1
|
Funck D, Sinn M, Forlani G, Hartig JS. Guanidine production by plant homoarginine-6-hydroxylases. eLife 2024; 12:RP91458. [PMID: 38619227 PMCID: PMC11018352 DOI: 10.7554/elife.91458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2024] Open
Abstract
Metabolism and biological functions of the nitrogen-rich compound guanidine have long been neglected. The discovery of four classes of guanidine-sensing riboswitches and two pathways for guanidine degradation in bacteria hint at widespread sources of unconjugated guanidine in nature. So far, only three enzymes from a narrow range of bacteria and fungi have been shown to produce guanidine, with the ethylene-forming enzyme (EFE) as the most prominent example. Here, we show that a related class of Fe2+- and 2-oxoglutarate-dependent dioxygenases (2-ODD-C23) highly conserved among plants and algae catalyze the hydroxylation of homoarginine at the C6-position. Spontaneous decay of 6-hydroxyhomoarginine yields guanidine and 2-aminoadipate-6-semialdehyde. The latter can be reduced to pipecolate by pyrroline-5-carboxylate reductase but more likely is oxidized to aminoadipate by aldehyde dehydrogenase ALDH7B in vivo. Arabidopsis has three 2-ODD-C23 isoforms, among which Din11 is unusual because it also accepted arginine as substrate, which was not the case for the other 2-ODD-C23 isoforms from Arabidopsis or other plants. In contrast to EFE, none of the three Arabidopsis enzymes produced ethylene. Guanidine contents were typically between 10 and 20 nmol*(g fresh weight)-1 in Arabidopsis but increased to 100 or 300 nmol*(g fresh weight)-1 after homoarginine feeding or treatment with Din11-inducing methyljasmonate, respectively. In 2-ODD-C23 triple mutants, the guanidine content was strongly reduced, whereas it increased in overexpression plants. We discuss the implications of the finding of widespread guanidine-producing enzymes in photosynthetic eukaryotes as a so far underestimated branch of the bio-geochemical nitrogen cycle and propose possible functions of natural guanidine production.
Collapse
Affiliation(s)
- Dietmar Funck
- Department of Chemistry, University of KonstanzKonstanzGermany
| | - Malte Sinn
- Department of Chemistry, University of KonstanzKonstanzGermany
| | - Giuseppe Forlani
- Department of Life Science and Biotechnology, University of FerraraFerraraItaly
| | - Jörg S Hartig
- Department of Chemistry, University of KonstanzKonstanzGermany
| |
Collapse
|
2
|
Wang S, Chen X, Liu Z, Yu S, Fu J, Zeng X. Rhodamine-based Fluorescent Probe With Quick Response and High Selectivity for Imaging Labile Ferrous Iron in Living Cells and Zebrafish. J Fluoresc 2023:10.1007/s10895-023-03551-2. [PMID: 38157085 DOI: 10.1007/s10895-023-03551-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Accepted: 12/12/2023] [Indexed: 01/03/2024]
Abstract
The transition between its various oxidation states of Iron plays a crucial part in various chemical transformation of cells. Misregulation of iron can give rise to the iron-catalyzed reactive oxygen species disorder which have been linked to a variety of diseases, so it is crucial to monitor the labile iron pool in vivo for clinical diagnosis. According to iron autoxidation and hydrogen abstraction reaction, we reported a novel "off-on" fluorescent probe to response to ferrous (Fe2+) both in solutions and biological systems. The probe responds to Fe2+ with good selectivity toward competing metal ions. What's more, the probe presents significant fluorescent enhancement to Fe2+ in less than 1 min, making real-time sensing in biological system possible. The applications of the probe in bioimaging revealed the changes in labile iron pool by iron autoxidation or diverse stimuli.
Collapse
Affiliation(s)
- Shanshan Wang
- Center of Characterization and Analysis, Jilin Institute of Chemical Technology, Jilin, People's Republic of China
| | - Xin Chen
- School of Chemical and Pharmaceutical Engineering, Jilin Institute of Chemical Technology, Jilin, People's Republic of China
| | - Zhigang Liu
- Center of Characterization and Analysis, Jilin Institute of Chemical Technology, Jilin, People's Republic of China
| | - Shihua Yu
- School of Chemical and Pharmaceutical Engineering, Jilin Institute of Chemical Technology, Jilin, People's Republic of China
| | - Jing Fu
- Jinan Stomatol Hosp, Periodont & Oral Med Dept, Jinan, Shandong, People's Republic of China.
| | - Xiaodan Zeng
- Center of Characterization and Analysis, Jilin Institute of Chemical Technology, Jilin, People's Republic of China.
| |
Collapse
|
3
|
Liu R, Yang J, Li Y, Xie J, Wang J. Heme oxygenase-1: The roles of both good and evil in neurodegenerative diseases. J Neurochem 2023; 167:347-361. [PMID: 37746863 DOI: 10.1111/jnc.15969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 09/12/2023] [Accepted: 09/12/2023] [Indexed: 09/26/2023]
Abstract
Heme oxygenase-1 (HO-1) is the only way for cells to decompose heme. It can cleave heme to produce carbon monoxide (CO), ferrous iron (Fe2+ ), and biliverdin (BV). BV is reduced to bilirubin (BR) by biliverdin reductase(BVR). In previous studies, HO-1 was considered to have protective effects because of its anti-inflammatory, anti-apoptosis, and antiproliferation functions. However, emerging experimental studies have found that the metabolites derived from HO-1 can cause increase iin intracellular oxidative stress, mitochondrial damage, iron death, and autophagy. Because of its particularity, it is very meaningful to understand its exact mechanism. In this review, we summarized the protective and toxic effects of HO-1, its potential mechanism, its role in neurodegenerative diseases and related drug research. This knowledge may be beneficial to the development of new therapies for neurodegenerative diseases and is crucial to the development of new therapeutic strategies and biomarkers.
Collapse
Affiliation(s)
- Rong Liu
- School of Basic Medicine, Qingdao University, Qingdao, China
- Institute of Brain Science and Disease, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, China
| | - Jiahua Yang
- School of Basic Medicine, Qingdao University, Qingdao, China
- Institute of Brain Science and Disease, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, China
| | - Yinghui Li
- School of Basic Medicine, Qingdao University, Qingdao, China
- Institute of Brain Science and Disease, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, China
| | - Junxia Xie
- Institute of Brain Science and Disease, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, China
| | - Jun Wang
- School of Basic Medicine, Qingdao University, Qingdao, China
- Institute of Brain Science and Disease, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Qingdao University, Qingdao, China
| |
Collapse
|
4
|
Suo SN, Tian Y, Tan WL, Lou XY, Xu H, Wang YW, Peng Y. A Near-Infrared Colorimetric Fluorescent Probe for Ferrous Ion Detection and Imaging. J Fluoresc 2023:10.1007/s10895-023-03354-5. [PMID: 37505364 DOI: 10.1007/s10895-023-03354-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 07/18/2023] [Indexed: 07/29/2023]
Abstract
Based on the N-redox mechanism, a turn-on near-infrared fluorescence probe (SWJT-15) with cyano isophorone as skeleton was designed and synthesized for the detection of ferrous ions (Fe2+). The probe has a lower detection limit (83 nM) and fast response (200 s) to Fe2+ ions. And the probe has unique selectivity and good anti-interference performance against Fe2+ ions compared to other metal ions. Moreover, the probe has been successfully applied to imaging Fe2+ ions in HeLa cells.
Collapse
Affiliation(s)
- Sheng-Nan Suo
- School of Life Science and Engineering, School of Chemistry, Southwest Jiaotong University, Chengdu, 610031, People's Republic of China
| | - Yang Tian
- School of Life Science and Engineering, School of Chemistry, Southwest Jiaotong University, Chengdu, 610031, People's Republic of China
| | - Wei-Lun Tan
- School of Life Science and Engineering, School of Chemistry, Southwest Jiaotong University, Chengdu, 610031, People's Republic of China
| | - Xiao-Yang Lou
- School of Life Science and Engineering, School of Chemistry, Southwest Jiaotong University, Chengdu, 610031, People's Republic of China
| | - Hai Xu
- School of Life Science and Engineering, School of Chemistry, Southwest Jiaotong University, Chengdu, 610031, People's Republic of China.
| | - Ya-Wen Wang
- School of Life Science and Engineering, School of Chemistry, Southwest Jiaotong University, Chengdu, 610031, People's Republic of China.
| | - Yu Peng
- School of Life Science and Engineering, School of Chemistry, Southwest Jiaotong University, Chengdu, 610031, People's Republic of China
| |
Collapse
|
5
|
Zhang K, Wu Y, Chen G, Wang H, Liu Y, Zhou Y. Heat shock protein 27 deficiency promotes ferrous ion absorption and enhances acyl-Coenzyme A synthetase long-chain family member 4 stability to promote glioblastoma cell ferroptosis. Cancer Cell Int 2023; 23:5. [PMID: 36639654 PMCID: PMC9840324 DOI: 10.1186/s12935-023-02848-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 01/02/2023] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Glioblastoma is one of the malignant tumors of the central nervous system with high lethality, high disability and low survival rate. Effective induction of its death is one of the existing challenges. In recent studies, heat shock protein 27 (HSP27) has been shown to be associated with ferroptosis; therefore, targeting HSP27 may be a potential therapeutic approach for GBM. METHODS Immunohistochemistry and western blot analysis were used to detect the expression of HSP27 in GBM tissues. CCK8, plate clone formation assay, EdU proliferation assay for cell proliferation ability, PI, LDH release assay for cell viability. Reactive oxygen, iron levels, and mitochondrial potential for HSP27 silencing were assayed for ferrotosis in vitro. Western blotting and IP were used to verify the relationship between HSP27 and ACSL4. The effect of knockdown of HSP27 on tumor growth capacity was assessed in an intracranial xenograft model. RESULTS HSP27 was significantly highly expressed in GBM. In vitro experiments, knockdown of HSP27 significantly induced ferroptosis in GBM cells. IP and western blot demonstrated a sumo-ization link between HSP27 and ACSL4. In vivo experiments, HSP27 deficiency retarded tumor growth rate by promoting ferroptosis. CONCLUSIONS HSP27 deficiency promotes GBM ferroptosis. Targeting HSP27 may serve as a new direction for GBM treatment.
Collapse
Affiliation(s)
- Kai Zhang
- grid.429222.d0000 0004 1798 0228Department of Neurosurgery, Laboratory of Brain and Nerve Research, The First Affiliated Hospital of Soochow University, Suzhou, 215006 Jiangsu China
| | - Yue Wu
- grid.429222.d0000 0004 1798 0228Department of Neurosurgery, Laboratory of Brain and Nerve Research, The First Affiliated Hospital of Soochow University, Suzhou, 215006 Jiangsu China
| | - Guangliang Chen
- grid.429222.d0000 0004 1798 0228Department of Neurosurgery, Laboratory of Brain and Nerve Research, The First Affiliated Hospital of Soochow University, Suzhou, 215006 Jiangsu China
| | - Hao Wang
- grid.429222.d0000 0004 1798 0228Department of Neurosurgery, Laboratory of Brain and Nerve Research, The First Affiliated Hospital of Soochow University, Suzhou, 215006 Jiangsu China
| | - Yongsheng Liu
- grid.429222.d0000 0004 1798 0228Department of Neurosurgery, Laboratory of Brain and Nerve Research, The First Affiliated Hospital of Soochow University, Suzhou, 215006 Jiangsu China
| | - Youxin Zhou
- grid.429222.d0000 0004 1798 0228Department of Neurosurgery, Laboratory of Brain and Nerve Research, The First Affiliated Hospital of Soochow University, Suzhou, 215006 Jiangsu China
| |
Collapse
|
6
|
Wang H, Fu T, Ai M, Liu J. Ratiometric fluorescence nanoprobe based on carbon dots and terephthalic acid for determining Fe 2+ in environmental samples. Anal Bioanal Chem 2022; 414:6735-6741. [PMID: 35864267 DOI: 10.1007/s00216-022-04233-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 06/25/2022] [Accepted: 07/14/2022] [Indexed: 11/24/2022]
Abstract
A ratiometric fluorescent nanoprobe using carbon dots (CDs) and involving oxidation of terephthalic acid (TPA) induced by hydroxyl radicals (·OH) was developed for sensitively and selectively determining Fe2+ ions. When Fe2+ ions are added to the TPA@CDs/H2O2 system, ·OH produced through the Fenton reaction oxidizes the non-fluorescent TPA to give 2-hydroxyl terephthalic acid, which fluoresces at 423 nm when excited at 286 nm. The ·OH and Fe3+ produced quench CD fluorescence at 326 nm. The 2-hydroxyl terephthalic acid to CD fluorescence intensity ratio linearly increased as the Fe2+ concentration increased in the range 0.5-50 μM, and the detection limit was 0.25 μM. The new assay is very selective because it involves dual-emission reverse change ratio fluorescence sensing, which can exclude matrix effects. The new nanoprobe was used to determine Fe2+ concentrations in real water samples, and the recoveries were found to be acceptable. Schematic of the ratiometric fluorometric method for determining Fe2+ based on CDs and TPA.
Collapse
Affiliation(s)
- Huaxin Wang
- College of Chemistry and Materials Science, The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, Anhui Normal University, Wuhu, 241000, China
| | - Ting Fu
- College of Chemistry and Materials Science, The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, Anhui Normal University, Wuhu, 241000, China
| | - Mimi Ai
- College of Chemistry and Materials Science, The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, Anhui Normal University, Wuhu, 241000, China
| | - Jinshui Liu
- College of Chemistry and Materials Science, The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, Anhui Normal University, Wuhu, 241000, China.
| |
Collapse
|
7
|
Zheng XW, Qin JF, Wang XJ, Chen HC, Zhu ZJ, Chen ZG. [Promoting Nitrogen Removal in ANAMMOX Biofilm Reactor by Fe 2+ Under Low Nitrogen Concentration]. Huan Jing Ke Xue 2022; 43:2047-2054. [PMID: 35393828 DOI: 10.13227/j.hjkx.202107071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The feasibility for nitrogen removal in a two-stage ANAMMOX biofilm reactor promoted by Fe2+ under low nitrogen concentration was investigated. The results showed that the ANAMMOX reaction could be effectively promoted by a ρ(Fe2+) of 5, 10, and 15 mg·L-1. A ρ(Fe2+) of 10 mg·L-1 presented the highest promotion for the ANAMMOX reaction, with the highest nitrogen removal efficiency (NRE) of 81.71% under a ρ(TN) of 150 mg·L-1and a nitrogen loading rate (NLR) of 0.62 kg·(m3·d)-1. Fe2+ promoted the secretion of extracellular polymeric substance (EPS) and the synthesis of heme c in the ANAMMOX system. Batch test results further verified the positive effects by Fe2+on the activity of anaerobic ammonium oxidizing bacteria (AnAOB). The specific ANAMMOX activity (SAA) of 10 mg·L-1 ρ(Fe2+) was 3.6 times as high as that of the control group[ρ(Fe2+)=0 mg·L-1], whereas the activity of AnAOB was significantly inhibited with ρ(Fe2+) increased to 20 mg·L-1. High-throughput sequencing results showed that the addition of Fe2+ increased the abundance of Candidatus_Kuenenia. When ρ(Fe2+) was 10 mg·L-1, the relative abundance of Candidatus_Kuenenia in reactor 1 and reactor 2 increased to 16.18% and 4.22%, respectively. The stable operation of the two-stage ANAMMOX biofilm process promoted by Fe2+provides an alternative technology for low-strength nitrogen wastewater.
Collapse
Affiliation(s)
- Xu-Wen Zheng
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
- Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Cluster, Ministry of Education, Guangzhou 510006, China
| | - Jia-Fu Qin
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
- Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Cluster, Ministry of Education, Guangzhou 510006, China
| | - Xiao-Jun Wang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
- Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Cluster, Ministry of Education, Guangzhou 510006, China
- Hua An Biotech Co., Ltd., Foshan 528300, China
| | - Hao-Chuan Chen
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
- Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Cluster, Ministry of Education, Guangzhou 510006, China
| | - Zi-Jian Zhu
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
- Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Cluster, Ministry of Education, Guangzhou 510006, China
| | - Zhen-Guo Chen
- Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Cluster, Ministry of Education, Guangzhou 510006, China
- Hua An Biotech Co., Ltd., Foshan 528300, China
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641, China
| |
Collapse
|
8
|
Quintana J, Bernal M, Scholle M, Holländer-Czytko H, Nguyen NT, Piotrowski M, Mendoza-Cózatl DG, Haydon MJ, Krämer U. Root-to-shoot iron partitioning in Arabidopsis requires IRON-REGULATED TRANSPORTER1 (IRT1) protein but not its iron(II) transport function. Plant J 2022; 109:992-1013. [PMID: 34839543 DOI: 10.1111/tpj.15611] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 11/11/2021] [Accepted: 11/15/2021] [Indexed: 05/26/2023]
Abstract
IRON-REGULATED TRANSPORTER1 (IRT1) is the root high-affinity ferrous iron (Fe) uptake system and indispensable for the completion of the life cycle of Arabidopsis thaliana without vigorous Fe supplementation. Here we provide evidence supporting a second role of IRT1 in root-to-shoot partitioning of Fe. We show that irt1 mutants overaccumulate Fe in roots, most prominently in the cortex of the differentiation zone in irt1-2, compared to the wild type. Shoots of irt1-2 are severely Fe-deficient according to Fe content and marker transcripts, as expected. We generated irt1-2 lines producing IRT1 mutant variants carrying single amino-acid substitutions of key residues in transmembrane helices IV and V, Ser206 and His232, which are required for transport activity in yeast. Root short-term 55 Fe uptake rates were uninformative concerning IRT1-mediated transport. Overall irt1-like concentrations of the secondary substrate Mn suggested that the transgenic Arabidopsis lines also remain incapable of IRT1-mediated root Fe uptake. Yet, IRT1S206A partially complements rosette dwarfing and leaf chlorosis of irt1-2, as well as root-to-shoot Fe partitioning and gene expression defects of irt1-2, all of which are fully complemented by wild-type IRT1. Taken together, these results suggest a regulatory function for IRT1 in root-to-shoot Fe partitioning that does not require Fe transport activity of IRT1. Among the genes of which transcript levels are partially dependent on IRT1, we identify MYB DOMAIN PROTEIN10, MYB DOMAIN PROTEIN72 and NICOTIANAMINE SYNTHASE4 as candidates for effecting IRT1-dependent Fe mobilization in roots. Understanding the biological functions of IRT1 will help to improve Fe nutrition and the nutritional quality of agricultural crops.
Collapse
Affiliation(s)
- Julia Quintana
- Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801, Bochum, Germany
| | - María Bernal
- Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801, Bochum, Germany
- Department of Plant Nutrition, Estación Experimental de Aula Dei-CSIC, 50059, Zaragoza, Spain
| | - Marleen Scholle
- Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801, Bochum, Germany
| | | | - Nga T Nguyen
- Division of Plant Sciences, MU-Columbia, Columbia, MO, 65211-7310, USA
| | - Markus Piotrowski
- Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801, Bochum, Germany
| | | | - Michael J Haydon
- Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801, Bochum, Germany
| | - Ute Krämer
- Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801, Bochum, Germany
| |
Collapse
|
9
|
Quintana J, Bernal M, Scholle M, Holländer-Czytko H, Nguyen NT, Piotrowski M, Mendoza-Cózatl DG, Haydon MJ, Krämer U. Root-to-shoot iron partitioning in Arabidopsis requires IRON-REGULATED TRANSPORTER1 (IRT1) protein but not its iron(II) transport function. Plant J 2022; 109:992-1013. [PMID: 34839543 DOI: 10.1101/2021.02.08.430285] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 11/11/2021] [Accepted: 11/15/2021] [Indexed: 05/29/2023]
Abstract
IRON-REGULATED TRANSPORTER1 (IRT1) is the root high-affinity ferrous iron (Fe) uptake system and indispensable for the completion of the life cycle of Arabidopsis thaliana without vigorous Fe supplementation. Here we provide evidence supporting a second role of IRT1 in root-to-shoot partitioning of Fe. We show that irt1 mutants overaccumulate Fe in roots, most prominently in the cortex of the differentiation zone in irt1-2, compared to the wild type. Shoots of irt1-2 are severely Fe-deficient according to Fe content and marker transcripts, as expected. We generated irt1-2 lines producing IRT1 mutant variants carrying single amino-acid substitutions of key residues in transmembrane helices IV and V, Ser206 and His232, which are required for transport activity in yeast. Root short-term 55 Fe uptake rates were uninformative concerning IRT1-mediated transport. Overall irt1-like concentrations of the secondary substrate Mn suggested that the transgenic Arabidopsis lines also remain incapable of IRT1-mediated root Fe uptake. Yet, IRT1S206A partially complements rosette dwarfing and leaf chlorosis of irt1-2, as well as root-to-shoot Fe partitioning and gene expression defects of irt1-2, all of which are fully complemented by wild-type IRT1. Taken together, these results suggest a regulatory function for IRT1 in root-to-shoot Fe partitioning that does not require Fe transport activity of IRT1. Among the genes of which transcript levels are partially dependent on IRT1, we identify MYB DOMAIN PROTEIN10, MYB DOMAIN PROTEIN72 and NICOTIANAMINE SYNTHASE4 as candidates for effecting IRT1-dependent Fe mobilization in roots. Understanding the biological functions of IRT1 will help to improve Fe nutrition and the nutritional quality of agricultural crops.
Collapse
Affiliation(s)
- Julia Quintana
- Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801, Bochum, Germany
| | - María Bernal
- Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801, Bochum, Germany
- Department of Plant Nutrition, Estación Experimental de Aula Dei-CSIC, 50059, Zaragoza, Spain
| | - Marleen Scholle
- Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801, Bochum, Germany
| | | | - Nga T Nguyen
- Division of Plant Sciences, MU-Columbia, Columbia, MO, 65211-7310, USA
| | - Markus Piotrowski
- Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801, Bochum, Germany
| | | | - Michael J Haydon
- Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801, Bochum, Germany
| | - Ute Krämer
- Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801, Bochum, Germany
| |
Collapse
|
10
|
Zhang Q, Qu Y, Zhang Q, Li F, Li B, Li Z, Dong Y, Lu L, Cai X. Exosomes derived from hepatitis B virus-infected hepatocytes promote liver fibrosis via miR-222/TFRC axis. Cell Biol Toxicol 2022:10.1007/s10565-021-09684-z. [PMID: 34978008 DOI: 10.1007/s10565-021-09684-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 11/18/2021] [Indexed: 11/02/2022]
Abstract
Exosomal miRNAs activates hepatic stellate cell (HSC) and promote fibrosis. miR-222 was found to be increased in hepatitis B virus (HBV)-infected hepatocytes, and ferroptosis was reported to ameliorate liver fibrosis (LF). Although miR-222 and ferroptosis have been implicated in LF, the association between miR-222 and ferroptosis and how they coordinate to regulate LF are still not explicit. This study investigates the roles of miR-222 and transferrin receptor (TFRC) in LF. Lipid reactive oxygen species (ROS) level was analyzed by flow cytometry. FerroOrange staining was used to measure intracellular iron level. Luciferase reporter assay was adopted to confirm the binding of miR-222 and TFRC. Real-time quantitative PCR and immunoblots were applied to analyze gene and protein expression. The results showed that supplementation of exosomes derived from HBV-infected LO2 cells remarkably enhanced LX-2 cell activation, evidenced by elevated hydroxyprolin (Hyp) secretion and α-SMA and COL1A2 expression. miR-222 was significantly increased in HBV-Exo. Overexpressing miR-222 upregulated cell viability, secretion of Hpy, and expression of α-SMA and COL1A2, which were all blocked by overexpression of TFRC. Further study showed that TFRC was a target of miR-222, and miR-222 promoted LX-2 cell activation through suppressing TFRC-induced ferroptosis in LX-2 cells. Exosomal miR-222 derived from HBV-infected hepatocytes promoted LF through inhibiting TFRC and TFRC-induced ferroptosis. This study emphasizes the significance of miR-222/TFRC axis in LF and suggests new insights in clinical decision making while treating LF. Exosomes derived from HBV-infected LO2 cells promote LX-2 cell activation and liver fibrosis in mouse Exosomal miR-222 derived from HBV-infected LO2 cells promotes LX-2 cell activation TFRC is a target of miR-222 and inhibits LX-2 cell activation induced by miR-222 miR-222 promotes LX-2 cell activation through inhibiting TFRC-induced ferroptosis.
Collapse
Affiliation(s)
- Qidi Zhang
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, No. 650 New Songjiang Road, Shanghai, 201620, China
| | - Ying Qu
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, No. 650 New Songjiang Road, Shanghai, 201620, China
| | - Qingqing Zhang
- Department of Gastroenterology, Ruian People's Hospital, No. 108 Wansong Road, Ruian, 325200, China
| | - Fei Li
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, No. 650 New Songjiang Road, Shanghai, 201620, China
| | - Binghang Li
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, No. 650 New Songjiang Road, Shanghai, 201620, China
| | - Zhenghong Li
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, No. 650 New Songjiang Road, Shanghai, 201620, China
| | - Yuwei Dong
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, No. 650 New Songjiang Road, Shanghai, 201620, China
| | - Lungen Lu
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, No. 650 New Songjiang Road, Shanghai, 201620, China.
| | - Xiaobo Cai
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, No. 650 New Songjiang Road, Shanghai, 201620, China.
| |
Collapse
|
11
|
Türkoğlu Demirkol G, Çelik SÖ, Güneş Durak S, Acarer S, Çetin E, Akarçay Demir S, Tüfekci N. Effects of Fe(OH) 3 and MnO 2 Flocs on Iron/Manganese Removal and Fouling in Aerated Submerged Membrane Systems. Polymers (Basel) 2021; 13:polym13193201. [PMID: 34641017 PMCID: PMC8512643 DOI: 10.3390/polym13193201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/27/2021] [Accepted: 08/30/2021] [Indexed: 01/25/2023] Open
Abstract
Many treatment methods are used to remove iron and manganese from water. Aeration and membrane filtration are two of these methods. In this study, Fe2+ and Mn2+ removal by aeration with different catalysts and instead of simple membrane filtration applied in other studies, the aerated-submerged membrane systems were evaluated separately. When Fe(OH)3 was applied in the aeration step and complete oxidation of Fe2+ was obtained after 27 min, while complete Mn2+ oxidation was obtained in 76 min. However, when MnO2 was applied in the aeration step, complete oxidation of Fe2+ and Mn2+ was relatively slow (36 and 110 min, respectively). According to the results obtained from the aerated membrane system, Fe2+ and Mn2+ removal were extended by Fe(OH)3 via adsorption/surface oxidation. It is clearly shown from the flux, resistance results, scanning electron microscope (SEM) and Fourier transform infrared (FT/IR) spectroscopy observation that manganese oxides were deposited mainly in membrane pores forming membrane fouling by small flocs, while iron oxide particles were deposited on the membrane surface. Although the flux performance of PT PES membrane was higher than HF PP membrane, fouling resistance of HF PP membrane was higher than PT PES.
Collapse
Affiliation(s)
- Güler Türkoğlu Demirkol
- Department of Environmental Engineering, Faculty of Engineering, Istanbul University-Cerrahpasa, Avcilar Campus, Istanbul 34320, Turkey; (E.Ç.); (S.A.D.); (N.T.)
- Correspondence: (G.T.D.); (S.A.)
| | - Suna Özden Çelik
- Department of Environmental Engineering, Corlu Engineering Faculty, Namik Kemal University, Corlu/Tekirdag 59860, Turkey;
| | - Sevgi Güneş Durak
- Department of Environmental Engineering, Faculty of Engineering-Architecture, Nevsehir Haci Bektas Veli University, Nevsehir 50300, Turkey;
| | - Seren Acarer
- Department of Environmental Engineering, Faculty of Engineering, Istanbul University-Cerrahpasa, Avcilar Campus, Istanbul 34320, Turkey; (E.Ç.); (S.A.D.); (N.T.)
- Correspondence: (G.T.D.); (S.A.)
| | - Ender Çetin
- Department of Environmental Engineering, Faculty of Engineering, Istanbul University-Cerrahpasa, Avcilar Campus, Istanbul 34320, Turkey; (E.Ç.); (S.A.D.); (N.T.)
| | - Sultan Akarçay Demir
- Department of Environmental Engineering, Faculty of Engineering, Istanbul University-Cerrahpasa, Avcilar Campus, Istanbul 34320, Turkey; (E.Ç.); (S.A.D.); (N.T.)
| | - Neşe Tüfekci
- Department of Environmental Engineering, Faculty of Engineering, Istanbul University-Cerrahpasa, Avcilar Campus, Istanbul 34320, Turkey; (E.Ç.); (S.A.D.); (N.T.)
| |
Collapse
|
12
|
Liang Y, Zhang Y, Li M, Meng Z, Gao Y, Yin J, Yang Y, Wang Z, Wang S. A highly effective "turn-on" camphor-based fluorescent probe for rapid and sensitive detection and its biological imaging of Fe 2. Anal Bioanal Chem 2021; 413:6267-6277. [PMID: 34355255 DOI: 10.1007/s00216-021-03581-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 07/12/2021] [Accepted: 07/26/2021] [Indexed: 01/17/2023]
Abstract
In this work, a novel fluorescent probe CBO was synthesized for detecting Fe2+ using the natural monoterpenketone camphor as the starting material. The probe CBO displayed turn-on fluorescence to Fe2+ accompanied by the solution change from colorless to green. As expected, there was an excellent linear relationship between the fluorescence intensity of probe CBO and the concentration of Fe2+ (0-20 μM), and the detection limit was as low as 1.56×10-8 M. In particular, CBO could selectively sense Fe2+ more than other analytes (Fe3+ included) through the N-oxide strategy, and quickly responded to Fe2+ (60 s) over a wide pH (4-14) range. Additionally, based on the rapid fluorescence response of CBO to Fe2+, a simple test strip-based detector was designed for boosting practical applicability. The probe CBO had been successfully applied to the fluorescence imaging of Fe2+ in onion cells and living zebrafish. The probe CBO was a powerful tool of detecting Fe2+ level in organisms, which was of significance to understand the role of Fe2+ in Fe2+-related physical processes and diseases.
Collapse
Affiliation(s)
- Yueyin Liang
- Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, College of Light Industry and Food, Nanjing Forestry University, Nanjing, 210037, China
| | - Yan Zhang
- Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, College of Light Industry and Food, Nanjing Forestry University, Nanjing, 210037, China
| | - Mingxin Li
- Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, College of Light Industry and Food, Nanjing Forestry University, Nanjing, 210037, China
| | - Zhiyuan Meng
- Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, College of Light Industry and Food, Nanjing Forestry University, Nanjing, 210037, China
| | - Yu Gao
- Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, College of Light Industry and Food, Nanjing Forestry University, Nanjing, 210037, China
| | - Jie Yin
- Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, College of Light Industry and Food, Nanjing Forestry University, Nanjing, 210037, China
| | - Yiqin Yang
- Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, College of Light Industry and Food, Nanjing Forestry University, Nanjing, 210037, China
| | - Zhonglong Wang
- Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, College of Light Industry and Food, Nanjing Forestry University, Nanjing, 210037, China.
| | - Shifa Wang
- Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, College of Light Industry and Food, Nanjing Forestry University, Nanjing, 210037, China.
| |
Collapse
|
13
|
Tomita K, Nagasawa T, Kuwahara Y, Torii S, Igarashi K, Roudkenar MH, Roushandeh AM, Kurimasa A, Sato T. MiR-7-5p Is Involved in Ferroptosis Signaling and Radioresistance Thru the Generation of ROS in Radioresistant HeLa and SAS Cell Lines. Int J Mol Sci 2021; 22:ijms22158300. [PMID: 34361070 PMCID: PMC8348045 DOI: 10.3390/ijms22158300] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/29/2021] [Accepted: 07/30/2021] [Indexed: 12/11/2022] Open
Abstract
In cancer therapy, radioresistance or chemoresistance cells are major problems. We established clinically relevant radioresistant (CRR) cells that can survive over 30 days after 2 Gy/day X-ray exposures. These cells also show resistance to anticancer agents and hydrogen peroxide (H2O2). We have previously demonstrated that all the CRR cells examined had up-regulated miR-7-5p and after miR-7-5p knockdown, they lost radioresistance. However, the mechanism of losing radioresistance remains to be elucidated. Therefore, we investigated the role of miR-7-5p in radioresistance by knockdown of miR-7-5p using CRR cells. As a result, knockdown of miR-7-5p increased reactive oxygen species (ROS), mitochondrial membrane potential, and intracellular Fe2+ amount. Furthermore, miR-7-5p knockdown results in the down-regulation of the iron storage gene expression such as ferritin, up-regulation of the ferroptosis marker ALOX12 gene expression, and increases of Liperfluo amount. H2O2 treatment after ALOX12 overexpression led to the enhancement of intracellular H2O2 amount and lipid peroxidation. By contrast, miR-7-5p knockdown seemed not to be involved in COX-2 and glycolysis signaling but affected the morphology of CRR cells. These results indicate that miR-7-5p control radioresistance via ROS generation that leads to ferroptosis.
Collapse
Affiliation(s)
- Kazuo Tomita
- Department of Applied Pharmacology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City 890-8544, Kagoshima, Japan; (T.N.); (Y.K.); (K.I.); (M.H.R.); (A.M.R.); (T.S.)
- Correspondence: ; Tel.: +81-99-275-6162
| | - Taisuke Nagasawa
- Department of Applied Pharmacology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City 890-8544, Kagoshima, Japan; (T.N.); (Y.K.); (K.I.); (M.H.R.); (A.M.R.); (T.S.)
| | - Yoshikazu Kuwahara
- Department of Applied Pharmacology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City 890-8544, Kagoshima, Japan; (T.N.); (Y.K.); (K.I.); (M.H.R.); (A.M.R.); (T.S.)
- Division of Radiation Biology and Medicine, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai-City 983-8536, Miyagi, Japan;
| | - Seiji Torii
- Center for Food Science and Wellness, Gunma University, Maebashi-City 371-8510, Gunma, Japan;
| | - Kento Igarashi
- Department of Applied Pharmacology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City 890-8544, Kagoshima, Japan; (T.N.); (Y.K.); (K.I.); (M.H.R.); (A.M.R.); (T.S.)
| | - Mehryar Habibi Roudkenar
- Department of Applied Pharmacology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City 890-8544, Kagoshima, Japan; (T.N.); (Y.K.); (K.I.); (M.H.R.); (A.M.R.); (T.S.)
- Burn and Regenerative Medicine Research Center, Velayat Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht 41937-13194, Iran
| | - Amaneh Mohammadi Roushandeh
- Department of Applied Pharmacology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City 890-8544, Kagoshima, Japan; (T.N.); (Y.K.); (K.I.); (M.H.R.); (A.M.R.); (T.S.)
- Burn and Regenerative Medicine Research Center, Velayat Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht 41937-13194, Iran
| | - Akihiro Kurimasa
- Division of Radiation Biology and Medicine, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai-City 983-8536, Miyagi, Japan;
| | - Tomoaki Sato
- Department of Applied Pharmacology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City 890-8544, Kagoshima, Japan; (T.N.); (Y.K.); (K.I.); (M.H.R.); (A.M.R.); (T.S.)
| |
Collapse
|
14
|
Abstract
Iron is an ancient, essential and versatile transition metal found in almost all living organisms on Earth. This fundamental trace element is used in the synthesis of heme and iron-sulfur (Fe-S) containing proteins and other vital cofactors that are involved in respiration, redox reactions, catalysis, DNA synthesis and transcription. At the same time, the ability of iron to cycle between its oxidized, ferric (Fe3+) and its reduced, ferrous (Fe2+) state contributes to the production of free radicals that can damage biomolecules, including proteins, lipids and DNA. In particular, the regulated non-apoptotic cell death ferroptosis is driven by Fe2+-dependent lipid peroxidation that can be prevented by iron chelation or genetic inhibition of cellular iron uptake. Therefore, iron homeostasis must be tightly regulated to avoid iron toxicity. This review provides an overview of the origin and chemistry of iron that makes it suitable for a variety of biological functions and addresses how organisms evolved various strategies, including their scavenging and antioxidant machinery, to manage redox-associated drawbacks. Finally, key mechanisms of iron metabolism are highlighted in human diseases and model organisms, underlining the perils of dysfunctional iron handlings.
Collapse
Affiliation(s)
- Vivek Venkataramani
- Institute of Pathology, University Medical Center Göttingen (UMG), Göttingen, Germany.
| |
Collapse
|
15
|
Gu Y, Chen J, Zhang H, Shen Z, Liu H, Lv S, Yu X, Zhang D, Ding X, Zhang X. Hydrogen sulfide attenuates renal fibrosis by inducing TET-dependent DNA demethylation on Klotho promoter. FASEB J 2020; 34:11474-11487. [PMID: 32729950 DOI: 10.1096/fj.201902957rr] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 04/28/2020] [Accepted: 05/06/2020] [Indexed: 12/11/2022]
Abstract
Hypoxia is a key pathogenetic characteristic of chronic kidney disease (CKD). Klotho has renoprotective effect and its expression is commonly suppressed in CKD patients. We showed that chronic hypoxia in unilateral ureteral obstruction model mice is associated with renal Klotho promoter methylation and expression silencing. Administration of low-dose of sodium hydrosulfide (NaHS) effectively ameliorated renal tubulointerstitial fibrosis in the mouse model by demethylating Klotho promoter and restoring its expression. Mechanistically, hypoxia microenvironment in CKD reduced cellular oxygen availability and Fe2+ concentration, and led to impaired activity of ten-eleven translocation (TET), which is critical in maintaining Klotho promoter demethylation status. NaHS treatment greatly improved hypoxia condition, restored TET activity, reversed DNA methylation, and thus, increased Klotho expression. Our results strongly suggested that correcting hypoxia condition to restore TET activity could be a promising therapeutic strategy against CKD.
Collapse
Affiliation(s)
- Yulu Gu
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China
| | - Jing Chen
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney Disease, Shanghai, China
| | - Han Zhang
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney Disease, Shanghai, China
| | - Ziyan Shen
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney Disease, Shanghai, China
| | - Hong Liu
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Medical Center of Kidney Disease, Shanghai, China
| | - Shiqi Lv
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China
| | - Xixi Yu
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China
| | - Di Zhang
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China
| | - Xiaoqiang Ding
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China.,Shanghai Medical Center of Kidney Disease, Shanghai, China.,Shanghai Institute of Kidney and Dialysis, Shanghai, China
| | - Xiaoyan Zhang
- Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, China.,Shanghai Medical Center of Kidney Disease, Shanghai, China.,Shanghai Institute of Kidney and Dialysis, Shanghai, China
| |
Collapse
|
16
|
Wang M, Wang D, Qiu S, Xiao J, Cai H, Zou J. Multi-wavelength spectrophotometric determination of hydrogen peroxide in water by oxidative coloration of ABTS via Fenton reaction. Environ Sci Pollut Res Int 2019; 26:27063-27072. [PMID: 31313234 DOI: 10.1007/s11356-019-05884-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 07/01/2019] [Indexed: 06/10/2023]
Abstract
In this study, a sensitive and low-cost multi-wavelength spectrophotometric method for the determination of hydrogen peroxide (H2O2) in water was established. The method was based on the oxidative coloration of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) via Fenton reaction, which resulted in the formation of green radical (ABTS•+) with absorbance at four different wavelengths (i.e., 415 nm, 650 nm, 732 nm, and 820 nm). Under the optimized conditions (CABTS = 2.0 mM, CFe2+ = 1.0 mM, pH = 2.60 ± 0.02, and reaction time (t) = 1 min), the absorbance of the generated ABTS•+ at 415 nm, 650 nm, 732 nm, and 820 nm were well linear with H2O2 concentrations in the range of 0-40 μM (R2 > 0.999) and the sensitivities of the proposed Fenton-ABTS method were calculated as 4.19 × 104 M-1 cm-1,1.73 × 104 M-1 cm-1, 2.18 × 104 M-1 cm-1, and 1.96 × 104 M-1 cm-1, respectively. Meanwhile, the detection limits of the Fenton-ABTS method at 415 nm, 650 nm, 732 nm, and 820 nm were respectively calculated to be 0.18 μM, 0.12 μM, 0.10 μM, and 0.11 μM. The absorbance of the generated ABTS•+ in ultrapure water, underground water, and reservoir water was quite stable within 30 min. Moreover, the proposed Fenton-ABTS method could be used for monitoring the variations of H2O2 concentration during the oxidative decolorization of RhB in alkali-activated H2O2 system.
Collapse
Affiliation(s)
- Mengyun Wang
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, People's Republic of China
| | - Daiyao Wang
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, People's Republic of China
| | - Shiyi Qiu
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, People's Republic of China
| | - Junyang Xiao
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, People's Republic of China
| | - Huahua Cai
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, People's Republic of China
| | - Jing Zou
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, 361021, People's Republic of China.
| |
Collapse
|
17
|
Tanitame K, Tanitame N, Takahashi Y, Tamai E, Kurose T. The opacity of mineral ion-loaded bead (DC beads ®) on low-keV monochromatic images from dual energy CT and T1-weighted gradient-echo MRI. Jpn J Radiol 2019; 37:660-665. [PMID: 31338722 DOI: 10.1007/s11604-019-00856-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 07/11/2019] [Indexed: 10/26/2022]
Abstract
PURPOSE To evaluate the opacity of DC beads® (DCB) loaded with mineral ions on low-keV monochromatic images from dual energy computed tomography (DECT) and T1-weighted gradient-echo (T1-GRE) MRI. MATERIALS AND METHODS Fe2+ or Ca2+-loaded DCBs were prepared by mixing DCBs in 100 mM FeSO4 or CaSO4 solution and scanned by DECT from 10 min to 27 h after mixing. The Hounsfield units (HUs) of sedimented DCBs on 40-keV monochromatic images were measured. Next, we mixed DCBs in 100, 10, 5 and 1 mM FeSO4 solutions, and scanned these solutions from 15 to 120 min after mixing using a 3 T MR scanner. The signal-noise ratios (SNRs) of sedimented DCBs on T1-GRE were measured. Venous blood was scanned to compare with DCBs. RESULTS The CT values of DCBs in FeSO4 and CaCl2 solutions gradually increased, and were 113.3 and 43.1 HU at 27 h, respectively; that of blood was 17.8 HU. The SNR of DCB in 1 mM FeSO4 solution increased and achieved equilibrium at 120 min, and was 120.5 and higher than in the other FeSO4 solutions. The SNR of blood was 49.7. CONCLUSION Optimally Fe2+-loaded DCBs can be discriminated from venous blood on 40-keV monochromatic images from DECT and T1-GRE.
Collapse
Affiliation(s)
- Keizo Tanitame
- Department of Diagnostic Radiology, Hiroshima Prefectural Hospital, Minami-ku, Ujinakanda, 1-5-54, Hiroshima, 734-8530, Japan.
| | - Nobuko Tanitame
- Department of Radiology, Hiroshima City Hiroshima Citizens Hospital, Hiroshima, Japan
| | - Yuji Takahashi
- Department of Clinical Radiology, Hiroshima University Hospital, Hiroshima, Japan
| | - Erika Tamai
- Department of Radiology, Hiroshima Prefectural Hospital, Hiroshima, Japan
| | - Taichi Kurose
- Department of Diagnostic Radiology, Hiroshima Prefectural Hospital, Minami-ku, Ujinakanda, 1-5-54, Hiroshima, 734-8530, Japan
| |
Collapse
|
18
|
Bischof H, Burgstaller S, Waldeck-Weiermair M, Rauter T, Schinagl M, Ramadani-Muja J, Graier WF, Malli R. Live-Cell Imaging of Physiologically Relevant Metal Ions Using Genetically Encoded FRET-Based Probes. Cells 2019; 8:E492. [PMID: 31121936 DOI: 10.3390/cells8050492] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 05/17/2019] [Accepted: 05/21/2019] [Indexed: 01/02/2023] Open
Abstract
Essential biochemical reactions and processes within living organisms are coupled to subcellular fluctuations of metal ions. Disturbances in cellular metal ion homeostasis are frequently associated with pathological alterations, including neurotoxicity causing neurodegeneration, as well as metabolic disorders or cancer. Considering these important aspects of the cellular metal ion homeostasis in health and disease, measurements of subcellular ion signals are of broad scientific interest. The investigation of the cellular ion homeostasis using classical biochemical methods is quite difficult, often even not feasible or requires large cell numbers. Here, we report of genetically encoded fluorescent probes that enable the visualization of metal ion dynamics within individual living cells and their organelles with high temporal and spatial resolution. Generally, these probes consist of specific ion binding domains fused to fluorescent protein(s), altering their fluorescent properties upon ion binding. This review focuses on the functionality and potential of these genetically encoded fluorescent tools which enable monitoring (sub)cellular concentrations of alkali metals such as K+, alkaline earth metals including Mg2+ and Ca2+, and transition metals including Cu+/Cu2+ and Zn2+. Moreover, we discuss possible approaches for the development and application of novel metal ion biosensors for Fe2+/Fe3+, Mn2+ and Na+.
Collapse
|
19
|
Doyle Drbohlav LM, Sharma AN, Gopalrathnam G, Huang L, Bradley S. A Mechanistic Understanding of Polysorbate 80 Oxidation in Histidine and Citrate Buffer Systems-Part 2. PDA J Pharm Sci Technol 2019; 73:320-330. [PMID: 30770486 DOI: 10.5731/pdajpst.2018.009639] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In our previously published work, we reported rapid polysorbate 80 (PS80) oxidation in a histidine buffer after brief exposure to stainless steel and the ability of citrate and EDTA to prevent this oxidation. The focus of our current study was to mechanistically understand PS80 oxidation by studying the impacts of temperature, light, and stainless steel and the role of citrate and EDTA. Additionally, PS80 oxidation was studied in three different buffer systems: histidine, citrate, and phosphate. When the PS80-containing buffers in glass containers were exposed to the elevated temperature of 50°C, no PS80 oxidation was observed in either the histidine or the citrate buffer systems after 30 days; however, PS80 oxidation was observed in the phosphate buffer system within 14 days. These results demonstrated that temperature does not initiate PS80 oxidation in the histidine or the citrate buffer systems, but it may be a factor in the phosphate buffer system. When the three buffer systems containing PS80 were exposed to 20%, 50%, or 100% ICH Q1B light conditions and subsequently incubated in the dark at 50°C, the PS80 in the phosphate buffer system underwent oxidation within 7 days, whereas the PS80 in the histidine and the citrate buffer systems showed oxidation products only after 14 and 35 days, respectively. PS80 in the phosphate buffer system seemed to be the most vulnerable to light as PS80 in both the histidine and the citrate buffer systems underwent oxidation to a lesser extent, with faster oxidation occurring in the histidine buffer system than in the citrate buffer system. Finally, the ability of citrate and EDTA to act as not only chelators but also radical quenchers/scavengers was demonstrated when a metal ion, Fe2+, was spiked into the histidine buffer containing PS80. While radicals could not be unambiguously identified by NMR or EPR, the observation of PS80 oxidation products indicated their presence.LAY ABSTRACT: In our previously published work, we reported rapid polysorbate 80 (PS80) oxidation in a histidine buffer after brief exposure to stainless steel and the ability of citrate and EDTA to prevent this oxidation. The focus of our current study was to mechanistically understand PS80 oxidation by studying the impacts of temperature, light, and stainless steel and the role of citrate and EDTA. Additionally, PS80 oxidation was studied in three different buffer systems: histidine, citrate, and phosphate. The temperature study demonstrated that PS80 oxidation in the histidine or the citrate buffer systems is not initiated by temperature, but may be a factor in the phosphate buffer system. PS80 in the phosphate buffer system seemed to be the most vulnerable to light, as PS80 in both the histidine and the citrate buffer systems underwent oxidation at a lower level, with the histidine buffer system showing more rapid oxidation than the citrate buffer system. Finally, the ability of citrate and EDTA to act as not only chelators but also radical quenchers/scavengers was demonstrated when a metal ion, Fe2+, was spiked into the histidine buffer containing PS80. While neither NMR nor EPR could definitively identify the presence of free radicals, the observation of PS80 oxidation products indicates that they were present.
Collapse
Affiliation(s)
- Laura M Doyle Drbohlav
- Department of Pharmaceutical Chemistry, University of Kansas, Simons Biosciences Research Laboratories, 2095 Constant Ave. Lawrence, KS 66047
| | - Anant Navanithan Sharma
- Bioproduct Pharma Design, Lilly Research Laboratories, Eli Lilly and Company, 1400 West Raymond St., Indianapolis, IN 46221;
| | - Ganapathy Gopalrathnam
- Bioproduct Pharma Design, Lilly Research Laboratories, Eli Lilly and Company, 1400 West Raymond St., Indianapolis, IN 46221
| | - Lihua Huang
- Protein Characterization, Lilly Research Laboratories, Eli Lilly and Company, 1400 West Raymond St., Indianapolis, IN 46221
| | - Scott Bradley
- Analytical Development, Lilly Research Laboratories, Eli Lilly and Company, 1400 West Raymond St., Indianapolis, IN 46221
| |
Collapse
|
20
|
Swarupa V, Chaudhury A, Sarma PVGK. Iron enhances the peptidyl deformylase activity and biofilm formation in Staphylococcus aureus. 3 Biotech 2018; 8:32. [PMID: 29291145 DOI: 10.1007/s13205-017-1050-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Accepted: 12/17/2017] [Indexed: 11/30/2022] Open
Abstract
Staphylococcus aureus plays a major role in persistent infections and many of these species form structured biofilms on different surfaces which is accompanied by changes in gene expression profiles. Further, iron supplementation plays a critical role in the regulation of several protein(s)/enzyme function, which all aid in the development of active bacterial biofilms. It is well known that for each protein, deformylation is the most crucial step in biosynthesis and is catalyzed by peptidyl deformylase (PDF). Thus, the aim of the current study is to understand the role of iron in biofilm formation and deformylase activity of PDF. Hence, the PDF gene of S. aureus ATCC12600 was PCR amplified using specific primers and sequenced, followed by cloning and expression in Escherichia coli DH5α. The deformylase activity of the purified recombinant PDF was measured in culture supplemented with/without iron where the purified rPDF showed Km of 1.3 mM and Vmax of 0.035 mM/mg/min, which was close to the native PDF (Km = 1.4 mM, Vmax = 0.030 mM/mg/min). Interestingly, the Km decreased and PDF activity increased when the culture was supplemented with iron, corroborating with qPCR results showing 100- to 150-fold more expression compared to control in S. aureus and its drug-resistant strains. Further biofilm-forming units (BU) showed an incredible increase (0.42 ± 0.005 to 6.3 ± 0.05 BU), i.e., almost 15-fold elevation in anaerobic conditions, indicating the significance of iron in S. aureus biofilms.
Collapse
Affiliation(s)
- Vimjam Swarupa
- Department of Biotechnology, Sri Venkateswara Institute of Medical Sciences, Tirupati, 517507 AP India
| | - Abhijit Chaudhury
- Department of Microbiology, Sri Venkateswara Institute of Medical Sciences, Tirupati, 517507 India
| | | |
Collapse
|
21
|
Martinez-Cuenca MR, Primo-Capella A, Quiñones A, Bermejo A, Forner-Giner MA. Rootstock influence on iron uptake responses in Citrus leaves and their regulation under the Fe paradox effect. PeerJ 2017; 5:e3553. [PMID: 28966887 PMCID: PMC5619235 DOI: 10.7717/peerj.3553] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 06/16/2017] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND AND AIMS This work evaluates the regulation of iron uptake responses in Citrus leaves and their involvement in the Fe paradox effect. METHODS Experiments were performed in field-grown 'Navelina' trees grafted onto two Cleopatra mandarin × Poncirus trifoliata (L.) Raf. hybrids with different Fe-chlorosis symptoms: 030146 (non-chlorotic) and 030122 (chlorotic). RESULTS Chlorotic leaves were smaller than non-chlorotic ones for both dry weight (DW) and area basis, and exhibited marked photosynthetic state affection, but reduced catalase and peroxidase enzymatic activities. Although both samples had a similar total Fe concentration on DW, it was lower in chlorotic leaves when expressed on an area basis. A similar pattern was observed for the total Fe concentration in the apoplast and cell sap and in active Fe (Fe2+) concentration. FRO2 gene expression and ferric chelate reductase (FC-R) activity were also lower in chlorotic samples, while HA1 and IRT1 were more induced. Despite similar apoplasmic pH, K+/Ca2+ was higher in chlorotic leaves, and both citrate and malate concentrations in total tissue and apoplast fluid were lower. CONCLUSION (1) The rootstock influences Fe acquisition system in the leaf; (2) the increased sensitivity to Fe-deficiency as revealed by chlorosis and decreased biomass, was correlated with lower FC-R activity and lower organic acid level in leaf cells, which could cause a decreased Fe mobility and trigger other Fe-stress responses in this organ to enhance acidification and Fe uptake inside cells; and (3) the chlorosis paradox phenomenon in citrus likely occurs as a combination of a marked FC-R activity impairment in the leaf and the strong growth inhibition in this organ.
Collapse
Affiliation(s)
- Mary-Rus Martinez-Cuenca
- Centre of Citriculture and Plant Production, Valencian Agricultural and Research Institute (IVIA), Moncada, Valencia, Spain
| | - Amparo Primo-Capella
- Centre of Citriculture and Plant Production, Valencian Agricultural and Research Institute (IVIA), Moncada, Valencia, Spain
| | - Ana Quiñones
- Centre of Sustainable Agricultural Development, Valencian Agricultural and Research Institute (IVIA), Moncada, Valencia, Spain
| | - Almudena Bermejo
- Centre of Citriculture and Plant Production, Valencian Agricultural and Research Institute (IVIA), Moncada, Valencia, Spain
| | - Maria Angeles Forner-Giner
- Centre of Citriculture and Plant Production, Valencian Agricultural and Research Institute (IVIA), Moncada, Valencia, Spain
| |
Collapse
|
22
|
Cui Z, Zhong Z, Yang Y, Wang B, Sun Y, Sun Q, Yang GY, Bian L. Ferrous Iron Induces Nrf2 Expression in Mouse Brain Astrocytes to Prevent Neurotoxicity. J Biochem Mol Toxicol 2016; 30:396-403. [PMID: 27037625 DOI: 10.1002/jbt.21803] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Revised: 02/22/2016] [Accepted: 03/05/2016] [Indexed: 11/09/2022]
Abstract
Free radical damage caused by ferrous iron is involved in the pathogenesis of secondary brain injury after intracerebral hemorrhage (ICH). NF-E2-related factor 2 (Nrf2), a major phase II gene regulator that binds to antioxidant response element, represents an important cellular cytoprotective mechanism against oxidative damage. We hypothesized that Nrf2 might protect astrocytes from damage by Fe(2+) . Therefore, we examined cytotoxicity in primary astrocytes induced by iron overload and evaluated the effects of Fe(2+) on Nrf2 expression. The results demonstrated that 24-h Fe(2+) exposure exerted time- and concentration-dependent cytotoxicity in astrocytes. Furthermore, Fe(2+) exposure in astrocytes resulted in time- and concentration-dependent increases in Nrf2 expression, which preceded Fe(2+) toxicity. Nrf2-specific siRNA further knocked down Nrf2 levels, resulting in greater Fe(2+) -induced astrocyte cytotoxicity. These data indicate that induction of Nrf2 expression could serve as an adaptive self-defense mechanism, although it is insufficient to completely protect primary astrocytes from Fe(2+) -induced neurotoxicity.
Collapse
Affiliation(s)
- Zhenwen Cui
- Department of Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Zhihong Zhong
- Department of Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Yong Yang
- Department of Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Baofeng Wang
- Department of Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Yuhao Sun
- Department of Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Qingfang Sun
- Department of Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.,Department of Neurosurgery, Ruijin Hospital Luwan Branch, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Guo-Yuan Yang
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.,Neuroscience and Neuroengineering Research Center, Med-X Research Institute, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Liuguan Bian
- Department of Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
| |
Collapse
|
23
|
Rafique N, Tariq SR, Ahad K, Taj T. Cu(2+) and Fe(2+) mediated photodegradation studies of soil-incorporated chlorpyrifos. Environ Sci Pollut Res Int 2016; 23:4473-4480. [PMID: 26507736 DOI: 10.1007/s11356-015-5655-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 10/20/2015] [Indexed: 06/05/2023]
Abstract
The influences of Cu(2+) and Fe(2+) on the photodegradation of soil-incorporated chlorpyrifos were investigated in the present study. The soil samples spiked with chlorpyrifos and selected metal ions were irradiated with UV light for different intervals of time and analyzed by HPLC. The unsterile and sterile control soil samples amended with pesticides and selected metals were incubated in the dark at 25 °C for the same time intervals. The results of the study evidenced that photodegradation of chlorpyrifos followed the first-order kinetics. The dissipation t0.5 of chlorpyrifos was found to decrease from 41 to 20 days under UV irradiation. The rate of chlorpyrifos photodegradation was increased in the presence of both metals, i.e., Cu(2+) and Fe(2+). Thus, initially observed t0.5 of 19.8 days was decreased to 4.39 days in the case of Cu(+2) and 19.25 days for Fe(+2). Copper was found to increase the rate of photodegradation by 4.5 orders of magnitude while the microbial degradation of chlorpyrifos was increased only twofold. The microbial degradation of chlorpyrifos was only negligibly affected by Fe(2+) amendment. The studied trace metals also affected the abiotic degradation of the pesticide in the order Cu(2+) > Fe(2+).
Collapse
Affiliation(s)
- Nazia Rafique
- Department of Chemistry, Lahore College for Women University, Lahore, Pakistan.
| | - Saadia R Tariq
- Department of Chemistry, Lahore College for Women University, Lahore, Pakistan.
| | - Karam Ahad
- Ecotoxicology Research Institute (ERI), Department of Plant and Environment Protection (DPEP), NARC, Islamabad, Pakistan.
| | - Touqeer Taj
- Ecotoxicology Research Institute (ERI), Department of Plant and Environment Protection (DPEP), NARC, Islamabad, Pakistan.
| |
Collapse
|
24
|
Wada M, Komatsu H, Ikeda R, Aburjai TA, Alkhalil SM, Kuroda N, Nakashima K. In vitro screening of Fe2+-chelating effect by a Fenton's reaction-luminol chemiluminescence system. LUMINESCENCE 2014; 29:955-8. [PMID: 24403191 DOI: 10.1002/bio.2628] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Revised: 10/11/2013] [Accepted: 11/25/2013] [Indexed: 11/11/2022]
Abstract
In vitro screening of a Fe(2+) -chelating effect using a Fenton's reaction-luminol chemiluminescence (CL) system is described. The luminescence between the reactive oxygen species generated by the Fenton's reaction and luminol was decreased on capturing Fe(2+) using a chelator. The proposed method can prevent the consumption of expensive seed compounds (drug discovery candidates) owing to the high sensitivity of CL detection. Therefore, the assay could be performed using small volumes of sample solution (150 μL) at micromolar concentrations. After optimization of the screening conditions, the efficacies of conventional chelators such as ethylenediaminetetraacetic acid (EDTA), diethylentriaminepentaacetic acid (DETAPAC), deferoxamine, deferiprone and 1,10-phenanthroline were examined. EC50 values for these compounds (except 1,10-phenanthroline) were in the range 3.20 ± 0.87 to 9.57 ± 0.64 μM (n = 3). Rapid measurement of the Fe(2+)-chelating effect with an assay run time of a few minutes could be achieved using the proposed method. In addition, the specificity of the method was discussed.
Collapse
Affiliation(s)
- Mitsuhiro Wada
- Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, 852-8521, Japan
| | | | | | | | | | | | | |
Collapse
|