Biliary and fecal steroid excretion in rats fed partially hydrogenated soybean oil

Abstract

Male Wistar rats were fed cholesterol-free or cholesterol-enriched diets containing partially hydrogenated soybean oil with different levels of trans-fatty acids or unhydrogenated soybean oil at the 10% level. The linoleic acid content of hydrogenated fat diets was adjusted to 3.6% of the total energy. Hydrogenated fat diets contained 29% and 41% trans-acids, mainly as t-18:1. Trans-fats exerted no untoward effects on growth parameters, but increased liver weight. Dietary hydrogenated fats influenced neither the concentration nor composition of biliary steroids, irrespective of the presence or absence of cholesterol in the diet. In rats fed a cholesterol-free diet, daily fecal output of neutral and acidic steroids was enhanced by hydrogenated fats and the magnitude of augmentation was proportional to the dietary level of trans-fatty acids. The increased fecal steroid excretion corresponded to an increase in total excreta. Hydrogenated fats also tended to enhance bile acid excretion when feeding a cholesterol-enriched diet. The results suggest that dietary trans-fatty acids, in relation to cis-polyunsaturated fatty acids, provoke demonstrable change in steroid homeodynamics.

Influence of Sesame Lignans on Various Lipid Parameters in Rats

“…A similar but lesser degree of liver enlargement has been observed in rats fed with 10% sesame oil. 15) Since there was no accumulation of lipids, except for a slight increase in phospholipid within the normal range, the overall functions of the liver are expected to have been normal, although studies to confirm this are necesssary .…”

Differential Effects of Geometrical Isomers of Octadecadienoic Acids on Ketogenesis and Lipid Secretion in the Livers from Rats Fed a Cholesterol-Enriched Diet

“…in the feeding trials [5][6][7][8][9], since they appar ently repressed the net influx of cholesterol and triglyceride from liver into the blood stream. Fatty acid compositions of triglyceride, phospholipid and cholesterol ester in perfu sate obtained at 4 h and postperfused livers are summarized in table 4.…”

“…cis.trans/trans.cis-and trans.trans-18:2 acids on ketogenesis and lipid secretion in the perfused liver system was also recipro cal and appeared to depend on the number and position of the /ram-double bond in the molecule [4], These observations emphasized, in the liver of rats fed a diet free of cholesterol, that isomerization of the cw-double bond to /ram-configuration at the specified position in the unsaturated fatty acids is crucial for an altered partition between the pathways of oxi dation and esterification. In this context, rats fed the diets containing /raw-fatty acids as compared to d.v-fatty acids showed a marked reduction in the concentration of hepatic tri glyceride and cholesterol [5][6][7][8][9], There is, how ever, little information whether these re sponses could be duplicated when rats were fed a cholesterol-enriched diet.…”

Effects of Simultaneous Intake of Soybean Protein and Diacylglycerol on Lipid Profiles and Body Fat Accumulation in Rats

“…Liver phospholipids concentrations were assayed by the method of Nagata et al 18) Extraction of fecal total lipids and assay of fecal bile acids. Fecal total lipids were extracted from lyophilized feces 3 times with ethanol at 70 C for 1 h. 19) The contents of fecal bile acids were assayed enzymatically using hydroxysteroid dehydrogenase, as described elsewhere, 20) with minor modifications. The standard used for this assay was cholic acid.…”