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Masuoka T, Kiyoi T, Zheng S, He Q, Liu L, Uwada J, Muramatsu I. Corneal acetylcholine regulates sensory nerve activity via nicotinic receptors. Ocul Surf 2024; 32:60-70. [PMID: 38242319 DOI: 10.1016/j.jtos.2024.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 12/19/2023] [Accepted: 01/16/2024] [Indexed: 01/21/2024]
Abstract
PURPOSE Sensory nerve terminals are highly distributed in the cornea, and regulate ocular surface sensation and homeostasis in response to various endogenous and exogenous stimuli. However, little is known about mediators regulating the physiological and pathophysiological activities of corneal sensory nerves. The aim of this study was to investigate the presence of cholinergic regulation in sensory nerves in the cornea. METHODS Localization of choline acetyltransferase (ChAT) and vesicular acetylcholine transporter (vAChT) was evaluated using western blotting and immunohistochemical analysis. The synthesis and liberation of acetylcholine from the cornea were assessed using corneal segments pre-incubated with [3H]choline. The responsiveness of corneal neurons and nerves to cholinergic drugs was explored using calcium imaging with primary cultures of trigeminal ganglion neurons and extracellular recording from corneal preparations in guinea pigs. RESULTS ChAT, but not vAChT, was highly distributed in the corneal epithelium. In corneal segments, [3H] acetylcholine was synthesized from [3H]choline, and was also released in response to electrical stimuli. In cultured corneal neurons, the population sensitive to a transient receptor potential melastatin 8 (TRPM8) agonist exhibited high probability of responding to nicotine in a calcium imaging experiment. The firing frequency of cold-sensitive corneal nerves was increased by the application of nicotine, but diminished by an α4 nicotinic acetylcholine receptor antagonist. CONCLUSIONS The corneal epithelium can synthesize and release acetylcholine. Corneal acetylcholine can excite sensory nerves via nicotinic receptors containing the α4 subunit. Therefore, corneal acetylcholine may be one of the important regulators of corneal nerve activity arranging ocular surface condition and sensation.
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Affiliation(s)
- Takayoshi Masuoka
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa, 920-0293, Japan.
| | - Takeshi Kiyoi
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa, 920-0293, Japan
| | - Shijie Zheng
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa, 920-0293, Japan
| | - Qiang He
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa, 920-0293, Japan
| | - Li Liu
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa, 920-0293, Japan
| | - Junsuke Uwada
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa, 920-0293, Japan
| | - Ikunobu Muramatsu
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa, 920-0293, Japan; Division of Genomic Science and Microbiology, School of Medicine, University of Fukui, Eiheiji, Fukui, 910-1193, Japan
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Wang Y, Sun Y, Wang Y, Jia S, Qiao Y, Zhou Z, Shao W, Zhang X, Guo J, Song X, Niu X, Peng D. Urine metabolomics phenotyping and urinary biomarker exploratory in mild cognitive impairment and Alzheimer's disease. Front Aging Neurosci 2023; 15:1273807. [PMID: 38187356 PMCID: PMC10768723 DOI: 10.3389/fnagi.2023.1273807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 09/20/2023] [Indexed: 01/09/2024] Open
Abstract
Introduction Alzheimer's disease is a prevalent disease with a heavy global burden and is suggested to be a metabolic disease in the brain in recent years. The metabolome is considered to be the most promising phenotype which reflects changes in genetic, transcript, and protein profiles as well as environmental effects. Aiming to obtain a comprehensive understanding and convenient diagnosis of MCI and AD from another perspective, researchers are working on AD metabolomics. Urine is more convenient which could reflect the change of disease at an earlier stage. Thus, we conducted a cross-sectional study to investigate novel diagnostic panels. Methods We first enrolled participants from China-Japan Friendship Hospital from April 2022 to November 2022, collected urine samples and conducted an LC-MS/MS analysis. In parallel, clinical data were collected and clinical examinations were performed. After statistical and bioinformatics analyzes, significant risk factors and differential urinary metabolites were determined. We attempt to investigate diagnostic panels based on machine learning including LASSO and SVM. Results Fifty-seven AD patients, 43 MCI patients and 62 CN subjects were enrolled. A total of 2,140 metabolites were identified among which 125 significantly differed between the AD and CN groups, including 46 upregulated ones and 79 downregulated ones. In parallel, there were 93 significant differential metabolites between the MCI and CN groups, including 23 upregulated ones and 70 downregulated ones. AD diagnostic panel (30 metabolites+ age + APOE) achieved an AUC of 0.9575 in the test set while MCI diagnostic panel (45 metabolites+ age + APOE) achieved an AUC of 0.7333 in the test set. Atropine, S-Methyl-L-cysteine-S-oxide, D-Mannose 6-phosphate (M6P), Spiculisporic Acid, N-Acetyl-L-methionine, 13,14-dihydro-15-keto-tetranor Prostaglandin D2, Pyridoxal 5'-Phosphate (PLP) and 17(S)-HpDHA were considered valuable for both AD and MCI diagnosis and defined as hub metabolites. Besides, diagnostic metabolites were weakly correlated with cognitive functions. Discussion In conclusion, the procedure is convenient, non-invasive, and useful for diagnosis, which could assist physicians in differentiating AD and MCI from CN. Atropine, M6P and PLP were evidence-based hub metabolites in AD.
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Affiliation(s)
- Yuye Wang
- China-Japan Friendship Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- Department of Neurology, China-Japan Friendship Hospital, Beijing, China
| | - Yu Sun
- Department of Neurology, China-Japan Friendship Hospital, Beijing, China
| | - Yu Wang
- Department of Neurology, China-Japan Friendship Hospital, Beijing, China
| | - Shuhong Jia
- Department of Neurology, China-Japan Friendship Hospital, Beijing, China
| | - Yanan Qiao
- Department of Neurology, China-Japan Friendship Hospital, Beijing, China
| | - Zhi Zhou
- Department of Neurology, China-Japan Friendship Hospital, Beijing, China
| | - Wen Shao
- Department of Neurology, China-Japan Friendship Hospital, Beijing, China
| | - Xiangfei Zhang
- Department of Neurology, China-Japan Friendship Hospital, Beijing, China
| | - Jing Guo
- Department of Neurology, China-Japan Friendship Hospital, Beijing, China
| | - Xincheng Song
- Department of Neurology, China-Japan Friendship Hospital, Beijing, China
- Peking University China-Japan Friendship School of Clinical Medicine, Beijing, China
| | - Xiaoqian Niu
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
| | - Dantao Peng
- China-Japan Friendship Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- Department of Neurology, China-Japan Friendship Hospital, Beijing, China
- Peking University China-Japan Friendship School of Clinical Medicine, Beijing, China
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Arakawa I, Muramatsu I, Uwada J, Sada K, Matsukawa N, Masuoka T. Acetylcholine release from striatal cholinergic interneurons is controlled differently depending on the firing pattern. J Neurochem 2023; 167:38-51. [PMID: 37653723 DOI: 10.1111/jnc.15950] [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: 02/18/2023] [Revised: 07/31/2023] [Accepted: 08/11/2023] [Indexed: 09/02/2023]
Abstract
How is the quantal size in neurotransmitter release adjusted for various firing levels? We explored the possible mechanisms that regulate acetylcholine (ACh) release from cholinergic interneurons using an ultra-mini superfusion system. After preloading [3 H]ACh in rat striatal cholinergic interneurons, the release was elicited by electrical stimulation under a condition in which presynaptic cholinergic and dopaminergic feedback was inhibited. [3 H]ACh release was reproducible at intervals of more than 10 min; shorter intervals resulted in reduced levels of ACh release. Upon persistent stimulation for 10 min, ACh release transiently increased, before gradually decreasing. Vesamicol, an inhibitor of the vesicular ACh transporter (VAChT), had no effect on the release induced by the first single pulse, but it reduced the release caused by subsequent pulses. Vesamicol also reduced the [3 H]ACh release evoked by multiple pulses, and the inhibition was enhanced by repetitive stimulation. The decreasing phase of [3 H]ACh release during persistent stimulation was accelerated by vesamicol treatment. Thus, it is likely that releasable ACh was slowly compensated for via VAChT during and after stimulation, changing the vesicular ACh content. In addition, ACh release per pulse decreased under high-frequency stimulation. The present results suggest that ACh release from striatal cholinergic interneurons may be adjusted by changes in the quantal size due to slow replenishment via VAChT, and by a reduction in release probability upon high-frequency stimulation. These two distinct processes likely enable the fine tuning of neurotransmission and neuroprotection/limitation against excessive output and have important physiological roles in the brain.
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Affiliation(s)
- Itsumi Arakawa
- Department of Neurology, Nagoya City University Graduate School of Medicine, Nagoya, Japan
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, Uchinada, Japan
- Division of Genomic Science and Microbiology, School of Medicine, University of Fukui, Fukui, Japan
| | - Ikunobu Muramatsu
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, Uchinada, Japan
- Division of Genomic Science and Microbiology, School of Medicine, University of Fukui, Fukui, Japan
- Kimura Hospital, Fukui, Japan
| | - Junsuke Uwada
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, Uchinada, Japan
| | - Kiyonao Sada
- Division of Genomic Science and Microbiology, School of Medicine, University of Fukui, Fukui, Japan
| | - Noriyuki Matsukawa
- Department of Neurology, Nagoya City University Graduate School of Medicine, Nagoya, Japan
| | - Takayoshi Masuoka
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, Uchinada, Japan
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Antal B, McMahon LP, Sultan SF, Lithen A, Wexler DJ, Dickerson B, Ratai EM, Mujica-Parodi LR. Type 2 diabetes mellitus accelerates brain aging and cognitive decline: Complementary findings from UK Biobank and meta-analyses. eLife 2022; 11:73138. [PMID: 35608247 PMCID: PMC9132576 DOI: 10.7554/elife.73138] [Citation(s) in RCA: 60] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 04/26/2022] [Indexed: 01/17/2023] Open
Abstract
Background Type 2 diabetes mellitus (T2DM) is known to be associated with neurobiological and cognitive deficits; however, their extent, overlap with aging effects, and the effectiveness of existing treatments in the context of the brain are currently unknown. Methods We characterized neurocognitive effects independently associated with T2DM and age in a large cohort of human subjects from the UK Biobank with cross-sectional neuroimaging and cognitive data. We then proceeded to evaluate the extent of overlap between the effects related to T2DM and age by applying correlation measures to the separately characterized neurocognitive changes. Our findings were complemented by meta-analyses of published reports with cognitive or neuroimaging measures for T2DM and healthy controls (HCs). We also evaluated in a cohort of T2DM-diagnosed individuals using UK Biobank how disease chronicity and metformin treatment interact with the identified neurocognitive effects. Results The UK Biobank dataset included cognitive and neuroimaging data (N = 20,314), including 1012 T2DM and 19,302 HCs, aged between 50 and 80 years. Duration of T2DM ranged from 0 to 31 years (mean 8.5 ± 6.1 years); 498 were treated with metformin alone, while 352 were unmedicated. Our meta-analysis evaluated 34 cognitive studies (N = 22,231) and 60 neuroimaging studies: 30 of T2DM (N = 866) and 30 of aging (N = 1088). Compared to age, sex, education, and hypertension-matched HC, T2DM was associated with marked cognitive deficits, particularly in executive functioning and processing speed. Likewise, we found that the diagnosis of T2DM was significantly associated with gray matter atrophy, primarily within the ventral striatum, cerebellum, and putamen, with reorganization of brain activity (decreased in the caudate and premotor cortex and increased in the subgenual area, orbitofrontal cortex, brainstem, and posterior cingulate cortex). The structural and functional changes associated with T2DM show marked overlap with the effects correlating with age but appear earlier, with disease duration linked to more severe neurodegeneration. Metformin treatment status was not associated with improved neurocognitive outcomes. Conclusions The neurocognitive impact of T2DM suggests marked acceleration of normal brain aging. T2DM gray matter atrophy occurred approximately 26% ± 14% faster than seen with normal aging; disease duration was associated with increased neurodegeneration. Mechanistically, our results suggest a neurometabolic component to brain aging. Clinically, neuroimaging-based biomarkers may provide a valuable adjunctive measure of T2DM progression and treatment efficacy based on neurological effects. Funding The research described in this article was funded by the W. M. Keck Foundation (to LRMP), the White House Brain Research Through Advancing Innovative Technologies (BRAIN) Initiative (NSFNCS-FR 1926781 to LRMP), and the Baszucki Brain Research Fund (to LRMP). None of the funding sources played any role in the design of the experiments, data collection, analysis, interpretation of the results, the decision to publish, or any aspect relevant to the study. DJW reports serving on data monitoring committees for Novo Nordisk. None of the authors received funding or in-kind support from pharmaceutical and/or other companies to write this article.
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Affiliation(s)
- Botond Antal
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, United States.,Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, United States
| | - Liam P McMahon
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, United States.,Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, United States
| | - Syed Fahad Sultan
- Department of Computer Science, Stony Brook University, Stony Brook, United States
| | - Andrew Lithen
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, United States.,Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, United States
| | - Deborah J Wexler
- Diabetes Center, Massachusetts General Hospital and Harvard Medical School, Boston, United States
| | - Bradford Dickerson
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, United States.,Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, United States
| | - Eva-Maria Ratai
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, United States
| | - Lilianne R Mujica-Parodi
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, United States.,Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, United States.,Department of Neurology, Stony Brook University School of Medicine, Stony Brook, United States
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5
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Pradhan LK, Sahoo PK, Chauhan S, Das SK. Recent Advances Towards Diagnosis and Therapeutic Fingerprinting for Alzheimer's Disease. J Mol Neurosci 2022; 72:1143-1165. [PMID: 35553375 DOI: 10.1007/s12031-022-02009-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 04/02/2022] [Indexed: 12/12/2022]
Abstract
Since the report of "a peculiar severe disease process of the cerebral cortex" by Alois Alzheimer in 1906, it was considered to be a rare condition characterized by loss of cognition, memory impairment, and pathological markers such as senile plaques or neurofibrillary tangles (NFTs). Later on, the report was published in the textbook "Psychiatrie" and the disease was named as Alzheimer's disease (AD) and was known to be the consequences of aging; however, owing to its complex etiology, there is no cure for the progressive neurodegenerative disorder. Our current understanding of the mechanisms involved in the pathogenesis of AD is still at the mechanistic level. The treatment strategies applied currently only alleviate the symptoms and co-morbidities. For instance, the available treatments such as the usage of acetylcholinesterase inhibitors and N-methyl D-aspartate antagonists have minimal impact on the disease progression and target the later aspects of the disease. The recent advancements in the last two decades have made us more clearly understand the pathophysiology of the disease which has led to the development of novel therapeutic strategies. This review gives a brief idea about the various facets of AD pathophysiology and its management through modern investigational therapies to give a new direction for development of targeted therapeutic measures.
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Affiliation(s)
- Lilesh Kumar Pradhan
- Neurobiology Laboratory, Centre for Biotechnology, Siksha 'O' Anusandhan (Deemed to Be University), Kalinga Nagar, Bhubaneswar-751003, India
| | - Pradyumna Kumar Sahoo
- Neurobiology Laboratory, Centre for Biotechnology, Siksha 'O' Anusandhan (Deemed to Be University), Kalinga Nagar, Bhubaneswar-751003, India
| | - Santosh Chauhan
- Autophagy Laboratory, Infectious Disease Biology Division, Institute of Life Sciences, Bhubaneswar-751023, India.
| | - Saroj Kumar Das
- Neurobiology Laboratory, Centre for Biotechnology, Siksha 'O' Anusandhan (Deemed to Be University), Kalinga Nagar, Bhubaneswar-751003, India.
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Kato D, Suto T, Obata H, Saito S. The efficacy of duloxetine depends on spinal cholinergic plasticity in neuropathic pain model rats. IBRO Neurosci Rep 2022; 12:188-196. [PMID: 35243478 PMCID: PMC8881419 DOI: 10.1016/j.ibneur.2022.02.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 02/10/2022] [Indexed: 12/25/2022] Open
Abstract
Antidepressants, such as duloxetine, are widely used to treat chronic pain, including neuropathic pain; however, their efficacy is unsatisfactory. In our previous studies, we showed that in a spinal nerve ligation (SNL) rat model, the descending noradrenergic inhibitory system, which involves in the anti-hypersensitivity mechanism of antidepressants, decrease its activity over time following peripheral nerve injury. In this study, we hypothesized that the analgesic effects of duloxetine may diminish following the attenuation of the descending noradrenergic inhibitory system. The analgesic effects of duloxetine in SNL model rats at the early (SNL2W) and chronic (SNL6W) phases following spinal nerve ligation were compared. Male Sprague-Dawley rats were randomly assigned to the SNL2W or SNL6W groups and used to evaluate the anti-allodynic effects of duloxetine using the von Frey filament test. The anti-allodynic effects of duloxetine at a dose of 10 mg/kg were lower in SNL6W rats than in SNL2W rats. Basal noradrenaline concentrations in rat spinal dorsal horns were higher in the SNL6W group than in the SNL2W group, and there was no difference in the increase in spinal noradrenaline concentrations between the 2 groups following duloxetine administration. In addition, we found that duloxetine-induced acetylcholine (ACh) release and choline acetyltransferase (ChAT) expression in the spinal dorsal horn decreased in SNL6W rats. At a dose of 30 mg/kg, duloxetine showed anti-allodynic effects even in SNL6W rats and induced ACh release in the spinal cord. Furthermore, these anti-allodynic effects were completely inhibited by intrathecal atropine (muscarinic antagonist) administration. Moreover, 5 daily intraperitoneal injections of the TrkB agonist, 7,8-dihydroxyflavone (5 mg/kg), not only restored ChAT expression, but also decreased the anti-allodynic effects of duloxetine. These findings suggest that the attenuation of the anti-allodynic effects of duloxetine at the chronic phase of SNL may be due to impaired spinal acetylcholine-mediated analgesia. In addition, the activation of BDNF-TrkB signaling may be beneficial in reversing this impairment. The anti-allodynic effect of duloxetine decreases at chronic stage following nerve injury than at early phase. There are no differences in the inhibition of noradrenaline reuptake by duloxetine between SNL2W and SNL6W rats. The spinal ChAT immunoreactivity and duloxetine-induced spinal ACh release are reduced in SNL6W rats. TrkB agonist increases spinal ChAT and restores the attenuation of anti-allodynic effects of duloxetine in SNL6W rats.
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Affiliation(s)
- Daiki Kato
- Department of Anesthesiology, Gunma University Graduate School of Medicine, 3-39-22 Showa, Maebashi, Gunma 371-8511, Japan
| | - Takashi Suto
- Department of Anesthesiology, Gunma University Graduate School of Medicine, 3-39-22 Showa, Maebashi, Gunma 371-8511, Japan
- Correspondence to: Department of Anesthesiology, Gunma University Graduate School of Medicine, #1, 3-39-22 Showa-machi, Maebashi-shi, Gunma 371-8511, Japan.
| | - Hideaki Obata
- Department of Anesthesiology, Saitama Medical Center, Saitama Medical University, 1981 Kamoda, Kawagoe, Saitama 350-8550, Japan
| | - Shigeru Saito
- Department of Anesthesiology, Gunma University Graduate School of Medicine, 3-39-22 Showa, Maebashi, Gunma 371-8511, Japan
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Muramatsu I, Uwada J, Chihara K, Sada K, Wang MH, Yazawa T, Taniguchi T, Ishibashi T, Masuoka T. Evaluation of radiolabeled acetylcholine synthesis and release in rat striatum. J Neurochem 2021; 160:342-355. [PMID: 34878648 DOI: 10.1111/jnc.15556] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 10/18/2021] [Accepted: 11/30/2021] [Indexed: 12/26/2022]
Abstract
Cholinergic transmission underlies higher brain functions such as cognition and movement. To elucidate the process whereby acetylcholine (ACh) release is maintained and regulated in the central nervous system, uptake of [3 H]choline and subsequent synthesis and release of [3 H]ACh were investigated in rat striatal segments. Incubation with [3 H]choline elicited efficient uptake via high-affinity choline transporter-1, resulting in accumulation of [3 H]choline and [3 H]ACh. However, following inhibition of ACh esterase (AChE), incubation with [3 H]choline led predominantly to the accumulation of [3 H]ACh. Electrical stimulation and KCl depolarization selectively released [3 H]ACh but not [3 H]choline. [3 H]ACh release gradually declined upon repetitive stimulation, whereas the release was reproducible under inhibition of AChE. [3 H]ACh release was abolished after treatment with vesamicol, an inhibitor of vesicular ACh transporter. These results suggest that releasable ACh is continually replenished from the cytosol to releasable pools of cholinergic vesicles to maintain cholinergic transmission. [3 H]ACh release evoked by electrical stimulation was abolished by tetrodotoxin, but that induced by KCl was largely resistant. ACh release was Ca2+ dependent and exhibited slightly different sensitivities to N- and P-type Ca2+ channel toxins (ω-conotoxin GVIA and ω-agatoxin IVA, respectively) between both stimuli. [3 H]ACh release was negatively regulated by M2 muscarinic and D2 dopaminergic receptors. The present results suggest that inhibition of AChE within cholinergic neurons and of presynaptic negative regulation of ACh release contributes to maintenance and facilitation of cholinergic transmission, providing a potentially useful clue for the development of therapies for cholinergic dysfunction-associated disorders, in addition to inhibition of synaptic cleft AChE.
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Affiliation(s)
- Ikunobu Muramatsu
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, Uchinada, Ishikawa, Japan.,Division of Genomic Science and Microbiology, School of Medicine, University of Fukui, Eiheiji, Fukui, Japan.,Kimura Hospital, Awara, Fukui, Japan
| | - Junsuke Uwada
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, Uchinada, Ishikawa, Japan.,Division of Cellular Signal Transduction, Department of Biochemistry, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Kazuyasu Chihara
- Division of Genomic Science and Microbiology, School of Medicine, University of Fukui, Eiheiji, Fukui, Japan
| | - Kiyonao Sada
- Division of Genomic Science and Microbiology, School of Medicine, University of Fukui, Eiheiji, Fukui, Japan
| | - Mao-Hsien Wang
- Division of Genomic Science and Microbiology, School of Medicine, University of Fukui, Eiheiji, Fukui, Japan.,Department of Anesthesia, En Chu Kon Hospital, New Taipei City, Taiwan, ROC
| | - Takashi Yazawa
- Division of Cellular Signal Transduction, Department of Biochemistry, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Takanobu Taniguchi
- Division of Cellular Signal Transduction, Department of Biochemistry, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Takaharu Ishibashi
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, Uchinada, Ishikawa, Japan
| | - Takayoshi Masuoka
- Department of Pharmacology, School of Medicine, Kanazawa Medical University, Uchinada, Ishikawa, Japan
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Li M, Huang C, Wu X, Ding F, Hu Z, Zhu Y, Zhao L, Hou L, Chen H, Wang H, Xu J, Tang D. The optimization of a novel selective antagonist for human M 2 muscarinic acetylcholine receptor. Bioorg Med Chem Lett 2020; 30:127632. [PMID: 33132116 DOI: 10.1016/j.bmcl.2020.127632] [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: 07/31/2020] [Revised: 10/14/2020] [Accepted: 10/16/2020] [Indexed: 01/22/2023]
Abstract
Muscarinic acetylcholine receptors (mAChRs) comprise five distinct subtypes denoted M1 to M5. The antagonism of M2 subtype could increase the release of acetylcholine from vesicles into the synaptic cleft and improve postsynaptic functions in the hippocampus via M1 receptor activation, displaying therapeutic potentials for Alzheimer's disease. However, drug development for M2 antagonists is still challenged among different receptor subtypes. In this study, by optimizing a scaffold from virtual screening, we synthesized two focused libraries and generated up to 50 derivatives. By measuring potency and binding selectivity, we discovered a novel M2 antagonist, ligand 47, featuring submicromolar IC50, high M2/M4 selectivity (~30-fold) and suitable lipophilicity (cLogP = 4.55). Further study with these compounds also illustrates the structure-activity relationship of this novel scaffold. Our study could not only provide novel lead structure, which was easy to synthesize, but also offer valuable information for further development of selective M2 ligands.
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Affiliation(s)
- Miaomiao Li
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Chen Huang
- Department of Nuclear Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pu Jian Road, Shanghai 200127, China; College of Medical Imaging, Shanghai University of Medicine and Health Sciences, Shanghai 201318, China
| | - Xingyu Wu
- College of Pharmacy, Shanghai University of Medicine and Health Sciences, Shanghai 201318, China
| | - Fan Ding
- Department of Nuclear Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pu Jian Road, Shanghai 200127, China
| | - Zhoumi Hu
- Department of Nuclear Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pu Jian Road, Shanghai 200127, China
| | - Yan Zhu
- School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Lanxue Zhao
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Lina Hou
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Hongzhuan Chen
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China; Institute of Interdisciplinary Integrative Biomedical Research, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Hao Wang
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Jianrong Xu
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China; Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China.
| | - Dewei Tang
- Department of Nuclear Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pu Jian Road, Shanghai 200127, China.
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9
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Jin G, Li Z, Xiao F, Qi X, Sun X. Optimization of activity localization of quinoline derivatives: Design, synthesis, and dual evaluation of biological activity for potential antitumor and antibacterial agents. Bioorg Chem 2020; 99:103837. [DOI: 10.1016/j.bioorg.2020.103837] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 12/25/2019] [Accepted: 04/06/2020] [Indexed: 02/08/2023]
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