Effect Of Lycopene On Intestinal Barrier Function In Animals Under Restraint Stress And Growth Performance Of Finishing Pigs

In modern pig farming,stress from excessive rearing density and limited feeding space induced by intensive breeding,which decreased growth performance,sperm motility of boars,and increased the abortion of sows.Previous research in our laboratory found that lycopene alleviated intestinal flora disturbances induced by stress in female mice,but the role of lycopene in fattening pigs remains unclear.This study was established to study the effect of lycopene on intestinal barrier and antioxidant function in male mice and verified its effect on growth performance in finishing pigs.The results will provide a solution to alleviate the stress,and further provides a theoretical basis for the application of plant extract lycopene in livestock.Eight-week-old Kunming male mice were randomly divided into 4 groups:(1)Control group(CON);(2)Restraint Stress(RS);(3)LYC + Restraint stress(LRS)group;(4)Corn oil + Restraint stress(CRS).The lycopene administered by gavage at a dose of 10 mg/kg/body weight/day for 14 days.Two hours of lycopene or corn oil pre-treatment was applied to the animals in CRS and LRS groups before restraint stress treatment(5 hours/day).Take duodenum,jejunum and ileum tissue.The main findings are as follows:1.Compared with RS group,the weight loss of male mice and the change of blood glucose in the LRS group pretreated with lycopene was significantly reduced(P<0.05).The average daily feed intake of male mice in LRS group was increased.These results indicated that lycopene could increase the body weight and decrease the blood glucose but had no significant effect on the daily feed intake.2.Compared with the RS group,the positive expression rate of PCNA in duodenum,jejunum and ileum was significantly increased(P<0.05).The intestinal morphological structure of duodenum,jejunum and ileum in the LRS group was improved,and the villus-crypt ratio was significantly increased(P<0.05).The transcription levels of pro-inflammatory factors TNF-α,IL-2 and IFN-γ m RNA in duodenum,jejunum and ileum were significantly decreased(P<0.05),and the transcription level of anti-inflammatory factor IL-4 m RNA was significantly increased(P<0.05).The results of 16 S r RNA Illumina high-throughput sequencing showed that lycopene pretreatment increased the richness and diversity of cecal microflora.The relative abundance of Tenericutes was significantly increased at the phylum level(P<0.05),and the abundance of Alloprevotella was significantly increased at the genus level(P<0.05).The above results indicated that lycopene could improve the intestinal morphology and intestinal flora structure,increase the expression of PCNA,regulate the transcription level of intestinal inflammatory factors,and alleviate the adverse effects of restraint stress on the intestine.Therefore,lycopene could increase intestinal crypt cell proliferation,improve intestinal physical barrier and intestinal flora structure,and regulate intestinal local immune level.3.Compared with RS group,the contents of SOD,GSH-PX and T-AOC of duodenum,jejunum and ileum tissues in LRS group was significantly increased(P<0.05),the content of MDA was significantly decreased(P<0.05).The expression of Nrf2 and HO-1 in duodenum,jejunum and ileum tissues(P<0.05)and the expression of p-AKT/AKT in ileum tissues were significantly increased(P<0.05).Therefore,lycopene could activate the AKT-Nrf2 / HO-1 signaling pathway to limit the level of intestinal oxidative stress in intestine of male mice under restraint stress.4.The average daily gain and average daily feed intake of finishing pigs in the groups supplemented with 100,200 and 400 mg/kg lycopene(purity 20 %)tended to increase,and the ratio of feed to gain decreased,but not significantly different from the CON group which fed the basal diet(P>0.05).The results showed that the addition of lycopene in feed was beneficial to improve the growth performance of finishing pigs.In conclusion,lycopene may be effective in mitigating restraint stress-induced stress hyperglycemia.In addition,lycopene exhibits the protective effect on intestinal damage by promoting intestinal crypt cell proliferation,improving intestinal mucosal damage,and activating the AKT/Nrf2-HO-1 signaling pathway regulates local oxidative stress in the small intestine.Besides,diet supplementation with 400 mg/kg lycopene(purity 20%)improved the growth performance of finishing pigs.