The effect of exercise on osteoprotegerin and TNF-related apoptosis-inducing ligand in obese patients.

Background: Biomarkers of cardiovascular (CV) risk are tests that predict a patient's risk of future CV events. Recently, two proteins involved in vascular calcification; serum levels of osteoprotegerin (OPG) and tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) have emerged as potentially useful biomarkers. OPG levels are positively correlated with CV risk, whereas TRAIL levels show a negative correlation. Exercise training is known to reduce risk factors for CV disease by improving metabolism, vascular biology and blood flow. This study examined the effects of a 6-month exercise training programme on levels of OPG and TRAIL. Pulse wave velocity (PWV) and high-sensitivity C-reactive protein (hsCRP) were measured for comparative purposes.

Materials And Methods: Overweight and obese patients undertook a 6-month exercise programme. Patients participated in 4 h of primarily aerobic exercise per week of which 2 h were supervised. At the beginning and end of the programme, anthropometric measurements, PWV and serum levels of OPG, TRAIL and hsCRP were measured.

Results: A total of 21 patients (17 men) aged 55.2 ± 10 years completed the programme. Mean body mass index decreased from 34.1 ± 5.8 to 32.6 ± 5.4 kg/m(2) (P<0.05), while waist circumference decreased from 111.8 ± 12.4 to 109.6 ± 12.8 cm (P<0.05). PWV decreased from 9.2 to 8.5 m/s (P<0.02). OPG, TRAIL and hsCRP levels did not change significantly.

Conclusions: Exercise training reduced PWV but not OPG, TRAIL or hsCRP in this population. These data suggest that while an intervention of this nature improves vascular tone, it does not exert significant effects on serum biomarkers related to atherosclerotic inflammation and calcification.