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bioRxiv · 10.1101/2024.03.14.584870

Novel, postnatal manifestation of an epidermal barrier defect in a mouse model of isolated sulfite oxidase deficiency

Johannes, L.·Ruebsam, M.·Loehr, J.·Ding, X.·Eming, S.·Niessen, C. M.·Schwarz, G.
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Abstract

Sulfite oxidase deficiency is a rare inborn error in metabolism leading to early childhood death due to rapidly progressing neurodegeneration. A new mouse model of sulfite oxidase deficiency carrying a homozygous deletion in the Suox gene resembles the human pathology in terms of neonatal death and elevation of sulfite and thiosulfate in plasma and urine, respectively. Homozygous Suox-/- mice are initially born healthy, display growth retardation starting at postnatal day 4 and die in average at day 9.6. Here we report that Suox-/- mice develop dry and scaly skin early postnatally, showing that sulfite oxidase is essential to maintain a functional skin barrier after birth. At postnatal day 5 Suox-/- mice develop altered epidermal morphology and dysregulated early and late keratinocyte differentiation accompanied by increased stress response. We propose a sulfite-induced cleavage of disulfide bonds in key epidermal proteins essential for a functional barrier.

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Johannes, L., Ruebsam, M., Loehr, J., Ding, X., Eming, S., Niessen, C. M., Schwarz, G.. 2024-03-19. Novel, postnatal manifestation of an epidermal barrier defect in a mouse model of isolated sulfite oxidase deficiency. https://doi.org/10.1101/2024.03.14.584870

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