Effects of Betaine on m6A Methylation, AMPK Signalling and Cytoplasmic Maturation in Porcine Oocytes

In vitro maturation (IVM) of oocytes is crucial in livestock breeding. Oocytes obtained by IVM are more susceptible to oxidative stress than in vivo, leading to low maturation rates. Betaine from red beetroot acts as an antioxidant and methyl donor, regulating epigenetic modifications in cell physiology. This study investigates Betaine's effects on porcine oocyte IVM, embryo development and underlying molecular mechanisms. Results demonstrate that 16 mmol/L Betaine significantly enhances the first polar body extrusion, cleavage and blastocyst rates compared to the control and other concentrations. Betaine elevates normal cortical granule distribution, normal spindle assembly, normal chromosome arrangement and overall m6A levels during IVM. It increases the antioxidant gene expression and mitochondrial function and decreases reactive oxygen species levels. However, Betaine's beneficial effects were diminished by AMPK inhibitor compound C. In conclusion, Betaine enhances porcine oocyte IVM and early embryo development by enhancing the antioxidant capacity and mitochondrial function pathway.