1
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Roberts CF, Cao Y, Im W, Nichols RA, Lukas RJ, George AA. Neuroprotective amyloid β N-terminal peptides differentially alter human α7- and α7β2-nicotinic acetylcholine (nACh) receptor single-channel properties. Br J Pharmacol 2024; 181:3172-3191. [PMID: 38720171 DOI: 10.1111/bph.16381] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 03/06/2024] [Accepted: 03/08/2024] [Indexed: 08/03/2024] Open
Abstract
BACKGROUND AND PURPOSE Oligomeric amyloid β 1-42 (oAβ1-42) exhibits agonist-like action at human α7- and α7β2-containing nicotinic receptors. The N-terminal amyloid β1-15 fragment (N-Aβ fragment) modulates presynaptic calcium and enhances hippocampal-based synaptic plasticity via α7-containing nicotinic receptors. Further, the N-Aβ fragment and its core sequence, the N-amyloid-beta core hexapeptide (N-Aβcore), protect against oAβ1-42-associated synapto- and neurotoxicity. Here, we investigated how oAβ1-42, the N-Aβ fragment, and the N-Aβcore regulate the single-channel properties of α7- and α7β2-nicotinic receptors. EXPERIMENTAL APPROACH Single-channel recordings measured the impact of acetylcholine, oAβ1-42, the N-Aβ fragment, and the N-Aβcore on the unitary properties of human α7- and α7β2-containing nicotinic receptors expressed in nicotinic-null SH-EP1 cells. Molecular dynamics simulations identified potential sites of interaction between the N-Aβ fragment and orthosteric α7+/α7- and α7+/β2- nicotinic receptor binding interfaces. KEY RESULTS The N-Aβ fragment and N-Aβcore induced α7- and α7β2-nicotinic receptor single-channel openings. Relative to acetylcholine, oAβ1-42 preferentially enhanced α7β2-nicotinic receptor single-channel open probability and open-dwell times. Co-application with the N-Aβcore neutralized these effects. Further, administration of the N-Aβ fragment alone, or in combination with acetylcholine or oAβ1-42, selectively enhanced α7-nicotinic receptor open probability and open-dwell times (compared to acetylcholine or oAβ1-42). CONCLUSIONS AND IMPLICATIONS Amyloid-beta peptides demonstrate functional diversity in regulating α7- and α7β2-nicotinic receptor function, with implications for a wide range of nicotinic receptor-mediated functions in Alzheimer's disease. The effects of these peptides on α7- and/or α7β2-nicotinic receptors revealed complex interactions with these subtypes, providing novel insights into the neuroprotective actions of amyloid β-derived fragments against the toxic effects of oAβ1-42.
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Affiliation(s)
- Catherine F Roberts
- Department of Life Sciences, University of Bath, Bath, UK
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Yiwei Cao
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania, USA
| | - Wonpil Im
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania, USA
| | - Robert A Nichols
- Department of Cell & Molecular Biology, University of Hawaii at Manoa, Honolulu, Hawaii, USA
| | | | - Andrew A George
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia, USA
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2
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Sabec MH, Savage QR, Wood JL, Maskos U. Targeting high-affinity nicotinic receptors protects against the functional consequences of β-amyloid in mouse hippocampus. Mol Psychiatry 2024:10.1038/s41380-024-02666-7. [PMID: 39164528 DOI: 10.1038/s41380-024-02666-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 06/29/2024] [Accepted: 07/04/2024] [Indexed: 08/22/2024]
Abstract
The accumulation of β-amyloid oligomers is a hallmark of Alzheimer's disease, inducing neural and network dysfunction in the early stages of pathology. The hippocampus is affected early in the pathogenesis of AD, however the impact of soluble β-amyloid on the dentate gyrus (DG) subregion of the hippocampus and its interaction with nicotinic acetylcholine receptors (nAChRs) within this region are not known. Using a localized model of over-expression, we show that β-amyloid induces early-onset neuronal hyperactivity and hippocampal-dependent memory deficits in mice. Further, we find the DG region to be under potent and sub-type specific nicotinic control in both healthy and pathophysiological conditions, with targeted receptor inhibition leading to a mnemonic rescue against localized amyloidosis. We show that while neurogenesis and synaptic functions are not severely affected in our model, reducing β2-containing nAChR function is associated with the promotion of young adult-born neurons within the pathological network, suggesting a possible protective mechanism. Our data thus reveal the DG network level changes which occur in the early-stages of β-amyloid accumulation and highlight the downstream consequences of targeted nicotinic neuromodulation.
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Affiliation(s)
- Marie H Sabec
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Integrative Neurobiology of Cholinergic Systems, 75015, Paris, France.
- Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, BS8 1TD, UK.
| | - Quentin R Savage
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX, 76798, USA
| | - John L Wood
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX, 76798, USA
| | - Uwe Maskos
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Integrative Neurobiology of Cholinergic Systems, 75015, Paris, France.
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3
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Akyuz E, Arulsamy A, Aslan FS, Sarisözen B, Guney B, Hekimoglu A, Yilmaz BN, Retinasamy T, Shaikh MF. An Expanded Narrative Review of Neurotransmitters on Alzheimer's Disease: The Role of Therapeutic Interventions on Neurotransmission. Mol Neurobiol 2024:10.1007/s12035-024-04333-y. [PMID: 39012443 DOI: 10.1007/s12035-024-04333-y] [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: 07/06/2023] [Accepted: 06/24/2024] [Indexed: 07/17/2024]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease. The accumulation of amyloid-β (Aβ) plaques and tau neurofibrillary tangles are the key players responsible for the pathogenesis of the disease. The accumulation of Aβ plaques and tau affect the balance in chemical neurotransmitters in the brain. Thus, the current review examined the role of neurotransmitters in the pathogenesis of Alzheimer's disease and discusses the alterations in the neurochemical activity and cross talk with their receptors and transporters. In the presence of Aβ plaques and neurofibrillary tangles, changes may occur in the expression of neuronal receptors which in turn triggers excessive release of glutamate into the synaptic cleft contributing to cell death and neuronal damage. The GABAergic system may also be affected by AD pathology in a similar way. In addition, decreased receptors in the cholinergic system and dysfunction in the dopamine neurotransmission of AD pathology may also contribute to the damage to cognitive function. Moreover, the presence of deficiencies in noradrenergic neurons within the locus coeruleus in AD suggests that noradrenergic stimulation could be useful in addressing its pathophysiology. The regulation of melatonin, known for its effectiveness in enhancing cognitive function and preventing Aβ accumulation, along with the involvement of the serotonergic system and histaminergic system in cognition and memory, becomes remarkable for promoting neurotransmission in AD. Additionally, nitric oxide and adenosine-based therapeutic approaches play a protective role in AD by preventing neuroinflammation. Overall, neurotransmitter-based therapeutic strategies emerge as pivotal for addressing neurotransmitter homeostasis and neurotransmission in the context of AD. This review discussed the potential for neurotransmitter-based drugs to be effective in slowing and correcting the neurodegenerative processes in AD by targeting the neurochemical imbalance in the brain. Therefore, neurotransmitter-based drugs could serve as a future therapeutic strategy to tackle AD.
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Affiliation(s)
- Enes Akyuz
- Department of Biophysics, International School of Medicine, University of Health Sciences, Istanbul, Turkey
- Department of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Alina Arulsamy
- Neuropharmacology Research Laboratory, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500, Bandar Sunway, Selangor, Malaysia.
| | | | - Bugra Sarisözen
- School of Medicine, Tekirdağ Namık Kemal University, Tekirdağ, Turkey
| | - Beyzanur Guney
- International School of Medicine, University of Health Sciences, Istanbul, Turkey
| | | | - Beyza Nur Yilmaz
- International School of Medicine, University of Health Sciences, Istanbul, Turkey
| | - Thaarvena Retinasamy
- Neuropharmacology Research Laboratory, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500, Bandar Sunway, Selangor, Malaysia
| | - Mohd Farooq Shaikh
- Neuropharmacology Research Laboratory, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, 47500, Bandar Sunway, Selangor, Malaysia.
- School of Dentistry and Medical Sciences, Charles Sturt University, Orange, New South Wales, 2800, Australia.
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4
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Pastor V, Medina JH. α7 nicotinic acetylcholine receptor in memory processing. Eur J Neurosci 2024; 59:2138-2154. [PMID: 36634032 DOI: 10.1111/ejn.15913] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 01/03/2023] [Accepted: 01/06/2023] [Indexed: 01/13/2023]
Abstract
Information storage in the brain involves different memory types and stages that are processed by several brain regions. Cholinergic pathways through acetylcholine receptors actively participate on memory modulation, and their disfunction is associated with cognitive decline in several neurological disorders. During the last decade, the role of α7 subtype of nicotinic acetylcholine receptors in different memory stages has been studied. However, the information about their role in memory processing is still scarce. In this review, we attempt to identify brain areas where α7 nicotinic receptors have an essential role in different memory types and stages. In addition, we discuss recent work implicating-or not-α7 nicotinic receptors as promising pharmacological targets for memory impairment associated with neurological disorders.
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Affiliation(s)
- Verónica Pastor
- Instituto de Biología Celular y Neurociencia "Prof. Eduardo De Robertis" (IBCN), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
- Facultad de Medicina, Departamento de Ciencias Fisiológicas, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Jorge H Medina
- Instituto de Biología Celular y Neurociencia "Prof. Eduardo De Robertis" (IBCN), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
- Instituto Tecnológico de Buenos Aires (ITBA), Buenos Aires, Argentina
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5
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Pradhan A, Mounford H, Peixinho J, Rea E, Epeslidou E, Scott JS, Cull J, Maxwell S, Webster R, Beeson D, Dong YY, Prekovic S, Bermudez I, Newbury DF. Unraveling the molecular interactions between α7 nicotinic receptor and a RIC3 variant associated with backward speech. Cell Mol Life Sci 2024; 81:129. [PMID: 38472514 DOI: 10.1007/s00018-024-05149-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 01/28/2024] [Accepted: 01/30/2024] [Indexed: 03/14/2024]
Abstract
Recent work putatively linked a rare genetic variant of the chaperone Resistant to Inhibitors of acetylcholinesterase (RIC3) (NM_024557.4:c.262G > A, NP_078833.3:p.G88R) to a unique ability to speak backwards, a language skill that is associated with exceptional working memory capacity. RIC3 is important for the folding, maturation, and functional expression of α7 nicotinic acetylcholine receptors (nAChR). We compared and contrasted the effects of RIC3G88R on assembly, cell surface expression, and function of human α7 receptors using fluorescent protein tagged α7 nAChR and Förster resonance energy transfer (FRET) microscopy imaging in combination with functional assays and 125I-α-bungarotoxin binding. As expected, the wild-type RIC3 protein was found to increase both cell surface and functional expression of α7 receptors. In contrast, the variant form of RIC3 decreased both. FRET analysis showed that RICG88R increased the interactions between RIC3 and α7 protein in the endoplasmic reticulum. These results provide interesting and novel data to show that a RIC3 variant alters the interaction of RIC3 and α7, which translates to decreased cell surface and functional expression of α7 nAChR.
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Affiliation(s)
- Aditi Pradhan
- Department of Biological and Molecular Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, OX3 0BP, England
| | - Hayley Mounford
- Department of Biological and Molecular Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, OX3 0BP, England
| | - Jessica Peixinho
- Department of Biological and Molecular Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, OX3 0BP, England
| | - Edward Rea
- Department of Biological and Molecular Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, OX3 0BP, England
- Oxford Brookes Centre for Bioimaging, Oxford Brookes University, Oxford, OX3 0BP, England
| | - Emmanouela Epeslidou
- Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Julia S Scott
- Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Joanna Cull
- Department of Biological and Molecular Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, OX3 0BP, England
| | - Susan Maxwell
- Neurosciences Group, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, OX3 9DS, England
| | - Richard Webster
- Neurosciences Group, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, OX3 9DS, England
| | - David Beeson
- Neurosciences Group, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, OX3 9DS, England
| | - Yin Yao Dong
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 9DS, England
| | - Stefan Prekovic
- Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Isabel Bermudez
- Department of Biological and Molecular Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, OX3 0BP, England
| | - Dianne F Newbury
- Department of Biological and Molecular Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, OX3 0BP, England.
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6
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Crestini A, Carbone E, Rivabene R, Ancidoni A, Rosa P, Tata AM, Fabrizi E, Locuratolo N, Vanacore N, Lacorte E, Piscopo P. A Systematic Review on Drugs Acting as Nicotinic Acetylcholine Receptor Agonists in the Treatment of Dementia. Cells 2024; 13:237. [PMID: 38334629 PMCID: PMC10854606 DOI: 10.3390/cells13030237] [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: 12/11/2023] [Revised: 01/10/2024] [Accepted: 01/17/2024] [Indexed: 02/10/2024] Open
Abstract
Acetylcholine signaling is attenuated in early Alzheimer's disease (AD) and other dementias. A significant reduction in the expression of nicotinic acetylcholine receptors (nAChRs) in the brain of AD patients has also been reported in several molecular biological and in situ labeling studies. The modulation of the functional deficit of the cholinergic system as a pharmacological target could therefore have a clinical benefit, which is not to be neglected. This systematic review was conducted to identify clinical trials, which evaluated the safety and efficacy of nicotinic acetylcholine receptor agonists using Clinicaltrial (CT) and EudraCT databases. Structured searches identified 39 trials, which used 15 different drugs designed to increase the function of the nAChRs. Most of the identified clinical trials were phase II trials, with some of them classified as ongoing for several years. The systematic screening of the literature led to the selection of 14 studies out of the 8261 bibliographic records retrieved. Six trials reported detailed data on adverse events associated with the intervention, while twelve trials reported data on efficacy measures, such as attention, behavior and cognition. Overall, smost of the physical side effects of cholinergic agonists were reported to be well tolerated. Some trials also reported improvements in attention. However, the efficacy of these drugs in other cognitive and behavioral outcomes remains highly controversial.
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Affiliation(s)
- Alessio Crestini
- Department of Neuroscience, Italian National Institute of Health, 00161 Rome, Italy; (E.C.); (R.R.); (P.P.)
| | - Elena Carbone
- Department of Neuroscience, Italian National Institute of Health, 00161 Rome, Italy; (E.C.); (R.R.); (P.P.)
| | - Roberto Rivabene
- Department of Neuroscience, Italian National Institute of Health, 00161 Rome, Italy; (E.C.); (R.R.); (P.P.)
| | - Antonio Ancidoni
- National Center for Disease Prevention and Health Promotion, Italian National Institute of Health, 00161 Rome, Italy; (A.A.); (N.L.); (N.V.); (E.L.)
| | - Paolo Rosa
- Department of Medical-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Polo Pontino, 04100 Latina, Italy;
- ICOT (Institute of Traumatology and Orthopaedic Surgery), 04100 Latina, Italy
| | - Ada Maria Tata
- Department of Biology and Biotechnologies Charles Darwin, Sapienza University of Rome, 00185 Rome, Italy;
- Research Center in Neurobiology Daniel Bovet, Sapienza University of Rome, 00185 Rome, Italy
| | - Elisa Fabrizi
- National Center for Disease Prevention and Health Promotion, Italian National Institute of Health, 00161 Rome, Italy; (A.A.); (N.L.); (N.V.); (E.L.)
- Doctoral School, The Catholic University of Valencia San Vicente Mártir, 46001 Valencia, Spain
| | - Nicoletta Locuratolo
- National Center for Disease Prevention and Health Promotion, Italian National Institute of Health, 00161 Rome, Italy; (A.A.); (N.L.); (N.V.); (E.L.)
| | - Nicola Vanacore
- National Center for Disease Prevention and Health Promotion, Italian National Institute of Health, 00161 Rome, Italy; (A.A.); (N.L.); (N.V.); (E.L.)
| | - Eleonora Lacorte
- National Center for Disease Prevention and Health Promotion, Italian National Institute of Health, 00161 Rome, Italy; (A.A.); (N.L.); (N.V.); (E.L.)
| | - Paola Piscopo
- Department of Neuroscience, Italian National Institute of Health, 00161 Rome, Italy; (E.C.); (R.R.); (P.P.)
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7
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Nagahama T, Nakajima H, Wakuta M, Kasahara Y, Narita K, Nagahama S. Administration of amyloid-β oligomer to the buccal ganglia may reduce food intake and cholinergic synaptic responses within the feeding neural circuit in Aplysia kurodai. Neurosci Res 2023; 196:32-39. [PMID: 37328111 DOI: 10.1016/j.neures.2023.06.004] [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: 03/23/2023] [Revised: 05/23/2023] [Accepted: 06/11/2023] [Indexed: 06/18/2023]
Abstract
Anorexia is a behavioral change caused by functional brain disorders in patients with Alzheimer's disease (AD). Amyloid-β (1-42) oligomers (o-Aβ) are possible causative agents of AD that impair signaling via synaptic dysfunction. In this study, we used Aplysia kurodai to study functional disorders of the brain through o-Aβ. Administration of o-Aβ to the buccal ganglia (feeding brain for oral movements) by surgical treatment significantly reduced food intake for at least five days. Furthermore, we explored the effects of o-Aβ on the synaptic function in the feeding neural circuit, focusing on a specific inhibitory synaptic response in jaw-closing motor neurons produced by cholinergic buccal multi-action neurons because we recently found that this cholinergic response decreases with aging, which is consistent with the cholinergic hypothesis for aging. Administration of o-Aβ to the buccal ganglia significantly reduced the synaptic response within minutes, whereas administration of amyloid-β (1-42) monomers did not. These results suggest that o-Aβ may impair the cholinergic synapses, even in Aplysia, which is consistent with the cholinergic hypothesis for AD.
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Affiliation(s)
- Tatsumi Nagahama
- Department of Biophysics, Faculty of Pharmaceutical Science, Toho University, Funabashi 274-8510, Japan; Faculty of Health and Medical Science, Teikyo Heisei University, Tokyo 170-8445, Japan.
| | - Hiroshi Nakajima
- Department of Biophysics, Faculty of Pharmaceutical Science, Toho University, Funabashi 274-8510, Japan
| | - Mizuki Wakuta
- Department of Biophysics, Faculty of Pharmaceutical Science, Toho University, Funabashi 274-8510, Japan
| | - Yuse Kasahara
- Department of Biophysics, Faculty of Pharmaceutical Science, Toho University, Funabashi 274-8510, Japan
| | - Kouki Narita
- Department of Biophysics, Faculty of Pharmaceutical Science, Toho University, Funabashi 274-8510, Japan
| | - Setsuko Nagahama
- Faculty of Health and Medical Science, Teikyo Heisei University, Tokyo 170-8445, Japan
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8
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Papke RL. The many enigmas of nicotine. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2023; 99:327-354. [PMID: 38467485 DOI: 10.1016/bs.apha.2023.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
This review discusses the diverse effects of nicotine on the various nicotinic acetylcholine receptors of the central and peripheral nervous system and how those effects may promote the usage and addiction to tobacco products.
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Affiliation(s)
- Roger L Papke
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL, United States.
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9
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Viscarra F, Chrestia JF, Sanchez Y, Pérez EG, Biggin PC, Bouzat C, Bermudez I, López JJ. Side Groups Convert the α7 Nicotinic Receptor Agonist Ether Quinuclidine into a Type I Positive Allosteric Modulator. ACS Chem Neurosci 2023; 14:2876-2887. [PMID: 37535446 DOI: 10.1021/acschemneuro.3c00225] [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] [Indexed: 08/05/2023] Open
Abstract
The quinuclidine scaffold has been extensively used for the development of nicotinic acetylcholine receptor (nAChR) agonists, with hydrophobic substituents at position 3 of the quinuclidine framework providing selectivity for α7 nAChRs. In this study, six new ligands (4-9) containing a 3-(pyridin-3-yloxy)quinuclidine moiety (ether quinuclidine) were synthesized to gain a better understanding of the structural-functional properties of ether quinuclidines. To evaluate the pharmacological activity of these ligands, two-electrode voltage-clamp and single-channel recordings were performed. Only ligand 4 activated α7 nAChR. Ligands 5 and 7 had no effects on α7 nAChR, but ligands 6, 8, and 9 potentiated the currents evoked by ACh. Ligand 6 was the most potent and efficacious of the potentiating ligands, with an estimated EC50 for potentiation of 12.6 ± 3.32 μM and a maximal potentiation of EC20 ACh responses of 850 ± 120%. Ligand 6 increased the maximal ACh responses without changing the kinetics of the current responses. At the single-channel level, the potentiation exerted by ligand 6 was evidenced in the low micromolar concentration range by the appearance of prolonged bursts of channel openings. Furthermore, computational studies revealed the preference of ligand 6 for an intersubunit site in the transmembrane domain and highlighted some putative key interactions that explain the different profiles of the synthesized ligands. Notably, Met276 in the 15' position of the transmembrane domain 2 almost abolished the effects of ligand 6 when mutated to Leu. We conclude that ligand 6 is a novel type I positive allosteric modulator (PAM-I) of α7 nAChR.
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Affiliation(s)
- Franco Viscarra
- Department of Biological and Medical Sciences, Oxford Brookes University, Gipsy Lane, Oxford OX3 0BP, U.K
- Structural Bioinformatics and Computational Biochemistry, Department of Biochemistry, Oxford University, South Parks Road, Oxford OX1 3QU, U.K
| | - Juan Facundo Chrestia
- Departamento de Biología, Bioquímica y Farmacia, Instituto de Investigaciones Bioquímicas de Bahía Blanca, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Camino La Carrindanga Km 7, Bahía Blanca 8000, Argentina
| | - Yaima Sanchez
- Department of Organic Chemistry, Faculty of Chemistry, Universidad de Concepción, Edmundo Larenas 129, Concepción 4070371, Chile
| | - Edwin G Pérez
- Department of Organic Chemistry, Faculty of Chemistry and Pharmacy, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago 7820436, Chile
| | - Philip C Biggin
- Structural Bioinformatics and Computational Biochemistry, Department of Biochemistry, Oxford University, South Parks Road, Oxford OX1 3QU, U.K
| | - Cecilia Bouzat
- Departamento de Biología, Bioquímica y Farmacia, Instituto de Investigaciones Bioquímicas de Bahía Blanca, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Camino La Carrindanga Km 7, Bahía Blanca 8000, Argentina
| | - Isabel Bermudez
- Department of Biological and Medical Sciences, Oxford Brookes University, Gipsy Lane, Oxford OX3 0BP, U.K
| | - Jhon J López
- Department of Organic Chemistry, Faculty of Chemistry, Universidad de Concepción, Edmundo Larenas 129, Concepción 4070371, Chile
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10
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Olivero G, Grilli M, Marchi M, Pittaluga A. Metamodulation of presynaptic NMDA receptors: New perspectives for pharmacological interventions. Neuropharmacology 2023; 234:109570. [PMID: 37146939 DOI: 10.1016/j.neuropharm.2023.109570] [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: 02/15/2023] [Revised: 04/26/2023] [Accepted: 05/02/2023] [Indexed: 05/07/2023]
Abstract
Metamodulation shifted the scenario of the central neuromodulation from a simplified unimodal model to a multimodal one. It involves different receptors/membrane proteins physically associated or merely colocalized that act in concert to control the neuronal functions influencing each other. Defects or maladaptation of metamodulation would subserve neuropsychiatric disorders or even synaptic adaptations relevant to drug dependence. Therefore, this "vulnerability" represents a main issue to be deeply analyzed to predict its aetiopathogenesis, but also to propose targeted pharmaceutical interventions. The review focusses on presynaptic release-regulating NMDA receptors and on some of the mechanisms of their metamodulation described in the literature. Attention is paid to the interactors, including both ionotropic and metabotropic receptors, transporters and intracellular proteins, which metamodulate their responsiveness in physiological conditions but also undergo adaptation that are relevant to neurological dysfunctions. All these structures are attracting more and more the interest as promising druggable targets for the treatment of NMDAR-related central diseases: these substances would not exert on-off control of the colocalized NMDA receptors (as usually observed with NMDAR full agonists/antagonists), but rather modulate their functions, with the promise of limiting side effects that would favor their translation from preclinic to clinic.
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Affiliation(s)
- Guendalina Olivero
- Department of Pharmacy, University of Genoa, Viale Cembrano 4, 16148, Genoa, Italy
| | - Massimo Grilli
- Department of Pharmacy, University of Genoa, Viale Cembrano 4, 16148, Genoa, Italy; Inter-University Center for the Promotion of the 3Rs Principles in Teaching & Research (Centro 3R), 16148, Genoa, Italy.
| | - Mario Marchi
- Department of Pharmacy, University of Genoa, Viale Cembrano 4, 16148, Genoa, Italy
| | - Anna Pittaluga
- Department of Pharmacy, University of Genoa, Viale Cembrano 4, 16148, Genoa, Italy; Inter-University Center for the Promotion of the 3Rs Principles in Teaching & Research (Centro 3R), 16148, Genoa, Italy
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11
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Whiteaker P, George AA. Discoveries and future significance of research into amyloid-beta/α7-containing nicotinic acetylcholine receptor (nAChR) interactions. Pharmacol Res 2023; 191:106743. [PMID: 37084859 DOI: 10.1016/j.phrs.2023.106743] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 03/13/2023] [Accepted: 03/21/2023] [Indexed: 04/23/2023]
Abstract
Initiated by findings that Alzheimer's disease is associated with a profound loss of cholinergic markers in human brain, decades of studies have examined the interactions between specific subtypes of nicotinic acetylcholine receptors and amyloid-β [derive from the amyloid precursor protein (APP), which is cleaved to yield variable isoforms of amyloid-β]. We review the evolving understanding of amyloid-β's roles in Alzheimer's disease and pioneering studies that highlighted a role of nicotinic acetylcholine receptors in mediating important aspects of amyloid-β's effects. This review also surveys the current state of research into amyloid-β / nicotinic acetylcholine receptor interactions. The field has reached an exciting point in which common themes are emerging from the wide range of prior research and a range of accessible, relevant model systems are available to drive further progress. We highlight exciting new areas of inquiry and persistent challenges that need to be considered while conducting this research. Studies of amyloid-β and nicotinic acetylcholine receptor populations that it interacts with provide opportunities for innovative basic and translational scientific breakthroughs related to nicotinic receptors biology, Alzheimer's disease, and cholinergic contributions to cognition more broadly.
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Affiliation(s)
- Paul Whiteaker
- Virginia Commonwealth University School of Medicine, Department of Pharmacology and Toxicology, VCU Health Sciences Research Building, Box 980613, Richmond, VA 23298-0613, USA
| | - Andrew A George
- Virginia Commonwealth University School of Medicine, Department of Pharmacology and Toxicology, VCU Health Sciences Research Building, Box 980613, Richmond, VA 23298-0613, USA.
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12
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Terry AV, Jones K, Bertrand D. Nicotinic acetylcholine receptors in neurological and psychiatric diseases. Pharmacol Res 2023; 191:106764. [PMID: 37044234 DOI: 10.1016/j.phrs.2023.106764] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/30/2023] [Accepted: 04/07/2023] [Indexed: 04/14/2023]
Abstract
Neuronal nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels that are widely distributed both pre- and post-synaptically in the mammalian brain. By modulating cation flux across cell membranes, neuronal nAChRs regulate neuronal excitability and the release of a variety of neurotransmitters to influence multiple physiologic and behavioral processes including synaptic plasticity, motor function, attention, learning and memory. Abnormalities of neuronal nAChRs have been implicated in the pathophysiology of neurologic disorders including Alzheimer's disease, Parkinson's disease, epilepsy, and Tourette´s syndrome, as well as psychiatric disorders including schizophrenia, depression, and anxiety. The potential role of nAChRs in a particular illness may be indicated by alterations in the expression of nAChRs in relevant brain regions, genetic variability in the genes encoding for nAChR subunit proteins, and/or clinical or preclinical observations where specific ligands showed a therapeutic effect. Over the past 25 years, extensive preclinical and some early clinical evidence suggested that ligands at nAChRs might have therapeutic potential for neurologic and psychiatric disorders. However, to date the only approved indications for nAChR ligands are smoking cessation and the treatment of dry eye disease. It has been argued that progress in nAChR drug discovery has been limited by translational gaps between the preclinical models and the human disease as well as unresolved questions regarding the pharmacological goal (i.e., agonism, antagonism or receptor desensitization) depending on the disease.
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Affiliation(s)
- Alvin V Terry
- Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, Georgia, 30912.
| | - Keri Jones
- Educational Innovation Institute, Medical College of Georgia at Augusta University, Augusta, Georgia, 30912
| | - Daniel Bertrand
- HiQScreen Sàrl, 6, rte de Compois, 1222 Vésenaz, Geneva, Switzerland
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13
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Hone AJ, McIntosh JM. Nicotinic acetylcholine receptors: Therapeutic targets for novel ligands to treat pain and inflammation. Pharmacol Res 2023; 190:106715. [PMID: 36868367 PMCID: PMC10691827 DOI: 10.1016/j.phrs.2023.106715] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/22/2023] [Accepted: 02/28/2023] [Indexed: 03/05/2023]
Abstract
Nicotinic acetylcholine receptors (nAChRs) have been historically defined as ligand-gated ion channels and function as such in the central and peripheral nervous systems. Recently, however, non-ionic signaling mechanisms via nAChRs have been demonstrated in immune cells. Furthermore, the signaling pathways where nAChRs are expressed can be activated by endogenous ligands other than the canonical agonists acetylcholine and choline. In this review, we discuss the involvement of a subset of nAChRs containing α7, α9, and/or α10 subunits in the modulation of pain and inflammation via the cholinergic anti-inflammatory pathway. Additionally, we review the most recent advances in the development of novel ligands and their potential as therapeutics.
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Affiliation(s)
- Arik J Hone
- School of Biological Sciences University of Utah, Salt Lake City, UT, USA; MIRECC, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, UT, USA.
| | - J Michael McIntosh
- School of Biological Sciences University of Utah, Salt Lake City, UT, USA; Department of Psychiatry, University of Utah, Salt Lake City, UT, USA; George E. Whalen Veterans Affairs Medical Center, Salt Lake City, UT, USA.
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14
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Tae HS, Adams DJ. Nicotinic acetylcholine receptor subtype expression, function, and pharmacology: Therapeutic potential of α-conotoxins. Pharmacol Res 2023; 191:106747. [PMID: 37001708 DOI: 10.1016/j.phrs.2023.106747] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 03/22/2023] [Accepted: 03/27/2023] [Indexed: 04/03/2023]
Abstract
The pentameric nicotinic acetylcholine receptors (nAChRs) are typically classed as muscle- or neuronal-type, however, the latter has also been reported in non-neuronal cells. Given their broad distribution, nAChRs mediate numerous physiological and pathological processes including synaptic transmission, presynaptic modulation of transmitter release, neuropathic pain, inflammation, and cancer. There are 17 different nAChR subunits and combinations of these subunits produce subtypes with diverse pharmacological properties. The expression and role of some nAChR subtypes have been extensively deciphered with the aid of knock-out models. Many nAChR subtypes expressed in heterologous systems are selectively targeted by the disulfide-rich α-conotoxins. α-Conotoxins are small peptides isolated from the venom of cone snails, and a number of them have potential pharmaceutical value.
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15
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Becchetti A, Grandi LC, Cerina M, Amadeo A. Nicotinic acetylcholine receptors and epilepsy. Pharmacol Res 2023; 189:106698. [PMID: 36796465 DOI: 10.1016/j.phrs.2023.106698] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 02/04/2023] [Accepted: 02/13/2023] [Indexed: 02/16/2023]
Abstract
Despite recent advances in understanding the causes of epilepsy, especially the genetic, comprehending the biological mechanisms that lead to the epileptic phenotype remains difficult. A paradigmatic case is constituted by the epilepsies caused by altered neuronal nicotinic acetylcholine receptors (nAChRs), which exert complex physiological functions in mature as well as developing brain. The ascending cholinergic projections exert potent control of forebrain excitability, and wide evidence implicates nAChR dysregulation as both cause and effect of epileptiform activity. First, tonic-clonic seizures are triggered by administration of high doses of nicotinic agonists, whereas non-convulsive doses have kindling effects. Second, sleep-related epilepsy can be caused by mutations on genes encoding nAChR subunits widely expressed in the forebrain (CHRNA4, CHRNB2, CHRNA2). Third, in animal models of acquired epilepsy, complex time-dependent alterations in cholinergic innervation are observed following repeated seizures. Heteromeric nAChRs are central players in epileptogenesis. Evidence is wide for autosomal dominant sleep-related hypermotor epilepsy (ADSHE). Studies of ADSHE-linked nAChR subunits in expression systems suggest that the epileptogenic process is promoted by overactive receptors. Investigation in animal models of ADSHE indicates that expression of mutant nAChRs can lead to lifelong hyperexcitability by altering i) the function of GABAergic populations in the mature neocortex and thalamus, ii) synaptic architecture during synaptogenesis. Understanding the balance of the epileptogenic effects in adult and developing networks is essential to plan rational therapy at different ages. Combining this knowledge with a deeper understanding of the functional and pharmacological properties of individual mutations will advance precision and personalized medicine in nAChR-dependent epilepsy.
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Affiliation(s)
- Andrea Becchetti
- Department of Biotechnology and Biosciences, and NeuroMI (Milan Center of Neuroscience), University of Milano-Bicocca, Piazza della Scienza 2, Milano 20126, Italy.
| | - Laura Clara Grandi
- Department of Biotechnology and Biosciences, and NeuroMI (Milan Center of Neuroscience), University of Milano-Bicocca, Piazza della Scienza 2, Milano 20126, Italy.
| | - Marta Cerina
- Department of Biotechnology and Biosciences, and NeuroMI (Milan Center of Neuroscience), University of Milano-Bicocca, Piazza della Scienza 2, Milano 20126, Italy.
| | - Alida Amadeo
- Department of Biosciences, University of Milano, Via Celoria 26, Milano 20133, Italy.
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16
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Zhang H, Li X, Wang X, Xu J, Elefant F, Wang J. Cellular response to β-amyloid neurotoxicity in Alzheimer's disease and implications in new therapeutics. Animal Model Exp Med 2023; 6:3-9. [PMID: 36872303 PMCID: PMC9986234 DOI: 10.1002/ame2.12313] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 02/07/2023] [Indexed: 03/07/2023] Open
Abstract
β-Amyloid (Aβ) is a specific pathological hallmark of Alzheimer's disease (AD). Because of its neurotoxicity, AD patients exhibit multiple brain dysfunctions. Disease-modifying therapy (DMT) is the central concept in the development of AD therapeutics today, and most DMT drugs that are currently in clinical trials are anti-Aβ drugs, such as aducanumab and lecanemab. Therefore, understanding Aβ's neurotoxic mechanism is crucial for Aβ-targeted drug development. Despite its total length of only a few dozen amino acids, Aβ is incredibly diverse. In addition to the well-known Aβ1-42 , N-terminally truncated, glutaminyl cyclase (QC) catalyzed, and pyroglutamate-modified Aβ (pEAβ) is also highly amyloidogenic and far more cytotoxic. The extracellular monomeric Aβx-42 (x = 1-11) initiates the aggregation to form fibrils and plaques and causes many abnormal cellular responses through cell membrane receptors and receptor-coupled signal pathways. These signal cascades further influence many cellular metabolism-related processes, such as gene expression, cell cycle, and cell fate, and ultimately cause severe neural cell damage. However, endogenous cellular anti-Aβ defense processes always accompany the Aβ-induced microenvironment alterations. Aβ-cleaving endopeptidases, Aβ-degrading ubiquitin-proteasome system (UPS), and Aβ-engulfing glial cell immune responses are all essential self-defense mechanisms that we can leverage to develop new drugs. This review discusses some of the most recent advances in understanding Aβ-centric AD mechanisms and suggests prospects for promising anti-Aβ strategies.
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Affiliation(s)
- Haolin Zhang
- Faculty of Environment and LifeBeijing University of TechnologyBeijingChina
| | - Xianghua Li
- Faculty of Environment and LifeBeijing University of TechnologyBeijingChina
| | - Xiaoli Wang
- Faculty of Environment and LifeBeijing University of TechnologyBeijingChina
| | - Jiayu Xu
- Faculty of Environment and LifeBeijing University of TechnologyBeijingChina
| | - Felice Elefant
- Department of BiologyDrexel UniversityPhiladelphiaPennsylvaniaUSA
| | - Juan Wang
- Faculty of Environment and LifeBeijing University of TechnologyBeijingChina
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17
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Asogwa NC, Toji N, He Z, Shao C, Shibata Y, Tatsumoto S, Ishikawa H, Go Y, Wada K. Nicotinic acetylcholine receptors in a songbird brain. J Comp Neurol 2022; 530:1966-1991. [PMID: 35344610 DOI: 10.1002/cne.25314] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 02/21/2022] [Accepted: 02/23/2022] [Indexed: 11/07/2022]
Abstract
Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels that mediate fast synaptic transmission and cell signaling, which contribute to learning, memory, and the execution of motor skills. Birdsong is a complex learned motor skill in songbirds. Although the existence of 15 nAChR subunits has been predicted in the avian genome, their expression patterns and potential contributions to song learning and production have not been comprehensively investigated. Here, we cloned all the 15 nAChR subunits (ChrnA1-10, B2-4, D, and G) from the zebra finch brain and investigated the mRNA expression patterns in the neural pathways responsible for the learning and production of birdsong during a critical period of song learning. Although there were no detectable hybridization signals for ChrnA1, A6, A9, and A10, the other 11 nAChR subunits were uniquely expressed in one or more major subdivisions in the song nuclei of the songbird brain. Of these 11 subunits, ChrnA3-5, A7, and B2 were differentially regulated in the song nuclei compared with the surrounding anatomically related regions. ChrnA5 was upregulated during the critical period of song learning in the lateral magnocellular nucleus of the anterior nidopallium. Furthermore, single-cell RNA sequencing revealed ChrnA7 and B2 to be the major subunits expressed in neurons of the vocal motor nuclei HVC and robust nucleus of the arcopallium, indicating the potential existence of ChrnA7-homomeric and ChrnB2-heteromeric nAChRs in limited cell populations. These results suggest that relatively limited types of nAChR subunits provide functional contributions to song learning and production in songbirds.
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Affiliation(s)
| | - Noriyuki Toji
- Faculty of Science, Hokkaido University, Sapporo, Japan
| | - Ziwei He
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Chengru Shao
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Yukino Shibata
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Shoji Tatsumoto
- Cognitive Genomics Research Group, Exploratory Research Center on Life and Living Systems, National Institutes of Natural Sciences, Okazaki, Japan
| | - Hiroe Ishikawa
- Cognitive Genomics Research Group, Exploratory Research Center on Life and Living Systems, National Institutes of Natural Sciences, Okazaki, Japan
| | - Yasuhiro Go
- Cognitive Genomics Research Group, Exploratory Research Center on Life and Living Systems, National Institutes of Natural Sciences, Okazaki, Japan
- School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Japan
- Department of Physiological Sciences, National Institute for Physiological Sciences, Okazaki, Japan
| | - Kazuhiro Wada
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan
- Faculty of Science, Hokkaido University, Sapporo, Japan
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18
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Wu M, Liu CZ, Barrall EA, Rissman RA, Joiner WJ. Unbalanced Regulation of α7 nAChRs by Ly6h and NACHO Contributes to Neurotoxicity in Alzheimer's Disease. J Neurosci 2021; 41:8461-8474. [PMID: 34446574 PMCID: PMC8513707 DOI: 10.1523/jneurosci.0494-21.2021] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 08/17/2021] [Accepted: 08/19/2021] [Indexed: 12/24/2022] Open
Abstract
α7 nicotinic acetylcholine receptors (nAChRs) are widely expressed in the brain where they promote fast cholinergic synaptic transmission and serve important neuromodulatory functions. However, their high permeability to Ca2+ also predisposes them to contribute to disease states. Here, using transfected HEK-tsa cells and primary cultured hippocampal neurons from male and female rats, we demonstrate that two proteins called Ly6h and NACHO compete for access to α7 subunits, operating together but in opposition to maintain α7 assembly and activity within a narrow range that is optimal for neuronal function and viability. Using mixed gender human temporal cortex and cultured hippocampal neurons from rats we further show that this balance is perturbed during Alzheimer's disease (AD) because of amyloid β (Aβ)-driven reduction in Ly6h, with severe reduction leading to increased phosphorylated tau and α7-mediated neurotoxicity. Ly6h release into human CSF is also correlated with AD severity. Thus, Ly6h links cholinergic signaling, Aβ and phosphorylated tau and may serve as a novel marker for AD progression.SIGNIFICANCE STATEMENT One of the earliest and most persistent hypotheses regarding Alzheimer's disease (AD) attributes cognitive impairment to loss of cholinergic signaling. More recently, interest has focused on crucial roles for amyloid β (Aβ) and phosphorylated tau in Alzheimer's pathogenesis. Here, we demonstrate that these elements are linked by Ly6h and its counterpart, NACHO, functioning in opposition to maintain assembly of nicotinic acetylcholine receptors (nAChRs) within the physiological range. Our data suggests that Aβ shifts the balance away from Ly6h and toward NACHO, resulting in increased assembly of Ca2+-permeable nAChRs and thus a conversion of basal cholinergic to neurotoxic signaling.
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Affiliation(s)
- Meilin Wu
- Department of Pharmacology, University of California San Diego, La Jolla, California 92093
| | - Clifford Z Liu
- Department of Pharmacology, University of California San Diego, La Jolla, California 92093
| | - Erika A Barrall
- Department of Pharmacology, University of California San Diego, La Jolla, California 92093
| | - Robert A Rissman
- Department of Neurosciences, University of California San Diego, La Jolla, California 92093
- Alzheimer's Disease Research Center, University of California San Diego, La Jolla, California 92093
| | - William J Joiner
- Department of Pharmacology, University of California San Diego, La Jolla, California 92093
- Center for Circadian Biology, University of California San Diego, La Jolla, California 92093
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19
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Borroni V, Barrantes FJ. Homomeric and Heteromeric α7 Nicotinic Acetylcholine Receptors in Health and Some Central Nervous System Diseases. MEMBRANES 2021; 11:membranes11090664. [PMID: 34564481 PMCID: PMC8465519 DOI: 10.3390/membranes11090664] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/24/2021] [Accepted: 08/24/2021] [Indexed: 11/22/2022]
Abstract
Nicotinic acetylcholine receptors (nAChRs) are pentameric ligand-gated ion channels involved in the modulation of essential brain functions such as memory, learning, and attention. Homomeric α7 nAChR, formed exclusively by five identical α7 subunits, is involved in rapid synaptic transmission, whereas the heteromeric oligomers composed of α7 in combination with β subunits display metabotropic properties and operate in slower time frames. At the cellular level, the activation of nAChRs allows the entry of Na+ and Ca2+; the two cations depolarize the membrane and trigger diverse cellular signals, depending on the type of nAChR pentamer and neurons involved, the location of the intervening cells, and the networks of which these neuronal cells form part. These features make the α7 nAChR a central player in neurotransmission, metabolically associated Ca2+-mediated signaling, and modulation of diverse fundamental processes operated by other neurotransmitters in the brain. Due to its ubiquitous distribution and the multiple functions it displays in the brain, the α7 nAChR is associated with a variety of neurological and neuropsychiatric disorders whose exact etiopathogenic mechanisms are still elusive.
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Affiliation(s)
- Virginia Borroni
- Instituto de Tecnología en Polímeros y Nanotecnología (ITPN-UBA-CONICET), Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires C1127AAR, Argentina;
| | - Francisco J. Barrantes
- Laboratory of Molecular Neurobiology, Institute for Biomedical Research, UCA–CONICET, Faculty of Medical Sciences, Catholic University of Argentina, Av. Alicia Moreau de Justo 1600, Buenos Aires C1107AAZ, Argentina
- Correspondence:
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Mitić M, Lazarević-Pašti T. Does the application of acetylcholinesterase inhibitors in the treatment of Alzheimer's disease lead to depression? Expert Opin Drug Metab Toxicol 2021; 17:841-856. [PMID: 33999717 DOI: 10.1080/17425255.2021.1931681] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Introduction: Alzheimer's disease and depression are health conditions affecting millions of people around the world. Both are strongly related to the level of the neurotransmitter acetylcholine. Since cholinergic deficit is characteristic of Alzheimer's disease, acetylcholinesterase inhibitors are applied as relevant drugs for the treatment of this disease, elevating the level of acetylcholine. On the other hand, a high level of acetylcholine is found to be associated with the symptoms of clinical depression.Areas covered: This article aims to discuss if acetylcholinesterase inhibitors used as anti-Alzheimer's drugs could be the cause of the symptoms of clinical depression often linked to this neurological disorder. Emphasis will be put on drugs currently in use and on newly investigated natural products, which can inhibit AChE activity.Expert opinion: Currently, it is not proven that the patient treated for Alzheimer's disease is prone to increased risk for depression due to the acetylcholinesterase inhibition, but there are strong indications. The level of acetylcholine is not the only factor in highly complicated diseases like AD and depression. Still, it needs to be considered isolated, keeping in mind the nature of presently available therapy, especially during a rational drug design process.
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Affiliation(s)
- Miloš Mitić
- Department of Molecular Biology and Endocrinology, VINČA Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Tamara Lazarević-Pašti
- Department of Physical Chemistry, VINČA Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
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21
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GIPSON CD, BIMONTE-NELSON HA. Interactions between reproductive transitions during aging and addiction: promoting translational crosstalk between different fields of research. Behav Pharmacol 2021; 32:112-122. [PMID: 32960852 PMCID: PMC7965232 DOI: 10.1097/fbp.0000000000000591] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Discovery of neural mechanisms underlying neuropsychiatric disorders within the aging and addiction fields has been a main focus of the National Institutes of Health. However, there is a dearth of knowledge regarding the biological interactions of aging and addiction, which may have important influences on progression of disease and treatment outcomes in aging individuals with a history of chronic drug use. Thus, there is a large gap in these fields of research, which has slowed progress in understanding and treating substance use disorders (SUDs) as well as age-related diseases, specifically in women who experience precipitous reproductive cycle transitions during aging. The goal of this review is to highlight overlap of SUDs and age-related processes with a specific focus on menopause and smoking, and identify critical gaps. We have narrowed the focus of the review to smoking, as the majority of findings on hormonal and aging influences on drug use have come from this area of research. Further, we highlight female-specific issues such as transitional menopause and exogenous estrogen use. These issues may impact drug use cessation as well as outcomes with aging and age-related neurodegenerative diseases in women. We first review clinical studies for smoking, normal aging, and pathological aging, and discuss the few aging-related studies taking smoking history into account. Conversely, we highlight the dearth of clinical smoking studies taking age as a biological variable into account. Preclinical and clinical literature show that aging, age-related pathological brain disease, and addiction engage overlapping neural mechanisms. We hypothesize that these putative drivers interact in meaningful ways that may exacerbate disease and hinder successful treatment outcomes in such comorbid populations. We highlight areas where preclinical studies are needed to uncover neural mechanisms in aging and addiction processes. Collectively, this review highlights the need for crosstalk between different fields of research to address medical complexities of older adults, and specifically women, who smoke.
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Affiliation(s)
- Cassandra D. GIPSON
- Department of Family and Community Medicine, University of Kentucky, Lexington, KY
- Arizona Alzheimer’s Consortium
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22
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Bekdash RA. The Cholinergic System, the Adrenergic System and the Neuropathology of Alzheimer's Disease. Int J Mol Sci 2021; 22:ijms22031273. [PMID: 33525357 PMCID: PMC7865740 DOI: 10.3390/ijms22031273] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/23/2021] [Accepted: 01/25/2021] [Indexed: 12/16/2022] Open
Abstract
Neurodegenerative diseases are a major public health problem worldwide with a wide spectrum of symptoms and physiological effects. It has been long reported that the dysregulation of the cholinergic system and the adrenergic system are linked to the etiology of Alzheimer’s disease. Cholinergic neurons are widely distributed in brain regions that play a role in cognitive functions and normal cholinergic signaling related to learning and memory is dependent on acetylcholine. The Locus Coeruleus norepinephrine (LC-NE) is the main noradrenergic nucleus that projects and supplies norepinephrine to different brain regions. Norepinephrine has been shown to be neuroprotective against neurodegeneration and plays a role in behavior and cognition. Cholinergic and adrenergic signaling are dysregulated in Alzheimer’s disease. The degeneration of cholinergic neurons in nucleus basalis of Meynert in the basal forebrain and the degeneration of LC-NE neurons were reported in Alzheimer’s disease. The aim of this review is to describe current literature on the role of the cholinergic system and the adrenergic system (LC-NE) in the pathology of Alzheimer’s disease and potential therapeutic implications.
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Affiliation(s)
- Rola A Bekdash
- Department of Biological Sciences, Rutgers University, Newark, NJ 07102, USA
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23
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Toniolo S, Sen A, Husain M. Modulation of Brain Hyperexcitability: Potential New Therapeutic Approaches in Alzheimer's Disease. Int J Mol Sci 2020; 21:E9318. [PMID: 33297460 PMCID: PMC7730926 DOI: 10.3390/ijms21239318] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/30/2020] [Accepted: 12/05/2020] [Indexed: 12/12/2022] Open
Abstract
People with Alzheimer's disease (AD) have significantly higher rates of subclinical and overt epileptiform activity. In animal models, oligomeric Aβ amyloid is able to induce neuronal hyperexcitability even in the early phases of the disease. Such aberrant activity subsequently leads to downstream accumulation of toxic proteins, and ultimately to further neurodegeneration and neuronal silencing mediated by concomitant tau accumulation. Several neurotransmitters participate in the initial hyperexcitable state, with increased synaptic glutamatergic tone and decreased GABAergic inhibition. These changes appear to activate excitotoxic pathways and, ultimately, cause reduced long-term potentiation, increased long-term depression, and increased GABAergic inhibitory remodelling at the network level. Brain hyperexcitability has therefore been identified as a potential target for therapeutic interventions aimed at enhancing cognition, and, possibly, disease modification in the longer term. Clinical trials are ongoing to evaluate the potential efficacy in targeting hyperexcitability in AD, with levetiracetam showing some encouraging effects. Newer compounds and techniques, such as gene editing via viral vectors or brain stimulation, also show promise. Diagnostic challenges include identifying best biomarkers for measuring sub-clinical epileptiform discharges. Determining the timing of any intervention is critical and future trials will need to carefully stratify participants with respect to the phase of disease pathology.
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Affiliation(s)
- Sofia Toniolo
- Cognitive Neurology Group, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK;
- Wellcome Trust Centre for Integrative Neuroimaging, Department of Experimental Psychology, University of Oxford, Oxford OX2 6AE, UK
| | - Arjune Sen
- Oxford Epilepsy Research Group, Nuffield Department Clinical Neurosciences, John Radcliffe Hospital, Oxford OX3 9DU, UK;
| | - Masud Husain
- Cognitive Neurology Group, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK;
- Wellcome Trust Centre for Integrative Neuroimaging, Department of Experimental Psychology, University of Oxford, Oxford OX2 6AE, UK
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Implications of Oligomeric Amyloid-Beta (oAβ 42) Signaling through α7β2-Nicotinic Acetylcholine Receptors (nAChRs) on Basal Forebrain Cholinergic Neuronal Intrinsic Excitability and Cognitive Decline. J Neurosci 2020; 41:555-575. [PMID: 33239400 DOI: 10.1523/jneurosci.0876-20.2020] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 11/03/2020] [Accepted: 11/15/2020] [Indexed: 01/08/2023] Open
Abstract
Neuronal and network-level hyperexcitability is commonly associated with increased levels of amyloid-β (Aβ) and contribute to cognitive deficits associated with Alzheimer's disease (AD). However, the mechanistic complexity underlying the selective loss of basal forebrain cholinergic neurons (BFCNs), a well-recognized characteristic of AD, remains poorly understood. In this study, we tested the hypothesis that the oligomeric form of amyloid-β (oAβ42), interacting with α7-containing nicotinic acetylcholine receptor (nAChR) subtypes, leads to subnucleus-specific alterations in BFCN excitability and impaired cognition. We used single-channel electrophysiology to show that oAβ42 activates both homomeric α7- and heteromeric α7β2-nAChR subtypes while preferentially enhancing α7β2-nAChR open-dwell times. Organotypic slice cultures were prepared from male and female ChAT-EGFP mice, and current-clamp recordings obtained from BFCNs chronically exposed to pathophysiologically relevant level of oAβ42 showed enhanced neuronal intrinsic excitability and action potential firing rates. These resulted from a reduction in action potential afterhyperpolarization and alterations in the maximal rates of voltage change during spike depolarization and repolarization. These effects were observed in BFCNs from the medial septum diagonal band and horizontal diagonal band, but not the nucleus basalis. Last, aged male and female APP/PS1 transgenic mice, genetically null for the β2 nAChR subunit gene, showed improved spatial reference memory compared with APP/PS1 aged-matched littermates. Combined, these data provide a molecular mechanism supporting a role for α7β2-nAChR in mediating the effects of oAβ42 on excitability of specific populations of cholinergic neurons and provide a framework for understanding the role of α7β2-nAChR in oAβ42-induced cognitive decline.
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25
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Koulousakis P, Andrade P, Visser-Vandewalle V, Sesia T. The Nucleus Basalis of Meynert and Its Role in Deep Brain Stimulation for Cognitive Disorders: A Historical Perspective. J Alzheimers Dis 2020; 69:905-919. [PMID: 31104014 DOI: 10.3233/jad-180133] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The nucleus basalis of Meynert (nbM) was first described at the end of the 19th century and named after its discoverer, Theodor Meynert. The nbM contains a large population of cholinergic neurons that project their axons to the entire cortical mantle, the olfactory tubercle, and the amygdala. It has been functionally associated with the control of attention and maintenance of arousal, both key functions for appropriate learning and memory formation. This structure is well-conserved across vertebrates, although its degree of organization varies between species. Since early in the investigation of its functional and pathological significance, its degeneration has been linked to various major neuropsychiatric disorders. For instance, Lewy bodies, a hallmark in the diagnosis of Parkinson's disease, were originally described in the nbM. Since then, its involvement in other Lewy body and dementia-related disorders has been recognized. In the context of recent positive outcomes following nbM deep brain stimulation in subjects with dementia-associated disorders, we review the literature from an historical perspective focusing on how the nbM came into focus as a promising therapeutic option for patients with Alzheimer's disease. Moreover, we will discuss what is needed to further develop and widely implement this approach as well as examine novel medical indications for which nbM deep brain stimulation may prove beneficial.
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Affiliation(s)
- Philippos Koulousakis
- Department of Stereotactic and Functional Neurosurgery, University Hospital of Cologne, Germany.,European Graduate School of Neuroscience, Maastricht, The Netherlands
| | - Pablo Andrade
- Department of Neurosurgery, University Hospital of Cologne, Germany.,European Graduate School of Neuroscience, Maastricht, The Netherlands
| | - Veerle Visser-Vandewalle
- Department of Stereotactic and Functional Neurosurgery, University Hospital of Cologne, Germany.,European Graduate School of Neuroscience, Maastricht, The Netherlands
| | - Thibaut Sesia
- Department of Stereotactic and Functional Neurosurgery, University Hospital of Cologne, Germany.,European Graduate School of Neuroscience, Maastricht, The Netherlands
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26
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Bono F, Mutti V, Fiorentini C, Missale C. Dopamine D3 Receptor Heteromerization: Implications for Neuroplasticity and Neuroprotection. Biomolecules 2020; 10:biom10071016. [PMID: 32659920 PMCID: PMC7407647 DOI: 10.3390/biom10071016] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/06/2020] [Accepted: 07/08/2020] [Indexed: 12/14/2022] Open
Abstract
The dopamine (DA) D3 receptor (D3R) plays a pivotal role in the control of several functions, including motor activity, rewarding and motivating behavior and several aspects of cognitive functions. Recently, it has been reported that the D3R is also involved in the regulation of neuronal development, in promoting structural plasticity and in triggering key intracellular events with neuroprotective potential. A new role for D3R-dependent neurotransmission has thus been proposed both in preserving DA neuron homeostasis in physiological conditions and in preventing pathological alterations that may lead to neurodegeneration. Interestingly, there is evidence that nicotinic acetylcholine receptors (nAChR) located on DA neurons also provide neurotrophic support to DA neurons, an effect requiring functional D3R and suggesting the existence of a positive cross-talk between these receptor systems. Increasing evidence suggests that, as with the majority of G protein-coupled receptors (GPCR), the D3R directly interacts with other receptors to form new receptor heteromers with unique functional and pharmacological properties. Among them, we recently identified a receptor heteromer containing the nAChR and the D3R as the molecular effector of nicotine-mediated neurotrophic effects. This review summarizes the functional and pharmacological characteristics of D3R, including the capability to form active heteromers as pharmacological targets for specific neurodegenerative disorders. In particular, the molecular and functional features of the D3R-nAChR heteromer will be especially discussed since it may represent a possible key etiologic effector for DA-related pathologies, such as Parkinson’s disease (PD), and a target for drug design.
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Affiliation(s)
- Federica Bono
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy; (V.M.); (C.F.); (C.M.)
- Correspondence: ; Tel.: +39-0303717506
| | - Veronica Mutti
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy; (V.M.); (C.F.); (C.M.)
| | - Chiara Fiorentini
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy; (V.M.); (C.F.); (C.M.)
| | - Cristina Missale
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy; (V.M.); (C.F.); (C.M.)
- “C. Golgi” Women Health Center, University of Brescia, 25123 Brescia, Italy
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27
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Progress in nicotinic receptor structural biology. Neuropharmacology 2020; 171:108086. [PMID: 32272141 DOI: 10.1016/j.neuropharm.2020.108086] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 03/31/2020] [Indexed: 02/07/2023]
Abstract
Here we begin by briefly reviewing landmark structural studies on the nicotinic acetylcholine receptor. We highlight challenges that had to be overcome to push through resolution barriers, then focus on what has been gleaned in the past few years from crystallographic and single particle cryo-EM studies of different nicotinic receptor subunit assemblies and ligand complexes. We discuss insights into ligand recognition, ion permeation, and allosteric gating. We then highlight some foundational aspects of nicotinic receptor structural biology that remain unresolved and are areas ripe for future exploration. This article is part of the special issue on 'Contemporary Advances in Nicotine Neuropharmacology'.
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28
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Donat CK, Hansen HH, Hansen HD, Mease RC, Horti AG, Pomper MG, L’Estrade ET, Herth MM, Peters D, Knudsen GM, Mikkelsen JD. In Vitro and In Vivo Characterization of Dibenzothiophene Derivatives [ 125I]Iodo-ASEM and [ 18F]ASEM as Radiotracers of Homo- and Heteromeric α7 Nicotinic Acetylcholine Receptors. Molecules 2020; 25:molecules25061425. [PMID: 32245032 PMCID: PMC7144377 DOI: 10.3390/molecules25061425] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 02/25/2020] [Accepted: 02/27/2020] [Indexed: 12/18/2022] Open
Abstract
The α7 nicotinic acetylcholine receptor (α7 nAChR) is involved in several cognitive and physiologic processes; its expression levels and patterns change in neurologic and psychiatric diseases, such as schizophrenia and Alzheimer’s disease, which makes it a relevant drug target. Development of selective radioligands is important for defining binding properties and occupancy of novel molecules targeting the receptor. We tested the in vitro binding properties of [125I]Iodo-ASEM [(3-(1,4-diazabycyclo[3.2.2]nonan-4-yl)-6-(125I-iododibenzo[b,d]thiopentene 5,5-dioxide)] in the mouse, rat and pig brain using autoradiography. The in vivo binding properties of [18F]ASEM were investigated using positron emission tomography (PET) in the pig brain. [125I]Iodo-ASEM showed specific and displaceable high affinity (~1 nM) binding in mouse, rat, and pig brain. Binding pattern overlapped with [125I]α-bungarotoxin, specific binding was absent in α7 nAChR gene-deficient mice and binding was blocked by a range of α7 nAChR orthosteric modulators in an affinity-dependent order in the pig brain. Interestingly, relative to the wild-type, binding in β2 nAChR gene-deficient mice was lower for [125I]Iodo-ASEM (58% ± 2.7%) than [125I]α-bungarotoxin (23% ± 0.2%), potentially indicating different binding properties to heteromeric α7β2 nAChR. [18F]ASEM PET in the pig showed high brain uptake and reversible tracer kinetics with a similar spatial distribution as previously reported for α7 nAChR. Blocking with SSR-180,711 resulted in a significant decrease in [18F]ASEM binding. Our findings indicate that [125I]Iodo-ASEM allows sensitive and selective imaging of α7 nAChR in vitro, with better signal-to-noise ratio than previous tracers. Preliminary data of [18F]ASEM in the pig brain demonstrated principal suitable kinetic properties for in vivo quantification of α7 nAChR, comparable to previously published data.
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Affiliation(s)
- Cornelius K. Donat
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (H.H.H.); (H.D.H.); (E.T.L.); (G.M.K.)
- Department of Brain Sciences, Imperial College London, London W12 0 LS, UK
- Correspondence: (C.K.D.); (J.D.M.); Tel.: +45-40205378 (J.D.M)
| | - Henrik H. Hansen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (H.H.H.); (H.D.H.); (E.T.L.); (G.M.K.)
| | - Hanne D. Hansen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (H.H.H.); (H.D.H.); (E.T.L.); (G.M.K.)
| | - Ronnie C. Mease
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (R.C.M.); (A.G.H.); (M.G.P.)
| | - Andrew G. Horti
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (R.C.M.); (A.G.H.); (M.G.P.)
| | - Martin G. Pomper
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; (R.C.M.); (A.G.H.); (M.G.P.)
| | - Elina T. L’Estrade
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (H.H.H.); (H.D.H.); (E.T.L.); (G.M.K.)
- Department of Drug Design and Pharmacology, University of Copenhagen, Jagtvej 162, 2100 Copenhagen, Denmark;
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Matthias M. Herth
- Department of Drug Design and Pharmacology, University of Copenhagen, Jagtvej 162, 2100 Copenhagen, Denmark;
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | | | - Gitte M. Knudsen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (H.H.H.); (H.D.H.); (E.T.L.); (G.M.K.)
| | - Jens D. Mikkelsen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark; (H.H.H.); (H.D.H.); (E.T.L.); (G.M.K.)
- Correspondence: (C.K.D.); (J.D.M.); Tel.: +45-40205378 (J.D.M)
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29
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Tarasenko O, Voytenko S, Koval L, Lykhmus O, Kalashnyk O, Skok M. Unusual properties of α7 nicotinic acetylcholine receptor ion channels in B lymphocyte-derived SP-2/0 cells. Int Immunopharmacol 2020; 82:106373. [PMID: 32163855 DOI: 10.1016/j.intimp.2020.106373] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 02/25/2020] [Accepted: 03/02/2020] [Indexed: 12/30/2022]
Abstract
This study demonstrates the presence of α7 nicotinic acetylcholine receptors (nAChR) in B lymphocyte-derived SP-2/0 cells by means of flow cytometry and immunocytochemistry. According to lectin and sandwich ELISA, the α7 subunits expressed in SP-2/0 cells are more glycosylated compared to those expressed in the brain or normal B lymphocytes and are combined with β2 subunits. At zero and negative pipette potentials, either acetylcholine or α7-specific agonist PNU282987 stimulated the ion channel activity in SP-2/0 cells revealed by single channel patch-clamp recordings. The conductivity was within the range of 19 to 39 pS and reversal potential was between -17 mV and +28 mV, the currents were potentiated by α7-specific positive allosteric modulator PNU120596 and were partially blocked by α7-specific antagonist methyllicaconitine (MLA). However, they were oriented downwards suggesting that the channels mediated the cation outflux rather than influx. As shown by Ca2+ imaging studies, PNU282987 did not stimulate immediate Ca2+ influx into SP-2/0 cells. Instead, Ca2+ influx through Ca-release-activated channels (CRACs) was observed within minutes after either PNU282987 or MLA application. It is concluded that SP-2/0 express α7β2 nAChRs, which mediate the cation outflux under negative pipette potentials applied, possibly, due to depolarized membrane or negative surface charge formed by carbohydrate residues. In addition, α7β2 nAChRs may influence CRACs in ion-independent way.
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Affiliation(s)
| | - Sergiy Voytenko
- Bogomoletz Institute of Physiology, 4, Bogomoletz Str, 01024 Kyiv, Ukraine
| | - Lyudmyla Koval
- Palladin Institute of Biochemistry, 9, Leontovycha Str., 01030 Kyiv, Ukraine.
| | - Olena Lykhmus
- Palladin Institute of Biochemistry, 9, Leontovycha Str., 01030 Kyiv, Ukraine
| | - Olena Kalashnyk
- Palladin Institute of Biochemistry, 9, Leontovycha Str., 01030 Kyiv, Ukraine
| | - Maryna Skok
- Palladin Institute of Biochemistry, 9, Leontovycha Str., 01030 Kyiv, Ukraine.
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30
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Zulfiqar S, Garg P, Nieweg K. Contribution of astrocytes to metabolic dysfunction in the Alzheimer's disease brain. Biol Chem 2020; 400:1113-1127. [PMID: 31188740 DOI: 10.1515/hsz-2019-0140] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 05/28/2019] [Indexed: 11/15/2022]
Abstract
Historically considered as accessory cells to neurons, there is an increasing interest in the role of astrocytes in normal and pathological conditions. Astrocytes are involved in neurotransmitter recycling, antioxidant supply, ion buffering and neuroinflammation, i.e. a lot of the same pathways that go astray in Alzheimer's disease (AD). AD remains the leading cause of dementia in the elderly, one for which there is still no cure. Efforts in AD drug development have largely focused on treating neuronal pathologies that appear relatively late in the disease. The neuroenergetic hypothesis, however, focuses on the early event of glucose hypometabolism in AD, where astrocytes play a key role, caused by an imbalanced neuron-astrocyte lactate shuttle. This further results in a state of oxidative stress and neuroinflammation, thereby compromising the integrity of astrocyte-neuron interaction. Compromised astrocytic energetics also enhance amyloid generation, further increasing the severity of the disease. Additionally, apolipoprotein E (APOE), the major genetic risk factor for AD, is predominantly secreted by astrocytes and plays a critical role in amyloid clearance and regulates glucose metabolism in an amyloid-independent manner. Thus, boosting the neuroprotective properties of astrocytes has potential applications in delaying the onset and progression of AD. This review explores how the metabolic dysfunction arising from astrocytes acts as a trigger for the development of AD.
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Affiliation(s)
- Shadaan Zulfiqar
- Institute for Pharmacology and Clinical Pharmacy, Philipps University, Karl-von-Frisch Strasse, Marburg D-35043, Germany.,Marburg Center for Mind, Brain and Behavior, Philipps University, Marburg, Germany
| | - Pretty Garg
- Institute for Pharmacology and Clinical Pharmacy, Philipps University, Karl-von-Frisch Strasse, Marburg D-35043, Germany.,Marburg Center for Mind, Brain and Behavior, Philipps University, Marburg, Germany.,Institute for Neuro and Sensory Physiology, Heinrich Heine University, Düsseldorf D-40225, Germany
| | - Katja Nieweg
- Institute for Pharmacology and Clinical Pharmacy, Philipps University, Karl-von-Frisch Strasse, Marburg D-35043, Germany.,Marburg Center for Mind, Brain and Behavior, Philipps University, Marburg, Germany
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31
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Sun JL, Stokoe SA, Roberts JP, Sathler MF, Nip KA, Shou J, Ko K, Tsunoda S, Kim S. Co-activation of selective nicotinic acetylcholine receptors is required to reverse beta amyloid-induced Ca 2+ hyperexcitation. Neurobiol Aging 2019; 84:166-177. [PMID: 31629115 DOI: 10.1016/j.neurobiolaging.2019.09.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Revised: 08/27/2019] [Accepted: 09/13/2019] [Indexed: 12/20/2022]
Abstract
Beta-amyloid (Aβ) peptide accumulation has long been implicated in the pathogenesis of Alzheimer's disease (AD). Hippocampal network hyperexcitability in the early stages of the disease leads to increased epileptiform activity and eventually cognitive decline. We found that acute application of 250 nM soluble Aβ42 oligomers increased Ca2+ activity in hippocampal neurons in parallel with a significant decrease in activity in Aβ42-treated interneurons. A potential target of Aβ42 is the nicotinic acetylcholine receptor (nAChR). Three major subtypes of nAChRs (α7, α4β2, and α3β4) have been reported in the human hippocampus. Simultaneous inhibition of both α7 and α4β2 nAChRs mimicked the Aβ42 effects on both excitatory and inhibitory neurons. However, inhibition of all 3 subtypes showed the opposite effect. Importantly, simultaneous activation of α7 and α4β2 nAChRs was required to reverse Aβ42-induced neuronal hyperexcitation. We suggest co-activation of α7 and α4β2 nAChRs is required to reverse Aβ42-induced Ca2+ hyperexcitation.
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Affiliation(s)
- Julianna L Sun
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA; Molecular, Cellular and Integrative Neurosciences Program, Fort Collins, CO, USA
| | - Sarah A Stokoe
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA; Molecular, Cellular and Integrative Neurosciences Program, Fort Collins, CO, USA
| | - Jessica P Roberts
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA; Molecular, Cellular and Integrative Neurosciences Program, Fort Collins, CO, USA
| | - Matheus F Sathler
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Kaila A Nip
- Cellular and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO, USA
| | - Jiayi Shou
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Kaitlyn Ko
- Poudre High School, Fort Collins, CO, USA
| | - Susan Tsunoda
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA; Molecular, Cellular and Integrative Neurosciences Program, Fort Collins, CO, USA
| | - Seonil Kim
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA; Molecular, Cellular and Integrative Neurosciences Program, Fort Collins, CO, USA; Cellular and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO, USA.
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32
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Rodríguez-Soacha DA, Scheiner M, Decker M. Multi-target-directed-ligands acting as enzyme inhibitors and receptor ligands. Eur J Med Chem 2019; 180:690-706. [PMID: 31401465 DOI: 10.1016/j.ejmech.2019.07.040] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 07/04/2019] [Accepted: 07/11/2019] [Indexed: 12/20/2022]
Abstract
In this review, we present the latest advances in the field of multi-target-directed ligand (MTDL) design for the treatment of various complex pathologies of multifactorial origin. In particular, latest findings in the field of MTDL design targeting both an enzyme and a receptor are presented for different diseases such as Alzheimer's disease (AD), depression, addiction, glaucoma, non-alcoholic steatohepatitis and pain and inflammation. The ethology of the diseases is briefly described, with special emphasis on how the MTDL can evolve into novel therapies that replace the classic pharmacological dogma "one target one disease". Considering the current needs for therapy adherence improvement, it is exposed as from the medicinal chemistry, different molecular scaffolds are studied. With the use of structure activity relationship studies and molecular optimization, new hybrid molecules are generated with improved biological properties acting at two biologically very distinct targets.
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Affiliation(s)
- Diego Alejandro Rodríguez-Soacha
- Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy and Food Chemistry, Julius Maximilian University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Matthias Scheiner
- Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy and Food Chemistry, Julius Maximilian University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Michael Decker
- Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy and Food Chemistry, Julius Maximilian University of Würzburg, Am Hubland, 97074, Würzburg, Germany.
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33
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Toxins for decoding interface selectivity in nicotinic acetylcholine receptors. Biochem J 2019; 476:1515-1520. [PMID: 31138769 DOI: 10.1042/bcj20190255] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 04/29/2019] [Accepted: 05/03/2019] [Indexed: 01/25/2023]
Abstract
Nicotinic acetylcholine receptors (nAChRs) are pentameric ligand-gated ion channels that play crucial roles in neurotransmission and regulate complex processes in brain functions, including anxiety, learning and memory, food intake, drug addiction, cognition and nociception. To perform these and other functions, a diverse array of nAChR subtypes are generated by homomeric or heteromeric assembly of 17 homologous nAChR subunits. Agonists, acetylcholine and nicotine, bind to the interface formed between two α subunits and between α and non-α subunits to activate the nAChR and allow cation influx. The diversity of subunit interfaces determines the channel properties, the responses to different agonists/antagonists, desensitization and downstream signaling and thus, define specialized properties and functions. Over the last several decades, snake venom neurotoxins have contributed to the purification, localization and characterization of molecular details of various nAChRs. Utkin et al. have described the purification and characterization of αδ-bungarotoxins, a novel class of neurotoxins in a recent paper published in the Biochemical Journal [Biochem. J. (2019) 476, 1285-1302]. These toxins from Bungarus candidus venom preferably bind to α-δ site with two orders of magnitude higher affinity compared with α-γ or α-ε sites. The subtle changes in the structure of αδ-bungarotoxins led to variation in interface selectivity. Such new classes of antagonists will offer us great opportunity to delineate the pharmacophores and design new highly selective antagonists. Thus, their findings provide new impetus to re-evaluate molecular details of pharmacological properties of α-neurotoxins with careful consideration towards subtype-, interface- and species-selectivity.
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34
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Activation of α7 nicotinic acetylcholine receptor alleviates Aβ1-42-induced neurotoxicity via downregulation of p38 and JNK MAPK signaling pathways. Neurochem Int 2018; 120:238-250. [DOI: 10.1016/j.neuint.2018.09.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 08/23/2018] [Accepted: 09/09/2018] [Indexed: 01/08/2023]
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35
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Solari N, Hangya B. Cholinergic modulation of spatial learning, memory and navigation. Eur J Neurosci 2018; 48:2199-2230. [PMID: 30055067 PMCID: PMC6174978 DOI: 10.1111/ejn.14089] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 06/25/2018] [Accepted: 07/23/2018] [Indexed: 01/02/2023]
Abstract
Spatial learning, including encoding and retrieval of spatial memories as well as holding spatial information in working memory generally serving navigation under a broad range of circumstances, relies on a network of structures. While central to this network are medial temporal lobe structures with a widely appreciated crucial function of the hippocampus, neocortical areas such as the posterior parietal cortex and the retrosplenial cortex also play essential roles. Since the hippocampus receives its main subcortical input from the medial septum of the basal forebrain (BF) cholinergic system, it is not surprising that the potential role of the septo-hippocampal pathway in spatial navigation has been investigated in many studies. Much less is known of the involvement in spatial cognition of the parallel projection system linking the posterior BF with neocortical areas. Here we review the current state of the art of the division of labour within this complex 'navigation system', with special focus on how subcortical cholinergic inputs may regulate various aspects of spatial learning, memory and navigation.
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Affiliation(s)
- Nicola Solari
- Lendület Laboratory of Systems NeuroscienceDepartment of Cellular and Network NeurobiologyInstitute of Experimental MedicineHungarian Academy of SciencesBudapestHungary
| | - Balázs Hangya
- Lendület Laboratory of Systems NeuroscienceDepartment of Cellular and Network NeurobiologyInstitute of Experimental MedicineHungarian Academy of SciencesBudapestHungary
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36
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Nielsen BE, Minguez T, Bermudez I, Bouzat C. Molecular function of the novel α7β2 nicotinic receptor. Cell Mol Life Sci 2018; 75:2457-2471. [PMID: 29313059 PMCID: PMC11105712 DOI: 10.1007/s00018-017-2741-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 11/30/2017] [Accepted: 12/27/2017] [Indexed: 01/03/2023]
Abstract
The α7 nicotinic receptor is a promising drug target for neurological and inflammatory disorders. Although it is the homomeric member of the family, a novel α7β2 heteromeric receptor has been discovered. To decipher the functional contribution of the β2 subunit, we generated heteromeric receptors with fixed stoichiometry by two different approaches comprising concatenated and unlinked subunits. Receptors containing up to three β2 subunits are functional. As the number of β2 subunits increases in the pentameric arrangement, the durations of channel openings and activation episodes increase progressively probably due to decreased desensitization. The prolonged activation episodes conform the kinetic signature of α7β2 and may have an impact on neuronal excitability. For activation of α7β2 receptors, an α7/α7 binding-site interface is required, thus indicating that the three β2 subunits are located consecutively in the pentameric arrangement. α7-positive allosteric modulators (PAMs) are emerging as novel therapeutic drugs. The presence of β2 in the pentamer affects neither type II PAM potentiation nor activation by an allosteric agonist whereas it impairs type I PAM potentiation. This first single-channel study provides fundamental basis required to decipher the role and function of the novel α7β2 receptor and opens doors to develop selective therapeutic drugs.
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Affiliation(s)
- Beatriz E Nielsen
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas y Técnicas (UNS-CONICET), 8000, Bahía Blanca, Argentina
| | - Teresa Minguez
- Department of Medical and Biological Sciences, Oxford Brookes University, Oxford, OX3 0BP, UK
| | - Isabel Bermudez
- Department of Medical and Biological Sciences, Oxford Brookes University, Oxford, OX3 0BP, UK
| | - Cecilia Bouzat
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas y Técnicas (UNS-CONICET), 8000, Bahía Blanca, Argentina.
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α-Conotoxins to explore the molecular, physiological and pathophysiological functions of neuronal nicotinic acetylcholine receptors. Neurosci Lett 2017; 679:24-34. [PMID: 29199094 DOI: 10.1016/j.neulet.2017.11.063] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 11/28/2017] [Accepted: 11/29/2017] [Indexed: 12/22/2022]
Abstract
The vast diversity of neuronal nicotinic acetylcholine subunits expressed in the central and peripheral nervous systems, as well as in non-neuronal tissues, constitutes a formidable challenge for researchers and clinicians to decipher the role of particular subtypes, including complex subunit associations, in physiological and pathophysiological functions. Many natural products target the nAChRs, but there is no richer source of nicotinic ligands than the venom of predatory gastropods known as cone snails. Indeed, every single species of cone snail was shown to produce at least one type of such α-conotoxins. These tiny peptides (10-25 amino acids), constrained by disulfide bridges, proved to be unvaluable tools to investigate the structure and function of nAChRs, some of them having also therapeutic potential. In this review, we provide a recent update on the pharmacology and subtype specificity of several major α-conotoxins.
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38
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Hone AJ, McIntosh JM. Nicotinic acetylcholine receptors in neuropathic and inflammatory pain. FEBS Lett 2017; 592:1045-1062. [PMID: 29030971 DOI: 10.1002/1873-3468.12884] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 09/22/2017] [Accepted: 10/05/2017] [Indexed: 01/11/2023]
Abstract
Nicotinic acetylcholine receptors (nAChRs) are actively being investigated as therapeutic targets for the treatment of pain and inflammation, but despite more than 30 years of research, there are currently no FDA-approved analgesics that are specific for these receptors. Much of the initial research effort focused on the α4β2 nAChR subtype, but more recently, additional subtypes have been identified as promising new leads and include α6β4, α7, and α9-containing nAChRs. This Review will focus on the distribution of these nAChRs in the cell types involved in neuropathic pain and inflammation and the activity of currently available nicotinic ligands.
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Affiliation(s)
- Arik J Hone
- Department of Biology, University of Utah, Salt Lake City, UT, USA
| | - J Michael McIntosh
- Department of Biology, University of Utah, Salt Lake City, UT, USA.,Department of Psychiatry, University of Utah, Salt Lake City, UT, USA.,George E. Whalen Veterans Affairs Medical Center, Salt Lake City, UT, USA
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Liu Q, Whiteaker P, Morley BJ, Shi FD, Lukas RJ. Distinctive Roles for α7*- and α9*-Nicotinic Acetylcholine Receptors in Inflammatory and Autoimmune Responses in the Murine Experimental Autoimmune Encephalomyelitis Model of Multiple Sclerosis. Front Cell Neurosci 2017; 11:287. [PMID: 29018331 PMCID: PMC5615207 DOI: 10.3389/fncel.2017.00287] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 09/01/2017] [Indexed: 12/11/2022] Open
Abstract
Previous studies have demonstrated immunosuppressive and anti-inflammatory effects of nicotine, including in the experimental autoimmune encephalomyelitis (EAE) model in mice of some forms of multiple sclerosis (MS). Other studies using knock-out (KO) mice have implicated nicotinic acetylcholine (ACh) receptors containing α7, α9, or β2 subunits (α7*-, α9*- or β2*-nAChR) in different, disease-exacerbating or disease-ameliorating processes. These outcomes are in harmony with gene expression analyses showing nAChR subunit mRNA in many classes of immune system cell types. Consistent with influences on disease status, predictable effects of nAChR subunit (and subtype) KO, or of nicotine exposure, are seen on immune cell numbers and distribution and on cytokine levels or other markers of immunity, inflammation, demyelination, and axonal degradation. Providing support for our hypotheses about distinctive roles for nAChR subtypes in EAE, here we have used direct and adoptive EAE induction and a nAChR subunit gene double knock-out (DKO) strategy. Immune cell expression of nAChR α9 subunits as protein is demonstrated by immunostaining of isolated CD4+, CD8+, CD11b+ and CD11c+ cells from wild-type (WT) mice, but not in cells from nAChR α9 subunit KO animals. Nicotine exposure is protective against directly-induced EAE in WT or α7/α9 DKO animals relative to effects seen in WT/vehicle-treated mice, but, remarkably, EAE is exacerbated in vehicle-treated α7/α9 DKO mice. Brain lesion volume and intra-cranial inflammatory activity similarly are higher in DKO/vehicle than in WT/vehicle-treated animals, although nicotine’s protective effects are seen in each instance. By contrast, in adoptive transfer studies, disease severity is attenuated and disease onset is delayed in recipients of splenocytes from WT animals treated with nicotine rather than with vehicle. Moreover, protection as seen in nicotine-treated WT animals is the same in recipients of splenocytes from nAChR α7/α9 DKO mice irrespective of their exposure to nicotine or vehicle. When combined with previous observations, these findings are consistent with disease exacerbation (or even induction) being mediated at least in part via α9*-nAChR in peripheral immune cells. They also suggest protective roles of central nervous system (CNS) α7*-nAChR. The results suggest that both α7*- and α9*-nAChR are potential targets of therapeutic ligands to modulate inflammation and autoimmunity.
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Affiliation(s)
- Qiang Liu
- Division of Neurobiology, Barrow Neurological InstitutePhoenix, AZ, United States
| | - Paul Whiteaker
- Division of Neurobiology, Barrow Neurological InstitutePhoenix, AZ, United States
| | | | - Fu-Dong Shi
- Division of Neurobiology, Barrow Neurological InstitutePhoenix, AZ, United States
| | - Ronald J Lukas
- Division of Neurobiology, Barrow Neurological InstitutePhoenix, AZ, United States
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Borniger JC, Don RF, Zhang N, Boyd RT, Nelson RJ. Enduring effects of perinatal nicotine exposure on murine sleep in adulthood. Am J Physiol Regul Integr Comp Physiol 2017. [PMID: 28637659 DOI: 10.1152/ajpregu.00156.2017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The long-term consequences of early life nicotine exposure are poorly defined. Approximately 8-10% of women report smoking during pregnancy, and this may promote aberrant development in the offspring. To this end, we investigated potential enduring effects of perinatal nicotine exposure on murine sleep and affective behaviors in adulthood (~13-15 wk of age) in C57Bl6j mice. Mothers received a water bottle containing 200 µg/ml nicotine bitartrate dihydrate in 2% wt/vol saccharin or pH-matched 2% saccharin with 0.2% (vol/vol) tartaric acid throughout pregnancy and before weaning. Upon reaching adulthood, offspring were tested in the open field and elevated plus maze, as well as the forced swim and sucrose anhedonia tests. Nicotine-exposed male (but not female) mice had reduced mobility in the open field, but no differences were observed in anxiety-like or depressive-like responses. Upon observing this male-specific phenotype, we further assessed sleep-wake states via wireless EEG/EMG telemetry. Following baseline recording, we assessed whether mice exposed to nicotine altered their homeostatic response to 5 h of total sleep deprivation and whether nicotine influenced responses to a powerful somnogen [i.e., lipopolysaccharides (LPS)]. Males exposed to perinatal nicotine decreased the percent time spent awake and increased time in non-rapid eye movement (NREM) sleep, without changes to REM sleep. Nicotine-exposed males also displayed exaggerated responses (increased time asleep and NREM spectral power) to sleep deprivation. Nicotine-exposed animals additionally had blunted EEG slow-wave responses to LPS administration. Together, our data suggest that perinatal nicotine exposure has long-lasting effects on normal sleep and homeostatic sleep processes into adulthood.
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Affiliation(s)
- Jeremy C Borniger
- Department of Neuroscience and Behavioral Neuroendocrinology Group, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - Reuben F Don
- Department of Neuroscience and Behavioral Neuroendocrinology Group, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - Ning Zhang
- Department of Neuroscience and Behavioral Neuroendocrinology Group, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - R Thomas Boyd
- Department of Neuroscience and Behavioral Neuroendocrinology Group, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - Randy J Nelson
- Department of Neuroscience and Behavioral Neuroendocrinology Group, The Ohio State University Wexner Medical Center, Columbus, Ohio
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Callahan PM, Bertrand D, Bertrand S, Plagenhoef MR, Terry AV. Tropisetron sensitizes α7 containing nicotinic receptors to low levels of acetylcholine in vitro and improves memory-related task performance in young and aged animals. Neuropharmacology 2017; 117:422-433. [PMID: 28259598 DOI: 10.1016/j.neuropharm.2017.02.025] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 02/06/2017] [Accepted: 02/25/2017] [Indexed: 01/02/2023]
Abstract
Tropisetron, a 5-HT3 receptor antagonist commonly prescribed for chemotherapy-induced nausea and vomiting also exhibits high affinity, partial agonist activity at α7 nicotinic acetylcholine receptors (α7 nAChRs). α7 nAChRs are considered viable therapeutic targets for neuropsychiatric disorders such as Alzheimer's disease (AD). Here we further explored the nAChR pharmacology of tropisetron to include the homomeric α7 nAChR and recently characterized heteromeric α7β2 nAChR (1:10 ratio) and we evaluated its cognitive effects in young and aged animals. Electrophysiological studies on human nAChRs expressed in Xenopus oocytes confirmed the partial agonist activity of tropisetron at α7 nAChRs (EC50 ∼2.4 μM) with a similar effect at α7β2 nAChRs (EC50 ∼1.5 μM). Moreover, currents evoked by irregular pulses of acetylcholine (40 μM) at α7 and α7β2 nAChRs were enhanced during sustained exposure to low concentrations of tropisetron (10 and 30 nM) indicative of a "priming" or co-agonist effect. Tropisetron (0.1-10 mg/kg) improved novel object recognition performance in young Sprague-Dawley rats and in aged Fischer rats. In aged male and female rhesus monkeys, tropisetron (0.03-1 mg/kg) produced a 17% increase from baseline levels in delayed match to sample long delay accuracy while combination of non-effective doses of donepezil (0.1 mg/kg) and tropisetron (0.03 and 0.1 mg/kg) produced a 24% change in accuracy. Collectively, these animal experiments indicate that tropisetron enhances cognition and has the ability to improve the effective dose range of currently prescribed AD therapy (donepezil). Moreover, these effects may be explained by tropisetron's ability to sensitize α7 containing nAChRs to low levels of acetylcholine.
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Affiliation(s)
- Patrick M Callahan
- Department of Pharmacology and Toxicology, Augusta University, Augusta, GA 30912, United States.
| | - Daniel Bertrand
- HiQScreen Sàrl, 6, rte de Compois, 1222 Vésenaz, Geneva, Switzerland
| | - Sonia Bertrand
- HiQScreen Sàrl, 6, rte de Compois, 1222 Vésenaz, Geneva, Switzerland
| | - Marc R Plagenhoef
- Department of Pharmacology and Toxicology, Augusta University, Augusta, GA 30912, United States
| | - Alvin V Terry
- Department of Pharmacology and Toxicology, Augusta University, Augusta, GA 30912, United States
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Shi S, Liang D, Bao M, Xie Y, Xu W, Wang L, Wang Z, Qiao Z. Gx-50 Inhibits Neuroinflammation via α7 nAChR Activation of the JAK2/STAT3 and PI3K/AKT Pathways. J Alzheimers Dis 2016; 50:859-71. [PMID: 26836188 DOI: 10.3233/jad-150963] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Recent studies have revealed that the α7 nicotinic acetylcholine receptor (α7 nAChR) is a critical link between inflammation and neurodegeneration, which is closely associated with Alzheimer's disease (AD). The JAK2/STAT3 and PI3K/AKT signaling pathways contribute to the neuroprotective and anti-inflammatory effects of α7nAChR. Our previous studies have shown that treatment with gx-50 improves cognitive function and is neuroprotective. Here, we investigated the effect of gx-50 on α7 nAChR and Aβ-induced inflammation in microglia. First, the binding affinity of gx-50 to α7 nAChR was examined using the fluorescence-based Octet RED system, and the expression of α7 nAChR was detected using real-time PCR and western blotting. We also investigated downstream events of α7 nAChR activity, including the translocation of p-STAT3 and the phosphorylation of JAK2, STAT3, PI3K, and AKT. Finally, the effect of gx-50 on Aβ-induced inflammation via α7 nAChR-mediated signaling pathways was investigated using cytokine assays. The results showed that gx-50 is able to act as a specific ligand to activate α7 nAChR, which then upregulates the JAK2/STAT3 and PI3K/AKT signaling pathways to inhibit the secretions of pro-inflammatory cytokines, such as IL-1β. In conclusion, the results suggest that gx-50 could inhibit the Aβ-induced inflammatory response in microglia via α7 nAChR activity, which might be a successful therapeutic target against AD.
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Lombardo S, Catteau J, Besson M, Maskos U. A role for β2* nicotinic receptors in a model of local amyloid pathology induced in dentate gyrus. Neurobiol Aging 2016; 46:221-34. [DOI: 10.1016/j.neurobiolaging.2016.06.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 05/22/2016] [Accepted: 06/09/2016] [Indexed: 12/22/2022]
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Zhao P, Yang X, Yang L, Li M, Wood K, Liu Q, Zhu X. Neuroprotective effects of fingolimod in mouse models of Parkinson's disease. FASEB J 2016; 31:172-179. [PMID: 27671228 DOI: 10.1096/fj.201600751r] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/16/2016] [Indexed: 02/04/2023]
Abstract
Parkinson's disease (PD) is characterized by a progressive loss of dopaminergic neurons with limited treatment options. Emerging evidence shows that FTY720 protects against neural injury via modulation of the sphingosine-1-phosphate 1 receptor (S1PR1). However, it remains unclear whether FTY720 could influence neurodegeneration in PD. Therefore, the present study was designed to determine the impact of fingolimod (FTY720), a sphingosine-1-phosphate receptor (S1PR) agonist, on 2 mouse models of PD. We found that FTY720 significantly reduced the deficit of motor function, diminished the loss of tyrosine hydroxylase-positive neurons in the substantia nigra, and attenuated the decrease of striatal dopamine and metabolite levels in mice receiving 6-hydroxydopamine (6-OHDA) or rotenone to simulate PD. An S1PR1-selective antagonist, W146, blocked the neuroprotective effects of FTY720. Of note, FTY720 retained the phosphorylation of ERK, together with a decreased expression of cleaved caspase-3 in mice treated with 6-OHDA or rotenone. In vitro studies revealed that FTY720 also attenuated 6-OHDA- or rotenone-induced toxicity in SH-SY5Y cells. These findings suggest the potential of S1PR modulation as a treatment for PD.-Zhao, P., Yang, X., Yang, L., Li, M., Wood, K., Liu, Q., Zhu, X. Neuroprotective effects of fingolimod in mouse models of Parkinson's disease.
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Affiliation(s)
- Peng Zhao
- Department of Neurology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China; and
| | - Xiaoxia Yang
- Department of Neurology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China; and
| | - Liu Yang
- Department of Neurology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China; and
| | - Minshu Li
- Department of Neurology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China; and.,Division of Neurology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Kristofer Wood
- Division of Neurology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Qiang Liu
- Department of Neurology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China; and .,Division of Neurology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Xiaodong Zhu
- Department of Neurology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China; and .,Division of Neurology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
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45
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Gozen O, Nesil T, Kanit L, Koylu EO, Pogun S. Nicotinic cholinergic and dopaminergic receptor mRNA expression in male and female rats with high or low preference for nicotine. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 2016; 42:556-566. [PMID: 27428758 DOI: 10.1080/00952990.2016.1198799] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND Nicotine exerts its central actions through nicotinic acetylcholine receptors (nAChRs), which in turn regulate major neurotransmitter systems including dopamine. Nicotinic and dopaminergic systems play significant roles in physiological functions, neuropsychiatric disorders, and addiction. OBJECTIVES To evaluate possible differences in the expression of nAChR subunit and dopamine receptor (DR) mRNAs following voluntary nicotine intake. METHODS Male and female rats (n = 67) were exposed to long-term free-choice oral nicotine (24 hours/day, 6 weeks); rats with maximum and minimum nicotine preference/intake were selected. The mRNA levels of genes encoding α4,β2,α5, and α7 nAChR subunits and DR Drd1and Drd2 subtypes were evaluated in the striatum (STR), prefrontal cortex (PFC), and hippocampus using quantitative real-time polymerase chain reaction in selected rats (n = 30) and their control groups (n = 15). RESULTS In addition to baseline differences, expression changes were observed in the mRNA levels of evaluated genes in rats exposed to voluntary oral nicotine in a brain region-, sex-, and preference-related manner. Nicotine intake is correlated negatively with Chrnb2, Chrna7 and positively with Drd1 expression. In the cholinergic system, regional differences in Chnrb2 and Chrna5, sex differences in Chrna4 and Chrna5, and nicotine preference effects in the expression of all subunits except α4 were observed. Chrna5 was lower in maximum than in minimum preferring, and in male than female rats, supporting the inhibitory role of the α5 subunit in nicotine dependence. Nicotine increased Drd2 mRNA expression only in minimum preferring female rats in STR and PFC. CONCLUSION Modulation of nAChR and DR gene expression by nicotine may have clinical implications and aid drug development. Pharmaceuticals targeting the nicotinic cholinergic and dopaminergic systems might be expected to have differential efficacy that varies with the patient's sex or smoking status.
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Affiliation(s)
- Oguz Gozen
- a Center for Brain Research , Ege University , Bornova , Izmir , Turkey.,b School of Medicine Department of Physiology , Ege University , Bornova , Izmir , Turkey
| | - Tanseli Nesil
- a Center for Brain Research , Ege University , Bornova , Izmir , Turkey
| | - Lutfiye Kanit
- a Center for Brain Research , Ege University , Bornova , Izmir , Turkey.,b School of Medicine Department of Physiology , Ege University , Bornova , Izmir , Turkey
| | - Ersin O Koylu
- a Center for Brain Research , Ege University , Bornova , Izmir , Turkey.,b School of Medicine Department of Physiology , Ege University , Bornova , Izmir , Turkey
| | - Sakire Pogun
- a Center for Brain Research , Ege University , Bornova , Izmir , Turkey
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46
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Kalkman HO, Feuerbach D. Modulatory effects of α7 nAChRs on the immune system and its relevance for CNS disorders. Cell Mol Life Sci 2016; 73:2511-30. [PMID: 26979166 PMCID: PMC4894934 DOI: 10.1007/s00018-016-2175-4] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 02/25/2016] [Accepted: 03/01/2016] [Indexed: 02/08/2023]
Abstract
The clinical development of selective alpha-7 nicotinic acetylcholine receptor (α7 nAChR) agonists has hitherto been focused on disorders characterized by cognitive deficits (e.g., Alzheimer's disease, schizophrenia). However, α7 nAChRs are also widely expressed by cells of the immune system and by cells with a secondary role in pathogen defense. Activation of α7 nAChRs leads to an anti-inflammatory effect. Since sterile inflammation is a frequently observed phenomenon in both psychiatric disorders (e.g., schizophrenia, melancholic and bipolar depression) and neurological disorders (e.g., Alzheimer's disease, Parkinson's disease, and multiple sclerosis), α7 nAChR agonists might show beneficial effects in these central nervous system disorders. In the current review, we summarize information on receptor expression, the intracellular signaling pathways they modulate and reasons for receptor dysfunction. Information from tobacco smoking, vagus nerve stimulation, and cholinesterase inhibition is used to evaluate the therapeutic potential of selective α7 nAChR agonists in these inflammation-related disorders.
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Affiliation(s)
- Hans O Kalkman
- Neuroscience Research, NIBR, Fabrikstrasse 22-3.001.02, 4002, Basel, Switzerland.
- , Gänsbühlgartenweg 7, 4132, Muttenz, Switzerland.
| | - Dominik Feuerbach
- Neuroscience Research, NIBR, Fabrikstrasse 22-3.001.02, 4002, Basel, Switzerland
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47
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Ovsepian SV, O'Leary VB, Zaborszky L. Cholinergic Mechanisms in the Cerebral Cortex: Beyond Synaptic Transmission. Neuroscientist 2016; 22:238-51. [PMID: 26002948 PMCID: PMC4681696 DOI: 10.1177/1073858415588264] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Functional overviews of cholinergic mechanisms in the cerebral cortex have traditionally focused on the release of acetylcholine with modulator and transmitter effects. Recently, however, data have emerged that extend the role of acetylcholine and cholinergic innervations to a range of housekeeping and metabolic functions. These include regulation of amyloid precursor protein (APP) processing with production of amyloid β (Aβ) and other APP fragments and control of the phosphorylation of microtubule-associated protein (MAP) tau. Evidence has been also presented for receptor-ligand like interactions of cholinergic receptors with soluble Aβ peptide and MAP tau, with modulator and signaling effects. Moreover, high-affinity binding of Aβ to the neurotrophin receptor p75 (p75NTR) enriched in basalo-cortical cholinergic projections has been implicated in clearance of Aβ and nucleation of amyloid plaques. Here, we critically evaluate these unorthodox cholinergic mechanisms and discuss their role in neuronal physiology and the biology of Alzheimer's disease.
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Affiliation(s)
- Saak V Ovsepian
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany Faculty of Science and Health, School of Biotechnology, Dublin City University, Dublin, Ireland
| | - Valerie B O'Leary
- Institute of Radiation Biology, Helmholtz Zentrum Munich, Neuherberg, Germany
| | - Laszlo Zaborszky
- Center for Molecular and Behavioral Neuroscience, Rutgers, The State University of New Jersey, Newark, NJ, USA
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48
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Wu J, Liu Q, Tang P, Mikkelsen JD, Shen J, Whiteaker P, Yakel JL. Heteromeric α7β2 Nicotinic Acetylcholine Receptors in the Brain. Trends Pharmacol Sci 2016; 37:562-574. [PMID: 27179601 DOI: 10.1016/j.tips.2016.03.005] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 03/27/2016] [Accepted: 03/30/2016] [Indexed: 10/21/2022]
Abstract
The α7 nicotinic acetylcholine receptor (α7 nAChR) is highly expressed in the brain, where it maintains various neuronal functions including (but not limited to) learning and memory. In addition, the protein expression levels of α7 nAChRs are altered in various brain disorders. The classic rule governing α7 nAChR assembly in the mammalian brain was that it was assembled from five α7 subunits to form a homomeric receptor pentamer. However, emerging evidence demonstrates the presence of heteromeric α7 nAChRs in heterologously expressed systems and naturally in brain neurons, where α7 subunits are co-assembled with β2 subunits to form a novel type of α7β2 nAChR. Interestingly, the α7β2 nAChR exhibits distinctive function and pharmacology from traditional homomeric α7 nAChRs. We review recent advances in probing the distribution, function, pharmacology, pathophysiology, and stoichiometry of the heteromeric α7β2 nAChR, which have provided new insights into the understanding of a novel target of cholinergic signaling.
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Affiliation(s)
- Jie Wu
- Department of Physiology, Shantou University Medicine College, Shantou, Guangdong, China; Divisions of Neurology and Neurobiology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ 85013-4496, USA.
| | - Qiang Liu
- Divisions of Neurology and Neurobiology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ 85013-4496, USA
| | - Pei Tang
- Department of Anesthesiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15260, USA
| | - Jens D Mikkelsen
- Neurobiology Research Unit, University Hospital Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Jianxin Shen
- Department of Physiology, Shantou University Medicine College, Shantou, Guangdong, China
| | - Paul Whiteaker
- Divisions of Neurology and Neurobiology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ 85013-4496, USA
| | - Jerrel L Yakel
- Neurobiology Laboratory, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH)/DHHS, Research Triangle Park, North Carolina 27709, USA
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Corradi J, Bouzat C. Understanding the Bases of Function and Modulation of α7 Nicotinic Receptors: Implications for Drug Discovery. Mol Pharmacol 2016; 90:288-99. [PMID: 27190210 DOI: 10.1124/mol.116.104240] [Citation(s) in RCA: 131] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 05/05/2016] [Indexed: 01/01/2023] Open
Abstract
The nicotinic acetylcholine receptor (nAChR) belongs to a superfamily of pentameric ligand-gated ion channels involved in many physiologic and pathologic processes. Among nAChRs, receptors comprising the α7 subunit are unique because of their high Ca(2+) permeability and fast desensitization. nAChR agonists elicit a transient ion flux response that is further sustained by the release of calcium from intracellular sources. Owing to the dual ionotropic/metabotropic nature of α7 receptors, signaling pathways are activated. The α7 subunit is highly expressed in the nervous system, mostly in regions implicated in cognition and memory and has therefore attracted attention as a novel drug target. Additionally, its dysfunction is associated with several neuropsychiatric and neurologic disorders, such as schizophrenia and Alzheimer's disease. α7 is also expressed in non-neuronal cells, particularly immune cells, where it plays a role in immunity, inflammation, and neuroprotection. Thus, α7 potentiation has emerged as a therapeutic strategy for several neurologic and inflammatory disorders. With unique activation properties, the receptor is a sensitive drug target carrying different potential binding sites for chemical modulators, particularly agonists and positive allosteric modulators. Although macroscopic and single-channel recordings have provided significant information about the underlying molecular mechanisms and binding sites of modulatory compounds, we know just the tip of the iceberg. Further concerted efforts are necessary to effectively exploit α7 as a drug target for each pathologic situation. In this article, we focus mainly on the molecular basis of activation and drug modulation of α7, key pillars for rational drug design.
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Affiliation(s)
- Jeremías Corradi
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Universidad Nacional del Sur, CONICET/UNS, Bahía Blanca, Argentina
| | - Cecilia Bouzat
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Universidad Nacional del Sur, CONICET/UNS, Bahía Blanca, Argentina
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Phosphoinositides: Two-Path Signaling in Neuronal Response to Oligomeric Amyloid β Peptide. Mol Neurobiol 2016; 54:3236-3252. [DOI: 10.1007/s12035-016-9885-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/28/2016] [Indexed: 12/12/2022]
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