Sledziona, J. | bioRxiv Science

bioRxiv2025

Gasdermin C links nutrient and immune signaling to protist-induced type 2 immunity and intestinal repair

The Gasdermin family of proteins has recently been implicated in tissue repair and homeostasis through their effector function in type 2 immunity and pyroptosis. Yet the role of Gasdermin C proteins has not been fully characterized in the mammalian intestine, where environmental factors can influence epithelial regeneration and repair. Here we report that Gsdmc2-4 genes are regulated in a nutrient-dependent manner and are suppressed with aging. We uncover that commensal protists in the gut regulate Gsdmc2-4 expression through activation of type 2 immune responses. In intestinal organoid experiments, we find that STAT6 is necessary for Gsdmc2-4 induction in response to type 2 cytokines; however, basal expression of Gsdmc2-4 in vivo is only partially diminished in Stat6 knockout animals. Finally, in protist-colonized animals, loss of Gsdmc1-4 exacerbated mucosal erosion and inflammation in response to Dextran sodium sulfate (DSS) exposure, implicating these proteins in coordinating epithelial responses to injury.

physiology↗

bioRxiv2025

Stearoyl-CoA Desaturases regulate stem and progenitor cell metabolism and function in response to nutrient abundance

Dietary components and metabolites play a critical role in regulating intestinal stem and progenitor cell function and proliferation. Here we show that Stearoyl-CoA Desaturases (SCDs), which regulate intracellular saturated to monounsaturated fatty acids ratios, are induced in response to nutrient abundance, especially in the distal intestine, and regulate intestinal homeostasis. Genetic or pharmacological inhibition of SCDs altered lipid metabolism, increased ER stress, and reduced proliferative intestinal stem and progenitor cells in intestinal organoids. These effects were largely mitigated by oleic acid supplementation. Intestinal epithelium-specific deletion of Scd1 and Scd2 led to metabolic rewiring, leading to expansion of progenitor cell populations. DSS-induced epithelial damage revealed a dependence on SCD enzymes during regeneration, accelerating epithelial damage and inflammation in intestines lacking epithelial Scd1 and Scd2. These findings underscore key metabolic pathways and dependencies that enable intestinal stem and progenitor cells to adapt to nutrient fluctuations and support epithelial tissue regeneration following injury.

physiology↗