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Kumar JI, Wasserman J, Heller RS, Agazzi S. Spontaneous resolution of cerebral arteriovenous malformation after liver transplant: illustrative case. Br J Neurosurg 2021:1-4. [PMID: 34933609 DOI: 10.1080/02688697.2021.2016621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 09/25/2021] [Accepted: 12/05/2021] [Indexed: 01/02/2023]
Abstract
BACKGROUND Cerebral arteriovenous malformations (AVMs) have historically been considered congenital lesions with treatment options including surgery, radiation therapy, and observation. Spontaneous resolution of cerebral AVMs remains an exceedingly rare event with poorly understood pathophysiology. MATERIALS AND METHODS Herein we report a retrospective case review of a 28-year-old man with alcoholic cirrhosis who presented with a seizure 3 weeks after liver transplantation. Neuroimaging confirmed the presence of a Spetzler-Martin grade 2 AVM in the right frontal lobe. Due to the recent liver transplantation, treatment was deferred at the time of initial diagnosis and the patient was observed for a course of 1 year. Follow-up imaging 1 year later showed resolution of the AVM, confirmed by a catheter angiogram. CONCLUSION Spontaneous resolution of cerebral AVMs is a rare event. Treatment of chronic liver disease resulted in the normalization of angiogenic factors that likely led to AVM resolution. This case provides valuable insight into the vital role of angiogenesis in the natural history of AVMs.
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Affiliation(s)
- Jay I Kumar
- Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL, USA
| | - Jacob Wasserman
- Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL, USA
| | - Robert S Heller
- Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL, USA
- Department of Neurosurgery, Albany Medical Center, Albany, NY, USA
| | - Siviero Agazzi
- Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL, USA
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Dehghani M, Kunz N, Lei H. Diffusion behavior of cerebral metabolites of congenital portal systemic shunt mice assessed noninvasively by diffusion-weighted 1 H magnetic resonance spectroscopy. NMR IN BIOMEDICINE 2020; 33:e4198. [PMID: 31765073 DOI: 10.1002/nbm.4198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 08/27/2019] [Accepted: 09/13/2019] [Indexed: 06/10/2023]
Abstract
Diffusion-weighted 1 H-MRS (DW-MRS) allows for noninvasive investigation of the cellular compartmentalization of cerebral metabolites. DW-MRS applied to the congenital portal systemic shunt (PSS) mouse brain may provide specific insight into alterations of cellular restrictions associated with PSS in humans. At 14.1 T, adult male PSS and their age-matched healthy (Ctrl) mice were studied using DW-MRS covering b-values ranging from 0 to 45 ms/μm2 to determine the diffusion behavior of abundant metabolites. The remarkable sensitivity and spectral resolution, in combination with very high diffusion weighting, allowed for precise measurement of the diffusion properties of endogenous N-acetyl-aspartate, total creatine, myo-inositol, total choline with extension to glutamine and glutamate in mouse brains, in vivo. Most metabolites had comparable diffusion properties in PSS and Ctrl mice, suggesting that intracellular distribution space for these metabolites was not affected in the model. The slightly different diffusivity of the slow decaying component of taurine (0.015 ± 0.003 μm2 /ms in PSS vs 0.021 ± 0.002 μm2 /ms in Ctrl, P < 0.05) might support a cellular redistribution of taurine in the PSS mouse brain.
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Affiliation(s)
- Masoumeh Dehghani
- Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Department of Psychiatry, McGill University, Montreal, Canada
| | - Nicolas Kunz
- Center for Biomedical Imaging (CIBM), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Hongxia Lei
- Center for Biomedical Imaging (CIBM), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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A discussion of new-onset extrapyramidal syndrome without tremor and neuroimaging signs of encephalopathy following hepatic cirrhosis. INTERDISCIPLINARY NEUROSURGERY 2019. [DOI: 10.1016/j.inat.2019.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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4
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New-onset extrapyramidal symptoms in hepatic cirrhosis without neuroimaging signs of encephalopathy. Rev Neurol (Paris) 2019; 175:407-409. [DOI: 10.1016/j.neurol.2018.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 10/02/2018] [Accepted: 10/09/2018] [Indexed: 11/13/2022]
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5
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Heidari R. Brain mitochondria as potential therapeutic targets for managing hepatic encephalopathy. Life Sci 2019; 218:65-80. [DOI: 10.1016/j.lfs.2018.12.030] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 12/08/2018] [Accepted: 12/16/2018] [Indexed: 02/07/2023]
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Suárez I, Bodega G, Rubio M, Fernández B. Reduced TH expression and α-synuclein accumulation contribute towards nigrostriatal dysfunction in experimental hepatic encephalopathy. Restor Neurol Neurosci 2017; 35:469-481. [PMID: 28984618 DOI: 10.3233/rnn-170728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE The present work examines α-synuclein expression in the nigrostriatal system of a rat chronic hepatic encephalopathy model induced by portacaval anastomosis (PCA). There is evidence that dopaminergic dysfunction in disease conditions is strongly associated with such expression. Possible relationships among dopaminergic neurons, astroglial cells and α-synuclein expression were sought. METHODS Brain tissue samples from rats at 1 and 6 months post-PCA, and controls, were analysed immunohistochemically using antibodies against tyrosine hydroxylase (TH), α-synuclein, glial fibrillary acidic protein (GFAP) and ubiquitin (Ub). RESULTS In the control rats, TH immunoreactivity was detected in the neuronal cell bodies and processes in the substantia nigra pars compacta (SNc). A dense TH-positive network of neurons was also seen in the striatum. In the PCA-exposed rats, however, a reduction in TH-positive neurons was seen at both 1 and 6 months in the SNc, as well as a reduction in TH-positive fibres in the striatum. This was coincident with the appearance of α-synuclein-immunoreactive neurons in the SNc; some of the TH-positive neurons also showed α-synuclein immunoreactivity. In addition, α-synuclein accumulation was seen in the SNc and striatum at both 1 and 6 months post-PCA, whereas α-synuclein was only mildly expressed in the nigrostriatal pathway of the controls. Astrogliosis was also seen following PCA, as revealed by increased GFAP expression from 1 month to 6 months post-PCA in both the SN and striatum. The astroglial activation level in the SN paralleled the reduced neuronal expression of TH throughout PCA exposure. CONCLUSION α-synuclein accumulation following PCA may induce dopaminergic dysfunction via the downregulation of TH, as well as astroglial activation.
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Affiliation(s)
- Isabel Suárez
- Departamento de Biomedicina y Biotecnología, Universidad de Alcalá, Madrid, Spain
| | - Guillermo Bodega
- Departamento de Biomedicina y Biotecnología, Universidad de Alcalá, Madrid, Spain
| | - Miguel Rubio
- Departamento de Biomedicina y Biotecnología, Universidad de Alcalá, Madrid, Spain
| | - Benjamín Fernández
- Departamento de Biología Celular, Universidad Complutense, Madrid, Spain
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Lanz B, Rackayova V, Braissant O, Cudalbu C. MRS studies of neuroenergetics and glutamate/glutamine exchange in rats: Extensions to hyperammonemic models. Anal Biochem 2017; 529:245-269. [DOI: 10.1016/j.ab.2016.11.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 11/16/2016] [Accepted: 11/30/2016] [Indexed: 01/27/2023]
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Bémeur C, Cudalbu C, Dam G, Thrane AS, Cooper AJL, Rose CF. Brain edema: a valid endpoint for measuring hepatic encephalopathy? Metab Brain Dis 2016; 31:1249-1258. [PMID: 27272740 DOI: 10.1007/s11011-016-9843-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 05/19/2016] [Indexed: 12/12/2022]
Abstract
Hepatic encephalopathy (HE) is a major complication of liver failure/disease which frequently develops during the progression of end-stage liver disease. This metabolic neuropsychiatric syndrome involves a spectrum of symptoms, including cognition impairment, attention deficits and motor dysfunction which eventually can progress to coma and death. Pathologically, HE is characterized by swelling of the astrocytes which consequently leads to brain edema, a common feature found in patients with acute liver failure (ALF) as well as in cirrhotic patients suffering from HE. The pathogenic factors involved in the onset of astrocyte swelling and brain edema in HE are unresolved. However, the role of astrocyte swelling/brain edema in the development of HE remains ambiguous and therefore measuring brain edema as an endpoint to evaluate HE is questioned. The following review will determine the effect of astrocyte swelling and brain edema on neurological function, discuss the various possible techniques to measure brain edema and lastly to propose a number of neurobehavioral tests to evaluate HE.
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Affiliation(s)
- Chantal Bémeur
- Département de nutrition, Université de Montréal, Montréal, Québec, Canada
- Hepato-Neuro Laboratory, CRCHUM, Université de Montréal, Montréal, Québec, Canada
| | - Cristina Cudalbu
- Centre d'Imagerie Biomédicale (CIBM), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Gitte Dam
- Department of Medicine V (Hepatology and Gastroenterology), Aarhus, Denmark
| | - Alexander S Thrane
- Department of Ophthalmology, Haukeland University Hospital, 5012, Bergen, Norway
- Division of Glial Disease and Therapeutics, Center for Translational Neuromedicine, Department of Neurosurgery, University of Rochester Medical Center, Rochester, New York, 14642, USA
| | - Arthur J L Cooper
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York, 10595, USA
| | - Christopher F Rose
- Hepato-Neuro Laboratory, CRCHUM, Université de Montréal, Montréal, Québec, Canada.
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Dhanda S, Sandhir R. Role of dopaminergic and serotonergic neurotransmitters in behavioral alterations observed in rodent model of hepatic encephalopathy. Behav Brain Res 2015; 286:222-35. [PMID: 25639545 DOI: 10.1016/j.bbr.2015.01.042] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 01/17/2015] [Accepted: 01/22/2015] [Indexed: 02/06/2023]
Abstract
The present study was designed to evaluate the role of biogenic amines in behavioral alterations observed in rat model of hepatic encephalopathy (HE) following bile duct ligation (BDL). Male Wistar rats subjected to BDL developed biliary fibrosis after four weeks which was supported by altered liver function tests, increased ammonia levels and histological staining (Sirius red). Animals were assessed for their behavioral performance in terms of cognitive, anxiety and motor functions. The levels of dopamine (DA), serotonin (5-HT), epinephrine and norepinephrine (NE) were estimated in different regions of brain viz. cortex, hippocampus, striatum and cerebellum using HPLC along with activity of monoamine oxidase (MAO). Cognitive assessment of BDL rats revealed a progressive decline in learning, memory formation, retrieval, exploration of novel environment and spontaneous locomotor activity along with decrease in 5-HT and NE levels. This was accompanied by an increase in MAO activity. Motor functions of BDL rats were also altered which were evident from decrease in the time spent on the rotating rod and higher foot faults assessed using narrow beam walk task. A global decrease was observed in the DA content along with an increase in MAO activity. Histopathological studies using hematoxylin-eosin (H&E) and cresyl violet exhibited marked neuronal degeneration, wherein neurons appeared more pyknotic, condensed and damaged. The results reveal that dopaminergic and serotonergic pathways are disturbed in chronic liver failure post-BDL which may be responsible for behavioral impairments observed in HE.
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Affiliation(s)
- Saurabh Dhanda
- Department of Biochemistry, Basic Medical Science Block, Panjab University, Chandigarh 160014, India
| | - Rajat Sandhir
- Department of Biochemistry, Basic Medical Science Block, Panjab University, Chandigarh 160014, India.
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Altered modular organization of functional connectivity networks in cirrhotic patients without overt hepatic encephalopathy. BIOMED RESEARCH INTERNATIONAL 2014; 2014:727452. [PMID: 25165713 PMCID: PMC4066720 DOI: 10.1155/2014/727452] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 04/06/2014] [Accepted: 04/10/2014] [Indexed: 01/16/2023]
Abstract
Minimal hepatic encephalopathy (MHE) is associated with changes in functional connectivity. To investigate the patterns of modular changes of the functional connectivity in the progression of MHE, resting-state functional magnetic resonance imaging was acquired in 24 MHE patients, 31 cirrhotic patients without minimal hepatic encephalopathy (non-HE), and 38 healthy controls. Newman's metric, the modularity Q value, was maximized and compared in three groups. Topological roles with the progression of MHE were illustrated by intra- and intermodular connectivity changes. Results showed that the Q value of MHE patients was significantly lower than that of controls (P < 0.01) rather than that of non-HE patients (P > 0.05), which was correlated with neuropsychological test scores rather than the ammonia level and Child-Pugh score. Less intrasubcortical connections and more isolated subcortical modules were found with the progression of MHE. The non-HE patients had the same numbers of connect nodes as controls and had more hubs compared with MHE patients and healthy controls. Our findings supported that both intra- and intermodular connectivity, especially those related to subcortical regions, were continuously impaired in cirrhotic patients. The adjustments of hubs and connector nodes in non-HE patients could be a compensation for the decreased modularity in their functional connectivity networks.
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Moon JH, Jun DW, Yum MK, Lee KN, Lee HL, Lee OY, Yoon BC, Choi HS, Hahm JS, Seol IJ, Oh JW, Kim CR. Prolonged N200 is the early neurophysiologic change in the patient with minimal hepatic encephalopathy. Scand J Gastroenterol 2014; 49:604-10. [PMID: 24646220 DOI: 10.3109/00365521.2013.878382] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND In neurophysiological studies, P300, is well known for reflecting early cognitive impairment in minimal hepatic encephalopathy (MHE). Although P300 is investigated extensively, other early event-related potential (ERP) parameters have not been studied in MHE. METHODS The subjects were 21 adult cirrhotic patients without clinical encephalopathy and 29 normal controls. For neuropsychological testing, number connection tests, A and B (NCT-A, NCT-B), the line tracing test, the serial dotting test (SDT), and the digit symbol test (DST) were performed. For ERP testing, auditory oddball paradigms were used. The N100, P200, N200, and P300 parameters were measured. RESULTS Cirrhosis had longer neuropsychological performance scores on NCT-A, SDT, and DST than the control group. In neurophysiological test, cirrhotic patients showed longer latencies for N100, P200, N200, and P300 than the control group. Although P300 alteration was not seen in patients without MHE compared to the control group (325.4±43.3 vs. 345.21±35.1, p=0.25), N200 latency was significantly prolonged in cirrhotic patients without MHE compared to the healthy group (242.1±30.3 vs. 259.58±33.3, p=0.006). N200 also showed good correlation with psychometric hepatic encephalopathy score and critical flicker frequency. CONCLUSIONS N200 is a useful tool for assessing early changes of cognitive dysfunction in cirrhosis. It suggests that slower auditory cortical processing is the first sign of cerebral deterioration in patients with hepatic encephalopathy.
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Affiliation(s)
- Jin-Hwa Moon
- Department of Pediatrics, Hanyang University School of Medicine , Seoul , Korea
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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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The C57BL/6J mouse exhibits sporadic congenital portosystemic shunts. PLoS One 2013; 8:e69782. [PMID: 23936100 PMCID: PMC3720623 DOI: 10.1371/journal.pone.0069782] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 06/12/2013] [Indexed: 01/27/2023] Open
Abstract
C57BL/6 mice are the most widely used strain of laboratory mice. Using in vivo proton Magnetic Resonance Spectroscopy (1H MRS), we have repeatedly observed an abnormal neurochemical profile in the brains of both wild-type and genetically modified mice derived from the C57BL/6J strain, consisting of a several fold increase in cerebral glutamine and two fold decrease in myo-inositol. This strikingly abnormal neurochemical “phenotype” resembles that observed in chronic liver disease or portosystemic shunting and appeared to be independent of transgene, origin or chow and was not associated with liver failure. As many as 25% of animals displayed the abnormal neurochemical profile, questioning the reliability of this model for neurobiology. We conducted an independent study to determine if this neurochemical profile was associated with portosystemic shunting. Our results showed that 100% of the mice with high brain glutamine displayed portosystemic shunting by concomitant portal angiography while all mice with normal brain glutamine did not. Since portosystemic shunting is known to cause alterations in gene expression in many organs including the brain, we conclude that portosystemic shunting may be the most significant problem associated with C57BL/6J inbreeding both for its effect on the central nervous system and for its systemic repercussions.
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Braissant O, McLin VA, Cudalbu C. Ammonia toxicity to the brain. J Inherit Metab Dis 2013; 36:595-612. [PMID: 23109059 DOI: 10.1007/s10545-012-9546-2] [Citation(s) in RCA: 181] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Revised: 09/19/2012] [Accepted: 09/25/2012] [Indexed: 12/21/2022]
Abstract
Hyperammonemia can be caused by various acquired or inherited disorders such as urea cycle defects. The brain is much more susceptible to the deleterious effects of ammonium in childhood than in adulthood. Hyperammonemia provokes irreversible damage to the developing central nervous system: cortical atrophy, ventricular enlargement and demyelination lead to cognitive impairment, seizures and cerebral palsy. The mechanisms leading to these severe brain lesions are still not well understood, but recent studies show that ammonium exposure alters several amino acid pathways and neurotransmitter systems, cerebral energy metabolism, nitric oxide synthesis, oxidative stress and signal transduction pathways. All in all, at the cellular level, these are associated with alterations in neuronal differentiation and patterns of cell death. Recent advances in imaging techniques are increasing our understanding of these processes through detailed in vivo longitudinal analysis of neurobiochemical changes associated with hyperammonemia. Further, several potential neuroprotective strategies have been put forward recently, including the use of NMDA receptor antagonists, nitric oxide inhibitors, creatine, acetyl-L-carnitine, CNTF or inhibitors of MAPKs and glutamine synthetase. Magnetic resonance imaging and spectroscopy will ultimately be a powerful tool to measure the effects of these neuroprotective approaches.
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Affiliation(s)
- Olivier Braissant
- Service of Biomedicine, Lausanne University Hospital, Avenue Pierre-Decker 2, CI 02/33, CH-1011 Lausanne, Switzerland.
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Cudalbu C. In vivo studies of brain metabolism in animal models of Hepatic Encephalopathy using ¹H Magnetic Resonance Spectroscopy. Metab Brain Dis 2013; 28:167-74. [PMID: 23254563 DOI: 10.1007/s11011-012-9368-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 11/26/2012] [Indexed: 10/27/2022]
Abstract
Hepatic encephalopathy (HE) is a common and severe neuropsychiatric complication present in acute and chronic liver disease. The unique advantages of high field (1)H MRS provide a method for assessing pathogenic mechanism, diagnosis and monitoring of HE, as well as for treatment assessment or recovery after liver transplantation, in a reproducible and reliable non-invasive way. The purpose of the present review is to present some new features of in vivo proton Magnetic Resonance Spectroscopy ((1)H MRS) at high magnetic fields combined with some basic requirements for reliable metabolic profiling. Finally, in vivo applications of (1)H MRS in different HE animal models are presented.
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Affiliation(s)
- Cristina Cudalbu
- Ecole Polytechnique Fédérale de Lausanne, Laboratory for Functional and Metabolic Imaging, Station 6, CH F1 602 (Bâtiment CH), 1015 Lausanne, Switzerland.
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Cirrhosis-related Parkinsonism: prevalence, mechanisms and response to treatments. J Hepatol 2013; 58:698-705. [PMID: 23220368 DOI: 10.1016/j.jhep.2012.11.043] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 11/22/2012] [Accepted: 11/24/2012] [Indexed: 12/15/2022]
Abstract
BACKGROUND & AIMS Extrapyramidal and cerebellar symptoms belong to the most prominent features of episodic hepatic encephalopathy, and usually decrease upon ammonia-lowering therapy. Rapidly progressing parkinsonian symptoms, which are unresponsive to treatment of hepatic encephalopathy, indicate cirrhosis-related Parkinsonism. This study aims at analyzing the prevalence of cirrhosis-related Parkinsonism in patients with liver cirrhosis, and to study the functional status of the striatal dopaminergic system in these patients. METHODS 214 patients with liver cirrhosis who were consecutively seen at the out-patient clinic for liver transplant candidates and/or at the transplantation wards at Hannover Medical School, between August 1, 2008 and March 31, 2011, underwent a standardized neurological examination while on the waiting list or immediately after liver transplantation. Single photon emission computer tomography (SPECT) using (123)I-beta-CIT, for the evaluation of the striatal dopamine transporter function, and (123)I-IBZM for the evaluation of the striatal dopamine D2 receptor availability, was performed in 6 patients with cirrhosis-related Parkinsonism. RESULTS Cirrhosis-related Parkinsonism was diagnosed in 9 of 214 patients (4.2%). SPECT revealed significantly decreased dopamine receptor availability in 5 of 6 patients studied, and significantly decreased dopamine transporter availability in 3. Levodopa improved motor dysfunction in two of four patients treated, although only temporarily. Incomplete recovery was observed in two patients after liver transplantation. CONCLUSIONS Cirrhosis-related Parkinsonism is more frequent than presumed. The presented data suggest pre- and postsynaptic alteration of striatal dopaminergic neurotransmission as a possible cause of cirrhosis-related Parkinsonism and reveal the limited effects of dopaminergic therapy.
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Altered effective connectivity network of the basal ganglia in low-grade hepatic encephalopathy: a resting-state fMRI study with Granger causality analysis. PLoS One 2013; 8:e53677. [PMID: 23326484 PMCID: PMC3543360 DOI: 10.1371/journal.pone.0053677] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2012] [Accepted: 12/03/2012] [Indexed: 12/30/2022] Open
Abstract
Background The basal ganglia often show abnormal metabolism and intracranial hemodynamics in cirrhotic patients with hepatic encephalopathy (HE). Little is known about how the basal ganglia affect other brain system and is affected by other brain regions in HE. The purpose of this study was to investigate whether the effective connectivity network associated with the basal ganglia is disturbed in HE patients by using resting-state functional magnetic resonance imaging (rs-fMRI). Methodology/Principal Findings Thirty five low-grade HE patients and thirty five age- and gender- matched healthy controls participated in the rs-fMRI scans. The effective connectivity networks associated with the globus pallidus, the primarily affected region within basal ganglia in HE, were characterized by using the Granger causality analysis and compared between HE patients and healthy controls. Pearson correlation analysis was performed between the abnormal effective connectivity and venous blood ammonia levels and neuropsychological performances of all HE patients. Compared with the healthy controls, patients with low-grade HE demonstrated mutually decreased influence between the globus pallidus and the anterior cingulate cortex (ACC), cuneus, bi-directionally increased influence between the globus pallidus and the precuneus, and either decreased or increased influence from and to the globus pallidus in many other frontal, temporal, parietal gyri, and cerebellum. Pearson correlation analyses revealed that the blood ammonia levels in HE patients negatively correlated with effective connectivity from the globus pallidus to ACC, and positively correlated with that from the globus pallidus to precuneus; and the number connectivity test scores in patients negatively correlated with the effective connectivity from the globus pallidus to ACC, and from superior frontal gyrus to globus pallidus. Conclusions/Significance Low-grade HE patients had disrupted effective connectivity network of basal ganglia. Our findings may help to understand the neurophysiological mechanisms underlying the HE.
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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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Li T, Li X, Zhou W, Cui X, Ma L. Dynamic susceptibility contrast-enhanced first-pass perfusion MR imaging in patients with subclinical hepatic encephalopathy. J Neuroradiol 2011; 39:290-4. [PMID: 22047891 DOI: 10.1016/j.neurad.2011.09.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2011] [Revised: 08/30/2011] [Accepted: 09/12/2011] [Indexed: 12/30/2022]
Abstract
BACKGROUND AND PURPOSE Subclinical hepatic encephalopathy (SHE) is frequently reported on single-photon emission computed tomography (SPECT), but is rarely described with magnetic resonance (MR) techniques. This study aimed to investigate hemodynamic changes in brain basal ganglia in patients with SHE using dynamic susceptibility contrast (DSC)-enhanced MR perfusion imaging. METHODS Twelve patients with SHE and ten age- and education-matched volunteers agreed to undergo MR examination. The scanning protocol included conventional anatomical images and DSC-enhanced perfusion MR imaging. Using MGH perfusion software, parameter maps of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) were created. The bilateral caudate nucleus head, globus pallidus, putamen and thalamus were selected as regions of interest (ROI), with ipsilateral white matter of the frontal lobe used as reference. Ratios (ROI versus ipsilateral white matter in frontal lobe) for CBF, CBV and MTT in the patient group were compared with those in the control group. RESULTS The CBF ratios for every ROI were higher in SHE patients versus the controls. Statistically, significant increases were detected in the left globus pallidus, putamen and thalamus (P<0.05). For MTT, the reduction in values reached statistical significance in the right head of the caudate nucleus and bilateral thalamus (P<0.05). CBV values were not significantly different compared with those of the control group (P>0.05). CONCLUSION Increased CBF and decreased MTT values in the basal ganglia and thalamus were identified in patients with SHE. The CBF increase was compatible with the idea that the CBF is redistributed from cortical areas to the basal ganglia structures.
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Affiliation(s)
- Tao Li
- Department of Radiology, The General Hospital of Chinese People's Armed Police Forces, No 69, Yongding Road, 100039 Beijing, China
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Tryc AB, Alwan G, Bokemeyer M, Goldbecker A, Hecker H, Haubitz M, Weissenborn K. Cerebral metabolic alterations and cognitive dysfunction in chronic kidney disease. Nephrol Dial Transplant 2011; 26:2635-41. [DOI: 10.1093/ndt/gfq729] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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21
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Tarnacka B, Szeszkowski W, Gołębiowski M, Członkowska A. Brain proton magnetic spectroscopy in long-term treatment of Wilson's disease patients. Metab Brain Dis 2010; 25:325-9. [PMID: 20838861 DOI: 10.1007/s11011-010-9214-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Accepted: 04/30/2010] [Indexed: 12/18/2022]
Abstract
We reported the brain proton magnetic resonance spectroscopy (MRS) findings in 27 Wilson's disease (WD) patients treated more than 6 years in neurological (nWD) and hepatic (hWD) subgroups. We investigated four hWD patients, with no improvement and eight with marked improvement; and eight nWD patients with marked improvement and seven with no improvement of clinical status. In nWD patients with improvement the MRS showed significantly higher Cho/Cr, Glx/Cr ratios levels. In hWD patients with no improvement the lower Cho/Cr and in nWD significantly lower NAA/Cr and higher Cho/Cr and Lip/Cr ratios were detected. In nWD patients with improvement the spectroscopic pattern, can be related to gliosis. In patients with no neurological improvement a persistent neuronal dysfunction can occur, perhaps as a result of copper or iron deposition.
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Affiliation(s)
- Beata Tarnacka
- II Department of Neurology, Institute of Psychiatry and Neurology, 9 Sobieskiego Str., Warsaw, Poland.
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22
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Butz M, Timmermann L, Braun M, Groiss SJ, Wojtecki L, Ostrowski S, Krause H, Pollok B, Gross J, Südmeyer M, Kircheis G, Häussinger D, Schnitzler A. Motor impairment in liver cirrhosis without and with minimal hepatic encephalopathy. Acta Neurol Scand 2010; 122:27-35. [PMID: 20003084 DOI: 10.1111/j.1600-0404.2009.01246.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
AIM Manifest hepatic encephalopathy (HE) goes along with motor symptoms such as ataxia, mini-asterixis, and asterixis. The relevance of motor impairments in cirrhotics without and with minimal HE (mHE) is still a matter of debate. PATIENTS AND METHODS We tested three different groups of patients with liver cirrhosis: no signs of HE (HE 0), mHE, and manifest HE grade 1 according to the West Haven criteria (HE 1). All patients (n = 24) and 11 healthy control subjects were neuropsychometrically tested including critical flicker frequency (CFF), a reliable measure for HE. Motor abilities were assessed using Fahn Tremor Scale and International Ataxia Rating Scale. Fastest alternating index finger movements were analyzed for frequency and amplitude. RESULTS Statistical analyses showed an effect of HE grade on tremor and ataxia (P < 0.01). Additionally, both ratings yielded strong negative correlation with CFF (P < 0.01, R = -0.5). Analysis of finger movements revealed an effect of HE grade on movement frequency (P < 0.03). Moreover, decreasing movement frequency and increasing movement amplitude parallel decreasing CFF (P < 0.01, R = 0.6). CONCLUSION Our results indicate that ataxia, tremor, and slowing of finger movements are early markers for cerebral dysfunction in HE patients even prior to neuropsychometric alterations becoming detectable.
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Suárez I, Bodega G, Rubio M, Fernández B. Induction of NOS and nitrotyrosine expression in the rat striatum following experimental hepatic encephalopathy. Metab Brain Dis 2009; 24:395-408. [PMID: 19763802 DOI: 10.1007/s11011-009-9154-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2009] [Accepted: 04/20/2009] [Indexed: 11/24/2022]
Abstract
Hepatic encephalopathy (HE) is a neurologic disease associated with hepatic dysfunction. Astroglial and neuronal alterations have been described in the basal ganglia in HE. Our study was performed to determine whether such alterations are mediated by nitric oxide (NO), by using an experimental model of HE (portacaval anastomosis [PCA]). The expression of the NO synthases (nNOS and iNOS) and the production of nitrotyrosine (NT) were evaluated in the striatum of rats exposed to PCA for 1 and 6 months. The expression of nNOS in the striatal neurons of PCA rats was increased compared to controls. nNOS expression was also detectable in astrocytes after 6 months of exposure to PCA. Whereas astroglial cells in the normal striatum showed no iNOS expression, iNOS was expressed in the astrocytes of PCA brains, mainly in perivascular processes at 6 months PCA exposure (demonstrated by colocalization with GFAP). The increased expression of both the nNOS and iNOS isoforms in PCA rats might indicate a critical role for NO in the pathomechanism of HE. To study the potential cell damage caused by NO, the deposition of NT in PCA-rats was analysed. Nitrotyrosine was detected in neurons although it was mainly seen in the astrocytes of PCA brains, in which double immunolabelling showed NT to be colocalized with GFAP. Thus, the present study shows the induction of iNOS and NT in astrocytes, which increases with the duration of PCA exposure. This suggests that the induced astroglial production of NO during PCA might be one of the main factors contributing to HE.
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Affiliation(s)
- Isabel Suárez
- Departamento de Biología Celular y Genética, Facultad de Biología, Universidad de Alcalá, 28871 Madrid, Spain.
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Long LL, Li XR, Huang ZK, Jiang YM, Fu SX, Zheng W. Relationship between changes in brain MRI and (1)H-MRS, severity of chronic liver damage, and recovery after liver transplantation. Exp Biol Med (Maywood) 2009; 234:1075-85. [PMID: 19546351 DOI: 10.3181/0903-rm-118] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Magnetic resonance imaging (MRI) and (1)H magnetic resonance spectroscopy ((1)H-MRS) have been used in clinics for diagnosis of chronic liver diseases. This study was designed to investigate the relationship between MRI/MRS outcomes and the severity of liver damage. Of 50 patients examined, the MRI signal intensity in the globus pallidus as determined by pallidus index (PI) increased as the disease severity (scored by Child Pugh ranking) worsened (r = 0.353, P < 0.05). The changes in PI values were also linearly associated with Mn concentrations in whole blood (MnB) (r = 0.814, P < 0.01). MRS analysis of four major brain metabolites (i.e., Cho, mI, Glx, and NAA) revealed that the ratios of Cho/Cr and mI/Cr in cirrhosis and CHE patients were significantly decreased in comparison to controls (P < 0.05), whereas the ratio of Glx/Cr was significantly increased (P < 0.05). The Child Pugh scores significantly correlated with mI/Cr (-0.484, P < 0.01) and Glx (0.369, P < 0.05), as well as MnB (0.368, P < 0.05), but not with other brain metabolites. Three patients who received a liver transplant experienced normalization of brain metabolites within 3 months of post-transplantation; the MR imaging of Mn in the globus pallidus completely disappeared 5 months after the surgery. Taken together, this clinical study, which combined MRI/MRS analysis, autopsy exam and liver transplant, clearly demonstrates that liver injury-induced brain Mn accumulation can reversibly alter the homeostasis of brain metabolites Cho, mI and Glx. Our data further suggest that liver transplantation can restore normal brain Mn levels.
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Affiliation(s)
- Li-Ling Long
- Department of Radiology, the First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, China
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Shah NJ, Neeb H, Kircheis G, Engels P, Häussinger D, Zilles K. Quantitative cerebral water content mapping in hepatic encephalopathy. Neuroimage 2008; 41:706-17. [PMID: 18456518 DOI: 10.1016/j.neuroimage.2008.02.057] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2007] [Revised: 02/19/2008] [Accepted: 02/21/2008] [Indexed: 11/17/2022] Open
Abstract
There is increasing evidence that the pathophysiology of hepatic encephalopathy is tightly associated with low-grade cerebral oedema; however, no method has yet specifically and unambiguously confirmed this hypothesis in vivo. The current study describes the quantitative measurement of localised water content using MRI in a cohort of 38 patients suffering from hepatic encephalopathy. A significant global increase in cerebral water content was observed in white matter whereas water content in grey matter was globally unaffected. However, significant spatial variations in the water content distribution, especially in grey matter, were observed and were correlated with disease grade and critical flicker frequency. In addition, regions-of-interest were defined and a significant change in water content with disease grade was found in the frontal and occipital white matter, the globus pallidus, the anterior limb of the internal capsule and the putamen. No association of water content and HE grade was established for the occipital visual and frontal cortices, the thalamus, the posterior limb of the internal capsule, the caudate nucleus and the coronal white matter. In conclusion, the measurements presented here are the first direct and quantitative demonstration of the presence of low-grade cerebral oedema in patients with hepatic encephalopathy. Further, absolute changes in tissue water content were quantified for various brain regions.
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Affiliation(s)
- N J Shah
- Institute of Neuroscience and Biophysics 3 - Medicine, Research Centre Jülich GmbH, 52425 Jülich, Germany.
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Aschner M, Guilarte TR, Schneider JS, Zheng W. Manganese: recent advances in understanding its transport and neurotoxicity. Toxicol Appl Pharmacol 2007; 221:131-47. [PMID: 17466353 PMCID: PMC1950780 DOI: 10.1016/j.taap.2007.03.001] [Citation(s) in RCA: 415] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Revised: 01/16/2007] [Accepted: 03/02/2007] [Indexed: 11/19/2022]
Abstract
The present review is based on presentations from the meeting of the Society of Toxicology in San Diego, CA (March 2006). It addresses recent developments in the understanding of the transport of manganese (Mn) into the central nervous system (CNS), as well as brain imaging and neurocognitive studies in non-human primates aimed at improving our understanding of the mechanisms of Mn neurotoxicity. Finally, we discuss potential therapeutic modalities for treating Mn intoxication in humans.
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Affiliation(s)
- Michael Aschner
- Department of Pediatrics, and The Kennedy Center for Research on Human Development, Vanderbilt University, School of Medicine, Nashville, TN 37232-2495, USA.
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27
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Jiang Y, Zheng W, Long L, Zhao W, Li X, Mo X, Lu J, Fu X, Li W, Liu S, Long Q, Huang J, Pira E. Brain magnetic resonance imaging and manganese concentrations in red blood cells of smelting workers: search for biomarkers of manganese exposure. Neurotoxicology 2006; 28:126-35. [PMID: 16978697 PMCID: PMC3983995 DOI: 10.1016/j.neuro.2006.08.005] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2006] [Revised: 08/10/2006] [Accepted: 08/14/2006] [Indexed: 10/24/2022]
Abstract
The MRI technique has been used in diagnosis of manganism in humans and non-human primates. This cross-sectional study was designed to explore whether the pallidal signal intensity in T1-weighted MRI correlated with Mn levels in the blood compartment among Mn-exposed workers and to understand to what extent the MRI signal could reflect Mn exposure. A group of 18 randomly selected male Mn-exposed workers of which 13 were smelting workers with high exposure (mean of airborne Mn in work place: 1.26 mg/m3; range: 0.31-2.93 mg/m3), and 5 power distribution control workers with low exposure (0.66 mg/m3 and 0.23-0.77 mg/m3) from a ferroalloy factory, and another group of 9 male subjects as controls from a non-smelting factory who were office or cafeteria workers (0.01 mg/m3 and 0-0.03 mg/m3) were recruited for neurological tests, MRI examination, and analysis of Mn in whole blood (MnB), plasma (MnP) or red blood cells (MnRBC). No clinical symptoms and signs of manganism were observed among these workers. MRI data showed average increases of 7.4% (p<0.05) and 16.1% (p<0.01) in pallidal index (PI) among low- and high-exposed workers, respectively, as compared to controls. Fourteen out of 18 Mn-exposed workers (78%) had intensified PI values, while this proportion was even higher (85%) among the high Mn-exposed workers. Among exposed workers, the PI values were significantly associated with MnRBC (r=0.55, p=0.02). Our data suggest that the workers exposed to airborne Mn, but without clinical symptoms, display an exposure-related, intensified MRI signal. The MRI, as well as MnRBC, may be useful in early diagnosis of Mn exposure.
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Affiliation(s)
- Yueming Jiang
- Department of Occupational Health and Toxicology, Guangxi Medical University, Nanning 530021, China
| | - Wei Zheng
- School of Health Sciences, Purdue University, 550 Stadium Mall Drive, CIVL-1163D, West Lafayette, IN 47907, USA
- Corresponding author. Tel.: +1 765 496 6447; fax: +1 765 496 1377. (W. Zheng)
| | - Liling Long
- Department of Radiology, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Weijia Zhao
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Xiangrong Li
- Department of Radiology, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Xuean Mo
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Jipei Lu
- Department of Occupational Health and Toxicology, Guangxi Medical University, Nanning 530021, China
| | - Xue Fu
- Department of Occupational Health and Toxicology, Guangxi Medical University, Nanning 530021, China
| | - Wenmei Li
- Department of Radiology, The First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Shouting Liu
- Guangxi Center for Analysis and Test Research, Nanning 530021, China
| | - Quanyong Long
- Worker’s Hospital of Guangxi Bayi Ferroalloy Company, Laibin 546102, China
| | - Jinli Huang
- Worker’s Hospital of Guangxi Bayi Ferroalloy Company, Laibin 546102, China
| | - Enrico Pira
- Department of Traumatology, Orthopaedics and Occupational Health, University of Turin, Turin 10126, Italy
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Pidoplichko VI, Dani JA. Acid-sensitive ionic channels in midbrain dopamine neurons are sensitive to ammonium, which may contribute to hyperammonemia damage. Proc Natl Acad Sci U S A 2006; 103:11376-80. [PMID: 16847263 PMCID: PMC1544094 DOI: 10.1073/pnas.0600768103] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Acid-sensitive ion channels (ASICs) are proton-gated and belong to the family of degenerin channels. In the mammalian nervous system, ASICs are most well known in sensory neurons, where they are involved in nociception, occurring when injury or inflammation causes acidification. ASICs also are widely expressed in the CNS, and some synaptic roles have been revealed. Because neuronal activity can produce pH changes, ASICs may respond to local acidic transients and alter the excitability of neuronal circuits more widely than is presently appreciated. Furthermore, ASICs have been found to underlie calcium transients that contribute to neuronal death. Degeneration of midbrain dopamine neurons is characteristic of advanced idiopathic Parkinson's disease. Therefore, we tested for functional ASICs in midbrain dopamine neurons of the ventral tegmental area and substantia nigra compacta. Patch-clamp electrophysiology applied to murine midbrain slices revealed abundant acid-sensitive channels. The ASICs were gated and desensitized by extracellular application of millimolar concentrations of NH(4)Cl. Although the NH(4)Cl solution contains micromolar concentrations of NH(3) at pH 7.4, our evidence indicates that NH(4)(+) gates the ASICs. The proton-gated and the ammonium-gated currents were inhibited by tarantula venom (psalmotoxin), which is specific for the ASIC1a subtype. The results show that acid-sensitive channels are expressed in midbrain dopamine neurons and suggest that ammonium sensitivity is a widely distributed ASIC characteristic in the CNS, including the hippocampus. The ammonium sensitivity suggests a role for ASIC1s in hepatic encephalopathy, cirrhosis, and other neuronal disorders that are associated with hyperammonemia.
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Affiliation(s)
- Volodymyr I. Pidoplichko
- Department of Neuroscience, Menninger Department of Psychiatry and Behavioral Science, and Program in Structural and Computational Biology and Molecular Biophysics, Baylor College of Medicine, Houston, TX 77030
| | - John A. Dani
- Department of Neuroscience, Menninger Department of Psychiatry and Behavioral Science, and Program in Structural and Computational Biology and Molecular Biophysics, Baylor College of Medicine, Houston, TX 77030
- *To whom correspondence should be addressed. E-mail:
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Binesh N, Huda A, Thomas MA, Wyckoff N, Bugbee M, Han S, Rasgon N, Davanzo P, Sayre J, Guze B, Martin P, Fawzy F. Hepatic encephalopathy: a neurochemical, neuroanatomical, and neuropsychological study. J Appl Clin Med Phys 2006; 7:86-96. [PMID: 16518320 PMCID: PMC5722484 DOI: 10.1120/jacmp.v7i1.2151] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Hepatic encephalopathy (HE) is normally diagnosed by neuropsychological (NP) tests, which are not very specific and do not reveal the underlying pathology. Magnetic resonance imaging (MRI) and spectroscopy (MRS) of the brain offer alternative and possibly more specific markers for HE. These methods were applied in conjunction with NP testing in order to determine their usefulness in the identification of HE and to understand the pathogenesis of HE more clearly. MR imaging and spectroscopy examinations, in addition to a battery of 15 NP tests, were administered to investigate 31 patients awaiting liver transplantation and 23 healthy controls. MR image intensities from the globus pallidus region were calculated and normalized to those of the thalamus. Absolute concentrations and ratios with respect to creatine (Cr) of several metabolites were computed from MR spectra. The MR data were correlated with the results of NP tests. The patients showed impairment in NP tests of attention and visuospatial and verbal fluency. In T1-weighted MRI, the relative intensity of the globus pallidus with respect to that of the thalamus region was significantly elevated in patients and correlated(negatively) with three NP tests (Hooper, FAS, and Trails B). The absolute concentrations of myo-inositol (mI) and choline (Ch) were significantly reduced in three brain regions. In addition, the absolute concentrations of glutamine (Gln) and combined glutamate and glutamine (Glx) were increased in all three locations, with Gln increase being significant in all areas while that of Glx only in the occipital white matter. In summary, this study partially confirms a hypothesized mechanism of HE pathogenesis, an increased synthesis of glutamine by brain glutamate in astrocytes due to excessive blood ammonia, followed by a compensatory loss of myo-inositol to maintain astrocyte volume homeostasis. It also indicates that the hyperintensity observed in globus pallidus could be used as complementary to the NP test scores in evaluating the mental health of HE patients.
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Affiliation(s)
- Nader Binesh
- Departments of Radiological SciencesUniversity of CaliforniaLos AngelesCalifornia90095
| | - Amir Huda
- Departments of Radiological SciencesUniversity of CaliforniaLos AngelesCalifornia90095
- Department of PhysicsCalifornia State UniversityFresnoCalifornia93740U.S.A.
| | - M. Albert Thomas
- Departments of Radiological SciencesUniversity of CaliforniaLos AngelesCalifornia90095
- Departments of PsychiatryUniversity of CaliforniaLos AngelesCalifornia90095
| | - Nathaniel Wyckoff
- Departments of Radiological SciencesUniversity of CaliforniaLos AngelesCalifornia90095
| | - Mary Bugbee
- Departments of Radiological SciencesUniversity of CaliforniaLos AngelesCalifornia90095
| | - Steven Han
- Departments of HepatologyUniversity of CaliforniaLos AngelesCalifornia90095
| | - Natalie Rasgon
- Departments of PsychiatryUniversity of CaliforniaLos AngelesCalifornia90095
| | - Pablo Davanzo
- Departments of PsychiatryUniversity of CaliforniaLos AngelesCalifornia90095
| | - James Sayre
- Departments of Radiological SciencesUniversity of CaliforniaLos AngelesCalifornia90095
| | - Barry Guze
- Departments of PsychiatryUniversity of CaliforniaLos AngelesCalifornia90095
| | - Paul Martin
- Departments of HepatologyUniversity of CaliforniaLos AngelesCalifornia90095
| | - Fawzy Fawzy
- Departments of PsychiatryUniversity of CaliforniaLos AngelesCalifornia90095
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Rovira A. Resonancia magnética craneal en la encefalopatía hepática. RADIOLOGIA 2005. [DOI: 10.1016/s0033-8338(05)72828-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Jover R, Compañy L, Gutiérrez A, Lorente M, Zapater P, Poveda MJ, Such J, Pascual S, Palazón JM, Carnicer F, Ferrandis F, Pérez-Mateo M. Clinical significance of extrapyramidal signs in patients with cirrhosis. J Hepatol 2005; 42:659-65. [PMID: 15826714 DOI: 10.1016/j.jhep.2004.12.030] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2004] [Revised: 11/25/2004] [Accepted: 12/01/2004] [Indexed: 12/15/2022]
Abstract
BACKGROUND/AIMS Extrapyramidal signs have been described in cirrhosis and there is little information about their clinical significance. The aims of this study have been to investigate the relationship between extrapyramidal signs and cognitive impairment, and what is their influence on quality of life. METHODS 46 patients with cirrhosis were evaluated for cognitive impairment with psychometric tests (Trail-Making Test part A, Grooved-Pegboard, Block-Design, Oral Symbol Digit and Stroop Test) and cognitive evoked potentials (P300). Extrapyramidal signs were evaluated using the UPDRS scale. Health-related quality of life (HRQL) was measured using SF-36 scale and the Chronic Liver Disease Questionnaire (CLDQ). RESULTS Twenty-two patients had extrapyramidal signs, and these patients scored worse in all psychometric tests, except Block-Design. Patients with extrapyramidal signs also showed a longer P300 latency. Moreover, patients with extrapyramidal signs had the worst score in all the HRQL scales used. A multivariate analysis disclosed that the only variable showing an independent relationship to the mental component summary of SF-36 and with CLDQ was UPDRS score. CONCLUSIONS We have found a clear relationship between the presence of extrapyramidal signs and cognitive impairment. Moreover, patients with extrapyramidal signs have worse scores in quality of life scales.
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Affiliation(s)
- Rodrigo Jover
- Department of Gastroenterology-Liver Unit, Hospital General Universitario de Alicante, C/Pintor Baeza, sn, E-03010 Alicante, Spain.
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Psychosocial, emotional, and neuropsychologic factors influencing compliance and liver transplantation outcomes. Curr Opin Organ Transplant 2004. [DOI: 10.1097/01.mot.0000127680.62641.34] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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