Oral follicle-stimulating hormone receptor agonist affects granulosa cells differently than recombinant human FSH
Joie Z Guner1, Diana Monsivais2, Henry Yu3
1Center for Drug Discovery, Baylor College of Medicine, Houston, Texas; Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Southern California, Los Angeles, California.
Objective:
To determine whether TOP5300, a novel oral follicle-stimulating hormone (FSH) receptor (FSHR) allosteric agonist, elicits a different cellular response than recombinant human FSH (rh-FSH) in human granulosa cells from patients undergoing in vitro fertilization.
Design:
Basic science research with a preclinical allosteric FSHR agonist.
Setting:
University hospital.
Patient(S):
Patients with infertility at a single academic fertility clinic were recruited under an Institutional Review Board-approved protocol. Primary granulosa cell cultures were established for 41 patients, of whom 8 had normal ovarian reserve (NOR), 17 were of advanced reproductive age (ARA), 12 had a diagnosis of polycystic ovary syndrome (PCOS), and 4 had a combination of diagnoses, such as ARA and PCOS.
Intervention(S):
Primary granulosa-lutein (GL) cell cultures were treated with rh-FSH, TOP5300, or vehicle.
Main Outcome Measure(S):
Estradiol (E2) production using enzyme-linked immunosorbent assay, steroid pathway gene expression of StAR and aromatase using quantitative polymerase chain reaction, and FSHR membrane localization using immunofluorescence were measured in human GL cells.
Result(S):
TOP5300 consistently stimulated E2 production among patients with NOR, ARA, and PCOS. Recombinant FSH was the more potent ligand in GL cells from patients with NOR but was ineffective in cells from patients with ARA or PCOS. The lowest level of FSHR plasma membrane localization was seen in patients with ARA, although FSHR localization was more abundant in cells from patients with PCOS; the highest levels were present in cells from patients with NOR. The localization of FSHR was not affected by TOP5300 relative to rh-FSH in any patient group. TOP5300 stimulated greater expression of StAR and CYP19A1 across cells from all patients with NOR, ARA, and PCOS combined, although rh-FSH was unable to stimulate StAR and aromatase (CYP19A1) expression in cells from patients with PCOS. TOP5300-induced expression of StAR and CYP19A1 mRNA among patients with ARA and NOR was consistently lower than that observed in cells from patients with PCOS.
Conclusion(S):
TOP5300 appears to stimulate E2 production and steroidogenic gene expression from GL cells more than rh-FSH in PCOS, relative to patients with ARA and NOR. It does not appear that localization of FSHR at cell membranes is a limiting step for TOP5300 or rh-FSH stimulation of steroidogenic gene expression and E2 production.
More Related Videos
Related Concept Videos
Folliculogenesis
Target Cell Response to Hormones
Notably, the cellular response can be regulated by altering the number of receptors expressed in the cell. For example, prolonged exposure to elevated hormone levels results in a gradual decline or down-regulation in the number of receptors for that specific hormone on the cell surface. Conversely, in response to low hormone levels, cells may use up-regulation, producing an...
Hormonal Regulation of the Menstrual Cycle
At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH...
Hormonal Control of the Ovarian Cycle
Before puberty, the hypothalamus releases GnRH in a low frequency, low amplitude pulsatile manner. This along with the immature hypothalamic-pituitary-gonadal axis activity, results in low estrogen levels and the absence of a fully functional ovarian cycle. At puberty, GnRH secretion increases in both frequency and...


