Effects Of Sodium Butyrate On Intestinal Flora And Fecal Metabolites In Heat-stressed Mice

The purpose of this study was to investigate the effect of sodium butyrate on the structure of intestinal flora and fecal metabolites in mice with acute heat stress.Thirty30-week-old Kunming mice weighing approximately 20 ± 2 g were randomly divided into a control group(Con),a heat stress group(HS),and a sodium butyrate treatment group(Heat stress+ Sodium butyrate,HSBU)with 10 in each group.The mice in the Con group were raised at room temperature of 23 ± 2°C;the HS group and the HSBU group were subjected to cyclic heat stress treatment(33 ± 1°C,7: 00-19: 00);while the mice in the HSBU group were given 50 mg / kg *BW(body weight)sodium butyrate,mice of HS group and Con group were given an equal volume of saline;observe and record the state of the mice on the 8th day of the experiment,weigh them,collect their feces for 16 Sr DNA high-throughput sequencing and GC-TOF./LC metabolomics analysis,the results are as follows:1.Compared with the control group,the number of intestinal flora OTU in the heat stress group;the alpha-related index Chao1,Ace,and Shannon index values decreased significantly(P<0.05),and the Simpson index value increased significantly(P<0.05);multivariate statistical analysis found that the microbial abundance of Bacteroidetes increased significantly in the heat stress group,while the abundance of Firmicutes decreased significantly(P<0.05).In the heat stress group,the abundance of Erysipelotrichaceae,a group of inflammation-related bacteria in the intestinal flora,increased,the abundance of Lachnospiraceae decreased2.Compared with the control group,the levels of 16 metabolic molecules such as methylmalonic acid,L-tryptophan,and taurine in the feces of the heat stress group increased significantly(P<0.05);The levels of 12 metabolic molecules such as leucine,pantetheine and inosine decreased significantly(P <0.05 or P<0.01).3.Compared with the heat stress group,the sodium butyrate can increase the relative abundance of Firmicutes and the protective intestinal commensal bacteria Lachnospiraceae,and The genus abundance of the short-chain fatty acid producing bacteria such as Ruminococcus＿1,Roseburia and Anaerotruncus were significantly increased(P<0.05 or P<0.01)and the abundance of the genus Erysipelotrichaceae was significantly reduced(P <0.01).4.Compared with metabolite level in heat stress group,the sodium butyrate group can reduced the level of specific elevated metabolites such as L-pyridine,L-ascorbic acid,and adjusted the metabolite disorder caused by heat stress.5.Correlation analysis of different intestinal microflora in mice and different metabolites in feces found that metabolites such as L-ascorbic acid,creatinine,L-piperidine showed a positive / negative correlation with Lachnospiraceae,Micrococcaceae,Rhodobacteraceae and Tannerellaceae(P> 0.05 or P <0.05),and further studies found that metabolic differences(correlation)are involved in the metabolism of arginine and proline in the organism,microbial metabolism in different environments and hypoxia-inducible factor 1(HIF-1)Signal pathways and other metabolic pathways.To sum up,heat stress will destroy the intestinal microbes and metabolic function of mice,and infusion of sodium butyrate can adjust the structure and metabolites of heat stress mice intestinal flora to relieve heat stress.This may be related to the HIF-1 signaling pathway,which deserves further study.