Background Evidences have linked aging and the development of age-related diseases to increased levels of oxidative stress (OS). Increased OS in bone enhances osteoblast and osteocyte apoptosis, leading to decrease osteoblast number, and in turn decrease in bone formation (1). Free radicals are toxic to osteoblasts and may stimulate osteoclast differentiation (2). In addition osteoclasts themselves are activated by free-radicals and they in turn produce free-radicals to resorb bone (3). Free radicals activate nuclear factor κβ (NFκβ), a factor responsible for the synthesis of bone-resorbing cytokines such as interleukin-1 and interleukin-6 (4).
Objectives To assess the total antioxidant status (TAS) and oxidative stress in patients with osteoporosis (OP).
Methods Sixty female with positive Dual-Energy X-Ray Absorptiometry (DEXA) results whose ages range between 50 - 60 years old were enrolled in the study and were divided into 2 groups, osteopenia and osteoporosis. Thirty apparently healthy females, age matched with the patients, were kept as a control. TAS and Malondyaldehyde (MDA) were measured in all groups. A pilot study was designed to compare the TAS and MDA between patients with osteopenia and osteoporosis, using the ranges of T-score between the medians of each group (-1.7 to -2.5 and -2.6 to -3.3, respectivly).
Results The TAS values of patients groups (1.59±0.15 mmol/l and 1.05±0.37 mmol/l, were significantly lower than that of the control group (2.18±0.26mmol/l) (p<0.001). MDA values (1.20±0.43 μmol/l and 2.40±0.66 μmol/l, respectively), were significantly higher than that of the control group (0.47±0.14 μmol/l) (p<0.001).
The result of pilot study, showed no difference between these two selected values groups for TAS and MDA, (p-value <0.1and 0.07) respectivlly.
Conclusions The OP patients have lower levels of TAS and higher levels of MDA than the control group. There is no difference between osteopenia and osteoporosis regarding oxidative stress in the pilot study.
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Disclosure of Interest None declared