Fico, Brandon G.

The primary purpose of this study was to investigate the effect of acute high-intensity interval exercise (HIIE) vs. continuous moderate-intensity exercise (CME) on serum CTRP9 and brachial FMD responses in obese and normal-weight subjects. Sixteen participants (9 obese and 7 normal-weight) completed HIIE and CME in a randomized fashion. Our results showed a significant time effect for CTRP9 immediately following acute HIIE and CME in both groups. Furthermore, both significant treatment by time and group by time interactions for FMD were observed following both exercise protocols, with greater CME-induced FMD response in obese subjects than normal-weight subjects. Additionally, a positive correlation in percent change (baseline to peak) between CTRP9 and FMD was observed following acute CME. These findings support acute CME for improvement of endothelial function in obesity. Furthermore, the novel results from this study provide a foundation for additional examination of the mechanisms of exercise-mediated CTRP9 on endothelial function.

The secular issue of obesity has been linked to increased inflammatory mediators, such as calprotectin (S100A8/A9). This study examined the effect of acute aerobic exercise on plasma calprotectin response in obese and normal-weight subjects and its relationship with inflammatory cytokine (IL-6). All subjects (11 obese and 10 normal-weight) performed 30 minutes of treadmill exercise at 75% maximal oxygen consumption (VO2max). Blood samples were collected prior to, immediately following exercise, and one hour after exercise. Our results showed higher baseline levels of calprotectin in obese subjects than normal-weight subjects. While acute aerobic exercise increased an elevation in calprotectin and IL-6, no difference was found between two groups. Furthermore, a positive relationship was observed between calprotectin area-under-the curve “with respect to increase” (AUCi) and IL-6 AUCi, even after controlling for cardiorespiratory fitness (VO2max). Our results support previous finding that IL-6 may potentially regulate calprotectin expression in skeletal muscle during exercise.