title: Fatty acid-mediated endoplasmic reticulum stress in vivo: differential response to the infusion of Soybean and Lard Oil in rats.
abstract: BACKGROUND
  In cell systems, saturated fatty acids, compared to unsaturated fatty acids, induce a greater degree of ER stress and inflammatory signaling in a number of cell types, including hepatocytes and adipocytes. The aim of the present study was to determine the effects of infusions of lard oil (enriched in saturated fatty acids) and soybean oil (enriched in unsaturated fatty acids) on liver and adipose tissue ER stress and inflammatory signaling in vivo.
  
  
  METHODS
  Lipid emulsions containing glycerol, phosphatidylcholine, antibiotics (Control, n=7) and either soybean oil (Soybean, n=7) or lard oil (Lard, n=7) were infused intravenously into rats over a 4 h period.
  
  
  RESULTS
  Plasma free fatty acid levels were 0.5±0.1 mmol/L (mean±SD) in Control and were increased to 1.0±0.3 mmol/L and 1.1±0.3 mmol/L in Soybean and Lard, respectively. Glucose and insulin levels were not different among groups. Markers of endoplasmic reticulum (ER) stress and activation of inflammatory pathway signaling were increased in liver and adipose tissue from Soybean and Lard compared to Control, but were increased to a greater extent in Lard compared to Soybean.
  
  
  CONCLUSIONS
  These data suggest that elevated plasma free fatty acids can induce hepatic and adipose tissue ER stress and inflammation in vivo. In addition, saturated fatty acids appear to be more cytotoxic than unsaturated fatty acids in vivo.
authors: Department of Food Science and Human Nutrition, Colorado State University, Fort Collins, CO 80523-1571, USA.
authors: Angela M
authors: AM
authors: Nivala
authors: Lauren
authors: L
authors: Reese
authors: Melinda
authors: M
authors: Frye
authors: Christopher L
authors: CL
authors: Gentile
authors: Michael J
authors: MJ
authors: Pagliassotti
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism; D004041:Dietary Fats / Q000008:administration & dosage*; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage*; D059865:Endoplasmic Reticulum Stress / Q000187:drug effects*; D005227:Fatty Acids / Q000009:adverse effects*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D018836:Inflammation Mediators / Q000097:blood / Q000378:metabolism; D007262:Infusions, Intravenous; D007328:Insulin / Q000097:blood; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013024:Soybean Oil / Q000008:administration & dosage*
chemical_list: D001786:Blood Glucose; D004041:Dietary Fats; D004042:Dietary Fats, Unsaturated; D005227:Fatty Acids; D005230:Fatty Acids, Nonesterified; D018836:Inflammation Mediators; D007328:Insulin; D013024:Soybean Oil; C029310:lard