The objective of the present study was to evaluate a potential of Schizochytrium microalga oil to alleviate possible negative effects of high-fat-high-energy diets. Forty adult male rats (Wistar Albino) were fed 7 weeks the diet containing beef tallow + evaporated sweetened milk (diet T) intended to cause mild obesity and low-grade systemic inflammation. Consequently, the animals were divided into four groups by 10 animals each and fed either the T-diet (control) or the diet containing 6% of safflower oil (S), 6% of fish oil (F) and 6% of Schizochytrium microalga oil (A), respectively, for another 7 weeks. The A-diet decreased (p < 0.05) live weight to 86% and glycaemia to 85% of control, respectively; an effect of the S- and F-diet on these markers was insignificant (p > 0.05). In comparison with control, higher (p < 0.05) deposition of eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) in the epididymal adipose tissue (EAT) of the A-rats correlated with increased (p < 0.05) plasma adiponectin concentration, but it was without the effect (p > 0.05) on cellular adiponectin content in the EAT. Higher (p < 0.05) EPA+DHA deposition in the liver of the A-rats correlated with higher expression (149% of control; p < 0.05) of the gene coding for peroxisome proliferator-activated receptor gamma, and with lower expression (82% and 66%; p < 0.05) of the genes coding for adiponectin receptors AdipoR1 and AdipoR2; no relationship to the expression of receptor GPR120 was found. The A-diet did not affect amount of the nuclear fraction of the nuclear factor kappa B in the liver, but increased plasma level of anti-inflammatory cytokine TGF-β1 (p < 0.05). The presented data agree with results of other in vivo rodent and human studies, but not with literature data regarding in vitro experiments: it can be concluded that the effects of dietary oils on inflammatory markers need further investigation.
- MeSH
- adiponektin genetika metabolismus MeSH
- cytokiny genetika metabolismus MeSH
- dieta veterinární MeSH
- krmivo pro zvířata analýza MeSH
- krysa rodu rattus MeSH
- mikrořasy chemie MeSH
- náhodné rozdělení MeSH
- NF-kappa B genetika metabolismus MeSH
- oleje rostlin chemie farmakologie MeSH
- potkani Wistar MeSH
- PPAR gama genetika metabolismus MeSH
- regulace genové exprese účinky léků MeSH
- zánět farmakoterapie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The purpose of the study was to test the hypothesis that the dietary oils with different content of n-3 polyunsaturated fatty acids (PUFA) eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) affect plasma lipid level in rats in a different degree. The diets with 6% of fish oil (FO) and Schizochytrium microalga oil (SchO; EPA+DHA content in the diets 9.5 + 12.3 and 2.6 + 29.5% of the sum of total fatty acids, respectively) were used; the diet with 6% of safflower oil (high content of n-6 PUFA linoleic acid, 65.5%; EPA+DHA content 0.7 + 0.9%) was used as a control. The difference between FO and SchO was established only in the case of plasma triacylglycerol (TAG) level: plasma TAG of the FO-fed rats did not differ from the control rats (p > 0.05), while SchO decreased (p < 0.05) plasma TAG to 46% of the control. On the other hand, FO and SchO decreased (p < 0.05) total plasma cholesterol (TC) in rats in the same extent, to 73% of the control. Regarding the underlying mechanisms for the TC decrease, both SchO and FO up-regulated hepatic Insig-1 gene (181 and 133% of the control; p < 0.05), which tended (p = 0.15 and p = 0.19 respectively) to decrease the amount of hepatic nSREBP-2 protein (61 and 66% of the control). However, neither SchO nor FO influenced hepatic 3-hydroxy-3-methyl-glutaryl-CoA reductase gene expression (p > 0.05); SchO (but not FO) increased (p < 0.05) low-density lipoprotein receptor mRNA in the liver. It was concluded that the decrease of total plasma cholesterol might be caused by an increased cholesterol uptake from plasma into the cells (in the case of SchO), but also by other (in the present study not tested) mechanisms.
- MeSH
- cholesterol krev MeSH
- dieta MeSH
- játra chemie metabolismus MeSH
- krmivo pro zvířata analýza MeSH
- krysa rodu rattus MeSH
- mikrořasy chemie MeSH
- náhodné rozdělení MeSH
- nenasycené mastné kyseliny chemie metabolismus MeSH
- oleje rostlin chemie farmakologie MeSH
- potkani Wistar MeSH
- protein SREBP2 genetika metabolismus MeSH
- regulace genové exprese účinky léků MeSH
- rybí oleje chemie farmakologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH