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
Molecular interactions are the key to understanding the structure and properties of materials. Also, it is critical of chiral recognition. Since the molecular interactions at play in chiral discrimination is difficult...Molecular interactions are the key to understanding the structure and properties of materials. Also, it is critical of chiral recognition. Since the molecular interactions at play in chiral discrimination is difficult to investigate under traditional experiment conditions. We have undertaken a computer experiment of van der Waals interaction between chiral molecules and a polymer, which works for chiral separation. Building molecular models, choosing proper force field and Monte Carlo method, we have calculated the difference of interaction energy between isotactic poly (triphenylmethyl methacrylate) and (+) hexahelicene or (-) hexahelicene. It is finally found about 1.379 4 kJ/mol between the polymer and the two chiral hexahelicenes. Reasonably, this difference is regardd as the main reason which induced chiral separation. Furthermore, we compared the results from computer smulation with that from experiment. It can be seen that some details during chiral separation process, such as trailing effect, can also be predicted, and be consistent with the experiment results. Finally, the effective structureal characteristics of the recognition site are pointed out.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.
文摘Molecular interactions are the key to understanding the structure and properties of materials. Also, it is critical of chiral recognition. Since the molecular interactions at play in chiral discrimination is difficult to investigate under traditional experiment conditions. We have undertaken a computer experiment of van der Waals interaction between chiral molecules and a polymer, which works for chiral separation. Building molecular models, choosing proper force field and Monte Carlo method, we have calculated the difference of interaction energy between isotactic poly (triphenylmethyl methacrylate) and (+) hexahelicene or (-) hexahelicene. It is finally found about 1.379 4 kJ/mol between the polymer and the two chiral hexahelicenes. Reasonably, this difference is regardd as the main reason which induced chiral separation. Furthermore, we compared the results from computer smulation with that from experiment. It can be seen that some details during chiral separation process, such as trailing effect, can also be predicted, and be consistent with the experiment results. Finally, the effective structureal characteristics of the recognition site are pointed out.