Endocrine and local control of the primate corpus luteum

Abstract

The primate corpus luteum is a transient endocrine gland that differentiates from the ovulatory follicle midway through the ovarian (menstrual) cycle. Its formation and limited lifespan is critical for fertility, as luteal-derived progesterone is the essential steroid hormone required for embryo implantation and maintenance of intra-uterine pregnancy until the placenta develops. It is well-established that LH and the LH-like hormone, CG, are the vital luteotropic hormones during the menstrual cycle and early pregnancy, respectively. Recent advances, particularly through genome analyses and cellular studies, increased our understanding of various local factors and cellular processes associated with the development, maintenance and repression of the corpus luteum. These include paracrine or autocrine factors associated with angiogenesis (e.g., VEGF), and that mediate LH/CG actions (e.g., progesterone), or counteract luteotropic effects (i.e., local luteolysis; e.g., PGF2α). However, areas of mystery and controversy remain, particularly regarding the signals and events that initiate luteal regression in the non-fecund cycle. Novel approaches capable of gene “knockdown” or amplification”, in vivo as well as in vitro, should identify novel or underappreciated gene products that are regulated by or modulate LH/CG actions to control the functional lifespan of the primate corpus luteum. Further advances in our understanding of luteal physiology will help to improve or control fertility for purposes ranging from preservation of endangered primate species to designing novel ovary-based contraceptives and treating ovarian disorders in women. R01 HD020869, R01 HD042000, U54 HD018185, U54 HD055744, P51 OD011092, T32 HD007133, Bayer Schering Pharma AG.

Prolyl oligopeptidase regulates progesterone secretion via the ERK signaling pathway in murine luteal cells

“…The main function of luteal cells is the synthesis of steroid hormones. Stouffer et al (). We find that progesterone secretion is significantly increased by POP overexpression.…”

Dual role for the unfolded protein response in the ovary: adaption and apoptosis

“…The main function of the corpus luteum is to synthesize and secrete progesterone, which is indispensable for maintenance of pregnancy and regulation of the estrous cycle (Stouffer 2003; Devoto et al, 2009). The luteal phase can be divided into three main stages, namely development, maintenance, and regression, according to the macroscopic appearance of corpus luteum tissues (Stouffer et al, 2013). The pathway for progesterone synthesis mainly involves three steroidogenic enzymes, namely steroidogenic acute regulatory protein (known as StAR), p450 cholesterol side-chain cleavage enzyme (p450), and 3β-hydroxysteroid dehydrogenase, and two cellular organelles (mitochondria and ER) (Niswender 2002; Rekawiecki et al, 2008).…”

Non-canonical progesterone signaling in granulosa cell function

“…Specifically, inhibiting P4 synthesis results in structural changes similar to those associated with luteal regression (See review by (Stouffer, et al 2013). These changes are prevented by supplemental P4 treatment (Stouffer, et al 2013). However, the effect of RU486 treatment is variable; at times increasing while at other times decreasing P4 secretion.…”