5β-Hydroxypalisadin B isolated from red alga Laurencia snackeyi attenuates inflammatory response in lipopolysaccharide-stimulated RAW 264.7 macrophages

In this study, four compounds isolated from the red alga Laurencia snackeyi were evaluated for their potential anti-inflammatory effect in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. These compounds were tested for their inhibitory effects on nitric oxide (NO) production in LPS-stimulated RAW 264.7 cells. Since 5 beta-hydroxypalisadin B showed the best activity it was further tested for the production of prostaglandin-E-2 (PGE(2)), expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), the release of pro-inflammatory cytokines tumor necrotic factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and interleukin-6 (IL-6). 5 beta-Hydroxypalisadin B significantly reduced the PGE(2) release and suppressed the iNOS and COX-2 expression in LPS-stimulated RAW 264.7 cells. It also significantly reduced the release of pro-inflammatory cytokines TNF-alpha, IL-1 beta, and IL-6. These findings provide the first evidence of anti-inflammatory potential of 5 beta-hydroxypalisadin B isolated from the red alga L. snackeyi and hence, it could be exploited as an active ingredient in pharmaceutical, nutraceutical and functional food applications.