Article Figures & Data
Figures
- Figure 1.
Experimental protocol to evaluate chemopreventive activity in F344 rats. Rats were divided into two control (untreated and treated) groups and four experimental groups. The rats were fed a control diet (AIN-76A) or diet supplemented with different doses of Capsosiphon fulvescens (1 or 2%) and Hizikia fusiforme (2 or 6%), for the 11-week experimental period. Rats in groups 2-6 received subcutaneous injections of azoxymethane (AOM; 15 mg/kg body weight) once a week for 2 weeks. Group 1 served as an untreated control (1 ml saline/kg by subcutaneous injection + control diet) and group 2 served as the treated control (15 mg AOM/kg body weight by subcutaneous injection + control diet).
- Figure 2.
Histopathological examination of colonic tissues of F344 rats from group 1, saline + control diet (A); group 2, azoxymethane (AOM) + control diet (B); group 3, AOM + 1% Capsosiphon fulvescens-supplemented diet (C); group 4, AOM + 2% C. fulvescens-supplemented diet (D); group 5, AOM + 2% Hizikia fusiforme-supplemented diet (E); and group 6, AOM + 6% H. fusiforme-supplemented diet (F). Representative microscopic examination was performed with hematoxylin and eosin staining. Histological assessment showed the presence of aberrant crypt foci including dysplasia and hyperplasia, abnormally-shaped lumens and elongated nuclei in the colonic mucosa of the treated control group but a marked reduction in all experimental groups. Sections were examined at 200× magnification.
- Figure 3.
Histopathological sections, stained with methylene blue to identify crypts in the colonic tissues of F33 rats, and examined at 200× magnification. In group 1, we did not find formation of any aberrant crypt foci (ACF), while group 2 had the highest number of ACF; with groups 3-6 having significantly fewer crypts after dietary supplementation with different doses of Capsosiphon fulvescens (1 or 2%) or Hizikia fusiforme (2 and 6%), respectively. Arrows indicate ACF.
- Figure 4.
Immunohistochemical analysis of proliferating cell nuclear antigen (PCNA) in colonic tissue of F344 rats from groups 1-6. In group 1, we observed PCNA-negative cells (blue color); in group 2, we found PCNA-positive cells (brown color); but experimental groups 3-6 had fewer PCNA-positive cells than the treated controls (group 2). Colonic tissues were examined at 200× magnification.
- Figure 5.
Proliferating cell nuclear antigen (PCNA) labeling index (%) of colonic mucosa in F344 rats. Group 1 was the untreated control, group 2 had the highest index, while groups 3-6 demonstrated the significant inhibitory effect of dietary Capsosiphon fulvescens (**p<0.01) and Hizikia fusiforme (*p<0.05) on PCNA labeling index compared to group 2. The data represent the mean±standard error of the mean.
