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Leavy A, Phelan J, Jimenez-Mateos EM. Contribution of microglia to the epileptiform activity that results from neonatal hypoxia. Neuropharmacology 2024; 253:109968. [PMID: 38692453 DOI: 10.1016/j.neuropharm.2024.109968] [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: 02/22/2024] [Revised: 04/13/2024] [Accepted: 04/22/2024] [Indexed: 05/03/2024]
Abstract
Microglia are described as the immune cells of the brain, their immune properties have been extensively studied since first described, however, their neural functions have only been explored over the last decade. Microglia have an important role in maintaining homeostasis in the central nervous system by surveying their surroundings to detect pathogens or damage cells. While these are the classical functions described for microglia, more recently their neural functions have been defined; they are critical to the maturation of neurons during embryonic and postnatal development, phagocytic microglia remove excess synapses during development, a process called synaptic pruning, which is important to overall neural maturation. Furthermore, microglia can respond to neuronal activity and, together with astrocytes, can regulate neural activity, contributing to the equilibrium between excitation and inhibition through a feedback loop. Hypoxia at birth is a serious neurological condition that disrupts normal brain function resulting in seizures and epilepsy later in life. Evidence has shown that microglia may contribute to this hyperexcitability after neonatal hypoxia. This review will summarize the existing data on the role of microglia in the pathogenesis of neonatal hypoxia and the plausible mechanisms that contribute to the development of hyperexcitability after hypoxia in neonates. This article is part of the Special Issue on "Microglia".
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Affiliation(s)
- Aisling Leavy
- Discipline of Physiology, School of Medicine, Trinity College Dublin, The University of Dublin, Dublin, Ireland
| | - Jessie Phelan
- Discipline of Physiology, School of Medicine, Trinity College Dublin, The University of Dublin, Dublin, Ireland
| | - Eva M Jimenez-Mateos
- Discipline of Physiology, School of Medicine, Trinity College Dublin, The University of Dublin, Dublin, Ireland.
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2
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Bhandare AM, Dale N, Huckstepp RTR. Imaging Single-Cell Ca 2+ Dynamics of Brainstem Neurons and Glia in Freely Behaving Mice. Bio Protoc 2024; 14:e4973. [PMID: 38737784 PMCID: PMC11082788 DOI: 10.21769/bioprotoc.4973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 03/13/2024] [Accepted: 03/14/2024] [Indexed: 05/14/2024] Open
Abstract
In vivo brain imaging, using a combination of genetically encoded Ca2+ indicators and gradient refractive index (GRIN) lens, is a transformative technology that has become an increasingly potent research tool over the last decade. It allows direct visualisation of the dynamic cellular activity of deep brain neurons and glia in conscious animals and avoids the effect of anaesthesia on the network. This technique provides a step change in brain imaging where fibre photometry combines the whole ensemble of cellular activity, and multiphoton microscopy is limited to imaging superficial brain structures either under anaesthesia or in head-restrained conditions. We have refined the intravital imaging technique to image deep brain nuclei in the ventral medulla oblongata, one of the most difficult brain structures to image due to the movement of brainstem structures outside the cranial cavity during free behaviour (head and neck movement), whose targeting requires GRIN lens insertion through the cerebellum-a key structure for balance and movement. Our protocol refines the implantation method of GRIN lenses, giving the best possible approach to image deep extracranial brainstem structures in awake rodents with improved cell rejection/acceptance criteria during analysis. We have recently reported this method for imaging the activity of retrotrapezoid nucleus and raphe neurons to outline their chemosensitive characteristics. This revised method paves the way to image challenging brainstem structures to investigate their role in complex behaviours such as breathing, circulation, sleep, digestion, and swallowing, and could be extended to image and study the role of cerebellum in balance, movement, motor learning, and beyond. Key features • We developed a protocol that allows imaging from brainstem neurons and glia in freely behaving rodents. • Our refined method of GRIN lenses implantation and cell sorting approach gives the highest number of cells with the least postoperative complications. • The revised deep brainstem imaging method paves way to understand complex behaviours such as cardiorespiratory regulation, sleep, swallowing, and digestion. • Our protocol can be implemented to image cerebellar structures to understand their role in key functions such as balance, movement, motor learning, and more.
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Affiliation(s)
| | - Nicholas Dale
- School of Life Sciences, University of Warwick, Coventry, UK
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3
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Pan S, Bruun DA, Lein PJ, Chen CY. Cardiovascular responses of adult male Sprague-Dawley rats following acute organophosphate intoxication and post-exposure treatment with midazolam with or without allopregnanolone. Arch Toxicol 2024; 98:1177-1189. [PMID: 38305864 PMCID: PMC10944447 DOI: 10.1007/s00204-023-03679-x] [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: 09/11/2023] [Accepted: 12/20/2023] [Indexed: 02/03/2024]
Abstract
Recent experimental evidence suggests combined treatment with midazolam and allopregnanolone is more effective than midazolam alone in terminating seizures triggered by acute organophosphate (OP) intoxication. However, there are concerns that combined midazolam and allopregnanolone increases risk of adverse cardiovascular events. To address this, we used telemetry devices to record cardiovascular responses in adult male Sprague-Dawley rats acutely intoxicated with diisopropylfluorophosphate (DFP). Animals were administered DFP (4 mg/kg, sc), followed immediately by atropine (2 mg/kg, i.m.) and 2-PAM (25 mg/kg, i.m.). At 40 min post-exposure, a subset of animals received midazolam (0.65 mg/kg, im); at 50 min, these rats received a second dose of midazolam or allopregnanolone (12 mg/kg, im). DFP significantly increased blood pressure by ~ 80 mmHg and pulse pressure by ~ 34 mmHg that peaked within 12 min. DFP also increased core temperature by ~ 3.5 °C and heart rate by ~ 250 bpm that peaked at ~ 2 h. Heart rate variability (HRV), an index of autonomic function, was reduced by ~ 80%. All acute (within 15 min of exposure) and two-thirds of delayed (hours after exposure) mortalities were associated with non-ventricular cardiac events within 10 min of cardiovascular collapse, suggesting that non-ventricular events should be closely monitored in OP-poisoned patients. Compared to rats that survived DFP intoxication without treatment, midazolam significantly improved recovery of cardiovascular parameters and HRV, an effect enhanced by allopregnanolone. These data demonstrate that midazolam improved recovery of cardiovascular and autonomic function and that the combination of midazolam and allopregnanolone may be a better therapeutic strategy than midazolam alone.
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Affiliation(s)
- Shiyue Pan
- Department of Pharmacology, Davis, School of Medicine, University of California, Davis, CA, USA
| | - Donald A Bruun
- Department of Molecular Biosciences, Davis, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Pamela J Lein
- Department of Molecular Biosciences, Davis, School of Veterinary Medicine, University of California, Davis, CA, USA
- Davis, School of Medicine, MIND Institute, University of California, Sacramento, CA, USA
| | - Chao-Yin Chen
- Department of Pharmacology, Davis, School of Medicine, University of California, Davis, CA, USA.
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4
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Bhandare AM, Dale N. Neural correlate of reduced respiratory chemosensitivity during chronic epilepsy. Front Cell Neurosci 2023; 17:1288600. [PMID: 38193031 PMCID: PMC10773801 DOI: 10.3389/fncel.2023.1288600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 11/27/2023] [Indexed: 01/10/2024] Open
Abstract
While central autonomic, cardiac, and/or respiratory dysfunction underlies sudden unexpected death in epilepsy (SUDEP), the specific neural mechanisms that lead to SUDEP remain to be determined. In this study, we took advantage of single-cell neuronal Ca2+ imaging and intrahippocampal kainic acid (KA)-induced chronic epilepsy in mice to investigate progressive changes in key cardiorespiratory brainstem circuits during chronic epilepsy. Weeks after induction of status epilepticus (SE), when mice were experiencing recurrent spontaneous seizures (chronic epilepsy), we observed that the adaptive ventilatory responses to hypercapnia were reduced for 5 weeks after SE induction with its partial recovery at week 7. These changes were paralleled by alterations in the chemosensory responses of neurons in the retrotrapezoid nucleus (RTN). Neurons that displayed adapting responses to hypercapnia were less prevalent and exhibited smaller responses over weeks 3-5, whereas neurons that displayed graded responses to hypercapnia became more prevalent by week 7. Over the same period, chemosensory responses of the presympathetic rostral ventrolateral medullary (RVLM) neurons showed no change. Mice with chronic epilepsy showed enhanced sensitivity to seizures, which invade the RTN and possibly put the chemosensory circuits at further risk of impairment. Our findings establish a dysfunctional breathing phenotype with its RTN neuronal correlate in mice with chronic epilepsy and suggest that the assessment of respiratory chemosensitivity may have the potential for identifying people at risk of SUDEP.
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Affiliation(s)
- Amol M. Bhandare
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
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5
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Reconnoitering the transformative journey of minocycline from an antibiotic to an antiepileptic drug. Life Sci 2022; 293:120346. [PMID: 35065989 DOI: 10.1016/j.lfs.2022.120346] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 01/04/2022] [Accepted: 01/16/2022] [Indexed: 12/20/2022]
Abstract
Minocycline, a second-generation tetracycline antibiotic is being widely tested in animals as well as clinical settings for the management of multiple neurological disorders. The drug has shown to exert protective action in a multitude of neurological disorders including spinal-cord injury, stroke, multiple sclerosis, amyotrophic lateral sclerosis, Huntington's disease, and Parkinson's disease. Being highly lipophilic, minocycline easily penetrates the blood brain barrier and is claimed to have excellent oral absorption (~100% bioavailability). Minocycline possesses anti-inflammatory, immunomodulatory, and anti-apoptotic properties, thereby supporting its use in treating neurological disorders. The article henceforth reviews all the recent advances in the transformation of this antibiotic into a potential antiepileptic/antiepileptogenic agent. The article also gives an account of all the clinical trials undertaken till now validating the antiepileptic potential of minocycline. Based on the reported studies, minocycline seems to be an important molecule for treating epilepsy. However, the practical therapeutic implementations of this molecule require extensive mechanism-based in-vitro (cell culture) and in-vivo (animal models) studies followed by its testing in randomized, placebo controlled and double-blind clinical trials in large population as well as in different form of epilepsies.
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6
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Acute and chronic cardiorespiratory consequences of focal intrahippocampal administration of seizure-inducing agents. Implications for SUDEP. Auton Neurosci 2021; 235:102864. [PMID: 34428716 DOI: 10.1016/j.autneu.2021.102864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 07/02/2021] [Accepted: 07/26/2021] [Indexed: 11/20/2022]
Abstract
The risk factors for SUDEP are undoubtedly heterogenous but the main factor is the frequency of generalized tonic-clonic seizures with apnoea and/or cardiac abnormalities likely precipitating the lethal event. By its very nature modelling SUDEP experimentally is challenging, yet insights into the nature of the lethal event and precipitating factors are vital in order to understand and prevent fatalities. Acute animal models, which induce status epilepticus (SE), can be used to help understand pathophysiological processes during and following seizures, which sometimes lead to death. The most commonly used method to induce seizures and status epilepticus is systemic administration of an ictogenic agent. Microinjection of such agents into restricted regions within the brain induces a more localised epileptic focus and circumvents the risk of direct actions on cardiorespiratory control centres. Both approaches have revealed substantial cardiovascular and respiratory consequences, including death as a result of apnoea, which may be of central origin, obstructive due to laryngospasm or, at least in genetically modified mice, a result of spreading depolarisation to medullary respiratory control centres. SUDEP is by definition a result of epilepsy, which in turn is diagnosed on the basis of two or more unprovoked seizures. The incidence of tonic-clonic seizures is the main risk factor, raising the possibility that repeated seizures cause cumulative pathological and/or pathophysiological changes that contribute to the risk of SUDEP. Chronic experimental models, which induce repeated seizures that in some cases lead to death, do show progressive development of pathophysiological changes in the myocardium, e.g. prolongation of QT the interval of the ECG or, over longer periods, ventricular hypertrophy. However, the currently available evidence indicates that seizure-related deaths are primarily due to apnoeas, but cardiac factors, particularly cumulative cardiac pathophysiologies due to repeated seizures, are potential contributing factors.
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7
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Díaz HS, Toledo C, Andrade DC, Marcus NJ, Del Rio R. Neuroinflammation in heart failure: new insights for an old disease. J Physiol 2020; 598:33-59. [PMID: 31671478 DOI: 10.1113/jp278864] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 09/09/2019] [Indexed: 08/25/2023] Open
Abstract
Heart failure (HF) is a complex clinical syndrome affecting roughly 26 million people worldwide. Increased sympathetic drive is a hallmark of HF and is associated with disease progression and higher mortality risk. Several mechanisms contribute to enhanced sympathetic activity in HF, but these pathways are still incompletely understood. Previous work suggests that inflammation and activation of the renin-angiotensin system (RAS) increases sympathetic drive. Importantly, chronic inflammation in several brain regions is commonly observed in aged populations, and a growing body of evidence suggests neuroinflammation plays a crucial role in HF. In animal models of HF, central inhibition of RAS and pro-inflammatory cytokines normalizes sympathetic drive and improves cardiac function. The precise molecular and cellular mechanisms that lead to neuroinflammation and its effect on HF progression remain undetermined. This review summarizes the most recent advances in the field of neuroinflammation and autonomic control in HF. In addition, it focuses on cellular and molecular mediators of neuroinflammation in HF and in particular on brain regions involved in sympathetic control. Finally, we will comment on what is known about neuroinflammation in the context of preserved vs. reduced ejection fraction HF.
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Affiliation(s)
- Hugo S Díaz
- Laboratory of Cardiorespiratory Control, Department of Physiology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Camilo Toledo
- Laboratory of Cardiorespiratory Control, Department of Physiology, Pontificia Universidad Católica de Chile, Santiago, Chile
- Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile
| | - David C Andrade
- Laboratory of Cardiorespiratory Control, Department of Physiology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Noah J Marcus
- Department of Physiology and Pharmacology, Des Moines University, Des Moines, IA, USA
| | - Rodrigo Del Rio
- Laboratory of Cardiorespiratory Control, Department of Physiology, Pontificia Universidad Católica de Chile, Santiago, Chile
- Centro de Envejecimiento y Regeneración (CARE-UC), Pontificia Universidad Católica de Chile, Santiago, Chile
- Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile
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8
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Jefferys JGR, Arafat MA, Irazoqui PP, Lovick TA. Brainstem activity, apnea, and death during seizures induced by intrahippocampal kainic acid in anaesthetized rats. Epilepsia 2019; 60:2346-2358. [PMID: 31705531 DOI: 10.1111/epi.16374] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 09/25/2019] [Accepted: 10/04/2019] [Indexed: 11/30/2022]
Affiliation(s)
- John G. R. Jefferys
- Weldon School of Biomedical Engineering Purdue University West Lafayette IN USA
- Department of Pharmacology Oxford University Oxford UK
| | - Muhammad A. Arafat
- Weldon School of Biomedical Engineering Purdue University West Lafayette IN USA
- Department of Electrical and Computer Engineering Purdue University West Lafayette IN USA
| | - Pedro P. Irazoqui
- Weldon School of Biomedical Engineering Purdue University West Lafayette IN USA
- Department of Electrical and Computer Engineering Purdue University West Lafayette IN USA
| | - Thelma A. Lovick
- Weldon School of Biomedical Engineering Purdue University West Lafayette IN USA
- School of Physiology, Pharmacology and Neuroscience University of Bristol Bristol UK
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9
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Li R, Buchanan GF. Scurrying to Understand Sudden Expected Death in Epilepsy: Insights From Animal Models. Epilepsy Curr 2019; 19:390-396. [PMID: 31526023 PMCID: PMC6891182 DOI: 10.1177/1535759719874787] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Sudden unexpected death in epilepsy (SUDEP) is the leading cause of death in patients with refractory epilepsy, accounting for up to 17% of deaths in patients with epilepsy. The pathophysiology of SUDEP has remained unclear, largely because it is unpredictable and commonly unwitnessed. This poses a great challenge to studies in patients. Recently, there has been an increase in animal studies to try to better understand the pathophysiology of SUDEP. In this current review, we focus on developments through seizure-induced death models and the preventative strategies they may reveal.
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Affiliation(s)
- Rui Li
- Department of Neurology, Carver College of Medicine, University of Iowa, IA, USA
- Iowa Neuroscience Institute, Carver College of Medicine, University of Iowa, IA, USA
| | - Gordon F. Buchanan
- Department of Neurology, Carver College of Medicine, University of Iowa, IA, USA
- Iowa Neuroscience Institute, Carver College of Medicine, University of Iowa, IA, USA
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10
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Farnham MMJ, Tallapragada VJ, O'Connor ET, Nedoboy PE, Dempsey B, Mohammed S, Fong AY, Lung MSY, Derakhshan F, Wilson RJA, Pilowsky PM. PACAP-PAC1 Receptor Activation Is Necessary for the Sympathetic Response to Acute Intermittent Hypoxia. Front Neurosci 2019; 13:881. [PMID: 31496933 PMCID: PMC6712064 DOI: 10.3389/fnins.2019.00881] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 08/05/2019] [Indexed: 01/29/2023] Open
Abstract
Repetitive hypoxia is a key feature of obstructive sleep apnoea (OSA), a condition characterized by intermittent airways obstruction. Patients with OSA present with persistent increases in sympathetic activity and commonly develop hypertension. The objectives of this study were to determine if the persistent increases in sympathetic nerve activity, known to be induced by acute intermittent hypoxia (AIH), are mediated through activation of the pituitary adenylate cyclase activating polypeptide (PACAP) signaling system. Here, we show that the excitatory neuropeptide PACAP, acting in the spinal cord, is important for generating the sympathetic response seen following AIH. Using PACAP receptor knockout mice, and pharmacological agents in Sprague Dawley rats, we measured blood pressure, heart rate, pH, PaCO2, and splanchnic sympathetic nerve activity, under anaesthesia, to demonstrate that the sympathetic response to AIH is mediated via the PAC1 receptor, in a cAMP-dependent manner. We also report that both intermittent microinjection of glutamate into the rostroventrolateral medulla (RVLM) and intermittent infusion of a sub-threshold dose of PACAP into the subarachnoid space can mimic the sympathetic response to AIH. All the sympathetic responses are independent of blood pressure, pH or PaCO2 changes. Our results show that in AIH, PACAP signaling in the spinal cord helps drive persistent increases in sympathetic nerve activity. This mechanism may be a precursor to the development of hypertension in conditions of chronic intermittent hypoxia, such as OSA.
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Affiliation(s)
- Melissa M J Farnham
- The Heart Research Institute, Newtown, NSW, Australia.,Faculty of Medicine, Macquarie University, North Ryde, NSW, Australia.,Department of Physiology, Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
| | | | - Edward T O'Connor
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Polina E Nedoboy
- The Heart Research Institute, Newtown, NSW, Australia.,Department of Physiology, Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
| | - Bowen Dempsey
- Faculty of Medicine, Macquarie University, North Ryde, NSW, Australia
| | - Suja Mohammed
- The Heart Research Institute, Newtown, NSW, Australia.,Faculty of Medicine, Macquarie University, North Ryde, NSW, Australia.,Department of Physiology, Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
| | - Angelina Y Fong
- Faculty of Medicine, Macquarie University, North Ryde, NSW, Australia.,Department of Physiology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, VIC, Australia
| | - Mandy S Y Lung
- Faculty of Medicine, Macquarie University, North Ryde, NSW, Australia
| | - Fatemeh Derakhshan
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Richard J A Wilson
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Paul M Pilowsky
- The Heart Research Institute, Newtown, NSW, Australia.,Department of Physiology, Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
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11
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Sun Y, Ma J, Li D, Li P, Zhou X, Li Y, He Z, Qin L, Liang L, Luo X. Interleukin-10 inhibits interleukin-1β production and inflammasome activation of microglia in epileptic seizures. J Neuroinflammation 2019; 16:66. [PMID: 30922332 PMCID: PMC6437919 DOI: 10.1186/s12974-019-1452-1] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 03/15/2019] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Microglia are important for secreting chemical mediators of inflammatory responses in the central nervous system. Interleukin (IL)-10 and IL-1β secreted by glial cells support neuronal functions, but the related mechanisms remain vague. Our goal was to demonstrate the efficacy of IL-10 in suppressing IL-1β and in inflammasome activation in mice with epileptic seizure based on an epileptic-seizure mouse model. METHODS In this study, mice in which epileptic seizures were induced by administering picrotoxin (PTX) were used as a case group, and mice injected with saline were employed as the control group. The expression of nucleic acids, cytokines, or signaling pathways was detected by reverse transcription-polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), flow cytometry, and Western blotting. RESULTS Our results demonstrated that IL-10 inhibits IL-1β production through two distinct mechanisms: (1) Treatment with lipopolysaccharides (LPS) results in IL-10 overexpression in microglia and reduced NLRP3 inflammasome activity, thus inhibiting caspase-1-related IL-1β maturation; (2) next, autocrine IL-10 was found to subsequently promote signal transducer and activator of transcription-3 (STAT-3), reducing amounts of pro-IL-1β. CONCLUSIONS Our results indicate that IL-10 is potentially effective in the treatment of inflammation encephalopathy, and suggest the potential usefulness of IL-10 for treating autoimmune or inflammatory ailments.
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Affiliation(s)
- Yi Sun
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China.,Department of Pediatric, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Jiangjun Ma
- Department of Molecular Diagnostics, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, 510060, China
| | - Dongfang Li
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China.,Department of Pediatric, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Pinggan Li
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China.,Department of Pediatric, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Xiaolin Zhou
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China.,Department of Pediatric, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Yu Li
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China.,Department of Pediatric, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Zhanwen He
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China.,Department of Pediatric, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Lijun Qin
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China.,Department of Pediatric, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Liyang Liang
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China.,Department of Pediatric, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China
| | - Xiangyang Luo
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China. .,Department of Pediatric, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, 510120, China.
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12
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Peña-Ortega F. Clinical and experimental aspects of breathing modulation by inflammation. Auton Neurosci 2018; 216:72-86. [PMID: 30503161 DOI: 10.1016/j.autneu.2018.11.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 11/06/2018] [Accepted: 11/07/2018] [Indexed: 12/19/2022]
Abstract
Neuroinflammation is produced by local or systemic alterations and mediated mainly by glia, affecting the activity of various neural circuits including those involved in breathing rhythm generation and control. Several pathological conditions, such as sudden infant death syndrome, obstructive sleep apnea and asthma exert an inflammatory influence on breathing-related circuits. Consequently breathing (both resting and ventilatory responses to physiological challenges), is affected; e.g., responses to hypoxia and hypercapnia are compromised. Moreover, inflammation can induce long-lasting changes in breathing and affect adaptive plasticity; e.g., hypoxic acclimatization or long-term facilitation. Mediators of the influences of inflammation on breathing are most likely proinflammatory molecules such as cytokines and prostaglandins. The focus of this review is to summarize the available information concerning the modulation of the breathing function by inflammation and the cellular and molecular aspects of this process. I will consider: 1) some clinical and experimental conditions in which inflammation influences breathing; 2) the variety of experimental approaches used to understand this inflammatory modulation; 3) the likely cellular and molecular mechanisms.
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Affiliation(s)
- Fernando Peña-Ortega
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, QRO 76230, México.
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13
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Pardo-Peña K, Lorea-Hernández JJ, Camacho-Hernández NP, Ordaz B, Villasana-Salazar B, Morales-Villagrán A, Peña-Ortega F. Hydrogen peroxide extracellular concentration in the ventrolateral medulla and its increase in response to hypoxia in vitro: Possible role of microglia. Brain Res 2018; 1692:87-99. [DOI: 10.1016/j.brainres.2018.04.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 03/31/2018] [Accepted: 04/25/2018] [Indexed: 12/12/2022]
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14
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Yang X, Liu N, Li X, Yang Y, Wang X, Li L, Jiang L, Gao Y, Tang H, Tang Y, Xing Y, Shang H. A Review on the Effect of Traditional Chinese Medicine Against Anthracycline-Induced Cardiac Toxicity. Front Pharmacol 2018; 9:444. [PMID: 29867456 PMCID: PMC5963334 DOI: 10.3389/fphar.2018.00444] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Accepted: 04/16/2018] [Indexed: 01/29/2023] Open
Abstract
Anthracyclines are effective agents generally used to treat solid-tumor and hematologic malignancies. The use of anthracyclines for over 40 years has improved cancer survival statistics. Nevertheless, the clinical utility of anthracyclines is limited by its dose-dependent cardiotoxicity that adversely affects 10-30% of patients. Anthracycline-induced cardiotoxicity may be classified as acute/subacute or chronic/late toxicity and leads to devastating adverse effects resulting in poor quality of life, morbidity, and premature mortality. Traditional Chinese medicine has a history of over 2,000 years, involving both unique theories and substantial experience. Several studies have investigated the potential of natural products to decrease the cardiotoxic effects of chemotherapeutic agents on healthy cells, without negatively affecting their antineoplastic activity. This article discusses the mechanism of anthracycline-induced cardiotoxicity, and summarizes traditional Chinese medicine treatment for anthracycline-induced heart failure (HF), cardiac arrhythmia, cardiomyopathy, and myocardial ischemia in recent years, in order to provide a reference for the clinical prevention and treatment of cardiac toxicity.
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Affiliation(s)
- Xinyu Yang
- Guang'anmen Hospital, Chinese Academy of Chinese Medical Sciences, Beijing, China.,Key Laboratory of Chinese Internal Medicine of the Ministry of Education, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Beijing, China
| | - Nian Liu
- Department of Cardiology, Beijing Anzhen Hospital of the Capital University of Medical Sciences, Beijing, China
| | - Xinye Li
- Guang'anmen Hospital, Chinese Academy of Chinese Medical Sciences, Beijing, China.,Key Laboratory of Chinese Internal Medicine of the Ministry of Education, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Beijing, China
| | - Yihan Yang
- Guang'anmen Hospital, Chinese Academy of Chinese Medical Sciences, Beijing, China.,Key Laboratory of Chinese Internal Medicine of the Ministry of Education, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Beijing, China
| | - Xiaofeng Wang
- Key Laboratory of Chinese Internal Medicine of the Ministry of Education, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Beijing, China
| | - Linling Li
- Department of Cardiology, Beijing Anzhen Hospital of the Capital University of Medical Sciences, Beijing, China
| | - Le Jiang
- Department of Cardiology, Beijing Anzhen Hospital of the Capital University of Medical Sciences, Beijing, China
| | - Yonghong Gao
- Key Laboratory of Chinese Internal Medicine of the Ministry of Education, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Beijing, China
| | - Hebin Tang
- Department of Pharmacology, School of Pharmaceutical Sciences, South-Central University for Nationalities, Wuhan, China
| | - Yong Tang
- Department of Pancreatic Oncology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Yanwei Xing
- Guang'anmen Hospital, Chinese Academy of Chinese Medical Sciences, Beijing, China
| | - Hongcai Shang
- Key Laboratory of Chinese Internal Medicine of the Ministry of Education, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Beijing, China
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15
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IL-6 knockout mice are protected from cocaine-induced kindling behaviors; possible involvement of JAK2/STAT3 and PACAP signalings. Food Chem Toxicol 2018; 116:249-263. [PMID: 29673861 DOI: 10.1016/j.fct.2018.04.031] [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: 02/07/2018] [Revised: 03/27/2018] [Accepted: 04/13/2018] [Indexed: 01/12/2023]
Abstract
IL-6 has been recognized as an anticonvulsant against certain neuroexcitotoxicities. We aimed to investigate on the interactive role between IL-6 and PACAP in cocaine-induced kindling behaviors. Although we found that cocaine (45 mg/kg, i.p./day x 5) significantly increased IL-6 and TNF-α expression, it resulted in a decrease in IFN-γ expression. We observed that the cocaine-induced increase in IL-6 expression was more pronounced than that in TNF-α expression. Genetic depletion of IL-6 significantly activated cocaine kindling behaviors. This phenomenon was also consistently observed in WT mice that received a neutralizing IL-6 receptor antibody. Cocaine-treated IL-6 knockout mice exhibited significantly decreased PACAP and PACAP receptor (PAC1R) mRNA levels and significantly increased TNF-α gene expression. TNF-α knockout mice were protected from cocaine kindling via an up-regulation of IL-6, phospho-JAK2/STAT3, PACAP, and PAC1R levels, which produced anti-apoptotic effects. Recombinant IL-6 protein (rIL-6, 2 μg, i.v./mouse/day x 5) also up-regulated phospho-JAK2/STAT3, PACAP, and PAC1R mRNA levels, leading to anti-apoptotic effects in IL-6 knockout mice. Consistently, AG490, a JAK2/STAT3 inhibitor, and PACAP 6-38, a PAC1 receptor antagonist, counteracted rIL-6-mediated protection. Combined, our results suggest that IL-6 gene requires up-regulation of phospho-JAK2/STAT3, PACAP, and PAC1R and down-regulation of the TNF-α gene to modulate its anticonvulsive/neuroprotective potential.
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16
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Fan Y, Jiang E, Hahka T, Chen QH, Yan J, Shan Z. Orexin A increases sympathetic nerve activity through promoting expression of proinflammatory cytokines in Sprague Dawley rats. Acta Physiol (Oxf) 2018; 222:10.1111/apha.12963. [PMID: 28872777 PMCID: PMC6064186 DOI: 10.1111/apha.12963] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2017] [Revised: 08/28/2017] [Accepted: 08/30/2017] [Indexed: 12/31/2022]
Abstract
AIM Accumulating evidence suggests that orexin signalling is involved in the regulation of blood pressure and cardiovascular function. However, the underlying mechanisms are not clear. Here, we test the hypothesis that upregulated orexin A signalling in the paraventricular nucleus (PVN) increases sympathetic nerve activity (SNA) through stimulating expression of proinflammatory cytokines (PICs). METHODS In vivo sympathetic nerve recordings were performed to test the impact of PVN orexin signalling on sympathetic outflow in Sprague Dawley (SD) rats. Real-time PCR was carried out to assess effects of central administration of orexin A on PVN PICs expression in SD rats. To test whether orexin A-induced increases in PICs were exclusively mediated by orexin receptor 1 (OX1R), OX1R-expressing PC12 (PC12-OX1R) cells were incubated with different dose of orexin A, and then, PICs mRNA and immunoreactivity were measured. RESULTS Orexin A microinjection (25 pmol) into the PVN significantly increased splanchnic SNA (93.5%) and renal SNA (83.3%) in SD rats, and these increases were attenuated by OX1R antagonist SB408124. Intracerebroventricular injection of orexin A (0.2 nmol) into SD rats increased mRNA levels of PICs including IL-1-β (2.7-fold), IL-6 (1.7-fold) and TNF-α (1.5-fold), as well as Fra1 (1.6-fold) in the PVN. Orexin A treatment in PC12-OX1R cells resulted in a dose- and time-dependent increase in the expression of PICs and Fra1, a subunit of AP1 transcriptional factor. The increase in the PICs was blocked by AP1 blocker curcumin. CONCLUSION Paraventricular nucleus orexin system activation is involved in SNA regulation maybe through triggering AP1-PICs pathway.
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Affiliation(s)
- Y Fan
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, USA
| | - E Jiang
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, USA
- College of Nursing and Health, Henan University, Kaifeng, Henan, China
| | - T Hahka
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, USA
| | - Q H Chen
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, USA
- Biotech Research Center, Michigan Technological University, Houghton, MI, USA
| | - J Yan
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Z Shan
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI, USA
- Biotech Research Center, Michigan Technological University, Houghton, MI, USA
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17
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Lasoń W, Ślusarczyk J, Regulska M, Leśkiewicz M, Basta-Kaim A. Do minocycline and other suppressors of microglia reactivity have a future in prevention or treatment of epilepsy? JOURNAL OF EPILEPTOLOGY 2017. [DOI: 10.1515/joepi-2017-0003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
SummaryIntroduction.An increasing body of evidence points to an important role of neuroinflammatory processes in the pathomechanism of epilepsy. This hypothesis is mainly supported by data showing an increase of pro-inflammatory cytokine levels and glia activation in animal models of epilepsy and in brain tissue of epileptic patients. On the other hand, less emphasis has been put on pharmacological verification of this hypothesis.Aim.The aim of this review is to summarize current knowledge on potential usefulness of microglia regulators and anti-inflammatory agents in designing antiepileptic/antiepileptogenic drugs, with the primary mechanism of action based on the inhibition of neuroinflammation.Methods.We reviewed PubMed and MEDLINE databases to select publications in the topic: epilepsy, neuroinflammation, microglia and microglia regulators with antiepileptic properties. We searched the databases up to April 2017 with no date restrictions.Review and Discussion.In the present paper, we will discuss new concepts of epileptogenesis which focus not only on changes in neurons but also take into consideration the role of activation of glial cells: microglia and astrocytes. Neuroinflammation, mainly through increased production of pro-inflammatory factors such as cytokines or chemokines, may play an important role in the development of epilepsy. Drugs regulating glial cells activation and consequently inflammatory status in the central nervous system have beneficial effects in different animal models of epilepsy as well as in clinical study in patients. The most promising compound seems to be minocycline which in some studies has been shown to possess antiepileptogenetic action. On the other hand, some antiepileptic drugs exhibit marked anti-inflammatory potency.Conclusions.There are much data to suggest that there is significant opportunity for designing new antiepileptic drugs whose primary mechanism of action entails the inhibition of neuroinflammatory processes.
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18
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Bhandare AM, Kapoor K, Powell KL, Braine E, Casillas-Espinosa P, O'Brien TJ, Farnham MM, Pilowsky PM. Inhibition of microglial activation with minocycline at the intrathecal level attenuates sympathoexcitatory and proarrhythmogenic changes in rats with chronic temporal lobe epilepsy. Neuroscience 2017; 350:23-38. [DOI: 10.1016/j.neuroscience.2017.03.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/02/2017] [Accepted: 03/07/2017] [Indexed: 12/19/2022]
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19
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Huang Q, Sun ML, Chen Y, Li XY, Wang YX. Concurrent bullatine A enhances morphine antinociception and inhibits morphine antinociceptive tolerance by indirect activation of spinal κ-opioid receptors. JOURNAL OF ETHNOPHARMACOLOGY 2017; 196:151-159. [PMID: 27989510 DOI: 10.1016/j.jep.2016.12.027] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 12/01/2016] [Accepted: 12/15/2016] [Indexed: 06/06/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Bullatine A, a C20-diterpenoid alkaloid and one of the major effective ingredients in Aconiti brachypodi Radix (Xue-shang-yi-zhi-hao), can block pain hypersensitivity in a variety of rodent models through expression of spinal microglial dynorphin A. AIM OF THE STUDY To assess the interaction between bullatine A and morphine on antinociception in acute nociception and pain hypersensitivity states, with the exogenous synthetic dynorphin A as a comparison MATERIALS AND METHODS: Spinal nerve ligation-induced neuropathic rats and naïve mice were used for assessing the acute and chronic interactions of bullatine A/dynorphin A with morphine. RESULTS Single subcutaneous injection of bullatine A or dynorphin A(1-17) did not either alter formalin- and thermally (hot-plate and water immersion tests)-induced acute nociception or potentiate morphine antinociception in naïve mice. In contrast, bullatine A dose-dependently inhibited formalin-induced tonic pain with the efficacy of 54% inhibition and the half-effective dose of 0.9mg/kg. Concurrent bullatine A additively enhanced morphine antinociception. In neuropathic rats, the antinociceptive effects of multiple bidaily intrathecal injections of bullatine A and dynorphin A remained consistent over 13 days, whereas morphine produced progressive and complete tolerance to antinociception, which was completely inhibited by concurrent bullatine A and dynorphin A. A single intrathecal injection of bullatine A and dynorphin A immediately reversed established morphine tolerance in neuropathic rats, although the blockade was a less degree in the thermally induced mouse acute nociceptive tests. The inhibitory effects of bullatine A and dynorphin A on morphine tolerance were immediately and completely attenuated by intrathecal dynorphin A antibody and/or selective κ-opioid receptor antagonist GNTI. CONCLUSION These results suggest that bullatine A produces antinociception without induction of tolerance and inhibits morphine antinociceptive tolerance, and provide pharmacological basis for concurrent bullatine A and morphine treatment for chronic pain and morphine analgesic tolerance.
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Affiliation(s)
- Qian Huang
- King's Lab, Shanghai Jiao Tong University School of Pharmacy, 800 Dongchuan Road, Shanghai 200240, China
| | - Ming-Li Sun
- King's Lab, Shanghai Jiao Tong University School of Pharmacy, 800 Dongchuan Road, Shanghai 200240, China
| | - Yuan Chen
- King's Lab, Shanghai Jiao Tong University School of Pharmacy, 800 Dongchuan Road, Shanghai 200240, China
| | - Xin-Yan Li
- King's Lab, Shanghai Jiao Tong University School of Pharmacy, 800 Dongchuan Road, Shanghai 200240, China
| | - Yong-Xiang Wang
- King's Lab, Shanghai Jiao Tong University School of Pharmacy, 800 Dongchuan Road, Shanghai 200240, China.
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20
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Neuropeptides and Microglial Activation in Inflammation, Pain, and Neurodegenerative Diseases. Mediators Inflamm 2017; 2017:5048616. [PMID: 28154473 PMCID: PMC5244030 DOI: 10.1155/2017/5048616] [Citation(s) in RCA: 143] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 11/26/2016] [Accepted: 12/05/2016] [Indexed: 12/15/2022] Open
Abstract
Microglial cells are responsible for immune surveillance within the CNS. They respond to noxious stimuli by releasing inflammatory mediators and mounting an effective inflammatory response. This is followed by release of anti-inflammatory mediators and resolution of the inflammatory response. Alterations to this delicate process may lead to tissue damage, neuroinflammation, and neurodegeneration. Chronic pain, such as inflammatory or neuropathic pain, is accompanied by neuroimmune activation, and the role of glial cells in the initiation and maintenance of chronic pain has been the subject of increasing research over the last two decades. Neuropeptides are small amino acidic molecules with the ability to regulate neuronal activity and thereby affect various functions such as thermoregulation, reproductive behavior, food and water intake, and circadian rhythms. Neuropeptides can also affect inflammatory responses and pain sensitivity by modulating the activity of glial cells. The last decade has witnessed growing interest in the study of microglial activation and its modulation by neuropeptides in the hope of developing new therapeutics for treating neurodegenerative diseases and chronic pain. This review summarizes the current literature on the way in which several neuropeptides modulate microglial activity and response to tissue damage and how this modulation may affect pain sensitivity.
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21
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Li H, Mao Y, Zhang Q, Han Q, Man Z, Zhang J, Wang X, Hu R, Zhang X, Irwin DM, Niu G, Tan H. Xinmailong mitigated epirubicin-induced cardiotoxicity via inhibiting autophagy. JOURNAL OF ETHNOPHARMACOLOGY 2016; 192:459-470. [PMID: 27586823 DOI: 10.1016/j.jep.2016.08.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 07/19/2016] [Accepted: 08/20/2016] [Indexed: 06/06/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Using insects, such as the cockroach, for the treatment of disease has a long history in traditional Chinese medicine. Xinmailong (XML) Injection, a bioactive composite extracted from Periplaneta americana (a species of cockroach), shows reasonable protective effects against cardiovascular injury and was approved for the use in the treatment of cardiac dysfunction in 2006, yet its cardio protective mechanisms remain unclear. AIM The present study aims to examine the protective effects of XML against epirubicin-induced cardiotoxicity in vivo and determine its underlying mechanisms. MATERIALS AND METHODS The chemical characteristics of XML were identified using high performance liquid chromatography (HPLC). Rats were intraperitoneally injected with epirubicin and then treated with XML for 14 days. Survival rate, echocardiography, electrocardiographic recordings and Masson staining were used to evaluate the cardioprotective activity of XML. Western blot and quantitative real time reverse transcriptase polymerase chain reaction (RT-PCR) analyses were used to investigate the molecular mechanisms underlying the actions of XML. RESULTS XML treatment significantly enhanced the survival rate of rats from epirubicin-induced heart failure. XML prevented left ventricle dilatation, improved cardiac function. Furthermore, treatment with XML also significantly inhibited the accumulation of collagen, reduced the levels of mRNA for matrix metalloproteinases-9 (Mmp9) and transforming growth factor-β 1(Tgfb1). This action of XML therefore might be responsible, at least in part, for the attenuation of cardiac fibrotic remodeling. XML inhibited autophagy as evidenced by the decreased accumulation of Beclin1 and autophagy related 7 (Atg7), which are necessary to form autophagosome structures. Protein kinase B (PKB/Akt), phosphatidylinositol 3 kinase (PI3K) and B cell lymphoma2 (Bcl2) levels were up-regulated, while significantly decreased protein levels for phosphorylated P38 and extracellular regulated protein kinases 1/2 (Erk1/2) were observed in the XML treated rats. The autophagy related results suggested that the increase in PI3K/Akt levels and inhibition of the phosphorylation of P38 MAPK and Erk1/2 contributed to the anti-autophagic activity of XML. CONCLUSIONS Our data suggest that XML may be effective for mitigating epirubicin-induced cardiomyopathy and inhibits autophagy via activating the PI3K/Akt signaling pathway and inhibiting the Erk1/2 and P38 MAPK signaling pathways.
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MESH Headings
- Animals
- Autophagy
- Cardiotonic Agents/pharmacology
- Cardiotoxicity
- Collagen/metabolism
- Disease Models, Animal
- Drugs, Chinese Herbal/pharmacology
- Epirubicin
- Extracellular Signal-Regulated MAP Kinases/metabolism
- Fibrosis
- Gene Expression Regulation
- Heart Diseases/chemically induced
- Heart Diseases/metabolism
- Heart Diseases/pathology
- Heart Diseases/prevention & control
- Hypertrophy, Left Ventricular/metabolism
- Hypertrophy, Left Ventricular/physiopathology
- Hypertrophy, Left Ventricular/prevention & control
- Male
- Matrix Metalloproteinase 9/genetics
- Matrix Metalloproteinase 9/metabolism
- Myocardium/metabolism
- Myocardium/pathology
- Phosphatidylinositol 3-Kinase/metabolism
- Proto-Oncogene Proteins c-akt/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats, Sprague-Dawley
- Signal Transduction/drug effects
- Stroke Volume/drug effects
- Time Factors
- Tissue Inhibitor of Metalloproteinases/genetics
- Tissue Inhibitor of Metalloproteinases/metabolism
- Transforming Growth Factor beta1/genetics
- Transforming Growth Factor beta1/metabolism
- Ventricular Dysfunction, Left/metabolism
- Ventricular Dysfunction, Left/physiopathology
- Ventricular Dysfunction, Left/prevention & control
- Ventricular Function, Left/drug effects
- Ventricular Remodeling/drug effects
- p38 Mitogen-Activated Protein Kinases/metabolism
- Tissue Inhibitor of Metalloproteinase-4
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Affiliation(s)
- Hui Li
- Department of Pharmacology, Peking University, Health Science Center, Beijing 100191, China
| | - Yiqing Mao
- Department of Pharmacology, Peking University, Health Science Center, Beijing 100191, China
| | - Qun Zhang
- Department of Pharmacology, Peking University, Health Science Center, Beijing 100191, China
| | - Qing Han
- Department of Pharmacology, Peking University, Health Science Center, Beijing 100191, China
| | - Zhenming Man
- Department of Pharmacology, Peking University, Health Science Center, Beijing 100191, China
| | - Jingyu Zhang
- Department of Pharmacology, Peking University, Health Science Center, Beijing 100191, China
| | - Xi Wang
- Department of Pharmacology, Peking University, Health Science Center, Beijing 100191, China
| | - Ruobi Hu
- Department of Pharmacology, Peking University, Health Science Center, Beijing 100191, China
| | - Xuehui Zhang
- Department of Pharmacology, Peking University, Health Science Center, Beijing 100191, China
| | - David M Irwin
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada M5S 1A8.
| | - Gang Niu
- Beijing N&N Genetech Company Ltd., Beijing 100082, China.
| | - Huanran Tan
- Department of Pharmacology, Peking University, Health Science Center, Beijing 100191, China.
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Bhandare AM, Kapoor K, Farnham MM, Pilowsky PM. Microglia PACAP and glutamate: Friends or foes in seizure-induced autonomic dysfunction and SUDEP? Respir Physiol Neurobiol 2016; 226:39-50. [DOI: 10.1016/j.resp.2016.01.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 01/18/2016] [Accepted: 01/21/2016] [Indexed: 12/18/2022]
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23
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Alerted microglia and the sympathetic nervous system: A novel form of microglia in the development of hypertension. Respir Physiol Neurobiol 2016; 226:51-62. [DOI: 10.1016/j.resp.2015.11.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 11/24/2015] [Accepted: 11/25/2015] [Indexed: 02/07/2023]
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24
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Microglial number is related to the number of tyrosine hydroxylase neurons in SHR and normotensive rats. Auton Neurosci 2016; 198:10-8. [PMID: 27260963 DOI: 10.1016/j.autneu.2016.05.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Revised: 05/19/2016] [Accepted: 05/20/2016] [Indexed: 01/30/2023]
Abstract
Microglia are ubiquitously distributed throughout the central nervous system (CNS) and play a critical role in the maintenance of neuronal homeostasis. Recent advances have shown that microglia, never resting cells of the CNS, continuously monitor and influence neuronal/synaptic activity levels, by communicating with neurons with the aid of their dynamic processes. The brainstem contains many catecholaminergic nuclei that are key to many aspects of brain function. This includes C1 neurons of the ventrolateral medulla that are thought to play a critical role in control of the circulation. Despite the role of catecholaminergic brainstem neurons in normal physiology, the presence of microglia that surrounds them is poorly understood. Here, we investigate the spatial distribution and morphology of microglia in catecholaminergic nuclei of the brainstem in 3 strains of rat: Sprague-Dawley (SD), Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR). Our data reveal that microglia are heterogeneously distributed within and across different strains of rats. Interestingly, intra-strain comparison of tyrosine hydroxylase-immunoreactive (TH-ir) neuronal and microglial number reveals that microglial number varies with the TH-ir neuronal number in the brainstem. Even though microglial spatial distribution varies across brainstem nuclei, microglial morphology (% area covered, number of end point processes and branch length) does not differ significantly. This work provides the first evidence that even though microglia, in their surveilling state, do not vary appreciably in their morphology across brainstem areas, they do have a heterogeneous pattern of distribution that may be influenced by their local environment.
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25
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Kapoor K, Bhandare AM, Nedoboy PE, Mohammed S, Farnham MMJ, Pilowsky PM. Dynamic changes in the relationship of microglia to cardiovascular neurons in response to increases and decreases in blood pressure. Neuroscience 2016; 329:12-29. [PMID: 27155147 DOI: 10.1016/j.neuroscience.2016.04.044] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 04/26/2016] [Accepted: 04/28/2016] [Indexed: 02/07/2023]
Abstract
Microglia are present throughout the central nervous system (CNS) and express receptors for every known neurotransmitter. During inflammation, microglia change into a state that either promotes removal of debris (M1), or into a state that promotes soothing (M2). Caudal- and rostral- ventrolateral medullary regions (CVLM and RVLM, respectively) of the brainstem are key nuclei involved in all aspects of the cardiovascular system. In this study, we investigate a novel role for microglia in cardiovascular control in the brainstem of adult male Sprague-Dawley (SD) rat. Here we show, that increases and decreases in blood pressure (BP) triggers alertness in the physiology of microglia in the brainstem region; inducing changes in microglial spatial distribution and the number of synapses in contact with microglial end processes. Following 6h of acute hypertension, the number of synapses in contact with microglia increased by ≈30% in both regions of the brainstem, CVLM and RVLM. Induction of acute hypotension for 6h causes microglia to reduce the number of synaptic contacts by >20% in both, CVLM and RVLM, nuclei of the brainstem. Our analysis of the morphological characteristics of microglia, and expression levels of M1 and M2, reveals that the changes induced in microglial behavior do not require any obvious dramatic changes in their morphology. Taken together, our findings suggest that microglia play a novel, unexpected, physiological role in the uninjured autonomic nuclei of CNS; we therefore speculate that microglia act cooperatively with brainstem cardiovascular neurons to maintain them in a physiologically receptive state.
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Affiliation(s)
- Komal Kapoor
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia; The Heart Research Institute, Sydney, New South Wales 2042, Australia
| | - Amol M Bhandare
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia; The Heart Research Institute, Sydney, New South Wales 2042, Australia
| | - Polina E Nedoboy
- The Heart Research Institute, Sydney, New South Wales 2042, Australia
| | - Suja Mohammed
- The Heart Research Institute, Sydney, New South Wales 2042, Australia; Department of Physiology, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Melissa M J Farnham
- The Heart Research Institute, Sydney, New South Wales 2042, Australia; Department of Physiology, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Paul M Pilowsky
- The Heart Research Institute, Sydney, New South Wales 2042, Australia; Department of Physiology, University of Sydney, Sydney, New South Wales 2006, Australia.
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Yu R, Zheng L, Cui Y, Zhang H, Ye H. Doxycycline exerted neuroprotective activity by enhancing the activation of neuropeptide GPCR PAC1. Neuropharmacology 2016; 103:1-15. [DOI: 10.1016/j.neuropharm.2015.11.032] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 11/14/2015] [Accepted: 11/30/2015] [Indexed: 02/06/2023]
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27
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Kim SJ, Kim YJ, Kakall Z, Farnham MMJ, Pilowsky PM. Intermittent hypoxia-induced cardiorespiratory long-term facilitation: A new role for microglia. Respir Physiol Neurobiol 2016; 226:30-8. [PMID: 27015670 DOI: 10.1016/j.resp.2016.03.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 03/18/2016] [Accepted: 03/18/2016] [Indexed: 02/07/2023]
Abstract
Intermittent hypoxia induces plasticity in neural networks controlling breathing and cardiovascular function. Studies demonstrate that mechanisms causing cardiorespiratory plasticity rely on intracellular signalling pathways that are activated by specific neurotransmitters. Peptides such as serotonin, PACAP and orexin are well-known for their physiological significance in regulating the cardiorespiratory system. Their receptor counterparts are present in cardiorespiratory centres of the brainstem medulla and spinal cord. Microglial cells are also important players in inducing plasticity. The phenotype and function of microglial cells can change based on the physiological state of the central nervous system. Here, we propose that in the autonomic nuclei of the ventral brainstem the relationship between neurotransmitters and neurokines, neurons and microglia determines the overall neural function of the central cardiorespiratory system.
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Affiliation(s)
- Seung Jae Kim
- Department of Physiology, Faculty of Medicine, The University of Sydney, Sydney, New South Wales 2006, Australia; The Heart Research Institute, 7 Eliza Street, Newtown, Sydney 2042, Australia
| | - Yeon Jae Kim
- Department of Physiology, Faculty of Medicine, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Zohra Kakall
- Department of Physiology, Faculty of Medicine, The University of Sydney, Sydney, New South Wales 2006, Australia; The Heart Research Institute, 7 Eliza Street, Newtown, Sydney 2042, Australia
| | - Melissa M J Farnham
- Department of Physiology, Faculty of Medicine, The University of Sydney, Sydney, New South Wales 2006, Australia; The Heart Research Institute, 7 Eliza Street, Newtown, Sydney 2042, Australia
| | - Paul M Pilowsky
- Department of Physiology, Faculty of Medicine, The University of Sydney, Sydney, New South Wales 2006, Australia; The Heart Research Institute, 7 Eliza Street, Newtown, Sydney 2042, Australia.
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