The role of the gut microbiome in the pathogenesis of Attention-Deficit/Hyperactivity Disorder

Abstract

The gut microbiome is a crucial component that regulates numerous bodily functions, including inter-organ communication with the central nervous system (CNS), known as the ‘microbiome–gut–brain axis.’ Disruptions in microbiome composition, manifesting as dysbiosis, are identified in ADHD and have recently been considered a key pathophysiological factor. Structural and functional changes in the microbiome during ADHD may underlie systemic inflammation and neuronal dysfunction, highlighting its importance in the etiopathogenesis of this disorder. Early childhood and adolescence are particularly vulnerable periods in this context, as they involve the active maturation of both the microbiome and neural structures. This article discusses the contribution of five major bacterial phyla associated with the mechanisms of systemic inflammation in ADHD: Actinomycetota, Bacillota, Bacteroidota, Pseudomonadota , and Verrucomicrobiota . Future research is encouraged to focus on short-chain fatty acids and lipopolysaccharide-binding proteins as potential biomarkers of dysbiosis-induced systemic inflammation.»