硫化氢通过抑制p38 MAPK保护PC12细胞对抗化学性缺氧损伤

目的探讨硫化氢(H2S)是否通过抑制p38MAPK保护PC12细胞对抗化学性缺氧诱导的损伤。方法应用化学性低氧模拟剂氯化钴(CoCl2)处理PC12细胞建立化学性缺氧损伤模型。应用CCK-8比色法检测细胞存活率;Hochest33258核染色法观察细胞凋亡的形态学改变;双氯荧光素(DCFH-DA)染色荧光显微镜照像检测细胞内的活性氧(ROS);罗丹明123(RH123)染色荧光显微镜照像检测线粒体膜电位(MMP);Western blot法检测p38MAPK蛋白的表达水平。结果应用600μmol·L-1CoCl2处理PC12细胞2h可使磷酸化(p)p38明显增多;在应用600μmol·L-1CoCl2处理PC12细胞前30min,应用400μmol·L-1硫氢化钠(NaHS,H2S的供体)预处理细胞不仅可明显的抑制CoCl2诱导的p-p38MAPK表达的增多,还能保护PC12细胞对抗600μmol·L-1CoCl2引起的损伤,使细胞存活率升高,凋亡细胞和胞内ROS水平明显降低,MMP丢失减小;在CoCl2损伤PC12细胞前60min应用p38抑制剂SB302580(20μmol·L-1)预处理也能产生类似NaHS预处理的细胞保护作用。结论 p38MAPK介导CoCl2引起PC12细胞的损伤作用;H2S通过抑制p38MAPK的表达及氧化应激反应保护PC12细胞对抗化学性缺氧引起的损伤作用。     

原花青素对H2O2引起PC12细胞的内质网应激损伤的保护作用

目的：研究H2O2诱导PC12细胞的内质网应激损伤作用及原花青素对其预防作用。方法：H2O2 100μmol/L 诱导PC12细胞损伤18小时复制阿尔茨海默病模型（AD）,原花青素40mg/L、SB203580 10μmol/L、Tempol 800μmol/L于造模前30min预处理后,RT-PCR检测BiP/GRP-78 mRNA水平变化;流式细胞术检测细胞内反应氧产物（ROS）阳性细胞生成率,计算平均荧光强度。结果：H2O2 100μmol/L 诱导PC12细胞损伤后BiP/GRP-78 mRNA表达显著增高,ROS生成增加;原花青素40mg/L可显著降低BiP/GRP-78 mRNA水平（P〈0.01）,减少细胞内ROS生成（P〈0.01）。结论：原花青素可减轻H2O2引起PC12细胞的内质网应激损伤。     

柚皮苷保护H9c2心肌细胞对抗阿霉素诱导的心肌毒性

目的探讨柚皮苷(NRG)能否保护H9c2心肌细胞对抗阿霉素(DOX)诱导的心肌毒性。方法应用DOX处理H9c2心肌细胞建立DOX心肌损伤模型。CCK-8比色法测定细胞存活率;谷胱甘肽试剂盒检测GSSG/(GSSG+GSH)的比值;Hoechst 33258核染色法观察细胞凋亡的形态学和数量改变;Western blot法测定葡萄糖调节蛋白78(GRP78)的表达水平;双氯荧光素(DCFH-DA)染色荧光显微镜摄片检测细胞活性氧(ROS)水平;罗丹明123(Rh123)染色荧光显微镜照像测定线粒体膜电位(MMP)。结果 DOX在3⁷μmol·L-1浓度范围内处理H9c2心肌细胞24 h,呈剂量依赖性降低细胞存活率,其中5μmol·L-1DOX能明显引起心肌细胞损伤,表现为使细胞存活率下降近50%,并呈时间依赖性上调GRP78蛋白的表达;1μmol·L-1NRG预处理60min可明显抑制5μmol·L-1DOX引起的心肌毒性作用,表现为细胞存活率升高,GSSG/(GSSG+GSH)的比值下降,凋亡细胞数目减少,GRP78表达被抑制,细胞内ROS产生及MMP丢失减少。结论 NRG能保护心肌细胞对抗DOX诱导的心肌细胞损伤,保护作用可能与其抗氧化应激及内质网应激有关。     

依达拉奉保护H9c2心肌细胞对抗异丙肾上腺素诱导的氧化应激及内质网应激反应

目的探讨依达拉奉(EDA)能否保护H9c2心肌细胞对抗异丙肾上腺素(ISO)诱导的氧化应激和内质网应激(ERS)。方法用ISO处理H9c2心肌细胞,建立β1肾上腺素受体持续兴奋诱导心肌细胞毒性的体外模型。EDA在ISO处理心肌细胞前1 h加入培养基中作为预处理。CCK-8比色法检测细胞存活率;双氯荧光素(DCFH-DA)染色/荧光显微镜照相检测细胞内活性氧(ROS)的含量;罗丹明123(Rh123)染色/荧光显微镜照相检测线粒体膜电位(MMP);Western blot法检测葡萄糖调节蛋白78(GRP78)的表达。结果 ISO在20～100μmol.L-1浓度范围内处理H9c2心肌细胞48 h,呈剂量依赖性地降低细胞存活率;80μmol.L-1ISO处理H9c2心肌细胞可使细胞内ROS含量明显增多及MMP明显降低;80μmol.L-1 ISO处理H9c2心肌细胞0～24 h,可时间依赖性地上调内质网应激蛋白GRP78的表达,其中12 h达到高峰。分别用10、20和40μmol.L-1 EDA预处理1 h可以减弱80μmol.L-1 ISO处理H9c2心肌细胞48h引起的细胞存活率降低,500、1 000和2 000μmol.L-1氧自由基清除剂NAC分别预处理1 h也可减轻ISO诱导的心肌细胞毒性反应;40μmol.L-1的EDA预处理1 h可明显减轻ISO诱导的胞内ROS堆积及MMP降低,并明显抑制ISO引起的GRP78的表达上调。结论 EDA可保护H9c2心肌细胞对抗ISO诱导的损伤作用,其机制可能与抗氧化及抑制内质网应激反应有关。     

硫化氢对抗化学性缺氧引起的心肌细胞损伤及其机制

目的观察H2S对氯化钴(CoCl2)诱导的H9C2心肌细胞缺氧性损伤的影响,探讨其作用机制。方法用CoCl2处理H9C2心肌细胞,建立化学性缺氧诱导心肌细胞损伤的实验模型。NaHS(H2S的供体)在CoCl2处理H9C2心肌细胞前30 min加入培养基中,作为预处理。应用CCK-8比色法检测细胞存活率;PI染色流式细胞仪检测细胞凋亡率;Western blot法检测Cleaved Caspase-3的表达;GSSG试剂盒检测GSSG/(GSSG+GSH)的比值;双氯荧光素(DCFH-DA)染色荧光显微镜照相检测细胞内的活性氧(ROS);罗丹明123(Rh123)染色荧光显微镜照相检测线粒体膜电位(MMP)。结果在400~800μmol.L-1浓度范围内,CoCl2处理H9C2心肌细胞36 h,呈剂量依赖性地降低细胞存活率。在600μmol.L-1CoCl2处理H9C2心肌细胞前30 min,应用400μmol.L-1NaHS可明显地抑制CoCl2对细胞的损伤作用,使细胞存活率明显升高,细胞凋亡率及CleavedCaspase-3表达降低;并使H9C2心肌细胞内GSSG/(GSH+GSSG)比值及ROS水平明显降低,同时明显地改善MMP。结论H2S能明显地对抗化学性缺氧诱导的心肌细胞损伤,此保护作用与其降低GSSG/(GSH+GSSG)比值和ROS水平,改善MMP,抑制Caspase-3活化等机制有关。     

PI3K/Akt信号通路在硫化氢保护PC12细胞对抗化学性缺氧损伤的作用

目的探讨硫化氢(H2S)对PC12细胞PI3K/Akt信号通路的影响及该通路在H2S神经保护中的作用。方法Western blot法检测H2S供体硫氢化钠(NaHS)处理PC12细胞诱导Akt磷酸化的水平;CCK-8比色法检测细胞存活率;应用碘化丙啶(PI)染色流式细胞术检测细胞凋亡率。结果应用不同浓度NaHS处理PC12细胞30 min,在50～400μmol.L-1浓度范围内,呈浓度依赖性地上调Akt磷酸化的水平,但随着NaHS浓度的增加,磷酸化Akt表达量逐渐下降;Ly294002明显抑制了NaHS对Akt磷酸化水平的上调作用。NaHS预处理可以保护PC12细胞对抗600μmol.L-1CoCl2诱导的损伤,使细胞存活率提高及细胞凋亡率降低。而在预处理前使用PI3K/Akt信号通路抑制剂Ly294002,则明显地减弱了H2S的神经细胞保护作用。结论 H2S可通过激活PI3K/Akt信号通路保护PC12细胞对抗化学性缺氧损伤。     

热休克蛋白90在硫化氢保护PC12细胞对抗化学性缺氧损伤中的作用

目的探讨热休克蛋白90(Hsp90)在硫化氢(H2S)保护PC12细胞对抗氯化钴(CoCl2)引起的化学性缺氧损伤中的作用。方法在PC12细胞建立H2S预处理对抗CoCl2诱导PC12细胞损伤的实验模型。应用细胞计数试剂盒8(CCK-8)检测细胞存活率;Hoechst 33258染色荧光显微镜照相术检测凋亡PC12细胞的形态学改变;应用碘化丙啶(PI)染色流式细胞术检测细胞凋亡率;免疫印迹法(Western blot)检测Hsp90的表达。结果H2S的供体400μmol·L-1硫氢化钠(NaHS)可上调PC12细胞Hsp90的表达,NaHS作用3h,Hsp90表达达最高峰,作用24h时表达恢复到基础水平;NaHS也能明显地增加CoCl2引起的Hsp90的表达上调。NaHS预处理能对抗CoCl2引起的PC12细胞损伤,提高细胞存活率,降低细胞凋亡率。Hsp90抑制剂17-丙烯胺基-17-去甲氧基格尔德霉素(17-AAG)可拮抗NaHS预处理对Hsp90表达的上调作用,并明显地减弱H2S诱导的适应性细胞保护作用。结论H2S能保护PC12细胞对抗CoCl2诱导的低氧损伤作用,诱导Hsp90表达上调可能是其细胞保护机制之一。     

IGF-1对6-OHDA诱导神经元氧化损伤的保护作用

目的 探讨胰岛素样生长因子-1（IGF-1）对6-羟基多巴胺（6-OHDA）诱导的PC12细胞氧化损伤的保护作用。方法 以25、50、100、150、200 μmol/L 的6-OHDA 处理PC12细胞,在12、24、48 h用MTT 法检测6-OHDA 对PC12细胞活性的影响,筛选最佳的实验浓度和观察时间。实验分为3组：对照组、6-OHDA组（150 μmol/L处理24 h）和IGF-1+6-OHDA组（IGF-1 100 nmol/L预处理2 h,后加入150 μmol/L 6-OHDA处理24 h）,MTT法检测各组细胞活性;免疫荧光染色法检测细胞活性氧（ROS）水平;Hoechst33342/PI双染法检测细胞凋亡。结果 随6-OHDA浓度的增加和作用时间的延长,PC12细胞的活性呈梯度降低,150 μmol/L 6-OHDA浓度和处理后24 h作为本研究的最佳的实验浓度和观察时间。与6-OHDA组比较,IGF-1+6-OHDA组PC12细胞活力增强、ROS水平下降、细胞凋亡减少。结论 IGF-1预处理能减少6-OHDA引起的PC12细胞氧化损伤及凋亡,增加细胞活性,为防治帕金森病提供了潜在的治疗策略。     

天麻素通过抑制细胞凋亡保护谷氨酸诱导的PC12细胞损伤

目的：研究天麻素（Gastrodin）对谷氨酸诱导的大鼠肾上腺嗜铬细胞瘤PC12细胞损伤的影响及可能机制。方法：以谷氨酸建立体外培养PC12细胞损伤模型并采用MTT比色法测定细胞存活率;AO/EB双染法经荧光显微镜观察细胞凋亡形态;采用流式细胞术检测细胞内活性氧含量以及Annexin V/PI染色后的细胞凋亡率;Western blot法检测细胞内Caspase-3蛋白表达。结果：天麻素可明显抑制谷氨酸诱导的PC12细胞凋亡,在0.1～10μmol/L剂量呈一定的量效关系;同时,天麻素可明显抑制谷氨酸引起的活性氧（ROS）的累积,降低谷氨酸诱导的活性Caspase-3蛋白的表达,降低PC12细胞的凋亡率,在0.1～10μmol/L剂量呈量效相关性。结论：在一定剂量范围内,天麻素对谷氨酸损伤的PC12细胞具有保护作用,其机制可能与减少ROS的生成,阻止氧化损伤的发生,抑制Caspase-3途径依赖的细胞凋亡相关。     

右美托咪定对抗化学性低氧引起的PC12细胞损伤

目的探讨α2肾上腺素受体激动剂右美托咪定能否保护PC12细胞对抗化学性低氧引起的损伤。方法应用化学性低氧模拟剂氯化钴(CoCl2)处理PC12细胞以建立化学性缺氧损伤模型。应用CCK-8比色法检测细胞存活率;Ho-chest 33258核染色法观察细胞凋亡的形态学和数量的改变;双氯荧光素(DCFH-DA)染色荧光显微镜检测细胞内的活性氧(ROS)水平;罗丹明123(Rh123)染色荧光显微镜检测线粒体膜电位(MMP)。结果在浓度为100～600μmol.L-1的范围内,右美托咪定浓度依赖性地对抗CoCl2引起的细胞毒性,使细胞存活率明显增加。400μmol.L-1右美托咪定能抑制CoCl2的致凋亡作用,使凋亡细胞数量减少。右美托咪定也能抑制CoCl2引起的ROS过度生成及MMP降低的作用。结论右美托咪定能保护PC12细胞对抗CoCl2诱导的损伤,此作用可能与其抑制ROS过度生成及保护MMP有关。     

Heat shock protein 90 mediates cytoprotection by H₂S against chemical hypoxia-induced injury in PC12 cells

1. Increasing evidence indicates that hydrogen sulphide (H₂S) may serve as an important biological cytoprotective agent. Heat shock protein (Hsp) 90 can attenuate stress‐induced injury. However, whether Hsp90 mediates the cytoprotective effect of H₂S against chemical hypoxia‐induced injury in PC12 cells is not known. 2. In the present study, CoCl₂ (a chemical hypoxia mimetic) was used to treat PC12 cells to create a model of chemical hypoxia. To explore the role of Hsp90 in the cytoprotection afforded by H₂S against chemical hypoxia‐induced injury, 2 μmol/L 17‐allylaminogeldanamycin (17‐AAG), a selective inhibitor of Hsp90, was administered for 30 min prior to preconditioning with 400 μmol/L NaHS, followed by chemical hypoxia. 3. Cobalt chloride reduced cell viability (by 52.7 ± 1.5%), increased PC12 cell apoptosis (by 42.1 ± 1.5%), induced reactive oxygen species (ROS) by 3.79% compared with control and induced the dissipation of mitochondrial membrane potential (MMP) by 2.56% compared with control. 4. Pretreatment of PC12 cells with 100–400 μmol/L sodium hydrosulphide (NaHS), an H₂S donor, for 3 h prior to exposure to 600 μmol/L CoCl₂ provided significant, concentration‐dependant protection to PC12 cells against CoCl₂‐induced cytotoxicity. Specifically, pretreatment of PC12 cells with 400 μmol/L NaHS decreased apoptosis to 16.77 ± 1.77% and blocked the CoCl₂‐induced increase in ROS production and loss of MMP. 5. At 400 μmol/L, NaHS upregulated Hsp90 in a time‐dependant manner (over the period 0–180 min). In addition to its effects on Hsp90 expression, NaHS pretreatment of PC12 cells augmented the overexpression of Hsp90 induced by 600 μmol/L CoCl₂ by 1.38‐fold (P < 0.01). 6. Treatment of PC12 cells with 2 μmol/L 17‐AAG for 30 min prior to NaHS pretreatment blocked the overexpression of Hsp90 induced by NaHS preconditioning, as evidenced by decreased cell viability (by 54.2 + 1.2%; P < 0.01), increased PC12 cell apoptosis (by 36.6 ± 1.2%; P < 0.01) and increasing ROS production. 7. The findings of the present study provide novel evidence that Hsp90 mediates H₂S‐induced neuroprotection against chemical hypoxia‐induced injury via anti‐oxidant and anti‐apoptotic effects.     

Effect of hydrogen sulphide on beta-amyloid-induced damage in PC12 cells

1. Hydrogen sulphide (H(2)S) is a well-known cytotoxic gas. Recently, H(2)S has been shown to protect neurons against oxidative stress caused by glutamate, peroxynitrite and HOCl. Considerably lower H(2)S levels have been reported in the brain of Alzheimer's disease (AD) patients with accumulation of beta-amyloid (A beta). 2. The aim of present study was to explore the cytoprotection by H(2)S against A beta(25-35)-induced apoptosis and the molecular mechanisms underlying this effect in PC12 cells. 3. Our findings indicated that A beta(25-35) significantly reduced cell viability and induced apoptosis of PC12 cells, along with dissipation of the mitochondrial membrane potential (MMP) and overproduction of reactive oxygen species (ROS). 4. Sodium hydrosulphide (NaHS), an H(2)S donor, protected PC12 cells against A beta(25-35)-induced cytotoxicity and apoptosis not only by reducing the loss of MMP, but also by attenuating the increase in intracellular ROS. 5. The results of the present study suggest that the cytoprotection by H(2)S is related to the preservation of MMP and attenuation of A beta(25-35)-induced intracellular ROS generation. These findings could significantly advance therapeutic approaches to the neurodegenerative diseases that are associated with oxidative stress, such as AD.     

Hydrogen sulphide protects H9c2 cells against chemical hypoxia‐induced injury

1. The aim of the present study was to investigate the effect of hydrogen sulphide (H₂S) on cobalt chloride (CoCl₂)‐induced injury in H9c2 embryonic rat cardiac cells. 2. After 36 h incubation in the presence of 600 μmol/L CoCl₂, reduced cell viability of H9c2 cells was observed, as well as the induction of apoptosis. In addition, CoCl₂ (600 μmol/L) enhanced the production of reactive oxygen species (ROS) and the expression of cleaved caspase 3, induced a loss of mitochondrial membrane potential (MMP) and decreased reduced glutathione (GSH) production. These results suggest that CoCl₂ induces similar responses to hypoxia/ischaemia. 3. Pretreatment of cells with 400 μmol/L NaHS (a H₂S donor) for 30 min prior to exposure to CoCl₂ (600 μmol/L) significantly protected H9c2 cells against CoCl₂‐induced injury. Specifically, increased cell viability and decreased apoptosis were observed. In addition, NaHS pretreatment blocked the CoCl₂‐induced increases in ROS production and cleaved caspase 3 expression, as well as the decreases in GSH production and loss of MMP. 4. Pretreatment of cells with 2000 μmol/L N‐acetylcysteine (NAC), a ROS scavenger, for 1 h prior to CoCl₂ exposure significantly protected H9c2 cells against CoCl₂‐induced injury, specifically enhancing cell viability, decreasing ROS production and preventing loss of MMP. 5. The findings of the present study suggest that H₂S protects H9c2 cells against CoCl₂‐induced injury by suppressing oxidative stress and caspase 3 activation.     

H_2O_2预处理对PC12细胞氧化应激损伤的适应性细胞保护作用

目的　探讨H2 O2 预处理对PC12细胞氧化应激损伤的适应性细胞保护作用及与脑源性神经营养因子 (brain de rivedneurotrophicfactor,BDNF)的关系。 方法　采用MTT法检测细胞活力 ,PI染色流式细胞术检测细胞凋亡 ,间接免疫荧光流式细胞术检测细胞BDNF的表达。结果　PC12细胞经 10 μmol·L-1H2 O2 预处理 90min后 ,2 0～ 6 0 μmol·L-1H2 O2 对PC12细胞生长的抑制程度明显下降 ,H2 O2 (2 0、30μmol·L-1)对PC12细胞凋亡的诱导作用明显受到抑制 ,BD NF的表达强度增强。结论　H2 O2 预处理对PC12细胞氧化应激损伤具有保护作用 ,其作用机制可能与增加脑源性神经营养因子表达有关