Augusta University Discovers How Nrf2 Activator Preserves Sight in Retinal Degeneration Model

Augusta University Discovers How Nrf2 Activator Preserves Sight in Retinal Degeneration Model

AUGUSTA, Ga. (Dec. 6, 2017) – In an exciting breakthrough scientists have discovered that a common pain medication often prescribed for chronic pain  can help preserve vision in a model of severe, blinding retinal degeneration.

The vision preservation could activate one of the most powerful antioxidants in the human body known as Nrf2. This targets receptors to protect neurodegenerative diseases.

The drug is known as pentazocine, and is a receptor of sigma 1, a powerful natural antioxidant and Nrf2 activator.

“We are very, very pleased that we can now explore the mechanisms,”, mentioned Dr. Sylvia Smith, chair of the Department of Cellular Biology and Anatomy at the Medical College of Georgia at Augusta University and co-director of the James and Jean Culver Vision Discovery Institute at AU.

A new $1.14 million grant from the National Eye Institute is enabling research to explore the nrf2 protecting ability against sight-degrading conditions like retinitis pigmentosa, macular degeneration and glaucoma.

The protective power of activated Nrf2 through the Sigma 1 receptor (a well-established non-opioid pain receptor) is  an essential means to a healthy retina. Without the sigma 1 receptor, the Müller cells that support our photoreceptor cells are overpowered by oxidative stress (cellular damage) impacting oxygen supply and light to enable healthy vision.

The studies showing Pentazocine activating the sigma 1 receptor have been reported in the 2016  Journal Proceedings of the National Academy of Sciences.

 

How does it work?

The proteins Nrf2 and Keap1 and cul3, congregate quietly in the cell cytoplasm. Excess production of antioxidants by Nrf2 activation moves to the cell proteasome to be eliminated.

But if needed such as in a case of increased oxidative stressas manifest in conditions like retinitis pigmentosa and aging – Nrf2 and Keap1 response activates hundreds of natural antioxidants and cell protection genes.

“It can launch an almost amazing response to stress,” says Smith. “I think it’s arguably the most important antioxidant in cells.”

Dr. Bobby Thomas, neuroscientist in the MCG Department of Pharmacology and Toxicology, is a coinvestigator with Smith on these studies and also exploring the pathway in Parkinson’s disease.

Dr. Smith explains, “Millions of super metabolically active photoreceptor cells in the retina – some 125 million rods and 6 million cones – use a lot of oxygen constantly converting light into images. In the case of retinitis pigmentosa, it’s actually a genetic mutation that kills off the rods but their death creates so much oxidative stress that the cones also are lost in a “bystander” effect.

It’s the cones pentazocine appears to protect, which should enable individuals to maintain functional vision. Interestingly and inexplicably, the high oxidative stress increases the binding of pentazocine to the sigma 1 receptor.”

The studies are being done in mouse cone cells from the retina and the supportive Müller cells. Other collaborators include Dr. Graydon B. Gonsalvez, cell biologist in the MCG Department of Cellular Biology and Anatomy, and Dr. Alan Saul, neuroscientist and electrophysiologist in the MCG Department of Ophthalmology.

For further information contact https://www.augusta.edu/mcg/

1,2

1. Tang C, Li K, Yu Q, Jiang Q, Yao J, Cao C. Activation of Nrf2 by Ginsenoside Rh3 protects retinal pigment epithelium cells and retinal ganglion cells from UV. Free Radic Biol Med. February 2018. [PubMed]
2. Deliyanti D, Alrashdi S, Tan S, et al. Nrf2 Activation Is a Potential Therapeutic Approach to Attenuate Diabetic Retinopathy. Invest Ophthalmol Vis Sci. 2018;59(2):815-825. [PubMed]

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    New Protandim Study – International Formula Impact on Oxidative Stress

    New Protandim Study – International Formula Impact on Oxidative Stress

    LifeVantage Corporation announced a study on Protandim which was presented at the 2014 Experimental Biology Conference held April 26-30, 2014  in San Diego, California.

    Experimental Biology is an annual meeting attended by more than 14,000 scientists. The theme for 2014 was “Transforming the Future through Science.” The  Colorado State University study entitled Oxidative Stress is Decreased with Short-Term Protandim Use. The placebo-controlled double-blind study supplemented overweight/obese adults with ages from 45-69 for 30-days with LifeVantage’s Protandim international formula currently sold in Japan. The results indicated a significant reduction in markers of oxidative stress in subjects receiving this Protandim formulation.

    Dr. Shawn Talbott, LifeVantage Chief Science Officer of LifeVantage commented, “We are pleased to see clinical studies involving our unique products. This research will be added to our large and growing portfolio of scientific studies and builds on the growing collection of evidence supporting Nrf2 activation and oxidative stress reduction associated with Protandim. In addition, this study demonstrates that both of our formulations of Protandim are potent oxidative stress reducers. This allows us to offer people a powerful Nrf2 activator and oxidative stress reduction product in most jurisdictions.”

    Abstracts of the conference can be found at the Journal of the Federation of American Societies for Experimental Biology.Edit Post

    Rebecca Scalzo, Janelle Davis, Joseph Beals, Laurie Biela, Gregory Giordano, Hunter Paris Benjamin Miller, Karyn Hamilton, and Christopher Bell, (2014) Oxidative stress is decreased with short-term Protandim use when piperine is substituted for ashwagandha (LB399) FASEB J April 28:LB399.

    Other Protandim studies can be viewed at Protandim Pubmed Studies

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      Reversal of persistent fibrosis in aging by targeting nox4-Nrf2 redox imbalance – Sciencemag.org

      Reversal of persistent fibrosis in aging by targeting nox4-Nrf2 redox imbalance – Sciencemag.org

      Emphysema and honeycomb fibrosis

      Emphysema and honeycomb fibrosis (Photo credit: Pulmonary Pathology)

      A brand new article in Sciencemag.org presents a study demonstrating how pathological fibrosis increases with age, but how NRF2 activation in mice was able to reverse the damage and repair lung capacity and fibrosis (scar tissue) resolution.

      This is a promising study because the current treatments of pathological  and cystic fibrosis are costly and very time consuming. Persistent fibrosis in lungs of aged mice was caused by the loss of cellular redox balance. The mice in the study with low NRF2 expression had a higher incidence of progressive lung disease. Tissues from human lung samples demonstrated this same Nox4-Nrf2 imbalance.

      The abstract concludes with the following promising statement. “The studies suggest that restoration of Nox4-Nrf2 redox balance in myofibroblasts may be a therapeutic strategy in age-associated fibrotic disorders, potentially able to resolve persistent fibrosis or even reverse its progression.”

       

      Further research on the topic of Nrf2 and Fibrosis:

       

      Chalcone flavokawain A attenuates TGF-β1-induced fibrotic pathology via inhibition of ROS/Smad3 signaling pathways and induction of Nrf2/ARE-mediated antioxidant genes in vascular smooth muscle cells
      Hseu YC, Yang TY, Li ML, Rajendran P, Mathew DC, Tsai CH, Lin RW, Lee CC and Yang HL
      TGF-β1 plays a crucial role in the pathogenesis of vascular fibrotic diseases. Chalcones are reportedly cancer chemo-preventive food components that are rich in fruits and vegetables. In this study, flavokawain A (FKA, 2-30 μM), a naturally occurring chalcone in kava extracts, was evaluated for its anti-fibrotic and antioxidant properties in TGF-β1-stimulated vascular smooth muscle (A7r5) cells, as well as its underlying molecular mechanism of action. Immunofluorescence data showed down-regulated F-actin expression with FKA treatment in TGF-β1-stimulated A7r5 cells. Western blotting demonstrated that FKA treatment suppressed the expression of α-SMA and fibronectin proteins under TGF-β1 stimulation. Findings from wound-healing and invasion experiments showed that FKA inhibits TGF-β1-mediated migration and invasion. Western blotting demonstrated that treatment with FKA down-regulated MMP-9 and MMP-2 and up-regulated TIMP-1 expression. Further evidence showed that FKA decreased TGF-β1-mediated phosphorylation and the transcriptional activity of Smad3. TGF-β1-induced excessive ROS production was remarkably reversed by FKA treatment in A7r5 cells, and inhibition by FKA or N-acetylcysteine (NAC) substantially diminished TGF-β1-induced p-Smad3 activation and wound-healing migration. Interestingly, FKA-mediated antioxidant properties were associated with increased nuclear translocation of Nrf2 and elevated antioxidant response element (ARE) luciferase activity. Activation of Nrf2/ARE signaling was accompanied by the induction of HO-1, NQO-1 and γ-GCLC genes in FKA-treated A7r5 cells. Notably, silencing of Nrf2 (siRNA transfection) significantly diminished the FKA-mediated antioxidant effects, indicating that FKA may inhibit TGF-β1-induced fibrosis through suppressing ROS generation in A7r5 cells. Our results suggested that anti-fibrotic and antioxidant activities of the chalcone flavokawain A may contribute to the development of food-based chemo-preventive drugs for fibrotic diseases.
      PPARγ maintains the metabolic heterogeneity and homeostasis of renal tubules
      Lyu Z, Mao Z, Li Q, Xia Y, Liu Y, He Q, Wang Y, Zhao H, Lu Z and Zhou Q
      The renal tubules, which have distant metabolic features and functions in different segments, reabsorb >99% of approximately 180 l of water and 25,000 mmol of Na  daily. Defective metabolism in renal tubules is involved in the pathobiology of kidney diseases. However, the mechanisms underlying the metabolic regulation in renal tubules remain to be defined.
      Genistein attenuates renal fibrosis in streptozotocin‑induced diabetic rats
      Jia Q, Yang R, Liu XF, Ma SF and Wang L
      The present study aimed to investigate the antifibrogenic effects of genistein (GEN) on the kidney in streptozotocin (STZ)‑induced diabetic rats and to determine the associated mechanisms. Rats were randomized into four groups: Normal control (N), STZ (S), L (STZ + low‑dose GEN) and H (STZ + high‑dose GEN). After 8 weeks, the fasting blood glucose (FBG) level, the ratio of kidney weight to body weight (renal index), 24‑h urine protein, blood urea nitrogen (BUN), serum creatinine (SCr), renal total antioxidant capacity (T‑AOC), superoxide dismutase (SOD), lipid peroxidation (LPO), malondialdehyde (MDA) and hydroxyproline (Hyp) contents were measured. The histomorphology and ultrastructure of the kidney were also assessed. In addition, mRNA expression levels of transforming growth factor‑β1 (TGF‑β1) and protein expression levels of nuclear factor erythroid 2‑related factor 2 (Nrf2), heme oxygenase‑1 (HO‑1), NAD(P)H:quinone oxidoreductase 1 (NQO1), TGF‑β1, mothers against decapentaplegic homolog 3 (Smad3), phosphorylated (p)‑Smad3 and collagen IV were estimated. Compared with group N, the levels of FBG, renal index, 24‑h urine protein, BUN, SCr, LPO, MDA and Hyp were increased, whereas the levels of T‑AOC and SOD were decreased in group S. The structure of renal tissue was damaged, and the expression of Nrf2, HO‑1 and NQO1 were reduced, whereas the expression of TGF‑β1, Smad3, p‑Smad3 and collagen IV were increased in group S. Compared with group S, the aforementioned indices were improved in groups L and H. In conclusion, GEN exhibited reno‑protective effects in diabetic rats and its mechanisms may be associated with the inhibition of oxidative stress by activating the Nrf2‑HO‑1/NQO1 pathway, and the alleviation of renal fibrosis by suppressing the TGF‑β1/Smad3 pathway.
      Autophagy is a gatekeeper of hepatic differentiation and carcinogenesis by controlling the degradation of Yap
      Lee YA, Noon LA, Akat KM, Ybanez MD, Lee TF, Berres ML, Fujiwara N, Goossens N, Chou HI, Parvin-Nejad FP, Khambu B, Kramer EGM, Gordon R, Pfleger C, Germain D, John GR, Campbell KN, Yue Z, Yin XM, Cuervo AM, Czaja MJ, Fiel MI, Hoshida Y and Friedman SL
      Activation of the Hippo pathway effector Yap underlies many liver cancers, however no germline or somatic mutations have been identified. Autophagy maintains essential metabolic functions of the liver, and autophagy-deficient murine models develop benign adenomas and hepatomegaly, which have been attributed to activation of the p62/Sqstm1-Nrf2 axis. Here, we show that Yap is an autophagy substrate and mediator of tissue remodeling and hepatocarcinogenesis independent of the p62/Sqstm1-Nrf2 axis. Hepatocyte-specific deletion of Atg7 promotes liver size, fibrosis, progenitor cell expansion, and hepatocarcinogenesis, which is rescued by concurrent deletion of Yap. Our results shed new light on mechanisms of Yap degradation and the sequence of events that follow disruption of autophagy, which is impaired in chronic liver disease.
      Amitriptyline attenuates bleomycin-induced pulmonary fibrosis: modulation of the expression of NF-κβ, iNOS, and Nrf2
      Zaafan MA, Haridy AR and Abdelhamid AM
      Amitriptyline is a tricyclic antidepressant that was suggested to have antifibrotic potential. The current study aimed to investigate the modulatory effects of amitriptyline on bleomycin-induced pulmonary fibrosis in rats. Rats were randomly assigned into 4 groups: normal control, bleomycin control, amitriptyline+bleomycin, and amitriptyline only treated group. Lung injury was evaluated through the histological examination and immunohistochemical detection of α-smooth muscle actin (α-SMA) in lung tissue, in addition to the biochemical assessment of pulmonary contents of hydroxyproline and transforming growth factor beta-1 (TGF-β1). In addition, the following parameters were investigated for studying the possible mechanisms of amitriptyline antifibrotic effect: inducible nitric oxide synthase (iNOS), nuclear factor-κβ (NF-κβ), tumor necrosis factor-alpha (TNF-α), serpine-1, p53, nuclear factor erythroid 2-related factor 2 (Nrf2), lipid peroxides, and reduced glutathione (GSH). Amitriptyline exhibited potent antifibrotic effect that was reflected upon the histopathological examination and through its ability to suppress all the fibrotic parameters. Amitriptyline successfully suppressed the expression of NF-κβ, Nrf2, iNOS, and p53 in lung tissues besides the inhibition of other oxidative stress and inflammatory mediators. Amitriptyline could be a promising treatment to pulmonary fibrosis. Amitriptyline not only prevents the depression and its drawbacks in patients suffering from pulmonary fibrosis but also it can suppress fibrosis through variable mechanisms mainly via inhibition of NF-κβ/TNF-α/TGF-β pathway in addition to inhibition of Nrf2 and iNOS expression.
      Schisandrin B alleviates diabetic nephropathy through suppressing excessive inflammation and oxidative stress
      Mou Z, Feng Z, Xu Z, Zhuang F, Zheng X, Li X, Qian J and Liang G
      Diabetic nephropathy (DN) is a progressive kidney disease due to glomerular capillary damage in diabetic patients, with inflammation and oxidative stress implicated as crucial pathogenic factors. There is an urgent need to develop effective therapeutic drug. Natural medicines are rich resources for active lead compounds. They would provide new opportunities for the treatment of DN. The present study was designed to investigate the protective effects of Schisandrin B (SchB) on DN and to delineate the underlying mechanism. Oral administration of SchB in the diabetic mouse model significantly alleviated hyperglycemia-induced renal injury, which was accompanied by maintenance of urine creatinine and albumin levels at similar to those of control non-diabetic mice. Histological examination of renal tissue indicated that both development of fibrosis and renal cell apoptosis were dramatically inhibited by SchB. The protective effect of SchB on DN associated with suppression of inflammatory response and oxidative stress. These results strongly suggested that SchB could be a potential therapeutic agent for treatment of DN. Moreover, our findings provided a fuller understanding of the regulatory role of NF-κB and Nrf2 in DN, indicating that they could be important therapeutic targets.
      Diabetic cardiomyopathy: molecular mechanisms, detrimental effects of conventional treatment, and beneficial effects of natural therapy
      Parim B, Sathibabu Uddandrao VV and Saravanan G
      Diabetic complications are among the largely exigent health problems currently. Cardiovascular complications, including diabetic cardiomyopathy (DCM), account for more than 80% of diabetic deaths. Investigators are exploring new therapeutic targets to slow or abate diabetes because of the growing occurrence and augmented risk of deaths due to its complications. Research on rodent models of type 1 and type 2 diabetes mellitus, and the use of genetic engineering techniques in mice and rats have significantly sophisticated for our understanding of the molecular mechanisms in human DCM. DCM is featured by pathophysiological mechanisms that are hyperglycemia, insulin resistance, oxidative stress, left ventricular hypertrophy, damaged left ventricular systolic and diastolic functions, myocardial fibrosis, endothelial dysfunction, myocyte cell death, autophagy, and endoplasmic reticulum stress. A number of molecular and cellular pathways, such as cardiac ubiquitin proteasome system, FoxO transcription factors, hexosamine biosynthetic pathway, polyol pathway, protein kinase C signaling, NF-κB signaling, peroxisome proliferator-activated receptor signaling, Nrf2 pathway, mitogen-activated protein kinase pathway, and micro RNAs, play a major role in DCM. Currently, there are a few drugs for the management of DCM and some of them have considerable adverse effects. So, researchers are focusing on the natural products to ameliorate it. Hence, in this review, we discuss the pathogical, molecular, and cellular mechanisms of DCM; the current diagnostic methods and treatments; adverse effects of conventional treatment; and beneficial effects of natural product-based therapeutics, which may pave the way to new treatment strategies. Graphical Abstract.
      Impaired endothelial autophagy promotes liver fibrosis by aggravating the oxidative stress response during acute liver injury
      Ruart M, Chavarria L, Campreciós G, Suárez-Herrera N, Montironi C, Guixé-Muntet S, Bosch J, Friedman SL, Garcia-Pagán JC and Hernández-Gea V
      Endothelial dysfunction plays an essential role in liver injury, yet the phenotypic regulation of liver sinusoidal endothelial cells (LSECs) remains unknown. Autophagy is an endogenous protective system whose loss could undermine LSEC integrity and phenotype. The aim of our study was to investigate the role of autophagy in the regulation of endothelial dysfunction and the impact of its manipulation during liver injury.
      Downregulation of HMGB1 is required for the protective role of Nrf2 in EMT-mediated PF
      Qu J, Zhang Z, Zhang P, Zheng C, Zhou W, Cui W, Xu L and Gao J
      Epithelial-mesenchymal transition (EMT) is considered to be the key event in the formation of pulmonary fibrosis (PF). High-mobility group box 1 (HMGB1) is a novel mediator of EMT. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a critical transcription factor for protecting against PF. However, it is unknown the relationship between Nrf2 and HMGB1 in EMT-mediated PF. Bleomycin (BLM)-induced PF in Nrf2-knockout (Nrf2 ) and wild-type (WT) mice and transforming growth factor β1 (TGF-β1)-induced EMT in rat type II alveolar epithelial cell line (RLE-6TN) and human alveolar epithelial cell line (A549) were established to observe the relationship among Nrf2, HMGB1, and EMT by western blot and immunohistochemistry. BLM-induced EMT was more severe and the expression of HMGB1 was more increased in Nrf2 mice compared with WT mice. In vitro, Nrf2 activation attenuated TGF-β1-induced EMT and ROS production accompanied by the downregulation of HMGB1. In contrast, silencing Nrf2 enhanced TGF-β1-induced EMT and ROS production along with increased the protein expression and the release of HMGB1. Moreover, HMGB1 activation aggravated TGF-β1-induced EMT and HMGB1 deficiency alleviated TGF-β1-induced EMT. Furthermore, HMGB1 silence attenuated the protective effect of Nrf2 on EMT. These findings suggest downregulation of HMGB1, which is required for the protective role of Nrf2 in EMT-mediated PF and provide an important therapeutic target for PF.
      Reduction of renal tubular injury with a RAGE inhibitor FPS-ZM1, valsartan and their combination in streptozotocin-induced diabetes in the rat
      Sanajou D, Ghorbani Haghjo A, Argani H, Roshangar L, Rashtchizadeh N, Ahmad SNS, Ashrafi-Jigheh Z, Bahrambeigi S, Asiaee F, Rashedi J and Aslani S
      Receptor for advanced glycation end-products (RAGE) is involved in the pathogenesis of diabetic nephropathy. FPS-ZM1, a selective RAGE inhibitor, in combination with valsartan were investigated for their protective potentials on the renal markers of tubular injury in streptozotocin-induced diabetic rats. Rats were assigned into groups of receiving FPS-ZM1 (1 mg/kg/day), valsartan (100 mg/kg/day), and FPS-ZM1 plus valsartan (1 mg/kg/day and 100 mg/kg/day, respectively) for one month. Kidney histology, renal inflammation and oxidative stress, and renal and urinary markers of tubular injury were investigated. FPS-ZM1 and valsartan in combination more significantly attenuated renal expressions of tumor necrosis factor-alpha and interleukin-6 genes and reduced urinary levels of interleukin-6. Moreover, the combination elevated renal NAD/NADH ratios and Sirt1 activities, and mitigated nuclear acetylated NF-κB p65 levels. In addition to alleviating indices of oxidative stress i.e. malondialdehyde, superoxide dismutase and glutathione peroxidase, the combination of FPS-ZM1 and valsartan more effectively upregulated the renal levels of master antioxidant proteins Nrf2, heme oxygenase-1, and NAD(P)H:quinone oxidoreductase-1. Additionally, this dual therapy ameliorated more efficiently the indices of renal tubular injuries as indicated by decreased renal kidney injury molecule-1 levels as well as reduced urinary levels of cystatin C, retinol binding protein, and beta-2-microglobulin. While FPS-ZM1 alone had no appreciable effects on the renal fibrosis, the combination treatment ameliorated fibrosis better than valsartan in the kidneys. Collectively, these findings underline the extra benefits of FPS-ZM1 and valsartan dual administrations in obviating the renal tubular cell injury in streptozotocin-induced diabetic rats partly by suppressing renal inflammation and oxidative stress.
      CB1 receptor blockade ameliorates hepatic fat infiltration and inflammation and increases Nrf2-AMPK pathway in a rat model of severely uncontrolled diabetes
      Chang E, Kim DH, Yang H, Lee DH, Bae SH and Park CY
      Previous studies have shown that the CB1 receptor antagonist reverses steatohepatitis and its related features of metabolic syndrome, such as obesity and type 2 diabetes. However, the beneficial effects of CB1 receptor blockade on hepatic steatosis and inflammation have not been investigated independently of its effects on body weight and glycemic control. At 32 weeks of age, OLETF rats were administered with rimonabant (10 mg·kg-1·day-1) by oral gavage for 6 weeks. No significant changes in body weight, OGTT, and serum glucose were observed in spite of rimonabant-decreased food intake. Moreover, there was a significant difference between initial and final body weight, regardless of rimonabant administration, indicating that OLETF rats were severely diabetic rats. Rimonabant administration significantly decreased serum liver enzyme levels such as ALT and AST, hepatic fat accumulation, lipid peroxidation, and cell death as demonstrated by the number of TUNEL-positive cells in severely uncontrolled diabetic OLETF rats. Significant decreases in hepatic gene expression of proinflammatory cytokines (CD11b, F4/80, MCP1, and TNFα), negative inflammatory mediators (SOCS1 and SOCS3), and fibrosis-related proteins (TGFβ, collagen 1, and TIMP1) were found in rimonabant-treated OLETF rats. Six-week administration of rimonabant significantly upregulated mRNA levels of CPT1α and PPARα related to β-oxidation. Moreover, significant increases in Nrf2 gene expression and its downstream genes, NQO1, GSAT, HO-1, and TXNRD1 along with increased AMPK phosphorylation were noted in uncontrolled diabetic rats treated with rimonabant. The observed potent inhibitory effects of CB1 receptor blockade on hepatic fat infiltration and cellular death in severely uncontrolled diabetic rats indicate that CB1 receptor is a possible therapeutic target. Increased Nrf2 and AMPK phosphorylation may play a role in the mechanism of rimonabant action.
      Inhibitory Effects of Momordicine I on High-Glucose-Induced Cell Proliferation and Collagen Synthesis in Rat Cardiac Fibroblasts
      Chen PY, Shih NL, Hao WR, Chen CC, Liu JC and Sung LC
      Diabetes-associated cardiac fibrosis is a severe cardiovascular complication. Momordicine I, a bioactive triterpenoid isolated from bitter melon, has been demonstrated to have antidiabetic properties. This study investigated the effects of momordicine I on high-glucose-induced cardiac fibroblast activation. Rat cardiac fibroblasts were cultured in a high-glucose (25 mM) medium in the absence or presence of momordicine I, and the changes in collagen synthesis, transforming growth factor-1 (TGF-1) production, and related signaling molecules were assessed. Increased oxidative stress plays a critical role in the development of high-glucose-induced cardiac fibrosis; we further explored momordicine I's antioxidant activity and its effect on fibroblasts. Our data revealed that a high-glucose condition promoted fibroblast proliferation and collagen synthesis and these effects were abolished by momordicine I (0.3 and 1 M) pretreatment. Furthermore, the inhibitory effect of momordicine I on high-glucose-induced fibroblast activation may be associated with its activation of nuclear factor erythroid 2-related factor 2 (Nrf2) and the inhibition of reactive oxygen species formation, TGF-1 production, and Smad2/3 phosphorylation. The addition of brusatol (a selective inhibitor of Nrf2) or Nrf2 siRNA significantly abolished the inhibitory effect of momordicine I on fibroblast activation. Our findings revealed that the antifibrotic effect of momordicine I was mediated, at least partially, by the inhibition of the TGF-1/Smad pathway, fibroblast proliferation, and collagen synthesis through Nrf2 activation. Thus, this work provides crucial insights into the molecular pathways for the clinical application of momordicine I for treating diabetes-associated cardiac fibrosis.
      Notoginsenoside R1 Protects Against Diabetic Cardiomyopathy Through Activating Estrogen Receptor α and Its Downstream Signaling
      Zhang B, Zhang J, Zhang C, Zhang X, Ye J, Kuang S, Sun G and Sun X
      Diabetic cardiomyopathy (DCM) leads to heart failure and death in diabetic patients, no effective treatment is available. Notoginsenoside R1 (NGR1) is a novel saponin that is derived from Panax notoginseng and our previous studies have showed cardioprotective and neuroprotective effects of NGR1. However, its role in protecting against DCM remains unexplored. Herein, we examine potential effects of NGR1 on cardiac function of diabetic db/db mice and H9c2 cardiomyocytes treated by advanced glycation end products (AGEs). experiments revealed that pretreatment with NGR1 significantly decreased AGEs-induced mitochondria injury, limited an increase in ROS, and reduced apoptosis in H9c2 cells. NGR1 eliminated ROS by promoting estrogen receptor α expression, which subsequently activated Akt and Nrf2-mediated anti-oxidant enzymes. investigation demonstrated that NGR1 significantly reduced serum lipid levels, insulin resistance, the expression of enzymes related to cardiomyopathy, and the expression of apoptotic proteins. Finally, NGR1 improved cardiac dysfunction and attenuated histological abnormalities, as evidenced by elevating ejection fraction and fractional shortening, and reducing cardiac fibrosis. Mechanistically, NGR1 promoted ERα expression, which led to the activation of Akt-Nrf2 signaling and the inhibition of the TGFβ pathway. Collectively, these results strongly indicate that NGR1 exerts cardioprotective effects against DCM through its inhibition of oxidative stress and apoptosis, and eventually suppresses cardiac fibrosis and hypertrophy, which suggests that NGR1 is a potential therapeutic medicine for the treatment of DCM.
      Asiatic acid ameliorates CCl-induced liver fibrosis in rats: involvement of Nrf2/ARE, NF-κB/IκBα, and JAK1/STAT3 signaling pathways
      Fan J, Chen Q, Wei L, Zhou X, Wang R and Zhang H
      Currently, there are no effective therapies for liver fibrosis; hence, the development of anti-liver fibrosis agents is urgently needed. Here, we attempted to investigate the therapeutic effect and mechanism of asiatic acid (AA) on liver fibrosis, mainly focusing on the impact of AA on nuclear erythroid 2-related factor 2/antioxidant response element (Nrf2/ARE), nuclear factor-kappa B (NF-κB)/IκBα, and JAK1/signal transducer and activator of transcription 3 (STAT3) signaling pathways.
      Tanshinone IIA Inhibits High Glucose-Induced Collagen Synthesis via Nuclear Factor Erythroid 2-Related Factor 2 in Cardiac Fibroblasts
      Tsai YT, Loh SH, Lee CY, Lee SP, Chen YL, Cheng TH and Tsai CS
      Diabetes is associated with increased incidence of myocardial dysfunction, which is partly characterized by interstitial and perivascular fibrosis. Cardiac fibroblasts have been identified as an important participant in the development of cardiac fibrosis. Exposure of cultured cardiac fibroblasts to high glucose resulted in increased collagen synthesis. Tanshinone IIA can alleviate the ventricular fibrosis that develops in a number of different experimental conditions. However, whether tanshinone IIA can prevent high glucose-induced collagen synthesis in cardiac fibroblasts remains unknown. The aim of this study was to evaluate the effects of tanshinone IIA on high glucose-induced collagen synthesis in cardiac fibroblasts.

      JOIN OUR COMMUNITY.

      Reach Us

      Our mission is to provide an impartial review of the emerging research regarding Nrf2 activation.

      We welcome the involvement of those who have published peer review studies in this field. 

      Should you wish to contact us, please leave a message using the adjacent form. 

       

        Researching Nrf2? Leave us a message to collaborate

        Inflammation: A Major Contributor to Disease and Aging. Can Nrf2 Help Reduce It?

        Inflammation: A Major Contributor to Disease and Aging. Can Nrf2 Help Reduce It?

        English: PET scan of a human brain with Alzhei...

        As the boomer generation ages, it is probable that there will be more posts such as the one I saw this week from a friend on Facebook. Their plea was for suggestions and recommendations for a good solution to help alleviate the pain they were experiencing from inflammation.

        Externally, inflammation can be recognized by redness, swelling and pain. Internally, it is a lot more difficult to recognize and may well go undetected for long periods of time.  The effects of inflammation can also range from minor to chronic. An example of a minor case of inflammation may include bacteria causing an infection such as from a splinter piercing the skin. The more serious chronic inflammation may be a common factor in many age-related diseases such as Diabetes, arthritis, heart disease, cancer or Alzheimer’s.

        There are over 500 results on Pubmed.gov when searching for NRF2 and inflammation. A couple of examples of the positive role that NRF2 had on inflammation.

        The first study we will highlight is one called “Transcription Factor Nrf2 Regulates Inflammation” which was published in the Journal of Molecular and Cellular Biology. This inflammation. study dates back to 2003 in which two groups of mice with pleurisy were tested. The one group was treated with a Nrf2 activator, cyclooxygenase 2 inhibitor NS-398 the other group was not treated.  The conclusion of the study shows that the mice with elevated NRF2 had less inflammation than the mice that were not treated.

        “Administration of 15d-PGJ into the pleural space of NS-398-treated wild-type mice largely counteracted both the decrease in PrxI and persistence of neutrophil recruitment. In contrast, these changes did not occur in the Nrf2-deficient mice. These results demonstrate that Nrf2 regulates the inflammation process downstream of 15d-PGJ by orchestrating the recruitment of inflammatory cells and regulating the gene expression within those cells.”

        The following study “Nrf2 is essential for cholesterol crystal-induced inflammasome activation and exacerbation of atherosclerosis.” Published in the
        European Journal of Immunology. shows the interaction between NRF2 and the inflammation-causing protein called inflammasome.

        Quoting from the study, “Here we have identified the oxidative stress-responsive transcription factor NF-E2-related 2 (Nrf2) as an essential positive regulator of inflammasome activation and IL-1-mediated vascular inflammation. We show that cholesterol crystals, which accumulate in atherosclerotic plaques, represent an endogenous danger signal that activates Nrf2 and the NLRP3 inflammasome.”

        So, in response to my friend looking for solutions to their inflammation concerns, we suggest researching further in Pubmed and other reputable journals as well as getting the advice of a healthcare professional.

        Here are the latest Nrf2 Studies regarding inflammation: 

         

        Mate tea reduces high fat diet-induced liver and metabolic disorders in mice
        Barroso MV, Graça-Reis A, Cattani-Cavalieri I, Gitirana LB, Valenca SS and Lanzetti M
        High-fat diet (HFD)-induced obesity is a worldwide health problem and can cause lipid accumulation in the liver. We evaluated the hepatoprotective effect of mate tea treatment in mice submitted to an HFD. C57BL/6 mice were fed an HFD for 13 weeks with and without mate tea. A separate group of mice was treated with fenofibrate as a positive control (a regular drug for lipid disorders). Histological analyses, glucose tolerance tests (GTT), and quantification of mediators related to lipid peroxidation, oxidative stress and blood biomarkers for lipid profile were performed. The weight of animals and major organs related to hepatic steatosis was determined, and proinflammatory cytokines and the participation of the Nrf2 pathway and adiponectin were evaluated. Mate tea prevented the accumulation of lipid droplets in hepatocytes as well as weight gain in animals submitted to the HFD. Mate tea treatment also prevented increases in the liver weight, heart weight and amount of visceral and subcutaneous white adipose tissue. Mate tea was able to prevent the deregulation of glucose uptake, as evaluated by GTT, and improved the indicators of oxidative stress, such as nitrite levels, catalase activity, and oxidative damage, as evaluated by protein carbonylation and the MDA levels. Mate tea had an anti-inflammatory effect, preventing the increase of IL-1β and KC and upregulating the expression of Nrf2. Mate tea prevented insulin increase and HDL cholesterol decrease but did not affect total cholesterol or triglycerides levels. Treatment also prevented adiponectin increase. Mate tea may be a good resource to reduce hepatic steatosis in the future since it has anti-diabetic, anti-inflammatory and antioxidant effects, which prevent the accumulation of fat in the liver.
        Inhibition of TREM1 reduces inflammation and oxidative stress after spinal cord injury (SCI) associated with HO-1 expressions
        Li Z, Wu F, Xu D, Zhi Z and Xu G
        Spinal cord injury (SCI) is a devastating event, leading to the progression of chronic neuropathic pain syndrome. Triggering receptor expressed on myeloid cells 1 (TREM1) is an innate immune receptor expressed on neutrophils and monocytes/macrophages. TREM1 enhances inflammatory response in various models of diseases, but its significance in SCI remains unclear. In the present study, we attempted to explore the effects of TREM1 on the regulation of SCI. Spinal cord contusion injury was performed in wild type (WT) and TREM1-knockout (TREM1) mice, and real time-quantitative PCR (RT-qPCR), western blot, and immunofluorescent (IF) staining were used to calculate TREM1, inflammation and oxidative stress in spinal cord tissues 42 days after SPII. In vitro, astrocytes (AST) and BV2 cells were transfected TREM siRNA or the negative control (NC) siRNA to knockdown (KD) TREM1 expressions, followed by lipopolysaccharide (LPS) stimulation to verify the role od TREM1 in modulating SPI. The results suggested that TREM1 was highly expressed in the spinal cord tissues of WT mice after SCI. TREM mice exhibited improved locomotor function, mechanical and thermal hypersensitivity in the hindpaws after SCI. In addition, peripheral nerve injury-related biomarkers were down-regulated by TREM1 in SCI mice. TREM1 increased NeuN-stained cells, and decreased GFAP and Iba-1 expressions in spinal cord tissues of mice after SCI. TREM1 mice showed reduced expressions of inflammation-related regulators in the injured spinal cord. Further, toll like receptors (TLR-2, -3, -4, and -9), p-IκBα and p-nuclear factor-kappa B (NF-κB) protein expression levels were markedly decreased by TREM1 in mice after SCI injury. Moreover, TREM-deficiency suppressed oxidative stress markers, while enhanced anti-oxidants, such as superoxide dismutase-1 (SOD1), NAD(P)H:quinone oxidoreductase-1 (NQO-1), heme oxygenase-1 (HO-1) and nuclear factor E2-related factor 2 (Nrf2) in the injured spinal cord. The in vivo results mentioned above were verified in LPS-stimulated AST and BV2 cells in vitro. Of note, the in vitro results also demonstrated that suppressing HO-1 expressions using Zn-protoporphyrin (ZnPP) abrogated TREM1-reduced inflammation, oxidative stress and glial cells activation. The results above demonstrated that suppressing TREM1 expressions markedly improved the outcome of SCI, most likely through reducing inflammation and oxidative stress at least partly regulated by HO-1 expressions. TREM1 inhibition might be therefore has potential as a therapeutic target after SCI.
        Apigetrin treatment attenuates LPS-induced acute otitis media though suppressing inflammation and oxidative stress
        Guo H, Li M and Xu LJ
        The natural course of otitis media in children is acute and self-limiting. Nevertheless, about 10-20% children could experience recurrent or persistent otitis media. Thus, finding effective candidate to prevent acute otitis media is urgently required. In our study, mouse acute otitis media model was constructed by lipopolysaccharide (LPS) injection into the middle ear of mice via the tympanic membrane. Apigetrin (APT) is a flavonoid isolated from various herbal medicines, possessing anti-inflammatory and anti-oxidative bioactivities. However, if APT could attenuate acute otitis media in LPS-induced animal models, little is to be known. Hematoxylin and eosin (H&E) staining suggested that APT treatment reduced LPS-induced higher mucosa thickness. LPS-triggered inflammatory response was also inhibited by APT, as evidenced by the down-regulated neutrophils and macrophages. Additionally, the reduced inflammatory factors, including interleukin-1β (IL-lβ), tumor necrosis factor α (TNF-α), IL-6 and vascular endothelial growth factor (VEGF) were observed in APT-treated mice with acute otitis media. The process was associated with the inhibition of toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) pathway, which was proved by the blockage of TLR4, MyD88, p-IKKα, p-IκBα, and p-NF-κB using western blot analysis. Moreover, the production of reactive oxygen species (ROS) caused by LPS was also reduced by APT through promoting anti-oxidants, involving superoxide dismutase (SOD) activity, heme oxygenase-1 (HO-1), NADP(H) quinone oxidoreductase 1 (NQO-1) and nuclear factor erythroid 2-related factor 2 (Nrf2) expressions. In contrast, high levels of MDA and kelch-like ECH-associated protein 1 (Keap 1) in LPS-treated mice were down-regulated by APT, which might be associated with the inactivation of NF-κB. In vitro, APT exhibited anti-inflammatory and anti-oxidant effects with little cytotoxicity in LPS-stimulated cells. Together, the data above indicated that APT could ameliorate acute otitis media through inhibiting inflammation and oxidative stress.
        Traditional Chinese medicine Gegen Qinlian decoction ameliorates irinotecan chemotherapy-induced gut toxicity in mice
        Wu Y, Wang D, Yang X, Fu C, Zou L and Zhang J
        Gegen Qinlian decoction (GQT), is a classic traditional Chinese medicine formula chronicled in Shang Han Lun, and is widely used to treat diarrhea and inflammation symptoms in various gastrointestinal disorders. Although it has been found to inhibit delayed-onset mice diarrhea resulted from irinotecan (CPT-11) administration in preliminary experiments, the underlying mechanisms and chemical components remain elusive.
        Hydroxytyrosol supplementation ameliorates the metabolic disturbances in white adipose tissue from mice fed a high-fat diet through recovery of transcription factors Nrf2, SREBP-1c, PPAR-γ and NF-κB
        Illesca P, Valenzuela R, Espinosa A, Echeverría F, Soto-Alarcon S, Ortiz M and Videla LA
        White adipose tissue (WAT) have a relevant metabolic and inflammatory function, in overweight or obesity conditions. In this regard, the WAT under over feeding nutrition present a significant increment in oxidative stress, pro-inflammatory status and depletion of n-3 long chain polyunsaturated fatty acid. Hydroxytyrosol (HT) is a polyphenol with important cytoprotective effects, and this molecule can modulate the gene expression, transcription factors and enzymatic activity.
        Blocking of tripartite motif 8 protects against lipopolysaccharide (LPS)-induced acute lung injury by regulating AMPKα activity
        Xiaoli L, Wujun Z and Jing L
        Acute lung injury (ALI) and its more serious form, respiratory distress syndrome (ARDS), are considered as an acute and severe inflammatory process existing in lungs, and still remain high mortality rates. Tripartite motif 8 (TRIM8) contains an N-terminal RING finger, which is followed by two B-boxes and a coiled-coil domain, belonging to the TRIM/RBCC family and playing significant role in meditating inflammation, oxidative stress and apoptosis. In the study, we investigated the role of TRIM8 in ALI induced by lipopolysaccharide (LPS) and the underlying molecular mechanisms. The in vitro results indicated that LPS time-dependently enhanced TRIM8 expression in lung epithelial cells. Suppressing TRIM8 markedly ameliorated LPS-elicited inflammatory response, as evidenced by the down-regulated mRNA levels of interleukin-1β (IL-1β), IL-6 and tumor necrosis factor-α (TNF-α) in cells mainly through inactivating nuclear factor-kappa B (NF-κB) signaling pathway; however, over-expressing TRIM8 markedly promoted inflammation in LPS-challenged cells. In addition, LPS-induced oxidative stress was accelerated by TRIM8 over-expression, while being alleviated by TRIM8 knockdown by regulating Nrf2 signaling. Importantly, TRIM8 could negatively meditate AMP-activated protein kinase-α (AMPKα) activation to modulate LPS-triggered inflammatory response and ROS generation in vitro. Additionally, our in vivo findings suggested that TRIM8 knockdown effectively attenuated LPS-induced lung injury nu decrease of lung wet/dry (W/T) ratio, protein concentrations, neutrophil infiltration, myeloperoxidase (MPO) activity, reactive oxygen species (ROS) production and superoxide dismutase (SOD) depletion. Meanwhile, the loss of TRIM8 markedly lessened IL-1β, IL-6 and TNF-α expression in lung tissues of LPS-challenged mice, and reduced NF-κB phosphorylation. Furthermore, TRIM8 knockdown evidently improved nuclear factor-erythroid 2 related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) expressions in lung of LPS-treated mice. The anti-inflammation and anti-oxidant role of TRIM8-silence might be associated with AMPKα phosphorylation. Together, our study firstly provided a support that TRIM8 knockdown effectively protected LPS-induced ALI against inflammation and oxidative stress largely dependent on the promotion of AMPKα pathway.
        Sulforaphane enriched transcriptome of lung mitochondrial energy metabolism and provided pulmonary injury protection via Nrf2 in mice
        Cho HY, Miller-DeGraff L, Blankenship-Paris T, Wang X, Bell DA, Lih F, Deterding L, Panduri V, Morgan DL, Yamamoto M, Reddy AJ, Talalay P and Kleeberger SR
        Nrf2 is essential to antioxidant response element (ARE)-mediated host defense. Sulforaphane (SFN) is a phytochemical antioxidant known to affect multiple cellular targets including Nrf2-ARE pathway in chemoprevention. However, the role of SFN in non-malignant airway disorders remain unclear. To test if pre-activation of Nrf2-ARE signaling protects lungs from oxidant-induced acute injury, wild-type (Nrf2) and Nrf2-deficient (Nrf2) mice were given SFN orally or as standardized broccoli sprout extract diet (SBE) before hyperoxia or air exposure. Hyperoxia-induced pulmonary injury and oxidation indices were significantly reduced by SFN or SBE in Nrf2 mice but not in Nrf2 mice. SFN upregulated a large cluster of basal lung genes that are involved in mitochondrial oxidative phosphorylation, energy metabolism, and cardiovascular protection only in Nrf2 mice. Bioinformatic analysis elucidated ARE-like motifs on these genes. Transcript abundance of the mitochondrial machinery genes remained significantly higher after hyperoxia exposure in SFN-treated Nrf2 mice than in SFN-treated Nrf2 mice. Nuclear factor-κB was suggested to be a central molecule in transcriptome networks affected by SFN. Minor improvement of hyperoxia-caused lung histopathology and neutrophilia by SFN in Nrf2 mice implies Nrf2-independent or alternate effector mechanisms. In conclusion, SFN is suggested to be as a preventive intervention in a preclinical model of acute lung injury by linking mitochondria and Nrf2. Administration of SFN alleviated acute lung injury-like pathogenesis in a Nrf2-dependent manner. Potential AREs in the SFN-inducible transcriptome for mitochondria bioenergetics provided a new insight into the downstream mechanisms of Nrf2-mediated pulmonary protection.
        Molecular hydrogen (H2): Potential in mitigating oxidative stress-induced cardiotoxicity
        Kura B, Bagchi AK, Singal PK, Barancik M, LeBaron TW, Valachova K, Soltes L and Slezak J
        Uncontrolled production of oxygen and nitrogen radicals results in oxidative (OS) and nitrosative (NS) stresses that impair cellular functions and have been regarded as causative common denominators of many pathological processes. In this review, we report on the beneficial effects of molecular hydrogen (H2) in scavenging radicals in an artificial system of ●OH formation. As a proof of principle, we also demonstrate that in rat hearts in vivo, administration of H2 led to a significant increase in SOD as well as pAKT, a cell survival signaling molecule. Irradiation of the rats caused a significant increase in lipid peroxidation which was mitigated by pre-treatment of the animals with molecular H2. The nuclear factor erythroid 2-related factor 2 (Nrf2) is regarded as an important regulator of oxyradical homeostasis as well as it supports the functional integrity of cells, particularly under conditions of OS. We suggest that the beneficial effects of H2 may be through the activation of Nrf2 pathway that promotes innate antioxidants and reduction of apoptosis as well as inflammation.
        Lotus seed skin proanthocyanidin extract exhibits potent antioxidant property via activation of the Nrf2-ARE pathway
        Li T, Li Q, Wu W, Li Y, Hou DX, Xu H, Zheng B, Zeng S, Shan Y, Lu X, Deng F and Qin S
        Lotus seed is well known as traditional food and medicine, but its skin is usually discarded. Recent studies have shown that lotus seed skin contains a high concentration of proanthocyanidins that have multi-functions, such as antioxidation, anti-inflammation, and anti-cancer effects. In the present study, we aimed to isolate and purify the proanthocyanidins from lotus seed skin by acetone extraction and rotary evaporation, identify their chemical structures by HPLC-MS-MS and NMR, and further investigate the antioxidant properties of the extract purified by macroporous resin (PMR) from lotus seed skin both in vitro and in vivo. The results showed that PMR mainly contained oligomeric proanthocyanidins, especially dimeric procyanidin B1 (PB1), procyanidin B2 and procyanidin B4. Although it had limited ability to directly scavenge radicals in vitro, PMR could significantly enhance the expressions of antioxidant proteins via activation of nuclear factor-E2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway in HepG2 cells. Molecular data revealed that PB1, a major component in PMR, stabilized Nrf2 by inhibiting the ubiquitination of Nrf2, which led to subsequent activation of the Nrf2-ARE pathway, including the enhancements of Nrf2 nuclear translocation, Nrf2-ARE binding and ARE transcriptional activity. Moreover, the in vivo results in high fat diet-induced mice further verified the powerful antioxidant property of PMR. These results revealed that lotus seed skin is a promising resource for functional food development.
        Hepatoprotective effect of chiisanoside from Acanthopanax sessiliflorus against LPS/D-GalN-induced acute liver injury by inhibiting NF-κB and activating Nrf2/HO-1 signaling pathways
        Bian X, Liu X, Liu J, Zhao Y, Li H, Zhang L, Li P and Gao Y
        In China, Acanthopanax sessiliflorus is a delicious wild vegetable. It is also used to treat of inflammation and pain. Considering that chiisanoside (CSS) is the main constituent of the leaf of A. sessiliflorus. Combined use of LPS/D-GalN can induce acute liver failure like human beings, and there are no reports on the protective effect of CSS against LPS/D-GalN-induced acute liver injury in mice.
        Molecular mechanism involved in cyclophosphamide-induced cardiotoxicity: Old drug with a new vision
        Iqubal A, Iqubal MK, Sharma S, Ansari MA, Najmi AK, Ali SM, Ali J and Haque SE
        Cyclophosphamide (CP) is an important anticancer drug which belongs to the class of alkylating agent. Cyclophosphamide is mostly used in bone marrow transplantation, rheumatoid arthritis, lupus erythematosus, multiple sclerosis, neuroblastoma and other types of cancer. Dose-related cardiotoxicity is a limiting factor for its use. CP-induced cardiotoxicity ranges from 7 to 28% and mortality ranges from 11 to 43% at the therapeutic dose of 170-180 mg/kg, i.v. CP undergoes hepatic metabolism that results in the production of aldophosphamide. Aldophosphamide decomposes into phosphoramide mustard & acrolein. Phosphoramide is an active neoplastic agent, and acrolein is a toxic metabolite which acts on the myocardium and endothelial cells. This is the first review article that talks about cyclophosphamide-induced cardiotoxicity and the different signaling pathways involved in its pathogenicity. Based on the available literature, CP is accountable for cardiomyocytes energy pool alteration by affecting the heart fatty acid binding proteins (H-FABP).CP has been found associated with cardiomyocytes apoptosis, inflammation, endothelial dysfunction, calcium dysregulation, endoplasmic reticulum damage, and mitochondrial damage. Molecular mechanism of cardiotoxicity has been discussed in detail through crosstalk of Nrf2/ARE, Akt/GSK-3β/NFAT/calcineurin, p53/p38MAPK, NF-kB/TLR-4, and Phospholamban/SERCA-2a signaling pathway. Based on the available literature we support the fact that metabolites of CP are responsible for cardiotoxicity due to depletion of antioxidants/ATP level, altered contractility, damaged endothelium and enhanced pro-inflammatory/pro-apoptotic activities resulting into cardiomyopathy, myocardial infarction, and heart failure. Dose adjustment, elimination/excretion of acrolein and maintenance of endogenous antioxidant pool could be the therapeutic approach to mitigate the toxicities.
        Melatonin receptor activation provides cerebral protection after traumatic brain injury by mitigating oxidative stress and inflammation via the Nrf2 signaling pathway
        Wang J, Jiang C, Zhang K, Lan X, Chen X, Zang W, Wang Z, Guan F, Zhu C, Yang X, Lu H and Wang J
        Traumatic brain injury (TBI) is a principal cause of death and disability worldwide. Melatonin, a hormone made by the pineal gland, is known to have anti-inflammatory and antioxidant properties. In this study, using a weight-drop model of TBI, we investigated the protective effects of ramelteon, a melatonin MT1/MT2 receptor agonist, and its underlying mechanisms of action. Administration of ramelteon (10mg/kg) daily at 10:00 am alleviated TBI-induced early brain damage on day 3 and long-term neurobehavioral deficits on day 28 in C57BL/6 mice. Ramelteon also increased the protein levels of interleukin (IL)-10, IL-4, superoxide dismutase (SOD), glutathione, and glutathione peroxidase and reduced the protein levels of IL-1β, tumor necrosis factor, and malondialdehyde in brain tissue and serum on days 1, 3, and 7 post-TBI. Similarly, ramelteon attenuated microglial and astrocyte activation in the perilesional cortex on day 3. Furthermore, ramelteon decreased Keap 1 expression, promoted nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear accumulation, and increased levels of downstream proteins, including SOD-1, heme oxygenase-1, and NQO1 on day 3 post-TBI. However, in Nrf2 knockout mice with TBI, ramelteon did not decrease the lesion volume, neuronal degeneration, or myelin loss on day 3; nor did it mitigate depression-like behavior or most motor behavior deficits on day 28. Thus, timed ramelteon treatment appears to prevent inflammation and oxidative stress via the Nrf2-antioxidant response element pathway and might represent a potential chronotherapeutic strategy for treating TBI.
        (Gaertn.) Roxb. Extract and Gallic Acid Attenuate LPS-Induced Inflammation and Oxidative Stress via MAPK/NF-B and Akt/AMPK/Nrf2 Pathways
        Tanaka M, Kishimoto Y, Sasaki M, Sato A, Kamiya T, Kondo K and Iida K
        Excessive oxidative stress plays a critical role in the progression of various diseases. Recently, we showed that (Gaertn.) Roxb. extract (TBE) inhibits inflammatory response and reactive oxygen species (ROS) production in THP-1 macrophages. However, molecular mechanisms underlying anti-inflammatory and antioxidant activities of TBE and its major polyphenolic compounds gallic acid (GA) and ellagic acid (EA) remain unclear. We found that TBE and GA attenuated LPS-induced inflammatory mediator expression, ROS production, and activation of mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-B) in RAW 264 macrophages. Furthermore, TBE and GA increased antioxidant enzyme expression along with upstream mediators nuclear factor erythroid-2-related factor 2 (Nrf2), Akt, and AMP-activated protein kinase (AMPK). Importantly, knockdown of Nrf2 by siRNA and specific inhibition of Akt and AMPK significantly reduced antioxidant enzyme expression induced by TBE and GA. Finally, effects on histopathology and gene expression were assessed in tissues collected after intraperitoneal injection of LPS with or without TBE treatment. TBE enhanced antioxidant enzyme expression and improved acute kidney injury in LPS-shock model mice. In conclusion, TBE and GA exert protective effects against inflammation and oxidative stress by suppressing MAPK/NF-B pathway and by activating Akt/AMPK/Nrf2 pathway. These results suggest that TBE and GA might be effective for the treatment of inflammation-related diseases.
        Protective Role of Nuclear Factor-Erythroid 2-Related Factor 2 Against Radiation-Induced Lung Injury and Inflammation
        Tian X, Wang F, Luo Y, Ma S, Zhang N, Sun Y, You C, Tang G, Li S, Gong Y and Xie C
        Radiation-induced lung injury (RILI) is one of the most common and fatal complications of thoracic radiotherapy. Inflammatory cell infiltration, imbalance of inflammatory cytokines, and oxidative damage were reported to be involved during RILI pathogenesis, especially in the early phase of RILI. Nuclear factor-erythroid 2-related factor 2 (Nrf2) is a key transcriptional regulator of antioxidative cascades, and regulates life span of mice after administration of thoracic irradiation. We investigated the effects of Nrf2 on RILI and inflammation using Nrf2-knockout, Nrf2-overexpression and wild-type mice with or without 15 Gy ionizing radiation to thorax. Our results showed that Nrf2 deficiency aggravated radiation-induced histopathological changes, macrophage and neutrophil infiltration, serum levels of pro-inflammatory cytokines (IL-6, MCP-1, IFN-γ, TNF, and IL-12p70), and the levels of peroxidation products in the mouse lung. Moreover, loss of Nrf2 reduced radiation-induced serum levels of anti-inflammatory cytokine, IL-10, and antioxidative proteins. Nrf2 overexpression significantly alleviated radiation-induced histopathological changes, macrophages and neutrophils infiltration, serum levels of pro-inflammatory cytokines, and the levels of peroxidation products in lung tissues. Nrf2 overexpression also increased the serum levels of IL-10 and antioxidative proteins. These results indicated that Nrf2 had a protective role against radiation-induced acute lung injury and inflammation, and that antioxidative therapy might be a promising treatment for RILI.
        DC32, a Dihydroartemisinin Derivative, Ameliorates Collagen-Induced Arthritis Through an Nrf2-p62-Keap1 Feedback Loop
        Fan M, Li Y, Yao C, Liu X, Liu J and Yu B
        Artemisinins have been reported to have diverse functions, such as antimalaria, anticancer, anti-inflammation, and immunoregulation activities. DC32 [(9α,12α-dihydroartemisinyl) bis(2'-chlorocinnmate)], a dihydroartemisinin derivative possessing potent immunosuppressive properties, was synthesized in our previous study. Collagen-induced arthritis (CIA) in DBA/1 mice and inflammatory model in NIH-3T3 cells were established to evaluate the effect of DC32 on RA and discover the underlying mechanisms. The results showed that DC32 could markedly alleviate footpad inflammation, reduce cartilage degradation, activate the Nrf2/HO-1 signaling pathway, and increase the transcription of p62 in DBA/1 mice with CIA. Further mechanistic exploration with NIH-3T3 cells indicated that DC32 could increase the transcription, expression, and nuclear translocation of Nrf2. In addition, DC32 promoted degradation of Keap1 protein and upregulated HO-1 and p62 expression. Furthermore, the effect of DC32 on Keap1 degradation could be prevented by p62 knockdown using siRNA. Administration of DC32 could inhibit the activation of Akt/mTOR and ERK, and pretreatment of NIH-3T3 cells with the autophagy inhibitor 3-methyladenine (3-MA) attenuated the degradation of Keap1 induced by DC32. These results suggest that DC32 inhibits the degradation of Nrf2 by promoting p62-mediated selective autophagy and that p62 upregulation contributed to a positive feedback loop for persistent activation of Nrf2. In summary, our present study demonstrated that DC32 significantly suppressed rheumatoid arthritis (RA) via the Nrf2-p62-Keap1 feedback loop by increasing the mRNA and protein levels of Nrf2 and inducing p62 expression. These findings provide new mechanisms for artemisinins in RA treatment and a potential strategy for discovering antirheumatic drugs.

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          Spring Cleaning Damaged Proteins with Nrf2: Good for Huntington’s Disease and Other Neurodegenerative Disorders?

          Spring Cleaning Damaged Proteins with Nrf2: Good for Huntington’s Disease and Other Neurodegenerative Disorders?

          English: Complete neuron cell diagram. Neurons...

          English: Complete neuron cell diagram. Neurons (also known as neurones and nerve cells) are electrically excitable cells in the nervous system that process and transmit information. In vertebrate animals, neurons are the core components of the brain, spinal cord and peripheral nerves. (Photo credit: Wikipedia)

          A new study supported by grants from NINDS and the National Institute on Aging as well as funding provided by the Taube/Koret Center, the National Science Foundation , the Huntington’s Disease Society of America, the Milton Wexler Award, and the Hillblom Foundation shows that activating a gene known as NRF2 helps clear damaged proteins which slows down or could possibly prevent Huntington’s disease.

          The study published in Nature Chemical Biology explains how important it is to quickly clear damaged proteins from neurons. Cell survival may be affected by the speed at which damaged proteins are removed. In Huntington’s disease and other neurodegenerative disorders, damaged proteins become misshaped and abnormal. They envelope neurons and damage or  kill the nearby brain cells. Healthy bodies are able to control quality and quantity of protein levels, as well as is able to detect malformed proteins and flush them be fore they can do any damage through a process called proteostasis.

          The study broke new ground in developing and using a technique called optical pulse-labeling to measure how quickly damaged proteins get removed. “Before this new technique, there was no way to look at individual neurons and their capacity to handle proteins. This method provides a real-time readout of how fast proteins are turned over in neurons and gives us a look at some of the mechanisms involved,” said Margaret Sutherland, Ph.D., program director at NINDS.

          The research studied the impact of different forms of huntingtin, the protein in Huntington’s disease on neuron death and the symptoms of the disease. The experiments showed that the mutant form of huntingtin caused more rat cells to die than the normal healthy form of the protein.

          To test this idea, the researchers activated Nrf2, a protein known to regulate protein processing. When Nrf2 was turned on, the mean lifetime of huntingtin was shortened, and the neuron lived longer. The researchers discovered that neuronal survival is directly correlated with the amount of time a neuron is exposed to the mutant huntingtin protein. Improving proteostasis in Huntington’s brains may improve neuronal survival and slow down or even prevent the the progression of the disease.

          “Nrf2 seems like a potentially exciting therapeutic target. It is profoundly neuroprotective in our Huntington’s model and it accelerates the clearance of mutant huntingtin,” said Dr. Steven Finkbeiner, senior author of the paper.

          “These findings provide evidence that our brains have powerful coping mechanisms to deal with disease-causing proteins. The fact that some of these diseases don’t cause symptoms we can detect until the fourth or fifth decade of life, even when the gene has been present since birth, suggests that those mechanisms are pretty good,” said Dr. Finkbeiner.
          Other NRF2 Huntington studies on Pubmed.org:

          Impaired mitochondrial dynamics and Nrf2 signaling contribute to compromised responses to oxidative stress in striatal cells expressing full-length mutant huntingtin.

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            A New Nrf2 and Diabetes Study Underway

            A New Nrf2 and Diabetes Study Underway

            Age-standardised disability-adjusted life year...

            The American Diabetes Journal has details on an interesting NRF2 study currently in progress. Diabetes is a huge concern to many individuals and families. According to statistics published by the American Diabetes Association  more than 25.8 million children and adults in the United States in 2010 have diabetes. That accounts for 8.3% of the population. A whopping 79 million people have pre-diabetic symptoms. In 2010, there were 1.9 million new cases of diabetes in people aged 20 years and older.

            Complications from Diabetes

            The following complications may occur as a result of diabetes.

            • Heart disease and stroke
            • High blood pressure
            • Blindness
            • Kidney disease
            • Nervous system disease (Neuropathy)
            • Amputation

            The following study is highlighted on the American Diabetes Association (ADA) website.

            Nrf2 activator to prevent diabetic cardiomyopathy

            The study is being conducted by: Cai, Lu , M.D., Ph.D. University of Louisville, Louisville, Kentucky. It focuses on both Type 1 And Type 2 Diabetes. The study started January 1, 2011 and is anticipated to end December 31, 2013.

            Background:

            Oxidative stress is associated with over 200 diseases, including diabetes. A diabetic’s heart is easily damaged from oxidative stress. Consuming antioxidants directly is not an effective enough protector of the heart. This study attempts to stimulate the body’s own production of several antioxidant genes/proteins in the heart through  a pathway known as the Nrf2 pathway. Nrf2 is the master regulator which turns on several antioxidant enzymes in the body.

            According to the website, Dr. Cai’s group showed that mice without Nrf2 are more easily damaged by diabetes than mice with higher levels of Nrf2. The group used a compound known as Dh404 as their NRF2 activator. Their hope is that results of this study will be conclusive to provide a new medication to protect the heart from diabetes. The researchers state that although this a new approach to diabetes treatment, their initial research shows it to be “a feasible project since we have shown the importance of Nrf2 in protecting a diabetic heart, and also have the compound (Dh404) to increase cardiac Nrf2 in animals.”

            To be more specific regarding protecting the heart, this project investigates the effects of NRF2 on diabetic myocardial complications (diabetic cardiomyopathy).  When the results are presented, there will be an answer to whether Nrf2 is capable of preventing diabetes-induced oxidative and nitrosative stress and the resulting progression of diabetic cardiomyopathy.

            The researchers  hope that if their findings are positive, that they might find or develop some dietary supplements to up-regulate cardiovascular levels of Nrf2. They further hope that this NRF2 up-regulation of genes and proteins in the heart will be able to prevent diabetes-induced cardiovascular diseases.

            Dr. Cai is motivated to find a cure due to the fact that many of his friends and family have been inflicted with Diabetes, including his mother in 1999 at the age of 59 years of age.

            Dr. Cai believes that diabetes (both type I and type II) will be prevented or at least delayed if an early diagnosis and treatment can be implemented as a result of these and future studies. It is his hope that hypertension, cardiomyopathy, and stroke will be prevented through the enhancement of endogenous and exogenous antioxidants.

            There are over 150 NRF2/Diabetic studies published on Pubmed.

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