OBJECTIVE To explore the mechanism of perillyl alcohol(PA) in delaying intervertebral disc degeneration(IDD) through network pharmacology, and validate its mechanism by molecular docking and molecular biology experiments.

METHODS The targets of PA were obtained from TCMSP, GeneCards and Swiss Target Prediction database. GeneCards and OMIM were used to obtain IDD-related targets, and the common targets of PA and IDD were obtained from the Venny 2.1.0 website. String database and Cytoscape software were used to construct the protein-protein interaction(PPI) network. DAVID and bioinformatics website were used for GO and KEGG analysis. AutoDock Vina and PyMOL were used for molecular docking verification of the core targets of PA and IDD. The network pharmacological prediction results were verified by quantitative real-time PCR(qRT-PCR), cellular immunofluorescence and reactive oxygen species detection.

RESULTS  A total of 213 PA targets and 2286 IDD targets were screened in this study, and 61 intersection targets of PA and IDD were obtained. PPI network analysis showed that 14 key targets of PA to delay IDD were AKT1, EGF, TP53, EGFR, etc. GO enrichment analysis involved the positive regulation of protein phosphorylation, positive regulation of programmed cell death, cyclin, serine/threonine kinase regulation, etc. KEGG enrichment analysis showed that PA delayed IDD involving JAK-STAT, ErbB, HIF-1 and other signaling pathways. Molecular docking results showed that PA had strong affinity and relatively stable binding conformation with the core targets such as ALB, EGFR and NOTCH1. Compared with the IL-1β group, the expression levels of MMP-1, MMP-13, ADAMTS4 and ADAMTS5 mRNA in the IL-1β+PA treatment group were decreased, ACAN was up-regulated, HIF-1α and NOTCH1 in the IL-1β+PA group were up-regulated, too. The difference was statistically significant.

CONCLUSION PA might act on NOTCH1, EGFR, ALB3 and other core targets to delay the progression of IDD through HIF-1α/NOTCH1 signaling pathway.