Effects Of Composite Antioxidants On Oxidative Stress And Intestinal Tract In Animals

Objective:In this experiment we studied the changes between free radicals metaboli and the morphological structure, physiological function of intestinal tract under oxidative stress and discussed the effects of composite antioxidant. To investigate the relationship among free radicals metaboli, composite antioxidant and intestinal tract, we also studied the effects of composite antioxidants on reparation.Methods: Experiment 1: 36 healthy SD rats as 42 days of age were randomly divided into three groups with twelve rats in each group. The control group and induction group was fed basal diet and the repair group was fed with composite antioxidant including vitamin C, vitamin E, tea polyphenols and microbial antioxidants. The feeding trial lasted for 22 days. On the 5th,9th,13th,17th day, rats in induction and repair group received an injection of 0.8 mg LPS/kg while rats in control group received of same amount of saline. On the 22nd day of experiment, 6 rats in each group were randomly selected, received D-xylose supplementation. The content of serum MDA, activities of liver SOD, GSH-Px, lipase, maltase and the length, width of intestinal villi were determined.Experiment 2: 12 litters of 14-day-old piglets were randomly divided into three groups with 4 litters each. The control group and weaning group were fed basal diet and the repair group was fed composite antioxidant including vitamin C, vitamin E, tea polyphenols, Alpha Lipoic Acid and microbial antioxidants. The feeding trial lasted for 22 days, the induction and repair group were weaned on 21-day-old. On the 21, 28, 35- day-old, the piglets were took blood and on the 24-day-old, 1 piglets in each group were randomly selected, received D-xylose supplementation. The content of serum/liver MDA, NO, activities of serum/liver SOD, GSH-Px, CAT, digestive enzymes and the structure of intestinal villi were determined.Results: Experiment 1: The ADG of rats in induction group was lower (P<0.05) than that in control group and the concentration of MDA was higher (P<0.05) and the activity of GSH-Px was lower (P<0.05). The liver coefficient, D-(+)-Xylose concentration in rats'serum, the activities of lipase and maltase in induction were 11.13%, 72.72%, 66% and 65.74% lower (P<0.05) respectively than that in control group. The villus height was lower (P<0.05) and the crypt depth was deeper (P<0.05) than that in control group. While the concentration of MDA was 49.31% lower, the activities of SOD and GSH-Px were 40.96% and 35.04% higher than that in induction group; the liver coefficient, D-(+)-Xylose concentration in rats'serum, the activity of maltase and the villus height were higher; the crypt depth were shallower than that in induction group.Experiment 2: Compared with the control group, 28, 35-day-old piglets in weaning group noticeable decrease the weight by 18.45% and 28.39%, the concentration of O₂ by 6.32% and 11.81%, the activities of serum SOD by 47.81%(P<0.05). And also the activities of trypsase, lipase, amylase, maltase, invertase and DAO were lower (P<0.05). Weaning group piglets on 21, 35-day-old increased the concentration of NO by 199.42% and 34.00%, the contents of serum MDA on 35-day-old by 78.14%, the pH value of ileum by7.11 and the content of serum NO was also higher (P<0.05). Compared with the weaning group, the repair group remarkable decreased the concentration of NO by 30.86% and 22.81%, the contents of NO on 28, 35-day-old by 50.07% and 52.46%, MDA by 33.45% (P<0.05) and 38.15%, the pH value of ileum by 5.36%. The repair group piglets dramaticly increased the concentration of O₂ on 28, 35-day-old by 7.76%, the activity of SOD by 61.48% and 6.15%, and the activities of maltase, trysase in intestine and pancreas were 30.54%, 70.11% and 100.35% higher (P<0.05). The related coefficient and linear regression among the concentration of H2O₂, NO, the length of intestine villus and the activities of trypsinase were notable (P<0.05).Conclusion: The oxidative stress induced by LPS or weaning can cause animal to produce a large number of free radicals, the ability of antioxidation was decreased and had damage to the structure and function of intestinal tract. The key points of oxidative stress and repairation in animal body were H2O₂, NO, intestine villus and trypsinase. Adding composite antioxidants to the stress and weaning piglets can significantly increase the ability of antioxidantion, reduces peroxidation and also have an effect on intestine reparation, enhancing the function of digestion. Adding composite antioxidants has a good effect on oxidative stress.