Paraptosis ‐like cell death in Wistar rat granulosa cells

This study found swollen endoplasmic reticulum in the granulosa cells of adult Wistar rats. Calnexin was used as a marker of the endoplasmic reticulum at the ultrastructural and optical levels. The cells with swelling of the endoplasmic reticulum were negative to the TUNEL assay and active caspase‐3 immunodetection, indicating that this swelling is not part of any apoptotic or autophagic process. Additionally, immunodetection of the CHOP protein was used as a marker of endoplasmic reticulum stress, and this confirmed the presence of the paraptosis process. These data suggest that paraptosis‐like cell death is associated with the death of granulosa cells during follicular atresia in adult Wistar rats.

The follicular atresia is a normal process in mammals' ovaries. Along this process the non‐selected oocytes to be ovulated are degraded. It has been described that during atresia, the apoptosis has been identified as the main route of elimination; however, some ultrastructural characteristics observed in the granulosa cells during the atretic process are not corresponding to the classical apoptotic process. In this work we have evidenced that those altered morphology is corresponding with the paraptosis process, which is characterized by the endoplasmic reticulum being swollen, no presence of active caspase‐3, and the fragmented chromatin is absent.

Source: Development, Growth and Differentiation - August 31, 2016 Category: Research Authors: Nayeli Torres ‐Ramírez, María L. Escobar, Gerardo H. Vázquez‐Nin, Rosario Ortiz, Olga M. Echeverría Tags: Original Article Source Type: research