TY - JOUR

T1 - Intestinal epithelial Suppressor of Cytokine Signaling (SOCS) 3 enhances microbial induced inflammatory TNFα, contributing to epithelial barrier dysfunction

AU - Thagia, Imtiyaz

AU - Shaw, Elisabeth J.

AU - Smith, Emily

AU - Else, Kathryn J.

AU - Rigby, Rachael Jane

N1 - Copyright © 2015 the American Physiological Society Licensed under Creative Commons Attribution CC-BY 3.0: © the American Physiological Society.

PY - 2015/1/1

Y1 - 2015/1/1

N2 - A single layer of intestinal epithelial cells (IEC) lines the entire GI tract and provides the first line of defence and barrier against an abundance of microbial stimuli. IEC homeostasis and repair are mediated through microbe-sensing Toll-like receptor (TLR)-induced inflammatory pathways. Increasing evidence supports a role of suppressor of cytokine signaling 3 (SOCS3) as a modulator of IEC turnover, balancing controlled repair and replenishment with excessive IEC proliferation predisposing to dysplasia and cancer. Our data indicate that SOCS3 can limit microbial-induced epithelial repair, promote TNFα, possibly through limiting TNFR2 expression in intestinal epithelial cells (IEC). Activation of TLR5 signalling pathways, compared with other TLR, increase TNFα mRNA in a dose dependent manner and SOCS3 enhances TLR5-induced TNFα. We also show that flagellin promotes transcription of TNFR2 and that SOCS3 may limit this expression, presenting a mechanism of SOCS3 action. Our data also supports the role of microbial ligands in epithelial wound healing and suggests that a functional consequence of increased TNFα is reduced wound healing. These results provide further evidence to support the regulatory role of epithelial SOCS3 in intestinal health and suggest that the increased expression of SOCS3 observed in IBD may serve to perpetuate 'inflammation' by promoting TNFα production and limiting epithelial repair in response to commensal microflora.

AB - A single layer of intestinal epithelial cells (IEC) lines the entire GI tract and provides the first line of defence and barrier against an abundance of microbial stimuli. IEC homeostasis and repair are mediated through microbe-sensing Toll-like receptor (TLR)-induced inflammatory pathways. Increasing evidence supports a role of suppressor of cytokine signaling 3 (SOCS3) as a modulator of IEC turnover, balancing controlled repair and replenishment with excessive IEC proliferation predisposing to dysplasia and cancer. Our data indicate that SOCS3 can limit microbial-induced epithelial repair, promote TNFα, possibly through limiting TNFR2 expression in intestinal epithelial cells (IEC). Activation of TLR5 signalling pathways, compared with other TLR, increase TNFα mRNA in a dose dependent manner and SOCS3 enhances TLR5-induced TNFα. We also show that flagellin promotes transcription of TNFR2 and that SOCS3 may limit this expression, presenting a mechanism of SOCS3 action. Our data also supports the role of microbial ligands in epithelial wound healing and suggests that a functional consequence of increased TNFα is reduced wound healing. These results provide further evidence to support the regulatory role of epithelial SOCS3 in intestinal health and suggest that the increased expression of SOCS3 observed in IBD may serve to perpetuate 'inflammation' by promoting TNFα production and limiting epithelial repair in response to commensal microflora.

U2 - 10.1152/ajpgi.00214.2014

DO - 10.1152/ajpgi.00214.2014

M3 - Journal article

C2 - 25377316

VL - 308

SP - G25-G31

JO - American Journal of Physiology-Gastrointestinal and Liver Physiology

JF - American Journal of Physiology-Gastrointestinal and Liver Physiology

SN - 0193-1857

IS - 1

ER -