Serum markers related to depression: A systematic review

Abstract

Depression has a multifactorial aetiology and is one of the most common neurological and psychiatric disorders that are associated with imbalance in certain inhibitory and excitatory neurotransmitters and impairment of the brain-derived neurotrophic factor (BDNF). This review study was conducted to investigate the effect of BDNF and neuromediators on the development and severity of depression. To conduct this systematic review, relevant publications that were published between 2000 and 2016 and were indexed in the PubMed, Google Scholar, Scopus and Web of Science databases were retrieved using the depression, serum markers, neurotransmitters, serotonin, BDNF, dopamine, glutamate and gamma amino-butyric acid search terms. A total of 89 articles were included in final analysis. Depression is associated with imbalance of certain neurotransmitters such as serotonin, dopamine, norepinephrine, melatonin and glutamate in the central nervous system and impairment of BDNF. Taken together, there is a significant relationship between depression and neuromediators, and the decrease and increase in these mediators plays a significant role in depression. Studies have also confirmed that the antidepressant effect of drugs and medicinal plants is essentially related to the serotonergic pathway, especially the 5-HT1A receptor, and drugs and medicinal herbs are likely to exert their antidepressant activity through altering dopaminergic and serotonergic systems.Journal of Medical and Biomedical Sciences (2017) 6(3), 30 - 42