Exogenous electrical stimulation plays an important role on endothelial cells and vessels. Study on the effect of electrical stimulation on endothelial cells might be helpful to regulate cell metabolism on a certain e...Exogenous electrical stimulation plays an important role on endothelial cells and vessels. Study on the effect of electrical stimulation on endothelial cells might be helpful to regulate cell metabolism on a certain extent, or provide new ideas for vascular tissue engineering. A bioreactor that can apply electrical stimulation was designed on the basis of parallel-plate chamber. To investigate the possible effect of electrical stimulation on human umbilical vein endothelial cells (HUVECs), the different levels and duration′s electrical stimulations were applied to HUVECs in culture. The cell morphology was observed by microscopy and the levels of endothelial nitric oxide synthase (eNOS) gene were measured by RT-PCR. Different levels and durations of electrical stimulation produce different effects on eNOS gene expression. The eNOS gene expressions of the experimental group cells under the voltage of 50 mV, 100 mV,150 mV and 200 mV were significantly lower than that of the control group after 3-hour electrical stimulation, while the eNOS gene levels of the experimental group cells in 6-hour electrical stimulation were higher than those of the control group under all tested voltages. After 12-hour stimulation, the eNOS gene levels of HUVECs decreased under 50 mV, and then gradually increased until 200 mV. The low voltage of 6-hour electrical stimulation is more appropriate for HUVECs growth.展开更多
Large conductance Ca^(2+)-activated K^+ (BK_(Ca)) channel exhibits a phenotype-dependent expression on vascular smooth muscle cells(VSMCs), which prefers to contractile phenotype. Meanwhile, shear stress definitely in...Large conductance Ca^(2+)-activated K^+ (BK_(Ca)) channel exhibits a phenotype-dependent expression on vascular smooth muscle cells(VSMCs), which prefers to contractile phenotype. Meanwhile, shear stress definitely influences VSMCs proliferation and contraction. Thereby, a hypothesis was raised, would shear stress change the BK_(Ca)expression and correlate with VSMC phenotype? In order to investigate it, VSMCs were exposed to shear stress in a parallel-plate flow chamber with 12 dynes/cm^2 for 12 h. Subsequently, the effect of shear stress on VSMC proliferation, BK_(Ca)channel expression and contractile phenotype marker, α-smooth muscle cell actin(α-SMA) and smooth muscle myosin heavy chain(SMMHC), was determined by immunofluorescence microscopy, flow cytometery as well as reverse transcriptionpolymerase chain reaction(RT-PCR), respectively. Data show that shear stress enhanced the expression of BK_(Ca)channel while inhibiting VSMC proliferation.Paralleled to those phenomena, the expression of both α-SMA and SM-MHC were decreased significantly. These results demonstrated that upregulation of BK_(Ca)channel was irrelevant to the maintenance VSMC of contractile phenotype under shear stress.This finding provides a new insight into understanding the correlation of BK_(Ca)channel and VSMC phenotype.展开更多
Differentiation of bone marrow mesenchymal stem cells (MSCs) into endothelial cells (EC) is characterized by the expression of specific endothelial marker genes. Mechanical stimulations play potential effects in EC or...Differentiation of bone marrow mesenchymal stem cells (MSCs) into endothelial cells (EC) is characterized by the expression of specific endothelial marker genes. Mechanical stimulations play potential effects in EC oriented differentiation of MSCs. However, molecular mechanisms of endothelial differentiation from MSCs have not been defined.Histone acetylations play important roles in regulating gene expression. Histone acetylation status is maintained by histone acetyltransferase (HAT) and histone deacetylases (HDACs). Our previous work described that VEGF and laminar shear stress (SS) work together in determining EC oriented differentiation of MSC. Trichostatin A (TSA) is one of the lustone deacetylase inhibitor. In this study, we found that both TSA and SS could induce EC oriented differentiation of MSCs. And TSA combined with SS showed more powerful influence on the EC oriented differentiation of MSCs.展开更多
The heart is regulated by excitation-contraction mechanism and electrical stimulation, so both cardiac tissues and myocytes in vivo are affected by the mechanical and electrical factors at the same time. The device th...The heart is regulated by excitation-contraction mechanism and electrical stimulation, so both cardiac tissues and myocytes in vivo are affected by the mechanical and electrical factors at the same time. The device that can supply both tensile stimulation and electrical stimulation was produced. Cardiomyocytes were isolated by trypsin and collagenase Ⅱ combined digestion. After 72 h's culture, different electrical stimulations(0.5 V/cm, 1 V/cm, 2 V/cm;1 Hz;2 ms;30 min) and mechanical stretching force(tensile 10%, 6 h) were used to stimulate cultured cardiomyocytes respectively. Then the combinative stimulation of mechanical and electrical stimulation with 0.5 V/cm was used to apply to cardiomyocytes simultaneously. After stimulation,Connexin-43(Cx-43) mRNA level was detected by RT-PCR. The stimulation by electrical pulse of 0.5 V/cm resulted in obvious enhancement of Cx-43 m RNA level compared to the control group and the Cx-43 mRNA levels at 0.5 V/cm were higher significantly than those under both 1.0 V/cm and 2.0 V/cm. After 10% of tensile stimulation for 6 h, expressions of Cx-43 mRNA were also significantly promoted. The combinative effect of mechanical and electrical stimulation on the expression of Cx-43 mRNA is higher than that under unique tensile stimulation or electrical stimulation,which is more beneficial to the development and connection of cardiomyocytes.展开更多
文摘Exogenous electrical stimulation plays an important role on endothelial cells and vessels. Study on the effect of electrical stimulation on endothelial cells might be helpful to regulate cell metabolism on a certain extent, or provide new ideas for vascular tissue engineering. A bioreactor that can apply electrical stimulation was designed on the basis of parallel-plate chamber. To investigate the possible effect of electrical stimulation on human umbilical vein endothelial cells (HUVECs), the different levels and duration′s electrical stimulations were applied to HUVECs in culture. The cell morphology was observed by microscopy and the levels of endothelial nitric oxide synthase (eNOS) gene were measured by RT-PCR. Different levels and durations of electrical stimulation produce different effects on eNOS gene expression. The eNOS gene expressions of the experimental group cells under the voltage of 50 mV, 100 mV,150 mV and 200 mV were significantly lower than that of the control group after 3-hour electrical stimulation, while the eNOS gene levels of the experimental group cells in 6-hour electrical stimulation were higher than those of the control group under all tested voltages. After 12-hour stimulation, the eNOS gene levels of HUVECs decreased under 50 mV, and then gradually increased until 200 mV. The low voltage of 6-hour electrical stimulation is more appropriate for HUVECs growth.
基金The National Natural Science Foundation of Chinagrant number:10972024,11120101001,10925208,and 10802006+3 种基金Doctoral Fund of Ministry of Education of Chinagrant number:0800061001National Basic Research Program of Chinagrant number:2011CB710901
文摘Large conductance Ca^(2+)-activated K^+ (BK_(Ca)) channel exhibits a phenotype-dependent expression on vascular smooth muscle cells(VSMCs), which prefers to contractile phenotype. Meanwhile, shear stress definitely influences VSMCs proliferation and contraction. Thereby, a hypothesis was raised, would shear stress change the BK_(Ca)expression and correlate with VSMC phenotype? In order to investigate it, VSMCs were exposed to shear stress in a parallel-plate flow chamber with 12 dynes/cm^2 for 12 h. Subsequently, the effect of shear stress on VSMC proliferation, BK_(Ca)channel expression and contractile phenotype marker, α-smooth muscle cell actin(α-SMA) and smooth muscle myosin heavy chain(SMMHC), was determined by immunofluorescence microscopy, flow cytometery as well as reverse transcriptionpolymerase chain reaction(RT-PCR), respectively. Data show that shear stress enhanced the expression of BK_(Ca)channel while inhibiting VSMC proliferation.Paralleled to those phenomena, the expression of both α-SMA and SM-MHC were decreased significantly. These results demonstrated that upregulation of BK_(Ca)channel was irrelevant to the maintenance VSMC of contractile phenotype under shear stress.This finding provides a new insight into understanding the correlation of BK_(Ca)channel and VSMC phenotype.
基金National Natural Science Foundation of Chinagrant number:10925208,11120101001,10802006 and 10972024+1 种基金NFundamental Research Funds for the Central Universitiesgrant number:YWF-10-02-065
文摘Differentiation of bone marrow mesenchymal stem cells (MSCs) into endothelial cells (EC) is characterized by the expression of specific endothelial marker genes. Mechanical stimulations play potential effects in EC oriented differentiation of MSCs. However, molecular mechanisms of endothelial differentiation from MSCs have not been defined.Histone acetylations play important roles in regulating gene expression. Histone acetylation status is maintained by histone acetyltransferase (HAT) and histone deacetylases (HDACs). Our previous work described that VEGF and laminar shear stress (SS) work together in determining EC oriented differentiation of MSC. Trichostatin A (TSA) is one of the lustone deacetylase inhibitor. In this study, we found that both TSA and SS could induce EC oriented differentiation of MSCs. And TSA combined with SS showed more powerful influence on the EC oriented differentiation of MSCs.
基金National Natural Science Foundation of Chinagrant number:10802006,10925208,11120101001 and 10972024
文摘The heart is regulated by excitation-contraction mechanism and electrical stimulation, so both cardiac tissues and myocytes in vivo are affected by the mechanical and electrical factors at the same time. The device that can supply both tensile stimulation and electrical stimulation was produced. Cardiomyocytes were isolated by trypsin and collagenase Ⅱ combined digestion. After 72 h's culture, different electrical stimulations(0.5 V/cm, 1 V/cm, 2 V/cm;1 Hz;2 ms;30 min) and mechanical stretching force(tensile 10%, 6 h) were used to stimulate cultured cardiomyocytes respectively. Then the combinative stimulation of mechanical and electrical stimulation with 0.5 V/cm was used to apply to cardiomyocytes simultaneously. After stimulation,Connexin-43(Cx-43) mRNA level was detected by RT-PCR. The stimulation by electrical pulse of 0.5 V/cm resulted in obvious enhancement of Cx-43 m RNA level compared to the control group and the Cx-43 mRNA levels at 0.5 V/cm were higher significantly than those under both 1.0 V/cm and 2.0 V/cm. After 10% of tensile stimulation for 6 h, expressions of Cx-43 mRNA were also significantly promoted. The combinative effect of mechanical and electrical stimulation on the expression of Cx-43 mRNA is higher than that under unique tensile stimulation or electrical stimulation,which is more beneficial to the development and connection of cardiomyocytes.