Druliner, B. R. | bioRxiv Science

bioRxiv2026

Maladaptive Piezo1 Mechanotransduction Drives Smooth Muscle Aging in the Gut

Age-related gastrointestinal dysfunction is common, but the mechanisms of aging-associated smooth muscle failure remain unclear. We show that aging in mice slows whole gut and colonic transit, increases regional stiffness, and reduces smooth muscle contractility. Inducible smooth muscle cell (SMC) specific deletion of Piezo1 preserved youthful transit and force generation, whereas Piezo1 activation in young mice phenocopied aging-associated transit delay. Single cell transcriptomics, RNA velocity, stiffness-controlled cell and tissue cultures, and pharmacologic studies revealed that Piezo1 couples increased stiffness to Ca2+, calcineurin, NFAT signaling, loss of contractile gene programs, leading to age-related contractile loss and contractile to synthetic SMC remodeling and gut wall stiffening. Human intestinal SMCs supported conservation of this pathway, and PIEZO1 gain of function carriers showed a trend toward delayed colonic transit. Thus, maladaptive SMC Piezo1 mechanotransduction is a targetable mechanism of aging-associated gut dysmotility.

physiology↗

bioRxiv2025

Intestinal Stem Cells Retain an Epigenetic Memory of Prior Inflammation

Intestinal epithelial damage and impaired repair are hallmarks of ulcerative colitis (UC), even after inflammation resolves. Intestinal stem cells (ISCs) can retain stable epigenetic changes after inflammation, highlighting the potential for long-lived epithelial memory in the gut. Inflammatory injury in barrier tissues induces epigenetic memory in epithelial stem cells, and the tendency of UC to relapse at previously inflamed sites led us to hypothesize that ISCs from IBD patients acquire lasting memory of prior inflammation. To test this, we derived colonic organoids from inflamed and uninflamed regions of the same UC patients and propagated in long-term culture. Chromatin profiling revealed 2,252 accessible regions unique to prior-inflamed (PI) organoids, associated with stress response, repair, and inflammatory genes. Although these regions remained accessible, [~]95% of associated genes were not upregulated in PI organoids, indicating a primed state. Upon inflammatory or injury re-challenge, PI organoids exhibited heightened transcriptional responses and accelerated wound closure, despite reduced clonogenicity and impaired barrier function, indicating a retained inflammatory memory program. Our findings demonstrate that human ISCs retain a chromatin-based memory of inflammation that persists in the absence of immune cues and shapes future responses to injury. While this may support epithelial adaptation to secondary insults, it may predispose tissue to relapse in patients with UC.

molecular biology↗