Modification of the carbohydrate content of hFSH has significant effect on the physiologic properties of the hormone in vivo. To date, preliminary characterization of one such modification has been investigated: hFSH tethered to the CTP from the beta-subunit of hCG (either as a single-chain peptide or as a dimer associated with alpha-subunit). This modification increases the half-life and in vivo bioactivity of the hormone. The effect of fewer or greater numbers of O-linked carbohydrates, the impact on spacing of these moieties, and the potential role of N-linked sugars in this capacity have yet to be thoroughly investigated. These studies will generate important data as to general principles for carbohydrate physiology. By defining the role of differential glycosylation, therapeutic derivatives may be developed through carbohydrate manipulations that may be applicable to all the glycoprotein hormones as well as recombinant proteins in general. In addition, we have preliminary data indicating the feasibility of producing bifunctional hFSH analogues consisting of hFSH tethered to a growth factor. Bifunctionality, both in vitro and in vivo at the level of the ovary was confirmed. This allows for continued and expanded studies on the role of various targeted growth factors on ovarian physiology. Synergistic action on follicular development may also have therapeutic implications for women requiring ovarian stimulation for infertility. Structural knowledge of the interface between FSH and its receptor is essential to developing methods to perturb receptor activity. We plan to determine the structure of the extracellular domain (ECD) of the hFSH receptor, a member of the G protein- coupled receptor superfamily. A three-dimensional representation of the binding region of a glycoprotein hormone receptor will be elucidated for the first time. The structural dynamics and conformational changes in the receptor following ligand binding will provide data crucial to our understanding of the conditions requisite for receptor activation. Together, the studies described in this application will greatly enhance our understanding of gonadotropin biology, the role of various cofactors in ovarian physiology and elicit new methods for altering pharmacodynamics and pharmacokinetics of recombinant proteins.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK063224-02
Application #
6838141
Study Section
Reproductive Biology Study Section (REB)
Program Officer
Malozowski, Saul N
Project Start
2004-01-01
Project End
2008-12-31
Budget Start
2005-01-01
Budget End
2005-12-31
Support Year
2
Fiscal Year
2005
Total Cost
$384,225
Indirect Cost
Name
Columbia University (N.Y.)
Department
Obstetrics & Gynecology
Type
Schools of Medicine
DUNS #
621889815
City
New York
State
NY
Country
United States
Zip Code
10032
Trousdale, Rhonda K; Jacobs, Sharone'; Simhaee, David A et al. (2009) Wound closure and metabolic parameter variability in a db/db mouse model for diabetic ulcers. J Surg Res 151:100-7
Vardhana, Pratibhasri A; Julius, Martin A; Pollak, Susan V et al. (2009) A unique human chorionic gonadotropin antagonist suppresses ovarian hyperstimulation syndrome in rats. Endocrinology 150:3807-14
Wang, Jeff; Dicken, Cary; Lustbader, Joyce W et al. (2009) Evidence for a Mullerian-inhibiting substance autocrine/paracrine system in adult human endometrium. Fertil Steril 91:1195-203
Sanders, Rebecca D; Spencer, Jessica B; Epstein, Michael P et al. (2009) Biomarkers of ovarian function in girls and women with classic galactosemia. Fertil Steril 92:344-51
Trousdale, Rhonda K; Yu, Bo; Pollak, Susan V et al. (2009) Efficacy of native and hyperglycosylated follicle-stimulating hormone analogs for promoting fertility in female mice. Fertil Steril 91:265-70
Trousdale, Rhonda K; Pollak, Susan V; Klein, Jeffrey et al. (2007) Single-chain bifunctional vascular endothelial growth factor (VEGF)-follicle-stimulating hormone (FSH)-C-terminal peptide (CTP) is superior to the combination therapy of recombinant VEGF plus FSH-CTP in stimulating angiogenesis during ovarian folliculogen Endocrinology 148:1296-305
Ruman, Jane I; Pollak, Susan; Trousdale, Rhonda K et al. (2005) Effects of long-acting recombinant human follicle-stimulating hormone analogs containing N-linked glycosylation on murine folliculogenesis. Fertil Steril 83 Suppl 1:1303-9
Weenen, C; Pena, J E; Pollak, S V et al. (2004) Long-acting follicle-stimulating hormone analogs containing N-linked glycosylation exhibited increased bioactivity compared with o-linked analogs in female rats. J Clin Endocrinol Metab 89:5204-12