scholarly journals Accelerated Ovarian Failure Induced by 4-Vinyl Cyclohexene Diepoxide in Nrf2 Null Mice

2006 ◽  
Vol 26 (3) ◽  
pp. 940-954 ◽  
Author(s):  
Xiaoming Hu ◽  
Jenny R. Roberts ◽  
Patrick L. Apopa ◽  
Yuet Wai Kan ◽  
Qiang Ma
Keyword(s):  
Cultured Cells ◽  
Antioxidant Response ◽  
Ovarian Follicles ◽  
Ovarian Failure ◽  
Protein Stabilization ◽  
Premature Aging ◽  
26S Proteasome ◽  
Related Factor ◽  
Key Enzyme ◽  
Biochemical Analyses

ABSTRACT Genetic and biochemical analyses have uncovered an essential role for nuclear factor erythroid 2-related factor 2 (Nrf2) in regulating phase II xenobiotic metabolism and antioxidant response. Here we show that Nrf2 protects against the ovarian toxicity of 4-vinylcyclohexene diepoxide (VCD) in mice. Nrf2−/− female mice exposed to VCD exhibit an age-dependent decline in reproduction leading to secondary infertility accompanied by hypergonadotropic hypogonadism after 30 weeks of age. VCD is shown to selectively destroy small ovarian follicles, resulting in early depletion of functional follicles. Treatment with VCD induces apoptotic death in cultured cells and in ovarian follicles, suggesting apoptosis as a mechanism of follicle loss. Loss of Nrf2 function blocks the basal and inducible expression of microsomal epoxide hydrolase, a key enzyme in the detoxification of VCD, and increases the oxidative stress in cells that is further exacerbated by VCD. Foxo3a, a repressor in the early stages of follicle activation, displays reduced expression in Nrf2−/− ovaries, causing accelerated growth of follicles in the absence of exposure to exogenous chemicals. Furthermore, Foxo3a is degraded through the 26S proteasome pathway in untreated cells and is induced by VCD via both Nrf2-dependent transcription and protein stabilization. This study demonstrates that Nrf2 serves as an essential sensor and regulator of chemical homeostasis in ovarian cells, protecting the cells from toxic chemicals by controlling metabolic detoxification, reactive oxygen species defense, and Foxo3a expression. In addition, these findings raise the possibility that exposure to environmental or occupational ovotoxicants plays a role in the premature ovarian failure commonly associated with infertility and premature aging in women.

scholarly journals Ezetimibe Prevents Ischemia/Reperfusion-Induced Oxidative Stress and Up-Regulates Nrf2/ARE and UPR Signaling Pathways

Antioxidants ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 349 ◽  
Author(s):  
Denise Peserico ◽  
Chiara Stranieri ◽  
Ulisse Garbin ◽  
Chiara Mozzini C ◽  
Elisa Danese ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Gene Expression ◽  
Cultured Cells ◽  
Ischemia Reperfusion ◽  
Cholesterol Absorption ◽  
Antioxidant Response ◽  
Related Factor ◽  
Cellular Models ◽  
Compound C ◽  
Cholesterol Absorption Inhibitor

Background: While reperfusion is crucial for survival after an episode of ischemia, it also causes oxidative stress. Nuclear factor-E2-related factor 2 (Nrf2) and unfolded protein response (UPR) are protective against oxidative stress and endoplasmic reticulum (ER) stress. Ezetimibe, a cholesterol absorption inhibitor, has been shown to activate the AMP-activated protein kinase (AMPK)/Nrf2 pathway. In this study we evaluated whether Ezetimibe affects oxidative stress and Nrf2 and UPR gene expression in cellular models of ischemia-reperfusion (IR). Methods: Cultured cells were subjected to simulated IR with or without Ezetimibe. Results: IR significantly increased reactive oxygen species (ROS) production and the percentage of apoptotic cells without the up-regulation of Nrf2, of the related antioxidant response element (ARE) gene expression or of the pro-survival UPR activating transcription factor 6 (ATF6) gene, whereas it significantly increased the pro-apoptotic CCAAT-enhancer-binding protein homologous protein (CHOP). Ezetimibe significantly decreased the cellular ROS formation and apoptosis induced by IR. These effects were paralleled by the up-regulation of Nrf2/ARE and ATF6 gene expression and by a down-regulation of CHOP. We also found that Nrf2 activation was dependent on AMPK, since Compound C, a pan inhibitor of p-AMPK, blunted the activation of Nrf2. Conclusions: Ezetimibe counteracts IR-induced oxidative stress and induces Nrf2 and UPR pathway activation.

scholarly journals Nrf2 activation as a future target of therapy for chronic diseases

2014 ◽  
Vol 4 (12) ◽  
pp. 510 ◽  
Author(s):  
Rame Taha ◽  
Gilbert Blaise
Keyword(s):  
Oxidative Stress ◽  
Chronic Diseases ◽  
Therapeutic Potential ◽  
Antioxidant Response ◽  
Premature Aging ◽  
Therapeutic Effects ◽  
Related Factor ◽  
Nrf2 Activation ◽  
Inflammatory Drugs ◽  
Therapeutic Alternatives

Background: Chronic inflammation integrally related to oxidative stress has been increasingly recognized as a contributing factor in various chronic diseases such as neurodegenerative diseases, pulmonary diseases, metabolic syndrome, and cardiovascular diseases as well as premature aging. Thus, inhibiting this vicious circle has the potential to delay, prevent progression, and treat those diseases. However, adverse effects of current anti-inflammatory drugs and the failure of exogenous antioxidant encourage scientists to develop new therapeutic alternatives. The nuclear factor E2-related factor 2 (Nrf2) is the transcription factor that is responsible for the expression of antioxidant response element (ARE)-regulated genes and have been described as having many therapeutic effects. In this review, we have discussed the role of oxidative stress in various chronic diseases. Furthermore, we have also explored various novel ways to activate Nrf2 either directly or indirectly, which may have therapeutic potential in attenuating oxidative stress, inflammation and mitochondrial dysfunction that contributes to chronic diseases.Keywords: Oxidative stress, Mitochondria, Inflammation, Nrf2, Nutrition, Chronic diseases

scholarly journals Role of Nrf2 and Its Activators in Respiratory Diseases

2019 ◽  
Vol 2019 ◽  
pp. 1-17 ◽  
Author(s):  
Qinmei Liu ◽  
Yun Gao ◽  
Xinxin Ci
Keyword(s):  
Respiratory Diseases ◽  
Respiratory Infections ◽  
Redox Balance ◽  
Antioxidant Response ◽  
Experimental Models ◽  
26S Proteasome ◽  
Chronic Obstructive ◽  
Related Factor ◽  
Protective Effects ◽  
Obstructive Pulmonary Disease

Transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) is a major regulator of antioxidant response element- (ARE-) driven cytoprotective protein expression. The activation of Nrf2 signaling plays an essential role in preventing cells and tissues from injury induced by oxidative stress. Under the unstressed conditions, natural inhibitor of Nrf2, Kelch-like ECH-associated protein 1 (Keap1), traps Nrf2 in the cytoplasm and promotes the degradation of Nrf2 by the 26S proteasome. Nevertheless, stresses including highly oxidative microenvironments, impair the ability of Keap1 to target Nrf2 for ubiquitination and degradation, and induce newly synthesized Nrf2 to translocate to the nucleus to bind with ARE. Due to constant exposure to external environments, including diverse pollutants and other oxidants, the redox balance maintained by Nrf2 is fairly important to the airways. To date, researchers have discovered that Nrf2 deletion results in high susceptibility and severity of insults in various models of respiratory diseases, including bronchopulmonary dysplasia (BPD), respiratory infections, acute respiratory distress syndrome (ARDS), chronic obstructive pulmonary disease (COPD), asthma, idiopathic pulmonary fibrosis (IPF), and lung cancer. Conversely, Nrf2 activation confers protective effects on these lung disorders. In the present review, we summarize Nrf2 involvement in the pathogenesis of the above respiratory diseases that have been identified by experimental models and human studies and describe the protective effects of Nrf2 inducers on these diseases.

scholarly journals DCAF1-targeting microRNA-3175 activates Nrf2 signaling and inhibits dexamethasone-induced oxidative injury in human osteoblasts

2021 ◽  
Vol 12 (11) ◽  
Author(s):  
Jing Chen ◽  
Jin-qian Liang ◽  
Yun-Fang Zhen ◽  
Lei Chang ◽  
Zhen-tao Zhou ◽  
...  
Keyword(s):  
Oxidative Injury ◽  
Antioxidant Response ◽  
Protein Stabilization ◽  
Related Factor ◽  
Activity Increase ◽  
Human Osteoblasts ◽  
Argonaute 2 ◽  
Ubiquitin E3 Ligase ◽  
Rna Immunoprecipitation ◽  
Nrf2 Protein

AbstractActivation of nuclear-factor-E2-related factor 2 (Nrf2) signaling can protect human osteoblasts from dexamethasone-induced oxidative injury. DDB1 and CUL4 associated factor 1 (DCAF1) is a novel ubiquitin E3 ligase for Nrf2 protein degradation. We identified a novel DCAF1-targeting miRNA, miR-3175. RNA pull-down, Argonaute 2 RNA-immunoprecipitation, and RNA fluorescent in situ hybridization results confirmed a direct binding between miR-3175 and DCAF1 mRNA in primary human osteoblasts. DCAF1 3′-untranslated region luciferase activity and its expression were significantly decreased after miR-3175 overexpression but were augmented with miR-3175 inhibition in human osteoblasts and hFOB1.19 osteoblastic cells. miR-3175 overexpression activated Nrf2 signaling, causing Nrf2 protein stabilization, antioxidant response (ARE) activity increase, and transcription activation of Nrf2-dependent genes in human osteoblasts and hFOB1.19 cells. Furthermore, dexamethasone-induced oxidative injury and apoptosis were largely attenuated by miR-3175 overexpression in human osteoblasts and hFOB1.19 cells. Importantly, shRNA-induced silencing or CRISPR/Cas9-mediated Nrf2 knockout abolished miR-3175 overexpression-induced osteoblast cytoprotection against dexamethasone. Conversely, DFAC1 knockout, by the CRISPR/Cas9 method, activated the Nrf2 cascade and inhibited dexamethasone-induced cytotoxicity in hFOB1.19 cells. Importantly, miR-3175 expression was decreased in necrotic femoral head tissues of dexamethasone-taking patients, where DCAF1 mRNA was upregulated. Together, silencing DCAF1 by miR-3175 activated Nrf2 signaling to inhibit dexamethasone-induced oxidative injury and apoptosis in human osteoblasts.

scholarly journals Role of Nrf2 in the regulation of the Mrp2 (ABCC2) gene

2006 ◽  
Vol 395 (3) ◽  
pp. 599-609 ◽  
Author(s):  
Valeska Vollrath ◽  
Ana M. Wielandt ◽  
Mirentxu Iruretagoyena ◽  
Jose Chianale
Keyword(s):  
Gene Expression ◽  
Transcriptional Activation ◽  
Protein Complexes ◽  
Antioxidant Response ◽  
Proximal Region ◽  
Common Mechanism ◽  
Related Factor ◽  
Key Enzyme ◽  
Chloramphenicol Acetyltransferase Gene ◽  
Nrf2 Protein

The Nrf2 (nuclear factor-erythroid 2 p45-related factor 2) transcription factor regulates gene expression of the GCLC (glutamate–cysteine ligase catalytic subunit), which is a key enzyme in glutathione synthesis, and GSTs (glutathione S-transferases) via the ARE (antioxidant-response element). The Mrp2 (multidrug-resistance protein 2) pump mediates the excretion of GSH and GSSG excretion as well as endo- and xeno-biotics that are conjugated with GSH, glucuronate or sulphate. Considering that Mrp2 acts synergistically with these enzymes, we hypothesized that the regulation of Mrp2 gene expression is also dependent on Nrf2. Using BHA (butylated hydroxyanisole), which is a classical activator of the ARE–Nrf2 pathway, we observed an increase in the transcriptional activity of Mrp2, GCLC and Gsta1/Gsta2 genes in the mouse liver. A similar pattern of co-induction of Mrp2 and GCLC genes was also observed in mouse (Hepa 1-6) and human (HepG2) hepatoma cells treated with BHA, β-NF (β-naphthoflavone), 2,4,5-T (trichlorophenoxyacetic acid) or 2AAF (2-acetylaminofluorene), suggesting that these genes share common mechanism(s) of transcriptional activation in response to exposure to xenobiotics. To define the mechanism of Mrp2 gene induction, the 5′-flanking region of the mouse Mrp2 gene (2.0 kb) was isolated, and two ARE-like sequences were found: ARE-2 (−1391 to −1381) and ARE-1 (−95 to −85). Deletion analyses demonstrated that the proximal region (−185 to +99) contains the elements for the basal expression and xenobiotic-mediated induction of the Mrp2 gene. Gel-shift and supershift assays indicated that Nrf2–protein complexes bind ARE sequences of the Mrp2 promoter, preferentially to the ARE-1 sequence. Overexpression of Nrf2 increased ARE-1-mediated CAT (chloramphenicol acetyltransferase) gene activity, while overexpression of mutant Nrf2 protein repressed the activity. Thus Nrf2 appears to regulate Mrp2 gene expression via an ARE element located at the proximal region of its promoter in response to exposure to xenobiotics.

scholarly journals Human Skin Lightening Efficacy of Resveratrol and Its Analogs: From in Vitro Studies to Cosmetic Applications

Antioxidants ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 332 ◽  
Author(s):  
Yong Chool Boo
Keyword(s):  
Human Skin ◽  
Posttranslational Modifications ◽  
Skin Aging ◽  
Premature Aging ◽  
Sirtuin 1 ◽  
Related Factor ◽  
Key Enzyme ◽  
Skin Lightening

Antioxidants are deemed useful in controlling oxidative stress associated with extrinsic skin aging and pigmentation disorders. Resveratrol is a polyphenol compound found in many edible plants such as Vitis vinifera, and its inhibitory effects on the catalytic activity, gene expression, and posttranslational modifications of tyrosinase, a key enzyme in the melanin biosynthetic pathway, provide a mechanistic basis for its antimelanogenic effects seen in melanocytic cells, three-dimensionally reconstituted skin models, and in vivo animal models. As a potent antioxidant and a modulator of nuclear factor erythroid 2-related factor 2 (Nrf2), and sirtuin 1, resveratrol can also regulate multiple signaling pathways associated with inflammation and premature aging. Recent clinical studies have supported the efficacy of resveratrol and its analogs, such as resveratryl triacetate (RTA) and resveratryl triglycolate (RTG), in human skin lightening and antiaging. These findings suggest that resveratrol and its analogs are potentially useful as skin lightening and antiaging agents in cosmetics.

scholarly journals Delivery of Cinnamic Aldehyde Antioxidant Response Activating nanoParticles (ARAPas) for Vascular Applications

Antioxidants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 709
Author(s):  
Ana E. Cartaya ◽  
Halle Lutz ◽  
Sophie Maiocchi ◽  
Morgan Nalesnik ◽  
Edward M. Bahnson
Keyword(s):  
Ex Vivo ◽  
Antioxidant Response ◽  
Related Factor ◽  
Cinnamic Aldehyde ◽  
Vsmc Proliferation ◽  
Nrf2 Activation ◽  
Selective Delivery ◽  
And Migration ◽  
Inner Vessel ◽  
Macrophage Uptake

Selective delivery of nuclear factor erythroid 2-related factor 2 (Nrf2) activators to the injured vasculature at the time of vascular surgical intervention has the potential to attenuate oxidative stress and decrease vascular smooth muscle cell (VSMC) hyperproliferation and migration towards the inner vessel wall. To this end, we developed a nanoformulation of cinnamic aldehyde (CA), termed Antioxidant Response Activating nanoParticles (ARAPas), that can be readily loaded into macrophages ex vivo. The CA-ARAPas-macrophage system was used to study the effects of CA on VSMC in culture. CA was encapsulated into a pluronic micelle that was readily loaded into both murine and human macrophages. CA-ARAPas inhibits VSMC proliferation and migration, and activates Nrf2. Macrophage-mediated transfer of CA-ARAPas to VSMC is evident after 12 h, and Nrf2 activation is apparent after 24 h. This is the first report, to the best of our knowledge, of CA encapsulation in pluronic micelles for macrophage-mediated delivery studies. The results of this study highlight the feasibility of CA encapsulation and subsequent macrophage uptake for delivery of cargo into other pertinent cells, such as VSMC.

scholarly journals Modulation of Nrf2 and NF-κB Signaling Pathways by Naturally Occurring Compounds in Relation to Cancer Prevention and Therapy. Are Combinations Better Than Single Compounds?

2021 ◽  
Vol 22 (15) ◽  
pp. 8223
Author(s):  
Violetta Krajka-Kuźniak ◽  
Wanda Baer-Dubowska
Keyword(s):  
Cancer Prevention ◽  
Signaling Pathways ◽  
Current Knowledge ◽  
Cancer Chemoprevention ◽  
Antioxidant Response ◽  
Natural Food ◽  
Related Factor ◽  
Nuclear Factor ◽  
Edible Plant ◽  
Prevention And Therapy

Nrf2 (nuclear factor erythroid 2-related factor 2) and NF-κB (nuclear factor–kappa B) signaling pathways play a central role in suppressing or inducing inflammation and angiogenesis processes. Therefore, they are involved in many steps of carcinogenesis through cooperation with multiple signaling molecules and pathways. Targeting both transcription factors simultaneously may be considered an equally important strategy for cancer chemoprevention and therapy. Several hundreds of phytochemicals, mainly edible plant and vegetable components, were shown to activate Nrf2 and mediate antioxidant response. A similar number of phytochemicals was revealed to affect NF-κB. While activation of Nrf2 and inhibition of NF-κB may protect normal cells against cancer initiation and promotion, enhanced expression and activation in cancer cells may lead to resistance to conventional chemo- or radiotherapy. Most phytochemicals, through different mechanisms, activate Nrf2, but others, such as luteolin, can act as inhibitors of both Nrf2 and NF-κB. Despite many experimental data confirming the above mechanisms currently, limited evidence exists demonstrating such activity in humans. Combinations of phytochemicals resembling that in a natural food matrix but allowing higher concentrations may improve their modulating effect on Nrf2 and NF-κB and ultimately cancer prevention and therapy. This review presents the current knowledge on the effect of selected phytochemicals and their combinations on Nrf2 and NF-κB activities in the above context.

scholarly journals Bisphenol A Modulates Autophagy and Exacerbates Chronic Kidney Damage in Mice

2021 ◽  
Vol 22 (13) ◽  
pp. 7189
Author(s):  
Alberto Ruiz Priego ◽  
Emilio González Parra ◽  
Sebastián Mas ◽  
José Luis Morgado-Pascual ◽  
Marta Ruiz-Ortega ◽  
...  
Keyword(s):  
Bisphenol A ◽  
Hepatitis A Virus ◽  
Antioxidant Response ◽  
Heme Oxygenase 1 ◽  
Tubular Damage ◽  
Related Factor ◽  
Related Gene ◽  
Inflammatory Infiltration ◽  
Proximal Tubular Epithelial Cells

BACKGROUND: Bisphenol A (BPA) is a ubiquitous environmental toxin that accumulates in chronic kidney disease (CKD). Our aim was to explore the effect of chronic exposition of BPA in healthy and injured kidney investigating potential mechanisms involved. METHODS: In C57Bl/6 mice, administration of BPA (120 mg/kg/day, i.p for 5 days/week) was done for 2 and 5 weeks. To study BPA effect on CKD, a model of subtotal nephrectomy (SNX) combined with BPA administration for 5 weeks was employed. In vitro studies were done in human proximal tubular epithelial cells (HK-2 line). RESULTS: Chronic BPA administration to healthy mice induces inflammatory infiltration in the kidney, tubular injury and renal fibrosis (assessed by increased collagen deposition). Moreover, in SNX mice BPA exposure exacerbates renal lesions, including overexpression of the tubular damage biomarker Hepatitis A virus cellular receptor 1 (Havcr-1/KIM-1). BPA upregulated several proinflammatory genes and increased the antioxidant response [Nuclear factor erythroid 2-related factor 2 (Nrf2), Heme Oxygenase-1 (Ho-1) and NAD(P)H dehydrogenase quinone 1 (Nqo-1)] both in healthy and SNX mice. The autophagy process was modulated by BPA, through elevated autophagy-related gene 5 (Atg5), autophagy-related gene 7 (Atg7), Microtubule-associated proteins 1A/1B light chain 3B (Map1lc3b/Lc3b) and Beclin-1 gene levels and blockaded the autophagosome maturation and flux (p62 levels). This autophagy deregulation was confirmed in vitro. CONCLUSIONS: BPA deregulates autophagy flux and redox protective mechanisms, suggesting a potential mechanism of BPA deleterious effects in the kidney.

scholarly journals Marine Compound 3-bromo-4,5-dihydroxybenzaldehyde Protects Skin Cells against Oxidative Damage via the Nrf2/HO-1 Pathway

Marine Drugs ◽  
2019 ◽  
Vol 17 (4) ◽  
pp. 234 ◽  
Author(s):  
Yea Seong Ryu ◽  
Pincha Devage Sameera Madushan Fernando ◽  
Kyoung Ah Kang ◽  
Mei Jing Piao ◽  
Ao Xuan Zhen ◽  
...  
Keyword(s):  
Oxidative Damage ◽  
Antioxidant Response ◽  
Signaling Cascades ◽  
Heme Oxygenase 1 ◽  
Related Factor ◽  
Skin Cells ◽  
Reverse Transcription Pcr ◽  
Extracellular Signal ◽  
Diphenyltetrazolium Bromide ◽  
Marine Compound

In this study, we aimed to illustrate the potential bio-effects of 3-bromo-4,5-dihydroxybenzaldehyde (3-BDB) on the antioxidant/cytoprotective enzyme heme oxygenase-1 (HO-1) in keratinocytes. The antioxidant effects of 3-BDB were examined via reverse transcription PCR, Western blotting, HO-1 activity assay, and immunocytochemistry. Chromatin immunoprecipitation analysis was performed to test for nuclear factor erythroid 2-related factor 2 (Nrf2) binding to the antioxidant response element of the HO-1 promoter. Furthermore, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that the cytoprotective effects of 3-BDB were mediated by the activation of extracellular signal-regulated kinase (ERK) and protein kinase B (PKB, Akt) signaling. Moreover, 3-BDB induced the phosphorylation of ERK and Akt, while inhibitors of ERK and Akt abrogated the 3-BDB-enhanced levels of HO-1 and Nrf2. Finally, 3-BDB protected cells from H2O2- and UVB-induced oxidative damage. This 3-BDB-mediated cytoprotection was suppressed by inhibitors of HO-1, ERK, and Akt. The present results indicate that 3-BDB activated Nrf2 signaling cascades in keratinocytes, which was mediated by ERK and Akt, upregulated HO-1, and induced cytoprotective effects against oxidative stress.

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