂量组的空腹血糖（fasting blood glucose,FBG）、空腹胰岛素、甘油三酯（triglyceride,TG）、总胆固醇（total cholesterol,TC）、高密度脂蛋白、低密度脂蛋白,计算胰岛素抵抗指数;采用酶联免疫吸附试验法测定肝组织中超氧化物歧化酶（superoxide dismutase,SOD）、丙二醛（malondialdehyde,MDA）,运用RT-PCR技术检测肝组织中Nrf2、Keap1、HO-1、NQO1 mRNA的表达量。结果 给药7周后,与模型组比,牛磺酸高剂量组胰岛素抵抗大鼠FBG、空腹胰岛素降低（P<0.05）,血清TC、TG水平也降低（P<0.05）;大鼠肝组织的SOD升高、MDA降低（P<0.05）;肝组织中HO-1、NQO1、Nrf2的mRNA水平上调（P<0.05）, Keap1 mRNA水平下调（P<0.01）。结论 牛磺酸可调节糖尿病大鼠的血糖、血脂,改善模型大鼠氧化应激状态,减轻胰岛素抵抗,可能与其调控Keap1-Nrf2/ARE信号通路中关键基因表达从而改善氧化应激有关。     

Metabolic Activation of PCBs to Carcinogens in Vivo - A Review

Our earlier studies have shown that extracts derived from potato peel (PPE) are rich in polyphenols and possess strong antioxidant activity both in vitro and in vivo. The objective of the present study was to investigate its potential to offer protection against acute liver injury in rats. Rats pretreated with PPE (oral, 100mg/kgb.w./day for 7 days) were administered a single oral dose carbon tetrachloride (CCl(4), 3ml/kg b.w., 1:1 in groundnut oil) and sacrificed 8h of post-treatment. Hepatic damage was assessed by employing biochemical parameters (transaminase enzyme levels in plasma and liver [AST-aspartate transaminase; ALT-alanine transaminase, LDH-lactate dehydrogenase]). Further, markers of hepatic oxidative damage were measured in terms of malondialdehyde (MDA), enzymic antioxidants (CAT, SOT, GST, GPX) and GSH (reduced glutathione) levels. In addition, the CCl(4)-induced pathological changes in liver were evaluated by histopathological studies. Our results demonstrated that pretreatment of rats with PPE significantly prevented the increased activities of AST and ALT in serum, prevented the elevation of hepatic MDA formation as well as protected the liver from GSH depletion. PPE pretreatment also restored CCl(4)-induced altered antioxidant enzyme activities to control levels. The protective effect of PPE was further evident through the decreased histological alterations in liver. Our findings provide evidences to demonstrate that PPE pretreatment significantly offsets CCl(4)-induced liver injury in rats, which may be attributable to its strong antioxidant propensity.     

The effect of N-acetylcysteine (NAC) on liver and renal tissue inducible nitric oxide synthase (iNOS) and tissue lipid peroxidation in obstructive jaundice stimulated by lipopolysaccharide (LPS).

Morbidity and mortality rates are very high in obstructive jaundice when it is associated with sepsis and multiple organ failure. Nitric oxide (NO) formation and increased expression of inducible nitric oxide synthase (iNOS) also take place in obstructive jaundice (OJ). N-Acetylcysteine (NAC) has a beneficial effect by demonstrating anti-inflammatory activity such as inhibits cytokine expression/release, inhibiting the adhesion molecule expression and inhibiting nuclear factor kappa B (NFkappaB). The aim of this study was to investigate the effects of NAC on liver and renal tissue iNOS, and liver tissue lipid peroxidation in lipopolysaccharide (LPS) induced obstructive jaundice. We randomized 48 rats into six groups. Group A: Sham group; group B: OJ group; group C: OJ+NAC; group D: OJ+LPS (Escherichia coli LPS serotype L-2630, 100mg, Sigma) group E: OJ+NAC+LPS; group F: OJ+LPS+NAC. NAC was started subcutaneously 100mg/kg. LPS was injected intraperitoneally and then at the tenth day we sacrificed the rats.Liver malondialdehyde (MDA) increased and liver ATPase decreased in groups B-D when compared to group A. After the administration of NAC (groups C-E), liver MDA levels decreased, tissue ATPase levels increased as compared to other groups. The liver and renal tissue iNOS expression was increased in groups B, D, and F. After the administration of NAC (groups C-E) the liver and renal tissue iNOS expression were decreased. Our results indicated that NAC prevented the deleterious effects of LPS in OJ by reducing iNOS expression via lipid peroxidation in liver and renal tissue; if it was administrated before LPS. But NAC failed to prevent the iNOS expression and lipid peroxidation if there was established endotoxemia in OJ.     

藏药三果汤调节Nrf2/HO-1信号通路干预高脂血症大鼠的作用机制

目的 基于Nrf2/HO-1信号通路探讨藏药三果汤对高脂血症大鼠保护作用及相关作用机制。方法 雄性SD大鼠48只,随机分为6组,即正常对照组、模型对照组、辛伐他汀组(3.5 mg·kg^-1),藏药三果汤低、中、高剂量组(0.43,0.86,1.72 g·kg^-1),每组8只。正常对照组给予基础饲料喂养,其余各组给予H10060高脂饲料喂养,制备高脂血症大鼠模型,造模的同时,各给药组每天1次给予相应药物灌胃,正常对照组、模型对照组给予等体积的生理盐水(1次·d-1),连续灌胃6周。实验期间每周固定时间称取各组大鼠体质量1次,6周后试剂盒检测血清中血脂[总胆固醇(totalcholesterol,TC)、甘油三酯(triglyceride,TG)、低密度脂蛋白(low density lipoprotein,LDL)、高密度脂蛋白(high density lipoprotein,HDL)]及氧化指标[丙二醛(malondialdehyde,MDA)、超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽(glutathio...