Immunological Markers and Brain Derived Neurotrophic Factor in Major Depressive Disorder

Abstract

Background: Therapeutic approaches for major depressive disorder (MDD) are accessible; however, outcomes remain suboptimal, with approximately 50% of patients failing to achieve adequate response. The objective of this study was to evaluate immunological markers and brain-derived neurotrophic factor (BDNF) levels in a cohort of drug-free persons diagnosed with MDD, in a group of healthy first degree relatives of those cases diagnosed with MDD matched for sex and age, assessment of immunological markers and BDNF in a group of healthy control subjects matched for sex and age, comparison between 3 mentioned groups and assessment of correlation between severity of MDD and (immunological markers and BDNF) in patients’ group.

Methods: This cross sectional study involved 90 persons. All cases were selected by simple random sampling and randomized into 3 equal groups: Patients’ group with MDD diagnosed according to DSM-5 criteria, first degree relatives group; Healthy first degree relatives matched for sex and age and control group; Healthy control subjects matched for sex and age. All participants underwent general and neurological examinations and relevant investigations.

Results: TNF-α, IL6, hs-CRP, and IFN-γ were significant increase in cases had MDD than their first degree relatives and healthy control (P<0.001,<0.001,<0.001,<0.001). hs-CRP, IL6, TNF-α and IFN-γ were significantly higher in relatives group than healthy control group (P<0.001,<0.001,<0.001,<0.001). BDNF was significantly decrease in cases group than both 1th degree relatives group (P=0.001) and healthy control group. (P<0.001). Relatives group was significantly decrease in BDNF than healthy control group (P=0.011). 

Conclusions: MDD cases demonstrate a higher concentration of inflammatory markers (hs-CRP, IL6, TNF-α, IFN-γ) than 1th-degree relatives and control subjects. MDD cases exhibited reduced levels of BDNF than first-degree relatives and control subjects.