摘要
目的探讨丝裂原和应激激活蛋白激酶1(MSK-1)及cAMP反应元件结合蛋白(CREB)在低氧预适应(HPC)保护小鼠缺血脑组织中的作用。方法将健康成年雄性BALB/c小鼠随机分为4组:常氧假手术组(NS)、HPC假手术组(HS)、常氧缺血组(NI)和HPC缺血组(HI)。利用已建整体HPC和大脑中动脉阻塞(MCAO)小鼠模型,并结合神经行为学评价、氯化三苯基四氮唑(TTC)染色和蛋白印迹(Western blot)等技术,观察HPC对小鼠脑缺血损伤的影响,检测小鼠脑皮层不同缺血区域内MSK-1和CREB磷酸化水平和蛋白表达量的变化。结果 HPC可明显改善小鼠脑缺血后神经行为学表现,减小MCAO致脑缺血皮层梗死体积和水肿率;MCAO致小鼠脑局部皮层缺血后,其缺血核心区内MSK-1和CREB磷酸化水平明显下降(P<0.05);HPC可明显增加缺血半影区内MSK-1和CREB磷酸化水平(P<0.05),而MSK-1和CREB总蛋白表达量在缺血核心区和半影区内均无明显改变。结论 HPC可能通过提高缺血半影区内MSK-1及其底物CREB的磷酸化水平来降低小鼠缺血性脑损伤。
Objective To explore the role of mitogen-and stress-activated protein kinase 1(MSK-1) and cAMP response element binding protein(CREB) in hypoxic preconditioning(HPC)-induced neuroprotection against cerebral ischemic injuries.Methods Healthy male BALB/c mice were randomly divided into 4 groups as follows: normoxia sham(NS),HPC sham(HS),normoxia ischemia(HI) and HPC ischemia(HI).Using HPC and middle cerebral artery occlusion(MCAO)-induced focal cerebral ischemia mouse models,and the techniques of triphenyltetrazolium chloride(TTC) staining,neurological deficits evaluation and Western blot,we observed the neurological scores,brain infarct volume,the phosphorylation and protein expression level of MSK-1 and CREB in regions of ischemic cortex.Results HPC attenuated MCAO-induced neurological deficits,and decreased brain infarctvolume and edema ratio of mice.The phosphorylation level of MSK-1 and CREB decreased significantly(P0.05,n=4) in the ischemic core,while HPC could promote significantly(P0.05,n=4) both MSK-1 and CREB phosphorylation level in penumbra of MCAO-induced ischemic cortex.However,there was no significant change of total MSK-1 and CREB protein expressions in the ischemic regions of MCAO-treated HPC mice.Conclusion The increased MSK-1 and CREB phosphorylations in ischemic penumbra were involved in HPC-induced neuroprotection against cerebral ischemic injuries of mice.
出处
《基础医学与临床》
CSCD
北大核心
2010年第11期1143-1148,共6页
Basic and Clinical Medicine
基金
国家自然科学基金(30871219)
国家重点基础性研究项目(2006CB5041)
北京市教育委员会科技计划重点项目(KZ200810025012)
北京市属高等学校人才强教计划项目(京教人[2008]17号)
北京市新世纪百千万人才工程培养经费(08-016)
教育部高等学校博士点科研基金(20091107110001)