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Paul D, Agrawal R, Singh S. Alzheimer's disease and clinical trials. J Basic Clin Physiol Pharmacol 2024; 35:31-44. [PMID: 38491747 DOI: 10.1515/jbcpp-2023-0264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 02/28/2024] [Indexed: 03/18/2024]
Abstract
Alzheimer's disease (AD) is spreading its root disproportionately among the worldwide population. Many genes have been identified as the hallmarks of AD. Based upon the knowledge, many clinical trials have been designed and conducted. Attempts have been made to alleviate the pathology associated with AD by targeting the molecular products of these genes. Irrespective of the understanding on the genetic component of AD, many clinical trials have failed and imposed greater challenges on the path of drug discovery. Therefore, this review aims to identify research and review articles to pinpoint the limitations of drug candidates (thiethylperazine, CT1812, crenezumab, CNP520, and lecanemab), which are under or withdrawn from clinical trials. Thorough analysis of the cross-talk pathways led to the identification of many confounding factors, which could interfere with the success of clinical trials with drug candidates such as thiethylperazine, CT1812, crenezumab, and CNP520. Though these drug candidates were enrolled in clinical trials, yet literature review shows many limitations. These limitations raise many questions on the rationale behind the enrollments of these drug candidates in clinical trials. A meticulous prior assessment of the outcome of clinical studies may stop risky clinical trials at their inceptions. This may save time, money, and resources.
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Affiliation(s)
- Deepraj Paul
- Department of Pharmacology, 621320 College of Pharmacy JSS Academy of Technical Education , Noida, Uttar Pradesh, India
| | - Rohini Agrawal
- Department of Pharmacology, 621320 College of Pharmacy JSS Academy of Technical Education , Noida, Uttar Pradesh, India
| | - Swati Singh
- Department of Pharmacology, 621320 College of Pharmacy JSS Academy of Technical Education , Noida, Uttar Pradesh, India
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2
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Woo S, Shenvi RA. Synthesis and target annotation of the alkaloid GB18. Nature 2022; 606:917-921. [PMID: 35551513 PMCID: PMC10036212 DOI: 10.1038/s41586-022-04840-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 05/06/2022] [Indexed: 11/08/2022]
Abstract
Ingestion of alkaloid metabolites from the bark of Galbulimima (GB) sp. leads to psychotropic and excitatory effects in humans1-4. Limited, variable supply of GB alkaloids5, however, has impeded their biological exploration and clinical development6. Here we report a solution to the supply of GB18, a structural outlier and putative psychotropic principle of Galbulimima bark. Efficient access to its challenging tetrahedral attached-ring motif required the development of a ligand-controlled endo-selective cross-electrophile coupling and a diastereoselective hydrogenation of a rotationally dynamic pyridine. Reliable, gram-scale access to GB18 enabled its assignment as a potent antagonist of κ- and μ-opioid receptors-the first new targets in 35 years-and lays the foundation to navigate and understand the biological activity of Galbulimima metabolites.
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Affiliation(s)
- Stone Woo
- Department of Chemistry, Scripps Research, La Jolla, CA, USA
| | - Ryan A Shenvi
- Department of Chemistry, Scripps Research, La Jolla, CA, USA.
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3
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Wysocka A, Palasz E, Steczkowska M, Niewiadomska G. Dangerous Liaisons: Tau Interaction with Muscarinic Receptors. Curr Alzheimer Res 2021; 17:224-237. [PMID: 32329686 PMCID: PMC7509759 DOI: 10.2174/1567205017666200424134311] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 02/05/2020] [Accepted: 03/25/2020] [Indexed: 11/22/2022]
Abstract
The molecular processes underlying neurodegenerative diseases (such as Alzheimer's Disease - AD) remain poorly understood. There is also an imperative need for disease-modifying therapies in AD since the present treatments, acetylcholinesterase inhibitors and NMDA antagonists, do not halt its progression. AD and other dementias present unique pathological features such as that of microtubule associated protein tau metabolic regulation. Tau has numerous binding partners, including signaling molecules, cytoskeletal elements and lipids, which suggests that it is a multifunctional protein. AD has also been associated with severe loss of cholinergic markers in the brain and such loss may be due to the toxic interaction of tau with cholinergic muscarinic receptors. By using specific antagonists of muscarinic receptors it was found in vitro that extracellular tau binds to M1 and M3 receptors and which the increase of intracellular calcium found in neuronal cells upon tau-binding. However, so far, the significance of tau signaling through muscarinic receptor in vivo in tauopathic models remains uncertain. The data reviewed in the present paper highlight the significant effect of M1 receptor/tau interaction in exacerbating tauopathy related pathological features and suggest that selective M1 agonists may serve as a prototype for future therapeutic development toward modification of currently intractable neurodegenerative diseases, such as tauopathies.
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Affiliation(s)
- Adrianna Wysocka
- Neurobiology Center, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland
| | - Ewelina Palasz
- Department of Applied Physiology, Mossakowski Medical Research Center, 02-093 Warsaw, Poland
| | - Marta Steczkowska
- Department of Applied Physiology, Mossakowski Medical Research Center, 02-093 Warsaw, Poland
| | - Grazyna Niewiadomska
- Neurobiology Center, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland
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4
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Weinhart CG, Wifling D, Schmidt MF, Neu E, Höring C, Clark T, Gmeiner P, Keller M. Dibenzodiazepinone-type muscarinic receptor antagonists conjugated to basic peptides: Impact of the linker moiety and unnatural amino acids on M 2R selectivity. Eur J Med Chem 2021; 213:113159. [PMID: 33571911 DOI: 10.1016/j.ejmech.2021.113159] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 01/03/2021] [Accepted: 01/04/2021] [Indexed: 10/22/2022]
Abstract
The family of human muscarinic acetylcholine receptors (MRs) is characterized by a high sequence homology among the five subtypes (M1R-M5R), being the reason for a lack of subtype selective MR ligands. In continuation of our work on dualsteric dibenzodiazepinone-type M2R antagonists, a series of M2R ligands containing a dibenzodiazepinone pharmacophore linked to small basic peptides was synthesized (64 compounds). The linker moiety was varied with respect to length, number of basic nitrogens (0-2) and flexibility. Besides proteinogenic basic amino acids (Lys, Arg), shorter homologues of Lys and Arg, containing three and two methylene groups, respectively, as well as D-configured amino acids were incorporated. The type of linker had a marked impact on M2R affinity and also effected M2R selectivity. In contrast, the structure of the basic peptide rather determined M2R selectivity than M2R affinity. For example, the most M2R selective compound (UR-CG188, 89) with picomolar M2R affinity (pKi 9.60), exhibited a higher M2R selectivity (ratio of Ki M1R/M2R/M3R/M4R/M5R: 110:1:5200:55:2300) compared to the vast majority of reported M2R preferring MR ligands. For selected ligands, M2R antagonism was confirmed in a M2R miniG protein recruitment assay.
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Affiliation(s)
- Corinna G Weinhart
- Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053, Regensburg, Germany
| | - David Wifling
- Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053, Regensburg, Germany
| | - Maximilian F Schmidt
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich Alexander University Erlangen-Nürnberg, Nikolaus-Fiebiger-Straße 10, D-91058, Erlangen, Germany; Department of Chemistry and Pharmacy, Computer-Chemistry-Center, Friedrich Alexander University Erlangen-Nürnberg, Nägelsbachstrasse 25, D-91052, Erlangen, Germany
| | - Eduard Neu
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich Alexander University Erlangen-Nürnberg, Nikolaus-Fiebiger-Straße 10, D-91058, Erlangen, Germany; Department of Chemistry and Pharmacy, Computer-Chemistry-Center, Friedrich Alexander University Erlangen-Nürnberg, Nägelsbachstrasse 25, D-91052, Erlangen, Germany
| | - Carina Höring
- Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053, Regensburg, Germany
| | - Timothy Clark
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich Alexander University Erlangen-Nürnberg, Nikolaus-Fiebiger-Straße 10, D-91058, Erlangen, Germany; Department of Chemistry and Pharmacy, Computer-Chemistry-Center, Friedrich Alexander University Erlangen-Nürnberg, Nägelsbachstrasse 25, D-91052, Erlangen, Germany
| | - Peter Gmeiner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich Alexander University Erlangen-Nürnberg, Nikolaus-Fiebiger-Straße 10, D-91058, Erlangen, Germany
| | - Max Keller
- Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053, Regensburg, Germany.
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5
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Pegoli A, Wifling D, Gruber CG, She X, Hübner H, Bernhardt G, Gmeiner P, Keller M. Conjugation of Short Peptides to Dibenzodiazepinone-Type Muscarinic Acetylcholine Receptor Ligands Determines M2R Selectivity. J Med Chem 2019; 62:5358-5369. [PMID: 31074983 DOI: 10.1021/acs.jmedchem.8b01967] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Andrea Pegoli
- Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - David Wifling
- Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Corinna G. Gruber
- Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Xueke She
- Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Harald Hübner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich Alexander University, Nikolaus-Fiebiger-Straße 10, D-91058 Erlangen, Germany
| | - Günther Bernhardt
- Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Peter Gmeiner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich Alexander University, Nikolaus-Fiebiger-Straße 10, D-91058 Erlangen, Germany
| | - Max Keller
- Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
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6
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Lipase-catalyzed asymmetric synthesis of naphtho[2,3-c]furan-1(3H)-one derivatives by a one-pot dynamic kinetic resolution/intramolecular Diels–Alder reaction: Total synthesis of (−)-himbacine. Bioorg Med Chem 2018; 26:1378-1386. [DOI: 10.1016/j.bmc.2017.08.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 08/09/2017] [Accepted: 08/10/2017] [Indexed: 10/19/2022]
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7
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Pegoli A, She X, Wifling D, Hübner H, Bernhardt G, Gmeiner P, Keller M. Radiolabeled Dibenzodiazepinone-Type Antagonists Give Evidence of Dualsteric Binding at the M2 Muscarinic Acetylcholine Receptor. J Med Chem 2017; 60:3314-3334. [PMID: 28388054 DOI: 10.1021/acs.jmedchem.6b01892] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Andrea Pegoli
- Institute
of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Xueke She
- Institute
of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - David Wifling
- Institute
of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Harald Hübner
- Department
of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University, Schuhstrasse 19, D-91052 Erlangen, Germany
| | - Günther Bernhardt
- Institute
of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Peter Gmeiner
- Department
of Chemistry and Pharmacy, Emil Fischer Center, Friedrich Alexander University, Schuhstrasse 19, D-91052 Erlangen, Germany
| | - Max Keller
- Institute
of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
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8
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Design and synthesis of N-[6-(Substituted Aminoethylideneamino)-2-Hydroxyindan-1-yl]arylamides as selective and potent muscarinic M1 agonists. Bioorg Med Chem Lett 2015; 25:4158-63. [DOI: 10.1016/j.bmcl.2015.08.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 08/01/2015] [Accepted: 08/06/2015] [Indexed: 01/16/2023]
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9
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Keller M, Tränkle C, She X, Pegoli A, Bernhardt G, Buschauer A, Read RW. M2 Subtype preferring dibenzodiazepinone-type muscarinic receptor ligands: Effect of chemical homo-dimerization on orthosteric (and allosteric?) binding. Bioorg Med Chem 2015; 23:3970-90. [PMID: 25650309 DOI: 10.1016/j.bmc.2015.01.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 12/21/2014] [Accepted: 01/07/2015] [Indexed: 10/24/2022]
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10
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Muscarinic acetylcholine receptor modulators derived from natural toxins and diverse interaction modes. Sci China Chem 2013. [DOI: 10.1007/s11426-013-4958-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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11
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Abstract
The physiological role of muscarinic receptors is highly complex and, although not completely understood, has become clearer over the last decade. Recent pharmacological evidence with novel compounds, together with data from transgenic mice, suggests that all five subtypes have defined functions in the nervous system as well as mediating the non neuronal, hormonal actions of acetylcholine. Numerous novel agonists, allosteric regulators, and antagonists have now been identified with authentic subtype specificity in vitro and in vivo. These compounds provide additional pharmacological opportunities for selective subtype modulation as well as a new generation of muscarinic receptor-based therapeutics.
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Affiliation(s)
- Richard M Eglen
- Corning Life Sciences, 900 Chelmsford St., MA 01851, Lowell, USA.
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12
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Fisher A. Cholinergic modulation of amyloid precursor protein processing with emphasis on M1 muscarinic receptor: perspectives and challenges in treatment of Alzheimer’s disease. J Neurochem 2011; 120 Suppl 1:22-33. [DOI: 10.1111/j.1471-4159.2011.07507.x] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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13
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Fisher A. Cholinergic treatments with emphasis on m1 muscarinic agonists as potential disease-modifying agents for Alzheimer's disease. Neurotherapeutics 2008; 5:433-42. [PMID: 18625455 PMCID: PMC5084245 DOI: 10.1016/j.nurt.2008.05.002] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The only prescribed drugs for treatment of Alzheimer's disease (AD) are acetylcholinesterase inhibitors (e.g., donepezil, rivastigmine, galantamine, and tacrine) and memantine, an NMDA antagonist. These drugs ameliorate mainly the symptoms of AD, such as cognitive impairments, rather than halting or preventing the causal neuropathology. There is currently no cure for AD and there is no way to stop its progression, yet there are numerous therapeutic approaches directed against various pathological hallmarks of AD that are extensively being pursued. In this context, the three major hallmark characteristics of AD (i.e., the CNS cholinergic hypofunction, formation of beta-amyloid plaques, and tangles containing hyperphosphorylated tau proteins) are apparently linked. Such linkages may have therapeutic implications, and this review is an attempt to analyze these versus the advantages and drawbacks of some cholinergic compounds, such as acetylcholinesterase inhibitors, M1 muscarinic agonists, M2 antagonists, and nicotinic agonists. Among the reviewed treatments, M1 selective agonists emerge, in particular, as potential disease modifiers.
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Affiliation(s)
- Abraham Fisher
- Israel Institute for Biological Research, PO Box 19, Ness-Ziona, Israel.
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14
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Tumiatti V, Minarini A, Milelli A, Rosini M, Buccioni M, Marucci G, Ghelardini C, Bellucci C, Melchiorre C. Structure–activity relationships of methoctramine-related polyamines as muscarinic antagonist: Effect of replacing the inner polymethylene chain with cyclic moieties. Bioorg Med Chem 2007; 15:2312-21. [PMID: 17276075 DOI: 10.1016/j.bmc.2007.01.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Revised: 01/08/2007] [Accepted: 01/17/2007] [Indexed: 11/21/2022]
Abstract
The aim of the present paper was to investigate the role of the octamethylene spacer of methoctramine (1) on the biological profile. Thus, this spacer was incorporated into a dianiline or dipiperidine moiety to determine whether flexibility and the basicity of the inner nitrogen atoms are important determinants of potency with respect to muscarinic receptors. The most potent compound was 4, which displayed, in the functional assays, a comparable potency at muscarinic M(2) receptors with respect to 1, and, in the binding assays, a loss of potency and selectivity toward muscarinic M(1) and M(3) receptor subtypes. Both compounds were endowed with antinociceptive activity. Furthermore, in microdialysis tests in rat parietal cortex, they enhanced acetylcholine release, most likely by antagonizing presynaptic muscarinic receptor subtypes.
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Affiliation(s)
- Vincenzo Tumiatti
- Dipartimento di Scienze Farmaceutiche, Università di Bologna, Via Belmeloro 6, 40126 Bologna, Italy.
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15
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Romanelli MN, Galeotti N, Ghelardini C, Manetti D, Martini E, Gualtieri F. Pharmacological characterization of DM232 (unifiram) and DM235 (sunifiram), new potent cognition enhancers. CNS DRUG REVIEWS 2006; 12:39-52. [PMID: 16834757 PMCID: PMC6741768 DOI: 10.1111/j.1527-3458.2006.00039.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
DM232 (unifiram) and DM235 (sunifiram) are potent cognition-enhancers, which are four order of magnitude more potent than piracetam. These compounds, although not showing affinity in binding studies for the most important central receptors or channels, are able to prevent amnesia induced by modulation of several neurotransmission systems. These compounds are able to increase the release of acetylcholine from rat cerebral cortex, and, as far as unifiram is concerned, to increase the amplitude of fEPSP in rat hippocampal slices. In vitro experiments, performed on hippocampal slices, also supported the hypothesis of a role of the AMPA receptors for the cognition-enhancing properties of unifiram and sunifiram.
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Affiliation(s)
- M N Romanelli
- Dipartimento di Scienze Farmaceutiche, University of Florence, Sesto Fiorentino, Italy.
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16
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Eglen RM. Muscarinic receptor subtypes in neuronal and non-neuronal cholinergic function. AUTONOMIC & AUTACOID PHARMACOLOGY 2006; 26:219-33. [PMID: 16879488 DOI: 10.1111/j.1474-8673.2006.00368.x] [Citation(s) in RCA: 212] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
1 Muscarinic M1-M5 receptors mediate the metabotropic actions of acetylcholine in the nervous system. A growing body of data indicate they also mediate autocrine functions of the molecule. The availability of novel and selective muscarinic agonists and antagonists, as well as in vivo gene disruption techniques, has clarified the roles of muscarinic receptors in mediating both functions of acetylcholine. 2 Selective M1 agonists or mixed M1 agonists/M2 antagonists may provide an approach to the treatment of cognitive disorders, while M3 antagonism, or mixed M2/M3 antagonists, are approved for the treatment of contractility disorders including overactive bladder and chronic obstructive pulmonary disease. Preclinical data suggest that selective agonism of the M4 receptor will provide novel anti-nociceptive agents, while therapeutics-based upon agonism or antagonism of the muscarinic M5 receptor have yet to be reported. 3 The autocrine functions of muscarinic receptors broadly fall into two areas - control of cell growth or proliferation and mediation of the release of chemical mediators from epithelial cells, ultimately causing muscle relaxation. The former particularly are involved in embryological development, oncogenesis, keratinocyte function and immune responsiveness. The latter regulate contractility of smooth muscle in the vasculature, airways and urinary bladder. 4 Most attention has focused on muscarinic M1 or M3 receptors which mediate lymphocyte immunoresponsiveness, cell migration and release of smooth muscle relaxant factors. Muscarinic M4 receptors are implicated in the regulation of keratinocyte adhesion and M2 receptors in stem cell proliferation and development. Little data are available concerning the M5 receptor, partly due to the difficulties in defining the subtype pharmacologically. 5 The autocrine functions of acetylcholine, like those in the nervous system, involve activation of several muscarinic receptor subtypes. Consequently, the role of these subtypes in autocrine, as well neuronal cholinergic systems, significantly expands their importance in physiology and pathophysiology.
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Affiliation(s)
- R M Eglen
- DiscoveRx Corp, 42501, Albrae St., Suite 100, Fremont, CA 94538, USA
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17
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Eglen RM. Muscarinic Receptor Subtype Pharmacology and Physiology. PROGRESS IN MEDICINAL CHEMISTRY 2005; 43:105-36. [PMID: 15850824 DOI: 10.1016/s0079-6468(05)43004-0] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Affiliation(s)
- Richard M Eglen
- DiscoveRx Corporation, Albrae Street, Fremont, CA 94538, USA
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18
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Chackalamannil S, Doller D, McQuade R, Ruperto V. Himbacine analogs as muscarinic receptor antagonists––effects of tether and heterocyclic variations. Bioorg Med Chem Lett 2004; 14:3967-70. [PMID: 15225708 DOI: 10.1016/j.bmcl.2004.05.047] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2004] [Accepted: 05/21/2004] [Indexed: 11/17/2022]
Abstract
A number of analogs of the natural product himbacine were synthesized employing variations at the heterocyclic unit and the tether that links the heterocyclic unit to the tricyclic motif. Several of these analogs had M(2) affinity and M(1)/M(2) selectivity comparable to those of himbacine. The structural and stereochemical requirements of the heterocyclic unit for muscarinic binding are discussed in the light of these data.
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Affiliation(s)
- Samuel Chackalamannil
- Schering-Plough Research Institute, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA.
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