I-FABP, Citrulline, and Liver Dysfunction Markers in Depressed Patients

Overview

This cross-sectional study investigated associations between intestinal dysfunction biomarkers (I-FABP, citrulline) and non-invasive liver dysfunction indices in patients with depressive disorders (DD). Findings suggest that altered gut barrier function correlates with hepatic steatosis and fibrosis markers, particularly in the presence of metabolic syndrome components.

Background

Depressive disorders and metabolic diseases are increasingly prevalent and may share pathophysiological mechanisms involving the gut-liver-brain axis (GLBA). Disruption of intestinal barrier integrity can lead to bacterial translocation, chronic liver inflammation, and subsequent hepatic steatosis and fibrosis. Biomarkers such as citrulline and I-FABP reflect intestinal epithelial health, while non-invasive hepatic indices (ALT/AST ratio, FSI, HSI, APRI, FIB-4) assess liver function and fibrosis risk. Understanding their interplay in depression may reveal novel insights into comorbid metabolic and hepatic dysfunction.

Data Highlights

The study enrolled 116 patients with depressive disorders, assessing serum levels of I-FABP and citrulline alongside liver indices including ALT/AST ratio, Framingham Steatosis Index (FSI), Hepatic Steatosis Index (HSI), AST to Platelet Ratio Index (APRI), and Fibrosis-4 (FIB-4). Metabolic syndrome components and psychometric scores were also recorded to evaluate their influence on these biomarkers.

Key Findings

• Serum citrulline levels serve as a biomarker of small intestine enterocyte mass, with reduced levels indicating gut dysfunction in depressed patients.
• I-FABP concentrations increase in response to enterocyte damage, reflecting intestinal permeability issues.
• Non-invasive hepatic indices (FSI, HSI, APRI, FIB-4) correlate with biomarkers of intestinal dysfunction, suggesting a link between gut barrier integrity and liver abnormalities in depression.
• Metabolic syndrome components exacerbate associations between intestinal biomarkers and liver dysfunction indices.
• These biomarkers collectively may indicate increased cardiovascular risk in patients with depression and metabolic comorbidities.

Clinical Implications

Clinicians should consider evaluating intestinal barrier function markers alongside non-invasive liver indices in patients with depressive disorders, especially those with metabolic syndrome. This integrated approach may facilitate early detection of hepatic dysfunction and guide interventions targeting the gut-liver-brain axis to mitigate progression of liver disease and cardiovascular risk.

Conclusion

The study highlights significant associations between intestinal dysfunction biomarkers and non-invasive liver dysfunction indices in depressed patients, underscoring the importance of the gut-liver-brain axis in the pathophysiology of depression with metabolic comorbidities. These findings support further research into targeted therapies addressing gut and liver health in this population.

References

1. PRO-DEMET Trial (NCT04756544) -- Probiotic Supplementation in Depression and Metabolic Syndrome
2. Montgomery-Åsberg Depression Rating Scale (MADRS) -- Depression Severity Assessment
3. Polish 2022 Metabolic Syndrome Definition -- Diagnostic Criteria