抑制PI3K/Akt/mTOR信号通路对MPP+ 处理的SH-SY5Y 细胞自噬、凋亡及PD特征蛋白表达的影响.

Objective To investigate effects of inhibiting phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/ mammalian target of rapamycin (mTOR) signaling pathway on autophagy, apoptosis, the expression of Parkinson's disease (PD) characteristic protein α-synuclein (α-syn) and tyrosine hydroxylase (TH) in SH-SY5Y cells treated with 1-methyl-4- phenylpyridine (MPP+ ). Methods SH-SY5Y cells were treated with MPP+, PI3K/Akt activator insulin-like growth factor-1 (IGF-1) and PI3K/Akt inhibitor LY294002. CCK-8 was performed to measure the cell viability. Flow cytometry was used to detect cell apoptosis rate. Acridine orange (AO) staining was used to detect autophagic vacuoles. Western blot assay was used to measure protein levels of α-syn, TH, p62, microtubule-associated protein 1 light chain 3B (LC3B), p-mTOR, mTOR, pPI3K, PI3K, p-Akt and Akt. Results MPP+ intervention significantly reduced the survival rate of SH-SY5Y cells in a dose-dependent manner (P＜0.05). The survival rate of SH-SY5Y cells decreased and the apoptosis rate increased after MPP+ and IGF-1 treatment (P＜0.05). The autophagic vacuoles in cells decreased, the ratio of LC3BⅡ/Ⅰ decreased, and the level of p62 protein increased (P＜0.05). The level of TH protein decreased and the level of α-syn protein increased (P＜ 0.05). The ratios of p-PI3K/PI3K, p-Akt/Akt and p-mTOR/mTOR were increased (P＜0.05). The effect of LY294002 on SH-SY5Y cells was opposite to that of MPP+ and IGF-1, and LY294002 was able to reverse the effect of MPP+ on SH-SY5Y cells to a certain extent (P＜0.05). Conclusion Inhibition of PI3K/Akt/mTOR signaling pathway has a protective effect on MPP+ -induced SH-SY5Y cytotoxicity, which provides a new theoretical basis for the treatment of PD. [ABSTRACT FROM AUTHOR]