Zinc-alpha-2-glycoprotein Levels In Patients with Major Depressive Disorder and Relationship Between Obesity

Abstract: Major depressive disorder (MDD) is the most common mood disorder, characterized by various mental, physical, and cognitive symptoms. Diagnosis is primarily based on structured clinical interviews, making the process subjective. The discovery of new biomarkers may enhance the accuracy of depression diagnoses. Zinc alpha-2-glycoprotein (ZAG) is a glycoprotein weighing 41-43 kDa, found in various cells and tissues, and secreted into many body fluids. Objective: This study aims to determine the potential of ZAG in the differential diagnosis of MDD and to investigate the relationship between MDD, ZAG, and obesity. The study included 44 patients diagnosed with MDD at the Psychiatry Department of Balıkesir University and 40 healthy volunteers. Results: The median ZAG levels for the control and patient groups were 69.0 (19-150) µg/ml and 32.4 (0.5-150) µg/ml, respectively. The difference between the two groups was statistically significant (P=0.020). However, regression analysis, accounting for age, indicated that this difference was not statistically significant (Pdüz=0.059). Additionally, no statistically significant correlation was observed between ZAG levels and body mass index (BMI) (P=0.063). Conclusion: This study demonstrates that ZAG levels are lower in patients with MDD compared to the control group and may be associated with the severity of depression. The findings highlight the need for further studies investigating the potential role of ZAG as a biomarker for depression. Keywords: Zinc alpha-2-glycoprotein, major depressive disorder, obesity.