Mechanism for the inhibitory effect of a seleno-organic compound, Ebselen, and its analogues on superoxide anion production in guinea pig polymorphonuclear leukocytes.

Abstract
Effects of Ebselen and its analogs (PZ-25, NAT06-123, NAT02-801, NAT06-099, and NAT06-513) on superoxide anion (O2-) production induced by tetradecanoyl phorbol acetate (TPA) were examined in intact guinea pig polymorphonuclear leukocytes (PMNL). Four compounds having a structure of 1,2 benzoisoselenazol-3-(2H) one (Ebselen, NAT06-123, and NAT02-761) and its sulfur-substituted analog (PZ-25), had a potent inhibitory effect on O2- production as compared with others. Ebselen and NAT06-123 also markedly inhibited nicotinamide dinuclestide phosphate (NADPH) oxidase activity, which is responsible for O2- production in intact cells, and in a particulate fraction prepared from TPA-simulated PMNL, whereas PZ-25 inhibited this enzyme weakly and NAT02-761 did not. On the other hand, Ebselen and PZ-25 had the same degree of potent inhibitory effect on protein kinase C which was involved in the regulation of NADPH oxidase activation. Thus, it is plausible that inhibition of O2- production in intact PMNL by these compounds were due not only to inhibition of NADPH oxidase but also to inhibition of protein kinase C.

This publication has 12 references indexed in Scilit: