Kit ligand decreases the incidence of apoptosis in cultured vitrified whole mouse ovaries

Abstract

To investigate the development of follicles and incidence of apoptosis in vitrified cultured mouse ovaries in the presence and absence of Kit ligand, 1-week-old mouse ovaries were cultured in the presence or absence of Kit ligand for 7 days. Development and function of ovarian follicles was evaluated by histology and hormonal analysis. Apoptosis assessment was conducted by analysis of DNA laddering, TdT (terminal deoxynucleotidyl transferase)-mediated dUDP nick-end-labelling and caspase-3/7 activity. The proportion of preantral follicles and the level of 17-β oestradiol, progesterone and dehydroepiandrosterone were increased in all cultured groups, and it was significantly higher in Kit ligand treated groups than in the control (P < 0.001). The number of apoptotic signals in both vitrified samples is significantly higher than in the non-vitrified control (P < 0.01), and these signals are significantly lower in both Kit ligand treated groups than in non-Kit ligand treated groups (P < 0.001). The level of caspase-3/7 activity was higher in vitrified cultured ovaries than non-vitrified group (P < 0.01). Kit ligand was shown to improve in-vitro development of follicles, and also acted as an anti-apoptotic factor in vitrified ovaries. The developmental potential of follicles in vitrified groups was lower than that in fresh ovaries.

The mitochondrial DNA copy number, cytochrome c oxidase activity and reactive oxygen species level in metaphase II oocytes obtained from in vitro culture of cryopreserved ovarian tissue in comparison with in vivo‐obtained oocyte

“…We have previously shown that the negative effect of vitrification after one‐step in vitro culture of whole mouse ovaries on the developmental of follicles within these tissues, and a significant decline in the percent of normal follicles was demonstrated in vitrified samples than the nonvitrified group . Otherwise, the results of the present study showed that, after the two‐step in vitro culture of vitrified mouse ovaries, the rates of isolated follicles development, oocyte maturation, fertilization and blastocyst formation was similar to nonvitrified once.…”

“…Preantral follicles (140–150 μm in diameter) were mechanically isolated from in vitro ‐cultured ovaries ( n > 170 in each group) under stereomicroscope. Then, to evaluate the survival rate, the isolated preantral follicles ( n = 20 in each group) were stained with 0.4% trypan blue . The surviving follicles were not stained, damaged follicles were stained moderately, and degenerated follicles were stained blue.…”

The role of FSH and TGF-β superfamily in follicle atresia

“…Bo Zhai’s work showed that BMP-15 may prevent the apoptosis of cumulus cells in cooperation with CCL2 [ 77 ]. Kit ligand, also called stem cell factor, is known to promote granulosa cell proliferation, and can function as an anti-apoptotic factor of follicle growth at different stages [ 80 , 81 ]. BMP-15 can stimulate KL expression in mammalian ovaries, and it seems that there exists a negative feedback loop between BMP-15 and KL while BMP-15 directly elevates the level of KL.…”

Chlorogenic acid improves functional potential of follicles in mouse whole ovarian tissues in vitro

“…In vitro culture (IVC) system of ovarian tissue is a considerably interesting alternative approach to improve the reproductive potential and preserve female fertility [1]. Many researchers have also been committed to de ning the optimal maturation condition (physical and biochemical condition) for the IVC system of ovarian tissue [2][3][4][5]. Despite the proposed designation of IVC systems, the improvement of this type of culture system is challenging because the survival rate of follicles, maturation rate of oocytes, and embryo development are still low compared with in vivo [6,7].…”