Enteroendocrine cells: a review of their role in brain–gut communication

<jats:title>Abstract</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>Specialized endoderm‐derived epithelial cells, that is, enteroendocrine cells (<jats:styled-content style="fixed-case">EEC</jats:styled-content>s), are widely distributed throughout the gastrointestinal (<jats:styled-content style="fixed-case">GI</jats:styled-content>) tract. Enteroendocrine cells form the largest endocrine organ in the body and play a key role in the control of <jats:styled-content style="fixed-case">GI</jats:styled-content> secretion and motility, the regulation of food intake, postprandial glucose levels and metabolism. <jats:styled-content style="fixed-case">EEC</jats:styled-content>s sense luminal content and release signaling molecules that can enter the circulation to act as classic hormones on distant targets, act locally on neighboring cells and on distinct neuronal pathways including enteric and extrinsic neurons. Recent studies have shed light on <jats:styled-content style="fixed-case">EEC</jats:styled-content> sensory transmission by showing direct connections between <jats:styled-content style="fixed-case">EEC</jats:styled-content>s and the nervous system via axon‐like processes that form a well‐defined neuroepithelial circuits through which <jats:styled-content style="fixed-case">EEC</jats:styled-content>s can directly communicate with the neurons innervating the <jats:styled-content style="fixed-case">GI</jats:styled-content> tract to initiate appropriate functional responses.</jats:p></jats:sec><jats:sec><jats:title>Purpose</jats:title><jats:p>This review will highlight the role played by the <jats:styled-content style="fixed-case">EEC</jats:styled-content>s in the complex and integrated sensory information responses, and discuss the new findings regarding <jats:styled-content style="fixed-case">EEC</jats:styled-content>s in the brain–gut axis bidirectional communication.</jats:p></jats:sec>