The Changes And Clinical Significance Of Glutathione Redox-state In Patients With Coronary Heart Disease

Objective: To study the changes and clinical significance of glutathione redox-state in patients with coronary heart disease (CHD).Methods: Total of 118 hospitalized patients in cardiovascular wards of the first affiliated hospital of Soochow University from Sep. 2007 to Jan. 2008 was selected. Based on both with or without atherogenic risk factors and the result of coronary arteriongraphy (CAG), they were calssified into 3 groups: control group (n=30), risk group (n=28) and CHD group (n=60). According to clinical situation CHD group was divided into 2 subgroups: unstable angina pectoris (UAP) group (n=32) and acute myocardial infarction (AMI) group (n=28). Samples of peripheral ulnar venous blood with natrium citricum as anticoagulant were obtained from aforesaid patients on empty stomach in next morning after hospitalization, then the samples were centrifuged and the plasma concentrations of reduced glutathione (GSH) and oxidized glutathione (GSSG) were measured by using glutathione reductase recycling method (GR-DTNB) and spectrophotometer. Redox potential (EhGSH/GSSG) was calculated using Nernst equation according to the concentrations of GSH and GSSG. At the same time samples of peripheral ulnar venous blood were obtained to measure the concentrations of high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). Every patient undertook echocardiograhy and left ventricular ejection fraction (LVEF) was calculated within the first three days.Results: 1. The concentration of GSH was significantly lower in CHD group compared with control group [(5.63±0.73)μmol/L vs (6.44±0.98)μmol/L, P<0.05]. The concentration of GSSG gradually increased from control group, to risk group, then to CHD group, they were (1.04±0.05)μmol/L, (1.11±0.05)μmol/L and (1.13±0.07)μmol/L respectively. There was significant difference between CHD group and risk group and control group. The value of redox potential also gradually increased in the three groups like GSSG, and they were (-132.16±3.95) mV, (-129.31±3.18) mV and (-127.65±3.69) mV. There was significant difference between CHD group and risk group and control group.2. There was no significant difference between the UAP subgroup and AMI subgroup in concentrations of plasma GSH,GSSG and the value of redox potential [(5.63±0.73)μmol/L vs (5.62±0.76)μmol/L, (1.13±0.07)μmol/L vs (1.13±0.07)μmol/L, (-127.64±3.69) mV vs (-127.67±3.86) mV, P>0.05].3. The concentration of GSH had a positive correlation with the value of HDL-C ( r=0.321, P<0.05) and a negative correlation with the value of LDL-C ( r=-0.272, P<0.05); The concentration of GSSG had a negative correlation with the value of HDL-C ( r=-0.270, P<0.05) and a positive correlation with the value of LDL-C ( r=0.371, P<0.05); The value of redox potential had a negative correlation with the value of HDL-C ( r=-0.352, P<0.05) and a positive correlation with the value of LDL-C ( r=0.343, P<0.05).4. There were no significant difference among the CHD patients having different numbers of coronary artery that have significant atherosclerotic plaques in concentrations of plasma GSH [(5.65±0.66)μmol/L, (5.61±0.87)μmol/L, (5.59±0.77)μmol/L, P>0.05],GSSG [ (1.11±0.08)μmol/L, (1.15±0.05)μmol/L, (1.16±0.07)μmol/L, P>0.05] and the value of redox potential [(-128.10±3.19) mV, (-127.25±4.24) mV, (-127.15±4.19) mV, P>0.05].Conclusions: 1. The concentration of GSH decreased, the concentration of GSSG and the value of redox potential increased in CHD patients, redox status shifted to oxidizied direction. All these show that body's antioxidant capacity decreases and the oxidative stress exists in artherosclerosis, and improving this situation may decelerate or prevent the formation and progress of artherosclerosis.2. As the numbers of coronary artery with significant atherosclerotic plaques increased, the GSH/GSSG redox state had no significant change, suggesting that the numbers of coronary artery with lesions can not count as an independent risk indicator to evaluate the extent of oxidative stress status in patients with CHD.3. The concentration of GSH had a positive correlation with the concentration of HDL-C and a negative correlation with the concentration of LDL-C. The relationship of the concentration of GSH and the value of redox potential with the concentration of HDL-C and the concentration of LDL-C is in contrast with GSH. All these show that there is a certain degree of relevance between oxidative stress and hyperlipoidemia, and the level of the GSH/GSSG antioxidant system is an indirect index which can evaluate the level of blood lipids and the effection of lipids-lowering drugs.