Protective Effect Of Pilose Antler Protein On LPS Induced Intestinal Inflammation In Mice

The nutrients required for human normal activities are provided by the gut,so the intestinal system plays an important role in nutrient absorption and mucosal immunity.Lipopolysaccharide(LPS)is the main component of cell wall of Gram-negative bacteria,and it is also a stimulant of the intestinal immune system,which can be used to induce acute intestinal inflammation in mice.The purpose of this study was to investigate the effects of water extract protein from sika deer,red deer and hybrid of the two on the growth index,blood biochemical index,oxidative stress level,inflammatory gene expression and intestinal morphology of LPS induced intestinal inflammation mice,and provide theoretical basis for the prevention and application of antler water extract peptide as intestinal nutrient in the prevention and application of intestinal inflammation.The following five aspects of the experiment were conducted in this study:Experiment 1: the extraction of antler protein and the effect of antler protein on the weight gain of miceThe single factor analysis was used to analyze the effect of different ultrasonic solvents on the protein concentration in the extracted protein solution.The results show that under ultrasonic condition,water is the ultrasonic solvent to extract protein,and the concentration of protein solution is the highest.One hundred and twenty Kunming mice with weight of 21g-22 g were were used and randomly divided into 12 groups(n = 10).Three groups were set up as control groups,namely normal saline blank,lipopolysaccharide negative and vitamin C positive groups.Animals in control groupswere given the normal saline for 14 days,and animals in 9 experimental groups were given low,medium and high doses(50,100 and 200mg/kg)of antler protein from 3 kinds of deeri for 14 days.At the end of test,the end weight of the mice in the experimental group was higher than that of the blank group and the negative control group.The high dose group of sika deer antler protein had the greatest influence on the weight of mice,the best effect and the difference was significant(P < 0.01).In conclusion,antler protein can improve the growth performance of mice,and the weight gain of mice is dose-dependent with antler polypeptide in the scope of experimental design.Experiment 2: the effect of antler protein on the immune and inflammatory factors of LPS induced intestinal inflammatory in miceBlood immune index and inflammatory factors were determined using ELISA kit.The results showed that the levels of IL-6,IL-1 β and ifn-γ in the negative group were significantly higher than those in the control group(P < 0.01),the levels of Ig A and Ig G were significantly reduced.Antler protein could effectively inhibit the increase of IL-6,IL-1 β and ifn-γ levels in the blood of mice caused by LPS,and the difference was very different from the negative group.The concentration of Ig A and Ig G in the blood of mice was significantly increased(P < 0.01).The inhibition effect of three inflammatory factors in serum of mice was better in the high dose group of antler protein and hybrid antler protein group,and the ability of increasing Ig A and Ig G in the serum of mice in the high dose group was better than that of other groups.Experiment 3: the effect of antler protein on oxidative stress induced by LPS in mice with intestinal inflammationThe oxidative stress level in mice was determined by measuring the content and activity of NO,SOD and CAT in the liver of mice.The results showed that LPS significantly increased the level of NO in the negative group(P < 0.01),the SOD activity was significantly decreased,the CAT activity was not significantly affected.Compared with the negative group,antler protein could significantly reduce the NO caused by LPS,(P < 0.01),the activity of SOD in mice was significantly increased(P< 0.01),which was in dose dependent.To conclude,the antioxidant activity of the high dose group of antler protein in mice was better than that of other groups.Experiment 4: the effect of antler protein on the expression of inflammatory gene in LPS induced intestinal inflammatory miceThe total RNA was extracted from liver and intestinal tissues by Trizol extract.The RNA quality and concentration were detected.The expression of inflammatory factors in liver and jejunum tissues was detected by fluorescence quantitative PCR.18 S was used as internal gene to detect the relative expression of IL-1 β,nlrp1 and NLRP3 inflammatory corpuscles in mice liver and jejunum.The results showed that the expression of three inflammatory factors in the liver and jejunum of the negative group was significantly higher than that in the blank group(P < 0.01),Compared with the negative group,the relative expression of IL-1 β,nlrp1 and NLRP3 were significantly reduced by antler protein treatments(P < 0.01).In conclusion,the overall inhibition effect of three inflammatory factors in the high dose group of antler protein was better than that of other groups.Experiment 5: the effect of antler protein on intestinal morphology of LPS induced intestinal inflammation miceThe villi length and depth of the intestinal tissue were observed by microscope after dewater and transparency treatments of duodenum,jejunum and ileum samples of mice,and the results showed that villi length and the villi / crypt ratio of the mice in antler protein test group,positive group and blank group were significantly higher than those in the negative group.Antler protein had obvious effect on duodenal villi,crypt and villus / crypt of LPS induced enteritis mice.The effect of the high dose group on the comprehensive improvement of duodenal intestinal morphology and the effect of jejunal intestinal morphology was better than that of other groups.The overall improvement effect of hybrid antler protein group on the intestinal morphology of mice was better than other antler polypeptide components.