Stress doesn't just wear you down mentally — it may actually age your immune system through your gut. A new mouse study published in Cell Stem Cell reveals that psychological stress disrupts gut bacteria, which in turn damages blood-forming stem cells in the bone marrow. The culprit? A drop in a key gut microbe and a cellular "cleanup" compound called spermidine.
Stress doesn't just wear you down mentally — it may actually age your immune system through your gut. A new study published in Cell Stem Cell (July 2) reveals that psychological stress triggers a chain reaction: it suppresses activity in specific brain regions, disrupts the gut microbiome, and ultimately damages hematopoietic stem cells (HSCs) — the blood-forming cells in bone marrow responsible for producing immune cells.
Researchers at Sun Yat-sen University used four different mouse stress models to map this brain-gut-bone marrow axis. They found that stress reduced activity in the medial prefrontal cortex and periaqueductal gray, leading to a loss of Lactobacillus reuteri (a gut microbe key to microbial balance) and lower levels of spermidine, a compound that helps clear out damaged cells. The result: fewer HSCs and reduced lymphocyte production — hallmarks of immune aging.
Key Takeaways:
Why it matters: This research offers a concrete biological mechanism linking chronic stress to immune decline — and opens the door to gut-based or lifestyle interventions that could help preserve immune function during aging or prolonged stress.
