Bungee Jumping Related Stress Response May Suppress Innate Immunity Through the Activation of a Noncanonical Glucocorticoid Signaling Pathway
In this study, David van Westerloo and colleagues from the University of Amsterdam report that bungee jumping resulted in a time-dependent increase in the plasma concentrations of epinephrine, norepinephrine and cortisol; decreased whole blood production of TNF-alpha and IL-8, and a substantial reduction of bacterial phagocytosis by granulocytes and monocytes.
Bungee jumping may represent an interesting and natural model for stress research in humans. High-altitude jumping seems to be associated with a substantial stimulation of the stress or fight-or-flight response.
In the study pretreatment of volunteers with the beta-adrenoreceptor antagonist propranolol left the inhibitory effects on innate immune function intact. Kinome profile analysis however revealed that Fyn inhibition by noncanonical (also termed nongenomic) glucocorticoid signaling most likely mediates the inhibition of innate immunity observed after the jump.
The authors of this study suggest that the stress response associated with bungee jumping leads to a catecholamine-independent immune suppressive phenotype, and that the activation of noncanonical glucocorticoid signaling in the leukocyte compartment may represent a hallmark of the response to acute stress in humans.
SOURCE: Mol Med 2011, 17:180. doi: 10.2119/molmed.2010.00204. Epub 2010 Dec 10