Picroside II Protects SH-SY5Y Cells From Autophagy and Apoptosis Following Oxygen Glucose Deprivation/Reoxygen Injury by Inhibiting JNK Signal Pathway.

To explore the neuroprotective effect of picroside (Picr) II on C-Jun NH2-terminal kinase (JNK) signal pathway after oxygen glucose deprivation/reoxygen (OGD/R) in SH-SY5Y cells. In vitro, SH-SY5Y cells were used to establish the OGD/R model, which was divided into the control group, model group, Picr group, and SP600125 (SP) group. Cellular viability was measured by CCK8. Cytotoxicity was assessed with LDH assay kit. Ad-GFP-mRFP-LC3 was used to monitor autophagosome and autolysosome. Apoptoic cells were detected by Annexin V-FITC/PI apoptosis detection kit. The expressions of phospho-JNK and phospho-c-Jun were determined by western blot (WB) and immunofluorescence. The expressions of phospho-MKK4, phospho-Bcl-2, Bax, Beclin-1, and LC3 I/II were determined by WB. In the control group, only limited apoptosis and autophagy was observed, and the expression of associated proteins was very low. After OGD/R, the cellular viability of SH-SY5Y cells was reduced, whereas the cytotoxicity, apoptosis, and autophagy were increased, accompanied with an increase of phospho-MKK4, phospho-JNK, phospho-c-Jun, phospho-Bcl-2, LC3 II, Beclin-1, and Bax. During the reoxygen, treatment with Picr II or SP600125 could strengthen the cellular viability of SH-SY5Y cells, but repress the cytotoxicity, apoptosis, autophagy, and the expressions of associated protein. OGD/R could induce apoptosis and autophagy of SH-SY5Y cells by activating JNK signal pathway. Picr II could protect SH-SY5Y cells from autophagy and apoptosis following OGD/R by inhibiting JNK signal pathway. Anat Rec, 302:2245-2254, 2019.