NQO1 Gene Research Articles

Protective Effect of Pravastatin on Myocardial Ischemia Reperfusion Injury by Regulation of the miR-93/Nrf2/ARE Signal Pathway.

PurposeThis research intended to study the mechanism of pravastatin in myocardial ischemia reperfusion (I/R) injury.Patients and MethodsAltogether 70 male rats were selected and grouped into Sham operation group (Sham group), ischemia reperfusion group (I/R group), pravastatin pretreatment group (I/R+P group), I/R+miR-93-mimics, I/R+P+miR-93-mimics, I/R+Nrf2 siRNA, and I/R+P+Nrf2 siRNA group. The myocardial function of each group was detected.ResultsMyocardial I/R injury could lead to abnormal myocardial enzyme activity, inflammatory reaction and oxidative stress. However, pravastatin could significantly inhibit the activity of myocardial enzymes, alleviate inflammatory reaction and inhibit oxidative stress reaction, thus playing a protective role. Furthermore, cell experiments showed that pravastatin can alleviate the injury of H9C2 myocardial cells caused by I/R, inhibit the apoptosis of myocardial cells, and lead to a significant reduction in pro-apoptotic genes Bax, caspase-3 and caspase-9 transcription levels, an obvious increase in anti-apoptotic gene Bcl-2, and an increase in cell activity. After I/R induced injury, miR-93 level was significantly up-regulated and Nrf2 level was down-regulated. Over-expression of miR-93 or inhibition of Nrf2 expression would lead to further aggravation of I/R myocardial injury, increase the apoptosis rate of cells and decrease the activity of myocardial cells. Pravastatin administration could inhibit miR-93, activate and promote Nrf2 in myocardial tissue, and promote protein expression of downstream regulatory genes HO-1 and NQO1. In the I/R model, pravastatin was given. Over-expression of miR-93 or silencing Nrf2 could reverse the therapeutic effect of pravastatin on I/R.ConclusionPravastatin acts as a protector on myocardial ischemia reperfusion injury by regulating miR-93/Nrf2/ARE signaling pathway.

Oxygen-mediated lung injury in mice lacking the gene for NRF2: Rescue with the cytochrome P4501A-inducer, beta-naphthoflavone (BNF), and differential sex-specific effects

BackgroundAcute respiratory distress syndrome (ARDS) leads to progressive lung injury, which significantly impacts patient morbidity and mortality but may differ clinically between the sexes. Cytochrome P450 (CYP) 1A enzymes are protective against hyperoxic lung injury and may contribute to sex-dependent pathology. NRF2 is a critical transcriptional regulator of antioxidants and loss of NRF2 leads to severe hyperoxic lung injury and mortality in mice. NRF2 deficiencies and polymorphisms have been observed in patients with pulmonary diseases such as chronic obstructive pulmonary disease and severe asthma. No prior studies have evaluated whether there are sex-specific differences in oxygen-mediated lung injury in Nrf2−/− mice and there are few rescue studies. ObjectiveTo test the hypothesis that hyperoxia induces greater lung injury and inflammation in Nrf2−/− mice compared to wild type (WT) that differs between sexes, and that this phenotype will be rescued by the administration of the cytochrome P450 (CYP) 1A inducer beta-naphthoflavone (BNF). Design/MethodsMale and female 8-10-week-old WT or Nrf2−/− C57BL/6 mice were pre-treated with BNF (40 mg/kg) or corn oil control and exposed to hyperoxia (95% O2) for 68 h. Survival, pulmonary edema, neutrophil recruitment, and lung injury scores were evaluated. Gene expression of phase II detoxification enzymes, pulmonary cytokines, and Cyp1a1/2 was quantified. CYP1A1/2 protein expression and catalytic activities were also measured. ResultsHyperoxia exposure greatly reduced survival in Nrf2−/− mice, particularly in females. BNF treatment improved survival by 182.8% in Nrf2−/− females and by 41.4% in Nrf2−/− males as well as in WT females by 85.7%. Females had greater pulmonary edema as measured by lung weight to body weight ratios but was attenuated in all groups except Nrf2−/− females by BNF. Neutrophils doubled in Nrf2−/− lungs compared to WT in hyperoxia but were decreased in BNF-treated females of both genotypes. Pulmonary cytokine gene expression including Il-6 and Tnf-α increased in hyperoxia especially in Nrf2−/− mice and was unaffected by BNF. Pulmonary and hepatic Nqo1 gene expression w-as decreased in Nrf2−/− mice and was largely unaffected by BNF; however pulmonary Ho-1 did not vary significantly between the genotypes and was decreased in WT animals treated with BNF. Activities and protein expression of pulmonary and hepatic CYP1A1/2 were induced via BNF across all groups. Although hepatic Cyp1a2 gene expression was higher in Nrf2−/− males, the catalytic activity was higher in Nrf2−/− females. ConclusionsHyperoxia augmented lung injury in Nrf2−/− mice, and pre-treatment with BNF was protective against mortality and injury, eliminating the sex-dependent survival difference in both genotypes. Our results support the hypothesis that NRF2 protects mice against lung injury, and the fact that BNF rescues the lung injury phenotype in Nrf2−/− mice suggests that augmented CYP1A expression by BNF may contribute to the beneficial effects. Further studies could lead to the development of BNF and other flavonoids for the prevention/treatment of hyperoxic lung injury, particularly in vulnerable patients with relative NRF2 deficiency, regardless of sex.

Antioxidant and Anti-Inflammatory Activities of Safflower (Carthamus tinctorius L.) Honey Extract.

Safflower honey is a unique type of monofloral honey collected from the nectar of Carthamus tinctorius L. in the Apis mellifera colonies of northwestern China. Scant information is available regarding its chemical composition and biological activities. Here, for the first time, we investigated this honey’s chemical composition and evaluated its in vitro antioxidant and anti-inflammatory activities. Basic physicochemical parameters of the safflower honey samples in comparison to established quality standards suggested that safflower honeys presented a good level of quality. The in vitro antioxidant tests showed that extract from Carthamus tinctorius L. honey (ECH) effectively scavenged DPPH and ABTS+ free radicals. In lipopolysaccharides (LPS) activated murine macrophages inflammatory model, ECH treatment to the cells inhibited the release of nitric oxide and down-regulated the expressions of inflammatory-relating genes (iNOS, IL-1β, TNF-α and MCP-1). The expressions of the antioxidant genes TXNRD, HO-1, and NQO-1, were significantly boosted in a concentration-dependent manner. ECH decreased the phosphorylation of IκBα and inhibited the nuclear entry of the NF-κB-p65 protein, in LPS-stimulated Raw 264.7 cells, accompany with the increased expressions of Nrf-2 and HO-1, suggesting that ECH achieved the anti-inflammatory effects by inhibiting NF-κB signal transduction and boosting the antioxidant system via activating Nrf-2/HO-1 signaling. These results, taken together, indicated that safflower honey has great potential into developing as a high-quality agriproduct.

Herbal decoction Divya-Swasari-Kwath attenuates airway inflammation and remodeling through Nrf-2 mediated antioxidant lung defence in mouse model of allergic asthma

Background and purposeAsthma is a chronic respiratory disease orchestrated by immune and structural cells. Identification of novel therapeutic strategies are needed for asthma due to the limitations of existing therapies. We have validated the anti-inflammatory, anti-asthmatic and immunomodulatory therapeutic properties of herbal decoction, Divya-Swasari-Kwath (DSK) using mouse model of ovalbumin (OVA) induced allergic asthma. Methods and resultsHPLC analysis identified the presence of Rutin, Glycyrrchzin, Gallic acid, Cinnamic acid, Chlorogenic acid, Caffeic acid and Piperine as bioactive herbal metabolites in DSK. Therapeutic treatment with herbal decoction DSK significantly alleviated the pathological features of allergic asthma including inflammatory cell accumulation in Broncho-Alveolar Lavage (BAL) fluids, specifically lymphocytes and eosinophils, lung inflammation, oxidative stress, airway remodelling, and pro-inflammatory cytokine levels. H&E analysis of lung tissue sections identified attenuated inflammatory cell infiltration and thickening of bronchial epithelium by DSK. PAS staining and MT staining identified decrease in OVA-induced mucus hyper secretion and peri-bronchial collagen deposition respectively, upon DSK treatment. Treatment with DSK increased the mRNA expression of antioxidative defence gene Nrf-2 and its downstream target genes HO-1 and NQO-1. In the same line, biochemical analysis for the markers of oxidative/antioxidant system confirmed the restoration of activity of Catalase, GPx, SOD and EPO and the levels of GSH, GSSG, MDA and Nitrite in whole lungs. In line with PAS staining, DSK treatment decreased the OVA-induced expression of Muc5AC and Muc5B genes. DSK treatment reduced the steady state mRNA expression levels of IL-6, IL-1β, TNF-α, IL-4, -5, -33, IFN-γ in whole lung; and IL-6, TNF-α and IL-1β protein levels in BALF. ConclusionCollectively, our results suggest that herbal decoction DSK is effective in protecting against allergic airway inflammation and remodelling by regulating anti-oxidant mechanisms. We postulate that DSK could be the potential therapeutic option for allergic asthma management.

Dietary amino acid ergothioneine protects HT22 hippocampal neurons against H2O2-induced neurotoxicity via antioxidative mechanism

BackgroundErgothioneine (EGT) is a naturally occurring amino acid acquired through the dietary intake of foods, mainly mushrooms. This potent antioxidant is a cytoprotectant in several experimental models. However, its neuroprotective activities are scarcely available, especially in the hippocampal region associated with cognition. MethodsIn this study, the neuroprotective activity of EGT was investigated in hydrogen peroxide (H2O2)-induced neurotoxicity in HT22 mouse hippocampal neurons by focusing on antioxidation, mitochondrial functions, and anti-apoptotic activities. ResultsH2O2 drastically reduced the HT22 cells viability accompanied by a significant rise in reactive oxygen species (ROS), reduction of mitochondrial membrane potential (MMP) and adenosine triphosphate (ATP), and increase in apoptotic nuclei. Co-incubation with 1 mM EGT significantly attenuated the H2O2-induced toxicity, reduced the ROS, and decreased the apoptotic nuclei, without affecting the MMP and ATP. EGT significantly increased expression levels of Nrf2, NQO1 and HO-1 antioxidant genes as well as mitochondrial CYC1 gene while Bcl-2 and Bax apoptotic genes were unaffected. ConclusionThis study suggests the potential of EGT as a neuroprotectant in hippocampal neurons mainly through its potent antioxidative activities. EGT could be further explored in vivo considering its effectiveness and safety profile.

The potential impact of trigonelline loaded micelles on Nrf2 suppression to overcome oxaliplatin resistance in colon cancer cells.

Nuclear factor erythroid 2-related factor 2 (Nrf2) has a pivotal role in promoting chemoresistance by regulation of antioxidants and detoxification enzymes. Trigonelline is one of the majoralkaloids inrawcoffee which has been recently introduced as potent inhibitor of Nrf2. This study investigated the role of trigonelline and trigonelline loaded micelles in Nrf2 inhibition to break down oxaliplatin resistance in colon cancer cells. The PCL-PEG-PCL and PLA-PCL-PEG-PCL-PLA copolymers and trigonelline loaded micelles were prepared and characterized for fourier transforms infrared (FTIR), hydrogen nuclear magnetic resonance (1H-NMR), carbon nuclear magnetic resonance (13C-NMR) spectroscopy, particle size, zeta potential, scanning electron microscopy (SEM) and entrapment efficiency. Cell viability and apoptosis were evaluated by using MTT and flow cytometry assays, respectively. Nrf2, MRP1, NQO1, HO-1, Bax, and Bcl2 gene expressions were examined by qRT-PCR. Our results revealed that micelles had spherical shapes with narrow sizes and zeta potential indexes of - 9.06 ± 6.94mV for trigonelline loaded 3Block and - 7.47 ± 6.08mV for trigonelline loaded 5Block micelles. After Nrf2 inhibition by trigonelline, antioxidant response element (ARE) related gene expressions were decreased (p < 0.05) with a significantly higher impact by trigonelline loaded micelles (p < 0.05). Trigonelline loaded micelles also strongly decreased IC50 value of oxaliplatin in resistant colon cancer cells (p < 0.05). Furthermore, trigonelline loaded 5Block micelle increased oxaliplatin-induced apoptosis in a Nrf2/ARE dependent manner. Altogether, the current study suggests that delivery of trigonelline loaded micelles as potent Nrf2 inhibitors can be considered as a promising strategy to overcome oxaliplatin resistance in colon cancer patients.

Quinone Oxidoreductase 2 Serum Level that affecting the Psychotic Disorders of Methamphetamine Abusers

Background: Some evidence suggests that genetic factors contribute to susceptibility to drug abuse such as methamphetamin and that dopamine-quinone produced by dopamine might be involved in the mechanism of symptoms associated with psychotic methamphetamine (MAP). Quinone detoxification is catalyzed by a group of proteins, namely quinone oxidoreductase (NQO). In this study we analyzed serum NQO2 levels by examining ELISA Sandwich in clients who used methamphetamine. Methods: This research is a Case-Control to determine the contribution of NQO2 to the emergence of psychotic disorders due to methamphetamine abuse. The case group is residents who consume methamphetamine with psychotic characteristics, while the control group is clients who consume methamphetamine without psychotic characteristics Results: The mean value of NQO2 gene protein in the Elisa Sandwich examination for the case group was lower than the value of the control group (1,246 < 3,657). The t test showed the value of sig (Equal variances not assumed) = 0,000 that value is less than 0.05 (<0.05), this shows the difference in the value of content protein NQO2 between the case group and the control group. Then the cut-off point of the Receiver Operating Characteristic (ROC) curve in this study is recommended statistically between 1,960 and 2,165, meaning that if the expression value of protein content > 2.165 then the potential for psychotic suffering is great, on the other hand if < 1.960, the potential is small for suffering from psychotics. Conclusion: The protein content of the NQO2 gene in the Elisa Sandwich examination between the case and control groups is different, the case group is lower than the control. While the CURVE ROC (Receiver Operating Characteristic) Cut-Off value is recommended statistically between 1,960 and 2,165.

Lapatinib Activates the Kelch-Like ECH-Associated Protein 1-Nuclear Factor Erythroid 2-Related Factor 2 Pathway in HepG2 Cells.

The receptor tyrosine kinase inhibitor lapatinib, indicated to treat patients with HER2-positive breast cancer in combination with capecitabine, can cause severe hepatotoxicity. Lapatinib is further associated with mitochondrial toxicity and accumulation of reactive oxygen species. The effect of lapatinib on the Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, the major cellular defense pathway against oxidative stress, has so far not been studied in detail. In the present study, we show that lapatinib (2–20 µM) activates the Keap1-Nrf2 pathway in HepG2 cells, a hepatocellular carcinoma-derived cell line, in a concentration-dependent manner upon 24 h of treatment. Lapatinib stabilized the transcription factor Nrf2 at concentrations ≥5 µM and caused its nuclear translocation. Well-established Nrf2 regulated genes (Nqo1, Gsta1, Gclc, and Gclm) were upregulated at lapatinib concentrations ≥10 µM. Furthermore, cellular and mitochondrial glutathione (GSH) levels increased starting at 10 µM lapatinib. As a marker of oxidative stress, cellular GSSG significantly increased at 10 and 20 µM lapatinib. Furthermore, the gene expression of mitochondrial Glrx2 and SOD2 were increased upon lapatinib treatment, which was also observed for the mitochondrial SOD2 protein content. In conclusion, lapatinib treatment for 24 h activated the Keap1-Nrf2 pathway in HepG2 cells starting at 10 μM, which is a clinically relevant concentration. As a consequence, treatment with lapatinib increased the mRNA and protein expression of antioxidative and other cytoprotective genes and induced GSH synthesis, but these measures could not completely block the oxidative stress associated with lapatinib.

Oligosaccharide attenuates aging-related liver dysfunction by activating Nrf2 antioxidant signaling.

Chitosan oligosaccharide (COS) is the depolymerized product of chitosan possessing various biological activities and protective effects against inflammation and oxidative injury. The aim of the present study was to investigate the antioxidant effects of COS supplements on aging‐related liver dysfunction. We found that COS treatment significantly attenuated elevated liver function biomarkers and oxidative stress biomarkers and decreased antioxidative enzyme activities in liver tissues in D‐galactose (D‐gal)‐treated mice. Furthermore, COS treatment significantly upregulated the expression of Nrf2 and its downstream target genes HO‐1, NQO1, and CAT. Moreover, in vitro experiments showed that COS treatment played a vital role in protecting H2O2‐exposed L02 cells against oxidative stress by activating Nrf2 antioxidant signaling. These data indicate that COS could protect against D‐gal‐induced hepatic aging by activating Nrf2 antioxidant signaling, which may provide novel applications for the prevention and treatment of aging‐related hepatic dysfunction.

USP9X prevents AGEs-induced upregulation of FN and TGF-β1 through activating Nrf2-ARE pathway in rat glomerular mesangial cells

Oxidative stress is a key pathological factor for diabetic renal fibrosis by activating TGF-β/Smad pathway in glomerular mesangial cells (GMCs) to promote the synthesis of extracellular matrix such as fibronectin (FN). Nuclear factor-E2-related factor (Nrf2)- anti-oxidant response element (ARE) anti-oxidative pathway has crucial renoprotective effects, and inhibiting ubiquitin-mediated degradation of Nrf2 delays diabetic renal fibrosis development. Ubiquitin-specific protease 9X (USP9X) has close relationship with oxidative stress and TGF-β/Smad pathway, but whether it regulate diabetic renal fibrosis remains unclarified. Here, we found that advanced glycation-end products (AGEs) dose- and time-dependently reduced the protein expression and deubiquitinase activity of USP9X in GMCs. USP9X overexpression attenuated AGEs-induced upregulation of FN, TGF-β1, and Collagen Ⅳ, three fibrosis-related marker proteins, in a deubiquitinase activity-dependent manner. While USP9X depletion with siRNAs further promoted the expressions of those proteins in AGEs-treated GMCs. Under AGEs treatment conditions, USP9X overexpression markedly increased the total and nuclear levels, ARE-binding ability, and transcriptional activity of Nrf2, upregulated the protein expressions of Nrf2 downstream genes HO-1 and NQO1, and eventually reduced the excessive production of ROS. Overexpression of the deubiquitinase catalytically inactive USP9X–C1556S mutant failed to exert such effects. Silencing Nrf2 abolished the renoprotective effects of USP9X. Further study showed that upon AGEs stimulation, Nrf2 transferred into the nucleus and the interaction between USP9X and Nrf2 was weakened. AGEs also increased Nrf2 ubiquitination level, and overexpression of USP9X, instead of USP9X–C1556S, significantly reduced the ubiquitination level of Nrf2. Taken together, USP9X reduced Nrf2 ubiquitination level and promoted Nrf2-ARE pathway activation to prevent the accumulation of extracellular matrix, eventually alleviated the pathological process of diabetic renal fibrosis.

UVA Induced Oxidative Stress Was Inhibited by Paeoniflorin/Nrf2 Signaling or PLIN2.

Photodamages caused by UVA radiation induced oxidative injuries are closely related to photoaging and skin cancer. Paeoniflorin (PF), extracted from the root of Paeonia lactiflora, has been reported to be an effective antioxidant. PLIN2, known as adipose differentiation-related protein, has been previously involved in the regulation of oxidative stress. In this study, we were sought to investigate the photo-protective property of PF and PLIN2 in UVA-radiated human dermal fibroblasts (HDFs). HDFs were pre-treated with PF (800 μM) followed by UVA radiation (22.5 J/cm2). MTS activity, cell apoptosis, ROS, MDA, and SOD were detected, respectively. The expressions of Nrf2, HO-1, NQ-O1, and PLIN2 were determined using RT-qPCR or western blot. Nrf2 was silenced by siRNA, and PLIN2 was overexpressed via lentiviral transduction. Comparing to the UVA radiation, PF pre-treatment could prominently increase the MTS activity, decrease cell apoptosis, reduce the generations of ROS and MDA, increase the activity of SOD and increase the expression of Nrf2 and its target genes HO-1 and NQ-O1. When Nrf2 was knocked down, PF lost above protective properties. In addition, UVA induced oxidative stress led to upregulation of PLIN2 and the latter could be decreased by PF. Overexpression of PLIN2 improved MTS activity and reduced MDA level in HDFs. The combination of PLIN2 overexpression and PF pre-treatment corporately inhibited UVA-induced injury. Besides, we also found that PF and PLIN2 had a compensatory protection against UVA induced oxidative stress. In conclusion, our study demonstrated that UVA induced photodamages could be inhibited by PF via Nrf2/HO-1/NQ-O1 signaling pathway or by PLIN2, and the combination of PLIN2 overexpression and PF played additive effects against UVA-related oxidative stress.

NAD(P)H: quinone oxidoreductase 1 gene rs1800566 polymorphism increases the risk of cervical cancer in a Chinese Han sample: A STROBE-complaint case-control study.

Recently, 2 studies from Thai and American investigated the relationship between NAD(P)H: quinone oxidoreductase 1(NQO1) gene rs1800566 polymorphism and cervical cancer risk and generated contrary results. However, no Chinese reports have addressed this relationship until now. To explore the association between NQO1 gene rs1800566 polymorphism with cervical cancer, we performed a study in a Chinese Han sample.Using a unmatched case-control design, we enrolled 450 cervical cancer patients and 568 controls in the Central Hospital of Wuhan from January 2010 to December 2016. The genotypes were determined by sequencing polymerase chain reaction product. Hardy-Weinberg equilibrium was assessed using the Chi-square test. The univariate and multi-variate logistic regression with odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the association between the NQO1 gene rs1800566 polymorphism and cervical cancer susceptibility.The Chi-square test indicated that significant allele and genotype distributions differences were observed between case group and control group (P < .001). The logistic regression indicated that TT genotype was associated with higher risk of cervical cancer compare with those with the CT or CC genotype (TT vs CC: OR = 2.82, 95%CI: 1.91–4.17, P < .001; TT vs CT: OR = 2.02, 95%CI: 1.36–3.01, P < .001). The effects of NQO1 show dominant model (TT/CT vs CC: OR = 1.67, 95%CI: 1.30–2.15, P < .001) and recessive model (TT vs. CT/CC: OR = 2.43, 95%CI: 1.68–3.52, P < .001). The significant relationship between NQO1 rs1800566 polymorphism and cervical cancer risk was also found in stratified analyses. The cross-over analysis indicated that there are potential interactions between genetic factors and human papillomavirus infection/ contraceptive oral use for the risk of cervical cancer.NQO1 gene rs1800566 polymorphism is associated with elevated risk of cervical cancer in Chinese Han women. The interactions between rs1800566 polymorphism and human papillomavirus infection/ contraceptive oral use further reinforce this association.

Apigenin Protects Mouse Retina against Oxidative Damage by Regulating the Nrf2 Pathway and Autophagy.

Oxidative stress is a critical factor in the pathology of age-related macular degeneration (AMD). Apigenin (AP) is a flavonoid with an outstanding antioxidant activity. We had previously observed that AP protected APRE-19 cells against oxidative injury in vitro. However, AP has poor water and fat solubility, which determines its low oral bioavailability. In this study, we prepared the solid dispersion of apigenin (AP-SD). The solubility and dissolution of AP-SD was significantly better than that of the original drug, so the oral bioavailability in rats was better than that of the original drug. Then, the effects of AP-SD on the retina of a model mouse with dry AMD were assessed by fundus autofluorescence (FAF), optical coherence tomography (OCT), and electron microscopy; the results revealed that AP-SD alleviated retinopathy. Further research found that AP-SD promoted the nuclear translocation of Nrf2 and increased expression levels of the Nrf2 and target genes HO-1 and NQO-1. AP-SD enhanced the activities of SOD and GSH-Px and decreased the levels of ROS and MDA. Furthermore, AP-SD upregulated the expressions of p62 and LC3II in an Nrf2-dependent manner. However, these effects of AP-SD were observed only in the retina of Nrf2 WT mice, not in Nrf2 KO mice. In addition, the therapeutic effect of AP-SD was dose dependent, and AP did not work. In conclusion, AP-SD significantly enhanced the bioavailability of the original drug and reduced retinal oxidative injury in the model mouse of dry AMD in vivo. The results of the underlying mechanism showed that AP-SD upregulated the expression of antioxidant enzymes through the Nrf2 pathway and upregulated autophagy, thus inhibiting retinal oxidative damage. AP-SD may be a potential compound for the treatment of dry AMD.

Transcriptome Profiling Reveals Indoxyl Sulfate Should Be Culpable of Impaired T Cell Function in Chronic Kidney Disease

Introduction: Chronic inflammation and immune system dysfunction have been evaluated as major factors in the pathogenesis of chronic kidney disease (CKD), contributing to the high mortality rates observed in these populations. Uremic toxins seem to be the potential “missing link.” Indoxyl sulfate (IS) is one of the protein-bound renal toxins. It participates in multiple pathologies of CKD complications, yet its effect on immune cell has not been studied. This study aimed to explore the genome-wide expression profile in human peripheral blood T cells under stimulation by IS.Methods: In this study, we employed RNA-sequencing transcriptome profiling to identify differentially expressed genes (DEGs) responding to IS stimulation in human peripheral T cells in vitro. Flow cytometry and western blot were used to verify the discovery in RNA-sequencing analysis.Results: Our results yielded a total of 5129 DEGs that were at least twofold up-regulated or down-regulated significantly by IS stimulation and half of them were concentration-specific. Analysis of T cell functional markers revealed a quite different transcription profile under various IS concentration. Transcription factors analysis showed the similar pattern. Aryl hydrocarbon receptor (AhR) target genes CYP1A1, CYP1B1, NQO1, and AhRR were up-regulated by IS stimulation. Pro-inflammatory genes TNF-α and IFN-γ were up-regulated as verified by flow cytometry analysis. DNA damage was induced by IS stimulation as confirmed by elevated protein level of p-ATM, p-ATR, p-BRCA1, and p-p53 in T cells.Conclusion: The toxicity of IS to T cells could be an important source of chronic inflammation in CKD patients. As an endogenous ligand of AhR, IS may influence multiple biological functions of T cells including inflammatory response and cell cycle regulation. Further researches are required to promulgate the underling mechanism and explore effective method of reserving T cell function in CKD.

Atractylenolide II prevents radiation damage via MAPKp38/Nrf2 signaling pathway

Ionizing radiation (IR) can act as a negative factor for human homeostasis, by causing and even aggravating a series of pathological conditions. To protect the intactness of normal tissues, effective anti-radiation drugs are urgently needed for alleviating the outcomes of radioactive damage. In this study, we demonstrate that atractylenolide II (ATR II), a sesquiterpenoid monomer extracted from traditional Chinese medicine atractylodes macrocephala, can markedly suppress IR damage by promoting the expression of antioxidant factors heme oxygenase-1 (HO-1) and NAD(P)H dehydrogenase quinone oxido-reductase 1 (NQO-1), which are mediated by nuclear factor-erythroid 2-like 2 (Nrf2) signaling pathway. Furthermore, here we reveal that ATR II effectively upregulates the expression of mitogen-activated protein kinase p38 (MAPKp38), which also acts as a regulator of Nrf2 signaling cascade. Indeed, treatment with a MAPKp38 inhibitor can significantly downregulate the expression of Nrf2 and its downstream target genes HO-1 and NQO-1 and, consequently, abolish the protective effect of ATR II against IR. Consistently, ATR II also has a protective function against IR-induced damage in animal models. In conclusion, our study provides an unexpected function of ATR II in preventing IR-induced damage by modulating MAPKp38/Nrf2 signaling pathway.

Nrf2 and Ferroptosis: A New Research Direction for Neurodegenerative Diseases.

Ferroptosis is a kind of regulated cell death (RCD) caused by the redox state disorder of intracellular microenvironment controlled by glutathione (GSH) peroxidase 4 (GPX4), which is inhibited by iron chelators and lipophilic antioxidants. In addition to classical regulatory mechanisms, new regulatory factors for ferroptosis have been discovered in recent years, such as the P53 pathway, the activating transcription factor (ATF)3/4 pathway, Beclin 1 (BECN1) pathway, and some non-coding RNA. Ferroptosis is closely related to cancer treatment, neurodegenerative diseases, ischemia–reperfusion of organ, neurotoxicity, and others, in particular, in the field of neurodegenerative diseases treatment has aroused people’s interest. The nuclear factor E2 related factor 2 (Nrf2/NFE2L2) has been proved to play a key role in neurodegenerative disease treatment and ferroptosis regulation. Ferroptosis promotes the progression of neurodegenerative diseases, while the expression of Nrf2 and its target genes (Ho-1, Nqo-1, and Trx) has been declined with aging; therefore, there is still insufficient evidence for ferroptosis and Nrf2 regulatory networks in the field of neurodegenerative diseases. In this review, we will provide a brief overview of ferroptosis regulatory mechanisms, as well as an emphasis on the mechanism of Nrf2 regulating ferroptosis. We also highlight the role of ferroptosis and Nrf2 during the process of neurodegenerative diseases and investigate a theoretical basis for further research on the relationship between Nrf2 and ferroptosis in the process of neurodegenerative diseases treatment.

Low dose of luteolin activates Nrf2 in the liver of mice at start of the active phase but not that of the inactive phase.

A flavone luteolin has various health-promoting activities. Several studies reported that high dose of luteolin activates the Nrf2/ARE pathway in the liver. However, the effect of the low dose of luteolin that can be taken from a dietary meal on the Nrf2 activation remain unclear. It is expected that the flavonoid metabolism possesses a circadian rhythm, since nutritional metabolism processes daily cycle. In this study we investigated whether an administration affects the Nrf2 activation. ICR mice were orally administered 0.01-10 mg/kg body weight of luteolin once a day for 7 days at two time-points: at the start of active phase (ZT12) or at that of inactive phase (ZT0). Luteolin increased the nuclear translocation of Nrf2, resulting in the increases in its target gene products HO-1 and NQO1 at ZT12 but not at ZT0. The expression level of Nrf2 was lower at ZT12 than at ZT0 in the liver. We also found that the level of luteolin aglycon in the plasma is higher at ZT12 than at ZT0. These results suggest that the low dose of luteolin can activate Nrf2 pathway and the aglycon form of luteolin may mainly contribute to activate the Nrf2 pathway at ZT12 in the liver.

Metformin attenuates lead‐induced inflammatory and apoptotic lung injury through modulation of P53 and TNF‐α pathways in rats

Exposure to heavy metals, such as Lead (Pb) is a matter of growing concern and potential risk factor for developing inflammatory lung diseases. The aim of this study was to a) investigate the protective effect of metformin against Pb‐induced lung injury in rat and b) investigate the underlying mechanisms specifically the role of oxidative stress, inflammation and apoptosis. For this purpose, twenty‐four adult male Wistar albino rats weighing about 230 gm were randomly distributed into six study groups of four rats each. The first group received normal saline (0.5 ml/kg/day) for 6 consecutive days and served as a a Control. The second group received metformin (500 mg/kg) for 6 consecutive days. The third and fourth groups received a single dose of normal saline (0.5 ml/kg/day) for 3 consecutive days followed by lead nitrate (Pb) (25 and 50 mg/kg, i.p.) for 3 consecutive days, respectively. The fifth and sixth groups received metformin (500 mg/kg) for 3 consecutive days followed by Pb 25 and 50 mg/kg, i.p. plus metformin 500 mg/kg for additional 3 consecutive days, respectively. One day after the last dose, animals were a and blood samples were collected via cardiac puncture for determination the levels of Pb. Rats lung tissues were excised and processed for histopathological examination, determination the levels of mRNA and protein expression of target genes, Analysis of apoptosis and TNF‐α production were determined by flow cytometer. Our results showed that exposure to Pb caused induction of inflammatory cells infiltration, cell apoptosis, modulation of genes involving in inflammation and oxidation, induction of p53 and TNF‐α were demonstrated in Pb‐induced lung injury. Administration of metformin 500 mg/kg for 6 days resulted in a protective effect on the Pb‐induced inflammatory lung injury through induction of the expression levels of NQO1, SOD, HO‐1, and p53 genes. In addition, metformin treatment significantly reduced the production of TNF‐α and expression of IL‐6 while induced the expression of IL‐10 in Pb‐treated groups. In conclusion, these observations suggest that metformin processes anti‐inflammatory, antiapoptotic and the induction of antioxidants properties against Pb‐induced lung injuries.

Bacterial Endotoxin Induces Oxidative Stress and Reduces Milk Protein Expression and Hypoxia in the Mouse Mammary Gland.

The aim of this study was to investigate the mechanisms underlying the reduced milk production during mastitis. We hypothesized that bacterial endotoxin induces hypoxia, oxidative stress, and cell apoptosis while inhibiting milk gene expression in the mammary gland. To test this hypothesis, the left and right sides of the 4th pair of mouse mammary glands were alternatively injected with either lipopolysaccharide (LPS, E. coli 055: B5, 100 μL of 0.2 mg/mL) or sterile PBS through the teat meatus 3 days postpartum. At 10.5 and 22.5 h postinjection, pimonidazole HCl, a hypoxyprobe, was injected intraperitoneally. At 12 or 24 h after the LPS injection, the 4th glands were individually collected (n = 8) and analyzed. LPS treatment induced mammary inflammation at both 12 and 24 h but promoted cell apoptosis only at 12 h. Consistently, H2O2 content was increased at 12 h (P < 0.01), but dropped dramatically at 24 h (P < 0.01) in the LPS-treated gland. Nevertheless, the total antioxidative capacity in tissue tended to be decreased by LPS at both 12 and 24 h (P = 0.07 and 0.06, respectively). In agreement with these findings, LPS increased or tended to increase the mRNA expression of antioxidative genes Nqo1 at 12 h (P = 0.05) and SLC7A11 at 24 h (P = 0.08). In addition, LPS inhibited mammary expression of Csn2 and Lalba across time and protein expression of Csn1s1 at 24 h (P < 0.05). Furthermore, hypoxyprobe staining intensity was greater in the alveoli of the PBS-treated gland than the LPS-treated gland at both 12 and 24 h, demonstrating a rise in oxygen tension by LPS treatment. In summary, our observations indicated that while intramammary LPS challenge incurs inflammation, it induces oxidative stress, increases cell apoptosis and oxygen tension, and differentially inhibits the milk protein expression in the mammary gland.

Liraglutide ameliorates obesity-related nonalcoholic fatty liver disease by regulating Sestrin2-mediated Nrf2/HO-1 pathway

Liraglutide, a glucagon-like peptide 1 (GLP-1) analogue, could reverse NAFLD-induced liver damage by improving metabolic profiles, but the exact molecular mechanism has not been elucidated. Sestrin2 is a novel antioxidant protein, essential for regulating metabolic homeostasis. However, whether sestrin2-mediated redox balance participated in the protective effects of liraglutide against NAFLD is still elusive. The aim of the study was to determine whether liraglutide could ameliorate NAFLD by increasing Sestrin2-mediated signaling in obese mice. Following a normal diet or high fat diet (HFD) for 8 weeks, male C57BL/6 mice were treated with or without liraglutide for 4 weeks. Function and histopathology of liver were conducted to evaluate liver injury. Sestrin2-related AMPK and Nrf2/HO-1 pathway were examined. Antioxidative and inflammatory genes and were determined. HFD mice displayed significantly increased body weight, fat mass, lipids levels and impaired glucose homeostasis with reduced glucose tolerance and insulin sensitivity. Metabolic profiles, hepatic injury, and hepatic lipid accumulation from HFD mice were improved by liraglutide treatment. Liraglutide enhanced Sestrin2, phosphorylated AMPK, Nrf2, and HO-1 protein levels. Additionally, Liraglutide treatment increased mRNA levels of Sestrin2, Nrf2, HO-1 and down-stream genes catalase, GCLM and NQO1, but reduced malondialdehyde and TNF-α levels. Our findings indicated that liraglutide ameliorated obesity-related NAFLD through upregulating Sestrin2-mediated Nrf2/HO-1 pathway.