title: Downregulation of cellular protective factors of rumen epithelium in goats fed high energy diet.
abstract: Energy-rich diets can challenge metabolic and protective functions of the rumen epithelial cells, but the underlying factors are unclear. This study sought to evaluate proteomic changes of the rumen epithelium in goats fed a low, medium, or high energy diet. Expression of protein changes were compared by two-dimensional differential gel electrophoresis followed by protein identification with matrix assisted laser desorption ionisation tandem time-of-flight mass spectrometry. Of about 2,000 spots commonly detected in all gels, 64 spots were significantly regulated, which were traced back to 24 unique proteins. Interestingly, the expression profiles of several chaperone proteins with important cellular protective functions such as heat shock cognate 71 kDa protein, peroxiredoxin-6, serpin H1, protein disulfide-isomerase, and selenium-binding protein were collectively downregulated in response to high dietary energy supply. Similar regulation patterns were obtained for some other proteins involved in transport or metabolic functions. In contrast, metabolic enzymes like retinal dehydrogenase 1 and ATP synthase subunit beta, mitochondrial precursor were upregulated in response to high energy diet. Lower expressions of chaperone proteins in the rumen epithelial cells in response to high energy supply may suggest that these cells were less protected against the potentially harmful rumen toxic compounds, which might have consequences for rumen and systemic health. Our findings also suggest that energy-rich diets and the resulting acidotic insult may render rumen epithelial cells more vulnerable to cellular damage by attenuating their cell defense system, hence facilitating the impairment of rumen barrier function, typically observed in energy-rich fed ruminants.
authors.affiliation: Department for Farm Animals and Veterinary Public Health, Institute of Animal Nutrition and Functional Plant Compounds, Vetmeduni Vienna, Vienna, Austria.
authors.forename: Manfred
authors.initials: M
authors.lastname: Hollmann
authors.affiliation: Department of Biomedical Sciences, Institute of Medical Biochemistry, Vetmeduni Vienna, Vienna, Austria.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Miller
authors.affiliation: VetCore Facility for Research, Vetmeduni Vienna, Vienna, Austria.
authors.forename: Karin
authors.initials: K
authors.lastname: Hummel
authors.affiliation: VetCore Facility for Research, Vetmeduni Vienna, Vienna, Austria.
authors.forename: Sonja
authors.initials: S
authors.lastname: Sabitzer
authors.affiliation: Department for Farm Animals and Veterinary Public Health, Clinic for Swine, Vetmeduni Vienna, Vienna, Austria.
authors.forename: Barbara U
authors.initials: BU
authors.lastname: Metzler-Zebeli
authors.affiliation: VetCore Facility for Research, Vetmeduni Vienna, Vienna, Austria.
authors.forename: Ebrahim
authors.initials: E
authors.lastname: Razzazi-Fazeli
authors.affiliation: Department for Farm Animals and Veterinary Public Health, Institute of Animal Nutrition and Functional Plant Compounds, Vetmeduni Vienna, Vienna, Austria.
authors.forename: Qendrim
authors.initials: Q
authors.lastname: Zebeli
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000818:Animals; D004032:Diet; D015180:Electrophoresis, Gel, Two-Dimensional; D002149:Energy Intake / Q000235:genetics* / Q000276:immunology; D004848:Epithelium / Q000276:immunology / Q000378:metabolism*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006041:Goats / Q000276:immunology / Q000378:metabolism*; D018832:Molecular Chaperones / Q000235:genetics / Q000276:immunology; D020543:Proteome / Q000235:genetics* / Q000276:immunology; D012417:Rumen / Q000276:immunology / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D018832:Molecular Chaperones; D020543:Proteome