OOCYTE QUALITY AND AUTOPHAGY: ANALYSIS OF THE RESPONSE TO NUTRIENT DEPRIVATION

ROMANI JE; WETTEN PA; KLINSKY OG; MICHAUT MA

San Juan

Congreso; XLI Reunión Científica Anual de la Sociedad de Biología de Cuyo; 2023

Sociedad de Biología de Cuyo

Oocyte quality (OQ) is crucial to ensure reproductive success. One of the key factors influencing OQ is the oocyte´s ability to maintain its homeostasis and protect itself from cellular damage. Here is where events like autophagy play a crucial role in cellular maintenance. Autophagy is a process of self-digestion and recycling of cellular components. So far, the implication of autophagy in OQ and its role in the cell´s survival and maintenance process is unknown. The aim of this research was to study if autophagy is activated in oocytes exposed to nutrient deprivation conditions (starvation) and determine their ability to recover from this event. To induce autophagy, mature oocytes from CF-1 mice were collected and cultured for 2 hours in starvation medium at 37°C. Then, oocytes were incubated in CZB medium for 1 and 2 hours and the potential cell recovery was assessed. Control cells were maintained in CZB medium for the same times. To analyze the OQ, the cortical granules (CG) density, F-actin cytoskeleton, and microtubule-associated protein light chain 3 (LC3) were analyzed by confocal microscopy. The results showed that under starvation conditions CG density was diminished compared to control cells. The analysis of actin cytoskeleton showed that F-actin was increased in the cytoplasm and cortical F-actin was thicker. LC3-II, a known autophagosomal marker, was present in vesicular-like compartments distributed in all the cytoplasm; nevertheless, after recovery, LC3-II was only observed in the cellular periphery. These preliminary results indicate that autophagy is a cellular process present in mouse oocytes and that the nutrient deprivation alters the oocyte quality.