Published online Aug 19, 2025. doi: 10.5498/wjp.v15.i8.106971
Revised: June 2, 2025
Accepted: June 24, 2025
Published online: August 19, 2025
Processing time: 139 Days and 2.9 Hours
Diamine oxidase (DAO) is secreted by epithelial cells in the intestinal villi, and its serum levels are elevated after intestinal mucosal damage. d-lactate (D-LA) is a gut microbial metabolite that can enter the systemic circulation if intestinal barrier function is impaired. Both DAO and D-LA are serum markers of small bowel mucosal integrity, and can be valuable biomarkers of intestinal barrier damage in inflammatory bowel disease (IBD). Intestinal barrier dysfunction was recently found to contribute to psychological symptoms in IBD patients. However, the correlations among DAO, D-LA, psychological symptoms, and disease activity in IBD remain unexplored.
To explore the correlations between serum markers of intestinal barrier dysfun
We enrolled of 126 participants in this study. Psychological symptom questionnaires (depression, patient health questionnaire-9; anxiety, generalized anxiety disorder-7; and stress, perceived stress scale) and a quality of life (QOL) questionnaire (IBD questionnaire 32) were collected at the baseline. Serum DAO and D-LA levels were measured to assess intestinal barrier integrity. Receiver operating characteristic (ROC) curves were used to identify candidate markers of psychological symptoms and disease activity in IBD patients. Logistic regression was applied, with DAO as an independent variable for predicting psychological symptoms in IBD.
Serum DAO levels were significantly higher in IBD patients with moderate-to-severe psychological symptoms than in patients with mild or no psychological symptoms. DAO was positively correlated with depression and negatively correlated with QOL in IBD patients. ROC curves revealed that DAO was independently associated with psychological symptoms and clinical activity in patients with IBD. Additionally, logistic regression analysis revealed that each 1-ng/mL increase in DAO levels was significantly associated with an increased risk of psychological symptoms in IBD patients (OR: 1.019, 95%CI: 1.002-1.037). These results highlight the potential of DAO as a novel biomarker for both depression and disease activity in IBD patients.
This study indicates that DAO may be associated with depression and disease activity in IBD patients; however, prospective studies are required to validate its causal relationship.
Core Tip: Few studies have explored the association between markers of intestinal barrier dysfunction and psychological symptoms in patients with inflammatory bowel disease (IBD). Our study revealed that serum diamine oxidase (DAO) levels were significantly elevated in IBD patients with moderate-to-severe psychological symptoms as compared to those with no or mild psychological symptoms. Furthermore, correlation analysis indicated that DAO was positively associated with depression and negatively associated with quality of life in IBD patients. Additionally, receiver operating characteristic curves confirmed that DAO is associated with clinical disease activity in patients with IBD. This study suggests the potential of DAO as a novel biomarker for predicting psychological symptoms and disease activity in IBD.