Acetyl-L-carnitine increases follicle survival and stromal cell density in cultured bovine ovarian tissues.

This study aimed to evaluate the effects of acetyl-L-carnitine on follicle survival and growth, stromal cell density and extracellular matrix, as well as on the expression of mRNA for nuclear factor erythroid 2-related factor (NRF2), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and peroxiredoxin 6 (PRDX6) in cultured bovine ovarian cortical tissues. Ovarian fragments (3 × 3 × 1 mm) were cultured for 6 days in α-MEM⁺ alone or supplemented with 10, 50 or 100 μM acetyl-L-carnitine at 38.5°C with 5% CO₂ in humidified air. Before (non-cultured tissues) and after culture, the ovarian fragments were fixed in 4% paraformaldehyde for 12 h for histological analysis or stored at -80ºC for mRNA expression analysis of NRF2, SOD, CAT, PRDX6 and GPX1. The results showed that 100 μM acetyl-L-carnitine increased the percentages of morphologically normal follicles and stromal cell density in cultured ovarian tissues. On the other hand, acetyl-L-carnitine did not influence the percentage of collagen in ovarian tissue nor the expression of mRNAs for NRF2, SOD, CAT, PRDX6 and GPX1. In conclusion, 100 μM acetyl-L-carnitine increased follicle survival and stromal cell density in cultured bovine ovarian tissues but does not influence collagen fibre distribution or the expression of mRNAs for NRF2, SOD, CAT, PRDX6 and GPX1.