• 【功能性精子发生的发展需要早期大量的生发细胞凋亡。】 复制标题 收藏 收藏
    DOI:10.1093/emboj/16.9.2262 复制DOI
    作者列表:Rodriguez I,Ody C,Araki K,Garcia I,Vassalli P
    BACKGROUND & AIMS: Transgenic mice expressing high levels of the BclxL or Bcl2 proteins in the male germinal cells show a highly abnormal adult spermatogenesis accompanied by sterility. This appears to result from the prevention of an early and massive wave of apoptosis in the testis, which occurs among germinal cells during the first round of spermatogenesis. In contrast, sporadic apoptosis among spermatogonia, which occurs in normal adult testis, is not prevented in adult transgenic mice. The physiological early apoptotic wave in the testis is coincident, in timing and localization, with a temporary high expression of the apoptosis-promoting protein Bax, which disappears at sexual maturity. The critical role played by the intracellular balance, probably hormonally controlled, of the BclxL and Bax proteins (Bcl2 is apparently not expressed in normal mouse testis) in this early apoptotic wave is shown by the occurrence of a comparable testicular syndrome in mice defective in the bax gene. The apoptotic wave appears necessary for normal mature spermatogenesis to develop, probably because it maintains a critical cell number ratio between some germinal cell stages and Sertoli cells, whose normal functions and differentiation involve an elaborate network of communication.

    背景与目标: 在雄性生发细胞中表达高水平BclxL或Bcl2蛋白的转基因小鼠显示出高度异常的成年精子发生并伴有不育。这似乎是由于防止了睾丸中早期大量的凋亡波,而这种凋亡波在第一轮精子发生期间发生在生发细胞中。相反,在成年转基因小鼠中,不能阻止正常成年睾丸中发生的精原细胞间的零星凋亡。睾丸中的生理性早期凋亡波在时间和定位上是重合的,与促凋亡蛋白Bax的暂时高表达,该蛋白在性成熟时消失。BclxL和Bax蛋白 (Bcl2显然在正常小鼠睾丸中未表达) 的细胞内平衡 (可能受激素控制) 在这种早期凋亡波中起关键作用,这表现为在小鼠中出现类似的睾丸综合征。bax基因。凋亡波似乎是正常成熟精子发生发展所必需的,可能是因为它在某些生发细胞阶段和支持细胞之间保持了临界的细胞数比,支持细胞的正常功能和分化涉及复杂的通讯网络。
  • 【NLRX1通过控制线粒体活性抑制组织损伤中的氧化应激和凋亡。】 复制标题 收藏 收藏
    DOI:10.1084/jem.20161031 复制DOI
    作者列表:Stokman G,Kors L,Bakker PJ,Rampanelli E,Claessen N,Teske GJD,Butter L,van Andel H,van den Bergh Weerman MA,Larsen PWB,Dessing MC,Zuurbier CJ,Girardin SE,Florquin S,Leemans JC
    BACKGROUND & AIMS: :Mitochondrial dysfunction is the most prominent source of oxidative stress in acute and chronic kidney disease. NLRX1 is a receptor of the innate immune system that is ubiquitously expressed and localized in mitochondria. We investigated whether NLRX1 may act at the interface of metabolism and innate immunity in a model of oxidative stress. Using a chimeric mouse model for renal ischemia-reperfusion injury, we found that NLRX1 protects against mortality, mitochondrial damage, and epithelial cell apoptosis in an oxidative stress-dependent fashion. We found that NLRX1 regulates oxidative phosphorylation and cell integrity, whereas loss of NLRX1 results in increased oxygen consumption, oxidative stress, and subsequently apoptosis in epithelial cells during ischemia-reperfusion injury. In line, we found that NLRX1 expression in human kidneys decreased during acute renal ischemic injury and acute cellular rejection. Although first implicated in immune regulation, we propose that NLRX1 function extends to the control of mitochondrial activity and prevention of oxidative stress and apoptosis in tissue injury.
    背景与目标: : 线粒体功能障碍是急性和慢性肾脏疾病中氧化应激的最突出来源。NLRX1是先天免疫系统的受体,广泛表达并定位在线粒体中。我们研究了NLRX1是否可能在氧化应激模型中作用于代谢和先天免疫的界面。使用嵌合小鼠肾缺血再灌注损伤模型,我们发现NLRX1以氧化应激依赖性方式保护死亡率,线粒体损伤和上皮细胞凋亡。我们发现NLRX1调节氧化磷酸化和细胞完整性,而NLRX1的丢失会导致缺血再灌注损伤期间的耗氧量增加,氧化应激以及上皮细胞的凋亡。我们发现,在急性肾缺血损伤和急性细胞排斥反应期间,人肾脏中NLRX1的表达降低。尽管首先涉及免疫调节,但我们建议NLRX1功能扩展到控制线粒体活性以及预防组织损伤中的氧化应激和凋亡。
  • 【糖酵解代谢赋予HL60rho0细胞对全反式维甲酸和三氧化二砷联合诱导的凋亡的抵抗力。】 复制标题 收藏 收藏
    DOI:10.1016/j.leukres.2007.04.014 复制DOI
    作者列表:Herst PM,Hesketh EL,Ritchie DS,Berridge MV
    BACKGROUND & AIMS: :Glycolytic cancers are resistant to many forms of chemotherapy and some respond poorly to differentiation therapies. Here, we investigate the effects of exposure to all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) on differentiation and cell survival in the human leukemia cell line, HL60 and its mitochondrial gene knockout mutant, HL60rho0. Glycolytic HL60rho0 cells exposed to single and combined treatments expressed less CD15, in most cases, but produced a stronger respiratory burst than parental HL60 cells. HL60rho0 cells were also significantly more resistant to apoptosis after combined ATO+ATRA treatment compared with HL60 cells, and this was associated with failure to upregulate Fas expression.
    背景与目标: : 糖酵解性癌症对多种形式的化学疗法具有抵抗力,有些对分化疗法的反应较差。在这里,我们研究了暴露于全反式维甲酸 (ATRA) 和三氧化二砷 (ATO) 对人白血病细胞系HL60及其线粒体基因敲除突变体HL60rho0的分化和细胞存活的影响。在大多数情况下,暴露于单一和联合治疗的糖酵解HL60rho0细胞表达较少的CD15,但比亲代HL60细胞产生更强的呼吸爆发。与HL60细胞相比,联合ATO ATRA处理后,HL60rho0细胞对凋亡的抵抗力也明显增强,这与Fas表达上调失败有关。
  • 【p53抑癌基因和Fas/Apo-1在诱导癌细胞凋亡和分化中的作用。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Takahashi R
    BACKGROUND & AIMS: :Recent studies have suggested that wild-type p53 blocks cell cycle progression near the G1-S boundary and is involved in both differentiation and apoptosis in many types of cells including cancer cells. p53 expression is enhanced upon DNA-damaging apoptotic stimuli while Fas/Apo-1, a member of the tumor necrosis factor receptor family expressed on cell surface, transduces a signal for apoptosis upon specific ligand or antibody engagement. We demonstrated that stable transfection of the wild-type p53 gene under the control of CMV promoter induced differentiation and apoptosis under restricted conditions in cancer cells, and often caused sensitization of p53-transfected cells to Fas/Apo-1 signal. To investigate the interaction between two major apoptotic pathways involving p53 and Fas/Apo-1 we have established a system that allows to induce wild-type p53 overexpression and apoptosis in cancer cells upon treatment with anti-Fas antibody. The system also allows to investigate other factors interacting with p53 and Fas/Apo-1, and should provide a clue to understanding the biological and biochemical aspects of apoptosis.
    背景与目标: : 最近的研究表明,野生型p53阻断G1-S边界附近的细胞周期进程,并参与包括癌细胞在内的许多类型细胞的分化和凋亡。p53表达在破坏DNA的凋亡刺激时增强,而Fas/Apo-1 (在细胞表面表达的肿瘤坏死因子受体家族的成员) 在特异性配体或抗体接合时转导凋亡信号。我们证明,在CMV启动子控制下,野生型p53基因的稳定转染可在限制条件下诱导癌细胞的分化和凋亡,并经常引起p53-transfected细胞对Fas/Apo-1信号的敏感性。为了研究涉及p53和Fas/Apo-1的两个主要凋亡途径之间的相互作用,我们建立了一个系统,该系统允许在用抗Fas抗体治疗后诱导野生型p53过表达和癌细胞凋亡。该系统还允许研究与p53和Fas/Apo-1相互作用的其他因素,并且应该为了解凋亡的生物学和生化方面提供线索。
  • 【细胞凋亡信号通路与淋巴细胞稳态。】 复制标题 收藏 收藏
    DOI:10.1038/cr.2007.52 复制DOI
    作者列表:Xu G,Shi Y
    BACKGROUND & AIMS: :It has been almost three decades since the term "apoptosis" was first coined to describe a unique form of cell death that involves orderly, gene-dependent cell disintegration. It is now well accepted that apoptosis is an essential life process for metazoan animals and is critical for the formation and function of tissues and organs. In the adult mammalian body, apoptosis is especially important for proper functioning of the immune system. In recent years, along with the rapid advancement of molecular and cellular biology, great progress has been made in understanding the mechanisms leading to apoptosis. It is generally accepted that there are two major pathways of apoptotic cell death induction: extrinsic signaling through death receptors that leads to the formation of the death-inducing signaling complex (DISC), and intrinsic signaling mainly through mitochondria which leads to the formation of the apoptosome. Formation of the DISC or apoptosome, respectively, activates initiator and common effector caspases that execute the apoptosis process. In the immune system, both pathways operate; however, it is not known whether they are sufficient to maintain lymphocyte homeostasis. Recently, new apoptotic mechanisms including caspase-independent pathways and granzyme-initiated pathways have been shown to exist in lymphocytes. This review will summarize our understanding of the mechanisms that control the homeostasis of various lymphocyte populations.
    背景与目标: : 自从 “细胞凋亡” 一词首次被创造用来描述一种独特的细胞死亡形式以来,已经过去了近三十年,这种死亡形式涉及有序的基因依赖性细胞崩解。现在,人们普遍认为细胞凋亡是后生动物的基本生命过程,对于组织和器官的形成和功能至关重要。在成年哺乳动物体内,细胞凋亡对于免疫系统的正常运作尤其重要。近年来,随着分子生物学和细胞生物学的快速发展,人们对细胞凋亡机制的认识取得了很大进展。人们普遍认为,凋亡细胞死亡诱导有两种主要途径: 通过死亡受体的外在信号传导导致死亡诱导信号复合物 (DISC) 的形成,以及主要通过线粒体的内在信号传导导致细胞凋亡的形成。椎间盘或凋亡小体的形成分别激活执行凋亡过程的引发剂和常见的效应半胱天蛋白酶。在免疫系统中,两种途径都起作用; 但是,尚不清楚它们是否足以维持淋巴细胞的稳态。最近,淋巴细胞中存在新的凋亡机制,包括caspase非依赖性途径和颗粒酶启动途径。这篇综述将总结我们对控制各种淋巴细胞群体稳态机制的理解。
  • 【精子凋亡信号与卵母细胞穿透能力的关系。】 复制标题 收藏 收藏
    DOI:10.1111/j.1365-2605.2007.00768.x 复制DOI
    作者列表:Grunewald S,Said TM,Paasch U,Glander HJ,Agarwal A
    BACKGROUND & AIMS: :Human sperm have been documented to display apoptosis-like features such as externalization of phosphatidylserine (EPS), disruption of the transmembrane mitochondrial potential (MMP) and activation of caspases. Our aim was to evaluate possible association between activation of the apoptosis cascade in human sperm and its oocyte penetration capacity using the zona free hamster oocyte penetration assay (SPA). Semen specimens from 76 unselected donors were subjected to double density gradient centrifugation followed by incubation under capacitating conditions for 3 h and SPA. Apoptosis signalling was monitored by assessment of EPS, disruption of MMP and activation of caspase-3 by flow cytometry. Semen samples with subnormal SPA values (<20% penetrated oocytes) contained significantly higher amounts of spermatozoa with EPS, disrupted MMP and activated caspase-3 compared with those samples with normal SPA values (>20% penetrated oocytes, p < 0.01). All three apoptosis markers showed a significantly negative correlation with the percentage of penetrated oocytes (p < 0.01). Apoptosis-related signalling appears to have a negative association with sperm-oocyte penetration. The exclusion of sperm presenting with those apoptosis-related features during assisted reproduction may improve success rates of procedures such as intrauterine insemination and in vitro fertilization.
    背景与目标: : 人类精子已被证明具有凋亡样特征,例如磷脂酰丝氨酸 (EPS) 的外部化,跨膜线粒体电位 (MMP) 的破坏和胱天蛋白酶的激活。我们的目的是使用无带仓鼠卵母细胞渗透试验 (SPA) 评估人类精子中凋亡级联的激活与其卵母细胞渗透能力之间的可能关联。对来自76个未选择的供体的精液标本进行双密度梯度离心,然后在容量条件下孵育3小时和SPA。通过流式细胞术评估EPS,MMP破坏和caspase-3激活来监测凋亡信号。与具有正常SPA值 (>20% 穿透卵母细胞,p <0.01) 的那些样品相比,具有低于正常SPA值 (<20% 穿透卵母细胞) 的精液样品含有显著更高量的具有EPS、破坏的MMP和活化caspase-3的精子。3种凋亡标记物均与穿透卵母细胞的百分比呈显著负相关 (p <0.01)。凋亡相关信号似乎与精子卵母细胞的渗透呈负相关。在辅助生殖过程中排除具有凋亡相关特征的精子可能会提高子宫内人工授精和体外受精等手术的成功率。
  • 【牛乳铁蛋白通过连续渗透细胞膜和靶向线粒体而导致Jurkat T-白血病细胞凋亡。】 复制标题 收藏 收藏
    DOI:10.1016/j.yexcr.2007.05.015 复制DOI
    作者列表:Mader JS,Richardson A,Salsman J,Top D,de Antueno R,Duncan R,Hoskin DW
    BACKGROUND & AIMS: :Bovine lactoferricin (LfcinB) is a cationic antimicrobial peptide that kills Jurkat T-leukemia cells by the mitochondrial pathway of apoptosis. However, the process by which LfcinB triggers mitochondria-dependent apoptosis is not well understood. Here, we show that LfcinB-induced apoptosis in Jurkat T-leukemia cells was preceded by LfcinB binding to, and progressive permeabilization of the cell membrane. Colloidal gold electron microscopy revealed that LfcinB entered the cytoplasm of Jurkat T-leukemia cells prior to the onset of mitochondrial depolarization. LfcinB was not internalized by endocytosis because endocytosis inhibitors did not prevent LfcinB-induced cytotoxicity. Furthermore, intracellular delivery of LfcinB via fusogenic liposomes caused the death of Jurkat T-leukemia cells, as well as normal human fibroblasts. Collectively, these findings suggest that LfcinB caused damage to the cell membrane that allowed LfcinB to enter the cytoplasm of Jurkat T-leukemia cells and mediate cytotoxicity. In addition, confocal microscopy showed that intracellular LfcinB co-localized with mitochondria in Jurkat T-leukemia cells, while flow cytometry and colloidal gold electron microscopy showed that LfcinB rapidly associated with purified mitochondria. Furthermore, purified mitochondria treated with LfcinB rapidly lost transmembrane potential and released cytochrome c. We conclude that LfcinB-induced apoptosis in Jurkat T-leukemia cells resulted from cell membrane damage and the subsequent disruption of mitochondrial membranes by internalized LfcinB.
    背景与目标: 牛乳铁蛋白 (LfcinB) 是一种阳离子抗菌肽,可通过线粒体凋亡途径杀死Jurkat T-白血病细胞。然而,LfcinB触发线粒体依赖性细胞凋亡的过程尚不清楚。在这里,我们显示LfcinB诱导的Jurkat T白血病细胞凋亡之前,LfcinB与细胞膜结合并逐渐通透。胶体金电子显微镜显示,在线粒体去极化开始之前,LfcinB进入了Jurkat T-白血病细胞的细胞质。由于内吞作用抑制剂不能阻止LfcinB诱导的细胞毒性,因此LfcinB不会被内吞作用内化。此外,通过融合脂质体在细胞内递送LfcinB会导致Jurkat T-白血病细胞以及正常人成纤维细胞死亡。总的来说,这些发现表明LfcinB对细胞膜造成了损害,使LfcinB进入Jurkat T-白血病细胞的细胞质并介导了细胞毒性。此外,共聚焦显微镜显示细胞内LfcinB与线粒体共定位于Jurkat T-白血病细胞,而流式细胞术和胶体金电子显微镜显示LfcinB与纯化的线粒体迅速相关。此外,用LfcinB处理的纯化线粒体迅速失去跨膜电位并释放细胞色素c。我们得出结论,LfcinB诱导的Jurkat T-白血病细胞凋亡是由细胞膜损伤和随后内在化的LfcinB破坏线粒体膜引起的。
  • 【作为载气混合物的一部分,氢气的共同给药可抑制小鼠新生儿暴露于七氟醚引起的神经元凋亡和随后的行为缺陷。】 复制标题 收藏 收藏
    DOI:10.1097/ALN.0b013e318275146d 复制DOI
    作者列表:Yonamine R,Satoh Y,Kodama M,Araki Y,Kazama T
    BACKGROUND & AIMS: BACKGROUND:In animal models, several anesthetics induce widespread increases in neuronal apoptosis in the developing brain with subsequent neurologic deficits. Although the mechanisms are largely unknown, the neurotoxicity may, at least in part, be due to elevated oxidative stress caused by mitochondrial dysfunction. In an investigation of potential therapies that could protect against this type of damage, we studied the effects of molecular hydrogen on anesthetic-induced neurotoxicity in the developing mouse brain. METHODS:Six-day-old C57BL/6 mice were exposed to 3% sevoflurane for 6 h with or without hydrogen (< 1.3%) as part of the carrier gas mixture. Apoptosis was evaluated by immunohistochemical staining for cleaved caspase-3 (n = 8-10/group). Western blot analysis for cleaved poly-(adenosine diphosphate-ribose) polymerase was also performed to examine apoptosis (n = 3-6/group). Oxidative stress was assessed by immunohistochemical staining for 4-hydroxy-2-nonenal (n = 8/group). Long-term memory and social behavior were examined using the fear conditioning test and the sociability test, respectively (n = 18-20/group). RESULTS:Western blot analysis showed that coadministration of 1.3% hydrogen gas significantly (P < 0.001) reduced the level of neuronal apoptosis to approximately 40% compared with sevoflurane exposure alone. Immunohistochemical analysis showed that hydrogen reduced oxidative stress induced by neonatal sevoflurane exposure. Although neonatal sevoflurane exposure caused impairment in long-term memory and abnormal social behaviors in adulthood, mice coadministered hydrogen gas with sevoflurane did not exhibit these deficits. CONCLUSIONS:Inhalation of hydrogen gas robustly decreased neuronal apoptosis and subsequent cognitive impairments caused by neonatal exposure to sevoflurane.
    背景与目标:
  • 【迷迭香酸通过抑制肝星状细胞活化/增殖和诱导凋亡来减弱肝纤维化。】 复制标题 收藏 收藏
    DOI:10.1016/j.apjtm.2017.05.012 复制DOI
    作者列表:El-Lakkany NM,El-Maadawy WH,Seif El-Din SH,Hammam OA,Mohamed SH,Ezzat SM,Safar MM,Saleh S
    BACKGROUND & AIMS: OBJECTIVE:To investigate the antifibrotic role of rosmarinic acid (RA), a natural polyphenolic compound, on HSCs activation/proliferation and apoptosis in vitro and in vivo. METHODS:The impact of RA on stellate cell line (HSC-T6) proliferation, activation and apoptosis was assessed along with its safety on primary hepatocytes. In vivo, rats were divided into: (i) normal; (ii) thioacetamide (TAA)-intoxicated rats for 12 weeks; (iii) TAA + silymarin or (iv) TAA + RA. At the end of experiment, liver functions, oxidative stress, inflammatory and profibrogenic markers, tissue inhibitor metalloproteinases type-1 (TIMP-1) and hydroxyproline (HP) levels were evaluated. Additionally, liver histopathology and immunohistochemical examinations of alpha-smooth muscle actin (α-SMA), caspase-3 and proliferation cellular nuclear antigen (PCNA) were determined. RESULTS:RA exhibited anti-proliferative effects on cultured HSCs in a time and concentration dependent manner showing an IC50 of 276 μg/mL and 171 μg/mL for 24 h and 48 h, respectively, with morphological reversion of activated stellate cell morphology to quiescent form. It significantly improved ALT, AST, oxidative stress markers and reduced TIMP-1, HP levels, inflammatory markers and fibrosis score (S1 vs S4). Furthermore, reduction in α-SMA plus elevation in caspase-3 expressions of HSCs in vitro and in vivo associated with an inhibition in proliferation of damaged hepatocytes were recorded. CONCLUSIONS:RA impeded the progression of liver fibrosis through inhibition of HSCs activation/proliferation and induction of apoptosis with preservation of hepatic architecture.
    背景与目标:
  • 【细胞外PAR-4介导的肿瘤细胞凋亡抵抗的新机制。】 复制标题 收藏 收藏
    DOI:10.1158/0008-5472.CAN-12-3212 复制DOI
    作者列表:Burikhanov R,Shrestha-Bhattarai T,Qiu S,Shukla N,Hebbar N,Lele SM,Horbinski C,Rangnekar VM
    BACKGROUND & AIMS: :Tumor suppressor PAR-4 acts in part by modulating sensitivity to apoptosis, but the basis for its activity is not fully understood. In this study, we describe a novel mechanism of antiapoptosis by NF-κB, revealing that it can block PAR-4-mediated apoptosis by downregulating trafficking of the PAR-4 receptor GRP78 from the endoplasmic reticulum to the cell surface. Mechanistic investigations revealed that NF-κB mediated this antiapoptotic mechanism by upregulating expression of UACA, a proinflammatory protein in certain disease settings. In clinical specimens of cancer, a strong correlation existed between NF-κB activity and UACA expression, relative to normal tissues. UACA bound to intracellular PAR-4 in diverse cancer cells, where it prevented translocation of GRP78 from the endoplasmic reticulum to the cell surface. This pathway of antiapoptosis could be inhibited by suppressing levels of NF-κB or UACA expression, which enhanced endoplasmic reticulum stress and restored GRP78 trafficking to the cell surface, thereby sensitizing cancer cells to apoptosis by extracellular PAR-4 or GRP78 agonistic antibody. In summary, our results identify a novel intracellular pathway of apoptosis mediated by NF-κB through UACA elevation, which by attenuating endoplasmic reticulum stress and GRP78 translocation to the cell surface can blunt the sensitivity of cancer cells to apoptosis.
    背景与目标: : 肿瘤抑制因子PAR-4部分通过调节对凋亡的敏感性起作用,但其活性的基础尚不完全清楚。在这项研究中,我们描述了NF-κ b抗凋亡的新机制,揭示了它可以通过下调PAR-4受体GRP78从内质网到细胞表面的运输来阻断PAR-4介导的凋亡。机理研究表明,NF-κ b通过上调UACA (在某些疾病环境中是一种促炎蛋白) 的表达来介导这种抗凋亡机制。在癌症的临床标本中,相对于正常组织,NF-κ b活性与UACA表达之间存在很强的相关性。UACA与多种癌细胞中的细胞内PAR-4结合,阻止了GRP78从内质网转移到细胞表面。抑制NF-κ b或UACA表达的水平可以抑制这种抗凋亡途径,从而增强内质网应激并恢复GRP78向细胞表面的运输,从而使癌细胞对细胞外PAR-4或GRP78激动抗体的凋亡敏感。总之,我们的结果确定了由NF-κ b通过UACA升高介导的新的细胞内凋亡途径,该途径通过减弱内质网应激和GRP78易位到细胞表面可以减弱癌细胞对凋亡的敏感性。
  • 【泼尼松龙通过内在途径诱导角膜上皮细胞凋亡。】 复制标题 收藏 收藏
    DOI:10.1038/s41598-017-04509-8 复制DOI
    作者列表:Ryu JS,Ko JH,Kim MK,Wee WR,Oh JY
    BACKGROUND & AIMS: :Glucocorticoid eye drops are one of the most widely used medications in ophthalmology. However, little is known about the effects of glucocorticoids on corneal epithelial cells that are directly exposed to topically-administered glucocorticoids. Here we investigated the effects of prednisolone, a synthetic glucocorticoid analogue frequently used in the clinic, on corneal epithelial cells. Results showed that prednisolone decreased survival of corneal epithelial cells by inhibiting proliferation and inducing apoptosis in a dose-dependent manner. The levels of mitochondrial reactive oxygen species (mtROS), cleaved caspase-3, and -9 were increased by prednisolone. The effects of prednisolone on apoptosis and mtROS were blocked 1) by the glucocorticoid receptor (GR) antagonist RU-38486, 2) in cells with GR siRNA knockdown, and 3) by treatment with N-acetylcysteine. Transcript levels of pro-inflammatory cytokines were increased in corneal epithelial cells upon hyperosmolar stress, but repressed by prednisolone. In NOD.B10.H2b mice, topical administration of 1% prednisolone increased apoptotic cells in the corneal epithelium. Together, data indicate that prednisolone induces apoptosis in corneal epithelial cells through GR and the intrinsic pathway involving mtROS, caspase-9, and -3. The pro-apoptotic effects of glucocorticoids along with their anti-inflammatory effects should be considered when glucocorticoid eye drops are used in patients with ocular surface disease.
    背景与目标: : 糖皮质激素滴眼液是眼科使用最广泛的药物之一。然而,关于糖皮质激素对直接暴露于局部施用糖皮质激素的角膜上皮细胞的影响知之甚少。在这里,我们研究了泼尼松龙 (一种临床上经常使用的合成糖皮质激素类似物) 对角膜上皮细胞的影响。结果表明,泼尼松龙通过抑制增殖和诱导凋亡以剂量依赖性方式降低了角膜上皮细胞的存活率。泼尼松龙增加了线粒体活性氧 (mtROS),裂解caspase-3和-9的水平。泼尼松龙对细胞凋亡和mtROS的影响被1) 糖皮质激素受体 (GR) 拮抗剂RU-38486阻断,2) 用GR siRNA敲低的细胞中,以及3) 用N-乙酰半胱氨酸处理。高渗应激时,角膜上皮细胞中促炎细胞因子的转录水平增加,但被泼尼松龙抑制。在NOD.B10.H2b小鼠中,局部施用1% 泼尼松龙增加了角膜上皮中的凋亡细胞。总之,数据表明泼尼松龙通过GR和涉及mtROS,caspase-9和-3的内在途径诱导角膜上皮细胞凋亡。当糖皮质激素滴眼液用于眼表疾病患者时,应考虑糖皮质激素的促凋亡作用及其抗炎作用。
  • 【新型三环化合物作为凋亡蛋白 (IAP) 拮抗剂抑制剂的设计,立体选择性合成和生物学评估。】 复制标题 收藏 收藏
    DOI:10.1016/j.bmc.2013.07.020 复制DOI
    作者列表:Asano M,Hashimoto K,Saito B,Shiokawa Z,Sumi H,Yabuki M,Yoshimatsu M,Aoyama K,Hamada T,Morishita N,Dougan DR,Mol CD,Yoshida S,Ishikawa T
    BACKGROUND & AIMS: :We recently reported the discovery of octahydropyrrolo[1,2-a]pyrazine A as a lead compound for an inhibitor of apoptosis proteins (IAP) antagonist. To develop IAP antagonists with favorable PK profiles, we designed novel tri-cyclic compounds, octahydro-1H-cyclopropa[4,5]pyrrolo[1,2-a]pyrazines 1 and 2 based on co-crystal structural analysis of A with cellular IAP-1 (cIAP-1). The additional cyclopropane moiety was used to block the predicted metabolic site of compound A without detriment to the binding affinity for cIAP. Compounds 1 and 2 were stereoselectively synthesized via intermediates 4a and 5b', which were obtained by Simmons-Smith cyclopropanation of ethylester 3a and silyl ether 3b'. Compounds 1 and 2 showed strong growth inhibition in MDA-MB-231 breast cancer cells and improved metabolic stability in comparison to A. Compound 2 exhibited significant in vivo PD effects to increase tumor necrosis factor-alpha mRNA in a dose dependent manner.
    背景与目标: : 我们最近报道了八氢吡咯并 [1,2-a] 吡嗪A作为凋亡蛋白抑制剂 (IAP) 拮抗剂的领先化合物的发现。为了开发具有良好PK谱的IAP拮抗剂,我们设计了新的三环化合物,octahydro-1H-cyclopropa[4,5] 吡咯并 [1,2-a] 吡嗪1和2基于A与细胞IAP-1 (cIAP-1) 的共晶体结构分析。额外的环丙烷部分用于阻断化合物A的预测代谢位点,而不损害对cIAP的结合亲和力。化合物1和2通过中间体4a和5b' 立体选择性合成,它们是通过乙酸酯3a和甲硅烷基醚3b' 的Simmons-Smith环丙烷化获得的。与A相比,化合物1和2在MDA-MB-231乳腺癌细胞中显示出强烈的生长抑制作用,并改善了代谢稳定性。化合物2表现出显著的体内PD效应,以剂量依赖性方式增加肿瘤坏死因子-α mRNA。
  • 【通过彗星形成评估Tea诱导的人白血病K562细胞凋亡。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Chakraborty S,Kundu T,Dey S,Bhattacharya RK,Siddiqi M,Roy M
    BACKGROUND & AIMS: :Programmed cell death or apoptosis is a physiological process by which genetically damaged cells or undesired cells can be eliminated. Various morphological and molecular changes undergoing during the process of apoptosis are the formation of apoptotic blebs of the cell membrane, cell shrinkage, condensation of chromatin and the disruption of deoxyribonucleic acid (DNA) into typical fragments of multiples of 180 base pairs. These changes can be detected in a number of ways. DNA ladder formation, which is observed following gel electrophoresis technique although is widely accepted but does not reflect the DNA breakdown in individual cell and also may miss contributions from small sub-populations in a heterogeneous cell population. Alkaline comet assay as measured by single cell gel electrophoresis, on the other hand, accurately measures DNA fragmentation on a single cell level and allows analysis of subpopulation of cells. The assay was originally developed for measuring DNA damage of cells exposed to any genotoxic agent. However, the comet image generated by an apoptotic cell is different from that obtained with a cell treated for a short time with a genotoxic agent. Correlation of comet formation with various other established parameters of apoptosis is very important. The present study aims to correlate different features of apoptosis with the formation of comet tail in human leukemia K-562 cells using tea extracts. Apoptosis as measured by formation of apoptotic bodies, flow cytometric analysis, activation of caspase 3 and 8, and expressions of apoptosis related genes such as bcl-2 and bax showed high degree of correlation with comet tail moment. This indicates that comet assay can accurately reflect measure of DNA fragmentation and hence can be used to detect a cell undergoing apoptosis.
    背景与目标: : 程序性细胞死亡或凋亡是一种生理过程,通过该过程可以消除遗传受损的细胞或不希望的细胞。在细胞凋亡过程中发生的各种形态和分子变化是细胞膜凋亡泡的形成,细胞收缩,染色质的浓缩以及脱氧核糖核酸 (DNA) 破坏成多个180碱基对的典型片段。可以通过多种方式检测这些变化。通过凝胶电泳技术观察到的DNA阶梯形成,尽管已被广泛接受,但并未反映单个细胞中的DNA分解,并且可能会错过异质细胞群中小亚群的贡献。另一方面,通过单细胞凝胶电泳测量的碱性彗星分析可以在单细胞水平上准确地测量DNA片段化,并可以分析细胞亚群。该测定法最初是为测量暴露于任何遗传毒性剂的细胞的DNA损伤而开发的。然而,由凋亡细胞产生的彗星图像与用遗传毒性剂处理短时间的细胞获得的图像不同。彗星形成与其他各种已建立的凋亡参数的相关性非常重要。本研究旨在使用tea提取物将细胞凋亡的不同特征与人类白血病K-562细胞中彗尾的形成相关联。通过凋亡小体的形成,流式细胞术分析,caspase 3和8的激活以及凋亡相关基因 (例如bcl-2和bax) 的表达来测量凋亡,与彗星尾矩高度相关。这表明彗星分析可以准确反映DNA片段的测量,因此可以用于检测细胞凋亡。
  • 【氧化应激对锰诱导的公鸡睾丸毒性细胞凋亡的影响。】 复制标题 收藏 收藏
    DOI:10.1016/j.fct.2013.07.058 复制DOI
    作者列表:Liu XF,Zhang LM,Guan HN,Zhang ZW,Xu SW
    BACKGROUND & AIMS: :Manganese (Mn) is a trace element known to be essential for maintaining the proper function and regulation of many biochemical and cellular reactions. However, little is known about the reproductive toxicity of Mn in birds. To investigate the toxicity of Mn on male reproduction in birds, 50-day-old cocks were fed either a commercial diet or a Mn-supplemented diet containing 600, 900, and 1800 mg/kg MnCl₂. After being treated with Mn for 30, 60, and 90 d, the following were determined: Mn content; histological and ultrastructural changes in the testes, apoptosis; the malondialdehyde (MDA) level; the activities of superoxide dismutase (SOD); the inhibition ability of hydroxyl radicals (OH); the levels of nitric oxide (NO), nitric oxide synthase (NOS), and protein carbonyl in the testes; the DNA-protein crosslinks (DPC); and the activity of the ATP enzyme. Exposure to Mn significantly lowered the activity of SOD and glutathione peroxidase (GPx) and the inhibition ability of OH. Mn exposure also increased the levels of MDA, NO, NOS, DPC, and protein carbonyl; the number of apoptotic cells; and the Mn content and caused obvious histopathological changes in the testes. These findings suggested that Mn exposure resulted in the oxidative damage of cock testicular tissue by altering radical formation, ATP enzyme systems, apoptosis, and DNA damage, which are possible underlying reproductive toxicity mechanisms induced by Mn exposure.
    背景与目标: : 锰 (Mn) 是一种微量元素,已知对维持许多生化和细胞反应的正常功能和调节至关重要。然而,对Mn在鸟类中的生殖毒性知之甚少。为了研究Mn对鸟类雄性繁殖的毒性,对50天大的公鸡进行了商业饮食或含有600,900和1800 mg/kg mncl 2的补充Mn的饮食。用Mn处理30、60和90 d后,测定以下含量: Mn含量; 睾丸的组织学和超微结构变化,细胞凋亡; 丙二醛 (MDA) 水平; 超氧化物歧化酶 (SOD) 的活性; 羟基自由基 (OH) 的抑制能力; 睾丸中一氧化氮 (NO),一氧化氮合酶 (NOS) 和蛋白羰基的水平; DNA-蛋白质交联 (DPC); 和ATP酶的活性。暴露于Mn会显着降低SOD和谷胱甘肽过氧化物酶 (GPx) 的活性以及OH的抑制能力。Mn暴露还增加了MDA,NO,NOS,DPC和羰基蛋白的水平; 凋亡细胞的数量; 和Mn含量,并在睾丸中引起明显的组织病理学变化。这些发现表明,Mn暴露通过改变自由基形成,ATP酶系统,凋亡和DNA损伤而导致公鸡睾丸组织的氧化损伤,这可能是Mn暴露引起的潜在生殖毒性机制。
  • 【Bcl-2家族成员在铜绿假单胞菌感染U937细胞caspase-3/9依赖性凋亡中的作用。】 复制标题 收藏 收藏
    DOI:10.1007/s10495-008-0197-6 复制DOI
    作者列表:Chai WS,Zhu XM,Li SH,Fan JX,Chen BY
    BACKGROUND & AIMS: :Pseudomonas aeruginosa is a gram-negative opportunistic pathogen that is cytotoxic towards a variety of eukaryotic cells. To investigate the effect of this bacterium on monocyte, we infected human U937 cells with the P. aeruginosa strain in vitro. To explore the expression of Bcl-2 and Bax as well as caspase-3/9 activation in the apoptosis of human U937 cells induced by P. aeruginosa, Hoechst 33258 staining and Giemsa staining as well as Flow cytometry analysis were used to determine the rate of apoptosis, and the expressions of Bcl-2 and Bax were assayed by RT-PCR and Western blotting respectively. Bax protein conformation change was assayed by immunoprecipitation. Cytochrome c release was measured by Western blotting. Moreover, exposure of U937 cells to P. aeruginosa measured caspase-3/9 activity. It was found that the apoptosis of human U937 cells could be induced by Pseudomonas aeruginosa in a dose- and time-dependent manner. Also, there were a tendency of alterations with an increased expression level of Bax and a reduced expression level of Bcl-2, increased levels of cytochrome c release, and also with an increased activation of caspase-3/9 and Bax protein conformation change. For the evaluation of the role of caspases, caspase-3/9 inhibitors Z-DEVD-FMK and Z-LEHD-FMK respectively were used. The results were further confirmed by the observation that the caspase inhibitors Z-DEVD-FMK and Z-LEHD-FMK blocked P. aeruginosa-induced U937 apoptosis. It is concluded that P. aeruginosa can induce apoptosis with an up-regulated expression of Bax and a down-regulated expression of Bcl-2, which resulted in increased levels of cytochrome c release and increased caspase-3 and -9 in human U937 cells.
    背景与目标: 铜绿假单胞菌是一种革兰氏阴性机会性病原体,对多种真核细胞具有细胞毒性。为了研究这种细菌对单核细胞的影响,我们在体外用铜绿假单胞菌菌株感染了人U937细胞。为探讨铜绿假单胞菌诱导人U937细胞凋亡中Bcl-2和Bax的表达以及caspase-3/9的激活,采用Hoechst 33258染色和Giemsa染色以及流式细胞仪分析测定凋亡率。用rt-pcr和Western blotting分别检测Bcl-2和Bax的表达。通过免疫沉淀测定Bax蛋白构象变化。通过蛋白质印迹法测量细胞色素c的释放。此外,暴露于铜绿假单胞菌的U937细胞可测量caspase-3/9活性。发现铜绿假单胞菌可以剂量和时间依赖性地诱导人U937细胞的凋亡。此外,随着Bax表达水平的增加和Bcl-2表达水平的降低,细胞色素c释放水平的增加以及caspase-3/9和Bax蛋白构象变化的增加,存在改变的趋势。为了评估半胱天冬酶的作用,分别使用caspase-3/9抑制剂Z-DEVD-FMK和Z-LEHD-FMK。观察结果进一步证实,caspase抑制剂Z-DEVD-FMK和Z-LEHD-FMK阻断了铜绿假单胞菌诱导的U937凋亡。结论铜绿假单胞菌可诱导凋亡,Bax表达上调,Bcl-2表达下调,导致人U937细胞细胞色素c释放水平升高,caspase-3和-9增加。

+1
+2
100研值 100研值 ¥99课程
检索文献一次
下载文献一次

去下载>

成功解锁2个技能,为你点赞

《SCI写作十大必备语法》
解决你的SCI语法难题!

技能熟练度+1

视频课《玩转文献检索》
让你成为检索达人!

恭喜完成新手挑战

手机微信扫一扫,添加好友领取

免费领《Endnote文献管理工具+教程》

微信扫码, 免费领取

手机登录

获取验证码
登录