Protective Effect Of Microbial Merment On Gut Barrier Under Methylprednisolone

Abstract Aim Although transplantation has got great success , infection is still one of the major complications during solid organ transplantation,the most common pathogen about solid organ transplantation was bacterial and the major infection during the first month of transplantation was bacterial too. Among them the abdomen infection were caused manily by intestinal pathogen such as E .coli , enterococcus, yeast, et al. The purpose of this experiment was to investigate ①the changes of gut barrier under methylprednisolone for example its permeability and bacterial translocation , ②the protective effect of microbial ferment on the changes, so as to provide evidence for the prevention and therapy of gut-derived inflammation during transplantation. Methods 84 healthy male Wistar rats were divided randomly into control group, MeP(methylprednisolone) group and MiF(microbial ferment) group,then according to 0,3,5,7day each group were divided into four subgroups each subgroup contain 7 rats,the control rats were not given methylprednisolone and microbial ferment, MeP rats were injected methylprednisolone into abdomen cavity 100mg/kg each day, MiF rats were given both methylprednisolone the same amount and way as MeP rats and microbial ferment 6g/kg perfus stomach 1 time each day. All the animals were anesthetized by 2% pentobarbital, abdominal aorta blood were taken out under sterile condition, then parts of lung,liver,spleen ,mesenteric lymph node,ileum and ileum content were removed for measure。Brandt`s method was used to measure D-lactic,Li Junyou`s way was for blood DAO,BD company`s flow cytometer and Annexin-V were used to assay the apoptosis of mesenteric lymph node lymphocyte,bacterial culture were used to detect bacterial translocation at the organs and intestinal microecosystem, PCR was used to detect special bacterial gene segment,pathology was used to find the changes of digestive tract mucous membrane villus。Results Compared with control group, D-lactic in MeP group turned to much higher(p<0.01or p<0.05) than that in control group at the latter 3 time points;DAO in MeP group increased significantly (p<0.01or p<0.05) than that in control group at the latter 3 time points;gut flora didn't change much(p>0.05) compared with that in control group;the apoptosis of mesenteric lymphocyte in MeP group increased significantly(p<0.01) than that in control group;bacteria culture in MeP groups organs at 7days was higher than that in control group(p<0.05);positive rates of special bacterial gene parts in MeP groups were higher than that in control groups; pathological examination showed intestinal villus to be shallow,scattered and rough in Mep groups。At each time point compared with MeP group, D-lactic in MiF group at 7 day turned to much lower(p<0.01);Gut Bifidobacterium(TPY) and Yeast(MRS) increased significantly at 5,7day(p<0.05 or p<0.01);The apoptosis of mesenteric lymphocyte at 3,5 day was much lower(p<0.01 or p<0.05);bacteria culture of organs in MiF groups a little lower than that in MeP; positive rate of enterogenic bacterial gene segment were lower in MiF groups than that in MeP group; and the digestive tract mucous membrane villus in MiF groups showed tidier,smoother and higher than those in MeP rats. Conclusions Methylprednisolone could damage intestinal barrier and result in its permeability increased,accordingly higher D-lactic in the plasma and bacterial translocation, this maybe one of the reasons that the usage ofglucocorticoid can cause gut-derived infection; Microbial ferment could reduce this kind of damage by improving microecology of intestinal barrier and immunological barrier to decrease its permeability , that can decrease bacterial translocation and the happening of infection in a way.