Dataset Information

A2B adenosine receptor inhibition by the dihydropyridine calcium channel blocker nifedipine involves colonic fluid secretion.

ABSTRACT: The adenosine A2B receptor is a critical protein in intestinal water secretion. In the present study, we screened compound libraries to identify inhibitors of the A2B receptor and evaluated their effect on adenosine-induced intestinal fluid secretion. The screening identified the dihydropyridine calcium antagonists nifedipine and nisoldipine. Their respective affinities for the A2B receptor (Ki value) were 886 and 1,399?nM. Nifedipine and nisoldipine, but not amlodipine or nitrendipine, inhibited both calcium mobilization and adenosine-induced cAMP accumulation in cell lines. Moreover, adenosine injection into the lumen significantly increased fluid volume in the colonic loop of wild-type mice but not A2B receptor-deficient mice. PSB-1115, a selective A2B receptor antagonist, and nifedipine prevented elevated adenosine-stimulated fluid secretion in mice. Our results may provide useful insights into the structure-activity relationship of dihydropyridines for A2B receptor. As colonic fluid secretion by adenosine seems to rely predominantly on the A2B receptor, nifedipine could be a therapeutic candidate for diarrhoea-related diseases.

SUBMITTER: Asano T

PROVIDER: S-EPMC7044278 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

A2B adenosine receptor inhibition by the dihydropyridine calcium channel blocker nifedipine involves colonic fluid secretion.

Asano Teita T Noda Yuto Y Tanaka Ken-Ichiro KI Yamakawa Naoki N Wada Mitsuhito M Mashimo Tadaaki T Fukunishi Yoshifumi Y Mizushima Tohru T Takenaga Mitsuko M

Scientific reports 20200226 1

The adenosine A2B receptor is a critical protein in intestinal water secretion. In the present study, we screened compound libraries to identify inhibitors of the A2B receptor and evaluated their effect on adenosine-induced intestinal fluid secretion. The screening identified the dihydropyridine calcium antagonists nifedipine and nisoldipine. Their respective affinities for the A2B receptor (Ki value) were 886 and 1,399 nM. Nifedipine and nisoldipine, ...[more]

PMID: 32103051

Similar Datasets

Project description:c-Kit+ progenitor smooth muscle cells (P-SMCs) can develop into SMCs that contribute to injury-induced neointimal thickening. Here, we investigated whether adenosine reduces P-SMC migration and proliferation and whether this contributes to adenosine's inhibitory actions on neointima formation. In human P-SMCs, 2-chloroadenosine (stable adenosine analogue) and BAY60-6583 (A2B agonist) inhibited P-SMC proliferation and migration. Likewise, increasing endogenous adenosine by blocking adenosine metabolism with erythro-9-(2-hydroxy-3-nonyl) adenine (inhibits adenosine deaminase) and 5-iodotubercidin (inhibits adenosine kinase) attenuated P-SMC proliferation and migration. Neither N6-cyclopentyladenosine (A1 agonist), CGS21680 (A2A agonist), nor N6-(3-iodobenzyl)-adenosine-5'-N-methyluronamide (A3 agonist) affected P-SMC proliferation or migration. 2-Chloroadenosine increased cyclic AMP, reduced Akt phosphorylation (activates cyclin D expression), and reduced levels of cyclin D1 (promotes cell-cycle progression). Moreover, 2-chloroadenosine inhibited expression of Skp2 (promotes proteolysis of p27Kip1) and upregulated levels of p27Kip1 (negative cell-cycle regulator). A2B receptor knockdown prevented the effects of 2-chloroadenosine on cyclic AMP production and P-SMC proliferation and migration. Likewise, inhibition of adenylyl cyclase and protein kinase A rescued P-SMCs from the inhibitory effects of 2-chloroadenosine. The inhibitory effects of adenosine were similar in male and female P-SMCs. In vivo, peri-arterial (rat carotid artery) 2-chloroadenosine (20 ?mol/L for 7 days) reduced neointimal hyperplasia by 64.5% (P<0.05; intima/media ratio: control, 1.4±0.02; treated, 0.53±0.012) and reduced neointimal c-Kit+ cells. Adenosine inhibits P-SMC migration and proliferation via the A2B receptor/cyclic AMP/protein kinase A axis, which reduces cyclin D1 expression and activity via inhibiting Akt phosphorylation and Skp2 expression and upregulating p27kip1 levels. Adenosine attenuates neointima formation in part by inhibiting infiltration and proliferation of c-Kit+ P-SMCs.

Dataset Information

A2B adenosine receptor inhibition by the dihydropyridine calcium channel blocker nifedipine involves colonic fluid secretion.

Publications

A<sub>2B</sub> adenosine receptor inhibition by the dihydropyridine calcium channel blocker nifedipine involves colonic fluid secretion.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure