Determination of plasma gluthatione reductase enzyme activity in osteoporotic women

Osteoporosis is a disease of high prevalence with increased bone loss. Free radicals have been proved to be involved in bone resorption. Glutathione reductase (GR) plays an essential role in cell defense against reactive oxygen metabolites by sustaining the reduced status of an important antioxidant, glutathione. In the present study GR activity of plasma as an antioxidant enzyme in relation to Bone Mineral Density (BMD) was investigated. GR activity was measured spectrophotometrically at 339 nm in 138 women. Participants were selected by inclusion and exclusion criteria from those who were referred to Jamie Clinic in Tehran for BMD evaluation. Plasma activity of GR (Mean± SD) was: 64.44 ± 37.68 U/L in the control group, 75.49 ± 54.84 U/L in the total patients [(mild Osteopenia + severe Osteopenia and Osteoporosis) (Tscore<-1)] and 80.48 ± 61.91 U/L in the patients with severe Osteopenia and Osteoporosis respectively (Tscore <-1.7). The results show that plasma activity of GR in patients with bone deficiency was higher than the control group. The difference was more pronounced between controls and the patients with severe Osteopenia and Osteoporosis, than those differences between controls and the total patients. Femur Tscore adjustment with age and BMI showed significant negative correlation with the plasma activity of GR in all subjects.