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Potential Cytoprotective and Regulatory Effects of Ergothioneine on Gene Expression of Proteins Involved in Erythroid Adaptation Mechanisms and Redox Pathways in K562 Cells. Genes (Basel) 2022; 13:genes13122368. [PMID: 36553634 PMCID: PMC9778224 DOI: 10.3390/genes13122368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 12/08/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
This study aimed to establish the importance of ergothioneine (ERT) in the erythroid adaptation mechanisms by appraising the expression levels of redox-related genes associated with the PI3K/AKT/FoxO3 and Nrf2-ARE pathways using K562 cells induced to erythroid differentiation and H2O2-oxidative stress. Cell viability and gene expression were evaluated. Two concentrations of ERT were assessed, 1 nM (C1) and 100 µM (C2), with and without stress induction (100 µM H2O2). Assessments were made in three periods of the cellular differentiation process (D0, D2, and D4). The C1 treatment promoted the induction of FOXO3 (D0 and 2), PSMB5, and 6 expressions (D4); C1 + H2O2 treatment showed the highest levels of NRF2 transcripts, KEAP1 (D0), YWHAQ (D2 and 4), PSMB5 (D2) and PSMB6 (D4); and C2 + H2O2 (D2) an increase in FOXO3 and MST1 expression, with a decrease of YWHAQ and NRF2 was observed. in C2 + H2O2 (D2) an increase in FOXO3 and MST1, with a decrease in YWHAQ and NRF2 was observed All ERT treatments increased gamma-globin expression. Statistical multivariate analyzes highlighted that the Nrf2-ARE pathway presented a greater contribution in the production of PRDX1, SOD1, CAT, and PSBM5 mRNAs, whereas the PI3K/AKT/FoxO3 pathway was associated with the PRDX2 and TRX transcripts. In conclusion, ERT presented a cytoprotective action through Nrf2 and FoxO3, with the latter seeming to contribute to erythroid proliferation/differentiation.
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Protective Effect of Ergothioneine Against Stroke in Rodent Models. Neuromolecular Med 2022:10.1007/s12017-022-08727-w. [PMID: 36261765 DOI: 10.1007/s12017-022-08727-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 10/09/2022] [Indexed: 10/24/2022]
Abstract
Ergothioneine (ET) is a naturally occurring antioxidant and cytoprotective agent that is synthesized by fungi and certain bacteria. Recent studies have shown a beneficial effect of ET on neurological functions, including cognition and animal models of depression. The aim of this study is to elucidate a possible effect of ET in rodent models of stroke. Post-ischemic intracerebroventricular (i.c.v.) infusion of ET significantly reduced brain infarct volume by as early as 1 day after infusion in rats, as shown by triphenyltetrazolium chloride (TTC) assay. There was a dose-dependent increase in protection, from 50 to 200 ng of ET infusion. These results suggest that ET could have a protective effect on CNS neurons. We next elucidated the effect of systemic ET on brain infarct volume in mice after stroke. Daily i.p. injection of 35 mg/kg ET (the first dose being administered 3 h after stroke) had no significant effect on infarct volume. However, daily i.p. injections of 70 mg/kg, 100 mg/kg, 125 mg/kg and 150 mg/kg ET, with the first dose administered 3 h after stroke, significantly decreased infarct volume at 7 days after vessel occlusion in mice. In order to elucidate at what time interval during the 7 days there could be effective protection, a second set of experiments was carried out in mice, using one of the effective loading protocols, i.e. 125 mg/kg i.p. ET but the brains were analyzed at 1, 4 and 7 days post-stroke by MRI. We found that ET was already protective against neuronal injury and decreased the size of the brain infarct from as early as 1 day post-stroke. Behavioral experiments carried out on a third set of mice (using 125 mg/kg i.p. ET) showed that this was accompanied by significant improvements in certain behaviors (pole test) at 1 day after stroke. Together, results of this study indicate that i.c.v. and systemic ET are effective in reducing brain infarct volume after stroke in rodent models.
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Shang H, Sun Y, Wang Z, Zhou Y, Yang H, Ci X, Cui T, Xia Y, Gu Y, Liao M, Li Q, Si D, Liu C. Intestinal absorption mechanism of rotundic acid: Involvement of P-gp and OATP2B1. JOURNAL OF ETHNOPHARMACOLOGY 2022; 289:115006. [PMID: 35051604 DOI: 10.1016/j.jep.2022.115006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 01/13/2022] [Accepted: 01/15/2022] [Indexed: 06/14/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Ilicis Rotundae Cortex (IRC), the dried barks of Ilex rotunda Thunb. (Aquifoliaceae), has been used for the prevention or treatment of colds, tonsillitis, dysentery, and gastrointestinal diseases in folk medicine due to its antibacterial and anti-inflammatory effects. However, there is no report about the intestinal absorption of major compounds that support traditional usage. AIM OF STUDY Considering the potential of rotundic acid (RA) - major biologically active pentacyclic triterpenes found in the IRC, this study was purposed to uncover the oral absorption mechanism of RA using in situ single-pass intestinal perfusion (SPIP) model, in vitro cell models (Caco-2, MDCKII-WT, MDCKII-MDR1, MDCKII-BCRP, and HEK293-OATP2B1 cells) and in vivo pharmacokinetics studies in rats. MATERIALS AND METHODS The molecular properties (solubility, lipophilicity, and chemical stability) and the effects of principal parameters (time, compound concentrations, pH, paracellular pathway, and the different intestinal segments) were analyzed by liquid chromatography-tandem mass spectrometry. The susceptibility of RA to various inhibitors, such as P-gp inhibitor verapamil, BCRP inhibitor Ko143, OATP 2B1 inhibitor rifampicin, and absorption enhancer EGTA were assessed. RESULTS RA was a compound with low water solubility (12.89 μg/mL) and strong lipophilicity (LogP = 4.1). RA was considered stable in all media during the SPIP and transport studies. The SPIP and cell experiments showed RA was moderate absorbed in the intestines and exhibited time, concentration, pH, and segment-dependent permeability. In addition, results from the cell model, in situ SPIP model as well as the in vivo pharmacokinetics studies consistently showed that verapamil, rifampicin, and EGTA might have significant effect on the intestinal absorption of RA. CONCLUSION The mechanisms of intestinal absorption of RA might involve multiple transport pathways, including passive diffusion, the participation of efflux (i.e., P-gp) and influx (i.e., OATP2B1) transporters, and paracellular pathways.
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Affiliation(s)
- Haihua Shang
- State Key Laboratory of Drug Delivery and Pharmacokinetics, Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China; Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine, Peking Union Medical College & Chinese Academy of Medical Sciences, Tianjin, 300192, China
| | - Yinghui Sun
- Research Center of Bio-Technology, Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China
| | - Ze Wang
- College of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China
| | - Ying Zhou
- State Key Laboratory of Drug Delivery and Pharmacokinetics, Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China
| | - Huajiao Yang
- State Key Laboratory of Drug Delivery and Pharmacokinetics, Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China
| | - Xiaoyan Ci
- Research Center of Bio-Technology, Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China
| | - Tao Cui
- Research Center of Bio-Technology, Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China
| | - Yuanyuan Xia
- Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China; Research Unit for Drug Metabolism, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Yuan Gu
- Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China; Research Unit for Drug Metabolism, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Maoliang Liao
- State Key Laboratory of Drug Delivery and Pharmacokinetics, Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China; Tianjin Ringpu Bio-technology Co., Ltd., Tianjin, 300308, China.
| | - Quansheng Li
- State Key Laboratory of Drug Delivery and Pharmacokinetics, Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China
| | - Duanyun Si
- State Key Laboratory of Drug Delivery and Pharmacokinetics, Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China; Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China; Research Unit for Drug Metabolism, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Changxiao Liu
- State Key Laboratory of Drug Delivery and Pharmacokinetics, Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China; Tianjin Institute of Pharmaceutical Research, Tianjin, 300000, China; Research Unit for Drug Metabolism, Chinese Academy of Medical Sciences, Beijing, 100730, China.
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Müller JP, Gründemann D. Does Intracellular Metabolism Render Gemcitabine Uptake Undetectable in Mass Spectrometry? Int J Mol Sci 2022; 23:ijms23094690. [PMID: 35563081 PMCID: PMC9101085 DOI: 10.3390/ijms23094690] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 04/19/2022] [Accepted: 04/22/2022] [Indexed: 02/06/2023] Open
Abstract
The ergothioneine transporter ETT (formerly OCTN1; human gene symbol SLC22A4) is a powerful and highly specific transporter for the uptake of ergothioneine (ET). Recently, Sparreboom et al. reported that the ETT would transport nucleosides and nucleoside analogues such as cytarabine and gemcitabine with the highest efficiency. In our assay system, we could not detect any such transport. Subsequently, Sparreboom suggested that the intracellular metabolization of the nucleosides occurs so fast that the original compounds cannot be detected by LC–MS/MS after inward transport. Our current experiments with 293 cells disprove this hypothesis. Uptake of gemcitabine was easily detected by LC–MS/MS measurements when we expressed the Na+/nucleoside cotransporter CNT3 (SLC28A3). Inward transport was 1280 times faster than the intracellular production of gemcitabine triphosphate. The deoxycytidine kinase inhibitor 2-thio-2′-deoxycytidine markedly blocked the production of gemcitabine triphosphate. There was no concomitant surge in intracellular gemcitabine, however. This does not fit the rapid phosphorylation of gemcitabine. Uptake of cytarabine was very slow, but detection by MS was still possible. When the ETT was expressed and incubated with gemcitabine, there was no increase in intracellular gemcitabine triphosphate. We conclude that the ETT does not transport nucleosides.
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Oxidized Forms of Ergothioneine Are Substrates for Mammalian Thioredoxin Reductase. Antioxidants (Basel) 2022; 11:antiox11020185. [PMID: 35204068 PMCID: PMC8868364 DOI: 10.3390/antiox11020185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/16/2022] [Accepted: 01/17/2022] [Indexed: 11/17/2022] Open
Abstract
Ergothioneine (EGT) is a sulfur-containing amino acid analog that is biosynthesized in fungi and bacteria, accumulated in plants, and ingested by humans where it is concentrated in tissues under oxidative stress. While the physiological function of EGT is not yet fully understood, EGT is a potent antioxidant in vitro. Here we report that oxidized forms of EGT, EGT-disulfide (ESSE) and 5-oxo-EGT, can be reduced by the selenoenzyme mammalian thioredoxin reductase (Sec-TrxR). ESSE and 5-oxo-EGT are formed upon reaction with biologically relevant reactive oxygen species. We found that glutathione reductase (GR) can reduce ESSE, but only with the aid of glutathione (GSH). The reduction of ESSE by TrxR was found to be selenium dependent, with non-selenium-containing TrxR enzymes having little or no ability to reduce ESSE. In comparing the reduction of ESSE by Sec-TrxR in the presence of thioredoxin to that of GR/GSH, we find that the glutathione system is 10-fold more efficient, but Sec-TrxR has the advantage of being able to reduce both ESSE and 5-oxo-EGT directly. This represents the first discovered direct enzymatic recycling system for oxidized forms of EGT. Based on our in vitro results, the thioredoxin system may be important for EGT redox biology and requires further in vivo investigation.
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Gründemann D, Hartmann L, Flögel S. The Ergothioneine Transporter (ETT): Substrates and Locations, an Inventory. FEBS Lett 2021; 596:1252-1269. [PMID: 34958679 DOI: 10.1002/1873-3468.14269] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/21/2021] [Accepted: 12/22/2021] [Indexed: 11/07/2022]
Abstract
In all vertebrates including mammals, the ergothioneine transporter ETT (obsolete name OCTN1; human gene symbol SLC22A4) is a powerful and highly specific transporter for the uptake of ergothioneine (ET). ETT is not expressed ubiquitously and only cells with high ETT cell-surface levels can accumulate ET to high concentration. Without ETT, there is no uptake because the plasma membrane is essentially impermeable to this hydrophilic zwitterion. Here, we review the substrate specificity and localization of ETT, which is prominently expressed in neutrophils, monocytes/macrophages, and developing erythrocytes. Most sites of strong expression are conserved across species, but there are also major differences. In particular, we critically analyze the evidence for the expression of ETT in the brain as well as recent data suggesting that the transporter SLC22A15 may transport also ET. We conclude that, to date, ETT remains the only well-defined biomarker for intracellular ET activity. In humans, the ability to take up, distribute, and retain ET depends principally on this transporter.
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Affiliation(s)
- Dirk Gründemann
- Department of Pharmacology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Gleueler Straße 24, 50931, Cologne, Germany
| | - Lea Hartmann
- Department of Pharmacology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Gleueler Straße 24, 50931, Cologne, Germany
| | - Svenja Flögel
- Department of Pharmacology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Gleueler Straße 24, 50931, Cologne, Germany
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López de Heredia M, Muñoz L, Carru C, Sotgia S, Zinellu A, Serra C, Llebaria A, Kato Y, Nunes V. S-Methyl-L-Ergothioneine to L-Ergothioneine Ratio in Urine Is a Marker of Cystine Lithiasis in a Cystinuria Mouse Model. Antioxidants (Basel) 2021; 10:antiox10091424. [PMID: 34573056 PMCID: PMC8471778 DOI: 10.3390/antiox10091424] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 08/30/2021] [Accepted: 08/31/2021] [Indexed: 11/30/2022] Open
Abstract
Cystinuria, a rare inherited aminoaciduria condition, is characterized by the hyperexcretion of cystine, ornithine, lysine, and arginine. Its main clinical manifestation is cystine stone formation in the urinary tract, being responsible for 1–2% total and 6–8% pediatric lithiasis. Cystinuria patients suffer from recurrent lithiasic episodes that might end in surgical interventions, progressive renal functional deterioration, and kidney loss. Cystinuria is monitored for the presence of urinary cystine stones by crystalluria, imaging techniques or urinary cystine capacity; all with limited predicting capabilities. We analyzed blood and urine levels of the natural antioxidant L-ergothioneine in a Type B cystinuria mouse model, and urine levels of its metabolic product S-methyl-L-ergothioneine, in both male and female mice at two different ages and with different lithiasic phenotype. Urinary levels of S-methyl-L-ergothioneine showed differences related to age, gender and lithiasic phenotype. Once normalized by L-ergothioneine to account for interindividual differences, the S-methyl-L-ergothioneine to L-ergothioneine urinary ratio discriminated between cystine lithiasic phenotypes. Urine S-methyl-L-ergothioneine to L-ergothioneine ratio could be easily determined in urine and, as being capable of discriminating between cystine lithiasis phenotypes, it could be used as a lithiasis biomarker in cystinuria patient management.
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Affiliation(s)
- Miguel López de Heredia
- Human Molecular Genetics Laboratory, Gene, Disease and Therapy Program, IDIBELL, L’Hospitalet de Llobregat, 08908 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER)-CB06/07/0069, Instituto de Salud Carlos III, 28029 Madrid, Spain
- Correspondence: (M.L.d.H.); (V.N.); Tel.: +34-93-260-4706 (M.L.d.H. & V.N.)
| | - Lourdes Muñoz
- SIMChem, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), 08034 Barcelona, Spain; (L.M.); (C.S.); (A.L.)
| | - Ciriaco Carru
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (C.C.); (S.S.); (A.Z.)
| | - Salvatore Sotgia
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (C.C.); (S.S.); (A.Z.)
| | - Angelo Zinellu
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (C.C.); (S.S.); (A.Z.)
| | - Carmen Serra
- SIMChem, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), 08034 Barcelona, Spain; (L.M.); (C.S.); (A.L.)
| | - Amadeu Llebaria
- SIMChem, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), 08034 Barcelona, Spain; (L.M.); (C.S.); (A.L.)
- MCS, Laboratory of Medicinal Chemistry, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), 08034 Barcelona, Spain
| | - Yukio Kato
- Faculty of Pharmacy, Kanazawa University, Kanazawa 920-1192, Japan;
| | - Virginia Nunes
- Human Molecular Genetics Laboratory, Gene, Disease and Therapy Program, IDIBELL, L’Hospitalet de Llobregat, 08908 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER)-CB06/07/0069, Instituto de Salud Carlos III, 28029 Madrid, Spain
- Genetics Section, Physiological Sciences Department, Health Sciences and Medicine Faculty, University of Barcelona, 08907 Barcelona, Spain
- Correspondence: (M.L.d.H.); (V.N.); Tel.: +34-93-260-4706 (M.L.d.H. & V.N.)
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Lam-Sidun D, Peters KM, Borradaile NM. Mushroom-Derived Medicine? Preclinical Studies Suggest Potential Benefits of Ergothioneine for Cardiometabolic Health. Int J Mol Sci 2021; 22:ijms22063246. [PMID: 33806754 PMCID: PMC8004618 DOI: 10.3390/ijms22063246] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/17/2021] [Accepted: 03/19/2021] [Indexed: 12/18/2022] Open
Abstract
Medicinal use of mushrooms has been documented since ancient times, and in the modern world, mushrooms have a longstanding history of use in Eastern medicine. Recent interest in plant-based diets in Westernized countries has brought increasing attention to the use of mushrooms and mushroom-derived compounds in the prevention and treatment of chronic diseases. Edible mushrooms are the most abundant food sources of the modified amino acid, ergothioneine. This compound has been shown to accumulate in almost all cells and tissues, but preferentially in those exposed to oxidative stress and injury. The demonstrated cytoprotectant effect of ergothioneine has led many to suggest a potential therapeutic role for this compound in chronic conditions that involve ongoing oxidative stress and inflammation, including cardiovascular and metabolic diseases. However, the in vivo effects of ergothioneine and its underlying therapeutic mechanisms in the whole organism are not as clear. Moreover, there are no well-defined, clinical prevention and intervention trials of ergothioneine in chronic disease. This review highlights the cellular and molecular mechanisms of action of ergothioneine and its potential as a Traditional, Complementary and Alternative Medicine for the promotion of cardiometabolic health and the management of the most common manifestations of cardiometabolic disease.
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Transporter tandems: precise tools for normalizing active transporter in the plasma membrane. Biochem J 2021; 477:4191-4206. [PMID: 33073844 DOI: 10.1042/bcj20200666] [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: 08/20/2020] [Revised: 10/12/2020] [Accepted: 10/19/2020] [Indexed: 12/12/2022]
Abstract
The transport efficiency (TE) describes the performance of a transport protein for a specific substrate. To compare the TE of different transporters, the number of active transporters in the plasma membrane must be monitored, as it may vary for each transporter and experiment. Available methods, like LC-MS quantification of tryptic peptides, fail to discriminate inactive intracellular transporters or, like cell-surface biotinylation followed by affinity chromatography and Western blotting, are imprecise and very laborious. We wanted to normalize active transporters by the activity of a second transporter. A transporter tandem, generated by joining two transporter cDNAs into a single open reading frame, should guarantee a 1 : 1 stoichiometry. Here we created a series of tandems with different linkers between the human ergothioneine (ET) transporter ETT (gene symbol SLC22A4) and organic cation transporter OCT2 (SLC22A2). The linker sequence strongly affected the expression strength. The stoichiometry was validated by absolute peptide quantification and untargeted peptide analysis. Compared with wild-type ETT, the normalized ET clearance of the natural variant L503F was higher (f = 1.34); G462E was completely inactive. The general usefulness of the tandem strategy was demonstrated by linking several transporters with ETT; every construct was active in both parts. Transporter tandems can be used - without membrane isolation or protein quantification - as precise tools for transporter number normalization, to identify, for example, relevant transporters for a drug. It is necessary, however, to find suitable linkers, to check the order of transporters, and to verify the absence of functional interference by saturation kinetics.
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Borodina I, Kenny LC, McCarthy CM, Paramasivan K, Pretorius E, Roberts TJ, van der Hoek SA, Kell DB. The biology of ergothioneine, an antioxidant nutraceutical. Nutr Res Rev 2020; 33:190-217. [PMID: 32051057 PMCID: PMC7653990 DOI: 10.1017/s0954422419000301] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 11/20/2019] [Accepted: 11/25/2019] [Indexed: 02/07/2023]
Abstract
Ergothioneine (ERG) is an unusual thio-histidine betaine amino acid that has potent antioxidant activities. It is synthesised by a variety of microbes, especially fungi (including in mushroom fruiting bodies) and actinobacteria, but is not synthesised by plants and animals who acquire it via the soil and their diet, respectively. Animals have evolved a highly selective transporter for it, known as solute carrier family 22, member 4 (SLC22A4) in humans, signifying its importance, and ERG may even have the status of a vitamin. ERG accumulates differentially in various tissues, according to their expression of SLC22A4, favouring those such as erythrocytes that may be subject to oxidative stress. Mushroom or ERG consumption seems to provide significant prevention against oxidative stress in a large variety of systems. ERG seems to have strong cytoprotective status, and its concentration is lowered in a number of chronic inflammatory diseases. It has been passed as safe by regulatory agencies, and may have value as a nutraceutical and antioxidant more generally.
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Affiliation(s)
- Irina Borodina
- The Novo Nordisk Foundation Center for Biosustainability, Building 220, Chemitorvet 200, Technical University of Denmark, 2800Kongens Lyngby, Denmark
| | - Louise C. Kenny
- Department of Women’s and Children’s Health, Institute of Translational Medicine, University of Liverpool, Crown Street, LiverpoolL8 7SS, UK
| | - Cathal M. McCarthy
- Irish Centre for Fetal and Neonatal Translational Research (INFANT), Cork University Maternity Hospital, Cork, Republic of Ireland
- Department of Pharmacology and Therapeutics, Western Gateway Building, University College Cork, Cork, Republic of Ireland
| | - Kalaivani Paramasivan
- The Novo Nordisk Foundation Center for Biosustainability, Building 220, Chemitorvet 200, Technical University of Denmark, 2800Kongens Lyngby, Denmark
| | - Etheresia Pretorius
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, Private Bag X1 Matieland, 7602, South Africa
| | - Timothy J. Roberts
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, Private Bag X1 Matieland, 7602, South Africa
- Department of Biochemistry, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Crown Street, LiverpoolL69 7ZB, UK
| | - Steven A. van der Hoek
- The Novo Nordisk Foundation Center for Biosustainability, Building 220, Chemitorvet 200, Technical University of Denmark, 2800Kongens Lyngby, Denmark
| | - Douglas B. Kell
- The Novo Nordisk Foundation Center for Biosustainability, Building 220, Chemitorvet 200, Technical University of Denmark, 2800Kongens Lyngby, Denmark
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, Private Bag X1 Matieland, 7602, South Africa
- Department of Biochemistry, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Crown Street, LiverpoolL69 7ZB, UK
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Organic Cation Transporters in the Lung-Current and Emerging (Patho)Physiological and Pharmacological Concepts. Int J Mol Sci 2020; 21:ijms21239168. [PMID: 33271927 PMCID: PMC7730617 DOI: 10.3390/ijms21239168] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/24/2020] [Accepted: 11/27/2020] [Indexed: 02/07/2023] Open
Abstract
Organic cation transporters (OCT) 1, 2 and 3 and novel organic cation transporters (OCTN) 1 and 2 of the solute carrier 22 (SLC22) family are involved in the cellular transport of endogenous compounds such as neurotransmitters, l-carnitine and ergothioneine. OCT/Ns have also been implicated in the transport of xenobiotics across various biological barriers, for example biguanides and histamine receptor antagonists. In addition, several drugs used in the treatment of respiratory disorders are cations at physiological pH and potential substrates of OCT/Ns. OCT/Ns may also be associated with the development of chronic lung diseases such as allergic asthma and chronic obstructive pulmonary disease (COPD) and, thus, are possible new drug targets. As part of the Special Issue "Physiology, Biochemistry and Pharmacology of Transporters for Organic Cations", this review provides an overview of recent findings on the (patho)physiological and pharmacological functions of organic cation transporters in the lung.
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Yee SW, Buitrago D, Stecula A, Ngo HX, Chien HC, Zou L, Koleske ML, Giacomini KM. Deorphaning a solute carrier 22 family member, SLC22A15, through functional genomic studies. FASEB J 2020; 34:15734-15752. [PMID: 33124720 DOI: 10.1096/fj.202001497r] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 08/10/2020] [Accepted: 08/19/2020] [Indexed: 12/12/2022]
Abstract
The human solute carrier 22A (SLC22A) family consists of 23 members, representing one of the largest families in the human SLC superfamily. Despite their pharmacological and physiological importance in the absorption and disposition of a range of solutes, eight SLC22A family members remain classified as orphans. In this study, we used a multifaceted approach to identify ligands of orphan SLC22A15. Ligands of SLC22A15 were proposed based on phylogenetic analysis and comparative modeling. The putative ligands were then confirmed by metabolomic screening and uptake assays in SLC22A15 transfected HEK293 cells. Metabolomic studies and transporter assays revealed that SLC22A15 prefers zwitterionic compounds over cations and anions. We identified eight zwitterions, including ergothioneine, carnitine, carnosine, gabapentin, as well as four cations, including MPP+ , thiamine, and cimetidine, as substrates of SLC22A15. Carnosine was a specific substrate of SLC22A15 among the transporters in the SLC22A family. SLC22A15 transport of several substrates was sodium-dependent and exhibited a higher Km for ergothioneine, carnitine, and carnosine compared to previously identified transporters for these ligands. This is the first study to characterize the function of SLC22A15. Our studies demonstrate that SLC22A15 may play an important role in determining the systemic and tissue levels of ergothioneine, carnosine, and other zwitterions.
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Affiliation(s)
- Sook Wah Yee
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Dina Buitrago
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Adrian Stecula
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Huy X Ngo
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Huan-Chieh Chien
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Ling Zou
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Megan L Koleske
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Kathleen M Giacomini
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA.,Institute for Human Genetics, University of California San Francisco, San Francisco, CA, USA
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13
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Effect of Ergothioneine on 7-Ketocholesterol-Induced Endothelial Injury. Neuromolecular Med 2020; 23:184-198. [PMID: 33067719 PMCID: PMC7567423 DOI: 10.1007/s12017-020-08620-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 10/06/2020] [Indexed: 12/21/2022]
Abstract
Ergothioneine (ET) is a naturally occurring antioxidant that is synthesized by non-yeast fungi and certain bacteria. ET is not synthesized by animals, including humans, but is avidly taken up from the diet, especially from mushrooms. In the current study, we elucidated the effect of ET on the hCMEC/D3 human brain endothelial cell line. Endothelial cells are exposed to high levels of the cholesterol oxidation product, 7-ketocholesterol (7KC), in patients with cardiovascular disease and diabetes, and this process is thought to mediate pathological inflammation. 7KC induces a dose-dependent loss of cell viability and an increase in apoptosis and necrosis in the endothelial cells. A relocalization of the tight junction proteins, zonula occludens-1 (ZO-1) and claudin-5, towards the nucleus of the cells was also observed. These effects were significantly attenuated by ET. In addition, 7KC induces marked increases in the mRNA expression of pro-inflammatory cytokines, IL-1β IL-6, IL-8, TNF-α and cyclooxygenase-2 (COX2), as well as COX2 enzymatic activity, and these were significantly reduced by ET. Moreover, the cytoprotective and anti-inflammatory effects of ET were significantly reduced by co-incubation with an inhibitor of the ET transporter, OCTN1 (VHCL). This shows that ET needs to enter the endothelial cells to have a protective effect and is unlikely to act via extracellular neutralizing of 7KC. The protective effect on inflammation in brain endothelial cells suggests that ET might be useful as a nutraceutical for the prevention or management of neurovascular diseases, such as stroke and vascular dementia. Moreover, the ability of ET to cross the blood-brain barrier could point to its usefulness in combatting 7KC that is produced in the CNS during neuroinflammation, e.g. after excitotoxicity, in chronic neurodegenerative diseases, and possibly COVID-19-related neurologic complications.
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14
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Hosain MZ, Hyodo F, Mori T, Takahashi K, Nagao Y, Eto H, Murata M, Akahoshi T, Matsuo M, Katayama Y. Development of a novel molecular probe for the detection of liver mitochondrial redox metabolism. Sci Rep 2020; 10:16489. [PMID: 33020535 PMCID: PMC7536409 DOI: 10.1038/s41598-020-73336-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 09/15/2020] [Indexed: 11/10/2022] Open
Abstract
Redox status influences the course of the inflammatory, metabolic, and proliferative liver diseases. Oxidative stress is thought to play a crucial and sustained role in the pathological progression of early steatosis to severe hepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. Oxidative stress induced by reactive oxygen species which are generated in the mitochondria can lead to chronic organelle damage in hepatocytes. Currently, the diagnosis of liver disease requires liver biopsy, which is invasive and associated with complications. The present report describes the development of a novel molecular probe, EDA-PROXYL, with higher reactivity and mitochondrial selectivity than standard carboxyl-PROXYL and carbamoyl-PROXYL probes. The membrane permeability of our probe improved in aqueous environments which led to increased accumulation in the liver and interaction of EDA-PROXYL with the carnitine transporter via the amine (NH3+) group further increased accumulation. This increased mitochondrial sensitivity and enhanced accumulation highlight the potential of EDA-PROXYL as a molecular probe for determining metabolic reactions of the mitochondria. Thus, this novel probe could be a tool for the evaluation of redox status of the mitochondria to assess the degree of liver injury and, ultimately, the response to pharmacological therapy.
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Affiliation(s)
- Md Zahangir Hosain
- Graduate School of Systems Life Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Fuminori Hyodo
- Department of Radiology, School of Medicine, Gifu University, 1-1 Yanagido, Gifu, 501-1194, Japan.
- Innovation Center for Medical Redox Navigation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
- Department of Frontier Science for Imaging, School of Medicine, Gifu University, 1-1 Yanagido, Gifu, 501-1194, Japan.
| | - Takeshi Mori
- Graduate School of Systems Life Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.
- Department of Applied Chemistry, Faculty of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.
- Center for Future Chemistry, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.
| | - Koyo Takahashi
- Graduate School of Systems Life Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Yusuke Nagao
- Graduate School of Systems Life Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Hinako Eto
- Innovation Center for Medical Redox Navigation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
- Center for Advanced Medical Innovation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Masaharu Murata
- Innovation Center for Medical Redox Navigation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
- Center for Advanced Medical Innovation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Tomohiko Akahoshi
- Center for Advanced Medical Innovation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Masayuki Matsuo
- Department of Radiology, School of Medicine, Gifu University, 1-1 Yanagido, Gifu, 501-1194, Japan
| | - Yoshiki Katayama
- Graduate School of Systems Life Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
- Department of Applied Chemistry, Faculty of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
- Center for Future Chemistry, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
- International Research Center for Molecular Systems, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
- Center for Advanced Medical Innovation, Kyushu University, 744 Motooka, Nishi-Ku, Fukuoka, 819-0395, Japan
- Department of Biomedical Engineering, Chung Yuan Christian University, 200 Chung Pei Rd., Chung Li, 32023, Taiwan, ROC
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15
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Abstract
The organic cation transporters (OCTs) OCT1, OCT2, OCT3, novel OCT (OCTN)1, OCTN2, multidrug and toxin exclusion (MATE)1, and MATE kidney-specific 2 are polyspecific transporters exhibiting broadly overlapping substrate selectivities. They transport organic cations, zwitterions, and some uncharged compounds and operate as facilitated diffusion systems and/or antiporters. OCTs are critically involved in intestinal absorption, hepatic uptake, and renal excretion of hydrophilic drugs. They modulate the distribution of endogenous compounds such as thiamine, L-carnitine, and neurotransmitters. Sites of expression and functions of OCTs have important impact on energy metabolism, pharmacokinetics, and toxicity of drugs, and on drug-drug interactions. In this work, an overview about the human OCTs is presented. Functional properties of human OCTs, including identified substrates and inhibitors of the individual transporters, are described. Sites of expression are compiled, and data on regulation of OCTs are presented. In addition, genetic variations of OCTs are listed, and data on their impact on transport, drug treatment, and diseases are reported. Moreover, recent data are summarized that indicate complex drug-drug interaction at OCTs, such as allosteric high-affinity inhibition of transport and substrate dependence of inhibitor efficacies. A hypothesis about the molecular mechanism of polyspecific substrate recognition by OCTs is presented that is based on functional studies and mutagenesis experiments in OCT1 and OCT2. This hypothesis provides a framework to imagine how observed complex drug-drug interactions at OCTs arise. Finally, preclinical in vitro tests that are performed by pharmaceutical companies to identify interaction of novel drugs with OCTs are discussed. Optimized experimental procedures are proposed that allow a gapless detection of inhibitory and transported drugs.
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Affiliation(s)
- Hermann Koepsell
- Institute of Anatomy and Cell Biology and Department of Molecular Plant Physiology and Biophysics, Julius-von-Sachs-Institute, University of Würzburg, Würzburg, Germany
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16
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Song H, Naowarojna N, Cheng R, Lopez J, Liu P. Non-heme iron enzyme-catalyzed complex transformations: Endoperoxidation, cyclopropanation, orthoester, oxidative C-C and C-S bond formation reactions in natural product biosynthesis. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2019; 117:1-61. [PMID: 31564305 DOI: 10.1016/bs.apcsb.2019.06.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Non-heme iron enzymes catalyze a wide range of chemical transformations, serving as one of the key types of tailoring enzymes in the biosynthesis of natural products. Hydroxylation reaction is the most common type of reactions catalyzed by these enzymes and hydroxylation reactions have been extensively investigated mechanistically. However, the mechanistic details for other types of transformations remain largely unknown or unexplored. In this paper, we present some of the most recently discovered transformations, including endoperoxidation, orthoester formation, cyclopropanation, oxidative C-C and C-S bond formation reactions. In addition, many of them are multi-functional enzymes, which further complicate their mechanistic investigations. In this work, we summarize their biosynthetic pathways, with special emphasis on the mechanistic details available for these newly discovered enzymes.
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Affiliation(s)
- Heng Song
- College of Chemistry and Molecular Sciences, Wuhan University, Hubei, People's Republic of China
| | | | - Ronghai Cheng
- Department of Chemistry, Boston University, Boston, MA, United States
| | - Juan Lopez
- Department of Chemistry, Boston University, Boston, MA, United States
| | - Pinghua Liu
- Department of Chemistry, Boston University, Boston, MA, United States
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17
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The role of low molecular weight thiols in Mycobacterium tuberculosis. Tuberculosis (Edinb) 2019; 116:44-55. [PMID: 31153518 DOI: 10.1016/j.tube.2019.04.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 04/16/2019] [Accepted: 04/22/2019] [Indexed: 02/06/2023]
Abstract
Low molecular weight (LMW) thiols are molecules with a functional sulfhydryl group that enable them to detoxify reactive oxygen species, reactive nitrogen species and other free radicals. Their roles range from their ability to modulate the immune system to their ability to prevent damage of biological molecules such as DNA and proteins by protecting against oxidative, nitrosative and acidic stress. LMW thiols are synthesized and found in both eukaryotes and prokaryotes. Due to their beneficial role to both eukaryotes and prokaryotes, their specific functions need to be elucidated, most especially in pathogenic prokaryotes such as Mycobacterium tuberculosis (M.tb), in order to provide a rationale for targeting their biosynthesis for drug development. Ergothioneine (ERG), mycothiol (MSH) and gamma-glutamylcysteine (GGC) are LMW thiols that have been shown to interplay to protect M.tb against cellular stress. Though ERG, MSH and GGC seem to have overlapping functions, studies are gradually revealing their unique physiological roles. Understanding their unique physiological role during the course of tuberculosis (TB) infection, would pave the way for the development of drugs that target their biosynthetic pathway. This review identifies the knowledge gap in the unique physiological roles of LMW thiols and proposes their mechanistic roles based on previous studies. In addition, it gives an update on identified inhibitors of their biosynthetic enzymes.
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18
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Oumari M, Goldfuss B, Stoffels C, Schmalz HG, Gründemann D. Regeneration of ergothioneine after reaction with singlet oxygen. Free Radic Biol Med 2019; 134:498-504. [PMID: 30721726 DOI: 10.1016/j.freeradbiomed.2019.01.043] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 01/24/2019] [Accepted: 01/30/2019] [Indexed: 01/09/2023]
Abstract
Ergothioneine (ET), an imidazole-2-thione derivative of histidine betaine, is generally considered an antioxidant. Important antioxidants are typically regenerated from their oxidized products, to prevent the interceptors from being lost after a single chemical reaction with a reactive oxygen species. However, no mechanism for the complete regeneration of ET has yet been uncovered. Here we define a non-enzymatic multi-step cycle for the regeneration of ET after reaction with singlet oxygen (1O2). All reaction steps were verified by density functional theory computations. Four molecules of GSH are used per turn to detoxify 1O2 to water. Pure 1O2 was generated by thermolysis at 37 °C of the endoperoxide DHPNO2. Addition of 1 mM ET to 10 mM DHPNO2 and 10 mM GSH increased the production of oxidized GSH (GSSG), measured by LC-MS/MS, by a factor of 26 (water) and 28 (D2O), respectively. In the same assay, the ring of ET alone was able to drive the cycle at equal speed; thus, the zwitterionic amino acid backbone was not involved. Our data suggest that ET reacts at least 4-fold faster with 1O2 than ascorbic acid. ET must now be viewed as tightly linked with the GSH/GSSG redox couple. The necessary thiol foundation is present in all mammalian and vertebrate cells, and also in all species that generate ET, such as cyanobacteria, mycobacteria, and fungi. Regeneration provides a decisive advantage for ET over other reactive, but non-recoverable, compounds. Our findings substantiate the importance of ET for the eradication of noxious 1O2.
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Affiliation(s)
- Mhmd Oumari
- Department of Pharmacology, University of Cologne, Gleueler Straße 24, 50931, Cologne, Germany
| | - Bernd Goldfuss
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939, Cologne, Germany
| | - Christopher Stoffels
- Department of Pharmacology, University of Cologne, Gleueler Straße 24, 50931, Cologne, Germany
| | - Hans-Günther Schmalz
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939, Cologne, Germany
| | - Dirk Gründemann
- Department of Pharmacology, University of Cologne, Gleueler Straße 24, 50931, Cologne, Germany.
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19
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Tucker RAJ, Cheah IK, Halliwell B. Specificity of the ergothioneine transporter natively expressed in HeLa cells. Biochem Biophys Res Commun 2019; 513:22-27. [PMID: 30929922 DOI: 10.1016/j.bbrc.2019.02.122] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 02/22/2019] [Indexed: 01/23/2023]
Abstract
Ergothioneine is a biologically important compound that has been shown to be transported by the organic cation transporter novel type 1 (OCTN1). Following this discovery, a variety of alternate functions for OCTN1 have been suggested including an integral function in the extra-neuronal cholinergic system. The present study reaffirms the primacy of ergothioneine over these alternate substrates using natively expressed OCTN1 in HeLa cells. Besides the general transport inhibitors, quinidine, verapamil and pyrilamine no other putative substrate inhibited ergothioneine transport significantly, with only a slight inhibition demonstrated by carnitine. Even compounds structurally similar to ergothioneine failed to inhibit ergothioneine uptake, suggesting high selectivity of OCTN1. Ergothioneine was found to be avidly accumulated even at low concentrations (300 nM) by HeLa cells.
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Affiliation(s)
- Robert A J Tucker
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 28 Medical Drive, Singapore
| | - Irwin K Cheah
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 28 Medical Drive, Singapore
| | - Barry Halliwell
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 28 Medical Drive, Singapore.
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20
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Development of an LC⁻Tandem Mass Spectrometry Method for the Quantitative Analysis of Hercynine in Human Whole Blood. Molecules 2018; 23:molecules23123326. [PMID: 30558219 PMCID: PMC6321398 DOI: 10.3390/molecules23123326] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 12/13/2018] [Accepted: 12/13/2018] [Indexed: 11/17/2022] Open
Abstract
Given that the peculiar redox behavior of ergothioneine involves a rapid regeneration process, the measurement of its precursor and redox metabolite hercynine could be particularly useful in assessing its role in oxidative stress or other biological processes. Thus, a LC-MS/MS method for the determination of hercynine concentrations in whole blood was developed. After lysis of red blood cells by cold water, samples were filtered on micro concentrators at a controlled temperature of 4 °C. The clear filtered fluid was then treated with diethylpyrocarbonate to derivatize hercynine for the analysis by LC-MS/MS. The derivatized analyte was isocratically separated as a carbethoxy derivative on a C18 column with a mobile phase of an aqueous 0.1% v/v formic acid and acetonitrile (95:5). Effluents were monitored by MRM transitions at m/z 270.28→95 and 273.21→95 for hercynine and its deuterated counterpart, respectively. No cross-talk between MRM transitions was observed and a good linearity was found within a range of 35–1120 nmol/L. The LOD and LOQ were, respectively, 10.30 and 31.21 nmol/L with an intraday and intermediate precision below 7%. The average hercynine concentration in whole blood from 30 healthy male volunteers (aged 77 ± 12 years) was 178.5 ± 118.1 nmol/L. Overall, the method is easy to perform, allowing a rapid and accurate assessment of whole blood concentrations of hercynine.
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21
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Combination Metabolomics Approach for Identifying Endogenous Substrates of Carnitine/Organic Cation Transporter OCTN1. Pharm Res 2018; 35:224. [PMID: 30280275 DOI: 10.1007/s11095-018-2507-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 09/18/2018] [Indexed: 01/02/2023]
Abstract
PURPOSE Solute carrier SLC22A4 encodes the carnitine/organic cation transporter OCTN1 and is associated with inflammatory bowel disease, although little is known about how this gene is linked to pathogenesis. The aim of the present study was to identify endogenous substrates that are associated with gastrointestinal inflammation. METHODS HEK293/OCTN1 and mock cells were incubated with colon extracts isolated from dextran sodium sulfate-induced colitis mice; the subsequent cell lysates were mixed with the amino group selective reagent 3-aminopyridyl-N-hydroxysuccinimidyl carbamate (APDS), to selectively label OCTN1 substrates. Precursor ion scanning against the fragment ion of APDS was then used to identify candidate OCTN1 substrates. RESULTS Over 10,000 peaks were detected by precursor ion scanning; m/z 342 had a higher signal in HEK293/OCTN1 compared to mock cells. This peak was detected as a divalent ion that contained four APDS-derived fragments and was identified as spermine. Spermine concentration in peripheral blood mononuclear cells from octn1 gene knockout mice (octn1-/-) was significantly lower than in wild-type mice. Lipopolysaccharide-induced gene expression of inflammatory cytokines in peritoneal macrophages from octn1-/- mice was lower than in wild-type mice. CONCLUSIONS The combination metabolomics approach can provide a novel tool to identify endogenous substrates of OCTN1.
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22
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Naowarojna N, Cheng R, Chen L, Quill M, Xu M, Zhao C, Liu P. Mini-Review: Ergothioneine and Ovothiol Biosyntheses, an Unprecedented Trans-Sulfur Strategy in Natural Product Biosynthesis. Biochemistry 2018; 57:3309-3325. [PMID: 29589901 DOI: 10.1021/acs.biochem.8b00239] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
As one of the most abundant elements on earth, sulfur is part of many small molecular metabolites and is key to their biological activities. Over the past few decades, some general strategies have been discovered for the incorporation of sulfur into natural products. In this review, we summarize recent efforts in elucidating the biosynthetic details for two sulfur-containing metabolites, ergothioneine and ovothiol. Their biosyntheses involve an unprecedented trans-sulfur strategy, a combination of a mononuclear non-heme iron enzyme-catalyzed oxidative C-S bond formation reaction and a PLP enzyme-mediated C-S lyase reaction.
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Affiliation(s)
- Nathchar Naowarojna
- Department of Chemistry , Boston University , Boston , Massachusetts 02215 , United States
| | - Ronghai Cheng
- Department of Chemistry , Boston University , Boston , Massachusetts 02215 , United States
| | - Li Chen
- Department of Chemistry , Boston University , Boston , Massachusetts 02215 , United States.,Key Laboratory of Combinatory Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences , Wuhan University , Wuhan , Hubei 430072 , People's Republic of China
| | - Melissa Quill
- Department of Chemistry , Boston University , Boston , Massachusetts 02215 , United States
| | - Meiling Xu
- Department of Chemistry , Boston University , Boston , Massachusetts 02215 , United States
| | - Changming Zhao
- Department of Chemistry , Boston University , Boston , Massachusetts 02215 , United States.,Key Laboratory of Combinatory Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences , Wuhan University , Wuhan , Hubei 430072 , People's Republic of China
| | - Pinghua Liu
- Department of Chemistry , Boston University , Boston , Massachusetts 02215 , United States
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23
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l-Ergothioneine improves the developmental potential of in vitro sheep embryos without influencing OCTN1-mediated cross-membrane transcript expression. ZYGOTE 2018; 26:149-161. [DOI: 10.1017/s0967199418000047] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
SummaryThe objective of the study was to investigate the effect of l-ergothioneine (l-erg) (5 mM or 10 mM) supplementation in maturation medium on the developmental potential and OCTN1-dependant l-erg-mediated (10 mM) change in mRNA abundance of apoptotic (Bcl2, Bax, Casp3 and PCNA) and antioxidant (GPx, SOD1, SOD2 and CAT) genes in sheep oocytes and developmental stages of embryos produced in vitro. Oocytes matured with l-erg (10 mM) reduced their embryo toxicity by decreasing intracellular ROS and increasing intracellular GSH in matured oocytes that in turn improved developmental potential, resulting in significantly (P < 0.05) higher percentages of cleavage (53.72% vs 38.86, 46.56%), morulae (34.36% vs 20.62, 25.84%) and blastocysts (14.83% vs 6.98, 9.26%) compared with other lower concentrations (0 mM and 5 mM) of l-erg without change in maturation rate. l-Erg (10 mM) treatment did not influence the mRNA abundance of the majority of apoptotic and antioxidant genes studied in the matured oocytes and developmental stages of embryo. A gene expression study found that the SLC22A4 gene that encodes OCTN1, an integral membrane protein and specific transporter of l-erg was not expressed in oocytes and developmental stages of embryos. Therefore it was concluded from the study that although there was improvement in the developmental potential of sheep embryos by l-erg supplementation in maturation medium, there was no change in the expression of the majority of the genes studied due to the absence of the SLC22A4 gene in oocytes and embryos that encode OCTN1, which is responsible for transportation of l-erg across the membrane to alter gene expression.
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24
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Tschirka J, Kreisor M, Betz J, Gründemann D. Substrate Selectivity Check of the Ergothioneine Transporter. Drug Metab Dispos 2018. [PMID: 29530864 DOI: 10.1124/dmd.118.080440] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The candidate vitamin ergothioneine (ET) is a unique antioxidant. Expression of the ET transporter (ETT) (gene symbol SLC22A4) in distinct cells is thought to signal intracellular ET activity, since we have previously shown that the ETT is highly selective for ET. Unfortunately, some continue to hold the ETT as a relevant drug transporter, using the misleading functional name OCTN1, novel organic cation transporter. The present study was provoked by two recent reports in which new ETT substrates were declared. Astonishingly, the transport efficiencies (TEs) of ETT for saracatinib and some nucleoside drugs were as high as the TE for ET. Here we examined, based on regulated expression of ETT from human and rat in 293 cells and liquid chromatography-mass spectrometry quantification, the transport of several drugs. With the nucleosides cytarabine, gemcitabine, 2'-deoxycytidine, and 2'-deoxyadenosine, and the drugs saracatinib, ipratropium, metformin, and oxaliplatin, the uptake into cells expressing ETT was not increased over control cells. ETT-mediated uptake of gabapentin was detectable, but the TE was approximately 100-fold lower than the TE for ergothioneine (50-200 µl/min per milligram of protein). In conclusion, the ETT remains highly specific for its physiologic substrate ergothioneine. Our results contradict several reports on additional substrates. The ETT does not provide multiple substrate specificities, and it is not a transporter of cationic drugs. Only compounds that are related to ET in substructure-for example, gabapentin, carnitine, and TEA-can be transported, but with very low efficiency. Thus, ETT persists as a specific molecular indicator of ET activity.
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Affiliation(s)
- Julia Tschirka
- Department of Pharmacology, University of Cologne, Cologne, Germany
| | - Madlen Kreisor
- Department of Pharmacology, University of Cologne, Cologne, Germany
| | - Janina Betz
- Department of Pharmacology, University of Cologne, Cologne, Germany
| | - Dirk Gründemann
- Department of Pharmacology, University of Cologne, Cologne, Germany
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Tang RMY, Cheah IKM, Yew TSK, Halliwell B. Distribution and accumulation of dietary ergothioneine and its metabolites in mouse tissues. Sci Rep 2018; 8:1601. [PMID: 29371632 PMCID: PMC5785509 DOI: 10.1038/s41598-018-20021-z] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 01/11/2018] [Indexed: 01/31/2023] Open
Abstract
L-ergothioneine (ET) is a diet-derived amino acid that accumulates at high concentrations in animals and humans. Numerous studies have highlighted its antioxidant abilities in vitro, and possible cytoprotective capabilities in vivo. We investigated the uptake and distribution of ET in various organs by a highly sensitive and specific liquid chromatography coupled tandem mass spectrometry (LC-MS/MS) technique, both before and after oral administration of pure ET (35 and 70 mg/kg/day for 1, 7, and 28 days) to male C57BL6J mice. ET primarily concentrates in the liver and whole blood, and also in spleen, kidney, lung, heart, intestines, eye, and brain tissues. Strong correlations were found between ET and its putative metabolites - hercynine, ET-sulfonate (ET-SO3H), and S-methyl ET. Hercynine accumulates in the brain after prolonged ET administration. This study demonstrates the uptake and distribution of ET and provides a foundation for future studies with ET to target oxidative damage in a range of tissues in human diseases.
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Affiliation(s)
- Richard Ming Yi Tang
- National University of Singapore Graduate School for Integrative Sciences and Engineering, Singapore, Singapore
| | - Irwin Kee-Mun Cheah
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 28 Medical Drive, Singapore, Singapore
| | - Terry Shze Keong Yew
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 28 Medical Drive, Singapore, Singapore
| | - Barry Halliwell
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 28 Medical Drive, Singapore, Singapore.
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Stoffels C, Oumari M, Perrou A, Termath A, Schlundt W, Schmalz HG, Schäfer M, Wewer V, Metzger S, Schömig E, Gründemann D. Ergothioneine stands out from hercynine in the reaction with singlet oxygen: Resistance to glutathione and TRIS in the generation of specific products indicates high reactivity. Free Radic Biol Med 2017; 113:385-394. [PMID: 29074402 DOI: 10.1016/j.freeradbiomed.2017.10.372] [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: 07/25/2017] [Revised: 10/17/2017] [Accepted: 10/19/2017] [Indexed: 12/24/2022]
Abstract
The candidate vitamin ergothioneine (ET), an imidazole-2-thione derivative of histidine betaine, is generally considered an antioxidant. However, the precise physiological role of ET is still unresolved. Here, we investigated in vitro the hypothesis that ET serves specifically to eradicate noxious singlet oxygen (1O2). Pure 1O2 was generated by thermolysis at 37°C of N,N'-di(2,3-dihydroxypropyl)-1,4-naphthalenedipropanamide 1,4-endoperoxide (DHPNO2). Assays of DHPNO2 with ET or hercynine (= ET minus sulfur) at pH 7.4 were analyzed by LC-MS in full scan mode to detect products. Based on accurate mass and product ion scan data, several products were identified and then quantitated as a function of time by selected reaction monitoring. All products of hercynine contained, after a [4+2] cycloaddition of 1O2, a carbonyl at position 2 of the imidazole ring. By contrast, because of the doubly bonded sulfur, we infer from the products of ET as the initial intermediates a 4,5-dioxetane (after [2+2] cycloaddition) and hydroperoxides at position 4 and 5 (after Schenck ene reactions). The generation of single products from ET, but not from hercynine, was fully resistant to a large excess of tris(hydroxymethyl)aminomethane (TRIS) or glutathione (GSH). This suggests that 1O2 markedly favors ET over GSH (at least 50-fold) and TRIS (at least 250-fold) for the initial reaction. Loss of ET was almost abolished in 5mM GSH, but not in 25mM TRIS. Regeneration of ET seems feasible, since some ET products - by contrast to hercynine products - decomposed easily in the MS collision cell to become aromatic again.
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Affiliation(s)
- Christopher Stoffels
- Department of Pharmacology, University of Cologne, Gleueler Straße 24, 50931 Cologne, Germany
| | - Mhmd Oumari
- Department of Pharmacology, University of Cologne, Gleueler Straße 24, 50931 Cologne, Germany
| | - Aris Perrou
- Department of Pharmacology, University of Cologne, Gleueler Straße 24, 50931 Cologne, Germany
| | - Andreas Termath
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939 Cologne, Germany
| | - Waldemar Schlundt
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939 Cologne, Germany
| | - Hans-Günther Schmalz
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939 Cologne, Germany
| | - Mathias Schäfer
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939 Cologne, Germany
| | - Vera Wewer
- MS-Platform Biocenter, Cluster of Excellence on Plant Science (CEPLAS), University of Cologne, Zülpicher Straße 47b, 50674 Cologne, Germany
| | - Sabine Metzger
- MS-Platform Biocenter, Cluster of Excellence on Plant Science (CEPLAS), University of Cologne, Zülpicher Straße 47b, 50674 Cologne, Germany
| | - Edgar Schömig
- Department of Pharmacology, University of Cologne, Gleueler Straße 24, 50931 Cologne, Germany
| | - Dirk Gründemann
- Department of Pharmacology, University of Cologne, Gleueler Straße 24, 50931 Cologne, Germany.
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Abstract
Ergothioneine (ESH), the betaine of 2-mercapto-L-histidine, is a water-soluble naturally occurring amino acid with antioxidant properties. ESH accumulates in several human and animal tissues up to millimolar concentration through its high affinity transporter, namely the organic cation transporter 1 (OCTN1). ESH, first isolated from the ergot fungus (Claviceps purpurea), is synthesized only by Actinomycetales and non-yeast-like fungi. Plants absorb ESH via symbiotic associations between their roots and soil fungi, whereas mammals acquire it solely from dietary sources. Numerous evidence demonstrated the antioxidant and cytoprotective effects of ESH, including protection against cardiovascular diseases, chronic inflammatory conditions, ultraviolet radiation damages, and neuronal injuries. Although more than a century after its discovery has gone by, our understanding on the in vivo ESH mechanism is limited and this compound still intrigues researchers. However, recent evidence about differences in chemical redox behavior between ESH and alkylthiols, such as cysteine and glutathione, has opened new perspectives on the role of ESH during oxidative damage. In this short review, we discuss the role of ESH in the complex machinery of the cellular antioxidant defense focusing on the current knowledge on its chemical mechanism of action in the protection against cardiovascular disease.
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28
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Pahila J, Kaneda H, Nagasaka R, Koyama T, Ohshima T. Effects of ergothioneine-rich mushroom extracts on lipid oxidation and discoloration in salmon muscle stored at low temperatures. Food Chem 2017; 233:273-281. [DOI: 10.1016/j.foodchem.2017.04.130] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 04/11/2017] [Accepted: 04/19/2017] [Indexed: 10/19/2022]
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29
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Cheah IK, Tang RMY, Yew TSZ, Lim KHC, Halliwell B. Administration of Pure Ergothioneine to Healthy Human Subjects: Uptake, Metabolism, and Effects on Biomarkers of Oxidative Damage and Inflammation. Antioxid Redox Signal 2017; 26:193-206. [PMID: 27488221 DOI: 10.1089/ars.2016.6778] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AIM We investigated the uptake and pharmacokinetics of l-ergothioneine (ET), a dietary thione with free radical scavenging and cytoprotective capabilities, after oral administration to humans, and its effect on biomarkers of oxidative damage and inflammation. RESULTS After oral administration, ET is avidly absorbed and retained by the body with significant elevations in plasma and whole blood concentrations, and relatively low urinary excretion (<4% of administered ET). ET levels in whole blood were highly correlated to levels of hercynine and S-methyl-ergothioneine, suggesting that they may be metabolites. After ET administration, some decreasing trends were seen in biomarkers of oxidative damage and inflammation, including allantoin (urate oxidation), 8-hydroxy-2'-deoxyguanosine (DNA damage), 8-iso-PGF2α (lipid peroxidation), protein carbonylation, and C-reactive protein. However, most of the changes were non-significant. INNOVATION This is the first study investigating the administration of pure ET to healthy human volunteers and monitoring its uptake and pharmacokinetics. This compound is rapidly gaining attention due to its unique properties, and this study lays the foundation for future human studies. CONCLUSION The uptake and retention of ET by the body suggests an important physiological function. The decreasing trend of oxidative damage biomarkers is consistent with animal studies suggesting that ET may function as a major antioxidant but perhaps only under conditions of oxidative stress. Antioxid. Redox Signal. 26, 193-206.
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Affiliation(s)
- Irwin K Cheah
- 1 Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore , Singapore .,3 Centre for Life Sciences, National University of Singapore, Singapore
| | - Richard M Y Tang
- 1 Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore , Singapore .,3 Centre for Life Sciences, National University of Singapore, Singapore
| | - Terry S Z Yew
- 1 Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore , Singapore .,3 Centre for Life Sciences, National University of Singapore, Singapore
| | - Keith H C Lim
- 2 Department of Radiation Oncology, National University Cancer Institute Singapore, National University Hospital , Singapore
| | - Barry Halliwell
- 1 Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore , Singapore .,3 Centre for Life Sciences, National University of Singapore, Singapore
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Sotgia S, Mangoni AA, Forteschi M, Murphy RB, Elliot D, Sotgiu E, Pintus G, Carru C, Zinellu A. Identification of the Main Intermediate Precursor of l-Ergothioneine Biosynthesis in Human Biological Specimens. Molecules 2016; 21:molecules21101298. [PMID: 27689978 PMCID: PMC6272924 DOI: 10.3390/molecules21101298] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 09/10/2016] [Accepted: 09/23/2016] [Indexed: 12/26/2022] Open
Abstract
A capillary electrophoresis coupled to tandem mass spectrometry (CE–MS/MS) has been used to make a qualitative determination of hercynine—the main precursor of l-ergothioneine biosynthesis—in some key human biological specimens, such as urine, whole blood, plasma, and saliva. From semiquantitative analysis results, the highest concentrations of hercynine were detected in saliva and whole blood, whereas much lower concentrations were measured in urine and plasma. Whole blood was the biological matrix with the highest concentration of l-ergothioneine followed by plasma, saliva, and urine. The antioxidant effects attributed to l-ergothioneine, along with its peculiar antioxidant mechanism, offer a possible explanation for the presence of the hercynine, as well as its concentration, in the considered biological matrices.
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Affiliation(s)
- Salvatore Sotgia
- Department of Biomedical Sciences, School of Medicine, University of Sassari, Sassari 07100, Italy.
| | - Arduino A Mangoni
- Department of Clinical Pharmacology, School of Medicine, Flinders University and Flinders Medical Centre, Adelaide SA 5042, Australia.
| | - Mauro Forteschi
- Department of Biomedical Sciences, School of Medicine, University of Sassari, Sassari 07100, Italy.
| | - Rhys B Murphy
- Department of Clinical Pharmacology, School of Medicine, Flinders University and Flinders Medical Centre, Adelaide SA 5042, Australia.
| | - David Elliot
- Department of Clinical Pharmacology, School of Medicine, Flinders University and Flinders Medical Centre, Adelaide SA 5042, Australia.
| | - Elisabetta Sotgiu
- Department of Biomedical Sciences, School of Medicine, University of Sassari, Sassari 07100, Italy.
| | - Gianfranco Pintus
- Department of Biomedical Sciences, School of Medicine, University of Sassari, Sassari 07100, Italy.
- Department of Biomedical Sciences, College of Health Sciences, Qatar University, Doha 2713, Qatar.
| | - Ciriaco Carru
- Department of Biomedical Sciences, School of Medicine, University of Sassari, Sassari 07100, Italy.
- Quality Control Unit, University Hospital Sassari (AOU), Sassari 07100, Italy.
| | - Angelo Zinellu
- Department of Biomedical Sciences, School of Medicine, University of Sassari, Sassari 07100, Italy.
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31
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Halliwell B, Cheah IK, Drum CL. Ergothioneine, an adaptive antioxidant for the protection of injured tissues? A hypothesis. Biochem Biophys Res Commun 2016; 470:245-250. [PMID: 26772879 DOI: 10.1016/j.bbrc.2015.12.124] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 12/30/2015] [Indexed: 12/30/2022]
Abstract
Ergothioneine (ET) is a diet-derived, thiolated derivative of histidine with antioxidant properties. Although ET is produced only by certain fungi and bacteria, it can be found at high concentrations in certain human and animal tissues and is absorbed through a specific, high affinity transporter (OCTN1). In liver, heart, joint and intestinal injury, elevated ET concentrations have been observed in injured tissues. The physiological role of ET remains unclear. We thus review current literature to generate a specific hypothesis: that the accumulation of ET in vivo is an adaptive mechanism, involving the regulated uptake and concentration of an exogenous natural compound to minimize oxidative damage.
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Affiliation(s)
- Barry Halliwell
- Department of Biochemistry, National University of Singapore, Singapore.
| | - Irwin K Cheah
- Department of Biochemistry, National University of Singapore, Singapore
| | - Chester L Drum
- Cardiovascular Research Institute, National University Health System, Singapore; Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Translational Laboratory in Genetic Medicine, 8A Biomedical Grove, Immunos, Level 5, 138648, Singapore
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32
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Alamgir KM, Masuda S, Fujitani Y, Fukuda F, Tani A. Production of ergothioneine by Methylobacterium species. Front Microbiol 2015; 6:1185. [PMID: 26579093 PMCID: PMC4621440 DOI: 10.3389/fmicb.2015.01185] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 10/12/2015] [Indexed: 01/09/2023] Open
Abstract
Metabolomic analysis revealed that Methylobacterium cells accumulate a large amount of ergothioneine (EGT), which is a sulfur-containing, non-proteinogenic, antioxidative amino acid derived from histidine. EGT biosynthesis and its role in methylotrophy and physiology for plant surface-symbiotic Methylobacterium species were investigated in this study. Almost all Methylobacterium type strains can synthesize EGT. We selected one of the most productive strains (M. aquaticum strain 22A isolated from a moss), and investigated the feasibility of fermentative EGT production through optimization of the culture condition. Methanol as a carbon source served as the best substrate for production. The productivity reached up to 1000 μg/100 ml culture (1200 μg/g wet weight cells, 6.3 mg/g dry weight) in 38 days. Next, we identified the genes (egtBD) responsible for EGT synthesis, and generated a deletion mutant defective in EGT production. Compared to the wild type, the mutant showed better growth on methanol and on the plant surface as well as severe susceptibility to heat treatment and irradiation of ultraviolet (UV) and sunlight. These results suggested that EGT is not involved in methylotrophy, but is involved in their phyllospheric lifestyle fitness of the genus in natural conditions.
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Affiliation(s)
- Kabir M Alamgir
- Group of Plant-Microbe Interactions, Institute of Plant Science and Resources, Okayama University Okayama, Japan
| | - Sachiko Masuda
- Group of Plant-Microbe Interactions, Institute of Plant Science and Resources, Okayama University Okayama, Japan ; Advanced Low Carbon Technology Research and Development Program, Japan Science and Technology Agency Tokyo, Japan
| | - Yoshiko Fujitani
- Group of Plant-Microbe Interactions, Institute of Plant Science and Resources, Okayama University Okayama, Japan
| | - Fumio Fukuda
- Laboratory of Pomology, Graduate School of Environmental and Life Science, Okayama University Okayama, Japan
| | - Akio Tani
- Group of Plant-Microbe Interactions, Institute of Plant Science and Resources, Okayama University Okayama, Japan
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33
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Pfeiffer C, Bach M, Bauer T, Campos da Ponte J, Schömig E, Gründemann D. Knockout of the ergothioneine transporter ETT in zebrafish results in increased 8-oxoguanine levels. Free Radic Biol Med 2015; 83:178-85. [PMID: 25746775 DOI: 10.1016/j.freeradbiomed.2015.02.026] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 02/02/2015] [Accepted: 02/24/2015] [Indexed: 02/02/2023]
Abstract
Ergothioneine (ET) is a natural compound that humans and other vertebrates must absorb from dietary sources. In general, ET is considered an intracellular antioxidant. However, the precise physiological purpose of ET and the consequences of ET deficiency are still unclear. The ergothioneine transporter ETT (human gene symbol SLC22A4) is a highly specific transporter for the uptake of ET. Here, we sought to identify and knock out ETT from zebrafish (Danio rerio) to determine the function of ET. We cloned and assayed three related proteins from zebrafish, only one of which catalyzed the uptake of ET. RT-PCR analysis revealed that the protein is strongly expressed in the skin, brain, kidney, intestine, and eye. In ETT-knockout animals generated by retroviral insertion into exon 1, ET content was reduced by more than 1000-fold compared to the wild type. Thus, ETT is the sole transporter responsible for uptake of ET into zebrafish. ETT-knockout fish did not exhibit obvious differences in morphology or behavior. In whole-fish homogenates, an increase in 4-hydroxy-2,3-trans-nonenal and malondialdehyde was observed, but only after stress caused by incubation with Pb(2+) or Cu(2+). Comparison of unstressed fish at the level of small molecules by LC-MS difference shading revealed a 3.8-fold increase in 8-oxoguanine (8-oxo-7,8-dihydroguanine) in the skin of ETT-knockout animals. Our knockout represents a new model for examining the consequences of complete absence of ET. Based on the phenotype observed here, we hypothesize that the specific purpose of ET could be to eliminate singlet oxygen.
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Affiliation(s)
- Carolin Pfeiffer
- Department of Pharmacology, University of Cologne, 50931 Cologne, Germany
| | - Markus Bach
- Department of Pharmacology, University of Cologne, 50931 Cologne, Germany
| | - Tim Bauer
- Department of Pharmacology, University of Cologne, 50931 Cologne, Germany
| | | | - Edgar Schömig
- Department of Pharmacology, University of Cologne, 50931 Cologne, Germany
| | - Dirk Gründemann
- Department of Pharmacology, University of Cologne, 50931 Cologne, Germany.
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34
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Shimizu T, Masuo Y, Takahashi S, Nakamichi N, Kato Y. Organic cation transporter Octn1-mediated uptake of food-derived antioxidant ergothioneine into infiltrating macrophages during intestinal inflammation in mice. Drug Metab Pharmacokinet 2015; 30:231-9. [PMID: 26003890 DOI: 10.1016/j.dmpk.2015.02.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Revised: 02/10/2015] [Accepted: 02/12/2015] [Indexed: 01/14/2023]
Abstract
OCTN1/SLC22A4 is expressed on apical membranes of small intestine, and is involved in gastrointestinal absorption of its substrates, including the food-derived antioxidant ergothioneine (ERGO). ERGO concentration in circulating blood of patients with inflammatory bowel disease (Crohn's disease) is lower than that in healthy volunteers; thus, circulating ERGO is a potential diagnostic marker, although the mechanisms underlying low ERGO concentration in patients are unknown. Here, we focused on intestinal macrophages, which infiltrate sites of inflammation, and examined possible first-pass uptake of ERGO by macrophages. ERGO concentration in blood was lower in mice with dextran sodium sulfate (DSS)-induced colitis than in controls. On the other hand, expression of octn1 gene product and ERGO concentration in intestinal tissues of DSS-treated mice were higher than in controls. Interestingly, lamina propria mononuclear cells (LPMCs) isolated from DSS-treated mice contained ERGO and showed [(3)H]ERGO uptake and Octn1 expression, whereas ERGO was undetectable in LPMCs of control mice. Functional expression of OCTN1 was also confirmed in LPS-stimulated human macrophage-like cell line, THP-1. In conclusion, OCTN1 is functionally expressed on activated intestinal macrophages, and ERGO uptake into these immune cells could contribute at least in part to the altered disposition of ERGO in intestinal inflammation.
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Affiliation(s)
- Takuya Shimizu
- Faculty of Pharmacy, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa 920-1192, Japan
| | - Yusuke Masuo
- Faculty of Pharmacy, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa 920-1192, Japan
| | - Saki Takahashi
- Faculty of Pharmacy, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa 920-1192, Japan
| | - Noritaka Nakamichi
- Faculty of Pharmacy, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa 920-1192, Japan
| | - Yukio Kato
- Faculty of Pharmacy, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa 920-1192, Japan.
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35
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Servillo L, Castaldo D, Casale R, D'Onofrio N, Giovane A, Cautela D, Balestrieri ML. An uncommon redox behavior sheds light on the cellular antioxidant properties of ergothioneine. Free Radic Biol Med 2015; 79:228-36. [PMID: 25483556 DOI: 10.1016/j.freeradbiomed.2014.11.017] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 11/18/2014] [Accepted: 11/20/2014] [Indexed: 01/17/2023]
Abstract
Ergothioneine (ESH), an aromatic thiol occurring in the human diet and which accumulates in particular cells, is believed to act as an antioxidant. However, its redox mechanism remains unclear and it does not seem to provide any advantage compared to other antioxidants, such as alkylthiols, which are better reducing agents and generally present in cells at higher levels. Here, we investigated by ESI-MS the products of ESH oxidation produced by neutrophils during oxidative burst and, to further elucidate ESH redox behavior, we also analyzed the oxidation products of the reaction of ESH with hypochlorite in cell-free solutions. Indeed, neutrophils are the main source of hypochlorite in humans. Furthermore, we also tested other biologically relevant oxidants, such as peroxynitrite and hydrogen peroxide. Our results indicate that treatment of human neutrophils with phorbol 12-myristate 13-acetate in the presence of ESH leads to a remarkable production of the sulfonated form (ESO3H), a compound never described before, and hercynine (EH), the desulfurated form of ESH. Similar results were obtained when ESH was subjected to cell-free oxidation in the presence of hypochlorite, as well as hydrogen peroxide or peroxynitrite. Furthermore, when the disulfide of ESH was reacted with those oxidants, we found that it was also oxidized, with production of EH and ESO3H, whose amount was dependent on the oxidant strength. These data reveal a unique ESH redox behavior, entirely different from that of alkylthiols, and suggest a mechanism, so far overlooked, through which ESH performs its antioxidant action in cells.
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Affiliation(s)
- Luigi Servillo
- Dipartimento di Biochimica, Biofisica e Patologia Generale, Seconda Università degli Studi di Napoli, 7-80138 Napoli, Italy.
| | - Domenico Castaldo
- Stazione Sperimentale per le Industrie delle Essenze e dei Derivati dagli Agrumi, Azienda Speciale della Camera di Commercio di Reggio Calabria, 12-89125 Reggio Calabria, Italy
| | - Rosario Casale
- Dipartimento di Biochimica, Biofisica e Patologia Generale, Seconda Università degli Studi di Napoli, 7-80138 Napoli, Italy
| | - Nunzia D'Onofrio
- Dipartimento di Biochimica, Biofisica e Patologia Generale, Seconda Università degli Studi di Napoli, 7-80138 Napoli, Italy
| | - Alfonso Giovane
- Dipartimento di Biochimica, Biofisica e Patologia Generale, Seconda Università degli Studi di Napoli, 7-80138 Napoli, Italy
| | - Domenico Cautela
- Stazione Sperimentale per le Industrie delle Essenze e dei Derivati dagli Agrumi, Azienda Speciale della Camera di Commercio di Reggio Calabria, 12-89125 Reggio Calabria, Italy
| | - Maria Luisa Balestrieri
- Dipartimento di Biochimica, Biofisica e Patologia Generale, Seconda Università degli Studi di Napoli, 7-80138 Napoli, Italy
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36
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Antioxidant property of edible mushrooms collected from Ethiopia. Food Chem 2014; 157:30-6. [DOI: 10.1016/j.foodchem.2014.02.014] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 01/14/2014] [Accepted: 02/03/2014] [Indexed: 11/19/2022]
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37
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Li RWS, Yang C, Sit ASM, Kwan YW, Lee SMY, Hoi MPM, Chan SW, Hausman M, Vanhoutte PM, Leung GPH. Uptake and protective effects of ergothioneine in human endothelial cells. J Pharmacol Exp Ther 2014; 350:691-700. [PMID: 25022513 DOI: 10.1124/jpet.114.214049] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Ergothioneine is a thiourea derivative of histidine found in food, especially mushrooms. Experiments in cell-free systems and chemical assays identified this compound as a powerful antioxidant. Experiments were designed to test the ability of endothelial cells to take up ergothioneine and hence benefit from protection against oxidative stress. Reverse-transcription polymerase chain reaction and Western blotting demonstrated transcription and translation of an ergothioneine transporter in human brain microvascular endothelial cells (HBMECs). Uptake of [(3)H]ergothioneine occurred by the organic cation transporter novel type-1 (OCTN-1), was sodium-dependent, and was reduced when expression of OCTN-1 was silenced by small interfering RNA (siRNA). The effect of ergothioneine on the production of reactive oxygen species (ROS) in HBMECs was measured using dichlorodihydrofluorescein and lucigenin, and the effect on cell viability was studied using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. ROS production and cell death induced by pyrogallol, xanthine oxidase plus xanthine, and high glucose were suppressed by ergothioneine. The antioxidant and cytoprotective effects of ergothioneine were abolished when OCTN-1 was silenced using siRNA. The expression of NADPH oxidase 1 was decreased, and those of glutathione reductase, catalase, and superoxide dismutase enhanced by the compound. In isolated rat basilar arteries, ergothioneine attenuated the reduction in acetylcholine-induced relaxation caused by pyrogallol, xanthine oxidase plus xanthine, or incubation in high glucose. Chronic treatment with the compound improved the response to acetylcholine in arteries of rats with streptozotocin-induced diabetes. In summary, ergothioneine is taken up by endothelial cells via OCTN-1, where the compound then protects against oxidative stress, curtailing endothelial dysfunction.
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Affiliation(s)
- Rachel W S Li
- State Key Laboratory for Pharmaceutical Biotechnologies and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong (R.W.S.L., A.S.M.S., P.M.V., G.P.H.L.); Ethnic Drug Screening and Pharmacology Center, Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China (C.Y.); School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong (Y.W.K.); Institute of Chinese Medical Sciences, University of Macau, Macao, China (S.M.Y.L., M.P.M.H.); State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong (S.W.C.); and Entia Biosciences Inc., Sherwood, Oregon (M.H.)
| | - C Yang
- State Key Laboratory for Pharmaceutical Biotechnologies and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong (R.W.S.L., A.S.M.S., P.M.V., G.P.H.L.); Ethnic Drug Screening and Pharmacology Center, Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China (C.Y.); School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong (Y.W.K.); Institute of Chinese Medical Sciences, University of Macau, Macao, China (S.M.Y.L., M.P.M.H.); State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong (S.W.C.); and Entia Biosciences Inc., Sherwood, Oregon (M.H.)
| | - Albert S M Sit
- State Key Laboratory for Pharmaceutical Biotechnologies and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong (R.W.S.L., A.S.M.S., P.M.V., G.P.H.L.); Ethnic Drug Screening and Pharmacology Center, Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China (C.Y.); School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong (Y.W.K.); Institute of Chinese Medical Sciences, University of Macau, Macao, China (S.M.Y.L., M.P.M.H.); State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong (S.W.C.); and Entia Biosciences Inc., Sherwood, Oregon (M.H.)
| | - Y W Kwan
- State Key Laboratory for Pharmaceutical Biotechnologies and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong (R.W.S.L., A.S.M.S., P.M.V., G.P.H.L.); Ethnic Drug Screening and Pharmacology Center, Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China (C.Y.); School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong (Y.W.K.); Institute of Chinese Medical Sciences, University of Macau, Macao, China (S.M.Y.L., M.P.M.H.); State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong (S.W.C.); and Entia Biosciences Inc., Sherwood, Oregon (M.H.)
| | - Simon M Y Lee
- State Key Laboratory for Pharmaceutical Biotechnologies and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong (R.W.S.L., A.S.M.S., P.M.V., G.P.H.L.); Ethnic Drug Screening and Pharmacology Center, Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China (C.Y.); School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong (Y.W.K.); Institute of Chinese Medical Sciences, University of Macau, Macao, China (S.M.Y.L., M.P.M.H.); State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong (S.W.C.); and Entia Biosciences Inc., Sherwood, Oregon (M.H.)
| | - Maggie P M Hoi
- State Key Laboratory for Pharmaceutical Biotechnologies and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong (R.W.S.L., A.S.M.S., P.M.V., G.P.H.L.); Ethnic Drug Screening and Pharmacology Center, Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China (C.Y.); School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong (Y.W.K.); Institute of Chinese Medical Sciences, University of Macau, Macao, China (S.M.Y.L., M.P.M.H.); State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong (S.W.C.); and Entia Biosciences Inc., Sherwood, Oregon (M.H.)
| | - S W Chan
- State Key Laboratory for Pharmaceutical Biotechnologies and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong (R.W.S.L., A.S.M.S., P.M.V., G.P.H.L.); Ethnic Drug Screening and Pharmacology Center, Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China (C.Y.); School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong (Y.W.K.); Institute of Chinese Medical Sciences, University of Macau, Macao, China (S.M.Y.L., M.P.M.H.); State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong (S.W.C.); and Entia Biosciences Inc., Sherwood, Oregon (M.H.)
| | - Marvin Hausman
- State Key Laboratory for Pharmaceutical Biotechnologies and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong (R.W.S.L., A.S.M.S., P.M.V., G.P.H.L.); Ethnic Drug Screening and Pharmacology Center, Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China (C.Y.); School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong (Y.W.K.); Institute of Chinese Medical Sciences, University of Macau, Macao, China (S.M.Y.L., M.P.M.H.); State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong (S.W.C.); and Entia Biosciences Inc., Sherwood, Oregon (M.H.)
| | - Paul M Vanhoutte
- State Key Laboratory for Pharmaceutical Biotechnologies and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong (R.W.S.L., A.S.M.S., P.M.V., G.P.H.L.); Ethnic Drug Screening and Pharmacology Center, Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China (C.Y.); School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong (Y.W.K.); Institute of Chinese Medical Sciences, University of Macau, Macao, China (S.M.Y.L., M.P.M.H.); State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong (S.W.C.); and Entia Biosciences Inc., Sherwood, Oregon (M.H.)
| | - George P H Leung
- State Key Laboratory for Pharmaceutical Biotechnologies and Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong (R.W.S.L., A.S.M.S., P.M.V., G.P.H.L.); Ethnic Drug Screening and Pharmacology Center, Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan Minzu University, Kunming, China (C.Y.); School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong (Y.W.K.); Institute of Chinese Medical Sciences, University of Macau, Macao, China (S.M.Y.L., M.P.M.H.); State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong (S.W.C.); and Entia Biosciences Inc., Sherwood, Oregon (M.H.)
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Feeney MJ, Dwyer J, Hasler-Lewis CM, Milner JA, Noakes M, Rowe S, Wach M, Beelman RB, Caldwell J, Cantorna MT, Castlebury LA, Chang ST, Cheskin LJ, Clemens R, Drescher G, Fulgoni VL, Haytowitz DB, Hubbard VS, Law D, Myrdal Miller A, Minor B, Percival SS, Riscuta G, Schneeman B, Thornsbury S, Toner CD, Woteki CE, Wu D. Mushrooms and Health Summit proceedings. J Nutr 2014; 144:1128S-36S. [PMID: 24812070 PMCID: PMC4056650 DOI: 10.3945/jn.114.190728] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The Mushroom Council convened the Mushrooms and Health Summit in Washington, DC, on 9-10 September 2013. The proceedings are synthesized in this article. Although mushrooms have long been regarded as health-promoting foods, research specific to their role in a healthful diet and in health promotion has advanced in the past decade. The earliest mushroom cultivation was documented in China, which remains among the top global mushroom producers, along with the United States, Italy, The Netherlands, and Poland. Although considered a vegetable in dietary advice, mushrooms are fungi, set apart by vitamin B-12 in very low quantity but in the same form found in meat, ergosterol converted with UV light to vitamin D2, and conjugated linoleic acid. Mushrooms are a rare source of ergothioneine as well as selenium, fiber, and several other vitamins and minerals. Some preclinical and clinical studies suggest impacts of mushrooms on cognition, weight management, oral health, and cancer risk. Preliminary evidence suggests that mushrooms may support healthy immune and inflammatory responses through interaction with the gut microbiota, enhancing development of adaptive immunity, and improved immune cell functionality. In addition to imparting direct nutritional and health benefits, analysis of U.S. food intake survey data reveals that mushrooms are associated with higher dietary quality. Also, early sensory research suggests that mushrooms blended with meats and lower sodium dishes are well liked and may help to reduce intakes of red meat and salt without compromising taste. As research progresses on the specific health effects of mushrooms, there is a need for effective communication efforts to leverage mushrooms to improve overall dietary quality.
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Affiliation(s)
- Mary Jo Feeney
- Consultant to the Food and Agriculture Industries, Los Altos, CA
| | - Johanna Dwyer
- Tufts Medical School and USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA
| | - Clare M. Hasler-Lewis
- Robert Mondavi Institute for Wine and Food Science, University of California, Davis, Davis, CA
| | - John A. Milner
- Beltsville Human Nutrition Research Center, Agricultural Research Service, USDA, Beltsville, MD
| | - Manny Noakes
- Commonwealth Scientific and Industrial Research Organization, Adelaide, Australia
| | | | | | - Robert B. Beelman
- Center for Plant and Mushroom Products for Health, Department of Food Science, The Pennsylvania State University, University Park, PA
| | | | - Margherita T. Cantorna
- Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA
| | - Lisa A. Castlebury
- Systematic Mycology and Microbiology Laboratory, Agricultural Research Service, USDA, Beltsville, MD
| | - Shu-Ting Chang
- The Chinese University of Hong Kong, McKellar, Australian Capital Territory, Australia
| | - Lawrence J. Cheskin
- Johns Hopkins Weight Management Center and Department of Health, Behavior and Society, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Roger Clemens
- International Center for Regulatory Science, School of Pharmacy, University of Southern California, Los Angeles, CA
| | | | | | - David B. Haytowitz
- Nutrient Data Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, USDA, Beltsville, MD
| | - Van S. Hubbard
- NIH Division of Nutrition Research Coordination and the National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Department of Health and Human Services, Bethesda, MD
| | - David Law
- Gourmet Mushrooms, Inc, Sebastopol, CA
| | | | | | - Susan S. Percival
- Food Science and Human Nutrition Department, University of Florida, Gainesville, FL
| | - Gabriela Riscuta
- Nutritional Science Research Group, Division of Cancer Prevention, National Cancer Institute, NIH, Rockville, MD
| | | | - Suzanne Thornsbury
- Market and Trade Economics Division, Economic Research Service, USDA, Washington, DC
| | | | | | - Dayong Wu
- Nutritional Immunology Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging and Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA
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39
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Kuypers FA. Hemoglobin S Polymerization and Red Cell Membrane Changes. Hematol Oncol Clin North Am 2014; 28:155-79. [DOI: 10.1016/j.hoc.2013.12.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Ishimoto T, Nakamichi N, Hosotani H, Masuo Y, Sugiura T, Kato Y. Organic cation transporter-mediated ergothioneine uptake in mouse neural progenitor cells suppresses proliferation and promotes differentiation into neurons. PLoS One 2014; 9:e89434. [PMID: 24586778 PMCID: PMC3934899 DOI: 10.1371/journal.pone.0089434] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 01/11/2014] [Indexed: 01/11/2023] Open
Abstract
The aim of the present study is to clarify the functional expression and physiological role in neural progenitor cells (NPCs) of carnitine/organic cation transporter OCTN1/SLC22A4, which accepts the naturally occurring food-derived antioxidant ergothioneine (ERGO) as a substrate in vivo. Real-time PCR analysis revealed that mRNA expression of OCTN1 was much higher than that of other organic cation transporters in mouse cultured cortical NPCs. Immunocytochemical analysis showed colocalization of OCTN1 with the NPC marker nestin in cultured NPCs and mouse embryonic carcinoma P19 cells differentiated into neural progenitor-like cells (P19-NPCs). These cells exhibited time-dependent [3H]ERGO uptake. These results demonstrate that OCTN1 is functionally expressed in murine NPCs. Cultured NPCs and P19-NPCs formed neurospheres from clusters of proliferating cells in a culture time-dependent manner. Exposure of cultured NPCs to ERGO or other antioxidants (edaravone and ascorbic acid) led to a significant decrease in the area of neurospheres with concomitant elimination of intracellular reactive oxygen species. Transfection of P19-NPCs with small interfering RNA for OCTN1 markedly promoted formation of neurospheres with a concomitant decrease of [3H]ERGO uptake. On the other hand, exposure of cultured NPCs to ERGO markedly increased the number of cells immunoreactive for the neuronal marker βIII-tubulin, but decreased the number immunoreactive for the astroglial marker glial fibrillary acidic protein (GFAP), with concomitant up-regulation of neuronal differentiation activator gene Math1. Interestingly, edaravone and ascorbic acid did not affect such differentiation of NPCs, in contrast to the case of proliferation. Knockdown of OCTN1 increased the number of cells immunoreactive for GFAP, but decreased the number immunoreactive for βIII-tubulin, with concomitant down-regulation of Math1 in P19-NPCs. Thus, OCTN1-mediated uptake of ERGO in NPCs inhibits cellular proliferation via regulation of oxidative stress, and also promotes cellular differentiation by modulating the expression of basic helix-loop-helix transcription factors via an unidentified mechanism different from antioxidant action.
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Affiliation(s)
- Takahiro Ishimoto
- Faculty of Pharmacy, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Noritaka Nakamichi
- Faculty of Pharmacy, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Hiroshi Hosotani
- Faculty of Pharmacy, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Yusuke Masuo
- Faculty of Pharmacy, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Tomoko Sugiura
- Faculty of Pharmacy, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Yukio Kato
- Faculty of Pharmacy, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan
- * E-mail:
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41
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SLC22A13 catalyses unidirectional efflux of aspartate and glutamate at the basolateral membrane of type A intercalated cells in the renal collecting duct. Biochem J 2013; 457:243-51. [DOI: 10.1042/bj20130654] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
SLC22A13 is specifically expressed in renal type A intercalated cells where it mediates the basolateral expulsion of aspartate and glutamate.
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Toh DSL, Cheung FSG, Murray M, Pern TK, Lee EJD, Zhou F. Functional Analysis of Novel Variants in the Organic Cation/Ergothioneine Transporter 1 Identified in Singapore Populations. Mol Pharm 2013; 10:2509-16. [DOI: 10.1021/mp400193r] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Dorothy Su Lin Toh
- Faculty of Pharmacy, University of Sydney, NSW 2006, Australia
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119245
| | | | - Michael Murray
- Faculty of Pharmacy, University of Sydney, NSW 2006, Australia
- Discipline of Pharmacology, School
of Medical Sciences, The University of Sydney, NSW 2006, Australia
| | - Tan Kuan Pern
- Bioinformatics Institute, Agency for Science, Technology and Research (A*STAR), Singapore 138632
| | - Edmund Jon Deoon Lee
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119245
| | - Fanfan Zhou
- Faculty of Pharmacy, University of Sydney, NSW 2006, Australia
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Nakamichi N, Shima H, Asano S, Ishimoto T, Sugiura T, Matsubara K, Kusuhara H, Sugiyama Y, Sai Y, Miyamoto KI, Tsuji A, Kato Y. Involvement of carnitine/organic cation transporter OCTN1/SLC22A4 in gastrointestinal absorption of metformin. J Pharm Sci 2013; 102:3407-17. [PMID: 23666872 DOI: 10.1002/jps.23595] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2012] [Revised: 04/16/2013] [Accepted: 04/18/2013] [Indexed: 11/11/2022]
Abstract
Metformin is a widely used oral anti-diabetic, but the molecular mechanism(s) of its gastrointestinal membrane permeation remains unclear. Here, we examined the role of carnitine/organic cation transporter OCTN1/SLC22A4, which is localized on apical membranes of small intestine in mice and humans, in metformin absorption. The maximum plasma concentration (Cmax ) after oral administration of metformin (50 mg/kg) in octn1 gene knockout mice (octn1 (-/-) ) was higher than that in wild-type mice, with only a minimal difference in terminal half-life, but Cmax in octn1(-/-) mice given a higher dose (175 mg/kg) was lower than that in wild-type mice. Systemic elimination of metformin after intravenous administration was similar in the two strains, suggesting the possible involvement of OCTN1 in the gastrointestinal absorption. OCTN1-mediated uptake of metformin was observed in human embryonic kidney 293 cells transfected with mouse OCTN1 gene, but much lower than the uptake of the typical substrate [(3) H]ergothioneine (ERGO). In particular, the distribution volume for OCTN1-mediated uptake increased markedly and then tended to decrease as the metformin concentration was increased. Efflux of metformin preloaded in intestinal epithelial cell line Caco-2 was inhibited by ERGO. Overall, the present findings suggest that OCTN1 transports metformin and may be involved in its oral absorption in small intestine.
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Affiliation(s)
- Noritaka Nakamichi
- Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa 920-1192, Japan
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Macdonald C, Shao D, Oli A, Agu RU. Characterization of Calu-3 cell monolayers as a model of bronchial epithelial transport: organic cation interaction studies. J Drug Target 2012; 21:97-106. [PMID: 23050869 DOI: 10.3109/1061186x.2012.731068] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND To fully exploit organic cation transporters for targeted drug delivery in the lung, the use of a readily available and well-characterized tissue culture model and cheap easily detectable substrates is indispensable. OBJECTIVES To investigate the suitability of Calu-3 as tissue model for characterizing organic cation permeation across the bronchial cells using a fluorescent dye, 4-(4-(Dimethylamino)styryl)-N-methylpyridinium iodide (4-DI-1-ASP). METHODS Substrate uptake, inhibition, and transport were performed to establish active transport mechanism. Organic cation transporter expression was determined with quantitative polymerase chain reaction (qPCR), immune-histochemistry, and fluorescent microscopy. RESULTS 4-Di-1-ASP uptake in Calu-3 cells was concentration (K(m) = 2.7 ± 0.3 mM, V(max) = 4.6 ± 2.6 nmol/µg protein/30 min), temperature (uptake at 37°C>>4°C), and pH dependent (higher uptake at pH ≥ 7). L-carnitine, verapamil, and corticosterone significantly inhibited its uptake with IC(50) of 28.2, 0.81, and 0.12 mM, respectively. Transport of the dye across the cells was polarized (AP→BL transport was 2.5-fold > BL→AP), saturable (Km = 43.9 ± 3.2) (µM; Vmax =0.0228 ± nmol/cm(2)/sec) and reduced 3-fold by metabolic inhibition. The expression pattern of the organic cation transporters (OCT) and carnitine/organic cation transporter (OCTN) isoforms was: OCT1<<OCT3 <OCTN1<OCTN2; OCT2 was not detected. CONCLUSIONS Based on qPCR, immunohistochemistry, uptake and transport data, the Calu-3 cells can be used as a model for not only studying strategies for optimizing the effect of inhaled organic cations, but also for cross-validating newly-developed respiratory cell lines.
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Affiliation(s)
- Chris Macdonald
- Biopharmaceutics and Drug Delivery Laboratory, Dalhousie University, Halifax, NS, Canada
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45
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Mitochondria-targeted antioxidants and metabolic modulators as pharmacological interventions to slow ageing. Biotechnol Adv 2012; 31:563-92. [PMID: 23022622 DOI: 10.1016/j.biotechadv.2012.09.005] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 09/19/2012] [Accepted: 09/21/2012] [Indexed: 02/07/2023]
Abstract
Populations in many nations today are rapidly ageing. This unprecedented demographic change represents one of the main challenges of our time. A defining property of the ageing process is a marked increase in the risk of mortality and morbidity with age. The incidence of cancer, cardiovascular and neurodegenerative diseases increases non-linearly, sometimes exponentially with age. One of the most important tasks in biogerontology is to develop interventions leading to an increase in healthy lifespan (health span), and a better understanding of basic mechanisms underlying the ageing process itself may lead to interventions able to delay or prevent many or even all age-dependent conditions. One of the putative basic mechanisms of ageing is age-dependent mitochondrial deterioration, closely associated with damage mediated by reactive oxygen species (ROS). Given the central role that mitochondria and mitochondrial dysfunction play not only in ageing but also in apoptosis, cancer, neurodegeneration and other age-related diseases there is great interest in approaches to protect mitochondria from ROS-mediated damage. In this review, we explore strategies of targeting mitochondria to reduce mitochondrial oxidative damage with the aim of preventing or delaying age-dependent decline in mitochondrial function and some of the resulting pathologies. We discuss mitochondria-targeted and -localized antioxidants (e.g.: MitoQ, SkQ, ergothioneine), mitochondrial metabolic modulators (e.g. dichloroacetic acid), and uncouplers (e.g.: uncoupling proteins, dinitrophenol) as well as some alternative future approaches for targeting compounds to the mitochondria, including advances from nanotechnology.
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46
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The ergothioneine transporter controls and indicates ergothioneine activity--a review. Prev Med 2012; 54 Suppl:S71-4. [PMID: 22182480 DOI: 10.1016/j.ypmed.2011.12.001] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 11/29/2011] [Accepted: 12/05/2011] [Indexed: 12/19/2022]
Abstract
Ergothioneine (ET) is a natural compound which humans and other vertebrates cannot synthesize themselves; it must be absorbed from food in which it is distributed very unevenly. In general, ET is considered an intracellular antioxidant. However, the precise physiological purpose of ET and the consequences of ET deficiency are still unclear. The ergothioneine transporter ETT (old name OCTN1; human gene symbol SLC22A4) is a powerful and highly specific transporter for the uptake of ET. Cells lacking ETT do not accumulate ET, since the plasma membrane is virtually impermeable for this hydrophilic zwitterion compound. The existence of an evolutionary conserved ergothioneine transporter implies a beneficial role for ET. ETT is the first and so far only biomarker of ET activity. Only cells with strong expression of ETT can accumulate ET to high levels. In the human body, the ability to absorb, distribute, and retain ET depends entirely on this transporter. Blockade or inactivation of ETT in animal models may be essential to at last understand the function of ET. In this review of ETT, the focus is on substrate specificity, subcellular localization, human expression profile and expression profiles across species.
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Cheah IK, Halliwell B. Ergothioneine; antioxidant potential, physiological function and role in disease. Biochim Biophys Acta Mol Basis Dis 2011; 1822:784-93. [PMID: 22001064 DOI: 10.1016/j.bbadis.2011.09.017] [Citation(s) in RCA: 274] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Accepted: 09/29/2011] [Indexed: 01/09/2023]
Abstract
Since its discovery, the unique properties of the naturally occurring amino acid, L-ergothioneine (EGT; 2-mercaptohistidine trimethylbetaine), have intrigued researchers for more than a century. This widely distributed thione is only known to be synthesized by non-yeast fungi, mycobacteria and cyanobacteria but accumulates in higher organisms at up to millimolar levels via an organic cation transporter (OCTN1). The physiological role of EGT has yet to be established. Numerous in vitro assays have demonstrated the antioxidant and cytoprotective capabilities of EGT against a wide range of cellular stressors, but an antioxidant role has yet to be fully verified in vivo. Nevertheless the accumulation, tissue distribution and scavenging properties, all highlight the potential for EGT to function as a physiological antioxidant. This article reviews our current state of knowledge. This article is part of a Special Issue entitled: Antioxidants and Antioxidant Treatment in Disease.
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Affiliation(s)
- Irwin K Cheah
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 28 Medical Drive, Singapore
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Abstract
OAT (organic anion transporter) 2 [human gene symbol SLC22A7 (SLC is solute carrier)] is a member of the SLC22 family of transport proteins. In the rat, the principal site of expression of OAT2 is the sinusoidal membrane domain of hepatocytes. The particular physiological function of OAT2 in liver has been unresolved so far. In the present paper, we have used the strategy of LC (liquid chromatography)-MS difference shading to search for specific and cross-species substrates of OAT2. Heterologous expression of human and rat OAT2 in HEK (human embryonic kidney)-293 cells stimulated accumulation of the zwitterion trigonelline; subsequently, orotic acid was identified as an excellent and specific substrate of OAT2 from the rat (clearance=106 μl·min⁻¹·mg of protein⁻¹) and human (46 μl·min⁻¹·mg of protein⁻¹). The force driving uptake of orotic acid was identified as glutamate antiport. Efficient transport of glutamate by OAT2 was directly demonstrated by uptake of [³H]glutamate. However, because of high intracellular glutamate, OAT2 operates as glutamate efflux transporter. Thus expression of OAT2 markedly increased the release of glutamate (measured by LC-MS) from cells, even without extracellular exchange substrate. Orotic acid strongly trans-stimulated efflux of glutamate. We thus propose that OAT2 physiologically functions as glutamate efflux transporter. OAT2 mRNA was detected, after laser capture microdissection of rat liver slices, equally in periportal and pericentral regions; previous reports of hepatic release of glutamate into blood can now be explained by OAT2 activity. A specific OAT2 inhibitor could, by lowering plasma glutamate and thus promoting brain-to-blood efflux of glutamate, alleviate glutamate exotoxicity in acute brain conditions.
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50
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Schauss AG, Vértesi A, Endres JR, Hirka G, Clewell A, Qureshi I, Pasics I. Evaluation of the safety of the dietary antioxidant ergothioneine using the bacterial reverse mutation assay. Toxicology 2010; 278:39-45. [DOI: 10.1016/j.tox.2010.07.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Accepted: 07/22/2010] [Indexed: 11/16/2022]
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