Beneficial interaction of pycnogenol with indomethacin in rats.

Cyclooxygenase 2 (COX-2) is responsible for the therapeutic effects of indomethacin, while inhibition of the COX-1 enzyme and oxidative stress are responsible for its gastro-toxic effects. It has been reported that pycnogenol increases the expression of COX-1, suppresses the expression rate of COX-2 and oxidative stress. Our aim in this study is to investigate the antiinflammatory activities of indomethacin, pycnogenol, and their combination (PI) in rats and to examine their effects on stomach tissue. In the study, anti-inflammatory activity was investigated in carrageenan-induced inflammatory paw edema in albino Wistar male rats. Effects on stomach tissue were performed by applying the previous method. PI, indomethacin and pycnogenol were the best suppressors of carrageenan inflammation and oxidative stress in paw tissue, respectively. While the groups with the lowest COX-1 activity in paw tissue were IC, PIC and PC, respectively, PIC, IC and PC were the ones that best inhibited the increase in COX-2 activity. Pycnogenol inhibited the increase of malondialdehyde, the decrease of total glutathione and COX-1 in the stomach, and significantly suppressed the formation of indomethacin ulcers. Our experimental results showed that pycnogenol reduced the toxic effect of indomethacin on the stomach and increased anti-inflammatory activity. This beneficial interaction of pycnogenol and indomethacin suggests that PI will provide superior success in the treatment of inflammatory diseases.