Evaluation of the Mechanism of Action of Rosemary Volatile Oil in the Treatment of Alzheimer's Disease Using Gas Chromatography -mass Spectrometry Analysis and Network Pharmacology

Objective: This study aimed to investigate the active components and mechanism of action of rosemary volatile oil for treating Alzheimer's disease (AD) using network pharmacology. Methods: We obtained the constituents of the rosemary volatile oil by searching Chinese herbal systemic pharmacological databases and analytical platforms and constructed the constituent-target networks by predicting and screening the action targets of the rosemary volatile oil constituents using SwissTargetPrediction, metaTarFisher, and Pubchem. We obtained the AD-related targets using the Genecards, OMIM, and DisGeNET databases and constructed the protein-protein interaction networks (PPI) using the STRING database in Venny 2.1.0 graph to identify the cross-targets by screening the core-acting targets. Cytoscape 3.8.2 software was used to construct a componenttarget- pathway network to screen the potential active components of the rosemary volatile oil for the treatment of AD and predict the mechanism of action of the rosemary volatile oil for the treatment of AD in combination with existing pharmacological studies. We performed a gene ontology (GO) biological process and a Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of the targets of the rosemary volatile oil for the treatment of AD using R language and molecular docking using Discovery Studio 4.0 software to validate their biological activities. Results: A network constructed using gas chromatography-mass spectrometry (GC-MS) analysis identified 26 potentially active ingredients in the rosemary volatile oil. We retrieved a total of 10762 AD targets from Genecards and other databases. Our GO enrichment analysis yielded 39 entries (P < 0.05), including 14 entries for biological processes, five entries for cellular composition, and 20 entries for molecular function. A total of 14 entries (P < 0.05) were then enriched in the KEGG pathway that primarily involved the IL-17 signaling pathway and the AGE-RAGE pathway. Conclusion: The active components of rosemary volatile oil had good inhibition of the inflammatory response. This study provides a reference and guidance for the in-depth study on rosemary volatile oil for the treatment of AD.