The human pituitary-derived heterodimeric glycoprotein hormones, follicle-stimulating hormone (FSH) and luteinising hormone (LH), are key hormones that play important roles in reproduction. FSH and LH consist of a common α-subunit and a hormone-specific β-subunit that can be differentially N-glycosylated. This gives rise to FSH and LH glycoforms that are either low or fully N-glycosylated, which has important functional consequences, affecting receptor binding and ultimately signal pathway activation. Hormone clearance rates determine how long hormones remain circulating and, ultimately, the bioactivity of the hormone.

Wide et al. therefore utilised gonadotrophin-releasing hormone (GnRH) blockade to estimate the clearance rates of endogenous human FSH and LH glycoforms. The results show that fully glycosylated FSH had a longer circulating half-life than low glycosylated FSH, with differences in the length of half-life depending on whether GnRH blockade was administered during the early follicular phase or mid-cycle. Interestingly, fully glycosylated FSH had a longer half circulating half-life than LH glycoforms, suggesting different functional roles of these glycoforms in modulating ovarian function.

Read the full article in Journal of Clinical Endocrinology & Metabolism doi: 10.1210/clinem/dgac434