Anisomeles indica (L.) Kuntze leaf essential oil ameliorates LPS-induced inflammation in RAW 264.7 cells: An integrated approach of network pharmacology and experimental validation

Abstract

Anisomeles indica (L.) Kuntze (Lamiaceae), commonly called catmint, is an essential oil-bearing herb used in traditional systems of medicine against rheumatism, convulsions, inflammatory skin disorders, and epilepsy. However, the efficacy and mechanism of action of its essential oil against inflammatory conditions remain elusive. The current study aims at the chemical characterization of the essential oil of A. indica leaves (AILEO) and understanding the mechanism of its anti-inflammatory effects by an integrated approach of network pharmacology and in vitro assays. GC–MS analysis of AILEO revealed a total of 30 constituents representing 94.19 % of the total oil. The majority of the chemical groups include diterpene hydrocarbons with abietatriene (58.13 %) and abietadiene (7.18 %) as the major constituents. Out of 30 compounds, 20 passed the ADME screening and were considered as active constituents. A total of 524 compound targets, 409 anti-inflammation targets, and 88 compound-disease intersecting targets were obtained. Multi-level network analysis revealed that the pharmacological mechanisms of alleviation of inflammation by AILEO are due to its interaction with five core inflammatory targets such as PI3K, AKT1, MEK1, ERK1, and RXRA involved in the PI3K-AKT signaling pathway. AILEO did not exhibit any cytotoxic effect on RAW 264.7 cells, but it significantly inhibited nitric oxide (NO) production and reduced the levels of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) in vitro assays. Further, AILEO enhanced the expression levels of endogenous antioxidant enzymes (CAT, SOD, GPx, and GSH) in comparison to the LPS-induced group. RT-qPCR analysis revealed that AILEO modulated the level of mRNA expression of all five core targets associated with the PI3K-AKT signaling pathway, which further supported the findings of network pharmacology. This study provides valuable insights into the intricate mechanisms by which AILEO exerts anti-inflammatory action indicating its pharmacological potential as a promising candidate for the treatment of disorders linked with inflammation.