Protective effects of PX478 on gut barrier in a mouse model of ethanol and burn injury

• Type of Material: Article
• Authors: Niya L Morris, Loyola University of Chicago; Abigail R Cannon, Loyola University of Chicago; Xiaoling Li, Loyola University of Chicago; Mashkoor A Choudhry, Loyola University of Chicago
• Language: English
• Date: 2021-06-01
• Publisher: Oxford University Press
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: ©2020 Society for Leukocyte Biology
• Final Published Version (URL): http://dx.doi.org/10.1002/JLB.3A0820-323RR
• Title of Journal or Parent Work: Journal of Leukocyte Biology
• Volume: 109
• Issue: 6
• Start Page: 1121
• End Page: 1130
• Grant/Funding Information: This study was supported by the National Institutes of Health R01 AA015731, R01 GM128242, and T32 AA013527.
• Keywords: Male; MicroRNAs; Protective Agents; burn; microRNA; Biomarkers; intestine; Burns; Phenylpropionates; ethanol; Disease Susceptibility; hypoxia; Mice; Hypoxia-Inducible Factor 1, alpha Subunit; Argonaute Proteins; RNA, Ribosomal, 16S; Ethanol; Animals; Enzyme Inhibitors; Intestinal Mucosa; Mustard Compounds; Alcoholic Intoxication; RNA, Messenger

Abstract

Ethanol remains a confounder in postburn pathology, which is associated with an impaired intestinal barrier. Previously, we demonstrated that ethanol and burn injury reduce intestinal oxygen delivery (hypoxia) and alters microRNA (miR) expression in small intestinal epithelial cells. Hypoxia has been shown to influence expression of miRs and miR biogenesis components. Therefore, we examined whether hypoxia influences expression of miR biogenesis components (drosha, dicer, and argonaute-2 [ago-2]) and miRs (-7a and -150) and whether these changes impacted other parameters following ethanol and burn injury. Mice were gavaged with ethanol (∼2.9 g/kg) 4 h before receiving a ∼12.5% total body surface full thickness burn. Mice were resuscitated at the time of injury with normal saline with or without 5 mg/kg PX-478, a hypoxia-inducible factor-1α inhibitor. One day following injury mice were euthanized, and the expression of miRs and their biogenesis components as well as bacterial growth, tight junction proteins, intestinal transit, and permeability were assessed. Ethanol combined with burn injury significantly reduced expression of drosha, ago-2, miRs (-7a and -150), occludin, zonula occludens-1, claudin-4, zonula occludens-1, mucins-2 and -4, and intestinal transit compared to shams. Furthermore, there was an increase in intestinal permeability, total bacteria, and Enterobacteriaceae populations following the combined injury compared to shams. PX-478 treatment improved expression of drosha, ago-2, miRs (-7a and -150), occludin, claudin-4, zonula occludens-1, and mucin-2. PX-478 treatment also improved intestinal transit and reduced dysbiosis and permeability. These data suggest that PX-478 improves miR biogenesis and miR expression, and restores barrier integrity while reducing bacterial dysbiosis following ethanol and burn injury.