Altering Stress Response Systems Through the Gut Microbiome
Gut bacteria change the way an individual responds to its environment. Mice lacking good gut bacteria (referred to as germ-free mice) show abnormally high stress responses. Following an environmental stressor, germ-free mice produce high levels of the stress hormones ACTH and corticosterone. This high stress response can be lessened by giving germ–free mice healthy gut bacteria. However, only young mice display a decreased stress response following the replacement of gut bacteria. Good bacterial colonization must occur early in life to ensure proper development of stress response systems.