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

•LPS was used to induced inflammatory reaction in RAW264.7 macrophages.•Grape seed proanthocyanidins suppressed the mRNA level of inflammatory mediators.•Grape seed proanthocyanidins suppressed the secretion of inflammatory mediators.•GSPs treatment inhibited the nuclear factor-κB and MAPK 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-κB) 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-α (TNF-α), interleukin-1β (IL-1β) 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 IKKα/β and NF-κB 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-κB signal transduction pathways.