Role of Interleukin-6 in Depressive Disorder

• Published in: International journal of molecular sciences 2020-03, Vol.21 (6), p.2194
• Main Authors: Ting, Emily Yi-Chih, Yang, Albert C, Tsai, Shih-Jen
• Format: Article
• Language: English
• Subjects: Animals; Antidepressants; Caregivers; Cytokines; Depressive Disorder, Major - etiology; Depressive Disorder, Major - genetics; Depressive Disorder, Major - metabolism; Depressive Disorder, Major - pathology; Humans; Hypothalamic-pituitary-adrenal axis; Hypothalamo-Hypophyseal System - metabolism; Hypothalamo-Hypophyseal System - pathology; Hypothalamus; Immune system; Inflammation; Inflammation - complications; Inflammation - genetics; Inflammation - metabolism; Inflammation - pathology; Interleukin 6; Interleukin-6 - analysis; Interleukin-6 - genetics; Interleukin-6 - metabolism; Mental depression; Neurotransmitters; Pathogenesis; Patients; Physicians; Pituitary; Polymorphism, Genetic; Probiotics; Proteins; Quality of life; Review; Stress, Psychological - complications; Stress, Psychological - genetics; Stress, Psychological - metabolism; Stress, Psychological - pathology; Studies; Suicide
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms21062194

Major depressive disorder (MDD), which is a leading psychiatric illness across the world, severely affects quality of life and causes an increased incidence of suicide. Evidence from animal as well as clinical studies have indicated that increased peripheral or central cytokine interleukin-6 (IL-6) levels play an important role in stress reaction and depressive disorder, especially physical disorders comorbid with depression. Increased release of IL-6 in MDD has been found to be a factor associated with MDD prognosis and therapeutic response, and may affect a wide range of depressive symptomatology. However, study results of the genetic effects in MDD are controversial. Increased IL-6 activity may cause depression through activation of hypothalamic-pituitary-adrenal axis or influence of the neurotransmitter metabolism. The important role of neuroinflammation in MDD pathogenesis has created a new perspective that the combining of blood IL-6 and other depression-related cytokine levels may help to classify MDD biological subtypes, which may allow physicians to identify the optimal treatment for MDD patients. To modulate the IL-6 activity by IL-6-related agents, current antidepressive agents, herb medication, pre-/probiotics or non-pharmacological interventions may hold great promise for the MDD patients with inflammatory features.