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
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 were subjected to ischemia for ...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 were subjected to ischemia for 90 min followed by reperfusion for defined times. NF-kappaB activity was analyzed by electrophoretic mobility shift assay (EMSA). Semiquantitative reverse-transcriptase polymerase chain reaction was used to analyze TNF-α and ICAM-1 mRNA levels. Results showed during liver I/R injury, NF-kappaB activation was induced in a time dependent manner. NF-kappaB was activated within 1h and 2h after the initiation of reperfusion and decreased after 4 h. Messenger RNA expression of TNF-α and ICAM-1 were increased after the reperfusion of 2 h. It was concluded that during hepatic I/R injury, NF-kappaB was activated and could bind to special sequence in the promoters of budget genes, which can up-regulate the expression of TNF-α and ICAM-1 mRNA to result in ischemia reperfusion injury of the rat liver.展开更多
Objective： To explore the role of activated liver X receptor α （LXRα） on the expressions of interleukin-1 receptor associated kinase-4 （IRAK-4） and NF-kappaB （NF-κB） in the inflammatory response which induce...Objective： To explore the role of activated liver X receptor α （LXRα） on the expressions of interleukin-1 receptor associated kinase-4 （IRAK-4） and NF-kappaB （NF-κB） in the inflammatory response which induced by LPS in the Kupffer cells and to investigate the possible mechanisms of LXRα negative regulation of inflammatory response. Methods： The Kupffer cells were isolated from male Kunming mice by collagen perfusion in situ. And these cells were divided into 4 groups： normal control group, LPS treatment group, LXRct agonist T0901317 treatment group, LPS and T0901317 combined treatment group. The LPS treatment group were treated with a final concentration of 1 μg/ml LPS in RPMI 1640 and cultured for 6 h, the T0901317 treatment group were treated with a final concentration of 5 μg/ml in RPMI 1640 and cultured for 24 h, and the combined treatment group received pre-culture for 24 h with a final concentration of 1μg/ml T0901317 in RPMI 1640 and then cultured for 6 h with a final concentration of 5 μg/ml LPS in RPMI 1640. All groups were cultured for 30 h. The expression of LXRα, IRAK-4 and NF-κB at mRNA and protein levels were detected by real-time PCR and Western blotting, and the TNF-α and IL-1β levels were detected by ELISA. Results： The levels of LXRα mRNA and protein were highest in T0901317 group, and lowest in LPS group （P〈0.05）. The level of IRAK4 and NF-κB mRNAs and proteins were evidently lower in the Combined-treated group than in LPS group （P〈0.05）. And the level of TNF-α and IL-1 were observed highest in LPS group （P〈0.05）, but no difference among the Control group, T0901317 group and Combined-treated group （P〉0.05）. Conclusion： These date suggest that the LXR agonists can effectively up-regulate the expressions of LXRα mRNA and protein and inhibit the inflammatory response. This may be via down-regulating the expressions of IRAK4 and NF-κB at mRNA and protein levels.展开更多
Objective To determine the role of the NF-kappaB/I-kappaB pathway during ischemia reperfusion (I/R) injury to rat liver. Methords A group of rats underwent partial hepatic ischemia and reperfusion. The left and medi...Objective To determine the role of the NF-kappaB/I-kappaB pathway during ischemia reperfusion (I/R) injury to rat liver. Methords A group of rats underwent partial hepatic ischemia and reperfusion. The left and median lobe of the liver was subjected to ischemia for 90 minutes followed by reperfusion for previously specified periods. NF-kappaB activity was analyzed by electrophoretic mobility shift assay (EMSA). The protein level of I-kappaB was assessed using Western blot analysis. A semiquantitative reverse transcriptase polymerase chain reaction was used to analyze TNF-α and ICAM-1 mRNA levels. Results During liver I/R injury,NF-kappaB activation was induced in a time-dependent fashion. NF-kappaB was activated within 1 hour and 2 hours after the initiation of reperfusion and decreased afer 4 hours. The I-kappaB protein level was decreased in the cytoplasm after 2 hours,and the messenger RNA expression of TNF-α and ICAM-1 were increased simultaneously. Conclusions The data suggest that I-kappaB protein was degraded during hepatic I/R injury,NF kappaB was realeased and bound to special sequence in the promoters of budget genes,which regulated the expression of TNF-α and ICAM-1 mRNA. This provides evidence that the NF-kappaB/I-kappaB pathway plays an important modulating role in the expression of proinflammatory genes relevant to the development of ischemia reperfusion injury.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 were subjected to ischemia for 90 min followed by reperfusion for defined times. NF-kappaB activity was analyzed by electrophoretic mobility shift assay (EMSA). Semiquantitative reverse-transcriptase polymerase chain reaction was used to analyze TNF-α and ICAM-1 mRNA levels. Results showed during liver I/R injury, NF-kappaB activation was induced in a time dependent manner. NF-kappaB was activated within 1h and 2h after the initiation of reperfusion and decreased after 4 h. Messenger RNA expression of TNF-α and ICAM-1 were increased after the reperfusion of 2 h. It was concluded that during hepatic I/R injury, NF-kappaB was activated and could bind to special sequence in the promoters of budget genes, which can up-regulate the expression of TNF-α and ICAM-1 mRNA to result in ischemia reperfusion injury of the rat liver.
基金the National Natural Science Foundation of China (30530360 and 30772098)
文摘Objective： To explore the role of activated liver X receptor α （LXRα） on the expressions of interleukin-1 receptor associated kinase-4 （IRAK-4） and NF-kappaB （NF-κB） in the inflammatory response which induced by LPS in the Kupffer cells and to investigate the possible mechanisms of LXRα negative regulation of inflammatory response. Methods： The Kupffer cells were isolated from male Kunming mice by collagen perfusion in situ. And these cells were divided into 4 groups： normal control group, LPS treatment group, LXRct agonist T0901317 treatment group, LPS and T0901317 combined treatment group. The LPS treatment group were treated with a final concentration of 1 μg/ml LPS in RPMI 1640 and cultured for 6 h, the T0901317 treatment group were treated with a final concentration of 5 μg/ml in RPMI 1640 and cultured for 24 h, and the combined treatment group received pre-culture for 24 h with a final concentration of 1μg/ml T0901317 in RPMI 1640 and then cultured for 6 h with a final concentration of 5 μg/ml LPS in RPMI 1640. All groups were cultured for 30 h. The expression of LXRα, IRAK-4 and NF-κB at mRNA and protein levels were detected by real-time PCR and Western blotting, and the TNF-α and IL-1β levels were detected by ELISA. Results： The levels of LXRα mRNA and protein were highest in T0901317 group, and lowest in LPS group （P〈0.05）. The level of IRAK4 and NF-κB mRNAs and proteins were evidently lower in the Combined-treated group than in LPS group （P〈0.05）. And the level of TNF-α and IL-1 were observed highest in LPS group （P〈0.05）, but no difference among the Control group, T0901317 group and Combined-treated group （P〉0.05）. Conclusion： These date suggest that the LXR agonists can effectively up-regulate the expressions of LXRα mRNA and protein and inhibit the inflammatory response. This may be via down-regulating the expressions of IRAK4 and NF-κB at mRNA and protein levels.
文摘Objective To determine the role of the NF-kappaB/I-kappaB pathway during ischemia reperfusion (I/R) injury to rat liver. Methords A group of rats underwent partial hepatic ischemia and reperfusion. The left and median lobe of the liver was subjected to ischemia for 90 minutes followed by reperfusion for previously specified periods. NF-kappaB activity was analyzed by electrophoretic mobility shift assay (EMSA). The protein level of I-kappaB was assessed using Western blot analysis. A semiquantitative reverse transcriptase polymerase chain reaction was used to analyze TNF-α and ICAM-1 mRNA levels. Results During liver I/R injury,NF-kappaB activation was induced in a time-dependent fashion. NF-kappaB was activated within 1 hour and 2 hours after the initiation of reperfusion and decreased afer 4 hours. The I-kappaB protein level was decreased in the cytoplasm after 2 hours,and the messenger RNA expression of TNF-α and ICAM-1 were increased simultaneously. Conclusions The data suggest that I-kappaB protein was degraded during hepatic I/R injury,NF kappaB was realeased and bound to special sequence in the promoters of budget genes,which regulated the expression of TNF-α and ICAM-1 mRNA. This provides evidence that the NF-kappaB/I-kappaB pathway plays an important modulating role in the expression of proinflammatory genes relevant to the development of ischemia reperfusion injury.
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.
