肝细胞生长因子减轻皮质神经元的缺氧/复氧损伤

Hepatocyte growth factor attenuates hypoxia/reoxygenation injury in cortical neurons

目的研究肝细胞生长因子(HGF)对缺氧/复氧诱导大鼠皮质神经元凋亡的保护。方法分离培养SD大鼠皮质神经元,经HGF(15、30和60μg/L)预处理后经缺氧/复氧诱导凋亡,用MTT比色法检测细胞存活率;用Hoechst33258染色法和流式细胞仪检测神经元的凋亡;用比色法检测细胞乳酸脱氢酶(LDH)和caspase-3活性变化。结果与正常对照组相比,缺氧/复氧组神经元的细胞存活率显著下降,细胞凋亡率和caspase-3活性升高(均P<0.05);而HGF预处理12 h可显著逆转缺氧/复氧所致的细胞存活率降低、凋亡率增加、LDH活性上升、caspase-3活性升高的改变(均P<0.05),且这些效应与HGF剂量正相关。此外,HGF的抗凋亡效应可被PI3K/Akt通路抑制剂LY294002阻断。结论HGF减轻缺氧/复氧所诱导的神经元凋亡可能与其激活神经元的PI3K/Akt信号通路、减少caspase-3表达有关。

Objective To investigate the protective effect of hepatocyte growth factor（HGF） on cultured Sprague-Dawley rat cortical neurons injured through hypoxia/reoxygenation.Methods Primary cultured cerebral cortical neurons were isolated from newborn rats.Neurons were pre-incubated with different concentrations（15,30 and 60 μg/L） of HGF.The cell viability was detected by MTT.Apoptosis was measured by Hoechst 33258 staining and flow cytometer.Lactate dehydrogenase（LDH） and caspase-3 activity were determined by colorimetry.Results Compared with normal group,hypoxia/reoxygenation treatment significantly decreased cell viability,increased LDH activity and the percentage of apoptotic cells.Pretreatment of HGF for 12 h could remarkably reverse the decrease of cell viability and the increase of apoptosis rate in neurons induced by hypoxia/reoxygenation treatment.HGF pre-treatment also attenuated the activity of LDH and caspase-3 in a dose-dependent manner.The effects of HGF could be inhibited by a special PI3K/Akt pathway inhibitor,LY294002.Conclusion HGF could attenuate rat cortical neuron injury induced by hypoxia/reoxygenation.The neuroprotective effect of HGF may be related to activating PI3K/Akt pathway,and further suppressing the expression of caspase-3.