Page 25 - PRECONGRESS COURSE 06

Key Points 1
 FSH is highly heterogeneous protein due to the presence of different sialylated Asn linked oligosaccharides which do cause the protein to be charged negatively. The higher the sialylation the more acidic the FSH isoform will be.
 The degree of sialylation impacts both the stability and biologic activity of the FSH isoform. Acidic (more highly sialylated) FSH isoforms are more stable (ie. have a longer half-life) than basic isoforms
 More acidic/sialylated analogues are more stable and therefore have a longer half life and do possess a greater potency for inducing synthesis of the -subunit mRNA of inhibin
 More basic FSH isoforms are more potent in stimulating oestrogen production and tPA enzyme activity whereas less acidic isoforms show an increased plasma clearance and decreased in vivo bioactivity
 Towards the end of a woman’s reproductive life span the acidic FSH isoforms increase whereas the basic isoforms decrease
 More basic FSH isoforms have higher binding affinity for the FSH receptor and have been associated with greater efficiency than acidic isoforms in promoting granulosa cell proliferation and rapid pre-antral follicular growth in vivo.
ESHRE PCC 6:
Ovarian Stimulation for IVF: Individualization and beyond:
The stimulation drug FSH: What do we need to know?
PHARMACODYNAMICS: COMPOSITION OF U-FSH VS. R-FSH
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PRECONGRESS COURSE 06 I GENEVA, SWITZERLAND – 2 JULY 2017 25