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.

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.

Sulforaphane enhances Nrf2-mediated antioxidant responses of skeletal muscle induced by exhaustive exercise in HIIT mice

Nuclear factor erythroid-derived 2-like 2(Nrf2)is the master regulator of antioxidant defenses.High-intensity interval training(HIIT)has been proposed as a time-efficient training program and has become a substantial component of modern training program In the present study,we evaluated the effects of sulforaphane(SFN),a dietary isothiocyanate derived from cruciferous vegetables and a potent Nrf2 activator,on Nrf2-mediated antioxidant defense responses of skeletal muscle induced by exhaustive exercise in HIIT mice.Male C57 BL/6 J mice were randomly allocated into control group,HIIT group,and HIIT pretreated with SFN(HIIT+SFN)group.On the third day after completion of a 6-weeks HIIT protocol,an exhaustive treadmill test was conducted in all mice.Mice were intraperitoneally injected with SFN(HIIT+SFN group)or PBS(HIIT and control mice)4 times in 3 days prior to the exhaustive treadmill test.The results indicated that the 6-weeks HIIT protocol did not increase the antioxidative capacity of skeletal muscle during exhaustive exercise.Importantly,SFN treatment improved anti oxidative capacity of skeletal muscle in response to the acute exhaustive exercise by increasing mRNA and nucleoprotein expression of Nrf2 and these genes involved in antioxidant generation and decreasing blood creatine kinase(CK)and 4-hydroxy-2-nonenal(4-HNE)-modified protein levels in the HIIT mice.

Rhamnus crenata leaf extracts exhibit anti-inflammatory activity via modulating the Nrf2/HO-1 and NF-κB/MAPK signaling pathways

Objective:To elucidate the potential anti-inflammatory mechanisms of Rhamnus crenata leaf extracts using RAW264.7 cells.Methods:We used 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay to measure cell viability.Nitric oxide(NO)production was measured using Griess reagent.Western blotting and RT-PCR assays were carried out for analyzing the protein and gene expressions of pro-inflammatory mediators,respectively.Moreover,PD98059(ERK1/2 inhibitor),SB203580(p38 inhibitor),SP600125(JNK inhibitor),and BAY11-7082(NF-κB inhibitor)were used to evaluate the anti-inflammatory mechanism of Rhamnus crenata leaf extract.Results:Rhamnus crenata leaf extracts significantly inhibited the production of the pro-inflammatory mediators such as NO,iNOS,COX-2,IL-1β,and TNF-αin lipopolysaccharide(LPS)-stimulated RAW264.7 cells.Rhamnus crenata leaf extracts also suppressed LPS-induced degradation of IκB-αand nuclear accumulation of p65,which resulted in the inhibition of NF-κB activation in RAW264.7 cells.Additionally,the extracts attenuated the phosphorylation of p38,ERK1/2,and JNK in LPS-stimulated RAW264.7 cells.Moreover,HO-1 expression induced by Rhamnus crenata leaf extracts was significantly downregulated by SB230580,PD98059,SP600125 and BAY11-7082.Conclusions:Rhamnus crenata leaf extract may upregulate HO-1 expression through inhibition of p38,ERK1/2,and NF-κB activation,which may contribute to the anti-inflammatory activity of the extracts.Rhamnus crenata leaf extracts may have great potential for the development of anti-inflammatory drugs to treat acute and chronic inflammatory diseases.

Nrf2-mediated ferroptosis of spermatogenic cells involved in male reproductive toxicity induced by polystyrene nanoplastics in mice

Microplastics(MPs)and nanoplastics(NPs)have become hazardous materials due to the massive amount of plastic waste and disposable masks,but their specific health effects remain uncertain.In this study,fluorescence-labeled polystyrene NPs(PS-NPs)were injected into the circulatory systems of mice to determine the distribution and potential toxic effects of NPs in vivo.Interestingly,whole-body imaging found that PS-NPs accumulated in the testes of mice.Therefore,the toxic effects of PS-NPs on the reproduction systems and the spermatocytes cell line of male mice,and their mechanisms,were investigated.After oral exposure to PS-NPs,their spermatogenesis was affected and the spermatogenic cells were damaged.The spermatocyte cell line GC-2 was exposed to PS-NPs and analyzed using RNA sequencing(RNA-seq)to determine the toxic mechanisms;a ferroptosis pathway was found after PS-NP exposure.The phenomena and indicators of ferroptosis were then determined and verified by ferroptosis inhibitor ferrostatin-1(Fer-1),and it was also found that nuclear factor erythroid 2-related factor 2(Nrf2)played an important role in spermatogenic cell ferroptosis induced by PS-NPs.Finally,it was confirmed in vivo that this mechanism of Nrf2 played a protective role in PS-NPs-induced male reproductive toxicity.This study demonstrated that PS-NPs induce male reproductive dysfunction in mice by causing spermatogenic cell ferroptosis dependent on Nrf2.

Engineered Bacillus subtilis alleviates intestinal oxidative injury through Nrf2-Keap1 pathway in enterotoxigenic Escherichia coli(ETEC) K88-infected piglet

Engineered probiotics can serve as therapeutics based on their ability of produce recombinant immune-stimulating properties.In this study,we built the recombinant Bacillus subtilis WB800 expressing antimicrobial peptide KR32(WB800-KR32)using genetic engineering methods and investigated its protective effects of nuclear factor-E2-related factor 2(Nrf2)-Kelch-like ECH-associated protein 1(Keap1)pathway activation in intestinal oxidative disturbance induced by enterotoxigenic Escherichia coli(ETEC)K88 in weaned piglets.Twenty-eight weaned piglets were randomly distributed into four treatment groups with seven replicates fed with a basal diet.The feed of the control group(CON)was infused with normal sterilized saline;meanwhile,the ETEC,ETEC+WB800,and ETEC+WB800-KR32 groups were orally administered normal sterilized saline,5×10^(10)CFU(CFU:colony forming units)WB800,and 5×10^(10)CFU WB800-KR32,respectively,on Days 1-14 and all infused with ETEC K881×10^(10)CFU on Days 15-17.The results showed that pretreatment with WB800-KR32 attenuated ETEC-induced intestinal disturbance,improved the mucosal activity of antioxidant enzyme(catalase(CAT),superoxide dismutase(SOD),and glutathione peroxidase(GPx))and decreased the content of malondialdehyde(MDA).More importantly,WB800-KR32 downregulated genes involved in antioxidant defense(GPx and SOD1).Interestingly,WB800-KR32 upregulated the protein expression of Nrf2 and downregulated the protein expression of Keap1 in the ileum.WB800-KR32 markedly changed the richness estimators(Ace and Chao)of gut microbiota and increased the abundance of Eubacterium_rectale_ATCC_33656 in the feces.The results suggested that WB800-KR32 may alleviate ETEC-induced intestinal oxidative injury through the Nrf2-Keap1 pathway,providing a new perspective for WB800-KR32 as potential therapeutics to regulate intestinal oxidative disturbance in ETEC K88 infection.

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.

川芎嗪激活核因子相关因子-2 (Nrf-2)抑制高脂饮食喂养的Apo-E基因敲除小鼠的动脉粥样硬化

目的观察川芎嗪能否通过激活核因子相关因子-2(nuclear factor E2-related factor 2,Nrf-2)从而减轻氧化应激所致的动脉粥样硬化损伤。方法 40只雄性载脂蛋白E(apolipoprotein-E,Apo-E)基因敲除小鼠随机分为4组,分别给予普通饮食+生理盐水腹腔注射(n=10)、高脂饮食+生理盐水腹腔注射(n=10)、高脂饮食+川芎嗪每天100mg/kg体重腹腔注射(n=10)、普通饮食+川芎嗪每天100mg/kg体重腹腔注射(n=10)。每天1次,持续8周,HE染色法观察主动脉粥样硬化改变,ELISA法检测血清和主动脉组织超氧化物歧化酶(superoxide dismutase,SOD)和谷胱甘肽S转移酶(glutathione S-transferase,GST)水平,Western blot法检测主动脉组织Nrf-2的蛋白表达,real-time PCR检测主动脉组织Nrf-2的mRNA表达。结果川芎嗪可显著降低高脂饮食喂养的Apo-E基因敲除小鼠主动脉斑块面积、内膜/中膜厚度比,增加血清和主动脉组织SOD和GST含量,增加主动脉组织中的总Nrf-2蛋白和核Nrf-2蛋白含量,增加Nrf-2mRNA相对表达量。结论川芎嗪通过促进Nrf-2mRNA的表达和核内转位,提高主动脉组织Nrf-2的因子浓度,进而促进下游各种抗氧化蛋白的表达,从而减轻氧化应激所致的动脉粥样硬化。

黄芪甲苷Ⅳ通过激活Nrf-2/HO-1信号通路抑制氧化应激介导的人SY5Y细胞凋亡

目的探讨黄芪甲苷Ⅳ(AST4)对H_(2)O_(2)诱导的人SY5Y细胞氧化应激损伤以及细胞凋亡的保护作用及机制。方法体外培养SY5Y细胞,用H_(2)O_(2)诱导建立氧化应激模型,分为PBS组、H_(2)O_(2)模型组和ASTⅣ组。采用四甲基偶氮唑蓝(MTT)法测定细胞活力,原位末端转移酶标记技术(TUNEL)检测细胞凋亡。取各组细胞的上清液,比色法测定丙二醛(MAD)、超氧化物歧化酶(SOD)和谷胱甘肽(GSH)的含量。免疫荧光细胞化学染色法检测裂解型胱天蛋白酶3(c-caspase-3)和核因子E2相关因子(Nrf-2)的表达和分布。Western blot法检测细胞凋亡蛋白B淋巴细胞瘤因子2(Bcl2)、Bcl2相关X蛋白(BAX)和ccaspase,以及氧化应激信号通路Nrf-2在胞质内和细胞核内的表达及下游蛋白血红素加氧酶1(HO-1)的蛋白水平。结果AST4对处于氧化应激损伤状态下的SY5Y细胞具有保护作用,能够减少MAD含量,增加GSH和SOD的含量。AST4增加Bcl2表达,减少BAX表达,Bc12/BAX的比值与H_(2)O_(2)模型组相比显著升高,同时抑制c-caspase的表达。AST4促进Nrf-2核转位,增加下游抗氧化蛋白HO-1的表达。结论AST4可通过激活Nrf-2/HO-1信号通路,促进Nrf-2核转位,增加HO-1的表达,调节氧化/抗氧化平衡,提高机体抗氧化水平,保护细胞免受氧化损伤和减少细胞凋亡。

CRISPR-Cas9-based genome-wide screening identified novel targets for treating sorafenib-resistant hepatocellular carcinoma:a cross-talk between FGF21 and the NRF2 pathway

The treatment of hepatocellular carcinoma(HCC)has been dominated by multikinase inhibitors for more than a decade.However,drug resistance can severely restrict the efficacy of these drugs.Using CRISPR/CAS9 genome library screening,we evaluated Kelch-like ECH-associated protein 1(KEAP1)as a key regulator of sorafenib’s susceptibility in HCC.We also investigated whether KEAP1’s knockdown can stabilize nuclear factor(erythroid-derived 2)-like 2(NRF2)protein levels that led to sorafenib’s resistance,including an NRF2 inhibitor that can synergize with sorafenib to abolish HCC’s growth in vitro and in vivo.Furthermore,we clarified that fibroblast growth factor 21(FGF21)is an important downstream regulator of NRF2 in HCC.Intriguingly,we observed that FGF21 bound to NRF2 through the C-terminus of FGF21,thereby stabilizing NRF2 by reducing its ubiquitination and generating a positive feedback loop in sorafenib-resistant HCC.These findings,therefore,propose that targeting FGF21 is a promising strategy to combat HCC sorafenib’s resistance.

Nrf2 Activation by Morinda citrifolia L. (Noni) Fruit Juices

Objective:The objective of the study was to identify Nrf2 activators from differently treated Morinda citrifolia L.fruit juices and their cytotoxicity.Materials and Methods:Noni fruit juices were prepared by different treatments:unripe(T1),ripe(T2),purchased(T3),and Noni juices fermented with Lactobacillus plantarum(T4).These extracts were tested for Nrf2 activation and nuclear factor kappa B(NF-κB)inhibition activities.These active extracts were further studied for their nuclear Nrf2 translocation and induction of HO-1 protein expression.Finally,the active extracts were purified using open column chromatography and RP-high pressure liquid chromatography(HPLC)techniques through bioassay-guided separation.Moreover,all Noni juice samples were tested for cytotoxicity using mammalian cell-based methylthiazoltetrazolium(MTT)assay.Results:Only purchased(T3)and ripe Noni fruit juices fermented with LP at 22℃(T4–22)showed strongest Nrf2 activation and NF-κB inhibitory activity.Further,these two extracts enhanced the nuclear accumulation of Nrf2 after 2 h and also promoted Nrf2 and HO-1 nuclear translocation.Induction of HO-1 gene expression of Hep G2/ARE cells treated with T3 confirmed that it is a potent inducer of the Nrf2 target gene HO-1.Bioassay-guided separation resulted in subfractions with high Nrf2 activity.The strongest Nrf2 active subfraction led to the identification of scopoletin as an Nrf2 activator.Moreover,none of the tested samples showed any cytotoxicity for the MTT assay.Conclusions:The presence of potential Nrf2 activators in the Noni fruit juices that were nontoxic in our MTT assay could mitigate the production of harmful reactive species in the biological systems,and thereby,could helpful in alleviating and prevention of chronic diseases.

20C,a new bibenzyl compound,plays a significant role in rotenone-induced oxidative insult

20C,a bibenzyl compound isolated from Gastrodia elata,possesses antioxidative properties in PC12 cells,but its in-depth molecular mechanisms against rotenone-induced neurotoxicity remains unknown.Recent studies indicate that without intact DJ-1,nuclear factor erythroid 2-related factor(Nrf2)protein becomes unstable,and the activity of Nrf2-mediated downstream antioxidant enzymes are thereby suppressed.Therefore,increasing the nuclear translocation of Nrf2 by DJ-1 may present a helpful means for the prevention and treatment of chronic diseases related to oxidative stress.Our results showed that 20C clearly protected PC12 and SH-SY5Y cells against rotenone-induced oxidative injury in a concentration-dependent manner.Furthermore,20C markedly up-regulated the levels of DJ-1,which in turn activated phosphoinositide-3-kinase(PI3K)/Akt signaling and inhibited glycogen synthase kinase 3β(GSK3β)activation,eventually promoting Nrf2 nuclear translocation and inducing the expression of Nrf2-mediated downstream antioxidative enzymes such as HO-1.The antioxidative effects of 20C could be partially blocked by ShR NA-mediated knockdown of DJ-1 and inhibition of the PI3K/Akt pathways with Akt1/2 kinase inhibitor in PC12 and SH-SY5Y cells,respectively.Conclusively,our findings confirm that DJ-1 is necessary for 20C-mediated protection against rotenone-induced oxidative damage,at least in part,by activating PI3K/Akt signaling,and subsequently enhancing the nuclear accumulation of Nrf2.The findings from our investigation suggest that 20C should be developed as a novel candidate for preventing or alleviating the consequences of PD in the future.

原子因素的角色(导出 erythroid 2 ) 在新陈代谢的动态平衡和胰岛素行动喜欢 2 : 为糖尿病处理的一个新奇机会？

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 in? ammation, aging and cancer. Thus, the capacity of endogenous free radical clearance can be of patho-physiological importance; in this regard, the major reactive oxy- gen species defense machinery, the nuclear factor (erythroid-derived 2)-like 2 (Nrf2) system needs to beprecisely 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.

磷酸锰铁锂通过Keap1/Nrf 2信号通路影响雄性小鼠生殖系统

目的探讨磷酸锰铁锂(LiMnFePO_(4))可否通过Keap1/Nrf 2信号通路影响雄性小鼠的生殖系统。方法将18只8周龄C57BL/6J小鼠随机分为对照组和低、高剂量(5、50 mg/kg)LiMnFePO_(4)组,每组6只,灌胃染毒6周处死。取出睾丸,称取小鼠体质量并计算睾丸和附睾脏器系数、精子计数和精子畸形率,检测小鼠睾丸组织丙二醛(MDA)、超氧化物歧化酶(SOD)活性水平,观察睾丸组织形态,测定小鼠睾丸组织Kelch样环氧氯丙烷相关蛋白-1(Keap1)和核因子红细胞2相关因子2(Nrf 2)、血红素氧合酶1(HO-1)的蛋白和mRNA表达水平。结果LiMnFePO_(4)暴露对小鼠体质量、睾丸和附睾脏器系数影响差异无统计学意义;LiMnFePO_(4)染毒小鼠睾丸组织SOD活性水平降低,MDA水平升高;小鼠睾丸组织Keap1的蛋白和mRNA表达水平升高,HO-1的蛋白和mRNA表达水平降低,Nrf 2的蛋白表达水平降低、mRNA表达水平升高;高剂量LiMnFePO_(4)染毒小鼠睾丸组织精子计数减少,精子畸形率上升,睾丸曲细精管皱缩,管内精细胞减少、排列混乱,睾丸间质细胞增生。结论LiMnFePO_(4)可能通过Keap1/Nrf 2信号通路影响小鼠睾丸组织氧化应激状况,导致雄性小鼠生殖毒性。

Reversal of doxorubicin resistance in lung cancer cells by neferine is explained by nuclear factor erythroid-derived 2-like 2 mediated lung resistance protein down regulation

Aim:Development of multi drug resistance and dose limiting cardiotoxicity are hindering the use of Doxorubicin(Dox)in clinical settings.Augmented dox efflux induced by lung resistance protein(LRP)over expression has been related to multi drug resistance phenotype in various cancers.An alkaloid from lotus,Neferine(Nef)shows both anticancer and cardioprotective effects.Here,we have investigated the interconnection between nuclear factor erythroid-derived 2-like 2(NRF2)and LRP in Dox resistance and how Nef can overcome Dox resistance in lung cancer cells by altering this signaling.Methods:Anti-proliferative and apoptotic-inducing effects of Nef and Dox combination in Parental and Dox resistant lung cancer cells were determined in monolayers and 3D spheroids.Intracellular Dox was analyzed using flow cytometry,siRNA knockdown and western blot analysis were used to elucidate NRF2-LRP crosstalk mechanism.

白花丹素调控Nrf-2/Keap1信号通路诱导膀胱癌细胞铁死亡

目的:探讨白花丹素作为一种新型的铁死亡诱导剂在膀胱癌抑制中的作用机制。方法:本研究中使用了膀胱癌细胞T24。采用细胞增殖与活性检测-8(CCK-8)法检测白花丹素(0.1、1、2、3、6、12、24、48μmol·L^(-1))对T24细胞活力的影响。采用膜联蛋白V-异硫氰酸荧光素/碘化丙啶(Annexin V FITC/PI)凋亡试剂盒检测白花丹素(1.5、3、6μmol·L^(-1))对T24细胞凋亡的影响。采用不同的抑制剂(铁死亡抑制剂Fer-1,凋亡抑制剂VAD,坏死性凋亡抑制剂Nec-1)与白花丹素(6μmol·L^(-1))联合使用。采用活性氧荧光探针(DCFH-DA),丙二醛(MDA)和谷胱甘肽(GSH)试剂盒分别检测不同浓度的白花丹素(1.5、3、6μmol·L^(-1))对T24细胞内活性氧水平,MDA和GSH的含量,脂质过氧化荧光探针(C11-BODIPY)荧光探针检测白花丹素(1.5、3、6μmol·L^(-1))对T24细胞中过氧化物水平的影响。蛋白免疫印迹法(Western blot)检测白花丹素(1.5、3、6μmol·L^(-1))细胞中溶质载体家族7成员11(SLC7A11)、谷胱甘肽过氧化酶(GPX4)、核因子E2相关因子-2(Nrf-2)和Kelch样ECH关联蛋白1(Keap1)的蛋白表达的影响。结果:与空白组比较,白花丹素组T24细胞的活性明显降低(P<0.05),IC50为3.52μmol·L^(-1)。与空白组比较,白花丹素组(1.5、3、6μmol·L^(-1))T24细胞凋亡率明显升高(P<0.05);与单独使用6μmol·L^(-1)的白花丹素组比较,铁死亡抑制剂和凋亡抑制剂组能够逆转6μmol·L^(-1)的白花丹素对T24细胞增殖抑制作用(P<0.05)。与空白组比较,白花丹素组(1.5、3、6μmol·L^(-1)),T24细胞ROS、MDA及脂质过氧化物的含量明显升高,GSH水平明显降低,铁死亡相关蛋白SLC7A11、GPX4以及Nrf-2/Keap1明显降低(P<0.05)。结论:白花丹素能诱导细胞铁死亡,其机制与Nrf-2/Keap1信号通路有关。

核因子红细胞2相关因子2在毒死蜱毒性机制中的作用

毒死蜱(chlorpyrifos,CPF)是一种广泛使用的有机磷农药,其对人类健康和生态系统的潜在风险已引起广泛关注。CPF主要通过抑制乙酰胆碱酯酶(AChE)发挥杀虫作用,但越来越多的研究表明,CPF的毒性作用远不止于此,也与氧化应激、炎症反应、细胞死亡等多种生物学过程密切相关,因而可能导致神经退行性疾病、生殖发育障碍以及其他慢性健康问题。核因子红细胞2相关因子2(Nrf 2)作为一种关键的抗氧化应激调节因子,具有显著的保护作用。本文旨在综述Nrf 2在调节CPF诱导的氧化应激、神经毒性、细胞死亡和炎症反应中的作用机制,探讨其作为潜在治疗靶点的前景,以为开发新的CPF中毒治疗策略提供理论基础。

Biochanin A attenuates spinal cord injury in rats during early stages by inhibiting oxidative stress and inflammasome activation

Previous studies have shown that Biochanin A,a flavonoid compound with estrogenic effects,can serve as a neuroprotective agent in the context of cerebral ischemia/reperfusion injury;howeve r,its effect on spinal cord injury is still unclea r. In this study,a rat model of spinal cord injury was established using the heavy o bject impact method,and the rats were then treated with Biochanin A(40 mg/kg) via intrape ritoneal injection for 14 consecutive days.The res ults showed that Biochanin A effectively alleviated spinal cord neuronal injury and spinal co rd tissue injury,reduced inflammation and oxidative stress in spinal cord neuro ns,and reduced apoptosis and pyroptosis.In addition,Biochanin A inhibited the expression of inflammasome-related proteins(ASC,NLRP3,and GSDMD)and the Toll-like receptor 4/nuclear factor-κB pathway,activated the Nrf2/heme oxygenase 1 signaling pathway,and increased the expression of the autophagy markers LC3 Ⅱ,Beclin-1,and P62.Moreove r,the therapeutic effects of Biochanin A on early post-s pinal cord injury were similar to those of methylprednisolone.These findings suggest that Biochanin A protected neurons in the injured spinal cord through the Toll-like receptor 4/nuclear factor κB and Nrf2/heme oxygenase 1 signaling pathways.These findings suggest that Biochanin A can alleviate post-spinal cord injury at an early stage.

α-亚麻酸和花生四烯酸对Nrf 2和Ⅰ相代谢酶CYP7A1表达的影响

为了检测α-亚麻酸(α-linolenic acid,ALA)和花生四烯酸(arachidonic acid,AA)对于人肝癌细胞系(HepG2细胞)中核转录因子Nrf 2和Ⅰ相代谢酶胆固醇7α-羟化酶(CYP7A1)的mRNA和蛋白质表达的影响,并探究CYP7A1是否受Nrf 2的调控,试验以不同浓度的ALA和AA诱导HepG2细胞24 h,之后采用Real-time PCR法和Western-blot法分别检测HepG2细胞内Nrf 2和CYP7A1的mRNA和蛋白质的表达量。结果表明:当使ALA浓度为0.25,0.5,1 mmol/L作用于HepG2细胞时,Nrf 2和CYP7A1的mRNA和蛋白质的表达量相比于细胞对照均呈剂量依赖性升高(P<0.01);当使AA浓度为0.25,0.5,1 mmol/L作用于HepG2细胞时,Nrf 2的mRNA和蛋白质的表达量相比于细胞对照呈剂量依赖性升高(P<0.01),但CYP7A1的mRNA和蛋白质的表达量相比于细胞对照则呈剂量依赖性减少(P<0.01)。说明不同剂量的ALA和AA对Nrf 2和CYP7A1的mRNA和蛋白质的表达量影响不同,Nrf 2和CYP7A1呈正相关或负相关。