核因子抑制剂对心肺转流中心肌细胞ICAM-1表达的影响

目的探讨核因子抑制剂吡咯二硫氨基甲酸酯(PDTC)对心肺转流(CPB)中心肌细胞核因子-κB(NF-κB)p65和细胞间粘附分子-1(ICAM-1)活化的影响。方法12只犬随机分为PDTC组(P组)和对照组(C组),每组6只。P组于CPB转机前静脉注入PDTC 30 mg/kg,C组静脉注入等容量生理盐水。两组均全心缺血60 min,恢复灌注60 min。于CPB 5 min、阻断60 min及开放60 min时,用自制电钻取心肌组织,一部分置于30%甲醛溶液固定,制成石蜡切片,采用SABC法免疫组化染色,观察NF-κB p65及ICAM-1蛋白的表达情况,另一部分置于液氮中保存,用于测定组织中髓过氧化物酶(MPO)的含量。结果在CPB过程中,随着时间的延长NF-κB p65及ICAM-1蛋白表达逐渐增强,MPO的含量逐渐增多,而PDTC能减少其表达和组织中MPO的含量,组间比较差异有显著意义(P<0.05,P<0.01)。结论PDTC能抑制CPB过程中NF-κB p65及ICAM-1蛋白的表达,减少炎性细胞浸润。     

Differential regulation of cytokine genes in gingival epithelial cells challenged by Fusobacterium nucleatum and Porphyromonas gingivalis

IL-8 mRNA in human gingival epithelial cells (HGECs) is up-regulated by Fusobacterium nucleatum, and up-/down-regulated by Porphyromonas gingivalis in a complex interaction in the early stages (< or = 4 h) after infection. The mechanisms involved in this regulation in response to F. nucleatum and/or P. gingivalis infection, and identification of co-regulated cytokine genes, are the focus of this investigation. Heat, formalin or protease treatment of F. nucleatum cells attenuated the IL-8 mRNA up-regulation. NF-kappaB, mitogen-activated protein kinase (MAPK) p38 and MAPK kinase/extracellular signal-regulated kinase (MEK/ERK) pathways were involved in IL-8 mRNA induction by F. nucleatum. Pretreatment of P. gingivalis with heat, formalin or protease enhanced IL-8 mRNA induction. NF-kappaB, MARK p38, and MEK/ERK pathways were also involved in this induction. In contrast, down-regulation of IL-8 mRNA by P. gingivalis involved MEK/ERK, but not NF-kappaB or MAPK p38 pathways. cDNA arrays analysis revealed that mRNA down-regulation by P. gingivalis is a specific reaction that only a number of genes, e.g. IL-1beta, IL-8, macrophage inflammatory protein-2alpha, and migration inhibitory factor-related protein-14, are affected based on examination of 278 cytokine/receptor genes. These data indicate that F. nucleatum and P. gingivalis trigger specific and differential gene regulation pathways in HGECs.     

~(60)Co γ射线照射后血管内皮细胞CD54表达变化及PDTC的干预作用

 目的　研究血管内皮细胞在受60 Coγ射线照射后粘附分子CD5 4的表达与单核样细胞在血管内皮细胞上粘附变化的关系 ,观测抗氧化剂PDTC预处理对CD5 4表达及白细胞粘附的影响。方法　培养的ECV30 4细胞接受 16Gy60 Coγ放射线照射后不同时点 ,检测视黄酸诱导的单核样HL 6 0细胞在内皮细胞上的粘附数量 ,内皮细胞CD5 4mRNA及蛋白表达 ,核转录因子κBDNA结合活性以及抗氧化剂PDTC预处理对上述指标的影响。结果　照射后 8h ,HL 6 0细胞粘附数较对照显著上升 ,2 4h时较对照增加 77%。受照后 2h ,CD5 4mRNA水平较对照增加 36 % ,2 4h增加 182 %。照射后 4～ 32h ,CD5 4蛋白表达较对照增加 6 6 %～ 2 6 8%。NF κB DNA结合活性在照射后 2h达峰值 ,较对照增高 97%。PDTC预作用后 2h ,NF κB DNA结合活性较未处理组下降了 4 4 % ,作用后 4h ,CD5 4mRNA表达量下降 35 % ,同时HL 6 0细胞粘附数减少 2 6 %。结论　CD5 4表达上调是60 Coγ射线照射引起单核细胞在内皮细胞上...     

特异性NF-κB抑制剂对单侧输尿管梗阻大鼠肾间质纤维化的治疗作用

目的探讨特异性NF-κB抑制剂对单侧输尿管梗阻大鼠肾间质纤维化的治疗作用及其可能机制。方法应用特异性NF-κB抑制剂PDTC治疗单侧输尿管梗阻大鼠模型,常规HE、PASM染色观察肾间质病理变化,电泳迁移率变动分析法检测肾组织中NF-κB的活性,免疫组化法检测TGF-β1、MCP-1的表达,并采用图像分析系统进行半定量分析。结果治疗组较模型组大鼠梗阻侧肾脏病理变化明显减轻,肾皮质NF-κB活性及小管间质TGF-β1、MCP-1表达明显降低(P<0·01)。结论特异性NF-κB抑制剂通过抑制NF-κB激活并进一步减少下游炎症和致纤维化细胞因子的表达以达到治疗肾间质纤维化的作用。     

NF-κB抑制剂二硫代氨基甲酸吡咯烷提高卵巢癌细胞顺铂化疗的敏感性

目的:探讨核因子κB(nuclear factor kappa B, NF-κB)抑制剂二硫代氨基甲酸吡咯烷(pyrrolidine dithiocarbamate,PDTC)提高人卵巢癌SKOV-3细胞对顺铂(cisplatin)化疗敏感性的作用及其可能的机制.方法:用不同浓度PDTC联合顺铂在不同时间作用于卵巢癌SKOV-3细胞,MTT法观察药物作用对细胞生长的抑制,Western Blotting分析胞质内NF-κB 抑制蛋白α(inhibitor of NF-κB ,I-κBα)、胞核P65蛋白的表达;流式细胞术检测细胞凋亡.结果:PDTC(10～40 μmol/L)或顺铂(0.1～100 μg/ml )均明显抑制SKOV-3细胞的生长(P<0.05或P<0.01),并引起细胞的凋亡;小剂量PDTC(2.5、5 μmol/L)和顺铂(0.01 μg/ml)联合应用与单用顺铂比较,可明显增加细胞生长抑制率和细胞凋亡率(均P<0.05).单用顺铂组与对照组比较,胞质I-κBα蛋白减少而胞核P65蛋白增多,联合使用PDTC可逆转此现象.结论:小剂量PDTC可增强卵巢癌细胞对顺铂的敏感性,这一作用可能与PDTC增加I-κBα蛋白的表达而抑制P65蛋白进入核内有关.     

NF-κB抑制剂对PMMA颗粒诱导的小鼠颅骨骨溶解抑制作用的实验研究

目的研究NF-kappa B抑制剂PDTC及NAC对PMMA骨水泥颗粒诱导的小鼠颅骨骨溶解的抑制作用。方法8周龄BABL/C小鼠,颅骨表面均匀散布PMMA颗粒,诱导骨溶解模型,分4组给予不同处理因素,分别为PBS、PDTC、NAC及生理盐水组。颅骨未加颗粒的小鼠和加颗粒后仅给予生理盐水的小鼠分别作为阴性对照和阳性对照。2周后取出颅骨,石蜡包埋、切片后行HE染色、TRAP染色、NF-κB P65免疫组化染色。结果在PMMA颗粒诱导下小鼠颅骨有明显骨溶解作用,PDTC及NAC均有明显的抑制骨溶解作用,在相同剂量情况下,PDTC比NAC的骨溶解抑制作用更强。结论NF-kappa B抑制剂PDTC及NAC对PMMA骨水泥颗粒诱导的小鼠颅骨骨溶解有明显的抑制作用。     

PDTC抑制大鼠骨关节炎一氧化氮表达的实验研究

目的：观察核因子kappa B（NF-kappa B）抑制剂吡咯烷二硫代氨基甲酸盐（PDTC）对大鼠骨关节炎一氧化氮表达的影响，探讨NF-kappaB抑制剂能否应用于骨关节炎的治疗。方法：通过前交叉韧带切断的方法制造大鼠骨关节炎（OA）动物模型，将大鼠动物模型分为实验组和对照组，于造模后每隔48h肌肉注射PDTC10mg／kg，对照组仅肌注生理盐水0．1ml，术后6周后处死大鼠，观察实验组和对照组一氧化氮的免疫组化染色，比较两组问有无差异。结果：实验组和对照组一氧化氮免疫组化染色阳性细胞分数分别为51．8±10．0和70．2±12．4，二者间差异有统计学意义。结论：NF-kappaB抑制剂能够抑制大鼠骨关节炎一氧化氮的表达，有潜在治疗骨关节炎的意义。     

Endoplasmic reticulum (ER) stress: hepatitis C virus induces an ER-nucleus signal transduction pathway and activates NF-kappaB and STAT-3

Human hepatitis C virus (HCV) is the leading cause of chronic hepatitis, which often results in liver cirrhosis and hepatocellular carcinoma. The HCV RNA genome codes for at least ten proteins. The HCV non-structural protein 5A (NS5A) has generated considerable interest due to its effect on interferon sensitivity via binding and inactivating the cellular protein kinase, PKR. It has been shown that NS5A engages in the endoplasmic reticulum (ER)-nucleus signal transduction pathway. The expression of NS5A in the ER induces an ER stress ultimately leading to the activation of STAT-3 and NF-kappaB. This pathway is sensitive to inhibitors of Ca(2+) uptake in the mitochondria (ruthenium red), Ca(2+) chelators (TMB-8, EGTA-AM), and antioxidants (PDTC, NAC, Mn-SOD). The inhibitory effect of protein tyrosine kinase (PTK) inhibitors indicates the involvement of PTK in NF-kappaB activation by NS5A. This implicates an alternate pathway of NF-kappaB activation by NS5A. The actions of NS5A have also been studied in the context of an HCV subgenomic replicon inducing a similar intracellular event. Thus, activation of NF-kappaB leads to the induction of cellular genes, which are largely antiapoptotic in function. These studies suggest a potential function of NS5A in inducing chronic liver disease and hepatocellular carcinoma associated with HCV infection.     

吡咯烷二硫氨基甲酸对人肺腺癌A549细胞的生长抑制作用

目的:探讨NF-κB抑制剂吡咯烷二硫氨基甲酸(PDTC)对人肺腺癌A549细胞的生长抑制作用及可能机制。方法:不同浓度PDTC(25μmol/L、50μmol/L、100μmol/L)干预A549细胞24h、48h、72h后,MTT法检测细胞生长抑制率,Westernblot和免疫细胞化学法分别检测PDTC干预48h后A549细胞凋亡抑制基因bcl-2和增殖细胞核抗原(PCNA)的表达情况。结果:随着PDTC干预浓度的增大和时间延长,A549细胞生长抑制率增加(P<0.05、0.01);PDTC干预后Bcl-2及PCNA蛋白表达均下降,呈剂量依赖性(r=-0.980,P<0.01;r=-0.977,P<0.01)。结论:PDTC可抑制人肺腺癌A549细胞生长,其机制可能与Bcl-2表达下调及抑制细胞增殖有关。