Stanniocalcin-1对大鼠神经元缺血性损伤的保护作用

Protective Effect of Stanniocalcin-1 on Neuron of Rats after Ischemic Injury

目的:探讨Stanniocalcin-1(STC-1)对神经元缺血性损伤的保护作用及其可能的作用机制。方法:分离培养大鼠大脑皮质神经元,缺氧/缺糖处理构建神经元缺血性损伤模型。构建过表达STC-1的重组逆转录病毒并转染细胞;UCP2 siRNA转染抑制解偶联蛋白2(UCP2)表达;实时荧光定量PCR(q RT-PCR)和Western Blotting检测STC-1和UCP2的m RNA及蛋白表达;乳酸脱氢酶(LDH)方法测定LDH漏出量和噻唑兰(MTT)方法测定细胞生长活力;检测Caspase-3活性。结果:成功建立缺氧/缺糖神经细胞损伤模型。过表达STC-1,缺氧/缺糖损伤的神经元LDH漏出量减少(P<0.01),细胞生长活力显著升高(P<0.05),Caspase-3活性降低(P<0.05),且Bcl-2蛋白表达量增多(P<0.01);另外STC-1下游分子UCP2的m RNA和蛋白表达量显著增加(P<0.01);另外,在过表达STC-1且抑制UCP2的情况下,细胞生长活力明显下降(P<0.05)。结论:STC-1对缺血性损伤的神经细胞起保护作用,可能通过调控UCP2来保护神经细胞。

Objective： To investigate the protective effect of Stanniocalcin-1 （STC-1） on neurons after ischemic injury. Methods： The neurons were isolated from rat cortex and cultured. The cultured neurons were then sub- jected to anoxic and glucose-deprived injury. The retroviral of STC-1 overexpression was constructed and trans- letted into the neurons, which were also transfected with uncoupling protein 2 （UCP2） siRNA to inhibit the UCP2 expression. The relative mRNA and protein expression levels of STC-I and UCP2 were detected by qRT-PCR and Western Blotting. The amount of LDH leakage was determined by LDH method, and cell growth and viability was determined by MTT method. The activity of Caspase-3 was detected. Results： The model of nerve cells with anoxic and OGD was constructed successfully. The up-regulation of STC-1 was verified, the amount of LDH leakage （P〈0.01） and Caspase-3 activity were significantly reduced（P〈0.05） whereas cell growth activity （P〈0.05） and the protein expression of Bcl-2 were significantly increased with STC-1 overexpression （P〈 0.01）. Moreover, the expression of UCP2, a downstream gene of STC-1, was also increased by STC-1 overex- pression （P〈0.01）. The cell growth activity was obviously reduced with STC-1 overexpression and UCP2 inhibi- tion （/1〈0.05）. Conclusion： STC-1 may protect neurons against ischemic injury through regulating UCP2.