TY - JOUR
T1 - Cholesterol-lowering action of psyllium mucilloid in the hamster
T2 - Sites and possible mechanisms of action
AU - Turley, Stephen D.
AU - Daggy, Bruce P.
AU - Dietschy, John M.
N1 - Funding Information:
From the Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX; and the Miami Valley Laboratories, Procter & Gamble, Cincinnati, OH. Supported in pati by a research grant from the Procter & Gamble Company and by US Public Health Service Research Grant No. HLO9610 and a grantf rom the Moss Heart Fund. Address reprint requests to Stephen D. Turk-y, PhD, Department of Internal Medicine, Universiw of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75235-8887. Cop,vtight 0 1991 by U! B. Saunders Cornpan) 0026049519114010-0013$03.00/0
PY - 1991/10
Y1 - 1991/10
N2 - These studies were undertaken to examine and compare the metabolic effects of psyllium mucilloid and two other nonabsorbable polymers (cholestyramine and surfomer) on sterol metabolism in the hamster. These three agents all significantly lowered the plasma total cholesterol concentration and the level of cholesterol carried in low-density lipoproteins (LDL). Rates of cholesterol synthesis were markedly increased in the livers of the psyllium-fed animals, but not in other tissues. In contrast, cholestyramine and surfomer feeding increased both hepatic and intestinal sterol synthesis. When cholesterol and saturated triacylglycerols were added to the diet, psyllium feeding essentially completely blocked the increase in the plasma cholesterol concentration and hepatic cholesterol content and the suppression of cholesterol synthesis. The pool of bile acid in the small intestine was increased from the control value (17.9 μmol/animal) by both psyllium (23.0 μmol) and cholestyramine (21.9 μmol) feeding. However, this pool was readily absorbed and secreted into the bile in the psyllium-fed animals ( 27.9 μmol 4 h), but not in the cholestyramine-treated hamsters ( 13.0 μmol 4 h). This was consistent with the further observation that there was no binding of bile acid by psyllium under in vitro conditions. Thus, these findings indicate that all three polymers lower plasma cholesterol concentrations by inducing a net negative cholesterol balance across the liver. With psyllium, this effect is presumably articulated through a reduction in cholesterol absorption, as well as an increase in the rate of degradation of cholesterol to bile acids.
AB - These studies were undertaken to examine and compare the metabolic effects of psyllium mucilloid and two other nonabsorbable polymers (cholestyramine and surfomer) on sterol metabolism in the hamster. These three agents all significantly lowered the plasma total cholesterol concentration and the level of cholesterol carried in low-density lipoproteins (LDL). Rates of cholesterol synthesis were markedly increased in the livers of the psyllium-fed animals, but not in other tissues. In contrast, cholestyramine and surfomer feeding increased both hepatic and intestinal sterol synthesis. When cholesterol and saturated triacylglycerols were added to the diet, psyllium feeding essentially completely blocked the increase in the plasma cholesterol concentration and hepatic cholesterol content and the suppression of cholesterol synthesis. The pool of bile acid in the small intestine was increased from the control value (17.9 μmol/animal) by both psyllium (23.0 μmol) and cholestyramine (21.9 μmol) feeding. However, this pool was readily absorbed and secreted into the bile in the psyllium-fed animals ( 27.9 μmol 4 h), but not in the cholestyramine-treated hamsters ( 13.0 μmol 4 h). This was consistent with the further observation that there was no binding of bile acid by psyllium under in vitro conditions. Thus, these findings indicate that all three polymers lower plasma cholesterol concentrations by inducing a net negative cholesterol balance across the liver. With psyllium, this effect is presumably articulated through a reduction in cholesterol absorption, as well as an increase in the rate of degradation of cholesterol to bile acids.
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U2 - 10.1016/0026-0495(91)90131-F
DO - 10.1016/0026-0495(91)90131-F
M3 - Article
C2 - 1943733
AN - SCOPUS:0026093637
SN - 0026-0495
VL - 40
SP - 1063
EP - 1073
JO - Metabolism
JF - Metabolism
IS - 10
ER -