title: The effect of short-term canola oil ingestion on oxidative stress in the vasculature of stroke-prone spontaneously hypertensive rats.
abstract: BACKGROUND
  This study aimed to determine if 25 days of canola oil intake in the absence of excess dietary salt or together with salt loading affects antioxidant and oxidative stress markers in the circulation. A further aim was to determine the mRNA expression of NADPH oxidase subunits and superoxide dismutase (SOD) isoforms in the aorta of stroke-prone spontaneously hypertensive (SHRSP) rats.
  
  
  METHODS
  Male SHRSP rats, were fed a defatted control diet containing 10% wt/wt soybean oil or a defatted treatment diet containing 10% wt/wt canola oil, and given tap water or water containing 1% NaCl. Blood was collected at the end of study for analysis of red blood cell (RBC) antioxidant enzymes, RBC and plasma malondialdehyde (MDA), plasma 8-isoprostane and plasma lipids. The aorta was removed and the mRNA expression of NOX2, p22phox, CuZn-SOD, Mn-SOD and EC-SOD were determined.
  
  
  RESULTS
  In the absence of salt, canola oil reduced RBC SOD and glutathione peroxidase, and increased total cholesterol and LDL cholesterol compared with soybean oil. RBC glutathione peroxidase activity was significantly lower in both the salt loaded groups compared to the soybean oil only group. In addition, RBC MDA and plasma HDL cholesterol were significantly higher in both the salt loaded groups compared to the no salt groups. Plasma MDA concentration was higher and LDL cholesterol concentration lower in the canola oil group loaded with salt compared to the canola oil group without salt. The mRNA expression of NADPH oxidase subunits and SOD isoforms were significantly reduced in the canola oil group with salt compared to canola oil group without salt.
  
  
  CONCLUSIONS
  In conclusion, these results indicate that canola oil reduces antioxidant status and increases plasma lipids, which are risk factors for cardiovascular disease. However, canola oil in combination with salt intake increased MDA, a marker of lipid peroxidation and decreased NAPDH oxidase subunits and aortic SOD gene expression.
authors: School of Medicine, Deakin University, Victoria, Australia.
authors: Annateresa
authors: A
authors: Papazzo
authors: Xavier
authors: X
authors: Conlan
authors: Louise
authors: L
authors: Lexis
authors: Paul
authors: P
authors: Lewandowski
mesh_terms: D000818:Animals; D001011:Aorta / Q000201:enzymology / Q000378:metabolism*; D015415:Biomarkers / Q000097:blood; D004039:Diet, Sodium-Restricted; D015237:Dinoprost / Q000031:analogs & derivatives / Q000097:blood; D004912:Erythrocytes / Q000201:enzymology / Q000378:metabolism; D005229:Fatty Acids, Monounsaturated / Q000009:adverse effects* / Q000627:therapeutic use; D015971:Gene Expression Regulation, Enzymologic; D006937:Hypercholesterolemia / Q000209:etiology / Q000517:prevention & control; D006973:Hypertension / Q000097:blood / Q000178:diet therapy* / Q000503:physiopathology*; D007527:Isoenzymes / Q000097:blood / Q000235:genetics / Q000378:metabolism; D015227:Lipid Peroxidation; D008297:Male; D018384:Oxidative Stress; D010088:Oxidoreductases / Q000097:blood / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011897:Random Allocation; D000074262:Rapeseed Oil; D051381:Rats; D011918:Rats, Inbred SHR; D012307:Risk Factors; D020521:Stroke / Q000209:etiology* / Q000517:prevention & control
chemical_list: D015415:Biomarkers; D005229:Fatty Acids, Monounsaturated; D007527:Isoenzymes; D012333:RNA, Messenger; D000074262:Rapeseed Oil; C075750:8-epi-prostaglandin F2alpha; D015237:Dinoprost; D010088:Oxidoreductases