The nuclear factor E2-related factor 2 and age-related macular degeneration / O fator 2 relacionado a NF-E2 e a degeneração macular relacionada à idade

ABSTRACT After the discovery of anti-vascular endothelial growth factor agents as treatment of wet age-related macular degeneration, the number of studies with the objective to understand the molecular mechanisms involved in the age-re lated macular degeneration genesis has increased. The importance of the nuclear factor e2-related factor 2 lies in its activation-derived proteins being involved in the maintenance of the redox balance and consequent prevention of degenerative macular disease. This article aims to present the characteristics of nuclear factor e2-related factor 2 and describe the main nuclear factor e2-related factor 2-activated antioxidant enzymes that contribute to the preservation of vision.

RESUMO Após a descoberta do anti fator de crescimento en dotelial vascular no tratamento da degeneração macular relacionada à idade úmida, muitas pesquisas têm sido realizadas com o intuito de elucidar os mecanismos moleculares envolvidos na gênese da degeneração macular relacionada à idade. O fator nuclear eritroide 2 relacionado ao fator 2 destaca-se pelo fato de diversas proteínas, oriundas de sua ativação, estarem envolvidas na manutenção do equilíbrio do estado redox e consequente prevenção da doença macular degenerativa. Este artigo mostra as características do fator nuclear eritroide 2 relacionado ao fator 2 e descreve as principais enzimas antioxidantes originadas da ativação que contribuem para a preservação da visão.

Protective Effect of Alcohol Extract of Phyllanthi Fructus on Silicosis Mice and Its Correlation with Nrf2/ARE Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo explore the effect and underlying mechanism of alcohol extract of Phyllanthi Fructus on silicosis mice induced by silicon dioxide （SiO2）. MethodThirty-six male Kunming mice of SPF grade were randomly divided into a blank group，a model group，high-， medium， and low-dose Phyllanthi Fructus groups （800， 400， 200 mg·kg-1），and a tetrandrine group （0.039 mg·kg-1），with six mice in each group. The silicosis model was induced by static SiO2 exposure in mice except for those in the blank group. After 28 days of administration by gavage，the lung tissues were collected and the organ coefficient was calculated. Hematoxylin-eosin（HE）staining and Masson staining were used to detect the morphology of lung tissues. The content of hydroxyproline （HYP），superoxide dismutase （SOD），malondialdehyde （MDA）， and catalase （CAT） in serum was detected by enzyme-linked immunosorbent assay （ELISA）. Western blot and Real-time polymerase chain reaction（Real-time PCR） were used to detect the protein and mRNA expression of nuclear factor E2-related factor 2 （Nrf2），heme oxygenase-1 （HO-1），NAD（P）H：quinone oxidoreductase 1 （NQO1），and Kelch-like ECH-associated protein 1 （Keap1）， respectively. ResultCompared with the blank group，the model group showed seriously damaged morphological structure of lung tissues with inflammatory cell infiltration and fibrous tissue proliferation， reduced serum content of SOD and CAT（P<0.01），increased content of HYP and MDA（P<0.01）， down-regulated protein and mRNA expression of Nrf2，HO-1， and NQO1（P<0.01），and up-regulated protein and mRNA expression of Keap1 （P<0.05，P<0.01）. Compared with the model group，the high- and medium-dose Phyllanthi Fructus groups showed significantly restored morphological structure of lung tissues with reduced collagen deposition， increased serum content of SOD and CAT（P<0.05，P<0.01），decreased content of HYP and MDA（P<0.01）， up-regulated protein and mRNA expression of Nrf2，HO-1， and NQO1 （P<0.05，P<0.01），and down-regulated protein and mRNA expression of Keap1（P<0.05，P<0.01）. ConclusionThe alcohol extract of Phyllanthi Fructus can inhibit pulmonary fibrosis in silicosis mice，and the underlying mechanism may be related to the regulation of the Nrf2/antioxidant response element （ARE） signaling pathway.

Neuroprotection of Natural Products Based on Keap1/Nrf2/ARE Signaling Pathway： A Review / 中国实验方剂学杂志

The pathological manifestations of neurodegenerative diseases， such as Alzheimer's disease， Parkinson's disease， and multiple sclerosis， are abnormal protein aggregation and accumulation， microglia activation， and mitochondrial dysfunction， which eventually lead to the gradual loss of neuronal structure or function and deteriorate over time. These pathological processes are related to the production of reactive oxygen species （ROS）， which can cause oxidative stress and damage proteins， lipids， and DNA， leading to cell and tissue injuries. The Kelch-like ECH-associated protein 1 （Keap1）/nuclear factor E2-related factor 2 （Nrf2）/antioxidant response element （ARE） signaling pathway is the main mechanism to maintain the redox balance of the body and defend against oxidative stress injury. Nrf2 activates the expression of a series of antioxidant genes related to ARE through the dissociation of Keap1 and nuclear transfer in the cytoplasm to protect the body from oxidative damage. Therefore， the discovery and study of the Keap1/Nrf2/ARE signaling pathway activator is of great significance for the prevention and treatment of neurodegenerative diseases. Because of the remarkable biological activity and slight side effects， natural products are a treasure trove for new drug research and development. Studies have shown that a variety of natural products can activate the Keap1/Nrf2/ARE signaling pathway and play a neuroprotective role. According to the structural characteristics， natural products can be divided into flavonoids， terpenoids， volatile oils， polyphenols， and phenylpropanoids. This study summarized the underlying mechanism of the Keap1/Nrf2/ARE signaling pathway in regulating diseases and reviewed the research progress on natural products based on this signaling pathway in neuroprotection to provide references for the development of clinical drugs for the prevention and treatment of neurodegenerative diseases.

Shenling Baizhusan Improves Spermatogenesis in Hyperuricemia Oligoasthenospermia Mice by Regulating Nrf2/ARE Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the effect and mechanism of Shenling Baizhusan on the treatment of oligoasthenospermia with hyperuricemia （HUA）. MethodThirty-two male Kunming （KM） mice were randomly divided into blank group （n=6）， model group （n=6）， high-dose Shenling Baizhusan group （n=7）， low-dose Shenling Baizhusan group （n=7）， and febuxostat group （n=6）. Except for the blank group， all other groups received intraperitoneal injection of potassium oxazinate suspension （600 mg·kg-1） for 7 days. After modeling， the high-dose Shenling Baizhusan group and the low-dose Shenling Baizhusan group were orally administered with 20.14 g·kg-1 and 10.07 g·kg-1 of Shenling Baizhusan， respectively. The Febuxostat group was orally administered with 0.25 g·kg-1 of Febuxostat， while the blank group and model group were orally administered with the same volume of physiological saline. Oral administration was performed once a day for 14 consecutive days， after which samples were collected. Biochemical methods were used to measure serum uric acid （UA）， superoxide dismutase （SOD） and malondialdehyde （MDA） in testicular tissue. Hematoxylin-eosin （HE） staining was used to observe the histopathological changes in testicular tissue and evaluate the spermatogenesis function. Automated sperm analyzer was used to measure sperm density and motility. Single-cell gel electrophoresis （SCGE） was used to assess sperm DNA integrity. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling （TUNEL） was used to detect testicular cell apoptosis rate. Western blot analysis was performed to measure the protein expression levels of Kelch-like ECH-associated protein 1 （Keap1）， nuclear factor E2-related factor 2 （Nrf2）， heme oxygenase-1 （HO-1）， B-cell lymphoma-2 （Bcl-2）， Bcl-2-associated X protein （Bax）， and Caspase-3 in testicular tissue. Real-time polymerase chain reaction （PCR） was conducted to evaluate the mRNA expression levels of Keap1， Nrf2， and HO-1 in testicular tissue. ResultCompared with the blank group， the model group showed elevated serum UA level （P<0.01）， decreased testicular spermatogenesis function， sperm density， and motility （P<0.01）， and increased sperm trailing rate and testicular cell apoptosis rate （P<0.01）. Compared with the model group， the high-dose Shenling Baizhusan group showed significant improvements in the above-mentioned indicators （P<0.05， P<0.01）. Additionally， the expression levels of Keap1， Bax， and Caspase-3 in testicular tissue were reduced， while the expression levels of Nrf2， HO-1， and Bcl-2 increased （P<0.05， P<0.01）. The mRNA level of Keap1 decreased （P<0.05， P<0.01）， while the mRNA levels of Nrf2 and HO-1 increased （P<0.05， P<0.01）. ConclusionShenling Baizhusan can significantly improve HUA oligoasthenospermia， and its mechanism may be related to the Nrf2/antioxidant response element （ARE） signaling pathway.

Protective Mechanism of Total Flavonoids of Lavender Against Skin Photoaging in Mice / 中国实验方剂学杂志

ObjectiveTo study the protective effect of total flavonoids of lavender on skin photoaging induced by ultraviolet B （UVB） in mice and to explore its mechanism from the perspective of nuclear factor E2-related factor 2 （Nrf2） antioxidant pathway. MethodEighty-four female KM mice were randomly divided into seven groups， namely blank group， model group， solvent group， vitamin E （0.013 g·kg-1） group， as well as low-， middle-， and high-dose （0.25， 1.25， 2.50 g·kg-1） groups of total flavonoids of lavender. The naked skin on the back of mice was irradiated with UVB for inducing optical damage. Thirty minutes before irradiation， the skin was coated with the total flavonoids of lavender. After continuous irradiation for one week， the skin moisture and elasticity on the back of mice were evaluated， and the effects of total flavonoids of lavender on histopathological changes in mouse skin were investigated by hematoxylin-eosin （HE） and Van Gieson （VG） staining. The levels of malondialdehyde （MDA）， superoxide dismutase （SOD）， total antioxidant capacity （T-AOC）， nitric oxide synthase （NOS）， and glutathione peroxidase （GSH-Px） after skin homogenization were detected by colorimetry， the inflammatory factors interleukin-1 （IL-1）， interleukin-6 （IL-6） and tumor necrosis factor-α （TNF-α） in skin tissue by enzyme-linked immunosorbent assay （ELISA）， and the mRNA expression levels of Nrf2， Kelch-like epichlorohydrin-associated protein 1 （Keap1）， BTB-CNC homology 1 （Bach1）， heme oxygenase-1 （HO-1）， quinone oxidoreductase 1 （NQO1）， and glutamate-cysteine ligase catalytic subunit （GCLC） by real-time polymerase chain reaction （Real-time PCR）. ResultCompared with the blank group， the model group exhibited significantly increased appearance score （P<0.01）， reduced skin moisture and elasticity （P<0.01）， pronounced pathological changes in the skin tissue like epidermal thickening， scabbing， small abscess， and severe injury， elevated MDA， NOS， IL-1， IL-6 and TNF-α （P<0.05， P<0.01）， lowered SOD， T-AOC， Nrf2， Keap1， NQO1 and GCLC mRNA expression （P<0.05，P<0.01）， and up-regulated Bach1 mRNA expression （P<0.01）. Compared with the model group， the total flavonoids of lavender at the low， middle， and high doses all remarkably reduced the appearance score （P<0.01）， enhanced the skin moisture and elasticity （P<0.01）， diminished the MDA， NOS， IL-1， IL-6， and TNF-α （P<0.05， P<0.01）， increased SOD， T-AOC， Nrf2， Keap1， NQO1， HO-1 and GCLC mRNA expression （P<0.05， P<0.01）， and down-regulated the expression of Bach1 mRNA （P<0.01）. ConclusionThe protective effect of the total flavonoids of lavender against skin photoaging in mice is significant， which may be related to its activation of Keap1/Nrf2/ARE signaling pathway， regulation of oxidative stress， and improvement of inflammatory response.

Protective Effect of Angelicae Sinensis Radix-Chuanxiong Rhizoma Medicated Serum Against H2O2-induced Oxidative Damage of PC12 Cells Based on Nrf2/ARE Signaling Pathway / 中国实验方剂学杂志

Objective:To investigate the protective effect and molecular mechanism of Angelicae Sinensis Radix-Chuanxiong Rhizoma medicated serum （ASRCRS） against oxidative damage of PC12 cells induced by H₂O₂. Method:Oxidative damage of PC12 cells was induced by H₂O₂<italic> in vitro</italic>， and intervention was performed in the low-， medium-， and high-dose ASRCRS groups with a final volume fraction of 15%. The cell viability was determined by methyl thiazolyl tetrazolium （MTT） assay. Cell morphology was observed by an inverted fluorescence microscope. The content of lactate dehydrogenase （LDH） and malondialdehyde （MDA）， the activity of superoxide dismutase （SOD）， and the distribution of reactive oxygen species （ROS） in the cell supernatant were detected by the kits. Cell apoptosis was detected by Annexin V-FITC/PI double staining. The protein expression levels of nuclear factor E₂-related factor 2 （Nrf2）， Kelch-like epichlorohydrin associated protein-1 （Keap1）， heme oxygenase-1 （HO-1）， and SOD1 were detected by Western blot. Result:Oxidative damage was induced by 300 μmol·L^-1 H₂O₂ for 24 hours. Compared with the normal group， the model group showed abnormal cell morphology， reduced cell viability （<italic>P</italic><0.01）， increased LDH and MDA （<italic>P</italic><0.01）， blunted SOD activity， elevated intracellular distribution of ROS， down-regulated protein expression of Nrf2， HO-1， and SOD1 （<italic>P</italic><0.05， <italic>P</italic><0.05）， and up-regulated protein expression of Keap1 （<italic>P</italic><0.01）. Compared with the model group， ASRCRS groups displayed improved cell morphology， increased cell viability， inhibited cell apoptosis， potentiated SOD activity （<italic>P</italic><0.01）， suppressed release of LDH （<italic>P</italic><0.01） and generation of ROS， decreased content of MDA （<italic>P</italic><0.01）， up-regulated protein expression of Nrf2， HO-1 and SOD1 （<italic>P</italic><0.05， <italic>P</italic><0.01）， and down-regulated protein expression of Keap1 （<italic>P</italic><0.01）. Conclusion:ASRCRS could protect PC12 cells from oxidative damage induced by H₂O₂ by up-regulating the expression of Nrf2 to activate the Nrf2/antioxidant response element （ARE） signaling pathway， enhancing the ability to resist oxidative damage， and inhibiting cell apoptosis.

Effect and Mechanism of Banxia Xiexintang on Rats with Chronic Atrophic Gastritis Based on Keap1/Nrf2/ARE Signaling Pathway / 中国实验方剂学杂志

Objective:To explore the mechanism of Banxia Xiexintang （BXXX） in preventing and treating chronic atrophic gastritis （CAG） through Kelch-like ECH-associated protein 1 （Keap1）/nuclear factor erythroid 2-related factor 2 （Nrf2）/antioxidant response element （ARE） signaling pathway. Method:SD rats were divided into a normal group （<italic>n</italic>=12） and an experimental group for CAG model induction. The model rats were then randomly divided into a model group， a vatacoenayme （VG） group （60 mg·kg^-1）， and high- （280 mg·kg^-1）， medium- （140 mg·kg^-1）， and low-dose （70 mg·kg^-1） BXXX groups. The doses in the BXXX groups were equivalent to 28， 14， and 7 g·kg^-1 crude drugs. The rats in the normal group and the model group received distilled water at an equal volume， and those in the VG group and the BXXX groups were treated correspondingly by gavage. After 12 weeks of treatment， hematoxylin-eosin （HE） staining was carried out to observe pathological changes in the gastric mucosa of CAG rats. Western blot and real-time fluorescence-based quantitative PCR was used to detect the protein and mRNA expression levels of Nrf2， glutathione S-transferase （GST）， and NAD （P）H：quinone oxidoreductase 1 （NQO1） in the gastric mucosa of CAG rats. Result:Compared with the normal group， the model group showed increased protein and mRNA expression levels of Nrf2， NQO1， and GST in the gastric mucosa of the rats （<italic>P</italic><0.05）， atrophic gastric mucosa， and even intestinal metaplasia. The protein and mRNA expression levels of Nrf2， NQO1， and GST in the VG group and the high- and medium-dose BXXX groups were lower than those in the model group （<italic>P</italic><0.05）， and gastric mucosa atrophy and intestinal metaplasia were significantly improved， especially in the high-dose BXXX group. However， the effect in the low-dose BXXX group was not significant. Conclusion:BXXX can blunt the transcriptional activity of Nrf2， shut down Nrf2 signaling pathway， and reduce the expression levels of NQO1 and GST to achieve normal oxidation-anti-oxidation balance， which may be one of its action mechanisms in the treatment of CAG.

Effect and Mechanism of Shaofu Zhuyutang on Endothelial Injury of Rats with Cold Coagulation and Blood Stasis Syndrome Based on Nrf2/ARE Signaling Pathway / 中国实验方剂学杂志

Objective:To observe the effect of Shaofu Zhuyutang on nuclear factor erythroid-2-related factor 2 （Nrf2） /antioxidant response element （ARE） signaling pathway in blood vessels by establishing the model of rats with cold coagulation and blood stasis syndrome， and to explore the protective effect and mechanism of Shaofu Zhuyutang on vascular endothelial injury. Method:The 50 SPF rats were randomly divided into high dose group （4.8 g·kg-1）， middle dose group （2.4 g·kg-1）， low dose group （1.2 g·kg-1）， model group and normal group （ten of each group）. The rat model of cold coagulation and blood stasis syndrome was established by subcutaneous injection of epinephrine hydrochloride combined with ice bath. At the same time of modeling， the drug was administered by gavage. After 28 days of continuous administration， the hemorheology indexes were detected by automatic hemorheology instrument. Levels of nitric oxide （NO）， endothelin （ET）-1， superoxide dismutase （SOD）， glutathione （GSH-Px）， intercellular adhesion molecule-1（ICAM-1）， vascular cell adhesion molecule-1（VCAM-1）， von Willebrand factor （vWF） in serum were determined by ELISA. Hematoxylin and eosin （HE） staining was used to observe the endothelial injury of vascular tissue of thoracic aorta. The protein expression of Nrf2 and HO-1 in vascular tissue of thoracic aorta was detected by Western blot. Real-time fluorescence quantitative polymerase chain reaction（Real-time PCR）was used to observe the expression of Nrf2 and heme oxygenase-1 （HO-1） mRNA in vascular tissue of thoracic aorta. Result:Compared with the blank group， model group rats whole blood viscosity and plasma viscosity were significantly increased （P<0.05，P<0.01）， vWF， ICAM 1， VCAM 1 content increased significantly （P<0.01）， NO， SOD， gsh-px levels decreased significantly （P<0.01）， significantly increased the content of ET-1（P<0.01）， thoracic aorta vascular tissue Nrf2， HO-1 mRNA expression was significantly increased （P<0.01）， Nrf2 protein expression in the cell nucleus increased significantly （P<0.05）， The protein expression level of Nrf2 in cytoplasm was significantly decreased （P<0.05）， while the protein expression level of HO-1 was significantly increased （P<0.01）. Compared with model group， the whole blood viscosity （high and middle cut）， plasma viscosity， were significantly reduced in high and meduim-dose Shaofu Zhuyutang groups（P<0.05，P<0.01）. The levels of vWF， ICAM-1， VCAM-1 and ET-1 in serum were significantly reduced （P<0.05，P<0.01）， NO， SOD and GSH-Px increased significantly （P<0.05，P<0.01）. The pathological changes such as hyperplasia， swelling and shedding of endothelial cells of thoracic aorta， rupture of internal elastic membrane and disorder of smooth muscle arrangement were improved. The expression levels of Nrf2， HO-1 protein and gene were significantly increased in vascular tissue of thoracic aorta （P<0.01）. Conclusion:Shaofu Zhuyutang has a protective effect on vascular endothelial injury in rats with cold coagulation and blood stasis syndrome. The mechanism of action is related to the activation of Nrf2/ARE signaling pathway， which leading to the increased expression of antioxidant enzymes and decreased the expression of adhesion factors.

SIRT6 as a key event linking P53 and NRF2 counteracts APAP-induced hepatotoxicity through inhibiting oxidative stress and promoting hepatocyte proliferation

Acetaminophen (APAP) overdose is the leading cause of drug-induced liver injury, and its prognosis depends on the balance between hepatocyte death and regeneration. Sirtuin 6 (SIRT6) has been reported to protect against oxidative stress-associated DNA damage. But whether SIRT6 regulates APAP-induced hepatotoxicity remains unclear. In this study, the protein expression of nuclear and total SIRT6 was up-regulated in mice liver at 6 and 48 h following APAP treatment, respectively.

Recommendations for the use of the acetaminophen hepatotoxicity model for mechanistic studies and how to avoid common pitfalls

Acetaminophen (APAP) is a widely used analgesic and antipyretic drug, which is safe at therapeutic doses but can cause severe liver injury and even liver failure after overdoses. The mouse model of APAP hepatotoxicity recapitulates closely the human pathophysiology. As a result, this clinically relevant model is frequently used to study mechanisms of drug-induced liver injury and even more so to test potential therapeutic interventions. However, the complexity of the model requires a thorough understanding of the pathophysiology to obtain valid results and mechanistic information that is translatable to the clinic. However, many studies using this model are flawed, which jeopardizes the scientific and clinical relevance. The purpose of this review is to provide a framework of the model where mechanistically sound and clinically relevant data can be obtained. The discussion provides insight into the injury mechanisms and how to study it including the critical roles of drug metabolism, mitochondrial dysfunction, necrotic cell death, autophagy and the sterile inflammatory response. In addition, the most frequently made mistakes when using this model are discussed. Thus, considering these recommendations when studying APAP hepatotoxicity will facilitate the discovery of more clinically relevant interventions.

Fish biomarker responses to perturbation by drought in streams

Drought can be viewd as a perturbation in running waters and fish are often trapped in isolated pools, where deterioration of water quality may be stressful. We investigated how this extreme condition influences response of oxidative stress biomarkers. The response of the characid Astyanax elachylepis was assessed during the dry and rainy seasons in intermittent and perennial (control) sites in streams from Brazilian savannah (Cerrado). We predicted that the biomarkers would be enhanced in the dry season in intermittent streams only due the environmentally harsh conditions in the few isolated pools that remain filled with water. As predicted, fish from the intermittent stream in the dry season presented higher gill MDA values, indicating greater stress. In the liver, MDA values were higher in the dry season for both intermittent and perennial streams, suggesting a generalized seasonal response. As expected, some antioxidant response enzymes changed in the intermittent sites during the dry season. Therefore, oxidative stress biomarkers vary seasonally, with greater increase in intermittent sites. These evidences contribute for the understanding of the spatio-temporal variation of the fish responses and fish resistance to perturbations by drought in tropical environments.(AU)

A seca pode ser vista como uma perturbação em ambientes aquáticos lóticos e, em alguns casos, os peixes podem ser aprisionados em trechos lênticos (poços), onde a perda da qualidade da água pode causar estresse. Investigamos como esta condição extrema influencia biomarcadores bioquímicos de estresse oxidativo. Para isso, a resposta do caracídeo Astyanax elachylepis foi avaliada durante as estações seca e chuvosa em trechos intermitentes e perenes (controle) de riachos da savana brasileira (Cerrado). Predizemos que os biomarcadores seriam aumentados somente em peixes dos trechos intermitentes durante a estação seca, devido as condições restritivas dos poucos poços isolados que contém água. Como predito, os peixes do riacho intermitente apresentaram altos valores de MDA nas brânquias durante a estação seca, indicando maior estresse oxidativo. No fígado, os valores de MDA foram maiores na estação seca em ambos riachos, intermitente e perene, sugerindo uma resposta sazonal generalizada. Como esperado, algumas enzimas antioxidantes foram alteradas em peixes de trechos intermitentes durante a estação seca. Portanto, os biomarcadores de estresse oxidativo variam sazonalmente e essa variação é maior em trechos intermitentes. Essas evidências contribuem para a compreensão da variação espaço-temporal da resposta dos peixes e da sua resistência às perturbações por seca em ambientes tropicais.(AU)

Effect of vitexin on Nrf2/ARE pathway in alleviating oxidative stress in rats with acute cerebral ischemia-reperfusion / 中草药

Objective: To investigate the effect of vitexin on oxidative stress in rats with acute cerebral ischemia-reperfusion by regulating the pathway of nuclear factor E2-related factor 2 (Nrf2)/antioxidant response element (ARE). Methods: A total of 54 SD rats were randomly divided into Sham group, model group, positive control (edaravone 0.56 mg/kg) group and vitexin low, medium, and high dose (10, 20, 40 mg/kg) groups. The rat models with acute cerebral ischemia were established except the Sham group. After reperfusion, rats in Sham group and model group were received ip saline. The edaravone group and vitexin groups were administered according to the corresponding dose, once every 8 h for a total of three times. The neurobehavioral scores of rats before and after intervention were compared. HE staining was used to detect the pathological changes of cerebral cortex. The levels of MDA, NO, SOD, and GSH in cerebral cortex of rats were detected by the kit. The mRNA and protein expression levels of Nrf2/ARE pathway related gene in rat cerebral cortex were detected by real-time fluorescent quantitative PCR (qRT-PCR) and Western blotting. Results: Before and after intervention, there was no significant change in the neurobehavioral score of rats in the Sham group, the model group was higher than before intervention (P < 0.01), the edaravone group and the vitexin groups were lower than before intervention (P < 0.01), and there was a significant difference in the neurobehavioral score between the groups after intervention (P < 0.01). In the Sham group, the distribution of nerve cells was uniform and dense, and the morphology of cell body and nucleus was normal. In the model group, edaravone group and vitexin group, the arrangement of brain tissue was disordered and loose, in which liquefying necrosis and disappearance of cell structure were observed in the model group; in the low-dose group, the arrangement of cells was seriously disordered and loose. In the vitexin medium dose group and edaravone group, the area of liquefying necrosis was small, and most of the cells were normal; In the vitexin high dose group, only a few liquefying necrosis were found, the cell structure was basically normal, and the cell arrangement was slightly disordered. Compared with the Sham group, the levels of MDA and NO in the cerebral cortex of the model group were significantly increased (P < 0.01), the levels of SOD and GSH were significantly reduced (P < 0.01), and the expression levels of Nrf2 and γ-GCS mRNA were significantly increased (P < 0.01), the expression of cytoplasmic Nrf2 and γ-GCS proteins were significantly increased (P < 0.01), and the expression levels of nuclear Nrf2 and HO-1 proteins were significantly decreased (P < 0.01). Compared with the model group, the levels of MDA and NO in the cerebral cortex of rats in the edaravone group and low, medium and high dose groups of vitexin were significantly reduced (P < 0.01), and the levels of SOD and GSH were significantly increased (P < 0.01), Nrf2 and γ-GCS mRNA expression levels were significantly reduced (P < 0.01), cytoplasmic Nrf2, γ-GCS protein expressions were significantly reduced (P < 0.01), and nuclear Nrf2 and HO-1 protein expression levels were significantly increased (P < 0.01). And the levels of MDA, NO, SOD, GSH and Nrf2, γ-GCS, HO-1 mRNA and protein expression in rat cerebral cortex in each dose group were dose-dependent, with significant differences between groups (P < 0.01). Conclusion: Vitexin can alleviate oxidative stress in rats with acute cerebral ischemia-reperfusion. It is speculated that it is related to the regulation of Nrf2/ARE signaling pathway, the up-regulation of Nrf2 gene and protein expression, the promotion of its movement from cytoplasm to nucleus, the up-regulation of HO-1 expression, the inhibition of γ-GCS expression, and the enhancement of the body’s ability to response to oxidative stress.

Efectividad de los suplementos antioxidantes en la mejoría del desempeño físico atlético. Artículo de revisión / Effectiveness of antioxidant supplements in the improvement of athletic physical performance: Review article

Introducción: En la actualidad se ha incrementado el uso de antioxidantes en el ámbito deportivo, sin embargo, no existe evidencia concluyente del efecto de estas sustancias en la mejora del desempeño físico de los atletas. Objetivo: Determinar la efectividad del uso de suplementos antioxidantes en la mejoría del desempeño físico atlético. Material y Métodos: Se realizó una revisión bibliográfica en bases de datos en línea como Pubmed, Scopus, la Web of Knowledge y el buscador google academic. Se incluyeron solo trabajos originales de estudios doble ciego relacionados con la intervención de un suplemento antioxidante. El periodo de revisión fue del 2009 a diciembre del 2017. Desarrollo: Se identificaron un total de 1053 artículos de los cuales 33 cumplieron con los criterios de inclusión de la revisión. De acuerdo con el tipo de suplemento, 2 correspondieron a vitaminas, 9 a polifenoles, 11 comerciales y los 9 restantes diversos. La antigüedad de los artículos analizados fue de 4,8 ± 2,4 años, en cuanto a la obsolescencia, determinado por el semiperiodo de Burton y Kleber y el índice de Price, fue 5,5 y 61,0 por ciento respectivamente. Conclusiones: Hasta el momento no existe evidencia sólida de que la ingesta de suplementos antioxidantes mejore el desempeño físico atlético. Son pocos los resultados positivos en alguna de las variables evaluadas, por tal motivo se requiere de mayor evidencia para poder dilucidar el efecto de los suplementos antioxidantes(AU)

Introduction: At present, the use of antioxidants in the sports field has increased. However, there is no conclusive evidence of the effect of these substances in improving the physical performance of athletes. Objective: To determine the effectiveness of antioxidant supplements in the improvement of athletic physical performance. Material and Methods: A bibliographic review was carried out through the search on online databases such as Pubmed, Scopus, the Web of Knowledge and Google Scholar search engine. Only original double-blind studies related to the intervention of an antioxidant supplement were included. The review period was from 2009 to December 2017. Development: A total of 1053 articles were identified, of which 33 met the inclusion criteria for the review. Regarding the type of supplement, 2 of them corresponded to vitamins, 9 to polyphenols, 11 to commercials, and the remaining 9 ones to several types. The historic period of the articles analyzed was 4.8 ± 2.4 years in terms of obsolescence, which was determined by the Burton and Kleber half-period and the Price index (5.5 and 61.0 percent respectively). Conclusions: To date, there is no solid evidence that the intake of antioxidant supplements improves physical athletic performance. There are few positive results in some of the evaluated variables; for this reason, more evidence is required to elucidate the effect of antioxidant supplements(AU)

LBP reduces theinflammatory injuryof kidney in septic rat and regulates the Keap1-Nrf2∕ARE signaling pathway

Abstract Purpose: To investigate the influence of lycium barbarum polysaccharides (LBP), a functional derivative from lycium barbarum, on septic kidney injury. Methods: The SD male rats were randomly divided into 8 groups. The concentration of IL-1β, IL-6, IL-8, TNF-α, NF-κB and ROS, in kidney cortex homogenates after 12 h treatments were determined by enzyme-linked immunosorbent assay and ROS test kit, respectively. Morphology observation of kidney tissue was conducted with HE staining. The mRNA and protein expression levels of Nrf2, HO-1, NQO1, NF-κB, and Keap1 in kidney tissues were determined by qRT-PCR and Western blot, respectively. Results: LPS treatment significantly increased the oxidative stress. After LBP treatment, the ROS content reduced significantly in a dose-depend manner. However, the levels of HO-1, NQO1 and Nrf2 as molecular elements that respond to oxidative stress were further increased. Also, administration of LBP increased the levels of NF-κB and Keap1, and decreased the levels of Nrf2 in the Keap 1-Nrf2∕ARE signaling pathway. By administrating the brusatol, the inhibition of Nrf2 enhanced the expression of NF-κB, inhibits the antioxidant responses, and further reverse the protective effect of LBP on the LPS induced septic kidney injury. Conclusion: Lycium barbarum polysaccharides can reduce inflammation and activate the antioxidant responses via regulating the level of pro-inflammatory cytokines and the Keap1-Nrf2/ARE signaling pathway.

Effect of Trillin on Oxidative Stress and Nuclear Factor E2-related Factor 2/Antioxidant Response Element Pathway in Rats after Spinal Cord Injury / 中国康复理论与实践

Objective:To explore the effect of trillin on oxidative stress response and nuclear factor E2-related factor 2/antioxidant response element (Nrf2/ARE) pathway in rats after spinal cord injury (SCI). Methods:A total of 108 male Sprague-Dawley rats were randomly divided into sham group (n = 36), model group (n = 36) and trillin group (n = 36), each group was divided into one day, three days and seven days subgroups, with twelve rats in each subgroup. The SCI model was established by modified Allen's heavy strike method in the model group and the trillin group, but no obvious injury in the sham group. The trillin group was given trillin 200 mg/kg every day, and the same amount of normal saline was given in the sham group and model group, twice a day. BBB score was performed one day, three days and seven days after modeling. Morphological changes were tested by Nissl's staining, and the changes of malonaldehyde (MDA) content and superoxide dismutase (SOD) activity were detected by ELISA seven days after modeling. The expression of Nrf2, Kelch like ECH associated protein 1 (Keap1), NAD(P)H quinone oxidoreductase (NQO1) and haemoxygenase 1 (HO-1) were detected by Western blotting one day, three days and seven days after modeling. Results:Compared with the model group, BBB scores increased (P < 0.05); the structure of spinal cord was more complete and the number of Nissl bodies increased; SOD activity increased (P < 0.05) and MDA content decreased (P < 0.05); the expression of Nrf2, Keap1, NQO1 and HO-1 increased (P < 0.05) in the trillin group. Conclusion:Trillin may play a protective role in spinal cord injury by inhibiting oxidative stress response and improving the motor function.

Effect of tea polyphenols on diabetic nephropathy mice by regulating Nrf-2/ARE signaling pathway / 国际生物医学工程杂志

Objective To investigate the effects of tea-polyphenols on diabetic nephropathy (DN) mice by regulating nuclear factor E2-related factor 2/antioxidant response element (Nrf-2/ARE) signaling pathway. Methods A total of ten male 9-week-old normal (db/m) mice were randomly and equally divided into blank control group and tea-polyphenol control group, and ten male 9-week-old homologous type 2 diabetes (db/db) mice were randomly divided into model group and tea polyphenol treatment group. The animals in the tea-polyphenol control group and the treatment group were given 50 mg/(kg·d) tea-polyphenols by oral gavage, and the animals in the blank control group and model group were given same volume of double distilled water. The administration was once a day for 8 weeks. The blood glucose and 24-hour urine protein quantization (24 h-UP) were measured and recorded at 0, 4, and 8 weeks. After 8 weeks of the treatment, the mice were sacrificed. The intraocular blood stasis samples were collected for renal function indicators (serum creatinine and urea nitrogen), and kidney tissue samples were also collected for the tests of superoxide dismutase (SOD), reactive oxygen species, and malondialdehyde. Periodic acid Schiff reaction (PAS) staining was used to observe glomerular injury and scored. Western blot was used to detect the expression of Nrf-2 and hemeoxygenase-1 (HO-1) protein. Results Compared with the blank control group, the blood glucose and 24 h-UP of the mice in the model group and the tea-polyphenol treatment group increased after 4 and 8 weeks of the treatment (all P<0.01). Compared with the blank control group, after 8 weeks of the treatment, the serum creatinine and blood urea nitrogen of the model group and the tea-polyphenol treatment group increased (all P<0.01), the content of SOD in the renal tissue decreased (all P<0.01), the content of active oxygen and malondialdehyde, the relative expression of Nrf-2 and HO-1 protein increased (all P<0.01), and the glomerular injury aggravated (all P<0.01). However, there were no significant differences in all the indexes between the tea-polyphenol control group and the blank control group (all P>0.05). Conclusions Renal tissue of DN mice will undergo significant oxidative stress injury. Tea-polyphenols may reduce the oxidative stress injury in DN mice by regulating the Nrf-2/ARE signaling pathway, and play a protective role in the kidney.

The effects of astragalus polysaccharides on insulin resistance and Nrf2-ARE pathway in gestational diabetic rats / 中国医师杂志

Objective@#To investigate the effects of astragalus polysaccharides (APS) on insulin resistance and nuclear factor-related factor 2 (Nrf2) -antioxidant response element (ARE) pathway in gestational diabetic rats.@*Methods@#Pregnant Sprague Dawley (SD) rats were divided into normal pregnancy group (control group), model group [gestational diabetes mellitus (GDM) group], low-dose astragalus polysaccharide group (APS-L group), middle-dose astragalus polysaccharide group (APS-M group), high-dose astragalus polysaccharide group (APS-H group), pioglitazone group (Pio group). GDM rat model was established by intraperitoneal injection of streptozotocin (STZ). The levels of fasting blood glucose (FBG), fasting insulin (FINS), adiponectin (APN), tumor necrosis factor-α (TNF-α), Leptin, malondialdehyde (MDA), and superoxde dismutase (SOD) were measured before delivery and 20 days after pregnancy, then the insulin resistance index was calculated; histopathological changes of pancreas were observed by hematoxylin-eosin(HE) staining; the expressions of Nrf2, heme oxygenase-1 (HO-1), and γ-glutamyl cysteine synthase (γ-GCS)mRNAs were detected by real-time fluorescence quantitative polymerase chain reaction (qRT-PCR); Western blot was used to detect the expressions of Nrf2, HO-1, and γ-GCS proteins in pancreatic tissues.@*Results@#Compared with the control group, the levels of APN and SOD in GDM group were significantly lower (P<0.05); the levels of APN and SOD increased significantly after APS treatment, but there was no significant difference between APS-H group and Pio group; compared with the control group, the levels of TNF-α, Leptin, and MDA in the GDM group increased significantly (P<0.05); after APS treatment, the levels of TNF-α, Leptin, and MDA were significantly decreased (P<0.05), and with the increase of APS concentration, the effect of reduction was obvious, but there was no significant difference between APS-H group and Pio group; compared with the control group, the levels of FBG, FINS, insulin secretion index (IS), and insulin resistance index (IRI) in GDM group were significantly higher (P<0.05); compared with the GDM group, the levels of FBG, FINS, IS, and IRI in APS group were significantly lower, and with the increase of APS concentration, the effect of reduction was obvious, but there was no significant difference between APS-H group and Pio group; compared with the control group, the insulin sensitivity index (ISI) level in GDM group was significantly lower (P<0.05), while the level of ISI in APS group was significantly higher when treated with APS (P<0.05); the results of HE staining showed that the islet cells in the control group were regular round or oval with clear boundary; in the GDM group, the number of islets decreased significantly, while the islets atrophied without obvious boundary; after APS treatment, the number of islets increased, and the pathological damage was significantly reduced, the islet cells in Pio group showed a clear boundary after treatment; qRT-PCR showed that the expressions of Nrf2, HO-1, and γ-GCS in GDM group were significantly higher than those in control group (P<0.05), after APS treatment, the expression levels of Nrf2, HO-1, and γ-GCS decreased significantly (P<0.05), but there was no significant difference between APS-H group with Pio group; Western Blot results showed that the expressions of Nrf2, HO-1, and γ-GCS in GDM group were significantly higher than those in control group (P<0.05), after APS treatment, the levels of Nrf2, HO-1, and γ-GCS in APS group and Pio group were significantly lower than those in GDM group, but there was no significant difference between APS-H group with Pio group.@*Conclusions@#Astragalus polysaccharide can reduce insulin resistance in diabetic rats, which may play the role through Nrf2-ARE pathway.

The effects of astragalus polysaccharides on insulin resistance and Nrf2-ARE pathway in gestational diabetic rats / 中国医师杂志

Objective To investigate the effects of astragalus polysaccharides (APS) on insulin resistance and nuclear factor-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway in gestational diabetic rats.Methods Pregnant Sprague Dawley (SD) rats were divided into normal pregnancy group (control group),model group [gestational diabetes mellitus (GDM) group],low-dose astragalus polysaccharide group (APS-L group),middle-dose astragalus polysaccharide group (APS-M group),high-dose astragalus polysaccharide group (APS-H group),pioglitazone group (Pio group).GDM rat model was established by intraperitoneal injection of streptozotocin (STZ).The levels of fasting blood glucose (FBG),fasting insulin (FINS),adiponectin (APN),tumor necrosis factor-α (TNF-α),Leptin,malondialdehyde (MDA),and superoxde dismutase (SOD) were measured before delivery and 20 days after pregnancy,then the insulin resistance index was calculated;histopathological changes of pancreas were observed by hematoxylin-eosin(HE) staining;the expressions of Nrf2,heme oxygenase-1 (HO-1),and γ-glutamyl cysteine synthase (γ-GCS)mRNAs were detected by real-time fluorescence quantitative polymerase chain reaction (qRT-PCR);Western blot was used to detect the expressions of Nrf2,HO-1,and γ-GCS proteins in pancreatic tissues.Results Compared with the control group,the levels of APN and SOD in GDM group were significantly lower (P ＜ 0.05);the levels of APN and SOD increased significantly after APS treatment,but there was no significant difference between APS-H group and Pio group;compared with the control group,the levels of TNF-α,Leptin,and MDA in the GDM group increased significantly (P ＜ 0.05);after APS treatment,the levels of TNF-α,Leptin,and MDA were significantly decreased (P ＜ 0.05),and with the increase of APS concentration,the effect of reduction was obvious,but there was no significant difference between APS-H group and Pio group;compared with the control group,the levels of FBG,FINS,insulin secretion index (IS),and insulin resistance index (IRI) in GDM group were significantly higher (P ＜ 0.05);compared with the GDM group,the levels of FBG,FINS,IS,and IRI in APS group were significantly lower,and with the increase of APS concentration,the effect of reduction was obvious,but there was no significant difference between APS-H group and Pio group;compared with the control group,the insulin sensitivity index (ISI) level in GDM group was significantly lower (P ＜0.05),while the level of ISI in APS group was significantly higher when treated with APS (P ＜ 0.05);the results of HE staining showed that the islet cells in the control group were regular round or oval with clear boundary;in the GDM group,the number of islets decreased significantly,while the islets atrophied without obvious boundary;after APS treatment,the number of islets increased,and the pathological damage was significantly reduced,the islet cells in Pio group showed a clear boundary after treatment;qRT-PCR showed that the expressions of Nrf2,HO-1,and γ-GCS in GDM group were significantly higher than those in control group (P ＜ 0.05),after APS treatment,the expression levels of Nrf2,HO-1,and γ-GCS decreased significantly (P ＜ 0.05),but there was no significant difference between APS-H group with Pio group;Western Blot results showed that the expressions of Nrf2,HO-1,and γ-GCS in GDM group were significantly higher than those in control group (P ＜ 0.05),after APS treatment,the levels of Nrf2,HO-1,and γ-GCS in APS group and Pio group were significantly lower than those in GDM group,but there was no significant difference between APS-H group with Pio group.Conclusions Astragalus polysaccharide can reduce insulin resistance in diabetic rats,which may play the role through Nrf2-ARE pathway.

4′-O-β-D-Glucosyl-5-O-Methylvisamminol Attenuates Pro-Inflammatory Responses and Protects against Oxidative Damages

We attempted to examine anti-inflammatory and anti-oxidant effects of 4′-O-β-D-glucosyl-5-O-methylvisamminol (GOMV), the first epigenetic inhibitor of histone phosphorylation at Ser10. While GOMV did not affect the viability of murine macrophage RAW 264.7 cells, it significantly suppressed lipopolysaccharide (LPS)-induced generation of prostaglandin E₂ (PGE₂) and nitric oxide (NO) through transcriptional inhibition of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). GOMV also scavenged free radicals in vitro, increased NF-E2-related factor 2 (NRF2), and activated antioxidant response element (ARE), thereby resulting in the induction of phase II cytoprotective enzymes in human keratinocyte HaCaT cells. Finally, GOMV significantly protected HaCaT cells against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced oxidative intracellular damages. Together, our results illustrate that GOMV possesses anti-inflammatory and anti-oxidant activity.

Progress in Nrf2/ARE signaling pathway and drug-resistance of tumor / 肿瘤

Nuclear factor E2-related factor 2 (Nrf2), an important transcription factor, is able to regulate Nrf2/antioxidant response element (ARE) signaling pathway, including the expressions of a series of cytoprotective proteins such as heme oxygenase-1 (HO-1), glutathione-S -transferase (GST) and quinine oxidoreductase 1 (NQO1), so as to maintain redox homeostasis and play a significant role in the prevention of cancer. However, the recent studies show that Nrf2 has another side. Nrf2 may promote the occurrence and development of tumors, and lead to drug resistance of tumor to chemotherapy, resulting in tremendous difficulties to the clinical treatment of tumors. Therefore, Nrf2/ARE signaling pathway is regarded as a breakthrough in overcoming drug resistance. This review summarizes the basic features and functions of Nrf2/ ARE signaling pathway, the dual functions of Nrf2, and the relationship between Nrf2 and multidrug resistance of tumors, all of which should facilitate the development of new strategies to improve chemotherapeutic efficacy.