Mono-(2-ethylhexyl) phthalate (MEHP) affects intercellular junctions of Sertoli cell: A potential role of oxidative stress

Abstract

We analyzed the potential role of oxidative stress induced by mono (2-ethylhexyl) phthalate (MEHP) in adherent cell junction protein expression of prepubertal rat Sertoli cells (SC) in vitro. Five-day SC cultures were treated with MEHP (200 µM) for 24h and compared to cells in basal conditions. Western blot and immunofluorescent (IF) analyses showed that MEHP induced increase of N-cadherin and catenin expression, modifying its distribution. Concomitantly, Cx-43 expression decreased significantly and delocalization of the IF signal for tight junction proteins (occludin, claudin-11 and ZO-1) occurred. Indicative of oxidative stress, MEHP induced in SC an increase of lipoperoxides, a decrease in glutathione (GSH) levels and a concomitant increase in Glutathione S-Transferases (GST) activity. Antioxidant N-acetyl-cysteine (1mM) treatment prevented GSH decrease and N-cadherin and α-catenin up-regulation induced by MEHP. Our data suggest that oxidative stress signaling is a mechanism involved in adherent cell junctions disruption induced by MEHP in SC cultures.