Connexin 43: An Interface Connecting Neuroinflammation to Depression

Major depressive disorder (MDD) is a leading chronic mental illness worldwide, characterized by anhedonia, pessimism and even suicidal thoughts. Connexin 43 (Cx43), mainly distributed in astrocytes of the brain, is by far the most widely and ubiquitously expressed connexin in almost all vital organs. Cx43 forms gap junction channels in the brain, which mediate energy exchange and effectively maintain physiological homeostasis. Increasing evidence suggests the crucial role of Cx43 in the pathogenesis of MDD. Neuroinflammation is one of the most common pathological features of the central nervous system dysfunctions. Inflammatory factors are abnormally elevated in patients with depression and are closely related to nearly all links of depression. After activating the inflammatory pathway in the brain, the release and uptake of glutamate and adenosine triphosphate, through Cx43 in the synaptic cleft, would be affected. In this review, we have summarized the association between Cx43 and neuroinflammation, the cornerstones linking inflammation and depression, and Cx43 abnormalities in depression. We also discuss the significant association of Cx43 in inflammation and depression, which will help to explore new antidepressant drug targets.

Automated summary

English Summary: This review article explores the importance of Connexin 43 (Cx43) in the pathogenesis of major depressive disorder (MDD), specifically in relation to neuroinflammation. Neuroinflammation is a common pathological feature of central nervous system dysfunctions, with increased inflammatory factors observed in MDD patients, closely associated with various aspects of depression. Activation of the inflammatory pathway in the brain affects the release and uptake of neurotransmitters glutamate and adenosine triphosphate through Cx43 in the synaptic cleft. This research contributes to the exploration of new antidepressant drug targets.