[Effects of different feeds on intestinal microbiota and fat deposition in rats colonized with normal triglycerides...

To study the changes in intestinal microbiota, intestinal microbiota and fat deposition in rats with normal triglyceride(TG) colonization under different feed conditions.

10-week-old male sterile SD rats were randomly divided into 2 groups according to body weight, with 6 rats in each group, namely the high-fat diet group and the normal diet group. Rats were given fecal bacterial solution by gavage at a dose of 1 mL/100 g of body weight, every other day, for a total of 3 times, followed by 2 weeks of adaptive growth of the microbiota. After the transplantation was completed, the rats were respectively fed with high-fat diet and normal diet for 9 weeks. Their body weight was weighed every week, and feces were collected every 3 weeks. At the end of the experiment, the rats were sacrificed, and the liver, perirenal fat, subcutaneous fat and brown fat were weighed. Oil red O staining and lipid biochemical index detection were performed on the liver, and high-throughput sequencing was used to analyze the changes in intestinal microbiota of the rats.

After the experiment, compared with the normal feed group, the final body weight, perirenal fat and subcutaneous fat of rats in the high-fat feed group all increased significantly(P<0.05). The serum total cholesterol(TC)and the low density lipopro-tein cholesterol(LDL-C)level was extremely significantly increased(P<0.01). Obvious lipid deposition can be seen in the liver.16 S RNA sequencing analysis of the intestinal microbiota revealed that there were differences and changes in the diversity of Alpha and Beta of the intestinal microbiota, as well as the types and quantities of the microbiota in the high-fat diet group compared with the normal diet group. From the perspective of the phylum level analysis, the abundance of Bacteroidetes in the high-fat feed group decreased from 63.59% at week 0 to 30.94% at week 9, the abundance of Firmicutes decreased from 30.57% to 25.08%, and the F/B value increased from 0.48 at week 0 to 0.81 at week 9. At the genus level, after a 9-week feeding cycle, the abundance of Prevotella＿9 and Phascolarctobacterium in the intestinal tract of rats in the high-fat diet group decreased. The abundance of pathogenic bacteria such as Parabacteroides has increased.

In normal TG population rats with colonized intestinal flora, significant changes occurred in lipid metabolism and the composition of intestinal flora under different feeds.