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Objective To investigate the role of mitochondrial respiratory chain (MRC) in induction of reactive oxygen species (ROS) by hyperbaric oxygen (HBO).Methods Superoxide anion (O·-2) specific fluorescence probe DHE and mitochondrial O·-2 probe Mito-SOX were used to label ROS in human umbilical vein endothelium cells(HUVEC) microscopically after HBO exposure.Results After HBO exposure, O·-2 increased (31±8)% and (137±19) % in whole cells and in mitochondria, respectively (P<0.01).These increments were suppressed by MRC complex Ⅱ inhibitor TTFA for (55±11)% in whole cells (P<0.05)and (61±8) % in mitochondria(P<0.01).Conclusion MRC may be the main source of ROS induced by HBO in HUVECs.
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Aim To investigate the role of captopril in insulin resistance of endothelial cells induced by high glucose.Methods 1 .Improvement effect of captopril on insulin resistance in HUVECs was observed.The HUVECs were seeded in a 6-well plate and were ran-domly divided into 5 groups,namely,control group, IR group,IR together with different Cap concentrations (low,medium and high concentration),respectively. 2.Improvement effect of Cap on insulin resistance was mediated by PPARγin HUVECs.HUVECs were ran-domly divided into 6 groups,namely,control group, control +PPARγinhibitor (PI)(1 .0 μmol · L -1 ) group,IR group,IR +PI(1 .0 μmol·L -1 )group,IR +Cap(1 ×1 0 -5 mol·L -1 ) group,and IR +Cap +PI (1 .0 μmol·L -1 )group.All indicators were detected. Results After HUVECs were incubated with media containing 33 mmol·L -1 of glucose for 48 h,the NO levels were significantly decreased while ET-1 levels were significantly elevated,showing a significant differ-ence between IR group and control group (P 0.05).When the HUVECs in IR group were treated with DMEM containing glucose (33 mmol·L -1 )for 48 h and insulin for 30 min,the expression levels of PPARγmRNA and its protein in Cap groups were simi-lar to those in the IR group,and there was no signifi-cant difference between the two groups (P >0.05 );however, the expression levels of phosphorylated PPARγprotein in Cap groups were increased compared with IR group (P <0.05).The levels of NO were sig-nificantly increased whereas the levels of ET-1 were decreased in Cap groups,which had significant differ-ences compared with IR group (P <0.05).Nonethe-less,pre-treating with GW9662,a PPARγinhibitor, the improvement effects of Cap were markedly abol-ished.Conclusions Captopril could improve high glucose-induced insulin resistance of endothelial cells mediated by PPARγ,and the underlying mechanisms are related to the activation of PPARγ,rather than its expression.
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Objective To investigate the effect of pronuciferine on apoptosis of cultured human umbilical vein endothelium cells(HUVECs) induced by angiotensin Ⅱ(AngⅡ).Methods HUVECs cell line ECV304 was cultured in vitro,pretreated with Captopril(10 ?mol/L) or pronuciferine 10,1,0.1,0.01 ?mol/L for 30 min,respectively,then treated with AngⅡ(1 ?mol/L).Cell-morphosis was observed by light microscope.Cells viability was assessed by MTT assay.Production of nitric oxide(NO),activities of total nitric oxide synthase(tNOS),and inducible nitric oxide synthase(iNOS) were measured by colorimetry.Apoptosis rate was measured by Flow Cytometer(FCM).Results AngⅡ induced typical endothelial cell apoptosis and the apoptosis rates were significantly higher than those of the control group((P