title: MicroRNA 181b-3p and its target importin α5 regulate toll-like receptor 4 signaling in Kupffer cells and liver injury in mice in response to ethanol.
abstract: Increased inflammatory signaling by Kupffer cells contributes to alcoholic liver disease (ALD). Here we investigated the impact of small, specific-sized hyaluronic acid of 35 kD (HA35) on ethanol-induced sensitization of Kupffer cells, as well as ethanol-induced liver injury in mice. Unbiased analysis of microRNA (miRNA) expression in Kupffer cells identified miRNAs regulated by both ethanol and HA35. Toll-like receptor 4 (TLR4)-mediated signaling was assessed in primary cultures of Kupffer cells from ethanol- and pair-fed rats after treatment with HA35. Female C57BL6/J mice were fed ethanol or pair-fed control diets and treated or not with HA35. TLR4 signaling was increased in Kupffer cells by ethanol; this sensitization was normalized by ex vivo treatment with HA35. Next generation sequencing of Kupffer cell miRNA identified miRNA 181b-3p (miR181b-3p) as sensitive to both ethanol and HA35. Importin α5, a protein involved in p65 translocation to the nucleus, was identified as a target of miR181b-3p; importin α5 protein was increased in Kupffer cells from ethanol-fed rats, but decreased by HA35 treatment. Overexpression of miR181b-3p decreased importin α5 expression and normalized lipopolysaccharide-stimulated tumor necrosis factor α expression in Kupffer cells from ethanol-fed rats. In a mouse model of ALD, ethanol feeding decreased miR181b-3p in liver and increased expression of importin α5 in nonparenchymal cells. Treatment with HA35 normalized these changes and also protected mice from ethanol-induced liver and intestinal injury.
  
  
  
  miR181b-3p is dynamically regulated in Kupffer cells and mouse liver in response to ethanol and treatment with HA35. miR181b-3p modulates expression of importin α5 and sensitivity of TLR4-mediated signaling. This study identifies a miR181b-3p-importin α5 axis in regulating inflammatory signaling pathways in hepatic macrophages. (Hepatology 2017;66:602-615).
authors.affiliation: Department of Pathobiology, Center for Liver Disease Research, Cleveland Clinic, Cleveland, Ohio.|Department of Molecular Medicine, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Paramananda
authors.initials: P
authors.lastname: Saikia
authors.affiliation: Department of Pathobiology, Center for Liver Disease Research, Cleveland Clinic, Cleveland, Ohio.|Department of Molecular Medicine, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Damien
authors.initials: D
authors.lastname: Bellos
authors.affiliation: Department of Pathobiology, Center for Liver Disease Research, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Megan R
authors.initials: MR
authors.lastname: McMullen
authors.affiliation: Department of Pathobiology, Center for Liver Disease Research, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Katherine A
authors.initials: KA
authors.lastname: Pollard
authors.affiliation: Department of Pathobiology, Center for Liver Disease Research, Cleveland Clinic, Cleveland, Ohio.|Department of Molecular Medicine, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Carol
authors.initials: C
authors.lastname: de la Motte
authors.affiliation: Department of Pathobiology, Center for Liver Disease Research, Cleveland Clinic, Cleveland, Ohio.|Department of Molecular Medicine, Case Western Reserve University, Cleveland, Ohio.|Department of Gastroenterology, Center for Liver Disease Research, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Laura E
authors.initials: LE
authors.lastname: Nagy
mesh_terms: D000818:Animals; D001707:Biopsy, Needle; D002478:Cells, Cultured; D004195:Disease Models, Animal; D000431:Ethanol / Q000009:adverse effects / Q000494:pharmacology*; D005260:Female; D005786:Gene Expression Regulation; D049671:History, 18th Century; D007150:Immunohistochemistry; D028884:Karyopherins / Q000187:drug effects / Q000235:genetics*; D007728:Kupffer Cells / Q000166:cytology / Q000378:metabolism; D008108:Liver Diseases, Alcoholic / Q000378:metabolism* / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D035683:MicroRNAs / Q000187:drug effects / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012016:Reference Values; D015398:Signal Transduction; D051197:Toll-Like Receptor 4 / Q000235:genetics*
chemical_list: D028884:Karyopherins; D035683:MicroRNAs; D051197:Toll-Like Receptor 4; D000431:Ethanol