Trimethylation profile of histones H3 lysine 4 and 9 in late preantral and early antral caprine follicles grown in vivo versus in vitro in the presence of anethole

This study assessed the histones methylation profile (H3K4me3 and H3K9me3) in late preantral (PA) and early antral (EA) caprine follicles grown in vivo and in vitro, and the anethole effect during in vitro culture of PA follicles. Uncultured in vivo–grown follicles (PA, n = 64; EA, n = 73) were used as controls to assess the methylation profile and genes' expression related to apoptosis cascade (BAX, proapoptotic; BCL2, antiapoptotic), steroidogenesis (CYP17, CYP19A1), and demethylation (KDM1AX1, KDM1AX2, KDM3A). The isolated PA follicles (n = 174) were cultured in vitro for 6 days in α-MEM⁺ in either absence (control) or presence of anethole. After culture, EA follicles were evaluated for methylation, mRNA abundance, and morphometry. Follicle diameter increased after culture, regardless of treatment. The methylation profile and the mRNA abundance were similar between in vivo–grown PA and EA follicles. Anethole treatment led to higher H3K4me3 fluorescence intensity in EA follicles. The mRNA abundances of BAX, CYP17, and CYP19A1 were higher, and BCL2 and KDM3A were lower in in vitro–grown EA follicles than in vivo–grown follicles. In conclusion, in vitro follicle culture affected H3K4me3 fluorescence intensity, mRNA abundance of apoptotic genes, and steroidogenic and demethylase enzymes compared with in vivo–grown follicles.