梓醇对乳胞素诱导SH-SY5Y细胞损伤的保护作用

Protective effect of catalpol on lactacysin-induced injury in SH-SY5Y cells

目的探讨梓醇对蛋白酶体抑制剂乳胞素诱导的人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用及其可能机制。方法梓醇10μmol·L-1预处理SH-SY5Y细胞1 h后,加入乳胞素10μmol·L-1继续处理24 h。倒置显微镜下观察细胞形态的变化,MTT比色法检测细胞存活率,流式细胞仪检测细胞凋亡率,Hoechst33258染色观察细胞核形态的变化,酶联免疫吸附检测细胞内20S蛋白酶体含量。结果与正常对照组相比,梓醇10μmol·L-1对细胞存活率、形态和凋亡及20S蛋白酶体含量无显著差异;乳胞素10μmol·L-1组细胞存活率为(72.0±1.8)%,明显降低(P<0.05),细胞凋亡率为(64.7±2.6)%,明显增高(P<0.05)。Hoechst33258染色发现梓醇细胞核形态改变,出现凋亡小体;细胞内20S蛋白酶体含量降低60%,差异具有统计学意义(P<0.05)。与乳胞素10μmol·L-1组相比,梓醇10μmol·L-1预处理组细胞存活率(87.9±2.2)%明显增高(P<0.05),细胞凋亡率为(51.4±1.5)%,明显降低(P<0.05)。Hoechst33258染色发现,梓醇细胞核形态明显改善;细胞内20S蛋白酶体含量升高了1.9倍,差异具有统计学意义(P<0.05)。结论梓醇对乳胞素诱导的SH-SY5Y细胞损伤具有保护作用,其机制可能与梓醇提高SH-SY5Y细胞内20S蛋白酶体含量有关。

OBJECTIVE To investigate the protective effect of catalpol on lactacysin-induced injury in human neuroblastoma（SH-SY5Y） cells and to explore the potential mechanism.METHODS SH-SY5Y cells were pretreated with catalpol 10 μmol·L-1 for 1 h and then exposed to lactacytin 10 μmol·L-1 for 24 h.The cell morphous were observed under an inverted microscopy.Cell viability was detected by MTT assay.Cell nucleus changes were assessed by Hoechst33258 staining.The cell apoptosis rate was measured by flow cytometry using Annexin-Ⅴ and propidumiodide（PI）.The human 20S proteasome content was detected by enzyme-linked immunosorbent assay.RESULTSCompared with normal control group,catalpol 10 μmol·L-1 had no significant effect on cell survival,cell morphology,cell apoptosis,or the content of 20S proteasome.But in lactacystin 10 μmol·L-1 group,cell survival significantly decreased to（72.0±1.8）% while the apoptosis rate increased to（64.7±2.6） %（P0.05）.The cell morphology in lactacystin 10 μmol·L-1 group was changed and even apopototic bodies were observed.The content of 20S proteasome decreased 2.5 fold（P0.05）.Compared with lactacysin 10 μmol·L-1 group,the survival rate increased to（87.9±2.2）% and apoptosis rate decreased to（51.4±1.5）% in catalpol 10 μmol·L-1 group（P0.05）.Hoechst33258 staining showed the improvement in cell nucleus,and the content of 20S proteasome increased by 2.9 fold（P0.05）.CONCLUSION Catalpol has protective effect against lactacysitn-induced injury in SH-SY5Y cells,and the mechanism may be associated with the increase of the content of 20S proteasome in cells.