Effect Of Lactobacillus Plantarum BSGP201683 On Intestinal Microflora And Immune Response In Giant Panda Flora-associated Mice

Gastrointestinal diseases seriously affect the health of captive and wild giant pandas(Ailuropoda melanoleuca).The research and development of the functional probiotics of the giant panda has important significance and value,in theoretical research and practical application,in protecting the health of the giant panda.We have obtained a potential probiotic strain,Lactobacillus plantarum BSGP201683(L.plantarum G83),isolated from the feces of health giant panda.The microbe survived well at low p H,was tolerant to high bile-salt concentrations,and resistant to antibiotics and pathogenic bacteria.And it has been proved that the microbe also could effectively improve the intestinal microflora,intestinal barrier and attenuate inflammation of mice.This study aimed to evaluate the probiotic effect of L.plantarum G83 in the model of the feces of giant panda transplating to the gut of mice,using the feces of health giant panda,feces microbiota transplation and pseudo mice.To evaluate the model,we analyzed the fecal microflora structure similarity between mice of the model and giant panda by using the PCR-DGGE and qPCR.Mice were treatmented with antibiotic(Vancomycin,Neomycin and Omeprazole)3 d,and orally administrate the bacteria suspension of panda feces 3 d.The results showed that,in the feces of the model mice,the number of Enterococci decreased significantly,Firmicutes,Fusobacterium XIVa,Lactobacillus group and Ruminococcus increased significantly,total bacteria,Bacteriidetes,Enterobacteriaceae family and Bifidobacterium spp.had no significantly change.Cluster analysis of feces flora in panda and model mice was 0.47.These results demonstrated the gut microflora of the model mice could represent panda gut in some extent,and indicated the experimental results in the giant panda.To evaluate the probiotic effects of L.plantarum G83,isolated from giant panda feces,on the model mice when ETEC invasion.Each group was given different treatments as follows:(1)oral administration of sterile PBS 18 d(PFMT);(2)oral administration of L.plantarum G83 15 d and sterile PBS 18 d(PFMT-G);(3)oral administration of L.plantarum G83 15 d and challenge with ETEC 3 d(PFMT-GE);(4)oral administration of sterile PBS 15 d and challenge with ETEC 3 d(PFMT-E).Ileum histopathology,the expression of cytokine and tight-junction protein,and the change of fecal flora were detected.The results demonstrated that after ETEC invasion,compared with PFMT,the number of total bacteria and Bacteroidetes was significantly increased in PFMT-G,PFMT-GE and PFMT-E;the number of Firmicutes in PFMT-GE was significantly higher than PFMT-G;the number of Fusobacterium XIVa in PFMT-GE and PFMT-E was significantly higher than PFMT-G;the level of Enterobacteriaceae family in PFMT-GE and PFMT-E was significantly higher than PFMT and PFMT-G;the level of Enterococci in each groups was no significant difference;the content of Lactobacillus group in PFMT-G was significantly higher than PFMT,PFMT-GE,PFMT-E;the content of Bifidobacterium spp.in PFMT-G and PFMT-GE was significantly higher than PFMT;the level of Ruminococcus in PFMT,PFMT-GE,and PFMT-E was significantly higher than PFMT-G.Administrating with L.plantarum G83 could improved sigmificantly the number of Lactobacillus group,Bifidobacterium spp.,Bacteroidetes,and decreased sigmificantly the number of Fusobacterium XIVa,Enterobacteriaceae family,Ruminococcus.It also could increase the secretion of tight junction protein and cytokines in the intestinal tract and participate in and promote the development of inflammation.These results suggest that L.plantarum G83 could improve the intestinal microecology of the model mice,and have immune regulation effect on its intestinal immunity.