BACKGROUND Cardiovascular diseases are the major cause of mortality worldwide.Regeneration of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart tis...BACKGROUND Cardiovascular diseases are the major cause of mortality worldwide.Regeneration of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart tissue.Cardiac tissue engineering using biomaterial scaffolds combined with stem cells and bioactive molecules could be a highly promising approach for cardiac repair.Use of biomaterials can provide suitable microenvironment to the cells and can solve cell engraftment problems associated with cell transplantation alone.Mesenchymal stem cells(MSCs)are potential candidates in cardiac tissue engineering because of their multilineage differentiation potential and ease of isolation.Use of DNA methyl transferase inhibitor,such as zebularine,in combination with three-dimensional(3D)scaffold can promote efficient MSC differentiation into cardiac lineage,as epigenetic modifications play a fundamental role in determining cell fate and lineage specific gene expression.AIM To investigate the role of collagen scaffold and zebularine in the differentiation of rat bone marrow(BM)-MSCs and their subsequent in vivo effects.METHODS MSCs were isolated from rat BM and characterized morphologically,immunophenotypically and by multilineage differentiation potential.MSCs were seeded in collagen scaffold and treated with 3μmol/L zebularine in three different ways.Cytotoxicity analysis was done and cardiac differentiation was analyzed at the gene and protein levels.Treated and untreated MSC-seeded scaffolds were transplanted in the rat myocardial infarction(MI)model and cardiac function was assessed by echocardiography.Cell tracking was performed by DiI dye labeling,while regeneration and neovascularization were evaluated by histological and immunohistochemical analysis,respectively.RESULTS MSCs were successfully isolated and seeded in collagen scaffold.Cytotoxicity analysis revealed that zebularine was not cytotoxic in any of the treatment groups.Cardiac differentiation analysis showed more pronounced results in the type 3 treatment group which was subsequently chosen for the transplantation in the in vivo MI model.Significant improvement in cardiac function was observed in the zebularine treated MSC-seeded scaffold group as compared to the MI control.Histological analysis also showed reduction in fibrotic scar,improvement in left ventricular wall thickness and preservation of ventricular remodeling in the zebularine treated MSC-seeded scaffold group.Immunohistochemical analysis revealed significant expression of cardiac proteins in DiI labeled transplanted cells and a significant increase in the number of blood vessels in the zebularine treated MSC-seeded collagen scaffold transplanted group.CONCLUSION Combination of 3D collagen scaffold and zebularine treatment enhances cardiac differentiation potential of MSCs,improves cell engraftment at the infarcted region,reduces infarct size and improves cardiac function.展开更多
INTRODUCTIONLiver fibrosis is mainly characterized by theexcessive synthesis and decreased degradation ofextracellular matrix(ECM),especially the synthesisand deposition of collagen.Almost all kinds of cellsin the liv...INTRODUCTIONLiver fibrosis is mainly characterized by theexcessive synthesis and decreased degradation ofextracellular matrix(ECM),especially the synthesisand deposition of collagen.Almost all kinds of cellsin the liver have participated in the production ofcollagen.The most important ones are hepaticstellate cells(HSC)and hepatocytes.We展开更多
Objective: To study the injury effect and molecular mechanism of high glucose on myocardial cells. Methods: Myocardial cells H9 c2 were cultured and divided into the control group treated with DMEM containing 5.5 mmol...Objective: To study the injury effect and molecular mechanism of high glucose on myocardial cells. Methods: Myocardial cells H9 c2 were cultured and divided into the control group treated with DMEM containing 5.5 mmol/L glucose, the high glucose group treated with DMEM containing 35 mmol/L glucose, and the N-acetylcysteine(NAC) group pre-treated with 1000μmol/L NAC and treated with DMEM containing 1000 μmol/L NAC and 35 mmol/L glucose.The production of ROS and the expression of mitochondria pathway apoptosis molecules in cells as well as the contents of collagen and collagen metabolism molecules were measured.Results: After 8 h, 16 h and 24 h of treatment, ROS RFU as well as Bax, CytC, Caspase-3 and Caspase-9 protein expression in cells and Col-I, Col-Ⅲ, PINP and PⅢNP protein levels in culture medium of high glucose group were higher than those of control group, Bcl-2 protein expression were lower than those of control group, but CTX-Ⅰ protein levels in culture medium were not significantly different from those of control group; after 24 h of treatment, Bax, CytC,Caspase-3 and Caspase-9 protein expression in cells as well as Col-Ⅰ, Col-Ⅲ, PINP and PIIINP protein levels in culture medium of NAC group were lower than those of high glucose group whereas Bcl-2 protein expression was higher than that of high glucose group. Conclusions:High glucose can induce myocardial cell apoptosis, increase collagen synthesis and accelerate interstitial fibrosis by increasing the production of reactive oxygen species.展开更多
目的探讨自体骨髓间质干细胞移植对梗死心肌基本结构及心肌收缩力的影响。方法贵州香猪24只,随机分为对照组和实验组,每组12只。抽取骨髓3 mL,按照W ak itan i方法培养出骨髓间质干细胞,经5-氮胞苷诱导后,5-溴脱氧尿苷标记备用。开胸结...目的探讨自体骨髓间质干细胞移植对梗死心肌基本结构及心肌收缩力的影响。方法贵州香猪24只,随机分为对照组和实验组,每组12只。抽取骨髓3 mL,按照W ak itan i方法培养出骨髓间质干细胞,经5-氮胞苷诱导后,5-溴脱氧尿苷标记备用。开胸结扎左冠状动脉前降支后,实验组第三代自体骨髓间质干细胞分别注射至结扎的左冠状动脉前降支和远端多点注入急性心肌梗死区域;对照组以同样方法注射DMEM。术后3、6周取标本,组织切片染色,观察组织基本结构;体外药物刺激离体肌条,检测心肌收缩情况。结果VG染色显示实验组胶原纤维融合较少,组织结构排列基本处于有序状态。实验组心肌收缩力明显高于对照组(P<0.001),且随时间推移恢复程度增加(P<0.05)。结论自体骨髓间质干细胞梗死心肌移植可以增加心肌细胞的收缩力,调节组织内胶原纤维的含量和组成,防止心室重构,从而起到对心肌基本结构的保护作用。展开更多
文摘BACKGROUND Cardiovascular diseases are the major cause of mortality worldwide.Regeneration of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart tissue.Cardiac tissue engineering using biomaterial scaffolds combined with stem cells and bioactive molecules could be a highly promising approach for cardiac repair.Use of biomaterials can provide suitable microenvironment to the cells and can solve cell engraftment problems associated with cell transplantation alone.Mesenchymal stem cells(MSCs)are potential candidates in cardiac tissue engineering because of their multilineage differentiation potential and ease of isolation.Use of DNA methyl transferase inhibitor,such as zebularine,in combination with three-dimensional(3D)scaffold can promote efficient MSC differentiation into cardiac lineage,as epigenetic modifications play a fundamental role in determining cell fate and lineage specific gene expression.AIM To investigate the role of collagen scaffold and zebularine in the differentiation of rat bone marrow(BM)-MSCs and their subsequent in vivo effects.METHODS MSCs were isolated from rat BM and characterized morphologically,immunophenotypically and by multilineage differentiation potential.MSCs were seeded in collagen scaffold and treated with 3μmol/L zebularine in three different ways.Cytotoxicity analysis was done and cardiac differentiation was analyzed at the gene and protein levels.Treated and untreated MSC-seeded scaffolds were transplanted in the rat myocardial infarction(MI)model and cardiac function was assessed by echocardiography.Cell tracking was performed by DiI dye labeling,while regeneration and neovascularization were evaluated by histological and immunohistochemical analysis,respectively.RESULTS MSCs were successfully isolated and seeded in collagen scaffold.Cytotoxicity analysis revealed that zebularine was not cytotoxic in any of the treatment groups.Cardiac differentiation analysis showed more pronounced results in the type 3 treatment group which was subsequently chosen for the transplantation in the in vivo MI model.Significant improvement in cardiac function was observed in the zebularine treated MSC-seeded scaffold group as compared to the MI control.Histological analysis also showed reduction in fibrotic scar,improvement in left ventricular wall thickness and preservation of ventricular remodeling in the zebularine treated MSC-seeded scaffold group.Immunohistochemical analysis revealed significant expression of cardiac proteins in DiI labeled transplanted cells and a significant increase in the number of blood vessels in the zebularine treated MSC-seeded collagen scaffold transplanted group.CONCLUSION Combination of 3D collagen scaffold and zebularine treatment enhances cardiac differentiation potential of MSCs,improves cell engraftment at the infarcted region,reduces infarct size and improves cardiac function.
基金National Natural Science Foundation of China,No.39670906
文摘INTRODUCTIONLiver fibrosis is mainly characterized by theexcessive synthesis and decreased degradation ofextracellular matrix(ECM),especially the synthesisand deposition of collagen.Almost all kinds of cellsin the liver have participated in the production ofcollagen.The most important ones are hepaticstellate cells(HSC)and hepatocytes.We
基金supported by Research Projects of Wuhan Health Bureau(No.wx12c35)
文摘Objective: To study the injury effect and molecular mechanism of high glucose on myocardial cells. Methods: Myocardial cells H9 c2 were cultured and divided into the control group treated with DMEM containing 5.5 mmol/L glucose, the high glucose group treated with DMEM containing 35 mmol/L glucose, and the N-acetylcysteine(NAC) group pre-treated with 1000μmol/L NAC and treated with DMEM containing 1000 μmol/L NAC and 35 mmol/L glucose.The production of ROS and the expression of mitochondria pathway apoptosis molecules in cells as well as the contents of collagen and collagen metabolism molecules were measured.Results: After 8 h, 16 h and 24 h of treatment, ROS RFU as well as Bax, CytC, Caspase-3 and Caspase-9 protein expression in cells and Col-I, Col-Ⅲ, PINP and PⅢNP protein levels in culture medium of high glucose group were higher than those of control group, Bcl-2 protein expression were lower than those of control group, but CTX-Ⅰ protein levels in culture medium were not significantly different from those of control group; after 24 h of treatment, Bax, CytC,Caspase-3 and Caspase-9 protein expression in cells as well as Col-Ⅰ, Col-Ⅲ, PINP and PIIINP protein levels in culture medium of NAC group were lower than those of high glucose group whereas Bcl-2 protein expression was higher than that of high glucose group. Conclusions:High glucose can induce myocardial cell apoptosis, increase collagen synthesis and accelerate interstitial fibrosis by increasing the production of reactive oxygen species.
文摘目的探讨自体骨髓间质干细胞移植对梗死心肌基本结构及心肌收缩力的影响。方法贵州香猪24只,随机分为对照组和实验组,每组12只。抽取骨髓3 mL,按照W ak itan i方法培养出骨髓间质干细胞,经5-氮胞苷诱导后,5-溴脱氧尿苷标记备用。开胸结扎左冠状动脉前降支后,实验组第三代自体骨髓间质干细胞分别注射至结扎的左冠状动脉前降支和远端多点注入急性心肌梗死区域;对照组以同样方法注射DMEM。术后3、6周取标本,组织切片染色,观察组织基本结构;体外药物刺激离体肌条,检测心肌收缩情况。结果VG染色显示实验组胶原纤维融合较少,组织结构排列基本处于有序状态。实验组心肌收缩力明显高于对照组(P<0.001),且随时间推移恢复程度增加(P<0.05)。结论自体骨髓间质干细胞梗死心肌移植可以增加心肌细胞的收缩力,调节组织内胶原纤维的含量和组成,防止心室重构,从而起到对心肌基本结构的保护作用。
