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1.
Ovarian cancer is one of the leading causes of cancer-related death among women worldwide and accounts for 4% of all cancer cases in female patients. To date, ovarian cancer has the poorest prognosis among all types of gynecological cancer; thus, it is necessary to identify prospective therapeutic options. Previous studies have demonstrated the involvement of reactive oxygen species (ROS) in the cytotoxicity of various anticancer drugs against several types of carcinoma, including ovarian cancer. The present study aimed to investigate the anticancer effects of Siomycin A, a thiopeptide antibiotic, on the ovarian cancer cell lines PA1 and OVCAR3. To determine the viability of these cells following exposure to Siomycin A, the MTT assay was used, and apoptosis was determined by ELISA. In addition, mitochondrial membrane potential was determined by JC1 staining, and cellular ROS levels were assessed by dichlorodihydrofluorescein diacetate staining in the presence and absence of antioxidant NAC. The subsequent levels of antioxidant enzymes and glutathione were also determined following Siomycin A treatment in the two cell lines. A combination study with Siomycin A and cisplatin indicated enhanced efficiency of the drugs on ovarian cancer cell viability. The results of the present study also demonstrated that Siomycin A induced ROS production, inhibited the major antioxidant enzymes, including catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase and intracellular GSH in PA1 and OVCAR3 cells, and inhibited the cell viability with an IC50 of ~5.0 and 2.5 µM after 72 h respectively compared with the untreated controls. Additionally, the Siomycin A-induced ROS production further targeted apoptotic cell death by impairing the mitochondrial membrane potential and modulating the levels of pro- and antiapoptotic proteins compared with those in the corresponding control groups. The administration of the antioxidant N-acetylcysteine significantly abrogated the cytotoxic effects of Siomycin A. In conclusion, the results of the present study demonstrated the role of ROS in Siomycin A-mediated cytotoxicity in ovarian cancer cells.  相似文献   
2.
王锋  张超  郑栓 《中草药》2021,52(24):7473-7483
目的 成功制备雷公藤甲素(3-丙羧基)三苯基溴化膦(TPP)-聚乙二醇-b-聚己内脂(PEG-PCL)脂质体(Tr@TPP/Lip),评价其靶向性及促肝肿瘤细胞凋亡效果。方法 采用正交试验优选Tr@TPP/Lip的制备工艺,再研究该载药系统的粒径、Zeta电位、载药量、包封率和多分散系数及透射电镜微观形态,评价Tr@TPP/Lip的稳定性、溶血性、释放情况;采用荧光试验,研究脂质体与肝肿瘤细胞的融合情况、线粒体靶向性和肝脏靶向性;在等剂量给药条件下,评价Tr@TPP/Lip促肝癌细胞凋亡效果。结果 正交试验优选的Tr@TPP/Lip粒径为(113.5±17.6)nm,Zeta电位(12.6±0.7)mV,包封率为(71.3±3.2)%,载药量为(3.9±1.1)%,多分散系数为0.12±0.04;透射电子显微镜图片显示Tr@TPP/Lip呈规则圆球形,该脂质体稳定性良好,具有较小的溶血率和良好的缓释药物性能;荧光试验结果显示,TPP阳离子能促进脂质体与肿瘤细胞的融合,并靶向线粒体,还能提高药物在肝肿瘤部位的靶向和滞留效果;细胞药效结果显示,Tr@TPP/Lip具有良好的促肝肿瘤细胞凋亡效果,能明显降低线粒体膜Zeta电位、增加细胞内活性氧水平和Caspase-3的释放,显著增加促凋亡蛋白Bcl-2、减少抗凋亡Bax蛋白的表达,这些细胞凋亡试验结果均明显优于雷公藤甲素普通脂质体和雷公藤甲素。结论 Tr@TPP/Lip具有较好的线粒体靶向功能,能增强药物促肝肿瘤细胞凋亡效果。  相似文献   
3.
目的 探讨广州市白纹伊蚊不同地理种群的遗传多样性、遗传分化和系统发育关系。方法 本实验于2020年9月至2020年11月期间,采集广州市11个行政区的共计15个白纹伊蚊种群。单只蚊虫提取基因组DNA,通过PCR法扩增COI基因序列并测序,获得的序列在GenBank上经过BLAST比对。BioEdit 7.2软件观察序列峰图。MEGA X软件对齐序列,分析碱基组成,构建系统发育树(NJ法)。DNAsp 6.12软件分析位点多态性,单倍型及其多样性,进行错配分布分析。Arlequin 3.5软件进行分子变异分析、进行中性检验。DAMBE 7.2软件分析序列的系统发育信号。 PopART 1.7软件构建单倍型网络图(Median joining法)。结果 广州市15个白纹伊蚊种群共获得642条序列,其长度为603 bp。A碱基加T碱基平均含量是67.5%,符合线粒体DNA的AT偏向性。单倍型分析共检出45种单倍型,其中单倍型1为优势单倍型。中性检验表明广州市部分种群不符合中性理论,但大部分种群都经历过种群扩张,而错配分布却表明仅有少部分种群经历过种群扩张。Mantel检验表明15个白纹伊蚊种群不存在地理隔离现象。种群遗传分化显示各种群间交流较频繁,且种群间的遗传分化很低,差异更多来自于个体间。结论 广州市的白纹伊蚊种群间基因交流较频繁,遗传分化小,遗传多样性偏低。这可能使不同地理种群的白纹伊蚊具有相似的媒介能力。  相似文献   
4.
目的:探究Src羧基端激酶结合蛋白(csk-binding protein,CBP)在人肺癌组织中的表达水平,及其对线粒体分裂和自然杀伤(natural killer,NK)细胞杀伤肺癌细胞活性的影响。方法:免疫组织化学染色和实时荧光定量PCR(qRT-PCR)检测肺癌组织及癌旁组织中CBP的表达;含CBP慢病毒感染人肺癌细胞株A549,通过荧光倒置显微镜、qRT-PCR 和Western blot检测细胞感染效果;CCK-8法检测各组A549细胞活性,Mito-Tracker染色观察各组A549细胞内线粒体形态和长度变化,Western blot检测各组A549细胞线粒体动态相关蛋白Mfn1、Mfn2、Drp1的表达,免疫荧光染色检测各组A549细胞内细胞色素C(Cyt C)的表达,流式细胞术检测各组A549细胞凋亡情况;从人外周血单个核细胞(peripheral blood mononuclear cell,PBMC)中分离NK细胞并进行鉴定,乳酸脱氢酶释放实验检测NK细胞对各组A549细胞的杀伤率。结果:肺癌组织中CBP的表达水平较癌旁组织中明显下降(P<0.01);感染CBP过表达慢病毒的A549细胞中CBP mRNA和蛋白的相对表达量均升高,培养48 h、72 h、96 h后细胞增殖活性下降,线粒体呈椭圆状或短杆状,长度明显缩短,线粒体分裂相关蛋白Mfn1、Mfn2蛋白表达减少,Drp1蛋白表达增加,有大量Cyt C从线粒体释放,细胞凋亡率升高,同时NK细胞对A549细胞的杀伤率明显提高,差异均具有统计学意义(P<0.01);而在使用线粒体分裂蛋白抑制剂Mdivi-1预先处理A549细胞后再感染CBP过表达慢病毒,线粒体分裂受到抑制,Mfn1、Mfn2蛋白表达增加,Drp1蛋白表达减少,Cyt C释放减少,细胞凋亡率降低,NK细胞对A549细胞的杀伤率也受到抑制,差异均具有统计学意义(P<0.01)。结论:CBP在人肺癌组织中低表达,在A549细胞中过表达CBP能够促进线粒体分裂与细胞凋亡,并提高NK细胞对A549细胞的杀伤率。  相似文献   
5.
线粒体是多细胞生命不可缺少的组成部分,通过裂变和融合进行形态上的变化和空间上的重新排列以适应细胞的需求,维持能量平衡。线粒体的这种控制其自身数量、大小、形状和在细胞内的分布特征被称为线粒体动力学。正常情况下,线粒体融合-裂变是平衡的,当细胞早期受到应激时,受损的线粒体首先通过裂变和融合来维持其功能的正常运行。线粒体功能异常可能与细胞的衰老和凋亡密切相关,因此,本文就线粒体动力学包括线粒体裂变和融合在常见眼科疾病中的研究进展进行综述。  相似文献   
6.
目的 观察逍遥散对抑郁大鼠行为学及其骨骼肌线粒体超微结构和功能的影响。方法 将SD大鼠随机分为对照组、模型组、文拉法辛(给予盐酸文拉法辛胶囊35 mg·kg-1)组和逍遥散(生药21.2 g·kg-1)组,每组12只。除对照组外,采用孤养结合28 d慢性不可预知温和应激(CUMS)建立抑郁模型,造模同时给药,每天1次,连续给药28 d。对大鼠的体质量、糖水偏爱率及旷场实验中的直立次数、穿越格数进行评价;在透射电镜下观察骨骼肌线粒体结构,试剂盒法检测骨骼肌线粒体中腺嘌呤核苷三磷酸(ATP)和线粒体呼吸链复合体(MRCC)I、Ⅱ、III、IV、V水平。结果 与对照组比较,模型组大鼠体质量增长显著减缓、糖水偏爱率、直立次数和穿越格数显著减少(P<0.05、0.01);与模型组比较,文拉法辛组和逍遥散组造模第3、4周大鼠体质量显著增加(P<0.05、0.01),文拉法辛组造模第2、3周和逍遥散组造模第1~4周大鼠糖水偏爱率显著升高(P<0.05、0.01),文拉法辛组造模第1、3、4周和逍遥散组造模第3、4周大鼠直立次数显著增加(P<0.05、0.01),文拉法辛组造模第1~4周和逍遥散组造模第3、4周大鼠穿越格数显著增多(P<0.05、0.01)。透射电镜结果发现,与对照组比较,模型组大鼠骨骼肌线粒体数目减少、空泡变性及形态肿胀;与模型组比较,文拉法辛组和逍遥散组的大鼠骨骼肌线粒体结构和功能损伤较轻。与对照组比较,模型组大鼠骨骼肌中的MRCC Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ和ATP水平显著下降(P<0.05、0.01);与模型组比较,文拉法辛组MRCC Ⅰ、Ⅱ、Ⅳ水平,逍遥散组MRCC Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ和ATP水平均显著升高(P<0.05、0.01)。结论 抑郁大鼠出现骨骼肌线粒体结构和功能损伤,可能是引起抑郁大鼠产生疲劳的原因之一;逍遥散可通过保护骨骼肌线粒体结构和功能进而改善大鼠抑郁症状。  相似文献   
7.
Objective: The main pathological change of Parkinson’s disease (PD) is progressive degeneration and necrosis of dopaminergic neurons in the midbrain, forming a Lewy body in many of the remaining neurons. Studies have found that in transgenic Drosophila, mutations in the PTEN-inducible kinase 1 (PINK1) gene may cause indirect flight muscle defects in Drosophila, and mitochondrial structural dysfunction as well.

Methods: In this study, Wnt4 gene overexpression and knockdown were performed in PINK1 mutant PD transgenic Drosophila, and the protective effect of Wnt4 gene on PD transgenic Drosophila and its possible mechanism were explored. The Wnt4 gene was screened in the previous experiment; And by using the PD transgenic Drosophila model of the MHC-Gal4/UAS system, the PINK1 gene could be specifically activated in the Drosophila muscle tissue.

Results: In PINK1 mutation transgenic fruit flies, the Wnt4 gene to study its implication on PD transgenic fruit flies’ wing normality and flight ability. We found that overexpression of Wnt4 gene significantly reduced abnormality rate of PD transgenic Drosophila and improved its flight ability, and then, increased ATP concentration, enhanced mitochondrial membrane potential and normalized mitochondrial morphology were found. All of these findings suggested Wnt4 gene may have a protective effect on PD transgenic fruit flies. Furthermore, in Wnt4 gene overexpression PD transgenic Drosophila, down-regulation autophagy and apoptosis-related proteins Ref(2)P, Pro-Caspase3, and up-regulation of Beclin1, Atg8a, Bcl2 protein were confirmed by Western Blotting.

Conclusion: The results imply that the restoring of mitochondrial function though Wnt4 gene overexpression in the PINK1 mutant transgenic Drosophila may be related to autophagy and/or apoptosis.  相似文献   

8.
目的:探讨阿霉素(ADR)诱导人肾小管上皮细胞(HK-2)发生氧化损伤后,紫苏叶水提取物(PFAE)对其细胞活性、氧化损伤标记物及细胞凋亡等关键因子的影响。方法:ADR刺激HK-2细胞建立损伤模型,使用N-乙酰半胱氨酸(NAC)或不同浓度PFAE(5,15,45 g·L~(-1))干预后,采用细胞增殖/毒性检测(CCK-8)法检测细胞存活率,结合光镜下细胞形态变化,筛选出PFAE保护细胞的最佳浓度。后续实验分为6组:空白组,ADR(0.05 g·L~(-1))组,PFAE(15 g·L~(-1))组,ADR+PFAE(0.05+15)g·L~(-1)组,NAC(0.81 g·L~(-1))组,ADR+NAC(0.05+81)g·L~(-1)组。检测细胞匀浆中的丙二醛(MDA),超氧化物歧化酶(SOD)和细胞总抗氧化能力,2',7'-二氯荧光黄双乙酸盐(DCFH-DA)荧光探针检测细胞内活性氧(ROS)水平,流式细胞术及脱氧核糖核苷酸末端转移酶(TUNEL)染色法检测细胞凋亡率,蛋白免疫印迹法(Western blot)检测细胞线粒体凋亡相关蛋白B淋巴细胞瘤-2基因(Bcl-2),Bcl-2相关X蛋白(Bax),半胱氨酸天冬氨酸蛋白酶9和3(Caspase-9,Caspase-3),聚腺苷二磷酸-核糖聚合酶(PARP)包括其剪切体的表达,及丝裂原活化蛋白激酶(MAPK)信号转导通路中p38丝裂素活化蛋白激酶(p38 MAPK),细胞外信号调节激酶(ERK),c-Jun氨基端激酶(JNK)及其磷酸化蛋白的表达。结果:与空白组比较,ADR组的细胞活性显著降低(P0.01),与ADR组比较,5,15 g·L~(-1)的PFAE和NAC能促进细胞的增殖(P0.01)。与空白组比较,ADR组抗氧化能力和SOD水平显著降低(P0.01),MDA和ROS的水平显著增高(P0.01),与ADR组比较,ADR+PFAE组和ADR+NAC组抗氧化能力和SOD水平显著升高(P0.01),MDA和ROS的水平显著下降(P0.01)。与空白组比较,ADR组细胞凋亡率上升(P0.01),凋亡相关蛋白Bax/Bcl-2,cleaved Caspase-9/Caspase-9,cleaved Caspase-3/Caspase-3,cleaved PARP/PARP水平显著上升(P0.01),MAPKs通路中的p38 MAPK,ERK和JNK的磷酸化蛋白表达明显增高(P0.05,P0.01);与ADR组比较,PFAE或NAC干预后减轻了细胞凋亡率,降低了凋亡蛋白的相对比值,并且抑制了MAPK信号通路中p38 MAPK,ERK蛋白的磷酸化(P0.01),但对磷酸化的JNK蛋白表达无影响。结论:PFAE可以减轻ADR诱导的HK-2细胞氧化损伤,并发挥抗氧化作用,通过线粒体凋亡途径和ERK/p38 MAPK信号通路来抑制细胞凋亡。  相似文献   
9.
Glutaric Aciduria type I (GA-I) is caused by mutations in the GCDH gene. Its deficiency results in accumulation of the key metabolites glutaric acid (GA) and 3-hydroxyglutaric acid (3-OHGA) in body tissues and fluids. Present knowledge on the neuropathogenesis of GA-I suggests that GA and 3-OHGA have toxic properties on the developing brain.We analyzed morphological and biochemical features of 3D brain cell aggregates issued from Gcdh?/? mice at two different developmental stages, day-in-vitro (DIV) 8 and 14, corresponding to the neonatal period and early childhood. We also induced a metabolic stress by exposing the aggregates to 10 mM l-lysine (Lys).Significant amounts of GA and 3-OHGA were detected in Gcdh?/? aggregates and their culture media. Ammonium was significantly increased in culture media of Gcdh?/? aggregates at the early developmental stage. Concentrations of GA, 3-OHGA and ammonium increased significantly after exposure to Lys. Gcdh?/? aggregates manifested morphological alterations of all brain cell types at DIV 8 while at DIV 14 they were only visible after exposure to Lys. Several chemokine levels were significantly decreased in culture media of Gcdh?/? aggregates at DIV 14 and after exposure to Lys at DIV 8.This new in vitro model for brain damage in GA-I mimics well in vivo conditions. As seen previously in WT aggregates exposed to 3-OHGA, we confirmed a significant ammonium production by immature Gcdh?/? brain cells. We described for the first time a decrease of chemokines in Gcdh?/? culture media which might contribute to brain cell injury in GA-I.  相似文献   
10.
The growing usage of nanoscale zerovalent iron particles (nZVI) in the remediation of soil, ground/surface water has elicited large‐scale environmental release triggering human exposure. The size of nanomaterials is a key regulator of toxicity. However, the effect of a variable size of nZVI on genotoxicity is unexplored in human cells. To the best of our knowledge, in this study, the cytotoxic, genotoxic and hemolytic potential of nZVI‐1 (15 nm) and nZVI‐2 (50 nm) at concentrations of 5, 10 and 20 μg/mL was evaluated for the first time in human lymphocytes and erythrocytes treated for 3 hours. In erythrocytes, spherocytosis and echinocytosis occurred upon exposure to nZVI‐1 and nZVI‐2, respectively, leading to hemolysis. Lymphocytes treated with 20 μg/mL nZVI‐2 and 10 μg/mL nZVI‐1, incurred maximum DNA damage, although nZVI‐2 induced higher cyto‐genotoxicity than nZVI‐1. This can be attributed to higher Fe ion dissolution and time/concentration‐dependent colloidal destabilization (lower zeta potential) of nZVI‐2. Although nZVI‐1 showed higher uptake, its lower genotoxicity can be due to lesser Fe content, Fe ion dissolution and superior colloidal stability (higher zeta potential) compared with nZVI‐2. Substantial accumulation of Ca2+, superoxide anions, hydroxyl radicals and H2O2 leading to mitochondrial impairment and altered antioxidant enzyme activity was noted at the same concentrations. Pre‐treatment with N‐acetyl‐cysteine modulated these parameters indicating the indirect action of reactive oxygen species in nZVI‐induced DNA damage. The morphology of diffused nuclei implied the possible onset of apoptotic cell death. These results validate the synergistic role of size, ion dissolution, colloidal stability and reactive oxygen species on cyto‐genotoxicity of nZVI and unlock further prospects in its environmental nano‐safety evaluation.  相似文献   
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