Biochemical changes in the cytoplasm of bovine oocytes during the in vitro maturation process: a Raman microscopy study

JIMENEZ, LUIS EMANUEL; ROSA MARÍA SUSANA ALVAREZ; ROLDAN OLARTE, EM; JUAREZ, ANA CAROLINA

VETERINARY RESEARCH COMMUNICATIONS

SPRINGER

Año: 2022 vol. 46 p. 549 - 555

0165-7380

The sequence and chronology of the main biochemical changes occurring in the cytoplasm of bovine oocytes duringthe in vitro maturation process were tracked by Raman microscopy applied to cells previously subjected to enzymaticdigestion of the zona pellucida. Specific spectral markers for proteins, lipids and carbohydrates were used to evaluate thedevelopmental status of the ooplasm at four different times. Spectral changes revealed that lipid accumulation was dominantduring the first six hours of culture while protein content reached the average levels characteristic of mature oocytes withinthe last four hours of the maturation process. A time-dependent decrease in carbohydrates was also observed. Finally, thecarbohydrate-to-protein (P1037/P1002) ratio proved to be sensitive enough to determine the cytoplasmic maturation state ofbovine oocytes and promises to be useful in future research aimed at optimizing culture conditions through the promotionof protein accumulation in the ooplasm.