High Doses of Copper and Mercury Changed Cecal Microbiota in Female Mice.

The aim of the present study was to investigate the effects of high doses of copper (Cu) and mercury (Hg) on the cecal microbiota in female mice. Forty-eight Kunming mice were randomly divided into the control group (CCk group), the Cu group (CCu group), the Hg group (CHg group), and the Cu + Hg group (CCH group). At the 90th day, cecal tissues were prepared for histopathological analysis and cecal contents for analysis by 16S rRNA sequencing method. Cecal tissues from treatment groups had histopathological lesions including increased thickness of inner muscularis and outer muscularis, widened submucosa, decreased goblet cells, mild to moderate necrosis of enterocytes, blunting of intestinal villi, and severe atrophy of central lacteal. Furthermore, compared to the CCk group, the abundance of bacteria genera Rikenella, Jeotgailcoccus, and Staphylococcus were significantly decreased, whereas the bacteria genus Corynebacterium was significantly increased in the CCu group. The abundance of bacteria genera of Sporosarcina, Jeotgailcoccus, and Staphylococcus were significantly decreased in the CHg group and CCH group. The bacteria genus Anaeroplasma was significantly increased in the CCH group. The results indicated that high doses of Cu and Hg caused histopathological lesions and changed the diversity of microbiota in the cecum of female mice, which provide a theoretical basis for more accurate assessment of the risk in intestinal diseases caused by Cu and Hg.