A potent Nrf2 activator, dh404, bolsters antioxidant capacity in glial cells and attenuates ischaemic retinopathy

2016 ◽  
Vol 130 (15) ◽  
pp. 1375-1387 ◽  
Author(s):  
Devy Deliyanti ◽  
Jae Young Lee ◽  
Steven Petratos ◽  
Colin J. Meyer ◽  
Keith W. Ward ◽  
...  

A novel and potent nuclear factor erythroid-2 related factor 2 (Nrf2) activator, dh404, attenuates retinal vasculopathy by reducing oxidative stress-mediated damage to glia. Nrf2 agonists represent an effective strategy to improve vision-threatening glial and vascular cell pathology in ischaemic retinopathies.

2021 ◽  
Author(s):  
Shunxi Zhang ◽  
Jia He Zhao ◽  
Zhihuai Bai ◽  
Fan Wu ◽  
Lina Luo ◽  
...  

Sulforaphane (SFN), a potent nuclear factor erythroid 2-related factor 2 (Nrf2) activator, presents a very potential role in improving the Alzheimer's disease (AD)-specific symptoms. However, the regulation mechanism of SFN...


2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 116-116
Author(s):  
Mi-Bo Kim ◽  
Hyunju Kang ◽  
Ji-Young Lee

Abstract Objectives Anti-inflammatory and antioxidant effects of fucoxanthin (FCX), a carotenoid present in edible brown seaweeds, have been suggested. However, the underlying mechanisms have not been fully understood. The objectives of this study were to determine whether FCX can inhibit lipopolysaccharide (LPS)-induced inflammation and oxidative stress and to elucidate the underlying mechanisms in macrophages. Methods Cytotoxicity of FCX (0–15 μM) was measured in RAW 264.7 macrophage. The effects of the FCX on LPS-induced inflammatory cytokine and antioxidant gene expression were determined in RAW 264.7 macrophages by quantitative realtime PCR, Western blot, and enzyme-linked immunosorbent assays. Cellular reactive oxygen species (ROS) accumulation was measured in LPS-induced RAW 264.7 macrophage. The antioxidant capacity was also determined by 2,2′-azinobis (3-ethylbenzothiazoline 6-sulfonate) (ABTS) radical scavenging activity expressed by trolox equivalent antioxidant capacity (TEAC). Also, a potential role of phosphatidylinositol 3-kinase (PI3K)/nuclear factor E2-related factor 2 (NRF2) axis, a crucial pathway in endogenous antioxidant defense, in the FCX effects was evaluated. Results Cells treated with 5 μM FCX were 90%<viable. LPS significantly increased mRNA levels of interleukin (Il)-6, Il-1β, and tumor necrosis factor α (Tnf) as well as TNFα secretion, which were significantly decreased by FCX. Elevated levels of cellular ROS levels by LPS were abolished by FCX with a concomitant increase in the expression of antioxidant enzymes. ABTS assay demonstrated that FCX had a stronger free radical scavenging property (57.6 TEAC μM/100 μM). Also, FCX significantly increased Nrf2 and heme oxygenase 1 expression compared to LPS control. LPS increased the nuclear translocation of NRF2, which was further increased by FCX. Interestingly, LY294002, an inhibitor of PI3K, noticeably decreased the effect of FCX on NRF2 nuclear translocation. Conclusions FCX exerts anti-inflammatory and antioxidant effects by the activation of NRF2 in LPS-induced macrophages. The increase in NRF2 nuclear translocation is mediated, at least in part, through the PI3K pathway. Funding Sources This study was supported by National Research Foundation of Korea (2019R1A6A3A03032678).


2020 ◽  
Vol 18 (3) ◽  
pp. 260-265
Author(s):  
Xu Lin ◽  
Zheng Xiaojun ◽  
Lv Heng ◽  
Mo Yipeng ◽  
Tong Hong

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.


Antioxidants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 25
Author(s):  
Lara Macchioni ◽  
Davide Chiasserini ◽  
Letizia Mezzasoma ◽  
Magdalena Davidescu ◽  
Pier Luigi Orvietani ◽  
...  

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.


2021 ◽  
pp. 096032712110361
Author(s):  
Hai-Tao Zhang ◽  
Xi-Zeng Wang ◽  
Qing-Mei Zhang ◽  
Han Zhao

Objective To explore the mechanism of chromobox 7 (CBX7)-mediated nuclear factor E2-related factor 2 (Nrf2)/hemeoxygenase-1 (HO-1) signaling pathway in the cerebral ischemia/reperfusion (I/R) injury. Methods The experimental wild-type (WT) and CBX7-/- mice were used to establish cerebral I/R models using the middle cerebral artery occlusion (MCAO) surgery to determine CBX7 levels at different time points after MCAO injury. For all mice, neurological behavior, infarct size, water content, and oxidative stress–related indicators were determined, and transferase (TdT)-mediated dUTP-biotin nick-end labeling (terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL)) staining method was employed to observe cell apoptosis, while Western blot to measure the expression of CBX7 and Nrf/HO-1 pathway-related proteins. Results At 6 h, 12 h, 24 h, 3 days, and 7 days after mice with MCAO, CBX7 expression was gradually up-regulated and the peak level was reached at 24 h. Mice in the WT + MCAO group had increased infarct size, with significant increases in the modified neurological severity scores and water content in the brain, as well as the quantity of TUNEL-positive cells. For the oxidative stress-indicators, an increase was seen in the content of MDA (malondial dehyde), but the activity of SOD (superoxide dismutase) and content of GSH-PX (glutathione peroxidase) and CAT (catalase) were decreased; meanwhile, the protein expression of CBX7, HO-1, and nuclear Nrf2 was up-regulated, while the cytoplasmic Nrf2 was down-regulated. Moreover, CBX7 knockout attenuated I/R injury in mice. Conclusion Knockout of CBX7 may protect mice from cerebral I/R injury by reducing cell apoptosis and oxidative stress, possibly via activating the Nrf2/HO-1 pathway.


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3174
Author(s):  
Nhung Quynh Do ◽  
Shengdao Zheng ◽  
Bom Park ◽  
Quynh T. N. Nguyen ◽  
Bo-Ram Choi ◽  
...  

Myrciaria dubia (HBK) McVaugh (camu-camu) belongs to the family Myrtaceae. Although camu-camu has received a great deal of attention for its potential pharmacological activities, there is little information on the anti-oxidative stress and anti-inflammatory effects of camu-camu fruit in skin diseases. In the present study, we investigated the preventative effect of 70% ethanol camu-camu fruit extract against high glucose-induced human keratinocytes. High glucose-induced overproduction of reactive oxygen species (ROS) was inhibited by camu-camu fruit treatment. In response to ROS reduction, camu-camu fruit modulated the mitogen-activated protein kinases (MAPK)/activator protein-1 (AP-1), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and nuclear factor of activated T cells (NFAT) signaling pathways related to inflammation by downregulating the expression of proinflammatory cytokines and chemokines. Furthermore, camu-camu fruit treatment activated the expression of nuclear factor E2-related factor 2 (Nrf2) and subsequently increased the NAD(P)H:quinone oxidoreductase1 (NQO1) expression to protect keratinocytes against high-glucose-induced oxidative stress. These results indicate that camu-camu fruit is a promising material for preventing oxidative stress and skin inflammation induced by high glucose level.


Antioxidants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 856
Author(s):  
Eui-Jeong Han ◽  
Ilekuttige Priyan Shanura Fernando ◽  
Hyun-Soo Kim ◽  
Dae-Sung Lee ◽  
Areum Kim ◽  
...  

The present study evaluated the effects of (–)-loliolide isolated from Sargassum horneri (S. horneri) against oxidative stress and inflammation, and its biological mechanism in interferon (IFN)-γ/tumor necrosis factor (TNF)-α-stimulated HaCaT keratinocytes. The results showed that (–)-loliolide improved the cell viability by reducing the production of intracellular reactive oxygen species (ROS) in IFN-γ/TNF-α-stimulated HaCaT keratinocytes. In addition, (–)-loliolide effectively decreased the expression of inflammatory cytokines (interleukin (IL)-4 IL-6, IL-13, IFN-γ and TNF-α) and chemokines (CCL11 (Eotaxin), macrophage-derived chemokine (MDC), regulated on activation, normal T cell expressed and secreted (RANTES), and thymus and activation-regulated chemokine (TARC)), by downregulating the expression of epidermal-derived initial cytokines (IL-25, IL-33 and thymic stromal lymphopoietin (TSLP)). Furthermore, (–)-loliolide suppressed the activation of mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling, whereas it activated nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling. Interestingly, the cytoprotective effects of (–)-loliolide against IFN-γ/TNF-α stimulation were significantly blocked upon inhibition of HO-1. Taken together, these results suggest that (–)-loliolide effectively suppressed the oxidative stress and inflammation by activating the Nrf2/HO-1 signaling in IFN-γ/TNF-α-stimulated HaCaT keratinocytes.


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Yasuhiro Nakagami

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a redox-sensitive transcription factor that binds to antioxidant response elements located in the promoter region of genes encoding many antioxidant enzymes and phase II detoxifying enzymes. Activation of Nrf2 functions is one of the critical defensive mechanisms against oxidative stress in many species. The retina is constantly exposed to reactive oxygen species, and oxidative stress is a major contributor to age-related macular diseases. Moreover, the resulting inflammation and neuronal degeneration are also related to other retinal diseases. The well-known Nrf2 activators, bardoxolone methyl and its derivatives, have been the subject of a number of clinical trials, including those aimed at treating chronic kidney disease, pulmonary arterial hypertension, and mitochondrial myopathies. Recent studies suggest that Nrf2 activation protects the retina from retinal diseases. In particular, this is supported by the finding that Nrf2 knockout mice display age-related retinal degeneration. Moreover, the concept has been validated by the efficacy of Nrf2 activators in a number of retinal pathological models. We have also recently succeeded in generating a novel Nrf2 activator, RS9, using a biotransformation technique. This review discusses current links between retinal diseases and Nrf2 and the possibility of treating retinal diseases by activating the Nrf2 signaling pathway.


Sign in / Sign up

Export Citation Format

Share Document