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目的探讨线粒体活性在人脐带间充质干细胞(human umbilical cord mesenchymal stem cells,HUMSCs)条件培养基修复受损成骨细胞中的作用及其机制。方法提取、培养HUMSCs及制作其条件培养基,建立成骨细胞氧化损伤模型。实验分组:无血清DMEM培养基组、晚期氧化蛋白(advanced oxidation protein products,AOPPs)刺激组、常规培养基组、条件培养基组,培养1 h后用流式细胞仪以及Mito Tracker Red分析成骨细胞凋亡率、线粒体活性,并用蛋白-凝胶成像法(western-blot,WB)分析Caspase-3凋亡蛋白表达差异,从而评价HUMSCs条件培养基对遭受氧化损伤的成骨细胞的保护、修复、逆转作用,以及线粒体在其中发挥的作用及其机制。结果HUMSCs条件培养基可以增加氧化应激作用下成骨细胞内线粒体活性;HUMSCs条件培养基可降低成骨细胞凋亡率,减少Caspase-3凋亡蛋白表达。结论HUMSCs条件培养基通过缓解氧化应激(oxidative stress,OS)导致的线粒体功能与结构损伤,并下调Caspase-3凋亡蛋白的表达,抑制OB凋亡。 相似文献
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川芎嗪对大鼠脊髓损伤后线粒体功能的保护作用 总被引:6,自引:0,他引:6
目的探讨川芎嗪对大鼠脊髓损伤(SCI)后线粒体损伤的保护作用及其机制.方法采用Allen'sWD技术制备SCI动物模型,将30只大鼠随机分为假手术组、对照组和治疗组(川芎嗪组),假手术组不损伤脊髓,作为正常对照;对照组于造模前60min和造模后即刻经尾静脉注射生理盐水20mg/kg;治疗组在相同时相注射等量川芎嗪注射液;测定SOD和PLA2活性、MDA浓度及Ca2 -Mg2 -ATP酶活性.结果对照组脊髓线粒体膜PLA2活性、MDA浓度在伤后早期显著升高,SOD活性、Ca2-Mg2 -ATP酶活性明显降低,与假手术组比较差异有显著性;预先应用川芎嗪注射液后,能够明显抑制线粒体 MDA的生成,降低 PLA2活性,提高 SOD活性,并能防止线粒体 Ca2-Mg2 -ATP酶活性的降低.结论川芎嗪能拮抗 SCI后线粒体膜酶的活性变化,其机理可能是提高氧自由基清除能力和抑制脂质过氧化反应. 相似文献
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银杏叶提取物对兔缺血再灌注损伤后视网膜线粒体功能的保护作用 总被引:4,自引:1,他引:4
目的 观察新西兰兔缺血再灌注时视网膜细胞线粒体功能的改变及银杏叶提取物对此改变的影响。方法 30只 (6 0眼 )动物随机分为假手术组 10只 (2 0眼 )、模型对照组10只 (2 0眼 )和银杏叶提取物治疗组 10只 (2 0眼 )。造模后取视网膜组织 ,分离视网膜细胞线粒体。用氧电极法测定线粒体的呼吸功能及还原性辅酶Ⅰ (NADH)氧化酶、琥珀酸氧化酶和细胞色素氧化酶的活性。结果 新西兰兔缺血后视网膜细胞线粒体的呼吸功能有所损伤 ,表现为呼吸控制率、磷氧比和氧化磷酸化效率均较假手术组有不同程度的降低 ,各种氧化酶的活性亦有明显下降。银杏叶提取物组动物的这种改变明显减轻。结论新西兰兔视网膜缺血再灌注后视网膜细胞线粒体的功能明显受损 ,而银杏叶提取物对此损伤具有一定的保护作用。 相似文献
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Apoptotic pathways of macrophages within osteolytic interface membrane in periprosthestic osteolysis after total hip replacement 下载免费PDF全文
Guoyin Liu Yong Zhang Naicheng Liu Jiangning Chen Jianmin Chen Junfeng Zhang Jianning Zhao 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2017,125(6):565-578
Macrophage apoptosis in interface membrane, which occurs through either death receptor, mitochondrion, or endoplasmic reticulum (ER) stress pathways, has been suggested to play an important role in promoting osteolysis. However, how and why macrophage apoptosis originates and the correlation among these apoptotic pathways is not yet clear. The objective of this study was to identify the apoptotic mechanism of macrophages, and to explore the relationship between the apoptotic pathways and progression of osteolysis. Transmission electron microscopy (TEM) was utilized to analyze the tissue ultrastructure of wear particles, and in situ apoptotic macrophage identification was performed by TUNEL staining. We analyzed the expression of the key biomarkers of apoptotic pathways via immunohistochemistry and Western blotting. Our results demonstrated that the majority of wear particles within osteolytic interface membrane was in the 30–60 nm range, and that macrophage apoptotic ratio increased along with osteolysis progression. Normal hip dysplasia and mechanical loosening of tissues showed low expression levels of biomarkers for ER stress (Ca2+, JNK, cleaved Caspase‐4, IRE1‐α, Grp78/Bip, and CHOP), mitochondrion (Bcl‐2, Bax, and Cytochrome c), and death receptor (Fas and cleaved Caspase‐8) pathways, while osteolytic interface membrane tissues expressed high levels of these biomarkers. In addition, we found that the ER stress intensity was in complete conformity with mitochondrial dysfunction and was consistent with the results of death receptor activation. Thus, our findings suggested that wear particles generated at implant interface can accelerate macrophage apoptosis through changes in apoptotic pathways and ultimately aggravate the symptom of osteolysis. These data represent a preferential apoptotic signaling pathway of macrophages as specific target points for the prevention and therapeutic modulation of periprosthetic osteolysis. 相似文献
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Elikanah Olusayo Adegoke Samson Olugbenga Adeniran Yue Zeng Xue Wang Hao Wang Chen Wang Han Zhang Peng Zheng Guixue Zhang 《Journal of applied toxicology : JAT》2019,39(6):832-843
This study investigated the pharmacological inhibition of the toll‐like receptor 4 (TLR4) genes as a measure to attenuate microcystin‐LR (MC‐LR) reproductive toxicity. Bovine Sertoli cells were pretreated with TLR4‐IN‐C34 (C34) for 1 hour. Thereafter the pretreated and non‐pretreated Sertoli cells were cultured in medium containing 10% heat‐activated fetal bovine serum + 80 μg/L MC‐LR for 24 hours to assess the ability of TLR4‐IN‐C34 to attenuate the toxic effects of MC‐LR. The results showed that TLR4‐IN‐C34 inhibited MC‐LR‐induced mitochondria membrane damage, mitophagy and downregulation of blood‐testis barrier constituent proteins via TLR4/nuclear factor‐kappaB and mitochondria‐mediated apoptosis signaling pathway blockage. The downregulation of the mitochondria electron transport chain, energy production and DNA replication related genes (mt‐ND2, COX‐1, COX‐2, ACAT, mtTFA) and upregulation of inflammatory cytokines (interleukin [IL]‐6, tumor necrosis factor‐α, IL‐1β, interferon‐γ, IL‐4, IL‐10, IL‐13 and transforming growth factor β1) were modulated by TLR4‐IN‐C34. Taken together, we conclude that TLR4‐IN‐C34 inhibits MC‐LR‐related disruption of mitochondria membrane, mitophagy and downregulation of blood‐testis barrier proteins of the bovine Sertoli cell via cytochrome c release and TLR4 signaling blockage. 相似文献
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David R. Lynch MD PhD Massimo Pandolfo MD Jorg B. Schulz MD Susan Perlman MD Martin B. Delatycki MD PhD R. Mark Payne MD Robert Shaddy MD Kenneth H. Fischbeck MD Jennifer Farmer MS Paul Kantor MD Subha V. Raman MD Lisa Hunegs MSW MPH Joanne Odenkirchen MPH Kristy Miller MPH Petra Kaufmann MD MSC 《Movement disorders》2013,28(2):190-195
To reduce study start‐up time, increase data sharing, and assist investigators conducting clinical studies, the National Institute of Neurological Disorders and Stroke embarked on an initiative to create common data elements for neuroscience clinical research. The Common Data Element Team developed general common data elements, which are commonly collected in clinical studies regardless of therapeutic area, such as demographics. In the present project, we applied such approaches to data collection in Friedreich's ataxia (FRDA), a neurological disorder that involves multiple organ systems. To develop FRDA common data elements, FRDA experts formed a working group and subgroups to define elements in the following: ataxia and performance measures; biomarkers; cardiac and other clinical outcomes; and demographics, laboratory tests, and medical history. The basic development process included identification of international experts in FRDA clinical research, meeting by teleconference to develop a draft of standardized common data elements recommendations, vetting of recommendations across the subgroups, and dissemination of recommendations to the research community for public comment. The full recommendations were published online in September 2011 at http://www.commondataelements.ninds.nih.gov/FA.aspx . The subgroups′ recommendations are classified as core, supplemental, or exploratory. Template case report forms were created for many of the core tests. The present set of data elements should ideally lead to decreased initiation time for clinical research studies and greater ability to compare and analyze data across studies. Their incorporation into new, ongoing studies will be assessed in an ongoing fashion to define their utility in FRDA. © 2012 Movement Disorder Society 相似文献
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目的 研究芒柄花素磺酸钠(sodium formononetin-3ʹ-sulphonate,Sul-F)调控线粒体凋亡通路改善脑缺血再灌注损伤的作用机制。方法 建立大鼠脑缺血再灌注损伤模型,随机分为假手术组、模型组、依达拉奉(3 mg/kg)组和Sul-F高、低剂量(80、40 mg/kg)组,分别于再灌注0、12 h尾iv药物干预,假手术组和模型组给予等体积的生理盐水。再灌注24 h后,Zea Longa评分法评估神经功能;2,3,5-氯化三苯基四氮唑(2,3,5-triphenyltetrazolium chloride,TTC)染色测定脑梗死体积;苏木素-伊红(hematoxylin-eosin,HE)染色观察脑缺血半暗带病理变化;原位末端标记(TdT-mediated dUTP nick end labeling,TUNEL)染色检测脑缺血半暗带细胞凋亡情况;JC-1探针流式细胞术检测脑缺血半暗带线粒体膜电位水平;透射电镜观察脑组织超微结构;ELISA法检测脑缺血半暗带丙二醛(malondialdehyde,MDA)水平及超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活性;qRT-PCR和Western blotting分别检测脑缺血半暗带B淋巴细胞瘤-2(B-cell lymphoma-2,Bcl-2)、Bcl-2相关X蛋白(Bcl-2 associated X protein,Bax)和半胱氨酸天冬氨酸蛋白酶-3(cystein-asparate protease-3,Caspase-3)mRNA和蛋白表达。结果 与模型组比较,Sul-F高剂量组大鼠神经功能评分显著降低(P<0.01),脑梗死体积显著减小(P<0.05),脑缺血半暗带病理损伤减轻,细胞凋亡显著减少(P<0.01),线粒体膜电位的去极化显著逆转(P<0.05),线粒体嵴更加清晰、自噬现象更少见,MDA含量显著降低(P<0.01),SOD和GSH-Px活力显著升高(P<0.05、0.01);Bcl-2表达显著增加(P<0.01),Bax和Caspase-3表达显著减低(P<0.01)。结论 Sul-F通过调控线粒体凋亡相关基因Bcl-2/Bax平衡,改善线粒体氧化应激水平,减轻脑缺血再灌注损伤。 相似文献
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