Abstract 16501: VEGF and VEGF-R1 Levels in Skeletal Muscle of PAD Patients: A Report From the AMNESTI (Angiogenesis and Mechanisms of Exercise Training in PAD) Clinical Trial
Background: A common manifestation of peripheral artery disease (PAD) is intermittent claudication (IC), and an effective treatment for IC is supervised exercise training (SET). The mechanism of improvement with exercise training in PAD patients is thought to involve angiogenesis, or the growth of new blood vessels. Vascular endothelial growth factor (VEGF) and its receptors have been studied extensively and implicated in the process of angiogenesis in human skeletal muscle. An aim of the present study was two-fold: (1) to identify whether PAD patients had increased muscle concentration of VEGF or VEGF-R1 when compared to control patients, and (2) to evaluate whether exercise training in PAD patients was associated with an increased muscle concentration of VEGF or VEGF-R1.
Methods: At baseline, 34 PAD patients and 32 control patients underwent gastrocnemius muscle biopsy. Additionally, 11 PAD patients underwent muscle biopsy after home exercise training (HET) and 13 PAD patients underwent muscle biopsy after 3 weeks and 12 weeks of SET. All muscle biopsies were obtained during a resting state to avoid any effects of acute exercise. VEGF and VEGF-R1 concentrations were measured in skeletal muscle lysates by ELISA.
Results: Muscle concentrations of VEGF and VEGF-R1 were significantly lower in PAD patients when compared with controls prior to exercise training [Figure 1]. VEGF levels decreased after 3 weeks and 12 weeks of SET, while concentrations did not change after 12 weeks of HET [Figure 1]. Muscle concentrations of VEGF-R1 did not change in either group after exercise training.
Discussion: Muscle concentrations of VEGF and VEGF-R1 are lower in PAD patients when compared to controls at baseline. SET is associated with additional reduction in VEGF levels despite a known improvement in peak oxygen consumption in patients who undergo SET. Further investigation into the mechanism of exercise improvement in PAD patients is warranted.
- © 2011 by American Heart Association, Inc.