Objective： The aim of our study was to investigate the effects of （-）-epigallocatechin-3-gallate （EGCG, the major phytochemistry component in green tea） on the expression of connexin43 （Cx43） gene and detect th...Objective： The aim of our study was to investigate the effects of （-）-epigallocatechin-3-gallate （EGCG, the major phytochemistry component in green tea） on the expression of connexin43 （Cx43） gene and detect the intercellular communication of the human bladder cancer cell lines BIU-87, and explore its possible mechanisms of prevention and cure for the bladder tumor. Methods： The methyl thiazolyl tetrazolium and Annexin-V/PI double-labeled flow cytometry methods were used to observe the growth inhibitory rate （IR） and apoptosis rate （AR） of BlU-87 cells treated by EGCG at different concentrations （0, 5, 10 and 20 mg/L）, respectively. The reverse transcription-polymerase chain reaction （RT-PCR） and Western Blotting analysis were employed to detect the relative expression levels of the Cx43 mRNA and its protein. The scrape-loading fluorescence dye transfer method was used to assess the gap junction intercellular communication （GJIC） under fluorescence microscope. Results： EGCG at concentrations （10 and 20 mg/L） both could significantly inhibit the proliferation and induce the apoptosis of BIU-87 cells. The IR and AR were （15.67 ± 1.15）%, （18.33 ± 1.53）% and （42.00 ± 4.34）%, （27.33 ± 3.21）%, respectively. And compared with the control groups of 0 mg/L and 5 mg/L （P 〈 0.05）, EGCG could significantly up-regulate the expression of Cx43 mRNA and its protein and enhance the function of BIU-87 cells. The effects had the significant correlation with the dose-dependent of EGCG. Conclusion： EGCG （10, 20 mg/L） could effectively up-regulate Cx43 expression and enhance the GJIC of BlU-87 cells. The results may indicate the effects of EGCG inducing bladder tumor cells apoptosis and inhibiting its growth which provides the experimental evidence for further demonstrating the mechanism of chemical prevention and cure for the bladder tumor by EGCG.展开更多
Epilepsy is a common neurological disorder characterized by periodic and unpredictable seizures.Gap junctions have recently been proposed to be involved in the generation,synchronization and maintenance of seizure eve...Epilepsy is a common neurological disorder characterized by periodic and unpredictable seizures.Gap junctions have recently been proposed to be involved in the generation,synchronization and maintenance of seizure events.The present review mainly summarizes recent reports concerning the contribution of gap junctions to the pathophysiology of epilepsy,together with the regulation of connexin after clinical and experimental seizure activity.The anticonvulsant effects of gap junction blockers both in vitro and in vivo suggest that the gap junction is a candidate target for the development of antiepileptic drugs.It is also of interest that the roles of neuronal and astrocytic gap junctions in epilepsy have been investigated independently,based on evidence from pharmacological manipulations and connexin-knockout mice.Further studies using more specific manipulations of gap junctions in different cell types and in human epileptic tissue are needed to fully uncover the role of gap junctions in epilepsy.展开更多
基金Supported by a grant from the National Natural Sciences Foundation of China(No.30801138)
文摘Objective： The aim of our study was to investigate the effects of （-）-epigallocatechin-3-gallate （EGCG, the major phytochemistry component in green tea） on the expression of connexin43 （Cx43） gene and detect the intercellular communication of the human bladder cancer cell lines BIU-87, and explore its possible mechanisms of prevention and cure for the bladder tumor. Methods： The methyl thiazolyl tetrazolium and Annexin-V/PI double-labeled flow cytometry methods were used to observe the growth inhibitory rate （IR） and apoptosis rate （AR） of BlU-87 cells treated by EGCG at different concentrations （0, 5, 10 and 20 mg/L）, respectively. The reverse transcription-polymerase chain reaction （RT-PCR） and Western Blotting analysis were employed to detect the relative expression levels of the Cx43 mRNA and its protein. The scrape-loading fluorescence dye transfer method was used to assess the gap junction intercellular communication （GJIC） under fluorescence microscope. Results： EGCG at concentrations （10 and 20 mg/L） both could significantly inhibit the proliferation and induce the apoptosis of BIU-87 cells. The IR and AR were （15.67 ± 1.15）%, （18.33 ± 1.53）% and （42.00 ± 4.34）%, （27.33 ± 3.21）%, respectively. And compared with the control groups of 0 mg/L and 5 mg/L （P 〈 0.05）, EGCG could significantly up-regulate the expression of Cx43 mRNA and its protein and enhance the function of BIU-87 cells. The effects had the significant correlation with the dose-dependent of EGCG. Conclusion： EGCG （10, 20 mg/L） could effectively up-regulate Cx43 expression and enhance the GJIC of BlU-87 cells. The results may indicate the effects of EGCG inducing bladder tumor cells apoptosis and inhibiting its growth which provides the experimental evidence for further demonstrating the mechanism of chemical prevention and cure for the bladder tumor by EGCG.
基金supported by the National Basic Research Development Program (973 Program) of China (2011CB504403)the National Natural Science Foundation of China (81030061,30725047,and 30801392)
文摘Epilepsy is a common neurological disorder characterized by periodic and unpredictable seizures.Gap junctions have recently been proposed to be involved in the generation,synchronization and maintenance of seizure events.The present review mainly summarizes recent reports concerning the contribution of gap junctions to the pathophysiology of epilepsy,together with the regulation of connexin after clinical and experimental seizure activity.The anticonvulsant effects of gap junction blockers both in vitro and in vivo suggest that the gap junction is a candidate target for the development of antiepileptic drugs.It is also of interest that the roles of neuronal and astrocytic gap junctions in epilepsy have been investigated independently,based on evidence from pharmacological manipulations and connexin-knockout mice.Further studies using more specific manipulations of gap junctions in different cell types and in human epileptic tissue are needed to fully uncover the role of gap junctions in epilepsy.
