Tirzepatide showed the highest rate of blood-brain barrier crossing among four incretin drugs tested in mice, suggesting the strongest potential for direct brain effects.
Tirzepatide: highest brain uptakeAmong four incretin receptor agonists, tirzepatide showed the greatest ability to cross the blood-brain barrier in mice
What the researchers found
Tirzepatide had the highest rate of blood-brain barrier crossing among the four incretin receptor agonists tested, suggesting it may be the most promising for direct brain effects.
Why it matters
If incretin drugs can cross the blood-brain barrier, they might directly protect brain cells in diseases like Alzheimer's and Parkinson's. Knowing which drugs cross best helps prioritize which ones to study further.
The numbers in context
Four drugs tested: albiglutide, dulaglutide, DA5-CH, and tirzepatide. Adult male CD-1 mice were used with radioactive labeling (125I or 14C).
How the study worked
Researchers injected adult male mice with radioactively labeled versions of four drugs and measured brain uptake using multiple-time regression analysis.
Who was studied
Adult male CD-1 mice
What this study cannot tell us
This was an animal study in mice, so brain uptake rates may differ in humans. The study measured how much drug reaches the brain but did not test whether it produces therapeutic effects there.
How to read the evidence
Rated preliminary: pharmacokinetic study measuring brain uptake in mice, but does not test whether brain exposure translates to therapeutic effects.
When this study was published
Published in 2024. Part of growing interest in repurposing diabetes drugs for neurodegenerative diseases.
The bigger picture
Multiple incretin drugs show promise for neurodegenerative diseases. Knowing which ones actually reach the brain helps prioritize which should advance to clinical trials for Alzheimer's and Parkinson's.
Questions still open
- Does higher brain uptake translate to greater neuroprotection?
- Would the same ranking hold in humans with different blood-brain barrier properties?
Common questions
Could diabetes drugs treat Alzheimer's?
Why does brain entry matter?
Read the original research
Brain uptake pharmacokinetics of albiglutide, dulaglutide, tirzepatide, and DA5-CH in the search for new treatments of Alzheimer's and Parkinson's diseases.
Tissue barriers, 12(4), 2292461
Citation
Rhea, Elizabeth M; Babin, Alice; Thomas, Peter; Omer, Mohamed; Weaver, Riley; Hansen, Kim; Banks, William A; Talbot, Konrad. (2024). Brain uptake pharmacokinetics of albiglutide, dulaglutide, tirzepatide, and DA5-CH in the search for new treatments of Alzheimer's and Parkinson's diseases.. Tissue barriers, 12(4), 2292461. https://doi.org/10.1080/21688370.2023.2292461