Considerando o impacto que o estresse oxidativo (EO) e as alterações epigenéticas podem exercer sobre a foliculogênese, o melhor entendimento desses eventos nos auxiliam na busca da melhor eficiência do cultivo in vitro (CIV) de folículos ovarianos em diversas espécies. Diante disso, o objetivo dessa revisão é abordar as principais características e avanços do CIV folicular, expondo as suas limitações (ex. EO e alterações epigenéticas) e alternativas (ex. antioxidantes e meio condicionado de células-tronco mesenquimais - MC-CTMs). Para tanto, no presente artigo foi realizada uma revisão de literatura na qual foram empregadas um total de 143 referências bibliográficas, datadas de 1987 a 2021. Como critérios de inclusão, foram utilizados artigos experimentais, capítulos de livros e revisões de literatura na língua portuguesa, inglesa e espanhola. Em relação aos resultados e discussão, foi observado que os melhores resultados de CIV de folículos ovarianos pré-antrais foram obtidos em murinos com o nascimento de crias saudáveis. Atualmente os entraves dessa biotécnica têm sido correlacionados às condições inadequadas de cultivo, que causam aumento do EO e alterações nos padrões epigenéticos do folículo (oócitos e células somáticas). Dessa maneira, para transpor esse problema, vem-se testando a adição de diferentes substâncias ao meio de CIV, como antioxidantes, e meios oriundos do CIV de CTMs (ex. MC).
Contents
This study aimed to examine the in vitro culture of secondary preantral follicles, using reused ovaries, to compare both the 2D and 3D methods of in vitro culture of preantral follicles, and the system of medium replacement. Twenty‐five pairs of ovaries from mixed‐breed goats were used for the experiment. Follicular puncture of antral follicles was performed for in vitro production. After this procedure, the secondary preantral follicles were submitted to a microdissection procedure. The isolated preantral follicles were randomly divided into three treatments: (a) Two‐dimensional culture with partial replacement of medium during culture (2D PR), (b) Three‐dimensional culture with addition of medium during culture (3D AD) and (c) Three‐dimensional culture with partial replacement of medium (3D PR). The culture period was 18 days. All treatments at the end of the in vitro culture period (18 days) presented a follicular survival rate which ranged from 59% to 70%, demonstrating that it was possible to perform an experiment with preantral follicles using ovaries that had previously been used in another reproductive biotechnique. The 3D AD treatment showed a survival percentage and follicular diameter higher than the 2D PR treatment, however, it did not differ from the 3D PR treatment. In conclusion, experiments employing the use of preantral follicles can be performed with success after the ovaries have been used for experiments with antral follicles. Moreover, the three‐dimensional system with the addition of medium is recommended for in vitro culture of preantral follicles, since this system is more practical and financially feasible.
To compare the efficiency of North Carolina State University medium 23 (NCSU23) and Alpha Minimum Essential Medium (α-MEM) as a base medium, and to evaluate the effects of Anti-Müllerian Hormone (AMH) alone or in combination with Follicle Stimulating Hormone (FSH) on the in vitro development and steroid production of isolated porcine preantral follicles. Porcine secondary follicles were cultured in NCSU23 or α-MEM media for 4 days. Once α-MEM was determined to be the optimal culture medium, secondary follicles were cultured in α-MEM alone or supplemented with FSH (1.5 ng/mL), AMH (50 ng/mL) or the combination of the two hormones. Follicle development was evaluated by measuring follicular growth, morphology and hormone production. There was no difference between the media NCSU23 and α-MEM in terms of follicle survival and growth (P > 0.05). However, at day 2, the antrum formation rate tended to be (P < 0.074) higher in α-MEM than NCSU23. At day 4 of culture, the estradiol and progesterone secretion were higher in α-MEM than NCSU23 (P < 0.01), while the opposite was observed for testosterone (P < 0.01). The addition of AMH and/or FSH did not affect follicular survival and growth. Nevertheless, the secretion of estradiol and progesterone induced by FSH was reduced with AMH (P < 0.01). α-MEM is a more effective base medium than NCSU23 for the in vitro follicular development of pig preantral follicles and AMH reduces the steroid production induced by FSH.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.