The purpose of this study was to determine serum oxidative/antioxidative status in patients with knee osteoarthritis and its relation with prolidase activity, which plays an important role in collagen metabolism. Serum antioxidative status was evaluated by measuring total antioxidant capacity (TAC), thiol level and catalase enzyme activity in patients with osteoarthritis and in healthy controls. Serum oxidative status was evaluated by measuring total peroxide (TP) and lipid hydroperoxide. Oxidative stress index (OSI) was calculated. Prolidase enzyme activity was measured to investigate the collagen metabolism. Serum TAC, thiol level, catalase activity and prolidase activity were significantly lower in patients than in controls (P < 0.001, for all). In contrast, TP, lipid hydroperoxide and OSI values were significantly higher in patients than in controls (P < 0.001 for all). Further, prolidase activity was negatively correlated with TP and OSI, and positively correlated with TAC. The present results indicate that the oxidant parameters increased and antioxidant parameters decreased in patients with osteoarthritis; therefore, these patients may be exposed to a potent oxidative stress. Decreased collagen metabolism may be related with oxidative stress, which has a role in the ethiopathogenesis and/or in the progression of the disease.

The aim of this study was to evaluate the total antioxidant status (TAS), total oxidative status (TOS) and oxidative stress index (OSI) in patients with postmenopausal osteoporosis. We also investigate the relation between bone mineral density and oxidative/antioxidative parameters. Thirty-nine patients with osteoporosis and 26 healthy controls were included in the study. Plasma TAS, TOS levels were determined by using a novel automated methods. Plasma TOS and OSI value were significantly higher, and plasma TAS level was lower in patients than in healthy controls (P < 0.001 for all). There was a significant negative correlation between OSI and BMD in lumbar and femoral neck region (r = -0.63, P < 0.001; r = 0.40, P = 0.018). The results of this study indicated that increased osteoclastic activity and decreased osteoblastic activity may be associated with an imbalance between oxidant and antioxidant status in postmenopausal osteoporosis. Therefore, supplementation of antioxidant-enriched diet to the therapy might shed light on the development of novel therapeutic strategies for osteoporosis.

This study revealed that short-period application of LLLT is effective in pain relief and in the improvement of functional ability and QoL in patients with MPS.

We aimed to investigate the relationship between cortisol levels and bone mineral density (BMD) among premenopausal women with major depression. We compared BMD, plasma cortisol, osteocalcin and C-telopeptide (CTx) levels of 36 premenopausal women with major depression with 41 healthy women who were matched for age and body mass index. Osteocalcin and CTx were used for the evaluation of bone turnover. The clinical diagnosis of major depression was made by using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria. The 21-item Hamilton Rating Scale for Depression was used for the assessment of depressive symptoms. In comparison with the controls, the mean BMD of the depressed women was significantly lower at the lumbar spine and at all sites of the proximal femur (p = 0.02, 0.01). Plasma cortisol levels were significantly higher in depressive patients than in controls (p = 0.001). Osteocalcin was lower and CTx was higher in the patient group than in controls (p = 0.04, p = 0.008). Lumbar and femur BMD scores were negatively correlated with cortisol levels in the patient group. Major depression had important effects on BMD and bone turnover markers. Depression should be considered among risk factors for osteoporosis in premenopausal women.