脑缺血中Bcl-2对自噬与凋亡的双重调控机制

脑缺血是一种高死亡率、高致残率的神经退行性疾病。脑缺血发病时,自噬与凋亡是缺血半暗带区神经元的主要死亡方式,减轻缺血半暗带区脑组织损伤和改善神经元症状是治疗脑缺血的重要措施。B淋巴细胞瘤-2基因(B-cell lymphoma-2,Bcl-2)不但是最经典的抗凋亡基因,而且与细胞的自噬通路密切相关。Bcl-2可以双重调控自噬与凋亡的信号通路,从而影响脑缺血后神经元的存活。该文分析了脑缺血与细胞自噬及凋亡的关系,并综述了Bcl-2介导的自噬与凋亡对脑缺血的作用及其双重调控机制,以期为中医药防治脑缺血研究提供新的靶点以及理论依据。     

苦参碱诱导人肝癌细胞BEL-7402自吞噬性死亡

目的研究苦参碱诱导人肝癌BEL-7402细胞自吞噬和自吞噬性死亡作用。方法体外培养人肝癌BEL-7402细胞,应用MTT法测定细胞增殖抑制率,流式细胞术测定细胞凋亡,自噬体标记物LC3免疫荧光定量检测自吞噬,透射电镜分析细胞自吞噬死亡超微结构改变。结果苦参碱抑制细胞增殖呈质量浓度依赖性,作用48h的IC50值为1.1mg/mL;0.6～1.6mg/mL苦参碱作用12h可诱导BEL-7402细胞凋亡逐渐增多,1.2mg/mL作用12h时细胞凋亡率达(44.88±0.78)%;1.2mg/mL苦参碱持续作用可以诱导自吞噬阳性细胞逐渐增多,作用12h时自吞噬阳性细胞达(63.16±0.29)%;超微结构显示细胞凋亡呈现自噬性细胞死亡特点。结论苦参碱体外能诱导BEL-7402细胞自吞噬和自噬性死亡。     

自噬-凋亡平衡调控在结直肠癌中的作用及中药干预研究进展

结直肠癌（CRC）是起源于结直肠黏膜上皮的消化系统恶性肿瘤,在进展到晚期之前通常是一种无症状的疾病。该病全球发病率居高不下,且呈年轻化趋势,严重威胁患者的健康与生命安全。该病病理机制尚未完全明确,与细胞自噬、凋亡和炎症反应等相关。自噬和凋亡同属于细胞程序性死亡,存在着复杂的交互调控,二者失衡与诸多疾病的发生、发展及预后密切相关。细胞自噬-凋亡失衡是CRC主要的病理基础,在CRC发病中起关键作用。一方面,自噬与凋亡互相协同,共同抑制CRC细胞生长;另一方面,自噬可以拮抗凋亡而促进CRC细胞生长。目前,临床治疗CRC的手段以手术联合放疗、化疗的综合治疗方案为主,可以在一定程度上控制CRC的进展,但不良反应较大、远期效果不佳。近年来,中医药在治疗CRC上取得了一定成效,发现众多中药单体可以通过调控自噬-凋亡平衡,促进CRC细胞死亡,从而阻断该病的进展。基于自噬-凋亡平衡调控细胞生命的进程,发现其蕴含着中医阴阳理论的变化规律,具有相似的理论内涵。中医药调控自噬-凋亡平衡参与CRC的各个阶段,已成为研究的前沿方向,但目前尚缺乏全面系统的阐述。基于此,该文总结了近年来的相关研究进行系统综述,主要介...     

补中益气汤含药血清诱导A549细胞自噬性死亡的研究

目的:研究补中益气汤含药血清诱导人肺腺癌A549细胞自噬性死亡并探讨其分子机制。方法:利用血清药理学方法制备含药血清,并干预A549细胞,分别应用光学显微镜观察细胞生长状况、MTT法检测细胞增殖情况、电子显微镜观察凋亡小体、蛋白质免疫印迹方法检测自噬相关蛋白的表达水平。结果:补中益气汤含药血清能抑制A549细胞增殖并诱导A549细胞发生自噬性死亡。结论:补中益气汤含药血清可诱导A549细胞发生自噬性死亡。     

人参皂苷Rh_2通过激活p38诱导K562细胞自噬凋亡的实验研究

为了研究人参皂苷Rh2对人白血病细胞K562的凋亡作用,并从自噬角度来探讨其机制。实验采用CCK-8方法检测人参皂苷单体Rh2对人白血病K562细胞增殖抑制作用;流式细胞术检测细胞凋亡;Hoechest染色观察细胞核染色质的形态;吖啶橙和MDC染色观察Rh2对细胞自噬的影响;Western blot和RT-PCR检测Rh2对白血病细胞自噬重要基因的表达的影响;运用自噬抑制剂(3-MA)研究自噬对细胞增殖和凋亡的影响。CCK-8显示人参皂苷Rh2在低浓度时能有效抑制白血病细胞增殖,且其抑制作用具有浓度和时间依赖性;FCM和Hoechest显示Rh2能增加细胞的凋亡和染色质呈凋亡形态改变;吖啶橙和MDC染色发现Rh2组细胞的绿色荧光增强,并出现大量酸性自噬小泡;Western blot和RT-PCR结果发现Rh2能上调Beclin-1,LC3A,LC3B,激活型Caspase-3和p-p38的表达;运用细胞自噬剂(3-MA)会削弱Rh2对K562的增殖抑制和促凋亡作用。人参皂苷Rh2可能通过激活磷酸化的p38,诱导细胞自噬途径,从而抑制K562细胞增殖和促进凋亡作用。     

略论自噬与凋亡相互关系的分子机制

在全部的细胞中随处可见自噬囊泡,尤其在营养缺失或者缺氧缺血等条件下会呈现出更多。诱导的自噬为细胞提供了能量且可降解受损的细胞。自噬以及凋亡都是程序性细胞死亡,如今尚知的是凋亡和自噬在疾病病理发展的进程中扮演着不可或缺的角色,其中包括自身免疫性疾病、神经退行性病变、癌症以及老化等。笔者针对凋亡和自噬关系的分子机制的研究步伐来做出综述。     

中医药靶向调节p53介导的铁死亡机制研究进展

铁死亡是一种新发现的非凋亡调节性细胞死亡形式，以铁依赖性的脂质过氧化物及活性氧（ROS）累积为主要特征。p53是一种抑癌基因，可以通过介导多种关键细胞基因的转录调控，诱导细胞周期阻滞、凋亡、自噬和衰老，进而维持基因组稳定性。新近研究发现p53还可通过影响铁代谢、多不饱和脂肪酸（PUFAs）代谢、氨基酸代谢和烟酰胺腺嘌呤二核苷酸磷酸盐（NADPH）介导的多种细胞代谢过程，调控铁死亡，参与肿瘤、神经系统疾病、心血管疾病、肝病、肾病等疾病的病理进展。该文对p53介导的铁死亡在相关疾病转归中的作用机制及其影响因素进行了系统综述，同时追踪了中医药靶向调节p53介导的铁死亡防治肿瘤、脑卒中、急性心肌梗死、慢性心力衰竭、动脉粥样硬化、溃疡性结肠炎、佐剂性关节炎等疾病的研究进展，以期为相关疾病的防治提供新思路。     

槲皮素诱导MCF-7细胞死亡机制中自噬与凋亡的相关性

 目的 研究槲皮素（quercetin,Que）在人乳腺癌细胞系（MCF-7）死亡中的作用,初步探讨自噬和凋亡机制在MCF-7死亡中的相关性。方法 采用噻唑蓝（MTT）法测定Que对MCF-7细胞的抑制作用; AO/EB染色、Hochest33258染色、单丹磺酰尸胺（MDC）、免疫荧光法观察给药后自噬和凋亡的发生;MTT法结合乳酸脱氢酶（LDH）漏出率和流式细胞仪研究自噬与凋亡机制在MCF-7死亡中的关系。结果 Que对MCF-7生长有显著抑制作用,呈明显的时间、剂量依赖性; Que可诱导MCF-7 细胞发生自噬和凋亡;在Que给药前用3-甲基腺嘌呤（3-MA）阻断自噬或用氯喹碱化溶酶体,Que对MCF-7的细胞毒性作用增强;碱化溶酶体后,Que可使 MCF-7细胞的凋亡峰提前;溶酶体组织蛋白酶抑制剂E64d能降低Que对MCF-7细胞的生长抑制。结论 Que能明显抑制MCF-7细胞的生长,并诱导其发生自噬和凋亡,自噬在早期起保护作用,另一方面溶酶体组织蛋白酶可能参与了Que诱导的MCF-7细胞死亡;溶酶体可能是MCF-7细胞发生自噬和凋亡的枢纽。     

厚朴酚通过自噬途径促进肺癌细胞死亡

目的:研究厚朴酚诱导人非小细胞性肺癌H460细胞的死亡作用并探讨其抗癌作用机制。方法:采用MTT法检测厚朴酚对H460细胞的生长抑制作用,TdT介导dUTP缺口末端标记法(TdT-medi-ated dUTP Nick-End Labeling,TUNEL)法和乳酸脱氢酶(L-Lactate Dehydrogenase,LDH)活力检测法检测细胞凋亡及坏死率,monodansyl-cadaverine(MDC)荧光染色法标记检测细胞自噬情况。结果:厚朴酚可时间依赖性抑制H460肺癌细胞的生长,荧光显微镜下观察厚朴酚作用24h后的细胞出现大量空泡;乳酸脱氢酶活力检测,厚朴酚处理48h后细胞坏死;TUNEL法检测发现,高浓度处理组的细胞很少发生凋亡。结论:厚朴酚主要通过细胞自噬途径而非凋亡途径诱导H460肺癌细胞的死亡。     

基于PI3K/AKT/mTOR信号通路探讨中医药通过活性氧介导的内质网应激调控细胞自噬和凋亡抑制结肠癌转移的研究概况

肿瘤的发生发展需要微环境的保护与支持,自噬和细胞凋亡在结肠癌的复发转移中起到关键作用。PI3K/AKT/mTOR信号通路是自噬经典信号通路,过度的自噬能够诱导自噬细胞的凋亡,而ROS通过改变细胞的内部环境在细胞凋亡和自噬中发挥重要作用,并且能够通过产生ER应激影响ER中的蛋白错误折叠信号,从而影响细胞生长和死亡。因此,探究基于PI3K/AKT/mTOR信号通路,中医药是否可以通过ROS介导的ER应激调控自噬和细胞凋亡从而抑制结肠癌的转移,为临床提供治疗思路。     

抗癌中药单体对肿瘤细胞自噬的调控

自噬是细胞内能量代谢和自我更新的机制,参与细胞诸多生理病理过程,维持机体内稳态。近年来研究发现,自噬与肿瘤的发生发展密切相关,参与调控肿瘤的形成、增殖、转移以及能量代谢等诸多方面。自噬对肿瘤的调控是一个复杂的动态过程,自噬能抑制早期肿瘤的生成,促进晚期肿瘤的发展。目前自噬已成为肿瘤研究领域的新热点,越来越多的研究表明,中草药及其有效成分具有调控肿瘤细胞自噬水平的作用。相对应于自噬在肿瘤发生发展中的复杂角色,抗癌中药有效成分的作用亦具有多面性,或诱导肿瘤细胞发生自噬引起细胞死亡、抑制肿瘤转移;或抑制自噬,增强肿瘤对药物的敏感性;甚至可能在不同肿瘤类型中表现出截然相反的自噬性死亡或保护性自噬作用。目前调控肿瘤自噬水平的中药有效成分研究主要集中在具有抗肿瘤作用的皂苷、生物碱、多酚、黄酮和内酯类化合物,既可以通过诱导细胞自噬达到抗肿瘤的效果,也可以通过抑制细胞自噬发挥抑瘤作用。因此,本文对抗癌中药单体在调节肿瘤细胞自噬方面的研究进展做一综述,有助于研制以自噬为靶点的抗肿瘤药物,为抗肿瘤药物研发提供新方向。     

Graveoline Isolated from Ethanolic Extract of Ruta graveolens Triggers Apoptosis and Autophagy in Skin Melanoma Cells: A Novel Apoptosis‐Independent Autophagic Signaling Pathway

Anti‐cancer drugs generally kill cancer cells by apoptosis but fail to do so when they become resistant and escape apoptosis signals. But these resistant cells can still be killed by autophagy. Therefore, drugs having both apoptotic and autophagic abilities are solicited in effective cancer management. In search of such a drug, we examined the efficacy of graveoline, a bioactive compound isolated from Ruta graveolens on skin melanoma A375 cells through the use of specific signaling cascades and their inhibitors. Cytotoxicity of graveoline was tested by conducting MTT assay. Induction of autophagy and apoptosis was checked. Expression of related proteins and their localization were studied by conducting immunoblot assay and through confocal microscopy, respectively. We found graveoline‐induced Beclin‐1 associated autophagy in A375 cells and 3‐methyladenine, an inhibitor of autophagy did not affect apoptosis. Conversely, caspase inhibitor that blocked apoptosis did not affect autophagic cell death, suggesting thereby that these two were independent events. Use of reactive oxygen species (ROS) scavengers inhibited cell death, but blocking autophagy did not affect graveoline‐induced ROS generation, suggesting that ROS generation ensued autophagy. Thus, graveoline‐induced both apoptotic and autophagic cell death in skin melanoma cells, a desirable quality in effective anti‐cancer drug design. Copyright © 2013 John Wiley & Sons, Ltd.     

Growth arrest and induction of apoptotic and non-apoptotic programmed cell death by, Physalis minima L. chloroform extract in human ovarian carcinoma Caov-3 cells

Ethnopharmacological relevance

The decoction of the whole plant of Physalis minima L. is traditionally consumed to treat cancer. Its anticancer property has been previously verified (using in vitro cytotoxicity assays) against NCI-H23 lung, CORL23 lung and MCF7 breast cancer cell lines but the mechanism underlying the anticancer potency towards ovarian carcinoma cells remain unclear.

Aim of the study

The present study is aimed to systematically determine the cytotoxicity and possible cell death mechanism elicited by the chloroform extract of Physalis minima in human ovarian Caov-3 carcinoma.

Materials and methods

Cytotoxicity of the extract was measured using the methylene blue assay. The mechanism of cell death was determined using four independent methods, namely DeadEnd™ assay to label the DNA fragmentation nuclei cells, RT-PCR analysis to determine the mRNA expression level of three apoptotic genes (c-myc, p53 and caspase-3 genes), Transmission Electron Microscope (TEM) analysis to describe the ultra structural characteristics and annexin V and propidium iodide staining to confirm the types and stages of cell deaths.

Results

Cytotoxicity screening of the extract on Caov-3 cells exhibited concentration- and time-dependent inhibitory effects. A combination of apoptotic and autophagic programmed cell death was detected. The apoptotic characteristic was initially determined by DNA fragmentation followed by the expression of c-myc and p53 genes that was much earlier than caspase-3. Apoptotic ultra structural changes (including clumping and magination of chromatin, blebbing and convolution of nucleus membrane and formation of apoptotic bodies) and autophagy (Type II non-apoptotic programmed cell death) with distinct vacuolated morphology were detected in TEM analysis. The existence of these programmed cell deaths was then corroborated using annexin V and propidium iodide staining.

Conclusions

The chloroform extract of Physalis minima exerted anticancer effect due to a combination of apoptotic and autophagic cell death mechanisms on Caov-3 cells. The induction of these programmed cell deaths was mediated via c-myc, p53 and caspase-3 dependent pathway. The results could provide a valuable insight in cancer therapy.     

7,7'-Dimethoxyagastisflavone-induced apoptotic or autophagic cell death in different cancer cells

7,7'-Dimethoxyagastisflavone (DMGF), a biflavonoid isolated from the needles of Taxus × media cv. Hicksii, was evaluated for its antiproliferative and antineoplastic effects in three human cancer cell lines. Interestingly, DMGF caused cell death via different pathways in different cancer cells. DMGF induced apoptosis, activated caspase-3 activity and changed the mitochondrial membrane potential in HT-29 human colon cancer cells. However, the apoptotic pathway is not the major pathway involved in DMGF-induced cell death in A549 human lung cancer cells and HepG2 human hepatoma cells. Treatment with 3-MA, an inhibitor of autophagy, significantly decreased DMGF-induced cell death in HepG2 and A549 cells, but did not affect DMGF-induced cell death in HT-29 cells. Following DMGF treatment, the HepG2 cells increased expression of LC3B-II, a marker used to monitor autophagy in cells. Thus, DMGF induced apoptotic cell death in HT-29 cells, triggered both apoptotic and autophagic death in A549 cells and induced autophagic cell death in HepG2 cells.     

细胞凋亡机制概述

细胞凋亡是一种重要的生物学过程,是在基因调控下所发生的一系列细胞主动死亡过程。就近几年细胞凋亡信号传递机制、酶学机制以及基因调控机制的研究作一概述。     

自噬对槲皮素诱导人肝癌SMMC-7721细胞死亡的影响

 目的 研究自噬在槲皮素（quercetin,Que）诱导的人肝癌细胞系SMMC-7721死亡中的作用。方法 采用四甲基偶氮唑蓝法测定槲皮素对SMMC-7721细胞的抑制作用;单丹磺酰戊二胺、免疫荧光法观察给药后自噬的发生; 乳酸脱氢酶 (LDH)漏出率、蛋白印迹法观察槲皮素诱导的SMMC-7721细胞死亡的分子机制。结果 槲皮素对SMMC-7721生长有显著抑制作用,呈明显的时间、剂量依赖性; 槲皮素可激活SMMC-7721 细胞的LC3的表达、诱导自噬的发生;乳酸脱氢酶漏出率实验结果表明,在槲皮素给药前用3-甲基腺嘌呤（3-MA）阻断自噬或者氯喹碱化溶酶体,可增强槲皮素对SMMC-7721细胞的细胞毒作用; 蛋白印迹结果显示,槲皮素可使SMMC-7721细胞溶酶体组织蛋白酶B的表达明显增强。结论 槲皮素能明显抑制SMMC-7721 细胞的生长,并诱导其发生自噬;自噬激活能降低槲皮素对SMMC-7721细胞的毒性;自噬的发生与溶酶体酶组织蛋白酶B表达增强相关。     

Biological Effects of the Aqueous Extract of Bridelia grandis Stem Bark on Normal and Neoplastic Human Cells: An In Vitro Preliminary Evaluation

The aim of the work is to investigate the effects of Bridelia grandis (Pierre ex Hutch) stem bark water extract on human HeLa cancer cells and normal monocytes treated in vitro, evaluating the morphological modifications with light and electron microscopy. The phytocomplex obtained from B. grandis caused a significant decrease in the mitotic index of both HeLa cancer cells and normal monocytes. In addition, a reduction of the typical aneuploid‐polyploid pattern has been observed in HeLa cells after treatment. Various alterations at fine structural level, both in neoplastic (HeLa cells) and normal (monocytes) cells have been observed. In particular, electron‐dense cells containing condensed mitochondria, autophagic vacuoles and dense spherical cytoplasmic inclusions have been observed. The results show that B. grandis water extracts have an antiproliferative effect on human cells, with a different effect on neoplastic and normal cells. The antiproliferative effect is accompanied by the appearance of various subcellular alterations. The morphological alterations observed are likely to represent the condition of ‘dark cell’ as a possible preliminary phase towards the autophagic and/or apoptotic cell death. Copyright © 2013 John Wiley & Sons, Ltd.     

细胞凋亡机制概述

细胞凋亡是一种重要的生物学过程,是在基因调控下所发生的一系列细胞主动死亡过程。就近几年细胞凋亡信号传递机制、酶学机制以及基因调控机制的研究作一概述。     

Chinese dragon's blood ethyl acetate extract suppresses gastric cancer progression through induction of apoptosis and autophagy mediated by activation of MAPK and downregulation of the mTOR-Beclin1 signalling cascade

Gastric cancer (GC) is a malignancy with high morbidity and mortality. Chinese dragon's blood is a traditional Chinese medicine derived from the red resin of Dracaena cochinchinensis (Lour.) S. C. Chen. However, the antigastric cancer effect of Chinese dragon's blood has not yet been reported. Herein, we demonstrated that Chinese dragon's blood ethyl acetate extract (CDBEE) suppressed the proliferative and metastatic potential of human gastric cancer MGC-803 and HGC-27 cells. CDBEE suppressed epithelial–mesenchymal transition in MGC-803 and HGC-27 cells. Moreover, CDBEE induced apoptotic and autophagic cell death in MGC-803 and HGC-27 cells. The cytotoxicity of CDBEE in human gastric epithelial GES-1 cells was dramatically weaker than that in human gastric cancer cells. Mechanistically, the activation of the mitogen-activated protein kinase (MAPK) signalling pathway was involved in the growth inhibition of MGC-803 and HGC-27 cells by CDBEE. Additionally, CDBEE-induced autophagic cell death was mediated by downregulation of the mammalian target of rapamycin (mTOR)-Beclin1 signalling cascade and upregulation of the ATG3/ATG7-LC3 signalling cascade. Importantly, CDBEE exhibited potent anti-GC efficacy in vivo without obvious toxicity or side effects. Therefore, CDBEE may be a promising candidate drug for the treatment of gastric cancer, especially for GC patients with aberrant MAPK signalling or mTOR signalling.     

帕金森病理机制常谈常新：多巴胺能神经的氧化性死亡——ferroptosis和oxytosis

黑质致密部多巴胺能神经元的丢失和多巴胺神经递质的释放减少,是临床上导致帕金森病 （Parkinson’s disease,PD）的主要病理机制。在基因和环境的共同影响下,存在多种多巴胺能神经元的死亡机制。目前的研究认为凋亡（apoptosis）、坏死（necrosis）和自噬性死亡（autophagic death）都参与了多巴胺能神经元的死亡,但是这些死亡方式还不足以解释其病理进程和机制。铁死亡（ferroptosis）是一种新近发现的铁依赖性程序性细胞死亡途径,其主要特征为铁离子的负荷增多和大量脂质过氧化物的堆积,这些特征与临床上PD 病人的大脑分子生物学特征高度吻合。此外,有证据显示ferroptosis和三十年前在神经细胞中发现的氧化凋亡（oxytosis）死亡途径在信号调节等方面具有高度相似性,它们都由氧化应激诱导,可能代表着同种形式的程序性细胞死亡。本综述讨论了目前ferroptosis死亡途径在PD中的研究进展,并简述了关于ferroptosis和oxytosis作为同种细胞死亡方式的可能性。阐明多巴胺能神经元死亡方式及其机制可为抗PD药物的研发提供重要的理论依据。