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Htut NW, Onkoksoong T, Saelim M, Kueanjinda P, Sampattavanich S, Panich U. Live-cell imaging Unveils stimulus-specific dynamics of Nrf2 activation in UV-exposed melanoma cells: Implications for antioxidant compound screening. Free Radic Biol Med 2024; 211:1-11. [PMID: 38092271 DOI: 10.1016/j.freeradbiomed.2023.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 12/06/2023] [Accepted: 12/08/2023] [Indexed: 01/06/2024]
Abstract
The transcription factor Nuclear factor e2-related factor 2 (Nrf2) is pivotal in orchestrating cellular antioxidant defense mechanisms, particularly in skin cells exposed to ultraviolet (UV) radiation and electrophilic phytochemicals. To comprehensively investigate Nrf2's role in maintaining cellular redox equilibrium following UV-induced stress, we engineered a novel Nrf2 fusion-based reporter system for real-time, live-cell quantification of Nrf2 activity in human melanoma cells. Utilizing live quantitative imaging, we dissected the kinetic profiles of Nrf2 activation in response to an array of stimuli, including UVA and UVB radiation, as well as a broad spectrum of phytochemicals including ferulic acid, gallic acid, hispidulin, p-coumaric acid, quercetin, resveratrol, tannic acid, and vanillic acid as well as well-known Nrf2 inducers, tert-butylhydroquinone (tBHQ) and sulforaphane (SFN). Intriguingly, we observed distinct dynamical patterns of Nrf2 activity contingent on the specific stimuli applied. Sustained activation of Nrf2 was empirically correlated with the increased antioxidant response element (ARE) activity. Our findings demonstrate the nuanced impact of different phenolic compounds on Nrf2 activity and the utility of our Nrf2-CTΔ16-YFP reporter in characterizing the dynamics of Nrf2 translocation in response to diverse stimuli. In summary, our innovative reporter system not only revealed compounds capable of modulating UVA-induced Nrf2 activity but also showcased its utility as a robust tool for future antioxidant compound screening efforts.
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Affiliation(s)
- Nilar Win Htut
- Department of Pharmacology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand; University of Medicine 2, Yangon, Khaymar Thi Rd, Yangon, Myanmar
| | - Tasanee Onkoksoong
- Department of Pharmacology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Malinee Saelim
- Department of Pharmacology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Patipark Kueanjinda
- Center of Excellence in Immunology and Immune-mediated Diseases, Division of Immunology, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Somponnat Sampattavanich
- Department of Pharmacology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand; Siriraj Center of Research Excellence (SiCORE) for Systems Pharmacology, Department of Pharmacology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Uraiwan Panich
- Department of Pharmacology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
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Ho DV, Suryajaya KG, Manh K, Duong AN, Chan JY. Characterization of NFE2L1-616, an isoform of nuclear factor-erythroid-2 related transcription factor-1 that activates antioxidant response element-regulated genes. Sci Rep 2023; 13:19900. [PMID: 37963997 PMCID: PMC10646089 DOI: 10.1038/s41598-023-47055-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 11/08/2023] [Indexed: 11/16/2023] Open
Abstract
The NFE2L1 transcription factor (aka Nrf1) is a basic leucine zipper protein that performs a critical role in the cellular stress response pathway. Here, we characterized a novel variant of NFE2L1 referred to as NFE2L1-616. The transcript encoding NFE2L1-616 is derived from an intronic promoter, and it has a distinct first exon than other reported full-length NFE2L1 isoforms. The NFE2L1-616 protein constitutively localizes in the nucleus as it lacks the N-terminal amino acid residues that targets other full-length NFE2L1 isoforms to the endoplasmic reticulum. The expression level of NFE2L1-616 is lower than other NFE2L1 isoforms. It is widely expressed across different cell lines and tissues that were examined. NFE2L1-616 showed strong transcriptional activity driving luciferase reporter expression from a promoter containing antioxidant response element. Together, the results suggest that NFE2L1-616 variant can function as a positive regulator in the transcriptional regulation of NFE2L1 responsive genes.
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Affiliation(s)
- Daniel V Ho
- Department of Laboratory Medicine and Pathology, University of California, Irvine, D440 Medical Sciences, Irvine, CA, 92697, USA
| | - Kaylen G Suryajaya
- Department of Laboratory Medicine and Pathology, University of California, Irvine, D440 Medical Sciences, Irvine, CA, 92697, USA
| | - Kaitlyn Manh
- Department of Laboratory Medicine and Pathology, University of California, Irvine, D440 Medical Sciences, Irvine, CA, 92697, USA
| | - Amanda N Duong
- Department of Laboratory Medicine and Pathology, University of California, Irvine, D440 Medical Sciences, Irvine, CA, 92697, USA
| | - Jefferson Y Chan
- Department of Laboratory Medicine and Pathology, University of California, Irvine, D440 Medical Sciences, Irvine, CA, 92697, USA.
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Gureev AP, Khorolskaya VG, Sadovnikova IS, Shaforostova EA, Cherednichenko VR, Burakova IY, Plotnikov EY, Popov VN. Age-Related Decline in Nrf2/ARE Signaling Is Associated with the Mitochondrial DNA Damage and Cognitive Impairments. Int J Mol Sci 2022; 23:ijms232315197. [PMID: 36499517 PMCID: PMC9739464 DOI: 10.3390/ijms232315197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 11/25/2022] [Accepted: 11/29/2022] [Indexed: 12/08/2022] Open
Abstract
In this research, we compared the cognitive parameters of 2-, 7-, and 15-month-old mice, changes in mitochondrial DNA (mtDNA) integrity and expression of genes involved in the nuclear erythroid 2-related factor 2/antioxidant response element (Nrf2/ARE) signaling pathway. We showed an age-related decrease in the Nfe2l2 expression in the cerebral cortex, not in the hippocampus. At the same time, we find an increase in the mtDNA copy number in the cerebral cortex, despite the lack of an increase in gene expression, which is involved in the mitochondrial biogenesis regulation. We suppose that increase in mtDNA content is associated with mitophagy downregulation. We supposed that mitophagy downregulation may be associated with an age-related increase in the mtDNA damage. In the hippocampus, we found a decrease in the Bdnf expression, which is involved in the pathways, which play an essential role in regulating long-term memory formation. We showed a deficit of working and reference memory in 15-month-old-mice in the water Morris maze, and a decrease in the exploratory behavior in the open field test. Cognitive impairments in 15-month-old mice correlated with a decrease in Bdnf expression in the hippocampus, Nfe2l2 expression, and an increase in the number of mtDNA damage in the cerebral cortex. Thus, these signaling pathways may be perspective targets for pharmacological intervention to maintain mitochondrial quality control, neuronal plasticity, and prevent the development of age-related cognitive impairment.
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Affiliation(s)
- Artem P. Gureev
- Department of Genetics, Cytology and Bioengineering, Voronezh State University, 394018 Voronezh, Russia
- Laboratory of Metagenomics and Food Biotechnology, Voronezh State University of Engineering Technologies, 394036 Voronezh, Russia
| | - Victoria G. Khorolskaya
- Department of Genetics, Cytology and Bioengineering, Voronezh State University, 394018 Voronezh, Russia
| | - Irina S. Sadovnikova
- Department of Genetics, Cytology and Bioengineering, Voronezh State University, 394018 Voronezh, Russia
| | - Ekaterina A. Shaforostova
- Department of Genetics, Cytology and Bioengineering, Voronezh State University, 394018 Voronezh, Russia
| | - Vadim R. Cherednichenko
- Department of Genetics, Cytology and Bioengineering, Voronezh State University, 394018 Voronezh, Russia
| | - Inna Y. Burakova
- Department of Genetics, Cytology and Bioengineering, Voronezh State University, 394018 Voronezh, Russia
- Laboratory of Metagenomics and Food Biotechnology, Voronezh State University of Engineering Technologies, 394036 Voronezh, Russia
| | - Egor Y. Plotnikov
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Russia
- Correspondence:
| | - Vasily N. Popov
- Department of Genetics, Cytology and Bioengineering, Voronezh State University, 394018 Voronezh, Russia
- Laboratory of Metagenomics and Food Biotechnology, Voronezh State University of Engineering Technologies, 394036 Voronezh, Russia
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Ebrahimy N, Gasterich N, Behrens V, Amini J, Fragoulis A, Beyer C, Zhao W, Sanadgol N, Zendedel A. Neuroprotective effect of the Nrf2/ARE/miRNA145-5p signaling pathway in the early phase of spinal cord injury. Life Sci 2022; 304:120726. [PMID: 35750202 DOI: 10.1016/j.lfs.2022.120726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 06/03/2022] [Accepted: 06/15/2022] [Indexed: 11/30/2022]
Abstract
AIMS Spinal cord injury (SCI) is a debilitating neurological condition often associated with chronic neuroinflammation and redox imbalance. Oxidative stress is one of the main hallmark of secondary injury of SCI which is tightly regulated by nuclear factor E2-related factor 2/antioxidant response element (Nrf2/ARE) signaling. In this study, we aimed at investigating the interplay between inflammation-related miRNAs and the Nrf2 pathway in animal model of SCI. MATERIALS AND METHODS The expression of selected four validated miRNA-target pairs (miRNA223-3p, miRNA155-5p, miRNA145-5p, and miRNA124-3p) was examined at different time points (6 h, 12 h, 1 day, 3 day and 7 day) after SCI. Further, using GFAP-specific kelch-like ECH-associated protein 1 deletion (Keap1-/-) and whole-body Nrf2-/- knockout mice, we investigated the potential interplay between each miRNA and the Keap1/Nrf2 signaling system. KEY FINDINGS The expression of all miRNAs except miRNA155-5p significantly increased 24 h after SCI and decreased after 7 days. Interestingly, Keap1-/- mice only showed significant increase in the miRNA145-5p after 24 h SCI compared to the WT group. In addition, Keap1-/- mice showed significant decrease in CXCL10/12 (CXCL12 increased in Nrf2-/- mice), and TNF-α, and an increase in Mn-SOD and NQO-1 (Mn-SOD and NQO-1 decreased in Nrf2-/- mice) compared to WT mice. SIGNIFICANCE Our results suggest that astrocytic hyperactivation of Nrf2 exert neuroprotective effects at least in part through the upregulation of miRNA145-5p, a negative regulator of astrocyte proliferation, and induction of ARE in early phase of SCI. Further studies are needed to investigate the potential interplay between Nrf2 and miRNA145-5p in neuroinflammatory condition.
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Affiliation(s)
- Nahal Ebrahimy
- Institute of Neuroanatomy, Uniklinik RWTH Aachen, Aachen, Germany
| | | | - Victoria Behrens
- Institute of Neuroanatomy, Uniklinik RWTH Aachen, Aachen, Germany
| | - Javad Amini
- Department of Medical Biotechnology and Molecular Science, North Khorasan University of Medical Science, Bojnurd, Iran
| | - Athanassios Fragoulis
- Department of Anatomy and Cell Biology, Uniklinik RWTH Aachen, 52074 Aachen, Germany
| | - Cordian Beyer
- Institute of Neuroanatomy, Uniklinik RWTH Aachen, Aachen, Germany
| | - Weiyi Zhao
- Institute of Neuroanatomy, Uniklinik RWTH Aachen, Aachen, Germany
| | - Nima Sanadgol
- Institute of Neuroanatomy, Uniklinik RWTH Aachen, Aachen, Germany
| | - Adib Zendedel
- Institute of Neuroanatomy, Uniklinik RWTH Aachen, Aachen, Germany.
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Wei Z, Zhao J, Zhang L, Xia M. Cell-Based Assays to Identify Modulators of Nrf2/ARE Pathway. Methods Mol Biol 2022; 2474:59-69. [PMID: 35294756 PMCID: PMC9438791 DOI: 10.1007/978-1-0716-2213-1_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The nuclear factor erythroid 2-related factor (Nrf2) and antioxidant response element (ARE) signaling pathway play an important role in the amelioration of cellular oxidative stress. Thus, assays that detect this pathway can be useful for identifying chemicals that induce or inhibit oxidative stress signaling. This chapter is to describe two cell-based Nrf2/ARE assays in a quantitative high-throughput screening (HTS) format to test a large collection of chemicals for oxidative stress induction ability. The assay descriptions involve cell handling, assay preparation, instrument usage, and assay procedure.
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Affiliation(s)
- Zhengxi Wei
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, USA
| | - Jinghua Zhao
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, USA
| | - Li Zhang
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, USA
| | - Menghang Xia
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, USA.
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Yuan M, Zhao B, Jia H, Zhang C, Zuo X. Sinomenine ameliorates cardiac hypertrophy by activating Nrf2/ARE signaling pathway. Bioengineered 2021; 12:12778-12788. [PMID: 34895050 PMCID: PMC8810090 DOI: 10.1080/21655979.2021.2000195] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 10/24/2021] [Accepted: 10/26/2021] [Indexed: 02/04/2023] Open
Abstract
Cardiac hypertrophy (CH) is a result of the physiological adaptation of the heart to coronary heart disease, hypertension, and other cardiovascular diseases. Sinomenine is extracted from Caulis Sinomenii. This study aimed to explore the specific mechanism of the action of sinomenine in cardiac hypertrophy (CH) via Nrf2/ARE signaling pathway in vivo and in vitro. To establish a model of CH, H9C2 cells were treated with angiotensin II (Ang II) and intraperitoneally injected with isoproterenol. Then the cells were treated with 50 and 100 μM sinomenine. TUNEL, HE, rhodamine-labeled phalloidin, and immunohistochemical staining were performed. Flow cytometry was used to measure apoptosis rates. mRNA expression of ANP, BNP, and β-MHC was determined by qRT-PCR. Furthermore, western blotting was performed to analyze protein expression. After sinomenine treatment, the surface area and apoptosis rates were decreased. Furthermore, the mRNA expression of ANP, BNP, and β-MHC, levels of reactive oxygen species and malondialdehyde, and protein expression of Caspase3 and Bax were down-regulated, and the protein expression of Bcl-2 was upregulated. Sinomenine activates the Nrf2/ARE signaling pathway, and inhibition of this signaling pathway reversed the effects of sinomenine. In animal experiments, sinomenine decreased the heart weight and left ventricular weight indices, as well as the expression of ANP, BNP, and β-MHC. Furthermore, sinomenine reduced the apoptosis rate and relieved CH-related oxidative stress by activating the Nrf2/ARE signaling pathway. Together, these findings reveal that sinomenine is a potential candidate drug for CH treatment and further research is required to generalize the result in human subjects.
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Affiliation(s)
- ManLi Yuan
- Department of Ultrasound Medicine, PLA Strategic Support Force Characteristic Medical Center, Beijing, People's Republic of China
| | - Bei Zhao
- Department of Cardiovascular Medicine, PLA Strategic Support Force Characteristic Medical Center, Beijing, People's Republic of China
| | - Huaping Jia
- Department of Ultrasound Medicine, PLA Strategic Support Force Characteristic Medical Center, Beijing, People's Republic of China
| | - Can Zhang
- Department of Ultrasound Medicine, PLA Strategic Support Force Characteristic Medical Center, Beijing, People's Republic of China
| | - Xiaowen Zuo
- Department of Ultrasound Medicine, PLA Strategic Support Force Characteristic Medical Center, Beijing, People's Republic of China
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Liu H, Johnston LJ, Wang F, Ma X. Triggers for the Nrf2/ARE Signaling Pathway and Its Nutritional Regulation: Potential Therapeutic Applications of Ulcerative Colitis. Int J Mol Sci 2021; 22:ijms222111411. [PMID: 34768841 PMCID: PMC8583850 DOI: 10.3390/ijms222111411] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 10/15/2021] [Accepted: 10/18/2021] [Indexed: 02/07/2023] Open
Abstract
Ulcerative colitis (UC), which affects millions of people worldwide, is characterized by extensive colonic injury involving mucosal and submucosal layers of the colon. Nuclear factor E2-related factor 2 (Nrf2) plays a critical role in cellular protection against oxidant-induced stress. Antioxidant response element (ARE) is the binding site recognized by Nrf2 and leads to the expression of phase II detoxifying enzymes and antioxidant proteins. The Nrf2/ARE system is a key factor for preventing and resolving tissue injury and inflammation in disease conditions such as UC. Researchers have proposed that both Keap1-dependent and Keap1-independent cascades contribute positive effects on activation of the Nrf2/ARE pathway. In this review, we summarize the present knowledge on mechanisms controlling the activation process. We will further review nutritional compounds that can modulate activation of the Nrf2/ARE pathway and may be used as potential therapeutic application of UC. These comprehensive data will help us to better understand the Nrf2/ARE signaling pathway and promote its effective application in response to common diseases induced by oxidative stress and inflammation.
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Affiliation(s)
- Hu Liu
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China; (H.L.); (F.W.)
| | - Lee J. Johnston
- Swine Nutrition and Production, West Central Research and Outreach Center, University of Minnesota, Morris, MN 56267, USA;
| | - Fenglai Wang
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China; (H.L.); (F.W.)
| | - Xi Ma
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China; (H.L.); (F.W.)
- Correspondence:
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Zhang D, Zhao Y, Wang J, Zhao P, Xu S. BRS1 mediates plant redox regulation and cold responses. BMC Plant Biol 2021; 21:268. [PMID: 34116634 PMCID: PMC8193866 DOI: 10.1186/s12870-021-03045-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 05/17/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Brassinosteroid-insensitive 1 suppressor 1 (BRS1) is a serine carboxypeptidase that mediates brassinosteroid signaling and participates in multiple developmental processes in Arabidopsis. However, little is known about the precise role of BRS1 in this context. RESULTS In this study, we analyzed transcriptional and proteomic profiles of Arabidopsis seedlings overexpressing BRS1 and found that this gene was involved in both cold stress responses and redox regulation. Further proteomic evidence showed that BRS1 regulated cell redox by indirectly interacting with cytosolic NADP + -dependent isocitrate dehydrogenase (cICDH). One novel alternative splice form of BRS1 was identified in over-expression mutants brs1-1D, which may confer a new role in plant development and stress responses. CONCLUSIONS This study highlights the role of BRS1 in plant redox regulation and stress responses, which extends our understanding of extracellular serine carboxypeptidases.
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Affiliation(s)
- Dongzhi Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Yuqian Zhao
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Junzhe Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Peng Zhao
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Shengbao Xu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100, Shaanxi, China.
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Zhang S, Khan WA, Su L, Zhang X, Li C, Qin W, Zhao Y. Predicting oxidative stress induced by organic chemicals by using quantitative Structure-Activity relationship methods. Ecotoxicol Environ Saf 2020; 201:110817. [PMID: 32512417 DOI: 10.1016/j.ecoenv.2020.110817] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/25/2020] [Accepted: 05/26/2020] [Indexed: 06/11/2023]
Abstract
Cellular exposure to xenobiotic human-made products will lead to oxidative stress that gives rise to DNA damage, as well as chemical or mechanical damage. Distinguishing the chemicals that will induce oxidative stress and predicting their toxicity is necessary. In the present study, 4270 compounds in the ARE-bla assay were investigated to predict active and inactive compounds by using simple algorithms, namely, recursive partitioning (RP) and binomial logistic regression, and to develop the quantitative structure-activity relationship (QSAR) models of chemicals that activate the ARE pathway to induce oxidative stress and exert toxic effects on cells. A decision tree based on scaffold-based fragments obtained through RP analysis showed the best identification accuracy. However, the overall identification accuracy of this model for active compounds was unsatisfactory due to limited fragments. Furthermore, a binomial logistic regression model was developed from 638 active compounds and 3632 inactive chemicals. The model with a cutoff of 0.15 could predict chemicals that were active or inactive with the prediction accuracy of 69.1%. Its area under the receiver operating characteristic (ROC) curve metric (AUROC) was 0.762, which indicated the acceptable predictive ability of this model. The parameters nBM (number of multiple bonds) and H% (percentage of H atom) played dominant roles in the prediction of the activity (inactive or active) of chemicals. A global QSAR model was developed to predict the toxicity of active chemicals. However, the model displayed an unsatisfactory result with R2 = 0.316 and R2ext = 0.090. Active chemicals were then classified on the basis of structure. A total of 79 compounds with carbon chains could be predicted with acceptable performance by using a QSAR model with six descriptors (R2 = 0.722, R2ext = 0.798, Q2Loo = 0.654, Q2Boot = 0.755, Q2ext = 0.721). The simple models established here contribute to efforts on identification compounds inducing oxidative stress and provide the scientific basis for risk assessment to organisms in the environment.
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Affiliation(s)
- Shengnan Zhang
- School of Environment, And State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, Northeast Normal University, 2555 Jingyue Street, Changchun, 130117, Jilin, PR China
| | - Waqas Amin Khan
- School of Environment, And State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, Northeast Normal University, 2555 Jingyue Street, Changchun, 130117, Jilin, PR China
| | - Limin Su
- School of Environment, And State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, Northeast Normal University, 2555 Jingyue Street, Changchun, 130117, Jilin, PR China.
| | - Xuehua Zhang
- School of Water Conservancy and Environment Engineering, Changchun Institute of Technology, Changchun, 130012, Jilin, PR China
| | - Chao Li
- School of Environment, And State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, Northeast Normal University, 2555 Jingyue Street, Changchun, 130117, Jilin, PR China
| | - Weichao Qin
- School of Environment, And State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, Northeast Normal University, 2555 Jingyue Street, Changchun, 130117, Jilin, PR China
| | - Yuanhui Zhao
- School of Environment, And State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, Northeast Normal University, 2555 Jingyue Street, Changchun, 130117, Jilin, PR China
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Gupta A, Gupta G, Mehta RR, Ivancic DZ, Walker RR, Patel JR, Gallegos KM, Davidson AM, Khan SA, Mehta RG, Tilghman SL. A novel and cost-effective ex vivo orthotopic model for the study of human breast cancer in mouse mammary gland organ culture. Biol Open 2020; 9:bio051649. [PMID: 32366373 PMCID: PMC7272353 DOI: 10.1242/bio.051649] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 04/09/2020] [Indexed: 12/16/2022] Open
Abstract
Mouse mammary organ culture (MMOC) is used to evaluate the efficacy of chemopreventive agents against the development of carcinogen-induced preneoplastic lesions and is highly correlative to in vivo carcinogenesis models. Here, we developed a new ex vivo MMOC model, by introducing human breast cancer cells into the mouse mammary gland. This novel model, termed human breast cancer in MMOC (BCa-MMOC), mimics in vivo orthotopic breast cancer mouse models. To develop this model, estradiol- and progesterone-sensitized female mice were injected with letrozole-sensitive and -resistant T47D breast cancer cells in the mammary glands and then euthanized. The glands were cultured in vitro with hormone-supplemented media. On day 25, the glands were fixed and processed by histopathology and immunohistochemistry to evaluate for the presence of T47D cells, growth pattern, cancer markers and estradiol responsiveness. Histopathological analyses demonstrated an identical pattern of growth between the breast cancer cells injected ex vivo and in vivo Interestingly, clusters of cancer cells in the mammary gland stroma appeared similar to those observed in human breast tumors. The injected T47D cells survived and proliferated for 15 days maintaining expression of estrogen receptor alpha (ER), progesterone receptor (PR), epidermal growth factor receptor (EGFR), and aromatase. The aromatase-overexpressing T47D grown in the BCa-MMOC sufficiently metabolized estrogen, resulting in enhanced cell proliferation, induction of estrogen target genes (i.e. ER and PR-B), and showed typical changes to estrogenic milieu. In summary, here we show a novel, inexpensive ex vivo model, to potentially study the effects of therapeutic agents on cancer cells grown in an orthotopic micromilieu.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Akash Gupta
- Department of Medicine, University of Arizona, Tucson, AZ 85724, USA
| | - Geetanjali Gupta
- Department of Medicine, University of Arizona, Tucson, AZ 85724, USA
| | | | - David Z Ivancic
- Department of Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Rashidra R Walker
- Division of Basic Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA
| | - Jankiben R Patel
- Division of Basic Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA
| | - Karen M Gallegos
- Division of Basic Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA
| | - A Michael Davidson
- Division of Basic Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA
| | - Seema A Khan
- Department of Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Rajendra G Mehta
- Cancer Biology Division, IIT Research Institute, Chicago, IL 60616, USA
| | - Syreeta L Tilghman
- Division of Basic Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA
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Ramprasath T, Freddy AJ, Velmurugan G, Tomar D, Rekha B, Suvekbala V, Ramasamy S. Context-Dependent Regulation of Nrf2/ARE Axis on Vascular Cell Function during Hyperglycemic Condition. Curr Diabetes Rev 2020; 16:797-806. [PMID: 32000646 DOI: 10.2174/1573399816666200130094512] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 12/03/2019] [Accepted: 12/26/2019] [Indexed: 12/13/2022]
Abstract
Diabetes mellitus is associated with an increased risk of micro and macrovascular complications. During hyperglycemic conditions, endothelial cells and vascular smooth muscle cells are exquisitely sensitive to high glucose. This high glucose-induced sustained reactive oxygen species production leads to redox imbalance, which is associated with endothelial dysfunction and vascular wall remodeling. Nrf2, a redox-regulated transcription factor plays a key role in the antioxidant response element (ARE)-mediated expression of antioxidant genes. Although accumulating data indicate the molecular mechanisms underpinning the Nrf2 regulated redox balance, understanding the influence of the Nrf2/ARE axis during hyperglycemic condition on vascular cells is paramount. This review focuses on the context-dependent role of Nrf2/ARE signaling on vascular endothelial and smooth muscle cell function during hyperglycemic conditions. This review also highlights improving the Nrf2 system in vascular tissues, which could be a potential therapeutic strategy for vascular dysfunction.
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Affiliation(s)
- Tharmarajan Ramprasath
- Department of Molecular Biology, School of Biological Sciences, Madurai Kamaraj University, Madurai 625021, Tamil Nadu, India
| | - Allen John Freddy
- Department of Zoology, Madras Christian College, Chennai 600 059, Tamil Nadu, India
| | - Ganesan Velmurugan
- Chemomicrobiomics Laboratory, KMCH Research Foundation, Kovai Medical Center & Hospital, Coimbatore 641 014, Tamil Nadu, India
| | - Dhanendra Tomar
- Center for Translational Medicine, Temple University, Philadelphia 19140, United States
| | - Balakrishnan Rekha
- Department of Molecular Biology, School of Biological Sciences, Madurai Kamaraj University, Madurai 625021, Tamil Nadu, India
| | - Vemparthan Suvekbala
- Department of Biomedical Sciences & Technology, Noorul Islam Centre for Higher Education, Kumaracoil, Thucklay, Tamilnadu 629180, India
| | - Subbiah Ramasamy
- Department of Molecular Biology, School of Biological Sciences, Madurai Kamaraj University, Madurai 625021, Tamil Nadu, India
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12
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Zhu Y, Ren C, Zhang M, Zhong Y. Perilipin 5 Reduces Oxidative Damage Associated With Lipotoxicity by Activating the PI3K/ERK-Mediated Nrf2-ARE Signaling Pathway in INS-1 Pancreatic β-Cells. Front Endocrinol (Lausanne) 2020; 11:166. [PMID: 32296390 PMCID: PMC7136399 DOI: 10.3389/fendo.2020.00166] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 03/09/2020] [Indexed: 12/16/2022] Open
Abstract
Oxidative stress induced by free fatty acid overload in pancreatic β-cells is a potential contributory factor to dysfunction of insulin secretion and apoptotic cell death. Perilipin 5 (Plin5) has been reported to ameliorate oxidative stress-mediated damage in non-insulin-secreting tissues. We tested the hypothesis that Plin5 plays a similar role in pancreatic β-cells, which are extremely sensitive to oxidative stress. Here, our in vitro data showed that Plin5-mediated alleviation of palmitate-triggered apoptosis involves the mitochondrial pathway. And the protective role of Plin5 on β-cells was partially dependent on its modulation in oxidative stress. Upregulation of Plin5 in INS-1 cells decreased reactive oxygen species production, enhanced cellular glutathione levels, and induced expression of antioxidant enzymes glutamate-cysteine ligase catalytic subunit and heme oxygenase-1. However, knocking out of Plin5 abolished all of these beneficial effects. Furthermore, by using the O2- scavenger MnTMPyP, we verified that altering Plin5 expression impacted lipotoxic cell death partially via modulating oxidative stress. Mechanistic experiments revealed that Plin5 induced Nrf2-ARE system, a master regulator in the cellular adaptive response to oxidative stress, by activating PI3K/Akt and ERK signal pathways, contributing to the increase of antioxidant defense and consequently improving β-cell function and survival in the presence of lipotoxic oxidative stress. Overall, our findings indicate that Plin5 abrogates oxidative damage in INS-1 β-cells during lipotoxic stress partially through the enhancement of antioxidant defense involving the PI3K/Akt and ERK mediated Nrf2-ARE system.
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Affiliation(s)
- Yunxia Zhu
- Department of Geriatrics, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- *Correspondence: Yunxia Zhu
| | - Chenxi Ren
- Department of Geriatrics, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Mingliang Zhang
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Yuan Zhong
- Department of Geriatrics, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
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13
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Mourabit S, Fitzgerald JA, Ellis RP, Takesono A, Porteus CS, Trznadel M, Metz J, Winter MJ, Kudoh T, Tyler CR. New insights into organ-specific oxidative stress mechanisms using a novel biosensor zebrafish. Environ Int 2019; 133:105138. [PMID: 31645010 DOI: 10.1016/j.envint.2019.105138] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 08/08/2019] [Accepted: 08/27/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Reactive oxygen species (ROS) arise as a result from, and are essential in, numerous cellular processes. ROS, however, are highly reactive and if left unneutralised by endogenous antioxidant systems, can result in extensive cellular damage and/or pathogenesis. In addition, exposure to a wide range of environmental stressors can also result in surplus ROS production leading to oxidative stress (OS) and downstream tissue toxicity. OBJECTIVES Our aim was to produce a stable transgenic zebrafish line, unrestricted by tissue-specific gene regulation, which was capable of providing a whole organismal, real-time read-out of tissue-specific OS following exposure to a wide range of OS-inducing environmental contaminants and conditions. This model could, therefore, serve as a sensitive and specific mechanistic in vivo biomarker for all environmental conditions that result in OS. METHODS To achieve this aim, we exploited the pivotal role of the electrophile response element (EpRE) as a globally-acting master regulator of the cellular response to OS. To test tissue specificity and quantitative capacity, we selected a range of chemical contaminants known to induce OS in specific organs or tissues, and assessed dose-responsiveness in each using microscopic measures of mCherry fluorescence intensity. RESULTS We produced the first stable transgenic zebrafish line Tg (3EpRE:hsp70:mCherry) with high sensitivity for the detection of cellular RedOx imbalances, in vivo in near-real time. We applied this new model to quantify OS after exposure to a range of environmental conditions with high resolution and provided quantification both of compound- and tissue-specific ROS-induced toxicity. DISCUSSION Our model has an extremely diverse range of potential applications not only for biomonitoring of toxicants in aqueous environments, but also in biomedicine for identifying ROS-mediated mechanisms involved in the progression of a number of important human diseases, including cancer.
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Affiliation(s)
- Sulayman Mourabit
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK.
| | | | - Robert P Ellis
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Aya Takesono
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Cosima S Porteus
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Maciej Trznadel
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Jeremy Metz
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Matthew J Winter
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Tetsuhiro Kudoh
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Charles R Tyler
- Biosciences, College of Life and Environmental Sciences, University of Exeter, UK.
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14
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Kapetanaki MG, Gbotosho OT, Sharma D, Weidert F, Ofori-Acquah SF, Kato GJ. Free heme regulates placenta growth factor through NRF2-antioxidant response signaling. Free Radic Biol Med 2019; 143:300-308. [PMID: 31408727 PMCID: PMC6848791 DOI: 10.1016/j.freeradbiomed.2019.08.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 08/01/2019] [Accepted: 08/07/2019] [Indexed: 12/17/2022]
Abstract
Free heme activates erythroblasts to express and secrete Placenta Growth Factor (PlGF), an angiogenic peptide of the VEGF family. High circulating levels of PlGF have been associated in experimental animals and in patients with sickle cell disease with echocardiographic markers of pulmonary hypertension, a life-limiting complication associated with more intense hemolysis. We now show that the mechanism of heme regulation of PlGF requires the contribution of the key antioxidant response regulator NRF2. Mimicking the effect of heme, the NRF2 agonist sulforaphane stimulates the PlGF transcript level nearly 30-fold in cultured human erythroblastoid cells. Heme and sulforaphane also induce transcripts for NRF2 itself, its partners MAFF and MAFG, and its competitor BACH1. Furthermore, heme induction of the PlGF transcript is significantly diminished by the NRF2 inhibitor brusatol and by siRNA knockdown of the NRF2 and/or MAFG transcription factors. Chromatin immunoprecipitation experiments show that heme induces NRF2 to bind directly to the PlGF promoter region. In complementary in vivo experiments, mice injected with heme show a significant increase in their plasma PlGF protein as early as 3 h after treatment. Our results reveal an important mechanism of PlGF regulation, adding to the growing literature that supports the pivotal importance of the NRF2 axis in the pathobiology of sickle cell disease.
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Affiliation(s)
- Maria G Kapetanaki
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Pittsburgh Heart, Lung, Blood, and Vascular Medicine Institute, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Oluwabukola T Gbotosho
- Division of Hematology-Oncology, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Pittsburgh Heart, Lung, Blood, and Vascular Medicine Institute, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Deva Sharma
- Division of Hematology-Oncology, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Pittsburgh Heart, Lung, Blood, and Vascular Medicine Institute, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Frances Weidert
- Pittsburgh Heart, Lung, Blood, and Vascular Medicine Institute, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Solomon F Ofori-Acquah
- Division of Hematology-Oncology, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Pittsburgh Heart, Lung, Blood, and Vascular Medicine Institute, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Center for Translational and International Hematology, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Gregory J Kato
- Division of Hematology-Oncology, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Pittsburgh Heart, Lung, Blood, and Vascular Medicine Institute, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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15
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Jin A, Li B, Li W, Xiao D. PHLPP2 downregulation protects cardiomyocytes against hypoxia-induced injury through reinforcing Nrf2/ARE antioxidant signaling. Chem Biol Interact 2019; 314:108848. [PMID: 31610156 DOI: 10.1016/j.cbi.2019.108848] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Revised: 09/19/2019] [Accepted: 10/09/2019] [Indexed: 11/18/2022]
Abstract
Cardiomyocyte injury induced by acute myocardial infarction contributes to myocardial dysfunction. Accumulating evidence has demonstrated that pleckstrin homology domain leucine-rich repeat protein phosphatase 2 (PHLPP2) is a cytoprotective protein that protects against various adverse injuries. However, whether PHLPP2 participates in regulating myocardial-infarction-induced cardiomyocyte injury remains unknown. In the present study, we aimed to investigate the biological role and molecular mechanism of PHLPP2 in regulating hypoxia-induced cardiomyocyte injury. Cardiomyocytes were cultured in an anaerobic chamber for 24 h to induce hypoxic injury in vitro. The expression of PHLPP2 was determined by real-time quantitative PCR and Western blot analysis. Cell viability was measured by MTT assay. Cell apoptosis was assessed by TUNEL and caspase-3 activity assays. Intracellular reactive oxygen species (ROS) levels were measured by DCFH-DA probe. PHLPP2 expression was highly upregulated in hypoxia-injured cardiomyocytes. Inhibition of PHLPP2 by small interfering RNA (siRNA)-mediated gene silencing significantly improved the viability of hypoxia-injured cardiomyocytes and attenuated hypoxia-induced apoptosis and ROS production. In contrast, PHLPP2 overexpression exacerbated hypoxia-induced apoptosis and ROS production in cardiomyocytes. Mechanism research revealed that PHLPP2 silencing increased the phosphorylation of glycogen synthase kinase (GSK)-3β and promoted the nuclear translocation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2). In addition, PHLPP2 inhibition promoted Nrf2/antioxidant response element (ARE) transcriptional activity. However, Nrf2 silencing markedly reversed PHLPP2-inhibition-mediated cardioprotection, while GSK-3β inhibition partially blocked the PHLPP2-overexpression-induced adverse effect. Taken together, these findings demonstrate that PHLPP2 inhibition alleviates hypoxia-induced cardiomyocyte injury by reinforcing Nrf2/ARE antioxidant signaling via inactivating GSK-3β, a pathway that highlights the importance of the PHLPP2/GSK-3β/Nrf2/ARE signaling axis in regulation of cardiomyocyte injury. Our study suggests a potential relevance for PHLPP2 in acute myocardial infarction, and this protein may serve as a promising target for cardioprotection.
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Affiliation(s)
- Aiping Jin
- Geriatric Cardiovascular Department, The Second Affiliated Hospital of Xi'an Jiaotong University (Xibei Hospital), No. 157, Xiwu Road, Xi'an, 710004, Shaanxi Province, China.
| | - Bing Li
- Geriatric Cardiovascular Department, The Second Affiliated Hospital of Xi'an Jiaotong University (Xibei Hospital), No. 157, Xiwu Road, Xi'an, 710004, Shaanxi Province, China
| | - Wei Li
- Geriatric Cardiovascular Department, The Second Affiliated Hospital of Xi'an Jiaotong University (Xibei Hospital), No. 157, Xiwu Road, Xi'an, 710004, Shaanxi Province, China
| | - Dan Xiao
- Geriatric Cardiovascular Department, The Second Affiliated Hospital of Xi'an Jiaotong University (Xibei Hospital), No. 157, Xiwu Road, Xi'an, 710004, Shaanxi Province, China
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16
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Yang B, Yin C, Zhou Y, Wang Q, Jiang Y, Bai Y, Qian H, Xing G, Wang S, Li F, Feng Y, Zhang Y, Cai J, Aschner M, Lu R. Curcumin protects against methylmercury-induced cytotoxicity in primary rat astrocytes by activating the Nrf2/ARE pathway independently of PKCδ. Toxicology 2019; 425:152248. [PMID: 31330227 PMCID: PMC6710134 DOI: 10.1016/j.tox.2019.152248] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 07/07/2019] [Accepted: 07/18/2019] [Indexed: 12/11/2022]
Abstract
Methylmercury (MeHg) is a ubiquitous environmental toxicant that leads to long-lasting neurological deficits in animals and humans. Curcumin, a polyphenol obtained from the rhizome of turmeric, has well-known antioxidant functions. Here, we evaluated curcumin's efficacy in mitigating MeHg-induced cytotoxicity and further investigated the underlying mechanism of this neuroprotection in primary rat astrocytes. Pretreatment with curcumin (2, 5, 10 and 20 μM for 3, 6, 12 or 24 h) protected against MeHg-induced (5 μM for 6 h) cell death in a time and dose-dependent manner. Curcumin (2, 5, 10 or 20 μM) pretreatment for 12 h significantly ameliorated the MeHg-induced astrocyte injury and oxidative stress, as evidenced by morphological alterations, lactate dehydrogenase (LDH) release, reactive oxygen species (ROS) generation, and glutathione (GSH) and catalase (CAT) levels. Moreover, curcumin pretreatment increased Nrf2 nuclear translocation and downstream enzyme expression, heme oxygenase-1 (HO-1) and NADPH quinone reductase-1 (NQO1). Knockdown of Nrf2 with siRNA attenuated the protective effect of curcumin against MeHg-induced cell death. However, both the pan-protein kinase C (PKC) inhibitor, Ro 31-8220, and the selective PKCδ inhibitor, rottlerin, failed to suppress the curcumin-activated Nrf2/Antioxidant Response Element(ARE) pathway and attenuate the protection exerted by curcumin. Taken together, these findings confirm that curcumin protects against MeHg-induced neurotoxicity by activating the Nrf2/ARE pathway and this protection is independent of PKCδ activation. More studies are needed to understand the mechanisms of curcumin cytoprotection.
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Affiliation(s)
- Bobo Yang
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Changsheng Yin
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China; Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Yun Zhou
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Qiang Wang
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Yuanyue Jiang
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Yu Bai
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Hai Qian
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Guangwei Xing
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Suhua Wang
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Fang Li
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Yun Feng
- Department of Pharmacology, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Yubin Zhang
- Department of Occupational Health and Toxicology, School of Public Health, Fudan University, Shanghai 200032, China
| | - Jiyang Cai
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, Galveston, TX 77550-1106, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Rongzhu Lu
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, Jiangsu 212013, China; Center for Experimental Research, Kunshan Hospital Affiliated to Jiangsu University, Kunshan, Jiangsu 215132, China.
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17
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Lu K, Cheng Y, Li W, Ni H, Chen X, Li Y, Tang B, Li Y, Chen D, Zeng R, Song Y. Copper-induced H 2O 2 accumulation confers larval tolerance to xanthotoxin by modulating CYP6B50 expression in Spodoptera litura. Pestic Biochem Physiol 2019; 159:118-126. [PMID: 31400773 DOI: 10.1016/j.pestbp.2019.06.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 05/30/2019] [Accepted: 06/04/2019] [Indexed: 05/12/2023]
Abstract
In the plant-insect arms race, plants synthesize toxic compounds to defend against herbivorous insects, whereas insects employ cytochrome P450 monooxygenases (P450s) to detoxify these phytotoxins. As ubiquitous environmental contaminants, heavy metals can be easily absorbed by plants and further accumulated in herbivorous insects through the food chains, resulting in tangible consequences for plant-insect interactions. However, whether heavy metals can influence P450 activities and thereby cause further effects on larval tolerance to phytotoxins remains unknown. In this study, we shown that prior exposure to copper (Cu) enhanced larval tolerance to xanthotoxin in Spodoptera litura, a major polyphagous pest of agriculture. P450 activities were induced in larvae exposed to Cu or xanthotoxin, and a midgut specific expressed P450 gene, CYP6B50 was cross-induced after exposure to these two toxic xenobiotics. Knocking down CYP6B50 by RNA interference (RNAi) rendered the larvae more sensitive to xanthotoxin. As defense against oxidative stress following metal exposure has been demonstrated to affect insecticide resistance, the reactive oxygen species (ROS) generation and antioxidant enzyme activities were assessed. Cu exposure caused the accumulation of hydrogen peroxide (H2O2) and enhanced the activities of superoxide dismutase (SOD) and peroxidase (POD) in larval midgut. In addition, two antioxidant response elements (AREs) were identified from the CYP6B50 promoter, indicating that Cu-induced CYP6B50 expression may be related to the ROS burst. Application of ROS scavenger N-acetylcysteine (NAC) effectively suppressed CYP6B50 expression, inhibited P450 activities and impaired larval tolerance to xanthotoxin that had been induced by Cu. These results indicate that the increase in CYP6B50 expression regulated by Cu-induced H2O2 generation contributed to the enhancement of larval tolerance to xanthotoxin in S. litura. Ingestion of heavy metals from their host plants can inadvertently boost the counter-defense system of herbivorous insects to protect themselves against plant defensive toxins.
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Affiliation(s)
- Kai Lu
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Yibei Cheng
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Wenru Li
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Hanfang Ni
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Xia Chen
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Yue Li
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Bingjie Tang
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Yimin Li
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Dongmei Chen
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Rensen Zeng
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Yuanyuan Song
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
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Simenauer A, Assefa B, Rios-Ochoa J, Geraci K, Hybertson B, Gao B, McCord J, Elajaili H, Nozik-Grayck E, Cota-Gomez A. Repression of Nrf2/ARE regulated antioxidant genes and dysregulation of the cellular redox environment by the HIV Transactivator of Transcription. Free Radic Biol Med 2019; 141:244-252. [PMID: 31238128 PMCID: PMC7096131 DOI: 10.1016/j.freeradbiomed.2019.06.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 06/11/2019] [Accepted: 06/11/2019] [Indexed: 11/17/2022]
Abstract
Chronic HIV infection in the era of anti-retroviral therapy is associated with dramatically increased risk of developing severe cardio pulmonary disease. Common to these diseases is increased oxidative burden and chronic inflammation despite low viremia and restoration of CD4+ T-cell levels. Soluble viral factors are heavily implicated in these disease processes, including the HIV Transactivator of Transcription (Tat). Tat is produced in high levels during infection and secreted from infected cells into circulation where it is internalized by bystander cells and is known to regulate inflammatory pathways and elicit a pro-oxidant environment. We have examined the effects of Tat on the anti-oxidant regulatory network driven by the transcription factor Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) in primary human pulmonary arterial endothelial cells, which are heavily involved in pathogenesis of HIV associated lung diseases including pulmonary arterial hypertension and COPD. Co-expression of Tat and a luciferase reporter construct driven by the Nrf2 activated anti-oxidant response element (ARE) demonstrated markedly reduced Nrf2/ARE activity, even when stimulated by the potent Nrf2 activating compound PB125. Additionally, Heme-oxygenase-1 (HO-1) transcription was potently repressed by Tat in a cell line as well as primary endothelial cells, and treatment with PB125 failed to restore transcriptional activity. Other anti-oxidant Nrf2 genes examined included NADPH Dehydrogenase Quinone 1 (NQO1) and Sulfiredoxin-1 (SRXN1). NQO1 was repressed basally by Tat, while SRXN1 transcription was refractory to activation by PB125 in the presence of Tat. Lastly, we demonstrated that Tat expressing cells have increased indicators of oxidative stress including elevated production of reactive oxygen species, measured by electron paramagnetic resonance spectroscopy, and increased levels of nitrotyrosine content. These observations suggest a novel mechanism by which HIV Tat increases oxidative burden by dysregulation of the Nrf2/ARE pathway.
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Affiliation(s)
- Ari Simenauer
- University of Colorado Anschutz Medical Campus, Department of Medicine Division of Pulmonary Sciences and Critical Care Medicine, 12700 E. 19th Avenue, Mailstop C272, 80045, Aurora, CO, USA
| | - Betelhem Assefa
- University of Colorado Anschutz Medical Campus, Department of Medicine Division of Pulmonary Sciences and Critical Care Medicine, 12700 E. 19th Avenue, Mailstop C272, 80045, Aurora, CO, USA
| | - Jose Rios-Ochoa
- University of Colorado Anschutz Medical Campus, Department of Medicine Division of Pulmonary Sciences and Critical Care Medicine, 12700 E. 19th Avenue, Mailstop C272, 80045, Aurora, CO, USA
| | - Kara Geraci
- University of Colorado Anschutz Medical Campus, Department of Medicine Division of Pulmonary Sciences and Critical Care Medicine, 12700 E. 19th Avenue, Mailstop C272, 80045, Aurora, CO, USA
| | - Brooks Hybertson
- University of Colorado Anschutz Medical Campus, Department of Medicine Division of Pulmonary Sciences and Critical Care Medicine, 12700 E. 19th Avenue, Mailstop C272, 80045, Aurora, CO, USA; Pathways Bioscience, USA
| | - Bifeng Gao
- University of Colorado Anschutz Medical Campus, Department of Medicine Division of Pulmonary Sciences and Critical Care Medicine, 12700 E. 19th Avenue, Mailstop C272, 80045, Aurora, CO, USA; Pathways Bioscience, USA
| | - Joe McCord
- University of Colorado Anschutz Medical Campus, Department of Medicine Division of Pulmonary Sciences and Critical Care Medicine, 12700 E. 19th Avenue, Mailstop C272, 80045, Aurora, CO, USA; Pathways Bioscience, USA
| | - Hanan Elajaili
- University of Colorado Anschutz Medical Campus, Department of Pediatrics, Cardiovascular Pulmonary Research Labs and Pediatric Critical Care Medicine, University of Colorado Denver, Pediatric Critical Care Medicine, Box B131, 12700 E. 19th Avenue, Research 2, Room, 6121, USA
| | - Eva Nozik-Grayck
- University of Colorado Anschutz Medical Campus, Department of Pediatrics, Cardiovascular Pulmonary Research Labs and Pediatric Critical Care Medicine, University of Colorado Denver, Pediatric Critical Care Medicine, Box B131, 12700 E. 19th Avenue, Research 2, Room, 6121, USA
| | - Adela Cota-Gomez
- University of Colorado Anschutz Medical Campus, Department of Medicine Division of Pulmonary Sciences and Critical Care Medicine, 12700 E. 19th Avenue, Mailstop C272, 80045, Aurora, CO, USA.
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Young Park S, Jin Kim Y, Park G, Kim HH. Neuroprotective effect of Dictyopteris divaricata extract-capped gold nanoparticles against oxygen and glucose deprivation/reoxygenation. Colloids Surf B Biointerfaces 2019; 179:421-428. [PMID: 31003168 DOI: 10.1016/j.colsurfb.2019.03.066] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/26/2019] [Accepted: 03/28/2019] [Indexed: 12/11/2022]
Abstract
Combination therapy remains a promising approach to ameliorate cerebral ischemia injury. Nevertheless, the primary mechanism of the neuroprotective properties of Dictyopteris divaricata extract-capped gold nanoparticles (DD-GNPs) is not completely understood. DD-GNPs displayed maximum absorption at 525 nm and a diameter of 62.6 ± 1.2 nm, with a zeta potential value of -26.1 ± 0.6 mV. High resolution-transmission electron microscopy confirmed the spherical shape and average diameter (28.01 ± 2.03 nm). Crystalline structure and gold nanoparticle synthesis of DD-GNPs were determined by X-ray powder diffraction, and the presence of elemental gold was confirmed by energy-dispersive X-ray spectroscopy and Fourier transform-infrared spectroscopy. We examined the neuroprotective properties of DD-GNPs and explored their potential mechanisms in human SH-SY5Y neuroblastoma cells treated with oxygen and glucose deprivation/reoxygenation (OGD/R). We found that DD-GNPs inhibited OGD/R-induced release of lactate dehydrogenase (LDH), loss of cell viability, and production of reactive oxygen species. This neuroprotection was accompanied by regulation of apoptosis-related proteins, as indicated by decreased levels of cleaved-caspase-3, cleaved-PARP, cleaved-caspase-9, p53, p21, and Bax, as well as an increased level of Bcl-2. Notably, the neuroprotective effects of DD-GNPs were partially abolished by HO-1, NQO1, Nrf2, and AMPK knockdown. Our results established that DD-GNPs effectively attenuated OGD/R-stimulated neuronal injury, as evidenced by reduced neuronal injury. Even though the accumulating evidence has indicated the low toxicity and minimal side effects of GNPs, experimental clinical trials of DD-GNPs are still limited because of the lack of knowledge regarding the effects of DD-GNPs as neuroprotective agents against neurodegenerative diseases.
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Affiliation(s)
- Sun Young Park
- Bio-IT Fusion Technology Research Institute, Pusan National University, Busan 46241, Republic of Korea
| | - Yeong Jin Kim
- Biomedical Research Institute, Pusan National University Hospital, Busan 49241, Republic of Korea
| | - Geuntae Park
- Department of Nanomaterials Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Hyung-Hoi Kim
- Biomedical Research Institute, Pusan National University Hospital, Busan 49241, Republic of Korea; Department of Laboratory Medicine, Pusan National University Hospital, Busan 49241, Republic of Korea
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20
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Zhang Y, Ahmad KA, Khan FU, Yan S, Ihsan AU, Ding Q. Chitosan oligosaccharides prevent doxorubicin-induced oxidative stress and cardiac apoptosis through activating p38 and JNK MAPK mediated Nrf2/ARE pathway. Chem Biol Interact 2019; 305:54-65. [PMID: 30928397 DOI: 10.1016/j.cbi.2019.03.027] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 03/14/2019] [Accepted: 03/26/2019] [Indexed: 11/19/2022]
Abstract
Doxorubicin (DOX) is one of the most effective chemotherapeutic drugs; however, the incidence of cardiotoxicity compromises its therapeutic index. Oxidative stress and apoptosis are believed to be involved in DOX-induced cardiotoxicity. Chitosan oligosaccharides (COS), the enzymatic hydrolysates of chitosan, have been reported to possess diverse biological activities including antioxidant and anti-apoptotic properties. The objective of the present study was to investigate the potential role of COS against DOX-induced cardiotoxicity, and the effects of COS on apoptosis and oxidative stress in rats and H9C2 cells. Furthermore, we also shed light on the involved pathways during the whole process. For this purpose, first, we demonstrated that COS exhibited a significant protective effect on cardiac tissue by not only inducing a decrease in body and heart growth but also ameliorated oxidative damage and ECG alterations in DOX-treated rats. Second, we found that COS reversed the decrease of cell viability induced by DOX, reduced the intracellular reactive oxygen species (ROS), increased the mitochondrial membrane potential (MMP) and Bcl-2/Bax ratio. COS treatment also results in reduced caspase-3 and caspase-9 expressions, and an increase in the phosphorylation of MAPKs (mitogen-activated protein kinases) in DOX-exposed H9C2 cells. Additionally, cellular homeostasis was re-established via stabilization of MAPK mediated nuclear factor erythroid 2-related factor 2/antioxidant-response element (Nrf2/ARE) signaling and transcription of downstream cytoprotective genes. In summary, these findings suggest that COS could be a potential candidate for the prevention and treatment of DOX-induced cardiotoxicity.
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Affiliation(s)
- Yongtian Zhang
- Experimental and Teaching Center of Medical Basis for Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Khalil Ali Ahmad
- Experimental and Teaching Center of Medical Basis for Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu, China; Shanghai Jiao Tong University, School of Pharmacy, 800 Dongchuan Road, Shanghai, 200240, China
| | - Farhan Ullah Khan
- Shanghai Jiao Tong University, School of Pharmacy, 800 Dongchuan Road, Shanghai, 200240, China; Department of Clinical Pharmacy, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu Province, 211198, China
| | - Simin Yan
- Experimental and Teaching Center of Medical Basis for Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Awais Ullah Ihsan
- Department of Clinical Pharmacy, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu Province, 211198, China
| | - Qilong Ding
- Experimental and Teaching Center of Medical Basis for Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu, China.
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Benkafadar N, François F, Affortit C, Casas F, Ceccato JC, Menardo J, Venail F, Malfroy-Camine B, Puel JL, Wang J. ROS-Induced Activation of DNA Damage Responses Drives Senescence-Like State in Postmitotic Cochlear Cells: Implication for Hearing Preservation. Mol Neurobiol 2019; 56:5950-5969. [PMID: 30693443 PMCID: PMC6614136 DOI: 10.1007/s12035-019-1493-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 01/11/2019] [Indexed: 12/20/2022]
Abstract
In our aging society, age-related hearing loss (ARHL) has become a major socioeconomic issue. Reactive oxygen species (ROS) may be one of the main causal factors of age-related cochlear cell degeneration. We examined whether ROS-induced DNA damage response drives cochlear cell senescence and contributes to ARHL from the cellular up to the system level. Our results revealed that sublethal concentrations of hydrogen peroxide (H2O2) exposure initiated a DNA damage response illustrated by increased γH2AX and 53BP1 expression and foci formation mainly in sensory hair cells, together with increased levels of p-Chk2 and p53. Interestingly, postmitotic cochlear cells exposed to H2O2 displayed key hallmarks of senescent cells, including dramatically increased levels of p21, p38, and p-p38 expression, concomitant with decreased p19 and BubR1 expression and positive senescence-associated β-galactosidase labeling. Importantly, the synthetic superoxide dismutase/catalase mimetic EUK-207 attenuated H2O2-induced DNA damage and senescence phenotypes in cochlear cells in vitro. Furthermore, systemic administration of EUK-207 reduced age-related loss of hearing and hair cell degeneration in senescence-accelerated mouse-prone 8 (SAMP8) mice. Altogether, these findings highlight that ROS-induced DNA damage responses drive cochlear cell senescence and contribute to accelerated ARHL. EUK-207 and likely other antioxidants with similar mechanisms of action could potentially postpone cochlear aging and prevent ARHL in humans.
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Affiliation(s)
- Nesrine Benkafadar
- INSERM - UMR 1051, Institut des Neurosciences de Montpellier, 80 rue Augustin Fliche, 34295, Montpellier, France
- Université Montpellier, 34295, Montpellier, France
| | - Florence François
- INSERM - UMR 1051, Institut des Neurosciences de Montpellier, 80 rue Augustin Fliche, 34295, Montpellier, France
- Université Montpellier, 34295, Montpellier, France
| | - Corentin Affortit
- INSERM - UMR 1051, Institut des Neurosciences de Montpellier, 80 rue Augustin Fliche, 34295, Montpellier, France
- Université Montpellier, 34295, Montpellier, France
| | - François Casas
- INRA, UMR 866 Différenciation Cellulaire et Croissance, 34060, Montpellier, France
| | - Jean-Charles Ceccato
- INSERM - UMR 1051, Institut des Neurosciences de Montpellier, 80 rue Augustin Fliche, 34295, Montpellier, France
- Université Montpellier, 34295, Montpellier, France
| | - Julien Menardo
- INSERM - UMR 1051, Institut des Neurosciences de Montpellier, 80 rue Augustin Fliche, 34295, Montpellier, France
- Université Montpellier, 34295, Montpellier, France
| | - Frederic Venail
- INSERM - UMR 1051, Institut des Neurosciences de Montpellier, 80 rue Augustin Fliche, 34295, Montpellier, France
- Université Montpellier, 34295, Montpellier, France
| | | | - Jean-Luc Puel
- INSERM - UMR 1051, Institut des Neurosciences de Montpellier, 80 rue Augustin Fliche, 34295, Montpellier, France
- Université Montpellier, 34295, Montpellier, France
| | - Jing Wang
- INSERM - UMR 1051, Institut des Neurosciences de Montpellier, 80 rue Augustin Fliche, 34295, Montpellier, France.
- Université Montpellier, 34295, Montpellier, France.
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Chu SF, Zhang Z, Zhou X, He WB, Chen C, Luo P, Liu DD, Ai QD, Gong HF, Wang ZZ, Sun HS, Feng ZP, Chen NH. Ginsenoside Rg1 protects against ischemic/reperfusion-induced neuronal injury through miR-144/Nrf2/ARE pathway. Acta Pharmacol Sin 2019; 40:13-25. [PMID: 30262824 PMCID: PMC6318278 DOI: 10.1038/s41401-018-0154-z] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 06/18/2018] [Indexed: 01/12/2023] Open
Abstract
Ginsenoside Rg1 (Rg1), a saponin extracted from Panax ginseng, has been well documented to be effective against ischemic/reperfusion (I/R) neuronal injury. However, the underlying mechanisms remain obscure. In the present study, we investigated the roles of Nrf2 and miR-144 in the protective effects of Rg1 against I/R-induced neuronal injury. In OGD/R-treated PC12 cells, Rg1 (0.01-1 μmol/L) dose-dependently attenuated the cell injury accompanied by prolonging nuclear accumulation of Nrf2, enhancing the transcriptional activity of Nrf2, as well as promoting the expression of ARE-target genes. The activation of the Nrf2/ARE pathway by Rg1 was independent of disassociation with Keap1, but resulted from post-translational regulations. Knockdown of Nrf2 abolished all the protective changes of Rg1 in OGD/R-treated PC12 cells. Furthermore, Rg1 treatment significantly decreased the expression of miR-144, which downregulated Nrf2 production by targeting its 3'-untranlated region after OGD/R. Knockdown of Nrf2 had no effect on the expression of miR-144, suggesting that miR-144 was an upstream regulator of Nrf2. We revealed that there was a direct binding between Nrf2 and miR-144 in PC12 cells. Application of anti-miR-144 occluded the activation of the Nrf2/ARE pathway by Rg1 in OGD/R-treated PC12 cells. In tMCAO rats, administration of Rg1 (20 mg/kg) significantly alleviated ischemic injury, and activated Nrf2/ARE pathway. The protective effects of Rg1 were abolished by injecting of AAV-HIF-miR-144-shRNA into the predicted ischemic penumbra. In conclusion, our results demonstrate that Rg1 alleviates oxidative stress after I/R through inhibiting miR-144 activity and subsequently promoting the Nrf2/ARE pathway at the post-translational level.
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Affiliation(s)
- Shi-Feng Chu
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China
| | - Zhao Zhang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China
| | - Xin Zhou
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China
| | - Wen-Bin He
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China
- Shanxi Key Laboratory of Chinese Medicine Encephalopathy, Shanxi University of Chinese Medicine, Jinzhong, 030619, China
| | - Chen Chen
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China
| | - Piao Luo
- Hunan University of Chinese Medicine, Changsha, 410208, China
| | - Dan-Dan Liu
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China
| | - Qi-di Ai
- Hunan University of Chinese Medicine, Changsha, 410208, China
| | - Hai-Fan Gong
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Zhen-Zhen Wang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China
| | - Hong-Shuo Sun
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Zhong-Ping Feng
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Nai-Hong Chen
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China.
- Hunan University of Chinese Medicine, Changsha, 410208, China.
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23
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Ji W, Wang L, He S, Yan L, Li T, Wang J, Kong ANT, Yu S, Zhang Y. Effects of acute hypoxia exposure with different durations on activation of Nrf2-ARE pathway in mouse skeletal muscle. PLoS One 2018; 13:e0208474. [PMID: 30513114 PMCID: PMC6279028 DOI: 10.1371/journal.pone.0208474] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 11/16/2018] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Hypoxia training enhances the endurance capacity of athletes. This response may in part be attributed to the hypoxia-induced increase in antioxidant capacity in skeletal muscles. Nuclear factor erythroid 2-related factor 2 (Nrf2), a key transcription factor which regulates the expression of genes via binding to the antioxidant-response element (ARE) of these genes, plays a crucial role in stimulating the body's defense system and potentially responds to hypoxia. Meanwhile, hypoxia-inducible factor-1α (HIF-1α) is an important player in protecting cells from hypoxic stress. The purpose of this study was to investigate the effects of acute hypoxia exposure with different durations on the activation of Nrf2-ARE pathway and a possible regulatory role of HIF-1α in these responses. METHODS C57BL/6J mice were allocated into the non-hypoxia 0-hour, 6-hour, 24-hour, and 48-hour hypoxic exposure (11.2% oxygen) groups. The quadriceps femoris was collected immediately after hypoxia. Further, to investigate the possible role of HIF-1α, C2C12 myoblasts with HIF-1α knockdown by small interfering RNA (siRNA) and the inducible HIF-1α transgenic mice were employed. RESULTS The results showed that 48-hour hypoxia exposure up-regulated protein expression of Nrf2, Nrf2/ARE binding activity and the transcription of antioxidative genes containing ARE (Sod1 and others) in mouse skeletal muscle. Moreover, HIF-1α siRNA group of C2C12 myoblasts showed a remarkable inhibition of Nrf2 protein expression and nuclear accumulation in hypoxia exposure for 72 hours compared with that in siRNA-Control group of the cells. In addition, HIF-1α transgenic mice gave higher Nrf2 protein expression, Nrf2/ARE binding activity and expressions of Nrf2-mediated antioxidative genes in their skeletal muscle, compared with those in the wild-type mice. CONCLUSIONS The findings suggested that the acute hypoxia exposure could trigger the activation of Nrf2-ARE pathway, with longer duration associated with higher responses, and HIF-1α expression might be involved in promoting the Nrf2-mediated antioxidant responses in skeletal muscle.
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Affiliation(s)
- Weixiu Ji
- School of Sport Science, Beijing Sport University, Beijing, China
- Tianjin University of Sport, Tianjin, China
| | - Linjia Wang
- School of Sport Science, Beijing Sport University, Beijing, China
| | - Shiyi He
- School of Sport Science, Beijing Sport University, Beijing, China
| | - Lu Yan
- School of Sport Science, Beijing Sport University, Beijing, China
| | - Tieying Li
- School of Sport Science, Beijing Sport University, Beijing, China
| | - Jianxiong Wang
- Faculty of Health, Engineering, and Sciences, University of Southern Queensland, Toowoomba, Queensland, Australia
| | - Ah-Ng Tony Kong
- Ernest Mario School of Pharmacy, Rutgers, the State University of New Jersey, Camden, New Jersey, United States of America
| | - Siwang Yu
- Department of Chemical Biology, School of Pharmaceutical Sciences, Peking University, Beijing, China
| | - Ying Zhang
- School of Sport Science, Beijing Sport University, Beijing, China
- * E-mail:
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24
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Zhu W, Ding Y, Kong W, Li T, Chen H. Docosahexaenoic Acid (DHA) Provides Neuroprotection in Traumatic Brain Injury Models via Activating Nrf2-ARE Signaling. Inflammation 2018; 41:1182-1193. [PMID: 29663102 DOI: 10.1007/s10753-018-0765-z] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In this study, we explored the neuroprotective effects of docosahexaenoic acid (DHA) in traumatic brain injury (TBI) models. In this study, we first confirmed that DHA was neuroprotective against TBI via the NSS test and Morris water maze experiment. Western blot was conducted to identify the expression of Bax, caspase-3, and Bcl-2. And the cell apoptosis of the TBI models was validated by TUNEL staining. Relationships between nuclear factor erythroid 2-related factor 2-antioxidant response element (Nrf2-ARE) pathway-related genes and DHA were explored by RT-PCR and Western blot. Rats of the DHA group performed remarkably better than those of the TBI group in both NSS test and water maze experiment. DHA conspicuously promoted the expression of Bcl-2 and diminished that of cleaved caspase-3 and Bax, indicating the anti-apoptotic role of DHA. Superoxide dismutase (SOD) activity and cortical malondialdehyde content, glutathione peroxidase (GPx) activity were renovated in rats receiving DHA treatment, implying that the neuroprotective influence of DHA was derived from lightening the oxidative stress caused by TBI. Moreover, immunofluorescence and Western blot experiments revealed that DHA facilitated the translocation of Nrf2 to the nucleus. DHA administration also notably increased the expression of the downstream factors NAD(P)H:quinone oxidoreductase (NQO-1) and heme oxygenase 1(HO-1). DHA exerted neuroprotective influence on the TBI models, potentially through activating the Nrf2- ARE pathway.
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Affiliation(s)
- Wei Zhu
- Department of Neurosurgery, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, No. 20 East Yuhuangding Road, Zhifu District, Yantai, 264000, Shandong, China.
| | - Yuexia Ding
- Department of Pharmacy, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, 264000, Shandong, China
| | - Wei Kong
- Department of Neurosurgery, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, No. 20 East Yuhuangding Road, Zhifu District, Yantai, 264000, Shandong, China
| | - Tuo Li
- Department of Neurosurgery, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, No. 20 East Yuhuangding Road, Zhifu District, Yantai, 264000, Shandong, China
| | - Hongguang Chen
- Department of Neurosurgery, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, No. 20 East Yuhuangding Road, Zhifu District, Yantai, 264000, Shandong, China
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25
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Lacher SE, Levings DC, Freeman S, Slattery M. Identification of a functional antioxidant response element at the HIF1A locus. Redox Biol 2018; 19:401-411. [PMID: 30241031 PMCID: PMC6146589 DOI: 10.1016/j.redox.2018.08.014] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 08/21/2018] [Accepted: 08/22/2018] [Indexed: 12/12/2022] Open
Abstract
Reactive oxygen species (ROS), which are a byproduct of oxidative metabolism, serve as signaling molecules in a number of physiological settings. However, if their levels are not tightly maintained, excess ROS lead to potentially cytotoxic oxidative stress. Accordingly, several transcriptional regulatory networks have evolved to include components that are highly ROS-responsive. Depending on the context, these regulatory networks can leverage ROS to respond to nutrient conditions, metabolism, or other physiological signals, or to respond to oxidative stress. However, ROS signaling is complex, so regulatory interactions between various ROS-responsive transcription factors are still being mapped out. Here we show that the transcription factor NRF2, a key regulator of the adaptive response to oxidative stress, directly regulates expression of HIF1A, which encodes HIF1α, a key transcriptional regulator of the adaptive response to hypoxia. We used an integrative genomics approach to identify HIF1A as a ROS-responsive transcript and we found an NRF2-bound antioxidant response element (ARE) approximately 30 kilobases upstream of HIF1A. This ARE sequence is deeply conserved, and we verified that it is directly bound and activated by NRF2. In addition, we found that HIF1A is upregulated in breast and bladder tumors with high NRF2 activity. Taken together, our results demonstrate that NRF2 targets a functional ARE at the HIF1A locus, and reveal a direct regulatory connection between two important oxygen responsive transcription factors.
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Affiliation(s)
- Sarah E Lacher
- Department of Biomedical Sciences, University of Minnesota Medical School, 1035 University Drive, SMed 255, Duluth, MN 55812, United States
| | - Daniel C Levings
- Department of Biomedical Sciences, University of Minnesota Medical School, 1035 University Drive, SMed 255, Duluth, MN 55812, United States
| | - Samuel Freeman
- Department of Biomedical Sciences, University of Minnesota Medical School, 1035 University Drive, SMed 255, Duluth, MN 55812, United States
| | - Matthew Slattery
- Department of Biomedical Sciences, University of Minnesota Medical School, 1035 University Drive, SMed 255, Duluth, MN 55812, United States.
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26
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Anderson RH, Lensing CJ, Forred BJ, Amolins MW, Aegerter CL, Vitiello PF, Mays JR. Differentiating Antiproliferative and Chemopreventive Modes of Activity for Electron-Deficient Aryl Isothiocyanates against Human MCF-7 Cells. ChemMedChem 2018; 13:1695-1710. [PMID: 29924910 PMCID: PMC6105534 DOI: 10.1002/cmdc.201800348] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 06/12/2018] [Indexed: 12/13/2022]
Abstract
The consumption of Brassica vegetables provides beneficial effects through organic isothiocyanates (ITCs), products of the enzymatic hydrolysis of glucosinolate secondary metabolites. The ITC l-sulforaphane (l-SFN) is the principle agent in broccoli that demonstrates several modes of anticancer action. While the anticancer properties of ITCs like l-SFN have been extensively studied and l-SFN has been the subject of multiple human clinical trials, the scope of this work has largely been limited to those derivatives found in nature. Previous studies have demonstrated that structural changes in an ITC can lead to marked differences in a compound's potency to 1) inhibit the growth of cancer cells, and 2) alter cellular transcriptional profiles. This study describes the preparation of a library of non-natural aryl ITCs and the development of a bifurcated screening approach to evaluate the dose- and time-dependence on antiproliferative and chemopreventive properties against human MCF-7 breast cancer cells. Antiproliferative effects were evaluated using a commercial MTS cell viability assay. Chemopreventive properties were evaluated using an antioxidant response element (ARE)-promoted luciferase reporter assay. The results of this study have led to the identification of 1) several key structure-activity relationships and 2) lead ITCs for continued development.
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Affiliation(s)
- Ruthellen H. Anderson
- Department of Chemistry Augustana University 2001 S. Summit Ave. Sioux Falls, SD 57197
| | - Cody J. Lensing
- Department of Chemistry Augustana University 2001 S. Summit Ave. Sioux Falls, SD 57197
| | - Benjamin J. Forred
- Environmental Influences on Health and Disease Group Sanford Research 2301 E. 60 St. N. Sioux Falls, SD 57104
| | - Michael W. Amolins
- Department of Chemistry Augustana University 2001 S. Summit Ave. Sioux Falls, SD 57197
- Environmental Influences on Health and Disease Group Sanford Research 2301 E. 60 St. N. Sioux Falls, SD 57104
| | - Cassandra L. Aegerter
- Environmental Influences on Health and Disease Group Sanford Research 2301 E. 60 St. N. Sioux Falls, SD 57104
| | - Peter F. Vitiello
- Environmental Influences on Health and Disease Group Sanford Research 2301 E. 60 St. N. Sioux Falls, SD 57104
| | - Jared R. Mays
- Department of Chemistry Augustana University 2001 S. Summit Ave. Sioux Falls, SD 57197
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27
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Tapias V, Jainuddin S, Ahuja M, Stack C, Elipenahli C, Vignisse J, Gerges M, Starkova N, Xu H, Starkov AA, Bettendorff L, Hushpulian DM, Smirnova NA, Gazaryan IG, Kaidery NA, Wakade S, Calingasan NY, Thomas B, Gibson GE, Dumont M, Beal MF. Benfotiamine treatment activates the Nrf2/ARE pathway and is neuroprotective in a transgenic mouse model of tauopathy. Hum Mol Genet 2018; 27:2874-2892. [PMID: 29860433 PMCID: PMC6077804 DOI: 10.1093/hmg/ddy201] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 04/26/2018] [Accepted: 05/01/2018] [Indexed: 12/21/2022] Open
Abstract
Impaired glucose metabolism, decreased levels of thiamine and its phosphate esters, and reduced activity of thiamine-dependent enzymes, such as pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase and transketolase occur in Alzheimer's disease (AD). Thiamine deficiency exacerbates amyloid beta (Aβ) deposition, tau hyperphosphorylation and oxidative stress. Benfotiamine (BFT) rescued cognitive deficits and reduced Aβ burden in amyloid precursor protein (APP)/PS1 mice. In this study, we examined whether BFT confers neuroprotection against tau phosphorylation and the generation of neurofibrillary tangles (NFTs) in the P301S mouse model of tauopathy. Chronic dietary treatment with BFT increased lifespan, improved behavior, reduced glycated tau, decreased NFTs and prevented death of motor neurons. BFT administration significantly ameliorated mitochondrial dysfunction and attenuated oxidative damage and inflammation. We found that BFT and its metabolites (but not thiamine) trigger the expression of Nrf2/antioxidant response element (ARE)-dependent genes in mouse brain as well as in wild-type but not Nrf2-deficient fibroblasts. Active metabolites were more potent in activating the Nrf2 target genes than the parent molecule BFT. Docking studies showed that BFT and its metabolites (but not thiamine) bind to Keap1 with high affinity. These findings demonstrate that BFT activates the Nrf2/ARE pathway and is a promising therapeutic agent for the treatment of diseases with tau pathology, such as AD, frontotemporal dementia and progressive supranuclear palsy.
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Affiliation(s)
- Victor Tapias
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Shari Jainuddin
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Manuj Ahuja
- Department of Pharmacology, Toxicology and Neurology, Augusta University, Augusta, GA 30912, USA
| | - Cliona Stack
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Ceyhan Elipenahli
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Julie Vignisse
- Laboratory of Neurophysiology, GIGA-Neurosciences, University of Liege, 4000 Liege, Belgium
| | - Meri Gerges
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Natalia Starkova
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Hui Xu
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Anatoly A Starkov
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Lucien Bettendorff
- Laboratory of Neurophysiology, GIGA-Neurosciences, University of Liege, 4000 Liege, Belgium
| | - Dmitry M Hushpulian
- D. Rogachev Federal Scientific and Clinical Center for Pediatric Hematology, Oncology, and Immunology, 117997 Moscow, Russia
- Veropharm, Abbott EPD, 115088 Moscow, Russia
| | - Natalya A Smirnova
- D. Rogachev Federal Scientific and Clinical Center for Pediatric Hematology, Oncology, and Immunology, 117997 Moscow, Russia
| | - Irina G Gazaryan
- Department of Chemistry and Physical Sciences, Pace University, Pleasantville, NY 10570, USA
- Department of Enzymology, School of Chemistry, 119991 Moscow, Russia
| | - Navneet A Kaidery
- Department of Pharmacology, Toxicology and Neurology, Augusta University, Augusta, GA 30912, USA
| | - Sushama Wakade
- Department of Pharmacology, Toxicology and Neurology, Augusta University, Augusta, GA 30912, USA
| | - Noel Y Calingasan
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Bobby Thomas
- Department of Pharmacology, Toxicology and Neurology, Augusta University, Augusta, GA 30912, USA
| | - Gary E Gibson
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
- Burke Medical Research Institute, Weill Cornell Medicine, White Plains, NY 10605, USA
| | - Magali Dumont
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - M Flint Beal
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
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Raghunath A, Sundarraj K, Nagarajan R, Arfuso F, Bian J, Kumar AP, Sethi G, Perumal E. Antioxidant response elements: Discovery, classes, regulation and potential applications. Redox Biol 2018; 17:297-314. [PMID: 29775961 PMCID: PMC6007815 DOI: 10.1016/j.redox.2018.05.002] [Citation(s) in RCA: 270] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 04/25/2018] [Accepted: 05/05/2018] [Indexed: 12/20/2022] Open
Abstract
Exposure to antioxidants and xenobiotics triggers the expression of a myriad of genes encoding antioxidant proteins, detoxifying enzymes, and xenobiotic transporters to offer protection against oxidative stress. This articulated universal mechanism is regulated through the cis-acting elements in an array of Nrf2 target genes called antioxidant response elements (AREs), which play a critical role in redox homeostasis. Though the Keap1/Nrf2/ARE system involves many players, AREs hold the key in transcriptional regulation of cytoprotective genes. ARE-mediated reporter constructs have been widely used, including xenobiotics profiling and Nrf2 activator screening. The complexity of AREs is brought by the presence of other regulatory elements within the AREs. The diversity in the ARE sequences not only bring regulatory selectivity of diverse transcription factors, but also confer functional complexity in the Keap1/Nrf2/ARE pathway. The different transcription factors either homodimerize or heterodimerize to bind the AREs. Depending on the nature of partners, they may activate or suppress the transcription. Attention is required for deeper mechanistic understanding of ARE-mediated gene regulation. The computational methods of identification and analysis of AREs are still in their infancy. Investigations are required to know whether epigenetics mechanism plays a role in the regulation of genes mediated through AREs. The polymorphisms in the AREs leading to oxidative stress related diseases are warranted. A thorough understanding of AREs will pave the way for the development of therapeutic agents against cancer, neurodegenerative, cardiovascular, metabolic and other diseases with oxidative stress.
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Affiliation(s)
- Azhwar Raghunath
- Molecular Toxicology Laboratory, Department of Biotechnology, Bharathiar University, Coimbatore 641046, Tamilnadu, India
| | - Kiruthika Sundarraj
- Molecular Toxicology Laboratory, Department of Biotechnology, Bharathiar University, Coimbatore 641046, Tamilnadu, India
| | - Raju Nagarajan
- Department of Biotechnology, Indian Institute of Technology Madras, Chennai 600036, Tamilnadu, India
| | - Frank Arfuso
- Stem Cell and Cancer Biology Laboratory, School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Perth, WA 6009, Australia
| | - Jinsong Bian
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117600 Singapore, Singapore
| | - Alan P Kumar
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117600 Singapore, Singapore; Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore; Medical Science Cluster, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Curtin Medical School, Faculty of Health Sciences, Curtin University, Perth, WA, Australia.
| | - Gautam Sethi
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117600 Singapore, Singapore.
| | - Ekambaram Perumal
- Molecular Toxicology Laboratory, Department of Biotechnology, Bharathiar University, Coimbatore 641046, Tamilnadu, India.
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Wilding CS. Regulating resistance: CncC:Maf, antioxidant response elements and the overexpression of detoxification genes in insecticide resistance. Curr Opin Insect Sci 2018; 27:89-96. [PMID: 30025640 DOI: 10.1016/j.cois.2018.04.006] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 03/12/2018] [Accepted: 04/09/2018] [Indexed: 05/24/2023]
Abstract
Although genetic and genomic tools have greatly furthered our understanding of resistance-associated mutations in molecular target sites of insecticides, the genomic basis of transcriptional regulation of detoxification loci in insect pests and vectors remains relatively unexplored. Recent work using RNAi, reporter assays and comparative genomics are beginning to reveal the molecular architecture of this response, identifying critical transcription factors and their binding sites. Central to this is the insect ortholog of the mammalian transcription factor Nrf2, Cap 'n' Collar isoform-C (CncC) which as a heterodimer with Maf-S regulates the transcription of phase I, II and III detoxification loci in a range of insects, with CncC knockdown or upregulation directly affecting phenotypic resistance. CncC:Maf binds to specific antioxidant response element sequences upstream of detoxification genes to initiate transcription. Recent work is now identifying these binding sites for resistance-associated loci and, coupled with genome sequence data and reporter assays, enabling identification of polymorphisms in the CncC:Maf binding site which regulate the insecticide resistance phenotype.
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Affiliation(s)
- Craig S Wilding
- School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool L3 3AF, UK.
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Liu MM, Huang KM, Qian L, Chatterjee P, Zhang S, Li R, Zhou S, Wang Z, Luo Y, Huang Y. Effects of bioactive constituents in the Traditional Chinese Medicinal formula Si-Wu-Tang on Nrf2 signaling and neoplastic cellular transformation. Phytomedicine 2018; 40:1-9. [PMID: 29496161 DOI: 10.1016/j.phymed.2017.12.031] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 11/28/2017] [Accepted: 12/26/2017] [Indexed: 06/08/2023]
Abstract
BACKGROUND The nuclear factor erythroid 2-related factor 2 (Nrf2) is a potential molecular target for cancer chemoprevention. Si-Wu-Tang (SWT), a popular traditional Chinese medicine for women's health, was reported with a novel activity of cancer prevention. PURPOSE The present study was aimed to identify the bioactive constituents in SWT responsible for the Nrf2 activating and cancer preventive activity and explore the pharmacological mechanisms. METHODS Nine compounds detectable from various batches of SWT were ranked using in silico molecular docking based on their ability to interfere the forming of Nrf2-Keap1 complex. The predicted Nrf2 activating effect was validated using the antioxidant response element (ARE) luciferase reporter assay and quantitative RT-PCR analysis for select Nrf2 regulated genes Hmox1, Nqo1 and Slc7a11. The antimutagenic activity of the compounds were determined by the Ames test. The chemopreventive activity of these compounds were assessed on EGF-induced neoplastic transformation of JB6 P+ cells, an established non-cancerous murine epidermal model for studying tumor promotion and identifying cancer preventive agents. These compounds were further characterized using luciferase reporter assay on EGF-induced activation of AP-1, a known transcription factor mediating carcinogenesis. RESULTS Three of the nine compounds predicted as Nrf2 activators by molecular docking, gallic acid (GA), Z-liguistilide (LIG), and senkyunolide A (SA), were confirmed with highest potency of increasing the Nrf2/ARE promoter activity and upregulating the expression of Hmox1, Nqo1 and Slc7a11. In addition, GA, LIG and SA exhibited an antimutagenic activity against the direct mutagen 2-nitrofluorene while no mutagenic effects were observed at the same time in Ames test. At nontoxic concentrations, GA, LIG, and SA inhibited EGF-induced neoplastic transformation of JB6 P+ cells. Combined treatment of GA, LIG and SA, in the same ratio as detected in SWT, showed enhanced effect against JB6 transformation compared with that of the single compound alone. GA, LIG and SA, alone or in combination, suppressed EGF-induced activation of AP-1. CONCLUSION We identified three bioactive constituents in SWT responsible for the Nrf2 activating and cancer preventive activity. This study provides evidence supporting novel molecular basis of SWT in cancer prevention.
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Affiliation(s)
- Mandy M Liu
- Department of Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, United States
| | - Kevin M Huang
- Department of Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, United States
| | - Li Qian
- Department of Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, United States
| | - Payal Chatterjee
- Department of Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, United States
| | - Suhui Zhang
- Department of Pharmacology and Toxicology, Shanghai Institute for Food and Drug Control, Shanghai, China
| | - Rui Li
- Department of Pharmacology and Toxicology, Shanghai Institute for Food and Drug Control, Shanghai, China
| | - Su Zhou
- Department of Pharmacology and Toxicology, Shanghai Institute for Food and Drug Control, Shanghai, China
| | - Zhijun Wang
- Department of Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, United States; Department of Pharmaceutical Sciences, College of Pharmacy, Marshall B. Ketchum University, Fullerton, CA 92831, United States
| | - Yun Luo
- Department of Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, United States
| | - Ying Huang
- Department of Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, United States.
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Seo JY, Kim BR, Oh J, Kim JS. Soybean-Derived Phytoalexins Improve Cognitive Function through Activation of Nrf2/HO-1 Signaling Pathway. Int J Mol Sci 2018; 19:E268. [PMID: 29337893 PMCID: PMC5796214 DOI: 10.3390/ijms19010268] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 12/31/2017] [Accepted: 01/13/2018] [Indexed: 01/19/2023] Open
Abstract
As soy-derived glyceollins are known to induce antioxidant enzymes in various types of cells and tissues, we hypothesized that the compounds could protect neurons from damage due to reactive oxygen species (ROS). In order to examine the neuroprotective effect of glyceollins, primary cortical neurons collected from mice and mouse hippocampal HT22 cells were challenged with glutamate. Glyceollins attenuated glutamate-induced cytotoxicity in primary cortical neuron isolated from mice carrying wild-type nuclear factor (erythroid-derived 2)-like 2 (Nrf2), but the compounds were ineffective in those isolated from Nrf2 knockout mice, suggesting the involvement of the Nrf2 signaling pathway in glyceollin-mediated neuroprotection. Furthermore, the inhibition of heme oxygenase-1 (HO-1), a major downstream enzyme of Nrf2, abolished the suppressive effect of glyceollins against glutamate-induced ROS production and cytotoxicity, confirming that activation of HO-1 by glyceollins is responsible for the neuroprotection. To examine whether glyceollins also improve cognitive ability, mice pretreated with glyceollins were challenged with scopolamine and subjected to behavioral tests. Glyceollins attenuated scopolamine-induced cognitive impairment of mice, but failed to enhance memory in Nrf2 knockout mice, suggesting that the memory-enhancing effect is also mediated by the Nrf2 signaling pathway. Overall, glyceollins showed neuroprotection against glutamate-induced damage, and attenuated scopolamine-induced memory deficits in an Nrf2-dependent manner.
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Affiliation(s)
- Ji Yeon Seo
- School of Food Science and Biotechnology (BK21plus Program), Kyungpook National University, Daegu 41566, Korea.
| | - Bo Ram Kim
- School of Food Science and Biotechnology (BK21plus Program), Kyungpook National University, Daegu 41566, Korea.
| | - Jisun Oh
- School of Food Science and Biotechnology (BK21plus Program), Kyungpook National University, Daegu 41566, Korea.
| | - Jong-Sang Kim
- School of Food Science and Biotechnology (BK21plus Program), Kyungpook National University, Daegu 41566, Korea.
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Sheng XJ, Tu HJ, Chien WL, Kang KH, Lu DH, Liou HH, Lee MJ, Fu WM. Antagonism of proteasome inhibitor-induced heme oxygenase-1 expression by PINK1 mutation. PLoS One 2017; 12:e0183076. [PMID: 28806787 PMCID: PMC5555616 DOI: 10.1371/journal.pone.0183076] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 07/29/2017] [Indexed: 11/25/2022] Open
Abstract
PTEN-induced putative kinase 1 (PINK1) is an integral protein in the mitochondrial membrane and maintains mitochondrial fidelity. Pathogenic mutations in PINK1 have been identified as a cause of early-onset autosomal recessive familial Parkinson’s disease (PD). The ubiquitin proteasome pathway is associated with neurodegenerative diseases. In this study, we investigated whether mutations of PINK1 affects the cellular stress response following proteasome inhibition. Administration of MG132, a peptide aldehyde proteasome inhibitor, significantly increased the expression of heme oxygenase-1 (HO-1) in rat dopaminergic neurons in the substantia nigra and in the SH-SY5Y neuronal cell line. The induction of HO-1 expression by proteasome inhibition was reduced in PINK1 G309D mutant cells. MG132 increased the levels of HO-1 through the Akt, p38, and Nrf2 signaling pathways. Compared with the cells expressing WT-PINK1, the phosphorylation of Akt and p38 was lower in those cells expressing the PINK1 G309D mutant, which resulted in the inhibition of the nuclear translocation of Nrf2. Furthermore, MG132-induced neuronal death was enhanced by the PINK1 G309D mutation. In this study, we demonstrated that the G309D mutation impairs the neuroprotective function of PINK1 following proteasome inhibition, which may be related to the pathogenesis of PD.
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Affiliation(s)
- Xiang-Jun Sheng
- Pharmacological Institute, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Hunag-Ju Tu
- Pharmacological Institute, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Wei-Lin Chien
- Pharmacological Institute, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Kai-Hsiang Kang
- Pharmacological Institute, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Dai-Hua Lu
- Pharmacological Institute, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Horng-Huei Liou
- Pharmacological Institute, College of Medicine, National Taiwan University, Taipei, Taiwan
- Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan
| | - Ming-Jen Lee
- Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan
- * E-mail: (WF); (ML)
| | - Wen-Mei Fu
- Pharmacological Institute, College of Medicine, National Taiwan University, Taipei, Taiwan
- * E-mail: (WF); (ML)
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Zhou LL, Zhou C, Liang XW, Feng Z, Liu ZP, Wang HL, Zhou XP. Self-protection against triptolide-induced toxicity in human hepatic cells via Nrf2-ARE-NQO1 pathway. Chin J Integr Med 2017; 23:929-936. [PMID: 28523535 DOI: 10.1007/s11655-017-2546-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Indexed: 12/27/2022]
Abstract
OBJECTIVE To find the signaling pathway of triptolide (TP)-induced liver injury and to reveal whether NF-E2-related factor 2 (Nrf2) plays an important role in cellular self-protection. METHODS The L-02 and HepG2 cells were cultured and treated with various concentrations of TP. The cell viability was observed, and the cell medium was collected for detecting the aspartate aminotransferase (ALT), alanine aminotransferase (AST), lactate dehydrogenase (LDH), superoxide dismutase (SOD) and L-glutathione production (GSH) levels. Nrf2 and its downstream target NAD(P)H: quinine oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1) expression, the nuclear translocation of Nrf2, and the binding ability of Nrf2 and antioxidant response element (ARE) were also identified. Meanwhile, shRNA was used to silence Nrf2 in L-02 cells to find out whether Nrf2 plays a protective role. RESULTS The viability of the L-02 and HepG2 cells treated with TP decreased in a doseand time-dependent manner, and TP (20-80 μg/mL) markedly induced the release of ALT, AST and LDH (P<0.05 or P<0.01), reduced the levels of SOD and GSH (P<0.01), and increased the intracellular reactive oxygen species. Meanwhile, TP augmented the Nrf2 expression in L-02 and HepG2 cells (P<0.05 or P<0.01), induced Nrf2 nuclear translocation, increased the Nrf2 ARE binding activity, and increased HO-1 and NQO1 expressions. Nrf2 knockdown revealed a more severe toxic effect of TP (P<0.05 or P<0.01). CONCLUSIONS Human hepatic cells treated with TP induced oxidative stress, and led to cytotoxicity. Self-protection against TP-induced toxicity in human hepatic cells might be via Nrf2-ARE-NQO1 transcriptional pathway.
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Affiliation(s)
- Ling-Ling Zhou
- School of Pharmacy, The First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Cong Zhou
- School of Pharmacy, The First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, 210023, China
- Department of Pharmacy, Wuxi No.9 People's Hospital, Soochow University, Wuxi Hand Surgery Hospital, Wuxi, Jiangsu Province, 214062, China
| | - Xiao-Wen Liang
- Therapeutics Research Centre, School of Medicine, The University of Queensland, Princess Alexandra Hospital, 4102, Woolloongabba, QLD, Australia
| | - Zhe Feng
- School of Pharmacy, The First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Zhang-Pu Liu
- School of Pharmacy, The First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Hao-Lu Wang
- Therapeutics Research Centre, School of Medicine, The University of Queensland, Princess Alexandra Hospital, 4102, Woolloongabba, QLD, Australia
| | - Xue-Ping Zhou
- School of Pharmacy, The First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, 210023, China.
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Zhang J, Zhou X, Wu W, Wang J, Xie H, Wu Z. Regeneration of glutathione by α-lipoic acid via Nrf2/ARE signaling pathway alleviates cadmium-induced HepG2 cell toxicity. Environ Toxicol Pharmacol 2017; 51:30-37. [PMID: 28262510 DOI: 10.1016/j.etap.2017.02.022] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2016] [Revised: 02/22/2017] [Accepted: 02/26/2017] [Indexed: 06/06/2023]
Abstract
Alpha-lipoic acid (α-LA) is an important antioxidant that is capable of regenerating other antioxidants, such as glutathione (GSH). However, the underlying molecular mechanism by which α-LA regenerates GSH remains poorly understood. The current study aimed to investigate whether α-LA regenerates GSH by activation of Nrf2 to alleviate cadmium-induced cytotoxicity in HepG2 cells. In the present study, we found that cadmium induced cell death by depletion of GSH through inactivation of Nrf2. Addition of α-LA to cadmium-treated cells reactivated Nrf2 and regenerated GSH through elevating the Nrf2-downstream genes γ-glutamate-cysteine ligase (γ-GCL) and GR, both of which are key enzymes for GSH synthesis. However, blocking Nrf2 with brusatol in the cells co-treated with α-LA and cadmium reduced the mRNA and the protein levels of γ-GCL and GR, thus suppressed GSH regeneration by α-LA. Our results indicated that α-LA activated Nrf2 signaling pathway, which upregulated the transcription of the enzymes for GSH synthesis and therefore GSH contents to alleviate cadmium-induced cytotoxicity in HepG2 cells.
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Affiliation(s)
- Jiayu Zhang
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, PR China; Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, PR China
| | - Xue Zhou
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, PR China; Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, PR China
| | - Wenbo Wu
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, PR China; Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, PR China
| | - Jiachun Wang
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, PR China; Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, PR China
| | - Hong Xie
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, PR China; Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, PR China
| | - Zhigang Wu
- Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, PR China; Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, PR China.
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Rajgopal A, Missler SR, Scholten JD. Magnolia officinalis (Hou Po) bark extract stimulates the Nrf2-pathway in hepatocytes and protects against oxidative stress. J Ethnopharmacol 2016; 193:657-662. [PMID: 27721050 DOI: 10.1016/j.jep.2016.10.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 09/14/2016] [Accepted: 10/05/2016] [Indexed: 06/06/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The highly aromatic bark of Magnolia officinalis Rehder and EH Wilson, (magnolia bark) has been widely used in traditional Chinese medicine where it is known as Hou Po. Historically the bark of the tree has been used for treating variety of disorders the most common use of magnolia bark in traditional prescription has been to treat stress and anxiety disorders. Till date it is not clear regarding the fundamental cellular pathway it modulates. NRF2 signaling has emerged as the central pathway that protects cells from variety of stressors this led us to hypothesize that basis for magnolia bark's effects could be via activating NRF2 pathway. MATERIALS AND METHODS We utilized variety of biochemical procedures like luciferase reporter assay, enzyme induction, gene expression to determine NRF2 inducing activity by magnolia bark extract and its significance. Further we identified the phytochemicals inducing this activity using bio-directed fractionation procedure. RESULTS In this study, we demonstrate that magnolia bark extract activates Nrf2-dependent gene expression and protects against hydrogen peroxide mediated oxidative stress in hepatocytes. We further identified through HPLC fractionation and mass spectroscopy that magnolol, 4-methoxy honokiol and honokiol are the active phytochemicals inducing the Nrf2-mediated activity. This could be the molecular basis for its numerous beneficial activity.
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Affiliation(s)
- Arun Rajgopal
- Analytical Sciences, Amway Corporation, 7575 East Fulton Avenue, Ada, MI 49355, United States.
| | - Stephen R Missler
- Analytical Sciences, Amway Corporation, 7575 East Fulton Avenue, Ada, MI 49355, United States
| | - Jeffery D Scholten
- Analytical Sciences, Amway Corporation, 7575 East Fulton Avenue, Ada, MI 49355, United States
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Abstract
BACKGROUND Combinations of adjuvant sensitizers with anticancer drugs is a promising new strategy to reverse chemoresistance. Ursolic acid (UA) is one of the natural pentacyclic triterpene compounds known to have many pharmacological characteristics such as anti-inflammatory and anticancer properties. This study investigates whether UA can sensitize hepatocellular carcinoma cells to cisplatin. MATERIALS AND METHODS Cells were transfected with nuclear factor erythroid-2-related factor 2 (Nrf2) small interfering RNA and Nrf2 complementary DNA by using Lipofectin 2000. The cytotoxicity of cells was investigated by Cell Counting Kit 8 assay. Cell apoptosis, cell cycle, reactive oxygen species, and mitochondrial membrane potential were detected by flow cytometry fluorescence-activated cell sorting. The protein level of Nrf2, NAD(P)H quinone oxidoreductase 1 (NQO1), glutathione S-transferase (GST), and heme oxygenase-1 (HO-1) was detected by Western blot analysis. RESULTS The results showed that the reverse index was 2.9- and 9.69-fold by UA of 1.125 μg/mL and 2.25 μg/mL, respectively, for cisplatin to HepG2/DDP cells. UA-cisplatin combination induced cell apoptosis and reactive oxygen species, blocked the cell cycle in G0/G1 phase, and reduced the mitochondrial membrane potential. Mechanistically, UA-cisplatin dramatically decreased the expression of Nrf2 and its downstream genes. The sensibilization of UA-cisplatin combination was diminished in Nrf2 small interfering RNA-transfected HepG2/DDP cells, as well as in Nrf2 complementary DNA-transfected HepG2/DDP cells. CONCLUSION The results confirmed the sensibilization of UA on HepG2/DDP cells to cisplatin, which was possibly mediated via the Nrf2/antioxidant response element pathway.
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Affiliation(s)
- Shouhai Wu
- School of Life Sciences, Sun Yat-sen University
- Center for Regenerative and Translational Medicine
| | | | - Jingsheng Du
- Department of Pharmacy, The Second Affiliated Hospital, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People’s Republic of China
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Yang X, Yao W, Shi H, Liu H, Li Y, Gao Y, Liu R, Xu L. Paeoniflorin protects Schwann cells against high glucose induced oxidative injury by activating Nrf2/ARE pathway and inhibiting apoptosis. J Ethnopharmacol 2016; 185:361-369. [PMID: 26979341 DOI: 10.1016/j.jep.2016.03.031] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 01/17/2016] [Accepted: 03/11/2016] [Indexed: 06/05/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Paeoniflorin (PF) is the principal bioactive component of Paeonia lactiflora Pall., which an included in Tang Luo Ning recipe, a traditional Chinese herbal medicine based on Huangqi Guizhi Wuwu decoction. PF is also widely used in Traditional Chinese Medicine for the treatment of blood-arthralgia disease including diabetic peripheral neuropathy (DPN), but its underlying molecular mechanism of neuroprotective effects is not yet well understood. Diabetic hyperglycemia induced oxidative stress in Schwann cells, an important component of the peripheral nervous system, has been proposed as a unifying mechanism for DPN. The objective of this study is to determine the effects of PF on Schwann cells oxidative stress and apoptosis induced by high glucose. MATERIALS AND METHODS RSC96 cells, a Schwann cell line, were treated with high glucose (150mM) and PF (1, 10 and 100μM). Subsequently, MTT assay was performed. The level of apoptosis was examined by flow cytometry and the oxidative stress was reflected by reactive oxygen species (ROS), malondialdehyde (MDA), glutathione S-transferases (GST) and glutathione peroxidase (GPX) levels. The mRNA expressions of Nuclear factor-E2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) were detected by qRT-PCR. The levels of Kelch-like ECH-associating protein 1 (Keap1), Nrf2, HO-1, γ-glutamylcysteine synthetase (γGCS), B-cell CLL/lymphoma 2 (Bcl-2), Bax and Caspase 3 were detected by High content analysis and/or Western blot. RESULTS The role of PF markedly suppressed high glucose induced Schwann cells oxidative stress by decreasing ROS and MDA levels and increasing GST and GPX activity. Western blot analysis showed that PF induced nuclear translocation of Nrf2. High content analysis showed that PF promoted Nrf2 dissociation from Keap1 and upregulating the Nrf2/ antioxidant response element (ARE) pathway. Furthermore, PF reduced Schwann cells apoptosis by increasing Bcl-2 and inhibiting Bax and Caspase-3 expressions. CONCLUSIONS PF in the management of Schwann cells oxidative stress induced by high glucose may be associated with activation of Nrf2/ARE pathway and Bcl-2-related apoptotic pathway.
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Affiliation(s)
- Xinwei Yang
- School of Traditional Chinese Medicine, Capital Medical University, #10, Youanmenwai Xitoutiao, Fengtai District, Beijing 100069, China; Beijing Key Lab of TCM Collateral Disease Theory Research China
| | - Weijie Yao
- School of Traditional Chinese Medicine, Capital Medical University, #10, Youanmenwai Xitoutiao, Fengtai District, Beijing 100069, China; Beijing Key Lab of TCM Collateral Disease Theory Research China
| | - Haotian Shi
- School of Traditional Chinese Medicine, Capital Medical University, #10, Youanmenwai Xitoutiao, Fengtai District, Beijing 100069, China; Beijing Key Lab of TCM Collateral Disease Theory Research China
| | - Haolong Liu
- School of Traditional Chinese Medicine, Capital Medical University, #10, Youanmenwai Xitoutiao, Fengtai District, Beijing 100069, China; Beijing Key Lab of TCM Collateral Disease Theory Research China
| | - Yangfan Li
- School of Traditional Chinese Medicine, Capital Medical University, #10, Youanmenwai Xitoutiao, Fengtai District, Beijing 100069, China; Beijing Key Lab of TCM Collateral Disease Theory Research China
| | - Yanbin Gao
- School of Traditional Chinese Medicine, Capital Medical University, #10, Youanmenwai Xitoutiao, Fengtai District, Beijing 100069, China; Beijing Key Lab of TCM Collateral Disease Theory Research China
| | - Renhui Liu
- School of Traditional Chinese Medicine, Capital Medical University, #10, Youanmenwai Xitoutiao, Fengtai District, Beijing 100069, China; Beijing Key Lab of TCM Collateral Disease Theory Research China
| | - Liping Xu
- School of Traditional Chinese Medicine, Capital Medical University, #10, Youanmenwai Xitoutiao, Fengtai District, Beijing 100069, China.
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Furfaro AL, Piras S, Domenicotti C, Fenoglio D, De Luigi A, Salmona M, Moretta L, Marinari UM, Pronzato MA, Traverso N, Nitti M. Role of Nrf2, HO-1 and GSH in Neuroblastoma Cell Resistance to Bortezomib. PLoS One 2016; 11:e0152465. [PMID: 27023064 PMCID: PMC4811586 DOI: 10.1371/journal.pone.0152465] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 03/15/2016] [Indexed: 01/10/2023] Open
Abstract
The activation of Nrf2 has been demonstrated to play a crucial role in cancer cell resistance to different anticancer therapies. The inhibition of proteasome activity has been proposed as a chemosensitizing therapy but the activation of Nrf2 could reduce its efficacy. Using the highly chemoresistant neuroblastoma cells HTLA-230, here we show that the strong reduction in proteasome activity, obtained by using low concentration of bortezomib (BTZ, 2.5 nM), fails in reducing cell viability. BTZ treatment favours the binding of Nrf2 to the ARE sequences in the promoter regions of target genes such as heme oxygenase 1 (HO-1), the modulatory subunit of γ-glutamylcysteine ligase (GCLM) and the transporter for cysteine (x-CT), enabling their transcription. GSH level is also increased after BTZ treatment. The up-regulation of Nrf2 target genes is responsible for cell resistance since HO-1 silencing and GSH depletion synergistically decrease BTZ-treated cell viability. Moreover, cell exposure to all-trans-Retinoic acid (ATRA, 3 μM) reduces the binding of Nrf2 to the ARE sequences, decreases HO-1 induction and lowers GSH level increasing the efficacy of bortezomib. These data suggest the role of Nrf2, HO-1 and GSH as molecular targets to improve the efficacy of low doses of bortezomib in the treatment of malignant neuroblastoma.
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Affiliation(s)
- A. L. Furfaro
- Giannina Gaslini Institute, Via Gerolamo Gaslini 5, 16147, Genova, Italy
| | - S. Piras
- Department of Experimental Medicine, University of Genoa, Via L.B. Alberti 2, 16132, Genova, Italy
| | - C. Domenicotti
- Department of Experimental Medicine, University of Genoa, Via L.B. Alberti 2, 16132, Genova, Italy
| | - D. Fenoglio
- Center of Excellence for Biomedical Research, Department of Internal Medicine, University of Genoa, 16132, Genova, Italy
| | - A. De Luigi
- IRCCS-Istituto di Ricerche Farmacologiche “Mario Negri”, Via Giuseppe La Masa 19, 20156, Milano, Italy
| | - M. Salmona
- IRCCS-Istituto di Ricerche Farmacologiche “Mario Negri”, Via Giuseppe La Masa 19, 20156, Milano, Italy
| | - L. Moretta
- Bambino Gesù Children's Hospital, IRCCS, Piazza S. Onofrio 4, 00165, Roma, Italy
| | - U. M. Marinari
- Department of Experimental Medicine, University of Genoa, Via L.B. Alberti 2, 16132, Genova, Italy
| | - M. A. Pronzato
- Department of Experimental Medicine, University of Genoa, Via L.B. Alberti 2, 16132, Genova, Italy
| | - N. Traverso
- Department of Experimental Medicine, University of Genoa, Via L.B. Alberti 2, 16132, Genova, Italy
| | - M. Nitti
- Department of Experimental Medicine, University of Genoa, Via L.B. Alberti 2, 16132, Genova, Italy
- * E-mail:
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Gao M, Liu Y, Chen Y, Yin C, Chen JJ, Liu S. miR-214 protects erythroid cells against oxidative stress by targeting ATF4 and EZH2. Free Radic Biol Med 2016; 92:39-49. [PMID: 26791102 DOI: 10.1016/j.freeradbiomed.2016.01.005] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Revised: 12/23/2015] [Accepted: 01/09/2016] [Indexed: 12/30/2022]
Abstract
Nuclear factor (erythroid-derived 2) like 2 (Nrf2) is a key regulator in protecting cells against stress by targeting many anti-stress response genes. Recent evidence also reveals that Nrf2 functions partially by targeting mircroRNAs (miRNAs). However, the understanding of Nrf2-mediated cytoprotection through miRNA-dependent mechanisms is largely unknown. In the current study, we identified a direct Nrf2 targeting miRNA, miR-214, and demonstrated a protective role of miR-214 in erythroid cells against oxidative stresses generated by radiation, excess iron and arsenic (As) exposure. miR-214 expression was transcriptionally repressed by Nrf2 through a canonical antioxidant response element (ARE) within its promoter region, and this repression is ROS-dependence. The suppression of miR-214 by Nrf2 could antagonize oxidative stress-induced cell death in erythroid cells by two ways. First, miR-214 directly targeted ATF4, a crucial transcriptional factor involved in anti-stress responses, down regulation of miR-214 releases the repression of ATF4 translation and leads to increased ATF4 protein content. Second, miR-214 was able to prevent cell death by targeting EZH2, the catalytic core component of PRC2 complex that is responsible for tri-methylation reaction at lysine 27 (K27) of histone 3 (H3) (H3K27me3), by which As-induced miR-214 reduction resulted in an increased global H3K27me3 level and a compromised overexpression of a pro-apoptotic gene Bim. These two pathways downstream of miR-214 synergistically cooperated to antagonize erythroid cell death upon oxidative stress. Our combined data revealed a protective role of miR-214 signaling in erythroid cells against oxidative stress, and also shed new light on Nrf2-mediated cytoprotective machinery.
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Affiliation(s)
- Ming Gao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yun Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031, China
| | - Yue Chen
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Urology, The Second Hospital of Tianjin Medical University, Tianjin Institute of Urology, Tianjin 300211, China
| | - Chunyang Yin
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Jane-Jane Chen
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Sijin Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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Bayele HK, Balesaria S, Srai SKS. Phytoestrogens modulate hepcidin expression by Nrf2: Implications for dietary control of iron absorption. Free Radic Biol Med 2015; 89:1192-202. [PMID: 26546695 PMCID: PMC4698393 DOI: 10.1016/j.freeradbiomed.2015.11.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Revised: 10/27/2015] [Accepted: 11/02/2015] [Indexed: 12/30/2022]
Abstract
Hepcidin is a liver-derived antimicrobial peptide that regulates iron absorption and is also an integral part of the acute phase response. In a previous report, we found evidence that this peptide could also be induced by toxic heavy metals and xenobiotics, thus broadening its teleological role as a defensin. However it remained unclear how its sensing of disparate biotic and abiotic stressors might be integrated at the transcriptional level. We hypothesized that its function in cytoprotection may be regulated by NFE2-related factor 2 (Nrf2), the master transcriptional controller of cellular stress defenses. In this report, we show that hepcidin regulation is inextricably linked to the acute stress response through Nrf2 signaling. Nrf2 regulates hepcidin expression from a prototypical antioxidant response element in its promoter, and by synergizing with other basic leucine-zipper transcription factors. We also show that polyphenolic small molecules or phytoestrogens commonly found in fruits and vegetables including the red wine constituent resveratrol can induce hepcidin expression in vitro and post-prandially, with concomitant reductions in circulating iron levels and transferrin saturation by one such polyphenol quercetin. Furthermore, these molecules derepress hepcidin promoter activity when its transcription by Nrf2 is repressed by Keap1. Taken together, the data show that hepcidin is a prototypical antioxidant response or cytoprotective gene within the Nrf2 transcriptional circuitry. The ability of phytoestrogens to modulate hepcidin expression in vivo suggests a novel mechanism by which diet may impact iron homeostasis.
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Affiliation(s)
- Henry K Bayele
- Department of Structural and Molecular Biology, Division of Biosciences, University College London, Gower Street, London WC1E 6BT United Kingdom.
| | - Sara Balesaria
- Department of Structural and Molecular Biology, Division of Biosciences, University College London, Gower Street, London WC1E 6BT United Kingdom
| | - Surjit K S Srai
- Department of Structural and Molecular Biology, Division of Biosciences, University College London, Gower Street, London WC1E 6BT United Kingdom.
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41
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Lacher SE, Lee JS, Wang X, Campbell MR, Bell DA, Slattery M. Beyond antioxidant genes in the ancient Nrf2 regulatory network. Free Radic Biol Med 2015; 88:452-465. [PMID: 26163000 PMCID: PMC4837897 DOI: 10.1016/j.freeradbiomed.2015.06.044] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 06/10/2015] [Accepted: 06/30/2015] [Indexed: 01/01/2023]
Abstract
Nrf2, a basic leucine zipper transcription factor encoded by the gene NFE2L2, is a master regulator of the transcriptional response to oxidative stress. Nrf2 is structurally and functionally conserved from insects to humans, and it heterodimerizes with the small MAF transcription factors to bind a consensus DNA sequence (the antioxidant response element, or ARE) and regulate gene expression. We have used genome-wide chromatin immunoprecipitation and gene expression data to identify direct Nrf2 target genes in Drosophila and humans. These data have allowed us to construct the deeply conserved ancient Nrf2 regulatory network-target genes that are conserved from Drosophila to human. The ancient network consists of canonical antioxidant genes, as well as genes related to proteasomal pathways and metabolism and a number of less expected genes. We have also used enhancer reporter assays and electrophoretic mobility-shift assays to confirm Nrf2-mediated regulation of ARE activity at a number of these novel target genes. Interestingly, the ancient network also highlights a prominent negative feedback loop; this, combined with the finding that Nrf2-mediated regulatory output is tightly linked to the quality of the ARE it is targeting, suggests that precise regulation of nuclear Nrf2 concentration is necessary to achieve proper quantitative regulation of distinct gene sets. Together, these findings highlight the importance of balance in the Nrf2-ARE pathway and indicate that Nrf2-mediated regulation of xenobiotic metabolism, glucose metabolism, and proteostasis has been central to this pathway since its inception.
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Affiliation(s)
- Sarah E Lacher
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812, USA
| | - Joslynn S Lee
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812, USA
| | - Xuting Wang
- Environmental Genomics Section, Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Michelle R Campbell
- Environmental Genomics Section, Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Douglas A Bell
- Environmental Genomics Section, Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Matthew Slattery
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812, USA; Developmental Biology Center, University of Minnesota, Minneapolis, MN 55455, USA.
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42
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Santofimia-Castaño P, Clea Ruy D, Garcia-Sanchez L, Jimenez-Blasco D, Fernandez-Bermejo M, Bolaños JP, Salido GM, Gonzalez A. Melatonin induces the expression of Nrf2-regulated antioxidant enzymes via PKC and Ca2+ influx activation in mouse pancreatic acinar cells. Free Radic Biol Med 2015; 87:226-36. [PMID: 26163001 DOI: 10.1016/j.freeradbiomed.2015.06.033] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Revised: 05/24/2015] [Accepted: 06/23/2015] [Indexed: 12/12/2022]
Abstract
The goal of this study was to evaluate the potential activation of the nuclear factor erythroid 2-related factor and the antioxidant-responsive element (Nrf2-ARE) signaling pathway in response to melatonin in isolated mouse pancreatic acinar cells. Changes in intracellular free Ca(2+) concentration were followed by fluorimetric analysis of fura-2-loaded cells. The activations of PKC and JNK were measured by Western blot analysis. Quantitative reverse transcription-polymerase chain reaction was employed to detect the expression of Nrf2-regulated antioxidant enzymes. Immunocytochemistry was employed to determine nuclear location of phosphorylated Nrf2, and the cellular redox state was monitored following MitoSOX Red-derived fluorescence. Our results show that stimulation of fura-2-loaded cells with melatonin (1 µM to 1 mM), in the presence of Ca(2+) in the extracellular medium, induced a slow and progressive increase of [Ca(2+)](c) toward a stable level. Melatonin did not inhibit the typical Ca(2+) response induced by CCK-8 (1 nM). When the cells were challenged with indoleamine in the absence of Ca(2+) in the extracellular solution (medium containing 0.5 mM EGTA) or in the presence of 1 mM LaCl(3), to inhibit Ca(2+) entry, we could not detect any change in [Ca(2+)](c). Nevertheless, CCK-8 (1 nM) was able to induce the typical mobilization of Ca(2+). When the cells were incubated with the PKC activator PMA (1 µM) in the presence of Ca(2+) in the extracellular medium, we observed a response similar to that noted when the cells were challenged with melatonin 100 µM. However, in the presence of Ro31-8220 (3 µM), a PKC inhibitor, stimulation of cells with melatonin failed to evoke changes in [Ca(2+)]c. Immunoblots, using an antibody specific for phospho-PKC, revealed that melatonin induces PKCα activation, either in the presence or in the absence of external Ca(2+). Melatonin induced the phosphorylation and nuclear translocation of the transcription factor Nrf2, and evoked a concentration-dependent increase in the expression of the antioxidant enzymes NAD(P)H-quinone oxidoreductase 1, catalytic subunit of glutamate-cysteine ligase, and heme oxygenase-1. Incubation of MitoSOX Red-loaded pancreatic acinar cells in the presence of 1 nM CCK-8 induced a statistically significant increase in dye-derived fluorescence, reflecting an increase in oxidation, that was abolished by pretreatment of cells with melatonin (100 µM) or PMA (1 µM). On the contrary, pretreatment with Ro31-8220 (3 µM) blocked the effect of melatonin on CCK-8-induced increase in oxidation. Finally, phosphorylation of JNK in the presence of CCK-8 or melatonin was also observed. We conclude that melatonin, via modulation of PKC and Ca(2+) signaling, could potentially stimulate the Nrf2-mediated antioxidant response in mouse pancreatic acinar cells.
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Affiliation(s)
| | - Deborah Clea Ruy
- Facultade de Agronomia & Medicina Veterinaria, Universidade de Brasilia, 70900-100, Brasilia DF, Brazil
| | - Lourdes Garcia-Sanchez
- Cell Physiology Research Group (FICEL), Department of Physiology, University of Extremadura, Caceres, Spain
| | - Daniel Jimenez-Blasco
- Institute of Functional Biology and Genomics (IBFG), University of Salamanca-CSIC, Salamanca, Spain
| | - Miguel Fernandez-Bermejo
- Cell Physiology Research Group (FICEL), Department of Physiology, University of Extremadura, Caceres, Spain; Department of Gastroenterology, San Pedro de Alcantara Hospital, E-10003 Caceres, Spain
| | - Juan P Bolaños
- Institute of Functional Biology and Genomics (IBFG), University of Salamanca-CSIC, Salamanca, Spain
| | - Gines M Salido
- Cell Physiology Research Group (FICEL), Department of Physiology, University of Extremadura, Caceres, Spain
| | - Antonio Gonzalez
- Cell Physiology Research Group (FICEL), Department of Physiology, University of Extremadura, Caceres, Spain.
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Ray PD, Huang BW, Tsuji Y. Coordinated regulation of Nrf2 and histone H3 serine 10 phosphorylation in arsenite-activated transcription of the human heme oxygenase-1 gene. Biochim Biophys Acta 2015; 1849:1277-88. [PMID: 26291278 DOI: 10.1016/j.bbagrm.2015.08.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 07/22/2015] [Accepted: 08/13/2015] [Indexed: 02/06/2023]
Abstract
Expression of the antioxidant gene heme oxygenase-1 (HO-1) is primarily induced through NF-E2-related factor 2 (Nrf2)-mediated activation of the antioxidant response element (ARE). Gene transcription is coordinately regulated by transcription factor activity at enhancer elements and epigenetic alterations such as the posttranslational modification of histone proteins. However, the role of histone modifications in the Nrf2-ARE axis remains largely uncharacterized. The environmental contaminant arsenite is a potent inducer of both HO-1 expression and phosphorylation of histone H3 serine 10 (H3S10); therefore, we investigated the relationships between Nrf2 and H3S10 phosphorylation in arsenite-induced, ARE-dependent, transcriptional activation of the human HO-1 gene. Arsenite increased phosphorylation of H3S10 both globally and at the HO-1 promoter concomitantly with HO-1 transcription in human HaCaT keratinocytes. Conversely, arsenite-induced H3S10 phosphorylation and HO-1 expression were blocked by N-acetylcysteine (NAC), the c-Jun N-terminal kinase (JNK) inhibitor SP600125, and JNK knockdown (siJNK). Interestingly, ablation of arsenite-induced H3S10 phosphorylation by SP600125 or siJNK did not inhibit Nrf2 nuclear accumulation nor ARE binding, despite inhibiting HO-1 expression. In response to arsenite, binding of Nrf2 to the HO-1 ARE preceded phosphorylation of H3S10 at the HO-1 ARE. Furthermore, arsenite-mediated occupancy of phosphorylated H3S10 at the HO-1 ARE was decreased in Nrf2-deficient mouse embryonic fibroblasts. These results suggest the involvement of H3S10 phosphorylation in the Nrf2-ARE axis by proposing that Nrf2 may influence H3S10 phosphorylation at the HO-1 ARE and additional promoter regions. Our data highlights the complex interplay between Nrf2 and H3S10 phosphorylation in arsenite-activated HO-1 transcription.
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Affiliation(s)
- Paul D Ray
- Department of Biological Sciences, North Carolina State University, Campus Box 7633, Raleigh, NC 27695-7633, United States
| | - Bo-Wen Huang
- Department of Biological Sciences, North Carolina State University, Campus Box 7633, Raleigh, NC 27695-7633, United States
| | - Yoshiaki Tsuji
- Department of Biological Sciences, North Carolina State University, Campus Box 7633, Raleigh, NC 27695-7633, United States.
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Jiménez-Osorio AS, Picazo A, González-Reyes S, Barrera-Oviedo D, Rodríguez-Arellano ME, Pedraza-Chaverri J. Nrf2 and redox status in prediabetic and diabetic patients. Int J Mol Sci 2014; 15:20290-305. [PMID: 25383674 PMCID: PMC4264167 DOI: 10.3390/ijms151120290] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 11/01/2014] [Accepted: 11/03/2014] [Indexed: 02/02/2023] Open
Abstract
The redox status associated with nuclear factor erythroid 2-related factor-2 (Nrf2) was evaluated in prediabetic and diabetic subjects. Total antioxidant status (TAS) in plasma and erythrocytes, glutathione (GSH) and malondialdehyde (MDA) content and activity of antioxidant enzymes were measured as redox status markers in 259 controls, 111 prediabetics and 186 diabetic type 2 subjects. Nrf2 was measured in nuclear extract fractions from peripheral blood mononuclear cells (PBMC). Nrf2 levels were lower in prediabetic and diabetic patients. TAS, GSH and activity of glutamate cysteine ligase were lower in diabetic subjects. An increase of MDA and superoxide dismutase activity was found in diabetic subjects. These results suggest that low levels of Nrf2 are involved in the development of oxidative stress and redox status disbalance in diabetic patients.
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Affiliation(s)
- Angélica S Jiménez-Osorio
- Faculty of Chemistry, Department of Biology, National Autonomous University of Mexico (UNAM), University City 04510 DF, Mexico.
| | - Alejandra Picazo
- Faculty of Medicine, Department of Pharmacology, National Autonomous University of Mexico (UNAM), University City 04510 DF, Mexico.
| | - Susana González-Reyes
- Faculty of Chemistry, Department of Biology, National Autonomous University of Mexico (UNAM), University City 04510 DF, Mexico.
| | - Diana Barrera-Oviedo
- Faculty of Medicine, Department of Pharmacology, National Autonomous University of Mexico (UNAM), University City 04510 DF, Mexico.
| | - Martha E Rodríguez-Arellano
- Research Department, Hospital Regional "Lic. Adolfo López Mateos", ISSSTE, Av. Universidad 1321, Florida 01030 DF, Mexico.
| | - José Pedraza-Chaverri
- Faculty of Chemistry, Department of Biology, National Autonomous University of Mexico (UNAM), University City 04510 DF, Mexico.
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Abstract
The concept of the Exposome is a compilation of diseases and one's lifetime exposure to chemicals, whether the exposure comes from environmental, dietary, or occupational exposures; or endogenous chemicals that are formed from normal metabolism, inflammation, oxidative stress, lipid peroxidation, infections, and other natural metabolic processes such as alteration of the gut microbiome. In this review, we have focused on the endogenous exposome, the DNA damage that arises from the production of endogenous electrophilic molecules in our cells. It provides quantitative data on endogenous DNA damage and its relationship to mutagenesis, with emphasis on when exogenous chemical exposures that produce identical DNA adducts to those arising from normal metabolism cause significant increases in total identical DNA adducts. We have utilized stable isotope labeled chemical exposures of animals and cells, so that accurate relationships between endogenous and exogenous exposures can be determined. Advances in mass spectrometry have vastly increased both the sensitivity and accuracy of such studies. Furthermore, we have clear evidence of which sources of exposure drive low dose biology that results in mutations and disease. These data provide much needed information to impact quantitative risk assessments, in the hope of moving towards the use of science, rather than default assumptions.
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Affiliation(s)
- Jun Nakamura
- University of North Carolina, Chapel Hill, NC, United States
| | - Esra Mutlu
- University of North Carolina, Chapel Hill, NC, United States
| | - Vyom Sharma
- University of North Carolina, Chapel Hill, NC, United States
| | - Leonard Collins
- University of North Carolina, Chapel Hill, NC, United States
| | - Wanda Bodnar
- University of North Carolina, Chapel Hill, NC, United States
| | - Rui Yu
- University of North Carolina, Chapel Hill, NC, United States
| | - Yongquan Lai
- University of North Carolina, Chapel Hill, NC, United States
| | - Benjamin Moeller
- University of North Carolina, Chapel Hill, NC, United States; Lovelace Respiratory Research Institute, Albuquerque, NM, United States
| | - Kun Lu
- University of North Carolina, Chapel Hill, NC, United States
| | - James Swenberg
- University of North Carolina, Chapel Hill, NC, United States.
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Wang XJ, Li Y, Luo L, Wang H, Chi Z, Xin A, Li X, Wu J, Tang X. Oxaliplatin activates the Keap1/Nrf2 antioxidant system conferring protection against the cytotoxicity of anticancer drugs. Free Radic Biol Med 2014; 70:68-77. [PMID: 24556415 DOI: 10.1016/j.freeradbiomed.2014.02.010] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 01/30/2014] [Accepted: 02/09/2014] [Indexed: 12/21/2022]
Abstract
Oxaliplatin is an important drug in the treatment of advanced metastatic colorectal cancer. NF-E2 p45-related factor 2 (Nrf2) is a key transcription factor that controls genes encoding cytoprotective and detoxifying enzymes through antioxidant-response elements (AREs) in their regulatory regions. Here, we report that oxaliplatin is an activator of the Nrf2 signaling pathway, with upregulation of ARE-driven genes and glutathione elevation. An injection of oxaliplatin into mice enhanced the expression of glutathione transferases and antioxidant enzymes in the small and large intestines of wild-type (WT) mice but not Nrf2(-/-) mice, indicating that oxaliplatin activates Nrf2 in vivo. Oxaliplatin failed to increase Nrf2 accumulation in non-small-cell lung cancer A549 cells, which harbor a dysfunctional somatic mutation of KEAP1. However, forced expression of WT mKeap1 restored the ability of oxaliplatin to activate the transcription factor. Cys(151) in Keap1 was required for the response stimulated by oxaliplatin. In addition, dichloro(1,2-diaminocyclohexane) platinum, a metabolite of oxaliplatin, was found to have the same effect in activating the ARE-gene battery as its parent drug, whereas another metabolite, oxalate, was ineffective. Moreover, two other platinum derivatives, cisplatin and carboplatin, had no effect on the Keap1/Nrf2 system. Furthermore, activation of Nrf2 by oxaliplatin reduced the sensitivity of colon cancer cells to therapeutic drugs. Conversely, knockdown of Nrf2 by Nrf2 siRNA reduced oxaliplatin-induced chemoresistance. Our study showed that oxaliplatin exerts protection against the cytotoxicity of anticancer drugs via Nrf2, indicating an important role of Nrf2 in oxaliplatin-based chemotherapy.
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Affiliation(s)
- Xiu Jun Wang
- Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou 310058, People׳s Republic of China.
| | - Yinyan Li
- Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou 310058, People׳s Republic of China
| | - Lin Luo
- Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou 310058, People׳s Republic of China
| | - Hongyan Wang
- Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou 310058, People׳s Republic of China; Department of Biochemistry and Genetics,School of Medicine, Zhejiang University, Hangzhou 310058, People׳s Republic of China
| | - Zhexu Chi
- Department of Biochemistry and Genetics,School of Medicine, Zhejiang University, Hangzhou 310058, People׳s Republic of China
| | - Ai Xin
- Department of Biochemistry and Genetics,School of Medicine, Zhejiang University, Hangzhou 310058, People׳s Republic of China
| | - Xin Li
- Department of Biochemistry and Genetics,School of Medicine, Zhejiang University, Hangzhou 310058, People׳s Republic of China
| | - Jiaguo Wu
- Division of Gastroenterology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou 310058, People׳s Republic of China
| | - Xiuwen Tang
- Department of Biochemistry and Genetics,School of Medicine, Zhejiang University, Hangzhou 310058, People׳s Republic of China.
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Wyche TP, Standiford M, Hou Y, Braun D, Johnson DA, Johnson JA, Bugni TS. Activation of the nuclear factor E2-related factor 2 pathway by novel natural products halomadurones A-D and a synthetic analogue. Mar Drugs 2013; 11:5089-99. [PMID: 24351907 PMCID: PMC3877905 DOI: 10.3390/md11125089] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 11/13/2013] [Accepted: 12/03/2013] [Indexed: 02/06/2023] Open
Abstract
Two novel chlorinated pyrones, halomadurones A and B, and two novel brominated analogues, halomadurones C and D, were isolated from a marine Actinomadura sp. cultivated from the ascidian Ecteinascidia turbinata. Additionally, a non-halogenated analogue, 2-methyl-6-((E)-3-methyl-1,3-hexadiene)-γ-pyrone, was synthesized to understand the role of the halogens for activity. Halomadurones C and D demonstrated potent nuclear factor E2-related factor antioxidant response element (Nrf2-ARE) activation, which is an important therapeutic approach for treatment of neurodegenerative diseases.
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Affiliation(s)
| | | | | | | | | | | | - Tim S Bugni
- Pharmaceutical Sciences Division, University of Wisconsin-Madison, 777 Highland Avenue, Madison, WI 53705, USA.
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Ishikado A, Sono Y, Matsumoto M, Robida-Stubbs S, Okuno A, Goto M, King GL, Keith Blackwell T, Makino T. Willow bark extract increases antioxidant enzymes and reduces oxidative stress through activation of Nrf2 in vascular endothelial cells and Caenorhabditis elegans. Free Radic Biol Med 2013; 65:1506-1515. [PMID: 23277146 PMCID: PMC3800243 DOI: 10.1016/j.freeradbiomed.2012.12.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 12/02/2012] [Accepted: 12/09/2012] [Indexed: 12/30/2022]
Abstract
Willow bark extract (WBE) is listed in the European Pharmacopoeia and has been traditionally used for treating fever, pain, and inflammation. Recent studies have demonstrated its clinical usefulness. This study investigated the antioxidative effects of WBE in human umbilical vein endothelial cells (HUVECs) and Caenorhabditis elegans. WBE prevented oxidative-stress-induced cytotoxicity of HUVECs and death of C. elegans. WBE dose-dependently increased mRNA and protein expression levels of the nuclear factor erythroid 2-related factor 2 (Nrf2) target genes heme oxygenase-1, γ-glutamylcysteine ligase modifier and catalytic subunits, and p62 and intracellular glutathione (GSH) in HUVECs. In the nematode C. elegans, WBE increased the expression of the gcs-1::green fluorescent protein reporter, a well-characterized target of the Nrf2 ortholog SKN-1, in a manner that was SKN-1-dependent. WBE increased intranuclear expression and DNA binding of Nrf2 and the activity of an antioxidant response element (ARE) reporter plasmid in HUVECs. WBE-induced expression of Nrf2-regulated genes and increased GSH levels in HUVECs were reduced by Nrf2 and p38 small interfering (si) RNAs and by the p38-specific inhibitor SB203580. Nrf2 siRNA reduced the cytoprotective effect of WBE against oxidative stress in HUVECs. Salicin, a major anti-inflammatory ingredient of WBE, failed to activate ARE-luciferase activity, whereas a salicin-free WBE fraction showed intensive activity. WBE induced antioxidant enzymes and prevented oxidative stress through activation of Nrf2 independent of salicin, providing a new potential explanation for the clinical usefulness of WBE.
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Affiliation(s)
| | - Yoko Sono
- R&D Department, Sunstar Inc., Osaka 569-1195, Japan
| | | | - Stacey Robida-Stubbs
- Section on Islet Cell & Regenerative Biology, Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA
| | - Aya Okuno
- R&D Department, Sunstar Inc., Osaka 569-1195, Japan
| | - Masashi Goto
- R&D Department, Sunstar Inc., Osaka 569-1195, Japan
| | - George L King
- Section on Vascular Cell Biology, Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA
| | - T Keith Blackwell
- Section on Islet Cell & Regenerative Biology, Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA.
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49
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Zou W, Chen C, Zhong Y, An J, Zhang X, Yu Y, Yu Z, Fu J. PI3K/Akt pathway mediates Nrf2/ARE activation in human L02 hepatocytes exposed to low-concentration HBCDs. Environ Sci Technol 2013; 47:12434-12440. [PMID: 24094245 DOI: 10.1021/es401791s] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We investigated the effects of hexabromocyclododecanes (HBCDs) at environmentally relevant concentrations on human L02 hepatocytes and explored possible underlying molecular mechanism(s), focusing on functional interactions between the phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) and nuclear factor-erythroid 2-related factor 2/antioxidant response element (Nrf2/ARE) pathways. The results showed that low concentrations of HBCDs could stimulate cell proliferation in a "DNA-dependent protein kinase catalytic subunit" (DNA-PKcs)-dependent manner, increase protein levels and nuclear translocation of transcription factor Nrf2, and upregulate expression of its target gene heme oxygenase-1 (HO-1). Electrophoretic mobility-shift assays (EMSAs) showed that ARE was a prominent element for HO-1 induction after low-concentration HBCDs exposure. The relationship between PI3K/Akt pathway and Nrf2/HO-1 axis was demonstrated by the finding that pretreatment with PI3K inhibitors (wortmannin, LY294002) attenuated the upregulation of Nrf2 expression induced by HBCDs exposure. Furthermore, knock-down of DNA-PKcs through small interfering RNA blocked Nrf2/HO-1 axis activation in L02 cells exposed to low-concentration HBCDs. Moreover, DNA-PKcs and phosphorylated Akt at Ser(473) proved to be crucial in regulating the Nrf2-ARE pathway. Thus, the PI3K/Akt pathway is essential in regulating Nrf2-ARE pathway activation in L02 cells induced by low-concentration HBCDs.
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Affiliation(s)
- Wen Zou
- Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University , Shanghai 200444, P. R. China
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50
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Nagy P, Varga Á, Pircs K, Hegedűs K, Juhász G. Myc-driven overgrowth requires unfolded protein response-mediated induction of autophagy and antioxidant responses in Drosophila melanogaster. PLoS Genet 2013; 9:e1003664. [PMID: 23950728 PMCID: PMC3738540 DOI: 10.1371/journal.pgen.1003664] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Accepted: 06/10/2013] [Indexed: 12/21/2022] Open
Abstract
Autophagy, a lysosomal self-degradation and recycling pathway, plays dual roles in tumorigenesis. Autophagy deficiency predisposes to cancer, at least in part, through accumulation of the selective autophagy cargo p62, leading to activation of antioxidant responses and tumor formation. While cell growth and autophagy are inversely regulated in most cells, elevated levels of autophagy are observed in many established tumors, presumably mediating survival of cancer cells. Still, the relationship of autophagy and oncogenic signaling is poorly characterized. Here we show that the evolutionarily conserved transcription factor Myc (dm), a proto-oncogene involved in cell growth and proliferation, is also a physiological regulator of autophagy in Drosophila melanogaster. Loss of Myc activity in null mutants or in somatic clones of cells inhibits autophagy. Forced expression of Myc results in cell-autonomous increases in cell growth, autophagy induction, and p62 (Ref2P)-mediated activation of Nrf2 (cnc), a transcription factor promoting antioxidant responses. Mechanistically, Myc overexpression increases unfolded protein response (UPR), which leads to PERK-dependent autophagy induction and may be responsible for p62 accumulation. Genetic or pharmacological inhibition of UPR, autophagy or p62/Nrf2 signaling prevents Myc-induced overgrowth, while these pathways are dispensable for proper growth of control cells. In addition, we show that the autophagy and antioxidant pathways are required in parallel for excess cell growth driven by Myc. Deregulated expression of Myc drives tumor progression in most human cancers, and UPR and autophagy have been implicated in the survival of Myc-dependent cancer cells. Our data obtained in a complete animal show that UPR, autophagy and p62/Nrf2 signaling are required for Myc-dependent cell growth. These novel results give additional support for finding future approaches to specifically inhibit the growth of cancer cells addicted to oncogenic Myc. The evolutionarily conserved transcription factor Myc promotes protein synthesis, cell growth and cancer progression through incompletely understood mechanisms. In this work, we show that forced expression of Myc induces the accumulation of abnormal proteins leading to unfolded protein responses (UPR), presumably by overloading the protein synthetic capacity of cells in Drosophila. UPR then results in autophagy-mediated breakdown and recycling of cytoplasmic material, and at the same time, to activation of antioxidant responses in these cells. Blocking the UPR stress signaling, autophagy and antioxidant pathways genetically, or by feeding larvae an autophagy-inhibiting drug, prevents overgrowth of Myc-expressing cells, but these treatments do not affect the growth of control cells in the same tissues. These results, together with recent reports in mammalian cancer models, suggest that drugs targeting UPR, autophagy and antioxidant responses may specifically inhibit cancer cell proliferation driven by oncogenic Myc.
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Affiliation(s)
- Péter Nagy
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
| | - Ágnes Varga
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
| | - Karolina Pircs
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
| | - Krisztina Hegedűs
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
| | - Gábor Juhász
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
- * E-mail:
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