Microglia in neuroimmunopharmacology and drug addiction

• Published in: Molecular psychiatry Vol. 29; no. 6; pp. 1912 - 1924
• Main Authors: Li, Hongyuan, Watkins, Linda R., Wang, Xiaohui
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-06-2024; Nature Publishing Group
• Subjects: 13/21; 631/378; 64/60; 692/699/476/5; 96/95; 96/98; Addictions; Animals; Behavioral Sciences; Biological Psychology; Brain - drug effects; Brain - metabolism; Cytokines - metabolism; Drug abuse; Drug addiction; Humans; Immune system; Inflammation; Medicine; Medicine & Public Health; Microglia; Microglia - drug effects; Microglia - metabolism; Neuroimmunomodulation - drug effects; Neuroimmunomodulation - physiology; Neuroinflammatory Diseases - drug therapy; Neuromodulation; Neurosciences; Perspective; Pharmacotherapy; Psychiatry; Public health; Substance-Related Disorders
• ISSN: 1359-4184; 1476-5578; 1476-5578
• DOI: 10.1038/s41380-024-02443-6

Drug addiction is a chronic and debilitating disease that is considered a global health problem. Various cell types in the brain are involved in the progression of drug addiction. Recently, the xenobiotic hypothesis has been proposed, which frames substances of abuse as exogenous molecules that are responded to by the immune system as foreign “invaders”, thus triggering protective inflammatory responses. An emerging body of literature reveals that microglia, the primary resident immune cells in the brain, play an important role in the progression of addiction. Repeated cycles of drug administration cause a progressive, persistent induction of neuroinflammation by releasing microglial proinflammatory cytokines and their metabolic products. This contributes to drug addiction via modulation of neuronal function. In this review, we focus on the role of microglia in the etiology of drug addiction. Then, we discuss the dynamic states of microglia and the correlative and causal evidence linking microglia to drug addiction. Finally, possible mechanisms of how microglia sense drug-related stimuli and modulate the addiction state and how microglia-targeted anti-inflammation therapies affect addiction are reviewed. Understanding the role of microglia in drug addiction may help develop new treatment strategies to fight this devastating societal challenge.