Determination of the appropriate concentration of sodium alginate used for in vitro culture of cat preantral follicles in a serum‐free medium containing FSH, EGF and IGF‐I

Abstract

Culture of domestic cat preantral follicles can be a suitable technology to assist oocyte conservation strategies in the family Felidae. This research was aimed to comparatively analyse cat preantral follicular development of follicles directly seeded on growth surface or encapsulated in 0.5 or 1% of sodium alginate in a serum-free medium containing FSH, EGF and IGF-I. Preantral follicles were isolated from cat ovarian cortical tissue after ovariectomy. Alginate was dissolved at 0.5 or 1% in PBS. Follicles, 4 per well, with 0% (G-0%), 0.5% (G-0.5%) or 1% (G-1%) of sodium alginate were cultured in M199 with FSH (100 ng/mL), EGF (100 ng/mL) and IGF-I (100 ng/mL) for 7 days at 37°C, 5% CO 2 and 99% humidity. Culture medium was replaced every 48 h and samples were stored at −20°C until ELISA of steroid hormones. Morphometric evaluation of follicles was performed every 24 h. G-0% follicles showed granulosa cell migration away from the oocyte and disrupted morphology, whereby they reached apparently larger diameters (203.70 ± 5.82 μm; p < .05) than G-0.5% and G-1% follicles (157.89 ± 8.47 μm and 95.23 ± 1.67 μm, respectively) which maintained threedimensional organization, being larger in G-0.5% than in G-1% (p < .05). G-0.5% follicles attained the multi-layer preantral follicle stage on day 7 of culture, whereas G-1% follicles underwent progressive atresia. On day 6, steroid concentrations were higher (p < .

3D culture applied to reproduction in females: possibilities and perspectives

“…The most commonly used matrix found in 3D studies is alginate ( Vanacker and Amorim, 2017 ; Jones and Shikanov, 2019 ; Correia et al, 2020 ; Fuertes-Recuero et al, 2023 ), which is a natural polymer obtained from different species of brown algae. The alginate hydrogel is formed by the addition of a divalent ion, such as calcium, forming a stable solution with properties similar to the extracellular matrix ( Lee and Mooney, 2012 ).…”