Emerging trends and hotspots of Nuclear factor erythroid 2-related factor 2 in nervous system diseases

BACKGROUND The Nuclear factor erythroid 2-related factor 2(NRF2)transcription factor has attracted much attention in the context of neurological diseases.However,none of the studies have systematically clarified this field's research hotspots and evolution rules.AIM To investigate the research hotspots,evolution patterns,and future research trends in this field in recent years.METHODS We conducted a comprehensive literature search in the Web of Science Core Collection database using the following methods:(((((TS=(NFE2 L2))OR TS=(Nfe2 L2 protein,mouse))OR TS=(NF-E2-Related Factor 2))OR TS=(NRF2))OR TS=(NFE2L2))OR TS=(Nuclear factor erythroid2-related factor 2)AND(((((((TS=(neurological diseases))OR TS=(neurological disorder))OR TS=(brain disorder))OR TS=(brain injury))OR TS=(central nervous system disease))OR TS=(CNS disease))OR TS=(central nervous system disorder))OR TS=(CNS disorder)AND Language=English from 2010 to 2022.There are just two forms of literature available:Articles and reviews.Data were processed with the software Cite-Space(version 6.1.R6).RESULTS We analyzed 1884 articles from 200 schools in 72 countries/regions.Since 2015,the number of publications in this field has increased rapidly.China has the largest number of publications,but the articles published in the United States have better centrality and H-index.Among the top ten authors with the most published papers,five of them are from China,and the author with the most published papers is Wang Handong.The institution with the most articles was Nanjing University.To their credit,three of the top 10 most cited articles were written by Chinese scholars.The keyword co-occurrence map showed that"oxidative stress","NRF2","activation","expression"and"brain"were the five most frequently used keywords.CONCLUSION Research on the role of NRF2 in neurological diseases continues unabated.Researchers in developed countries published more influential papers,while Chinese scholars provided the largest number of articles.There have been numerous studies on the mechanism of NRF2 transcription factor in neurological diseases.NRF2 is also emerging as a potentially effective target for the treatment of neurological diseases.However,despite decades of research,our knowledge of NRF2 transcription factor in nervous system diseases is still limited.Further studies are needed in the future.

Nuclear factor erythroid 2-related factor 2-mediated signaling and metabolic associated fatty liver disease

Oxidative stress is a key driver in the development and progression of several diseases,including metabolic associated fatty liver disease(MAFLD).This condition includes a wide spectrum of pathological injuries,extending from simple steatosis to inflammation,fibrosis,cirrhosis,and hepatocellular carcinoma.Excessive buildup of lipids in the liver is strictly related to oxidative stress in MAFLD,progressing to liver fibrosis and cirrhosis.The nuclear factor erythroid 2-related factor 2(NRF2)is a master regulator of redox homeostasis.NRF2 plays an important role for cellular protection by inducing the expression of genes related to antioxidant,anti-inflammatory,and cytoprotective response.Consistent evidence demonstrates that NRF2 is involved in every step of MAFLD development,from simple steatosis to inflammation,advanced fibrosis,and initiation/progression of hepatocellular carcinoma.NRF2 activators regulate lipid metabolism and oxidative stress alleviating the fatty liver disease by inducing the expression of cytoprotective genes.Thus,modulating NRF2 activation is crucial not only in understanding specific mechanisms underlying MAFLD progression but also to characterize effective therapeutic strategies.This review outlined the current knowledge on the effects of NRF2 pathway,modulators,and mechanisms involved in the therapeutic implications of liver steatosis,inflammation,and fibrosis in MAFLD.

Neuroprotective effects of salidroside on focal cerebral ischemia/reperfusion injury involve the nuclear erythroid 2-related factor 2 pathway

Salidroside,the main active ingredient extracted from Rhodiola crenulata,has been shown to be neuroprotective in ischemic cerebral injury,but the underlying mechanism for this neuroprotection is poorly understood.In the current study,the neuroprotective effect of salidroside on cerebral ischemia-induced oxidative stress and the role of the nuclear factor erythroid 2-related factor 2（Nrf2）pathway was investigated in a rat model of middle cerebral artery occlusion.Salidroside（30 mg/kg）reduced infarct size,improved neurological function and histological changes,increased activity of superoxide dismutase and glutathione-S-transferase,and reduced malon-dialdehyde levels after cerebral ischemia and reperfusion.Furthermore,salidroside apparently increased Nrf2 and heme oxygenase-1 expression.These results suggest that salidroside exerts its neuroprotective effect against cerebral ischemia through anti-oxidant mechanisms and that activation of the Nrf2 pathway is involved.The Nrf2/antioxidant response element pathway may become a new therapeutic target for the treatment of ischemic stroke.

Interplay between nuclear factor erythroid 2-related factor 2 and inflammatory mediators in COVID-19-related liver injury

Coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2 is a global pandemic and poses a major threat to human health worldwide.In addition to respiratory symptoms,COVID-19 is usually accompanied by systemic inflammation and liver damage in moderate and severe cases.Nuclear factor erythroid 2-related factor 2(NRF2)is a transcription factor that regulates the expression of antioxidant proteins,participating in COVID-19-mediated inflammation and liver injury.Here,we show the novel reciprocal regulation between NRF2 and inflammatory mediators associated with COVID-19-related liver injury.Additionally,we describe some mechanisms and treatment strategies.

Keap1-nuclear factor rythroid 2-related factor 2 inhibitor NXPZ ameliorates Aβ1-42-induced cognitive dysfunction in mice

OBJECTIVE Nuclear factor erythroid 2-related factor 2(Nrf2) is found to be ubiquitiously expressed in many tissues,and works as the key regulator against oxidative stress damage in cells and organs,which makes Nrf2 a widely concerned drug target.Recent research has identified that Nrf2 is involved in the pathology of Alzheimer disease(AD),whereas the mechanism is unknown.The purpose of this study is to figure out the role of Nrf2 in the pathologic process of AD through Nrf2-Keap1-ARE pathway and the effects of Keap1-Nrf2 inhibitor in AD mice models.METHODS Amyloid β^(1-42)(Aβ^(1-42))was injected into the bilateral hippocampus to induce the cognitive dysfunction in eight-week old male mice.The mice were treated with Keap1-Nrf2 inhibitor NXPZ of three doses as well as donepezil as a positive control by intragastric administration one time a day for one week.Several behavior tests were used to analyze the mice learning and memory ability.Additionally,we detected Nrf2 and Aβ in the plasma in mice with ELISA kits,as well as some factors related to oxidative stress in the hippocampus and cortex.The expression levels of Nrf2,Keap1,Tau and p-Tau were measured in the murine brain tissue with Western blotting.SH-SY5 Y cells were studied as an in vitro model to further clarify the mechanism.RESULTS The treatment of NXPZ ameliorated learning and memory dysfunction in AD mice in a dose-dependent manner,and the high dose group recovered better than the positive drug group.The plasma Nrf2 level was increased in a dose-dependent manner in the treatment groups;however,the plasma Aβ was decreased.What′ s more,superoxide dismutase(SOD) and glutathione reductase(GSSH) in the hippocampus and cortex were increased in the treatment group,while the malondialdehyde(MDA) was decreased,meaning that NXPZ treatment promoted expression of the anti-oxidative factors and inhibited the expression of the oxidative factors in the down-stream.Western blotting analysis of hippocampus and cortex showed up-regulated Nrf2,decreased Keap1 and decreased p-Tau in NXPZ treatment mice.In ex vivo experiments,when SH-SY5 Y cells were treated with Aβ,Nrf2 in the cytoplasm was increased,as well as the expression Nrf2 in the nuclear was decreased.The treatment of NXPZ increased nuclear Nrf2,decreased cytoplasm Nrf2,and decreased the expression of p-Tau.CONCLUSION Nrf2 has an important role in neuron function.Nrf2 activation by selective Keap1-Nrf2 inhibitor NXPZ may contribute to improve cognitive function in AD mice.The mechanism may be related to increased generation and release of Nrf2 induced by more disaggregation with Keap1,leading to more expression of anti-oxidative molecules to protect the damage caused by Aβ.These results indicates that Nrf2 may be a novel therapeutic target of AD and Keap1-Nrf2 inhibitor may be a novel medication for protecting the loss of learning and memory ability.

High glucose reduces Nrf2-dependent cRAGE release and enhances inflammasome-dependent IL-1βproduction in monocytes:the modulatory effects of EGCG

Soluble receptor for advanced glycation end products(sRAGE)acts as a decoy sequestering of RAGE ligands,thus preventing the activation of the ligand-RAGE axis linking human diseases.However,the molecular mechanisms underlying sRAGE remain unclear.In this study,THP-1 monocytes were cultured in normal glucose(NG,5.5 mmol/L)and high glucose(HG,15 mmol/L)to investigate the effects of diabetesrelevant glucose concentrations on sRAGE and interleukin-1β(IL-1β)secretion.The modulatory effects of epigallocatechin gallate(EGCG)in response to HG challenge were also evaluated.HG enhanced intracellular reactive oxygen species(ROS)generation and RAGE expression.The secretion of sRAGE,including esRAGE and cRAGE,was reduced under HG conditions,together with the downregulation of a disintegrin and metallopeptidase 10(ADAM10)and nuclear factor erythroid 2-related factor 2(Nrf2)nuclear translocation.Mechanistically,the HG effects were counteracted by siRAGE and exacerbated by siNrf2.Chromatin immunoprecipitation results showed that Nrf2 binding to the ADAM10 promoter and HG interfered with this binding.Our data reinforce the notion that RAGE and Nrf2 might be sRAGE-regulating factors.Under HG conditions,the treatment of EGCG reduced ROS generation and RAGE activation.EGCG-stimulated cRAGE release was likely caused by the upregulation of the Nrf2-ADAM10 pathway.EGCG inhibited HG-mediated NLRP3 inflammasome activation at least partly by stimulating sRAGE,thereby reducing IL-1βrelease.

Hydrogen sulfide reduces oxidative stress in Huntington's disease via Nrf2

The pathophysiology of Huntington's disease involves high levels of the neurotoxin quinolinic acid. Quinolinic acid accumulation results in oxidative stress, which leads to neurotoxicity. However, the molecular and cellular mechanisms by which quinolinic acid contributes to Huntington's disease pathology remain unknown. In this study, we established in vitro and in vivo models of Huntington's disease by administering quinolinic acid to the PC12 neuronal cell line and the striatum of mice, respectively. We observed a decrease in the levels of hydrogen sulfide in both PC12 cells and mouse serum, which was accompanied by down-regulation of cystathionine β-synthase, an enzyme responsible for hydrogen sulfide production. However, treatment with NaHS(a hydrogen sulfide donor) increased hydrogen sulfide levels in the neurons and in mouse serum, as well as cystathionine β-synthase expression in the neurons and the mouse striatum, while also improving oxidative imbalance and mitochondrial dysfunction in PC12 cells and the mouse striatum. These beneficial effects correlated with upregulation of nuclear factor erythroid 2-related factor 2 expression. Finally, treatment with the nuclear factor erythroid 2-related factor 2inhibitor ML385 reversed the beneficial impact of exogenous hydrogen sulfide on quinolinic acid-induced oxidative stress. Taken together, our findings show that hydrogen sulfide reduces oxidative stress in Huntington's disease by activating nuclear factor erythroid 2-related factor 2,suggesting that hydrogen sulfide is a novel neuroprotective drug candidate for treating patients with Huntington's disease.

Lactobacillus plantarum J26 alleviates alcohol-induced oxidative liver injury by regulating the Nrf2 signaling pathway

Oxidative stress is one of the main ways to cause alcohol-induced liver injury,and alcoholic liver disease(ALD)has been a common health problem worldwide.Lactic acid bacteria(LAB)is also considered as a potential treatment to alleviate alcohol-induced liver injury.Lactobacillus plantarum J26 is a LAB isolated from Chinese traditional fermented dairy products with excellent probiotic effects.This study aimed to establish a mice model of alcoholic liver injury through acute-on-chronic alcohol feeding and to study the alleviating effect of pre-intake of L.plantarum J26 on alcohol-induced oxidative liver injury and focus on its potential mechanism of alleviating effect.The results showed that pre-intake of L.plantarum J26 could improve liver pathological changes,reduce lipid accumulation,increase mitochondrial ATP and mitochondrial(mtDNA)levels,and alleviate liver injury.In addition,pre-intake L.plantarum J26 can improve the level of short-chain fatty acids(SCFAs)in the intestines in mice,short chain fatty acids can be used as a signaling molecule activation of nuclear factor E2-related factor 2(Nrf2)signaling pathway to alleviate liver oxidative stress,and maintain mitochondrial homeostasis by regulating the expression of genes related to mitochondrial dynamics and autophagy,thereby reducing cell apoptosis to alleviate alcohol-induced oxidative liver injury.

Procyanidin A_1 and its digestive products alleviate acrylamide-induced IPEC-J2 cell damage through regulating Keap1/Nrf2 pathway

Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In this study,we elucidated the molecular mechanism for and D-A_(1) to alleviate ACR-stimulated IPEC-J2 cell damage.ACR slightly activated nuclear factor erythroid 2-related factor 2(Nrf2)signaling and its target genes,but this activation could not reduce intestine cell damage.A_(1) and D-A_(1) could alleviate ACR-induced cell damage,but the effect was abrogated in cells transiently transfected with Nrf2 small interfering RNA(siRNA).Further investigation confirmed that A_(1) and D-A_(1) interacted with Ketch-like ECH-associated protein 1(Keapl),which boosted the stabilization of Nrf2,subsequently promoted the translocation of Nrf2 into the nucleus,and further increased the expression of antioxidant proteins,thereby inhibiting glutathione(GSH)consumption,maintaining redox balance and eventually alleviating ACR-induced cell damage.Importantly,there was no difference between A_(1) and D-A_(1) treated groups,indicating that A_(1) can tolerate gastrointestinal digestion and may be a potential compound to limit the toxicity of ACR.

Functionalized selenium nanoparticles ameliorated acetaminophen-induced hepatotoxicity through synergistically triggering PKCδ/Nrf2 signaling pathway and inhibiting CYP 2E1

Selenium nanoparticles(SeNPs)have been demonstrated potential for use in diseases associated with oxidative stress.Functionalized SeNPs with lower toxicity and higher biocompatibility could bring better therapeutic activity and clinical application value.Herein,this work was conducted to investigate the protective effect of Pleurotus tuber-regium polysaccharide-protein complex funtionnalized SeNPs(PTR-SeNPs)against acetaminophen(APAP)-induced oxidative injure in HepG2 cells and C57BL/6J mouse liver.Further elucidation of the underlying molecular mechanism,in particular their modulation of Nrf2 signaling pathway was also performed.The results showed that PTR-SeNPs could significantly ameliorate APAP-induced oxidative injury as evidenced by a range of biochemical analysis,histopathological examination and immunoblotting study.PTR-SeNPs could hosphorylate and activate PKCδ,depress Keap1,and increase nuclear accumulation of Nrf2,resulting in upregulation of GCLC,GCLM,HO-1 and NQO-1 expression.Besides,PTR-SeNPs suppressed the biotransformation of APAP to generate intracellular ROS through CYP 2E1 inhibition,restoring the mitochondrial morphology.Furthermore,the protective effect of PTR-SeNPs against APAP induced hepatotoxicity was weakened as Nrf2 was depleted in vivo,indicating the pivotal role of Nrf2 signaling pathway in PTR-SeNPs mediated hepatoprotective efficacy.Being a potential hepatic protectant,PTR-SeNPs could serve as a new source of selenium supplement for health-promoting and biomedical applications.

Effect of NF-κB p65 antisense oligodeoxynucleotide on transdifferentiation of normal human lens epithelial cells induced by transforming growth factor-β2

AIM：To study the inhibition of nuclear factor kappa-B p65（NF-κB p65）antisense oligodeoxynucleotide（ASODN）on transdifferentiation of normal human lens epithelial cells induced by transforming growth factor-β2（TGF-β2）.·M ETHODS：NF-κBp65ASODNand NF-κBp65missense oligodeoxynucleotide（MSODN）were designed and synthesized.Human lens epithelial cell line（HLE B-3）cells were prepared for study and divided into 7 groups.Control group was HLE B-3 cells cultured in dulbecco’s modified eagle medium（DMEM）.T1,T2,and T3 group were HLE B-3 cells cultured in DMEM with 10 ng/m L TGF-β2 for 6h,12h,24h respectively.A＋T group was HLE B-3 cells cultured with 10 ng/m L TGF-β2for 24h after transfected by NF-κB p65 ASODN for 24h.M＋T group was HLE B-3 cells cultured with 10 ng/m L TGF-β2 for 24h after transfected by NF-κB p65 MSODN for 24h.The negative control group was HLE B-3 cells cultured with 10 ng/m L TGF-β2 for 24h after cultured with transfer agent（Hi Per Fect）for 24h.Cell morphology was observed at different time points using an inverted microscope.The expression of NF-κB p65 m RNA was detected with reverse transcription-polymerase chain reaction（RT-PCR）,and the expression ofα-smooth muscle actin（α-SMA）protein was assayed with ELISA.·RESULTS：With the TGF-β2 stimulation prolongation,the expression of NF-κB p65 m RNA and a-SMA protein increased in T1,T2,T3 groups compared with the control group,and the difference was statistically significant（〈0.05）.NF-κB p65 ASODN lowered the expression of NF-κB p65 m RNA andα-SMA protein induced by TGF-β2.NF-κB p65 MSODN and Hi Per Fect did not lower the expression of NF-κB p65 m RNA andα-SMA protein induced by TGF-β2.The difference between control group and A＋T group was not statistically significant（〉0.05）,but the difference among A＋T group and other groups was statistically significant（〈0.05）.·CONCLUSION：NF-κB p65 ASODN could lower the expression of NF-κB p65 m RNA andα-SMA protein induced by TGF-β2,and antagonized TGF-β2-induced transdifferentiation of HLE B-3.NF-κB p65ASODN could be used as a new biological therapeutic target of posterior capsular opacification.

温阳益髓方对膝骨关节炎模型大鼠膝关节软骨、骨代谢及NOX2/ROS/NF-κB水平的影响

目的:探讨温阳益髓方对膝骨关节炎模型大鼠膝关节软骨、骨代谢及NOX2/ROS/NF-κB水平的影响。方法:选取40只SPF级SD雄性大鼠,随机分为正常组、模型组、低剂量温阳益髓方(低剂量)组、高剂量温阳益髓方(高剂量)组。除正常组外,其余3组均采用膝关节腔注射0.05 mL(20 mg/mL)碘乙酸钠,建立膝骨关节炎模型。建模成功后,低、高剂量组分别以6、24 mg/kg温阳益髓方汤剂灌胃,正常组、模型组以同体积生理盐水灌胃。采用H-E染色、光镜观察各组膝关节软骨组织的形态结构;ELISA法检测血清骨代谢相关指标水平;二氢乙锭荧光探针检测膝关节软骨组织活性氧(ROS)水平;免疫印迹检测膝关节软骨组织NADPH氧化酶2(NOX2)、核因子-κB(NF-κB)水平。结果:模型组膝关节软骨组织边缘的软骨基质减少、软骨囊结构不清、软骨细胞减少,且出现钙化灶。与模型组比较,低、高剂量组上述结构变化明显改善。与正常组比较,模型组Mankin评分显著升高;与模型组比较,低、高剂量组Mankin评分显著降低,且高剂量组低于低剂量组。与正常组比较,模型组血清骨钙素(OCN)、Ⅰ型胶原C末端肽(CTX-Ⅰ)水平显著降低,软骨寡聚基质蛋白(COMP)水平显著升高;与模型组比较,低、高剂量组血清OCN、CTX-Ⅰ水平显著升高,且高剂量组高于低剂量组,COMP水平显著降低,且高剂量组低于低剂量组。与正常组比较,模型组ROS水平显著升高;与模型组比较,低、高剂量组ROS水平显著降低,且高剂量组低于低剂量组。与正常组比较,模型组NOX2、NF-κB水平显著升高;与模型组比较,低、高剂量组NOX2、NF-κB水平显著降低,且高剂量组低于低剂量组。结论:温阳益髓方可改善膝骨关节炎模型大鼠膝关节软骨、骨代谢,其机制可能与其降低膝关节软骨组织NOX2/ROS/NF-κB水平有关。

Oxidative stress in retinal pigment epithelium degeneration:from pathogenesis to therapeutic targets in dry age-related macular degeneration

Age-related macular degeneration is a primary cause of blindness in the older adult population. Past decades of research in the pathophysiology of the disease have resulted in breakthroughs in the form of anti-vascular endothelial growth factor therapies against neovascular age-related macular degeneration;however, effective treatment is not yet available for geographical atrophy in dry agerelated macular degeneration or for preventing the progression from early or mid to the late stage of age-related macular degeneration. Both clinical and experimental investigations involving human agerelated macular degeneration retinas and animal models point towards the atrophic alterations in retinal pigment epithelium as a key feature in age-related macular degeneration progression. Retinal pigment epithelium cells are primarily responsible for cellular-structural maintenance and nutrition supply to keep photoreceptors healthy and functional. The retinal pigment epithelium constantly endures a highly oxidative environment that is balanced with a cascade of antioxidant enzyme systems regulated by nuclear factor erythroid-2-related factor 2 as a main redox sensing transcription factor. Aging and accumulated oxidative stress triggers retinal pigment epithelium dysfunction and eventually death. Exposure to both environmental and genetic factors aggravates oxidative stress damage in aging retinal pigment epithelium and accelerates retinal pigment epithelium degeneration in age-related macular degeneration pathophysiology. The present review summarizes the role of oxidative stress in retinal pigment epithelium degeneration, with potential impacts from both genetic and environmental factors in age-related macular degeneration development and progression. Potential strategies to counter retinal pigment epithelium damage and protect the retinal pigment epithelium through enhancing its antioxidant capacity are also discussed, focusing on existing antioxidant nutritional supplementation, and exploring nuclear factor erythroid-2-related factor 2 and its regulators including REV-ERBα as therapeutic targets to protect against age-related macular degeneration development and progression.

BaP通过AhR和Nrf2信号通路对HepG2细胞中GSTP1的影响

目的探究苯并芘(benzo[a]pyrene,BaP)通过芳香烃受体(aryl hydrocarbon receptor,AhR)和核因子E2相关因子(subcellular localization of nuclear factor E2-related factor 2,Nrf2)信号通路对HepG2细胞中谷胱甘肽-S-转移酶P1(glutathione s-transferase P1,GSTP1)的影响。方法将体外培养HepG2细胞分为Control组、BaP(10μmol/L)组、BaP(10μmol/L)+AhR抑制剂(1μmol/L)组和BaP(10μmol/L)+Nrf2抑制剂(1μmol/L)组。BaP组给予10μmol/L BaP培养24 h,抑制剂组给予1μmol/L抑制剂0.5 h后,加入10μmol/L BaP培养24 h,采用Western Blot和qPCR实验方法检测各组AhR、Nrf2、细胞色素P450s(cytochrome P450s,CYPs)、血红素加氧酶-1(heme oxygenase-1,HO-1)及GSTP1基因和蛋白的表达。结果与Control组相比,BaP组中AhR、Nrf2、GSTP1、CYP1A1及HO-1的mRNA和蛋白表达均升高(P<0.05);与BaP组相比,BaP+AhR抑制剂组中AhR、GSTP1和CYP1A1的mRNA和蛋白表达均降低(P<0.05),BaP+Nrf2抑制剂组中Nrf2、GSTP1和HO-1的表达均降低(P<0.05);与BaP+AhR抑制剂组相比,BaP+Nrf2抑制剂组GSTP1 mRNA和蛋白的表达降低,差异有统计学意义(P<0.05)。结论BaP通过AhR和Nrf2两条信号通路增加GSTP1的表达,以Nrf2信号通路为主导影响GSTP1的表达。

Mangiferin Promotes Bregs Level,Activates Nrf2 Antioxidant Signaling,and Inhibits Proinflammatory Cytokine Expression in Murine Splenic Mononuclear Cells In Vitro

Recent studies indicated that regulatory B cells(Bregs)and nuclear factor erythroid 2-related factor 2(Nrf2)antioxidant signaling pathway play important roles in the pathogenesis of chronic graft-versus-host disease(cGVHD).Mangiferin(MA),a polyphenol compound,has been reported to activate Nrf2/antioxidant-responsive element(ARE)signaling pathway.This study was aimed to investigate the effects of MA on Bregs and Nrf2 antioxidant signaling in murine splenic mononuclear cells(MNCs)in vitro.Our results revealed that MA could increase the Bregs level in murine splenic MNCs.Moreover,MA up-regulated the expression of Bregs-associated immunosuppressive factor interleukin-10(IL-10)by activating the Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3)and extracellular signal-regulated kinase(ERK)signaling in murine splenic MNCs.Meanwhile,MA inhibited the proinflammatory cytokines IL-2 and interferon-y(INF-y)at both mRNA and protein levels.MA also enhanced the transcription and protein expression of Nrf2 and NADPH quinine oxidoreductase 1(NQOl),whereas decreased that of Kelch-like ECH-associated protein 1(Keapl)in murine splenic MNCs.Moreover,MA promoted the proliferation and inhibited the apoptosis of murine splenic MNCs.These results suggested that MA exerts immunosuppressive effects by upregulating the Bregs level,activating the Nrf2 antioxidant pathway,and inhibiting the expression of pro-immunoinflammatory factors.MA,as a natural immunomodulatory and anti-inflammatory agent,may have a potential role in the prophylaxis and treatment of cGVHD.

脑泰方对脑缺血/再灌注大鼠海马区Nrf2、HO-1和膜铁转运辅助蛋白表达的影响

目的研究益气活血中药脑泰方通过Keap1-Nrf2/ARE信号通路对脑缺血/再灌注后大鼠海马区血红素加氧酶-1(heme oxygenase-1,HO-1)和膜铁转运辅助蛋白(hephaestin,Heph)表达的影响。方法将80只♂大鼠随机分为假手术组、模型组、脑泰方低剂量组(4.5 g·kg^(-1))、中剂量组(9 g·kg^(-1))和高剂量组(18 g·kg^(-1))。各组大鼠术前连续灌胃给药3 d,每日1次,再行大脑中动脉线栓法脑缺血/再灌注模型制备术,术后连续灌胃给药2 d。术后72 h采用Zea Longa神经功能学评分标准记录大鼠行为活动,TTC染色法测定脑梗死体积,real-time PCR检测大鼠海马区Nrf2、HO-1、Heph的mRNA表达,Western blot检测Nrf2、HO-1、Heph的蛋白表达。结果与模型组比较,脑泰方中、高剂量组的神经行为学评分明显下降(P<0.01),各脑泰方组脑梗死体积明显缩小(P<0.01);HO-1 mRNA表达均增加(P<0.05)。脑泰方中、高剂量组Heph mRNA表达增加(P<0.05);Nrf2和Heph蛋白表达明显增加(P<0.05,P<0.01)。各脑泰方组HO-1蛋白表达增高(P<0.01)。结论脑泰方能减轻脑缺血/再灌注损伤,其机制可能是通过激活Keap1-Nrf2/ARE信号通路,促进HO-1生成,上调Heph的表达,减少脑铁沉积,发挥脑缺血/再灌注后神经元的保护作用。

叶黄素对H2O2诱导的人视网膜Muller细胞氧化应激干预的作用机制

背景氧化应激是年龄相关性黄斑变性（AMD）的主要因素之一。研究表明叶黄素对AMD有预防作用，但是其抗氧化机制仍不明确。Mμller细胞是视网膜氧化应激反应的靶细胞之一，研究叶黄素对MUller细胞的氧化应激是否具有保护作用及其作用机制对于视网膜疾病的治疗具有重要意义。目的研究叶黄素对视网膜Mμller细胞核因子E2相关转录因子2／抗氧化反应原件（Nrf2／ARE）信号途径的影响。方法人Muller细胞株进行常规培养，将对数生长期的细胞接种于96孔培养板，在培养液中分别加入不同浓度（40、80、160、320、640ixmol／L）HO2，绘制Mμller细胞的凋亡曲线，取H2O2的半数致死量，即160μmol／L制备Mμller细胞氧化应激模型。将模型细胞分为模型对照组和不同质量浓度（12．5、25．0、50．0mg／L）叶黄素组，根据分组情况分别在培养液中加入相应质量浓度的叶黄素，用常规培养的细胞作为空白对照组。采用MTT比色法测定各组中Maller细胞增生值（吸光度，A值）和凋亡率；采用流式细胞仪检测各组细胞中活性氧簇（ROS）的荧光强度；采用实时荧光定量PCR检测细胞中Nrf2mRNA和血红素加氧酶-1（HO-1）mRNA的相对表达量；采用Westernblot法检测各组细胞中Nrf2和HO-1蛋白的表达水平（灰度值）。结果MTT比色法检测显示，随着H2O2浓度的增加，细胞增生抑制率逐渐增加，各组间总体比较差异有统计学意义（F=43．890，P〈0．01）。空白对照组、模型对照组及12．5、25．0、50．0mg／L叶黄素组细胞凋亡率的总体比较差异有统计学意义（F=346．770，P=0．000），其中随着叶黄素质量浓度的增加，细胞凋亡率逐渐下降，组间比较差异均有统计学意义（均P〈0．05）。空白对照组、模型对照组及12．5、25．0、50．0mg／L叶黄素组细胞中ROS含量分别为1．92±0．18、64．89±2．86、52．70±2．80、32．61±4．20和5．68±1．35，随着叶黄素质量浓度的增加，ROS含量逐渐下降，组间总体比较差异有统计学意义（F=324．900，P=0．000）。各质量浓度叶黄素组细胞中Nrf2和HO一1mRNA相对表达量及细胞中HO-1和细胞核中Nrf2蛋白表达量均明显高于模型对照组，各组间总体比较差异均有统计学意义（F=236．960、242．620、186．830、263．120，均P=0．000），随着叶黄素质量浓度的增加，Nrf2mRNA和HO-1mRNA及其蛋白的表达量逐渐增加，组间比较差异均有统计学意义（均P〈0．05），但各组间Muller细胞的细胞质中Nrf2蛋白表达量总体比较差异无统计学意义（F=1．790，P=0．210）。结论叶黄素通过上调Nrf2的表达和核转位诱导抗氧化酶的表达，从而抑制Mailer细胞的氧化应激反应。

基于Keap-1/Nrf2信号通路探究异甘草酸镁改善非酒精性脂肪性肝病大鼠糖脂代谢紊乱的作用机制

目的观察异甘草酸镁对非酒精性脂肪性肝病(NAFLD)大鼠糖脂代谢的影响,并探讨相关机制。方法30只NAFLD大鼠随机数字法分为NAFLD组、异甘草酸镁组、联合组,每组10只;另取10只健康大鼠,设为正常对照组。联合组大鼠腹腔注射异甘草酸镁(100 mg/kg),腹腔注射核因子E2相关因子2(Nrf2)抑制剂ML385(30 mg/kg,溶于5 mL DMSO);异甘草酸镁组大鼠腹腔注射异甘草酸镁(100 mg/kg),腹腔注射等容量DMSO;正常对照组、NAFLD组大鼠腹腔注射等容量生理盐水,腹腔注射等体积DMSO。每日1次,干预4周。检测大鼠血糖、血脂及肝功能指标;检测血清氧化应激指标;免疫印迹法检测肝组织Nrf2、Keap1蛋白表达量。结果与正常对照组比较,NAFLD组血清空腹血糖(FPG)、空腹胰岛素(FINS)、三酰甘油(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、谷草转氨酶(AST)、丙氨酸氨基转移酶(ALT)、丙二醛(MDA)水平及肝组织Nrf2蛋白表达量均升高,血清超氧化物歧化酶(SOD)活性、肝组织Kelch样环氧氯丙烷相关蛋白1(Keap1)蛋白表达量降低(P<0.05)。与NAFLD组比较,异甘草酸镁组血清FPG、FINS、TG、TC、LDL-C、AST、ALT、MDA水平及肝组织Nrf2蛋白表达量均降低,血清SOD活性、肝组织Keap1蛋白表达量升高(P<0.05);与异甘草酸镁组比较,联合组血清FPG、FINS、HOMA-IR、TG、TC、LDL-C、AST、ALT、MDA水平及肝组织Nrf2蛋白表达量均升高,血清SOD活性、肝组织Keap1蛋白表达量降低(P<0.05)。结论异甘草酸镁可改善NAFLD大鼠糖脂代谢紊乱,抑制氧化应激并改善肝功能,其作用机制可能与激活Keap-1/Nrf2信号通路有关。

Nrf2在脑铁代谢中作用的研究进展

神经细胞的铁代谢平衡对大脑的正常功能至关重要。很多脑部疾病常常伴随有脑铁代谢(brain iron metabolism)的紊乱。这种紊乱不加控制可以引起神经细胞的铁死亡(ferroptosis)--一种可调控性细胞死亡(regulated cell death,RCD)形式,其特征是铁过载引起的脂质过氧化(lipid peroxidation,LPO)积累。作为一种转录因子,核因子E2相关因子2(nuclear factor E2-related factor 2,Nrf2)调控许多与脑铁代谢和铁死亡相关的基因。

核转录因子相关因子2的活化在肿瘤代谢中的作用

核转录因子(NF-E2)相关因子2(nuclear factor erythroid 2 related factor 2,Nrf2)是细胞应对外界应激的主要调控因子,通过调控多种靶基因的表达,在生理条件下减轻氧化应激,维持细胞稳态。其上游受多种因素调控,包括氧化与亲电应激、外界营养状态、细胞内代谢中间产物和能量状态等。在肿瘤细胞中,异常活跃的Nrf2使其抗氧化能力增强,并且通过介导代谢重编程(metabolic reprogramming),促进肿瘤细胞增殖和生长。Keap1(Kelch-like ECH-associated protein 1)是氧化和亲电应激感受器,通过募集泛素降解系统,对Nrf2的活性起主要调控作用。本文介绍Keap1依赖与非依赖条件下Nrf2的活化途径,着重介绍在肿瘤中Nrf2的异常活化,以及如何调控代谢重编程进而调节肿瘤细胞的合成代谢,最终促进肿瘤的进展。