RCS变性大鼠感光细胞凋亡及其视网膜电图与caspase-9时空表达的关系研究

目的：研究caspase-9在英国皇家外科学院(RCS)变性大鼠视网膜的时空表达状况与其视网膜电图(ERG)以及感光细胞凋亡的关系，以探讨caspase-9在感光细胞凋亡中的作用。 方法： 不同日龄RCS变性大鼠，检查ERG后处死取视网膜行caspase-9的免疫组化、荧光活力分析、Western blotting及凋亡TUNEL检测。 结果： 15及20 d变性大鼠ERG b波潜伏期分别为(58.60±3.42)ms、(56.45±1.08)ms，振幅分别为(109.07±14.50)mV、(109.00±7.35)mV，两组间无显著性差异，25和30d组接近熄灭型。TUNEL阳性细胞只在变性大鼠的外颗粒层表达，25 d最明显。25 d后的变性大鼠感光细胞内节可见明显caspase-9阳性表达，其余各组未见表达。20 d caspase-9表现出最大活力［(10.98±0.13)nmol·g-1·min-1］。Western blotting分析显示caspase-9裂解条带在20 d时最明显，15 d组和对照组不表达。 结论： caspase-9的表达与视网膜感光细胞凋亡、视功能丧失存在时空一致性。     

RCS大鼠视网膜感光细胞的凋亡

为研究遗传性视网膜变性中感光细胞组织结构的时程变化及调亡，对ＲＣＳ大鼠脑ＳＤ大鼠视网膜进行光镜观察和凋亡细胞ＴＵＮＥＬ检测。结果表明，与同龄ＳＤ大鼠相比，ＲＣＳ大鼠视网膜感光细胞从出生后１５ｄ开始，出现外节膜盘堆积；２０ｄ时，内节排列紊乱，消失，３０ｄ，细胞核固缩，细胞消失，到出生后６０ｄ，仅少许感光细胞保留；１００ｄ，几乎所有感光细胞消失。ＴＵＮＥＬ检测，从出生后２５ｄ开始，ＲＣＳ大鼠视网膜有Ｔ     

RCS大鼠感光细胞凋亡与 Fas蛋白表达

为了探讨遗传性视网膜变性时感光细胞凋亡及其基因调控机制 ,本研究对出生后 9、15、2 0、2 5、3 0、3 5、40、60 d的 RCS大鼠及同龄 SD大鼠各 4只的视网膜进行了 TU NEL 凋亡检测及 Fas蛋白免疫组织化学反应。结果表明 ,出生后 2 5～ 40 d,RCS大鼠视网膜外核层可见 TUNEL阳性的感光细胞核 ,TUNEL阳性细胞数到 3 5 d达高峰 ( P<0 .0 5 )。Fas蛋白免疫组织化学检测发现 ,RCS大鼠视网膜内核层在 15～ 40 d可见 Fas免疫阳性细胞 ,阳性细胞数以 2 5 d为最多 ( P<0 .0 5 ) ;外核层在 2 5 d也可见Fas蛋白免疫阳性反应 ,一直持续到 40 d;节细胞层在 15～ 40 d可见 Fas蛋白表达。到 60 d时则各层又都不见明显的 Fas蛋白阳性反应。本研究结果提示 ,在 RCS大鼠视网膜变性过程中 ,感光细胞发生凋亡 ,Fas蛋白高表达可能与感光细胞的凋亡有关     

遗传性视网膜变性rd小鼠及其感光细胞凋亡研究

目的 研究遗传性视网膜变性rd小鼠感光细胞层的发育变化及细胞凋亡。方法 对出生后5d到40d的rd小鼠及对照小鼠视网膜感光细胞层进行光镜及超微结构观察、TUNEL法检测及形态计量学分析。结果 与同龄对照鼠相比,rd小鼠出生后第10d视网膜开始变性,尔后1周内感光细胞迅速减少,第18d时只残留一层视椎细胞。rd小鼠出生后第10d感光细胞层开始出现TUNEL染色阳性细胞,第14d及16d达到高峰。电镜下变性高峰期rd小鼠视网膜感光细胞层可见大量浓缩核、染色质边聚及凋亡小体。结论 rd小鼠视网膜感光细胞在发育过程中变性,并通过凋亡的方式死亡。     

半胱天冬酶天然抑制剂与细胞凋亡

在生物体内,细胞增殖与细胞凋亡总是处于动态平衡状态,从而保证了多细胞生物维系其结构稳定和内环境功能平衡及正常生长发育。正常的细胞凋亡可清除体内衰老的、磨损的或已完成功能的细胞,如胚胎细胞、胸腺细胞等;并能清除具有潜在危险的畸变细胞,如自身反应性淋巴细胞、突变细     

臭灵丹中黄酮类化合物对人喉癌细胞Hep-2凋亡的影响及机制

目的:探讨中药臭灵丹中黄酮类化合物诱导人喉癌细胞Hep-2凋亡的机制。方法:MTT法检测分离自臭灵丹的黄酮类化合物3,5-二羟基-6,7,3',4'-四甲氧基黄酮(HTMF)对2种正常细胞的毒性和对3种肿瘤细胞株的增殖抑制作用;采用流式细胞仪检测化合物对Hep-2细胞凋亡率的影响;Western blotting法检测凋亡蛋白caspase-3和caspase-9的变化。结果:HTMF显著抑制Hep-2细胞的增殖并呈浓度、时间双重依赖性关系,但对正常细胞Vero和EVC304的毒性较小,对A549和HepG2细胞抑制作用小。流式细胞仪检测结果显示HTMF对Hep-2细胞有促凋亡作用并呈明显的量效、时效关系。Western blotting结果显示HTMF可诱导Hep-2细胞中caspase-3和caspase-9蛋白的活化,并呈时间依赖性关系。结论:HTMF对人喉癌细胞Hep-2的生长有显著的抑制作用,其机制可能通过激活caspase-9进而活化caspase-3诱导Hep-2细胞凋亡。     

Caspase-3在大鼠中枢神经系统的表达研究

目的研究caspase-3在大鼠中枢神经系统的表达及其意义。方法用western-blot方法对出生1天和3个月SD大鼠的大脑皮质、中脑和小脑组织的caspase-3进行半定量测定。结果出生1天大鼠脑的caspase-3表达较高,出生3个月大鼠脑的caspase-3表达较低。结论caspase-3在中枢神经系统的发育成熟过程中对神经元的凋亡起着关键性作用。     

Caspase-3抑制剂抑制长春碱诱导的人乳腺癌细胞凋亡及IκΒ-α降解

目的： 本实验通过阻断caspase-3途径,观察长春碱诱导的肿瘤细胞凋亡及胞浆内IκΒ-α蛋白降解的影响,以探索长春碱诱导肿瘤细胞凋亡的信号转导途径。方法: 用二甲基亚砜对照、100 μmol/L caspase-3抑制剂(DEVD-CHO)预处理乳腺癌Bcap37细胞3 h后,加入不同浓度的长春碱,以MTT法检测肿瘤细胞增殖能力,以细胞DNA片段分析及PI染色法检测肿瘤细胞凋亡,以蛋白免疫印迹法检测pro-caspase-3和IκΒ-α蛋白的变化。结果: 蛋白免疫印迹法证实长春碱可诱导pro-caspase-3蛋白的降解。经MTT法、DNA凋亡梯状条带法及流式细胞仪PI染色法证实,DEVD-CHO能减弱由长春碱所诱导的肿瘤细胞凋亡。两组的IC50分别为56.8 μmol/L和87.4 μmol/L。蛋白免疫印迹实验表明,DEVD-CHO能抑制由长春碱所诱导的IκΒ-α蛋白磷酸化降解。结论: 在长春碱诱导肿瘤细胞凋亡过程中,NF-κΒ/IκΒ信号转导途径起着重要作用,caspase-3途径参与调节。阻断该途径将减弱长春碱所诱导的肿瘤细胞凋亡和IκΒ-α磷酸化降解。     

Survivin 抑制剂YM155 对甲状腺癌B-CPAP 细胞凋亡的影响及机制研究

目的:探讨人生存素(Survivin)抑制剂YM155{4,9-二氢-1-(2-甲氧基乙基)-2-甲基-4,9-二氧代鄄3-(2-吡嗪甲基)-1H-萘并[2,3-d]咪唑鎓溴化物}对甲状腺癌B-CPAP 细胞活力和凋亡的影响以及凋亡相关酶半胱氨酸蛋白酶-3(Cysteinyl aspartate specific proteinase-3,Caspase-3),半胱氨酸蛋白酶鄄8(Cysteinyl aspartate specific proteinase-8,Caspase-8)和半胱氨酸蛋白酶-9(Cysteinyl aspartate specific proteinase-9,Caspase-9)表达的变化,探讨其诱导B-CPAP 细胞凋亡的可能机制。方法:体外培养B-CPAP 细胞,分别以0、0.5、1、2、4、8 nmol/ L 浓度的YM155 进行处理24 、48 和72 h,采用CCK-8 检测试剂盒检测YM155对B-CPAP 细胞活力的抑制作用;B-CPAP 细胞随机分为4 组:分别以0、1、2 nmol/ L YM155 和5 μmol/ L 顺铂(Cisplatin,阳性对照组)处理24 h。分别采用TUNEL 染色和流式细胞仪AnnexinV-FITC/ PI 法检测凋亡的情况;采用RT-PCR 检测Survivin mRNA 的表达;采用比色法和Western blot 检测Survivin 和Caspase-3、Caspase-8、Caspase-9 的活性和表达。结果:与0 nmol/ L 组比较,YM155 对B-CPAP 细胞活力具有明显抑制作用,并诱导B-CPAP 细胞凋亡(P<0.05 或P<0.01);与阴性对照组比较,YM155 显著降低B-CPAP 细胞Survivin 的表达,并上调Caspase-3、Caspase-8、Caspase-9 的表达(P<0.05 或P<0.01)。结论:YM155 对B-CPAP 细胞活力具有抑制作用,诱导其凋亡,其机制可能与上调Caspase-3、Caspase-8 和Caspase-9 表达有关。     

Caspase-3抑制剂抑制长春碱诱导的人乳腺癌细胞凋亡及IκB-α降解

目的：本实验通过阻断caspase-3途径,观察长春碱诱导的肿瘤细胞凋亡及胞浆内IκB-α蛋白降解的影响,以探索长春碱诱导肿瘤细胞凋亡的信号转导途径。方法：用二甲基亚砜对照、100μmol／Lcaspase-3抑制剂（DEVD—CHO）预处理乳腺癌Bcap37细胞3h后,加入不同浓度的长春碱,以MTT法检测肿瘤细胞增殖能力,以细胞DNA片段分析及PI染色法检测肿瘤细胞凋亡,以蛋白免疫印迹法检测pro—caspase-3和IKB—α蛋白的变化。结果：蛋白免疫印迹法证实长春碱可诱导pro—caspase-3蛋白的降解。经MTY法、DNA凋亡梯状条带法及流式细胞仪PI染色法证实,DEVD—CHO能减弱由长春碱所诱导的肿瘤细胞凋亡。两组的IC,。分别为56．8μmol／L和87．4μmol／L。蛋白免疫印迹实验表明,DEVD—CHO能抑制由长春碱所诱导的IκB-仪蛋白磷酸化降解。结论：在长春碱诱导肿瘤细胞凋亡过程中,NF—κB／IκB信号转导途径起着重要作用,caspase-3途径参与调节。阻断该途径将减弱长春碱所诱导的肿瘤细胞凋亡和IκB一α磷酸化降解。     

大鼠脑缺血再灌流后神经细胞凋亡与caspase-3和caspase-9基因表达

目的：探讨大鼠局灶性脑缺血再灌流后神经细胞凋亡及其与caspase-3和caspase-9基因表达的关系。方法：应用原位末端标记和原位杂交技术分别观察细胞凋亡与caspase-3mRNA和caspase-9mRNA表达。结果：脑缺血再灌流后，凋亡神经细胞主要分布于缺血半影区，随着时间的延长凋亡细胞数逐渐增加，至24h达高峰。在缺血半影区，再灌流后神经细胞caspase-3mRNA和caspase-9mRNA表达逐渐增强，到24h阳性细胞数目最多，COD值最高，而缺血中心区两基因均弱表达。结论：脑缺血再灌流后神经细胞凋亡是一个动态的渐进过程。caspase-3和caspase-9基因表达在介导细胞凋亡过程中起重要作用。     

Involvement of caspase-8, -9, and -3 in high glucose-induced apoptosis in PC12 cells

Hyperglycemia, which occurs under the diabetic condition, is widely recognized as the causal link between diabetes and its serious complications. Diabetic neuropathies, which are among the most frequent complications of diabetes, affect sensory, motor, and autonomic nerves. The exact molecular mechanisms of high glucose-induced toxicity on neuronal cells, is still unclear. We previously reported that high glucose can induce apoptosis in PC12 cells, as evidenced by DNA fragmentation and high Bax/Bcl-2 ratio. The present study examined the involvement of caspase-3, the executioner, and two initiators of apoptosis, caspase-8 and caspase-9, during high glucose-induced apoptosis in PC12 cells, a neuronal cell line. Cells were exposed to high glucose with or without z-VAD-fmk, a pan-caspase inhibitor. Cell viability was measured by MTT assay. Caspase activity was determined spectrophotometrically using enzyme specific substrates. To correlate and confirm the caspase activity with changes in protein expression, procaspase-8, -9, and -3 were evaluated by Western blot analysis. The DNA-fragmentation was determined by DNA ladder using gel electrophoresis. The PC12 cell viability on high glucose exposure was decreased compared to controls, which was reversed by z-VAD-fmk. The activities of caspase-8, -9, and -3 were significantly increased in treated cells compared to controls. Moreover, high glucose exposure induced a significant decrease in protein levels of procaspases, indicating conversion of pro-form into the mature caspases. Finally, DNA fragmentation (Ladder) was shown in treated cells by high glucose. Based on the current data, it could be concluded that high glucose-induced apoptosis in PC12 cells is mediated, in part, by activation of caspase-8, -9, and -3 dependent pathways.     

Immune clearance gastric carcinoma cells in ascites by activating caspase-9-induced apoptosis

Floating gastric adenocarcinoma cells in ascitic fluid are the main cause of peritoneal dissemination. Activation of apoptosis is an important mechanism by which tumor cells are eliminated by the immune surveillance system. Hence, we examined caspase-9 expression and the apoptosis in gastric adenocarcinoma cells in ascitic fluid using immunohistochemistry, real-time polymerase chain reaction and in situ cell death detection kits, flow cytometry. The results revealed strong expression of caspase-9 in 58.49% (31/53) malignant cells and a relatively weak expression of caspase-9 in 41.51% (22/53) malignant cells. The proportion of apoptotic cells in 31 malignant cases with strong caspase-9 expression (35.14 ± 3.42)% was significantly higher than that in 22 malignant cases with relatively weak caspase-9 expression (17.29 ± 7.62)% or in mesothelial cells (10.76 ± 4.21%; p < 0.05). Kaplan-Meier survival curves demonstrated that the patients with low caspase-9 expression showed significantly shorter survival (p < 0.05) than those with high caspase-9 expression. These findings suggest that immune clearance gastric carcinoma cells in ascites activated by caspase-9 helped to improve the prognosis of patients with gastric cancer.     

乳腺癌中caspase-3和caspase-9的表达及其意义

目的探讨caspase-3和caspase-9在乳腺癌发生、发展中的作用。方法采用免疫组化SP法和原位杂交(ISH)技术检测80例乳腺浸润性导管癌(invasive duct carcinoma,IDC)、23例导管内癌(ductal carcinoma in situ,DCIS)、37例增生症和9例癌旁组织中caspase-3、caspase-9 mRNA和蛋白的表达。结果 caspase-3 mRNA在各组中的表达差异无统计学意义(P>0.05)。caspase-3蛋白在IDC、DCIS、增生症中的表达均高于癌旁组织(P<0.05),在IDC、DCIS中的表达均高于增生症组(P<0.05)。caspase-9 mRNA和蛋白在IDC、DCIS、增生症中的表达均低于癌旁组织(P<0.05),IDC、DCIS中的表达均低于增生症组(P<0.05)。caspase-3、caspase-9蛋白在IDC与DCIS中的表达差异均无统计学意义(P>0.05)。caspase-3蛋白与mRNA在DCIS和增生症中的表达呈正相关(r=0.429,r=0.563,P<0.05)。caspase-9 mRNA与蛋白在各组中的表达均存在相关性(r=0.94,r=0.414,r=0.391,r=0.827,P<0.05)。caspase-3、caspase-9 mRNA和蛋白的表达与肿瘤大小等临床病理参数无相关性(P>0.05)。结论 caspase-3和caspase-9均参与乳腺导管癌的发生、发展。caspase-9蛋白表达降低,而caspase-3表达增高在乳腺癌的发生、发展过程中较常见;caspase-9表达降低可能与乳腺组织恶性转化有关。     

Expression of phosphorylated caspase-9 in gastric carcinomas

Alterations of caspases, the main executioners of apoptosis, have been described in human cancers. Caspase-9 plays a crucial role in the initiation phase of the intrinsic apoptosis pathway. Caspase-9 is phosphorylated at Thr125 through the mitogen-activated protein kinase (MAPK) pathway, and this phosphorylation is associated with inhibition of caspase-9 activation. The aim of this study was to explore whether phosphorylated caspase-9 (p-caspase-9) expression could be a characteristic of gastric carcinomas. We analyzed expression of p-caspase-9 protein in 60 gastric adenocarcinomas by immunohistochemistry using a tissue microarray approach. p-caspase-9 was detected in 33 of the 60 carcinomas (55%). Both early and advanced gastric carcinomas expressed p-caspase-9. There was no significant association of p-caspase-9 expression with clinocopathological characteristics, including invasion, metastasis and stage. In contrast to gastric cancer cells, epithelial cells in normal gastric mucosa showed no or only weak expression of p-caspase-9. Taken together, these results indicate that caspase-9 is frequently phosphorylated in gastric carcinomas, and that the phosphorylation of caspase-9 might be an inhibitory mechanism of caspase-9-mediated apoptosis in gastric carcinomas. Increased expression of p-caspase-9 in malignant gastric epithelial cells compared to normal mucosal epithelial cells suggests that p-caspase-9 expression might play a role in gastric carcinoma development.     

线粒体凋亡路径参与创伤后应激障碍大鼠海马神经元凋亡的调控

目的观察Caspase-9、Caspase-3和细胞色素C(CytC)在创伤后应激障碍(PTSD)大鼠海马神经元中的表达及相互关系,探讨PTSD大鼠海马神经元凋亡的信号转导机制。方法成年雄性Wistar大鼠60只,采用国际认定的无连续单一应激(SPS)方法刺激大鼠建立PTSD大鼠模型,取SPS刺激后1d、4d、7d、14d、28d组和正常对照组。应用免疫组织化学、免疫荧光和免疫印迹法检测Caspase-9、Caspase-3和CytC蛋白的表达。结果免疫组织化学和免疫荧光结果显示,CytC蛋白于SPS刺激后4d在海马神经元胞质内的表达达到高峰,并维持较高水平,SPS刺激后7d逐渐下降。SPS刺激后,Caspase-9和Caspase-3阳性表达增强,均于SPS刺激后7d达到高峰。免疫印迹结果显示,与正常对照组相比,模型组海马胞质内CytC蛋白水平明显上调,于SPS刺激后4d达到较高水平。而SPS刺激后线粒体中CytC蛋白水平则显著下降。在正常对照组,无Caspase-9和Caspase-3活性片段;在模型组,出现Caspase-9和Caspase-3活性片段,两者均于SPS刺激后7d达到高峰,14d开始下调。结论神经元凋亡可能是导致PTSD大鼠海马萎缩的重要机制之一;线粒体通路的激活参与了PTSD大鼠海马神经元凋亡的调控。     

Altered apoptosis of inflammatory neutrophils in MMP-9-deficient mice is due to lower expression and activity of caspase-3

Matrix metalloproteinase 9 (MMP-9) is a Zn²⁺-dependent endopeptidase that degrades some of the components of basement membranes and extracellular matrix and thus participates in leukocyte infiltration during inflammation. In a model of zymosan peritonitis, neutrophil infiltration in MMP-deficient (MMP-9^−/−) mice was significantly weaker at the time of their maximal influx in wild-type mice (6 h). However, during the late stages of peritonitis (24 h) an extended accumulation of neutrophils was observed in MMP-9^−/− versus the wild-type mice. Recently, we reported that the ratio of apoptosis of inflammatory leukocytes is impaired in MMP-9^−/− mice during late peritonitis and the process depends on COX-1-driven PGE₂. Here we scrutinized the alterations in apoptotic mechanisms by comparisons between MMP-9^−/− and the wild-type mice. Altered apoptosis occurred only during late (24 h) peritonitis and concerned only neutrophils, and not macrophages, mast cells or lymphocytes. Furthermore, expression and activity of caspases was altered in MMP-9^−/− animals, delayed for caspase-8 and -9, and decreased in the case of caspase-3. Also the expression of Bax/Bcl-2 proteins was changed in MMP-9^−/− mice. These changes, and in particular the impaired neutrophil apoptosis and weaker caspase-3 activity, were restored by the selective COX-1 inhibition. We conclude that in mice lacking MMP-9 the enhanced COX-1-PGE₂ decreases caspase-3 expression and activity leading to impaired apoptosis of inflammatory neutrophils resulting in abnormal accumulation of the cells at the inflammatory focus. The data also reinforce the notion that MMP-9 is a key enzyme in neutrophil biology.     

Caspase-9和caspase-3在创伤后应激障碍大鼠海马神经元的表达及意义

目的:探讨caspase-9和caspase-3在创伤后应激障碍(PTSD)大鼠海马神经元中的表达及意义.方法:采用国际认定的无连续单一应激(SPS)方法刺激大鼠建立PTSD大鼠模型,取SPS刺激后1、4、7、14、28 d组和正常对照组.应用免疫组织化学、免疫荧光双标、激光共聚焦显微镜技术和免疫印迹法检测caspase-9和caspase-3蛋白的表达.结果:与正常对照组相比,caspase-9活性于SPS刺激后1 d升高,SPS刺激后7 d再次上调并达到高峰,之后逐渐下降.Caspase-3活性于SPS刺激后7 d达到高峰,之后逐渐下降.结论:caspase-9和caspase-3共同参与了PTSD大鼠海马神经元凋亡的调控.     

Phosphorylation of caspase-9 in the cytosolic fraction of the cerebral cortex of newborn piglets following hypoxia

We have previously shown that hypoxia leads to increased expression and increased activity of caspase-9 in the cerebral cortex of newborn piglets. Previous studies have demonstrated the importance of caspase-9 in the initiation of the apoptotic cascade, however, the mechanism of caspase-9 activation is not well understood. Experiments were conducted on newborn piglets 2-3 days of age that were anesthetized and mechanically ventilated. Hypoxia was induced by lowering the FiO(2) to 0.05-0.07 x 1h, and was confirmed biochemically by demonstrating decreased levels of ATP and PCr in the hypoxic groups in comparison with the normoxic group. The ATP level was 1.99+/-0.66 in the hypoxic group versus 4.10+/-0.19 in the normoxic group, P<0.05, and the PCr value was 0.68+/-0.14 in the hypoxic group, compared to 2.98+/-0.39 in the normoxic group, P<0.05. The cytosol of the neuronal nuclei from the cerebral cortex was probed with anti-phosphorylated Ser(196) caspase-9 antibody, using Western blot analysis. Protein bands were analyzed using image densitometry. In both the hypoxic and normoxic samples, protein bands were demonstrated just above the 50 kDa marker. Phosphorylated caspase-9 expression in OD x mm(2) was 43.85+/-8.4 in the normoxic group and 67.6+/-9.88 in the hypoxic group, P<0.05. The results of this study demonstrate that caspase-9, a key protein in hypoxia induced apoptosis, is phosphorylated at the Ser(196) site during hypoxia. The results demonstrate that hypoxia results in a post-translational modification of caspase-9 at Ser(196), which may alter the activity of caspase-9 in the hypoxic newborn brain.