Objective To explore the characteristics of the intestinal flora of atherosclerosis model mice

the content of the metabolite trimethylamine oxide（TMAO）

the cardiac function level

and the correlations among them. Methods Ten ApoE

-/-

mice were fed with high-fat diet for 12 weeks to establish the atherosclerosis model

and another 10 C57 BL/6/J mice were set as the normal group. The small animal ultrasonic detector was used to assess the cardiac function including left ventricular ejection fraction（LVEF） and left ventricular fractional shortening（LVFS）; automatic biochemical analyzer was used to detect the content of serum total cholesterol（TC）

triglyceride（TG）

high-density lipoprotein cholesterol（HDL-C） and low-density lipoprotein cholesterol（LDL-C）; Oil Red O staining was used to assess the lipid deposition of aorta; high-performance liquid chromatography-mass spectrometry（LC/MS） method was used to detect the plasma TMAO level; 16 SrDNA high-throughput sequencing technology was used to analyze the characteristics of intestinal flora. The correlations among the dominant bacteria in the mice intestines

the TMAO level and the cardiac function in the model group were analyzed with Spearman correlation coefficient method. Results Compared to the normal group

the model group had significantly lower levels of LVEF and LVFS

higher levels of serum TG

TC and LDL-C

and lower HDL-C level（P

<

0.05）. In the model group

the deposition of aorta lipid was obvious; the plasma TMAO level was significantly increased（P

<

0.05）; the abundance of Lachnospiraceae

N

K4 A136

g

roup

Rosella

Lachnoclostridium

Enterobacter

and Eubacterium in the intestinal flora were significantly increased

while the abundance of Prevotella was significantly reduced（P

<

0.05 or P

<

0.01）. The results of correlation analysis showed that the dominant bacteria genus Lachnoclostridium was positively correlated with the TMAO level

and the TMAO level was positively correlated with LVEF and LVFS（P

<

0.05）. Conclusion In mice model of atherosclerosis

the intestinal flora is disturbed and the metabolite TMAO increased

suggesting that the diversity of flora changes

the plasma TMAO level and the cardiac function seem to be correlated.