外泌体在心房颤动中的作用研究进展

心房颤动是临床上最常见的快速性心律失常之一,常引起脑卒中、冠心病、心力衰竭、肢体动脉栓塞等严重并发症,是导致患者不良预后的重要因素.外泌体是细胞释放的30～150 nm大小的双层脂质囊泡,携带蛋白质、核酸和脂质等生物活性物质;其作为信息传递的媒介,在细胞间通讯中起着关键作用.近年研究发现外泌体广泛参与心血管疾病的病理生...     

外泌体微RNA在缺血性卒中神经损伤及保护中的作用

外泌体是细胞经过一系列调控形成并可分泌到细胞外的膜性囊泡,其可以携带核酸、脂质和蛋白质进行细胞间的物质传递和信息交流。研究显示,外泌体微RNA(miRNAs)可参与脑正常的生理过程,也参与损伤修复等病理过程。缺血性卒中是世界范围内的严重致残、致死性疾病,卒中神经损伤或神经保护进程中涉及到众多分子变化,而外泌体中的miRNAs可能参与这些变化,成为缺血性卒中神经损伤或保护的生物标志物和潜在的治疗靶点。本研究通过对外泌体miRNAs在缺血性卒中神经损伤及保护中作用的综述,为缺血性卒中的诊断和潜在治疗提供新的方向。     

外泌体检测在骨肿瘤诊疗中的研究进展

［摘要］　体液检查已成为肿瘤研究领域的重要方向。来源于母体肿瘤细胞的外泌体含有mRNA、miRNA及其他基因组蛋白。这些基因组蛋白具备母体肿瘤的特异性,在肿瘤的发现、诊断以及治疗方面起到了重要作用。该文对外泌体检测在骨肿瘤诊疗中的研究进展作一综述。     

外泌体miRNA在肿瘤进展中的作用及其可能机制

外泌体是一种生物纳米小囊泡、直径约30~100 nm,机体中几乎所有类型的细胞均可以合成、分泌、释放。最新研究发现,外泌体中包含多种功能蛋白质、mRNA和microRNAs （miRNAs）等,在细胞间进行物质传递和信息交流过程中起着非常重要的作用。而肿瘤细胞分泌的相关外泌体miRNA,对肿瘤的发生、发展、侵袭转移等生...     

不同细胞来源外泌体参与心血管疾病发生的研究进展

外泌体是一种细胞外囊泡,可通过内溶酶体途径被细胞释放,作为信息载体参与细胞间通讯。不同细胞可分泌不同外泌体,后者携带的物质包括微小RNA、蛋白质、脂质等。有研究发现不同来源外泌体所携带的内容物也不尽相同,在细胞间通讯中起到重要作用。该文介绍外泌体在心血管各细胞间的通讯作用,为临床进一步探索相关靶向治疗提供新思路。     

外泌体来源微小RNA在心血管疾病中作用研究进展

在不同的病理生理状态下,细胞可分泌包含有特定内含物的外泌体至细胞外环境中。其中,来源于外泌体的微小RNA(miRNA)能够参与细胞间的物质传递和信号转导。近年来,人们逐渐认识到外泌体及其相关的miRNA在心血管疾病发病过程中的重要作用。本文介绍了外泌体的基本特征及外泌体来源的miRNA的生物学特性,讨论了外泌体来源的miRNA在不同心血管疾病中的表达情况。     

不同干细胞来源的外泌体在缺血性心脏病中的促血管新生作用

缺血性心脏病是指各种原因造成心肌供血量不足,导致氧气和营养物质供应不足,引起各种心脏功能障碍.促血管新生是治疗缺血性心脏病的一个关键因素.越来越多的研究表明,干细胞来源的外泌体作为一种细胞间相互作用的媒介,为缺血性心脏病的治疗提供了新的可能.现对各种干细胞来源的外泌体在治疗缺血性心脏病中促血管新生作用及机制做一综述.     

外泌体在呼吸系统疾病诊治中的作用

外泌体是细胞经过“内吞-融合-外排”等一系列调控过程而形成的细胞外纳米级小囊泡,具有广泛的生物功能,例如细胞间交流、信号转导、运输遗传物质和调节免疫反应等作用,多种类型的细胞可分泌外泌体,在血液、尿液以及 BALF 中均能分离到外泌体。现对其基本特点、生理功能及其在呼吸系统疾病诊治中的作用进行综述。     

Novel method for extracting exosomes of hepatocellular carcinoma cells

AIM:To develop a novel method for the rapid and efficient extraction of exosomes secreted by tumor cells.METHODS:Unlike the traditional extraction method,the supernatants of cell cultures were concentrated,and the exosomes were isolated promptly and effectively using a novel nanomaterial called ExoQuick.Coomassie brilliant blue staining was used for protein quantification,and the morphology of the exosomes extracted by both methods was visualized by transmis-sion electron microscopy.Exosome marker proteins were detected by Western blot analysis.Two potential hepatoma-associated proteins,tissue transglutaminase2(TGM2)and annexin A2,were analyzed.RESULTS:The exosomes separated by the new extraction assay based on the nanomaterial were discshaped,intact vesicles with lipid bilayer membranes.They were approximately 30-100 nm in diameter,which is similar to the diameter of exosomes isolated by the traditional method.The protein concentration of exosomes extracted by the new method was approximately780μg/108 cells,and therefore,it was 19 times higher than that of exosomes extracted in the traditional manner.There were differences between the total proteins of Huh-7 cells and the exosomal proteins.Typical exosome proteins,such as the transmembrane protein CD63 and heat shock protein 70,were confirmed.Two potential hepatoma-associated proteins were also identified.TGM2 was first found to exist in the exosomes of human liver cancer cells,but annexin A2 was not secreted into exosomes.CONCLUSION:The new extraction method based on the nanomaterial is quick and efficient.The cancerassociated protein TGM2 can be secreted through an exosome-mediated non-classical secretion pathway,and it may be a valuable tumor marker.     

Exosomes对L1210肿瘤细胞攻击的免疫保护作用研究

目的：观察L1210小鼠白血病细胞分泌的exosomes的抗肿瘤作用。方法：采用离心超滤和蔗糖密度梯度离心法分离L1210细胞释放的exosomes。固相免疫电镜法制备exosomes的H-2D，ICAM-1电镜标本，免疫印迹观察exosomes中HSP70的表达情况。exosomes免疫DBA／2小鼠，检测特异性细胞毒性T淋巴细胞（CTL）活性；免疫后的小鼠以L1210肿瘤细胞攻击，观察免疫保护效果。结果：L1210细胞分泌的exosomes为直径介于50～100nm的膜性微囊，圆形或椭圆形。抗H-2D，ICAM-1抗体-胶体金免疫电镜标记，囊外膜可见点状、颗粒状电子致密物沉积。通过免疫印迹证明其表达HSP70。Exosomes免疫小鼠，可诱导产生针对L1210细胞的CTL反应；L1210的exosomes（2．5及5扯g）免疫小鼠后，接种L1210肿瘤细胞，有明显的抵抗肿瘤生长作用。结论：L1210分泌的exosomes在同基因小鼠模型中可产生较强的保护性免疫力，exosomes疫苗可作为白血病等恶性肿瘤免疫治疗的候选疫苗。     

络瘀通胶囊对大鼠脑缺血-再灌注损伤的作用

目的观察并探讨络瘀通胶囊对大鼠脑缺血-再灌注后神经功能的影响及其保护机制。方法采用改良Longa法制备大鼠大脑中动脉阻塞(MCAO)模型,缺血1.5 h后进行再灌注。选取10只大鼠作为假手术组,将40只造模成功的雄性SD大鼠按照随机数字表法分为4组,每组10只:模型组、络瘀通中剂量组(LYTM组)、络瘀通高剂量组(LYTH组)及胞磷胆碱钠组(CS组)。分别于造模后3 d及7 d采用12分评分及前肢踩空实验评价大鼠神经功能,应用蛋白免疫印迹法(Western blot)检测造模3 d后大鼠缺血侧及假手术组同侧脑组织中脑源性神经营养因子(BDNF)、碱性成纤维生长因子(b-FGF)及磷酸化蛋白激酶/蛋白激酶(p-AKT/AKT)的表达,及造模后7 d同侧脑组织中Caspase-12的表达并进行组间比较。结果 (1)神经功能评分:造模后3 d各组12分评分及前肢踩空实验评分差异均无统计学意义(均P0.05);造模后7 d,LYTM组、LYTH组、CS组较模型组均明显改善(均P0.05)。(2)Western blot结果显示:1模型组BDNF及b-FGF表达明显少于假手术组(均P0.05);与模型组比较,LYTM组、LYTH组、CS组均可上调BDNF和b-FGF表达,以LYTH组作用最明显(P0.01)。2与假手术组比较,模型组p-AKT/AKT表达明显减少(P0.05);与模型组比较,LYTM组、LYTH组、CS组p-AKT/AKT表达增加,以LYTH组和CS组明显,差异均有统计学意义(均P0.05)。3在Caspase-12的表达中,模型组裂解后Caspase-12表达较假手术组明显升高,差异有统计学意义(P0.05)。与模型组比较,LYTM组、LYTH组Caspase-12前体(pro Caspase-12)和裂解后Caspase-12表达有减少趋势,但差异无统计学意义(均P0.05);CS组Caspase-12前体和裂解后Caspase-12表达水平明显低于模型组(P0.05)。结论络瘀通胶囊可通过促进神经元存活及再生对大鼠脑缺血-再灌注性损伤起到保护作用,且该保护作用也可能与抑制神经细胞凋亡有关。     

Effect of 5-Aza-2’-deoxycytidine on immune-associated proteins in exosomes from hepatoma

AIM: To study the effect of 5-Aza-2’-deoxycytidine (5-Aza-CdR) on heat shock protein 70 (HSP70), human leucocyte antigen-Ⅰ (HLA-Ⅰ) and NY-ESO-1 proteins in exosomes produced by hepatoma cells, HepG2 and Hep3B. METHODS: Exosomes derived from HepG2 and Hep3B cells treated with or without 5-aza-CdR were isolated and purified by ultrafiltration centrifugation and sucrose gradient ultracentrifugation. The number of exosomes was counted under electron microscope. Concentration of proteins in exosomes was measured...     

缺血再灌注损伤对SD乳鼠器官型脑片神经再生的影响

目的探讨缺血再灌注损伤对SD乳鼠器官型脑片中神经再生的影响。方法制备P3SD乳鼠的全脑器官型脑片,随机分为缺血再灌注组和正常对照组,观察脑片生长情况,培养3天后,两组再分别分为2个亚组,分别给予药物和空白干预,依次列为Ⅰ组、Ⅱ组、Ⅲ组和Ⅳ组,通过倒置显微镜及免疫荧光染色观察各组脑片在1、3、7天的改变。结果缺血再灌注组室下区、海马齿状回可见巢蛋白阳性新生细胞,而正常对照组未见新生细胞;药物干预后,两组均出现大量新生细胞,但正常对照组单位区域新生细胞数量多于缺血再灌注组(P<0.01);Ⅲ组较Ⅰ、Ⅱ组明显增多(P<0.01),随着培养时间延长,两组新生细胞均向外迁移,上述区域新生细胞密度逐渐减少。结论缺血再灌注损伤可以促进SD乳鼠器官型脑片神经再生,但同时也损伤了神经再生的潜能。     

Effect of platelet-rich plasma on reconstruction with nerve autografts

Despite advances in understanding of peripheral nerve injuries and regeneration and advances in surgical techniques, successful outcomes cannot be guaranteed after reconstructive surgery. Platelet-rich plasma (PRP) has been reported to have positive effects on nerve regeneration, as well as on tissue healing. The present study was designed to evaluate the effect of PRP on nerve-grafted defects. Sprague–Dawley rats were divided into four surgery groups (n = 7 in each). A 1-cm long nerve defect was created in the upper thigh and then reconstructed using a nerve autograft in all groups. The wet muscle weights, electromyographic findings, and histomorphologic changes were evaluated 10 weeks later. As shown by both the electromyographic (p < 0.001) and histomorphologic findings (p < 0.001), PRP had more positive effects on nerve gap reconstruction in Group 3 then Group 4 as compared to the control groups. The present study is novel in that it evaluated the regeneration effect of PRP on a large nerve defect reconstructed with a nerve graft rather than primary repair. The results are encouraging for further experimental studies on the role of PRP in nerve healing.     

斯氏狸殖吸虫体壁神经细胞与神经纤维的观察

目的　探讨斯氏狸殖吸虫的体壁神经细胞和神经纤维的分布特点和相互间关系。方法　采用乙酰胆碱酯酶定位技术对斯氏狸殖吸虫的神经细胞和神经纤维进行显示。结果　斯氏狸殖吸虫前部体壁内神经纤维密集 ,以纵行神经纤维为主 ,虫体中部以相互交叉的斜行神经纤维为主。斯氏狸殖吸虫有两类神经细胞 ,即双极和多极神经细胞 ;虫体前部的纵行神经纤维上以多极神经细胞分布较多 ,中部较少 ,后部最少。双级神经细胞分布于神经节内、神经干内过神经干旁。在虫体的横截面上 ,神经细胞位于神经纤维下。结论　斯氏狸殖吸虫的前部体壁神经纤维密集 ,多极神经细胞较多 ,可能与虫体前部肌活动能力强有密切关系。     

Impaired nerve fiber regeneration in axotomized peripheral nerves in streptozotocin‐diabetic rats

Aim/Introduction

Impaired nerve fiber regeneration is a salient feature of diabetic neuropathy. Its pathogenesis is still unclear. We attempted to characterize the structure of regenerated myelinated fibers after transection in streptozotocin‐diabetic rats.

Materials and Methods

Streptozotocin‐diabetic rats underwent transection of the sciatic nerve. Two and 4 weeks post‐axotomy, regenerated myelinated fibers of the cut end and fibers at its proximal site were morphometrically examined. Non‐diabetic control rats with axotomy were also examined for comparison.

Results

At 4 weeks post‐axotomy, diabetic rats showed an increased myelinated fiber density and total fiber number with a trend toward reduced fiber size at the cut end compared with those in control rats. The average number of myelin lamellae relative to axonal size in regenerated fibers at the cut end was significantly reduced in diabetic rats compared with that in control rats. The proximal site showed a reduced size of fibers and axons in both diabetic and control rats to a similar extent compared with those in a non‐axotomized state. At 2 weeks post‐axotomy, these findings were less apparent.

Conclusions

The nerves of diabetic rats when axotomized undergo impaired regeneration characterized by increased fiber density with hypomyelination.     

间充质干细胞来源的外泌体在心血管疾病中的研究现状

心血管疾病严重威胁人类健康,仍是导致人类死亡的主要原因,而间充质干细胞(MSC)释放的外泌体作用于心脏和血管,可以发挥抗凋亡、抗炎、抗纤维化以及促进内皮细胞和血管生成等作用,被认为是MSC移植治疗关键的作用机制。文章总结近5年国内外相关研究,综述了MSC来源的外泌体在治疗心血管疾病中的作用机制,并讨论了外泌体作为未来心血管疾病治疗的新途径。