In vitro matured bovine oocytes in the presence of vascular endothelial growth factor–D: A Raman spectroscopy analysis

Raman microscopy is a powerful tool for examining mammalian female gametes and identifying molecular markers to evaluate their competence after in vitro maturation (IVM). However, its application to comprehensively analyze the biochemical changes induced in oocytes by vascular endothelial growth factor D (VEGF–D) enrichment during IVM remains largely unexplored, although various media supplements are commonly used to optimize IVM protocols. This study presents the first application of Raman spectroscopy to investigate the effect of VEGF–D supplementation on the biochemical composition of in vitro matured bovine oocytes. Spectral profiles of zona pellucida-free oocytes matured for 18 and 22 hours in standard and VEGF–Denriched media were compared. The differences in specific marker bands were correlated with the attained maturational status. Multivariate statistical analysis supported the spectral interpretations, revealing an increased overall content of proteins, lipids, and carbohydrates in the cytoplasm of oocytes matured in the presence of VEGF–D. This sensitive methodology shows promise for improving culture conditions and enhancing in vitro maturation rates in future research.