MitoQ Modulates Lipopolysaccharide-Induced Intestinal Barrier Dysfunction via Regulating Nrf2 Signaling

Background. Gut barrier dysfunction with alterant mucosal permeability during sepsis is a challenge problem in clinical practice. Intestinal epithelial cells (IECs) are strongly involved in mucosal oxidative stress and inflammatory response. The current study aimed at investigating the effect of MitoQ, a mitochondrial targeted antioxidant, in the treatment of intestinal injury and its potential mechanism during sepsis. Methods. 30 minutes before sepsis induction by lipopolysaccharide (LPS) treatment, mice were treated with MitoQ. Intestinal histopathology, mucosal permeability, inflammatory cytokines, and mucosal barrier proteins were evaluated in the present study. Results. MitoQ pretreatment significantly decreased the levels of plasma diamine oxidase, D-lactate, and intestinal histological damage and markedly restored the levels of tight junction proteins (ZO-1 and occludin) following LPS challenge. Furthermore, MitoQ inhibited the LPS-induced intestinal oxidative stress and inflammatory response, evidenced by increased levels of intestinal superoxide dismutase and glutathione, and decreased levels of intestinal IL-1, IL-6, TNF-α, and nitric oxide levels. Mechanically, we found that MitoQ inhibited the oxidative stress via activating nuclear factor E2-related factor 2 (Nrf2) signaling pathway and its downstream antioxidant genes, including HO-1, NQO-1, and GCLM. Conclusions. MitoQ exerts antioxidative and anti-inflammatory effects against sepsis-associated gut barrier injury by promoting Nrf2 signaling pathway.

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Cytoprotective Effect of Ligustrum robustum Polyphenol Extract against Hydrogen Peroxide-Induced Oxidative Stress via Nrf2 Signaling Pathway in Caco-2 Cells

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2019/5026458 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Jiayi Chen ◽

Fangting He ◽

Sijing Liu ◽

Tao Zhou ◽

Saira Baloch ◽

...

Keyword(s):

Oxidative Stress ◽

Hydrogen Peroxide ◽

Signaling Pathway ◽

Total Phenolic ◽

Heme Oxygenase 1 ◽

Related Factor ◽

Cytoprotective Effect ◽

Quinone Oxidoreductase ◽

Antioxidant Genes ◽

Nrf2 Signaling Pathway

Ligustrum robustum is a traditional herbal tea that is widely distributed in southwest China. The health effects of L. robustum are characteristics of clearing heat, antioxidant, inducing resurgence, and improving digestion. However, the molecular mechanisms related to these effects, particularly the antioxidant mechanism, have been seldom reported. The objective of this study was to assess antioxidative capacity of L. robustum, and its protective effects and mechanisms against hydrogen peroxide (H2O2) - induced toxicity in Caco-2 cells. Total phenolic contents, free radical scavenging activity, and reducing capacity of L. robustum were measured. The effects of L. robustum on the cell viability and antioxidant defense system were explored. The expression of nuclear factor E2 related factor 2 (Nrf2) and antioxidant genes: quinone oxidoreductase 1 (NQO1), heme oxygenase-1 (HO-1), and glutamate cysteine ligase (GCL) were analyzed by western blot and qPCR. Pretreatment of L. robustum could significantly reduce H2O2-induced toxicity, decrease the level of reactive oxygen species (ROS) and malondialdehyde (MDA), and increase the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and glutathione reductase (GR). By activating the expression of Nrf2 and antioxidant genes (NQO1, HO-1, and GCL), L. robustum exerts cytoprotective effect in Caco-2 cells dealt with H2O2. Therefore, the well-established model of Caco-2 cells demonstrates that L. robustum may modulate the cytoprotective effect against the H2O2-induced oxidative stress through the Nrf2 signaling pathway.

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Nrf2 Activation Attenuates Acrylamide-Induced Neuropathy in Mice

International Journal of Molecular Sciences ◽

10.3390/ijms22115995 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5995

Author(s):

Chand Basha Davuljigari ◽

Frederick Adams Ekuban ◽

Cai Zong ◽

Alzahraa A. M. Fergany ◽

Kota Morikawa ◽

...

Keyword(s):

Oxidative Stress ◽

Signaling Pathway ◽

Messenger Rna ◽

Hepatic Necrosis ◽

Related Factor ◽

Necrosis Factor Alpha ◽

Adult Mice ◽

Nrf2 Signaling Pathway ◽

Antioxidant Proteins ◽

Oxide Synthase

Acrylamide is a well characterized neurotoxicant known to cause neuropathy and encephalopathy in humans and experimental animals. To investigate the role of nuclear factor erythroid 2-related factor 2 (Nrf2) in acrylamide-induced neuropathy, male C57Bl/6JJcl adult mice were exposed to acrylamide at 0, 200 or 300 ppm in drinking water and co-administered with subcutaneous injections of sulforaphane, a known activator of the Nrf2 signaling pathway at 0 or 25 mg/kg body weight daily for 4 weeks. Assessments for neurotoxicity, hepatotoxicity, oxidative stress as well as messenger RNA-expression analysis for Nrf2-antioxidant and pro-inflammatory cytokine genes were conducted. Relative to mice exposed only to acrylamide, co-administration of sulforaphane protected against acrylamide-induced neurotoxic effects such as increase in landing foot spread or decrease in density of noradrenergic axons as well as hepatic necrosis and hemorrhage. Moreover, co-administration of sulforaphane enhanced acrylamide-induced mRNA upregulation of Nrf2 and its downstream antioxidant proteins and suppressed acrylamide-induced mRNA upregulation of tumor necrosis factor alpha (TNF-α) and inducible nitric oxide synthase (iNOS) in the cerebral cortex. The results demonstrate that activation of the Nrf2 signaling pathway by co-treatment of sulforaphane provides protection against acrylamide-induced neurotoxicity through suppression of oxidative stress and inflammation. Nrf2 remains an important target for the strategic prevention of acrylamide-induced neurotoxicity.

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Ganoderic Acid D Protects Human Amniotic Mesenchymal Stem Cells against Oxidative Stress-Induced Senescence through the PERK/NRF2 Signaling Pathway

Oxidative Medicine and Cellular Longevity ◽

10.1155/2020/8291413 ◽

2020 ◽

Vol 2020 ◽

pp. 1-18

Author(s):

Yan Xu ◽

Huan Yuan ◽

Yi Luo ◽

Yu-Jie Zhao ◽

Jian-Hui Xiao

Keyword(s):

Oxidative Stress ◽

Stem Cells ◽

Signaling Pathway ◽

Adult Stem Cells ◽

Telomerase Activity ◽

Related Factor ◽

Dependent Manner ◽

Ganoderic Acid ◽

Nrf2 Signaling Pathway

Aging is an important risk factor in the occurrence of many chronic diseases. Senescence and exhaustion of adult stem cells are considered as a hallmark of aging in organisms. In this study, a senescent human amniotic mesenchymal stem cell (hAMSC) model subjected to oxidative stress was established in vitro using hydrogen peroxide. We investigated the effects of ganoderic acid D (GA-D), a natural triterpenoid compound produced from Ganoderma lucidum, on hAMSC senescence. GA-D significantly inhibited β-galactosidase (a senescence-associated marker) formation, in a dose-dependent manner, with doses ranging from 0.1 μM to 10 μM, without inducing cytotoxic side-effects. Furthermore, GA-D markedly inhibited the generation of reactive oxygen species (ROS) and the expression of p21 and p16 proteins, relieved the cell cycle arrest, and enhanced telomerase activity in senescent hAMSCs. Furthermore, GA-D upregulated the expression of phosphorylated protein kinase R- (PKR-) like endoplasmic reticulum kinase (PERK), peroxidase III (PRDX3), and nuclear factor-erythroid 2-related factor (NRF2) and promoted intranuclear transfer of NRF2 in senescent cells. The PERK inhibitor GSK2656157 and/or the NRF2 inhibitor ML385 suppressed the PERK/NRF2 signaling, which was activated by GA-D. They induced a rebound for the generation of ROS and β-galactosidase-positive cells and attenuated the differentiation capacity. These findings suggest that GA-D retards hAMSC senescence through activation of the PERK/NRF2 signaling pathway and may be a promising candidate for the discovery of antiaging agents.

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Effect of fluoride on PERK-Nrf2 signaling pathway in mouse ameloblasts

Human & Experimental Toxicology ◽

10.1177/0960327119842273 ◽

2019 ◽

Vol 38 (7) ◽

pp. 833-845

Author(s):

X Zhou ◽

Z Chen ◽

W Zhong ◽

R Yu ◽

L He

Keyword(s):

Oxidative Stress ◽

Er Stress ◽

Signaling Pathway ◽

Nuclear Import ◽

Target Genes ◽

Dental Fluorosis ◽

Related Factor ◽

Dependent Manner ◽

Nrf2 Signaling Pathway ◽

Glutamylcysteine Synthetase

In the development of dental fluorosis, oxidative stress is considered as the key mechanism. Endoplasmic reticulum (ER) stress can induce oxidative stress and activate the important antioxidative factor nuclear factor erythroid 2-related factor 2 (Nrf2) in a PKR-like ER kinase (PERK)-dependent manner, but combining ER stress and oxidative stress, the role of PERK-Nrf2 signaling pathway involved in fluoride-regulated ameloblasts is not fully defined. Here, we studied the effect of fluoride on PERK-Nrf2 signaling pathway in mouse ameloblasts. We found that low-dose and continuous fluoride exposure increased binding immunoglobulin protein expression and activated PERK–activating transcription factor 4 signaling pathway. Meanwhile, the expression of Nrf2 and its target genes (glutamylcysteine synthetase and glutathione S-transferase-P1) enhanced following ER stress. Tunicamycin increased the expression of PERK, leading to Nrf2 nuclear import, and tauroursodeoxycholate suppressed Nrf2 activation through PERK during ER stress, indicating that PERK activation is required for Nrf2 nuclear entry. Furthermore, tert-butylhydroquinone triggered the overexpression of Nrf2 to reduce ER stress, but luteolin inhibited Nrf2 nuclear localization to elevate ER stress. In summary, this study proved that fluoride under certain dose can induce ER stress and promote Nrf2 nuclear import via PERK activation and suggested that antioxidation mechanism mediated by PERK-Nrf2 can alleviate fluoride-induced ER stress effectively.

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Zinc is essential for the transcription function of the PGC-1α/Nrf2 signaling pathway in human primary endometrial stromal cells

AJP Cell Physiology ◽

10.1152/ajpcell.00152.2019 ◽

2020 ◽

Vol 318 (3) ◽

pp. C640-C648 ◽

Cited By ~ 2

Author(s):

Xiaodan Lu ◽

Qiang Zhang ◽

Li Xu ◽

Xiuying Lin ◽

Jianhua Fu ◽

...

Keyword(s):

Oxidative Stress ◽

Signaling Pathway ◽

Stromal Cells ◽

Receptor Interaction ◽

Peroxisome Proliferator ◽

Related Factor ◽

Stem Cell Markers ◽

Endometrial Stromal Cells ◽

Nrf2 Signaling Pathway

Zinc (Zn) has antioxidant effect in different types of organs and is closely associated with human health. Endometrial receptivity is one of the most important factors in the embryo implantation and development. However, the regulatory mechanism of Zn in endometrium tissue is still unclear. In the study, we found that plasma Zn level is significantly associated with female infertility, which severely affects female reproductive health. Primary endometrial stromal cells were isolated from female endometrium and cultured in the laboratory. Zn chelator TPEN treatment reduced the expression of stem cell markers CD73, CD90, and CD105 and generated reactive oxygen species in endometrial stromal cells. However, pretreatment of Zn (zinc sulfate) is able to prevent TPEN-induced oxidative stress in vitro. By transcriptional profiling and gene ontology analysis, we found that Zn increased the cellular pluripotency signaling and extracellular matrix-receptor interaction, but reduced autophagy, endocytosis, and the nitrogen metabolism pathway. We further discovered the antioxidant function of Zn through the peroxisome proliferator-activated receptor gamma coactivator 1α/nuclear factor erythroid-2-related factor signaling pathway in endometrial stromal cells. Zn supplementation may open up an effective therapeutic approach for patients with oxidative stress-related endometrial diseases.

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Estradiol valerate enhances cardiac function via the Nrf2 signaling pathway to protect against oxidative stress by the Nrf2 signaling pathway in an ovariectomized rat model

Current Pharmaceutical Design ◽

10.2174/1381612827666210927162612 ◽

2021 ◽

Vol 27 ◽

Author(s):

Xin Qian ◽

Jiao Wang ◽

Minghui Cai ◽

Haijuan Sun ◽

Han Xu ◽

...

Keyword(s):

Oxidative Stress ◽

Cardiac Function ◽

Signaling Pathway ◽

Left Ventricular ◽

Estradiol Valerate ◽

Sham Operation ◽

Antioxidant Genes ◽

Bilateral Ovariectomy ◽

Increased Risk ◽

Nrf2 Signaling Pathway

Background: The increased risk of cardiovascular disease (CVD) in postmenopausal women and ovariectomized patients suggests that estrogen has a protective effect on cardiac function. Oxidative stress is the main cause of CVD, and the cellular defensive Nrf2 antioxidant pathway plays a protective role in various pathologies. However, the regulation of Nrf2 by estrogen has received little attention. Objective: The present study aimed to investigate the role of Nrf2 in the effect of estrogen on the cardiac function. Method:: In the present study, female SD rats were divided into three groups as follows: sham operation (SHAM), bilateral ovariectomy (OVX) and bilateral ovariectomy with estradiol valerate (EV) supplementation (OVX+EV). Vaginal smears and E2 concentrations were used to confirm model success. We compared cardiac morphology and function by echocardiography and HE staining. The levels of oxidative stress markers and antioxidant enzymes as well as protein expression of antioxidant genes were evaluated by Western blotting and immunohistochemistry. Results: Our results showed that supplementation with estrogen restored the parameters to some extent. Left ventricular end diastolic diameter at diastolic （LVID;d） and left ventricular volume at diastolic (LV vol;d) increased but MV E wave/A wave (E/A) significantly decreased. The oxidative stress indicators (malondialdehyde) increased, and the antioxidant activity indicators, such as superoxide dismutase (SOD) and catalase (CAT), decreased. Further, the expression of most Nrf2 antioxidant pathway-related proteins in the heart decreased after ovariectomy. Conclusion: The present study demonstrated that estrogen may protect cardiac function by regulating antioxidant capacity through the Nrf2 pathway.

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Protective effect of CDDO-imidazolide against intestinal ischemia/reperfusion injury in mice

European Journal of Inflammation ◽

10.1177/2058739218802681 ◽

2018 ◽

Vol 16 ◽

pp. 205873921880268 ◽

Cited By ~ 2

Author(s):

Youqun Huang ◽

Mulin Ye ◽

Chunlin Wang ◽

Zhenfen Wang ◽

Weiping Zhou

Keyword(s):

Intestinal Ischemia ◽

Ischemia Reperfusion ◽

Regulatory Subunit ◽

Rank Test ◽

Related Factor ◽

Model Group ◽

Barrier Dysfunction ◽

Antioxidant Genes ◽

Nrf2 Signaling Pathway ◽

Intestinal Ischemia Reperfusion

Intestinal ischemia/reperfusion (I/R) is life-threatening and challenging in clinical practice. CDDO-imidazolide (CDDO-Im) is therapeutic in alleviating I/R injury. Nevertheless, there is a lack of investigation on the effects of CDDO-Im on intestinal I/R. Mice were randomly divided into four groups: (a) the sham group, (b) the CDDO-Im group, (c) the I/R group, and (d) the I/R + CDDO-Im group. Intestinal I/R was performed by clamping arteria mesenteric anterior for 45 min, followed by 24 h reperfusion. In addition, Kaplan–Meier method and the log-rank test were used to compare the survival rates among groups by observing for 24 h. Intestinal I/R in model group demonstrated severe injury of the intestinal mucosa, lung, kidney, and liver. The intestinal mucosal damage and intestinal barrier dysfunction were obviously attenuated in CDDO-Im-treated group compared with the model group. Also, preconditioning with CDDO-Im reduced pulmonary, hepatic and renal damage, and decreased oxidative stress (malondialdehyde (MDA), superoxide dismutase (SOD), and NO) and pro-inflammatory responses (tumor necrosis factor (TNF-α), interleukin 1β (IL-1β), and interleukin 6 (IL-6)) following I/R injury. Furthermore, we also observed that these protective properties of CDDO-Im were accomplished by the activation of nuclear factor E2-related factor 2 (Nrf2) signaling pathway and upregulation of its downstream antioxidant genes, including heme oxygenase (HO-1), NQO-1, and glutamate–cysteine ligase regulatory subunit (GCLM). Our data suggest that CDDO-Im exerts a beneficial effect on intestinal I/R-associated mucosal barrier dysfunction and distant organ injuries.

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The Effects of Naringin on Cigarette Smoke-Induced Dynamic Changes in Oxidation/Antioxidant System in Lung of Mice

Natural Product Communications ◽

10.1177/1934578x20947233 ◽

2020 ◽

Vol 15 (8) ◽

pp. 1934578X2094723

Author(s):

Pan Chen ◽

Ziting Xiao ◽

Hao Wu ◽

Yonggang Wang ◽

Weiwei Su ◽

...

Keyword(s):

Oxidative Stress ◽

Signaling Pathway ◽

Cigarette Smoke ◽

Antioxidant System ◽

Antioxidant Systems ◽

Heme Oxygenase 1 ◽

Related Factor ◽

Dynamic Changes ◽

Tnf Α ◽

Nrf2 Signaling Pathway

Naringin possesses strong antioxidative activity and can protect against some respiratory diseases. Oxidative stress is thought to be a major factor in the development of many tobacco-caused diseases. The nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway plays a critical role in the regulation of oxidative stress. The dynamic changes in the antioxidant system in the lung that are induced by cigarette smoke (CS) are not well investigated, and how naringin affects these changes remains unknown. This study aimed to investigate the dynamic changes between the oxidation and antioxidant systems resulting from CS exposure and the effects of naringin on these changes in mice. Mice were chronically exposed to CS for 30 days. The levels of malondialdehyde (MDA), glutathione (GSH), interleukin (IL)-6, and tumor necrosis factor-alpha (TNF-α); the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px); and the expressions of Nrf2, heme oxygenase-1 (HO-1), and nicotinamide adenine dinucleotide phosphate quinone dehydrogenase 1 (NQO1) in lung tissue were measured on days 2, 7, and 30. The levels of MDA, GSH, IL-6, and TNF-α in the lung were found to increase throughout the exposure. SOD and GSH-Px activities showed an increase on day 2 and a decrease on days 7 and 30. The messenger ribonucleic acid expressions of Nrf2, HO-1, and NQO1 were elevated on day 2 and decreased on day 7; Nrf2 and HO-1 expressions were continually decreased, but NQO1 expression was increased again, on day 30. Naringin restored the levels of these biochemical indices to normal throughout the experiment, suggesting that naringin protected against the CS-induced oxidative damage by suppressing the increase of antioxidants resulting from the early stage of CS exposure, as well as inhibiting the depletion of antioxidants due to long-term oxidative stress. Naringin also suppressed lung inflammation by inhibiting IL-6 and TNF-α. These results indicate that naringin possesses a powerful ability to maintain the balance of the oxidation/antioxidant system in the lung when subjected to CS exposure, probably by regulating the Nrf2 signaling pathway.

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Dandelion Extract Alleviated Lipopolysaccharide-Induced Oxidative Stress through the Nrf2 Pathway in Bovine Mammary Epithelial Cells

Toxins ◽

10.3390/toxins12080496 ◽

2020 ◽

Vol 12 (8) ◽

pp. 496 ◽

Cited By ~ 1

Author(s):

Yawang Sun ◽

Yongjiang Wu ◽

Zili Wang ◽

Juncai Chen ◽

You Yang ◽

...

Keyword(s):

Oxidative Stress ◽

Epithelial Cells ◽

Signaling Pathway ◽

Mammary Epithelial Cells ◽

Mammary Epithelial ◽

Epithelial Cell Line ◽

Related Factor ◽

Nrf2 Pathway ◽

Bovine Mammary Epithelial Cells ◽

Nrf2 Signaling Pathway

In practical dairy production, cows are frequently subjected to inflammatory diseases, such as high-grain diet-induced subacute ruminal acidosis (SARA) as well as mastitis and metritis. Under the circumstances, lipopolysaccharide (LPS) induces oxidative stress within the cow and in the mammary epithelial cells. It has implications in practical production to alleviate oxidative stress and to optimize the lactational function of the mammary epithelial cells. This study thus aimed to investigate the antioxidative effects of dandelion aqueous extract (DAE) on LPS-induced oxidative stress and the mechanism of DAE as an antioxidant to alleviate oxidative stress through the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway in the bovine mammary epithelial cell line MAC-T cells. The cells were cultured for 48 h in six treatments including control (without LPS and DAE), LPS (100 ng/mL), DAE10 (100 ng/mL LPS and 10 μg/mL DAE), DAE50 (100 ng/mL LPS and 50 μg/mL DAE), DAE100 (100 ng/mL LPS and 100 μg/mL DAE), and DAE200 (100 ng/mL LPS and 200 μg/mL DAE), respectively. The results showed that cell viability was reduced by LPS, and the adverse effect of LPS was suppressed with the supplementation of DAE. Lipopolysaccharide-induced oxidative stress through enhancing reactive oxygen species (ROS) production, resulted in increases in oxidative damage marker concentrations, while 10 and 50 μg/mL DAE alleviated the LPS-induced oxidative stress via scavenging cellular ROS and improving antioxidant enzyme activity. The upregulation of antioxidative gene expression in DAE treatments was promoted through activating the Nrf2 signaling pathway, with DAE at a concentration of 50 μg/mL exhibiting the highest effect. Overall, DAE acted as an effective antioxidant to inhibit LPS-induced oxidative stress and as a potential inducer of the Nrf2 signaling pathway.

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