HERP depletion inhibits zearalenone-induced apoptosis through autophagy activation in mouse ovarian granulosa cells

• Published in: Toxicology letters Vol. 301; pp. 1 - 10
• Main Authors: Chen, Fenglei, Wen, Xin, Lin, Pengfei, Chen, Huatao, Wang, Aihua, Jin, Yaping
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.02.2019
• Subjects: Animals; Apoptosis; Apoptosis - drug effects; Autophagy; Cell Line; Cell Survival - drug effects; Female; Gene Deletion; Granulosa cells; Granulosa Cells - drug effects; Granulosa Cells - metabolism; HERP; MAP Kinase Signaling System; Membrane Proteins - genetics; Membrane Proteins - metabolism; Mice; TOR Serine-Threonine Kinases - antagonists & inhibitors; TOR Serine-Threonine Kinases - genetics; TOR Serine-Threonine Kinases - metabolism; Zearalenone; Zearalenone - toxicity; 4-PBA; DMSO; shHERP; Zearalenone; PERK; MTT; Autophagy; BCL-2; 7-AAD; ANOVA; FBS; UPR; mTOR; pERK1/2; Granulosa cells; CHOP; HERP; SPSS; LC3; Fisher LSD; DMEM/F12; GRP78; pS6K1; ER; PVDF; CQ; ECL; S6K1; ERAD; ERK1/2; ATF; ATG; IRE1α; ZEA; BAX; shRNAs; ELISA; shNC; Apoptosis
• ISSN: 0378-4274; 1879-3169
• DOI: 10.1016/j.toxlet.2018.10.026

•ZEA decreases cell viability and increases cell apoptosis in ovarian granulosa cells in a dose-dependent manner.•Autophagy and ER stress cooperate in cell apoptosis in ovarian granulosa cells that is induced by ZEA.•HERP depletion inhibits ZEA-induced cell apoptosis in ovarian granulosa cells through autophagy activation and apoptosis inhibition. HERP is an endoplasmic reticulum (ER) membrane protein and is strongly induced by stress conditions. A recent study has indicated that HERP cooperates in apoptosis during zearalenone (ZEA) treatment. However, regulatory mechanisms and the role of HERP in ZEA-induced apoptosis remain elusive in ovarian granulosa cells. In this study, MTT and flow cytometry assays demonstrated that ZEA gradually decreased cell viability and increased apoptosis in granulosa cells in a dose-dependent manner. Western blot analysis showed that ZEA significantly activated autophagy by upregulating LC3-II. Chloroquine (CQ) significantly increased LC3-II and induced granulosa cell apoptosis. Moreover, Western blot analysis showed that ZEA inhibited the mTOR and ERK1/2 signaling pathways. Furthermore, we found that ZEA activated ER stress by upregulating the ER stress-related proteins GRP78, HERP and CHOP. 4-PBA significantly decreased GRP78, HERP, CHOP and LC3-II. In addition, knockdown of HERP (shHERP) significantly protected ovarian granulosa cells from apoptosis induced by ZEA. We found that HERP depletion activated autophagy and ERK1/2 signaling pathways, while it inhibited the mTOR and caspase-dependent mitochondrial signaling pathways. In summary, autophagy and ER stress cooperated in apoptosis induced by ZEA; HERP depletion inhibits ZEA-induced apoptosis of ovarian granulosa cells through autophagy activation and apoptotic pathway inhibition.