Interplay of Oxidative Stress, Autophagy, and Rubicon in Ovarian Follicle Dynamics: Orchestrating Ovarian Aging

Abstract

Organ functions generally decline with age, but the ovary is a prototypical organ that undergoes functional loss over time. Autophagy plays a crucial role in maintaining organ homeostasis, and age-related upregulation of the autophagy inhibitor protein, Rubicon, has been linked to cellular and tissue dysfunction. This review describes how granulosa cell autophagy supports follicular growth and oocyte selection and maturation by regulating cellular energy metabolism and protein quality control. We then introduce the role of selective autophagy, including mitophagy or lipophagy, in steroidogenesis and cellular remodeling during luteinization. In aged ovaries, Rubicon accumulation suppresses autophagic flux, leading to diminished oxidative-stress resilience and enhanced DNA damage. Moreover, impaired autophagy drives the accumulation of ATP citrate lyase, which correlates with poor oocyte quality and reduced ovarian reserve. Following fertilization, oocytes further upregulate autophagy to provide the energy required for blastocyst transition. Conversely, in infertility-related disorders, such as premature ovarian insufficiency, endometriosis, and polycystic ovary syndrome, either deficient or excessive autophagy contributes to disease pathogenesis. Both autophagy inhibitors (e.g., Rubicon) and activators (e.g., Beclin1) could be emerging as promising biomarkers for assessing ovarian autophagy status. Therapeutically, Rubicon inhibition by trehalose in aged ovaries and autophagy suppression by agents such as hydroxychloroquine in polycystic ovary syndrome and endometriosis hold potential. Establishing robust methods to evaluate ovarian autophagy will be essential for translating these insights into targeted treatments.