Prevention Of Colorectal Cancer By Lactobacillus Acidophilus In Gut Microbiota

Purpose: To evaluate the effect of Lactobacillus acidophilus CGMCC 878 on the inhibition of development and progression of chemically induced(1,2dimethylhydrazine hydrochloride) colorectal tumor in rats via change in the intestinal microbiota.Method: Male Sprague dawley rats were received Azithromycin gavage in the beginning once dose daily for five days and divided into 4 groups, as the following, G1 Normal group was subcutaneously injected with EDTA-saline, G2. DMH only group was subcutaneously injected carcinogen alone(DMH) 30mg/kg, G3 short-term-L.A group(pre- L.A) was received L. acidophilus CGMCC 878 gavage once daily for 2weeks then started to give subcutaneous carcinogen injection(DMH), and G4 long-term- L.A group(32weeks-L.A) was received L. acidophilus CGMCC 878 gavage once daily from beginning the experiment until 32 weeks and also given subcutaneous carcinogen injection(DMH) for 22 weeks. Thus, a various comparison of the microflora was analysis by using PCR-DGGE technique. At finally, bacteria species have identified by cloning sequencing.Result: The rats received DMH + long-term Lactobacillus acidophilus CGMCC 878 have significantly reduce of total number of tumor about(64.25 %), the Total amount of 16 s r RNA gene was more in carcinogen group and also the number of bands that was detected in DMH treated group(25.20±2.573) was more than other groups(long-term L.A treated(19.20±2.616), short-term L.A(20.30±3.368) as well as Normal group(23.30±3.659). Observed also decreased the bacterial composition such as Mycoplasma leachii. Ruminococcus obeum, Clostridium thermocellum, and also significant decreased fecal β-glucuronidase activity in compared with DMH only group.Conclusion: long-term Administration of L. acidophilus CGMCC 878 can decrease the development of the colorectal tumor in the rats through alteration of intestinal microbiota by decrease of pathogenic bacteria, and increase of beneficial bacteria like Lactobacillus, as well as reduce activity of bacterial Enzyme β-glucuronidase These observations suggest that Lactobacillus acidophilus CGMCC 878 may have therapeutic potential in attenuation of carcinogenesis in GI tract.