Abstract

Autophagy is a physiological mechanism that can be activated under stress conditions. However, the role of autophagy during oocyte maturation has been poorly investigated. Therefore, this study characterized the role of autophagy on developmental competence and gene expression of bovine oocytes exposed to heat shock (HS). Cumulus-oocyte-complexes (COCs) were matured at Control (38.5 °C) and HS (41 °C) temperatures in the presence of 0 and 10 mM 3-methyladenine (3MA; autophagy inhibitor). Western blotting analysis revealed that HS increased autophagy marker LC3-II/LC3-I ratio in oocytes. However, there was no effect of temperature for oocytes matured with 3MA. On cumulus cells, 3MA reduced LC3-II/LC3-I ratio regardless of temperature. Inhibition of autophagy during IVM of heat-shocked oocytes (3MA-41 °C) reduced cleavage and blastocyst rates compared to standard in vitro matured heat-shocked oocytes (IVM-41 °C). Therefore, the magnitude of HS detrimental effects was greater in the presence of autophagy inhibitor. Oocyte maturation under 3MA-41 °C reduced mRNA abundance for genes related to energy metabolism (MTIF3), heat shock response (HSF1), and oocyte maturation (HAS2 and GREM1). In conclusion, autophagy is a stress response induced on heat shocked oocytes. Inhibition of autophagy modulated key functional processes rendering the oocyte more susceptible to the deleterious effects of heat shock.

Details

Title
Autophagy is a pro-survival adaptive response to heat shock in bovine cumulus-oocyte complexes
Author
Latorraca Lais B 1 ; Feitosa, Weber B 2 ; Mariano Camila 2 ; Moura, Marcelo T 2   VIAFID ORCID Logo  ; Fontes, Patrícia K 1 ; Nogueira, Marcelo F, G 3 ; Paula-Lopes, Fabíola F 4 

 São Paulo State University (UNESP), Department of Pharmacology, Institute of Bioscience, Botucatu, Brazil (GRID:grid.410543.7) (ISNI:0000 0001 2188 478X) 
 Federal University of São Paulo, Department of Biological Sciences, Diadema, Brazil (GRID:grid.411249.b) (ISNI:0000 0001 0514 7202) 
 São Paulo State University (UNESP), Department of Pharmacology, Institute of Bioscience, Botucatu, Brazil (GRID:grid.410543.7) (ISNI:0000 0001 2188 478X); UNESP, Department of Biological Sciences, School of Sciences and Languages, Assis, Brazil (GRID:grid.410543.7) (ISNI:0000 0001 2188 478X) 
 São Paulo State University (UNESP), Department of Pharmacology, Institute of Bioscience, Botucatu, Brazil (GRID:grid.410543.7) (ISNI:0000 0001 2188 478X); Federal University of São Paulo, Department of Biological Sciences, Diadema, Brazil (GRID:grid.411249.b) (ISNI:0000 0001 0514 7202) 
Publication year
2020
Publication date
2020
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2433603808
Copyright
© The Author(s) 2020. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.