A Comparative Study On The Antioxidant Activity Of Different Antioxidants And Their Effects On Food Intake In Mice

The various nutrients such as vitamins, lipid and protein, etc. in the diet are easy to be oxidized and to go rancid during the transportation and storage under the condition of high temperature environment, which resulted in a decrease of palatability and nutritional value of feed. Adding an appropriate amount of antioxidant in the diet can effectively prevent the occurrence of the above phenomenon. Meanwhile, the antioxidants can also elicit the effects of anti-inflammation, anti-disease through scavenging the excess free radicals, relieving oxidative stress and improving the oxidation resistance in animals.Recent studies have demonstrated that antioxidants can also promote food intake in animals via decreasing the hypothalamic ROS levels and increasing hypothalamic neuropeptides Ag RP / NPY.The aim of the present study was to screen the antioxidants that were able to regulate the animal food intake and to explore the underlying mechanism. Firstly, in vitro antioxidant test(comparison of the antioxidant ability to remove DPPH free radical and hydroxyl free radicals) we used to found out several antioxidants have a strong ability to scavenge free radicals. Meanwhile, we investigated the effects of the selected antioxidants with strong antioxidant activity on food intake in Kunming mice. In addition, the influence of the select antioxidants on oxidation resistance abilities of mice and the mechanisms involved in regulating feed intake in mice were explored. These results may provide the experimental basis for application of antioxidants in the animal production.The results showed as follows:(1) The ability of scavenging DPPH free radical and hydroxyl free radical of Rosemary acid is stronger than that of VC, while procyanidins, caffeic acid and syringic acid have the same ability as that of VC.(2) Diets supplemented with caffeic acid and syringic acid could significantly increase the average daily feed intake of mice, while diet containing 0.5% procyanidins couldsignificantly improve the average daily gain of mice. However, Rosemary acid had no significant effect on average daily feed intake and daily gain of mice.(3) Diets supplemented with 0.5% procyanidins or 0.3% caffeic acid could significantly increase the average daily feed intake of mice, with no significant effect on average daily feed intake and daily gain of mice. Diet containing 0.5% procyanidins plus0.3% caffeic acid could significantly increase both average daily feed intake and average daily gain of mice, and significantly reduce the hypothalamus ROS levels, promote the hypothalamic neuropeptides Ag RP/ NPY protein expression of mice.(4) Diets containing 0.5% procyanidins or 0.3% caffeic acid or 0.5%procyanidins+0.3% caffeic acid had no significant effect of antioxidant system in mice.In conclusion, these resulted demonstrated that procyanidins and caffeic acid has strong antioxidant capacity. Diets containing 0.5% procyanidins and 0.3% of caffeic acid significantly promote the feed intake of mice by decreasing ROS levels in the hypothalamus and increasing protein expression of Ag RP/ NPY in mice, with no effect on oxidative resistance of mice.