Grape seed proanthocyanidin extract protects against carrageenan-induced lung inflammation in mice through reduction of pro-inflammatory markers and chemokine expressions.

Proanthocyanidins are the most abundant phenolic compounds and have been reported to exert anti-inflammatory actions. The aim of this study was to investigate the effects of grape seed proanthocyanidin extract (GSPE) in a mouse model of carrageenan-induced pleurisy. Following the induction of pleurisy using λ-carrageenan (Cg, 1 %), GSPE (25, 50 and 100 mg/kg) was administered per-oral (p.o.), and the glucocorticoid-induced tumour necrosis factor receptor (GITR), IL-17A expressing cells and other markers, such as cytokines (Th1/Th2 and Th17), were studied. We evaluate the effects of GSPE on the mRNA expression of pro-inflammatory and anti-inflammatory mediators. The results illustrated that the cell numbers of IL-17A and GITR expressing cells and the cytokine levels in Th1/Th17 cells were markedly increased in the Cg-group, whereas the cytokines produced by Th2 cells were significantly decreased in the same group. Treatment with GSPE reversed these effects. Histological examinations revealed anti-inflammatory effects of GSPE.