OBJECTIVE To investigate the effect of neferine （NEF） on mitophagy in Parkinson’s disease （PD） cells by regulating the adenosine monophosphate-activated protein kinase （AMPK）/mammalian target of rapamycin （mTOR）/UNC-51-like kinase 1 （ULK1） signaling pathway， and explore the mechanism of this drug to improve PD. METHODS SH-SY5Y cells were treated with 100 μmol/L 1-methyl-4-phenylpyridinium ion （MPP+） for 24 h to construct a PD cell model. PD model cells were divided into model group （PD group）， NEF low-， medium- and high-concentration groups （NEF-L， NEF-M， NEF-H group， 2.5， 5.0， 10.0 μmol/L）， and high concentration of NEF+AMPK inhibitor group （NEF-H+Compound C group， 10.0 μmol/L NEF+50 μmol/L Compound C）. The cells treated without MPP+ and NEF were used as the control group. The ultrastructure of the cells in each group was observed； the amount of autophagosomes， survival rate， apoptosis rate， mitochondrial membrane potential， and the protein expressions of Caspase-3， microtubule-associated protein 1 light chain 3 （LC3） and Beclin-1， as well as the phosphorylation levels of mTOR， AMPK and ULK1 were detected. RESULTS Compared with PD group， the amount of autophagosomes in NEF-L， NEF-M and NEF-H groups was increased， and membrane potential was increased； survival rate， LC3- Ⅱ/LC3-Ⅰ， protein expression of Beclin-1， and protein phosphorylation levels of AMPK and ULK1 were significantly increased or up-regulated； the apoptotic rate， protein expressions of Caspase-3 and p62， and protein phosphorylation level of mTOR were significantly decreased or down-regulated， and the above improvements were in a dose-dependent manner （P＜0.05）. Compound C could significantly reverse the above improvement effect of high concentration of NEF （P＜0.05）. CONCLUSIONS NEF can promote mitophagy and inhibit apoptosis of PD model cells by up-regulating protein phosphorylation levels of AMPK and ULK1， and down-regulating protein phosphorylation level of mTOR， thus playing a protective role in nerve cells.

OBJECTIVE To investigate the effect of neferine （NEF） on mitophagy in Parkinson’s disease （PD） cells by regulating the adenosine monophosphate-activated protein kinase （AMPK）/mammalian target of rapamycin （mTOR）/UNC-51-like kinase 1 （ULK1） signaling pathway， and explore the mechanism of this drug to improve PD. METHODS SH-SY5Y cells were treated with 100 μmol/L 1-methyl-4-phenylpyridinium ion （MPP+） for 24 h to construct a PD cell model. PD model cells were divided into model group （PD group）， NEF low-， medium- and high-concentration groups （NEF-L， NEF-M， NEF-H group， 2.5， 5.0， 10.0 μmol/L）， and high concentration of NEF+AMPK inhibitor group （NEF-H+Compound C group， 10.0 μmol/L NEF+50 μmol/L Compound C）. The cells treated without MPP+ and NEF were used as the control group. The ultrastructure of the cells in each group was observed； the amount of autophagosomes， survival rate， apoptosis rate， mitochondrial membrane potential， and the protein expressions of Caspase-3， microtubule-associated protein 1 light chain 3 （LC3） and Beclin-1， as well as the phosphorylation levels of mTOR， AMPK and ULK1 were detected. RESULTS Compared with PD group， the amount of autophagosomes in NEF-L， NEF-M and NEF-H groups was increased， and membrane potential was increased； survival rate， LC3- Ⅱ/LC3-Ⅰ， protein expression of Beclin-1， and protein phosphorylation levels of AMPK and ULK1 were significantly increased or up-regulated； the apoptotic rate， protein expressions of Caspase-3 and p62， and protein phosphorylation level of mTOR were significantly decreased or down-regulated， and the above improvements were in a dose-dependent manner （P＜0.05）. Compound C could significantly reverse the above improvement effect of high concentration of NEF （P＜0.05）. CONCLUSIONS NEF can promote mitophagy and inhibit apoptosis of PD model cells by up-regulating protein phosphorylation levels of AMPK and ULK1， and down-regulating protein phosphorylation level of mTOR， thus playing a protective role in nerve cells.