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El-Mansoury B, Smimih K, El Khiat A, Draoui A, Aimrane A, Chatoui R, Ferssiwi A, Bitar A, Gamrani H, Jayakumar AR, El Hiba O. Short Working Memory Impairment Associated with Hippocampal Microglia Activation in Chronic Hepatic Encephalopathy. Metabolites 2024; 14:193. [PMID: 38668321 PMCID: PMC11052478 DOI: 10.3390/metabo14040193] [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: 10/29/2023] [Revised: 01/03/2024] [Accepted: 01/06/2024] [Indexed: 04/28/2024] Open
Abstract
Hepatic encephalopathy (HE) is a major neuropsychological condition that occursas a result of impaired liver function. It is frequently observed in patients with advanced liver disease or cirrhosis. Memory impairment is among the symptoms of HE; the pathophysiologic mechanism for this enervating condition remains unclear. However, it is possible that neuroinflammation may be involved, as recent studies have emphasized such phenomena. Therefore, the aim of the present study is to assess short working memory (SWM) and examine the involvement of microglia in a chronic model of HE. The study was carried out with male Wistar rats that were induced by repeated thioacetamide (TAA) administration (100 mg/kg i.p injection for 10 days). SWM function was assessed through Y-maze, T-Maze, and novel object recognition (NOR) tests, together with an immunofluorescence study of microglia activation within the hippocampal areas. Our data showed impaired SWM in TAA-treated rats that was associated with microglial activation in the three hippocampal regions, and which contributed to cognitive impairment.
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Affiliation(s)
- Bilal El-Mansoury
- Laboratory of Anthropogenic, Biotechnology and Health, Nutritional Physiopathologies, Neurosciences and Toxicology Team, Faculty of Sciences, Chouaib Doukkali University, Av. Des Facultés, El Jadida 24000, Morocco; (B.E.-M.); (A.E.K.); (A.A.); (A.F.); (A.B.)
| | - Kamal Smimih
- Laboratory of Genie-Biology, Faculty of Sciences and Techniques, Sultan Moulay Slimane University, Beni Mellal 23000, Morocco; (K.S.); (R.C.)
| | - Abdelaati El Khiat
- Laboratory of Anthropogenic, Biotechnology and Health, Nutritional Physiopathologies, Neurosciences and Toxicology Team, Faculty of Sciences, Chouaib Doukkali University, Av. Des Facultés, El Jadida 24000, Morocco; (B.E.-M.); (A.E.K.); (A.A.); (A.F.); (A.B.)
- Higher Institute of Nursing Professions and Health Techniques, Ministry of Health, Ouarzazate 45000, Morocco
- Laboratory of Clinical and Experimental Neurosciences and Environment, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakech 40000, Morocco
| | - Ahmed Draoui
- Laboratory of Clinical and Experimental Neurosciences and Environment, Faculty of Science Semlalia, Cadi Ayyad University, Marrakech 40000, Morocco; (A.D.); (H.G.)
| | - Abdelmohcine Aimrane
- Laboratory of Anthropogenic, Biotechnology and Health, Nutritional Physiopathologies, Neurosciences and Toxicology Team, Faculty of Sciences, Chouaib Doukkali University, Av. Des Facultés, El Jadida 24000, Morocco; (B.E.-M.); (A.E.K.); (A.A.); (A.F.); (A.B.)
| | - Redouane Chatoui
- Laboratory of Genie-Biology, Faculty of Sciences and Techniques, Sultan Moulay Slimane University, Beni Mellal 23000, Morocco; (K.S.); (R.C.)
| | - Abdesslam Ferssiwi
- Laboratory of Anthropogenic, Biotechnology and Health, Nutritional Physiopathologies, Neurosciences and Toxicology Team, Faculty of Sciences, Chouaib Doukkali University, Av. Des Facultés, El Jadida 24000, Morocco; (B.E.-M.); (A.E.K.); (A.A.); (A.F.); (A.B.)
| | - Abdelali Bitar
- Laboratory of Anthropogenic, Biotechnology and Health, Nutritional Physiopathologies, Neurosciences and Toxicology Team, Faculty of Sciences, Chouaib Doukkali University, Av. Des Facultés, El Jadida 24000, Morocco; (B.E.-M.); (A.E.K.); (A.A.); (A.F.); (A.B.)
| | - Halima Gamrani
- Laboratory of Clinical and Experimental Neurosciences and Environment, Faculty of Science Semlalia, Cadi Ayyad University, Marrakech 40000, Morocco; (A.D.); (H.G.)
| | | | - Omar El Hiba
- Laboratory of Anthropogenic, Biotechnology and Health, Nutritional Physiopathologies, Neurosciences and Toxicology Team, Faculty of Sciences, Chouaib Doukkali University, Av. Des Facultés, El Jadida 24000, Morocco; (B.E.-M.); (A.E.K.); (A.A.); (A.F.); (A.B.)
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Sahin B, Karabulut S, Filiz AK, Özkaraca M, Gezer A, Akpulat HA, Ataseven H. Galium aparine L. protects against acetaminophen-induced hepatotoxicity in rats. Chem Biol Interact 2022; 366:110119. [PMID: 36029804 DOI: 10.1016/j.cbi.2022.110119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 08/08/2022] [Accepted: 08/16/2022] [Indexed: 11/25/2022]
Abstract
The toxicity of acetaminophen (N-acetyl-para-aminophenol (APAP)) is the most frequent cause of drug-induced liver damage. Galium aparine L. (GA) is traditionally used to treat jaundice. We aimed to investigate the hepatoprotective potential of GA in the APAP-induced hepatic encephalopathy (HE) rat model. Qualitative phytochemical characterization of GA was performed by LC/Q-TOF/MS analysis. Wistar rats were pretreated with GA (250 and 500 mg/kg b.wt. per oral) for five days. On the 6th day, the rats were exposed to APAP (1500 mg/kg b.wt. oral gavage) and behavioral tests (open field and passive avoidance tests) were applied on the 7th and 8th days. The animals were killed, and biochemical and histopathological parameters were assessed in blood and hepatic specimens. GA pretreated rats exhibited a significant reduction in APAP-induced liver damage, evidenced by the reduction in liver necrosis and alanine aminotransferase (ALT), aspartate aminotransferase (AST), and bilirubin (BIL). GA demonstrated an anxiolytic effect, as seen in the acquisition trial and grooming behavior. The short-term memory performances of animals were not changed in all groups, suggesting that APAP intoxication did not affect hippocampal function. These results show that GA extract markedly exerts hepatoprotective activity, while its effect on hepatic encephalopathy was limited.
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Affiliation(s)
- Bilal Sahin
- Department of Medical Physiology, Faculty of Medicine, Sivas Cumhuriyet University, Sivas, Turkey
| | - Sebahattin Karabulut
- Department of Medical Services and Techniques, Vocational School of Health Services, Sivas Cumhuriyet University, Sivas, Turkey.
| | - Ahmet Kemal Filiz
- Department of Medical Physiology, Faculty of Medicine, Sivas Cumhuriyet University, Sivas, Turkey
| | - Mustafa Özkaraca
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, Sivas Cumhuriyet University, Sivas, Turkey
| | - Arzu Gezer
- Department of Health Care Services, Vocational School of Health Services, Atatürk University, Erzurum, Turkey
| | | | - Hilmi Ataseven
- Department of Internal Medicine, Discipline of Gastroenterology, Faculty of Medicine, Sivas Cumhuriyet University, Sivas, Turkey
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Ghobadi Pour M, Mirazi N, Alaei H, Radahmadi M, Rajaei Z, Monsef Esfahani A. The effects of concurrent treatment of silymarin and lactulose on memory changes in cirrhotic male rats. ACTA ACUST UNITED AC 2020; 10:177-186. [PMID: 32793440 PMCID: PMC7416014 DOI: 10.34172/bi.2020.22] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 11/30/2019] [Accepted: 12/14/2019] [Indexed: 12/17/2022]
Abstract
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Introduction: Chronic liver disease frequently accompanied by hepatic encephalopathy (HE). Changes in the permeability of the blood-brain barrier in HE, make an easier entrance of ammonia among other substances to the brain, which leads to neurotransmitter disturbances. Lactulose (LAC), causes better defecation and makes ammonia outreach of blood. Silymarin (SM) is a known standard drug for liver illnesses. The purpose of this research was to determine the results of LAC and SM combined treatment, on the changes in memory of cirrhotic male rats. Methods: The cirrhotic model established by treatment with thioacetamide (TAA) for 18 weeks. Cirrhotic rats randomized to four groups (n = 7): TAA group (received drinking water), LAC group (2 g/kg/d LAC in drinking water), SM group (50 mg/kg/d SM by food), SM+ LAC group (similar combined doses of both compounds) for 8 weeks. The control group received drinking water. The behavior examined by wire hanging (WH), passive avoidance (PA), and open field (OF) tests.
Results: Our findings showed that treatment with SM+LAC effectively increased PA latency, compared with the control group. The results showed that the administration of LAC and SM+LAC affected the number of lines crossed, the total distance moved and velocity in the OF tests. Conclusion: SM and LAC have anti-inflammatory effects that are memory changing. It may be due to their useful effects. These results indicated that SM+LAC restored memory disturbance and irritated mood in the cirrhotic rats. Comparable neuroprotection was never previously informed. Such outcomes are extremely promising and indicate the further study of SM+LAC.
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Affiliation(s)
- Mozhgan Ghobadi Pour
- Department of Biology, Faculty of Basic Sciences, Bu-Ali Sina University, Hamedan, Iran
| | - Naser Mirazi
- Department of Biology, Faculty of Basic Sciences, Bu-Ali Sina University, Hamedan, Iran
| | - Hojatollah Alaei
- Department of Physiology, Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Maryam Radahmadi
- Department of Physiology, Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Ziba Rajaei
- Department of Physiology, Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
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Banqueri M, Méndez M, Arias JL. Behavioral effects in adolescence and early adulthood in two length models of maternal separation in male rats. Behav Brain Res 2017; 324:77-86. [DOI: 10.1016/j.bbr.2017.02.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 01/30/2017] [Accepted: 02/04/2017] [Indexed: 12/11/2022]
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Nasehi M, Mafi F, Ebrahimi-Ghiri M, Zarrindast MR. Function of opioidergic and dopaminergic antagonists on both spatial and object novelty detection deficits induced in rodent model of hepatic encephalopathy. Behav Brain Res 2016; 313:58-66. [DOI: 10.1016/j.bbr.2016.07.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 07/05/2016] [Accepted: 07/07/2016] [Indexed: 01/27/2023]
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Low-light-level therapy as a treatment for minimal hepatic encephalopathy: behavioural and brain assessment. Lasers Med Sci 2016; 31:1717-1726. [DOI: 10.1007/s10103-016-2042-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 07/27/2016] [Indexed: 12/15/2022]
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Tamaoki S, Suzuki H, Okada M, Fukui N, Isobe M, Saito T. Development of an experimental rat model of hyperammonemic encephalopathy and evaluation of the effects of rifaximin. Eur J Pharmacol 2016; 779:168-76. [DOI: 10.1016/j.ejphar.2016.03.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 03/10/2016] [Accepted: 03/11/2016] [Indexed: 02/07/2023]
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8
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Bodega G, Segura B, Ciordia S, Mena MDC, López-Fernández LA, García MI, Trabado I, Suárez I. Ammonia Affects Astroglial Proliferation in Culture. PLoS One 2015; 10:e0139619. [PMID: 26421615 PMCID: PMC4589356 DOI: 10.1371/journal.pone.0139619] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 09/14/2015] [Indexed: 11/19/2022] Open
Abstract
Primary cultures of rat astroglial cells were exposed to 1, 3 and 5 mM NH4Cl for up to 10 days. Dose- and time-dependent reductions in cell numbers were seen, plus an increase in the proportion of cells in the S phase. The DNA content was reduced in the treated cells, and BrdU incorporation diminished. However, neither ammonia nor ammonia plus glutamine had any effect on DNA polymerase activity. iTRAQ analysis showed that exposure to ammonia induced a significant reduction in histone and heterochromatin protein 1 expression. A reduction in cell viability was also noted. The ammonia-induced reduction of proliferative activity in these cultured astroglial cells seems to be due to a delay in the completion of the S phase provoked by the inhibition of chromatin protein synthesis.
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Affiliation(s)
- Guillermo Bodega
- Departamento de Biomedicina y Biotecnología, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain
- * E-mail:
| | - Berta Segura
- Instituto de Salud Carlos III, UFIEC, Unidad de Neuro-Oncología, 28220 Majadahonda, Madrid, Spain
| | - Sergio Ciordia
- Proteomics, Centro Nacional de Biotecnología/CSIC, Campus de Cantoblanco, Madrid, Spain
| | - María del Carmen Mena
- Proteomics, Centro Nacional de Biotecnología/CSIC, Campus de Cantoblanco, Madrid, Spain
| | - Luis Andrés López-Fernández
- Servicio de Farmacia, Instituto de Investigación Sanitaria Gregorio Marañón, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - María Isabel García
- Servicio de Farmacia, Instituto de Investigación Sanitaria Gregorio Marañón, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Isabel Trabado
- Unidad de Cultivos, Facultad de Medicina, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain
| | - Isabel Suárez
- Departamento de Biomedicina y Biotecnología, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain
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Schroeter A, Wen S, Mölders A, Erlenhardt N, Stein V, Klöcker N. Depletion of the AMPAR reserve pool impairs synaptic plasticity in a model of hepatic encephalopathy. Mol Cell Neurosci 2015; 68:331-9. [DOI: 10.1016/j.mcn.2015.09.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 07/22/2015] [Accepted: 09/06/2015] [Indexed: 02/07/2023] Open
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Main target of minimal hepatic encephalopathy: Morphophysiological, inflammatory and metabolic view. Physiol Behav 2015; 149:247-54. [PMID: 26079568 DOI: 10.1016/j.physbeh.2015.06.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 03/25/2015] [Accepted: 06/10/2015] [Indexed: 12/12/2022]
Abstract
Although often not considered clinically relevant and, therefore, not diagnosed or treated, minimal hepatic encephalopathy (MHE) has been shown to affect daily functioning, quality of life, driving and overall mortality. To discover early impairments involved in MHE, we studied one of its precipitating factors, portal hypertension. Rats were trained on a stimulus-response task using the Morris water maze. Two groups of animals were used: a SHAM (sham-operated) group (n= 13) and a portal hypertension (PH) group (n= 13). The triple portal vein ligation method was used to create an animal model of an early developmental phase of HE. Brain metabolic activity was studied with cytochrome c-oxidase histochemistry (C.O.). Neuronal nuclear volume was assessed by nucleator probe; the number of glial fibrillary acidic protein-immunoreactive astrocytes (GFAP-IR) and proinflammatory mediators was measured. The results revealed that the PH group was not able to reach the behavioural criterion, in contrast to the SHAM group. The metabolic brain consumption revealed decreased C.O. activity in the ventral striatum. The PH group showed lower density of GFAP-IR and an increase in the tumour necrotic factor-α (TNF-α). The PH group showed decreased neuronal nuclear volume in the dorsal striatum. On the contrary, increased neuronal nuclear volume was found in the ventral striatum. For the first time, a relationship has been established between inflammation, astrocytic and neural damage, and brain metabolic impairment in a model of MHE. Disruption of the striatum and related structures was highlighted as the main target in early stages of HE. Finally, a simple task was presented to assess the subtle impairments found in the clinic, which could provide fresh insights into the development of new tools for the assessment of MHE.
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Méndez-López M, Méndez M, Arias J, Arias JL. Effects of a high protein diet on cognition and brain metabolism in cirrhotic rats. Physiol Behav 2015; 149:220-8. [PMID: 26048304 DOI: 10.1016/j.physbeh.2015.05.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 05/28/2015] [Accepted: 05/29/2015] [Indexed: 12/12/2022]
Abstract
Hepatic encephalopathy (HE) is a neurological complication observed in patients with liver disease. Patients who suffer from HE present neuropsychiatric, neuromuscular and behavioral symptoms. Animal models proposed to study HE resulting from cirrhosis mimic the clinical characteristics of cirrhosis and portal hypertension, and require the administration of hepatotoxins such as thioacetamide (TAA). The aim of this study was to assess the effects of a high protein diet on motor function, anxiety and memory processes in a model of cirrhosis induced by TAA administration. In addition, we used cytochrome c-oxidase (COx) histochemistry to assess the metabolic activity of the limbic system regions. Male rats were distributed into groups: control, animals with cirrhosis, Control rats receiving a high protein diet, and animals with cirrhosis receiving a high protein diet. Results showed preserved motor function and normal anxiety levels in all the groups. The animals with cirrhosis showed an impairment in active avoidance behavior and spatial memory, regardless of the diet they received. However, the animals with cirrhosis and a high protein diet showed longer escape latencies on the spatial memory task. The model of cirrhosis presented an under-activation of the dentate gyrus and CA3 hippocampal subfields and the medial part of the medial mammillary nucleus. The results suggest that a high protein intake worsens spatial memory deficits shown by the TAA-induced model of cirrhosis. However, high protein ingestion has no influence on the COx hypoactivity associated with the model.
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Affiliation(s)
- M Méndez-López
- Department of Psychology, University of Zaragoza, Campus Ciudad Escolar s/n., 44003 Teruel, Spain.
| | - M Méndez
- Laboratory of Neuroscience, Department of Psychology, Instituto de Neurociencias del Principado de Asturias (INEUROPA), University of Oviedo, Plaza Feijóo s/n., 33003 Oviedo, Spain.
| | - J Arias
- Faculty of Medicine, Complutense University of Madrid, Ciudad Universitaria s/n., 28040 Madrid, Spain.
| | - J L Arias
- Laboratory of Neuroscience, Department of Psychology, Instituto de Neurociencias del Principado de Asturias (INEUROPA), University of Oviedo, Plaza Feijóo s/n., 33003 Oviedo, Spain.
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Chepkova AN, Sergeeva OA, Haas HL. Alterations of corticostriatal plasticity by ammonium and rescue by green tea polyphenols. Arch Biochem Biophys 2013; 536:176-82. [DOI: 10.1016/j.abb.2013.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 01/31/2013] [Accepted: 02/05/2013] [Indexed: 01/22/2023]
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13
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Leke R, Oliveira DL, Forgiarini LF, Escobar TDC, Hammes TO, Meyer FS, Keiding S, Silveira TR, Schousboe A. Impairment of short term memory in rats with hepatic encephalopathy due to bile duct ligation. Metab Brain Dis 2013; 28:187-92. [PMID: 23111918 DOI: 10.1007/s11011-012-9347-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 10/15/2012] [Indexed: 12/12/2022]
Abstract
Hepatic encephalopathy (HE) arises from acute or chronic liver diseases and leads to cognitive deficits. Different animal models for the study of HE have demonstrated learning and memory impairment and a number of neurotransmitter systems have been proposed to be involved in this. Recently, it was described that bile duct-ligated (BDL) rats exhibited altered spatio-temporal locomotor and exploratory activities and biosynthesis of neurotransmitter GABA in brain cortices. Therefore, the aim of this study was to evaluate cognition in the same animal model. Male adult Wistar rats underwent common bile duct ligation (BDL rats) or manipulation of common bile duct without ligation (control rats). Six weeks after surgery, control and BDL rats underwent object recognition behavioral task. The BDL rats developed chronic liver failure and exhibited a decreased discrimination index for short term memory (STM) when compared to the control group. There was no difference in long term memory (LTM) as well as in total time of exploration in the training, STM and LTM sessions between the BDL and control rats. Therefore, the BDL rats demonstrated impaired STM for recognition memory, which was not due to decreased exploration.
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Affiliation(s)
- Renata Leke
- Experimental Hepatology and Gastroenterology Laboratory, Research Center of Hospital de Clínicas de Porto Alegre, Avenida Ramiro Barcelos, 2350, Porto Alegre, Rio Grande do Sul 90035-903, Brazil.
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Wen S, Schroeter A, Klöcker N. Synaptic plasticity in hepatic encephalopathy - a molecular perspective. Arch Biochem Biophys 2013; 536:183-8. [PMID: 23624147 DOI: 10.1016/j.abb.2013.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 04/13/2013] [Accepted: 04/15/2013] [Indexed: 01/04/2023]
Abstract
Hepatic encephalopathy (HE)(1) is a common neuropsychiatric complication of both acute and chronic liver disease. Clinical symptoms may include motor disturbances and cognitive dysfunction. Available animal models of HE mimic the deficits in cognitive performance including the impaired ability to learn and memorize information. This review explores the question how HE might affect cognitive functions at molecular levels. Both acute and chronic models of HE constrain the plasticity of glutamatergic neurotransmission. Thus, long-lasting activity-dependent changes in synaptic efficiency, known as long-term potentiation (LTP) and long-term depression (LTD) are significantly impeded. We discuss molecules and signal transduction pathways of LTP and LTD that are targeted by experimental HE, with a focus on ionotropic glutamate receptors of the AMPA-subtype. Finally, a novel strategy of functional proteomic analysis is presented, which, if applied differentially, may provide molecular insight into disease-related dysfunction of membrane protein complexes, i.e. disturbed ionotropic glutamate receptor signaling in HE.
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Affiliation(s)
- Shuping Wen
- Institute of Neural and Sensory Physiology, Medical Faculty, University of Düsseldorf D-40225 Düsseldorf, Germany
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15
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Mapping metabolic brain activity in three models of hepatic encephalopathy. Int J Hypertens 2013; 2013:390872. [PMID: 23573412 PMCID: PMC3612461 DOI: 10.1155/2013/390872] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Accepted: 02/19/2013] [Indexed: 11/17/2022] Open
Abstract
Cirrhosis is a common disease in Western countries. Liver failure, hyperammonemia, and portal hypertension are the main factors that contribute to human cirrhosis that frequently leads to a neuropsychiatric disorder known as hepatic encephalopathy (HE). In this study, we examined the differential contribution of these leading factors to the oxidative metabolism of diverse brain limbic system regions frequently involved in memory process by histochemical labelling of cytochrome oxidase (COx). We have analyzed cortical structures such as the infralimbic and prelimbic cotices, subcortical structures such as hippocampus and ventral striatum, at thalamic level like the anterodorsal, anteroventral, and mediodorsal thalamus, and, finally, the hypothalamus, where the mammillary nuclei (medial and lateral) were measured. The severest alteration is found in the model that mimics intoxication by ammonia, followed by the thioacetamide-treated group and the portal hypertension group. No changes were found at the mammillary bodies for any of the experimental groups.
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Effects of dopamine receptor agonist and antagonists on cholestasis-induced anxiolytic-like behaviors in rats. Eur J Pharmacol 2013; 702:25-31. [DOI: 10.1016/j.ejphar.2013.01.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 12/20/2012] [Accepted: 01/15/2013] [Indexed: 01/08/2023]
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Chepkova AN, Selbach O, Haas HL, Sergeeva OA. Ammonia-induced deficit in corticostriatal long-term depression and its amelioration by zaprinast. J Neurochem 2012; 122:545-56. [PMID: 22639911 DOI: 10.1111/j.1471-4159.2012.07806.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hyperammonemia is a major pathophysiological factor in encephalopathies associated with acute and chronic liver failure. On mouse brain slice preparations, we analyzed the effects of ammonia on the characteristics of corticostriatal long-term depression (LTD) induced by electrical stimulation of cortical input or pharmacological activation of metabotropic glutamate receptors. Long exposure of neostriatal slices to ammonium chloride impaired the induction and/or expression of all studied forms of LTD. This impairment was reversed by the phosphodiesterase inhibitor zaprinast implying lowered cGMP signaling in LTD suppression. Polyphenols from green tea rescued short-term corticostriatal plasticity, but failed to prevent the ammonia-induced deficit of LTD. Zaprinast counteracts the ammonia-induced impairment of long-term corticostriatal plasticity and may thus improve fine motor skills and procedural learning in hepatic encephalopathy.
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Affiliation(s)
- Aisa N Chepkova
- Department of Neurophysiology, Medical Faculty, Heinrich-Heine-University, Dusseldorf, Germany
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Arias N, Méndez M, Arias J, Arias JL. Brain metabolism and spatial memory are affected by portal hypertension. Metab Brain Dis 2012; 27:183-91. [PMID: 22314871 DOI: 10.1007/s11011-012-9276-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 01/19/2012] [Indexed: 11/24/2022]
Abstract
Portal hypertension is a major complication of cirrhosis that frequently leads to a neuropsychiatric disorder that affects cognition. The present study was undertaken in order to compare the performance of sham-operated rats (SHAM) and portal hypertension rats (PH) in reference memory tasks in the Morris water maze (MWM). Two groups of animals were used: SHAM group (n=12) was used as a control group and PH group (n=12) by the triple portal vein ligation method was used as an animal model of early evolutive phase of PH. The portal pressure was measured in the splenic parenchyma. Our work shows that spatial learning in the MWM is not impaired in PH group although this group showed a one-day delay in the task acquisition compared to the SHAM group. We assessed the brain metabolic activity of the animals by means of cytochrome c-oxidase (COx) histochemistry. Significant changes were found in the CA3, dentate gyrus, basolateral, medial, lateral and central amygdala, showing lower COx activity in the PH group as compared to the SHAM group in all cases. We found no changes in metabolic activity in prefrontal cortex and CA1 area between groups. In fact, different neural networks were shown according to the execution level of the subjects. The early PH evolution induced changes in brain metabolic activity without biggest alterations in spatial memory.
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Affiliation(s)
- Natalia Arias
- Laboratorio de Neurociencias, Departamento de Psicología, Universidad de Oviedo, Asturias, Spain
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19
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Leke R, de Oliveira DL, Mussulini BHM, Pereira MS, Kazlauckas V, Mazzini G, Hartmann CR, Silveira TR, Simonsen M, Bak LK, Waagepetersen HS, Keiding S, Schousboe A, Portela LV. Impairment of the organization of locomotor and exploratory behaviors in bile duct-ligated rats. PLoS One 2012; 7:e36322. [PMID: 22586467 PMCID: PMC3346757 DOI: 10.1371/journal.pone.0036322] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 03/30/2012] [Indexed: 12/16/2022] Open
Abstract
Hepatic encephalopathy (HE) arises from acute or chronic liver diseases and leads to several problems, including motor impairment. Animal models of chronic liver disease have extensively investigated the mechanisms of this disease. Impairment of locomotor activity has been described in different rat models. However, these studies are controversial and the majority has primarily analyzed activity parameters. Therefore, the aim of the present study was to evaluate locomotor and exploratory behavior in bile duct-ligated (BDL) rats to explore the spatial and temporal structure of behavior. Adult female Wistar rats underwent common bile duct ligation (BDL rats) or the manipulation of common bile duct without ligation (control rats). Six weeks after surgery, control and BDL rats underwent open-field, plus-maze and foot-fault behavioral tasks. The BDL rats developed chronic liver failure and exhibited a decrease in total distance traveled, increased total immobility time, smaller number of rearings, longer periods in the home base area and decreased percentage of time in the center zone of the arena, when compared to the control rats. Moreover, the performance of the BDL rats was not different from the control rats for the elevated plus-maze and foot-fault tasks. Therefore, the BDL rats demonstrated disturbed spontaneous locomotor and exploratory activities as a consequence of altered spatio-temporal organization of behavior.
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Affiliation(s)
- Renata Leke
- Department of Biochemistry, ICBS, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sol, Brazil.
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20
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Wilkinson DJ, Smeeton NJ, Castle PC, Watt PW. Absence of neuropsychological impairment in hyperammonaemia in healthy young adults; possible synergism in development of hepatic encephalopathy (HE) symptoms? Metab Brain Dis 2011; 26:203-12. [PMID: 21773808 DOI: 10.1007/s11011-011-9251-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Accepted: 07/04/2011] [Indexed: 12/16/2022]
Abstract
The aetiology of minimal hepatic encephalopathy (mHE) remains unclear. It is generally accepted that hyperammonaemia plays a major role, however there are a multitude of metabolic perturbations present. To determine the contribution of hyperammonaemia to mHE symptom development, ten healthy males (Age:25 ± 5 yrs, BM:76.3 ± 7.1 kg, Height:178.6 ± 4.5 cm, mean ± SD) received two 4 h intravenous infusions of either a 2% ammonium chloride solution (AMM) or a placebo (PLA;0.9% sodium chloride) using a double blind cross-over design. Sensations of fatigue were measured at baseline, 2 and 4 h using the Multidimensional Fatigue Symptom Inventory-Short Form (MFSI-SF) questionnaire. Learning & memory, motor control and cognition were assessed using Rey's Auditory Verbal Learning Test (AVL), Continuous Compensatory Tracking (COMPTRACK) Task and Inhibitory Control Test (ICT) respectively. Arterialised venous blood samples were collected every hour, and analysed for ammonia concentration. There was a significantly higher plasma ammonia concentration in the AMM trial than the PLA trial at every time point during the infusion, peaking at 2 h (57 ± 4 μmol/L PLA, 225 ± 14 μmol/L AMM; p < 0.05). At 2 h there were significantly higher sensations of general fatigue (Z = -2.527, p = 0.008, 2 tailed) and physical fatigue (Z = -2.156, p = 0.027, 2 tailed), and lower sensations of vigour (Z = -2.456, p = 0.012, 2 tailed) for the AMM trial. There were no significant effects on the performance of the psychological tasks. These results demonstrate that hyperammonaemia in the absence of other complications induces significant sensations of fatigue but does not cause the typically observed performance impairment in individuals with mHE. Supporting the hypothesis for synergism between ammonia and other co-factors in mHE.
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Affiliation(s)
- Daniel J Wilkinson
- Department of Sport and Exercise Science, Chelsea School, University of Brighton, 30 Carlisle Road, Eastbourne BN20 7SN, UK.
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21
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Méndez M, Méndez-López M, López L, Aller MA, Arias J, Arias JL. Acetylcholinesterase activity in an experimental rat model of Type C hepatic encephalopathy. Acta Histochem 2011; 113:358-62. [PMID: 20138653 DOI: 10.1016/j.acthis.2010.01.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2009] [Revised: 01/15/2010] [Accepted: 01/18/2010] [Indexed: 01/15/2023]
Abstract
Patients with liver malfunction often suffer from hepatic encephalopathy, a neurological complication which can affect attention and cognition. Diverse experimental models have been used to study brain alterations that may be responsible for hepatic encephalopathy symptoms. The aim of the study was to determine whether cognitive impairment found in cirrhosis could be due to disturbance of acetylcholinesterase activity. Acetylcholinesterase activity was assessed in the brains of Wistar rats with thioacetamide-induced cirrhosis. The cirrhotic group displayed up-regulation of acetylcholinesterase levels in the entorrhinal cortex, anterodorsal and anteroventral thalamus and accumbens, whereas down-regulation was found in the CA1, CA3 and dentate gyrus of the hippocampus. Our results indicate that the experimental model of hepatic encephalopathy by chronic administration of thioacetamide presents alterations of acetylcholinesterase activity in brain limbic system regions, which play a role in attention and memory.
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Affiliation(s)
- Marta Méndez
- Laboratorio de Neurociencias, Departamento de Psicología, Universidad de Oviedo, Plaza Feijoo s/n, Oviedo, Spain.
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22
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Miranda ASD, Rodrigues DH, Vieira LB, Lima CX, Rachid MA, Vidigal PVT, Gomez MV, Reis HJD, Guatimosim C, Teixeira AL. A thioacetamide-induced hepatic encephalopathy model in C57BL/6 mice: a behavioral and neurochemical study. ARQUIVOS DE NEURO-PSIQUIATRIA 2011; 68:597-602. [PMID: 20730316 DOI: 10.1590/s0004-282x2010000400022] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Accepted: 04/07/2010] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Hepatic encephalopathy (HE) is a neuropsychiatric syndrome resulting from liver failure. In the present study, we aimed to standardize an animal model of HE induced by thioacetamide (TAA) in C57BL/6 mice evaluating behavioral symptoms in association with liver damage and alterations in neurotransmitter release. METHOD HE was induced by an intraperitoneal single dose of TAA (200 mg/kg, 600 mg/kg or 1,200 mg/kg). Behavioral symptoms were evaluated using the SHIRPA battery. Liver damage was confirmed by histopathological analysis. The glutamate release was measured using fluorimetric assay. RESULTS The neuropsychiatric state, motor behavior and reflex and sensory functions were significantly altered in the group receiving 600 mg/kg of TAA. Biochemical analysis revealed an increase in the glutamate release in the cerebral cortex of HE mice. CONCLUSION HE induced by 600 mg/kg TAA injection in C57BL/6 mice seems to be a suitable model to investigate the pathogenesis and clinical disorders of HE.
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Affiliation(s)
- Aline Silva de Miranda
- Laboratory of Immunopharmacology, Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
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23
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Méndez M, Méndez-López M, López L, Aller MA, Arias J, Arias JL. Portosystemic hepatic encephalopathy model shows reversal learning impairment and dysfunction of neural activity in the prefrontal cortex and regions involved in motivated behavior. J Clin Neurosci 2011; 18:690-4. [PMID: 21371891 DOI: 10.1016/j.jocn.2010.09.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Revised: 09/15/2010] [Accepted: 09/22/2010] [Indexed: 11/16/2022]
Abstract
Hepatic encephalopathy (HE) is a neurological complication that affects attention and memory. Experimental animal models have been used to study HE, the most frequent being the portacaval shunt (PCS). In order to investigate learning impairment and brain functional alterations in this model, we assessed reversal learning and neural metabolic activity in a PCS rat model. PCS and sham-operated rats were tested for reversal learning in the Morris water maze. Brains were then processed for cytochrome oxidase (CO) histochemistry. The PCS group had reversal learning impairment and a reduction in CO activity in the prefrontal cortex, ventral tegmental area and accumbens shell nucleus. These results suggest that this model of portosystemic HE shows learning impairments that could be linked to dysfunction in neural activity in the prefrontal cortex and regions involved in motivated behavior.
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Affiliation(s)
- M Méndez
- Laboratorio de Neurociencias, Departamento de Psicología, Universidad de Oviedo, Plaza Feijoo s/n. 33003, Oviedo, Spain.
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24
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Nagaoka MR, Le Sueur-Maluf L, Aguiar O, Castro GM, Spadari-Bratfisch RC, Ribeiro DA. Differential response related to genotoxicity in multiple organs of cirrhotic rats. Hepatol Int 2011; 5:740-6. [PMID: 21484143 DOI: 10.1007/s12072-010-9239-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Accepted: 12/16/2010] [Indexed: 01/27/2023]
Abstract
PURPOSE The aim of this study was to use the single cell gel (comet) assay to investigate whether blood, liver, heart, kidney, and brain are particularly sensitive organs for DNA damage in cirrhotic rats to predict genetic instability induced by cirrhosis. METHODS A total of 16 male Wistar rats (negative control, n = 8; experimental, n = 8) were submitted to bile duct ligation during 28 days. RESULTS Cirrhosis was able to induce genetic damage in liver and brain cells, as depicted by the mean tail moment. No genetic damage was induced in blood, heart, or kidney cells (i.e., no significant statistically differences were noticed when compared with negative control). CONCLUSIONS In conclusion, our results suggest that cirrhosis could contribute to DNA damage in liver and brain cells.
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Affiliation(s)
- Marcia R Nagaoka
- Departamento de Biociências, Universidade Federal de Sao Paulo, UNIFESP, Santos, SP, Brazil
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25
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Abstract
Hepatic encephalopathy is a serious complication of acute and chronic liver diseases and has a high mortality rate. The pathogenesis of hepatic encephalopathy remains unclear, and there is no means of prevention or effective cure for the disease. Therefore, there is an urgent need for the basic and clinical research of hepatic encephalopathy to elucidate its pathogenesis. The development of animal models is important for elucidating the pathogenesis of hepatic encephalopathy and providing new avenues for diagnosis and therapy of the disease. Among a variety of animal models, rat model is applied most widely for similarity to humans, repeatability, reliability, applicability, controllability, simplicity and economy. In this paper, we briefly review various rat models of hepatic encephalopathy that have different origins.
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Montoliu C, Rodrigo R, Monfort P, Llansola M, Cauli O, Boix J, Elmlili N, Agusti A, Felipo V. Cyclic GMP pathways in hepatic encephalopathy. Neurological and therapeutic implications. Metab Brain Dis 2010; 25:39-48. [PMID: 20195723 DOI: 10.1007/s11011-010-9184-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Accepted: 08/20/2009] [Indexed: 01/16/2023]
Abstract
Cyclic GMP (cGMP) modulates important cerebral processes including some forms of learning and memory. cGMP pathways are strongly altered in hyperammonemia and hepatic encephalopathy (HE). Patients with liver cirrhosis show reduced intracellular cGMP in lymphocytes, increased cGMP in plasma and increased activation of soluble guanylate cyclase by nitric oxide (NO) in lymphocytes, which correlates with minimal HE assessed by psychometric tests. Activation of soluble guanylate cyclase by NO is also increased in cerebral cortex, but reduced in cerebellum, from patients who died with HE. This opposite alteration is reproduced in vivo in rats with chronic hyperammonemia or HE. A main pathway modulating cGMP levels in brain is the glutamate-NO-cGMP pathway. The function of this pathway is impaired both in cerebellum and cortex of rats with hyperammonemia or HE. Impairment of this pathway is responsible for reduced ability to learn some types of tasks. Restoring the pathway and cGMP levels in brain restores learning ability. This may be achieved by administering phosphodiesterase inhibitors (zaprinast, sildenafil), cGMP, anti-inflammatories (ibuprofen) or antagonists of GABAA receptors (bicuculline). These data support that increasing cGMP by safe pharmacological means may be a new therapeutic approach to improve cognitive function in patients with minimal or clinical HE.
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Affiliation(s)
- Carmina Montoliu
- Fundación Investigación Hospital Clínico de Valencia, Valencia, Spain
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27
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Wilkinson DJ, Smeeton NJ, Watt PW. Ammonia metabolism, the brain and fatigue; revisiting the link. Prog Neurobiol 2010; 91:200-19. [PMID: 20138956 DOI: 10.1016/j.pneurobio.2010.01.012] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Revised: 01/27/2010] [Accepted: 01/29/2010] [Indexed: 12/15/2022]
Abstract
This review addresses the ammonia fatigue theory in light of new evidence from exercise and disease studies and aims to provide a view of the role of ammonia during exercise. Hyperammonemia is a condition common to pathological liver disorders and intense or exhausting exercise. In pathology, hyperammonemia is linked to impairment of normal brain function and the onset of the neurological condition, hepatic encephalopathy. Elevated blood ammonia concentrations arise due to a diminished capacity for removal via the liver and lead to increased exposure of organs, such as the brain, to the toxic effects of ammonia. High levels of brain ammonia can lead to deleterious alterations in astrocyte morphology, cerebral energy metabolism and neurotransmission, which may in turn impact on the functioning of important signalling pathways within the neuron. Such changes are believed to contribute to the disturbances in neuropsychological function, in particular the learning, memory, and motor control deficits observed in animal models of liver disease and also patients with cirrhosis. Hyperammonemia in exercise occurs as a result of an increased production by contracting muscle, through adenosine monophosphate (AMP) deamination (the purine nucleotide cycle) and branched chain amino acid (BCAA) deamination prior to oxidation. Plasma concentrations of ammonia during exercise often achieve or exceed those measured in liver disease patients, resulting in increased cerebral uptake. In this article we propose that exercise-induced hyperammonemia may lead to concomitant disturbances in brain function, potentially through similar mechanisms underpinning pathology, which may impact on performance as fatigue or reduced function, especially during extreme exercise.
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Affiliation(s)
- Daniel J Wilkinson
- Department of Sport and Exercise Science, Chelsea School, University of Brighton, 30 Carlisle Road, Eastbourne, UK.
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28
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Monfort P, Cauli O, Montoliu C, Rodrigo R, Llansola M, Piedrafita B, El Mlili N, Boix J, Agustí A, Felipo V. Mechanisms of cognitive alterations in hyperammonemia and hepatic encephalopathy: therapeutical implications. Neurochem Int 2009; 55:106-12. [PMID: 19428813 DOI: 10.1016/j.neuint.2009.01.021] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Revised: 01/14/2009] [Accepted: 01/19/2009] [Indexed: 01/06/2023]
Abstract
Patients with liver diseases (e.g. cirrhosis) may present hepatic encephalopathy (HE), an alteration in cerebral function which is a consequence of previous failure of liver function. Patients with minimal or clinical HE present different levels of cognitive impairment. Hyperammonemia is considered a main contributor to the neurological alterations in HE. Animal models of chronic HE (e.g. rats with portacaval shunts) or of "pure" hyperammonemia also show impaired cognitive function. The studies summarized here show that the impairment of some types of cognitive function in chronic HE is due to the impaired function of the glutamate-nitric oxide-cGMP pathway in brain. Both hyperammonemia and neuroinflammation contribute to the impairment of the pathway and of cognitive function. Treatment of rats with chronic HE or hyperammonemia with inhibitors of phosphodiesterase 5 restores the function of the glutamate-nitric oxide-cGMP pathway and cGMP levels in brain as well as the ability to learn a Y maze conditional discrimination task. The same beneficial effects may be obtained by treating the rats chronically with an anti-inflammatory, ibuprofen. As the function of this pathway is also altered in brain of patients died in HE, this alteration would also contribute to cognitive impairment in patients with HE. Increasing cGMP by using inhibitors of phosphodiesterase 5 (PDE-5) or anti-inflammatories (under safe conditions) would be therefore a new therapeutic approach to improve learning and memory performance in individuals with minimal or clinical HE.
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Affiliation(s)
- Pilar Monfort
- Laboratory of Neurobiology, Centro de Investigacion Principe Felipe, Valencia, Spain
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