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Huang C, Huang W, Ji P, Song F, Liu T, Li M, Guo H, Huang Y, Yu C, Wang C, Ni W. A Pyrazolate Osmium(VI) Nitride Exhibits Anticancer Activity through Modulating Protein Homeostasis in HepG2 Cells. Int J Mol Sci 2022; 23:ijms232112779. [PMID: 36361570 PMCID: PMC9656236 DOI: 10.3390/ijms232112779] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/18/2022] [Accepted: 10/19/2022] [Indexed: 02/05/2023] Open
Abstract
Interest in the third-row transition metal osmium and its compounds as potential anticancer agents has grown in recent years. Here, we synthesized the osmium(VI) nitrido complex Na[OsVI(N)(tpm)2] (tpm = [5-(Thien-2-yl)-1H-pyrazol-3-yl]methanol), which exhibited a greater inhibitory effect on the cell viabilities of the cervical, ovarian, and breast cancer cell lines compared with cisplatin. Proteomics analysis revealed that Na[OsVI(N)(tpm)2] modulates the expression of protein-transportation-associated, DNA-metabolism-associated, and oxidative-stress-associated proteins in HepG2 cells. Perturbation of protein expression activity by the complex in cancer cells affects the functions of the mitochondria, resulting in high levels of cellular oxidative stress and low rates of cell survival. Moreover, it caused G2/M phase cell cycle arrest and caspase-mediated apoptosis of HepG2 cells. This study reveals a new high-valent osmium complex as an anticancer agent candidate modulating protein homeostasis.
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Affiliation(s)
- Chengyang Huang
- Department of Physiology, Shantou University Medical College, Shantou 515041, China
- Department of Biological Chemistry, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Wanqiong Huang
- Department of Medicinal Chemistry, Shantou University Medical College, Shantou 515041, China
| | - Pengchao Ji
- Department of Medicinal Chemistry, Shantou University Medical College, Shantou 515041, China
| | - Fuling Song
- Department of Medicinal Chemistry, Shantou University Medical College, Shantou 515041, China
| | - Tao Liu
- Department of Medicinal Chemistry, Shantou University Medical College, Shantou 515041, China
| | - Meiyang Li
- Department of Physiology, Shantou University Medical College, Shantou 515041, China
| | - Hongzhi Guo
- Department of Physiology, Shantou University Medical College, Shantou 515041, China
| | - Yongliang Huang
- Department of Medicinal Chemistry, Shantou University Medical College, Shantou 515041, China
| | - Cuicui Yu
- Department of Physiology, Shantou University Medical College, Shantou 515041, China
| | - Chuanxian Wang
- Department of Medicinal Chemistry, Shantou University Medical College, Shantou 515041, China
| | - Wenxiu Ni
- Department of Medicinal Chemistry, Shantou University Medical College, Shantou 515041, China
- Correspondence:
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Schumann R, Bischoff E, Klaus S, Möhring S, Flock J, Keller S, Remans K, Ganter M, Deponte M. Protein abundance and folding rather than the redox state of Kelch13 determine the artemisinin susceptibility of Plasmodium falciparum. Redox Biol 2021; 48:102177. [PMID: 34773836 PMCID: PMC8600086 DOI: 10.1016/j.redox.2021.102177] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/25/2021] [Accepted: 10/30/2021] [Indexed: 12/30/2022] Open
Abstract
Decreased susceptibilities of the human malaria parasite Plasmodium falciparum towards the endoperoxide antimalarial artemisinin are linked to mutations of residue C580 of PfKelch13, a homologue of the redox sensor Keap1 and other vertebrate BTB-Kelch proteins. Here, we addressed whether mutations alter the artemisinin susceptibility by modifying the redox properties of PfKelch13 or by compromising its native fold or abundance. Using selection-linked integration and the glmS ribozyme, efficient down-regulation of PfKelch13 resulted in ring-stage survival rates around 40%. While the loss of the thiol group of C469 or of the potential disulfide bond between residues C580 and C532 had no effect on the artemisinin susceptibility, the thiol group of C473 could not be replaced. Furthermore, we detected two different forms of PfKelch13 with distinct electrophoretic mobilities around 85 and 95 kDa, suggesting an unidentified post-translational modification. We also established a protocol for the production of recombinant PfKelch13 and produced an antibody against the protein. Recombinant PfKelch13 adopted alternative oligomeric states and only two of its seven cysteine residues, C469 and C473, reacted with Ellman's reagent. While common field mutations resulted in misfolded and completely insoluble recombinant PfKelch13, cysteine-to-serine replacements had no effect on the solubility except for residue C473. In summary, in contrast to residues C469, C532, and C580, the surface-exposed thiol group of residue C473 appears to be essential. However, not the redox properties but impaired folding of PfKelch13, resulting in a decreased PfKelch13 abundance, alters the artemisinin susceptibility and is the central parameter for mutant selection.
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Affiliation(s)
- Robin Schumann
- Faculty of Chemistry, Comparative Biochemistry, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany
| | - Eileen Bischoff
- Faculty of Chemistry, Comparative Biochemistry, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany
| | - Severina Klaus
- Centre for Infectious Diseases, Parasitology, Heidelberg University Hospital, D-69120, Heidelberg, Germany
| | - Sophie Möhring
- Faculty of Chemistry, Comparative Biochemistry, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany
| | - Julia Flock
- Protein Expression and Purification Core Facility, European Molecular Biology Laboratory (EMBL), D-69117, Heidelberg, Germany
| | - Sandro Keller
- Molecular Biophysics, Technische Universität Kaiserslautern, D-67663, Kaiserslautern, Germany; Biophysics, Institute of Molecular Biosciences (IMB), NAWI Graz, University of Graz, Humboldtstr. 50/III, 8010, Graz, Austria; Field of Excellence BioHealth, University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Kim Remans
- Protein Expression and Purification Core Facility, European Molecular Biology Laboratory (EMBL), D-69117, Heidelberg, Germany
| | - Markus Ganter
- Centre for Infectious Diseases, Parasitology, Heidelberg University Hospital, D-69120, Heidelberg, Germany
| | - Marcel Deponte
- Faculty of Chemistry, Comparative Biochemistry, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany.
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Bai X, Ni J, Beretov J, Wasinger VC, Wang S, Zhu Y, Graham P, Li Y. Activation of the eIF2α/ATF4 axis drives triple-negative breast cancer radioresistance by promoting glutathione biosynthesis. Redox Biol 2021; 43:101993. [PMID: 33946018 PMCID: PMC8111851 DOI: 10.1016/j.redox.2021.101993] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/21/2021] [Accepted: 04/21/2021] [Indexed: 12/14/2022] Open
Abstract
Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype. Radiotherapy is an effective option for the treatment of TNBC; however, acquired radioresistance is a major challenge to the modality. In this study, we show that the integrated stress response (ISR) is the most activated signaling pathway in radioresistant TNBC cells. The constitutive phosphorylation of eIF2α in radioresistant TNBC cells promotes the activation of ATF4 and elicits the transcription of genes implicated in glutathione biosynthesis, including GCLC, SLC7A11, and CTH, which increases the intracellular level of reduced glutathione (GSH) and the scavenging of reactive oxygen species (ROS) after irradiation (IR), leading to a radioresistant phenotype. The cascade is significantly up-regulated in human TNBC tissues and is associated with unfavorable survival in patients. Dephosphorylation of eIF2α increases IR-induced ROS accumulation in radioresistant TNBC cells by disrupting ATF4-mediated GSH biosynthesis and sensitizes them to IR in vitro and in vivo. These findings reveal ISR as a vital mechanism underlying TNBC radioresistance and propose the eIF2α/ATF4 axis as a novel therapeutic target for TNBC treatment. The eIF2α/ATF4 axis is constitutively activated in radioresistant TNBC. Phosphorylated eIF2α increases the expression of ATF4 and GCLC at the translational level in TNBC. The eIF2α/ATF4 axis activation causes radioresistance in TNBC by promoting GSH biosynthesis and ROS scavenging. ATF4 promotes GSH biosynthesis in radioresistant TNBC by triggering the expression of GCLC, CTH, and SLC7A11. Inhibition of the eIF2α/ATF4 axis can improve the sensitivity of TNBC to radiotherapy in vitro and in vivo.
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Affiliation(s)
- Xupeng Bai
- St George and Sutherland Clinical School, Faculty of Medicine, UNSW Sydney, Kensington, NSW, 2052, Australia; Cancer Care Centre, St. George Hospital, Kogarah, NSW, 2217, Australia
| | - Jie Ni
- St George and Sutherland Clinical School, Faculty of Medicine, UNSW Sydney, Kensington, NSW, 2052, Australia; Cancer Care Centre, St. George Hospital, Kogarah, NSW, 2217, Australia
| | - Julia Beretov
- St George and Sutherland Clinical School, Faculty of Medicine, UNSW Sydney, Kensington, NSW, 2052, Australia; Cancer Care Centre, St. George Hospital, Kogarah, NSW, 2217, Australia; Anatomical Pathology, NSW Health Pathology, St. George Hospital, Kogarah, NSW, 2217, Australia
| | - Valerie C Wasinger
- Bioanalytical Mass Spectrometry Facility, Mark Wainwright Analytical Centre, UNSW Sydney, Kensington, NSW, 2052, Australia; School of Medical Science, UNSW Sydney, Kensington, NSW, 2052, Australia
| | - Shanping Wang
- School of Biomedicine and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, 510006, China
| | - Ying Zhu
- St George and Sutherland Clinical School, Faculty of Medicine, UNSW Sydney, Kensington, NSW, 2052, Australia; Cancer Care Centre, St. George Hospital, Kogarah, NSW, 2217, Australia
| | - Peter Graham
- St George and Sutherland Clinical School, Faculty of Medicine, UNSW Sydney, Kensington, NSW, 2052, Australia; Cancer Care Centre, St. George Hospital, Kogarah, NSW, 2217, Australia
| | - Yong Li
- St George and Sutherland Clinical School, Faculty of Medicine, UNSW Sydney, Kensington, NSW, 2052, Australia; Cancer Care Centre, St. George Hospital, Kogarah, NSW, 2217, Australia; School of Basic Medicine, Zhengzhou University, Zhengzhou, 450001, China.
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An Overview of Nrf2 Signaling Pathway and Its Role in Inflammation. Molecules 2020; 25:molecules25225474. [PMID: 33238435 PMCID: PMC7700122 DOI: 10.3390/molecules25225474] [Citation(s) in RCA: 573] [Impact Index Per Article: 143.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/13/2020] [Accepted: 11/19/2020] [Indexed: 12/16/2022] Open
Abstract
Inflammation is a key driver in many pathological conditions such as allergy, cancer, Alzheimer’s disease, and many others, and the current state of available drugs prompted researchers to explore new therapeutic targets. In this context, accumulating evidence indicates that the transcription factor Nrf2 plays a pivotal role controlling the expression of antioxidant genes that ultimately exert anti-inflammatory functions. Nrf2 and its principal negative regulator, the E3 ligase adaptor Kelch-like ECH- associated protein 1 (Keap1), play a central role in the maintenance of intracellular redox homeostasis and regulation of inflammation. Interestingly, Nrf2 is proved to contribute to the regulation of the heme oxygenase-1 (HO-1) axis, which is a potent anti-inflammatory target. Recent studies showed a connection between the Nrf2/antioxidant response element (ARE) system and the expression of inflammatory mediators, NF-κB pathway and macrophage metabolism. This suggests a new strategy for designing chemical agents as modulators of Nrf2 dependent pathways to target the immune response. Therefore, the present review will examine the relationship between Nrf2 signaling and the inflammation as well as possible approaches for the therapeutic modulation of this pathway.
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Zaki SM, Algaleel WAA, Imam RA, Soliman GF, Ghoneim FM. Nano-curcumin versus curcumin in amelioration of deltamethrin-induced hippocampal damage. Histochem Cell Biol 2020; 154:157-175. [PMID: 32227291 DOI: 10.1007/s00418-020-01871-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/10/2020] [Indexed: 12/16/2022]
Abstract
We aimed to prove that oxidative stress is the main mechanism responsible for hippocampal neurotoxicity induced by deltamethrin (DLM). The protective role of curcumin (CMN) and nano-curcumin (NCMN) over this toxicity was studied. The rats were categorized into four groups: control, DLM, CMN and NCMN. The study continued for 30 days. Hippocampus was processed for histological, biochemical and immunohistochemical studies. Caspase-3, glial fibrillar acidic protein (GFAP), acetylcholinesterase (AChE), malondialdehyde (MDA), glutathione (GSH), catalase (CAT) and superoxide dismutase (SOD) were measured for DLM-induced oxidative stress (increased MDA by 354%/decreased GSH by 61%, SOD by 61%, CAT 57%). Oxidative stress induced apoptosis of hippocampal neurons through increasing Nrf2, gamma-glutamyl cysteine synthetase heavy subunit (GCS-HS) and light subunit (GCS-LS) and decreasing AChE. It increases the activity of astrocytes through increasing GFAP. Finally, oxidative stress has a bad impaction on cognitive function. Improvement of oxidative stress was observed with use of CMN and NCMN (decrease of MDA/increase of GSH, SOD, CAT). The level of Nrf2, GCS-HS and GCS-LS decreased, while AChE, GFAP increased. Improvement of cognitive function was observed in both groups. In conclusion, oxidative stress is the common mechanism responsible for DLM-induced hippocampal neurotoxicity. It exerts apoptosis of hippocampal neurons through increasing Nrf2, HS-GCS, LS-GCS and decreasing AChE. In addition, it activates astrocytes through increasing expression of GFAP. The protective role of CMN and CMMN is related to their potent antioxidant effect. Much improvement has been detected with NCMN as compared to CMN.
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Affiliation(s)
- Sherif Mohamed Zaki
- Department of Anatomy and Embryology, Faculty of Medicine, Cairo University, Giza, Egypt. .,Fakeeh College for Medical Sciences, Jeddah, Saudi Arabia.
| | - Waleed Ahmed Abd Algaleel
- Department of Anatomy and Embryology, Faculty of Medicine, Cairo University, Giza, Egypt.,Faculty of Medicine, Cairo University, Giza, Egypt
| | - Reda Abdelnasser Imam
- Department of Anatomy and Embryology, Faculty of Medicine, Cairo University, Giza, Egypt.,Faculty of Medicine, Cairo University, Giza, Egypt
| | - Ghada F Soliman
- Department of Pharmacology, Faculty of Medicine, Cairo University, Giza, Egypt.,Faculty of Medicine, Cairo University, Giza, Egypt
| | - Fatma M Ghoneim
- Department of Histology and Cell Biology, Faculty of Medicine, Mansoura University, Mansoura, Egypt.,Faculty of Medicine, Mansoura University, Mansoura, Egypt
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Liu JD, Liu WB, Zhang CY, Xu CY, Zheng XC, Zhang DD, Chi C. Dietary glutathione supplementation enhances antioxidant activity and protects against lipopolysaccharide-induced acute hepatopancreatic injury and cell apoptosis in Chinese mitten crab, Eriocheir sinensis. FISH & SHELLFISH IMMUNOLOGY 2020; 97:440-454. [PMID: 31857224 DOI: 10.1016/j.fsi.2019.12.049] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 12/13/2019] [Accepted: 12/15/2019] [Indexed: 06/10/2023]
Abstract
Eriocheir sinensis (E. sinensis) is an important aquaculture species in China. However, deteriorating water environments lead to oxidative stress in these crabs, which subsequently reduces their quality and yield. Glutathione (GSH) is an endogenous antioxidant that is used to mitigate oxidative stress. However, whether dietary GSH can enhance the resistance of E. sinensis to oxidative stress remains unclear. Herein, crabs were fed dietary GSH (the basal diet was supplemented with 0, 300, 600, 900, and 1200 mg/kg diet weight of GSH) for up to 3 weeks and, then, challenged with lipopolysaccharide (LPS; 400 μg/kg body weight). After 6 h, their hepatopancreas were sampled. Diet supplementation with 600 and 900 mg/kg diet weight GSH not only increased the content of GSH in the hepatopancreas, but also enhanced the activities and mRNA expressions of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione-S-transferase (GST) (P < 0.05), compared to that in control crabs challenged with LPS alone. Diet supplementation with 600 or 900 mg/kg GSH also significantly increased the enzyme activities of GSH reductase and γ-glutamyl cysteine synthetase (γ-GCS) in LPS-treated crabs. Haematoxylin-eosin (HE) staining, electron microscopy, and flow cytometry were used to examine the structure and subcellular structure of and apoptosis in the hepatopancreas. The histopathology and sub-microstructure analysis results also showed that diet supplementation with 600 or 900 mg/kg GSH significantly alleviated damage in crabs challenged with LPS and decreased reactive oxygen species (ROS) levels and cell apoptosis ratios in the hepatopancreas, compared to the LPS-treated crabs. To further understand the effect of dietary GSH on LPS-induced apoptosis, the activities and gene or protein expressions of apoptosis-related factors were evaluated. As a result, diet supplementation with 600 or 900 mg/kg GSH significantly decreased the activities of caspases-3, -8, and -9 and inhibited the relative expression of caspase-3 and -8 but increased the expression of B-cell lymphoma-2 (bcl-2) and B-cell lymphoma-2-associated X inhibitor (bax inhibitor) in crabs challenged with LPS. This treatment further significantly downregulated the relative protein levels of caspase-3, -8, -9 and Bax and upregulated those of Bcl-2 in crabs challenged with LPS. However, treatment with 1200 mg/kg GSH caused the opposite effects. Overall, our results reveal that appropriate diets supplemented with 600 or 900 mg/kg GSH could enhance the antioxidant capacity and anti-apoptotic mechanisms in crabs after LPS injection, thereby providing a theoretical basis for the application of dietary GSH in E. sinensis.
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Affiliation(s)
- Jia-Dai Liu
- Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, National Experimental Teaching Center for Animal Science, College of Animal Science and Technology, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing, 210095, Jiangsu Province, People's Republic of China
| | - Wen-Bin Liu
- Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, National Experimental Teaching Center for Animal Science, College of Animal Science and Technology, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing, 210095, Jiangsu Province, People's Republic of China
| | - Cai-Yan Zhang
- Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, National Experimental Teaching Center for Animal Science, College of Animal Science and Technology, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing, 210095, Jiangsu Province, People's Republic of China
| | - Chen-Yuan Xu
- Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, National Experimental Teaching Center for Animal Science, College of Animal Science and Technology, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing, 210095, Jiangsu Province, People's Republic of China
| | - Xiao-Chuan Zheng
- Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, National Experimental Teaching Center for Animal Science, College of Animal Science and Technology, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing, 210095, Jiangsu Province, People's Republic of China
| | - Ding-Dong Zhang
- Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, National Experimental Teaching Center for Animal Science, College of Animal Science and Technology, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing, 210095, Jiangsu Province, People's Republic of China
| | - Cheng Chi
- Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, National Experimental Teaching Center for Animal Science, College of Animal Science and Technology, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing, 210095, Jiangsu Province, People's Republic of China.
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Rajagopalan P, Jain AP, Nanjappa V, Patel K, Mangalaparthi KK, Babu N, Cavusoglu N, Roy N, Soeur J, Breton L, Pandey A, Gowda H, Chatterjee A, Misra N. Proteome-wide changes in primary skin keratinocytes exposed to diesel particulate extract—A role for antioxidants in skin health. J Dermatol Sci 2019; 96:114-124. [DOI: 10.1016/j.jdermsci.2019.08.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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8
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Rajagopalan P, Jain AP, Nanjappa V, Patel K, Mangalaparthi KK, Babu N, Cavusoglu N, Roy N, Soeur J, Breton L, Pandey A, Gowda H, Chatterjee A, Misra N. Proteome-wide changes in primary skin keratinocytes exposed to diesel particulate extract-A role for antioxidants in skin health. J Dermatol Sci 2018; 91:239-249. [PMID: 29857962 DOI: 10.1016/j.jdermsci.2018.05.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 04/02/2018] [Accepted: 05/01/2018] [Indexed: 12/19/2022]
Abstract
BACKGROUND Skin acts as a protective barrier against direct contact with pollutants but inhalation and systemic exposure have indirect effect on keratinocytes. Exposure to diesel exhaust has been linked to increased oxidative stress. OBJECTIVE To investigate global proteomic alterations in diesel particulate extract (DPE)/its vapor exposed skin keratinocytes. METHODS We employed Tandem Mass Tag (TMT)-based proteomics to study effect of DPE/DPE vapor on primary skin keratinocytes. RESULTS We observed an increased expression of oxidative stress response protein NRF2, upon chronic exposure of primary keratinocytes to DPE/its vapor which includes volatile components such as polycyclic aromatic hydrocarbons (PAHs). Mass spectrometry-based quantitative proteomics led to identification 4490 proteins of which 201 and 374 proteins were significantly dysregulated (≥1.5 fold, p≤0.05) in each condition, respectively. Proteins involved in cellular processes such as cornification (cornifin A), wound healing (antileukoproteinase) and differentiation (suprabasin) were significantly downregulated in primary keratinocytes exposed to DPE/DPE vapor. These results were corroborated in 3D skin models chronically exposed to DPE/DPE vapor. Bioinformatics analyses indicate that DPE and its vapor affect distinct molecular processes in skin keratinocytes. Components of mitochondrial oxidative phosphorylation machinery were seen to be exclusively overexpressed upon chronic DPE vapor exposure. In addition, treatment with an antioxidant like vitamin E partially restores expression of proteins altered upon exposure to DPE/DPE vapor. CONCLUSIONS Our study highlights distinct adverse effects of chronic exposure to DPE/DPE vapor on skin keratinocytes and the potential role of vitamin E in alleviating adverse effects of environmental pollution.
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Affiliation(s)
| | - Ankit P Jain
- Institute of Bioinformatics, International Tech Park, Bangalore 560066, India.
| | | | - Krishna Patel
- Institute of Bioinformatics, International Tech Park, Bangalore 560066, India.
| | | | - Niraj Babu
- Institute of Bioinformatics, International Tech Park, Bangalore 560066, India; Manipal Academy of Higher Education (MAHE), Manipal 576104, Karnataka, India.
| | - Nükhet Cavusoglu
- L'Oréal Research and Innovation, Aulnay sous bois, 93600, France.
| | - Nita Roy
- L'Oréal India Pvt. Ltd., Beary's Global Research Triangle, Bangalore 560067, India.
| | - Jeremie Soeur
- L'Oréal Research and Innovation, Aulnay sous bois, 93600, France.
| | - Lionel Breton
- L'Oréal Research and Innovation, Aulnay sous bois, 93600, France.
| | - Akhilesh Pandey
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA; Departments of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA; Departments of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA; Departments of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | - Harsha Gowda
- Institute of Bioinformatics, International Tech Park, Bangalore 560066, India.
| | - Aditi Chatterjee
- Institute of Bioinformatics, International Tech Park, Bangalore 560066, India.
| | - Namita Misra
- L'Oréal Research and Innovation, Aulnay sous bois, 93600, France; L'Oréal India Pvt. Ltd., Beary's Global Research Triangle, Bangalore 560067, India.
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Mondal NK, Saha H, Mukherjee B, Tyagi N, Ray MR. Inflammation, oxidative stress, and higher expression levels of Nrf2 and NQO1 proteins in the airways of women chronically exposed to biomass fuel smoke. Mol Cell Biochem 2018; 447:63-76. [DOI: 10.1007/s11010-018-3293-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Accepted: 01/19/2018] [Indexed: 11/24/2022]
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10
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Zhang H, Liu H, Zhou L, Yuen J, Forman HJ. Temporal changes in glutathione biosynthesis during the lipopolysaccharide-induced inflammatory response of THP-1 macrophages. Free Radic Biol Med 2017; 113:304-310. [PMID: 28993271 PMCID: PMC5699958 DOI: 10.1016/j.freeradbiomed.2017.10.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 09/11/2017] [Accepted: 10/06/2017] [Indexed: 11/30/2022]
Abstract
How macrophages maintain redox homeostasis in the inflammatory process, in which a large amount of oxidants are produced, remains elusive. In this study, we investigated the temporal changes in the intracellular glutathione (GSH), the master antioxidant, and the expression of glutamate cysteine ligase (GCL), the rate-limiting enzyme for GSH biosynthesis, in the inflammatory response of human macrophages (THP1 cells) to lipopolysaccharide. Intracellular GSH concentration was decreased significantly in the early phase (~6h) of LPS exposure, and then gradually went back to the basal level in the late phase (9-24h). The expression level of the catalytic subunit of GCL (GCLC) followed a similar pattern of change as GSH: its mRNA and protein levels were reduced in the early phase and then back to basal level in the late phase. In contrast, the expression of the modifier subunit of GCL (GCLM) was significantly increased in the phase of LPS exposure. Activation Nrf2, the transcription factor involved in the induction of both GCLC and GCLM, occurred at as early as 3h after LPS exposure; whereas the activation of NF-κB occurred at as early as 30min. Inhibition of NF-κB signaling with SN50 prevented the decrease of GCLC and inhibited Nrf2 activation in response to LPS. These data demonstrate time-dependent changes in the expression of GCL and Nrf2 signaling during the inflammatory response, and that the regulation of GCLC and GCLM might be through different pathways in this process.
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Affiliation(s)
- Hongqiao Zhang
- Andrus Gerontology Center of the Leonard Davis School of Gerontology, University of Southern California, 3715 McClintock Ave, GER306B, Los Angeles, CA 90089-0191, USA.
| | - Honglei Liu
- Children's Hospital Los Angeles, 4650 Sunset Blvd, Los Angeles, CA 90027, USA
| | - Lulu Zhou
- Andrus Gerontology Center of the Leonard Davis School of Gerontology, University of Southern California, 3715 McClintock Ave, GER306B, Los Angeles, CA 90089-0191, USA
| | - Jenay Yuen
- Andrus Gerontology Center of the Leonard Davis School of Gerontology, University of Southern California, 3715 McClintock Ave, GER306B, Los Angeles, CA 90089-0191, USA
| | - Henry Jay Forman
- Andrus Gerontology Center of the Leonard Davis School of Gerontology, University of Southern California, 3715 McClintock Ave, GER306B, Los Angeles, CA 90089-0191, USA
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Macias-Barragan J, Huerta-Olvera SG, Hernandez-Cañaveral I, Pereira-Suarez AL, Montoya-Buelna M. Cadmium and α-lipoic acid activate similar de novo synthesis and recycling pathways for glutathione balance. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2017; 52:38-46. [PMID: 28366867 DOI: 10.1016/j.etap.2017.03.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 03/06/2017] [Accepted: 03/07/2017] [Indexed: 06/07/2023]
Abstract
Glutathione (GSH) protects cells against oxidative stress. Redox modifiers induce GSH biosynthesis and recycling to maintain reduced environment inside cells. Cadmium (Cd2+) is a heavy metal that activates redox-sensitive transcriptional factors. The antioxidant α-lipoic acid (ALA) has shown to modulate GSH pathways. This study aimed to investigate de novo synthesis and recycling pathways for GSH balance by different Cd2+ concentrations and ALA in HepG2 cells. ALA activates Nrf2 pathway leading to GSH increment. Pre-treatment with 1μM Cd2+ or ALA produces tolerance to 5μM Cd2+ toxic effects. 5μM Cd2+ exposure significantly augmented nuclear Nrf2, GSH and GCLC, GCLM, HMOX1, TNFα and IL-6 mRNA expression but not GSR, however these upsurges were significantly abrogated by ALA or 1μM Cd2+ pre-treatments. Exposure to low Cd2+ concentration generate timely protective responses, similar to that elicited by ALA, maintaining a normal redox balance inside the cell due to GSH replenishment.
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Affiliation(s)
- Jose Macias-Barragan
- Department of Health Sciences, CUValles, University of Guadalajara, Guadalajara - Ameca Rd Km. 45.5, Ameca, Jalisco, 46600, Mexico; Laboratory of Immunology, Department of Physiology, CUCS, University of Guadalajara, 950 Sierra Mojada St., Guadalajara, Jalisco, 44340, Mexico.
| | - Selene G Huerta-Olvera
- Department of Medical and Life Sciences, CUCienega, University of Guadalajara, 1115 Universidad Ave., Ocotlán, Jalisco, 47820, Mexico
| | - Ivan Hernandez-Cañaveral
- Department of Microbiology and Pathology, CUCS, University of Guadalajara, 950 Sierra Mojada St., Guadalajara, Jalisco, 44340, Mexico
| | - Ana Laura Pereira-Suarez
- Laboratory of Immunology, Department of Physiology, CUCS, University of Guadalajara, 950 Sierra Mojada St., Guadalajara, Jalisco, 44340, Mexico
| | - Margarita Montoya-Buelna
- Laboratory of Immunology, Department of Physiology, CUCS, University of Guadalajara, 950 Sierra Mojada St., Guadalajara, Jalisco, 44340, Mexico
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12
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Kawakami K, Moritani C, Uraji M, Fujita A, Kawakami K, Hatanaka T, Suzaki E, Tsuboi S. Hepatoprotective effects of rice-derived peptides against acetaminophen-induced damage in mice. J Clin Biochem Nutr 2016; 60:115-120. [PMID: 28366990 PMCID: PMC5370527 DOI: 10.3164/jcbn.16-44] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 08/18/2016] [Indexed: 12/14/2022] Open
Abstract
Glutathione, the most abundant intracellular antioxidant, protects cells against reactive oxygen species induced oxidative stress and regulates intracellular redox status. We found that rice peptides increased intracellular glutathione levels in human hepatoblastoma HepG2 cells. Acetaminophen is a commonly used analgesic. However, an overdose of acetaminophen causes severe hepatotoxicity via depletion of hepatic glutathione. Here, we investigated the protective effects of rice peptides on acetaminophen-induced hepatotoxicity in mice. ICR mice were orally administered rice peptides (0, 100 or 500 mg/kg) for seven days, followed by the induction of hepatotoxicity via intraperitoneal injection of acetaminophen (700 mg/kg). Pretreatment with rice peptides significantly prevented increases in serum alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase levels and protected against hepatic glutathione depletion. The expression of γ-glutamylcysteine synthetase, a key regulatory enzyme in the synthesis of glutathione, was decreased by treatment with acetaminophen, albeit rice peptides treatment recovered its expression compared to that achieved treatment with acetaminophen. In addition, histopathological evaluation of the livers also revealed that rice peptides prevented acetaminophen-induced centrilobular necrosis. These results suggest that rice peptides increased intracellular glutathione levels and could protect against acetaminophen-induced hepatotoxicity in mice.
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Affiliation(s)
- Kayoko Kawakami
- School of Pharmacy, Shujitsu University, 1-6-1 Nishigawara, Naka-Ku, Okayama 703-8516, Japan
| | - Chie Moritani
- School of Pharmacy, Shujitsu University, 1-6-1 Nishigawara, Naka-Ku, Okayama 703-8516, Japan
| | - Misugi Uraji
- Okayama Prefectural Technology Canter for Agriculture, Forestry and Fisheries, Research Institute for Biological Sciences (RIBS), Okayama, 7549-1 Kibichuo-cho, Kaga-gun, Okayama 716-1241, Japan
| | - Akiko Fujita
- SATAKE Corporation, 2-30 Saijo Nishihonmachi, Higashi-Hiroshima-shi, Hiroshima 739-8602, Japan
| | - Koji Kawakami
- SATAKE Corporation, 2-30 Saijo Nishihonmachi, Higashi-Hiroshima-shi, Hiroshima 739-8602, Japan
| | - Tadashi Hatanaka
- Okayama Prefectural Technology Canter for Agriculture, Forestry and Fisheries, Research Institute for Biological Sciences (RIBS), Okayama, 7549-1 Kibichuo-cho, Kaga-gun, Okayama 716-1241, Japan
| | - Etsuko Suzaki
- School of Pharmacy, Shujitsu University, 1-6-1 Nishigawara, Naka-Ku, Okayama 703-8516, Japan
| | - Seiji Tsuboi
- School of Pharmacy, Shujitsu University, 1-6-1 Nishigawara, Naka-Ku, Okayama 703-8516, Japan
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13
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Molecular and cellular basis for the unique functioning of Nrf1, an indispensable transcription factor for maintaining cell homoeostasis and organ integrity. Biochem J 2016; 473:961-1000. [PMID: 27060105 DOI: 10.1042/bj20151182] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 01/26/2016] [Indexed: 12/30/2022]
Abstract
The consensuscis-regulatory AP-1 (activator protein-1)-like AREs (antioxidant-response elements) and/or EpREs (electrophile-response elements) allow for differential recruitment of Nrf1 [NF-E2 (nuclear factor-erythroid 2)-related factor 1], Nrf2 and Nrf3, together with each of their heterodimeric partners (e.g. sMaf, c-Jun, JunD or c-Fos), to regulate different sets of cognate genes. Among them, NF-E2 p45 and Nrf3 are subject to tissue-specific expression in haemopoietic and placental cell lineages respectively. By contrast, Nrf1 and Nrf2 are two important transcription factors expressed ubiquitously in various vertebrate tissues and hence may elicit putative combinational or competitive functions. Nevertheless, they have de facto distinct biological activities because knockout of their genes in mice leads to distinguishable phenotypes. Of note, Nrf2 is dispensable during development and growth, albeit it is accepted as a master regulator of antioxidant, detoxification and cytoprotective genes against cellular stress. Relative to the water-soluble Nrf2, less attention has hitherto been drawn to the membrane-bound Nrf1, even though it has been shown to be indispensable for embryonic development and organ integrity. The biological discrepancy between Nrf1 and Nrf2 is determined by differences in both their primary structures and topovectorial subcellular locations, in which they are subjected to distinct post-translational processing so as to mediate differential expression of ARE-driven cytoprotective genes. In the present review, we focus on the molecular and cellular basis for Nrf1 and its isoforms, which together exert its essential functions for maintaining cellular homoeostasis, normal organ development and growth during life processes. Conversely, dysfunction of Nrf1 results in spontaneous development of non-alcoholic steatohepatitis, hepatoma, diabetes and neurodegenerative diseases in animal models.
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14
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Glutamate cysteine ligase and the age-related decline in cellular glutathione: The therapeutic potential of γ-glutamylcysteine. Arch Biochem Biophys 2016; 593:12-23. [DOI: 10.1016/j.abb.2016.01.017] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 01/27/2016] [Accepted: 01/28/2016] [Indexed: 01/28/2023]
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15
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Preda MB, Rønningen T, Burlacu A, Simionescu M, Moskaug JØ, Valen G. Remote transplantation of mesenchymal stem cells protects the heart against ischemia-reperfusion injury. Stem Cells 2015; 32:2123-34. [PMID: 24578312 DOI: 10.1002/stem.1687] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 02/01/2014] [Indexed: 12/15/2022]
Abstract
Cardioprotection can be evoked through extracardiac approaches. This prompted us to investigate whether remote transplantation of stem cells confers protection of the heart against ischemic injury. The cardioprotective effect of subcutaneous transplantation of naïve versus heme oxygenase-1 (HMOX-1)-overexpressing mouse mesenchymal stem cells (MSC) to mice was investigated in hearts subjected to ischemia-reperfusion in a Langendorff perfusion system. Mice were transplanted into the interscapular region with naïve or HMOX-1 transfected MSC isolated from transgenic luciferase reporter mice and compared to sham-treated animals. The fate of transplanted cells was followed by in vivo bioluminescence imaging, revealing that MSC proliferated, but did not migrate detectably from the injection site. Ex vivo analysis of the hearts showed that remote transplantation of mouse adipose-derived MSC (mASC) resulted in smaller infarcts and improved cardiac function after ischemia-reperfusion compared to sham-treated mice. Although HMOX-1 overexpression conferred cytoprotective effects on mASC against oxidative stress in vitro, no additive beneficial effect of HMOX-1 transfection was noted on the ischemic heart. Subcutaneous transplantation of MSC also improved left ventricular function when transplanted in vivo after myocardial infarction. Plasma analysis and gene expression profile of naïve- and HMOX-1-mASC after transplantation pointed toward pentraxin 3 as a possible factor involved in the remote cardioprotective effect of mASC. These results have significant implications for understanding the behavior of stem cells after transplantation and development of safe and noninvasive cellular therapies with clinical applications. Remote transplantation of MSC can be considered as an alternative procedure to induce cardioprotection.
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Affiliation(s)
- Mihai Bogdan Preda
- Institute of Cellular Biology and Pathology "Nicolae Simionescu" of the Romanian Academy, Bucharest, Romania; Department of Biochemistry, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway; Department of Physiology, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway
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16
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Katakami N, Kaneto H, Matsuoka TA, Takahara M, Osonoi T, Saitou M, Kawai K, Ishibashi F, Kashiwagi A, Kawamori R, Shimomura I, Yamasaki Y. Accumulation of oxidative stress-related gene polymorphisms and the risk of coronary heart disease events in patients with type 2 diabetes--an 8-year prospective study. Atherosclerosis 2014; 235:408-14. [PMID: 24933031 DOI: 10.1016/j.atherosclerosis.2014.05.936] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 05/19/2014] [Accepted: 05/21/2014] [Indexed: 01/22/2023]
Abstract
OBJECTIVE Oxidative stress, which is provoked in patients with diabetes, plays critical roles in the pathogenesis of coronary heart disease (CHD). We simultaneously determined 5 relatively common genetic variants related to oxidative stress and evaluated the combined effect on CHD. METHODS We enrolled 1977 Japanese type 2 diabetic subjects without history of CVD (males 66.1%, 59.5 ± 10.0 years old), determined their genotypes regarding glutamate-cysteine ligase modifier subunit (GCLM) C-588T, manganese superoxide dismutase (SOD2) Val16Ala, endothelial nitric oxide synthase (NOS3) G894T, NAD(P)H oxidase p22phox (CYBA) C242T, and myeloperoxidase (MPO) G-463A polymorphisms, and prospectively evaluated the association between these polymorphisms and CHD events. RESULTS The median follow-up period was 7.5 years and there were 85 new CHD events. The single association analysis revealed that there were no statistically significant associations between each polymorphism and the prevalence of CHD. Interestingly, the risk of CHD event was higher with the increase of the total number of 10 concomitant unfavorable "pro-oxidant alleles" in each subject (p for trend = 0.018, log-rank test). Especially, the carriers of ≥8 pro-oxidant alleles had a significantly increased risk as compared to the carriers of <8 pro-oxidant alleles, whether the other clinical variables were adjusted (HR 2.92 with 95%CI 1.50-5.67, p = 0.002) or not (HR 2.89 with 95%CI 1.49-5.59, p = 0.002).. CONCLUSIONS Accumulation of gene polymorphisms related to oxidative stress is likely associated with the development of CHD in patients with type 2 diabetes, suggesting that the combined information about these variants is useful to assess the risk of CHD.
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Affiliation(s)
- Naoto Katakami
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Japan; Department of Metabolism and Atherosclerosis, Osaka University Graduate School of Medicine, Japan.
| | - Hideaki Kaneto
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Japan
| | - Taka-Aki Matsuoka
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Japan
| | - Mitsuyoshi Takahara
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Japan
| | | | | | | | | | | | - Ryuzo Kawamori
- Sportology Center, Juntendo University School of Medicine, Japan
| | - Iichiro Shimomura
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Japan
| | - Yoshimitsu Yamasaki
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Japan
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17
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Curcumin eliminates the effect of advanced glycation end-products (AGEs) on the divergent regulation of gene expression of receptors of AGEs by interrupting leptin signaling. J Transl Med 2014; 94:503-16. [PMID: 24614199 PMCID: PMC4006284 DOI: 10.1038/labinvest.2014.42] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 01/03/2014] [Accepted: 01/15/2014] [Indexed: 12/30/2022] Open
Abstract
Non-alcoholic steatohepatitis (NASH) is a major risk factor for hepatic fibrogenesis. NASH is often found in diabetic patients with hyperglycemia. Hyperglycemia induces non-enzymatic glycation of proteins, yielding advanced glycation end-products (AGEs). Effects of AGEs are mainly mediated by two categories of cytoplasmic membrane receptors. Receptor for AGEs (RAGE) is associated with increased oxidative stress and inflammation, whereas AGE receptor-1 (AGE-R1) is involved in detoxification and clearance of AGEs. Activation of hepatic stellate cells (HSC) is crucial to the development of hepatic fibrosis. We recently reported that AGEs stimulated HSC activation likely by inhibiting gene expression of AGE-R1 and inducing gene expression of RAGE in HSC, which were eliminated by the antioxidant curcumin. This study is to test our hypothesis that curcumin eliminates the effects of AGEs on the divergent regulation of the two receptors of AGEs in HSC by interrupting the AGE-caused activation of leptin signaling, leading to the inhibition of HSC activation. We observed herein that AGEs activated leptin signaling by inducing gene expression of leptin and its receptor in HSC. Like AGEs, leptin differentially regulated gene expression of RAGE and AGE-R1. Curcumin eliminated the effects of AGEs in HSC by interrupting leptin signaling and activating transcription factor NF-E2 p45-related factor 2 (Nrf2), leading to the elevation of cellular glutathione and the attenuation of oxidative stress. In conclusions, curcumin eliminated the effects of AGEs on the divergent regulation of gene expression of RAGE and AGE-R1 in HSC by interrupting the AGE-caused activation of leptin signaling, leading to the inhibition of HSC activation.
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18
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Quindry JC, Hamilton KL. Exercise and cardiac preconditioning against ischemia reperfusion injury. Curr Cardiol Rev 2014; 9:220-9. [PMID: 23909636 PMCID: PMC3780347 DOI: 10.2174/1573403x113099990033] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2012] [Accepted: 06/02/2013] [Indexed: 12/30/2022] Open
Abstract
Cardiovascular disease (CVD), including ischemia reperfusion (IR) injury, remains a major cause of morbidity and mortality in industrialized nations. Ongoing research is aimed at uncovering therapeutic interventions against IR injury. Regular exercise participation is recognized as an important lifestyle intervention in the prevention and treatment of CVD and IR injury. More recent understanding reveals that moderate intensity aerobic exercise is also an important experimental model for understanding the cellular mechanisms of cardioprotection against IR injury. An important discovery in this regard was the observation that one-to-several days of exercise will attenuate IR injury. This phenomenon has been observed in young and old hearts of both sexes. Due to the short time course of exercise induced protection, IR injury prevention must be mediated by acute biochemical alterations within the myocardium. Research over the last decade reveals that redundant mechanisms account for exercise induced cardioprotection against IR. While much is now known about exercise preconditioning against IR injury, many questions remain. Perhaps most pressing, is what mechanisms mediate cardioprotection in aged hearts and what sex-dependent differences exist. Given that that exercise preconditioning is a polygenic effect, it is likely that multiple mediators of exercise induced cardioprotection have yet to be uncovered. Also unknown, is whether post translational modifications due to exercise are responsible for IR injury prevention. This review will provide an overview the major mechanisms of IR injury and exercise preconditioning. The discussion highlights many promising avenues for further research and describes how exercise preconditioning may continue to be an important scientific paradigm in the translation of cardioprotection research to the clinic.
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Affiliation(s)
- John C Quindry
- Cardioprotection Laboratory, Department of Kinesiology, Auburn University, AL 36849, USA
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19
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Forman HJ, Davies KJA, Ursini F. How do nutritional antioxidants really work: nucleophilic tone and para-hormesis versus free radical scavenging in vivo. Free Radic Biol Med 2014; 66:24-35. [PMID: 23747930 PMCID: PMC3852196 DOI: 10.1016/j.freeradbiomed.2013.05.045] [Citation(s) in RCA: 487] [Impact Index Per Article: 48.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 05/29/2013] [Accepted: 05/30/2013] [Indexed: 02/07/2023]
Abstract
We present arguments for an evolution in our understanding of how antioxidants in fruits and vegetables exert their health-protective effects. There is much epidemiological evidence for disease prevention by dietary antioxidants and chemical evidence that such compounds react in one-electron reactions with free radicals in vitro. Nonetheless, kinetic constraints indicate that in vivo scavenging of radicals is ineffective in antioxidant defense. Instead, enzymatic removal of nonradical electrophiles, such as hydroperoxides, in two-electron redox reactions is the major antioxidant mechanism. Furthermore, we propose that a major mechanism of action for nutritional antioxidants is the paradoxical oxidative activation of the Nrf2 (NF-E2-related factor 2) signaling pathway, which maintains protective oxidoreductases and their nucleophilic substrates. This maintenance of "nucleophilic tone," by a mechanism that can be called "para-hormesis," provides a means for regulating physiological nontoxic concentrations of the nonradical oxidant electrophiles that boost antioxidant enzymes, and damage removal and repair systems (for proteins, lipids, and DNA), at the optimal levels consistent with good health.
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Affiliation(s)
- Henry J Forman
- University of California, Merced, 5200 North Lake Road, Merced, CA 95343, USA; Andrus Gerontology Center of the Davis School of Gerontology, University of Southern, California, 3715 McClintock Avenue, Los Angeles, CA 90089-0191, USA
| | - Kelvin J A Davies
- Andrus Gerontology Center of the Davis School of Gerontology, University of Southern, California, 3715 McClintock Avenue, Los Angeles, CA 90089-0191, USA; Division of Molecular & Computational Biology, Department of Biological Sciences, Dornsife College of Letters, Arts, and Sciences, University of Southern California, 3715 McClintock Avenue, Los Angeles, CA 90089-0191, USA
| | - Fulvio Ursini
- Department of Molecular Medicine, University of Padova, Viale G. Colombo 3, I-35121, Padova, Italy.
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20
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Qaisiya M, Coda Zabetta CD, Bellarosa C, Tiribelli C. Bilirubin mediated oxidative stress involves antioxidant response activation via Nrf2 pathway. Cell Signal 2013; 26:512-20. [PMID: 24308969 DOI: 10.1016/j.cellsig.2013.11.029] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 11/21/2013] [Accepted: 11/26/2013] [Indexed: 12/22/2022]
Abstract
Unconjugated bilirubin (UCB) is responsible for neonatal jaundice and high level of free bilirubin (Bf) can lead to kernicterus. Previous studies suggest that oxidative stress is a critical component of UCB-induced neurotoxicity. The Nrf2 pathway is a powerful sensor for cellular redox state and is activated directly by oxidative stress and/or indirectly by stress response protein kinases. Activated Nrf2 translocates to nucleus, binds to Antioxidant Response Element (ARE), and enhances the up-regulation of cytoprotective genes that mediate cell survival. The aim of the present study was to investigate the role of Nrf2 pathway in cell response to bilirubin mediated oxidative stress in the neuroblastoma SH-SY5Y cell line. Cells exposed to a toxic concentration of UCB (140 nM Bf) showed an increased intracellular ROS levels and enhanced nuclear accumulation of Nrf2 protein. UCB stimulated transcriptional induction of ARE-GFP reporter gene and induced mRNA expression of multiple antioxidant response genes as: xCT, Gly1, γGCL-m, γGCL-c, HO-1, NQO1, FTH, ME1, and ATF3. Nrf2 siRNA decreased UCB induced mRNA expression of HO1 (75%), NQO1 (54%), and FTH (40%). The Nrf2-related HO-1 induction was reduced to 60% in cells pre-treated with antioxidant (NAC) or specific signaling pathway inhibitors for PKC, P38α and MEK1/2 (80, 40 and 25%, respectively). In conclusion, we demonstrated that SH-SY5Y cells undergo an adaptive response against UCB-mediated oxidative stress by activation of multiple antioxidant response, in part through Nrf2 pathway.
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Affiliation(s)
- Mohammed Qaisiya
- Fondazione Italiana Fegato ONLUS, Italian Liver Foundation ONLUS, Bldg Q AREA Science Park - Basovizza Campus, 34149 Trieste, Italy.
| | - Carlos Daniel Coda Zabetta
- Fondazione Italiana Fegato ONLUS, Italian Liver Foundation ONLUS, Bldg Q AREA Science Park - Basovizza Campus, 34149 Trieste, Italy.
| | - Cristina Bellarosa
- Fondazione Italiana Fegato ONLUS, Italian Liver Foundation ONLUS, Bldg Q AREA Science Park - Basovizza Campus, 34149 Trieste, Italy.
| | - Claudio Tiribelli
- Fondazione Italiana Fegato ONLUS, Italian Liver Foundation ONLUS, Bldg Q AREA Science Park - Basovizza Campus, 34149 Trieste, Italy; Department of Medical Sciences, University of Trieste, 34100 Trieste, Italy.
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Ji L, Li H, Gao P, Shang G, Zhang DD, Zhang N, Jiang T. Nrf2 pathway regulates multidrug-resistance-associated protein 1 in small cell lung cancer. PLoS One 2013; 8:e63404. [PMID: 23667609 PMCID: PMC3646742 DOI: 10.1371/journal.pone.0063404] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Accepted: 04/02/2013] [Indexed: 12/02/2022] Open
Abstract
Although multidrug-resistance-associated protein-1 (MRP1) is a major contributor to multi-drug resistance (MDR), the regulatory mechanism of Mrp1 still remains unclear. Nrf2 is a transcription factor that regulates cellular defense response through antioxidant response elements (AREs) in normal tissues. Recently, Nrf2 has emerged as an important contributor to chemo-resistance in tumor tissues. In the present study, the role of Nrf2-ARE pathway on regulation of Mrp1 was investigated. Compared with H69 lung cancer cells, H69AR cells with MDR showed significantly higher Nrf2-ARE pathway activity and expression of Mrp1 as well. When Nrf2 was knocked down in H69AR cells, MRP1's expression decreased accordingly. Moreover, those H69AR cells with reduced Nrf2 level restored sensitivity to chemo-drugs. To explore how Nrf2-ARE pathway regulates Mrp1, the promoter of Mrp1 gene was searched, and two putative AREs—ARE1 and ARE2—were found. Using reporter gene and ChIP assay, both ARE1 and ARE2 showed response to and interaction with Nrf2. In 40 cases of cancer tissues, the expression of Nrf2 and MRP1 was measured by immunohistochemistry (IHC). As the quantitive data of IHC indicated, both Nrf2 and MRP1 showed significantly higher expression in tumor tissue than adjacent non-tumor tissue. And more important, the correlation analysis of the two genes proved that their expression was correlative. Taken together, theses data suggested that Nrf2-ARE pathway is required for the regulatory expression of Mrp1 and implicated Nrf2 as a new therapeutic target for MDR.
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Affiliation(s)
- Lili Ji
- Department of Pathology, Shanghai Medical College, Fudan University, Shanghai, China
- Department of Pathology, Medical School of Nantong University, Nantong, Jiangsu Province, China
| | - Hui Li
- Department of Pathology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Pan Gao
- Department of Pathology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Guoguo Shang
- Department of Pathology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Donna D. Zhang
- Department of Pharmacology and Toxicology, University of Arizona, Tucson, Arizona, United States of America
| | - Nong Zhang
- Department of Pathology, Shanghai Medical College, Fudan University, Shanghai, China
- * E-mail: (NZ); (TJ)
| | - Tao Jiang
- Department of Pathology, Shanghai Medical College, Fudan University, Shanghai, China
- Department of Pharmacology and Toxicology, University of Arizona, Tucson, Arizona, United States of America
- * E-mail: (NZ); (TJ)
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22
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Brewer AC, Mustafi SB, Murray TVA, Rajasekaran NS, Benjamin IJ. Reductive stress linked to small HSPs, G6PD, and Nrf2 pathways in heart disease. Antioxid Redox Signal 2013; 18:1114-27. [PMID: 22938199 PMCID: PMC3567781 DOI: 10.1089/ars.2012.4914] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
SIGNIFICANCE Aerobic organisms must exist between the dueling biological metabolic processes for energy and respiration and the obligatory generation of reactive oxygen species (ROS) whose deleterious consequences can reduce survival. Wide fluctuations in harmful ROS generation are circumvented by endogenous countermeasures (i.e., enzymatic and nonenzymatic antioxidants systems) whose capacity decline with aging and are enhanced by disease states. RECENT ADVANCES Substantial efforts on the cellular and molecular underpinnings of oxidative stress has been complemented recently by the discovery that reductive stress similarly predisposes to inheritable cardiomyopathy, firmly establishing that the biological extremes of the redox spectrum play essential roles in disease pathogenesis. CRITICAL ISSUES Because antioxidants by nutritional or pharmacological supplement to prevent or mitigate disease states have been largely disappointing, we hypothesize that lack of efficacy of antioxidants might be related to adverse outcomes in responders at the reductive end of the redox spectrum. As emerging concepts, such as reductive, as opposed, oxidative stress are further explored, there is an urgent and critical gap for biochemical phenotyping to guide the targeted clinical applications of therapeutic interventions. FUTURE DIRECTIONS New approaches are vitally needed for characterizing redox states with the long-term goal to noninvasively assess distinct clinical states (e.g., presymptomatic, end-stage) with the diagnostic accuracy to guide personalized medicine.
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Affiliation(s)
- Alison C Brewer
- Cardiovascular Division, British Heart Foundation Centre of Research Excellence, King's College, London, UK
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23
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Liu RM, Choi J, Forman HJ. Oxidant-induced regulation of glutathione synthesis. ACTA ACUST UNITED AC 2013; Chapter 6:Unit 6.7. [PMID: 23045059 DOI: 10.1002/0471140856.tx0607s08] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This unit describes protocols for characterizing the expression of two glutathione biosynthesis enzymes: gamma-glutamylcysteine synthase (GCS) and gamma-glutamyl transpeptidase (GGT) in response to oxidants. GCS catalyzes the first and rate-limiting step of glutathione synthesis, while GGT degrades extracellular glutathione (GSH) to provide the amino acids required for intracellular synthesis of GSH. Northern blot hybridization is used to quantitatively assess the mRNAs for the two enzymes in response to oxidant. Nuclear run-on is used to determine the rate of transcription.
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Affiliation(s)
- R M Liu
- University Of Alabama At Birmingham, Alabama, USA
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Mohar I, Botta D, White CC, McConnachie LA, Kavanagh TJ. Glutamate cysteine ligase (GCL) transgenic and gene-targeted mice for controlling glutathione synthesis. ACTA ACUST UNITED AC 2013; Chapter 6:Unit6.16. [PMID: 23045016 DOI: 10.1002/0471140856.tx0616s39] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The tripeptide glutathione (GSH) has important antioxidant properties, scavenges free radicals, and serves as a cofactor for glutathione S-transferase conjugation of many xenobiotics. GSH is synthesized in two steps. The first and, often, rate-limiting step is the formation of γ-glutamylcysteine, which is catalyzed by the inducible heterodimeric enzyme glutamate cysteine ligase (GCL). The two subunits of GCL are the catalytic subunit (GCLC) and the modifier subunit (GCLM). In this unit, the generation and basic characterization methodologies of transgenic mouse models that have been developed to (1) conditionally over express both GCL subunits; (2) lack GCLM (Gclm null); and (3) create a hybrid between Gclm conditional over-expressing mice on a Gclm null genetic background are discussed. These models can be used to explore the fundamental role of GCLC and GCLM in GSH synthesis, as well as the toxicological role of GSH and its synthesis in xenobiotic metabolism and response to oxidative stress.
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Affiliation(s)
- Isaac Mohar
- University of Washington, Seattle, Washington, USA
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Competition of nuclear factor-erythroid 2 factors related transcription factor isoforms, Nrf1 and Nrf2, in antioxidant enzyme induction. Redox Biol 2013; 1:183-9. [PMID: 24024152 PMCID: PMC3757680 DOI: 10.1016/j.redox.2013.01.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2012] [Revised: 01/09/2013] [Accepted: 01/10/2013] [Indexed: 12/01/2022] Open
Abstract
Although the Nrf2 (nuclear factor-erythroid 2 p45 subunit-related factor 2) regulated expression of multiple antioxidant and cytoprotective genes through the electrophile responsive element (EpRE) is well established, interaction of Nrf2/EpRE with Nrf1, a closely-related transcription factor, is less well understood. Due to either proteolysis or alternative translation, Nrf1 has been found as proteins of varying size, p120, p95, and p65, which have been described as either activators of EpRE or competitive inhibitors of Nrf2. We investigated the effect of Nrf1 on EpRE-regulated gene expression using the catalytic and modifier subunits of glutamate cysteine ligase (GCLC and GCLM) as models and explored the potential role of Nrf1 in altering their expression in aging and upon chronic exposure to airborne nano-sized particulate matter (nPM). Nrf1 knockout resulted in the increased expression of GCLC and GCLM in human bronchial epithelial (HBE1) cells. Overexpression Nrf2 in combination with either p120 or p65 diminished or failed to further increase the GCLC- and GLCM-EpRE luciferase activity. All known forms of Nrf1 protein, remained unchanged in the lungs of mice with age or in response to nPM. Our study shows that Nrf1 could inhibit EpRE activity in vitro, whereas the precise role of Nrf1 in vivo requires further investigations. We conclude that Nrf1 may not be directly responsible for the loss of Nrf2-dependent inducibility of antioxidant and cytoprotective genes observed in aged animals.
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Key Words
- Air pollution
- ER, endoplasmic reticulum
- Electrophile response element
- EpRE, electrophile response element
- GCL, glutamate cysteine ligase
- GCLC, catalytic subunit of GCL
- GCLM, modifier subunit of GCL
- Glutamate cysteine ligase
- HBE1, human bronchial epithelial cells
- HO-1, heme oxygenase
- Nrf1
- Nrf1, nuclear factor-erythroid 2 p45 subunit-related factor 1
- Nrf2
- Nrf2, nuclear factor-erythroid 2 p45 subunit-related factor 2
- Phase II genes
- nPM, nanoparticulate air pollution
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Dinkova-Kostova AT. The Role of Sulfhydryl Reactivity of Small Molecules for the Activation of the KEAP1/NRF2 Pathway and the Heat Shock Response. SCIENTIFICA 2012; 2012:606104. [PMID: 24278719 PMCID: PMC3820647 DOI: 10.6064/2012/606104] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 11/07/2012] [Indexed: 05/28/2023]
Abstract
The KEAP1/NRF2 pathway and the heat shock response are two essential cytoprotective mechanisms that allow adaptation and survival under conditions of oxidative, electrophilic, and thermal stress by regulating the expression of elaborate networks of genes with versatile protective functions. The two pathways are independently regulated by the transcription factor nuclear factor-erythroid 2 p45-related factor 2 (NRF2) and heat shock factor 1 (HSF1), respectively. The activity of these transcriptional master regulators increases during conditions of stress and also upon encounter of small molecules (inducers), both naturally occurring as well as synthetically produced. Inducers have a common chemical property: the ability to react with sulfhydryl groups. The protein targets of such sulfhydryl-reactive compounds are equipped with highly reactive cysteine residues, which serve as sensors for inducers. The initial cysteine-sensed signal is further relayed to affect the expression of large networks of genes, which in turn can ultimately influence complex cell fate decisions such as life and death. The paper summarizes the multiple lines of experimental evidence demonstrating that the reactivity with sulfhydryl groups is a major determinant of the mechanism of action of small molecule dual activators of the KEAP1/NRF2 pathway and the heat shock response.
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Affiliation(s)
- Albena T. Dinkova-Kostova
- Jacqui Wood Cancer Centre, Division of Cancer Research, Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, James Arrott Drive, Dundee DD1 9SY, UK
- Department of Pharmacology and Molecular Sciences and Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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Lu SC. Glutathione synthesis. Biochim Biophys Acta Gen Subj 2012; 1830:3143-53. [PMID: 22995213 DOI: 10.1016/j.bbagen.2012.09.008] [Citation(s) in RCA: 1501] [Impact Index Per Article: 125.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Revised: 09/05/2012] [Accepted: 09/10/2012] [Indexed: 11/29/2022]
Abstract
BACKGROUND Glutathione (GSH) is present in all mammalian tissues as the most abundant non-protein thiol that defends against oxidative stress. GSH is also a key determinant of redox signaling, vital in detoxification of xenobiotics, and regulates cell proliferation, apoptosis, immune function, and fibrogenesis. Biosynthesis of GSH occurs in the cytosol in a tightly regulated manner. Key determinants of GSH synthesis are the availability of the sulfur amino acid precursor, cysteine, and the activity of the rate-limiting enzyme, glutamate cysteine ligase (GCL), which is composed of a catalytic (GCLC) and a modifier (GCLM) subunit. The second enzyme of GSH synthesis is GSH synthetase (GS). SCOPE OF REVIEW This review summarizes key functions of GSH and focuses on factors that regulate the biosynthesis of GSH, including pathological conditions where GSH synthesis is dysregulated. MAJOR CONCLUSIONS GCL subunits and GS are regulated at multiple levels and often in a coordinated manner. Key transcription factors that regulate the expression of these genes include NF-E2 related factor 2 (Nrf2) via the antioxidant response element (ARE), AP-1, and nuclear factor kappa B (NFκB). There is increasing evidence that dysregulation of GSH synthesis contributes to the pathogenesis of many pathological conditions. These include diabetes mellitus, pulmonary and liver fibrosis, alcoholic liver disease, cholestatic liver injury, endotoxemia and drug-resistant tumor cells. GENERAL SIGNIFICANCE GSH is a key antioxidant that also modulates diverse cellular processes. A better understanding of how its synthesis is regulated and dysregulated in disease states may lead to improvement in the treatment of these disorders. This article is part of a Special Issue entitled Cellular functions of glutathione.
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Affiliation(s)
- Shelly C Lu
- Keck School of Medicine USC, Los Angeles, CA 90033, USA.
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Huang CS, Lii CK, Lin AH, Yeh YW, Yao HT, Li CC, Wang TS, Chen HW. Protection by chrysin, apigenin, and luteolin against oxidative stress is mediated by the Nrf2-dependent up-regulation of heme oxygenase 1 and glutamate cysteine ligase in rat primary hepatocytes. Arch Toxicol 2012; 87:167-78. [DOI: 10.1007/s00204-012-0913-4] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Accepted: 07/24/2012] [Indexed: 12/30/2022]
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Chorley BN, Campbell MR, Wang X, Karaca M, Sambandan D, Bangura F, Xue P, Pi J, Kleeberger SR, Bell DA. Identification of novel NRF2-regulated genes by ChIP-Seq: influence on retinoid X receptor alpha. Nucleic Acids Res 2012; 40:7416-29. [PMID: 22581777 PMCID: PMC3424561 DOI: 10.1093/nar/gks409] [Citation(s) in RCA: 435] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Revised: 04/18/2012] [Accepted: 04/19/2012] [Indexed: 12/14/2022] Open
Abstract
Cellular oxidative and electrophilic stress triggers a protective response in mammals regulated by NRF2 (nuclear factor (erythroid-derived) 2-like; NFE2L2) binding to deoxyribonucleic acid-regulatory sequences near stress-responsive genes. Studies using Nrf2-deficient mice suggest that hundreds of genes may be regulated by NRF2. To identify human NRF2-regulated genes, we conducted chromatin immunoprecipitation (ChIP)-sequencing experiments in lymphoid cells treated with the dietary isothiocyanate, sulforaphane (SFN) and carried out follow-up biological experiments on candidates. We found 242 high confidence, NRF2-bound genomic regions and 96% of these regions contained NRF2-regulatory sequence motifs. The majority of binding sites were near potential novel members of the NRF2 pathway. Validation of selected candidate genes using parallel ChIP techniques and in NRF2-silenced cell lines indicated that the expression of about two-thirds of the candidates are likely to be directly NRF2-dependent including retinoid X receptor alpha (RXRA). NRF2 regulation of RXRA has implications for response to retinoid treatments and adipogenesis. In mouse, 3T3-L1 cells' SFN treatment affected Rxra expression early in adipogenesis, and knockdown of Nrf2-delayed Rxra expression, both leading to impaired adipogenesis.
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Affiliation(s)
- Brian N. Chorley
- Environmental Genomics Section, Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, National Institutes of Health, The Hamner Institutes and Environmental Genetics Section, Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Michelle R. Campbell
- Environmental Genomics Section, Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, National Institutes of Health, The Hamner Institutes and Environmental Genetics Section, Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Xuting Wang
- Environmental Genomics Section, Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, National Institutes of Health, The Hamner Institutes and Environmental Genetics Section, Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Mehmet Karaca
- Environmental Genomics Section, Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, National Institutes of Health, The Hamner Institutes and Environmental Genetics Section, Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Deepa Sambandan
- Environmental Genomics Section, Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, National Institutes of Health, The Hamner Institutes and Environmental Genetics Section, Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Fatu Bangura
- Environmental Genomics Section, Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, National Institutes of Health, The Hamner Institutes and Environmental Genetics Section, Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Peng Xue
- Environmental Genomics Section, Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, National Institutes of Health, The Hamner Institutes and Environmental Genetics Section, Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Jingbo Pi
- Environmental Genomics Section, Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, National Institutes of Health, The Hamner Institutes and Environmental Genetics Section, Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Steven R. Kleeberger
- Environmental Genomics Section, Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, National Institutes of Health, The Hamner Institutes and Environmental Genetics Section, Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Douglas A. Bell
- Environmental Genomics Section, Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, National Institutes of Health, The Hamner Institutes and Environmental Genetics Section, Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
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Fajardo AM, MacKenzie DA, Ji M, Deck LM, Vander Jagt DL, Thompson TA, Bisoffi M. The curcumin analog ca27 down-regulates androgen receptor through an oxidative stress mediated mechanism in human prostate cancer cells. Prostate 2012; 72:612-25. [PMID: 21796654 PMCID: PMC3309160 DOI: 10.1002/pros.21464] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Accepted: 06/29/2011] [Indexed: 12/11/2022]
Abstract
BACKGROUND The androgen receptor (AR) plays a critical role in prostate cancer development and progression. Therefore, the inhibition of AR function is an established therapeutic intervention. Since the expression of the AR is retained and often increased in progressive disease, AR protein down-regulation is a promising therapeutic approach against prostate cancer. We show here that the curcumin analog 27 (ca27) down-regulates AR expression in several prostate cancer cell lines. METHODS ca27 at low micromolar concentrations was tested for its effect on AR expression, AR activation, and induction of oxidative stress in human LNCaP, C4-2, and LAPC-4 prostate cancer cells. RESULTS ca27 induced the down-regulation of AR protein expression in LNCaP, C4-2, and LAPC-4 cells within 12 hr. Further, ca27 led to the rapid induction of reactive oxygen species (ROS). To further support this finding, ca27 treatment led to the activation of the cellular redox sensor NF-E2-related factor 2 (Nrf2) and the induction of the Nrf2-regulated genes NAD(P)H quinone oxidoreductase 1 and aldoketoreductase 1C1. We show that ROS production preceded AR protein loss and that ca27-mediated down-regulation of the AR was attenuated by the antioxidant, N-acetyl cysteine. CONCLUSIONS ca27 induces ROS and mediates AR protein down-regulation through an oxidative stress mechanism of action. Our results suggest that ca27 represents a novel agent for the elucidation of mechanisms of AR down-regulation, which could lead to effective new anti-androgenic strategies for the treatment of advanced prostate cancer.
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Affiliation(s)
- Alexandra M. Fajardo
- Departmentof Biochemistry and Molecular Biology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
- Departmentof Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Debra A. MacKenzie
- Departmentof Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Ming Ji
- Departmentof Biochemistry and Molecular Biology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Lorraine M. Deck
- Departmentof Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico
| | - David L. Vander Jagt
- Departmentof Biochemistry and Molecular Biology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Todd A. Thompson
- Departmentof Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
- Universityof New Mexico Cancer Center, Albuquerque, New Mexico
| | - Marco Bisoffi
- Departmentof Biochemistry and Molecular Biology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
- Universityof New Mexico Cancer Center, Albuquerque, New Mexico
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31
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Zhu W, Jia Q, Wang Y, Zhang Y, Xia M. The anthocyanin cyanidin-3-O-β-glucoside, a flavonoid, increases hepatic glutathione synthesis and protects hepatocytes against reactive oxygen species during hyperglycemia: Involvement of a cAMP-PKA-dependent signaling pathway. Free Radic Biol Med 2012; 52:314-27. [PMID: 22085656 DOI: 10.1016/j.freeradbiomed.2011.10.483] [Citation(s) in RCA: 163] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Revised: 10/14/2011] [Accepted: 10/24/2011] [Indexed: 12/21/2022]
Abstract
Enhanced oxidative stress due to high glucose contributes to pathological changes in diabetes-related liver complications. Reducing oxidative stress may alleviate these pathogenic processes. Anthocyanin, a natural antioxidant, has been reported to reduce intracellular reactive oxygen species (ROS) levels but the mechanism of this reduction is not fully understood. The glutathione (GSH) antioxidant system is critical for counteracting oxidative stress-induced intracellular injury. In this study, we evaluated the mechanism of the anthocyanin-mediated regulation of GSH synthesis and reduction in intracellular ROS levels. We observed that treatment of human HepG2 cells with the anthocyanin C3G significantly reduced ROS levels induced by high glucose. C3G incubation increased glutamate-cysteine ligase expression, which in turn mediated the reduction in ROS levels. However, the upregulation of glutamate-cysteine ligase catalytic subunit (Gclc) expression by C3G occurred independent of the Nrf1/2 transcription factors. Notably, the cAMP-response element binding protein (CREB) was identified as the target transcription factor involved in the C3G-mediated upregulation of Gclc expression. C3G increased phosphorylation of CREB through protein kinase A (PKA) activation, which induced a CREB-mediated upregulation of Gclc transcription. In vivo, treatment with C3G increased the GSH synthesis in the liver of diabetic db/db mice through PKA-CREB-dependent induction of Gclc expression. Finally, oxidative stress determined by lipid peroxidation, neutrophil infiltration, and hepatic steatosis was attenuated in C3G-treated db/db mice. Our results demonstrate that the anthocyanin C3G has an effect of activating GSH synthesis through a novel antioxidant defense mechanism against excessive ROS production, contributing to the prevention of hyperglycemia-induced hepatic oxidative damage.
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Affiliation(s)
- Wei Zhu
- Department of Toxicology, Guangzhou Center for Disease Control and Prevention, Guangzhou, Guangdong, People's Republic of China
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Kim AD, Zhang R, Kang KA, You HJ, Hyun JW. Increased glutathione synthesis following Nrf2 activation by vanadyl sulfate in human chang liver cells. Int J Mol Sci 2011; 12:8878-94. [PMID: 22272109 PMCID: PMC3257106 DOI: 10.3390/ijms12128878] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 11/03/2011] [Accepted: 11/21/2011] [Indexed: 01/28/2023] Open
Abstract
Jeju ground water, containing vanadium compounds, was shown to increase glutathione (GSH) levels as determined by a colorimetric assay and confocal microscopy. To investigate whether the effects of Jeju ground water on GSH were specifically mediated by vanadium compounds, human Chang liver cells were incubated for 10 passages in media containing deionized distilled water (DDW), Jeju ground water (S1 and S3), and vanadyl sulfate (VOSO(4)). Vanadyl sulfate scavenged superoxide anion, hydroxyl radical and intracellular reactive oxygen species. Vanadyl sulfate effectively increased cellular GSH level and up-regulated mRNA and protein expression of a catalytic subunit of glutamate cysteine ligase (GCLC), which is involved in GSH synthesis. The induction of GCLC expression by vanadyl sulfate was found to be mediated by transcription factor erythroid transcription factor NF-E2 (Nrf2), which critically regulates GCLC by binding to the antioxidant response elements (AREs). Vanadyl sulfate treatment increased the nuclear translocation of Nrf2 and the accumulation of phosphorylated Nrf2. Extracellular regulated kinase (ERK) contributed to ARE-driven GCLC expression via Nrf2 activation. Vanadyl sulfate induced the expression of the active phospho form of ERK. Taken together, these results suggest that the increase in GSH level by Jeju ground water is, at least in part, due to the effects of vanadyl sulfate via the Nrf2-mediated induction of GCLC.
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Affiliation(s)
- Areum Daseul Kim
- School of Medicine, Jeju National University, Jeju 690-756, Korea; E-Mails: (A.D.K.); (R.Z.)
| | - Rui Zhang
- School of Medicine, Jeju National University, Jeju 690-756, Korea; E-Mails: (A.D.K.); (R.Z.)
| | - Kyoung Ah Kang
- Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706, Korea; E-Mail:
| | - Ho Jin You
- Department of Biomaterials, DNA Repair Center, Chosun University, Gwangju 501-759, Korea; E-Mail:
| | - Jin Won Hyun
- School of Medicine, Jeju National University, Jeju 690-756, Korea; E-Mails: (A.D.K.); (R.Z.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +82-064-754-3838; Fax: +82-064-702-2687
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Modulation of oxidative stress and mitochondrial function by the ketogenic diet. Epilepsy Res 2011; 100:295-303. [PMID: 22078747 DOI: 10.1016/j.eplepsyres.2011.09.021] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 08/17/2011] [Accepted: 09/07/2011] [Indexed: 12/23/2022]
Abstract
The ketogenic diet (KD) is a high-fat, low carbohydrate diet that is used as a therapy for intractable epilepsy. However, the mechanism(s) by which the KD achieves neuroprotection and/or seizure control are not yet known. The broad efficacy of the KD in diverse epilepsies coupled with its profound influence on metabolism suggests that mitochondrial functions may be critical in its mechanism(s) of seizure control. Mitochondria subserve important cellular functions that include the production of cellular ATP, control of apoptosis, maintenance of calcium homeostasis and the production and elimination of reactive oxygen species (ROS). This review will focus on recent literature reporting the regulation of mitochondrial functions and redox signaling by the KD. The review highlights a potential mechanism of the KD involving the production of low levels of redox signaling molecules such as H(2)O(2) and electrophiles e.g. 4-hydroxynonenal (4-HNE), which in turn activate adaptive pathways such as the protective transcription factor, NF E2-related factor 2 (Nrf2). This can ultimately result in increased production of antioxidants (e.g. GSH) and detoxification enzymes which may be critical in mediating the protective effects of the KD.
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Brigelius-Flohé R, Flohé L. Basic principles and emerging concepts in the redox control of transcription factors. Antioxid Redox Signal 2011; 15:2335-81. [PMID: 21194351 PMCID: PMC3166203 DOI: 10.1089/ars.2010.3534] [Citation(s) in RCA: 416] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Convincing concepts of redox control of gene transcription have been worked out for prokaryotes and lower eukaryotes, whereas the knowledge on complex mammalian systems still resembles a patchwork of poorly connected findings. The article, therefore, reviews principles of redox regulation with special emphasis on chemical feasibility, kinetic requirements, specificity, and physiological context, taking well investigated mammalian transcription factor systems, nuclear transcription factor of bone marrow-derived lymphocytes (NF-κB), and kelch-like ECH-associated protein-1 (Keap1)/Nrf2, as paradigms. Major conclusions are that (i) direct signaling by free radicals is restricted to O(2)•- and •NO and can be excluded for fast reacting radicals such as •OH, •OR, or Cl•; (ii) oxidant signals are H(2)O(2), enzymatically generated lipid hydroperoxides, and peroxynitrite; (iii) free radical damage is sensed via generation of Michael acceptors; (iv) protein thiol oxidation/alkylation is the prominent mechanism to modulate function; (v) redox sensors must be thiol peroxidases by themselves or proteins with similarly reactive cysteine or selenocysteine (Sec) residues to kinetically compete with glutathione peroxidase (GPx)- and peroxiredoxin (Prx)-type peroxidases or glutathione-S-transferases, respectively, a postulate that still has to be verified for putative mammalian sensors. S-transferases and Prxs are considered for system complementation. The impact of NF-κB and Nrf2 on hormesis, management of inflammatory diseases, and cancer prevention is critically discussed.
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Affiliation(s)
- Regina Brigelius-Flohé
- Department Biochemistry of Micronutrients, German Institute of Human Nutrition Potsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, Nuthetal, Germany.
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Brewer AC, Murray TVA, Arno M, Zhang M, Anilkumar NP, Mann GE, Shah AM. Nox4 regulates Nrf2 and glutathione redox in cardiomyocytes in vivo. Free Radic Biol Med 2011; 51:205-15. [PMID: 21554947 PMCID: PMC3112490 DOI: 10.1016/j.freeradbiomed.2011.04.022] [Citation(s) in RCA: 136] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Revised: 03/21/2011] [Accepted: 04/11/2011] [Indexed: 12/16/2022]
Abstract
NADPH oxidase-4 (Nox4) is an important modulator of redox signaling that is inducible at the level of transcriptional expression in multiple cell types. By contrast to other Nox enzymes, Nox4 is continuously active without requiring stimulation. We reported recently that expression of Nox4 is induced in the adult heart as an adaptive stress response to pathophysiological insult. To elucidate the potential downstream target(s) regulated by Nox4, we performed a microarray screen to assess the transcriptomes of transgenic (tg) mouse hearts in which Nox4 was overexpressed. The screen revealed a significant increase in the expression of many antioxidant and detoxifying genes regulated by Nrf2 in tg compared to wild-type (wt) mouse hearts, and this finding was subsequently confirmed by Q-PCR. Expression of glutathione biosynthetic and recycling enzymes was increased in tg hearts and associated with higher levels of both GSH and the ratio of reduced:oxidised GSH, compared to wt hearts. The increases in expression of the antioxidant genes and the changes in glutathione redox effected by Nox4 were ablated in an Nrf2-null genetic background. These data therefore demonstrate that Nox4 can activate the Nrf2-regulated pathway, and suggest a potential role for Nox4 in the regulation of GSH redox in cardiomyocytes.
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Key Words
- nadph, nicotinamide adenine dinucleotide phosphate
- nrf2, nf-e2-related factor 2
- q-pcr, quantitative polymerase chain reaction
- er, endoplasmic reticulum
- eb, embryoid body
- αmhc, α myosin heavy chain
- βmhc, β myosin heavy chain
- mlc2v, myosin regulatory light chain 2
- rt, reverse transcriptase
- dtt, dithiothreitol
- page, polyacrylamide gel electrophoresis
- ecl, enhanced chemiluminescence
- pbs, phosphate-buffered saline
- pvdf, polyvinylidene difluoride
- sem, standard error of the mean
- elisa, enzyme-linked immunosorbent serologic assay
- nox4
- nrf2
- cardiomyocytes
- glutathione
- reactive oxygen species
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Affiliation(s)
- Alison C Brewer
- King's College London British Heart Foundation Centre of Research Excellence, Cardiovascular Division, London, UK.
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Singh S, Vrishni S, Singh BK, Rahman I, Kakkar P. Nrf2-ARE stress response mechanism: a control point in oxidative stress-mediated dysfunctions and chronic inflammatory diseases. Free Radic Res 2011; 44:1267-88. [PMID: 20815789 DOI: 10.3109/10715762.2010.507670] [Citation(s) in RCA: 216] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Nrf2, a redox sensitive transcription factor, plays a pivotal role in redox homeostasis during oxidative stress. Nrf2 is sequestered in cytosol by an inhibitory protein Keap1 which causes its proteasomal degradation. In response to electrophilic and oxidative stress, Nrf2 is activated, translocates to nucleus, binds to antioxidant response element (ARE), thus upregulates a battery of antioxidant and detoxifying genes. This function of Nrf2 can be significant in the treatment of diseases, such as cancer, neurodegenerative, cardiovascular and pulmonary complications, where oxidative stress causes Nrf2 derangement. Nrf2 upregulating potential of phytochemicals has been explored, in facilitating cure for various ailments while, in cancer cells, Nrf2 upregulation causes chemoresistance. Therefore, Nrf2 emerges as a key regulator in oxidative stress-mediated diseases and Nrf2 silencing can open avenues in cancer treatment. This review summarizes Nrf2-ARE stress response mechanism and its role as a control point in oxidative stress-induced cellular dysfunctions including chronic inflammatory diseases.
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Affiliation(s)
- Shruti Singh
- Herbal Research Section, Indian Institute of Toxicology Research, CSIR, PO Box-80, Mahatma Gandhi Marg, Lucknow 226001, Uttar Pradesh, India
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D’Aguanno S, D’Alessandro A, Pieroni L, Roveri A, Zaccarin M, Marzano V, Canio MD, Bernardini S, Federici G, Urbani A. New Insights into Neuroblastoma Cisplatin Resistance: A Comparative Proteomic and Meta-Mining Investigation. J Proteome Res 2010; 10:416-28. [DOI: 10.1021/pr100457n] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Simona D’Aguanno
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Annamaria D’Alessandro
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Luisa Pieroni
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Antonella Roveri
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Mattia Zaccarin
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Valeria Marzano
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Michele De Canio
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Sergio Bernardini
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Giorgio Federici
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Andrea Urbani
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
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Senggunprai L, Kukongviriyapan V, Prawan A, Kukongviriyapan U. Consumption of Syzygium gratum promotes the antioxidant defense system in mice. PLANT FOODS FOR HUMAN NUTRITION (DORDRECHT, NETHERLANDS) 2010; 65:403-409. [PMID: 21104319 DOI: 10.1007/s11130-010-0200-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Several vegetables have been shown to possess cytoprotective and antioxidant effects with various mechanisms of action. The aim of this study was to determine the antioxidant effects and mechanism underlying of Syzygium gratum, a dietary and herbal plant commonly found in the Southeast Asia. Additionally, its effects on the induction of endogenous antioxidant defensive system were also investigated. Results showed that the leaf extract possessed an exceptionally strong antioxidant and intracellular oxygen radical scavenging activity in both aqueous and ethanolic extracts. The plant aqueous extract was further studied in C57BL/6J mice to evaluate its effects in vivo. The extract was well tolerated by the animals throughout the 30 days of study. The cytoprotective enzyme, heme oxygenase (HO-1) activity was significantly increased in the high dose-treated animals (1 g/kg/day). Consistent with the enzymatic activity, the expression of HO-1 mRNA tended to increase in those mice. There was no significant increase in hepatic γ-glutamylcysteine ligase (γ-GCL) activity, glutathione levels and GCL mRNA expression. Taken together, this study provides evidence that S. gratum exhibits potent direct antioxidant properties and can induce cytoprotective enzyme in vivo. Consumption of S. gratum may provide a health benefit against oxidative stress and other related disorders.
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Affiliation(s)
- Laddawan Senggunprai
- Department of Pharmacology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
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39
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Hayes JD, McMahon M, Chowdhry S, Dinkova-Kostova AT. Cancer chemoprevention mechanisms mediated through the Keap1-Nrf2 pathway. Antioxid Redox Signal 2010; 13:1713-48. [PMID: 20446772 DOI: 10.1089/ars.2010.3221] [Citation(s) in RCA: 412] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The cap'n'collar (CNC) bZIP transcription factor Nrf2 controls expression of genes for antioxidant enzymes, metal-binding proteins, drug-metabolising enzymes, drug transporters, and molecular chaperones. Many chemicals that protect against carcinogenesis induce Nrf2-target genes. These compounds are all thiol-reactive and stimulate an adaptive response to redox stress in cells. Such agents induce the expression of genes that posses an antioxidant response element (ARE) in their regulatory regions. Under normal homeostatic conditions, Nrf2 activity is restricted through a Keap1-dependent ubiquitylation by Cul3-Rbx1, which targets the CNC-bZIP transcription factor for proteasomal degradation. However, as the substrate adaptor function of Keap1 is redox-sensitive, Nrf2 protein evades ubiquitylation by Cul3-Rbx1 when cells are treated with chemopreventive agents. As a consequence, Nrf2 accumulates in the nucleus where it heterodimerizes with small Maf proteins and transactivates genes regulated through an ARE. In this review, we describe synthetic compounds and phytochemicals from edible plants that induce Nrf2-target genes. We also discuss evidence for the existence of different classes of ARE (a 16-bp 5'-TMAnnRTGABnnnGCR-3' versus an 11-bp 5'-RTGABnnnGCR-3', with or without the embedded activator protein 1-binding site 5'-TGASTCA-3'), species differences in the ARE-gene battery, and the identity of critical Cys residues in Keap1 required for de-repression of Nrf2 by chemopreventive agents.
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Affiliation(s)
- John D Hayes
- Biomedical Research Institute, Ninewells Hospital, University of Dundee, Scotland, United Kingdom.
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Katakami N, Kaneto H, Matsuoka TA, Takahara M, Imamura K, Ishibashi F, Kanda T, Kawai K, Osonoi T, Kashiwagi A, Kawamori R, Matsuhisa M, Shimomura I, Yamasaki Y. Accumulation of gene polymorphisms related to oxidative stress is associated with myocardial infarction in Japanese type 2 diabetic patients. Atherosclerosis 2010; 212:534-8. [DOI: 10.1016/j.atherosclerosis.2010.06.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 05/25/2010] [Accepted: 06/08/2010] [Indexed: 10/19/2022]
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Kim H, Jung Y, Shin BS, Kim H, Song H, Bae SH, Rhee SG, Jeong W. Redox regulation of lipopolysaccharide-mediated sulfiredoxin induction, which depends on both AP-1 and Nrf2. J Biol Chem 2010; 285:34419-28. [PMID: 20826812 DOI: 10.1074/jbc.m110.126839] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Sulfiredoxin (Srx) is an enzyme that catalyzes the reduction of cysteine sulfinic acid of hyperoxidized peroxiredoxins and exerts a protective antioxidant role. Here we investigated the regulatory mechanism of Srx induction by lipopolysaccharide (LPS) in mouse macrophages. LPS up-regulated Srx expression on the transcriptional level. The promoter region of the Srx gene contained putative NF-κB and AP-1 (activator protein-1) sites, and the proximal site of three AP-1 sites was embedded within the antioxidant response element (ARE), a cis-acting element for Nrf2 (nuclear factor erythroid 2-related factor). Mutational analysis of the Srx promoter revealed that Srx induction is dependent on AP-1 sites and ARE but not on NF-κB sites. Consistently, both transcription factors, AP-1 and Nrf2, were required for LPS-mediated Srx induction, as revealed by chromatin immunoprecipitation using antibodies specific for c-Jun and c-Fos and little Srx induction in Nrf2-null bone marrow-derived macrophages. Among mitogen-activated protein kinases that mediate the signal transduction by LPS, JNK played a major role in Srx induction. Moreover, chemical antioxidants, such as N-acetylcysteine and butylated hydroxyanisole, and the NADPH oxidase inhibitor diphenyleneiodonium inhibited Srx induction as well as generation of reactive oxygen species, both of which were also suppressed in Nox2 (NADPH oxidase 2)-deficient bone marrow-derived macrophages. These results suggest that LPS-mediated Srx induction is dependent on both AP-1 and Nrf2, which is regulated by Nox2-derived reactive oxygen species.
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Affiliation(s)
- Hojin Kim
- Department of Life Science, Division of Life and Pharmaceutical Sciences, Center for Cell Signaling and Drug Discovery Research, Ewha Womans University, Seoul 120-750, Korea
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Hou DX, Kumamoto T. Flavonoids as protein kinase inhibitors for cancer chemoprevention: direct binding and molecular modeling. Antioxid Redox Signal 2010; 13:691-719. [PMID: 20070239 DOI: 10.1089/ars.2009.2816] [Citation(s) in RCA: 133] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Protein kinases play crucial roles in the regulation of multiple cell signaling pathways and cellular functions. Deregulation of protein kinase function has been implicated in carcinogenesis. The inhibition of protein kinases has emerged as an important target for cancer chemoprevention and therapy. Accumulated data revealed that flavonoids exert chemopreventive effects through acting at protein kinase signaling pathways, more than as conventional hydrogen-donating antioxidants. Recent studies show that flavonoids can bind directly to some protein kinases, including Akt/protein kinase B (Akt/PKB), Fyn, Janus kinase 1 (JAK1), mitogen-activated protein kinase kinase 1 (MEK1), phosphoinositide 3-kinase (PI3K), mitogen-activated protein (MAP) kinase kinase 4 (MKK4), Raf1, and zeta chain-associated 70-kDa protein (ZAP-70) kinase, and then alter their phosphorylation state to regulate multiple cell signaling pathways in carcinogenesis processes. In this review, we report recent results on the interactions of flavonoids and protein kinases, especially their direct binding and molecular modeling. The data suggest that flavonoids act as protein kinase inhibitors for cancer chemoprevention that were thought previously as conventional hydrogen-donating antioxidant. Moreover, the molecular modeling data show some hints for creating natural compound-based protein kinase inhibitors for cancer chemoprevention and therapy.
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Affiliation(s)
- De-Xing Hou
- The United Graduate School of Agricultural Sciences, Faculty of Agriculture, Kagoshima University, Kagoshima City, Japan
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Zhang H, Forman HJ. Reexamination of the electrophile response element sequences and context reveals a lack of consensus in gene function. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2010; 1799:496-501. [PMID: 20478426 DOI: 10.1016/j.bbagrm.2010.05.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Revised: 04/12/2010] [Accepted: 05/07/2010] [Indexed: 12/18/2022]
Abstract
The electrophile response element (EpRE) is essential for regulation of many genes involved in protection against toxic agents. Putative EpRE core sequences (TGAnnnnGC) are localized in 5'-flanking regions (5'-UTR) of these genes but specificity of the internal bases and whether location affects function has not been refined. The catalytic subunit of human glutamate cysteine ligase (GCLC) gene is well documented to be under EpRE regulation and four sequences having an EpRE "consensus" sequence were reported with only one (EpRE 4) responsive to electrophiles. Using GCLC as a model, we asked whether the internal variable or flanking nucleotides and the location of the sequence were required for functional activity in response to 4-hydroxenonenal (HNE). We found that thirteen putative EpRE core sequences (TGAnnnnGC) were localized in 5'-UTR of GCLC and confirmed that EpRE 4 showed both constitutive and HNE-inducible activity. Four other sequences exhibited only constitutive activity while other putative EpREs demonstrated no activity. Nucleotide mutagenesis demonstrated specific requirements for internal and flanking nucleotides that were specific for the electrophilic response and that a TRE-like sequence within EpRE was essential for basal (non-electrophile-dependent) activity. Furthermore, EpRE 4 relocated to positions of other putative EpREs maintained activity but moving other EpREs to the EpRE 4 location did not. Thus in GCLC, specific flanking and internal nucleotides within EpRE were far more important for function than previously described while location did not influence activity. These two findings bring into question the meaning of the phrase, "consensus sequence" for this important cis element.
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Affiliation(s)
- Hongqiao Zhang
- School of Natural Sciences, University of California at Merced, Merced, CA 95343, USA
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Klaassen CD, Reisman SA. Nrf2 the rescue: effects of the antioxidative/electrophilic response on the liver. Toxicol Appl Pharmacol 2010; 244:57-65. [PMID: 20122946 DOI: 10.1016/j.taap.2010.01.013] [Citation(s) in RCA: 303] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Revised: 12/23/2009] [Accepted: 01/26/2010] [Indexed: 02/06/2023]
Abstract
Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that positively regulates the basal and inducible expression of a large battery of cytoprotective genes. These gene products include proteins that catalyze reduction reactions (NAD(P)H:quinone oxidoreductase 1, Nqo1), conjugation reactions (glutathione-S-transferases, Gsts and UDP-glucuronosyltransferases, Ugts), as well as the efflux of potentially toxic xenobiotics and xenobiotic conjugates (multidrug resistance-associated proteins, Mrps). The significance of Nrf2 in the liver has been established, as livers of Nrf2-null mice are more susceptible to various oxidative/electrophilic stress-induced pathologies than wild-type mice. In contrast, both pharmacological and genetic models of hepatic Nrf2 activation are protective against oxidative/electrophilic stress. Furthermore, because certain Nrf2-target genes in the liver could affect the distribution, metabolism, and excretion of xenobiotics, the effects of Nrf2 on the kinetics of drugs and other xenobiotics should also be considered, with a special emphasis on metabolism and excretion. Therefore, this review highlights the research that has contributed to the understanding of the importance of Nrf2 in toxicodynamics and toxicokinetics, especially that which pertains to the liver.
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Affiliation(s)
- Curtis D Klaassen
- Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, KS 66160-7417, USA.
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Müller M, Banning A, Brigelius-Flohé R, Kipp A. Nrf2 target genes are induced under marginal selenium-deficiency. GENES AND NUTRITION 2010; 5:297-307. [PMID: 21189866 DOI: 10.1007/s12263-010-0168-8] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Accepted: 01/10/2010] [Indexed: 12/13/2022]
Abstract
A suboptimal selenium supply appears to prevail in Europe. The current study, therefore, was focused on the changes in gene expression under a suboptimal selenium intake. Previous microarray analyses in the colon of mice fed either a selenium-adequate or a moderately deficient diet revealed a change in genes of several pathways. Severe selenium-deficiency has been found previously to influence Nrf2-regulated genes of the adaptive response. Since the previous pathway analyses were done with a program not searching for Nrf2 target genes, respective genes were manually selected and confirmed by qPCR. qPCR revealed an induction of phase II (Nqo1, Gsts, Sult1b1 and Ugt1a6) and antioxidant enzymes (Hmox1, Mt2, Prdx1, Srxn1, Sod1 and Gclc) under the selenium-poor diet, which is considered to compensate for the loss of selenoproteins. The strongest effects were observed in the duodenum where preferentially genes for antioxidant enzymes were up-regulated. These also include the mRNA of the selenoproteins TrxR1 and GPx2 that would enable their immediate translation upon selenium refeeding. The down-regulation of Gsk3β in moderate selenium-deficiency observed in the previous paper provides a possible explanation for the activation of the Nrf2 pathway, because inhibition of GSK3β results in the nuclear accumulation of Nrf2.
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Mutation screening of the glutamate cysteine ligase modifier (GCLM) gene in patients with schizophrenia. Psychiatr Genet 2009; 19:201-8. [PMID: 19455074 DOI: 10.1097/ypg.0b013e32832cef21] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND Experimental evidences show that glutathione and its rate-limiting synthesizing enzyme, the glutamate-cysteine ligase (GCL), are involved in the pathogenesis of schizophrenia. Furthermore, genetic association has been previously reported between two single nucleotide polymorphisms lying in noncoding regions of glutamate cysteine ligase modifier (GCLM) gene, which specifies for the modifier subunit of GCL and schizophrenia. OBJECTIVE We wanted to investigate the presence of GCLM true functional mutations, likely in linkage disequilibrium with the previously identified single nucleotide polymorphism alleles, in the same set of cases that allowed the detection of the original association signal. METHODS We screened all the coding regions of GCLM and their intronic flanking vicinities in 353 patients with schizophrenia by direct DNA sequencing. RESULTS Ten sequence variations were identified, five of which were not previously described. None of these DNA changes was within the GCLM coding sequence and in-silico analysis failed to indicate functional impairment induced by these variations. Furthermore, screening of normal controls and downstream statistical analyses revealed no significant relationship of any of these DNA variants with schizophrenia. CONCLUSION It is unlikely that functional mutations in the GCLM gene could play a major role in genetic predisposition to schizophrenia and further studies will be required to assess its etiological function in the disease.
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47
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Targeting NRF2 signaling for cancer chemoprevention. Toxicol Appl Pharmacol 2009; 244:66-76. [PMID: 19732782 DOI: 10.1016/j.taap.2009.08.028] [Citation(s) in RCA: 229] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Revised: 08/13/2009] [Accepted: 08/26/2009] [Indexed: 02/06/2023]
Abstract
Modulation of the metabolism and disposition of carcinogens through induction of cytoprotective enzymes is one of several promising strategies to prevent cancer. Chemopreventive efficacies of inducers such as dithiolethiones and sulforaphane have been extensively studied in animals as well as in humans. The KEAP1-NRF2 system is a key, but not unilateral, molecular target for these chemopreventive agents. The transcription factor NRF2 (NF-E2-related factor 2) is a master regulator of the expression of a subset of genes, which produce proteins responsible for the detoxication of electrophiles and reactive oxygen species as well as the removal or repair of some of their damage products. It is believed that chemopreventive enzyme inducers affect the interaction between KEAP1 and NRF2 through either mediating conformational changes of the KEAP1 protein or activating phosphorylation cascades targeting the KEAP1-NRF2 complex. These events in turn affect NRF2 stability and trafficking. Recent advances elucidating the underlying structural biology of KEAP1-NRF2 signaling and identification of the gene clusters under the transcriptional control of NRF2 are facilitating understanding of the potential pleiotropic effects of NRF2 activators and discovery of novel classes of potent chemopreventive agents such as the triterpenoids. Although there is appropriately a concern regarding a deleterious role of the KEAP1-NRF2 system in cancer cell biology, especially as the pathway affects cell survival and drug resistance, the development and the use of NRF2 activators as chemopreventive agents still holds a great promise for protection of normal cells from a diversity of environmental stresses that contribute to the burden of cancer and other chronic, degenerative diseases.
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Askwith T, Zeng W, Eggo MC, Stevens MJ. Oxidative stress and dysregulation of the taurine transporter in high-glucose-exposed human Schwann cells: implications for pathogenesis of diabetic neuropathy. Am J Physiol Endocrinol Metab 2009; 297:E620-8. [PMID: 19602579 PMCID: PMC3833996 DOI: 10.1152/ajpendo.00287.2009] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2009] [Accepted: 06/30/2009] [Indexed: 02/07/2023]
Abstract
In human Schwann cells, the role of taurine in regulating glucose-induced changes in antioxidant defense systems has been examined. Treatment with high glucose for 7 days induced reactive oxygen species, increased 4-hydroxynoneal adducts (20 +/- 5%, P < 0.05) and poly(ADP-ribosyl)ated proteins (40 +/- 13%, P < 0.05). Increases in these markers of oxidative stress were reversed by simultaneous incubation in 0.25 mM taurine. Both high glucose and taurine independently increased superoxide dismutase and catalase activity and decreased glutathione levels, but their effects were not additive. Glucose reduced taurine transporter (TauT) mRNA and protein in a dose-dependent manner with maximal decreases of 66 +/- 6 and 63 +/- 12%, respectively (P < 0.05 both). The V(max) for taurine uptake was decreased in 30 mM glucose from 61 +/- 5 to 42 +/- 3 pmol x min(-1) x mg protein(-1) (P < 0.001). Glucose-induced TauT downregulation could be reversed by inhibition of aldose reductase, a pathway that depletes NADPH and increases osmotic stress and protein glycation. TauT protein was increased more than threefold, and the V(max) for taurine uptake doubled (P < 0.05 both) by prooxidants. TauT downregulation was reversed both by treatment with the antioxidant alpha-lipoic acid, which increased TauT mRNA by 60% and V(max) by 50% (P < 0.05 both), and by the aldose reductase inhibitor sorbinil, which increased TauT mRNA 380% and V(max) by 98% (P < 0.01 both). These data highlight the potential therapeutic benefits of taurine supplementation in diabetic complications and provide mechanisms whereby taurine restoration could be achieved in order to prevent or reverse diabetic complications.
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Affiliation(s)
- Trevor Askwith
- Dept. of Clinical and Experimental Medicine, Univ. of Birmingham, Birmingham, B15 2TT UK
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MacLeod AK, McMahon M, Plummer SM, Higgins LG, Penning TM, Igarashi K, Hayes JD. Characterization of the cancer chemopreventive NRF2-dependent gene battery in human keratinocytes: demonstration that the KEAP1-NRF2 pathway, and not the BACH1-NRF2 pathway, controls cytoprotection against electrophiles as well as redox-cycling compounds. Carcinogenesis 2009; 30:1571-80. [PMID: 19608619 DOI: 10.1093/carcin/bgp176] [Citation(s) in RCA: 245] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
To better understand the role of transcription factor NF-E2-related factor (NRF) 2 in the human and its contribution to cancer chemoprevention, we have knocked down its negative regulators, Kelch-like ECH-associated protein 1 (KEAP1) and broad-complex, tramtrack and bric à brac and cap'n'collar homology 1 (BACH1), in HaCaT keratinocytes. Whole-genome microarray revealed that knockdown of KEAP1 resulted in 23 messenger RNAs (mRNAs) being up-regulated > or = 2.0-fold. mRNA for aldo-keto reductase (AKR) 1B10, AKR1C1, AKR1C2 and AKR1C3 were induced to the greatest extent, showing increases of between 12- and 16-fold, whereas mRNA for glutamate-cysteine ligase catalytic and modifier subunits, NAD(P)H:quinone oxidoreductase-1 and haem oxygenase-1 (HMOX1) were induced between 2.0- and 4.8-fold. Knockdown of BACH1 increased HMOX1 135-fold but induced the other genes examined to a maximum of only 2.7-fold. Activation of NRF2, by KEAP1 knockdown, caused a 75% increase in the amount of glutathione in HaCaT cells and a 1.4- to 1.6-fold increase in their resistance to the electrophiles acrolein, chlorambucil and cumene hydroperoxide (CuOOH), as well as the redox-cycling agent menadione. Inhibition of glutathione synthesis during KEAP1 knockdown, by treatment with buthionine sulfoximine, abrogated resistance to acrolein, chlorambucil and CuOOH, but not to menadione. In contrast, knockdown of BACH1 did not increase glutathione levels or resistance to xenobiotics. Knockdown of NRF2 in HaCaT cells decreased glutathione to approximately 80% of normal homeostatic levels and similarly reduced their tolerance of electrophiles. Thus, the KEAP1-NRF2 pathway determines resistance to electrophiles and redox-cycling compounds in human keratinocytes through glutathione-dependent and glutathione-independent mechanisms. This study also shows that AKR1B10, AKR1C1 and AKR1C2 proteins have potential utility as biomarkers for NRF2 activation in the human.
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Affiliation(s)
- A Kenneth MacLeod
- Biomedical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland, UK
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Brigelius-Flohé R, Banning A. Part of the Series: From dietary antioxidants to regulators in cellular signaling and gene regulation. Free Radic Res 2009; 40:775-87. [PMID: 17015256 DOI: 10.1080/10715760600722643] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The association of decreased cancer risk with intake of cruciferous vegetables and selenium is stronger than that reported for fruits and vegetables in general. An active constituent in cruciferae is sulforaphane. Chemopreventive effects of both, sulforaphane and selenium have been attributed to an antioxidant action which certainly is too simplicistic. Sulforaphane induces via activation of the Nrf2/Keap1 system phase 2 enzymes that protect against carcinogens and oxidants. Induced enzymes comprise the selenoproteins thioredoxin reductase-1 (TrxR1) and gastrointestinal glutathione peroxidase (GI-GPx, GPx2), which contain antioxidant response elements (ARE) in their promoter regions. Translational realisation of the enhanced transcripts depends on adequate selenium supply, which explains the synergism of Nrf2 activators and selenium. Regarding tumorigenesis the role of TrxR1 is ambiguous: it is essential for fast tumor cell growth but also diminishes vascularisation of tumors. The anticarcinogenic role of GI-GPx is evident from enhanced gastrointestinal tumor formation in gpx2/gpx1 double KO mice.
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Affiliation(s)
- Regina Brigelius-Flohé
- German Institute of Human Nutrition, Potsdam-Rehbruecke, Arthur-Scheunert-Allee 114 - 116, D-14558, Nuthetal, Germany.
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