Grape-seed proanthocyanidins inhibit the lipopolysaccharide-induced inflammatory mediator expression in RAW264.7 macrophages by suppressing MAPK and NF-kappa b signal pathways

Grape-seed proanthocyanidins (GSPs) have been shown to function as an anti-oxidant and anti-inflammatory agent with little toxicity in vivo and in vitro. However, little is known about their anti-inflammatory properties and mechanisms of action. The specific focus being its effects on the MAP kinases and nuclear factor-kappaB (NF-kappa B) signal transduction pathways in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. GSPs extract has been found to suppress the mRNA expression of pro-inflammatory cytokines like tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta) and inflammatory molecule of cyclooxygenase-2 (COX-2) while mRNA level of IL-10 was greatly promoted. Furthermore, GSPs extract inhibited the expression of phosphorylated ERK, JNK and P38, as well as phosphorylated IKK alpha/beta and NF-kappa B p65 subunit. In conclusion, our results show that GSPs extract showed its anti-inflammatory and immunomodulatory properties by suppressing the activation of MAP kinases and NF-kappa B signal transduction pathways. (C) 2015 Elsevier B.V. All rights reserved.