血根碱对脂多糖致H9c2细胞氧化损伤的改善作用

目的 观察血根碱（sanguinarine,SAN）对脂多糖（lipopolysaccharide,LPS）诱导的H9c2细胞氧化应激的影响,并对其与HO-1/NOX2途径之间的关系进行探讨。方法 不同因素干预H9c2细胞后,采用细胞活性试剂盒检测不同浓度SAN和/或LPS对H9c2细胞生存的影响;酶标仪及荧光显微镜检测SAN对LPS诱导细胞产生活性氧（reactive oxygen species,ROS）的影响; Real time RT-PCR检测SAN对LPS诱导的NOX2、P47PHOX、HO-1、SOD1、SOD2基因表达的影响; MDA检测试剂盒检测MDA的变化。结果 单用SAN对H9c2细胞活性无影响,LPS可显著降低细胞活性,而SAN与LPS共同干预则可呈浓度依赖性地提高细胞活性,降低ROS产生。LPS处理12 h上调H9c2细胞NOX2、p47phox mRNA表达、下调HO-1 mRNA表达; SAN预处理后,细胞内NOX2、p47phox mRNA下调、HO-1 mRNA上调,而SAN与锌原卟啉IX预处理则可逆转这种现象。SAN上调SOD1及SOD2 mRNA表达,降低MDA产生。结论 SAN可通过活化HO-1/NOX2途径,抑制ROS的产生,从而使H9c2细胞免受LPS介导的损伤,提高细胞活力。     

黄芩素-7-甲醚对缺氧致PC12细胞损伤的保护作用

目的 研究黄芩素-7-甲醚对缺氧PC12细胞的保护作用。方法 将PC12细胞分为正常对照组、缺氧模型组、芦丁组和黄芩素-7-甲醚组,培养24 h后,MTT法检测黄芩素-7-甲醚对细胞活力的影响;酶标仪法检测细胞培养上清液中乳酸脱氢酶（lactate dehydrogenase,LDH）活性以及细胞内丙二醛（malondialdehyde,MDA）、超氧化物歧化酶（superoxide dismutase,SOD）和过氧化氢酶（catalase,CAT）水平;2'',7''-二氯荧光素探针法检测细胞内活性氧簇（reactive oxygen species,ROS）水平;实时荧光定量PCR和Western blot检测核因子E2相关因子2（Nrf2）和血红素氧合酶-1（heme oxygenase-1,HO-1）的mRNA和蛋白的表达。结果 与正常对照组相比,缺氧导致PC12细胞活力显著降低,LDH、MDA和ROS水平显著升高,抗氧化酶SOD和CAT的活力显著降低。黄芩素-7-甲醚预处理能够逆转这些变化。此外,缺氧能够诱导细胞内Nrf2、HO-1的mRNA和蛋白表达增加,而黄芩素-7-甲醚能够进一步提高Nrf2、HO-1的mRNA和蛋白表达。结论 黄芩素-7-甲醚对缺氧致PC12细胞损伤有一定的保护作用,其作用机制可能与激活Nrf2/HO-1通路,抑制氧化应激损伤有关。     

Ferrostatin-1通过抑制铁死亡延缓D-gal诱导的心肌细胞衰老的研究

目的 探讨D-半乳糖（D-gal）诱导的心肌细胞衰老是否存在铁死亡及铁死亡抑制剂Ferrostatin-1(Fer-1)能否延缓心肌细胞衰老。方法 通过不同水平（0、5、10、20、40、80、100 g/L）D-gal诱导H9C2心肌细胞损伤从而制备心脏衰老模型,采用MTT法检测细胞活力,确定后续实验采用的D-gal质量浓度。将细胞分为Control组、D-gal组和Fer-1组。MTT法检测细胞活力;DCFH-DA法检测细胞内活性氧（ROS）水平;微板法检测细胞内还原型谷胱甘肽（GSH）含量;硫代巴比妥酸法检测细胞内丙二醛（MDA）含量;Western blot检测溶质载体家族7成员11(SLC7A11)、谷胱甘肽过氧化物酶4(GPx4)、P53蛋白表达水平;微量法检测细胞内β-半乳糖苷酶（β-GAL）活性。结果 MTT法结果显示,细胞活力随D-gal质量浓度升高而降低（P<0.05）,后续实验采用D-gal质量浓度为20 g/L。与D-gal组相比,Fer-1组细胞活力增加（P<0.05）;与Control组相比,D-gal组中ROS、MDA含量、P53蛋白表达水平、...     

Improving effect and mechanism of fisetin on cell model of diabetic cerebral microangiopathy

OBJECTIVE To explore the effect and mechanism of fisetin on prevention and treatment of diabetic cerebral microangiopathy at the cellular and molecular level. METHODS In vitro experiments, high glucose(HG, 25 mmol·L~(-1)) and palmitic acid(PA, 200 μmol·L~(-1))were used to intervene in the mouse brain microvascular endothelial cells to establish the model of diabetic brain microangiopathy. Groups are divided into control, model(25 mmol·L~(-1) HG+200 μmol·L~(-1) PA, HG+PA) and fisetin(1, 5, 10 and 20 μmol·L~(-1)) groups. The effect of fisetin on hyperglycemic and hyperlipid-induced cell damage was detected by cell counting kit-(CCK-) 8 assay, cytotoxicity was detected by LDH assay. After treatment, the changes of oxidative stress related factors(ROS, NO, i NOS, MMP-2, MMP-9, TIMP-1, MDA, SOD, CAT) were detected by ELISA. RESULTS Compared with the control group, the cell viability of model group was significantly reduced(P<0.01), indicating that the model was successful y prepared.LDH content, the expression levels of ROS, NO, i NOS,MMP-2, MMP-9, TIMP-1 and MDA in the model group significantly increased(P< 0.01), while the expression of SOD and CAT in the model group decreased significantly(P<0.01). Compared with the model group, the activity of the cells, in the fisetin group was significantly increased(P<0.01). LDH content, the expression levels of ROS,NO, i NOS, MMP-2, MMP-9, TIMP-1 and MDA were decreased in the fisetin group(P<0.01), the expression of SOD and CAT, were significantly increased(P<0.01).The expression levels of antioxidant proteins HO-1 and NQO1 were significantly increased in the fisetin group(P<0.05). CONCLUSION Fisetin can improve the cell injury induced by HG and PA, which mimic the diabetic cerebral microvascular lesions, and its mechanism might be related to inhibiting the production of endogenous ROS in cells, activating the expression of antioxidant proteins and inhibiting the production of related oxidative factors.     

电针调控Nrf2/HO-1通路对缺血缺氧性脑损伤大鼠小胶质细胞活化的影响

目的 探究电针调控核因子E2相关因子2(Nrf2)/血红素加氧酶1(HO-1)通路对缺血缺氧性脑损伤（HIBD）大鼠小胶质细胞活化的影响。方法 随机将40只SD大鼠均分为假手术组、模型组、电针组、电针+全反式维甲酸组。除假手术组外其余组均通过颈总动脉结扎及缺氧建立HIBD大鼠模型,假手术组大鼠仅暴露左侧颈总动脉及迷走神经,不进行结扎及缺氧处理。造模结束后,电针组于百会穴进行电针刺激;电针+全反式维甲酸组大鼠经电针刺激后腹腔注射全反式维甲酸（7 mg/kg）。通过Longa评分进行大鼠神经行为学评分;旷场及水迷宫实验检测大鼠自主活动能力和认知功能;TUNEL法检测大鼠神经细胞凋亡情况;免疫组化法检测大鼠脑组织中小胶质细胞标志蛋白离子钙结合衔接分子1(Iba1)表达;试剂盒检测大鼠脑组织中白细胞介素10(IL-10)、IL-1β、活性氧（ROS）及丙二醛（MDA）水平;Western blot检测脑组织CD68、诱导型一氧化氮合酶（iNOS）和精氨酸酶（Arginase）及Nrf2/HO-1通路相关蛋白表达。结果 与假手术组比较,模型组大鼠神经行为学评分、逃避潜伏期、大脑皮质神经细胞凋亡率...     

Heme-oxygenase-1 promotes polychlorinated biphenyl mixture aroclor 1254-induced oxidative stress and dopaminergic cell injury.

Dopaminergic (DAergic) systems have been identified as putative targets for polycholorinated biphenyl (PCB) actions. However, the precise mechanisms leading to neurotoxicity are unresolved. Reactive oxygen species (ROS) were recently shown to mediate injury in DAergic MN9D cells following exposure to Aroclor 1254 (A1254), a commercial PCB mixture. The oxidative stress response in DAergic cells included a persistent expression of heme oxygenase-1 (HO-1). This study tested the hypothesis that a sustained PCB-induced HO-1 response leads to abnormally high Fe levels, which generates ROS production and mediates death in the MN9D DAergic cell model. Accordingly, results indicated that A1254 augmented intracellular Fe levels in MN9D cells after 24 h. Fe chelation by desferoxamine or pharmacologic inhibition of HO activity with tin-protoporphyrin reduced Fe accumulation, ROS production, and cytotoxicity following A1254 exposure. HO-1 over-expression predisposed MN9D DAergic cells to enhanced ROS production and cell death in response to PCBs. Conversely, antisense inhibition of HO-1 expression prevented PCB-induced ROS production and cell death. These observations suggest that enhanced HO-1 catalytic activity and subsequent liberation of Fe participate in neurotoxic DAergic cell injury caused by A1254 exposure in vitro.     

美洲大蠊提取物对H2O2诱导的PC12细胞氧化损伤的保护作用

目的:探讨美洲大蠊提取物(PAS840)对大鼠肾上腺嗜铬细胞瘤(PC12)细胞氧化损伤模型的保护作用及机制。方法:采用H₂O₂刺激PC12细胞建立神经细胞氧化损伤模型,实验分为正常组(Con)、模型组(Mod)、PAS840低中高剂量组(20,50,125 μg·mL^-1的PAS840培养基溶液进行处理),采用倒置显微镜观察细胞形态并采用CCK-8法检测各组细胞存活率,生化试剂盒检测各组超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、乳酸脱氢酶(LDH)、谷胱甘肽(GSH)和丙二醛(MDA)的水平;DCFH-DA荧光探针检测各组活性氧簇(ROS)的水平;流式细胞术检测各组细胞凋亡率;JC-1法染色检测各组细胞线粒体膜电位(MMP);RT-qPCR检测各组Nrf2/HO-1通路因子(Nrf2、Keap1、HO-1和NQO1)、凋亡因子(Bcl-2、Bax和Caspase-3)、炎症因子(TNF-α、IL-1β和IL-6)、乙酰胆碱酯酶(AchE)和过氧化氢酶(CAT) mRNA的表达水平;Western blot法检测各组Nrf2、HO-1、Bcl-2、Bax和Caspase-3蛋白的表达水平。结果:PAS840可显著提高氧化损伤细胞的存活率、MMP及SOD、GSH-Px和GSH的水平,降低LDH、MDA和ROS的水平;显著降低Keap1、TNF-α、IL-1β、IL-6和AchE mRNA表达的同时,显著增加CAT和NQO1 mRNA的表达,显著降低Nrf2、Bax和Caspase-3的mRNA及其蛋白表达,显著增加HO-1和Bcl-2的mRNA及其蛋白表达。结论:PAS840可以抑制H₂O₂诱导的PC12细胞凋亡,减轻炎症,其机制可能与降低ROS、调控Nrf2/HO-1通路因子减轻细胞的氧化损伤程度有关。     

Protective effect of isorhamnetin 3-О-β-d-glucopyranoside from Salicornia herbacea against oxidation-induced cell damage

Isorhamnetin 3-О-β-d-glucopyranoside (1) was isolated from Salicornia herbacea. The inhibitory effects of compound 1 on oxidative stress were evaluated in free-cellular and cellular systems. An increased concentration of compound 1 not only exhibited dose-dependent scavenging activities on the generation of 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl and carbon-centered radicals, but also significantly decreased levels of intracellular reactive oxygen species (ROS) in a dose-dependent manner. Further, antioxidative mechanisms by compound 1 were examined by measuring the intracellular glutathione (GSH) level and expression levels of antioxidant enzymes such as superoxide dismutase (SOD), catalase, glutathione reductase and heme oxygenase-1 (HO-1). Compound 1 significantly elevated GSH level as well as expression levels of antioxidant enzymes which were closely related with amount of cellular ROS. In addition, it significantly inhibited oxidative damage of purified genomic DNA and suppressed activity of myeloperoxidase (MPO), a generator of potent oxidant (hypochlorous acid), in tumor necrosis factor-α (TNF-α) stimulated human myeloid cells. Therefore, these results suggested that compound 1 has a therapeutic effectiveness in prevention of ROS-induced cellular damage and is a candidate worthy of being developed as a potential natural antioxidant related to oxidative stress.     

Tempol对高原缺氧致小鼠脑组织损伤的保护作用

目的：研究Tempol对高原缺氧小鼠脑组织的保护作用及其机制。方法：将60只小鼠随机分为正常对照组、缺氧模型组、乙酰唑胺组和Tempol组,单次腹腔注射给药后,在模拟海拔8 000 m环境停留12 h,检测脑组织中H₂O₂、MDA、ATP酶和抗氧化酶的活性变化,蛋白印迹法检测HIF-1α、VEGF、Nrf2和HO-1蛋白的表达情况。结果：与正常对照组相比,缺氧模型组中H₂O₂和MDA含量显著增加,ATP酶和抗氧化酶活性显著减低,HIF-1α、VEGF、Nrf2和HO-1x蛋白表达增强。经Tempol预处理后能够显著降低高原缺氧小鼠脑组织中H₂O₂和MDA含量,提高抗氧化酶和ATP酶活性,降低HIF-1α和VEGF蛋白表达,显著提高Nrf2和HO-1蛋白的表达。结论： Tempol能够减轻高原缺氧脑组织损伤,作用机制可能与其能清除自由基,激活Nrf2/HO-1信号途径,提高抗氧化酶活性,降低机体氧化应激,改善能量代谢有关。     

Adverse effect of tannery waste leachates in transgenic Drosophila melanogaster: role of ROS in modulation of Hsp70, oxidative stress and apoptosis

Leachate is a complex chemical mixture of chemicals produced as a result of leaching of solid wastes. The potential toxicity of leachates is a major environmental health concern. The present study evaluated the role of ROS in tannery leachates induced Hsp70 expression, antioxidant enzymes and apoptosis in Drosophila. Different concentrations (0.05-2.0%) of leachates prepared from tannery waste at different pH (7.00, 4.93 and 2.88) were mixed with Drosophila food and fed to the larvae for 2-48 h to examine the different stress and apoptotic markers. A concentration- and time-dependent significant increase in Hsp70 expression, ROS generation, antioxidant enzymes activities and MDA content were observed in the exposed larvae. Activities of antioxidant enzymes were delayed compared with Hsp70 expression and MDA level in the exposed organisms. Apoptotic cell death was observed in the exposed larvae at higher concentrations concurrent with a significant regression in Hsp70 along with a higher level of ROS generation. A positive correlation drawn between ROS generation and apoptotic markers and a negative correlation between apoptotic markers and Hsp70 expression at these concentrations indicated the important role of ROS in the induction of cellular damage in the exposed organisms. There was a significant generation of ROS in the larvae exposed to 0.5% of leachates which did not interfere with the protection of their cells by Hsp70 and antioxidant enzymes. However, generation of significantly higher levels of ROS in the larvae exposed to 1.0% and 2.0% leachates may decrease Hsp70 expression thus leading to mitochondria-mediated caspase-dependent apoptotic cell death.     

β-榄香烯抗氧化损伤作用的实验研究

目的:利用内皮细胞氧化损伤模型和鹌鹑饵食性高脂血症模型,研究β-榄香烯的抗氧化损伤作用.方法:采用过氧化氢(H2O2)建立体外培养的人脐静脉内皮细胞(HUVEC)氧化损伤模型,观察不同浓度(0.1、1、10 mg/L)β-榄香烯对细胞内活性氧水平、丙二醛(MDA)含量和超氧化物岐化酶(SOD)活性的影响;采用高脂饲料喂养法建立鹌鹑高脂血症模型,观察β－榄香烯对鹌鹑血清SOD活性、MDA和一氧化氮(NO)含量的影响.结果:β-榄香烯可降低内皮细胞内活性氧水平,升高SOD活力,降低MDA含量;β-榄香烯升高鹌鹑血清中SOD活性和NO含量,降低MDA水平.结论:β－榄香烯具有较强的抗氧化、清除氧自由基及保护血管肉皮细胞作用.     

甘草萜醇类共轭烯衍生物的合成及抗氧化活性

为优化甘草次酸(Ib)的抗氧化活性，对其化学结构进行修饰，通过还原和脱水反应制备了2个甘草萜醇类共轭烯衍生物。各化合物的抗氧化活性由肝微粒体中的细胞色素P450/NADPH氧化系统做体外抗氧化实验模型进行测定。微粒体中的自由基诱发情况由探针DCFH-DA的氧化程度进行检测，维生素E作为阳性对照物。初步的活性测定结果显示，甘草萜醇类两种同环和异环双烯衍生物——18β-olean-11,13(18)-diene-3β,30-diol (IV)和18β-olean-9(11),12-diene-3β,30-diol(V)显示出较强的抗氧化活性，以1.0 mg·mL^-1的浓度，分别抑制自由基活性为45%和41%。相同条件下，先导物Ib和维生素E分别抑制31%和32%的自由基活性。此结果显示，对先导物Ib的C11位羰基的脱去和C30位羧基进行还原修饰，可显著提高其抗氧化活性。     

咖啡酸苯乙酯通过Nrf-2途径抑制地塞米松诱导的成骨细胞凋亡

目的 探讨Nrf-2途径在咖啡酸苯乙酯(CAPE)抑制地塞米松(DEX)诱导成骨细胞凋亡中的作用.方法 用细胞贴壁法培养小鼠颅顶前骨细胞(MC3T3-E1),采用10μmol/L DEX建立细胞损伤模型,以不同浓度CAPE(0.05、0.25、1μmol/L)预处理细胞2h后加入地塞米松共孵育24h;细胞增殖-毒性检测试剂盒(CCK-8)检测细胞增殖活性;依据CCK-8检测结果确定药物浓度后将实验分为对照组、咖啡酸苯乙酯组(CAPE组)、地塞米松组(DEX组),咖啡酸苯乙酯+地塞米松组(CAPE+DEX组);DCFH-DA荧光探针检测细胞内活性氧(reactive oxygen species,ROS)水平;Caspase-3活性检测试剂盒检测Caspase-3酶活性,Western blot法检测Nrf-2 途径相关蛋白Nrf-2和血红素氧合酶1(heme oxygenase,HO-1)蛋白表达水平;流式细胞仪检测细胞凋亡率.结果 10μmol/L DEX作用下细胞形态发生明显变化,损伤作用明显.与对照组相比,DEX组内细胞存活率显著下降(P＜0.01),而细胞内 ROS水平、细胞凋亡率及Caspase-3酶活性显著增加(P＜0.01);同时,Nrf-2途径相关蛋白 Nrf-2及HO-1表达量减少,差异有统计学意义(P＜0.01).与DEX组相比,CAPE+DEX组细胞存活率显著上升(P＜0.01),Nrf-2途径相关蛋白 Nrf-2及HO-1表达明显增加(P＜0.01);此外,CAPE+DEX组细胞内 ROS 水平、细胞凋亡率及Caspase-3酶活显著降低,差异有统计学意义(P＜0.01).结论 咖啡酸苯乙酯可以通过Nrf-2途径降低细胞内ROS水平进而减轻地塞米松诱导的氧化应激所致细胞损伤及凋亡.     

Poria cocos polysaccharides attenuated ox-LDL-induced inflammation and oxidative stress via ERK activated Nrf2/HO-1 signaling pathway and inhibited foam cell formation in VSMCs

Oxidative stress, inflammation, and foam cell formation in vascular smooth muscle cells (VSMCs) are considered to play crucial roles in the pathogenesis of atherosclerosis. Poria cocos polysaccharides (PCP) has been shown to possess anti-inflammatory, antitumor and anti-oxidative properties. In this study we explored the effects of PCP on ox-LDL-induced inflammation, oxidative stress and foam cell formation in VSMCs. PCP significantly attenuated ox-LDL-induced oxidative stress, as evidenced by the decreased reactive oxygen species (ROS) and MDA levels, and the increased SOD activity in VSMCs. PCP suppressed the induction effect of ox-LDL on inflammatory cytokines and inflammatory mediators. PCP also substantially inhibited VSMCs foam cell formation and intracellular lipids accumulation. Mechanistically, PCP suppressed ox-LDL-induced up-regulation of LOX-1, which is responsible for ox-LDL uptake. Western blotting suggested that PCP activated ERK1/2 signaling pathway, increased Nrf2 translocated from cytoplasm to nucleus and heme oxygenase-1 (HO-1) expression. Up-regulation of PCP on Nrf2/HO-1 signaling was reversed by pretreatment with ERK inhibitor PD98059, indicating the involvement of ERK in PCP activation of Nrf2/HO-1 signaling. In conclusion, these results demonstrated that PCP exerted its protection against oxidative stress and inflammation via the ERK/Nrf2/HO-1 signaling pathway and that PCP may be a promising candidate for the therapy of atherosclerosis.     

The cytoprotective effect of <Emphasis Type="Italic">Rumex Aquaticus Herba</Emphasis> extract against hydrogen peroxide-induced oxidative stress in AGS cells

The Rumex Aquaticus Herba extract containing quercetin-3-β-D-glucuronopyranoside (ECQ) has been reported to exhibit various pharmacological activities, including anti-inflammatory and anti-oxidative effects. This plant has been traditionally used for the treatment of diarrhea, disinfestation, edema and jaundice, and as an antipyretic drug. The aim of the present study was to investigate the ability of ECQ to protect against oxidative damage and to determine its signaling mechanism in AGS cells. The protein expressions of heme oxygenase-1 (HO-1) and nuclear factor-erythroid 2 related factor 2 (Nrf2) were measured by Western blots. Cell viability was measured by MTT assay. Intracellular reactive oxygen species (ROS) levels were measured using 2′,7′-dichlorofluorescein diacetate. Glutathione peroxidase levels were measured using kits. The protein expressions of HO-1 and its upstream mediator, Nrf2, increased after ECQ treatment. The HO-1 inhibitor, ZnPP, repressed the protective effect of ECQ on H₂O₂-induced cell damage. We found that LY294002, a specific PI3 K/Akt inhibitor, suppressed ECQ-induced HO-1 expression. ECQ significantly attenuated H₂O₂-induced cytotoxicity and ROS generation. Also, ECQ enhanced the antioxidant enzyme activities of glutathione peroxidase. These results suggest that ECQ exerts a cytoprotective effect against H₂O₂-induced oxidative stress by upregulation of Nrf2/HO-1 via the PI3 K/Akt pathway.     

Activation of Nrf2 signaling by sitagliptin and quercetin combination against β-amyloid induced Alzheimer's disease in rats

The objective of this study was to evaluate the neuroprotective effect of sitagliptin (Sita), quercetin (QCR) and its combination in β-amyloid (Aβ) induced Alzheimer's disease (AD). Male Sprague–Dawley rats, weighing between 220 and 280 g were used for experiment. Rats were divided into 5 groups (n = 10) and the groups were as follows: (a) Sham control; (b) Aβ injected; (c) Aβ injected + Sita 100; (d) Aβ injected + QCR 100; and (e) Aβ injected + Sita 100 + QCR 100. Cognitive performance was observed by the Morris water maze (MWM), biochemical markers, for example, MDA, SOD, CAT, GSH, Aβ1-42 level, Nrf2/HO-1 expression and histopathological study of rat brain were estimated. Pretreatment with Sita, QCR and their combination showed a significant increase in escape latency in particular MWM cognitive model. Further co-administration of sita and QCR significantly reduced Aβ1-42 level when compared with individual treatment. Biochemical markers, for example, increased SOD, CAT and GSH, decreased MDA were seen, and histopathological studies revealed the reversal of neuronal damage in the treatment group. Additionally, Nrf2/HO-1 pathway in rat's brain was significantly increased by Sita, QCR and their combination. Pretreatment with QCR potentiates the action of Sita in Aβ induced AD in rats. The improved cognitive memory could be because of the synergistic effect of the drugs by decreasing Aβ1-42 level, antioxidant activity and increased expression of Nrf2/HO-1 in rat brain.