AIM:To explore the influence of ethyl(2,4,6-trimethylbenzoyl)phenylphosphinate(TPOL)on cell apoptosis and its potential mechanism.METHODS:HEK293T cells sensitive to TPOL were treated with different concentrations of T...AIM:To explore the influence of ethyl(2,4,6-trimethylbenzoyl)phenylphosphinate(TPOL)on cell apoptosis and its potential mechanism.METHODS:HEK293T cells sensitive to TPOL were treated with different concentrations of TPOL with or without exposure to light radiation,before treatment with various inhibitors,N-acetyl-Lcysteine(NAC),pifithrin-αand Z-DVED-FMK.Cell viability was measured by CCK-8 assay.Annexin V/propidium iodide staining was used to count the number of apoptotic cells.DCFH-DA staining was used to detect reactive oxygen species(ROS)levels,and JC-1 staining was used to assess mitochondrial membrane potential by flow cytometry.The expression of apoptosis-related proteins and cell cycle-regulated molecules was measured by Western blot.RESULTS:TPOL enhanced the apoptosis of HEK293T cells in a dose-dependent manner(P<0.05),with a decrease in Bcl-2 and increases in Bax and cytochrome C(Cyto C),followed by up-regulation of activated caspase-9 and caspase-3,and the cleavage of PARP(P<0.05).The TPOL-enhanced cleavage of caspase-3 and PARP was rescued by Z-DVED-FMK(P<0.01).TPOL also led to a rapid increase in ROS,a reduction in mitochondrial membrane potential,and the release of Cyto C(P<0.01),all of which could be reversed by the ROS scavenger NAC.Moreover,the TPOL-caused alterations in p21,p27,Rb,and CDK2 were also recovered by the p53 inhibitor pifithrin-α(P<0.05).The TPOL-induced changes in Bax,Bcl-2,cleaved caspase-9,activated caspase-3,and cleaved PARP were subsequently rescued by pretreatment with pifithrin-α(P<0.05).CONCLUSION:TPOL can induce cellular apoptosis with ROS-mediated mitochondrial membrane damage through the activation of a ROS-dependent p53/p21/p27/Rb/Bax/Cyto C/caspase-mediated signal axis.展开更多
A soluble Jagged 1/Fc chimera protein (Jagged 1/Fc) was directly used to induce differentiation and maturation of bone marrow-derived dendritic cells (DCs) in mice in vitro. A model of inducing and am-plifying DCs in ...A soluble Jagged 1/Fc chimera protein (Jagged 1/Fc) was directly used to induce differentiation and maturation of bone marrow-derived dendritic cells (DCs) in mice in vitro. A model of inducing and am-plifying DCs in vitro was established. The effect of Jagged 1/Fc on morphology of DCs induced by both rmGM-CSF and rmIL-4 was observed under a confocal microscope. A fluorescein-labeled monoclonal antibody staining combined with flow cytometry was applied to detect the effect of Jagged 1/Fc on the expression of CD11c, MHC-II, CD86, CD80 and CD40 molecules on the surface of DCs. The results showed that Jagged 1/Fc did not affect the morphological properties of DC differentiation induced by both rmGM-CSF and rmIL-4. But it could promote the differentiation and maturation of DCs induced by both. The effect of it was strikingly different in the expression profile of co-stimulating molecules and the morphologic properties of DCs from lipopolysaccharide (LPS). The levels of MHC-II and CD40 molecule expression on the surface of DCs stimulated by Jagged 1/Fc were significantly lower than those stimulated by LPS, and the level of CD80 expression on the surface of DCs induced by Jagged 1/Fc was near to that induced by LPS. Jagged 1/Fc had no influence on the expression of CD86 mole-cule on the surface of DCs. Jagged 1/Fc when used alone could not maintain the growth, differentiation and maturation of DCs. All the findings indicate that Jagged 1/Fc influences the differentiation and maturation of DCs, which is not markedly similar to LPS, providing important evidence for its devel-opment and application as a novel immunosuppressant.展开更多
基金Supported by the National Natural Science Foundation of China(No.81172824)。
文摘AIM:To explore the influence of ethyl(2,4,6-trimethylbenzoyl)phenylphosphinate(TPOL)on cell apoptosis and its potential mechanism.METHODS:HEK293T cells sensitive to TPOL were treated with different concentrations of TPOL with or without exposure to light radiation,before treatment with various inhibitors,N-acetyl-Lcysteine(NAC),pifithrin-αand Z-DVED-FMK.Cell viability was measured by CCK-8 assay.Annexin V/propidium iodide staining was used to count the number of apoptotic cells.DCFH-DA staining was used to detect reactive oxygen species(ROS)levels,and JC-1 staining was used to assess mitochondrial membrane potential by flow cytometry.The expression of apoptosis-related proteins and cell cycle-regulated molecules was measured by Western blot.RESULTS:TPOL enhanced the apoptosis of HEK293T cells in a dose-dependent manner(P<0.05),with a decrease in Bcl-2 and increases in Bax and cytochrome C(Cyto C),followed by up-regulation of activated caspase-9 and caspase-3,and the cleavage of PARP(P<0.05).The TPOL-enhanced cleavage of caspase-3 and PARP was rescued by Z-DVED-FMK(P<0.01).TPOL also led to a rapid increase in ROS,a reduction in mitochondrial membrane potential,and the release of Cyto C(P<0.01),all of which could be reversed by the ROS scavenger NAC.Moreover,the TPOL-caused alterations in p21,p27,Rb,and CDK2 were also recovered by the p53 inhibitor pifithrin-α(P<0.05).The TPOL-induced changes in Bax,Bcl-2,cleaved caspase-9,activated caspase-3,and cleaved PARP were subsequently rescued by pretreatment with pifithrin-α(P<0.05).CONCLUSION:TPOL can induce cellular apoptosis with ROS-mediated mitochondrial membrane damage through the activation of a ROS-dependent p53/p21/p27/Rb/Bax/Cyto C/caspase-mediated signal axis.
基金the National Natural Science Foundation of China (Grant No. 30471635)the Natural Science Foundation of Guangdong Province (Grant Nos. 04010451 and 5006033)
文摘A soluble Jagged 1/Fc chimera protein (Jagged 1/Fc) was directly used to induce differentiation and maturation of bone marrow-derived dendritic cells (DCs) in mice in vitro. A model of inducing and am-plifying DCs in vitro was established. The effect of Jagged 1/Fc on morphology of DCs induced by both rmGM-CSF and rmIL-4 was observed under a confocal microscope. A fluorescein-labeled monoclonal antibody staining combined with flow cytometry was applied to detect the effect of Jagged 1/Fc on the expression of CD11c, MHC-II, CD86, CD80 and CD40 molecules on the surface of DCs. The results showed that Jagged 1/Fc did not affect the morphological properties of DC differentiation induced by both rmGM-CSF and rmIL-4. But it could promote the differentiation and maturation of DCs induced by both. The effect of it was strikingly different in the expression profile of co-stimulating molecules and the morphologic properties of DCs from lipopolysaccharide (LPS). The levels of MHC-II and CD40 molecule expression on the surface of DCs stimulated by Jagged 1/Fc were significantly lower than those stimulated by LPS, and the level of CD80 expression on the surface of DCs induced by Jagged 1/Fc was near to that induced by LPS. Jagged 1/Fc had no influence on the expression of CD86 mole-cule on the surface of DCs. Jagged 1/Fc when used alone could not maintain the growth, differentiation and maturation of DCs. All the findings indicate that Jagged 1/Fc influences the differentiation and maturation of DCs, which is not markedly similar to LPS, providing important evidence for its devel-opment and application as a novel immunosuppressant.
