2] began to be produced in
theca cells, granulosa acting on paracrine manner and is involved in the induction of LH surge before ovulation, and this is motivated by the increased sensitivity to LH in granulosa cells, respectively.
This study demonstrates a reduction in inhibin-[beta]A expression during the transition of primary follicles to the secondary stage, and its increase in mural granulosa /
theca cell complexes during the development of antral follicles.
One can argue that this spindle cell component is truly another pattern of granulosa cell tumor (pseudosarcomatous pattern) or it might represent a fibrothecomatous component, taking into consideration that most granulosa cell tumors have at least some
theca cells focally.
In vivo and in vitro studies later confirmed this hypothesis, showing that inositol glycans had insulin mimetic effects in human ovarian
theca cells and stimulated testosterone biosynthesis [49, 50].
In women with PCOS, though, the insulin resistance is commonly associated with hyperinsulinemia, which then enhances the production of androgens by the ovarian
theca cells, leading to a reduction in circulating levels of SHBG, which leads to increased levels of free testosterone.
The increase in estrogen in group C compared to group B might be due to increase of LH hormone that leads to increase of its binding with the receptors on
theca cells [21].
The main hormone produced from 17[alpha]-hidroxiprogesterone is androstenedione, which can be converted to testosterone by the isoenzyme 17[beta]-hidroxisteroide deidrogenase (HSD17B) in
theca cells or to estrone by aromatase (CYP19A1) in granulosa cells.
High levels of FSH and LH in the GFF to stimulate follicular development and granulosa cells and
theca cells so as to increase the secretion of estrogen as well as LH and FSH stimulates the maturation of acolytes contained within follicles.
Ovarian aromatase expressed in granulosa cells facilitates the conversion of E2 from androgens produced in the
theca cells of the antral follicles.
The pathophysiology of PCOS is complex involving the hypothalamus-pituitary-ovarian axis, ovarian
theca cells hyperplasia, hyperinsulinemia and a multitude of either cytokines and adipocyte driven factors.
A row of granulosa cells and few
theca cells are also presents (Fig.
The creation of an artificial ovary is the first time researchers have successfully created a three-dimensional environment that contains the three main types of ovarian cells:
theca cells, granulose cells and eggs or oocytes.
