The isoprostane 8-epi-PGF2α is a valuable indicator of oxidative injury in human heart valves

To date, little information is available concerning oxidative injury in human cardiac valves. Therefore, we sought to investigate whether the isoprostane, 8-epi-PGF2α, a novel oxidative stress marker, is localized in aortic and pulmonary valves derived from explanted hearts of patients suffering from idiopathic dilative cardiomyopathy (IDC). By using semiquantitative immunohistochemistry, we demonstrated that 8-epi-PGF2α is localized in both valves with pulmonary valves accumulating more of this isoprostane compared to aortic valves (36.69±12.04% vs. 31.54±11.49%, P<.05). These results were confirmed by a radioimmunoassay (RIA) analysis showing a similar, but not significant, difference between the two valves (288.50±72.18 pg/mg protein in the pulmonary valves and 267.30±58.77 pg/mg protein in aortic valves, P=.09). Considering the data presented in this study, we suggest that 8-epi-PGF2α is a valuable indicator of oxidative injury in human semilunar valves.