Sterol metabolism controls T(H)17 differentiation by generating endogenous RORγ agonists.

Retinoic acid receptor-related orphan receptor γ (RORγt) controls the differentiation of naive CD4(+) T cells into the TH17 lineage, which are critical cells in the pathogenesis of autoimmune diseases. Here we report that during TH17 differentiation, cholesterol biosynthesis and uptake programs are induced, whereas their metabolism and efflux programs are suppressed. These changes result in the accumulation of the cholesterol precursor, desmosterol, which functions as a potent endogenous RORγ agonist. Generation of cholesterol precursors is essential for TH17 differentiation as blocking cholesterol synthesis with chemical inhibitors at steps before the formation of active precursors reduces differentiation. Upon activation, metabolic changes also lead to production of specific sterol-sulfate conjugates that favor activation of RORγ over the TH17-inhibiting sterol receptor LXR. Thus, TH17 differentiation is orchestrated by coordinated sterol synthesis, mobilization and metabolism to selectively activate RORγ.

Structure-based parallel medicinal chemistry approach to improve metabolic stability of benzopyran COX-2 inhibitors.

Combination of the structure-based design and solid-phase parallel synthesis provided an integrated approach to rapidly develop the structure-activity relationship of benzopyran COX-2 inhibitors. Binding free energies predicted by free energy perturbation theory yielded good agreement with experimental results. New potent and selective lead compounds with improved metabolic properties were identified.

Discovery of (3S,3aR)-2-(3-chloro-4-cyanophenyl)-3-cyclopentyl-3,3a,4,5-tetrahydro-2H-benzo[g]indazole-7-carboxylic acid (PF-3882845), an orally efficacious mineralocorticoid receptor (MR) antagonist for hypertension and nephropathy.

We have discovered a novel class of nonsteroidal pyrazoline antagonists of the mineralocorticoid receptor (MR) that show excellent potency and selectivity against other nuclear receptors. Early analogues were poorly soluble and had a propensity to inhibit the hERG channel. Remarkably, both of these challenges were overcome by incorporation of a single carboxylate moiety. Structural modification of carboxylate-containing lead R-4g with a wide range of substituents at each position of the pyrazoline ring resulted in R-12o, which shows excellent activity against MR and reasonable pharmacokinetic profile. Introduction of conformational restriction led to a novel series characterized by exquisite potency and favorable steroid receptor selectivity and pharmacokinetic profile. Oral dosing of 3S,3aR-27d (PF-3882845) in the Dahl salt sensitive preclinical model of salt-induced hypertension and nephropathy showed blood pressure attenuation significantly greater than that with eplerenone, reduction in urinary albumin, and renal protection. As a result of these findings, 3S,3aR-27d was advanced to clinical studies.

Biochemical, cellular, and anti-inflammatory properties of a potent, selective, orally bioavailable benzamide inhibitor of Rho kinase activity.

Rho kinase, is the most widely studied downstream effector of the small Rho GTPase RhoA. Two Rho kinase isoforms have been described and are frequently referred to in the literature as ROCK1 and ROCK2. The RhoA-Rho kinase pathway has been implicated in the recruitment of cellular infiltrates to disease loci in a number of preclinical animal models of inflammatory disease. In this study, we used biochemical enzyme assays and a cellular target biomarker assay to define PF-4950834 [N-methyl-3-{[(4-pyridin-4-ylbenzoyl)amino]methyl}benzamide] as an ATP-competitive, selective Rho kinase inhibitor. We further used PF-4950834 to study the role of Rho kinase activation in lymphocyte and neutrophil migration in addition to the endothelial cell-mediated expression of adhesion molecules and chemokines, which are essential for leukocyte recruitment. The inhibitor blocked stromal cell-derived factor-1alpha-mediated chemotaxis of T lymphocytes in vitro and the synthesis of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 in activated human endothelial cells in vitro. The secretion of chemokines interleukin-8 and monocyte chemoattractant protein-1 was also inhibited in activated endothelial cells. In addition, when dosed orally, the compound potently inhibited neutrophil migration in a carrageenan-induced acute inflammation model. In summary, we have used a pharmacologic approach to link Rho kinase activation to multiple phenotypes that can contribute to leukocyte infiltration. Inhibition of this pathway therefore could be strongly anti-inflammatory and provide therapeutic benefit in chronic inflammatory diseases.