Nrf2 Activator Dimethyl Fumarate Research Articles

Nrf2 activation rescues stress-induced depression-like behaviour and inflammatory responses in male but not female rats

BackgroundMajor depressive disorder (MDD) is a recurring affective disorder that is two times more prevalent in females than males. Evidence supports immune system dysfunction as a major contributing factor to MDD, notably in a sexually dimorphic manner. Nuclear factor erythroid 2-related factor 2 (Nrf2), a regulator of antioxidant signalling during inflammation, is dysregulated in many chronic inflammatory disorders; however, its role in depression and the associated sex differences have yet to be explored. Here, we investigated the sex-specific antidepressant and cognitive effects of the potent Nrf2 activator dimethyl fumarate (DMF), as well as the associated gene expression profiles.MethodsMale and female rats were treated with vehicle or DMF (25 mg/kg) whilst subjected to 8 weeks of chronic unpredictable stress. The effect of DMF treatment on stress-induced depression- and anxiety-like behaviours, as well as deficits in recognition and spatial learning and memory were then assessed. Sex differences in hippocampal (HIP) gene expression responses were also evaluated.ResultsDMF treatment during stress exposure had antidepressant effects in male but not female rats, with no anxiolytic effects in either sex. Recognition learning and memory and spatial learning and memory were impaired in chronically stressed males and females, respectively, and DMF treatment rescued these deficits. Further, chronic stress elicited sex-specific alterations in HIP gene expression, many of which were normalized in animals treated with DMF. Of note, most of the differentially expressed genes in males normalized by DMF were related to antioxidant, inflammatory or immune responses.ConclusionsCollectively, these findings may support a greater role of immune processes in males than females in a rodent model of depression. This suggests that pharmacotherapies that target Nrf2 have the potential to be an effective sex-specific treatment for depression.

Hydroxycitric acid prevents hyperoxaluric-induced nephrolithiasis and oxidative stress via activation of the Nrf2/Keap1 signaling pathway

ABSTRACT Nephrolithiasis is a common and frequently-occurring disease in the urinary system with high recurrence. The present study aimed to explore the protective effect and underlying mechanism of hydroxycitric acid (HCA) in hyperoxaluria-induced nephrolithiasis in vitro and in vivo. Crystal deposition and pathophysiological injury in rat models of glyoxylate-induced nephrolithiasis were examined using H&E staining. Cell models of nephrolithiasis were established by oxalate-treated renal tubular epithelial cells. The levels of oxidative stress indexes were determined by ELISA kits. Cell proliferation in vivo and in vitro was evaluated using a cell counting kit-8 (CCK-8) assay and Ki-67 cell proliferation detection kit. Cell apoptosis was measured by flow cytometry and TUNEL staining. The protein levels were examined by western blotting. Our results showed that HCA administration significantly reduced crystal deposition and kidney injury induced by glyoxylate. HCA also alleviated oxidative stress via upregulating the antioxidant enzyme activities of superoxide dismutase (SOD) and catalase (CAT) and reducing the malondialdehyde (MDA) content. Moreover, HCA treatment promoted cell proliferation and inhibited apoptosis of renal tubular epithelial cells exposed to hyperoxaluria. Of note, Nrf2 activator dimethyl fumarate (DMF) exerted the same beneficial effects as HCA in nephrolithiasis. Mechanistically, HCA prevented crystal deposition and oxidative stress induced by hyperoxaluria through targeting the Nrf2/Keap1 antioxidant defense pathway, while knockdown of Nrf2 significantly abrogated these effects. Taken together, HCA exhibited antioxidation and anti-apoptosis activities in nephrolithiasis induced by hyperoxaluria via activating Nrf2/Keap1 pathway, suggesting that it may be an effective therapeutic agent for the prevention and treatment of nephrolithiasis.

SYVN1 attenuates ferroptosis and alleviates spinal cord ischemia–reperfusion injury in rats by regulating the HMGB1/NRF2/HO-1 axis

BackgroundThe ferroptosis of neurons is an important pathological mechanism of spinal cord ischemia reperfusion injury (SCIRI). Previous studies showed that synoviolin 1 (SYVN1) is a good prognostic marker of neurodegenerative diseases, but its mechanism is still unclear. This study aims to explore the role of SYVN1 in the ferroptosis of neurons and to clarify its internal mechanism. MethodsRat primary spinal cord neurons were treated with oxygen-glucose deprivation (OGD) for 1, 4 or 8 h, and then cell viability, ROS and MDA levels, glutathione peroxidase (GSH-Px) activity, and the expression of ferroptosis-related proteins GPX4, FTH1 and PTGS2 were detected. OGD/R-induced neurons were transfected with pcDNA-SYVN1 or si-HMGB1, and then cell functions were detected. Transmission electron microscope (TEM) was used to detect cell ferroptosis. The interplay between SYVN1 and high mobility group box 1 (HMGB1) was confirmed with Co-immunoprecipitation (Co-IP) assay. The stability of HMGB1 was measured by ubiquitination assay. Also, cells were treated with pcDNA-SYVN1 or together with ubiquitination inhibitor MG132, as well as treated with pcDNA-SYVN1 and pcDNA-HMGB1 or together with NRF2 activator dimethyl fumarate (DMF), and then Western blotting was used to detect the expression of HMGB1, nuclear NRF2 and HO-1 proteins. In addition, SD rats were occluded left common carotid artery and aortic arch to establish a SCIRI rat model. And rats were injected intrathecal with adenovirus-mediated SYVN1 overexpression vector (Ad-SYVN1, 2 μL, virus titer 5 × 1013 transduction unit [TU]/mL) to overexpress SYVN1. The motion function of rats was quantified using the Basso Rat Scale (BMS) for Locomotion. The ferroptosis and the number of neurons in the spinal cord tissue of rats were detected. ResultsSYVN1 overexpression inhibited ferroptosis of SCIRI rats and OGD/R-treated primary spinal cord neurons, and down-regulated the expression of HMGB1. In terms of mechanism, the binding of SYVN1 and HMGB1 promoted the ubiquitination and degradation of HMGB1, and negatively regulated the expression of HMGB1. Moreover, under OGD/R conditions, MG132 treatment or HMGB1 overexpression eliminated the inhibitory effect of SYVN1 overexpression on the ferroptosis of neurons and the activation of the NRF2/HO-1 pathway, and DMF treatment abolished the inhibition of HMGB1 overexpression on the NRF2/HO-1 pathway. Finally, in vivo experiments showed that SYVN1 overexpression could alleviate the spinal cord ischemia–reperfusion injury in rats by down-regulating HMGB1 and promoting the activation of the NRF2/HO-1 pathway. ConclusionSYVN1 regulates ferroptosis through the HMGB1/NRF2/HO-1 axis to prevent spinal cord ischemia–reperfusion injury.

Central nervous system IL-17R expression influences weight gain by altering food-intake and fat-mass accumulation

Abstract Cytokines influence innate behaviors in mice and IL-17a may function within the hypothalamus to reduce food-intake. We examine contributions of nervous system IL-17R expression on mouse feeding behavior following obesogenic diet exposure. We crossed IL-17Ra f/fand Synapsin1-Cre or Na v1.8-Cre mice to generate pan-neuronal (Syn-Cre IL-17Ra f/f) or peripheral neuronal- (Na-v1.8-Cre IL17Ra f/f) IL-17R knockout mice, respectively. Body weights of male and female mice were measured over 10-weeks of 60% high-fat diet (HFD) feeding. 60% HFD fed male Syn-Cre IL-17Ra f/fand IL-17Ra f/fmice underwent metabolic phenotyping and body composition analyses. Syn-Cre IL-17Ra f/fand IL-17Ra f/fmice received CNS penetrant Nrf2 activator Dimethyl-Fumarate (DMF) to assess whether pharmacological inhibition of IL-17a secretion alters HFD induced weight gain. Male and female Syn-Cre IL-17Ra f/fbut not Na-v1.8-Cre IL17Ra f/fmice displayed a 15–20% reduction in bodyweight after 10-weeks of HFD feeding (male p=0.00046, female p=0.0061). DMF treatment did not impact body weight. Syn-Cre IL-17Ra f/ftrended towards a reduction in food-intake and meal numbers when compared to IL-17Ra f/fmice. Syn-Cre IL-17Ra f/fhad a significant reduction in fat mass (total p=0.01, %total p=0.04) and lean mass (total p=0.03 and %total p=0.04). In sum, loss of central but not peripheral nervous system expression of IL-17R robustly and significantly blunts weight gain following chronic exposure to an obesogenic diet. This decrease in body weight was associated with a decrease in total fat mass. Our data suggest that a population of IL-17R expressing neurons within the brain influence food-intake by modulating feeding behaviors associated with meal frequency. NIH funding sources include F31-DK127728 and T32-DK07563

DMF-Activated Nrf2 Ameliorates Palmitic Acid Toxicity While Potentiates Ferroptosis Mediated Cell Death: Protective Role of the NO-Donor S-Nitroso-N-Acetylcysteine

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease that can develop into an aggressive form called nonalcoholic steatohepatitis (NASH), which ultimately progresses to cirrhosis, hepatocellular carcinoma (HCC), and end-stage liver failure. Currently, the deterioration of NAFLD is attributed to specific lipid toxicity which could be due to lipotoxicity and/or ferroptosis. In the current study, we evaluated the involvement of the nuclear factor erythroid 2 (NFE2)-related factor 2 (Nrf-2), which is a main activator of phase II metabolism in the two types of lipid-induced toxicity in hepatocytes, lipotoxicity by saturated fatty acids, and in ferroptosis, and the effect of NO donor treatment. AML12 cells were exposed to 600 μM palmitic acid to induce lipotoxicity or treated with 20 μM erastin or 5 μM RSL3 for ferroptosis. In SFA-lipotoxicity, pretreatment with the Nrf2 activator dimethyl fumarate (DMF) managed to ameliorate the cells and the oxidative stress level while aggravating ferroptosis due to emptying the thiol pool. On the other hand, the nitric oxide (NO)-donor, S-nitroso-N-acetylcysteine (NAC-SNO) proved to be effective in the prevention of hepatocytes ferroptosis.

1,3-Dichloro-2-propanol-Induced Renal Tubular Cell Necroptosis through the ROS/RIPK3/MLKL Pathway.

1,3-Dichloro-2-propanol (1,3-DCP), as a food pollutant, exists in a variety of foods. Studies have shown that it has nephrotoxicity. In the study, we found that 1,3-DCP caused renal injury with necroptosis in C57BL/6J mice. The mechanism of 1,3-DCP-caused nephrotoxicity was further explored in NRK-52E cells in vitro. We found that 1,3-DCP caused cell necroptosis with the increase in lactate dehydrogenase (LDH) levels and the expressions of RIPK3 and MLKL. But pretreatment with a ROS inhibitor N-acetyl-l-cysteine (NAC), a RIPK3 inhibitor GSK'872, or RIPK3 gene silencing alleviated 1,3-DCP-induced cell necroptosis. The data indicated that 1,3-DCP induced necroptosis through the ROS/RIPK3/MLKL pathway in NRK-52E cells. In further mechanistic studies, we explored how 1,3-DCP induced ROS production. We found that 1,3-DCP inhibited the expressions of nuclear and cytoplasmic Nrf2. But pretreatment with an Nrf2 activator dimethyl fumarate (DMF) up-regulated the expressions of nuclear and cytoplasmic Nrf2 and down-regulated ROS levels and RIPK3 and MLKL expressions. We also examined the effects of mitophagy on 1,3-DCP-induced ROS. The data manifested that 1,3-DCP suppressed mitophagy in NRK-52E cells by decreasing LC3-II, Pink1, and Parkin levels, increasing p62 levels, and decreasing colocalization of LC3 and Mito-Tracker Red. Pretreatment with an autophagy activator rapamycin (Rapa) decreased 1,3-DCP-induced ROS. Taken together, our data identified that 1,3-DCP caused renal necroptosis through the ROS/RIPK3/MLKL pathway.

ERK1 loss accelerates the progression of osteoarthritis in aged mice via NRF2/BACH1 signaling

Osteoarthritis (OA) is now a common degenerative joint related disease. However, the clinical efficacy of drugs associated with cartilage regeneration remains limited. In our study, we firstly explored the role of ERK1 in the progression of OA. We clarified that ERK1-deficient mice were susceptible to age-related OA. The higher OARSI scores and more severe cartilage degeneration was observed in the ERK1-deficient mice. ERK1 deficiency decreased the nuclear transportation of Nrf2 in the chondrocytes and accelerated chondrocyte aging in vitro. Moreover, chondrocytes with ERK1 deficiency elevated the nuclear expression of BACH1, resulting in lowered expression of antioxidant enzymes in ERK1-deficient chondrocytes. The Nrf2 activator dimethyl fumarate (DMF) was used. Our experiments demonstrated the protective function of DMF against OA in ERK1 knockout mice. Above all, we confirmed the effects of ERK1 on the progression of OA and clarified the mechanisms underlying these effects. DMF might has significant use in the development of novel drugs for the therapy of OA in the future.

NRF2 Activation Ameliorates Oxidative Stress and Improves Mitochondrial Function and Synaptic Plasticity, and in A53T α-Synuclein Hippocampal Neurons.

In Parkinson’s disease (PD), brain oxidative stress and mitochondrial dysfunction contribute to neuronal loss as well as motor and cognitive deficits. The transcription factor NRF2 has emerged as a promising therapeutic target in PD because it sits at the intersection of antioxidant and mitochondrial pathways. Here, we investigate the effects of modulating NRF2 activity in neurons isolated from a A53T α-synuclein (A53TSyn) mouse model of synucleinopathy. Embryonic hippocampal neurons were isolated from A53TSyn mice and their wild type (WT) littermates. Neurons were treated with either the NRF2 activator dimethyl fumarate (DMF) or the NRF2 inhibitor ML385. Reactive oxygen species (ROS), dendritic arborization and dendritic spine density were quantified. Mitochondrial bioenergetics were also profiled in these neurons. A53TSyn neurons had increased ROS and reduced basal and maximal mitochondrial respiration relative to WT neurons. A53TSyn neurons also displayed decreased dendritic arborization and reduced spine density. Treatment with DMF reduced ROS levels and improved both mitochondrial function and arborization, while inhibition of NRF2 with ML385 exacerbated these endpoints. Modulation of NRF2 activity had a significant effect on mitochondrial function, oxidative stress, and synaptic plasticity in A53TSyn neurons. These data suggest that NRF2 may be a viable target for therapeutic interventions in PD.

Noise-Induced Vascular Dysfunction, Oxidative Stress, and Inflammation Are Improved by Pharmacological Modulation of the NRF2/HO-1 Axis.

Vascular oxidative stress, inflammation, and subsequent endothelial dysfunction are consequences of traditional cardiovascular risk factors, all of which contribute to cardiovascular disease. Environmental stressors, such as traffic noise and air pollution, may also facilitate the development and progression of cardiovascular and metabolic diseases. In our previous studies, we investigated the influence of aircraft noise exposure on molecular mechanisms, identifying oxidative stress and inflammation as central players in mediating vascular function. The present study investigates the role of heme oxygenase-1 (HO-1) as an antioxidant response preventing vascular consequences following exposure to aircraft noise. C57BL/6J mice were treated with the HO-1 inducer hemin (25 mg/kg i.p.) or the NRF2 activator dimethyl fumarate (DMF, 20 mg/kg p.o.). During therapy, the animals were exposed to noise at a maximum sound pressure level of 85 dB(A) and a mean sound pressure level of 72 dB(A). Our data showed a marked protective effect of both treatments on animals exposed to noise for 4 days by normalization of arterial hypertension and vascular dysfunction in the noise-exposed groups. We observed a partial normalization of noise-triggered oxidative stress and inflammation by hemin and DMF therapy, which was associated with HO-1 induction. The present study identifies possible new targets for the mitigation of the adverse health effects caused by environmental noise exposure. Since natural dietary constituents can achieve HO-1 and NRF2 induction, these pathways represent promising targets for preventive measures.

Nrf2 protects against seawater drowning-induced acute lung injury via inhibiting ferroptosis

BackgroundFerroptosis is a new type of nonapoptotic cell death model that was closely related to reactive oxygen species (ROS) accumulation. Seawater drowning-induced acute lung injury (ALI) which is caused by severe oxidative stress injury, has been a major cause of accidental death worldwide. The latest evidences indicate nuclear factor (erythroid-derived 2)-like 2 (Nrf2) suppress ferroptosis and maintain cellular redox balance. Here, we test the hypothesis that activation of Nrf2 pathway attenuates seawater drowning-induced ALI via inhibiting ferroptosis.Methodswe performed studies using Nrf2-specific agonist (dimethyl fumarate), Nrf2 inhibitor (ML385), Nrf2-knockout mice and ferroptosis inhibitor (Ferrostatin-1) to investigate the potential roles of Nrf2 on seawater drowning-induced ALI and the underlying mechanisms.ResultsOur data shows that Nrf2 activator dimethyl fumarate could increase cell viability, reduced the levels of intracellular ROS and lipid ROS, prevented glutathione depletion and lipid peroxide accumulation, increased FTH1 and GPX4 mRNA expression, and maintained mitochondrial membrane potential in MLE-12 cells. However, ML385 promoted cell death and lipid ROS production in MLE-12 cells. Furthermore, the lung injury became more aggravated in the Nrf2-knockout mice than that in WT mice after seawater drowning.ConclusionsThese results suggested that Nrf2 can inhibit ferroptosis and therefore alleviate ALI induced by seawater drowning. The effectiveness of ferroptosis inhibition by Nrf2 provides a novel therapeutic target for seawater drowning-induced ALI.

Noise‐induced vascular dysfunction, oxidative stress and inflammationare improved by pharmacological heme oxygenase‐1 induction

Endothelial dysfunction, vascular oxidative stress and inflammation are consequences of traditional cardiovascular risk factors and triggers of cardiovascular disease. However, emerging environmental stressors such as traffic noise exposure may facilitate the development of cardiovascular and metabolic diseases.C57BL/6J mice were exposed to aircraft noise (maximum sound level of 85 dB(A), average sound pressure level of 72 dB(A)) applied for 1, 2 and 4 days caused an increase in systolic blood pressure, stress hormones and induced endothelial dysfunction, oxidative stress and inflammation (Eur Heart J 2017). We also observed reduced vascular NO levels due to eNOS uncoupling and increased levels of nitrotyrosine, interleukin‐6, NADPH oxidase isoform Nox2 and endothelin‐1 in the mice exposed to aircraft noise. More recently, we have shown that aircraft noise induces also cerebral oxidative stress and a neuroinflammatory phenotype that is up‐stream of the observed adverse cardiovascular effects, all of which was normalized by genetic deletion of NADPH oxidase isoform Nox2 (Eur Heart J 2018).The role of heme oxygenase‐1 (HO‐1) as an antioxidant response is currently being investigated. C57BL/6J mice were treated with the HO‐1 activator hemin (25 mg/kg i.p.). Our preliminary data show a protective effect of hemin infusion on aircraft noise exposure (4 days) induced increase of systolic blood pressure and vascular dysfunction. There was also a trend of normalization of noise‐triggered oxidative stress ny hemin infusion. Within the ongoing studies, we will address the impact of HO‐1 induction in noise‐exposed mice on expression of genes and proteins involved in pathways of oxidative stress and systemic inflammation. In a later stage of the study, we will also test whether genetic deficiency of HO‐1 (HO‐1+/− mice) aggravates and the Nrf2 activator dimethyl fumarate (DMF) ameliorates noise‐triggered cardiovascular complications. The present study aims at identifying new targets for mitigation strategies against adverse health effects of environmental noise exposure of the general population. Since HO‐1 and Nrf2 induction can be achieved by natural dietary constituents, these pathways represent promising targets for preventive measures.Support or Funding InformationOur experimental studies on noise effects in mice were supported by vascular biology research grants from the Else‐Kröner‐Fresenius Foundation for “Noise and arterial hypertension” (2017_A106) and the Boehringer Ingelheim Foundation for the collaborative research group „Novel and neglected cardiovascular risk factors: molecular mechanisms and therapeutic implications”.

Electrophiles Against (Skin) Diseases: More Than Nrf2.

The skin represents an indispensable barrier between the organism and the environment and is the first line of defense against exogenous insults. The transcription factor NRF2 is a central regulator of cytoprotection and stress resistance. NRF2 is activated in response to oxidative stress by reactive oxygen species (ROS) and electrophiles. These electrophiles oxidize specific cysteine residues of the NRF2 inhibitor KEAP1, leading to KEAP1 inactivation and, subsequently, NRF2 activation. As oxidative stress is associated with inflammation, the NRF2 pathway plays important roles in the pathogenesis of common inflammatory diseases and cancer in many tissues and organs, including the skin. The electrophile and NRF2 activator dimethyl fumarate (DMF) is an established and efficient drug for patients suffering from the common inflammatory skin disease psoriasis and the neuro-inflammatory disease multiple sclerosis (MS). In this review, we discuss possible molecular mechanisms underlying the therapeutic activity of DMF and other NRF2 activators. Recent evidence suggests that electrophiles not only activate NRF2, but also target other inflammation-associated pathways including the transcription factor NF-κB and the multi-protein complexes termed inflammasomes. Inflammasomes are central regulators of inflammation and are involved in many inflammatory conditions. Most importantly, the NRF2 and inflammasome pathways are connected at different levels, mainly antagonistically.

Diethylnitrosamine and thioacetamide-induced hepatic damage and early carcinogenesis in rats: Role of Nrf2 activator dimethyl fumarate and NLRP3 inhibitor glibenclamide

Two-stage rat hepatocarcinogenesis model was used to induce early carcinogenesis in which thioacetamide (TAA) promotes diethylnitrosamine (DEN) initiated carcinogenesis. Dimethyl fumarate (DMF) used to treat multiple sclerosis, activates the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant responsive element (ARE) pathway during oxidative stress, and maintains antioxidant levels. Glibenclamide (GLB), a sulphonylurea drug used to treat type II diabetes, possesses anti-inflammatory properties and inhibits NLRP3 inflammasomes. The present study was designed to investigate the concurrent intervention of DMF and GLB on DEN + TAA-induced early hepatic carcinogenesis. DMF and GLB treatment improved DEN + TAA-induced decrease in body weight, increase in liver weight and plasma transaminases, histopathological alterations, DNA damage, and apoptosis. DMF and GLB intervention significantly ameliorated the DEN + TAA-induced alterations in the antioxidant (Nrf2, HO-1, SOD-1, catalase), inflammatory (NF-κB, NLRP3, ASC, caspase-1), fibrogenic (TGF-β1, collagen) and regenerative proliferative stress (GST-p, HGF, c-MET, TGFα, EGF, AFP) markers. The present results indicate that Nrf2/ARE activation and NLRP3 inhibition might be a rational approach to attenuate oxidative stress and chronic inflammation associated progression of hepatocarcinogenesis.

Nrf2 Suppression Delays Diabetic Wound Healing Through Sustained Oxidative Stress and Inflammation.

Impaired wound healing is one of the major complications of diabetes, involving prolonged inflammation, delayed re-epithelialization, and consistent oxidative stress. The detailed mechanism remains unclear, and there is currently no effective treatment for diabetic wound healing. In this study, we aim to investigate the potential role and effect of nuclear factor erythroid-2–related factor-2 (Nrf2) activation on diabetic wound healing. In vitro experiments in rat macrophages showed that hyperglycemia treatment suppresses Nrf2 activation, resulting in oxidative stress with decreased expression of antioxidant genes, including NAD(P)H:quinone oxidoreductase 1 and heme oxygenase 1, together with increased secretion of proinflammatory cytokines, including interleukin 1β (IL1β), IL6, and monocyte chemoattractant protein-1. Both Nrf2 overexpression and Nrf2 activator dimethyl fumarate (DMF) treatment significantly ameliorated oxidative stress and inflammation. On the other hand, both Nrf2 knockdown or Nrf2 inhibitor ML385 mimicked the effect of diabetes. Further in vivo experiments in rats showed that DMF treatment significantly accelerated wound healing in streptozocin-induced diabetic rats with increased expression of antioxidant enzymes and decreased secretion of proinflammatory cytokines, while Nrf2 inhibitor ML385 mimicked the effect of diabetes. We conclude that Nrf2 activation accelerates impaired wound healing by ameliorating diabetes-mediated oxidative stress and inflammation. This provides a new clinical treatment strategy for diabetic wound healing using Nrf2 activator DMF.

Protection of Male Rat Offspring against Hypertension Programmed by Prenatal Dexamethasone Administration and Postnatal High-Fat Diet with the Nrf2 Activator Dimethyl Fumarate during Pregnancy.

Hypertension can originate from early-life exposure to oxidative stress. As reported, dimethyl fumarate (DMF) activates nuclear factor erythroid-derived 2-related factor 2 (Nrf2) and protects against oxidative stress damage. We examined whether maternal DMF therapy protects adult offspring against hypertension programmed by prenatal dexamethasone (DEX) and postnatal high-fat (HF) diet exposure. We examined male Sprague Dawley rat offspring at 4 months of age from five groups (n = 11–13/group): control, DEX (0.1mg/kg i.p. from gestational day 16 to 22), HF (D12331 diet from weaning to 16 weeks of age), DEX+HF, and DEX+HF+DMF (50mg/kg/day via gastric gavage for 3 weeks during pregnancy). Maternal DMF therapy prevented male offspring against hypertension programmed by combined DEX and HF exposures. The protective effects of maternal DMF include reduced oxidative stress, decreased plasma asymmetric dimethylarginine (ADMA) levels, downregulated the renin-angiotensin system (i.e. Ren, Agt, Ace, and Agtr1a), increased renal protein levels of certain nutrient-sensing signals, and promoted autophagy. In conclusion, maternal Nrf2 activation by DMF protects male adult offspring against hypertension programmed by combined DEX and HF exposures. Our results cast a new light on the therapeutic potential of targeting Nrf2 signaling pathway as reprogramming strategies to prevent programmed hypertension in children exposed to antenatal corticosteroids and postnatally excessive consumption of fat.

Inhibiting inflammation and modulating oxidative stress in oxalate-induced nephrolithiasis with the Nrf2 activator dimethyl fumarate

Hyperoxaluria induces oxidative stress, and inflammation causes renal epithelial cell injury in nephrolithiasis, suggesting that reduced oxalate toxicity may be beneficial. This study aimed to investigate whether nuclear factor (erythroid-derived 2)-like 2 (Nrf2, also called Nfe2l2) induced by dimethyl fumarate (DMF) could protect renal epithelial cells against oxalate-mediated injury both in vivo and in vitro. Glyoxylic acid monohydrate was intraperitoneally injected into Sprague-Dawley rats with or without intragastric administration of DMF. We showed that calcium oxalate crystallisation, accompanied by overexpression of oxidant species and inflammatory cytokines and apoptosis in the rat kidney, was partially reversed by treatment with DMF. Furthermore, oxalate induced a reduction in cell viability, cell damage, oxidant species overexpression, mitochondrial dysfunction, and apoptosis in normal rat kidney epithelial-like (NRK-52E) cells, which were reversed by DMF. Pretreatment of NRK-52E cells with DMF significantly increased Nrf2 levels in the nucleus, with subsequent inhibition of the expression of the nicotinamide adenine dinucleotide phosphate subunits Nox4 and P22, canonical inflammation, and osteogenesis-associated differentiation of target genes in the cytoplasm. This effect was partially inhibited by transfection with Nrf2 siRNA and strengthened by transfection with Kelch-like ECH-associated protein 1 siRNA. These results suggest that DMF exerts beneficial effects in nephrolithiasis by inhibiting inflammation and modulating oxidative stress via regulation of Nrf2.

NRF2 mitigates acute alcohol-induced hepatic and pancreatic injury in mice

Binge alcohol drinking is an important health concern and well-known risk factor for the development of numerous disorders. Oxidative stress plays a critical role in the pathogenesis of acute alcoholism. Nuclear factor erythroid 2 like 2 (NRF2) is a master regulator of cellular adaptive response to oxidative insults. However, the role of NRF2 in acute alcoholism and associated pathologies remains unclear. We found that Nrf2-knockout (Nrf2-KO) mice had exaggerated hypoglycemia and hypothermia and increased mortality compared to wildtype mice after binge ethanol exposure. This phenotype was partially rescued by providing warm environment and/or glucose administration. Acute high dose of alcohol exposure resulted in substantially worsened liver and pancreatic injuries in Nrf2-KO mice. Importantly, deficiency of Nrf2 allowed severe pancreatitis and pancreatic β-cell injury with increased insulin secretion and/or leaking during binge ethanol exposure, which contributed to hypoglycemia. In contrast, a clinically used NRF2 activator dimethyl fumarate (DMF) protected against hypoglycemia and lethality induced by acute ethanol exposure. Furthermore, Nrf2-KO mice likely had defective hepatic acetaldehyde metabolism. Taken together, NRF2 plays an important protective role against acute binge alcohol-induced hepatic and pancreatic damage, which may be partially attributable to its primary regulating role in antioxidant response and impact on ethanol metabolism.

Neuroprotective effect of Nrf2 activator dimethyl fumarate, on the hippocampal neurons in chemical kindling model in rat

BackgroundNuclear factor erythroid-2 related factor 2 (Nrf2) is a transcription factor, which activates the anti-oxidative stress response pathway. In epilepsy, oxidative stress is one of the key factors in the progression of the disease. So, the neuroprotective role of dimethyl fumarate (DMF), a Nrf2 pathway activator was explored in pentylenetetrazole (PTZ) induced kindling model of epilepsy in rats. MethodsMale Wistar rats were subjected to different doses of DMF (15, 30, 60 mg/kg) to evaluate the effect on the PTZ induced kindling in rats. Seizure scoring, the percentage of animals kindled, histopathological analysis of hippocampus and biochemical estimation were done to study the effect of DMF on PTZ induced oxidative stress in rats. Key findingsThe number of kindled animals in the DMF 60 mg/kg treatment group (25%) was less in comparison to corn oil + PTZ control group (62.5%). The histopathological analysis of the hippocampus revealed a significant (p = 0.003) decrease in neuronal damage in DMF 60 mg/kg group as compared to corn oil + PTZ control group. The DMF 60 mg/kg treatment improved the level of antioxidants: glutathione peroxidase (GPx), superoxide dismutase (SOD), reduced glutathione (GSH) and reduced the lipid peroxidation as compared to corn oil + PTZ group. ConclusionsDMF has demonstrated the neuroprotective effect in PTZ induced kindling model of epilepsy. This can prove advantageous in the development of new treatment strategies for epilepsy.

Inhibiting inflammation and modulating oxidative stress in oxalate induced nephrolithiasis with the Nrf2 activator dimethyl fumarate

Inhibiting inflammation and modulating oxidative stress in oxalate induced nephrolithiasis with the Nrf2 activator dimethyl fumarate

Repurposing the NRF2 Activator Dimethyl Fumarate as Therapy Against Synucleinopathy in Parkinson's Disease.

This preclinical study was aimed at determining whether pharmacological targeting of transcription factor NRF2, a master controller of many homeostatic genes, might provide a disease-modifying therapy in the animal model of Parkinson's disease (PD) that best reproduces the main hallmark of this pathology, that is, α-synucleinopathy, and associated events, including nigral dopaminergic cell death, oxidative stress, and neuroinflammation. Pharmacological activation of NRF2 was achieved at the basal ganglia by repurposing dimethyl fumarate (DMF), a drug already in use for the treatment of multiple sclerosis. Daily oral gavage of DMF protected nigral dopaminergic neurons against α-SYN toxicity and decreased astrocytosis and microgliosis after 1, 3, and 8 weeks from stereotaxic delivery to the ventral midbrain of recombinant adeno-associated viral vector expressing human α-synuclein. This protective effect was not observed in Nrf2-knockout mice. In vitro studies indicated that this neuroprotective effect was correlated with altered regulation of autophagy markers SQTSM1/p62 and LC3 in MN9D, BV2, and IMA 2.1 and with a shift in microglial dynamics toward a less pro-inflammatory and a more wound-healing phenotype. In postmortem samples of PD patients, the cytoprotective proteins associated with NRF2 expression, NQO1 and p62, were partly sequestered in Lewy bodies, suggesting impaired neuroprotective capacity of the NRF2 signature. These experiments provide a compelling rationale for targeting NRF2 with DMF as a therapeutic strategy to reinforce endogenous brain defense mechanisms against PD-associated synucleinopathy. DMF is ready for clinical validation in PD. Antioxid. Redox Signal. 25, 61-77.