Caspase-9抑制剂对RCS大鼠感光细胞凋亡抑制作用的研究

目的：采用Z-LEHD-FMK进行体内实验，观察caspase-9抑制剂对RCS大鼠感光细胞凋亡的抑制作用。方法：32只 18 d RCS大鼠随机分4组，检查ERG后随机选择一眼为实验眼给予玻璃体内注射Z-LEHD-FMK 4 μg，对侧眼给予4 μg 2%DMSO作对照。各组分别在术后2 d、7 d、12 d、17 d行ERG检查，然后摘取双眼球，石蜡切片行HE染色及感光细胞凋亡的TUNEL检测，透射电镜观察视网膜超微结构。结果：实验眼注药后 7 d ERG b波振幅达到最大(137.35±7.41)mV，17 d时b波振幅为(57.91±9.27)mV，对照眼7 d及以后各组ERG接近熄灭型；实验眼注药后12 d视网膜外颗粒层才开始出现凋亡阳性细胞，17 d更明显，对照眼强荧光的凋亡阳性细胞在术后7 d已经很明显；光镜下注药后17 d实验眼感光细胞外颗粒层细胞数尚保持有7-8层，对照眼仅余下2-4层细胞，视网膜厚度变薄；透射电镜下实验眼注药后17 d可见部分感光细胞胞核、核仁固缩，对照眼从术后 7 d 开始见感光细胞呈现凋亡改变。结论：Z-LEHD-FMK能够延缓RCS大鼠感光细胞凋亡，合适的caspases抑制剂在适宜的时机应用对视网膜感光细胞凋亡具有一定的抑制作用。     

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。     

慢性酒精中毒大鼠海马神经元凋亡及caspase-8、AIF的表达升高

目的　观察慢性酒精中毒大鼠海马神经元凋亡及caspase-8、AIF蛋白表达情况,探讨慢性酒精中毒脑损伤可能的发病机制。方法　清洁级8周龄雄性SD大鼠45只,随机分为对照组和酒精组,采用逐步增加浓度自由饮方法建立慢性酒精中毒大鼠动物模型。应用Morris水迷宫检测大鼠学习记忆功能,采用HE染色法观察海马神经元病理形态学改变,TUNEL法、免疫组化法检测凋亡神经元数量及caspase-8、AIF蛋白的表达。结果　酒精组可见海马神经元数目缺失及细胞变性和损伤,其凋亡神经元数和caspase-8、AIF蛋白表达阳性细胞数均高于对照组（p<0.01）。结论　慢性酒精中毒大鼠海马存在明显神经元凋亡,伴有caspase-8、AIF蛋白表达增加,通过胱冬酶(caspase)依赖性和非依赖性两种通路发生细胞凋亡可能是其病理基础之一。     

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     

Fas/FasL介导的caspase-3活化与急性胰腺炎腺泡细胞凋亡的关系

目的： 研究凋亡调控基因及蛋白Fas、FasL和caspase-3在大鼠急性胰腺炎（AP）组织中的表达及其相互关系。方法：经胰胆管逆行注射不同浓度的牛磺胆酸钠建立不同炎症程度的AP模型,采用RT-PCR、Western blotting技术检测大鼠胰腺炎组织Fas、FasL和caspase-3蛋白及mRNA的表达, TUNEL法检测胰腺炎组织腺泡细胞凋亡。结果：在正常胰腺组织内即可见Fas、FasL、caspase-3蛋白和mRNA的表达;建立AP模型后,随胰腺炎症程度的加重,Fas、FasL、caspase-3蛋白和mRNA的表达逐渐下降,腺泡细胞凋亡率亦逐渐下降,且caspase-3 表达水平在各个组间的变化趋势与Fas/FasL系统的变化趋势相一致。结论：Fas/FasL系统介导的凋亡途径参与了急性胰腺炎腺泡细胞凋亡的调节。     

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。     

X连锁凋亡抑制蛋白和线粒体第二激活因子在锰诱导大鼠生精细胞凋亡蛋白酶表达中的调节作用

目的:研究氯化锰导致的大鼠生精细胞半胱氨酸天冬氨酸蛋白酶-9(caspase-9)及凋亡蛋白酶活化因子-1(Apaf-1)表达中X连锁凋亡抑制蛋白(XIAP)和线粒体第二激活因子(Smac)的调节机制,探讨锰导致的雄性不育机制。方法:雄性SD大鼠随机分为对照组、低剂量(15 mg/kg MnCl_2)和高剂量(30 mg/kg MnCl_2)组,腹腔注射MnCl_2 4周和6周,免疫组织化学检测生精细胞caspase-9、Apaf-1、XIAP和Smac表达。结果:与对照组相比较,各组生精细胞caspase-9、Apaf-1和Smac表达均显著升高,XIAP表达降低。同时间的高剂量组与低剂量组比较,同剂量的6周组与4周组比较,生精细胞caspase-9、Apaf-1和Smac表达均显著升高,XIAP表达降低。各组caspase-9与Apaf-1表达呈正相关,XIAP与Smac表达呈负相关。结论:锰可促进生精细胞caspase-9、Apaf-1和Smac表达,抑制XIAP表达,导致细胞凋亡,产生雄性生殖毒性效应。     

蛋白酶体抑制剂MG132诱导caspase-8依赖的骨肉瘤细胞凋亡机制研究

目的：探讨蛋白酶体抑制剂Z-LLL-CHO(MG132)对人骨肉瘤细胞MG-63的作用以及可能作用机制。方法:将不同浓度的MG132作用于骨肉瘤细胞MG-63，采用显微镜观察形态改变、电镜观察细胞超微结构、MTT检测细胞增殖活力、琼脂糖凝胶电泳检测细胞凋亡、流式细胞仪分析细胞凋亡率以及细胞周期改变、RT-PCR检测基因转录、Western blotting检测蛋白表达水平。 结果:MG132能有效诱导人骨肉瘤细胞系MG-63细胞周期在G₂-M期的停滞，并引起MG-63的凋亡，出现凋亡的典型形态学改变，同时出现p27kip1蛋白的积累，caspase-8活化蛋白表达增加，Bax∶Bcl-2蛋白含量比例的增高，而对正常的人二倍体成纤维细胞，MG132并未表现诱导其凋亡的活性。结论:MG132引起的人骨肉瘤细胞MG-63的凋亡也许是与caspase-8、p27kip1和Bcl-2蛋白相关的。     

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。     

Caspase 9 is decreased in psoriatic epidermis

Psoriasis is a proliferative and inflammatory disease of the skin. Caspase 9 is responsible for initiating the caspase activation cascade during apoptosis. Apoptosis is a physiological mechanism of homeostasis and development, and caspases are the executioners of apoptosis. This study reports the immunohistochemical localisation of caspase 9 in psoriatic skin and compares it with that seen in normal, healthy control skin. Skin biopsy specimens of lesions were obtained from 15 patients with plaque type psoriasis vulgaris. The specimens were labelled immunohistochemically for binding of an anti-caspase 9 primary antibody. Biopsies of healthy skin from 10 age-matched and sex-matched healthy control individuals were also analysed. The caspase 9 positive cell fraction was calculated for both epidermal and dermal cells in psoriatic lesions and healthy control skin. Counts of caspase 9 positive cells from the epidermis of psoriatic skin lesions were significantly lower than those seen in healthy skin (p<0.05). The caspase 9 immunolabelled perivascular cell counts in the dermis were not statistically significantly different in psoriatic lesions versus normal skin (p>0.05). Psoriatic epidermis contains little of the apoptotic marker, caspase 9. The results of this study are indicative of decreased apoptosis in psoriatic epidermis, and no change in the perivascular area in psoriatic lesions. These findings support the idea that decreased apoptosis is seen in psoriatic epidermal cells. Greater understanding of the nature of the disease may open new avenues for further therapeutic modalities.     

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.     

小脑颗粒神经元细胞凋亡中caspase-8基因变化与二乙酰吗啡的影响

背景：半胱-天冬氨酸蛋白酶8(Caspase-8)是细胞凋亡过程起始的重要因子,二乙酰吗啡可致神经元细胞凋亡,其与二乙酰吗啡致小脑颗粒神经元细胞凋亡之间关系尚未见报道。 目的：验证二乙酰吗啡诱导小脑颗粒神经元细胞凋亡与caspase-8基因表达情况,明确caspase-8参与二乙酰吗啡致神经元凋亡过程。 方法：取出生7 d SD大鼠小脑颗粒神经元细胞进行体外培养,第7天后,以不同质量浓度的二乙酰吗啡(10,40,80,100,120 mg/L)和C-jun氨基末端激酶通路特异性抑制剂SP600125作用小脑颗粒神经元细胞24 h,并分对照组(0 mg/L二乙酰吗啡),80 mg/L二乙酰吗啡组,二乙酰吗啡+SP 600125组;采用Hoechst 33258 荧光染色观察细胞形态学改变,流式细胞仪测细胞凋亡率,免疫荧光、RT-PCR及Western Blotting检测caspase-8 mRNA和蛋白表达情况。 结果与结论：①施加不同质量浓度二乙酰吗啡致神经元细胞凋亡,凋亡细胞出现透亮深蓝色的凋亡小体,细胞核呈现固缩、凝聚及断裂,随给药浓度增加细胞凋亡率呈现升高趋势(P < 0.05)。②与对照组相比,在80 mg/L二乙酰吗啡干预时caspase-8 mRNA和蛋白表达明显明显表达(P < 0.05);caspase-8 mRNA随给药浓度增加呈现升高趋势(P < 0.05),二乙酰吗啡+SP600125组中caspase-8 mRNA和蛋白较80 mg/L二乙酰吗啡组明显下调(P < 0.05)。结果提示caspase-8参与二乙酰吗啡致小脑颗粒神经元细胞凋亡过程,同时也是C-jun氨基末端激酶信号通路中的重要候选促凋亡因子。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接：     

Mutational analysis of proapoptotic caspase-9 gene in common human carcinomas

Mounting evidence indicates that deregulation of apoptosis is involved in the mechanisms of cancer development. Caspase-9 plays a crucial role in the initiation phase of the intrinsic apoptosis pathway. To explore the possibility that the genetic alterations of caspase-9 might be involved in the development of human cancers, we analyzed the entire coding region and all splice sites of the human caspase-9 gene for the detection of somatic mutations in a series of 353 cancers, including 180 gastric, 104 colorectal and 69 lung adenocarcinomas. Overall, we detected three somatic mutations of caspase-9, but all of the mutations were silent mutations. The mutations were observed in 2 of 104 colorectal carcinomas and 1 of 180 gastric carcinomas. These data indicate that the caspase-9 gene is rarely mutated in gastric, colorectal and lung adenocarcinomas, and suggest that caspase-9 gene mutation may not contribute to the pathogenesis of these cancers.     

The equine arteritis virus induces apoptosis via caspase-8 and mitochondria-dependent caspase-9 activation

We have previously showed that equine arteritis virus (EAV), an arterivirus, induces apoptosis in vitro. To determine the caspase activation pathways involved in EAV-induced apoptosis, target cells were treated with peptide inhibitors of apoptosis Z-VAD-FMK (pan-caspase inhibitor), Z-IETD-FMK (caspase-8-specific inhibitor) or Z-LEHD-FMK (caspase-9-specific inhibitor) 4 h prior to infection with the EAV T1329 Canadian isolate. Significant inhibition of apoptosis was obtained with all peptide inhibitors used. Furthermore, apoptosis was inhibited in cells expressing the R1 subunit of herpes simplex virus type 2 ribonucleotide reductase (HSV2-R1) or hsp70, two proteins which are known to inhibit apoptosis associated with caspase-8 activation and cytochrome c release-dependent caspase-9 activation, respectively. Given the activation of Bid and the translocation of cytochrome c within the cytoplasm, the overall results indicate that EAV induces apoptosis initiated by caspase-8 activation and subsequent mitochondria-dependent caspase-9 activation.     

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.     

Activation of retinal stem cells in the proliferating marginal region of RCS rats during development of retinitis pigmentosa

Retinal stem cells (RSCs) have been demonstrated at the proliferating marginal regions from the pars plana of ciliary body to the ciliary marginal zone (CMZ) in adult lower vertebrates and mammals. Investigations in the lower vertebrates have provided some evidence that RSCs can proliferate following retinal damage; however, the evidence that this occurs in mammals is not clear. In this study, we explored RSCs proliferation potential of adult mammalian in proliferating marginal regions of Royal College of Surgeons (RCS) rats, an animal model for retinitis pigmentosa (RP). The proliferation was evaluated using BrdU labeling, and Chx-10 as markers to discern progenitor cell of CMZ in Long-Evan's and RCS rats at different postnatal day (PND) after eye opening. We found that few Chx-10 and BrdU labeled cells in the proliferating marginal regions of Long-Evan's rats, which significantly increased in RCS rats at PND30 and PND60. Consistent with this, Chx-10/Vimentin double staining cells in the center retina of RCS rats increased significantly at PND30 after eye opening. In addition, mRNA expression of Shh, Ptch1 and Smo was up-regulated in RCS rats at PND60 compared to age-matched Long-Evan's rats, which revealed Shh/ptc pathway involving in the activation of RSCs. These results suggest that RSCs in the mammalian retinal proliferating marginal regions has the potential to regenerate following degeneration.     

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.