Liver cholesterol levels

LeHoux and Grondin (1993) investigated the effects of chitosan on plasma and liver cholesterol levels, liver weight, and 3-hydroxy-3-methylglutaryl coenzyme A reductase in rats fed on a sterol diet (1% cholesterol and 0.2% cholic acid). Chitosan at a level of 5% lowered plasma and liver cholesterol levels by 54% and 64%, respectively. High MW chitosan (>750 kDa) had less hypocholesterolemic potential than that of 70 kDa. 

Lactitol. Lactitol (4-0-/ -D-galactopyranosyl-D-sorbitol), is a synthetic sugar alcohol produced on reduction of lactose, usually using Raney nickel. It can be crystallized as a mono- or di-hydrate. Lactitol is not metabolized by higher animals it is relatively sweet and hence has potential as a non-nutritive sweetener. It is claimed that lactitol reduces the absorption of sucrose, blood and liver cholesterol levels and to be anticariogenic. It has applications in low-calorie foods (jams, marmalade, chocolate, baked goods) it is non-hygroscopic and can be used to coat moisture-sensitive foods, e.g. sweets. 

Based on our knowledge of the facts that (a) lipoproteins are carriers of cholesterol in the blood stream, (b) they are involved in atherogenesis,(c) pectin when supplemented in diet causes lowering of serum and/or liver cholesterol in man as well as a number of laboratory animals and (d) polyanionic glycosaminoglycans interact with lipoproteins, it was of interest to us to investigate the interaction of polyanionic pectin with lipoproteins in order to explain the biochemical basis by which pectin may cause lowering of serum/liver cholesterol levels. 

The significance of the observed interaction between pectin and LDL, and further biochemical elucidation of this interaction, has direct relevance to the etiology and/or cure of atherosclerosis. The role of dietary pectin in lowering of serum and liver cholesterol levels is well established. However, the biochemical basis by which dietary pectin, which is composed of... 

Pectin with 62% D.E. largely counteracted the increase in liver cholesterol levels brought about by dietary cholesterol. Low ester pectin (30% D.E.), polygalacturonic acid (PGA), and 50% esterified PGA were all without effect. Conflicting reports on the efficacy of pectin as a hypocholesterolemic agent may be due to variations in these parameters. For example, citrus pectin was found to be more effective than tomato pectin in lowering serum and hepatic cholesterol levels of rats (79). 

The properties of 7a-hydroxylase from pigeon liver microsomes305 and from rat liver306,307 have been further described, and new assay methods are available.308,309 Free cholesterol, rather than a cholesteryl ester, was the preferred substrate for the enzyme from rat liver microsomes,310 and the substrate pool for the hydroxylase was about one third of the total amount of cholesterol present in the microsomal preparation.309 Cholesterol 7a-hydroxylase activity is more sensitive to thyroid function than are the activities of the enzymes responsible for cholesterol synthesis,311 and (22f )-22-aminocholesterol, although having no effect on serum or liver cholesterol levels in rats, drastically reduced 7a-hydroxylase activity.312... 

A number of substituted benzenesulfonic acid esters and p-chlorophenoxy-isobutyric acid esters produced hypolipidemic activity.35 Among a series of p-alkoxybenzoic acids, enhanced hypotriglyceridemic and hypocholesterol-emic activity was observed with oximino- (14) and chloro- (15) substituents.98 Hypocholesterolemia was observed after the administration of 16 to rats.97 Tetronic 701, a polymeric surfactant, also lowered serum cholesterol the tetrabenzoate of Tetronic 701 is of particular interest, since it produced comparatively less growth depression.98 Two linoleamide derivatives, (-)N-fa-phenyl-B-(p-tolyl)ethylllinoleamide (PTLA) and N-(a-methyl-benzoyl)linoleamide, suppressed serum and liver cholesterol levels in rats and inhibited cholesterol absorption b interfering with the hydrolysis of cholesteryl esters in the intestine.99 101... 

Cholestyramine and colestipol are bile acid sequestranls that enhance cholesterol loss into the feces, thereby stimulating new bile salt synthesis, which lowers liver cholesterol levels and consequently plasma LDL levels. Their adverse effects are also listed. 

FH represents only about 2% of HPCs. All others, although likely to involve some genetic factors, have a major dietary component. It is now understood that any increased liver cholesterol levels will decrease LDL receptor synthesis by a biofeedback mechanism. Therefore, any reason for elevated cholesterol levels such as increased absorption or decreased bile acid synthesis can lead to primary HPC not of the familial type. In addition, reduced receptor activity may complicate the picture, either because there are fewer of them or they function less efficiently (e.g., lowered LDL affinity). Drug therapy is potentially useful in such patients. 

Recent clinical studies have shown that the plant C. longa L. significantly reduces blood lipid (I). As shown in Table III, curcumin can also significantly reduce blood and liver cholesterol levels. Therefore, these studies suggest that curcumin may be the active ingredient responsible for the lipid-lowering effects of the plant C. loiiga L... 

The Effect of Pectin and Fat on Serum and Liver Cholesterol Levels and the Recovery of Radioactive Cholesterol (% Intake) in the Liver of Rats 48-Hour and 72-Hour After Feeding Cholesterol-4-14c... 

Similar data have been reported for liver cholesterol levels in rats (7). Germfree and conventional rats fed a cholesterol-free diet had similar liver cholesterol levels however, as the amount of cholesterol in the diet was increased, the liver cholesterol levels of the germfree rats rose three times higher than did those of the comparable conventional rats. In these rats, the serum cholesterol levels did not change with microbiological status or dietary cholesterol. 

Sechi, A. M., Borgatti, A. R. and Lenaz, G. Variation in blood and liver cholesterol levels in lysine-deficient rats effects of lysine and orotic acid. Boll. Soc. Ital. Biol. Sper., 44, 2183-2185 (1968) (Ital.)... 

The effect of vitamin A deficiency on the performance of several biosynthetic pathways has also been investigated. Vitamin A deficiency does not affect cholesterol, fatty acid, or protein synthesis, but it has been claimed to interfere with DNA synthesis. This is probably an indirect effect resulting from the general retardation of growth that accompanies vitamin A deficiency. Plasma and liver cholesterol levels are not changed in vitamin A deficiency however, cholesterol intake reduces the vitamin A stored in rat liver. 

Young rats fed extmded oats, barley or wheat had lower total semm and liver cholesterol levels than did rats fed a control diet or feeds containing unextmded grains (Wang and Klopfenstein, 1993). Soluble fiber increased due to extmsion in all feed samples, and soluble p-glucans increased slightly in extruded oats and barley. Aqueous suspensions of... 

Peterson, D. W., C. W. Nichols jr., and E. A. Shneour Some relationship among dietary sterols, plasma and liver cholesterol levels, and atherosclerosis in chicks. J. Nutr. 47,57 (1952). 

An effect of niacin in decreasing the blood cholesterol level was observed by Altschul (1956), Altschul et al. (1955), and Altschul and Hoffer (1958), in rabbits. Schon (1958) found a similar result in the liver cholesterol levels of the rat. 

Studies have shown that orally fed alginic acid and sodium alginate depress plasma and/ or liver cholesterol levels in rats only algin with a high DP is active. Hypocholester-olemic activity was attributed to the inhibition of cholesterol absorption from the gut. 

Guar gum has been reported to lower the serum and liver cholesterol levels in chickens... 

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