Faculty Opinions recommendation of Oxidative and electrophilic stress induces multidrug resistance-associated protein transporters via the nuclear factor-E2-related factor-2 transcriptional pathway.

Trilobatin is a natural plant-derived glycosylated flavonoid that has been shown to exhibit multiple beneficial pharmacologic activities including protection of heart against H/R-induced cardiomyocyte injury. However, the molecular mechanisms underlying protection from H/R-induced cardiomyocyte injury remain unknown. Using H9C2 cells as a model, we examined the effect of trilobatin on H/R-induced cellular injury, apoptosis, and generation of reactive oxygen species. The results showed that trilobatin protected H9C2 cells not only from cell death and apoptosis, but also counteracted H/R-induced changes in malondialdehyde, superoxide dismutase, glutathione, and glutathione peroxidase. The evaluation of the mechanism underlying the effect of trilobatin on protection from H/R-induced cellular injury suggested changes in the regulation of nuclear factor erythroid 2-related factor 2/heme oxygenase-1 pathway.

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Protective Effect of Swertiamarin on Myocardial Injury Through Activation of Nrf2/HO-1 Pathway in Heart Failure Model of Rats

Current Topics in Nutraceutical Research ◽

10.37290/ctnr2641-452x.18:260-265 ◽

2020 ◽

Vol 18 (3) ◽

pp. 260-265

Author(s):

Xu Lin ◽

Zheng Xiaojun ◽

Lv Heng ◽

Mo Yipeng ◽

Tong Hong

Keyword(s):

Oxidative Stress ◽

Heart Failure ◽

Ejection Fraction ◽

Protective Effect ◽

Infarct Size ◽

Rat Model ◽

Left Ventricular ◽

Related Factor ◽

Nuclear Factor ◽

Internal Dimension

The purpose of this study was to evaluate the protective effect of swertiamarin on heart failure. To this end, a rat model of heart failure was established via left coronary artery ligation. Infarct size of heart tissues was determined using triphenyl tetrazolium chloride staining. Echocardiography was performed to evaluate cardiac function by the determination of ejection fraction, left ventricular internal dimension in diastole and left ventricular internal dimension in systole. The effect of swertiamarin on oxidative stress was evaluated via enzyme-linked immunosorbent assay. The mechanism was evaluated using western blot. Administration of swertiamarin reduced the infarct size of heart tissues in rat models with heart failure. Moreover, swertiamarin treatment ameliorated the cardiac function, increased ejection fraction and fractional shortening, decreased left ventricular internal dimension in diastole and left ventricular internal dimension in systole. Swertiamarin improved oxidative stress with reduced malondialdehyde, while increased superoxide dismutase, glutathione, and GSH peroxidase. Furthermore, nuclear-factor erythroid 2-related factor 2, heme oxygenase and NAD(P)H dehydrogenase (quinone 1) were elevated by swertiamarin treatment in heart tissues of rat model with heart failure. Swertiamarin alleviated heart failure through suppression of oxidative stress response via nuclear-factor erythroid 2-related factor 2/heme oxygenase-1 pathway providing a novel therapeutic strategy for heart failure.

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Recent advances in understanding NRF2 as a druggable target: development of pro-electrophilic and non-covalent NRF2 activators to overcome systemic side effects of electrophilic drugs like dimethyl fumarate

F1000Research ◽

10.12688/f1000research.12111.1 ◽

2017 ◽

Vol 6 ◽

pp. 2138 ◽

Cited By ~ 24

Author(s):

Takumi Satoh ◽

Stuart Lipton

Keyword(s):

Side Effects ◽

Specific Interaction ◽

Dimethyl Fumarate ◽

Carnosic Acid ◽

European Medicines Agency ◽

Related Factor ◽

Inflammatory Phase ◽

First Case ◽

Systemic Side Effects ◽

Transcriptional Pathway

Dimethyl fumarate (DMF) is an electrophilic compound previously called BG-12 and marketed under the name Tecfidera®. It was approved in 2013 by the US Food and Drug Administration and the European Medicines Agency for the treatment of relapsing multiple sclerosis. One mechanism of action of DMF is stimulation of the nuclear factor erythroid 2-related factor 2 (NRF2) transcriptional pathway that induces anti-oxidant and anti-inflammatory phase II enzymes to prevent chronic neurodegeneration. However, electrophiles such as DMF also produce severe systemic side effects, in part due to non-specific S-alkylation of cysteine thiols and resulting depletion of glutathione. This mini-review presents the present status and future strategy for NRF2 activators designed to avoid these side effects. Two modes of chemical reaction leading to NRF2 activation are considered here. The first mode is S-alkylation (covalent reaction) of thiols in Kelch-like ECH-associated protein 1 (KEAP1), which interacts with NRF2. The second mechanism involves non-covalent pharmacological inhibition of protein-protein interactions, in particular domain-specific interaction between NRF2 and KEAP1 or other repressor proteins involved in this transcriptional pathway. There have been significant advances in drug development using both of these mechanisms that can potentially avoid the systemic side effects of electrophilic compounds. In the first case concerning covalent reaction with KEAP1, monomethyl fumarate and monoethyl fumarate appear to represent safer derivatives of DMF. In a second approach, pro-electrophilic drugs, such as carnosic acid from the herb Rosmarinus officinalis, can be used as a safe pro-drug of an electrophilic compound. Concerning non-covalent activation of NRF2, drugs are being developed that interfere with the direct interaction of KEAP1-NRF2 or inhibit BTB domain and CNC homolog 1 (BACH1), which is a transcriptional repressor of the promoter where NRF2 binds.

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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?

International Journal of Molecular Sciences ◽

10.3390/ijms22158223 ◽

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.

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Crosstalk between Long-Term Sublethal Oxidative Stress and Detrimental Inflammation as Potential Drivers for Age-Related Retinal Degeneration

Antioxidants ◽

10.3390/antiox10010025 ◽

2020 ◽

Vol 10 (1) ◽

pp. 25

Author(s):

Lara Macchioni ◽

Davide Chiasserini ◽

Letizia Mezzasoma ◽

Magdalena Davidescu ◽

Pier Luigi Orvietani ◽

...

Keyword(s):

Oxidative Stress ◽

Molecular Mechanisms ◽

Age Related Macular Degeneration ◽

Inflammasome Activation ◽

Related Factor ◽

Nuclear Factor ◽

Rpe Cells ◽

Age Related ◽

Oxidative Insult

Age-related retinal degenerations, including age-related macular degeneration (AMD), are caused by the loss of retinal pigmented epithelial (RPE) cells and photoreceptors. The pathogenesis of AMD, deeply linked to the aging process, also involves oxidative stress and inflammatory responses. However, the molecular mechanisms contributing to the shift from healthy aging to AMD are still poorly understood. Since RPE cells in the retina are chronically exposed to a pro-oxidant microenvironment throughout life, we simulated in vivo conditions by growing ARPE-19 cells in the presence of 10 μM H2O2 for several passages. This long-term oxidative insult induced senescence in ARPE-19 cells without affecting cell proliferation. Global proteomic analysis revealed a dysregulated expression in proteins involved in antioxidant response, mitochondrial homeostasis, and extracellular matrix organization. The analyses of mitochondrial functionality showed increased mitochondrial biogenesis and ATP generation and improved response to oxidative stress. The latter, however, was linked to nuclear factor-κB (NF-κB) rather than nuclear factor erythroid 2–related factor 2 (Nrf2) activation. NF-κB hyperactivation also resulted in increased pro-inflammatory cytokines expression and inflammasome activation. Moreover, in response to additional pro-inflammatory insults, senescent ARPE-19 cells underwent an exaggerated inflammatory reaction. Our results indicate senescence as an important link between chronic oxidative insult and detrimental chronic inflammation, with possible future repercussions for therapeutic interventions.

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