Table 1.
The Composition of HFD.
Figure 1.
Time course of the experiment and the animal treatment procedures.
STZ was administered as 35 mg/kg, i.p. and DMH was administered as 25 mg/kg/week, i.p. The abbreviations denote STZ: Streptozotocin; DMH: 1,2-dimethylhydrazine; ACF: Aberrant crypt foci.
Figure 2.
Body weight of rats throughout the entire experiment.
Values are expressed as mean ± S.E.M. and analyzed using unpaired student’s T test at P<0.05. At the conclusion of the experiment, *P<0.05 vs. Control group. #P<0.05 vs. DMH group.
Table 2.
Level of blood biochemical indexs.
Figure 3.
Formation of ACF induced by DMH in the rat colon.
Fig. 3A: normal crypt foci (100×). Fig. 3B: Crypt enlargement and deformation (40×). Fig. 3C: ACF formed by 2 aberrant crypts (40×). Fig. 3D: ACF formed by 3 aberrant crypts (40×). Fig. 3E: ACF formed by ≥3 aberrant crypts (40×). Fig. 3F: tumor-like tissue (40×).
Table 3.
DMH-induced ACF in rat colon.
Figure 4.
Tumor tissues obtained from DMH-induced rats.
Fig. 4A: The largest tumor obtained from the STZ+DMH group. Fig. 4B: Several small tumors together isolated from the DMH group. Fig. 4C: Several tumors collected from one rat in the STZ+DMH group. Fig. 4D: Tumor growth in the intestinal lumen interfering with bowel movements, resulting in difficult defecation and building of gas in the intestine in some rats.
Table 4.
Incidence, number and volume of tumors.
Figure 5.
A bar chart demonstrating the proliferation index (PI) of colorectal tumor cells in DMH-induced colon tissues (DMH group and STZ+DMH group).
The PI was expressed as the percentage of PCNA-positive nuclei among the total number of cells counted. Values are expressed as mean ± S.E.M. and analyzed using unpaired student’s T test at P<0.05. *P<0.05 vs. DMH group.
Figure 6.
Bar charts demonstrating the enzyme activities in colon tissues.
No tumor formation was detected in the Control group and STZ group, so dissect the samples at random. Samples were collected from the intratumoral and the peritumoral regions respectively in the DMH group and STZ+DMH group. The activities of hexokinase (HK), pyruvate kinase (PK) and pyruvate dehydrogenase (PDH) in colonic tissues were measured. Values are expressed as mean ± S.E.M. and analyzed using unpaired student’s T test at P<0.05. Fig. 6A: Analysis of HK. *P<0.05 vs. Control group. #P<0.05 vs. Peritumor respectively. $P<0.05 vs. DMH group respectively; Fig. 6B: Analysis of PK. *P<0.05 vs. Control group. #P<0.05 vs. Peritumor respectively; Fig. 6C: Analysis of PDH. *P<0.05 vs. Control group. #P<0.05 vs. Peritumor respectively. $P<0.05 vs. DMH group respectively. Fig. 6D: Analysis of HK, PK and PDH activities at different time course in the STZ+DMH group. *P<0.05 vs. Start point respectively. #P<0.05 vs. STZ injection respectively.