Neferine inhibits the progression of diabetic nephropathy by modulating the miR-17-5p/nuclear factor E2-related factor 2 axis

OBJECTIVE:To investigate the effect of Neferine(Nef)on diabetic nephropathy(DN)and to explore the mechanism of Nef in DN based on miRNA regulation theory.METHODS:A DN mouse model was constructed and treated with Nef.Serum creatinine(Crea),blood urea(UREA)and urinary albumin were measured in mice by kits,and renal histopathological changes and fibrosis were observed by hematoxylin-eosin staining and Masson staining.Renal tissue superoxide dismutase(SOD),malondialdehyde(MDA)and glutathione peroxidase(GSH-Px)activities were measured by enzyme-linked immunosorbent assay(ELISA).Western blotting was used to detect the expression of nuclear factor E2-related factor 2(Nrf2)/heme oxygenase 1(HO-1)signaling pathway-related proteins in kidney tissues.Quantitative reverse transcription-polymerase chain reaction(q RT-PCR)was used to detect the expression of miR-17-5p in kidney tissues.Subsequently,a DN in vitro model was constructed by high glucose culture of human mesangial cells(HMCs),cells were transfected with miR-17-5p mimic and/or treated with Nef,and we used q RTPCR to detect cellular miR-17 expression,flow cytometry to detect apoptosis,ELISAs to detect cellular SOD,MDA,and GSH-Px activities,Western blots to detect Nrf2/HO-1 signaling pathway-related protein expression,and dual luciferase reporter gene assays to verify the targeting relationship between Nrf2 and miR-17-5p.RESULTS:Administration of Nef significantly reduced the levels of blood glucose,Crea,and UREA and the expression of miR-17-5p,improved renal histopathology and fibrosis,significantly reduced MDA levels,elevated SOD and GSH-Px activities,and activated Nrf2 expression in kidney tissues from mice with DN.Nrf2 is a post-transcriptional target of miR-17-5p.In HMCs transfected with miR-17-5p mimics,the m RNA and protein levels of Nrf2 were significantly suppressed.Furthermore,miR-17-5p overexpression and Nef intervention resulted in a significant increase in high glucose-induced apoptosis and MDA levels in HMCs and a significant decrease in the protein expression of HO-1 and Nrf2.CONCLUSION:Collectively,these results indicate that Nef has an ameliorative effect on DN,and the mechanism may be through the miR-17-5p/Nrf2 pathway.

Targeting nuclear factor erythroid 2-related factor 2-regulated ferroptosis to treat nervous system diseases

By critically examining the work,we conducted a comprehensive bibliometric analysis on the role of nuclear factor erythroid 2-related factor 2(NRF2)in nervous system diseases.We also proposed suggestions for future bibliometric studies,including the integration of multiple websites,analytical tools,and analytical approaches,The findings presented provide compelling evidence that ferroptosis is closely associated with the therapeutic challenges of nervous system diseases.Targeted modulation of NRF2 to regulate ferroptosis holds substantial potential for effectively treating these diseases.Future NRF2-related research should not only focus on discovering new drugs but also on designing rational drug delivery systems.In particular,nanocarriers offer substantial potential for facilitating the clinical translation of NRF2 research and addressing existing issues related to NRF2-related drugs.

Colony-stimulating factor 3 and its receptor promote leukocyte immunoglobulin-like receptor B2 expression and ligands in gastric

BACKGROUND Colony-stimulating factor 3(CSF3)and its receptor(CSF3R)are known to promote gastric cancer(GC)growth and metastasis.However,their effects on the immune microenvironment remain unclear.Our analysis indicated a potential link between CSF3R expression and the immunosuppressive receptor leukocyte immunoglobulin-like receptor B2(LILRB2)in GC.We hypothesized that CSF3/CSF3R may regulate LILRB2 and its ligands,angiopoietin-like protein 2(ANGPTL2)and human leukocyte antigen-G(HLA-G),contributing to immunosuppression.AIM To investigate the relationship between CSF3/CSF3R and LILRB2,as well as its ligands ANGPTL2 and HLA-G,in GC.METHODS Transcriptome sequencing data from The Cancer Genome Atlas were analyzed,stratifying patients by CSF3R expression.Differentially expressed genes and immune checkpoints were evaluated.Immunohistochemistry(IHC)was performed on GC tissues.Correlation analyses of CSF3R,LILRB2,ANGPTL2,and HLA-G were conducted using The Cancer Genome Atlas data and IHC results.GC cells were treated with CSF3,and expression levels of LILRB2,ANGPTL2,and HLA-G were measured by quantitative reverse transcriptase-polymerase chain reaction and western blotting.RESULTS Among 122 upregulated genes in high CSF3R expression groups,LILRB2 showed the most significant increase.IHC results indicated high expression of LILRB2(63.0%),ANGPTL2(56.5%),and HLA-G(73.9%)in GC tissues.Strong positive correlations existed between CSF3R and LILRB2,ANGPTL2,and HLA-G mRNA levels(P<0.001).IHC confirmed positive correlations between CSF3R and LILRB2(P<0.001),and HLA-G(P=0.010),but not ANGPTL2(P>0.05).CSF3 increased LILRB2,ANGPTL2,and HLA-G expression in GC cells.Heterogeneous nuclear ribonucleoprotein H1 modulation significantly altered their expression,impacting CSF3’s regulatory effects.CONCLUSION The CSF3/CSF3R pathway may contribute to immunosuppression in GC by upregulating LILRB2 and its ligands,with heterogeneous nuclear ribonucleoprotein H1 playing a regulatory role.

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.

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.

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.

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.

Evaluation of combined detection of nuclear factor erythroid 2-related factor 2 and glutathione peroxidase 4 in primary hepatic carcinoma and preliminary exploration of pathogenesis

This study aims to analyze the clinical significance and mechanism of nuclear factor erythroid 2-related factor 2(NRF2)and glutathione peroxidase 4(GPX4)in primary hepatic carcinoma(PHC).Methods:The expression of NRF2 and GPX4 in peripheral blood of patients with PHC was determined to analyze the diagnostic value of the two combined for PHC.The prognostic significance of NRF2 and GPX4 was evaluated by 3-year followup.Human liver epithelial cells THLE-2 and human hepatocellular carcinoma cells HepG2 were purchased,and the expression of NRF2 and GPX4 in the cells was determined.NRF2 and GPX4 aberrant expression vectors were constructed and transfected into HepG2,and changes in cell proliferation and invasion capabilities were observed.Results:The expression of NRF2 and GPX4 in patients with PHC was higher than that in patients with LC or VH(p<0.05),and the two indicators combined was excellent in diagnosing PHC.Moreover,patients with high expression of NRF2 and GPX4 had a higher risk of death(p<0.05).In in vitro experiments,both NRF2 and GPX4 expression was elevated in HepG2(p<0.05).HepG2 activity was enhanced by increasing the expression of the two,vice versa(p<0.05).Conclusion:NRF2 and GPX4 combined is excellent in diagnosing PHC,and promotes the malignant development of PHC.

Aberrant activation of nuclear factor of activated T cell 2 in lamina propria mononuclear cells in ulcerative colitis

AIM:To investigate the role of nuclear factor of activated T cell 2(NFAT2),the major NFAT protein in peripheral T cells,in sustained T cell activation and intractable inflammation in human ulcerative colitis(UC). METHODS:We used two-dimensional gel-electrophoresis, immunohistochemistry,double immunohistochemical staining,and confocal microscopy to inspect the expression of NFAT2 in 107,15,48 and 5 cases of UC, Crohn's disease(CD),non-specific colitis,and 5 healthy individuals,respectively. RESULTS:Up-regulation with profound nucleo- translocation/activation of NFAT2 of lamina propria mononuclear cells(LPMC)of colonic mucosa was found specifically in the affected colonic mucosa from patients with UC,as compared to CD or NC(P<0.001,Kruskal- Wallis test).Nucleo-translocation/activation of NFAT2 primarily occurred in CD8+T,but was less prominent in CD4+T cells or CD20+B cells.It was strongly associated with the disease activity,including endoscopic stage (τ=0.2145,P=0.0281)and histologic grade(τ=0.4167, P<0.001). CONCLUSION:We disclose for the first time the nucleo-translocation/activatin of NFAT2 in lamina propria mononuclear cells in ulcerative colitis.Activation of NFAT2 was specific for ulcerative colitis and highly associated with disease activity.Since activation of NFAT2is implicated in an auto-regulatory positive feedback loop of sustained T-cell activation and NFAT proteins play key roles in the calcium/calcineurin signaling pathways,our results not only provide new insights into the mechanism for sustained intractable inflammation,but also suggest the calcium-calcineurin/NFAT pathway as a new therapeutic target for ulcerative colitis.

Short hairpin RNA-mediated knockdown of nuclear factor erythroid 2-like 3 exhibits tumor-suppressing effects in hepatocellular carcinoma cells

BACKGROUND Hepatocellular carcinoma(HCC) is one of the most common malignant tumors with high mortality-to-incidence ratios. Nuclear factor erythroid 2-like 3(NFE2 L3), also known as NRF3, is a member of the cap ‘n' collar basic-region leucine zipper family of transcription factors. NFE2 L3 is involved in the regulation of various biological processes, whereas its role in HCC has not been elucidated.AIM To explore the expression and biological function of NFE2 L3 in HCC.METHODS We analyzed the expression of NFE2 L3 in HCC tissues and its correlation with clinicopathological parameters based on The Cancer Genome Atlas(TCGA) data portal. Short hairpin RNA(shRNA) interference technology was utilized to knock down NFE2 L3 in vitro. Cell apoptosis, clone formation, proliferation, migration,and invasion assays were used to identify the biological effects of NFE2 L3 in BEL-7404 and SMMC-7721 cells. The expression of epithelial-mesenchymal transition(EMT) markers was examined by Western blot analysis.RESULTS TCGA analysis showed that NFE2 L3 expression was significantly positively correlated with tumor grade, T stage, and pathologic stage. The qPCR and Western blot results showed that both the mRNA and protein levels of NFE2 L3 were significantly decreased after shRNA-mediated knockdown in BEL-7404 and SMMC-7721 cells. The shRNA-mediated knockdown of NFE2 L3 could induce apoptosis and inhibit the clone formation and cell proliferation of SMMC-7721 and BEL-7404 cells. NFE2 L3 knockdown also significantly suppressed the migration, invasion, and EMT of the two cell lines.CONCLUSION Our study showed that shRNA-mediated knockdown of NFE2 L3 exhibited tumor-suppressing effects in HCC cells.

Role of nuclear factor (erythroid-derived 2)-like 2 in metabolic homeostasis and insulin action: A novel opportunity for diabetes treatment?

Redox balance is fundamentally important for physiological homeostasis. Pathological factors that disturb this dedicated balance may result in oxidative stress, leading to the development or aggravation of a variety of diseases, including diabetes mellitus, cardiovascular diseases, metabolic syndrome as well as inflammation, aging and cancer. Thus, the capacity of endogenous free radical clearance can be of patho-physiological importance; in this regard, the major reactive oxygen species defense machinery, the nuclear factor (erythroid-derived 2)-like 2 (Nrf2) system needs to be precisely modulated in response to pathological alterations. While oxidative stress is among the early events that lead to the development of insulin resistance, the activation of Nrf2 scavenging capacity leads to insulin sensitization. Furthermore, Nrf2 is evidently involved in regulating lipid metabolism. Here we summarize recent findings that link the Nrf2 system to metabolic homeostasis and insulin action and present our view that Nrf2 may serve as a novel drug target for diabetes and its complications.

Sinapic acid ameliorates D-galactosamine/lipopolysaccharideinduced fulminant hepatitis in rats:Role of nuclear factor erythroidrelated factor 2/heme oxygenase-1 pathways

BACKGROUND Sinapic acid(SA)has been shown to have various pharmacological properties such as antioxidant,antifibrotic,anti-inflammatory,and anticancer activities.Its mechanism of action is dependent upon its ability to curb free radical production and protect against oxidative stress-induced tissue injuries.AIM To study the hepatoprotective effects of SA against lipopolysaccharide(LPS)/Dgalactosamine(D-GalN)-induced acute liver failure(ALF)in rats.METHODS Experimental ALF was induced with an intraperitoneal(i.p.)administration of 8μg LPS and 800 mg/kg D-GalN in normal saline.SA was administered orally once daily starting 7 d before LPS/D-GalN treatment.RESULTS Data showed that SA ameliorates acute liver dysfunction,decreases serum levels of alanine transaminase(ALT),and aspartate aminotransferase(AST),as well as malondialdehyde(MDA)and NO levels in ALF model rats.However,pretreatment with SA(20 mg/kg and 40 mg/kg)reduced nuclear factor kappalight-chain-enhancer of activated B cells(NF-κB)activation and levels of inflammatory cytokines(tumor necrosis factor-αand interleukin 6).Also,SA increased the activity of the nuclear factor erythroid-related factor 2/heme oxygenase-1(Nrf2/HO-1)signaling pathway.CONCLUSION In conclusion,SA offers significant protection against LPS/D-GalN-induced ALF in rats by upregulating Nrf2/HO-1 and downregulating NF-κB.

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.

核因子E2相关因子2介导铁死亡在新生儿缺氧缺血性脑病中的研究进展

新生儿缺氧缺血性脑病(HIE)是一种新生儿常见疾病,其致残率和致死率极高,且缺乏特异的治疗方法。HIE的重要机制是活性氧(ROS)大量生成与抗氧化能力缺失所致的氧化应激。铁死亡作为一种由铁依赖性脂质过氧化和ROS积累引起的程序性细胞死亡,在HIE的发生发展中发挥重要作用。核因子E2相关因子2(NRF2)是人体氧化应激反应的主要调控因子,大量研究表明NRF2调控多种与脑铁代谢和铁死亡相关的基因,提示NRF2可能抑制HIE中铁死亡。因此,文章通过铁死亡、HIE和NRF2三者之间的联系就NRF2在HIE中的保护作用进行综述。

Context-dependent role of sirtuin 2 in inflammation

Sirtuin 2 is a member of the sirtuin family nicotinamide adenine dinucleotide(NAD~+)-dependent deacetylases, known for its regulatory role in different processes, including inflammation. In this context, sirtuin 2 has been involved in the modulation of key inflammatory signaling pathways and transcription factors by deacetylating specific targets, such as nuclear factor κB and nucleotide-binding oligomerization domain-leucine-rich-repeat and pyrin domain-containing protein 3(NLRP3). However, whether sirtuin 2-mediated pathways induce a pro-or an anti-inflammatory response remains controversial. Sirtuin 2 has been implicated in promoting inflammation in conditions such as asthma and neurodegenerative diseases, suggesting that its inhibition in these conditions could be a potential therapeutic strategy. Conversely, arthritis and type 2 diabetes mellitus studies suggest that sirtuin 2 is essential at the peripheral level and, thus, its inhibition in these pathologies would not be recommended. Overall, the precise role of sirtuin 2 in inflammation appears to be context-dependent, and further investigation is needed to determine the specific molecular mechanisms and downstream targets through which sirtuin 2 influences inflammatory processes in various tissues and pathological conditions. The present review explores the involvement of sirtuin 2 in the inflammation associated with different pathologies to elucidate whether its pharmacological modulation could serve as an effective strategy for treating this prevalent symptom across various diseases.

基于Keap1-Nrf2/HO-1信号通路探讨薏苡附子败酱散对UC模型大鼠结肠黏膜损伤的影响

目的:探析薏苡附子败酱散对于Kelch样环氧氯丙烷相关蛋白1-核因子E2相关因子2/血红素氧合酶1(Keap1-Nrf2/HO-1)信号通路的影响,阐释其对溃疡性结肠炎(UC)大鼠结肠黏膜损伤的作用机制。方法:选用80只SD大鼠雌雄各半,随机分为正常组、模型组、美沙拉嗪组(0.35 g·kg^(-1))、薏苡附子败酱散组(6.00 g·kg^(-1)),采用2,4,6-三硝基苯磺酸(TNBS)/乙醇联合灌肠法进行实验性UC造模。给药14 d期间,观察大鼠一般情况变化及疾病活动指数(DAI);苏木精-伊红染色(HE)法观察结肠病理学改变及结肠黏膜损伤指数(CMDI)评分;酶联免疫吸附试验(ELISA)法检测血清中白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)的含量;原位末端转移酶标记技术(TUNEL)染色法检测结肠组织细胞凋亡情况;生化法检测结肠组织中超氧化物歧化酶(SOD)及丙二醛(MDA)水平;实时荧光-聚合酶链式反应(qRT-PCR)检测结肠组织中Keap1、Nrf2及HO-1相对表达,蛋白质印迹(Westernblotting)法测定结肠组织中Keap1、Nrf2、HO-1蛋白表达。结果:与正常组比较,模型组大鼠体质量先降后升,DAI评分及CMDI评分上升(P<0.05),血清炎症因子(IL-6、TNF-α)含量均显著增加(P<0.05);结肠组织中MDA含量增加(P<0.05),SOD含量减少(P<0.05),TUNEL荧光染色阳性表达明显,Keap1mRNA表达水平及蛋白表达均明显升高(P<0.01),Nrf2、HO-1mRNA表达水平及蛋白表达均明显下降(P<0.05)。与模型组比较,给药组大鼠体质量增加值上升(P<0.05),DAI评分及CMDI评分降低(P<0.05),血清炎症因子(IL-6、TNF-α)含量均显著减少(P<0.05);结肠组织中MDA含量减少(P<0.05),SOD含量增加(P<0.05),TUNEL荧光染色阳性表达减弱,Keap1mRNA表达水平及蛋白表达均明显下降(P<0.05),Nrf2、HO-1mRNA表达水平及蛋白表达均明显上升(P<0.05)。结论:薏苡附子败酱散对UC大鼠结肠黏膜损伤有抑制作用,其机制可能是通过调控Keap1-Nrf2/HO-1通路,影响脂质过氧化进程,抑制局部细胞凋亡及促炎因子的释放实现的。

Effects of blueberry on hepatic fibrosis and transcription factor Nrf2 in rats

AIM:To investigate the effects of blueberry on hepatic fibrosis and NF-E2-related factor 2(Nrf2) transcription factor in rats.METHODS:Forty-five male Sprague-Dawley rats were randomly divided into control group(A);CCl4-induced hepatic fibrosis group(B);blueberry prevention group(C);Dan-shao-hua-xian capsule(DSHX) prevention group(D);and blueberry + DSHX prevention group(E).Liver fibrosis was induced in rats by subcutaneous injection of CCl4 and a high-lipid/low-protein diet for 8 wk(except the control group).The level of hyaluronic acid(HA) and alanine aminotransferase(ALT) in serum was examined.The activity of superoxide dismutase(SOD),glutathione-S-transferase(GST) and malondialdehyde(MDA) in liver homogenates was determined.The degree of hepatic fibrosis was evaluated by hematoxylin and eosin and Masson staining.Expression of Nrf2 and NADPH quinone oxidoreductase 1(Nqo1) was detected by real-time reversed transcribed-polymerase chain reaction,immunohistochemical techniques,and western blotting.RESULTS:Compared with group B,liver indices,levels of serum HA and ALT of groups C,D and E were reduced(liver indices:0.038 ± 0.008,0.036 ± 0.007,0.036 ± 0.005 vs 0.054 ± 0.009,P<0.05;HA:502.33 ± 110.57 ng/mL,524.25 ± 255.42 ng/mL,499.25 ± 198.10 ng/mL vs 828.50 ± 237.83 ng/mL,P<0.05;ALT:149.44 ± 16.51 U/L,136.88 ± 10.07 U/L,127.38 ± 11.03 U/L vs 203.25 ± 31.62 U/L,P<0.05),and SOD level was significantly higher,but MDA level was lower,in liver homogenates(SOD:1.36 ± 0.09 U/mg,1.42 ± 0.13 U/mg,1.50 ± 0.15 U/mg vs 1.08 ± 0.19 U/mg,P<0.05;MDA:0.294 ± 0.026 nmol/mg,0.285 ± 0.025 nmol/mg,0.284 ± 0.028 nmol/mg vs 0.335 ± 0.056 nmol/mg,P<0.05).Meanwhile,the stage of hepatic fibrosis was significantly weakened(P<0.05).Compared with group A,the activity of GST liver homogenates and expression levels of Nrf2 and Nqo1 in group B were elevated(P<0.05).The expression level of Nrf2 and Nqo1 in groups C,D,and E were increased as compared with group B,but the difference was not significant.CONCLUSION:Blueberry has preventive and protective effects on CCl4-induced hepatic fibrosis by reducing hepatocyte injury and lipid peroxidation.However,these effects may not be related to the activation of Nrf2 during long-term of CCl4.

High levels of homocysteine downregulate apolipoprotein E expression via nuclear factor kappa B

AIM: To investigate the effect of high homocysteine(Hcy) levels on apolipoprotein E(apoE) expression and the signaling pathways involved in this gene regulation.METHODS: Reverse transcriptase polymerase chain reaction(RT-PCR) and Western blot were used to assess apo E expression in cells treated with various concentrations(50-500 μmol/L) of Hcy. Calcium phosphatetransient transfections were performed in HEK-293 and RAW 264.7 cells to evaluate the effect of Hcy on apoE regulatory elements [promoter and distal multienhancer 2(ME2)]. To this aim, plasmids containing the proximal apoE promoter [(-500/+73)apoE construct] alone or in the presence of ME2 [ME2/(-500/+73)apoE construct] to drive the expression of the reporter luciferase gene were used. Co-transfection experiments were carried out to investigate the downstream effectors of Hcymediated regulation of apoE promoter by using specific inhibitors or a dominant negative form of IKβ. In other co-transfections, the luciferase reporter was under the control of synthetic promoters containing multiple specific binding sites for nuclear factor kappa B(NF-κB), activator protein-1(AP-1) or nuclear factor of activated T cells(NFAT). Chromatin immunoprecipitation(ChI P)assay was accomplished to detect the binding of NF-κB p65 subunit to the apoE promoter in HEK-293 treated with 500 μmol/L Hcy. As control, cells were incubated with similar concentration of cysteine. NF-κB p65 proteins bound to DNA were immunoprecipitated with anti-p65 antibodies and DNA was identified by PCR using primers amplifying the region-100/+4 of the apoE gene. RESULTS: RT-PCR revealed that high levels of Hcy(250-750 μmol/L) induced a 2-3 fold decrease in apoE m RNA levels in HEK-293 cells, while apo E gene expression was not significantly affected by treatment with lower concentrations of Hcy(100 μmol/L). Immunoblotting data provided additional evidence for the negative role of Hcy in apoE expression. Hcy decreased apoE promoter activity, in the presence or absence of ME2, in a dose dependent manner, in both RAW 264.7 and HEK-293 cells, as revealed by transient transfection experiments. The downstream effectors of the signaling pathways of Hcy were also investigated. The inhibitory effect of Hcy on the apo E promoter activity was counteracted by MAPK/ERK kinase 1/2(MEK1/2) inhibitor U0126, suggesting that MEK1/2 is involved in the downregulation of apoE promoter activity by Hcy. Our data demonstrated that Hcy-induced inhibition of apoE took place through activation of NF-κB. Moreover, we demonstrated that Hcy activated a synthetic promoter containing three NF-κB binding sites, but did not affect promoters containing AP-1 or NFAT binding sites. ChI P experiments revealed that NF-κB p65 subunit is recruited to the apoE promoter following Hcy treatment of cells.CONCLUSION: Hcy-induced stress negatively modulates apoE expression via MEK1/2 and NF-κB activation. The decreased apo E expression in peripheral tissues may aggravate atherosclerosis, neurodegenerative diseases and renal dysfunctions.

Effect of c-fos antisense probe on prostaglandin E_2-induced upregulation of vascular endothelial growth factor mRNA in human liver cancer cells

AIM: To examine the effect of prostaglandin E2 (PGE2) on the expression of vascular endothelial growth factor (VEGF) mRNA in the human hepatocellular carcinoma (HCC) HepG2 cells and the possible involvement of c-fos protein in this process.METHODS: Human HCC HepG2 cells were divided into three groups treated respectively with PGE2, a combination of PGE2 and c-fos antisense oligodeoxynucleotide (ASO),and PGE2 plus c-fos sense oligodeoxynudeotide (SO). The expression of VEGF mRNA in HepG2 cells after different treatments was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). The relative expression level of VEGF mRNA in HepG2 cells in each group was measured.RESULTS: Administration of PGE2 resulted in an increased expression of c-fosand VEGF mRNA in HepG2 cells. The relative expression level of c-fos mRNA reached the peak at 3 h (68.4±4.7%) after PGE2 treatment, which was significantly higher than that at 0 h (20.6±1.7%, P＜0.01).Whereas, the highest expression level of VEGF mRNA was observed at 6 h (100.5±6.1%) after PGE2 treatment, which was significantly higher than that at 0 h (33.2±2.4%,P＜0.01). C-fos ASO significantly reduced PGE2-induced VEGF mRNA expression in HepG2 cells.CONCLUSION: PGE2 increases the expression and secretion of VEGF in HCC cells by activating the transcription factor c-fos, promotes the angiogenesis of HCC and plays an important role in the pathogenesis of liver cancer.