NFAT5 dictates crosstalk between intestinal epithelial regenerative capacity and microbiota in murine colitis models
Se-Hyeon Park, Dae Hee Cheon, Yu-Mi Kim, Yeji Choi, Yong-Joon Cho, Bong-Ki Hong, Sang-Hyun Cho, Mi-Na Kweon, Hyug Moo Kwon, Eugene B. Chang, Donghyun Kim, Wan-Uk Kim
Se-Hyeon Park, Dae Hee Cheon, Yu-Mi Kim, Yeji Choi, Yong-Joon Cho, Bong-Ki Hong, Sang-Hyun Cho, Mi-Na Kweon, Hyug Moo Kwon, Eugene B. Chang, Donghyun Kim, Wan-Uk Kim
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Research Article Gastroenterology Immunology

NFAT5 dictates crosstalk between intestinal epithelial regenerative capacity and microbiota in murine colitis models

Abstract

Hypertonic and hyperosmolar stimuli frequently pose challenges to the intestinal tract. Therefore, a resilient epithelial barrier is essential for maintaining gut homeostasis in the presence of osmotic perturbations. Nuclear factor of activated T cells 5 (NFAT5), an osmosensitive transcription factor, primarily maintains cellular homeostasis under hypertonic conditions. However, the osmoprotective role of NFAT5 in enterocyte homeostasis is poorly understood. Here, we demonstrate that NFAT5 was critical for the survival and proliferation of intestinal epithelial cells (IECs) and that its deficiency accelerated chemically induced or spontaneous colitis in mice. Mechanistically, NFAT5 promoted the survival of IECs and the renewal of intestinal stem cells, thereby regulating the production of mucus and antimicrobial compounds, including RegIII and lysozyme, which consequently shape the gut microbial composition to prevent colitis. Transcriptome analysis identified HSP70 as a key downstream target of NFAT5 in epithelial regeneration. Loss- and gain-of-function experiments involving HSP70 revealed that NFAT5 mitigated experimental colitis through IEC Hsp70, which protected stem cells from inflammation-induced injury and maintained barrier function. In conclusion, our study demonstrates what we believe to be a previously unknown role for NFAT5 in dictating the crosstalk between intestinal stem cells and the microbiota, underscoring the importance of the NFAT5/HSP70 axis in maintaining epithelial regeneration related to gut barrier function, balancing microbial composition, and subsequently preventing colitis progression.

Authors

Se-Hyeon Park, Dae Hee Cheon, Yu-Mi Kim, Yeji Choi, Yong-Joon Cho, Bong-Ki Hong, Sang-Hyun Cho, Mi-Na Kweon, Hyug Moo Kwon, Eugene B. Chang, Donghyun Kim, Wan-Uk Kim

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Figure 4

Gut permeability and the expression of tight-junction molecules are modulated by Nfat5 deficiency and exposure to feces from Nfat5+/– mice.

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Gut permeability and the expression of tight-junction molecules are modu...
(A and B) Results of a gut permeability assay in Nfat5+/+ and Nfat5+/– mice housed separately (A) or cohoused (B). Mice were fasted for 12 hours, after which FITC-dextran (average molecular weight ≈4 kDa) was administered to the mice via oral gavage. Four hours later, fluorescence signals were measured in sera of the mice. (C and D) Relative expression levels of Tjp1 (ZO-1) mRNA and protein in small IECs from separately housed Nfat5+/+ and Nfat5+/– mice were determined by qRT-PCR and immunoblotting, respectively. Gapdh (C) and β-actin (D) were used as internal controls, respectively. (E) ZO-1 expression in the ileal tissues of separately housed Nfat5+/+ and Nfat5+/– mice was assessed by immunostaining with anti-ZO-1 (green) and anti–E-cadherin (red) antibodies. Nuclei were counterstained with DAPI (blue). Representative merged images and corresponding graphs are shown. Scale bars: 20 μm. (F and G) Relative Tjp1 (ZO-1) mRNA and protein expression levels in small IECs of cohoused Nfat5+/+ and Nfat5+/– mice by qRT-PCR and immunoblotting, respectively. Gapdh (F) and β-actin (G) were used as internal controls for normalization, respectively. (H–J) Recipient mice were pretreated 5 times, every other day with an antibiotic cocktail for 3 weeks and transplanted with feces obtained from donor mice (shown in indices). A gut permeability assay was performed on Nfat5+/+ and Nfat5+/– recipient mice transplanted with fecal microbiota derived from Nfat5+/– (H) and Nfat5+/+ donors (I). Fluorescence signals were measured in their sera after oral gavage of FITC-dextran. The expression of ZO-1 in the ileal tissues of Nfat5+/– mice, following fecal transplantation from either Nfat5+/+ or Nfat5+/– donors, was assessed by immunostaining using anti–ZO-1 (green) and anti–E-cadherin (red) antibodies (J). Scale bars: 20 μm. Nuclei were counterstained with DAPI (blue). Representative merged images and corresponding graphs are shown. Each dot represents an individual mouse, and the means are displayed as lines (A–J). *P < 0.05, **P < 0.01, and ***P < 0.001, by Mann-Whitney U test. Data shown in A–J are representative of 2 independent experiments.