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Kaye SD, Goyani S, Tomar D. MICU1's calcium sensing beyond mitochondrial calcium uptake. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119714. [PMID: 38555977 PMCID: PMC11194792 DOI: 10.1016/j.bbamcr.2024.119714] [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: 12/28/2023] [Revised: 03/19/2024] [Accepted: 03/21/2024] [Indexed: 04/02/2024]
Abstract
The discovery of MICU1 as gatekeeper of mitochondrial calcium (mCa2+) entry has transformed our understanding of mCa2+ flux. Recent studies revealed an additional role of MICU1 as a Ca2+ sensor at MICOS (mitochondrial contact site and cristae organizing system). MICU1's presence at MICOS suggests its involvement in coordinating Ca2+ signaling and mitochondrial ultrastructure. Besides its role in Ca2+ regulation, MICU1 influences cellular signaling pathways including transcription, epigenetic regulation, metabolism, and cell death, thereby affecting human health. Here, we summarize recent findings on MICU1's canonical and noncanonical functions, and its relevance to human health and diseases.
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Affiliation(s)
- Sarah D Kaye
- Department of Internal Medicine, Section of Gerontology and Geriatric Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Shanikumar Goyani
- Department of Internal Medicine, Section of Cardiovascular Medicine, Section of Molecular Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Dhanendra Tomar
- Department of Internal Medicine, Section of Cardiovascular Medicine, Section of Molecular Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.
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2
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Huo J, Molkentin JD. MCU genetically altered mice suggest how mitochondrial Ca 2+ regulates metabolism. Trends Endocrinol Metab 2024:S1043-2760(24)00088-2. [PMID: 38688781 DOI: 10.1016/j.tem.2024.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 04/03/2024] [Accepted: 04/04/2024] [Indexed: 05/02/2024]
Abstract
Skeletal muscle has a major impact on total body metabolism and obesity, and is characterized by dynamic regulation of substrate utilization. While it is accepted that acute increases in mitochondrial matrix Ca2+ increase carbohydrate usage to augment ATP production, recent studies in mice with deleted genes for components of the mitochondrial Ca2+ uniporter (MCU) complex have suggested a more complicated regulatory scenario. Indeed, mice with a deleted Mcu gene in muscle, which lack acute mitochondrial Ca2+ uptake, have greater fatty acid oxidation (FAO) and less adiposity. By contrast, mice deleted for the inhibitory Mcub gene in skeletal muscle, which have greater acute mitochondrial Ca2+ uptake, antithetically display reduced FAO and progressive obesity. In this review we discuss the emerging concept that dynamic fluxing of mitochondrial matrix Ca2+ regulates metabolism.
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Affiliation(s)
- Jiuzhou Huo
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Jeffery D Molkentin
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA.
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3
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Finsterer J, Barwari A. Dolichocephaly, Arachnodactyly, Diplopia, and Distal Myopathy - Novel Phenotype of MICU1 Variant c.553C>T. Cureus 2024; 16:e52672. [PMID: 38380193 PMCID: PMC10878678 DOI: 10.7759/cureus.52672] [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] [Accepted: 01/21/2024] [Indexed: 02/22/2024] Open
Abstract
Pathogenic variants in mitochondrial calcium uptake 1 (MICU1) manifest phenotypically heterogeneously but most frequently in the brain and skeletal muscle. Dolichocephaly, arachnodactyly, diplopia, and distal myopathy have not been reported in carriers of a pathogenic MICU1 variant. The patient is a 23-year-old female with consanguineous parents (first cousins) who was a carrier of the homozygous MICU1 variant c.553C>T, phenotypically presenting with developmental delay, intellectual disability, ataxia, dysmorphia (dolichocephaly, arachnodactyly, clinodactyly, hypertelorism, wide nasal bridge), myopathy (ptosis, double vision, strabismus, distal limb weakness, diffuse wasting, hypotonia), hyperextensible joints and hyperkyphosis. Features not previously described were dolichocephaly, arachnodactyly, broad nasal bridge, double vision, and distal myopathy. She was treated with physical therapy, speech therapy, and occupational therapy and received escitalopram and mirtazapine for concomitant depression, anxiety disorder, and insomnia. The presented case shows that the phenotypic heterogeneity of pathogenic MICU1 variants is even greater than previously assumed. Treatment of MICU1-related phenotypes is symptomatic, but these patients benefit from physical therapy, behavioral therapy, speech therapy, and antidepressant treatment.
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Affiliation(s)
- Josef Finsterer
- Neurology, Neurology and Neurophysiology Center, Vienna, AUT
| | - Awini Barwari
- Neurology, Neurology and Neurophysiology Center, Vienna, AUT
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Li X, Sun B, Li J, Ye W, Li M, Guan F, Wu S, Luo X, Feng J, Jia J, Liu X, Li T, Liu L. SEPSIS LEADS TO IMPAIRED MITOCHONDRIAL CALCIUM UPTAKE AND SKELETAL MUSCLE WEAKNESS BY REDUCING THE MICU1:MCU PROTEIN RATIO. Shock 2023; 60:698-706. [PMID: 37695737 PMCID: PMC10662578 DOI: 10.1097/shk.0000000000002221] [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: 05/02/2023] [Revised: 05/23/2023] [Accepted: 08/29/2023] [Indexed: 09/13/2023]
Abstract
ABSTRACT Purpose: Intensive care unit-acquired weakness (ICUAW) is a severe neuromuscular complication that frequently occurs in patients with sepsis. The precise molecular pathophysiology of mitochondrial calcium uptake 1 (MICU1) and mitochondrial calcium uniporter (MCU) in ICUAW has not been fully elucidated. Here, we speculate that ICUAW is associated with MICU1:MCU protein ratio-mediated mitochondrial calcium ([Ca 2+ ] m ) uptake dysfunction. Methods: Cecal ligation and perforation (CLP) was performed on C57BL/6J mice to induce sepsis. Sham-operated animals were used as controls. Lipopolysaccharide (LPS) (5 μg/mL) was used to induce inflammation in differentiated C2C12 myoblasts. Compound muscle action potential (CMAP) was detected using a biological signal acquisition system. Grip strength was measured using a grip-strength meter. Skeletal muscle inflammatory factors were detected using ELISA kits. The cross-sectional area (CSA) of the tibialis anterior (TA) muscle was detected by hematoxylin and eosin staining. Cytosolic calcium ([Ca 2+ ] c ) levels were measured using Fluo-4 AM. Adeno-associated virus (AAV) was injected into TA muscles for 4 weeks to overexpress MICU1 prophylactically. A lentivirus was used to infect C2C12 cells to increase MICU1 expression prophylactically. Findings: The results suggest that sepsis induces [Ca 2+ ] m uptake disorder by reducing the MICU1:MCU protein ratio, resulting in skeletal muscle weakness and muscle fiber atrophy. However, MICU1 prophylactic overexpression reversed these effects by increasing the MICU1:MCU protein ratio. Conclusions: ICUAW is associated with impaired [Ca 2+ ] m uptake caused by a decreased MICU1:MCU protein ratio. MICU1 overexpression improves sepsis-induced skeletal muscle weakness and atrophy by ameliorating the [Ca 2+ ] m uptake disorder.
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Affiliation(s)
- Xuexin Li
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Bowen Sun
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Jie Li
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Wanlin Ye
- Laboratory of Mitochondria and Metabolism, West China Hospital of Sichuan University, Chengdu, China
| | - Mingjuan Li
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Fasheng Guan
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Songlin Wu
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Xuerong Luo
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Jianguo Feng
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Jing Jia
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Xueru Liu
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Tao Li
- Laboratory of Mitochondria and Metabolism, West China Hospital of Sichuan University, Chengdu, China
| | - Li Liu
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
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Shi X, Liu C, Chen J, Zhou S, Li Y, Zhao X, Xing J, Xue J, Liu F, Li F. Endothelial MICU1 alleviates diabetic cardiomyopathy by attenuating nitrative stress-mediated cardiac microvascular injury. Cardiovasc Diabetol 2023; 22:216. [PMID: 37592255 PMCID: PMC10436431 DOI: 10.1186/s12933-023-01941-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 07/25/2023] [Indexed: 08/19/2023] Open
Abstract
BACKGROUND Myocardial microvascular injury is the key event in early diabetic heart disease. The injury of myocardial microvascular endothelial cells (CMECs) is the main cause and trigger of myocardial microvascular disease. Mitochondrial calcium homeostasis plays an important role in maintaining the normal function, survival and death of endothelial cells. Considering that mitochondrial calcium uptake 1 (MICU1) is a key molecule in mitochondrial calcium regulation, this study aimed to investigate the role of MICU1 in CMECs and explore its underlying mechanisms. METHODS To examine the role of endothelial MICU1 in diabetic cardiomyopathy (DCM), we used endothelial-specific MICU1ecKO mice to establish a diabetic mouse model and evaluate the cardiac function. In addition, MICU1 overexpression was conducted by injecting adeno-associated virus 9 carrying MICU1 (AAV9-MICU1). Transcriptome sequencing technology was used to explore underlying molecular mechanisms. RESULTS Here, we found that MICU1 expression is decreased in CMECs of diabetic mice. Moreover, we demonstrated that endothelial cell MICU1 knockout exacerbated the levels of cardiac hypertrophy and interstitial myocardial fibrosis and led to a further reduction in left ventricular function in diabetic mice. Notably, we found that AAV9-MICU1 specifically upregulated the expression of MICU1 in CMECs of diabetic mice, which inhibited nitrification stress, inflammatory reaction, and apoptosis of the CMECs, ameliorated myocardial hypertrophy and fibrosis, and promoted cardiac function. Further mechanistic analysis suggested that MICU1 deficiency result in excessive mitochondrial calcium uptake and homeostasis imbalance which caused nitrification stress-induced endothelial damage and inflammation that disrupted myocardial microvascular endothelial barrier function and ultimately promoted DCM progression. CONCLUSIONS Our findings demonstrate that MICU1 expression was downregulated in the CMECs of diabetic mice. Overexpression of endothelial MICU1 reduced nitrification stress induced apoptosis and inflammation by inhibiting mitochondrial calcium uptake, which improved myocardial microvascular function and inhibited DCM progression. Our findings suggest that endothelial MICU1 is a molecular intervention target for the potential treatment of DCM.
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Affiliation(s)
- Xide Shi
- Department of Cardiology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Chao Liu
- Department of Cardiology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Jiangwei Chen
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Clinical Research Center for Oral Diseases, Department of Medical Rehabilitation, School of Stomatology, The Fourth Military Medical University, Xi'an, China
| | - Shiqiang Zhou
- Department of Cardiology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Yajuan Li
- Aerospace Clinical Medical Center, School of Aerospace Medicine, The Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, Shaanxi, China
| | - Xingcheng Zhao
- Aerospace Clinical Medical Center, School of Aerospace Medicine, The Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, Shaanxi, China
| | - Jinliang Xing
- Department of Physiology and Pathophysiology, State Key Laboratory of Cancer Biology, The Fourth Military Medical University, Xi'an, China
| | - Junhui Xue
- Aerospace Clinical Medical Center, School of Aerospace Medicine, The Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, Shaanxi, China.
- Department of Aviation Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.
| | - Fengzhou Liu
- Aerospace Clinical Medical Center, School of Aerospace Medicine, The Fourth Military Medical University, 169 Changle West Road, Xi'an, 710032, Shaanxi, China.
- Department of Aviation Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.
| | - Fei Li
- Department of Cardiology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.
- Department of Aviation Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.
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Kadam A, Jadiya P, Tomar D. Post-translational modifications and protein quality control of mitochondrial channels and transporters. Front Cell Dev Biol 2023; 11:1196466. [PMID: 37601094 PMCID: PMC10434574 DOI: 10.3389/fcell.2023.1196466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 07/24/2023] [Indexed: 08/22/2023] Open
Abstract
Mitochondria play a critical role in energy metabolism and signal transduction, which is tightly regulated by proteins, metabolites, and ion fluxes. Metabolites and ion homeostasis are mainly mediated by channels and transporters present on mitochondrial membranes. Mitochondria comprise two distinct compartments, the outer mitochondrial membrane (OMM) and the inner mitochondrial membrane (IMM), which have differing permeabilities to ions and metabolites. The OMM is semipermeable due to the presence of non-selective molecular pores, while the IMM is highly selective and impermeable due to the presence of specialized channels and transporters which regulate ion and metabolite fluxes. These channels and transporters are modulated by various post-translational modifications (PTMs), including phosphorylation, oxidative modifications, ions, and metabolites binding, glycosylation, acetylation, and others. Additionally, the mitochondrial protein quality control (MPQC) system plays a crucial role in ensuring efficient molecular flux through the mitochondrial membranes by selectively removing mistargeted or defective proteins. Inefficient functioning of the transporters and channels in mitochondria can disrupt cellular homeostasis, leading to the onset of various pathological conditions. In this review, we provide a comprehensive overview of the current understanding of mitochondrial channels and transporters in terms of their functions, PTMs, and quality control mechanisms.
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Affiliation(s)
- Ashlesha Kadam
- Department of Internal Medicine, Section of Cardiovascular Medicine, Section of Molecular Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Pooja Jadiya
- Department of Internal Medicine, Section of Gerontology and Geriatric Medicine, Section of Molecular Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Dhanendra Tomar
- Department of Internal Medicine, Section of Cardiovascular Medicine, Section of Molecular Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
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Novorolsky RJ, Kasheke GDS, Hakim A, Foldvari M, Dorighello GG, Sekler I, Vuligonda V, Sanders ME, Renden RB, Wilson JJ, Robertson GS. Preserving and enhancing mitochondrial function after stroke to protect and repair the neurovascular unit: novel opportunities for nanoparticle-based drug delivery. Front Cell Neurosci 2023; 17:1226630. [PMID: 37484823 PMCID: PMC10360135 DOI: 10.3389/fncel.2023.1226630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 06/22/2023] [Indexed: 07/25/2023] Open
Abstract
The neurovascular unit (NVU) is composed of vascular cells, glia, and neurons that form the basic component of the blood brain barrier. This intricate structure rapidly adjusts cerebral blood flow to match the metabolic needs of brain activity. However, the NVU is exquisitely sensitive to damage and displays limited repair after a stroke. To effectively treat stroke, it is therefore considered crucial to both protect and repair the NVU. Mitochondrial calcium (Ca2+) uptake supports NVU function by buffering Ca2+ and stimulating energy production. However, excessive mitochondrial Ca2+ uptake causes toxic mitochondrial Ca2+ overloading that triggers numerous cell death pathways which destroy the NVU. Mitochondrial damage is one of the earliest pathological events in stroke. Drugs that preserve mitochondrial integrity and function should therefore confer profound NVU protection by blocking the initiation of numerous injury events. We have shown that mitochondrial Ca2+ uptake and efflux in the brain are mediated by the mitochondrial Ca2+ uniporter complex (MCUcx) and sodium/Ca2+/lithium exchanger (NCLX), respectively. Moreover, our recent pharmacological studies have demonstrated that MCUcx inhibition and NCLX activation suppress ischemic and excitotoxic neuronal cell death by blocking mitochondrial Ca2+ overloading. These findings suggest that combining MCUcx inhibition with NCLX activation should markedly protect the NVU. In terms of promoting NVU repair, nuclear hormone receptor activation is a promising approach. Retinoid X receptor (RXR) and thyroid hormone receptor (TR) agonists activate complementary transcriptional programs that stimulate mitochondrial biogenesis, suppress inflammation, and enhance the production of new vascular cells, glia, and neurons. RXR and TR agonism should thus further improve the clinical benefits of MCUcx inhibition and NCLX activation by increasing NVU repair. However, drugs that either inhibit the MCUcx, or stimulate the NCLX, or activate the RXR or TR, suffer from adverse effects caused by undesired actions on healthy tissues. To overcome this problem, we describe the use of nanoparticle drug formulations that preferentially target metabolically compromised and damaged NVUs after an ischemic or hemorrhagic stroke. These nanoparticle-based approaches have the potential to improve clinical safety and efficacy by maximizing drug delivery to diseased NVUs and minimizing drug exposure in healthy brain and peripheral tissues.
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Affiliation(s)
- Robyn J. Novorolsky
- Department of Pharmacology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
- Brain Repair Centre, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Gracious D. S. Kasheke
- Department of Pharmacology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
- Brain Repair Centre, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Antoine Hakim
- School of Pharmacy, Faculty of Science, University of Waterloo, Waterloo, ON, Canada
| | - Marianna Foldvari
- School of Pharmacy, Faculty of Science, University of Waterloo, Waterloo, ON, Canada
| | - Gabriel G. Dorighello
- Department of Pharmacology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
- Brain Repair Centre, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Israel Sekler
- Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben Gurion University, Beersheva, Israel
| | | | | | - Robert B. Renden
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, United States
| | - Justin J. Wilson
- Department of Chemistry and Chemical Biology, College of Arts and Sciences, Cornell University, Ithaca, NY, United States
| | - George S. Robertson
- Department of Pharmacology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
- Brain Repair Centre, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
- Department of Psychiatry, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
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8
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Finsterer J. Autosomal Recessive Mitochondrial Myopathy due to MICU-1 Variants. Ann Indian Acad Neurol 2023; 26:567-568. [PMID: 37970264 PMCID: PMC10645233 DOI: 10.4103/aian.aian_383_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 06/12/2023] [Indexed: 11/17/2023] Open
Affiliation(s)
- Josef Finsterer
- Department of Neurological, Neurology and Neurophysiology Center, Vienna, Austria
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9
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Rodríguez-Prados M, Huang KT, Márta K, Paillard M, Csordás G, Joseph SK, Hajnóczky G. MICU1 controls the sensitivity of the mitochondrial Ca 2+ uniporter to activators and inhibitors. Cell Chem Biol 2023; 30:606-617.e4. [PMID: 37244260 PMCID: PMC10370359 DOI: 10.1016/j.chembiol.2023.05.002] [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: 10/06/2022] [Revised: 02/28/2023] [Accepted: 05/05/2023] [Indexed: 05/29/2023]
Abstract
Mitochondrial Ca2+ homeostasis loses its control in many diseases and might provide therapeutic targets. Mitochondrial Ca2+ uptake is mediated by the uniporter channel (mtCU), formed by MCU and is regulated by the Ca2+-sensing gatekeeper, MICU1, which shows tissue-specific stoichiometry. An important gap in knowledge is the molecular mechanism of the mtCU activators and inhibitors. We report that all pharmacological activators of the mtCU (spermine, kaempferol, SB202190) act in a MICU1-dependent manner, likely by binding to MICU1 and preventing MICU1's gatekeeping activity. These agents also sensitized the mtCU to inhibition by Ru265 and enhanced the Mn2+-induced cytotoxicity as previously seen with MICU1 deletion. Thus, MCU gating by MICU1 is the target of mtCU agonists and is a barrier for inhibitors like RuRed/Ru360/Ru265. The varying MICU1:MCU ratios result in different outcomes for both mtCU agonists and antagonists in different tissues, which is relevant for both pre-clinical research and therapeutic efforts.
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Affiliation(s)
- Macarena Rodríguez-Prados
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Kai-Ting Huang
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Katalin Márta
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Melanie Paillard
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - György Csordás
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Suresh K Joseph
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - György Hajnóczky
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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10
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Rodríguez-Prados M, Berezhnaya E, Castromonte MT, Menezes-Filho SL, Paillard M, Hajnóczky G. MICU1 occludes the mitochondrial calcium uniporter in divalent-free conditions. Proc Natl Acad Sci U S A 2023; 120:e2218999120. [PMID: 37126688 PMCID: PMC10175726 DOI: 10.1073/pnas.2218999120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Accepted: 03/30/2023] [Indexed: 05/03/2023] Open
Abstract
Mitochondrial Ca2+ uptake is mediated by the mitochondrial uniporter complex (mtCU) that includes a tetramer of the pore-forming subunit, MCU, a scaffold protein, EMRE, and the EF-hand regulatory subunit, MICU1 either homodimerized or heterodimerized with MICU2/3. MICU1 has been proposed to regulate Ca2+ uptake via the mtCU by physically occluding the pore and preventing Ca2+ flux at resting cytoplasmic [Ca2+] (free calcium concentration) and to increase Ca2+ flux at high [Ca2+] due to cooperative activation of MICUs EF-hands. However, mtCU and MICU1 functioning when its EF-hands are unoccupied by Ca2+ is poorly studied due to technical limitations. To overcome this barrier, we have studied the mtCU in divalent-free conditions by assessing the Ru265-sensitive Na+ influx using fluorescence-based measurement of mitochondrial matrix [Na+] (free sodium concentration) rise and the ensuing depolarization and swelling. We show an increase in all these measures of Na+ uptake in MICU1KO cells as compared to wild-type (WT) and rescued MICU1KO HEK cells. However, mitochondria in WT cells and MICU1 stable-rescued cells still allowed some Ru265-sensitive Na+ influx that was prevented by MICU1 in excess upon acute overexpression. Thus, MICU1 restricts the cation flux across the mtCU in the absence of Ca2+, but even in cells with high endogenous MICU1 expression such as HEK, some mtCU seem to lack MICU1-dependent gating. We also show rearrangement of the mtCU and altered number of functional channels in MICU1KO and different rescues, and loss of MICU1 during mitoplast preparation, that together might have obscured the pore-blocking function of MICU1 in divalent-free conditions in previous studies.
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Affiliation(s)
- Macarena Rodríguez-Prados
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA19107
| | - Elena Berezhnaya
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA19107
| | - Maria Teresa Castromonte
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA19107
| | - Sergio L. Menezes-Filho
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA19107
| | - Melanie Paillard
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA19107
| | - György Hajnóczky
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA19107
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11
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Jadiya P, Cohen HM, Kolmetzky DW, Kadam AA, Tomar D, Elrod JW. Neuronal loss of NCLX-dependent mitochondrial calcium efflux mediates age-associated cognitive decline. iScience 2023; 26:106296. [PMID: 36936788 PMCID: PMC10014305 DOI: 10.1016/j.isci.2023.106296] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 12/12/2022] [Accepted: 02/20/2023] [Indexed: 03/05/2023] Open
Abstract
Mitochondrial calcium overload contributes to neurodegenerative disease development and progression. We recently reported that loss of the mitochondrial sodium/calcium exchanger (NCLX), the primary mechanism of mCa2+ efflux, promotes mCa2+ overload, metabolic derangement, redox stress, and cognitive decline in models of Alzheimer's disease (AD). However, whether disrupted mCa2+ signaling contributes to neuronal pathology and cognitive decline independent of pre-existing amyloid or tau pathology remains unknown. Here, we generated mice with neuronal deletion of the mitochondrial sodium/calcium exchanger (NCLX, Slc8b1 gene), and evaluated age-associated changes in cognitive function and neuropathology. Neuronal loss of NCLX resulted in an age-dependent decline in spatial and cued recall memory, moderate amyloid deposition, mild tau pathology, synaptic remodeling, and indications of cell death. These results demonstrate that loss of NCLX-dependent mCa2+ efflux alone is sufficient to induce an Alzheimer's disease-like pathology and highlights the promise of therapies targeting mCa2+ exchange.
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Affiliation(s)
- Pooja Jadiya
- Cardiovascular Research Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
- Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, 27157, USA
| | - Henry M. Cohen
- Cardiovascular Research Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Devin W. Kolmetzky
- Cardiovascular Research Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Ashlesha A. Kadam
- Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, 27157, USA
| | - Dhanendra Tomar
- Cardiovascular Research Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
- Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, 27157, USA
| | - John W. Elrod
- Cardiovascular Research Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
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12
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Sánchez-Aguilera P, López-Crisosto C, Norambuena-Soto I, Penannen C, Zhu J, Bomer N, Hoes MF, Van Der Meer P, Chiong M, Westenbrink BD, Lavandero S. IGF-1 boosts mitochondrial function by a Ca 2+ uptake-dependent mechanism in cultured human and rat cardiomyocytes. Front Physiol 2023; 14:1106662. [PMID: 36846332 PMCID: PMC9944404 DOI: 10.3389/fphys.2023.1106662] [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: 11/24/2022] [Accepted: 01/23/2023] [Indexed: 02/10/2023] Open
Abstract
A physiological increase in cardiac workload results in adaptive cardiac remodeling, characterized by increased oxidative metabolism and improvements in cardiac performance. Insulin-like growth factor-1 (IGF-1) has been identified as a critical regulator of physiological cardiac growth, but its precise role in cardiometabolic adaptations to physiological stress remains unresolved. Mitochondrial calcium (Ca2+) handling has been proposed to be required for sustaining key mitochondrial dehydrogenase activity and energy production during increased workload conditions, thus ensuring the adaptive cardiac response. We hypothesized that IGF-1 enhances mitochondrial energy production through a Ca2+-dependent mechanism to ensure adaptive cardiomyocyte growth. We found that stimulation with IGF-1 resulted in increased mitochondrial Ca2+ uptake in neonatal rat ventricular myocytes and human embryonic stem cell-derived cardiomyocytes, estimated by fluorescence microscopy and indirectly by a reduction in the pyruvate dehydrogenase phosphorylation. We showed that IGF-1 modulated the expression of mitochondrial Ca2+ uniporter (MCU) complex subunits and increased the mitochondrial membrane potential; consistent with higher MCU-mediated Ca2+ transport. Finally, we showed that IGF-1 improved mitochondrial respiration through a mechanism dependent on MCU-mediated Ca2+ transport. In conclusion, IGF-1-induced mitochondrial Ca2+ uptake is required to boost oxidative metabolism during cardiomyocyte adaptive growth.
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Affiliation(s)
- Pablo Sánchez-Aguilera
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Facultad de Medicina, Universidad de Chile, Santiago, Chile,Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Camila López-Crisosto
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Ignacio Norambuena-Soto
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Christian Penannen
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Jumo Zhu
- Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Nils Bomer
- Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Matijn F. Hoes
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, Netherlands,Department of Genetics and Cell Biology, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Netherlands,CARIM School for Cardiovascular Diseases, Maastricht, Netherlands
| | - Peter Van Der Meer
- Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Mario Chiong
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - B. Daan Westenbrink
- Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands,*Correspondence: B. Daan Westenbrink, ; Sergio Lavandero,
| | - Sergio Lavandero
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Facultad de Medicina, Universidad de Chile, Santiago, Chile,Cardiology Division, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States,*Correspondence: B. Daan Westenbrink, ; Sergio Lavandero,
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13
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Lysakowski A, Govindaraju AC, Raphael RM. Structural and Functional Diversity of Mitochondria in Vestibular/Cochlear Hair Cells and Vestibular Calyx Afferents. Hear Res 2022; 426:108612. [DOI: 10.1016/j.heares.2022.108612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 07/21/2022] [Accepted: 09/19/2022] [Indexed: 11/30/2022]
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14
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Liu T, Wang G, Zhang X, Liu X, Liang Z, Ren X, Yan D, Zhang W. B serum proteome profiles revealed dysregulated proteins and mechanisms associated with insomnia patients: A preliminary study. Front Integr Neurosci 2022; 16:936955. [PMID: 35958162 PMCID: PMC9360785 DOI: 10.3389/fnint.2022.936955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 06/30/2022] [Indexed: 11/13/2022] Open
Abstract
Background Insomnia is a clinical problem of significant public health importance; however, the underlying pathogenesis of this disorder is not comprehensively understood. Methods To identify potential treatment targets and unfold one of the gaps that were involved in insomnia pathological mechanisms, we employed a tandem mass tag-based (TMT) quantitative proteomics technology to detect differentially expressed proteins (DEPs) in serum from patients with insomnia and controls. DEPs were further analyzed by bioinformatics platforms. In addition, parallel reaction monitoring (PRM) was used to verify the TMT results. Results Patients with insomnia had poorer sleep quality compared with healthy controls. A total of 106 DEPs were identified among patients with insomnia and controls. They were mainly enriched in immune and inflammation-related biological functions and signaling pathways. Using the protein–protein interaction network, we screened the 10 most connected proteins as key DEPs. We predicted that four key DEPs were subject to targeted regulation by natural compounds of herbs. Eight key DEPs were validated using PRM in an additional 15 patients with insomnia and 15 controls, and the results also supported the experimental findings. Conclusion We identified aberrantly expressed proteins in insomnia that may be involved in the immune-inflammatory response. The 10 key DEPs screened may be potential targets for insomnia, especially FN1, EGF, HP, and IGF1. The results of this study will broaden our understanding of the pathological mechanisms of insomnia and provide more possibilities for pharmacotherapy.
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Affiliation(s)
- Tao Liu
- Traditional Chinese Medicine Hospital Affiliated with Xinjiang Medical University, Ürümqi, China
- Postdoctoral Workstation of Traditional Chinese Medicine Hospital of Xinjiang Uygur Autonomous Region, Ürümqi, China
| | - Guanying Wang
- Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Xingping Zhang
- Traditional Chinese Medicine Hospital Affiliated with Xinjiang Medical University, Ürümqi, China
- College of Traditional Chinese Medicine, Xinjiang Medical University, Ürümqi, China
- *Correspondence: Xingping Zhang,
| | - Xin Liu
- College of Traditional Chinese Medicine, Xinjiang Medical University, Ürümqi, China
| | - Zhengting Liang
- College of Traditional Chinese Medicine, Xinjiang Medical University, Ürümqi, China
| | - Xiaojuan Ren
- Xinjiang Urumqi Traditional Chinese Medicine Hospital, Ürümqi, China
| | - Deqi Yan
- College of Traditional Chinese Medicine, Xinjiang Medical University, Ürümqi, China
| | - Wenhui Zhang
- College of Traditional Chinese Medicine, Xinjiang Medical University, Ürümqi, China
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15
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Jackson J, Wischhof L, Scifo E, Pellizzer A, Wang Y, Piazzesi A, Gentile D, Siddig S, Stork M, Hopkins CE, Händler K, Weis J, Roos A, Schultze JL, Nicotera P, Ehninger D, Bano D. SGPL1 stimulates VPS39 recruitment to the mitochondria in MICU1 deficient cells. Mol Metab 2022; 61:101503. [PMID: 35452878 PMCID: PMC9170783 DOI: 10.1016/j.molmet.2022.101503] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/08/2022] [Accepted: 04/15/2022] [Indexed: 01/21/2023] Open
Abstract
Objective Mitochondrial “retrograde” signaling may stimulate organelle biogenesis as a compensatory adaptation to aberrant activity of the oxidative phosphorylation (OXPHOS) system. To maintain energy-consuming processes in OXPHOS deficient cells, alternative metabolic pathways are functionally coupled to the degradation, recycling and redistribution of biomolecules across distinct intracellular compartments. While transcriptional regulation of mitochondrial network expansion has been the focus of many studies, the molecular mechanisms promoting mitochondrial maintenance in energy-deprived cells remain poorly investigated. Methods We performed transcriptomics, quantitative proteomics and lifespan assays to identify pathways that are mechanistically linked to mitochondrial network expansion and homeostasis in Caenorhabditis elegans lacking the mitochondrial calcium uptake protein 1 (MICU-1/MICU1). To support our findings, we carried out biochemical and image analyses in mammalian cells and mouse-derived tissues. Results We report that micu-1(null) mutations impair the OXPHOS system and promote C. elegans longevity through a transcriptional program that is independent of the mitochondrial calcium uniporter MCU-1/MCU and the essential MCU regulator EMRE-1/EMRE. We identify sphingosine phosphate lyase SPL-1/SGPL1 and the ATFS-1-target HOPS complex subunit VPS-39/VPS39 as critical lifespan modulators of micu-1(null) mutant animals. Cross-species investigation indicates that SGPL1 upregulation stimulates VPS39 recruitment to the mitochondria, thereby enhancing mitochondria-lysosome contacts. Consistently, VPS39 downregulation compromises mitochondrial network maintenance and basal autophagic flux in MICU1 deficient cells. In mouse-derived muscles, we show that VPS39 recruitment to the mitochondria may represent a common signature associated with altered OXPHOS system. Conclusions Our findings reveal a previously unrecognized SGPL1/VPS39 axis that stimulates intracellular organelle interactions and sustains autophagy and mitochondrial homeostasis in OXPHOS deficient cells. micu-1(null) nematodes are long-lived mitochondrial mutants. MICU-1/MICU1 deficiency stimulates VPS-39/VPS39 and SPL-1/SGPL1 upregulation. VPS-39 sustains mitochondrial network expansion in micu-1(null) nematodes. VPS39 and SGPL1 expression influences mitochondria-lysosome contact sites in MICU1 deficient cells. VPS39/SGPL1 signaling may be a common signature of mitochondrial deficient cells.
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Affiliation(s)
- Joshua Jackson
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Lena Wischhof
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Enzo Scifo
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Anna Pellizzer
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Yiru Wang
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Antonia Piazzesi
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Debora Gentile
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Sana Siddig
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Miriam Stork
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | | | - Kristian Händler
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany; PRECISE Platform for Single Cell Genomics and Epigenomics, German Center for Neurodegenerative Diseases (DZNE), University of Bonn, Bonn, Germany
| | - Joachim Weis
- Institute of Neuropathology, RWTH Aachen University Hospital, Aachen, Germany
| | - Andreas Roos
- Universitätsklinikum Essen and Universität Duisburg-Essen, Essen, Germany
| | - Joachim L Schultze
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany; PRECISE Platform for Single Cell Genomics and Epigenomics, German Center for Neurodegenerative Diseases (DZNE), University of Bonn, Bonn, Germany; LIMES Institute, Department for Genomics and Immunoregulation, University of Bonn, Bonn, Germany
| | | | - Dan Ehninger
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Daniele Bano
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.
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16
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Singh R, Bartok A, Paillard M, Tyburski A, Elliott M, Hajnóczky G. Uncontrolled mitochondrial calcium uptake underlies the pathogenesis of neurodegeneration in MICU1-deficient mice and patients. SCIENCE ADVANCES 2022; 8:eabj4716. [PMID: 35302860 PMCID: PMC8932652 DOI: 10.1126/sciadv.abj4716] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 01/26/2022] [Indexed: 06/01/2023]
Abstract
Dysregulation of mitochondrial Ca2+ homeostasis has been linked to neurodegenerative diseases. Mitochondrial Ca2+ uptake is mediated via the calcium uniporter complex that is primarily regulated by MICU1, a Ca2+-sensing gatekeeper. Recently, human patients with MICU1 loss-of-function mutations were diagnosed with neuromuscular and cognitive impairments. While studies in patient-derived cells revealed altered mitochondrial calcium signaling, the neuronal pathogenesis was difficult to study. To fill this void, we created a neuron-specific MICU1-KO mouse model. These animals show progressive, abnormal motor and cognitive phenotypes likely caused by the degeneration of motor neurons in the spinal cord and the cortex. We found increased susceptibility to mitochondrial Ca2+ overload-induced excitotoxic insults and cell death in MICU1-KO neurons and MICU1-deficient patient-derived cells, which can be blunted by inhibiting the mitochondrial permeability transition pore. Thus, our study identifies altered neuronal mitochondrial Ca2+ homeostasis as causative in the clinical symptoms of MICU1-deficient patients and highlights potential therapeutic targets.
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Affiliation(s)
- Raghavendra Singh
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Adam Bartok
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
- Departent of Biochemistry, Semmelweis University, Budapest, Hungary
| | - Melanie Paillard
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Ashley Tyburski
- Department of Neurological Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - Melanie Elliott
- Department of Neurological Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - György Hajnóczky
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
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17
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Gangfuß A, Hentschel A, Rademacher N, Sickmann A, Stüve B, Horvath R, Gross C, Kohlschmidt N, Förster F, Abicht A, Schänzer A, Schara-Schmidt U, Roos A, Della Marina A. Identification of a novel homozygous SCO2 variant in siblings with early-onset axonal Charcot-Marie-Tooth disease. Hum Mutat 2022; 43:477-486. [PMID: 35112411 DOI: 10.1002/humu.24338] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 01/23/2022] [Accepted: 01/30/2022] [Indexed: 11/11/2022]
Abstract
The synthesis of cytochrome c oxidase 2 (SCO2) gene encodes for a mitochondrial located metallochaperone essential for the synthesis of the cytochrome c oxidase (COX) subunit 2. Recessive mutations in SCO2 have been reported in several cases with fatal infantile cardioencephalomyopathy with COX deficiency and in only four cases with axonal neuropathy. Here, we identified a homozygous pathogenic variant (c.361G>C; p.(Gly121Arg)) in SCO2 in two brothers with isolated axonal motor neuropathy. To address pathogenicity of the amino acid substitution, biochemical studies were performed and revealed increased level of the mutant SCO2-protein and a dysregulation of COX subunits in leukocytes and moreover unraveled decrease of proteins involved in the manifestation of neuropathies. Hence, our combined data strengthen the concept of SCO2 being causative for a very rare form of axonal neuropathy, expand its molecular genetic spectrum and provide first biochemical insights into the underlying pathophysiology. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Andrea Gangfuß
- Department of Pediatric Neurology, Centre for Neuromuscular Disorders, Centre for Translational Neuro- and Behavioral Sciences, University Duisburg-Essen, Essen, Germany
| | - Andreas Hentschel
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V, Dortmund, Germany
| | - Nina Rademacher
- Department of Pediatric Neurology, Centre for Neuromuscular Disorders, Centre for Translational Neuro- and Behavioral Sciences, University Duisburg-Essen, Essen, Germany
| | - Albert Sickmann
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V, Dortmund, Germany
| | - Burkhard Stüve
- Department of Pediatric Neurology, Centre for Neuromuscular Disorders, Centre for Translational Neuro- and Behavioral Sciences, University Duisburg-Essen, Essen, Germany
| | - Rita Horvath
- Department of Clinical Neurosciences, John Van Geest Centre for Brain Repair, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Claudia Gross
- Institute of Clinical Genetics and Tumor Genetics, Bonn, Germany
| | | | - Fabian Förster
- Department of Pediatric Neurology, Centre for Neuromuscular Disorders, Centre for Translational Neuro- and Behavioral Sciences, University Duisburg-Essen, Essen, Germany
| | - Angela Abicht
- Department of Neurology, Friedrich-Baur Institute, Munich, Germany.,Medical Genetic Center Munich, Munich, Germany
| | - Anne Schänzer
- Institute of Neuropathology, Justus Liebig University, Giessen, Germany
| | - Ulrike Schara-Schmidt
- Department of Pediatric Neurology, Centre for Neuromuscular Disorders, Centre for Translational Neuro- and Behavioral Sciences, University Duisburg-Essen, Essen, Germany
| | - Andreas Roos
- Department of Pediatric Neurology, Centre for Neuromuscular Disorders, Centre for Translational Neuro- and Behavioral Sciences, University Duisburg-Essen, Essen, Germany.,Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada
| | - Adela Della Marina
- Department of Pediatric Neurology, Centre for Neuromuscular Disorders, Centre for Translational Neuro- and Behavioral Sciences, University Duisburg-Essen, Essen, Germany
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