cv-1808 and Inflammation

Chronic obstructive pulmonary disease (COPD) is a neutrophilic inflammatory disorder that is weakly responsive to glucocorticoids. Identification of ways to enhance the anti-inflammatory activity of glucocorticoids is, therefore, a major research objective. Adenosine receptor agonists that target the A2B-receptor subtype are efficacious in several cell-based assays and preclinical models of inflammation. Accordingly, the present study was designed to determine if a selective A2B-receptor agonist, 2-[6-amino-3,5-dicyano-4-[4-(cyclopropylmethoxy)phenyl]pyridin-2-ylsulphanyl]acetamide (Bay 60-6583), and a glucocorticoid, dexamethasone, in combination display putative anti-inflammatory activity that is superior to either drug alone. In BEAS-2B human airway epithelial cells stably transfected with cAMP-response element (CRE) and glucocorticoid response element (GRE) reporter constructs, Bay 60-6583 promoted CRE-dependent transcription and enhanced GRE-dependent transcription by an adenosine A2B-receptor-mediated mechanism that was associated with cAMP formation and abolished by an inhibitor of cAMP-dependent protein kinase. Analysis of the concentration-response relationship that described the enhancement of GRE-dependent transcription showed that Bay 60-6583 increased the magnitude of response without affecting the potency of dexamethasone. Bay 60-6583 and dexamethasone also induced a panel of genes that, collectively, could have benefit in COPD. These were categorized into genes that were induced in a positive cooperative manner (RGS2, p57(kip2)), an additive manner (TTP, BRL-1), or by Bay 60-6583 (CD200, CRISPLD2, SOCS3) or dexamethasone (GILZ) only. Thus, the gene induction "fingerprints" produced by Bay 60-6583 and dexamethasone, alone and in combination, were distinct. Collectively, through their actions on gene expression, an adenosine A2B-receptor agonist and a glucocorticoid administered together may have utility in the treatment of inflammatory disorders that respond suboptimally to glucocorticoids as a monotherapy.

Topics: Adenosine; Adenosine A2 Receptor Agonists; Algorithms; Aminopyridines; Calcium; Cell Line; Cyclic AMP; Cyclic AMP Response Element Modulator; Cytosol; Dexamethasone; Epithelial Cells; Humans; Inflammation; Phenethylamines; Pulmonary Disease, Chronic Obstructive; Real-Time Polymerase Chain Reaction; Receptor, Adenosine A2B; Receptors, Glucocorticoid; Respiratory Mucosa; RNA, Messenger; Transfection

This protocol describes microsphere-based protease assays for use in flow cytometry and high-throughput screening. This platform measures a loss of fluorescence from the surface of a microsphere due to the cleavage of an attached fluorescent protease substrate by a suitable protease enzyme. The assay format can be adapted to any site or protein-specific protease of interest and results can be measured in both real time and as endpoint fluorescence assays on a flow cytometer. Endpoint assays are easily adapted to microplate format for flow cytometry high-throughput analysis and inhibitor screening.

Topics: Animals; Biotinylation; Flow Cytometry; Fluorescence Resonance Energy Transfer; Green Fluorescent Proteins; High-Throughput Screening Assays; Humans; Inflammation; Kinetics; Microspheres; Peptide Hydrolases; Peptides; Reproducibility of Results; Temperature