| Intestine is the largest and most complex digestive organ in animals,which plays an important physiological function of the body.In the process of breeding,many factors lead to animal enteritis,which leads to the stagnation of animal growth and reproduction,and the reduction of feed conversion rate.The serious enteritis brings death,and many farms suffer losses.Enteritis not only leads to a great decline in economic benefits,but also causes many product problems followed by the abuse of antibiotics.The antibiotics abuse greatly endangers the public health and safety of human and livestock.It is urgent to find scientific methods to prevent and treat enteritis.Effective probiotics replace antibiotics to become green and pollution-free additives,which not only effectively controls the overuse of antibiotics,but also reduces the production cost of livestock and poultry breeding industry in China.However,there are not many kinds of probiotic products in the market at present,and fewer choices of specific prevention and treatment of enteritis.Therefore,it is more and more important to screen more excellent probiotics instead of antibiotics to prevent and treat animal enteritis.It is suggested that symbiotic microbiota,gut immune system,epigenetic modification are closely related to the occurrence and development of enteritis.In epigenetic modification,DNA modification has been reported to cause intestinal diseases.According to the genetic law of biological information,there must be RNA modification.Among them,m6A(N6 methyladenosine)RNA modification is the most extensive modification in RNA modification,but the research on this aspect is still very little.This experiment tried to screen for probiotics with excellent performance,to explore the role of probiotics in the regulation of m6A methylation to improve animal enteritis,so as to provide a healthy choice of prevention and treatment for animal husbandry in solving the problem of intestinal inflammation,and provide theoretical basis of it.This study is divided into the following three parts:1 The relationship between the methylation level of RNA m6A and intestinal inflammationThe occurrence of enteritis in animal husbandry is related to many factors.The typical factors such as bacteria,virus and improper feeding management are easy to cause intestinal inflammation,but the mechanism is still not clear.In this study,we investigated the effect of RNA m6A methylation on enteritis.TNF-α(Tumor necrosis factor α)was used to establish inflammatory injury model of intestinal organoids in vitro,and indomethacin was used to establish animal enteritis model in vivo.The results both showed that with the production of inflammation,the level of inflammation was increased,Wnt/β-catenin signal pathway was down regulated,and the proliferation of intestinal stem cells was destroyed.The expression level of METTL14(methyltransferase-like 14),FTO(fat-mass and obesity-associated protein)and other RNA m6A methylation related enzymes increased significantly,the overall methylation level detected directly also increased by colorimetry.The pathological changes of intestine were obvious.It was preliminarily speculated that there was a great relationship between the occurrence of inflammation and the change of RNA m6A methylation level.2 Study on the mechanism of intestinal methylation aggravating inflammationIn order to explore the role of genetic epigenetic modification in the regulation of enteritis,the intestinal organoids model was used for study.In the previous experiments,it was found that demethylase FTO changed significantly in the progress.Then,the changes of methylation level and inflammation development were observed by inhibiting the expression of FTO.The crypt was divided into control group,inflammatory group,inhibitor group and inflammatory group treated with inhibitor.This research found that the inhibitor had no effect on cell activity and the expression of FTO decreased significantly,but the level of FTO and other related methylases increased sharply after inflammation,suggesting that the overall level of methylation was increased.Compared with the inflammation group,the inflammation level of the inflammatory group treated with inhibitor increased significantly,and the crypt injury was more serious.The results showed that the increase of RNA m6A methylation level of intestinal organoids in inflammation aggravated the level of inflammation and the damage of intestinal stem cells.3 The mechanism of probiotics in alleviating the intestinal damage of chickens caused by Salmonella typhimurium infectionMicrobiota play an indispensable role in the process of enteritis.As special microbiota beneficial to intestinal health,probiotics play an important role in improving intestinal vitality,resisting pathogenic bacteria invasion,maintaining intestinal barrier and regulating intestinal immune system.In this study,the probiotics from several strains isolated and the probiotics existing on the laboratory were used to screen the excellent probiotics to investigate whether they could improve the chickens enteritis caused by This study also would like to explore the role of probiotics in regulating the methylation level of RNA m6A to improve animal enteritis.This research found that several probiotics had a positive effect on weight of chickens.Under the injury to Salmonella typhimurium,several probiotics strains maintained the intestinal mucosal barrier to a certain extent and alleviated the intestinal damage,and the level of m6A methylation could be regulated by Akkermansia muciniphila.The comprehensive evaluation showed that the effect of Akkermansia muciniphila on intestinal health was better.In conclusion,in order to explore the role of genetic epigenetic modification in the regulation of enteritis,the experiment found that there was a certain relationship between enteritis and methylation.The addition of inhibitor of FTO had no effect on cell activity of organoids and the expression of FTO decreased significantly.The level of FTO and the degree of inflammation increased rapidly after inflammatory injury.At the same time,probiotics which had positive effect on chickens’ weight were screened out,and the role of them in regulating the level of m6A methylation to improve animal enteritis was further explored.The results showed that Akkermansia muciniphila had a positive effect on weight of chickens,reducing the level of m6A methylation and inhibiting the development of inflammation.Therefore,this study further revealed the relationship among probiotics,intestinal immune system,epigenetic modification and enteritis. |
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