Semaphorin 7A impairs barrier function in cultured human corneal epithelial cells in a manner dependent on nuclear factor-kappa B

●AIM:To evaluate the role of semaphorin 7A(Sema7A)and its associated regulatory mechanisms in modulating the barrier function of cultured human corneal epithelial cells(HCEs).●METHODS:Barrier models of HCEs were treated with recombinant human Sema7A at concentrations of 0,125,250,or 500 ng/mL for 24,48,or 72h in vitro.Transepithelial electrical resistance(TEER)as well as Dextran-fluorescein isothiocyanate(FITC)permeability assays were conducted to assess barrier function.To quantify tight junctions(TJs)such as occludin and zonula occludens-1(ZO-1)at the mRNA level,reverse transcriptionpolymerase chain reaction(RT-PCR)analysis was performed.Immunoblotting was used to examine the activity of the nuclear factor-kappa B(NF-κB)signaling pathway and the production of TJs proteins.Immunofluorescence analyses were employed to localize the TJs.Enzyme-linked immunosorbent assay(ELISA)and RT-PCR were utilized to observe changes in interleukin(IL)-1βlevels.To investigate the role of NF-κB signaling activation and IL^(-1)βin Sema7A’s anti-barrier mechanism,we employed 0.1μmol/L IκB kinase 2(IKK2)inhibitor IV or 500 ng/mL IL^(-1)receptor(IL-1R)antagonist.●RESULTS:Treatment with Sema7A resulted in decreased TEER and increased permeability of Dextran-FITC in HCEs through down-regulating mRNA and protein levels of TJs in a time-and dose-dependent manner,as well as altering the localization of TJs.Furthermore,Sema7A stimulated the activation of inhibitor of kappa B alpha(IκBα)and expression of IL-1β.The anti-barrier function of Sema7A was significantly suppressed by treatment with IKK2 inhibitor IV or IL-1R antagonists.●CONCLUSION:Sema7A disrupts barrier function through its influence on NF-κB-mediated expression of TJ proteins,as well as the expression of IL-1β.These findings suggest that Sema7A could be a potential therapeutic target for the diseases in corneal epithelium.

茯苓甘草合剂辅助西药对慢性阻塞性肺疾病合并肌肉衰减患者NF-κB信号通路的影响

目的探讨茯苓甘草合剂辅助西药对慢性阻塞性肺疾病(COPD)合并肌肉衰减NF-κB信号通路的影响及分子机制。方法选取2020年8月至2022年8月COPD合并肌肉衰减患者104例,作为研究对象随机数字表法分为对照组和观察组,每组52例。对照组给予西药治疗,观察组给予西药+茯苓甘草合剂治疗。统计2组中医疗效、不良反应及治疗前后中医证候积分、NF-κB mRNA、蛋白及因子[白细胞介素-8(IL-8)、白细胞介素-1(IL-1)、肿瘤坏死因子-α(TNF-α)]、营养状况指标[转铁蛋白(Tf)、血红蛋白(Hb)、白蛋白(ALB)]、肌肉衰减相关指标[握力试验、起立-行走计时测试(TUGT)、5次坐立试验(FTSST)、肌少症筛查问卷(SARC-F)]。结果观察组中医治疗总有效率[86.54%(45/52)]高于对照组[67.31%(35/52)](P<0.05);治疗1个月、3个月后观察组中医证候积分低于对照组(P<0.05);治疗1个月、3个月后观察组NF-κB mRNA、NF-κB蛋白、IL-8、IL-1、TNF-α低于对照组(P<0.05);治疗3个月后观察组握力高于对照组,FTSST、TUGT、SARC-F评分低于对照组(P<0.05);治疗期间,2组均未出现明显不良反应。结论茯苓甘草合剂辅助西药治疗COPD合并肌肉衰减效果确切,可通过抑制NF-κB信号通路,减轻炎性反应,改善患者营养状态,有效改善临床症状,且安全性高。

Apigenin ameliorates imiquimod-induced psoriasis in C57BL/6J mice by inactivating STAT3 and NF-κB

Psoriasis is a chronic autoimmune disease featured by patches on the skin.It is caused by malfunction of immune cells and keratinocytes with inflammation as one of its key features.Apigenin(API)is a natural flavonoid with anti-inflammatory and immunoregulatory properties.Therefore,we speculated that API can ameliorate psoriasis,and determined its effect on the development of psoriasis by using imiquimod(IMQ)-induced psoriasis mouse model.Our results showed that API attenuated IMQ-induced phenotypic changes,such as erythema,scaling and epidermal thickening,and improved splenic hyperplasia.Abnormal differentiation of immune cells was restored in API-treated mice.Mechanistically,we revealed that API is a key regulator of signal transducer activator of transcription 3(STAT3).API regulated immune responses by reducing interleukin-23(IL-23)/STAT3/IL-17A axis.Moreover,it suppressed IMQ-caused cell hyperproliferation by inactivating STAT3 through regulation of extracellular signal-regulated kinase 1/2 and nuclear factor-κB(NF-κB)pathway.Furthermore,API reduced expression of inflammatory cytokines through inactivation of NF-κB.Taken together,our study demonstrates that API can ameliorate psoriasis and may be considered as a strategy for psoriasis treatment.

Jianpi Gushen Huayu decoction ameliorated diabetic nephropathy through modulating metabolites in kidney,and inhibiting TLR4/NF-κB/NLRP3 and JNK/P38 pathways

BACKGROUND Jianpi Gushen Huayu Decoction(JPGS)has been used to clinically treat diabetic nephropathy(DN)for many years.However,the protective mechanism of JPGS in treating DN remains unclear.AIM To evaluate the therapeutic effects and the possible mechanism of JPGS on DN.METHODS We first evaluated the therapeutic potential of JPGS on a DN mouse model.We then investigated the effect of JPGS on the renal metabolite levels of DN mice using non-targeted metabolomics.Furthermore,we examined the effects of JPGS on c-Jun N-terminal kinase(JNK)/P38-mediated apoptosis and the inflammatory responses mediated by toll-like receptor 4(TLR4)/nuclear factor-kappa B(NF-κB)/NOD-like receptor family pyrin domain containing 3(NLRP3).RESULTS The ameliorative effects of JPGS on DN mice included the alleviation of renal injury and the control of inflammation and oxidative stress.Untargeted metabolomic analysis revealed that JPGS altered the metabolites of the kidneys in DN mice.A total of 51 differential metabolites were screened.Pathway analysis results indicated that nine pathways significantly changed between the control and model groups,while six pathways significantly altered between the model and JPGS groups.Pathways related to cysteine and methionine metabolism;alanine,tryptophan metabolism;aspartate and glutamate metabolism;and riboflavin metabolism were identified as the key pathways through which JPGS affects DN.Further experimental validation showed that JPGS treatment reduced the expression of TLR4/NF-κB/NLRP3 pathways and JNK/P38 pathway-mediated apoptosis related factors.CONCLUSION JPGS could markedly treat mice with streptozotocin(STZ)-induced DN,which is possibly related to the regulation of several metabolic pathways found in kidneys.Furthermore,JPGS could improve kidney inflammatory responses and ameliorate kidney injuries in DN mice via the TLR4/NF-κB/NLRP3 pathway and inhibit JNK/P38 pathwaymediated apoptosis in DN mice.

地佐辛靶向TLR4/NF-κB信号通路减轻瑞芬太尼诱导的痛觉过敏机制研究

目的探讨地佐辛对瑞芬太尼诱导的痛觉过敏的影响及机制。方法将40只健康雄性SD大鼠,随机分为对照组(C组)、切口痛组(I组)、瑞芬太尼输注+切口痛组(R+I组)、瑞芬太尼联合地佐辛输注+切口痛组(R+D+I组),每组10只。其中,C组不做任何处理。R+I组和R+D+I组于造模前静脉输注瑞芬太尼,I组输注等量0.9%氯化钠溶液。随后,基于左后足底切口术对I组、R+I组和R+D+I组大鼠建立切口痛模型。R+D+I组大鼠在瑞芬太尼输注前通过尾静脉注射给予地佐辛预处理。采用痛觉行为学实验评估大鼠在术前和术后不同时间点的机械缩足反应阈(paw withdrawal threshold,PWT)和热缩足反应潜伏期(paw withdrawal latency,PWL);酶联免疫吸附(enzyme-linked immunosorbent assay,ELISA)检测4组大鼠脊髓背角相关炎性因子肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)及IL-10的表达水平;实时荧光定量PCR(quantitative real-time PCR,qRT-PCR)检测4组大鼠脊髓背角TLR4、NF-κB和TRPA1的mRNA表达水平;Western blot检测组大鼠脊髓背角TLR4、NF-κB和TRPA1的蛋白表达水平。结果成功构建瑞芬太尼诱导的大鼠术后痛觉过敏模型,与C组比较,I组在术后PWT值和PWL值均显著降低,脊髓背角促炎因子TNF-α、和IL-1β表达升高,而抗炎因子IL-10表达降低,TLR4、NF-κB、TRPA1蛋白和mRNA水平均明显增加(P<0.05);与I组比较,R+I组在术后PWT值和PWL值均明显下降,脊髓背角促炎因子TNF-α、和IL-1β表达升高,而抗炎因子IL-10表达降低以及TLR4、NF-κB、TRPA1蛋白和mRNA水平均明显增加(P<0.05);与R+I组比,R+D+I组在术后PWT值和PWL值均明显升高,脊髓背角促炎因子TNF-α、和IL-1β表达降低,而抗炎因子IL-10表达升高以及TLR4、NF-κB、TRPA1蛋白和mRNA水平均明显降低(P<0.05)。结论地佐辛通过抑制TLR4/NF-κB信号通路,下调TRPA1蛋白和mRNA表达,减少脊髓背角炎症,达到减轻瑞芬太尼诱导的术后痛觉过敏的效果。

泼尼松联合阿奇霉素序贯疗法治疗儿童重症肺炎支原体肺炎的疗效及对血清TLR4/MyD88/NF-κB信号通路相关蛋白和下游炎性因子水平的影响

目的探讨泼尼松联合阿奇霉素序贯疗法治疗儿童重症肺炎支原体肺炎的疗效及对血清Toll样受体4(TLR4)/髓样分化因子88(MyD88)/核因子κB(NF-κB)信号通路相关蛋白和下游炎性因子水平的影响。方法招募2019年1月至2022年6月唐山市妇幼保健院收治的儿童重症肺炎支原体肺炎患者120例,采用随机数字表法将其分为对照组(采用阿奇霉素治疗,60例)和观察组(采用泼尼松联合阿奇霉素治疗,60例)。治疗4周后,比较两组治疗效果、临床肺部感染量表(CIPS)评分、TLR4/MyD88/NF-κB信号通路相关蛋白以及下游炎性因子的水平。结果观察组患者的体温恢复时间、咳嗽缓解时间、咳痰缓解时间、喘息缓解时间、肺部啰音消失时间较对照组更快,住院时间更短,差异有统计学意义(P<0.05)。治疗后,两组的体温、白细胞计数、气道分泌物、氧合情况、胸部X射线、痰培养等CIPS项目评分以及总分均较治疗前降低,且观察组评分较对照组更低,差异有统计学意义(P<0.05)。治疗后,两组TLR4、MyD88、NF-κB、C-反应蛋白(CRP)、白细胞介素-6(IL-6)、降钙素原(PCT)水平均降低,且观察组水平较对照组更低,差异有统计学意义(P<0.05)。结论泼尼松联合阿奇霉素序贯疗法对人体血清TLR4/MyD88/NF-κB信号通路相关蛋白及下游炎性因子水平有显著下调作用,可提高儿童重症肺炎支原体肺炎患者的临床疗效。

乌司他丁抑制TLR4/NF-κB信号通路对心肺复苏大鼠心功能的改善作用

目的旨在探究乌司他丁对心肺复苏大鼠的影响。方法通过窒息构建心脏骤停大鼠模型,窒息9.5 min后,对大鼠静脉注射肾上腺素,并对大鼠胸部进行按压以实施心肺复苏。Kaplan-Meier存活曲线分析大鼠存活率,神经系统缺损评分(NDS)评估大鼠神经系统缺损,转棒疲劳实验评估大鼠运动协调及平衡能力。ELISA法检测血清炎性因子白细胞介素-1β(IL-1β)、肿瘤坏死因子(TNF-α)、IL-6水平,western blotting检测大脑皮层TLR4/NF-κB信号通路的表达。结果乌司他丁治疗提高大鼠存活率,改善心脏骤停后的心功能及大鼠神经认知功能、运动协调能力。乌司他丁降低心脏骤停/心肺复苏后促炎因子TNF-α、IL-1β、IL-6水平,降低TLR4蛋白及p-p65/p65水平。结论乌司他丁抑制TLR4/NF-κB通路活性,对心肺复苏大鼠心功能及运动协调能力具有改善作用。

优化溃结方对溃疡性结肠炎大鼠结肠Toll样受体/髓样分化因子88/核转录因子κB信号通路的影响

目的观察优化溃结方对溃疡性结肠炎(UC)大鼠结肠Toll样受体/髓样分化因子88/核转录因子κB(TLR/MyD88/NF-κB)信号通路的影响。方法将40只雄性SD大鼠随机分为空白组、模型组、优化溃结方组、柳氮磺吡啶组,每组10只。除空白组外,其余3组均参考三硝基苯磺酸(TNBS)/乙醇二次致炎法结合束缚法建立UC气滞血瘀型大鼠模型。造模成功后优化溃结方组大鼠予优化溃结方药液1.674 g/(kg·d)灌胃,柳氮磺吡啶组大鼠予柳氮磺吡啶药液0.54 g/(kg·d)灌胃,空白组、模型组不予任何治疗。14天后检测各组大鼠血清白细胞介素17A(IL-17A)、IL-10、IL-22水平,结肠组织MyD88、TLR2、TLR4、NF-κB p65蛋白和mRNA表达水平。结果与空白组相比,模型组血清IL-17A、IL-22水平显著升高(P<0.05),IL-10水平显著下降(P<0.05);与模型组相比,优化溃结方组、柳氮磺吡啶组IL-17A、IL-22水平显著降低(P<0.05),IL-10水平显著升高(P<0.05);优化溃结方组IL-17A、IL-22、IL-10水平与柳氮磺吡啶组比较差异无统计学意义(P>0.05)。与空白组相比,模型组结肠组织MyD88、TLR2、TLR4、NF-κB p65蛋白和mRNA表达均显著增加(P<0.05);与模型组相比,柳氮磺吡啶组、优化溃结方组MyD88、TLR2、TLR4、NF-κB p65蛋白和mRNA表达均显著下降(P<0.05);优化溃结方组MyD88、TLR2、TLR4、NF-κB p65蛋白和mRNA表达与柳氮磺吡啶组比较差异均无统计学意义(P>0.05)。结论优化溃结方可能通过调节TLR/MyD88/NF-κB信号通路,降低炎症因子水平,减轻炎症反应,修复结肠组织的超微结构,从而修复UC大鼠结肠黏膜屏障功能。

中药单体调控NF-κB信号通路治疗宫颈癌的研究进展

宫颈癌是女性生殖系统中发病率较高的恶性肿瘤,人乳头瘤病毒(HPV)持续感染是导致宫颈癌变的主要因素。NF-κB作为肿瘤相关炎症信号通路,在调节机体炎症反应与免疫应答方面发挥重要作用。HPV感染可激活NF-κB信号通路以促进宫颈慢性炎症,从而参与宫颈癌的发生发展。随着中医药的不断发展,中药在治疗肿瘤方面发挥了独特优势,中药单体能多靶点、多通路干预肿瘤细胞生长。通过多个中英文数据库的检索,发现中药单体可通过调控NF-κB信号通路发挥抑制宫颈癌细胞增殖、侵袭和转移、促进癌细胞凋亡、诱导癌细胞自噬、增强癌细胞化疗敏感性等作用以干预宫颈癌的发展。因此基于研究现状,本文从分子生物学角度全面论述中药单体调控NF-κB信号通路治疗宫颈癌的研究进展,以期为中医药靶向治疗宫颈癌的研究提供重要方向。

平喘宁调节IRE-1α-XBP-1s信号轴干预哮喘大鼠气道炎症的机制研究

目的:探究平喘宁对哮喘大鼠气道炎症的防治作用及机制。方法:将105只雄性SD大鼠按随机数字表法分为正常组、模型组、地塞米松组、桂龙咳喘宁组、平喘宁高剂量组、平喘宁中剂量组、平喘宁低剂量组,每组15只。以卵清蛋白联合氢氧化铝复制大鼠哮喘模型,造模21 d后,各给药组分别灌胃给予相应药物,正常组、模型组灌胃给予等体积的生理盐水,1次/d,连续4周。4周后,在进行哮喘激发试验后2 h内解剖大鼠并取出肺组织,收集支气管肺泡灌洗液(BALF)。HE染色观察肺组织中平滑肌厚度、炎症细胞浸润程度等相应病理的改变;ELISA法检测BALF中IL-5、IL-17水平;RT-qPCR法检测肺组织IRE-1αmRNA、XBP-1s mRNA、NF-κB p65 mRNA、Hgsnat mRNA、Pdgfrb mRNA、Scara3 mRNA相对表达量;Western blotting法检测肺组织中IRE-1α、XBP-1s、NF-κB p65蛋白相对表达量。结果:HE染色结果显示,与模型组比较,各给药组(平喘宁低剂量组、平喘宁中剂量组、平喘宁高剂量组、地塞米松组、桂龙咳喘宁组)大鼠肺组织病理情况都有不同程度的缓解。ELISA结果显示,与正常组比较,模型组大鼠BALF中IL-5、IL-17水平均明显升高(P<0.01);与模型组比较,各给药组大鼠BALF中IL-5、IL-17水平均明显降低(P<0.01),且平喘宁具有剂量依赖性;平喘宁低、中剂量组大鼠BALF中IL-5、IL-17水平均高于地塞米松组和桂龙咳喘宁组(P<0.01);平喘宁高剂量组大鼠BALF中IL-5水平明显高于地塞米松组和桂龙咳喘宁组(P<0.01),而IL-17水平与地塞米松组和桂龙咳喘宁组比较,差异无统计学意义(P>0.05)。RT-qPCR结果显示,与正常组比较,模型组大鼠肺组织IRE-1αmRNA、XBP-1s mRNA、NF-κB p65 mRNA相对表达量均明显升高(P<0.01),Hgsnat mRNA、Pdgfrb mRNA、Scara3 mRNA相对表达量均明显降低(P<0.01);与模型组比较,各给药组大鼠肺组织IRE-1αmRNA、XBP-1s mRNA、NF-κB p65 mRNA相对表达量均明显降低(P<0.01),Hgsnat mRNA、Pdgfrb mRNA、Scara3 mRNA相对表达量均明显升高(P<0.05或P<0.01);平喘宁低剂量组大鼠肺组织IRE-1αmRNA、XBP-1s mRNA、NF-κB p65 mRNA相对表达量均明显高于地塞米松组和桂龙咳喘宁组(P<0.01),Hgsnat mRNA、Pdgfrb mRNA、Scara3 mRNA相对表达量均明显低于地塞米松组和桂龙咳喘宁组(P<0.01);平喘宁中剂量组大鼠肺组织XBP-1s mRNA、NF-κB p65 mRNA相对表达量均明显高于地塞米松组和桂龙咳喘宁组(P<0.01),Hgsnat mRNA、Pdgfrb mRNA、Scara3 mRNA相对表达量均明显低于地塞米松组和桂龙咳喘宁组(P<0.05或P<0.01),而IRE-1αmRNA相对表达量与地塞米松组和桂龙咳喘宁组比较,差异无统计学意义(P>0.05);平喘宁高剂量组大鼠肺组织IRE-1αmRNA相对表达量均明显低于地塞米松组和桂龙咳喘宁组(P<0.01),而Hgsnat mRNA、Pdgfrb mRNA相对表达量均明显高于地塞米松组(P<0.01);平喘宁高剂量组Hgsnat mRNA、Pdgfrb mRNA相对表达量与桂龙咳喘宁组比较,差异无统计学意义(P>0.05),XBP-1s mRNA、NF-κB p65 mRNA、Scara3 mRNA与地塞米松组和桂龙咳喘宁组比较,差异无统计学意义(P>0.05)。Western blotting结果显示,与正常组比较,模型组大鼠肺组织IRE-1α、XBP-1s、NF-κB p65蛋白相对表达量均明显升高(P<0.01);与模型组比较,各给药组大鼠肺组织IRE-1α、XBP-1s、NF-κB p65蛋白相对表达量均明显降低(P<0.01);平喘宁低剂量组大鼠肺组织IRE-1α、XBP-1s、NF-κB p65蛋白相对表达量均明显高于地塞米松组和桂龙咳喘宁组(P<0.01);平喘宁中剂量组大鼠肺组织XBP-1s、NF-κB p65蛋白相对表达量均明显高于地塞米松组和桂龙咳喘宁组(P<0.05或P<0.01),IRE-1α蛋白相对表达量明显高于桂龙咳喘宁组(P<0.05),而IRE-1α蛋白相对表达量与地塞米松组比较,差异无统计学意义(P>0.05);平喘宁高剂量组大鼠肺组织IRE-1α、XBP-1s、NF-κB p65蛋白相对表达量与地塞米松组和桂龙咳喘宁组比较,差异无统计学意义(P>0.05)。结论:平喘宁可通过调节IRE-1α-XBP-1s信号轴改善OVA诱导的哮喘大鼠气道炎症性损伤。

Ketogenic diet alleviates cognitive dysfunction and neuroinflammation in APP/PS1 mice via the Nrf2/HO-1 and NF-κB signaling pathways

Alzheimer's disease is a progressive neurological disorder characterized by cognitive decline and chronic inflammation within the brain.The ketogenic diet,a widely recognized therapeutic intervention for refractory epilepsy,has recently been proposed as a potential treatment for a variety of neurological diseases,including Alzheimer's disease.However,the efficacy of ketogenic diet in treating Alzheimer's disease and the underlying mechanism remains unclear.The current investigation aimed to explore the effect of ketogenic diet on cognitive function and the underlying biological mechanisms in a mouse model of Alzheimer's disease.Male amyloid precursor protein/presenilin 1(APP/PS1)mice were randomly assigned to either a ketogenic diet or control diet group,and received their respective diets for a duration of 3 months.The findings show that ketogenic diet administration enhanced cognitive function,attenuated amyloid plaque formation and proinflammatory cytokine levels in APP/PS1 mice,and augmented the nuclear factor-erythroid 2-p45 derived factor 2/heme oxygenase-1 signaling pathway while suppressing the nuclear factor-kappa B pathway.Collectively,these data suggest that ketogenic diet may have a therapeutic potential in treating Alzheimer's disease by ameliorating the neurotoxicity associated with Aβ-induced inflammation.This study highlights the urgent need for further research into the use of ketogenic diet as a potential therapy for Alzheimer's disease.

Delayed hepatocarcinogenesis through antiangiogenic intervention in the nuclear factor-kappa B activation pathway in rats

BACKGROUND: The active form of nuclear factor-kappa B (NF-kappa B) is involved in the initiation, generation, and development of hepatocellular carcinoma (HCC), and is up-regulated in inflammation-associated malignancies. We investigated the dynamic expression of NF-kappa B and its influences on the occurrence of HCC through antiangiogenic (thalidomide) intervention in NF-kappa B activation. METHODS : Hepatoma models were induced with 2-fluorenylacetamide (2-FAA, 0.05%) in male Sprague-Dawley rats, and thalidomide (100 mg/kg body weight) was administered intragastrically to intervene in NF-kappa B activation. The pathological changes in the liver of sacrificed rats were assessed after hematoxylin and eosin staining. NF-kappa B mRNA was amplified by RT-nested PCR. The alterations of NF-kappa B and vascular endothelial growth factor (VEGF) expression were analyzed by enzyme-linked immunosorbent assay, immunohistochemistry, and Western blotting. RESULTS: Rat hepatocytes showed denatured, precancerous, and cancerous stages in hepatocarcinogenesis, with an increasing tendency of hepatic NF-kappa B, NF-kappa B mRNA, and VEGF expression, and their values in the HCC group were higher than those in controls (P<0.001). In the thalidomide-treated group, the morphologic changes generated only punctiform denaturation and necrosis at the early or middle stages, and nodular hyperplasia or a little atypical hyperplasia at the final stages, with the expression of NF-kappa B (chi(2)=9.93, P<0.001) and VEGF (chi(2)=8.024, P<0.001) lower than that in the 2-FAA group. CONCLUSION: NF-kappa B is overexpressed in hepatocarcinogenesis and antiangiogenic treatment down-regulates the expression of NF-kappa B and VEGF, and delays the occurrence of HCC. (Hepatobiliary Pancreat Dis Int 2010; 9: 169-174)

Urinary trypsin inhibitor attenuates hepatic ischemia-reperfusion injury by reducing nuclear factor-kappa B activation

BACKGROUND: Urinary trypsin inhibitor (UTI) inhibits the inflammatory response and protects against ischemia-reperfusion (I/R) injury. The inflammatory response is mediated by nuclear factor-kappa B (NF-kappa B) and its related target genes and products such as vascular endothelial cell adhesion molecule and CXC chemokines. We aimed to assess the roles of those mediators in a UTI-treated mouse model of hepatic I/R injury. METHODS: Treatment group 1 (UTI given 5 minutes prior to liver ischemia), treatment group 2 (UTI given 5 minutes after the anhepatic phase) and a control group were investigated. Blood and liver samples were obtained and compared at 1, 3, 6 and 24 hours after reperfusion. RESULTS: Attenuation of pathological hepatocellular damage was greater in the treatment groups than in the control group (P < 0.05). Compared with the control group, the UTI treatment groups showed significantly lower serum alanine aminotransferase and aspartate aminotransferase levels, decreased myeloperoxidase activity, and reduced NF-kappa B activation. Also downregulated was the expression of tumor necrosis factor-alpha, cytokine-induced neutrophil chemoattractant, and macrophage inflammatory protein-2 at the mRNA level. P-selectin protein and intercellular adhesion molecule-1 protein expression were also downregulated. In addition, the treatment group I showed a better protective effect against I/R injury than the treatment group 2. CONCLUSIONS: UTI reduces NF-kappa B activation and downregulates the expression of its related mediators, followed by the inhibition of neutrophil aggregation and infiltration in hepatic I/R injury. The protective role of UTI is more effective in prevention than in treatment.

Heme oxygenase-1 prevents liver fibrosis in rats by regulating the expression of PPAR_γ and NF-_κB

AIM:To investigate the effects of heme oxygenase(HO)-1 on liver fibrosis and the expression of peroxisome proliferator-activated receptor gamma(PPARγ) and nuclear factor-kappa B(NF-κB) in rats.METHODS:Sixty Wistar rats were used to construct liver fibrosis models and were randomly divided into 5 groups:group A(normal,untreated),group B(model for 4 wk,untreated),group C(model for 6 wk,untreated),group D [model for 6 wk,treated with zinc protoporphyrin Ⅸ(ZnPP-Ⅸ) from week 4 to week 6],group E(model for 6 wk,treated with hemin from week 4 to week 6).Next,liver injury was assessed by measuring serum alanine aminotransferase(ALT),aspartate aminotransferase(AST) and albumin levels.The degree of hepatic fibrosis was evaluated by measuring serum hyaluronate acid(HA),type Ⅳ collagen(Ⅳ-C) and by histological examination.Hydroxyproline(Hyp) content in the liver homogenate was determined.The expres-sion levels of alpha-smooth muscle actin(α-SMA) in liver tissue were measured by real-time quantitative polymerase chain reaction(RT-PCR).The expression levels of PPARγ and NF-κB were determined by RT-PCR and Western blotting.RESULTS:The expression of HO-1 increased with the development of fibrosis.Induction of HO-1 by hemin significantly attenuated the severity of liver injury and the levels of liver fibrosis as compared with inhibition of HO-1 by ZnPP-Ⅸ.The concentrations of serum ALT,AST,HA and Ⅳ-C in group E decreased compared with group C and group D(P < 0.01).Amount of Hyp and α-SMA in the liver tissues in group E decreased compared with group C(0.62 ± 0.14 vs 0.84 ± 0.07,1.42 ± 0.17 vs 1.84 ± 0.17,respectively,P < 0.01) and group D(0.62 ± 0.14 vs 1.11 ± 0.16,1.42 ± 0.17 vs 2.56 ± 0.37,respectively,P < 0.01).The expression of PPARγ at levels of transcription and translation decreased with the development of fibrosis especially in group D;and it increased in group E compared with groups C and D(0.88 ± 0.15 vs 0.56 ± 0.19,0.88 ± 0.15 vs 0.41 ± 0.11,respectively,P < 0.01).The expression of NF-κB increased with the development of fibrosis especially in group D;and it decreased in group E compared with groups C and D(1.43 ± 0.31 vs 1.89 ± 0.29,1.43 ± 0.31 vs 2.53 ± 0.54,respectively,P < 0.01).CONCLUSION:Our data demonstrate a potential mechanism that HO-1 can prevent liver fibrosis by enhancing the expression of PPARγ and decreasing the expression of NF-κB in liver tissues.

Characteristics of hepatic nuclear-transcription factor-kappa B expression and quantitative analysis in rat hepatocarcinogenesis

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. We analyzed the expression of miclear-transcription factor-kappa B (NF-kappa B) during hepatocarcinogenesis in order to evaluate its dynamic expression and its clinical value in the development and diagnosis of HCC. METHODS: Hepatoma models were induced by oral administration of 2-acetamidoflurene (2-FAA) to male Sprague-Dawley rats. Morphological changes were observed after hematoxylin and eosin staining. The cellular distribution of NF-kappa B expression during different stages of cancer development was investigated by immunohistochemistry, and the level of NF-kappa B expression in liver tissues was quantitatively analyzed by ELISA. The gene fragments of hepatic NF-kappa B were amplified by nested-polymerase chain reaction assay. RESULTS: Hepatocytes showed vacuole-like degeneration during the early stages, then had a hyperplastic nodal appearance during the middle stages, and finally progressed to tubercles of cancerous nests with high differentiation. The NF-kappa B-positive material was buff-colored, fine particles localized in the nucleus, and the incidence of NF-kappa B-positive cells was 81.8% in degeneration, 83.3% in precancerous lesions, and 100% in cancerous tissues. All of these values were higher than those in controls (P<0.01). Hepatic NF-kappa B expression and hepatic NF-kappa B-mRNA were also higher during the course of HCC development (P<0.01). CONCLUSION: The NF-kappa B signal transduction pathway is activated during the early stages of HCC development, and its abnormal expression may be associated with the occurrence of HCC.

Dietary saturated fatty acid and polyunsaturated fatty acid oppositely affect hepatic NOD-like receptor protein 3 inflammasome through regulating nuclear factor-kappa B activation

AIM: To investigate the effect of different dietary fatty acids on hepatic inflammasome activation.METHODS: Wild-type C57BL/6 mice were fed either a high-fat diet or polyunsaturated fatty acid (PUFA)-enriched diet. Primary hepatocytes were treated with either saturated fatty acids (SFAs) or PUFAs as well as combined with lipopolysaccharide (LPS). The expression of NOD-like receptor protein 3 (NLRP3) inflammasome, peroxisome proliferator-activated receptor-&#x003b3; and nuclear factor-kappa B (NF-&#x003ba;B) was determined by real-time PCR and Western blot. The activity of Caspase-1 and interleukine-1&#x003b2; production were measured.RESULTS: High-fat diet-induced hepatic steatosis was sufficient to induce and activate hepatic NLRP3 inflammasome. SFA palmitic acid (PA) directly activated NLRP3 inflammasome and increased sensitization to LPS-induced inflammasome activation in hepatocytes. In contrast, PUFA docosahexaenoic acid (DHA) had the potential to inhibit NLRP3 inflammasome expression in hepatocytes and partly abolished LPS-induced NLRP3 inflammasome activation. Furthermore, a high-fat diet increased but PUFA-enriched diet decreased sensitization to LPS-induced hepatic NLRP3 inflammasome activation in vivo. Moreover, PA increased but DHA decreased phosphorylated NF-&#x003ba;B p65 protein expression in hepatocytes.CONCLUSION: Hepatic NLRP3 inflammasome activation played an important role in the development of non-alcoholic fatty liver disease. Dietary SFAs and PUFAs oppositely regulated the activity of NLRP3 inflammasome through direct activation or inhibition of NF-&#x003ba;B.

EFFECT OF OXIDIZED-LDL ON NF-κB NUCLEAR TRANSLOCATION IN AORTIC SMOOTH MUSCLE CELLS ORIGINATED FROM RATS OF DIFFERENT AGES

Objective To investigate the molecular mechanism of atherosclerosis that related to age. Methods Immunohistochemistry staining and Western blot were adopted to determine the nuclear translocation of nuclear factor-kappa B (NF-κB) and expression of platelet-derived growth factor B (PDGF-B) in smooth muscle cells (SMCs) co-cultured with low density lipoprotein (LDL), oxidized LDL (ox-LDL), and ox-LDL+high density lipoprotein (HDL) originated from rats of 2 and 10 months old respectively. Fat stain was used to identify the lipid intake in SMCs. Results The optimal stimulation time of ox-LDL to SMCs was 12 hours. NF-κB intensity increased in most nuclei of SMCs that originated from rats of either 2 or 10 months old co-cultured with ox-LDL. The intensity of NF-κB and the amount of intracellular lipid taken in SMCs were more obvious in cells from 10-month-old rats than from the younger ones. Change of PDGF-B expression in SMCs was not remarkable in each group of rats. Conclusions The 10-month-old rats are more susceptive to ox-LDL than 2-month-old rats in activating nuclear transloca- tion of NF-κB. Maybe this is one of the important reasons contributing to the difference between the older and younger rats on the initiation and development of atherosclerosis lesion. Expression of PDGF-B is not associated with the activity of nuclear translocation of NF-κB.

Testosterone alleviates tumor necrosis factor-alpha-mediated tissue factor pathway inhibitor downregulation via suppression of nuclear factor-kappa B in endothelial cells

We have observed earlier that testosterone at physiological concentrations can stimulate tissue factor pathway inhibitor(TFPI)gene expression through the androgen receptor in endothelial cells.This study further investigated the impact of testosterone on TFPI levels in response to inflammatory cytokine tumor necrosis factor-alpha(TNF-α).Cultured human umbilical vein endothelial cells were incubated in the presence or absence of testosterone or TNF-α.TFPI protein and mRNA levels were assessed by enzyme-linked immunosorbent assay and quantitative real-time reverse transcription polymerase chain reaction.To study the cellular mechanism of testosterone’s action,nuclear factor-kappa B(NF-κB)translocation was confirmed by electrophoretic mobility shift assays.We found that after NF-κB was activated by TNF-α,TFPI protein levels declined significantly by 37.3%compared with controls(P<0.001),and the mRNA levels of TFPI also decreased greatly(P<0.001).A concentration of 30 nmol L-1 testosterone increased the secretion of TFPI compared with the TNF-α-treated group.NF-κB DNA-binding activity was significantly suppressed by testosterone(P<0.05).This suggests that physiological testosterone concentrations may exert their antithrombotic effects on TFPI expression during inflammation by downregulating NF-κB activity.

Inhibitory effects of Shuanghuanglian injection on nuclear factor-kappa B expression in mice with viral encephalitis in a time-and dose-dependent manner

Previous studies have confirmed that the anti-virus effects of Shuanghuanglian injection may be associated with nuclear factor-kappa B activity. This study observed nuclear factor-kappa B expression in mice with viral encephalitis, and showed significant decreases in nuclear factor-kappa B protein and mRNA levels following Shuanghuanglian injection. The inhibitory effect was more significant with prolonged intervention duration and increased treatment dose. These findings verify that Shuanghuanglian injection plays a therapeutic role in viral encephalitis by reducing expression of nuclear factor-kappa B in a time- and dose-dependent manner.

Shuanghuanglian injection downregulates nuclear factor-kappa B expression in mice with viral encephalitis

A mouse model of viral encephalitis was induced by intracranial injection of a Coxsackie virus B3 suspension. Quantitative real-time reverse transcription-PCR and western blot assay were applied to detect mRNA and protein expression of intelectin-2 and nuclear factor-kappa B in the viral encephalitis and control groups. Nuclear factor-kappa B and intelectin-2 mRNA and protein expression were significantly increased in mice with viral encephalitis. After intraperitoneal injection of Shuanghuanglian at a dose of 1.5 mg/kg for 5 successive days, intelectin-2 and nuclear factor-kappa B protein and mRNA expression were significantly decreased. To elucidate the relationship between intelectin-2 and nuclear factor-kappa B, mice with viral encephalitis were administered an intracerebral injection of 107 pfu recombinant lentivirus expressing intelectin shRNA. Both protein and mRNA levels of intelectin and nuclear factor-kappa B in brain tissue of mice were significantly decreased. Experimental findings suggest that Shuanghuanglian injection may downregulate nuclear factor-kappa B production via suppression of intelectin production, thus inhibiting inflammation associated with viral encephalitis.