Gao_2026_Theriogenology_263_117991

Lipid droplets (LDs) undergo extensive dynamic and morphological changes during oocyte maturation, driven by lipases activity, which simultaneously facilitates the production of significant amounts of fatty acids (FAs). As metabolic products of LDs, FAs serve as essential energy substrates during this process. However, excessive lipid accumulation has been shown to negatively impact oocyte developmental competence. Atglistatin (ATGLi), a specific inhibitor of adipose triglyceride lipase (ATGL), reduces triglyceride hydrolysis and consequently limits the release of FAs. The aim of this study was to establish a model of excessive lipid accumulation in porcine oocytes using ATGLi and to evaluate the effect of exogenously supplemented alpha-linolenic acid (ALA) on oocyte developmental competence under ATGLi treatment. The results show that ATGLi treatment significantly induces excessive accumulation of lipid droplets in oocytes, reduces fatty acid content and ATP production, and inhibits oocyte maturation and subsequent early embryo development. Although supplementation with ALA does not reduce excessive lipid droplet accumulation in oocytes, it can restore fatty acid beta-oxidation levels, increase mitochondrial membrane potential and ATP content, thereby improving oocyte maturation and subsequent embryonic developmental competence. In summary, ATGL inhibition leads to disruption of lipid metabolism homeostasis and insufficient energy supply in oocytes, while supplementing with ALA can restore the developmental defects in oocytes caused by ATGL inhibition by promoting fatty acid utilization and improving mitochondrial function.