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
Previous studies have suggested that miR-324-3p is related to the pathophysiology of cerebral ischemia,but the mechanism underlying this relationship is unclea r.In this study,we found that miR-324-3p expression was d...Previous studies have suggested that miR-324-3p is related to the pathophysiology of cerebral ischemia,but the mechanism underlying this relationship is unclea r.In this study,we found that miR-324-3p expression was decreased in patients with acute ischemic stroke and in in vitro and in vivo models of ischemic stro ke.miR-324-3p agomir potentiated ischemic brain damage in rats subjected to middle cerebral artery occlusion,as indicated by increased infarct volumes and cell apoptosis rates and greater neurological deficits.In a PC12 cell oxygen-glucose deprivation/reoxygenation model,a miR-324-3 p mimic decreased cell viability and expression of the anti-apoptotic protein BCL2 and increased expression of the pro-apoptotic protein BAX and rates of cell apoptosis,whereas treatment with a miR-324-3p inhibitor had the opposite effects.Silencing miR-324-3p increased adenosine A1 receptor(A1R)expression thro ugh regulation of GATA binding protein 2(GATA2).These findings suggest that silencing miR-324-3p reduces ischemic brain damage via the GATA2/A1R axis.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funded by the National Natural Science Foundation of China,No.81803937(to YCM and QXD)Science and Technology Innovation Activity Plan for College Students of Zhejiang Province(Xinmiao Talent Plan),No.2020R413079(to AQZ)Wenzhou Science and Technology Plan Project,No.Y20210122(to QXD)。
文摘Previous studies have suggested that miR-324-3p is related to the pathophysiology of cerebral ischemia,but the mechanism underlying this relationship is unclea r.In this study,we found that miR-324-3p expression was decreased in patients with acute ischemic stroke and in in vitro and in vivo models of ischemic stro ke.miR-324-3p agomir potentiated ischemic brain damage in rats subjected to middle cerebral artery occlusion,as indicated by increased infarct volumes and cell apoptosis rates and greater neurological deficits.In a PC12 cell oxygen-glucose deprivation/reoxygenation model,a miR-324-3 p mimic decreased cell viability and expression of the anti-apoptotic protein BCL2 and increased expression of the pro-apoptotic protein BAX and rates of cell apoptosis,whereas treatment with a miR-324-3p inhibitor had the opposite effects.Silencing miR-324-3p increased adenosine A1 receptor(A1R)expression thro ugh regulation of GATA binding protein 2(GATA2).These findings suggest that silencing miR-324-3p reduces ischemic brain damage via the GATA2/A1R axis.