Serum NOX1 and Raftlin as new potential biomarkers of Major Depressive Disorder: A study in treatment-naive first episode patients

Abstract

Introduction: Biological factors are known to be important in understanding the pathogenesis of Major Depressive Disorder (MDD). Oxidative stress and neuroinflammation pathways are likely to play a critical role here. Methods: We undertook a study to investigate two novel biomarkers - serum NADPH oxidase 1 (NOX1) and Raftlin levels - in treatment-naive, smoking-free first episode patients with MDD compared to healthy controls (HCs) matched for age, sex and body mass index. Results: We found increased NOX1 and Raftlin levels in MDD patients compared to HCs. Both parameters showed very good diagnostic performance in the MDD group. In addition, we found a significant positive correlation between depression severity (HAM–D) scores and both biomarker levels in the patient group. Conclusion: To the best of our knowledge, this is the first human study to evaluate serum NOX1 and Raftlin levels in depression. NOX1, an important source of reactive oxygen species (ROS), and Raftlin, which may play a role in the inflammatory process, represent novel potential biomarkers of MDD. These findings support the implication of oxidative stress and inflammatory processes in patients with MDD, and indicate that the deteriorated ROS-antioxidant balance can be regulated via NOX1 in patients with depression.