肝组织中NF-κB、TGF-β1及其Ⅰ型受体mRNA和HSC在肝纤维化中的改变及护肝片对其的影响

目的探讨中、晚期纤维化大鼠肝组织中肝星状细胞(HSC)的活化与增殖、核转录因子-κB(NF-κB)及转化生长因子-β1(TGF-β1)及其Ⅰ型受体(TβRⅠ)表达的改变及护肝片对其的影响。方法采用12.5%CCl4诱导的大鼠肝纤维化模型,自造模之日起,大鼠分组灌胃给药(护肝片921mg/kg)或溶媒,每日一次,直至8或13周末,分别处死动物,取左叶肝组织石蜡包埋,制作组织芯片。免疫组化S-P法检测大鼠肝组织α-平滑肌肌动蛋白(-αSMA)和NF-κB p65蛋白的表达,原位杂交检测TGF-β1及TβRⅠmRNA的表达;并用MetaMorph图像分析系统计数-αSMA阳性细胞数,对NF-κB p65蛋白、TGF-β1及TβRⅠmRNA的表达量进行定量分析。结果 1.模型复制8周和13周,模型组的肝损伤及其纤维化分级均明显高于正常组(P<0.01),护肝片组的肝损伤及其纤维化分级均轻于模型组。2.模型复制8周和13周,模型组活化的HSC(即-αSMA阳性细胞)数量较正常组明显增多,NF-κB p65蛋白、TGF-β1及TβRⅠmRNA的表达均较正常组明显增强(P<0.01);3.护肝片显著抑制8、13周纤维化肝组织HSC的活化与增殖和NF-κB p65蛋白、TGF-β1及TβRⅠmRNA的表达(P<0.01)。结论抑制HSC的活化与增殖和NF-κB p65蛋白与TGF-β1及TβRⅠmRNA的表达可能是护肝片抗肝纤维化作用的靶点之一。     

dl-3-正丁基苯酞对脑损伤大鼠的神经保护作用的实验研究

目的:研究dl-3-正丁基苯酞(NBP)对脑损伤大鼠的神经保护作用。方法:将100只7周龄清洁级雄性Sprague-Dawley(SD)大鼠随机分成5组,分别为假手术组、模型组、NBP低、中和高剂量组,每组20只。使用控制性皮层撞击损伤建立中型大鼠颅脑损伤模型。将NBP溶解在大豆油中,NBP低、中和高剂量组分别按照每天20、40和80 mg/kg的剂量灌胃,假手术组和模型组灌胃等体积的大豆油,共给药2周。采用改良神经功能缺损评分(m NSS)对大鼠的神经系统状况进行评价。检测各组大鼠治疗后的脑组织含水量以及脑组织中丙二醛(MDA)、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)水平。TUNEL方法鉴定细胞的凋亡。通过RT-PCR、Western blot或免疫组化检测脑组织中Nrf2、NQO-1、HO-1、ApoJ、MMP9、AQP4、Caspase-3和AKT的表达。结果:NBP治疗2周后,NBP低、中和高剂量组大鼠的m NSS评分和神经元凋亡率以剂量依赖性方式显著降低(P0.05)。与模型组比较,NBP低、中和高剂量组大鼠的脑含水量均显著降低(P0.05)。与模型组比较,NBP低、中和高剂量组大鼠的MDA显著降低,而SOD和GSH-Px显著升高(P0.05)。与模型组比较,NBP低、中和高剂量组大鼠的细胞核Nrf2显著升高,而细胞质Nrf2显著降低(P0.05)。与模型组比较,NBP低、中和高剂量组大鼠的NQO-1和HO-1蛋白表达水平显著升高(P0.05)。与模型组比较,NBP低、中和高剂量组大鼠的AQP4、MMP-9、ApoJ和Caspase-3的m RNA和蛋白表达水平均显著降低,而AKT显著升高(P0.05)。结论:NBP对创伤性颅脑外伤大鼠具有一定的神经保护作用。     

血红素加氧酶-1对急性重症胰腺炎相关肺损伤TLR4/NF-κB通路的影响

目的:探讨血红素加氧酶-1(HO-1)对急性重症胰腺炎相关肺损伤(PALI)Toll样受体-4(TLR4)/核因子-κB(NF-κB)信号传导通路的影响。方法:32只SD大鼠随机分为Sham组、PALI组、HO-1促进剂组、HO-1抑制剂组,每组8只。PALI组经胆胰管注入牛磺胆酸钠制备急性重症胰腺炎(ANP)动物模型。Sham组胆胰管内不注入牛磺胆酸钠,其余操作同PALI组。HO-1促进剂组于造模后30 min经腹腔注射牛血晶素75μg/kg;HO-1抑制剂组于造模后30 min经腹腔注射锌-原卟啉20μmol/kg。PALI组和Sham组均于造模后30 min经腹腔注射等量生理盐水。各组大鼠术后24 h,进行肺损伤学评分,统计肺湿/干重比值。检测大鼠术后24 h血清淀粉酶、TNF-α、IL-6、NGAL水平。检测大鼠术后24 h肺组织中TLR4、NF-κB p65蛋白表达。结果:PALI组肺损伤学评分、肺湿/干重比值、淀粉酶、TNF-α、IL-6、NGAL、TLR4、NF-κB p65明显高于Sham组;HO-1促进剂组肺损伤学评分、肺湿/干重比值、淀粉酶、TNF-α、IL-6、NGAL、TLR4、NF-κB p65明显低于PALI组;HO-1抑制剂组肺损伤学评分、肺湿/干重比值、淀粉酶、TNF-α、IL-6、NGAL、TLR4、NF-κBp65明显高于PALI组;差异均有统计学意义(P<0.05)。结论:HO-1能够通过抑制TLR4/NF-κB信号通路的激活,下调TNF-α、IL-6、NGAL等炎症因子的释放,从而发挥减轻急性重症胰腺炎相关肺损伤的作用。     

姜黄素调控Nrf2信号通路改善运动性肾损伤大鼠肾脏细胞外基质沉积的机制研究

本文就姜黄素对运动性肾损伤大鼠Nrf2通路相关蛋白表达及细胞外基质沉积的影响进行了研究。SPF级雄性大鼠随机分为对照组(C组)、模型组(OL组)和姜黄素+模型组(COL组)。C组不进行运动干预,其他组进行6周递增负荷跑台训练,训练期间COL组灌胃姜黄素,其他组灌胃等体积羧甲基纤维素纳。训练结束后24 h,观察各组大鼠肾脏组织形态和超微结构,检测血液、肾脏组织相关生化指标。结果显示,肾脏组织形态,OL组较C组发生明显改变,肾小球淤血肿胀、系膜区增大; COL组肾小球略显肿胀,系膜区增大等情况明显改善。超微结构,OL组肾小球内血管结构扩张,基底膜厚度不均,间质细胞杂乱分散; COL组肾小球内皮层部分异常,间质细胞回缩。基质/肾小球面积比、血清Cor、SCr、BUN及肾脏TGF-β1、TNF-α、IL-1β、NF-κB,OL组较C组显著上升(P 0. 01),COL组显著下降(P 0. 05或P 0. 01);血清T及T/Cor、肾脏Nrf2、HO-1表达,OL组较C组显著下降(P 0. 05或P 0. 01),COL组显著上升(P 0. 05或P 0. 01)。从而说明,姜黄素可能通过调控过度训练大鼠肾脏Nrf2信号通路相关蛋白表达,抑制NF-κB通路活化及TGF-β1等相关炎症因子的分泌,改善肾小球ECM的过度沉积,保护肾脏结构与功能的正常。     

姜黄素对大鼠运动性心肌纤维化的保护作用

本文就姜黄素调控p38 MAPK/NF-κB信号通路对长时程、大强度运动致大鼠运动性心肌纤维化的保护作用进行了研究。SPF级雄性SD大鼠随机分为对照组(control group, C)、模型组(model group, M)、姜黄素+模型组(curcumin+model group, CM)。C组安静饲养,其余组进行6周递增负荷跑台训练。训练期间CM组灌胃姜黄素,其余组灌胃等体积0.5%羧甲基纤维素钠。训练后24 h取材,观察心肌组织形态与超微结构,检测血清、心肌相关生化指标。结果显示,心肌组织形态,M组较C组出现损伤性改变,心肌纤维出现断裂,且伴有炎症浸润、结缔组织增生现象,CM组较M组改善明显;心肌超微结构,M组线粒体嵴短缩,部分出现空泡变性,CM组无明显异常。与C组相比,M组心肌组织糖原容积分数、血清cTNI及心肌TGF-β1、TNF-α、IL-1β、p-p38 MAPK和NF-κB p65显著上升(P0.01);与M组相比,CM组心肌组织糖原容积分数、血清cTNI及心肌TGF-β1、TNF-α、IL-1β、p-p38 MAPK和NF-κB p65显著下降(P0.05或P0.01)。从而说明,姜黄素可能通过抑制p38 MAPK/NF-κB信号通路相关蛋白质过度活化和表达,调控心肌组织炎症因子合成与分泌及细胞外基质(extracellular matrix, ECM)合成与降解间的平衡,缓解心肌纤维化。     

帕瑞昔布对骨关节炎大鼠软骨细胞的影响*

目的:探究帕瑞昔布对骨关节炎大鼠软骨细胞形态、数量及TNF-α/NF-κB信号通路在其中的作用。方法:将所选取的大鼠随机分组,第一组,模型组(MO组):该组大鼠制作骨关节炎大鼠模型;第二组,假手术组(SS组):该组大鼠在骨关节做切口后不做任何处理;第三组,治疗组(TR组):该组大鼠制作骨关节炎模型后给予帕瑞昔布进行治疗,每组5只。通过cck-8法、Western blot法、qRT-PCR法、HE染色法、OARSI评分分别检测三组大鼠软骨细胞增殖情况、TNF-α/NF-κB的蛋白表达、TNF-α/NF-κB mRNA的表达水平、软骨组织病变程度。结果:与SS组大鼠比较,MO组和TR组关节软组织细胞增殖虽然均显著减少(P＜0.05),但TR组的增殖显著高于MO组。同样TR组的软骨组织结构好于MO组,OARSI评分显著低于MO组(P＜0.05);与SS组大鼠比较, MO组和TR组大鼠TNF-α和NF-κB的蛋白与基因表达水平虽然均显著高于SS组,但TR组的相应蛋白与基因表达水平显著低于MO组(P＜0.05)。结论:帕瑞昔布可能通过抑制TNF-α/NF-κB信号通路的表达对骨关节炎大鼠起到治疗作用。     

基于LIN28A/NF-κB信号通路研究狗肝菜多糖缓解肝纤维化的作用机制

探讨狗肝菜多糖(DCP)通过LIN28A/NF-κB信号通路改善大鼠肝纤维化(HF)。将60只雄性SD大鼠以每组10只,随机分成正常组、模型组、秋水仙素组和DCP低中高剂量(50、100、200 mg/kg)组。通过每周进行腹腔注射40%的四氯化碳(CCl 4)橄榄油溶液(1 mL/kg)2次,建立HF大鼠模型,正常组按照相同剂量注射橄榄油;每日根据体重给予秋水仙素组和DCP低中高剂量组大鼠相应的药物进行治疗,正常组与模型组大鼠按照相同计算方式灌胃蒸馏水,造模与治疗过程持续6周。实验终点,使用HE染色和Masson染色观察和评价大鼠肝脏组织病变程度;使用ELISA法检测大鼠血清中HA、LN、PC III、IV-C含量和肝脏组织中炎症因子(IL-1β、IL-6和TNF-α)水平;使用PCR和Western blot检测和分析大鼠肝脏组织中α-SMA、TGF-β1、LIN28A、NF-κBp65、MMP9、COX-2、iNOS的mRNA和蛋白表达水平。结果显示,秋水仙素和各剂量的DCP均可以降低大鼠血清中HA、LN、PC III和IV-C含量,且DCP高剂量组效果明显;病理结果显示,与模型组相比DCP组和秋水仙素组可以明显缓解大鼠肝脏的病变程度;肝脏组织中的α-SMA、TGF-β1、LIN28A、NF-κBp65、MMP9、COX-2和iNOS的表达均有不同程度的下降。综上所述,DCP对大鼠HF具有明显改善作用,其机制与抑制NF-κBp65蛋白表达,减少下游炎症因子的释放而发挥抗HF作用。     

莪术醇对非酒精性脂肪性肝大鼠肝功能和肝纤维化的影响及机制*

目的:探讨莪术醇(CC)对非酒精性脂肪性肝(NAFLD)大鼠模型肝功能和肝纤维化的影响及机制。方法:采用高脂饮食构建非酒精脂肪肝炎(NASH)伴肝纤维化的大鼠模型,将60只SD大鼠随机分为:空白对照组、模型组(NASH)、NASH+复方鳖甲软肝片(CBT)组(阳性对照组)、NASH+CC组(25、50、100 mg/kg),每组10只。测量大鼠肝脏占体重的百分比,测量大鼠高密度脂蛋白(HDL)、甘油三酯(TG)、谷丙转氨酶(ALT)、谷草转氨酶(AST)水平,HE染色观察肝纤维化情况,免疫组化检测鼠肝组织α-平滑肌肌动蛋白(α-SMA)表达及肝组织核因子κB p65(NF-κB p65)的阳性染色情况,蛋白印迹(Western blot)检测α-SMA、基质金属蛋白酶-1(MMP-1)、基质金属蛋白酶抑制剂-1(TIMP-1)蛋白表达及Toll样受体-4(TLR4)、转化生长因子激活激酶-1(TAK1)、NF-κB p65、血管细胞粘附分子-1(VCAM-1)蛋白的表达情况,酶联免疫吸附法(ELISA)检测肝组织中白介素(IL-6、IL-10、IL-1β)、肿瘤坏死因子-α(TNF-α)的表达。结果:与空白对照组相比,模型组大鼠HDL、 IL-10含量、MMP-1蛋白表达量显著降低(P＜0.05),TG、ALT、AST、肝组织P65阳性率,α-SMA、TIMP-1、TLR4、TAK1、NF-κB p65、VCAM-1表达、IL-6、TNF-α及IL-1β含量显著升高(P＜0.05)。与模型组相比,CBT和CC处理后大鼠HDL、 IL-10含量、MMP-1蛋白表达量显著升高(P＜0.05),TG、ALT、AST、肝组织P65阳性率,α-SMA、TIMP-1、TLR4、TAK1、NF-κB p65、VCAM-1表达、IL-6、TNF-α及IL-1β含量显著降低(P＜0.05),其中模型+CC组以高浓度组改善最显著(P＜0.05),但各剂量改善幅度均低于模型+CBT组(P＜0.05)。结论:莪术醇通过调节TLR4、TAK1、NF-κB p65信号通路,减轻炎症反应,改善肝功能,从而缓解非酒精性脂肪肝肝肝纤维化,且在一定范围内呈浓度依赖性。     

小蘖碱对异丙肾上腺素诱导大鼠心肌梗死的保护作用

摘要 目的：揭示小蘖碱（BER）对异丙肾上腺素（ISO）诱导大鼠心肌梗死的保护作用及机制。方法：将100只SD大鼠随机分为5组（n=20）：对照组、ISO组、ISO+10BER（BER 10 mg/kg/d）、ISO+20BER（BER 20 mg/kg/d）和ISO+50BER（BER 50 mg/kg/d）。给药组大鼠按照指定的剂量灌胃BER,对照组和ISO组灌胃等体积无菌水,共灌胃2周。然后,除对照组之外,其他组大鼠皮下注射ISO（5 mg/kg/d）,对照组皮下注射等体积的0.9%无菌盐水,连续3 d。通过超声心动图检查大鼠的EF、FS、LVEDD和LVESD;苏木精和伊红（HE）染色评价心肌组织形态学;Masson三色染色用于评估心脏的间质纤维化;2,3,5-氯化三苯基四氮唑（TTC）法检测心肌梗死体积。Western blot检测心肌组织中collagen I、collagen Ⅲ、TGF-β1、TNF-α、Smad3、p-Smad3、NF-κB、α-SMA、Nrf2、HO-1、Bcl-2、Bax和caspase-3的表达。免疫组化评估间隙连接蛋白43(Cx43)的表达。使用试剂盒检测血清SOD、CAT和MDA表达水平。结果：与ISO组相比,BER预处理组大鼠的心肌梗死体积和LVEDD和LVESD显著降低,而EF和FS显著升高（P<0.05）。BER预处理组大鼠的纤维化标志物（collagen I、collagen Ⅲ和α-SMA）表达水平与ISO组相比显著下调（P<0.05）。与ISO组相比,BER预处理组大鼠的TGF-β1/Smad3信号通路和炎症因子（TNF-α和NF-κB）被抑制。BER预处理组大鼠的Cx43阳性染色评分显著高于ISO组（P<0.05）。与ISO组相比,BER预处理组大鼠的促凋亡蛋白（Bax和caspase-3）被下调,而抗凋亡蛋白Bcl-2被上调（P<0.05）。与ISO组相比,BER预处理组大鼠的MDA水平显著降低,而SOD和CAT显著升高（P<0.05）。BER预处理组大鼠的Nrf2和HO-1水平显著高于ISO组（P<0.05）。结论：在异丙肾上腺素诱导的心肌梗死大鼠模型中,小檗碱预处理可通过抑制心脏纤维化、炎症反应、心肌细胞凋亡和氧化应激损伤来减少心肌梗死体积并改善心脏功能。     

Docosahexaenoic acid inhibition of inflammation is partially via cross-talk between Nrf2/heme oxygenase 1 and IKK/NF-κB pathways

We examined the underlying mechanisms involved in n-3 docosahexaenoic acid (DHA) inhibition of inflammation in EA.hy926 cells. The present results demonstrated that pretreatment with DHA (50 and 100 μM) inhibited tumor necrosis factor-alpha (TNF-α)-induced intercellular adhesion molecule 1 (ICAM-1) protein, mRNA expression and promoter activity. In addition, TNF-α-stimulated inhibitory kappa B (IκB) kinase (IKK) phosphorylation, IκB phosphorylation and degradation, p65 nuclear translocation, and nuclear factor-κB (NF-κB) and DNA binding activity were attenuated by pretreatment with DHA. DHA triggered early-stage and transient reactive oxygen species (ROS) generation and significantly increased the protein expression of heme oxygenase 1 (HO-1), induced nuclear factor erythroid 2-related factor 2 (Nrf2) translocation to the nucleus and up-regulated antioxidant response element (ARE)-luciferase reporter activity. Moreover, DHA inhibited Nrf2 ubiquitination and proteasome activity. DHA activated Akt, p38 and ERK1/2 phosphorylation, and specific inhibitors of respective pathways attenuated DHA-induced Nrf2 nuclear translocation and HO-1 expression. Transfection with HO-1 siRNA knocked down HO-1 expression and partially reversed the DHA-mediated inhibition of TNF-α-induced p65 nuclear translocation and ICAM-1 expression. Importantly, we show for the first time that HO-1 plays a down-regulatory role in NF-κB nuclear translocation, and inhibition of Nrf2 ubiquitination and proteasome activity are involved in increased cellular Nrf2 level by DHA. In this study, we show that HO-1 plays a down-regulatory role in NF-κB nuclear translocation and that the protective effect of DHA against inflammation is partially via up-regulation of Nrf2-mediated HO-1 expression and inhibition of IKK/NF-κB signaling pathway.     

Forsythiaside A Exhibits Anti-inflammatory Effects in LPS-Stimulated BV2 Microglia Cells Through Activation of Nrf2/HO-1 Signaling Pathway

Inflammation and oxidative stress have been reported to play critical roles in the pathogenesis of neurodegenerative disease. Forsythiaside A, a phenylethanoside product isolated from air-dried fruits of Forsythia suspensa, has been reported to have anti-inflammatory and antioxidant effects. In this study, the anti-inflammatory effects of forsythiaside A on LPS-stimulated BV2 microglia cells and primary microglia cells were investigated. The production of inflammatory mediators TNF-α, IL-1β, NO and PGE₂ were detected in this study. NF-κB, nuclear factor-erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) expression were detected by western blot analysis. Our results showed that forsythiaside A significantly inhibited LPS-induced inflammatory mediators TNF-α, IL-1β, NO and PGE₂ production. LPS-induced NF-κB activation was suppressed by forsythiaside A. Furthermore, forsythiaside A was found to up-regulate the expression of Nrf2 and HO-1. In conclusion, this study demonstrates that forsythiaside A inhibits LPS-induced inflammatory responses in BV2 microglia cells and primary microglia cells through inhibition of NF-κB activation and activation of Nrf2/HO-1 signaling pathway.     

Genipin Inhibits LPS-Induced Inflammatory Response in BV2 Microglial Cells

Genipin, an aglycon of geniposide, has been reported to have anti-inflammatory effect. However, the anti-inflammatory activity of genipin on LPS-stimulated BV2 microglial cells has not been reported. In this study, we investigated the molecular mechanisms responsible for the anti-inflammatory activity of genipin both in vivo and in vitro. The levels of TNF-α, IL-1β, NO and PGE₂ were detected by ELISA. The expression of Nrf2, HO-1, and NF-κB were detected by western blot analysis. In vivo, genipin significantly attenuated LPS-induced memory deficit in the Morris water maze and passive avoidance tasks. Genipin also inhibited LPS-induced TNF-α and IL-1β expression in brain tissues. In vitro, our results showed that genipin inhibited LPS-induced TNF-α, IL-1β, NO and PGE₂ production in a concentration-dependent manner. Genipin also suppressed LPS-induced NF-κB activation. In addition, the expression of Nrf2 and HO-1 were up-regulated by treatment of genipin. Furthermore, the inhibition of genipin on inflammatory mediator production was attenuated by transfection with Nrf2 siRNA. In conclusion, genipin inhibited LPS-induced inflammatory response by activating Nrf2 signaling pathway in BV2 microglia.     

Protective effects of rutin on liver injury induced by biliary obstruction in rats

Rutin has been shown to possess beneficial health effects, including hepatoprotection. However, to date, it has not been demonstrated to have a hepatoprotective effect against cholestatic liver injury. This is the first report to show a protective effect of rutin on cholestatic liver injury. Cholestasis was produced by bile duct ligation (BDL) in male Sprague–Dawley rats for 3 weeks. Daily oral administration of rutin was started 1 week before injury and was maintained for 4 weeks. In comparison with the control group, the BDL group showed liver injury as evidenced by histological changes and elevation in serum biochemicals, ductular reaction, fibrosis, inflammation, and oxidative stress. These pathophysiological changes were attenuated by rutin supplementation. Rutin alleviated BDL-induced transforming growth factor β1 (TGF-β1), interleukin-1β, connective tissue growth factor, and collagen expression. The antifibrotic effect of rutin was accompanied by reductions in α-smooth muscle actin-positive matrix-producing cells and Smad2/3 activity critical to the fibrogenic potential of TGF-β1. Rutin attenuated BDL-induced oxidative stress, leukocyte accumulation, NF-κB activation, and proinflammatory cytokine production. Further studies demonstrated an inhibitory effect of rutin on the redox-sensitive intracellular signaling molecule extracellular signal-regulated kinase (ERK). Rutin also attenuated BDL-induced reduction in NF-E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and AMP-activated protein kinase (AMPK). Taken together, the beneficial effects of rutin were shown to be associated with antioxidative and anti-inflammatory effects as well as the downregulation of NF-κB and TGF-β/Smad signaling, probably via interference of ERK activation and/or enhancement of Nrf2, HO-1, and AMPK activity.     

Suppression of NF-κB and NF-κB regulated oxidative stress and neuroinflammation by BAY 11-7082 (IκB phosphorylation inhibitor) in experimental diabetic neuropathy

Inflammation is an emerging patho-mechanism of diabetes and its complications. NF-κB pathway is one of the central machinery initiating and propagating inflammatory responses. The present study envisaged the involvement of NF-κB inflammatory cascade in the pathophysiology of diabetic neuropathy using BAY 11-7082, an IκB phosphorylation inhibitor. Streptozotocin was used to induce diabetes in Sprauge Dawley rats. BAY 11-7082 (1 &; 3 mg/kg) was administered to diabetic rats for 14 days starting from the end of six weeks post diabetic induction. Diabetic rats developed deficits in nerve functions and altered nociceptive parameters and also showed elevated expression of NF-κB (p65), IκB and p-IκB along with increased levels of IL-6 &; TNF-α and inducible enzymes (COX-2 and iNOS). Furthermore, there was an increase in oxidative stress and decrease in Nrf2/HO-1 expression. We observed that BAY 11-7082 alleviated abnormal sensory responses and deficits in nerve functions. BAY 11-7082 also ameliorated the increase in expression of NF-κB, IκB and p-IκB. BAY 11-7082 curbed down the levels of IL-6, TNF-α, COX-2 and iNOS in the sciatic nerve. Lowering of lipid peroxidation and improvement in GSH levels was also seen along with increased expression of Nrf2/HO-1. Thus it can be concluded that NF-κB expression and downstream expression of proinflammatory mediators are prominent features of nerve damage leading to inflammation and oxidative stress and BAY 11-7082 was able to ameliorate experimental diabetic neuropathy by modulating neuroinflammation and improving antioxidant defence.     

Downregulated microRNA-27b attenuates lipopolysaccharide-induced acute lung injury via activation of NF-E2-related factor 2 and inhibition of nuclear factor κB signaling pathway

Acute lung injury (ALI) is a life-threatening, diffuse heterogeneous lung injury characterized by acute onset, pulmonary edema, and respiratory failure. Lipopolysaccharide (LPS) is a leading cause for ALI and when administered to a mouse it induces a lung phenotype exhibiting some of the clinical characteristics of human ALI. This study focused on investigating whether microRNA-27b (miR-27b) affects ALI in a mouse model established by LPS-induction and to further explore the underlying mechanism. After model establishment, the mice were treated with miR-27b agomir, miR-27b antagomir, or D-ribofuranosylbenzimidazole (an inhibitor of nuclear factor-E2-related factor 2 [Nrf2]) to determine levels of miR-27b, Nrf2, nuclear factor kappa-light-chain-enhancer of activated B cells nuclear factor κB (NF-κB), p-NF-κB, and heme oxygenase-1 (HO-1). The levels of interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) in bronchoalveolar lavage fluid (BALF) were determined. The results of luciferase activity suggested that Nrf2 was a target gene of miR-27b. It was indicated that the Nrf2 level decreased in lung tissues from ALI mice. The downregulation of miR-27b decreased the levels of IL-1β, IL-6, and TNF-α in BALF of ALI mice. Downregulated miR-27b increased Nrf2 level, thus enhancing HO-1 level along with reduction of NF-κB level as well as the extent of NF-κB phosphorylation in the lung tissues of the transfected mice. Pathological changes were ameliorated in LPS-reduced mice elicited by miR-27b inhibition. The results of this study demonstrate that downregulated miR-27b couldenhance Nrf2 and HO-1 expressions, inhibit NF-κB signaling pathway, which exerts a protective effect on LPS-induced ALI in mice.     

Impaired TGF-β signaling and a defect in resolution of inflammation contribute to delayed wound healing in a female rat model of type 2 diabetes

Wound healing (WH) impairment is a well-documented phenomenon in clinical and experimental diabetes. Sex hormones, in addition to a number of signaling pathways including transforming growth factor-β1 (TGF-β1)/Smads and TNF-α/NF-κB in macrophages and fibroblasts, appear to play a cardinal role in determining the rate and nature of WH. We hypothesized that a defect in resolution of inflammation and an enhancement in TNF-α/NF-κB activity induced by estrogen deficiency contribute to the impairment of TGF-β signaling and delayed WH in diabetes models. Goto-Kakizaki (GK) rats and full thickness excisional wounds were used as models for type 2 diabetes (T2D) and WH, respectively. Parameters related to the various stages of WH were assessed using histomorphometry, western blotting, real-time PCR, immunofluorescence microscopy and ELISA-based assays. Retarded re-epithelialization, suppressed angiogenesis, delayed wound closure, reduced estrogen level and heightened states of oxidative stress were characteristic features of T2D wounds. These abnormalities were associated with a defect in resolution of inflammation, shifts in macrophage phenotypes, increased β3-integrin expression, impaired wound TGF-β1 signaling (↓p-Smad2/↑Smad7) and enhanced TNF-α/NFκB activity. Human/rat dermal fibroblasts of T2D, compared to corresponding control values, displayed resistance to TGF-β-mediated responses including cell migration, myofibroblast formation and p-Smad2 generation. A pegylated form of soluble TNF receptor-1 (PEG-sTNF-RI) or estrogen replacement therapy significantly improved re-epithelialization and wound contraction, enhanced TGFβ/Smad signaling, and polarized the differentiation of macrophages toward an M2 or "alternatively" activated phenotype, while limiting secondary inflammatory-mediated injury. Our data suggest that reduced estrogen levels and enhanced TNF-α/NF-κB activity delayed WH in T2D by attenuating TGFβ/Smad signaling and impairing the resolution of inflammation; most of these defects were ameliorated with estrogen and/or PEG-sTNF-RI therapy.