1
|
Gordji-Nejad A, Matusch A, Kleedörfer S, Jayeshkumar Patel H, Drzezga A, Elmenhorst D, Binkofski F, Bauer A. Single dose creatine improves cognitive performance and induces changes in cerebral high energy phosphates during sleep deprivation. Sci Rep 2024; 14:4937. [PMID: 38418482 PMCID: PMC10902318 DOI: 10.1038/s41598-024-54249-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/10/2024] [Indexed: 03/01/2024] Open
Abstract
The inverse effects of creatine supplementation and sleep deprivation on high energy phosphates, neural creatine, and cognitive performances suggest that creatine is a suitable candidate for reducing the negative effects of sleep deprivation. With this, the main obstacle is the limited exogenous uptake by the central nervous system (CNS), making creatine only effective over a long-term diet of weeks. Thus far, only repeated dosing of creatine over weeks has been studied, yielding detectable changes in CNS levels. Based on the hypothesis that a high extracellular creatine availability and increased intracellular energy consumption will temporarily increase the central creatine uptake, subjects were orally administered a high single dose of creatinemonohydrate (0.35 g/kg) while performing cognitive tests during sleep deprivation. Two consecutive 31P-MRS scans, 1H-MRS, and cognitive tests were performed each at evening baseline, 3, 5.5, and 7.5 h after single dose creatine (0.35 g/kg) or placebo during sub-total 21 h sleep deprivation (SD). Our results show that creatine induces changes in PCr/Pi, ATP, tCr/tNAA, prevents a drop in pH level, and improves cognitive performance and processing speed. These outcomes suggest that a high single dose of creatine can partially reverse metabolic alterations and fatigue-related cognitive deterioration.
Collapse
Affiliation(s)
- Ali Gordji-Nejad
- Institute of Neuroscience and Medicine (INM-2), Molecular Organization of the Brain, Forschungszentrum Jülich, 52425, Jülich, Germany.
| | - Andreas Matusch
- Institute of Neuroscience and Medicine (INM-2), Molecular Organization of the Brain, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Sophie Kleedörfer
- Division of Clinical Cognitive Sciences, Department of Neurology, RWTH Aachen University Hospital, 52074, Aachen, Germany
| | - Harshal Jayeshkumar Patel
- Division of Clinical Cognitive Sciences, Department of Neurology, RWTH Aachen University Hospital, 52074, Aachen, Germany
| | - Alexander Drzezga
- Institute of Neuroscience and Medicine (INM-2), Molecular Organization of the Brain, Forschungszentrum Jülich, 52425, Jülich, Germany
- Department of Nuclear Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937, Cologne, Germany
- German Center for Neurodegenerative Diseases (DZNE), Bonn-Cologne, Germany
| | - David Elmenhorst
- Institute of Neuroscience and Medicine (INM-2), Molecular Organization of the Brain, Forschungszentrum Jülich, 52425, Jülich, Germany
- Department of Nuclear Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937, Cologne, Germany
| | - Ferdinand Binkofski
- Division of Clinical Cognitive Sciences, Department of Neurology, RWTH Aachen University Hospital, 52074, Aachen, Germany
- Institute of Neuroscience and Medicine (INM-4), Forschungszentrum Jülich, Jülich, Germany
| | - Andreas Bauer
- Institute of Neuroscience and Medicine (INM-2), Molecular Organization of the Brain, Forschungszentrum Jülich, 52425, Jülich, Germany
| |
Collapse
|
2
|
A mouse model of hepatic encephalopathy: bile duct ligation induces brain ammonia overload, glial cell activation and neuroinflammation. Sci Rep 2022; 12:17558. [PMID: 36266427 PMCID: PMC9585018 DOI: 10.1038/s41598-022-22423-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 10/14/2022] [Indexed: 01/13/2023] Open
Abstract
Hepatic encephalopathy (HE) is a common complication of chronic liver disease, characterized by an altered mental state and hyperammonemia. Insight into the brain pathophysiology of HE is limited due to a paucity of well-characterized HE models beyond the rat bile duct ligation (BDL) model. Here, we assess the presence of HE characteristics in the mouse BDL model. We show that BDL in C57Bl/6j mice induces motor dysfunction, progressive liver fibrosis, liver function failure and hyperammonemia, all hallmarks of HE. Swiss mice however fail to replicate the same phenotype, underscoring the importance of careful strain selection. Next, in-depth characterisation of metabolic disturbances in the cerebrospinal fluid of BDL mice shows glutamine accumulation and transient decreases in taurine and choline, indicative of brain ammonia overload. Moreover, mouse BDL induces glial cell dysfunction, namely microglial morphological changes with neuroinflammation and astrocyte reactivity with blood-brain barrier (BBB) disruption. Finally, we identify putative novel mechanisms involved in central HE pathophysiology, like bile acid accumulation and tryptophan-kynurenine pathway alterations. Our study provides the first comprehensive evaluation of a mouse model of HE in chronic liver disease. Additionally, this study further underscores the importance of neuroinflammation in the central effects of chronic liver disease.
Collapse
|
3
|
Egorova AV, Baranich TI, Brydun AV, Glinkina VV, Sukhorukov VS. Morphological and Histophysiological Features of the Brain Capillary Endothelium. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022030115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
4
|
Archie SR, Al Shoyaib A, Cucullo L. Blood-Brain Barrier Dysfunction in CNS Disorders and Putative Therapeutic Targets: An Overview. Pharmaceutics 2021; 13:pharmaceutics13111779. [PMID: 34834200 PMCID: PMC8622070 DOI: 10.3390/pharmaceutics13111779] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/15/2021] [Accepted: 10/20/2021] [Indexed: 01/22/2023] Open
Abstract
The blood-brain barrier (BBB) is a fundamental component of the central nervous system (CNS). Its functional and structural integrity is vital to maintain the homeostasis of the brain microenvironment by controlling the passage of substances and regulating the trafficking of immune cells between the blood and the brain. The BBB is primarily composed of highly specialized microvascular endothelial cells. These cells’ special features and physiological properties are acquired and maintained through the concerted effort of hemodynamic and cellular cues from the surrounding environment. This complex multicellular system, comprising endothelial cells, astrocytes, pericytes, and neurons, is known as the neurovascular unit (NVU). The BBB strictly controls the transport of nutrients and metabolites into brain parenchyma through a tightly regulated transport system while limiting the access of potentially harmful substances via efflux transcytosis and metabolic mechanisms. Not surprisingly, a disruption of the BBB has been associated with the onset and/or progression of major neurological disorders. Although the association between disease and BBB disruption is clear, its nature is not always evident, specifically with regard to whether an impaired BBB function results from the pathological condition or whether the BBB damage is the primary pathogenic factor prodromal to the onset of the disease. In either case, repairing the barrier could be a viable option for treating and/or reducing the effects of CNS disorders. In this review, we describe the fundamental structure and function of the BBB in both healthy and altered/diseased conditions. Additionally, we provide an overview of the potential therapeutic targets that could be leveraged to restore the integrity of the BBB concomitant to the treatment of these brain disorders.
Collapse
Affiliation(s)
- Sabrina Rahman Archie
- Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA; (S.R.A.); (A.A.S.)
| | - Abdullah Al Shoyaib
- Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA; (S.R.A.); (A.A.S.)
| | - Luca Cucullo
- Department of Foundational Medical Studies, Oakland University William Beaumont School of Medicine, Rochester, MI 48309, USA
- Correspondence: ; Tel.: +1-248-370-3884; Fax: +1-248-370-4060
| |
Collapse
|
5
|
Ostojic SM. Modulation of CT1 Function: From Klotho Protein to Ammonia and Beyond. Front Nutr 2021; 8:660021. [PMID: 34041260 PMCID: PMC8143434 DOI: 10.3389/fnut.2021.660021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 03/23/2021] [Indexed: 11/13/2022] Open
Affiliation(s)
- Sergej M Ostojic
- FSPE Applied Bioenergetics Lab, University of Novi Sad, Novi Sad, Serbia
| |
Collapse
|
6
|
Chen Z, Ruan J, Li D, Wang M, Han Z, Qiu W, Wu G. The Role of Intestinal Bacteria and Gut-Brain Axis in Hepatic Encephalopathy. Front Cell Infect Microbiol 2021; 10:595759. [PMID: 33553004 PMCID: PMC7859631 DOI: 10.3389/fcimb.2020.595759] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 12/04/2020] [Indexed: 12/12/2022] Open
Abstract
Hepatic encephalopathy (HE) is a neurological disorder that occurs in patients with liver insufficiency. However, its pathogenesis has not been fully elucidated. Pharmacotherapy is the main therapeutic option for HE. It targets the pathogenesis of HE by reducing ammonia levels, improving neurotransmitter signal transduction, and modulating intestinal microbiota. Compared to healthy individuals, the intestinal microbiota of patients with liver disease is significantly different and is associated with the occurrence of HE. Moreover, intestinal microbiota is closely associated with multiple links in the pathogenesis of HE, including the theory of ammonia intoxication, bile acid circulation, GABA-ergic tone hypothesis, and neuroinflammation, which contribute to cognitive and motor disorders in patients. Restoring the homeostasis of intestinal bacteria or providing specific probiotics has significant effects on neurological disorders in HE. Therefore, this review aims at elucidating the potential microbial mechanisms and metabolic effects in the progression of HE through the gut–brain axis and its potential role as a therapeutic target in HE.
Collapse
Affiliation(s)
- Zefeng Chen
- Guangxi Medical University Cancer Hospital, Nanning, China
| | - Jingsheng Ruan
- Guangxi Medical University Cancer Hospital, Nanning, China
| | - Dinghua Li
- Guangxi Medical University Cancer Hospital, Nanning, China
| | - Min Wang
- Guangxi Medical University Cancer Hospital, Nanning, China
| | - Zhiwei Han
- Guangxi Medical University Cancer Hospital, Nanning, China
| | - Wenxia Qiu
- Guangxi Medical University Cancer Hospital, Nanning, China
| | - Guobin Wu
- Guangxi Medical University Cancer Hospital, Nanning, China
| |
Collapse
|
7
|
Kaya M, Ahishali B. Basic physiology of the blood-brain barrier in health and disease: a brief overview. Tissue Barriers 2021; 9:1840913. [PMID: 33190576 PMCID: PMC7849738 DOI: 10.1080/21688370.2020.1840913] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 10/18/2020] [Accepted: 10/19/2020] [Indexed: 12/18/2022] Open
Abstract
The blood-brain barrier (BBB), a dynamic interface between blood and brain constituted mainly by endothelial cells of brain microvessels, robustly restricts the entry of potentially harmful blood-sourced substances and cells into the brain, however, many therapeutically active agents concurrently cannot gain access into the brain at effective doses in the presence of an intact barrier. On the other hand, breakdown of BBB integrity may involve in the pathogenesis of various neurodegenerative diseases. Besides, certain diseases/disorders such as Alzheimer's disease, hypertension, and epilepsy are associated with varying degrees of BBB disruption. In this review, we aim to highlight the current knowledge on the cellular and molecular composition of the BBB with special emphasis on the major transport pathways across the barrier type endothelial cells. We further provide a discussion on the innovative brain drug delivery strategies in which the obstacle formed by BBB interferes with effective pharmacological treatment of neurodegenerative diseases/disorders.
Collapse
Affiliation(s)
- Mehmet Kaya
- Koç University School of Medicine Department of Physiology, Koç University Research Center for Translational Medicine, Istanbul, Turkey
| | - Bulent Ahishali
- Koç University School of Medicine Department of Histology and Embryology, Koç University Research Center for Translational Medicine, Istanbul, Turkey
| |
Collapse
|
8
|
Vairappan B, Sundhar M, Srinivas BH. Resveratrol Restores Neuronal Tight Junction Proteins Through Correction of Ammonia and Inflammation in CCl 4-Induced Cirrhotic Mice. Mol Neurobiol 2018; 56:4718-4729. [PMID: 30377987 DOI: 10.1007/s12035-018-1389-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 10/11/2018] [Indexed: 12/31/2022]
Abstract
Systemic inflammation and ammonia (hyperammonemia) act synergistically in the pathogenesis of hepatic encephalopathy (HE), the neurobehavioral sequelae of advanced liver disease. In cirrhotic patients, we have recently observed elevated levels of circulating neuronal tight junction (TJ) protein, zonula occludens 1 (ZO-1), reflective of a change to blood-brain barrier (BBB) integrity. Moreover, ZO-1 levels positively correlated with hyperammonemia, although any potential relationship remains unclear. Using a carbon tetrachloride (CCl4)-induced mouse model of cirrhosis, we primarily looked to explore the relationship between neuronal TJ protein expression and hyperammonemia. Secondarily, we assessed the potential role of a natural antioxidant, resveratrol, on neuronal TJ protein expression and hyperammonemia. Over 12 weeks, male Swiss mice were randomized (n = 8/group) to either naïve controls or induced cirrhosis, using two doses of intraperitoneal CCl4 (0.5 ml/kg/week). After 12 weeks, naïve and cirrhotic mice were randomized to receive either 2 weeks of par-oral resveratrol (10 mg/kg). Plasma samples were analyzed for ammonia, liver biochemistry (ALT, AST, albumin, and bilirubin), and pro-inflammatory cytokines (TNF-α and IL-1β), and brain tissue for brain water content, TJ protein expression (e.g., ZO-1, claudin 5, and occludin), and tissue oxidative stress and inflammatory markers (NF-κB and iNOS) using western blotting. Compared to naïve mice, cirrhosis significantly increased circulating ammonia, brain water, ALT, AST, TNF-α, IL-1β, 4HNE, NF-κB, and iNOS levels, with a concomitant reduction in all TJ proteins (P < 0.05, respectively). In cirrhotic mice, resveratrol treatment ameliorated these changes significantly (P < 0.05, respectively). Our findings provide evidence for a causal association between hyperammonemia and inflammation in cirrhosis linked to TJ protein alterations, BBB disruption, and HE predilection. Moreover, this is the first report of a potential role for resveratrol as a novel therapeutic approach to managing neurological sequelae complicating cirrhosis.
Collapse
Affiliation(s)
- Balasubramaniyan Vairappan
- Liver Diseases Research Lab, Department of Biochemistry, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Dhanvantari Nagar, Pondicherry, 605 006, India.
| | - M Sundhar
- Liver Diseases Research Lab, Department of Biochemistry, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Dhanvantari Nagar, Pondicherry, 605 006, India
| | - B H Srinivas
- Department of Pathology, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, 605006, India
| |
Collapse
|
9
|
Crosby LM, Tatu CA, Varonka M, Charles KM, Orem WH. Toxicological and chemical studies of wastewater from hydraulic fracture and conventional shale gas wells. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2018; 37:2098-2111. [PMID: 29630745 DOI: 10.1002/etc.4146] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 02/02/2018] [Accepted: 03/23/2018] [Indexed: 06/08/2023]
Abstract
New technology has enabled recovery of inaccessible natural gas shale deposits; however, the potential impacts to human health from the migration of brines into drinking water or surface spills are unknown. To provide information that can inform these potential impacts, chemical characterization and in vitro toxicologic testing were conducted using pre- and postinjection waters from conventional and unconventional oil and gas wells. Wastewater concentrations may be diluted or reduced by fate and transport processes when released into the environment by unknown amounts, and laboratory studies only imply potential effects. In acute cytotoxicity and wound healing assays, there was dose-dependent toxicity in human and rat cells with growth promotion at low concentrations. Lethality was measured in time studies up to 10 d postinjection. Produced water samples from both well types were equally toxic to human cells and were corrosive at high concentrations. Measurement of protein and gene expression identified metabolic pathways responding to both well types as NADPH quinone oxidoreductase oxidative stress-responsive enzyme and tight junction protein genes. A KCl sample of matched ionic strength showed a different toxicity profile from produced waters, indicating that salts alone were not the cause of toxicity. Organic chemicals and branched alkanes were present in hydraulic fracture wells, and mainly branched alkanes were present in conventional wells. One organic substance was still present after 240 d. The known properties of these chemicals include potential toxicity to multiple human organs, sensitization, irritation, developmental effects, and tumor promotion, depending on the concentrations and synergistic effects of chemicals during exposure. Environ Toxicol Chem 2018;37:2098-2111. © 2018 SETAC.
Collapse
Affiliation(s)
| | - Calin A Tatu
- US Geological Survey, Reston, VA
- Department of Biology, University of Medicine and Pharmacy, Timisoara, Romania
| | | | | | | |
Collapse
|
10
|
Liu XM, Peyton KJ, Durante W. Ammonia promotes endothelial cell survival via the heme oxygenase-1-mediated release of carbon monoxide. Free Radic Biol Med 2017; 102:37-46. [PMID: 27867098 PMCID: PMC5209302 DOI: 10.1016/j.freeradbiomed.2016.11.029] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 11/03/2016] [Accepted: 11/16/2016] [Indexed: 01/07/2023]
Abstract
Although endothelial cells produce substantial quantities of ammonia during cell metabolism, the physiologic role of this gas in these cells is not known. In this study, we investigated if ammonia regulates the expression of heme oxygenase-1 (HO-1), and if this enzyme influences the biological actions of ammonia on endothelial cells. Exogenously administered ammonia, given as ammonium chloride or ammonium hydroxide, or endogenously generated ammonia stimulated HO-1 protein expression in cultured human and murine endothelial cells. Dietary supplementation of ammonia also induced HO-1 protein expression in murine arteries. The increase in HO-1 protein by ammonia in endothelial cells was first detected 4h after ammonia exposure and was associated with the induction of HO-1 mRNA, enhanced production of reactive oxygen species (ROS), and increased expression and activity of NF-E2-related factor-2 (Nrf2). Ammonia also activated the HO-1 promoter and this was blocked by mutating the antioxidant responsive element or by overexpressing dominant-negative Nrf2. The induction of HO-1 expression by ammonia was dependent on ROS formation and prevented by N-acetylcysteine or rotenone. Finally, prior treatment of endothelial cells with ammonia inhibited tumor necrosis factor-α-stimulated cell death. However, silencing HO-1 expression abrogated the protective action of ammonia and this was reversed by the administration of carbon monoxide but not bilirubin or iron. In conclusion, this study demonstrates that ammonia stimulates the expression of HO-1 in endothelial cells via the ROS-Nrf2 pathway, and that the induction of HO-1 contributes to the cytoprotective action of ammonia by generating carbon monoxide. Moreover, it identifies ammonia as a potentially important signaling gas in the vasculature that promotes endothelial cell survival.
Collapse
Affiliation(s)
- Xiao-Ming Liu
- Department of Medical Pharmacology and Physiology, School of Medicine, University of Missouri-Columbia, M409 Medical Sciences Building, One Hospital Drive, Columbia, MO 65212, USA
| | - Kelly J Peyton
- Department of Medical Pharmacology and Physiology, School of Medicine, University of Missouri-Columbia, M409 Medical Sciences Building, One Hospital Drive, Columbia, MO 65212, USA
| | - William Durante
- Department of Medical Pharmacology and Physiology, School of Medicine, University of Missouri-Columbia, M409 Medical Sciences Building, One Hospital Drive, Columbia, MO 65212, USA.
| |
Collapse
|
11
|
Ren Q, Li M, Yuan L, Song M, Xing X, Shi G, Meng F, Wang R. Acute ammonia toxicity in crucian carp Carassius auratus and effects of taurine on hyperammonemia. Comp Biochem Physiol C Toxicol Pharmacol 2016; 190:9-14. [PMID: 27510860 DOI: 10.1016/j.cbpc.2016.08.001] [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: 06/16/2016] [Revised: 07/28/2016] [Accepted: 08/02/2016] [Indexed: 12/18/2022]
Abstract
The four experimental groups were carried out to test the response of crucian carp Carassius auratus to ammonia toxicity and taurine: group 1 was injected with NaCl, group 2 was injected with ammonium acetate, group 3 was injected with ammonium acetate and taurine, and group 4 was injected with taurine. Fish in group 2 had the highest ammonia and glutamine contents, and the lowest glutamate content in liver and brain. Serum superoxide dismutase (SOD), glutathione (GSH) activities, red cell count (RBC), white cell count (WBC), lysozyme (LYZ) activity, complement C3 content of fish in group 2 reflected the lowest, but malondialdehyde content was the highest. Importantly, serum SOD and GSH activites, RBC, WBC, and LYZ activity, C3, C4 and total immunoglobulin contents of fish in group 3 were significantly higher than those of fish in group 2. This study indicates that ammonia exerts its toxic effects by interfering with amino acid transport, inducing ROS generation, leading to malondialdehyde accumulation and immunosuppression of crucian carp. The exogenous taurine could mitigate the adverse effect of high ammonia level on fish physiological disorder.
Collapse
Affiliation(s)
- Qianyan Ren
- School of Marine Sciences, Ningbo University, Ningbo 315211, China; College of Marine Science, Zhejiang Ocean University, Zhoushan 316000, China
| | - Ming Li
- School of Marine Sciences, Ningbo University, Ningbo 315211, China.
| | - Lixia Yuan
- School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Meize Song
- College of Marine Science, Zhejiang Ocean University, Zhoushan 316000, China
| | - Xiaodan Xing
- College of Marine Science, Zhejiang Ocean University, Zhoushan 316000, China
| | - Ge Shi
- College of Marine Science, Zhejiang Ocean University, Zhoushan 316000, China
| | - Fanxing Meng
- School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Rixin Wang
- School of Marine Sciences, Ningbo University, Ningbo 315211, China.
| |
Collapse
|
12
|
Rackayova V, Cudalbu C, Pouwels PJW, Braissant O. Creatine in the central nervous system: From magnetic resonance spectroscopy to creatine deficiencies. Anal Biochem 2016; 529:144-157. [PMID: 27840053 DOI: 10.1016/j.ab.2016.11.007] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 11/08/2016] [Accepted: 11/09/2016] [Indexed: 10/20/2022]
Abstract
Creatine (Cr) is an important organic compound acting as intracellular high-energy phosphate shuttle and in energy storage. While located in most cells where it plays its main roles in energy metabolism and cytoprotection, Cr is highly concentrated in muscle and brain tissues, in which Cr also appears to act in osmoregulation and neurotransmission. This review discusses the basis of Cr metabolism, synthesis and transport within brain cells. The importance of Cr in brain function and the consequences of its impaired metabolism in primary and secondary Cr deficiencies are also discussed. Cr and phosphocreatine (PCr) in living systems can be well characterized using in vivo magnetic resonance spectroscopy (MRS). This review describes how 1H MRS allows the measurement of Cr and PCr, and how 31P MRS makes it possible to estimate the creatine kinase (CK) rate constant and so detect dynamic changes in the Cr/PCr/CK system. Absolute quantification by MRS using creatine as internal reference is also debated. The use of in vivo MRS to study brain Cr in a non-invasive way is presented, as well as its use in clinical and preclinical studies, including diagnosis and treatment follow-up in patients.
Collapse
Affiliation(s)
- Veronika Rackayova
- Laboratory of Functional and Metabolic Imaging (LIFMET), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Cristina Cudalbu
- Centre d'Imagerie Biomedicale (CIBM), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Petra J W Pouwels
- Department of Physics and Medical Technology, VU University Medical Center, Amsterdam, The Netherlands
| | - Olivier Braissant
- Service of Biomedicine, Neurometabolic Unit, Lausanne University Hospital, Lausanne, Switzerland.
| |
Collapse
|
13
|
Immortalized endothelial cell lines for in vitro blood–brain barrier models: A systematic review. Brain Res 2016; 1642:532-545. [DOI: 10.1016/j.brainres.2016.04.024] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 04/05/2016] [Accepted: 04/12/2016] [Indexed: 12/18/2022]
|
14
|
Abstract
A 7-year-old, spayed female, Wheaton terrier dog was icteric, lethargic, and anorexic with increased activity of hepatocellular and cholestatic liver enzymes and an extreme hyperbilirubinemia level of 609 μmol/L (reference interval: 1.0–4.0 μmol/L). Necropsy findings included profound icterus and red and yellow mottling of the liver. Yellow discoloration of the thalamic and subthalamic nuclei was detected on subgross examination of the formalin-fixed brain. Histologic examination of the brain revealed neuronal necrosis within the discolored nuclei, necrosis of Purkinje cells, and Alzheimer type II astrocytes in the cerebrocortical gray matter and in the nuclei, with gross discoloration. Histologic examination of the liver revealed extensive necrosis in a periacinar-to-bridging pattern and often extending to portal triads. A case of naturally occurring kernicterus in an adult dog secondary to extreme hyperbilirubinemia resulting from fulminant hepatic failure is reported. The few reports of this disease in domestic species involved neonates, namely 1 foal and 1 kitten.
Collapse
Affiliation(s)
- C R Sangster
- Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, S7N 5B4, Canada
| | | | | | | | | |
Collapse
|
15
|
Abstract
The purpose of this review is to describe the endocrine and local testicular factors that contribute to the regulation of the blood-testis barrier (BTB), using information gained from in vivo and in vitro models of BTB formation during/after puberty, and from the maintenance of BTB function during adulthood. In vivo the BTB, in part comprised of tight junctions between adjacent somatic Sertoli cells, compartmentalizes meiotic spermatocytes and post-meiotic spermatids away from the vasculature, and therefore prevents autoantibody production by the immune system against these immunogenic germ cells. This adluminal compartment also features a unique biochemical milieu required for the completion of germ cell development. During the normal process of spermatogenesis, earlier germ cells continually cross into the adluminal compartment, but the regulatory mechanisms and changes in junctional proteins that allow this translocation step without causing a 'leak' remain poorly understood. Recent data describing the roles of FSH and androgen on the regulation of Sertoli cell tight junctions and tight junction proteins will be discussed, followed by an examination of the role of paracrine factors, including members of the TGFβ superfamily (TGFβ3, activin A) and retinoid signalling, as potential mediators of junction assembly and disassembly during the translocation process.
Collapse
Affiliation(s)
- Peter G Stanton
- Hudson Institute of Medical Research, Clayton, Victoria, Australia; Dept. of Molecular and Translational Sciences, Monash University, Clayton, Victoria, Australia.
| |
Collapse
|
16
|
Chistiakov DA, Orekhov AN, Bobryshev YV. Endothelial Barrier and Its Abnormalities in Cardiovascular Disease. Front Physiol 2015; 6:365. [PMID: 26696899 PMCID: PMC4673665 DOI: 10.3389/fphys.2015.00365] [Citation(s) in RCA: 162] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 11/16/2015] [Indexed: 01/15/2023] Open
Abstract
Endothelial cells (ECs) form a unique barrier between the vascular lumen and the vascular wall. In addition, the endothelium is highly metabolically active. In cardiovascular disease such as atherosclerosis and hypertension, normal endothelial function could be severely disturbed leading to endothelial dysfunction that then could progress to complete and irreversible loss of EC functionality and contribute to entire vascular dysfunction. Proatherogenic stimuli such as diabetes, dyslipidemia, and oxidative stress could initiate endothelial dysfunction and in turn vascular dysfunction and lead to the development of atherosclerotic arterial disease, a background for multiple cardiovascular disorders including coronary artery disease, acute coronary syndrome, stroke, and thrombosis. Intercellular junctions between ECs mediate the barrier function. Proinflammatory stimuli destabilize the junctions causing the disruption of the endothelial barrier and increased junctional permeability. This facilitates transendothelial migration of immune cells to the arterial intima and induction of vascular inflammation. Proatherogenic stimuli attack endothelial microtubule function that is regulated by acetylation of tubulin, an essential microtubular constituent. Chemical modification of tubulin caused by cardiometabolic risk factors and oxidative stress leads to reorganization of endothelial microtubules. These changes destabilize vascular integrity and increase permeability, which finally results in increasing cardiovascular risk.
Collapse
Affiliation(s)
- Dimitry A Chistiakov
- Division of Laboratory Medicine, Department of Molecular Genetic Diagnostics and Cell Biology, Research Center for Children's Health, Institute of Pediatrics Moscow, Russia
| | - Alexander N Orekhov
- Laboratory of Angiopathology, Institute of General Pathology and Pathophysiology, Russian Academy of Sciences Moscow, Russia ; Department of Biophysics, Biological Faculty, Moscow State University Moscow, Russia ; Institute for Atherosclerosis Research, Skolkovo Innovation Center Moscow, Russia
| | - Yuri V Bobryshev
- Faculty of Medicine, School of Medical Sciences, University of New South Wales Sydney, NSW, Australia ; School of Medicine, University of Western Sydney Campbelltown, NSW, Australia
| |
Collapse
|
17
|
Haseloff RF, Dithmer S, Winkler L, Wolburg H, Blasig IE. Transmembrane proteins of the tight junctions at the blood-brain barrier: structural and functional aspects. Semin Cell Dev Biol 2014; 38:16-25. [PMID: 25433243 DOI: 10.1016/j.semcdb.2014.11.004] [Citation(s) in RCA: 221] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 11/14/2014] [Indexed: 01/27/2023]
Abstract
The blood-brain barrier (BBB) is formed by microvascular endothelial cells sealed by tetraspanning tight junction (TJ) proteins, such as claudins and TAMPs (TJ-associated marvel proteins, occludin and tricellulin). Claudins are the major components of the TJs. At the BBB, claudin-5 dominates the TJs by preventing the paracellular permeation of small molecules. On the other hand, TAMPs regulate the structure and function of the TJs; tricellulin may tighten the barrier for large molecules. This review aims at integrating and summarizing the most relevant and recent work on how the BBB is influenced by claudin-1, -3, -5, -12 and the TAMPs occludin and tricellulin, all of which are four-transmembrane TJ proteins. The exact functions of claudin-1, -3, -12 and TAMPs at this barrier still need to be elucidated.
Collapse
Affiliation(s)
- Reiner F Haseloff
- Leibniz Institute for Molecular Pharmacology, Robert Roessle-Str. 10, 13125 Berlin, Germany
| | - Sophie Dithmer
- Leibniz Institute for Molecular Pharmacology, Robert Roessle-Str. 10, 13125 Berlin, Germany
| | - Lars Winkler
- Leibniz Institute for Molecular Pharmacology, Robert Roessle-Str. 10, 13125 Berlin, Germany
| | - Hartwig Wolburg
- Leibniz Institute for Molecular Pharmacology, Robert Roessle-Str. 10, 13125 Berlin, Germany
| | - Ingolf E Blasig
- Leibniz Institute for Molecular Pharmacology, Robert Roessle-Str. 10, 13125 Berlin, Germany.
| |
Collapse
|
18
|
van de Kamp JM, Mancini GM, Salomons GS. X-linked creatine transporter deficiency: clinical aspects and pathophysiology. J Inherit Metab Dis 2014; 37:715-33. [PMID: 24789340 DOI: 10.1007/s10545-014-9713-8] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 03/27/2014] [Accepted: 04/01/2014] [Indexed: 12/22/2022]
Abstract
Creatine transporter deficiency was discovered in 2001 as an X-linked cause of intellectual disability characterized by cerebral creatine deficiency. This review describes the current knowledge regarding creatine metabolism, the creatine transporter and the clinical aspects of creatine transporter deficiency. The condition mainly affects the brain while other creatine requiring organs, such as the muscles, are relatively spared. Recent studies have provided strong evidence that creatine synthesis also occurs in the brain, leading to the intriguing question of why cerebral creatine is deficient in creatine transporter deficiency. The possible mechanisms explaining the cerebral creatine deficiency are discussed. The creatine transporter knockout mouse provides a good model to study the disease. Over the past years several treatment options have been explored but no treatment has been proven effective. Understanding the pathogenesis of creatine transporter deficiency is of paramount importance in the development of an effective treatment.
Collapse
MESH Headings
- Amino Acid Metabolism, Inborn Errors/diagnosis
- Amino Acid Metabolism, Inborn Errors/drug therapy
- Amino Acid Metabolism, Inborn Errors/genetics
- Amino Acid Metabolism, Inborn Errors/pathology
- Animals
- Brain Diseases, Metabolic, Inborn/complications
- Brain Diseases, Metabolic, Inborn/genetics
- Brain Diseases, Metabolic, Inborn/physiopathology
- Creatine/deficiency
- Creatine/genetics
- Genetic Diseases, X-Linked/genetics
- Humans
- Intellectual Disability/etiology
- Intellectual Disability/genetics
- Membrane Transport Proteins/deficiency
- Membrane Transport Proteins/genetics
- Mental Retardation, X-Linked/complications
- Mental Retardation, X-Linked/genetics
- Mental Retardation, X-Linked/physiopathology
- Mice
- Plasma Membrane Neurotransmitter Transport Proteins/deficiency
- Plasma Membrane Neurotransmitter Transport Proteins/genetics
Collapse
Affiliation(s)
- Jiddeke M van de Kamp
- Department of Clinical Genetics, VU University Medical Center, P.O. Box 7057, 1007 MB, Amsterdam, The Netherlands,
| | | | | |
Collapse
|
19
|
Hwang I, Yang H, Kang HS, Ahn CH, Lee GS, Hong EJ, An BS, Jeung EB. Spatial expression of claudin family members in various organs of mice. Mol Med Rep 2014; 9:1806-12. [PMID: 24626855 DOI: 10.3892/mmr.2014.2031] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2013] [Accepted: 02/17/2014] [Indexed: 11/05/2022] Open
Abstract
Claudins (CLDNs) are tetraspan transmembrane proteins, which are components of tight junctions. The CLDN family is composed of 27 members that are responsible for paracellular transport and certain CLDNs form charge-selective ion channels. CLDNs have two extracellular loops, and the charge of the first extracellular loop determines the ion selectivity of each CLDN. Although the expression and function of each CLDN have been previously investigated, the distribution of CLDNs in various target organs remains to be determined. In the present study, the tissue-specific mRNA distribution of CLDNs (1-5, 7-8, 10a and b, 11-12, 14-17 and 19) in the duodenum, ileum, colon, kidney, liver and lung were defined. Among the tested CLDNs, CLDN1, 2, 12 and 16 were selected for further investiagtion. It was observed that CLDN1, CLDN2 and CLDN12 transcripts and proteins were particularly abundant in the investigated organs. Notably, immune-reactive CLDN16 was detected in a tissue-specific manner and shown in the renal tubules and portal vein. The tested CLDNs were localized to intercellular apical junctions in the epithelium of the intestine, renal tubule and bronchus. Based on this novel information, the presence of several types of CLDNs is of interest as CLDNs may promote or dampen the paracellular diffusion of specific ions.
Collapse
Affiliation(s)
- Inho Hwang
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea
| | - Hyun Yang
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea
| | - Hong-Seok Kang
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea
| | - Chang-Hwan Ahn
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea
| | - Geun-Shik Lee
- Laboratory of Veterinary Physiology, College of Veterinary Medicine, Kangwon National University, Chuncheon, Gangwon 200‑701, Republic of Korea
| | - Eui-Ju Hong
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea
| | - Beum-Soo An
- Department of Biomaterials Science, College of National Resources and Life Science, Pusan National University, Miryang, Pusan 627‑706, Republic of Korea
| | - Eui-Bae Jeung
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361‑763, Republic of Korea
| |
Collapse
|
20
|
Haverfield JT, Meachem SJ, Nicholls PK, Rainczuk KE, Simpson ER, Stanton PG. Differential permeability of the blood-testis barrier during reinitiation of spermatogenesis in adult male rats. Endocrinology 2014; 155:1131-44. [PMID: 24424039 DOI: 10.1210/en.2013-1878] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The blood-testis barrier (BTB) sequesters meiotic spermatocytes and differentiating spermatids away from the vascular environment. We aimed to assess whether meiosis and postmeiotic differentiation could occur when the BTB is permeable. Using a model of meiotic suppression and reinitiation, BTB function was assessed using permeability tracers of small, medium, and large (0.6-, 70-, and 150-kDa) sizes to emulate blood- and lymphatic-borne factors that could cross the BTB. Adult rats (n = 9/group) received the GnRH antagonist acyline (10 wk) to suppress gonadotropins, followed by testosterone (24cm Silastic implant), for 2, 4, 7, 10, 15, and 35 days. In acyline-suppressed testes, all tracers permeated the seminiferous epithelium. As spermatocytes up to diplotene stage XIII reappeared, both the 0.6- and 70-kDa tracers, but not 150 kDa, permeated around these cells. Intriguingly, the 0.6- and 70-kDa tracers were excluded from pachytene spermatocytes at stages VII and VIII but not in subsequent stages. The BTB became progressively impermeable to the 0.6- and 70-kDa tracers as stages IV-VII round spermatids reappeared in the epithelium. This coincided with the appearance of the tight junction protein, claudin-12, in Sertoli cells and at the BTB. We conclude that meiosis can occur when the BTB is permeable to factors up to 70 kDa during the reinitiation of spermatogenesis. Moreover, BTB closure corresponds with the presence of particular pachytene spermatocytes and round spermatids. This research has implications for understanding the effects of BTB dynamics in normal spermatogenesis and also potentially in states where spermatogenesis is suppressed, such as male hormonal contraception or infertility.
Collapse
Affiliation(s)
- Jenna T Haverfield
- Prince Henry's Institute (J.T.H., S.J.M., P.K.N., K.E.R., E.R.S., P.G.S.), Monash Medical Centre, Clayton, VIC 3168, Australia; and Departments of Anatomy and Developmental Biology (J.T.H., S.J.M.) and Biochemistry and Molecular Biology (P.K.N., E.R.S., P.G.S.), Monash University, Clayton, VIC 3800, Australia
| | | | | | | | | | | |
Collapse
|
21
|
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: 176] [Impact Index Per Article: 16.0] [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.
Collapse
Affiliation(s)
- Olivier Braissant
- Service of Biomedicine, Lausanne University Hospital, Avenue Pierre-Decker 2, CI 02/33, CH-1011 Lausanne, Switzerland.
| | | | | |
Collapse
|
22
|
Sohet F, Daneman R. Genetic mouse models to study blood-brain barrier development and function. Fluids Barriers CNS 2013; 10:3. [PMID: 23305182 PMCID: PMC3675378 DOI: 10.1186/2045-8118-10-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Accepted: 11/20/2012] [Indexed: 12/21/2022] Open
Abstract
The blood–brain barrier (BBB) is a complex physiological structure formed by the blood vessels of the central nervous system (CNS) that tightly regulates the movement of substances between the blood and the neural tissue. Recently, the generation and analysis of different genetic mouse models has allowed for greater understanding of BBB development, how the barrier is regulated during health, and its response to disease. Here we discuss: 1) Genetic mouse models that have been used to study the BBB, 2) Available mouse genetic tools that can aid in the study of the BBB, and 3) Potential tools that if generated could greatly aid in our understanding of the BBB.
Collapse
Affiliation(s)
- Fabien Sohet
- UCSF Department of Anatomy, 513 Parnassus Ave HSW1301, San Francisco, 94117, California, USA.
| | | |
Collapse
|
23
|
Ghosh S, Sengupta A, Sharma S, Sonawat HM. Metabolic fingerprints of serum, brain, and liver are distinct for mice with cerebral and noncerebral malaria: a ¹H NMR spectroscopy-based metabonomic study. J Proteome Res 2012; 11:4992-5004. [PMID: 22838963 DOI: 10.1021/pr300562m] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cerebral malaria (CM) is a life-threatening disease in humans caused by Plasmodium falciparum, leading to high mortality. Plasmodium berghei ANKA (PbA) infection in C57Bl/6 mice induces pathologic symptoms similar to that in human CM. However, experimental CM incidence in mice is variable, and there are no known metabolic correlates/fingerprints for the animals that develop CM. Here, we have used (1)H NMR-based metabonomics to investigate the metabolic changes in the mice with CM with respect to the mice that have noncerebral malaria (NCM) of the same batchmates with identical genetic backgrounds and infected simultaneously. The metabolic profile of the infected mice (both CM and NCM) was separately compared with the metabolite profile of uninfected control mice of same genetic background. The objective of this study was to search for metabolic changes/fingerprints of CM and identify the pathways that might be differentially altered in mice that succumbed to CM. The results show that brain, liver, and sera exhibit unique metabolic fingerprints for CM over NCM mice. Some of the major fingerprints are increased level of triglycerides, VLDL-cholesterol in sera of CM mice, and decreased levels of glutamine in the sera concomitant with increased levels of glutamine in the brain of the mice with CM. Moreover, glycerophosphocholine is decreased in both the brain and the liver of animals with CM, and myo-inositol and histamine are increased in the liver of CM mice. The metabolic fingerprints in brain, sera, and liver of mice with CM point toward perturbation in the ammonia detoxification pathway and perturbation in lipid and choline metabolism in CM specifically. The study helps us to understand the severity of CM over NCM and in unrevealing the specific metabolic pathways that are compromised in CM.
Collapse
Affiliation(s)
- Soumita Ghosh
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
| | | | | | | |
Collapse
|
24
|
Braissant O. Creatine and guanidinoacetate transport at blood-brain and blood-cerebrospinal fluid barriers. J Inherit Metab Dis 2012; 35:655-64. [PMID: 22252611 DOI: 10.1007/s10545-011-9433-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 11/22/2011] [Accepted: 11/30/2011] [Indexed: 10/14/2022]
Abstract
While it was thought that most of cerebral creatine is of peripheral origin, AGAT and GAMT are well expressed in CNS where brain cells synthesize creatine. While the creatine transporter SLC6A8 is expressed by microcapillary endothelial cells (MCEC) at blood-brain barrier (BBB), it is absent from their surrounding astrocytes. This raised the concept that BBB has a limited permeability for peripheral creatine, and that the brain supplies a part of its creatine by endogenous synthesis. This review brings together the latest data on creatine and guanidinoacetate transport through BBB and blood-CSF barrier (BCSFB) with the clinical evidence of AGAT-, GAMT- and SLC6A8-deficient patients, in order to delineate a clearer view on the roles of BBB and BCSFB in the transport of creatine and guanidinoacetate between periphery and CNS, and on brain synthesis and transport of creatine. It shows that in physiological conditions, creatine is taken up by CNS from periphery through SLC6A8 at BBB, but in limited amounts, and that CNS also needs its own creatine synthesis. No uptake of guanidinoacetate from periphery occurs at BBB except under GAMT deficiency, but a net exit of guanidinoacetate seems to occur from CSF to blood at BCSFB, predominantly through the taurine transporter TauT.
Collapse
Affiliation(s)
- Olivier Braissant
- Inborn Errors of Metabolism, Service of Biomedicine, Lausanne University Hospital, Avenue Pierre-Decker 2, CI 02/33, CH-1011, Lausanne, Switzerland.
| |
Collapse
|
25
|
Schrade A, Sade H, Couraud PO, Romero IA, Weksler BB, Niewoehner J. Expression and localization of claudins-3 and -12 in transformed human brain endothelium. Fluids Barriers CNS 2012; 9:6. [PMID: 22373538 PMCID: PMC3305566 DOI: 10.1186/2045-8118-9-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 02/29/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The aim of this study was to characterize the hCMEC/D3 cell line, an in vitro model of the human Blood Brain Barrier (BBB) for the expression of brain endothelial specific claudins-3 and -12. FINDINGS hCMEC/D3 cells express claudins-3 and -12. Claudin-3 is distinctly localized to the TJ whereas claudin -12 is observed in the perinuclear region and completely absent from TJs. We show that the expression of both proteins is lost in cell passage numbers where the BBB properties are no longer fully conserved. Expression and localization of claudin-3 is not modulated by simvastatin shown to improve barrier function in vitro and also recommended for routine hCMEC/D3 culture. CONCLUSIONS These results support conservation of claudin-3 and -12 expression in the hCMEC/D3 cell line and make claudin-3 a potential marker for BBB characteristics in vitro.
Collapse
Affiliation(s)
- Anja Schrade
- Pharma Research and Early Development (pRED), LMR Penzberg, Roche, Penzberg, Germany.
| | | | | | | | | | | |
Collapse
|
26
|
Skowrońska M, Zielińska M, Wójcik-Stanaszek L, Ruszkiewicz J, Milatovic D, Aschner M, Albrecht J. Ammonia increases paracellular permeability of rat brain endothelial cells by a mechanism encompassing oxidative/nitrosative stress and activation of matrix metalloproteinases. J Neurochem 2012; 121:125-34. [PMID: 22260250 DOI: 10.1111/j.1471-4159.2012.07669.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Ammonia is responsible for cerebral edema associated with acute liver failure, but the role of the vasogenic mechanism has been a matter of dispute. Here, we tested the hypothesis that ammonia induces changes in blood-brain barrier (BBB) permeability by a mechanism coupled to oxidative/nitrosative stress (ONS) evoked in the BBB-forming cerebral capillary endothelial cells. Treatment of a rat brain endothelial cell line with ammonia (5 mmol/L, 24 h) caused accumulation of ONS markers: reactive oxygen species, nitric oxide and peroxidation products of phospholipid-bound arachidonic acid, F2-isoprostanes. Concurrently, ammonia increased the activity of extracellular matrix metalloproteinases (MMP-2/MMP-9), increased cell permeability to fluorescein isothiocyanate-dextran (40 kDa), and increased the expression of y+LAT2, a transporter that mediates the uptake to the cells of the nitric oxide precursor, arginine. The increase of cell permeability was ameliorated upon co-treatment with a MMP inhibitor, SB-3CT and with an antioxidant, glutathione diethyl ester, which also reduced F2-isoprostanes. Ammonia-induced ONS was attenuated by cytoprotective agents l-ornithine, phenylbutyrate, and their conjugate l-ornithine phenylbutyrate, an ammonia-trapping drug used to treat hyperammonemia. The results support the concept that ONS and ONS-related activation of MMPs in cerebral capillary endothelial cells contribute to the alterations in BBB permeability and to the vasogenic component of cerebral edema associated with acute liver failure.
Collapse
Affiliation(s)
- Marta Skowrońska
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | | | | | | | | | | | | |
Collapse
|
27
|
Chasiotis H, Kolosov D, Kelly SP. Permeability properties of the teleost gill epithelium under ion-poor conditions. Am J Physiol Regul Integr Comp Physiol 2011; 302:R727-39. [PMID: 22204956 DOI: 10.1152/ajpregu.00577.2011] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Permeability properties of the goldfish gill epithelium were examined in vivo and in vitro following exposure to ion-poor water (IPW) conditions. In gill tissue of IPW-acclimated goldfish, transcript abundance of tight junction (TJ) proteins occludin, claudin-b, -d, -e, -h, -7, and -8d increased, whereas ZO-1 and claudin 12 mRNA decreased and claudin-c was unaltered. In association with these changes, TJ depth increased among gill pavement cells (PVCs) and gill PVCs and mitochondria-rich cells (MRCs). PVC and MRC gill cell fractions were isolated using Percoll. Transcripts encoding for occludin, claudin-b, -c, -d, -e, -h, -7, -8d, -12, and ZO-1 were present in both fractions. After IPW acclimation, occludin, claudin-b and -e, and ZO-1 mRNA abundance increased in both fractions. In contrast, claudin-8d mRNA abundance increased in PVCs only while claudin-h decreased in MRCs. Gill permeability was examined using primary cultured goldfish PVC epithelia supplemented with serum derived from IPW-acclimated goldfish. IPW serum supplementation increased transepithelial resistance, reduced [(3)H]PEG-4000 permeability, and enhanced epithelial integrity during in vitro IPW exposure. IPW serum increased mRNA abundance of occludin, claudin-8d and -e in vitro. Using small interfering RNA, we found that occludin abundance was decreased in cultured gill epithelia, resulting in an increase in [(3)H]PEG-4000 flux. As occludin increased in the gills of IPW-acclimated fish as well as cultured gill epithelia exposed to IPW serum, results suggest that occludin is a barrier-forming TJ protein in fish gill epithelia. These studies support the idea that TJ proteins play an important role in regulating gill permeability in IPW.
Collapse
Affiliation(s)
- Helen Chasiotis
- Department of Biology, York University, Toronto, Ontario, Canada
| | | | | |
Collapse
|
28
|
Hirase T, Node K. Endothelial dysfunction as a cellular mechanism for vascular failure. Am J Physiol Heart Circ Physiol 2011; 302:H499-505. [PMID: 22081698 DOI: 10.1152/ajpheart.00325.2011] [Citation(s) in RCA: 155] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The regulation of vascular tone, vascular permeability, and thromboresistance is essential to maintain blood circulation and therefore tissue environments under physiological conditions. Atherogenic stimuli, including diabetes, dyslipidemia, and oxidative stress, induce vascular dysfunction, leading to atherosclerosis, which is a key pathological basis for cardiovascular diseases such as ischemic heart disease and stroke. We have proposed a novel concept termed "vascular failure" to comprehensively recognize the vascular dysfunction that contributes to the development of cardiovascular diseases. Vascular endothelial cells form the vascular endothelium as a monolayer that covers the vascular lumen and serves as an interface between circulating blood and immune cells. Endothelial cells regulate vascular function in collaboration with smooth muscle cells. Endothelial dysfunction under pathophysiological conditions contributes to the development of vascular dysfunction. Here, we address the barrier function and microtubule function of endothelial cells. Endothelial barrier function, mediated by cell-to-cell junctions between endothelial cells, is regulated by small GTPases and kinases. Microtubule function, regulated by the acetylation of tubulin, a component of the microtubules, is a target of atherogenic stimuli. The elucidation of the molecular mechanisms of endothelial dysfunction as a cellular mechanism for vascular failure could provide novel therapeutic targets of cardiovascular diseases.
Collapse
Affiliation(s)
- Tetsuaki Hirase
- Department of Cardiovascular Medicine, Saga University, Saga, Japan
| | | |
Collapse
|
29
|
Skowrońska M, Albrecht J. Alterations of blood brain barrier function in hyperammonemia: an overview. Neurotox Res 2011; 21:236-44. [PMID: 21874372 PMCID: PMC3246587 DOI: 10.1007/s12640-011-9269-4] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 08/12/2011] [Accepted: 08/17/2011] [Indexed: 02/01/2023]
Abstract
Ammonia is a neurotoxin involved in the pathogenesis of neurological conditions associated with hyperammonemia, including hepatic encephalopathy, a condition associated with acute—(ALF) or chronic liver failure. This article reviews evidence that apart from directly affecting the metabolism and function of the central nervous system cells, ammonia influences the passage of different molecules across the blood brain barrier (BBB). A brief description is provided of the tight junctions, which couple adjacent cerebral capillary endothelial cells to each other to form the barrier. Ammonia modulates the transcellular passage of low-to medium-size molecules, by affecting their carriers located at the BBB. Ammonia induces interrelated aberrations of the transport of the large neutral amino acids and aromatic amino acids (AAA), whose influx is augmented by exchange with glutamine produced in the course of ammonia detoxification, and maybe also modulated by the extracellularly acting gamma-glutamyl moiety transferring enzyme, gamma-glutamyl-transpeptidase. Impaired AAA transport affects neurotransmission by altering intracerebral synthesis of catecholamines (serotonin and dopamine), and producing “false neurotransmitters” (octopamine and phenylethylamine). Ammonia also modulates BBB transport of the cationic amino acids: the nitric oxide precursor, arginine, and ornithine, which is an ammonia trap, and affects the transport of energy metabolites glucose and creatine. Moreover, ammonia acting either directly or in synergy with liver injury-derived inflammatory cytokines also evokes subtle increases of the transcellular passage of molecules of different size (BBB “leakage”), which appears to be responsible for the vasogenic component of cerebral edema associated with ALF.
Collapse
Affiliation(s)
- Marta Skowrońska
- Departament of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, 02-106 Warszawa, Pawińskiego 5, Poland
| | | |
Collapse
|
30
|
Toris GT, Bikis CN, Tsourouflis GS, Theocharis SE. Hepatic encephalopathy: an updated approach from pathogenesis to treatment. Med Sci Monit 2011; 17:RA53-63. [PMID: 21278704 PMCID: PMC3524698 DOI: 10.12659/msm.881387] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
One of the most serious complications of chronic or fulminant liver failure is hepatic encephalopathy (HE), associated most commonly with cirrhosis. In the presence of chronic liver disease, HE is a sign of decompensation, while in fulminant liver failure its development represents a worrying sign and usually indicates that transplantation will be required. Despite the significance of HE in the course of liver disease, the progress in development of new therapeutic options has been unremarkable over the last 20 years. An up-to-date review regarding HE, including both research and review articles. HE is a serious and progressive, but potentially reversible, disorder with a wide spectrum of neuropsychiatric abnormalities and motor disturbances that ranges from mild alteration of cognitive and motor function to coma and death. Although a clear pathogenesis is yet to be determined, elevated ammonia in serum and the central nervous system is the mainstay for pathogenesis and treatment of HE. Management includes early diagnosis and prompt treatment of precipitating factors. Clinical trials and extensive clinical experience have established the efficacy of diverse substances in HE treatment. Novel therapies with clinical promise include: L-ornithine L-aspartate, sodium benzoate, phenylacetate, AST-120, and the molecular adsorbent recirculating system. Eventually, liver transplantation is often the most successful long-term therapy for HE.
Collapse
Affiliation(s)
- Giannakis T Toris
- Department of Forensic Medicine and Toxicology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | | | | | | |
Collapse
|
31
|
Tachikawa M, Hosoya KI. Transport characteristics of guanidino compounds at the blood-brain barrier and blood-cerebrospinal fluid barrier: relevance to neural disorders. Fluids Barriers CNS 2011; 8:13. [PMID: 21352605 PMCID: PMC3058069 DOI: 10.1186/2045-8118-8-13] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Accepted: 02/28/2011] [Indexed: 12/24/2022] Open
Abstract
Guanidino compounds (GCs), such as creatine, phosphocreatine, guanidinoacetic acid, creatinine, methylguanidine, guanidinosuccinic acid, γ-guanidinobutyric acid, β-guanidinopropionic acid, guanidinoethane sulfonic acid and α-guanidinoglutaric acid, are present in the mammalian brain. Although creatine and phosphocreatine play important roles in energy homeostasis in the brain, accumulation of GCs may induce epileptic discharges and convulsions. This review focuses on how physiologically important and/or neurotoxic GCs are distributed in the brain under physiological and pathological conditions. Transporters for GCs at the blood-brain barrier (BBB) and the blood-cerebrospinal fluid (CSF) barrier (BCSFB) have emerged as substantial contributors to GCs distribution in the brain. Creatine transporter (CRT/solute carrier (SLC) 6A8) expressed at the BBB regulates creatine concentration in the brain, and represents a major pathway for supply of creatine from the circulating blood to the brain. CRT may be a key factor facilitating blood-to-brain guanidinoacetate transport in patients deficient in S-adenosylmethionine:guanidinoacetate N-methyltransferase, the creatine biosynthetic enzyme, resulting in cerebral accumulation of guanidinoacetate. CRT, taurine transporter (TauT/SLC6A6) and organic cation transporter (OCT3/SLC22A3) expressed at the BCSFB are involved in guanidinoacetic acid or creatinine efflux transport from CSF. Interestingly, BBB efflux transport of GCs, including guanidinoacetate and creatinine, is negligible, though the BBB has a variety of efflux transport systems for synthetic precursors of GCs, such as amino acids and neurotransmitters. Instead, the BCSFB functions as a major cerebral clearance system for GCs. In conclusion, transport of GCs at the BBB and BCSFB appears to be the key determinant of the cerebral levels of GCs, and changes in the transport characteristics may cause the abnormal distribution of GCs in the brain seen in patients with certain neurological disorders.
Collapse
Affiliation(s)
- Masanori Tachikawa
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan.
| | | |
Collapse
|
32
|
Abstract
Claudin-5 is a transmembrane tight junction protein highly expressed in brain endothelial cells, the site of the blood-brain barrier. The properties of the brain endothelial tight junction complex are considered to be dependent on claudin-5 cell-cell interaction, putting this protein in a position to play a major role in the maintenance of brain endothelial barrier integrity. Thus, alterations in claudin-5 function can lead to "opening" of the paracellular route and increased brain endothelial barrier permeability. Recent work from the authors's laboratory has established that caveolae-dependent internalization/recycling of claudin-5 is a mechanism underlying transient increases in brain endothelial paracellular permeability in the presence of pro-inflammatory mediators. The biochemical and microscopic techniques presented here were used to investigate trafficking of claudin-5 during those changes in paracellular permeability.
Collapse
|
33
|
Asaka M, Hirase T, Hashimoto-Komatsu A, Node K. Rab5a-mediated localization of claudin-1 is regulated by proteasomes in endothelial cells. Am J Physiol Cell Physiol 2010; 300:C87-96. [PMID: 20926780 DOI: 10.1152/ajpcell.00565.2010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tight junctions composed of transmembrane proteins, including claudin, occludin, and tricellulin, and peripheral membrane proteins are a major barrier to endothelial permeability, whereas the role of claudin in the regulation of tight junction permeability in nonneural endothelial cells is unclear. This study demonstrates that claudin-1 is dominantly expressed and depletion of claudin-1 using small interfering RNA (siRNA) increased tight junction permeability in EA hy.926 cells, indicating that claudin-1 is a crucial regulator of endothelial tight junction permeability. The ubiquitin-proteasome system has been implicated in the regulation of endocytotic trafficking of plasma membrane proteins. Therefore, the involvement of proteasomes in the localization of claudin-1 was investigated by pharmacological and genetic inhibition of proteasomes using a proteasome inhibitor, N-acetyl-Leu-Leu-Nle-CHO, and siRNA against the β₅-subunit of the 20S proteasome, respectively. Claudin-1 was localized at cell-cell contact sites in control cells. Claudin-1 was localized in the cytoplasm in association with Rab5a and EEA-1, a marker of early endosome, following inhibition of proteasomes. Depletion of Rab5a using siRNA reversed the localization of claudin-1 induced by inhibition of proteasomes. These data suggest that proteasomes regulate claudin-1 localization at the plasma membrane, which changes upon proteasomal inhibition to a Rab5a-mediated endosomal localization.
Collapse
Affiliation(s)
- Machiko Asaka
- Department of Cardiovascular and Renal Medicine, Saga University, Japan
| | | | | | | |
Collapse
|
34
|
Béard E, Braissant O. Synthesis and transport of creatine in the CNS: importance for cerebral functions. J Neurochem 2010; 115:297-313. [DOI: 10.1111/j.1471-4159.2010.06935.x] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
35
|
Stamatovic SM, Keep RF, Andjelkovic AV. Brain endothelial cell-cell junctions: how to "open" the blood brain barrier. Curr Neuropharmacol 2010; 6:179-92. [PMID: 19506719 PMCID: PMC2687937 DOI: 10.2174/157015908785777210] [Citation(s) in RCA: 351] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2007] [Revised: 03/10/2008] [Accepted: 04/02/2008] [Indexed: 01/19/2023] Open
Abstract
The blood-brain barrier (BBB) is a highly specialized structural and biochemical barrier that regulates the entry of blood-borne molecules into brain, and preserves ionic homeostasis within the brain microenvironment. BBB properties are primarily determined by junctional complexes between the cerebral endothelial cells. These complexes are comprised of tight and adherens junctions. Such restrictive angioarchitecture at the BBB reduces paracellular diffusion, while minimal vesicle transport activity in brain endothelial cells limits transcellular transport. Under normal conditions, this largely prevents the extravasation of large and small solutes (unless specific transporters are present) and prevents migration of any type of blood-borne cell. However, this is changed in many pathological conditions. There, BBB disruption (“opening”) can lead to increased paracellular permeability, allowing entry of leukocytes into brain tissue, but also contributing to edema formation. In parallel, there are changes in the endothelial pinocytotic vesicular system resulting in the uptake and transfer of fluid and macromolecules into brain parenchyma. This review highlights the route and possible factors involved in BBB disruption in a variety of neuropathological disorders (e.g. CNS inflammation, Alzheimer’s disease, Parkinson’s disease, epilepsy). It also summarizes proposed signal transduction pathways that may be involved in BBB “opening”.
Collapse
|
36
|
Cardoso FL, Brites D, Brito MA. Looking at the blood-brain barrier: molecular anatomy and possible investigation approaches. ACTA ACUST UNITED AC 2010; 64:328-63. [PMID: 20685221 DOI: 10.1016/j.brainresrev.2010.05.003] [Citation(s) in RCA: 389] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Revised: 05/18/2010] [Accepted: 05/19/2010] [Indexed: 12/17/2022]
Abstract
The blood-brain barrier (BBB) is a dynamic and complex interface between blood and the central nervous system that strictly controls the exchanges between the blood and brain compartments, therefore playing a key role in brain homeostasis and providing protection against many toxic compounds and pathogens. In this review, the unique properties of brain microvascular endothelial cells and intercellular junctions are examined. The specific interactions between endothelial cells and basement membrane as well as neighboring perivascular pericytes, glial cells and neurons, which altogether constitute the neurovascular unit and play an essential role in both health and function of the central nervous system, are also explored. Some relevant pathways across the endothelium, as well as mechanisms involved in the regulation of BBB permeability, and the emerging role of the BBB as a signaling interface are addressed as well. Furthermore, we summarize some of the experimental approaches that can be used to monitor BBB properties and function in a variety of conditions and have allowed recent advances in BBB knowledge. Elucidation of the molecular anatomy and dynamics of the BBB is an essential step for the development of new strategies directed to maintain or restore BBB integrity and barrier function and ultimately preserve the delicate interstitial brain environment.
Collapse
Affiliation(s)
- Filipa Lourenço Cardoso
- Research Institute for Medicines and Pharmaceutical Sciences (iMed.UL), Faculty of Pharmacy, University of Lisbon, Lisbon, Portugal
| | | | | |
Collapse
|
37
|
Braissant O. Ammonia toxicity to the brain: effects on creatine metabolism and transport and protective roles of creatine. Mol Genet Metab 2010; 100 Suppl 1:S53-8. [PMID: 20227315 DOI: 10.1016/j.ymgme.2010.02.011] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2009] [Accepted: 02/08/2010] [Indexed: 11/17/2022]
Abstract
Hyperammonemia can provoke irreversible damage to the developing brain, with the formation of cortical atrophy, ventricular enlargement, demyelination or gray and white matter hypodensities. Among the various pathogenic mechanisms involved, alterations in cerebral energy have been demonstrated. In particular, we could show that ammonia exposure generates a secondary deficiency in creatine in brain cells, by altering the brain expression and activity of the genes allowing creatine synthesis (AGAT and GAMT) and transport (SLC6A8). On the other hand, it is known that creatine administration can exert protective effects in various neurodegenerative processes. We could also show that creatine co-treatment under ammonia exposure can protect developing brain cells from some of the deleterious effects of ammonia, in particular axonal growth impairment. This article focuses on the effects of ammonia exposure on creatine metabolism and transport in developing brain cells, and on the potential neuroprotective properties of creatine in the brain exposed to ammonium.
Collapse
Affiliation(s)
- Olivier Braissant
- Inborn Errors of Metabolism, Clinical Chemistry Laboratory, Center Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland.
| |
Collapse
|
38
|
Yablonsky-Alter E, Agovic MS, Gashi E, Lidsky TI, Friedman E, Banerjee SP. Cocaine challenge enhances release of neuroprotective amino acid taurine in the striatum of chronic cocaine treated rats: a microdialysis study. Brain Res Bull 2009; 79:215-8. [PMID: 19166917 DOI: 10.1016/j.brainresbull.2008.12.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2008] [Accepted: 12/22/2008] [Indexed: 10/21/2022]
Abstract
Drug addiction is a serious public health problem. There is increasing evidence on the involvement of augmented glutamatergic transmission in cocaine-induced addiction and neurotoxicity. We investigated effects of acute or chronic cocaine administration and cocaine challenge following chronic cocaine exposure on the release of excitotoxic glutamate and neuroprotective taurine in the rat striatum by microdialysis. Cocaine challenge, following withdrawal after repeated cocaine exposure markedly increased the release of glutamate, which may cause neurotoxicity. Simultaneously, cocaine challenge after withdrawal also significantly increased the release of taurine, which counteracts glutamate-mediated excitotoxicity and possibly cell death. Thus, the mammalian brain has an endogenous self-protective mechanism against cocaine-mediated neurotoxicity and potentially addiction.
Collapse
Affiliation(s)
- Elena Yablonsky-Alter
- Department of Physiology and Pharmacology, The City University of New York, Medical School, New York, 10031, USA
| | | | | | | | | | | |
Collapse
|
39
|
Alterations in expression of genes coding for proteins of the neurovascular unit in ischemic liver failure. Neurochem Int 2009; 55:119-23. [DOI: 10.1016/j.neuint.2009.01.023] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Revised: 01/26/2009] [Accepted: 01/27/2009] [Indexed: 01/20/2023]
|
40
|
Braissant O, Cagnon L, Monnet-Tschudi F, Speer O, Wallimann T, Honegger P, Henry H. Ammonium alters creatine transport and synthesis in a 3D culture of developing brain cells, resulting in secondary cerebral creatine deficiency. Eur J Neurosci 2008; 27:1673-85. [DOI: 10.1111/j.1460-9568.2008.06126.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
41
|
Abstract
A class of endogenous opioids is upregulated in liver disease particular to cholestasis, which contributes to symptoms in liver disease such as pruritus, hypotension and encephalopathy. Symptoms associated with cholestasis are reversed or at least ameliorated by mu opioid receptor antagonists. Palliation of symptoms related to cholestatic liver disease also involves bile acid binding agents. Opioid receptor antagonists, unlike bile acid binding agents, have been reported to relieve multiple symptoms, except for pruritus, and improve liver function as demonstrated in experimental cholestasis. Exogenous opioid pharmacology is altered by liver disease. Dose reduction or prolongation of dose intervals is necessary depending on the severity of liver disease.
Collapse
Affiliation(s)
- Mellar Davis
- The Harry R Horvitz Center for Palliative Medicine, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
| |
Collapse
|
42
|
Konopacka A, Zielińska M, Albrecht J. Ammonia inhibits the C-type natriuretic peptide-dependent cyclic GMP synthesis and calcium accumulation in a rat brain endothelial cell line. Neurochem Int 2007; 52:1160-6. [PMID: 18222015 DOI: 10.1016/j.neuint.2007.12.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2007] [Revised: 11/28/2007] [Accepted: 12/09/2007] [Indexed: 01/30/2023]
Abstract
Recently we reported a decrease of C-type natriuretic peptide (CNP)-dependent, natriuretic peptide receptor 2 (NPR2)-mediated cyclic GMP (cGMP) synthesis in a non-neuronal compartment of cerebral cortical slices of hyperammonemic rats [Zielińska, M., Fresko, I., Konopacka, A., Felipo, V., Albrecht, J., 2007. Hyperammonemia inhibits the natriuretic peptide receptor 2 (NPR2)-mediated cyclic GMP synthesis in the astrocytic compartment of rat cerebral cortex slices. Neurotoxicology 28, 1260-1263]. Here we accounted for the possible involvement of cerebral capillary endothelial cells in this response by measuring the effect of ammonia on the CNP-mediated cGMP formation and intracellular calcium ([Ca2+]i) accumulation in a rat cerebral endothelial cell line (RBE-4). We first established that stimulation of cGMP synthesis in RBE-4 cells was coupled to protein kinase G (PKG)-mediated Ca2+ influx from the medium which was inhibited by an L-type channel blocker nimodipine. Ammonia treatment (1h, 5mM NH4Cl) evoked a substantial decrease of CNP-stimulated cGMP synthesis which was related to a decreased binding of CNP to NPR2 receptors, and depressed the CNP-dependent [Ca2+]i accumulation in these cells. Ammonia also abolished the CNP-dependent Ca2+ accumulation in the absence of Na+. In cells incubated with ammonia in the absence of Ca2+ a slight CNP-dependent increase of [Ca2+]i was observed, most likely representing Ca2+ release from intracellular stores. Depression of CNP-dependent cGMP-mediated [Ca2+]i accumulation may contribute to cerebral vascular endothelial dysfunction associated with hyperammonemia or hepatic encephalopathy.
Collapse
Affiliation(s)
- Agnieszka Konopacka
- Department of Neurotoxicology, Medical Research Centre, Polish Academy of Sciences, Pawińskiego 5, 02-106 Warsaw, Poland
| | | | | |
Collapse
|
43
|
Wyss M, Braissant O, Pischel I, Salomons GS, Schulze A, Stockler S, Wallimann T. Creatine and creatine kinase in health and disease--a bright future ahead? Subcell Biochem 2007; 46:309-34. [PMID: 18652084 DOI: 10.1007/978-1-4020-6486-9_16] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Many links are reported or suspected between the functioning of creatine, phosphocreatine, the creatine kinase isoenzymes or the creatine biosynthesis enzymes on one hand, and health or disease on the other hand. The aim of the present book was to outline our current understanding on many of these links. In this chapter, we summarize the main messages and conclusions presented in this book. In addition, we refer to a number of recent publications that highlight the pleiotropy in physiological functions of creatine and creatine kinase, and which suggest that numerous discoveries on new functions of this system are still ahead of us. Finally, we present our views on the most promising future avenues of research to deepen our knowledge on creatine and creatine kinase. In particular, we elaborate on how state-of-the-art high-throughput analytical ("omics") technologies and systems biology approaches may be used successfully to unravel the complex network of interdependent physiological functions related to creatine and creatine kinase.
Collapse
Affiliation(s)
- Markus Wyss
- DSM Nutritional Products Ltd., Biotechnology R&D, Bldg. 203/17B, P.O. Box 3255, CH-4002 Basel, Switzerland
| | | | | | | | | | | | | |
Collapse
|
44
|
Ma YP, Ma MM, Ge S, Guo RB, Zhang HJ, Frey WH, Xu GL, Liu XF. Intranasally delivered TGF-beta1 enters brain and regulates gene expressions of its receptors in rats. Brain Res Bull 2007; 74:271-7. [PMID: 17720549 DOI: 10.1016/j.brainresbull.2007.06.021] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2007] [Revised: 06/25/2007] [Accepted: 06/28/2007] [Indexed: 02/02/2023]
Abstract
This study is aimed to evaluate the brain distribution of transforming growth factor-beta1 (TGF-beta1) following intranasal administration and the subsequent biological effects of TGF-beta1. Adult rats were given recombinant human TGF-beta1 (rhTGF-beta1) or vehicle solution intranasally. TGF-beta1 concentrations were significantly raised in several brain regions and the trigeminal nerve following intranasal delivery. The elevation appeared within 30 min and was sustained for at least 6 h, reaching its greatest level at 60 min. A concentration gradient in the central nervous system (CNS) regions was produced during the first 2 h after intranasal administration, with the OB presenting a significantly higher concentration than any other CNS regions. The nasally administered TGF-beta1 subsequently regulated gene expressions of its two receptors (TGF-beta receptor types I and II) in vivo, but did not affect mRNA level of TGF-beta1 itself. Our results suggest that TGF-beta1 can be transported into the CNS via the olfactory and trigeminal pathways, and may consequently exert its biological effects by regulating gene expressions of its receptors. Intranasal administration of neurotrophic factors may offer a potential strategy for treating some CNS disorders.
Collapse
Affiliation(s)
- Yu-Ping Ma
- Department of Neurology, Jinling Hospital, Nanjing University School of Medicine, 305# East Zhongshan Road, Nanjing 210002, Jiangsu Province, People's Republic of China
| | | | | | | | | | | | | | | |
Collapse
|
45
|
Tachikawa M, Hosoya KI, Ohtsuki S, Terasaki T. A novel relationship between creatine transport at the blood-brain and blood-retinal barriers, creatine biosynthesis, and its use for brain and retinal energy homeostasis. Subcell Biochem 2007; 46:83-98. [PMID: 18652073 DOI: 10.1007/978-1-4020-6486-9_5] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Evidence is increasing that the creatine/phosphocreatine shuttle system plays an essential role in energy homeostasis in the brain and retina to ensure proper development and function. Thus, our understanding of the mechanism of creatine supply and creatine usage in the brain and retina and of creatine supplementation in patients with creatine deficiency syndromes is an important step towards improved therapeutic strategies for brain and retinal disorders. Our recent research provides novel molecular-anatomical evidence that (i) at the blood-brain barrier and the inner blood-retinal barrier, the creatine transporter (CRT/SLC6AS) functions as a major pathway for supplying creatine to the brain and retina, and that (ii) local creatine is preferentially synthesized in the glial cells, e.g., oligodendrocytes, astrocytes, and Müller cells, in the brain and retina. Thus, the blood-brain barrier and inner blood-retinal barrier play important roles not only in supplying energy sources (glucose and lactate), but also in supplying an energy 'buffer' (creatine). These findings lead to the novel insight that the creatine/phosphocreatine shuttle system is based on an intricate relationship between the blood-brain barrier, inner blood-retinal barrier, glia, and neurons (photoreceptor cells) to maintain and ensure energy homeostasis in the brain and retina.
Collapse
Affiliation(s)
- Masanori Tachikawa
- Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama 930-0194, Japan
| | | | | | | |
Collapse
|