硫化氢/胱硫醚-γ-裂解酶在内毒素性急性肺损伤发生中的作用

目的 探讨硫化氢/胱硫醚-γ-裂解酶(H2S/CSE)体系在内毒素所致大鼠急性肺损伤(ALI)中的作用并初探其机制.方法 将64只SD大鼠随机分为对照组、ALl组(经气管内滴注脂多糖(LPS)复制ALI模型]、硫氢化钠(NaHS)组和炔丙基甘氨酸(PPG)组,各组再分为给药后4 h和8 h亚组,每个亚组8只.于各时间点处死动物,光镜下观察肺组织病理学改变;化学法检测血浆H2S、一氧化氮(NO)和一氧化碳(CO)含量、肺组织丙二醛(MDA)含量、髓过氧化物酶(MPO)、CSE、诱生型一氧化氮合酶(iNOS)和血红素加氧酶(HO)活性;放射免疫法检测肺组织P-选择素含量,用免疫组化法检测肺组织iNOS、HO-1的蛋白表达.结果 气管内滴注LPS可引起肺组织明显的病理学改变;肺组织MDA含量、MPO活性和P-选择素水平升高,血浆iNOS、HO活性和肺组织iNOS、HO-1蛋白表达增强,血浆NO、CO含量增加,血浆H2S含量和肺组织CSE活性下降(P<0.05或P<0.01).预先给予NaHS可显著减轻内毒素所致上述指标的改变;而预先给予PPG可加重内毒素所致肺损伤,使肺组织MDA含量、MPO活性、P-选择素水平,血浆NO含量,肺组织iNOS活性和iNOS蛋白表达进一步增加,但对血浆CO含量、肺组织HO活性和HO-1蛋白表达无明显影响.结论 H2S/CSE体系的下调在内毒素所致大鼠ALI的发病学中有一定作用,内、外源性H2S具有抗内毒素所致ALI的作用,该作用可能与其抗氧化效应、减轻中性粒细胞所致肺过度的炎症反应以及下调NO/iNOS体系、上调CO/HO-1体系有一定关系.     

血红蛋白氧合酶在妊娠期高血压疾病发病中的作用

目的探讨血红蛋白氧合酶（hemeoxygenase，HO）的生理状态下主要存在形式血红蛋白氧合酶-1、血红蛋白氧合酶-2在妊娠期高血压疾病（hypertensive disorder complicating pregnancy）患者与正常晚孕妇女胎盘中的表达规律，以及其产物一氧化碳（carbon monoxide，CO）在外周血的变化，研究血红蛋白氧合酶在妊娠期高血压疾病发病中的作用。方法选取2005年5月至2005年12月在山西医科大学第一医院刮宫产分娩的56例孕妇为研究对象，采用原位杂交技术和免疫组化法检测30例妊娠期高血压疾病患者（观察组，其中，观察组A患者为8例．观察组13为22例）与26例正常晚孕妇女（对照组）胎盘组织中HO-1mRNA，HO-2mRNA的表达和定位。并应用血气仪检测外周血中碳氧血红蛋白（COHb）的变化。结果①HO-1mRNA和HO-2mRNA在观察组胎盘滋养细胞及血管内皮细胞中的表达与对照组比较，差异无显著意义（P〉0．05）。②血红蛋白氧合酶-1在观察组胎盘滋养细胞中的表达，明显低于对照组，两组比较，差异有显著意义（P〈0．05）；血红蛋白氧合酶2在观察组胎盘滋养细胞和血管内皮细胞中表达，均明显低于对照组，与对照组比较，差异有显著意义（P〈0．05），并且随着妊娠期高血压疾病病情的加重，血红逐逝越弱，与对照组对比，差异有显著意义（P〈0.05）。③碳氧血红蛋白在观察组外周血中的水平明显低于对照组，两组比较，差异有显著意义（P〈0．05）。结论血红蛋白氧合酶可能参与妊娠期高血压疾病的发生。     

Isorhamnetin protects against oxidative stress by activating Nrf2 and inducing the expression of its target genes

Isorhamentin is a 3′-O-methylated metabolite of quercetin, and has been reported to have anti-inflammatory and anti-proliferative effects. However, the effects of isorhamnetin on Nrf2 activation and on the expressions of its downstream genes in hepatocytes have not been elucidated. Here, we investigated whether isorhamnetin has the ability to activate Nrf2 and induce phase II antioxidant enzyme expression, and to determine the protective role of isorhamnetin on oxidative injury in hepatocytes. In HepG2 cells, isorhamnetin increased the nuclear translocation of Nrf2 in a dose- and time-dependent manner, and consistently, increased antioxidant response element (ARE) reporter gene activity and the protein levels of hemeoxygenase (HO-1) and of glutamate cysteine ligase (GCL), which resulted in intracellular GSH level increases. The specific role of Nrf2 in isorhamnetin-induced Nrf2 target gene expression was verified using an ARE-deletion mutant plasmid and Nrf2-knockout MEF cells. Deletion of the ARE in the promoter region of the sestrin2 gene, which is recently identified as the Nrf2 target gene by us, abolished the ability of isorhamnetin to increase luciferase activity. In addition, Nrf2 deficiency completely blocked the ability of isorhamnetin to induce HO-1 and GCL. Furthermore, isorhamnetin pretreatment blocked t-BHP-induced ROS production and reversed GSH depletion by t-BHP and consequently, due to reduced ROS levels, decreased t-BHP-induced cell death. In addition isorhamnetin increased ERK1/2, PKCδ and AMPK phosphorylation. Finally, we showed that Nrf2 deficiency blocked the ability of isorhamnetin to protect cells from injury induced by t-BHP. Taken together, our results demonstrate that isorhamnetin is efficacious in protecting hepatocytes against oxidative stress by Nrf2 activation and in inducing the expressions of its downstream genes.     

血红素氧合酶在子痫前期胎盘组织中的表达及意义

目的探讨子痫前期患者胎盘组织中血红素氧合酶（HO）的两种同工酶蛋白的表达及意义。方法应用免疫组织化学法对20例子痫前期患者（PE组）及20例正常产妇（对照组）胎盘组织中的HO-1和HO-2蛋白进行检测分析，同时测定两组产妇血清HO活性。、结果对照组中，HO-1蛋白在胎盘血管内皮细胞的表达量明显低于HO-2蛋白（P〈0．05）；在胎盘滋养细胞中两者表达量没有差别（P〉0．05）；PE组胎盘组织中HO-1蛋白的表达与对照组比较，差异无显著性（P〉0．05）；HO-2蛋白的表达明显降低，与对照组有显著差异（P〈0．05）；PE组HO活性显著低于对照组（P〈0．05）。结论子痫前期胎盘组织中HO-2表达减弱，活性降低，可能是妊娠期高血压疾病发病的机制之一。     

栀子总环烯醚萜苷对脑出血大鼠血红素氧合酶-1表达的影响

目的研究栀予总环烯醚萜苷对大鼠脑出血（ICH）后血肿周围脑组织血红素氧合酶-1（HO-1）表达及抗氧化能力的影响。方法将SD大鼠随机分为假手术组、脑出血模型组和栀予总环烯醚萜苷（20，10，5mg／kg）组，采用自体血注入诱发大鼠脑出血模型，每组分别在术后12，24，48，72和144h5个时间点取脑组织标本，免疫组化检测HO-1表达，同时测量脑组织SOD活性和MDA含量。结果20～10mg／kg栀予环烯醚萜苷组脑出血后HO—1表达水平及脑组织MDA含量明显低于脑出血组（P〈0．05），SOD活性明显高于脑出血组（P〈0．05）。结论栀予总环烯醚萜苷可以抑制脑出血后HO-1表达，增强抗氧化能力，从而减轻脑水肿。     

The many faces of nitric oxide: cytotoxic, cytoprotective or both

Nitric oxide (NO) has emerged as a major modulator of cellular function in health and disease. In addition to its well-known role as a mediator of smooth muscle relaxation, a rapidly developing body of research suggests, paradoxically, that NO can have both cytotoxic and cytoprotective effects. In this issue of Neurogastroenterology and Motility, Choi et al. provide evidence that supports NO has a prosurvival effect on interstitial cells of Cajal in the mouse stomach. The objective of this short review is to place this interesting report in the context of the current literature.     

血红素氧合酶在门静脉高压症患者脾动脉中的异常表达

目的研究血红素氧合酶(HO)在门静脉高压症患者脾动脉的表达,探讨血红素氧合酶-内源性一氧化碳系统(HO-CO)在门静脉高压症演进过程中的作用。方法收集门静脉高压症并行择期脾切除加贲门周围血管离断术患者18例,同期外伤性脾破裂行脾切除术患者12例为对照,取脾动脉组织,应用半定量逆转录聚合酶链反应(RT-PCR)检测HO-1、HO-2 mRNA表达,Western blot检测其蛋白表达。结果HO-1 mRNA和蛋白表达的吸光度比值在对照组为(0.03±0.00)、(0.04±0.01),均明显低于门静脉高压组(0.81±0.12)、(1.56±0.25),差异均有极显著性意义(P<0.01);HO-2 mRNA和蛋白表达在对照组为(0.64±0.12)、(0.84±0.14),在门静脉高压组为(0.58±0.09)、(0.92±0.12),差异均无显著性意义(P>0.05)。HO-1表达与肝功能分级相关,肝功能Ⅱ级患者其脾动脉HO-1 mRNA和蛋白表达均明显高于肝功能Ⅰ级患者(P<0.01);HO-2表达与肝功能分级无相关关系(P>0.05)。结论HO-CO系统,尤其是HO-1在门静脉高压症演进过程中起重要作用。     

青心酮对活化RAW264.7细胞株血红素氧合酶-1mRNA/一氧化碳及TNF-α表达的影响

目的观察青心酮对活化 RAW264.7细胞株血红素氧合酶-1mRNA/一氧化碳(Hemeoxygenase-1/carbon monoxide,HO-1mRNA/CO)及肿瘤坏死因子-α(TNF-α)表达的影响。方法用 LPS 做刺激剂,建立活化细胞模型。分别用 RT-PCR 法检测 HO-1mRNA 的表达,血红蛋白结合法检测 CO 的相对含量,Western-blot 方法检测 TNF-α蛋白质的表达。结果 10~(-5)mol/L 青心酮使活化巨噬细胞 HO-1mRNA 表达增加,CO 增加,TNF-α蛋白表达下降。结论青心酮上调活化 RAW264.7细胞株 HO-1mRNA/CO 的表达,抑制 TNF-α蛋白的产生,这可能是 DHAP 抗炎作用机制之一。     

Effect of zinc protoporphyrin on carbon monoxide/heme oxygenase-1 system in rats subjected to recurrent febrile convulsion

BACKGROUND: Studies on febrile convulsion (FC)-caused brain injury are disputed in many aspects. How FC cause nervous system injury in the developmental period and what are the characteristics of these pathological injury are unknown. The current studies have demonstrated that heme oxygenase-1 (HO-1) exerts effects on brain injury mainly by catalyzing hemoglobin to produce degradation products, and HO-1 not only has neuroprotective effects, but also has neurotoxic effects during the FC-caused brain injury. Study on the effect of zinc protoporphyrin (ZnPP) on brain injury is still in the stage of animal experiment. OBJECTIVE: To observe the effects of ZnPP on carbon monoxide (CO)/HO-1 system of rats subjected to FC, and to analyze the action pathway of ZnPP in brain protective effect. DESIGN: A randomized controlled animal experiment. SETTING: Department of Pediatrics, First Hospital Affiliated to Jiamusi University. MATERIALS: Sixty-five Wistar rats, of either gender, were involved in this study. They were randomized into normal control group( n =14, 37 ℃ water bath) and febrile treatment group (n =51, 44.5 ℃ hot water bath). Febrile treatment group was sub-divided into febrile non-convulsion group (FNC group, n =16) and FC group (n =35). FC group was further sub-divided into simple convulsion group (n =20) and ZnPP treatment group (n =15). HO-1 mRNA in situ hybridization kit was provided by Boster Bioengineering Co.,Ltd. ZnPP(dark brown powder) was the product of Jingmei Bioengineering Company. METHODS: This study was carried out in the postgraduate laboratory of Jiamusi University between January 2004 and January 2007. Rats in the febrile treatment group were placed in the 44.5 ℃ hot water bath box. If rats did not convulse in the water within 5 minutes, they were taken out, namely FNC group (n = 16), and those, which were convulsed within 5 minutes, were taken out immediately when they presented such a phenomenon, namely FC group (n =35). Convulsion induction was conducted once every other day, totally 10 times. Rats were euthanized for analysis at 24 hours after the last induction. Rats in the control group were placed in the 37 ℃ water. Rats in the ZnPP treatment group were intraperitoneally injected with ZnPP at 45 μmol/kg before FC attack. Rats in the simple convulsion group were only induced to be convulsed but not administrated. MAIN OUTCOME MEASURES: CO level in the brain tissue homogenate and plasma of rats in each group was detected with a spectrophotometer. HO-1 mRNA expression in the hippocampal CA1 region, CA3 region and dentate gyrus of rats was observed by in situ hybridization technique. RESULTS: Sixty-five Wistar rats were involved in the study. Two rats died respectively due to drowning and convulsion in the FC group. One rat died due to convulsion drowning in the ZnPP treatment group. ① Plasma CO concentration of control group and ZnPP treatment group was significantly lower than that of the FC group (P < 0.01), and was significantly higher in the ZnPP treatment group than in the FNC group (P < 0.05). ② CO level in the brain tissue homogenate was significantly lower in the control group and ZnPP treatment group than in the FC group (P < 0.01), and was very significantly higher in the ZnPP treatment group than in the control group (P < 0.01). ③ HO-1 mRNA expressions in the neuron of hippocampal CA1 region, CA3 region and dentate gyrus of the control group were the lowerest, and those in the FC group were the highest. HO-1 mRNA expression in the neuron of dentate gyrus in the FC group was significantly higher than that in the ZnPP treatment group (P < 0.01), and those in the FNC group and control group was significantly lower than that in the ZnPP treatment group (P < 0.01). CONCLUSION: FC can cause brain injury. Over-expression of HO-1 mRNA and the increase of CO are involved in the patho-physiological process of FC. ZnPP can inhibit HO-1mRNA activity and decrease CO level, which is one of pathways for protecting brain.