间充质干细胞来源外泌体促心肌梗死血管新生及其机制研究进展

血管新生(angiogenesis)是机体内一个复杂的生理学和病理学过程,是治疗缺血性疾病的重要措施。大量实验研究已表明间充质干细胞(mesenchymal stem cells, MSCs)等干细胞移植可促进心肌梗死后血管新生,近期研究证实这一作用可能主要通过分泌外泌体形式介导。外泌体(exosome)通过传递与血管新生相关微RNA(microRNA, mi RNA)或蛋白质等生物活性物质,调控靶器官中与血管新生相关通路的基因表达,提高内皮细胞在缺血缺氧环境下的存活、迁移、成管能力,促进心肌梗死区域血管新生。通过基因修饰手段增强外泌体介导的心脏修复作用,以及将外泌体与生物活性肽结合形成工程外泌体来靶向缺血心肌治疗,是目前外泌体在心血管领域的热点研究方向。本文结合近年外泌体研究的相关文献,就MSCs来源外泌体促进心肌梗死血管新生的具体机制及现状研究作一综述。     

脂肪间充质干细胞外泌体在糖尿病肾病中的保护作用及其机制

糖尿病肾病(diabetic nephropathy,DN)是导致终末期肾脏疾病的主要原因,也是发生心血管疾病的一个独立风险因素,严重影响人类健康.缓解并治疗DN已经成为当前终末期肾脏疾病的重要研究方向.脂肪间充质干细胞(adipose-derived stem celljs,ADSCs)是一种来自脂肪组织的成体干细胞...     

间充质干细胞外泌体在糖尿病并发症中的作用

外泌体是一类由各种细胞分泌的直径40～100 nm的胞外囊泡,由细胞内复杂的产生机制生成后分泌到胞外,由于其内含蛋白质、脂质和核酸,所以在细胞间的通讯上发挥着巨大作用。近年来,各种细胞来源的外泌体与疾病治疗的相关性研究有了许多进展,特别是间充质干细胞外泌体,拥有强大的免疫调节能力和组织修复能力,因此其在糖尿病并发症的治疗上拥有巨大的潜力。本文将对外泌体的来源、间充质干细胞和外泌体的生物学特性、组织修复特性及其在糖尿病肾病、糖尿病中枢神经病变、糖尿病血管病变及糖尿病皮肤病变中的治疗潜力作一综述。     

大熊猫脐带间充质干细胞外泌体的分离鉴定及miRNAs富集分析

大熊猫脐带间充质干细胞(Umbilical cord mesenchymal stem cells, UC-MSCs)通过旁分泌所释放的外泌体在大熊猫保健与疾病治疗方面具有一定的应用前景。本研究旨在建立大熊猫UC-MSCs外泌体分离方法,开展生物学特征分析和分子鉴定,并研究UC-MSCs外泌体中miRNAs的种类与功能。采用超速离心法从大熊猫UCMSCs培养上清中成功分离外泌体,通过透射电子显微镜进行形态学观察,纳米颗粒跟踪分析仪检测粒径大小,蛋白免疫印迹法检测特异性分子标记表达。采用Small RNA测序技术对UC-MSCs外泌体中的miRNAs进行鉴定,并对其靶基因进行了预测与功能分析。结果显示,大熊猫UC-MSCs外泌体呈圆形杯托状结构,直径为(79.15±4.81) nm,外泌体标志蛋白CD81与TSG101呈阳性表达而CALNEXIN呈阴性表达。大熊猫UC-MSCs外泌体中的miRNA主要为miR-148-3p (30.28%)与miR-21-5p (21.72%)。本研究首次从大熊猫UC-MSCs培养上清中分离出外泌体,并对其所含的miRNAs进行富集分析及功能预测,为大熊...     

间充质干细胞来源外泌体在骨关节炎治疗中的作用

骨关节炎(OA)是最常见的慢性退行性骨关节疾病,目前对骨关节炎的治疗还没有特效疗法。间充质干细胞(MSC)对软骨修复有较好的疗效,间充质干细胞来源外泌体可能在这一治疗过程中发挥重要作用。外泌体是细胞间的通讯载体,能在细胞间传递生物活性脂质、核酸以及蛋白质等生物活性分子对骨关节炎产生一定影响。本文就探讨间充质干细胞来源的外泌体治疗骨关节炎过程中的作用机制与可行性做出综述。     

脂肪间充质干细胞来源外泌体的功能

外泌体是细胞外膜质纳米囊泡,将蛋白质、核酸(DNA和RNA)转运到靶细胞中,介导局部和系统的细胞间通信,从而改变受体细胞的行为.这些小泡在许多生物功能中发挥重要作用,如脂肪合成、免疫调节、神经再生和肿瘤调节等.脂肪间充质干细胞目前被认为是细胞治疗和再生医学领域中一种功能丰富的工具,可产生和分泌多种外泌体,继承细胞的多种...     

人嗅觉黏膜间充质干细胞来源的外泌体促进内皮细胞的血管生成

外泌体作为是细胞旁分泌的重要介质,在促血管形成方面有重要作用。在我们前期研究中,已经成功从嗅黏膜间充质干细胞（olfactory mucosa mesenchymal stem cells,OM-MSCs）分离、鉴定了其外泌体,然而,OM-MSCs源外泌体对血管生成的影响尚不清楚。本研究旨在探讨OM-MSCs来源外泌体对内皮细胞血管生成能力的影响。采用PKH67 荧光标记OM-MSCs源外泌体,与人脑微血管内皮细胞（human brain microvessel endothelial cells, HBMECs) 共培养,观察 OM-MSCs外泌体能否进入 HBMECs。采用CCK-8法、Transwell 迁移实验和小管实验,观察 OM-MSCs外泌体对 HBMECs增殖、迁移及管状结构形成的影响。采用基质胶塞实验及CD31免疫荧光,观察OM-MSCs外泌体在体内对血管生成的影响。上述研究均以等量 PBS 作为对照。结果提示,OM-MSCs外泌体可被HBMECs 摄取。CCK-8 法检测显示,在处理1、2、3、4、5 d各时间点,实验组细胞增殖均优于对照组（1.32±0.14 vs. 0.98±0.04, 1.36±0.14 vs.1.04±0.06, 1.75±0.18 vs.1.33±0.11, 2.16±0.11 vs.1.50±0.19, 2.71±0.11 vs. 1.81±0.20, P<0.01）。Transwell 实验结果显示,实验组跨膜迁移细胞吸光度值较对照组显著增多（1.12±0.05 vs.0.02±0.02, P<0.05）。在体外小管实验中,从节点、交叉点、网眼数、血管分支数和总长度5个方面,实验组均高于空白对照组（374.33±127.74 vs. 193.33±44.79, 104.56±33.07 vs. 54.33±11.65, 20.11±11.20 vs. 7.56±3.64, 81.67±19.07 vs. 57.00±13.02, 11466.22±2781.03 vs. 8544.00±1848.61, P<0.05）;在体内实验中,实验组成血管及CD31阳性率（%）亦显著高于对照组（85.00±5.57 vs.8.00±2.08, P<0.05）。本研究表明：OM-MSCs外泌体可促进 HBMECs 增殖、迁移及管样结构形成,提示OM-MSCs外泌体可促进血管新生。     

人嗅觉黏膜间充质干细胞来源的外泌体促进内皮细胞的血管生成

外泌体作为是细胞旁分泌的重要介质,在促血管形成方面有重要作用。在我们前期研究中,已经成功从嗅黏膜间充质干细胞（olfactory mucosa mesenchymal stem cells,OM-MSCs）分离、鉴定了其外泌体,然而,OM-MSCs源外泌体对血管生成的影响尚不清楚。本研究旨在探讨OM-MSCs来源外泌体对内皮细胞血管生成能力的影响。采用PKH67 荧光标记OM-MSCs源外泌体,与人脑微血管内皮细胞（human brain microvessel endothelial cells, HBMECs) 共培养,观察 OM-MSCs外泌体能否进入 HBMECs。采用CCK-8法、Transwell 迁移实验和小管实验,观察 OM-MSCs外泌体对 HBMECs增殖、迁移及管状结构形成的影响。采用基质胶塞实验及CD31免疫荧光,观察OM-MSCs外泌体在体内对血管生成的影响。上述研究均以等量 PBS 作为对照。结果提示,OM-MSCs外泌体可被HBMECs 摄取。CCK-8 法检测显示,在处理1、2、3、4、5 d各时间点,实验组细胞增殖均优于对照组（1.32±0.14 vs. 0.98±0.04, 1.36±0.14 vs.1.04±0.06, 1.75±0.18 vs.1.33±0.11, 2.16±0.11 vs.1.50±0.19, 2.71±0.11 vs. 1.81±0.20, P<0.01）。Transwell 实验结果显示,实验组跨膜迁移细胞吸光度值较对照组显著增多（1.12±0.05 vs.0.02±0.02, P<0.05）。在体外小管实验中,从节点、交叉点、网眼数、血管分支数和总长度5个方面,实验组均高于空白对照组（374.33±127.74 vs. 193.33±44.79, 104.56±33.07 vs. 54.33±11.65, 20.11±11.20 vs. 7.56±3.64, 81.67±19.07 vs. 57.00±13.02, 11466.22±2781.03 vs. 8544.00±1848.61, P<0.05）;在体内实验中,实验组成血管及CD31阳性率（%）亦显著高于对照组（85.00±5.57 vs.8.00±2.08, P<0.05）。本研究表明：OM-MSCs外泌体可促进 HBMECs 增殖、迁移及管样结构形成,提示OM-MSCs外泌体可促进血管新生。     

间充质干细胞来源外泌体在膝骨关节炎微环境中的作用

骨关节炎是一种涉及所有关节成分（包括关节软骨、软骨下骨、滑膜、韧带、关节囊和关节周围肌肉）的关节退行性疾病，会导致严重的残疾，其中最常见的是膝骨关节炎（knee osteoarthritis，KOA）。外泌体是一种由不同细胞分泌的直径为40~100 nm的胞外囊泡，可以传递DNA、微小RNA、mRNA、蛋白质等多种物质，并通过多种方式进行细胞间的信息传递和功能调节。间充质干细胞（mesenchymal stem cells，MSCs）可以从骨髓、脂肪、滑膜及外周血等组织分离，是一类具有多向分化潜能的祖细胞，以干细胞为基础的疗法可以修复软骨损伤，对抗KOA的发展，间充质干细胞能够分泌多种营养因子来调节受损的微环境，其中间充质干细胞来源的外泌体被认为在KOA炎症反应及软骨细胞代谢中发挥着重要的作用，其能够调节膝骨关节微环境中B细胞、T细胞、滑膜细胞、软骨细胞代谢及其细胞外基质的分解与合成平衡，维持软骨稳态。近期有多项研究表明，不同组织来源的间充质干细胞外泌体对骨关节炎均有明确的治疗作用，本文就MSCs来源的外泌体治疗KOA的具体机制进行综述，以期对干细胞治疗KOA提供理论依据。     

小鼠间充质干细胞诱导分化成脂肪细胞miRNA表达的变化

目的：探讨小鼠间充质干细胞（MSCs）定向诱导分化成脂肪细胞微小RNA（miRNA）表达的变化,为进一步研究miRNA调控MSCs向脂肪细胞分化的分子机制奠定基础。方法：采用全骨髓体外分离结合差速贴壁法纯化扩增C57BL／6小鼠MSCs,形态学观察细胞生长情况,并用免疫组化方法鉴定细胞表面抗原CD29、CIM4和CD34的表达。脂肪细胞分化诱导剂诱导MSCs分化为脂肪细胞,利用油红O染色,判断MSCs成脂分化情况。运用rrfiRNA芯片技术检测MSC8和脂肪细胞中差异表达的miRNA。结果：①倒置显微镜下观察,传5代后可获得均一性较高的MSCs;免疫组化显示90％以上的骨髓间质干细胞CD29、CD44阳性,CD34阴性。MSCs经脂肪诱导剂诱导后,胞内大量脂滴形成,油红O染色阳性;②基因微阵列分析表明,小鼠MSCs分化成脂肪细胞差异表达的miRNA共75个,其中20个表达上调、55个表达下调。结论：MSCs分化成脂肪细胞存在miRNA表达的变化,某些miRNA很可能具有重要的调控MSCs成脂分化的作用。     

Repair mechanisms of bone marrow mesenchymal stem cells in myocardial infarction

The prognosis of patients with myocardial infarction (MI) and resultant chronic heart failure remains extremely poor despite advances in optimal medical therapy and interventional procedures. Animal experiments and clinical trials using adult stem cell therapy following MI have shown a global improvement of myocardial function. Bone marrow-derived mesenchymal stem cells (MSCs) hold promise for cardiac repair following MI, due to their multilineage, self-renewal and proliferation potential. In addition, MSCs can be easily isolated, expanded in culture, and have immunoprivileged properties to the host tissue. Experimental studies and clinical trials have revealed that MSCs not only differentiate into cardiomyocytes and vascular cells, but also secrete amounts of growth factors and cytokines which may mediate endogenous regeneration via activation of resident cardiac stem cells and other stem cells, as well as induce neovascularization, anti-inflammation, anti-apoptosis, anti-remodelling and cardiac contractility in a paracrine manner. It has also been postulated that the anti-arrhythmic and cardiac nerve sprouting potential of MSCs may contribute to their beneficial effects in cardiac repair. Most molecular and cellular mechanisms involved in the MSC-based therapy after MI are still unclear at present. This article reviews the potential repair mechanisms of MSCs in the setting of MI.     

Cholinergic neuronal differentiation of bone marrow mesenchymal stem cells in rhesus monkeys

The purpose of the present study was to determine the best cholinergic neuronal differentiation method of rhesus monkey bone marrow mesenchymal stem cells(BMSCs).Four methods were used to induce differentiation,and the groups were assigned accordingly:basal inducing group(culture media,bFGF,and forskolin);SHH inducing group(SHH,inducing group);RA inducing group(RA,basal inducing group);and SHH+RA inducing group(SHH,RA,and basal inducing group).All groups displayed neuronal morphology and increased expressio...     

Bone marrow mesenchymal stem cells enhance autophagy and help protect cells under hypoxic and retinal detachment conditions

Our study aimed to evaluate the protective role and mechanisms of bone marrow mesenchymal stem cells (BMSCs) in hypoxic photoreceptors and experimental retinal detachment. The cellular morphology, viability, apoptosis and autophagy of hypoxic 661w cells and cells cocultured with BMSCs were analysed. In retinal detachment model, BMSCs were intraocularly transplanted, and then, the retinal morphology, outer nuclear layer (ONL) thickness and rhodopsin expression were studied as well as apoptosis and autophagy of the retinal cells. The hypoxia-induced apoptosis of 661w cells obviously increased together with autophagy levels increasing and peaking at 8 hours after hypoxia. Upon coculturing with BMSCs, hypoxic 661w cells had a better morphology and fewer apoptosis. After autophagy was inhibited, the apoptotic 661w cells under the hypoxia increased, and the cell viability was reduced, even in the presence of transplanted BMSCs. In retina-detached eyes transplanted with BMSCs, the retinal ONL thickness was closer to that of the normal retina. After transplantation, apoptosis decreased significantly and retinal autophagy was activated in the BMSC-treated retinas. Increased autophagy in the early stage could facilitate the survival of 661w cells under hypoxic stress. Coculturing with BMSCs protects 661w cells from hypoxic damage, possibly due to autophagy activation. In retinal detachment models, BMSC transplantation can significantly reduce photoreceptor cell death and preserve retinal structure. The capacity of BMSCs to reduce retinal cell apoptosis and to initiate autophagy shortly after transplantation may facilitate the survival of retinal cells in the low-oxygen and nutrition-restricted milieu after retinal detachment.     

Proteomic profiling of distinct clonal populations of bone marrow mesenchymal stem cells

Mesenchymal stem cells (MSCs) have attracted immense research interest in the field of regenerative medicine due to their ability to be cultured for successive passages and multi‐lineage differentiation. The molecular mechanisms governing MSC self‐renewal and differentiation remain largely unknown. The development of sophisticated techniques, in particular clinical proteomics, has enabled researchers in various fields to identify and characterize cell specific biomarkers for therapeutic purposes. This study seeks to understand the cellular and sub‐cellular processes responsible for the existence of stem cell populations in bone marrow samples by revealing the whole cell proteome of the clonal cultures of bone marrow‐derived MSCs (BMSCs). Protein profiling of the MSC clonal populations was conducted by Two‐Dimensional Liquid Chromatography/Matrix‐Assisted Laser Desorption/Ionisation (MALDI) Mass Spectrometry (MS). A total of 83 proteins were identified with high confidence of which 11 showed differential expression between subpopulations, which included cytoskeletal and structural proteins, calcium binding proteins, cytokinetic proteins, and members of the intermediate filament family. This study generated a proteome reference map of BMSCs from the clonal populations, which will be valuable to better understand the underlying mechanism of BMSC self‐renewal and differentiation. J. Cell. Biochem. 106: 776–786, 2009. © 2009 Wiley‐Liss, Inc.     

骨髓间充质干细胞向神经细胞分化的研究

无论是在体外实验、还是在体内实验,MSCs都可以向中枢神经系统(CNS)神经细胞分化,但争议颇多。因为功能性神经元不仅要具有典型神经元的形态、特异性标记,还要求具有可兴奋性、能和其他神经元形成突触联系、产生突触电位等,所以对于骨髓间充质干细胞是否能诱导出真正具有功能的神经元存在很大分歧。在此对MSCs向神经细胞诱导分化研究的现况、存在的问题及发展前景给以综述。     

重组杆状病毒转导恒河猴骨髓间充质干细胞

[目的]研究重组杆状病毒(Bac-CMV-EGFP)能否能有效转导恒河猴骨髓间充质干细胞(rhesus Bone marrow-derived Mesenchymal Stem Cells,rBMSCs),及杆状病毒转导后对细胞活力,增殖及分化能力的影响.[方法]体外原代培养rBMSCs,不同剂量的杆状病毒转导3代以后的细胞,并用流式细胞仪分别检测其转导效率.在较高的杆状病毒转导效率下,检测rBMSCs细胞活力,增殖及分化能力,并与正常对照组细胞进行比较.[结果]杆状病毒在感染指数(Multiplicity Of Infection,MOI)为300v.g/cell,孵育温度为25度,孵育时间为4h的转导条件下,对rBMSCs转导效率可达80%左右.进一步检测后发现,高效转导杆状病毒后的rBMSCs的细胞活力,增殖及分化能力与未转导病毒细胞组无明显变化.[结论]重组杆状病毒可安全有效地基因修饰rBMSCs,且不影响其生物特性,为今后的体内基因治疗灵长类动物模型试验奠定了基础.