Human blood mononuclear cell in vitro cytokine response before and after two different strenuous exercise bouts in the presence of bloodroot and Echinacea extracts

The purpose of this multidisciplinary investigation was to characterize cytokine production by human blood mononuclear cells after 2 contrasting exercise bouts (a maximal graded oxygen consumption [VO2max] test and 90 min of cycling at 85% of ventilatory threshold [VT]) when stimulated in vitro with extracts from bloodroot (Sanguinaria canadensis), coneflower (Echinacea tennesseensis), or solvent vehicle controls. Blood was sampled pre- and post-exercise. Production of TNF, IL-1β, and IL-10 were measured at 24, 48, and 72 h, respectively. In the VO2max test there was a main effect of exercise such that exercise increased cytokine synthesis and a main effect of stimulant such that bloodroot extracts significantly increased cytokine production compared to other stimulants or controls. In the 90-min bout, there was a main effect of exercise for TNF and IL-1β (but not IL-10) such that exercise decreased cytokine synthesis and a main effect of stimulant such that bloodroot extracts significantly increased cytokine production compared to other stimulants or controls, with exercise × stimulant interactions for both IL-1β and IL-10. A similar though weaker effect was seen with Echinacea extracts; subsequent biochemical analyses suggested this was related to alkamide decay during 3 years undisturbed storage at ultralow (− 80 °C) temperature. In this study, the VO2max test was associated with enhanced cytokine production whereas the 90-min cycling at 85% VT was associated with suppressed cytokine production. Bloodroot extracts were able to increase cytokine production in both contexts. Herbal extracts purported to offset exercise-associated effects on immune activity warrant continued investigation.