Effects Of Maternal Diet On Intestinal Mucosal Flora And Susceptibility To Colitis In Offspring Mice

Objective: To investigate the effects of different diets in early life on the intestinal mucosal flora of mice and their susceptibility to colitis in adults.Methods: The experimental animals were 8-week-old C57BL/6 mice of SPF(specific pathogen free)grade.All experimental mice were labeled with ear markers.1)Male and female mice bred in cages in the ratio of2:1.After confirmed pregnancy,pregnant female mice were randomly selected into three groups: high fat diet group,high protein diet group and normal diet group.During pregnancy and lactation,the female rats were given high fat diet,high protein diet and normal diet respectively.2)After weaning(at its 3 weeks old),the offspring mice of the maternal high fat diet group were randomly divided into two groups: continuing high-fat diet / returning to normal diet.The offspring mice of high protein diet group were also randomly divided into two groups: continuing high protein diet / returning to normal diet.The offspring mice of the normal diet group continued to normal diet until the age of 8 weeks.3)Each group of the remaining offsprings were randomly divided into two subgroups at 8 weeks and 1 day old.They were given dextran sulfate sodium(DSS)drinking water or normal drinking water for 7 days until 9weeks old.During the whole experiment,the animal feeding environment temperature was 22 ～ 24℃,and the environmental humidity was 40 ～70%.The feeding,feces,body weight and survival of offspring at its 3weeks old,8 weeks old and 9 weeks old were all recorded.When 3 weeks old and 8 weeks old,6 mice of each group were randomly selected,and their colon tissue was left for 16 srna flora analysis.The disease activity,colon histopathology and pathological inflammation of the 9-week-old mice in each group were evaluated.Results: 1)during weaning,there was no significant difference among each group in body weight,colon appearance and length.Among the 8-week-old offspring mice,the body weight of the high fat diet with maternal high fat diet group increased(P < 0.05).The body weight of the high protein diet with maternal high protein diet group decreased(P <0.05).There was no significant difference in colon appearance and length between the 8-week-old mice groups.2)After DSS intervention,the disease activity index(DAI)score of the high fat diet mice with maternal high fat diet group was significantly higher than that of the control group,but there was no significant difference in colitis pathological inflammation index;The DAI score of the high protein diet mice with maternal high protein diet group increased significantly after weaning,and the pathological inflammation index of colon also increased significantly.3)Compared with the control group of the same age,the number of species and the αdiversity decreased significantly(P < 0.05).Among the 8-week-old offspring mice with maternal high protein diet,the mice continuing to high protein diet earn the decreased αdiversity(P <0.05),while the αdiversity of the returning to normal diet mice were no difference to the control group.On the other hand,when weaning,theβdiversities the maternal high fat diet group(P < 0.05)and maternal high fat diet group(P = 0.07)were lower than that of the normal diet group,but there was no significant difference between 8-week-old mice.In the age of 3 weeks,compared to the maternal normal control group,there were some bacterial groups of maternal high protein diet group were reduced,including probiotics like Lactobacillus.Conclusion: maternal high protein diet in early life can negatively regulate the diversity of intestinal flora in offspring mice,including the reduction of Lactobacillus,and help to improve the susceptibility to colitis in their adulthood.