MP联合BDNF转染对脊髓损伤细胞模型凋亡机制的作用

Effects of a combined therapy with methylprednisolone and brain-derived neurotrophic factor on mechanisms of apoptosis of cell model of spinal cord injury

目的研究甲基强的松龙(MP)联合腺病毒介导脑源性神经营养因子(BDNF)转染对脊髓损伤细胞模型凋亡发生中氧化应激的影响及其作用机制。方法通过大鼠脊髓神经元细胞(rn-dsc)建立脊髓损伤细胞模型,分析MP+BDNF转染对脊髓损伤细胞模型中乳酸脱氢酶(LDH)漏出量、丙二醛(MDA)含量的影响,以及超氧化物歧化酶(SOD)活性的变化,利用流式细胞仪和MTT法分析细胞的凋亡率和存活率,Western Blot法分析细胞中Caspase 3及活化Cleaved caspase 3的表达情况。结果通过细胞外液LDH漏出量、MDA含量及SOD活性分析证实MP联合BDNF转染能够降低氧化应激对细胞的损伤;流式细胞仪、MTT法及Western Blot检测结果证实MP联合BDNF转染能够增强损伤细胞的抗凋亡作用,但是其抗氧化能力与凋亡率并不完全一致。结论 MP联合BDNF转染能够增强脊髓损伤细胞模型的抗氧化能力,并可能通过抗氧化应激反应提高模型细胞的抗凋亡能力,但是MP与BDNF抗凋亡作用还存在其他途径的参与。

Objective To investigate the effects of a combined therapy with methylprednisolone （MP） and brain-derived neurotrophic factor （BDNF） on oxidative stress during the process of apoptosis of cell model of spinal cord injury and the underlying mechanisms. Methods A rat neuron-dorsal spinal cord （rn-dsc） model of spinal cord injury was established. The effects of the combined therapy on malondialdehyde （MDA） and lactate dehydrogenase （LDH） levels as well as superoxide dismutase （SOD） activity were investigated. Cell apoptosis rate and survival rate in each group were detected by flow cytometry and MTF assay. Procaspase 3 and activated Cleaved caspase 3 expression levels in the cell models were determined by Western blot analysis. Results MDA, LDH levels and SOD activity results showed that the combined therapy alleviated oxidative stress-induced cell injury. Flow cytometry, MTT assay and Western blot analysis showed that the combined therapy strengthened the anti-apoptotie effects of injured ceils. However, after subjected to the combined therapy, cellular anti- oxidative capacity was not completely consistent with its anti-apoptosis rate. Conclusion These findings suggest that the combined therapy with MP and BDNF can strength the anti-oxidative capacity of cell models of spinal cord injury and increase cellular anti-apoptotic capacity possibly via anti-oxidative stress. However, there may be other pathways by which MP and BDNF exhibit anti-apoptotic effects.