background: one of the most major obstacles of ovarian tissue vitrification is suboptimal developmental competence of follicles. matrix metalloproteinases 2 (mmp-2) and 9 (mmp-9) and their tissue inhibitors timp-1 and timp-2 are involved in the remodeling of the extracellular matrix in the ovaries. objective: this study aimed to evaluate the expression of mmp-2, mmp-9, timp-1, and timp-2 genes ...

Although hormonal regulation of ovarian follicle development has been extensively investigated, most studies concentrate on the development of early antral follicles to the preovulatory stage, leading to the successful use of exogenous FSH for infertility treatment. Accumulating data indicate that preantral follicles are under stringent regulation by FSH and local intraovarian factors, thus pro...

Activins have been implicated as important regulating factors for many reproductive processes. The aim of this study was to determine the effect of activin A on the development of ovine preantral follicles in vitro. Mechanically isolated preantral follicles (161 +/- 2 microm) were cultured for 6 days in the presence of human recombinant activin A (0, 10 and 100 ng/ml). Half of the medium was re...

BACKGROUND The aim of this study was to evaluate fibroblast co-culture on in vitro maturation and fertilization of prepubertal mouse preantral follicles. MATERIALS AND METHODS The ovaries of 12-14 day old mice were dissected and 120-150 μm intact preantral follicles with one or two layers of granulosa cells, and round oocytes were cultured individually in α-minimal essential medium (α-MEM) su...

Introduction: Melatonin acts as an indirect antioxidant and is a powerful direct free radical scavenger and direct responses to melatonin in the gonads are detected. This study aims to investigate the influence of different doses of melatonin on preantral follicle development and oogenesis of in vitro cultured mouse ovarian follicles. Materials and Methods: Preantral follicles with diamet...

background: in vitro maturation (ivm) of oocytes reduces the costs and averts the side-effects of gonadotropin stimulation for in vitro fertilization (ivf). reliable ivm is an intellectual, scientific and clinical challenge with a number of potential applications. objective: the effect of hcg was evaluated on the timing and regulation of in vitro ovulation for the syrian mice oocytes in the pre...

objective: growth differentiation factor 9b (gdf9b) is an oocyte-derived growth factor. this protein is essential for the development of ovarian follicles and acts mainly by binding to its receptor on the surface of granulosa cells. the effect of gdf9b on the growth of follicles in various developmental stages, particularly primordial and primary follicles, is unknown. thus the aim of this stud...

BACKGROUND There is substantial evidence both in humans and in animals that a prolonged reduction in plasma thyroid hormone concentration leads to reproductive problems, including disturbed folliculogenesis, impaired ovulation and fertilization rates, miscarriage and pregnancy complications. The objective of the present study is to examine the consequences of chronic hypothyroidism, induced in ...

The toxicity of QD has been extensively studied over the past decade. However, the potential toxicity of QDs impedes its use for clinical research. In this work, we established a preantral follicle in vitro culture system to investigate the effects of QD-Transferrin (QDs-Tf) bioconjugates on follicle development and oocyte maturation. The preantral follicles were cultured and exposed to CdTe/Zn...