1
|
Istfan N, Hasson B, Apovian C, Meshulam T, Yu L, Anderson W, Corkey BE. Acute carbohydrate overfeeding: a redox model of insulin action and its impact on metabolic dysfunction in humans. Am J Physiol Endocrinol Metab 2021; 321:E636-E651. [PMID: 34569273 PMCID: PMC8782668 DOI: 10.1152/ajpendo.00094.2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 08/23/2021] [Accepted: 09/20/2021] [Indexed: 11/22/2022]
Abstract
A role for fat overfeeding in metabolic dysfunction in humans is commonly implied in the literature. Comparatively less is known about acute carbohydrate overfeeding (COF). We tested the hypothesis that COF predisposes to oxidative stress by channeling electrons away from antioxidants to support energy storage. In a study of 24 healthy human subjects with and without obesity, COF was simulated by oral administration of excess carbohydrates; a two-step hyperinsulinemic clamp was used to evaluate insulin action. The distribution of electrons between oxidative and reductive pathways was evaluated by the changes in the reduction potentials (Eh) of cytoplasmic (lactate, pyruvate) and mitochondrial (β-hydroxybutyrate, acetoacetate) redox couples. Antioxidant redox was measured by the ratio of reduced to oxidized glutathione. We used cross-correlation analysis to evaluate the relationships between the trajectories of Eh, insulin, glucose, and respiratory exchange during COF. DDIT3 and XBP1s/u mRNA were measured as markers of endoplasmic reticulum stress (ER stress) in adipose tissue before and after COF. Here, we show that acute COF is characterized by net transfer of electrons from mitochondria to cytoplasm. Circulating glutathione is oxidized in a manner that significantly cross-correlates with increasing insulin levels and precedes the decrease in cytoplasmic Eh. This effect is more pronounced in overweight individuals (OW). Markers of ER stress in subcutaneous fat are detectable in OW within 4 h. We conclude that acute COF contributes to metabolic dysfunction through insulin-dependent pathways that promote electron transfer to the cytoplasm and decrease antioxidant capacity. Characterization of redox during overfeeding is important for understanding the pathophysiology of obesity and type 2 diabetes.NEW & NOTEWORTHY Current principles assume that conversion of thermic energy to metabolically useful energy follows fixed rules. These principles ignore the possibility of variable proton uncoupling in mitochondria. Our study shows that the net balance of electron distribution between mitochondria and cytoplasm is influenced by insulin in a manner that reduces proton leakage during overfeeding. Characterization of the effects of insulin on redox balance is important for understanding obesity and insulin resistance.
Collapse
Affiliation(s)
- Nawfal Istfan
- Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital, Boston, Massachusetts
| | | | - Caroline Apovian
- Division of Endocrinology, Diabetes, and Hypertension, Brigham and Women's Hospital, Boston, Massachusetts
| | - Tova Meshulam
- Section of Endocrinology, Diabetes, and Nutrition, Boston Medical Center and Boston University School of Medicine, Boston, Massachusetts
| | - Liqun Yu
- Section of Endocrinology, Diabetes, and Nutrition, Boston Medical Center and Boston University School of Medicine, Boston, Massachusetts
| | - Wendy Anderson
- Section of Endocrinology, Diabetes, and Nutrition, Boston Medical Center and Boston University School of Medicine, Boston, Massachusetts
- Section of Minimally Invasive Surgery, Boston Medical Center, Boston, Massachusetts
| | - Barbara E Corkey
- Section of Endocrinology, Diabetes, and Nutrition, Boston Medical Center and Boston University School of Medicine, Boston, Massachusetts
| |
Collapse
|
2
|
Adhikari A, Mondal S, Das M, Ghosh R, Biswas P, Darbar S, Singh S, Das AK, Bhattacharya SS, Pal D, Mallick AK, Pal SK. Redox Buffering Capacity of Nanomaterials as an Index of ROS-Based Therapeutics and Toxicity: A Preclinical Animal Study. ACS Biomater Sci Eng 2021; 7:2475-2484. [PMID: 34060316 DOI: 10.1021/acsbiomaterials.1c00402] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Precise control of intracellular redox status, i.e., maintenance of the physiological level of reactive oxygen species (ROS) for mediating normal cellular functions (oxidative eustress) while evading the excess ROS stress (distress), is central to the concept of redox medicine. In this regard, engineered nanoparticles with unique ROS generation, transition, and depletion functions have the potential to be the choice of redox therapeutics. However, it is always challenging to estimate whether ROS-induced intracellular events are beneficial or deleterious to the cell. Here, we propose the concept of redox buffering capacity as a therapeutic index of engineered nanomaterials. As a steady redox state is maintained for normal functioning cells, we hypothesize that the ability of a nanomaterial to preserve this homeostatic condition will dictate its therapeutic efficacy. Additionally, the redox buffering capacity is expected to provide information about the nanoparticle toxicity. Here, using citrate-functionalized trimanganese tetroxide nanoparticles (C-Mn3O4 NPs) as a model nanosystem, we explored its redox buffering capacity in erythrocytes. Furthermore, we went on to study the chronic toxic effect (if any) of this nanomaterial in the animal model to co-relate with the experimentally estimated redox buffering capacity. This study could function as a framework for assessing the capability of a nanomaterial as redox medicine (whether maintains eustress or damages by creating distress), thus orienting its application and safety for clinical use.
Collapse
Affiliation(s)
- Aniruddha Adhikari
- Department of Chemical, Biological and Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector 3, Salt Lake, Kolkata 700106, India
| | - Susmita Mondal
- Department of Chemical, Biological and Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector 3, Salt Lake, Kolkata 700106, India
| | - Monojit Das
- Department of Zoology, Uluberia College, University of Calcutta, Uluberia, Howrah 711315, India.,Department of Zoology, Vidyasagar University, Vidyasagar University Road, Rangamati, Midnapore 721102, India
| | - Ria Ghosh
- Technical Research Centre, S. N. Bose National Centre for Basic Sciences, Block JD, Sector 3, Salt Lake, Kolkata 700106, India
| | - Pritam Biswas
- Department of Microbiology, St. Xavier's College, 30, Mother Teresa Sarani, Kolkata 700016, India
| | - Soumendra Darbar
- Research and Development Division, Dey's Medical Stores (Mfg.) Pvt. Ltd., 62 Bondel Road, Ballygunge, Kolkata 700019, India
| | - Soumendra Singh
- Technical Research Centre, S. N. Bose National Centre for Basic Sciences, Block JD, Sector 3, Salt Lake, Kolkata 700106, India
| | - Anjan Kumar Das
- Department of Pathology, Coochbehar Govt. Medical College and Hospital, Silver Jubilee Road, Coochbehar 736101, India
| | | | - Debasish Pal
- Department of Zoology, Uluberia College, University of Calcutta, Uluberia, Howrah 711315, India
| | - Asim Kumar Mallick
- Department of Pediatric Medicine, Nil Ratan Sirkar Medical College and Hospital, 138 AJC Bose Road, Sealdah, Rajabazar, Kolkata 700014, India
| | - Samir Kumar Pal
- Department of Chemical, Biological and Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector 3, Salt Lake, Kolkata 700106, India.,Department of Zoology, Uluberia College, University of Calcutta, Uluberia, Howrah 711315, India.,Technical Research Centre, S. N. Bose National Centre for Basic Sciences, Block JD, Sector 3, Salt Lake, Kolkata 700106, India
| |
Collapse
|
3
|
Prosser KE, Xie D, Chu A, MacNeil GA, Varju BR, Kadakia RT, Que EL, Walsby CJ. Copper(II) Pyridyl Aminophenolates: Hypoxia-Selective, Nucleus-Targeting Cytotoxins, and Magnetic Resonance Probes. Chemistry 2021; 27:9839-9849. [PMID: 33878230 DOI: 10.1002/chem.202100603] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Indexed: 11/10/2022]
Abstract
Targeting the low-oxygen (hypoxic) environments found in many tumours by using redox-active metal complexes is a strategy that can enhance efficacy and reduce the side effects of chemotherapies. We have developed a series of CuII complexes with tridentate pyridine aminophenolate-based ligands for preferential activation in the reduction window provided by hypoxic tissues. Furthermore, ligand functionalization with a pendant CF3 group provides a 19 F spectroscopic handle for magnetic-resonance studies of redox processes at the metal centre and behaviour in cellular environments. The phenol group in the ligand backbone was substituted at the para position with H, Cl, and NO2 to modulate the reduction potential of the CuII centre, giving a range of values below the window expected for hypoxic tissues. The NO2 -substituted complex, which has the highest reduction potential, showed enhanced cytotoxic selectivity towards HeLa cells grown under hypoxic conditions. Cell death occurs by apoptosis, as determined by analysis of the cell morphology. A combination of 19 F NMR and ICP-OES indicates localization of the NO2 complex in HeLa cell nuclei and increased cellular accumulation under hypoxia. This correlates with DNA nuclease activity being the likely origin of cytotoxic activity, as demonstrated by cleavage of DNA plasmids in the presence of the CuII nitro complex and a reducing agent. Selective detection of the paramagnetic CuII complexes and their diamagnetic ligands by 19 F MRI suggests hypoxia-targeting theranostic applications by redox activation.
Collapse
Affiliation(s)
- Kathleen E Prosser
- Department of Chemistry, Simon Fraser University, 8888 University Dr., Burnaby, BC V5A 1S6, Canada.,Department of Chemistry, The University of Texas at Austin, 105 E. 24th Street Stop A5300, Austin, TX 78712, USA
| | - Da Xie
- Department of Chemistry, The University of Texas at Austin, 105 E. 24th Street Stop A5300, Austin, TX 78712, USA
| | - Annica Chu
- Department of Chemistry, Simon Fraser University, 8888 University Dr., Burnaby, BC V5A 1S6, Canada
| | - Gregory A MacNeil
- Department of Chemistry, Simon Fraser University, 8888 University Dr., Burnaby, BC V5A 1S6, Canada
| | - Bryton R Varju
- Department of Chemistry, Simon Fraser University, 8888 University Dr., Burnaby, BC V5A 1S6, Canada
| | - Rahul T Kadakia
- Department of Chemistry, The University of Texas at Austin, 105 E. 24th Street Stop A5300, Austin, TX 78712, USA
| | - Emily L Que
- Department of Chemistry, The University of Texas at Austin, 105 E. 24th Street Stop A5300, Austin, TX 78712, USA
| | - Charles J Walsby
- Department of Chemistry, Simon Fraser University, 8888 University Dr., Burnaby, BC V5A 1S6, Canada
| |
Collapse
|
4
|
Rubino FM. The Redox Potential of the β- 93-Cysteine Thiol Group in Human Hemoglobin Estimated from In Vitro Oxidant Challenge Experiments. Molecules 2021; 26:molecules26092528. [PMID: 33926119 PMCID: PMC8123695 DOI: 10.3390/molecules26092528] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 04/22/2021] [Accepted: 04/23/2021] [Indexed: 11/16/2022] Open
Abstract
Glutathionyl hemoglobin is a minor form of hemoglobin with intriguing properties. The measurement of the redox potential of its reactive β-93-Cysteine is useful to improve understanding of the response of erythrocytes to transient and chronic conditions of oxidative stress, where the level of glutathionyl hemoglobin is increased. An independent literature experiment describes the recovery of human erythrocytes exposed to an oxidant burst by measuring glutathione, glutathione disulfide and glutathionyl hemoglobin in a two-hour period. This article calculates a value for the redox potential E0 of the β-93-Cysteine, considering the erythrocyte as a closed system at equilibrium described by the Nernst equation and using the measurements of the literature experiment. The obtained value of E0 of −121 mV at pH 7.4 places hemoglobin as the most oxidizing thiol of the erythrocyte. By using as synthetic indicators of the concentrations the electrochemical potentials of the two main redox pairs in the erythrocytes, those of glutathione–glutathione disulfide and of glutathionyl–hemoglobin, the mechanism of the recovery phase can be hypothesized. Hemoglobin acts as the redox buffer that scavenges oxidized glutathione in the oxidative phase and releases it in the recovery phase, by acting as the substrate of the NAD(P)H-cofactored enzymes.
Collapse
Affiliation(s)
- Federico Maria Rubino
- LaTMA Laboratory for Analytical Toxicology and Metabonomics, Department of Health Sciences, Università degli Studi di Milano at "Ospedale San Paolo" v. A. di Rudinì 8, I-20142 Milano, Italy
| |
Collapse
|
5
|
Clement S, Campbell JM, Deng W, Guller A, Nisar S, Liu G, Wilson BC, Goldys EM. Mechanisms for Tuning Engineered Nanomaterials to Enhance Radiation Therapy of Cancer. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:2003584. [PMID: 33344143 PMCID: PMC7740107 DOI: 10.1002/advs.202003584] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Indexed: 05/12/2023]
Abstract
Engineered nanomaterials that produce reactive oxygen species on exposure to X- and gamma-rays used in radiation therapy offer promise of novel cancer treatment strategies. Similar to photodynamic therapy but suitable for large and deep tumors, this new approach where nanomaterials acting as sensitizing agents are combined with clinical radiation can be effective at well-tolerated low radiation doses. Suitably engineered nanomaterials can enhance cancer radiotherapy by increasing the tumor selectivity and decreasing side effects. Additionally, the nanomaterial platform offers therapeutically valuable functionalities, including molecular targeting, drug/gene delivery, and adaptive responses to trigger drug release. The potential of such nanomaterials to be combined with radiotherapy is widely recognized. In order for further breakthroughs to be made, and to facilitate clinical translation, the applicable principles and fundamentals should be articulated. This review focuses on mechanisms underpinning rational nanomaterial design to enhance radiation therapy, the understanding of which will enable novel ways to optimize its therapeutic efficacy. A roadmap for designing nanomaterials with optimized anticancer performance is also shown and the potential clinical significance and future translation are discussed.
Collapse
Affiliation(s)
- Sandhya Clement
- ARC Centre of Excellence for Nanoscale BiophotonicsThe Graduate School of Biomedical EngineeringUniversity of New South WalesHigh StreetKensingtonNew South Wales2052Australia
| | - Jared M. Campbell
- ARC Centre of Excellence for Nanoscale BiophotonicsThe Graduate School of Biomedical EngineeringUniversity of New South WalesHigh StreetKensingtonNew South Wales2052Australia
| | - Wei Deng
- ARC Centre of Excellence for Nanoscale BiophotonicsThe Graduate School of Biomedical EngineeringUniversity of New South WalesHigh StreetKensingtonNew South Wales2052Australia
| | - Anna Guller
- ARC Centre of Excellence for Nanoscale BiophotonicsThe Graduate School of Biomedical EngineeringUniversity of New South WalesHigh StreetKensingtonNew South Wales2052Australia
- Institute for Regenerative MedicineSechenov First Moscow State Medical University (Sechenov University)Trubetskaya StreetMoscow119991Russia
| | - Saadia Nisar
- ARC Centre of Excellence for Nanoscale BiophotonicsThe Graduate School of Biomedical EngineeringUniversity of New South WalesHigh StreetKensingtonNew South Wales2052Australia
| | - Guozhen Liu
- ARC Centre of Excellence for Nanoscale BiophotonicsThe Graduate School of Biomedical EngineeringUniversity of New South WalesHigh StreetKensingtonNew South Wales2052Australia
| | - Brian C. Wilson
- Department of Medical BiophysicsUniversity of Toronto/Princess Margaret Cancer CentreUniversity Health NetworkColledge StreetTorontoOntarioON M5G 2C1Canada
| | - Ewa M. Goldys
- ARC Centre of Excellence for Nanoscale BiophotonicsThe Graduate School of Biomedical EngineeringUniversity of New South WalesHigh StreetKensingtonNew South Wales2052Australia
| |
Collapse
|
6
|
Stein KT, Moon SJ, Nguyen AN, Sikes HD. Kinetic modeling of H2O2 dynamics in the mitochondria of HeLa cells. PLoS Comput Biol 2020; 16:e1008202. [PMID: 32925922 PMCID: PMC7515204 DOI: 10.1371/journal.pcbi.1008202] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 09/24/2020] [Accepted: 07/28/2020] [Indexed: 12/15/2022] Open
Abstract
Hydrogen peroxide (H2O2) promotes a range of phenotypes depending on its intracellular concentration and dosing kinetics, including cell death. While this qualitative relationship has been well established, the quantitative and mechanistic aspects of H2O2 signaling are still being elucidated. Mitochondria, a putative source of intracellular H2O2, have recently been demonstrated to be particularly vulnerable to localized H2O2 perturbations, eliciting a dramatic cell death response in comparison to similar cytosolic perturbations. We sought to improve our dynamic and mechanistic understanding of the mitochondrial H2O2 reaction network in HeLa cells by creating a kinetic model of this system and using it to explore basal and perturbed conditions. The model uses the most current quantitative proteomic and kinetic data available to predict reaction rates and steady-state concentrations of H2O2 and its reaction partners within individual mitochondria. Time scales ranging from milliseconds to one hour were simulated. We predict that basal, steady-state mitochondrial H2O2 will be in the low nM range (2–4 nM) and will be inversely dependent on the total pool of peroxiredoxin-3 (Prx3). Neglecting efflux of H2O2 to the cytosol, the mitochondrial reaction network is expected to control perturbations well up to H2O2 generation rates ~50 μM/s (0.25 nmol/mg-protein/s), above which point the Prx3 system would be expected to collapse. Comparison of these results with redox Western blots of Prx3 and Prx2 oxidation states demonstrated reasonable trend agreement at short times (≤ 15 min) for a range of experimentally perturbed H2O2 generation rates. At longer times, substantial efflux of H2O2 from the mitochondria to the cytosol was evidenced by peroxiredoxin-2 (Prx2) oxidation, and Prx3 collapse was not observed. A refined model using Monte Carlo parameter sampling was used to explore rates of H2O2 efflux that could reconcile model predictions of Prx3 oxidation states with the experimental observations. Cancer is a complex disease that caused the deaths of over 9 million people worldwide in 2018, according to the WHO. While great strides have been made in treating many cancers, effective chemotherapies still carry difficult side effects, motivating the search for more targeted and selective treatments that act minimally in healthy cells. The Selective Cancer Killing Hypothesis is based on the idea that some cancers exist at endogenous levels of reactive oxygen species that are higher than healthy cells, so if a patient were systemically treated with a redox-based chemotherapeutic that raises all cells’ levels of reactive oxygen species, only the cancer cells would cross a toxicity threshold. This hypothesis is attractive because it would minimize side effects in healthy cells, but the quantitative knowledge of endogenous oxidant concentrations that would be helpful in refining and testing this hypothesis is not widely established. Our model predicts the range of relevant hydrogen peroxide concentrations in the mitochondria of the HeLa model cancer cell line and suggests experimental measurements of tumor cells and tissues that may be useful in quantifying steady state concentrations of this oxidant.
Collapse
Affiliation(s)
- Kassi T. Stein
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States of America
| | - Sun Jin Moon
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States of America
| | - Athena N. Nguyen
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States of America
| | - Hadley D. Sikes
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States of America
- * E-mail:
| |
Collapse
|
7
|
1H-NMR-based metabolomics to investigate the effects of Phoenix dactylifera seed extracts in LPS-IFN-γ-induced RAW 264.7 cells. Food Res Int 2019; 125:108565. [PMID: 31554083 DOI: 10.1016/j.foodres.2019.108565] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 06/24/2019] [Accepted: 07/14/2019] [Indexed: 12/13/2022]
Abstract
Inflammation has been revealed to play a central role in the onset and progression of many illnesses. Nuclear magnetic resonance (NMR) based metabolomics method was adopted to evaluate the effects of Phoenix dactylifera seeds, in particular the Algerian date variety of Deglet on the metabolome of the LPS-IFN-γ-induced RAW 264.7 cells. Variations in the extracellular and intracellular profiles emphasized the differences in the presence of tyrosine, phenylalanine, alanine, proline, asparagine, isocitrate, inosine and lysine. Principal component analysis (PCA) revealed noticeable clustering patterns between the treated and induced RAW cells based on the metabolic profile of the extracellular metabolites. However, the effects of treatment on the intracellular metabolites appears to be less distinct as suggested by the PCA and heatmap analyses. A clear group segregation was observed for the intracellular metabolites from the treated and induced cells based on the orthogonal partial least squares-discriminant analysis (OPLS-DA) score plot. Likewise, 11 of the metabolites in the treated cells were significantly different from those in the induced groups, including amino acids and succinate. The enrichment analysis demonstrated that treatment with Deglet seed extracts interfered with the energy and of amino acids metabolism. Overall, the obtained data reinforced the possible application of Deglet seeds as a functional food with anti-inflammatory properties.
Collapse
|
8
|
Langford TF, Deen WM, Sikes HD. A mathematical analysis of Prx2-STAT3 disulfide exchange rate constants for a bimolecular reaction mechanism. Free Radic Biol Med 2018; 120:239-245. [PMID: 29574146 DOI: 10.1016/j.freeradbiomed.2018.03.039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 03/09/2018] [Accepted: 03/20/2018] [Indexed: 10/17/2022]
Abstract
Appreciation of peroxiredoxins as the major regulators of H2O2 concentrations in human cells has led to a new understanding of redox signaling. In addition to their status as the primary reducers of H2O2 to water, the oxidized peroxiredoxin byproduct of this reaction has recently been shown capable of participation in H2O2-mediated signaling pathways through disulfide exchange reactions with the transcription factor STAT3. The dynamics of peroxidase-transcription factor disulfide exchange reactions have not yet been considered in detail with respect to how these reactions fit into the larger network of competing reactions in human cells. In this study, we used a kinetic model of oxidation and reduction reactions related to H2O2 metabolism in the cytosol of human cells to study the dynamics of peroxiredoxin-2 mediated oxidation of the redox-regulated transcription factor STAT3. In combination with previously reported experimental data, the model was used to estimate the rate coefficient of a biomolecular reaction between Prx2 and STAT3 for two sets of assumptions that constitute lower and upper bound cases. Using these estimates, we calculated the relative rates of the reaction of oxidized peroxiredoxin-2 and STAT3 and other competing reactions in the cytosol. These calculations revealed that peroxiredoxin-2-mediated oxidation of STAT3 likely occurs at a much slower rate than competing reactions in the cytosol. This analysis suggests the existence of more complex mechanisms, potentially involving currently unknown protein-protein recognition partners, which facilitate disulfide exchange reactions between peroxiredoxin-2 and STAT3.
Collapse
Affiliation(s)
- Troy F Langford
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge 02139, USA
| | - William M Deen
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge 02139, USA
| | - Hadley D Sikes
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge 02139, USA.
| |
Collapse
|
9
|
Martinovich GG, Martinovich IV, Vcherashniaya AV, Zenkov NK, Menshchikova EB, Kandalintseva NV, Cherenkevich SN. Mechanisms of Redox Regulation of Chemoresistance in Tumor Cells by Phenolic Antioxidants. Biophysics (Nagoya-shi) 2018. [DOI: 10.1134/s000635091706015x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
|
10
|
Moreno-Sánchez R, Gallardo-Pérez JC, Rodríguez-Enríquez S, Saavedra E, Marín-Hernández Á. Control of the NADPH supply for oxidative stress handling in cancer cells. Free Radic Biol Med 2017; 112:149-161. [PMID: 28739529 DOI: 10.1016/j.freeradbiomed.2017.07.018] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 07/19/2017] [Accepted: 07/20/2017] [Indexed: 01/10/2023]
Abstract
It has not been systematically analyzed whether the NADPH supply is a limiting factor for oxidative stress management in cancer cells. In the present work, it was determined in non-cancer and cancer cells the protein contents and kinetomics of (i) the cytosolic enzymes responsible for the NADPH production (i.e., Glc6PDH, 6PGDH, ME, IDH-1); and (ii) the two main enzymes responsible for NADPH/NADP+ and GSH/GSSG recycling (GR, GPx-1) associated to oxidative stress management. With these data, kinetic models were built and further validated. Rat liver and hepatoma AS-30D cytosolic fractions exhibited greater Vmax for IDH-1 than for Glc6PDH and 6PGDH whereas human cancer cells and platelets showed greater Vmax for Glc6PDH than for 6PGDH and IDH-1. The ME activity was comparatively low in all cell types tested. The Km values for the respective specific substrates were all similar among the different cell types. Most activities were lower in AS-30D cells than in liver. In contrast, IDH-1, Glc6PDH and GR activities in human cancer cells were similar or greater to those of platelets, but GPx-1 activity was severely suppressed, despite showing similar GPx-1 protein content vs. platelets. Kinetic analysis and pathway modeling revealed a previously unveiled feedback IDH-1 regulation by GSH. The oxidative stress management in cancer cells (i) was mainly controlled by GPx-1 and the main NADPH provider was Glc6PDH; and (ii) modeling indicated that NADPH supply was not a controlling step. These data suggested that Glc6PDH and GPx-1 are adequate and promising targets for anti-cancer therapeutic intervention.
Collapse
Affiliation(s)
- Rafael Moreno-Sánchez
- Instituto Nacional de Cardiología, Departamento de Bioquímica, Ciudad de México, Tlalpan 14080, Mexico
| | | | - Sara Rodríguez-Enríquez
- Instituto Nacional de Cardiología, Departamento de Bioquímica, Ciudad de México, Tlalpan 14080, Mexico
| | - Emma Saavedra
- Instituto Nacional de Cardiología, Departamento de Bioquímica, Ciudad de México, Tlalpan 14080, Mexico
| | - Álvaro Marín-Hernández
- Instituto Nacional de Cardiología, Departamento de Bioquímica, Ciudad de México, Tlalpan 14080, Mexico.
| |
Collapse
|
11
|
Bozhkov AI, Nikitchenko YV, Klimova EM, Linkevych OS, Lebid KM, Al-Bahadli AMM, Alsardia MMA. Young and old rats have different strategies of metabolic adaptation to Cu-induced liver fibrosis. ADVANCES IN GERONTOLOGY 2017. [DOI: 10.1134/s2079057017010040] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
|
12
|
Martinovich GG, Martinovich IV, Vcherashniaya AV, Shadyro OI, Cherenkevich SN. Thymoquinone, a biologically active component of Nigella sativa, induces mitochondrial production of reactive oxygen species and programmed death of tumor cells. Biophysics (Nagoya-shi) 2017. [DOI: 10.1134/s0006350916060154] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
13
|
Lim JB, Huang BK, Deen WM, Sikes HD. Analysis of the lifetime and spatial localization of hydrogen peroxide generated in the cytosol using a reduced kinetic model. Free Radic Biol Med 2015; 89:47-53. [PMID: 26169725 DOI: 10.1016/j.freeradbiomed.2015.07.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 06/30/2015] [Accepted: 07/08/2015] [Indexed: 01/12/2023]
Abstract
Hydrogen peroxide (H2O2) acts as a signaling molecule via its reactions with particular cysteine residues of certain proteins. Determining the roles of direct oxidation by H2O2 versus disulfide exchange reactions (i.e. relay reactions) between oxidized and reduced proteins of different identities is a current focus. Here, we use kinetic modeling to estimate the spatial and temporal localization of H2O2 and its most likely oxidation targets during a sudden increase in H2O2 above the basal level in the cytosol. We updated a previous redox kinetic model with recently measured parameters for HeLa cells and used the model to estimate the length and time scales of H2O2 diffusion through the cytosol before it is consumed by reaction. These estimates were on the order of one micron and one millisecond, respectively. We found oxidation of peroxiredoxin by H2O2 to be the dominant reaction in the network and that the overall concentration of reduced peroxiredoxin is not significantly affected by physiological increases in intracellular H2O2 concentration. We used this information to reduce the model from 22 parameters and reactions and 21 species to a single analytical equation with only one dependent variable, i.e. the concentration of H2O2, and reproduced results from the complete model. The reduced kinetic model will facilitate future efforts to progress beyond estimates and precisely quantify how reactions and diffusion jointly influence the distribution of H2O2 within cells.
Collapse
Affiliation(s)
- Joseph B Lim
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Beijing K Huang
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - William M Deen
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Hadley D Sikes
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| |
Collapse
|
14
|
Wang Y, Lin FX, Zhao Y, Wang MZ, Ge XW, Gong ZX, Bao DD, Gu YF. The sustained-release behavior and in vitro and in vivo transfection of pEGFP-loaded core-shell-structured chitosan-based composite particles. Int J Nanomedicine 2014; 9:4965-78. [PMID: 25364253 PMCID: PMC4211910 DOI: 10.2147/ijn.s58104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Novel submicron core-shell-structured chitosan-based composite particles encapsulated with enhanced green fluorescent protein plasmids (pEGFP) were prepared by complex coacervation method. The core was pEGFP-loaded thiolated N-alkylated chitosan (TACS) and the shell was pH- and temperature-responsive hydroxybutyl chitosan (HBC). pEGFP-loaded TACS-HBC composite particles were spherical, and had a mean diameter of approximately 120 nm, as measured by transmission electron microscopy and particle size analyzer. pEGFP showed sustained release in vitro for >15 days. Furthermore, in vitro transfection in human embryonic kidney 293T and human cervix epithelial cells, and in vivo transfection in mice skeletal muscle of loaded pEGFP, were investigated. Results showed that the expression of loaded pEGFP, both in vitro and in vivo, was slow but could be sustained over a long period. pEGFP expression in mice skeletal muscle was sustained for >60 days. This work indicates that these submicron core-shell-structured chitosan-based composite particles could potentially be used as a gene vector for in vivo controlled gene transfection.
Collapse
Affiliation(s)
- Yun Wang
- Department of Plastic Surgery, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, People's Republic of China
| | - Fu-xing Lin
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui, People's Republic of China
| | - Yu Zhao
- Department of Plastic Surgery, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, People's Republic of China
| | - Mo-zhen Wang
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui, People's Republic of China
| | - Xue-wu Ge
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui, People's Republic of China
| | - Zheng-xing Gong
- Department of Plastic Surgery, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, People's Republic of China
| | - Dan-dan Bao
- Department of Plastic Surgery, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, People's Republic of China
| | - Yu-fang Gu
- Department of Plastic Surgery, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, People's Republic of China
| |
Collapse
|
15
|
Physico-Chemical, Biological and Therapeutic Characteristics of Electrolyzed Reduced Alkaline Water (ERAW). WATER 2013. [DOI: 10.3390/w5042094] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
16
|
Rodrigues FS, Souza MA, Magni DV, Ferreira APO, Mota BC, Cardoso AM, Paim M, Xavier LL, Ferreira J, Schetinger MRC, Da Costa JC, Royes LFF, Fighera MR. N-acetylcysteine prevents spatial memory impairment induced by chronic early postnatal glutaric acid and lipopolysaccharide in rat pups. PLoS One 2013; 8:e78332. [PMID: 24205200 PMCID: PMC3813430 DOI: 10.1371/journal.pone.0078332] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 09/11/2013] [Indexed: 12/18/2022] Open
Abstract
Background and Aims Glutaric aciduria type I (GA-I) is characterized by accumulation of glutaric acid (GA) and neurological symptoms, such as cognitive impairment. Although this disease is related to oxidative stress and inflammation, it is not known whether these processes facilitate the memory impairment. Our objective was to investigate the performance of rat pups chronically injected with GA and lipopolysaccharide (LPS) in spatial memory test, antioxidant defenses, cytokines levels, Na+, K+-ATPase activity, and hippocampal volume. We also evaluated the effect of N-acetylcysteine (NAC) on theses markers. Methods Rat pups were injected with GA (5umol g of body weight-1, subcutaneously; twice per day; from 5th to 28th day of life), and were supplemented with NAC (150mg/kg/day; intragastric gavage; for the same period). LPS (2mg/kg; E.coli 055 B5) or vehicle (saline 0.9%) was injected intraperitoneally, once per day, from 25th to 28th day of life. Oxidative stress and inflammatory biomarkers as well as hippocampal volume were assessed. Results GA caused spatial learning deficit in the Barnes maze and LPS potentiated this effect. GA and LPS increased TNF-α and IL-1β levels. The co-administration of these compounds potentiated the increase of IL-1β levels but not TNF-α levels in the hippocampus. GA and LPS increased TBARS (thiobarbituric acid-reactive substance) content, reduced antioxidant defenses and inhibited Na+, K+-ATPase activity. GA and LPS co-administration did not have additive effect on oxidative stress markers and Na+, K+ pump. The hippocampal volume did not change after GA or LPS administration. NAC protected against impairment of spatial learning and increase of cytokines levels. NAC Also protected against inhibition of Na+,K+-ATPase activity and oxidative markers. Conclusions These results suggest that inflammatory and oxidative markers may underlie at least in part of the neuropathology of GA-I in this model. Thus, NAC could represent a possible adjuvant therapy in treatment of children with GA-I.
Collapse
Affiliation(s)
- Fernanda S Rodrigues
- Centro de Ciências da Saúde, Departamento de Neuropsiquiatria, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brasil ; Centro de Ciências Naturais e Exatas, Programa de Pós-graduação em Ciências Biológicas: Bioquímica Toxicológica, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brasil ; Centro de Educação Física e Desportos, Departamento de Métodos e Técnicas Desportivas, Laboratório de Bioquímica do Exercício (BIOEX), Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brasil
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Pillay CS, Hofmeyr JH, Mashamaite LN, Rohwer JM. From top-down to bottom-up: computational modeling approaches for cellular redoxin networks. Antioxid Redox Signal 2013; 18:2075-86. [PMID: 23249367 DOI: 10.1089/ars.2012.4771] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
SIGNIFICANCE Thioredoxin, glutaredoxin, and peroxiredoxin systems play critical roles in a large number of redox-sensitive cellular processes. These systems are linked to each other by coupled redox cycles and common reaction intermediates into a larger network. Given the scale and connectivity of this network, computational approaches are required to analyze its dynamics and organization. RECENT ADVANCES Theoretical advances, as well as new redox proteomic methods, have led to the development of both top-down and bottom-up systems biology approaches to analyze the these systems and the network as a whole. Top-down approaches have been based on modifications to the Nernst equation or on graph theoretical approaches, while bottom-up approaches have been based on kinetic or stoichiometric modeling techniques. CRITICAL ISSUES This review will consider the rationale behind these approaches and focus on their advantages and limitations. Further, the review will discuss modeling standards to ensure model accuracy and availability. FUTURE DIRECTIONS Top-down and bottom-up approaches have distinct strengths and limitations in describing cellular redoxin networks. The availability of methods to overcome these limitations, together with the adoption of common modeling standards, is expected to increase the pace of model-led discovery within the redox biology field.
Collapse
Affiliation(s)
- Ché S Pillay
- School of Life Sciences, University of Kwa-Zulu Natal, Scottsville, South Africa.
| | | | | | | |
Collapse
|
18
|
Zuris JA, Ali SS, Yeh H, Nguyen TA, Nechushtai R, Paddock ML, Jennings PA. NADPH inhibits [2Fe-2S] cluster protein transfer from diabetes drug target MitoNEET to an apo-acceptor protein. J Biol Chem 2012; 287:11649-55. [PMID: 22351774 DOI: 10.1074/jbc.m111.319731] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
MitoNEET (mNT) is the founding member of the recently discovered CDGSH family of [2Fe-2S] proteins capable of [2Fe-2S] cluster transfer to apo-acceptor proteins. It is a target of the thiazolidinedione (TZD) class of anti-diabetes drugs whose binding modulate both electron transfer and cluster transfer properties. The [2Fe-2S] cluster in mNT is destabilized upon binding of NADPH, which leads to loss of the [2Fe-2S] cluster to the solution environment. Because mNT is capable of transferring [2Fe-2S] clusters to apo-acceptor proteins, we sought to determine whether NADPH binding also affects cluster transfer. We show that NADPH inhibits transfer of the [2Fe-2S] cluster to an apo-acceptor protein with an inhibition constant (K(i)) of 200 μm, which reflects that of NADPH concentrations expected under physiological conditions. In addition, we determined that the strictly conserved cluster interacting residue Asp-84 in the CDGSH domain is necessary for the NADPH-dependent inhibition of [2Fe-2S] cluster transfer. The most critical cellular function of NADPH is in the maintenance of a pool of reducing equivalents, which is essential to counteract oxidative damage. Taken together, our findings suggest that NADPH can regulate both mNT [2Fe-2S] cluster levels in the cell as well as the ability of the protein to transfer [2Fe-2S] clusters to cytosolic or mitochondrial acceptors.
Collapse
Affiliation(s)
- John A Zuris
- Department of Chemistry, University of California at San Diego, La Jolla, California 92093, USA
| | | | | | | | | | | | | |
Collapse
|
19
|
A switching mechanism in doxorubicin bioactivation can be exploited to control doxorubicin toxicity. PLoS Comput Biol 2011; 7:e1002151. [PMID: 21935349 PMCID: PMC3174179 DOI: 10.1371/journal.pcbi.1002151] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Accepted: 06/21/2011] [Indexed: 02/07/2023] Open
Abstract
Although doxorubicin toxicity in cancer cells is multifactorial, the enzymatic bioactivation of the drug can significantly contribute to its cytotoxicity. Previous research has identified most of the components that comprise the doxorubicin bioactivation network; however, adaptation of the network to changes in doxorubicin treatment or to patient-specific changes in network components is much less understood. To investigate the properties of the coupled reduction/oxidation reactions of the doxorubicin bioactivation network, we analyzed metabolic differences between two patient-derived acute lymphoblastic leukemia (ALL) cell lines exhibiting varied doxorubicin sensitivities. We developed computational models that accurately predicted doxorubicin bioactivation in both ALL cell lines at high and low doxorubicin concentrations. Oxygen-dependent redox cycling promoted superoxide accumulation while NADPH-dependent reductive conversion promoted semiquinone doxorubicin. This fundamental switch in control is observed between doxorubicin sensitive and insensitive ALL cells and between high and low doxorubicin concentrations. We demonstrate that pharmacological intervention strategies can be employed to either enhance or impede doxorubicin cytotoxicity in ALL cells due to the switching that occurs between oxygen-dependent superoxide generation and NADPH-dependent doxorubicin semiquinone formation. In the United States, acute lymphoblastic leukemia (ALL) is the most common form of cancer among children. Although the survival rate of childhood leukemia is relatively high, those who do not respond to chemotherapy have very low prognostic outcome. Recent reports point to the critical role of metabolism in determining cell sensitivity to doxorubicin, a conventional drug used in leukemia treatment. Most of the molecular components involved in doxorubicin metabolism have been identified; however, how these components operate as a system and how adaptation of the doxorubicin metabolic network to patient-specific changes in protein components is much less understood. We have therefore chosen to investigate via computational modeling the variations in the distribution of proteins that metabolize doxorubicin can control a cell's ability to respond to doxorubicin treatment. This systems-level approach provides a framework for understanding how patient-specific variability leads to patient-sensitivity to doxorubicin treatment at different doses. With this knowledge, we were able to correctly predict complex behavior induced by pharmacological intervention strategies for manipulation of doxorubicin metabolism. When our interventions are used in combination with doxorubicin, cell viability was promoted or potentiated based on dominant control mechanisms within the metabolic network.
Collapse
|
20
|
Martinovich GG, Martinovich IV, Cherenkevich SN. Redox regulation of cellular processes: A biophysical model and experiment. Biophysics (Nagoya-shi) 2011. [DOI: 10.1134/s0006350911030171] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
|
21
|
Gorman-Lewis D, Aryal BP, Paunesku T, Vogt S, Lai B, Woloschak GE, Jensen MP. Direct determination of the intracellular oxidation state of plutonium. Inorg Chem 2011; 50:7591-7. [PMID: 21755934 PMCID: PMC3688463 DOI: 10.1021/ic200588p] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Microprobe X-ray absorption near edge structure (μ-XANES) measurements were used to determine directly, for the first time, the oxidation state of intracellular plutonium in individual 0.1-μm(2) areas within single rat pheochromocytoma cells (PC12). The living cells were incubated in vitro for 3 h in the presence of Pu added to the media in different oxidation states (Pu(III), Pu(IV), and Pu(VI)) and in different chemical forms. Regardless of the initial oxidation state or chemical form of Pu presented to the cells, the XANES spectra of the intracellular Pu deposits were always consistent with tetravalent Pu even though the intracellular milieu is generally reducing.
Collapse
Affiliation(s)
- Drew Gorman-Lewis
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | | | | | | | | | | | | |
Collapse
|
22
|
Facile transfer of [2Fe-2S] clusters from the diabetes drug target mitoNEET to an apo-acceptor protein. Proc Natl Acad Sci U S A 2011; 108:13047-52. [PMID: 21788481 DOI: 10.1073/pnas.1109986108] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
MitoNEET (mNT) is an outer mitochondrial membrane target of the thiazolidinedione diabetes drugs with a unique fold and a labile [2Fe-2S] cluster. The rare 1-His and 3-Cys coordination of mNT's [2Fe-2S] leads to cluster lability that is strongly dependent on the presence of the single histidine ligand (His87). These properties of mNT are similar to known [2Fe-2S] shuttle proteins. Here we investigated whether mNT is capable of cluster transfer to acceptor protein(s). Facile [2Fe-2S] cluster transfer is observed between oxidized mNT and apo-ferredoxin (a-Fd) using UV-VIS spectroscopy and native-PAGE, as well as with a mitochondrial iron detection assay in cells. The transfer is unidirectional, proceeds to completion, and occurs with a second-order-reaction rate that is comparable to known iron-sulfur transfer proteins. Mutagenesis of His87 with Cys (H87C) inhibits transfer of the [2Fe-2S] clusters to a-Fd. This inhibition is beyond that expected from increased cluster kinetic stability, as the equivalently stable Lys55 to Glu (K55E) mutation did not inhibit transfer. The H87C mutant also failed to transfer its iron to mitochondria in HEK293 cells. The diabetes drug pioglitazone inhibits iron transfer from WT mNT to mitochondria, indicating that pioglitazone affects a specific property, [2Fe-2S] cluster transfer, in the cellular environment. This finding is interesting in light of the role of iron overload in diabetes. Our findings suggest a likely role for mNT in [2Fe-2S] and/or iron transfer to acceptor proteins and support the idea that pioglitazone's antidiabetic mode of action may, in part, be to inhibit transfer of mNT's [2Fe-2S] cluster.
Collapse
|
23
|
Zuris JA, Halim DA, Conlan AR, Abresch EC, Nechushtai R, Paddock ML, Jennings PA. Engineering the redox potential over a wide range within a new class of FeS proteins. J Am Chem Soc 2010; 132:13120-2. [PMID: 20812736 PMCID: PMC2944382 DOI: 10.1021/ja103920k] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2010] [Indexed: 11/30/2022]
Abstract
MitoNEET is a newly discovered mitochondrial protein and a target of the TZD class of antidiabetes drugs. MitoNEET is homodimeric with each protomer binding a [2Fe-2S] center through a rare 3-Cys and 1-His coordination geometry. Both the fold and the coordination of the [2Fe-2S] centers suggest that it could have novel properties compared to other known [2Fe-2S] proteins. We tested the robustness of mitoNEET to mutation and the range over which the redox potential (E(M)) could be tuned. We found that the protein could tolerate an array of mutations that modified the E(M) of the [2Fe-2S] center over a range of ∼700 mV, which is the largest E(M) range engineered in an FeS protein and, importantly, spans the cellular redox range (+200 to -300 mV). These properties make mitoNEET potentially useful for both physiological studies and industrial applications as a stable, water-soluble, redox agent.
Collapse
|
24
|
Adimora NJ, Jones DP, Kemp ML. A model of redox kinetics implicates the thiol proteome in cellular hydrogen peroxide responses. Antioxid Redox Signal 2010; 13:731-43. [PMID: 20121341 PMCID: PMC2935341 DOI: 10.1089/ars.2009.2968] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Hydrogen peroxide is appreciated as a cellular signaling molecule with second-messenger properties, yet the mechanisms by which the cell protects against intracellular H(2)O(2) accumulation are not fully understood. We introduce a network model of H(2)O(2) clearance that includes the pseudo-enzymatic oxidative turnover of protein thiols, the enzymatic actions of catalase, glutathione peroxidase, peroxiredoxin, and glutaredoxin, and the redox reactions of thioredoxin and glutathione. Simulations reproduced experimental observations of the rapid and transient oxidation of glutathione and the rapid, sustained oxidation of thioredoxin on exposure to extracellular H(2)O(2). The model correctly predicted early oxidation profiles for the glutathione and thioredoxin redox couples across a range of initial extracellular [H(2)O(2)] and highlights the importance of cytoplasmic membrane permeability to the cellular defense against exogenous sources of H(2)O(2). The protein oxidation profile predicted by the model suggests that approximately 10% of intracellular protein thiols react with hydrogen peroxide at substantial rates, with a majority of these proteins forming protein disulfides as opposed to protein S-glutathionylated adducts. A steady-state flux analysis predicted an unequal distribution of the intracellular anti-oxidative burden between thioredoxin-dependent and glutathione-dependent antioxidant pathways, with the former contributing the majority of the cellular antioxidant defense due to peroxiredoxins and protein disulfides.
Collapse
Affiliation(s)
- Nnenna J Adimora
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia, USA
| | | | | |
Collapse
|
25
|
Martinovich GG, Martinovich IV, Cherenkevich SN, Sauer H. Redox Buffer Capacity of the Cell: Theoretical and Experimental Approach. Cell Biochem Biophys 2010; 58:75-83. [DOI: 10.1007/s12013-010-9090-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
26
|
Rosales-Corral S, Reiter RJ, Tan DX, Ortiz GG, Lopez-Armas G. Functional aspects of redox control during neuroinflammation. Antioxid Redox Signal 2010; 13:193-247. [PMID: 19951033 DOI: 10.1089/ars.2009.2629] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Neuroinflammation is a CNS reaction to injury in which some severe pathologies, regardless of their origin, converge. The phenomenon emphasizes crosstalk between neurons and glia and reveals a complex interaction with oxidizing agents through redox sensors localized in enzymes, receptors, and transcription factors. When oxidizing pressures cause reversible molecular changes, such as minimal or transitory proinflammatory cytokine overproduction, redox couples provide a means of translating the presence of reactive oxygen or nitrogen species into useful signals in the cell. Additionally, thiol-based redox sensors convey information about localized changes in redox potential induced by physiologic or pathologic situations. They are susceptible to oxidative changes and become key events during neuroinflammation, altering the course of a signaling response or the behavior of specific transcription factors. When oxidative stress augments the pressure on the intracellular environment, the effective reduction potential of redox pairs diminishes, and cell signaling shifts toward proinflammatory and proapoptotic signals, creating a vicious cycle between oxidative stress and neuroinflammation. In addition, electrophilic compounds derived from the oxidative cascade react with key protein thiols and interfere with redox signaling. This article reviews the relevant functional aspects of redox control during the neuroinflammatory process.
Collapse
Affiliation(s)
- Sergio Rosales-Corral
- Lab. Desarrollo-Envejecimiento, Enfermedades Neurodegenerativas, División de Neurociencias, Centro de Investigación Biomédica de Occidente (CIBO) del Instituto Mexicano del Seguro Social (IMSS) , Guadalajara, Jalisco. Mexico.
| | | | | | | | | |
Collapse
|
27
|
Selva J, Martínez SE, Buceta D, Rodríguez-Vázquez MJ, Blanco MC, López-Quintela MA, Egea G. Silver Sub-nanoclusters Electrocatalyze Ethanol Oxidation and Provide Protection against Ethanol Toxicity in Cultured Mammalian Cells. J Am Chem Soc 2010; 132:6947-54. [DOI: 10.1021/ja907988s] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Javier Selva
- Departament de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, Instituts d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) i de Nanociències i Nanotecnologia (IN2UB), Universitat de Barcelona, E-08036 Barcelona, Spain, and Laboratorio de Magnetismo y Nanotecnología (Nanomag), Instituto de Investigación Tecnológica, Universidad de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - Susana E. Martínez
- Departament de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, Instituts d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) i de Nanociències i Nanotecnologia (IN2UB), Universitat de Barcelona, E-08036 Barcelona, Spain, and Laboratorio de Magnetismo y Nanotecnología (Nanomag), Instituto de Investigación Tecnológica, Universidad de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - David Buceta
- Departament de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, Instituts d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) i de Nanociències i Nanotecnologia (IN2UB), Universitat de Barcelona, E-08036 Barcelona, Spain, and Laboratorio de Magnetismo y Nanotecnología (Nanomag), Instituto de Investigación Tecnológica, Universidad de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - María J. Rodríguez-Vázquez
- Departament de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, Instituts d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) i de Nanociències i Nanotecnologia (IN2UB), Universitat de Barcelona, E-08036 Barcelona, Spain, and Laboratorio de Magnetismo y Nanotecnología (Nanomag), Instituto de Investigación Tecnológica, Universidad de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - M. Carmen Blanco
- Departament de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, Instituts d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) i de Nanociències i Nanotecnologia (IN2UB), Universitat de Barcelona, E-08036 Barcelona, Spain, and Laboratorio de Magnetismo y Nanotecnología (Nanomag), Instituto de Investigación Tecnológica, Universidad de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - M. Arturo López-Quintela
- Departament de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, Instituts d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) i de Nanociències i Nanotecnologia (IN2UB), Universitat de Barcelona, E-08036 Barcelona, Spain, and Laboratorio de Magnetismo y Nanotecnología (Nanomag), Instituto de Investigación Tecnológica, Universidad de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - Gustavo Egea
- Departament de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, Instituts d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) i de Nanociències i Nanotecnologia (IN2UB), Universitat de Barcelona, E-08036 Barcelona, Spain, and Laboratorio de Magnetismo y Nanotecnología (Nanomag), Instituto de Investigación Tecnológica, Universidad de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| |
Collapse
|
28
|
Kierat RM, Thaler BMB, Krämer R. A fluorescent redox sensor with tuneable oxidation potential. Bioorg Med Chem Lett 2009; 20:1457-9. [PMID: 20100659 DOI: 10.1016/j.bmcl.2009.03.171] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Revised: 03/20/2009] [Accepted: 03/23/2009] [Indexed: 11/27/2022]
Abstract
A fluorescent redox sensor was prepared by attachment of hydroquinones to the fluorophore rhodamine B; fluorescence is reversibly modulated by hydroquinone-centered chemical redox reactions, and oxidation potential of the sensor is tuneable by variation of hydroquinone structure.
Collapse
Affiliation(s)
- Radoslaw M Kierat
- Anorganisches Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | | | | |
Collapse
|
29
|
Kemp M, Go YM, Jones DP. Nonequilibrium thermodynamics of thiol/disulfide redox systems: a perspective on redox systems biology. Free Radic Biol Med 2008; 44:921-37. [PMID: 18155672 PMCID: PMC2587159 DOI: 10.1016/j.freeradbiomed.2007.11.008] [Citation(s) in RCA: 413] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2007] [Revised: 09/28/2007] [Accepted: 11/14/2007] [Indexed: 01/18/2023]
Abstract
Understanding the dynamics of redox elements in biologic systems remains a major challenge for redox signaling and oxidative stress research. Central redox elements include evolutionarily conserved subsets of cysteines and methionines of proteins which function as sulfur switches and labile reactive oxygen species (ROS) and reactive nitrogen species (RNS) which function in redox signaling. The sulfur switches depend on redox environments in which rates of oxidation are balanced with rates of reduction through the thioredoxins, glutathione/glutathione disulfide, and cysteine/cystine redox couples. These central couples, which we term redox control nodes, are maintained at stable but nonequilibrium steady states, are largely independently regulated in different subcellular compartments, and are quasi-independent from each other within compartments. Disruption of the redox control nodes can differentially affect sulfur switches, thereby creating a diversity of oxidative stress responses. Systems biology provides approaches to address the complexity of these responses. In the present review, we summarize thiol/disulfide pathway, redox potential, and rate information as a basis for kinetic modeling of sulfur switches. The summary identifies gaps in knowledge especially related to redox communication between compartments, definition of redox pathways, and discrimination between types of sulfur switches. A formulation for kinetic modeling of GSH/GSSG redox control indicates that systems biology could encourage novel therapeutic approaches to protect against oxidative stress by identifying specific redox-sensitive sites which could be targeted for intervention.
Collapse
Affiliation(s)
- Melissa Kemp
- The Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta GA 30332
| | - Young-Mi Go
- Emory Clinical Biomarkers Laboratory and Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University, Atlanta GA 30322
| | - Dean P. Jones
- Emory Clinical Biomarkers Laboratory and Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University, Atlanta GA 30322
- Corresponding Author: Dr. Dean P. Jones, 205 Whitehead Research Center, Emory University, Atlanta, GA 30322, Phone: 404-727-5970; Fax; 404-712-2974; E-mail:
| |
Collapse
|
30
|
Schmitz T, Bravo-Osuna I, Vauthier C, Ponchel G, Loretz B, Bernkop-Schnürch A. Development and in vitro evaluation of a thiomer-based nanoparticulate gene delivery system. Biomaterials 2007; 28:524-31. [PMID: 16979757 DOI: 10.1016/j.biomaterials.2006.08.017] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2006] [Accepted: 08/11/2006] [Indexed: 01/19/2023]
Abstract
Chitosan-thiobutylamidine was developed and evaluated as a novel tool for gene delivery. The conjugate, displaying 299.1+/-11.5 micromol free thiol groups per gram polymer, formed coacervates with pDNA at a mean size of 125 nm and a zeta potential of +9 mV. Thiol groups, being susceptible for oxidation, were immobilised on the polymeric backbone of chitosan in order to introduce the property of extracellular stability and intracellular pDNA release by forming reversible disulfide bonds. The integrity of the new particles was compared to unmodified chitosan under simulated physiological conditions. Within 10h, pDNA was completely released from chitosan-DNA particles while only 12% were released from the thiomer-based particles. At pH 7, the amount of thiol groups significantly (p<0.05) decreased by more than 25% within 6h. In contrast, in a reducing environment as found intracellularly, chitosan-thiobutylamidine-DNA nanoparticles dissociated continuously, liberating approximately 50% of pDNA within 3h. Transfection studies performed in a Caco2 cell culture evinced the highest efficiency for chitosan-thiobutylamidine-DNA nanoparticles in combination with a glycerol shock solution. The combination of improved stability, enhanced pDNA release under reducing conditions, and higher transfection efficiency identifies chitosan-thiobutylamidine as a promising new vector for gene delivery.
Collapse
Affiliation(s)
- Thierry Schmitz
- Department of Pharmaceutical Technology, Faculty of Chemistry and Pharmacy, Institute of Pharmacy, Leopold-Franzens-University Innsbruck, Innrain 52, A 6020 Innsbruck, Austria
| | | | | | | | | | | |
Collapse
|