Identification, synthesis, and biological evaluation of novel pyrazoles as low molecular weight luteinizing hormone receptor agonists.

In the course of a high throughput screening, a series of pyrazole compounds were identified with luteinizing hormone receptor (LH-R) agonist activity. A focused pyrazole library was produced by solid-phase synthesis and key pyrazole regioisomers were obtained selectively in solution. Evaluation of those compounds in a cAMP assay in CHO cells transfected with h-LH receptor allowed us to propose a structure-activity relationship model for this series and led to the identification of the first low molecular weight molecule with in vitro activity in a Leydig cells assay (ED(50)=1.31 microM) and in vivo in a model of testosterone induction in rats (significant effect at 32 mpk ip).

Formation of human IFN-beta complex with the soluble type I interferon receptor IFNAR-2 leads to enhanced IFN stability, pharmacokinetics, and antitumor activity in xenografted SCID mice.

Interferon-beta (IFN-beta) is biologically unstable under physiologic conditions in vitro and is cleared rapidly from the bloodstream on administration in vivo. In the present study, we demonstrate that a soluble recombinant form of the type I IFN receptor subunit, sIFNAR-2, can neutralize the bioactivity of type I IFNs at high concentrations and, at lower concentrations, causes an enhancement of IFN-beta-mediated antiviral activity. The in vitro enhancement is due to the specific interaction of IFN-beta with sIFNAR-2, followed by dissociation of IFN-beta from the complex over time in culture. In vivo, the serum half-life of IFN-beta is extended from minutes to hours when administered intravenously in mice as a sIFNAR-2-associated complex. Moreover, the antitumor effect of IFN-beta is increased by between 9-fold and 27-fold when injected as an sIFNAR-2-associated complex, as demonstrated by an increase in the mean survival time of immunodeficient mice challenged with human Burkitt lymphoma cell (Daudi) xenografts (sIFNAR-2-complexed vs. free IFN-beta treatment). These results show that on association with sIFNAR-2, IFN-beta is more stable in vitro and exhibits increased efficacy when administered in vivo. Administration as a complex with sIFNAR-2 may, therefore, provide a method of enhancing the delivery and effectiveness of type I IFNs.

FSH beta gene mutations in a female with partial breast development and a male sibling with normal puberty and azoospermia.

FSH is a dimeric pituitary glycoprotein hormone that regulates gonadal function. Human mutations in the FSH beta gene have been shown to produce complete deficiency states in which pubertal development and reproductive capacity are inhibited. To date, no patients with partial or complete pubertal development due to FSH beta mutations have been documented in humans. We describe and characterize affected siblings, a male and a female, with evidence of pubertal development due to homozygosity for a Tyr76X nonsense mutation in the FSH beta gene. In vitro analysis of this mutant demonstrates unmeasurable FSH by immunoassay and by two different bioassays, using either cAMP (homologous FSH bioassay) or estradiol (rat granulosa cell assay) as the endpoints. In additional in vitro analyses, mutants previously found in patients with a phenotype of complete FSH deficiency (Cys51Gly and Val61X) and the Tyr76X were compared in the same immuno- and bioassays. All mutations failed to produce measurable FSH by all assays. Unexpectedly, these siblings with isolated FSH deficiency due to a nonsense FSH beta mutation had some evidence of puberty, suggesting that other factors might preserve gonadal steroidogenesis in the absence of FSH or that current bioassays cannot discriminate among very low FSH levels.