Abstract
We carried out a “pathway” screen of 50,000 small molecules to identify novel modulators of cAMP signaling. One class of compounds, the 2-(acylamino)-3-thiophenecarboxylates, strongly suppressed cAMP and cGMP in multiple cell lines in response to different agonists acting on G-protein-coupled receptors, adenylyl cyclase, and guanylyl cyclase. The best compounds from structure-activity analysis of 124 analogs, including several synthesized chiral analogs, had and IC50 of <5 μM for suppression of agonist-induced cAMP and cGMP elevation. Measurements of cAMP, cGMP, and downstream signaling in response to various activators/inhibitors suggested that the 2-(acylamino)-3-thiophenecarboxylates function as nonselective phosphodiesterase activators, although it was not determined whether their action on phosphodiesterases is direct or indirect. The 2-(acylamino)-3-thiophenecarboxylates suppressed CFTR-mediated Cl- current in T84 colonic cells in response to cholera and Escherichia coli (STa) toxins, and prevented intestinal fluid accumulation in a closed-loop mouse model of secretory diarrhea. They also prevented cyst growth in an in vitro renal epithelial cell model of polycystic kidney disease. The 2-(acylamino)-3-thiophenecarboxylates represent the first small-molecule cyclic nucleotide suppressors, whose potential therapeutic indications include secretory diarrheas, polycystic kidney disease, and growth inhibition of cAMP-dependent tumors.
Footnotes
-
This work was supported by grants DK72517, DK35124, HL59198, EY13574, EB00415, and HL73856 from the National Institutes of Health, and Research Development Program (R613) and Drug Discovery grants from the Cystic Fibrosis Foundation.
-
ABBREVIATIONS: PDE, phosphodiesterase; CFTR, cystic fibrosis transmembrane conductance regulator; V2R, vasopressin-V2 receptor; dDAVP, desmopressin; CTX, cholera toxin; STa, Escherichia coli heat-stable toxin; CPT, chlorophenylthio; IBMX, 3-isobutyl-1-methylxanthine; FRT, Fisher rat thyroid; YFP, yellow fluorescent protein; MDCK, Madin-Darby canine kidney; CHO, Chinese hamster ovary; PBS, phosphate-buffered saline; DMSO, dimethyl sulfoxide; ES-MS, electrospray mass spectroscopy; MRP, multidrug resistance protein; PDE, phosphodiesterase; CNT, cyclic nucleotide.
-
↵ The online version of this article (available at http://molpharm.aspetjournals.org) contains supplemental material.
- Received July 14, 2008.
- Accepted September 25, 2008.
- The American Society for Pharmacology and Experimental Therapeutics
MolPharm articles become freely available 12 months after publication, and remain freely available for 5 years.Non-open access articles that fall outside this five year window are available only to institutional subscribers and current ASPET members, or through the article purchase feature at the bottom of the page.
|