Effect of ginsenoside Rg1 on the amyloid protein precursor and neprilysin expression induced by lipopolysaccharide in C6 cell line

AIM: This study was designed to investigate the effect of ginsenoside Rg1 on the amyloid β-protein precursor (APP) and neprilysin (NEP)expression induced by lipopolysaccharide (LPS) in C6 cell line in order to discover effectual Alzheimer's disease (AD)-treated drugs. METHODS: MTT colorimetric analysis was used to measure the survival rate of C6 cultured with ginsenoside Rg1 at different concentrations (2.5, 5, 10 and 20 μmol·L^-1) and LPS (100 mg·L^-1). The expression of APP and NEP mRNA was measured by RT-PCR. RESULTS: LPS decreased the survival rate of C6, furthermore, the increase in APP expression and the decrease in NEP expression were observed. On the other hand, the above alteration induced by LPS was reversed by ginsenoside Rg1. CONCLUSION: This study demonstrates that LPS can cause cell damage, the increase in APP expression and the decrease in NEP expression. Ginsenoside Rg1 can exert a neuroprotective action, protect C6 cells against LPS-induced injury via inhibiting APP expression and increasing NEP expression.     

Effects of GATA6 silencing mediated by lentivirus on apoptosis of human liver cancer Huh-7 cells

AIM: To explore the effect of GATA6 gene silencing on apoptosis of hepatocellular carcinoma Huh-7 cells. METHODS: RNA interference vectors of the target gene GATA6 mediated by lentivirus were constructed in vitro to transfect the hepatocellular carcinoma cell line Huh-7. The apoptotic rate of transfected cells was measured by flow cytometry. The protein expression of GATA6, NF-κB and Bcl-2 in transfected cells was determined by Western blotting. RESULTS: The transfection efficiency was 57.4%. The mRNA and protein expression of GATA6 reduced significantly after the carcinoma cell line Huh-7 being transfected by RNA interference vectors mediated by lentivirus. The apoptotic rate of the carcinoma cells with silent GATA6 gene was significantly increased (P<0.05). The protein expression levels of NF-κB and Bcl-2 were also significantly decreased. CONCLUSION: Lentiviral vector-mediated RNA interference of GATA6 has an inhibitory effect on the expression of the gene itself, and promotes the apoptosis of hepatocellular carcinoma cells. Regulation of the apoptosis-related protein expression by the NF-κB signaling to influence the proliferation and apoptosis of hepatocellular carcinoma cells might be one of the possible mechanisms.     

Construction of a lentiviral RNA interference vector targeting rat myocardin and its effect on vascular smooth muscle cell differentiation

AIM: To construct a lentiviral RNA interference(RNAi)vector targeting rat myocardin mRNA and to investigate its effect on the differentiation of vascular smooth muscle cells(VSMCs).METHODS: Three pairs of dsDNA targeting rat myocardin mRNA were designed, synthesized and cloned into lentiviral vector pGCSIL-GFP to generate pGCSIL-GFP-shMyocd lentvirus. A Flag-tagged myocardin-overexpression vector pEGFP-N1-Myocd was constructed with pEGFP-N1/X124G. After these two vectors were cotransfected into 293T cells, the flag protein was assessed by Western blotting to analyze the knockdown effect of pGCSIL-GFP-shMyocd. The expression of myocardin and SM22α was also detected by RT-PCR and Western blotting after the pGCSIL-GFP-shMyocd viruses were transfected into primary cultured rat aortal VSMCs.RESULTS: The rat myocardin lentviral RNAi vector pGCSIL-GFP-shMyocd and myocardin-overexpression vector pEGFP-N1-Myocd were successfully constructed. After these two kinds of vectors were cotransfected into 293T cells,the No.1 interfering vector displayed the highest inhibitory effect on flag expression.After the No.1 lentvirus at the titer of 1×10¹² TU/L was transfected into VSMCs, the myocardin and SM22α expression was significantly attenuated. CONCLUSION: The lentiviral pGCSIL-GFP-shMyocd RNAi vector is successfully constructed, which is useful for further study regarding the molecular mechanism of the phenotypic switching in VSMCs under special pathological conditions such as atherosclerosis. Inhibition of myocardin expression in VSMCs leads to the decrease in the expression of differentiation marker, and implies a crucial role of myocardin in VSMCs differentiation.     

Transfection of calcitonin gene-related peptide mediated by lentivirus vector in vitro and its effects on cardiac stem cell viability

AIM: To investigate the effect of calcitonin gene-related peptide (CGRP)transfection into c-kit^pos cardiac stem cells (c-kit⁺CSCs) on the cell viability. METHODS: Under the sterile condition, the auricles of SD rats were taken out,and then c-kit⁺CSCs were collected through enzyme digestion and immunomagnetic bead separation (MACS). The cells were identified by flow cytometry. c-kit⁺CSCs were transfected with enhanced green fluorescent protein CGRP lentiviral vector (Lv-EGFP-CGRP) or enhanced green fluorescent protein lentiviral vector (Lv-EGFP). The cells were randomly divided into Lv-EGFP-CGRP-CSCs group, Lv-EGFP-CSCs group and CSCs group. The transfection was observed under the fluorescence microscope. The transfection efficiency was detected by flow cytometry. The CGRP protein secretion in the cell culture supernatants was detected by ELISA. The viability of c-kit⁺CSCs transfected with Lv-EGFP-CGRP or Lv-EGFP was measured by CCK-8 assay. RESULTS: c-kit⁺CSCs were isolated and cultured successfully. The expression positive rate of c-kit was 91.0% and the expression positive rates of CD45 and CD34 were 4.5% and 4.0%, respectively. After transfected with lentivirus for 48 h, the stable fluorescence in c-kit⁺CSCs was observed under fluorescence microscope. The transfection efficiency were 80% when MOI was 20. The level of CGRP was significantly increased in Lv-ECFP-CGRP-CSCs group compared with Lv-EGFP-CSCs group and CSCs group (P<0.05). Meanwhile, transfection with lentiviral vector in each group did not affect the viability of c-kit⁺CSCs. CONCLUSION: Transfection of Lv-EGFP-CGRP into c-kit⁺CSCs was successful. The secretion of CGRP was found in the transfected c-kit⁺CSCs and the viability was not changed after transfection. CGRP-modified c-kit⁺CSCs may play a role in treating myocardial infarction.     

Effects of p38 MAPK gene knockout on arsenite-induced cell apoptosis

AIM: To investigate the role of p38 mitogen-activated protein kinase (MAPK) in the cell apoptosis induced by arsenite.METHODS: After the treatment with or without arsenite, p38+/+ and p38-/- cells were fixed with paraformaldehyde and stained with DAPI. The nuclear morphological changes were observed under a fluorescence microscope. p38+/+ and p38-/- cells were double-stained with Annexin V-FITC and PI, and the ratios of apoptotic cells were detected by flow cytometry.RESULTS: With the stimulation of arsenite, typical apoptotic morphological changes appeared in most p38-/- cells, yet only a few p38+/+ cells showed nucleus condensation. Consistently, the ratio of apoptotic p38-/- cells induced by arsenite significantly increased in comparison with that in the untreated cells (P<0.01), and also much higher than that in p38+/+ cells stimulated with arsenite (P<0.01).CONCLUSION: p38 gene knockout leads to a decrease in cellular resistance to stress of arsenite, which produces a proapoptotic state. p38 MAPK may play an important role on the enhancement of cell adaptive capability to harmful stresses.     

Effects of p21siRNA on cell cycle uncoupling and apoptosis

AIM:To investigate the effects of P21 protein on cell cycle uncoupling and cell apoptosis with RNA interference assay. METHODS:The expression of P21 protein in HeLa cells was induced by mitomycin (MMC). Lipofect transfection assay was used to take the p21 siRNA into HeLa cells and MMC was given 48 h after transfection. FCM assay was applied to detect the expression of P21 and ratio of polyploid cells and apoptosis. RESULTS:p21 siRNA plasmid interfered the expression of P21 protein in HeLa cells. The number of 2 haploid cells was decreased obviously (P<0.01). The number of 4 haploid and 8 haploid cells was increased significantly (P<0.01) compared with control plasmid 24 and 48 h after MMC was given. CONCLUSION:p21 siRNA silenced the P21 protein and cell death in HeLa cells was induced by p53-independent pathway in the condition of lower expression of P21 protein. The mechanism may be related to cell cycle uncoupling and apoptosis by p53-independent pathway.     

Effects of anti-leukemia by antisense c-myc by retrovirus vector

AIM: To study the role of c-myc oncogene in L6565 leukemia oncogenesis and the effects of therapy by inhibition of its expression with antisense c-myc. METHODS: A recombinant retroviral vector containing antisense c-myc of the murine (pGNCas) was constructed and then transfected into PA317 cells by the method of calcium phosphate precipitation. L6565 clone cells were infected with retrovirus particles. Stable integretion of antisense c-myc was shown by PCR. The change of the malignance and phenotype of L6565as were detected by the examination of the growth, morphology, cells cycle, agar assay and expression of c-myc. RESULTS: The shape of most L6565as cells became spherical. The growth of L6565as was inhibited compared to control cells. The analysis of cells cycle: L6565as cells were arrest in G₀/G₁ phase, decreased in S phase. The ability of L6565as cells to form colony in soft agarose was significantly suppressed. c-myc in L6565as cells was lowly expressed. CONCLUSION: (1)c-myc plays a critical role in L6565 leukemia oncogenesis; (2)Inhibition of expression of c-myc makes partly reversion of malignant phenotype of L6565 murine leukemia clone cells.     

Effects of baicalin on CA46 cell proliferation inhibition and apoptosis induction

AIM: To investigate the effects of baicalin on proliferation inhibition and apoptosis induction in human Burkitt lymphoma cell line CA46 and to explore its underlying mechanisms. METHODS: CA46 cells were exposed to baicalin at different dosages and its proliferation inhibition was detected by MTT assay. The ability of baicalin to induce CA46 cell apoptosis was examined by Annexin V-FITC/PI double staining analysis, TUNEL labeling method and DNA fragmentation. The mRNA expressions of c-myc and bcl-2 were detected by RT-PCR, and the protein expressions of c-Myc, Bcl-2, caspase-3 precursor (procaspase-3) and poly ADP-ribose polymerase (PARP) were detected by Western blotting. RESULTS: Baicalin remarkably inhibited the CA46 cell proliferation, with an IC50 value of 10 μmol/L. Apoptosis was remarkably induced by baicalin in a dose-dependent manner, and its earlier and later stages were detected by annexin V-FITC/PI double staining analysis, TUNEL labeling method and DNA fragmentation, respectively. Furthermore, RT-PCR showed that the mRNA expressions of c-myc and bcl-2 in treated CA46 cells decreased in a time-dependent manner. Western blotting showed that the protein expressions of c-Myc, Bcl-2, procaspase-3 and PARP (116 kD) in baicalin treated CA46 cells were down-regulated in a time-dependent manner, while the expression of PARP(85 kD) was up-regulated. CONCLUSION: Baicalin efficiently induces proliferation inhibition and apoptosis in CA46 cells, which may be related with the down-regulation of c-Myc and Bcl-2 expressions, as well as the up-regulation of caspase-3 activity.     

Effects of EBV infection on growth and apoptosis of nasopharyngeal carcinoma cell line

AIM: To explore the effect of EBV infection on growth and apoptosis of nasopharyngeal carcinoma(NPC) cell line.METHODS: NPC cell line CNE1 was directly infected by Epstein Barr virus (EBV). The expression of EBV-latent membrane protein 1 (EBV-LMP1) and bcl-2 were detected by immunohistochemistry method (LSAB). The growth of NPC cells was identified by MTT method. Apoptotic carcinoma cells were detected by flow cytometry analysis and the terminal deoxynucletidyl transferase-medicated dUTP-biotin nick end labeling (TUNEL) methods. RESULTS: EBV-LMP1 was positive in CNE1 infected by EBV(E-CNE1). Compared with CEN1, the growth of E-CNE1 apparently increased (P＜0.01). No apoptotic carcinoma cells were detected and bcl-2 postive cells were 2%~3% respectively in 2 kinds of NPC cells.CONCLUSION: Growth of NPC cells is enhanced by EBV infection and EBV-LMP1 expression, but no influence on expression of bcl-2 and apoptosis of NPC cells.     

Effects of EBV infection on growth and apoptosis of nasopharyngeal carcinoma cell line

AIM:To explore the effect of EBV infection on growth and apoptosis of nasopharyngeal carcinoma(NPC)cell line.METHODS:NPC cell line CNE1 was directly infected by Epstein Barr virus(EBV).The expression of EBV-latent membrane protein 1(EBV-LMP1)and bcl-2 were detected by immunohistochemistry method(LSAB).The growth of NPC cells was identified by MTT method.Apoptotic carcinoma cells were detected by flowcytometry analysis and the terminal deoxynucletidyl transferase-medicated dUTP-biotin nick end labeling(TUNEL)methods.RESULTS:EBV-LMP1 was positive in CNE1 infected by EBV(E-CNE1).Compared with CEN1, the growth of E-CNE1 apparently increased(P<0.01).No apoptotic carcinoma cel s were detected and bcl-2 postive cells were 2%~3%respectively in 2 kinds of NPC cells.CONCLUSION:Growth of NPC cells is enhanced by EBV infect ion and EBV-LMP1 expression, but no influence on expression of bcl-2 and apoptosis of NPC cells.     

Construction of short hairpin RNA lentiviral vector targeting MAG gene and its silencing effect on MAG gene

AIM：To construct lentiviral vector-based short hairpin RNA (shRNA) targeting myelin-associated glycoprotein (MAG) gene and to evaluate its inhibitory effect on the expression of MAG gene. METHODS：Three shRNA fragments targeting MAG gene (shRNA1, shRNA2 and shRNA3) were designed and cloned into lentiviral vector pWPI. The three recombinant plasmids were identified by enzyme digestion and sequencing. Positive plasmids were co-transfected with pCDNA3-MAG-FLAG into 293T cells, and the most effective shRNA for knockdown of MAG gene was screened by Western blotting. Cells transfected with empty pWPI served as a control. Oligodendrocytes were infected with recombinant lentivirus that was produced by 293T packaging cells co-transfected with the most effective shRNA, pAX2 and pMD2G. After 48 h, the expression of MAG protein was measured by Western blotting. RESULTS：The MAG shRNA lentiviral vectors were confirmed by double enzyme digestion and sequencing, and shRNA2 showed the highest inhibitory efficacy among the three shRNA fragments. Recombinant lentivirus carrying shRNA-2 markedly decreased the expression of MAG protein in oligodendrocytes. CONCLUSION：Lentiviral vector-based shRNA targeting MAG gene specifically knocks down the gene expression, which provides a useful tool for investigating the role of MAG-specific shRNA in regulating myelination of central nerve system.     

Lethal effect of VEGFR2shRNA on HL60 cells in vitro using lentiviral vector

AIM: To look for harmfulless anti-leukemia drug with selective high performance, lethal effect of small hairpin RNA (shRNA) on VEGFR₂ gene expression of tumor cell line HL60 in vitro.METHODS: The most effective VEGFR₂ siRNA was designed and screened. The shRNA oligo was designed and pU6/VEGFR₂ entry clone was constructed. HL60 was transfected transiently and vascular endothelial growth factor receptor 2(VEGFR₂) expression was tested with MTT assay, RT-PCR and Western blotting. The expression clone was constructed and cotransfected with ViraPowerTM Packaging Mix into 293FTTM cells to produce Lentiviral vectors harboring Lenti6/shVEGFR₂. The virion supernatant was added into HL60 cells and VEGFR₂ gene inhibitory effect was determined. RESULTS: The inhibitory rates of VEGFR₂ siRNA c were high. VEGFR₂ expression in HL60 was inhibited by using pU6/VEGFR₂ entry clone constructed with shRNA and pENTRTM/U6. For HL60 cells, the inhibitory rate was 84.9%. The expression of VEGFR₂ mRNA and protein decreased significantly. 48 hours after transfection of pU6/shVEGFR₂ entry clone and transduction of Lenti6/shVEGFR₂ expression clone, the cell inhibitory rates were similar. Cell growth inhibitory rate of entry clone descended rapidly after this time point, the expression clone changed slowly, reaching the peak at 96 hours, dropped slightly, having no significance deviation. CONCLUSION: in vitro, VEGFR₂ shRNA using lentiviral vector blocks VEGF/VEGFR₂ self-secretion in HL60 cells, which inhibits leukemia development.     

Effects of Fas,NF-κB and caspases on microvascular endothelial cell apoptosis induced by TNFα

AIM:To study the apoptotic effect of TNFα on rat pulmonary microvascular endothelial cells(PMVEC)and the role of Fas, NF-κB in its mechanism. METHODS: Apoptosis of PMVEC was analyzed and quantitated with TUNEL, flow cytometer. Northern blot was applied to assess the influence of TNFα on PMVEC Fas expression. Fas antibody was used to investigate the apoptotic effect of Fas on PMVEC. Activation of caspase-8 was examined by Western blot. Expression of caspase-3 was analyzed with histo-immunochemical staining. RESULTS:Growth curve showed that TNFα suppressed endothelial cell proliferation in a dose-dependent manner. After treatment with 5×10⁶U/LTNFα, apoptotic rate was 14.0%±3.1% detected with TUNEL, and 13.1% with flow cytometer. When the cells were co-cultured with TNFα and APDC, an NF-κB inhibitor, less cells were viable and more cells were positively stained with TUNEL. Fas expression in PMVEC was elevated after TNFα treatment. Co-culturing with Anti-Fas antibody aggravated PMVEC apoptosis. Caspase-8 activity and caspase-3 expression was elevated. Caspase-3 inhibitor significantly ameliorated PMVEC apoptosis. CONCLUSION: Large dose of TNFα(5×10⁶U/L) can induce apoptosis in rat PMVEC. NF-κB has an anti-apoptotic effect in PMVEC. TNFα up-regulates Fas expression in PMVEC, and the latter takes a part in apoptosis. Caspase-8 and caspase-3 are involved in PMVEC apoptosis induced by TNFα.     

Effects of PDGFRα on melanocyte apoptosis induced by hydrogen peroxide

AIM: To investigate the effects of platelet-derived growth factor receptor α (PDGFRα) on melanocyte apoptosis induced by hydrogen peroxide (H₂O₂). METHODS: Melanocyte PIGI was used as the research object. After exposed to H₂O₂ at different concentrations, the cell viability was detected by MTT assay. The PIGI cells were transfec-ted with empty vector pCMV6 or PDGFRα over-expression vector pCMV6-PDGFRα. The transfection efficiency was determined by RT-qPCR and Western blot. The effect of H₂O₂ on the viability of the PIGI cells after over-expression of PDGFRα was measured by MTT assay. The cell apoptosis was analyzed by flow cytometry. The protein levels of p38, p-p38 and cleaved caspase-3 in the cells were detected by Western blot. DCDHF-DA was used to estemate the generation of reactive oxygen species (ROS) in the cells. RESULTS: The viability of PIGI cells decreased after exposed to H₂O₂ (P<0.05), and the half maximal inhibitory concentration of H₂O₂ was 0.7 mmol/L. Transfection with PDGFRα over-expression vector successfully induced high expression of PDGFRα at mRNA and protein levels in the PIGI cells, and increased the viability of the cells with H₂O₂ treatment (P<0.05). Over-expression of PDGFRα decreased the apoptotic rate of PIGI cells treated with H₂O₂ (P<0.05), and the level of ROS in the cells (P<0.05). The protein levels of cleaved caspase-3 and p-p38 were also decreased (P<0.05). CONCLUSION: PDGFRα inhibits the apoptosis of melanocytes induced by H₂O₂, partially reverses the growth inhibition of melanocytes by H₂O₂, and decreases the ROS level. The mechanism may be related to regulating the protein levels of p-p38 and cleaved caspase-3 in the cells.     

Effects of the grub extract on apoptosis of MCF-7 human breast cancer cell line

AIM: To investigate the apoptotic pathway of MCF-7 breast cancer induced by the grub extract in vitro.METHODS: MTT assay was used to determine the effect of the grub extract on proliferation of MCF-7 human breast cancer cell line and cell toxicity. Morphological changes of the apoptosis in cancer cells were observed by HE staining through invert microscope, light microscope, AO/EB double fluorescent staining under fluorescent microscope. FCM was used to assay the change of apoptotic rate. The expression of Bcl-2, Fas, caspase-9, caspase-3 in apoptotic pathway was detected with immunocytochemical method before and after exposure to the grub extract, and the effect of that on apoptotic pathway was explored.RESULTS: (1) The MTT test showed that the growth of MCF-7 human breast cancer cell line was significantly inhibited by the grub extract in dose and time dependent manners. The inhibitory rate in exposure group was significantly different from that in control group (P<0.01). (2) Morphological changes of apoptosis including nuclear condensation, fragment and apoptosis body formation were observed by invert microscope. (3) The MCF-7 human breast cancer cells in experimental group by HE staining showed nuclear condensation and blue-black, cytoplasm slight red, nuclear chromatin condensation and fragment shape, apoptosis body formations. (4) Apoptosis in the experimental group was observed by AO/EB double fluorescent staining under fluorescent microscope. (5) FCM assay indicated that apoptotic rate increased significantly in time dependent manner in experimental group. (6) The expression of Bcl-2 was down-regulated, while that of Fas, caspase-3, caspase-9 was up-regulated, compared with control group (P<0.01).CONCLUSION: (1) The proliferation of MCF-7 human breast cancer cell line can be inhibited significantly by the grub extract in vitro. (2)The mechanism of effect of the grub extract on MCF-7 human breast cancer cell line might be mediated by down-regulation of Bcl-2 and up-regulation of Fas, caspase-3, caspase-9. This type of apoptosis starting and performing is through death receptor pathway and mitochondrial pathway.     

Effects of oleanolic acid on apoptosis and cell cycle of HL-60 cells in vitro

AIM: To study the mechanism of oleanolic acid induced apoptosis and its influence on cell cycle in HL-60 cells in vitro. METHODS: The HL-60 cells were treated with different concentrations of oleanolic acid and then cultured for 12 h, 24 h, 48 h and 72 h, respectively. MTT assay was used to evaluate the inhibitory effect of oleanolic acid on HL-60 cells in vitro. The argarose gel electrophoresis was used to detect the chromatin DNA fragmentation. FACS was used to analyze the cell cycle of HL-60 cells. Western blotting was used to detect the activation of caspase-3 which has been confirmed the last execution of apoptosis pathway. RESULTS: MTT assay showed that oleanolic acid dramatically inhibited the growth of HL-60 cells in vitro, more than 50% HL-60 cells were inhibited when the cells were treated with 80 μmol/L oleanolic acid for 48 h; the apparent DNA ladder was detected after exposure of HL-60 cells to oleanolic acid for 48 h. FACS analysis showed that cell cycle of HL-60 cells was arrested in G₁ phase, the inhibition ratio of HL-60 cells achieved 63.24% and 67.90% after treated with oleanolic acid for 48 h and 72 h correspondingly. Western blotting detected the activation of caspase-3 after exposure of HL-60 cells to 80 μmol/L oleanolic acid for 48 h. CONCLUSION: These results suggest that oleanolic acid induces apoptosis and the cell cycle of HL-60 cells is arrested in G₁ phase.     

Effects of amlodipine on apoptosis of vascular endothelial cells induced by oxyeterols

AIM:To investigate the apoptosis of endothelial cells (EC) induced by oxysterols and to examine the effect of amlodipine on the apoptosis induced by oxysterols.METHODS:Light microscope, electron microscope, DNA agarose gel electrophoresis and flow cytometry were used to detect the apoptosis of EC.RESULTS:The characteristic morphological features of apoptosis were observed under light and electron microscope; DNA electrophoresis showed"DNA Ladder"; Flow cytometry showed the sub-G1 peak, apoptotic rate is 32.25% and 23.04% in Triol-treated and 25-OH-treated groups, respectively. While treated EC with amlodipine at the same time, the apoptotic rate decreased significantly.CONCLUSION:Both Triol and 25-OH can induce apoptosis of EC, which can be inhibited by amlodipine.     

Effect of lentiviral vector of microRNA-9-1 on differentiation of mouse bone marrow mesenchymal stem cells into neurons

AIM: To investigate the role of microRNA-9 in inducing bone marrow mesenchymal stem cell(MSCs) differentiation into neurons.METHODS: The lentiviral vector of microRNA-9-1(microRNA-9-1-LV) was constructed and transfected into mouse MSCs. The cells were divided into non-transfected group, transfected group(transfected with microRNA-9-1-LV) and negative control group(transfected with FU-RNAi-NC-LV). MSCs were treated with β-mercaptoethanol(β-ME) as an inducer for triggering the cells to differentiate into neurons. The fluorescence expressed by transfected MSCs were observed under inverted fluorescence microscope. The mRNA expression of microtublin-associated protein 2(MAP-2) was detected by RT-PCR. The expression of neuron-specific markers,neuron-specific enolase(NSE), MAP-2 and glial fibrillary acidic protein(GFAP), were measured by immunocytochemical method. The viability of MSCs was determined by MTT method. RESULTS: The results of PCR confirmed successful construction of mouse microRNA-9-1-LV. The virus titer was 1×10¹² TU/L(TU, transduction unit). The best transfection efficiency(up to 91.3%±4.2%) and survival rate appeared when multiply of infection(MOI)was 20 and on 4th day. β-ME induced MSCs to differentiate into neurons and the best efficiency of the induction was observed in transfected group. The expression levels of NSE and MAP-2 in transfected cells were higher than those in the cells of other group(P<0.05).CONCLUSION: MicroRNA-9-1-LV has high transfection efficiency in mouse MSCs. Higher differentiation rate from mouse MSCs to neurons is induced by β-ME after the cells are transfected with microRNA-9-1-LV.