A team of researchers from South Korea has discovered that Major Depressive Disorder (MDD) goes beyond an individual’s mental state, but rather starts from an imbalance in the body’s immune system, resulting in a complicated reaction from the brain and nervous system.
Spearheaded by Korea Advanced Institute of Science and Technology (KAIST) Graduate School of Medical Science and Engineering professor Han Jin-Ju, and professor Kim Yang- Sik from the Inha University School of Medicine, the team collaborated for an interdisciplinary, open-access, and peer-reviewed journal entitled, “Exploration of Novel Biomakers Through a Precision Medicine Approach Using Multi-Omics and Brain Organoids in Patients With Atypical Depression and Psychotic Symptoms.”
As reported by Korea JoongAng Daily, the study included the use of brain organoids, or “organic tissues made to resemble actual human organs,” alongside clinical data, white blood single-cell RNA sequencing and plasma proteomics, to pinpoint biomarkers in female patients diagnosed with MDD.
Patients also exhibited “atypical features,” “psychotic symptoms,” and impaired reality judgement. Symptoms include hypersomnia, excessive eating, auditory hallucinations, excessive guilt, and self-blame, said Technology News Network.
Based on their study, MDD patients with atypical symptoms increases the risk having bipolar disorder in later diagnosis. 40% were also classified as treatment-resistant depression, a disorder where symptoms do not improve after at least two different antidepressant medications.
Further research also indicated that MDD patients showed increased inflammation and immune dysregulation, reduced growth and distinct gene expression patterns, and higher levels of Doublecortin-Like Kinase 3 and Calcyon, proteins used in synaptic formation, and immune-related proteins such as Complement Component 5. This pointed to the fact that those with MDD showed signs of excessive brain and immune functions.
The team’s findings have unearthed a sign that depression is not just a “mood issue,” but it is connected to biological changes that is happening throughout the body. Genetic changes were discovered in immune cells of MDD patients, making inflammatory response occur stronger. This implies that the body’s immune system is in a “state of excessive activation,” and that this abnormality may influence the onset of depression – an overstep of the common concept that it is just a sad feeling, but a physical reaction from the overall mechanics of the human body.
