Elevated plasma intestinal fatty acid binding protein and aberrant lipid metabolism predict post-stroke depression

Post-stroke depression (PSD) is the most common mood disorder caused by stroke. Stroke might bring about increased intestinal permeability accompanied by gut microbiota changes. According to the "gut-brain" axis hypothesis, increased intestinal permeability may contribute to PSD. Therefore, we investigated the association between increased intestinal permeability and the occurrence of PSD. Intestinal fatty acid binding protein (iFABP) is responsible for intestinal fatty acid absorption and transport and is often considered a biomarker of gut hyperpermeability, also known as leaky gut. We enrolled 48 healthy controls (HCs), 48 stroke patients without depression, and 48 PSD patients in this study. Plasma iFABP was measured in the three groups. CRP, LBP, and sCD14 were quantified for bacterial infection assessment. In addition, clinical laboratory indicators of lipid metabolism were assessed. The PSD patients exhibited higher iFABP levels compared with HCs and non-depressed stroke patients. Using OPLS discriminant analysis, four proteins (ApoA1, HDL-C, iFABP, and Lp(a)) were identified as potential biomarkers for distinguishing PSD patients from non-depression stroke patients. Our study discovered that elevated plasma iFABP levels in PSD patients correlated with the degree of depression, along with disturbed lipid metabolism. These findings also suggested the need to consider the role of a leaky gut in depression after stroke.