Potential anti-inflammatory properties of crude alcoholic extract of Ocimum basilicum L. in human peripheral blood mononuclear cells

Ocimum basilicum L. (Lamiaceae) is a well-known perennial herb in Indian medicine used to treat various disorders like upper respiratory tract infections and wound healing. Primarily we investigated the anti-inflammatory activity of crude extracts of Ocimum basilicum using peripheral blood mononuclear cells (PBMC) of healthy individuals. Ocimum basilicum crude methanolic extract showed a good inhibitory effect on the proliferative response of PBMC in mitogenic lymphocyte proliferation assays. Furthermore, gene expression studies on lipopolysaccharide (LPS) induced production of proinflammatory cytokines like Tumor necrosis factor-a (TNF-alpha), Interleukin-1 beta (IL-1 beta) and IL-2 showed down regulation of the markers. It also suppressed the induction of inducible nitric oxide synthase (iNOS) and the subsequent production of nitric oxide (NO) in LPS-stimulated RAW 264.7 macrophages in a time-dependent manner. Our results showed that Ocimum basilicum crude methanolic extract inhibits the key proinflammatory cytokines and mediators, which accounts for its anti-inflammatory effect.