Mixed lineage kinase 3 （MLK3） is a mitogen-activated protein kinase kinase kinase that is activated by tumor necrosis factor-α （TNF-α） and specifically activates c-Jun N-terminal kinase （JNK） on TNF-a stimulat...Mixed lineage kinase 3 （MLK3） is a mitogen-activated protein kinase kinase kinase that is activated by tumor necrosis factor-α （TNF-α） and specifically activates c-Jun N-terminal kinase （JNK） on TNF-a stimulation. The mecha- nism by which TNF-α activates MLK3 is still not known. TNF receptor-associated factors （TRAFs） are adapter molecules that are recruited to cytoplasmic end of TNF receptor and mediate the downstream signaling, including activation of JNK. Here, we report that MLK3 associates with TRAF2, TRAF5 and TRAF6; however only TRAF2 can significantly induce the kinase activity of MLK3. The interaction domain of TRAF2 maps to the TRAF domain and for MLK3 to its C-terminal half （amino acids 511-847）. Endogenous TRAF2 and MLK3 associate with each other in response to TNF-α treatment in a time-dependent manner. The association between MLK3 and TRAF2 mediates MLK3 activation and competition with the TRAF2 deletion mutant that binds to MLK3 attenuates MLK3 kinase activity in a dose-dependent manner, on TNF-α treatment. Furthermore the downstream target of MLK3, JNK was activated by TNF-α in a TRAF2-dependent manner. Hence, our data show that the direct interaction between TRAF2 and MLK3 is required for TNF-α-induced activation of MLK3 and its downstream target, JNK.展开更多
Objective:To explore the effect of imbalance of tumor necrosis factor receptor related factor-6(TRAF-6),interleukin 1 receptor associated kinase-1(IRAK-1)and neutrophil alkaline phosphatase-3(NALP3)in patients with go...Objective:To explore the effect of imbalance of tumor necrosis factor receptor related factor-6(TRAF-6),interleukin 1 receptor associated kinase-1(IRAK-1)and neutrophil alkaline phosphatase-3(NALP3)in patients with gouty arthritis.Methods:The retrospective experiment was conducted on 105 patients with gouty arthritis admitted to our hospital(47 patients with acute onset and 58 patients with remission,namely group A and group B);meanwhile,another 61 healthy volunteers were selected for control,namely group C.The enrolling of the three groups was dated from May 2017 to May 2018,and TRAF-6,IRAK-1 and NALP3 of all subjects were tested through real-time fluorescence quantification(RT-PCR),and the correlation between the three inflammatory factors and gouty arthritis was compared.Results:1)Through treatment,ESR,BUA and total addiment in group A and B were higher than those in group C,among which the three indicators in group A were higher than those in group B(P<0.05),while CRP was lower than that of group C,and the two indicators in group A were lower than those in group B(P<0.05).2)There was no significant difference in the relative expression of TRAF-6 mRNA between group A and group B before treatment(P>0.05),significantly lower than group C(P<0.05);the above indicators of group A and group B were improved to some extent after treatment,but group A was still lower than group B(P<0.05),and the degree of improvement of group A was also lower than that of group C(P<0.05),while the degree of improvement of group B was not significantly different from that of group C(P>0.05).3)The relative expression level of IRAK-1mRNA in group A and group B before treatment showed no significant difference(P>0.05),but was also lower than that in group C(P<0.05).The relative expression level of IRAK-1mRNA in group A and group B increased to some extent after treatment,with group A significantly lower than group C(P<0.05),and group B showed no significant difference compared with group C(P>0.05).4)The relative expression level of NALP-3 mRNA in group A and group B showed no significant difference(P>0.05)before treatment,significantly higher than that in group C(P<0.05);the relative expression of NALP-3 mRNA in group A was not significantly decreased(P>0.05)after treatment,while that in group B was significantly decreased after treatment(P<0.05),indicating significant different compared with group A and group C.5)There was no correlation between)TRAF-6,ESR,CRP and total addiment(P>0.05);IRAK-1 was negatively correlated with CRP,BUA and total addiment(P<0.05);NALP-3 was negatively correlated with ESR and CRP(P<0.05).Conclusion:TRAF-6,IRAK-1 and NALP-3 are all under abnormal expression in the developing of new gouty arthritis,acting as important participants in promoting the occurrence,development and outcome of illness states,so the intervening measures should be taken.展开更多
Objective:This study aimed to evaluate the anti-inflammatory effects of petal and stamen extracts of saffron crocus(Crocus sativus)and explore the underlying mechanism.Methods:Local and systemic inflammation models we...Objective:This study aimed to evaluate the anti-inflammatory effects of petal and stamen extracts of saffron crocus(Crocus sativus)and explore the underlying mechanism.Methods:Local and systemic inflammation models were used to investigate the anti-inflammatory effects of C.sativus.A xyleneinduced inflammation model or lipopolysaccharide(LPS)-induced inflammation model was used in this study.C.sativus petal and stamen extracts were each administered to the mice in the xylene and LPS models by gavage for 14 d at 0.1 and 0.4 g/kg doses,respectively.Enzyme-linked immunosorbent assay(ELISA)was used to measure the concentrations of tumor necrosis factor(TNF)-αand interleukin(IL)-1βin mouse serum.Hematoxylin and eosin(H&E)staining was used to observe the pathological changes in the ear in the xylene-induced inflammation model and in the spleen in the LPS-induced inflammation model.NOD-like receptor thermal protein domain associated protein 3(NLRP3)protein levels within the nuclear factor-kappa B(NF-κB)pathway were assessed using western blotting.RAW264.7 cells were treated with LPS(5μg/mL)and LPS+C.sativus(0.05,0.1,and 0.2 mg/mL)for 24 h,and a Cell Counting Kit-8 was used to measure cell proliferation.Changes in NLRP3 and NF-κB levels were evaluated by western blotting.Results:Petal and stamen extracts of C.sativus attenuated the anti-inflammatory effects in local or systemic inflammatory models and repaired pathological changes in the ear in the xylene-induced inflammation model and spleen in the LPS-induced inflammation model.These extracts also decreased the concentrations of TNF-αand IL-1βin the mouse serum in the LPS-induced inflammation model.C.sativus downregulated NLRP3 protein level through the NF-κB pathway and downregulated LC-3 and BECLIN1 in vivo and in vitro.Carbonyl Cyanide3-ChloroPhenylhydrazone(CCCP)weakened the effects of C.sativus on the NLRP3–NF-κB pathway.Conclusion:C.sativus has anti-inflammatory effects and regulates the NLRP3-NF-κB pathway.展开更多
目的体外HepG2细胞培养观察芒果苷(mangiferin)对多耐药相关蛋白3(multidrug resistance-associate protein 3,MRP3)和核受体孕烷X受体(pregnane X receptor,PXR)、CYP7A启动子结合因子(CYP7A promoter-binding factor,CPF)表达的影响...目的体外HepG2细胞培养观察芒果苷(mangiferin)对多耐药相关蛋白3(multidrug resistance-associate protein 3,MRP3)和核受体孕烷X受体(pregnane X receptor,PXR)、CYP7A启动子结合因子(CYP7A promoter-binding factor,CPF)表达的影响。方法用芒果苷刺激HepG2细胞72 h后,分别抽提细胞RNA、膜蛋白及核蛋白,采用半定量RT-PCR和蛋白免疫印迹检测膜转运蛋白MRP3和核受体PXR、CPF在转录与蛋白水平的表达变化。熊脱氧胆酸(ursode-oxycholic acid,UDCA)处理的HepG2细胞作为阳性对照、DMSO处理细胞为阴性对照。结果芒果苷可显著刺激HepG2细胞膜转运蛋白MRP3的mRNA(比阴性对照组高3.0倍,P<0.05)和蛋白(比阴性对照组高3.3倍,P<0.05)表达,其作用强于UDCA。芒果苷也可明显上调核受体PXR[mRNA水平增高1.7倍(P<0.05),蛋白水平增高3.7倍(P<0.01)]、CPF[mRNA水平增高2.1倍(P<0.05),蛋白水平增高4.9倍(P<0.05)]的表达。结论芒果苷刺激肝癌细胞HepG2细胞膜转运蛋白MRP3的表达上调可能与核受体PXR、CPF途径相关。展开更多
文摘Mixed lineage kinase 3 （MLK3） is a mitogen-activated protein kinase kinase kinase that is activated by tumor necrosis factor-α （TNF-α） and specifically activates c-Jun N-terminal kinase （JNK） on TNF-a stimulation. The mecha- nism by which TNF-α activates MLK3 is still not known. TNF receptor-associated factors （TRAFs） are adapter molecules that are recruited to cytoplasmic end of TNF receptor and mediate the downstream signaling, including activation of JNK. Here, we report that MLK3 associates with TRAF2, TRAF5 and TRAF6; however only TRAF2 can significantly induce the kinase activity of MLK3. The interaction domain of TRAF2 maps to the TRAF domain and for MLK3 to its C-terminal half （amino acids 511-847）. Endogenous TRAF2 and MLK3 associate with each other in response to TNF-α treatment in a time-dependent manner. The association between MLK3 and TRAF2 mediates MLK3 activation and competition with the TRAF2 deletion mutant that binds to MLK3 attenuates MLK3 kinase activity in a dose-dependent manner, on TNF-α treatment. Furthermore the downstream target of MLK3, JNK was activated by TNF-α in a TRAF2-dependent manner. Hence, our data show that the direct interaction between TRAF2 and MLK3 is required for TNF-α-induced activation of MLK3 and its downstream target, JNK.
基金General project of science and technology development fund of Nanjing medical university (NMUB2018163)
文摘Objective:To explore the effect of imbalance of tumor necrosis factor receptor related factor-6(TRAF-6),interleukin 1 receptor associated kinase-1(IRAK-1)and neutrophil alkaline phosphatase-3(NALP3)in patients with gouty arthritis.Methods:The retrospective experiment was conducted on 105 patients with gouty arthritis admitted to our hospital(47 patients with acute onset and 58 patients with remission,namely group A and group B);meanwhile,another 61 healthy volunteers were selected for control,namely group C.The enrolling of the three groups was dated from May 2017 to May 2018,and TRAF-6,IRAK-1 and NALP3 of all subjects were tested through real-time fluorescence quantification(RT-PCR),and the correlation between the three inflammatory factors and gouty arthritis was compared.Results:1)Through treatment,ESR,BUA and total addiment in group A and B were higher than those in group C,among which the three indicators in group A were higher than those in group B(P<0.05),while CRP was lower than that of group C,and the two indicators in group A were lower than those in group B(P<0.05).2)There was no significant difference in the relative expression of TRAF-6 mRNA between group A and group B before treatment(P>0.05),significantly lower than group C(P<0.05);the above indicators of group A and group B were improved to some extent after treatment,but group A was still lower than group B(P<0.05),and the degree of improvement of group A was also lower than that of group C(P<0.05),while the degree of improvement of group B was not significantly different from that of group C(P>0.05).3)The relative expression level of IRAK-1mRNA in group A and group B before treatment showed no significant difference(P>0.05),but was also lower than that in group C(P<0.05).The relative expression level of IRAK-1mRNA in group A and group B increased to some extent after treatment,with group A significantly lower than group C(P<0.05),and group B showed no significant difference compared with group C(P>0.05).4)The relative expression level of NALP-3 mRNA in group A and group B showed no significant difference(P>0.05)before treatment,significantly higher than that in group C(P<0.05);the relative expression of NALP-3 mRNA in group A was not significantly decreased(P>0.05)after treatment,while that in group B was significantly decreased after treatment(P<0.05),indicating significant different compared with group A and group C.5)There was no correlation between)TRAF-6,ESR,CRP and total addiment(P>0.05);IRAK-1 was negatively correlated with CRP,BUA and total addiment(P<0.05);NALP-3 was negatively correlated with ESR and CRP(P<0.05).Conclusion:TRAF-6,IRAK-1 and NALP-3 are all under abnormal expression in the developing of new gouty arthritis,acting as important participants in promoting the occurrence,development and outcome of illness states,so the intervening measures should be taken.
基金supported by the National Natural Science Foundation of China(81873063)High-level talents Research project of Hefei Normal University(2020rcjj30)+2 种基金Key Project of Provincial Scientific Research Platform of Hefei Normal University in 2020(2020PTZD14)Key Project of Universities Natural Science Foundation of Anhui province(KJ2021A0935,KJ2021A0932)Innovation Team and Talents Cultivation Program of National Administration of Traditional Chinese Medicine(ZYYCXTD-C-202009).
文摘Objective:This study aimed to evaluate the anti-inflammatory effects of petal and stamen extracts of saffron crocus(Crocus sativus)and explore the underlying mechanism.Methods:Local and systemic inflammation models were used to investigate the anti-inflammatory effects of C.sativus.A xyleneinduced inflammation model or lipopolysaccharide(LPS)-induced inflammation model was used in this study.C.sativus petal and stamen extracts were each administered to the mice in the xylene and LPS models by gavage for 14 d at 0.1 and 0.4 g/kg doses,respectively.Enzyme-linked immunosorbent assay(ELISA)was used to measure the concentrations of tumor necrosis factor(TNF)-αand interleukin(IL)-1βin mouse serum.Hematoxylin and eosin(H&E)staining was used to observe the pathological changes in the ear in the xylene-induced inflammation model and in the spleen in the LPS-induced inflammation model.NOD-like receptor thermal protein domain associated protein 3(NLRP3)protein levels within the nuclear factor-kappa B(NF-κB)pathway were assessed using western blotting.RAW264.7 cells were treated with LPS(5μg/mL)and LPS+C.sativus(0.05,0.1,and 0.2 mg/mL)for 24 h,and a Cell Counting Kit-8 was used to measure cell proliferation.Changes in NLRP3 and NF-κB levels were evaluated by western blotting.Results:Petal and stamen extracts of C.sativus attenuated the anti-inflammatory effects in local or systemic inflammatory models and repaired pathological changes in the ear in the xylene-induced inflammation model and spleen in the LPS-induced inflammation model.These extracts also decreased the concentrations of TNF-αand IL-1βin the mouse serum in the LPS-induced inflammation model.C.sativus downregulated NLRP3 protein level through the NF-κB pathway and downregulated LC-3 and BECLIN1 in vivo and in vitro.Carbonyl Cyanide3-ChloroPhenylhydrazone(CCCP)weakened the effects of C.sativus on the NLRP3–NF-κB pathway.Conclusion:C.sativus has anti-inflammatory effects and regulates the NLRP3-NF-κB pathway.
文摘目的体外HepG2细胞培养观察芒果苷(mangiferin)对多耐药相关蛋白3(multidrug resistance-associate protein 3,MRP3)和核受体孕烷X受体(pregnane X receptor,PXR)、CYP7A启动子结合因子(CYP7A promoter-binding factor,CPF)表达的影响。方法用芒果苷刺激HepG2细胞72 h后,分别抽提细胞RNA、膜蛋白及核蛋白,采用半定量RT-PCR和蛋白免疫印迹检测膜转运蛋白MRP3和核受体PXR、CPF在转录与蛋白水平的表达变化。熊脱氧胆酸(ursode-oxycholic acid,UDCA)处理的HepG2细胞作为阳性对照、DMSO处理细胞为阴性对照。结果芒果苷可显著刺激HepG2细胞膜转运蛋白MRP3的mRNA(比阴性对照组高3.0倍,P<0.05)和蛋白(比阴性对照组高3.3倍,P<0.05)表达,其作用强于UDCA。芒果苷也可明显上调核受体PXR[mRNA水平增高1.7倍(P<0.05),蛋白水平增高3.7倍(P<0.01)]、CPF[mRNA水平增高2.1倍(P<0.05),蛋白水平增高4.9倍(P<0.05)]的表达。结论芒果苷刺激肝癌细胞HepG2细胞膜转运蛋白MRP3的表达上调可能与核受体PXR、CPF途径相关。
