Excessive or persistent proinflammatory
cytokine production plays a central role in
autoimmune diseases. Acute activation of the sympathetic nervous system attenuates the innate immune response. However, both the autonomic nervous system and innate immune system are regarded as systems that cannot be voluntarily influenced. Herein, we evaluated the effects of a training program on the autonomic nervous system and innate immune response. Healthy volunteers were randomized to either the intervention (n = 12) or control group (n = 12). Subjects in the intervention group were trained for 10 d in
meditation (third eye
meditation), breathing techniques (i.a., cyclic
hyperventilation followed by breath retention), and exposure to cold (i.a., immersions in
ice cold water). The control group was not trained. Subsequently, all subjects underwent experimental
endotoxemia (i.v. administration of 2 ng/kg
Escherichia coli endotoxin). In the intervention group, practicing the learned techniques resulted in intermittent
respiratory alkalosis and
hypoxia resulting in profoundly increased plasma
epinephrine levels. In the intervention group, plasma levels of the anti-inflammatory
cytokine IL-10 increased more rapidly after
endotoxin administration, correlated strongly with preceding
epinephrine levels, and were higher. Levels of proinflammatory mediators TNF-α,
IL-6, and
IL-8 were lower in the intervention group and correlated negatively with
IL-10 levels. Finally, flu-like symptoms were lower in the intervention group. In conclusion, we demonstrate that voluntary activation of the sympathetic nervous system results in
epinephrine release and subsequent suppression of the innate immune response in humans in vivo. These results could have important implications for the treatment of conditions associated with excessive or persistent
inflammation, such as
autoimmune diseases.