ROS-NF-κB-p38MAPK通路探索榄香烯联合硼替佐米抗多发性骨髓瘤的机制研究

目的:基于ROS-NF-κB-p38MAPK信号通路探讨榄香烯(ELE)联合硼替佐米(BTZ)抗多发性骨髓瘤的作用机制。方法:CCK-8法检测细胞活性。SPF级裸鼠构建人源性骨髓瘤移植瘤模型,设立对照组(NC组)、BTZ组、ELE组及联合处理组。Tunel染色观察肿瘤组织凋亡,Western Blot检测Caspase-3、Bcl-2、NF-κB及p38 MAPK表达,流式细胞术检测人源性骨髓瘤U266细胞周期、凋亡及活性氧(ROS)表达。结果:当4.0μmol/L ELE联合50 nmol/L BTZ处理U266时,细胞活性均显著低于其他组。BTZ组、ELE组及联合组裸鼠肿瘤体积明显小于NC组(P<0.05),联合组体积最小;Tunel染色显示NC组凋亡水平低于BTZ组、ELE组及联合组(P<0.05),联合组最低;Western Blot结果显示BTZ组、ELE组及联合组Caspase-3及p38 MAPK表达显著高于NC组,Bcl-2及NF-κB表达显著低于NC组。BTZ组、ELE组及联合组细胞凋亡水平及细胞内ROS表达显著高于NC组(P<0.05)。结论:ELE可能通过调控ROS/NF-κB/p38 MAPK信号通路增强BTZ促骨髓瘤细胞凋亡,从而实现其抗肿瘤作用。

水飞蓟素通过共同抑制TLR4/NF-κB和TNF-α/ROS/P38MAPK通路减轻糖尿病肾病大鼠肾脏损伤的研究

目的:探讨水飞蓟素通过共同抑制Toll样受体4/核因子-κB(TLR4/NF-κB)和肿瘤坏死因子α/活性氧簇/P38丝裂原活化蛋白激酶(TNF-α/ROS/P38MAPK)通路减轻糖尿病肾病(DN)大鼠肾脏损伤的机制。方法:选取健康SD大鼠50只,按随机数字表法分为对照组、模型组、低剂量水飞蓟素组、中剂量水飞蓟素组、高剂量水飞蓟素组,每组10只。建模成功并治疗8周后,生化分析仪测定各组大鼠空腹血糖(FBG)、血肌酐(Scr)、尿素氮(BUN)、胱抑素C(Cys-C)、β_(2)微球蛋白(β_(2)-MG)、24 h尿蛋白(UTP)水平;计算肾脏指数;试剂盒检测各组大鼠肾组织丙二醛(MDA)、总抗氧化能力(T-AOC)水平;RT-PCR检测各组大鼠TLR4,NF-κB,TNF-α和P38MAPK等mRNA的表达水平。结果:与对照组相比,模型组体质量、T-AOC均降低(P<0.05),肾脏指数和FBG,Scr,BUN,Hcy,Cys-C,β_(2)-MG,24 h UTP,MDA,TLR4 mRNA,NF-κB p65 mRNA,TNF-αmRNA,P38MAPK mRNA均升高(P<0.05)。低、中、高剂量水飞蓟素组体质量、T-AOC水平均低于对照组,且均高于模型组(P<0.05);低、中、高剂量水飞蓟素组肾脏指数和FBG,Hcy,Cys-C,β_(2)-MG,24 h UTP,MDA,TLR4 mRNA,NF-κB p65 mRNA,TNF-αmRNA,P38MAPK mRNA均高于对照组,且均低于模型组(P<0.05);低、中剂量水飞蓟素组Scr,BUN水平均高于对照组,且低于模型组(P<0.05);高剂量水飞蓟素组Scr,BUN水平均低于模型组(P<0.05),高于对照组,但差异无统计学意义(P>0.05)。结论:水飞蓟素可调控TLR4/NF-κB和TNF-α/ROS/P38MAPK通路,可通过抑制其激活减轻氧化应激、减轻DN大鼠的肾脏损伤。

α1-antitrypsin combined with bone marrow mesenchymal stem cells regulates retinopathy in diabetic rats via p38 MAPK/NF-κB signaling pathway

Objective:To investigate the effect ofα1-antitrypsin combined with bone marrow mesenchymal stem cells on retinopathy in diabetic rats and its mechanism.Methods:A model of diabetic retinopathy was established by intraperitoneal injection of streptozotocin.The 30 Wistar rats successfully modeled were randomly divided into a model group,a bone marrow mesenchymal stem cell group and a combined group(α1-antitrypsin combined with bone marrow Mesenchymal stem cells),the blood glucose and serum insulin levels of diabetic rats were measured 4 weeks after treatment.Enzyme-linked immunosorbent assay(ELISA)for measuring serum inflammatory factors IL-1β,IL-6 and TNF-α in rats.Observing the pathological morphology of rat retina under hematoxylin-eosin staining(HE).TUNEL staining to observe the apoptosis of rat retinal nerve cells.Immunohistochemical method to detect the expression level of CD45 in retinal tissue.Real-time fluorescence quantitative PCR was used to detect the expression of retinal vascular endothelial growth factor(VEGF),hypoxiainducible factor-1α(HIF-1α),and angiotensinⅡ(ANGⅡ)mRNA.Western blot was used to detect the expression of p38 MAPK/NF-κB signaling pathway-related proteins in the retinal tissue of each group of rats.Results:Compared with the control group,the rats in the model group had increased blood glucose,decreased insulin levels,increased serum IL-1β,IL-6,and TNF-α levels,and had obvious lesions in the retina.CD45 showed high expression in retinal tissue,VEGF,HIF-1α,ANGⅡ mRNA expression increased,p-p38,p-p65,p-IκBα protein expression increased(P<0.05).Compared with the model group,the bone marrow mesenchymal stem cell group and the combined group have decreased blood glucose,increased insulin levels,and decreased serum IL-1β,IL-6 and TNF-α levels.Retinopathy is improved,apoptosis of retinal nerve cells is reduced,CD45 expression in retinal tissue is reduced,VEGF,HIF-1α,ANGⅡ mRNA expression is decreased,and p-p38,p-p65,p-IκBα protein expression is decreased.Compared with the bone marrow mesenchymal stem cell group,the effect of the combined group was more obvious(P<0.05).Conclusion:α1-antitrypsin combined with bone marrow mesenchymal stem cell transplantation can improve the degree of retinopathy in diabetic rats.The mechanism may be related to the inhibition of p38 MAPK/NF-κB signaling pathway.

The functional analysis of transiently upregulated miR-101 suggests a “braking” regulatory mechanism during myogenesis

Skeletal muscle differentiation is a highly coordinated process that involves many cellular signaling pathways and microRNAs(miRNAs).A group of muscle-specific miRNAs has been reported to promote myogenesis by suppressing key signaling pathways for cell growth.However,the functional role and regulatory mechanism of most non-muscle-specific miRNAs with stage-specific changes during differentiation are largely unclear.Here,we describe the functional characterization of miR-101a/b,a pair of non-muscle-specific miRNAs that show the largest change among a group of transiently upregulated miRNAs during myogenesis in C2C12 cells.The overexpression of miR-101a/b inhibits myoblast differentiation by suppressing the p38/MAPK,Interferon Gamma,and Wnt pathways and enhancing the C/EBP pathway.Mef2a,a key protein in the p38/MAPK pathway,was identified as a direct target of miR-101a/b.Interestingly,we found that the long non-coding RNA(lncRNA)Malat1,which promotes muscle differentiation,interacts with miR-101a/b,and this interaction competes with Mef2a mRNA to relieve the inhibition of the p38/MAPK pathway during myogenesis.These results uncovered a“braking”role in differentiation of transiently upregulated miRNAs and provided new insights into the competing endogenous RNA(ceRNA)regulatory mechanism in myoblast differentiation and myogenesis.

X线照射增加肺癌细胞A549产生IL-8的研究

目的观察照射对肺癌细胞A549产生IL-8的影响及探索其可能机制。方法采用不同剂量X线照射A549细胞,于照射后不同时间收集细胞上清,细胞RNA以及蛋白质,采用RT-PCR检测照射后A549细胞IL-8 mRNA表达水平,并进一步行实时定量PCR验证照射后A549细胞IL-8 mRNA表达水平,行ELISA检测照射后上清中IL-8表达水平,Western Blot检测照射后A549细胞信号通路分子表达情况,采用p38 MAPK抑制剂、NF-κB抑制剂及ROS清除剂预处理细胞,ELISA验证抑制剂对照射诱导A549细胞产生IL-8表达水平的影响。结果照射增加A549细胞的IL-8的表达水平,并具有剂量、时间效应。照射激活A549细胞中p38 MAPK和NF-κB信号通路分子。抑制p38 MAPK和抑制NF-κB能够阻断照射诱导A549细胞产生的IL-8。抑制ROS后并不能抑制照射诱导A549细胞产生的IL-8。结论X线照射能增加A549细胞IL-8的产生,可能与通过激活p38 MAPK和NF-κB信号通路相关,并呈ROS非依赖性模式。