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Sarkar S, Martinez Reyes C, Jensen CM, Gavornik JP. M2 receptors are required for spatiotemporal sequence learning in mouse primary visual cortex. J Neurophysiol 2024; 131:1213-1225. [PMID: 38629848 DOI: 10.1152/jn.00016.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 03/08/2024] [Accepted: 04/16/2024] [Indexed: 06/09/2024] Open
Abstract
Acetylcholine is a neurotransmitter that plays a variety of roles in the central nervous system. It was previously shown that blocking muscarinic receptors with a nonselective antagonist prevents a form of experience-dependent plasticity termed "spatiotemporal sequence learning" in the mouse primary visual cortex (V1). Muscarinic signaling is a complex process involving the combined activities of five different G protein-coupled receptors, M1-M5, all of which are expressed in the murine brain but differ from each other functionally and in anatomical localization. Here we present electrophysiological evidence that M2, but not M1, receptors are required for spatiotemporal sequence learning in mouse V1. We show in male mice that M2 is highly expressed in the neuropil in V1, especially in thalamorecipient layer 4, and colocalizes with the soma in a subset of somatostatin-expressing neurons in deep layers. We also show that expression of M2 receptors is higher in the monocular region of V1 than it is in the binocular region but that the amount of experience-dependent sequence potentiation is similar in both regions and that blocking muscarinic signaling after visual stimulation does not prevent plasticity. This work establishes a new functional role for M2-type receptors in processing temporal information and demonstrates that monocular circuits are modified by experience in a manner similar to binocular circuits.NEW & NOTEWORTHY Muscarinic acetylcholine receptors are required for multiple forms of plasticity in the brain and support perceptual functions, but the precise role of the five subtypes (M1-M5) are unclear. Here we show that the M2 receptor is specifically required to encode experience-dependent representations of spatiotemporal relationships in both monocular and binocular regions of mouse V1. This work identifies a novel functional role for M2 receptors in coding temporal information into cortical circuits.
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Affiliation(s)
- Susrita Sarkar
- Center for Systems Neuroscience, Department of Biology, Boston University, Boston, Massachusetts, United States
| | - Catalina Martinez Reyes
- Center for Systems Neuroscience, Department of Biology, Boston University, Boston, Massachusetts, United States
| | - Cambria M Jensen
- Center for Systems Neuroscience, Department of Biology, Boston University, Boston, Massachusetts, United States
| | - Jeffrey P Gavornik
- Center for Systems Neuroscience, Department of Biology, Boston University, Boston, Massachusetts, United States
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Cadeddu R, Braccagni G, Branca C, van Luik ER, Pittenger C, Thomsen MS, Bortolato M. Activation of M 4 muscarinic receptors in the striatum reduces tic-like behaviours in two distinct murine models of Tourette syndrome. Br J Pharmacol 2024. [PMID: 38689378 DOI: 10.1111/bph.16392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 03/15/2024] [Accepted: 03/18/2024] [Indexed: 05/02/2024] Open
Abstract
BACKGROUND AND PURPOSE Current pharmacotherapies for Tourette syndrome (TS) are often unsatisfactory and poorly tolerated, underscoring the need for novel treatments. Insufficient striatal acetylcholine has been suggested to contribute to tic ontogeny. Thus, we tested whether activating M1 and/or M4 receptors-the two most abundant muscarinic receptors in the striatum-reduced tic-related behaviours in mouse models of TS. EXPERIMENTAL APPROACH Studies were conducted using CIN-d and D1CT-7 mice, two TS models characterized by early-life depletion of striatal cholinergic interneurons and cortical neuropotentiation, respectively. First, we tested the effects of systemic and intrastriatal xanomeline, a selective M1/M4 receptor agonist, on tic-like and other TS-related responses. Then, we examined whether xanomeline effects were reduced by either M1 or M4 antagonists or mimicked by the M1/M3 agonist cevimeline or the M4 positive allosteric modulator (PAM) VU0467154. Finally, we measured striatal levels of M1 and M4 receptors and assessed the impact of VU0461754 on the striatal expression of the neural marker activity c-Fos. KEY RESULTS Systemic and intrastriatal xanomeline reduced TS-related behaviours in CIN-d and D1CT-7 mice. Most effects were blocked by M4, but not M1, receptor antagonists. VU0467154, but not cevimeline, elicited xanomeline-like ameliorative effects in both models. M4, but not M1, receptors were down-regulated in the striatum of CIN-d mice. Additionally, VU0467154 reduced striatal c-Fos levels in these animals. CONCLUSION AND IMPLICATIONS Activation of striatal M4, but not M1, receptors reduced tic-like manifestations in mouse models, pointing to xanomeline and M4 PAMs as novel putative therapeutic strategies for TS.
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Affiliation(s)
- Roberto Cadeddu
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, Utah, USA
| | - Giulia Braccagni
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, Utah, USA
| | - Caterina Branca
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, Utah, USA
| | - Easton R van Luik
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, Utah, USA
| | - Christopher Pittenger
- Department of Psychiatry, School of Medicine, Yale University, New Haven, Connecticut, USA
- Department of Psychology, School of Arts and Sciences, Yale University, New Haven, Connecticut, USA
- Child Study Center, School of Medicine, Yale University, New Haven, Connecticut, USA
- Center for Brain and Mind Health, School of Medicine, Yale University, New Haven, Connecticut, USA
| | | | - Marco Bortolato
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, Utah, USA
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Hayashi R, Srisomboon Y, Iijima K, Maniak PJ, Tei R, Kobayashi T, Matsunaga M, Luo H, Masuda MY, O'Grady SM, Kita H. Cholinergic sensing of allergen exposure by airway epithelium promotes type 2 immunity in the lungs. J Allergy Clin Immunol 2024; 153:793-808.e2. [PMID: 38000698 PMCID: PMC10939907 DOI: 10.1016/j.jaci.2023.10.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 09/26/2023] [Accepted: 10/09/2023] [Indexed: 11/26/2023]
Abstract
BACKGROUND Nonneuronal cells, including epithelial cells, can produce acetylcholine (ACh). Muscarinic ACh receptor antagonists are used clinically to treat asthma and other medical conditions; however, knowledge regarding the roles of ACh in type 2 immunity is limited. OBJECTIVE Our aim was to investigate the roles of epithelial ACh in allergic immune responses. METHODS Human bronchial epithelial (HBE) cells were cultured with allergen extracts, and their ACh production and IL-33 secretion were studied in vitro. To investigate immune responses in vivo, naive BALB/c mice were treated intranasally with different muscarinic ACh receptor antagonists and then exposed intranasally to allergens. RESULTS At steady state, HBE cells expressed cellular components necessary for ACh production, including choline acetyltransferase and organic cation transporters. Exposure to allergens caused HBE cells to rapidly release ACh into the extracellular medium. Pharmacologic or small-interfering RNA-based blocking of ACh production or autocrine action through the M3 muscarinic ACh receptors in HBE cells suppressed allergen-induced ATP release, calcium mobilization, and extracellular secretion of IL-33. When naive mice were exposed to allergens, ACh was quickly released into the airway lumen. A series of clinical M3 muscarinic ACh receptor antagonists inhibited allergen-induced IL-33 secretion and innate type 2 immune response in the mouse airways. In a preclinical murine model of asthma, an ACh receptor antagonist suppressed allergen-induced airway inflammation and airway hyperreactivity. CONCLUSIONS ACh is released quickly by airway epithelial cells on allergen exposure, and it plays an important role in type 2 immunity. The epithelial ACh system can be considered a therapeutic target in allergic airway diseases.
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Affiliation(s)
- Ryusuke Hayashi
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz
| | - Yotesawee Srisomboon
- Department of Animal Science, University of Minnesota, St Paul, Minn; Department of Integrative Biology and Physiology, University of Minnesota, St Paul, Minn
| | - Koji Iijima
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz
| | - Peter J Maniak
- Department of Animal Science, University of Minnesota, St Paul, Minn; Department of Integrative Biology and Physiology, University of Minnesota, St Paul, Minn
| | - Rinna Tei
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz
| | - Takao Kobayashi
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz
| | - Mayumi Matsunaga
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz
| | - Huijun Luo
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz
| | - Mia Y Masuda
- Mayo Clinic Graduate School of Biomedical Sciences, Rochester, Minn; Mayo Clinic Graduate School of Biomedical Sciences, Scottsdale, Ariz
| | - Scott M O'Grady
- Department of Animal Science, University of Minnesota, St Paul, Minn; Department of Integrative Biology and Physiology, University of Minnesota, St Paul, Minn
| | - Hirohito Kita
- Division of Allergy, Asthma and Clinical Immunology, Mayo Clinic, Scottsdale, Ariz; Department of Medicine, Mayo Clinic, Scottsdale, Ariz; Department of Immunology, Mayo Clinic Rochester, Rochester, Minn; Department of Immunology, Mayo Clinic Arizona, Scottsdale, Ariz.
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Aroniadou-Anderjaska V, Figueiredo TH, de Araujo Furtado M, Pidoplichko VI, Braga MFM. Mechanisms of Organophosphate Toxicity and the Role of Acetylcholinesterase Inhibition. TOXICS 2023; 11:866. [PMID: 37888716 PMCID: PMC10611379 DOI: 10.3390/toxics11100866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/11/2023] [Accepted: 10/17/2023] [Indexed: 10/28/2023]
Abstract
Organophosphorus compounds (OPs) have applications in agriculture (e.g., pesticides), industry (e.g., flame retardants), and chemical warfare (nerve agents). In high doses or chronic exposure, they can be toxic or lethal. The primary mechanism, common among all OPs, that initiates their toxic effects is the inhibition of acetylcholinesterase. In acute OP exposure, the subsequent surge of acetylcholine in cholinergic synapses causes a peripheral cholinergic crisis and status epilepticus (SE), either of which can lead to death. If death is averted without effective seizure control, long-term brain damage ensues. This review describes the mechanisms by which elevated acetylcholine can cause respiratory failure and trigger SE; the role of the amygdala in seizure initiation; the role of M1 muscarinic receptors in the early stages of SE; the neurotoxic pathways activated by SE (excitotoxicity/Ca++ overload/oxidative stress, neuroinflammation); and neurotoxic mechanisms linked to low-dose, chronic exposure (Ca++ dyshomeostasis/oxidative stress, inflammation), which do not depend on SE and do not necessarily involve acetylcholinesterase inhibition. The evidence so far indicates that brain damage from acute OP exposure is a direct result of SE, while the neurotoxic mechanisms activated by low-dose chronic exposure are independent of SE and may not be associated with acetylcholinesterase inhibition.
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Affiliation(s)
- Vassiliki Aroniadou-Anderjaska
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (V.A.-A.); (V.I.P.)
- Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Taiza H. Figueiredo
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (V.A.-A.); (V.I.P.)
| | - Marcio de Araujo Furtado
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (V.A.-A.); (V.I.P.)
| | - Volodymyr I. Pidoplichko
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (V.A.-A.); (V.I.P.)
| | - Maria F. M. Braga
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA; (V.A.-A.); (V.I.P.)
- Department of Psychiatry, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
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Sundel MH, Sampaio Moura N, Cheng K, Chatain O, Hu S, Drachenberg CB, Xie G, Raufman JP. Selective Activation of M 1 Muscarinic Receptors Attenuates Human Colon Cancer Cell Proliferation. Cancers (Basel) 2023; 15:4766. [PMID: 37835460 PMCID: PMC10571583 DOI: 10.3390/cancers15194766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 09/20/2023] [Accepted: 09/22/2023] [Indexed: 10/15/2023] Open
Abstract
M3 muscarinic receptor (M3R) activation stimulates colon cancer cell proliferation, migration, and invasion; M3R expression is augmented in colon cancer and ablating M3R expression in mice attenuates colon neoplasia. Several lines of investigation suggest that in contrast to these pro-neoplastic effects of M3R, M1R plays an opposite role, protecting colon epithelial cells against neoplastic transformation. To pursue these intriguing findings, we examined the relative expression of M1R versus M3R in progressive stages of colon neoplasia and the effect of treating colon cancer cells with selective M1R agonists. We detected divergent expression of M1R and M3R in progressive colon neoplasia, from aberrant crypt foci to adenomas, primary colon cancers, and colon cancer metastases. Treating three human colon cancer cell lines with two selective M1R agonists, we found that in contrast to the effects of M3R activation, selective activation of M1R reversibly inhibited cell proliferation. Moreover, these effects were diminished by pre-incubating cells with a selective M1R inhibitor. Mechanistic insights were gained using selective chemical inhibitors of post-muscarinic receptor signaling molecules and immunoblotting to demonstrate M1R-dependent changes in the activation (phosphorylation) of key downstream kinases, EGFR, ERK1/2, and p38 MAPK. We did not detect a role for drug toxicity, cellular senescence, or apoptosis in mediating M1R agonist-induced attenuated cell proliferation. Lastly, adding M1R-selective agonists to colon cancer cells augmented the anti-proliferative effects of conventional chemotherapeutic agents. Collectively, these results suggest that selective M1R agonism for advanced colon cancer, alone or in combination with conventional chemotherapy, is a therapeutic strategy worth exploring.
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Affiliation(s)
- Margaret H. Sundel
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA;
| | - Natalia Sampaio Moura
- Department of Medicine, Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (N.S.M.); (K.C.); (O.C.); (S.H.); (G.X.)
| | - Kunrong Cheng
- Department of Medicine, Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (N.S.M.); (K.C.); (O.C.); (S.H.); (G.X.)
| | - Oscar Chatain
- Department of Medicine, Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (N.S.M.); (K.C.); (O.C.); (S.H.); (G.X.)
| | - Shien Hu
- Department of Medicine, Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (N.S.M.); (K.C.); (O.C.); (S.H.); (G.X.)
| | - Cinthia B. Drachenberg
- Department of Pathology, University of Maryland School of Medicine, Baltimore, MD 21201, USA;
| | - Guofeng Xie
- Department of Medicine, Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (N.S.M.); (K.C.); (O.C.); (S.H.); (G.X.)
- VA Maryland Healthcare System, Baltimore, MD 21201, USA
- Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Jean-Pierre Raufman
- Department of Medicine, Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (N.S.M.); (K.C.); (O.C.); (S.H.); (G.X.)
- VA Maryland Healthcare System, Baltimore, MD 21201, USA
- Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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Sinha AK, Lee C, Holt JC. Elucidating the role of muscarinic acetylcholine receptor (mAChR) signaling in efferent mediated responses of vestibular afferents in mammals. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.31.549902. [PMID: 37577578 PMCID: PMC10418111 DOI: 10.1101/2023.07.31.549902] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
The peripheral vestibular system detects head position and movement through activation of vestibular hair cells (HCs) in vestibular end organs. HCs transmit this information to the CNS by way of primary vestibular afferent neurons. The CNS, in turn, modulates HCs and afferents via the efferent vestibular system (EVS) through activation of cholinergic signaling mechanisms. In mice, we previously demonstrated that activation of muscarinic acetylcholine receptors (mAChRs), during EVS stimulation, gives rise to a slow excitation that takes seconds to peak and tens of seconds to decay back to baseline. This slow excitation is mimicked by muscarine and ablated by the non-selective mAChR blockers scopolamine, atropine, and glycopyrrolate. While five distinct mAChRs (M1-M5) exist, the subtype(s) driving EVS-mediated slow excitation remain unidentified and details on how these mAChRs alter vestibular function is not well understood. The objective of this study is to characterize which mAChR subtypes drive the EVS-mediated slow excitation, and how their activation impacts vestibular physiology and behavior. In C57Bl/6J mice, M3mAChR antagonists were more potent at blocking slow excitation than M1mAChR antagonists, while M2/M4 blockers were ineffective. While unchanged in M2/M4mAChR double KO mice, EVS-mediated slow excitation in M3 mAChR-KO animals were reduced or absent in irregular afferents but appeared unchanged in regular afferents. In agreement, vestibular sensory-evoked potentials (VsEP), known to be predominantly generated from irregular afferents, were significantly less enhanced by mAChR activation in M3mAChR-KO mice compared to controls. Finally, M3mAChR-KO mice display distinct behavioral phenotypes in open field activity, and thermal profiles, and balance beam and forced swim test. M3mAChRs mediate efferent-mediated slow excitation in irregular afferents, while M1mAChRs may drive the same process in regular afferents.
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Nakajima Y, Tsujimura T, Tsutsui Y, Chotirungsan T, Kawada S, Dewa N, Magara J, Inoue M. Atropine facilitates water-evoked swallows via central muscarinic receptors in anesthetized rats. Am J Physiol Gastrointest Liver Physiol 2023; 325:G109-G121. [PMID: 37219016 DOI: 10.1152/ajpgi.00039.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 05/01/2023] [Accepted: 05/16/2023] [Indexed: 05/24/2023]
Abstract
Anticholinergic medication causes impaired swallowing with hyposalivation. However, the underlying mechanisms by which these drugs modulate the swallowing reflex remain unclear. This study investigated the effects of the muscarinic acetylcholine receptor (mAChR) nonspecific antagonist atropine on the initiation of swallowing. Experiments were performed on 124 urethane-anesthetized rats. A swallow was evoked by either topical laryngeal application of a small amount of distilled water (DW), saline, citric acid, or capsaicin; upper airway distention with a continuous airflow; electrical stimulation of the superior laryngeal nerve (SLN); or focal microinjection of N-methyl-d-aspartate (NMDA) into the lateral region of the nucleus of the solitary tract (L-nTS). Swallows were identified by electromyographic bursts of the digastric and thyrohyoid muscles. Either atropine, the peripheral mAChR antagonist methylatropine, or antagonists of mAChR subtypes M1-M5 were intravenously delivered. Atropine at a dose of 1 mg/kg increased the number of DW-evoked swallows compared with baseline and did not affect the number of swallows evoked by saline, citric acid, capsaicin, or upper airway distention. Methylatropine and M1-M5 antagonists did not significantly change the number of DW-evoked swallows. Bilateral SLN transection completely abolished DW-evoked swallows, and atropine decreased the swallowing threshold of SLN electrical stimulation. Finally, microinjection of NMDA receptor antagonist AP-5 into the L-nTS inhibited DW-evoked swallows, and atropine facilitated the initiation of swallowing evoked by NMDA microinjection into this region. These results suggest that atropine facilitates DW-evoked swallows via central mAChR actions.NEW & NOTEWORTHY Atropine facilitated the distilled water (DW)-evoked swallows in anesthetized rats. Atropine decreased the swallowing threshold evoked by electrical stimulation of the superior laryngeal nerve, which is a primary sensory nerve for the initiation of DW-evoked swallows. Atropine facilitated the swallows evoked by N-methyl-d-aspartate microinjection into the lateral region of the nucleus of the solitary tract, which is involved in the DW-evoked swallows. We speculate that atropine facilitates the DW-evoked swallows via central muscarinic receptor actions.
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Affiliation(s)
- Yuta Nakajima
- Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Takanori Tsujimura
- Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Yuhei Tsutsui
- Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Titi Chotirungsan
- Department of Oral Diagnosis, Faculty of Dentistry, Naresuan University, Muang, Phitsanulok, Thailand
| | - Satomi Kawada
- Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Nozomi Dewa
- Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Jin Magara
- Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Makoto Inoue
- Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
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Differential Regulation of Prelimbic and Thalamic Transmission to the Basolateral Amygdala by Acetylcholine Receptors. J Neurosci 2023; 43:722-735. [PMID: 36535767 PMCID: PMC9899087 DOI: 10.1523/jneurosci.2545-21.2022] [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: 12/28/2021] [Revised: 12/12/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022] Open
Abstract
The amygdalar anterior basolateral nucleus (BLa) plays a vital role in emotional behaviors. This region receives dense cholinergic projections from basal forebrain which are critical in regulating neuronal activity in BLa. Cholinergic signaling in BLa has also been shown to modulate afferent glutamatergic inputs to this region. However, these studies, which have used cholinergic agonists or prolonged optogenetic stimulation of cholinergic fibers, may not reflect the effect of physiological acetylcholine release in the BLa. To better understand these effects of acetylcholine, we have used electrophysiology and optogenetics in male and female mouse brain slices to examine cholinergic regulation of afferent BLa input from cortex and midline thalamic nuclei. Phasic ACh release evoked by single pulse stimulation of cholinergic terminals had a biphasic effect on transmission at cortical input, producing rapid nicotinic receptor-mediated facilitation followed by slower mAChR-mediated depression. In contrast, at this same input, sustained ACh elevation through application of the cholinesterase inhibitor physostigmine suppressed glutamatergic transmission through mAChRs only. This suppression was not observed at midline thalamic nuclei inputs to BLa. In agreement with this pathway specificity, the mAChR agonist, muscarine more potently suppressed transmission at inputs from prelimbic cortex than thalamus. Muscarinic inhibition at prelimbic cortex input required presynaptic M4 mAChRs, while at thalamic input it depended on M3 mAChR-mediated stimulation of retrograde endocannabinoid signaling. Muscarinic inhibition at both pathways was frequency-dependent, allowing only high-frequency activity to pass. These findings demonstrate complex cholinergic regulation of afferent input to BLa that is pathway-specific and frequency-dependent.SIGNIFICANCE STATEMENT Cholinergic modulation of the basolateral amygdala regulates formation of emotional memories, but the underlying mechanisms are not well understood. Here, we show, using mouse brain slices, that ACh differentially regulates afferent transmission to the BLa from cortex and midline thalamic nuclei. Fast, phasic ACh release from a single optical stimulation biphasically regulates glutamatergic transmission at cortical inputs through nicotinic and muscarinic receptors, suggesting that cholinergic neuromodulation can serve precise, computational roles in the BLa. In contrast, sustained ACh elevation regulates cortical input through muscarinic receptors only. This muscarinic regulation is pathway-specific with cortical input inhibited more strongly than midline thalamic nuclei input. Specific targeting of these cholinergic receptors may thus provide a therapeutic strategy to bias amygdalar processing and regulate emotional memory.
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Li WP, Su XH, Hu NY, Hu J, Li XW, Yang JM, Gao TM. Astrocytes Mediate Cholinergic Regulation of Adult Hippocampal Neurogenesis and Memory Through M 1 Muscarinic Receptor. Biol Psychiatry 2022; 92:984-998. [PMID: 35787318 DOI: 10.1016/j.biopsych.2022.04.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 04/02/2022] [Accepted: 04/27/2022] [Indexed: 11/02/2022]
Abstract
BACKGROUND In the neurogenic niches of the adult hippocampus, new functional neurons are continuously generated throughout life, and generation of these neurons has been implicated in learning and memory. Astrocytes, as components of the neurogenic niches, are critical in the regulation of adult hippocampal neurogenesis (AHN). However, little is known about how astrocytes receive and respond to extrinsic cues to regulate AHN. METHODS By using a transgenic strategy to conditionally delete astrocytic CRHM1 in mice and AAV (adeno-associated virus)-mediated overexpression of astrocytic CHRM1 specifically in the hippocampal dentate gyrus, we systematically investigated the role of astrocytic CHRM1 in the regulation of AHN and the underlying mechanisms using the combined approaches of immunohistochemistry, retrovirus labeling, electrophysiology, primary astrocyte cultures, immunoblotting, and behavioral assays. RESULTS We report that genetic ablation of CHRM1 in astrocytes led to defects in neural stem cell survival, neuronal differentiation, and maturation and integration of newborn neurons in the dentate gyrus. Astrocytic CHRM1-mediated modulation of AHN was mediated by BDNF (brain-derived neurotrophic factor) signaling. Furthermore, CHRM1 ablation in astrocytes impaired contextual fear memory. These impairments in both AHN and memory were rescued by overexpression of astrocytic CHRM1 in the dentate gyrus. CONCLUSIONS Our findings reveal a critical role for astrocytes in mediating cholinergic regulation of AHN and memory through CHRM1.
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Affiliation(s)
- Wei-Peng Li
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China; Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Xiao-Hong Su
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China; Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Neng-Yuan Hu
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China; Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Jian Hu
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China; Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Xiao-Wen Li
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Jian-Ming Yang
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China.
| | - Tian-Ming Gao
- State Key Laboratory of Organ Failure Research, Institutes of Brain Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China; Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangdong Province Key Laboratory of Psychiatric Disorders, Department of Neurobiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China.
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10
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Myslivecek J. Multitargeting nature of muscarinic orthosteric agonists and antagonists. Front Physiol 2022; 13:974160. [PMID: 36148314 PMCID: PMC9486310 DOI: 10.3389/fphys.2022.974160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/01/2022] [Indexed: 11/16/2022] Open
Abstract
Muscarinic receptors (mAChRs) are typical members of the G protein-coupled receptor (GPCR) family and exist in five subtypes from M1 to M5. Muscarinic receptor subtypes do not sufficiently differ in affinity to orthosteric antagonists or agonists; therefore, the analysis of receptor subtypes is complicated, and misinterpretations can occur. Usually, when researchers mainly specialized in CNS and peripheral functions aim to study mAChR involvement in behavior, learning, spinal locomotor networks, biological rhythms, cardiovascular physiology, bronchoconstriction, gastrointestinal tract functions, schizophrenia, and Parkinson’s disease, they use orthosteric ligands and they do not use allosteric ligands. Moreover, they usually rely on manufacturers’ claims that could be misleading. This review aimed to call the attention of researchers not deeply focused on mAChR pharmacology to this fact. Importantly, limited selective binding is not only a property of mAChRs but is a general attribute of most neurotransmitter receptors. In this review, we want to give an overview of the most common off-targets for established mAChR ligands. In this context, an important point is a mention the tremendous knowledge gap on off-targets for novel compounds compared to very well-established ligands. Therefore, we will summarize reported affinities and give an outline of strategies to investigate the subtype’s function, thereby avoiding ambiguous results. Despite that, the multitargeting nature of drugs acting also on mAChR could be an advantage when treating such diseases as schizophrenia. Antipsychotics are a perfect example of a multitargeting advantage in treatment. A promising strategy is the use of allosteric ligands, although some of these ligands have also been shown to exhibit limited selectivity. Another new direction in the development of muscarinic selective ligands is functionally selective and biased agonists. The possible selective ligands, usually allosteric, will also be listed. To overcome the limited selectivity of orthosteric ligands, the recommended process is to carefully examine the presence of respective subtypes in specific tissues via knockout studies, carefully apply “specific” agonists/antagonists at appropriate concentrations and then calculate the probability of a specific subtype involvement in specific functions. This could help interested researchers aiming to study the central nervous system functions mediated by the muscarinic receptor.
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11
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Phosphoproteomic of the acetylcholine pathway enables discovery of the PKC-β-PIX-Rac1-PAK cascade as a stimulatory signal for aversive learning. Mol Psychiatry 2022; 27:3479-3492. [PMID: 35665767 PMCID: PMC9708603 DOI: 10.1038/s41380-022-01643-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 05/13/2022] [Accepted: 05/23/2022] [Indexed: 11/08/2022]
Abstract
Acetylcholine is a neuromodulator critical for learning and memory. The cholinesterase inhibitor donepezil increases brain acetylcholine levels and improves Alzheimer's disease (AD)-associated learning disabilities. Acetylcholine activates striatal/nucleus accumbens dopamine receptor D2-expressing medium spiny neurons (D2R-MSNs), which regulate aversive learning through muscarinic receptor M1 (M1R). However, how acetylcholine stimulates learning beyond M1Rs remains unresolved. Here, we found that acetylcholine stimulated protein kinase C (PKC) in mouse striatal/nucleus accumbens. Our original kinase-oriented phosphoproteomic analysis revealed 116 PKC substrate candidates, including Rac1 activator β-PIX. Acetylcholine induced β-PIX phosphorylation and activation, thereby stimulating Rac1 effector p21-activated kinase (PAK). Aversive stimulus activated the M1R-PKC-PAK pathway in mouse D2R-MSNs. D2R-MSN-specific expression of PAK mutants by the Cre-Flex system regulated dendritic spine structural plasticity and aversive learning. Donepezil induced PAK activation in both accumbal D2R-MSNs and in the CA1 region of the hippocampus and enhanced D2R-MSN-mediated aversive learning. These findings demonstrate that acetylcholine stimulates M1R-PKC-β-PIX-Rac1-PAK signaling in D2R-MSNs for aversive learning and imply the cascade's therapeutic potential for AD as aversive learning is used to preliminarily screen AD drugs.
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12
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7,8-Dihydroxyflavone Enhanced Colonic Cholinergic Contraction and Relieved Loperamide-Induced Constipation in Rats. Dig Dis Sci 2021; 66:4251-4262. [PMID: 33528684 DOI: 10.1007/s10620-020-06817-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 12/29/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND Whether 7,8-dihydroxyflavone (7,8-DHF), a tyrosine kinase receptor B (TrkB) agonist, modulates colonic smooth muscle motility and/or alleviates constipation has not yet been studied. AIMS Here, we aimed to determine how 7,8-DHF influences carbachol (CCh)-stimulated contraction of colonic strips and the in vivo effect of 7,8-DHF on constipation. METHODS Muscle strips were isolated from rat colons for recording contractile tension and performing western blotting. Constipation was induced in rats with loperamide. RESULTS Although it specifically activated TrkB, 7,8-DHF applied alone neither activated PLCγ1 in the colonic strips nor induced colonic strip contraction. However, 7,8-DHF enhanced CCh-stimulated PLCγ1 activation and strip contraction. The PLCγ1 antagonist U73122 suppressed both CCh-stimulated and 7,8-DHF-enhanced/CCh-stimulated contraction. While clarifying the underlying mechanism, we revealed that 7,8-DHF augmented muscarinic M3 receptor expression in the colonic strips. The M3-selective antagonist tarafenacin specifically inhibited the 7,8-DHF-enhanced/CCh-stimulated contraction of the colonic strips. Since 7,8-DHF increased Akt phosphorylation, and LY294002 (an antagonist of PI3K upstream of Akt) dramatically inhibited both 7,8-DHF-augmented M3 expression and 7,8-DHF-enhanced/CCh-stimulated contractions, we assumed that 7,8-DHF/TrkB/Akt was associated with the modulation of M3 expression in the colonic strips. ANA-12, a specific TrkB antagonist, not only inhibited TrkB activation by 7,8-DHF but also suppressed 7,8-DHF-enhanced cholinergic contraction, 7,8-DHF/CCh-mediated activation of PLCγ1/Akt, and M3 overexpression in colonic strips. In vivo 7,8-DHF, also by promoting intestinal motility and M3 expression, significantly alleviated loperamide-induced functional constipation in rats. CONCLUSIONS Our results suggest that 7,8-DHF regulates colonic motility possibly via a TrkB/Akt/M3 pathway and may be applicable for alleviating constipation.
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Crittenden JR, Zhai S, Sauvage M, Kitsukawa T, Burguière E, Thomsen M, Zhang H, Costa C, Martella G, Ghiglieri V, Picconi B, Pescatore KA, Unterwald EM, Jackson WS, Housman DE, Caine SB, Sulzer D, Calabresi P, Smith AC, Surmeier DJ, Graybiel AM. CalDAG-GEFI mediates striatal cholinergic modulation of dendritic excitability, synaptic plasticity and psychomotor behaviors. Neurobiol Dis 2021; 158:105473. [PMID: 34371144 PMCID: PMC8486000 DOI: 10.1016/j.nbd.2021.105473] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 07/21/2021] [Accepted: 08/02/2021] [Indexed: 01/19/2023] Open
Abstract
CalDAG-GEFI (CDGI) is a protein highly enriched in the striatum, particularly in the principal spiny projection neurons (SPNs). CDGI is strongly down-regulated in two hyperkinetic conditions related to striatal dysfunction: Huntington’s disease and levodopa-induced dyskinesia in Parkinson’s disease. We demonstrate that genetic deletion of CDGI in mice disrupts dendritic, but not somatic, M1 muscarinic receptors (M1Rs) signaling in indirect pathway SPNs. Loss of CDGI reduced temporal integration of excitatory postsynaptic potentials at dendritic glutamatergic synapses and impaired the induction of activity-dependent long-term potentiation. CDGI deletion selectively increased psychostimulant-induced repetitive behaviors, disrupted sequence learning, and eliminated M1R blockade of cocaine self-administration. These findings place CDGI as a major, but previously unrecognized, mediator of cholinergic signaling in the striatum. The effects of CDGI deletion on the self-administration of drugs of abuse and its marked alterations in hyperkinetic extrapyramidal disorders highlight CDGI’s therapeutic potential.
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Affiliation(s)
- Jill R Crittenden
- McGovern Institute for Brain Research and Dept. of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Koch Institute for Integrative Cancer Research, MIT, Cambridge, MA 02139, USA
| | - Shenyu Zhai
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Magdalena Sauvage
- McGovern Institute for Brain Research and Dept. of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Leibniz Institute for Neurobiology, Functional Architecture of Memory Dept., Magdeburg, Germany
| | - Takashi Kitsukawa
- Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
| | - Eric Burguière
- McGovern Institute for Brain Research and Dept. of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Brain and Spine Institute (ICM), CNRS UMR 7225, INSERM U 1127, UPMC-P6 UMR S, 1127, Hôpital de la Pitié-Salpêtrière, 47 boulevard de l'hôpital, Paris, France
| | - Morgane Thomsen
- Laboratory of Neuropsychiatry, Psychiatric Centre Copenhagen and University, DK-2100, Copenhagen, Denmark; Basic Neuroscience Division, McLean Hospital/Harvard Medical School, Belmont, MA 02478, USA
| | - Hui Zhang
- Departments of Psychiatry, Pharmacology, Neurology, Columbia University, New York State Psychiatric Institute, New York, NY 10032, USA; Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Cinzia Costa
- Neurological Clinic, Department of Medicine, Hospital Santa Maria della misericordia, University of Perugia, 06100 Perugia, Italy
| | - Giuseppina Martella
- Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 64, 00143 Rome, Italy
| | | | | | - Karen A Pescatore
- Department of Pharmacology and Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, PA 19140, USA
| | - Ellen M Unterwald
- Department of Pharmacology and Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, PA 19140, USA
| | - Walker S Jackson
- Wallenberg Center for Molecular Medicine, Department of Clinical and Experimental Medicine, Linköping University, 581 83 Linköping, Sweden
| | - David E Housman
- Koch Institute for Integrative Cancer Research, MIT, Cambridge, MA 02139, USA
| | - S Barak Caine
- Basic Neuroscience Division, McLean Hospital/Harvard Medical School, Belmont, MA 02478, USA
| | - David Sulzer
- Departments of Psychiatry, Pharmacology, Neurology, Columbia University, New York State Psychiatric Institute, New York, NY 10032, USA
| | - Paolo Calabresi
- Neurological Clinic, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, 00168 Rome, Italy; Department of Neuroscience, Faculty of Medicine, Università Cattolica del "Sacro Cuore", 00168 Rome, Italy
| | - Anne C Smith
- Evelyn F. McKnight Brain Institute, University of Arizona, Tucson, AZ 85724, USA
| | - D James Surmeier
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Ann M Graybiel
- McGovern Institute for Brain Research and Dept. of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA.
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Mohan S, Tiwari MN, Stanojević M, Biala Y, Yaari Y. Muscarinic regulation of the neuronal Na + /K + -ATPase in rat hippocampus. J Physiol 2021; 599:3735-3754. [PMID: 34148230 DOI: 10.1113/jp281460] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 06/16/2021] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Stimulation of postsynaptic muscarinic receptors was shown to excite principal hippocampal neurons by modulating several membrane ion conductances. We show here that activation of postsynaptic muscarinic receptors also causes neuronal excitation by inhibiting Na+ /K+ -ATPase activity. Muscarinic Na+ /K+ -ATPase inhibition is mediated by two separate signalling pathways that lead downstream to enhanced Na+ /K+ -ATPase phosphorylation by activating protein kinase C and protein kinase G. Muscarinic excitation through Na+ /K+ -ATPase inhibition is probably involved in cholinergic modulation of hippocampal activity and may turn out to be a widespread mechanism of neuronal excitation in the brain. ABSTRACT Stimulation of muscarinic cholinergic receptors on principal hippocampal neurons enhances intrinsic neuronal excitability by modulating several membrane ion conductances. The electrogenic Na+ /K+ -ATPase (NKA; the 'Na+ pump') is a ubiquitous regulator of intrinsic neuronal excitability, generating a hyperpolarizing current to thwart excessive neuronal firing. Using electrophysiological and pharmacological methodologies in rat hippocampal slices, we show that neuronal NKA pumping activity is also subjected to cholinergic regulation. Stimulation of postsynaptic muscarinic, but not nicotinic, cholinergic receptors activates membrane-bound phospholipase C and hydrolysis of membrane-integral phosphatidylinositol 4,5-bisphosphate into diacylglycerol (DAG) and inositol 1,4,5-triphosphate (IP3 ). Along one signalling pathway, DAG activates protein kinase C (PKC). Along a second signalling pathway, IP3 causes Ca2+ release from the endoplasmic reticulum, facilitating nitric oxide (NO) production. The rise in NO levels stimulates cGMP synthesis by guanylate-cyclase, activating protein kinase G (PKG). The two pathways converge to cause partial NKA inhibition through enzyme phosphorylation by PKC and PKG, leading to a marked increase in intrinsic neuronal excitability. This novel mechanism of neuronal NKA regulation probably contributes to the cholinergic modulation of hippocampal activity in spatial navigation, learning and memory.
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Affiliation(s)
- Sandesh Mohan
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah School of Medicine, Jerusalem, 91120, Israel
| | - Manindra Nath Tiwari
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah School of Medicine, Jerusalem, 91120, Israel
| | - Marija Stanojević
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah School of Medicine, Jerusalem, 91120, Israel
| | - Yoav Biala
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah School of Medicine, Jerusalem, 91120, Israel
| | - Yoel Yaari
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah School of Medicine, Jerusalem, 91120, Israel
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Mali SN, Pandey A. 1,2,5-Thiadiazole Scaffold: A review on recent progress in biological activities. Comb Chem High Throughput Screen 2021; 25:771-787. [PMID: 34161208 DOI: 10.2174/1386207324666210622162001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 04/20/2021] [Accepted: 04/30/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Thiadiazoles can be considered as the privileged scaffold having diverse pharmacological potentials such as antihypertensive, anti-HIV, antimicrobials, antileishmanial agents, etc. In particular, 1,2,5-thiadiazoles and their fused analogues are subjects of fast-growing interest due to their higher significance in the fields of biomedicine and material sciences. OBJECTIVE This study aims to collect detailed medicinal information about aspects of 1,2,5-thiadiazole. METHODS A systemic search has been carried out using PubMed, Google Scholar, CNKI, etc., for relevant studies having the keyword, '1,2,5-thiadiazole'. RESULTS AND CONCLUSION In this mini-review, we have covered known procedures of the synthesis and explored in detail all known advancements of this scaffold concerning to its biological activities.
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Affiliation(s)
- Suraj N Mali
- Department of Pharmaceutical Sciences & Technology, Birla Institute of Technology, Mesra, Jharkhand, India
| | - Anima Pandey
- Department of Pharmaceutical Sciences & Technology, Birla Institute of Technology, Mesra, Jharkhand, India
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Dopaminergic Control of Striatal Cholinergic Interneurons Underlies Cocaine-Induced Psychostimulation. Cell Rep 2021; 31:107527. [PMID: 32320647 DOI: 10.1016/j.celrep.2020.107527] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 02/17/2020] [Accepted: 03/26/2020] [Indexed: 12/11/2022] Open
Abstract
Cocaine drastically elevates dopamine (DA) levels in the striatum, a brain region that is critical to the psychomotor and rewarding properties of the drug. DA signaling regulates intrastriatal circuits connecting medium spiny neurons (MSNs) with afferent fibers and interneurons. While the cocaine-mediated increase in DA signaling on MSNs is well documented, that on cholinergic interneurons (ChIs) has been more difficult to assess. Using combined pharmacological, chemogenetic, and cell-specific ablation approaches, we reveal that the D2R-dependent inhibition of acetylcholine (ACh) signaling is fundamental to cocaine-induced changes in behavior and the striatal genomic response. We show that the D2R-dependent control of striatal ChIs enables the motor, sensitized, and reinforcing properties of cocaine. This study highlights the importance of the DA- and D2R-mediated inhibitory control of ChIs activity in the normal functioning of striatal networks.
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Wang Y, Tan B, Wang Y, Chen Z. Cholinergic Signaling, Neural Excitability, and Epilepsy. Molecules 2021; 26:molecules26082258. [PMID: 33924731 PMCID: PMC8070422 DOI: 10.3390/molecules26082258] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/09/2021] [Accepted: 04/11/2021] [Indexed: 11/16/2022] Open
Abstract
Epilepsy is a common brain disorder characterized by recurrent epileptic seizures with neuronal hyperexcitability. Apart from the classical imbalance between excitatory glutamatergic transmission and inhibitory γ-aminobutyric acidergic transmission, cumulative evidence suggest that cholinergic signaling is crucially involved in the modulation of neural excitability and epilepsy. In this review, we briefly describe the distribution of cholinergic neurons, muscarinic, and nicotinic receptors in the central nervous system and their relationship with neural excitability. Then, we summarize the findings from experimental and clinical research on the role of cholinergic signaling in epilepsy. Furthermore, we provide some perspectives on future investigation to reveal the precise role of the cholinergic system in epilepsy.
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Affiliation(s)
- Yu Wang
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, China; (Y.W.); (B.T.)
| | - Bei Tan
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, China; (Y.W.); (B.T.)
| | - Yi Wang
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, China; (Y.W.); (B.T.)
- Epilepsy Center, Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310058, China
- Correspondence: (Y.W.); (Z.C.); Tel.: +86-5718-661-8660 (Z.C.)
| | - Zhong Chen
- Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province, College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, China; (Y.W.); (B.T.)
- Epilepsy Center, Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310058, China
- Correspondence: (Y.W.); (Z.C.); Tel.: +86-5718-661-8660 (Z.C.)
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Siregar P, Audira G, Feng LY, Lee JH, Santoso F, Yu WH, Lai YH, Li JH, Lin YT, Chen JR, Hsiao CD. Pharmaceutical Assessment Suggests Locomotion Hyperactivity in Zebrafish Triggered by Arecoline Might Be Associated with Multiple Muscarinic Acetylcholine Receptors Activation. Toxins (Basel) 2021; 13:toxins13040259. [PMID: 33916832 PMCID: PMC8066688 DOI: 10.3390/toxins13040259] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/21/2021] [Accepted: 04/01/2021] [Indexed: 12/02/2022] Open
Abstract
Arecoline is one of the nicotinic acid-based alkaloids, which is found in the betel nut. In addition to its function as a muscarinic agonist, arecoline exhibits several adverse effects, such as inducing growth retardation and causing developmental defects in animal embryos, including zebrafish, chicken, and mice. In this study, we aimed to study the potential adverse effects of waterborne arecoline exposure on zebrafish larvae locomotor activity and investigate the possible mechanism of the arecoline effects in zebrafish behavior. The zebrafish behavior analysis, together with molecular docking and the antagonist co-exposure experiment using muscarinic acetylcholine receptor antagonists were conducted. Zebrafish larvae aged 96 h post-fertilization (hpf) were exposed to different concentrations (0.001, 0.01, 0.1, and 1 ppm) of arecoline for 30 min and 24 h, respectively, to find out the effect of arecoline in different time exposures. Locomotor activities were measured and quantified at 120 hpf. The results showed that arecoline caused zebrafish larvae locomotor hyperactivities, even at a very low concentration. For the mechanistic study, we conducted a structure-based molecular docking simulation and antagonist co-exposure experiment to explore the potential interactions between arecoline and eight subtypes, namely, M1a, M2a, M2b, M3a, M3b, M4a, M5a, and M5b, of zebrafish endogenous muscarinic acetylcholine receptors (mAChRs). Arecoline was predicted to show a strong binding affinity to most of the subtypes. We also discovered that the locomotion hyperactivity phenotypes triggered by arecoline could be rescued by co-incubating it with M1 to M4 mAChR antagonists. Taken together, by a pharmacological approach, we demonstrated that arecoline functions as a highly potent hyperactivity-stimulating compound in zebrafish that is mediated by multiple muscarinic acetylcholine receptors.
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Affiliation(s)
- Petrus Siregar
- Department of Chemistry, Chung Yuan Christian University, Chung-Li, Taoyuan City 320314, Taiwan; (P.S.); (G.A.)
- Department of Bioscience Technology, Chung Yuan Christian University, Chung-Li, Taoyuan City 3020314, Taiwan;
| | - Gilbert Audira
- Department of Chemistry, Chung Yuan Christian University, Chung-Li, Taoyuan City 320314, Taiwan; (P.S.); (G.A.)
- Department of Bioscience Technology, Chung Yuan Christian University, Chung-Li, Taoyuan City 3020314, Taiwan;
| | - Ling-Yi Feng
- School of Pharmacy and Ph.D. Program in Toxicology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
- Substance and Behavior Addiction Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Jia-Hau Lee
- Department of Biotechnology, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (J.-H.L.); (W.-H.Y.)
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Fiorency Santoso
- Department of Bioscience Technology, Chung Yuan Christian University, Chung-Li, Taoyuan City 3020314, Taiwan;
| | - Wen-Hao Yu
- Department of Biotechnology, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (J.-H.L.); (W.-H.Y.)
| | - Yu-Heng Lai
- Department of Chemistry, Chinese Culture University, Taipei 11114, Taiwan;
| | - Jih-Heng Li
- School of Pharmacy and Ph.D. Program in Toxicology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
- Substance and Behavior Addiction Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence: (J.-H.L.); (Y.-T.L.); (C.-D.H.)
| | - Ying-Ting Lin
- Department of Biotechnology, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (J.-H.L.); (W.-H.Y.)
- Drug Development & Value Creation Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence: (J.-H.L.); (Y.-T.L.); (C.-D.H.)
| | - Jung-Ren Chen
- Department of Biological Science & Technology, College of Medicine, I-Shou University, Kaohsiung 82445, Taiwan;
| | - Chung-Der Hsiao
- Department of Chemistry, Chung Yuan Christian University, Chung-Li, Taoyuan City 320314, Taiwan; (P.S.); (G.A.)
- Department of Bioscience Technology, Chung Yuan Christian University, Chung-Li, Taoyuan City 3020314, Taiwan;
- Correspondence: (J.-H.L.); (Y.-T.L.); (C.-D.H.)
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Kim SS, Kan H, Hwang KS, Yang JY, Son Y, Shin DS, Lee BH, Ahn SH, Ahn JH, Cho SH, Bae MA. Neurochemical Effects of 4-(2Chloro-4-Fluorobenzyl)-3-(2-Thienyl)-1,2,4-Oxadiazol-5(4H)-One in the Pentylenetetrazole (PTZ)-Induced Epileptic Seizure Zebrafish Model. Int J Mol Sci 2021; 22:1285. [PMID: 33525453 PMCID: PMC7865321 DOI: 10.3390/ijms22031285] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/18/2021] [Accepted: 01/26/2021] [Indexed: 01/03/2023] Open
Abstract
Epilepsy is one of the most common neurological disorders, and it is characterized by spontaneous seizures. In a previous study, we identified 4-(2-chloro-4-fluorobenzyl)-3-(2-thienyl)-1,2,4-oxadiazol-5(4H)-one (GM-90432) as a novel anti-epileptic agent in chemically- or genetically-induced epileptic zebrafish and mouse models. In this study, we investigated the anti-epileptic effects of GM-90432 through neurochemical profiling-based approach to understand the neuroprotective mechanism in a pentylenetetrazole (PTZ)-induced epileptic seizure zebrafish model. GM-90432 effectively improved PTZ-induced epileptic behaviors via upregulation of 5-hydroxytryptamine, 17-β-estradiol, dihydrotestosterone, progesterone, 5α -dihydroprogesterone, and allopregnanolone levels, and downregulation of normetanephrine, gamma-aminobutyric acid, and cortisol levels in brain tissue. GM-90432 also had a protective effect against PTZ-induced oxidative stress and zebrafish death, suggesting that it exhibits biphasic neuroprotective effects via scavenging of reactive oxygen species and anti-epileptic activities in a zebrafish model. In conclusion, our results suggest that neurochemical profiling study could be used to better understand of anti-epileptic mechanism of GM-90432, potentially leading to new drug discovery and development of anti-seizure agents.
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Affiliation(s)
- Seong Soon Kim
- Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea; (S.S.K.); (H.K.); (K.-S.H.); (J.Y.Y.); (Y.S.); (D.-S.S.); (B.H.L.)
| | - Hyemin Kan
- Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea; (S.S.K.); (H.K.); (K.-S.H.); (J.Y.Y.); (Y.S.); (D.-S.S.); (B.H.L.)
| | - Kyu-Seok Hwang
- Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea; (S.S.K.); (H.K.); (K.-S.H.); (J.Y.Y.); (Y.S.); (D.-S.S.); (B.H.L.)
| | - Jung Yoon Yang
- Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea; (S.S.K.); (H.K.); (K.-S.H.); (J.Y.Y.); (Y.S.); (D.-S.S.); (B.H.L.)
| | - Yuji Son
- Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea; (S.S.K.); (H.K.); (K.-S.H.); (J.Y.Y.); (Y.S.); (D.-S.S.); (B.H.L.)
| | - Dae-Seop Shin
- Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea; (S.S.K.); (H.K.); (K.-S.H.); (J.Y.Y.); (Y.S.); (D.-S.S.); (B.H.L.)
| | - Byung Hoi Lee
- Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea; (S.S.K.); (H.K.); (K.-S.H.); (J.Y.Y.); (Y.S.); (D.-S.S.); (B.H.L.)
| | - Se Hwan Ahn
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea; (S.H.A.); (J.H.A.)
| | - Jin Hee Ahn
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea; (S.H.A.); (J.H.A.)
| | - Sung-Hee Cho
- Chemical Analysis Center, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea
| | - Myung Ae Bae
- Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea; (S.S.K.); (H.K.); (K.-S.H.); (J.Y.Y.); (Y.S.); (D.-S.S.); (B.H.L.)
- Department of Medicinal Chemistry and Pharmacology, University of Science & Technology, Daejeon 34113, Korea
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20
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Schrader TO, Xiong Y, Lorenzana AO, Broadhead A, Stebbins KJ, Poon MM, Baccei C, Lorrain DS. Discovery of PIPE-359, a Brain-Penetrant, Selective M 1 Receptor Antagonist with Robust Efficacy in Murine MOG-EAE. ACS Med Chem Lett 2021; 12:155-161. [PMID: 33488977 DOI: 10.1021/acsmedchemlett.0c00626] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 12/22/2020] [Indexed: 02/06/2023] Open
Abstract
The discovery of PIPE-359, a brain-penetrant and selective antagonist of the muscarinic acetylcholine receptor subtype 1 is described. Starting from a literature-reported M1 antagonist, linker replacement and structure-activity relationship investigations of the eastern 1-(pyridinyl)piperazine led to the identification of a novel, potent, and selective antagonist with good MDCKII-MDR1 permeability. Continued semi-iterative positional scanning facilitated improvements in the metabolic and hERG profiles, which ultimately delivered PIPE-359. This advanced drug candidate exhibited robust efficacy in mouse myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalitis (EAE), a preclinical model for multiple sclerosis.
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Affiliation(s)
- Thomas O. Schrader
- Pipeline Therapeutics, 10578 Science Center Drive, Suite 200, San Diego, California 92121, United States
| | - Yifeng Xiong
- Pipeline Therapeutics, 10578 Science Center Drive, Suite 200, San Diego, California 92121, United States
| | - Ariana O. Lorenzana
- Pipeline Therapeutics, 10578 Science Center Drive, Suite 200, San Diego, California 92121, United States
| | - Alexander Broadhead
- Pipeline Therapeutics, 10578 Science Center Drive, Suite 200, San Diego, California 92121, United States
| | - Karin J. Stebbins
- Pipeline Therapeutics, 10578 Science Center Drive, Suite 200, San Diego, California 92121, United States
| | - Michael M. Poon
- Pipeline Therapeutics, 10578 Science Center Drive, Suite 200, San Diego, California 92121, United States
| | - Christopher Baccei
- Pipeline Therapeutics, 10578 Science Center Drive, Suite 200, San Diego, California 92121, United States
| | - Daniel S. Lorrain
- Pipeline Therapeutics, 10578 Science Center Drive, Suite 200, San Diego, California 92121, United States
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21
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Crans RAJ, Ciruela F. Dopaminergic-cholinergic imbalance in movement disorders: a role for the novel striatal dopamine D 2- muscarinic acetylcholine M 1 receptor heteromer. Neural Regen Res 2021; 16:1406-1408. [PMID: 33318429 PMCID: PMC8284294 DOI: 10.4103/1673-5374.300988] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Affiliation(s)
- René A. J Crans
- Laboratory of Toxicology, Department of Bioanalysis, Ghent University, Ghent, Belgium; Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina i Ciències de la Salut, IDIBELL, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Francisco Ciruela
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina i Ciències de la Salut, IDIBELL, Universitat de Barcelona, L'Hospitalet de Llobregat; Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
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22
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Blockade of the M1 muscarinic acetylcholine receptors impairs eyeblink serial feature-positive discrimination learning in mice. PLoS One 2020; 15:e0237451. [PMID: 32790748 PMCID: PMC7425847 DOI: 10.1371/journal.pone.0237451] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 07/27/2020] [Indexed: 11/19/2022] Open
Abstract
The serial feature-positive discrimination task requires the subjects to respond differentially to the identical stimulus depending on the temporal context given by a preceding cue stimulus. In the present study, we examined the involvement of the M1 muscarinic acetylcholine receptors using a selective M1 antagonist VU0255035 in the serial feature-positive discrimination task of eyeblink conditioning in mice. In this task, mice received a 2-s light stimulus as the conditional cue 5 or 6 s before the presentation of a 350-ms tone conditioned stimulus (CS) paired with a 100-ms peri-orbital electrical shock (cued trials), while they did not receive the cue before the presentation of the CS alone (non-cued trials). Each day mice randomly received 30 cued and 30 non-cued trials. We found that VU0255035 impaired acquisition of the conditional discrimination as well as the overall acquisition of the conditioned response (CR) and diminished the difference in onset latency of the CR between the cued and non-cued trials. VU0255035 administration to the control mice after sufficient learning did not impair the pre-acquired conditional discrimination or the CR expression itself. These effects of VU0255035 were almost similar to those with the scopolamine in our previous study, suggesting that among the several types of muscarinic acetylcholine receptors, the M1 receptors may play an important role in the acquisition of the conditional discrimination memory but not in mediating the discrimination itself after the memory had formed in the eyeblink serial feature-positive discrimination learning.
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23
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Silkis IG. Role of Acetylcholine and GABAergic Inhibitory Transmission in Seizure Pattern Generation in Neural Networks Integrating the Neocortex, Hippocampus, Basal Ganglia, and Thalamus. NEUROCHEM J+ 2020. [DOI: 10.1134/s1819712420020129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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24
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The Firing of Theta State-Related Septal Cholinergic Neurons Disrupt Hippocampal Ripple Oscillations via Muscarinic Receptors. J Neurosci 2020; 40:3591-3603. [PMID: 32265261 DOI: 10.1523/jneurosci.1568-19.2020] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 03/11/2020] [Accepted: 03/13/2020] [Indexed: 01/16/2023] Open
Abstract
The septo-hippocampal cholinergic system is critical for hippocampal learning and memory. However, a quantitative description of the in vivo firing patterns and physiological function of medial septal (MS) cholinergic neurons is still missing. In this study, we combined optogenetics with multichannel in vivo recording and recorded MS cholinergic neuron firings in freely behaving male mice for 5.5-72 h. We found that their firing activities were highly correlated with hippocampal theta states. MS cholinergic neurons were highly active during theta-dominant epochs, such as active exploration and rapid eye movement sleep, but almost silent during non-theta epochs, such as slow-wave sleep (SWS). Interestingly, optogenetic activation of these MS cholinergic neurons during SWS suppressed CA1 ripple oscillations. This suppression could be rescued by muscarinic M2 or M4 receptor antagonists. These results suggest the following important physiological function of MS cholinergic neurons: maintaining high hippocampal acetylcholine level by persistent firing during theta epochs, consequently suppressing ripples and allowing theta oscillations to dominate.SIGNIFICANCE STATEMENT The major source of acetylcholine in the hippocampus comes from the medial septum. Early experiments found that lesions to the MS result in the disappearance of hippocampal theta oscillation, which leads to speculation that the septo-hippocampal cholinergic projection contributing to theta oscillation. In this article, by long-term recording of MS cholinergic neurons, we found that they show a theta state-related firing pattern. However, optogenetically activating these neurons shows little effect on theta rhythm in the hippocampus. Instead, we found that activating MS cholinergic neurons during slow-wave sleep could suppress hippocampal ripple oscillations. This suppression is mediated by muscarinic M2 and M4 receptors.
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25
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Crans RAJ, Wouters E, Valle-León M, Taura J, Massari CM, Fernández-Dueñas V, Stove CP, Ciruela F. Striatal Dopamine D 2-Muscarinic Acetylcholine M 1 Receptor-Receptor Interaction in a Model of Movement Disorders. Front Pharmacol 2020; 11:194. [PMID: 32231561 PMCID: PMC7083216 DOI: 10.3389/fphar.2020.00194] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 02/11/2020] [Indexed: 12/17/2022] Open
Abstract
Parkinson’s disease (PD) is a neurodegenerative disorder characterized by motor control deficits, which is associated with the loss of striatal dopaminergic neurons from the substantia nigra. In parallel to dopaminergic denervation, there is an increase of acetylcholine within the striatum, resulting in a striatal dopaminergic–cholinergic neurotransmission imbalance. Currently, available PD pharmacotherapy (e.g., prodopaminergic drugs) does not reinstate the altered dopaminergic–cholinergic balance. In addition, it can eventually elicit cholinergic-related adverse effects. Here, we investigated the interplay between dopaminergic and cholinergic systems by assessing the physical and functional interaction of dopamine D2 and muscarinic acetylcholine M1 receptors (D2R and M1R, respectively), both expressed at striatopallidal medium spiny neurons. First, we provided evidence for the existence of D2R–M1R complexes via biochemical (i.e., co-immunoprecipitation) and biophysical (i.e., BRET1 and NanoBiT®) assays, performed in transiently transfected HEK293T cells. Subsequently, a D2R–M1R co-distribution in the mouse striatum was observed through double-immunofluorescence staining and AlphaLISA® immunoassay. Finally, we evaluated the functional interplay between both receptors via behavioral studies, by implementing the classical acute reserpine pharmacological animal model of experimental parkinsonism. Reserpinized mice were administered with a D2R-selective agonist (sumanirole) and/or an M1R-selective antagonist (VU0255035), and alterations in PD-related behavioral tasks (i.e., locomotor activity) were evaluated. Importantly, VU0255035 (10 mg/kg) potentiated the antiparkinsonian-like effects (i.e., increased locomotor activity and decreased catalepsy) of an ineffective sumanirole dose (3 mg/kg). Altogether, our data suggest the existence of putative striatal D2R/M1R heteromers, which might be a relevant target to manage PD motor impairments with fewer adverse effects.
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Affiliation(s)
- René A J Crans
- Laboratory of Toxicology, Department of Bioanalysis, Ghent University, Ghent, Belgium.,Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Elise Wouters
- Laboratory of Toxicology, Department of Bioanalysis, Ghent University, Ghent, Belgium
| | - Marta Valle-León
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
| | - Jaume Taura
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
| | - Caio M Massari
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Programa de Poìs-graduação em Bioquiìmica, Centro de Ciencias Bioloìgicas, Universidade Federal de Santa Catarina, Florianoìpolis, Brazil
| | - Víctor Fernández-Dueñas
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
| | - Christophe P Stove
- Laboratory of Toxicology, Department of Bioanalysis, Ghent University, Ghent, Belgium
| | - Francisco Ciruela
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
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26
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Moran SP, Xiang Z, Doyle CA, Maksymetz J, Lv X, Faltin S, Fisher NM, Niswender CM, Rook JM, Lindsley CW, Conn PJ. Biased M 1 receptor-positive allosteric modulators reveal role of phospholipase D in M 1-dependent rodent cortical plasticity. Sci Signal 2019; 12:12/610/eaax2057. [PMID: 31796631 DOI: 10.1126/scisignal.aax2057] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Highly selective, positive allosteric modulators (PAMs) of the M1 subtype of muscarinic acetylcholine receptor have emerged as an exciting new approach to potentially improve cognitive function in patients suffering from Alzheimer's disease and schizophrenia. Discovery programs have produced a structurally diverse range of M1 receptor PAMs with distinct pharmacological properties, including different extents of agonist activity and differences in signal bias. This includes biased M1 receptor PAMs that can potentiate coupling of the receptor to activation of phospholipase C (PLC) but not phospholipase D (PLD). However, little is known about the role of PLD in M1 receptor signaling in native systems, and it is not clear whether biased M1 PAMs display differences in modulating M1-mediated responses in native tissue. Using PLD inhibitors and PLD knockout mice, we showed that PLD was necessary for the induction of M1-dependent long-term depression (LTD) in the prefrontal cortex (PFC). Furthermore, biased M1 PAMs that did not couple to PLD not only failed to potentiate orthosteric agonist-induced LTD but also blocked M1-dependent LTD in the PFC. In contrast, biased and nonbiased M1 PAMs acted similarly in potentiating M1-dependent electrophysiological responses that were PLD independent. These findings demonstrate that PLD plays a critical role in the ability of M1 PAMs to modulate certain central nervous system (CNS) functions and that biased M1 PAMs function differently in brain regions implicated in cognition.
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Affiliation(s)
- Sean P Moran
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232, USA.,Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - Zixiu Xiang
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - Catherine A Doyle
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - James Maksymetz
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - Xiaohui Lv
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - Sehr Faltin
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - Nicole M Fisher
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - Colleen M Niswender
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA.,Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN 37240, USA
| | - Jerri M Rook
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232, USA.,Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - Craig W Lindsley
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA.,Department of Chemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - P Jeffrey Conn
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232, USA. .,Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA.,Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN 37240, USA
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27
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Moran SP, Maksymetz J, Conn PJ. Targeting Muscarinic Acetylcholine Receptors for the Treatment of Psychiatric and Neurological Disorders. Trends Pharmacol Sci 2019; 40:1006-1020. [PMID: 31711626 DOI: 10.1016/j.tips.2019.10.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 10/17/2019] [Accepted: 10/17/2019] [Indexed: 12/12/2022]
Abstract
Muscarinic acetylcholine receptors (mAChR) play important roles in regulating complex behaviors such as cognition, movement, and reward, making them ideally situated as potential drug targets for the treatment of several brain disorders. Recent advances in the discovery of subtype-selective allosteric modulators for mAChRs has provided an unprecedented opportunity for highly specific modulation of signaling by individual mAChR subtypes in the brain. Recently, mAChR allosteric modulators have entered clinical development for Alzheimer's disease (AD) and schizophrenia, and have potential utility for other brain disorders. However, mAChR allosteric modulators can display a diverse array of pharmacological properties, and a more nuanced understanding of the mAChR will be necessary to best translate preclinical findings into successful clinical treatments.
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Affiliation(s)
- Sean P Moran
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - James Maksymetz
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA
| | - P Jeffrey Conn
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA.
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28
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Melendez-Zaidi AE, Lakshminarasimhah H, Surmeier DJ. Cholinergic modulation of striatal nitric oxide-producing interneurons. Eur J Neurosci 2019; 50:3713-3731. [PMID: 31340071 DOI: 10.1111/ejn.14528] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 07/07/2019] [Accepted: 07/15/2019] [Indexed: 01/17/2023]
Abstract
Striatal GABAergic interneurons that express nitric oxide synthase-so-called low-threshold spike interneurons (LTSIs)-play several key roles in the striatum. But what drives the activity of these interneurons is less well defined. To fill this gap, a combination of monosynaptic rabies virus mapping (msRVm), electrophysiological and optogenetic approaches were used in transgenic mice in which LTSIs expressed either Cre recombinase or a fluorescent reporter. The rabies virus studies revealed a striking similarity in the afferent connectomes of LTSIs and neighboring cholinergic interneurons, particularly regarding connections arising from the parafascicular nucleus of the thalamus and cingulate cortex. While optogenetic stimulation of cingulate inputs excited both cholinergic interneurons and LTSIs, thalamic stimulation excited cholinergic interneurons, but inhibited LTSIs. This inhibition was dependent on cholinergic interneurons and had two components: a previously described GABAergic element and one that was mediated by M4 muscarinic acetylcholine receptors. In addition to this phasic signal, cholinergic interneurons tonically excited LTSIs through a distinct, M1 muscarinic acetylcholine receptor pathway. This coordinated cholinergic modulation of LTSIs predisposed them to rhythmically burst in response to phasic thalamic activity, potentially reconfiguring striatal circuitry in response to salient environmental stimuli.
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Affiliation(s)
- Alexandria E Melendez-Zaidi
- Department of Physiology, Feinberg School of Medicine, Chicago, IL, USA.,Medical Scientist Training Program, Feinberg School of Medicine, Chicago, IL, USA.,Department of Pediatrics, Division of Neurology and Developmental Neuroscience, Texas Children's Hospital/Baylor College of Medicine, Houston, TX, USA
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29
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Soares JI, Da Costa C, Ferreira MH, Andrade PA, Maia GH, Lukoyanov NV. Partial depletion of septohippocampal cholinergic cells reduces seizure susceptibility, but does not mitigate hippocampal neurodegeneration in the kainate model of epilepsy. Brain Res 2019; 1717:235-246. [DOI: 10.1016/j.brainres.2019.04.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 04/22/2019] [Accepted: 04/23/2019] [Indexed: 02/06/2023]
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30
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Maksymetz J, Joffe ME, Moran SP, Stansley BJ, Li B, Temple K, Engers DW, Lawrence JJ, Lindsley CW, Conn PJ. M 1 Muscarinic Receptors Modulate Fear-Related Inputs to the Prefrontal Cortex: Implications for Novel Treatments of Posttraumatic Stress Disorder. Biol Psychiatry 2019; 85:989-1000. [PMID: 31003787 PMCID: PMC6555658 DOI: 10.1016/j.biopsych.2019.02.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 02/15/2019] [Accepted: 02/18/2019] [Indexed: 12/20/2022]
Abstract
BACKGROUND The prefrontal cortex (PFC) integrates information from multiple inputs to exert top-down control allowing for appropriate responses in a given context. In psychiatric disorders such as posttraumatic stress disorder, PFC hyperactivity is associated with inappropriate fear in safe situations. We previously reported a form of muscarinic acetylcholine receptor (mAChR)-dependent long-term depression in the PFC that we hypothesize is involved in appropriate fear responding and could serve to reduce cortical hyperactivity following stress. However, it is unknown whether this long-term depression occurs at fear-related inputs. METHODS Using optogenetics with extracellular and whole-cell electrophysiology, we assessed the effect of mAChR activation on the synaptic strength of specific PFC inputs. We used selective pharmacological tools to assess the involvement of M1 mAChRs in conditioned fear extinction in control mice and in the stress-enhanced fear-learning model. RESULTS M1 mAChR activation induced long-term depression at inputs from the ventral hippocampus and basolateral amygdala but not from the mediodorsal nucleus of the thalamus. We found that systemic M1 mAChR antagonism impaired contextual fear extinction. Treatment with an M1 positive allosteric modulator enhanced contextual fear extinction consolidation in stress-enhanced fear learning-conditioned mice. CONCLUSIONS M1 mAChRs dynamically modulate synaptic transmission at two PFC inputs whose activity is necessary for fear extinction, and M1 mAChR function is required for proper contextual fear extinction. Furthermore, an M1 positive allosteric modulator enhanced the consolidation of fear extinction in the stress-enhanced fear-learning model, suggesting that M1 positive allosteric modulators may provide a novel treatment strategy to facilitate exposure therapy in the clinic for the treatment of posttraumatic stress disorder.
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Affiliation(s)
- James Maksymetz
- Department of Pharmacology,Vanderbilt Center for Neuroscience Drug Discovery
| | - Max E. Joffe
- Department of Pharmacology,Vanderbilt Center for Neuroscience Drug Discovery
| | - Sean P. Moran
- Department of Pharmacology,Vanderbilt Center for Neuroscience Drug Discovery,Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN
| | - Branden J. Stansley
- Department of Pharmacology,Vanderbilt Center for Neuroscience Drug Discovery
| | | | - Kayla Temple
- Vanderbilt Center for Neuroscience Drug Discovery
| | - Darren W. Engers
- Department of Pharmacology,Vanderbilt Center for Neuroscience Drug Discovery
| | - J. Josh Lawrence
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX
| | - Craig W. Lindsley
- Department of Pharmacology,Vanderbilt Center for Neuroscience Drug Discovery,Department of Chemistry, Vanderbilt University, Nashville, TN
| | - P. Jeffrey Conn
- Department of Pharmacology,Vanderbilt Center for Neuroscience Drug Discovery,Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN,Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN,Corresponding Author: P. Jeffrey Conn, Ph.D., Lee E. Limbird Professor of Pharmacology, Director, Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, 1205 Light Hall, Nashville, TN 37232-0697, Tel: 615-936-2189, Fax: 615-343-3088,
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Hoffman KM, Eisen MR, Chandler JK, Nelson MR, Johnson EA, McNutt PM. Retrograde activation of CB1R by muscarinic receptors protects against central organophosphorus toxicity. Neuropharmacology 2019; 155:113-120. [PMID: 31132436 DOI: 10.1016/j.neuropharm.2019.05.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 04/18/2019] [Accepted: 05/21/2019] [Indexed: 11/17/2022]
Abstract
The acute toxicity of organophosphorus-based compounds is primarily a result of acetylcholinesterase inhibition in the central and peripheral nervous systems. The resulting cholinergic crisis manifests as seizure, paralysis, respiratory failure and neurotoxicity. Though overstimulation of muscarinic receptors is the mechanistic basis of central organophosphorus (OP) toxicities, short-term changes in synapse physiology that precede OP-induced seizures have not been investigated in detail. To study acute effects of OP exposure on synaptic function, field excitatory postsynaptic potentials (fEPSPs) were recorded from Schaffer collateral synapses in the mouse hippocampus CA1 stratum radiatum during perfusion with various OP compounds. Administration of the OPs paraoxon, soman or VX rapidly and stably depressed fEPSPs via a presynaptic mechanism, while the non-OP proconvulsant tetramethylenedisulfotetramine had no effect on fEPSP amplitudes. OP-induced presynaptic long-term depression manifested prior to interictal spiking, occurred independent of recurrent firing, and did not require NMDA receptor currents, suggesting that it was not mediated by activity-dependent calcium uptake. Pharmacological dissection revealed that the presynaptic endocannabinoid type 1 receptor (CB1R) as well as postsynaptic M1 and M3 muscarinic acetylcholine receptors were necessary for OP-LTD. Administration of CB1R antagonists significantly reduced survival in mice after a soman challenge, revealing an acute protective role for endogenous CB1R signaling during OP exposure. Collectively these data demonstrate that the endocannabinoid system alters glutamatergic synaptic function during the acute response to OP acetylcholinesterase inhibitors.
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Affiliation(s)
- Katie M Hoffman
- Biological Sciences, Lehigh University, 27 Memorial Drive West, Bethlehem, PA, 18015, USA
| | - Margaret R Eisen
- Department of Neuroscience, United States Army Medical Research Institute of Chemical Defense, 2900 Ricketts Point Road, Gunpowder, MD, 21010, USA
| | - Jessica K Chandler
- Department of Neuroscience, United States Army Medical Research Institute of Chemical Defense, 2900 Ricketts Point Road, Gunpowder, MD, 21010, USA
| | - Marian R Nelson
- Department of Neuroscience, United States Army Medical Research Institute of Chemical Defense, 2900 Ricketts Point Road, Gunpowder, MD, 21010, USA
| | - Erik A Johnson
- Department of Neuroscience, United States Army Medical Research Institute of Chemical Defense, 2900 Ricketts Point Road, Gunpowder, MD, 21010, USA
| | - Patrick M McNutt
- Department of Neuroscience, United States Army Medical Research Institute of Chemical Defense, 2900 Ricketts Point Road, Gunpowder, MD, 21010, USA.
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Thorn CA, Moon J, Bourbonais CA, Harms J, Edgerton JR, Stark E, Steyn SJ, Butter CR, Lazzaro JT, O’Connor RE, Popiolek M. Striatal, Hippocampal, and Cortical Networks Are Differentially Responsive to the M4- and M1-Muscarinic Acetylcholine Receptor Mediated Effects of Xanomeline. ACS Chem Neurosci 2019; 10:1753-1764. [PMID: 30480428 DOI: 10.1021/acschemneuro.8b00625] [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] [Indexed: 12/13/2022] Open
Abstract
Preclinical and clinical data suggest that muscarinic acetylcholine receptor activation may be therapeutically beneficial for the treatment of schizophrenia and Alzheimer's diseases. This is best exemplified by clinical observations with xanomeline, the efficacy of which is thought to be mediated through co-activation of the M1 and M4 muscarinic acetylcholine receptors (mAChRs). Here we examined the impact of treatment with xanomeline and compared it to the actions of selective M1 and M4 mAChR activators on in vivo intracellular signaling cascades in mice, including 3'-5'-cyclic adenosine monophosphate response element binding protein (CREB) phosphorylation and inositol phosphate-1 (IP1) accumulation in the striatum, hippocampus, and prefrontal cortex. We additionally assessed the effects of xanomeline on hippocampal electrophysiological signatures in rats using ex vivo recordings from CA1 (Cornu Ammonis 1) as well as in vivo hippocampal theta. As expected, xanomeline's effects across these readouts were consistent with activation of both M1 and M4 mAChRs; however, differences were observed across different brain regions, suggesting non-uniform activation of these receptor subtypes in the central nervous system. Interestingly, despite having nearly equal in vitro potency at the M1 and the M4 mAChRs, during in vivo assays xanomeline produced M4-like effects at significantly lower brain exposures than those at which M1-like effects were observed. Our results raise the possibility that clinical efficacy observed with xanomeline was driven, in part, through its non-uniform activation of mAChR subtypes in the central nervous system and, at lower doses, through preferential agonism of the M4 mAChR.
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Affiliation(s)
| | | | | | | | | | | | | | | | - John T. Lazzaro
- Primary Pharmacology Group, Pfizer Worldwide Research and Development, Groton, Connecticut 06340, United States
| | - Rebecca E. O’Connor
- Primary Pharmacology Group, Pfizer Worldwide Research and Development, Groton, Connecticut 06340, United States
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Xiong CH, Liu MG, Zhao LX, Chen MW, Tang L, Yan YH, Chen HZ, Qiu Y. M1 muscarinic receptors facilitate hippocampus-dependent cognitive flexibility via modulating GluA2 subunit of AMPA receptors. Neuropharmacology 2019; 146:242-251. [DOI: 10.1016/j.neuropharm.2018.12.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 11/29/2018] [Accepted: 12/05/2018] [Indexed: 12/31/2022]
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Inoue M, Harada K, Matsui M, Matsuoka H. Differences among muscarinic agonists in M 1 receptor-mediated nonselective cation channel activation and TASK1 channel inhibition in adrenal medullary cells. Eur J Pharmacol 2019; 843:104-112. [PMID: 30452911 DOI: 10.1016/j.ejphar.2018.11.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 11/15/2018] [Accepted: 11/15/2018] [Indexed: 10/27/2022]
Abstract
Muscarinic receptor stimulation induces depolarizing inward currents and catecholamine secretion in adrenal medullary (AM) cells from various mammals. In guinea-pig AM cells muscarine and oxotremorine at concentrations ≤ 1 μM produce activation of nonselective cation channels with a similar potency and efficacy, whereas muscarine at higher concentrations produces not only nonselective cation channel activation, but also TASK1 channel inhibition. In rat AM cells, the muscarinic M1 receptor is involved in TASK1 channel inhibition in response to muscarinic agonists, and the efficacy of oxotremorine is half that of muscarine. These pharmacological findings might indicate that different muscarinic receptor subtypes are responsible for the regulation of nonselective cation and TASK1 channel activities. The present study aimed to determine the muscarinic receptor subtypes involved in nonselective cation channel activation in guinea-pig and mouse AM cells. The inward current evoked by 1 μM muscarine was completely suppressed by 100 μM quinine, whereas 30 μM muscarine-induced inward currents were comprised of quinine-sensitive and -insensitive components. The electrophysiological and pharmacological properties of the muscarine-induced currents indicated that the quinine-sensitive and insensitive components are due to nonselective cation channel activation and TASK1 channel inhibition, respectively. Muscarine at 30 μM failed to induce any current in AM cells treated with muscarinic toxin 7 or genetically deleted of the M1 receptor. The KD value of VU0255035 against the muscarinic receptor mediating nonselective cation channel activation was 17.5 nM. These results indicate that the M1 receptor mediates nonselective cation channel activation as well as TASK1 channel inhibition.
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Affiliation(s)
- Masumi Inoue
- Department of Cell and Systems Physiology, University of Occupational and Environmental Health School of Medicine, Kitakyushu 807-8555, Japan.
| | - Keita Harada
- Department of Cell and Systems Physiology, University of Occupational and Environmental Health School of Medicine, Kitakyushu 807-8555, Japan
| | | | - Hidetada Matsuoka
- Department of Cell and Systems Physiology, University of Occupational and Environmental Health School of Medicine, Kitakyushu 807-8555, Japan
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Gq-Coupled Muscarinic Receptor Enhancement of KCNQ2/3 Channels and Activation of TRPC Channels in Multimodal Control of Excitability in Dentate Gyrus Granule Cells. J Neurosci 2018; 39:1566-1587. [PMID: 30593498 DOI: 10.1523/jneurosci.1781-18.2018] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 12/17/2018] [Accepted: 12/20/2018] [Indexed: 12/21/2022] Open
Abstract
KCNQ (Kv7, "M-type") K+ channels and TRPC (transient receptor potential, "canonical") cation channels are coupled to neuronal discharge properties and are regulated via Gq/11-protein-mediated signals. Stimulation of Gq/11-coupled receptors both consumes phosphatidylinositol 4,5-bisphosphate (PIP2) via phosphalipase Cβ hydrolysis and stimulates PIP2 synthesis via rises in Ca2+ i and other signals. Using brain-slice electrophysiology and Ca2+ imaging from male and female mice, we characterized threshold K+ currents in dentate gyrus granule cells (DGGCs) and CA1 pyramidal cells, the effects of Gq/11-coupled muscarinic M1 acetylcholine (M1R) stimulation on M current and on neuronal discharge properties, and elucidated the intracellular signaling mechanisms involved. We observed disparate signaling cascades between DGGCs and CA1 neurons. DGGCs displayed M1R enhancement of M-current, rather than suppression, due to stimulation of PIP2 synthesis, which was paralleled by increased PIP2-gated G-protein coupled inwardly rectifying K+ currents as well. Deficiency of KCNQ2-containing M-channels ablated the M1R-induced enhancement of M-current in DGGCs. Simultaneously, M1R stimulation in DGGCs induced robust increases in [Ca2+]i, mostly due to TRPC currents, consistent with, and contributing to, neuronal depolarization and hyperexcitability. CA1 neurons did not display such multimodal signaling, but rather M current was suppressed by M1R stimulation in these cells, similar to the previously described actions of M1R stimulation on M-current in peripheral ganglia that mostly involves PIP2 depletion. Therefore, these results point to a pleiotropic network of cholinergic signals that direct cell-type-specific, precise control of hippocampal function with strong implications for hyperexcitability and epilepsy.SIGNIFICANCE STATEMENT At the neuronal membrane, protein signaling cascades consisting of ion channels and metabotropic receptors govern the electrical properties and neurotransmission of neuronal networks. Muscarinic acetylcholine receptors are G-protein-coupled metabotropic receptors that control the excitability of neurons through regulating ion channels, intracellular Ca2+ signals, and other second-messenger cascades. We have illuminated previously unknown actions of muscarinic stimulation on the excitability of hippocampal principal neurons that include M channels, TRPC (transient receptor potential, "canonical") cation channels, and powerful regulation of lipid metabolism. Our results show that these signaling pathways, and mechanisms of excitability, are starkly distinct between peripheral ganglia and brain, and even between different principal neurons in the hippocampus.
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The high efficacy of muscarinic M4 receptor in D1 medium spiny neurons reverses striatal hyperdopaminergia. Neuropharmacology 2018; 146:74-83. [PMID: 30468798 DOI: 10.1016/j.neuropharm.2018.11.029] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 11/07/2018] [Accepted: 11/20/2018] [Indexed: 01/24/2023]
Abstract
The opposing action of dopamine and acetylcholine has long been known to play an important role in basal ganglia physiology. However, the quantitative analysis of dopamine and acetylcholine signal interaction has been difficult to perform in the native context because the striatum comprises mainly two subtypes of medium-sized spiny neurons (MSNs) on which these neuromodulators exert different actions. We used biosensor imaging in live brain slices of dorsomedial striatum to monitor changes in intracellular cAMP at the level of individual MSNs. We observed that the muscarinic agonist oxotremorine decreases cAMP selectively in the MSN subpopulation that also expresses D1 dopamine receptors, an action mediated by the M4 muscarinic receptor. This receptor has a high efficacy on cAMP signaling and can shut down the positive cAMP response induced by dopamine, at acetylcholine concentrations which are consistent with physiological levels. This supports our prediction based on theoretical modeling that acetylcholine could exert a tonic inhibition on striatal cAMP signaling, thus supporting the possibility that a pause in acetylcholine release is required for phasic dopamine to transduce a cAMP signal in D1 MSNs. In vivo experiments with acetylcholinesterase inhibitors donepezil and tacrine, as well as with the positive allosteric modulators of M4 receptor VU0152100 and VU0010010 show that this effect is sufficient to reverse the increased locomotor activity of DAT-knockout mice. This suggests that M4 receptors could be a novel therapeutic target to treat hyperactivity disorders.
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Roth TC, Krochmal AR. Of molecules, memories and migration: M1 acetylcholine receptors facilitate spatial memory formation and recall during migratory navigation. Proc Biol Sci 2018; 285:rspb.2018.1904. [PMID: 30429306 PMCID: PMC6253372 DOI: 10.1098/rspb.2018.1904] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 10/24/2018] [Indexed: 02/03/2023] Open
Abstract
Many animals use complex cognitive processes, including the formation and recall of memories, for successful navigation. However, the developmental and neurological processes underlying these cognitive aspects of navigation are poorly understood. To address the importance of the formation and recollection of memories during navigation, we pharmacologically manipulated turtles (Chrysemys picta) that navigate long distances using precise, complex paths learned during a juvenile critical period. We treated freely navigating turtles both within and outside of their critical learning period with a specific M1 acetylcholine receptor antagonist, a drug known to disrupt spatial cognition. Experienced adult turtles lost all navigational ability under the influence of the drug, while naive juveniles navigated successfully. We retested these same juveniles the following year (after they had passed their critical period). The juveniles that initially navigated successfully under the influence of the antagonist (but were unable to form spatial memories) were unable to do so subsequently. However, the control animals (who had the opportunity to form memories previously) exhibited typical navigational precision. These results suggest that the formation of spatial memories for navigation occur during a critical period, and successful navigation after the critical period is dependent upon the recall of such memories.
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Affiliation(s)
- Timothy C Roth
- Department of Psychology, Franklin and Marshall College, PO Box 3003, Lancaster, PA 17603, USA
| | - Aaron R Krochmal
- Department of Biology, Washington College, 300 Washington Avenue, Chestertown, MD 21620, USA
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Moran SP, Cho HP, Maksymetz J, Remke DH, Hanson RM, Niswender CM, Lindsley CW, Rook JM, Conn PJ. PF-06827443 Displays Robust Allosteric Agonist and Positive Allosteric Modulator Activity in High Receptor Reserve and Native Systems. ACS Chem Neurosci 2018; 9:2218-2224. [PMID: 29683646 DOI: 10.1021/acschemneuro.8b00106] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Positive allosteric modulators (PAMs) of the M1 subtype of muscarinic acetylcholine receptor have attracted intense interest as an exciting new approach for improving the cognitive deficits in schizophrenia and Alzheimer's disease. Recent evidence suggests that the presence of intrinsic agonist activity of some M1 PAMs may reduce efficacy and contribute to adverse effect liability. However, the M1 PAM PF-06827443 was reported to have only weak agonist activity at human M1 receptors but produced M1-dependent adverse effects. We now report that PF-06827443 is an allosteric agonist in cell lines expressing rat, dog, and human M1 and use of inducible cell lines shows that agonist activity of PF-06827443 is dependent on receptor reserve. Furthermore, PF-06827443 is an agonist in native tissue preparations and induces behavioral convulsions in mice similar to other ago-PAMs. These findings suggest that PF-06827443 is a robust ago-PAM, independent of species, in cell lines and native systems.
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Affiliation(s)
- Sean P. Moran
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee 37232, United States
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, United States
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Hyekyung P. Cho
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, United States
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - James Maksymetz
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, United States
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Daniel H. Remke
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, United States
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Ryan M. Hanson
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Colleen M. Niswender
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, United States
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232, United States
- Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee 37240, United States
| | - Craig W. Lindsley
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, United States
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee 37232, United States
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Jerri M. Rook
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee 37232, United States
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, United States
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - P. Jeffrey Conn
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee 37232, United States
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, United States
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee 37232, United States
- Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee 37240, United States
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M 1-positive allosteric modulators lacking agonist activity provide the optimal profile for enhancing cognition. Neuropsychopharmacology 2018; 43:1763-1771. [PMID: 29581537 PMCID: PMC6006294 DOI: 10.1038/s41386-018-0033-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 02/11/2018] [Accepted: 02/16/2018] [Indexed: 11/09/2022]
Abstract
Highly selective positive allosteric modulators (PAMs) of the M1 subtype of muscarinic acetylcholine receptor have emerged as an exciting new approach for improving cognitive function in patients suffering from Alzheimer's disease and schizophrenia. However, excessive activation of M1 is known to induce seizure activity and have actions in the prefrontal cortex (PFC) that could impair cognitive function. We now report a series of pharmacological, electrophysiological, and behavioral studies in which we find that recently reported M1 PAMs, PF-06764427 and MK-7622, have robust agonist activity in cell lines and agonist effects in the mouse PFC, and have the potential to overactivate the M1 receptor and disrupt PFC function. In contrast, structurally distinct M1 PAMs (VU0453595 and VU0550164) are devoid of agonist activity in cell lines and maintain activity dependence of M1 activation in the PFC. Consistent with the previously reported effect of PF-06764427, the ago-PAM MK-7622 induces severe behavioral convulsions in mice. In contrast, VU0453595 does not induce behavioral convulsions at doses well above those required for maximal efficacy in enhancing cognitive function. Furthermore, in contrast to the robust efficacy of VU0453595, the ago-PAM MK-7622 failed to improve novel object recognition, a rodent assay of cognitive function. These findings suggest that in vivo cognition-enhancing efficacy of M1 PAMs can be observed with PAMs lacking intrinsic agonist activity and that intrinsic agonist activity of M1 PAMs may contribute to adverse effects and reduced efficacy in improving cognitive function.
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Zhao L, Ge Y, Xiong C, Tang L, Yan Y, Law P, Qiu Y, Chen H. M1 muscarinic receptor facilitates cognitive function by interplay with AMPA receptor GluAl subunit. FASEB J 2018; 32:4247-4257. [DOI: 10.1096/fj.201800029r] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Lan‐Xue Zhao
- Department of Pharmacology and Chemical BiologyInstitute of Medical SciencesShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Yan‐Hui Ge
- Department of Pharmacology and Chemical BiologyInstitute of Medical SciencesShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Cai‐Hong Xiong
- Department of Pharmacology and Chemical BiologyInstitute of Medical SciencesShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Ling Tang
- Department of Pharmacology and Chemical BiologyInstitute of Medical SciencesShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Ying‐Hui Yan
- Department of Pharmacology and Chemical BiologyInstitute of Medical SciencesShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Ping‐Yee Law
- Department of PharmacologyUniversity of MinnesotaMinneapolisMinnesotaUSA
| | - Yu Qiu
- Department of Pharmacology and Chemical BiologyInstitute of Medical SciencesShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Hong‐Zhuan Chen
- Department of Pharmacology and Chemical BiologyInstitute of Medical SciencesShanghai Jiao Tong University School of MedicineShanghaiChina
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Current status of muscarinic M1 and M4 receptors as drug targets for neurodegenerative diseases. Neuropharmacology 2018; 136:449-458. [PMID: 29374561 DOI: 10.1016/j.neuropharm.2018.01.028] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 01/09/2018] [Accepted: 01/21/2018] [Indexed: 01/17/2023]
Abstract
The cholinergic signalling system has been an attractive pathway to seek targets for modulation of arousal, cognition, and attention which are compromised in neurodegenerative and neuropsychiatric diseases. The acetylcholine muscarinic receptor M1 and M4 subtypes which are highly expressed in the central nervous system, in cortex, hippocampus and striatum, key areas of cognitive and neuropsychiatric control, have received particular attention. Historical muscarinic drug development yielded first generation agonists with modest selectivity for these two receptor targets over M2 and M3 receptors, the major peripheral sub-types hypothesised to underlie the dose-limiting clinical side effects. More recent compound screening and medicinal chemistry optimization of orthosteric and allosteric agonists, and positive allosteric modulators binding to sites distinct from the highly homologous acetylcholine binding pocket have yielded a collection of highly selective tool compounds for preclinical validation studies. Several M1 selective ligands have progressed to early clinical development and in time will hopefully lead to useful therapeutics for treating symptoms of Alzheimer's disease and related disorders. This article is part of the Special Issue entitled 'Neuropharmacology on Muscarinic Receptors'.
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Activity-Dependent Brain-Derived Neurotrophic Factor Release Is Required for the Rapid Antidepressant Actions of Scopolamine. Biol Psychiatry 2018; 83:29-37. [PMID: 28751069 PMCID: PMC5705490 DOI: 10.1016/j.biopsych.2017.06.017] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 06/09/2017] [Accepted: 06/12/2017] [Indexed: 12/28/2022]
Abstract
BACKGROUND Brain-derived neurotrophic factor (BDNF) plays a key role in the pathophysiology and treatment of depression. Recent clinical studies demonstrate that scopolamine, a nonselective muscarinic acetylcholine receptor antagonist, produces rapid antidepressant effects in patients with depression. Rodent studies demonstrate that scopolamine increases glutamate transmission and synaptogenesis in the medial prefrontal cortex (mPFC). Here we tested the hypothesis that activity-dependent BDNF release within the mPFC is necessary for the antidepressant actions of scopolamine. METHODS Behavioral effects of scopolamine were assessed in BDNF Val/Met knock-in mice, in which BDNF processing and release are impaired. In addition, intra-mPFC infusion of a BDNF-neutralizing antibody was performed to test the necessity of BDNF release in driving scopolamine-induced behavioral responses. Further in vivo and in vitro experiments were performed to delineate BDNF-dependent mechanisms underlying the effects of scopolamine. RESULTS We found that BDNF Met/Met mice have attenuated responses to scopolamine and that anti-BDNF antibody infusions into the mPFC prevented the antidepressant-like behavioral effects of scopolamine. In vitro experiments show that scopolamine rapidly stimulates BDNF release and tropomyosin receptor kinase B-extracellular signal-regulated kinase signaling. Moreover, these effects require alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor activation and are blocked by neuronal silencing. Importantly, pretreatment with verapamil prevented scopolamine-induced behavioral responses and BDNF-tropomyosin receptor kinase B signaling, suggesting that these effects are dependent on activation of voltage-dependent calcium channels. CONCLUSIONS The results identify an essential role for activity-dependent BDNF release in the rapid antidepressant effects of scopolamine. Attenuation of responses in BDNF Met mice indicates that patients with the Met allele may be less responsive to scopolamine.
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Miyauchi M, Neugebauer NM, Sato T, Ardehali H, Meltzer HY. Muscarinic receptor signaling contributes to atypical antipsychotic drug reversal of the phencyclidine-induced deficit in novel object recognition in rats. J Psychopharmacol 2017; 31:1588-1604. [PMID: 28946779 DOI: 10.1177/0269881117731278] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Enhancement of cholinergic function via muscarinic acetylcholine receptor M1 agonism improves cognition in some schizophrenia patients. Most atypical antipsychotic drugs, including clozapine and its active metabolite, N-desmethylclozapine, and lurasidone, enhance the release of acetylcholine in key brain regions involved in cognition (e.g. hippocampus). We determined the effect of muscarinic acetylcholine receptor M1 stimulation on novel object recognition and its contribution to the ability of atypical antipsychotic drugs to reverse the novel object recognition deficit in rats withdrawn from subchronic phencyclidine, a rodent model of cognitive impairment in schizophrenia. In control rats, the non-specific muscarinic acetylcholine receptor antagonist, scopolamine, and the M1 selective antagonist, VU0255035, induced a novel object recognition deficit, which was reversed by the M1 agonist, AC260584. Scopolamine fully blocked the effect of clozapine and N-desmethylclozapine, but not lurasidone, to restore novel object recognition in subchronic phencyclidine-treated rats. VU0255035 also blocked these effects of clozapine and N-desmethylclozapine, but not lurasidone; however, the blockade was not as complete as that achieved with scopolamine. Furthermore, subchronic phencyclidine increased hippocampal M1 mRNA expression. These data suggest that M1 agonism is required for clozapine and N-desmethylclozapine to ameliorate the phencyclidine-induced deficit in novel object recognition, additional evidence that M1 agonism is a potential target for treating cognitive impairment in schizophrenia.
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Affiliation(s)
- Masanori Miyauchi
- 1 Department of Psychiatry and Behavioral Sciences, Northwestern Feinberg School of Medicine, Chicago, USA.,2 Sumitomo Dainippon Pharma Co., Ltd, Suita, Japan
| | - Nichole M Neugebauer
- 1 Department of Psychiatry and Behavioral Sciences, Northwestern Feinberg School of Medicine, Chicago, USA
| | - Tatsuya Sato
- 3 Feinberg Cardiovascular Research Institute (FCVRI), Northwestern University Feinberg School of Medicine, Chicago, USA
| | - Hossein Ardehali
- 3 Feinberg Cardiovascular Research Institute (FCVRI), Northwestern University Feinberg School of Medicine, Chicago, USA
| | - Herbert Y Meltzer
- 1 Department of Psychiatry and Behavioral Sciences, Northwestern Feinberg School of Medicine, Chicago, USA
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Bender AM, Weiner RL, Luscombe VB, Ajmera S, Cho HP, Chang S, Zhan X, Rodriguez AL, Niswender CM, Engers DW, Bridges TM, Conn PJ, Lindsley CW. Discovery and optimization of 3-(4-aryl/heteroarylsulfonyl)piperazin-1-yl)-6-(piperidin-1-yl)pyridazines as novel, CNS penetrant pan-muscarinic antagonists. Bioorg Med Chem Lett 2017; 27:3576-3581. [PMID: 28633897 PMCID: PMC6659418 DOI: 10.1016/j.bmcl.2017.05.042] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 05/10/2017] [Accepted: 05/13/2017] [Indexed: 10/19/2022]
Abstract
This letter describes the synthesis and structure activity relationship (SAR) studies of structurally novel M4 antagonists, based on a 3-(4-aryl/heteroarylsulfonyl)piperazin-1-yl)-6-(piperidin-1-yl)pyridazine core, identified from a high-throughput screening campaign. A multi-dimensional optimization effort enhanced potency at human M4 (hM4 IC50s<200nM), with only moderate species differences noted, and with enantioselective inhibition. Moreover, CNS penetration proved attractive for this series (rat brain:plasma Kp=2.1, Kp,uu=1.1). Despite the absence of the prototypical mAChR antagonist basic or quaternary amine moiety, this series displayed pan-muscarinic antagonist activity across M1-5 (with 9- to 16-fold functional selectivity at best). This series further expands the chemical diversity of mAChR antagonists.
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Affiliation(s)
- Aaron M Bender
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Rebecca L Weiner
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Vincent B Luscombe
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Sonia Ajmera
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Hyekyung P Cho
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Sichen Chang
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Xiaoyan Zhan
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Alice L Rodriguez
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Colleen M Niswender
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Vanderbilt Kennedy Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Darren W Engers
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Thomas M Bridges
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - P Jeffrey Conn
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Vanderbilt Kennedy Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Craig W Lindsley
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Chemistry, Vanderbilt University, Nashville, TN 37232, USA.
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45
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Boulos JF, Jakubik J, Boulos JM, Randakova A, Momirov J. Synthesis of novel and functionally selective non-competitive muscarinic antagonists as chemical probes. Chem Biol Drug Des 2017. [PMID: 28646631 DOI: 10.1111/cbdd.13059] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Muscarinic receptors are known to play important biological roles and are drug targets for several human diseases. In a pilot study, novel muscarinic antagonists were synthesized and used as chemical probes to obtain additional information of the muscarinic pharmacophore. The design of these ligands made use of current orthosteric and allosteric models of drug-receptor interactions together with chemical motifs known to achieve muscarinic receptor selectivity. This approach has led to the discovery of several non-competitive muscarinic ligands that strongly bind at a secondary receptor site. These compounds were found to be non-competitive antagonists that completely abolished carbachol activation in functional assays. Several of these compounds antagonized functional response to carbachol with great potency at M1 and M4 than at the rest of receptor subtypes.
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Affiliation(s)
- John F Boulos
- Department of Physical Sciences, Barry University, Miami Shores, FL, USA
| | - Jan Jakubik
- Department of Neurochemistry, Institute of Physiology of the Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - John M Boulos
- Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Alena Randakova
- Department of Neurochemistry, Institute of Physiology of the Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Jelena Momirov
- Department of Physical Sciences, Barry University, Miami Shores, FL, USA
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46
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Radu BM, Osculati AMM, Suku E, Banciu A, Tsenov G, Merigo F, Di Chio M, Banciu DD, Tognoli C, Kacer P, Giorgetti A, Radu M, Bertini G, Fabene PF. All muscarinic acetylcholine receptors (M 1-M 5) are expressed in murine brain microvascular endothelium. Sci Rep 2017; 7:5083. [PMID: 28698560 PMCID: PMC5506046 DOI: 10.1038/s41598-017-05384-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 05/30/2017] [Indexed: 12/25/2022] Open
Abstract
Clinical and experimental studies indicate that muscarinic acetylcholine receptors are potential pharmacological targets for the treatment of neurological diseases. Although these receptors have been described in human, bovine and rat cerebral microvascular tissue, a subtype functional characterization in mouse brain endothelium is lacking. Here, we show that all muscarinic acetylcholine receptors (M1-M5) are expressed in mouse brain microvascular endothelial cells. The mRNA expression of M2, M3, and M5 correlates with their respective protein abundance, but a mismatch exists for M1 and M4 mRNA versus protein levels. Acetylcholine activates calcium transients in brain endothelium via muscarinic, but not nicotinic, receptors. Moreover, although M1 and M3 are the most abundant receptors, only a small fraction of M1 is present in the plasma membrane and functions in ACh-induced Ca2+ signaling. Bioinformatic analyses performed on eukaryotic muscarinic receptors demonstrate a high degree of conservation of the orthosteric binding site and a great variability of the allosteric site. In line with previous studies, this result indicates muscarinic acetylcholine receptors as potential pharmacological targets in future translational studies. We argue that research on drug development should especially focus on the allosteric binding sites of the M1 and M3 receptors.
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Affiliation(s)
- Beatrice Mihaela Radu
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, 37134, Italy.,Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, 050095, Romania
| | | | - Eda Suku
- Department of Biotechnology, University of Verona, Verona, 37134, Italy
| | - Adela Banciu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, 050095, Romania.,Engineering Faculty, Constantin Brancusi' University, Calea Eroilor 30, Targu Jiu, 210135, Romania
| | - Grygoriy Tsenov
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, 37134, Italy
| | - Flavia Merigo
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, 37134, Italy
| | - Marzia Di Chio
- Department of Public Health and Community Medicine, University of Verona, Verona, 37134, Italy
| | - Daniel Dumitru Banciu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, 050095, Romania
| | - Cristina Tognoli
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, 37134, Italy
| | - Petr Kacer
- National Institute of Mental Health, Klecany, 25067, Czech Republic
| | | | - Mihai Radu
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, 37134, Italy. .,Department of Life and Environmental Physics, Horia Hulubei National Institute for Physics and Nuclear Engineering, PO Box MG-6, Reactorului 30, Magurele, 077125, Romania.
| | - Giuseppe Bertini
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, 37134, Italy
| | - Paolo Francesco Fabene
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, 37134, Italy
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47
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Thorn CA, Popiolek M, Stark E, Edgerton JR. Effects of M1 and M4 activation on excitatory synaptic transmission in CA1. Hippocampus 2017; 27:794-810. [PMID: 28422371 PMCID: PMC5573954 DOI: 10.1002/hipo.22732] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 02/24/2017] [Accepted: 03/31/2017] [Indexed: 01/23/2023]
Abstract
Hippocampal networks are particularly susceptible to dysfunction in many neurodegenerative diseases and neuropsychiatric disorders including Alzheimer's disease, Lewy body dementia, and schizophrenia. CA1, a major output region of the hippocampus, receives glutamatergic input from both hippocampal CA3 and entorhinal cortex, via the Schaffer collateral (SC) and temporoammonic (TA) pathways, respectively. SC and TA inputs to CA1 are thought to be differentially involved in the retrieval of previously stored memories versus the encoding of novel information, and switching between these two crucial hippocampal functions is thought to critically depend on acetylcholine (ACh) acting at muscarinic receptors. In this study, we aimed to determine the roles of specific subtypes of muscarinic receptors in mediating the neuromodulatory effects of ACh on glutamatergic synaptic transmission in the SC and TA pathways of CA1. Using selective pharmacological activation of M1 or M4 receptors along with extracellular and intracellular electrophysiology recordings from adult rat hippocampal slices, we demonstrate that activation of M1 receptors increases spontaneous spike rates of neuronal ensembles in CA1 and increases the intrinsic excitability of pyramidal neurons and interneurons. Selective activation of M4 receptors inhibits glutamate release in the SC pathway, while leaving synaptic transmission in the TA pathway comparatively intact. These results suggest specific mechanisms by which M1 and M4 activation may normalize CA1 circuit activity following disruptions of signaling that accompany neurodegenerative dementias or neuropsychiatric disorders. These findings are of particular interest in light of clinical findings that xanomeline, an M1/M4 preferring agonist, was able to improve cognitive and behavioral symptoms in patients with Alzheimer's disease or schizophrenia.
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Affiliation(s)
| | - Michael Popiolek
- Pfizer Internal Medicine Research UnitCambridgeMassachusetts02139
| | - Eda Stark
- Pfizer Internal Medicine Research UnitCambridgeMassachusetts02139
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48
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Hamann M, Plank J, Richter F, Bode C, Smiljanic S, Creed M, Nobrega JN, Richter A. Alterations of M1 and M4 acetylcholine receptors in the genetically dystonic (dt sz) hamster and moderate antidystonic efficacy of M1 and M4 anticholinergics. Neuroscience 2017; 357:84-98. [PMID: 28596119 DOI: 10.1016/j.neuroscience.2017.05.051] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 04/28/2017] [Accepted: 05/29/2017] [Indexed: 11/30/2022]
Abstract
Striatal cholinergic dysfunction has been suggested to play a critical role in the pathophysiology of dystonia. In the dtsz hamster, a phenotypic model of paroxysmal dystonia, M1 antagonists exerted moderate antidystonic efficacy after acute systemic administration. In the present study, we examined the effects of the M4 preferring antagonist tropicamid and whether long-term systemic or acute intrastriatal injections of the M1 preferring antagonist trihexyphenidyl are more effective in mutant hamsters. Furthermore, M1 and M4 receptors were analyzed by autoradiography and immunohistochemistry. Tropicamide retarded the onset of dystonic attacks, as previously observed after acute systemic administration of trihexyphenidyl. Combined systemic administration of trihexyphenidyl (30mg/kg) and tropicamide (15mg/kg) reduced the severity in acute trials and delayed the onset of dystonia during long-term treatment. In contrast, acute striatal microinjections of trihexyphenidyl, tropicamid or the positive allosteric M4 receptor modulator VU0152100 did not exert significant effects. Receptor analyses revealed changes of M1 receptors in the dorsomedial striatum, suggesting that the cholinergic system is involved in abnormal striatal plasticity in dtsz hamsters, but the pharmacological data argue against a crucial role on the phenotype in this animal model. However, antidystonic effects of tropicamide after systemic administration point to a novel therapeutic potential of M4 preferring anticholinergics for the treatment of dystonia.
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Affiliation(s)
- Melanie Hamann
- Institute of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Justus Liebig University Giessen, Schubertstrasse 81, BFS, 35392 Giessen, Germany.
| | - Jagoda Plank
- Institute of Pharmacology and Toxicology, Department of Veterinary Medicine, Freie Universität Berlin, Koserstrasse 20, 14195 Berlin, Germany
| | - Franziska Richter
- Institute of Pharmacology, Pharmacy and Toxicology, Faculty of Veterinary Medicine, University of Leipzig, An den Tierkliniken 15, Leipzig, Germany
| | - Christoph Bode
- Institute of Pharmacology, Pharmacy and Toxicology, Faculty of Veterinary Medicine, University of Leipzig, An den Tierkliniken 15, Leipzig, Germany
| | - Sinisa Smiljanic
- Institute of Pharmacology and Toxicology, Department of Veterinary Medicine, Freie Universität Berlin, Koserstrasse 20, 14195 Berlin, Germany
| | - Meaghan Creed
- Neuroimaging Research Section, Centre for Addiction and Mental Health, Toronto, Canada
| | - José N Nobrega
- Institute of Pharmacology and Toxicology, Department of Veterinary Medicine, Freie Universität Berlin, Koserstrasse 20, 14195 Berlin, Germany
| | - Angelika Richter
- Institute of Pharmacology, Pharmacy and Toxicology, Faculty of Veterinary Medicine, University of Leipzig, An den Tierkliniken 15, Leipzig, Germany.
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49
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Bender AM, Weiner RL, Luscombe VB, Cho HP, Niswender CM, Engers DW, Bridges TM, Conn PJ, Lindsley CW. Synthesis and evaluation of 4,6-disubstituted pyrimidines as CNS penetrant pan-muscarinic antagonists with a novel chemotype. Bioorg Med Chem Lett 2017; 27:2479-2483. [PMID: 28427812 DOI: 10.1016/j.bmcl.2017.04.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 03/28/2017] [Accepted: 04/01/2017] [Indexed: 10/19/2022]
Abstract
This letter describes the synthesis and structure activity relationship (SAR) studies of structurally novel M4 antagonists, based on a 4,6-disubstituted core, identified from a high-throughput screening campaign. A multi-dimensional optimization effort enhanced potency at both human and rat M4 (IC50s<300nM), with no substantial species differences noted. Moreover, CNS penetration proved attractive for this series (brain:plasma Kp,uu=0.87), while other DMPK attributes were addressed in the course of the optimization effort, providing low in vivo clearance in rat (CLp=5.37mL/min/kg). Surprisingly, this series displayed pan-muscarinic antagonist activity across M1-5, despite the absence of the prototypical basic or quaternary amine moiety, thus offering a new chemotype from which to develop a next generation of pan-muscarinic antagonist agents.
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Affiliation(s)
- Aaron M Bender
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Rebecca L Weiner
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Vincent B Luscombe
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Hyekyung P Cho
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Colleen M Niswender
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Vanderbilt Kennedy Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Darren W Engers
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Thomas M Bridges
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - P Jeffrey Conn
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Vanderbilt Kennedy Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Craig W Lindsley
- Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Chemistry, Vanderbilt University, Nashville, TN 37232, USA.
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50
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Soares JI, Valente MC, Andrade PA, Maia GH, Lukoyanov NV. Reorganization of the septohippocampal cholinergic fiber system in experimental epilepsy. J Comp Neurol 2017; 525:2690-2705. [PMID: 28472854 DOI: 10.1002/cne.24235] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 04/11/2017] [Accepted: 04/24/2017] [Indexed: 12/28/2022]
Abstract
The septohippocampal cholinergic neurotransmission has long been implicated in seizures, but little is known about the structural features of this projection system in epileptic brain. We evaluated the effects of experimental epilepsy on the areal density of cholinergic terminals (fiber varicosities) in the dentate gyrus. For this purpose, we used two distinct post-status epilepticus rat models, in which epilepsy was induced with injections of either kainic acid or pilocarpine. To visualize the cholinergic fibers, we used brain sections immunostained for the vesicular acetylcholine transporter. It was found that the density of cholinergic fiber varicosities was higher in epileptic rats versus control rats in the inner and outer zones of the dentate molecular layer, but it was reduced in the dentate hilus. We further evaluated the effects of kainate treatment on the total number, density, and soma volume of septal cholinergic cells, which were visualized in brain sections stained for either vesicular acetylcholine transporter or choline acetyltransferase (ChAT). Both the number of septal cells with cholinergic phenotype and their density were increased in epileptic rats when compared to control rats. The septal cells stained for vesicular acetylcholine transporter, but not for ChAT, have enlarged perikarya in epileptic rats. These results revealed previously unknown details of structural reorganization of the septohippocampal cholinergic system in experimental epilepsy, involving fiber sprouting into the dentate molecular layer and a parallel fiber retraction from the dentate hilus. We hypothesize that epilepsy-related neuroplasticity of septohippocampal cholinergic neurons is capable of increasing neuronal excitability of the dentate gyrus.
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Affiliation(s)
- Joana I Soares
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal.,Neuronal Networks Group, Instituto de Biologia Molecular e Celular da Universidade do Porto, Porto, Portugal.,Departamento de Biologia Experimental, Faculdade de Medicina da Universidade do Porto, Porto, Portugal.,Programa Doutoral em Neurociências, Universidade do Porto, Porto, Portugal
| | - Maria C Valente
- Departamento de Biologia Experimental, Faculdade de Medicina da Universidade do Porto, Porto, Portugal
| | - Pedro A Andrade
- Programa Doutoral em Neurociências, Universidade do Porto, Porto, Portugal.,Department of Neurobiology, A.I. Virtanen Institute, University of Eastern Finland, Kuopio, Finland
| | - Gisela H Maia
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal.,Neuronal Networks Group, Instituto de Biologia Molecular e Celular da Universidade do Porto, Porto, Portugal.,Departamento de Biologia Experimental, Faculdade de Medicina da Universidade do Porto, Porto, Portugal.,Programa Doutoral em Neurociências, Universidade do Porto, Porto, Portugal
| | - Nikolai V Lukoyanov
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal.,Neuronal Networks Group, Instituto de Biologia Molecular e Celular da Universidade do Porto, Porto, Portugal.,Departamento de Anatomia, Faculdade de Medicina da Universidade do Porto, Porto, Portugal
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