Association of Peroxiredoxin 1 and brain-derived neurotrophic factor serum levels with depression and anxiety symptoms in patients with irritable bowel syndrome

Background: Oxidative stress is considered a possible mechanism of irritable bowel syndrome (IBS) and depression. This study determined the possible association of serum peroxiredoxin 1 (PRDX1; a key antioxidant enzyme) and brain-derived neurotrophic factor (BDNF) with anxiety and depression symptoms in IBS patients. Methods: According to the Rome IV diagnostic criteria, 177 IBS patients from February 2019 to July 2019 were included. Serum levels of PRDX1, BDNF, and TNF alpha were detected by enzyme-linked immunosorbent assay. Levels of anxiety and depression were assessed with the Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS). Results: Compared with normal IBS patients, patients with anxiety and depression symptoms had significantly higher serum PRDX1 (p<0.001; p=0.002) and TNF alpha (p<0.001; p = 0.002) and significantly lower BDNF (p < 0.001; p = 0.002). Serum PRDX1 (r = 0.659, p < 0.001; r = 0.466, p < 0.001) and TNF alpha (r = 0.531, p < 0.001; r = 0.449, p < 0.001) were positively correlated with SAS and SDS, respectively, whereas BDNF was negatively correlated with SAS (r = 0.594, p < 0.001) and SDS (r = 0.534, p < 0.001). Multivariable regression analysis revealed that IBS severity, BDNF, and PRDX1 were significant predictors of anxiety. BDNF was also a significant predictor of depression. Conclusion: Elevated PRDX1 and decreased BDNF in serum may be closely related to psychological symptoms in IBS. Results of this study suggested that PRDX1 may be an important target for IBS treatment in fighting against intestinal and psychological symptoms.