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Pu H, Wang Y, Yang T, Leak RK, Stetler RA, Yu F, Zhang W, Shi Y, Hu X, Yin KJ, Hitchens TK, Dixon CE, Bennett MVL, Chen J. Interleukin-4 mitigates anxiety-like behavior and loss of neurons and fiber tracts in limbic structures in a microglial PPARγ-dependent manner after traumatic brain injury. Neurobiol Dis 2023; 180:106078. [PMID: 36914076 DOI: 10.1016/j.nbd.2023.106078] [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: 01/14/2023] [Revised: 03/01/2023] [Accepted: 03/08/2023] [Indexed: 03/13/2023] Open
Abstract
Traumatic brain injury (TBI) is commonly followed by intractable psychiatric disorders and long-term changes in affect, such as anxiety. The present study sought to investigate the effect of repetitive intranasal delivery of interleukin-4 (IL-4) nanoparticles on affective symptoms after TBI in mice. Adult male C57BL/6 J mice (10-12 weeks of age) were subjected to controlled cortical impact (CCI) and assessed by a battery of neurobehavioral tests up to 35 days after CCI. Neuron numbers were counted in multiple limbic structures, and the integrity of limbic white matter tracts was evaluated using ex vivo diffusion tensor imaging (DTI). As STAT6 is a critical mediator of IL-4-specific transcriptional activation, STAT6 knockout mice were used to explore the role of endogenous IL-4/STAT6 signaling axis in TBI-induced affective disorders. We also employed microglia/macrophage (Mi/Mϕ)-specific PPARγ conditional knockout (mKO) mice to test if Mi/Mϕ PPARγ critically contributes to IL-4-afforded beneficial effects. We observed anxiety-like behaviors up to 35 days after CCI, and these measures were exacerbated in STAT6 KO mice but mitigated by repetitive IL-4 delivery. We discovered that IL-4 protected against neuronal loss in limbic structures, such as the hippocampus and the amygdala, and improved the structural integrity of fiber tracts connecting the hippocampus and amygdala. We also observed that IL-4 boosted a beneficial Mi/Mϕ phenotype (CD206+/Arginase 1+/PPARγ+ triple-positive) in the subacute injury phase, and that the numbers of Mi/Mϕ appositions with neurons were robustly correlated with long-term behavioral performances. Remarkably, PPARγ-mKO completely abolished IL-4-afforded protection. Thus, CCI induces long-term anxiety-like behaviors in mice, but these changes in affect can be attenuated by transnasal IL-4 delivery. IL-4 prevents the long-term loss of neuronal somata and fiber tracts in key limbic structures, perhaps due to a shift in Mi/Mϕ phenotype. Exogenous IL-4 therefore holds promise for future clinical management of mood disturbances following TBI.
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Affiliation(s)
- Hongjian Pu
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Yangfan Wang
- Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Tuo Yang
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Rehana K Leak
- Graduate School of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, PA 15282, USA
| | - R Anne Stetler
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Fang Yu
- Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Wenting Zhang
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Yejie Shi
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Xiaoming Hu
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Ke-Jie Yin
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - T Kevin Hitchens
- Animal Imaging Center, University of Pittsburgh School of Medicine, Pittsburgh, PA 15203, USA
| | - C Edward Dixon
- Department of Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Michael V L Bennett
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Jun Chen
- Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15240, USA; Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
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Ancatén-González C, Segura I, Alvarado-Sánchez R, Chávez AE, Latorre R. Ca 2+- and Voltage-Activated K + (BK) Channels in the Nervous System: One Gene, a Myriad of Physiological Functions. Int J Mol Sci 2023; 24:3407. [PMID: 36834817 PMCID: PMC9967218 DOI: 10.3390/ijms24043407] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/18/2023] [Accepted: 01/21/2023] [Indexed: 02/11/2023] Open
Abstract
BK channels are large conductance potassium channels characterized by four pore-forming α subunits, often co-assembled with auxiliary β and γ subunits to regulate Ca2+ sensitivity, voltage dependence and gating properties. BK channels are abundantly expressed throughout the brain and in different compartments within a single neuron, including axons, synaptic terminals, dendritic arbors, and spines. Their activation produces a massive efflux of K+ ions that hyperpolarizes the cellular membrane. Together with their ability to detect changes in intracellular Ca2+ concentration, BK channels control neuronal excitability and synaptic communication through diverse mechanisms. Moreover, increasing evidence indicates that dysfunction of BK channel-mediated effects on neuronal excitability and synaptic function has been implicated in several neurological disorders, including epilepsy, fragile X syndrome, mental retardation, and autism, as well as in motor and cognitive behavior. Here, we discuss current evidence highlighting the physiological importance of this ubiquitous channel in regulating brain function and its role in the pathophysiology of different neurological disorders.
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Affiliation(s)
- Carlos Ancatén-González
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
- Programa de Doctorado en Ciencias, Mención Neurociencia, Universidad de Valparaíso, Valparaíso 2340000, Chile
| | - Ignacio Segura
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
| | - Rosangelina Alvarado-Sánchez
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
- Doctorado en Ciencias Mención Biofísica y Biología Computacional, Universidad de Valparaíso, Valparaíso 2340000, Chile
| | - Andrés E. Chávez
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
| | - Ramon Latorre
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
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Andrews PL, Williams RS, Sanger GJ. Anti-emetic effects of thalidomide: Evidence, mechanism of action, and future directions. CURRENT RESEARCH IN PHARMACOLOGY AND DRUG DISCOVERY 2022; 3:100138. [PMID: 36568268 PMCID: PMC9780081 DOI: 10.1016/j.crphar.2022.100138] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 10/10/2022] [Accepted: 10/26/2022] [Indexed: 11/06/2022] Open
Abstract
The rationale for using thalidomide (THD) as a treatment for nausea and vomiting during pregnancy in the late 1950s appears to have been based on its sedative or hypnotic properties. In contrast to contemporaneous studies on the anti-emetic activity of phenothiazines, we were unable to identify publications reporting preclinical or clinical evaluation of THD as an anti-emetic. Our survey of the literature revealed a clinical study in 1965 showing THD reduced vomiting in cancer chemotherapy which was substantiated by similar studies from 2000, particularly showing efficacy in the delayed phase of chemotherapy-induced nausea and vomiting. To identify the mechanism(s) potentially involved in thalidomide's anti-emetic activity we reviewed its pharmacology in the light of nausea and vomiting mechanisms and their pharmacology with a particular emphasis on chemotherapy and pregnancy. The process identified the following potential mechanisms: reduced secretion of Growth Differentiation Factor 15, suppression of inflammation/prostaglandin production, downregulation of cytotoxic drug induced upregulation of iNOS, and modulation of BK (KCa1.1) channels and GABAA/glutamate transmission at critical points in the emetic pathways (nucleus tractus solitarius, area postrema). We propose ways to investigate these hypothesized mechanisms and discuss the associated challenges (e.g., objective quantification of nausea) in addition to some of the more general aspects of developing novel drugs to treat nausea and vomiting.
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Affiliation(s)
- Paul L.R. Andrews
- Division of Biomedical Sciences, St George's University of London, London, United Kingdom
| | - Robin S.B. Williams
- Centre for Biomedical Sciences, Department of Biological Sciences, Royal Holloway University of London, Egham, United Kingdom
| | - Gareth J. Sanger
- Blizard Institute, Faculty of Medicine and Dentistry, Queen Mary University of London, United Kingdom
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Saltarella I, Altamura C, Lamanuzzi A, Apollonio B, Vacca A, Frassanito MA, Desaphy JF. Ion Channels in Multiple Myeloma: Pathogenic Role and Therapeutic Perspectives. Int J Mol Sci 2022; 23:ijms23137302. [PMID: 35806308 PMCID: PMC9266328 DOI: 10.3390/ijms23137302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 06/27/2022] [Accepted: 06/27/2022] [Indexed: 12/10/2022] Open
Abstract
Ion channels are pore-forming proteins that allow ions to flow across plasma membranes and intracellular organelles in both excitable and non-excitable cells. They are involved in the regulation of several biological processes (i.e., proliferation, cell volume and shape, differentiation, migration, and apoptosis). Recently, the aberrant expression of ion channels has emerged as an important step of malignant transformation, tumor progression, and drug resistance, leading to the idea of “onco-channelopathy”. Here, we review the contribution of ion channels and transporters in multiple myeloma (MM), a hematological neoplasia characterized by the expansion of tumor plasma cells (MM cells) in the bone marrow (BM). Deregulation of ion channels sustains MM progression by modulating intracellular pathways that promote MM cells’ survival, proliferation, and drug resistance. Finally, we focus on the promising role of ion channels as therapeutic targets for the treatment of MM patients in a combination strategy with currently used anti-MM drugs to improve their cytotoxic activity and reduce adverse effects.
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Affiliation(s)
- Ilaria Saltarella
- Department of Biomedical Sciences and Human Oncology, Section of Pharmacology, University of Bari Aldo Moro Medical School, Piazza Giulio Cesare 11, I-70124 Bari, Italy
| | - Concetta Altamura
- Department of Biomedical Sciences and Human Oncology, Section of Pharmacology, University of Bari Aldo Moro Medical School, Piazza Giulio Cesare 11, I-70124 Bari, Italy
| | - Aurelia Lamanuzzi
- Department of Biomedical Sciences and Human Oncology, Section of Internal Medicine, University of Bari Aldo Moro Medical School, I-70124 Bari, Italy
| | - Benedetta Apollonio
- Department of Biomedical Sciences and Human Oncology, Section of Internal Medicine, University of Bari Aldo Moro Medical School, I-70124 Bari, Italy
| | - Angelo Vacca
- Department of Biomedical Sciences and Human Oncology, Section of Internal Medicine, University of Bari Aldo Moro Medical School, I-70124 Bari, Italy
| | - Maria Antonia Frassanito
- Department of Biomedical Sciences and Human Oncology, Section of General Pathology, University of Bari Aldo Moro Medical School, I-70124 Bari, Italy
| | - Jean-François Desaphy
- Department of Biomedical Sciences and Human Oncology, Section of Pharmacology, University of Bari Aldo Moro Medical School, Piazza Giulio Cesare 11, I-70124 Bari, Italy
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Activating BK channels ameliorates vascular smooth muscle calcification through Akt signaling. Acta Pharmacol Sin 2022; 43:624-633. [PMID: 34163023 PMCID: PMC8888620 DOI: 10.1038/s41401-021-00704-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 05/23/2021] [Indexed: 02/06/2023] Open
Abstract
Vascular calcification (VC) is characterized by pathological depositions of calcium and phosphate in the arteries and veins via an active cell-regulated process, in which vascular smooth muscle cells (VSMCs) transform into osteoblast/chondrocyte-like cells as in bone formation. VC is associated with significant morbidity and mortality in chronic kidney disease (CKD) and cardiovascular disease, but the underlying mechanisms remain unclear. In this study we investigated the role of large-conductance calcium-activated potassium (BK) channels in 3 experimental VC models. VC was induced in vascular smooth muscle cells (VSMCs) by β-glycerophosphate (β-GP), or in rats by subtotal nephrectomy, or in mice by high-dosage vitamin D3. We showed that the expression of BK channels in the artery of CKD rats with VC and in β-GP-treated VSMCs was significantly decreased, which was functionally confirmed by patch-clamp recording. In β-GP-treated VSMCs, BK channel opener NS1619 (20 μM) significantly alleviated VC by decreasing calcium content and alkaline phosphatase activity. Furthermore, NS1619 decreased mRNA expression of ostoegenic genes OCN and OPN, as well as Runx2 (a key transcription factor involved in preosteoblast to osteoblast differentiation), and increased the expression of α-SMA protein, whereas BK channel inhibitor paxilline (10 μM) caused the opposite effects. In primary cultured VSMCs from BK-/- mice, BK deficiency aggravated calcification as did BK channel inhibitor in normal VSMCs. Moreover, calcification was more severe in thoracic aorta rings of BK-/- mice than in those of wild-type littermates. Administration of BK channel activator BMS191011 (10 mg· kg-1 ·d-1) in high-dosage vitamin D3-treated mice significantly ameliorated calcification. Finally, co-treatment with Akt inhibitor MK2206 (1 μM) or FoxO1 inhibitor AS1842856 (3 μM) in calcified VSMCs abrogated the effects of BK channel opener NS1619. Taken together, activation of BK channels ameliorates VC via Akt/FoxO1 signaling pathways. Strategies to activate BK channels and/or enhance BK channel expression may offer therapeutic avenues to control VC.
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Miller JP, Moldenhauer HJ, Keros S, Meredith AL. An emerging spectrum of variants and clinical features in KCNMA1-linked channelopathy. Channels (Austin) 2021; 15:447-464. [PMID: 34224328 PMCID: PMC8259716 DOI: 10.1080/19336950.2021.1938852] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
KCNMA1-linked channelopathy is an emerging neurological disorder characterized by heterogeneous and overlapping combinations of movement disorder, seizure, developmental delay, and intellectual disability. KCNMA1 encodes the BK K+ channel, which contributes to both excitatory and inhibitory neuronal and muscle activity. Understanding the basis of the disorder is an important area of active investigation; however, the rare prevalence has hampered the development of large patient cohorts necessary to establish genotype-phenotype correlations. In this review, we summarize 37 KCNMA1 alleles from 69 patients currently defining the channelopathy and assess key diagnostic and clinical hallmarks. At present, 3 variants are classified as gain-of-function with respect to BK channel activity, 14 loss-of-function, 15 variants of uncertain significance, and putative benign/VUS. Symptoms associated with these variants were curated from patient-provided information and prior publications to define the spectrum of clinical phenotypes. In this newly expanded cohort, seizures showed no differential distribution between patients harboring GOF and LOF variants, while movement disorders segregated by mutation type. Paroxysmal non-kinesigenic dyskinesia was predominantly observed among patients with GOF alleles of the BK channel, although not exclusively so, while additional movement disorders were observed in patients with LOF variants. Neurodevelopmental and structural brain abnormalities were prevalent in patients with LOF mutations. In contrast to mutations, disease-associated KCNMA1 single nucleotide polymorphisms were not predominantly related to neurological phenotypes but covered a wider set of peripheral physiological functions. Together, this review provides additional evidence exploring the genetic and biochemical basis for KCNMA1-linked channelopathy and summarizes the clinical repository of patient symptoms across multiple types of KCNMA1 gene variants.
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Affiliation(s)
- Jacob P Miller
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Hans J Moldenhauer
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Sotirios Keros
- Department of Pediatrics, Weill Cornell Medical College, New York, NY, USA
| | - Andrea L Meredith
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
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Fan F, Chen Y, Chen Z, Guan L, Ye Z, Tang Y, Chen A, Lin C. Blockade of BK channels attenuates chronic visceral hypersensitivity in an IBS-like rat model. Mol Pain 2021; 17:17448069211040364. [PMID: 34407673 PMCID: PMC8381452 DOI: 10.1177/17448069211040364] [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: 05/04/2021] [Revised: 07/08/2021] [Accepted: 07/31/2021] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Visceral hypersensitivity in irritable bowel syndrome (IBS) is still poorly understood, despite that chronic abdominal pain is the most common symptoms in IBS patients. To study effects of BK channels on visceral hypersensitivity in IBS rats and the underlying mechanisms, IBS rats were established by colorectal distention (CRD) in postnatal rats. The expression of large-conductance calcium and voltage-dependent potassium ion channels (BK channels) of the thoracolumbar spinal cord was examined in IBS and control rats. The effects of BK channel blockade on visceral hypersensitivity were evaluated. The interaction of BK channels and N-methyl-D-aspartate acid (NMDA) receptors was explored, and synaptic transmission at superficial dorsal horn (SDH) neurons of the thoracolumbar spinal cord was recorded by whole-cell patch clamp in IBS rats. RESULTS The expression of the BK channels of the thoracolumbar spinal cord in IBS rats was significantly reduced. The blockade of BK channels could reduce the visceral hypersensitivity in IBS rats. There was an interaction between BK channels and NMDA receptors in the spinal cord. The frequency of spontaneous inhibitory postsynaptic currents (sIPSCs) in SDH neurons is significantly reduced in IBS rats. The blockade of BK channels depolarizes the inhibitory interneuron membrane and increases their excitability in IBS rats. CONCLUSIONS BK channels could interact with NMDA receptors in the thoracolumbar spinal cord of rats and regulate visceral hypersensitivity in IBS rats.
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Affiliation(s)
- F Fan
- Nursing Department, Fujian Health College, China
- School of basic Medical Sciences, Laboratory of Pain Research,
Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases,
Fujian Medical University, China
| | - Y Chen
- School of basic Medical Sciences, Laboratory of Pain Research,
Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases,
Fujian Medical University, China
| | - Z Chen
- School of basic Medical Sciences, Laboratory of Pain Research,
Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases,
Fujian Medical University, China
| | - L Guan
- School of basic Medical Sciences, Laboratory of Pain Research,
Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases,
Fujian Medical University, China
| | - Z Ye
- School of basic Medical Sciences, Laboratory of Pain Research,
Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases,
Fujian Medical University, China
| | - Y Tang
- School of basic Medical Sciences, Laboratory of Pain Research,
Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases,
Fujian Medical University, China
| | - A Chen
- School of basic Medical Sciences, Laboratory of Pain Research,
Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases,
Fujian Medical University, China
| | - C Lin
- School of basic Medical Sciences, Laboratory of Pain Research,
Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases,
Fujian Medical University, China
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Hypnotic effect of thalidomide is independent of teratogenic ubiquitin/proteasome pathway. Proc Natl Acad Sci U S A 2020; 117:23106-23112. [PMID: 32848052 DOI: 10.1073/pnas.1917701117] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Thalidomide exerts its teratogenic and immunomodulatory effects by binding to cereblon (CRBN) and thereby inhibiting/modifying the CRBN-mediated ubiquitination pathway consisting of the Cullin4-DDB1-ROC1 E3 ligase complex. The mechanism of thalidomide's classical hypnotic effect remains largely unexplored, however. Here we examined whether CRBN is involved in the hypnotic effect of thalidomide by generating mice harboring a thalidomide-resistant mutant allele of Crbn (Crbn YW/AA knock-in mice). Thalidomide increased non-REM sleep time in Crbn YW/AA knock-in homozygotes and heterozygotes to a similar degree as seen in wild-type littermates. Thalidomide similarly depressed excitatory synaptic transmission in the cortical slices obtained from wild-type and Crbn YW/AA homozygous knock-in mice without affecting GABAergic inhibition. Thalidomide induced Fos expression in vasopressin-containing neurons of the supraoptic nucleus and reduced Fos expression in the tuberomammillary nuclei. Thus, thalidomide's hypnotic effect seems to share some downstream mechanisms with general anesthetics and GABAA-activating sedatives but does not involve the teratogenic CRBN-mediated ubiquitin/proteasome pathway.
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