Cytokine and prostaglandin production by monocytes of volunteers and rheumatoid arthritis patients treated with dietary supplements of blackcurrant seed oil.

In this study, dietary supplements of blackcurrant seed oil (BCO) rich in the n-6 polyunsaturated fatty acid (PUFA) gamma-linolenic acid were fed to both RA patients and healthy volunteers with sunflower seed oil being fed to control subjects. A significant improvement in morning stiffness was noted in the RA patients receiving BCO. Monocytes were isolated from all subjects and cultured in the presence of lipopolysaccharide. It was observed that the production from the cultured monocytes of the cytokines IL-1 beta, TNF alpha and IL-6 as well as the prostaglandin PGE2 was markedly altered in those subjects given BCO. The results suggest that the numerous beneficial effects of PUFAs in inflammatory diseases such as RA may be due to a reduction in the secretion of the inflammatory cytokines IL-1 beta and TNF-alpha via redirection of eicosanoid metabolism although the possibility cannot be excluded that the PUFAs may be altering cytokine release directly through an effect on monocyte membranes.