Effect of dietary squalene on the fecal steroid excretions and the lipid levels of serum and the liver in the rat

Abstract

Effects of squalene on serum and hepatic lipid contents and fecal steroid excretion were examined in rat by chronic (0.01-0.1 mL/day, i.e. 8.622-86.22 mg/day) or single (0.1 mL/day, i.e. 86.22 mg/day) oral administration of squalene. With chronic administration of squalene, serum total, HDL-cholesterol, triglycerides and squalene did not change whereas serum phospholipids decreased with 0.1 mL/day of squalene administration. Hepatic total cholesterol and squalene did not changed. Fecal excretion of neutral steroids and bile acids were enhanced in the rats administered 0.1 mL/day of squalene. With single oral administration of squalene, the highest concentrations of squalene and cholesterol were observed at 6 hours in serum, and at 4 and 8 hours, respectively in the liver after squalene administration. Squalene was excreted into feces 35.1%, 6.8% and 0.42% of the administered dose at 0–1, 1–2 and 2–4 days, respectively. Neutral steroid excretion did not change though coprostanol excretion dereased significantly at 0–2 days. Bile acid excretion increased significantly at 1–2 days without change in cholic acid/chenodeoxycholic acid ratio. Oral administration of squalene have no effect on serum and hepatic lipids, but increased fecal bile acids and neutral steroid excretions.