Dietary chitosan improves hypercholesterolemia in rats fed high-fat diets.

The hypolipidemic mechanism of chitosan was investigated in male Sprague-Dawley rats. Animals were divided into 5 groups (n = 8): a normal fat control group, a high-fat control group (HF), a positive control group (CR), and 2 chitosan groups (CIS1 and CIS2). Chitosan was fed at the beginning (CIS1) and after 2 weeks (CIS2). A commercial diet with 5% (wt/wt) cellulose (HF), cholestyramine (CR), or chitosan (CIS1, CIS2) was fed for 6 weeks. Chitosan did not affect food intake but decreased body weight gain and significantly increased fecal fat and cholesterol excretion, reduced the lipid level in plasma and liver, increased liver hepatic and lipoprotein lipase activities compared with HF (P < .05), and tended to relieve the degenerated fatty liver tissue. No significant differences in all measurements were found between the CIS1 and CIS2 groups although the CIS1 rats exhibited lower lipid levels compared to those in the CIS2 group. The results suggest that chitosan reduced the absorption of dietary fat and cholesterol in vivo and could effectively improve hypercholesterolemia in rats.