Abstract 618: Inflammatory Biomarkers are Improved Subsequent to an Aerobic Exercise Training Intervention in African Americans

Abstract

African Americans (AA) have the highest prevalence of hypertension (HTN) in the world which may emanate from their predisposition to heightened endothelial inflammation. Long-term exposure of the endothelium to proinflammatory cytokines leads to increased oxidative stress, inflammation, and endothelial dysfunction which support an environment favoring HTN. It is thought that the balance between pro- and anti-inflammation plays a crucial role as a determinant of endothelial homeostasis and health. Positive associations between proinflammatory markers such as C-reactive protein (CRP) and interleukin-6 (IL-6) with HTN have been reported. Elevated circulating levels of the anti-inflammatory cytokine, interleukin-10 (IL-10) have been associated with improved endothelial function. In addition, aerobic exercise training (AEXT) has been associated with favorable endothelial adaptations. PURPOSE: To evaluate the effect of a 6-month AEXT intervention on the inflammatory biomarkers CRP, IL-6, and IL-10 in African Americans. A secondary purpose was to determine whether there are relationships between the changes in CRP, IL-6, and IL-10 subsequent to the 6-month AEXT intervention. METHODS: A Pre-Post design was employed following the completion of screening, dietary stabilization, and antihypertensive medication tapering. Subjects were sedentary, putatively healthy, 45-71 y/o AA men and women. Baseline evaluation included fasting blood sampling and graded exercise testing (GXT). Participants engaged in 6-months of AEXT. At the conclusion of the AEXT intervention, baseline tests were repeated. Concentrations of CRP, IL-6, and IL-10 were determined using an ELISA. RESULTS: There was a significant decrease in CRP (n=37; p=0.01) and a significant decrease in IL-6 (n=32; p=0.04) following AEXT. IL-10 was increased following the AEXT intervention, however it was not statistically significant (n=26; p=0.08). There were no significant relationships between the changes in the inflammatory biomarkers measured. CONCLUSION: Based on the favorable adaptations in the inflammatory biomarkers CRP and IL-6, AEXT may be a viable, nonpharmacologic method to reduce the risk for HTN in AA by improving inflammation status and endothelial function.