The link between gut bacteria and major depressive disorder.
Official title: Gut Microbiota Dysbiosis in Major Depressive Disorder is Associated with Altered Production of Aryl Hydrocarbon Receptor Ligands and Altered Microglia Function
Funded at University of California, San Francisco · NIH-10908335 · Data updated 2026-11-12
This study is looking at how changes in gut bacteria might affect depression, and it's for people with major depressive disorder who want to understand more about how their gut health could be linked to their mood.
Quick facts
| Grant type | Career grant |
|---|---|
| Study type | NIH-funded research |
| Funding institution | University of California, San Francisco NIH-funded |
| Lab location | 1 site (San Francisco, United States) |
| Project start | September 22, 2021 |
| Project end | June 30, 2025 |
| Funding year | 2024 |
| Award (this year) | $201,150 |
| NIH project number | 5K08MH126192-04 |
| Project ID | NIH-10908335 on NIH RePORTER |
Who could benefit from this research
✓Could help
Ideal candidates for this research are individuals diagnosed with major depressive disorder who are currently unmedicated.
✕Less likely to help
Patients who are already receiving treatment for major depressive disorder or those with other psychiatric conditions may not benefit from this research.
What this research studies
This research investigates how changes in gut bacteria, known as dysbiosis, may influence the development of major depressive disorder (MDD). By analyzing stool and blood samples from individuals with MDD and healthy controls, the study aims to understand how gut microbiota affects brain signaling and depressive symptoms. The researchers will focus on a specific metabolic pathway related to tryptophan, which is crucial for serotonin production. This approach could reveal new insights into the biological mechanisms underlying MDD and potential new treatment targets.
Why it matters
Potential benefit: If successful, this research could lead to new therapeutic strategies that target gut microbiota to improve treatment outcomes for patients with major depressive disorder.
How similar studies have gone: Previous research has shown promising results linking gut microbiota to mental health, suggesting that this approach may yield valuable insights.
Where this research is happening
-
University of California, San Francisco
San Francisco, United States Active
Researchers
- Principal investigator: Rampersaud, Ryan — University of California, San Francisco
- Study coordinator: Rampersaud, Ryan
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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.