Layilin is critical for mediating hyaluronan 35 kDa-induced intestinal epithelial tight junction protein ZO-1 in vitro and in vivo

Abstract

Tight junction proteins are critical in maintaining homeostatic intestinal permeability. Multiple intestinal inflammatory diseases are correlated with reduced expression of tight junction proteins. We have recently reported that oral treatment of mice with Hyaluronan 35kDa (HA35) increases colonic expression of tight junction protein zonula occludens-1 (ZO-1). Here, we investigate whether HA35 treatment enhances ZO-1 expression by direct interaction with intestinal epithelium in vitro and have identified the HA receptor responsible for HA35-mediated ZO-1 induction in colonic epithelium in vitro and in vivo. Our results reveal that HA35 treatment increases ZO-1 expression in mouse intestinal epithelial organoids, while large HA 2000kDa is not internalized into the cells. Our immunofluorescence data indicate that layilin, but neither toll-like receptor-4 (TLR-4) nor CD44, mediate the HA35-induced ZO-1 expression in colonic epithelium in vitro and in vivo. Additionally, using layilin null mice we have determined that layilin mediates HA35 induction of ZO-1 in healthy mice and during dextran sulfate sodium (DSS)-induced colitis. Furthermore, we find that while ZO-1 expression levels are reduced, layilin expression levels are equivalent in inflammatory bowel disease (IBD) patients and non-IBD controls. Together, our data suggest that layilin is an important HA receptor, that mediates the effect of oral HA35 treatment on intestinal epithelium. HA35 holds promise as a simple dietary supplement to strengthen gut barrier defense.

Specifically Sized Hyaluronan (35 kDa) Prevents Ethanol‐Induced Disruption of Epithelial Tight Junctions Through a layilin‐Dependent Mechanism in Caco‐2 Cells

“…This protective effect of HA35 on tight junction integrity in the cultured Caco‐2 cells indicates that the protective effect of HA35 in a murine model of short‐term EtOH exposure is likely due, at least in part, to a direct effect on the intestinal epithelium. A direct protective effect of HA35 with intestinal epithelial cells is consistent with the direct effects of HA35 on the expression of tight junction proteins in a murine intestinal organoid system (Kim et al., ). However, HA35 may also be acting to protect the gut from EtOH in vivo via indirect effects in suppressing intestinal inflammation (Chen et al., ), as HA35 treatment reduces TLR4‐mediated signaling in hepatic macrophages (Saikia et al., ).…”

“…Layilin is highly expressed in epithelial tissue and integrates intracellular signaling mechanisms involved in the maintenance of tight junctions (Adachi et al., ; Arpin et al., ; Bono et al., ). Further, HA35‐induced increases in the expression of the tight junction protein ZO‐1 are mediated via layilin both in vivo and in intestinal organoid cultures in vitro (Kim et al., ). Interestingly, EtOH exposure disrupted tight junctions independently of changes in the total expression of ZO‐1 and occludin (Fig.…”

Lipopolysaccharide-Induced Chorioamnionitis Induces Fetal Intestinal Injury and Affects Gut Colonization in Rats

“…The intestinal epithelium not only separates internal organs from the harmful environment of gut lumen, but also protects against incursion of toxins and foreign microorganisms [25,26]. ZO-1 is one of the main transmembrane proteins that compose the tight junction of the intestinal epithelium,and plays an important role in maintaining the integrity of the intestinal mucosal barrier and intestinal permeability [27]. Disruption of the intestinal barrier is associated with downregulation of tight junction proteins and has been observed in many intestinal diseases such as NEC [28,29].…”

Ruscogenin Alleviates Intestinal Bleeding and Blood Flow Induced by Dasatinib through ROCK/MLC Pathway

“…The destruction of connexin will affect the integrity of intestinal blood vessels, increase the permeability of blood vessels, and cause leakage of blood vessels. Therefore, connexin plays a signi cant role in stabilizing intestinal permeability.Tight junctions are essential for regulating intestinal permeability [37][38] . The tight junction proteins in EC include ZO-1, claudin-5, occludin and several JAMs.…”