Altered profile of cytokines, growth factors in AS patients after exercise
Exercise results in an altered pattern of change in circulating growth factors and cytokines, and greater increases in pro-inflammatory cytokines in patients with asymptomatic, moderate-to-severe aortic valve stenosis (AS), a new study shows.
The study included 32 patients (16 males, 17 females) with asymptomatic, moderate-to-severe AS. A separate group of age- and sex-matched individuals was established as a control group. Those with a history of angina, stroke, myocardial infarction, cancer or dizziness, among other complications, were excluded.
Participants performed exercise on a bicycle ergometer and received a continuous stress echocardiographic examination. Plasma levels of interleukin (IL)-10, IL-6, hepatocyte growth factor (HGF), transforming growth factor (TGF)-β and vascular endothelial growth factor (VEGF) were measured at rest, at peak exercise, and at 1 hour and 24 hours after exercise.
The stress test was significantly shorter in the AS patients (9.0±1.9 minutes) compared with controls (10.8±2.7 minutes; p=0.008), while the maximum workload was significantly lower (81.3±21.1 W; p=0.002).
The levels of all the markers in both groups increased after exercise (p<0.0001 for all). IL-10 and IL-6 reached significantly higher maximum levels in the AS patients (p<0.005 for all).
In controls, the maximum levels of VEGF, IL-10 and IL-6 were observed during peak exercise. In AS patients, this was observed 1 hour after exercise. On the other hand, maximum TGF-β levels were observed 1 hour after exercise in both groups.
The highest HGF values were observed during peak exercise in AS patients and after the exercise in controls. HGF levels in AS patients were higher during peak exercise and 1 hour after exercise compared with controls (p=0.0001).
After 24 hours, only TGF-β remained elevated relative to resting values in both groups (p=0.0001). No association with workload and heart rate was observed.
The findings suggest that asymptomatic, moderate-to-severe AS patients experience an inflammatory state after exercise.