title: Evidence of endoplasmic reticulum stress and liver inflammation in the American mink Neovison vison with benign hepatic steatosis.
abstract: We investigated the presence of inflammatory signs in the progression of fatty liver disease induced by fasting. Sixty standard black American mink (Neovison vison) were fasted for 0, 1, 3, 5, or 7 days and one group for 7 days followed by re-feeding for 28 days. Liver sections were evaluated histologically and liver mRNA levels indicating endoplasmic reticulum (ER) stress, adipogenic transformation, and inflammation were assessed by quantitative real-time PCR. After 3 days of fasting, the mink had developed moderate liver steatosis. Increased hyaluronan reactivity in lymphocytic foci but no Mallory-Denk bodies were seen in livers of the mink fasted for 5-7 days. Up-regulation of glucose-regulated protein, 78 kDa was observed on day 7 indicating ER stress, especially in the females. Liver lipoprotein lipase and monocyte chemoattractant protein 1 mRNA levels increased in response to 5-7 days of food deprivation, while tumor necrosis factor α (TNF-α) was the highest in the mink fasted for 5 days. The expression of the genes of interest, except for TNF-α, correlated with each other and with the liver fat content. The mRNA levels were found to change more rapidly below n-3/n-6 polyunsaturated fatty acid ratio threshold of 0.15. Following re-feeding, hepatocyte morphology and mRNA abundance returned to pre-fasting levels. Within the studied timeframe, evidence for ER stress, adipogenic transformation, and liver inflammation suggested incipient transition from steatosis to steatohepatitis with potential for development of more severe liver disease. This may present a possibility to influence disease progression before histologically observable steatohepatitis.
authors: Department of Plant and Animal Sciences, Faculty of Agriculture, Dalhousie University, P.O. Box 550, Truro, NS, B2N 5E3, Canada, kirsti.rouvinen-watt@dal.ca.
authors: Kirsti
authors: K
authors: Rouvinen-Watt
authors: Catherine
authors: C
authors: Pal
authors: Timothy
authors: T
authors: Martin
authors: Lora
authors: L
authors: Harris
authors: Tessema
authors: T
authors: Astatkie
authors: Darya
authors: D
authors: Kryzskaya
authors: Vesa
authors: V
authors: Kärjä
authors: Anne-Mari
authors: AM
authors: Mustonen
authors: Raija
authors: R
authors: Tammi
authors: Markku
authors: M
authors: Tammi
authors: Petteri
authors: P
authors: Nieminen
mesh_terms: D000818:Animals; D018932:Chemokine CCL2 / Q000235:genetics; D004195:Disease Models, Animal; D000091342:Endoplasmic Reticulum Chaperone BiP; D059865:Endoplasmic Reticulum Stress; D005234:Fatty Liver / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D005260:Female; D005508:Food Deprivation; D006360:Heat-Shock Proteins / Q000235:genetics; D008071:Lipoprotein Lipase / Q000235:genetics; D008099:Liver / Q000378:metabolism / Q000473:pathology; D008297:Male; D008907:Mink; D012333:RNA, Messenger / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics
chemical_list: D018932:Chemokine CCL2; D000091342:Endoplasmic Reticulum Chaperone BiP; D006360:Heat-Shock Proteins; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D008071:Lipoprotein Lipase