Involvement of a mitochondrial pathway and key role of hydrogen peroxide during eosinophil apoptosis induced by Excretory-Secretory Products from Fasciola hepatica

SERRADELL MC; GUASCONI L; MASIH DT

Elsevier

Lugar: Amsterdam; Año: 2009 vol. 163 p. 95 - 95

osinophils (Eo) are typically associated with immune response to helminth. Previously, we demon-strated that excretory?secretory products (ESP) from Fasciola hepatica induce eosinophil apoptosis by a caspase-dependent mechanism. In this study, we observed that ESP caused mitochondrial-membrane depolarization of eosinophils leading to the release of cytochrome c. Also, ESP induced an increase in the reactive oxygen species (ROS) production, which preceded the mitochondrial injury. We found a signif-icant rise in hydrogen peroxide, but not in the anion superoxide levels. Furthermore, catalase, but not superoxide dismutase, inhibited the mitochondrial depolarization as well as apoptosis. So, ESP induce in Eo an early increase in the ROS production, mainly hydrogen peroxide, which precedes mitochondrial injury and leads again to apoptosis. Finally, we demonstrated the participation of hydrogen peroxide in the peritoneal Eo apoptosis in vivo, both during the early stages of experime