大鼠骨髓间充质干细胞向成骨与成脂分化过程中相关基因的表达变化

目的探讨大鼠骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)向成骨与成脂分化过程中相关基因表达的变化。方法采用全贴壁法分离培养大鼠BMSCs,并观察其形态学特征的变化,MTT法检测其生长状况,并绘制生长曲线。分别采用成骨和成脂诱导剂对第4代BMSCs进行诱导分化,应用碱性磷酸酶试剂盒、茜素红和油红O染色液检测其ALP活性、成骨和成脂分化能力;RT-QPCR检测诱导0、7、14和21 d的成骨分化相关基因Runt相关转录因子2(Runx2)、骨钙素(osteocalcin,OCN)、碱性磷酸酶(ALP)及成脂分化相关基因过氧化物酶体增殖物激活受体γ(peroxidase proliferator activated receptor gamma,PPARγ)和脂肪酸结合蛋白(FABP4)的表达变化。结果全骨髓贴壁法能成功分离培养BMSCs,传代细胞生长增殖迅速,以长梭形细胞生长为主,细胞生长曲线呈S形。第4代BMSCs分别经成骨和成脂诱导剂诱导后,ALP、茜素红和油红O染色均呈阳性;诱导7、14和21 d后,Runx2、OCN、ALP、PPARγ和FABP4基因mRNA的表达量均显著高于0 d(P0.05);成骨分化过程中,Runx2和ALP在第7天时表达量最高,之后呈下降趋势,OCN的表达量呈稳定上升趋势;成脂分化过程中,PPARγ在第7天时表达量最高,FABP4始终高表达。结论 BMSCs具有易于体外分离培养、扩增和经诱导后具有多向分化潜能等特点,成骨和成脂分化相关基因的表达量随诱导时间延长而变化,呈明显的时序性表达差异,提示分别在成骨与成脂分化过程中起重要调控作用,为BMSCs在骨、细胞和基因等工程中的机制研究提供了实验依据。     

SF/COL/PLCL静电纺丝三维纳米纤维支架与人脐带血间充质干细胞的细胞相容性研究

目的研究SF/COL/PLCL静电纺丝三维纳米纤维支架与人脐带血(human umbilical cord blood,hUCB)间充质干细胞(mesenchymal stem cells,MSCs)的细胞相容性。方法分离、培养hUCBMSCs,并进行传代,取第3代hUCBMSCs,茜素红染色和Von Kossa染色检测其体外诱导成骨分化的能力;流式细胞术检测其表面相关抗原的表达。制备SF/COL/PLCL静电纺丝三维纳米纤维支架,扫描电镜观察其形貌表征,并检测其力学性能。将hUCBMSCs接种于静电纺丝三维纳米纤维支架上,观察细胞在支架上的生长及增殖情况。结果 hUCBMSCs具有成骨诱导分化能力,其表达CD44、CD29、CD90和CD105,不表达CD45和CD34。SF/COL/PLCL复合纳米纤维的纤维形貌良好,随着PLCL含量的增加,纤维的直径和力学性能均逐渐增加。hUCBMSCs能够在三维纳米纤维支架上很好地黏附,并相互连接向周围扩展,三维纳米纤维支架能很好地促进细胞黏附和增殖,与常规培养的细胞相比,差异有统计学意义(P0.05或P0.01),当SF/COL与PLCL的质量比为30∶70时,最有利于细胞的生长。结论 hUCBMSCs能够在SF/COL/PLCL静电纺丝纳米纤维支架上生长、增殖,这种支架材料具有良好的力学性能及细胞相容性,有望成为一种新型组织工程支架材料。     

脐带间充质干细胞长期体外培养的生物学特性及遗传稳定性

目的观察脐带间充质干细胞(umbilical cord mesenchymal stem cells,UC-MSCs)体外长期培养的生物学特性及遗传稳定性。方法从剖宫产足月健康新生儿脐带中分离培养UC-MSCs,并连续传代,显微镜下观察细胞形态。分别检测P3和P12代UC-MSCs的增殖能力、免疫表型、向成脂肪细胞和成骨细胞的分化诱导率、衰老情况、成纤维细胞集落形成单位(CFU-F)及染色体核型。结果 P3代UC-MSCs为形态相对均一的梭形贴壁细胞,呈平行排列生长或旋涡状生长;P12代UC-MSCs宽大扁平,贴壁性减退,漂浮细胞增多,胞浆内出现黑色颗粒和空泡;P3和P12代UCMSCs均表达CD73、CD90、CD105,不表达CD34、CD45、HLA-DR;P3较P12代UC-MSCs的细胞增殖能力及向成脂肪细胞分化诱导率均明显升高(P均0.05);向成骨细胞分化诱导率及细胞衰老率均明显降低(P均0.05);成纤维细胞集落数及染色体中期分裂相明显增多(P0.05)。结论长期体外培养的UC-MSCs生物学特性发生改变,遗传学特性稳定,但染色体中期分裂相减少。     

人脐带华通氏胶间充质干细胞的生物学特性及其向肌源性细胞分化的能力

目的探讨人脐带华通氏胶间充质干细胞(human umbilical cord Wharton′s Jelly mesenchymal stem cells,hUCMSCs)的生物学特性及其向肌源性细胞分化的能力。方法收集健康足月产胎儿脐带组织,采用酶消化法从华通氏胶中分离hUCMSCs,选取第3代对数生长期细胞,显微镜观察细胞形态,流式细胞术检测细胞免疫表型分子的表达,免疫荧光染色检测干细胞标记物及其体外向肌源性细胞的分化,荧光显微镜观察及流式细胞术检测携带绿色荧光蛋白(green fluorescent protein,GFP)的慢病毒转染hUCMSCs后GFP的表达。结果采用酶消化法获得可贴壁生长的大量hUCMSCs,其能在体外成功进行扩增培养。hUCMSCs可高表达CD29、CD44、CD73、CD90和CD105,而极低表达CD14、CD34、CD45和HLA-Ⅱ;能表达干细胞标记物Oct4和Sox2,且在体外特殊培养条件下表达骨骼肌干细胞标记物Pax7和Myo D;转染的hUCMSCs可稳定表达GFP,转染率高达50%~70%。结论人脐带华通氏胶组织存在间充质干细胞,且其具有向肌源性细胞分化的潜能。     

成骨生长肽对鼠骨髓间充质干细胞增殖及成骨分化的作用

目的探讨成骨生长肽(osteogenic growth peptide,OGP)对鼠骨髓间充质干细胞(mouse bone marrow mesenchymal stem cell,mBMSC)增殖及成骨分化的作用及其分子机制。方法采用乳鼠骨片法分离mBMSC,流式细胞术测定mBMSC表面特征性分子。以10-5 mol/L OGP10-14作用于mBMSC,以不含OGP10-14的成骨诱导培养基作为对照组,MTS法检测OGP10-14对mBMSC增殖的影响;茜素红染色评价OGP10-14对mBMSC成骨分化的作用;qPCR及Western blot法检测OGP10-14干预下mBMSC骨分化相关因子β-catenin、RUNX2、BSP和细胞周期相关因子cyclin B1、CDK2、c-myc mRNA及蛋白表达水平。结果原代分离培养的mBMSC高表达CD29和CD90,低表达CD45和CD11b/c,符合BMSC的表型特征。与对照组相比,OGP10-14组mBMSC培养24、48及72 h时均促进细胞增殖(P 0.05)。茜素红染色显示,对照组部分细胞呈聚集生长,集落状,随诱导时间延长,出现红色层状矿化结节,OGP10-14组mBMSC矿化结节较对照组呈增加趋势。与对照组比较,OGP10-14组β-catenin、RUNX2、BSP mRNA及蛋白水平均升高(P 0.05),cyclin B1、CDK2、c-myc mRNA及蛋白水平均明显升高(P 0.01)。结论 OGP10-14通过促进成骨分化和触发细胞周期cyclin B1/CDK2途径促进mBMSC增殖,进而促进骨形成。     

二次贴壁法高效制备人脐带间充质干细胞

目的采用二次贴壁法高效制备人脐带间充质干细胞(human umbilical cord derived mesenchymal stem cells,hUC-MSCs)。方法将传统组织块贴壁法弃掉的脐带组织块转移至新的培养瓶中进行二次贴壁,分离hUC-MSCs,并用无血清培养体系连续传代,镜下观察细胞形态;分别检测不同代次细胞的增殖能力、细胞周期、免疫表型、多向分化能力。结果二次贴壁法分离的hUC-MSCs在第4天即出现细胞克隆,第8天汇合度可达70%,经过二次贴壁法,1根20 cm的脐带组织共获得P3间充质干细胞(MSCs)总数为1×10~9个。二次贴壁分离的细胞增殖能力旺盛,与一次贴壁获得的干细胞同代次平均倍增时间差异无统计学意义(P0.05)。传统贴壁法与二次贴壁分离的细胞均表达超过98%的CD73、CD90、CD105和低于2%的CD34、CD45、CD14、CD79a、HLA-DR,且该细胞具有分化为成骨、成软骨和成脂能力。结论经无动物源培养体系体外扩增的二次贴壁分离方法可以获得大量具有MSCs生物学特性的hUC-MSCs,为其规模化临床应用奠定了基础。     

牛骨胶原蛋白肽促进人成骨细胞增殖

目的研究牛骨胶原蛋白肽对人成骨细胞增殖的影响。方法分离培养人成骨细胞,茜素红矿化染色鉴定人成骨细胞的成骨特性,利用MTT实验检测胶原蛋白肽对人成骨细胞的增殖效应。结果茜素红矿化染色结果表明,HBC具有成骨能力,胶原蛋白肽对HBC的增殖具有促进作用,0.3mg/ml胶原蛋白肽对细胞的增殖具有最佳效应。结论牛骨胶原蛋白肽促进人成骨细胞增殖,为骨质疏松的预防和治疗提供理论依据。     

4种来源的间充质干细胞的生物学特性比较

目的比较骨髓、骨骼肌、肋软骨膜及软骨来源的间充质干细胞(mesenchymal stem cells,MSCs)的生长、免疫表型及体外诱导分化能力的差异。方法分别获取新西兰大白兔的骨髓、骨骼肌、肋软骨膜细胞及软骨细胞,体外培养观察其生长形态、表型特征及其诱导成骨、成脂的分化能力。结果 4种来源的MSCs均从第2代开始转变为梭形,第3代逐渐出现漩涡状排列;骨髓、骨骼肌和软骨膜来源的细胞生长状态良好,可传10代以上,但软骨来源的细胞在第5代后,逐渐退变死亡。骨髓来源的原代细胞部分表达CD29、CD90、CD34,传代后不表达CD34,但CD29、CD90的表达逐代增强;骨骼肌、软骨膜及软骨来源的原代细胞均不表达CD29、CD90和CD34,从第2代开始均表达CD29、CD90,且不断增强;仅原代软骨细胞表达Ⅱ型胶原,至第2代基本不表达;无细胞表达Desmin。4种来源的第3代细胞经诱导均可分化为成骨细胞或成脂细胞。结论 4种来源的干细胞均具有MSCs的特点,但骨髓、骨骼肌、软骨膜来源的干细胞的生长明显强于软骨来源的干细胞。     

β-catenin对骨形态发生蛋白9诱导间充质干细胞成骨分化的影响

目的探讨经典Wnt信号通路关键节点β-catenin对骨形态发生蛋白9(bone morphogenetic protein 9,BMP9)诱导间充质干细胞(mesenchymal stem cells,MSCs)成骨分化的影响。方法用重组腺病毒介导BMP9在C3H10T1/2细胞中过表达,联用β-catenin重组腺病毒上调β-catenin的表达,并通过RNA干扰抑制β-catenin的表达。分析C3H10T1/2细胞碱性磷酸酶(alkaline phosphatase,ALP)活性的变化;RT-PCR检测细胞成骨分化相关基因骨桥蛋白(osteopontin,OPN)和骨钙蛋白(osteocalcin,OC)基因mRNA的转录水平;茜素红S染色检测细胞的钙盐沉积。结果 BMP9单独作用能诱导C3H10T1/2细胞向成骨方向分化,并增强细胞ALP活性;单独的β-catenin无成骨诱导作用,但可剂量依赖性地增强BMP9诱导的C3H10T1/2细胞的ALP活性,并促进BMP9诱导的细胞OPN和OC基因mRNA的转录水平及钙盐沉积;抑制β-catenin表达可显著降低BMP9诱导的C3H1OT1/2细胞的ALP活性(P0.05),下调OPN和OC基因mRNA的转录水平,并抑制钙盐沉积。结论经典Wnt信号通路可能通过β-catenin协同BMP9诱导C3H10T1/2细胞成骨分化,且BMP9诱导的成骨分化可能需要通过Wnt/β-catenin途径来实现。     

骨形态发生蛋白9-2双表达定向诱导多潜能干细胞C3H10的成骨分化

目的探讨骨形态发生蛋白(Bone morphogenetic protein,BMP)9-2双表达定向诱导多潜能干细胞C3H10向成骨细胞分化的情况。方法将C3H10细胞分为4组:BMP9-2、BMP2、BMP9和GFP组,将4种重组腺病毒分别感染C3H10细胞,通过碱性磷酸酶(Alkaline phosphatase,ALP)染色、定量测定及钙茜素红染色,观察BMP9-2双表达对C3H10细胞成骨分化的定向诱导作用。结果 BMP9-2双表达能诱导C3H10细胞ALP的表达,其染色活性高于BMP2组1.6倍,BMP9组2.5倍,GFP组4倍;其BMP9-2双表达定量表达A520值在病毒感染后5、7、9 d均高于BMP2、BMP9和GFP组;BMP9-2双表达能诱导C3H10细胞钙盐的沉积,感染14 d后,钙茜素红染色可见钙化结节,其染色活性高于BMP2组1.4倍,BMP9组1.3倍,GFP组5.2倍。结论 BMP9-2双表达能定向诱导C3H10细胞成骨分化,其成骨活性强于单一成骨诱导因子BMP2和BMP9。     

Concurrent Expression of Oct4 and Nanog Maintains Mesenchymal Stem-Like Property of Human Dental Pulp Cells

Human dental pulp stem cells (DPSCs), unique mesenchymal stem cells (MSCs) type, exhibit the characteristics of self-renewal and multi-lineage differentiation capacity. Oct4 and Nanog are pluripotent genes. The aim of this study was to determine the physiological functions of Oct4 and Nanog expression in DPSCs. Herein, we determined the critical role of an Oct4/Nanog axis modulating MSCs properties of DPSCs by lentiviral-mediated co-overexpression or co-knockdown of Oct4/Nanog in DPSCs. MSCs properties including osteogenic/chondrogenic/adipogenic induction differentiation was assayed for expression of osteogenic/chondrogenic/adipogenic markers by quantitative real-time RT-PCR analysis. Initially, we observed that the expression profile of Oct4 and Nanog in dental pulp cells, which exerted properties of MSCs, was significantly up-regulated compared to that of STRO-1⁻CD146⁻ dental pulp cells. Down-regulation of Oct4 and Nanog co-expression significantly reduced the cell proliferation, osteogenic differentiation capability, STRO-1, CD146, and Alkaline phosphatase (ALP) activity of DPSCs. In contrast, co-overexpression of Oct4 and Nanog enhanced the expression level of STRO-1 and CD146, proliferation rate and osteogenic/chondrogenic/adipogenic induction differentiation capability, and expression of osteogenic/chondrogenic/adipogenic induction differentiation markers. Our results suggest that Oct4-Nanog signaling is a regulatory switch to maintain properties in DPSCs.     

Silicon–Gold Nanoparticles Affect Wharton’s Jelly Phenotype and Secretome during Tri-Lineage Differentiation

Multiple studies have demonstrated that various nanoparticles (NPs) stimulate osteogenic differentiation of mesenchymal stem cells (MSCs) and inhibit adipogenic ones. The mechanisms of these effects are not determined. The aim of this paper was to estimate Wharton’s Jelly MSCs phenotype and humoral factor production during tri-lineage differentiation per se and in the presence of silicon–gold NPs. Silicon (SiNPs), gold (AuNPs), and 10% Au-doped Si nanoparticles (SiAuNPs) were synthesized by laser ablation, characterized, and studied in MSC cultures before and during differentiation. Humoral factor production (n = 41) was analyzed by Luminex technology. NPs were nontoxic, did not induce ROS production, and stimulated G-CSF, GM-CSF, VEGF, CXCL1 (GRO) production in four day MSC cultures. During MSC differentiation, all NPs stimulated CD13 and CD90 expression in osteogenic cultures. MSC differentiation resulted in a decrease in multiple humoral factor production to day 14 of incubation. NPs did not significantly affect the production in chondrogenic cultures and stimulated it in both osteogenic and adipogenic ones. The major difference in the protein production between osteogenic and adipogenic MSC cultures in the presence of NPs was VEGF level, which was unaffected in osteogenic cells and 4–9 times increased in adipogenic ones. The effects of NPs decreased in a row AuNPs > SiAuNPs > SiNPs. Taken collectively, high expression of CD13 and CD90 by MSCs and critical level of VEGF production can, at least, partially explain the stimulatory effect of NPs on MSC osteogenic differentiation.     

Cartilage Oligomeric Matrix Protein Gene Multilayers Inhibit Osteogenic Differentiation and Promote Chondrogenic Differentiation of Mesenchymal Stem Cells

There are still many challenges to acquire the optimal integration of biomedical materials with the surrounding tissues. Gene coatings on the surface of biomaterials may offer an effective approach to solve the problem. In order to investigate the gene multilayers mediated differentiation of mesenchymal stem cells (MSCs), gene functionalized films of hyaluronic acid (HA) and lipid-DNA complex (LDc) encoding cartilage oligomeric matrix protein (COMP) were constructed in this study via the layer-by-layer self-assembly technique. Characterizations of the HA/DNA multilayered films indicated the successful build-up process. Cells could be directly transfected by gene films and a higher expression could be obtained with the increasing bilayer number. The multilayered films were stable for a long period and DNA could be easily released in an enzymatic condition. Real-time polymerase chain reaction (RT-PCR) assay presented significantly higher (p < 0.01) COMP expression of MSCs cultured with HA/COMP multilayered films. Compared with control groups, the osteogenic gene expression levels of MSCs with HA/COMP multilayered films were down-regulated while the chondrogenic gene expression levels were up-regulated. Similarly, the alkaline phosphatase (ALP) staining and Alizarin red S staining of MSCs with HA/COMP films were weakened while the alcian blue staining was enhanced. These results demonstrated that HA/COMP multilayered films could inhibit osteogenic differentiation and promote chondrogenic differentiation of MSCs, which might provide new insight for physiological ligament-bone healing.     

Biological Characteristics and Osteogenic Differentiation of Ovine Bone Marrow Derived Mesenchymal Stem Cells Stimulated with FGF-2 and BMP-2

Cell-based therapies using mesenchymal stem cells (MSCs) are a promising tool in bone tissue engineering. Bone regeneration with MSCs involves a series of molecular processes leading to the activation of the osteoinductive cascade supported by bioactive factors, including fibroblast growth factor-2 (FGF-2) and bone morphogenetic protein-2 (BMP-2). In this study, we examined the biological characteristics and osteogenic differentiation potential of sheep bone marrow MSCs (BM-MSCs) treated with 20 ng/mL of FGF-2 and 100 ng/mL BMP-2 in vitro. The biological properties of osteogenic-induced BM-MSCs were investigated by assessing their morphology, proliferation, phenotype, and cytokine secretory profile. The osteogenic differentiation was characterized by Alizarin Red S staining, immunofluorescent staining of osteocalcin and collagen type I, and expression levels of genetic markers of osteogenesis. The results demonstrated that BM-MSCs treated with FGF-2 and BMP-2 maintained their primary MSC properties and improved their osteogenic differentiation capacity, as confirmed by increased expression of osteocalcin and collagen type I and upregulation of osteogenic-related gene markers BMP-2, Runx2, osterix, collagen type I, osteocalcin, and osteopontin. Furthermore, sheep BM-MSCs produced a variety of bioactive factors involved in osteogenesis, and supplementation of the culture medium with FGF-2 and BMP-2 affected the secretome profile of the cells. The results suggest that sheep osteogenic-induced BM-MSCs may be used as a cellular therapy to study bone repair in the preclinical large animal model.     

Isolation and Multiple Differentiation Potential Assessment of Human Gingival Mesenchymal Stem Cells

The aim of this study was to isolate human mesenchymal stem cells (MSCs) from the gingiva (GMSCs) and confirm their multiple differentiation potentials, including the odontogenic lineage. GMSCs, periodontal ligament stem cells (PDLSCs) and dermal stem cells (DSCs) cultures were analyzed for cell shape, cell cycle, colony-forming unit-fibroblast (CFU-F) and stem cell markers. Cells were then induced for osteogenic and adipogenic differentiation and analyzed for differentiation markers (alkaline phosphatase (ALP) activity, mineralization nodule formation and Runx2, ALP, osteocalcin (OCN) and collagen I expressions for the osteogenic differentiation, and lipid vacuole formation and PPARγ-2 expression for the adipogenic differentiation). Besides, the odontogenic differentiation potential of GMSCs induced with embryonic tooth germ cell-conditioned medium (ETGC-CM) was observed. GMSCs, PDLSCs and DSCs were all stromal origin. PDLSCs showed much higher osteogenic differentiation ability but lower adipogenic differentiation potential than DSCs. GMSCs showed the medial osteogenic and adipogenic differentiation potentials between those of PDLSCs and DSCs. GMSCs were capable of expressing the odontogenic genes after ETGC-CM induction. This study provides evidence that GMSCs can be used in tissue engineering/regeneration protocols as an approachable stem cell source.     

Modulation of Mesenchymal Stem Cells for Enhanced Therapeutic Utility in Ischemic Vascular Diseases

Mesenchymal stem cells are multipotent stem cells isolated from various tissue sources, including but not limited to bone marrow, adipose, umbilical cord, and Wharton Jelly. Although cell-mediated mechanisms have been reported, the therapeutic effect of MSCs is now recognized to be primarily mediated via paracrine effects through the secretion of bioactive molecules, known as the “secretome”. The regenerative benefit of the secretome has been attributed to trophic factors and cytokines that play neuroprotective, anti-angiogenic/pro-angiogenic, anti-inflammatory, and immune-modulatory roles. The advancement of autologous MSCs therapy can be hindered when introduced back into a hostile/disease environment. Barriers include impaired endogenous MSCs function, limited post-transplantation cell viability, and altered immune-modulatory efficiency. Although secretome-based therapeutics have gained popularity, many translational hurdles, including the heterogeneity of MSCs, limited proliferation potential, and the complex nature of the secretome, have impeded the progress. This review will discuss the experimental and clinical impact of restoring the functional capabilities of MSCs prior to transplantation and the progress in secretome therapies involving extracellular vesicles. Modulation and utilization of MSCs–secretome are most likely to serve as an effective strategy for promoting their ultimate success as therapeutic modulators.     

Characterization of Osteogenesis and Chondrogenesis of Human Decellularized Allogeneic Bone with Mesenchymal Stem Cells Derived from Bone Marrow,Adipose Tissue,and Wharton’s Jelly

Allogeneic bone grafts are a promising material for bone implantation due to reduced operative trauma, reduced blood loss, and no donor-site morbidity. Although human decellularized allogeneic bone (hDCB) can be used to fill bone defects, the research of revitalizing hDCB blocks with human mesenchymal stem cells (hMSCs) for osteochondral regeneration is missing. The hMSCs derived from bone marrow, adipose tissue, and Wharton’s jelly (BMMSCs, ADMSCs, and UMSCs, respectively) are potential candidates for bone regeneration. This study characterized the potential of hDCB as a scaffold for osteogenesis and chondrogenesis of BMMSCs, ADMSCs, and UMSCs. The pore sizes and mechanical strength of hDCB were characterized. Cell survival and adhesion of hMSCs were investigated using MTT assay and F-actin staining. Alizarin Red S and Safranin O staining were conducted to demonstrate calcium deposition and proteoglycan production of hMSCs after osteogenic and chondrogenic differentiation, respectively. A RT-qPCR was performed to analyze the expression levels of osteogenic and chondrogenic markers in hMSCs. Results indicated that BMMSCs and ADMSCs exhibited higher osteogenic potential than UMSCs. Furthermore, ADMSCs and UMSCs had higher chondrogenic potential than BMMSCs. This study demonstrated that chondrogenic ADMSCs- or UMSCs-seeded hDCB might be potential osteochondral constructs for osteochondral regeneration.     

Exosomes Derived from Human Umbilical Cord Mesenchymal Stem Cells Accelerate Diabetic Wound Healing via Promoting M2 Macrophage Polarization,Angiogenesis, and Collagen Deposition

Some scholars have suggested that the clinical application of exosomes derived from human umbilical cord mesenchymal stem cells (hucMSCs-exo) might represent a novel strategy to improve diabetic wound healing. However, the mechanisms underlying the effects of hucMSCs-exo on wound healing remain poorly understood. This study aimed to identify the mechanism of hucMSCs-exo in treating diabetic wounds. HucMSCs-exo were isolated from human umbilical cord mesenchymal stem cells (hucMSCs) and subcutaneously injected into full-thickness wounds in diabetic rats. Wound healing closure rates and histological analysis were performed. The levels of tumor necrosis factor-α (TNF-α), macrophage mannose receptor (MMR/CD206), platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31), and vascular endothelial growth factor (VEGF) were detected by immunohistochemistry. The degree of collagen deposition was examined using Masson’s trichrome staining. Gross evaluation of wound healing was carried out from day 0 to 14 post-surgery, and the wound site was harvested for histology on days 3, 7, and 14 post-wounding. HucMSCs-exo transplantation increased diabetic wound healing. In vitro, hucMSCs-exo promoted the proliferation of human umbilical vein endothelial cells (HUVECs) and NIH-3T3 cells. In vivo, hucMSCs-exo reduced wound area and inflammatory infiltration and increased collagen fibers. In addition, wound tissues in the hucMSCs-exo group had higher CD206, CD31, and VEGF expressions and lower TNF-α levels than those in the control group on day 14. Our results demonstrated that hucMSCs-exo facilitated diabetic wound repair by inducing anti-inflammatory macrophages and promoting angiogenesis and collagen deposition.