CH-223191

Objective: Intestinal inflammatory diseases significantly affect animal health, primarily by disrupting intestinal barrier function. Indole-3-carboxaldehyde (IAld), a key metabolite of tryptophan derived from gut microbiota, exhibits protective properties against intestinal inflammatory diseases. The regulatory mechanism by which IAld modulates intestinal barrier function requires further investigation.Methods: An intestinal epithelial cell injury model was established by tumor necrosis factor-alpha (TNF-α) stimulation, alongside a mouse colitis model induced by dextran sulfate sodium (DSS) administration. Intestinal barrier function was assessed by immunoblotting, immunofluorescence, in vitro permeability assays, and histopathological analysis. Mitochondrial integrity and function were evaluated using JC-1 staining and transmission electron microscopy. Additionally, key components of the aryl hydrocarbon receptor (AhR)/AMP-activated protein kinase (AMPK) signaling pathway were analyzed using immunoblotting, immunofluorescence, and immunoprecipitation techniques.Results: Our findings demonstrate that IAld treatment significantly enhanced tight junction protein expression in intestinal epithelial cells and effectively attenuated TNF-α-induced intestinal barrier injury. IAld activated cellular AMPK signaling, promoting autophagy, maintaining mitochondrial homeostasis, and ultimately improving intestinal barrier function. Importantly, the activation of AMPK signaling by IAld was found to be dependent on the AhR, as evidenced by the AhR-specific inhibitor CH-223191, which abolished both IAld-induced AMPK activation and enhancement of intestinal barrier integrity. Furthermore, in vivo< experiments confirmed that IAld ameliorated intestinal barrier dysfunction and mitochondrial damage in DSS-induced colitis mice, whereas pharmacological inhibition of AMPK largely abrogated these protective effects.Conclusion: Our findings demonstrate that IAld effectively preserves intestinal barrier integrity, highlighting its potential application in the treatment of intestinal inflammatory diseases in both animals and humans.

Colorectal cancer (CRC) has always been a major concern for researchers due to its deadly nature. One of the microbial metabolites found in the gut is short-chain fatty acids (SCFAs), which have the ability to regulate the immune system and exert protective effects against CRC. In this study, we investigated the effects of SCFAs on the expression of the CYP1A1 gene in Caco-2 cells at varying concentrations. The Caco-2 cell line and HDF control cell line were treated with three concentrations (7.5, 15, and 30 mM) of NaA(sodium acetate), NaB(sodium butyrate), and NaP(sodium propionate) for three different time periods (24, 48, and 72 h). Additionally, two concentrations (2.5 and 10 μM) of CH223191 (an AhR gene antagonist) alone and a concentration of 10 μM of CH223191 in combination with the mentioned concentrations of NaA, NaB and NaP were applied to the cells for 48 h. The gene expression of CYP1A1 was examined using Real-time PCR. The expression of the CYP1A1 gene increased with concentrations of NaA and NaB at all time points, and with 30 mM of NaP at 24 h (p < 0.05). However, increasing the concentration of NaB and NaP led to decreased expression of the CYP1A1 gene. These findings suggest the potential use of SCFAs as epigenetic drugs for the prevention and treatment of CRC.