Effect of dietary fiber on the prevention of liver lipid accumulation induced by high polyunsaturated oil

This study investigated whether dietary fiber can prevent the accumulation of liver lipids due to the ingestion of polyunsaturated oil. Fifteen percen t fish oil (FO) was added to the basal diet as a source of polyunsaturated oil. Ten percent cellulose, pectin, guar gum, konjac mannan or gum Arabic w as mixed in the diet as a source of dietary fiber. Commercial Purina rat ch ow was used as a control and a fiber-free (blank) diets were also employed in the study. Each experimental diet was fed to each group of 6 Wistar rats for 8 weeks. Fish oil feeding lowered the plasma triacylglycerols (TG) and cholesterol (CS) levels. Rats fed a fiber-free diet had higher liver weigh ts indicating hepatomegaly and a marked accumulation of liver lipids. With the exception of cellulose and gum Arabic, the inclusion of dietary fiber i n FO diets lowered the plasma total lipids and CS, plasma TG was unchanged. Pectin and guar gum enhanced the CS-lowering effect of the FO diet. All of the test fibers, but especially pectin and guar gum, reduced the accumulat ion of total lipids, TG and CS in rat fiver caused by dietary FO. Hepatic g lucose-6-phosphate dehydrogenase activity was reduced in rats fed FO, but d ietary fiber had no effect on the activity of this enzyme.