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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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Yan JF, Qin WP, Xiao BC, Wan QQ, Tay FR, Niu LN, Jiao K. Pathological calcification in osteoarthritis: an outcome or a disease initiator? Biol Rev Camb Philos Soc 2020; 95:960-985. [PMID: 32207559 DOI: 10.1111/brv.12595] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 02/27/2020] [Accepted: 03/02/2020] [Indexed: 12/12/2022]
Abstract
In the progression of osteoarthritis, pathological calcification in the affected joint is an important feature. The role of these crystallites in the pathogenesis and progression of osteoarthritis is controversial; it remains unclear whether they act as a disease initiator or are present as a result of joint damage. Recent studies reported that the molecular mechanisms regulating physiological calcification of skeletal tissues are similar to those regulating pathological or ectopic calcification of soft tissues. Pathological calcification takes place when the equilibrium is disrupted. Calcium phosphate crystallites are identified in most affected joints and the presence of these crystallites is closely correlated with the extent of joint destruction. These observations suggest that pathological calcification is most likely to be a disease initiator instead of an outcome of osteoarthritis progression. Inhibiting pathological crystallite deposition within joint tissues therefore represents a potential therapeutic target in the management of osteoarthritis.
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Affiliation(s)
- Jian-Fei Yan
- Department of Oral Mucosal Diseases, State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, School of Stomatology, The Fourth Military Medical University, 145 changle xi road, Xi'an, Shaanxi, 710032, China
| | - Wen-Pin Qin
- Department of Oral Mucosal Diseases, State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, School of Stomatology, The Fourth Military Medical University, 145 changle xi road, Xi'an, Shaanxi, 710032, China
| | - Bo-Cheng Xiao
- Department of Oral Mucosal Diseases, State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, School of Stomatology, The Fourth Military Medical University, 145 changle xi road, Xi'an, Shaanxi, 710032, China
| | - Qian-Qian Wan
- Department of Oral Mucosal Diseases, State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, School of Stomatology, The Fourth Military Medical University, 145 changle xi road, Xi'an, Shaanxi, 710032, China
| | - Franklin R Tay
- Department of Oral Mucosal Diseases, State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, School of Stomatology, The Fourth Military Medical University, 145 changle xi road, Xi'an, Shaanxi, 710032, China.,Department of Endodontics, College of Graduate Studies, Augusta University, 1430, John Wesley Gilbert Drive, Augusta, GA, 30912, U.S.A
| | - Li-Na Niu
- Department of Oral Mucosal Diseases, State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, School of Stomatology, The Fourth Military Medical University, 145 changle xi road, Xi'an, Shaanxi, 710032, China
| | - Kai Jiao
- Department of Oral Mucosal Diseases, State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, School of Stomatology, The Fourth Military Medical University, 145 changle xi road, Xi'an, Shaanxi, 710032, China
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3
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Magnesium Is a Key Player in Neuronal Maturation and Neuropathology. Int J Mol Sci 2019; 20:ijms20143439. [PMID: 31336935 PMCID: PMC6678825 DOI: 10.3390/ijms20143439] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 07/06/2019] [Accepted: 07/09/2019] [Indexed: 01/05/2023] Open
Abstract
Magnesium (Mg) is the second most abundant cation in mammalian cells, and it is essential for numerous cellular processes including enzymatic reactions, ion channel functions, metabolic cycles, cellular signaling, and DNA/RNA stabilities. Because of the versatile and universal nature of Mg2+, the homeostasis of intracellular Mg2+ is physiologically linked to growth, proliferation, differentiation, energy metabolism, and death of cells. On the cellular and tissue levels, maintaining Mg2+ within optimal levels according to the biological context, such as cell types, developmental stages, extracellular environments, and pathophysiological conditions, is crucial for development, normal functions, and diseases. Hence, Mg2+ is pathologically involved in cancers, diabetes, and neurodegenerative diseases, such as Parkinson's disease, Alzheimer's disease, and demyelination. In the research field regarding the roles and mechanisms of Mg2+ regulation, numerous controversies caused by its versatility and complexity still exist. As Mg2+, at least, plays critical roles in neuronal development, healthy normal functions, and diseases, appropriate Mg2+ supplementation exhibits neurotrophic effects in a majority of cases. Hence, the control of Mg2+ homeostasis can be a candidate for therapeutic targets in neuronal diseases. In this review, recent results regarding the roles of intracellular Mg2+ and its regulatory system in determining the cell phenotype, fate, and diseases in the nervous system are summarized, and an overview of the comprehensive roles of Mg2+ is provided.
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Li Y, Wang J, Yue J, Wang Y, Yang C, Cui Q. High magnesium prevents matrix vesicle-mediated mineralization in human bone marrow-derived mesenchymal stem cells via mitochondrial pathway and autophagy. Cell Biol Int 2017; 42:205-215. [PMID: 29024399 DOI: 10.1002/cbin.10888] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2017] [Accepted: 10/07/2017] [Indexed: 01/02/2023]
Abstract
Magnesium, as a physiological calcium antagonist, plays a vital role in the bone metabolism and the balance between magnesium and calcium is crucial in bone physiology. We recently demonstrated that matrix mineralization in human bone marrow-derived mesenchymal stem cells (hBMSCs) can be suppressed by high Mg2+ . However, a complete understanding of the mechanisms involved still remains to be elucidated. As mitochondrial calcium phosphate granules depletion manifests concurrently with the appearance of matrix vesicles (MVs) and autophagy are associated with matrix mineralization, we studied the effect of high extracellular Mg2+ on these pathways. Our results first demonstrated that high Mg2+ has a significant inhibitory effect on the generalization of extracellular mineral aggregates and the expression of collagen 1 along which the mineral crystals grow. Transmission electron microscope results showed that less amount of MVs were observed inside hBMSCs treated with high Mg2+ and high Mg2+ inhibited the release of MVs. In addition, high Mg2+ significantly suppressed mitochondrial Ca2+ accumulation. Autophagy is promoted as a response to osteogenesis of hBMSCs. High Mg2+ inhibited the level of autophagy upon osteogenesis and autophagy inhibitor 3-MA significantly suppressed mineralization. Exogenous ATP can reverse the inhibitory effect of high Mg2+ by increasing the level of autophagy. Taken together, our results indicate that high Mg2+ may modulate MVs-mediated mineralization via suppressing mitochondrial Ca2+ intensity and regulates autophagy of hBMSCs upon osteogenesis, resulting in decreased extracellular mineralized matrix deposition. Our results contribute to the understanding of the role of magnesium homeostasis in osteoporosis and the design of magnesium alloys.
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Affiliation(s)
- Yaqiang Li
- Department of Orthopedics, Shanghai Tenth People's Hospital, Tenth People's Hospital of Tongji University, 301 Middle Yanchang Road, Shanghai, 200072, P.R. China.,Tongji University School of medicine, 1239 Siping Road, Shanghai, 200092, P.R. China
| | - Jing Wang
- Key Laboratory of Advanced Textile Composite Materials of Ministry of Education, Institute of Textile Composite, Tianjin Polytechnic University, Tianjin, 300387, P.R. China
| | - Jiaji Yue
- Department of Orthopedics, Shanghai Tenth People's Hospital, Tenth People's Hospital of Tongji University, 301 Middle Yanchang Road, Shanghai, 200072, P.R. China.,Tongji University School of medicine, 1239 Siping Road, Shanghai, 200092, P.R. China
| | - Yu Wang
- Department of Orthopedics, Shanghai Tenth People's Hospital, Tenth People's Hospital of Tongji University, 301 Middle Yanchang Road, Shanghai, 200072, P.R. China
| | - Chunxi Yang
- Department of Orthopedics, Shanghai Tenth People's Hospital, Tenth People's Hospital of Tongji University, 301 Middle Yanchang Road, Shanghai, 200072, P.R. China
| | - Quanjun Cui
- Department of Orthopaedic Surgery, University of Virginia School of Medicine, Charlottesville, VA, 22903
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5
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Mishra J, Jhun BS, Hurst S, O-Uchi J, Csordás G, Sheu SS. The Mitochondrial Ca 2+ Uniporter: Structure, Function, and Pharmacology. Handb Exp Pharmacol 2017; 240:129-156. [PMID: 28194521 PMCID: PMC5554456 DOI: 10.1007/164_2017_1] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Mitochondrial Ca2+ uptake is crucial for an array of cellular functions while an imbalance can elicit cell death. In this chapter, we briefly reviewed the various modes of mitochondrial Ca2+ uptake and our current understanding of mitochondrial Ca2+ homeostasis in regards to cell physiology and pathophysiology. Further, this chapter focuses on the molecular identities, intracellular regulators as well as the pharmacology of mitochondrial Ca2+ uniporter complex.
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Affiliation(s)
- Jyotsna Mishra
- Center for Translational Medicine, Department of Medicine, Sidney Kimmel Medical College, Thomas Jefferson University, 1020 Locust Street, Suite 543D, Philadelphia, PA, 19107, USA
| | - Bong Sook Jhun
- Cardiovascular Research Center, Department of Medicine, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, 02903, USA
| | - Stephen Hurst
- Center for Translational Medicine, Department of Medicine, Sidney Kimmel Medical College, Thomas Jefferson University, 1020 Locust Street, Suite 543D, Philadelphia, PA, 19107, USA
| | - Jin O-Uchi
- Cardiovascular Research Center, Department of Medicine, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, 02903, USA.
| | - György Csordás
- MitoCare Center for Mitochondrial Imaging Research and Diagnostics, Department of Pathology, Anatomy and Cell Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA.
| | - Shey-Shing Sheu
- Center for Translational Medicine, Department of Medicine, Sidney Kimmel Medical College, Thomas Jefferson University, 1020 Locust Street, Suite 543D, Philadelphia, PA, 19107, USA.
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6
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From Stores to Sinks: Structural Mechanisms of Cytosolic Calcium Regulation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 981:215-251. [PMID: 29594864 DOI: 10.1007/978-3-319-55858-5_10] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
All eukaryotic cells have adapted the use of the calcium ion (Ca2+) as a universal signaling element through the evolution of a toolkit of Ca2+ sensor, buffer and effector proteins. Among these toolkit components, integral and peripheral proteins decorate biomembranes and coordinate the movement of Ca2+ between compartments, sense these concentration changes and elicit physiological signals. These changes in compartmentalized Ca2+ levels are not mutually exclusive as signals propagate between compartments. For example, agonist induced surface receptor stimulation can lead to transient increases in cytosolic Ca2+ sourced from endoplasmic reticulum (ER) stores; the decrease in ER luminal Ca2+ can subsequently signal the opening surface channels which permit the movement of Ca2+ from the extracellular space to the cytosol. Remarkably, the minuscule compartments of mitochondria can function as significant cytosolic Ca2+ sinks by taking up Ca2+ in a coordinated manner. In non-excitable cells, inositol 1,4,5 trisphosphate receptors (IP3Rs) on the ER respond to surface receptor stimulation; stromal interaction molecules (STIMs) sense the ER luminal Ca2+ depletion and activate surface Orai1 channels; surface Orai1 channels selectively permit the movement of Ca2+ from the extracellular space to the cytosol; uptake of Ca2+ into the matrix through the mitochondrial Ca2+ uniporter (MCU) further shapes the cytosolic Ca2+ levels. Recent structural elucidations of these key Ca2+ toolkit components have improved our understanding of how they function to orchestrate precise cytosolic Ca2+ levels for specific physiological responses. This chapter reviews the atomic-resolution structures of IP3R, STIM1, Orai1 and MCU elucidated by X-ray crystallography, electron microscopy and NMR and discusses the mechanisms underlying their biological functions in their respective compartments within the cell.
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7
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Spät A, Szanda G. The Role of Mitochondria in the Activation/Maintenance of SOCE: Store-Operated Ca 2+ Entry and Mitochondria. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 993:257-275. [PMID: 28900919 DOI: 10.1007/978-3-319-57732-6_14] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Mitochondria extensively modify virtually all cellular Ca2+ transport processes, and store-operated Ca2+ entry (SOCE) is no exception to this rule. The interaction between SOCE and mitochondria is complex and reciprocal, substantially altering and, ultimately, fine-tuning both capacitative Ca2+ influx and mitochondrial function. Mitochondria, owing to their considerable Ca2+ accumulation ability, extensively buffer the cytosolic Ca2+ in their vicinity. In turn, the accumulated ion is released back into the neighboring cytosol during net Ca2+ efflux. Since store depletion itself and the successive SOCE are both Ca2+-regulated phenomena, mitochondrial Ca2+ handling may have wide-ranging effects on capacitative Ca2+ influx at any given time. In addition, mitochondria may also produce or consume soluble factors known to affect store-operated channels. On the other hand, Ca2+ entering the cell during SOCE is sensed by mitochondria, and the ensuing mitochondrial Ca2+ uptake boosts mitochondrial energy metabolism and, if Ca2+ overload occurs, may even lead to apoptosis or cell death. In several cell types, mitochondria seem to be sterically excluded from the confined space that forms between the plasma membrane (PM) and endoplasmic reticulum (ER) during SOCE. This implies that high-Ca2+ microdomains comparable to those observed between the ER and mitochondria do not form here. In the following chapter, the above aspects of the many-sided SOCE-mitochondrion interplay will be discussed in greater detail.
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Affiliation(s)
- András Spät
- Department of Physiology, Semmelweis University Medical School, POB 2, 1428, Budapest, Hungary.
- Laboratory of Molecular Physiology, Hungarian Academy of Sciences, Budapest, Hungary.
| | - Gergö Szanda
- Department of Physiology, Semmelweis University Medical School, POB 2, 1428, Budapest, Hungary
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8
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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: 68] [Impact Index Per Article: 8.5] [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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9
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Li Y, Yue J, Yang C. Unraveling the role of Mg(++) in osteoarthritis. Life Sci 2016; 147:24-9. [PMID: 26800786 DOI: 10.1016/j.lfs.2016.01.029] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 01/03/2016] [Accepted: 01/18/2016] [Indexed: 12/29/2022]
Abstract
Mg(++) is widely involved in human physiological processes that may play key roles in the generation and progression of diseases. Osteoarthritis (OA) is a complex joint disorder characterized by articular cartilage degradation, abnormal mineralization and inflammation. Magnesium deficiency is considered to be a major risk factor for OA development and progression. Magnesium deficiency is active in several pathways that have been implicated in OA, including increased inflammatory mediators, cartilage damage, defective chondrocyte biosynthesis, aberrant calcification and a weakened effect of analgesics. Abundant in vitro and in vivo evidence in animal models now suggests that the nutritional supplementation or local infiltration of Mg(++) represent effective therapies for OA. The goal of this review is to summarize the current understanding of the role of Mg(++) in OA with particular emphasis on the related molecular mechanisms involved in OA progression.
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Affiliation(s)
- Yaqiang Li
- Department of Orthopedics, Shanghai Tenth People's Hospital, Tenth People's Hospital of Tongji University, Shanghai, China; School of medicine, Tongji University, Shanghai, China
| | - Jiaji Yue
- Department of Orthopedics, Shanghai Tenth People's Hospital, Tenth People's Hospital of Tongji University, Shanghai, China; School of medicine, Tongji University, Shanghai, China
| | - Chunxi Yang
- Department of Orthopedics, Shanghai Tenth People's Hospital, Tenth People's Hospital of Tongji University, Shanghai, China; School of medicine, Tongji University, Shanghai, China.
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10
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Tewari SG, Camara AKS, Stowe DF, Dash RK. Computational analysis of Ca2+ dynamics in isolated cardiac mitochondria predicts two distinct modes of Ca2+ uptake. J Physiol 2014; 592:1917-30. [PMID: 24591571 DOI: 10.1113/jphysiol.2013.268847] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Cardiac mitochondria can act as a significant Ca(2+) sink and shape cytosolic Ca(2+) signals affecting various cellular processes, such as energy metabolism and excitation-contraction coupling. However, different mitochondrial Ca(2+) uptake mechanisms are still not well understood. In this study, we analysed recently published Ca(2+) uptake experiments performed on isolated guinea pig cardiac mitochondria using a computer model of mitochondrial bioenergetics and cation handling. The model analyses of the data suggest that the majority of mitochondrial Ca(2+) uptake, at physiological levels of cytosolic Ca(2+) and Mg(2+), occurs through a fast Ca(2+) uptake pathway, which is neither the Ca(2+) uniporter nor the rapid mode of Ca(2+) uptake. This fast Ca(2+) uptake component was explained by including a biophysical model of the ryanodine receptor (RyR) in the computer model. However, the Mg(2+)-dependent enhancement of the RyR adaptation was not evident in this RyR-type channel, in contrast to that of cardiac sarcoplasmic reticulum RyR. The extended computer model is corroborated by simulating an independent experimental dataset, featuring mitochondrial Ca(2+) uptake, egress and sequestration. The model analyses of the two datasets validate the existence of two classes of Ca(2+) buffers that comprise the mitochondrial Ca(2+) sequestration system. The modelling study further indicates that the Ca(2+) buffers respond differentially depending on the source of Ca(2+) uptake. In particular, it suggests that the Class 1 Ca(2+) buffering capacity is auto-regulated by the rate at which Ca(2+) is taken up by mitochondria.
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Affiliation(s)
- Shivendra G Tewari
- Biotechnology and Bioengineering Center, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226-6509, USA.
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11
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GAP, an aequorin-based fluorescent indicator for imaging Ca2+ in organelles. Proc Natl Acad Sci U S A 2014; 111:2584-9. [PMID: 24501126 DOI: 10.1073/pnas.1316539111] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Genetically encoded calcium indicators allow monitoring subcellular Ca(2+) signals inside organelles. Most genetically encoded calcium indicators are fusions of endogenous calcium-binding proteins whose functionality in vivo may be perturbed by competition with cellular partners. We describe here a novel family of fluorescent Ca(2+) sensors based on the fusion of two Aequorea victoria proteins, GFP and apo-aequorin (GAP). GAP exhibited a unique combination of features: dual-excitation ratiometric imaging, high dynamic range, good signal-to-noise ratio, insensitivity to pH and Mg(2+), tunable Ca(2+) affinity, uncomplicated calibration, and targetability to five distinct organelles. Moreover, transgenic mice for endoplasmic reticulum-targeted GAP exhibited a robust long-term expression that correlated well with its reproducible performance in various neural tissues. This biosensor fills a gap in the actual repertoire of Ca(2+) indicators for organelles and becomes a valuable tool for in vivo Ca(2+) imaging applications.
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Abstract
The symptoms and signs constituting the congestive heart failure (CHF) syndrome have their pathophysiologic origins rooted in a salt-avid renal state mediated by effector hormones of the renin-angiotensin-aldosterone and adrenergic nervous systems. Controlled clinical trials, conducted over the past decade in patients having minimally to markedly severe symptomatic heart failure, have demonstrated the efficacy of a pharmacologic regimen that interferes with these hormones, including aldosterone receptor binding with either spironolactone or eplerenone. Potential pathophysiologic mechanisms, which have not hitherto been considered involved for the salutary responses and cardioprotection provided by these mineralocorticoid receptor antagonists, are reviewed herein. In particular, we focus on the less well-recognized impact of catecholamines and aldosterone on monovalent and divalent cation dyshomeostasis, which leads to hypokalemia, hypomagnesemia, ionized hypocalcemia with secondary hyperparathyroidism and hypozincemia. Attendant adverse cardiac consequences include a delay in myocardial repolarization with increased propensity for supraventricular and ventricular arrhythmias, and compromised antioxidant defenses with increased susceptibility to nonischemic cardiomyocyte necrosis.
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13
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Abstract
Acute stressor states are inextricably linked to neurohormonal activation which includes the adrenergic nervous system. Consequent elevations in circulating epinephrine and norepinephrine unmask an interdependency that exists between K+, Mg2+ and Ca2+. Catecholamines, for example, regulate the large number of Mg2+-dependent Na/K ATPase pumps present in skeletal muscle. A hyperadrenergic state accounts for a sudden translocation of K+ into muscle and rapid appearance of hypokalemia. In the myocardium, catecholamines promote Mg2+ efflux from cardiomyocytes, whereas intracellular Ca2+ influx and overloading account for the induction of oxidative stress and necrosis of these cells with leakage of their contents, including troponins. Accordingly, acute stressor states can be accompanied by nonischemic elevations in serum troponins, together with the concordant appearance of hypokalemia, hypomagnesemia and ionized hypocalcemia, causing a delay in myocardial repolarization and electrocardiographic QTc prolongation raising the propensity for arrhythmias, including atrial fibrillation and polymorphic ventricular tachycardia. In this review, we focus on the interdependency between K+, Mg2+ and Ca2+ which are clinically relevant to acute stressor states.
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14
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Boelens AD, Pradhan RK, Blomeyer CA, Camara AKS, Dash RK, Stowe DF. Extra-matrix Mg2+ limits Ca2+ uptake and modulates Ca2+ uptake-independent respiration and redox state in cardiac isolated mitochondria. J Bioenerg Biomembr 2013; 45:203-18. [PMID: 23456198 DOI: 10.1007/s10863-013-9500-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 01/24/2013] [Indexed: 12/20/2022]
Abstract
Cardiac mitochondrial matrix (m) free Ca(2+) ([Ca(2+)]m) increases primarily by Ca(2+) uptake through the Ca(2+) uniporter (CU). Ca(2+) uptake via the CU is attenuated by extra-matrix (e) Mg(2+) ([Mg(2+)]e). How [Ca(2+)]m is dynamically modulated by interacting physiological levels of [Ca(2+)]e and [Mg(2+)]e and how this interaction alters bioenergetics are not well understood. We postulated that as [Mg(2+)]e modulates Ca(2+) uptake via the CU, it also alters bioenergetics in a matrix Ca(2+)-induced and matrix Ca(2+)-independent manner. To test this, we measured changes in [Ca(2+)]e, [Ca(2+)]m, [Mg(2+)]e and [Mg(2+)]m spectrofluorometrically in guinea pig cardiac mitochondria in response to added CaCl2 (0-0.6 mM; 1 mM EGTA buffer) with/without added MgCl2 (0-2 mM). In parallel, we assessed effects of added CaCl2 and MgCl2 on NADH, membrane potential (ΔΨm), and respiration. We found that ≥0.125 mM MgCl2 significantly attenuated CU-mediated Ca(2+) uptake and [Ca(2+)]m. Incremental [Mg(2+)]e did not reduce initial Ca(2+)uptake but attenuated the subsequent slower Ca(2+) uptake, so that [Ca(2+)]m remained unaltered over time. Adding CaCl2 without MgCl2 to attain a [Ca(2+)]m from 46 to 221 nM enhanced state 3 NADH oxidation and increased respiration by 15 %; up to 868 nM [Ca(2+)]m did not additionally enhance NADH oxidation or respiration. Adding MgCl2 did not increase [Mg(2+)]m but it altered bioenergetics by its direct effect to decrease Ca(2+) uptake. However, at a given [Ca(2+)]m, state 3 respiration was incrementally attenuated, and state 4 respiration enhanced, by higher [Mg(2+)]e. Thus, [Mg(2+)]e without a change in [Mg(2+)]m can modulate bioenergetics independently of CU-mediated Ca(2+) transport.
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Affiliation(s)
- Age D Boelens
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
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15
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Wei AC, Liu T, Winslow RL, O'Rourke B. Dynamics of matrix-free Ca2+ in cardiac mitochondria: two components of Ca2+ uptake and role of phosphate buffering. ACTA ACUST UNITED AC 2013; 139:465-78. [PMID: 22641641 PMCID: PMC3362519 DOI: 10.1085/jgp.201210784] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Mitochondrial Ca(2+) uptake is thought to provide an important signal to increase energy production to meet demand but, in excess, can also trigger cell death. The mechanisms defining the relationship between total Ca(2+) uptake, changes in mitochondrial matrix free Ca(2+), and the activation of the mitochondrial permeability transition pore (PTP) are not well understood. We quantitatively measure changes in [Ca(2+)](out) and [Ca(2+)](mito) during Ca(2+) uptake in isolated cardiac mitochondria and identify two components of Ca(2+) influx. [Ca(2+)](mito) recordings revealed that the first, MCU(mode1), required at least 1 µM Ru360 to be completely inhibited, and responded to small Ca(2+) additions in the range of 0.1 to 2 µM with rapid and large changes in [Ca(2+)](mito). The second component, MCU(mode2), was blocked by 100 nM Ru360 and was responsible for the bulk of total Ca(2+) uptake for large Ca(2+) additions in the range of 2 to 10 µM; however, it had little effect on steady-state [Ca(2+)](mito). MCU(mode1) mediates changes in [Ca(2+)](mito) of 10s of μM, even in the presence of 100 nM Ru360, indicating that there is a finite degree of Ca(2+) buffering in the matrix associated with this pathway. In contrast, the much higher Ca(2+) loads evoked by MCU(mode2) activate a secondary dynamic Ca(2+) buffering system consistent with calcium-phosphate complex formation. Increasing P(i) potentiated [Ca(2+)](mito) increases via MCU(mode1) but suppressed [Ca(2+)](mito) changes via MCU(mode2). The results suggest that the role of MCU(mode1) might be to modulate oxidative phosphorylation in response to intracellular Ca(2+) signaling, whereas MCU(mode2) and the dynamic high-capacity Ca(2+) buffering system constitute a Ca(2+) sink function. Interestingly, the trigger for PTP activation is unlikely to be [Ca(2+)](mito) itself but rather a downstream byproduct of total mitochondrial Ca(2+) loading.
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Affiliation(s)
- An-Chi Wei
- Division of Cardiology, Department of Medicine, Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205, USA
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16
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Alonso MT, Manjarrés IM, García-Sancho J. Privileged coupling between Ca(2+) entry through plasma membrane store-operated Ca(2+) channels and the endoplasmic reticulum Ca(2+) pump. Mol Cell Endocrinol 2012; 353:37-44. [PMID: 21878366 DOI: 10.1016/j.mce.2011.08.021] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Revised: 08/10/2011] [Accepted: 08/15/2011] [Indexed: 12/17/2022]
Abstract
The sarco/endoplasmic reticulum Ca(2+)-ATPase (SERCA) is the third element of capacitative calcium entry. It colocalizes with STIM1 and Orai1 at puncta, where couples plasma membrane store-operated Ca(2+) channels (SOC) to Ca(2+) pumping into the ER. The efficiency of this calcium entry-calcium refilling (CECR) coupling is comparable to the classic excitation-response transduction mechanisms. This allows efficient filling of the endoplasmic reticulum (ER) with the Ca(2+) entering through SOC channels with little progression of the Ca(2+) wave towards the cell core. CECR coupling is very sensitive to changes in stoichiometry among STIM, Orai and SERCA, with excess Orai antagonizing ER refilling. ER takes up most of the calcium load that enters through SOC, whereas mitochondria take up a very small fraction. This difference is due to the spatial positioning with regard to SOC, the amplitude of the high Ca(2+) microdomains, and the differences in the Ca(2+) affinity of the uptake mechanisms.
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Affiliation(s)
- María Teresa Alonso
- Instituto de Biología y Genética Molecular, Universidad de Valladolid y Consejo Superior de Investigaciones Científicas, c/ Sanz y Forés s/n, 47003 Valladolid, Spain
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17
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Szanda G, Rajki A, Spät A. Control mechanisms of mitochondrial Ca(2+) uptake - feed-forward modulation of aldosterone secretion. Mol Cell Endocrinol 2012; 353:101-8. [PMID: 21924321 DOI: 10.1016/j.mce.2011.08.042] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Revised: 08/31/2011] [Accepted: 08/31/2011] [Indexed: 12/23/2022]
Abstract
Mitochondrial Ca(2+) signal activates metabolism by boosting pyridine nucleotide reduction and ATP synthesis or, if Ca(2+) sequestration is supraphysiological, may even lead to apoptosis. Although the molecular background of mitochondrial Ca(2+) uptake has recently been elucidated, the regulation of Ca(2+) handling is still not properly clarified. In human adrenocortical H295R cells we found a regulatory mechanism involving p38 MAPK and novel-type PKC isoforms. Upon stimulation with angiotensin II (AII) these kinases are activated typically prior to the release of Ca(2+) and - most probably by reducing the Ca(2+) permeation through the outer mitochondrial membrane - attenuate mitochondrial Ca(2+) uptake in a feed-forward manner. The biologic significance of the kinase-mediated reduction of mitochondrial Ca(2+) signal is also reflected by the attenuation of AII-mediated aldosterone secretion. As another feed-forward mechanism, we found in HEK-293T and H295R cells that Ca(2+) signal evoked either by IP(3) or by voltage-gated influx is accompanied by a concomitant cytosolic Mg(2+) signal. In permeabilized HEK-293T cells Mg(2+) was found to be a potent inhibitor of mitochondrial Ca(2+) uptake in the physiologic [Mg(2+)] and [Ca(2+)] range. Thus, these inhibitory mechanisms may serve not only as protection against mitochondrial Ca(2+) overload and subsequent apoptosis but also have the potential to substantially alter physiological responses.
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Affiliation(s)
- Gergö Szanda
- Department of Physiology, Semmelweis University, POB 259, H-1444 Budapest, Hungary
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18
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Csordás G, Várnai P, Golenár T, Sheu SS, Hajnóczky G. Calcium transport across the inner mitochondrial membrane: molecular mechanisms and pharmacology. Mol Cell Endocrinol 2012; 353:109-13. [PMID: 22123069 PMCID: PMC3295916 DOI: 10.1016/j.mce.2011.11.011] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Revised: 11/10/2011] [Accepted: 11/10/2011] [Indexed: 01/21/2023]
Abstract
Growing evidence supports that mitochondrial calcium uptake is important for cell metabolism, signaling and survival. However, both the molecular nature of the mitochondrial Ca(2+) transport sites and the calcium signals they respond to remained elusive. Recent RNA interference studies have identified new candidate proteins for Ca(2+) transport across the inner mitochondrial membrane, including LETM1, MCU, MICU1 and NCLX. The sensitivity of these factors to several drugs has been tested and in parallel, some new inhibitors of mitochondrial Ca(2+) uptake have been described. This paper provides an update on the pharmacological aspects of the molecular mechanisms of the inner mitochondrial membrane Ca(2+) transport.
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Affiliation(s)
- György Csordás
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107
| | - Peter Várnai
- Department of Physiology, Semmelweis University Budapest, Hungary
| | - Tünde Golenár
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107
| | - Shey-Shing Sheu
- Center for Translational Medicine, Thomas Jefferson University, Philadelphia, PA 19107
| | - György Hajnóczky
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107
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19
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Spät A, Szanda G. Special features of mitochondrial Ca²⁺ signalling in adrenal glomerulosa cells. Pflugers Arch 2012; 464:43-50. [PMID: 22395411 DOI: 10.1007/s00424-012-1086-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Revised: 02/10/2012] [Accepted: 02/14/2012] [Indexed: 11/30/2022]
Abstract
Aldosterone, secreted by adrenal glomerulosa cells, allows the adaptation of the vertebrate organism to a wide range of physiological and pathological stimuli including acute haemodynamic challenges and long-term changes in dietary sodium and potassium intake. Most of the extracellular signals are mediated by cytosolic Ca²⁺ signal deriving from Ca²⁺ release, store-operated and/or voltage-gated Ca²⁺ influx. Mitochondria in glomerulosa cells play a fundamental role in generating and modulating the final biological response. These organelles not only house several enzymes of aldosterone biosynthesis but also-in a Ca²⁺-dependent manner-provide NADPH for the function of these enzymes. Moreover, mitochondria, constituting a high portion of cytoplasmic volume and displaying a uniquely low-threshold Ca²⁺ sequestering ability, shape and thus modulate the decoding of the complex cytosolic Ca²⁺ response. The unusual features of mitochondrial Ca²⁺ signalling that permit such an integrative function in adrenal glomerulosa cells are hereby described.
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Affiliation(s)
- András Spät
- Department of Physiology, Semmelweis University, Budapest, Hungary.
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20
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Si D, Epstein T, Lee YEK, Kopelman R. Nanoparticle PEBBLE sensors for quantitative nanomolar imaging of intracellular free calcium ions. Anal Chem 2012; 84:978-86. [PMID: 22122409 DOI: 10.1021/ac202521e] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ca(2+) is a universal second messenger and plays a major role in intracellular signaling, metabolism, and a wide range of cellular processes. To date, one of the most successful approaches for intracellular Ca(2+) measurement involves the introduction of optically sensitive Ca(2+) indicators into living cells, combined with digital imaging microscopy. However, the use of free Ca(2+) indicators for intracellular sensing and imaging has several limitations, such as nonratiometric measurement for the most-sensitive indicators, cytotoxicity of the indicators, interference from nonspecific binding caused by cellular biomacromolecules, challenging calibration, and unwanted sequestration of the indicator molecules. These problems are minimized when the Ca(2+) indicators are encapsulated inside porous and inert polyacrylamide nanoparticles. We present PEBBLE nanosensors encapsulated with rhodamine-based Ca(2+) fluorescence indicators. The rhod-2-containing PEBBLEs presented here show a stable sensing range at near-neutral pH (pH 6-9). Because of the protection of the PEBBLE matrix, the interference of protein-nonspecific binding to the indicator is minimal. The rhod-2 PEBBLEs give a nanomolar dynamic sensing range for both in-solution (K(d) = 478 nM) and intracellular (K(d) = 293 nM) measurements. These nanosensors are useful quantitative tools for the measurement and imaging of the cytosolic nanomolar free Ca(2+) levels.
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Affiliation(s)
- Di Si
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
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21
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Pradhan RK, Qi F, Beard DA, Dash RK. Characterization of Mg2+ inhibition of mitochondrial Ca2+ uptake by a mechanistic model of mitochondrial Ca2+ uniporter. Biophys J 2011; 101:2071-81. [PMID: 22067144 DOI: 10.1016/j.bpj.2011.09.029] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Revised: 09/15/2011] [Accepted: 09/19/2011] [Indexed: 01/13/2023] Open
Abstract
Ca(2+) is an important regulatory ion and alteration of mitochondrial Ca(2+) homeostasis can lead to cellular dysfunction and apoptosis. Ca(2+) is transported into respiring mitochondria via the Ca(2+) uniporter, which is known to be inhibited by Mg(2+). This uniporter-mediated mitochondrial Ca(2+) transport is also shown to be influenced by inorganic phosphate (Pi). Despite a large number of experimental studies, the kinetic mechanisms associated with the Mg(2+) inhibition and Pi regulation of the uniporter function are not well established. To gain a quantitative understanding of the effects of Mg(2+) and Pi on the uniporter function, we developed here a mathematical model based on known kinetic properties of the uniporter and presumed Mg(2+) inhibition and Pi regulation mechanisms. The model is extended from our previous model of the uniporter that is based on a multistate catalytic binding and interconversion mechanism and Eyring's free energy barrier theory for interconversion. The model satisfactorily describes a wide variety of experimental data sets on the kinetics of mitochondrial Ca(2+) uptake. The model also appropriately depicts the inhibitory effect of Mg(2+) on the uniporter function, in which Ca(2+) uptake is hyperbolic in the absence of Mg(2+) and sigmoid in the presence of Mg(2+). The model suggests a mixed-type inhibition mechanism for Mg(2+) inhibition of the uniporter function. This model is critical for building mechanistic models of mitochondrial bioenergetics and Ca(2+) handling to understand the mechanisms by which Ca(2+) mediates signaling pathways and modulates energy metabolism.
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Affiliation(s)
- Ranjan K Pradhan
- Biotechnology and Bioengineering Center and Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
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22
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Szanda G, Halász E, Spät A. Protein kinases reduce mitochondrial Ca2+ uptake through an action on the outer mitochondrial membrane. Cell Calcium 2010; 48:168-75. [DOI: 10.1016/j.ceca.2010.08.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 08/10/2010] [Accepted: 08/12/2010] [Indexed: 12/30/2022]
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23
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Santo-Domingo J, Demaurex N. Calcium uptake mechanisms of mitochondria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:907-12. [PMID: 20079335 DOI: 10.1016/j.bbabio.2010.01.005] [Citation(s) in RCA: 227] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2009] [Revised: 01/06/2010] [Accepted: 01/08/2010] [Indexed: 12/16/2022]
Abstract
The ability of mitochondria to capture Ca2+ ions has important functional implications for cells, because mitochondria shape cellular Ca2+ signals by acting as a Ca2+ buffer and respond to Ca2+ elevations either by increasing the cell energy supply or by triggering the cell death program of apoptosis. A mitochondrial Ca2+ channel known as the uniporter drives the rapid and massive entry of Ca2+ ions into mitochondria. The uniporter operates at high, micromolar cytosolic Ca2+ concentrations that are only reached transiently in cells, near Ca2+ release channels. Mitochondria can also take up Ca2+ at low, nanomolar concentrations, but this high affinity mode of Ca2+ uptake is not well characterized. Recently, leucine-zipper-EF hand-containing transmembrane region (Letm1) was proposed to be an electrogenic 1:1 mitochondrial Ca2+/H+ antiporter that drives the uptake of Ca2+ into mitochondria at nanomolar cytosolic Ca2+ concentrations. In this article, we will review the properties of the Ca2+ import systems of mitochondria and discuss how Ca2+ uptake via an electrogenic 1:1 Ca2+/H+ antiport challenges our current thinking of the mitochondrial Ca2+ uptake mechanism.
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Affiliation(s)
- Jaime Santo-Domingo
- Department of Cell Physiology and Metabolism, University of Geneva, 1, rue Michel-Servet, CH-1211 Geneva 4, Switzerland
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24
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Koncz P, Szanda G, Fülöp L, Rajki A, Spät A. Mitochondrial Ca2+ uptake is inhibited by a concerted action of p38 MAPK and protein kinase D. Cell Calcium 2009; 46:122-9. [DOI: 10.1016/j.ceca.2009.06.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2009] [Revised: 06/05/2009] [Accepted: 06/20/2009] [Indexed: 10/20/2022]
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