Activation Of Transcription Factor Nrf2 Research Articles

Activation of Transcription Factor Nrf2 in HeLa Cells under the Action of Nitrosyl Iron Complex with N-Ethylthiourea.

We studied the effect of an NO donor, nitrosyl iron complex with N-ethylthiourea, on Nrf2-dependent antioxidant system activation of tumor cells in vitro. The complex increased intracellular accumulation of Nrf2 transcription factor and induced its nuclear translocation. It was shown that both heme oxygenase-1 gene and protein expression increased significantly under the influence of the complex. Nrf2 activation was accompanied by a decrease in the intracellular accumulation of proinflammatory transcription factor NF-κB p65 subunit and expression of its target genes. The cytotoxic effect of N-ethylthiourea leads to induction of Nrf2/HO-1 antioxidant response and suppression of NF-κB-dependent processes in tumor cells.

Potensi ekstrak maggot lalat tentara hitam Hermetia illucens (Linnaeus) dalam regulasi mekanisme antioksidan selular dan antiradang: Kajian in silico

Potensi larva (maggot) lalat tentara hitam (black soldier fly/BSF, Hermetia illucens (Linnaeus)) sebagai sumber biofarmaka khususnya antioksidan dan atau antiinflamasi belum diteliti lebih lanjut. Penelitian ini bertujuan mengidentifikasi senyawa dalam ekstrak maggot BSF yang berpotensi mengaktifkan mekanisme persinyalan antioksidan. Maggot BSF yang telah diberi pakan limbah pertanian diekstrak dengan metode maserasi menggunakan pelarut air, metanol, dan aseton. Analisis dengan liquid chromatography-mass spectrometry (LC-MS/MS) terdeteksi 40 senyawa kimia, yaitu 15 dari ekstrak air, 13 dari ekstrak metanol, dan 12 dari ekstrak aseton. Sebagian besar (90%) dari senyawa tersebut memiliki skor bioavailabilitas baik (= 0,55 atau lebih) dengan toksisitas relatif rendah (500 mg/Kg<LD50<5000 mg/Kg BB). Penambatan molekuler memprediksi 26 senyawa bioaktif berpotensi mengaktifkan mekanisme antioksidan di dalam sel via faktor transkripsi NRF2, lebih baik daripada aktivator NRF2 komersil. Senyawa terbaik adalah senyawa larut air dengan PubChem CID: 73775828. Senyawa ini mengikat protein Keap-1 (PDB ID: 6FFM) yang menghambat persinyalan NRF2 dengan energi bebas Gibbs (ΔG) = -6,08 Kkal/mol dan konstanta disosiasi (Kd) = 3,58 × 10-5µM. Adapun penghambatan peradangan via NF-kappa B terbaik ditunjukkan oleh senyawa larut air verpacamide A yang mengikat enzim inhibitor NF-kappa B kinase (IKK2) (PDB ID: 4KIK) dengan ΔG = -5,024 kkal/mol; Kd = 0,207 × 103 µM. Potensi ini lebih baik dari yang ditunjukkan oleh aspirin. Dengan demikian, ekstrak maggot BSF merupakan sumber biofarmaka yang berpotensi mengaktifkan persinyalan antioksidan selular dan menghambat terjadinya inflamasi.

Boosting NAD: An opportunity for metabolic reprogramming of Th17 cells in psoriatic disease

Metabolic reprogramming of CD4 Tcells has become an opportunity for adjunctive therapies. Here, Han etal. show that boosting NAD+ blunts systemic Th17 responses and increases antioxidant pathways through arginine and fumarate-mediated activation of NRF2 transcription factor.

NRF2 transcriptionally regulates Caspase-11 expression to activate HMGB1 release by Autophagy-deficient hepatocytes

Injury or stress can induce intracellular translocation and release of nuclear HMGB1, a DAMP molecule known to participate in inflammation and other pathological processes. Active release of HMGB1 from stimulated macrophages can be mediated by inflammasomes, which cleave Gasdermin D to form pores on cytoplasmic membranes. We previously had shown that active release of HMGB1 from autophagy deficient hepatocytes also depended on the inflammasome but how the inflammasome was activated was not known. Here we report that persistent activation of transcription factor NRF2 under the autophagy deficient condition led to transcriptional upregulation of Caspase-11 expression, which could then activate the CASPASE-1inflammasome. Using chromatin immunoprecipitation (CHIP) and luciferase-based reporter assays, we show that NRF2 directly binds to the Caspase-11 promoter and transcriptionally increase the expression of Caspase-11. Genetic deletion of Caspase-11 in autophagy-deficient livers represses the release of HMGB1 and its pathological consequence, ductular cell proliferation. Consistently, deletion of NLRP3, which can activate CASPASE-1 mediated inflammasomes under other types of signals, did not prevent HMGB1 release and ductular cell proliferation in autophagy deficient livers. Surprisingly, while cleavage of GASDEMIN D occurred in autophagy-deficient livers its deletion did not prevent the HMGB1 release, suggesting that CASPASE-11-mediated inflammasome activation may also engage in a different mechanism for HMGB1 release by the autophagy deficient hepatocytes. Collectively, this work reveals the novel role of NRF2 in transcriptional upregulation of Caspase-11 and in inflammasome activation to promote active release of HMGB via a non-Gasdermin D mediated avenue.

Bioactive compounds in Layacha brown rice (Oryza sativa L.) improve immune responses in mice via activation of transcription factor Nrf2

Dysregulated or weak immunity is caused by ageing, chemo-radiotherapy, COVID-19, infections, steroids, pollutants and toxins. Bioactive foods are required for boosting immunity. In the present study, eight rice (Oryza sativa L.) varieties were selected from the repository of 23,250 Indian germplasm accessions. The immunomodulatory effects of these rice varieties were assessed in vitro and in vivo. Layacha-rice-methanolic-extract (Larimex) significantly enhanced innate (>20%) and adaptive (>10%) immune responses evinced from higher bacterial phagocytosis by macrophages, increased mitogen-induced T-cell proliferation (11%) and scavenged reactive oxygen species (ROS) (70–80%). Larimex activated transcription factor Nrf2 and its downstream genes NQO1, HO1 and Txnrd1 in immune cells. Larimex significantly improved immune responses (>20%) only in cells from wild type but not Nrf2 knock-out mice indicating its causal role in boosting immunity. Untargeted metabolomics of Layacha rice showed preponderance of metabolic pathways and bioactive compounds, which activate Nrf2 in mammalian cells. Layacha rice can be a suitable food for boosting immunity.

Activation of Nrf-2 Transcription Factor and Caspase Pathway with Royal Jelly Reduces Fluoride Induced Testicular Damage and Infertility in Rats.

This study was carried out to investigate the protective properties of royal jelly on the testicular tissue of rats with testicular damage by giving fluoride. Sperm motility, epididymal sperm density and abnormal sperm ratios were examined and visualized with a light microscope. Expression levels of Caspase-3, Bcl-2, Nrf-2, NF-κB, COX-2, TNF-α and IL1-α proteins in testis tissue were determined by western blot technique. As a result of the study, MDA level, expression level of Bcl-2, NFҡB, COX-2, TNF-α and IL1-α proteins, abnormal sperm rates were found higher in Fluoride-50 and Fluoride100 groups compared to other groups. In addition GSH, Catalase enzyme levels, expression levels of Caspase-3 and Nrf-2 proteins were found to be higher in Fluoride + Royal Jelly groups compared to Fluoride-50 and Fluoride-100 groups. In addition, lower degeneration of testicular tissue was found in the histological evaluation in the Fluoride + Royal Jelly groups compared to the other groups. When the data are evaluated royal jelly provides effective protection against testicular damage. From this point of view, we hope that similar results will be obtained when royal jelly is tested on humans.

Gliadin induced oxidative stress and altered cellular responses in human intestinal cells: An in-vitro study to understand the cross-talk between the transcription factor Nrf-2 and multifunctional APE1 enzyme.

The present study examined the wheat protein gliadin-induced oxidative and nitrosative stress and its downstream responses in human intestinal HCT-116 and HT-29 cells. The beneficial role of dietary phytochemical curcumin and role of multifunctional enzyme Apurinic/aprymidinic endonuclease 1 (APE1) a major player involved in the base excision repair (BER)-pathway in gliadin intolerant intestinal HCT-116 and HT-29 cell lines were evaluated as an in vitro model study. The cultured cells were exposed to gliadin protein, H2 O2 , and curcumin followed by the assessment of oxidative stress and the consequences were measured using spectrophotometric, PCR, flow cytometer, Western blotting, confocal microscopy, and other methods. Results demonstrate that a 3 h pretreatment of curcumin, followed by the treatment of gliadin protein for 24 h time period protected both the HCT-116 and HT-29 cells via: (i) decreasing the ROS/RNS, restoring the mitochondrial transmembrane potential; (ii) re-establishing the cellular antioxidant defense system (superoxide dismutase, catalase, and GSH); (iii) enhancing the functions of APE1 viz. endonuclease activity and redox activation of transcription factor Nrf-2, the later binds with the antioxidant response elements (ARE) and activates downstream targets involved in cell survival. The cross-talk between APE1 and Nrf-2 was also established using immunofluorescence imaging and co-immunoprecipitation assays. In conclusion, gliadin protein induces oxidative/nitrosative stress, mitochondrial dysfunction and it damages cellular biomolecules in the intestinal cells. Hence it can be attributed to the tissue damage and disease pathogenesis in wheat intolerance-associated intestinal diseases. The gliadin-induced stress and its consequences are significantly reduced by the pretreatment of curcumin via BER-pathway and ARE-pathway; which is evident through the interaction between these two essential proteins. Hence suggesting for the intervention of curcumin and other natural dietary phytochemicals-based disease management and treatment of gliadin intolerance associated intestinal diseases like celiac disease.

Age-Related Mitochondrial Impairment and Renal Injury Is Ameliorated by Sulforaphane via Activation of Transcription Factor NRF2.

Age is one of the major risk factors for the development of chronic pathologies, including kidney diseases. Oxidative stress and mitochondrial dysfunction play a pathogenic role in aging kidney disease. Transcription factor NRF2, a master regulator of redox homeostasis, is altered during aging, but the exact implications of altered NRF2 signaling on age-related renal mitochondrial impairment are not yet clear. Herein, we investigated the role of sulforaphane, a well-known NRF2 activator, on age-related mitochondrial and kidney dysfunction. Young (2–4 month) and aged (20–24 month) male Fischer 344 rats were treated with sulforaphane (15 mg/kg body wt/day) in drinking water for four weeks. We observed significant impairment in renal cortical mitochondrial function along with perturbed redox homeostasis, decreased kidney function and marked impairment in NRF2 signaling in aged Fischer 344 rats. Sulforaphane significantly improved mitochondrial function and ameliorated kidney injury by increasing cortical NRF2 expression and activity and decreasing protein expression of KEAP1, an NRF2 repressor. Sulforaphane treatment did not affect the renal NRF2 expression or activity and mitochondrial function in young rats. Taken together, our results provide novel insights into the protective role of the NRF2 pathway in kidneys during aging and highlight the therapeutic potential of sulforaphane in mitigating kidney dysfunction in elders.

Early Growth Response 1 Suppresses Macrophage Phagocytosis by Inhibiting NRF2 Activation Through Upregulation of Autophagy During Pseudomonas aeruginosa Infection.

Pseudomonas aeruginosa is an opportunistic pathogen that causes life-threatening infections in cystic fibrosis patients and immunocompromised individuals. A tightly regulated immune response possessed by healthy individuals can effectively control P. aeruginosa infections, whereas the patients with dysregulated immune response are susceptible to this bacterial pathogen. Early growth response 1 (Egr-1) is a zinc-finger transcription factor involved in regulation of various cellular functions, including immune responses. We previously identified that Egr-1 was deleterious to host in a mouse model of acute P. aeruginosa pneumonia by promoting systemic inflammation and impairing bacterial clearance in lung, which associated with reduced phagocytosis and bactericidal ability of leucocytes, including macrophages and neutrophils. However, the molecular mechanisms underlying the Egr-1-suppressed phagocytosis of P. aeruginosa are incompletely understood. Herein, we investigated whether the Egr-1-regulated autophagy play a role in macrophage phagocytosis during P. aeruginosa infection by overexpression or knockdown of Egr-1. We found that overexpression of Egr-1 inhibited the phagocytic activity of macrophages, and the autophagy activator rapamycin and inhibitor chloroquine could reverse the effects of Egr-1 knockdown and Egr-1 overexpression on phagocytosis of P. aeruginosa, respectively. Furthermore, the Egr-1-overexpressing macrophages displayed upregulated expression of autophagy-related proteins LC3A, LC3B and Atg5, and decreased levels of p62 in macrophages. Further studies revealed that the macrophages with Egr-1 knockdown displayed enhanced activation of transcription factor NRF2 and expression of scavenger receptors MACRO and MSR1. Altogether, these findings suggest that Egr-1 suppresses the phagocytosis of P. aeruginosa by macrophages through upregulation of autophagy and inhibition of NRF2 signaling.

Lichen-Derived Depsides and Depsidones Modulate the Nrf2, NF-κB and STAT3 Signaling Pathways in Colorectal Cancer Cells.

The study aimed to evaluate the possible modulation of Nrf2, NF-ĸB and STAT3 signaling pathways in the colorectal cancer (CRC) cells line DLD-1 and HCT116 by secondary metabolites of lichens. An attempt was made to indicate the most promising targets in these signaling pathways. Attention was also paid to the effects of the compounds tested on CRC cells using anakoinosis—that is, simultaneous analysis of several signaling pathways. The effects of the tested natural compounds on the activity of selected transcriptional factors related to CRC were analyzed by Western blot and RT-PCR assays. The highest activity against CRC cells was shown by physodic and salazinic acids from the studied secondary metabolites of lichens. As a result, an increase in the activation of transcription factor Nrf2 and the expression of its selected target genes was observed. Physodic and salazinic acids induced the opposite effect in relation to the NF-κB and STAT3 pathways. These results confirmed our earlier observations that lichen-derived compounds have the ability to modulate signaling pathway networks. While caperatic acid affected Wnt/β-catenin to the most extent, salazinic acid was the most potent modulator of Nrf2, NF-κB and STAT3 pathways. Physodic acid seemed to affect all the investigated pathways.

SARS-CoV2 infection impairs the metabolism and redox function of cellular glutathione

Viral infections sustain their replication cycle promoting a pro-oxidant environment in the host cell. In this context, specific alterations of the levels and homeostatic function of the tripeptide glutathione have been reported to play a causal role in the pro-oxidant and cytopathic effects (CPE) of the virus. In this study, these aspects were investigated for the first time in SARS-CoV2-infected Vero E6 cells, a reliable and well-characterized in vitro model of this infection. SARS-CoV2 markedly decreased the levels of cellular thiols, essentially lowering the reduced form of glutathione (GSH). Such an important defect occurred early in the CPE process (in the first 24 hpi). Thiol analysis in N-acetyl-Cys (NAC)-treated cells and membrane transporter expression data demonstrated that both a lowered uptake of the GSH biosynthesis precursor Cys and an increased efflux of cellular thiols, could play a role in this context. Increased levels of oxidized glutathione (GSSG) and protein glutathionylation were also observed along with upregulation of the ER stress marker PERK. The antiviral drugs Remdesivir (Rem) and Nelfinavir (Nel) influenced these changes at different levels, essentially confirming the importance or blocking viral replication to prevent GSH depletion in the host cell. Accordingly, Nel, the most potent antiviral in our in vitro study, produced a timely activation of Nrf2 transcription factor and a GSH enhancing response that synergized with NAC to restore GSH levels in the infected cells. Despite poor in vitro antiviral potency and GSH enhancing function, Rem treatment was found to prevent the SARS-CoV2-induced glutathionylation of cellular proteins. In conclusion, SARS-CoV2 infection impairs the metabolism of cellular glutathione. NAC and the antiviral Nel can prevent such defect in vitro.

338-OR: Reversal of Insulin Resistance by Resveratrol and Hesperetin Combination in Overweight and Obese Subjects Correlates with Decrease in Expression of Thioredoxin Interacting Protein

Trans-Resveratrol and hesperetin combination (tRES-HESP) in randomized, double-blind, placebo-controlled crossover study in overweight and obese subjects corrected insulin resistance; healthy aging through functional food study (HATFF, Clinicaltrials.gov identifier NCT02095873). tRES-HESP is an optimized supplement for induction of expression of glyoxalase 1 (Glo1) via activation of transcription factor Nrf2. Increased Glo1 expression decreases reactive metabolite, methylglyoxal (MG), contributing to insulin resistance through glycation-linked unfolded protein formation and activation of the unfolded protein response (UPR). Herein, we report further analysis of study variables and follow-up reverse translational studies. With tRES-HESP treatment, plasma MG correlated negatively with peripheral blood mononuclear cell (PBMC) quinone reductase activity - a marker of Nrf2 activation (r = - 0.68, P<0.01). For change from baseline of PBMC gene expression with tRES-HESP treatment (assessed by the Nanostring method), change in area-under-the-curve plasma glucose (ΔAUGg) during oral glucose tolerance tests correlated negatively with change in Glo1 expression (r = - 0.56, P<0.05) and correlated positively with change in expression of thioredoxin interacting protein (TXNIP) (r = 0.59, P<0.05). In reverse translational studies, we found tRES-HESP decreased TXNIP expression by 39 ± 1% (P<0.001) in human hepatocyte-like HepG2 cells and 14 ± 3% in BJ fibroblasts in vitro (P<0.01). tRES-HESP may decrease TXNIP expression by decreasing the MG-driven UPR and by direct Nrf2-driven down regulation. TXNIP is a mediator of insulin resistance in liver and skeletal muscle and impaired pancreatic beta-cell insulin secretion. tRES-HESP is suitable for further evaluation for prevention and treatment of type 2 diabetes where decreased TXNIP may contribute to the therapeutic response. Disclosure M. Xue: None. M. Weickert: None. N. Rabbani: None. P. Thornalley: None. Funding Qatar Foundation; Qatar University

KEAP1 deficiency drives glucose dependency and sensitizes lung cancer cells and tumors to GLUT inhibition

SummaryMetabolic reprogramming in cancer cells can create metabolic liabilities. KEAP1-mutant lung cancer is refractory to most current therapies. Here we show that KEAP1 deficiency promotes glucose dependency in lung cancer cells, and KEAP1-mutant/deficient lung cancer cells are more vulnerable to glucose deprivation than their WT counterparts. Mechanistically, KEAP1 inactivation in lung cancer cells induces constitutive activation of NRF2 transcription factor and aberrant expression of NRF2 target cystine transporter SLC7A11; under glucose limitation, high cystine uptake in KEAP1-inactivated lung cancer cells stimulates toxic intracellular disulfide buildup, NADPH depletion, and cell death, which can be rescued by genetic ablation of NRF2-SLC7A11 axis or treatments inhibiting disulfide accumulation. Finally, we show that KEAP1-inactivated lung cancer cells or xenograft tumors are sensitive to glucose transporter inhibitor. Together, our results reveal that KEAP1 deficiency induces glucose dependency in lung cancer cells and uncover a therapeutically relevant metabolic liability.

A novel NRF2-βTrCP Protein-Protein Interaction (PPI) inhibitor suppresses lipopolysaccharide-mediated inflammation through the activation of transcription factor NRF2.

A novel NRF2-βTrCP Protein-Protein Interaction (PPI) inhibitor suppresses lipopolysaccharide-mediated inflammation through the activation of transcription factor NRF2.

Cancer cells escape autophagy inhibition via NRF2-induced macropinocytosis.

Many cancers, including pancreatic ductal adenocarcinoma (PDAC), depend on autophagy-mediated scavenging and recycling of intracellular macromolecules, suggesting that autophagy blockade should cause tumor starvation and regression. However, until now autophagy-inhibiting monotherapies have not demonstrated potent anti-cancer activity. We now show that autophagy blockade prompts established PDAC to upregulate and utilize an alternative nutrient procurement pathway: macropinocytosis (MP) that allows tumor cells to extract nutrients from extracellular sources and use them for energy generation. The autophagy to MP switch, which may be evolutionarily conserved and not cancer cell restricted, depends on activation of transcription factor NRF2 by the autophagy adaptor p62/SQSTM1. NRF2 activation by oncogenic mutations, hypoxia, and oxidative stress also results in MP upregulation. Inhibition of MP in autophagy-compromised PDAC elicits dramatic metabolic decline and regression of transplanted and autochthonous tumors, suggesting the therapeutic promise of combining autophagy and MP inhibitors in the clinic.

Keap1 Deficiency Drives Glucose Dependency and Sensitizes Lung Cancer Cells and Tumors to Glut Inhibition

Metabolic reprogramming in cancer cells can create metabolic liabilities which could be exploited therapeutically. Tumor suppressor KEAP1 is frequently mutated in lung cancer, and KEAP1-mutant lung cancers are refractory to most current therapies. Here we show that KEAP1 deficiency promotes glucose dependency in lung cancer cells, and KEAP1-mutant or -deficient lung cancer cells are more vulnerable to glucose deprivation than KEAP1-proficient lung cancer cells. Mechanistically, KEAP1 inactivation in lung cancer cells leads to constitutive activation of NRF2 transcription factor and aberrant expression of NRF2 target cystine transporter SLC7A11; under glucose limiting conditions, high cystine uptake in KEAP1-inactivated lung cancer cells results in toxic buildup of intracellular disulfide molecules, NADPH depletion, and subsequent cell death, which can be rescued by either genetic ablation of the NRF2-SLC7A11 signaling axis or treatments that prevent disulfide accumulation. Finally, we show that KEAP1-inactivated lung cancer cells or xenograft tumors are sensitive to glucose transporter (GLUT) inhibitor KL-11743. Together, our results reveal that KEAP1 deficiency induces glucose dependency in lung cancercells and uncover a metabolic liability that can be therapeutically targeted in KEAP1-mutant lung cancer.

Application of the in vivo oxidative stress reporter Hmox1 as mechanistic biomarker of arsenic toxicity

Inorganic arsenic (iAs) is a naturally occurring metalloid present in drinking water and polluted air exposing millions of people globally. Epidemiological studies have linked iAs exposure to the development of numerous diseases including cognitive impairment, cardiovascular failure and cancer. Despite intense research, an effective therapy for chronic arsenicosis has yet to be developed. Laboratory studies have been of great benefit in establishing the pathways involved in iAs toxicity and providing insights into its mechanism of action. However, the in vivo analysis of arsenic toxicity mechanisms has been difficult by the lack of reliable in vivo biomarkers of iAs’s effects. To address this issue we have applied the use of our recently developed stress reporter models to study iAs toxicity. The reporter mice Hmox1 (oxidative stress/inflammation; HOTT) and p21 (DNA damage) were exposed to iAs at acute and chronic, environmentally relevant, doses. We observed induction of the oxidative stress reporters in several cell types and tissues, which was largely dependent on the activation of transcription factor NRF2. We propose that our HOTT reporter model can be used as a surrogate biomarker of iAs-induced oxidative stress, and it constitutes a first-in-class platform to develop treatments aimed to counteract the role of oxidative stress in arsenicosis. Indeed, in a proof of concept experiment, the HOTT reporter mice were able to predict the therapeutic utility of the antioxidant N -acetyl cysteine in the prevention of iAs associated toxicity. • Arsenic induces tissue specific expression of a novel in vivo Hmox-1 reporter. • Expression of NRF2 is necessary for the arsenic induction of Hmox1 in vivo. • The Hmox1 biomarker can predict the utility of therapeutic approaches in arsenicosis.

Activation of transcription factor Nrf2 to counteract mitochondrial dysfunction in Parkinson's disease.

Parkinson's disease (PD) is a progressive neurodegenerative disorder, for which no disease-modifying therapies are available to date. Although understanding of the precise aetiology of PD is incomplete, it is clear that age, genetic predispositionand environmental stressors increase the risk. At the cellular level, oxidative stress, chronic neuroinflammation, mitochondrial dysfunctionand aberrant protein aggregation have been implicated as contributing factors. These detrimental processes are counteracted by elaborate networks of cellular defence mechanisms, one of which is orchestrated by transcription factor nuclear factor-erythroid 2 p45-related factor 2 (Nrf2; gene name NFE2L2). A wealth of preclinical evidence suggests that Nrf2 activation is beneficial in cellular and animal models of PD. In this review, we summarise the current understanding of mitochondrial dysfunction in PD, the role of Nrf2 in mitochondrial functionand explore the potential of Nrf2 as a therapeutic target for mitochondrial dysfunction in PD.

Activation of Transcription Factor Nrf2 Ameliorates Age‐Associated Decline in Kidney Function

Aging has a strong association with the development of kidney disease. About one in four women and one in five men, aged 65 years and above, have chronic kidney disease (CKD). Studies indicate compromised mitochondrial function in aging kidneys. However, the mechanisms of the decreased mitochondrial function in aging is unclear. The present study aims to investigate the mechanisms relating to the mitochondrial dysfunction in aging. The mechanisms thus explored will help us identify novel therapeutic targets to prevent or reverse kidney damage in elder individuals. Nuclear transcription factor Nrf2 is a cytosolic protein which when activated will translocate to the nucleus. After being translocated to the nucleus, it regulates the expression of genes involved in antioxidant and detoxification mechanisms. It binds to Antioxidant Response Element (ARE) on the gene promoters and increases the expression of genes that regulate the function of cells. We previously showed that Nrf2, was decreased in the kidneys of aged rats. Additionally, we also found a decrease in mitochondrial activity and kidney function. Therefore, we hypothesized that Nrf2 regulates kidney function via improving mitochondrial function during aging. We tested this hypothesis, by using Fischer344 rats, animal model of aging, and human kidney cells (HK2) in culture. Aged male Fischer 344 (F344) rats (20–24 months old) were divided into two groups. One group was treated with Nrf2 activator, sulforaphane (SF) [15mg/kg/day in drinking water for four weeks] and the other group (Control) was given drinking water alone. Nrf2 activation had significantly reduced the oxidative stress marker 8‐isoprostane levels in urine and increased urinary antioxidant capacity in the aged rats compared to their controls. The increased levels of protein in urine and plasma creatinine in aged animals were also reduced by sulforaphane treatment. Human kidney cells (HK2) were treated with sulforaphane (SF) at a dose of 20uM in the presence and absence of H2O2. H2O2 treatment significantly reduced Nrf2 expression which was reversed by SF treatment. Also, the mitochondrial membrane potential improved in H2O2+SF treated cells as compared to H2O2 treated cells. In conclusion, our results suggest that Nrf2 activation plays a key role in improving kidney function in aged rats.Support or Funding InformationNIH Aging grant: AG057024‐01A1

Retraction notice: Activation of transcription factor Nrf2 by hepatitis C virus induces the cell-survival pathway.

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