How stress attacks

It’s well-known that continual stress poses a risk to the health. Studies even show that stress is linked to poorer efficacy of the immune system during infection. But how exactly does stress weaken our body’s defences?

Despite the scientific community having conducted research into the effects of psychological stress on the health for many years now, we still have very few answers. Last February, however, a new discovery was made by a team of researchers from the Marseille-Luminy immunology centre which could change that.

According to their findings, the link between stress and immunity is mediated by β2-adrenergic receptors. They came to this conclusion by simulating a situation of chronic stress in mice through the administration of a molecule that stimulates β2-adrenergic receptors the same way stress hormones do. The mice were then exposed to murine cytomegalovirus (MCMV).

The treated mice’s mortality rate was much higher than the control group, at 90% versus 50%. Published in Experimental Medicine, the results1 thus clearly indicate that stress hormone stimulation of β2-adrenergic receptors causes a weakened immune system, therefore paving the way toward new treatment possibilities.

1) β2-adrenergic signals downregulate the innate immune response and reduce host resistance to viral infection. Elisabeth Wieduwild, Mathilde Girard-Madoux, Linda Quatrini, et al. Journal of Experimental Medicine, https://doi.org/10.1084/jem.20190554