Effects of reduced glutathione on the ability of antioxidant in maintenance haemodialysis patients

Objective To investigate the effects of reduced glutathione on oxidative stress in maintenance haemodialysis (MHD) patients. Methods All of 68 MHD patients and 30 healthy volunteers were involved in the study. The activity of glutathione peroxidase (GSHPx) was measured by eolorimetry and supemxide dismutase (SOD) in serum was measured by hydroxylamine method. The levels of serum malondialdehyde (MDA) was measured by thiobarbituric acid reaction. The levels of serum total homocysteine (tHcy)was analyzed by enzyme-linked immunosorbent assay (ELISA). All MHD patients were randomly divided into two groups, disease treatment group (38 cases) and disease control group (30 cases), who had undergone haemodialysis for at least three months before the study and were in a stable clinic status without signs of infection or disease activity. In the disease treatment group, 1.2 g of reduced glutathione was infused to the patient at the end of each dialysis treatment for eight weeks, while the parameters for oxidative stress were studied. In the disease control group didn't use reduced glutathione. The levels of GSHPx, SOD, MDA and tHcy in serum were measured before and after the treatment. Chose 30 healthy people as normal control group. Results At the initiation of the investigation, the serum levels of GSHPx and SOD in the disease treatment group and the disease control group were significantly lower than those in the normal control group [(583.74 ± 217.05), (578.82 ±311.94) μmol/L and (349.23 ±80.12), (349.56 ±75.22) kU/L vs (769.06 ± 302.46 ) μmol/L and (428.34 ± 15.23 ) kU/L, P < 0.01 ], while the levels of MDA and tHcy were significantly higher than those in the normal control group [ (4.88 ± 1.13), (4.79 ± 1.42) nmol/L vs (3.56 ± 0.46) nmol/L; (29.65±9.24), (28.76±9.45) μmol/Lvs (24.11±4.45) μmol/L,P<0.01 or<0.05]. After treatment for eight weeks, the levels of GSHPx and SOD were significantly increased and MDA decreased in the disease treatment group compared with those before treatment (P <0.05 or <0.01 ). But there was no significant difference in the disease control group. The levels of GSHPx, SOD and MDA had significant difference between the disease treatment group and the disease control group(P< 0.01 or < 0.05 ). Conclusion Intravenous supplement of reduced glutathione in MHD patients appears to be associated with an improvement of oxidative stress. Key words: Renal dialysis;  Oxidative stress;  Glutathione