Enrichment effect of vitamin-deficient diet of rats by polyunsaturated fatty acids ω-3 on vitamin biomarkers and antioxidant status
AbstractUsing the model of combined vitamin deficiency based on 5-fold reduction of the amount of vitamin mixture in semi-synthetic diet and on vitamin E exclusion from the mixture, the influence of ω-3 polyunsaturated fatty acids (PUFA) on vitamin and antioxidant status has been investigated. The enrichment of rat diet with PUFA was achieved by replacing of sunflower oil (4,5% of the diet) on linseed oil. This substitute led to ω-3 PUFA elevation from 0,03 to 2,4 g per 100 g of food and PUFA and saturated fatty acids diet ratio increased from 1,3 to 1,9. The diet treatment with PUFA did not affect blood plasma retinol concentration and total vitamin A (retinol palmitate and retinol) rat liver content, while liver retinol significantly 1,5-fold elevated. Despite of preliminary equation of tocopherols content in vegetable oils (up to 60 IU per 100 g by adding dl-alphatocopherol to linseed oil) the consuming of linen oil deteriorated animal vitamin E supply. The liver alpha-tocopherol content significantly decreased by 14%, its blood plasma concentration insignificantly decreased by 26%, while the amount of β- and γ-tocopherol significantly increased in 5,4-fold. At the same deprivation of vitamin D in the diet of rats treated with linseed oil 25(OH)D blood plasma concentration was 1,3-fold higher compared with the animals treated with sunflower oil, but the difference did not reach significance reliable. In this case, this index had significant differences from that of the receiving adequate diet rats in control group, having 2-fold higher concentration of vitamin D transport form in blood plasma. PUFA enrichment of the combined vitamin-deficit diet did not affect liver level of vitamin C, vitamin B1 and vitamin B2. Contrary to the assumptions, the enrichment with PUFA of vitamin-deficient diet did not lead to a further increase of liver MDA level and a decrease of liver ascorbic acid content, which is typical for animals in combined vitamin deficiency. The deterioration of vitamin E status at enriched with PUFA vitamin-deficient diet requires the additional intake of this vitamin for maintaining of vitamin E sufficiency.
Keywords:vitamins, combined vitamin deficiency, omega-3 polyunsaturated fatty acids, linseed oil, antioxidant status, liver, blood plasma, urinary excretion, rats