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Gano A, Wojcik H, Danseglio NC, Kelliher K, Varlinskaya EI, Deak T. Adolescent intermittent ethanol (AIE) sensitized fever in male Sprague Dawley rats exposed to poly I:C in adulthood. Brain Behav Immun 2024; 120:82-97. [PMID: 38777284 PMCID: PMC11269031 DOI: 10.1016/j.bbi.2024.05.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 05/13/2024] [Accepted: 05/19/2024] [Indexed: 05/25/2024] Open
Abstract
Fever plays an indispensable role in host defense processes and is used as a rapid index of infection severity. Unfortunately, there are also substantial individual differences in fever reactions with biological sex, immunological history, and other demographic variables contributing to adverse outcomes of infection. The present series of studies were designed to test the hypothesis that a history of adolescent alcohol misuse may be a latent experiential variable that determines fever severity using polyinosinic:polycytidylic acid (poly I:C), a synthetic form of double-stranded RNA that mimics a viral challenge. Adult male and female Sprague Dawley rats were injected with 0 (saline) or 4 mg/kg poly I:C to first establish sex differences in fever sensitivity in Experiment 1 using implanted radiotelemetry devices for remote tracking. In Experiments 2 and 3, adolescent males and females were exposed to either water or ethanol (0 or 4 g/kg intragastrically, 3 days on, 2 days off, ∼P30-P50, 4 cycles/12 exposures total). After a period of abstinence, adult rats (∼P80-96) were then challenged with saline or poly I:C, and fever induction and maintenance were examined across a prolonged time course of 8 h using implanted probes. In Experiments 4 and 5, adult male and female subjects with a prior history of adolescent water or adolescent intermittent ethanol (AIE) were given saline or poly I:C, with tissue collected for protein and gene expression analysis at 5 h post-injection. Initial sex differences in fever sensitivity were minimal in response to the 4 mg/kg dose of poly I:C in ethanol-naïve rats. AIE exposed males injected with poly I:C showed a sensitized fever response as well as enhanced TLR3, IκBα, and IL-1β expression in the nucleus of the solitary tract. Other brain regions related to thermoregulation and peripheral organs such as spleen, liver, and blood showed generalized immune responses to poly I:C, with no differences evident between AIE and water-exposed males. In contrast, AIE did not affect responsiveness to poly I:C in females. Thus, the present findings suggest that adolescent binge drinking may produce sex-specific and long-lasting effects on fever reactivity to viral infection, with preliminary evidence suggesting that these effects may be due to centrally-mediated changes in fever regulation rather than peripheral immunological mechanisms.
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Affiliation(s)
- Anny Gano
- Developmental Exposure Alcohol Research Center (DEARC), Behavioral Neuroscience Program, Department of Psychology, Binghamton University, Binghamton, NY, 13902-6000, USA
| | - Hannah Wojcik
- Developmental Exposure Alcohol Research Center (DEARC), Behavioral Neuroscience Program, Department of Psychology, Binghamton University, Binghamton, NY, 13902-6000, USA
| | - Nina C Danseglio
- Developmental Exposure Alcohol Research Center (DEARC), Behavioral Neuroscience Program, Department of Psychology, Binghamton University, Binghamton, NY, 13902-6000, USA
| | - Kaitlyn Kelliher
- Developmental Exposure Alcohol Research Center (DEARC), Behavioral Neuroscience Program, Department of Psychology, Binghamton University, Binghamton, NY, 13902-6000, USA
| | - Elena I Varlinskaya
- Developmental Exposure Alcohol Research Center (DEARC), Behavioral Neuroscience Program, Department of Psychology, Binghamton University, Binghamton, NY, 13902-6000, USA
| | - Terrence Deak
- Developmental Exposure Alcohol Research Center (DEARC), Behavioral Neuroscience Program, Department of Psychology, Binghamton University, Binghamton, NY, 13902-6000, USA.
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2
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Kobrzycka AT, Stankiewicz AM, Goscik J, Gora M, Burzynska B, Iwanicka-Nowicka R, Pierzchala-Koziec K, Wieczorek M. Hypothalamic Neurochemical Changes in Long-Term Recovered Bilateral Subdiaphragmatic Vagotomized Rats. Front Behav Neurosci 2022; 16:869526. [PMID: 35874650 PMCID: PMC9304976 DOI: 10.3389/fnbeh.2022.869526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 06/10/2022] [Indexed: 11/26/2022] Open
Abstract
Background Vagus nerve is one of the crucial routes in communication between the immune and central nervous systems. The impaired vagal nerve function may intensify peripheral inflammatory processes. This effect subsides along with prolonged recovery after permanent nerve injury. One of the results of such compensation is a normalized plasma concentration of stress hormone corticosterone – a marker of hypothalamic-pituitary-adrenal (HPA) axis activity. In this work, we strive to explain this corticosterone normalization by studying the mechanisms responsible for compensation-related neurochemical alterations in the hypothalamus. Materials and Methods Using microarrays and high performance liquid chromatography (HPLC), we measured genome-wide gene expression and major amino acid neurotransmitters content in the hypothalamus of bilaterally vagotomized rats, 1 month after surgery. Results Our results show that, in the long term, vagotomy affects hypothalamic amino acids concentration but not mRNA expression of tested genes. Discussion We propose an alternative pathway of immune to CNS communication after vagotomy, leading to activation of the HPA axis, by influencing central amino acids and subsequent monoaminergic neurotransmission.
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Affiliation(s)
- Anna Teresa Kobrzycka
- Department of Neurobiology, Faculty of Biology and Environmental Protection, University of Łodz, Łodz, Poland
- *Correspondence: Anna Teresa Kobrzycka,
| | - Adrian Mateusz Stankiewicz
- Department of Molecular Biology, Institute of Genetics and Animal Biotechnology, Polish Academy of Sciences, Jastrzebiec, Poland
| | - Joanna Goscik
- Software Department, Faculty of Computer Science, Bialystok University of Technology, Bialystok, Poland
| | - Monika Gora
- Department of Genetics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Beata Burzynska
- Department of Genetics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Roksana Iwanicka-Nowicka
- Department of Genetics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
- Faculty of Biology, University of Warsaw, Warsaw, Poland
| | | | - Marek Wieczorek
- Department of Neurobiology, Faculty of Biology and Environmental Protection, University of Łodz, Łodz, Poland
- Marek Wieczorek,
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3
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Tumanova TS, Kokurina TN, Rybakovа GI, Aleksandrov VG. Increased Systemic Level of Endotoxin Attenuates Baroreflex and Cardiovascular Effects of Infralimbic Cortex Electrostimulation in Anesthetized Rats. J EVOL BIOCHEM PHYS+ 2021. [DOI: 10.1134/s0022093021060235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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4
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Vitaliti G, Falsaperla R. Chorioamnionitis, Inflammation and Neonatal Apnea: Effects on Preterm Neonatal Brainstem and on Peripheral Airways: Chorioamnionitis and Neonatal Respiratory Functions. CHILDREN-BASEL 2021; 8:children8100917. [PMID: 34682182 PMCID: PMC8534519 DOI: 10.3390/children8100917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/01/2021] [Accepted: 10/13/2021] [Indexed: 11/16/2022]
Abstract
Background: The present manuscript aims to be a narrative review evaluating the association between inflammation in chorioamnionitis and damage on respiratory centers, peripheral airways, and lungs, explaining the pathways responsible for apnea in preterm babies born by delivery after chorioamnionitis. Methods: A combination of keywords and MESH words was used, including: "inflammation", "chorioamnionitis", "brainstem", "cytokines storm", "preterm birth", "neonatal apnea", and "apnea physiopathology". All identified papers were screened for title and abstracts by the two authors to verify whether they met the proper criteria to write the topic. Results: Chorioamnionitis is usually associated with Fetal Inflammatory Response Syndrome (FIRS), resulting in injury of brain and lungs. Literature data have shown that infections causing chorioamnionitis are mostly associated with inflammation and consequent hypoxia-mediated brain injury. Moreover, inflammation and infection induce apneic episodes in neonates, as well as in animal samples. Chorioamnionitis-induced inflammation favors the systemic secretion of pro-inflammatory cytokines that are involved in abnormal development of the respiratory centers in the brainstem and in alterations of peripheral airways and lungs. Conclusions: Preterm birth shows a suboptimal development of the brainstem and abnormalities and altered development of peripheral airways and lungs. These alterations are responsible for reduced respiratory control and apnea. To date, mostly animal studies have been published. Therefore, more clinical studies on the role of chorioamninitis-induced inflammation on prematurity and neonatal apnea are necessary.
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Affiliation(s)
- Giovanna Vitaliti
- Unit of Pediatrics, Department of Medical Sciences, Section of Pediatrics, University of Ferrara, 44121 Ferrara, Italy
- Correspondence: ; Tel.: +39-34-0471-0614
| | - Raffaele Falsaperla
- Pediatrics and Pediatric Emergency Operative Unit, Azienda Ospedaliero Universitaria Policlinico G.Rodolico-San Marco, San Marco Hospital, University of Catania, 95124 Catania, Italy;
- Neonatal Intensive Care Unit, Azienda Ospedaliero Universitaria Policlinico G.Rodolico-San Marco, San Marco Hospital, San Marco Hospital, University of Catania, 95124 Catania, Italy
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5
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Marty VN, Farokhnia M, Munier JJ, Mulpuri Y, Leggio L, Spigelman I. Long-Acting Glucagon-Like Peptide-1 Receptor Agonists Suppress Voluntary Alcohol Intake in Male Wistar Rats. Front Neurosci 2020; 14:599646. [PMID: 33424537 PMCID: PMC7785877 DOI: 10.3389/fnins.2020.599646] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 12/03/2020] [Indexed: 12/21/2022] Open
Abstract
Alcohol use disorder (AUD) is a chronic relapsing condition characterized by compulsive alcohol-seeking behaviors, with serious detrimental health consequences. Despite high prevalence and societal burden, available approved medications to treat AUD are limited in number and efficacy, highlighting a critical need for more and novel pharmacotherapies. Glucagon-like peptide-1 (GLP-1) is a gut hormone and neuropeptide involved in the regulation of food intake and glucose metabolism via GLP-1 receptors (GLP-1Rs). GLP-1 analogs are approved for clinical use for diabetes and obesity. Recently, the GLP-1 system has been shown to play a role in the neurobiology of addictive behaviors, including alcohol seeking and consumption. Here we investigated the effects of different pharmacological manipulations of the GLP-1 system on escalated alcohol intake and preference in male Wistar rats exposed to intermittent access 2-bottle choice of 10% ethanol or water. Administration of AR231453 and APD668, two different agonists of G-protein receptor 119, whose activation increases GLP-1 release from intestinal L-cells, did not affect voluntary ethanol intake. By contrast, injections of either liraglutide or semaglutide, two long-acting GLP-1 analogs, potently decreased ethanol intake. These effects, however, were transient, lasting no longer than 48 h. Semaglutide, but not liraglutide, also reduced ethanol preference on the day of injection. As expected, both analogs induced a reduction in body weight. Co-administration of exendin 9-39, a GLP-1R antagonist, did not prevent liraglutide- or semaglutide-induced effects in this study. Injection of exendin 9-39 alone, or blockade of dipeptidyl peptidase-4, an enzyme responsible for GLP-1 degradation, via injection of sitagliptin, did not affect ethanol intake or preference. Our findings suggest that among medications targeting the GLP-1 system, GLP-1 analogs may represent novel and promising pharmacological tools for AUD treatment.
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Affiliation(s)
- Vincent N Marty
- Laboratory of Neuropharmacology, Section of Oral Biology, School of Dentistry, University of California, Los Angeles, Los Angeles, CA, United States
| | - Mehdi Farokhnia
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Bethesda, MD, United States.,Center on Compulsive Behaviors, National Institutes of Health, Bethesda, MD, United States.,Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Joseph J Munier
- Laboratory of Neuropharmacology, Section of Oral Biology, School of Dentistry, University of California, Los Angeles, Los Angeles, CA, United States
| | - Yatendra Mulpuri
- Laboratory of Neuropharmacology, Section of Oral Biology, School of Dentistry, University of California, Los Angeles, Los Angeles, CA, United States
| | - Lorenzo Leggio
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Bethesda, MD, United States.,Center on Compulsive Behaviors, National Institutes of Health, Bethesda, MD, United States.,Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, Brown University, Providence, RI, United States.,Medication Development Program, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, United States.,Division of Addiction Medicine, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, United States.,Department of Neuroscience, Georgetown University Medical Center, Washington, DC, United States
| | - Igor Spigelman
- Laboratory of Neuropharmacology, Section of Oral Biology, School of Dentistry, University of California, Los Angeles, Los Angeles, CA, United States
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Cao Y, Liu T, Li Z, Yang J, Ma L, Mi X, Yang N, Qi A, Guo X, Wang A. Neurofilament degradation is involved in laparotomy-induced cognitive dysfunction in aged rats. Aging (Albany NY) 2020; 12:25643-25657. [PMID: 33232265 PMCID: PMC7803518 DOI: 10.18632/aging.104172] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 09/19/2020] [Indexed: 12/04/2022]
Abstract
Excessive neuroinflammatory responses play important roles in the development of postoperative cognitive dysfunction (POCD). Neurofilaments (NFs) were essential to the structure of axon and nerve conduction; and the abnormal degradation of NFs were always accompanied with degenerative diseases, which were also characterized by excessive neuroinflammatory responses in brain. However, it is still unclear whether the NFs were involved in the POCD. In this study, the LC-MS/MS method was used to explore the neuroinflammatory response and NFs of POCD in aged rats. Moreover, trichostatin A (TSA), an inflammation-related drug, was selected to test whether it could improve the surgery-induced cognitive dysfunction, inflammatory responses and NFs. Evident cognitive dysfunction, excessive microglia activation, neuroinflammatory responses and upregulated NFs in hippocampus were observed in the POCD group. TSA pretreatment could significantly mitigate these changes. The KEGG analysis revealed that nine pathways were enriched in the TSA + surgery group (versus the surgery group). Among them, two signaling pathways were closely related with the changes of NFs proteins. In conclusion, surgery could impair the cognitive function and aggravate neuroinflammation and NFs. The TSA could significantly improve these changes which might be related to the activation of the “focal adhesion” and “ECM-receptor interaction” pathways.
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Affiliation(s)
- Yiyun Cao
- Department of Anesthesiology, Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University, Shanghai 200233, China
| | - Taotao Liu
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Zhengqian Li
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Jiao Yang
- Department of Pharmacy, Sixth People’s Hospital East Campus Affiliated to Shanghai Jiao Tong University, Shanghai 200233, China
| | - Lijun Ma
- Department of Medical Imaging, North Minzu University, Yinchuan, Ningxia 750021, China
| | - Xinning Mi
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Ning Yang
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Aihua Qi
- Department of Anesthesiology, Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University, Shanghai 200233, China
| | - Xiangyang Guo
- Department of Anesthesiology, Peking University Third Hospital, Beijing 100191, China
| | - Aizhong Wang
- Department of Anesthesiology, Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University, Shanghai 200233, China
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7
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Litvin DG, Denstaedt SJ, Borkowski LF, Nichols NL, Dick TE, Smith CB, Jacono FJ. Peripheral-to-central immune communication at the area postrema glial-barrier following bleomycin-induced sterile lung injury in adult rats. Brain Behav Immun 2020; 87:610-633. [PMID: 32097765 PMCID: PMC8895345 DOI: 10.1016/j.bbi.2020.02.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 02/02/2020] [Accepted: 02/13/2020] [Indexed: 02/07/2023] Open
Abstract
The pathways for peripheral-to-central immune communication (P → C I-comm) following sterile lung injury (SLI) are unknown. SLI evokes systemic and central inflammation, which alters central respiratory control and viscerosensory transmission in the nucleus tractus solitarii (nTS). These functional changes coincide with increased interleukin-1 beta (IL-1β) in the area postrema, a sensory circumventricular organ that connects P → C I-comm to brainstem circuits that control homeostasis. We hypothesize that IL-1β and its downstream transcriptional target, cyclooxygenase-2 (COX-2), mediate P → C I-comm in the nTS. In a rodent model of SLI induced by intratracheal bleomycin (Bleo), the sigh frequency and duration of post-sigh apnea increased in Bleo- compared to saline- treated rats one week after injury. This SLI-dependent change in respiratory control occurred concurrently with augmented IL-1β and COX-2 immunoreactivity (IR) in the funiculus separans (FS), a barrier between the AP and the brainstem. At this barrier, increases in IL-1β and COX-2 IR were confined to processes that stained for glial fibrillary acidic protein (GFAP) and that projected basolaterally to the nTS. Further, FS radial-glia did not express TNF-α or IL-6 following SLI. To test our hypothesis, we blocked central COX-1/2 activity by intracerebroventricular (ICV) infusion of Indomethacin (Ind). Continuous ICV Ind treatment prevented Bleo-dependent increases in GFAP + and IL-1β + IR, and restored characteristics of sighs that reset the rhythm. These data indicate that changes in sighs following SLI depend partially on activation of a central COX-dependent P → C I-comm via radial-glia of the FS.
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Affiliation(s)
- David G Litvin
- Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Department of Fundamental Neuroscience, University of Lausanne, 1005 Lausanne, Switzerland
| | - Scott J Denstaedt
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109, United States
| | - Lauren F Borkowski
- Department of Biomedical Sciences, University of Missouri College of Veterinary Medicine, Columbia, MO 65212, United States
| | - Nicole L Nichols
- Department of Biomedical Sciences, University of Missouri College of Veterinary Medicine, Columbia, MO 65212, United States
| | - Thomas E Dick
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States
| | - Corey B Smith
- Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States
| | - Frank J Jacono
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Division of Pulmonary, Critical Care and Sleep Medicine, Louis Stokes VA Medical Center, Cleveland, OH 44106, United States.
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8
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Hsieh YH, Litvin DG, Zaylor AR, Nethery DE, Dick TE, Jacono FJ. Brainstem inflammation modulates the ventilatory pattern and its variability after acute lung injury in rodents. J Physiol 2020; 598:2791-2811. [PMID: 32378188 DOI: 10.1113/jp279177] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 04/21/2020] [Indexed: 01/20/2023] Open
Abstract
KEY POINTS Compared with sham rats, rats a week after acute lung injury (ALI) express more pro-inflammatory cytokines in their brainstem respiratory control nuclei, exhibit a higher respiratory frequency (fR) and breathe with a more predictable pattern. These characteristics of the respiratory pattern persist in in situ preparations even after minimizing pulmonary and chemo-afferent inputs. Interleukin (IL)-1β microinjected in the nucleus tractus solitarii increases fR and the predictability of the ventilatory pattern similar to rats with ALI. Intracerebroventricular infusion of indomethacin, an anti-inflammatory drug, mitigates the effect of ALI on fR and ventilatory pattern variability. We conclude that changes in the ventilatory pattern after ALI result not only from sensory input due to pulmonary damage and dysfunction but also from neuro-inflammation. ABSTRACT Acute lung injury (ALI) increases respiratory rate (fR) and ventilatory pattern variability (VPV), but also evokes peripheral and central inflammation. We hypothesized that central inflammation has a role in determining the ventilatory pattern after ALI. In rat pups, we intratracheally injected either bleomycin to induce ALI or saline as a sham control. One week later, we recorded the ventilatory pattern of the rat pups using flow-through plethysmography, then formed in situ preparations from these pups and recorded their 'fictive' patterns from respiratory motor nerves. Compared with the ventilatory pattern of the sham rat pups, injured rat pups had increased fR and predictability. Surprisingly, the fictive patterns of the in situ preparations from ALI pups retained these characteristics despite removing their lungs to eliminate pulmonary sensory inputs and perfusing them with hyperoxic artificial cerebral spinal fluid to minimize peripheral chemoreceptor input. Histological processing revealed increased immunoreactivity of the pro-inflammatory cytokine Interleukin-1β (IL-1β) in the nucleus tractus solitarii (nTS) from ALI but not sham rats. In subsequent experiments, we microinjected IL-1β in the nTS bilaterally in anaesthetized naïve adult rats, which increased fR and predictability of ventilatory pattern variability (VPV) after 2 h. Finally, we infused indomethacin intracerebroventricularly during the week of survival after ALI. This did not affect sham rats, but mitigated changes in fR and VPV in ALI rats. We conclude that neuro-inflammation has an essential role in determining the ventilatory pattern of ALI rats.
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Affiliation(s)
- Yee-Hsee Hsieh
- Division of Pulmonary, Critical Care and Sleep Medicine, Case Western Reserve University, Cleveland, Ohio, United States
| | - David G Litvin
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States.,Department of Fundamental Neuroscience, University of Lausanne, Lausanne, 1005, Switzerland
| | - Abigail R Zaylor
- Division of Pulmonary, Critical Care and Sleep Medicine, Case Western Reserve University, Cleveland, Ohio, United States.,Division of Pulmonary, Critical Care and Sleep Medicine, Louis Stokes VA Medical Center, Cleveland, Ohio, United States
| | - David E Nethery
- Division of Pulmonary, Critical Care and Sleep Medicine, Case Western Reserve University, Cleveland, Ohio, United States
| | - Thomas E Dick
- Division of Pulmonary, Critical Care and Sleep Medicine, Case Western Reserve University, Cleveland, Ohio, United States.,Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio, United States
| | - Frank J Jacono
- Division of Pulmonary, Critical Care and Sleep Medicine, Case Western Reserve University, Cleveland, Ohio, United States.,Division of Pulmonary, Critical Care and Sleep Medicine, Louis Stokes VA Medical Center, Cleveland, Ohio, United States
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Donnelly WT, Haynes RL, Commons KG, Erickson DJ, Panzini CM, Xia L, Han QJ, Leiter JC. Prenatal intermittent hypoxia sensitizes the laryngeal chemoreflex, blocks serotoninergic shortening of the reflex, and reduces 5-HT 3 receptor binding in the NTS in anesthetized rat pups. Exp Neurol 2020; 326:113166. [PMID: 31887303 PMCID: PMC7028519 DOI: 10.1016/j.expneurol.2019.113166] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 12/14/2019] [Accepted: 12/26/2019] [Indexed: 10/25/2022]
Abstract
We tested the hypothesis that exposure to intermittent hypoxia (IH) during pregnancy would prolong the laryngeal chemoreflex (LCR) and diminish the capacity of serotonin (5-hydroxytryptamine; 5-HT) to terminate the LCR. Prenatal exposure to IH was associated with significant prolongation of the LCR in younger, anesthetized, postnatal day (P) rat pups age P8 to P16 compared to control, room air (RA)-exposed rat pups of the same age. Serotonin microinjected into the NTS shortened the LCR in rat pups exposed to RA during gestation, but 5-HT failed to shorten the LCR in rat pups exposed to prenatal IH. Given these observations, we tested the hypothesis that prenatal hypoxia would decrease binding to 5-HT3 receptors in the nucleus of the solitary tract (NTS) where 5-HT acts to shorten the LCR. Serotonin 3 receptor binding was reduced in younger rat pups exposed to IH compared to control, RA-exposed rat pups in the age range P8 to P12. Serotonin 3 receptor binding was similar in older animals (P18-P24) regardless of gas exposure during gestation. The failure of the 5-HT injected into the NTS to shorten the LCR was correlated with a developmental decrease in 5-HT3 receptor binding in the NTS associated with exposure to prenatal IH. In summary, prenatal IH sensitized reflex apnea and blunted processes that terminate reflex apneas in neonatal rat pups, processes that are essential to prevent death following apneas such as those seen in babies who died of SIDS.
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Affiliation(s)
- William T Donnelly
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, One Rope Ferry Road, Hanover, NH 03755, United States of America
| | - Robin L Haynes
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, United States of America
| | - Kathryn G Commons
- Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital and Harvard Medical School, United States of America
| | - Drexel J Erickson
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, United States of America
| | - Chris M Panzini
- Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital and Harvard Medical School, United States of America
| | - Luxi Xia
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, One Rope Ferry Road, Hanover, NH 03755, United States of America
| | - Q Joyce Han
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, One Rope Ferry Road, Hanover, NH 03755, United States of America
| | - J C Leiter
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, One Rope Ferry Road, Hanover, NH 03755, United States of America.
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10
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Effects of inflammation on the developing respiratory system: Focus on hypoglossal (XII) neuron morphology, brainstem neurochemistry, and control of breathing. Respir Physiol Neurobiol 2020; 275:103389. [PMID: 31958568 DOI: 10.1016/j.resp.2020.103389] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 01/03/2020] [Accepted: 01/16/2020] [Indexed: 12/20/2022]
Abstract
Breathing is fundamental to life and any adverse change in respiratory function can endanger the health of an organism or even be fatal. Perinatal inflammation is known to adversely affect breathing in preterm babies, but lung infection/inflammation impacts all stages of life from birth to death. Little is known about the role of inflammation in respiratory control, neuronal morphology, or neural function during development. Animal models of inflammation can provide understanding and insight into respiratory development and how inflammatory processes alter developmental phenotype in addition to providing insight into new treatment modalities. In this review, we focus on recent work concerning the development of neurons, models of perinatal inflammation with an emphasis on two common LPS-based models, inflammation and its impact on development, and current and potential treatments for inflammation within the respiratory control circuitry of the mammalian brainstem. We have also discussed models of inflammation in adults and have specifically focused on hypoglossal motoneurons (XII) and neurons of the nucleus tractus solitarii (nTS) as these nuclei have been studied more extensively than other brainstem nuclei participating in breathing and airway control. Understanding the impact of inflammation on the developmental aspects of respiratory control and breathing pattern is critical to addressing problems of cardiorespiratory dysregulation in disease and this overview points out many gaps in our current knowledge.
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Getsy PM, Mayer CA, MacFarlane PM, Jacono FJ, Wilson CG. Acute lung injury in neonatal rats causes postsynaptic depression in nucleus tractus solitarii second-order neurons. Respir Physiol Neurobiol 2019; 269:103250. [PMID: 31352011 DOI: 10.1016/j.resp.2019.103250] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 06/14/2019] [Accepted: 07/02/2019] [Indexed: 12/28/2022]
Abstract
Acute Lung Injury (ALI) alters pulmonary reflex responses, in part due to changes in modulation within the lung and airway neuronal control networks. We hypothesized that synaptic efficacy of nucleus tractus solitarii (nTS) neurons, receiving input from lung, airway, and other viscerosensory afferent fibers, would decrease following ALI. Sprague Dawley neonatal rats (postnatal days 9-11) were given intratracheal installations of saline or bleomycin (a well-characterized model that reproduces the pattern of ALI) and then, one week later, in vitro slices were prepared for whole-cell and perforated whole-cell patch-clamp experiments (postnatal days 16-21). In preparations from ALI rats, 2nd-order nTS neurons had significantly decreased amplitudes of both spontaneous and miniature excitatory postsynaptic currents (sEPSCs and mEPSCs), compared to saline controls. Rise and decay times of sEPSCs were slower in whole-cell recordings from ALI animals. Similarly, the amplitude of tractus solitarii evoked EPSCs (TS-eEPSCs) were significantly lower in 2nd-order nTS neurons from ALI rats. Overall these results suggest the presence of postsynaptic depression at TS-nTS synapses receiving lung, airway, and other viscerosensory afferent tractus solitarii input after bleomycin-induced ALI.
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Affiliation(s)
- Paulina M Getsy
- Department of Physiology and Biophysics, CWRU School of Medicine, Cleveland, OH, 44106, United States; Department of Pediatrics, Rainbow Babies & Children's Hospital, CWRU School of Medicine, Cleveland, OH, 44106, United States
| | - Catherine A Mayer
- Department of Pediatrics, Rainbow Babies & Children's Hospital, CWRU School of Medicine, Cleveland, OH, 44106, United States
| | - Peter M MacFarlane
- Department of Pediatrics, Rainbow Babies & Children's Hospital, CWRU School of Medicine, Cleveland, OH, 44106, United States
| | - Frank J Jacono
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, CWRU School of Medicine, Cleveland, OH, 44106, United States; Division of Pulmonary, Critical Care and Sleep Medicine, Louis Stokes VA Medical Center, Cleveland, OH, 44106, United States
| | - Christopher G Wilson
- Department of Pediatrics and Lawrence D. Long, MD Center for Perinatal Biology Loma Linda University Loma Linda, CA, United States.
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12
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Kobrzycka A, Napora P, Pearson BL, Pierzchała-Koziec K, Szewczyk R, Wieczorek M. Peripheral and central compensatory mechanisms for impaired vagus nerve function during peripheral immune activation. J Neuroinflammation 2019; 16:150. [PMID: 31324250 PMCID: PMC6642550 DOI: 10.1186/s12974-019-1544-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 07/10/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Determining the etiology and possible treatment strategies for numerous diseases requires a comprehensive understanding of compensatory mechanisms in physiological systems. The vagus nerve acts as a key interface between the brain and the peripheral internal organs. We set out to identify mechanisms compensating for a lack of neuronal communication between the immune and the central nervous system (CNS) during infection. METHODS We assessed biochemical and central neurotransmitter changes resulting from subdiaphragmatic vagotomy and whether they are modulated by intraperitoneal infection. We performed a series of subdiaphragmatic vagotomy or sham operations on male Wistar rats. Next, after full, 30-day recovery period, they were randomly assigned to receive an injection of Escherichia coli lipopolysaccharide or saline. Two hours later, animal were euthanized and we measured the plasma concentration of prostaglandin E2 (with HPLC-MS), interleukin-6 (ELISA), and corticosterone (RIA). We also had measured the concentration of monoaminergic neurotransmitters and their metabolites in the amygdala, brainstem, hippocampus, hypothalamus, motor cortex, periaqueductal gray, and prefrontal medial cortex using RP-HPLC-ED. A subset of the animals was evaluated in the elevated plus maze test immediately before euthanization. RESULTS The lack of immunosensory signaling of the vagus nerve stimulated increased activity of discrete inflammatory marker signals, which we confirmed by quantifying biochemical changes in blood plasma. Behavioral results, although preliminary, support the observed biochemical alterations. Many of the neurotransmitter changes observed after vagotomy indicated that the vagus nerve influences the activity of many brain areas involved in control of immune response and sickness behavior. Our studies show that these changes are largely eliminated during experimental infection. CONCLUSIONS Our results suggest that in vagotomized animals with blocked CNS, communication may transmit via a pathway independent of the vagus nerve to permit restoration of CNS activity for peripheral inflammation control.
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Affiliation(s)
- Anna Kobrzycka
- Department of Neurobiology, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland
| | - Paweł Napora
- Department of Neurobiology, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland
| | - Brandon L. Pearson
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, USA
| | | | - Rafał Szewczyk
- Department of Industrial Microbiology and Biotechnology, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland
| | - Marek Wieczorek
- Department of Neurobiology, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland
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13
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Chang RB. Body thermal responses and the vagus nerve. Neurosci Lett 2019; 698:209-216. [PMID: 30634012 PMCID: PMC7061531 DOI: 10.1016/j.neulet.2019.01.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 01/04/2019] [Accepted: 01/07/2019] [Indexed: 12/17/2022]
Abstract
While thermosensation from external environment has been extensively studied, physiological responses to temperature changes inside the body and the underlying regulatory mechanisms are less understood. As a critical link between body and brain that relays visceral organ information and regulates numerous physiological functions, the vagus nerve has been proposed to mediate diverse visceral thermal reflexes and indirectly regulate body temperature. However, the precise role of the vagus nerve in body thermal responses or visceral organ-related thermoregulation is still under debate due to extensive contradictory results. This data discrepancy is likely due to the high cell heterogeneity in the vagus nerve, as diverse vagal neuron types mediate numerous and sometimes opposite physiological functions. Here, we will review evidences that support and against the role of the vagus nerve in body thermosensation and thermoregulation and discuss potential future approaches for better understanding of this critical issue.
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Affiliation(s)
- Rui B Chang
- Department of Neuroscience, Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, 06520, United States.
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14
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Khazaeipool Z, Wiederman M, Inoue W. Prostaglandin E 2 depresses GABA release onto parvocellular neuroendocrine neurones in the paraventricular nucleus of the hypothalamus via presynaptic receptors. J Neuroendocrinol 2018; 30:e12638. [PMID: 30084511 DOI: 10.1111/jne.12638] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 08/02/2018] [Accepted: 08/04/2018] [Indexed: 12/12/2022]
Abstract
Inflammation-induced activation of the hypothalamic-pituitary-adrenal (HPA) axis and the ensuing release of anti-inflammatory glucocorticoids are critical for the fine-tuning of the inflammatory response. This immune-induced neuroendocrine response is in large part mediated by prostaglandin E2 (PGE2 ), the central actions of which ultimately translate into the excitation of parvocellular neuroendocrine cells (PNCs) in the hypothalamic paraventricular nucleus. However, the neuronal mechanisms by which PGE2 excites PNCs remain incompletely understood. In the present study, we report that PGE2 potently depresses GABAergic inhibitory synaptic transmission onto PNCs. Using whole-cell patch clamp recordings obtained from PNCs in ex vivo hypothalamic slices from rats, we found that bath application of PGE2 (0.01-100 μmol L-1 ) concentration-dependently decreased the amplitude of evoked inhibitory postsynaptic currents (eIPSCs) with maximum effects at 10 μmol L-1 . The PGE2 -mediated depression of eIPSCs had a rapid onset and was long-lasting, and also was accompanied by an increase in paired pulse ratio. In addition, PGE2 decreased the frequency but not the amplitude of both spontaneous IPSCs and miniature IPSCs. These results collectively indicate that PGE2 acts at a presynaptic locus to decrease the probability of GABA release. Using pharmacological approaches, we also demonstrated that the EP3 subtype of the PGE2 receptor mediated the actions of PGE2 on GABA synapses. Taken together, our results show that PGE2 , via actions of presynaptic EP3 receptors, potently depresses GABA release onto PNCs, providing a plausible mechanism for the disinhibition of HPA axis output during inflammation.
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Affiliation(s)
- Zahra Khazaeipool
- Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Meagan Wiederman
- Neuroscience Program, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Wataru Inoue
- Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
- Neuroscience Program, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
- Robarts Research Institute, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
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15
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Brown AG, Thapa M, Hooker JW, Ostrowski TD. Impaired chemoreflex correlates with decreased c-Fos in respiratory brainstem centers of the streptozotocin-induced Alzheimer's disease rat model. Exp Neurol 2018; 311:285-292. [PMID: 30359566 DOI: 10.1016/j.expneurol.2018.10.012] [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: 07/30/2018] [Revised: 09/17/2018] [Accepted: 10/20/2018] [Indexed: 12/29/2022]
Abstract
Besides impairment in cognition and memory, patients with Alzheimer's disease (AD) often exhibit marked dysfunction in respiratory control. Sleep-disordered breathing (SDB) is commonly found in cases of AD, resulting in periods of hypoxia during sleep. Early structural changes in brainstem areas controlling respiratory function may account for SDB in the course of AD. However, to date the underlying mechanisms for these complications are not known. The streptozotocin (STZ)-induced rat model of AD exhibits abnormal responses to hypoxia and increased astrogliosis in a key region for respiratory control. In this study we further defined the pathophysiological respiratory response of STZ-AD rats to 10% O2. In addition, we analyzed hypoxia-induced neuronal activation in respiratory and cardiovascular nuclei of the dorsal and ventral brainstem. Two hours of hypoxia induced a transient increase in tidal volume that was followed by a prolonged increase in respiratory rate. Only respiratory rate was significantly blunted in the STZ-AD model, which continued over the entire duration of the hypoxic episode. Analysis of c-Fos expression as a marker for neuronal activation showed abundant labeling throughout the nTS, nuclei of the ventral respiratory column, and A1/C1 cells of cardiovascular centers in the ventral brainstem. STZ-AD rats showed a significant decrease of c-Fos labeling in the caudal/medial nTS, rostral ventral respiratory group, and Bötzinger complex. c-Fos in other respiratory centers and A1/C1 cells was unaltered when compared to control. The results of this study document a region-specific impact of STZ-induced AD in respiratory brainstem nuclei. This decrease in c-Fos expression correlates with the observed blunting of respiration to hypoxia in the STZ-AD rat model.
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Affiliation(s)
- Andrea G Brown
- Department of Physiology, Kirksville College of Osteopathic Medicine, A.T. Still University of Health Sciences, Kirksville, MO, USA
| | - Mahima Thapa
- Department of Biology, Truman State University, Kirksville, MO, USA
| | - John W Hooker
- Department of Biology, Truman State University, Kirksville, MO, USA
| | - Tim D Ostrowski
- Department of Physiology, Kirksville College of Osteopathic Medicine, A.T. Still University of Health Sciences, Kirksville, MO, USA.
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16
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Reardon C, Murray K, Lomax AE. Neuroimmune Communication in Health and Disease. Physiol Rev 2018; 98:2287-2316. [PMID: 30109819 PMCID: PMC6170975 DOI: 10.1152/physrev.00035.2017] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 04/09/2018] [Accepted: 04/09/2018] [Indexed: 12/14/2022] Open
Abstract
The immune and nervous systems are tightly integrated, with each system capable of influencing the other to respond to infectious or inflammatory perturbations of homeostasis. Recent studies demonstrating the ability of neural stimulation to significantly reduce the severity of immunopathology and consequently reduce mortality have led to a resurgence in the field of neuroimmunology. Highlighting the tight integration of the nervous and immune systems, afferent neurons can be activated by a diverse range of substances from bacterial-derived products to cytokines released by host cells. While activation of vagal afferents by these substances dominates the literature, additional sensory neurons are responsive as well. It is becoming increasingly clear that although the cholinergic anti-inflammatory pathway has become the predominant model, a multitude of functional circuits exist through which neuronal messengers can influence immunological outcomes. These include pathways whereby efferent signaling occurs independent of the vagus nerve through sympathetic neurons. To receive input from the nervous system, immune cells including B and T cells, macrophages, and professional antigen presenting cells express specific neurotransmitter receptors that affect immune cell function. Specialized immune cell populations not only express neurotransmitter receptors, but express the enzymatic machinery required to produce neurotransmitters, such as acetylcholine, allowing them to act as signaling intermediaries. Although elegant experiments have begun to decipher some of these interactions, integration of these molecules, cells, and anatomy into defined neuroimmune circuits in health and disease is in its infancy. This review describes these circuits and highlights continued challenges and opportunities for the field.
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Affiliation(s)
- Colin Reardon
- Department of Anatomy, Physiology, and Cell Biology, UC Davis School of Veterinary Medicine, UC Davis, Davis, California ; and Department of Biomedical and Molecular Sciences and Department of Medicine, Queen's University , Kingston, Ontario , Canada
| | - Kaitlin Murray
- Department of Anatomy, Physiology, and Cell Biology, UC Davis School of Veterinary Medicine, UC Davis, Davis, California ; and Department of Biomedical and Molecular Sciences and Department of Medicine, Queen's University , Kingston, Ontario , Canada
| | - Alan E Lomax
- Department of Anatomy, Physiology, and Cell Biology, UC Davis School of Veterinary Medicine, UC Davis, Davis, California ; and Department of Biomedical and Molecular Sciences and Department of Medicine, Queen's University , Kingston, Ontario , Canada
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17
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Abstract
Fever is a common symptom of infectious and inflammatory disease. It is well-established that prostaglandin E2 is the final mediator of fever, which by binding to its EP3 receptor subtype in the preoptic hypothalamus initiates thermogenesis. Here, we review the different hypotheses on how the presence of peripherally released pyrogenic substances can be signaled to the brain to elicit fever. We conclude that there is unequivocal evidence for a humoral signaling pathway by which proinflammatory cytokines, through their binding to receptors on brain endothelial cells, evoke fever by eliciting prostaglandin E2 synthesis in these cells. The evidence for a role for other signaling routes for fever, such as signaling via circumventricular organs and peripheral nerves, as well as transfer into the brain of peripherally synthesized prostaglandin E2 are yet far from conclusive. We also review the efferent limb of the pyrogenic pathways. We conclude that it is well established that prostaglandin E2 binding in the preoptic hypothalamus produces fever by disinhibition of presympathetic neurons in the brain stem, but there is yet little understanding of the mechanisms by which factors such as nutritional status and ambient temperature shape the response to the peripheral immune challenge.
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Affiliation(s)
- Anders Blomqvist
- Department of Clinical and Experimental Medicine, Faculty of Medicine and Health, Linköping University, Linköping, Sweden
| | - David Engblom
- Department of Clinical and Experimental Medicine, Faculty of Medicine and Health, Linköping University, Linköping, Sweden
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18
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Litvin DG, Dick TE, Smith CB, Jacono FJ. Lung-injury depresses glutamatergic synaptic transmission in the nucleus tractus solitarii via discrete age-dependent mechanisms in neonatal rats. Brain Behav Immun 2018; 70:398-422. [PMID: 29601943 PMCID: PMC6075724 DOI: 10.1016/j.bbi.2018.03.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 03/20/2018] [Accepted: 03/26/2018] [Indexed: 12/26/2022] Open
Abstract
Transition periods (TPs) are brief stages in CNS development where neural circuits can exhibit heightened vulnerability to pathologic conditions such as injury or infection. This susceptibility is due in part to specialized mechanisms of synaptic plasticity, which may become activated by inflammatory mediators released under pathologic conditions. Thus, we hypothesized that the immune response to lung injury (LI) mediated synaptic changes through plasticity-like mechanisms that depended on whether LI occurred just before or after a TP. We studied the impact of LI on brainstem 2nd-order viscerosensory neurons located in the nucleus tractus solitarii (nTS) during a TP for respiratory control spanning (postnatal day (P) 11-15). We injured the lungs of Sprague-Dawley rats by intratracheal instillation of Bleomycin (or saline) just before (P9-11) or after (P17-19) the TP. A week later, we prepared horizontal slices of the medulla and recorded spontaneous and evoked excitatory postsynaptic currents (sEPSCs/eEPSCs) in vitro from neurons in the nTS that received monosynaptic glutamatergic input from the tractus solitarii (TS). In rats injured before the TP (pre-TP), neurons exhibited blunted sEPSCs and TS-eEPSCs compared to controls. The decreased TS-eEPSCs were mediated by differences in postsynaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic-acid receptors (AMPAR). Specifically, compared to controls, LI rats had more Ca2+-impermeable AMPARs (CI-AMPARs) as indicated by: 1) the absence of current-rectification, 2) decreased sensitivity to polyamine, 1-Naphthyl-acetyl-spermine-trihydrochloride (NASPM) and 3) augmented immunoreactive staining for the CI-AMPAR GluA2. Thus, pre-TP-LI acts postsynaptically to blunt glutamatergic transmission. The neuroimmune response to pre-TP-LI included microglia hyper-ramification throughout the nTS. Daily intraperitoneal administration of minocycline, an inhibitor of microglial/macrophage function prevented hyper-ramification and abolished the pre-TP-LI evoked synaptic changes. In contrast, rat-pups injured after the TP (post-TP) exhibited microglia hypo-ramification in the nTS and had increased sEPSC amplitudes/frequencies, and decreased TS-eEPSC amplitudes compared to controls. These synaptic changes were not associated with changes in CI-AMPARs, and instead involved greater TS-evoked use-dependent depression (reduced paired pulse ratio), which is a hallmark of presynaptic plasticity. Thus we conclude that LI regulates the efficacy of TS → nTS synapses through discrete plasticity-like mechanisms that are immune-mediated and depend on whether the injury occurs before or after the TP for respiratory control.
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Affiliation(s)
- David G Litvin
- Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Division of Pulmonary, Critical Care and Sleep Medicine, Louis Stokes VA Medical Center, Cleveland, OH 44106, United States
| | - Thomas E Dick
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States
| | - Corey B Smith
- Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States
| | - Frank J Jacono
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States; Division of Pulmonary, Critical Care and Sleep Medicine, Louis Stokes VA Medical Center, Cleveland, OH 44106, United States.
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19
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Abstract
A defining feature of HIV-associated neurocognitive disorder (HAND) is the loss of excitatory synaptic connections. Synaptic changes that occur during exposure to HIV appear to result, in part, from a homeostatic scaling response. Here we discuss the mechanisms of these changes from the perspective that they might be part of a coping mechanism that reduces synapses to prevent excitotoxicity. In transgenic animals expressing the HIV proteins Tat or gp120, the loss of synaptic markers precedes changes in neuronal number. In vitro studies have shown that HIV-induced synapse loss and cell death are mediated by distinct mechanisms. Both in vitro and animal studies suggest that HIV-induced synaptic scaling engages new mechanisms that suppress network connectivity and that these processes might be amenable to therapeutic intervention. Indeed, pharmacological reversal of synapse loss induced by HIV Tat restores cognitive function. In summary, studies indicate that there are temporal, mechanistic and pharmacological features of HIV-induced synapse loss that are consistent with homeostatic plasticity. The increasingly well delineated signaling mechanisms that regulate synaptic scaling may reveal pharmacological targets suitable for normalizing synaptic function in chronic neuroinflammatory states such as HAND.
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Affiliation(s)
- Matthew V Green
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN, 55455, USA
| | - Jonathan D Raybuck
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN, 55455, USA
| | - Xinwen Zhang
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN, 55455, USA
| | - Mariah M Wu
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN, 55455, USA
| | - Stanley A Thayer
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN, 55455, USA.
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20
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Stojanovska V, Miller SL, Hooper SB, Polglase GR. The Consequences of Preterm Birth and Chorioamnionitis on Brainstem Respiratory Centers: Implications for Neurochemical Development and Altered Functions by Inflammation and Prostaglandins. Front Cell Neurosci 2018; 12:26. [PMID: 29449803 PMCID: PMC5799271 DOI: 10.3389/fncel.2018.00026] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 01/17/2018] [Indexed: 11/16/2022] Open
Abstract
Preterm birth is a major cause for neonatal morbidity and mortality, and is frequently associated with adverse neurological outcomes. The transition from intrauterine to extrauterine life at birth is particularly challenging for preterm infants. The main physiological driver for extrauterine transition is the establishment of spontaneous breathing. However, preterm infants have difficulty clearing lung liquid, have insufficient surfactant levels, and underdeveloped lungs. Further, preterm infants have an underdeveloped brainstem, resulting in reduced respiratory drive. These factors facilitate the increased requirement for respiratory support. A principal cause of preterm birth is intrauterine infection/inflammation (chorioamnionitis), and infants with chorioamnionitis have an increased risk and severity of neurological damage, but also demonstrate impaired autoresuscitation capacity and prevalent apnoeic episodes. The brainstem contains vital respiratory centers which provide the neural drive for breathing, but the impact of preterm birth and/or chorioamnionitis on this brain region is not well understood. The aim of this review is to provide an overview of the role and function of the brainstem respiratory centers, and to highlight the proposed mechanisms of how preterm birth and chorioamnionitis may affect central respiratory functions.
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Affiliation(s)
- Vanesa Stojanovska
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, VIC, Australia
| | - Suzanne L Miller
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, VIC, Australia.,Department of Obstetrics and Gynaecology, Monash University and Hudson Institute of Medical Research, Melbourne, VIC, Australia
| | - Stuart B Hooper
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, VIC, Australia.,Department of Obstetrics and Gynaecology, Monash University and Hudson Institute of Medical Research, Melbourne, VIC, Australia
| | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, VIC, Australia.,Department of Obstetrics and Gynaecology, Monash University and Hudson Institute of Medical Research, Melbourne, VIC, Australia
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21
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Short-Term Fructose Feeding Induces Inflammation and Oxidative Stress in the Hippocampus of Young and Adult Rats. Mol Neurobiol 2017; 55:2869-2883. [PMID: 28455700 DOI: 10.1007/s12035-017-0518-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 04/04/2017] [Indexed: 10/19/2022]
Abstract
The drastic increase in the consumption of fructose encouraged the research to focus on its effects on brain physio-pathology. Although young and adults differ largely by their metabolic and physiological profiles, most of the previous studies investigated brain disturbances induced by long-term fructose feeding in adults. Therefore, we investigated whether a short-term consumption of fructose (2 weeks) produces early increase in specific markers of inflammation and oxidative stress in the hippocampus of young and adult rats. After the high-fructose diet, plasma lipopolysaccharide and tumour necrosis factor (TNF)-alpha were found significantly increased in parallel with hippocampus inflammation, evidenced by a significant rise in TNF-alpha and glial fibrillar acidic protein concentrations in both the young and adult groups. The fructose-induced inflammatory condition was associated with brain oxidative stress, as increased levels of lipid peroxidation and nitro-tyrosine were detected in the hippocampus. The degree of activation of the protein kinase B, extracellular signal-regulated kinase 1/2, and insulin receptor substrate 1 pathways found in the hippocampus after fructose feeding indicates that the detrimental effects of the fructose-rich diet might largely depend on age. Mitochondrial function in the hippocampus, together with peroxisome proliferator-activated receptor gamma coactivator 1-alpha content, was found significantly decreased in fructose-treated adult rats. In vitro studies with BV-2 microglial cells confirmed that fructose treatment induces TNF-alpha production as well as oxidative stress. In conclusion, these results suggest that unbalanced diet, rich in fructose, may be highly deleterious in young people as in adults and must be strongly discouraged for the prevention of diet-associated neuroinflammation and neurological diseases.
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22
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Davidson JM, Wong CT, Rai-Bhogal R, Li H, Crawford DA. Prostaglandin E2 elevates calcium in differentiated neuroectodermal stem cells. Mol Cell Neurosci 2016; 74:71-7. [PMID: 27074429 DOI: 10.1016/j.mcn.2016.03.010] [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: 04/16/2015] [Revised: 03/21/2016] [Accepted: 03/31/2016] [Indexed: 01/02/2023] Open
Abstract
Lipid mediator prostaglandin E2 (PGE2) is an endogenous signaling molecule that plays an important role during early development of the nervous system. Abnormalities in the PGE2 signaling pathway have been associated with neurodevelopmental disorders such as autism spectrum disorders. In this study we use ratiometric fura-2AM calcium imaging to show that higher levels of PGE2 elevate intracellular calcium levels in the cell soma and growth cones of differentiated neuroectodermal (NE-4C) stem cells. PGE2 also increased the amplitude of calcium fluctuation in the neuronal growth cones and affected the neurite extension length. In summary, our results show that PGE2 may adversely impact intracellular calcium dynamics in differentiated neuronal cells and possibly affect early development of the nervous system.
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Affiliation(s)
- Jennilee M Davidson
- Neuroscience Graduate Diploma Program, York University, Toronto, ON M3J 1P3, Canada; Department of Biology, York University, Toronto, ON M3J 1P3, Canada
| | - Christine T Wong
- School of Kinesiology and Health Science, York University, Toronto, ON M3J 1P3, Canada; Neuroscience Graduate Diploma Program, York University, Toronto, ON M3J 1P3, Canada
| | - Ravneet Rai-Bhogal
- Neuroscience Graduate Diploma Program, York University, Toronto, ON M3J 1P3, Canada; Department of Biology, York University, Toronto, ON M3J 1P3, Canada
| | - Hongyan Li
- School of Kinesiology and Health Science, York University, Toronto, ON M3J 1P3, Canada
| | - Dorota A Crawford
- School of Kinesiology and Health Science, York University, Toronto, ON M3J 1P3, Canada; Neuroscience Graduate Diploma Program, York University, Toronto, ON M3J 1P3, Canada; Department of Biology, York University, Toronto, ON M3J 1P3, Canada.
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23
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Wang HL, Liu H, Xue ZG, Liao QW, Fang H. Minocycline attenuates post-operative cognitive impairment in aged mice by inhibiting microglia activation. J Cell Mol Med 2016; 20:1632-9. [PMID: 27061744 PMCID: PMC4988280 DOI: 10.1111/jcmm.12854] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 02/26/2016] [Indexed: 11/29/2022] Open
Abstract
Although it is known that isoflurane exposure or surgery leads to post‐operative cognitive dysfunction in aged rodents, there are few clinical interventions and treatments available to prevent this disorder. Minocycline (MINO) produces neuroprotection from several neurodegenerative diseases and various experimental animal models. Therefore, we set out to investigate the effects of MINO pre‐treatment on isoflurane or surgery induced cognitive impairment in aged mice by assessing the hippocampal‐dependent spatial memory performance using the Morris water maze task. Hippocampal tissues were isolated from mice and evaluated by Western blot analysis, immunofluorescence procedures and protein array system. Our results elucidate that MINO down‐regulated the isoflurane‐induced and surgery‐induced enhancement in the protein levels of pro‐inflammatory cytokine tumour necrosis factor alpha, interleukin (IL)‐1β, interferon‐γ and microglia marker Iba‐1, and up‐regulated protein levels of the anti‐inflammatory cytokine IL‐4 and IL‐10. These findings suggest that pre‐treatment with MINO attenuated isoflurane or surgery induced cognitive impairment by inhibiting the overactivation of microglia in aged mice.
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Affiliation(s)
- Hui-Lin Wang
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Hua Liu
- Department of Anesthesiology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhang-Gang Xue
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Qing-Wu Liao
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Hao Fang
- Department of Anesthesiology, Zhongshan Hospital, Fudan University, Shanghai, China.,Department of Anesthesiology, Jinshan Hospital, Fudan University, Shanghai, China
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Cyclooxygenase pathway in modulation of the ventilatory response to hypercapnia by interleukin-1β in rats. Respir Physiol Neurobiol 2015; 209:85-90. [DOI: 10.1016/j.resp.2014.12.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Revised: 12/07/2014] [Accepted: 12/07/2014] [Indexed: 01/08/2023]
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25
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Neuroanatomic and Clinical Correspondences: Acupuncture and Vagus Nerve Stimulation. J Altern Complement Med 2014; 20:233-40. [DOI: 10.1089/acm.2012.1022] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Morris G, Maes M. Oxidative and Nitrosative Stress and Immune-Inflammatory Pathways in Patients with Myalgic Encephalomyelitis (ME)/Chronic Fatigue Syndrome (CFS). Curr Neuropharmacol 2014; 12:168-85. [PMID: 24669210 PMCID: PMC3964747 DOI: 10.2174/1570159x11666131120224653] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 07/12/2013] [Accepted: 11/02/2013] [Indexed: 02/07/2023] Open
Abstract
Myalgic Encephalomyelitis (ME) / Chronic Fatigue Syndrome (CFS) has been classified as a disease of the central nervous system by the WHO since 1969. Many patients carrying this diagnosis do demonstrate an almost bewildering array of biological abnormalities particularly the presence of oxidative and nitrosative stress (O&NS) and a chronically activated innate immune system. The proposal made herein is that once generated chronically activated O&NS and immune-inflammatory pathways conspire to generate a multitude of self-sustaining and self-amplifying pathological processes which are associated with the onset of ME/CFS. Sources of continuous activation of O&NS and immune-inflammatory pathways in ME/CFS are chronic, intermittent and opportunistic infections, bacterial translocation, autoimmune responses, mitochondrial dysfunctions, activation of the Toll-Like Receptor Radical Cycle, and decreased antioxidant levels. Consequences of chronically activated O&NS and immune-inflammatory pathways in ME/CFS are brain disorders, including neuroinflammation and brain hypometabolism / hypoperfusion, toxic effects of nitric oxide and peroxynitrite, lipid peroxidation and oxidative damage to DNA, secondary autoimmune responses directed against disrupted lipid membrane components and proteins, mitochondrial dysfunctions with a disruption of energy metabolism (e.g. compromised ATP production) and dysfunctional intracellular signaling pathways. The interplay between all of these factors leads to self-amplifying feed forward loops causing a chronic state of activated O&NS, immune-inflammatory and autoimmune pathways which may sustain the disease.
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Affiliation(s)
| | - Michael Maes
- Department of Psychiatry, Chulalongkorn University, Bangkok, Thailand ; Department of Psychiatry, Deakin University, Geelong, Australia
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Morris G, Maes M. Mitochondrial dysfunctions in myalgic encephalomyelitis/chronic fatigue syndrome explained by activated immuno-inflammatory, oxidative and nitrosative stress pathways. Metab Brain Dis 2014; 29:19-36. [PMID: 24557875 DOI: 10.1007/s11011-013-9435-x] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2013] [Accepted: 08/22/2013] [Indexed: 02/07/2023]
Abstract
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/cfs) is classified by the World Health Organization as a disorder of the central nervous system. ME/cfs is an neuro-immune disorder accompanied by chronic low-grade inflammation, increased levels of oxidative and nitrosative stress (O&NS), O&NS-mediated damage to fatty acids, DNA and proteins, autoimmune reactions directed against neoantigens and brain disorders. Mitochondrial dysfunctions have been found in ME/cfs, e.g. lowered ATP production, impaired oxidative phosphorylation and mitochondrial damage. This paper reviews the pathways that may explain mitochondrial dysfunctions in ME/cfs. Increased levels of pro-inflammatory cytokines, such as interleukin-1 and tumor necrosis factor-α, and elastase, and increased O&NS may inhibit mitochondrial respiration, decrease the activities of the electron transport chain and mitochondrial membrane potential, increase mitochondrial membrane permeability, interfere with ATP production and cause mitochondrial shutdown. The activated O&NS pathways may additionally lead to damage of mitochondrial DNA and membranes thus decreasing membrane fluidity. Lowered levels of antioxidants, zinc and coenzyme Q10, and ω3 polyunsaturated fatty acids in ME/cfs may further aggravate the activated immuno-inflammatory and O&NS pathways. Therefore, it may be concluded that immuno-inflammatory and O&NS pathways may play a role in the mitochondrial dysfunctions and consequently the bioenergetic abnormalities seen in patients with ME/cfs. Defects in ATP production and the electron transport complex, in turn, are associated with an elevated production of superoxide and hydrogen peroxide in mitochondria creating adaptive and synergistic damage. It is argued that mitochondrial dysfunctions, e.g. lowered ATP production, may play a role in the onset of ME/cfs symptoms, e.g. fatigue and post exertional malaise, and may explain in part the central metabolic abnormalities observed in ME/cfs, e.g. glucose hypometabolism and cerebral hypoperfusion.
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28
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Wang G, Sarkar P, Peterson JR, Anrather J, Pierce JP, Moore JM, Feng J, Zhou P, Milner TA, Pickel VM, Iadecola C, Davisson RL. COX-1-derived PGE2 and PGE2 type 1 receptors are vital for angiotensin II-induced formation of reactive oxygen species and Ca(2+) influx in the subfornical organ. Am J Physiol Heart Circ Physiol 2013; 305:H1451-61. [PMID: 24014678 DOI: 10.1152/ajpheart.00238.2013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Regulation of blood pressure by angiotensin II (ANG II) is a process that involves the reactive oxygen species (ROS) and calcium. We have shown that ANG-II type 1 receptor (AT1R) and prostaglandin E2 (PGE2) type 1 receptors (EP1R) are required in the subfornical organ (SFO) for ROS-mediated hypertension induced by slow-pressor ANG-II infusion. However, the signaling pathway associated with this process remains unclear. We sought to determine mechanisms underlying the ANG II-induced ROS and calcium influx in mouse SFO cells. Ultrastructural studies showed that cyclooxygenase 1 (COX-1) codistributes with AT1R in the SFO, indicating spatial proximity. Functional studies using SFO cells revealed that ANG II potentiated PGE2 release, an effect dependent on AT1R, phospholipase A2 (PLA2) and COX-1. Furthermore, both ANG II and PGE2 increased ROS formation. While the increase in ROS initiated by ANG II, but not PGE2, required the activation of the AT1R/PLA2/COX-1 pathway, both ANG II and PGE2 were dependent on EP1R and Nox2 as downstream effectors. Finally, ANG II potentiated voltage-gated L-type Ca(2+) currents in SFO neurons via the same signaling pathway required for PGE2 production. Blockade of EP1R and Nox2-derived ROS inhibited ANG II and PGE2-mediated Ca(2+) currents. We propose a mechanism whereby ANG II increases COX-1-derived PGE2 through the AT1R/PLA2 pathway, which promotes ROS production by EP1R/Nox2 signaling in the SFO. ANG II-induced ROS are coupled with Ca(2+) influx in SFO neurons, which may influence SFO-mediated sympathoexcitation. Our findings provide the first evidence of a spatial and functional framework that underlies ANG-II signaling in the SFO and reveal novel targets for antihypertensive therapies.
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Affiliation(s)
- Gang Wang
- The Brain and Mind Research Institute, Weill Cornell Medical College, New York, New York
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Norden DM, Godbout JP. Review: microglia of the aged brain: primed to be activated and resistant to regulation. Neuropathol Appl Neurobiol 2013; 39:19-34. [PMID: 23039106 DOI: 10.1111/j.1365-2990.2012.01306.x] [Citation(s) in RCA: 562] [Impact Index Per Article: 51.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Accepted: 09/25/2012] [Indexed: 01/08/2023]
Abstract
Innate immunity within the central nervous system (CNS) is primarily provided by resident microglia. Microglia are pivotal in immune surveillance and also facilitate the co-ordinated responses between the immune system and the brain. For example, microglia interpret and propagate inflammatory signals that are initiated in the periphery. This transient microglial activation helps mount the appropriate physiological and behavioural response following peripheral infection. With normal ageing, however, microglia develop a more inflammatory phenotype. For instance, in several models of ageing there are increased pro-inflammatory cytokines in the brain and increased expression of inflammatory receptors on microglia. This increased inflammatory status of microglia with ageing is referred to as primed, reactive or sensitized. A modest increase in the inflammatory profile of the CNS and altered microglial function in ageing has behavioural and cognitive consequences. Nonetheless, there are major differences in microglial biology between young and old age when the immune system is challenged and microglia are activated. In this context, microglial activation is amplified and prolonged in the aged brain compared with adults. The cause of this amplified microglial activation may be related to impairments in several key regulatory systems with age that make it more difficult to resolve microglial activation. The consequences of impaired regulation and microglial hyper-activation following immune challenge are exaggerated neuroinflammation, sickness behaviour, depressive-like behaviour and cognitive deficits. Therefore the purpose of this review is to discuss the current understanding of age-associated microglial priming, consequences of priming and reactivity, and the impairments in regulatory systems that may underlie these age-related deficits.
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Affiliation(s)
- D M Norden
- Department of Neuroscience, The Ohio State University, Columbus, OH, USA
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30
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Morris G, Anderson G, Galecki P, Berk M, Maes M. A narrative review on the similarities and dissimilarities between myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and sickness behavior. BMC Med 2013; 11:64. [PMID: 23497361 PMCID: PMC3751187 DOI: 10.1186/1741-7015-11-64] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 03/08/2013] [Indexed: 12/14/2022] Open
Abstract
It is of importance whether myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a variant of sickness behavior. The latter is induced by acute infections/injury being principally mediated through proinflammatory cytokines. Sickness is a beneficial behavioral response that serves to enhance recovery, conserves energy and plays a role in the resolution of inflammation. There are behavioral/symptomatic similarities (for example, fatigue, malaise, hyperalgesia) and dissimilarities (gastrointestinal symptoms, anorexia and weight loss) between sickness and ME/CFS. While sickness is an adaptive response induced by proinflammatory cytokines, ME/CFS is a chronic, disabling disorder, where the pathophysiology is related to activation of immunoinflammatory and oxidative pathways and autoimmune responses. While sickness behavior is a state of energy conservation, which plays a role in combating pathogens, ME/CFS is a chronic disease underpinned by a state of energy depletion. While sickness is an acute response to infection/injury, the trigger factors in ME/CFS are less well defined and encompass acute and chronic infections, as well as inflammatory or autoimmune diseases. It is concluded that sickness behavior and ME/CFS are two different conditions.
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Affiliation(s)
- Gerwyn Morris
- Tir Na Nog, Bryn Road Seaside 87, Llanelli, SA152LW, UK
| | - George Anderson
- CRC Clinical Research Centre/Communications, Laurel Street 57, Glasgow, G11 7QT,UK
| | - Piotr Galecki
- Department of Adult Psychiatry, Medical University of Lodz, Aleksandrowska 159, Lodz, 91229, Poland
| | - Michael Berk
- Barwon Health, School of Medicine, Deakin University, PO Box 291, Geelong, 3220, Australia
- Orygen Youth Health Research Centre, Poplar Road 35, Parkville, 3052, Australia
- Centre of Youth Mental Health, University of Melbourne, Poplar Road 35, Parkville, 3052, Australia
- The Florey Institute for Neuroscience and Mental Health, University of Melbourne, Kenneth Myer Building, Royal Parade 30, Parkville, 3052, Australia
- Department of Psychiatry, University of Melbourne, Level 1 North, Main Block, Royal Melbourne Hospital, Parkville, 3052, Australia
| | - Michael Maes
- Barwon Health, School of Medicine, Deakin University, PO Box 291, Geelong, 3220, Australia
- Department of Psychiatry, Chulalongkorn University, Rama 4 Road 1873, Pathumwan, Bangkok, 10330, Thailand
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Abstract
BACKGROUND Apnea associated with infection and inflammation is a major medical concern in preterm infants. Prostaglandin E(2) (PGE(2)) serves as a critical mediator between infection and apnea. We hypothesize that alteration of the microsomal PGE synthase-1 (mPGES-1) PGE(2) pathway influences respiratory control and response to hypoxia. METHODS Nine-d-old wild-type (WT) mice, mPGES-1 heterozygote (mPGES-1(+/-)), and mPGES-1 knockout (mPGES-1(-/-)) mice were used. Respiration was investigated in mice using flow plethysmography after the mice received either interleukin-1β (IL-1β) (10 µg/kg) or saline. Mice were subjected to a period of normoxia, subsequent exposure to hyperoxia, and finally either moderate (5 min) or severe hypoxia (until 1 min after last gasp). RESULTS IL-1β worsened survival in WT mice but not in mice with reduced or no mPGES-1. Reduced expression of mPGES-1 prolonged gasping duration and increased the number of gasps during hypoxia. Response to intracerebroventricular PGE(2) was not dependent on mPGES-1 expression. CONCLUSION Activation of mPGES-1 is involved in the rapid and vital response to severe hypoxia as well as inflammation. Attenuation of mPGES-1 appears to have no detrimental effects, yet prolongs autoresuscitation efforts and improves survival. Consequently, inhibition of the mPGES-1 pathway may serve as a potential therapeutic target for the treatment of apnea and respiratory disorders.
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32
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Mishra A, Kim HJ, Shin AH, Thayer SA. Synapse loss induced by interleukin-1β requires pre- and post-synaptic mechanisms. J Neuroimmune Pharmacol 2012; 7:571-8. [PMID: 22311599 DOI: 10.1007/s11481-012-9342-7] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 01/13/2012] [Indexed: 01/31/2023]
Abstract
Interleukin-1β (IL-1β) is an inflammatory cytokine that exerts marked effects on neuronal function and survival. Here we examined the effects of IL-1β on synapses between rat hippocampal neurons in culture using an imaging-based assay to quantify clusters of the scaffolding protein postsynaptic density 95 fused to green fluorescent protein. Treatment with IL-1β for 24 h induced a 23 ± 3% loss in the number of synaptic sites. Pharmacological studies indicated that synapse loss was mediated by the IL-1 receptor with subsequent activation of two pathways. COX2-mediated prostaglandin production and postsynaptic activation of a Src family tyrosine kinase were required. Presynaptic release of glutamate with subsequent activation of NMDA receptors was necessary for IL-1β-induced synapse loss. Neither Src activation nor prostaglandin E2 (PGE2) application alone was sufficient to reduce the number of synapses. However, in cells expressing constitutively active or pharmacologically activated Src, PGE2 induced synapse loss. Thus, IL-1β reduces the number of synaptic connections by simultaneously activating multiple pathways that require both pre- and post-synaptic activity. These results highlight targets that may prove important for pharmacotherapy of neuroinflammatory disease.
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Affiliation(s)
- Anjuli Mishra
- Department of Pharmacology, University of Minnesota Medical School, 321 Church Street SE, 6-120 Jackson Hall, Minneapolis, MN 55455, USA
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33
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Corona AW, Fenn AM, Godbout JP. Cognitive and behavioral consequences of impaired immunoregulation in aging. J Neuroimmune Pharmacol 2011; 7:7-23. [PMID: 21932047 DOI: 10.1007/s11481-011-9313-4] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Accepted: 09/07/2011] [Indexed: 11/29/2022]
Abstract
A hallmark of the aged immune system is impaired immunoregulation of the innate and adaptive immune system in the periphery and also in the central nervous system (CNS). Impaired immunoregulation may predispose older individuals to an increased frequency of peripheral infections with concomitant cognitive and behavioral complications. Thus, normal aging is hypothesized to alter the highly coordinated interactions between the immune system and the brain. In support of this notion, mounting evidence in rodent models indicate that the increased inflammatory status of the brain is associated with increased reactivity of microglia, the innate immune cells of the CNS. Understanding how immunity is affected with age is important because CNS immune cells play an integral role in propagating inflammatory signals that are initiated in the periphery. Increased reactivity of microglia sets the stage for an exaggerated inflammatory cytokine response following activation of the peripheral innate immune system that is paralleled by prolonged sickness, depressive-like complications and cognitive impairment. Moreover, amplified neuroinflammation negatively affects several aspects of neural plasticity (e.g., neurogenesis, long-term potentiation, and dendritic morphology) that can contribute to the severity of neurological complications. The purpose of this review is to discuss several key peripheral and central immune changes that impair the coordinated response between the immune system and the brain and result in behavioral and cognitive deficits.
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Affiliation(s)
- Angela W Corona
- Department of Neuroscience, The Ohio State University, Columbus, OH 43210, USA
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34
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An inflammatory pathway to apnea and autonomic dysregulation. Respir Physiol Neurobiol 2011; 178:449-57. [DOI: 10.1016/j.resp.2011.06.026] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 06/29/2011] [Accepted: 06/29/2011] [Indexed: 01/04/2023]
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35
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Kim HJ, Shin AH, Thayer SA. Activation of cannabinoid type 2 receptors inhibits HIV-1 envelope glycoprotein gp120-induced synapse loss. Mol Pharmacol 2011; 80:357-66. [PMID: 21670103 DOI: 10.1124/mol.111.071647] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
HIV-1 infection of the central nervous system is associated with dendritic and synaptic damage that correlates with cognitive decline in patients with HIV-1-associated dementia (HAD). HAD is due in part to the release of viral proteins from infected cells. Because cannabinoids modulate neurotoxic and inflammatory processes, we investigated their effects on changes in synaptic connections induced by the HIV-1 envelope glycoprotein gp120. Morphology and synapses between cultured hippocampal neurons were visualized by confocal imaging of neurons expressing DsRed2 and postsynaptic density protein 95 fused to green fluorescent protein (PSD95-GFP). Twenty-four-hour treatment with gp120 IIIB decreased the number of PSD95-GFP puncta by 37 ± 4%. The decrease was concentration-dependent (EC₅₀ = 153 ± 50 pM). Synapse loss preceded cell death as defined by retention of DsRed2 fluorescence gp120 activated CXCR4 on microglia to evoke interleukin-1β (IL-1β) release. Pharmacological studies determined that sequential activation of CXCR4, the IL-1β receptor, and the N-methyl-d-aspartate receptor was required. Expression of alternative reading frame polypeptide, which inhibits the ubiquitin ligase murine double minute 2, protected synapses, implicating the ubiquitin-proteasome pathway. Cannabimimetic drugs are of particular relevance to HAD because of their clinical and illicit use in patients with AIDS. The cannabinoid receptor full agonist [(R)-(+)-[2,3-dihydro-5-methyl-3[(4-morpholinyl)methyl]pyrrolo[1,2,3-de]-1,4-benzoxazinyl]-(1-naphthalenyl) methanone mesylate salt] (Win55,212-2) inhibited gp120-induced IL-1β production and synapse in a manner reversed by a cannabinoid type 2 receptor antagonist. In contrast, Win55,212-2 did not inhibit synapse loss elicited by exposure to the HIV-1 protein Tat. These results indicate that cannabinoids prevent the impairment of network function produced by gp120 and, thus, might have therapeutic potential in HAD.
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Affiliation(s)
- Hee Jung Kim
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
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36
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Gresham K, Boyer B, Mayer C, Foglyano R, Martin R, Wilson CG. Airway inflammation and central respiratory control: results from in vivo and in vitro neonatal rat. Respir Physiol Neurobiol 2011; 178:414-21. [PMID: 21609789 DOI: 10.1016/j.resp.2011.05.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 05/08/2011] [Accepted: 05/10/2011] [Indexed: 11/16/2022]
Abstract
In infants, respiratory infection elicits tachypnea. To begin to evaluate the role of brainstem cytokine expression in modulation of breathing pattern changes, we compared the pattern generated after endotracheal instillation of lipopolysaccharide (LPS) in in vivo rat pups to local pro-inflammatory cytokine injection in the nucleus tractus solitarius (nTS) in an in vitro en bloc brainstem spinal cord preparation. We hypothesized that both challenges would elicit similar changes in patterning of respiration. In anesthetized, spontaneously breathing rat pups, lipopolysaccharide (LPS) or saline was instilled in the airway of urethane-anesthetized rats (postnatal days 10-11). We recorded diaphragm EMG over the subsequent 2h and saw a 20-30% decrease in interburst interval (Te) at 20-80min post-injection in LPS-instilled animals with no significant change in Ti. In contrast, IL-1β injections into the nTS of en bloc in vitro brainstem-spinal cord preparations from 0 to 5 day-old pups maintained Ti and caused an increase in Te as early as 20min later, decreasing frequency for 80-120min after injection. Our results suggest that the neonatal respiratory response to the cytokine IL-1β mediated inflammatory response depends on the site of the inflammatory stimulus and that the direct effect of IL-1β in the nTS is to slow rather than increase rate.
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Affiliation(s)
- Kenneth Gresham
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH 44106, United States
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37
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Tamiji J, Crawford DA. The neurobiology of lipid metabolism in autism spectrum disorders. Neurosignals 2011; 18:98-112. [PMID: 21346377 DOI: 10.1159/000323189] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Accepted: 11/29/2010] [Indexed: 01/17/2023] Open
Abstract
Autism is a neurodevelopmental disorder characterized by impairments in communication and reciprocal social interaction, coupled with repetitive behavior, which typically manifests by 3 years of age. Multiple genes and early exposure to environmental factors are the etiological determinants of the disorder that contribute to variable expression of autism-related traits. Increasing evidence indicates that altered fatty acid metabolic pathways may affect proper function of the nervous system and contribute to autism spectrum disorders. This review provides an overview of the reported abnormalities associated with the synthesis of membrane fatty acids in individuals with autism as a result of insufficient dietary supplementation or genetic defects. Moreover, we discuss deficits associated with the release of arachidonic acid from the membrane phospholipids and its subsequent metabolism to bioactive prostaglandins via phospholipase A(2)-cyclooxygenase biosynthetic pathway in autism spectrum disorders. The existing evidence for the involvement of lipid neurobiology in the pathology of neurodevelopmental disorders such as autism is compelling and opens up an interesting possibility for further investigation of this metabolic pathway.
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Affiliation(s)
- Javaneh Tamiji
- Department of Biology, York University, Toronto, Ont., Canada
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38
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Prostaglandin E2 and misoprostol induce neurite retraction in Neuro-2a cells. Biochem Biophys Res Commun 2010; 398:450-6. [DOI: 10.1016/j.bbrc.2010.06.098] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Accepted: 06/24/2010] [Indexed: 11/23/2022]
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Gautron L, Layé S. Neurobiology of inflammation-associated anorexia. Front Neurosci 2010; 3:59. [PMID: 20582290 PMCID: PMC2858622 DOI: 10.3389/neuro.23.003.2009] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Accepted: 12/16/2009] [Indexed: 12/23/2022] Open
Abstract
Compelling data demonstrate that inflammation-associated anorexia directly results from the action of pro-inflammatory factors, primarily cytokines and prostaglandins E2, on the nervous system. For instance, the aforementioned pro-inflammatory factors can stimulate the activity of peripheral sensory neurons, and induce their own de novo synthesis and release into the brain parenchyma and cerebrospinal fluid. Ultimately, it results in the mobilization of a specific neural circuit that shuts down appetite. The present article describes the different cell groups and neurotransmitters involved in inflammation-associated anorexia and examines how they interact with neural systems regulating feeding such as the melanocortin system. A better understanding of the neurobiological mechanisms underlying inflammation-associated anorexia will help to develop appetite stimulants for cancer and AIDS patients.
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Affiliation(s)
- Laurent Gautron
- The University of Texas Southwestern Medical Center Dallas, TX, USA
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40
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DeBoer MD. Update on melanocortin interventions for cachexia: progress toward clinical application. Nutrition 2009; 26:146-51. [PMID: 20004082 DOI: 10.1016/j.nut.2009.07.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Accepted: 07/07/2009] [Indexed: 11/24/2022]
Abstract
Cachexia is a devastating syndrome of body wasting that is associated with multiple common chronic diseases including cancer, chronic kidney disease, and chronic heart failure. These underlying diseases are associated with increased levels of inflammatory cytokines and result in anorexia, increased resting energy expenditure, and loss of fat and lean body mass. Prior experiments have implicated the central melanocortin system in the hypothalamus with the propagation of these symptoms of cachexia. Pharmacologic blockade of this system using melanocortin antagonists causes attenuation of the signs of cachexia in laboratory models. Recent advances in our knowledge of this disease process have involved further elucidation of the pathophysiology of melanocortin activation and demonstration of the efficacy of melanocortin antagonists in new models of cachexia, including cardiac cachexia. In addition, small molecule antagonists of the melanocortin-4 receptor continue to be introduced, including ones with oral bioavailability. These developments generate optimism that melanocortin antagonism will be used to treat humans with disease-associated cachexia. However, to date, human application has remained elusive and it is unclear when we will know whether humans with cachexia would benefit from treatment with these compounds.
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Affiliation(s)
- Mark Daniel DeBoer
- Division of Pediatric Endocrinology, University of Virginia, Charlottesville, Virginia, USA.
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41
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Darmani NA, Ray AP. Evidence for a re-evaluation of the neurochemical and anatomical bases of chemotherapy-induced vomiting. Chem Rev 2009; 109:3158-99. [PMID: 19522506 DOI: 10.1021/cr900117p] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Nissar A Darmani
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, California 91766-1854, USA.
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Wynne AM, Henry CJ, Godbout JP. Immune and behavioral consequences of microglial reactivity in the aged brain. Integr Comp Biol 2009; 49:254-66. [PMID: 21665818 DOI: 10.1093/icb/icp009] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Bidirectional communication between the immune system and the brain is essential for mounting the appropriate immunological, physiological, and behavioral responses to immune activation. Aging, however, may impair this important bi-directional interaction. In support of this notion, peripheral infection in the elderly is associated with an increased frequency of behavioral and cognitive complications. Recent findings in animal models of aging and neurodegenerative disease indicate that microglia, innate immune cells of the brain, become primed or reactive. Understanding age- and disease-associated alterations in microglia is important because glia (microglia and astrocytes) play an integral role in propagating inflammatory signals that are initiated in the periphery. In this capacity, brain glia produce inflammatory cytokines that target neuronal substrates and elicit a sickness-behavior syndrome that is normally beneficial to the host organism. Increased reactivity of microglia sets the stage for an exaggerated neuroinflammatory cytokine response following activation of the peripheral innate immune system, which may underlie subsequent long-lasting behavioral and cognitive deficits. In support of this premise, recent findings indicate that stimulation of the peripheral immune system in aged rodents causes exaggerated neuroinflammation that is paralleled by cognitive impairment, prolonged sickness, and depressive-like complications. Therefore, the purpose of this review is to discuss the new evidence that age-associated priming of microglia could play a pathophysiological role in exaggerated behavioral and cognitive sequelae to peripheral infection.
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Affiliation(s)
- Angela M Wynne
- Department of Molecular Virology, Immunology and Medical Genetics, The Ohio State University, Columbus, OH 43210, USA
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DeBoer MD, Scarlett JM, Levasseur PR, Grant WF, Marks DL. Administration of IL-1beta to the 4th ventricle causes anorexia that is blocked by agouti-related peptide and that coincides with activation of tyrosine-hydroxylase neurons in the nucleus of the solitary tract. Peptides 2009; 30:210-8. [PMID: 19028534 PMCID: PMC2853249 DOI: 10.1016/j.peptides.2008.10.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2008] [Revised: 10/28/2008] [Accepted: 10/28/2008] [Indexed: 12/19/2022]
Abstract
Inflammation-associated cachexia is associated with multiple chronic diseases and involves activation of appetite regulating centers in the arcuate nucleus of the hypothalamus (ARH). The nucleus of the solitary tract (NTS) in the brainstem has also been implicated as an important nucleus involved in appetite regulation. We set out to determine whether the NTS may be involved in inflammation-associated anorexia by injecting IL-1 beta into the 4th ventricle and assessing food intake and NTS neuronal activation. Injection of IL-1 beta produced a decrease in food intake at 3 and 12h after injection which was ameliorated at the 12h time point by a sub-threshold dose of agouti-related peptide (AgRP). Investigation into neuron types in the NTS revealed that IL-1 beta injection was associated with an increase in c-Fos activity in NTS neurons expressing tyrosine hydroxylase (TH). Additionally, injection of IL-1 beta into the 4th ventricle did not produce c-Fos activation of neurons expressing pro-opiomelanocortin (POMC) in the ARH, cells known to be involved in producing anorexia in response to systemic inflammation. Double-label in situ hybridization revealed that TH neurons did not express IL-1 receptor I (IL1-RI) transcript, demonstrating that c-Fos activation of TH neurons in this setting was not via direct stimulation of IL-1 beta on TH neurons themselves. We conclude that IL-1 beta injection into the 4th ventricle produces anorexia and is accompanied by an increase in activation in TH neurons in the NTS. This provides evidence that the brainstem may be an important mediator of anorexia in the setting of inflammation.
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Affiliation(s)
- Mark D. DeBoer
- Department of Pediatrics, Oregon Health & Science University, United States
| | - Jarrad M. Scarlett
- Department of Pediatrics, Oregon Health & Science University, United States
| | - Peter R. Levasseur
- Department of Pediatrics, Oregon Health & Science University, United States
| | - Wilmon F. Grant
- Department of Pediatrics, Oregon Health & Science University, United States
| | - Daniel L. Marks
- Department of Pediatrics, Oregon Health & Science University, United States
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