Objective To investigate the protective effects of hydrogen peroxide preconditioning （HPP） on the pheochromocytoma （PC12） cells treated with 1-methyl-4-phenylpyridinium （MPP^＋） and to explore the potential mech...Objective To investigate the protective effects of hydrogen peroxide preconditioning （HPP） on the pheochromocytoma （PC12） cells treated with 1-methyl-4-phenylpyridinium （MPP^＋） and to explore the potential mechanisms. Methods The viability and apoptosis of PC 12 cells were determinded by 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide （MTT） assay and 4′,6′-diamidino-2-phenylindole （DAPI） staining, respectively. The expressions of 14-3-3 protein and phospholylated p38 mitogen-activated protein kinase （MAPK） were determined by Western blot. Enzyme-linked immunosorbent assay （ELISA） was used to measure the activity of extracellular signal-regulated protein kinase 1/2 （ERK1/2）. Results The cell viability decreased and the number of apoptotic cells increased dramatically in MPP^＋ group compared with that in Control group. HPP induced a significant increase in cell viability and a marked decrease in population of apoptotic cells of the MPP^＋- treated PC 12 cells, accompanied with up-regulation of 14-3-3 protein and increase of ERK 1/2 and p38 MAPK activities. The 14-3-3 protein expression was positively correlated with the phosphorylation of ERK1/2. Furthermore, inhibition of the ERK1/2 with PD98059 abolished the 14-3-3 protein up-regulation in PC 12 cells induced by HPP. Conclusion HPP protects PC 12 cells against MPP＋ toxicity by up-regulating 14-3-3 protein expression through the ERK1/2 and p38 MAPK signaling pathways.展开更多
Objective:Cardiac remodeling is a common pathological change in various cardiovascular diseases and can ultimately result in heart failure.Thus,there is an urgent need for more effective strategies to aid in cardiac p...Objective:Cardiac remodeling is a common pathological change in various cardiovascular diseases and can ultimately result in heart failure.Thus,there is an urgent need for more effective strategies to aid in cardiac protection.Our previous work found that sphingosine-1-phosphate(S1P)could ameliorate cardiac hypertrophy.In this study,we aimed to investigate whether S1P could prevent cardiac fibrosis and the associated mechanisms in cardiac remodeling.Methods:Eight-week-old male C57BL/6 mice were randomly divided into a sham,transverse aortic constriction(TAC)or a TAC+S1P treatment group.Results:We found that S1P treatment improved cardiac function in TAC mice and that the cardiac fibrosis ratio in the TAC+S1P group was significantly lower and was accompanied by a decrease inα-smooth muscle actin(α-SMA)and collagen type I(COL I)expression compared with the TAC group.We also found that one of the key S1P enzymes,sphingosine kinase 2(SphK2),which was mainly distributed in cytoblasts,was downregulated in the cardiac remodeling case and recovered after S1P treatment in vivo and in vitro.In addition,our in vitro results showed that S1P treatment activated extracellular regulated protein kinases(ERK)phosphorylation mainly through the S1P receptor 2(S1PR2)and spurred p-ERK transposition from the cytoplasm to cytoblast in H9c2 cells exposed to phenylephrine.Conclusion:These findings suggest that SphK2 and the S1PR2/ERK pathway may participate in the anti-remodeling effect of S1P on the heart.This work therefore uncovers a novel potential therapy for the prevention of cardiac remodeling.展开更多
目的:探讨染料木黄酮(Genistein,Gen)与5氟尿嘧啶(5-fluorouracil,5-FU)诱导人肝癌M H C C97-L细胞周期阻滞与细胞外调节蛋白激酶(extracellular regulated protein kinasesERK)1/2信号通路的关系.方法:MTS法检测细胞增殖;流式细胞术检...目的:探讨染料木黄酮(Genistein,Gen)与5氟尿嘧啶(5-fluorouracil,5-FU)诱导人肝癌M H C C97-L细胞周期阻滞与细胞外调节蛋白激酶(extracellular regulated protein kinasesERK)1/2信号通路的关系.方法:MTS法检测细胞增殖;流式细胞术检测细胞周期;Western blot检测总ERK1/2和磷酸化ERK1/2蛋白表达.结果:Gen与5-FU单用及联用均能抑制肝癌MHCC97-L细胞增殖;Gen诱导细胞S期阻滞少量抑制ERK1/2磷酸化,ERK1/2抑制剂可促进Gen对MHCC97-L细胞的生长抑制作用,而对S期阻滞无明显影响;5-FU单用和二者联用组均阻滞S期细胞,并显著激活ERK1/2磷酸化ERK1/2抑制剂可促进两组药物对MHCC97-L细胞的生长抑制和诱导S期阻滞作用.结论:Gen与5-FU单用及联用均可通过阻滞细胞周期来发挥抗肝癌细胞增殖的作用;抑制ERK1/2通路可抵抗Gen诱导的肝癌细胞S期阻滞,而促进5-FU单用和二者联用组诱导肝癌细胞S期阻滞.展开更多
目的观察北五味子多糖(polysaccharide of Schisandra chinensis,SCP)对血管紧张素Ⅱ(AngiotensinⅡ,AngⅡ)诱导的心肌成纤维细胞(CFb)增殖作用,并探讨其作用机制.方法以培养的新生Wistar大鼠乳鼠CFb为实验模型,实验分为对照组、模型组...目的观察北五味子多糖(polysaccharide of Schisandra chinensis,SCP)对血管紧张素Ⅱ(AngiotensinⅡ,AngⅡ)诱导的心肌成纤维细胞(CFb)增殖作用,并探讨其作用机制.方法以培养的新生Wistar大鼠乳鼠CFb为实验模型,实验分为对照组、模型组、3个药物剂量组.采用胰酶消化、差速贴壁法培养CFb;四氮唑盐(MTT)比色法检测CFb增殖;羟脯氨酸(Hyp)法测定胶原含量;分光光度计测定CFb中超氧化物歧化酶(SOD)活力、丙二醛(MDA)水平;硝酸还原酶法和分光光度法分别测定不同干预条件下CFb培养液中一氧化氮合酶(NOS)活性及一氧化氮(NO)水平;免疫组化技术检测CFb中细胞外调节蛋白激酶(ERK1/2)蛋白表达.结果SCP能够显著抑制AngⅡ诱导的CFb增殖(P<0.05或P<0.01),降低Hyp含量,提高SOD活力,降低MDA水平(P<0.05,P<0.01),提高NOS活性及NO水平(P<0.05,P<0.01),减低ERK1/2蛋白表达(P<0.05,P<0.01).结论SCP可通过抑制ERK1/2信号通路提高NOS活性,并升高NO水平,增强抗AngⅡ诱导的CFb增殖能力.展开更多
基金the National Natural Science Foundation of China (No. 30570627)
文摘Objective To investigate the protective effects of hydrogen peroxide preconditioning （HPP） on the pheochromocytoma （PC12） cells treated with 1-methyl-4-phenylpyridinium （MPP^＋） and to explore the potential mechanisms. Methods The viability and apoptosis of PC 12 cells were determinded by 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide （MTT） assay and 4′,6′-diamidino-2-phenylindole （DAPI） staining, respectively. The expressions of 14-3-3 protein and phospholylated p38 mitogen-activated protein kinase （MAPK） were determined by Western blot. Enzyme-linked immunosorbent assay （ELISA） was used to measure the activity of extracellular signal-regulated protein kinase 1/2 （ERK1/2）. Results The cell viability decreased and the number of apoptotic cells increased dramatically in MPP^＋ group compared with that in Control group. HPP induced a significant increase in cell viability and a marked decrease in population of apoptotic cells of the MPP^＋- treated PC 12 cells, accompanied with up-regulation of 14-3-3 protein and increase of ERK 1/2 and p38 MAPK activities. The 14-3-3 protein expression was positively correlated with the phosphorylation of ERK1/2. Furthermore, inhibition of the ERK1/2 with PD98059 abolished the 14-3-3 protein up-regulation in PC 12 cells induced by HPP. Conclusion HPP protects PC 12 cells against MPP＋ toxicity by up-regulating 14-3-3 protein expression through the ERK1/2 and p38 MAPK signaling pathways.
基金supported by the National Natural Science Foundation of China(No.81873505).
文摘Objective:Cardiac remodeling is a common pathological change in various cardiovascular diseases and can ultimately result in heart failure.Thus,there is an urgent need for more effective strategies to aid in cardiac protection.Our previous work found that sphingosine-1-phosphate(S1P)could ameliorate cardiac hypertrophy.In this study,we aimed to investigate whether S1P could prevent cardiac fibrosis and the associated mechanisms in cardiac remodeling.Methods:Eight-week-old male C57BL/6 mice were randomly divided into a sham,transverse aortic constriction(TAC)or a TAC+S1P treatment group.Results:We found that S1P treatment improved cardiac function in TAC mice and that the cardiac fibrosis ratio in the TAC+S1P group was significantly lower and was accompanied by a decrease inα-smooth muscle actin(α-SMA)and collagen type I(COL I)expression compared with the TAC group.We also found that one of the key S1P enzymes,sphingosine kinase 2(SphK2),which was mainly distributed in cytoblasts,was downregulated in the cardiac remodeling case and recovered after S1P treatment in vivo and in vitro.In addition,our in vitro results showed that S1P treatment activated extracellular regulated protein kinases(ERK)phosphorylation mainly through the S1P receptor 2(S1PR2)and spurred p-ERK transposition from the cytoplasm to cytoblast in H9c2 cells exposed to phenylephrine.Conclusion:These findings suggest that SphK2 and the S1PR2/ERK pathway may participate in the anti-remodeling effect of S1P on the heart.This work therefore uncovers a novel potential therapy for the prevention of cardiac remodeling.
文摘目的:探讨染料木黄酮(Genistein,Gen)与5氟尿嘧啶(5-fluorouracil,5-FU)诱导人肝癌M H C C97-L细胞周期阻滞与细胞外调节蛋白激酶(extracellular regulated protein kinasesERK)1/2信号通路的关系.方法:MTS法检测细胞增殖;流式细胞术检测细胞周期;Western blot检测总ERK1/2和磷酸化ERK1/2蛋白表达.结果:Gen与5-FU单用及联用均能抑制肝癌MHCC97-L细胞增殖;Gen诱导细胞S期阻滞少量抑制ERK1/2磷酸化,ERK1/2抑制剂可促进Gen对MHCC97-L细胞的生长抑制作用,而对S期阻滞无明显影响;5-FU单用和二者联用组均阻滞S期细胞,并显著激活ERK1/2磷酸化ERK1/2抑制剂可促进两组药物对MHCC97-L细胞的生长抑制和诱导S期阻滞作用.结论:Gen与5-FU单用及联用均可通过阻滞细胞周期来发挥抗肝癌细胞增殖的作用;抑制ERK1/2通路可抵抗Gen诱导的肝癌细胞S期阻滞,而促进5-FU单用和二者联用组诱导肝癌细胞S期阻滞.
文摘目的观察北五味子多糖(polysaccharide of Schisandra chinensis,SCP)对血管紧张素Ⅱ(AngiotensinⅡ,AngⅡ)诱导的心肌成纤维细胞(CFb)增殖作用,并探讨其作用机制.方法以培养的新生Wistar大鼠乳鼠CFb为实验模型,实验分为对照组、模型组、3个药物剂量组.采用胰酶消化、差速贴壁法培养CFb;四氮唑盐(MTT)比色法检测CFb增殖;羟脯氨酸(Hyp)法测定胶原含量;分光光度计测定CFb中超氧化物歧化酶(SOD)活力、丙二醛(MDA)水平;硝酸还原酶法和分光光度法分别测定不同干预条件下CFb培养液中一氧化氮合酶(NOS)活性及一氧化氮(NO)水平;免疫组化技术检测CFb中细胞外调节蛋白激酶(ERK1/2)蛋白表达.结果SCP能够显著抑制AngⅡ诱导的CFb增殖(P<0.05或P<0.01),降低Hyp含量,提高SOD活力,降低MDA水平(P<0.05,P<0.01),提高NOS活性及NO水平(P<0.05,P<0.01),减低ERK1/2蛋白表达(P<0.05,P<0.01).结论SCP可通过抑制ERK1/2信号通路提高NOS活性,并升高NO水平,增强抗AngⅡ诱导的CFb增殖能力.
