The present study was designed to determine the effects of Guanfu base A(GFA) on the late sodium current(INa.L),transient sodium current(INa.T),HERG current(IHERG),and Kv1.5 current(IKv1.5).The values of INa.L,INa.T,I...The present study was designed to determine the effects of Guanfu base A(GFA) on the late sodium current(INa.L),transient sodium current(INa.T),HERG current(IHERG),and Kv1.5 current(IKv1.5).The values of INa.L,INa.T,IHERG and IKv1.5 were recorded using the whole-cell patch clamp technique.Compared with other channels,GFA showed selective blocking activity in late sodium channel.It inhibited INa.L in a concentration-dependent manner with an IC50 of(1.57 ± 0.14) μmol·L-1,which was significantly lower than its IC50 values of(21.17 ± 4.51) μmol·L-1 for the INa.T.The inhibitory effect of GFA on INa,L was not affected by 200μmol·L-1 H2O2.It inhibited IHERG with an IC50 of(273 ± 34) μmol·L-1 and has slight blocking effect on IKv1.5,decreasing IKv1.5 by only 20.6% at 200 μmol·L-1.In summary,GFA inhibited INa.L selectively and remained similar inhibition in presence of reactive oxygen species..These findings may suggest a novel molecular mechanism for the potential clinical application of GFA in the treatment of cardiovascular disorders.展开更多
Background: Voltage-gated sodium channel 1.5(Nav1.5) potentially promotes the migratory and invasive behaviors of colon cancer cells. Hitherto, the prognostic significance of Nav1.5 expression remains undetermined. Th...Background: Voltage-gated sodium channel 1.5(Nav1.5) potentially promotes the migratory and invasive behaviors of colon cancer cells. Hitherto, the prognostic significance of Nav1.5 expression remains undetermined. The present study aimed to explore the associations of Nav1.5 expression with clinical outcomes and estrogen receptor-β(ER-β)expression in non-metastatic colon cancer patients receiving radical resection.Methods: A total of 269 consecutive patients with pathologically confirmed stages Ⅰ-Ⅲ colon cancer who underwent radical resection were selected. Nav1.5 and ER-β expression was detected by using immunohistochemistry(IHC)on tissue microarray constructed from paraffin-embedded specimens. IHC score was determined according to the percentage and intensity of positively stained cells. Statistical analysis was performed with the X-tile method, k coefficient, Chi square test or Fisher's exact test, logistic regression, log-rank test, and Cox proportional hazards models.Results: We found that Nav1.5 was commonly expressed in tumor tissues with higher mean IHC score as compared with matched tumor-adjacent normal tissues(5.1 ± 3.5 vs. 3.5 ± 2.7, P < 0.001).The high expression of Nav1.5 in colon cancer tissues was associated with high preoperative carcinoembryonic antigen level [odds ratio(OR) = 2.980;95% confidential interval(CI)1.163-7.632; P = 0.023] and high ER-β expression(OR = 2.808; 95% CI 1.243-6.343;p = 0.00 3). Log-rank test results showed that high Nav1.5 expression contributed to a low 5-year disease-free survival(DFS) rate in colon cancer patients(77.2% vs. 92.1%, P = 0.048), especially in patients with high ER-β expression tumor(76.2% vs. 91.3%, P = 0.032). Analysis with Cox proportional hazards model demonstrated that high Nav1.5 expression[hazard ratio(HR) = 2.738; 95% CI 1.100-6.819;P = 0.030] and lymph node metastasis(HR = 2.633; 95% CI 1.632-4.248; P < 0.001) were prognostic factors for unfavorable DFS in colon cancer patients.Conclusions: High expression of Nav1.5 was associated with high expression of ER-β and indicated unfavorable oncologic prognosis in patients with non-metastatic colon cancer.展开更多
Voltage-gated sodium channels （VGSCs） are known to be involved in the initiation and progression of many malignancies, and the different subtypes of VGSCs play important roles in the metastasis cascade of many tumor...Voltage-gated sodium channels （VGSCs） are known to be involved in the initiation and progression of many malignancies, and the different subtypes of VGSCs play important roles in the metastasis cascade of many tumors. This study investigated the functional expression of Nav1.5 and its effect on invasion behavior of human breast cancer cell line MDA-MB-231. The mRNA and protein expression of Nav1.5 was detected by real time PCR, Western Blot and immunofluorescence. The effects of Nav1.5 on cell proliferation, migration and invasion were respectively assessed by MTT and Transwell. The effects of Nav1.5 on the secretion of matrix metalloproteases （MMPs） by MDA-MB-231 were analyzed by RT-PCR. The over-expressed Nav 1.5 was present on the membrane of MDA-MB-231 cells. The invasion ability in vitro and the MMP-9 mRNA expression were respectively decreased to （47.82±0.53）% and （43.97±0.64）% （P〈0.05） respectively in MDA-MB-23 t cells treated with VGSCs specific inhibitor tetrodotoxin （TTX） by blocking Navl.5 activity. It was concluded that Navl.5 functional expression potentiated the invasive behavior of human breast cancer cell line MDA-MB-231 by increasing the secretion of MMP-9.展开更多
Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system diseases.The neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may de...Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system diseases.The neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may depend on the pathological process and cell types involved.Voltage-gated sodium channels(VGSCs)are essential ion channels for the generation of action potentials in neurons,and are involved in various neuroexcitation-related diseases.However,the effects of TGF-β1 on the functional properties of VGSCs and firing properties in cortical neurons remain unclear.In this study,we investigated the effects of TGF-β1 on VGSC function and firing properties in primary cortical neurons from mice.We found that TGF-β1 increased VGSC current density in a dose-and time-dependent manner,which was attributable to the upregulation of Nav1.3 expression.Increased VGSC current density and Nav1.3 expression were significantly abolished by preincubation with inhibitors of mitogen-activated protein kinase kinase(PD98059),p38 mitogen-activated protein kinase(SB203580),and Jun NH2-terminal kinase 1/2 inhibitor(SP600125).Interestingly,TGF-β1 significantly increased the firing threshold of action potentials but did not change their firing rate in cortical neurons.These findings suggest that TGF-β1 can increase Nav1.3 expression through activation of the ERK1/2-JNK-MAPK pathway,which leads to a decrease in the firing threshold of action potentials in cortical neurons under pathological conditions.Thus,this contributes to the occurrence and progression of neuroexcitatory-related diseases of the central nervous system.展开更多
基金supported by the Fundamental Research Funds for the Central Universities(No.JKZ2011007)the National "Key Program for New Drug Research Development"(No.2009 ZX09103-345)
文摘The present study was designed to determine the effects of Guanfu base A(GFA) on the late sodium current(INa.L),transient sodium current(INa.T),HERG current(IHERG),and Kv1.5 current(IKv1.5).The values of INa.L,INa.T,IHERG and IKv1.5 were recorded using the whole-cell patch clamp technique.Compared with other channels,GFA showed selective blocking activity in late sodium channel.It inhibited INa.L in a concentration-dependent manner with an IC50 of(1.57 ± 0.14) μmol·L-1,which was significantly lower than its IC50 values of(21.17 ± 4.51) μmol·L-1 for the INa.T.The inhibitory effect of GFA on INa,L was not affected by 200μmol·L-1 H2O2.It inhibited IHERG with an IC50 of(273 ± 34) μmol·L-1 and has slight blocking effect on IKv1.5,decreasing IKv1.5 by only 20.6% at 200 μmol·L-1.In summary,GFA inhibited INa.L selectively and remained similar inhibition in presence of reactive oxygen species..These findings may suggest a novel molecular mechanism for the potential clinical application of GFA in the treatment of cardiovascular disorders.
基金supported by a grant from the Sun Yat-sen University Clinical Research 5010 Program(Grant No.2015024)a grant of Guangzhou Science and Technology Plan Projects(Health Medical Collaborative Innovation Program of Guangzhou)(Grant No.201400000001-4)a grant of National Natural Science Foundation of China(Grant No.81772595)
文摘Background: Voltage-gated sodium channel 1.5(Nav1.5) potentially promotes the migratory and invasive behaviors of colon cancer cells. Hitherto, the prognostic significance of Nav1.5 expression remains undetermined. The present study aimed to explore the associations of Nav1.5 expression with clinical outcomes and estrogen receptor-β(ER-β)expression in non-metastatic colon cancer patients receiving radical resection.Methods: A total of 269 consecutive patients with pathologically confirmed stages Ⅰ-Ⅲ colon cancer who underwent radical resection were selected. Nav1.5 and ER-β expression was detected by using immunohistochemistry(IHC)on tissue microarray constructed from paraffin-embedded specimens. IHC score was determined according to the percentage and intensity of positively stained cells. Statistical analysis was performed with the X-tile method, k coefficient, Chi square test or Fisher's exact test, logistic regression, log-rank test, and Cox proportional hazards models.Results: We found that Nav1.5 was commonly expressed in tumor tissues with higher mean IHC score as compared with matched tumor-adjacent normal tissues(5.1 ± 3.5 vs. 3.5 ± 2.7, P < 0.001).The high expression of Nav1.5 in colon cancer tissues was associated with high preoperative carcinoembryonic antigen level [odds ratio(OR) = 2.980;95% confidential interval(CI)1.163-7.632; P = 0.023] and high ER-β expression(OR = 2.808; 95% CI 1.243-6.343;p = 0.00 3). Log-rank test results showed that high Nav1.5 expression contributed to a low 5-year disease-free survival(DFS) rate in colon cancer patients(77.2% vs. 92.1%, P = 0.048), especially in patients with high ER-β expression tumor(76.2% vs. 91.3%, P = 0.032). Analysis with Cox proportional hazards model demonstrated that high Nav1.5 expression[hazard ratio(HR) = 2.738; 95% CI 1.100-6.819;P = 0.030] and lymph node metastasis(HR = 2.633; 95% CI 1.632-4.248; P < 0.001) were prognostic factors for unfavorable DFS in colon cancer patients.Conclusions: High expression of Nav1.5 was associated with high expression of ER-β and indicated unfavorable oncologic prognosis in patients with non-metastatic colon cancer.
文摘Voltage-gated sodium channels （VGSCs） are known to be involved in the initiation and progression of many malignancies, and the different subtypes of VGSCs play important roles in the metastasis cascade of many tumors. This study investigated the functional expression of Nav1.5 and its effect on invasion behavior of human breast cancer cell line MDA-MB-231. The mRNA and protein expression of Nav1.5 was detected by real time PCR, Western Blot and immunofluorescence. The effects of Nav1.5 on cell proliferation, migration and invasion were respectively assessed by MTT and Transwell. The effects of Nav1.5 on the secretion of matrix metalloproteases （MMPs） by MDA-MB-231 were analyzed by RT-PCR. The over-expressed Nav 1.5 was present on the membrane of MDA-MB-231 cells. The invasion ability in vitro and the MMP-9 mRNA expression were respectively decreased to （47.82±0.53）% and （43.97±0.64）% （P〈0.05） respectively in MDA-MB-23 t cells treated with VGSCs specific inhibitor tetrodotoxin （TTX） by blocking Navl.5 activity. It was concluded that Navl.5 functional expression potentiated the invasive behavior of human breast cancer cell line MDA-MB-231 by increasing the secretion of MMP-9.
基金supported by the Natural Science Foundation of Guangdong Province,Nos.2019A1515010649(to WC),2022A1515012044(to JS)the China Postdoctoral Science Foundation,No.2018M633091(to JS).
文摘Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system diseases.The neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may depend on the pathological process and cell types involved.Voltage-gated sodium channels(VGSCs)are essential ion channels for the generation of action potentials in neurons,and are involved in various neuroexcitation-related diseases.However,the effects of TGF-β1 on the functional properties of VGSCs and firing properties in cortical neurons remain unclear.In this study,we investigated the effects of TGF-β1 on VGSC function and firing properties in primary cortical neurons from mice.We found that TGF-β1 increased VGSC current density in a dose-and time-dependent manner,which was attributable to the upregulation of Nav1.3 expression.Increased VGSC current density and Nav1.3 expression were significantly abolished by preincubation with inhibitors of mitogen-activated protein kinase kinase(PD98059),p38 mitogen-activated protein kinase(SB203580),and Jun NH2-terminal kinase 1/2 inhibitor(SP600125).Interestingly,TGF-β1 significantly increased the firing threshold of action potentials but did not change their firing rate in cortical neurons.These findings suggest that TGF-β1 can increase Nav1.3 expression through activation of the ERK1/2-JNK-MAPK pathway,which leads to a decrease in the firing threshold of action potentials in cortical neurons under pathological conditions.Thus,this contributes to the occurrence and progression of neuroexcitatory-related diseases of the central nervous system.
