1
|
Cheng S, Jiang D, Lan X, Liu K, Fan C. Voltage-gated potassium channel 1.3: A promising molecular target in multiple disease therapy. Biomed Pharmacother 2024; 175:116651. [PMID: 38692062 DOI: 10.1016/j.biopha.2024.116651] [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: 02/20/2024] [Revised: 04/21/2024] [Accepted: 04/24/2024] [Indexed: 05/03/2024] Open
Abstract
Voltage-gated potassium channel 1.3 (Kv1.3) has emerged as a pivotal player in numerous biological processes and pathological conditions, sparking considerable interest as a potential therapeutic target across various diseases. In this review, we present a comprehensive examination of Kv1.3 channels, highlighting their fundamental characteristics and recent advancements in utilizing Kv1.3 inhibitors for treating autoimmune disorders, neuroinflammation, and cancers. Notably, Kv1.3 is prominently expressed in immune cells and implicated in immune responses and inflammation associated with autoimmune diseases and chronic inflammatory conditions. Moreover, its aberrant expression in certain tumors underscores its role in cancer progression. While preclinical studies have demonstrated the efficacy of Kv1.3 inhibitors, their clinical translation remains pending. Molecular imaging techniques offer promising avenues for tracking Kv1.3 inhibitors and assessing their therapeutic efficacy, thereby facilitating their development and clinical application. Challenges and future directions in Kv1.3 inhibitor research are also discussed, emphasizing the significant potential of targeting Kv1.3 as a promising therapeutic strategy across a spectrum of diseases.
Collapse
Affiliation(s)
- Sixuan Cheng
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; Hubei Key Laboratory of Molecular Imaging, Wuhan 430022, China
| | - Dawei Jiang
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; Hubei Key Laboratory of Molecular Imaging, Wuhan 430022, China
| | - Xiaoli Lan
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; Hubei Key Laboratory of Molecular Imaging, Wuhan 430022, China
| | - Kun Liu
- Department of Cardiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
| | - Cheng Fan
- Department of Geriatrics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
| |
Collapse
|
2
|
Lee JM, Kim J, Park SJ, Nam JH, Kim HJ, Kim WK. Regulation of T Lymphocyte Functions through Calcium Signaling Modulation by Nootkatone. Int J Mol Sci 2024; 25:5240. [PMID: 38791278 PMCID: PMC11121628 DOI: 10.3390/ijms25105240] [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: 04/03/2024] [Revised: 05/02/2024] [Accepted: 05/06/2024] [Indexed: 05/26/2024] Open
Abstract
Recent advancements in understanding the intricate molecular mechanisms underlying immunological responses have underscored the critical involvement of ion channels in regulating calcium influx, particularly in inflammation. Nootkatone, a natural sesquiterpenoid found in Alpinia oxyphylla and various citrus species, has gained attention for its diverse pharmacological properties, including anti-inflammatory effects. This study aimed to elucidate the potential of nootkatone in modulating ion channels associated with calcium signaling, particularly CRAC, KV1.3, and KCa3.1 channels, which play pivotal roles in immune cell activation and proliferation. Using electrophysiological techniques, we demonstrated the inhibitory effects of nootkatone on CRAC, KV1.3, and KCa3.1 channels in HEK293T cells overexpressing respective channel proteins. Nootkatone exhibited dose-dependent inhibition of channel currents, with IC50 values determined for each channel. Nootkatone treatment did not significantly affect cell viability, indicating its potential safety for therapeutic applications. Furthermore, we observed that nootkatone treatment attenuated calcium influx through activated CRAC channels and showed anti-proliferative effects, suggesting its role in regulating inflammatory T cell activation. These findings highlight the potential of nootkatone as a natural compound for modulating calcium signaling pathways by targeting related key ion channels and it holds promise as a novel therapeutic agent for inflammatory disorders.
Collapse
Affiliation(s)
- Ji Min Lee
- Department of Physiology, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Gyeongsangbuk-do, Republic of Korea; (J.M.L.); (S.J.P.); (J.H.N.)
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, 32 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea;
| | - Jintae Kim
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, 32 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea;
| | - Su Jin Park
- Department of Physiology, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Gyeongsangbuk-do, Republic of Korea; (J.M.L.); (S.J.P.); (J.H.N.)
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, 32 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea;
| | - Joo Hyun Nam
- Department of Physiology, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Gyeongsangbuk-do, Republic of Korea; (J.M.L.); (S.J.P.); (J.H.N.)
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, 32 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea;
| | - Hyun Jong Kim
- Department of Physiology, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Gyeongsangbuk-do, Republic of Korea; (J.M.L.); (S.J.P.); (J.H.N.)
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, 32 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea;
| | - Woo Kyung Kim
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, 32 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea;
- Department of Internal Medicine, Graduate School of Medicine, Dongguk University, 27 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea
| |
Collapse
|
3
|
Hey G, Rao R, Carter A, Reddy A, Valle D, Patel A, Patel D, Lucke-Wold B, Pomeranz Krummel D, Sengupta S. Ligand-Gated Ion Channels: Prognostic and Therapeutic Implications for Gliomas. J Pers Med 2023; 13:jpm13050853. [PMID: 37241023 DOI: 10.3390/jpm13050853] [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: 04/20/2023] [Revised: 05/05/2023] [Accepted: 05/17/2023] [Indexed: 05/28/2023] Open
Abstract
Gliomas are common primary brain malignancies that remain difficult to treat due to their overall aggressiveness and heterogeneity. Although a variety of therapeutic strategies have been employed for the treatment of gliomas, there is increasing evidence that suggests ligand-gated ion channels (LGICs) can serve as a valuable biomarker and diagnostic tool in the pathogenesis of gliomas. Various LGICs, including P2X, SYT16, and PANX2, have the potential to become altered in the pathogenesis of glioma, which can disrupt the homeostatic activity of neurons, microglia, and astrocytes, further exacerbating the symptoms and progression of glioma. Consequently, LGICs, including purinoceptors, glutamate-gated receptors, and Cys-loop receptors, have been targeted in clinical trials for their potential therapeutic benefit in the diagnosis and treatment of gliomas. In this review, we discuss the role of LGICs in the pathogenesis of glioma, including genetic factors and the effect of altered LGIC activity on the biological functioning of neuronal cells. Additionally, we discuss current and emerging investigations regarding the use of LGICs as a clinical target and potential therapeutic for gliomas.
Collapse
Affiliation(s)
- Grace Hey
- College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Rohan Rao
- College of Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Ashley Carter
- Eastern Virginia Medical School, Norfolk, VA 23507, USA
| | - Akshay Reddy
- College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Daisy Valle
- College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Anjali Patel
- College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Drashti Patel
- College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Brandon Lucke-Wold
- Department of Neurosurgery, University of Florida, Gainesville, FL 23608, USA
| | - Daniel Pomeranz Krummel
- Department of Neurology & Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Soma Sengupta
- Department of Neurology & Rehabilitation Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| |
Collapse
|
4
|
Chun BJ, Aryal SP, Varughese P, Sun B, Bruno JA, Richards CI, Bachstetter AD, Kekenes-Huskey PM. Purinoreceptors and ectonucleotidases control ATP-induced calcium waveforms and calcium-dependent responses in microglia: Roles of P2 receptors and CD39 in ATP-stimulated microglia. Front Physiol 2023; 13:1037417. [PMID: 36699679 PMCID: PMC9868579 DOI: 10.3389/fphys.2022.1037417] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 12/12/2022] [Indexed: 01/11/2023] Open
Abstract
Adenosine triphosphate (ATP) and its metabolites drive microglia migration and cytokine production by activating P2X- and P2Y- class purinergic receptors. Purinergic receptor activation gives rise to diverse intracellular calcium (Ca2+ signals, or waveforms, that differ in amplitude, duration, and frequency. Whether and how these characteristics of diverse waveforms influence microglia function is not well-established. We developed a computational model trained with data from published primary murine microglia studies. We simulate how purinoreceptors influence Ca2+ signaling and migration, as well as, how purinoreceptor expression modifies these processes. Our simulation confirmed that P2 receptors encode the amplitude and duration of the ATP-induced Ca2+ waveforms. Our simulations also implicate CD39, an ectonucleotidase that rapidly degrades ATP, as a regulator of purinergic receptor-induced Ca2+ responses. Namely, it was necessary to account for CD39 metabolism of ATP to align the model's predicted purinoreceptor responses with published experimental data. In addition, our modeling results indicate that small Ca2+ transients accompany migration, while large and sustained transients are needed for cytokine responses. Lastly, as a proof-of-principal, we predict Ca2+ transients and cell membrane displacements in a BV2 microglia cell line using published P2 receptor mRNA data to illustrate how our computer model may be extrapolated to other microglia subtypes. These findings provide important insights into how differences in purinergic receptor expression influence microglial responses to ATP.
Collapse
Affiliation(s)
- Byeong J. Chun
- Department of Cell and Molecular Physiology, Loyola University Chicago, Chicago, IL, United States,*Correspondence: Byeong J. Chun, ; Peter M. Kekenes-Huskey,
| | - Surya P. Aryal
- Department of Chemistry, University of Kentucky, Lexington, KY, United States
| | - Peter Varughese
- Department of Cell and Molecular Physiology, Loyola University Chicago, Chicago, IL, United States
| | - Bin Sun
- Department of Cell and Molecular Physiology, Loyola University Chicago, Chicago, IL, United States
| | - Joshua A. Bruno
- Department of Physics, Loyola University Chicago, Chicago, IL, United States
| | - Chris I. Richards
- Department of Chemistry, University of Kentucky, Lexington, KY, United States
| | | | - Peter M. Kekenes-Huskey
- Department of Cell and Molecular Physiology, Loyola University Chicago, Chicago, IL, United States,*Correspondence: Byeong J. Chun, ; Peter M. Kekenes-Huskey,
| |
Collapse
|
5
|
Kim J, Jeon SG, Jeong HR, Park H, Kim JI, Hoe HS. L-Type Ca 2+ Channel Inhibition Rescues the LPS-Induced Neuroinflammatory Response and Impairments in Spatial Memory and Dendritic Spine Formation. Int J Mol Sci 2022; 23:13606. [PMID: 36362394 PMCID: PMC9655622 DOI: 10.3390/ijms232113606] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 10/26/2022] [Accepted: 11/03/2022] [Indexed: 08/11/2023] Open
Abstract
Ca2+ signaling is implicated in the transition between microglial surveillance and activation. Several L-type Ca2+ channel blockers (CCBs) have been shown to ameliorate neuroinflammation by modulating microglial activity. In this study, we examined the effects of the L-type CCB felodipine on LPS-mediated proinflammatory responses. We found that felodipine treatment significantly diminished LPS-evoked proinflammatory cytokine levels in BV2 microglial cells in an L-type Ca2+ channel-dependent manner. In addition, felodipine leads to the inhibition of TLR4/AKT/STAT3 signaling in BV2 microglial cells. We further examined the effects of felodipine on LPS-stimulated neuroinflammation in vivo and found that daily administration (3 or 7 days, i.p.) significantly reduced LPS-mediated gliosis and COX-2 and IL-1β levels in C57BL/6 (wild-type) mice. Moreover, felodipine administration significantly reduced chronic neuroinflammation-induced spatial memory impairment, dendritic spine number, and microgliosis in C57BL/6 mice. Taken together, our results suggest that the L-type CCB felodipine could be repurposed for the treatment of neuroinflammation/cognitive function-associated diseases.
Collapse
Affiliation(s)
- Jieun Kim
- Department of Neural Development and Disease, Korea Brain Research Institute (KBRI), 61, Cheomdan-ro, Dong-gu, Daegu 41062, Korea
| | - Seong Gak Jeon
- Department of Neural Development and Disease, Korea Brain Research Institute (KBRI), 61, Cheomdan-ro, Dong-gu, Daegu 41062, Korea
| | - Ha-Ram Jeong
- Department of Neural Development and Disease, Korea Brain Research Institute (KBRI), 61, Cheomdan-ro, Dong-gu, Daegu 41062, Korea
| | - HyunHee Park
- Department of Neural Development and Disease, Korea Brain Research Institute (KBRI), 61, Cheomdan-ro, Dong-gu, Daegu 41062, Korea
| | - Jae-Ick Kim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea
| | - Hyang-Sook Hoe
- Department of Neural Development and Disease, Korea Brain Research Institute (KBRI), 61, Cheomdan-ro, Dong-gu, Daegu 41062, Korea
- Department of Brain and Cognitive Science, Daegu Gyeongbuk Institute of Science & Technology (DGIST), 333, Techno Jungang-Daero, Hyeonpung-eup, Dalseong-gun, Daegu 42988, Korea
| |
Collapse
|
6
|
Revuelta M, Urrutia J, Villarroel A, Casis O. Microglia-Mediated Inflammation and Neural Stem Cell Differentiation in Alzheimer's Disease: Possible Therapeutic Role of K V1.3 Channel Blockade. Front Cell Neurosci 2022; 16:868842. [PMID: 35530176 PMCID: PMC9070300 DOI: 10.3389/fncel.2022.868842] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 03/31/2022] [Indexed: 12/14/2022] Open
Abstract
Increase of deposits of amyloid β peptides in the extracellular matrix is landmark during Alzheimer’s Disease (AD) due to the imbalance in the production vs. clearance. This accumulation of amyloid β deposits triggers microglial activation. Microglia plays a dual role in AD, a protective role by clearing the deposits of amyloid β peptides increasing the phagocytic response (CD163, IGF-1 or BDNF) and a cytotoxic role, releasing free radicals (ROS or NO) and proinflammatory cytokines (TNF-α, IL-1β) in response to reactive gliosis activated by the amyloid β aggregates. Microglia activation correlated with an increase KV1.3 channels expression, protein levels and current density. Several studies highlight the importance of KV1.3 in the activation of inflammatory response and inhibition of neural progenitor cell proliferation and neuronal differentiation. However, little is known about the pathways of this activation in neural stem cells differentiation and proliferation and the role in amyloid β accumulation. In recent studies using in vitro cells derived from mice models, it has been demonstrated that KV1.3 blockers inhibit microglia-mediated neurotoxicity in culture reducing the expression and production of the pro-inflammatory cytokines IL-1β and TNF-α through the NF-kB and p38MAPK pathway. Overall, we conclude that KV1.3 blockers change the course of AD development, reducing microglial cytotoxic activation and increasing neural stem cell differentiation. However, further investigations are needed to establish the specific pathway and to validate the use of this blocker as therapeutic treatment in Alzheimer patients.
Collapse
Affiliation(s)
- Miren Revuelta
- Department of Physiology, Faculty of Medicine and Nursery, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Janire Urrutia
- Department of Physiology, Faculty of Medicine and Nursery, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Alvaro Villarroel
- Instituto Biofisika, Consejo Superior de Investigaciones Científicas (CSIC)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Leioa, Spain
| | - Oscar Casis
- Department of Physiology, Faculty of Pharmacy, University of the Basque Country (UPV/EHU), Vitoria-Gasteiz, Spain
| |
Collapse
|
7
|
You Y, Muraoka S, Jedrychowski MP, Hu J, McQuade AK, Young‐Pearse T, Aslebagh R, Shaffer SA, Gygi SP, Blurton‐Jones M, Poon WW, Ikezu T. Human neural cell type-specific extracellular vesicle proteome defines disease-related molecules associated with activated astrocytes in Alzheimer's disease brain. J Extracell Vesicles 2022; 11:e12183. [PMID: 35029059 PMCID: PMC8758831 DOI: 10.1002/jev2.12183] [Citation(s) in RCA: 54] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 12/10/2021] [Indexed: 12/30/2022] Open
Abstract
In neurodegenerative diseases, extracellular vesicles (EVs) transfer pathogenic molecules and are consequently involved in disease progression. We have investigated the proteomic profiles of EVs that were isolated from four different human-induced pluripotent stem cell-derived neural cell types (excitatory neurons, astrocytes, microglia-like cells, and oligodendrocyte-like cells). Novel cell type-specific EV protein markers were then identified for the excitatory neurons (ATP1A3, NCAM1), astrocytes (LRP1, ITGA6), microglia-like cells (ITGAM, LCP1), and oligodendrocyte-like cells (LAMP2, FTH1), as well as 16 pan-EV marker candidates, including integrins and annexins. To further demonstrate how cell-type-specific EVs may be involved in Alzheimer's disease (AD), we performed protein co-expression network analysis and conducted cell type assessments for the proteomes of brain-derived EVs from the control, mild cognitive impairment, and AD cases. A protein module enriched in astrocyte-specific EV markers was most significantly associated with the AD pathology and cognitive impairment, suggesting an important role in AD progression. The hub protein from this module, integrin-β1 (ITGB1), was found to be significantly elevated in astrocyte-specific EVs enriched from the total brain-derived AD EVs and associated with the brain β-amyloid and tau load in independent cohorts. Thus, our study provides a featured framework and rich resource for the future analyses of EV functions in neurodegenerative diseases in a cell type-specific manner.
Collapse
Affiliation(s)
- Yang You
- Department of Pharmacology & Experimental TherapeuticsBoston University School of MedicineBostonMassachusettsUSA
- Department of NeuroscienceMayo Clinic FloridaJacksonvilleFloridaUSA
| | - Satoshi Muraoka
- Department of Pharmacology & Experimental TherapeuticsBoston University School of MedicineBostonMassachusettsUSA
| | | | - Jianqiao Hu
- Department of Pharmacology & Experimental TherapeuticsBoston University School of MedicineBostonMassachusettsUSA
| | - Amanda K. McQuade
- Department of Neurobiology and Behavior, Institute for Memory Impairments and Neurological DisordersUniversity of CaliforniaIrvineCaliforniaUSA
| | - Tracy Young‐Pearse
- Department of Neurology, Brigham and Women's HospitalHarvard Medical SchoolBostonMassachusettsUSA
| | - Roshanak Aslebagh
- Department of Biochemistry and Molecular PharmacologyUniversity of Massachusetts Medical SchoolWorcesterMassachusettsUSA
- Mass Spectrometry FacilityUniversity of Massachusetts Medical SchoolShrewsburyMassachusettsUSA
| | - Scott A. Shaffer
- Department of Biochemistry and Molecular PharmacologyUniversity of Massachusetts Medical SchoolWorcesterMassachusettsUSA
- Mass Spectrometry FacilityUniversity of Massachusetts Medical SchoolShrewsburyMassachusettsUSA
| | - Steven P. Gygi
- Department of Cell BiologyHarvard Medical SchoolBostonMassachusettsUSA
| | - Mathew Blurton‐Jones
- Department of Neurobiology and Behavior, Institute for Memory Impairments and Neurological DisordersUniversity of CaliforniaIrvineCaliforniaUSA
| | - Wayne W. Poon
- Department of Neurobiology and Behavior, Institute for Memory Impairments and Neurological DisordersUniversity of CaliforniaIrvineCaliforniaUSA
| | - Tsuneya Ikezu
- Department of Pharmacology & Experimental TherapeuticsBoston University School of MedicineBostonMassachusettsUSA
- Department of NeuroscienceMayo Clinic FloridaJacksonvilleFloridaUSA
- The Robert and Arlene Kogod Center on AgingMayo ClinicRochesterMinnesotaUSA
| |
Collapse
|
8
|
da Silva JF, Binda NS, Pereira EMR, de Lavor MSL, Vieira LB, de Souza AH, Rigo FK, Ferrer HT, de Castro CJ, Ferreira J, Gomez MV. Analgesic effects of Phα1β toxin: a review of mechanisms of action involving pain pathways. J Venom Anim Toxins Incl Trop Dis 2021; 27:e20210001. [PMID: 34868281 PMCID: PMC8610172 DOI: 10.1590/1678-9199-jvatitd-2021-0001] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Accepted: 03/26/2021] [Indexed: 01/01/2023] Open
Abstract
Phα1β is a neurotoxin purified from spider venom that acts as a high-voltage-activated (HVA) calcium channel blocker. This spider peptide has shown a high selectivity for N-type HVA calcium channels (NVACC) and an analgesic effect in several animal models of pain. Its activity was associated with a reduction in calcium transients, glutamate release, and reactive oxygen species production from the spinal cord tissue and dorsal ganglia root (DRG) in rats and mice. It has been reported that intrathecal (i.t.) administration of Phα1β to treat chronic pain reverted opioid tolerance with a safer profile than ω-conotoxin MVIIA, a highly selective NVACC blocker. Following a recent development of recombinant Phα1β (CTK 01512-2), a new molecular target, TRPA1, the structural arrangement of disulphide bridges, and an effect on glial plasticity have been identified. CTK 01512-2 reproduced the antinociceptive effects of the native toxin not only after the intrathecal but also after the intravenous administration. Herein, we review the Phα1β antinociceptive activity in the most relevant pain models and its mechanisms of action, highlighting the impact of CTK 01512-2 synthesis and its potential for multimodal analgesia.
Collapse
Affiliation(s)
- Juliana Figueira da Silva
- Laboratory of Pharmacology, Department of Pharmacy, Federal
University of Ouro Preto, Ouro Preto, MG, Brazil
| | - Nancy Scardua Binda
- Laboratory of Pharmacology, Department of Pharmacy, Federal
University of Ouro Preto, Ouro Preto, MG, Brazil
| | - Elizete Maria Rita Pereira
- Graduate Program in Health Sciences, Institute of Education and
Research, Santa Casa de Belo Horizonte, Belo Horizonte, MG, Brazil
| | | | - Luciene Bruno Vieira
- Department of Pharmacology, Institute of Biological Sciences (ICB),
Federal University of Minas Gerais (UFMG), Belo Horizonte, MG, Brazil
| | - Alessandra Hubner de Souza
- Graduate Program in Health Sciences, Institute of Education and
Research, Santa Casa de Belo Horizonte, Belo Horizonte, MG, Brazil
| | - Flávia Karine Rigo
- Graduate Program in Health Sciences, University of the Extreme South
of Santa Catarina (UNESC), Criciúma, SC, Brazil
| | - Hèlia Tenza Ferrer
- Center of Technology in Molecular Medicine, School of Medicine,
Federal University of Minas Gerais (UFMG), Belo Horizonte, MG, Brazil
| | - Célio José de Castro
- Graduate Program in Health Sciences, Institute of Education and
Research, Santa Casa de Belo Horizonte, Belo Horizonte, MG, Brazil
| | - Juliano Ferreira
- Department of Pharmacology, Federal University of Santa Catarina,
Florianópolis, SC, Brazil
| | - Marcus Vinicius Gomez
- Graduate Program in Health Sciences, Institute of Education and
Research, Santa Casa de Belo Horizonte, Belo Horizonte, MG, Brazil
- Center of Technology in Molecular Medicine, School of Medicine,
Federal University of Minas Gerais (UFMG), Belo Horizonte, MG, Brazil
| |
Collapse
|
9
|
Metcalf CS, Vanegas F, Underwood T, Johnson K, West PJ, Smith MD, Wilcox KS. Screening of prototype antiseizure and anti-inflammatory compounds in the Theiler's murine encephalomyelitis virus model of epilepsy. Epilepsia Open 2021; 7:46-58. [PMID: 34668659 PMCID: PMC8886069 DOI: 10.1002/epi4.12550] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 10/10/2021] [Accepted: 10/12/2021] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVE Infection with Theiler's murine encephalomyelitis virus (TMEV) in C57Bl/6J mice results in handling-induced seizures and is useful for evaluating compounds effective against infection-induced seizures. However, to date only a few compounds have been evaluated in this model, and a comprehensive study of antiseizure medications (ASMs) has not yet been performed. Furthermore, as the TMEV infection produces marked neuroinflammation, an evaluation of prototype anti-inflammatory compounds is needed as well. METHODS Male C57Bl/6J mice were inoculated with TMEV (day 0) followed by daily administrations of test compounds (day 3-7) and subsequent handling sessions (day 3-7). Doses of ASMs, comprising several mechanistic classes, were selected based on previously published data demonstrating the effect of these compounds in reducing seizures in the 6 Hz model of pharmacoresistant seizures. Doses of anti-inflammatory compounds, comprising several mechanistic classes, were selected based on published evidence of reduction of inflammation or inflammation-related endpoints. RESULTS Several prototype ASMs reduced acute seizures following TMEV infection: lacosamide, phenytoin, ezogabine, phenobarbital, tiagabine, gabapentin, levetiracetam, topiramate, and sodium valproate. Of these, phenobarbital and sodium valproate had the greatest effect (>95% seizure burden reduction). Prototype anti-inflammatory drugs celecoxib, dexamethasone, and prednisone also moderately reduced seizure burden. SIGNIFICANCE The TMEV model is utilized by the Epilepsy Therapy Screening Program (ETSP) as a tool for evaluation of novel compounds. Compounds reducing seizures in the TMEV comprise distinct mechanistic classes, some with mechanisms of action that extend beyond traditional ASMs.
Collapse
Affiliation(s)
- Cameron S Metcalf
- Epilepsy Therapy Screening Program Contract Site, Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, Utah, USA
| | - Fabiola Vanegas
- Epilepsy Therapy Screening Program Contract Site, Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, Utah, USA
| | - Tristan Underwood
- Epilepsy Therapy Screening Program Contract Site, Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, Utah, USA
| | - Kristina Johnson
- Epilepsy Therapy Screening Program Contract Site, Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, Utah, USA
| | - Peter J West
- Epilepsy Therapy Screening Program Contract Site, Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, Utah, USA
| | - Misty D Smith
- Epilepsy Therapy Screening Program Contract Site, Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, Utah, USA.,School of Dentistry, University of Utah, Salt Lake City, Utah, USA
| | - Karen S Wilcox
- Epilepsy Therapy Screening Program Contract Site, Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, Utah, USA
| |
Collapse
|
10
|
Ion Channels as New Attractive Targets to Improve Re-Myelination Processes in the Brain. Int J Mol Sci 2021; 22:ijms22147277. [PMID: 34298893 PMCID: PMC8305962 DOI: 10.3390/ijms22147277] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 06/28/2021] [Accepted: 07/01/2021] [Indexed: 12/20/2022] Open
Abstract
Multiple sclerosis (MS) is the most demyelinating disease of the central nervous system (CNS) characterized by neuroinflammation. Oligodendrocyte progenitor cells (OPCs) are cycling cells in the developing and adult CNS that, under demyelinating conditions, migrate to the site of lesions and differentiate into mature oligodendrocytes to remyelinate damaged axons. However, this process fails during disease chronicization due to impaired OPC differentiation. Moreover, OPCs are crucial players in neuro-glial communication as they receive synaptic inputs from neurons and express ion channels and neurotransmitter/neuromodulator receptors that control their maturation. Ion channels are recognized as attractive therapeutic targets, and indeed ligand-gated and voltage-gated channels can both be found among the top five pharmaceutical target groups of FDA-approved agents. Their modulation ameliorates some of the symptoms of MS and improves the outcome of related animal models. However, the exact mechanism of action of ion-channel targeting compounds is often still unclear due to the wide expression of these channels on neurons, glia, and infiltrating immune cells. The present review summarizes recent findings in the field to get further insights into physio-pathophysiological processes and possible therapeutic mechanisms of drug actions.
Collapse
|
11
|
Song B, Lee SJ, Kim CH. Roles of Cytokines in the Temporal Changes of Microglial Membrane Currents and Neuronal Excitability and Synaptic Efficacy in ATP-Induced Cortical Injury Model. Int J Mol Sci 2021; 22:ijms22136853. [PMID: 34202215 PMCID: PMC8268462 DOI: 10.3390/ijms22136853] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/18/2021] [Accepted: 06/23/2021] [Indexed: 12/20/2022] Open
Abstract
Cytokines are important neuroinflammatory modulators in neurodegenerative brain disorders including traumatic brain injury (TBI) and stroke. However, their temporal effects on the physiological properties of microglia and neurons during the recovery period have been unclear. Here, using an ATP-induced cortical injury model, we characterized selective effects of ATP injection compared to needle-control. In the damaged region, the fluorescent intensity of CX3CR1-GFP (+) cells, as well as the cell density, was increased and the maturation of newborn BrdU (+) cells continued until 28 day-post-injection (dpi) of ATP. The excitability and synaptic E/I balance of neurons and the inward and outward membrane currents of microglia were increased at 3 dpi, when expressions of tumor necrosis factor (TNF)-α/interleukin (IL)-1β and IL-10/IL-4 were also enhanced. These changes of both cells at 3 dpi were mostly decayed at 7 dpi and were suppressed by any of IL-10, IL-4, suramin (P2 receptor inhibitor) and 4-AP (K+ channel blocker). Acute ATP application alone induced only small effects from both naïve neurons and microglial cells in brain slice. However, TNF-α alone effectively increased the excitability of naïve neurons, which was blocked by suramin or 4-AP. TNF-α and IL-1β increased and decreased membrane currents of naïve microglia, respectively. Our results suggest that ATP and TNF-α dominantly induce the physiological activities of 3 dpi neurons and microglia, and IL-10 effectively suppresses such changes of both activated cells in K+ channel- and P2 receptor-dependent manner, while IL-4 suppresses neurons preferentially.
Collapse
Affiliation(s)
- Bokyung Song
- Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea;
- Neuroscience Program, Division of Bio-Medical Science and Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Korea
| | - Sung-Joong Lee
- Program in Neuroscience, Dental Research Institute, School of Dentistry, Seoul National University, Seoul 08826, Korea;
| | - Chong-Hyun Kim
- Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea;
- Neuroscience Program, Division of Bio-Medical Science and Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Korea
- Correspondence:
| |
Collapse
|
12
|
Kim K, Wang X, Ragonnaud E, Bodogai M, Illouz T, DeLuca M, McDevitt RA, Gusev F, Okun E, Rogaev E, Biragyn A. Therapeutic B-cell depletion reverses progression of Alzheimer's disease. Nat Commun 2021; 12:2185. [PMID: 33846335 PMCID: PMC8042032 DOI: 10.1038/s41467-021-22479-4] [Citation(s) in RCA: 82] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 03/12/2021] [Indexed: 01/16/2023] Open
Abstract
The function of B cells in Alzheimer's disease (AD) is not fully understood. While immunoglobulins that target amyloid beta (Aβ) may interfere with plaque formation and hence progression of the disease, B cells may contribute beyond merely producing immunoglobulins. Here we show that AD is associated with accumulation of activated B cells in circulation, and with infiltration of B cells into the brain parenchyma, resulting in immunoglobulin deposits around Aβ plaques. Using three different murine transgenic models, we provide counterintuitive evidence that the AD progression requires B cells. Despite expression of the AD-fostering transgenes, the loss of B cells alone is sufficient to reduce Aβ plaque burden and disease-associated microglia. It reverses behavioral and memory deficits and restores TGFβ+ microglia, respectively. Moreover, therapeutic depletion of B cells at the onset of the disease retards AD progression in mice, suggesting that targeting B cells may also benefit AD patients.
Collapse
Affiliation(s)
- Ki Kim
- Immunoregulation Section, Laboratory of Immunology and Molecular Biology, National Institute on Aging, Baltimore, MD, USA
| | - Xin Wang
- Immunoregulation Section, Laboratory of Immunology and Molecular Biology, National Institute on Aging, Baltimore, MD, USA
| | - Emeline Ragonnaud
- Immunoregulation Section, Laboratory of Immunology and Molecular Biology, National Institute on Aging, Baltimore, MD, USA
| | - Monica Bodogai
- Immunoregulation Section, Laboratory of Immunology and Molecular Biology, National Institute on Aging, Baltimore, MD, USA
| | - Tomer Illouz
- The Mina and Everard Goodman faculty of Life Sciences, Ramat Gan, Israel
- The Gonda Brain Research Center, Bar Ilan University, Ramat Gan, Israel
- The Paul Feder Laboratory on Alzheimer's disease research, Bar Ilan University, Ramat Gan, Israel
| | - Marisa DeLuca
- Immunoregulation Section, Laboratory of Immunology and Molecular Biology, National Institute on Aging, Baltimore, MD, USA
| | - Ross A McDevitt
- Mouse Phenotyping Unit, Comparative Medicine Section, National Institute on Aging, Baltimore, MD, USA
| | - Fedor Gusev
- Department of Genomics and Human Genetics, Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia
| | - Eitan Okun
- The Mina and Everard Goodman faculty of Life Sciences, Ramat Gan, Israel
- The Gonda Brain Research Center, Bar Ilan University, Ramat Gan, Israel
- The Paul Feder Laboratory on Alzheimer's disease research, Bar Ilan University, Ramat Gan, Israel
| | - Evgeny Rogaev
- Department of Genomics and Human Genetics, Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia
- Center for Genetics and Genetic Technologies, Faculty of Biology, Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia
- Department of Psychiatry, University of Massachusetts Medical School, Worcester, MA, USA
- Sirius University of Science and Technology, Sochi, Russia
| | - Arya Biragyn
- Immunoregulation Section, Laboratory of Immunology and Molecular Biology, National Institute on Aging, Baltimore, MD, USA.
| |
Collapse
|
13
|
Palomba NP, Martinello K, Cocozza G, Casciato S, Mascia A, Di Gennaro G, Morace R, Esposito V, Wulff H, Limatola C, Fucile S. ATP-evoked intracellular Ca 2+ transients shape the ionic permeability of human microglia from epileptic temporal cortex. J Neuroinflammation 2021; 18:44. [PMID: 33588880 PMCID: PMC7883449 DOI: 10.1186/s12974-021-02096-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 02/02/2021] [Indexed: 12/18/2022] Open
Abstract
Background Intracellular Ca2+ modulates several microglial activities, such as proliferation, migration, phagocytosis, and inflammatory mediator secretion. Extracellular ATP, the levels of which significantly change during epileptic seizures, activates specific receptors leading to an increase of intracellular free Ca2+ concentration ([Ca2+]i). Here, we aimed to functionally characterize human microglia obtained from cortices of subjects with temporal lobe epilepsy, focusing on the Ca2+-mediated response triggered by purinergic signaling. Methods Fura-2 based fluorescence microscopy was used to measure [Ca2+]i in primary cultures of human microglial cells obtained from surgical specimens. The perforated patch-clamp technique, which preserves the cytoplasmic milieu, was used to measure ATP-evoked Ca2+-dependent whole-cell currents. Results In human microglia extracellular ATP evoked [Ca2+]i increases depend on Ca2+ entry from the extracellular space and on Ca2+ mobilization from intracellular compartments. Extracellular ATP also induced a transient fivefold potentiation of the total transmembrane current, which was completely abolished when [Ca2+]i increases were prevented by removing external Ca2+ and using an intracellular Ca2+ chelator. TRAM-34, a selective KCa3.1 blocker, significantly reduced the ATP-induced current potentiation but did not abolish it. The removal of external Cl− in the presence of TRAM-34 further lowered the ATP-evoked effect. A direct comparison between the ATP-evoked mean current potentiation and mean Ca2+ transient amplitude revealed a linear correlation. Treatment of microglial cells with LPS for 48 h did not prevent the ATP-induced Ca2+ mobilization but completely abolished the ATP-mediated current potentiation. The absence of the Ca2+-evoked K+ current led to a less sustained ATP-evoked Ca2+ entry, as shown by the faster Ca2+ transient kinetics observed in LPS-treated microglia. Conclusions Our study confirms a functional role for KCa3.1 channels in human microglia, linking ATP-evoked Ca2+ transients to changes in membrane conductance, with an inflammation-dependent mechanism, and suggests that during brain inflammation the KCa3.1-mediated microglial response to purinergic signaling may be reduced. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-021-02096-0.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | - Vincenzo Esposito
- IRCCS Neuromed, Pozzilli, IS, Italy.,Department of Human Neurosciences, Sapienza Rome University, Rome, Italy
| | - Heike Wulff
- Department of Pharmacology, University of California, Davis, CA, USA
| | - Cristina Limatola
- IRCCS Neuromed, Pozzilli, IS, Italy.,Department of Physiology and Pharmacology "V. Erspamer", Sapienza Rome University, Rome, Italy
| | - Sergio Fucile
- IRCCS Neuromed, Pozzilli, IS, Italy.,Department of Physiology and Pharmacology "V. Erspamer", Sapienza Rome University, Rome, Italy
| |
Collapse
|
14
|
Smith PA. K + Channels in Primary Afferents and Their Role in Nerve Injury-Induced Pain. Front Cell Neurosci 2020; 14:566418. [PMID: 33093824 PMCID: PMC7528628 DOI: 10.3389/fncel.2020.566418] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 08/21/2020] [Indexed: 12/12/2022] Open
Abstract
Sensory abnormalities generated by nerve injury, peripheral neuropathy or disease are often expressed as neuropathic pain. This type of pain is frequently resistant to therapeutic intervention and may be intractable. Numerous studies have revealed the importance of enduring increases in primary afferent excitability and persistent spontaneous activity in the onset and maintenance of peripherally induced neuropathic pain. Some of this activity results from modulation, increased activity and /or expression of voltage-gated Na+ channels and hyperpolarization-activated cyclic nucleotide-gated (HCN) channels. K+ channels expressed in dorsal root ganglia (DRG) include delayed rectifiers (Kv1.1, 1.2), A-channels (Kv1.4, 3.3, 3.4, 4.1, 4.2, and 4.3), KCNQ or M-channels (Kv7.2, 7.3, 7.4, and 7.5), ATP-sensitive channels (KIR6.2), Ca2+-activated K+ channels (KCa1.1, 2.1, 2.2, 2.3, and 3.1), Na+-activated K+ channels (KCa4.1 and 4.2) and two pore domain leak channels (K2p; TWIK related channels). Function of all K+ channel types is reduced via a multiplicity of processes leading to altered expression and/or post-translational modification. This also increases excitability of DRG cell bodies and nociceptive free nerve endings, alters axonal conduction and increases neurotransmitter release from primary afferent terminals in the spinal dorsal horn. Correlation of these cellular changes with behavioral studies provides almost indisputable evidence for K+ channel dysfunction in the onset and maintenance of neuropathic pain. This idea is underlined by the observation that selective impairment of just one subtype of DRG K+ channel can produce signs of pain in vivo. Whilst it is established that various mediators, including cytokines and growth factors bring about injury-induced changes in DRG function and excitability, evidence presently available points to a seminal role for interleukin 1β (IL-1β) in control of K+ channel function. Despite the current state of knowledge, attempts to target K+ channels for therapeutic pain management have met with limited success. This situation may change with the advent of personalized medicine. Identification of specific sensory abnormalities and genetic profiling of individual patients may predict therapeutic benefit of K+ channel activators.
Collapse
Affiliation(s)
- Peter A. Smith
- Department of Pharmacology and Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| |
Collapse
|
15
|
Kim E, Otgontenger U, Jamsranjav A, Kim SS. Deleterious Alteration of Glia in the Brain of Alzheimer's Disease. Int J Mol Sci 2020; 21:ijms21186676. [PMID: 32932623 PMCID: PMC7555758 DOI: 10.3390/ijms21186676] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/09/2020] [Accepted: 09/10/2020] [Indexed: 02/07/2023] Open
Abstract
The deterioration of neurons in Alzheimer’s disease (AD) arises from genetic, immunologic, and cellular factors inside the cortex. The traditional consensus of the amyloid-beta (Aβ) paradigm as a singular cause of AD has been under revision, with the accumulation of exploding neurobiological evidence. Among the multifaceted casualties of AD, the involvement of glia gains significance for its dynamic contribution to neurons, either in a neuroprotective or neurotoxic fashion. Basically, microglia and astrocytes contribute to neuronal sustainability by releasing neuroprotective cytokines, maintaining an adequate amount of glutamate in the synapse, and pruning excessive synaptic terminals. Such beneficial effects divert to the other detrimental cascade in chronic neuroinflammatory conditions. In this change, there are new discoveries of specific cytokines, microRNAs, and complementary factors. Previously unknown mechanisms of ion channels such as Kv1.3, Kir2.1, and HCN are also elucidated in the activation of microglia. The activation of glia is responsible for the excitotoxicity through the overflow of glutamate transmitter via mGluRs expressed on the membrane, which can lead to synaptic malfunction and engulfment. The communication between microglia and astrocytes is mediated through exosomes as well as cytokines, where numerous pieces of genetic information are transferred in the form of microRNAs. The new findings tell us that the neuronal environment in the AD condition is a far more complicated and dynamically interacting space. The identification of each molecule in the milieu and cellular communication would contribute to a better understanding of AD in the neurobiological perspective, consequently suggesting a possible therapeutic clue.
Collapse
Affiliation(s)
| | | | | | - Sang Seong Kim
- Correspondence: ; Tel.: +82-31-400-5812; Fax: +82-31-400-5958
| |
Collapse
|
16
|
Inflammation: major denominator of obesity, Type 2 diabetes and Alzheimer's disease-like pathology? Clin Sci (Lond) 2020; 134:547-570. [PMID: 32167154 DOI: 10.1042/cs20191313] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 02/27/2020] [Accepted: 02/28/2020] [Indexed: 02/08/2023]
Abstract
Adipose tissue is an active metabolic organ that contributes to processes such as energy storage and utilization and to the production of a number of metabolic agents, such as adipokines, which play a role in inflammation. In this review, we try to elucidate the connections between peripheral inflammation at obesity and Type 2 diabetes and the central inflammatory process. Multiple lines of evidence highlight the importance of peripheral inflammation and its link to neuroinflammation, which can lead to neurodegenerative diseases such as dementia, Alzheimer's disease (AD) and Parkinson's disease. In addition to the accumulation of misfolded amyloid beta (Aβ) peptide and the formation of the neurofibrillary tangles of hyperphosphorylated tau protein in the brain, activated microglia and reactive astrocytes are the main indicators of AD progression. They were found close to Aβ plaques in the brains of both AD patients and rodent models of Alzheimer's disease-like pathology. Cytokines are key players in pro- and anti-inflammatory processes and are also produced by microglia and astrocytes. The interplay of seemingly unrelated pathways between the periphery and the brain could, in fact, have a common denominator, with inflammation in general being a key factor affecting neuronal processes in the brain. An increased amount of white adipose tissue throughout the body seems to be an important player in pro-inflammatory processes. Nevertheless, other important factors should be studied to elucidate the pathological processes of and the relationship among obesity, Type 2 diabetes and neurodegenerative diseases.
Collapse
|
17
|
Tajti G, Wai DCC, Panyi G, Norton RS. The voltage-gated potassium channel K V1.3 as a therapeutic target for venom-derived peptides. Biochem Pharmacol 2020; 181:114146. [PMID: 32653588 DOI: 10.1016/j.bcp.2020.114146] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 07/05/2020] [Accepted: 07/07/2020] [Indexed: 02/07/2023]
Abstract
The voltage-gated potassium channel KV1.3 is a well-established therapeutic target for a range of autoimmune diseases, in addition to being the site of action of many venom-derived peptides. Numerous studies have documented the efficacy of venom peptides that target KV1.3, in particular from sea anemones and scorpions, in animal models of autoimmune diseases such as rheumatoid arthritis, psoriasis and multiple sclerosis. Moreover, an analogue of the sea anemone peptide ShK (known as dalazatide) has successfully completed Phase 1 clinical trials in mild-to-moderate plaque psoriasis. In this article we consider other potential therapeutic applications of inhibitors of KV1.3, including in inflammatory bowel disease and neuroinflammatory conditions such as Alzheimer's and Parkinson's diseases, as well as fibrotic diseases. We also summarise strategies for facilitating the entry of peptides to the central nervous system, given that this will be a pre-requisite for the treatment of most neuroinflammatory diseases. Venom-derived peptides that have been reported recently to target KV1.3 are also described. The increasing number of autoimmune and other conditions in which KV1.3 is upregulated and is therefore a potential therapeutic target, combined with the fact that many venom-derived peptides are potent inhibitors of KV1.3, suggests that venoms are likely to continue to serve as a rich source of new pharmacological tools and therapeutic leads targeting this channel.
Collapse
Affiliation(s)
- Gabor Tajti
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary.
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, VIC 3052, Australia.
| |
Collapse
|
18
|
Rahmati M, Silva EA, Reseland JE, A Heyward C, Haugen HJ. Biological responses to physicochemical properties of biomaterial surface. Chem Soc Rev 2020; 49:5178-5224. [PMID: 32642749 DOI: 10.1039/d0cs00103a] [Citation(s) in RCA: 137] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Biomedical scientists use chemistry-driven processes found in nature as an inspiration to design biomaterials as promising diagnostic tools, therapeutic solutions, or tissue substitutes. While substantial consideration is devoted to the design and validation of biomaterials, the nature of their interactions with the surrounding biological microenvironment is commonly neglected. This gap of knowledge could be owing to our poor understanding of biochemical signaling pathways, lack of reliable techniques for designing biomaterials with optimal physicochemical properties, and/or poor stability of biomaterial properties after implantation. The success of host responses to biomaterials, known as biocompatibility, depends on chemical principles as the root of both cell signaling pathways in the body and how the biomaterial surface is designed. Most of the current review papers have discussed chemical engineering and biological principles of designing biomaterials as separate topics, which has resulted in neglecting the main role of chemistry in this field. In this review, we discuss biocompatibility in the context of chemistry, what it is and how to assess it, while describing contributions from both biochemical cues and biomaterials as well as the means of harmonizing them. We address both biochemical signal-transduction pathways and engineering principles of designing a biomaterial with an emphasis on its surface physicochemistry. As we aim to show the role of chemistry in the crosstalk between the surface physicochemical properties and body responses, we concisely highlight the main biochemical signal-transduction pathways involved in the biocompatibility complex. Finally, we discuss the progress and challenges associated with the current strategies used for improving the chemical and physical interactions between cells and biomaterial surface.
Collapse
Affiliation(s)
- Maryam Rahmati
- Department of Biomaterials, Institute of Clinical Dentistry, University of Oslo, 0317 Oslo, Norway. h.j.haugen.odont.uio.no
| | | | | | | | | |
Collapse
|
19
|
Saddala MS, Lennikov A, Mukwaya A, Yang Y, Hill MA, Lagali N, Huang H. Discovery of novel L-type voltage-gated calcium channel blockers and application for the prevention of inflammation and angiogenesis. J Neuroinflammation 2020; 17:132. [PMID: 32334630 PMCID: PMC7183139 DOI: 10.1186/s12974-020-01801-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 04/02/2020] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND The ways in which microglia activate and promote neovascularization (NV) are not fully understood. Recent in vivo evidence supports the theory that calcium is required for the transition of microglia from a surveillance state to an active one. The objectives of this study were to discover novel L-type voltage-gated channel (L-VGCC) blockers and investigate their application for the prevention of inflammation and angiogenesis. METHODS Pharmacophore-based computational modeling methods were used to screen for novel calcium channel blockers (CCBs) from the ZINC compound library. The effects of CCBs on calcium blockade, microglial pro-inflammatory activation, and cell toxicity were validated in BV-2 microglial cell and freshly isolated smooth muscle cell (SMC) cultures. Laser-induced choroidal neovascularization (NV) and the suture-induced inflammatory corneal NV models of angiogenesis were used for in vivo validation of the novel CCBs. CX3CR1gfp/+ mice were used to examine the infiltration of GFP-labeled microglial cells. RESULTS We identified three compounds from the ZINC database (Zinc20267861, Zinc18204217, and Zinc33254827) as new blockers of L-type voltage-gated calcium channels (L-VGCC) using a structure-based pharmacophore approach. The effects of the three CCBs on Ca2+ influx into cells were verified in BV-2 microglial cells using Fura-2 fluorescent dye and in freshly isolated SMCs using the voltage-patch clamp. All three CCBs reduced microglial cell migration, activation stimulated by lipopolysaccharide (LPS), and reduced the expression of the inflammatory markers NF-κB (phospho-IκBα) and cyclooxygenase-2 (COX-2) as well as reactive oxygen species. Of the three compounds, we further examined the in vivo activity of Zinc20267861. Topical treatment with Zinc20267861 in a rat model of suture-induced inflammatory cornea neovascularization demonstrated efficacy of the compound in reducing monocyte infiltration and overall corneal NV response. Subconjunctival administration of the compound in the choroidal NV mouse model effectively prevented CNV and microglial infiltration. CONCLUSIONS Our findings suggest that the novel CCBs identified here are effective anti-inflammatory agents that can be further evaluated for treating NV disorders and can be potentially applied in the treatment of ocular inflammatory and pathological angiogenetic disorders.
Collapse
Affiliation(s)
- Madhu Sudhana Saddala
- Department of Ophthalmology, School of Medicine, University of Missouri-Columbia, 1 Hospital Drive, MA102C, Columbia, MO, 65212, USA
| | - Anton Lennikov
- Department of Ophthalmology, School of Medicine, University of Missouri-Columbia, 1 Hospital Drive, MA102C, Columbia, MO, 65212, USA
| | - Anthony Mukwaya
- Department of Ophthalmology, Institute for Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
| | - Yan Yang
- Dalton Cardiovascular Research Center, University of Missouri-Columbia, Columbia, MO, USA
| | - Michael A Hill
- Dalton Cardiovascular Research Center, University of Missouri-Columbia, Columbia, MO, USA
| | - Neil Lagali
- Department of Ophthalmology, Institute for Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
| | - Hu Huang
- Department of Ophthalmology, School of Medicine, University of Missouri-Columbia, 1 Hospital Drive, MA102C, Columbia, MO, 65212, USA.
| |
Collapse
|
20
|
Vay SU, Flitsch LJ, Rabenstein M, Monière H, Jakovcevski I, Andjus P, Bijelic D, Blaschke S, Walter HL, Fink GR, Schroeter M, Rueger MA. The impact of hyperpolarization-activated cyclic nucleotide-gated (HCN) and voltage-gated potassium KCNQ/Kv7 channels on primary microglia function. J Neuroinflammation 2020; 17:100. [PMID: 32248813 PMCID: PMC7132998 DOI: 10.1186/s12974-020-01779-4] [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: 01/16/2020] [Accepted: 03/18/2020] [Indexed: 01/03/2023] Open
Abstract
Background Microglia are essential to maintain cell homeostasis in the healthy brain and are activated after brain injury. Upon activation, microglia polarize towards different phenotypes. The course of microglia activation is complex and depends on signals in the surrounding milieu. Recently, it has been suggested that microglia respond to ion currents, as a way of regulating their activity and function. Methods and results Under the hypothesis that HCN and KCNQ/Kv7 channels impact on microglia, we studied primary rat microglia in the presence or absence of specific pharmacological blockade or RNA silencing. Primary microglia expressed the subunits HCN1-4, Kv7.2, Kv7.3, and Kv7.5. The expression of HCN2, as well as Kv7.2 and Kv7.3, varied among different microglia phenotypes. The pharmacological blockade of HCN channels by ZD7288 resulted in cell depolarization with slowly rising intracellular calcium levels, leading to enhanced survival and reduced proliferation rates of resting microglia. Furthermore, ZD7288 treatment, as well as knockdown of HCN2 RNA by small interfering RNA, resulted in an attenuation of later microglia activation—both towards the anti- and pro-inflammatory phenotype. However, HCN channel inhibition enhanced the phagocytic capacity of IL4-stimulated microglia. Blockade of Kv7/KCNQ channel by XE-991 exclusively inhibited the migratory capacity of resting microglia. Conclusion These observations suggest that the HCN current contributes to various microglia functions and impacts on the course of microglia activation, while the Kv7/KCNQ channels affect microglia migration. Characterizing the role of HCN channels in microglial functioning may offer new therapeutic approaches for targeted modulation of neuroinflammation as a hallmark of various neurological disorders.
Collapse
Affiliation(s)
- Sabine Ulrike Vay
- Department of Neurology, Faculty of Medicine and University Hospital, University Hospital of Cologne, Kerpener Strasse 62, 50924, Cologne, Germany.
| | - Lea Jessica Flitsch
- Department of Neurology, Faculty of Medicine and University Hospital, University Hospital of Cologne, Kerpener Strasse 62, 50924, Cologne, Germany
| | - Monika Rabenstein
- Department of Neurology, Faculty of Medicine and University Hospital, University Hospital of Cologne, Kerpener Strasse 62, 50924, Cologne, Germany
| | - Helena Monière
- Department of Neurology, Faculty of Medicine and University Hospital, University Hospital of Cologne, Kerpener Strasse 62, 50924, Cologne, Germany
| | - Igor Jakovcevski
- Institute for Molecular and Behavioural Neuroscience and Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | - Pavle Andjus
- Center for Laser Microscopy-CLM, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Dunja Bijelic
- Center for Laser Microscopy-CLM, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Stefan Blaschke
- Department of Neurology, Faculty of Medicine and University Hospital, University Hospital of Cologne, Kerpener Strasse 62, 50924, Cologne, Germany.,Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Centre Juelich, Juelich, Germany
| | - Helene Luise Walter
- Department of Neurology, Faculty of Medicine and University Hospital, University Hospital of Cologne, Kerpener Strasse 62, 50924, Cologne, Germany
| | - Gereon Rudolf Fink
- Department of Neurology, Faculty of Medicine and University Hospital, University Hospital of Cologne, Kerpener Strasse 62, 50924, Cologne, Germany.,Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Centre Juelich, Juelich, Germany
| | - Michael Schroeter
- Department of Neurology, Faculty of Medicine and University Hospital, University Hospital of Cologne, Kerpener Strasse 62, 50924, Cologne, Germany.,Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Centre Juelich, Juelich, Germany
| | - Maria Adele Rueger
- Department of Neurology, Faculty of Medicine and University Hospital, University Hospital of Cologne, Kerpener Strasse 62, 50924, Cologne, Germany.,Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Centre Juelich, Juelich, Germany
| |
Collapse
|
21
|
Deletion of Voltage-Gated Calcium Channels in Astrocytes during Demyelination Reduces Brain Inflammation and Promotes Myelin Regeneration in Mice. J Neurosci 2020; 40:3332-3347. [PMID: 32169969 DOI: 10.1523/jneurosci.1644-19.2020] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 02/28/2020] [Accepted: 03/03/2020] [Indexed: 12/28/2022] Open
Abstract
To determine whether Cav1.2 voltage-gated Ca2+ channels contribute to astrocyte activation, we generated an inducible conditional knock-out mouse in which the Cav1.2 α subunit was deleted in GFAP-positive astrocytes. This astrocytic Cav1.2 knock-out mouse was tested in the cuprizone model of myelin injury and repair which causes astrocyte and microglia activation in the absence of a lymphocytic response. Deletion of Cav1.2 channels in GFAP-positive astrocytes during cuprizone-induced demyelination leads to a significant reduction in the degree of astrocyte and microglia activation and proliferation in mice of either sex. Concomitantly, the production of proinflammatory factors such as TNFα, IL1β and TGFβ1 was significantly decreased in the corpus callosum and cortex of Cav1.2 knock-out mice through demyelination. Furthermore, this mild inflammatory environment promotes oligodendrocyte progenitor cells maturation and myelin regeneration across the remyelination phase of the cuprizone model. Similar results were found in animals treated with nimodipine, a Cav1.2 Ca2+ channel inhibitor with high affinity to the CNS. Mice of either sex injected with nimodipine during the demyelination stage of the cuprizone treatment displayed a reduced number of reactive astrocytes and showed a faster and more efficient brain remyelination. Together, these results indicate that Cav1.2 Ca2+ channels play a crucial role in the induction and proliferation of reactive astrocytes during demyelination; and that attenuation of astrocytic voltage-gated Ca2+ influx may be an effective therapy to reduce brain inflammation and promote myelin recovery in demyelinating diseases.SIGNIFICANCE STATEMENT Reducing voltage-gated Ca2+ influx in astrocytes during brain demyelination significantly attenuates brain inflammation and astrocyte reactivity. Furthermore, these changes promote myelin restoration and oligodendrocyte maturation throughout remyelination.
Collapse
|
22
|
Saw G, Krishna K, Gupta N, Soong TW, Mallilankaraman K, Sajikumar S, Dheen ST. Epigenetic regulation of microglial phosphatidylinositol 3-kinase pathway involved in long-term potentiation and synaptic plasticity in rats. Glia 2019; 68:656-669. [PMID: 31702864 PMCID: PMC7003906 DOI: 10.1002/glia.23748] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 10/17/2019] [Accepted: 10/25/2019] [Indexed: 12/16/2022]
Abstract
Microglia are the main form of immune defense in the central nervous system. Microglia express phosphatidylinositol 3‐kinase (PI3K), which has been shown to play a significant role in synaptic plasticity in neurons and inflammation via microglia. This study shows that microglial PI3K is regulated epigenetically through histone modifications and posttranslationally through sumoylation and is involved in long‐term potentiation (LTP) by modulating the expression of brain‐derived neurotrophic factor (BDNF), which has been shown to be involved in neuronal synaptic plasticity. Sodium butyrate, a histone deacetylase inhibitor, upregulates PI3K expression, the phosphorylation of its downstream effectors, AKT and cAMP response element‐binding protein (CREB), and the expression of BDNF in microglia, suggesting that BDNF secretion is regulated in microglia via epigenetic regulation of PI3K. Further, knockdown of SUMO1 in BV2 microglia results in a decrease in the expression of PI3K, the phosphorylation of AKT and CREB, as well as the expression of BDNF. These results suggest that microglial PI3K is epigenetically regulated by histone modifications and posttranslationally modified by sumoylation, leading to altered expression of BDNF. Whole‐cell voltage‐clamp showed the involvement of microglia in neuronal LTP, as selective ablation or disruption of microglia with clodronate in rat hippocampal slices abolished LTP. However, LTP was rescued when the same hippocampal slices were treated with active PI3K or BDNF, indicating that microglial PI3K/AKT signaling contributes to LTP and synaptic plasticity. Understanding the mechanisms by which microglial PI3K influences synapses provides insights into the ways it can modulate synaptic transmission and plasticity in learning and memory.
Collapse
Affiliation(s)
- Genevieve Saw
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Kumar Krishna
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Neelima Gupta
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Tuck Wah Soong
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Karthik Mallilankaraman
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Sreedharan Sajikumar
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - S Thameem Dheen
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| |
Collapse
|
23
|
Bozic I, Savic D, Milosevic A, Janjic M, Laketa D, Tesovic K, Bjelobaba I, Jakovljevic M, Nedeljkovic N, Pekovic S, Lavrnja I. The Potassium Channel Kv1.5 Expression Alters During Experimental Autoimmune Encephalomyelitis. Neurochem Res 2019; 44:2733-2745. [PMID: 31624998 DOI: 10.1007/s11064-019-02892-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/23/2019] [Accepted: 10/11/2019] [Indexed: 12/29/2022]
Abstract
Multiple sclerosis (MS) is a chronic, inflammatory, neurodegenerative disease with an autoimmune component. It was suggested that potassium channels, which are involved in crucial biological functions may have a role in different diseases, including MS and its animal model, experimental autoimmune encephalomyelitis (EAE). It was shown that voltage-gated potassium channels Kv1.5 are responsible for fine-tuning in the immune physiology and influence proliferation and differentiation in microglia and astrocytes. Here, we explored the cellular distribution of the Kv1.5 channel, together with its transcript and protein expression in the male rat spinal cord during different stages of EAE. Our results reveal a decrease of Kv1.5 transcript and protein level at the peak of disease, where massive infiltration of myeloid cells occurs, together with reactive astrogliosis and demyelination. Also, we revealed that the presence of this channel is not found in infiltrating macrophages/microglia during EAE. It is interesting to note that Kv1.5 channel is expressed only in resting microglia in the naïve animals. Predominant expression of Kv1.5 channel was found in the astrocytes in all experimental groups, while some vimentin+ cells, resembling macrophages, are devoid of Kv1.5 expression. Our results point to the possible link between Kv1.5 channel and the pathophysiological processes in EAE.
Collapse
Affiliation(s)
- I Bozic
- Department of Neurobiology, Institute for Biological Research "Siniša Stanković"- National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - D Savic
- Department of Neurobiology, Institute for Biological Research "Siniša Stanković"- National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - A Milosevic
- Department of Neurobiology, Institute for Biological Research "Siniša Stanković"- National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - M Janjic
- Department of Neurobiology, Institute for Biological Research "Siniša Stanković"- National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - D Laketa
- Department for General Physiology and Biophysics, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - K Tesovic
- Department of Neurobiology, Institute for Biological Research "Siniša Stanković"- National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - I Bjelobaba
- Department of Neurobiology, Institute for Biological Research "Siniša Stanković"- National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - M Jakovljevic
- Department of Neurobiology, Institute for Biological Research "Siniša Stanković"- National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - N Nedeljkovic
- Department for General Physiology and Biophysics, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - S Pekovic
- Department of Neurobiology, Institute for Biological Research "Siniša Stanković"- National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - I Lavrnja
- Department of Neurobiology, Institute for Biological Research "Siniša Stanković"- National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia.
| |
Collapse
|
24
|
Electrophysiological Investigation of Microglia. Methods Mol Biol 2019. [PMID: 31392681 DOI: 10.1007/978-1-4939-9658-2_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Although microglial cells are not electrically excitable, they express a large repertoire of ion channels that are activated by voltage, stretch, extracellular ligands, or intracellular pathways (e.g. Ca2+, G-proteins). The patch-clamp technique is the electrophysiological method of choice to study these channels whose expression varies largely in pathological conditions but also during normal development and aging. This chapter focuses on protocols allowing the recording and the analysis of these channels in acute brain slices, with a particular emphasis on the study of channels activated by extracellular ligands.
Collapse
|
25
|
Tenza-Ferrer H, Magno LAV, Romano-Silva MA, da Silva JF, Gomez MV. Phα1β Spider Toxin Reverses Glial Structural Plasticity Upon Peripheral Inflammation. Front Cell Neurosci 2019; 13:306. [PMID: 31354431 PMCID: PMC6635560 DOI: 10.3389/fncel.2019.00306] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 06/24/2019] [Indexed: 01/03/2023] Open
Abstract
The incoming signals from injured sensory neurons upon peripheral inflammation are processed in the dorsal horn of spinal cord, where glial cells accumulate and play a critical role in initiating allodynia (increased pain in response to light-touch). However, how painful stimuli in the periphery engage glial reactivity in the spinal cord remains unclear. Here, we found that a hind paw inflammation induced by CFA produces robust morphological changes in spinal astrocytes and microglia compatible with the reactive phenotype. Strikingly, we discovered that a single intrathecal injection with venom peptides that inhibit calcium channels reversed all the glial pathological features of the peripheral inflammation. These effects were more apparent in rats treated with the Phα1β spider toxin (non-specific calcium channel antagonist) than ω-MVIIA cone snail toxin (selective N-type calcium channel antagonist). These data reveal for the first time a venom peptide acting on glial structural remodeling in vivo. We, therefore, suggest that calcium-dependent plasticity is an essential trigger for glial cells to initiate reactivity, which may represent a new target for the antinociceptive effects of Phα1β and ω-MVIIA toxins in inflammatory pain conditions.
Collapse
Affiliation(s)
- Helia Tenza-Ferrer
- Centro de Tecnologia em Medicina Molecular, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Luiz Alexandre Viana Magno
- Centro de Tecnologia em Medicina Molecular, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Marco Aurélio Romano-Silva
- Centro de Tecnologia em Medicina Molecular, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil.,Departamento de Saúde Mental, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Juliana Figueira da Silva
- Centro de Tecnologia em Medicina Molecular, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil.,Laboratório de Toxinas, Instituto de Ensino e Pesquisa da Santa Casa de Belo Horizonte, Belo Horizonte, Brazil
| | - Marcus Vinicius Gomez
- Centro de Tecnologia em Medicina Molecular, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brazil.,Laboratório de Toxinas, Instituto de Ensino e Pesquisa da Santa Casa de Belo Horizonte, Belo Horizonte, Brazil
| |
Collapse
|
26
|
Chun BJ, Stewart BD, Vaughan DD, Bachstetter AD, Kekenes-Huskey PM. Simulation of P2X-mediated calcium signalling in microglia. J Physiol 2018; 597:799-818. [PMID: 30462840 DOI: 10.1113/jp277377] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 11/19/2018] [Indexed: 12/11/2022] Open
Abstract
KEY POINTS A computational model of P2X channel activation in microglia was developed that includes downfield Ca2+ -dependent signalling pathways. This model provides quantitative insights into how diverse signalling pathways in microglia converge to control microglial function. ABSTRACT Microglia function is orchestrated through highly coupled signalling pathways that depend on calcium (Ca2+ ). In response to extracellular ATP, transient increases in intracellular Ca2+ driven through the activation of purinergic receptors, P2X and P2Y, are sufficient to promote cytokine synthesis. Although the steps comprising the pathways bridging purinergic receptor activation with transcriptional responses have been probed in great detail, a quantitative model for how these steps collectively control cytokine production has not been established. Here we developed a minimal computational model that quantitatively links extracellular stimulation of two prominent ionotropic purinergic receptors, P2X4 and P2X7, with the graded production of a gene product, namely the tumour necrosis factor α (TNFα) cytokine. In addition to Ca2+ handling mechanisms common to eukaryotic cells, our model includes microglia-specific processes including ATP-dependent P2X4 and P2X7 activation, activation of nuclear factor of activated T-cells (NFAT) transcription factors, and TNFα production. Parameters for this model were optimized to reproduce published data for these processes, where available. With this model, we determined the propensity for TNFα production in microglia, subject to a wide range of ATP exposure amplitudes, frequencies and durations that the cells could encounter in vivo. Furthermore, we have investigated the extent to which modulation of the signal transduction pathways influence TNFα production. Our results suggest that pulsatile stimulation of P2X4 via micromolar ATP may be sufficient to promote TNFα production, whereas high-amplitude ATP exposure is necessary for production via P2X7. Furthermore, under conditions that increase P2X4 expression, for instance, following activation by pathogen-associated molecular factors, P2X4-associated TNFα production is greatly enhanced. Given that Ca2+ homeostasis in microglia is profoundly important to its function, this computational model provides a quantitative framework to explore hypotheses pertaining to microglial physiology.
Collapse
Affiliation(s)
- Byeong Jae Chun
- Department of Chemistry, University of Kentucky, Lexington, KY, USA
| | | | - Darin D Vaughan
- Department of Chemistry, University of Kentucky, Lexington, KY, USA
| | | | | |
Collapse
|
27
|
López-López JR, Cidad P, Pérez-García MT. Kv channels and vascular smooth muscle cell proliferation. Microcirculation 2018; 25. [PMID: 29110368 DOI: 10.1111/micc.12427] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 10/30/2017] [Indexed: 12/12/2022]
Abstract
Kv channels are present in virtually all VSMCs and strongly influence contractile responses. However, they are also instrumental in the proliferative, migratory, and secretory functions of synthetic, dedifferentiated VSMCs upon PM. In fact, Kv channels not only contribute to all these processes but also are active players in the phenotypic switch itself. This review is focused on the role(s) of Kv channels in VSMC proliferation, which is one of the best characterized functions of dedifferentiated VSMCs. VSMC proliferation is a complex process requiring specific Kv channels at specific time and locations. Their identification is further complicated by their large diversity and the differences in expression across vascular beds. Of interest, both conserved changes in some Kv channels and vascular bed-specific regulation of others seem to coexist and participate in VSMC proliferation through complementary mechanisms. Such a system will add flexibility to the process while providing the required robustness to preserve this fundamental cellular response.
Collapse
Affiliation(s)
- José R López-López
- Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| | - Pilar Cidad
- Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| | - M Teresa Pérez-García
- Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| |
Collapse
|
28
|
Mustaly-Kalimi S, Littlefield AM, Stutzmann GE. Calcium Signaling Deficits in Glia and Autophagic Pathways Contributing to Neurodegenerative Disease. Antioxid Redox Signal 2018; 29:1158-1175. [PMID: 29634342 DOI: 10.1089/ars.2017.7266] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
SIGNIFICANCE Numerous cellular processes and signaling mechanisms have been identified that contribute to Alzheimer's disease (AD) pathology; however, a comprehensive or unifying pathway that binds together the major disease features remains elusive. As an upstream mechanism, altered calcium (Ca2+) signaling is a common driving force for many pathophysiological events that emerge during normal aging and development of neurodegenerative disease. Recent Advances: Over the previous three decades, accumulated evidence has validated the concept that intracellular Ca2+ dysregulation is centrally involved in AD pathogenesis, including the aggregation of pathogenic β-amyloid (Aβ) and phospho-τ species, synapse loss and dysfunction, cognitive impairment, and neurotoxicity. CRITICAL ISSUES Although neuronal Ca2+ signaling within the cytosol and endoplasmic reticulum (ER) has been well studied, other critical central nervous system-resident cell types affected by aberrant Ca2+ signaling, such as astrocytes and microglia, have not been considered as thoroughly. In addition, certain intracellular Ca2+-harboring organelles have been well studied, such as the ER and mitochondria; however other critical Ca2+-regulated organelles, such as lysosomes and autophagosomes, have only more recently been investigated. In this review, we examine Ca2+ dysregulation in microglia and astrocytes, as well as key intracellular organelles important for cellular maintenance and protein handling. Ca2+ dysregulation within these non-neuronal cells and organelles is hypothesized to disrupt the effective clearance of misaggregated proteins and cellular signaling pathways needed for memory networks. FUTURE DIRECTIONS Overall, we aim to explore how these disrupted mechanisms could be involved in AD pathology and consider their role as potential therapeutic targets. Antioxid. Redox Signal. 29, 1158-1175.
Collapse
Affiliation(s)
- Sarah Mustaly-Kalimi
- 1 Department of Neuroscience, School of Graduate and Postdoctoral Studies, Rosalind Franklin University of Medicine and Science , North Chicago, Illinois
| | - Alyssa M Littlefield
- 1 Department of Neuroscience, School of Graduate and Postdoctoral Studies, Rosalind Franklin University of Medicine and Science , North Chicago, Illinois
| | - Grace E Stutzmann
- 2 Department of Neuroscience, The Chicago Medical School, Rosalind Franklin University of Medicine and Science , North Chicago, Illinois
| |
Collapse
|
29
|
Age-Induced Spatial Memory Deficits in Rats Are Correlated with Specific Brain Region Alterations in Microglial Morphology and Gene Expression. J Neuroimmune Pharmacol 2018; 14:251-262. [DOI: 10.1007/s11481-018-9817-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 10/12/2018] [Indexed: 10/28/2022]
|
30
|
Lively S, Schlichter LC. Microglia Responses to Pro-inflammatory Stimuli (LPS, IFNγ+TNFα) and Reprogramming by Resolving Cytokines (IL-4, IL-10). Front Cell Neurosci 2018; 12:215. [PMID: 30087595 PMCID: PMC6066613 DOI: 10.3389/fncel.2018.00215] [Citation(s) in RCA: 214] [Impact Index Per Article: 35.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 06/28/2018] [Indexed: 12/11/2022] Open
Abstract
Microglia respond to CNS injuries and diseases with complex reactions, often called "activation." A pro-inflammatory phenotype (also called classical or M1 activation) lies at one extreme of the reactivity spectrum. There were several motivations for this study. First, bacterial endotoxin (lipopolysaccharide, LPS) is the most commonly used pro-inflammatory stimulus for microglia, both in vitro and in vivo; however, pro-inflammatory cytokines (e.g., IFNγ, TNFα) rather than LPS will be encountered with sterile CNS damage and disease. We lack direct comparisons of responses between LPS and such cytokines. Second, while transcriptional profiling is providing substantial data on microglial responses to LPS, these studies mainly use mouse cells and models, and there is increasing evidence that responses of rat microglia can differ. Third, the cytokine milieu is dynamic after acute CNS damage, and an important question in microglial biology is: How malleable are their responses? There are very few studies of effects of resolving cytokines, particularly for rat microglia, and much of the work has focused on pro-inflammatory outcomes. Here, we first exposed primary rat microglia to LPS or to IFNγ+TNFα (I+T) and compared hallmark functional (nitric oxide production, migration) and molecular responses (almost 100 genes), including surface receptors that can be considered part of the sensome. Protein changes for exemplary molecules were also quantified: ARG1, CD206/MRC1, COX-2, iNOS, and PYK2. Despite some similarities, there were notable differences in responses to LPS and I+T. For instance, LPS often evoked higher pro-inflammatory gene expression and also increased several anti-inflammatory genes. Second, we compared the ability of two anti-inflammatory, resolving cytokines (IL-4, IL-10), to counteract responses to LPS and I+T. IL-4 was more effective after I+T than after LPS, and IL-10 was surprisingly ineffective after either stimulus. These results should prove useful in modeling microglial reactivity in vitro; and comparing transcriptional responses to sterile CNS inflammation in vivo.
Collapse
Affiliation(s)
- Starlee Lively
- Division of Genetics & Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
| | - Lyanne C Schlichter
- Division of Genetics & Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
31
|
Lively S, Lam D, Wong R, Schlichter LC. Comparing Effects of Transforming Growth Factor β1 on Microglia From Rat and Mouse: Transcriptional Profiles and Potassium Channels. Front Cell Neurosci 2018; 12:115. [PMID: 29780305 PMCID: PMC5946019 DOI: 10.3389/fncel.2018.00115] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 04/11/2018] [Indexed: 12/02/2022] Open
Abstract
The cytokine, transforming growth factor β1 (TGFβ1), is up-regulated after central nervous system (CNS) injuries or diseases involving microglial activation, and it has been proposed as a therapeutic agent for treating neuroinflammation. Microglia can produce and respond to TGFβ1. While rats and mice are commonly used for studying neuroinflammation, very few reports directly compare them. Such studies are important for improving pre-clinical studies and furthering translational progress in developing therapeutic interventions. After intracerebral hemorrhage (ICH) in the rat striatum, the TGFβ1 receptor was highly expressed on microglia/macrophages within the hematoma. We recently found species similarities and differences in response to either a pro-inflammatory (interferon-γ, IFN-γ, +tumor necrosis factor, TNF-α) or anti-inflammatory interleukin-4 (IL-4) stimulus. Here, we assessed whether rat and mouse microglia differ in their responses to TGFβ1. Microglia were isolated from Sprague-Dawley rats and C57BL/6 mice and treated with TGFβ1. We quantified changes in expression of >50 genes, in their morphology, proliferation, apoptosis and in three potassium channels that are considered therapeutic targets. Many inflammatory mediators, immune receptors and modulators showed species similarities, but notable differences included that, for some genes, only one species responded (e.g., Il4r, Il10, Tgfbr2, colony-stimulating factor receptor (Csf1r), Itgam, suppressor of cytokine signaling 1 (Socs1), toll-like receptors 4 (Tlr4), P2rx7, P2ry12), and opposite responses were seen for others (Tgfb1, Myc, Ifngr1). In rat only, TGFβ1 affected microglial morphology and proliferation, but there was no apoptosis in either species. In both species, TGFβ1 dramatically increased Kv1.3 channel expression and current (no effects on Kir2.1). KCa3.1 showed opposite species responses: the current was low in unstimulated rat microglia and greatly increased by TGFβ1 but higher in control mouse cells and decreased by TGFβ1. Finally, we compared TGFβ1 and IL10 (often considered similar anti-inflammatory stimuli) and found many different responses in both species. Overall, the numerous species differences should be considered when characterizing neuroinflammation and microglial activation in vitro and in vivo, and when targeting potassium channels.
Collapse
Affiliation(s)
- Starlee Lively
- Krembil Research Institute, Genes and Development Division, University Health Network, Toronto, ON, Canada
| | - Doris Lam
- Krembil Research Institute, Genes and Development Division, University Health Network, Toronto, ON, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Raymond Wong
- Krembil Research Institute, Genes and Development Division, University Health Network, Toronto, ON, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Lyanne C Schlichter
- Krembil Research Institute, Genes and Development Division, University Health Network, Toronto, ON, Canada.,Department of Physiology, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
32
|
Bozic I, Tesovic K, Laketa D, Adzic M, Jakovljevic M, Bjelobaba I, Savic D, Nedeljkovic N, Pekovic S, Lavrnja I. Voltage Gated Potassium Channel Kv1.3 Is Upregulated on Activated Astrocytes in Experimental Autoimmune Encephalomyelitis. Neurochem Res 2018; 43:1020-1034. [PMID: 29574670 DOI: 10.1007/s11064-018-2509-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/13/2018] [Accepted: 03/17/2018] [Indexed: 12/13/2022]
Abstract
Kv1.3 is a voltage gated potassium channel that has been implicated in pathophysiology of multiple sclerosis (MS). In the present study we investigated temporal and cellular expression pattern of this channel in the lumbar part of spinal cords of animals with experimental autoimmune encephalomyelitis (EAE), animal model of MS. EAE was actively induced in female Dark Agouti rats. Expression of Kv1.3 was analyzed at different time points of disease progression, at the onset, peak and end of EAE. We here show that Kv1.3 increased by several folds at the peak of EAE at both gene and protein level. Double immunofluorescence analyses demonstrated localization of Kv1.3 on activated microglia, macrophages, and reactive astrocytes around inflammatory lesions. In vitro experiments showed that pharmacological block of Kv1.3 in activated astrocytes suppresses the expression of proinflammatory mediators, suggesting a role of this channel in inflammation. Our results support the hypothesis that Kv1.3 may be a therapeutic target of interest for MS and add astrocytes to the list of cells whose activation would be suppressed by inhibiting Kv1.3 in inflammatory conditions.
Collapse
Affiliation(s)
- Iva Bozic
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Blvd Despota Stefana 142, 11060, Belgrade, Serbia.
| | - Katarina Tesovic
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Blvd Despota Stefana 142, 11060, Belgrade, Serbia
| | - Danijela Laketa
- Institute of Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Marija Adzic
- Institute of Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Marija Jakovljevic
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Blvd Despota Stefana 142, 11060, Belgrade, Serbia
| | - Ivana Bjelobaba
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Blvd Despota Stefana 142, 11060, Belgrade, Serbia
| | - Danijela Savic
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Blvd Despota Stefana 142, 11060, Belgrade, Serbia
| | - Nadezda Nedeljkovic
- Institute of Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Sanja Pekovic
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Blvd Despota Stefana 142, 11060, Belgrade, Serbia
| | - Irena Lavrnja
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Blvd Despota Stefana 142, 11060, Belgrade, Serbia
| |
Collapse
|
33
|
Plescher M, Seifert G, Hansen JN, Bedner P, Steinhäuser C, Halle A. Plaque-dependent morphological and electrophysiological heterogeneity of microglia in an Alzheimer's disease mouse model. Glia 2018; 66:1464-1480. [PMID: 29493017 DOI: 10.1002/glia.23318] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 01/17/2018] [Accepted: 02/12/2018] [Indexed: 12/18/2022]
Abstract
Microglia, the central nervous system resident innate immune cells, cluster around Aβ plaques in Alzheimer's disease (AD). The activation phenotype of these plaque-associated microglial cells, and their differences to microglia distant to Aβ plaques, are incompletely understood. We used novel three-dimensional cell analysis software to comprehensively analyze the morphological properties of microglia in the TgCRND8 mouse model of AD in spatial relation to Aβ plaques. We found strong morphological changes exclusively in plaque-associated microglia, whereas plaque-distant microglia showed only minor changes. In addition, patch-clamp recordings of microglia in acute cerebral slices of TgCRND8 mice revealed increased K+ currents in plaque-associated but not plaque-distant microglia. Within the subgroup of plaque-associated microglia, two different current profiles were detected. One subset of cells displayed only increased inward currents, while a second subset showed both increased inward and outward currents, implicating that the plaque microenvironment differentially impacts microglial ion channel expression. Using pharmacological channel blockers, multiplex single-cell PCR analysis and RNA fluorescence in situ hybridization, we identified Kir and Kv channel types contributing to the in- and outward K+ conductance in plaque-associated microglia. In summary, we have identified a previously unrecognized level of morphological and electrophysiological heterogeneity of microglia in relation to amyloid plaques, suggesting that microglia may display multiple activation states in AD.
Collapse
Affiliation(s)
- Monika Plescher
- German Center for Neurodegenerative Diseases, DZNE, Bonn, Germany.,Center of Advanced European Studies and Research, Bonn, Germany.,Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Gerald Seifert
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Jan Niklas Hansen
- German Center for Neurodegenerative Diseases, DZNE, Bonn, Germany.,Center of Advanced European Studies and Research, Bonn, Germany
| | - Peter Bedner
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Christian Steinhäuser
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Annett Halle
- German Center for Neurodegenerative Diseases, DZNE, Bonn, Germany.,Center of Advanced European Studies and Research, Bonn, Germany
| |
Collapse
|
34
|
Ciernia AV, Careaga M, Ashwood P, LaSalle J. Microglia from offspring of dams with allergic asthma exhibit epigenomic alterations in genes dysregulated in autism. Glia 2018; 66:505-521. [PMID: 29134693 PMCID: PMC5767155 DOI: 10.1002/glia.23261] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 08/18/2017] [Accepted: 10/25/2017] [Indexed: 12/24/2022]
Abstract
Dysregulation in immune responses during pregnancy increases the risk of a having a child with an autism spectrum disorder (ASD). Asthma is one of the most common chronic diseases among pregnant women, and symptoms often worsen during pregnancy. We recently developed a mouse model of maternal allergic asthma (MAA) that induces changes in sociability, repetitive, and perseverative behaviors in the offspring. Since epigenetic changes help a static genome adapt to the maternal environment, activation of the immune system may epigenetically alter fetal microglia, the brain's resident immune cells. We therefore tested the hypothesis that epigenomic alterations to microglia may be involved in behavioral abnormalities observed in MAA offspring. We used the genome-wide approaches of whole genome bisulfite sequencing to examine DNA methylation and RNA sequencing to examine gene expression in microglia from juvenile MAA offspring. Differentially methylated regions were enriched for immune signaling pathways and important microglial developmental transcription factor binding motifs. Differential expression analysis identified genes involved in controlling microglial sensitivity to the environment and shaping neuronal connections in the developing brain. Differentially expressed genes significantly overlapped genes with altered expression in human ASD cortex, supporting a role for microglia in the pathogenesis of ASD.
Collapse
Affiliation(s)
- Annie Vogel Ciernia
- Medical Microbiology and Immunology, University of California, Davis, Davis, CA 95616
| | - Milo Careaga
- MIND Institute, 2825 50 Street, Sacramento, CA 95817, University of California, Davis
| | - Paul Ashwood
- MIND Institute, 2825 50 Street, Sacramento, CA 95817, University of California, Davis
| | - Janine LaSalle
- Medical Microbiology and Immunology, University of California, Davis, Davis, CA 95616
| |
Collapse
|
35
|
Deftu AF, Ristoiu V, Suter MR. Intrathecal Administration of CXCL1 Enhances Potassium Currents in Microglial Cells. Pharmacology 2018; 101:262-268. [PMID: 29448255 DOI: 10.1159/000486865] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 01/16/2018] [Indexed: 12/11/2022]
Abstract
The functioning of microglial cells inside the central nervous system depends on their ion channels expression. Microglia are capable of synthesizing different cytokines and chemokines, including CXCL1, and responding to their action via specific receptors. In this study, we explore the effect of intrathecal injection of CXCL1 on potassium currents, expressed in CX3CR1-Green Fluorescent Protein labeled microglia in transgenic mice. The results showed that CXCL1 hyperpolarized the cells by enhancing inward rectifying potassium currents and increasing the membrane area, suggesting an activating effect on microglia.
Collapse
Affiliation(s)
- Alexandru-Florian Deftu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Violeta Ristoiu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Marc Rene Suter
- Pain Center, Department of Anesthesiology, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland
| |
Collapse
|
36
|
Liu W, Zhu M, Yu Z, Yin D, Lu F, Pu Y, Zhao C, He C, Cao L. Therapeutic effects of diosgenin in experimental autoimmune encephalomyelitis. J Neuroimmunol 2017; 313:152-160. [PMID: 29132838 DOI: 10.1016/j.jneuroim.2017.10.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 10/26/2017] [Accepted: 10/30/2017] [Indexed: 01/10/2023]
Abstract
Multiple sclerosis (MS) is a chronic autoimmune demyelinating disease of the central nervous system. Currently, there is no drug available to cure this kind of disease. Diosgenin is a plant-derived steroid saponin. A previous study in our lab revealed that diosgenin can promote oligodendrocyte progenitor cell differentiation and accelerate remyelination. In the present study, we found that diosgenin dose-dependently alleviated the progression of experimental autoimmune encephalomyelitis with reduced central nervous system inflammation and demyelination. We also found that diosgenin treatment can significantly inhibit the activation of microglia and macrophages, suppress CD4+ T cell proliferation and hinder Th1/Th17 cell differentiation. Therefore, we suggested that diosgenin may be a potential therapeutic drug for inflammatory demyelinating diseases, such as MS.
Collapse
MESH Headings
- Animals
- Anti-Inflammatory Agents/therapeutic use
- Antigens, CD/metabolism
- Diosgenin/therapeutic use
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Encephalitis/drug therapy
- Encephalitis/etiology
- Encephalomyelitis, Autoimmune, Experimental/complications
- Encephalomyelitis, Autoimmune, Experimental/drug therapy
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Female
- Leukocytes, Mononuclear/drug effects
- Leukocytes, Mononuclear/pathology
- Mice
- Mice, Inbred C57BL
- Microglia/drug effects
- Statistics, Nonparametric
- Treatment Outcome
Collapse
Affiliation(s)
- Weili Liu
- Institute of Health Sciences, Anhui University, Hefei 230601, China; Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of the Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China
| | - Mei Zhu
- Institute of Health Sciences, Anhui University, Hefei 230601, China; Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of the Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China
| | - Zhongwang Yu
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of the Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China
| | - Dou Yin
- Institute of Health Sciences, Anhui University, Hefei 230601, China; Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of the Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China
| | - Fengfeng Lu
- Institute of Health Sciences, Anhui University, Hefei 230601, China; Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of the Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China
| | - Yingyan Pu
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of the Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China
| | - Chao Zhao
- Wellcome Trust-Medical Research Council Stem Cell Institute, University of Cambridge, Cambridge CB2 0AH, England, UK
| | - Cheng He
- Institute of Health Sciences, Anhui University, Hefei 230601, China; Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of the Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China.
| | - Li Cao
- Institute of Neuroscience, Key Laboratory of Molecular Neurobiology of the Ministry of Education and the Collaborative Innovation Center for Brain Science, Second Military Medical University, Shanghai 200433, China.
| |
Collapse
|
37
|
Pérez-García MT, Cidad P, López-López JR. The secret life of ion channels: Kv1.3 potassium channels and proliferation. Am J Physiol Cell Physiol 2017; 314:C27-C42. [PMID: 28931540 DOI: 10.1152/ajpcell.00136.2017] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Kv1.3 channels are involved in the switch to proliferation of normally quiescent cells, being implicated in the control of cell cycle in many different cell types and in many different ways. They modulate membrane potential controlling K+ fluxes, sense changes in potential, and interact with many signaling molecules through their intracellular domains. From a mechanistic point of view, we can describe the role of Kv1.3 channels in proliferation with at least three different models. In the "membrane potential model," membrane hyperpolarization resulting from Kv1.3 activation provides the driving force for Ca2+ influx required to activate Ca2+-dependent transcription. This model explains most of the data obtained from several cells from the immune system. In the "voltage sensor model," Kv1.3 channels serve mainly as sensors that transduce electrical signals into biochemical cascades, independently of their effect on membrane potential. Kv1.3-dependent proliferation of vascular smooth muscle cells (VSMCs) could fit this model. Finally, in the "channelosome balance model," the master switch determining proliferation may be related to the control of the Kv1.3 to Kv1.5 ratio, as described in glial cells and also in VSMCs. Since the three mechanisms cannot function independently, these models are obviously not exclusive. Nevertheless, they could be exploited differentially in different cells and tissues. This large functional flexibility of Kv1.3 channels surely gives a new perspective on their functions beyond their elementary role as ion channels, although a conclusive picture of the mechanisms involved in Kv1.3 signaling to proliferation is yet to be reached.
Collapse
Affiliation(s)
- M Teresa Pérez-García
- Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular, Universidad de Valladolid y Consejo Superior de Investigaciones Científicas , Valladolid , Spain
| | - Pilar Cidad
- Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular, Universidad de Valladolid y Consejo Superior de Investigaciones Científicas , Valladolid , Spain
| | - José R López-López
- Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular, Universidad de Valladolid y Consejo Superior de Investigaciones Científicas , Valladolid , Spain
| |
Collapse
|
38
|
Xu E, Liu J, Liu H, Wang X, Xiong H. Role of microglia in methamphetamine-induced neurotoxicity. INTERNATIONAL JOURNAL OF PHYSIOLOGY, PATHOPHYSIOLOGY AND PHARMACOLOGY 2017; 9:84-100. [PMID: 28694920 PMCID: PMC5498881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 05/27/2017] [Indexed: 06/07/2023]
Abstract
Methamphetamine (Meth) is an addictive psychostimulant widely abused around the world. The chronic use of Meth produces neurotoxicity featured by dopaminergic terminal damage and microgliosis, resulting in serious neurological and behavioral consequences. Ample evidence indicate that Meth causes microglial activation and resultant secretion of pro-inflammatory molecules leading to neural injury. However, the mechanisms underlying Meth-induced microglial activation remain to be determined. In this review, we attempt to address the effects of Meth on human immunodeficiency virus (HIV)-associated microglia activation both in vitro and in-vivo. Meth abuse not only increases HIV transmission but also exacerbates progression of HIV-associated neurocognitive disorders (HAND) through activation of microglia. In addition, the therapeutic potential of anti-inflammatory drugs on ameliorating Meth-induced microglia activation and resultant neuronal injury is discussed.
Collapse
Affiliation(s)
- Enquan Xu
- Neurophysiology Laboratory, Departments of Pharmacology and Experimental Neuroscience, University of Nebraska Medical CenterOmaha 68198-5880, NE, USA
| | - Jianuo Liu
- Neurophysiology Laboratory, Departments of Pharmacology and Experimental Neuroscience, University of Nebraska Medical CenterOmaha 68198-5880, NE, USA
| | - Han Liu
- Neurophysiology Laboratory, Departments of Pharmacology and Experimental Neuroscience, University of Nebraska Medical CenterOmaha 68198-5880, NE, USA
| | - Xiaobei Wang
- College of Pharmacy, University of Nebraska Medical CenterOmaha 68198-6125, NE, USA
| | - Huangui Xiong
- Neurophysiology Laboratory, Departments of Pharmacology and Experimental Neuroscience, University of Nebraska Medical CenterOmaha 68198-5880, NE, USA
| |
Collapse
|
39
|
Martínez-Moreno M, Batlle M, Ortega FJ, Gimeno-Bayón J, Andrade C, Mahy N, Rodríguez MJ. Diazoxide enhances excitotoxicity-induced neurogenesis and attenuates neurodegeneration in the rat non-neurogenic hippocampus. Neuroscience 2016; 333:229-43. [PMID: 27471195 DOI: 10.1016/j.neuroscience.2016.07.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 07/18/2016] [Accepted: 07/19/2016] [Indexed: 12/13/2022]
Abstract
Diazoxide, a well-known mitochondrial KATP channel opener with neuroprotective effects, has been proposed for the effective and safe treatment of neuroinflammation. To test whether diazoxide affects the neurogenesis associated with excitotoxicity in brain injury, we induced lesions by injecting excitotoxic N-methyl-d-aspartate (NMDA) into the rat hippocampus and analyzed the effects of a daily oral administration of diazoxide on the induced lesion. Specific glial and neuronal staining showed that NMDA elicited a strong glial reaction associated with progressive neuronal loss in the whole hippocampal formation. Doublecortin immunohistochemistry and bromo-deoxyuridine (BrdU)-NeuN double immunohistochemistry revealed that NMDA also induced cell proliferation and neurogenesis in the lesioned non-neurogenic hippocampus. Furthermore, glial fibrillary acidic protein (GFAP)-positive cells in the injured hippocampus expressed transcription factor Sp8 indicating that the excitotoxic lesion elicited the migration of progenitors from the subventricular zone and/or the reprograming of reactive astrocytes. Diazoxide treatment attenuated the NMDA-induced hippocampal injury in rats, as demonstrated by decreases in the size of the lesion, neuronal loss and microglial reaction. Diazoxide also increased the number of BrdU/NeuN double-stained cells and elevated the number of Sp8-positive cells in the lesioned hippocampus. These results indicate a role for KATP channel activation in regulating excitotoxicity-induced neurogenesis in brain injury.
Collapse
Affiliation(s)
- M Martínez-Moreno
- Departament de Biomedicina, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Institut de Neurociències, Universitat de Barcelona and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
| | - M Batlle
- Departament de Biomedicina, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Institut de Neurociències, Universitat de Barcelona and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
| | - F J Ortega
- Departament de Biomedicina, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Institut de Neurociències, Universitat de Barcelona and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
| | - J Gimeno-Bayón
- Departament de Biomedicina, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Institut de Neurociències, Universitat de Barcelona and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
| | - C Andrade
- Departament de Biomedicina, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Institut de Neurociències, Universitat de Barcelona and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
| | - N Mahy
- Departament de Biomedicina, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Institut de Neurociències, Universitat de Barcelona and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
| | - M J Rodríguez
- Departament de Biomedicina, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Institut de Neurociències, Universitat de Barcelona and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain.
| |
Collapse
|
40
|
Kurland DB, Gerzanich V, Karimy JK, Woo SK, Vennekens R, Freichel M, Nilius B, Bryan J, Simard JM. The Sur1-Trpm4 channel regulates NOS2 transcription in TLR4-activated microglia. J Neuroinflammation 2016; 13:130. [PMID: 27246103 PMCID: PMC4888589 DOI: 10.1186/s12974-016-0599-2] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 05/24/2016] [Indexed: 12/12/2022] Open
Abstract
Background Harmful effects of activated microglia are due, in part, to the formation of peroxynitrite radicals, which is attributable to the upregulation of inducible nitric oxide (NO) synthase (NOS2). Because NOS2 expression is determined by Ca2+-sensitive calcineurin (CN) dephosphorylating nuclear factor of activated T cells (NFAT), and because Sur1-Trpm4 channels are crucial for regulating Ca2+ influx, we hypothesized that, in activated microglia, Sur1-Trpm4 channels play a central role in regulating CN/NFAT and downstream target genes such as Nos2. Methods We studied microglia in vivo and in primary culture from adult rats, and from wild type, Abcc8−/− and Trpm4−/− mice, and immortalized N9 microglia, following activation of Toll-like receptor 4 (TLR4) by lipopolysaccharide (LPS), using in situ hybridization, immunohistochemistry, co-immunoprecipitation, immunoblot, qPCR, patch clamp electrophysiology, calcium imaging, the Griess assay, and chromatin immunoprecipitation. Results In microglia in vivo and in vitro, LPS activation of TLR4 led to de novo upregulation of Sur1-Trpm4 channels and CN/NFAT-dependent upregulation of Nos2 mRNA, NOS2 protein, and NO. Pharmacological inhibition of Sur1 (glibenclamide), Trpm4 (9-phenanthrol), or gene silencing of Abcc8 or Trpm4 reduced Nos2 upregulation. Inhibiting Sur1-Trpm4 increased the intracellular calcium concentration ([Ca2+]i), as expected, but also decreased NFAT nuclear translocation. The increase in [Ca2+]i induced by inhibiting or silencing Sur1-Trpm4 resulted in phosphorylation of Ca2+/calmodulin protein kinase II and of CN, consistent with reduced nuclear translocation of NFAT. The regulation of NFAT by Sur1-Trpm4 was confirmed using chromatin immunoprecipitation. Conclusions Sur1-Trpm4 constitutes a novel mechanism by which TLR4-activated microglia regulate pro-inflammatory, Ca2+-sensitive gene expression, including Nos2.
Collapse
Affiliation(s)
- David B Kurland
- Department of Neurosurgery, University of Maryland School of Medicine, 22 S. Greene St., Suite S12D, Baltimore, MD, 21201-1595, USA. .,Neurosurgery Research Laboratories, 10 S. Pine St, Baltimore, MD, 21201-1595, USA.
| | - Volodymyr Gerzanich
- Department of Neurosurgery, University of Maryland School of Medicine, 22 S. Greene St., Suite S12D, Baltimore, MD, 21201-1595, USA
| | - Jason K Karimy
- Department of Neurosurgery, University of Maryland School of Medicine, 22 S. Greene St., Suite S12D, Baltimore, MD, 21201-1595, USA
| | - Seung Kyoon Woo
- Department of Neurosurgery, University of Maryland School of Medicine, 22 S. Greene St., Suite S12D, Baltimore, MD, 21201-1595, USA
| | - Rudi Vennekens
- Department Cell Molecular Medicine, Laboratory Ion Channel Research, Campus Gasthuisberg, Herestraat 49-Bus 802, Leuven, 3000, Belgium
| | - Marc Freichel
- Pharmakologisches Institut, Universität Heidelberg, Im Neuenheimer Feld 366, Heidelberg, 69120, Germany
| | - Bernd Nilius
- Department Cell Molecular Medicine, Laboratory Ion Channel Research, Campus Gasthuisberg, Herestraat 49-Bus 802, Leuven, 3000, Belgium
| | - Joseph Bryan
- Pacific Northwest Diabetes Research Institute, 720 Broadway, Seattle, WA, 98122, USA
| | - J Marc Simard
- Department of Neurosurgery, University of Maryland School of Medicine, 22 S. Greene St., Suite S12D, Baltimore, MD, 21201-1595, USA. .,Department of Pathology, University of Maryland School of Medicine, Baltimore, MD, USA. .,Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA.
| |
Collapse
|
41
|
Siddiqui TA, Lively S, Schlichter LC. Complex molecular and functional outcomes of single versus sequential cytokine stimulation of rat microglia. J Neuroinflammation 2016; 13:66. [PMID: 27009332 PMCID: PMC4806433 DOI: 10.1186/s12974-016-0531-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 03/16/2016] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Microglia are the "professional" phagocytes of the CNS. Phagocytosis is crucial for normal CNS development and maintenance, but it can be either beneficial or detrimental after injury or disease. For instance, white matter damage releases myelin debris that must be cleared by microglia in order for re-myelination to occur. However, phagocytosis can also produce damaging reactive oxygen species (ROS). Furthermore, microglia can acquire pro-inflammatory (M1) or anti-inflammatory (M2) activation states that affect cell functions. Although microglia are exposed to a changing cytokine environment after injury or disease, little is known about the molecular and functional consequences. Therefore, we applied several microglial activation paradigms, with or without myelin debris. We assessed (i) gene expression changes reflecting microglial activation and inflammatory states, and receptors and enzymes related to phagocytosis and ROS production, (ii) myelin phagocytosis and production of ROS, and (iii) expression and contributions of several ion channels that are considered potential targets for regulating microglial behavior. METHODS Primary rat microglia were exposed to cytokines, individually or sequentially. First, responses to individual M1 or M2 stimuli were compared: IFN-γ plus TNF-α ("I + T"; M1 activation), interleukin-4 (M2a/alternative activation), and interleukin-10 (M2c/acquired deactivation). Second, sequential cytokine addition was used to assess microglia repolarization and cell functions. The paradigms were M2a→M1, M2c→M1, M1→M2a, and M1→M2c. RESULTS M1 stimulation increased pro-inflammatory genes, phagocytosis, and ROS, as well as expression of Kv1.3, KCa3.1, and Kir2.1 channels. M2a stimulation increased anti-inflammatory genes, ROS production, and Kv1.3 and KCa3.1 expression. Myelin phagocytosis enhanced the M1 profile and dampened the M2a profile, and both phagocytosis and ROS production were dependent on NOX enzymes and Kir2.1 and CRAC channels. Importantly, microglia showed some capacity for re-polarization between M1 and M2a states, based on gene expression changes, myelin phagocytosis, and ROS production. CONCLUSIONS In response to polarizing and re-polarizing cytokine treatments, microglia display complex changes in gene transcription profiles, phagocytic capacity, NOX-mediated ROS production, and in ion channels involved in microglial activation. Because these changes might affect microglia-mediated CNS inflammation, they should be considered in future experimental, pre-clinical studies.
Collapse
Affiliation(s)
- Tamjeed A Siddiqui
- Genes and Development Division, Krembil Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada.,Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Starlee Lively
- Genes and Development Division, Krembil Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada
| | - Lyanne C Schlichter
- Genes and Development Division, Krembil Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada. .,Department of Physiology, University of Toronto, Toronto, Ontario, Canada. .,Krembil Discovery Tower, Krembil Research Institute, Room 7KD-417, 60 Leonard Street, Toronto, Ontario, M5T 2S8, Canada.
| |
Collapse
|