Effect Of Phlegm Syndrome On The Incidence Rate Of Colorectal Cancer In Mice Based On The Abnormal Cholesterol-bile Acid Metabolism

Objective: this study aimed to study the relationship between the disturbance of intestinal flora caused by abnormal cholesterol-bile acid metabolism and the induction of phlegm on the occurrence and development of colorectal cancer.Methods: the model of phlegm syndrome of colorectal cancer was induced by high fat diet and AOM / DSS "four steps" in animal experiment.The different characteristics of intestinal microflora were dynamically compared in control group(CG),phlegm syndrome group(PSG),CRC group(CRCG),phlegm with CRC group(PCRCG)and Erchen decoction group(ECG).the general conditions of mice at the 6th,12 th,18th and 24 th week were observed,and the feces of mice in each group were collected for 16 S r RNA detection.At the end of the 6th,18 th and 25 th week,the blood lipid biochemical and total bile acid levels in each group were detected after the mice sacrificed.The colorectal length,tumor size and number,liver index and spleen index were calculated.Paraffin sections of liver and colon were stained with HE staining for morphological observation.The expression of LXR,FXR,CYP7A1 and β-catenin in the tissues in each group were detected by q PCR and Western blot in m RNA and protein expression levels were measured,while the correlation between the m RNA expression levels of LXR,FXR,CYP7A1 and β-Catenin and the different intestinal flora were analyzed.Results: the tumor incidence and the average tumor size of PCRCG group were higher than those in other CRC groups.Erchen decoction affected the incidence of colorectal cancer in mice,and the incidence of tumor in ECG group was significantly lower than that of other CRC groups.The total cholesterol of mice was significantly different in the 6th,18 th and 25 th weeks,and the serum cholesterol content in PSG group was significantly higher than that of other groups,followed by PCRCG group,while there was no difference between the CRCG group and the CG group.The change trend of HDL and LDL was consistent with cholesterol.Meanwhile,at the 18 th week,the triglyceride of the CRCG group was significantly higher than other groups,while there was no difference between CRCG group and PCRCG group.There was no statistical difference in total bile acid in serum at 18 weeks,and PSG group was significantly higher in the 25 th week than in other groups.The structure and abundance of intestinal flora in PSG group and ERG group were significantly different.The high fat diet changed the ecological environment of intestinal microorganism continuously,and the different levels of intestinal bacteria in different groups related to bile acid metabolism were different.The expression of LXR m RNA in the liver of the other groups were lower than that of the CG group,and there were significant differences among those groups.The level of LXR in CRCG group was the lowest,while the protein expression level of LXR in ECG group was the highest,and other groups were higher than that of the CG group.The m RNA expression of CYP7A1 in CRCG group was significantly higher than that in other groups,followed by ECG group,and there was no difference between PSG group and PCRCG group.The protein expression of CYP7A1 in PCRCG group,ECG group and PSG group were higher than that in CG group and CRCG group.The expression of FXR m RNA was the highest in PCRCG group,and the lowest in phlegm resolving CRCG group.The lever of m RNA and protein expression of β-catenin in CG group and PSG group were higher than those in the other three groups,and the expression level in PCRCG group was the lowest.In colon tissues,the expression of FXR m RNA decreased in CRCG group,PCRCG group and PSG group,while the protein lever expression of FXR decreased in PCRCG group,ECG group and PSG group.The expression of β-catenin m RNA decreased in CRCG group,PCRCG group and PSG group,while the protein expression increased in CRCG group,PCRCG group and PSG group.The m RNA expression of LXR in CRCG group,PCRCG group and ECG group decreased,while the protein expression in PCRCG group,PSG group and ECG group decreased compared with CG group.The m RNA expression of CYP7A1 was the highest in PCRCG group,and increased in PSG group.Conclusion:(1)phlegm induced by high-fat diet can induce colorectal cancer in mice,and its mechanism is related to abnormal metabolism of cholesterol-bile acid.(2)Erchen decoction intervention can significantly reduce the incidence of colorectal cancer in mice fed with high-fat diet.Erchen decoction can alleviate the occurrence and development of phlegm syndrome CRC.(3)Erchen decoction can improve the intestinal flora structure of CRC mice fed with high-fat diet,and the changes tend to the structure of mice fed with normal diet.The ratio of Firmicutes/Bacteroidetes in high-fat diet groups was greater than 1,and the ratio of Firmicutes/Bacteroidetes was decreased by resolving phlegm.(4)FXR and CYP7A1 play an important role in the relationship between the abnormal metabolism of cholesterol-bile acid and the progress of sputum induced colorectal cancer.