Statistically higher levels of indole-3-acetic acid (IAA, Figure ) were found in the MCI and AD groups compared to ND, aligning with a recent study reporting significantly higher levels of IAA in the plasma of AD patients compared to control subjects . IAA was previously found upregulated in the CSF of MCI . IAA has shown proinflammatory and prooxidant effects , potentially contributing to neurodegeneration, such that higher levels in MCI might serve as an inflammatory indicator, as previously suggested .