目的:研究胰岛素样生长因子(IGF-1)对核转录因子kappaB(nuclear factor of kappaB,NF-κB)p65活性的影响,探讨胰岛素样生长因子防治肌萎缩的作用及其机制。方法:Wistar大鼠48只,随机分为失神经对照组和实验组(药物组),取各组不同时段腓...目的:研究胰岛素样生长因子(IGF-1)对核转录因子kappaB(nuclear factor of kappaB,NF-κB)p65活性的影响,探讨胰岛素样生长因子防治肌萎缩的作用及其机制。方法:Wistar大鼠48只,随机分为失神经对照组和实验组(药物组),取各组不同时段腓肠肌(gastrocnemius,GAS)样本,测定肌肉萎缩程度并采用逆转录聚合酶链反应(RT-PCR)与Western Blot技术检测NF-κB mRNA和蛋白质的表达量。结果:去神经骨骼肌萎缩时,药物各组与失神经组的腓肠肌NF-κB的mRNA和蛋白质的表达在去神经支配后第2、7、14、28天同时段比较均下调,P<0.01。结论:大鼠失神经骨骼肌萎缩早期,胰岛素样生长因子是通过NF-κB途径来防治失神经早期的骨骼肌萎缩的。展开更多
目的利用NF-kappaBp50基因敲除小鼠建立子宫内膜异位症模型探索NF-kappaBp50亚单位在子宫内膜异位症发生发展中的作用。方法利用子宫内膜移植法建立P50基因敲除小鼠及野生型对照小鼠的子宫内膜异位症动物模型,检测建模后异位病灶大小、...目的利用NF-kappaBp50基因敲除小鼠建立子宫内膜异位症模型探索NF-kappaBp50亚单位在子宫内膜异位症发生发展中的作用。方法利用子宫内膜移植法建立P50基因敲除小鼠及野生型对照小鼠的子宫内膜异位症动物模型,检测建模后异位病灶大小、免疫组化检测异位病灶、在位内膜以及阴道磷酸化p65(p-p65)、PKCepsilon和TRPV1的表达。结果 p50基因敲除小鼠异位病灶明显减小,并且,p50基因敲除小鼠异位病灶,在位内膜,以及阴道的p-p65 and PKCepsilon的表达也下降。结论 NF-kappaBp50亚单位在子宫内膜异位症的发生发展中起重要作用,可能是潜在的治疗靶标。展开更多
Summary: To determine the role of NF-kappaB in ischemia reperfusion (I/R) injury of the rat liver,rats underwent partial hepatic ischemia and reperfusion. The left and median lobes of the liver weresubjected to ischem...Summary: To determine the role of NF-kappaB in ischemia reperfusion (I/R) injury of the rat liver,rats underwent partial hepatic ischemia and reperfusion. The left and median lobes of the liver weresubjected to ischemia for 90 min followed by reperfusion for defined times. NF-kappaB activity wasanalyzed by electrophoretic mobility shift assay (EMSA). Semiquantitative reverse-transcriptasepolymerase chain reaction was used to analyze TNF-α and ICAM-1 mRNA levels. Results showedduring liver I/R injury, NF-kappaB activation was induced in a time dependent manner. NF-kappaBwas activated within 1 h and 2 h after the initiation of reperfusion and decreased after 4 h. MessengerRNA expression of TNF-α and ICAM-1 were increased after the reperfusion of 2 h. It was concludedthat during hepatic I/R injury, NF-kappaB was activated and could bind to special sequence in thepromoters of budget genes, which can up-regulate the expression of TNF-α and ICAM-1 mRNA toresult in ishemia reperfusion injury of the rat liver.展开更多
NF-kappaB plays a critical role in cell survival,apoptosis,and inflammatory responses.Serine/threoninespecific phosphatases(PPs)represent the second major class of enzymes that catalyze the dephosphorylation of protei...NF-kappaB plays a critical role in cell survival,apoptosis,and inflammatory responses.Serine/threoninespecific phosphatases(PPs)represent the second major class of enzymes that catalyze the dephosphorylation of proteins.The roles of PPs regulating NF-kappaB activities are poorly understood.Here we describe an RNAi-based screen to identify the PPs that involve in regulating NFkappaB signaling.Thirty-four candidate PPs siRNAs were synthesized and primarily screened by NF-kappaB reporter gene assay in HeLa cells.PHLPP,one of the protein phosphatase type 2C family members(PP2C),was identified as a positive regulator of NF-kappaB signaling.Knock-down of PHLPP dramatically attenuated TNFα-stimulated NF-kappaB transcriptional activation.Knockdown of PHLPP led to enhancement of NF-kappaB/p65 nuclear import and retention,but decreased TNFα-induced phosphorylation at Ser276 on p65.This critical phosphorylation was also drastically reduced by knock-down of PKCalpha and Akt1,two important serine/threonine kinases dephosphorylated by PHLPP.The results together suggest that PHLPP-Akt-PKC may represent an important signaling loop that activates NF-kappaB/p65 signaling through critical serine phosphorylation.展开更多
文摘目的利用NF-kappaBp50基因敲除小鼠建立子宫内膜异位症模型探索NF-kappaBp50亚单位在子宫内膜异位症发生发展中的作用。方法利用子宫内膜移植法建立P50基因敲除小鼠及野生型对照小鼠的子宫内膜异位症动物模型,检测建模后异位病灶大小、免疫组化检测异位病灶、在位内膜以及阴道磷酸化p65(p-p65)、PKCepsilon和TRPV1的表达。结果 p50基因敲除小鼠异位病灶明显减小,并且,p50基因敲除小鼠异位病灶,在位内膜,以及阴道的p-p65 and PKCepsilon的表达也下降。结论 NF-kappaBp50亚单位在子宫内膜异位症的发生发展中起重要作用,可能是潜在的治疗靶标。
文摘Summary: To determine the role of NF-kappaB in ischemia reperfusion (I/R) injury of the rat liver,rats underwent partial hepatic ischemia and reperfusion. The left and median lobes of the liver weresubjected to ischemia for 90 min followed by reperfusion for defined times. NF-kappaB activity wasanalyzed by electrophoretic mobility shift assay (EMSA). Semiquantitative reverse-transcriptasepolymerase chain reaction was used to analyze TNF-α and ICAM-1 mRNA levels. Results showedduring liver I/R injury, NF-kappaB activation was induced in a time dependent manner. NF-kappaBwas activated within 1 h and 2 h after the initiation of reperfusion and decreased after 4 h. MessengerRNA expression of TNF-α and ICAM-1 were increased after the reperfusion of 2 h. It was concludedthat during hepatic I/R injury, NF-kappaB was activated and could bind to special sequence in thepromoters of budget genes, which can up-regulate the expression of TNF-α and ICAM-1 mRNA toresult in ishemia reperfusion injury of the rat liver.
基金This research was supported by the National High Technology Research and Development Program of China(863 Program)(No.2006AA02Z191),the Bureau of Science and Technology of Guangzhou,China(No.2007Z1-E4041)Guangzhou Economic&Technological Development District(GETDD S&T Project)(2007G-P029).
文摘NF-kappaB plays a critical role in cell survival,apoptosis,and inflammatory responses.Serine/threoninespecific phosphatases(PPs)represent the second major class of enzymes that catalyze the dephosphorylation of proteins.The roles of PPs regulating NF-kappaB activities are poorly understood.Here we describe an RNAi-based screen to identify the PPs that involve in regulating NFkappaB signaling.Thirty-four candidate PPs siRNAs were synthesized and primarily screened by NF-kappaB reporter gene assay in HeLa cells.PHLPP,one of the protein phosphatase type 2C family members(PP2C),was identified as a positive regulator of NF-kappaB signaling.Knock-down of PHLPP dramatically attenuated TNFα-stimulated NF-kappaB transcriptional activation.Knockdown of PHLPP led to enhancement of NF-kappaB/p65 nuclear import and retention,but decreased TNFα-induced phosphorylation at Ser276 on p65.This critical phosphorylation was also drastically reduced by knock-down of PKCalpha and Akt1,two important serine/threonine kinases dephosphorylated by PHLPP.The results together suggest that PHLPP-Akt-PKC may represent an important signaling loop that activates NF-kappaB/p65 signaling through critical serine phosphorylation.
