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Gandhi VV, Pal MK, Singh BG, Das RP, Wadawale AP, Dey S, Kunwar A. Deuterium labeling improves the therapeutic index of 3,3'-diselenodipropionic acid as an anticancer agent: insights from redox reactions. RSC Med Chem 2024; 15:2165-2178. [PMID: 38911162 PMCID: PMC11187547 DOI: 10.1039/d4md00105b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2024] [Accepted: 05/02/2024] [Indexed: 06/25/2024] Open
Abstract
3,3'-Diselenodipropionic acid (DSePA), a selenocystine derivative, has been previously reported as an oral supplement for anticancer/radio-modulation activities. The present study is focused on devising a strategy to synthesize and characterize the deuterated derivative of DSePA and on understanding the effect of deuteration on its therapeutic index by comparing its cytotoxicity in cancerous versus non-cancerous cell types. In this context, the synthesis of 3,3'-diselenodipropionic acid-D8 (D-DSePA) was accomplished in ∼42% yield. Further, the results clearly established that the deuteration of DSePA significantly reduced its cytotoxicity in non-cancerous cell types while retaining its cytotoxicity in cancerous cell lines. Together, D-DSePA displayed a ∼5-fold higher therapeutic index than the non-deuterated derivative for anticancer activity. The biochemical and NMR studies confirmed that the better biocompatibility of D-DSePA than its non-deuterated derivative in non-cancerous cells was due to its ability to undergo slower redox reactions and to cause lesser inhibition of intracellular redox enzymes.
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Affiliation(s)
- V V Gandhi
- Radiation and Photochemistry Division, Bhabha Atomic Research Centre Mumbai - 400085 India 91 22 25505151 91 22 25592352/25595399
- Homi Bhabha National Institute Anushaktinagar Mumbai - 400 094 India
| | - M K Pal
- Chemistry Division, Bhabha Atomic Research Centre Mumbai - 400085 India 91 22 25592589
| | - B G Singh
- Radiation and Photochemistry Division, Bhabha Atomic Research Centre Mumbai - 400085 India 91 22 25505151 91 22 25592352/25595399
- Homi Bhabha National Institute Anushaktinagar Mumbai - 400 094 India
| | - R P Das
- Radiation and Photochemistry Division, Bhabha Atomic Research Centre Mumbai - 400085 India 91 22 25505151 91 22 25592352/25595399
| | - A P Wadawale
- Chemistry Division, Bhabha Atomic Research Centre Mumbai - 400085 India 91 22 25592589
| | - S Dey
- Chemistry Division, Bhabha Atomic Research Centre Mumbai - 400085 India 91 22 25592589
- Homi Bhabha National Institute Anushaktinagar Mumbai - 400 094 India
| | - A Kunwar
- Radiation and Photochemistry Division, Bhabha Atomic Research Centre Mumbai - 400085 India 91 22 25505151 91 22 25592352/25595399
- Homi Bhabha National Institute Anushaktinagar Mumbai - 400 094 India
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2
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Zeisel L, Felber JG, Scholzen KC, Schmitt C, Wiegand AJ, Komissarov L, Arnér ESJ, Thorn-Seshold O. Piperazine-Fused Cyclic Disulfides Unlock High-Performance Bioreductive Probes of Thioredoxins and Bifunctional Reagents for Thiol Redox Biology. J Am Chem Soc 2024; 146:5204-5214. [PMID: 38358897 DOI: 10.1021/jacs.3c11153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
We report piperazine-fused six-membered-cyclic disulfides as redox substrates that unlock best-in-class bioreduction probes for live cell biology, since their self-immolation after reduction is unprecedentedly rapid. We develop scalable, diastereomerically pure, six-step syntheses that access four key cis- and trans-piperazine-fused cyclic dichalcogenides without chromatography. Fluorogenic redox probes using the disulfide piperazines are activated >100-fold faster than the prior art monoamines, allowing us to deconvolute reduction and cyclization rates during activation. The cis- and trans-fused diastereomers have remarkably different reductant specificities, which we trace back to piperazine boat/chair conformation effects: the cis-fused disulfide C-DiThia is activated only by strong vicinal dithiol reductants, but the trans-disulfide T-DiThia is activated even by moderate concentrations of monothiols such as GSH. Thus, in cellular applications, cis-disulfide probes selectively report on the reductive activity of the powerful thioredoxin proteins, while trans-disulfides are rapidly but promiscuously reactive. Finally, we showcase late-stage diversifications of the piperazine-disulfides, promising their broad applicability as redox-cleavable cores for probes and prodrugs that interface powerfully with cellular thiol/disulfide redox biology, for solid phase synthesis and purification, and for stimulus-responsive linkers in bifunctional reagents and antibody-drug conjugates - in addition to their dithiols' potential as high-performance reducing agents.
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Affiliation(s)
- Lukas Zeisel
- Department of Pharmacy, LMU Munich, Butenandtstr. 5-13, Munich 81377, Germany
| | - Jan G Felber
- Department of Pharmacy, LMU Munich, Butenandtstr. 5-13, Munich 81377, Germany
| | - Karoline C Scholzen
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm 17177, Sweden
| | - Carina Schmitt
- Department of Pharmacy, LMU Munich, Butenandtstr. 5-13, Munich 81377, Germany
| | - Alexander J Wiegand
- Department of Pharmacy, LMU Munich, Butenandtstr. 5-13, Munich 81377, Germany
| | - Leonid Komissarov
- Center for Molecular Modeling (CMM), Ghent University, Technologiepark-Zwijnaarde 46, Ghent 9052, Belgium
| | - Elias S J Arnér
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm 17177, Sweden
- Department of Selenoprotein Research, National Institute of Oncology, Budapest 1122, Hungary
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3
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Kreindl C, Soto-Alarcón SA, Hidalgo M, Riveros AL, Añazco C, Pulgar R, Porras O. Selenium Compounds Affect Differently the Cytoplasmic Thiol/Disulfide State in Dermic Fibroblasts and Improve Cell Migration by Interacting with the Extracellular Matrix. Antioxidants (Basel) 2024; 13:159. [PMID: 38397757 PMCID: PMC10886037 DOI: 10.3390/antiox13020159] [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: 12/14/2023] [Revised: 01/15/2024] [Accepted: 01/24/2024] [Indexed: 02/25/2024] Open
Abstract
Deficient wound healing is frequently observed in patients diagnosed with diabetes, a clinical complication that compromises mobility and leads to limb amputation, decreasing patient autonomy and family lifestyle. Fibroblasts are crucial for secreting the extracellular matrix (ECM) to pave the wound site for endothelial and keratinocyte regeneration. The biosynthetic pathways involved in collagen production and crosslinking are intimately related to fibroblast redox homeostasis. In this study, two sets of human dermic fibroblasts were cultured in normal (5 mM) and high (25 mM)-glucose conditions in the presence of 1 µM selenium, as sodium selenite (inorganic) and the two selenium amino acids (organic), Se-cysteine and Se-methionine, for ten days. We investigated the ultrastructural changes in the secreted ECM induced by these conditions using scanning electron microscopy (SEM). In addition, we evaluated the redox impact of these three compounds by measuring the basal state and real-time responses of the thiol-based HyPer biosensor expressed in the cytoplasm of these fibroblasts. Our results indicate that selenium compound supplementation pushed the redox equilibrium towards a more oxidative tone in both sets of fibroblasts, and this effect was independent of the type of selenium. The kinetic analysis of biosensor responses allowed us to identify Se-cysteine as the only compound that simultaneously improved the sensitivity to oxidative stimuli and augmented the disulfide bond reduction rate in high-glucose-cultured fibroblasts. The redox response profiles showed no clear association with the ultrastructural changes observed in matrix fibers secreted by selenium-treated fibroblasts. However, we found that selenium supplementation improved the ECM secreted by high-glucose-cultured fibroblasts according to endothelial migration assessed with a wound healing assay. Direct application of sodium selenite and Se-cysteine on purified collagen fibers subjected to glycation also improved cellular migration, suggesting that these selenium compounds avoid the undesired effect of glycation.
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Affiliation(s)
- Christine Kreindl
- Laboratory for Research in Functional Nutrition, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile, Santiago 7830490, Chile; (C.K.); (M.H.)
| | - Sandra A. Soto-Alarcón
- Department of Nutrition and Dietetics, Faculty of Health Sciences, Universidad Autónoma de Chile, Santiago 7500912, Chile;
| | - Miltha Hidalgo
- Laboratory for Research in Functional Nutrition, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile, Santiago 7830490, Chile; (C.K.); (M.H.)
| | - Ana L. Riveros
- Laboratorio de Nanobiotecnología y Nanotoxicología, Departamento de Química Farmacológica y Toxicológica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Sergio Livingston 1007, Santiago 8380492, Chile;
| | - Carolina Añazco
- Laboratorio de Bioquímica Nutricional, Escuela de Nutrición y Dietética, Facultad de Ciencias para el Cuidado de la Salud, Universidad San Sebastián, General Lagos #1190, Valdivia 5110773, Chile;
| | - Rodrigo Pulgar
- Laboratory of Genomics and Genetics of Biological Interactions, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago 7830490, Chile;
| | - Omar Porras
- Laboratory for Research in Functional Nutrition, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile, Santiago 7830490, Chile; (C.K.); (M.H.)
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4
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Chaudière J. Biological and Catalytic Properties of Selenoproteins. Int J Mol Sci 2023; 24:10109. [PMID: 37373256 DOI: 10.3390/ijms241210109] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 06/06/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023] Open
Abstract
Selenocysteine is a catalytic residue at the active site of all selenoenzymes in bacteria and mammals, and it is incorporated into the polypeptide backbone by a co-translational process that relies on the recoding of a UGA termination codon into a serine/selenocysteine codon. The best-characterized selenoproteins from mammalian species and bacteria are discussed with emphasis on their biological function and catalytic mechanisms. A total of 25 genes coding for selenoproteins have been identified in the genome of mammals. Unlike the selenoenzymes of anaerobic bacteria, most mammalian selenoenzymes work as antioxidants and as redox regulators of cell metabolism and functions. Selenoprotein P contains several selenocysteine residues and serves as a selenocysteine reservoir for other selenoproteins in mammals. Although extensively studied, glutathione peroxidases are incompletely understood in terms of local and time-dependent distribution, and regulatory functions. Selenoenzymes take advantage of the nucleophilic reactivity of the selenolate form of selenocysteine. It is used with peroxides and their by-products such as disulfides and sulfoxides, but also with iodine in iodinated phenolic substrates. This results in the formation of Se-X bonds (X = O, S, N, or I) from which a selenenylsulfide intermediate is invariably produced. The initial selenolate group is then recycled by thiol addition. In bacterial glycine reductase and D-proline reductase, an unusual catalytic rupture of selenium-carbon bonds is observed. The exchange of selenium for sulfur in selenoproteins, and information obtained from model reactions, suggest that a generic advantage of selenium compared with sulfur relies on faster kinetics and better reversibility of its oxidation reactions.
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Affiliation(s)
- Jean Chaudière
- CBMN (CNRS, UMR 5248), University of Bordeaux, 33600 Pessac, France
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5
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Zeisel L, Felber JG, Scholzen KC, Poczka L, Cheff D, Maier MS, Cheng Q, Shen M, Hall MD, Arnér ES, Thorn-Seshold J, Thorn-Seshold O. Selective cellular probes for mammalian thioredoxin reductase TrxR1: Rational design of RX1, a modular 1,2-thiaselenane redox probe. Chem 2022; 8:1493-1517. [PMID: 35936029 PMCID: PMC9351623 DOI: 10.1016/j.chempr.2022.03.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Quantifying the activity of key cellular redox players is crucial for understanding physiological homeostasis, and for targeting their perturbed states in pathologies including cancer and inflammatory diseases. However, cellularly-selective probes for oxidoreductase turnover are sorely lacking. We rationally developed the first probes that selectively target the mammalian selenoprotein thioredoxin reductase (TrxR), using a cyclic selenenylsulfide oriented to harness TrxR's unique selenolthiol chemistry while resisting the cellular monothiol background. Lead probe RX1 had excellent TrxR1-selective performance in cells, cross-validated by knockout, selenium starvation, knock-in, and chemical inhibitors. Its background-free fluorogenicity enabled us to perform the first quantitative high-throughput live cell screen for TrxR1 inhibitors, which indicated that tempered SNAr electrophiles may be more selective TrxR drugs than the classical electrophiles used hitherto. The RX1 design thus sets the stage for in vivo imaging of the activity of this key oxidoreductase in health and disease, and can also drive TrxR1-inhibitor drug design.
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The mammalian-type thioredoxin reductase 1 confers a high-light tolerance to the green alga Chlamydomonas reinhardtii. Biochem Biophys Res Commun 2022; 596:97-103. [PMID: 35121375 DOI: 10.1016/j.bbrc.2022.01.088] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 01/23/2022] [Indexed: 11/21/2022]
Abstract
Reactive oxygen species (ROS) can both act as a poison causing cell death and important signaling molecules among various organisms. Photosynthetic organisms inevitably produce ROS, making the appropriate elimination of ROS an essential strategy for survival. Interestingly, the unicellular green alga Chlamydomonas reinhardtii expresses a mammalian form of thioredoxin reductase, TR1, which functions as a ROS scavenger in animal cells. To investigate the properties of TR1 in C. reinhardtii, we generated TR1 knockout strains using CRISPR/Cas9-based genome editing. We found a reduced tolerance to high-light and ROS stresses in the TR1 knockout strains compared to the parental strain. In addition, the regulation of phototactic orientation, known to be regulated by ROS, was affected in the knockout strains. These results suggest that TR1 contributes to a ROS-scavenging pathway in C. reinhardtii.
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Abstract
The cytosolic selenoprotein thioredoxin reductase 1 (TrxR1, TXNRD1), and to some extent mitochondrial TrxR2 (TXNRD2), can be inhibited by a wide range of electrophilic compounds. Many such compounds also yield cytotoxicity toward cancer cells in culture or in mouse models, and most compounds are likely to irreversibly modify the easily accessible selenocysteine residue in TrxR1, thereby inhibiting its normal activity to reduce cytosolic thioredoxin (Trx1, TXN) and other substrates of the enzyme. This leads to an oxidative challenge. In some cases, the inhibited forms of TrxR1 are not catalytically inert and are instead converted to prooxidant NADPH oxidases, named SecTRAPs, thus further aggravating the oxidative stress, particularly in cells expressing higher levels of the enzyme. In this review, the possible molecular and cellular consequences of these effects are discussed in relation to cancer therapy, with a focus on outstanding questions that should be addressed if targeted TrxR1 inhibition is to be further developed for therapeutic use. Expected final online publication date for the Annual Review of Pharmacology and Toxicology, Volume 62 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Radosveta Gencheva
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden;
| | - Elias S J Arnér
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden; .,Department of Selenoprotein Research, National Institute of Oncology, Budapest 1122, Hungary
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8
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Ayoup MS, Abu-Serie MM, Abdel-Hamid H, Teleb M. Beyond direct Nrf2 activation; reinvestigating 1,2,4-oxadiazole scaffold as a master key unlocking the antioxidant cellular machinery for cancer therapy. Eur J Med Chem 2021; 220:113475. [PMID: 33901898 DOI: 10.1016/j.ejmech.2021.113475] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 03/26/2021] [Accepted: 04/11/2021] [Indexed: 01/22/2023]
Abstract
Harnessing the antioxidant cellular machinery has sparked considerable interest as an efficient anticancer strategy. Activating Nrf2, the master switch of the cellular redox system, suppresses ROS, alleviates oxidative stress, and halts cancer progression. 1,2,4-oxadiazoles are iconic direct Nrf2 activators that disrupt Nrf2 interaction with its endogenous repressor Keap1. This study introduces rationally designed 1,2,4-oxadiazole derivatives that inhibit other Nrf2 suppressors (TrxR1, IKKα, and NF-kB) thus enhancing Nrf2 activation for preventing oxidative stress and carcinogenesis. Preliminary screening showed that the phenolic oxadiazoles 11, 15, and 19 were comparable to ascorbic acid (ROS scavenging) and EDTA (iron chelation), and superior to doxorubicin against HepG-2, MDA-MB231, and Caco-2 cells. They suppressed ROS by 3 folds and activated Nrf2 by 2 folds in HepG-2 cells. Mechanistically, they inhibited TrxR1 (IC50; 13.19, 17.89, and 9.21 nM) and IKKα (IC50; 11.0, 15.94, and 19.58 nM), and downregulated NF-κB (7.6, 1.4 and 1.9 folds in HepG-2), respectively. They inhibited NADPH oxidase (IC50; 16.4, 21.94, and 10.71 nM, respectively) that potentiates their antioxidant activities. Docking studies predicted their important structural features. Finally, they recorded drug-like in silico physicochemical properties, ADMET, and ligand efficiency metrics.
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Affiliation(s)
- Mohammed Salah Ayoup
- Chemistry Department, Faculty of Science, Alexandria University, Alexandria, 21321, Egypt.
| | - Marwa M Abu-Serie
- Medical Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technological Applications, SRTA-City, Egypt
| | - Hamida Abdel-Hamid
- Chemistry Department, Faculty of Science, Alexandria University, Alexandria, 21321, Egypt
| | - Mohamed Teleb
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Alexandria University, Alexandria, 21521, Egypt.
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9
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Zhou R, Xiang C, Cao G, Xu H, Zhang Y, Yang H, Zhang J. Berberine accelerated wound healing by restoring TrxR1/JNK in diabetes. Clin Sci (Lond) 2021; 135:613-627. [PMID: 33491733 DOI: 10.1042/cs20201145] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 01/14/2021] [Accepted: 01/25/2021] [Indexed: 12/17/2022]
Abstract
The high disability, mortality and morbidity of diabetic ulcers make it urgent to explore effective strategies for diabetic wound repair. TrxR1 plays a vital role in regulating redox homeostasis in various pathologies. In the present study, the effect of berberine (BBR) on diabetic wounds was investigated in streptozotocin (STZ)-induced diabetic rats and a high glucose (HG)-induced cell model, and the mechanism of BBR on TrxR1 was elucidated. BBR treatment remarkably accelerated wound healing and enhanced extracellular matrix (ECM) synthesis and significantly inhibited HG-induced HaCaT cell damage. Further analysis indicated that BBR activated TrxR1, suppressed its downstream JNK signaling, thereby inhibiting oxidative stress and apoptosis, promoted cell proliferation, down-regulated matrix metalloproteinase (MMP) 9 (MMP9) and up-regulated transforming growth factor-β1 (TGF-β1) and tissue inhibitors of MMP 1 (TIMP1), resulting in accelerated wound healing. Importantly, the enhancement of BBR on wound repair was further abolished by TrxR1 inhibitor. Moreover, in diabetic wounds induced by a combination of STZ injection and high-fat diet, BBR significantly increased wound closure rate and TrxR1 expression, and this was reversed by TrxR1 inhibitor. These data indicated that topical BBR treatment accelerated diabetic wound healing by activating TrxR1. Targeting TrxR1 may be a novel, effective strategy for restoring redox homeostasis and promoting diabetic wound healing.
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Affiliation(s)
- Rui Zhou
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Changpei Xiang
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Guangzhao Cao
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - He Xu
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Yi Zhang
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Hongjun Yang
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Jingjing Zhang
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
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Wang H, Jiang H, Corbet C, de Mey S, Law K, Gevaert T, Feron O, De Ridder M. Piperlongumine increases sensitivity of colorectal cancer cells to radiation: Involvement of ROS production via dual inhibition of glutathione and thioredoxin systems. Cancer Lett 2019; 450:42-52. [PMID: 30790679 DOI: 10.1016/j.canlet.2019.02.034] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 02/08/2019] [Accepted: 02/14/2019] [Indexed: 01/19/2023]
Abstract
Piperlongumine (PL), naturally synthesized in long pepper, is known to selectively kill tumor cells via perturbation of reactive oxygen species (ROS) homeostasis. ROS are the primary effector molecules of radiation, and increase of ROS production by pharmacological modulation is known to enhance radioresponse. We therefore investigated the radiosensitizing effect of PL in colorectal cancer cells (CT26 and DLD-1) and CT26 tumor-bearing mice. Firstly, we found that PL induced excessive production of ROS due to depletion of glutathione and inhibition of thioredoxin reductase. Secondly, PL enhanced both the intrinsic and hypoxic radiosensitivity of tumor cells, linked to ROS-mediated increase of DNA damage, G2/M cell cycle arrest, and inhibition of cellular respiration. Finally, the radiosensitizing effect of PL was verified in vivo. PL improved the tumor response to both single and fractionated radiation, resulting in a significant increase of survival rate of tumor-bearing mice, while it was ineffective on its own. In line with in vitro findings, enhanced radioresponse is associated with inhibition of antioxidant systems. In conclusion, our results suggest that PL could be a potential radiosensitizer in colorectal cancer.
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Affiliation(s)
- Hui Wang
- Department of Radiotherapy, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Heng Jiang
- Department of Radiotherapy, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Cyril Corbet
- Pole of Pharmacology and Therapeutics (FATH), Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain, Brussels, Belgium
| | - Sven de Mey
- Department of Radiotherapy, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Kalun Law
- Department of Radiotherapy, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Thierry Gevaert
- Department of Radiotherapy, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Olivier Feron
- Pole of Pharmacology and Therapeutics (FATH), Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain, Brussels, Belgium
| | - Mark De Ridder
- Department of Radiotherapy, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels, Belgium.
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11
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Katsu-Jiménez Y, Vázquez-Calvo C, Maffezzini C, Halldin M, Peng X, Freyer C, Wredenberg A, Giménez-Cassina A, Wedell A, Arnér ESJ. Absence of TXNIP in Humans Leads to Lactic Acidosis and Low Serum Methionine Linked to Deficient Respiration on Pyruvate. Diabetes 2019; 68:709-723. [PMID: 30755400 DOI: 10.2337/db18-0557] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 01/21/2019] [Indexed: 11/13/2022]
Abstract
Thioredoxin-interacting protein (TXNIP) is an α-arrestin that can bind to and inhibit the antioxidant protein thioredoxin (TXN). TXNIP expression is induced by glucose and promotes β-cell apoptosis in the pancreas, and deletion of its gene in mouse models protects against diabetes. TXNIP is currently studied as a potential new target for antidiabetic drug therapy. In this study, we describe a family with a mutation in the TXNIP gene leading to nondetectable expression of TXNIP protein. Symptoms of affected family members include lactic acidosis and low serum methionine levels. Using patient-derived TXNIP-deficient fibroblasts and myoblasts, we show that oxidative phosphorylation is impaired in these cells when given glucose and pyruvate but normalized with malate. Isolated mitochondria from these cells appear to have normal respiratory function. The cells also display a transcriptional pattern suggestive of a high basal activation of the Nrf2 transcription factor. We conclude that a complete lack of TXNIP in human is nonlethal and leads to specific metabolic distortions that are, at least in part, linked to a deficient respiration on pyruvate. The results give important insights into the impact of TXNIP in humans and thus help to further advance the development of antidiabetic drugs targeting this protein.
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Affiliation(s)
- Yurika Katsu-Jiménez
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Carmela Vázquez-Calvo
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Camilla Maffezzini
- Division of Molecular Metabolism, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Maria Halldin
- Department of Women's and Children's Health, Akademiska University Hospital, Uppsala, Sweden
| | - Xiaoxiao Peng
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Christoph Freyer
- Division of Molecular Metabolism, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Anna Wredenberg
- Division of Molecular Metabolism, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Alfredo Giménez-Cassina
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Department of Molecular Biology, Centro de Biología Molecular "Severo Ochoa," Universidad Autónoma de Madrid, Madrid, Spain
| | - Anna Wedell
- Department of Molecular Medicine and Surgery, Science for Life Laboratory, Karolinska Institutet, Stockholm, Sweden
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Elias S J Arnér
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
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12
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The thioredoxin-1 system is essential for fueling DNA synthesis during T-cell metabolic reprogramming and proliferation. Nat Commun 2018; 9:1851. [PMID: 29749372 PMCID: PMC5945637 DOI: 10.1038/s41467-018-04274-w] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 04/17/2018] [Indexed: 01/05/2023] Open
Abstract
The thioredoxin-1 (Trx1) system is an important contributor to cellular redox balance and is a sensor of energy and glucose metabolism. Here we show critical c-Myc-dependent activation of the Trx1 system during thymocyte and peripheral T-cell proliferation, but repression during T-cell quiescence. Deletion of thioredoxin reductase-1 (Txnrd1) prevents expansion the CD4−CD8− thymocyte population, whereas Txnrd1 deletion in CD4+CD8+ thymocytes does not affect further maturation and peripheral homeostasis of αβT cells. However, Txnrd1 is critical for expansion of the activated T-cell population during viral and parasite infection. Metabolomics show that TrxR1 is essential for the last step of nucleotide biosynthesis by donating reducing equivalents to ribonucleotide reductase. Impaired availability of 2′-deoxyribonucleotides induces the DNA damage response and cell cycle arrest of Txnrd1-deficient T cells. These results uncover a pivotal function of the Trx1 system in metabolic reprogramming of thymic and peripheral T cells and provide a rationale for targeting Txnrd1 in T-cell leukemia. Thioredoxin (Trx), Trx reductase, Txnip and NADPH together comprise the Trx system. Here the authors make a T cell-specific thioredoxin reductase-1 knockout mouse to show how this system reprograms cellular metabolism to enable T cell development, proliferation and responses.
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13
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Zhang J, Zhang B, Li X, Han X, Liu R, Fang J. Small molecule inhibitors of mammalian thioredoxin reductase as potential anticancer agents: An update. Med Res Rev 2018; 39:5-39. [DOI: 10.1002/med.21507] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 04/11/2018] [Accepted: 04/12/2018] [Indexed: 12/17/2022]
Affiliation(s)
- Junmin Zhang
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering; Lanzhou University; Lanzhou China
- School of Pharmacy; Lanzhou University; Lanzhou China
| | - Baoxin Zhang
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering; Lanzhou University; Lanzhou China
| | - Xinming Li
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering; Lanzhou University; Lanzhou China
| | - Xiao Han
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering; Lanzhou University; Lanzhou China
| | - Ruijuan Liu
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering; Lanzhou University; Lanzhou China
- School of Pharmacy; Lanzhou University; Lanzhou China
| | - Jianguo Fang
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering; Lanzhou University; Lanzhou China
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14
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Prigge JR, Coppo L, Martin SS, Ogata F, Miller CG, Bruschwein MD, Orlicky DJ, Shearn CT, Kundert JA, Lytchier J, Herr AE, Mattsson Å, Taylor MP, Gustafsson TN, Arnér ESJ, Holmgren A, Schmidt EE. Hepatocyte Hyperproliferation upon Liver-Specific Co-disruption of Thioredoxin-1, Thioredoxin Reductase-1, and Glutathione Reductase. Cell Rep 2018; 19:2771-2781. [PMID: 28658624 PMCID: PMC5730093 DOI: 10.1016/j.celrep.2017.06.019] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 05/16/2017] [Accepted: 06/02/2017] [Indexed: 12/21/2022] Open
Abstract
Energetic nutrients are oxidized to sustain high intracellular NADPH/NADP+ ratios. NADPH-dependent reduction of thioredoxin-1 (Trx1) disulfide and glutathione disulfide by thioredoxin reductase-1 (TrxR1) and glutathione reductase (Gsr), respectively, fuels antioxidant systems and deoxyribonucleotide synthesis. Mouse livers lacking both TrxR1 and Gsr sustain these essential activities using an NADPH-independent methionine-consuming pathway; however, it remains unclear how this reducing power is distributed. Here, we show that liver-specific co-disruption of the genes encoding Trx1, TrxR1, and Gsr (triple-null) causes dramatic hepatocyte hyperproliferation. Thus, even in the absence of Trx1, methionine-fueled glutathione production supports hepatocyte S phase deoxyribonucleotide production. Also, Trx1 in the absence of TrxR1 provides a survival advantage to cells under hyperglycemic stress, suggesting that glutathione, likely via glutaredoxins, can reduce Trx1 disulfide in vivo. In triple-null livers like in many cancers, deoxyribonucleotide synthesis places a critical yet relatively low-volume demand on these reductase systems, thereby favoring high hepatocyte turnover over sustained hepatocyte integrity.
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Affiliation(s)
- Justin R Prigge
- Microbiology & Immunology, Montana State University, Bozeman, MT 59718, USA
| | - Lucia Coppo
- Division of Biochemistry, Medical Biochemistry & Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Sebastin S Martin
- Division of Biochemistry, Medical Biochemistry & Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Fernando Ogata
- Division of Biochemistry, Medical Biochemistry & Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Colin G Miller
- Microbiology & Immunology, Montana State University, Bozeman, MT 59718, USA
| | | | - David J Orlicky
- Department of Pathology, University of Colorado Anschutz Medical Center, Denver, CO 80045, USA
| | - Colin T Shearn
- Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Center, Denver, CO 80045, USA
| | - Jean A Kundert
- Microbiology & Immunology, Montana State University, Bozeman, MT 59718, USA
| | - Julia Lytchier
- Division of Biochemistry, Medical Biochemistry & Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Alix E Herr
- Microbiology & Immunology, Montana State University, Bozeman, MT 59718, USA
| | - Åse Mattsson
- Division of Biochemistry, Medical Biochemistry & Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Matthew P Taylor
- Microbiology & Immunology, Montana State University, Bozeman, MT 59718, USA
| | - Tomas N Gustafsson
- Division of Biochemistry, Medical Biochemistry & Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden; Department of Clinical Microbiology, Clinical Bacteriology, Sunderby Research Unit, Umeå University, 901 85 Umeå, Sweden
| | - Elias S J Arnér
- Division of Biochemistry, Medical Biochemistry & Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Arne Holmgren
- Division of Biochemistry, Medical Biochemistry & Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Edward E Schmidt
- Microbiology & Immunology, Montana State University, Bozeman, MT 59718, USA.
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15
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Stafford WC, Peng X, Olofsson MH, Zhang X, Luci DK, Lu L, Cheng Q, Trésaugues L, Dexheimer TS, Coussens NP, Augsten M, Ahlzén HSM, Orwar O, Östman A, Stone-Elander S, Maloney DJ, Jadhav A, Simeonov A, Linder S, Arnér ESJ. Irreversible inhibition of cytosolic thioredoxin reductase 1 as a mechanistic basis for anticancer therapy. Sci Transl Med 2018; 10:eaaf7444. [PMID: 29444979 PMCID: PMC7059553 DOI: 10.1126/scitranslmed.aaf7444] [Citation(s) in RCA: 133] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 02/01/2017] [Accepted: 12/14/2017] [Indexed: 12/25/2022]
Abstract
Cancer cells adapt to their inherently increased oxidative stress through activation of the glutathione (GSH) and thioredoxin (TXN) systems. Inhibition of both of these systems effectively kills cancer cells, but such broad inhibition of antioxidant activity also kills normal cells, which is highly unwanted in a clinical setting. We therefore evaluated targeting of the TXN pathway alone and, more specifically, selective inhibition of the cytosolic selenocysteine-containing enzyme TXN reductase 1 (TXNRD1). TXNRD1 inhibitors were discovered in a large screening effort and displayed increased specificity compared to pan-TXNRD inhibitors, such as auranofin, that also inhibit the mitochondrial enzyme TXNRD2 and additional targets. For our lead compounds, TXNRD1 inhibition correlated with cancer cell cytotoxicity, and inhibitor-triggered conversion of TXNRD1 from an antioxidant to a pro-oxidant enzyme correlated with corresponding increases in cellular production of H2O2 In mice, the most specific TXNRD1 inhibitor, here described as TXNRD1 inhibitor 1 (TRi-1), impaired growth and viability of human tumor xenografts and syngeneic mouse tumors while having little mitochondrial toxicity and being better tolerated than auranofin. These results display the therapeutic anticancer potential of irreversibly targeting cytosolic TXNRD1 using small molecules and present potent and selective TXNRD1 inhibitors. Given the pronounced up-regulation of TXNRD1 in several metastatic malignancies, it seems worthwhile to further explore the potential benefit of specific irreversible TXNRD1 inhibitors for anticancer therapy.
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Affiliation(s)
- William C Stafford
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE 171 77 Stockholm, Sweden
- Oblique Therapeutics AB, SE 413 46 Gothenburg, Sweden
| | - Xiaoxiao Peng
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Maria Hägg Olofsson
- Department of Oncology-Pathology, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Xiaonan Zhang
- Department of Oncology-Pathology, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Diane K Luci
- NIH Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20892-4874, USA
| | - Li Lu
- Karolinska Experimental Research and Imaging Center, Karolinska University Hospital, SE 171 76 Stockholm, Sweden
| | - Qing Cheng
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Lionel Trésaugues
- Division of Biophysics, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Thomas S Dexheimer
- NIH Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20892-4874, USA
| | - Nathan P Coussens
- NIH Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20892-4874, USA
| | - Martin Augsten
- Department of Oncology-Pathology, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Hanna-Stina Martinsson Ahlzén
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Owe Orwar
- Oblique Therapeutics AB, SE 413 46 Gothenburg, Sweden
- Department of Physiology and Pharmacology, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Arne Östman
- Department of Oncology-Pathology, Karolinska Institutet, SE 171 77 Stockholm, Sweden
- University of Bergen, Postboks 7804, N-5020 Bergen, Norway
| | - Sharon Stone-Elander
- Department of Neuroradiology, Positron Emission Tomography Radiochemistry, Karolinska University Hospital, SE 171 76 Stockholm, Sweden
- Department of Clinical Neurosciences, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - David J Maloney
- NIH Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20892-4874, USA
| | - Ajit Jadhav
- NIH Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20892-4874, USA
| | - Anton Simeonov
- NIH Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20892-4874, USA
| | - Stig Linder
- Department of Oncology-Pathology, Karolinska Institutet, SE 171 77 Stockholm, Sweden
- Division of Drug Research, Department of Medicine and Health, Linköping University, SE 581 83 Linköping, Sweden
| | - Elias S J Arnér
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE 171 77 Stockholm, Sweden.
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16
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Dagnell M, Schmidt EE, Arnér ESJ. The A to Z of modulated cell patterning by mammalian thioredoxin reductases. Free Radic Biol Med 2018; 115:484-496. [PMID: 29278740 PMCID: PMC5771652 DOI: 10.1016/j.freeradbiomed.2017.12.029] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 12/16/2017] [Accepted: 12/21/2017] [Indexed: 12/12/2022]
Abstract
Mammalian thioredoxin reductases (TrxRs) are selenocysteine-containing proteins (selenoproteins) that propel a large number of functions through reduction of several substrates including the active site disulfide of thioredoxins (Trxs). Well-known enzymatic systems that in turn are supported by Trxs and TrxRs include deoxyribonucleotide synthesis through ribonucleotide reductase, antioxidant defense through peroxiredoxins and methionine sulfoxide reductases, and redox modulation of a number of transcription factors. Although these functions may be essential for cells due to crucial roles in maintenance of cell viability and proliferation, findings during the last decade reveal that mammals have major redundancy in their cellular reductive systems. The synthesis of glutathione (GSH) and reductive functions of GSH-dependent pathways typically act in parallel with Trx-dependent pathways, with only one of these systems often being sufficient to support viability. Importantly, this does not imply that a modulation of the Trx system will remain without consequences, even when GSH-dependent pathways remain functional. As suggested by several recent findings, the Trx system in general and the TrxRs in particular, function as key regulators of signaling pathways. In this review article we will discuss findings that collectively suggest that modulation in mammalian systems of cytosolic TrxR1 (TXNRD1) or mitochondrial TrxR2 (TXNRD2) influence cell patterning and cellular stress responses. Effects of lower activities include increased adipogenesis, insulin responsiveness, glycogen accumulation, hyperproliferation, and distorted embryonic development, while increased activities correlate with decreased proliferation and extended lifespan, as well as worse cancer prognosis. The molecular mechanisms that underlie these diverse effects, involving regulation of protein phosphorylation cascades and of key transcription factors that guide cellular differentiation pathways, will be discussed. We conclude that the selenium-dependent oxidoreductases TrxR1 and TrxR2 should be considered as key components of signaling pathways that control cell differentiation and cellular stress responses.
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Affiliation(s)
- Markus Dagnell
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77, Stockholm, Sweden
| | - Edward E Schmidt
- Microbiology & Immunology, Montana State University, Bozeman, MT 59718, USA
| | - Elias S J Arnér
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77, Stockholm, Sweden.
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17
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Ingold I, Berndt C, Schmitt S, Doll S, Poschmann G, Buday K, Roveri A, Peng X, Porto Freitas F, Seibt T, Mehr L, Aichler M, Walch A, Lamp D, Jastroch M, Miyamoto S, Wurst W, Ursini F, Arnér ES, Fradejas-Villar N, Schweizer U, Zischka H, Friedmann Angeli JP, Conrad M. Selenium Utilization by GPX4 Is Required to Prevent Hydroperoxide-Induced Ferroptosis. Cell 2018; 172:409-422.e21. [DOI: 10.1016/j.cell.2017.11.048] [Citation(s) in RCA: 458] [Impact Index Per Article: 76.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 10/16/2017] [Accepted: 11/28/2017] [Indexed: 01/11/2023]
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18
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Dagnell M, Pace PE, Cheng Q, Frijhoff J, Östman A, Arnér ESJ, Hampton MB, Winterbourn CC. Thioredoxin reductase 1 and NADPH directly protect protein tyrosine phosphatase 1B from inactivation during H 2O 2 exposure. J Biol Chem 2017; 292:14371-14380. [PMID: 28684416 DOI: 10.1074/jbc.m117.793745] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 06/26/2017] [Indexed: 02/06/2023] Open
Abstract
Regulation of growth factor signaling involves reversible inactivation of protein tyrosine phosphatases (PTPs) through the oxidation and reduction of their active site cysteine. However, there is limited mechanistic understanding of these redox events and their co-ordination in the presence of cellular antioxidant networks. Here we investigated interactions between PTP1B and the peroxiredoxin 2 (Prx2)/thioredoxin 1 (Trx1)/thioredoxin reductase 1 (TrxR1) network. We found that Prx2 becomes oxidized in PDGF-treated fibroblasts, but only when TrxR1 has first been inhibited. Using purified proteins, we also found that PTP1B is relatively insensitive to inactivation by H2O2 but found no evidence for a relay mechanism in which Prx2 or Trx1 facilitates PTP1B oxidation. Instead, these proteins prevented PTP1B inactivation by H2O2 Intriguingly, we discovered that TrxR1/NADPH directly protects PTP1B from inactivation when present during the H2O2 exposure. This protection was dependent on the concentration of TrxR1 and independent of Trx1 and Prx2. The protection was blocked by auranofin and required an intact selenocysteine residue in TrxR1. This activity likely involves reduction of the sulfenic acid intermediate form of PTP1B by TrxR1 and is therefore distinct from the previously described reactivation of end-point oxidized PTP1B, which requires both Trx1 and TrxR1. The ability of TrxR1 to directly reduce an oxidized phosphatase is a novel activity that can help explain previously observed increases in PTP1B oxidation and PDGF receptor phosphorylation in TrxR1 knockout cells. The activity of TrxR1 is therefore of potential relevance for understanding the mechanisms of redox regulation of growth factor signaling pathways.
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Affiliation(s)
- Markus Dagnell
- From the Centre for Free Radical Research, Department of Pathology, University of Otago, Christchurch 8041, New Zealand.,the Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Paul E Pace
- From the Centre for Free Radical Research, Department of Pathology, University of Otago, Christchurch 8041, New Zealand
| | - Qing Cheng
- the Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Jeroen Frijhoff
- the Faculty of Health, Medicine and Life Sciences, Cardiovascular Research Institute Maastricht University, 6229 ER Maastricht, The Netherlands, and
| | - Arne Östman
- the Department of Oncology and Pathology, Cancer Center Karolinska, Karolinska Institutet, 171 76 Stockholm, Sweden
| | - Elias S J Arnér
- the Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Mark B Hampton
- From the Centre for Free Radical Research, Department of Pathology, University of Otago, Christchurch 8041, New Zealand
| | - Christine C Winterbourn
- From the Centre for Free Radical Research, Department of Pathology, University of Otago, Christchurch 8041, New Zealand,
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19
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Kudin AP, Baron G, Zsurka G, Hampel KG, Elger CE, Grote A, Weber Y, Lerche H, Thiele H, Nürnberg P, Schulz H, Ruppert AK, Sander T, Cheng Q, Arnér ES, Schomburg L, Seeher S, Fradejas-Villar N, Schweizer U, Kunz WS. Homozygous mutation in TXNRD1 is associated with genetic generalized epilepsy. Free Radic Biol Med 2017; 106:270-277. [PMID: 28232204 DOI: 10.1016/j.freeradbiomed.2017.02.040] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 02/10/2017] [Accepted: 02/20/2017] [Indexed: 11/16/2022]
Abstract
Increased oxidative stress has been widely implicated in the pathogenesis in various forms of human epilepsy. Here, we report a homozygous mutation in TXNRD1 (thioredoxin reductase 1) in a family with genetic generalized epilepsy. TXNRD1 is an essential selenium-containing enzyme involved in detoxification of reactive oxygen species (ROS) and redox signaling. The TXNRD1 mutation p.Pro190Leu affecting a highly conserved amino acid residue was identified by whole-exome sequencing of blood DNA from the index patient. The detected mutation and its segregation within the family - all siblings of the index patient were homozygous and the parents heterozygous - were confirmed by Sanger sequencing. TXNRD1 activity was determined in subcellular fractions from a skeletal muscle biopsy and skin fibroblasts of the index patient and the expression levels of the mutated protein were assessed by 75Se labeling and Western blot analysis. As result of the mutation, the activity of TXNRD1 was reduced in the patient's fibroblasts and skeletal muscle (to 34±3% and 16±8% of controls, respectively). In fibroblasts, we detected reduced 75Se-labeling of the enzyme (41±3% of controls). An in-depth in vitro kinetic analysis of the recombinant mutated TXNRD1 indicated 30-40% lowered kcat/Se values. Therefore, a reduced activity of the enzyme in the patient's tissue samples is explained by (i) lower enzyme turnover and (ii) reduced abundance of the mutated enzyme as confirmed by Western blotting and 75Se labeling. The mutant fibroblasts were also found to be less resistant to a hydrogen peroxide challenge. Our data agree with a potential role of insufficient ROS detoxification for disease manifestation in genetic generalized epilepsy.
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Affiliation(s)
- Alexei P Kudin
- Department of Epileptology and Life & Brain Center, University of Bonn, Bonn, Germany.
| | - Gregor Baron
- Department of Epileptology and Life & Brain Center, University of Bonn, Bonn, Germany.
| | - Gábor Zsurka
- Department of Epileptology and Life & Brain Center, University of Bonn, Bonn, Germany.
| | - Kevin G Hampel
- Department of Epileptology and Life & Brain Center, University of Bonn, Bonn, Germany.
| | - Christian E Elger
- Department of Epileptology and Life & Brain Center, University of Bonn, Bonn, Germany.
| | - Alexander Grote
- Department of Neurosurgery, University of Bonn, Bonn, Germany.
| | - Yvonne Weber
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.
| | - Holger Thiele
- Cologne Center for Genomics, University of Cologne, Cologne, Germany.
| | - Peter Nürnberg
- Cologne Center for Genomics, University of Cologne, Cologne, Germany.
| | - Herbert Schulz
- Cologne Center for Genomics, University of Cologne, Cologne, Germany.
| | | | - Thomas Sander
- Cologne Center for Genomics, University of Cologne, Cologne, Germany.
| | - Qing Cheng
- Division of Biochemistry, Dept. Medical Biochemistry and Biophysics (MBB), Karolinska Institutet, Stockholm, Sweden.
| | - Elias Sj Arnér
- Division of Biochemistry, Dept. Medical Biochemistry and Biophysics (MBB), Karolinska Institutet, Stockholm, Sweden.
| | - Lutz Schomburg
- Institute of Experimental Endocrinology, Charité-Universitätsmedizin, Berlin, Germany.
| | - Sandra Seeher
- Institut für Biochemie und Molekularbiologie, Rheinische Friedrich-Wilhelms-Universität Bonn, Germany.
| | - Noelia Fradejas-Villar
- Institut für Biochemie und Molekularbiologie, Rheinische Friedrich-Wilhelms-Universität Bonn, Germany.
| | - Ulrich Schweizer
- Institut für Biochemie und Molekularbiologie, Rheinische Friedrich-Wilhelms-Universität Bonn, Germany.
| | - Wolfram S Kunz
- Department of Epileptology and Life & Brain Center, University of Bonn, Bonn, Germany.
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20
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Wojtowicz EE, Lechman ER, Hermans KG, Schoof EM, Wienholds E, Isserlin R, van Veelen PA, Broekhuis MJC, Janssen GMC, Trotman-Grant A, Dobson SM, Krivdova G, Elzinga J, Kennedy J, Gan OI, Sinha A, Ignatchenko V, Kislinger T, Dethmers-Ausema B, Weersing E, Alemdehy MF, de Looper HWJ, Bader GD, Ritsema M, Erkeland SJ, Bystrykh LV, Dick JE, de Haan G. Ectopic miR-125a Expression Induces Long-Term Repopulating Stem Cell Capacity in Mouse and Human Hematopoietic Progenitors. Cell Stem Cell 2016; 19:383-96. [PMID: 27424784 DOI: 10.1016/j.stem.2016.06.008] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 04/01/2016] [Accepted: 06/15/2016] [Indexed: 12/25/2022]
Abstract
Umbilical cord blood (CB) is a convenient and broadly used source of hematopoietic stem cells (HSCs) for allogeneic stem cell transplantation. However, limiting numbers of HSCs remain a major constraint for its clinical application. Although one feasible option would be to expand HSCs to improve therapeutic outcome, available protocols and the molecular mechanisms governing the self-renewal of HSCs are unclear. Here, we show that ectopic expression of a single microRNA (miRNA), miR-125a, in purified murine and human multipotent progenitors (MPPs) resulted in increased self-renewal and robust long-term multi-lineage repopulation in transplanted recipient mice. Using quantitative proteomics and western blot analysis, we identified a restricted set of miR-125a targets involved in conferring long-term repopulating capacity to MPPs in humans and mice. Our findings offer the innovative potential to use MPPs with enhanced self-renewal activity to augment limited sources of HSCs to improve clinical protocols.
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Affiliation(s)
- Edyta E Wojtowicz
- Laboratory of Ageing Biology and Stem Cells, European Research Institute for the Biology of Ageing, University Medical Centre Groningen, University of Groningen, Antonius Deusinglaan 1, 9700 AV Groningen, the Netherlands
| | - Eric R Lechman
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada
| | - Karin G Hermans
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada
| | - Erwin M Schoof
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada
| | - Erno Wienholds
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada
| | - Ruth Isserlin
- The Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Peter A van Veelen
- Departments of Immunohematology and Blood Transfusion, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Mathilde J C Broekhuis
- Laboratory of Ageing Biology and Stem Cells, European Research Institute for the Biology of Ageing, University Medical Centre Groningen, University of Groningen, Antonius Deusinglaan 1, 9700 AV Groningen, the Netherlands
| | - George M C Janssen
- Departments of Immunohematology and Blood Transfusion, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Aaron Trotman-Grant
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada
| | - Stephanie M Dobson
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Gabriela Krivdova
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Jantje Elzinga
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada
| | - James Kennedy
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada
| | - Olga I Gan
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada
| | - Ankit Sinha
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada
| | - Vladimir Ignatchenko
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada
| | - Thomas Kislinger
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada
| | - Bertien Dethmers-Ausema
- Laboratory of Ageing Biology and Stem Cells, European Research Institute for the Biology of Ageing, University Medical Centre Groningen, University of Groningen, Antonius Deusinglaan 1, 9700 AV Groningen, the Netherlands
| | - Ellen Weersing
- Laboratory of Ageing Biology and Stem Cells, European Research Institute for the Biology of Ageing, University Medical Centre Groningen, University of Groningen, Antonius Deusinglaan 1, 9700 AV Groningen, the Netherlands
| | - Mir Farshid Alemdehy
- Department of Hematology, Erasmus University Medical Center Cancer Institute, Wytemaweg 80, 3015 CN Rotterdam, the Netherlands
| | - Hans W J de Looper
- Department of Hematology, Erasmus University Medical Center Cancer Institute, Wytemaweg 80, 3015 CN Rotterdam, the Netherlands
| | - Gary D Bader
- The Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Martha Ritsema
- Laboratory of Ageing Biology and Stem Cells, European Research Institute for the Biology of Ageing, University Medical Centre Groningen, University of Groningen, Antonius Deusinglaan 1, 9700 AV Groningen, the Netherlands
| | - Stefan J Erkeland
- Department of Immunology, Erasmus University Medical Center, Wytemaweg 80, 3015CN Rotterdam, the Netherlands
| | - Leonid V Bystrykh
- Laboratory of Ageing Biology and Stem Cells, European Research Institute for the Biology of Ageing, University Medical Centre Groningen, University of Groningen, Antonius Deusinglaan 1, 9700 AV Groningen, the Netherlands
| | - John E Dick
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.
| | - Gerald de Haan
- Laboratory of Ageing Biology and Stem Cells, European Research Institute for the Biology of Ageing, University Medical Centre Groningen, University of Groningen, Antonius Deusinglaan 1, 9700 AV Groningen, the Netherlands.
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Peng X, Giménez-Cassina A, Petrus P, Conrad M, Rydén M, Arnér ESJ. Thioredoxin reductase 1 suppresses adipocyte differentiation and insulin responsiveness. Sci Rep 2016; 6:28080. [PMID: 27346647 PMCID: PMC4921861 DOI: 10.1038/srep28080] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 05/31/2016] [Indexed: 12/21/2022] Open
Abstract
Recently thioredoxin reductase 1 (TrxR1), encoded by Txnrd1, was suggested to modulate glucose and lipid metabolism in mice. Here we discovered that TrxR1 suppresses insulin responsiveness, anabolic metabolism and adipocyte differentiation. Immortalized mouse embryonic fibroblasts (MEFs) lacking Txnrd1 (Txnrd1−/−) displayed increased metabolic flux, glycogen storage, lipogenesis and adipogenesis. This phenotype coincided with upregulated PPARγ expression, promotion of mitotic clonal expansion and downregulation of p27 and p53. Enhanced Akt activation also contributed to augmented adipogenesis and insulin sensitivity. Knockdown of TXNRD1 transcripts accelerated adipocyte differentiation also in human primary preadipocytes. Furthermore, TXNRD1 transcript levels in subcutaneous adipose tissue from 56 women were inversely associated with insulin sensitivity in vivo and lipogenesis in their isolated adipocytes. These results suggest that TrxR1 suppresses anabolic metabolism and adipogenesis by inhibition of intracellular signaling pathways downstream of insulin stimulation.
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Affiliation(s)
- Xiaoxiao Peng
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Alfredo Giménez-Cassina
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden.,Departamento de Biología Molecular, Universidad Autónoma de Madrid, Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), 28049, Madrid, Spain
| | - Paul Petrus
- Clinical Research Center, and the Department of Medicine, Huddinge University Hospital, Karolinska Institutet, SE-141 86 Stockholm, Sweden
| | - Marcus Conrad
- Helmholtz Zentrum München, Institute of Developmental Genetics, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Mikael Rydén
- Clinical Research Center, and the Department of Medicine, Huddinge University Hospital, Karolinska Institutet, SE-141 86 Stockholm, Sweden
| | - Elias S J Arnér
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
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Yan J, Xu J, Fei Y, Jiang C, Zhu W, Han Y, Lu S. TrxR2 deficiencies promote chondrogenic differentiation and induce apoptosis of chondrocytes through mitochondrial reactive oxygen species. Exp Cell Res 2016; 344:67-75. [DOI: 10.1016/j.yexcr.2016.04.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 04/14/2016] [Accepted: 04/19/2016] [Indexed: 01/09/2023]
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23
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Abu N, Yeap SK, Pauzi AZM, Akhtar MN, Zamberi NR, Ismail J, Zareen S, Alitheen NB. Dual Regulation of Cell Death and Cell Survival upon Induction of Cellular Stress by Isopimara-7,15-Dien-19-Oic Acid in Cervical Cancer, HeLa Cells In vitro. Front Pharmacol 2016; 7:89. [PMID: 27065873 PMCID: PMC4814465 DOI: 10.3389/fphar.2016.00089] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 03/18/2016] [Indexed: 11/14/2022] Open
Abstract
The Fritillaria imperialis is an ornamental flower that can be found in various parts of the world including Iraq, Afghanistan, Pakistan, and the Himalayas. The use of this plant as traditional remedy is widely known. This study aims to unveil the anti-cancer potentials of Isopimara-7,15-Dien-19-Oic Acid, extracted from the bulbs of F. imperialis in cervical cancer cell line, HeLa cells. Flow cytometry analysis of cell death, gene expression analysis via cDNA microarray and protein array were performed. Based on the results, Isopimara-7,15-Dien-19-Oic acid simultaneously induced cell death and promoted cell survival. The execution of apoptosis was apparent based on the flow cytometry results and regulation of both pro and anti-apoptotic genes. Additionally, the regulation of anti-oxidant genes were up-regulated especially thioredoxin, glutathione and superoxide dismutase- related genes. Moreover, the treatment also induced the activation of pro-survival heat shock proteins. Collectively, Isopimara-7,15-Dien-19-Oic Acid managed to induce cellular stress in HeLa cells and activate several anti- and pro survival pathways.
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Affiliation(s)
- Nadiah Abu
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia Serdang, Malaysia
| | - Swee K Yeap
- Laboratory of Immunotherapeutics and Vaccine (LIVES), Institute of Bioscience, Universiti Putra Malaysia Serdang, Malaysia
| | - Ahmad Z Mat Pauzi
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia Serdang, Malaysia
| | - M Nadeem Akhtar
- Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang Kuantan, Malaysia
| | - Nur R Zamberi
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia Serdang, Malaysia
| | - Jamil Ismail
- Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang Kuantan, Malaysia
| | - Seema Zareen
- Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang Kuantan, Malaysia
| | - Noorjahan B Alitheen
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia Serdang, Malaysia
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24
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Redel BK, Spate LD, Lee K, Mao J, Whitworth KM, Prather RS. Glycine supplementation in vitro enhances porcine preimplantation embryo cell number and decreases apoptosis but does not lead to live births. Mol Reprod Dev 2016; 83:246-58. [PMID: 26824641 PMCID: PMC5067679 DOI: 10.1002/mrd.22618] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 01/17/2016] [Indexed: 01/09/2023]
Abstract
Most in vitro culture conditions are less‐than‐optimal for embryo development. Here, we used a transcriptional‐profiling database to identify culture‐induced differences in gene expression in porcine blastocysts compared to in vivo‐produced counterparts. Genes involved in glycine transport (SLC6A9), glycine metabolism (GLDC, GCSH, DLD, and AMT), and serine metabolism (PSAT1, PSPH, and PHGDH) were differentially expressed. Addition of 10 mM glycine to the culture medium (currently containing 0.1 mM) reduced the abundance of SLC6A9 transcript and increased total cell number, primarily in the trophectoderm lineage (P = 0.003); this was likely by decreasing the percentage of apoptotic nuclei. As serine and glycine can be reversibly metabolized by serine hydroxymethyltransferase 2 (SHMT2), we assessed the abundance of SHMT2 transcript as well as its functional role by inhibiting it with aminomethylphosphonic acid (AMPA), a glycine analog, during in vitro culture. Both AMPA supplementation and elevated glycine decreased the mRNA abundance of SHMT2 and tumor protein p53 (TP53), which is activated in response to cellular stress, compared to controls (P ≤ 0.02). On the other hand, mitochondrial activity of blastocysts, mtDNA copy number, and abundance of mitochondria‐related transcripts did not differ between control and 10 mM glycine culture conditions. Despite improvements to these metrics of blastocyst quality, transfer of embryos cultured in 10 mM glycine did not result in pregnancy whereas the transfer of in vitro‐produced embryos cultured in control medium yielded live births. Mol. Reprod. Dev. 83: 246–258, 2016. © 2016 The Authors.
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Affiliation(s)
- Bethany K Redel
- Division of Animal Sciences, Animal Science Research Center, Columbia, Missouri
| | - Lee D Spate
- Division of Animal Sciences, Animal Science Research Center, Columbia, Missouri
| | - Kiho Lee
- Division of Animal Sciences, Animal Science Research Center, Columbia, Missouri
| | - Jiude Mao
- Division of Animal Sciences, Animal Science Research Center, Columbia, Missouri
| | - Kristin M Whitworth
- Division of Animal Sciences, Animal Science Research Center, Columbia, Missouri
| | - Randall S Prather
- Division of Animal Sciences, Animal Science Research Center, Columbia, Missouri
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Cebula M, Schmidt EE, Arnér ESJ. TrxR1 as a potent regulator of the Nrf2-Keap1 response system. Antioxid Redox Signal 2015; 23:823-53. [PMID: 26058897 PMCID: PMC4589110 DOI: 10.1089/ars.2015.6378] [Citation(s) in RCA: 184] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
SIGNIFICANCE All cells must maintain a balance between oxidants and reductants, while allowing for fluctuations in redox states triggered by signaling, altered metabolic flow, or extracellular stimuli. Furthermore, they must be able to rapidly sense and react to various challenges that would disrupt the redox homeostasis. RECENT ADVANCES Many studies have identified Keap1 as a key sensor for oxidative or electrophilic stress, with modification of Keap1 by oxidation or electrophiles triggering Nrf2-mediated transcriptional induction of enzymes supporting reductive and detoxification pathways. However, additional mechanisms for Nrf2 regulation are likely to exist upstream of, or in parallel with, Keap1. CRITICAL ISSUES Here, we propose that the mammalian selenoprotein thioredoxin reductase 1 (TrxR1) is a potent regulator of Nrf2. A high chemical reactivity of TrxR1 and its vital role for the thioredoxin (Trx) system distinguishes TrxR1 as a prime target for electrophilic challenges. Chemical modification of the selenocysteine (Sec) in TrxR1 by electrophiles leads to rapid inhibition of thioredoxin disulfide reductase activity, often combined with induction of NADPH oxidase activity of the derivatized enzyme, thereby affecting many downstream redox pathways. The notion of TrxR1 as a regulator of Nrf2 is supported by many publications on effects in human cells of selenium deficiency, oxidative stress or electrophile exposure, as well as the phenotypes of genetic mouse models. FUTURE DIRECTIONS Investigation of the role of TrxR1 as a regulator of Nrf2 activation will facilitate further studies of redox control in diverse cells and tissues of mammals, and possibly also in animals of other classes.
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Affiliation(s)
- Marcus Cebula
- 1 Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet , Stockholm, Sweden
| | - Edward E Schmidt
- 2 Microbiology and Immunology, Montana State University , Bozeman, Montana
| | - Elias S J Arnér
- 1 Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet , Stockholm, Sweden
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