在海藻酸钠凝胶上诱导骨髓间充质干细胞分化为成骨细胞

通过在海藻酸钠凝胶上诱导bMSCs向成骨细胞分化,探讨其对骨髓间充质干细胞（bone mesenchymal stem cells, bMSCs）的生物学效应。采用MTT、甲苯胺蓝染色、von Kossa染色和RT-PCR分别检测细胞的增殖、生长形态、诱导后细胞的钙化结节和成骨相关基因的表达。实验组bMSCs生长状况良好、细胞增殖迅速,与对照组的增殖无差异;bMSCs成集落样生长明显,集落中央细胞重叠生长形成钙化结节;培养至12d,实验组和对照组的成骨相关基因,包括碱性磷酸酶、I型胶原和骨钙素,均为阳性表达,但实验组的表达量高于对照组。海藻酸钠凝胶能够促进bMSCs向成骨细胞的分化,是良好的骨组织工程支架材料。     

Nanotopography Alters Nuclear Protein Expression,Proliferation and Differentiation of Human Mesenchymal Stem/Stromal Cells

Mesenchymal stem/stromal cells respond to physical cues present in their microenvironment such as substrate elasticity, geometry, or topography with respect to morphology, proliferation, and differentiation. Although studies have demonstrated the role of focal adhesions in topography-mediated changes of gene expression, information linking substrate topography to the nucleus remains scarce. Here we show by two-dimensional gel electrophoresis and western blotting that A-type lamins and retinoblastoma protein are downregulated in mesenchymal stem/stromal cells cultured on 350 nm gratings compared to planar substrates; these changes lead to a decrease in proliferation and changes in differentiation potential.     

间充质干细胞通过分解代谢糖酵解促进肺癌细胞生长（英文）

存在于骨髓中的间充质干细胞(bone marrow mesenchymal stem cells,BMSCs,也称为间充质基质细胞)可以被募集到肿瘤部位并构成肿瘤微环境。细胞代谢在癌症进展中起重要作用。在癌症微环境中间充质细胞和肿瘤细胞发生代谢方式的转变。然而,尚不清楚肿瘤细胞和BMSCs细胞的相互作用如何影响细胞代谢和肿瘤进展。在本研究中,通过将BMSCs和小鼠肺癌细胞LLC细胞共同注射到C57BL/6小鼠,构建了皮下瘤模型;随后在原位瘤分离BMSCs和LLC细胞,进行RNA测序,以获得肿瘤微环境下BMSCs和LLC细胞的转录组。结果显示BMSCs中上调的基因富集于代谢途径。进一步根据差异表达的分子构建相互作用网路,发现BMSCs网络中的核心预测途径是代谢途径、MAPK信号通路和HIF-1信号通路。然而,在肿瘤微环境中LLC细胞的代谢途径受到抑制。体内动物实验证实抑制糖酵解可以减少荷瘤小鼠肿瘤的生长。以上结果提示,BMSCs增加了糖酵解,通过反式Warburg效应促进癌细胞的生长,在肿瘤微环境下BMSCs的代谢重编程影响肿瘤细胞的转归。     

从人胚胎干细胞畸胎瘤中有效获取间充质干细胞和神经前体细胞

通过人胚胎干细胞(human embryonic stem cells,hESC)体外分化方法和畸胎瘤形成可以分化获得多种成体细胞．但目前尚不清楚是否可以从hESCs畸胎瘤中分离某些特异性细胞．通过体外筛选方法,有效地从hESCs畸胎瘤中分离出神经前体细胞(neural progenitor cells,NPCs)和间充质干细胞(mesenchymal stem cells,MSCs)．这种hESCs畸胎瘤来源的NPCs和MSCs与体内神经前体细胞和间充质干细胞有着相似的分子标记和特性,并具有进一步的分化潜能——分别可以诱导成为神经元、神经胶质细胞、脂肪细胞和骨骼细胞等．根据人胚胎干细胞畸胎瘤中含有不同分化阶段的外胚层、中胚层和内胚层的组织或细胞,认为人胚胎干细胞畸胎瘤可以作为另一个细胞来源以获取多种(包括人胚胎干细胞体外分化难以得到的)各种前体/干细胞和终末分化细胞．     

牙源性间充质干细胞对成骨前体细胞成骨分化的影响

目的:探讨牙源性间充质干细胞对成骨前体细胞成骨分化的影响.方法:将小鼠成骨前体细胞MC3T3-El分为两组,观察组为牙源性间充质干细胞与MC3T3-E1细胞共培养,对照组为单一MC3T3-E1细胞培养.采用CCK-8法检测细胞增殖水平,采用酶联免疫法检测碱性磷酸酶(Alkaline phosphatase,ALP)活性...     

体外诱导大鼠脂肪间充质干细胞向肝细胞方向分化的研究

目的:探讨大鼠脂肪间充质干细胞(ADMSCs)是否可以在体外被诱导向肝细胞方向分化。方法:从大鼠脂肪组织中分离出干细胞,行体外扩增、传代;用免疫荧光染色法检测其表面标志,用成纤维细胞生长因子(FGF-4)和肝细胞生长因子(HGF)诱导其向肝细胞分化;倒置显微镜观察细胞形态变化,诱导后14天和21天分别用免疫荧光检测法检测肝细胞标志物白蛋白的表达,每次换液时留取培养上清用尿素氮测试盒检测尿素氮含量。结果:免疫荧光检测显示从脂肪组织所获取的细胞表面标志CD29阳性,而CD31和CD145均为阴性;诱导14天后可逐渐观察到肝细胞样形态改变;免疫荧光检测到白蛋白表达;尿素氮检测显示诱导组尿素氮含量随时间延长而逐渐升高。结论:从大鼠脂肪组织中获取的脂肪间充质干细胞能在体外被诱导分化成形态、表型及功能与肝细胞相似的细胞。     

Physical Regulation of Human Mesenchymal Stem Cells through Altered Calcium Dynamics

This article has no abstract.     

DJ‐1 Regulates Differentiation of Human Mesenchymal Stem Cells into Smooth Muscle‐like Cells in Response to Sphingosylphosphorylcholine

Although multiple factors contribute to the differentiation of human mesenchymal stem cells (hMSCs) into various types of cells, the differentiation of hMSCs into smooth muscle cells (SMCs), one of central events in vascular remodeling, remains to be clarified. ROS participate in the differentiation of hMSCs into several cell types and were regulated by redox‐sensitive molecules including a multifunctional protein DJ‐1. Here, we investigated the correlation between altered proteins, especially those related to ROS, and SMC differentiation in sphingosylphosphorylcholine (SPC)‐stimulated hMSCs. Treatment with SPC resulted in an increased expression of SMC markers, namely α‐smooth muscle actin (SMA) and calponin, and an increased production of ROS in hMSCs. A proteomic analysis of SPC‐stimulated hMSCs revealed a distinctive alteration of the ratio between the oxidized and reduced forms of DJ‐1 in hMSCs in response to SPC. The increased abundance of oxidized DJ‐1 in SPC‐stimulated hMSCs was validated by immunoblot analysis. The SPC‐induced increase in the expression of α‐SMA was stronger in DJ‐1‐knockdown hMSCs than in control cells. Moreover, the expression of α‐SMA, and the calponin and generation of ROS in response to SPC were weaker in normal hMSCs than in DJ‐1‐overexpressing hMSCs. Exogenous H₂O₂ mimicked the responses induced by SPC treatment. These results indicate that the ROS‐related DJ‐1 pathway regulates the differentiation of hMSCs into SMCs in response to SPC.     

bFGF Promotes the Proliferation of Rat Peripheral Blood Mesenchymal Stem Cells Through β-Catenin Signaling

bFGF (basic fibroblast growth factor, bFGF) could promote the proliferation of bone marrow and cord blood mesenchymal stem cells. However, the effect of bFGF on the proliferation of peripheral blood mesenchymal stem cells (PBMSCs) needs further research. This study aimed to investigate the role of bFGF on the culture and expansion of PBMSCs in vitro. Firstly, arterial blood was collected from rats abdominal aorta. After mononuclear cells (MNCs) were separated with Ficoll separation fluid, MNCs were cultured in the DMEM medium without bFGF (served as control group) or with bFGF (10, 20 ng/mL, served as 10 or 20 ng/mL bFGF group). PBMSCs were obtained by adherent culture method. The third passage of PBMSCs was detected for the MSC surface markers and the effect of bFGF on the cell cycle of PBMSCs using flow cytometry. The effects of bFGF on colony formation, cell growth, and the expressions of cyclin D1, cyclin E, p21 and β-catenin were evaluated. PBMSCs showed no difference in morphology among the three groups. PBMSC clonies appeared 14 days after cultivation. Compared with the control group, the cell growth confluence of PBMSCs was obviously increased by 40% and 80% in groups treated with 10 ng/mL bFGF or 20 ng/mL bFGF respectively after culture of 21 days (all P<0.05). Compared with the group treated with 10 ng/mL bFGF, the confluence of PBMSCs in 20 ng/mL group was further increased by 28% (P<0.05). Cells of the third passage were positively stained for CD29 and CD90, while were negative for CD45. These results were consistent with the phenotypic characteristics of MSCs. Compared with the control group, the colony number of PBMSCs in the 10 ng/mL and 20 ng/mL bFGF groups was increased by 51% (P<0.05) and 92% (P<0.05), respectively. Compared with the 10 ng/mL group, the colony number of PBMSCs was further increased in 20 ng/mL group by 14% (P<0.05). The growth curve of PBMSCs showed that after 7 days of culture, the number of PBMSCs in 10 ng/mL bFGF group and 20 ng/mL bFGF group was increased by 41% (P<0.05) and 61% (P<0.05), respectively. Moreover, the cell number had a statistically significant difference between these two groups (P<0.05). Results from flow cytometry cell cycle showed that the numbers of PBMSCs in the G1 phase of experimental groups were significantly decreased as the concentration of bFGF increased when compared with the control group (P<0.05), whereas the number of PBMSCs in the S phase was significantly increased (P<0.05). Immunofluorescence experiments showed that, compared with the control group, bFGF significantly promoted the nuclear translocation and expression of β-catenin in PBMSCs. Compared with the 10 ng/mL group, the PBMSCs in 20 ng/mL bFGF group showed stronger nuclear translocation and expression of β-catenin. Western blot experiments showed that the levels of β-catenin and its target proteins cyclinD1 and cyclinE were significantly increased (all P<0.05), whereas expression of p21 was significantly decreased in PBMSCs in the bFGF groups in a concentration dependent pattern when compared with control group (P<0.05). The study firstly confirms that bFGF promotes the proliferation of PBMSCs by regulating the β-catenin signaling pathway, which may facilitate the aquisition of larger number of PBMSCs for stem cell engineering in vitro.