APP5肽类似物165对链脲佐菌素损伤SH-SY5Y细胞的保护作用

The protective role of APP5 peptide analogue 165 in the human neuroblastoma SH-SY5Y cells damaged by streptozotocin

目的探讨体外APP5肽类似物165(下称P165)对链脲佐菌素(STZ)损伤SH-SY5Y细胞的保护作用。方法STZ0.8mmol/L作用于SH-SY5Y细胞的损伤模型。通过测定噻唑蓝(MTT)代谢率、乳酸脱氢酸(LDH)漏出率,瑞氏染色观察细胞形态,Western blot检测相关蛋白,观察P165的保护作用。结果与正常对照组细胞的MTT代谢率(1.00±0.01)和LDH漏出率(201.56±47.54)比较,STZ损伤组细胞MTT代谢率降低(0.84±0.01),LDH漏出率升高(317.83±76.95),差异有统计学意义(P<0.05),细胞胞体面积缩小,胰岛素信号通路相关蛋白IRS-1、PI3K表达减少;P16530μmol/L组细胞MTT代谢率升高(0.91±0.01),LDH漏出率降低(228.53±35.65),细胞形态恢复正常,胰岛素信号通路相关蛋白IRS-1、PI3K表达恢复正常。结论体外STZ与SH-SY5Y细胞共孵育,可能影响胰岛素/胰岛素受体信号转导系统对细胞的促生长作用,而P165可能通过激活该信号通路逆转这种损伤,可作为一种神经营养因子起到保护作用。

Objective To investigate the protection of the growth of human neuroblastoma SH- SY5Y cells against streptozotocin damage by APP5 peptide analogue 165 （P165）. Methods MTT metabolic rate and LDH leakage rate were measured. Cell morphology was observed by Wright stain. The proteins associated with insulin signaling passage way such as IRS-1 ,PI3K were assayed by Western blot. Results Streptozotocin prevents the growth of human neuroblastoma SH-SY5Y cells with MTT metabolic rate decreasing （0. 84 ± 0. 01 ）, while LDH leakage rate was increasing （317. 83± 76.95 ） at STZ 0.8 mmol/L group as compared with normal control group （MTT metabolic rate： 1.00 ±0.01; LDH leakage rate ：201.56± 47.54）. Obvious cell morphological changes were observed by Wright stain. The P165 could protect the cells and promote the rehabilitation of these abnormalities along with MTT metabolic rate increasing（0. 91±0.01）and LDH leakage rate decreasing（228.53±35.65）. Conclusions STZ may damage the human neuroblastoma SH-SYSY cells by inhibitting the insulin signaling pathway which is essential for cells growth. The P165 could protect the SH-SY5Y cells as a neurotrophic factor.