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bioRxiv · 10.1101/2024.05.31.596805

Early life adversity promotes gastrointestinal dysfunction through a sex-dependent phenotypic switch in enteric glia

Abstract

Irritable bowel syndrome and related disorders of gut-brain interaction (DGBI) are common and exhibit a complex, poorly understood etiology that manifests as abnormal gut motility and pain. Risk factors such as biological sex, stressors during critical periods, and inflammation are thought to influence DGBI vulnerability by reprogramming gut-brain circuits, but the specific cells affected are unclear. Here, we used a model of early life stress to understand cellular mechanisms in the gut that produce DGBIs. Our findings identify enteric glia as a key cellular substrate in which stress and biological sex converge to dictate DGBI susceptibility. Enteric glia exhibit sexual dimorphism in genes and functions related to cellular communication, inflammation, and disease susceptibility. Experiencing early life stress has sex-specific effects on enteric glia that cause a phenotypic switch in male glia toward a phenotype normally observed in females. This phenotypic transformation is followed by physiological changes in the gut, mirroring those observed in DGBI in humans. These effects are mediated, in part, by alterations to glial prostaglandin and endocannabinoid signaling. Together, these data identify enteric glia as a cellular integration site through which DGBI risk factors produce changes in gut physiology and suggest that manipulating glial signaling may represent an attractive target for sex-specific therapeutic strategies in DGBIs.

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Gonzales, J. A., Dharshika, C., Mazhar, K., Morales-Soto, W., McClain, J. L., Moeser, A. J., Nault, R., Price, T. J., Gulbransen, B. D.. 2024-06-03. Early life adversity promotes gastrointestinal dysfunction through a sex-dependent phenotypic switch in enteric glia. https://doi.org/10.1101/2024.05.31.596805

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