Effect of neopterin and 7,8‐dihydroneopterin on tumor necrosis factor‐α induced programmed cell death

Abstract
Tumor necrosis factor‐α and the formation of reactive oxygen intermediates are central mediators of apoptosis. Recent data indicated a role of neopterin and 7,8‐dihydroneopterin in oxygen radical mediated processes. We have therefore investigated the effect of neopterin‐derivatives on TNFα induced apoptosis of the monocyte‐like cell line U937. At an elevated concentration 7,8‐dihydroneopterin was found to superinduce TNFα mediated programmed cell death due to the formation of reactive oxygen intermediates. Our results imply that in combination with TNFα high concentrations of 7,8‐dihydroneopterin enhances apoptosis due to oxidative stress on cells.