Comparative Anti-Inflammatory Evaluation of Lamiaceae Essential Oils and Mechanistic Insights into Mentha haplocalyx Essential Oil via Network Pharmacology and Molecular Dynamics

Abstract

Abstract: This study investigated the essential oils from six Lamiaceae plants (Ocimum basilicum, Mentha haplocalyx, Rosmarinus officinalis, Lavandula angustifolia, Salvia sclarea, and Pogostemon cablin) and analyzed their chemical composition using gas chromatography-mass spectrometry (GC-MS). Their anti-inflammatory potential was evaluated in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. The results demonstrated that all six essential oils exhibited anti-inflammatory activity, with Mentha haplocalyx essential oil (MHEO) showing the most potent effects. GC-MS analysis identified menthol (49.46 %), isomenthone (27.68 %), and isomenthol (4.06 %) as its primary constituents. Further experiments revealed that MHEO significantly attenuated LPS-induced cytotoxicity and suppressed the production of inflammatory mediators (tumor necrosis factor-α (TNF-α ), interleukin-6 (IL-6), interleukin-1β (IL-1β), and nitric oxide (NO)). Real-time quantitative PCR (RT-QPCR) confirmed its ability to downregulate TNF-α, IL-6, IL-1β, and inducible nitric oxide synthase (iNOS) mRNA expression. To elucidate the bioactive compounds and underlying mechanisms, network pharmacology was used to construct a "compound-target-pathway" network. Molecular docking and molecular dynamics (MD) simulations identified 3-carvomenthenone and pulegone as key anti-inflammatory constituents targeting NLRP3. These findings provide a theoretical basis for the development of MHEO-based anti-inflammatory agents.