The regulatory mechanisms of early follicle development are not clearly understood. Although relaxin is a peptide that controls cell proliferation and differentiation in many tissues, its role in human follicular development is unclear. In this study we cultured slices of human ovarian cortical tissue in the presence and absence of recombinant human relaxin. Ovarian tissue was obtained by biops...

Fetal ovarian development and primordial follicle formation are imperative for adult fertility in the female. Data suggest the interleukin (IL)6-type cytokines, leukaemia inhibitory factor (LIF), IL6, oncostatin M (OSM) and ciliary neurotrophic factor (CNTF), are able to regulate the survival, proliferation and differentiation of fetal murine germ cells (GCs) in vivo and in vitro. We postulated...

Primordial ovarian follicles in mice form when somatic cells surround individual oocytes. We show that lack of Nobox, an oocyte-specific homeobox gene, accelerates postnatal oocyte loss and abolishes the transition from primordial to growing follicles in mice. Follicles are replaced by fibrous tissue in female mice lacking Nobox in a manner similar to nonsyndromic ovarian failure in women. Gene...

Primordial follicles comprise an oocyte surrounded by a single layer of squamous epithelial cells, called pregranulosa cells (Peters, 1978; Greenwald and Terranova, 1988). Enlargement of the oocyte and initiation of granulosa cell division mark the beginning of follicular growth (Peters, 1978). Soon after initiation of growth, the pregranulosa cells, which form the simple squamous epithelium of...

BACKGROUND The forkhead transcription factor Foxo3 is a master regulator and potent suppressor of primordial follicle activation. Loss of Foxo3 function in the mouse leads to premature ovarian failure (POF) due to global follicle activation. METHODS AND RESULTS Here, we show that the mouse Foxo3 locus is haploinsufficient, and that Foxo3-/+ females undergo early reproductive senescence consis...

Follicular development begins as early as the fourth month of fetal life [1]. At that time, the primordial germ cells (PGCs) have migrated from the yolk sac endoderm to the gonadal ridge, undergoing mitotic divisions. PGCs are called oogonia once they reach the gonads, then the oogonia enter the first meiotic division and become primary oocytes. Somatic cells originating from the primitive gona...

The last several years have produced a great deal of evidence supporting the once revolutionary notion that the formation of the ovary is a directed rather than passive process. For example, factors such as follistatin, respondin-1, and Wnt-4 are differentially expressed in the XX gonad and appear to play a pivotal role in differentiation of the bipotential ovary (1). Primordial germ cells are ...

The aim of the present study was to investigate the effects of activin-A and follistatin on in vitro primordial and primary follicle development in goats. To study primordial follicle development (experiment 1), pieces of ovarian cortex were cultured in vitro for 5 days in minimal essential medium (MEM) supplemented with activin-A (0, 10 or 100 ng/ml), follistatin (0, 10 or 100 ng/ml) or combin...

In the female fetus oocyte numbers peak by 16 weeks of gestation, reaching up to 7 million. They decrease progressively and at the time of birth a female will have about 2 million eggs. As she approaches menarche the woman will have about 500,000. This primordial follicular disappearance continues throughout reproductive life and accelerates approximately 10 years prior to the menopause, by whi...