Journal of Lipid Research, Vol 38, 491-502, Copyright © 1997 by Lipid Research, Inc.
Additive hypocholesterolemic effect of psyllium and cholestyramine in the hamster: influence on fecal sterol and bile acid profiles
BP Daggy, NC O'Connell, GR Jerdack, BA Stinson and KD Setchell
Procter & Gamble Company, Cincinnati, OH 45040, USA.
Recent findings suggest that the effects of cholestyramine and psyllium in
combination could be additive for cholesterol-lowering. We therefore
examined the effect of both agents, alone and in combination, on
lipoprotein cholesterol and neutral and acidic steroid excretion in the
hamster. Animals (n = 8/group) were fed for 21 days, either a basal chow
diet supplemented with 10% palm oil and 0.2% cholesterol, or one of four
treatments consisting of the basal diet plus: 5.5% cellulose; 5% psyllium
with 0.5% cellulose; 0.5% cholestyramine with 5% cellulose; or 5% psyllium
with 0.5% cholestyramine. Psyllium and cholestyramine both had significant
hypocholesterolemic effects, but in combination produced additive
reductions in lipoprotein and hepatic cholesterol. Psyllium,
cholestyramine, and the combination increased total bile acid excretion by
26%, 57%, and 79%, respectively. Psyllium affected only unconjugated bile
acid excretion while cholestyramine also increased the excretion of
conjugated and primary bile acids. Neither agent, nor the combination,
affected fecal neutral sterol excretion. We conclude that, while both
agents lower cholesterol by a mechanism of increased bile acid excretion,
these studies indicate that psyllium does not bind bile acids in vivo and
lend further support for the concomitant use of these agents for
cholesterol-lowering.