Structural shift of gut microbiota during chemo-preventive effects of epigallocatechin gallate on colorectal carcinogenesis in mice

Figure 1 Experimental protocol. Experimental FVB /N mice were divided into three groups, i.e., control group, model group, and epigallocatechin gallate treatment group. Animals in the model and EG groups initially received a single intraperitoneal injection of azoxymethane (AOM: 10 mg/kg). After the AOM administration, mice in the model and EG groups received 2.5% dextran sodium sulfate (DSS) in drinking water for 3 consecutive days. Mice in the EG group also received oral 1% EGCG 20 mg/kg per day for 13 wk. AOM: Azoxymethane; EGCG: Epigallocatechin gallate.

Figure 2 Body weight gain of azoxymethane/dextran sulfate sodium-treated female FVB/N mice.

Figure 3 Chemo-preventive effect of epigallocatechin gallate on colorectal carcinogenesis in azoxymethane/dextran sulfate sodium-treated mice. A and B: Representative hematoxylin and eosin stained histological sections of the control, model, and EG groups. A: × 10; B:× 40; C: Number of colon tumors and tumor load were reduced very significantly in the epigallocatechin gallate (EGCG) group compared to the model group (P < 0.01 and P < 0.001, respectively); D: Representative macroscopic morphology of colon tumors in the model and EG groups. Arrows indicate the azoxymethane/dextran sodium sulfate-induced tumors.

Figure 4 Comparative analysis of alpha diversity at T1 and T2 at the 8^th and 13^th week. ^aP < 0.05.

Figure 5 Statistical analysis for 16 genera (families) at T1 (^aP < 0. 05, NS means no significant differences).

Figure 6 Statistical analysis for Lactobacilli and Bifidobacterium (family) at T2 (^aP < 0. 05, NS means no significant differences).