Association Of Brain-derived Neurotrophic Factor With Physical Activity And Cardiovascular Disease Risk Factors

Abstract

Brain-derived neurotrophic factor (BDNF) is an important molecular mediator of structural and functional plasticity in the brain. It is now acceptable that regular physical activity increases BDNF level in various brain regions and it has been believed that serum-BDNF levels could be used to indirectly assess brain-BDNF levels. However, recent studies provided possibilities that circulating BDNF may not reflect brain-BDNF and that it may be associated with cardiovascular disease risk factors (CDRF). PURPOSE: To examine the association of serum BDNF with maximal oxygen consumption (VO2max/kg), moderate physical activity (MPAT) and CDRFs. METHODS: Healthy young adult (age range: 21-29 years, n=88) and middle-aged adult (41-55 years, n=447) men were participated as a part of the Preventive Health Study, Sports Science Institute, Yong-in Univ., Korea. When coming to laboratory after an overnight fast, participants were asked to take a 30-min rest followed by venous blood sampling. After the blood sampling, VO2max/kg was assessed by a maximal treadmill test. Serum-BDNF was analyzed by ELISA kits (Bio-Rad, USA), while total cholesterol (TC), triglyceride (TG) and low- and high-density lipoprotein cholesterol (LDL and HDL) were measured by UV methods (Hitachi U-2800, Japan). MPAT was measured by using international physical activity questionnaire. Pearson product moment correlation was conducted to analyze an association of serum BDNF to MPAT and VO2max/kg within each group. RESULTS: Our study resulted in a significantly inverse relationship between serum BDNF and MPAT (r=-0.79 and r=-0.78) and VO2max/kg (r=-0.42 and r=-0.33) in young and middle-aged adult groups respectively (P<0.0001). Our results showed a significant, linear correlation between serum BDNF and BMI (r=0.80 and r=0.81), SBP (r=0.33 and r=0.24) and triglyceride level (r=0.31 and r=0.35) in young and middle-aged adult groups respectively (P<0.0001). CONCLUSION: In conclusion, our data show that serum BNDF is associated with increases in cardiovascular disease risk factors and inversely associated with levels of physical activity within each aged group. However, because of the cross-sectional nature of the study, a future research is warranted to elucidate the possible mechanisms for these relationships for circulatory BDNF.