One of the critical challenges in assisted reproductive technology (ART) is the inadequacy of effective regulation of reactive oxygen species. Simultaneously, the endogenous antioxidant defense system plays a significant role in combating oxidative stress across various physiological stages of embryonic development. However, these intrinsic defense systems alone are insufficient as they rely on exogenous antioxidants that interact synergistically to enhance and sustain antioxidant capacity. Considering the principal role of antioxidants in mitigating oxidative stress in oocyte growth, identifying reliable and non-toxic antioxidants is an essential prerequisite for effective therapeutic applications. Thus, owing to the need to explore exogenous antioxidants, we attempted to summarize and analyze the literature data defining the potential use of curcumin in mitigating oxidative stress to promote oocyte maturation through in vivo and in vitro model studies. Recent studies demonstrated the protective role of curcumin against oxidative stress and the inflammatory response, primarily through the upregulation of key antioxidant enzymes (including SOD, CAT and GPx), a reduction in oxidative stress markers (e.g., ROS, MDA) and by suppressing the pro-inflammatory signaling pathways (such as NF-kB, JAK/STAT) while activating the NRF2/HO-1 pathway to further enhance the cellular antioxidant defense. Advancing curcumin as a therapeutic agent necessitates a thorough understanding of curcumin’s molecular mechanisms and targeted pharmacological effectiveness to treat female infertility, and despite the progress in enhancing curcumin’s bioavailability, the optimal dosing strategies still need to be defined. Future studies are required to develop strategies to augment antioxidant defense mechanisms (modeling in vivo and in vitro studies) using curcumin with a specific emphasis on curcumin’s role in improving mitochondrial activity. This approach is expected to represent a significant advancement in the field of medicine, offering novel therapeutic possibilities.

Sodium butyrate (NaBu), a common feed additive, has been shown to enhance reproductive performance in livestock and poultry. However, whether NaBu exerts this effect by directly regulating follicular development remains unclear. In this study, a three-dimensional (3D) in vitro culture system of mouse preantral follicles was used to investigate the effects of NaBu on follicular growth, hormone secretion, maturation of oocytes, and subsequent embryonic development. Preantral follicles were treated with different doses of NaBu on the fourth day of culture. Subsequently, the mature oocytes (MII stage) were released from the follicles on the ninth day and subjected to parthenogenetic activation for developmental assessment. The results showed that 0.10 mM NaBu treatment could significantly promote follicular growth, antral formation, and oocyte maturation. Furthermore, NaBu also significantly increased estradiol (E₂) secretion, improved follicular structure, and maintained cellular viability. qPCR analysis revealed that NaBu significantly increased the mRNA levels of STAR, CYP11A1, and CYP1B1. In addition, it significantly enhanced the distribution and organization of F-actin, with increases in the mRNA levels of GDF9, BMP15, and CX37. NaBu treatment significantly reduced intracellular ROS levels and increased the mRNA levels of NRF2 and SOD1, while SOD2 and GSR showed increasing trends without significant differences. NaBu significantly improved oocyte cytoskeletal organization and the morphology of the spindle, but it did not lead to a significant increase in the rates of cleavage and blastocyst formation after parthenogenetic activation. Collectively, these findings indicate that NaBu promotes follicular development and improves oocyte quality, at least partly, by enhancing steroidogenesis, alleviating oxidative stress, and maintaining cytoskeletal integrity, providing insight into its potential application for improving reproductive performance in livestock and poultry.

Histone deacetylase 2 (HDAC2)-mediated epigenetic modifications play a crucial role in oogenesis, yet the regulatory mechanisms of HDAC2 throughout the entire process of folliculogenesis remain elusive. In the present study, the localization and expression of HDAC2 were detected in mouse ovaries at distinct postnatal ages and after gonadotropin treatment. The effects and molecular mechanisms of Santacruzamate A (SCA), a selective HDAC2 inhibitor, on folliculogenesis were investigated via an in vitro 3D culture model of mouse preantral follicles. The results showed that HDAC2 was localized in the nuclei of both ovarian granulosa cells and oocytes. Its expression was gradually increased with ovarian development in mice aged from postnatal day 7 to 21, and significantly decreased after 12 h hCG treatment. In follicles cultured in vitro, HDAC2 expression peaked on day 4 of culture. SCA exerted stage-specific and dose-dependent regulatory effects on folliculogenesis. SCA significantly suppressed follicular growth, blocked antrum formation, and triggered follicular atresia. Mechanistically, SCA promoted ovarian granulosa cell apoptosis via increases in pro-apoptotic genes BAX and Caspase-3 levels, and a decrease in anti-apoptotic gene BCL-2 level. Furthermore, SCA disrupted the structural integrity of the follicular microfilament cytoskeleton, interfered with the levels of genes related to oocyte–granulosa cell communication including CX37 and GDF9, caused abnormalities in oocyte spindle structure, chromosome alignment, mitochondrial distribution, and decreased mitochondrial membrane potential (ΔΨm). In conclusion, HDAC2 participates in the transcriptional regulation of mouse folliculogenesis through dynamically changing expression at distinct developmental stages. HDAC2 exerts stage-specific regulatory effects on follicular growth and oocyte maturation, and its mechanisms are associated with maintaining granulosa cell survival, ensuring cytoskeletal integrity, and preserving oocyte mitochondrial function. This study advances our understanding of epigenetic regulation of folliculogenesis and provides novel targets and an experimental basis for optimizing in vitro follicular culture systems and regulating female reproductive performance.