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Thomas CI, Ryan MA, McNabb MC, Kamasawa N, Scholl B. Astrocyte coverage of excitatory synapses correlates to measures of synapse structure and function in ferret primary visual cortex. Glia 2024. [PMID: 38856149 DOI: 10.1002/glia.24582] [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: 12/08/2023] [Revised: 05/25/2024] [Accepted: 06/02/2024] [Indexed: 06/11/2024]
Abstract
Most excitatory synapses in the mammalian brain are contacted or ensheathed by astrocyte processes, forming tripartite synapses. Astrocytes are thought to be critical regulators of the structural and functional dynamics of synapses. While the degree of synaptic coverage by astrocytes is known to vary across brain regions and animal species, the reason for and implications of this variability remains unknown. Further, how astrocyte coverage of synapses relates to in vivo functional properties of individual synapses has not been investigated. Here, we characterized astrocyte coverage of synapses of pyramidal neurons in the ferret visual cortex and, using correlative light and electron microscopy, examined their relationship to synaptic strength and sensory-evoked Ca2+ activity. Nearly, all synapses were contacted by astrocytes, and most were contacted along the axon-spine interface. Structurally, we found that the degree of synaptic astrocyte coverage directly scaled with synapse size and postsynaptic density complexity. Functionally, we found that the amount of astrocyte coverage scaled with how selectively a synapse responds to a particular visual stimulus and, at least for the largest synapses, scaled with the reliability of visual stimuli to evoke postsynaptic Ca2+ events. Our study shows astrocyte coverage is highly correlated with structural metrics of synaptic strength of excitatory synapses in the visual cortex and demonstrates a previously unknown relationship between astrocyte coverage and reliable sensory activation.
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Affiliation(s)
- Connon I Thomas
- Electron Microscopy Core Facility, Max Planck Florida Institute for Neuroscience, Jupiter, Florida, USA
| | - Melissa A Ryan
- Electron Microscopy Core Facility, Max Planck Florida Institute for Neuroscience, Jupiter, Florida, USA
| | - Micaiah C McNabb
- Electron Microscopy Core Facility, Max Planck Florida Institute for Neuroscience, Jupiter, Florida, USA
| | - Naomi Kamasawa
- Electron Microscopy Core Facility, Max Planck Florida Institute for Neuroscience, Jupiter, Florida, USA
| | - Benjamin Scholl
- Department of Physiology and Biophysics, University of Colorado Denver, Aurora, Colorado, USA
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2
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Bredvik K, Liu C, Ryan TA. Characterization of β-Hydroxybutyrate as a Cell Autonomous Fuel for Active Excitatory and Inhibitory Neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.08.598077. [PMID: 38895313 PMCID: PMC11185772 DOI: 10.1101/2024.06.08.598077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
The ketogenic diet is an effective treatment for drug-resistant epilepsy, but the therapeutic mechanisms are poorly understood. Although ketones are able to fuel the brain, it is not known whether ketones are directly metabolized by neurons on a time scale sufficiently rapid to fuel the bioenergetic demands of sustained synaptic transmission. Here, we show that nerve terminals can use the ketone β-hydroxybutyrate in a cell- autonomous fashion to support neurotransmission in both excitatory and inhibitory nerve terminals and that this flexibility relies on Ca 2+ dependent upregulation of mitochondrial metabolism. Using a genetically encoded ATP sensor, we show that inhibitory axons fueled by ketones sustain much higher ATP levels under steady state conditions than excitatory axons, but that the kinetics of ATP production following activity are slower when using ketones as fuel compared to lactate/pyruvate for both excitatory and inhibitory neurons. Significance Statement The ketogenic diet is a standard treatment for drug resistant epilepsy, but the mechanism of treatment efficacy is largely unknown. Changes to excitatory and inhibitory balance is one hypothesized mechanism. Here, we determine that ATP levels are differentially higher in inhibitory neurons compared to excitatory neurons, suggesting that greater mitochondrial ATP production in inhibitory neurons could be one mechanism mediating therapeutic benefit. Further, our studies of ketone metabolism by synaptic mitochondria should inform management of side effects and risks associated with ketogenic diet treatments. These results provide novel insights that clarify the role of ketones at the cellular level in ketogenic diet treatment for intractable epilepsy and inform the use of ketogenic diets for neurologic and psychiatric conditions more broadly.
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3
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Coukos R, Krainc D. Key genes and convergent pathogenic mechanisms in Parkinson disease. Nat Rev Neurosci 2024; 25:393-413. [PMID: 38600347 DOI: 10.1038/s41583-024-00812-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/18/2024] [Indexed: 04/12/2024]
Abstract
Parkinson disease (PD) is a neurodegenerative disorder marked by the preferential dysfunction and death of dopaminergic neurons in the substantia nigra. The onset and progression of PD is influenced by a diversity of genetic variants, many of which lack functional characterization. To identify the most high-yield targets for therapeutic intervention, it is important to consider the core cellular compartments and functional pathways upon which the varied forms of pathogenic dysfunction may converge. Here, we review several key PD-linked proteins and pathways, focusing on the mechanisms of their potential convergence in disease pathogenesis. These dysfunctions primarily localize to a subset of subcellular compartments, including mitochondria, lysosomes and synapses. We discuss how these pathogenic mechanisms that originate in different cellular compartments may coordinately lead to cellular dysfunction and neurodegeneration in PD.
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Affiliation(s)
- Robert Coukos
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Dimitri Krainc
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
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4
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Stykel MG, Ryan SD. Network analysis of S-nitrosylated synaptic proteins demonstrates unique roles in health and disease. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119720. [PMID: 38582237 DOI: 10.1016/j.bbamcr.2024.119720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 03/24/2024] [Accepted: 03/27/2024] [Indexed: 04/08/2024]
Abstract
Nitric oxide can covalently modify cysteine thiols on target proteins to alter that protein's function in a process called S-nitrosylation (SNO). S-nitrosylation of synaptic proteins plays an integral part in neurotransmission. Here we review the function of the SNO-proteome at the synapse and whether clusters of SNO-modification may predict synaptic dysfunction associated with disease. We used a systematic search strategy to concatenate SNO-proteomic datasets from normal human or murine brain samples. Identified SNO-modified proteins were then filtered against proteins reported in the Synaptome Database, which provides a detailed and experimentally verified annotation of all known synaptic proteins. Subsequently, we performed an unbiased network analysis of all known SNO-synaptic proteins to identify clusters of SNO proteins commonly involved in biological processes or with known disease associations. The resulting SNO networks were significantly enriched in biological processes related to metabolism, whereas significant gene-disease associations were related to Schizophrenia, Alzheimer's, Parkinson's and Huntington's disease. Guided by an unbiased network analysis, the current review presents a thorough discussion of how clustered changes to the SNO-proteome influence health and disease.
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Affiliation(s)
- Morgan G Stykel
- Department of Molecular and Cellular Biology, The University of Guelph, Guelph, ON, Canada
| | - Scott D Ryan
- Department of Molecular and Cellular Biology, The University of Guelph, Guelph, ON, Canada; Hotchkiss Brain Institute, Department of Clinical Neuroscience, University of Calgary, Calgary, AB, Canada.
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5
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Myeong J, Stunault MI, Klyachko VA, Ashrafi G. Metabolic regulation of single synaptic vesicle exo- and endocytosis in hippocampal synapses. Cell Rep 2024; 43:114218. [PMID: 38758651 DOI: 10.1016/j.celrep.2024.114218] [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: 11/13/2023] [Revised: 02/26/2024] [Accepted: 04/25/2024] [Indexed: 05/19/2024] Open
Abstract
Glucose has long been considered a primary energy source for synaptic function. However, it remains unclear to what extent alternative fuels, such as lactate/pyruvate, contribute to powering synaptic transmission. By detecting individual release events in hippocampal synapses, we find that mitochondrial ATP production regulates basal vesicle release probability and release location within the active zone (AZ), evoked by single action potentials. Mitochondrial inhibition shifts vesicle release closer to the AZ center and alters the efficiency of vesicle retrieval by increasing the occurrence of ultrafast endocytosis. Furthermore, we uncover that terminals can use oxidative fuels to maintain the vesicle cycle during trains of activity. Mitochondria are sparsely distributed along hippocampal axons, and we find that terminals containing mitochondria display enhanced vesicle release and reuptake during high-frequency trains. Our findings suggest that mitochondria not only regulate several fundamental features of synaptic transmission but may also contribute to modulation of short-term synaptic plasticity.
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Affiliation(s)
- Jongyun Myeong
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Marion I Stunault
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Vitaly A Klyachko
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - Ghazaleh Ashrafi
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA; Needleman Center for Neurometabolism and Axonal Therapeutics, Washington University School of Medicine, St. Louis, MO 63110, USA.
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Marvin JS, Kokotos AC, Kumar M, Pulido C, Tkachuk AN, Yao JS, Brown TA, Ryan TA. iATPSnFR2: A high-dynamic-range fluorescent sensor for monitoring intracellular ATP. Proc Natl Acad Sci U S A 2024; 121:e2314604121. [PMID: 38748581 PMCID: PMC11126915 DOI: 10.1073/pnas.2314604121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 04/10/2024] [Indexed: 05/27/2024] Open
Abstract
We developed a significantly improved genetically encoded quantitative adenosine triphosphate (ATP) sensor to provide real-time dynamics of ATP levels in subcellular compartments. iATPSnFR2 is a variant of iATPSnFR1, a previously developed sensor that has circularly permuted superfolder green fluorescent protein (GFP) inserted between the ATP-binding helices of the ε-subunit of a bacterial F0-F1 ATPase. Optimizing the linkers joining the two domains resulted in a ~fivefold to sixfold improvement in the dynamic range compared to the previous-generation sensor, with excellent discrimination against other analytes, and affinity variants varying from 4 µM to 500 µM. A chimeric version of this sensor fused to either the HaloTag protein or a suitable spectrally separated fluorescent protein provides an optional ratiometric readout allowing comparisons of ATP across cellular regions. Subcellular targeting the sensor to nerve terminals reveals previously uncharacterized single-synapse metabolic signatures, while targeting to the mitochondrial matrix allowed direct quantitative probing of oxidative phosphorylation dynamics.
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Affiliation(s)
| | - Alexandros C. Kokotos
- Department of Biochemistry, Weill Cornell Medicine, New York, NY10065
- Aligning Science Across Parkinson’s Collaborative Research Network, Chevy Chase, MD20815
| | - Mukesh Kumar
- Department of Biochemistry, Weill Cornell Medicine, New York, NY10065
| | - Camila Pulido
- Department of Biochemistry, Weill Cornell Medicine, New York, NY10065
- Aligning Science Across Parkinson’s Collaborative Research Network, Chevy Chase, MD20815
| | | | | | | | - Timothy A. Ryan
- HHMI, Ashburn, VA20147
- Department of Biochemistry, Weill Cornell Medicine, New York, NY10065
- Aligning Science Across Parkinson’s Collaborative Research Network, Chevy Chase, MD20815
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Leitz J, Wang C, Esquivies L, Pfuetzner RA, Peters JJ, Couoh-Cardel S, Wang AL, Brunger AT. Beyond the MUN domain, Munc13 controls priming and depriming of synaptic vesicles. Cell Rep 2024; 43:114026. [PMID: 38809756 DOI: 10.1016/j.celrep.2024.114026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 02/20/2024] [Accepted: 03/15/2024] [Indexed: 05/31/2024] Open
Abstract
Synaptic vesicle docking and priming are dynamic processes. At the molecular level, SNAREs (soluble NSF attachment protein receptors), synaptotagmins, and other factors are critical for Ca2+-triggered vesicle exocytosis, while disassembly factors, including NSF (N-ethylmaleimide-sensitive factor) and α-SNAP (soluble NSF attachment protein), disassemble and recycle SNAREs and antagonize fusion under some conditions. Here, we introduce a hybrid fusion assay that uses synaptic vesicles isolated from mouse brains and synthetic plasma membrane mimics. We included Munc18, Munc13, complexin, NSF, α-SNAP, and an ATP-regeneration system and maintained them continuously-as in the neuron-to investigate how these opposing processes yield fusogenic synaptic vesicles. In this setting, synaptic vesicle association is reversible, and the ATP-regeneration system produces the most synchronous Ca2+-triggered fusion, suggesting that disassembly factors perform quality control at the early stages of synaptic vesicle association to establish a highly fusogenic state. We uncovered a functional role for Munc13 ancillary to the MUN domain that alleviates an α-SNAP-dependent inhibition of Ca2+-triggered fusion.
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Affiliation(s)
- Jeremy Leitz
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA; Department of Structural Biology, Stanford University, Stanford, CA, USA; Department of Photon Science, Stanford University, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Chuchu Wang
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA; Department of Structural Biology, Stanford University, Stanford, CA, USA; Department of Photon Science, Stanford University, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Luis Esquivies
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA; Department of Structural Biology, Stanford University, Stanford, CA, USA; Department of Photon Science, Stanford University, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Richard A Pfuetzner
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA; Department of Structural Biology, Stanford University, Stanford, CA, USA; Department of Photon Science, Stanford University, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - John Jacob Peters
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA; Department of Structural Biology, Stanford University, Stanford, CA, USA; Department of Photon Science, Stanford University, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Sergio Couoh-Cardel
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA; Department of Structural Biology, Stanford University, Stanford, CA, USA; Department of Photon Science, Stanford University, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Austin L Wang
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA; Department of Structural Biology, Stanford University, Stanford, CA, USA; Department of Photon Science, Stanford University, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Axel T Brunger
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA; Department of Structural Biology, Stanford University, Stanford, CA, USA; Department of Photon Science, Stanford University, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA.
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8
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Kann O. Lactate as a supplemental fuel for synaptic transmission and neuronal network oscillations: Potentials and limitations. J Neurochem 2024; 168:608-631. [PMID: 37309602 DOI: 10.1111/jnc.15867] [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: 02/28/2023] [Revised: 05/15/2023] [Accepted: 05/18/2023] [Indexed: 06/14/2023]
Abstract
Lactate shuttled from the blood circulation, astrocytes, oligodendrocytes or even activated microglia (resident macrophages) to neurons has been hypothesized to represent a major source of pyruvate compared to what is normally produced endogenously by neuronal glucose metabolism. However, the role of lactate oxidation in fueling neuronal signaling associated with complex cortex function, such as perception, motor activity, and memory formation, is widely unclear. This issue has been experimentally addressed using electrophysiology in hippocampal slice preparations (ex vivo) that permit the induction of different neural network activation states by electrical stimulation, optogenetic tools or receptor ligand application. Collectively, these studies suggest that lactate in the absence of glucose (lactate only) impairs gamma (30-70 Hz) and theta-gamma oscillations, which feature high energy demand revealed by the cerebral metabolic rate of oxygen (CMRO2, set to 100%). The impairment comprises oscillation attenuation or moderate neural bursts (excitation-inhibition imbalance). The bursting is suppressed by elevating the glucose fraction in energy substrate supply. By contrast, lactate can retain certain electric stimulus-induced neural population responses and intermittent sharp wave-ripple activity that features lower energy expenditure (CMRO2 of about 65%). Lactate utilization increases the oxygen consumption by about 9% during sharp wave-ripples reflecting enhanced adenosine-5'-triphosphate (ATP) synthesis by oxidative phosphorylation in mitochondria. Moreover, lactate attenuates neurotransmission in glutamatergic pyramidal cells and fast-spiking, γ-aminobutyric acid (GABA)ergic interneurons by reducing neurotransmitter release from presynaptic terminals. By contrast, the generation and propagation of action potentials in the axon is regular. In conclusion, lactate is less effective than glucose and potentially detrimental during neural network rhythms featuring high energetic costs, likely through the lack of some obligatory ATP synthesis by aerobic glycolysis at excitatory and inhibitory synapses. High lactate/glucose ratios might contribute to central fatigue, cognitive impairment, and epileptic seizures partially seen, for instance, during exhaustive physical exercise, hypoglycemia and neuroinflammation.
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Affiliation(s)
- Oliver Kann
- Institute of Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany
- Interdisciplinary Center for Neurosciences (IZN), University of Heidelberg, Heidelberg, Germany
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Panagaki T, Janickova L, Petrovic D, Zuhra K, Ditrói T, Jurányi EP, Bremer O, Ascenção K, Philipp TM, Nagy P, Filipovic MR, Szabo C. Neurobehavioral dysfunction in a mouse model of Down syndrome: upregulation of cystathionine β-synthase, H 2S overproduction, altered protein persulfidation, synaptic dysfunction, endoplasmic reticulum stress, and autophagy. GeroScience 2024:10.1007/s11357-024-01146-8. [PMID: 38558215 DOI: 10.1007/s11357-024-01146-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 03/21/2024] [Indexed: 04/04/2024] Open
Abstract
Down syndrome (DS) is a genetic condition where the person is born with an extra chromosome 21. DS is associated with accelerated aging; people with DS are prone to age-related neurological conditions including an early-onset Alzheimer's disease. Using the Dp(17)3Yey/ + mice, which overexpresses a portion of mouse chromosome 17, which encodes for the transsulfuration enzyme cystathionine β-synthase (CBS), we investigated the functional role of the CBS/hydrogen sulfide (H2S) pathway in the pathogenesis of neurobehavioral dysfunction in DS. The data demonstrate that CBS is higher in the brain of the DS mice than in the brain of wild-type mice, with primary localization in astrocytes. DS mice exhibited impaired recognition memory and spatial learning, loss of synaptosomal function, endoplasmic reticulum stress, and autophagy. Treatment of mice with aminooxyacetate, a prototypical CBS inhibitor, improved neurobehavioral function, reduced the degree of reactive gliosis in the DS brain, increased the ability of the synaptosomes to generate ATP, and reduced endoplasmic reticulum stress. H2S levels in the brain of DS mice were higher than in wild-type mice, but, unexpectedly, protein persulfidation was decreased. Many of the above alterations were more pronounced in the female DS mice. There was a significant dysregulation of metabolism in the brain of DS mice, which affected amino acid, carbohydrate, lipid, endocannabinoid, and nucleotide metabolites; some of these alterations were reversed by treatment of the mice with the CBS inhibitor. Thus, the CBS/H2S pathway contributes to the pathogenesis of neurological dysfunction in DS in the current animal model.
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Affiliation(s)
- Theodora Panagaki
- Chair of Pharmacology, Section of Science and Medicine, University of Fribourg, Fribourg, Switzerland
| | - Lucia Janickova
- Chair of Pharmacology, Section of Science and Medicine, University of Fribourg, Fribourg, Switzerland
| | - Dunja Petrovic
- Leibniz-Institut Für Analytische Wissenschaften-ISAS-E.V., Dortmund, Germany
| | - Karim Zuhra
- Chair of Pharmacology, Section of Science and Medicine, University of Fribourg, Fribourg, Switzerland
| | - Tamás Ditrói
- Department of Molecular Immunology and Toxicology and the National Tumor Biology Laboratory, National Institute of Oncology, Budapest, Hungary
| | - Eszter P Jurányi
- Department of Molecular Immunology and Toxicology and the National Tumor Biology Laboratory, National Institute of Oncology, Budapest, Hungary
- Doctoral School of Semmelweis University, Semmelweis University, Budapest, Hungary
| | - Olivier Bremer
- Chair of Pharmacology, Section of Science and Medicine, University of Fribourg, Fribourg, Switzerland
| | - Kelly Ascenção
- Chair of Pharmacology, Section of Science and Medicine, University of Fribourg, Fribourg, Switzerland
| | - Thilo M Philipp
- Chair of Pharmacology, Section of Science and Medicine, University of Fribourg, Fribourg, Switzerland
| | - Péter Nagy
- Department of Molecular Immunology and Toxicology and the National Tumor Biology Laboratory, National Institute of Oncology, Budapest, Hungary
- Department of Anatomy and Histology, HUN-REN-UVMB Laboratory of Redox Biology Research Group, University of Veterinary Medicine, Budapest, Hungary
- Chemistry Institute, University of Debrecen, Debrecen, Hungary
| | - Milos R Filipovic
- Leibniz-Institut Für Analytische Wissenschaften-ISAS-E.V., Dortmund, Germany
| | - Csaba Szabo
- Chair of Pharmacology, Section of Science and Medicine, University of Fribourg, Fribourg, Switzerland.
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Lanfranchi M, Yandiev S, Meyer-Dilhet G, Ellouze S, Kerkhofs M, Dos Reis R, Garcia A, Blondet C, Amar A, Kneppers A, Polvèche H, Plassard D, Foretz M, Viollet B, Sakamoto K, Mounier R, Bourgeois CF, Raineteau O, Goillot E, Courchet J. The AMPK-related kinase NUAK1 controls cortical axons branching by locally modulating mitochondrial metabolic functions. Nat Commun 2024; 15:2487. [PMID: 38514619 PMCID: PMC10958033 DOI: 10.1038/s41467-024-46146-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 02/15/2024] [Indexed: 03/23/2024] Open
Abstract
The cellular mechanisms underlying axonal morphogenesis are essential to the formation of functional neuronal networks. We previously identified the autism-linked kinase NUAK1 as a central regulator of axon branching through the control of mitochondria trafficking. However, (1) the relationship between mitochondrial position, function and axon branching and (2) the downstream effectors whereby NUAK1 regulates axon branching remain unknown. Here, we report that mitochondria recruitment to synaptic boutons supports collateral branches stabilization rather than formation in mouse cortical neurons. NUAK1 deficiency significantly impairs mitochondrial metabolism and axonal ATP concentration, and upregulation of mitochondrial function is sufficient to rescue axonal branching in NUAK1 null neurons in vitro and in vivo. Finally, we found that NUAK1 regulates axon branching through the mitochondria-targeted microprotein BRAWNIN. Our results demonstrate that NUAK1 exerts a dual function during axon branching through its ability to control mitochondrial distribution and metabolic activity.
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Affiliation(s)
- Marine Lanfranchi
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Inserm, Physiopathologie et Génétique du Neurone et du Muscle, UMR5261, U1315, Institut NeuroMyoGène, 69008, Lyon, France
| | - Sozerko Yandiev
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Inserm, Physiopathologie et Génétique du Neurone et du Muscle, UMR5261, U1315, Institut NeuroMyoGène, 69008, Lyon, France
| | - Géraldine Meyer-Dilhet
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Inserm, Physiopathologie et Génétique du Neurone et du Muscle, UMR5261, U1315, Institut NeuroMyoGène, 69008, Lyon, France
| | - Salma Ellouze
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Inserm, Physiopathologie et Génétique du Neurone et du Muscle, UMR5261, U1315, Institut NeuroMyoGène, 69008, Lyon, France
- Univ Lyon, Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, 69500, Bron, France
| | - Martijn Kerkhofs
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Inserm, Physiopathologie et Génétique du Neurone et du Muscle, UMR5261, U1315, Institut NeuroMyoGène, 69008, Lyon, France
| | - Raphael Dos Reis
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Inserm, Physiopathologie et Génétique du Neurone et du Muscle, UMR5261, U1315, Institut NeuroMyoGène, 69008, Lyon, France
| | - Audrey Garcia
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Inserm, Physiopathologie et Génétique du Neurone et du Muscle, UMR5261, U1315, Institut NeuroMyoGène, 69008, Lyon, France
| | - Camille Blondet
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Inserm, Physiopathologie et Génétique du Neurone et du Muscle, UMR5261, U1315, Institut NeuroMyoGène, 69008, Lyon, France
| | - Alizée Amar
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Inserm, Physiopathologie et Génétique du Neurone et du Muscle, UMR5261, U1315, Institut NeuroMyoGène, 69008, Lyon, France
| | - Anita Kneppers
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Inserm, Physiopathologie et Génétique du Neurone et du Muscle, UMR5261, U1315, Institut NeuroMyoGène, 69008, Lyon, France
| | - Hélène Polvèche
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allée d'Italie F-69364, Lyon, France
- CECS/AFM, I-STEM, 28 rue Henri Desbruères, F-91100, Corbeil-Essonnes, France
| | - Damien Plassard
- CNRS UMR 7104, INSERM U1258, GenomEast Platform, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, Illkirch, France
| | - Marc Foretz
- Université Paris Cité, CNRS, Inserm, Institut Cochin, Paris, France
| | - Benoit Viollet
- Université Paris Cité, CNRS, Inserm, Institut Cochin, Paris, France
| | - Kei Sakamoto
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, 2200, Denmark
| | - Rémi Mounier
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Inserm, Physiopathologie et Génétique du Neurone et du Muscle, UMR5261, U1315, Institut NeuroMyoGène, 69008, Lyon, France
| | - Cyril F Bourgeois
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allée d'Italie F-69364, Lyon, France
| | - Olivier Raineteau
- Univ Lyon, Université Claude Bernard Lyon 1, Inserm, Stem Cell and Brain Research Institute U1208, 69500, Bron, France
| | - Evelyne Goillot
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Inserm, Physiopathologie et Génétique du Neurone et du Muscle, UMR5261, U1315, Institut NeuroMyoGène, 69008, Lyon, France
| | - Julien Courchet
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Inserm, Physiopathologie et Génétique du Neurone et du Muscle, UMR5261, U1315, Institut NeuroMyoGène, 69008, Lyon, France.
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11
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Tiwari A, Myeong J, Hashemiaghdam A, Zhang H, Niu X, Laramie MA, Stunault MI, Sponagel J, Patti G, Shriver L, Klyachko V, Ashrafi G. Mitochondrial pyruvate transport regulates presynaptic metabolism and neurotransmission. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.20.586011. [PMID: 38562794 PMCID: PMC10983914 DOI: 10.1101/2024.03.20.586011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Glucose has long been considered the primary fuel source for the brain. However, glucose levels fluctuate in the brain during sleep, intense circuit activity, or dietary restrictions, posing significant metabolic stress. Here, we demonstrate that the mammalian brain utilizes pyruvate as a fuel source, and pyruvate can support neuronal viability in the absence of glucose. Nerve terminals are sites of metabolic vulnerability within a neuron and we show that mitochondrial pyruvate uptake is a critical step in oxidative ATP production in hippocampal terminals. We find that the mitochondrial pyruvate carrier is post-translationally modified by lysine acetylation which in turn modulates mitochondrial pyruvate uptake. Importantly, our data reveal that the mitochondrial pyruvate carrier regulates distinct steps in synaptic transmission, namely, the spatiotemporal pattern of synaptic vesicle release and the efficiency of vesicle retrieval, functions that have profound implications for synaptic plasticity. In summary, we identify pyruvate as a potent neuronal fuel and mitochondrial pyruvate uptake as a critical node for the metabolic control of synaptic transmission in hippocampal terminals.
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Affiliation(s)
- Anupama Tiwari
- Department of Cell Biology and Physiology, Washington University in St. Louis
| | - Jongyun Myeong
- Department of Cell Biology and Physiology, Washington University in St. Louis
| | - Arsalan Hashemiaghdam
- Department of Cell Biology and Physiology, Washington University in St. Louis
- Present address: Tufts Medical Center, Boston, MA
| | - Hao Zhang
- Department of Chemistry, Department of Medicine, Center for Metabolomics and Isotope Tracing, Washington University in St. Louis
| | - Xianfeng Niu
- Department of Chemistry, Department of Medicine, Center for Metabolomics and Isotope Tracing, Washington University in St. Louis
| | - Marissa A Laramie
- Department of Cell Biology and Physiology, Washington University in St. Louis
| | - Marion I Stunault
- Department of Cell Biology and Physiology, Washington University in St. Louis
| | - Jasmin Sponagel
- Department of Cell Biology and Physiology, Washington University in St. Louis
| | - Gary Patti
- Department of Chemistry, Department of Medicine, Center for Metabolomics and Isotope Tracing, Washington University in St. Louis
| | - Leah Shriver
- Department of Chemistry, Department of Medicine, Center for Metabolomics and Isotope Tracing, Washington University in St. Louis
| | - Vitaly Klyachko
- Department of Cell Biology and Physiology, Washington University in St. Louis
| | - Ghazaleh Ashrafi
- Department of Cell Biology and Physiology, Washington University in St. Louis
- Needleman Center for Neurometabolism and Axonal Therapeutics, Washington University in St. Louis
- Lead Contact
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12
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Rademacher K, Nakamura K. Role of dopamine neuron activity in Parkinson's disease pathophysiology. Exp Neurol 2024; 373:114645. [PMID: 38092187 DOI: 10.1016/j.expneurol.2023.114645] [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: 07/30/2023] [Revised: 11/17/2023] [Accepted: 12/03/2023] [Indexed: 12/24/2023]
Abstract
Neural activity is finely tuned to produce normal behaviors, and disruptions in activity likely occur early in the course of many neurodegenerative diseases. However, how neural activity is altered, and how these changes influence neurodegeneration is poorly understood. Here, we focus on evidence that the activity of dopamine neurons is altered in Parkinson's disease (PD), either as a compensatory response to degeneration or as a result of circuit dynamics or pathologic proteins, based on available human data and studies in animal models of PD. We then discuss how this abnormal activity may augment other neurotoxic phenomena in PD, including mitochondrial deficits, protein aggregation and spread, dopamine toxicity, and excitotoxicity. A more complete picture of how activity is altered and the resulting effects on dopaminergic neuron health and function may inform future therapeutic interventions to target and protect dopamine neurons from degeneration.
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Affiliation(s)
- Katerina Rademacher
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, California, 94158, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, 20815, USA.; Graduate Program in Neuroscience, University of California San Francisco, San Francisco, California, 94158, USA
| | - Ken Nakamura
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, California, 94158, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, 20815, USA.; Graduate Program in Neuroscience, University of California San Francisco, San Francisco, California, 94158, USA; Graduate Program in Biomedical Sciences, University of California San Francisco, San Francisco, California, 94143, USA; Department of Neurology, University of California, San Francisco, San Francisco, California, 94158, USA.
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13
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Delgado MG, Delgado R. Transient Synaptic Enhancement Triggered by Exogenously Supplied Monocarboxylate in Drosophila Motoneuron Synapse. Neuroscience 2024; 539:66-75. [PMID: 38220128 DOI: 10.1016/j.neuroscience.2024.01.003] [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: 05/26/2023] [Revised: 01/05/2024] [Accepted: 01/09/2024] [Indexed: 01/16/2024]
Abstract
Current evidence suggests that glial cells provide C3 carbon sources to fuel neuronal activity; however, this notion has become challenged by biosensor studies carried out in acute brain slices or in vivo, showing that neuronal activity does not rely on the import of astrocyte-produced L-lactate. Rather, stimulated neurons become net lactate exporters, as it was also shown in Drosophila neurons, in which astrocyte-provided lactate returns as lipid droplets to be stored in glial cells. In this view, we investigate whether exogenously supplied monocarboxylates can support Drosophila motoneuron neurotransmitter release (NTR). By assessing the excitatory post-synaptic current (EPSC) amplitude under voltage-clamp as NTR indicative, we found that both pyruvate and L-lactate, as the only carbon sources in the synapses bathing-solution, cause a large transient NTR enhancement, which declines to reach a synaptic depression state, from which the synapses do not recover. The FM1-43 pre-synaptic loading ability, however, is maintained under monocarboxylate, suggesting that SV cycling should not contribute to the synaptic depression state. The NTR recovery was reached by supplementing the monocarboxylate medium with sucrose. However, monocarboxylate addition to sucrose medium does not enhance NTR, but it does when the disaccharide concentration becomes too reduced. Thus, when pyruvate concentrations become too reduced, exogenously supplied L-lactate could be converted to pyruvate and metabolized by the neural mitochondria, triggering the NTR enhancement. SIGNIFICANCE STATEMENT: The question of whether monocarboxylic acids can fuel the Drosophila motoneuron NTR was challenged. Our findings show that exogenously supplied monocarboxylates trigger a large transient synaptic enhancement just under extreme glycolysis reduction but fail to maintain NTR under sustained synaptic demand, still at low frequency stimulation, driven to the synapses to a synaptic depression state. Glycolysis activation, by adding sucrose to the monocarboxylate bath solution, restores the motoneuron NTR ability, giving place to a hexoses role in SV recruitment. Moreover these results suggest exogenously supplied C3 carbon sources could have an additional role beyond providing energetic support for neural activity.
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Affiliation(s)
- María-Graciela Delgado
- Department of Biology, Faculty of Sciences, University of Chile, Las Palmeras 3425, 7800001 Santiago, Chile.
| | - Ricardo Delgado
- Department of Biology, Faculty of Sciences, University of Chile, Las Palmeras 3425, 7800001 Santiago, Chile.
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14
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Hirabayashi Y, Lewis TL, Du Y, Virga DM, Decker AM, Coceano G, Alvelid J, Paul MA, Hamilton S, Kneis P, Takahashi Y, Gaublomme JT, Testa I, Polleux F. Most axonal mitochondria in cortical pyramidal neurons lack mitochondrial DNA and consume ATP. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.12.579972. [PMID: 38405915 PMCID: PMC10888904 DOI: 10.1101/2024.02.12.579972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
In neurons of the mammalian central nervous system (CNS), axonal mitochondria are thought to be indispensable for supplying ATP during energy-consuming processes such as neurotransmitter release. Here, we demonstrate using multiple, independent, in vitro and in vivo approaches that the majority (~80-90%) of axonal mitochondria in cortical pyramidal neurons (CPNs), lack mitochondrial DNA (mtDNA). Using dynamic, optical imaging analysis of genetically encoded sensors for mitochondrial matrix ATP and pH, we demonstrate that in axons of CPNs, but not in their dendrites, mitochondrial complex V (ATP synthase) functions in a reverse way, consuming ATP and protruding H+ out of the matrix to maintain mitochondrial membrane potential. Our results demonstrate that in mammalian CPNs, axonal mitochondria do not play a major role in ATP supply, despite playing other functions critical to regulating neurotransmission such as Ca2+ buffering.
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Affiliation(s)
- Yusuke Hirabayashi
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo; Tokyo, 113-8656, Japan
| | - Tommy L. Lewis
- Aging & Metabolism Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Yudan Du
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo; Tokyo, 113-8656, Japan
| | - Daniel M. Virga
- Department of Biological Sciences, Columbia University; New York, NY, 10027, USA
- Department of Neuroscience, Columbia University; New York, NY, 10027, USA
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, USA
| | - Aubrianna M. Decker
- Department of Biological Sciences, Columbia University; New York, NY, 10027, USA
| | - Giovanna Coceano
- Department of Applied Physics and SciLifeLab, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Jonatan Alvelid
- Department of Applied Physics and SciLifeLab, KTH Royal Institute of Technology, Stockholm, Sweden
- Department of Biophysical Imaging, Leibniz Institute of Photonic Technology, Jena, Germany
| | - Maëla A. Paul
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, USA
- Center for Interdisciplinary Research in Biology (CIRB), College de France, CNRS, INSERM, Université PSL; Paris, France
| | - Stevie Hamilton
- Department of Neuroscience, Columbia University; New York, NY, 10027, USA
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, USA
| | - Parker Kneis
- Aging & Metabolism Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Yasufumi Takahashi
- Department of Electronics, Graduate School of Engineering, Nagoya University, 464-8603, Nagoya, Japan
- Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa, 920–1192 Japan
| | - Jellert T. Gaublomme
- Department of Biological Sciences, Columbia University; New York, NY, 10027, USA
| | - Ilaria Testa
- Department of Applied Physics and SciLifeLab, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Franck Polleux
- Department of Neuroscience, Columbia University; New York, NY, 10027, USA
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, USA
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15
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Bapat O, Purimetla T, Kruessel S, Shah M, Fan R, Thum C, Rupprecht F, Langer JD, Rangaraju V. VAP spatially stabilizes dendritic mitochondria to locally support synaptic plasticity. Nat Commun 2024; 15:205. [PMID: 38177103 PMCID: PMC10766606 DOI: 10.1038/s41467-023-44233-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 12/05/2023] [Indexed: 01/06/2024] Open
Abstract
Synapses are pivotal sites of plasticity and memory formation. Consequently, synapses are energy consumption hotspots susceptible to dysfunction when their energy supplies are perturbed. Mitochondria are stabilized near synapses via the cytoskeleton and provide the local energy required for synaptic plasticity. However, the mechanisms that tether and stabilize mitochondria to support synaptic plasticity are unknown. We identified proteins exclusively tethering mitochondria to actin near postsynaptic spines. We find that VAP, the vesicle-associated membrane protein-associated protein implicated in amyotrophic lateral sclerosis, stabilizes mitochondria via actin near the spines. To test if the VAP-dependent stable mitochondrial compartments can locally support synaptic plasticity, we used two-photon glutamate uncaging for spine plasticity induction and investigated the induced and adjacent uninduced spines. We find VAP functions as a spatial stabilizer of mitochondrial compartments for up to ~60 min and as a spatial ruler determining the ~30 μm dendritic segment supported during synaptic plasticity.
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Affiliation(s)
- Ojasee Bapat
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, 33458, USA
- International Max Planck Research School for Synapses and Circuits, Jupiter, FL, 33458, USA
| | - Tejas Purimetla
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, 33458, USA
- Geisel School of Medicine at Dartmouth, Hanover, NH, 03755-1404, USA
| | - Sarah Kruessel
- Max Planck Institute for Brain Research, Frankfurt, 60438, Germany
- Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Monil Shah
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, 33458, USA
- International Max Planck Research School for Synapses and Circuits, Jupiter, FL, 33458, USA
| | - Ruolin Fan
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, 33458, USA
| | - Christina Thum
- Max Planck Institute for Brain Research, Frankfurt, 60438, Germany
| | - Fiona Rupprecht
- Max Planck Institute for Brain Research, Frankfurt, 60438, Germany
- Max Planck Institute of Biophysics, Frankfurt, 60438, Germany
- Thermo Fisher Diagnostics GmbH, Henningsdorf, 16761, Germany
| | - Julian D Langer
- Max Planck Institute for Brain Research, Frankfurt, 60438, Germany
- Max Planck Institute of Biophysics, Frankfurt, 60438, Germany
| | - Vidhya Rangaraju
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, 33458, USA.
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16
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Tiwari A, Hashemiaghdam A, Laramie MA, Maschi D, Haddad T, Stunault MI, Bergom C, Javaheri A, Klyachko V, Ashrafi G. Sirtuin3 ensures the metabolic plasticity of neurotransmission during glucose deprivation. J Cell Biol 2024; 223:e202305048. [PMID: 37988067 PMCID: PMC10660140 DOI: 10.1083/jcb.202305048] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 09/18/2023] [Accepted: 10/31/2023] [Indexed: 11/22/2023] Open
Abstract
Neurotransmission is an energetically expensive process that underlies cognition. During intense electrical activity or dietary restrictions, the glucose level in the brain plummets, forcing neurons to utilize alternative fuels. However, the molecular mechanisms of neuronal metabolic plasticity remain poorly understood. Here, we demonstrate that glucose-deprived neurons activate the CREB and PGC1α transcriptional program, which induces expression of the mitochondrial deacetylase Sirtuin 3 (Sirt3) both in vitro and in vivo. We show that Sirt3 localizes to axonal mitochondria and stimulates mitochondrial oxidative capacity in hippocampal nerve terminals. Sirt3 plays an essential role in sustaining synaptic transmission in the absence of glucose by providing metabolic support for the retrieval of synaptic vesicles after release. These results demonstrate that the transcriptional induction of Sirt3 facilitates the metabolic plasticity of synaptic transmission.
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Affiliation(s)
- Anupama Tiwari
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Arsalan Hashemiaghdam
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Marissa A. Laramie
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Dario Maschi
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Tristaan Haddad
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Marion I. Stunault
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Carmen Bergom
- Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO, USA
- Alvin J. Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA
| | - Ali Javaheri
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
- John Cochran VA Hospital, St. Louis, MO, USA
| | - Vitaly Klyachko
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Ghazaleh Ashrafi
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA
- Needleman Center for Neurometabolism and Axonal Therapeutics, Washington University School of Medicine, St. Louis, MO, USA
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17
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Rasool A, Manzoor R, Ullah K, Afzal R, Ul-Haq A, Imran H, Kaleem I, Akhtar T, Farrukh A, Hameed S, Bashir S. Oxidative Stress and Dopaminergic Metabolism: A Major PD Pathogenic Mechanism and Basis of Potential Antioxidant Therapies. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2024; 23:852-864. [PMID: 37303175 DOI: 10.2174/1871527322666230609141519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 02/19/2023] [Accepted: 03/14/2023] [Indexed: 06/13/2023]
Abstract
Reactive oxygen species (ROS)-induced oxidative stress triggers the vicious cycle leading to the degeneration of dopaminergic neurons in the nigra pars compacta. ROS produced during the metabolism of dopamine is immediately neutralized by the endogenous antioxidant defense system (EADS) under physiological conditions. Aging decreases the vigilance of EADS and makes the dopaminergic neurons more vulnerable to oxidative stress. As a result, ROS left over by EADS oxidize the dopamine-derived catechols and produces a number of reactive dopamine quinones, which are precursors to endogenous neurotoxins. In addition, ROS causes lipid peroxidation, uncoupling of the electron transport chain, and DNA damage, which lead to mitochondrial dysfunction, lysosomal dysfunction, and synaptic dysfunction. The mutations in genes such as DNAJC6, SYNJ1, SH3GL2, LRRK2, PRKN, and VPS35 caused by ROS have been associated with synaptic dysfunction and the pathogenesis of Parkinson's disease (PD). The available drugs that are used against PD can only delay the progression of the disease, but they produce various side effects. Through their antioxidant activity, flavonoids can substantiate the EADS of dopaminergic neurons and disrupt the vicious cycle incepted by oxidative stress. In this review, we show how the oxidative metabolism of dopamine generates ROS and dopamine-quinones, which then exert unrestrained OS, causing mutations in several genes involved in the proper functioning of mitochondrion, synapse, and lysosome. Besides, we also present some examples of approved drugs used for the treatment of PD, therapies in the clinical trial phase, and an update on the flavonoids that have been tested to boost the EADS of dopaminergic neurons.
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Affiliation(s)
- Aamir Rasool
- Institute for Synthetic Biosystem, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, PR China
- Institute of Biochemistry, University of Balochistan, Quetta 87300, Pakistan
| | - Robina Manzoor
- Beijing Key Laboratory for Separation and Analysis in Biomedicine and Pharmaceuticals, School of Life Science, Beijing Institute of Technology, Beijing 100081, PR China
- Faculty of Marine Sciences, Lasbella University of Agriculture Water and Marine Sciences, Uthal 90050, Pakistan
| | - Kaleem Ullah
- Department of Microbiology, University of Balochistan, Quetta 87300, Pakistan
| | - Ramsha Afzal
- Department of Brain Science, Ajou University School of Medicine, Suwon 16499, Republic of Korea
| | - Asad Ul-Haq
- Division of Rheumatology, Department of Internal Medicine, Soonchunhyang University Seoul Hospital, Seoul, Republic of Korea
| | - Hadia Imran
- Department of Biosciences, COMSATS University Islamabad, Pakistan
| | - Imdad Kaleem
- Department of Biosciences, COMSATS University Islamabad, Pakistan
| | | | - Anum Farrukh
- Department of General Medicine, Fauji Foundation Hospital (FFH), Rawalpindi, Pakistan
| | - Sahir Hameed
- National Institute for Genomics and Advanced Biotechnology (N.I.G.A.B.) National Agriculture Research Centre Islamabad, Pakistan
| | - Shahid Bashir
- Neurosciences Center, King Fahad Specialist Hospital Dammam, P.O. Box 15215, Dammam 31444, Saudi Arabia
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18
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Xiong P, Zheng YY, Ouyang JM. Carboxylated Pocoa polysaccharides inhibited oxidative damage and inflammation of HK-2 cells induced by calcium oxalate nanoparticles. Biomed Pharmacother 2023; 169:115865. [PMID: 37972469 DOI: 10.1016/j.biopha.2023.115865] [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: 08/23/2023] [Revised: 10/30/2023] [Accepted: 11/07/2023] [Indexed: 11/19/2023] Open
Abstract
The inhibitory effects of Chinese medicine Pocoa (PCPs) with different carboxyl group (-COOH) contents on oxidative damage and inflammatory response of renal epithelial cells and the influence of -COOH content in polysaccharides were investigated. HK-2 cell damage model was established by nanocalcium oxalate crystals (nanoCOM), and then PCPs with -COOH contents of 2.56% (PCP0), 7.48% (PCP1), 12.07% (PCP2), and 17.18% (PCP3) were used to protect the cells. PCPs could inhibit the damage of nanoCOM to HK-2 cells, increase cell viability, restore cytoskeleton and morphology, and improve lysosomal integrity. PCPs can reduce the oxidative stress response of nanoCOM to cells, inhibit the opening of mPTP and cell necrotic apoptosis, reduce the level of Ca2+ ions in cells, the production of ATP and MDA, and increase SOD expression. PCPs can also reduce the cellular inflammatory response caused by oxidative damage, and reduce the expression of nitric oxide (NO), inflammatory factors TNF-α, IL-6, IL-1β and MCP-1, as well as the content of inflammasome NLRP3. After protection, PCPs can inhibit the endocytosis of nanoCOM crystals by cells. With the increase in -COOH content in PCPs, its ability to inhibit nanoCOM cell damage, reduce oxidative stress, reduce inflammatory response, and inhibit crystal endocytosis increases, that is, PCP3 with the highest -COOH content, shows the best biological activity. Inhibiting cell damage and inflammation and reducing a large amount of endocytosis of crystals by cells are beneficial to inhibit the formation of kidney stones.
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Affiliation(s)
- Peng Xiong
- Jinan University, Guangzhou 510632, China; Institute of Biomineralization and Lithiasis Research, College of Chemistry and Materials Science, Guangzhou 510632, China
| | - Yu-Yun Zheng
- Jinan University, Guangzhou 510632, China; Institute of Biomineralization and Lithiasis Research, College of Chemistry and Materials Science, Guangzhou 510632, China
| | - Jian-Ming Ouyang
- Jinan University, Guangzhou 510632, China; Institute of Biomineralization and Lithiasis Research, College of Chemistry and Materials Science, Guangzhou 510632, China.
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19
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Thomas CI, Ryan MA, Kamasawa N, Scholl B. Postsynaptic mitochondria are positioned to support functional diversity of dendritic spines. eLife 2023; 12:RP89682. [PMID: 38059805 PMCID: PMC10703439 DOI: 10.7554/elife.89682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2023] Open
Abstract
Postsynaptic mitochondria are critical for the development, plasticity, and maintenance of synaptic inputs. However, their relationship to synaptic structure and functional activity is unknown. We examined a correlative dataset from ferret visual cortex with in vivo two-photon calcium imaging of dendritic spines during visual stimulation and electron microscopy reconstructions of spine ultrastructure, investigating mitochondrial abundance near functionally and structurally characterized spines. Surprisingly, we found no correlation to structural measures of synaptic strength. Instead, we found that mitochondria are positioned near spines with orientation preferences that are dissimilar to the somatic preference. Additionally, we found that mitochondria are positioned near groups of spines with heterogeneous orientation preferences. For a subset of spines with a mitochondrion in the head or neck, synapses were larger and exhibited greater selectivity to visual stimuli than those without a mitochondrion. Our data suggest mitochondria are not necessarily positioned to support the energy needs of strong spines, but rather support the structurally and functionally diverse inputs innervating the basal dendrites of cortical neurons.
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Affiliation(s)
- Connon I Thomas
- Electron Microscopy Core Facility, Max Planck Florida Institute for Neuroscience, Max Planck WayJupiterUnited States
| | - Melissa A Ryan
- Electron Microscopy Core Facility, Max Planck Florida Institute for Neuroscience, Max Planck WayJupiterUnited States
| | - Naomi Kamasawa
- Electron Microscopy Core Facility, Max Planck Florida Institute for Neuroscience, Max Planck WayJupiterUnited States
| | - Benjamin Scholl
- Department of Neuroscience, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
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20
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Myeong J, Stunault MI, Klyachko VA, Ashrafi G. Metabolic Regulation of Single Synaptic Vesicle Exo- and Endocytosis in Hippocampal Synapses. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.08.566236. [PMID: 37986894 PMCID: PMC10659320 DOI: 10.1101/2023.11.08.566236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Glucose has long been considered a primary source of energy for synaptic function. However, it remains unclear under what conditions alternative fuels, such as lactate/pyruvate, contribute to powering synaptic transmission. By detecting individual release events in cultured hippocampal synapses, we found that mitochondrial ATP production from oxidation of lactate/pyruvate regulates basal vesicle release probability and release location within the active zone (AZ) evoked by single action potentials (APs). Mitochondrial inhibition shifted vesicle release closer to the AZ center, suggesting that the energetic barrier for vesicle release is lower in the AZ center that the periphery. Mitochondrial inhibition also altered the efficiency of single AP evoked vesicle retrieval by increasing occurrence of ultrafast endocytosis, while inhibition of glycolysis had no effect. Mitochondria are sparsely distributed along hippocampal axons and we found that nerve terminals containing mitochondria displayed enhanced vesicle release and reuptake during high-frequency trains, irrespective of whether neurons were supplied with glucose or lactate. Thus, synaptic terminals can entirely bypass glycolysis to robustly maintain the vesicle cycle using oxidative fuels in the absence of glucose. These observations further suggest that mitochondrial metabolic function not only regulates several fundamental features of synaptic transmission but may also contribute to modulation of short-term synaptic plasticity.
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Affiliation(s)
- Jongyun Myeong
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, 63132, United States
| | - Marion I Stunault
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, 63132, United States
| | - Vitaly A Klyachko
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, 63132, United States
| | - Ghazaleh Ashrafi
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, 63132, United States
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, 63132, United States
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21
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Morton KS, Hartman JH, Heffernan N, Ryde IT, Kenny-Ganzert IW, Meng L, Sherwood DR, Meyer JN. Chronic high-sugar diet in adulthood protects Caenorhabditis elegans from 6-OHDA-induced dopaminergic neurodegeneration. BMC Biol 2023; 21:252. [PMID: 37950228 PMCID: PMC10636816 DOI: 10.1186/s12915-023-01733-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 10/11/2023] [Indexed: 11/12/2023] Open
Abstract
BACKGROUND Diets high in saturated fat and sugar, termed "Western diets," have been associated with several negative health outcomes, including increased risk for neurodegenerative disease. Parkinson's disease (PD) is the second most prevalent neurodegenerative disease and is characterized by the progressive death of dopaminergic neurons in the brain. We build upon previous work characterizing the impact of high-sugar diets in Caenorhabditis elegans to mechanistically evaluate the relationship between high-sugar diets and dopaminergic neurodegeneration. RESULTS Adult high-glucose and high-fructose diets, or exposure from day 1 to 5 of adulthood, led to increased lipid content, shorter lifespan, and decreased reproduction. However, in contrast to previous reports, we found that adult chronic high-glucose and high-fructose diets did not induce dopaminergic neurodegeneration alone and were protective from 6-hydroxydopamine (6-OHDA) induced degeneration. Neither sugar altered baseline electron transport chain function and both increased vulnerability to organism-wide ATP depletion when the electron transport chain was inhibited, arguing against energetic rescue as a basis for neuroprotection. The induction of oxidative stress by 6-OHDA is hypothesized to contribute to its pathology, and high-sugar diets prevented this increase in the soma of the dopaminergic neurons. However, we did not find increased expression of antioxidant enzymes or glutathione levels. Instead, we found evidence suggesting downregulation of the dopamine reuptake transporter dat-1 that could result in decreased 6-OHDA uptake. CONCLUSIONS Our work uncovers a neuroprotective role for high-sugar diets, despite concomitant decreases in lifespan and reproduction. Our results support the broader finding that ATP depletion alone is insufficient to induce dopaminergic neurodegeneration, whereas increased neuronal oxidative stress may drive degeneration. Finally, our work highlights the importance of evaluating lifestyle by toxicant interactions.
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Affiliation(s)
| | - Jessica H Hartman
- Nicholas School of Environment, Duke University, Durham, USA
- Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, USA
| | | | - Ian T Ryde
- Nicholas School of Environment, Duke University, Durham, USA
| | | | - Lingfeng Meng
- Nicholas School of Environment, Duke University, Durham, USA
| | | | - Joel N Meyer
- Nicholas School of Environment, Duke University, Durham, USA.
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22
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Clemons MR, Dimico RH, Black C, Schlussler MK, Camerino MJ, Aldinger-Gibson K, Bartle A, Reynolds N, Eisenbrandt D, Rogers A, Andrianu J, Bruce B, Elliot A, Breazeal T, Griffin H, Murphy MK, Fuerst PG. The rod synapse in aging wildtype and Dscaml1 mutant mice. PLoS One 2023; 18:e0290257. [PMID: 37910517 PMCID: PMC10619811 DOI: 10.1371/journal.pone.0290257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 08/03/2023] [Indexed: 11/03/2023] Open
Abstract
The retina is an intricately organized neural tissue built on cone and rod pathways for color and night vision. Genetic mutations that disrupt the proper function of the rod circuit contribute to blinding diseases including retinitis pigmentosa and congenital stationary night blindness (CSNB). Down Syndrome cell adhesion molecule like 1 (Dscaml1) is expressed by rods, rod bipolar cells (RBCs), and sub-populations of amacrine cells, and has been linked to a middle age onset of CSNB in humans. However, how Dscaml1 contributes to this visual deficit remains unexplored. Here, we probed Dscaml1's role in the maintenance of the rod-to-RBC synapse using a loss of function mouse model. We used immunohistochemistry to investigate the anatomical formation and maintenance of the rod-to-RBC synapse in the young, adult, and aging retina. We generated 3D reconstructions, using serial electron micrographs, of rod spherules and RBCs to measure the number of invaginating neurites, RBC dendritic tip number, and RBC mitochondrial morphology. We find that while rod-to-RBC synapses form and are maintained, similar to wildtype, that there is an increase in the number of invaginating neurites in rod spherules, a reduction in RBC dendritic tips, and reduced mitochondrial volume and complexity in the Dscaml1 mutant retina compared to controls. We also observed precocious sprouting of RBC dendrites into the outer nuclear layer (ONL) of the Dscaml1 mutant retina compared to controls. These results contribute to our knowledge of Dscaml1's role in rod circuit development and maintenance and give additional insight into possible genetic therapy targets for blinding diseases and disorders like CSNB.
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Affiliation(s)
- Mellisa R. Clemons
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Ren H. Dimico
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Cailyn Black
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Megan K. Schlussler
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Michael J. Camerino
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Kirah Aldinger-Gibson
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Amaris Bartle
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Nathan Reynolds
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Dylan Eisenbrandt
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Aspen Rogers
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - John Andrianu
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Bradley Bruce
- WWAMI Medical Education Program, University of Washington School of Medicine, Moscow, Idaho, United States of America
| | - Arthur Elliot
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Tom Breazeal
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Hannah Griffin
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Molly K. Murphy
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
- Natural Sciences, North Idaho College, Coeur d’Alene, Idaho, United States of America
| | - Peter G. Fuerst
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
- WWAMI Medical Education Program, University of Washington School of Medicine, Moscow, Idaho, United States of America
- Department of Biochemistry, Wake Forest School of Medicine, Winston Salem, North Carolina, United States of America
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23
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Theriault JE, Shaffer C, Dienel GA, Sander CY, Hooker JM, Dickerson BC, Barrett LF, Quigley KS. A functional account of stimulation-based aerobic glycolysis and its role in interpreting BOLD signal intensity increases in neuroimaging experiments. Neurosci Biobehav Rev 2023; 153:105373. [PMID: 37634556 PMCID: PMC10591873 DOI: 10.1016/j.neubiorev.2023.105373] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 07/28/2023] [Accepted: 08/23/2023] [Indexed: 08/29/2023]
Abstract
In aerobic glycolysis, oxygen is abundant, and yet cells metabolize glucose without using it, decreasing their ATP per glucose yield by 15-fold. During task-based stimulation, aerobic glycolysis occurs in localized brain regions, presenting a puzzle: why produce ATP inefficiently when, all else being equal, evolution should favor the efficient use of metabolic resources? The answer is that all else is not equal. We propose that a tradeoff exists between efficient ATP production and the efficiency with which ATP is spent to transmit information. Aerobic glycolysis, despite yielding little ATP per glucose, may support neuronal signaling in thin (< 0.5 µm), information-efficient axons. We call this the efficiency tradeoff hypothesis. This tradeoff has potential implications for interpretations of task-related BOLD "activation" observed in fMRI. We hypothesize that BOLD "activation" may index local increases in aerobic glycolysis, which support signaling in thin axons carrying "bottom-up" information, or "prediction error"-i.e., the BIAPEM (BOLD increases approximate prediction error metabolism) hypothesis. Finally, we explore implications of our hypotheses for human brain evolution, social behavior, and mental disorders.
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Affiliation(s)
- Jordan E Theriault
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA.
| | - Clare Shaffer
- Northeastern University, Department of Psychology, Boston, MA, USA
| | - Gerald A Dienel
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR, USA; Department of Cell Biology and Physiology, University of New Mexico, Albuquerque, NM, USA
| | - Christin Y Sander
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Jacob M Hooker
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Bradford C Dickerson
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA; Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Lisa Feldman Barrett
- Northeastern University, Department of Psychology, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Karen S Quigley
- Northeastern University, Department of Psychology, Boston, MA, USA; VA Bedford Healthcare System, Bedford, MA, USA
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24
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Olesen MA, Quintanilla RA. Pathological Impact of Tau Proteolytical Process on Neuronal and Mitochondrial Function: a Crucial Role in Alzheimer's Disease. Mol Neurobiol 2023; 60:5691-5707. [PMID: 37332018 DOI: 10.1007/s12035-023-03434-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 06/06/2023] [Indexed: 06/20/2023]
Abstract
Tau protein plays a pivotal role in the central nervous system (CNS), participating in microtubule stability, axonal transport, and synaptic communication. Research interest has focused on studying the role of post-translational tau modifications in mitochondrial failure, oxidative damage, and synaptic impairment in Alzheimer's disease (AD). Soluble tau forms produced by its pathological cleaved induced by caspases could lead to neuronal injury contributing to oxidative damage and cognitive decline in AD. For example, the presence of tau cleaved by caspase-3 has been suggested as a relevant factor in AD and is considered a previous event before neurofibrillary tangles (NFTs) formation.Interestingly, we and others have shown that caspase-cleaved tau in N- or C- terminal sites induce mitochondrial bioenergetics defects, axonal transport impairment, neuronal injury, and cognitive decline in neuronal cells and murine models. All these abnormalities are considered relevant in the early neurodegenerative manifestations such as memory and cognitive failure reported in AD. Therefore, in this review, we will discuss for the first time the importance of truncated tau by caspases activation in the pathogenesis of AD and how its negative actions could impact neuronal function.
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Affiliation(s)
- Margrethe A Olesen
- Laboratory of Neurodegenerative Diseases, Facultad de Ciencias de La Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, El Llano Subercaseaux 2801, 5to Piso, San Miguel, 8910060, Santiago, Chile
| | - Rodrigo A Quintanilla
- Laboratory of Neurodegenerative Diseases, Facultad de Ciencias de La Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, El Llano Subercaseaux 2801, 5to Piso, San Miguel, 8910060, Santiago, Chile.
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25
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Thomas CI, Ryan MA, Kamasawa N, Scholl B. Postsynaptic mitochondria are positioned to support functional diversity of dendritic spines. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.14.549063. [PMID: 37502969 PMCID: PMC10370038 DOI: 10.1101/2023.07.14.549063] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Postsynaptic mitochondria are critical to the development, plasticity, and maintenance of synaptic inputs. However, their relationship to synaptic structure and functional activity is unknown. We examined a correlative dataset from ferret visual cortex with in vivo two-photon calcium imaging of dendritic spines during visual stimulation and electron microscopy (EM) reconstructions of spine ultrastructure, investigating mitochondrial abundance near functionally- and structurally-characterized spines. Surprisingly, we found no correlation to structural measures of synaptic strength. Instead, we found that mitochondria are positioned near spines with orientation preferences that are dissimilar to the somatic preference. Additionally, we found that mitochondria are positioned near groups of spines with heterogeneous orientation preferences. For a subset of spines with mitochondrion in the head or neck, synapses were larger and exhibited greater selectivity to visual stimuli than those without a mitochondrion. Our data suggest mitochondria are not necessarily positioned to support the energy needs of strong spines, but rather support the structurally and functionally diverse inputs innervating the basal dendrites of cortical neurons.
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Affiliation(s)
- Connon I. Thomas
- Electron Microscopy Core Facility, Max Planck Florida Institute for Neuroscience, 1 Max Planck Way, Jupiter, FL 33458, USA
| | - Melissa A. Ryan
- Electron Microscopy Core Facility, Max Planck Florida Institute for Neuroscience, 1 Max Planck Way, Jupiter, FL 33458, USA
- Present Address: Department of Neuroscience, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Naomi Kamasawa
- Electron Microscopy Core Facility, Max Planck Florida Institute for Neuroscience, 1 Max Planck Way, Jupiter, FL 33458, USA
| | - Benjamin Scholl
- Department of Neuroscience, Perelman School of Medicine at the University of Pennsylvania, 415 Curie Blvd, Philadelphia, PA, 19104, USA
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26
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Morton KS, Hartman JS, Heffernan N, Ryde I, Kenny-Ganzert IW, Meng L, Sherwood DR, Meyer JN. Chronic high-sugar diet in adulthood protects Caenorhabditis elegans from 6-OHDA induced dopaminergic neurodegeneration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.29.542737. [PMID: 37398434 PMCID: PMC10312447 DOI: 10.1101/2023.05.29.542737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
BACKGROUND Diets high in saturated fat and sugar, termed western diets, have been associated with several negative health outcomes, including increased risk for neurodegenerative disease. Parkinson s Disease (PD) is the second most prevalent neurodegenerative disease and is characterized by the progressive death of dopaminergic neurons in the brain. We build upon previous work characterizing the impact of high sugar diets in Caenorhabditis elegans to mechanistically evaluate the relationship between high sugar diets and dopaminergic neurodegeneration. RESULTS Non-developmental high glucose and fructose diets led to increased lipid content and shorter lifespan and decreased reproduction. However, in contrast to previous reports, we found that non-developmental chronic high-glucose and high-fructose diets did not induce dopaminergic neurodegeneration alone and were protective from 6-hydroxydopamine (6-OHDA) induced degeneration. Neither sugar altered baseline electron transport chain function, and both increased vulnerability to organism-wide ATP depletion when the electron transport chain was inhibited, arguing against energetic rescue as a basis for neuroprotection. The induction of oxidative stress by 6-OHDA is hypothesized to contribute to its pathology, and high sugar diets prevented this increase in the soma of the dopaminergic neurons. However, we did not find increased expression of antioxidant enzymes or glutathione levels. Instead, we found evidence suggesting alterations to dopamine transmission that could result in decreased 6-OHDA uptake. CONCLUSION Our work uncovers a neuroprotective role for high sugar diets, despite concomitant decreases in lifespan and reproduction. Our results support the broader finding that ATP depletion alone is insufficient to induce dopaminergic neurodegeneration, whereas increased neuronal oxidative stress may drive degeneration. Finally, our work highlights the importance of evaluating lifestyle by toxicant interactions.
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27
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Underwood EL, Redell JB, Hood KN, Maynard ME, Hylin M, Waxham MN, Zhao J, Moore AN, Dash PK. Enhanced presynaptic mitochondrial energy production is required for memory formation. Sci Rep 2023; 13:14431. [PMID: 37660191 PMCID: PMC10475119 DOI: 10.1038/s41598-023-40877-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 08/17/2023] [Indexed: 09/04/2023] Open
Abstract
Some of the prominent features of long-term memory formation include protein synthesis, gene expression, enhanced neurotransmitter release, increased excitability, and formation of new synapses. As these processes are critically dependent on mitochondrial function, we hypothesized that increased mitochondrial respiration and dynamics would play a prominent role in memory formation. To address this possibility, we measured mitochondrial oxygen consumption (OCR) in hippocampal tissue punches from trained and untrained animals. Our results show that context fear training significantly increased basal, ATP synthesis-linked, and maximal OCR in the Shaffer collateral-CA1 synaptic region, but not in the CA1 cell body layer. These changes were recapitulated in synaptosomes isolated from the hippocampi of fear-trained animals. As dynamin-related protein 1 (Drp1) plays an important role in mitochondrial fission, we examined its role in the increased mitochondrial respiration observed after fear training. Drp1 inhibitors decreased the training-associated enhancement of OCR and impaired contextual fear memory, but did not alter the number of synaptosomes containing mitochondria. Taken together, our results show context fear training increases presynaptic mitochondria respiration, and that Drp-1 mediated enhanced energy production in CA1 pre-synaptic terminals is necessary for context fear memory that does not result from an increase in the number of synaptosomes containing mitochondria or an increase in mitochondrial mass within the synaptic layer.
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Affiliation(s)
- Erica L Underwood
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, P.O. Box 20708, Houston, TX, 77225, USA
| | - John B Redell
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, P.O. Box 20708, Houston, TX, 77225, USA.
| | - Kimberly N Hood
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, P.O. Box 20708, Houston, TX, 77225, USA
| | - Mark E Maynard
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, P.O. Box 20708, Houston, TX, 77225, USA
- Department of Electrical and Computer Engineering, University of Houston, Houston, TX, USA
| | - Michael Hylin
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, P.O. Box 20708, Houston, TX, 77225, USA
- Department of Psychology, Southern Illinois University, Carbondale, IL, USA
| | - M Neal Waxham
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, P.O. Box 20708, Houston, TX, 77225, USA
| | - Jing Zhao
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, P.O. Box 20708, Houston, TX, 77225, USA
| | - Anthony N Moore
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, P.O. Box 20708, Houston, TX, 77225, USA
| | - Pramod K Dash
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, P.O. Box 20708, Houston, TX, 77225, USA
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28
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Anantha J, Wilson FE, McCarthy E, Morales-Prieto N, Mazzocchi M, Collins LM, Sullivan AM, O'Keeffe GW. A combined proteomics and bioinformatics analysis of ZNHIT1-interacting proteins reveals a significant enrichment in proteins associated with mitochondrial function. J Chem Neuroanat 2023; 131:102288. [PMID: 37178741 DOI: 10.1016/j.jchemneu.2023.102288] [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: 12/14/2022] [Revised: 05/05/2023] [Accepted: 05/10/2023] [Indexed: 05/15/2023]
Abstract
Adenosine 5'-triphosphate (ATP) is the principal source of cellular energy, which is essential for neuronal health and maintenance. Parkinson's disease (PD) and other neurodegenerative disorders are characterised by impairments in mitochondrial function and reductions in cellular ATP levels. Thus there is a need to better understand the biology of intracellular regulators of ATP production, in order to inform the development of new neuroprotective therapies for diseases such as PD. One such regulator is Zinc finger HIT-domain containing protein 1 (ZNHIT1). ZNHIT1 is an evolutionarily-conserved component of a chromatin-remodelling complex, which has been recently shown to increase cellular ATP production in SH-SY5Y cells and to protect against impairments in mitochondrial function caused by alpha-synuclein, a protein which is integral to PD pathophysiology. This effect of ZNHIT1 on cellular ATP production is thought to be due to increased expression of genes associated with mitochondrial function, but it is also possible that ZNHIT1 regulates mitochondrial function by binding to mitochondrial proteins. To examine this question, we performed a combined proteomics and bioinformatics analysis to identify ZNHIT1-interacting proteins in SH-SY5Y cells. We report that ZNHIT1-interacting proteins are significantly enriched in multiple functional categories, including mitochondrial transport, ATP synthesis and ATP-dependent activity. Furthermore we also report that the correlation between ZNHIT1 and dopaminergic markers is reduced in the PD brain. These data suggest that the reported beneficial effects of ZNHIT1 on ATP production may be mediated, at least in part, by its direct interaction with mitochondrial proteins and suggest that potential alterations in ZNHIT1 in PD may contribute to the known impairments in ATP generation in midbrain dopaminergic neurons in PD.
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Affiliation(s)
- Jayanth Anantha
- Department of Anatomy & Neuroscience, University College Cork (UCC), Cork, Ireland
| | - Fionnuala E Wilson
- Department of Anatomy & Neuroscience, University College Cork (UCC), Cork, Ireland
| | - Erin McCarthy
- Department of Anatomy & Neuroscience, University College Cork (UCC), Cork, Ireland
| | | | - Martina Mazzocchi
- Department of Anatomy & Neuroscience, University College Cork (UCC), Cork, Ireland
| | - Louise M Collins
- Department of Anatomy & Neuroscience, University College Cork (UCC), Cork, Ireland; Parkinson's Disease Research Cluster (PDRC), University College Cork, Cork, Ireland
| | - Aideen M Sullivan
- Department of Anatomy & Neuroscience, University College Cork (UCC), Cork, Ireland; Parkinson's Disease Research Cluster (PDRC), University College Cork, Cork, Ireland; APC Microbiome Ireland, University College Cork, Cork, Ireland.
| | - Gerard W O'Keeffe
- Department of Anatomy & Neuroscience, University College Cork (UCC), Cork, Ireland; Parkinson's Disease Research Cluster (PDRC), University College Cork, Cork, Ireland; APC Microbiome Ireland, University College Cork, Cork, Ireland.
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29
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Newell AJ, Jima D, Reading B, Patisaul HB. Machine learning reveals common transcriptomic signatures across rat brain and placenta following developmental organophosphate ester exposure. Toxicol Sci 2023; 195:103-122. [PMID: 37399109 PMCID: PMC10695431 DOI: 10.1093/toxsci/kfad062] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/05/2023] Open
Abstract
Toxicogenomics is a critical area of inquiry for hazard identification and to identify both mechanisms of action and potential markers of exposure to toxic compounds. However, data generated by these experiments are highly dimensional and present challenges to standard statistical approaches, requiring strict correction for multiple comparisons. This stringency often fails to detect meaningful changes to low expression genes and/or eliminate genes with small but consistent changes particularly in tissues where slight changes in expression can have important functional differences, such as brain. Machine learning offers an alternative analytical approach for "omics" data that effectively sidesteps the challenges of analyzing highly dimensional data. Using 3 rat RNA transcriptome sets, we utilized an ensemble machine learning approach to predict developmental exposure to a mixture of organophosphate esters (OPEs) in brain (newborn cortex and day 10 hippocampus) and late gestation placenta of male and female rats, and identified genes that informed predictor performance. OPE exposure had sex specific effects on hippocampal transcriptome, and significantly impacted genes associated with mitochondrial transcriptional regulation and cation transport in females, including voltage-gated potassium and calcium channels and subunits. To establish if this holds for other tissues, RNAseq data from cortex and placenta, both previously published and analyzed via a more traditional pipeline, were reanalyzed with the ensemble machine learning methodology. Significant enrichment for pathways of oxidative phosphorylation and electron transport chain was found, suggesting a transcriptomic signature of OPE exposure impacting mitochondrial metabolism across tissue types and developmental epoch. Here we show how machine learning can complement more traditional analytical approaches to identify vulnerable "signature" pathways disrupted by chemical exposures and biomarkers of exposure.
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Affiliation(s)
- Andrew J Newell
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Dereje Jima
- Molecular Education, Technology, and Research Innovation Center, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Benjamin Reading
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Heather B Patisaul
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina 27695, USA
- Center for Human Health and the Environment, North Carolina State University, Raleigh, North Carolina 27695, USA
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30
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Michanski S, Henneck T, Mukhopadhyay M, Steyer AM, Gonzalez PA, Grewe K, Ilgen P, Gültas M, Fornasiero EF, Jakobs S, Möbius W, Vogl C, Pangršič T, Rizzoli SO, Wichmann C. Age-dependent structural reorganization of utricular ribbon synapses. Front Cell Dev Biol 2023; 11:1178992. [PMID: 37635868 PMCID: PMC10447907 DOI: 10.3389/fcell.2023.1178992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 07/17/2023] [Indexed: 08/29/2023] Open
Abstract
In mammals, spatial orientation is synaptically-encoded by sensory hair cells of the vestibular labyrinth. Vestibular hair cells (VHCs) harbor synaptic ribbons at their presynaptic active zones (AZs), which play a critical role in molecular scaffolding and facilitate synaptic release and vesicular replenishment. With advancing age, the prevalence of vestibular deficits increases; yet, the underlying mechanisms are not well understood and the possible accompanying morphological changes in the VHC synapses have not yet been systematically examined. We investigated the effects of maturation and aging on the ultrastructure of the ribbon-type AZs in murine utricles using various electron microscopic techniques and combined them with confocal and super-resolution light microscopy as well as metabolic imaging up to 1 year of age. In older animals, we detected predominantly in type I VHCs the formation of floating ribbon clusters, mostly consisting of newly synthesized ribbon material. Our findings suggest that VHC ribbon-type AZs undergo dramatic structural alterations upon aging.
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Affiliation(s)
- Susann Michanski
- Molecular Architecture of Synapses Group, Institute for Auditory Neuroscience, InnerEarLab and Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen, Germany
- Collaborative Research Center 889, University of Göttingen, Göttingen, Germany
- Multiscale Bioimaging Cluster of Excellence (MBExC), University of Göttingen, Göttingen, Germany
| | - Timo Henneck
- Biology Bachelor Program, University of Göttingen, Göttingen, Germany
| | - Mohona Mukhopadhyay
- Experimental Otology Group, InnerEarLab, Department of Otolaryngology, Institute for Auditory Neuroscience, University Medical Center Göttingen, Göttingen, Germany
| | - Anna M. Steyer
- Electron Microscopy-City Campus, Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Center Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), University of Göttingen, Göttingen, Germany
| | - Paola Agüi Gonzalez
- Department for Neuro-and Sensory Physiology, University Medical Center Göttingen, Center for Biostructural Imaging of Neurodegeneration (BIN), Göttingen, Germany
| | - Katharina Grewe
- Department for Neuro-and Sensory Physiology, University Medical Center Göttingen, Center for Biostructural Imaging of Neurodegeneration (BIN), Göttingen, Germany
| | - Peter Ilgen
- Clinic of Neurology, University Medical Center Göttingen, Göttingen, Germany
- Department of NanoBiophotonics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Translational Neuroinflammation and Automated Microscopy TNM, Göttingen, Germany
| | - Mehmet Gültas
- Faculty of Agriculture, South Westphalia University of Applied Sciences, Soest, Germany
| | - Eugenio F. Fornasiero
- Department for Neuro-and Sensory Physiology, University Medical Center Göttingen, Center for Biostructural Imaging of Neurodegeneration (BIN), Göttingen, Germany
| | - Stefan Jakobs
- Clinic of Neurology, University Medical Center Göttingen, Göttingen, Germany
- Department of NanoBiophotonics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Translational Neuroinflammation and Automated Microscopy TNM, Göttingen, Germany
| | - Wiebke Möbius
- Multiscale Bioimaging Cluster of Excellence (MBExC), University of Göttingen, Göttingen, Germany
- Electron Microscopy-City Campus, Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Christian Vogl
- Collaborative Research Center 889, University of Göttingen, Göttingen, Germany
- Presynaptogenesis and Intracellular Transport in Hair Cells Group, Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, Göttingen, Germany
- Auditory Neuroscience Group, Institute of Physiology, Medical University Innsbruck, Innsbruck, Austria
| | - Tina Pangršič
- Collaborative Research Center 889, University of Göttingen, Göttingen, Germany
- Multiscale Bioimaging Cluster of Excellence (MBExC), University of Göttingen, Göttingen, Germany
- Experimental Otology Group, InnerEarLab, Department of Otolaryngology, Institute for Auditory Neuroscience, University Medical Center Göttingen, Göttingen, Germany
| | - Silvio O. Rizzoli
- Department for Neuro-and Sensory Physiology, University Medical Center Göttingen, Center for Biostructural Imaging of Neurodegeneration (BIN), Göttingen, Germany
| | - Carolin Wichmann
- Molecular Architecture of Synapses Group, Institute for Auditory Neuroscience, InnerEarLab and Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen, Germany
- Collaborative Research Center 889, University of Göttingen, Göttingen, Germany
- Multiscale Bioimaging Cluster of Excellence (MBExC), University of Göttingen, Göttingen, Germany
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31
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Beccano-Kelly DA, Cherubini M, Mousba Y, Cramb KM, Giussani S, Caiazza MC, Rai P, Vingill S, Bengoa-Vergniory N, Ng B, Corda G, Banerjee A, Vowles J, Cowley S, Wade-Martins R. Calcium dysregulation combined with mitochondrial failure and electrophysiological maturity converge in Parkinson's iPSC-dopamine neurons. iScience 2023; 26:107044. [PMID: 37426342 PMCID: PMC10329047 DOI: 10.1016/j.isci.2023.107044] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 11/30/2022] [Accepted: 06/01/2023] [Indexed: 07/11/2023] Open
Abstract
Parkinson's disease (PD) is characterized by a progressive deterioration of motor and cognitive functions. Although death of dopamine neurons is the hallmark pathology of PD, this is a late-stage disease process preceded by neuronal dysfunction. Here we describe early physiological perturbations in patient-derived induced pluripotent stem cell (iPSC)-dopamine neurons carrying the GBA-N370S mutation, a strong genetic risk factor for PD. GBA-N370S iPSC-dopamine neurons show an early and persistent calcium dysregulation notably at the mitochondria, followed by reduced mitochondrial membrane potential and oxygen consumption rate, indicating mitochondrial failure. With increased neuronal maturity, we observed decreased synaptic function in PD iPSC-dopamine neurons, consistent with the requirement for ATP and calcium to support the increase in electrophysiological activity over time. Our work demonstrates that calcium dyshomeostasis and mitochondrial failure impair the higher electrophysiological activity of mature neurons and may underlie the vulnerability of dopamine neurons in PD.
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Affiliation(s)
- Dayne A. Beccano-Kelly
- Oxford Parkinson’s Disease Centre, University of Oxford, Oxford, United Kingdom
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX3 7BN, UK
| | - Marta Cherubini
- Oxford Parkinson’s Disease Centre, University of Oxford, Oxford, United Kingdom
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX3 7BN, UK
| | - Yassine Mousba
- Oxford Parkinson’s Disease Centre, University of Oxford, Oxford, United Kingdom
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX3 7BN, UK
| | - Kaitlyn M.L. Cramb
- Oxford Parkinson’s Disease Centre, University of Oxford, Oxford, United Kingdom
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX3 7BN, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford OX1 3QU, UK
| | - Stefania Giussani
- Oxford Parkinson’s Disease Centre, University of Oxford, Oxford, United Kingdom
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX3 7BN, UK
| | - Maria Claudia Caiazza
- Oxford Parkinson’s Disease Centre, University of Oxford, Oxford, United Kingdom
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX3 7BN, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford OX1 3QU, UK
| | - Pavandeep Rai
- Oxford Parkinson’s Disease Centre, University of Oxford, Oxford, United Kingdom
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX3 7BN, UK
| | - Siv Vingill
- Oxford Parkinson’s Disease Centre, University of Oxford, Oxford, United Kingdom
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX3 7BN, UK
| | - Nora Bengoa-Vergniory
- Oxford Parkinson’s Disease Centre, University of Oxford, Oxford, United Kingdom
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX3 7BN, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford OX1 3QU, UK
| | - Bryan Ng
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX3 7BN, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford OX1 3QU, UK
| | - Gabriele Corda
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX3 7BN, UK
| | - Abhirup Banerjee
- Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, Oxford OX3 9DU, UK
- Department of Engineering Science, Institute of Biomedical Engineering, University of Oxford, Oxford OX3 7DQ, UK
| | - Jane Vowles
- Oxford Parkinson’s Disease Centre, University of Oxford, Oxford, United Kingdom
- The James Martin Stem Cell Facility, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Sally Cowley
- Oxford Parkinson’s Disease Centre, University of Oxford, Oxford, United Kingdom
- The James Martin Stem Cell Facility, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Richard Wade-Martins
- Oxford Parkinson’s Disease Centre, University of Oxford, Oxford, United Kingdom
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX3 7BN, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford OX1 3QU, UK
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32
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Yang S, Park JH, Lu HC. Axonal energy metabolism, and the effects in aging and neurodegenerative diseases. Mol Neurodegener 2023; 18:49. [PMID: 37475056 PMCID: PMC10357692 DOI: 10.1186/s13024-023-00634-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 06/08/2023] [Indexed: 07/22/2023] Open
Abstract
Human studies consistently identify bioenergetic maladaptations in brains upon aging and neurodegenerative disorders of aging (NDAs), such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and Amyotrophic lateral sclerosis. Glucose is the major brain fuel and glucose hypometabolism has been observed in brain regions vulnerable to aging and NDAs. Many neurodegenerative susceptible regions are in the topological central hub of the brain connectome, linked by densely interconnected long-range axons. Axons, key components of the connectome, have high metabolic needs to support neurotransmission and other essential activities. Long-range axons are particularly vulnerable to injury, neurotoxin exposure, protein stress, lysosomal dysfunction, etc. Axonopathy is often an early sign of neurodegeneration. Recent studies ascribe axonal maintenance failures to local bioenergetic dysregulation. With this review, we aim to stimulate research in exploring metabolically oriented neuroprotection strategies to enhance or normalize bioenergetics in NDA models. Here we start by summarizing evidence from human patients and animal models to reveal the correlation between glucose hypometabolism and connectomic disintegration upon aging/NDAs. To encourage mechanistic investigations on how axonal bioenergetic dysregulation occurs during aging/NDAs, we first review the current literature on axonal bioenergetics in distinct axonal subdomains: axon initial segments, myelinated axonal segments, and axonal arbors harboring pre-synaptic boutons. In each subdomain, we focus on the organization, activity-dependent regulation of the bioenergetic system, and external glial support. Second, we review the mechanisms regulating axonal nicotinamide adenine dinucleotide (NAD+) homeostasis, an essential molecule for energy metabolism processes, including NAD+ biosynthetic, recycling, and consuming pathways. Third, we highlight the innate metabolic vulnerability of the brain connectome and discuss its perturbation during aging and NDAs. As axonal bioenergetic deficits are developing into NDAs, especially in asymptomatic phase, they are likely exaggerated further by impaired NAD+ homeostasis, the high energetic cost of neural network hyperactivity, and glial pathology. Future research in interrogating the causal relationship between metabolic vulnerability, axonopathy, amyloid/tau pathology, and cognitive decline will provide fundamental knowledge for developing therapeutic interventions.
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Affiliation(s)
- Sen Yang
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA
| | - Jung Hyun Park
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA
| | - Hui-Chen Lu
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA.
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA.
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA.
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33
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Stauch KL, Totusek S, Trease AJ, Estrella LD, Emanuel K, Fangmeier A, Fox HS. Longitudinal in vivo metabolic labeling reveals tissue-specific mitochondrial proteome turnover rates and proteins selectively altered by parkin deficiency. Sci Rep 2023; 13:11414. [PMID: 37452120 PMCID: PMC10349111 DOI: 10.1038/s41598-023-38484-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 07/09/2023] [Indexed: 07/18/2023] Open
Abstract
Our study utilizes a longitudinal isotopic metabolic labeling approach in vivo in combination with organelle fraction proteomics to address the role of parkin in mitochondrial protein turnover in mice. The use of metabolic labeling provides a method to quantitatively determine the global changes in protein half-lives whilst simultaneously assessing protein expression. Studying two diverse mitochondrial populations, we demonstrated the median half-life of brain striatal synaptic mitochondrial proteins is significantly greater than that of hepatic mitochondrial proteins (25.7 vs. 3.5 days). Furthermore, loss of parkin resulted in an overall, albeit modest, increase in both mitochondrial protein abundance and half-life. Pathway and functional analysis of our proteomics data identified both known and novel pathways affected by loss of parkin that are consistent with its role in both mitochondrial quality control and neurodegeneration. Our study therefore adds to a growing body of evidence suggesting dependence on parkin is low for basal mitophagy in vivo and provides a foundation for the investigation of novel parkin targets.
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Affiliation(s)
- K L Stauch
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE, USA
| | - S Totusek
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE, USA
| | - A J Trease
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE, USA
| | - L D Estrella
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE, USA
| | - K Emanuel
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE, USA
| | - A Fangmeier
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE, USA
| | - H S Fox
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE, USA.
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34
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Kuznetsov IA, Kuznetsov AV. Mitochondrial transport in symmetric and asymmetric axons with multiple branching junctions: a computational study. Comput Methods Biomech Biomed Engin 2023:1-20. [PMID: 37424316 PMCID: PMC10776827 DOI: 10.1080/10255842.2023.2226787] [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: 04/03/2023] [Revised: 05/10/2023] [Accepted: 06/10/2023] [Indexed: 07/11/2023]
Abstract
Mitochondrial aging has been proposed to be involved in a variety of neurodegenerative disorders, such as Parkinson's disease. Here, we explore the impact of multiple branching junctions in axons on the mean age of mitochondria and their age density distributions in demand sites. The study examined mitochondrial concentration, mean age, and age density distribution in relation to the distance from the soma. We developed models for a symmetric axon containing 14 demand sites and an asymmetric axon containing 10 demand sites. We investigated how the concentration of mitochondria changes when an axon splits into two branches at the branching junction. Additionally, we studied whether mitochondrial concentrations in the branches are affected by what proportion of mitochondrial flux enters the upper branch versus the lower branch. Furthermore, we explored whether the distributions of mitochondrial mean age and age density in branching axons are affected by how the mitochondrial flux splits at the branching junction. When the mitochondrial flux is unevenly split at the branching junction of an asymmetric axon, with a greater proportion of the flux entering the longer branch, the average age of mitochondria (system age) in the axon increases. Our findings elucidate the effects of axonal branching on the mitochondrial age.
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Affiliation(s)
- Ivan A Kuznetsov
- Perelman School of Medicine, University of PA, Philadelphia, PA, USA
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Andrey V Kuznetsov
- Department of Mechanical and Aerospace Engineering, NC State University, Raleigh, NC, USA
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35
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Fernández de la Torre M, Fiuza-Luces C, Laine-Menéndez S, Delmiro A, Arenas J, Martín MÁ, Lucia A, Morán M. Pathophysiology of Cerebellar Degeneration in Mitochondrial Disorders: Insights from the Harlequin Mouse. Int J Mol Sci 2023; 24:10973. [PMID: 37446148 DOI: 10.3390/ijms241310973] [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: 05/21/2023] [Revised: 06/22/2023] [Accepted: 06/28/2023] [Indexed: 07/15/2023] Open
Abstract
By means of a proteomic approach, we assessed the pathways involved in cerebellar neurodegeneration in a mouse model (Harlequin, Hq) of mitochondrial disorder. A differential proteomic profile study (iTRAQ) was performed in cerebellum homogenates of male Hq and wild-type (WT) mice 8 weeks after the onset of clear symptoms of ataxia in the Hq mice (aged 5.2 ± 0.2 and 5.3 ± 0.1 months for WT and Hq, respectively), followed by a biochemical validation of the most relevant changes. Additional groups of 2-, 3- and 6-month-old WT and Hq mice were analyzed to assess the disease progression on the proteins altered in the proteomic study. The proteomic analysis showed that beyond the expected deregulation of oxidative phosphorylation, the cerebellum of Hq mice showed a marked astroglial activation together with alterations in Ca2+ homeostasis and neurotransmission, with an up- and downregulation of GABAergic and glutamatergic neurotransmission, respectively, and the downregulation of cerebellar "long-term depression", a synaptic plasticity phenomenon that is a major player in the error-driven learning that occurs in the cerebellar cortex. Our study provides novel insights into the mechanisms associated with cerebellar degeneration in the Hq mouse model, including a complex deregulation of neuroinflammation, oxidative phosphorylation and glutamate, GABA and amino acids' metabolism.
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Affiliation(s)
- Miguel Fernández de la Torre
- Mitochondrial and Neuromuscular Diseases Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), 28041 Madrid, Spain
| | - Carmen Fiuza-Luces
- Mitochondrial and Neuromuscular Diseases Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), 28041 Madrid, Spain
| | - Sara Laine-Menéndez
- Mitochondrial and Neuromuscular Diseases Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), 28041 Madrid, Spain
| | - Aitor Delmiro
- Mitochondrial and Neuromuscular Diseases Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), 28041 Madrid, Spain
- Spanish Network for Biomedical Research in Rare Diseases (CIBERER), U723, 28029 Madrid, Spain
- Servicio de Bioquímica Clínica, Hospital Universitario "12 de Octubre", 28041 Madrid, Spain
| | - Joaquín Arenas
- Mitochondrial and Neuromuscular Diseases Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), 28041 Madrid, Spain
- Spanish Network for Biomedical Research in Rare Diseases (CIBERER), U723, 28029 Madrid, Spain
| | - Miguel Ángel Martín
- Mitochondrial and Neuromuscular Diseases Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), 28041 Madrid, Spain
- Spanish Network for Biomedical Research in Rare Diseases (CIBERER), U723, 28029 Madrid, Spain
- Servicio de Genética, Hospital Universitario "12 de Octubre", 28041 Madrid, Spain
| | - Alejandro Lucia
- Faculty of Sports Sciences, European University of Madrid, 28670 Madrid, Spain
- Spanish Network for Biomedical Research in Fragility and Healthy Aging (CIBERFES), 28029 Madrid, Spain
| | - María Morán
- Mitochondrial and Neuromuscular Diseases Laboratory, Instituto de Investigación Sanitaria Hospital '12 de Octubre' ('imas12'), 28041 Madrid, Spain
- Spanish Network for Biomedical Research in Rare Diseases (CIBERER), U723, 28029 Madrid, Spain
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36
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Barros LF, Ruminot I, Sandoval PY, San Martín A. Enlightening brain energy metabolism. Neurobiol Dis 2023:106211. [PMID: 37352985 DOI: 10.1016/j.nbd.2023.106211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 05/06/2023] [Accepted: 06/20/2023] [Indexed: 06/25/2023] Open
Abstract
Brain tissue metabolism is distributed across several cell types and subcellular compartments, which activate at different times and with different temporal patterns. The introduction of genetically-encoded fluorescent indicators that are imaged using time-lapse microscopy has opened the possibility of studying brain metabolism at cellular and sub-cellular levels. There are indicators for sugars, monocarboxylates, Krebs cycle intermediates, amino acids, cofactors, and energy nucleotides, which inform about relative levels, concentrations and fluxes. This review offers a brief survey of the metabolic indicators that have been validated in brain cells, with some illustrative examples from the literature. Whereas only a small fraction of the metabolome is currently accessible to fluorescent probes, there are grounds to be optimistic about coming developments and the application of these tools to the study of brain disease.
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Affiliation(s)
- L F Barros
- Centro de Estudios Científicos (CECs), Valdivia, Chile; Facultad de Medicina y Ciencia, Universidad San Sebastián, Valdivia, Chile.
| | - I Ruminot
- Centro de Estudios Científicos (CECs), Valdivia, Chile; Facultad de Ciencias para el Cuidado de La Salud, Universidad San Sebastián, Valdivia, Chile
| | - P Y Sandoval
- Centro de Estudios Científicos (CECs), Valdivia, Chile; Facultad de Ciencias para el Cuidado de La Salud, Universidad San Sebastián, Valdivia, Chile
| | - A San Martín
- Centro de Estudios Científicos (CECs), Valdivia, Chile; Facultad de Ciencias para el Cuidado de La Salud, Universidad San Sebastián, Valdivia, Chile
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37
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Gorski K, Jackson CB, Nyman TA, Rezov V, Battersby BJ, Lehesjoki AE. Progressive mitochondrial dysfunction in cerebellar synaptosomes of cystatin B-deficient mice. Front Mol Neurosci 2023; 16:1175851. [PMID: 37251643 PMCID: PMC10213208 DOI: 10.3389/fnmol.2023.1175851] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 04/25/2023] [Indexed: 05/31/2023] Open
Abstract
The involvement of mitochondrial dysfunction in cystatin B (CSTB) deficiency has been suggested, but its role in the onset of neurodegeneration, myoclonus, and ataxia in the CSTB-deficient mouse model (Cstb-/-) is yet unknown. CSTB is an inhibitor of lysosomal and nuclear cysteine cathepsins. In humans, partial loss-of-function mutations cause the progressive myoclonus epilepsy neurodegenerative disorder, EPM1. Here we applied proteome analysis and respirometry on cerebellar synaptosomes from early symptomatic (Cstb-/-) mice to identify the molecular mechanisms involved in the onset of CSTB-deficiency associated neural pathogenesis. Proteome analysis showed that CSTB deficiency is associated with differential expression of mitochondrial and synaptic proteins, and respirometry revealed a progressive impairment in mitochondrial function coinciding with the onset of myoclonus and neurodegeneration in (Cstb-/-) mice. This mitochondrial dysfunction was not associated with alterations in mitochondrial DNA copy number or membrane ultrastructure. Collectively, our results show that CSTB deficiency generates a defect in synaptic mitochondrial bioenergetics that coincides with the onset and progression of the clinical phenotypes, and thus is likely a contributor to the pathogenesis of EPM1.
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Affiliation(s)
- Katarin Gorski
- Folkhälsan Research Center, Helsinki, Finland
- Medicum, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Christopher B. Jackson
- Department of Biochemistry and Developmental Biology, Medicum, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Tuula A. Nyman
- Department of Immunology, Oslo University Hospital, University of Oslo, Oslo, Norway
| | - Veronika Rezov
- Folkhälsan Research Center, Helsinki, Finland
- Medicum, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | | | - Anna-Elina Lehesjoki
- Folkhälsan Research Center, Helsinki, Finland
- Medicum, Faculty of Medicine, University of Helsinki, Helsinki, Finland
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38
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O'Connor K, Spendiff S, Lochmüller H, Horvath R. Mitochondrial Mutations Can Alter Neuromuscular Transmission in Congenital Myasthenic Syndrome and Mitochondrial Disease. Int J Mol Sci 2023; 24:ijms24108505. [PMID: 37239850 DOI: 10.3390/ijms24108505] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 04/28/2023] [Accepted: 05/02/2023] [Indexed: 05/28/2023] Open
Abstract
Congenital myasthenic syndromes (CMS) are a group of rare, neuromuscular disorders that usually present in childhood or infancy. While the phenotypic presentation of these disorders is diverse, the unifying feature is a pathomechanism that disrupts neuromuscular transmission. Recently, two mitochondrial genes-SLC25A1 and TEFM-have been reported in patients with suspected CMS, prompting a discussion about the role of mitochondria at the neuromuscular junction (NMJ). Mitochondrial disease and CMS can present with similar symptoms, and potentially one in four patients with mitochondrial myopathy exhibit NMJ defects. This review highlights research indicating the prominent roles of mitochondria at both the pre- and postsynapse, demonstrating the potential for mitochondrial involvement in neuromuscular transmission defects. We propose the establishment of a novel subcategorization for CMS-mitochondrial CMS, due to unifying clinical features and the potential for mitochondrial defects to impede transmission at the pre- and postsynapse. Finally, we highlight the potential of targeting the neuromuscular transmission in mitochondrial disease to improve patient outcomes.
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Affiliation(s)
- Kaela O'Connor
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON K1H 8L1, Canada
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
- Centre for Neuromuscular Disease, University of Ottawa Brain and Mind Research Institute, Ottawa, ON K1H 8M5, Canada
| | - Sally Spendiff
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON K1H 8L1, Canada
| | - Hanns Lochmüller
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON K1H 8L1, Canada
- Division of Neurology, Department of Medicine, The Ottawa Hospital, Ottawa, ON K1H 8L6, Canada
- Brain and Mind Research Institute, University of Ottawa, Ottawa, ON K1H 8M5, Canada
- Department of Neuropediatrics and Muscle Disorders, Faculty of Medicine, Medical Center-University of Freiburg, 79104 Freiburg, Germany
- Centro Nacional de Análisis Genómico (CNAG-CRG), Center for Genomic Regulation, Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Catalonia, Spain
| | - Rita Horvath
- Department of Clinical Neurosciences, University of Cambridge, Cambridge CB3 0FD, UK
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39
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Kuznetsov IA, Kuznetsov AV. ATP diffusional gradients are sufficient to maintain bioenergetic homeostasis in synaptic boutons lacking mitochondria. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2023; 39:e3696. [PMID: 36872253 DOI: 10.1002/cnm.3696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 02/16/2023] [Accepted: 02/20/2023] [Indexed: 05/13/2023]
Abstract
Previous work on mitochondrial distribution in axons has shown that approximately half of the presynaptic release sites do not contain mitochondria, raising the question of how the boutons that do not contain mitochondria are supplied with ATP. Here, we develop and apply a mathematical model to study this question. Specifically, we investigate whether diffusive transport of ATP is sufficient to support the exocytic functionality in synaptic boutons which lack mitochondria. Our results demonstrate that the difference in ATP concentration between a bouton containing a mitochondrion and a neighboring bouton lacking a mitochondrion is only approximately 0.4%, which is still 3.75 times larger than the ATP concentration minimally required to support synaptic vesicle release. This work therefore suggests that passive diffusion of ATP is sufficient to maintain the functionality of boutons which do not contain mitochondria.
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Affiliation(s)
- Ivan A Kuznetsov
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Andrey V Kuznetsov
- Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, North Carolina, USA
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40
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Li H, Guglielmetti C, Sei YJ, Zilberter M, Le Page LM, Shields L, Yang J, Nguyen K, Tiret B, Gao X, Bennett N, Lo I, Dayton TL, Kampmann M, Huang Y, Rathmell JC, Vander Heiden M, Chaumeil MM, Nakamura K. Neurons require glucose uptake and glycolysis in vivo. Cell Rep 2023; 42:112335. [PMID: 37027294 PMCID: PMC10556202 DOI: 10.1016/j.celrep.2023.112335] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/22/2023] [Accepted: 03/20/2023] [Indexed: 04/08/2023] Open
Abstract
Neurons require large amounts of energy, but whether they can perform glycolysis or require glycolysis to maintain energy remains unclear. Using metabolomics, we show that human neurons do metabolize glucose through glycolysis and can rely on glycolysis to supply tricarboxylic acid (TCA) cycle metabolites. To investigate the requirement for glycolysis, we generated mice with postnatal deletion of either the dominant neuronal glucose transporter (GLUT3cKO) or the neuronal-enriched pyruvate kinase isoform (PKM1cKO) in CA1 and other hippocampal neurons. GLUT3cKO and PKM1cKO mice show age-dependent learning and memory deficits. Hyperpolarized magnetic resonance spectroscopic (MRS) imaging shows that female PKM1cKO mice have increased pyruvate-to-lactate conversion, whereas female GLUT3cKO mice have decreased conversion, body weight, and brain volume. GLUT3KO neurons also have decreased cytosolic glucose and ATP at nerve terminals, with spatial genomics and metabolomics revealing compensatory changes in mitochondrial bioenergetics and galactose metabolism. Therefore, neurons metabolize glucose through glycolysis in vivo and require glycolysis for normal function.
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Affiliation(s)
- Huihui Li
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Caroline Guglielmetti
- Department of Physical Therapy and Rehabilitation Science, San Francisco, CA 94158, USA; Department of Radiology and Biomedical Imaging, San Francisco, CA 94158, USA
| | - Yoshitaka J Sei
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Misha Zilberter
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Lydia M Le Page
- Department of Physical Therapy and Rehabilitation Science, San Francisco, CA 94158, USA; Department of Radiology and Biomedical Imaging, San Francisco, CA 94158, USA
| | - Lauren Shields
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA; Graduate Program in Biomedical Sciences, University of California San Francisco, San Francisco, CA 94143, USA
| | - Joyce Yang
- Graduate Program in Neuroscience, University of California San Francisco, San Francisco, CA 94158, USA
| | - Kevin Nguyen
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Brice Tiret
- Department of Physical Therapy and Rehabilitation Science, San Francisco, CA 94158, USA; Department of Radiology and Biomedical Imaging, San Francisco, CA 94158, USA
| | - Xiao Gao
- Department of Physical Therapy and Rehabilitation Science, San Francisco, CA 94158, USA; Department of Radiology and Biomedical Imaging, San Francisco, CA 94158, USA; UCSF/UCB Graduate Program in Bioengineering, University of California San Francisco, San Francisco, CA 94158, USA
| | - Neal Bennett
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Iris Lo
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Talya L Dayton
- Koch Institute for Integrative Cancer Research and the Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Martin Kampmann
- Graduate Program in Biomedical Sciences, University of California San Francisco, San Francisco, CA 94143, USA; Graduate Program in Neuroscience, University of California San Francisco, San Francisco, CA 94158, USA; UCSF/UCB Graduate Program in Bioengineering, University of California San Francisco, San Francisco, CA 94158, USA; Institute for Neurodegenerative Diseases, University of California San Francisco, San Francisco, CA, USA; Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - Yadong Huang
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA; Graduate Program in Biomedical Sciences, University of California San Francisco, San Francisco, CA 94143, USA; Graduate Program in Neuroscience, University of California San Francisco, San Francisco, CA 94158, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Jeffrey C Rathmell
- Vanderbilt Center for Immunobiology, Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Matthew Vander Heiden
- Koch Institute for Integrative Cancer Research and the Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - Myriam M Chaumeil
- Department of Physical Therapy and Rehabilitation Science, San Francisco, CA 94158, USA; Department of Radiology and Biomedical Imaging, San Francisco, CA 94158, USA; Graduate Program in Biomedical Sciences, University of California San Francisco, San Francisco, CA 94143, USA; UCSF/UCB Graduate Program in Bioengineering, University of California San Francisco, San Francisco, CA 94158, USA.
| | - Ken Nakamura
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA; Graduate Program in Biomedical Sciences, University of California San Francisco, San Francisco, CA 94143, USA; Graduate Program in Neuroscience, University of California San Francisco, San Francisco, CA 94158, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA.
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41
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Perouansky M, Johnson-Schlitz D, Sedensky MM, Morgan PG. A primordial target: Mitochondria mediate both primary and collateral anesthetic effects of volatile anesthetics. Exp Biol Med (Maywood) 2023; 248:545-552. [PMID: 37208922 PMCID: PMC10350799 DOI: 10.1177/15353702231165025] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/21/2023] Open
Abstract
One of the unsolved mysteries of medicine is how do volatile anesthetics (VAs) cause a patient to reversibly lose consciousness. In addition, identifying mechanisms for the collateral effects of VAs, including anesthetic-induced neurotoxicity (AiN) and anesthetic preconditioning (AP), has proven challenging. Multiple classes of molecules (lipids, proteins, and water) have been considered as potential VA targets, but recently proteins have received the most attention. Studies targeting neuronal receptors or ion channels had limited success in identifying the critical targets of VAs mediating either the phenotype of "anesthesia" or their collateral effects. Recent studies in both nematodes and fruit flies may provide a paradigm shift by suggesting that mitochondria may harbor the upstream molecular switch activating both primary and collateral effects. The disruption of a specific step of electron transfer within the mitochondrion causes hypersensitivity to VAs, from nematodes to Drosophila and to humans, while also modulating the sensitivity to collateral effects. The downstream effects from mitochondrial inhibition are potentially legion, but inhibition of presynaptic neurotransmitter cycling appears to be specifically sensitive to the mitochondrial effects. These findings are perhaps of even broader interest since two recent reports indicate that mitochondrial damage may well underlie neurotoxic and neuroprotective effects of VAs in the central nervous system (CNS). It is, therefore, important to understand how anesthetics interact with mitochondria to affect CNS function, not just for the desired facets of general anesthesia but also for significant collateral effects, both harmful and beneficial. A tantalizing possibility exists that both the primary (anesthesia) and secondary (AiN, AP) mechanisms may at least partially overlap in the mitochondrial electron transport chain (ETC).
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Affiliation(s)
- Misha Perouansky
- Department of Anesthesiology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53792, USA
- Laboratory of Genetics, School of Medicine and Public Health and College of Agricultural and Life Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Dena Johnson-Schlitz
- Department of Anesthesiology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53792, USA
| | - Margaret M Sedensky
- Department of Anesthesiology and Pain Medicine, University of Washington School of Medicine, Seattle, WA 98101, USA
| | - Philip G Morgan
- Department of Anesthesiology and Pain Medicine, University of Washington School of Medicine, Seattle, WA 98101, USA
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42
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Oxygen-Glucose Deprivation Decreases the Motility and Length of Axonal Mitochondria in Cultured Dorsal Root Ganglion Cells of Rats. Cell Mol Neurobiol 2023; 43:1267-1280. [PMID: 35771293 DOI: 10.1007/s10571-022-01247-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 06/20/2022] [Indexed: 11/03/2022]
Abstract
Controlling axonal mitochondria is important for maintaining normal function of the neural network. Oxygen-glucose deprivation (OGD), a model used for mimicking ischemia, eventually induces neuronal cell death similar to axonal degeneration. Axonal mitochondria are disrupted during OGD-induced neural degeneration; however, the mechanism underlying mitochondrial dysfunction has not been completely understood. We focused on the dynamics of mitochondria in axons exposed to OGD; we observed that the number of motile mitochondria significantly reduced in 1 h following OGD exposure. In our observation, the decreased length of stationary mitochondria was affected by the following factors: first, the halt of motile mitochondria; second, the fission of longer stationary mitochondria; and third, a transformation from tubular to spherical shape in OGD-exposed axons. Motile mitochondria reduction preceded stationary mitochondria fragmentation in OGD exposure; these conditions induced the decrease of stationary mitochondria in three different ways. Our results suggest that mitochondrial morphological changes precede the axonal degeneration while ischemia-induced neurodegeneration.
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43
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Wang W, Zhao F, Lu Y, Siedlak SL, Fujioka H, Feng H, Perry G, Zhu X. Damaged mitochondria coincide with presynaptic vesicle loss and abnormalities in alzheimer's disease brain. Acta Neuropathol Commun 2023; 11:54. [PMID: 37004141 PMCID: PMC10067183 DOI: 10.1186/s40478-023-01552-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 03/16/2023] [Indexed: 04/03/2023] Open
Abstract
Loss of synapses is the most robust pathological correlate of Alzheimer's disease (AD)-associated cognitive deficits, although the underlying mechanism remains incompletely understood. Synaptic terminals have abundant mitochondria which play an indispensable role in synaptic function through ATP provision and calcium buffering. Mitochondrial dysfunction is an early and prominent feature in AD which could contribute to synaptic deficits. Here, using electron microscopy, we examined synapses with a focus on mitochondrial deficits in presynaptic axonal terminals and dendritic spines in cortical biopsy samples from clinically diagnosed AD and age-matched non-AD control patients. Synaptic vesicle density within the presynaptic axon terminals was significantly decreased in AD cases which appeared largely due to significantly decreased reserve pool, but there were significantly more presynaptic axons containing enlarged synaptic vesicles or dense core vesicles in AD. Importantly, there was reduced number of mitochondria along with significantly increased damaged mitochondria in the presynapse of AD which correlated with changes in SV density. Mitochondria in the post-synaptic dendritic spines were also enlarged and damaged in the AD biopsy samples. This study provided evidence of presynaptic vesicle loss as synaptic deficits in AD and suggested that mitochondrial dysfunction in both pre- and post-synaptic compartments contribute to synaptic deficits in AD.
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Affiliation(s)
- Wenzhang Wang
- Department of Pathology, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH, 44106, USA
| | - Fanpeng Zhao
- Department of Pathology, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH, 44106, USA
| | - Yubing Lu
- Department of Pathology, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH, 44106, USA
| | - Sandra L Siedlak
- Department of Pathology, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH, 44106, USA
| | - Hisashi Fujioka
- Cryo-EM Core Facility, Case Western Reserve University, Cleveland, OH, USA
| | - Hao Feng
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, Cleveland, OH, USA
| | - George Perry
- Department of Neuroscience, Developmental and Regenerative Biology, University of Texas, San Antonio, TX, USA
| | - Xiongwei Zhu
- Department of Pathology, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH, 44106, USA.
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44
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Rumpf S, Sanal N, Marzano M. Energy metabolic pathways in neuronal development and function. OXFORD OPEN NEUROSCIENCE 2023; 2:kvad004. [PMID: 38596236 PMCID: PMC10913822 DOI: 10.1093/oons/kvad004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 03/18/2023] [Accepted: 03/20/2023] [Indexed: 04/11/2024]
Abstract
Neuronal development and function are known to be among the most energy-demanding functions of the body. Constant energetic support is therefore crucial at all stages of a neuron's life. The two main adenosine triphosphate (ATP)-producing pathways in cells are glycolysis and oxidative phosphorylation. Glycolysis has a relatively low yield but provides fast ATP and enables the metabolic versatility needed in dividing neuronal stem cells. Oxidative phosphorylation, on the other hand, is highly efficient and therefore thought to provide most or all ATP in differentiated neurons. However, it has recently become clear that due to their distinct properties, both pathways are required to fully satisfy neuronal energy demands during development and function. Here, we provide an overview of how glycolysis and oxidative phosphorylation are used in neurons during development and function.
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Affiliation(s)
- Sebastian Rumpf
- Correspondence address. Multiscale Imaging Center, University of Münster, Röntgenstrasse 16, 48149 Münster, Germany. E-mail:
| | - Neeraja Sanal
- Multiscale Imaging Center, University of Münster, Röntgenstrasse 16, 48149 Münster, Germany
| | - Marco Marzano
- Multiscale Imaging Center, University of Münster, Röntgenstrasse 16, 48149 Münster, Germany
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The Combination of Baicalein and Memantine Reduces Oxidative Stress and Protects against β-amyloid-Induced Alzheimer’s Disease in Rat Model. Antioxidants (Basel) 2023; 12:antiox12030707. [PMID: 36978955 PMCID: PMC10045767 DOI: 10.3390/antiox12030707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 02/24/2023] [Accepted: 03/01/2023] [Indexed: 03/16/2023] Open
Abstract
Alzheimer’s disease (AD) is a neuronal condition causing progressive loss of memory and cognitive dysfunction particularly in elders. An upsurge in the global old age population has led to a proportionate increase in the prevalence of AD. The current treatments for AD are symptomatic and have debilitating side effects. A literature review and current research have directed scientists to explore natural products with better safety and efficacy profiles as new treatment options for AD. Baicalein, belonging to the flavone subclass of flavonoids, has been reported for its anti-oxidant, anti-inflammatory, AChE enzyme inhibitory activity and anti-amyloid protein aggregation activity, which collectively demonstrates its benefits as a neuroprotective agent. Presently, memantine, a NMDAR antagonist, is one of the important drugs used for treatment of Alzheimer’s disease. The current study aims to investigate the effect of baicalein in combination with memantine in β-amyloid-induced AD in albino Wistar rats. Baicalein (10 mg/kg) alone, 5 mg/kg and 10 mg/kg in combination with memantine (20 mg/kg) was administered for 21 days. Treatment with baicalein in combination with memantine showed significant improvement in behavioural studies. The combination treatment decreased oxidative stress, β-amyloid plaque formation and increased the expression of brain-derived neurotrophic factor (BDNF) in the brain. From the results, it can be concluded that treatment with baicalein and memantine could be beneficial for reducing the progression of neurodegeneration in rats. Baicalein has an additive effect in combination with memantine, making it a potential option for the treatment of AD.
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Tiwari A, Hashemiaghdam A, Laramie MA, Maschi D, Haddad T, Stunault MI, Bergom C, Javaheri A, Klyachko V, Ashrafi G. Sirtuin3 ensures the metabolic plasticity of neurotransmission during glucose deprivation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.08.531724. [PMID: 36945567 PMCID: PMC10028948 DOI: 10.1101/2023.03.08.531724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
Neurotransmission is an energetically expensive process that underlies cognition. During intense electrical activity or dietary restrictions, glucose levels in the brain plummet, forcing neurons to utilize alternative fuels. However, the molecular mechanisms of neuronal metabolic plasticity remain poorly understood. Here, we demonstrate that glucose-deprived neurons activate the CREB and PGC1α transcriptional program that induces the expression of the mitochondrial deacetylase Sirtuin 3 (Sirt3) both in vitro and in vivo . We show that Sirt3 localizes to axonal mitochondria and stimulates mitochondrial oxidative capacity in hippocampal nerve terminals. Sirt3 plays an essential role in sustaining synaptic transmission in the absence of glucose by powering the retrieval of synaptic vesicles after release. These results demonstrate that the transcriptional induction of Sirt3 ensures the metabolic plasticity of synaptic transmission. Highlights Glucose deprivation drives transcriptional reprogramming of neuronal metabolism via CREB and PGC1α. Glucose or food deprivation trigger the neuronal expression of mitochondrial deacetylase sirtuin 3 (Sirt3) both in vitro and in vivo . Sirt3 stimulates oxidative ATP synthesis in nerve terminals.Sirt3 sustains the synaptic vesicle cycle in the absence of glucose.
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47
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Xue L, Schnacke P, Frei MS, Koch B, Hiblot J, Wombacher R, Fabritz S, Johnsson K. Probing coenzyme A homeostasis with semisynthetic biosensors. Nat Chem Biol 2023; 19:346-355. [PMID: 36316571 PMCID: PMC9974488 DOI: 10.1038/s41589-022-01172-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 09/13/2022] [Indexed: 11/07/2022]
Abstract
Coenzyme A (CoA) is one of the central cofactors of metabolism, yet a method for measuring its concentration in living cells is missing. Here we introduce the first biosensor for measuring CoA levels in different organelles of mammalian cells. The semisynthetic biosensor is generated through the specific labeling of an engineered GFP-HaloTag fusion protein with a fluorescent ligand. Its readout is based on CoA-dependent changes in Förster resonance energy transfer efficiency between GFP and the fluorescent ligand. Using this biosensor, we probe the role of numerous proteins involved in CoA biosynthesis and transport in mammalian cells. On the basis of these studies, we propose a cellular map of CoA biosynthesis that suggests how pools of cytosolic and mitochondrial CoA are maintained.
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Affiliation(s)
- Lin Xue
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany.
- MOE Key Laboratory for Cellular Dynamics, Hefei National Center for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, China.
| | - Paul Schnacke
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Michelle S Frei
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Birgit Koch
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Julien Hiblot
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Richard Wombacher
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Sebastian Fabritz
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Kai Johnsson
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany.
- Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
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48
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Kuznetsov IA, Kuznetsov AV. Mitochondrial Transport in Axons with Multiple Branching Junctions: A Computational Study. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.22.529604. [PMID: 36865162 PMCID: PMC9980112 DOI: 10.1101/2023.02.22.529604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
We explore the impact of multiple branching junctions in axons on the mean age of mitochondria and their age density distributions in demand sites. The study looked at mitochondrial concentration, mean age, and age density distribution in relation to the distance from the soma. We developed models for a symmetric axon containing 14 demand sites and an asymmetric axon containing 10 demand sites. We examined how the concentration of mitochondria changes when an axon is divided into two branches at the branching junction. We also studied whether mitochondria concentrations in the branches are affected by what portion of mitochondrial flux goes into the upper branch and what portion goes into the lower branch. Additionally, we explored whether the distributions of mitochondria mean age and age density in branching axons are affected by how the mitochondria flux splits at the branching junction. Our findings elucidate the effects of axonal branching on mitochondria age. Mitochondria aging is the focus of this study as recent research suggests it may be involved in neurodegenerative disorders.
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49
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Sebastian MJ, Khan SKA, Pappachan JM, Jeeyavudeen MS. Diabetes and cognitive function: An evidence-based current perspective. World J Diabetes 2023; 14:92-109. [PMID: 36926658 PMCID: PMC10011899 DOI: 10.4239/wjd.v14.i2.92] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 12/26/2022] [Accepted: 01/17/2023] [Indexed: 02/14/2023] Open
Abstract
Several epidemiological studies have clearly identified diabetes mellitus (DM) as a major risk factor for cognitive dysfunction, and it is going to be a major public health issue in the coming years because of the alarming rise in diabetes prevalence across the world. Brain and neural tissues predominantly depend on glucose as energy substrate and hence, any alterations in carbohydrate meta-bolism can directly impact on cerebral functional output including cognition, executive capacity, and memory. DM affects neuronal function and mental capacity in several ways, some of which include hypoperfusion of the brain tissues from cerebrovascular disease, diabetes-related alterations of glucose transporters causing abnormalities in neuronal glucose uptake and metabolism, local hyper- and hypometabolism of brain areas from insulin resistance, and recurrent hypoglycemic episodes inherent to pharmacotherapy of diabetes resulting in neuronal damage. Cognitive decline can further worsen diabetes care as DM is a disease largely self-managed by patients. Therefore, it is crucial to understand the pathobiology of cognitive dysfunction in relation to DM and its management for optimal long-term care plan for patients. A thorough appraisal of normal metabolic characteristics of the brain, how alterations in neural metabolism affects cognition, the diagnostic algorithm for patients with diabetes and dementia, and the management and prognosis of patients when they have this dangerous combination of illnesses is imperative in this context. This evidence-based narrative with the back-up of latest clinical trial reviews elaborates the current understanding on diabetes and cognitive function to empower physicians to manage their patients in day-to-day clinical practice.
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Affiliation(s)
| | - Shahanas KA Khan
- Department of Endocrinology and Metabolism, Lancashire Teaching Hospitals NHS Trust, Preston PR2 9HT, United Kingdom
| | - Joseph M Pappachan
- Department of Endocrinology and Metabolism, Lancashire Teaching Hospitals NHS Trust, Preston PR2 9HT, United Kingdom
- Faculty of Science, Manchester Metropolitan University, Manchester M15 6BH, United Kingdom
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - Mohammad Sadiq Jeeyavudeen
- Department of Endocrinology and Metabolism, University Hospitals of Edinburgh, Edinburgh EH16 4SA, United Kingdom
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50
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Pizcueta P, Vergara C, Emanuele M, Vilalta A, Rodríguez-Pascau L, Martinell M. Development of PPARγ Agonists for the Treatment of Neuroinflammatory and Neurodegenerative Diseases: Leriglitazone as a Promising Candidate. Int J Mol Sci 2023; 24:ijms24043201. [PMID: 36834611 PMCID: PMC9961553 DOI: 10.3390/ijms24043201] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 01/21/2023] [Accepted: 02/01/2023] [Indexed: 02/08/2023] Open
Abstract
Increasing evidence suggests that the peroxisome proliferator-activated receptor γ (PPARγ), a member of the nuclear receptor superfamily, plays an important role in physiological processes in the central nervous system (CNS) and is involved in cellular metabolism and repair. Cellular damage caused by acute brain injury and long-term neurodegenerative disorders is associated with alterations of these metabolic processes leading to mitochondrial dysfunction, oxidative stress, and neuroinflammation. PPARγ agonists have demonstrated the potential to be effective treatments for CNS diseases in preclinical models, but to date, most drugs have failed to show efficacy in clinical trials of neurodegenerative diseases including amyotrophic lateral sclerosis, Parkinson's disease, and Alzheimer's disease. The most likely explanation for this lack of efficacy is the insufficient brain exposure of these PPARγ agonists. Leriglitazone is a novel, blood-brain barrier (BBB)-penetrant PPARγ agonist that is being developed to treat CNS diseases. Here, we review the main roles of PPARγ in physiology and pathophysiology in the CNS, describe the mechanism of action of PPARγ agonists, and discuss the evidence supporting the use of leriglitazone to treat CNS diseases.
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Affiliation(s)
- Pilar Pizcueta
- Minoryx Therapeutics SL, 08302 Barcelona, Spain
- Correspondence:
| | | | - Marco Emanuele
- Minoryx Therapeutics BE, Gosselies, 6041 Charleroi, Belgium
| | | | | | - Marc Martinell
- Minoryx Therapeutics SL, 08302 Barcelona, Spain
- Minoryx Therapeutics BE, Gosselies, 6041 Charleroi, Belgium
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