Gut bacteria that may protect older adults' brains from confusion after surgery
Official title: Gut Microbiota Underlies the Heterogeneity of Aging Brain's Susceptibility to Postoperative Delirium
Funded at Massachusetts General Hospital · NIH-11177632 · Data updated 2026-11-12
This project looks at whether certain gut bacteria and the compound they make (indole-3-propionic acid, IPA) help protect older adults from confusion after surgery.
Quick facts
| Grant type | R01 grant |
|---|---|
| Study type | NIH-funded research |
| Funding institution | Massachusetts General Hospital NIH-funded |
| Lab location | 1 site (Boston, United States) |
| Project start | August 1, 2021 |
| Project end | July 31, 2026 |
| Funding year | 2025 |
| Award (this year) | $622,824 |
| NIH project number | 5R01AG070141-03 |
| Project ID | NIH-11177632 on NIH RePORTER |
Who could benefit from this research
✓Could help
Older adults (age 65 and up) who are planning to have surgery and anesthesia, especially those with existing memory problems or other risk factors for delirium.
✕Less likely to help
People under 65, those not having surgery, or patients whose delirium is driven by non-microbial causes may not benefit from this approach.
What this research studies
Scientists use aged mice to model how older brains react to surgery and anesthesia, comparing mice that develop long-lasting confusion with those that stay clear-headed. They transfer gut microbes from each group into germ-free mice to see if the microbes cause the different outcomes. Chemical analyses (metabolomics) are used to find microbial products that differ, and early work points to IPA and the bacterium Clostridium sporogenes. The team aims to learn whether boosting these bacteria or giving IPA could eventually prevent postoperative delirium in older people.
Why it matters
Potential benefit: If successful, this could lead to new ways to prevent or lessen postoperative delirium in older adults by changing gut bacteria or giving protective metabolites like IPA.
How similar studies have gone: Animal studies and some early human research show gut microbes can influence brain function, but using specific bacteria or IPA to prevent postoperative delirium is a novel approach not yet proven in people.
Where this research is happening
-
Massachusetts General Hospital
Boston, United States Active
Researchers
- Principal investigator: Shen, Shiqian — Massachusetts General Hospital
- Study coordinator: Shen, Shiqian
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About this research
- This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
- Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
- For full project details, budget, and progress reports, visit the official NIH RePORTER page.