We performed this study to investigate whether plasma glutathione reductase (GR) activity is correlated with the erythrocyte reduced glutathione (GSH)/glutathione disulfide (GSSG) ratio in endotoxemic rats and if the decrease in GR activity is asociat...
We performed this study to investigate whether plasma glutathione reductase (GR) activity is correlated with the erythrocyte reduced glutathione (GSH)/glutathione disulfide (GSSG) ratio in endotoxemic rats and if the decrease in GR activity is asociated with the increase in the mortality of patients with septic shock. This study consisted of a laboratory study conducted on male SD rats and a prospective observational study conducted in a 12-bed ICU of a tertiary referal hospital.To induce endotoxemia in rats, vehicle, LPS at dosages of 5 (LD-LPS), or 10 mg/kg (HD-LPS) were injected into a tail vein. Survival was observed for 72 hours,and a separated set of animals were euthanized at 6 hours post-LPS. Consecutive patients admitted to the ICU with septic shock were enrolled. Acording to the 28-day mortality, the enrolled patients were divided into the two groups: the survivors and the non-survivors. We obtained plasma samples at admission (0 h), 24 (24 h), and 72 hours after admision (72 h). The survival rate in the HD-LPS group was lower than that in the LD-LPS group. Erythrocyte GSH level, GSH/GSSG ratio, and GR and glutathione peroxidase (GPx) activities in the HD-LPS group were lower than those in the LD-LPS group, but GSSG and MDA levels in the HD-LPS group were higher than the LD-LPS group. The Spearman``s correlation coefficient between the erythrocyte GSH/GSSG ratio and the plasma GR activity was 0.782. Among 50 patients, 34 were the survivors and 16 were the non-survivors. The decreases in plasma total glutathione level and GR activity at 24 h were asociated with the increase in the mortality of patients with septic shock. Plasma GR activity was well correlated with erythrocyte GSH/GSSG ratio and the decreases in plasma total glutathione level and GR activity were asociated with the increase in the mortality of patients with septic shock.