[Correlation of serum pro-inflammatory [IL 6] and anti-inflammatory [IL 10] interleukine levels with fatty acid composition of dietary oils in rats]

ABSTRACT

Nowadays, proposing dietary recommendations to regulate serum inflammatory mediators is of immense importance. This study is designed to evaluate the effects of different commercial dietary oils which have more complicated effects than pure fatty acids on serum levels of interleukins IL 6 and IL 10. In this experimental animal study, 40 male rats were divided into 5 groups and received standard chow diet for 3 weeks. At the end of the 3[rd] week, four rats from each of the 5 groups were sacrificed and blood samples were collected. The remaining rats then received chow diet or an experimental diet containing yogurt butter, olive oil, soybean oil, or flaxseed oil for another 4 weeks. Then, blood samples were collected and serum fatty acid composition was determined by gas chromatography and serum levels of interleukins were obtained by use of ELISA kits. We used variance analysis for comparison of the mean values and regression analysis for assessment of correlation among variables. Consumption of yogurt butter and soybean oil significantly increased serum level of IL 6, whereas IL 10 level increased after consumption of flaxseed oil [p<0.05]. Increase in serum n-6 PUFA, led to a notable increase in IL 6 concentration, but increase in serum MUFA gave rise to decreased IL 6 level. A direct relationship was observed between the levels of arachidonic acid and IL 6. In addition, the level of IL 6 decreased when serum decosahexaenoic acid increased. We showed that composition of serum fatty acids can modulate concentrations of the interleukins. Using oils containing n-6 PUFA led to generation of pro inflammatory mediators, but oils containing n-3 polyunsaturated fatty acids showed anti inflammatory effects.