SM22α Deletion Contributes to Neurocognitive Impairment in Mice through Modulating Vascular Smooth Muscle Cell Phenotypes.

Considerable evidence now indicates that cognitive impairment is primarily a vascular disorder. The depletion of smooth muscle 22 alpha (SM22α) contributes to vascular smooth muscle cells (VSMCs) switching from contractile to synthetic and proinflammatory phenotypes in the context of inflammation. However, the role of VSMCs in the pathogenesis of cognitive impairment remains undetermined. Herein, we showed a possible link between VSMC phenotypic switching and neurodegenerative diseases via the integration of multi-omics data. SM22α knockout (Sm22α-/-) mice exhibited obvious cognitive impairment and cerebral pathological changes, which were visibly ameliorated by the administration of AAV-SM22α. Finally, we confirmed that SM22α disruption promotes the expression of SRY-related HMG-box gene 10 (Sox10) in VSMCs, thereby aggravating the systemic vascular inflammatory response and ultimately leading to cognitive impairment in the brain. Therefore, this study supports the idea of VSMCs and SM22α as promising therapeutic targets in cognitive impairment to improve memory and cognitive decline.

Sox10 escalates vascular inflammation by mediating vascular smooth muscle cell transdifferentiation and pyroptosis in neointimal hyperplasia.

Vascular smooth muscle cells (VSMCs) can transdifferentiate into macrophage-like cells in the context of sustained inflammatory injury, which drives vascular hyperplasia and atherosclerotic complications. Using single-cell RNA sequencing, we identify that macrophage-like VSMCs are the key cell population in mouse neointimal hyperplasia. Sex-determining region Y (SRY)-related HMG-box gene 10 (Sox10) upregulation is associated with macrophage-like VSMC accumulation and pyroptosis in vitro and in the neointimal hyperplasia of mice. Tumor necrosis factor α (TNF-α)-induced Sox10 lactylation in a phosphorylation-dependent manner by PI3K/AKT signaling drives transcriptional programs of VSMC transdifferentiation, contributing to pyroptosis. The regulator of G protein signaling 5 (RGS5) interacts with AKT and blocks PI3K/AKT signaling and Sox10 phosphorylation at S24. Sox10 silencing mitigates vascular inflammation and forestalls neointimal hyperplasia in RGS5 knockout mice. Collectively, this study shows that Sox10 is a regulator of vascular inflammation and a potential control point in inflammation-related vascular disease.