Correlation between NADPH oxidase-mediated oxidative stress and dysfunction of endothelial progenitor cell in hyperlipidemic patients

BACKGROUND/AIMS: NADPH (nicotinamide adenine dinucleotide phosphate) oxidase (NOX)-mediated oxidative stress plays a key role in promotion of oxidative injury in the cardiovascular system. The aim of this study is to evaluate the status of NOX in endothelial progenitor cells (EPCs) of hyperlipidemic patients and to assess the correlation between NOX activity and the functions EPCs. METHODS: A total of 30 hyperlipidemic patients were enrolled for this study and 30 age-matched volunteers with normal level of plasma lipids served as controls. After the circulating EPCs were isolated, the EPC functions (migration, adhesion and tube formation) were evaluated and the status of NOX (expression and activity) was examined. RESULTS: Compared to the controls, hyperlipidemic patients showed an increase in plasma lipids and a reduction in EPC functions including the attenuated abilities in adhesion, migration and tube formation, concomitant with an increase in NOX expression (NOX2 and NOX4), NOX activity, and reactive oxygen species production. The data analysis showed negative correlations between NOX activity and EPC functions. CONCLUSIONS: There is a positive correlation between the NOX-mediated oxidative stress and the dysfunctions of circulating EPCs in hyperlipidemic patients, and suppression of NOX might offer a novel strategy to improve EPCs functions in hyperlipidemia.

NADPH oxidase inhibitor apocynin attenuates ischemia/reperfusion induced myocardial injury in rats / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore the role of NADPH oxidase inhibitor apocynin on ischemia/reperfusion (I/R)-induced myocardial injury.</p><p><b>METHODS</b>Male SD rat hearts were divided into the normal control group; sham group; I/R group (1 h ischemia followed by 3 h reperfusion); I/R + apocynin group (50 mg/kg, administrated at 30 min before reperfusion) and I/R + vehicle group (same volume vehicle administrated at 30 min before reperfusion). At the end of reperfusion, myocardial infarct size, apoptosis, plasma CK activity, myocardial NOX activity, myocardial caspase-3 expression and activity, myocardial mRNA and protein expressions of vascular peroxidase 1 (VPO1) and NOX2 were measured.</p><p><b>RESULTS</b>Infarct size, ratio of cardiomyocyte apoptosis, mRNA and protein expression of VOP1 and NOX2, serum CK, myocardial NOX and caspase-3 activities in the I/R group were all significantly increased compared to those in the sham group (P < 0.01). Above parameters were similar between I/R + vehicle group and I/R group (all P > 0.05). Infarct size, ratio of cardiomyocyte apoptosis, myocardial mRNA and protein expression of VOP1 and NOX2, serum CK, myocardial NOX and caspase-3 activities were significantly lower in I/R + apocynin group compared to those in I/R group (all P < 0.01).</p><p><b>CONCLUSIONS</b>NOX/VPO pathway plays an important role in mediating I/R-induced myocardial oxidative injury. NOX inhibition could reduce I/R-induced myocardial oxidative injury by attenuating myocardial apoptosis in this model.</p>

Effects of insulin like growth factor-1 on cell viability and tissue factor in vascular endothelial cells / 中华血液学杂志

<p><b>OBJECTIVE</b>To study the effects of insulin like growth factor-1 (IGF-1) on cell viability and tissue factor (TF) in angiotensin II (Ang II) induced vascular endothelial cells and to investigate its mechanisms.</p><p><b>METHODS</b>10(-6) mol/L Ang II was added to human vascular endothelial cells (HUVECs) culture media alone or 30 min after pretreatment with IGF-1 (0.1 microg/ml , 0.5 microg/ml, 2.5 microg/ml). Cell viability and AngII type 1 receptor (AT1-R) mRNA were evaluated after 24 h incubation with AngII. At the optimum concentration of IGF-1 affecting cell viability, the time dependent manner for 12 - 48 h incubation with Ang II was evaluated. TF, NOS and NO were investigated after 24 h incubation with Ang II. In addition, NO synthase inhibitor Nomega-nitro-1-arginine methylester(L-NAME) was added 30 min before addition of IGF-1 and Ang II, and cell viability, TF, AT1-R mRNA, NOS and NO were evaluated after 24 h incubation.</p><p><b>RESULTS</b>(1) Ang II induced a decrease in cell vitality, an upregulation of AT1-R mRNA, an increase in TF, and a decrease in the activity of NOS and content of NO. (2) Pretreatment with IGF-1 significantly inhibited the decreased cell viability and upregulation of AT1-R mRNA. IGF-1 at 0.5 microg/ml showed the most obvious effects. This effect of cell viability recovery was in a time dependent manner during 12 -48 h. (3) IGF-1 also inhibited the increased content of TF, the decreased activity of NOS and the decreased content of NO. (4) The beneficial effects of IGF-1 on cultured endothelial cells were completely abolished by L-NAME.</p><p><b>CONCLUSION</b>IGF-1 pretreatment could enhance the ang II injured cell viability and anti-thrombosis capacity, and the protective effects may be related to activation of NOS-NO signaling pathway which inhibited AT1-R.</p>

Effects of Tongxinluo on cell viability and tissue factor in AngII induced vascular endothelial cells / 中南大学学报(医学版)

OBJECTIVE@#To determine the effects of Tongxinluo on cell viability and tissue factor (TF) in AngII induced vascular endothelial cells and to investigate its mechanism.@*METHODS@#AngII(10(-6)mol/L) was added to human vascular endothelial cells (HUVECs) culture media alone or with various concentration of Tongxinluo drug containing plasma (5%,10%, and 20%) added 30 minutes before AngII. Cell viability was evaluated after 24-hour incubation with AngII in a dose manner. TF, AngII type 1 receptor (AT(1)) mRNA, NO synthase (NOS) and NO were observed after 24-hour incubation with AngII. In addition, NOS inhibitor nomega-nitro-larginine (L-NAME) was added 30 minutes before Tongxinluo and AngII. Cell viability, TF, AT(1)mRNA, the level of NOS and NO were evaluated after 24-hour incubation with Tongxinluo and AngII.@*RESULTS@#Tongxinluo significantly improved AngII induced endothelial cell viability and the effect was the most obvious at 10%. Tongxinluo (10%) decreased the TF and AT(1) mRNA while increased the NOS and NO levels. L-NAME obviously inhibited the effects of Tongxinluo on cell viability, TF, AT(1) mRNA, and NOS and NO levels.@*CONCLUSION@#Up-regulating NOS-NO signaling may be the mechanism of Tongxinluo on cell viability and TF in AngII induced vacular endothelial cells.

Effect of different doses of atorvastatin on adhesion molecules of the patients undergoing percutaneous coronary intervention / 中南大学学报(医学版)

OBJECTIVE@#To determine the effect of different doses of atorvastatin on the serum soluble intercellular adhesion molecules-1 (sICAM-1) in patients undergoing percutaneous coronary intervention (PCI).@*METHODS@#The study consisted of 38 patients with unstable angina and 10 patients with old infarction who underwent elected PCI for stenotic lesions of the coronary artery. Patients were randomly assigned to either aggressive group or conventional one. After PCI the patients took atorvastatin 20 mg per day or 10 mg per day. Blood lipid profile was examined before, and 3 months after the PCI. SICAM-1 was examined before the PCI, 48 hours and 3 months after the PCI.@*RESULTS@#The total cholesterol and LDL-Cholesterol 3 months after the PCI in the 2 groups were lower than those before the PCI (P0.05). sICAM-1 in the 2 groups 48 hours after the PCI significantly higher than that before the PCI (P<0.01). But sICAM-1 in the 2 groups 3 months after the PCI significantly lower than that before the PCI (P<0.01 or P<0.05). The aggressive group showed greater reduction than the conventional group (P<0.01). TC and LDL-C were positively correlated with sICAM-1(r=0.2413, r=0.2691, all P<0.05).@*CONCLUSION@#Atorvastatin 20 mg per day reduces TC, LDL-C, and sICAM-1 to a greater extent than atorvastatin 10 mg per day. The effect on sICAM-1 is partly related to reduce lipid profile.