
c-Jun氨基末端激酶介导的FOXO3a核转位在缺氧缺血性脑损伤新生大鼠神经元凋亡中的作用
李德渊, 伍金林, 罗黎力, 乔莉娜, 刘忠强, 卢国艳, 王杨
中国当代儿科杂志 ›› 2017, Vol. 19 ›› Issue (4) : 458-462.
c-Jun氨基末端激酶介导的FOXO3a核转位在缺氧缺血性脑损伤新生大鼠神经元凋亡中的作用
Role of c-Jun N-terminal kinase-mediated FOXO3a nuclear translocation in neuronal apoptosis in neonatal rats with hypoxic-ischemic brain damage
目的 探讨抑制c-Jun氨基末端激酶(JNK)/核转录因子FOXO3a信号通路对缺氧缺血性脑损伤(HIBD)新生大鼠神经元凋亡的保护作用机制。方法 将64只7日龄Sprague-Dawley大鼠随机分为假手术组、缺氧缺血(HI)组、二甲基亚砜(DMSO)溶剂组和JNK特异性抑制剂AS601245干预组(JNK抑制剂组)。各组分别在建模后24 h处死动物取大脑皮层,应用Western blot法定量检测JNK、p-JNK、FOXO3a、胞核FOXO3a、胞浆FOXO3a,以及促凋亡蛋白Bim及CC3的表达水平;应用TUNEL染色法检测神经细胞凋亡情况。结果 与假手术组相比,HI后24 h,p-JNK蛋白水平增高(P < 0.01);胞核FOXO3a蛋白水平增高,胞浆FOXO3a蛋白水平降低(P < 0.01);Bim及CC3表达水平增高(P < 0.01)。与HI组及DMSO溶剂组相比,JNK抑制剂组p-JNK蛋白水平降低(P < 0.01);胞核FOXO3a蛋白水平降低,胞浆FOXO3a蛋白水平增高(P < 0.01);Bim及CC3表达水平降低(P < 0.01)。JNK抑制剂组的TUNEL染色阳性细胞表达较HI组及DMSO溶剂组减少(P < 0.01)。结论 新生大鼠HIBD时,JNK发生磷酸化,活性增高;抑制JNK活性可抑制FOXO3a核转位,下调促凋亡蛋白Bim及CC3表达,减少神经细胞凋亡。
Objective To explore the mechanisms of neuroprotective effects of c-Jun N-terminal kinase (JNK)/FOXO3a transcription factor signaling pathway inhibition on hypoxic-ischemic neuronal apoptosis in neonatal rats with hypoxic-ischemic brain damage (HIBD). Methods Sixty-four 7-day-old Sprague-Dawley rats were divided into four groups:hypoxia-ischemia (HI), sham-operated, JNK specific inhibitor AS601245-treated, and DMSO vehicle. Rats' cerebral cortexes were collected at 24 hours after HI. Western blot was used to detect the protein expression of JNK, p-JNK, FOXO3a, nuclear and cytoplasmic FOXO3a, Bim, and CC3. TUNEL staining was used to detect the apoptotic cells. Results Compared with the sham-operated group, p-JNK protein increased (P < 0.01), nuclear protein of FOXO3a increased (P < 0.01), cytoplasmic protein decreased (P < 0.01), and pro-apoptotic proteins Bim and CC3 increased 24 hours after HI (P < 0.01). Compared with the HI and DMSO vehicle groups, p-JNK protein was reduced (P < 0.01), nuclear protein of FOXO3a was also reduced (P < 0.01), cytoplasmic protein increased (P < 0.01), and Bim and CC3 proteins decreased (P < 0.01) in the AS601245-treated group 24 hours after HI. TUNEL positive cells were reduced in the AS601245-treated rats compared with the HI and DMSO vehicle groups 24 hours after HI (P < 0.01). Conclusions JNK activity increases in the neonatal rat brain with HI damage. JNK activity inhibition can inhibit FOXO3a translocation from cytoplasm to nucleus and downregulate the levels of pro-apoptotic proteins Bim and CC3, leading to the reduction of neuronal apoptosis.
c-Jun氨基末端激酶 / FOXO3a / 缺氧缺血 / 凋亡 / 神经元 / 新生大鼠
c-Jun N-terminal kinase / FOXO3a / Hypoxia-ischemia / Apoptosis / Neuron / Neonatal rats
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国家自然科学基金(81000262);四川省卫生和计划生育委员会科研课题(16PJ240);四川省卫生和计划生育委员会资助项目(140045)。