1
|
Grønbæk-Thygesen M, Hartmann-Petersen R. Cellular and molecular mechanisms of aspartoacylase and its role in Canavan disease. Cell Biosci 2024; 14:45. [PMID: 38582917 PMCID: PMC10998430 DOI: 10.1186/s13578-024-01224-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 03/24/2024] [Indexed: 04/08/2024] Open
Abstract
Canavan disease is an autosomal recessive and lethal neurological disorder, characterized by the spongy degeneration of the white matter in the brain. The disease is caused by a deficiency of the cytosolic aspartoacylase (ASPA) enzyme, which catalyzes the hydrolysis of N-acetyl-aspartate (NAA), an abundant brain metabolite, into aspartate and acetate. On the physiological level, the mechanism of pathogenicity remains somewhat obscure, with multiple, not mutually exclusive, suggested hypotheses. At the molecular level, recent studies have shown that most disease linked ASPA gene variants lead to a structural destabilization and subsequent proteasomal degradation of the ASPA protein variants, and accordingly Canavan disease should in general be considered a protein misfolding disorder. Here, we comprehensively summarize the molecular and cell biology of ASPA, with a particular focus on disease-linked gene variants and the pathophysiology of Canavan disease. We highlight the importance of high-throughput technologies and computational prediction tools for making genotype-phenotype predictions as we await the results of ongoing trials with gene therapy for Canavan disease.
Collapse
Affiliation(s)
- Martin Grønbæk-Thygesen
- The Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, 2200N, Copenhagen, Denmark.
| | - Rasmus Hartmann-Petersen
- The Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, 2200N, Copenhagen, Denmark.
| |
Collapse
|
2
|
Cheng H, Miller D, Southwell N, Fischer JL, Taylor I, Salbaum JM, Kappen C, Hu F, Yang C, Gross SS, D'Aurelio M, Chen Q. Untargeted Pixel-by-Pixel Imaging of Metabolite Ratio Pairs as a Novel Tool for Biomedical Discovery in Mass Spectrometry Imaging. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.10.575105. [PMID: 38370710 PMCID: PMC10871215 DOI: 10.1101/2024.01.10.575105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Mass spectrometry imaging (MSI) is a powerful technology used to define the spatial distribution and relative abundance of structurally identified and yet-undefined metabolites across tissue cryosections. While numerous software packages enable pixel-by-pixel imaging of individual metabolites, the research community lacks a discovery tool that images all metabolite abundance ratio pairs. Importantly, recognition of correlated metabolite pairs informs discovery of unanticipated molecules contributing to shared metabolic pathways, uncovers hidden metabolic heterogeneity across cells and tissue subregions, and indicates single-timepoint flux through pathways of interest. Here, we describe the development and implementation of an untargeted R package workflow for pixel-by-pixel ratio imaging of all metabolites detected in an MSI experiment. Considering untargeted MSI studies of murine brain and embryogenesis, we demonstrate that ratio imaging minimizes systematic data variation introduced by sample handling and instrument drift, markedly enhances spatial image resolution, and reveals previously unrecognized metabotype-distinct tissue regions. Furthermore, ratio imaging facilitates identification of novel regional biomarkers and provides anatomical information regarding spatial distribution of metabolite-linked biochemical pathways. The algorithm described herein is applicable to any MSI dataset containing spatial information for metabolites, peptides or proteins, offering a potent tool to enhance knowledge obtained from current spatial metabolite profiling technologies.
Collapse
|
3
|
Francis JS, Nguyen Q, Markov V, Leone P. Over-expression of N-acetylaspartate synthase exacerbates pathological energetic deficit and accelerates cognitive decline in the 5xFAD mouse. J Neurochem 2024; 168:69-82. [PMID: 38178803 DOI: 10.1111/jnc.16044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 12/19/2023] [Accepted: 12/20/2023] [Indexed: 01/06/2024]
Abstract
N-acetylaspartate (NAA) is an abundant central nervous system amino acid derivative that is tightly coupled to mitochondria and energy metabolism in neurons. A reduced NAA signature is a prominent early pathological biomarker in multiple neurodegenerative diseases and becomes progressively more pronounced as disease advances. Because NAA synthesis requires aspartate drawn directly from mitochondria, we argued that this process is in direct competition with oxidative phosphorylation for substrate and that sustained high levels of NAA synthesis would be incompatible with pathological energy crisis. We show here that over-expression of the rate-limiting NAA synthetic enzyme in the hippocampus of the 5x familial Alzheimer's disease (5xFAD) mouse results in an exaggerated pathological ATP deficit and accelerated cognitive decline. Over-expression of NAA synthase did not increase amyloid burden or result in cell loss but did significantly deplete mitochondrial aspartate and impair the ability of mitochondria to oxidize glutamate for adenosine triphosphate (ATP) synthesis. These results define NAA as a sink for energetic substrate and suggest initial pathological reductions in NAA are part of a response to energetic crisis designed to preserve substrate bioavailability for mitochondrial ATP synthesis.
Collapse
Affiliation(s)
- Jeremy S Francis
- Cell & Gene Therapy Center, Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine, Stratford, New Jersey, USA
| | - Quy Nguyen
- Cell & Gene Therapy Center, Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine, Stratford, New Jersey, USA
| | - Vladimir Markov
- Cell & Gene Therapy Center, Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine, Stratford, New Jersey, USA
| | - Paola Leone
- Cell & Gene Therapy Center, Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine, Stratford, New Jersey, USA
| |
Collapse
|
4
|
Taheri M, Pourtavakoli A, Eslami S, Ghafouri-Fard S, Sayad A. Assessment of expression of calcium signaling related lncRNAs in epilepsy. Sci Rep 2023; 13:17993. [PMID: 37865723 PMCID: PMC10590428 DOI: 10.1038/s41598-023-45341-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 10/18/2023] [Indexed: 10/23/2023] Open
Abstract
Calcium signaling is a metabolic pathway that is essential in neurons development and can be involved in the pathobiology of epilepsy. We assessed expression of three mRNA coding gene (SLC1A1, SLC25A12, and ATP2B2) and three related long non-coding RNAs (LINC01231:1, lnc-SLC25A12-8:1 and lnc-MTR-1:1) from this pathway in 39 patients with refractory epilepsy and 71 healthy controls. Expression of all genes except for lnc-SLC25A12 was higher in total epileptic cases compared with controls (P values = 0.0002, < 0.0001, < 0.0001, 0.049 and 0.0005 for SLC1A1, SLC25A12, LINC01231, ATP2B2 and lnc-MTR-1, respectively. When we separately compared expression of genes among males and females, SLC1A1, SLC25A12, LINC01231 and lnc-MTR-1 showed up-regulation in male cases compared with male controls. Moreover, expressions of SLC1A1 and SLC25A12 were higher in female cases compared with female controls. Remarkably, SLC25A12 was found to have the highest sensitivity value (= 1) for differentiation of epileptic cases from controls. Moreover, lnc-MTR-1 and lnc-SLC25A12 were sensitive markers for such purpose (sensitivity values = 0.89 and 0.87, respectively). The highest value belonged to LINC01231 with the value of 0.76. Taken together, this study demonstrates dysregulation of calcium-signaling related genes in epileptic patients and suggests these genes as potential biomarkers for epilepsy.
Collapse
Affiliation(s)
- Mohammad Taheri
- Institute of Human Genetics, Jena University Hospital, Jena, Germany
- Urology and Nephrology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ashkan Pourtavakoli
- Genomic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Solat Eslami
- Dietary Supplements and Probiotic Research Center, Alborz University of Medical Sciences, Karaj, Iran
- Department of Medical Biotechnology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran
| | - Soudeh Ghafouri-Fard
- Department of Medical Genetics, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Arezou Sayad
- Genomic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
5
|
González-Moreno L, Santamaría-Cano A, Paradela A, Martínez-Chantar ML, Martín MÁ, Pérez-Carreras M, García-Picazo A, Vázquez J, Calvo E, González-Aseguinolaza G, Saheki T, del Arco A, Satrústegui J, Contreras L. Exogenous aralar/slc25a12 can replace citrin/slc25a13 as malate aspartate shuttle component in liver. Mol Genet Metab Rep 2023; 35:100967. [PMID: 36967723 PMCID: PMC10031141 DOI: 10.1016/j.ymgmr.2023.100967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 03/10/2023] [Indexed: 03/18/2023] Open
Abstract
The deficiency of CITRIN, the liver mitochondrial aspartate-glutamate carrier (AGC), is the cause of four human clinical phenotypes, neonatal intrahepatic cholestasis caused by CITRIN deficiency (NICCD), silent period, failure to thrive and dyslipidemia caused by CITRIN deficiency (FTTDCD), and citrullinemia type II (CTLN2). Clinical symptoms can be traced back to disruption of the malate-aspartate shuttle due to the lack of citrin. A potential therapy for this condition is the expression of aralar, the AGC present in brain, to replace citrin. To explore this possibility we have first verified that the NADH/NAD+ ratio increases in hepatocytes from citrin(-/-) mice, and then found that exogenous aralar expression reversed the increase in NADH/NAD+ observed in these cells. Liver mitochondria from citrin (-/-) mice expressing liver specific transgenic aralar had a small (~ 4-6 nmoles x mg prot-1 x min-1) but consistent increase in malate aspartate shuttle (MAS) activity over that of citrin(-/-) mice. These results support the functional replacement between AGCs in the liver. To explore the significance of AGC replacement in human therapy we studied the relative levels of citrin and aralar in mouse and human liver through absolute quantification proteomics. We report that mouse liver has relatively high aralar levels (citrin/aralar molar ratio of 7.8), whereas human liver is virtually devoid of aralar (CITRIN/ARALAR ratio of 397). This large difference in endogenous aralar levels partly explains the high residual MAS activity in liver of citrin(-/-) mice and why they fail to recapitulate the human disease, but supports the benefit of increasing aralar expression to improve the redox balance capacity of human liver, as an effective therapy for CITRIN deficiency.
Collapse
|
6
|
Gan Y, Wei Z, Liu C, Li G, Feng Y, Deng Y. Solute carrier transporter disease and developmental and epileptic encephalopathy. Front Neurol 2022; 13:1013903. [PMID: 36419532 PMCID: PMC9676364 DOI: 10.3389/fneur.2022.1013903] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 09/07/2022] [Indexed: 09/14/2023] Open
Abstract
The International League Against Epilepsy officially revised its classification in 2017, which amended "epileptic encephalopathy" to "developmental and epileptic encephalopathy". With the development of genetic testing technology, an increasing number of genes that cause developmental and epileptic encephalopathies are being identified. Among these, solute transporter dysfunction is part of the etiology of developmental and epileptic encephalopathies. Solute carrier transporters play an essential physiological function in the human body, and their dysfunction is associated with various human diseases. Therefore, in-depth studies of developmental and epileptic encephalopathies caused by solute carrier transporter dysfunction can help develop new therapeutic modalities to facilitate the treatment of refractory epilepsy and improve patient prognosis. In this article, the concept of transporter protein disorders is first proposed, and nine developmental and epileptic encephalopathies caused by solute carrier transporter dysfunction are described in detail in terms of pathogenesis, clinical manifestations, ancillary tests, and precise treatment to provide ideas for the precise treatment of epilepsy.
Collapse
Affiliation(s)
- Yajing Gan
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Zihan Wei
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Chao Liu
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Guoyan Li
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Yan Feng
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Yanchun Deng
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
- Xijing Institute of Epilepsy and Encephalopathy, Xi'an, China
| |
Collapse
|
7
|
Ketogenic Diet Treatment of Defects in the Mitochondrial Malate Aspartate Shuttle and Pyruvate Carrier. Nutrients 2022; 14:nu14173605. [PMID: 36079864 PMCID: PMC9460686 DOI: 10.3390/nu14173605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/10/2022] [Accepted: 08/15/2022] [Indexed: 11/17/2022] Open
Abstract
The mitochondrial malate aspartate shuttle system (MAS) maintains the cytosolic NAD+/NADH redox balance, thereby sustaining cytosolic redox-dependent pathways, such as glycolysis and serine biosynthesis. Human disease has been associated with defects in four MAS-proteins (encoded by MDH1, MDH2, GOT2, SLC25A12) sharing a neurological/epileptic phenotype, as well as citrin deficiency (SLC25A13) with a complex hepatopathic-neuropsychiatric phenotype. Ketogenic diets (KD) are high-fat/low-carbohydrate diets, which decrease glycolysis thus bypassing the mentioned defects. The same holds for mitochondrial pyruvate carrier (MPC) 1 deficiency, which also presents neurological deficits. We here describe 40 (18 previously unreported) subjects with MAS-/MPC1-defects (32 neurological phenotypes, eight citrin deficiency), describe and discuss their phenotypes and genotypes (presenting 12 novel variants), and the efficacy of KD. Of 13 MAS/MPC1-individuals with a neurological phenotype treated with KD, 11 experienced benefits—mainly a striking effect against seizures. Two individuals with citrin deficiency deceased before the correct diagnosis was established, presumably due to high-carbohydrate treatment. Six citrin-deficient individuals received a carbohydrate-restricted/fat-enriched diet and showed normalisation of laboratory values/hepatopathy as well as age-adequate thriving. We conclude that patients with MAS-/MPC1-defects are amenable to dietary intervention and that early (genetic) diagnosis is key for initiation of proper treatment and can even be lifesaving.
Collapse
|
8
|
Tavoulari S, Lacabanne D, Thangaratnarajah C, Kunji ERS. Pathogenic variants of the mitochondrial aspartate/glutamate carrier causing citrin deficiency. Trends Endocrinol Metab 2022; 33:539-553. [PMID: 35725541 PMCID: PMC7614230 DOI: 10.1016/j.tem.2022.05.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/26/2022] [Accepted: 05/19/2022] [Indexed: 12/22/2022]
Abstract
Citrin deficiency is a pan-ethnic and highly prevalent mitochondrial disease with three different stages: neonatal intrahepatic cholestasis (NICCD), a relatively mild adaptation stage, and type II citrullinemia in adulthood (CTLN2). The cause is the absence or dysfunction of the calcium-regulated mitochondrial aspartate/glutamate carrier 2 (AGC2/SLC25A13), also called citrin, which imports glutamate into the mitochondrial matrix and exports aspartate to the cytosol. In citrin deficiency, these missing transport steps lead to impairment of the malate-aspartate shuttle, gluconeogenesis, amino acid homeostasis, and the urea cycle. In this review, we describe the geological spread and occurrence of citrin deficiency, the metabolic consequences and use our current knowledge of the structure to predict the impact of the known pathogenic mutations on the calcium-regulatory and transport mechanism of citrin.
Collapse
Affiliation(s)
- Sotiria Tavoulari
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Denis Lacabanne
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Chancievan Thangaratnarajah
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Edmund R S Kunji
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK.
| |
Collapse
|
9
|
SLC25A12 Missense Variant in Nova Scotia Duck Tolling Retrievers Affected by Cerebellar Degeneration-Myositis Complex (CDMC). Genes (Basel) 2022; 13:genes13071223. [PMID: 35886006 PMCID: PMC9319113 DOI: 10.3390/genes13071223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/06/2022] [Accepted: 07/07/2022] [Indexed: 11/17/2022] Open
Abstract
We investigated two litters of distantly related Nova Scotia Duck Tolling Retrievers (NSDTR), of which four puppies were affected by cerebellar signs with or without neuromuscular weakness. The phenotype was termed cerebellar degeneration—myositis complex (CDMC). We suspected a heritable condition and initiated a genetic analysis. The genome of one affected dog was sequenced and compared to 565 control genomes. This search yielded a private protein-changing SLC25A12 variant in the affected dog, XM_038584842.1:c.1337C>T, predicted to result in the amino acid change XP_038440770.1:(p.Pro446Leu). The genotypes at the variant co-segregated with the phenotype as expected for a monogenic autosomal recessive mode of inheritance in both litters. Genotyping of 533 additional NSDTR revealed variant allele frequencies of 3.6% and 1.3% in a European and a North American cohort, respectively. The available clinical and biochemical data, together with current knowledge about SLC25A12 variants and their functional impact in humans, mice, and dogs, suggest the p.Pro446Leu variant is a candidate causative defect for the observed phenotype in the affected dogs.
Collapse
|
10
|
Pérez-Liébana I, Juaristi I, González-Sánchez P, González-Moreno L, Rial E, Podunavac M, Zakarian A, Molgó J, Vallejo-Illarramendi A, Mosqueira-Martín L, Lopez de Munain A, Pardo B, Satrústegui J, Del Arco A. A Ca 2+-Dependent Mechanism Boosting Glycolysis and OXPHOS by Activating Aralar-Malate-Aspartate Shuttle, upon Neuronal Stimulation. J Neurosci 2022; 42:3879-3895. [PMID: 35387872 PMCID: PMC9097769 DOI: 10.1523/jneurosci.1463-21.2022] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 12/20/2021] [Accepted: 01/27/2022] [Indexed: 01/18/2023] Open
Abstract
Calcium is an important second messenger regulating a bioenergetic response to the workloads triggered by neuronal activation. In embryonic mouse cortical neurons using glucose as only fuel, activation by NMDA elicits a strong workload (ATP demand)-dependent on Na+ and Ca2+ entry, and stimulates glucose uptake, glycolysis, pyruvate and lactate production, and oxidative phosphorylation (OXPHOS) in a Ca2+-dependent way. We find that Ca2+ upregulation of glycolysis, pyruvate levels, and respiration, but not glucose uptake, all depend on Aralar/AGC1/Slc25a12, the mitochondrial aspartate-glutamate carrier, component of the malate-aspartate shuttle (MAS). MAS activation increases glycolysis, pyruvate production, and respiration, a process inhibited in the presence of BAPTA-AM, suggesting that the Ca2+ binding motifs in Aralar may be involved in the activation. Mitochondrial calcium uniporter (MCU) silencing had no effect, indicating that none of these processes required MCU-dependent mitochondrial Ca2+ uptake. The neuronal respiratory response to carbachol was also dependent on Aralar, but not on MCU. We find that mouse cortical neurons are endowed with a constitutive ER-to-mitochondria Ca2+ flow maintaining basal cell bioenergetics in which ryanodine receptors, RyR2, rather than InsP3R, are responsible for Ca2+ release, and in which MCU does not participate. The results reveal that, in neurons using glucose, MCU does not participate in OXPHOS regulation under basal or stimulated conditions, while Aralar-MAS appears as the major Ca2+-dependent pathway tuning simultaneously glycolysis and OXPHOS to neuronal activation.SIGNIFICANCE STATEMENT Neuronal activation increases cell workload to restore ion gradients altered by activation. Ca2+ is involved in matching increased workload with ATP production, but the mechanisms are still unknown. We find that glycolysis, pyruvate production, and neuronal respiration are stimulated on neuronal activation in a Ca2+-dependent way, independently of effects of Ca2+ as workload inducer. Mitochondrial calcium uniporter (MCU) does not play a relevant role in Ca2+ stimulated pyruvate production and oxygen consumption as both are unchanged in MCU silenced neurons. However, Ca2+ stimulation is blunt in the absence of Aralar, a Ca2+-binding mitochondrial carrier component of Malate-Aspartate Shuttle (MAS). The results suggest that Ca2+-regulated Aralar-MAS activation upregulates glycolysis and pyruvate production, which fuels mitochondrial respiration, through regulation of cytosolic NAD+/NADH ratio.
Collapse
Affiliation(s)
- Irene Pérez-Liébana
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
| | - Inés Juaristi
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
| | - Paloma González-Sánchez
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
| | - Luis González-Moreno
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
| | - Eduardo Rial
- Department of Structural and Chemical Biology, Centro de Investigaciones Biológicas Margarita Salas, Madrid, 28040, Spain
| | - Maša Podunavac
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106
| | - Jordi Molgó
- Université Paris-Saclay, CEA, Institut des Sciences du Vivant Frédéric Joliot, ERL Centre National de la Recherche Scientifique no. 9004, Département Médicaments et Technologies pour la Santé, Service d'Ingénierie Moléculaire pour la Santé, Gif sur Yvette, F-91191, France
| | - Ainara Vallejo-Illarramendi
- IIS Biodonostia-University of the Basque Country, Donostia, Spain; CIBERNED (institute Carlos III), Madrid, Spain; and Department of Neurology, Hospital Universitario Donostia-OSAKIDETZA, San Sebastián, 20014, Spain
| | - Laura Mosqueira-Martín
- IIS Biodonostia-University of the Basque Country, Donostia, Spain; CIBERNED (institute Carlos III), Madrid, Spain; and Department of Neurology, Hospital Universitario Donostia-OSAKIDETZA, San Sebastián, 20014, Spain
| | - Adolfo Lopez de Munain
- IIS Biodonostia-University of the Basque Country, Donostia, Spain; CIBERNED (institute Carlos III), Madrid, Spain; and Department of Neurology, Hospital Universitario Donostia-OSAKIDETZA, San Sebastián, 20014, Spain
| | - Beatriz Pardo
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
| | - Jorgina Satrústegui
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
| | - Araceli Del Arco
- Departamento de Biología Molecular, Instituto Universitario de Biología Molecular -IUBM, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain; and Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Madrid, 28049, Spain
- Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla la Mancha, Toledo, 45071 Spain; and Centro Regional de Investigaciones Biomédicas, Unidad Asociada de Biomedicina, Toledo, 45071, Spain
| |
Collapse
|
11
|
Abstract
Mitochondria of all tissues convert various metabolic substrates into two forms of energy: ATP and heat. Historically, the primary focus of research in mitochondrial bioenergetics was on the mechanisms of ATP production, while mitochondrial thermogenesis received significantly less attention. Nevertheless, mitochondrial heat production is crucial for the maintenance of body temperature, regulation of the pace of metabolism, and prevention of oxidative damage to mitochondria and the cell. In addition, mitochondrial thermogenesis has gained significance as a pharmacological target for treating metabolic disorders. Mitochondria produce heat as the result of H+ leak across their inner membrane. This review provides a critical assessment of the current field of mitochondrial H+ leak and thermogenesis, with a focus on the molecular mechanisms involved in the function and regulation of uncoupling protein 1 and the ADP/ATP carrier, the two proteins that mediate mitochondrial H+ leak.
Collapse
Affiliation(s)
- Ambre M. Bertholet
- Department of Physiology, University of California San Francisco, 600 16 Street, San Francisco, CA 94158, USA,Department of Physiology, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, Los Angeles, CA 90095, USA,Corresponding authors: ,
| | - Yuriy Kirichok
- Department of Physiology, University of California, San Francisco, California, USA;
| |
Collapse
|
12
|
Pardo B, Herrada-Soler E, Satrústegui J, Contreras L, del Arco A. AGC1 Deficiency: Pathology and Molecular and Cellular Mechanisms of the Disease. Int J Mol Sci 2022; 23:528. [PMID: 35008954 PMCID: PMC8745132 DOI: 10.3390/ijms23010528] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/23/2021] [Accepted: 12/24/2021] [Indexed: 02/01/2023] Open
Abstract
AGC1/Aralar/Slc25a12 is the mitochondrial carrier of aspartate-glutamate, the regulatory component of the NADH malate-aspartate shuttle (MAS) that transfers cytosolic redox power to neuronal mitochondria. The deficiency in AGC1/Aralar leads to the human rare disease named "early infantile epileptic encephalopathy 39" (EIEE 39, OMIM # 612949) characterized by epilepsy, hypotonia, arrested psychomotor neurodevelopment, hypo myelination and a drastic drop in brain aspartate (Asp) and N-acetylaspartate (NAA). Current evidence suggest that neurons are the main brain cell type expressing Aralar. However, paradoxically, glial functions such as myelin and Glutamine (Gln) synthesis are markedly impaired in AGC1 deficiency. Herein, we discuss the role of the AGC1/Aralar-MAS pathway in neuronal functions such as Asp and NAA synthesis, lactate use, respiration on glucose, glutamate (Glu) oxidation and other neurometabolic aspects. The possible mechanism triggering the pathophysiological findings in AGC1 deficiency, such as epilepsy and postnatal hypomyelination observed in humans and mice, are also included. Many of these mechanisms arise from findings in the aralar-KO mice model that extensively recapitulate the human disease including the astroglial failure to synthesize Gln and the dopamine (DA) mishandling in the nigrostriatal system. Epilepsy and DA mishandling are a direct consequence of the metabolic defect in neurons due to AGC1/Aralar deficiency. However, the deficits in myelin and Gln synthesis may be a consequence of neuronal affectation or a direct effect of AGC1/Aralar deficiency in glial cells. Further research is needed to clarify this question and delineate the transcellular metabolic fluxes that control brain functions. Finally, we discuss therapeutic approaches successfully used in AGC1-deficient patients and mice.
Collapse
Affiliation(s)
- Beatriz Pardo
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain; (E.H.-S.); (J.S.); (L.C.)
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid (UAM)-Consejo Superior de Investigaciones Científicas (CSIC), 28049 Madrid, Spain;
- Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Eduardo Herrada-Soler
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain; (E.H.-S.); (J.S.); (L.C.)
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid (UAM)-Consejo Superior de Investigaciones Científicas (CSIC), 28049 Madrid, Spain;
- Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Jorgina Satrústegui
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain; (E.H.-S.); (J.S.); (L.C.)
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid (UAM)-Consejo Superior de Investigaciones Científicas (CSIC), 28049 Madrid, Spain;
- Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Laura Contreras
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid, Spain; (E.H.-S.); (J.S.); (L.C.)
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid (UAM)-Consejo Superior de Investigaciones Científicas (CSIC), 28049 Madrid, Spain;
- Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Araceli del Arco
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid (UAM)-Consejo Superior de Investigaciones Científicas (CSIC), 28049 Madrid, Spain;
- Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Centro Regional de Investigaciones Biomédicas, Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla La Mancha, 45071 Toledo, Spain
| |
Collapse
|
13
|
Role of Energy Metabolism in the Progression of Neuroblastoma. Int J Mol Sci 2021; 22:ijms222111421. [PMID: 34768850 PMCID: PMC8583976 DOI: 10.3390/ijms222111421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Revised: 10/17/2021] [Accepted: 10/21/2021] [Indexed: 12/16/2022] Open
Abstract
Neuroblastoma is a common childhood cancer possessing a significant risk of death. This solid tumor manifests variable clinical behaviors ranging from spontaneous regression to widespread metastatic disease. The lack of promising treatments calls for new research approaches which can enhance the understanding of the molecular background of neuroblastoma. The high proliferation of malignant neuroblastoma cells requires efficient energy metabolism. Thus, we focus our attention on energy pathways and their role in neuroblastoma tumorigenesis. Recent studies suggest that neuroblastoma-driven extracellular vesicles stimulate tumorigenesis inside the recipient cells. Furthermore, proteomic studies have demonstrated extracellular vesicles (EVs) to cargo metabolic enzymes needed to build up a fully operative energy metabolism network. The majority of EV-derived enzymes comes from glycolysis, while other metabolic enzymes have a fatty acid β-oxidation and tricarboxylic acid cycle origin. The previously mentioned glycolysis has been shown to play a primary role in neuroblastoma energy metabolism. Therefore, another way to modify the energy metabolism in neuroblastoma is linked with genetic alterations resulting in the decreased activity of some tricarboxylic acid cycle enzymes and enhanced glycolysis. This metabolic shift enables malignant cells to cope with increasing metabolic stress, nutrition breakdown and an upregulated proliferation ratio.
Collapse
|
14
|
Song J, Yang X, Zhang M, Wang C, Chen L. Glutamate Metabolism in Mitochondria is Closely Related to Alzheimer's Disease. J Alzheimers Dis 2021; 84:557-578. [PMID: 34602474 DOI: 10.3233/jad-210595] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Glutamate is the main excitatory neurotransmitter in the brain, and its excitatory neurotoxicity is closely related to the occurrence and development of Alzheimer's disease. However, increasing evidence shows that in the process of Alzheimer's disease, glutamate is not only limited to its excitotoxicity as a neurotransmitter but also related to the disorder of its metabolic balance. The balance of glutamate metabolism in the brain is an important determinant of central nervous system health, and the maintenance of this balance is closely related to glutamate uptake, glutamate circulation, intracellular mitochondrial transport, and mitochondrial metabolism. In this paper, we intend to elaborate the key role of mitochondrial glutamate metabolism in the pathogenesis of Alzheimer's disease and review glutamate metabolism in mitochondria as a potential target in the treatment of Alzheimer's disease.
Collapse
Affiliation(s)
- Jiayi Song
- Department of Pharmacology, Basic College of Medicine, Jilin University, Changchun, People's Republic of China.,Cadre's Ward, The First Hospital of Jilin University, Changchun, People's Republic of China
| | - Xuehan Yang
- Department of Pharmacology, Basic College of Medicine, Jilin University, Changchun, People's Republic of China
| | - Ming Zhang
- Department of Pharmacology, Basic College of Medicine, Jilin University, Changchun, People's Republic of China
| | - Chunyan Wang
- Cadre's Ward, The First Hospital of Jilin University, Changchun, People's Republic of China
| | - Li Chen
- Department of Pharmacology, Basic College of Medicine, Jilin University, Changchun, People's Republic of China
| |
Collapse
|
15
|
Identification of Novel Mutations Contributing to Azole Tolerance of Aspergillus fumigatus through In Vitro Exposure to Tebuconazole. Antimicrob Agents Chemother 2021; 65:e0265720. [PMID: 34125587 DOI: 10.1128/aac.02657-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Azole resistance of Aspergillus fumigatus is a global problem. The major resistance mechanism is through cytochrome P450 14-α sterol demethylase Cyp51A alterations such as a mutation(s) in the gene and the acquisition of a tandem repeat in the promoter. Although other azole tolerance and resistance mechanisms, such as the hmg1 (a 3-hydroxy-3-methylglutaryl coenzyme-A reductase gene) mutation, are known, few reports have described studies elucidating non-Cyp51A resistance mechanisms. This study explored genes contributing to azole tolerance in A. fumigatus by in vitro mutant selection with tebuconazole, an azole fungicide. After three rounds of selection, we obtained four isolates with low susceptibility to tebuconazole. These isolates also showed low susceptibility to itraconazole and voriconazole. Comparison of the genome sequences of the isolates obtained and the parental strain revealed a nonsynonymous mutation in MfsD, a major facilitator superfamily protein (Afu1g11820; R337L mutation [a change of R to L at position 337]), in all isolates. Furthermore, nonsynonymous mutations in AgcA, a mitochondrial inner membrane aspartate/glutamate transporter (Afu7g05220; E535Stop mutation), UbcD, a ubiquitin-conjugating enzyme E2 (Afu3g06030; T98K mutation), AbcJ, an ABC transporter (Afu3g12220; G297E mutation), and RttA, a putative protein responsible for tebuconazole tolerance (Afu7g04740; A83T mutation), were found in at least one isolate. Disruption of the agcA gene led to decreased susceptibility to azoles. Reconstruction of the A83T point mutation in RttA led to decreased susceptibility to azoles. Reversion of the T98K mutation in UbcD to the wild type led to decreased susceptibility to azoles. These results suggest that these mutations contribute to lowered susceptibility to medical azoles and agricultural azole fungicides.
Collapse
|
16
|
Broeks MH, van Karnebeek CDM, Wanders RJA, Jans JJM, Verhoeven‐Duif NM. Inborn disorders of the malate aspartate shuttle. J Inherit Metab Dis 2021; 44:792-808. [PMID: 33990986 PMCID: PMC8362162 DOI: 10.1002/jimd.12402] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 05/08/2021] [Accepted: 05/12/2021] [Indexed: 12/12/2022]
Abstract
Over the last few years, various inborn disorders have been reported in the malate aspartate shuttle (MAS). The MAS consists of four metabolic enzymes and two transporters, one of them having two isoforms that are expressed in different tissues. Together they form a biochemical pathway that shuttles electrons from the cytosol into mitochondria, as the inner mitochondrial membrane is impermeable to the electron carrier NADH. By shuttling NADH across the mitochondrial membrane in the form of a reduced metabolite (malate), the MAS plays an important role in mitochondrial respiration. In addition, the MAS maintains the cytosolic NAD+ /NADH redox balance, by using redox reactions for the transfer of electrons. This explains why the MAS is also important in sustaining cytosolic redox-dependent metabolic pathways, such as glycolysis and serine biosynthesis. The current review provides insights into the clinical and biochemical characteristics of MAS deficiencies. To date, five out of seven potential MAS deficiencies have been reported. Most of them present with a clinical phenotype of infantile epileptic encephalopathy. Although not specific, biochemical characteristics include high lactate, high glycerol 3-phosphate, a disturbed redox balance, TCA abnormalities, high ammonia, and low serine, which may be helpful in reaching a diagnosis in patients with an infantile epileptic encephalopathy. Current implications for treatment include a ketogenic diet, as well as serine and vitamin B6 supplementation.
Collapse
Affiliation(s)
- Melissa H. Broeks
- Department of Genetics, Section Metabolic DiagnosticsUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Clara D. M. van Karnebeek
- Departments of PediatricsAmsterdam University Medical CenterAmsterdamThe Netherlands
- Department of Pediatrics, Amalia Children's Hospital, Radboud Center for Mitochondrial DiseasesRadboud University Medical CenterNijmegenThe Netherlands
- On behalf of “United for Metabolic Diseases”The Netherlands
| | - Ronald J. A. Wanders
- Departments of Pediatrics and Laboratory Medicine, Laboratory Genetic Metabolic DiseasesAmsterdam University Medical Center, University of AmsterdamAmsterdamThe Netherlands
| | - Judith J. M. Jans
- Department of Genetics, Section Metabolic DiagnosticsUniversity Medical Center UtrechtUtrechtThe Netherlands
- On behalf of “United for Metabolic Diseases”The Netherlands
| | - Nanda M. Verhoeven‐Duif
- Department of Genetics, Section Metabolic DiagnosticsUniversity Medical Center UtrechtUtrechtThe Netherlands
- On behalf of “United for Metabolic Diseases”The Netherlands
| |
Collapse
|
17
|
The mitochondrial aspartate/glutamate carrier (AGC or Aralar1) isoforms in D. melanogaster: biochemical characterization, gene structure, and evolutionary analysis. Biochim Biophys Acta Gen Subj 2021; 1865:129854. [PMID: 33497735 DOI: 10.1016/j.bbagen.2021.129854] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 01/18/2021] [Accepted: 01/19/2021] [Indexed: 11/20/2022]
Abstract
BACKGROUND In man two mitochondrial aspartate/glutamate carrier (AGC) isoforms, known as aralar and citrin, are required to accomplish several metabolic pathways. In order to fill the existing gap of knowledge in Drosophila melanogaster, we have studied aralar1 gene, orthologue of human AGC-encoding genes in this organism. METHODS The blastp algorithm and the "reciprocal best hit" approach have been used to identify the human orthologue of AGCs in Drosophilidae and non-Drosophilidae. Aralar1 proteins have been overexpressed in Escherichia coli and functionally reconstituted into liposomes for transport assays. RESULTS The transcriptional organization of aralar1 comprises six isoforms, three constitutively expressed (aralar1-RA, RD and RF), and the remaining three distributed during the development or in different tissues (aralar1-RB, RC and RE). Aralar1-PA and Aralar1-PE, representative of all isoforms, have been biochemically characterized. Recombinant Aralar1-PA and Aralar1-PE proteins share similar efficiency to exchange glutamate against aspartate, and same substrate affinities than the human isoforms. Interestingly, although Aralar1-PA and Aralar1-PE diverge only in their EF-hand 8, they greatly differ in their specific activities and substrate specificity. CONCLUSIONS The tight regulation of aralar1 transcripts expression and the high request of aspartate and glutamate during early embryogenesis suggest a crucial role of Aralar1 in this Drosophila developmental stage. Furthermore, biochemical characterization and calcium sensitivity have identified Aralar1-PA and Aralar1-PE as the human aralar and citrin counterparts, respectively. GENERAL SIGNIFICANCE The functional characterization of the fruit fly mitochondrial AGC transporter represents a crucial step toward a complete understanding of the metabolic events acting during early embryogenesis.
Collapse
|
18
|
βOHB Protective Pathways in Aralar-KO Neurons and Brain: An Alternative to Ketogenic Diet. J Neurosci 2020; 40:9293-9305. [PMID: 33087477 DOI: 10.1523/jneurosci.0711-20.2020] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 08/24/2020] [Accepted: 08/29/2020] [Indexed: 12/19/2022] Open
Abstract
Aralar/AGC1/Slc25a12, the mitochondrial aspartate-glutamate carrier expressed in neurons, is the regulatory component of the NADH malate-aspartate shuttle. AGC1 deficiency is a neuropediatric rare disease characterized by hypomyelination, hypotonia, developmental arrest, and epilepsy. We have investigated whether β-hydroxybutyrate (βOHB), the main ketone body (KB) produced in ketogenic diet (KD), is neuroprotective in aralar-knock-out (KO) neurons and mice. We report that βOHB efficiently recovers aralar-KO neurons from deficits in basal-stimulated and glutamate-stimulated respiration, effects requiring βOHB entry into the neuron, and protects from glutamate excitotoxicity. Aralar-deficient mice were fed a KD to investigate its therapeutic potential early in development, but this approach was unfeasible. Therefore, aralar-KO pups were treated without distinction of gender with daily intraperitoneal injections of βOHB during 5 d. This treatment resulted in a recovery of striatal markers of the dopaminergic system including dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC)/DA ratio, and vesicular monoamine transporter 2 (VMAT2) protein. Regarding postnatal myelination, myelin basic protein (MBP) and myelin-associated glycoprotein (MAG) myelin proteins were markedly increased in the cortices of βOHB-treated aralar-KO mice. Although brain Asp and NAA levels did not change by βOHB administration, a 4-d βOHB treatment to aralar-KO, but not to control, neurons led to a substantial increase in Asp (3-fold) and NAA (4-fold) levels. These results suggest that the lack of increase in brain Asp and NAA is possibly because of its active utilization by the aralar-KO brain and the likely involvement of neuronal NAA in postnatal myelination in these mice. The effectiveness of βOHB as a therapeutic treatment in AGC1 deficiency deserves further investigation.SIGNIFICANCE STATEMENT Aralar deficiency induces a fatal phenotype in humans and mice and is associated with impaired neurodevelopment, epilepsy, and hypomyelination. In neurons, highly expressing aralar, its deficiency causes a metabolic blockade hampering mitochondrial energetics and respiration. Here, we find that βOHB, the main metabolic product in KD, recovers defective mitochondrial respiration bypassing the metabolic failure in aralar-deficient neurons. βOHB oxidation in mitochondria boosts the synthesis of cytosolic aspartate (Asp) and NAA, which is impeded by aralar deficiency, presumably through citrate-malate shuttle. In aralar-knock-out (KO) mice, βOHB recovers from the drastic drop in specific dopaminergic and myelin markers. The βOHB-induced myelin synthesis occurring together with the marked increment in neuronal NAA synthesis supports the role of NAA as a lipid precursor during postnatal myelination.
Collapse
|
19
|
Li B, Zhang T, Liu W, Wang Y, Xu R, Zeng S, Zhang R, Zhu S, Gillies MC, Zhu L, Du J. Metabolic Features of Mouse and Human Retinas: Rods versus Cones, Macula versus Periphery, Retina versus RPE. iScience 2020; 23:101672. [PMID: 33196018 PMCID: PMC7644940 DOI: 10.1016/j.isci.2020.101672] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/21/2020] [Accepted: 10/08/2020] [Indexed: 02/07/2023] Open
Abstract
Photoreceptors, especially cones, which are enriched in the human macula, have high energy demands, making them vulnerable to metabolic stress. Metabolic dysfunction of photoreceptors and their supporting retinal pigment epithelium (RPE) is an important underlying cause of degenerative retinal diseases. However, how cones and the macula support their exorbitant metabolic demand and communicate with RPE is unclear. By profiling metabolite uptake and release and analyzing metabolic genes, we have found cone-rich retinas and human macula share specific metabolic features with upregulated pathways in pyruvate metabolism, mitochondrial TCA cycle, and lipid synthesis. Human neural retina and RPE have distinct but complementary metabolic features. Retinal metabolism centers on NADH production and neurotransmitter biosynthesis. The retina needs aspartate to sustain its aerobic glycolysis and mitochondrial metabolism. RPE metabolism is directed toward NADPH production and biosynthesis of acetyl-rich metabolites, serine, and others. RPE consumes multiple nutrients, including proline, to produce metabolites for the retina.
Collapse
Affiliation(s)
- Bo Li
- Departments of Ophthalmology and Biochemistry, West Virginia University, WVU Eye Institute, One Medical Center Dr, PO Box 9193, Morgantown, WV 26506, USA.,Department of Ophthalmology, Affiliated Hospital of Yangzhou University, Yangzhou University, Yangzhou, Jiangsu Province 225100, China
| | - Ting Zhang
- Save Sight Institute, Sydney Medical School, University of Sydney, Sydney, NSW 2000, Australia
| | - Wei Liu
- Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA.,Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Yekai Wang
- Departments of Ophthalmology and Biochemistry, West Virginia University, WVU Eye Institute, One Medical Center Dr, PO Box 9193, Morgantown, WV 26506, USA
| | - Rong Xu
- Departments of Ophthalmology and Biochemistry, West Virginia University, WVU Eye Institute, One Medical Center Dr, PO Box 9193, Morgantown, WV 26506, USA
| | - Shaoxue Zeng
- Save Sight Institute, Sydney Medical School, University of Sydney, Sydney, NSW 2000, Australia
| | - Rui Zhang
- Save Sight Institute, Sydney Medical School, University of Sydney, Sydney, NSW 2000, Australia
| | - Siyan Zhu
- Departments of Ophthalmology and Biochemistry, West Virginia University, WVU Eye Institute, One Medical Center Dr, PO Box 9193, Morgantown, WV 26506, USA
| | - Mark C Gillies
- Save Sight Institute, Sydney Medical School, University of Sydney, Sydney, NSW 2000, Australia
| | - Ling Zhu
- Save Sight Institute, Sydney Medical School, University of Sydney, Sydney, NSW 2000, Australia
| | - Jianhai Du
- Departments of Ophthalmology and Biochemistry, West Virginia University, WVU Eye Institute, One Medical Center Dr, PO Box 9193, Morgantown, WV 26506, USA
| |
Collapse
|
20
|
Brain Branched-Chain Amino Acids in Maple Syrup Urine Disease: Implications for Neurological Disorders. Int J Mol Sci 2020; 21:ijms21207490. [PMID: 33050626 PMCID: PMC7590055 DOI: 10.3390/ijms21207490] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 10/02/2020] [Accepted: 10/09/2020] [Indexed: 12/16/2022] Open
Abstract
Maple syrup urine disease (MSUD) is an autosomal recessive disorder caused by decreased activity of the branched-chain α-ketoacid dehydrogenase complex (BCKDC), which catalyzes the irreversible catabolism of branched-chain amino acids (BCAAs). Current management of this BCAA dyshomeostasis consists of dietary restriction of BCAAs and liver transplantation, which aims to partially restore functional BCKDC activity in the periphery. These treatments improve the circulating levels of BCAAs and significantly increase survival rates in MSUD patients. However, significant cognitive and psychiatric morbidities remain. Specifically, patients are at a higher lifetime risk for cognitive impairments, mood and anxiety disorders (depression, anxiety, and panic disorder), and attention deficit disorder. Recent literature suggests that the neurological sequelae may be due to the brain-specific roles of BCAAs. This review will focus on the derangements of BCAAs observed in the brain of MSUD patients and will explore the potential mechanisms driving neurologic dysfunction. Finally, we will discuss recent evidence that implicates the relevance of BCAA metabolism in other neurological disorders. An understanding of the role of BCAAs in the central nervous system may facilitate future identification of novel therapeutic approaches in MSUD and a broad range of neurological disorders.
Collapse
|
21
|
Hillen AEJ, Heine VM. Glutamate Carrier Involvement in Mitochondrial Dysfunctioning in the Brain White Matter. Front Mol Biosci 2020; 7:151. [PMID: 32793632 PMCID: PMC7385250 DOI: 10.3389/fmolb.2020.00151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 06/18/2020] [Indexed: 11/24/2022] Open
Abstract
Glutamate homeostasis is an important determinant of health of the central nervous system (CNS). Mitochondria play crucial roles in glutamate metabolism, especially in processes with a high energy demand such as action potential generation. Mitochondrial glutamate carriers (GCs) and aspartate-GCs (AGCs) regulate the transport of glutamate from the cytoplasm across the mitochondrial membrane, which is needed to control energy demand, lipid metabolism, and metabolic activity including oxidative phosphorylation and glycolysis. Dysfunction in these carriers are associated with seizures, spasticity, and/or myelin deficits, all of which are associated with inherited metabolic disorders. Since solute carrier functioning and associated processes are cell type- and context-specific, selective vulnerability to glutamate excitotoxicity and mitochondrial dysfunctioning is expected. Understanding this could offer important insights into the pathomechanisms of associated disorders. This perspective aims to explore the link between functions of both AGCs and GCs and their role in metabolic disorders, with a focus on a subclass of lysosomal storage disorders called leukodystrophies (LDs).
Collapse
Affiliation(s)
- Anne E J Hillen
- Pediatric Neurology, Emma Children's Hospital, Amsterdam UMC, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Vivi M Heine
- Child and Youth Psychiatry, Emma Children's Hospital, Amsterdam UMC, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam, Netherlands.,Department of Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| |
Collapse
|
22
|
Zyśk M, Sakowicz-Burkiewicz M, Pikul P, Kowalski R, Michno A, Pawełczyk T. The Impact of Acetyl-CoA and Aspartate Shortages on the N-Acetylaspartate Level in Different Models of Cholinergic Neurons. Antioxidants (Basel) 2020; 9:antiox9060522. [PMID: 32545833 PMCID: PMC7346116 DOI: 10.3390/antiox9060522] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 06/03/2020] [Accepted: 06/11/2020] [Indexed: 12/31/2022] Open
Abstract
N-acetylaspartate is produced by neuronal aspartate N-acetyltransferase (NAT8L) from acetyl-CoA and aspartate. In cholinergic neurons, acetyl-CoA is also utilized in the mitochondrial tricarboxylic acid cycle and in acetylcholine production pathways. While aspartate has to be shared with the malate–aspartate shuttle, another mitochondrial machinery together with the tricarboxylic acid cycle supports the electron transport chain turnover. The main goal of this study was to establish the impact of toxic conditions on N-acetylaspartate production. SN56 cholinergic cells were exposed to either Zn2+ overload or Ca2+ homeostasis dysregulation and male adult Wistar rats’ brains were studied after 2 weeks of challenge with streptozotocin-induced hyperglycemia or daily theophylline treatment. Our results allow us to hypothesize that the cholinergic neurons from brain septum prioritized the acetylcholine over N-acetylaspartate production. This report provides the first direct evidence for Zn2+-dependent suppression of N-acetylaspartate synthesis leading to mitochondrial acetyl-CoA and aspartate shortages. Furthermore, Zn2+ is a direct concentration-dependent inhibitor of NAT8L activity, while Zn2+-triggered oxidative stress is unlikely to be significant in such suppression.
Collapse
Affiliation(s)
- Marlena Zyśk
- Department of Molecular Medicine, Medical University of Gdansk, 80-211 Gdansk, Poland; (M.S.-B.); (T.P.)
- Correspondence: ; Tel.: +48-5834-927-70
| | - Monika Sakowicz-Burkiewicz
- Department of Molecular Medicine, Medical University of Gdansk, 80-211 Gdansk, Poland; (M.S.-B.); (T.P.)
| | - Piotr Pikul
- Laboratory of Molecular and Cellular Nephrology, Mossakowski Medical Research Center, Polish Academy of Science, 80-308 Gdansk, Poland;
- Clinical Laboratory University Clinical Center in Gdansk, 80-211 Gdansk, Poland;
| | - Robert Kowalski
- Clinical Laboratory University Clinical Center in Gdansk, 80-211 Gdansk, Poland;
| | - Anna Michno
- Department of Laboratory Medicine, Medical University of Gdansk, 80-2011 Gdansk, Poland;
| | - Tadeusz Pawełczyk
- Department of Molecular Medicine, Medical University of Gdansk, 80-211 Gdansk, Poland; (M.S.-B.); (T.P.)
| |
Collapse
|
23
|
Palmieri F, Scarcia P, Monné M. Diseases Caused by Mutations in Mitochondrial Carrier Genes SLC25: A Review. Biomolecules 2020; 10:biom10040655. [PMID: 32340404 PMCID: PMC7226361 DOI: 10.3390/biom10040655] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/15/2020] [Accepted: 04/17/2020] [Indexed: 12/13/2022] Open
Abstract
In the 1980s, after the mitochondrial DNA (mtDNA) had been sequenced, several diseases resulting from mtDNA mutations emerged. Later, numerous disorders caused by mutations in the nuclear genes encoding mitochondrial proteins were found. A group of these diseases are due to defects of mitochondrial carriers, a family of proteins named solute carrier family 25 (SLC25), that transport a variety of solutes such as the reagents of ATP synthase (ATP, ADP, and phosphate), tricarboxylic acid cycle intermediates, cofactors, amino acids, and carnitine esters of fatty acids. The disease-causing mutations disclosed in mitochondrial carriers range from point mutations, which are often localized in the substrate translocation pore of the carrier, to large deletions and insertions. The biochemical consequences of deficient transport are the compartmentalized accumulation of the substrates and dysfunctional mitochondrial and cellular metabolism, which frequently develop into various forms of myopathy, encephalopathy, or neuropathy. Examples of diseases, due to mitochondrial carrier mutations are: combined D-2- and L-2-hydroxyglutaric aciduria, carnitine-acylcarnitine carrier deficiency, hyperornithinemia-hyperammonemia-homocitrillinuria (HHH) syndrome, early infantile epileptic encephalopathy type 3, Amish microcephaly, aspartate/glutamate isoform 1 deficiency, congenital sideroblastic anemia, Fontaine progeroid syndrome, and citrullinemia type II. Here, we review all the mitochondrial carrier-related diseases known until now, focusing on the connections between the molecular basis, altered metabolism, and phenotypes of these inherited disorders.
Collapse
Affiliation(s)
- Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, via E. Orabona 4, 70125 Bari, Italy;
- Correspondence: (F.P.); (M.M.); Tel.: +39-0805443323 (F.P.)
| | - Pasquale Scarcia
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, via E. Orabona 4, 70125 Bari, Italy;
| | - Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, via E. Orabona 4, 70125 Bari, Italy;
- Department of Sciences, University of Basilicata, via Ateneo Lucano 10, 85100 Potenza, Italy
- Correspondence: (F.P.); (M.M.); Tel.: +39-0805443323 (F.P.)
| |
Collapse
|
24
|
Varfolomeev SD, Bykov VI, Semenova NA, Tsybenova SB. Kinetic Modeling of the Blood Oxygenation Level Dependent (BOLD) Signals and Biocatalytic Reactions Observed in the Human Brain Using MRI: An Analysis of Normal and Pathological Conditions. ACS Chem Neurosci 2020; 11:763-771. [PMID: 32039588 DOI: 10.1021/acschemneuro.9b00671] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A kinetic model describing the pulse of increased oxygen concentrations and the subsequent changes in the concentration of N-acetylaspartate in the excited nervous tissue of the human brain in response to an external signal is presented. The model is based on biochemical data, a multistage and nonlinear dynamic process the BOLD signal and N-acetylaspartate. The existence of multiple steady states explains the triggering effect of the system. The inhibitory effect of the substrate is a necessary factor for the autostabilization of N-acetylaspartate. The kinetic model allows the dynamic behavior of previously unmeasurable metabolites, namely, products of the hydrolysis of N-acetylaspartate, such as acetic and aspartic acid, and glutamic acid to be predicted. Kinetic modeling of the BOLD signal and the subsequent hydrolysis of N-acetylaspartate provides information about the biochemical and dynamic characteristics of some pathological conditions (schizophrenia, Canavan disease, and the superexcitation of the neural network).
Collapse
Affiliation(s)
- Sergey D. Varfolomeev
- Lomonosov Moscow State University, Institute of Physical and Chemical Grounds of Neuronet Functions and Artificial Intelligence, Moscow 119991, Russia
- Emanuel Institute of Biochemical Physics, Moscow 119334, Russia
| | | | | | | |
Collapse
|
25
|
Blajszczak CC, Nonn L. Vitamin D regulates prostate cell metabolism via genomic and non-genomic mitochondrial redox-dependent mechanisms. J Steroid Biochem Mol Biol 2019; 195:105484. [PMID: 31574299 PMCID: PMC7040883 DOI: 10.1016/j.jsbmb.2019.105484] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 09/10/2019] [Accepted: 09/21/2019] [Indexed: 01/05/2023]
Abstract
Vitamin D deficiency has been associated with increased risk for aggressive prostate cancer (PCa). Prostate epithelium has a unique metabolism compared to other tissues. Normal prostate exhibits low levels of mitochondrial respiration and there is a metabolic switch to increased oxidative phosphorylation in PCa. 25-hydroxyvitamin D (25(OH)D) is the major circulating form of vitamin D and is used clinically to determine vitamin D status. Activation of 25(OH)D to the transcriptionally active form, 1,25(OH)2D occurs via a reduction-oxidation (redox) reaction within the mitochondria that is catalyzed by the P450 enzyme, CYP27B1. We sought to determine if hydroxylation of 25(OH)D by CYP27B1 contributes to non-genomic activity of vitamin D by altering the redox-dependent state of the mitochondria in benign prostate epithelial cells. Exposure to 25(OH)D produced a transient pro-oxidant effect and change in mitochondrial membrane potential that was dependent on CYP27B1. Extended exposure ultimately suppressed mitochondrial respiration, consistent with a protective effect of 25(OH)D in supporting benign prostate metabolism. To model physiologically relevant changes in vitamin D, cells were cultured in constant 25(OH)D then changed to high or deficient concentrations. This model also incurred a biphasic effect with a pro-oxidant shift after short exposure followed by decreased respiration after 16 h. Several genes involved in redox cycling and Mitochondrial Health were regulated by 25(OH)D in these cells. These results indicate a secondary non-genomic mechanism for vitamin D to contribute to prostate cell health by supporting normal mitochondrial respiration.
Collapse
Affiliation(s)
- Chuck C Blajszczak
- Department of Pathology, University of Illinois at Chicago, 840 S Wood St., Chicago, IL 60612, USA
| | - Larisa Nonn
- Department of Pathology, University of Illinois at Chicago, 840 S Wood St., Chicago, IL 60612, USA; University of Illinois Cancer Center, Chicago, IL 60612, USA.
| |
Collapse
|
26
|
Wang Y, Hussein AM, Somasundaram L, Sankar R, Detraux D, Mathieu J, Ruohola-Baker H. microRNAs Regulating Human and Mouse Naïve Pluripotency. Int J Mol Sci 2019; 20:E5864. [PMID: 31766734 PMCID: PMC6929104 DOI: 10.3390/ijms20235864] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 11/07/2019] [Accepted: 11/13/2019] [Indexed: 12/16/2022] Open
Abstract
microRNAs are ~22bp nucleotide non-coding RNAs that play important roles in the post-transcriptional regulation of gene expression. Many studies have established that microRNAs are important for cell fate choices, including the naïve to primed pluripotency state transitions, and their intermediate state, the developmentally suspended diapause state in early development. However, the full extent of microRNAs associated with these stage transitions in human and mouse remain under-explored. By meta-analysis of microRNA-seq, RNA-seq, and metabolomics datasets from human and mouse, we found a set of microRNAs, and importantly, their experimentally validated target genes that show consistent changes in naïve to primed transitions (microRNA up, target genes down, or vice versa). The targets of these microRNAs regulate developmental pathways (e.g., the Hedgehog-pathway), primary cilium, and remodeling of metabolic processes (oxidative phosphorylation, fatty acid metabolism, and amino acid transport) during the transition. Importantly, we identified 115 microRNAs that significantly change in the same direction in naïve to primed transitions in both human and mouse, many of which are novel candidate regulators of pluripotency. Furthermore, we identified 38 microRNAs and 274 target genes that may be involved in diapause, where embryonic development is temporarily suspended prior to implantation to uterus. The upregulated target genes suggest that microRNAs activate stress response in the diapause stage. In conclusion, we provide a comprehensive resource of microRNAs and their target genes involved in naïve to primed transition and in the paused intermediate, the embryonic diapause stage.
Collapse
Affiliation(s)
- Yuliang Wang
- Paul G. Allen School of Computer Science & Engineering, University of Washington, Seattle, WA 98195, USA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA; (A.M.H.); (L.S.); (R.S.); (D.D.)
| | - Abdiasis M. Hussein
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA; (A.M.H.); (L.S.); (R.S.); (D.D.)
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Logeshwaran Somasundaram
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA; (A.M.H.); (L.S.); (R.S.); (D.D.)
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Rithika Sankar
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA; (A.M.H.); (L.S.); (R.S.); (D.D.)
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Damien Detraux
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA; (A.M.H.); (L.S.); (R.S.); (D.D.)
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
- Department of Comparative Medicine, University of Washington, Seattle, WA 98195, USA
| | - Julie Mathieu
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA; (A.M.H.); (L.S.); (R.S.); (D.D.)
- Department of Comparative Medicine, University of Washington, Seattle, WA 98195, USA
| | - Hannele Ruohola-Baker
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA; (A.M.H.); (L.S.); (R.S.); (D.D.)
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| |
Collapse
|
27
|
Petralla S, Peña-Altamira LE, Poeta E, Massenzio F, Virgili M, Barile SN, Sbano L, Profilo E, Corricelli M, Danese A, Giorgi C, Ostan R, Capri M, Pinton P, Palmieri F, Lasorsa FM, Monti B. Deficiency of Mitochondrial Aspartate-Glutamate Carrier 1 Leads to Oligodendrocyte Precursor Cell Proliferation Defects Both In Vitro and In Vivo. Int J Mol Sci 2019; 20:ijms20184486. [PMID: 31514314 PMCID: PMC6769484 DOI: 10.3390/ijms20184486] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 09/04/2019] [Accepted: 09/06/2019] [Indexed: 11/16/2022] Open
Abstract
Aspartate-Glutamate Carrier 1 (AGC1) deficiency is a rare neurological disease caused by mutations in the solute carrier family 25, member 12 (SLC25A12) gene, encoding for the mitochondrial aspartate-glutamate carrier isoform 1 (AGC1), a component of the malate-aspartate NADH shuttle (MAS), expressed in excitable tissues only. AGC1 deficiency patients are children showing severe hypotonia, arrested psychomotor development, seizures and global hypomyelination. While the effect of AGC1 deficiency in neurons and neuronal function has been deeply studied, little is known about oligodendrocytes and their precursors, the brain cells involved in myelination. Here we studied the effect of AGC1 down-regulation on oligodendrocyte precursor cells (OPCs), using both in vitro and in vivo mouse disease models. In the cell model, we showed that a reduced expression of AGC1 induces a deficit of OPC proliferation leading to their spontaneous and precocious differentiation into oligodendrocytes. Interestingly, this effect seems to be related to a dysregulation in the expression of trophic factors and receptors involved in OPC proliferation/differentiation, such as Platelet-Derived Growth Factor α (PDGFα) and Transforming Growth Factor βs (TGFβs). We also confirmed the OPC reduction in vivo in AGC1-deficent mice, as well as a proliferation deficit in neurospheres from the Subventricular Zone (SVZ) of these animals, thus indicating that AGC1 reduction could affect the proliferation of different brain precursor cells. These data clearly show that AGC1 impairment alters myelination not only by acting on N-acetyl-aspartate production in neurons but also on OPC proliferation and suggest new potential therapeutic targets for the treatment of AGC1 deficiency.
Collapse
Affiliation(s)
- Sabrina Petralla
- Department of Pharmacy and BioTechnology, University of Bologna, 40126 Bologna, Italy; (S.P.); (L.E.P.-A.); (E.P.); (F.M.); (M.V.)
| | - Luis Emiliano Peña-Altamira
- Department of Pharmacy and BioTechnology, University of Bologna, 40126 Bologna, Italy; (S.P.); (L.E.P.-A.); (E.P.); (F.M.); (M.V.)
| | - Eleonora Poeta
- Department of Pharmacy and BioTechnology, University of Bologna, 40126 Bologna, Italy; (S.P.); (L.E.P.-A.); (E.P.); (F.M.); (M.V.)
| | - Francesca Massenzio
- Department of Pharmacy and BioTechnology, University of Bologna, 40126 Bologna, Italy; (S.P.); (L.E.P.-A.); (E.P.); (F.M.); (M.V.)
| | - Marco Virgili
- Department of Pharmacy and BioTechnology, University of Bologna, 40126 Bologna, Italy; (S.P.); (L.E.P.-A.); (E.P.); (F.M.); (M.V.)
| | - Simona Nicole Barile
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70121 Bari, Italy (E.P.); (F.P.)
| | - Luigi Sbano
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, 44121 Ferrara, Italy; (L.S.); (M.C.); (A.D.); (C.G.); (P.P.)
| | - Emanuela Profilo
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70121 Bari, Italy (E.P.); (F.P.)
| | - Mariangela Corricelli
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, 44121 Ferrara, Italy; (L.S.); (M.C.); (A.D.); (C.G.); (P.P.)
| | - Alberto Danese
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, 44121 Ferrara, Italy; (L.S.); (M.C.); (A.D.); (C.G.); (P.P.)
| | - Carlotta Giorgi
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, 44121 Ferrara, Italy; (L.S.); (M.C.); (A.D.); (C.G.); (P.P.)
| | - Rita Ostan
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES, Dipartimento di Medicina Specialistica Diagnostica e Sperimentale) and C.I.G. Interdepartmental Centre “L. Galvani”, University of Bologna, 40126 Bologna, Italy; (R.O.); (M.C.)
| | - Miriam Capri
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES, Dipartimento di Medicina Specialistica Diagnostica e Sperimentale) and C.I.G. Interdepartmental Centre “L. Galvani”, University of Bologna, 40126 Bologna, Italy; (R.O.); (M.C.)
| | - Paolo Pinton
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology and Experimental Biology, Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, 44121 Ferrara, Italy; (L.S.); (M.C.); (A.D.); (C.G.); (P.P.)
- Maria Cecilia Hospital, GVM Care & Research, Cotignola, 48010 Ravenna, Italy
| | - Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70121 Bari, Italy (E.P.); (F.P.)
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies IBIOM, CNR, 70126 Bari, Italy
| | - Francesco Massimo Lasorsa
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies IBIOM, CNR, 70126 Bari, Italy
- Correspondence: (F.M.L.); (B.M.); Tel.: +39-080-544-2772 (F.M.L.); +39-051-209-4134 (B.M.)
| | - Barbara Monti
- Department of Pharmacy and BioTechnology, University of Bologna, 40126 Bologna, Italy; (S.P.); (L.E.P.-A.); (E.P.); (F.M.); (M.V.)
- Correspondence: (F.M.L.); (B.M.); Tel.: +39-080-544-2772 (F.M.L.); +39-051-209-4134 (B.M.)
| |
Collapse
|
28
|
Mitochondrial Carriers for Aspartate, Glutamate and Other Amino Acids: A Review. Int J Mol Sci 2019; 20:ijms20184456. [PMID: 31510000 PMCID: PMC6769469 DOI: 10.3390/ijms20184456] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 09/05/2019] [Accepted: 09/06/2019] [Indexed: 12/19/2022] Open
Abstract
Members of the mitochondrial carrier (MC) protein family transport various molecules across the mitochondrial inner membrane to interlink steps of metabolic pathways and biochemical processes that take place in different compartments; i.e., are localized partly inside and outside the mitochondrial matrix. MC substrates consist of metabolites, inorganic anions (such as phosphate and sulfate), nucleotides, cofactors and amino acids. These compounds have been identified by in vitro transport assays based on the uptake of radioactively labeled substrates into liposomes reconstituted with recombinant purified MCs. By using this approach, 18 human, plant and yeast MCs for amino acids have been characterized and shown to transport aspartate, glutamate, ornithine, arginine, lysine, histidine, citrulline and glycine with varying substrate specificities, kinetics, influences of the pH gradient, and capacities for the antiport and uniport mode of transport. Aside from providing amino acids for mitochondrial translation, the transport reactions catalyzed by these MCs are crucial in energy, nitrogen, nucleotide and amino acid metabolism. In this review we dissect the transport properties, phylogeny, regulation and expression levels in different tissues of MCs for amino acids, and summarize the main structural aspects known until now about MCs. The effects of their disease-causing mutations and manipulation of their expression levels in cells are also considered as clues for understanding their physiological functions.
Collapse
|
29
|
Puertas-Frías G, Del Arco A, Pardo B, Satrústegui J, Contreras L. Mitochondrial movement in Aralar/Slc25a12/AGC1 deficient cortical neurons. Neurochem Int 2019; 131:104541. [PMID: 31472174 DOI: 10.1016/j.neuint.2019.104541] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 07/25/2019] [Accepted: 08/28/2019] [Indexed: 12/12/2022]
Abstract
The elevated energy demands in the brain are fulfilled mainly by glucose catabolism. In highly polarized neurons, about 10-50% of mitochondria are transported along microtubules using mitochondrial-born ATP to locations with high energy requirements. In this report, we have investigated the impact of Aralar deficiency on mitochondrial transport in cultured cortical neurons. Aralar/slc25a12/AGC1 is the neuronal isoform of the aspartate-glutamate mitochondrial carrier, a component of the malate-aspartate shuttle (MAS) which plays an important role in redox balance, which is essential to maintain glycolytic pyruvate supply to neuronal mitochondria. Using live imaging microscopy we observed that the lack of Aralar does not affect the number of moving mitochondria nor the Ca2+-induced stop, the only difference being a 10% increase in mitochondrial velocity in Aralar deficient neurons. Therefore, we evaluated the possible fuels used in each case by studying the relative contribution of oxidative phosphorylation and glycolysis to mitochondrial movement using specific inhibitors. We found that the ATP synthase inhibitor oligomycin caused a smaller inhibition of mitochondrial movement in Aralar-KO than control neurons, whereas the glycolysis inhibitor iodoacetate had similar effects in neurons from both genotypes. In line with these findings, the decrease in cytosolic ATP/ADP ratio caused by oligomycin was more pronounced in control than in Aralar-KO neurons, but no differences were observed with iodoacetate. Oligomycin effect was reverted by aralar re-expression in knock out cultures. As mitochondrial movement is not reduced in Aralar-KO neurons, these results suggest that these neurons may use an additional pathway for mitochondria movement and ATP/ADP ratio maintenance.
Collapse
Affiliation(s)
- Guillermo Puertas-Frías
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049, Madrid, Spain
| | - Araceli Del Arco
- Facultad de Ciencias Ambientales y Bioquímica, Centro Regional de Investigaciones Biomédicas, Universidad de Castilla La Mancha, 45071, Toledo, Spain; Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IISFJD), 28049, Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28049, Madrid, Spain
| | - Beatriz Pardo
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049, Madrid, Spain; Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IISFJD), 28049, Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28049, Madrid, Spain
| | - Jorgina Satrústegui
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049, Madrid, Spain; Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IISFJD), 28049, Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28049, Madrid, Spain
| | - Laura Contreras
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049, Madrid, Spain; Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IISFJD), 28049, Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28049, Madrid, Spain.
| |
Collapse
|
30
|
Kavanaugh BC, Warren EB, Baytas O, Schmidt M, Merck D, Buch K, Liu JS, Phornphutkul C, Caruso P, Morrow EM. Longitudinal MRI findings in patient with SLC25A12 pathogenic variants inform disease progression and classification. Am J Med Genet A 2019; 179:2284-2291. [PMID: 31403263 PMCID: PMC6788951 DOI: 10.1002/ajmg.a.61322] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 07/24/2019] [Accepted: 07/25/2019] [Indexed: 11/10/2022]
Abstract
Aspartate-glutamate carrier 1 (AGC1) is one of two exchangers within the malate-aspartate shuttle. AGC1 is encoded by the SLC25A12 gene. Three patients with pathogenic variants in SLC25A12 have been reported in the literature. These patients were clinically characterized by neurodevelopmental delay, epilepsy, hypotonia, cerebral atrophy, and hypomyelination; however, there has been discussion in the literature as to whether this hypomyelination is primary or secondary to a neuronal defect. Here we report a 12-year-old patient with variants in SLC25A12 and magnetic resonance imaging (MRI) at multiple ages. Novel compound heterozygous, recessive variants in SLC25A12 were identified: c.1295C>T (p.A432V) and c.1447-2_1447-1delAG. Clinical presentation is characterized by severe intellectual disability, nonambulatory, nonverbal status, hypotonia, epilepsy, spastic quadriplegia, and a happy disposition. The serial neuroimaging findings are notable for cerebral atrophy with white matter involvement, namely, early hypomyelination yet subsequent progression of myelination. The longitudinal MRI findings are most consistent with a leukodystrophy of the leuko-axonopathy category, that is, white matter abnormalities that are most suggestive of mechanisms that result from primary neuronal defects. We present here the first case of a patient with compound heterozygous variants in SLC25A12, including brain MRI findings, in the oldest individual reported to date with this neurogenetic condition.
Collapse
Affiliation(s)
- Brian C Kavanaugh
- Developmental Disorders Genetics Research Program, Department of Psychiatry and Human Behavior, Warren Alpert Medical School of Brown University and Emma Pendleton Bradley Hospital, East Providence, Rhode Island.,Hassenfeld Child Health Innovation Institute, Brown University, Providence, Rhode Island
| | - Emily B Warren
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island
| | - Ozan Baytas
- Developmental Disorders Genetics Research Program, Department of Psychiatry and Human Behavior, Warren Alpert Medical School of Brown University and Emma Pendleton Bradley Hospital, East Providence, Rhode Island.,Hassenfeld Child Health Innovation Institute, Brown University, Providence, Rhode Island.,Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island
| | - Michael Schmidt
- Developmental Disorders Genetics Research Program, Department of Psychiatry and Human Behavior, Warren Alpert Medical School of Brown University and Emma Pendleton Bradley Hospital, East Providence, Rhode Island.,Hassenfeld Child Health Innovation Institute, Brown University, Providence, Rhode Island.,Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island
| | - Derek Merck
- Department of Diagnostic Imaging, Rhode Island Hospital and Warren Alpert Medical School of Brown University, Providence, Rhode Island
| | - Karen Buch
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Judy S Liu
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island.,Department of Neurology, Rhode Island Hospital and Warren Alpert Medical School of Brown University, Providence, Rhode Island.,Center for Translational Neuroscience, Robert J. and Nancy D. Carney Institute for Brain Science and Brown Institute for Translational Science, Brown University, Providence, Rhode Island
| | - Chanika Phornphutkul
- Department of Pediatrics, Division of Human Genetics, Rhode Island Hospital and Warren Alpert Medical School of Brown University, Providence, Rhode Island
| | - Paul Caruso
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Eric M Morrow
- Developmental Disorders Genetics Research Program, Department of Psychiatry and Human Behavior, Warren Alpert Medical School of Brown University and Emma Pendleton Bradley Hospital, East Providence, Rhode Island.,Hassenfeld Child Health Innovation Institute, Brown University, Providence, Rhode Island.,Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island.,Center for Translational Neuroscience, Robert J. and Nancy D. Carney Institute for Brain Science and Brown Institute for Translational Science, Brown University, Providence, Rhode Island
| |
Collapse
|
31
|
fMRI and MR-spectroscopy in research on triggering and autostabilization of N-acetylaspartate. Chem Phys Lett 2019. [DOI: 10.1016/j.cplett.2019.05.033] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
32
|
Gospe SM, Travis AM, Kolesnikov AV, Klingeborn M, Wang L, Kefalov VJ, Arshavsky VY. Photoreceptors in a mouse model of Leigh syndrome are capable of normal light-evoked signaling. J Biol Chem 2019; 294:12432-12443. [PMID: 31248988 DOI: 10.1074/jbc.ra119.007945] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 06/12/2019] [Indexed: 11/06/2022] Open
Abstract
Mitochondrial dysfunction is an important cause of heritable vision loss. Mutations affecting mitochondrial bioenergetics may lead to isolated vision loss or life-threatening systemic disease, depending on a mutation's severity. Primary optic nerve atrophy resulting from death of retinal ganglion cells is the most prominent ocular manifestation of mitochondrial disease. However, dysfunction of other retinal cell types has also been described, sometimes leading to a loss of photoreceptors and retinal pigment epithelium that manifests clinically as pigmentary retinopathy. A popular mouse model of mitochondrial disease that lacks NADH:ubiquinone oxidoreductase subunit S4 (NDUFS4), a subunit of mitochondrial complex I, phenocopies many traits of the human disease Leigh syndrome, including the development of optic atrophy. It has also been reported that ndufs4 -/- mice display diminished light responses at the level of photoreceptors or bipolar cells. By conducting electroretinography (ERG) recordings in live ndufs4 -/- mice, we now demonstrate that this defect occurs at the level of retinal photoreceptors. We found that this deficit does not arise from retinal developmental anomalies, photoreceptor degeneration, or impaired regeneration of visual pigment. Strikingly, the impairment of ndufs4 -/- photoreceptor function was not observed in ex vivo ERG recordings from isolated retinas, indicating that photoreceptors with complex I deficiency are intrinsically capable of normal signaling. The difference in electrophysiological phenotypes in vivo and ex vivo suggests that the energy deprivation associated with severe mitochondrial impairment in the outer retina renders ndufs4 -/- photoreceptors unable to maintain the homeostatic conditions required to operate at their normal capacity.
Collapse
Affiliation(s)
- Sidney M Gospe
- Department of Ophthalmology, Duke University, Durham, North Carolina 27710.
| | - Amanda M Travis
- Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina 27710
| | - Alexander V Kolesnikov
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, Missouri 63110
| | - Mikael Klingeborn
- Department of Ophthalmology, Duke University, Durham, North Carolina 27710
| | - Luyu Wang
- Department of Ophthalmology, Duke University, Durham, North Carolina 27710
| | - Vladimir J Kefalov
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, Missouri 63110
| | - Vadim Y Arshavsky
- Department of Ophthalmology, Duke University, Durham, North Carolina 27710; Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina 27710
| |
Collapse
|
33
|
Agudelo LZ, Ferreira DMS, Dadvar S, Cervenka I, Ketscher L, Izadi M, Zhengye L, Furrer R, Handschin C, Venckunas T, Brazaitis M, Kamandulis S, Lanner JT, Ruas JL. Skeletal muscle PGC-1α1 reroutes kynurenine metabolism to increase energy efficiency and fatigue-resistance. Nat Commun 2019; 10:2767. [PMID: 31235694 PMCID: PMC6591322 DOI: 10.1038/s41467-019-10712-0] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 05/22/2019] [Indexed: 12/02/2022] Open
Abstract
The coactivator PGC-1α1 is activated by exercise training in skeletal muscle and promotes fatigue-resistance. In exercised muscle, PGC-1α1 enhances the expression of kynurenine aminotransferases (Kats), which convert kynurenine into kynurenic acid. This reduces kynurenine-associated neurotoxicity and generates glutamate as a byproduct. Here, we show that PGC-1α1 elevates aspartate and glutamate levels and increases the expression of glycolysis and malate-aspartate shuttle (MAS) genes. These interconnected processes improve energy utilization and transfer fuel-derived electrons to mitochondrial respiration. This PGC-1α1-dependent mechanism allows trained muscle to use kynurenine metabolism to increase the bioenergetic efficiency of glucose oxidation. Kat inhibition with carbidopa impairs aspartate biosynthesis, mitochondrial respiration, and reduces exercise performance and muscle force in mice. Our findings show that PGC-1α1 activates the MAS in skeletal muscle, supported by kynurenine catabolism, as part of the adaptations to endurance exercise. This crosstalk between kynurenine metabolism and the MAS may have important physiological and clinical implications. PGC-1α is activated by exercise and promotes resistance to fatigue in muscles. Here, the authors show that PGC-1α activates the malate-aspartate shuttle, and allows muscle to utilise kynurenine, leading to more efficient glucose oxidation and mitochondrial respiration.
Collapse
Affiliation(s)
- Leandro Z Agudelo
- Department of Physiology and Pharmacology, Molecular and Cellular Exercise Physiology, Karolinska Institutet, Biomedicum C5, 171 77, Stockholm, Sweden.,Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Duarte M S Ferreira
- Department of Physiology and Pharmacology, Molecular and Cellular Exercise Physiology, Karolinska Institutet, Biomedicum C5, 171 77, Stockholm, Sweden
| | - Shamim Dadvar
- Department of Physiology and Pharmacology, Molecular and Cellular Exercise Physiology, Karolinska Institutet, Biomedicum C5, 171 77, Stockholm, Sweden
| | - Igor Cervenka
- Department of Physiology and Pharmacology, Molecular and Cellular Exercise Physiology, Karolinska Institutet, Biomedicum C5, 171 77, Stockholm, Sweden
| | - Lars Ketscher
- Department of Physiology and Pharmacology, Molecular and Cellular Exercise Physiology, Karolinska Institutet, Biomedicum C5, 171 77, Stockholm, Sweden
| | - Manizheh Izadi
- Department of Physiology and Pharmacology, Molecular and Cellular Exercise Physiology, Karolinska Institutet, Biomedicum C5, 171 77, Stockholm, Sweden
| | - Liu Zhengye
- Department of Physiology and Pharmacology, Molecular Muscle Physiology and Pathophysiology, Karolinska Institutet, Biomedicum C5, 171 77, Stockholm, Sweden
| | - Regula Furrer
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, CH-4056, Basel, Switzerland
| | - Christoph Handschin
- Biozentrum, University of Basel, Klingelbergstrasse 50/70, CH-4056, Basel, Switzerland
| | - Tomas Venckunas
- Institute of Sports Science and Innovations, Lithuanian Sports University, Sporto str. 6, 44221, Kaunas, Lithuania
| | - Marius Brazaitis
- Institute of Sports Science and Innovations, Lithuanian Sports University, Sporto str. 6, 44221, Kaunas, Lithuania
| | - Sigitas Kamandulis
- Institute of Sports Science and Innovations, Lithuanian Sports University, Sporto str. 6, 44221, Kaunas, Lithuania
| | - Johanna T Lanner
- Department of Physiology and Pharmacology, Molecular Muscle Physiology and Pathophysiology, Karolinska Institutet, Biomedicum C5, 171 77, Stockholm, Sweden
| | - Jorge L Ruas
- Department of Physiology and Pharmacology, Molecular and Cellular Exercise Physiology, Karolinska Institutet, Biomedicum C5, 171 77, Stockholm, Sweden.
| |
Collapse
|
34
|
Downregulation of aspartoacylase during the progression of myelin breakdown in the dmy mutant rat with mitochondrial magnesium channel MRS2 defect. Brain Res 2019; 1718:169-175. [PMID: 31100216 DOI: 10.1016/j.brainres.2019.05.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 05/11/2019] [Accepted: 05/13/2019] [Indexed: 11/22/2022]
Abstract
OBJECTIVE The dmy rat is an autosomal recessive mutant that exhibits severe rapid myelin breakdown throughout the central nervous system at 7-8 weeks of age. The dmy rat has a point mutation in Mrs2 gene, which encodes an essential component of the major electrophoretic Mg2+ influx system in the mitochondria. However, it remains unknown how mitochondrial dysfunction leads to the myelin breakdown. METHODS We focused on the aspartoacylase (ASPA) and mitochondrion-related metabolites to clarify the mechanism of myelin pathology in dmy rats. Aspa mRNA was significantly decreased in both the gray matter and the ventral white matter of spinal cord in the dmy rats from 4 to 8 weeks of age. Very faint immunohistochemical expression for ASPA was noted in the gray and white matter of the affected dmy rats at 8 weeks. Liquid chromatography mass spectrometry revealed no different amount of N-acetylaspartate (NAA), which is synthesized from aspartate and acetyl-coenzyme A (CoA) in neurons, in the brain and spinal cord between the dmy and control rats. CONCLUSION Our results indicated that the pyruvate dehydrogenase activity might be reduced due to the loss of Mg2+ transport activity in the mitochondria of the dmy rats, suggesting acetyl CoA production might be reduced. The number of oligodendrocytes was well preserved until 7 weeks. It is intriguing that prior to the myelin destruction at 7-8 weeks, disrupted expression of Aspa mRNA and ASPA protein undergoes from early stage of myelinogenesis. These data indicate that ASPA expression would be a useful index to evaluate a function of oligodendrocyte in the dmy rat.
Collapse
|
35
|
Semenova NA, Menshchikov PE, Manzhurtsev AV, Ublinskiy MV, Akhadov TA, Varfolomeev SD. Dynamics of in Vivo Metabolites Concentrations in Posttraumatic Period of Human Brain. 1H MRS Study. DOKL BIOCHEM BIOPHYS 2019; 484:25-28. [PMID: 31012006 DOI: 10.1134/s1607672919010071] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Indexed: 11/23/2022]
Abstract
For the first time the intracellular concentrations of N-acetylaspartate (NAA), aspartate (Asp), and glutamate (Glu) were measured in human brain in vivo, and the effect of severe traumatic brain injury on NAA synthesis in acute and remote posttraumatic phases was revealed. In non-damaged (MRI-negative) lobes the next day after injury, Asp and Glu decreased by 45% and 35%, respectively, while NAA decreased only by 16%. A negative correlation between NAA and Asp/Glu ratio was found. The Glu level returned to the norm long after injury, Asp remained below the norm by 60%, NAA decreased by 65% relative to the norm, and Asp/Glu decreased significantly. The results obtained educe the leading role of neuronal aspartate-malate shuttle in NAA synthesis alterations.
Collapse
Affiliation(s)
- N A Semenova
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 119334, Moscow, Russia.,Semenov Institute of Chemical Physics, Russian Academy of Sciences, 119991, Moscow, Russia.,Clinical and Research Institute of Emergency Pediatric Surgery and Traumatology, 127412, Moscow, Russia
| | - P E Menshchikov
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 119334, Moscow, Russia.,Semenov Institute of Chemical Physics, Russian Academy of Sciences, 119991, Moscow, Russia.,Clinical and Research Institute of Emergency Pediatric Surgery and Traumatology, 127412, Moscow, Russia
| | - A V Manzhurtsev
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 119334, Moscow, Russia. .,Clinical and Research Institute of Emergency Pediatric Surgery and Traumatology, 127412, Moscow, Russia.
| | - M V Ublinskiy
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 119334, Moscow, Russia.,Clinical and Research Institute of Emergency Pediatric Surgery and Traumatology, 127412, Moscow, Russia
| | - T A Akhadov
- Clinical and Research Institute of Emergency Pediatric Surgery and Traumatology, 127412, Moscow, Russia
| | - S D Varfolomeev
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 119334, Moscow, Russia.,Chemical Faculty, Moscow State University, 119991, Moscow, Russia
| |
Collapse
|
36
|
Transcriptional Regulation Factors of the Human Mitochondrial Aspartate/Glutamate Carrier Gene, Isoform 2 ( SLC25A13): USF1 as Basal Factor and FOXA2 as Activator in Liver Cells. Int J Mol Sci 2019; 20:ijms20081888. [PMID: 30995827 PMCID: PMC6515469 DOI: 10.3390/ijms20081888] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 04/12/2019] [Accepted: 04/14/2019] [Indexed: 12/23/2022] Open
Abstract
Mitochondrial carriers catalyse the translocation of numerous metabolites across the inner mitochondrial membrane, playing a key role in different cell functions. For this reason, mitochondrial carrier gene expression needs tight regulation. The human SLC25A13 gene, encoding for the mitochondrial aspartate/glutamate carrier isoform 2 (AGC2), catalyses the electrogenic exchange of aspartate for glutamate plus a proton, thus taking part in many metabolic processes including the malate-aspartate shuttle. By the luciferase (LUC) activity of promoter deletion constructs we identified the putative promoter region, comprising the proximal promoter (-442 bp/-19 bp), as well as an enhancer region (-968 bp/-768 bp). Furthermore, with different approaches, such as in silico promoter analysis, gene silencing and chromatin immunoprecipitation, we identified two transcription factors responsible for SLC25A13 transcriptional regulation: FOXA2 and USF1. USF1 acts as a positive transcription factor which binds to the basal promoter thus ensuring SLC25A13 gene expression in a wide range of tissues. The role of FOXA2 is different, working as an activator in hepatic cells. As a tumour suppressor, FOXA2 could be responsible for SLC25A13 high expression levels in liver and its downregulation in hepatocellular carcinoma (HCC).
Collapse
|
37
|
Juaristi I, Llorente-Folch I, Satrústegui J, Del Arco A. Extracellular ATP and glutamate drive pyruvate production and energy demand to regulate mitochondrial respiration in astrocytes. Glia 2019; 67:759-774. [PMID: 30623988 DOI: 10.1002/glia.23574] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 11/08/2018] [Accepted: 11/13/2018] [Indexed: 12/26/2022]
Abstract
Astrocytes respond to energetic demands by upregulating glycolysis, lactate production, and respiration. This study addresses the role of respiration and calcium regulation of respiration as part of the astrocyte response to the workloads caused by extracellular ATP and glutamate. Extracellular ATP (100 μM to 1 mM) causes a Ca2+ -dependent workload and fall of the cytosolic ATP/ADP ratio which acutely increases astrocytes respiration. Part of this increase is related to a Ca2+ -dependent upregulation of cytosolic pyruvate production. Conversely, glutamate (200 μM) causes a Na+ , but not Ca2+ , dependent workload even though glutamate-induced Ca2+ signals readily reach mitochondria. The glutamate workload triggers a rapid fall in the cytosolic ATP/ADP ratio and stimulation of respiration. These effects are mimicked by D-aspartate a nonmetabolized agonist of the glutamate transporter, but not by a metabotropic glutamate receptor agonist, indicating a major role of Na+ -dependent workload in stimulated respiration. Glutamate-induced increase in respiration is linked to a rapid increase in glycolytic pyruvate production, suggesting that both glutamate and extracellular ATP cause an increase in astrocyte respiration fueled by workload-induced increase in pyruvate production. However, glutamate-induced pyruvate production is partly resistant to glycolysis blockers (iodoacetate), indicating that oxidative consumption of glutamate also contributes to stimulated respiration. As stimulation of respiration by ATP and glutamate are similar and pyruvate production smaller in the first case, the results suggest that the response to extracellular ATP is a Ca2+ -dependent upregulation of respiration added to glycolysis upregulation. The global contribution of astrocyte respiratory responses to brain oxygen consumption is an open question.
Collapse
Affiliation(s)
- Inés Juaristi
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Irene Llorente-Folch
- Department of Physiology & Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland.,Center for Systems Medicine, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Jorgina Satrústegui
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Araceli Del Arco
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain.,Facultad de Ciencias Ambientales y Bioquímica, Centro Regional de Investigaciones Biomédicas, Universidad de Castilla la Mancha, Toledo, Spain
| |
Collapse
|
38
|
Shelton GD, Minor KM, Li K, Naviaux JC, Monk J, Wang L, Guzik E, Guo LT, Porcelli V, Gorgoglione R, Lasorsa FM, Leegwater PJ, Persico AM, Mickelson JR, Palmieri L, Naviaux RK. A Mutation in the Mitochondrial Aspartate/Glutamate Carrier Leads to a More Oxidizing Intramitochondrial Environment and an Inflammatory Myopathy in Dutch Shepherd Dogs. J Neuromuscul Dis 2019; 6:485-501. [PMID: 31594244 PMCID: PMC6918910 DOI: 10.3233/jnd-190421] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Inflammatory myopathies are characterized by infiltration of inflammatory cells into muscle. Typically, immune-mediated disorders such as polymyositis, dermatomyositis and inclusion body myositis are diagnosed. OBJECTIVE A small family of dogs with early onset muscle weakness and inflammatory muscle biopsies were investigated for an underlying genetic cause. METHODS Following the histopathological diagnosis of inflammatory myopathy, mutational analysis including whole genome sequencing, functional transport studies of the mutated and wild-type proteins, and metabolomic analysis were performed. RESULTS Whole genome resequencing identified a pathological variant in the SLC25A12 gene, resulting in a leucine to proline substitution at amino acid 349 in the mitochondrial aspartate-glutamate transporter known as the neuron and muscle specific aspartate glutamate carrier 1 (AGC1). Functionally reconstituting recombinant wild-type and mutant AGC1 into liposomes demonstrated a dramatic decrease in AGC1 transport activity and inability to transfer reducing equivalents from the cytosol into mitochondria. Targeted, broad-spectrum metabolomic analysis from affected and control muscles demonstrated a proinflammatory milieu and strong support for oxidative stress. CONCLUSIONS This study provides the first description of a metabolic mechanism in which ablated mitochondrial glutamate transport markedly reduced the import of reducing equivalents into mitochondria and produced a highly oxidizing and proinflammatory muscle environment and an inflammatory myopathy.
Collapse
Affiliation(s)
- G. Diane Shelton
- Department of Pathology, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Katie M. Minor
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN, USA
| | - Kefeng Li
- The Mitochondrial and Metabolic Disease Center, School of Medicine, University of California San Diego, San Diego, CA, USA
| | - Jane C. Naviaux
- Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Jon Monk
- The Mitochondrial and Metabolic Disease Center, School of Medicine, University of California San Diego, San Diego, CA, USA
| | - Lin Wang
- The Mitochondrial and Metabolic Disease Center, School of Medicine, University of California San Diego, San Diego, CA, USA
| | - Elizabeth Guzik
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN, USA
| | - Ling T. Guo
- Department of Pathology, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Vito Porcelli
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari Aldo Moro, Bari, Italy
| | - Ruggiero Gorgoglione
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari Aldo Moro, Bari, Italy
| | - Francesco M. Lasorsa
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies, Consiglio Nazionale delle Ricerche, Bari, Italy
| | - Peter J. Leegwater
- Department of Clinical Sciences of Companion Animals, Utrecht University, Utrecht, 3508, The Netherlands
| | - Antonio M. Persico
- Interdepartmental Program “Autism 0–90”, “G. Martino” Hospital, University of Messina, Messina, Italy
| | - James R. Mickelson
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN, USA
| | - Luigi Palmieri
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari Aldo Moro, Bari, Italy
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies, Consiglio Nazionale delle Ricerche, Bari, Italy
| | - Robert K. Naviaux
- Department of Pathology, School of Medicine, University of California San Diego, La Jolla, CA, USA
- The Mitochondrial and Metabolic Disease Center, School of Medicine, University of California San Diego, San Diego, CA, USA
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, CA, USA
- Department of Pediatrics, School of Medicine, University of California San Diego, La Jolla, CA, USA
| |
Collapse
|
39
|
Epigenetic upregulation and functional role of the mitochondrial aspartate/glutamate carrier isoform 1 in hepatocellular carcinoma. Biochim Biophys Acta Mol Basis Dis 2019; 1865:38-47. [DOI: 10.1016/j.bbadis.2018.10.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Revised: 10/05/2018] [Accepted: 10/11/2018] [Indexed: 12/12/2022]
|
40
|
Alkan HF, Walter KE, Luengo A, Madreiter-Sokolowski CT, Stryeck S, Lau AN, Al-Zoughbi W, Lewis CA, Thomas CJ, Hoefler G, Graier WF, Madl T, Vander Heiden MG, Bogner-Strauss JG. Cytosolic Aspartate Availability Determines Cell Survival When Glutamine Is Limiting. Cell Metab 2018; 28:706-720.e6. [PMID: 30122555 PMCID: PMC6390946 DOI: 10.1016/j.cmet.2018.07.021] [Citation(s) in RCA: 112] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 05/29/2018] [Accepted: 07/29/2018] [Indexed: 12/23/2022]
Abstract
Mitochondrial function is important for aspartate biosynthesis in proliferating cells. Here, we show that mitochondrial aspartate export via the aspartate-glutamate carrier 1 (AGC1) supports cell proliferation and cellular redox homeostasis. Insufficient cytosolic aspartate delivery leads to cell death when TCA cycle carbon is reduced following glutamine withdrawal and/or glutaminase inhibition. Moreover, loss of AGC1 reduces allograft tumor growth that is further compromised by treatment with the glutaminase inhibitor CB-839. Together, these findings argue that mitochondrial aspartate export sustains cell survival in low-glutamine environments and AGC1 inhibition can synergize with glutaminase inhibition to limit tumor growth.
Collapse
Affiliation(s)
- H Furkan Alkan
- Institute of Biochemistry, Graz University of Technology, Humboldtstrasse 46/III, 8010 Graz, Austria; The Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Katharina E Walter
- Institute of Biochemistry, Graz University of Technology, Humboldtstrasse 46/III, 8010 Graz, Austria
| | - Alba Luengo
- The Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Corina T Madreiter-Sokolowski
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, A-8010 Graz, Austria
| | - Sarah Stryeck
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, A-8010 Graz, Austria
| | - Allison N Lau
- The Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Wael Al-Zoughbi
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Neue Stiftingtalstraße 6, A-8010 Graz, Austria
| | - Caroline A Lewis
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA
| | - Craig J Thomas
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20892, USA; Lymphoid Malignancies Branch, National Cancer Institute, Bethesda, MD 20892, USA
| | - Gerald Hoefler
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Neue Stiftingtalstraße 6, A-8010 Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Wolfgang F Graier
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, A-8010 Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Tobias Madl
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, A-8010 Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Matthew G Vander Heiden
- The Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Dana-Farber Cancer Institute, Boston, MA 02115, USA.
| | - Juliane G Bogner-Strauss
- Institute of Biochemistry, Graz University of Technology, Humboldtstrasse 46/III, 8010 Graz, Austria; BioTechMed-Graz, Graz, Austria.
| |
Collapse
|
41
|
Menshchikov PE, Semenova NA, Manzhurtsev AV, Melnikov IA, Ublinskii MV, Akhadov TA, Varfolomeev SD. Disturbances of Cerebral Metabolism of Aspartate, Glutamate, and N-Acetylaspartate after Traumatic Brain Injury According to 1H Magnetic Resonance Spectroscopy. Biophysics (Nagoya-shi) 2018. [DOI: 10.1134/s0006350918060209] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
|
42
|
Zyśk M, Bielarczyk H, Gul-Hinc S, Dyś A, Gapys B, Ronowska A, Sakowicz-Burkiewicz M, Szutowicz A. Phenotype-Dependent Interactions between N-acetyl-L-Aspartate and Acetyl-CoA in Septal SN56 Cholinergic Cells Exposed to an Excess of Zinc. J Alzheimers Dis 2018; 56:1145-1158. [PMID: 28106547 DOI: 10.3233/jad-160693] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Pyruvate dehydrogenase reaction utilizing glucose-derived pyruvate is an almost exclusive source of acetyl-CoA in different cell mitochondrial compartments of the brain. In neuronal mitochondria, the largest fraction of acetyl-CoA is utilized for energy production and the much smaller one for N-acetyl-L-aspartate (NAA) synthesis. Cholinergic neurons, unlike others, require additional amounts of acetyl-CoA for acetylcholine synthesis. Therefore, several neurotoxic signals, which inhibit pyruvate dehydrogenase, generate deeper shortages of acetyl-CoA and greater mortality of cholinergic neurons than noncholinergic ones. NAA is considered to be a marker of neuronal energy status in neuropathic brains. However, there is no data on putative differential fractional distribution of the acetyl-CoA pool between energy producing and NAA or acetylcholine synthesizing pathways in noncholinergic and cholinergic neurons, respectively. Therefore, the aim of this study was to investigate whether zinc-excess, a common excitotoxic signal, may evoke differential effects on the NAA metabolism in neuronal cells with low and high expression of the cholinergic phenotype. Differentiated SN56 neuronal cells, displaying a high activity of choline acetyltransferase and rates of acetylcholine synthesis, contained lower levels of acetyl-CoA and NAA, being more susceptible to ZnCl2 exposition that the nondifferentiated SN56 or differentiated dopaminergic SHSY5Y neuronal and astroglial C6 cells. Differentiated SN56 accumulated greater amounts of Zn2 + from extracellular space than the other ones, and displayed a stronger suppression of pyruvate dehydrogenase complex activity and acetyl-CoA, NAA, ATP, acetylcholine levels, and loss of viability. These data indicate that the acetyl-CoA synthesizing system in neurons constitutes functional unity with energy generating and NAA or acetylcholine pathways of its utilization, which are uniformly affected by neurotoxic conditions.
Collapse
Affiliation(s)
- Marlena Zyśk
- Department of Laboratory Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | - Hanna Bielarczyk
- Department of Laboratory Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | - Sylwia Gul-Hinc
- Department of Laboratory Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | - Aleksandra Dyś
- Department of Laboratory Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | - Beata Gapys
- Department of Laboratory Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | - Anna Ronowska
- Department of Laboratory Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | | | - Andrzej Szutowicz
- Department of Laboratory Medicine, Medical University of Gdańsk, Gdańsk, Poland
| |
Collapse
|
43
|
Bannerman P, Guo F, Chechneva O, Burns T, Zhu X, Wang Y, Kim B, Singhal NK, McDonough JA, Pleasure D. Brain Nat8l Knockdown Suppresses Spongiform Leukodystrophy in an Aspartoacylase-Deficient Canavan Disease Mouse Model. Mol Ther 2018; 26:793-800. [PMID: 29456021 DOI: 10.1016/j.ymthe.2018.01.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 01/02/2018] [Accepted: 01/06/2018] [Indexed: 10/18/2022] Open
Abstract
Canavan disease, a leukodystrophy caused by loss-of-function ASPA mutations, is characterized by brain dysmyelination, vacuolation, and astrogliosis ("spongiform leukodystrophy"). ASPA encodes aspartoacylase, an oligodendroglial enzyme that cleaves the abundant brain amino acid N-acetyl-L-aspartate (NAA) to L-aspartate and acetate. Aspartoacylase deficiency results in a 50% or greater elevation in brain NAA concentration ([NAAB]). Prior studies showed that homozygous constitutive knockout of Nat8l, the gene encoding the neuronal NAA synthesizing enzyme N-acetyltransferase 8-like, prevents aspartoacylase-deficient mice from developing spongiform leukodystrophy. We now report that brain Nat8l knockdown elicited by intracerebroventricular/intracisternal administration of an adeno-associated viral vector carrying a short hairpin Nat8l inhibitory RNA to neonatal aspartoacylase-deficient AspaNur7/Nur7 mice lowers [NAAB] and suppresses development of spongiform leukodystrophy.
Collapse
Affiliation(s)
- Peter Bannerman
- Institute for Pediatric Regenerative Medicine, University of California, Davis, Sacramento, CA 95817, USA
| | - Fuzheng Guo
- Institute for Pediatric Regenerative Medicine, University of California, Davis, Sacramento, CA 95817, USA
| | - Olga Chechneva
- Institute for Pediatric Regenerative Medicine, University of California, Davis, Sacramento, CA 95817, USA
| | - Travis Burns
- Institute for Pediatric Regenerative Medicine, University of California, Davis, Sacramento, CA 95817, USA
| | - Xiaoqing Zhu
- Cancer Institute, The Affiliated Hospital of Qingdao University, Qingdao, Shandong 266-61, China
| | - Yan Wang
- Institute for Pediatric Regenerative Medicine, University of California, Davis, Sacramento, CA 95817, USA
| | - Bokyung Kim
- Institute for Pediatric Regenerative Medicine, University of California, Davis, Sacramento, CA 95817, USA
| | - Naveen K Singhal
- Department of Biological Sciences and School of Biomedical Sciences, Kent State University, Kent, OH 44242, USA
| | - Jennifer A McDonough
- Department of Biological Sciences and School of Biomedical Sciences, Kent State University, Kent, OH 44242, USA
| | - David Pleasure
- Institute for Pediatric Regenerative Medicine, University of California, Davis, Sacramento, CA 95817, USA.
| |
Collapse
|
44
|
Goubert E, Mircheva Y, Lasorsa FM, Melon C, Profilo E, Sutera J, Becq H, Palmieri F, Palmieri L, Aniksztejn L, Molinari F. Inhibition of the Mitochondrial Glutamate Carrier SLC25A22 in Astrocytes Leads to Intracellular Glutamate Accumulation. Front Cell Neurosci 2017; 11:149. [PMID: 28620281 PMCID: PMC5449474 DOI: 10.3389/fncel.2017.00149] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 05/09/2017] [Indexed: 12/16/2022] Open
Abstract
The solute carrier family 25 (SLC25) drives the import of a large diversity of metabolites into mitochondria, a key cellular structure involved in many metabolic functions. Mutations of the mitochondrial glutamate carrier SLC25A22 (also named GC1) have been identified in early epileptic encephalopathy (EEE) and migrating partial seizures in infancy (MPSI) but the pathophysiological mechanism of GC1 deficiency is still unknown, hampered by the absence of an in vivo model. This carrier is mainly expressed in astrocytes and is the principal gate for glutamate entry into mitochondria. A sufficient supply of energy is essential for the proper function of the brain and mitochondria have a pivotal role in maintaining energy homeostasis. In this work, we wanted to study the consequences of GC1 absence in an in vitro model in order to understand if glutamate catabolism and/or mitochondrial function could be affected. First, short hairpin RNA (shRNA) designed to specifically silence GC1 were validated in rat C6 glioma cells. Silencing GC1 in C6 resulted in a reduction of the GC1 mRNA combined with a decrease of the mitochondrial glutamate carrier activity. Then, primary astrocyte cultures were prepared and transfected with shRNA-GC1 or mismatch-RNA (mmRNA) constructs using the Neon® Transfection System in order to target a high number of primary astrocytes, more than 64%. Silencing GC1 in primary astrocytes resulted in a reduced nicotinamide adenine dinucleotide (Phosphate) (NAD(P)H) formation upon glutamate stimulation. We also observed that the mitochondrial respiratory chain (MRC) was functional after glucose stimulation but not activated by glutamate, resulting in a lower level of cellular adenosine triphosphate (ATP) in silenced astrocytes compared to control cells. Moreover, GC1 inactivation resulted in an intracellular glutamate accumulation. Our results show that mitochondrial glutamate transport via GC1 is important in sustaining glutamate homeostasis in astrocytes. Main Points:The mitochondrial respiratory chain is functional in absence of GC1 Lack of glutamate oxidation results in a lower global ATP level Lack of mitochondrial glutamate transport results in intracellular glutamate accumulation
Collapse
Affiliation(s)
| | - Yanina Mircheva
- INMED, INSERM, Aix-Marseille UniversitéMarseille, France.,Centre De Recherche De L'Institut Universitaire En Santé Mentale de QuébecQuebec City, QC, Canada
| | - Francesco M Lasorsa
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, and CNR Institute of Biomembranes, Bioenergetics and Molecular BiotechnologiesBari, Italy
| | | | - Emanuela Profilo
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, and CNR Institute of Biomembranes, Bioenergetics and Molecular BiotechnologiesBari, Italy
| | - Julie Sutera
- INMED, INSERM, Aix-Marseille UniversitéMarseille, France
| | - Hélène Becq
- INMED, INSERM, Aix-Marseille UniversitéMarseille, France
| | - Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, and CNR Institute of Biomembranes, Bioenergetics and Molecular BiotechnologiesBari, Italy
| | - Luigi Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, and CNR Institute of Biomembranes, Bioenergetics and Molecular BiotechnologiesBari, Italy
| | | | | |
Collapse
|
45
|
Juaristi I, García-Martín ML, Rodrigues TB, Satrústegui J, Llorente-Folch I, Pardo B. ARALAR/AGC1 deficiency, a neurodevelopmental disorder with severe impairment of neuronal mitochondrial respiration, does not produce a primary increase in brain lactate. J Neurochem 2017; 142:132-139. [PMID: 28429368 DOI: 10.1111/jnc.14047] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 03/07/2017] [Accepted: 04/07/2017] [Indexed: 12/28/2022]
Abstract
ARALAR/AGC1 (aspartate-glutamate mitochondrial carrier 1) is an important component of the NADH malate-aspartate shuttle (MAS). AGC1-deficiency is a rare disease causing global cerebral hypomyelination, developmental arrest, hypotonia, and epilepsy (OMIM ID #612949); the aralar-KO mouse recapitulates the major findings in humans. This study was aimed at understanding the impact of ARALAR-deficiency in brain lactate levels as a biomarker. We report that lactate was equally abundant in wild-type and aralar-KO mouse brain in vivo at postnatal day 17. We find that lactate production upon mitochondrial blockade depends on up-regulation of lactate formation in astrocytes rather than in neurons. However, ARALAR-deficiency decreased cell respiration in neurons, not astrocytes, which maintained unchanged respiration and lactate production. As the primary site of ARALAR-deficiency is neuronal, this explains the lack of accumulation of brain lactate in ARALAR-deficiency in humans and mice. On the other hand, we find that the cytosolic and mitochondrial components of the glycerol phosphate shuttle are present in astrocytes with similar activities. This suggests that glycerol phosphate shuttle is the main NADH shuttle in astrocytes and explains the absence of effects of ARALAR-deficiency in these cells.
Collapse
Affiliation(s)
- Inés Juaristi
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, Madrid, Spain.,CIBER de Enfermedades Raras (CIBERER), Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD); Universidad Autónoma de Madrid, Madrid, Spain
| | - María L García-Martín
- Laboratory of Metabolomics and Molecular Imaging, BIONAND, Andalusian Centre for Nanomedicine and Biotechnology (Junta de Andalucía, Universidad de Málaga), Malaga, Spain
| | - Tiago B Rodrigues
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK.,Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Jorgina Satrústegui
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, Madrid, Spain.,CIBER de Enfermedades Raras (CIBERER), Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD); Universidad Autónoma de Madrid, Madrid, Spain
| | - Irene Llorente-Folch
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, Madrid, Spain.,CIBER de Enfermedades Raras (CIBERER), Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD); Universidad Autónoma de Madrid, Madrid, Spain
| | - Beatriz Pardo
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, Madrid, Spain.,CIBER de Enfermedades Raras (CIBERER), Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD); Universidad Autónoma de Madrid, Madrid, Spain
| |
Collapse
|
46
|
L-Lactate-Mediated Neuroprotection against Glutamate-Induced Excitotoxicity Requires ARALAR/AGC1. J Neurosci 2016; 36:4443-56. [PMID: 27098689 DOI: 10.1523/jneurosci.3691-15.2016] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 02/20/2016] [Indexed: 01/20/2023] Open
Abstract
UNLABELLED ARALAR/AGC1/Slc25a12, the aspartate-glutamate carrier from brain mitochondria, is the regulatory step in the malate-aspartate NADH shuttle, MAS. MAS is used to oxidize cytosolic NADH in mitochondria, a process required to maintain oxidative glucose utilization. The role of ARALAR was analyzed in two paradigms of glutamate-induced excitotoxicity in cortical neurons: glucose deprivation and acute glutamate stimulation. ARALAR deficiency did not aggravate glutamate-induced neuronal death in vitro, although glutamate-stimulated respiration was impaired. In contrast, the presence of L-lactate as an additional source protected against glutamate-induced neuronal death in control, but not ARALAR-deficient neurons.l-Lactate supplementation increased glutamate-stimulated respiration partially prevented the decrease in the cytosolic ATP/ADP ratio induced by glutamate and substantially diminished mitochondrial accumulation of 8-oxoguanosine, a marker of reactive oxygen species production, only in the presence, but not the absence, of ARALAR. In addition,l-lactate potentiated glutamate-induced increase in cytosolic Ca(2+), in a way independent of the presence of ARALAR. Interestingly,in vivo, the loss of half-a-dose of ARALAR in aralar(+/-)mice enhanced kainic acid-induced seizures and neuronal damage with respect to control animals, in a model of excitotoxicity in which increased L-lactate levels and L-lactate consumption have been previously proven. These results suggest that,in vivo, an inefficient operation of the shuttle in the aralar hemizygous mice prevents the protective role of L-lactate on glutamate excitotoxiciy and that the entry and oxidation of L-lactate through ARALAR-MAS pathway is required for its neuroprotective function. SIGNIFICANCE STATEMENT Lactate now stands as a metabolite necessary for multiple functions in the brain and is an alternative energy source during excitotoxic brain injury. Here we find that the absence of a functional malate-aspartate NADH shuttle caused by aralar/AGC1 disruption causes a block in lactate utilization by neurons, which prevents the protective role of lactate on excitotoxicity, but not glutamate excitotoxicity itself. Thus, failure to use lactate is detrimental and is possibly responsible for the exacerbated in vivo excitotoxicity in aralar(+/-)mice.
Collapse
|
47
|
Contreras L, Rial E, Cerdan S, Satrustegui J. Uncoupling Protein 2 (UCP2) Function in the Brain as Revealed by the Cerebral Metabolism of (1–13C)-Glucose. Neurochem Res 2016; 42:108-114. [DOI: 10.1007/s11064-016-1999-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 06/30/2016] [Accepted: 07/02/2016] [Indexed: 12/15/2022]
|
48
|
Dienel GA, Cruz NF. Aerobic glycolysis during brain activation: adrenergic regulation and influence of norepinephrine on astrocytic metabolism. J Neurochem 2016; 138:14-52. [DOI: 10.1111/jnc.13630] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 03/24/2016] [Accepted: 03/31/2016] [Indexed: 12/17/2022]
Affiliation(s)
- Gerald A. Dienel
- Department of Cell Biology and Physiology; University of New Mexico; Albuquerque; New Mexico USA
- Department of Neurology; University of Arkansas for Medical Sciences; Little Rock Arkansas USA
| | - Nancy F. Cruz
- Department of Neurology; University of Arkansas for Medical Sciences; Little Rock Arkansas USA
| |
Collapse
|
49
|
Amoedo ND, Punzi G, Obre E, Lacombe D, De Grassi A, Pierri CL, Rossignol R. AGC1/2, the mitochondrial aspartate-glutamate carriers. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:2394-412. [PMID: 27132995 DOI: 10.1016/j.bbamcr.2016.04.011] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 03/28/2016] [Accepted: 04/08/2016] [Indexed: 10/21/2022]
Abstract
In this review we discuss the structure and functions of the aspartate/glutamate carriers (AGC1-aralar and AGC2-citrin). Those proteins supply the aspartate synthesized within mitochondrial matrix to the cytosol in exchange for glutamate and a proton. A structure of an AGC carrier is not available yet but comparative 3D models were proposed. Moreover, transport assays performed by using the recombinant AGC1 and AGC2, reconstituted into liposome vesicles, allowed to explore the kinetics of those carriers and to reveal their specific transport properties. AGCs participate to a wide range of cellular functions, as the control of mitochondrial respiration, calcium signaling and antioxydant defenses. AGC1 might also play peculiar tissue-specific functions, as it was found to participate to cell-to-cell metabolic symbiosis in the retina. On the other hand, AGC1 is involved in the glutamate-mediated excitotoxicity in neurons and AGC gene or protein alterations were discovered in rare human diseases. Accordingly, a mice model of AGC1 gene knock-out presented with growth delay and generalized tremor, with myelinisation defects. More recently, AGC was proposed to play a crucial role in tumor metabolism as observed from metabolomic studies showing that the asparate exported from the mitochondrion by AGC1 is employed in the regeneration of cytosolic glutathione. Therefore, given the central role of AGCs in cell metabolism and human pathology, drug screening are now being developed to identify pharmacological modulators of those carriers. This article is part of a Special Issue entitled: Mitochondrial Channels edited by Pierre Sonveaux, Pierre Maechler and Jean-Claude Martinou.
Collapse
Affiliation(s)
- N D Amoedo
- Univ. Bordeaux, U1211, Bordeaux, France; INSERM, U1211, Bordeaux, France; Instituto de Bioquímica Médica Leopoldo De Meis, UFRJ, Rio de Janeiro, Brazil
| | - G Punzi
- Univ. Bordeaux, U1211, Bordeaux, France; INSERM, U1211, Bordeaux, France; Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari
| | - E Obre
- Univ. Bordeaux, U1211, Bordeaux, France; INSERM, U1211, Bordeaux, France
| | - D Lacombe
- Univ. Bordeaux, U1211, Bordeaux, France; INSERM, U1211, Bordeaux, France
| | - A De Grassi
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari
| | - C L Pierri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari.
| | - R Rossignol
- Univ. Bordeaux, U1211, Bordeaux, France; INSERM, U1211, Bordeaux, France.
| |
Collapse
|
50
|
Del Arco A, Contreras L, Pardo B, Satrustegui J. Calcium regulation of mitochondrial carriers. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:2413-21. [PMID: 27033520 DOI: 10.1016/j.bbamcr.2016.03.024] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 03/23/2016] [Accepted: 03/23/2016] [Indexed: 11/16/2022]
Abstract
Mitochondrial function is regulated by calcium. In addition to the long known effects of matrix Ca(2+), regulation of metabolite transport by extramitochondrial Ca(2+) represents an alternative Ca(2+)-dependent mechanism to regulate mitochondrial function. The Ca(2+) regulated mitochondrial transporters (CaMCs) are well suited for that role, as they contain long N-terminal extensions harboring EF-hand Ca(2+) binding domains facing the intermembrane space. They fall in two groups, the aspartate/glutamate exchangers, AGCs, major components of the NADH malate aspartate shuttle (MAS) and urea cycle, and the ATP-Mg(2+)/Pi exchangers or short CaMCs (APCs or SCaMCs). The AGCs are activated by relatively low Ca(2+) levels only slightly higher than resting Ca(2+), whereas all SCaMCs studied so far require strong Ca(2+) signals, above micromolar, for activation. In addition, AGCs are not strictly Ca(2+) dependent, being active even in Ca(2+)-free conditions. Thus, AGCs are well suited to respond to small Ca(2+) signals and that do not reach mitochondria. In contrast, ATP-Mg(2+)/Pi carriers are inactive in Ca(2+) free conditions and activation requires Ca(2+) signals that will also activate the calcium uniporter (MCU). By changing the net content of adenine nucleotides of the matrix upon activation, SCaMCs regulate the activity of the permeability transition pore, and the Ca(2+) retention capacity of mitochondria (CRC), two functions synergizing with those of the MCU. The different Ca(2+) activation properties of the two CaMCs are discussed in relation to their newly obtained structures. This article is part of a Special Issue entitled: Mitochondrial Channels edited by Pierre Sonveaux, Pierre Maechler and Jean-Claude Martinou.
Collapse
Affiliation(s)
- Araceli Del Arco
- Facultad de Ciencias Ambientales y Bioquímica, Centro RegionaI de Investigaciones Biomédicas, Universidad de Castilla la Mancha, Toledo 45071, Spain; CIBER de Enfermedades Raras (CIBERER), ISCIII, Madrid, Spain; Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Laura Contreras
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain; CIBER de Enfermedades Raras (CIBERER), ISCIII, Madrid, Spain; Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Beatriz Pardo
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain; CIBER de Enfermedades Raras (CIBERER), ISCIII, Madrid, Spain; Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Jorgina Satrustegui
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain; CIBER de Enfermedades Raras (CIBERER), ISCIII, Madrid, Spain; Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain.
| |
Collapse
|