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Szlachta B, Birková A, Čižmárová B, Głogowska-Gruszka A, Zalejska-Fiolka P, Dydoń M, Zalejska-Fiolka J. Erythrocyte Oxidative Status in People with Obesity: Relation to Tissue Losses, Glucose Levels, and Weight Reduction. Antioxidants (Basel) 2024; 13:960. [PMID: 39199206 PMCID: PMC11351941 DOI: 10.3390/antiox13080960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2024] [Revised: 08/02/2024] [Accepted: 08/05/2024] [Indexed: 09/01/2024] Open
Abstract
BACKGROUND This study aimed to investigate the impact of reductions in various body mass components on the erythrocyte oxidative status and glycemic state of people with obesity (PWO). METHODS A total of 53 PWO followed a six-month individualized low-calorie diet with exercise, during which anthropometric, biochemical, and oxidative parameters were measured. The participants were divided into groups based on weight (W), visceral fat area (VFA), total body water (TBW), and skeletal muscle mass (SMM) losses, as well as normoglycemia (NG) and hyperglycemia (HG). RESULTS Weight reduction normalized glycemia and influenced erythrocyte enzyme activity. Regardless of the tissue type lost (VFA, TBW, or SMM), glutathione peroxidase activity decreased in all groups, accompanied by an increase in glutathione reductase activity. Lipofuscin (LPS) and malondialdehyde (MDA) concentrations decreased regardless of the type of tissue lost. The α-/γ-tocopherol ratio increased in those losing >10% body weight, >15% VFA, and >5% TBW. In the NG group, compared to the HG group, there was a decrease in glutathione peroxidase and an increase in glutathione reductase, with these changes being stronger in the HG group. The LPS and MDA concentrations decreased in both groups. Significant correlations were observed between glucose reduction and changes in catalase, retinol, and α-tocopherol, as well as between VFA reduction and changes in vitamin E, L-LPS, and the activities of L-GR and L-GST. CONCLUSIONS This analysis highlights the complex interactions between glucose metabolism, oxidative state, and erythrocyte membrane integrity, crucial for understanding diabetes and its management. This study shows the significant metabolic adaptability of erythrocytes in response to systemic changes induced by obesity and hyperglycemia, suggesting potential therapeutic targets to improve metabolic health in obese individuals.
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Affiliation(s)
- Beata Szlachta
- Department of Biochemistry, Faculty of Medical Science, Zabrze Medical University of Silesia, 40-055 Katowice, Poland; (B.S.); (A.G.-G.); (P.Z.-F.); (M.D.); (J.Z.-F.)
| | - Anna Birková
- Department of Medical and Clinical Biochemistry, Pavol Jozef Šafárik University, 040 11 Košice, Slovakia;
| | - Beáta Čižmárová
- Department of Medical and Clinical Biochemistry, Pavol Jozef Šafárik University, 040 11 Košice, Slovakia;
| | - Anna Głogowska-Gruszka
- Department of Biochemistry, Faculty of Medical Science, Zabrze Medical University of Silesia, 40-055 Katowice, Poland; (B.S.); (A.G.-G.); (P.Z.-F.); (M.D.); (J.Z.-F.)
| | - Paulina Zalejska-Fiolka
- Department of Biochemistry, Faculty of Medical Science, Zabrze Medical University of Silesia, 40-055 Katowice, Poland; (B.S.); (A.G.-G.); (P.Z.-F.); (M.D.); (J.Z.-F.)
| | - Maria Dydoń
- Department of Biochemistry, Faculty of Medical Science, Zabrze Medical University of Silesia, 40-055 Katowice, Poland; (B.S.); (A.G.-G.); (P.Z.-F.); (M.D.); (J.Z.-F.)
| | - Jolanta Zalejska-Fiolka
- Department of Biochemistry, Faculty of Medical Science, Zabrze Medical University of Silesia, 40-055 Katowice, Poland; (B.S.); (A.G.-G.); (P.Z.-F.); (M.D.); (J.Z.-F.)
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Michaels AM, Zoccarato A, Hoare Z, Firth G, Chung YJ, Kuchel PW, Shah AM, Shattock MJ, Southworth R, Eykyn TR. Disrupting Na + ion homeostasis and Na +/K + ATPase activity in breast cancer cells directly modulates glycolysis in vitro and in vivo. Cancer Metab 2024; 12:15. [PMID: 38783368 PMCID: PMC11119389 DOI: 10.1186/s40170-024-00343-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 05/16/2024] [Indexed: 05/25/2024] Open
Abstract
BACKGROUND Glycolytic flux is regulated by the energy demands of the cell. Upregulated glycolysis in cancer cells may therefore result from increased demand for adenosine triphosphate (ATP), however it is unknown what this extra ATP turnover is used for. We hypothesise that an important contribution to the increased glycolytic flux in cancer cells results from the ATP demand of Na+/K+-ATPase (NKA) due to altered sodium ion homeostasis in cancer cells. METHODS Live whole-cell measurements of intracellular sodium [Na+]i were performed in three human breast cancer cells (MDA-MB-231, HCC1954, MCF-7), in murine breast cancer cells (4T1), and control human epithelial cells MCF-10A using triple quantum filtered 23Na nuclear magnetic resonance (NMR) spectroscopy. Glycolytic flux was measured by 2H NMR to monitor conversion of [6,6-2H2]D-glucose to [2H]-labelled L-lactate at baseline and in response to NKA inhibition with ouabain. Intracellular [Na+]i was titrated using isotonic buffers with varying [Na+] and [K+] and introducing an artificial Na+ plasma membrane leak using the ionophore gramicidin-A. Experiments were carried out in parallel with cell viability assays, 1H NMR metabolomics of intracellular and extracellular metabolites, extracellular flux analyses and in vivo measurements in a MDA-MB-231 human-xenograft mouse model using 2-deoxy-2-[18F]fluoroglucose (18F-FDG) positron emission tomography (PET). RESULTS Intracellular [Na+]i was elevated in human and murine breast cancer cells compared to control MCF-10A cells. Acute inhibition of NKA by ouabain resulted in elevated [Na+]i and inhibition of glycolytic flux in all three human cancer cells which are ouabain sensitive, but not in the murine cells which are ouabain resistant. Permeabilization of cell membranes with gramicidin-A led to a titratable increase of [Na+]i in MDA-MB-231 and 4T1 cells and a Na+-dependent increase in glycolytic flux. This was attenuated with ouabain in the human cells but not in the murine cells. 18FDG PET imaging in an MDA-MB-231 human-xenograft mouse model recorded lower 18FDG tumour uptake when treated with ouabain while murine tissue uptake was unaffected. CONCLUSIONS Glycolytic flux correlates with Na+-driven NKA activity in breast cancer cells, providing evidence for the 'centrality of the [Na+]i-NKA nexus' in the mechanistic basis of the Warburg effect.
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Affiliation(s)
- Aidan M Michaels
- School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, London, SE1 7EH, UK
| | - Anna Zoccarato
- School of Cardiovascular and Metabolic Medicine and Sciences, King's College London, London, UK
| | - Zoe Hoare
- School of Cardiovascular and Metabolic Medicine and Sciences, King's College London, London, UK
| | - George Firth
- School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, London, SE1 7EH, UK
| | - Yu Jin Chung
- School of Cardiovascular and Metabolic Medicine and Sciences, King's College London, London, UK
| | - Philip W Kuchel
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, 2006, Australia
| | - Ajay M Shah
- School of Cardiovascular and Metabolic Medicine and Sciences, King's College London, London, UK
| | - Michael J Shattock
- School of Cardiovascular and Metabolic Medicine and Sciences, King's College London, London, UK
| | - Richard Southworth
- School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, London, SE1 7EH, UK
| | - Thomas R Eykyn
- School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, London, SE1 7EH, UK.
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Chatzinikolaou PN, Margaritelis NV, Paschalis V, Theodorou AA, Vrabas IS, Kyparos A, D'Alessandro A, Nikolaidis MG. Erythrocyte metabolism. Acta Physiol (Oxf) 2024; 240:e14081. [PMID: 38270467 DOI: 10.1111/apha.14081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 12/11/2023] [Accepted: 01/01/2024] [Indexed: 01/26/2024]
Abstract
Our aim is to present an updated overview of the erythrocyte metabolism highlighting its richness and complexity. We have manually collected and connected the available biochemical pathways and integrated them into a functional metabolic map. The focus of this map is on the main biochemical pathways consisting of glycolysis, the pentose phosphate pathway, redox metabolism, oxygen metabolism, purine/nucleoside metabolism, and membrane transport. Other recently emerging pathways are also curated, like the methionine salvage pathway, the glyoxalase system, carnitine metabolism, and the lands cycle, as well as remnants of the carboxylic acid metabolism. An additional goal of this review is to present the dynamics of erythrocyte metabolism, providing key numbers used to perform basic quantitative analyses. By synthesizing experimental and computational data, we conclude that glycolysis, pentose phosphate pathway, and redox metabolism are the foundations of erythrocyte metabolism. Additionally, the erythrocyte can sense oxygen levels and oxidative stress adjusting its mechanics, metabolism, and function. In conclusion, fine-tuning of erythrocyte metabolism controls one of the most important biological processes, that is, oxygen loading, transport, and delivery.
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Affiliation(s)
- Panagiotis N Chatzinikolaou
- Department of Physical Education and Sports Science at Serres, Aristotle University of Thessaloniki, Serres, Greece
| | - Nikos V Margaritelis
- Department of Physical Education and Sports Science at Serres, Aristotle University of Thessaloniki, Serres, Greece
| | - Vassilis Paschalis
- School of Physical Education and Sport Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Anastasios A Theodorou
- Department of Life Sciences, School of Sciences, European University Cyprus, Nicosia, Cyprus
| | - Ioannis S Vrabas
- Department of Physical Education and Sports Science at Serres, Aristotle University of Thessaloniki, Serres, Greece
| | - Antonios Kyparos
- Department of Physical Education and Sports Science at Serres, Aristotle University of Thessaloniki, Serres, Greece
| | - Angelo D'Alessandro
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Michalis G Nikolaidis
- Department of Physical Education and Sports Science at Serres, Aristotle University of Thessaloniki, Serres, Greece
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Guizouarn H, Allegrini B. Erythroid glucose transport in health and disease. Pflugers Arch 2020; 472:1371-1383. [PMID: 32474749 DOI: 10.1007/s00424-020-02406-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 05/15/2020] [Accepted: 05/22/2020] [Indexed: 12/14/2022]
Abstract
Glucose transport is intimately linked to red blood cell physiology. Glucose is the unique energy source for these cells, and defects in glucose metabolism or transport activity are associated with impaired red blood cell morphology and deformability leading to reduced lifespan. In vertebrate erythrocytes, glucose transport is mediated by GLUT1 (in humans) or GLUT4 transporters. These proteins also account for dehydroascorbic acid (DHA) transport through erythrocyte membrane. The peculiarities of glucose transporters and the red blood cell pathologies involving GLUT1 are summarized in the present review.
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Affiliation(s)
- Hélène Guizouarn
- Université Côte d'Azur, CNRS, Inserm, Institut de Biologie Valrose, 28 av. Valrose, 06100, Nice, France.
| | - Benoit Allegrini
- Université Côte d'Azur, CNRS, Inserm, Institut de Biologie Valrose, 28 av. Valrose, 06100, Nice, France
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Shishmarev D, Wright AJ, Rodrigues TB, Pileio G, Stevanato G, Brindle KM, Kuchel PW. Sub-minute kinetics of human red cell fumarase: 1 H spin-echo NMR spectroscopy and 13 C rapid-dissolution dynamic nuclear polarization. NMR IN BIOMEDICINE 2018; 31. [PMID: 29315908 DOI: 10.1002/nbm.3870] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 10/13/2017] [Accepted: 10/30/2017] [Indexed: 06/07/2023]
Abstract
Fumarate is an important probe of metabolism in hyperpolarized magnetic resonance imaging and spectroscopy. It is used to detect the release of fumarase in cancer tissues, which is associated with necrosis and drug treatment. Nevertheless, there are limited reports describing the detailed kinetic studies of this enzyme in various cells and tissues. Thus, we aimed to evaluate the sub-minute kinetics of human red blood cell fumarase using nuclear magnetic resonance (NMR) spectroscopy, and to provide a quantitative description of the enzyme that is relevant to the use of fumarate as a probe of cell rupture. The fumarase reaction was studied using time courses of 1 H spin-echo and 13 C-NMR spectra. 1 H-NMR experiments showed that the fumarase reaction in hemolysates is sufficiently rapid to make its kinetics amenable to study in a period of approximately 3 min, a timescale characteristic of hyperpolarized 13 C-NMR spectroscopy. The rapid-dissolution dynamic nuclear polarization (RD-DNP) technique was used to hyperpolarize [1,4-13 C]fumarate, which was injected into concentrated hemolysates. The kinetic data were analyzed using recently developed FmRα analysis and modeling of the enzymatic reaction using Michaelis-Menten equations. In RD-DNP experiments, the decline in the 13 C-NMR signal from fumarate, and the concurrent rise and fall of that from malate, were captured with high spectral resolution and signal-to-noise ratio, which allowed the robust quantification of fumarase kinetics. The kinetic parameters obtained indicate the potential contribution of hemolysis to the overall rate of the fumarase reaction when 13 C-NMR RD-DNP is used to detect necrosis in animal models of implanted tumors. The analytical procedures developed will be applicable to studies of other rapid enzymatic reactions using conventional and hyperpolarized substrate NMR spectroscopy.
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Affiliation(s)
- Dmitry Shishmarev
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Alan J Wright
- Cancer Research UK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Cambridge, UK
| | - Tiago B Rodrigues
- Cancer Research UK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Cambridge, UK
| | - Giuseppe Pileio
- School of Chemistry, University of Southampton, Southampton, UK
| | | | - Kevin M Brindle
- Cancer Research UK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Cambridge, UK
| | - Philip W Kuchel
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
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Application of Heteronuclear NMR Spectroscopy to Bioinorganic and Medicinal Chemistry ☆. REFERENCE MODULE IN CHEMISTRY, MOLECULAR SCIENCES AND CHEMICAL ENGINEERING 2018. [PMCID: PMC7157447 DOI: 10.1016/b978-0-12-409547-2.10947-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Kuchel PW, Shishmarev D. Accelerating metabolism and transmembrane cation flux by distorting red blood cells. SCIENCE ADVANCES 2017; 3:eaao1016. [PMID: 29057326 PMCID: PMC5647125 DOI: 10.1126/sciadv.aao1016] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 09/21/2017] [Indexed: 06/07/2023]
Abstract
Under static conditions, mammalian red blood cells (RBCs) require a continuous supply of energy, typically via glucose, to maintain their biconcave disc shape. Mechanical distortion, in a complementary way, should lead to increased energy demand that is manifest in accelerated glycolysis. The experimental challenge in observing this phenomenon was met by reversibly and reproducibly distorting the cells and noninvasively measuring glycolytic flux. This was done with a gel-distorting device that was coupled with 13C nuclear magnetic resonance (NMR) spectroscopy. We measured [3-13C]l-lactate production from [1,6-13C]d-glucose in the RBCs suspended in gelatin gels, and up to 90% rate enhancements were recorded. Thus, for the first time, we present experiments that demonstrate the linkage of mechanical distortion to metabolic changes in whole mammalian cells. In seeking a mechanism for the linkage between shape and energy supply, we measured transmembrane cation flux with Cs+ (as a K+ congener) using 133Cs NMR spectroscopy, and the cation flux was increased up to fivefold. The postulated mechanism for these notable (in terms of whole-body energy consumption) responses is stimulation of Ca-adenosine triphosphatase by increased transmembrane flux of Ca2+ via the channel protein Piezo1 and increased glycolysis because its flux is adenosine triphosphate demand-regulated.
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Kuchel PW, Shishmarev D, Puckeridge M, Levitt MH, Naumann C, Chapman BE. NMR of (133)Cs(+) in stretched hydrogels: One-dimensional, z- and NOESY spectra, and probing the ion's environment in erythrocytes. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2015; 261:110-120. [PMID: 26561738 DOI: 10.1016/j.jmr.2015.10.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 10/18/2015] [Accepted: 10/21/2015] [Indexed: 06/05/2023]
Abstract
(133)Cs nuclear magnetic resonance (NMR) spectroscopy was conducted on (133)Cs(+) in gelatin hydrogels that were either relaxed or stretched. Stretching generated a septet from this spin-7/2 nucleus, and its nuclear magnetic relaxation was studied via z-spectra, and two-dimensional nuclear Overhauser (NOESY) spectroscopy. Various spectral features were well simulated by using Mathematica and the software package SpinDynamica. Spectra of CsCl in suspensions of human erythrocytes embedded in gelatin gel showed separation of the resonances from the cation inside and outside the cells. Upon stretching the sample, the extracellular (133)Cs(+) signal split into a septet, while the intracellular peak was unchanged, revealing different alignment/ordering properties of the environment inside and around the cells. Differential interference contrast light microscopy confirmed that the cells were stretched when the overall sample was elongated. Analysis of the various spectral features of (133)Cs(+) reported here opens up applications of this K(+) congener for studies of cation-handling by metabolically-active cells and tissues in aligned states.
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Affiliation(s)
- Philip W Kuchel
- School of Molecular Bioscience, University of Sydney, NSW 2006, Australia.
| | - Dmitry Shishmarev
- School of Molecular Bioscience, University of Sydney, NSW 2006, Australia
| | - Max Puckeridge
- School of Molecular Bioscience, University of Sydney, NSW 2006, Australia
| | - Malcolm H Levitt
- Department of Chemistry, University of Southampton, Highfield, SO17 1BJ, UK
| | - Christoph Naumann
- School of Molecular Bioscience, University of Sydney, NSW 2006, Australia
| | - Bogdan E Chapman
- School of Molecular Bioscience, University of Sydney, NSW 2006, Australia
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Salis A, Ninham BW. Models and mechanisms of Hofmeister effects in electrolyte solutions, and colloid and protein systems revisited. Chem Soc Rev 2014; 43:7358-77. [PMID: 25099516 DOI: 10.1039/c4cs00144c] [Citation(s) in RCA: 382] [Impact Index Per Article: 38.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Specific effects of electrolytes have posed a challenge since the 1880's. The pioneering work was that of Franz Hofmeister who studied specific salt induced protein precipitation. These effects are the rule rather the exception and are ubiquitous in chemistry and biology. Conventional electrostatic theories (Debye-Hückel, DLVO, etc.) cannot explain such effects. Over the past decades it has been recognised that additional quantum mechanical dispersion forces with associated hydration effects acting on ions are missing from theory. In parallel Collins has proposed a phenomenological set of rules (the law of matching water affinities, LMWA) which explain and bring to order the order of ion-ion and ion-surface site interactions at a qualitative level. The two approaches appear to conflict. Although the need for inclusion of quantum dispersion forces in one form or another is not questioned, the modelling has often been misleading and inappropriate. It does not properly describe the chemical nature (kosmotropic/chaotropic or hard/soft) of the interacting species. The success of the LMWA rules lies in the fact that they do. Here we point to the way that the two apparently opposing approaches might be reconciled. Notwithstanding, there are more challenges, which deal with the effect of dissolved gas and its connection to 'hydrophobic' interactions, the problem of water at different temperatures and 'water structure' in the presence of solutes. They take us to another dimension that requires the rebuilding of theoretical foundations.
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Affiliation(s)
- Andrea Salis
- Department of Chemical and Geological Science, University of Cagliari, Italy and CSGI.
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Greenstein RJ, Su L, Shahidi A, Brown WD, Clifford A, Brown ST. Unanticipated Mycobacterium tuberculosis complex culture inhibition by immune modulators, immune suppressants, a growth enhancer, and vitamins A and D: clinical implications. Int J Infect Dis 2014; 26:37-43. [PMID: 24998461 DOI: 10.1016/j.ijid.2014.01.026] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 12/26/2013] [Accepted: 01/28/2014] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND The development of novel antibiotics to treat multidrug-resistant (MDR) tuberculosis is time-consuming and expensive. Multiple immune modulators, immune suppressants, anti-inflammatories, and growth enhancers, and vitamins A and D, inhibit Mycobacterium avium subspecies paratuberculosis (MAP) in culture. We studied the culture inhibition of Mycobacterium tuberculosis complex by these agents. METHODS Biosafety level two M. tuberculosis complex (ATCC 19015 and ATCC 25177) was studied in radiometric Bactec or MGIT culture. Agents evaluated included clofazimine, methotrexate, 6-mercaptopurine, cyclosporine A, rapamycin, tacrolimus, monensin, and vitamins A and D. RESULTS All the agents mentioned above caused dose-dependent inhibition of the M. tuberculosis complex. There was no inhibition by the anti-inflammatory 5-aminosalicylic acid, which causes bacteriostatic inhibition of MAP. CONCLUSIONS We conclude that, at a minimum, studies with virulent M. tuberculosis are indicated with the agents mentioned above, as well as with the thioamide 5-propothiouricil, which has previously been shown to inhibit the M. tuberculosis complex in culture. Our data additionally emphasize the importance of vitamins A and D in treating mycobacterial diseases.
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Affiliation(s)
- Robert J Greenstein
- Department of Surgery, James J. Peters Veterans Affairs Medical Center, Bronx, New York, USA; Laboratory of Molecular Surgical Research, James J. Peters Veterans Affairs Medical Center, Bronx, New York, USA.
| | - Liya Su
- Laboratory of Molecular Surgical Research, James J. Peters Veterans Affairs Medical Center, Bronx, New York, USA
| | - Azra Shahidi
- Department of Pathology, James J. Peters Veterans Affairs Medical Center, Bronx, New York, USA
| | - William D Brown
- Laboratory of Molecular Surgical Research, James J. Peters Veterans Affairs Medical Center, Bronx, New York, USA
| | - Anya Clifford
- Laboratory of Molecular Surgical Research, James J. Peters Veterans Affairs Medical Center, Bronx, New York, USA
| | - Sheldon T Brown
- Infectious Disease Section, James J. Peters Veterans Affairs Medical Center, Bronx, New York, USA; Department of Medicine, Icahn School of Medicine at Mt. Sinai, New York, USA
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Puckeridge M, Kuchel PW. Membrane flickering of the human erythrocyte: constrained random walk used with Bayesian analysis. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2014; 43:157-67. [PMID: 24682391 DOI: 10.1007/s00249-014-0951-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Revised: 02/15/2014] [Accepted: 03/03/2014] [Indexed: 10/25/2022]
Abstract
The involvement of adenosine triphosphate (ATP) in erythrocyte (red blood cell; RBC) membrane flickering is of particular interest, because ATP turnover in the cell as a whole is not yet fully accounted for. We sought the origins of flickering by deriving a mathematical model of it, on the basis of the idea of thermally driven collisions of small molecules with the membrane, which responds like an over-damped spring. The model gave simulated responses that were similar to a constrained random walk and had the same frequency-spectral characteristics of membrane displacement as those recorded from RBCs by use of differential interference contrast light microscopy. Bayesian analysis was used as the basis for determination, from experimental results, of the values of the parameters in the model. The analysis was used in the accompanying article in which we investigated the response of membrane flickering to different effector molecules and physicochemical conditions. The results implied ATP was involved only indirectly in membrane flickering.
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Affiliation(s)
- Max Puckeridge
- School of Molecular Bioscience, G08, University of Sydney, Sydney, NSW, 2006, Australia,
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Puckeridge M, Chapman BE, Conigrave AD, Kuchel PW. Membrane flickering of the human erythrocyte: physical and chemical effectors. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2014; 43:169-77. [PMID: 24668224 DOI: 10.1007/s00249-014-0952-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Revised: 02/15/2014] [Accepted: 03/03/2014] [Indexed: 11/30/2022]
Abstract
Recent studies suggest a link between adenosine triphosphate (ATP) concentration and the amplitude of cell membrane flickering (CMF) in the human erythrocyte (red blood cell; RBC). Potentially, the origin of this phenomenon and the unique discocyte shape could be active processes that account for some of the ATP turnover in the RBC. Active flickering could depend on several factors, including pH, osmolality, enzymatic rates and metabolic fluxes. In the present work, we applied the data analysis described in the previous article to study time courses of flickering RBCs acquired using differential interference contrast light microscopy in the presence of selected effectors. We also recorded images of air bubbles in aqueous detergent solutions and oil droplets in water, both of which showed rapid fluctuations in image intensity, the former showing the same type of spectral envelope (relative frequency composition) to RBCs. We conclude that CMF is not directly an active process, but that ATP affects the elastic properties of the membrane that flickers in response to molecular bombardment in a manner that is described mathematically by a constrained random walk.
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Affiliation(s)
- Max Puckeridge
- School of Molecular Bioscience, G08, University of Sydney, Sydney, NSW, 2006, Australia,
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Pagès G, Puckeridge M, Liangfeng G, Tan Y, Jacob C, Garland M, Kuchel P. Transmembrane exchange of hyperpolarized 13C-urea in human erythrocytes: subminute timescale kinetic analysis. Biophys J 2013; 105:1956-66. [PMID: 24209840 PMCID: PMC3824547 DOI: 10.1016/j.bpj.2013.09.034] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 08/28/2013] [Accepted: 09/24/2013] [Indexed: 11/15/2022] Open
Abstract
The rate of exchange of urea across the membranes of human erythrocytes (red blood cells) was quantified on the 1-s to 2-min timescale. (13)C-urea was hyperpolarized and subjected to rapid dissolution and the previously reported (partial) resolution of (13)C NMR resonances from the molecules inside and outside red blood cells in suspensions was observed. This enabled a stopped-flow type of experiment to measure the (initially) zero-trans transport of urea with sequential single-pulse (13)C NMR spectra, every second for up to ~2 min. Data were analyzed using Bayesian reasoning and a Markov chain Monte Carlo method with a set of simultaneous nonlinear differential equations that described nuclear magnetic relaxation combined with transmembrane exchange. Our results contribute to quantitative understanding of urea-exchange kinetics in the whole body; and the methodological approach is likely to be applicable to other cellular systems and tissues in vivo.
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Affiliation(s)
| | - Max Puckeridge
- School of Molecular Bioscience, University of Sydney, Sydney, New South Wales, Australia
| | - Guo Liangfeng
- Institute of Chemical and Engineering Sciences, ASTAR, Singapore
| | - Yee Ling Tan
- Singapore Bioimaging Consortium, ASTAR, Singapore
| | - Chacko Jacob
- Institute of Chemical and Engineering Sciences, ASTAR, Singapore
| | - Marc Garland
- Institute of Chemical and Engineering Sciences, ASTAR, Singapore
| | - Philip W. Kuchel
- Singapore Bioimaging Consortium, ASTAR, Singapore
- School of Molecular Bioscience, University of Sydney, Sydney, New South Wales, Australia
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‘Chiral compartmentation’ in metabolism: Enzyme stereo-specificity yielding evolutionary options. FEBS Lett 2013; 587:2790-7. [DOI: 10.1016/j.febslet.2013.05.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 05/04/2013] [Accepted: 05/06/2013] [Indexed: 10/26/2022]
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