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bioRxiv · 10.1101/2022.12.20.521336

Recurrent hypoxia in a rat model of sleep apnea during pregnancy leads to microglia-dependent respiratory deficits and persistent neuroinflammation in adult male offspring

Abstract

Sleep apnea (SA) during pregnancy is detrimental to the health of the pregnancy and neonate, but little is known regarding long-lasting consequences of maternal SA during pregnancy on adult offspring. SA is characterized by repeated cessations in breathing during sleep, resulting in intermittent hypoxia (IH). We show that gestational IH (GIH) in rats reprograms the male fetal neuroimmune system toward enhanced inflammation in a region- and sex-specific manner, which persists into adulthood. Male GIH offspring also had deficits in the neural control of breathing, specifically in the ability to mount compensatory responses to central apnea, an effect that was rescued by a localized anti-inflammatory or microglial depletion. Female GIH offspring appeared unaffected. These results indicate that SA during pregnancy sex- and region-dependently skews offspring microglia toward a pro-inflammatory phenotype, which leads to long-lasting deficits in the capacity to elicit important forms of respiratory neuroplasticity in response to breathing instability. These studies contribute to the growing body of recent evidence indicating that SA during pregnancy may lead to sex-specific neurological deficits in offspring that persist into adulthood.

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BibTeXRIS

Mickelson, C. R., Ewald, A. C., Gumnit, M. G., Meza, A. L., Radcliff, A. B., Johnson, S. M., Ouellette, J. N., Kermath, B. A., Roopra, A., Cahill, M. E., Watters, J. J., Baker-Herman, T.. 2022-12-21. Recurrent hypoxia in a rat model of sleep apnea during pregnancy leads to microglia-dependent respiratory deficits and persistent neuroinflammation in adult male offspring. https://doi.org/10.1101/2022.12.20.521336

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