Extracellular signal-regulated protein kinase 5 （ERK5）, also known as big mitogen-activated protein kinase 1 （MAPK1）, is an important member of ERK family, which is a subfamily of the large MAPK family. ERK5 is ex...Extracellular signal-regulated protein kinase 5 （ERK5）, also known as big mitogen-activated protein kinase 1 （MAPK1）, is an important member of ERK family, which is a subfamily of the large MAPK family. ERK5 is expressed in many tissues, including the dorsal root ganglion （DRG） neurons and the spinal cord. In this review, we focus on elaborating ERK5-associated pathway in pathological pain, in which the ERK5/CREB （cyclic adenosine monophos- phate （cAMP）-response element-binding protein） pathway plays a crucial role in the transduction of pain signal and contributes to pain hypersensitivity. ERK5 activation in the spinal dorsal horn occurs mainly in microglia. The activation of ERK5 can be mediated by N-methyI-D-aspartate （NMDA） receptors. We also elaborate the relationship between ERK5 activation and nerve growth factor-tyrosine kinase A （NGF-TrkA）, and the connection between ERK5 activation and brain-derived neurotrophic factor （BDNF） in pathological pain in detail.展开更多
Objective： Mitogen-activated protein kinases （MAPKs） are correlated with a more malignant phenotype in many cancers. This study was designed to evaluate the predictive value of the expression of MAPK phosphatase-1 ...Objective： Mitogen-activated protein kinases （MAPKs） are correlated with a more malignant phenotype in many cancers. This study was designed to evaluate the predictive value of the expression of MAPK phosphatase-1 （MKP-1） and phosphorylated extracellular signal-regulated kinase 1/2 （p-ERKl/2）, as the key regulatory mechanism of the MAPKs, in lung squamous cell carcinoma （SCC）. Methods： We assessed the expressions of MKP-1 and p-ERK1/2 in twenty subjects at different differentiation degree of SCC and five normal lungs by immunohistochemistry and real-time reverse transcriptase polymerase chain reaction （RT-PCR） analysis. Results： Immunohistochemistry and real-time RT-PCR assay showed that the expression of MKP-1 was gradually decreased as tissue type went from normal lung tissues to increasingly undifferentiated carcinoma, and it was negatively correlated with tumor differentiation （P〈0.01）. However, the expression of p-ERK1/2 or ERKl/2 was gradually increased as tissue type went from normal lung tissues to increasingly undifferentiated carcinoma, and it was positively correlated with tumor differentiation （P〈0.01）. Conclusions： Our data indicates the relevance of MKP-1 and p-ERK1/2 in SCC as a potential positive and negative prognostic factor. The imbalanced expression of MKP-1 and p-ERKl/2 may play a role in the development of SCC and these two molecules may be new targets for the therapy and prognosis of SCC.展开更多
Objective： To investigate the relationship between extracellular signal-regulated kinase （ERK） pathway, multidrug resistance gene （mdr-1）, ribonucleotide recluctase M1 （RRM1） gene and their roles in gemcitabine...Objective： To investigate the relationship between extracellular signal-regulated kinase （ERK） pathway, multidrug resistance gene （mdr-1）, ribonucleotide recluctase M1 （RRM1） gene and their roles in gemcitabine （GEM） chemoresistance in pancreatic cancer cell line SW1990. Methods： The GEM-resistance cell model was constructed by a stepwise method. Immunohistochemistry was used to measure the expression of ERK protein （ERK1/2） in the established cell strains in a semiquantitative way. The mRNA expression of mdr-1 and RRM1 were detected by RT-PCR. MTT assay was performed to determine the IC50 value. Results： The established GEM-resistant cell strains were able to gain stable growth and passage ability in the medium contained different concentration levels of GEM （0, 30, 60, 100, 150 and 200 nmol/L）. The expression of ERK protein, mdr-1 and RRM1 gene were elevated accompanied by the increase of GEM concentration. There was a highly positive correlation between mdr-1, RRM1 expression and GEM-resistanca level （r = 0.960, P = 0.002 and r = 0.966, P = 0.002）. The expression of ERK protein also correlated with the mdr-1 and RRM1 level （r = -0.943, P = 0.005 and r = -0.883, P = 0.02）. At the GEM-resistance level of 200 nmol/L, the grey scale value of ERK1/2 was 164.22 ±13.17, mdr-1/β-actin and RRM1/β-actin were 1.41 ±0.04 and 1.45 ± 0.18, respectively; after treated with ERK pathway inhibitor U0126, these values synchronously decreased to 186.85 ± 13.14, 0.2 3± 0.02 and 0.21 ± 0.03, respectively; inversely, the ERK1/2 grey scale value was 106.55 ± 16.45, mdr-l/β-actin and RRMl/β-actin were 1.50± 0.07 and 1.52 ± 0.12, respectively, which presented a tendency of synchronously increase after treated with ERK pathway activator EGF. The IC50 values in GEM-resistant cells of 0 nmol/L and 200 nmol/L levels were 4.104 and 10.20, respectively. After treated with U0126, these values decreased to 3.26 and 4.50, respectively; while treated with EGF, the IC50 values increased to 8.89 and 17.17, respectively. Conclusion： The ERK pathway may induce the GEM-chemoresistance in pancreatic cell line SW1990 through the participation in the regulation of the mdr-1 and RRM1 gene expression.展开更多
Objective： To examine modulations caused by cyclooxygenase-2 （COX-2） inhibitors on altered microenvironments and overbalanced neurotransmitters in pilocarpine-induced epileptic status rats and to investigate possib...Objective： To examine modulations caused by cyclooxygenase-2 （COX-2） inhibitors on altered microenvironments and overbalanced neurotransmitters in pilocarpine-induced epileptic status rats and to investigate possible mechanisms. Methods： Celecoxib （a COX-2 inhibitor） was administered 45 min prior to pilocarpine administration. The effects of COX-2 inhibitors on mlPSCs （miniature GABAergic inhibitory postsynaptic currents） of CA3 pyramidal cells in the hippocampus were recorded. Expressions of COX-2, c-Fos, newly generated neurons, and activated microgliosis were analyzed by immunohistochemistry, and expressions of c^-subunit of y-amino butyric acid （GABAA） receptors and mitogen-activated protein kinase/extracellular signal-regulated protein kinase （MAPK/ERK） activity were detected by Western blotting. Results： Pretreatment with celecoxib showed protection against pilocarpine-induced seizures. Celecoxib prevented microglia activation in the hilus and inhibited the abnormal neurogenesis and astrogliosis in the hippocampus by inhibiting MAPK/ERK activity and c-Fos transcription. Celecoxib also up-regulated the expression of GABAA receptors. NS-398 （N-2-cyclohexyloxy-4-nitrophenyl-methanesulfonamide）, another COX-2 inhibitor, enhanced the frequency and decay time of mIPSCs. Conclusion： The COX-2 inhibitor celecoxib decreased neuronal excitability and prevented epileptogenesis in pilocarpine-induced status epilepticus rats. Celecoxib regulates synaptic reorganization by inhibiting astrogliosis and ectopic neurogenesis by attenuating MAPK/ERK signal activity, mediated by a GABAergic mechanism.展开更多
The human immunodeficiency virus type 1 （HIV-1） can interact with and exploit the host cellular machinery to replicate and propagate itself. Numerous studies have shown that the Mitogen-activated protein kinase （M...The human immunodeficiency virus type 1 （HIV-1） can interact with and exploit the host cellular machinery to replicate and propagate itself. Numerous studies have shown that the Mitogen-activated protein kinase （MAPK） signal pathway can positively regulate the replication of HIV-1, but exactly how each MAPK pathway affects HIV-1 infection and replication is not understood. In this study, we used the Extracellular signal-regulated kinase （ERK） pathway inhibitor, PD98059, the Jun N-terminal kinase （JNK） pathway inhibitor, SP600125, and the p38 pathway inhibitor, SB203580, to investigate the roles of these pathways in HIV-1 replication. We found that application of PD98059 results in a strong VSV-G pseudotyped HIV-1NL4-3 luciferase reporter virus and HIV-1NL4-3 virus inhibition activity. In addition, SB203580 and SP600125 also elicited marked VSV-G pseudotyped HIV-INL4-3 luciferase reporter virus inhibition activity but no HIV-1NL4-3 virus inhibition activity. We also found that SB203580 and SP600125 can enhance the HIV-1 inhibition activity of PD98059 when cells were treated with all three MAPK pathway inhibitors in combination. Finally, we show that HIV-1 virus inhibition activity of the MAPK pathway inhibitors was the result of the negative regulation of HIV-1 LTR promoter activity.展开更多
Kidney fibrosis is an inevitable result of various chronic kidney diseases(CKDs)and significantly contributes to end-stage renal failure.Currently,there is no specific treatment available for renal fibrosis.ELA13(amin...Kidney fibrosis is an inevitable result of various chronic kidney diseases(CKDs)and significantly contributes to end-stage renal failure.Currently,there is no specific treatment available for renal fibrosis.ELA13(amino acid sequence:RRCMPLHSRVPFP)is a conserved region of ELABELA in all vertebrates;however,its biological activity has been very little studied.In the present study,we evaluated the therapeutic effect of ELA13 on transforming growth factor-β1(TGF-β1)-treated NRK-52E cells and unilateral ureteral occlusion(UUO)mice.Our results demonstrated that ELA13 could improve renal function by reducing creatinine and urea nitrogen content in serum,and reduce the expression of fibrosis biomarkers confirmed by Masson staining,immunohistochemistry,real-time polymerase chain reaction(RT-PCR),and western blot.Inflammation biomarkers were increased after UUO and decreased by administration of ELA13.Furthermore,we found that the levels of essential molecules in the mothers against decapentaplegic(Smad)and extracellular signal-regulated kinase(ERK)pathways were reduced by ELA13 treatment in vivo and in vitro.In conclusion,ELA13 protected against kidney fibrosis through inhibiting the Smad and ERK signaling pathways and could thus be a promising candidate for anti-renal fibrosis treatment.展开更多
Accumulating evidence indicates that endostatin inhibits fibrosis. However, the mechanism is yet to be clarified. The aim of this study is to evaluate the effect of endostatin on platelet-derived growth factor-BB （PD...Accumulating evidence indicates that endostatin inhibits fibrosis. However, the mechanism is yet to be clarified. The aim of this study is to evaluate the effect of endostatin on platelet-derived growth factor-BB （PDGF-BB）- or transforming growth factor β1 （TGF-β1）-induced fibrosis in cultured human skin fibroblasts, and to further examine the molecular mechanisms involved. Human dermal flbroblasts were cultured in Dulbecco＇s modified Eagle＇s medium （DMEM） and serum-starved for 48 h before treatment. Cells were grouped as follows： ＂PDGF-BB＂, ＂PDGF-BB＋ endostatin＂, ＂TGF-β1＂, ＂TGF-β1＋endostatin＂, ＂endostatin＂, and ＂blank control＂. The fibroblasts were stimulated with either TGF-β1 or PDGF-BB for 72 h in order to set up the fibrosis model in vitro. The cells were co-cultured with either TGF-β1 or PDGF-BB and endostatin and were used to check the inhibiting effect of endostatin. A blank control group and an endostatin group were used as negative control groups. The biomarkers of fibrosis, including the expression of collagen I, hydrroxyproline, and α-smooth muscle actin （a-SMA）, were evaluated using an enzyme-linked immune- sorbent assay （ELISA） and Western blot. The expression of phosphorylated PDGF receptor β （p-PDGFRβ）, PDGFRβ, phosphorylated extracellular signal-regulated kinase （p-ERK）, and ERK was detected using Western blot and im- munofiuorescent staining was used to explore the mechanisms. Both PDGF-BB and TGF-β1 significantly up-regulated the expression of collagen I, hydroxyproline, and a-SMA. Endostatin significantly attenuated both the PDGF-BB- and TGF-β1-induced over-expression of collagen I, hydroxyproline, and a-SMA. PDGF-BB and TGF-β1 both promoted the expression of PDGFR, ERK, and p-ERK. Endostatin inhibited the expression of PDGFR and p-ERK but did not affect the expression of total ERK. Endostatin inhibited hypertrophic scar by modulating the PDGFRI3/ERK pathway. En- dostatin could be a promising multi-target drug in future fibrosis therapy.展开更多
基金supported by the Medical and Healthcare Project of Zhejiang Province(No.2015119381),China
文摘Extracellular signal-regulated protein kinase 5 （ERK5）, also known as big mitogen-activated protein kinase 1 （MAPK1）, is an important member of ERK family, which is a subfamily of the large MAPK family. ERK5 is expressed in many tissues, including the dorsal root ganglion （DRG） neurons and the spinal cord. In this review, we focus on elaborating ERK5-associated pathway in pathological pain, in which the ERK5/CREB （cyclic adenosine monophos- phate （cAMP）-response element-binding protein） pathway plays a crucial role in the transduction of pain signal and contributes to pain hypersensitivity. ERK5 activation in the spinal dorsal horn occurs mainly in microglia. The activation of ERK5 can be mediated by N-methyI-D-aspartate （NMDA） receptors. We also elaborate the relationship between ERK5 activation and nerve growth factor-tyrosine kinase A （NGF-TrkA）, and the connection between ERK5 activation and brain-derived neurotrophic factor （BDNF） in pathological pain in detail.
基金supported by the National Natural Science Foundation of China (No. 30900654)the Science and Technology Department of Zhejiang Province (No. 2009R10031)the Health Bureau of Zhejiang Province (No. 2009QN010), China
文摘Objective： Mitogen-activated protein kinases （MAPKs） are correlated with a more malignant phenotype in many cancers. This study was designed to evaluate the predictive value of the expression of MAPK phosphatase-1 （MKP-1） and phosphorylated extracellular signal-regulated kinase 1/2 （p-ERKl/2）, as the key regulatory mechanism of the MAPKs, in lung squamous cell carcinoma （SCC）. Methods： We assessed the expressions of MKP-1 and p-ERK1/2 in twenty subjects at different differentiation degree of SCC and five normal lungs by immunohistochemistry and real-time reverse transcriptase polymerase chain reaction （RT-PCR） analysis. Results： Immunohistochemistry and real-time RT-PCR assay showed that the expression of MKP-1 was gradually decreased as tissue type went from normal lung tissues to increasingly undifferentiated carcinoma, and it was negatively correlated with tumor differentiation （P〈0.01）. However, the expression of p-ERK1/2 or ERKl/2 was gradually increased as tissue type went from normal lung tissues to increasingly undifferentiated carcinoma, and it was positively correlated with tumor differentiation （P〈0.01）. Conclusions： Our data indicates the relevance of MKP-1 and p-ERK1/2 in SCC as a potential positive and negative prognostic factor. The imbalanced expression of MKP-1 and p-ERKl/2 may play a role in the development of SCC and these two molecules may be new targets for the therapy and prognosis of SCC.
文摘Objective： To investigate the relationship between extracellular signal-regulated kinase （ERK） pathway, multidrug resistance gene （mdr-1）, ribonucleotide recluctase M1 （RRM1） gene and their roles in gemcitabine （GEM） chemoresistance in pancreatic cancer cell line SW1990. Methods： The GEM-resistance cell model was constructed by a stepwise method. Immunohistochemistry was used to measure the expression of ERK protein （ERK1/2） in the established cell strains in a semiquantitative way. The mRNA expression of mdr-1 and RRM1 were detected by RT-PCR. MTT assay was performed to determine the IC50 value. Results： The established GEM-resistant cell strains were able to gain stable growth and passage ability in the medium contained different concentration levels of GEM （0, 30, 60, 100, 150 and 200 nmol/L）. The expression of ERK protein, mdr-1 and RRM1 gene were elevated accompanied by the increase of GEM concentration. There was a highly positive correlation between mdr-1, RRM1 expression and GEM-resistanca level （r = 0.960, P = 0.002 and r = 0.966, P = 0.002）. The expression of ERK protein also correlated with the mdr-1 and RRM1 level （r = -0.943, P = 0.005 and r = -0.883, P = 0.02）. At the GEM-resistance level of 200 nmol/L, the grey scale value of ERK1/2 was 164.22 ±13.17, mdr-1/β-actin and RRM1/β-actin were 1.41 ±0.04 and 1.45 ± 0.18, respectively; after treated with ERK pathway inhibitor U0126, these values synchronously decreased to 186.85 ± 13.14, 0.2 3± 0.02 and 0.21 ± 0.03, respectively; inversely, the ERK1/2 grey scale value was 106.55 ± 16.45, mdr-l/β-actin and RRMl/β-actin were 1.50± 0.07 and 1.52 ± 0.12, respectively, which presented a tendency of synchronously increase after treated with ERK pathway activator EGF. The IC50 values in GEM-resistant cells of 0 nmol/L and 200 nmol/L levels were 4.104 and 10.20, respectively. After treated with U0126, these values decreased to 3.26 and 4.50, respectively; while treated with EGF, the IC50 values increased to 8.89 and 17.17, respectively. Conclusion： The ERK pathway may induce the GEM-chemoresistance in pancreatic cell line SW1990 through the participation in the regulation of the mdr-1 and RRM1 gene expression.
文摘Objective： To examine modulations caused by cyclooxygenase-2 （COX-2） inhibitors on altered microenvironments and overbalanced neurotransmitters in pilocarpine-induced epileptic status rats and to investigate possible mechanisms. Methods： Celecoxib （a COX-2 inhibitor） was administered 45 min prior to pilocarpine administration. The effects of COX-2 inhibitors on mlPSCs （miniature GABAergic inhibitory postsynaptic currents） of CA3 pyramidal cells in the hippocampus were recorded. Expressions of COX-2, c-Fos, newly generated neurons, and activated microgliosis were analyzed by immunohistochemistry, and expressions of c^-subunit of y-amino butyric acid （GABAA） receptors and mitogen-activated protein kinase/extracellular signal-regulated protein kinase （MAPK/ERK） activity were detected by Western blotting. Results： Pretreatment with celecoxib showed protection against pilocarpine-induced seizures. Celecoxib prevented microglia activation in the hilus and inhibited the abnormal neurogenesis and astrogliosis in the hippocampus by inhibiting MAPK/ERK activity and c-Fos transcription. Celecoxib also up-regulated the expression of GABAA receptors. NS-398 （N-2-cyclohexyloxy-4-nitrophenyl-methanesulfonamide）, another COX-2 inhibitor, enhanced the frequency and decay time of mIPSCs. Conclusion： The COX-2 inhibitor celecoxib decreased neuronal excitability and prevented epileptogenesis in pilocarpine-induced status epilepticus rats. Celecoxib regulates synaptic reorganization by inhibiting astrogliosis and ectopic neurogenesis by attenuating MAPK/ERK signal activity, mediated by a GABAergic mechanism.
基金supported by the Key Projects in the National Science and Technology Pillar Program during the Eleventh Five-Year Plan Period of China (2008ZX10001-002)Major Science and Technology Innovation Cross Project of the Chinese Academy of Sciences (KSCX1-YW-10)
文摘The human immunodeficiency virus type 1 （HIV-1） can interact with and exploit the host cellular machinery to replicate and propagate itself. Numerous studies have shown that the Mitogen-activated protein kinase （MAPK） signal pathway can positively regulate the replication of HIV-1, but exactly how each MAPK pathway affects HIV-1 infection and replication is not understood. In this study, we used the Extracellular signal-regulated kinase （ERK） pathway inhibitor, PD98059, the Jun N-terminal kinase （JNK） pathway inhibitor, SP600125, and the p38 pathway inhibitor, SB203580, to investigate the roles of these pathways in HIV-1 replication. We found that application of PD98059 results in a strong VSV-G pseudotyped HIV-1NL4-3 luciferase reporter virus and HIV-1NL4-3 virus inhibition activity. In addition, SB203580 and SP600125 also elicited marked VSV-G pseudotyped HIV-INL4-3 luciferase reporter virus inhibition activity but no HIV-1NL4-3 virus inhibition activity. We also found that SB203580 and SP600125 can enhance the HIV-1 inhibition activity of PD98059 when cells were treated with all three MAPK pathway inhibitors in combination. Finally, we show that HIV-1 virus inhibition activity of the MAPK pathway inhibitors was the result of the negative regulation of HIV-1 LTR promoter activity.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(No.LD22H310004)the National Natural Science Foundation of China(No.82204492)+2 种基金the CAMS Innovation Fund for Medical Sciences(CIFMS)(No.2019-I2M-5-074)the Medical Innovation and Development Project of Lanzhou University(No.lzuyxcx-2022-156)the Scientific Research Foundation of Zhejiang Sci-Tech University(No.21042100-Y),China。
文摘Kidney fibrosis is an inevitable result of various chronic kidney diseases(CKDs)and significantly contributes to end-stage renal failure.Currently,there is no specific treatment available for renal fibrosis.ELA13(amino acid sequence:RRCMPLHSRVPFP)is a conserved region of ELABELA in all vertebrates;however,its biological activity has been very little studied.In the present study,we evaluated the therapeutic effect of ELA13 on transforming growth factor-β1(TGF-β1)-treated NRK-52E cells and unilateral ureteral occlusion(UUO)mice.Our results demonstrated that ELA13 could improve renal function by reducing creatinine and urea nitrogen content in serum,and reduce the expression of fibrosis biomarkers confirmed by Masson staining,immunohistochemistry,real-time polymerase chain reaction(RT-PCR),and western blot.Inflammation biomarkers were increased after UUO and decreased by administration of ELA13.Furthermore,we found that the levels of essential molecules in the mothers against decapentaplegic(Smad)and extracellular signal-regulated kinase(ERK)pathways were reduced by ELA13 treatment in vivo and in vitro.In conclusion,ELA13 protected against kidney fibrosis through inhibiting the Smad and ERK signaling pathways and could thus be a promising candidate for anti-renal fibrosis treatment.
基金Project supported by the Zhejiang Provincial Natural Science Foundation of China(No.LY15H150004)the Teaching Department of the Zhejiang Province(No.Y201330073),China
文摘Accumulating evidence indicates that endostatin inhibits fibrosis. However, the mechanism is yet to be clarified. The aim of this study is to evaluate the effect of endostatin on platelet-derived growth factor-BB （PDGF-BB）- or transforming growth factor β1 （TGF-β1）-induced fibrosis in cultured human skin fibroblasts, and to further examine the molecular mechanisms involved. Human dermal flbroblasts were cultured in Dulbecco＇s modified Eagle＇s medium （DMEM） and serum-starved for 48 h before treatment. Cells were grouped as follows： ＂PDGF-BB＂, ＂PDGF-BB＋ endostatin＂, ＂TGF-β1＂, ＂TGF-β1＋endostatin＂, ＂endostatin＂, and ＂blank control＂. The fibroblasts were stimulated with either TGF-β1 or PDGF-BB for 72 h in order to set up the fibrosis model in vitro. The cells were co-cultured with either TGF-β1 or PDGF-BB and endostatin and were used to check the inhibiting effect of endostatin. A blank control group and an endostatin group were used as negative control groups. The biomarkers of fibrosis, including the expression of collagen I, hydrroxyproline, and α-smooth muscle actin （a-SMA）, were evaluated using an enzyme-linked immune- sorbent assay （ELISA） and Western blot. The expression of phosphorylated PDGF receptor β （p-PDGFRβ）, PDGFRβ, phosphorylated extracellular signal-regulated kinase （p-ERK）, and ERK was detected using Western blot and im- munofiuorescent staining was used to explore the mechanisms. Both PDGF-BB and TGF-β1 significantly up-regulated the expression of collagen I, hydroxyproline, and a-SMA. Endostatin significantly attenuated both the PDGF-BB- and TGF-β1-induced over-expression of collagen I, hydroxyproline, and a-SMA. PDGF-BB and TGF-β1 both promoted the expression of PDGFR, ERK, and p-ERK. Endostatin inhibited the expression of PDGFR and p-ERK but did not affect the expression of total ERK. Endostatin inhibited hypertrophic scar by modulating the PDGFRI3/ERK pathway. En- dostatin could be a promising multi-target drug in future fibrosis therapy.
