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Marcucci L, Nogara L, Canato M, Germinario E, Raffaello A, Carraro M, Bernardi P, Pietrangelo L, Boncompagni S, Protasi F, Paolocci N, Reggiani C. Mitochondria can substitute for parvalbumin to lower cytosolic calcium levels in the murine fast skeletal muscle. Acta Physiol (Oxf) 2024; 240:e14208. [PMID: 39077881 DOI: 10.1111/apha.14208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 07/09/2024] [Accepted: 07/15/2024] [Indexed: 07/31/2024]
Abstract
AIM Parvalbumin (PV) is a primary calcium buffer in mouse fast skeletal muscle fibers. Previous work showed that PV ablation has a limited impact on cytosolic Ca2+ ([Ca2+]cyto) transients and contractile response, while it enhances mitochondrial density and mitochondrial matrix-free calcium concentration ([Ca2+]mito). Here, we aimed to quantitatively test the hypothesis that mitochondria act to compensate for PV deficiency. METHODS We determined the free Ca2+ redistribution during a 2 s 60 Hz tetanic stimulation in the sarcoplasmic reticulum, cytosol, and mitochondria. Via a reaction-diffusion Ca2+ model, we quantitatively evaluated mitochondrial uptake and storage capacity requirements to compensate for PV lack and analyzed possible extracellular export. RESULTS [Ca2+]mito during tetanic stimulation is greater in knock-out (KO) (1362 ± 392 nM) than in wild-type (WT) (855 ± 392 nM), p < 0.05. Under the assumption of a non-linear intramitochondrial buffering, the model predicts an accumulation of 725 μmoles/L fiber (buffering ratio 1:11 000) in KO, much higher than in WT (137 μmoles/L fiber, ratio 1:4500). The required transport rate via mitochondrial calcium uniporter (MCU) reaches 3 mM/s, compatible with available literature. TEM images of calcium entry units and Mn2+ quenching showed a greater capacity of store-operated calcium entry in KO compared to WT. However, levels of [Ca2+]cyto during tetanic stimulation were not modulated to variations of extracellular calcium. CONCLUSIONS The model-based analysis of experimentally determined calcium distribution during tetanic stimulation showed that mitochondria can act as a buffer to compensate for the lack of PV. This result contributes to a better understanding of mitochondria's role in modulating [Ca2+]cyto in skeletal muscle fibers.
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Affiliation(s)
- Lorenzo Marcucci
- Department of Biomedical Sciences, University of Padova, Padova, Italy
- Center for Biosystems Dynamics Research, RIKEN, Suita, Japan
| | - Leonardo Nogara
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Marta Canato
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Elena Germinario
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Anna Raffaello
- Department of Biomedical Sciences, University of Padova, Padova, Italy
- Myology Center, University of Padova, Padova, Italy
| | - Michela Carraro
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Paolo Bernardi
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Laura Pietrangelo
- CAST, Center for Advanced Studies and Technology, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
- DMSI, Department of Medicine and Aging Sciences, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Simona Boncompagni
- CAST, Center for Advanced Studies and Technology, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
- DNICS, Department of Neuroscience and Clinical Sciences, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Feliciano Protasi
- CAST, Center for Advanced Studies and Technology, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
- DMSI, Department of Medicine and Aging Sciences, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Nazareno Paolocci
- Department of Biomedical Sciences, University of Padova, Padova, Italy
- Division of Cardiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Carlo Reggiani
- Department of Biomedical Sciences, University of Padova, Padova, Italy
- Science and Research Center Koper, Institute for Kinesiology Research, Koper, Slovenia
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Ponnusamy T, Velusamy P, Shanmughapriya S. Mrs2-mediated mitochondrial magnesium uptake is essential for the regulation of MCU-mediated mitochondrial Ca 2+ uptake and viability. Mitochondrion 2024; 76:101877. [PMID: 38599304 DOI: 10.1016/j.mito.2024.101877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 03/07/2024] [Accepted: 04/07/2024] [Indexed: 04/12/2024]
Abstract
Mitochondrial Ca2+ uptake is essential in regulating bioenergetics, cell death, and cytosolic Ca2+ transients. Mitochondrial Calcium Uniporter (MCU) mediates the mitochondrial Ca2+ uptake. Though MCU regulation by MICUs is unequivocally established, there needs to be more knowledge of whether divalent cations regulate MCU. Here, we set out to understand the mitochondrial matrix Mg2+-dependent regulation of MCU activity. We showed that decreased matrix [Mg2+] is associated with increased MCU activity and significantly prompted mitochondrial permeability transition pore opening. Our findings support the critical role of mMg2+ in regulating MCU activity.
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Affiliation(s)
- Thiruvelselvan Ponnusamy
- Heart and Vascular Institute, Department of Medicine, Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Prema Velusamy
- Heart and Vascular Institute, Department of Medicine, Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Santhanam Shanmughapriya
- Heart and Vascular Institute, Department of Medicine, Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA.
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Dominguez LJ, Veronese N, Barbagallo M. Magnesium and the Hallmarks of Aging. Nutrients 2024; 16:496. [PMID: 38398820 PMCID: PMC10892939 DOI: 10.3390/nu16040496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 02/01/2024] [Accepted: 02/05/2024] [Indexed: 02/25/2024] Open
Abstract
Magnesium is an essential ion in the human body that regulates numerous physiological and pathological processes. Magnesium deficiency is very common in old age. Age-related chronic diseases and the aging process itself are frequently associated with low-grade chronic inflammation, called 'inflammaging'. Because chronic magnesium insufficiency has been linked to excessive generation of inflammatory markers and free radicals, inducing a chronic inflammatory state, we formerly hypothesized that magnesium inadequacy may be considered among the intermediaries helping us explain the link between inflammaging and aging-associated diseases. We show in this review evidence of the relationship of magnesium with all the hallmarks of aging (genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, altered intercellular communication, disabled autophagy, dysbiosis, and chronic inflammation), which may positively affect the human healthspan. It is feasible to hypothesize that maintaining an optimal balance of magnesium during one's life course may turn out to be a safe and economical strategy contributing to the promotion of healthy aging. Future well-designed studies are necessary to further explore this hypothesis.
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Affiliation(s)
- Ligia J. Dominguez
- School of Medicine, “Kore” University of Enna, 94100 Enna, Italy;
- Geriatric Unit, Department of Medicine, University of Palermo, 90127 Palermo, Italy;
| | - Nicola Veronese
- Geriatric Unit, Department of Medicine, University of Palermo, 90127 Palermo, Italy;
| | - Mario Barbagallo
- Geriatric Unit, Department of Medicine, University of Palermo, 90127 Palermo, Italy;
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Ashique S, Kumar S, Hussain A, Mishra N, Garg A, Gowda BHJ, Farid A, Gupta G, Dua K, Taghizadeh-Hesary F. A narrative review on the role of magnesium in immune regulation, inflammation, infectious diseases, and cancer. JOURNAL OF HEALTH, POPULATION, AND NUTRITION 2023; 42:74. [PMID: 37501216 PMCID: PMC10375690 DOI: 10.1186/s41043-023-00423-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 07/24/2023] [Indexed: 07/29/2023]
Abstract
BACKGROUND Magnesium (Mg) has gained much importance recently because of its unique range of biological functions. It is one of the most significant micronutrients in biological systems. This review aims to outline the immune-regulating actions of Mg and its crucial role in regulating inflammation and immune response to infectious agents and malignancies. METHODS We conducted a literature review on MEDLINE, PubMed, EMBASE, Web of Science to determine the impact of Mg on immune regulation in three settings of inflammation, infection, and cancer. We thoroughly examined all abstracts and full-text articles and selected the most relevant ones for inclusion in this review. RESULTS Mg has long been associated with immunological responses, both nonspecific and specific. It plays a pivotal role in diverse immune responses by participating in multiple mechanisms. It facilitates substance P binding to lymphoblasts, promotes T helper, B cell, and macrophage responses to lymphokines, and facilitates antibody-dependent cytolysis and immune cell adherence. Besides, Mg serves as a cofactor for C'3 convertase and immunoglobulin synthesis. It additionally boasts a significant anti-cancer effect. Chronic Mg deficiency leads to enhanced baseline inflammation associated with oxidative stress, related to various age-associated morbidities. A deficiency of Mg in rodents has been observed to impact the cell-mediated immunity and synthesis of IgG adversely. This deficiency can lead to various complications, such as lymphoma, histaminosis, hypereosinophilia, increased levels of IgE, and atrophy of the thymus. The immunological consequences of Mg deficiency in humans can be influenced by the genetic regulation of Mg levels in blood cells. Mg can also mediate cell cycle progression. There has been a renewed interest in the physiology and therapeutic efficacy of Mg. However, the in-depth mechanisms, their clinical significance, and their importance in malignancies and inflammatory disorders still need to be clarified. CONCLUSIONS Mg is essential for optimal immune function and regulating inflammation. Deficiency in Mg can lead to temporary or long-term immune dysfunction. A balanced diet usually provides sufficient Mg, but supplementation may be necessary in some cases. Excessive supplementation can have negative impacts on immune function and should be avoided. This review provides an update on the importance of Mg in an immune response against cancer cells and infectious agents and how it regulates inflammation, oxidative stress, cell progression, differentiation, and apoptosis.
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Affiliation(s)
- Sumel Ashique
- Department of Pharmaceutics, Pandaveswar School of Pharmacy, Pandaveswar, West Bengal, 713378, India
| | - Shubneesh Kumar
- Department of Pharmaceutics, School of Pharmacy, Bharat Institute of Technology (BIT), Meerut, 250103, UP, India
| | - Afzal Hussain
- Department of Pharmaceutics, College of Pharmacy, King Saud University, 11451, Riyadh, Saudi Arabia
| | - Neeraj Mishra
- Department of Pharmaceutics, Amity Institute of Pharmacy, Amity University Madhya Pradesh (AUMP), Gwalior, MP, 474005, India
| | - Ashish Garg
- Department of Pharmaceutics, Guru Ramdas Khalsa Institute of Science and Technology (Pharmacy), Jabalpur, Madhya Pradesh, India
| | - B H Jaswanth Gowda
- Department of Pharmaceutics, Yenepoya Pharmacy College & Research Centre, Yenepoya (Deemed to Be University), Mangalore, 575018, India
| | - Arshad Farid
- Gomal Center of Biochemistry and Biotechnology, Gomal University, D.I.Khan, KPK, Pakistan
| | - Gaurav Gupta
- School of Pharmacy, Suresh Gyan Vihar University, Mahal Road, Jagatpura, Jaipur, India
| | - Kamal Dua
- Discipline of Pharmacy, Graduate School of Health, University of Technology Sydney, Ultimo, NSW, 2007, Australia
- Faculty of Health, Australian Research Centre in Complementary and Integrative Medicine, University of Technology Sydney, Ultimo, Australia
| | - Farzad Taghizadeh-Hesary
- ENT and Head and Neck Research Center and Department, The Five Senses Health Institute, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
- Department of Clinical Oncology, Iran University of Medical Sciences, Tehran, Iran.
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Ponnusamy T, Velusamy P, Kumar A, Morris D, Zhang X, Ning G, Klinger M, Copper JE, Rajan S, Cheung JY, Natarajaseenivasan K, Mnatsakanyan N, Shanmughapriya S. Mitochondrial Magnesium is the cationic rheostat for MCU-mediated mitochondrial Ca 2+ uptake. RESEARCH SQUARE 2023:rs.3.rs-3088175. [PMID: 37502932 PMCID: PMC10371168 DOI: 10.21203/rs.3.rs-3088175/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Calcium (Ca2+) uptake by mitochondria is essential in regulating bioenergetics, cell death, and cytosolic Ca2+ transients. Mitochondrial Calcium Uniporter (MCU) mediates the mitochondrial Ca2+ uptake. MCU is a heterooligomeric complex with a pore-forming component and accessory proteins required for channel activity. Though MCU regulation by MICUs is unequivocally established, there needs to be more knowledge of whether divalent cations regulate MCU. Here we set out to understand the mitochondrial matrix Mg2+-dependent regulation of MCU activity. We showed Mrs2 as the authentic mammalian mitochondrial Mg2+ channel using the planar lipid bilayer recordings. Using a liver-specific Mrs2 KO mouse model, we showed that decreased matrix [Mg2+] is associated with increased MCU activity and matrix Ca2+ overload. The disruption of Mg2+dependent MCU regulation significantly prompted mitochondrial permeability transition pore opening-mediated cell death during tissue IR injury. Our findings support a critical role for mMg2+ in regulating MCU activity and attenuating mCa2+ overload.
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Affiliation(s)
- Thiruvelselvan Ponnusamy
- Heart and Vascular Institute, Department of Medicine, Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Prema Velusamy
- Heart and Vascular Institute, Department of Medicine, Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Amrendra Kumar
- Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Daniel Morris
- Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Xueqian Zhang
- Cardiovascular Medicine, Department of Medicine, UMass Chan Medical School, Worcester, MA 01655, USA
| | - Gang Ning
- Microscopy Core Facility, Penn State Huck Institutes of the Life Sciences, University Park, PA 16802, USA
| | - Marianne Klinger
- Department of Pathology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Jean E. Copper
- Department of Pathology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Sudarsan Rajan
- Center for Translational Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA
| | - Joseph Y Cheung
- Department of Renal Medicine, Brigham & Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | | | - Nelli Mnatsakanyan
- Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Santhanam Shanmughapriya
- Heart and Vascular Institute, Department of Medicine, Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
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Hypothermia Prevents Cardiac Dysfunction during Acute Ischemia Reperfusion by Maintaining Mitochondrial Bioenergetics and by Promoting Hexokinase II Binding to Mitochondria. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:4476448. [PMID: 35873800 PMCID: PMC9301761 DOI: 10.1155/2022/4476448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 03/04/2022] [Accepted: 06/14/2022] [Indexed: 11/18/2022]
Abstract
Background Hypothermia (H), cardioplegia (CP), and both combined (HCP) are known to be protective against myocardial ischemia reperfusion (IR) injury. Mitochondria have molecular signaling mechanisms that are associated with both cell survival and cell death. In this study, we investigated the dynamic changes in proapoptotic and prosurvival signaling pathways mediating H, CP, or HCP-induced protection of mitochondrial function after acute myocardial IR injury. Methods Rats were divided into five groups. Each group consists of 3 subgroups based on a specific reperfusion time (5, 20, or 60 min) after a 25-min global ischemia. The time control (TC) groups were not subjected to IR but were perfused with 37 °C Krebs-Ringer's (KR) buffer, containing 4.5 mM K+, in a specific perfusion protocol that corresponded with the duration of each IR protocol. The IR group (control) was perfused for 20 min with KR, followed by 25-min global ischemia, and then KR reperfusion for 5, 20, or 60 min. The treatment groups were exposed to 17 °C H, 37 °C CP (16 mM K+), or HCP (17 °C + CP) for 5 min before ischemia and for 2 min on reperfusion before switching to 37 °C KR perfusion for the remainder of each of the reperfusion times. Cardiac function and mitochondrial redox state (NADH/FAD) were monitored online in the ex vivo hearts before, during, and after ischemia. Mitochondria were isolated at the end of each specified reperfusion time, and changes in O2 consumption, membrane potential (ΔΨm), and Ca2+ retention capacity (CRC) were assessed using complex I and complex II substrates. In another set of hearts, mitochondrial and cytosolic fractions were isolated after a specified reperfusion time to conduct western blot assays to determine hexokinase II (HKII) and Bax binding/translocation to mitochondria, cytosolic pAkt levels, and cytochrome c (Cyto-c) release into the cytosol. Results H and HCP were more protective of mitochondrial integrity and, concomitantly, cardiac function than CP alone; H and HCP improved post-ischemic cardiac function by (1) maintaining mitochondrial bioenergetics, (2) maintaining HKII binding to mitochondria with an increase in pAkt levels, (3) increasing CRC, and (4) decreasing Cyto-c release during reperfusion. Bax translocation/binding to mitochondria was unaffected by any treatment, regardless of cardiac functional recovery. Conclusions Hypothermia preserved mitochondrial function and cardiac function, in part, by maintaining mitochondrial bioenergetics, by retaining HKII binding to mitochondria via upstream pAkt, and by reducing Cyto-c release independently of Bax binding to mitochondria.
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Garbincius JF, Elrod JW. Mitochondrial calcium exchange in physiology and disease. Physiol Rev 2022; 102:893-992. [PMID: 34698550 PMCID: PMC8816638 DOI: 10.1152/physrev.00041.2020] [Citation(s) in RCA: 136] [Impact Index Per Article: 68.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 08/16/2021] [Accepted: 10/19/2021] [Indexed: 12/13/2022] Open
Abstract
The uptake of calcium into and extrusion of calcium from the mitochondrial matrix is a fundamental biological process that has critical effects on cellular metabolism, signaling, and survival. Disruption of mitochondrial calcium (mCa2+) cycling is implicated in numerous acquired diseases such as heart failure, stroke, neurodegeneration, diabetes, and cancer and is genetically linked to several inherited neuromuscular disorders. Understanding the mechanisms responsible for mCa2+ exchange therefore holds great promise for the treatment of these diseases. The past decade has seen the genetic identification of many of the key proteins that mediate mitochondrial calcium uptake and efflux. Here, we present an overview of the phenomenon of mCa2+ transport and a comprehensive examination of the molecular machinery that mediates calcium flux across the inner mitochondrial membrane: the mitochondrial uniporter complex (consisting of MCU, EMRE, MICU1, MICU2, MICU3, MCUB, and MCUR1), NCLX, LETM1, the mitochondrial ryanodine receptor, and the mitochondrial permeability transition pore. We then consider the physiological implications of mCa2+ flux and evaluate how alterations in mCa2+ homeostasis contribute to human disease. This review concludes by highlighting opportunities and challenges for therapeutic intervention in pathologies characterized by aberrant mCa2+ handling and by summarizing critical unanswered questions regarding the biology of mCa2+ flux.
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Affiliation(s)
- Joanne F Garbincius
- Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania
| | - John W Elrod
- Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania
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Rapid Treatment with Intramuscular Magnesium Sulfate During Cardiopulmonary Resuscitation Does Not Provide Neuroprotection Following Cardiac Arrest. Mol Neurobiol 2022; 59:1872-1881. [PMID: 35028899 DOI: 10.1007/s12035-021-02645-x] [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: 08/27/2021] [Accepted: 11/11/2021] [Indexed: 10/19/2022]
Abstract
Brain injury is the most common cause of death for patients resuscitated from cardiac arrest. Magnesium is an attractive neuroprotective compound which protects neurons from ischemic injury by reducing neuronal calcium overload via NMDA receptor modulation and preventing calcium-induced mitochondrial permeability transition. Intramuscular (IM) delivery of MgSO4 during CPR has the potential to target these mechanisms within an early therapeutic window. We hypothesize that IM MgSO4 administrated during CPR could achieve therapeutic serum magnesium levels within 15 min after ROSC and improve neurologic outcomes in a rat model of asphyxial cardiac arrest. Male Long Evans rats were subjected to 8-min asphyxial cardiac arrest and block randomized to receive placebo, 107 mg/kg, 215 mg/kg, or 430 mg/kg MgSO4 IM at the onset of CPR. Serum magnesium concentrations increased rapidly with IM delivery during CPR, achieving twofold to fourfold increase by 15 min after ROSC in all magnesium dose groups. Rats subjected to cardiac arrest or sham surgery were block randomized to treatment groups for assessment of neurological outcomes. We found that IM MgSO4 during CPR had no effect on ROSC rate (p > 0.05). IM MgSO4 treatment had no statistically significant effect on 10-day survival with good neurologic function or hippocampal CA1 pyramidal neuron survival compared to placebo treatment. In conclusion, a single dose IM MgSO4 during CPR achieves up to fourfold baseline serum magnesium levels within 15 min after ROSC; however, this treatment strategy did not improve survival, recovery of neurologic function, or neuron survival. Future studies with repeated dosing or in combination with hypothermic targeted temperature management may be indicated.
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Zhang X, Tomar N, Kandel SM, Audi SH, Cowley AW, Dash RK. Substrate- and Calcium-Dependent Differential Regulation of Mitochondrial Oxidative Phosphorylation and Energy Production in the Heart and Kidney. Cells 2021; 11:131. [PMID: 35011693 PMCID: PMC8750792 DOI: 10.3390/cells11010131] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 12/26/2021] [Accepted: 12/28/2021] [Indexed: 11/16/2022] Open
Abstract
Mitochondrial dehydrogenases are differentially stimulated by Ca2+. Ca2+ has also diverse regulatory effects on mitochondrial transporters and other enzymes. However, the consequences of these regulatory effects on mitochondrial oxidative phosphorylation (OxPhos) and ATP production, and the dependencies of these consequences on respiratory substrates, have not been investigated between the kidney and heart despite the fact that kidney energy requirements are second only to those of the heart. Our objective was, therefore, to elucidate these relationships in isolated mitochondria from the kidney outer medulla (OM) and heart. ADP-induced mitochondrial respiration was measured at different CaCl2 concentrations in the presence of various respiratory substrates, including pyruvate + malate (PM), glutamate + malate (GM), alpha-ketoglutarate + malate (AM), palmitoyl-carnitine + malate (PCM), and succinate + rotenone (SUC + ROT). The results showed that, in both heart and OM mitochondria, and for most complex I substrates, Ca2+ effects are biphasic: small increases in Ca2+ concentration stimulated, while large increases inhibited mitochondrial respiration. Furthermore, significant differences in substrate- and Ca2+-dependent O2 utilization towards ATP production between heart and OM mitochondria were observed. With PM and PCM substrates, Ca2+ showed more prominent stimulatory effects in OM than in heart mitochondria, while with GM and AM substrates, Ca2+ had similar biphasic regulatory effects in both OM and heart mitochondria. In contrast, with complex II substrate SUC + ROT, only inhibitory effects on mitochondrial respiration was observed in both the heart and the OM. We conclude that the regulatory effects of Ca2+ on mitochondrial OxPhos and ATP synthesis are biphasic, substrate-dependent, and tissue-specific.
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Affiliation(s)
- Xiao Zhang
- Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, WI 53226, USA; (X.Z.); (N.T.); (S.M.K.)
| | - Namrata Tomar
- Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, WI 53226, USA; (X.Z.); (N.T.); (S.M.K.)
| | - Sunil M. Kandel
- Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, WI 53226, USA; (X.Z.); (N.T.); (S.M.K.)
| | - Said H. Audi
- Department of Biomedical Engineering, Marquette University, Milwaukee, WI 53223, USA;
| | - Allen W. Cowley
- Center of Systems Molecular Medicine, Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Ranjan K. Dash
- Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, WI 53226, USA; (X.Z.); (N.T.); (S.M.K.)
- Center of Systems Molecular Medicine, Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
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Dominguez LJ, Veronese N, Guerrero-Romero F, Barbagallo M. Magnesium in Infectious Diseases in Older People. Nutrients 2021; 13:E180. [PMID: 33435521 PMCID: PMC7827130 DOI: 10.3390/nu13010180] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 12/30/2020] [Accepted: 01/04/2021] [Indexed: 12/14/2022] Open
Abstract
Reduced magnesium (Mg) intake is a frequent cause of deficiency with age together with reduced absorption, renal wasting, and polypharmacotherapy. Chronic Mg deficiency may result in increased oxidative stress and low-grade inflammation, which may be linked to several age-related diseases, including higher predisposition to infectious diseases. Mg might play a role in the immune response being a cofactor for immunoglobulin synthesis and other processes strictly associated with the function of T and B cells. Mg is necessary for the biosynthesis, transport, and activation of vitamin D, another key factor in the pathogenesis of infectious diseases. The regulation of cytosolic free Mg in immune cells involves Mg transport systems, such as the melastatin-like transient receptor potential 7 channel, the solute carrier family, and the magnesium transporter 1 (MAGT1). The functional importance of Mg transport in immunity was unknown until the description of the primary immunodeficiency XMEN (X-linked immunodeficiency with Mg defect, Epstein-Barr virus infection, and neoplasia) due to a genetic deficiency of MAGT1 characterized by chronic Epstein-Barr virus infection. This and other research reporting associations of Mg deficit with viral and bacterial infections indicate a possible role of Mg deficit in the recent coronavirus disease 2019 (COVID-19) and its complications. In this review, we will discuss the importance of Mg for the immune system and for infectious diseases, including the recent pandemic of COVID-19.
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Affiliation(s)
- Ligia J. Dominguez
- Geriatric Unit, Department of Internal Medicine and Geriatrics, University of Palermo, 90100 Palermo, Italy; (L.J.D.); (M.B.)
| | - Nicola Veronese
- Geriatric Unit, Department of Internal Medicine and Geriatrics, University of Palermo, 90100 Palermo, Italy; (L.J.D.); (M.B.)
| | | | - Mario Barbagallo
- Geriatric Unit, Department of Internal Medicine and Geriatrics, University of Palermo, 90100 Palermo, Italy; (L.J.D.); (M.B.)
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Mitochondrial osmoregulation in evolution, cation transport and metabolism. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2021; 1862:148368. [PMID: 33422486 DOI: 10.1016/j.bbabio.2021.148368] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 12/22/2020] [Accepted: 01/04/2021] [Indexed: 11/24/2022]
Abstract
This review provides a retrospective on the role of osmotic regulation in the process of eukaryogenesis. Specifically, it focuses on the adjustments which must have been made by the original colonizing α-proteobacteria that led to the evolution of modern mitochondria. We focus on the cations that are fundamentally involved in volume determination and cellular metabolism and define the transporter landscape in relation to these ions in mitochondria as we know today. We provide analysis on how the cations interplay and together maintain osmotic balance that allows for effective ATP synthesis in the organelle.
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12
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Dominguez LJ, Veronese N, Barbagallo M. Magnesium and Hypertension in Old Age. Nutrients 2020; 13:E139. [PMID: 33396570 PMCID: PMC7823889 DOI: 10.3390/nu13010139] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/27/2020] [Accepted: 12/29/2020] [Indexed: 12/15/2022] Open
Abstract
Hypertension is a complex condition in which various actors and mechanisms combine, resulting in cardiovascular and cerebrovascular complications that today represent the most frequent causes of mortality, morbidity, disability, and health expenses worldwide. In recent decades, there has been an exceptional number of experimental, epidemiological, and clinical studies confirming a close relationship between magnesium deficit and high blood pressure. Multiple mechanisms may help to explain the bulk of evidence supporting a protective effect of magnesium against hypertension and its complications. Hypertension increases sharply with advancing age, hence older persons are those most affected by its negative consequences. They are also more frequently at risk of magnesium deficiency by multiple mechanisms, which may, at least in part, explain the higher frequency of hypertension and its long-term complications. The evidence for a favorable effect of magnesium on hypertension risk emphasizes the importance of broadly encouraging the intake of foods such as vegetables, nuts, whole cereals and legumes, optimal dietary sources of magnesium, and avoiding processed foods, which are very poor in magnesium and other fundamental nutrients, in order to prevent hypertension. In some cases, when diet is not enough to maintain an adequate magnesium status, magnesium supplementation may be of benefit and has been shown to be well tolerated.
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Affiliation(s)
| | | | - Mario Barbagallo
- Geriatric Unit, Department of Medicine, University of Palermo, 90100 Palermo, Italy; (L.J.D.); (N.V.)
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13
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Liu M, Dudley SC. Magnesium, Oxidative Stress, Inflammation, and Cardiovascular Disease. Antioxidants (Basel) 2020; 9:E907. [PMID: 32977544 PMCID: PMC7598282 DOI: 10.3390/antiox9100907] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 12/15/2022] Open
Abstract
Hypomagnesemia is commonly observed in heart failure, diabetes mellitus, hypertension, and cardiovascular diseases. Low serum magnesium (Mg) is a predictor for cardiovascular and all-cause mortality and treating Mg deficiency may help prevent cardiovascular disease. In this review, we discuss the possible mechanisms by which Mg deficiency plays detrimental roles in cardiovascular diseases and review the results of clinical trials of Mg supplementation for heart failure, arrhythmias and other cardiovascular diseases.
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Affiliation(s)
- Man Liu
- Division of Cardiology, Department of Medicine, the Lillehei Heart Institute, University of Minnesota at Twin Cities, Minneapolis, MN 55455, USA
| | - Samuel C. Dudley
- Division of Cardiology, Department of Medicine, the Lillehei Heart Institute, University of Minnesota at Twin Cities, Minneapolis, MN 55455, USA
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14
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Natarajan GK, Glait L, Mishra J, Stowe DF, Camara AKS, Kwok WM. Total Matrix Ca 2+ Modulates Ca 2+ Efflux via the Ca 2+/H + Exchanger in Cardiac Mitochondria. Front Physiol 2020; 11:510600. [PMID: 33041851 PMCID: PMC7526510 DOI: 10.3389/fphys.2020.510600] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 08/13/2020] [Indexed: 12/12/2022] Open
Abstract
Mitochondrial Ca2+ handling is accomplished by balancing Ca2+ uptake, primarily via the Ru360-sensitive mitochondrial calcium uniporter (MCU), Ca2+ buffering in the matrix and Ca2+ efflux mainly via Ca2+ ion exchangers, such as the Na+/Ca2+ exchanger (NCLX) and the Ca2+/H+ exchanger (CHE). The mechanism of CHE in cardiac mitochondria is not well-understood and its contribution to matrix Ca2+ regulation is thought to be negligible, despite higher expression of the putative CHE protein, LETM1, compared to hepatic mitochondria. In this study, Ca2+ efflux via the CHE was investigated in isolated rat cardiac mitochondria and permeabilized H9c2 cells. Mitochondria were exposed to (a) increasing matrix Ca2+ load via repetitive application of a finite CaCl2 bolus to the external medium and (b) change in the pH gradient across the inner mitochondrial membrane (IMM). Ca2+ efflux at different matrix Ca2+ loads was revealed by inhibiting Ca2+ uptake or reuptake with Ru360 after increasing number of CaCl2 boluses. In Na+-free experimental buffer and with Ca2+ uptake inhibited, the rate of Ca2+ efflux and steady-state free matrix Ca2+ [mCa2+]ss increased as the number of administered CaCl2 boluses increased. ADP and cyclosporine A (CsA), which are known to increase Ca2+ buffering while maintaining a constant [mCa2+]ss, decreased the rate of Ca2+ efflux via the CHE, with a significantly greater decrease in the presence of ADP. ADP also increased Ca2+ buffering rate and decreased [mCa2+]ss. A change in the pH of the external medium to a more acidic value from 7.15 to 6.8∼6.9 caused a twofold increase in the Ca2+ efflux rate, while an alkaline change in pH from 7.15 to 7.4∼7.5 did not change the Ca2+ efflux rate. In addition, CHE activation was associated with membrane depolarization. Targeted transient knockdown of LETM1 in permeabilized H9c2 cells modulated Ca2+ efflux. The results indicate that Ca2+ efflux via the CHE in cardiac mitochondria is modulated by acidic buffer pH and by total matrix Ca2+. A mechanism is proposed whereby activation of CHE is sensitive to changes in both the matrix Ca2+ buffering system and the matrix free Ca2+ concentration.
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Affiliation(s)
- Gayathri K Natarajan
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Lyall Glait
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Jyotsna Mishra
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - David F Stowe
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, United States.,Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States.,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, United States.,Department of Biomedical Engineering, Medical College of Wisconsin and Marquette University, Milwaukee, WI, United States.,Research Service, Veteran Affairs Medical Center, Milwaukee, WI, United States
| | - Amadou K S Camara
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, United States.,Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States.,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, United States.,Cancer Center, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Wai-Meng Kwok
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, United States.,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, United States.,Cancer Center, Medical College of Wisconsin, Milwaukee, WI, United States.,Department of Pharmacology & Toxicology, Medical College of Wisconsin, Milwaukee, WI, United States
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15
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Gerdes HJ, Yang M, Heisner JS, Camara AKS, Stowe DF. Modulation of peroxynitrite produced via mitochondrial nitric oxide synthesis during Ca 2+ and succinate-induced oxidative stress in cardiac isolated mitochondria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1861:148290. [PMID: 32828729 DOI: 10.1016/j.bbabio.2020.148290] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 07/23/2020] [Accepted: 07/29/2020] [Indexed: 01/09/2023]
Abstract
We hypothesized that NO• is generated in isolated cardiac mitochondria as the source for ONOO- production during oxidative stress. We monitored generation of ONOO- from guinea pig isolated cardiac mitochondria subjected to excess Ca2+ uptake before adding succinate and determined if ONOO- production was dependent on a nitric oxide synthase (NOS) located in cardiac mitochondria (mtNOS). Mitochondria were suspended in experimental buffer at pH 7.15, and treated with CaCl2 and then the complex II substrate Na-succinate, followed by menadione, a quinone redox cycler, to generate O2•-. L-tyrosine was added to the mitochondrial suspension where it is oxidized by ONOO- to form dityrosine (diTyr) in proportion to the ONOO- present. We found that exposing mitochondria to excess CaCl2 before succinate resulted in an increase in diTyr and amplex red fluorescence (H2O2) signals, indicating that mitochondrial oxidant stress, induced by elevated mtCa2+ and succinate, increased mitochondrial ONOO- production via NO• and O2•-. Changes in mitochondrial ONOO- production dependent on NOS were evidenced by using NOS inhibitors L-NAME/L-NNA, TEMPOL, a superoxide dismutase (SOD) mimetic, and PTIO, a potent global NO• scavenger. L-NAME and L-NNA decreased succinate and menadione-mediated ONOO- production, PTIO decreased production of ONOO-, and TEMPOL decreased ONOO- levels by converting more O2•- to H2O2. Electron microscopy showed immuno-gold labeled iNOS and nNOS in mitochondria isolated from cardiomyocytes and heart tissue. Western blots demonstrated iNOS and nNOS bands in total heart tissue, bands for both iNOS and nNOS in β-tubulin-free non-purified (crude) mitochondrial preparations, and a prominent iNOS band, but no nNOS band, in purified (Golgi and ER-free) mitochondria. Prior treatment of guinea pigs with lipopolysacharride (LPS) enhanced expression of iNOS in liver mitochondria but not in heart mitochondria. Our results indicate that release of ONOO- into the buffer is dependent both on O2•- released from mitochondria and NO• derived from a mtCa2+-inducible nNOS isoform, possibly attached to mitochondria, and a mtNOS isoform like iNOS that is non-inducible.
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Affiliation(s)
- Harrison J Gerdes
- Anesthesiology Research Division, Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Meiying Yang
- Anesthesiology Research Division, Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - James S Heisner
- Anesthesiology Research Division, Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Amadou K S Camara
- Anesthesiology Research Division, Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA; Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, USA; Cancer Center, Medical College of Wisconsin, Milwaukee, WI, USA
| | - David F Stowe
- Anesthesiology Research Division, Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA; Cancer Center, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Biomedical Engineering, Medical College of Wisconsin and Marquette University, Milwaukee, WI, USA; Research Service, Zablocki Veterans Affairs Medical Center, Milwaukee, WI, USA.
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16
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Cyclosporin A Increases Mitochondrial Buffering of Calcium: An Additional Mechanism in Delaying Mitochondrial Permeability Transition Pore Opening. Cells 2019; 8:cells8091052. [PMID: 31500337 PMCID: PMC6770067 DOI: 10.3390/cells8091052] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Revised: 08/26/2019] [Accepted: 09/03/2019] [Indexed: 02/07/2023] Open
Abstract
Regulation of mitochondrial free Ca2+ is critically important for cellular homeostasis. An increase in mitochondrial matrix free Ca2+ concentration ([Ca2+]m) predisposes mitochondria to opening of the permeability transition pore (mPTP). Opening of the pore can be delayed by cyclosporin A (CsA), possibly by inhibiting cyclophilin D (Cyp D), a key regulator of mPTP. Here, we report on a novel mechanism by which CsA delays mPTP opening by enhanced sequestration of matrix free Ca2+. Cardiac-isolated mitochondria were challenged with repetitive CaCl2 boluses under Na+-free buffer conditions with and without CsA. CsA significantly delayed mPTP opening primarily by promoting matrix Ca2+ sequestration, leading to sustained basal [Ca2+]m levels for an extended period. The preservation of basal [Ca2+]m during the CaCl2 pulse challenge was associated with normalized NADH, matrix pH (pHm), and mitochondrial membrane potential (ΔΨm). Notably, we found that in PO43− (Pi)-free buffer condition, the CsA-mediated buffering of [Ca2+]m was abrogated, and mitochondrial bioenergetics variables were concurrently compromised. In the presence of CsA, addition of Pi just before pore opening in the Pi-depleted condition reinstated the Ca2+ buffering system and rescued mitochondria from mPTP opening. This study shows that CsA promotes Pi-dependent mitochondrial Ca2+ sequestration to delay mPTP opening and, concomitantly, maintains mitochondrial function.
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17
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Malyala S, Zhang Y, Strubbe JO, Bazil JN. Calcium phosphate precipitation inhibits mitochondrial energy metabolism. PLoS Comput Biol 2019; 15:e1006719. [PMID: 30615608 PMCID: PMC6336351 DOI: 10.1371/journal.pcbi.1006719] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Revised: 01/17/2019] [Accepted: 12/17/2018] [Indexed: 11/19/2022] Open
Abstract
Early studies have shown that moderate levels of calcium overload can cause lower oxidative phosphorylation rates. However, the mechanistic interpretations of these findings were inadequate. And while the effect of excessive calcium overload on mitochondrial function is well appreciated, there has been little to no reports on the consequences of low to moderate calcium overload. To resolve this inadequacy, mitochondrial function from guinea pig hearts was quantified using several well-established methods including high-resolution respirometry and spectrofluorimetry and analyzed using mathematical modeling. We measured key mitochondrial variables such as respiration, mitochondrial membrane potential, buffer calcium, and substrate effects for a range of mitochondrial calcium loads from near zero to levels approaching mitochondrial permeability transition. In addition, we developed a computer model closely mimicking the experimental conditions and used this model to design experiments capable of eliminating many hypotheses generated from the data analysis. We subsequently performed those experiments and determined why mitochondrial ADP-stimulated respiration is significantly lowered during calcium overload. We found that when calcium phosphate levels, not matrix free calcium, reached sufficient levels, complex I activity is inhibited, and the rate of ATP synthesis is reduced. Our findings suggest that calcium phosphate granules form physical barriers that isolate complex I from NADH, disrupt complex I activity, or destabilize cristae and inhibit NADH-dependent respiration. Mitochondrial calcium handling has been studied for nearly half a century. As we understand it today, low concentrations (1–10 nmol/mg mitochondria) of calcium exert beneficial effects on energy transduction. And high concentrations (>500 nmol/mg mitochondria) lead to respiratory uncoupling and membrane damage. But relatively little is known about the effect of moderate calcium concentrations (10–500 nmol/mg mitochondria) on mitochondrial function. At these concentrations, mitochondrial membrane integrity remains intact and energized, while ATP synthesis becomes significantly impaired. Prior studies have postulated several possible mechanisms, but the precise consequence of calcium overload on mitochondrial ATP production remained obscure. In this study, we combine experimental and computational approaches to show that calcium phosphate precipitation, as opposed to matrix free calcium, inhibits respiratory function at complex I just enough to limit proton pumping during oxidative phosphorylation and decrease ATP synthesis rates.
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Affiliation(s)
- Sathyavani Malyala
- Department of Physiology, Michigan State University, East Lansing, MI, United States of America
| | - Yizhu Zhang
- Department of Physiology, Michigan State University, East Lansing, MI, United States of America
| | - Jasiel O. Strubbe
- Department of Physiology, Michigan State University, East Lansing, MI, United States of America
| | - Jason N. Bazil
- Department of Physiology, Michigan State University, East Lansing, MI, United States of America
- * E-mail:
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18
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Yang M, Xu Y, Heisner JS, Sun J, Stowe DF, Kwok WM, Camara AKS. Peroxynitrite nitrates adenine nucleotide translocase and voltage-dependent anion channel 1 and alters their interactions and association with hexokinase II in mitochondria. Mitochondrion 2018; 46:380-392. [PMID: 30391711 DOI: 10.1016/j.mito.2018.10.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 09/26/2018] [Accepted: 10/22/2018] [Indexed: 12/17/2022]
Abstract
Cardiac ischemia and reperfusion (IR) injury induces excessive emission of deleterious reactive O2 and N2 species (ROS/RNS), including the non-radical oxidant peroxynitrite (ONOO-) that can cause mitochondria dysfunction and cell death. In this study, we explored whether IR injury in isolated hearts induces tyrosine nitration of adenine nucleotide translocase (ANT) and alters its interaction with the voltage-dependent anion channel 1 (VDAC1). We found that IR injury induced tyrosine nitration of ANT and that exposure of isolated cardiac mitochondria to ONOO- induced ANT tyrosine, Y81, nitration. The exposure of isolated cardiac mitochondria to ONOO- also led ANT to form high molecular weight proteins and dissociation of ANT from VDAC1. We found that IR injury in isolated hearts, hypoxic injury in H9c2 cells, and ONOO- treatment of H9c2 cells and isolated mitochondria, each decreased mitochondrial bound-hexokinase II (HK II), which suggests that ONOO- caused HK II to dissociate from mitochondria. Moreover, we found that mitochondria exposed to ONOO- induced VDAC1 oligomerization which may decrease its binding with HK II. We have reported that ONOO- produced during cardiac IR injury induced tyrosine nitration of VDAC1, which resulted in conformational changes of the protein and increased channel conductance associated with compromised cardiac function on reperfusion. Thus, our results imply that ONOO- produced during IR injury and hypoxic stress impeded HK II association with VDAC1. ONOO- exposure nitrated mitochondrial proteins and also led to cytochrome c (cyt c) release from mitochondria. In addition, in isolated mitochondria exposed to ONOO- or obtained after IR, there was significant compromise in mitochondrial respiration and delayed repolarization of membrane potential during oxidative (ADP) phosphorylation. Taken together, ONOO- produced during cardiac IR injury can nitrate tyrosine residues of two key mitochondrial membrane proteins involved in bioenergetics and energy transfer to contribute to mitochondrial and cellular dysfunction.
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Affiliation(s)
- Meiying Yang
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Yanji Xu
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Preventive Medicine, Medical College of Yanbian University, Yanji, Jilin, China
| | - James S Heisner
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Jie Sun
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA; Institute of Clinical Medicine Research, Suzhou Hospital affiliated with Nanjing Medical University, Suzhou, Jiangsu, China; Department of Gastroenterology and Hepatology, Suzhou Hospital affiliated with Nanjing Medical University, Suzhou, Jiangsu, China
| | - David F Stowe
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Biomedical Engineering, Medical College of Wisconsin and Marquette University, Milwaukee, WI, USA; Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA; Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, USA; Research Service, Zablocki VA Medical Center, Milwaukee, WI, USA
| | - Wai-Meng Kwok
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, USA; Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, USA; Cancer Center, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Amadou K S Camara
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA; Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, USA; Cancer Center, Medical College of Wisconsin, Milwaukee, WI, USA.
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19
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Austin S, Tavakoli M, Pfeiffer C, Seifert J, Mattarei A, De Stefani D, Zoratti M, Nowikovsky K. LETM1-Mediated K + and Na + Homeostasis Regulates Mitochondrial Ca 2+ Efflux. Front Physiol 2017; 8:839. [PMID: 29204122 PMCID: PMC5698270 DOI: 10.3389/fphys.2017.00839] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 10/09/2017] [Indexed: 12/13/2022] Open
Abstract
Ca2+ transport across the inner membrane of mitochondria (IMM) is of major importance for their functions in bioenergetics, cell death and signaling. It is therefore tightly regulated. It has been recently proposed that LETM1—an IMM protein with a crucial role in mitochondrial K+/H+ exchange and volume homeostasis—also acts as a Ca2+/H+ exchanger. Here we show for the first time that lowering LETM1 gene expression by shRNA hampers mitochondrial K+/H+ and Na+/H+ exchange. Decreased exchange activity resulted in matrix K+ accumulation in these mitochondria. Furthermore, LETM1 depletion selectively decreased Na+/Ca2+ exchange mediated by NCLX, as observed in the presence of ruthenium red, a blocker of the Mitochondrial Ca2+ Uniporter (MCU). These data confirm a key role of LETM1 in monovalent cation homeostasis, and suggest that the effects of its modulation on mitochondrial transmembrane Ca2+ fluxes may reflect those on Na+/H+ exchange activity.
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Affiliation(s)
- Shane Austin
- Department of Internal Medicine I and Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Mojtaba Tavakoli
- Department of Internal Medicine I and Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Christina Pfeiffer
- Department of Internal Medicine I and Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Julia Seifert
- Department of Internal Medicine I and Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Andrea Mattarei
- Department of Chemical Sciences, Università di Padova, Padova, Italy
| | - Diego De Stefani
- Department of Biomedical Sciences, Università di Padova, Padova, Italy
| | - Mario Zoratti
- Department of Biomedical Sciences, Università di Padova, Padova, Italy.,Institute of Neuroscience (CNR), Padova, Italy
| | - Karin Nowikovsky
- Department of Internal Medicine I and Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
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20
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Wollenman LC, Vander Ploeg MR, Miller ML, Zhang Y, Bazil JN. The effect of respiration buffer composition on mitochondrial metabolism and function. PLoS One 2017; 12:e0187523. [PMID: 29091971 PMCID: PMC5665555 DOI: 10.1371/journal.pone.0187523] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 10/20/2017] [Indexed: 11/19/2022] Open
Abstract
Functional studies on isolated mitochondria critically rely on the right choice of respiration buffer. Differences in buffer composition can lead to dramatically different respiration rates leading to difficulties in comparing prior studies. The ideal buffer facilities high ADP-stimulated respiratory rates and minimizes substrate transport effects so that the ability to distinguish between various treatments and conditions is maximal. In this study, we analyzed a variety of respiration buffers and substrate combinations to determine the optimal conditions to support mitochondrial function through ADP-stimulated respiration and uncoupled respiration using FCCP. The buffers consisted of a standard KCl based buffer (B1) and three modified buffers with chloride replaced by the K-lactobionate, sucrose, and the antioxidant taurine (B2) or K-gluconate (B3). The fourth buffer (B4) was identical to B2 except that K-lactobionate was replaced with K-gluconate. The substrate combinations consisted of metabolites that utilize different pathways of mitochondrial metabolism. To test mitochondrial function, we used isolated cardiac guinea pig mitochondria and measured oxygen consumption for three respiratory states using an Oroboros Oxygraph-2k. These states were the leak state (energized mitochondria in the absence of adenylates), ADP-stimulated state (energized mitochondria in the presence of saturating ADP concentrations), and uncoupled state (energized mitochondria in the presence of FCCP). On average across all substrate combinations, buffers B2, B3, and B4 had an increase of 16%, 26%, and 35% for the leak state, ADP-simulated state, and uncoupled state, respectively, relative to rates using B1. The common feature distinguishing these buffers from B1 is the notable lack of high chloride concentrations. Based on the respiratory rate metrics obtained with the substrate combinations, we conclude that the adenine nucleotide translocase, the dicarboxylate carrier, and the alpha-ketoglutarate exchanger are partially inhibited by chloride. Therefore, when the goal is to maximize ADP-stimulated respiration, buffers containing K-lactobionate or K-gluconate are superior choices compared to the standard KCl-based buffers.
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Affiliation(s)
- Lucas C. Wollenman
- Department of Physiology, Michigan State University, East Lansing, MI, United States of America
- Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Matthew R. Vander Ploeg
- Department of Physiology, Michigan State University, East Lansing, MI, United States of America
| | - Mackinzie L. Miller
- Biomedical Laboratory Diagnostics, Michigan State University, East Lansing, MI, United States of America
- Nephrology and Hypertension, Henry Ford Hospital, Detroit, MI, United States of America
| | - Yizhu Zhang
- Department of Physiology, Michigan State University, East Lansing, MI, United States of America
| | - Jason N. Bazil
- Department of Physiology, Michigan State University, East Lansing, MI, United States of America
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21
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Stowe DF, Yang M, Heisner JS, Camara AK. Endogenous and Agonist-induced Opening of Mitochondrial Big Versus Small Ca2+-sensitive K+ Channels on Cardiac Cell and Mitochondrial Protection. J Cardiovasc Pharmacol 2017; 70:314-328. [PMID: 28777255 PMCID: PMC5726766 DOI: 10.1097/fjc.0000000000000524] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Both big (BKCa) and small (SKCa) conductance Ca-sensitive K channels are present in mammalian cardiac cell mitochondria (m). We used pharmacological agonists and antagonists of BKCa and SKCa channels to examine the importance of endogenous opening of these channels and the relative contribution of either or both of these channels to protect against contractile dysfunction and reduce infarct size after ischemia reperfusion (IR) injury through a mitochondrial protective mechanism. After global cardiac IR injury of ex vivo perfused Guinea pig hearts, we found the following: both agonists NS1619 (for BKCa) and DCEB (for SKCa) improved contractility; BKCa antagonist paxilline (PAX) alone or with SKCa antagonist NS8593 worsened contractility and enhanced infarct size; both antagonists PAX and NS8593 obliterated protection by their respective agonists; BKCa and SKCa antagonists did not block protection afforded by SKCa and BKCa agonists, respectively; and all protective effects by the agonists were blocked by scavenging superoxide anions (O2) with Mn(III) tetrakis (4-benzoic acid) porphyrin (TBAP). Contractile function was inversely associated with global infarct size. In in vivo rats, infusion of NS8593, PAX, or both antagonists enhanced regional infarct size while infusion of either NS1619 or DCEB reduced infarct size. In cardiac mitochondria isolated from ex vivo hearts after IR, combined SKCa and BKCa agonists improved respiratory control index and Ca retention capacity compared with IR alone, whereas the combined antagonists did not alter respiratory control index but worsened Ca retention capacity. Although the differential protective bioenergetics effects of endogenous or exogenous BKCa and SKCa channel opening remain unclear, each channel likely responds to different sensing Ca concentrations and voltage gradients over time during oxidative stress-induced injury to individually or together protect cardiac mitochondria and myocytes.
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Affiliation(s)
- David F. Stowe
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA
- Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, WI, USA
- Cardiovascular Center, The Medical College of Wisconsin, Milwaukee, WI, USA
- Research Service, Zablocki VA Medical Center, Milwaukee, WI, USA
| | - Meiying Yang
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - James S. Heisner
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Amadou K.S. Camara
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
- Cardiovascular Center, The Medical College of Wisconsin, Milwaukee, WI, USA
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22
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Javadov S, Chapa-Dubocq X, Makarov V. Different approaches to modeling analysis of mitochondrial swelling. Mitochondrion 2017; 38:58-70. [PMID: 28802667 DOI: 10.1016/j.mito.2017.08.004] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 07/21/2017] [Accepted: 08/08/2017] [Indexed: 12/11/2022]
Abstract
Mitochondria are critical players involved in both cell life and death through multiple pathways. Structural integrity, metabolism and function of mitochondria are regulated by matrix volume due to physiological changes of ion homeostasis in cellular cytoplasm and mitochondria. Ca2+ and K+ presumably play a critical role in physiological and pathological swelling of mitochondria when increased uptake (influx)/decreased release (efflux) of these ions enhances osmotic pressure accompanied by high water accumulation in the matrix. Changes in the matrix volume in the physiological range have a stimulatory effect on electron transfer chain and oxidative phosphorylation to satisfy metabolic requirements of the cell. However, excessive matrix swelling associated with the sustained opening of mitochondrial permeability transition pores (PTP) and other PTP-independent mechanisms compromises mitochondrial function and integrity leading to cell death. The mechanisms of transition from reversible (physiological) to irreversible (pathological) swelling of mitochondria remain unknown. Mitochondrial swelling is involved in the pathogenesis of many human diseases such as neurodegenerative and cardiovascular diseases. Therefore, modeling analysis of the swelling process is important for understanding the mechanisms of cell dysfunction. This review attempts to describe the role of mitochondrial swelling in cell life and death and the main mechanisms involved in the maintenance of ion homeostasis and swelling. The review also summarizes and discusses different kinetic models and approaches that can be useful for the development of new models for better simulation and prediction of in vivo mitochondrial swelling.
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Affiliation(s)
- Sabzali Javadov
- Department of Physiology, School of Medicine, University of Puerto Rico, San Juan, PR, USA.
| | - Xavier Chapa-Dubocq
- Department of Physiology, School of Medicine, University of Puerto Rico, San Juan, PR, USA
| | - Vladimir Makarov
- Department of Physics, Rio Piedras Campus, University of Puerto Rico, San Juan, PR, USA
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The Involvement of Mg 2+ in Regulation of Cellular and Mitochondrial Functions. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:6797460. [PMID: 28757913 PMCID: PMC5516748 DOI: 10.1155/2017/6797460] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 05/31/2017] [Indexed: 12/11/2022]
Abstract
Mg2+ is an essential mineral with pleotropic impacts on cellular physiology and functions. It acts as a cofactor of several important enzymes, as a regulator of ion channels such as voltage-dependent Ca2+ channels and K+ channels and on Ca2+-binding proteins. In general, Mg2+ is considered as the main intracellular antagonist of Ca2+, which is an essential secondary messenger initiating or regulating a great number of cellular functions. This review examines the effects of Mg2+ on mitochondrial functions with a particular focus on energy metabolism, mitochondrial Ca2+ handling, and apoptosis.
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Yang M, Camara AKS, Aldakkak M, Kwok WM, Stowe DF. Identity and function of a cardiac mitochondrial small conductance Ca 2+-activated K + channel splice variant. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2017; 1858:442-458. [PMID: 28342809 PMCID: PMC5749404 DOI: 10.1016/j.bbabio.2017.03.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 02/28/2017] [Accepted: 03/21/2017] [Indexed: 01/07/2023]
Abstract
We provide evidence for location and function of a small conductance, Ca2+-activated K+ (SKCa) channel isoform 3 (SK3) in mitochondria (m) of guinea pig, rat and human ventricular myocytes. SKCa agonists protected isolated hearts and mitochondria against ischemia/reperfusion (IR) injury; SKCa antagonists worsened IR injury. Intravenous infusion of a SKCa channel agonist/antagonist, respectively, in intact rats was effective in reducing/enhancing regional infarct size induced by coronary artery occlusion. Localization of SK3 in mitochondria was evidenced by Western blot of inner mitochondrial membrane, immunocytochemical staining of cardiomyocytes, and immunogold labeling of isolated mitochondria. We identified a SK3 splice variant in guinea pig (SK3.1, aka SK3a) and human ventricular cells (SK3.2) by amplifying mRNA, and show mitochondrial expression in mouse atrial tumor cells (HL-1) by transfection with full length and truncated SK3.1 protein. We found that the N-terminus is not required for mitochondrial trafficking but the C-terminus beyond the Ca2+ calmodulin binding domain is required for Ca2+ sensing to induce mK+ influx and/or promote mitochondrial localization. In isolated guinea pig mitochondria and in SK3 overexpressed HL-1 cells, mK+ influx was driven by adding CaCl2. Moreover, there was a greater fall in membrane potential (ΔΨm), and enhanced cell death with simulated cell injury after silencing SK3.1 with siRNA. Although SKCa channel opening protects the heart and mitochondria against IR injury, the mechanism for favorable bioenergetics effects resulting from SKCa channel opening remains unclear. SKCa channels could play an essential role in restraining cardiac mitochondria from inducing oxidative stress-induced injury resulting from mCa2+ overload.
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Affiliation(s)
- MeiYing Yang
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Amadou K S Camara
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA; Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Mohammed Aldakkak
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Wai-Meng Kwok
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, USA; Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, USA
| | - David F Stowe
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Biomedical Engineering, Medical College of Wisconsin and Marquette University, Milwaukee, WI, USA; Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, USA; Research Service, Zablocki VA Medical Center, Milwaukee, WI, USA.
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25
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Lee SK, Shanmughapriya S, Mok MC, Dong Z, Tomar D, Carvalho E, Rajan S, Junop MS, Madesh M, Stathopulos PB. Structural Insights into Mitochondrial Calcium Uniporter Regulation by Divalent Cations. Cell Chem Biol 2016; 23:1157-1169. [PMID: 27569754 PMCID: PMC5035232 DOI: 10.1016/j.chembiol.2016.07.012] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 07/04/2016] [Accepted: 07/13/2016] [Indexed: 12/22/2022]
Abstract
Calcium (Ca(2+)) flux into the matrix is tightly controlled by the mitochondrial Ca(2+) uniporter (MCU) due to vital roles in cell death and bioenergetics. However, the precise atomic mechanisms of MCU regulation remain unclear. Here, we solved the crystal structure of the N-terminal matrix domain of human MCU, revealing a β-grasp-like fold with a cluster of negatively charged residues that interacts with divalent cations. Binding of Ca(2+) or Mg(2+) destabilizes and shifts the self-association equilibrium of the domain toward monomer. Mutational disruption of the acidic face weakens oligomerization of the isolated matrix domain and full-length human protein similar to cation binding and markedly decreases MCU activity. Moreover, mitochondrial Mg(2+) loading or blockade of mitochondrial Ca(2+) extrusion suppresses MCU Ca(2+)-uptake rates. Collectively, our data reveal that the β-grasp-like matrix region harbors an MCU-regulating acidic patch that inhibits human MCU activity in response to Mg(2+) and Ca(2+) binding.
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Affiliation(s)
- Samuel K. Lee
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1
| | - Santhanam Shanmughapriya
- Department of Molecular Genetics and Molecular Biochemistry, Center for Translational Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA, 19140
| | - Mac C.Y. Mok
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada, L8S 4K1
| | - Zhiwei Dong
- Department of Molecular Genetics and Molecular Biochemistry, Center for Translational Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA, 19140
| | - Dhanendra Tomar
- Department of Molecular Genetics and Molecular Biochemistry, Center for Translational Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA, 19140
| | - Edmund Carvalho
- Department of Molecular Genetics and Molecular Biochemistry, Center for Translational Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA, 19140
| | - Sudarsan Rajan
- Department of Molecular Genetics and Molecular Biochemistry, Center for Translational Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA, 19140
| | - Murray S. Junop
- Department of Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1
| | - Muniswamy Madesh
- Department of Molecular Genetics and Molecular Biochemistry, Center for Translational Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA, 19140
| | - Peter B. Stathopulos
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1
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