A multimineral natural product from red marine algae reduces colon polyp formation in C57BL/6 mice

Abstract

The goal of this study was to determine if a multimineral natural product derived from red marine algae could reduce colon polyp formation in mice on a high-fat diet. C57BL/6 mice were maintained for up to 18 mo either on a high-fat "Western-style" diet or on a low-fat diet (AIN 76A), with or without the multimineral-supplement. To summarize, colon polyps were detected in 22 of 70 mice (31%) on the high-fat diet but in only 2 of 70 mice (3%) receiving the mineral-supplemented high-fat diet (P < 0.0001). Colon polyps were detected in 16 of 70 mice (23%) in the low-fat group; not significantly different from high-fat group but significantly higher than the high-fat-supplemented group (P = 0.0006). This was in spite of the fact that the calcium level in the low-fat diet was comparable to the level of calcium in the high-fat diet containing the multimineral-product. Supplementation of the low-fat diet reduced the incidence to 8 of 70 mice (11% incidence). Taken together, these findings demonstrate that a multimineral natural product can protect mice on a high-fat diet against adenomatous polyp formation in the colon. These data suggest that increased calcium alone is insufficient to explain the lower incidence of colon polyps.

Figures

Figure 1

Experimental design.

Figure 2. Colon polyp formation in mice; Effects of time, gender and presence or absence of the multi-mineral natural product

Data are based on stereo-microscopic identification. At 5 and 12 months, there were 10 males and 10 females per group. At 18 months, the total number of animals per group was 15 males and 15 females. When findings from the three time-points were analyzed together (Fisher Exact Test), polyp formation was greater in female mice than in males (p

Figure 3. Stereomicroscopic and histological appearance of colon

Upper panels: Normal colonic mucosa; Middle panels: mucosal adenoma; Lower Panels: Adenocarcinoma of colon. Both tumors were from female mice on HFWD. (Histology: hematoxylin and eosin; bar = 100 μm).

Figure 4. Stereomicroscopic and histological appearance of three extra-colonic lesions

Upper panels: mucosal polyp (adenoma) in stomach. Middle panels: mucosal polyp (adenoma) in duodenum. Lower panels: Inflammatory cell nodule (lymphoma) on the serosal surface of ileum. (Histology: hematoxylin and eosin; bar = 200 μm).

Figure 5. Calcium levels in serum and bone

Serum calcium values are means and standard deviations. For bone calcium measurements, bones from all mice in a group were pooled to provide a single value.