Influence Of Molar Loss On Cognitive Function And Gut Microbiota In Rats

Objective:This study aims to observe the changes of cognitive function and microbiota in SD rats after molar loss.Methods:Thirty-two SPF 6-week-old male SD rats,weighing 200-300 g,were randomly divided into three groups: bilateral group(bilateral maxillary molars extraction,n=11),unilateral group(unilateral maxillary molars extraction,n=11)and control group(n=10).The tooth loss model was established after the rats were adapted for 1w,and the rats were treated according to the group conditions.Six weeks after the modeling,the rats were trained by FC experimental fear learning,and the cognitive function of each group was detected by FC experiment one week later.After detection,feces samples were collected for 16 Sr RNA sequencing.Results:1.During the experiment,there was no significant difference in body weight among the three groups(P > 0.05).2.The results of sound memory test(conditioned fear level test)showed that compared with the control group,the cognitive function of the rats in the bilateral group was significantly decreased(P < 0.05),but the cognitive function of the rats in the unilateral group was not significantly changed(P > 0.05).Environmental memory test(situational fear level test)showed that there was no significant difference in cognitive function among the three groups(P > 0.05).3.Intestinal microflora test results showed that α diversity index analysis showed no significant difference among the three groups(P > 0.05);Compared with the control group,the relative abundance of Prevotella was significantly decreased(P< 0.05),while the relative abundance of Bacteroides was significantly increased(P <0.05).Compared with bilateral groups,the equal relative abundance of Spironella in unilateral group was significantly increased(P < 0.05);Compared with the control group and unilateral group,the proportion of equal relative abundance of Venococcus in bilateral group was significantly increased(P < 0.05).Conclusion:Bilateral molar loss can cause cognitive decline in rats,and changes in gut microbiota occur in both unilateral and bilateral molar loss groups.There may be a certain correlation between cognitive decline and changes in gut microbiota after molar loss in rats.