E2对MPP^+诱导SH-SY5Y细胞损伤保护作用及G15的阻断效应

PROTECTIVE EFFECT OF 17β-ESTRADIOL AGAINST SH-SY5Y CELL INJURY INDUCED BY 1-METHYL-4-PHENYLPYRIDINIUM AND THE BLOCKING EFFECT OF G15

目的探讨17β-雌二醇(E2)对1-甲基-4-苯基吡啶离子(MPP^+)诱导的SH-SY5Y细胞损伤的保护作用及G蛋白耦联雌激素受体(GPER)特异性阻断剂G15的阻断效应。方法应用MPP^+损伤人神经母细胞瘤SH-SY5Y细胞,制备帕金森病细胞模型。实验分为对照组、MPP^+组、MPP^++E2组、MPP^++E2+G15组。MPP^++E2组先应用E2(10nmol/L)预保护24h,再给予MPP^+(1mmol/L)共同作用24h;MPP^++E2+G15组先应用G15(1μmol/L)处理1h,再给予E2和MPP^+处理。应用MTT法检测细胞存活率,免疫印迹法检测Bax和Bcl-2蛋白的表达。结果 MPP^+可明显降低细胞的存活率(F=8.424,q=6.511,P<0.01),此作用可以被E2预保护所拮抗(q=4.718,P<0.05)。MPP^+可明显降低Bcl-2蛋白的表达(F=12.92,q=8.674,P<0.01),增加Bax蛋白的表达(F=13.13,q=7.714,P<0.01);E2预保护可明显逆转上述改变(q=4.645、7.578,P<0.05)。GPER特异性阻断剂G15对E2的神经保护作用有阻断趋势,但差异无统计学意义(P>0.05)。结论 E2能够对抗神经毒MPP^+对SH-SY5Y细胞的损伤,但在本模型系统中GPER可能不是介导雌激素神经保护作用的主要靶点。

Objective To investigate the protective effect of 17β-estradiol（E2）against SH-SY5 Ycell injury induced by 1-methyl-4-phenylpyridinium（MPP^＋）and the blocking effect of G protein-coupled estrogen receptor（GPER）antagonist G15.Methods Human neuroblastoma SH-SY5 Ycells were injured by MPP^＋to establish a cell model of Parkinson disease.The cells were divided into control group,MPP^＋group,MPP^＋＋E2 group,and MPP^＋＋E2＋G15 group.The cells in the MPP^＋＋E2 group were pretreated with E2（10 nmol/L）for 24 hours for protection and then treated with MPP^＋（1 mmol/L）for 24 hours,and those in the MPP^＋＋E2＋G15 group were treated with G15（1μmol/L）for 1 hour,followed by E2 and MPP^＋.MTT assay was used to measure cell viability,and Western blotting was used to measure the protein expression of Bax and Bcl-2. Results Compared with the control group,the MPP^＋group had a significant reduction in cell viability（F=8.424,q=6.511,P〈0.01）,and this effect was antagonized by E2 pretreatment（q=4.718,P〈0.05）.MPP^＋significantly reduced the protein expression of Bcl-2（F=12.92,q=8.674,P〈0.01）and increased the protein expression of Bax（F=13.13,q=7.714,P〈0.01）,while E2 pretreatment significantly reversed these changes（q=4.645 and 7.578,P〈0.05）.The neuroprotective effect of E2 was slightly but not significantly blocked by the GPER antagonist G15（P〈0.05）. Conclusion E2 can protect SH-SY5 Ycells against the injury induced by the neurotoxicant MPP^＋,but in this cell model system,GPER may not be the main target for the neuroprotective effect of E2.