Chondrogenic differentiation of human adipose mesenchimal stem cells: Influence of a biomimetic gelatin genipin crosslinked porous scaffold

Human adipose derived stem cells have shown chondrogenic differentiation potential in cartilage tissue engineering in combination with biomimetic materials. In this study, the chondrogenic potential of a porous gelatin based scaffold genipin (GNP) crosslinked was investigated in human mesenchymal stem cells obtained from adipose tissue. Cells were cultured up to 4 weeks on the scaffold and on monolayer, MTT assay was performed to evaluate cell viability, light, and transmission electron microscopy were carried out to demonstrate cell proliferation, scaffold adhesion, and cell colonization inside the porous architecture of the biomaterial. The expression of chondrogenic markers such as SOX9, collagen type II, aggregan, and versican was investigated by Real Time PCR. Results showed an high cell viability, adhesion, and colonization of the scaffold. Real Time PCR data demonstrated an upregulation of all the chondrogenic markers analyzed. In conclusion, 3D gelatin GNP crosslinked porous scaffold provides an improved environment for chondrogenic differentiation of stem cells compared with cell monolayer culture system. Microsc. Res. Tech. 77:928–934, 2014. © 2014 Wiley Periodicals, Inc.     

Effects of human umbilical cord mesenchymal stem cells on co‐cultured ovarian carcinoma cells

Ovarian carcinoma is mainly treated by surgery aided by chemotherapy. If supplemented by stem cells treatment, its recurrence rate and mortality rate will be decreased. This is a new therapy. In this study, ovarian cancer cells were cultured together with umbilical cord mesenchymal stem cells (UCMSCs), and the interactions between them were observed. The results showed that the survival rates of UCMSCs increased to 83.8 ± 2.2% from 56.5 ± 5.5%, and the survival rates of ovarian cancer cells decreased to 16.2 ± 2.2% from 43.5 ± 5.5% with the progression of the cultural time from 24 to 96 hr. There was a significant difference between them (p < .05). It revealed that UCMSCs could inhibit the proliferation of ovarian cancer cells.     

Bones Morphogenic Protein‐4 and retinoic acid combined treatment comparative analysis for in vitro differentiation potential of murine mesenchymal stem cells derived from bone marrow and adipose tissue into germ cells

Nowadays, infertility is no longer considered as an unsolvable disorder due to progresses in germ cells derived from stem lineage with diverse origins. Technical and ethical challenges push researchers to investigate various tissue sources to approach more efficient gametes. The purpose of the current study is to investigate the efficacy of a combined medium, retinoic acid (RA) together with Bone Morphogenic Protein‐4 (BMP4), on differentiation of Bone Marrow Mesenchymal Stem Cells (BMMSCs) and adipose‐derived mesenchymal stem cells (ADMSCs) into germ cells. Murine MSCs were obtained from both Bone Marrow (BM) and Adipose Tissue (AT) samples and were analyzed for surface markers to get further verification of their nature. BMMSCs and ADMSCs were induced into osteogenic and adipogenic lineage cells respectively, to examine their multipotency. They were finally differentiated into germ cells using media enriched with BMP4 for 4 days followed by addition of RA for 7 days (11 days in total). Analyzing of differentiation potential of BMMSCs‐ and ADMSCs were performed via Immunofluorescence, Flowcytometry and Real time‐PCR techniques for germ cell‐specific markers (Mvh, Dazl, Stra8 and Scp3). Mesenchymal surface markers (CD90 and CD44) were expressed on both BMMSCs and ADMSCs, while endothelial and hematopoietic cell markers (CD31 and CD45) had no expression. Finally, all germ‐specific markers were expressed in both BM and AT. Although germ cells differentiated from ADMSCs showed faster growth and proliferation as well as easy collection, they significantly expressed germ‐specific markers lower than BMMSCs. This suggests stronger differentiation potential of murine BMMSCs than ADMSCs.     

Cell-surface ultrastructural changes during the in vitro neuron-like differentiation of rat bone marrow-derived mesenchymal stem cells

The neuron-like differentiation of bone marrow-derived mesenchymal stem cells (BMMSCs) has been extensively studied. However, the alternations of the cell-surface ultrastructures and the membrane tension/reservoir of the cells during this differentiation process are poorly understood. Therefore, atomic force microscopy (AFM) was utilized in this study to observe the cell-surface ultrastructural changes among rat bone marrow-derived mesenchymal stem cells (rBMMSCs), partially differentiated cells, and fully differentiated neuron-like cells. By analyzing the stiffness of plasma membranes, lamellipodial extensions, average heights of small membrane protrusions and relatively larger uplifted structures, and peak-peak spacing among protrusions and/or uplifted structures, we found that the membrane reservoir may potentially decrease upon the differentiation from rBMMSCs to partially differentiated cells and to fully differentiated neuron-like cells. The results may help to better understanding the membrane tension of various types of cells and related biological processes, such as membrane traffic, cell adhesion, motility, differentiation, among others. The data also implies that AFM may be a useful tool for evaluating membrane reservoir by imaging cell-surface ultrastructures.     

Three‐dimensional Co‐culture of hepatic progenitor cells and mesenchymal stem cells in vitro and in vivo

Introduction: Here we co‐cultured hepatic progenitor cells (HPCs) and mesenchymal stem cells (MSCs) to investigate whether the co‐culture environments could increase hepatocytes form. Methods: Three‐dimensional (3D) co‐culture model of HPCs and MSCs was developed and morphological features of cells were continuously observed. Hepatocyte specific markers Pou5f1/Oct4, AFP, CK‐18 and Alb were analyzed to confirm the differentiation of HPCs. The mRNA expression of CK‐18 and Alb was analyzed by RT‐PCR to investigate the influence of co‐culture model to the terminal differentiation process of mature hepatocytes. The functional properties of hepatocyte‐like cells were detected by continuously monitoring the albumin secretion using Gaussia luciferase assays. Scaffolds with HPCs and MSCs were implanted into nude mouse subcutaneously to set up the in vivo co‐culture model. Results: Although two groups formed smooth spheroids and high expressed of CK‐18 and Alb, hybrid spheroids had more regular structures and higher cell density. CK‐18 and Alb mRNA were at a relatively higher expression level in co‐culture system during the whole cultivation time (P < 0.05). Albumin secretion rates in the hybrid spheroids had been consistently higher than that in the mono‐culture spheroids (P < 0.05). In vivo, the hepatocyte‐like cells were consistent with the morphological features of mature hepatocytes and more well‐differentiated hepatocyte‐like cells were observed in the co‐culture group. Conclusions: HPCs and MSCs co‐culture system is an efficient way to form well‐differentiated hepatocyte‐like cells, hence, may be helpful to the cell therapy of hepatic tissues and alleviate the problem of hepatocytes shortage. Microsc. Res. Tech. 78:688–696, 2015. © 2015 Wiley Periodicals, Inc.     

Ultrastructural analysis of human bone marrow mesenchymal stem cells during in vitro osteogenesis and chondrogenesis

The main purpose of this article was to describe the morphology of mesenchymal stem cells (MSCs) differentiated in vitro towards osteogenic and chondrogenic lineages and to focus on the ultrastructural features associated with these processes. Human mononuclear cells (hMNC) were isolated, expanded, and analyzed for the expression of specific cell surface markers to demonstrate their stem cell characteristics. Human mononuclear cells were differentiated in vitro in an osteogenic and in a chondrogenic sense for 7, 14, 21, and 28 days. Subsequently, they were processed using electron microscopic analysis (FEISEM). Alizarin red and alcian blue staining were carried out to demonstrate the deposition of mineral salts and proteoglycans in the extracellular matrix. Undifferentiated MSCs showed a cell surface covered by filopodia and ondulopodia. During differentiation, the MSCs changed their shape from a round to a fibroblastic-like shape. At the end of the differentiation, several filaments with a parallel orientation in the osteogenic samples as well as a network organization in the chondrogenic samples were detected in the extracellular spaces. This study demonstrated that there are morphological features associated with the undifferentiated and differentiated states of the MSCs, which could be utilized as new parameters for identifying and classifying these cells.     

Ultrastructural characteristics of ovine bone marrow‐derived mesenchymal stromal cells cultured with a silicon stabilized tricalcium phosphate bioceramic

Bioceramics are being used in experimental bone engineering application in association with bone marrow derived mesenchymal stem cells (BM‐MSCs) as a new therapeutic tool, but their effects on the ultrastructure of BM‐MSCs are yet unknown. In this study we report the morphological features of ovine (o)BM‐MSCs cultured with Skelite, a resorbable bioceramic based on silicon stabilized tricalcium phosphate (SiTCP), able to promote the repair of induced bone defect in sheep model. oBM‐MSCs were isolated from the iliac crest, cultured until they reached near‐confluence and incubated with SiTCP. After 48 hr the monolayers were highly damaged and only few cells adhered to the plastic. Thus, SiTCP was removed, and after washing the cells were cultured until they became confluent. Then, they were trypsinizated and processed for transmission electron microscopy (TEM) and RT‐PCR analysis. RT‐PCR displayed that oBM‐MSCs express typical surface marker for MSCs. TEM revealed the presence of electron‐lucent cells and electron‐dense cells, both expressing the CD90 surface antigen. The prominent feature of electron‐lucent cells was the concentration of cytoplasmic organelles around the nucleus as well as large surface blebs containing glycogen or profiles of endoplasmic reticulum. The dark cells had a multilocular appearance by the presence of peripheral vacuoles. Some dark cells contained endocytic vesicles, lysosomes, and glycogen aggregates. oBM‐MSCs showed different types of specialized interconnections. The comparison with ultrastructural features of untreated oBM‐MSCs suggests the light and dark cells are two distinct cell types which were differently affected by SiTCP bioceramic. Skelite cultured ovine BM‐MSCs display electron‐dense and electron‐lucent cells which are differently affected by this bioceramic. This suggests that they could play a different role in bioceramic based therapy.     

Role of spermatogonial stem cells extract in transdifferentiation of 5‐Aza‐2′‐deoxycytidine‐treated bone marrow mesenchymal stem cells into germ‐like cells

As one of the induced pluripotent stem cells (iPSCs) methods, spermatogonial stem cells (SSC_S) extract is considered as new approach in stem cell therapy of infertility. 5‐aza‐2′‐deoxycytidine (5‐aza‐dC) inhibits methyltransferase enzyme, and induces gene reprogramming; herein, the effects of SSC_S extract incubation in 5‐aza‐dC‐treated bone marrow mesenchymal stem cells (BMMSCs) has been surveyed. BMMSCs were isolated from femurs of three to four weeks old male NMRI mice, and the cells at passage three were treated with 2 µM 5‐aza‐dC for 72 hours. SSCs were isolated, cultured, and harvested at passage three to collect SSC_S extract; BMMSCs were then incubated with SSC_S extract in the three time periods: 72 hours, one week and two weeks. There were five groups: control, sham, extract, 5‐aza‐dC and extract‐5‐aza‐dC. After one week of incubation, flow cytometry and real‐time polymerase chain reaction (PCR) exhibited high levels of expression for β1‐ and α6‐integrins and promyelocytic leukaemia zinc finger (PLZF) in extract and extract‐5‐aza‐dC groups (P < 0.05 vs. control and 5‐aza‐dC), and cells in these two groups had two forms of morphology, round and fusiform, similar to germ‐like cells. 5‐aza‐dC had no significant effects during the three time periods of evaluation. These data disclose the effectiveness of SSCs extract incubation in transdifferentiation of BMMSCs into germ‐like cells; this strategy could introduce a new approach for treatment of male infertility in clinic. Microsc. Res. Tech. 79:365–373, 2016. © 2016 Wiley Periodicals, Inc.     

<i>miR-103-3p</i> regulates the differentiation of bone marrow mesenchymal stem cells in myelodysplastic syndrome

The pathogenesis of myelodysplastic syndrome (MDS) may be related to the abnormal expression of microRNAs(miRNAs), which could influence the differentiation capacity of mesenchymal stem cells (MSCs) towards adipogenic andosteogenic lineages. In this study, exosomes from bone marrow plasma were successfully extracted and identified.Assessment of miR-103-3p expression in exosomes isolated from BM in 34 MDS patients and 10 controls revealed its0.52-fold downregulation in patients with MDS compared with controls (NOR) and was downregulated 0.55-fold inMDS-MSCs compared with NOR-MSCs. Transfection of MDS-MSCs with the miR-103-3p mimic improved osteogenicdifferentiation and decreased adipogenic differentiation in vitro, while inhibition of miR-103-3p showed the oppositeresults in NOR-MSCs. Thus, the expression of miR-103-3p decreases in MDS BM plasma and MDS-MSCs, significantlyimpacting MDS-MSCs differentiation. The miR-103-3p mimics may boost MDS-MSCs osteogenic differentiation whileweakening lipid differentiation, thereby providing possible target for the treatment of MDS pathogenesis.     

Astragaloside IV improves melanocyte differentiation from mouse bone marrow mesenchymal stem cells

Vitiligo results in an autoimmune disorder destructing skin pigment cells, melanocytes (Mcs). This study aimedto investigate whether Astragaloside IV (AIV) could efficiently induce differentiation of bone marrow mesenchymal stemcells (BMMSCs) into Mcs. BMMSCs were induced and differentiated into Mcs with 0.1, 0.2, and 0.4 mg/L AIV during150-day. Morphologic changes of differentiated cells were observed. Levels of some melanocytic specific genes (TRP-1,TRP-2, MART-1, Mitf) were measured with quantitative polymerase chain reaction (qPCR) at 90, 120, and 150 daysof induction. After 90-day induction, the differentiated cells with 0.4 mg/L AIV demonstrated the typical morphologyof Mcs, positive 3,4 dihydroxyphenylalanine staining, and positive staining of TRP-1, TRP-2, MART-1, and Mitf.After 90- and 120- days’ induction with 0.4 mg/L AIV, TRP-1 expression was significantly elevated (p < 0.01), andTRP-2 expression was significantly increased in 0.4 mg/L AIV-treated group compared to negative control (p < 0.01),0.1 mg/L (p < 0.01), and 0.2 mg/L (p < 0.01) AIV-treated groups. Moreover, MART-1 expression was significantlyup-regulated in 0.4 mg/L AIV-treated group compared to negative control, but without difference compared to 0.1mg/L (p > 0.05) and 0.2 mg/L (p > 0.05) AIV-treated groups. During 90 to 150- day induction, there were nosignificant differences for Mitf levels between AIV-treated groups and negative control (p > 0.05). In conclusion,90-day induction with 0.4 mg/L AIV up-regulated TRP-1, TRP-2, and MART-1 expression, indicating that AIV canefficiently induce Mcs differentiation from BMMSCs. These results provide experimental and theoretic evidence forAIV application in clinical vitiligo repigmentation treatment.     

Synchrotron radiation X‐ray micro‐fluorescence: Protocol to study mesenchymal stem cells

The micro‐X‐ray fluorescence by synchrotron radiation (μ‐XRF) is a method to determine the composition of tissues without destroying the samples. However, this technique has never been used for the analysis of mesenchymal stem cells (MSC). This study compared different protocols for fixing, storing, preserving, and establishing the correct numbers of dental derived MSC submitted to μ‐XRF analysis. Stem cells were obtained from human dental tissue. After cell expansion, and MACS isolation, the samples were fixed and the following quantities of cells 1 × 10⁴ to 1 × 10⁷ were divided in two groups: G1: fixed in 4% paraformaldehyde diluted in phosphate‐buffered saline solution, and G2: fixed in 4% paraformaldehyde diluted in MilliQ water. The G1 cells showed precipitation of chemical components from the solution resulting in the formation of salt crystals while G2 cells were clear and almost transparent in the sample holder. With regards to cells concentration, the best results occurred when four droplets of 1 × 10⁷ cells were analyzed. This work shows that to identify and study the distribution of trace elements in MSC by μ‐XRF, the best protocol is fixation in 4% paraformaldehyde diluted with MilliQ water at 4°C and a concentration of four incremental droplets of 1 × 10⁷ cells. Microsc. Res. Tech. 79:149–154, 2016. © 2016 Wiley Periodicals, Inc.     

Ultrastructural study of mouse adipose‐derived stromal cells induced towards osteogenic direction

We investigated the ultrastructural characteristics of mouse adipose‐derived stem/stromal cells (ASCs) induced towards osteogenic lineage. ASCs were isolated from adipose tissue of FVB‐Cg‐Tg(GFPU)5Nagy/J mice and expanded in monolayer culture. Flow cytometry, histochemical staining, and electron microscopy techniques were used to characterize the ASCs with respect to their ability for osteogenic differentiation capacity. Immunophenotypically, ASCs were characterized by high expression of the CD44 and CD90 markers, while the relative content of cells expressing CD45, CD34 and CD117 markers was <2%. In assays of differentiation, the positive response to osteogenic differentiation factors was observed and characterized by deposition of calcium in the extracellular matrix and alkaline phosphatase production. Electron microscopy analysis revealed that undifferentiated ASCs had a rough endoplasmic reticulum with dilated cisterns and elongated mitochondria. At the end of the osteogenic differentiation, the ASCs transformed from their original fibroblast‐like appearance to having a polygonal osteoblast‐like morphology. Ultrastructurally, these cells were characterized by large euchromatic nucleus and numerous cytoplasm containing elongated mitochondria, a very prominent rough endoplasmic reticulum, Golgi apparatus and intermediate filament bundles. Extracellular matrix vesicles of variable size similar to the calcification nodules were observed among collagen fibrils. Our data provide the ultrastructural basis for further studies on the cellular mechanisms involved in osteogenic differentiation of mouse adipose‐derived stem/stromal cells. Microsc. Res. Tech. 79:557–564, 2016. © 2016 Wiley Periodicals, Inc.     

Effects of TGF‐β1 on mineralization mediated by rat calvaria‐derived osteogenic cells

In this study, we have analyzed the viability and cell growth, as well as, the mineralization of extracellular matrix (ECM) by alizarin red and von Kossa staining of calvaria‐derived osteogenic cultures, treated with TGF‐β1 alone or associated with Dex comparing with acid ascorbic (AA) + β‐glicerophosphate (βGP) (positive mineralization control). The expression of the noncollagenous proteins bone sialoprotein (BSP), osteopontin (OPN) and fibronectin (FN) were evaluated by indirect immunofluorescence. In addition, the main ultrastructural morphological findings were assessed by transmission electron microscopy. Osteogenic cells were isolated of calvaria bone from newborn (2‐day‐old) Wistar rats were treated with TGF‐β1 alone or with dexamethasone for 7, 10, and 14 days. As positive mineralization control, the cells were supplemented only with AA+ βGP. As negative control, the cells were cultured with basal medium (α‐MEM + 10%FBS + 1%gentamicin). The treatment with TGF‐β1, even when combined with Dex, decreased the viability and cell growth when compared with the positive control. Osteoblastic cell cultures were positive to alizarin red and von Kossa stainings after AA + βGP and Dex alone treatments. Positive immunoreaction was found for BSP, OPN and FN in all studied treatments. Otherwise, when the cell cultures were supplemented with TGF‐β1 and TGF‐β1 + Dex, no mineralization was observed in any of the studied periods. These present findings suggest that TGF‐β1, in the studied in vitro doses, inhibits the proliferation and differentiation of osteoblastic cells by impairment of nodule formation.     

The antioxidant trolox inhibits aging and enhances prostaglandin E-2 secretion in mesenchymal stem cells

Mesenchymal stem cells (MSCs) have been widely used in regenerative medicine and clinical therapy due to their capabilities of proliferation, differentiation, and immune regulation. However, during in vitro expansion, MSCs are prone to aging, which largely limits their application. Prostaglandin E-2 (PGE-2) is a key effector secreted by MSCs to exert immunomodulatory effects. By screening the compound library for PGE-2 secretion, the antioxidant trolox was verified as a stimulator of MSCs to secrete PGE-2. The effect of antioxidant trolox on biological characteristics of MSCS, including aging, proliferation, and gene expression, was examined. The results demonstrated that trolox can resist aging, promote proliferation, and enhance PGE-2 secretion of MSCs without affecting their surface marker expression. Furthermore, trolox treatment up-regulates miR-17-92 clusters in MSCs and may contribute to its anti-aging effects. Thus, trolox addition might be beneficial for MSCs expansion and their application.     

LncRNA <i>ZFAS1</i> regulates cardiomyocyte differentiation of human embryonic stem cells

Background: Cardiomyocytes derived from human embryonic stem cells (hESCs) are regulated by complex and stringent gene networks during differentiation. Long non-coding RNAs (lncRNAs) exert critical epigenetic regulatory functions in multiple differentiation processes. However, the involvement of lncRNAs in the differentiation of hESCs into cardiomyocytes has not yet been fully elucidated. Here, we identified the key roles of ZFAS1 (lncRNA zinc finger antisense 1) in the differentiation of cardiomyocytes from hESCs. Methods: A model of cardiomyocyte differentiation from stem cells was established using the monolayer differentiation method, and the number of beating hESCs-derived cardiomyocytes was calculated. Gene expression was analyzed by quantitative real-time PCR (qRT-PCR). Immunofluorescence assays were performed to assess the expression of cardiac troponin T (cTnT) and α-actinin protein in cardiomyocytes. Results: qRT-PCR showed that ZFAS1 expression in the mesoderm was significantly higher than that in embryonic stem cells, cardiac progenitor cells, and cardiomyocytes. Knockdown of ZFAS1 inhibited cardiomyocyte differentiation from hESCs, which was characterized by reduced expression of the cardiac-specific markers cTnT, α-actinin, myosin heavy chain 6 (MYH6), and myosin heavy chain 7 (MYH7). In contrast, ZFAS1 overexpression remarkably increased the percentage of spontaneously beating cardiomyocytes. In terms of the mechanism, we found that ZFAS1 is an antisense lncRNA at the 5′ end of the protein-coding gene ZNFX1. Knockdown of ZFAS1 could increase the mRNA expression level of ZNFX1. Furthermore, qRT-PCR demonstrated that the silencing of ZNFX1 led to an increase in cardiac-specific markers that predicted the promotion of cardiomyocyte differentiation. Conclusion: Altogether, these data suggest that lncRNA-ZFAS1 is required for cardiac differentiation by functionally inhibiting the expression of ZNFX1, which may provide a reference for the treatment of heart disease to a certain extent.     

Therapeutic application of mesenchymal stem cells-derived extracellular vesicles in colorectal cancer

Colorectal cancer (CRC) is the third most common cancer and the leading cause of cancer death globally. Resistance to therapy is a challenge for CRC treatment. Mesenchymal stem cells (MSCs) have become one of the furthermost effective approaches for tumor treatment due to their specific feature; however, their therapeutic function is controversial. Recently, extracellular vesicles (EVs) derived from MSCs (MSCs-EVs) have attracted extensive research attention due to their promising role in CRC treatment. EVs are cell-derived vesicles that transfer different biomolecules between cells, contributing to intracellular communication. MSCs-EVs can suppress CRC by delivering therapeutic agents to tumor cells. Several studies indicate that MSCs-EVs can serve as a drug delivery system for the treatment of different cancers. Various methods are used to modify (engineer) MSCs-EVs for loading therapeutic agents. Modified MSCs-EVs have improved specificity, targeting ability, and immunogenicity compared to synthetic carriers. Furthermore, CRC-EVs participate in regulating different cells, such as immune cells, fibroblasts, and endothelial cells, promoting tumorigenesis. MSCs-EVs-based therapy indicates a high potential in the treatment of cancer; however, the majority of studies have been conducted in the pre-clinical, and their clinical applications need further scrutiny. In this review, we describe the biogenesis of EVs, focusing on the effect of MSCs-EVs on CRC cells and CRC-derived EVs on other cells. Furthermore, MSCs-EVs as a drug delivery system for cancers is also reviewed, and perspectives regarding the therapeutic application of MSCs-EVs are discussed.     

Human umbilical cord blood mesenchymal stem cells conditioned media inhibits hypoxia-induced apoptosis in H9c2 cells by activation of the survival protein Akt

This work aimed to study the beneficial role of human umbilical cord blood-derived mesenchymal stem cellconditioned medium (MSC-CM) in hypoxia-induced apoptosis in H9c2 cardiomyoblasts, in which the serine/heroinekinases (Akt) pathway would be involved. For this, CM was collected by culturing MSCs in serum-free DMEMmedium for 24 h, and paracrine factors were analyzed by protein chip. H9c2 cells were divided into the followinggroups: control group, hypoxia group, MSC-CM intervention group (CM group), MSC-CM + Akt phosphorylationinhibitor (LY294002) group (LY group). Apoptosis of the H9c2 cells was tested with chromatin dye Hoechst 33342and FITC-conjugated Annexin V apoptosis detection kit by flow cytometer after a hypoxia/serum deprivation (H/SD)for 24 h. The apoptosis-related proteins were evaluated by Western blot. MSC-CM displayed significantly elevatedlevels of growth factors, anti-inflammatory, and anti-apoptosis cytokines. On Hoechst 33342 apoptosis staining, theH9c2 cell morphology displayed a lower proportion of apoptosis in the CM group than those in the hypoxia group,while apoptosis was increased in LY group. Flow cytometer analysis revealed the apoptosis ratio in the CM group waslower than the hypoxia group (12.34 ± 2.00% vs. 21.73 ± 2.58%; p < 0.05), while the LY group was significantly higher(22.54 ± 3.89%). Active caspase-3 expression was increased in hypoxia group than control group (p < 0.05), butdecreased in CM group (p < 0.01). Umbilical cord blood-derived mesenchymal stem cell-conditioned media secretemultiple paracrine factors that are able to inhibit hypoxia-induced H9c2 cardiomyoblasts apoptosis, and in which theactivation of Akt phosphorylation is involved to achieve the protective effect.     

神经干细胞体外诱导分化的研究进展

神经干细胞是近年来脑科学研究的热点,其自我更新和多向分化的潜能为中枢神经系统疾病的治疗提供了可能,但如何使神经干细胞向特定的方向分化却一直是研究的难点.本文对神经干细胞体外的诱导分化因素及分化过程中的相关蛋白质组的研究做一综述.