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Izquierdo-Altarejos P, Arenas YM, Martínez-García M, Vázquez L, Mincheva G, Doverskog M, Blackburn TP, Bohnen NI, Llansola M, Felipo V. Golexanolone reduces glial activation in the striatum and improves non-motor and some motor alterations in a rat model of Parkinson's disease. Front Aging Neurosci 2024; 16:1417938. [PMID: 38974902 PMCID: PMC11224447 DOI: 10.3389/fnagi.2024.1417938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Accepted: 06/03/2024] [Indexed: 07/09/2024] Open
Abstract
Background Parkinson's disease (PD) affects more than 6 million people worldwide. Along with motor impairments, patients and animal models exhibiting PD symptoms also experience cognitive impairment, fatigue, anxiety, and depression. Currently, there are no drugs available for PD that alter the progression of the disease. A body of evidence suggests that increased GABA levels contribute to the reduced expression of tyrosine hydroxylase (TH) and accompanying behavioral deficits. TH expression may be restored by blocking GABAA receptors. We hypothesized that golexanolone (GR3027), a well-tolerated GABAA receptor-modulating steroid antagonist (GAMSA), may improve Parkinson's symptoms in a rat model of PD. Objectives The aims of this study were to assess whether golexanolone can ameliorate motor and non-motor symptoms in a rat model of PD and to identify some underlying mechanisms. Methods We used the unilateral 6-OHDA rat model of PD. The golexanolone treatment started 4 weeks after surgery. Motor symptoms were assessed using Motorater and CatWalk tests. We also analyzed fatigue (using a treadmill test), anhedonia (via the sucrose preference test), anxiety (with an open field test), and short-term memory (using a Y maze). Glial activation and key proteins involved in PD pathogenesis were analyzed using immunohistochemistry and Western blot. Results Rats with PD showed motor incoordination and impaired locomotor gait, increased fatigue, anxiety, depression, and impaired short-term memory. Golexanolone treatment led to improvements in motor incoordination, certain aspects of locomotor gait, fatigue, anxiety, depression, and short-term memory. Notably, golexanolone reduced the activation of microglia and astrocytes, mitigated TH loss at 5 weeks after surgery, and prevented the increase of α-synuclein levels at 10 weeks. Conclusions Golexanolone may be useful in improving both motor and non-motor symptoms that adversely affect the quality of life in PD patients, such as anxiety, depression, fatigue, motor coordination, locomotor gait, and certain cognitive alterations.
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Affiliation(s)
| | - Yaiza M. Arenas
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Mar Martínez-García
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Lola Vázquez
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Gergana Mincheva
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | | | | | - Nicolaas I. Bohnen
- Department of Radiology, University of Michigan, Ann Arbor, MI, United States
- Neurology Service and GRECC, Veterans Administration Ann Arbor Healthcare System, Ann Arbor, MI, United States
- Morris K. Udall Center of Excellence for Parkinson's Disease Research, University of Michigan, Ann Arbor, MI, United States
- Parkinson's Foundation Center of Excellence, University of Michigan, Ann Arbor, MI, United States
| | - Marta Llansola
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
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Bäckström T, Doverskog M, Blackburn TP, Scharschmidt BF, Felipo V. Allopregnanolone and its antagonist modulate neuroinflammation and neurological impairment. Neurosci Biobehav Rev 2024; 161:105668. [PMID: 38608826 DOI: 10.1016/j.neubiorev.2024.105668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 03/18/2024] [Accepted: 04/07/2024] [Indexed: 04/14/2024]
Abstract
Neuroinflammation accompanies several brain disorders, either as a secondary consequence or as a primary cause and may contribute importantly to disease pathogenesis. Neurosteroids which act as Positive Steroid Allosteric GABA-A receptor Modulators (Steroid-PAM) appear to modulate neuroinflammation and their levels in the brain may vary because of increased or decreased local production or import from the systemic circulation. The increased synthesis of steroid-PAMs is possibly due to increased expression of the mitochondrial cholesterol transporting protein (TSPO) in neuroinflammatory tissue, and reduced production may be due to changes in the enzymatic activity. Microglia and astrocytes play an important role in neuroinflammation, and their production of inflammatory mediators can be both activated and inhibited by steroid-PAMs and GABA. What is surprising is the finding that both allopregnanolone, a steroid-PAM, and golexanolone, a novel GABA-A receptor modulating steroid antagonist (GAMSA), can inhibit microglia and astrocyte activation and normalize their function. This review focuses on the role of steroid-PAMs in neuroinflammation and their importance in new therapeutic approaches to CNS and liver disease.
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Affiliation(s)
| | | | | | | | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
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3
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Llansola M. Preface for the Vicente Felipo Honorary Issue of Neurochemical Research. Neurochem Res 2024; 49:1421-1426. [PMID: 38641758 DOI: 10.1007/s11064-024-04139-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/21/2024]
Affiliation(s)
- Marta Llansola
- Laboratory of Neurobiology, Principe Felipe Research Center, Valencia, Spain.
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Berríos-Cárcamo P, Núñez S, Castañeda J, Gallardo J, Bono MR, Ezquer F. Two-Month Voluntary Ethanol Consumption Promotes Mild Neuroinflammation in the Cerebellum but Not in the Prefrontal Cortex, Hippocampus, or Striatum of Mice. Int J Mol Sci 2024; 25:4173. [PMID: 38673763 PMCID: PMC11050159 DOI: 10.3390/ijms25084173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 03/29/2024] [Accepted: 04/05/2024] [Indexed: 04/28/2024] Open
Abstract
Chronic ethanol exposure often triggers neuroinflammation in the brain's reward system, potentially promoting the drive for ethanol consumption. A main marker of neuroinflammation is the microglia-derived monocyte chemoattractant protein 1 (MCP1) in animal models of alcohol use disorder in which ethanol is forcefully given. However, there are conflicting findings on whether MCP1 is elevated when ethanol is taken voluntarily, which challenges its key role in promoting motivation for ethanol consumption. Here, we studied MCP1 mRNA levels in areas implicated in consumption motivation-specifically, the prefrontal cortex, hippocampus, and striatum-as well as in the cerebellum, a brain area highly sensitive to ethanol, of C57BL/6 mice subjected to intermittent and voluntary ethanol consumption for two months. We found a significant increase in MCP1 mRNA levels in the cerebellum of mice that consumed ethanol compared to controls, whereas no significant changes were observed in the prefrontal cortex, hippocampus, or striatum or in microglia isolated from the hippocampus and striatum. To further characterize cerebellar neuroinflammation, we measured the expression changes in other proinflammatory markers and chemokines, revealing a significant increase in the proinflammatory microRNA miR-155. Notably, other classical proinflammatory markers, such as TNFα, IL6, and IL-1β, remained unaltered, suggesting mild neuroinflammation. These results suggest that the onset of neuroinflammation in motivation-related areas is not required for high voluntary consumption in C57BL/6 mice. In addition, cerebellar susceptibility to neuroinflammation may be a trigger to the cerebellar degeneration that occurs after chronic ethanol consumption in humans.
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Affiliation(s)
- Pablo Berríos-Cárcamo
- Center for Regenerative Medicine, Faculty of Medicine, Clínica Alemana-Universidad del Desarrollo, Santiago 7610615, Chile; (J.G.); (F.E.)
| | - Sarah Núñez
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Sede Los Leones 7510602, Chile;
- Centro Ciencia & Vida, Santiago 8580702, Chile
| | - Justine Castañeda
- Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile; (J.C.); (M.R.B.)
| | - Javiera Gallardo
- Center for Regenerative Medicine, Faculty of Medicine, Clínica Alemana-Universidad del Desarrollo, Santiago 7610615, Chile; (J.G.); (F.E.)
| | - María Rosa Bono
- Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile; (J.C.); (M.R.B.)
| | - Fernando Ezquer
- Center for Regenerative Medicine, Faculty of Medicine, Clínica Alemana-Universidad del Desarrollo, Santiago 7610615, Chile; (J.G.); (F.E.)
- Research Center for the Development of Novel Therapeutics Alternatives for Alcohol Use Disorders, Santiago 7610658, Chile
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5
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Llansola M, Arenas YM, Sancho-Alonso M, Mincheva G, Palomares-Rodriguez A, Doverskog M, Izquierdo-Altarejos P, Felipo V. Neuroinflammation alters GABAergic neurotransmission in hyperammonemia and hepatic encephalopathy, leading to motor incoordination. Mechanisms and therapeutic implications. Front Pharmacol 2024; 15:1358323. [PMID: 38560359 PMCID: PMC10978603 DOI: 10.3389/fphar.2024.1358323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 02/29/2024] [Indexed: 04/04/2024] Open
Abstract
Enhanced GABAergic neurotransmission contributes to impairment of motor coordination and gait and of cognitive function in different pathologies, including hyperammonemia and hepatic encephalopathy. Neuroinflammation is a main contributor to enhancement of GABAergic neurotransmission through increased activation of different pathways. For example, enhanced activation of the TNFα-TNFR1-NF-κB-glutaminase-GAT3 pathway and the TNFα-TNFR1-S1PR2-CCL2-BDNF-TrkB pathway in cerebellum of hyperammonemic rats enhances GABAergic neurotransmission. This is mediated by mechanisms affecting GABA synthesizing enzymes GAD67 and GAD65, total and extracellular GABA levels, membrane expression of GABAA receptor subunits, of GABA transporters GAT1 and GAT three and of chloride co-transporters. Reducing neuroinflammation reverses these changes, normalizes GABAergic neurotransmission and restores motor coordination. There is an interplay between GABAergic neurotransmission and neuroinflammation, which modulate each other and altogether modulate motor coordination and cognitive function. In this way, neuroinflammation may be also reduced by reducing GABAergic neurotransmission, which may also improve cognitive and motor function in pathologies associated to neuroinflammation and enhanced GABAergic neurotransmission such as hyperammonemia, hepatic encephalopathy or Parkinson's disease. This provides therapeutic targets that may be modulated to improve cognitive and motor function and other alterations such as fatigue in a wide range of pathologies. As a proof of concept it has been shown that antagonists of GABAA receptors such as bicuculline reduces neuroinflammation and improves cognitive and motor function impairment in rat models of hyperammonemia and hepatic encephalopathy. Antagonists of GABAA receptors are not ideal therapeutic tools because they can induce secondary effects. As a more effective treatment to reduce GABAergic neurotransmission new compounds modulating it by other mechanisms are being developed. Golexanolone reduces GABAergic neurotransmission by reducing the potentiation of GABAA receptor activation by neurosteroids such as allopregnanolone. Golexanolone reduces neuroinflammation and GABAergic neurotransmission in animal models of hyperammonemia, hepatic encephalopathy and cholestasis and this is associated with improvement of fatigue, cognitive impairment and motor incoordination. This type of compounds may be useful therapeutic tools to improve cognitive and motor function in different pathologies associated with neuroinflammation and increased GABAergic neurotransmission.
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Affiliation(s)
- Marta Llansola
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Yaiza M. Arenas
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - María Sancho-Alonso
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Gergana Mincheva
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | | | | | | | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
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Gruol DL. The Neuroimmune System and the Cerebellum. CEREBELLUM (LONDON, ENGLAND) 2023:10.1007/s12311-023-01624-3. [PMID: 37950146 DOI: 10.1007/s12311-023-01624-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/20/2023] [Indexed: 11/12/2023]
Abstract
The recognition that there is an innate immune system of the brain, referred to as the neuroimmune system, that preforms many functions comparable to that of the peripheral immune system is a relatively new concept and much is yet to be learned. The main cellular components of the neuroimmune system are the glial cells of the brain, primarily microglia and astrocytes. These cell types preform many functions through secretion of signaling factors initially known as immune factors but referred to as neuroimmune factors when produced by cells of the brain. The immune functions of glial cells play critical roles in the healthy brain to maintain homeostasis that is essential for normal brain function, to establish cytoarchitecture of the brain during development, and, in pathological conditions, to minimize the detrimental effects of disease and injury and promote repair of brain structure and function. However, dysregulation of this system can occur resulting in actions that exacerbate or perpetuate the detrimental effects of disease or injury. The neuroimmune system extends throughout all brain regions, but attention to the cerebellar system has lagged that of other brain regions and information is limited on this topic. This article is meant to provide a brief introduction to the cellular and molecular components of the brain immune system, its functions, and what is known about its role in the cerebellum. The majority of this information comes from studies of animal models and pathological conditions, where upregulation of the system facilitates investigation of its actions.
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Affiliation(s)
- Donna L Gruol
- Neuroscience Department, The Scripps Research Institute, La Jolla, CA, 92037, USA.
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7
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Leone P, Arenas YM, Balzano T, Mincheva G, Martinez-Garcia M, Montoliu C, Llansola M, Felipo V. Patients who died with steatohepatitis or liver cirrhosis show neuroinflammation and neuronal loss in hippocampus. Eur J Neurol 2023; 30:3032-3046. [PMID: 37340928 DOI: 10.1111/ene.15935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 06/08/2023] [Accepted: 06/13/2023] [Indexed: 06/22/2023]
Abstract
BACKGROUND Neuroinflammation in the cerebral cortex of patients who died with liver cirrhosis and neuroinflammation, and neuronal death in the cerebellum of patients who died with steatohepatitis or cirrhosis, were reported. Hippocampal neuroinflammation could contribute to cognitive decline in patients with liver disease, but this has yet to be studied. The study aims were to assess if hippocampus from patients who died with steatohepatitis or cirrhosis showed: (i) glial activation, (ii) altered cytokine content, (iii) immune cell infiltration, (iv) neuronal apoptosis and (v) neuronal loss. METHODS Post-mortem hippocampus was obtained from 6 controls, 19 patients with steatohepatitis (SH) and 4 patients with liver cirrhosis. SH patients were divided into SH1 (n = 9), SH2 (n = 6) and SH3 (n = 4) groups depending on disease severity. Glial activation, IL-1β and TNFα content, CD4 lymphocyte and monocyte infiltration, neuronal apoptosis and neuronal loss were analyzed by immunohistochemistry. RESULTS Patients who died in SH1 showed astrocyte activation, whereas those who died in SH2 also showed microglial activation, CD4 lymphocyte and monocyte infiltration, neuronal apoptosis and neuronal loss. These changes remained in patients in SH3, who also showed increased IL-1β and TNFα. Patients who died of liver cirrhosis did not show CD4 lymphocyte infiltration, neuronal apoptosis or increase in TNFα, but still showed glial activation, increased IL-1β and neuronal loss. CONCLUSIONS Patients with steatohepatitis showed glial activation, immune cell infiltration, apoptosis and neuronal loss. Glial activation and neuronal loss remained in cirrhotic patients. This may explain the irreversibility of some cognitive alterations in hepatic encephalopathy. Cognitive reserve may contribute to different grades of cognitive impairment despite similar neuronal loss.
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Affiliation(s)
- Paola Leone
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Yaiza M Arenas
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Tiziano Balzano
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
- Centro Integral de Neurociencias, Hospital Universitario Puerta del Sur CINAC, Madrid, Spain
| | - Gergana Mincheva
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Mar Martinez-Garcia
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Carmina Montoliu
- Departamento de Patología, Facultad de Medicina, Universidad Valencia, Valencia, Spain
- Instituto de Investigación Sanitaria-INCLIVA, Valencia, Spain
| | - Marta Llansola
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
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8
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Santos RPC, Toscano ECDB, Rachid MA. Anti-inflammatory strategies for hepatic encephalopathy: preclinical studies. ARQUIVOS DE NEURO-PSIQUIATRIA 2023. [PMID: 37487550 PMCID: PMC10371400 DOI: 10.1055/s-0043-1767819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/26/2023]
Abstract
Hepatic encephalopathy (HE) is a potentially reversible neuropsychiatric syndrome. Often, HE causes cognitive and motor dysfunctions due to an acute or chronic insufficiency of the liver or a shunting between the hepatic portal vein and systemic vasculature. Liver damage induces peripheral changes, such as in the metabolism and peripheral inflammatory responses that trigger exacerbated neuroinflammation. In experimental models, anti-inflammatory strategies have demonstrated neuroprotective effects, leading to a reduction in HE-related cognitive and motor impairments. In this scenario, a growing body of evidence has shown that peripheral and central nervous system inflammation are promising preclinical targets. In this review, we performed an overview of FDA-approved drugs and natural compounds which are used in the treatment of other neurological and nonneurological diseases that have played a neuroprotective role in experimental HE, at least in part, through anti-inflammatory mechanisms. Despite the exciting results from animal models, the available data should be critically interpreted, highlighting the importance of translating the findings for clinical essays.
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Affiliation(s)
- Rafaela Pinto Coelho Santos
- Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Patologia Geral, Laboratório de Patologia Celular e Molecular, Belo Horizonte MG, Brazil
| | - Eliana Cristina de Brito Toscano
- Universidade Federal de Juiz de Fora, Faculdade de Medicina, Departamento de Patologia, Laboratório Integrado de Pesquisa em Patologia, Juiz de Fora MG, Brazil
- Universidade Federal de Juiz e Fora, Faculdade de Medicina, Programa de Pós-Graduação em Saúde, Juiz de Fora MG, Brazil
| | - Milene Alvarenga Rachid
- Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Patologia Geral, Laboratório de Patologia Celular e Molecular, Belo Horizonte MG, Brazil
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Balzano T, Llansola M, Arenas YM, Izquierdo-Altarejos P, Felipo V. Hepatic encephalopathy: investigational drugs in preclinical and early phase development. Expert Opin Investig Drugs 2023; 32:1055-1069. [PMID: 37902074 DOI: 10.1080/13543784.2023.2277386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 10/26/2023] [Indexed: 10/31/2023]
Abstract
INTRODUCTION Hepatic encephalopathy (HE) is a neuropsychiatric syndrome, in patients with liver disease, which affects life quality and span. Current treatments are lactulose or rifaximin, acting on gut microbiota. Treatments aiming ammonia levels reduction have been tested with little success. AREAS COVERED Pre-clinical research shows that the process inducing HE involves sequentially: liver failure, altered microbiome, hyperammonemia, peripheral inflammation, changes in immunophenotype and extracellular vesicles and neuroinflammation, which alters neurotransmission impairing cognitive and motor function. HE may be reversed using drugs acting at any step: modulating microbiota with probiotics or fecal transplantation; reducing peripheral inflammation with anti-TNFα, autotaxin inhibitors or silymarin; reducing neuroinflammation with sulforaphane, p38 MAP kinase or phosphodiesteras 5 inhibitors, antagonists of sphingosine-1-phosphate receptor 2, enhancing meningeal lymphatic drainage or with extracellular vesicles from mesenchymal stem cells; reducing GABAergic neurotransmission with indomethacin or golexanolone. EXPERT OPINION A factor limiting the progress of HE treatment is the lack of translation of research advances into clinical trials. Only drugs acting on microbiota or ammonia reduction have been tested in patients. It is urgent to change the mentality on how to approach HE treatment to develop clinical trials to assess drugs acting on the immune system/peripheral inflammation, neuroinflammation or neurotransmission to improve HE.
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Affiliation(s)
- Tiziano Balzano
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
- HM CINAC (Centro Integral de Neurociencias Abarca Campal), Hospital Universitario HM Puerta del Sur, HM Hospitales, Madrid, Spain
| | - Marta Llansola
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Yaiza M Arenas
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
- Departamento de Patología, Facultad de Medicina, Universidad Valencia, Valencia, Spain
| | | | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
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Liu P, Li H, Xu H, Gong J, Jiang M, Qian J, Xu Z, Shi J. Chitooligosaccharides Attenuated Hepatic Encephalopathy in Mice through Stabilizing Gut-Liver-Brain Disturbance. Mol Nutr Food Res 2023; 67:e2200158. [PMID: 36281912 DOI: 10.1002/mnfr.202200158] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 09/10/2022] [Indexed: 01/19/2023]
Abstract
SCOPE Hepatic encephalopathy (HE) refers to neurological dysfunction associated with hepatic inadequacy and gut dysbiosis. Chitooligosaccharides (COS) possesses prominent biological activities including incalculable hepatoprotective, neuroprotective and prebiotic effects. This study evaluates the protective effects of COS on HE from the influence of gut-liver-brain axis in mice. METHODS AND RESULTS Hepatic injured mice show minimal symptoms of HE, reflecting in cognitive impairment, and learning and memory retardation, while they are reversed by COS following orally administrated. Furthermore, COS ameliorates brain function through inhibiting microglial and astrocyte activation in cerebral cortex and hippocampus, promoting neuronal regeneration characterized by the increase of neuron-specific marker (neuronal nuclear antigen, NeuN). Concurrently, neuroinflammation and hepatitis are restrained by COS through descending toll-like receptors 4/Nuclear factor kappa B (TLR4/NF-κB) pathway. Additionally, the dysbiosis of the composition and structure of gut microbiota is displayed in mice with HE, while it is modified by COS through decreasing the relative abundances of Muribaculaceae, Lactobacillus, and Enterorhabdus. The enhancement of blood ammonia is crucially slipped to basal levels by COS. CONCLUSION The present study shows that COS could prevent the pathological process of HE through regulating the gut-liver-brain cross-talk, which provids new insight into fundamental roles of COS.
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Affiliation(s)
- Peng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, 214122, China
| | - Heng Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, 214122, China
| | - Hongyu Xu
- School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Jinsong Gong
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, 214122, China
| | - Min Jiang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, 214122, China
| | - Jianying Qian
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, 214122, China
| | - Zhenghong Xu
- School of Biotechnology, Jiangnan University, Wuxi, 214122, China.,National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Wuxi, 214122, China
| | - Jinsong Shi
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, 214122, China
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Hepatic Encephalopathy: Current and Emerging Treatment Modalities. Clin Gastroenterol Hepatol 2022; 20:S9-S19. [PMID: 35940731 DOI: 10.1016/j.cgh.2022.04.034] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 04/13/2022] [Accepted: 04/13/2022] [Indexed: 02/07/2023]
Abstract
Hepatic encephalopathy (HE) is a potentially reversible neurocognitive complication of cirrhosis. It has been reported in at least 30% of patients with cirrhosis and imposes a significant economic burden on caregivers and the healthcare system. Ammonia has been recognized as the culprit in HE development, and all the currently approved treatments mostly act on this toxin to help with HE resolution. After a brief overview of HE characteristics and pathophysiology, this review explores the current accepted treatments for this debilitating complication of cirrhosis. This is followed by an overview of the novel available therapies and a brief focus on future treatment modalities for HE.
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12
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Mincheva G, Gimenez-Garzo C, Izquierdo-Altarejos P, Martinez-Garcia M, Doverskog M, Blackburn TP, Hällgren A, Bäckström T, Llansola M, Felipo V. Golexanolone, a GABA A receptor modulating steroid antagonist, restores motor coordination and cognitive function in hyperammonemic rats by dual effects on peripheral inflammation and neuroinflammation. CNS Neurosci Ther 2022; 28:1861-1874. [PMID: 35880480 PMCID: PMC9532914 DOI: 10.1111/cns.13926] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 07/08/2022] [Accepted: 07/09/2022] [Indexed: 11/29/2022] Open
Abstract
Aims Hyperammonemic rats show peripheral inflammation, increased GABAergic neurotransmission and neuroinflammation in cerebellum and hippocampus which induce motor incoordination and cognitive impairment. Neuroinflammation enhances GABAergic neurotransmission in cerebellum by enhancing the TNFR1‐glutaminase‐GAT3 and TNFR1‐CCL2‐TrkB‐KCC2 pathways. Golexanolone reduces GABAA receptors potentiation by allopregnanolone. This work aimed to assess if treatment of hyperammonemic rats with golexanolone reduces peripheral inflammation and neuroinflammation and restores cognitive and motor function and to analyze underlying mechanisms. Methods Rats were treated with golexanolone and effects on peripheral inflammation, neuroinflammation, TNFR1‐glutaminase‐GAT3 and TNFR1‐CCL2‐TrkB‐KCC2 pathways, and cognitive and motor function were analyzed. Results Hyperammonemic rats show increased TNFα and reduced IL‐10 in plasma, microglia and astrocytes activation in cerebellum and hippocampus, and impaired motor coordination and spatial and short‐term memories. Treating hyperammonemic rats with golexanolone reversed changes in peripheral inflammation, microglia and astrocytes activation and restored motor coordination and spatial and short‐term memory. This was associated with reversal of the hyperammonemia‐enhanced activation in cerebellum of the TNFR1‐glutaminase‐GAT3 and TNFR1‐CCL2‐TrkB‐KCC2 pathways. Conclusion Reducing GABAA receptors activation with golexanolone reduces peripheral inflammation and neuroinflammation and improves cognitive and motor function in hyperammonemic rats. The effects identified would also occur in patients with hepatic encephalopathy and, likely, in other pathologies associated with neuroinflammation.
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Affiliation(s)
- Gergana Mincheva
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Carla Gimenez-Garzo
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | | | - Mar Martinez-Garcia
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | | | | | | | - Torbjörn Bäckström
- Umecrine Cognition AB, Solna, Sweden.,Umeå Neurosteroid Research Center, Clinical Sciences at Umeå University, Umeå, Sweden
| | - Marta Llansola
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
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Izquierdo-Altarejos P, Martínez-García M, Felipo V. Extracellular Vesicles From Hyperammonemic Rats Induce Neuroinflammation in Cerebellum of Normal Rats: Role of Increased TNFα Content. Front Immunol 2022; 13:921947. [PMID: 35911759 PMCID: PMC9325972 DOI: 10.3389/fimmu.2022.921947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Accepted: 06/13/2022] [Indexed: 12/03/2022] Open
Abstract
Hyperammonemia plays a main role in the neurological impairment in cirrhotic patients with hepatic encephalopathy. Rats with chronic hyperammonemia reproduce the motor incoordination of patients with minimal hepatic encephalopathy, which is due to enhanced GABAergic neurotransmission in cerebellum as a consequence of neuroinflammation. Extracellular vesicles (EVs) could play a key role in the transmission of peripheral alterations to the brain to induce neuroinflammation and neurological impairment in hyperammonemia and hepatic encephalopathy. EVs from plasma of hyperammonemic rats (HA-EVs) injected to normal rats induce neuroinflammation and motor incoordination, but the underlying mechanisms remain unclear. The aim of this work was to advance in the understanding of these mechanisms. To do this we used an ex vivo system. Cerebellar slices from normal rats were treated ex vivo with HA-EVs. The aims were: 1) assess if HA-EVs induce microglia and astrocytes activation and neuroinflammation in cerebellar slices of normal rats, 2) assess if this is associated with activation of the TNFR1-NF-kB-glutaminase-GAT3 pathway, 3) assess if the TNFR1-CCL2-BDNF-TrkB pathway is activated by HA-EVs and 4) assess if the increased TNFα levels in HA-EVs are responsible for the above effects and if they are prevented by blocking the action of TNFα. Our results show that ex vivo treatment of cerebellar slices from control rats with extracellular vesicles from hyperammonemic rats induce glial activation, neuroinflammation and enhance GABAergic neurotransmission, reproducing the effects induced by hyperammonemia in vivo. Moreover, we identify in detail key underlying mechanisms. HA-EVs induce the activation of both the TNFR1-CCL2-BDNF-TrkB-KCC2 pathway and the TNFR1-NF-kB-glutaminase-GAT3 pathway. Activation of these pathways enhances GABAergic neurotransmission in cerebellum, which is responsible for the induction of motor incoordination by HA-EVs. The data also show that the increased levels of TNFα in HA-EVs are responsible for the above effects and that the activation of both pathways is prevented by blocking the action of TNFα. This opens new therapeutic options to improve motor incoordination in hyperammonemia and also in cirrhotic patients with hepatic encephalopathy and likely in other pathologies in which altered cargo of extracellular vesicles contribute to the propagation of the pathology.
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Jehle A, Garaschuk O. The Interplay between cGMP and Calcium Signaling in Alzheimer’s Disease. Int J Mol Sci 2022; 23:ijms23137048. [PMID: 35806059 PMCID: PMC9266933 DOI: 10.3390/ijms23137048] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 05/31/2022] [Accepted: 06/22/2022] [Indexed: 02/04/2023] Open
Abstract
Cyclic guanosine monophosphate (cGMP) is a ubiquitous second messenger and a key molecule in many important signaling cascades in the body and brain, including phototransduction, olfaction, vasodilation, and functional hyperemia. Additionally, cGMP is involved in long-term potentiation (LTP), a cellular correlate of learning and memory, and recent studies have identified the cGMP-increasing drug Sildenafil as a potential risk modifier in Alzheimer’s disease (AD). AD development is accompanied by a net increase in the expression of nitric oxide (NO) synthases but a decreased activity of soluble guanylate cyclases, so the exact sign and extent of AD-mediated imbalance remain unclear. Moreover, human patients and mouse models of the disease present with entangled deregulation of both cGMP and Ca2+ signaling, e.g., causing changes in cGMP-mediated Ca2+ release from the intracellular stores as well as Ca2+-mediated cGMP production. Still, the mechanisms governing such interplay are poorly understood. Here, we review the recent data on mechanisms underlying the brain cGMP signaling and its interconnection with Ca2+ signaling. We also discuss the recent evidence stressing the importance of such interplay for normal brain function as well as in Alzheimer’s disease.
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15
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Rifaximin Improves Spatial Learning and Memory Impairment in Rats with Liver Damage-Associated Neuroinflammation. Biomedicines 2022; 10:biomedicines10061263. [PMID: 35740285 PMCID: PMC9219896 DOI: 10.3390/biomedicines10061263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/23/2022] [Accepted: 05/26/2022] [Indexed: 12/04/2022] Open
Abstract
Patients with non-alcoholic fatty liver disease (NAFLD) may show mild cognitive impairment. Neuroinflammation in the hippocampus mediates cognitive impairment in rat models of minimal hepatic encephalopathy (MHE). Treatment with rifaximin reverses cognitive impairment in a large proportion of cirrhotic patients with MHE. However, the underlying mechanisms remain unclear. The aims of this work were to assess if rats with mild liver damage, as a model of NAFLD, show neuroinflammation in the hippocampus and impaired cognitive function, if treatment with rifaximin reverses it, and to study the underlying mechanisms. Mild liver damage was induced with carbon-tetrachloride. Infiltration of immune cells, glial activation, and cytokine expression, as well as glutamate receptors expression in the hippocampus and cognitive function were assessed. We assessed the effects of daily treatment with rifaximin on the alterations showed by these rats. Rats with mild liver damage showed hippocampal neuroinflammation, reduced membrane expression of glutamate N-methyl-D-aspartate (NMDA) receptor subunits, and impaired spatial memory. Increased C-C Motif Chemokine Ligand 2 (CCL2), infiltration of monocytes, microglia activation, and increased tumor necrosis factor α (TNFα) were reversed by rifaximin, that normalized NMDA receptor expression and improved spatial memory. Thus, rifaximin reduces neuroinflammation and improves cognitive function in rats with mild liver damage, being a promising therapy for patients with NAFLD showing mild cognitive impairment.
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Xiong Y, Wintermark P. The Role of Sildenafil in Treating Brain Injuries in Adults and Neonates. Front Cell Neurosci 2022; 16:879649. [PMID: 35620219 PMCID: PMC9127063 DOI: 10.3389/fncel.2022.879649] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 04/04/2022] [Indexed: 12/02/2022] Open
Abstract
Sildenafil is a recognized treatment for patients suffering from erectile dysfunction and pulmonary hypertension. However, new evidence suggests that it may have a neuroprotective and a neurorestorative role in the central nervous system of both adults and neonates. Phosphodiesterase type 5-the target of sildenafil-is distributed in many cells throughout the body, including neurons and glial cells. This study is a comprehensive review of the demonstrated effects of sildenafil on the brain with respect to its function, extent of injury, neurons, neuroinflammation, myelination, and cerebral vessels.
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Affiliation(s)
- Ying Xiong
- Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, China
- Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Pia Wintermark
- Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- Division of Newborn Medicine, Department of Pediatrics, Montreal Children’s Hospital, Montreal, QC, Canada
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Hyperammonemia Enhances GABAergic Neurotransmission in Hippocampus: Underlying Mechanisms and Modulation by Extracellular cGMP. Mol Neurobiol 2022; 59:3431-3448. [PMID: 35320456 DOI: 10.1007/s12035-022-02803-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 03/16/2022] [Indexed: 10/18/2022]
Abstract
Rats with chronic hyperammonemia reproduce the cognitive and motor impairment present in patients with hepatic encephalopathy. It has been proposed that enhanced GABAergic neurotransmission in hippocampus may contribute to impaired learning and memory in hyperammonemic rats. However, there are no direct evidences of the effects of hyperammonemia on GABAergic neurotransmission in hippocampus or on the underlying mechanisms. The aims of this work were to assess if chronic hyperammonemia enhances the function of GABAA receptors in hippocampus and to identify the underlying mechanisms. Activation of GABAA receptors is enhanced in hippocampus of hyperammonemic rats, as analyzed in a multielectrode array system. Hyperammonemia reduces membrane expression of the GABA transporters GAT1 and GAT3, which is associated with increased extracellular GABA concentration. Hyperammonemia also increases gephyrin levels and phosphorylation of the β3 subunit of GABAA receptor, which are associated with increased membrane expression of the GABAA receptor subunits α1, α2, γ2, β3, and δ. Enhanced levels of extracellular GABA and increased membrane expression of GABAA receptors would be responsible for the enhanced GABAergic neurotransmission in hippocampus of hyperammonemic rats. Increasing extracellular cGMP reverses the increase in GABAA receptors activation by normalizing the membrane expression of GABA transporters and GABAA receptors. The increased GABAergic neurotransmission in hippocampus would contribute to cognitive impairment in hyperammonemic rats. The results reported suggest that reducing GABAergic tone in hippocampus by increasing extracellular cGMP or by other means may be useful to improve cognitive function in hyperammonemia and in cirrhotic patients with minimal or clinical hepatic encephalopathy.
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Akinmoladun AC, Famusiwa CD, Josiah SS, Lawal AO, Olaleye MT, Akindahunsi AA. Dihydroquercetin improves rotenone‐induced Parkinsonism by regulating NF‐κB‐mediated inflammation pathway in rats. J Biochem Mol Toxicol 2022; 36:e23022. [DOI: 10.1002/jbt.23022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 12/31/2021] [Accepted: 01/28/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Afolabi C. Akinmoladun
- Department of Biochemistry, School of Life Sciences The Federal University of Technology Akure Nigeria
| | - Courage D. Famusiwa
- Department of Biochemistry, School of Life Sciences The Federal University of Technology Akure Nigeria
| | - Sunday S. Josiah
- Department of Biochemistry, School of Life Sciences The Federal University of Technology Akure Nigeria
| | - Akeem O. Lawal
- Department of Biochemistry, School of Life Sciences The Federal University of Technology Akure Nigeria
| | - Mary T. Olaleye
- Department of Biochemistry, School of Life Sciences The Federal University of Technology Akure Nigeria
| | - Afolabi A. Akindahunsi
- Department of Biochemistry, School of Life Sciences The Federal University of Technology Akure Nigeria
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Taoro-González L, Cabrera-Pastor A, Sancho-Alonso M, Felipo V. Intracellular and extracelluar cyclic GMP in the brain and the hippocampus. VITAMINS AND HORMONES 2022; 118:247-288. [PMID: 35180929 DOI: 10.1016/bs.vh.2021.11.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Cyclic Guanosine-Monophosphate (cGMP) is implicated as second messenger in a plethora of pathways and its effects are executed mainly by cGMP-dependent protein kinases (PKG). It is involved in both peripheral (cardiovascular regulation, intestinal secretion, phototransduction, etc.) and brain (hippocampal synaptic plasticity, neuroinflammation, cognitive function, etc.) processes. Stimulation of hippocampal cGMP signaling have been proved to be beneficial in animal models of aging, Alzheimer's disease or hepatic encephalopathy, restoring different cognitive functions such as passive avoidance, object recognition or spatial memory. However, even when some inhibitors of cGMP-degrading enzymes (PDEs) are already used against peripheral pathologies, their utility as neurological treatments is still under clinical investigation. Additionally, it has been demonstrated a list of cGMP roles as not second but first messenger. The role of extracellular cGMP has been specially studied in hippocampal function and cognitive impairment in animal models and it has emerged as an important modulator of neuroinflammation-mediated cognitive alterations and hippocampal synaptic plasticity malfunction. Specifically, it has been demonstrated that extracellular cGMP decreases hippocampal IL-1β levels restoring membrane expression of glutamate receptors in the hippocampus and cognitive function in hyperammonemic rats. The mechanisms implicated are still unclear and might involve complex interactions between hippocampal neurons, astrocytes and microglia. Membrane targets for extracellular cGMP are still poorly understood and must be addressed in future studies.
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Affiliation(s)
- Lucas Taoro-González
- Department of Clinical Psychology, Psychobiology and Methodology, Area of Psycobiology, University of La Laguna, Tenerife, Spain
| | - Andrea Cabrera-Pastor
- Fundación Investigación Hospital Clínico, Instituto de Investigación Sanitaria (INCLIVA), Valencia, Spain; Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - María Sancho-Alonso
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain.
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Blaney H, DeMorrow S. Hepatic Encephalopathy: Thinking Beyond Ammonia. Clin Liver Dis (Hoboken) 2022; 19:21-24. [PMID: 35106145 PMCID: PMC8785918 DOI: 10.1002/cld.1163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Content available: Audio Recording.
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Affiliation(s)
- Hanna Blaney
- Department of Internal MedicineTexas A&M Health Science Center College of MedicineTempleTX
| | - Sharon DeMorrow
- Division of Pharmacology and ToxicologyCollege of PharmacyThe University of Texas at AustinAustinTX
- Department of Internal MedicineDell Medical SchoolThe University of Texas at AustinAustinTX
- Central Texas Veterans Health Care SystemTempleTX
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Systemic LPS-induced microglial activation results in increased GABAergic tone: A mechanism of protection against neuroinflammation in the medial prefrontal cortex in mice. Brain Behav Immun 2022; 99:53-69. [PMID: 34582995 DOI: 10.1016/j.bbi.2021.09.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 09/19/2021] [Accepted: 09/21/2021] [Indexed: 02/01/2023] Open
Abstract
Neuroinflammation with excess microglial activation and synaptic dysfunction are early symptoms of most neurological diseases. However, how microglia-associated neuroinflammation regulates synaptic activity remains obscure. We report here that acute neuroinflammation induced by intraperitoneal injection of lipopolysaccharide (LPS) results in cell-type-specific increases in inhibitory postsynaptic currents in the glutamatergic, but not the GABAergic, neurons of medial prefrontal cortex (mPFC), coinciding with excessive microglial activation. LPS causes upregulation in levels of GABAAR subunits, glutamine synthetase and vesicular GABA transporter, and downregulation in brain-derived neurotrophic factor (BDNF) and its receptor, pTrkB. Blockage of microglial activation by minocycline ameliorates LPS-induced abnormal expression of GABA signaling-related proteins and activity of synaptic and network. Moreover, minocycline prevents the mice from LPS-induced aberrant behavior, such as a reduction in total distance and time spent in the centre in the open field test; decreases in entries into the open arm of elevated-plus maze and in consumption of sucrose; increased immobility in the tail suspension test. Furthermore, upregulation of GABA signaling by tiagabine also prevents LPS-induced microglial activation and aberrant behavior. This study illustrates a mode of bidirectional constitutive signaling between the neural and immune compartments of the brain, and suggests that the mPFC is an important area for brain-immune system communication. Moreover, the present study highlights GABAergic signaling as a key therapeutic target for mitigating neuroinflammation-induced abnormal synaptic activity in the mPFC, together with the associated behavioral abnormalities.
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Claeys W, Van Hoecke L, Lefere S, Geerts A, Verhelst X, Van Vlierberghe H, Degroote H, Devisscher L, Vandenbroucke RE, Van Steenkiste C. The neurogliovascular unit in hepatic encephalopathy. JHEP Rep 2021; 3:100352. [PMID: 34611619 PMCID: PMC8476774 DOI: 10.1016/j.jhepr.2021.100352] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 07/14/2021] [Accepted: 07/23/2021] [Indexed: 12/14/2022] Open
Abstract
Hepatic encephalopathy (HE) is a neurological complication of hepatic dysfunction and portosystemic shunting. It is highly prevalent in patients with cirrhosis and is associated with poor outcomes. New insights into the role of peripheral origins in HE have led to the development of innovative treatment strategies like faecal microbiota transplantation. However, this broadening of view has not been applied fully to perturbations in the central nervous system. The old paradigm that HE is the clinical manifestation of ammonia-induced astrocyte dysfunction and its secondary neuronal consequences requires updating. In this review, we will use the holistic concept of the neurogliovascular unit to describe central nervous system disturbances in HE, an approach that has proven instrumental in other neurological disorders. We will describe HE as a global dysfunction of the neurogliovascular unit, where blood flow and nutrient supply to the brain, as well as the function of the blood-brain barrier, are impaired. This leads to an accumulation of neurotoxic substances, chief among them ammonia and inflammatory mediators, causing dysfunction of astrocytes and microglia. Finally, glymphatic dysfunction impairs the clearance of these neurotoxins, further aggravating their effect on the brain. Taking a broader view of central nervous system alterations in liver disease could serve as the basis for further research into the specific brain pathophysiology of HE, as well as the development of therapeutic strategies specifically aimed at counteracting the often irreversible central nervous system damage seen in these patients.
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Key Words
- ABC, ATP-binding cassette
- ACLF, acute-on-chronic liver failure
- AD, acute decompensation
- ALF, acute liver failure
- AOM, azoxymethane
- AQP4, aquaporin 4
- Acute Liver Failure
- Ammonia
- BBB, blood-brain barrier
- BCRP, breast cancer resistance protein
- BDL, bile duct ligation
- Blood-brain barrier
- Brain edema
- CCL, chemokine ligand
- CCR, C-C chemokine receptor
- CE, cerebral oedema
- CLD, chronic liver disease
- CLDN, claudin
- CNS, central nervous system
- CSF, cerebrospinal fluid
- Cirrhosis
- Energy metabolism
- GS, glutamine synthetase
- Glymphatic system
- HE, hepatic encephalopathy
- HO-1, heme oxygenase 1
- IL-, interleukin
- MMP-9, matrix metalloproteinase 9
- MRP, multidrug resistance associated protein
- NGVU
- NGVU, neurogliovascular unit
- NKCC1, Na-K-2Cl cotransporter 1
- Neuroinflammation
- OCLN, occludin
- ONS, oxidative and nitrosative stress
- Oxidative stress
- P-gp, P-glycoprotein
- PCA, portacaval anastomosis
- PSS, portosystemic shunt
- S1PR2, sphingosine-1-phosphate receptor 2
- SUR1, sulfonylurea receptor 1
- Systemic inflammation
- TAA, thioacetamide
- TGFβ, transforming growth factor beta
- TJ, tight junction
- TNF, tumour necrosis factor
- TNFR1, tumour necrosis factor receptor 1
- ZO, zonula occludens
- mPT, mitochondrial pore transition
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Affiliation(s)
- Wouter Claeys
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Liver Research Center Ghent, Ghent University, Ghent, Belgium
- Barriers in Inflammation, VIB Center for Inflammation Research, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Lien Van Hoecke
- Barriers in Inflammation, VIB Center for Inflammation Research, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Sander Lefere
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Liver Research Center Ghent, Ghent University, Ghent, Belgium
- Gut-Liver Immunopharmacology Unit, Department of Basic and Applied Medical Sciences; Liver Research Center Ghent; Ghent University, Ghent, Belgium
| | - Anja Geerts
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Liver Research Center Ghent, Ghent University, Ghent, Belgium
| | - Xavier Verhelst
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Liver Research Center Ghent, Ghent University, Ghent, Belgium
| | - Hans Van Vlierberghe
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Liver Research Center Ghent, Ghent University, Ghent, Belgium
| | - Helena Degroote
- Hepatology Research Unit, Department of Internal Medicine and Paediatrics, Liver Research Center Ghent, Ghent University, Ghent, Belgium
| | - Lindsey Devisscher
- Gut-Liver Immunopharmacology Unit, Department of Basic and Applied Medical Sciences; Liver Research Center Ghent; Ghent University, Ghent, Belgium
| | - Roosmarijn E. Vandenbroucke
- Barriers in Inflammation, VIB Center for Inflammation Research, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Christophe Van Steenkiste
- Antwerp University, Department of Gastroenterology and Hepatology, Antwerp, Belgium
- Department of Gastroenterology and Hepatology, Maria Middelares Hospital, Ghent, Belgium
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New Therapies of Liver Diseases: Hepatic Encephalopathy. J Clin Med 2021; 10:jcm10184050. [PMID: 34575157 PMCID: PMC8472037 DOI: 10.3390/jcm10184050] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/02/2021] [Accepted: 09/04/2021] [Indexed: 12/12/2022] Open
Abstract
Hepatic encephalopathy (HE) is a common complication of advanced liver disease which has profound implications in terms of the patients’ ability to fulfil their family and social roles, to drive and to provide for themselves. Recurrent and persistent HE is still a serious management challenge, translating into a significant burden for patients and their families, health services and society at large. The past few years have been characterized by significantly more attention towards HE and its implications; its definition has been refined and a small number of new drugs/alternative management strategies have become available, while others are underway. In this narrative review we summarize them in a pragmatic and hopefully useful fashion.
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Balzano T, Leone P, Ivaylova G, Castro MC, Reyes L, Ramón C, Malaguarnera M, Llansola M, Felipo V. Rifaximin Prevents T-Lymphocytes and Macrophages Infiltration in Cerebellum and Restores Motor Incoordination in Rats with Mild Liver Damage. Biomedicines 2021; 9:biomedicines9081002. [PMID: 34440206 PMCID: PMC8393984 DOI: 10.3390/biomedicines9081002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 08/02/2021] [Accepted: 08/03/2021] [Indexed: 12/30/2022] Open
Abstract
In patients with liver cirrhosis, minimal hepatic encephalopathy (MHE) is triggered by a shift in peripheral inflammation, promoting lymphocyte infiltration into the brain. Rifaximin improves neurological function in MHE by normalizing peripheral inflammation. Patients who died with steatohepatitis showed T-lymphocyte infiltration and neuroinflammation in the cerebellum, suggesting that MHE may already occur in these patients. The aims of this work were to assess, in a rat model of mild liver damage similar to steatohepatitis, whether: (1) the rats show impaired motor coordination in the early phases of liver damage; (2) this is associated with changes in the immune system and infiltration of immune cells into the brain; and (3) rifaximin improves motor incoordination, associated with improved peripheral inflammation, reduced infiltration of immune cells and neuroinflammation in the cerebellum, and restoration of the alterations in neurotransmission. Liver damage was induced by carbon tetrachloride (CCl4) injection over four weeks. Peripheral inflammation, immune cell infiltration, neuroinflammation, and neurotransmission in the cerebellum and motor coordination were assessed. Mild liver damage induces neuroinflammation and altered neurotransmission in the cerebellum and motor incoordination. These alterations are associated with increased TNFa, CCL20, and CX3CL1 in plasma and cerebellum, IL-17 and IL-15 in plasma, and CCL2 in cerebellum. This promotes T-lymphocyte and macrophage infiltration in the cerebellum. Early treatment with rifaximin prevents the shift in peripheral inflammation, immune cell infiltration, neuroinflammation, and motor incoordination. This report provides new clues regarding the mechanisms of the beneficial effects of rifaximin, suggesting that early rifaximin treatment could prevent neurological impairment in patients with steatohepatitis.
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The Dual Role of the GABA A Receptor in Peripheral Inflammation and Neuroinflammation: A Study in Hyperammonemic Rats. Int J Mol Sci 2021; 22:ijms22136772. [PMID: 34202516 PMCID: PMC8268725 DOI: 10.3390/ijms22136772] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/18/2021] [Accepted: 06/21/2021] [Indexed: 12/15/2022] Open
Abstract
Cognitive and motor impairment in minimal hepatic encephalopathy (MHE) are mediated by neuroinflammation, which is induced by hyperammonemia and peripheral inflammation. GABAergic neurotransmission in the cerebellum is altered in rats with chronic hyperammonemia. The mechanisms by which hyperammonemia induces neuroinflammation remain unknown. We hypothesized that GABAA receptors can modulate cerebellar neuroinflammation. The GABAA antagonist bicuculline was administrated daily (i.p.) for four weeks in control and hyperammonemic rats. Its effects on peripheral inflammation and on neuroinflammation as well as glutamate and GABA neurotransmission in the cerebellum were assessed. In hyperammonemic rats, bicuculline decreases IL-6 and TNFα and increases IL-10 in the plasma, reduces astrocyte activation, induces the microglia M2 phenotype, and reduces IL-1β and TNFα in the cerebellum. However, in control rats, bicuculline increases IL-6 and decreases IL-10 plasma levels and induces microglial activation. Bicuculline restores the membrane expression of some glutamate and GABA transporters restoring the extracellular levels of GABA in hyperammonemic rats. Blocking GABAA receptors improves peripheral inflammation and cerebellar neuroinflammation, restoring neurotransmission in hyperammonemic rats, whereas it induces inflammation and neuroinflammation in controls. This suggests a complex interaction between GABAergic and immune systems. The modulation of GABAA receptors could be a suitable target for improving neuroinflammation in MHE.
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Sandner P, Zimmer DP, Milne GT, Follmann M, Hobbs A, Stasch JP. Soluble Guanylate Cyclase Stimulators and Activators. Handb Exp Pharmacol 2021; 264:355-394. [PMID: 30689085 DOI: 10.1007/164_2018_197] [Citation(s) in RCA: 80] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
When Furchgott, Murad, and Ignarro were honored with the Nobel prize for the identification of nitric oxide (NO) in 1998, the therapeutic implications of this discovery could not be fully anticipated. This was due to the fact that available therapeutics like NO donors did not allow a constant and long-lasting cyclic guanylyl monophosphate (cGMP) stimulation and had a narrow therapeutic window. Now, 20 years later, the stimulator of soluble guanylate cyclase (sGC), riociguat, is on the market and is the only drug approved for the treatment of two forms of pulmonary hypertension (PAH/CTEPH), and a variety of other sGC stimulators and sGC activators are in preclinical and clinical development for additional indications. The discovery of sGC stimulators and sGC activators is a milestone in the field of NO/sGC/cGMP pharmacology. The sGC stimulators and sGC activators bind directly to reduced, heme-containing and oxidized, heme-free sGC, respectively, which results in an increase in cGMP production. The action of sGC stimulators at the heme-containing enzyme is independent of NO but is enhanced in the presence of NO whereas the sGC activators interact with the heme-free form of sGC. These highly innovative pharmacological principles of sGC stimulation and activation seem to have a very broad therapeutic potential. Therefore, in both academia and industry, intensive research and development efforts have been undertaken to fully exploit the therapeutic benefit of these new compound classes. Here we summarize the discovery of sGC stimulators and sGC activators and the current developments in both compound classes, including the mode of action, the chemical structures, and the genesis of the terminology and nomenclature. In addition, preclinical studies exploring multiple aspects of their in vitro, ex vivo, and in vivo pharmacology are reviewed, providing an overview of multiple potential applications. Finally, the clinical developments, investigating the treatment potential of these compounds in various diseases like heart failure, diabetic kidney disease, fibrotic diseases, and hypertension, are reported. In summary, sGC stimulators and sGC activators have a unique mode of action with a broad treatment potential in cardiovascular diseases and beyond.
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Affiliation(s)
- Peter Sandner
- Bayer AG, Pharmaceuticals R&D, Pharma Research Center, Wuppertal, Germany. .,Department of Pharmacology, Hannover Medical School, Hannover, Germany.
| | | | | | - Markus Follmann
- Bayer AG, Pharmaceuticals R&D, Pharma Research Center, Wuppertal, Germany
| | - Adrian Hobbs
- Barts and the London School of Medicine and Dentistry QMUL, London, UK
| | - Johannes-Peter Stasch
- Bayer AG, Pharmaceuticals R&D, Pharma Research Center, Wuppertal, Germany.,Institute of Pharmacy, University Halle-Wittenberg, Halle, Germany
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Regan JT, Mirczuk SM, Scudder CJ, Stacey E, Khan S, Worwood M, Powles T, Dennis-Beron JS, Ginley-Hidinger M, McGonnell IM, Volk HA, Strickland R, Tivers MS, Lawson C, Lipscomb VJ, Fowkes RC. Sensitivity of the Natriuretic Peptide/cGMP System to Hyperammonaemia in Rat C6 Glioma Cells and GPNT Brain Endothelial Cells. Cells 2021; 10:cells10020398. [PMID: 33672024 PMCID: PMC7919485 DOI: 10.3390/cells10020398] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 02/05/2021] [Accepted: 02/11/2021] [Indexed: 12/16/2022] Open
Abstract
C-type natriuretic peptide (CNP) is the major natriuretic peptide of the central nervous system and acts via its selective guanylyl cyclase-B (GC-B) receptor to regulate cGMP production in neurons, astrocytes and endothelial cells. CNP is implicated in the regulation of neurogenesis, axonal bifurcation, as well as learning and memory. Several neurological disorders result in toxic concentrations of ammonia (hyperammonaemia), which can adversely affect astrocyte function. However, the relationship between CNP and hyperammonaemia is poorly understood. Here, we examine the molecular and pharmacological control of CNP in rat C6 glioma cells and rat GPNT brain endothelial cells, under conditions of hyperammonaemia. Concentration-dependent inhibition of C6 glioma cell proliferation by hyperammonaemia was unaffected by CNP co-treatment. Furthermore, hyperammonaemia pre-treatment (for 1 h and 24 h) caused a significant inhibition in subsequent CNP-stimulated cGMP accumulation in both C6 and GPNT cells, whereas nitric-oxide-dependent cGMP accumulation was not affected. CNP-stimulated cGMP efflux from C6 glioma cells was significantly reduced under conditions of hyperammonaemia, potentially via a mechanism involving changed in phosphodiesterase expression. Hyperammonaemia-stimulated ROS production was unaffected by CNP but enhanced by a nitric oxide donor in C6 cells. Extracellular vesicle production from C6 cells was enhanced by hyperammonaemia, and these vesicles caused impaired CNP-stimulated cGMP signalling in GPNT cells. Collectively, these data demonstrate functional interaction between CNP signalling and hyperammonaemia in C6 glioma and GPNT cells, but the exact mechanisms remain to be established.
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Affiliation(s)
- Jacob T. Regan
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - Samantha M. Mirczuk
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (I.M.M.); (C.L.)
| | - Christopher J. Scudder
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (I.M.M.); (C.L.)
| | - Emily Stacey
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - Sabah Khan
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - Michael Worwood
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - Torinn Powles
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - J. Sebastian Dennis-Beron
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - Matthew Ginley-Hidinger
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
| | - Imelda M. McGonnell
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (I.M.M.); (C.L.)
| | - Holger A. Volk
- Stiftung Tierärztliche Hochschule Hannover, Klinik für Kleintiere, Bünteweg, 930559 Hannover, Germany;
| | - Rhiannon Strickland
- Clinical Sciences & Services, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK; (R.S.); (V.J.L.)
| | - Michael S. Tivers
- Paragon Veterinary Referrals, Paragon Business Village Paragon Way, Red Hall Cres, Wakefield WF1 2DF, UK;
| | - Charlotte Lawson
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (I.M.M.); (C.L.)
| | - Victoria J. Lipscomb
- Clinical Sciences & Services, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK; (R.S.); (V.J.L.)
| | - Robert C. Fowkes
- Endocrine Signalling Group, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (J.T.R.); (S.M.M.); (C.J.S.); (E.S.); (S.K.); (M.W.); (T.P.); (J.S.D.-B.); (M.G.-H.)
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK; (I.M.M.); (C.L.)
- Correspondence: ; Tel.: +44-207-468-1215
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Arenas YM, Cabrera-Pastor A, Juciute N, Mora-Navarro E, Felipo V. Blocking glycine receptors reduces neuroinflammation and restores neurotransmission in cerebellum through ADAM17-TNFR1-NF-κβ pathway. J Neuroinflammation 2020; 17:269. [PMID: 32917219 PMCID: PMC7488331 DOI: 10.1186/s12974-020-01941-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 08/24/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Chronic hyperammonemia induces neuroinflammation in cerebellum, with glial activation and enhanced activation of the TNFR1-NF-kB-glutaminase-glutamate-GABA pathway. Hyperammonemia also increases glycinergic neurotransmission. These alterations contribute to cognitive and motor impairment. Activation of glycine receptors is reduced by extracellular cGMP, which levels are reduced in cerebellum of hyperammonemic rats in vivo. We hypothesized that enhanced glycinergic neurotransmission in hyperammonemic rats (1) contributes to induce neuroinflammation and glutamatergic and GABAergic neurotransmission alterations; (2) is a consequence of the reduced extracellular cGMP levels. The aims were to assess, in cerebellum of hyperammonemic rats, (a) whether blocking glycine receptors with the antagonist strychnine reduces neuroinflammation; (b) the cellular localization of glycine receptor; (c) the effects of blocking glycine receptors on the TNFR1-NF-kB-glutaminase-glutamate-GABA pathway and microglia activation; (d) whether adding extracellular cGMP reproduces the effects of strychnine. METHODS We analyzed in freshly isolated cerebellar slices from control or hyperammonemic rats the effects of strychnine on activation of microglia and astrocytes, the content of TNFa and IL1b, the surface expression of ADAM17, TNFR1 and transporters, the phosphorylation levels of ERK, p38 and ADAM17. The cellular localization of glycine receptor was assessed by immunofluorescence. We analyzed the content of TNFa, IL1b, HMGB1, glutaminase, and the level of TNF-a mRNA and NF-κB in Purkinje neurons. Extracellular concentrations of glutamate and GABA were performed by in vivo microdialysis in cerebellum. We tested whether extracellular cGMP reproduces the effects of strychnine in ex vivo cerebellar slices. RESULTS Glycine receptors are expressed mainly in Purkinje cells. In hyperammonemic rats, enhanced glycinergic neurotransmission leads to reduced membrane expression of ADAM17, resulting in increased surface expression and activation of TNFR1 and of the associated NF-kB pathway. This increases the expression in Purkinje neurons of TNFa, IL-1b, HMGB1, and glutaminase. Increased glutaminase activity leads to increased extracellular glutamate, which increases extracellular GABA. Increased extracellular glutamate and HMGB1 potentiate microglial activation. Blocking glycine receptors with strychnine or extracellular cGMP completely prevents the above pathway in hyperammonemic rats. CONCLUSIONS Glycinergic neurotransmission modulates neuroinflammation. Enhanced glycinergic neurotransmission in hyperammonemia would be due to reduced extracellular cGMP. These results shed some light on possible new therapeutic target pathways for pathologies associated to neuroinflammation.
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Affiliation(s)
- Yaiza M Arenas
- Laboratory of Neurobiology, Príncipe Felipe Research Center Valencia, C/Eduardo Primo Yúfera 3, 46012, Valencia, Spain
| | - Andrea Cabrera-Pastor
- Laboratory of Neurobiology, Príncipe Felipe Research Center Valencia, C/Eduardo Primo Yúfera 3, 46012, Valencia, Spain.
- Laboratory of Neurological Impairment, Health Research Institute INCLIVA, 46010, Valencia, Spain.
| | - Nora Juciute
- Laboratory of Neurobiology, Príncipe Felipe Research Center Valencia, C/Eduardo Primo Yúfera 3, 46012, Valencia, Spain
| | - Eloy Mora-Navarro
- Laboratory of Neurobiology, Príncipe Felipe Research Center Valencia, C/Eduardo Primo Yúfera 3, 46012, Valencia, Spain
| | - Vicente Felipo
- Laboratory of Neurobiology, Príncipe Felipe Research Center Valencia, C/Eduardo Primo Yúfera 3, 46012, Valencia, Spain
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Ribaudo G, Ongaro A, Zagotto G, Memo M, Gianoncelli A. Therapeutic Potential of Phosphodiesterase Inhibitors against Neurodegeneration: The Perspective of the Medicinal Chemist. ACS Chem Neurosci 2020; 11:1726-1739. [PMID: 32401481 PMCID: PMC8007108 DOI: 10.1021/acschemneuro.0c00244] [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] [Indexed: 12/14/2022] Open
Abstract
![]()
Increasing human
life expectancy prompts the development of novel
remedies for cognitive decline: 44 million people worldwide are affected
by dementia, and this number is predicted to triple by 2050. Acetylcholinesterase
and N-methyl-d-aspartate receptors represent
the targets of currently available drugs for Alzheimer’s disease,
which are characterized by limited efficacy. Thus, the search for
therapeutic agents with alternative or combined mechanisms of action
is wide open. Since variations in 3′,5′-cyclic adenosine
monophosphate, 3′,5′-cyclic guanosine monophosphate,
and/or nitric oxide levels interfere with downstream pathways involved
in memory processes, evidence supporting the potential of phosphodiesterase
(PDE) inhibitors in contrasting neurodegeneration should be
critically considered. For the preparation of this Review, more than
140 scientific papers were retrieved by searching PubMed and Scopus
databases. A systematic approach was adopted when overviewing the
different PDE isoforms, taking into account details on brain localization,
downstream molecular mechanisms, and inhibitors currently under study,
according to available in vitro and in vivo data. In the context of drug repurposing, a section focusing on
PDE5 was introduced. Original computational studies were performed
to rationalize the emerging evidence that suggests the role of PDE5
inhibitors as multi-target agents against neurodegeneration.
Moreover, since such compounds must cross the blood–brain barrier
and reach inhibitory concentrations in the central nervous system
to exert their therapeutic activity, physicochemical parameters
were analyzed and discussed. Taken together, literature and computational
data suggest that some PDE5 inhibitors, such as tadalafil, represent
promising candidates.
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Affiliation(s)
- Giovanni Ribaudo
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
| | - Alberto Ongaro
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
| | - Giuseppe Zagotto
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Via Marzolo 5, 35131 Padova, Italy
| | - Maurizio Memo
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
| | - Alessandra Gianoncelli
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
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30
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Kerbert AJC, Jalan R. Recent advances in understanding and managing hepatic encephalopathy in chronic liver disease. F1000Res 2020; 9. [PMID: 32399191 PMCID: PMC7194462 DOI: 10.12688/f1000research.22183.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/21/2020] [Indexed: 12/12/2022] Open
Abstract
Hepatic encephalopathy (HE) is a common, severe complication of advanced chronic liver disease (CLD) and has a devastating impact on the patient’s quality of life and prognosis. The neurotoxin ammonia and the presence of systemic and neurological inflammation are considered the key drivers of this neuropsychiatric syndrome. Treatment options available in routine clinical practice are limited, and the development of novel therapies is hampered owing to the complexity and heterogeneity of HE. This review article aims to outline the current understanding of the pathomechanisms of HE and the recent advances in the identification and development of novel therapeutic targets.
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Affiliation(s)
- Annarein J C Kerbert
- Institute for Liver and Digestive Health, University College London, Royal Free Campus, Rowland Hill Street, London, NW3 2PF, UK
| | - Rajiv Jalan
- Institute for Liver and Digestive Health, University College London, Royal Free Campus, Rowland Hill Street, London, NW3 2PF, UK
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31
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Duarte-Silva E, Filho AJMC, Barichello T, Quevedo J, Macedo D, Peixoto C. Phosphodiesterase-5 inhibitors: Shedding new light on the darkness of depression? J Affect Disord 2020; 264:138-149. [PMID: 32056743 DOI: 10.1016/j.jad.2019.11.114] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 11/22/2019] [Accepted: 11/26/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND Phosphodiesterase-5 inhibitors (PDE5Is) are used to treat erectile dysfunction (ED). Recently, the antidepressant-like effect of PDE5Is was demonstrated in animal models of depression. In clinical settings, PDE5Is were studied only for ED associated depression. Hence, there are no studies evaluating the effects of PDE5Is for the treatment of major depressive disorder (MDD) without ED. In this review article, we aimed to discuss the use of PDE5Is in the context of MDD, highlighting the roles of PDE genes in the development of MDD, the potential mechanisms by which PDE5Is can be beneficial for MDD and the potentials and limitations of PDE5Is repurposing to treat MDD. METHODS We used PubMed (MEDLINE) database to collect the studies cited in this review. Papers written in English language regardless the year of publication were selected. RESULTS A few preclinical studies support the antidepressant-like activity of PDE5Is. Clinical studies in men with ED and depression suggest that PDE5Is improve depressive symptoms. No clinical studies were conducted in subjects suffering from depression without ED. Antidepressant effect of PDE5Is may be explained by multiple mechanisms including inhibition of brain inflammation and modulation of neuroplasticity. LIMITATIONS The low number of preclinical and absence of clinical studies to support the antidepressant effect of PDE5Is. CONCLUSIONS No clinical trial was conducted to date evaluating PDE5Is in depressed patients without ED. PDE5Is' anti-inflammatory and neuroplasticity mechanisms may justify the potential antidepressant effect of these drugs. Despite this, clinical trials evaluating their efficacy in depressed patients need to be conducted.
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Affiliation(s)
- Eduardo Duarte-Silva
- Laboratory of Ultrastructure, Aggeu Magalhães Institute (IAM), Oswaldo Cruz Foundation (FIOCRUZ-PE), Recife, PE, Brazil; Graduate Program in Biosciences and Biotechnology for Health (PPGBBS), Aggeu Magalhães Institute (IAM), Recife, PE, Brazil.
| | - Adriano José Maia Chaves Filho
- Neuropsychopharmacology Laboratory, Drug Research and Development Center, Faculty of Medicine, Universidade Federal do Ceará, Fortaleza, CE, Brazil
| | - Tatiana Barichello
- Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, 1941 East Road, Houston, TX 77054, United States; Laboratory of Neurosciences, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina-UNESC, Criciúma, SC, Brazil; Center of Excellence on Mood Disorders, Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States.
| | - João Quevedo
- Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, 1941 East Road, Houston, TX 77054, United States; Laboratory of Neurosciences, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina-UNESC, Criciúma, SC, Brazil; Center of Excellence on Mood Disorders, Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States.
| | - Danielle Macedo
- Neuropsychopharmacology Laboratory, Drug Research and Development Center, Faculty of Medicine, Universidade Federal do Ceará, Fortaleza, CE, Brazil; Department of Physiology and Pharmacology, Faculty of Medicine, Universidade Federal do Ceará, Fortaleza, CE, Brazil; National Institute for Translational Medicine (INCT-TM, CNPq), Ribeirão Preto, Brazil
| | - Christina Peixoto
- Laboratory of Ultrastructure, Aggeu Magalhães Institute (IAM), Oswaldo Cruz Foundation (FIOCRUZ-PE), Recife, PE, Brazil; National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
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Jaeger V, DeMorrow S, McMillin M. The Direct Contribution of Astrocytes and Microglia to the Pathogenesis of Hepatic Encephalopathy. J Clin Transl Hepatol 2019; 7:352-361. [PMID: 31915605 PMCID: PMC6943208 DOI: 10.14218/jcth.2019.00025] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 10/07/2019] [Accepted: 10/24/2019] [Indexed: 02/06/2023] Open
Abstract
Hepatic encephalopathy is a neurological complication resulting from loss of hepatic function and is associated with poor clinical outcomes. During acute liver failure over 20% of mortality can be associated with the development of hepatic encephalopathy. In patients with liver cirrhosis, 1-year survival for those that develop overt hepatic encephalopathy is under 50%. The pathogenesis of hepatic encephalopathy is complicated due to the multiple disruptions in homeostasis that occur following a reduction in liver function. Of these, elevations of ammonia and neuroinflammation have been shown to play a significant contributing role to the development of hepatic encephalopathy. Disruption of the urea cycle following liver dysfunction leads to elevations of circulating ammonia, which enter the brain and disrupt the functioning of astrocytes. This results in dysregulation of metabolic pathways in astrocytes, oxidative stress and cerebral edema. Besides ammonia, circulating chemokines and cytokines are increased following liver injury, leading to activation of microglia and a subsequent neuroinflammatory response. The combination of astrocyte dysfunction and microglia activation are significant contributing factors to the pathogenesis of hepatic encephalopathy.
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Affiliation(s)
- Victoria Jaeger
- Baylor Scott & White Health, Department of Internal Medicine, Temple, TX, USA
| | - Sharon DeMorrow
- Texas A&M University Health Science Center, Department of Medical Physiology, Temple, TX, USA
- Central Texas Veterans Health Care System, Temple, TX, USA
- University of Texas at Austin, Dell Medical School, Department of Internal Medicine, Austin, TX, USA
- University of Texas at Austin, College of Pharmacy, Austin, TX, USA
| | - Matthew McMillin
- Texas A&M University Health Science Center, Department of Medical Physiology, Temple, TX, USA
- Central Texas Veterans Health Care System, Temple, TX, USA
- University of Texas at Austin, Dell Medical School, Department of Internal Medicine, Austin, TX, USA
- Correspondence to: Matthew McMillin, University of Texas at Austin Dell Medical School, 1601 Trinity Street, Building B, Austin, TX 78701, USA. Tel: +1-512-495-5037, Fax: +1-512-495-5839, E-mail:
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33
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cGMP signaling pathway in hepatic encephalopathy neuroinflammation and cognition. Int Immunopharmacol 2019; 79:106082. [PMID: 31869775 DOI: 10.1016/j.intimp.2019.106082] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 11/05/2019] [Accepted: 11/24/2019] [Indexed: 12/25/2022]
Abstract
Hepatic encephalopathy (HE) is a complex neuropsychiatric syndrome that results from liver failure and is characterized by a wide range of symptoms such as alteration in the sleep-waking cycle, neuromuscular coordination, mood, and cognition. The deregulation of nitric oxide (NO)/cyclic guanosine monophosphate (cGMP)/protein kinase G (PKG) signaling pathway is thought to play an important role in the etiology and progression of neurodegenerative diseases, and several studies pointed that the cGMP signaling is impaired in patients with HE and experimental models of chronic hyperammonemia. This review aimed to briefly present the current knowledge of the cGMP signaling pathways in neuroinflammation, neurogenesis, and memory in hepatic encephalopathy and its potential therapeutic role.
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34
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Schepers M, Tiane A, Paes D, Sanchez S, Rombaut B, Piccart E, Rutten BPF, Brône B, Hellings N, Prickaerts J, Vanmierlo T. Targeting Phosphodiesterases-Towards a Tailor-Made Approach in Multiple Sclerosis Treatment. Front Immunol 2019; 10:1727. [PMID: 31396231 PMCID: PMC6667646 DOI: 10.3389/fimmu.2019.01727] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 07/09/2019] [Indexed: 12/11/2022] Open
Abstract
Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system (CNS) characterized by heterogeneous clinical symptoms including gradual muscle weakness, fatigue, and cognitive impairment. The disease course of MS can be classified into a relapsing-remitting (RR) phase defined by periods of neurological disabilities, and a progressive phase where neurological decline is persistent. Pathologically, MS is defined by a destructive immunological and neuro-degenerative interplay. Current treatments largely target the inflammatory processes and slow disease progression at best. Therefore, there is an urgent need to develop next-generation therapeutic strategies that target both neuroinflammatory and degenerative processes. It has been shown that elevating second messengers (cAMP and cGMP) is important for controlling inflammatory damage and inducing CNS repair. Phosphodiesterases (PDEs) have been studied extensively in a wide range of disorders as they breakdown these second messengers, rendering them crucial regulators. In this review, we provide an overview of the role of PDE inhibition in limiting pathological inflammation and stimulating regenerative processes in MS.
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Affiliation(s)
- Melissa Schepers
- Department of Neuroimmunology, European Graduate School of Neuroscience, Biomedical Research Institute, Hasselt University, Hasselt, Belgium.,Department Psychiatry and Neuropsychology, European Graduate School of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Assia Tiane
- Department of Neuroimmunology, European Graduate School of Neuroscience, Biomedical Research Institute, Hasselt University, Hasselt, Belgium.,Department Psychiatry and Neuropsychology, European Graduate School of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Dean Paes
- Department of Neuroimmunology, European Graduate School of Neuroscience, Biomedical Research Institute, Hasselt University, Hasselt, Belgium.,Department Psychiatry and Neuropsychology, European Graduate School of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Selien Sanchez
- Department of Morphology, Biomedical Research Institute, Hasselt University, Hasselt, Belgium
| | - Ben Rombaut
- Department of Physiology, Biomedical Research Institute, Hasselt University, Hasselt, Belgium
| | - Elisabeth Piccart
- Department of Neuroimmunology, European Graduate School of Neuroscience, Biomedical Research Institute, Hasselt University, Hasselt, Belgium.,Department Psychiatry and Neuropsychology, European Graduate School of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Bart P F Rutten
- Department Psychiatry and Neuropsychology, European Graduate School of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Bert Brône
- Department of Physiology, Biomedical Research Institute, Hasselt University, Hasselt, Belgium
| | - Niels Hellings
- Department of Neuroimmunology, European Graduate School of Neuroscience, Biomedical Research Institute, Hasselt University, Hasselt, Belgium
| | - Jos Prickaerts
- Department Psychiatry and Neuropsychology, European Graduate School of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Tim Vanmierlo
- Department of Neuroimmunology, European Graduate School of Neuroscience, Biomedical Research Institute, Hasselt University, Hasselt, Belgium.,Department Psychiatry and Neuropsychology, European Graduate School of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands
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Cabrera‐Pastor A, Llansola M, Montoliu C, Malaguarnera M, Balzano T, Taoro‐Gonzalez L, García‐García R, Mangas‐Losada A, Izquierdo‐Altarejos P, Arenas YM, Leone P, Felipo V. Peripheral inflammation induces neuroinflammation that alters neurotransmission and cognitive and motor function in hepatic encephalopathy: Underlying mechanisms and therapeutic implications. Acta Physiol (Oxf) 2019; 226:e13270. [PMID: 30830722 DOI: 10.1111/apha.13270] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 03/01/2019] [Accepted: 03/01/2019] [Indexed: 12/11/2022]
Abstract
Several million patients with liver cirrhosis suffer minimal hepatic encephalopathy (MHE), with mild cognitive and coordination impairments that reduce their quality of life and life span. Hyperammonaemia and peripheral inflammation act synergistically to induce these neurological alterations. We propose that MHE appearance is because of the changes in peripheral immune system, which are transmitted to brain, leading to neuroinflammation that alters neurotransmission leading to cognitive and motor alterations. We summarize studies showing that MHE in cirrhotic patients is associated with alterations in the immune system and that patients died with HE show neuroinflammation in cerebellum, with microglial and astrocytic activation and Purkinje cell loss. We also summarize studies in animal models of MHE on the role of peripheral inflammation in neuroinflammation induction, how neuroinflammation alters neurotransmission and how this leads to cognitive and motor alterations. These studies identify therapeutic targets and treatments that improve cognitive and motor function. Rats with MHE show neuroinflammation in hippocampus and altered NMDA and AMPA receptor membrane expression, which impairs spatial learning and memory. Neuroinflammation in cerebellum is associated with altered GABA transporters and extracellular GABA, which impair motor coordination and learning in a Y maze. These alterations are reversed by treatments that reduce peripheral inflammation (anti-TNFα, ibuprofen), neuroinflammation (sulphoraphane, p38 inhibitors), GABAergic tone (bicuculline, pregnenolone sulphate) or increase extracellular cGMP (sildenafil or cGMP). The mechanisms identified would also occur in other chronic diseases associated with inflammation, aging and some mental and neurodegenerative diseases. Treatments that improve MHE may also be beneficial to treat these pathologies.
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Affiliation(s)
- Andrea Cabrera‐Pastor
- Laboratory of Neurobiology Centro de Investigación Principe Felipe Valencia Spain
- Fundacion Investigacion Hospital Clinico Valencia, INCLIVA Valencia Spain
| | - Marta Llansola
- Laboratory of Neurobiology Centro de Investigación Principe Felipe Valencia Spain
| | - Carmina Montoliu
- Fundacion Investigacion Hospital Clinico Valencia, INCLIVA Valencia Spain
| | - Michele Malaguarnera
- Laboratory of Neurobiology Centro de Investigación Principe Felipe Valencia Spain
| | - Tiziano Balzano
- Laboratory of Neurobiology Centro de Investigación Principe Felipe Valencia Spain
| | - Lucas Taoro‐Gonzalez
- Laboratory of Neurobiology Centro de Investigación Principe Felipe Valencia Spain
| | - Raquel García‐García
- Laboratory of Neurobiology Centro de Investigación Principe Felipe Valencia Spain
| | - Alba Mangas‐Losada
- Fundacion Investigacion Hospital Clinico Valencia, INCLIVA Valencia Spain
| | | | - Yaiza M. Arenas
- Laboratory of Neurobiology Centro de Investigación Principe Felipe Valencia Spain
| | - Paola Leone
- Laboratory of Neurobiology Centro de Investigación Principe Felipe Valencia Spain
| | - Vicente Felipo
- Laboratory of Neurobiology Centro de Investigación Principe Felipe Valencia Spain
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Lima LCD, Miranda AS, Ferreira RN, Rachid MA, Simões e Silva AC. Hepatic encephalopathy: Lessons from preclinical studies. World J Hepatol 2019; 11:173-185. [PMID: 30820267 PMCID: PMC6393717 DOI: 10.4254/wjh.v11.i2.173] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 11/19/2018] [Accepted: 01/28/2019] [Indexed: 02/06/2023] Open
Abstract
Hepatic encephalopathy (HE) is a major complication that is closely related to the progression of end-stage liver disease. Metabolic changes in advanced liver failure can promote cognition impairment, attention deficits and motor dysfunction that may result in coma and death. HE can be subdivided according to the type of hepatic injury, namely, type A, which results from acute liver failure, type B, which is associated with a portosystemic shunting without intrinsic liver disease, and type C, which is due to chronic liver disease. Several studies have investigated the pathogenesis of the disease, and most of the mechanisms have been explored using animal models. This article aimed to review the use of preclinical models to investigate HE. The most used animal species are rats and mice. Experimental models of type A HE include surgical procedures and the administration of hepatotoxic medications, whereas models of types B and C HE are generally surgically induced lesions in liver tissue, which evolve to hepatic cirrhosis. Preclinical models have allowed the comprehension of the pathways related to HE.
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Affiliation(s)
- Luiza Cioglia Dias Lima
- Departamento de Patologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Minas Gerais 31270-901, Brasil
| | - Aline Silva Miranda
- Departamento de Morfologia, Instituto de Ciências Biológicas, UFMG, Belo Horizonte, Minas Gerais 30130-100, Brasil
- Laboratório Interdisciplinar de Investigação Médica, Faculdade de Medicina, UFMG, Belo Horizonte, Minas Gerais 30130-100, Brasil
| | - Rodrigo Novaes Ferreira
- Departamento de Morfologia, Instituto de Ciências Biológicas, UFMG, Belo Horizonte, Minas Gerais 30130-100, Brasil
| | - Milene Alvarenga Rachid
- Departamento de Patologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Minas Gerais 31270-901, Brasil
| | - Ana Cristina Simões e Silva
- Laboratório Interdisciplinar de Investigação Médica, Faculdade de Medicina, UFMG, Belo Horizonte, Minas Gerais 30130-100, Brasil
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Malaguarnera M, Llansola M, Balzano T, Gómez-Giménez B, Antúnez-Muñoz C, Martínez-Alarcón N, Mahdinia R, Felipo V. Bicuculline Reduces Neuroinflammation in Hippocampus and Improves Spatial Learning and Anxiety in Hyperammonemic Rats. Role of Glutamate Receptors. Front Pharmacol 2019; 10:132. [PMID: 30858801 PMCID: PMC6397886 DOI: 10.3389/fphar.2019.00132] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Accepted: 02/05/2019] [Indexed: 01/29/2023] Open
Abstract
Patients with liver cirrhosis may develop minimal hepatic encephalopathy (MHE) with mild cognitive impairment. Hyperammonemia is a main contributor to cognitive impairment in MHE, which is mediated by neuroinflammation. GABAergic neurotransmission is altered in hyperammonemic rats. We hypothesized that, in hyperammonemic rats, (a) enhanced GABAergic tone would contribute to induce neuroinflammation, which would be improved by reducing GABAergic tone by chronic bicuculline treatment; (b) this would improve spatial learning and memory impairment; and (c) modulation of glutamatergic neurotransmission would mediate this cognitive improvement. The aim of this work was to assess the above hypotheses. Bicuculline was administrated intraperitoneally once a day for 4 weeks to control and hyperammonemic rats. The effects of bicuculline on microglia and astrocyte activation, IL-1β content, on membrane expression of AMPA and NMDA glutamate receptors subunits in the hippocampus and on spatial learning and memory as well as anxiety were assessed. Treatment with bicuculline reduces astrocyte activation and IL-1β but not microglia activation in the hippocampus of hyperammonemic rats. Bicuculline reverses the changes in membrane expression of AMPA receptor subunits GluA1 and GluA2 and of the NR2B (but not NR1 and NR2A) subunit of NMDA receptors. Bicuculline improves spatial learning and working memory and decreases anxiety in hyperammonemic rats. In hyperammonemia, enhanced activation of GABAA receptors in the hippocampus contributes to some but not all aspects of neuroinflammation, to altered glutamatergic neurotransmission and to impairment of spatial learning and memory as well as anxiety, all of which are reversed by reducing activation of GABAA receptors with bicuculline.
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Affiliation(s)
- Michele Malaguarnera
- Laboratory of Neurobiology, Centro Investigación Príncipe Felipe de Valencia, Valencia, Spain
| | - Marta Llansola
- Laboratory of Neurobiology, Centro Investigación Príncipe Felipe de Valencia, Valencia, Spain
| | - Tiziano Balzano
- Laboratory of Neurobiology, Centro Investigación Príncipe Felipe de Valencia, Valencia, Spain
| | - Belén Gómez-Giménez
- Laboratory of Neurobiology, Centro Investigación Príncipe Felipe de Valencia, Valencia, Spain
| | - Carles Antúnez-Muñoz
- Laboratory of Neurobiology, Centro Investigación Príncipe Felipe de Valencia, Valencia, Spain
| | - Núria Martínez-Alarcón
- Laboratory of Neurobiology, Centro Investigación Príncipe Felipe de Valencia, Valencia, Spain
| | - Rahebeh Mahdinia
- Laboratory of Neurobiology, Centro Investigación Príncipe Felipe de Valencia, Valencia, Spain
- Faculty of Biology, Damghan University, Damghan, Iran
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro Investigación Príncipe Felipe de Valencia, Valencia, Spain
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Hepatic encephalopathy 2018: A clinical practice guideline by the Italian Association for the Study of the Liver (AISF). Dig Liver Dis 2019; 51:190-205. [PMID: 30606696 DOI: 10.1016/j.dld.2018.11.035] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 11/27/2018] [Accepted: 11/28/2018] [Indexed: 12/11/2022]
Abstract
Hepatic encephalopathy (HE) is a common, worrisome and sometimes difficult to manage complication of end-stage liver disease. HE is often recurrent, requiring multiple hospital admissions. It can have serious implications in terms of a patient's ability to perform complex tasks (for example driving), their earning capacity, their social and family roles. This guideline reviews current knowledge on HE definition, pathophysiology, diagnosis and treatment, both by general principles and by way of a summary of available drugs and treatment strategies. The quality of the published, pertinent evidence is graded, and practical recommendations are made. Where possible, these are placed within the Italian health service context, with reference to local diagnosis and management experience.
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Extracellular cGMP Reverses Altered Membrane Expression of AMPA Receptors in Hippocampus of Hyperammonemic Rats: Underlying Mechanisms. Mol Neurobiol 2018; 56:4428-4439. [PMID: 30328550 DOI: 10.1007/s12035-018-1387-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 10/09/2018] [Indexed: 01/06/2023]
Abstract
Chronic hyperammonemia impairs spatial memory by altering membrane expression of GluA1 and GluA2 subunits of AMPA receptors in hippocampus. Intracerebral administration of extracellular cGMP to hyperammonemic rats restores spatial memory and membrane expression of AMPA receptors. The underlying molecular mechanisms remain unknown and cannot be analyzed in vivo. The aims of the present work were to (1) assess whether extracellular cGMP reverses the alterations in membrane expression of GluA1 and GluA2 in hippocampus of hyperammonemic rats ex vivo and (2) identify the underlying mechanisms. To reach these aims, we used freshly isolated hippocampal slices from control and hyperammonemic rats and treated them ex vivo with extracellular cGMP. Extracellular cGMP normalizes membrane expression of GluA2 restoring its phosphorylation in Ser880 because it restores PKCζ activation by Thr560 auto-phosphorylation, which is a consequence of normalization by extracellular cGMP of phosphorylation and activity of p38 which was increased in hyperammonemic rats. Normalization of p38 is a consequence of normalization of membrane expression of the GluN2B subunit of NMDA receptor, mediated by a reduction in its phosphorylation in Tyr1472 due to reduction of Src activation, which was over-activated in hyperammonemic rats. Extracellular cGMP also restores membrane expression of GluA1 increasing its phosphorylation at Ser831 because it restores CaMKII membrane association and phosphorylation in Thr286. All these effects of extracellular cGMP are due to a reduction of hippocampal IL-1β levels in hyperammonemic rats, which reduces IL-1 receptor-mediated Src over-activation. Reduction in IL-1β levels is due to the reduction of microglia activation in hippocampus of hyperammonemic rats.
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Ochoa-Sanchez R, Rose CF. Pathogenesis of Hepatic Encephalopathy in Chronic Liver Disease. J Clin Exp Hepatol 2018; 8:262-271. [PMID: 30302043 PMCID: PMC6175755 DOI: 10.1016/j.jceh.2018.08.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 08/09/2018] [Indexed: 12/12/2022] Open
Abstract
Hepatic encephalopathy (HE) is a complex neuropsychiatric syndrome that occurs during chronic liver disease (CLD). While ammonia and other precipitating factors in liver disease including inflammation, bile acids, oxidative stress, and lactate play a role in the pathogenesis of HE, the exact mechanism that leads to HE is not fully understood. Notably, accumulating evidence points toward a synergic effect rather than independent actions among precipitating factors that contributes to the development and severity of HE in CLD. Hence, this review is aimed to briefly discuss the single and synergic interplay of pathological factors in the progression and severity of HE.
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Key Words
- AQP4, Aquaporin 4
- BAs, Bile Acids
- BBB, Blood-Brain Barrier
- BDL, Bile Duct Ligation
- CLD, Chronic Liver Disease
- CSF, Cerebrospinal Fluid
- GABA, Gamma-Aminobutyric Acid
- GAMSAs, GABAA Receptor Modulating Steroid Antagonists
- GFAP, Glial Fibrillary Acid Protein
- GLAST, Glial Glutamate-Aspartate Transporter
- GPR81, G-Protein-Coupled Receptor 81
- GS, Glutamine Synthetase
- HE, Hepatic Encephalopathy
- ICP, Intracranial Pressure
- ILs, Interleukins
- MRI, Magnetic Resonance Imaging
- NF-?B, Nuclear Factor Kappa B
- NMDA, N-Methyl-d-Aspartate Glutamate Receptor
- NO, Nitric Oxide
- PCA, Portacaval Anastomosis
- ROS, Reactive Oxygen Species
- TJ, Tight Junction
- TNF-a, Tumor Necrosis Alpha
- ammonia
- astrocyte swelling
- bile acids
- brain edema
- cGMP, Cyclic Guanosine Monophosphate
- cirrhosis
- hepatic encephalopathy
- inflammation
- lactate
- mGluR, Metabotropic Glutamate Receptor
- neurotransmission
- oxidative stress
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Affiliation(s)
| | - Christopher F. Rose
- Address for correspondence. Christopher F. Rose Professor, Dept. Medicine, Université de Montréal, CRCHUM, 900 Saint-Denis Street, Montréal, Québec, H2X 0A9, Canada.
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Cabrera-Pastor A, Balzano T, Hernández-Rabaza V, Malaguarnera M, Llansola M, Felipo V. Increasing extracellular cGMP in cerebellum in vivo reduces neuroinflammation, GABAergic tone and motor in-coordination in hyperammonemic rats. Brain Behav Immun 2018; 69:386-398. [PMID: 29288802 DOI: 10.1016/j.bbi.2017.12.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 12/21/2017] [Accepted: 12/26/2017] [Indexed: 11/28/2022] Open
Abstract
Hyperammonemia is a main contributor to cognitive impairment and motor in-coordination in patients with hepatic encephalopathy. Hyperammonemia-induced neuroinflammation mediates the neurological alterations in hepatic encephalopathy. Intracerebral administration of extracellular cGMP restores some but not all types of cognitive impairment. Motor in-coordination, is mainly due to increased GABAergic tone in cerebellum. We hypothesized that extracellular cGMP would restore motor coordination in hyperammonemic rats by normalizing GABAergic tone in cerebellum and that this would be mediated by reduction of neuroinflammation. The aims of this work were to assess whether chronic intracerebral administration of cGMP to hyperammonemic rats: 1) restores motor coordination; 2) reduces neuroinflammation in cerebellum; 3) reduces extracellular GABA levels and GABAergic tone in cerebellum; and also 4) to provide some advance in the understanding on the molecular mechanisms involved. The results reported show that rats with chronic hyperammonemia show neuroinflammation in cerebellum, including microglia and astrocytes activation and increased levels of IL-1b and TNFa and increased membrane expression of the TNFa receptor. This is associated with increased glutaminase expression and extracellular glutamate, increased amount of the GABA transporter GAT-3 in activated astrocytes, increased extracellular GABA in cerebellum and motor in-coordination. Chronic intracerebral administration of extracellular cGMP to rats with chronic hyperammonemia reduces neuroinflammation, including microglia and astrocytes activation and membrane expression of the TNFa receptor. This is associated with reduced nuclear NF-κB, glutaminase expression and extracellular glutamate, reduced amount of the GABA transporter GAT-3 in activated astrocytes and reduced extracellular GABA in cerebellum and restoration of motor coordination. The data support that extracellular cGMP restores motor coordination in hyperammonemic rats by reducing microglia activation and neuroinflammation, leading to normalization of extracellular glutamate and GABA levels in cerebellum and of motor coordination.
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Affiliation(s)
- Andrea Cabrera-Pastor
- Laboratorio de Neurobiología, Centro Investigación Príncipe Felipe de Valencia, Spain
| | - Tiziano Balzano
- Laboratorio de Neurobiología, Centro Investigación Príncipe Felipe de Valencia, Spain
| | | | - Michele Malaguarnera
- Laboratorio de Neurobiología, Centro Investigación Príncipe Felipe de Valencia, Spain
| | - Marta Llansola
- Laboratorio de Neurobiología, Centro Investigación Príncipe Felipe de Valencia, Spain
| | - Vicente Felipo
- Laboratorio de Neurobiología, Centro Investigación Príncipe Felipe de Valencia, Spain.
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Balzano T, Forteza J, Molina P, Giner J, Monzó A, Sancho-Jiménez J, Urios A, Montoliu C, Felipo V. The Cerebellum of Patients with Steatohepatitis Shows Lymphocyte Infiltration, Microglial Activation and Loss of Purkinje and Granular Neurons. Sci Rep 2018; 8:3004. [PMID: 29445232 PMCID: PMC5813099 DOI: 10.1038/s41598-018-21399-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 02/05/2018] [Indexed: 12/21/2022] Open
Abstract
Peripheral inflammation contributes to minimal hepatic encephalopathy in chronic liver diseases, which could be mediated by neuroinflammation. Neuroinflammation in cerebellum of patients with chronic liver diseases has not been studied in detail. Our aim was to analyze in cerebellum of patients with different grades of liver disease, from mild steatohepatitis to cirrhosis and hepatic encephalopathy: (a) neuronal density in Purkinje and granular layers; (b) microglial activation; (c) astrocyte activation; (d) peripheral lymphocytes infiltration; (e) subtypes of lymphocytes infiltrated. Steatohepatitis was classified as SH1, SH2 and SH3. Patients with SH1 show Th17 and Tfh lymphocytes infiltration in the meninges, microglia activation in the molecular layer and loss of 16 ± 4% of Purkinje and 19 ± 2% of granular neurons. White matter remains unaffected. With the progression of liver disease to worse stages (SH2, SH3, cirrhosis) activation of microglia and astrocytes extends to white matter, Bergman glia is damaged in the molecular layer and there is a further loss of Purkinje neurons. The results reported show that neuroinflammation in cerebellum occurs at early stages of liver disease, even before reaching cirrhosis. Neuroinflammation occurs earlier in the molecular layer than in white matter, and is associated with infiltration of peripheral Th17 and Tfh lymphocytes.
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Affiliation(s)
- Tiziano Balzano
- Laboratory of Neurobiology, Centro Investigación Príncipe Felipe, Valencia, Spain
| | - Jerónimo Forteza
- Instituto Valenciano de Patología, Unidad Mixta de Patología Molecular. CIPF/Universidad Católica, Valencia, Spain
| | - Pilar Molina
- Instituto de Medicina Legal y Ciencias Forenses, Valencia, Spain.,Departamento de Patología, Facultad de Medicina, Universidad Valencia, Valencia, Spain
| | - Juan Giner
- Instituto de Medicina Legal y Ciencias Forenses, Valencia, Spain
| | - Ana Monzó
- Instituto de Medicina Legal y Ciencias Forenses, Valencia, Spain
| | | | - Amparo Urios
- Laboratory of Neurobiology, Centro Investigación Príncipe Felipe, Valencia, Spain
| | - Carmina Montoliu
- Departamento de Patología, Facultad de Medicina, Universidad Valencia, Valencia, Spain.,Instituto de Investigación Sanitaria-INCLIVA, Valencia, Spain
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro Investigación Príncipe Felipe, Valencia, Spain.
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Taoro-Gonzalez L, Arenas YM, Cabrera-Pastor A, Felipo V. Hyperammonemia alters membrane expression of GluA1 and GluA2 subunits of AMPA receptors in hippocampus by enhancing activation of the IL-1 receptor: underlying mechanisms. J Neuroinflammation 2018; 15:36. [PMID: 29422059 PMCID: PMC5806265 DOI: 10.1186/s12974-018-1082-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Accepted: 01/29/2018] [Indexed: 11/13/2022] Open
Abstract
Background Hyperammonemic rats reproduce the cognitive alterations of patients with hepatic encephalopathy, including altered spatial memory, attributed to altered membrane expression of AMPA receptor subunits in hippocampus. Neuroinflammation mediates these cognitive alterations. We hypothesized that hyperammonemia-induced increase in IL-1β in hippocampus would be responsible for the altered GluA1 and GluA2 membrane expression. The aims of this work were to (1) assess if increased IL-1β levels and activation of its receptor are responsible for the changes in GluA1 and/or GluA2 membrane expression in hyperammonemia and (2) identify the mechanisms by which activation of IL-1 receptor leads to altered membrane expression of GluA1 and GluA2. Methods We analyzed in hippocampal slices from control and hyperammonemic rat membrane expression of AMPA receptors using the BS3 cross-linker and phosphorylation of the GluA1 and GluA2 subunits using phosphor-specific antibodies. The IL-1 receptor was blocked with IL-Ra, and the signal transduction pathways involved in modulation of membrane expression of GluA1 and GluA2 were analyzed using inhibitors of key steps. Results Hyperammonemia reduces GluA1 and increases GluA2 membrane expression and reduces phosphorylation of GluA1 at Ser831 and of GluA2 at Ser880. Hyperammonemia increases IL-1β, enhancing activation of IL-1 receptor. This leads to activation of Src. The changes in membrane expression of GluA1 and GluA2 are reversed by blocking the IL-1 receptor with IL-1Ra or by inhibiting Src with PP2. After Src activation, the pathways for GluA2 and GluA1 diverge. Src increases phosphorylation of GluN2B at Tyr14721 and membrane expression of GluN2B in hyperammonemic rats, leading to activation of MAP kinase p38, which binds to and reduces phosphorylation at Thr560 and activity of PKCζ, resulting in reduced phosphorylation at Ser880 and enhanced membrane expression of GluA2. Increased Src activity in hyperammonemic rats also activates PKCδ which enhances phosphorylation of GluN2B at Ser1303, reducing membrane expression of CaMKII and phosphorylation at Ser831 and membrane expression of GluA1. Conclusions This work identifies two pathways by which neuroinflammation alters glutamatergic neurotransmission in hippocampus. The steps of the pathways identified could be targets to normalize neurotransmission in hyperammonemia and other pathologies associated with increased IL-1β by acting, for example, on p38 or PKCδ. Graphical abstract IL-1β alters membrane expression of GluA1 and GluA2 AMPA receptor subunits by two difrerent mechanisms in the hippocampus of hyperammonemic rats.
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Affiliation(s)
- Lucas Taoro-Gonzalez
- Laboratory of Neurobiology, Centro de Investigacion Príncipe Felipe, Eduardo Primo Yufera 3, 46012, Valencia, Spain.
| | - Yaiza M Arenas
- Laboratory of Neurobiology, Centro de Investigacion Príncipe Felipe, Eduardo Primo Yufera 3, 46012, Valencia, Spain
| | - Andrea Cabrera-Pastor
- Laboratory of Neurobiology, Centro de Investigacion Príncipe Felipe, Eduardo Primo Yufera 3, 46012, Valencia, Spain
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigacion Príncipe Felipe, Eduardo Primo Yufera 3, 46012, Valencia, Spain
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Abstract
Hepatic encephalopathy describes the array of neurological alterations that occur during acute liver failure or chronic liver injury. While key players in the pathogenesis of hepatic encephalopathy, such as increases in brain ammonia, alterations in neurosteroid levels, and neuroinflammation, have been identified, there is still a paucity in our knowledge of the precise pathogenic mechanism. This review gives a brief overview of our understanding of the pathogenesis of hepatic encephalopathy and then summarizes the significant recent advances made in clinical and basic research contributing to our understanding, diagnosis, and possible treatment of hepatic encephalopathy. A literature search using the PubMed database was conducted in May 2017 using "hepatic encephalopathy" as a keyword, and selected manuscripts were limited to those research articles published since May 2014. While the authors acknowledge that many significant advances have been made in the understanding of hepatic encephalopathy prior to May 2014, we have limited the scope of this review to the previous three years only.
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Affiliation(s)
- Victoria Liere
- Department of Medical Physiology, College of Medicine, Texas A&M Health Science Center, Temple, TX, USA
| | | | - Sharon DeMorrow
- Department of Medical Physiology, College of Medicine, Texas A&M Health Science Center, Temple, TX, USA
- Central Texas Veterans Healthcare System, Temple, TX, USA
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Agusti A, Hernández-Rabaza V, Balzano T, Taoro-Gonzalez L, Ibañez-Grau A, Cabrera-Pastor A, Fustero S, Llansola M, Montoliu C, Felipo V. Sildenafil reduces neuroinflammation in cerebellum, restores GABAergic tone, and improves motor in-coordination in rats with hepatic encephalopathy. CNS Neurosci Ther 2017; 23:386-394. [PMID: 28296282 DOI: 10.1111/cns.12688] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 01/23/2017] [Accepted: 02/09/2017] [Indexed: 12/31/2022] Open
Abstract
AIMS Patients with liver disease may develop hepatic encephalopathy (HE), with cognitive impairment and motor in-coordination. Rats with HE due to portacaval shunts (PCS) show motor in-coordination. We hypothesized that in PCS rats: (i) Motor in-coordination would be due to enhanced GABAergic tone in cerebellum; (ii) increased GABAergic tone would be due to neuroinflammation; (iii) increasing cGMP would reduce neuroinflammation and GABAergic tone and restore motor coordination. To assess these hypotheses, we assessed if (i) treatment with sildenafil reduces neuroinflammation; (ii) reduced neuroinflammation is associated with reduced GABAergic tone and restored motor coordination. METHODS Rats were treated with sildenafil to increase cGMP. Microglia and astrocytes activation were analyzed by immunohistochemistry, extracellular GABA by microdialysis, and motor coordination in the beam walking. RESULTS PCS rats show neuroinflammation in cerebellum, with microglia and astrocytes activation, increased IL-1b and TNF-a and reduced YM-1 and IL-4. Membrane expression of the GABA transporter GAT1 is reduced, while GAT3 is increased. Extracellular GABA and motor in-coordination are increased. Sildenafil treatment eliminates neuroinflammation, microglia and astrocytes activation; changes in membrane expression of GABA transporters; and restores motor coordination. CONCLUSIONS This study supports an interplay between cGMP-neuroinflammation and GABAergic neurotransmission in impairing motor coordination in PCS rats.
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Affiliation(s)
- Ana Agusti
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | | | - Tiziano Balzano
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Lucas Taoro-Gonzalez
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Andrea Ibañez-Grau
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Andrea Cabrera-Pastor
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Santos Fustero
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Marta Llansola
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Carmina Montoliu
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
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