Randomized Controlled Trial Investigating Potential Effects of Relaxation on Mitochondrial Function in Immune Cells: A Pilot Experiment.

This study aimed to investigate the effect of a relaxation response induced by hypnosis on the mitochondrial energy production of immune cells compared to an everyday relaxing situation. N = 47 chronically stressed individuals (88% women) with at least moderate suggestibility were randomized to a hypnosis (20min relaxation hypnosis; n = 20) or a control condition (20min documentary; n = 22). Before and after intervention, peripheral blood was collected. The primary outcomes were mitochondrial respiration and density in immune cells measured by high-resolution respirometry and citrate synthase activity assays. As secondary outcome, perceived stress, anxiety, and depressive mood were assessed. The intervention led to no significant Group × Time effects on mitochondrial bioenergetic parameters but a significant Time effect (η =.09 -.10). Thus, there were no differences in the experimental conditions concerning the measured parameters of mitochondrial bioenergetics. Exploratory subanalyses indicated that stress, anxiety, and depressive mood were linked to lower mitochondrial respiration. Individuals with higher anxiety had less decrease in routine respiration over time than those with lower anxiety (η =.09). This study explores the effects of relaxation in the form of hypnosis compared to those of watching a video on the energy metabolism of immune cells. Relaxation, whether in targeted form (hypnosis) or untargeted (documentary), affected mitochondrial respiration. Further research should focus on the long-term effects of relaxation on bioenergetics. The trial was retrospectively registered on 07/12/2021, DRKS00027356, https://drks.de/search/de/trial/DRKS00027356.