The gonadotoxic effects of chemotherapy and radiation may result in premature ovarian failure in premenopausal oncology patients. Although autotransplantation of ovarian tissue has led to successful live births, reintroduction of latent malignant cells inducing relapse is a significant concern. In this report, we investigated the design of biomaterial grafts for transplantation of isolated ovar...

The mammalian ovary contains a large number of follicles that are in various developmental stages. The largest portion of them are primordial follicles. However, throughout the female reproductive lifespan only a small proportion of these follicles will produce oocytes competent to undergo successful maturation and ovulation. The rest of the ovarian oocytes (>99.9%) undergo atresia. It would be...

Ovarian dysfunction leading to hormonal imbalance plays a crucial role in uterine carcinogenesis in rats as well as women. However, the effects of a reduction in primordial follicles at birth on uterine adenocarcinoma development have hitherto not been determined. The present study was therefore conducted using female Donryu rats, a high incidence rat strain of uterine adenocarcinoma. The anima...

DNA methylation reprogramming occurs during mammalian gametogenesis and embryogenesis. Sex-specific DNA methylation patterns at specific CpG islands controlling imprinted genes are acquired during this window of development. Characterization of the DNA methylation dynamics of imprinted genes acquired by oocytes during folliculogenesis is essential for understanding the physiological and genetic...

cells of primordial, primary, secondary and antral follicles. Connexin 26 expression in antral follicles was decreased by R diet. The expression of Cx43 in granulosa cells of primary and granulosa and theca layers of antral follicles was increased by HSe in M diet. Thus, maternal diet affected Cx26 and Cx43 expression, and connexins may be differentially involved in regulation of fetal ovarian ...

Under the influence of the AMH formed in the Sertoli cells, the Mullerian ducts degenerate in male fetuses. This leads to the normal development of the male genitals. Female fetuses do not have AMH, and so develop the internal female genital organs. In women, at the onset of puberty AMH, like inhibin B, is formed by the granulosa cells of the maturing ovarian follicle, but not by the primordial...

Primordial follicles, providing all the oocytes available to a female throughout her reproductive life, assemble in perinatal ovaries with individual oocytes surrounded by granulosa cells. In mammals including the mouse, most oocytes die by apoptosis during primordial follicle assembly, but factors that regulate oocyte death remain largely unknown. Proliferating cell nuclear antigen (PCNA), a k...

In mouse ovaries, the first wave of folliculogenesis perinatally starts near the medullary region, which directs the initial round of follicular growth soon after birth. At the same time, cortical primordial follicles start forming in the ovarian surface region, and then some are cyclically recruited for the second and subsequent rounds of follicular growth. Recent studies suggest different dyn...

Mammalian females are born with a finite number of nonrenewing primordial follicles, the majority of which remain in a quiescent state for many years. Because of their nonrenewing nature, these "resting" oocytes are particularly vulnerable to xenobiotic insult, resulting in premature ovarian senescence and the formation of dysfunctional oocytes. In this study, we characterized the mechanisms of...