Characterization of the Lipid Profile of Immature and In Vitro Matured Cat Oocytes

Forskolin (FSK), l-carnitine (LC), and Conjugated Linoleic Acid (CLA) are lipid modulators that reduce cellular lipid content. This study characterizes the lipid profile and mRNA content of immature and in vitro matured cat oocytes with or without a MIX of these modulators. Ovaries were collected, COC retrieved, and allocated into three groups: immature (IM), matured without (CONT), or with FSK, LC, and CLA (MIX). Lipid analysis was performed using High-performance thin-layer chromatography, gene expression by RT-qPCR, and oocytes stained with Nile Red, Oil Red O, and Sudan Black B. Eight lipid subclasses were detected in all groups. Esterified sterol was more abundant in CONT than IM, with intermediate levels in MIX. Triacylglycerol was higher in MIX than IM, while monoacylglycerol increased in both CONT and MIX. In MIX, DGAT1, FABP3, and PLIN2 were upregulated compared to IM. Moreover, in IM, DGAT1 was downregulated and FABP3 upregulated relative to CONT. FABP3 levels were higher in MIX than CONT. Oil Red O and Sudan Black B staining showed reduced lipid content in MIX compared to CONT, while Nile Red detected no difference. In conclusion, feline oocytes subjected to MIX during in vitro maturation exhibited increased triacylglycerol levels and enhanced FABP3 expression.