An increasing number of studies report that the Ras/Raf/extracellular signal-regulated kinase 1/2 （ERK1/2） signaling pathway has a death-promoting apoptotic function in neural cells. We hypothesized that the Ras/Raf...An increasing number of studies report that the Ras/Raf/extracellular signal-regulated kinase 1/2 （ERK1/2） signaling pathway has a death-promoting apoptotic function in neural cells. We hypothesized that the Ras/Raf/ERK1/2 signaling pathway may be abnormally regulated in rat injured spinal cord models. The weight drop method was used to establish rat spinal cord injury at T9. Western blot analysis and immunohistochemical staining revealed Ras expression was dramatically elevated, and the phosphorylations of A-Raf, B-Raf and C-Raf were all upregulated in the injured spinal cord. Both mitogen-activated protein kinase kinase 1/2 and ERK1/2, which belong to the Ras/Raf signaling kinases, were upregulated. These results indicate that Ras/Raf/ ERK1/2 signaling may be upregulated in injured spinal cord and are involved in recovery after spinal cord injury.展开更多
AIM:To explore the role and mechanisms of extracellular signal-regulated protein kinase-mitogen-activated protein kinase(ERK-MAPK) signaling in pentagastrinregulated growth of large intestinal carcinoma.METHODS:HT-29 ...AIM:To explore the role and mechanisms of extracellular signal-regulated protein kinase-mitogen-activated protein kinase(ERK-MAPK) signaling in pentagastrinregulated growth of large intestinal carcinoma.METHODS:HT-29 cells were incubated in different media and divided into the control group,pentagastrin group,proglumide group,and pentagastrin + proglumide group.No reagent was added to the control group,and other groups were incubated with reagent at different concentrations.Changes in proliferation of HT-29 cells were detected by MTT assay,and the optimal concentrations of pentagastrin and proglumide were determined.The changes in proliferation index(PI) and apoptosis rate(AR) of HT-29 cells were detected by Annexin V-fluorescein isothiocyanate flow cytometry.mRNA expression of pentagastrin receptor/cholecystokinin-B receptor(CCK-BR),ERK1/2 and K-ras were detected by reverse transcriptase polymerase chain reaction.The protein and phosphorylation level of ERK1/2 and K-ras were detected by western blotting.All data were analyzed by analysis of variance and SNK-q test.RESULTS:The proliferation of HT-29 cells was stimulated by pentagastrin at a concentration of 6.25-100 mg/L,and the optimal concentration of pentagastrin was 25.0 mg/L(F = 31.36,P < 0.05).Proglumide had no obvious effect on the proliferation of HT-29 cells,while it significantly inhibited the proliferation of HT-29 cells stimulated by pentagastrin when the concentration of proglumide was 8.0-128.0 mg/L,and the optimal concentration was 32.0 mg/L(F = 24.31,P < 0.05).The PI of the pentagastrin(25.0 mg/L) group was 37.5% ± 5.2%,which was significantly higher than 27.7% ± 5.0% of the control group and 27.3% ± 5.8% of the pentagastrin(25.0 mg/L) + proglumide(32.0 mg/L) group(Q = 4.56-4.75,P < 0.05).The AR of the pentagastrin(25.0 mg/L) group was 1.9% ± 0.4%,which was significantly lower than 2.5% ± 0.4% of the control group and 2.4% ± 0.3% of the pentagastrin(25.0 mg/L) + proglumide(32.0 mg/L) group(Q = 4.23-4.06,P < 0.05).mRNA expression of CCK-BR was detected in HT-29 cells.The phosphorylation levels of ERK1/2 protein and phosphorylated K-ras protein of the pentagastrin group were 0.43% ± 0.04% and 0.45% ± 0.06%,which were significantly higher than 0.32% ± 0.02% and 0.31% ± 0.05% of the control group(Q = 7.78-4.95,P < 0.05),and 0.36% ± 0.01% and 0.35% ± 0.04% of the pentagastrin + proglumide group(Q = 5.72-4.08,P < 0.05).There were no significant differences in the mRNA and protein expression of ERK1/2 and K-ras among the control,pentagastrin,proglumide and pentagastrin + proglumide groups(F = 0.52,0.72,0.78,0.28;P > 0.05).CONCLUSION:Gastrin stimulates proliferation of HT-29 cells and inhibits apoptosis by upregulating phosphorylation of ERK and K-ras through the Ras-Raf-MEK1/2-ERK1/2 pathway,and this is restrained by proglumide.展开更多
目的:探讨化瘀通络中药对肝纤维化(hepatic fibrosis,HF)的可能作用机制.方法:四氯化碳(carbon tetrachloride,CCl4)皮下注射的方法建立HF大鼠模型,将其随机分为对照组、模型组、中药低、中、高剂量组.造模开始时中药低、中、高剂量组...目的:探讨化瘀通络中药对肝纤维化(hepatic fibrosis,HF)的可能作用机制.方法:四氯化碳(carbon tetrachloride,CCl4)皮下注射的方法建立HF大鼠模型,将其随机分为对照组、模型组、中药低、中、高剂量组.造模开始时中药低、中、高剂量组大鼠分别给予化瘀通络中药鳖甲煎丸0.55、1.10、2.20 g/(kg?d)灌胃,正常对照组及模型组给予等体积的生理盐水灌胃,共6 wk.成模后继续灌胃5 wk.于第11周末,观察各组大鼠肝脏病理形态学变化;RT-PCR法检测肝组织中血小板衍生生长因子(platelet derivative growth factor,PDGF)、Ras基因表达水平;免疫组织化学方法检测肝组织细胞外信号调节激酶(extracellular signal regulated kinase,ERK1)蛋白表达.结果:与对照组相比,模型组大鼠肝组织PDGF、Ras、ERK1蛋白表达明显升高(0.190±0.001 vs 0.710±0.018,0.120±0.000 vs 0.420±0.006,0.120±0.000 vs 0.440±0.017,P<0.05);与模型组相比,化瘀通络中药鳖甲煎丸能够显著减轻HF大鼠肝脏组织病理损害,下调PDGF、Ras、ERK1蛋白的表达,其中以高剂量组效果最为显著.结论:鳖甲煎丸可明显减轻HF的病理损害,这一作用的实现可能是通过PDGF介导的Ras/ERK信号转导通路实现的.展开更多
Objective The rostral anterior cingulate cortex （rACC） is implicated in processing the emotional component of pain. N-methyl-D-aspartate receptors （NMDARs） are highly expressed in the rACC and mediate painrelated ...Objective The rostral anterior cingulate cortex （rACC） is implicated in processing the emotional component of pain. N-methyl-D-aspartate receptors （NMDARs） are highly expressed in the rACC and mediate painrelated affect by activating a signaling pathway that involves cyclic adenosine monophosphate （cAMP）/protein ki- nase A （PKA） and/or extracellular regulated kinase （ERK）/cAMP-response element-binding protein （CREB）. The present study investigated the contributions of the NMDAR glycine site and GluN2B subunit to the activation of ERK and CREB both in vitro and in vivo in rat rACC. Methods Immunohistochemistry and Western blot analy- sis were used to separately assess the expression of phospho-ERK （pERK） and phospho-CREB （pCREB） in vitro and in vivo. Double immunostaining was also used to determine the colocalization of pERK and pCREB. Results Both bath application of NMDA in brain slices in vitro and intraplantar injection of formalin into the rat hindpaw in vivo induced significant up-regulation of pERK and pCREB in the rACC, which was inhibited by the NMDAR antago- nist DL-2-amino-5-phospho-novaleric acid. Selective blockade of the NMDAR GluN2B subunit and the glycine- binding site, or degradation of endogenous D-serine, a co-agonist for the glycine site, significantly decreased the up- regulation of pERK and pCREB expression in the rACC. Further, the activated ERK predominantly colocalized with CREB. Conclusion Either the glycine site or the GluN2B subunit of NMDARs participates in the phosphorylation of ERK and CREB induced by bath application of NMDA in brain slices or hindpaw injection of 5% formalin in rats, and these might be fundamental molecular mechanisms underlying pain affect.展开更多
Throughout the globe,diabetes mellitus（DM） is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and af...Throughout the globe,diabetes mellitus（DM） is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and affects all components of the central and peripheral nervous systems that can range from dementia to diabetic neuropathy.The mechanistic target of rapamycin（m TOR） is a promising agent for the development of novel regenerative strategies for the treatment of DM.m TOR and its related signaling pathways impact multiple metabolic parameters that include cellular metabolic homeostasis,insulin resistance,insulin secretion,stem cell proliferation and differentiation,pancreatic β-cell function,and programmed cell death with apoptosis and autophagy.m TOR is central element for the protein complexes m TOR Complex 1（m TORC1） and m TOR Complex 2（m TORC2） and is a critical component for a number of signaling pathways that involve phosphoinositide 3-kinase（PI 3-K）,protein kinase B（Akt）,AMP activated protein kinase（AMPK）,silent mating type information regulation 2 homolog 1（Saccharomyces cerevisiae）（SIRT1）,Wnt1 inducible signaling pathway protein 1（WISP1）,and growth factors.As a result,m TOR represents an exciting target to offer new clinical avenues for the treatment of DM and the complications of this disease.Future studies directed to elucidate the delicate balance m TOR holds over cellular metabolism and the impact of its broad signaling pathways should foster the translation of these targets into effective clinical regimens for DM.展开更多
Overexpression of receptor-interacting protein 140（RIP140） promotes neuronal differentiation of N2 a cells via extracellular regulated kinase 1/2（ERK1/2） signaling.However,involvement of RIP140 in human neural dif...Overexpression of receptor-interacting protein 140（RIP140） promotes neuronal differentiation of N2 a cells via extracellular regulated kinase 1/2（ERK1/2） signaling.However,involvement of RIP140 in human neural differentiation remains unclear.We found both RIP140 and ERK1/2 expression increased during neural differentiation of H1 human embryonic stem cells.Moreover,RIP140 negatively correlated with stem cell markers Oct4 and Sox2 during early stages of neural differentiation,and positively correlated with the neural stem cell marker Nestin during later stages.Thus,ERK1/2 signaling may provide the molecular mechanism by which RIP140 takes part in neural differentiation to eventually affect the number of neurons produced.展开更多
Objective： To study the mechanism underlying the inhibitory effect of Qingluo Tongbi Granule （清络通痹颗粒, QTG） on osteoclast differentiation in rheumatoid arthritis in rats. Methods： Fibroblast and monocyte co-c...Objective： To study the mechanism underlying the inhibitory effect of Qingluo Tongbi Granule （清络通痹颗粒, QTG） on osteoclast differentiation in rheumatoid arthritis in rats. Methods： Fibroblast and monocyte co-culture were used to induce osteoclast differentiation in adjuvant-induced arthritic （AIA） rats. Serum containing QTG was prepared and added to the osteoclasts, and activation of the tumor necrosis factor receptorassociated factor 6/mitogen-activated protein kinase/nuclear factor of activated T cells, cytoplasmic1 （TRAF6/ MAPK/NFATcl） pathways was examined. Results： The induced osteoclasts were multinucleated and stained positive for tartrate-resistant acid phosphatase （TRAP） staining. Serum containing QTG at 14.4, 7.2 or 3.6 g/kg inhibited the activation of TRAF6, extracellular regulated protein kinase （ERK）1/2, c-Jun N-terminal kinase （JNK） and p38 and decreased the percentage of cells with nuclear NFATcl in a dose-dependent manner, the high and middle doses exhibited clear inhibitory activity （P〈0.01 and P〈0.05, respectively）. After the addition of MAPK inhibitors, the NFATcl expression showed no significant difference compared with the control group （P〉0.05）. Conclusions： Serum containing QTG could generally inhibit the TRAF6/MAPK pathways and possibly inhibit the NFATcl pathway. In addition, QTG may regulate other signaling pathways that are related to osteoclast differentiation and maturation.展开更多
基金funded by the National Natural Science Foundation for Young Scholars of China,No.81101362 and 81401784the Key Project of National Natural Science Foundation of China,No.81330042
文摘An increasing number of studies report that the Ras/Raf/extracellular signal-regulated kinase 1/2 （ERK1/2） signaling pathway has a death-promoting apoptotic function in neural cells. We hypothesized that the Ras/Raf/ERK1/2 signaling pathway may be abnormally regulated in rat injured spinal cord models. The weight drop method was used to establish rat spinal cord injury at T9. Western blot analysis and immunohistochemical staining revealed Ras expression was dramatically elevated, and the phosphorylations of A-Raf, B-Raf and C-Raf were all upregulated in the injured spinal cord. Both mitogen-activated protein kinase kinase 1/2 and ERK1/2, which belong to the Ras/Raf signaling kinases, were upregulated. These results indicate that Ras/Raf/ ERK1/2 signaling may be upregulated in injured spinal cord and are involved in recovery after spinal cord injury.
基金Supported by Natural Science Foundation of Anhui Province,No.1408085MH148Natural Science Fund of Education Bureau of Anhui Province,No.kj2010b242+1 种基金Natural Science Fund of Wannan Medical College,No.wk2012zf02the key science and technology project of Wuhu City,No.health-2-4
文摘AIM:To explore the role and mechanisms of extracellular signal-regulated protein kinase-mitogen-activated protein kinase(ERK-MAPK) signaling in pentagastrinregulated growth of large intestinal carcinoma.METHODS:HT-29 cells were incubated in different media and divided into the control group,pentagastrin group,proglumide group,and pentagastrin + proglumide group.No reagent was added to the control group,and other groups were incubated with reagent at different concentrations.Changes in proliferation of HT-29 cells were detected by MTT assay,and the optimal concentrations of pentagastrin and proglumide were determined.The changes in proliferation index(PI) and apoptosis rate(AR) of HT-29 cells were detected by Annexin V-fluorescein isothiocyanate flow cytometry.mRNA expression of pentagastrin receptor/cholecystokinin-B receptor(CCK-BR),ERK1/2 and K-ras were detected by reverse transcriptase polymerase chain reaction.The protein and phosphorylation level of ERK1/2 and K-ras were detected by western blotting.All data were analyzed by analysis of variance and SNK-q test.RESULTS:The proliferation of HT-29 cells was stimulated by pentagastrin at a concentration of 6.25-100 mg/L,and the optimal concentration of pentagastrin was 25.0 mg/L(F = 31.36,P < 0.05).Proglumide had no obvious effect on the proliferation of HT-29 cells,while it significantly inhibited the proliferation of HT-29 cells stimulated by pentagastrin when the concentration of proglumide was 8.0-128.0 mg/L,and the optimal concentration was 32.0 mg/L(F = 24.31,P < 0.05).The PI of the pentagastrin(25.0 mg/L) group was 37.5% ± 5.2%,which was significantly higher than 27.7% ± 5.0% of the control group and 27.3% ± 5.8% of the pentagastrin(25.0 mg/L) + proglumide(32.0 mg/L) group(Q = 4.56-4.75,P < 0.05).The AR of the pentagastrin(25.0 mg/L) group was 1.9% ± 0.4%,which was significantly lower than 2.5% ± 0.4% of the control group and 2.4% ± 0.3% of the pentagastrin(25.0 mg/L) + proglumide(32.0 mg/L) group(Q = 4.23-4.06,P < 0.05).mRNA expression of CCK-BR was detected in HT-29 cells.The phosphorylation levels of ERK1/2 protein and phosphorylated K-ras protein of the pentagastrin group were 0.43% ± 0.04% and 0.45% ± 0.06%,which were significantly higher than 0.32% ± 0.02% and 0.31% ± 0.05% of the control group(Q = 7.78-4.95,P < 0.05),and 0.36% ± 0.01% and 0.35% ± 0.04% of the pentagastrin + proglumide group(Q = 5.72-4.08,P < 0.05).There were no significant differences in the mRNA and protein expression of ERK1/2 and K-ras among the control,pentagastrin,proglumide and pentagastrin + proglumide groups(F = 0.52,0.72,0.78,0.28;P > 0.05).CONCLUSION:Gastrin stimulates proliferation of HT-29 cells and inhibits apoptosis by upregulating phosphorylation of ERK and K-ras through the Ras-Raf-MEK1/2-ERK1/2 pathway,and this is restrained by proglumide.
文摘目的:探讨化瘀通络中药对肝纤维化(hepatic fibrosis,HF)的可能作用机制.方法:四氯化碳(carbon tetrachloride,CCl4)皮下注射的方法建立HF大鼠模型,将其随机分为对照组、模型组、中药低、中、高剂量组.造模开始时中药低、中、高剂量组大鼠分别给予化瘀通络中药鳖甲煎丸0.55、1.10、2.20 g/(kg?d)灌胃,正常对照组及模型组给予等体积的生理盐水灌胃,共6 wk.成模后继续灌胃5 wk.于第11周末,观察各组大鼠肝脏病理形态学变化;RT-PCR法检测肝组织中血小板衍生生长因子(platelet derivative growth factor,PDGF)、Ras基因表达水平;免疫组织化学方法检测肝组织细胞外信号调节激酶(extracellular signal regulated kinase,ERK1)蛋白表达.结果:与对照组相比,模型组大鼠肝组织PDGF、Ras、ERK1蛋白表达明显升高(0.190±0.001 vs 0.710±0.018,0.120±0.000 vs 0.420±0.006,0.120±0.000 vs 0.440±0.017,P<0.05);与模型组相比,化瘀通络中药鳖甲煎丸能够显著减轻HF大鼠肝脏组织病理损害,下调PDGF、Ras、ERK1蛋白的表达,其中以高剂量组效果最为显著.结论:鳖甲煎丸可明显减轻HF的病理损害,这一作用的实现可能是通过PDGF介导的Ras/ERK信号转导通路实现的.
基金supported by the National Natural Science Foundation of China (30900444,31070973,30870835,31121061 and 30830044)
文摘Objective The rostral anterior cingulate cortex （rACC） is implicated in processing the emotional component of pain. N-methyl-D-aspartate receptors （NMDARs） are highly expressed in the rACC and mediate painrelated affect by activating a signaling pathway that involves cyclic adenosine monophosphate （cAMP）/protein ki- nase A （PKA） and/or extracellular regulated kinase （ERK）/cAMP-response element-binding protein （CREB）. The present study investigated the contributions of the NMDAR glycine site and GluN2B subunit to the activation of ERK and CREB both in vitro and in vivo in rat rACC. Methods Immunohistochemistry and Western blot analy- sis were used to separately assess the expression of phospho-ERK （pERK） and phospho-CREB （pCREB） in vitro and in vivo. Double immunostaining was also used to determine the colocalization of pERK and pCREB. Results Both bath application of NMDA in brain slices in vitro and intraplantar injection of formalin into the rat hindpaw in vivo induced significant up-regulation of pERK and pCREB in the rACC, which was inhibited by the NMDAR antago- nist DL-2-amino-5-phospho-novaleric acid. Selective blockade of the NMDAR GluN2B subunit and the glycine- binding site, or degradation of endogenous D-serine, a co-agonist for the glycine site, significantly decreased the up- regulation of pERK and pCREB expression in the rACC. Further, the activated ERK predominantly colocalized with CREB. Conclusion Either the glycine site or the GluN2B subunit of NMDARs participates in the phosphorylation of ERK and CREB induced by bath application of NMDA in brain slices or hindpaw injection of 5% formalin in rats, and these might be fundamental molecular mechanisms underlying pain affect.
基金supported by American Diabetes Association,American Heart Association,NIH NIEHS,NIH NIA,NIH NINDS,and NIH ARRA
文摘Throughout the globe,diabetes mellitus（DM） is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and affects all components of the central and peripheral nervous systems that can range from dementia to diabetic neuropathy.The mechanistic target of rapamycin（m TOR） is a promising agent for the development of novel regenerative strategies for the treatment of DM.m TOR and its related signaling pathways impact multiple metabolic parameters that include cellular metabolic homeostasis,insulin resistance,insulin secretion,stem cell proliferation and differentiation,pancreatic β-cell function,and programmed cell death with apoptosis and autophagy.m TOR is central element for the protein complexes m TOR Complex 1（m TORC1） and m TOR Complex 2（m TORC2） and is a critical component for a number of signaling pathways that involve phosphoinositide 3-kinase（PI 3-K）,protein kinase B（Akt）,AMP activated protein kinase（AMPK）,silent mating type information regulation 2 homolog 1（Saccharomyces cerevisiae）（SIRT1）,Wnt1 inducible signaling pathway protein 1（WISP1）,and growth factors.As a result,m TOR represents an exciting target to offer new clinical avenues for the treatment of DM and the complications of this disease.Future studies directed to elucidate the delicate balance m TOR holds over cellular metabolism and the impact of its broad signaling pathways should foster the translation of these targets into effective clinical regimens for DM.
基金supported by the National Natural Science Foundation of China,No.31340024
文摘Overexpression of receptor-interacting protein 140（RIP140） promotes neuronal differentiation of N2 a cells via extracellular regulated kinase 1/2（ERK1/2） signaling.However,involvement of RIP140 in human neural differentiation remains unclear.We found both RIP140 and ERK1/2 expression increased during neural differentiation of H1 human embryonic stem cells.Moreover,RIP140 negatively correlated with stem cell markers Oct4 and Sox2 during early stages of neural differentiation,and positively correlated with the neural stem cell marker Nestin during later stages.Thus,ERK1/2 signaling may provide the molecular mechanism by which RIP140 takes part in neural differentiation to eventually affect the number of neurons produced.
基金Supported by the National Natural Science Foundation of China(No.81072749)the Ministry of Education of Overseas Returnees Research Fund(No.2006331)+3 种基金Six Talent Peaks Subject of Jiangsu Province(No.2007)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(No.20116)Jiangsu Province Ordinary University Innovative Research ProjectOrdinary University Innovative Research Project of Jiangsu Province(No.2011)
文摘Objective： To study the mechanism underlying the inhibitory effect of Qingluo Tongbi Granule （清络通痹颗粒, QTG） on osteoclast differentiation in rheumatoid arthritis in rats. Methods： Fibroblast and monocyte co-culture were used to induce osteoclast differentiation in adjuvant-induced arthritic （AIA） rats. Serum containing QTG was prepared and added to the osteoclasts, and activation of the tumor necrosis factor receptorassociated factor 6/mitogen-activated protein kinase/nuclear factor of activated T cells, cytoplasmic1 （TRAF6/ MAPK/NFATcl） pathways was examined. Results： The induced osteoclasts were multinucleated and stained positive for tartrate-resistant acid phosphatase （TRAP） staining. Serum containing QTG at 14.4, 7.2 or 3.6 g/kg inhibited the activation of TRAF6, extracellular regulated protein kinase （ERK）1/2, c-Jun N-terminal kinase （JNK） and p38 and decreased the percentage of cells with nuclear NFATcl in a dose-dependent manner, the high and middle doses exhibited clear inhibitory activity （P〈0.01 and P〈0.05, respectively）. After the addition of MAPK inhibitors, the NFATcl expression showed no significant difference compared with the control group （P〉0.05）. Conclusions： Serum containing QTG could generally inhibit the TRAF6/MAPK pathways and possibly inhibit the NFATcl pathway. In addition, QTG may regulate other signaling pathways that are related to osteoclast differentiation and maturation.
