Is there a role of free oxygen radicals in primary male osteoporosis?

OBJECTIVE: There is not enough evidence about the relationship between free radicals and male osteoporosis. In this study we investigated the role of free oxygen radicals and antioxidants on male osteoporosis in 31 male patients with primary osteoporosis and 21 subjects as controls. METHODS: Bone mineral densities (BMD) of the lumbar and femoral neck region were evaluated using dual energy X-ray absorbsiometry. Serum malondialdehyde (MDA) and nitric oxide (NO) levels and superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were measured by analytical methods. In addition, serum osteocalcine and C telopeptide levels were determined to evaluate bone turnover MDA and NO levels and SOD activity were significantly increased (p < 0.05) in osteoporotic males. RESULTS: There was a negative correlation between SOD and lumbar BMD levels (r= -0.328; p = 0.021). The same trend was observed between NO and lumbar BMD (r = -0.473; p = 0.001) and femoral neck BMD values (r = -0.540; p = 0.000). There was no significant correlation between free radical levels and bone turnover markers. CONCLUSION: The data indicate an increase in free oxygen radical levels. As a result, antioxidant defenses would compromise in primary male osteoporotic patients. Therefore, it may be suggested that oxidative stress plays an important role in the pathophysiology of primary male osteoporosis.

No effect of GA-AS (904 nm) laser irradiation on the intact skin of the injured rat sciatic nerve.

We evaluated the electrophysiological and histopathological effects of low-energy gallium arsenide (904 nm) laser irradiation on the intact skin injured rat sciatic nerve. Twenty-four male Wistar rats were divided into three groups ( n=8 each). At the level of proximal third of the femur the sciatic nerve was crushed bilaterally with an aneurysm clip (Aesculap FE 751, Tuttingen, Germany) for half a second. A gallium arsenide laser (wavelength 904 nm, pulse duration 220 ns, peak power per pulse 27 W, spot size 0.28 cm2, pulse repetition rate 16, 128 and 1000 Hz; total applied energy density 0.31, 2.48 and 19 J/cm2) was applied to the right sciatic nerve for 15 min daily at the same time on 7 consecutive days. The same procedure was performed on the left sciatic nerve of same animal, but without radiation emission, and this was accepted as control. Compound muscle action potentials were recorded from right and left sides in all three groups before surgery, just at the end of injury, at the 24th hour and on the 14th and 21st days of injury in all rats using a BIOPAC MP 100 Acquisition System Version 3.5.7 (Santa Barbara, USA). BIOPAC Acknowledge Analysis Software (ACK 100 W) was used to measure CMAP amplitude, area, proximal and distal latency, total duration and conduction velocity. Twenty-one days after injury, the rats were sacrificed. The sciatic nerves of the operated parts were harvested from the right and left sides. Histopathological evaluation was performed by light microscopy. Statistical evaluation was done using analysis of variance for two factors (right and left sides) repeated-measures (CMAP variables within groups) and the Tukey-Kramer Honestly Significant Difference test (CMAP variables between laser groups). The significance was set at p < 0.05. No statistically significant difference (p > 0.05) was found regarding the amplitude, area, duration and conduction velocity of CMAP for each applied dose (0.31, 2.48 and 19 J/cm2) on the irradiated (right) side and the control (left) side, or between irradiated groups. Twenty-one days after injury there were no qualitative differences in the morphological pattern of the regenerated nerve fibres in either irradiated (0.31, 2.48 and 19 J/cm2) or control nerves when evaluated by light microscopy. This study showed that low-energy GaAs irradiation did not have any effect on the injured rat sciatic nerve.

Acute electrophysiological effect of pulsed gallium-arsenide low-energy laser irradiation on isolated frog sciatic nerve.

We evaluated the acute electrophysiological effects of low-energy pulsed laser irradiation on isolated frog sciatic nerve measured by extracellular recording technique. A pulsed gallium-arsenide (GaAs) laser (wavelength: 904 nm, pulse duration 220 ns, peak power per pulse: 27W, spot size: 0.28 cm(2), total applied energy density: 0.005-2.5J/cm(2)) was used for the experiment. Sixty isolated nerves were divided into six groups (n=10), each of which received a different laser dose. In each group, action potentials were recorded before laser irradiation which served as the control data. The extracellular action potentials were recorded for each combination of 1, 3, 5, 7, 10, 13 and 15 minutes of irradiation time and 4, 8, 16, 32, 64 and 128 repetition frequency by using a BIOPAC MP 100 Acquisition System Version 3.5.7 (Santa Barbara, USA). Action potential amplitude, area, duration and conduction velocity were measured. Statistical evaluation was performed using repeated measures variance analysis by SPSS 9.0. There were no statistically significant differences for action potential amplitude, area and conduction velocity among the laser groups and control data (p>0.05). The study showed that low-energy GaAs irradiation at 4-128 Hz repetition frequencies administered for irradiation times of 1-15 min generates no effect on action potential amplitude, area, duration and conduction velocity in isolated frog sciatic nerve.

A case of ochronosis: upper extremity involvement.

We present an ochronotic patient with spondylosis and upper extremity involvement. We also evaluated radiologic findings of joints that were involved and MRI features of the lumbar spine.

Lumbar and femoral bone mineral density in type 2 Turkish diabetic patients.

The relationship between type 2 diabetes and osteoporosis has not been well established. We studied a population composed of 161 post-menopausal women with type 2 diabetes and a control group. We examined bone mineral density with the dual-energy X-ray absorptiometry(DXA) technique at the lumbar and femoral regions and in a subgroup of patients, we also measured the levels of markers of bone remodelling. We found significantly higher levels of bone mineral density at the lumbar and femoral levels in the diabetic subjects compared with the control group. Moreover, we found higher level of urinary calcium in the controls. On the basis of these results, we suggest that osteoporosis cannot be considered a complication of type 2 diabetes.