Anti-inflammatory activity of nicotine isolated from Brassica oleracea in rheumatoid arthritis

Objectives: Rheumatoid arthritis (RA) is an autoimmune disease, associated with chronic inflammation of synoviocytes. Tumor necrosis factor α (TNF-α) plays a crucial role in the pathogenesis of RA through pro-inflammatory cytokines. Nicotine, an alkaloid used as herbal medicine, often worked as an anti-inflammatory agent. In the present study, we tried to uncover the anti-inflammatory impact of nicotine against RA. Materials and methods: Nicotine was isolated from Brassica oleracea, purified by high profile/phase liquid chromatography (HPLC). In-silico docking was carried out using bioinformatics tools SwissADME (absorption, distribution, metabolism and excretion), PASS, and Drug-induced Gene Expression Profile (DIGEP)-Pred to determine drug likeliness of nicotine. The in-vitro study was performed in TNFα-induced SW982 synoviocytes by qPCR. mRNA expression of pro-inflammatory cytokines (TNF, IL6, IL1β) and proteins (TRAF2, P50, P65) were analyzed followed by validation of P65 (RELA), pP65, IkBα by Western blot analysis. Results: Nicotine compound was extracted from Brassica oleracea and purified by HPLC method (R(t) values at 2.67 min). The physicochemical, pharmacokinetic properties and drug-likeliness of nicotine were studied by in-silico analysis. In-vitro studies revealed that nicotine lowers the expression of inflammatory cytokines (TNF, IL6, IL1β) and proteins (TNF receptor-associated factor 2 (TRAF2), P50, P65) at 1 µg/ml in TNFα-induced SW982 cells. Conclusion: Nicotine from natural sources (Brassica oleracea) has been found to be an effective anti- inflammatory compound at a low dosage; thus, identifying the role of nicotine present in the natural sources as a therapeutic option for RA, may be recommended as remedial drug instead of synthetic drug.