柠檬酸钠对肾缺血再灌注损伤模型小鼠肾损伤指标及炎症细胞因子的影响

目的:揭示柠檬酸钠对肾缺血再灌注损伤模型小鼠肾损伤指标及炎症细胞因子的影响.方法:将40只C57BL/6小鼠随机分为假手术组(n=10)、模型组(n=10)、低剂量组(n=10)和高剂量组(n=10).建立缺血再灌注损伤模型前7 d,低剂量组和高剂量组分别以200 mg/kg和600 mg/kg的柠檬酸钠对小鼠进行灌胃...     

异丙酚和氯胺酮减轻大鼠肾缺血再灌注损伤

目的:观察异丙酚(propofol)或氯胺酮(ketamine)对缺血再灌注肾损伤(IR)大鼠肾组织病理变化的影响。方法:48只成年Wistar大鼠随机均分成6组,每组8只,分别为假手术组(S组)、缺血再灌注模型组(R组)、小剂量异丙酚(5mg/kg)组(P1组)、大剂量异丙酚(10mg/kg)组(P2组)、小剂量氯胺酮(10mg/kg)组(K1组)、大剂量氯胺酮(20mg/kg)组(K2组)。输液后72h处死所有大鼠,在实验开始及处死大鼠前取4mL静脉血放入低温冰箱中保存待测。处死大鼠后取部分肾脏组织置于甲醛及戊二醛溶液,用于石蜡切片,光镜及电镜观察肾脏组织结构的变化。另取一部分肾组织制作成肾组织匀浆待测。待测指标包括血肌酐(Scr)、血尿素氮(BUN)、丙二醛(MDA)、超氧化物歧化酶(SOD)。结果:与缺血再灌注模型组相比,异丙酚和氯胺酮能显著降低缺血再灌注肾损伤大鼠肾组织中MDA含量(P0.05),增强SOD活性(P0.05),使缺血再灌注肾损伤大鼠肾功能及组织学改变得到明显改善。结论:异丙酚或氯胺酮对肾缺血再灌注损伤有明显拮抗作用,其作用机制可能与药物抗氧化及抗炎作用有关。     

乙酸镁对大鼠心肌缺血-再灌注损伤的保护作用

目的 观察乙酸镁对心肌缺血-再灌注损伤过程中心肌保护作用及其机理.方法 取50只SD大鼠随机分为5组:假手术组(Sham),模型对照组(control),乙酸镁低剂量组(50mg/kg)、乙酸镁中剂量组(70mg/kg)、乙酸镁高剂量组(100mg/kg).采用整体大鼠心肌缺血-再灌注损伤模型,结扎冠状动脉左前降支30min后,再灌注60min,测定心肌组织SOD活性、MDA含量及血清中LDH和钱离子含量;观察ADP诱导的血小板聚集功能的变化.结果 与模型组相比,乙酸镁三个不同剂量组血中Mg2 浓度升高,LDH和MDA含量明显降低,SOD活性显著升高;抑制ADP诱导的血小板聚集,以上作用都呈剂量依赖性.结论 乙酸镁对大鼠心肌缺血再灌注损伤有保护作用,其机制与抗ADP诱导的血小板聚集,减轻氧自由基损伤.改善心肌细胞能量代谢有关.     

灯盏细辛对肺缺血-再灌注损伤时核转录因子κB表达的影响

目的:探讨灯盏细辛对肺缺血-再灌注(1/R)损伤时核转录因子-κB(NF-κB)表达的影响.方法:建立大鼠在体肺原位I/R损伤模型,将32只大鼠随机分为假手术组(Ⅰ组)、缺血-再灌注组(Ⅱ组)、小剂量灯盏细辛组(25mg/kg,Ⅲ组)、大剂量灯盏细辛组(50mg/kg,Ⅳ组);观察各组肺湿干重比(W/D),检测各组肺组织髓质过氧化物酶(MPO)活性,应用免疫组化及Western blotting法检测肺细胞核内NF-κB活性及含量,光镜下HE染色观察病理形态学改变、电镜观察肺组织超微结构变化.结果:Ⅲ、Ⅳ组W/D、MPO活性及细胞核内NF-κB含量均明显低于Ⅱ组,肺水肿程度及肺超微结构损害显著轻于Ⅱ组;Ⅲ、Ⅳ组之间比较差异显著(P<0.05).结论:灯盏细辛对肺缺血-再灌注损伤具有防治作用,其机制可能与其抑制NF-κB活化,从而减少中性粒细胞浸润、抑制炎症损伤有关.     

小鼠脑缺血时自噬相关基因5的抗损伤作用

 目的: 观察自噬相关基因5(Atg5)在小鼠脑缺血再灌注损伤中的抗损伤作用。方法: 将雄性BALB/c小鼠随机分为假手术(sham)组、缺血再灌注(I/R)组、Atg5 siRNA组和control siRNA组。I/R组采用大脑中动脉阻塞(MCAO)60 min后再灌注24 h。Atg5 siRNA组和control siRNA组将5 μL Atg5 siRNA或scrambled siRNA在MCAO前24 h侧脑室注射。实时荧光定量PCR和Western blot检测Atg5的表达;2,3,5-氯化三苯基四氮唑(TTC)染色法检测抑制Atg5对缺血再灌注损伤后脑梗死面积和水肿率的影响;神经行为学评分法检测抑制Atg5对缺血再灌注损伤后神经症状的影响。结果: MCAO后再灌24 h,缺血半影区Atg5 mRNA和蛋白水平显著增高(P<0.05);Atg5 siRNA明显降低缺血再灌后Atg5 mRNA和蛋白的表达(P<0.05);侧脑室给予Atg5 siRNA能显著增加脑梗死面积和水肿率,并加重神经行为学损伤(P<0.05)。结论: 沉默Atg5加重小鼠脑缺血再灌损伤,提示MCAO后诱导的 Atg5 可减轻小鼠局灶性脑缺血再灌注损伤。     

Panax notoginseng saponins reduces damage and inhibits apoptosis in lung ischemia reperfusion injury of rabbits

目的 探讨细胞凋亡与肺缺血再灌注损伤的关系以及三七总皂甙的作用及机制.方法 健康日本大耳白兔84只,随机分为对照组、肺缺血再灌注1、3、5h组和相应三七总皂甙干预组.复制肺缺血再灌注损伤模型.用原位缺口末端标记(TUNEL)法、聚丙烯酰胺凝胶电泳观测肺组织细胞凋亡,原位杂交技术检测肺组织细胞Fas/FasL系统和caspase-3基因表达.结果肺缺血再灌注组肺组织细胞凋亡指数(肺缺血再灌注5h组:22.08±1.93;对照组:2.04±0.67)、Fas/FasL和aspase 基因表达(肺缺血再灌注5h组:0.241 *0.029;对照组:0.121 ±0.015)均显著高于对照组(P＜0.01),并出现电泳梯形条带结构;三七总皂甙干预组Fas/FasL mRNA及其caspase-3的表达(三七总皂甙干预5 h组:0.199 ±0.020;肺缺血再灌注5h组:0.241 ±0.029)显著低于缺血再灌注组(P＜0.01),肺组织细胞凋亡指数(三七总皂甙干预5h组:12.58±1.82;肺缺血再灌注5h组:22.08±1.93)也显著低于缺血再灌注组(P＜0.01),梯形条带结构基本消失.肺组织细胞凋亡指数分别与caspace mRNA及Fas/FasL mRNA之间均呈显著正相关(P＜0.01).结论 三七总皂甙可能通过抑制Fas/FasL系统的激活,阻遏肺组织细胞凋亡,从而减轻肺缺血再灌注损伤.     

阿魏酸川芎嗪对缺血再灌注大鼠心肌细胞凋亡及凋亡相关蛋白表达的影响

 目的：观察阿魏酸川芎嗪对缺血再灌注损伤大鼠心肌细胞凋亡的影响,并探讨其可能机制。方法：将60只雄性SD大鼠随机分成5组：（1）假手术组;（2）缺血再灌注组;（3）川芎嗪(4 mg/kg)组;（4）阿魏酸川芎嗪低剂量(4 mg/kg)组;（5）阿魏酸川芎嗪高剂量(8 mg/kg)组。采用结扎左冠状动脉前降支30 min、再灌注120 min的方法复制大鼠心肌缺血再灌注模型;各组大鼠于再灌注前10 min分别颈静脉注射给药,于再灌注结束后,进行血清生化及心肌组织学检测。结果：阿魏酸川芎嗪能显著降低心肌缺血再灌注损伤大鼠血清中肌酸激酶同功酶、乳酸脱氢酶、心肌钙蛋白I和丙二醛的水平,提高总超氧化物歧化酶活性,增加心肌Bcl-2蛋白的表达,减少心肌Bax蛋白的表达, 提高Bcl-2/Bax 的比值和降低心肌细胞凋亡指数,与缺血再灌注组比较,差异有统计学意义（P＜0.01）。阿魏酸川芎嗪各项指标优于川芎嗪（P＜0.05或P＜0.01）。结论：阿魏酸川芎嗪能减轻大鼠心肌缺血再灌注损伤;其抗缺血再灌注诱导的心肌细胞凋亡的机制可能与其上调Bcl-2蛋白和下调Bax蛋白表达有关。     

腺苷A2b受体激活减轻小鼠肾缺血再灌注致肺损伤

目的研究腺苷A2b受体激活对肾缺血再灌注(RIR)致肺损伤的保护作用及其机制。方法雄性C57BL/6J小鼠随机分为:对照组(C组),缺血再灌注组(I/R组),缺血再灌注+A2bR激动剂Bay606583组(I/R+Bay组,1 mg/kg Bay术前15 min腹腔注射),缺血再灌注+A2bR激动剂Bay606583+Akt抑制剂LY294002组(I/R+Bay+LY组,1 mg/kg Bay+7.5 mg/kg LY术前15 min腹腔注射)及缺血再灌注+A2bR抑制剂MRS1754组(I/R+MRS组,1 mg/kg MRS术前15 min腹腔注射)。分别取血检测肾功能(血肌酐、血尿素氮);检测肺组织A2bR mRNA表达; Western blot检测肺组织p-Akt和A2bR的蛋白表达;检测各组小鼠肺组织湿重/干重比值(W/D)以及支气管肺泡灌洗液(BALF)中蛋白、TNF-α和IL-6的浓度;观察肺组织病理变化;采取动脉血进行动脉血气分析。结果肾缺血再灌注后血肌酐、血尿素氮升高,A2bR mRNA的表达随时间降低(P0.05),且p-Akt和A2bR的蛋白表达水平显著降低(P0.05)。另外,与对照组相比,再灌注后小鼠肺组织湿重/干重比值(W/D)、肺泡灌洗液蛋白、TNF-α和IL-6浓度明显增加(P0.05),肺病理损伤评分和氧合水平明显变差(P0.05),1 mg/kg Bay606583明显减轻上述损伤并增加p-Akt的表达,然而这一作用在应用Akt抑制剂LY294002后消失。结论腺苷A2b受体激活可能通过PI3K/Akt通路减轻肾缺血再灌注后肺组织损伤并改善氧合状态。     

三七总皂甙降低兔肺缺血再灌注损伤和抑制细胞凋亡

 目的: 探讨细胞凋亡与肺缺血再灌注损伤的关系以及三七总皂甙的作用及机制。方法: 健康日本大耳白兔84只,随机分为对照组、肺缺血再灌注1、3、5h组和相应三七总皂甙干预组。复制肺缺血再灌注损伤模型。用原位缺口末端标记(TUNEL)法、聚丙烯酰胺凝胶电泳观测肺组织细胞凋亡,原位杂交技术检测肺组织细胞Fas/FasL系统和Caspase-3基因表达。结果: 肺缺血再灌注组肺组织细胞凋亡指数(肺缺血再灌注5h组:22.08±1.93;对照组:2.04±0.67)、Fas/FasL和Caspase-3基因表达(肺缺血再灌注5h组:0.241±0.029;对照组:0.121±0.015)均显著高于对照组(P<0.01),并出现电泳梯形条带结构;三七总皂甙干预组Fas/FasL mRNA及其Caspase-3的表达(三七总皂甙干预5h组:0.199±0.020;肺缺血再灌注5h组:0.241±0.029)显著低于缺血再灌注组(P<0.01),肺组织细胞凋亡指数(三七总皂甙干预5h组:12.58±1.82;肺缺血再灌注5h组:22.08±1.93)也显著低于缺血再灌注组(P<0.01),梯形条带结构基本消失。肺组织细胞凋亡指数分别与Caspase-3 mRNA及Fas/FasL mRNA之间均呈显著正相关(P<0.01)。结论:三七总皂甙可能通过抑制Fas/FasL系统的激活,阻遏肺组织细胞凋亡,从而减轻肺缺血再灌注损伤。     

比较热休克蛋白A5和3-甲基腺嘌呤和介导小鼠脑缺血再灌注损伤的保护作用

目的:比较研究热休克蛋白A5(HSPA5)和3-甲基腺嘌呤(3-MA)介导小鼠脑缺血再灌注(I/R)损伤性自噬的保护作用。方法:成年雄性BALB/c小鼠30只,分为6组:sham组、缺血再灌注组(I/R组)、vehicle+I/R组、3-甲基腺嘌呤(3-MA)+I/R组、scramble siRNA+I/R组和HSPA5 siRNA+I/R组,每组5只。采用大脑中动脉阻塞(MCAO)60 min后再灌注24 h制作小鼠I/R模型。Vehicle+I/R组和3-MA+I/R将5μl 0.9%Na Cl或3-MA(30 mg/ml)在MCAO前30 min侧脑室注射;scramble siRNA+I/R group组和HSPA5 siRNA+I/R组将5μl scramble siRNA或HSPA5 siRNA(2μg/μl)在MCAO前24 h侧脑室注射。通过小鼠I/R后神经功能评分确定运动功能障碍程度。小鼠神经细胞内自噬体形成用透射电子显微镜测定,再灌注24 h缺血大脑皮层(LC3)-II/LC3-I表达用Western Blot方法检测。小鼠I/R后缺血大脑神经细胞损伤用Nissl染色进行观察。结果:HSPA5和3-MA可以影响I/R小鼠行为学改变并使脑缺血性损伤和神经症状加重(P0.05)。透射电子显微镜检测可见,sham组小鼠大脑皮层神经细胞形态正常,I/R组小鼠缺血大脑皮层神经元胞质中细胞器减少,形成自噬体。与sham组小鼠比较,I/R组小鼠缺血大脑皮层LC3-II蛋白表达水平显著增高(P0.05);3-MA+I/R或HSPA5 siRNA+I/R小鼠缺血大脑皮层LC3-II蛋白表达水平明显低于I/R小鼠(P0.05)。结论:HSPA5和3-MA在介导小鼠脑缺血再灌注损伤导致的自噬可发挥相同的保护作用,并且促进神经细胞凋亡。     

虎杖甙下调兔肺缺血再灌注损伤时TLR4的表达

目的： 研究家兔肺缺血再灌注损伤时Toll样受体4(TLR4)信号转导通路变化及虎杖甙(PD)对其影响。方法：复制在体肺缺血再灌注损伤模型。健康日本大耳白免30只, 随机分为对照(C)组、缺血再灌注(IR)组、PD组。鲎试剂试管法检测血浆内毒素(ET); 免疫组化法检测肺组织TLR4、核因子-κB p65(NF-κB p65)和热休克蛋白70(HSP70)的蛋白表达；原位杂交法检测肺组织细胞间黏附分子-1(ICAM-1)mRNA表达；电镜观察肺超微结构变化。结果：IR组、PD组与C组相比血浆ET无显著差异(均P>0.05)。IR组肺组织TLR4、NF-κB p65、HSP70蛋白及ICAM-1mRNA表达较C组显著升高(均P<0.01)；PD组上述改变较IR组明显下降，但仍高于C组(均P<0.01); 电镜见PD组肺超微结构损伤明显轻于IR组。结论：肺缺血再灌注损伤过程中HSP70合成增加，作为内源性配体之一上调TLR4，可能通过激活NF-κB，进而诱导ICAM-1的转录和分泌。PD可以下调该信号转导途径，减轻肺缺血再灌注损伤。     

黄芪甲苷通过toll样受体4/核因子κB通路介导辐射所致肾损伤的防护作用

目的 探讨黄芪甲苷(AS-Ⅳ)是否通过toll样受体4(TLR4)/核因子κB(NF-KB)介导的信号通路对辐射诱导肾脏损伤起到保护作用.方法 将小鼠分为正常对照组、DMSO溶剂组、辐射组(IR)、IR+AS-Ⅳ20 mg/kg组和IR+AS-Ⅳ 40 mg/kg组.小鼠给予AS-Ⅳ腹腔注射1个月后,以8Gy的60Co...     

PPARβ／δ激动剂减轻小鼠心肌缺血／再灌注损伤

目的：研究PPARβ/δ激动剂GW0742对小鼠心肌缺血/再灌注（ischemia-reperfusion,I/R）损伤的影响。方法：将小鼠分成4组,分别为溶剂假手术组[二甲基亚砜（DMSO）,sham组],激动剂假手术组（GW0742 sham组）,溶剂手术组（DMSO I/R组）和激动剂手术组（GW0742 I/R组）。术后于小鼠腹腔注射DMSO及GW0742。采用ELISA法检测各组血浆中的乳酸脱氢酶（lactate dehydrogenase,LDH）,免疫印迹法检测各组核因子-κB（NF-κB）p65亚单位及细胞间黏附分子-1（ICAM-1）蛋白的表达量。结果：GW0742 I/R组血浆中的LDH较DMSO I/R组减低（P〈0.001）。GW0742 I/R组心肌中的NF-κBp65和ICAM-1蛋白表达量较DMSO I/R组减低（分别为P〈0.001和P〈0.05）。结论：GW0742可以减轻小鼠心肌I/R损伤。PPARβ/δ是机体抗心肌I/R损伤的重要防御因子之一。     

云芝糖肽对人PBMC中TLR5信号通路调控机制的研究

目的:研究云芝糖肽(PSP)对人外周血单个核细胞(PBMC)中TLR5信号通路的调控作用,探索PSP对Toll样通路的免疫调节机制。方法:体外分离、培养人PBMC,分为对照组和PSP处理组,采用实时荧光定量PCR(Q-PCR)技术对PSP处理人PBMC前后,PBMC中的TLR5信号通路中相关基因的表达差异情况进行定量分析。结果:PSP处理的实验组与对照组相比较,TLR5信号通路中的TLR5、IRAK4、TRAF6、IRF5和NF-κB基因的表达水平均显著增高(P<0.05),但AP-1基因的表达降低(P<0.05)。结论:PSP对PBMC中TLR通路的调控可能主要通过NF-κB和IRF5调控终端效应因子来发挥免疫调节作用,这些为进一步探讨PSP的免疫调节作用机理提供了实验依据。     

Resveratrol, a polyphenol phytoalexin, protects cardiomyocytes against anoxia/reoxygenation injury via the TLR4/NF-κB signaling pathway

Previous studies indicate resveratrol pretreatment can protect cardiomyocytes. However, it is largely unknown whether resveratrol protects cardiomyocytes when applied at reperfusion. The purpose of this study was to investigate whether resveratrol given at reoxygenation could protect cardiomyocytes under the anoxia/reoxygenation (A/R) condition and to examine the underlying mechanism. In this study, primary cultures of neonatal rat cardiomyocytes were randomly distributed into three groups: control group, A/R group (cultured cardiomyocytes were subjected to 3 h anoxia followed by 2 h reoxygenation), and the resveratrol group (cardiomyocytes were subjected to 3 h anoxia/2 h reoxygenation, and 5, 10 or 20 μM resveratrol was applied 5 min after reoxygenation). In order to evaluate cardiomyocyte damage, cell viability, lactate dehydrogenase (LDH) release, caspase-3 activity, and apoptosis were analyzed by the cell counting kit (CCK)-8 assay, colorimetric method and flow cytometry, respectively. The mRNA and protein expression of Toll-like receptor 4 (TLR4) were detected by quantitative real-time PCR and western blot analysis. Nuclear factor-κB (NF-κB) p65 protein and I-κBα protein levels were also examined by western blot analysis. The levels of proin?ammatory cytokines in the culture medium were assessed by enzyme-linked immunosorbent assay. We found that resveratrol prevented a reduction in cell viability, decreased the amount of LDH release, attenuated apoptotic cells and decreased caspase-3 activity induced by A/R in cardiomyocytes. Furthermore, resveratrol treatment significantly attenuated the TLR4 expression, inhibited NF-κB activation and reduced the levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1β caused by A/R injury in the culture medium. Treatment with resveratrol shortly after the onset of reoxygenation improves cell survival and attenuates A/R-induced inflammatory response. This protection mechanism is possibly related to the TLR4/NF-κB signaling pathway.     

促红细胞生成素抑制大鼠体外循环术致急性肾损伤时NF-κB P65和ICAM-1表达

 目的 研究大鼠体外循环（CPB）术致急性肾损伤时肾脏核转录因子-κB（ NF-κB ）P65和内皮细胞表面黏附分子-1（ICAM-1）表达水平变化及促红细胞生成素(EPO)对其的抑制作用。方法 30只雄性SD大鼠随机分为3组（每组n=10）:Sham组、CPB组和EPO组, Sham组建立CPB模型,不行体外转流,其余2组行体外转流,EPO组于转流前在预充液中加入3 000U/kg的EPO。分别于肝素化后转流前 (T0)和转流结束后(T1)、术后0.5 (T2)、1 (T3)、2 ( T4)和24 h (T5)检测血清肌酐水平, 术后24h取肾脏组织,HE染色观察组织形态,并分别采用免疫组化和western-blot法检测肾组织中NF-κB P65和ICAM-1表达。结果 术后CPB组各时间点与sham组比较血清肌酐水平均明显升高（P<0.05）,与CPB组相比,EPO组的肌酐水平明显下降（P<0.05）;CPB组肾组织中NF-κB p65及ICAM-1表达水平均明显高于sham组（P<0.05）,EPO组NF-κB p65及ICAM-1表达水平均低于CPB组（P<0.05）;病理学检查显示EPO组的肾小管上皮细胞肿胀、胞质内空泡形成、间质出血明显减轻。结论EPO可抑制大鼠体外循环后肾脏NF-κB P65及ICAM-1表达,从而减轻大鼠体外循环引起的肾脏损伤。     

罗格列酮对阿霉素肾病大鼠肾组织中PPARγ、TGF-β1表达的影响

目的：探讨阿霉素肾病大鼠肾组织中过氧化物酶体增殖物激活受体（PPARγ）、转化生长因子β₁（TGF-β₁）表达和罗格列酮对阿霉素肾病大鼠的肾脏保护作用及其可能机制。方法: 将大鼠随机分成3组，正常对照组（n=6）、阿霉素肾病组（n=7）、罗格列酮治疗组（n=7），12周后测大鼠尿蛋白、血浆白蛋白、血脂和血肌酐、尿素氮，用免疫组化检测肾组织NF-κB p65的核转位及ELISA（夹心法）检测肾组织NF-κB p65的活性，RT-PCR测肾皮质PPARγ mRNA及TGF-β₁ mRNA的表达及免疫印迹检测肾皮质PPARγ、TGF-β₁蛋白表达，并进行相关分析。 结果: 与阿霉素肾病组相比，罗格列酮治疗组大鼠24 h尿蛋白排泄减少，血清白蛋白升高，血甘油三酯和胆固醇下降,差异显著(P＜0.01),肾脏病理损害减轻；肾组织NF-κB p65活化和TGF-β₁ mRNA和蛋白的表达均明显受抑制，而肾皮质PPARγ mRNA和蛋白表达显著增强，差异显著（P＜0.01)；阿霉素肾病组和罗格列酮治疗组大鼠肾组织中NF-κBp65活性与PPARγ mRNA表达呈直线负相关（r=－0.8305, P＜0.01）；肾组织中PPARγ mRNA与TGF-β₁ mRNA表达呈直线负相关（r=－0.7938, P＜0.01 ）。结论:罗格列酮作用于阿霉素肾病大鼠后，可能通过上调PPARγ表达，部分抑制肾组织NF-κB p65活性，进而抑制肾组织中TGF-β₁ 表达，从而使系膜基质沉积减少，肾组织病变减轻。     

Chlorogenic Acid Attenuates Lipopolysaccharide-Induced Acute Kidney Injury by Inhibiting TLR4/NF-κB Signal Pathway

Chlorogenic acid (CGA), a polyphenolic compound, exists widely in medicinal herbs, which has been shown a strong antioxidant and anti-inflammatory effect. This study investigated the protective effects and mechanism of CGA on lipopolysaccharide (LPS)-induced acute kidney injury (AKI). Treatment of CGA successfully ameliorates LPS-induced renal function and pathological damage. Moreover, CGA dose-dependently suppressed LPS-induced blood urea nitrogen (BUN), creatinine levels, and inflammatory cytokines TNF-α, IL-6, and IL-1β in serum and tissue. The relative proteins’ expression of TLR4/NF-κB signal pathway was assessed by western blot analysis. Our results showed that CGA dose-dependently attenuated LPS-induced kidney histopathologic changes, serum BUN, and creatinine levels. CGA also suppressed LPS-induced TNF-α, IL-6, and IL-1β production both in serum and kidney tissues. Furthermore, our results showed that CGA significantly inhibited the LPS-induced expression of phosphorylated NF-κB p65 and IκB as well as the expression of TLR4 signal. In conclusion, our results provide a mechanistic explanation for the anti-inflammatory effects of CGA in LPS-induced AKI mice through inhibiting TLR4/NF-κB signaling pathway.     

Immunomodulatory role of recombinant human erythropoietin in acute kidney injury induced by crush syndrome via inhibition of the TLR4/NF-κB signaling pathway in macrophages

Abstract

Objective: The present study aimed to investigate whether recombinant human erythropoietin (rHuEPO) plays an immunomodulatory function by regulating the TLR4/NF-κB signaling pathway.

Materials and methods: C57BL/6 mice were intraperitoneally injected with rHuEPO and, half an hour later, with 50% glycerol at the dose of 7.5?ml/kg to induce crush syndrome (CS)-acute kidney injury (AKI). The levels of TNF-α, IL-1β, IL-6, serum creatinine (Scr), and creatine kinase (CK) were measured. The kidney tissues were analyzed by HE staining, and macrophage infiltration was detected by immunohistochemistry. Double immunofluorescence staining, RT-qPCR, and western blotting were conducted to analyze TLR4/NF-κB p65 expression. Ferrous myoglobin was co-cultured with RAW264.7 cells to mimic crush injury and the production of proinflammatory cytokines. The expression levels of TLR4 and NF-κB p65 were measured.

Results: In vivo study results revealed that rHuEPO ameliorated renal function, tissue damage, production of proinflammatory cytokines, and macrophage infiltration in the kidneys. The protein and mRNA expression levels of genes involved in the TLR4/NF-κB signaling pathway in CS-induced AKI mice were upregulated (p?<?.05). Meanwhile, the expression levels of TLR4, NF-κB p65, and proinflammatory cytokines in RAW264.7 cells were downregulated in CS-AKI mice injected with rHuEPO (p?<?.05).

Conclusions: Our results demonstrated the immunomodulatory capacity of rHuEPO and confirmed that rHuEPO exerts protective effects against CS-induced AKI by regulating the TLR4/NF-κB signaling pathway in macrophages. Therefore, our findings highlight the therapeutic potential of rHuEPO in improving the prognosis of CS-AKI patients.     

脂多糖通过NF-κB途径上调大鼠腹膜间皮细胞表达CD40和ICAM-1

目的 观察脂多糖(LPS)作用下大鼠腹膜间皮细胞NF-κB活性及其对CD40和细胞间黏附分子1(ICAM-1)表达的影响.方法 分离及培养大鼠腹膜间皮细胞.LPS不同浓度作用12 h 及LPS (5 μg/ml)作用不同时间点收集细胞;LPS(5 μg/ml)或BAY11-7085(一种IκBα的磷酸化抑制剂)不同浓度(1 μmol/L和5 μmol/L)预处理3 h加LPS,作用3 h后收集细胞;采用RT-PCR方法检测CD40和ICAM-1 mRNA表达.采用蛋白印迹检测NF-κB和磷酸化NF-κB(p-NF-κB)蛋白表达.结果 与常规培养基对照组相比,5 μg/ml LPS组CD40和ICAM-1 mRNA表达显著升高(P<0.05),10 μg/ml LPS组显著高于5 μg/ml LPS作用组(P<0.05).5 μg/ml LPS 作用下,ICAM-1 mRNA表达从1 h开始升高,3 h达到高峰,之后逐渐降低.CD40 mRNA表达在1 h无显著变化,3 h时迅速达到高峰,之后逐渐降低.常规培养的大鼠腹膜间皮细胞结构性表达p-NF-κB蛋白;加入LPS后,p-NF-κB蛋白表达显著增加,其中30 min～1 h表达最强,之后逐渐降低,至2 h仍显著高于常规培养组(P<0.05).加入5 μmol/L BAY11-7085后,LPS诱导的CD40和ICAM-1 mRNA表达显著降低(P<0.05),与正常对照组相比差异无统计学意义. 结论 LPS以时间依赖和浓度依赖模式上调CD40和ICAM-1的表达.NF-κB信号途径参与调节LPS诱导的大鼠腹膜间皮细胞CD40和ICAM-1的表达.