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Badenhorst GD, Kannigadu C, Aucamp J, N'Da DD. Probing O-substituted Nifuroxazide analogues against Leishmania: Synthesis, in vitro efficacy, and hit/lead identification. Eur J Pharm Sci 2022; 176:106242. [PMID: 35732232 DOI: 10.1016/j.ejps.2022.106242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/07/2022] [Accepted: 06/18/2022] [Indexed: 11/03/2022]
Abstract
Leishmaniasis is a neglected tropical disease affecting millions of people worldwide, with 650 000 to 1.1 million new infections reported annually by the World Health Organization. Current antileishmanial treatments are unsatisfactory due to the development of parasitic resistance and the toxicity associated with the drugs used, and this highlights the need for the development of new antileishmanial drugs. In this study, a series of nifuroxazide analogues were synthesized in a single step reaction and investigated for their antileishmanial potential. The sulfonate 1l, bearing pyridine ring, was deemed an antileishmanial hit, targeting the amastigotes of Leishmania (L.) donovani and L. major, the pathogens of visceral and cutaneous leishmaniasis, respectively, with micromolar potencies. The benzyl analogues 2c and 2d were also confirmed as submicromolar active leads against amastigotes of L. major. These analogues stand as promising candidates for further investigation involving the evaluation of their in vivo activities and molecular targets.
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Affiliation(s)
- Gideon D Badenhorst
- School of Pharmacy, Faculty of Heath Sciences, North-West University, Potchefstroom 2520, South Africa
| | - Christina Kannigadu
- Drug Discovery, Centre of Excellence for Pharmaceutical Sciences, North-West University, Potchefstroom 2520, South Africa
| | - Janine Aucamp
- Drug Discovery, Centre of Excellence for Pharmaceutical Sciences, North-West University, Potchefstroom 2520, South Africa
| | - David D N'Da
- Drug Discovery, Centre of Excellence for Pharmaceutical Sciences, North-West University, Potchefstroom 2520, South Africa.
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2
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Kannigadu C, Aucamp J, N'Da DD. Synthesis and in vitro antileishmanial efficacy of benzyl analogues of nifuroxazide. Drug Dev Res 2020; 82:287-295. [PMID: 33141473 DOI: 10.1002/ddr.21755] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 10/12/2020] [Accepted: 10/16/2020] [Indexed: 12/22/2022]
Abstract
Leishmaniasis is a vector-borne parasitic disease that mostly affects populations in tropical and subtropical countries. There is currently no vaccine to protect against and only a handful of drugs are available to treat this disease. Leishmaniasis is curable, but its eradication and elimination are hindered by the emergence of multidrug resistant strains of the causative pathogens, accentuating the need for new and effective antileishmanial drugs. In search for such agents, nifuroxazide, a clinical antibiotic, was evaluated through investigation of its benzyl analogues for in vitro antileishmanial efficacy against promastigotes of various Leishmania (L.) strains. The monobenzylated analogues 1 and 2 were the most potent of all, possessing nanomolar activities up to 10-fold higher than the parent drug nifuroxazide against all three tested Leishmania strains. Both analogues stand as antipromastigote hits for further lead investigation into their potential to act as new antileishmanial agents.
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Affiliation(s)
- Christina Kannigadu
- Centre of Excellence for Pharmaceutical Sciences, North-West University, Potchefstroom, South Africa
| | - Janine Aucamp
- Centre of Excellence for Pharmaceutical Sciences, North-West University, Potchefstroom, South Africa
| | - David D N'Da
- Centre of Excellence for Pharmaceutical Sciences, North-West University, Potchefstroom, South Africa
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3
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Design and synthesis of novel 4-substituted 1,4-dihydropyridine derivatives as hypotensive agents. JOURNAL OF SAUDI CHEMICAL SOCIETY 2016. [DOI: 10.1016/j.jscs.2012.08.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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4
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Lin CF, Yang JS, Lin C, Tsai FJ, Lu CC, Lee MR. CCY-1a-E2 induces G2/M phase arrest and apoptotic cell death in HL-60 leukemia cells through cyclin-dependent kinase 1 signaling and the mitochondria-dependent caspase pathway. Oncol Rep 2016; 36:1633-9. [PMID: 27461132 DOI: 10.3892/or.2016.4970] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 04/22/2016] [Indexed: 11/05/2022] Open
Abstract
Our previous study demonstrated that 2-[(3-methoxybenzyl)oxy]benzaldehyde (CCY-1a-E2) is a potent compound that acts against multiple human leukemia cell lines. CCY-1a-E2 was also shown to have efficacious anti‑leukemic activity in vivo. However, the molecular mechanism of action of CCY‑1a‑E2 attributed to its anticancer effect remains poorly understood. In the present study, CCY‑1a‑E2 suppressed cell viability in multiple leukemia cell lines (HL‑60, K562, KG‑1 and KG‑1a) via inhibition of cell proliferation, cell cycle arrest and induction of apoptosis. CCY‑1a‑E2 exhibited a marked toxic effect on HL‑60 cells and displayed low cytotoxicity in normal human peripheral blood mononuclear cells (PBMCs). Results from flow cytometric analysis indicated that CCY‑1a‑E2 promoted G2/M phase arrest and promoted apoptosis in the HL‑60 cells. CCY‑1a‑E2 treatment upregulated cyclin B, cyclin‑dependent kinase 1 (CDK1), cell division cycle 25C (cdc25C) and p21 protein expression. CCY‑1a‑E2 caused apoptotic cell death and DNA fragmentation as determined by 4',6‑diamidino‑2‑phenylindole (DAPI) staining and DNA gel electrophoresis. Elevated activities of caspase‑8, ‑9 and ‑3 were observed during CCY‑1a‑E2‑induced cell apoptosis; their specific inhibitors were found to block CCY‑1a‑E2‑induced apoptosis, respectively. Moreover, CCY‑1a‑E2 time‑dependently disrupted the mitochondrial membrane potential (ΔΨm), and it enhanced the protein levels of Fas/CD95, cytochrome c, Bax, cleaved PARP, as well as attenuated Bcl‑2 expression in the HL‑60 cells. Our results provide direct evidence that supports the future potential therapeutic application of CCY-1a-E2 in leukemia.
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Affiliation(s)
- Chin-Fen Lin
- Department of Biochemistry, China Medical University, Taichung 404, Taiwan, R.O.C
| | - Jai-Sing Yang
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung 404, Taiwan, R.O.C
| | - Chingju Lin
- Department of Physiology, China Medical University, Taichung 404, Taiwan, R.O.C
| | - Fuu-Jen Tsai
- Human Genetic Center, China Medical University Hospital, Taichung 404, Taiwan, R.O.C
| | - Chi-Cheng Lu
- School of Nutrition and Health Sciences, Taipei Medical University, Taipei 110, Taiwan, R.O.C
| | - Miau-Rong Lee
- Department of Biochemistry, China Medical University, Taichung 404, Taiwan, R.O.C
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5
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Lv W, Banerjee B, Molland KL, Seleem MN, Ghafoor A, Hamed MI, Wan B, Franzblau SG, Mesecar AD, Cushman M. Synthesis of 3-(3-aryl-pyrrolidin-1-yl)-5-aryl-1,2,4-triazines that have antibacterial activity and also inhibit inorganic pyrophosphatase. Bioorg Med Chem 2014; 22:406-18. [PMID: 24315189 PMCID: PMC3914758 DOI: 10.1016/j.bmc.2013.11.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 10/23/2013] [Accepted: 11/05/2013] [Indexed: 11/26/2022]
Abstract
Inorganic pyrophosphatases are potential targets for the development of novel antibacterial agents. A pyrophosphatase-coupled high-throughput screening assay intended to detect o-succinyl benzoic acid coenzyme A (OSB CoA) synthetase inhibitors led to the unexpected discovery of a new series of novel inorganic pyrophosphatase inhibitors. Lead optimization studies resulted in a series of 3-(3-aryl-pyrrolidin-1-yl)-5-aryl-1,2,4-triazine derivatives that were prepared by an efficient synthetic pathway. One of the tetracyclic triazine analogues 22h displayed promising antibiotic activity against a wide variety of drug-resistant Staphylococcus aureus strains, as well as activity versus Mycobacterium tuberculosis and Bacillus anthracis, at a concentration that was not cytotoxic to mammalian cells.
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Affiliation(s)
- Wei Lv
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy and The Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN 47907, United States
| | - Biplab Banerjee
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy and The Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN 47907, United States
| | - Katrina L Molland
- Department of Biological Sciences and The Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN 47907, United States
| | - Mohamed N Seleem
- Department of Comparative Pathobiology, Purdue University College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, United States
| | - Adil Ghafoor
- Department of Comparative Pathobiology, Purdue University College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, United States
| | - Maha I Hamed
- Department of Comparative Pathobiology, Purdue University College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, United States
| | - Baojie Wan
- Institute for Tuberculosis Research, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, United States
| | - Scott G Franzblau
- Institute for Tuberculosis Research, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, United States
| | - Andrew D Mesecar
- Department of Biological Sciences and The Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN 47907, United States
| | - Mark Cushman
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy and The Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN 47907, United States.
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LIN CHINGJU, YANG JAISING, TSAI SHIHCHANG, LIN CHINFEN, LEE MIAURONG. In vivo evaluation of the synthesized novel 2-benzyloxybenzaldehyde analog CCY-1a-E2 for the treatment of leukemia in the BALB/c mouse WEHI-3 allograft model. Oncol Lett 2013; 5:777-782. [PMID: 23426190 PMCID: PMC3576184 DOI: 10.3892/ol.2012.1079] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Accepted: 11/29/2012] [Indexed: 12/01/2022] Open
Abstract
Our previous study demonstrated that the 2-benzyloxybenzaldehyde analog CCY-1a-E2 is a potent compound against HL-60 human leukemia cell lines. To investigate the potential therapeutic application of CCY-1a-E2 for leukemia, we analyzed the antileukemic effects and safety of CCY-1a-E2 in the BALB/c mouse WEHI-3 allograft model. Our results showed that CCY-1a-E2 decreased the percentage of viable cells in a concentration-dependent manner. The IC(50) of CCY-1a-E2 was 5 μM for the 24-h treatment of WEHI-3 cells. We examined the antileukemic activity of CCY-1a-E2 in the BALB/c mouse WEHI-3 allograft model. The CCY-1a-E2 (100 mg/kg) group was not found to have significantly decreased body weight compared with the control group, while the leukemia group was found to have significantly decreased body weight compared with the control mice. The CCY-1a-E2 (100 mg/kg) group showed no difference in spleen and liver weight, but significantly decreased levels of CD11b and CD45 compared with the leukemia group. In safety evaluation analysis, CCY-1a-E2 had no adverse effects on renal, hepatic and hematological parameters. Based on these observations, CCY-1a-E2 has efficacious antileukemic activity in the BALB/c mouse WEHI-3 allograft model.
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Affiliation(s)
- CHINGJU LIN
- Departments of Physiology, China Medical University, Taichung 40402, Taiwan,
R.O.C.
| | - JAI-SING YANG
- Pharmacology, China Medical University, Taichung 40402, Taiwan,
R.O.C.
| | - SHIH-CHANG TSAI
- Biological Science and Technology, China Medical University, Taichung 40402, Taiwan,
R.O.C.
| | - CHIN-FEN LIN
- Biochemistry, China Medical University, Taichung 40402, Taiwan,
R.O.C.
| | - MIAU-RONG LEE
- Biochemistry, China Medical University, Taichung 40402, Taiwan,
R.O.C.
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7
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Pavan B, Biondi C, Dalpiaz A. Adenylyl cyclases as innovative therapeutic goals. Drug Discov Today 2009; 14:982-91. [PMID: 19638320 DOI: 10.1016/j.drudis.2009.07.007] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 06/30/2009] [Accepted: 07/17/2009] [Indexed: 11/16/2022]
Abstract
Pharmacological modulation of intracellular cyclic AMP (cAMP) signalling could provide new therapeutic and experimental tools. Although drugs interfering with this pathway have traditionally targeted membrane receptors, the effector enzyme adenylyl cyclase (AC), which functions as a signalling catalyst, also presents an interesting target. Thus, development of isoform-selective stimulator and/or inhibitor compounds for AC could lead to organ-specific pharmacotherapeutics for treating heart failure, cancer and neurodegenerative diseases. In this review, the potential of AC as the object of drug therapy is discussed.
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Affiliation(s)
- Barbara Pavan
- Department of Biology and Evolution, General Physiology Section, University of Ferrara, Ferrara, Italy.
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Huang LJ, Wang JP, Lai YC, Kuo SC. Synthesis of (2E)-3-{2-[(substituted benzyl)oxy]phenyl}acrylaldehydes as novel anti-inflammatory agents. Bioorg Med Chem Lett 2006; 16:2742-7. [PMID: 16510283 DOI: 10.1016/j.bmcl.2006.02.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2005] [Revised: 01/28/2006] [Accepted: 02/06/2006] [Indexed: 11/12/2022]
Abstract
As part of our continuing effort for development of novel anti-inflammatory agents, the highly potential agent CCY1a, which we reported recently, was selected as lead compound to synthesize a series of its derivatives for evaluation. Most of the newly synthesized compounds exhibited superior inhibitory activity than both the lead compound and the positive control (trifluoperazine) toward fMLP-stimulated neutrophil superoxide formation. (2E)-3-[2-(Benzyloxy)-5-methoxyphenyl]-acrylaldehyde (31) was among the most potent with action mechanism different from CCY1a in that it does not act as cAMP-elevating agent but inhibits the increase in cellular Ca(2+) with greater potency.
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Affiliation(s)
- Li-Jiau Huang
- Graduate Institute of Pharmaceutical Chemistry, China Medical University, Taichung 40402, Taiwan, ROC.
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9
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Maloney DJ, Deng JZ, Starck SR, Gao Z, Hecht SM. (+)-Myristinin A, a Naturally Occurring DNA Polymerase β Inhibitor and Potent DNA-Damaging Agent. J Am Chem Soc 2005; 127:4140-1. [PMID: 15783174 DOI: 10.1021/ja042727j] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The first stereoselective total synthesis of the naturally occurring flavan myristinin A has been accomplished, as well as its biochemical evaluation. This synthesis verified the structural assignment and allowed for the determination of the absolute stereochemistry. Myristinin A exhibits biochemical activity both as a potent DNA-damaging agent and DNA polymerase beta inhibitor. Relaxation of supercoiled plasmid DNA was observed at picomolar concentrations, in addition to inhibition of polymerase beta at low micromolar concentrations.
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Affiliation(s)
- David J Maloney
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22901, USA
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Wang JP, Chang LC, Kuan YH, Tsao LT, Huang LJ, Kuo SC. 2-Benzyloxybenzaldehyde inhibits formyl peptide-stimulated increase in intracellular Ca2+ in neutrophils mainly by blocking Ca2+ entry. Naunyn Schmiedebergs Arch Pharmacol 2004; 370:353-60. [PMID: 15526104 DOI: 10.1007/s00210-004-0993-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2004] [Accepted: 09/24/2004] [Indexed: 10/26/2022]
Abstract
2-Benzyloxybenzaldehyde (CCY1a) inhibited the formyl-Met-Leu-Phe (fMLP)-induced elevation of cytosolic [Ca(2+)]() ([Ca(2+)](i)) in rat neutrophils. The late plateau phase, but not the initial Ca(2+) spike, of the fMLP-induced [Ca(2+)](i) change was inhibited by CCY1a. In the absence of external Ca(2+), CCY1a had no appreciable effect on either the fMLP- or cyclopiazonic acid (CPA)-induced [Ca(2+)](i) elevation. CCY1a failed to inhibit [Ca(2+)](i) changes induced by N-ethylmaleimide, GEA3162, ionomycin or sphingosine, but slightly inhibited the Ca(2+) signals elicited by ATP or interleukin-8 (IL-8). In a classical Ca(2+) readdition protocol, addition of CCY1a after cell activation strongly inhibited the [Ca(2+)](i) response to fMLP, whilst that to CPA was only slightly reduced. CCY1a nearly abrogated the fMLP-stimulated Mn(2+) influx but was less effective on the CPA-induced response. CCY1a attenuated the levels of tyrosine-phosphorylated bands in the 70-85 kDa molecular mass range. CCY1a had no effect on the basal [Ca(2+)](i) level, the pharmacologically isolated plasma membrane Ca(2+)-ATPase activity or on the mitochondrial membrane potential. Thus, CCY1a blocks fMLP-induced Ca(2+) entry into neutrophils probably by blocking the relevant Ca(2+) channel directly or, alternatively, indirectly through the attenuation of tyrosine phosphorylation of some cellular proteins.
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Affiliation(s)
- Jih-Pyang Wang
- Department of Education and Research, Taichung Veterans General Hospital, Taichung, Taiwan; Graduate Institute of Pharmaceutical Chemistry, China Medical University, Taichung, Taiwan, ROC.
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Wang JP, Chang LC, Lin YL, Hsu MF, Chang CY, Huang LJ, Kuo SC. Investigation of the cellular mechanism of inhibition of formyl-methionyl-leucyl-phenylalanine-induced superoxide anion generation in rat neutrophils by 2-benzyloxybenzaldehyde. Biochem Pharmacol 2003; 65:1043-51. [PMID: 12663040 DOI: 10.1016/s0006-2952(03)00006-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The inhibition of formyl-methionyl-leucyl-phenylalanine (fMLP)-induced superoxide anion (O2(.-)) generation by 2-benzyloxybenzaldehyde (CCY1a) was investigated in rat neutrophils, and the underlying mechanism of this inhibition was assessed. CCY1a concentration-dependently inhibited O2(.-) generation (IC(50)=18.5+/-4.3 microM). In cell-free systems, CCY1a failed to alter O2(.-) generation during dihydroxyfumaric acid autoxidation, in phorbol 12-myristate 13-acetate (PMA)-activated neutrophil particulate NADPH oxidase preparations, or during arachidonic acid-induced NADPH oxidase activation. CCY1a increased cellular cyclic AMP (cAMP) levels in a time- and concentration-dependent manner, and this cAMP-elevating effect was inhibited by the adenylyl cyclase inhibitor 9-(tetrahydro-2'-furyl)adenine (SQ22536), adenosine deaminase (ADA), and the adenosine receptor antagonist 8-(p-sulfophenyl)theophylline. In neutrophils, inhibition of O2(.-) generation by CCY1a was partially reversed by the protein kinase A inhibitor (9R,10S,12S)-2,3,9,10,11,12-hexahydro-10-hydroxy-9-methyl-1-oxo-9,12-epoxy-1H-diindolo[1,2,3-fg:3',2',1'-kl]pyrrolo[3,4-l][1,6]benzodiazocine-10-carboxylic acid, hexyl ester (KT5720). CCY1a did not affect fMLP-induced p38 mitogen-activated protein kinase phosphorylation, but concentration-dependently attenuated the phosphorylation of extracellular signal-regulated kinase (ERK) and Akt (IC(50) about 31.3 and 19.4 microM, respectively). The plateau phase, but not the initial spike, of fMLP-induced [Ca2+](i) changes was inhibited by CCY1a in a concentration-dependent manner. CCY1a inhibition of Ca2+ entry, ERK, and Akt phosphorylation was not prevented by SQ22536 or ADA. fMLP-induced phospholipase D (PLD) activation was inhibited by CCY1a (IC(50)=13.9+/-2.0 microM). ADA and KT5720 did not prevent the inhibition of PLD activation by CCY1a. Collectively, these results indicate that the inhibition by CCY1a of fMLP-induced O2(.-) generation in rat neutrophils can probably be attributed to the increase in cAMP levels, and to the blockade of Ca2+ entry, suppression of Akt, and PLD activation via cAMP-independent mechanisms.
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Affiliation(s)
- Jih-Pyang Wang
- Department of Education and Research, Taichung Veterans General Hospital, Taichung 407, Taiwan, Republic of China.
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Haunsø A, Simpson J, Antoni FA. Small ligands modulating the activity of mammalian adenylyl cyclases: a novel mode of inhibition by calmidazolium. Mol Pharmacol 2003; 63:624-31. [PMID: 12606770 DOI: 10.1124/mol.63.3.624] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Molecular cloning of membrane-spanning mammalian adenylyl cyclases (ACs) has led to the discovery of nine different isotypes, making ACs potentially useful therapeutic targets. This study investigated the mechanism by which fungicidal nitroimidazole compounds modulate AC activity. Current evidence indicates that biological control of AC activity occurs through the cytosolic domains. Hence, full-length ACII, ACIX, and recombinant fusion proteins composed of the cytoplasmic loops of human ACIX or the first and second cytoplasmic loops of rat ACV and ACII, respectively, were expressed in human embryonic kidney 293 cells. The AC activities of the respective proteins were characterized, and their modulation by nitroimidazoles was investigated. Calmidazolium inhibited the activities of both full-length ACs and soluble fusion proteins (IC(50), approximately 10 microM). Inhibition of ACIX by calmidazolium was mediated by direct interaction with the catalytic core in a noncompetitive fashion. ACIX was essentially insensitive to 2'-deoxyadenosine 3'-monophosphate, a known blocker of AC activity. The ACV-ACII fusion protein was inhibited by calmidazolium (IC(50), approximately 20 microM) as well as by 2'-deoxyadenosine 3'-AMP (IC(50), approximately 2 microM), in a manner indicating independent mechanisms of action. Taken together, the data demonstrate that ACIX is insensitive to adenosine analogs and that calmidazolium inhibits AC activity by a novel, noncompetitive mechanism.
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Affiliation(s)
- Anders Haunsø
- Department of Neuroscience, University of Edinburgh, Edinburgh, Scotland, United Kingdom.
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