The impact of exercise on growth factors (VEGF and FGF2): results from a 12-month randomized intervention trial

BACKGROUND: Vascular endothelial growth factor (VEGF) and Fibroblast growth factor-2 (FGF2) are angiogenic cytokines in normal tissues and tumors. Evidence suggests that increased growth factor expression in adipose tissue leads to improved vascularity and decreased hypoxia, fibrosis, and inflammation, which may, in turn, reduce post-menopausal breast cancer risk. OBJECTIVE: We investigated whether or not exercise had dose-response effects on levels of plasma VEGF and FGF2 in postmenopausal women. METHODS: Four hundred previously inactive but healthy postmenopausal women aged 50–74 years of age were randomized to 150 or 300 min per week of aerobic exercise in a year-long exercise intervention. VEGF and FGF2 were measured from fasting serum samples with a custom-plex multiplex assay. RESULTS: A high compared to moderate volume of aerobic exercise did not cause chronic changes in plasma VEGF or FGF2 levels in intention-to-treat or per-protocol analyses. CONCLUSIONS: We did not detect differences in growth factor levels related to increasing doses of exercise. It is unlikely that changes in VEGF and FGF2 levels mediate the reduction in risk of post-menopausal breast cancer development in associated with increased levels of exercise. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT01435005.