Effects of miR⁃145⁃3p on mitophagy in MPP + Ⅳinduced PD cell model by regulating the CaMkkβ/AMPK/CREB pathway / 安徽医科大学学报

ABSTRACT

Objective @# To investigate the effect and mechanism of miR⁃145 ⁃3p on mitophagy in 1 ⁃methyl⁃4 ⁃pheny⁃lpyridiniumion ( MPP + ) Ⅳinduced Parkinson ′ s disease ( PD) cell model . @*Methods @# Human neuroblastoma cells SH⁃SY5Y) were divided into control group , model group , mimics group , calmodulin⁃dependent protein kinase kinaseβ (CaMkkβ) inhibitor ( STO⁃609) group , mimics + STO⁃609 group , cyclic adenosine monophosphate response element⁃binding protein (CREB) inhibitor (KG⁃501) group , mimics + KG⁃501 group and STO⁃609 + KG⁃501 group . Cell apoptosis was detected by flow cytometry , autophagosome structure was observed by transmission electron microscopy , and apoptosis , autophagy and CaMkkβ/adenylate activated protein kinase ( AMPK) /CREB pathway related protein expression were detected by Western blot . @*Results @#Compared with control group , the apoptosis rate , Bcl⁃2 ⁃associated X protein (Bax) , cysteine proteinase⁃3 (Caspase⁃3) and microtubule⁃associated protein light chain 3 ⁃I (LC3 ⁃ Ⅰ ) protein expression levels in model group increased (P < 0. 01) , and the autophagosome structure decreased . The protein levels of B cell lymphoma⁃2 (Bcl⁃2) , autophagy gene (Beclin⁃1) , microtubule⁃associated protein light chain 3 ⁃ Ⅱ ( LC3 ⁃ Ⅱ ) , phosphorylated calmodulin⁃dependent protein kinase kinaseβ(p⁃CaMkkβ) , phosphorylated cadenylate activated protein kinase ( p⁃AMPK) , and phosphorylated cyclic adenosine monophosphate response element⁃binding protein ( p⁃CREB) decreased ( P < 0. 01) . Compared with model group , the apoptosis rate , Bax , Caspase⁃3 and LC3 ⁃ Ⅰ protein expression levels in mimics group decreased (P <0. 05 ) , and the autophagosome structure increased . The protein levels of Bcl⁃2 , Beclin⁃1 , LC3 ⁃ Ⅱ , p ⁃CaMkkβ , p ⁃AMPK , p ⁃CREB increased (P < 0. 05) . The trend of STO⁃609 group and KG⁃501 group was the same and opposite to mimics group . Compared with mimics group , the apoptosis rate , Bax , Caspase⁃3 and LC3 ⁃ Ⅰ protein expression levels in the mimics + STO⁃609 group and the mimics + KG⁃501 group increased (P < 0. 01) , and the autophagosome structure decreased . The protein levels of Bcl⁃2 , Beclin⁃1 , LC3 ⁃ Ⅱ , p ⁃CaMkkβ , p ⁃AMPK , p ⁃CREB protein levels decreased (P < 0. 01) . Compared with STO⁃609 group , the apoptosis rate , Bax , Caspase⁃3 and LC3 ⁃ Ⅰ pro⁃tein expression levels of STO⁃609 + KG⁃501 group increased ( P < 0. 01) , and the autophagosome structure decreased . The protein levels of Bcl⁃2 , Beclin⁃1 , LC3 ⁃ Ⅱ , p ⁃CaMkkβ , p ⁃AMPK and p ⁃CREB decreased ( P <0. 05) . @*Conclusion @# miR⁃145 ⁃3p can inhibit the apoptosis of MPP + Ⅳinduced PD cell model and promote mitophagy , and its mechanism may be related to the activation of the CaMkkβ/AMPK/CREB pathway .