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Guo J, Wang Y, Shi C, Zhang D, Zhang Q, Wang L, Gong Z. Mitochondrial calcium uniporter complex: Unveiling the interplay between its regulators and calcium homeostasis. Cell Signal 2024; 121:111284. [PMID: 38964444 DOI: 10.1016/j.cellsig.2024.111284] [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: 04/27/2024] [Revised: 06/28/2024] [Accepted: 07/01/2024] [Indexed: 07/06/2024]
Abstract
The mitochondrial calcium uniporter complex (MCUc), serving as the specific channel for calcium influx into the mitochondrial matrix, is integral to calcium homeostasis and cellular integrity. Given its importance, ongoing research spans various disease models to understand the properties of the MCUc in pathophysiological contexts, but reported a different conclusion. Therefore, this review delves into the profound connection between MCUc-mediated calcium transients and cellular signaling pathways, mitochondrial dynamics, metabolism, and cell death. Additionally, we shed light on the recent advancements concerning the structural intricacies and auxiliary components of the MCUc in both resting and activated states. Furthermore, emphasis is placed on novel extrinsic and intrinsic regulators of the MCUc and their therapeutic implications across a spectrum of diseases. Meanwhile, we employed molecular docking simulations and identified candidate traditional Chinese medicine components with potential binding sites to the MCUc, potentially offering insights for further research on MCUc modulation.
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Affiliation(s)
- Jin Guo
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China
| | - Yukun Wang
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China
| | - Chunxia Shi
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China
| | - Danmei Zhang
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China
| | - Qingqi Zhang
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China
| | - Luwen Wang
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China
| | - Zuojiong Gong
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan, China.
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2
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Godoy JA, Mira RG, Inestrosa NC. Intracellular effects of lithium in aging neurons. Ageing Res Rev 2024; 99:102396. [PMID: 38942199 DOI: 10.1016/j.arr.2024.102396] [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: 04/15/2024] [Revised: 06/14/2024] [Accepted: 06/25/2024] [Indexed: 06/30/2024]
Abstract
Lithium therapy received approval during the 1970s, and it has been used for its antidepressant, antimanic, and anti-suicidal effects for acute and long-term prophylaxis and treatment of bipolar disorder (BPD). These properties have been well established; however, the molecular and cellular mechanisms remain controversial. In the past few years, many studies demonstrated that at the cellular level, lithium acts as a regulator of neurogenesis, aging, and Ca2+ homeostasis. At the molecular level, lithium modulates aging by inhibiting glycogen synthase kinase-3β (GSK-3β), and the phosphatidylinositol (PI) cycle; latter, lithium specifically inhibits inositol production, acting as a non-competitive inhibitor of inositol monophosphatase (IMPase). Mitochondria and peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) have been related to lithium activity, and its regulation is mediated by GSK-3β degradation and inhibition. Lithium also impacts Ca2+ homeostasis in the mitochondria modulating the function of the lithium-permeable mitochondrial Na+-Ca2+exchanger (NCLX), affecting Ca2+ efflux from the mitochondrial matrix to the endoplasmic reticulum (ER). A close relationship between the protease Omi, GSK-3β, and PGC-1α has also been established. The purpose of this review is to summarize some of the intracellular mechanisms related to lithium activity and how, through them, neuronal aging could be controlled.
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Affiliation(s)
- Juan A Godoy
- Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Rodrigo G Mira
- Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Escuela de Medicina, Universidad de Magallanes, Punta Arenas, Chile
| | - Nibaldo C Inestrosa
- Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Escuela de Medicina, Universidad de Magallanes, Punta Arenas, Chile; Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.
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3
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Amjid U, Aziz U, Habib U, Jabeen I. Biological regulatory network analysis for targeting the mitochondrial calcium uniporter (MCU) mediated calcium (Ca 2+) transport in neurodegenerative disorders. Cell Biochem Funct 2024; 42:e4082. [PMID: 38944766 DOI: 10.1002/cbf.4082] [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: 04/02/2024] [Revised: 05/30/2024] [Accepted: 06/18/2024] [Indexed: 07/01/2024]
Abstract
Calcium (Ca2+) has been observed as the most important ion involved in a series of cellular processes and its homeostasis is critical for normal cellular functions. Mitochondrial calcium uniporter (MCU) complex has been recognized as the most important calcium-specific channel located in the inner mitochondrial membrane and is one of the major players in maintaining the Ca2+ homeostasis by transporting Ca2+ across the mitochondrial membrane. Furthermore, dysregulation of the mitochondrial Ca2+ homeostasis has been orchestrated to neurodegenerative response. This necessitates quantitative evaluation of the MCU-dependent mROS production and subsequent cellular responses for more specific therapeutic interventions against neurodegenerative disorders. Towards this goal, here we present a biological regulatory network of MCU to dynamically simulate the MCU-mediated ROS production and its response in neurodegeneration. Previously, ruthenium complex RuRed and its derivatives have been reported to show low nM to high µM potency against MCU to maintain cytosolic Ca2+ (cCa2+) homeostasis by modulating mitochondrial Ca2+ (mCa2+) uptake. Therefore, structural modeling and dynamic simulation of MCU pore-forming subunit is performed to probe the interaction profiling of previously reported Ru265 and its derivatives compounds with MCU. The current study highlighted MCU as a potential drug target in neurodegenerative disorders. Furthermore, ASP261 and GLU264 amino acid residues in DIME motif of MCU pore-forming subunits are identified as crucial for modulating the activity of MCU in neurodegenerative disorders.
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Affiliation(s)
- Umar Amjid
- School of Interdisciplinary Engineering & Sciences (SINES), National University of Sciences & Technology (NUST), Islamabad, Pakistan
- Department of Paediatrics and Child Health, Medical College, Aga Khan University Hospital, Karachi, Pakistan
| | - Ubair Aziz
- School of Interdisciplinary Engineering & Sciences (SINES), National University of Sciences & Technology (NUST), Islamabad, Pakistan
| | - Uzma Habib
- School of Interdisciplinary Engineering & Sciences (SINES), National University of Sciences & Technology (NUST), Islamabad, Pakistan
| | - Ishrat Jabeen
- School of Interdisciplinary Engineering & Sciences (SINES), National University of Sciences & Technology (NUST), Islamabad, Pakistan
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4
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Azevedo RDSD, Falcão KVG, Almeida SMVD, Araújo MC, Silva-Filho RC, Souza Maia MBD, Amaral IPGD, Leite ACR, de Souza Bezerra R. The tissue-specific nature of physiological zebrafish mitochondrial bioenergetics. Mitochondrion 2024; 77:101901. [PMID: 38777222 DOI: 10.1016/j.mito.2024.101901] [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: 06/02/2023] [Revised: 04/27/2024] [Accepted: 05/15/2024] [Indexed: 05/25/2024]
Abstract
Zebrafish are a powerful tool to study a myriad of experimental conditions, including mitochondrial bioenergetics. Considering that mitochondria are different in many aspects depending on the tissue evaluated, in the zebrafish model there is still a lack of this investigation. Especially for juvenile zebrafish. In the present study, we examined whether different tissues from zebrafish juveniles show mitochondrial density- and tissue-specificity comparing brain, liver, heart, and skeletal muscle (SM). The liver and brain complex IV showed the highest O2 consumption of all ETC in all tissues (10x when compared to other respiratory complexes). The liver showed a higher potential for ROS generation. In this way, the brain and liver showed more susceptibility to O2- generation when compared to other tissues. Regarding Ca2+ transport, the brain showed greater capacity for Ca2+ uptake and the liver presented low Ca2+ uptake capacity. The liver and brain were more susceptible to producing NO. The enzymes SOD and Catalase showed high activity in the brain, whereas GPx showed higher activity in the liver and CS in the SM. TEM reveals, as expected, a physiological diverse mitochondrial morphology. The essential differences between zebrafish tissues investigated probably reflect how the mitochondria play a diverse role in systemic homeostasis. This feature may not be limited to normal metabolic functions but also to stress conditions. In summary, mitochondrial bioenergetics in zebrafish juvenile permeabilized tissues showed a tissue-specificity and a useful tool to investigate conditions of redox system imbalance, mainly in the liver and brain.
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Affiliation(s)
- Rafael David Souto de Azevedo
- Laboratório de Biologia Celular e Molecular, Universidade de Pernambuco - UPE, Campus Garanhuns, Garanhuns, PE, Brazil.
| | - Kivia Vanessa Gomes Falcão
- Departamento de Bioquímica, Universidade Federal de Pernambuco, Cidade Universitária, Recife, PE, Brazil
| | | | - Marlyete Chagas Araújo
- Departamento de Bioquímica, Universidade Federal de Pernambuco, Cidade Universitária, Recife, PE, Brazil
| | | | | | | | | | - Ranilson de Souza Bezerra
- Departamento de Bioquímica, Universidade Federal de Pernambuco, Cidade Universitária, Recife, PE, Brazil
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5
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Vecellio Reane D, Serna JDC, Raffaello A. Unravelling the complexity of the mitochondrial Ca 2+ uniporter: regulation, tissue specificity, and physiological implications. Cell Calcium 2024; 121:102907. [PMID: 38788256 DOI: 10.1016/j.ceca.2024.102907] [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: 04/23/2024] [Revised: 05/10/2024] [Accepted: 05/13/2024] [Indexed: 05/26/2024]
Abstract
Calcium (Ca2+) signalling acts a pleiotropic message within the cell that is decoded by the mitochondria through a sophisticated ion channel known as the Mitochondrial Ca2+ Uniporter (MCU) complex. Under physiological conditions, mitochondrial Ca2+ signalling is crucial for coordinating cell activation with energy production. Conversely, in pathological scenarios, it can determine the fine balance between cell survival and death. Over the last decade, significant progress has been made in understanding the molecular bases of mitochondrial Ca2+ signalling. This began with the elucidation of the MCU channel components and extended to the elucidation of the mechanisms that regulate its activity. Additionally, increasing evidence suggests molecular mechanisms allowing tissue-specific modulation of the MCU complex, tailoring channel activity to the specific needs of different tissues or cell types. This review aims to explore the latest evidence elucidating the regulation of the MCU complex, the molecular factors controlling the tissue-specific properties of the channel, and the physiological and pathological implications of mitochondrial Ca2+ signalling in different tissues.
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Affiliation(s)
- Denis Vecellio Reane
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center (HDC), Helmholtz Zentrum Munich, Germany.
| | - Julian D C Serna
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Anna Raffaello
- Department of Biomedical Sciences, University of Padova, Italy.
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6
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Colussi DM, Stathopulos PB. The mitochondrial calcium uniporter: Balancing tumourigenic and anti-tumourigenic responses. J Physiol 2024; 602:3315-3339. [PMID: 38857425 DOI: 10.1113/jp285515] [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: 12/26/2023] [Accepted: 05/20/2024] [Indexed: 06/12/2024] Open
Abstract
Increased malignancy and poor treatability associated with solid tumour cancers have commonly been attributed to mitochondrial calcium (Ca2+) dysregulation. The mitochondrial Ca2+ uniporter complex (mtCU) is the predominant mode of Ca2+ uptake into the mitochondrial matrix. The main components of mtCU are the pore-forming mitochondrial Ca2+ uniporter (MCU) subunit, MCU dominant-negative beta (MCUb) subunit, essential MCU regulator (EMRE) and the gatekeeping mitochondrial Ca2+ uptake 1 and 2 (MICU1 and MICU2) proteins. In this review, we describe mtCU-mediated mitochondrial Ca2+ dysregulation in solid tumour cancer types, finding enhanced mtCU activity observed in colorectal cancer, breast cancer, oral squamous cell carcinoma, pancreatic cancer, hepatocellular carcinoma and embryonal rhabdomyosarcoma. By contrast, decreased mtCU activity is associated with melanoma, whereas the nature of mtCU dysregulation remains unclear in glioblastoma. Furthermore, we show that numerous polymorphisms associated with cancer may alter phosphorylation sites on the pore forming MCU and MCUb subunits, which cluster at interfaces with EMRE. We highlight downstream/upstream biomolecular modulators of MCU and MCUb that alter mtCU-mediated mitochondrial Ca2+ uptake and may be used as biomarkers or to aid in the development of novel cancer therapeutics. Additionally, we provide an overview of the current small molecule inhibitors of mtCU that interact with the Asp residue of the critical Asp-Ile-Met-Glu motif or through other allosteric regulatory mechanisms to block Ca2+ permeation. Finally, we describe the relationship between MCU- and MCUb-mediating microRNAs and mitochondrial Ca2+ uptake that should be considered in the discovery of new treatment approaches for cancer.
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Affiliation(s)
- Danielle M Colussi
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada
| | - Peter B Stathopulos
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada
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Roman B, Mastoor Y, Sun J, Villanueva HC, Hinojosa G, Springer D, Liu JC, Murphy E. MICU3 Regulates Mitochondrial Calcium and Cardiac Hypertrophy. Circ Res 2024; 135:26-40. [PMID: 38747181 PMCID: PMC11189743 DOI: 10.1161/circresaha.123.324026] [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: 11/21/2023] [Accepted: 05/01/2024] [Indexed: 06/22/2024]
Abstract
BACKGROUND Calcium (Ca2+) uptake by mitochondria occurs via the mitochondrial Ca2+ uniporter. Mitochondrial Ca2+ uniporter exists as a complex, regulated by 3 MICU (mitochondrial Ca2+ uptake) proteins localized in the intermembrane space: MICU1, MICU2, and MICU3. Although MICU3 is present in the heart, its role is largely unknown. METHODS We used CRISPR-Cas9 to generate a mouse with global deletion of MICU3 and an adeno-associated virus (AAV9) to overexpress MICU3 in wild-type mice. We examined the role of MICU3 in regulating mitochondrial calcium ([Ca2+]m) in ex vivo hearts using an optical method following adrenergic stimulation in perfused hearts loaded with a Ca2+-sensitive fluorophore. Additionally, we studied how deletion and overexpression of MICU3, respectively, impact cardiac function in vivo by echocardiography and the molecular composition of the mitochondrial Ca2+ uniporter complex via Western blot, immunoprecipitation, and Blue native-PAGE analysis. Finally, we measured MICU3 expression in failing human hearts. RESULTS MICU3 knock out hearts and cardiomyocytes exhibited a significantly smaller increase in [Ca2+]m than wild-type hearts following acute isoproterenol infusion. In contrast, heart with overexpression of MICU3 exhibited an enhanced increase in [Ca2+]m compared with control hearts. Echocardiography analysis showed no significant difference in cardiac function in knock out MICU3 mice relative to wild-type mice at baseline. However, mice with overexpression of MICU3 exhibited significantly reduced ejection fraction and fractional shortening compared with control mice. We observed a significant increase in the ratio of heart weight to tibia length in hearts with overexpression of MICU3 compared with controls, consistent with hypertrophy. We also found a significant decrease in MICU3 protein and expression in failing human hearts. CONCLUSIONS Our results indicate that increased and decreased expression of MICU3 enhances and reduces, respectively, the uptake of [Ca2+]m in the heart. We conclude that MICU3 plays an important role in regulating [Ca2+]m physiologically, and overexpression of MICU3 is sufficient to induce cardiac hypertrophy, making MICU3 a possible therapeutic target.
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Affiliation(s)
- Barbara Roman
- Cardiac Physiology Lab NHLBI, NIH, Bethesda, Maryland
| | - Yusuf Mastoor
- Cardiac Physiology Lab NHLBI, NIH, Bethesda, Maryland
| | - Junhui Sun
- Cardiac Physiology Lab NHLBI, NIH, Bethesda, Maryland
| | - Hector Chapoy Villanueva
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, MN
| | | | | | - Julia C. Liu
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, MN
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Xu P, Swain S, Novorolsky RJ, Garcia E, Huang Z, Snutch TP, Wilson JJ, Robertson GS, Renden RB. The mitochondrial calcium uniporter inhibitor Ru265 increases neuronal excitability and reduces neurotransmission via off-target effects. Br J Pharmacol 2024. [PMID: 38779706 DOI: 10.1111/bph.16425] [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: 09/25/2023] [Revised: 04/24/2024] [Accepted: 04/25/2024] [Indexed: 05/25/2024] Open
Abstract
BACKGROUND AND PURPOSE Excitotoxicity due to mitochondrial calcium (Ca2+) overloading can trigger neuronal cell death in a variety of pathologies. Inhibiting the mitochondrial calcium uniporter (MCU) has been proposed as a therapeutic avenue to prevent calcium overloading. Ru265 (ClRu(NH3)4(μ-N)Ru(NH3)4Cl]Cl3) is a cell-permeable inhibitor of the mitochondrial calcium uniporter (MCU) with nanomolar affinity. Ru265 reduces sensorimotor deficits and neuronal death in models of ischemic stroke. However, the therapeutic use of Ru265 is limited by the induction of seizure-like behaviours. EXPERIMENTAL APPROACH We examined the effect of Ru265 on synaptic and neuronal function in acute brain slices and hippocampal neuron cultures derived from mice, in control and where MCU expression was genetically abrogated. KEY RESULTS Ru265 decreased evoked responses from calyx terminals and induced spontaneous action potential firing of both the terminal and postsynaptic principal cell. Recordings of presynaptic Ca2+ currents suggested that Ru265 blocks the P/Q type channel, confirmed by the inhibition of currents in cells exogenously expressing the P/Q type channel. Measurements of presynaptic K+ currents further revealed that Ru265 blocked a KCNQ current, leading to increased membrane excitability, underlying spontaneous spiking. Ca2+ imaging of hippocampal neurons showed that Ru265 increased synchronized, high-amplitude events, recapitulating seizure-like activity seen in vivo. Importantly, MCU ablation did not suppress Ru265-induced increases in neuronal activity and seizures. CONCLUSIONS AND IMPLICATIONS Our findings provide a mechanistic explanation for the pro-convulsant effects of Ru265 and suggest counter screening assays based on the measurement of P/Q and KCNQ channel currents to identify safe MCU inhibitors.
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Affiliation(s)
- Peng Xu
- Department of Physiology and Cell Biology, University of Nevada, Reno, Reno, Nevada, USA
| | - Sarpras Swain
- Department of Physiology and Cell Biology, University of Nevada, Reno, Reno, Nevada, USA
| | - Robyn J Novorolsky
- Department of Pharmacology, Dalhousie University, Halifax, Nova Scotia, Canada
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Esperanza Garcia
- Michael Smith Laboratories and Djavad Mowafaghian Centre for Brain Health University of British Columbia, Vancouver, British Columbia, Canada
| | - Zhouyang Huang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA
| | - Terrance P Snutch
- Michael Smith Laboratories and Djavad Mowafaghian Centre for Brain Health University of British Columbia, Vancouver, British Columbia, Canada
| | - Justin J Wilson
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA
| | - George S Robertson
- Department of Pharmacology, Dalhousie University, Halifax, Nova Scotia, Canada
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Robert B Renden
- Department of Physiology and Cell Biology, University of Nevada, Reno, Reno, Nevada, USA
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Noble M, Colussi DM, Junop M, Stathopulos PB. The MCU and MCUb amino-terminal domains tightly interact: mechanisms for low conductance assembly of the mitochondrial calcium uniporter complex. iScience 2024; 27:109699. [PMID: 38706857 PMCID: PMC11068563 DOI: 10.1016/j.isci.2024.109699] [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: 08/28/2023] [Revised: 02/12/2024] [Accepted: 04/05/2024] [Indexed: 05/07/2024] Open
Abstract
The mitochondrial calcium (Ca2+) uniporter (MCU) complex is regulated via integration of the MCU dominant negative beta subunit (MCUb), a low conductance paralog of the main MCU pore forming protein. The MCU amino (N)-terminal domain (NTD) also modulates channel function through cation binding to the MCU regulating acidic patch (MRAP). MCU and MCUb have high sequence similarities, yet the structural and functional roles of MCUb-NTD remain unknown. Here, we report that MCUb-NTD exhibits α-helix/β-sheet structure with a high thermal stability, dependent on protein concentration. Remarkably, MCU- and MCUb-NTDs heteromerically interact with ∼nM affinity, increasing secondary structure and stability and structurally perturbing MRAP. Further, we demonstrate MCU and MCUb co-localization is suppressed upon NTD deletion concomitant with increased mitochondrial Ca2+ uptake. Collectively, our data show that MCU:MCUb NTD tight interactions are promoted by enhanced regular structure and stability, augmenting MCU:MCUb co-localization, lowering mitochondrial Ca2+ uptake and implicating an MRAP-sensing mechanism.
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Affiliation(s)
- Megan Noble
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A5C1, Canada
| | - Danielle M. Colussi
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A5C1, Canada
| | - Murray Junop
- Department of Biochemistry, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A5C1, Canada
| | - Peter B. Stathopulos
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A5C1, Canada
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10
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Wang J, Jiang J, Hu H, Chen L. MCU complex: Exploring emerging targets and mechanisms of mitochondrial physiology and pathology. J Adv Res 2024:S2090-1232(24)00075-4. [PMID: 38417574 DOI: 10.1016/j.jare.2024.02.013] [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: 11/16/2023] [Revised: 02/16/2024] [Accepted: 02/17/2024] [Indexed: 03/01/2024] Open
Abstract
BACKGROUND Globally, the onset and progression of multiple human diseases are associated with mitochondrial dysfunction and dysregulation of Ca2+ uptake dynamics mediated by the mitochondrial calcium uniporter (MCU) complex, which plays a key role in mitochondrial dysfunction. Despite relevant studies, the underlying pathophysiological mechanisms have not yet been fully elucidated. AIM OF REVIEW This article provides an in-depth analysis of the current research status of the MCU complex, focusing on its molecular composition, regulatory mechanisms, and association with diseases. In addition, we conducted an in-depth analysis of the regulatory effects of agonists, inhibitors, and traditional Chinese medicine (TCM) monomers on the MCU complex and their application prospects in disease treatment. From the perspective of medicinal chemistry, we conducted an in-depth analysis of the structure-activity relationship between these small molecules and MCU and deduced potential pharmacophores and binding pockets. Simultaneously, key structural domains of the MCU complex in Homo sapiens were identified. We also studied the functional expression of the MCU complex in Drosophila, Zebrafish, and Caenorhabditis elegans. These analyses provide a basis for exploring potential treatment strategies targeting the MCU complex and provide strong support for the development of future precision medicine and treatments. KEY SCIENTIFIC CONCEPTS OF REVIEW The MCU complex exhibits varying behavior across different tissues and plays various roles in metabolic functions. It consists of six MCU subunits, an essential MCU regulator (EMRE), and solute carrier 25A23 (SLC25A23). They regulate processes, such as mitochondrial Ca2+ (mCa2+) uptake, mitochondrial adenosine triphosphate (ATP) production, calcium dynamics, oxidative stress (OS), and cell death. Regulation makes it a potential target for treating diseases, especially cardiovascular diseases, neurodegenerative diseases, inflammatory diseases, metabolic diseases, and tumors.
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Affiliation(s)
- Jin Wang
- Institute of Pharmacy and Pharmacology, Learning Key Laboratory for Pharmacoproteomics, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, School of Pharmaceutical Science, Hengyang Medical College, University of South China, Hengyang 421001, China
| | - Jinyong Jiang
- Department of Pharmacy, The First Affiliated Hospital of Jishou University, Jishou 416000, China
| | - Haoliang Hu
- Institute of Pharmacy and Pharmacology, Learning Key Laboratory for Pharmacoproteomics, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, School of Pharmaceutical Science, Hengyang Medical College, University of South China, Hengyang 421001, China; College of Medicine, Hunan University of Arts and Science, Changde 415000, China.
| | - Linxi Chen
- Institute of Pharmacy and Pharmacology, Learning Key Laboratory for Pharmacoproteomics, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, School of Pharmaceutical Science, Hengyang Medical College, University of South China, Hengyang 421001, China.
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11
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Roman B, Mastoor Y, Zhang Y, Gross D, Springer D, Liu C, Glancy B, Murphy E. Loss of mitochondrial Ca 2+ uptake protein 3 impairs skeletal muscle calcium handling and exercise capacity. J Physiol 2024; 602:113-128. [PMID: 38018177 PMCID: PMC10824360 DOI: 10.1113/jp284894] [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: 04/14/2023] [Accepted: 11/06/2023] [Indexed: 11/30/2023] Open
Abstract
Mitochondrial calcium concentration ([Ca2+ ]m ) plays an essential role in bioenergetics, and loss of [Ca2+ ]m homeostasis can trigger diseases and cell death in numerous cell types. Ca2+ uptake into mitochondria occurs via the mitochondrial Ca2+ uniporter (MCU), which is regulated by three mitochondrial Ca2+ uptake (MICU) proteins localized in the intermembrane space, MICU1, 2, and 3. We generated a mouse model of systemic MICU3 ablation and examined its physiological role in skeletal muscle. We found that loss of MICU3 led to impaired exercise capacity. When the muscles were directly stimulated there was a decrease in time to fatigue. MICU3 ablation significantly increased the maximal force of the KO muscle and altered fibre type composition with an increase in the ratio of type IIb (low oxidative capacity) to type IIa (high oxidative capacity) fibres. Furthermore, MICU3-KO mitochondria have reduced uptake of Ca2+ and increased phosphorylation of pyruvate dehydrogenase, indicating that KO animals contain less Ca2+ in their mitochondria. Skeletal muscle from MICU3-KO mice exhibited lower net oxidation of NADH during electrically stimulated muscle contraction compared with wild-type. These data demonstrate that MICU3 plays a role in skeletal muscle physiology by setting the proper threshold for mitochondrial Ca2+ uptake, which is important for matching energy demand and supply in muscle. KEY POINTS: Mitochondrial calcium uptake is an important regulator of bioenergetics and cell death and is regulated by the mitochondrial calcium uniporter (MCU) and three calcium sensitive regulatory proteins (MICU1, 2 and 3). Loss of MICU3 leads to impaired exercise capacity and decreased time to skeletal muscle fatigue. Skeletal muscle from MICU3-KO mice exhibits a net oxidation of NADH during electrically stimulated muscle contractions, suggesting that MICU3 plays a role in skeletal muscle physiology by matching energy demand and supply.
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Affiliation(s)
| | | | - Yingfan Zhang
- Muscle Energetics, NHLBI, and NIAMS, NIH, Bethesda, MD, USA
| | - Dennis Gross
- Cardiac Physiology, NHLBI, NIH, Bethesda, MD, USA
| | | | - Chengyu Liu
- Transgenic Core, NHLBI, NIH, Bethesda, MD, USA
| | - Brian Glancy
- Muscle Energetics, NHLBI, and NIAMS, NIH, Bethesda, MD, USA
- Transgenic Core, NHLBI, NIH, Bethesda, MD, USA
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12
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D’Angelo D, Vecellio Reane D, Raffaello A. Neither too much nor too little: mitochondrial calcium concentration as a balance between physiological and pathological conditions. Front Mol Biosci 2023; 10:1336416. [PMID: 38148906 PMCID: PMC10749936 DOI: 10.3389/fmolb.2023.1336416] [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: 11/10/2023] [Accepted: 12/04/2023] [Indexed: 12/28/2023] Open
Abstract
Ca2+ ions serve as pleiotropic second messengers in the cell, regulating several cellular processes. Mitochondria play a fundamental role in Ca2+ homeostasis since mitochondrial Ca2+ (mitCa2+) is a key regulator of oxidative metabolism and cell death. MitCa2+ uptake is mediated by the mitochondrial Ca2+ uniporter complex (MCUc) localized in the inner mitochondrial membrane (IMM). MitCa2+ uptake stimulates the activity of three key enzymes of the Krebs cycle, thereby modulating ATP production and promoting oxidative metabolism. As Paracelsus stated, "Dosis sola facit venenum,"in pathological conditions, mitCa2+ overload triggers the opening of the mitochondrial permeability transition pore (mPTP), enabling the release of apoptotic factors and ultimately leading to cell death. Excessive mitCa2+ accumulation is also associated with a pathological increase of reactive oxygen species (ROS). In this article, we review the precise regulation and the effectors of mitCa2+ in physiopathological processes.
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Affiliation(s)
- Donato D’Angelo
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Denis Vecellio Reane
- Department of Biomedical Sciences, University of Padua, Padua, Italy
- Institute for Diabetes and Obesity, Helmholtz Zentrum München, Munich, Germany
| | - Anna Raffaello
- Department of Biomedical Sciences, Myology Center (CIR-Myo), University of Padua, Padua, Italy
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13
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Alshial EE, Abdulghaney MI, Wadan AHS, Abdellatif MA, Ramadan NE, Suleiman AM, Waheed N, Abdellatif M, Mohammed HS. Mitochondrial dysfunction and neurological disorders: A narrative review and treatment overview. Life Sci 2023; 334:122257. [PMID: 37949207 DOI: 10.1016/j.lfs.2023.122257] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 10/27/2023] [Accepted: 11/07/2023] [Indexed: 11/12/2023]
Abstract
Mitochondria play a vital role in the nervous system, as they are responsible for generating energy in the form of ATP and regulating cellular processes such as calcium (Ca2+) signaling and apoptosis. However, mitochondrial dysfunction can lead to oxidative stress (OS), inflammation, and cell death, which have been implicated in the pathogenesis of various neurological disorders. In this article, we review the main functions of mitochondria in the nervous system and explore the mechanisms related to mitochondrial dysfunction. We discuss the role of mitochondrial dysfunction in the development and progression of some neurological disorders including Parkinson's disease (PD), multiple sclerosis (MS), Alzheimer's disease (AD), depression, and epilepsy. Finally, we provide an overview of various current treatment strategies that target mitochondrial dysfunction, including pharmacological treatments, phototherapy, gene therapy, and mitotherapy. This review emphasizes the importance of understanding the role of mitochondria in the nervous system and highlights the potential for mitochondrial-targeted therapies in the treatment of neurological disorders. Furthermore, it highlights some limitations and challenges encountered by the current therapeutic strategies and puts them in future perspective.
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Affiliation(s)
- Eman E Alshial
- Biochemistry Department, Faculty of Science, Damanhour University, Al Buhayrah, Egypt
| | | | - Al-Hassan Soliman Wadan
- Department of Oral Biology, Faculty of Dentistry, Sinai University, Arish, North Sinai, Egypt
| | | | - Nada E Ramadan
- Department of Biotechnology, Faculty of Science, Tanta University, Gharbia, Egypt
| | | | - Nahla Waheed
- Biochemistry Department, Faculty of Science, Mansoura University, Egypt
| | | | - Haitham S Mohammed
- Biophysics Department, Faculty of Science, Cairo University, Giza, Egypt.
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14
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Pain P, Spinelli F, Gherardi G. Mitochondrial Cation Signalling in the Control of Inflammatory Processes. Int J Mol Sci 2023; 24:16724. [PMID: 38069047 PMCID: PMC10706693 DOI: 10.3390/ijms242316724] [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: 10/23/2023] [Revised: 11/17/2023] [Accepted: 11/17/2023] [Indexed: 12/18/2023] Open
Abstract
Mitochondria are the bioenergetic organelles responsible for the maintenance of cellular homeostasis and have also been found to be associated with inflammation. They are necessary to induce and maintain innate and adaptive immune cell responses, acting as signalling platforms and mediators in effector responses. These organelles are also known to play a pivotal role in cation homeostasis as well, which regulates the inflammatory responses through the modulation of these cation channels. In particular, this review focuses on mitochondrial Ca2+ and K+ fluxes in the regulation of inflammatory response. Nevertheless, this review aims to understand the interplay of these inflammation inducers and pathophysiological conditions. In detail, we discuss some examples of chronic inflammation such as lung, bowel, and metabolic inflammatory diseases caused by a persistent activation of the innate immune response due to a dysregulation of mitochondrial cation homeostasis.
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Affiliation(s)
| | | | - Gaia Gherardi
- Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy; (P.P.); (F.S.)
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15
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Vardar Acar N, Özgül RK. A big picture of the mitochondria-mediated signals: From mitochondria to organism. Biochem Biophys Res Commun 2023; 678:45-61. [PMID: 37619311 DOI: 10.1016/j.bbrc.2023.08.032] [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: 06/06/2023] [Revised: 08/02/2023] [Accepted: 08/16/2023] [Indexed: 08/26/2023]
Abstract
Mitochondria, well-known for years as the powerhouse and biosynthetic center of the cell, are dynamic signaling organelles beyond their energy production and biosynthesis functions. The metabolic functions of mitochondria, playing an important role in various biological events both in physiological and stress conditions, transform them into important cellular stress sensors. Mitochondria constantly communicate with the rest of the cell and even from other cells to the organism, transmitting stress signals including oxidative and reductive stress or adaptive signals such as mitohormesis. Mitochondrial signal transduction has a vital function in regulating integrity of human genome, organelles, cells, and ultimately organism.
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Affiliation(s)
- Neşe Vardar Acar
- Department of Pediatric Metabolism, Institute of Child Health, Faculty of Medicine, Hacettepe University, Ankara, Turkey
| | - R Köksal Özgül
- Department of Pediatric Metabolism, Institute of Child Health, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
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16
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Johnson GA, Krishnamoorthy RR, Stankowska DL. Modulating mitochondrial calcium channels (TRPM2/MCU/NCX) as a therapeutic strategy for neurodegenerative disorders. Front Neurosci 2023; 17:1202167. [PMID: 37928737 PMCID: PMC10622973 DOI: 10.3389/fnins.2023.1202167] [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: 04/07/2023] [Accepted: 10/03/2023] [Indexed: 11/07/2023] Open
Abstract
Efficient cellular communication is essential for the brain to regulate diverse functions like muscle contractions, memory formation and recall, decision-making, and task execution. This communication is facilitated by rapid signaling through electrical and chemical messengers, including voltage-gated ion channels and neurotransmitters. These messengers elicit broad responses by propagating action potentials and mediating synaptic transmission. Calcium influx and efflux are essential for releasing neurotransmitters and regulating synaptic transmission. Mitochondria, which are involved in oxidative phosphorylation, and the energy generation process, also interact with the endoplasmic reticulum to store and regulate cytoplasmic calcium levels. The number, morphology, and distribution of mitochondria in different cell types vary based on energy demands. Mitochondrial damage can cause excess reactive oxygen species (ROS) generation. Mitophagy is a selective process that targets and degrades damaged mitochondria via autophagosome-lysosome fusion. Defects in mitophagy can lead to a buildup of ROS and cell death. Numerous studies have attempted to characterize the relationship between mitochondrial dysfunction and calcium dysregulation in neurodegenerative diseases such as Alzheimer's Disease, Parkinson's Disease, Huntington's Disease, Amyotrophic lateral sclerosis, spinocerebellar ataxia, and aging. Interventional strategies to reduce mitochondrial damage and accumulation could serve as a therapeutic target, but further research is needed to unravel this potential. This review offers an overview of calcium signaling related to mitochondria in various neuronal cells. It critically examines recent findings, exploring the potential roles that mitochondrial dysfunction might play in multiple neurodegenerative diseases and aging. Furthermore, the review identifies existing gaps in knowledge to guide the direction of future research.
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Affiliation(s)
- Gretchen A. Johnson
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, United States
- Department of Microbiology, Immunology and Genetics, School of Biomedical Sciences, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Raghu R. Krishnamoorthy
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, United States
- Department of Pharmacology and Neuroscience, School of Biomedical Sciences, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Dorota L. Stankowska
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, United States
- Department of Microbiology, Immunology and Genetics, School of Biomedical Sciences, University of North Texas Health Science Center, Fort Worth, TX, United States
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17
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Ramezani M, Wagenknecht-Wiesner A, Wang T, Holowka DA, Eliezer D, Baird BA. Alpha synuclein modulates mitochondrial Ca 2+ uptake from ER during cell stimulation and under stress conditions. NPJ Parkinsons Dis 2023; 9:137. [PMID: 37741841 PMCID: PMC10518018 DOI: 10.1038/s41531-023-00578-x] [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: 04/18/2023] [Accepted: 09/08/2023] [Indexed: 09/25/2023] Open
Abstract
Alpha synuclein (a-syn) is an intrinsically disordered protein prevalent in neurons, and aggregated forms are associated with synucleinopathies including Parkinson's disease (PD). Despite the biomedical importance and extensive studies, the physiological role of a-syn and its participation in etiology of PD remain uncertain. We showed previously in model RBL cells that a-syn colocalizes with mitochondrial membranes, depending on formation of N-terminal helices and increasing with mitochondrial stress1. We have now characterized this colocalization and functional correlates in RBL, HEK293, and N2a cells. We find that expression of a-syn enhances stimulated mitochondrial uptake of Ca2+ from the ER, depending on formation of its N-terminal helices but not on its disordered C-terminal tail. Our results are consistent with a-syn acting as a tether between mitochondria and ER, and we show increased contacts between these two organelles using structured illumination microscopy. We tested mitochondrial stress caused by toxins related to PD, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP/MPP+) and carbonyl cyanide m-chlorophenyl hydrazone (CCCP) and found that a-syn prevents recovery of stimulated mitochondrial Ca2+ uptake. The C-terminal tail, and not N-terminal helices, is involved in this inhibitory activity, which is abrogated when phosphorylation site serine-129 is mutated (S129A). Correspondingly, we find that MPTP/MPP+ and CCCP stress is accompanied by both phosphorylation (pS129) and aggregation of a-syn. Overall, our results indicate that a-syn can participate as a tethering protein to modulate Ca2+ flux between ER and mitochondria, with potential physiological significance. A-syn can also prevent cellular recovery from toxin-induced mitochondrial dysfunction, which may represent a pathological role of a-syn in the etiology of PD.
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Affiliation(s)
- Meraj Ramezani
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | | | - Tong Wang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - David A Holowka
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - David Eliezer
- Department of Biochemistry, Weill Cornell Medicine, New York, NY, 10065, USA.
| | - Barbara A Baird
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA.
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18
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Dridi H, Santulli G, Bahlouli L, Miotto MC, Weninger G, Marks AR. Mitochondrial Calcium Overload Plays a Causal Role in Oxidative Stress in the Failing Heart. Biomolecules 2023; 13:1409. [PMID: 37759809 PMCID: PMC10527470 DOI: 10.3390/biom13091409] [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: 08/17/2023] [Revised: 09/13/2023] [Accepted: 09/17/2023] [Indexed: 09/29/2023] Open
Abstract
Heart failure is a serious global health challenge, affecting more than 6.2 million people in the United States and is projected to reach over 8 million by 2030. Independent of etiology, failing hearts share common features, including defective calcium (Ca2+) handling, mitochondrial Ca2+ overload, and oxidative stress. In cardiomyocytes, Ca2+ not only regulates excitation-contraction coupling, but also mitochondrial metabolism and oxidative stress signaling, thereby controlling the function and actual destiny of the cell. Understanding the mechanisms of mitochondrial Ca2+ uptake and the molecular pathways involved in the regulation of increased mitochondrial Ca2+ influx is an ongoing challenge in order to identify novel therapeutic targets to alleviate the burden of heart failure. In this review, we discuss the mechanisms underlying altered mitochondrial Ca2+ handling in heart failure and the potential therapeutic strategies.
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Affiliation(s)
- Haikel Dridi
- Department of Physiology and Cellular Biophysics, Clyde and Helen Wu Center for Molecular Cardiology, Columbia University Vagelos College of Physicians & Surgeons, New York, NY 10032, USA; (L.B.); (M.C.M.); (G.W.); (A.R.M.)
| | - Gaetano Santulli
- Department of Medicine, Division of Cardiology, Wilf Family Cardiovascular Research Institute, Albert Einstein College of Medicine, New York, NY 10461, USA;
| | - Laith Bahlouli
- Department of Physiology and Cellular Biophysics, Clyde and Helen Wu Center for Molecular Cardiology, Columbia University Vagelos College of Physicians & Surgeons, New York, NY 10032, USA; (L.B.); (M.C.M.); (G.W.); (A.R.M.)
| | - Marco C. Miotto
- Department of Physiology and Cellular Biophysics, Clyde and Helen Wu Center for Molecular Cardiology, Columbia University Vagelos College of Physicians & Surgeons, New York, NY 10032, USA; (L.B.); (M.C.M.); (G.W.); (A.R.M.)
| | - Gunnar Weninger
- Department of Physiology and Cellular Biophysics, Clyde and Helen Wu Center for Molecular Cardiology, Columbia University Vagelos College of Physicians & Surgeons, New York, NY 10032, USA; (L.B.); (M.C.M.); (G.W.); (A.R.M.)
| | - Andrew R. Marks
- Department of Physiology and Cellular Biophysics, Clyde and Helen Wu Center for Molecular Cardiology, Columbia University Vagelos College of Physicians & Surgeons, New York, NY 10032, USA; (L.B.); (M.C.M.); (G.W.); (A.R.M.)
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19
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D’Angelo D, Rizzuto R. The Mitochondrial Calcium Uniporter (MCU): Molecular Identity and Role in Human Diseases. Biomolecules 2023; 13:1304. [PMID: 37759703 PMCID: PMC10526485 DOI: 10.3390/biom13091304] [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: 07/27/2023] [Revised: 08/22/2023] [Accepted: 08/22/2023] [Indexed: 09/29/2023] Open
Abstract
Calcium (Ca2+) ions act as a second messenger, regulating several cell functions. Mitochondria are critical organelles for the regulation of intracellular Ca2+. Mitochondrial calcium (mtCa2+) uptake is ensured by the presence in the inner mitochondrial membrane (IMM) of the mitochondrial calcium uniporter (MCU) complex, a macromolecular structure composed of pore-forming and regulatory subunits. MtCa2+ uptake plays a crucial role in the regulation of oxidative metabolism and cell death. A lot of evidence demonstrates that the dysregulation of mtCa2+ homeostasis can have serious pathological outcomes. In this review, we briefly discuss the molecular structure and the function of the MCU complex and then we focus our attention on human diseases in which a dysfunction in mtCa2+ has been shown.
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Affiliation(s)
- Donato D’Angelo
- Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy;
| | - Rosario Rizzuto
- Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy;
- National Center on Gene Therapy and RNA-Based Drugs, 35131 Padua, Italy
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20
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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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21
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Li C, Sun J, Zhang X, Zhou M, Gan X. Implications of MCU complex in metabolic diseases. FASEB J 2023; 37:e23046. [PMID: 37389546 DOI: 10.1096/fj.202300218r] [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: 02/07/2023] [Revised: 05/17/2023] [Accepted: 06/07/2023] [Indexed: 07/01/2023]
Abstract
Metabolic diseases are considered the primary culprit for physical and mental health of individuals. Although the diagnosis of these diseases is relatively easy, more effective and convenient potent drugs are still being explored. Ca2+ across the inner mitochondrial membrane is a vital intracellular messenger that regulates energy metabolism and cellular Ca2+ homeostasis and is involved in cell death. Mitochondria rely on a selective mitochondrial Ca2+ unidirectional transport complex (MCU complex) in their inner membrane for Ca2+ uptake. We found that the channel contains several subunits and undergoes dramatic transformations in various pathological processes, especially in metabolic diseases. In this way, we believe that the MCU complex becomes a target with significant potential for these diseases. However, there is no review linking the two factors, thus hindering the possibility of new drug production. Here, we highlight the connection between MCU complex-related Ca2+ transport and the pathophysiology of metabolic diseases, adding understanding and insight at the molecular level to provide new insights for targeting MCU to reverse metabolism-related diseases.
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Affiliation(s)
- Chen Li
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Jiyu Sun
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Xidan Zhang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Min Zhou
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Xueqi Gan
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
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22
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Chapoy Villanueva H, Sung JH, Stevens JA, Zhang MJ, Nelson PM, Denduluri LS, Feng F, O'Connell TD, Townsend D, Liu JC. Distinct effects of cardiac mitochondrial calcium uniporter inactivation via EMRE deletion in the short and long term. J Mol Cell Cardiol 2023; 181:33-45. [PMID: 37230379 PMCID: PMC10524693 DOI: 10.1016/j.yjmcc.2023.05.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 05/13/2023] [Accepted: 05/18/2023] [Indexed: 05/27/2023]
Abstract
Transport of Ca2+ into mitochondria is thought to stimulate the production of ATP, a critical process in the heart's fight or flight response, but excess Ca2+ can trigger cell death. The mitochondrial Ca2+ uniporter complex is the primary route of Ca2+ transport into mitochondria, in which the channel-forming protein MCU and the regulatory protein EMRE are essential for activity. In previous studies, chronic Mcu or Emre deletion differed from acute cardiac Mcu deletion in response to adrenergic stimulation and ischemia/reperfusion (I/R) injury, despite equivalent inactivation of rapid mitochondrial Ca2+ uptake. To explore this discrepancy between chronic and acute loss of uniporter activity, we compared short-term and long-term Emre deletion using a novel conditional cardiac-specific, tamoxifen-inducible mouse model. After short-term Emre deletion (3 weeks post-tamoxifen) in adult mice, cardiac mitochondria were unable to take up Ca2+, had lower basal mitochondrial Ca2+ levels, and displayed attenuated Ca2+-induced ATP production and mPTP opening. Moreover, short-term EMRE loss blunted cardiac response to adrenergic stimulation and improved maintenance of cardiac function in an ex vivo I/R model. We then tested whether the long-term absence of EMRE (3 months post-tamoxifen) in adulthood would lead to distinct outcomes. After long-term Emre deletion, mitochondrial Ca2+ handling and function, as well as cardiac response to adrenergic stimulation, were similarly impaired as in short-term deletion. Interestingly, however, protection from I/R injury was lost in the long-term. These data suggest that several months without uniporter function are insufficient to restore bioenergetic response but are sufficient to restore susceptibility to I/R.
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Affiliation(s)
- Hector Chapoy Villanueva
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Jae Hwi Sung
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Jackie A Stevens
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Michael J Zhang
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA; Cardiovascular Division, Department of Medicine, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Peyton M Nelson
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Lalitha S Denduluri
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Feng Feng
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Timothy D O'Connell
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - DeWayne Townsend
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Julia C Liu
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA.
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23
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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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24
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Cao R, Tian H, Zhang Y, Liu G, Xu H, Rao G, Tian Y, Fu X. Signaling pathways and intervention for therapy of type 2 diabetes mellitus. MedComm (Beijing) 2023; 4:e283. [PMID: 37303813 PMCID: PMC10248034 DOI: 10.1002/mco2.283] [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: 01/06/2023] [Revised: 04/18/2023] [Accepted: 04/27/2023] [Indexed: 06/13/2023] Open
Abstract
Type 2 diabetes mellitus (T2DM) represents one of the fastest growing epidemic metabolic disorders worldwide and is a strong contributor for a broad range of comorbidities, including vascular, visual, neurological, kidney, and liver diseases. Moreover, recent data suggest a mutual interplay between T2DM and Corona Virus Disease 2019 (COVID-19). T2DM is characterized by insulin resistance (IR) and pancreatic β cell dysfunction. Pioneering discoveries throughout the past few decades have established notable links between signaling pathways and T2DM pathogenesis and therapy. Importantly, a number of signaling pathways substantially control the advancement of core pathological changes in T2DM, including IR and β cell dysfunction, as well as additional pathogenic disturbances. Accordingly, an improved understanding of these signaling pathways sheds light on tractable targets and strategies for developing and repurposing critical therapies to treat T2DM and its complications. In this review, we provide a brief overview of the history of T2DM and signaling pathways, and offer a systematic update on the role and mechanism of key signaling pathways underlying the onset, development, and progression of T2DM. In this content, we also summarize current therapeutic drugs/agents associated with signaling pathways for the treatment of T2DM and its complications, and discuss some implications and directions to the future of this field.
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Affiliation(s)
- Rong Cao
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
| | - Huimin Tian
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China Medical School, West China HospitalSichuan UniversityChengduSichuanChina
| | - Yu Zhang
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China Medical School, West China HospitalSichuan UniversityChengduSichuanChina
| | - Geng Liu
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
| | - Haixia Xu
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
| | - Guocheng Rao
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China Medical School, West China HospitalSichuan UniversityChengduSichuanChina
| | - Yan Tian
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
| | - Xianghui Fu
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan University and Collaborative Innovation Center of BiotherapyChengduSichuanChina
- Department of Endocrinology and MetabolismState Key Laboratory of Biotherapy and Cancer CenterWest China Medical School, West China HospitalSichuan UniversityChengduSichuanChina
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25
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Caroccia B, Seccia TM, Pallafacchina G, Piazza M, Caputo I, Zamberlan S, Rizzuto R, Rossi GP. Aldosterone Biosynthesis Is Potently Stimulated by Perfluoroalkyl Acids: A Link between Common Environmental Pollutants and Arterial Hypertension. Int J Mol Sci 2023; 24:ijms24119376. [PMID: 37298327 DOI: 10.3390/ijms24119376] [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: 05/06/2023] [Revised: 05/19/2023] [Accepted: 05/25/2023] [Indexed: 06/12/2023] Open
Abstract
The large environmental contamination of drinking water by perfluoroalkyl substances (PFAS) markedly increased the plasma levels of pentadecafluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) in a Northern Italy population with a high prevalence of arterial hypertension and cardiovascular disease. As the link between PFAS and arterial hypertension is unknown, we investigated if they enhance the biosynthesis of the well-known pressor hormone aldosterone. We found that PFAS increased aldosterone synthase (CYP11B2) gene expression by three-fold and doubled aldosterone secretion and cell and mitochondria reactive oxygen species (ROS) production over controls (p < 0.01 for all) in human adrenocortical carcinoma cells HAC15. They also enhanced the effects of Ang II on CYP11B2 mRNA and aldosterone secretion (p < 0.01 for all). Moreover, when added 1 h before, the ROS scavenger tempol abolished the effect of PFAS on CYP11B2 gene expression. These results indicate that at concentrations mimicking those found in human plasma of exposed individuals, PFAS are potent disruptors of human adrenocortical cell function, and might act as causative factors of human arterial hypertension via increased aldosterone production.
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Affiliation(s)
- Brasilina Caroccia
- Internal Emergency Medicine Unit, Specialized Center for Blood Pressure Disorders-Regione Veneto, Department of Medicine-DIMED, University of Padua, 35131 Padua, Italy
| | - Teresa Maria Seccia
- Internal Emergency Medicine Unit, Specialized Center for Blood Pressure Disorders-Regione Veneto, Department of Medicine-DIMED, University of Padua, 35131 Padua, Italy
| | - Giorgia Pallafacchina
- Department of Biomedical Sciences-DSB, University of Padua, 35131 Padua, Italy
- Neuroscience Institute, Italian National Research Council (CNR), 35131 Padua, Italy
| | - Maria Piazza
- Internal Emergency Medicine Unit, Specialized Center for Blood Pressure Disorders-Regione Veneto, Department of Medicine-DIMED, University of Padua, 35131 Padua, Italy
| | - Ilaria Caputo
- Internal Emergency Medicine Unit, Specialized Center for Blood Pressure Disorders-Regione Veneto, Department of Medicine-DIMED, University of Padua, 35131 Padua, Italy
| | - Stefania Zamberlan
- Internal Emergency Medicine Unit, Specialized Center for Blood Pressure Disorders-Regione Veneto, Department of Medicine-DIMED, University of Padua, 35131 Padua, Italy
| | - Rosario Rizzuto
- Department of Biomedical Sciences-DSB, University of Padua, 35131 Padua, Italy
| | - Gian Paolo Rossi
- Internal Emergency Medicine Unit, Specialized Center for Blood Pressure Disorders-Regione Veneto, Department of Medicine-DIMED, University of Padua, 35131 Padua, Italy
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26
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Szabo I, Szewczyk A. Mitochondrial Ion Channels. Annu Rev Biophys 2023; 52:229-254. [PMID: 37159294 DOI: 10.1146/annurev-biophys-092622-094853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Mitochondria are involved in multiple cellular tasks, such as ATP synthesis, metabolism, metabolite and ion transport, regulation of apoptosis, inflammation, signaling, and inheritance of mitochondrial DNA. The majority of the correct functioning of mitochondria is based on the large electrochemical proton gradient, whose component, the inner mitochondrial membrane potential, is strictly controlled by ion transport through mitochondrial membranes. Consequently, mitochondrial function is critically dependent on ion homeostasis, the disturbance of which leads to abnormal cell functions. Therefore, the discovery of mitochondrial ion channels influencing ion permeability through the membrane has defined a new dimension of the function of ion channels in different cell types, mainly linked to the important tasks that mitochondrial ion channels perform in cell life and death. This review summarizes studies on animal mitochondrial ion channels with special focus on their biophysical properties, molecular identity, and regulation. Additionally, the potential of mitochondrial ion channels as therapeutic targets for several diseases is briefly discussed.
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Affiliation(s)
- Ildiko Szabo
- Department of Biology, University of Padova, Italy;
| | - Adam Szewczyk
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland;
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27
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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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MacEwen MJ, Sancak Y. Beyond the matrix: structural and physiological advancements in mitochondrial calcium signaling. Biochem Soc Trans 2023; 51:665-673. [PMID: 36960768 PMCID: PMC10212541 DOI: 10.1042/bst20220317] [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] [Received: 01/31/2023] [Revised: 03/08/2023] [Accepted: 03/10/2023] [Indexed: 03/25/2023]
Abstract
Mitochondrial calcium (Ca2+) signaling has long been known to regulate diverse cellular functions, ranging from ATP production via oxidative phosphorylation, to cytoplasmic Ca2+ signaling to apoptosis. Central to mitochondrial Ca2+ signaling is the mitochondrial Ca2+ uniporter complex (MCUC) which enables Ca2+ flux from the cytosol into the mitochondrial matrix. Several pivotal discoveries over the past 15 years have clarified the identity of the proteins comprising MCUC. Here, we provide an overview of the literature on mitochondrial Ca2+ biology and highlight recent findings on the high-resolution structure, dynamic regulation, and new functions of MCUC, with an emphasis on publications from the last five years. We discuss the importance of these findings for human health and the therapeutic potential of targeting mitochondrial Ca2+ signaling.
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Affiliation(s)
| | - Yasemin Sancak
- Department of Pharmacology, University of Washington, Seattle, WA 98195, U.S.A
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29
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de Ridder I, Kerkhofs M, Lemos FO, Loncke J, Bultynck G, Parys JB. The ER-mitochondria interface, where Ca 2+ and cell death meet. Cell Calcium 2023; 112:102743. [PMID: 37126911 DOI: 10.1016/j.ceca.2023.102743] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 04/20/2023] [Accepted: 04/24/2023] [Indexed: 05/03/2023]
Abstract
Endoplasmic reticulum (ER)-mitochondria contact sites are crucial to allow Ca2+ flux between them and a plethora of proteins participate in tethering both organelles together. Inositol 1,4,5-trisphosphate receptors (IP3Rs) play a pivotal role at such contact sites, participating in both ER-mitochondria tethering and as Ca2+-transport system that delivers Ca2+ from the ER towards mitochondria. At the ER-mitochondria contact sites, the IP3Rs function as a multi-protein complex linked to the voltage-dependent anion channel 1 (VDAC1) in the outer mitochondrial membrane, via the chaperone glucose-regulated protein 75 (GRP75). This IP3R-GRP75-VDAC1 complex supports the efficient transfer of Ca2+ from the ER into the mitochondrial intermembrane space, from which the Ca2+ ions can reach the mitochondrial matrix through the mitochondrial calcium uniporter. Under physiological conditions, basal Ca2+ oscillations deliver Ca2+ to the mitochondrial matrix, thereby stimulating mitochondrial oxidative metabolism. However, when mitochondrial Ca2+ overload occurs, the increase in [Ca2+] will induce the opening of the mitochondrial permeability transition pore, thereby provoking cell death. The IP3R-GRP75-VDAC1 complex forms a hub for several other proteins that stabilize the complex and/or regulate the complex's ability to channel Ca2+ into the mitochondria. These proteins and their mechanisms of action are discussed in the present review with special attention for their role in pathological conditions and potential implication for therapeutic strategies.
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Affiliation(s)
- Ian de Ridder
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Martijn Kerkhofs
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Fernanda O Lemos
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Jens Loncke
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Geert Bultynck
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium.
| | - Jan B Parys
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium.
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Ramezani M, Wagenknecht-Wiesner A, Wang T, Holowka DA, Eliezer D, Baird BA. Alpha Synuclein Modulates Mitochondrial Ca 2+ Uptake from ER During Cell Stimulation and Under Stress Conditions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.23.537965. [PMID: 37163091 PMCID: PMC10168219 DOI: 10.1101/2023.04.23.537965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Alpha synuclein (a-syn) is an intrinsically disordered protein prevalent in neurons, and aggregated forms are associated with synucleinopathies including Parkinson' disease (PD). Despite the biomedical importance and extensive studies, the physiological role of a-syn and its participation in etiology of PD remain uncertain. We showed previously in model RBL cells that a-syn colocalizes with mitochondrial membranes, depending on formation of N-terminal helices and increasing with mitochondrial stress. 1 We have now characterized this colocalization and functional correlates in RBL, HEK293, and N2a cells. We find that expression of a-syn enhances stimulated mitochondrial uptake of Ca 2+ from the ER, depending on formation of its N-terminal helices but not on its disordered C-terminal tail. Our results are consistent with a-syn acting as a tether between mitochondria and ER, and we show increased contacts between these two organelles using structured illumination microscopy. We tested mitochondrial stress caused by toxins related to PD, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP/MPP+) and carbonyl cyanide m-chlorophenyl hydrazone (CCCP), and found that a-syn prevents recovery of stimulated mitochondrial Ca 2+ uptake. The C-terminal tail, and not N-terminal helices, is involved in this inhibitory activity, which is abrogated when phosphorylation site serine-129 is mutated (S129A). Correspondingly, we find that MPTP/MPP+ and CCCP stress is accompanied by both phosphorylation (pS129) and aggregation of a-syn. Overall, our results indicate that a-syn can participate as a tethering protein to modulate Ca 2+ flux between ER and mitochondria, with potential physiological significance. A-syn can also prevent cellular recovery from toxin-induced mitochondrial dysfunction, which may represent a pathological role of a-syn in the etiology of PD.
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Affiliation(s)
- Meraj Ramezani
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853
| | | | - Tong Wang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853
| | - David A. Holowka
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853
| | - David Eliezer
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10065
| | - Barbara A. Baird
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853
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Garbincius JF, Luongo TS, Lambert JP, Mangold AS, Murray EK, Hildebrand AN, Jadiya P, Elrod JW. MCU gain- and loss-of-function models define the duality of mitochondrial calcium uptake in heart failure. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.17.537222. [PMID: 37131819 PMCID: PMC10153142 DOI: 10.1101/2023.04.17.537222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Background Mitochondrial calcium (mCa2+) uptake through the mitochondrial calcium uniporter channel (mtCU) stimulates metabolism to meet acute increases in cardiac energy demand. However, excessive mCa2+ uptake during stress, as in ischemia-reperfusion, initiates permeability transition and cell death. Despite these often-reported acute physiological and pathological effects, a major unresolved controversy is whether mtCU-dependent mCa2+ uptake and long-term elevation of cardiomyocyte mCa2+ contributes to the heart's adaptation during sustained increases in workload. Objective We tested the hypothesis that mtCU-dependent mCa2+ uptake contributes to cardiac adaptation and ventricular remodeling during sustained catecholaminergic stress. Methods Mice with tamoxifen-inducible, cardiomyocyte-specific gain (αMHC-MCM × flox-stop-MCU; MCU-Tg) or loss (αMHC-MCM × Mcufl/fl; Mcu-cKO) of mtCU function received 2-wk catecholamine infusion. Results Cardiac contractility increased after 2d of isoproterenol in control, but not Mcu-cKO mice. Contractility declined and cardiac hypertrophy increased after 1-2-wk of isoproterenol in MCU-Tg mice. MCU-Tg cardiomyocytes displayed increased sensitivity to Ca2+- and isoproterenol-induced necrosis. However, loss of the mitochondrial permeability transition pore (mPTP) regulator cyclophilin D failed to attenuate contractile dysfunction and hypertrophic remodeling, and increased isoproterenol-induced cardiomyocyte death in MCU-Tg mice. Conclusions mtCU mCa2+ uptake is required for early contractile responses to adrenergic signaling, even those occurring over several days. Under sustained adrenergic load excessive MCU-dependent mCa2+ uptake drives cardiomyocyte dropout, perhaps independent of classical mitochondrial permeability transition pore opening, and compromises contractile function. These findings suggest divergent consequences for acute versus sustained mCa2+ loading, and support distinct functional roles for the mPTP in settings of acute mCa2+ overload versus persistent mCa2+ stress.
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Affiliation(s)
- Joanne F. Garbincius
- Cardiovascular Research Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Timothy S. Luongo
- Cardiovascular Research Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Jonathan P. Lambert
- Cardiovascular Research Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Adam S. Mangold
- Cardiovascular Research Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Emma K. Murray
- Cardiovascular Research Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Alycia N. Hildebrand
- Cardiovascular Research Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Pooja Jadiya
- Cardiovascular Research Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
- Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - John W. Elrod
- Cardiovascular Research Center, Department of Cardiovascular Sciences, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
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Zhou G, Ye Q, Xu Y, He B, Wu L, Zhu G, Xie J, Yao L, Xiao Z. Mitochondrial calcium uptake 3 mitigates cerebral amyloid angiopathy-related neuronal death and glial inflammation by reducing mitochondrial dysfunction. Int Immunopharmacol 2023; 117:109614. [PMID: 36878048 DOI: 10.1016/j.intimp.2022.109614] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 12/10/2022] [Accepted: 12/16/2022] [Indexed: 03/06/2023]
Abstract
Cerebral amyloid angiopathy (CAA) is characterized by the cerebrovascular amyloid-β (Aβ) accumulation, and always accompanied by Alzheimer's disease (AD). Mitochondrial dysfunction-associated cellular events including cell death, inflammation and oxidative stress are implicated in the progression of CAA. Unfortunately, the molecular mechanisms revealing CAA pathogenesis are still obscure, thus requiring further studies. Mitochondrial calcium uptake 3 (MICU3), a regulator of the mitochondrial Ca2+ uniporter (MCU), mediates various biological functions, but its expression and influence on CAA are largely unknown. In the present study, we found that MICU3 expression was gradually declined in cortex and hippocampus of Tg-SwDI transgenic mice. Using stereotaxic operation with AAV9 encoding MICU3, we showed that AAV-MICU3 improved the behavioral performances and cerebral blood flow (CBF) in Tg-SwDI mice, along with markedly reduced Aβ deposition through mediating Aβ metabolism process. Importantly, we found that AAV-MICU3 remarkably improved neuronal death and mitigated glial activation and neuroinflammation in cortex and hippocampus of Tg-SwDI mice. Furthermore, excessive oxidative stress, mitochondrial impairment and dysfunction, decreased ATP and mitochondrial DNA (mtDNA) were detected in Tg-SwDI mice, while being considerably ameliorated upon MICU3 over-expression. More importantly, our in vitro experiments suggested that MICU3-attenuated neuronal death, activation of glial cells and oxidative stress were completely abrogated upon PTEN induced putative kinase 1 (PINK1) knockdown, indicating that PINK1 was required for MICU3 to perform its protective effects against CAA. Mechanistic experiment confirmed an interaction between MICU3 and PINK1. Together, these findings demonstrated that MICU3-PINK1 axis may serve as a key target for CAA treatment mainly through improving mitochondrial dysfunction.
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Affiliation(s)
- Guijuan Zhou
- Department of Neurology, the First Affiliated Hospital, University of South China, 69 Chuanshan Road, Hengyang, Hunan, PR China; Department of Rehabilitation Medicine, the First Affiliated Hospital, University of South China, 69 Chuanshan Road, Hengyang, Hunan, PR China
| | - Qing Ye
- Department of Neurology, the First Affiliated Hospital, University of South China, 69 Chuanshan Road, Hengyang, Hunan, PR China
| | - Yan Xu
- Department of Neurology, the First Affiliated Hospital, University of South China, 69 Chuanshan Road, Hengyang, Hunan, PR China
| | - Bing He
- Department of Neurology, the First Affiliated Hospital, University of South China, 69 Chuanshan Road, Hengyang, Hunan, PR China
| | - Lin Wu
- Department of Neurology, the First Affiliated Hospital, University of South China, 69 Chuanshan Road, Hengyang, Hunan, PR China
| | - Guanghua Zhu
- Department of Neurology, the First Affiliated Hospital, University of South China, 69 Chuanshan Road, Hengyang, Hunan, PR China
| | - Juan Xie
- Department of Neurology, the First Affiliated Hospital, University of South China, 69 Chuanshan Road, Hengyang, Hunan, PR China
| | - Lan Yao
- Department of Neurology, the First Affiliated Hospital, University of South China, 69 Chuanshan Road, Hengyang, Hunan, PR China
| | - Zijian Xiao
- Department of Neurology, the First Affiliated Hospital, University of South China, 69 Chuanshan Road, Hengyang, Hunan, PR China.
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Lozano O, Marcos P, Salazar-Ramirez FDJ, Lázaro-Alfaro AF, Sobrevia L, García-Rivas G. Targeting the mitochondrial Ca 2+ uniporter complex in cardiovascular disease. Acta Physiol (Oxf) 2023; 237:e13946. [PMID: 36751976 DOI: 10.1111/apha.13946] [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: 07/21/2022] [Revised: 02/02/2023] [Accepted: 02/03/2023] [Indexed: 02/09/2023]
Abstract
Cardiovascular diseases (CVDs), the leading cause of death worldwide, share in common mitochondrial dysfunction, in specific a dysregulation of Ca2+ uptake dynamics through the mitochondrial Ca2+ uniporter (MCU) complex. In particular, Ca2+ uptake regulates the mitochondrial ATP production, mitochondrial dynamics, oxidative stress, and cell death. Therefore, modulating the activity of the MCU complex to regulate Ca2+ uptake, has been suggested as a potential therapeutic approach for the treatment of CVDs. Here, the role and implications of the MCU complex in CVDs are presented, followed by a review of the evidence for MCU complex modulation, genetically and pharmacologically. While most approaches have aimed within the MCU complex for the modulation of the Ca2+ pore channel, the MCU subunit, its intra- and extra- mitochondrial implications, including Ca2+ dynamics, oxidative stress, post-translational modifications, and its repercussions in the cardiac function, highlight that targeting the MCU complex has the translational potential for novel CVDs therapeutics.
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Affiliation(s)
- Omar Lozano
- Cátedra de Cardiología y Medicina Vascular, School of Medicine and Health Sciences, Tecnologico de Monterrey, Monterrey, Mexico
- Biomedical Research Center, Hospital Zambrano-Hellion, TecSalud, Tecnologico de Monterrey, San Pedro Garza García, Mexico
- The Institute for Obesity Research, Tecnologico de Monterrey, Monterrey, Mexico
| | - Patricio Marcos
- Cátedra de Cardiología y Medicina Vascular, School of Medicine and Health Sciences, Tecnologico de Monterrey, Monterrey, Mexico
| | - Felipe de Jesús Salazar-Ramirez
- Cátedra de Cardiología y Medicina Vascular, School of Medicine and Health Sciences, Tecnologico de Monterrey, Monterrey, Mexico
| | - Anay F Lázaro-Alfaro
- Cátedra de Cardiología y Medicina Vascular, School of Medicine and Health Sciences, Tecnologico de Monterrey, Monterrey, Mexico
| | - Luis Sobrevia
- The Institute for Obesity Research, Tecnologico de Monterrey, Monterrey, Mexico
- Cellular and Molecular Physiology Laboratory, Department of Obstetrics, Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
- Department of Physiology, Faculty of Pharmacy, Universidad de Sevilla, Seville, Spain
- University of Queensland Centre for Clinical Research (UQCCR), Faculty of Medicine and Biomedical Sciences, University of Queensland, Herston, Queensland, Australia
| | - Gerardo García-Rivas
- Cátedra de Cardiología y Medicina Vascular, School of Medicine and Health Sciences, Tecnologico de Monterrey, Monterrey, Mexico
- Biomedical Research Center, Hospital Zambrano-Hellion, TecSalud, Tecnologico de Monterrey, San Pedro Garza García, Mexico
- The Institute for Obesity Research, Tecnologico de Monterrey, Monterrey, Mexico
- Center of Functional Medicine, Hospital Zambrano-Hellion, TecSalud, Tecnologico de Monterrey, San Pedro Garza García, Mexico
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Mitochondrial Ca2+ handling as a cell signaling hub: lessons from astrocyte function. Essays Biochem 2023; 67:63-75. [PMID: 36636961 DOI: 10.1042/ebc20220094] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 12/16/2022] [Accepted: 12/22/2022] [Indexed: 01/14/2023]
Abstract
Astrocytes are a heterogenous population of macroglial cells spread throughout the central nervous system with diverse functions, expression signatures, and intricate morphologies. Their subcellular compartments contain a distinct range of mitochondria, with functional microdomains exhibiting widespread activities, such as controlling local metabolism and Ca2+ signaling. Ca2+ is an ion of utmost importance, both physiologically and pathologically, and participates in critical central nervous system processes, including synaptic plasticity, neuron-astrocyte integration, excitotoxicity, and mitochondrial physiology and metabolism. The mitochondrial Ca2+ handling system is formed by the mitochondrial Ca2+ uniporter complex (MCUc), which mediates Ca2+ influx, and the mitochondrial Na+/Ca2+ exchanger (NCLX), responsible for most mitochondrial Ca2+ efflux, as well as additional components, including the mitochondrial permeability transition pore (mtPTP). Over the last decades, mitochondrial Ca2+ handling has been shown to be key for brain homeostasis, acting centrally in physiopathological processes such as astrogliosis, astrocyte-neuron activity integration, energy metabolism control, and neurodegeneration. In this review, we discuss the current state of knowledge regarding the mitochondrial Ca2+ handling system molecular composition, highlighting its impact on astrocytic homeostasis.
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Wang J, Yang S, Li H, Shen H, Lu X, Li X, Chen G. Downregulation of mitochondrial calcium uptake family 3 attenuates secondary brain injury after intracerebral hemorrhage in rats. Exp Neurol 2023; 361:114302. [PMID: 36549422 DOI: 10.1016/j.expneurol.2022.114302] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 11/28/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022]
Abstract
Intracerebral hemorrhage (ICH) is one type of stroke with a high incidence and mortality. Mitochondria provide energy for various life processes and regulate calcium-mediated signaling pathways by taking up calcium ions from cytoplasm. Mitochondrial calcium uptake family 3 (MICU3) is a tissue-specific enhancer of mitochondrial calcium uptake. The effects and mechanisms of MICU3 in ICH are unknown. In this study, we aimed to explore the role of MICU3 in ICH in rats and neuronal models. First, we constructed ICH model both in vivo and in vitro and observed increased expression of MICU3. Then lentivirus was transduced to knock down MICU3. We observed that knockdown of MICU3 significantly reduced mitochondrial uptake of calcium in primary neurons. Moreover, the downregulation of MICU3 attenuated cell apoptosis and decreased the accumulation of reactive oxygen species (ROS). Recovery of neurobehavioral and cognitive function also benefited from downregulation of MICU3. The findings demonstrated that MICU3 played an important role in cell apoptosis, oxidative stress, and maintenance of mitochondrial structure and function, and promoted rehabilitation of neurobehavior. In conclusion, MICU3 is expected to be a molecular marker and a potential therapeutic target for ICH.
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Affiliation(s)
- Jiahe Wang
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Institute of Stroke Research, Soochow University, 188 Shizi Street, Suzhou 215006, China
| | - Siyuan Yang
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Institute of Stroke Research, Soochow University, 188 Shizi Street, Suzhou 215006, China
| | - Haiying Li
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Institute of Stroke Research, Soochow University, 188 Shizi Street, Suzhou 215006, China
| | - Haitao Shen
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Institute of Stroke Research, Soochow University, 188 Shizi Street, Suzhou 215006, China
| | - Xiaocheng Lu
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Institute of Stroke Research, Soochow University, 188 Shizi Street, Suzhou 215006, China.
| | - Xiang Li
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Institute of Stroke Research, Soochow University, 188 Shizi Street, Suzhou 215006, China.
| | - Gang Chen
- Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China; Institute of Stroke Research, Soochow University, 188 Shizi Street, Suzhou 215006, China
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Mira RG, Quintanilla RA, Cerpa W. Mild Traumatic Brain Injury Induces Mitochondrial Calcium Overload and Triggers the Upregulation of NCLX in the Hippocampus. Antioxidants (Basel) 2023; 12:antiox12020403. [PMID: 36829963 PMCID: PMC9952386 DOI: 10.3390/antiox12020403] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 02/03/2023] [Accepted: 02/06/2023] [Indexed: 02/10/2023] Open
Abstract
Traumatic brain injury (TBI) is brain damage due to external forces. Mild TBI (mTBI) is the most common form of TBI, and repeated mTBI is a risk factor for developing neurodegenerative diseases. Several mechanisms of neuronal damage have been described in the cortex and hippocampus, including mitochondrial dysfunction. However, up until now, there have been no studies evaluating mitochondrial calcium dynamics. Here, we evaluated mitochondrial calcium dynamics in an mTBI model in mice using isolated hippocampal mitochondria for biochemical studies. We observed that 24 h after mTBI, there is a decrease in mitochondrial membrane potential and an increase in basal matrix calcium levels. These findings are accompanied by increased mitochondrial calcium efflux and no changes in mitochondrial calcium uptake. We also observed an increase in NCLX protein levels and calcium retention capacity. Our results suggest that under mTBI, the hippocampal cells respond by incrementing NCLX levels to restore mitochondrial function.
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Affiliation(s)
- Rodrigo G. Mira
- Laboratorio de Función y Patología Neuronal, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontifica Universidad Católica de Chile, Santiago 8331150, Chile
- Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas 6213515, Chile
| | - Rodrigo A. Quintanilla
- Laboratory of Neurodegenerative Diseases, Universidad Autónoma de Chile, Santiago 8910060, Chile
| | - Waldo Cerpa
- Laboratorio de Función y Patología Neuronal, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontifica Universidad Católica de Chile, Santiago 8331150, Chile
- Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas 6213515, Chile
- Correspondence:
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Walters GC, Usachev YM. Mitochondrial calcium cycling in neuronal function and neurodegeneration. Front Cell Dev Biol 2023; 11:1094356. [PMID: 36760367 PMCID: PMC9902777 DOI: 10.3389/fcell.2023.1094356] [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: 11/10/2022] [Accepted: 01/12/2023] [Indexed: 01/26/2023] Open
Abstract
Mitochondria are essential for proper cellular function through their critical roles in ATP synthesis, reactive oxygen species production, calcium (Ca2+) buffering, and apoptotic signaling. In neurons, Ca2+ buffering is particularly important as it helps to shape Ca2+ signals and to regulate numerous Ca2+-dependent functions including neuronal excitability, synaptic transmission, gene expression, and neuronal toxicity. Over the past decade, identification of the mitochondrial Ca2+ uniporter (MCU) and other molecular components of mitochondrial Ca2+ transport has provided insight into the roles that mitochondrial Ca2+ regulation plays in neuronal function in health and disease. In this review, we discuss the many roles of mitochondrial Ca2+ uptake and release mechanisms in normal neuronal function and highlight new insights into the Ca2+-dependent mechanisms that drive mitochondrial dysfunction in neurologic diseases including epilepsy, Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. We also consider how targeting Ca2+ uptake and release mechanisms could facilitate the development of novel therapeutic strategies for neurological diseases.
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Affiliation(s)
- Grant C. Walters
- Department of Neuroscience and Pharmacology, Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, United States
| | - Yuriy M. Usachev
- Department of Neuroscience and Pharmacology, Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, United States
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Pan D, Xu L, Shi D, Guo M. Knowledge mapping of mitochondrial calcium uniporter from 2011 to 2022: A bibliometric analysis. Front Physiol 2023; 14:1107328. [PMID: 36744031 PMCID: PMC9895098 DOI: 10.3389/fphys.2023.1107328] [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: 01/11/2023] [Indexed: 01/21/2023] Open
Abstract
Background: Calcium uptake research has a long history. However, the mitochondrial calcium uniporter (MCU) protein was first discovered in 2011. As investigations of mitochondrial calcium uniporter represent a new research hotspot, a comprehensive and objective perspective of the field is lacking. Hence, this bibliometric analysis aimed to provide the current study status and trends related to mitochondrial calcium uniporter research in the past decade. Methods: Articles were acquired from the Web of Science Core Collection database. We quantified and visualized information regarding annual publications, journals, cocited journals, countries/regions, institutions, authors, and cocited authors by using CiteSpace 5.8. R3 and VOSviewer. In addition, we analysed the citation and keyword bursts related to mitochondrial calcium uniporter studies. Results: From 2011 to 2022, 1,030 articles were published by 5,050 authors from 1,145 affiliations and 62 countries or regions. The country with the most published articles was the United States. The institution with the most published articles was the University of Padua. Rosario Rizzuto published the most articles and was also the most cocited author. Cell Calcium published the largest number of articles, whereas Journal of Biological Chemistry had the most cocitations. The top 5 keywords related to pathological processes were oxidative stress, cell death, permeability transition, apoptosis, and metabolism. MICU1, calcium, ryanodine receptor, ATP synthase and cyclophilin D were the top 5 keywords related to molecules. Conclusion: mitochondrial calcium uniporter research has grown stably over the last decade. Current studies focus on the structure of the mitochondrial calcium uniporter complex and its regulatory effect on mitochondrial calcium homeostasis. In addition, the potential role of mitochondrial calcium uniporter in different diseases has been explored. Current studies mostly involve investigations of cancer and neurodegenerative diseases. Our analysis provides guidance and new insights into further mitochondrial calcium uniporter research.
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Affiliation(s)
- Deng Pan
- Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China,National Clinical Research Centre for Chinese Medicine Cardiology, Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China,Graduate School of Beijing University of Chinese Medicine, Beijing, China
| | - Lin Xu
- Gynecological Department of Traditional Chinese Medicine, China-Japan Friendship Hospital, Beijing, China
| | - Dazhuo Shi
- Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China,National Clinical Research Centre for Chinese Medicine Cardiology, Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China,*Correspondence: Dazhuo Shi, ; Ming Guo,
| | - Ming Guo
- Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China,National Clinical Research Centre for Chinese Medicine Cardiology, Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China,*Correspondence: Dazhuo Shi, ; Ming Guo,
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Colussi DM, Stathopulos PB. From passage to inhibition: Uncovering the structural and physiological inhibitory mechanisms of MCUb in mitochondrial calcium regulation. FASEB J 2023; 37:e22678. [PMID: 36538269 PMCID: PMC10107711 DOI: 10.1096/fj.202201080r] [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: 07/07/2022] [Revised: 10/14/2022] [Accepted: 11/21/2022] [Indexed: 12/24/2022]
Abstract
Mitochondrial calcium (Ca2+ ) regulation is critically implicated in the regulation of bioenergetics and cell fate. Ca2+ , a universal signaling ion, passively diffuses into the mitochondrial intermembrane space (IMS) through voltage-dependent anion channels (VDAC), where uptake into the matrix is tightly regulated across the inner mitochondrial membrane (IMM) by the mitochondrial Ca2+ uniporter complex (mtCU). In recent years, immense progress has been made in identifying and characterizing distinct structural and physiological mechanisms of mtCU component function. One of the main regulatory components of the Ca2+ selective mtCU channel is the mitochondrial Ca2+ uniporter dominant-negative beta subunit (MCUb). The structural mechanisms underlying the inhibitory effect(s) exerted by MCUb are poorly understood, despite high homology to the main mitochondrial Ca2+ uniporter (MCU) channel-forming subunits. In this review, we provide an overview of the structural differences between MCUb and MCU, believed to contribute to the inhibition of mitochondrial Ca2+ uptake. We highlight the possible structural rationale for the absent interaction between MCUb and the mitochondrial Ca2+ uptake 1 (MICU1) gatekeeping subunit and a potential widening of the pore upon integration of MCUb into the channel. We discuss physiological and pathophysiological information known about MCUb, underscoring implications in cardiac function and arrhythmia as a basis for future therapeutic discovery. Finally, we discuss potential post-translational modifications on MCUb as another layer of important regulation.
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Affiliation(s)
- Danielle M Colussi
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Peter B Stathopulos
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
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40
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Kashif M, Sivaprakasam P, Vijendra P, Waseem M, Pandurangan AK. A Recent Update on Pathophysiology and Therapeutic Interventions of Alzheimer's Disease. Curr Pharm Des 2023; 29:3428-3441. [PMID: 38038007 DOI: 10.2174/0113816128264355231121064704] [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: 05/30/2023] [Revised: 10/09/2023] [Accepted: 10/19/2023] [Indexed: 12/02/2023]
Abstract
AIM Alzheimer's disease (AD) has been identified as a progressive brain disorder associated with memory dysfunction and the accumulation of β-amyloid plaques and neurofibrillary tangles of τ protein. Mitochondria is crucial in maintaining cell survival, cell death, calcium regulation, and ATP synthesis. Mitochondrial dysfunction and linked calcium overload have been involved in the pathogenesis of AD. CRM2 (Collapsin response mediator protein-2) is involved in endosomal lysosomal trafficking as well as autophagy, and their reduced level is also a primary culprit in the progression of AD. In addition, Cholinergic neurotransmission and neuroinflammation are two other mechanisms implicated in AD onset and might be protective targets to attenuate disease progression. The microbiota-gut-brain axis (MGBA) is another crucial target for AD treatment. Crosstalk between gut microbiota and brain mutually benefitted each other, dysbiosis in gut microbiota affects the brain functions and leads to AD progression with increased AD-causing biomarkers. Despite the complexity of AD, treatment is only limited to symptomatic management. Therefore, there is an urgent demand for novel therapeutics that target associated pathways responsible for AD pathology. This review explores the role of different mechanisms involved in AD and possible therapeutic targets to protect against disease progression. BACKGROUND Amidst various age-related diseases, AD is the most deleterious neurodegenerative disorder that affects more than 24 million people globally. Every year, approximately 7.7 million new cases of dementia have been reported. However, to date, no novel disease-modifying therapies are available to treat AD. OBJECTIVE The aim of writing this review is to highlight the role of key biomarker proteins and possible therapeutic interventions that could play a crucial role in mitigating the ongoing prognosis of Alzheimer's disease. MATERIALS AND METHODS The available information about the disease was collected through multiple search engines, including PubMed, Science Direct, Clinical Trials, and Google Scholar. RESULTS Accumulated pieces of evidence reveal that extracellular aggregation of β-amyloid plaques and intracellular tangles of τ protein are peculiar features of perpetuated Alzheimer's disease (AD). Further, the significant role of mitochondria, calcium, and cholinergic pathways in the pathogenesis of AD makes the respiratory cell organelle a crucial therapeutic target in this neurodegenerative disease. All currently available drugs either delay the clinical damage to cells or temporarily attenuate some symptoms of Alzheimer's disease. CONCLUSION The pathological features of AD are extracellular deposition of β-amyloid, acetylcholinesterase deregulation, and intracellular tangles of τ protein. The multifactorial heterogeneity of disease demands more research work in this field to find new therapeutic biological targets.
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Affiliation(s)
- Mohd Kashif
- School of Life Sciences, B.S. Abdur Rahman Crescent Institute of Science and Technology, Chennai, India
| | - Prathibha Sivaprakasam
- School of Life Sciences, B.S. Abdur Rahman Crescent Institute of Science and Technology, Chennai, India
| | - Poornima Vijendra
- Department of Studies in Food Technology, Davangere University, Davangere, Karnataka, India
| | - Mohammad Waseem
- Department of Pharmaceutical Science, University of Maryland, Eastern Shore, Baltimore, USA
| | - Ashok Kumar Pandurangan
- School of Life Sciences, B.S. Abdur Rahman Crescent Institute of Science and Technology, Chennai, India
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41
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Yoo J. Structural basis of Ca 2+ uptake by mitochondrial calcium uniporter in mitochondria: a brief review. BMB Rep 2022; 55:528-534. [PMID: 36195565 PMCID: PMC9712701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Indexed: 12/14/2022] Open
Abstract
Mitochondria are cellular organelles that perform various functions within cells. They are responsible for ATP production, cell-signal regulation, autophagy, and cell apoptosis. Because the mitochondrial proteins that perform these functions need Ca2+ ions for their activity, mitochondria have ion channels to selectively uptake Ca2+ ions from the cytoplasm. The ion channel known to play the most important role in the Ca2+ uptake in mitochondria is the mitochondrial calcium uniporter (MCU) holo-complex located in the inner mitochondrial membrane (IMM). This ion channel complex exists in the form of a complex consisting of the pore-forming protein through which the Ca2+ ions are transported into the mitochondrial matrix, and the auxiliary protein involved in regulating the activity of the Ca2+ uptake by the MCU holo-complex. Studies of this MCU holocomplex have long been conducted, but we didn't know in detail how mitochondria uptake Ca2+ ions through this ion channel complex or how the activity of this ion channel complex is regulated. Recently, the protein structure of the MCU holo-complex was identified, enabling the mechanism of Ca2+ uptake and its regulation by the MCU holo-complex to be confirmed. In this review, I will introduce the mechanism of action of the MCU holo-complex at the molecular level based on the Cryo-EM structure of the MCU holo-complex to help understand how mitochondria uptake the necessary Ca2+ ions through the MCU holo-complex and how these Ca2+ uptake mechanisms are regulated. [BMB Reports 2022; 55(11): 528-534].
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Affiliation(s)
- Jiho Yoo
- College of Pharmacy, Chung-Ang University, Seoul 06974, Korea,Corresponding author. Tel: +82-2-820-5673; E-mail:
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42
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Arnst N, Redolfi N, Lia A, Bedetta M, Greotti E, Pizzo P. Mitochondrial Ca 2+ Signaling and Bioenergetics in Alzheimer's Disease. Biomedicines 2022; 10:3025. [PMID: 36551781 PMCID: PMC9775979 DOI: 10.3390/biomedicines10123025] [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: 11/07/2022] [Revised: 11/17/2022] [Accepted: 11/22/2022] [Indexed: 11/25/2022] Open
Abstract
Alzheimer's disease (AD) is a hereditary and sporadic neurodegenerative illness defined by the gradual and cumulative loss of neurons in specific brain areas. The processes that cause AD are still under investigation and there are no available therapies to halt it. Current progress puts at the forefront the "calcium (Ca2+) hypothesis" as a key AD pathogenic pathway, impacting neuronal, astrocyte and microglial function. In this review, we focused on mitochondrial Ca2+ alterations in AD, their causes and bioenergetic consequences in neuronal and glial cells, summarizing the possible mechanisms linking detrimental mitochondrial Ca2+ signals to neuronal death in different experimental AD models.
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Affiliation(s)
- Nikita Arnst
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy
| | - Nelly Redolfi
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy
| | - Annamaria Lia
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy
- Neuroscience Institute, Italian National Research Council (CNR), 35131 Padua, Italy
| | - Martina Bedetta
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy
| | - Elisa Greotti
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy
- Neuroscience Institute, Italian National Research Council (CNR), 35131 Padua, Italy
- Padova Neuroscience Center (PNC), University of Padova, 35131 Padua, Italy
| | - Paola Pizzo
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy
- Neuroscience Institute, Italian National Research Council (CNR), 35131 Padua, Italy
- Study Centre for Neurodegeneration (CESNE), University of Padova, 35131 Padua, Italy
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43
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Capture at the ER-mitochondrial contacts licenses IP 3 receptors to stimulate local Ca 2+ transfer and oxidative metabolism. Nat Commun 2022; 13:6779. [PMID: 36351901 PMCID: PMC9646835 DOI: 10.1038/s41467-022-34365-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 10/24/2022] [Indexed: 11/10/2022] Open
Abstract
Endoplasmic reticulum-mitochondria contacts (ERMCs) are restructured in response to changes in cell state. While this restructuring has been implicated as a cause or consequence of pathology in numerous systems, the underlying molecular dynamics are poorly understood. Here, we show means to visualize the capture of motile IP3 receptors (IP3Rs) at ERMCs and document the immediate consequences for calcium signaling and metabolism. IP3Rs are of particular interest because their presence provides a scaffold for ERMCs that mediate local calcium signaling, and their function outside of ERMCs depends on their motility. Unexpectedly, in a cell model with little ERMC Ca2+ coupling, IP3Rs captured at mitochondria promptly mediate Ca2+ transfer, stimulating mitochondrial oxidative metabolism. The Ca2+ transfer does not require linkage with a pore-forming protein in the outer mitochondrial membrane. Thus, motile IP3Rs can traffic in and out of ERMCs, and, when 'parked', mediate calcium signal propagation to the mitochondria, creating a dynamic arrangement that supports local communication.
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44
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Yoo J. Structural basis of Ca 2+ uptake by mitochondrial calcium uniporter in mitochondria: a brief review. BMB Rep 2022; 55:528-534. [PMID: 36195565 PMCID: PMC9712701 DOI: 10.5483/bmbrep.2022.55.11.134] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 09/16/2022] [Accepted: 09/30/2022] [Indexed: 03/17/2024] Open
Abstract
Mitochondria are cellular organelles that perform various functions within cells. They are responsible for ATP production, cell-signal regulation, autophagy, and cell apoptosis. Because the mitochondrial proteins that perform these functions need Ca2+ ions for their activity, mitochondria have ion channels to selectively uptake Ca2+ ions from the cytoplasm. The ion channel known to play the most important role in the Ca2+ uptake in mitochondria is the mitochondrial calcium uniporter (MCU) holo-complex located in the inner mitochondrial membrane (IMM). This ion channel complex exists in the form of a complex consisting of the pore-forming protein through which the Ca2+ ions are transported into the mitochondrial matrix, and the auxiliary protein involved in regulating the activity of the Ca2+ uptake by the MCU holo-complex. Studies of this MCU holocomplex have long been conducted, but we didn't know in detail how mitochondria uptake Ca2+ ions through this ion channel complex or how the activity of this ion channel complex is regulated. Recently, the protein structure of the MCU holo-complex was identified, enabling the mechanism of Ca2+ uptake and its regulation by the MCU holo-complex to be confirmed. In this review, I will introduce the mechanism of action of the MCU holo-complex at the molecular level based on the Cryo-EM structure of the MCU holo-complex to help understand how mitochondria uptake the necessary Ca2+ ions through the MCU holo-complex and how these Ca2+ uptake mechanisms are regulated. [BMB Reports 2022; 55(11): 528-534].
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Affiliation(s)
- Jiho Yoo
- College of Pharmacy, Chung-Ang University, Seoul 06974, Korea
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45
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Tsai CW, Rodriguez MX, Van Keuren AM, Phillips CB, Shushunov HM, Lee JE, Garcia AM, Ambardekar AV, Cleveland JC, Reisz JA, Proenza C, Chatfield KC, Tsai MF. Mechanisms and significance of tissue-specific MICU regulation of the mitochondrial calcium uniporter complex. Mol Cell 2022; 82:3661-3676.e8. [PMID: 36206740 PMCID: PMC9557913 DOI: 10.1016/j.molcel.2022.09.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 05/16/2022] [Accepted: 09/07/2022] [Indexed: 12/29/2022]
Abstract
Mitochondrial Ca2+ uptake, mediated by the mitochondrial Ca2+ uniporter, regulates oxidative phosphorylation, apoptosis, and intracellular Ca2+ signaling. Previous studies suggest that non-neuronal uniporters are exclusively regulated by a MICU1-MICU2 heterodimer. Here, we show that skeletal-muscle and kidney uniporters also complex with a MICU1-MICU1 homodimer and that human/mouse cardiac uniporters are largely devoid of MICUs. Cells employ protein-importation machineries to fine-tune the relative abundance of MICU1 homo- and heterodimers and utilize a conserved MICU intersubunit disulfide to protect properly assembled dimers from proteolysis by YME1L1. Using the MICU1 homodimer or removing MICU1 allows mitochondria to more readily take up Ca2+ so that cells can produce more ATP in response to intracellular Ca2+ transients. However, the trade-off is elevated ROS, impaired basal metabolism, and higher susceptibility to death. These results provide mechanistic insights into how tissues can manipulate mitochondrial Ca2+ uptake properties to support their unique physiological functions.
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Affiliation(s)
- Chen-Wei Tsai
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Madison X Rodriguez
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Anna M Van Keuren
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Charles B Phillips
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Hannah M Shushunov
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Jessica E Lee
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Anastacia M Garcia
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Amrut V Ambardekar
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Joseph C Cleveland
- Department of Surgery, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Julie A Reisz
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Catherine Proenza
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Kathryn C Chatfield
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Ming-Feng Tsai
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
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Zampese E, Wokosin DL, Gonzalez-Rodriguez P, Guzman JN, Tkatch T, Kondapalli J, Surmeier WC, D’Alessandro KB, De Stefani D, Rizzuto R, Iino M, Molkentin JD, Chandel NS, Schumacker PT, Surmeier DJ. Ca 2+ channels couple spiking to mitochondrial metabolism in substantia nigra dopaminergic neurons. SCIENCE ADVANCES 2022; 8:eabp8701. [PMID: 36179023 PMCID: PMC9524841 DOI: 10.1126/sciadv.abp8701] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 08/12/2022] [Indexed: 05/08/2023]
Abstract
How do neurons match generation of adenosine triphosphate by mitochondria to the bioenergetic demands of regenerative activity? Although the subject of speculation, this coupling is still poorly understood, particularly in neurons that are tonically active. To help fill this gap, pacemaking substantia nigra dopaminergic neurons were studied using a combination of optical, electrophysiological, and molecular approaches. In these neurons, spike-activated calcium (Ca2+) entry through Cav1 channels triggered Ca2+ release from the endoplasmic reticulum, which stimulated mitochondrial oxidative phosphorylation through two complementary Ca2+-dependent mechanisms: one mediated by the mitochondrial uniporter and another by the malate-aspartate shuttle. Disrupting either mechanism impaired the ability of dopaminergic neurons to sustain spike activity. While this feedforward control helps dopaminergic neurons meet the bioenergetic demands associated with sustained spiking, it is also responsible for their elevated oxidant stress and possibly to their decline with aging and disease.
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Affiliation(s)
- Enrico Zampese
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - David L. Wokosin
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Patricia Gonzalez-Rodriguez
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Jaime N. Guzman
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Tatiana Tkatch
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Jyothisri Kondapalli
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - William C. Surmeier
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Karis B. D’Alessandro
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Diego De Stefani
- Department of Biomedical Sciences, University of Padova, Padova 35131, Italy
| | - Rosario Rizzuto
- Department of Biomedical Sciences, University of Padova, Padova 35131, Italy
| | - Masamitsu Iino
- Department of Physiology, Nihon University School of Medicine, 30-1, Oyaguchi Kami-cho, Itabashi-ku, Tokyo 173-8610, Japan
| | - Jeffery D. Molkentin
- Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Navdeep S. Chandel
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Paul T. Schumacker
- Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - D. James Surmeier
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
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Bachkoenig OA, Gottschalk B, Malli R, Graier WF. An unexpected effect of risperidone reveals a nonlinear relationship between cytosolic Ca 2+ and mitochondrial Ca 2+ uptake. CURRENT TOPICS IN MEMBRANES 2022; 90:13-35. [PMID: 36368872 DOI: 10.1016/bs.ctm.2022.09.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Mitochondria actively contribute to cellular Ca2+ homeostasis. The molecular mechanisms of mitochondrial Ca2+ uptake and release are well characterized and are attributed to the multi-protein assembly of the mitochondrial Ca2+ uniporter complex (MCUC) and the mitochondrial sodium-calcium exchanger (NCLX), respectively. Hence, Ca2+ transfer from the endoplasmic reticulum (ER) and store-operated Ca2+ entry (SOCE) into the mitochondrial matrix has been quantitatively visualized on the subcellular level using targeted fluorescent biosensors. However, a correlation between the amplitude of cytosolic Ca2+ elevation with that in the mitochondrial matrix has not been investigated in detail so far. In the present study, we combined the Ca2+-mobilizing agonist histamine with the H1-receptor antagonist risperidone to establish a well-tunable experimental approach allowing the correlation between low, slow, high, and fast cytosolic and mitochondrial Ca2+ signals in response to inositol 1,4,5-trisphosphate (IP3)-triggered ER Ca2+ release. Our present data confirm a defined threshold in cytosolic Ca2+, which is necessary for the activation of mitochondrial Ca2+ uptake. Moreover, our data support the hypothesis of different modes of mitochondrial Ca2+ uptake depending on the source of the ion (i.e., ER vs SOCE).
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Affiliation(s)
- Olaf A Bachkoenig
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Benjamin Gottschalk
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Roland Malli
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Wolfgang F Graier
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria.
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Groten CJ, MacVicar BA. Mitochondrial Ca 2+ uptake by the MCU facilitates pyramidal neuron excitability and metabolism during action potential firing. Commun Biol 2022; 5:900. [PMID: 36056095 PMCID: PMC9440007 DOI: 10.1038/s42003-022-03848-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 08/16/2022] [Indexed: 12/12/2022] Open
Abstract
Neuronal activation is fundamental to information processing by the brain and requires mitochondrial energy metabolism. Mitochondrial Ca2+ uptake by the mitochondrial Ca2+ uniporter (MCU) has long been implicated in the control of energy metabolism and intracellular Ca2+ signalling, but its importance to neuronal function in the brain remains unclear. Here, we used in situ electrophysiology and two-photon imaging of mitochondrial Ca2+, cytosolic Ca2+, and NAD(P)H to test the relevance of MCU activation to pyramidal neuron Ca2+ signalling and energy metabolism during action potential firing. We demonstrate that mitochondrial Ca2+ uptake by the MCU is tuned to enhanced firing rate and the strength of this relationship varied between neurons of discrete brain regions. MCU activation promoted electron transport chain activity and chemical reduction of NAD+ to NADH. Moreover, Ca2+ buffering by mitochondria attenuated cytosolic Ca2+ signals and thereby reduced the coupling between activity and the slow afterhyperpolarization, a ubiquitous regulator of excitability. Collectively, we demonstrate that the MCU is engaged by accelerated spike frequency to facilitate neuronal activity through simultaneous control of energy metabolism and excitability. As such, the MCU is situated to promote brain functions associated with high frequency signalling and may represent a target for controlling excessive neuronal activity.
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Affiliation(s)
- Christopher J Groten
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, V6T 1Z3, Canada.
| | - Brian A MacVicar
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, V6T 1Z3, Canada.
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IGF-1 receptor regulates upward firing rate homeostasis via the mitochondrial calcium uniporter. Proc Natl Acad Sci U S A 2022; 119:e2121040119. [PMID: 35943986 PMCID: PMC9388073 DOI: 10.1073/pnas.2121040119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
An emerging hypothesis is that neuronal circuits homeostatically maintain a stable spike rate despite continuous environmental changes. This firing rate homeostasis is believed to confer resilience to neurodegeneration and cognitive decline. We show that insulin-like growth factor-1 receptor (IGF-1R) is necessary for homeostatic response of mean firing rate to inactivity, termed “upward firing rate homeostasis.” We show that its mechanism of action is to couple spike bursts with downstream mitochondrial Ca2+ influx via the mitochondrial calcium uniporter complex (MCUc). We propose that MCUc is a homeostatic Ca2+ sensor that triggers the integrated homeostatic response. Firing rate homeostasis may be the principal mechanism by which IGF-1R regulates aging and neurodevelopmental and neurodegenerative disorders. Regulation of firing rate homeostasis constitutes a fundamental property of central neural circuits. While intracellular Ca2+ has long been hypothesized to be a feedback control signal, the molecular machinery enabling a network-wide homeostatic response remains largely unknown. We show that deletion of insulin-like growth factor-1 receptor (IGF-1R) limits firing rate homeostasis in response to inactivity, without altering the distribution of baseline firing rates. The deficient firing rate homeostatic response was due to disruption of both postsynaptic and intrinsic plasticity. At the cellular level, we detected a fraction of IGF-1Rs in mitochondria, colocalized with the mitochondrial calcium uniporter complex (MCUc). IGF-1R deletion suppressed transcription of the MCUc members and burst-evoked mitochondrial Ca2+ (mitoCa2+) by weakening mitochondria-to-cytosol Ca2+ coupling. Overexpression of either mitochondria-targeted IGF-1R or MCUc in IGF-1R–deficient neurons was sufficient to rescue the deficits in burst-to-mitoCa2+ coupling and firing rate homeostasis. Our findings indicate that mitochondrial IGF-1R is a key regulator of the integrated homeostatic response by tuning the reliability of burst transfer by MCUc. Based on these results, we propose that MCUc acts as a homeostatic Ca2+ sensor. Faulty activation of MCUc may drive dysregulation of firing rate homeostasis in aging and in brain disorders associated with aberrant IGF-1R/MCUc signaling.
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Reggiani C, Marcucci L. A controversial issue: Can mitochondria modulate cytosolic calcium and contraction of skeletal muscle fibers? J Gen Physiol 2022; 154:213356. [PMID: 35849108 PMCID: PMC9297197 DOI: 10.1085/jgp.202213167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Mitochondria are characterized by a high capacity to accumulate calcium thanks to the electrochemical gradient created by the extrusion of protons in the respiratory chain. Thereby calcium can enter crossing the inner mitochondrial membrane via MCU complex, a high-capacity, low-affinity transport mechanism. Calcium uptake serves numerous purposes, among them the regulation of three dehydrogenases of the citric cycle, apoptosis via permeability transition, and, in some cell types, modulation of cytosolic calcium transients. This Review is focused on mitochondrial calcium uptake in skeletal muscle fibers and aims to reanalyze its functional impact. In particular, we ask whether mitochondrial calcium uptake is relevant for the control of cytosolic calcium transients and therefore of contractile performance. Recent data suggest that this may be the case, at least in particular conditions, as modified expression of MCU complex subunits or of proteins involved in mitochondrial dynamics and ablation of the main cytosolic calcium buffer, parvalbumin.
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Affiliation(s)
- Carlo Reggiani
- Department of Biomedical Sciences, University of Padova, Padova, Italy,Science and Research Center Koper, Institute for Kinesiology Research, Koper, Slovenia,Correspondence to Carlo Reggiani:
| | - Lorenzo Marcucci
- Department of Biomedical Sciences, University of Padova, Padova, Italy,Center for Biosystems Dynamics Research, RIKEN, Suita, Japan
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