Cholesterol metabolism, effects

Evans, A.J. Hood, R.L. Oakenfull, D.G. Sidhu, G.S. (1992). Relationship between structure and function of dietary fibre a comparative study of the effects of three galactomannans on cholesterol metabolism in the rat. British Journal of Nutrition, Vol.68, No.l, (July 1992), pp. 217-229, ISSN 0007-1145. 

This assay has been used by some authors to evaluate the in vitro effects of antioxidant extracts on LDL oxidation (Viana and others 1996 Cirico and Omaye 2006 Kedage and others 2007 Vayalil 2002 Garcfa-Alonso and others 2004 Tarwadi and Agte 2005). Oboh and others (2007) confirmed that hot pepper prevents in vitro lipid peroxidation in brain tissues. Indeed, Bub and others (2000) demonstrated that a moderate intervention with vegetable products rich in carotenoids reduces lipid peroxidation in men. Nicolle and others (2003) evaluated the effect of carrot intake on antioxidant status in cholesterol-fed rats. Later on, they showed that lettuce consumption improves cholesterol metabolism and antioxidant status in rats (Nicole and others 2004). 

Bobek P, Ozdin L and Hromadova M. 1998. The effect of dried tomato, grape and apple pomace on the cholesterol metabolism and antioxidative enzymatic system in rats with hypercholesterolemia. Nahrung 42(5) 317— 320. 

Nicolle C, Cardinault N, Aprikian O, Busserolles J, Grolier P, Rock E, Demigne C, Mazur A, Scalbert A, Amouroux P and Remesy C. 2003. Effect of carrot intake on cholesterol metabolism and on antioxidant status in cholesterol-fed rat. Eur J Nutr 42(5) 254-261. 

Leng-Peschlow, E. (1993). Effect of fibre on key enzymes of cholesterol synthesis and degradation In "Workshop on the Mechanisms of Action of Dietary Fibre on Lipid and Cholesterol Metabolism." Published by the Commission of the European Communities, Luxembourg, pp. 99-101. 

Cholesterol metabolism. Hydrogenated oil, administered orally to hamsters at a dose of 20% of diet for 4 weeks, induced hypercholesterolemia. Oil feeding had no effect on cholesterol synthesis but markedly inhibited cholesterol esterification in both the liver and the intestine. The diet-induced hypercholesterolemia was strongly correlated with an increase in acyl-CoA/cholesterol acyltransferase activity. The hypercholesterolemia increased aortic uptake of cholesterol and hence acyl-CoA/cholesterol acyltransferase activity " Coconut fat, administered orally to rabbits with partial ileal bypass, produced a significant increase of serum total cholesterol and phospholipids concentrations. The effect on semm lipids of the type of fat was similar in control and partial ileal bypass rabbits A Coconut—a main source of energy for two... 

CN109 Jackson, B., A. N. Gee, M. Martinez-Cayuela, and K. E. Suckling. TTie effects of feeding a saturated fat-rich diet on enzymes of cholesterol metabolism CN120 in the liver, intestine and aorta of the hamster. Biochim Biophys Acta 1990 ... 

Lipid metabolism effects. Grains, in the ration of rats at a dose of 68 g/animal daily for 3 months, were active vs rats fed tapioca. Total serum cholesterol and triglycerides were higher than animals fed tapioca. Glucose-6-phosphate levels were lower, and triglyceride lipase and lipoprotein lipase were increased over levels found in the tapioca group k Seed oil, in the ration of rats at a concentration of 10% of the diet, was active. Liver triglycerides were lower in rats fed rice brain oil than those fed peanut... 

Hypolipidemic activity. Seed hull, administered to mice at a dose of 2.5% of diet for 18 weeks, was inactive " . The husk, administered orally to male Hartley guinea pigs at doses of 7.5 or 10 g/100 g of Plantago ovata for 4 weeks, exerted a hypolipidemic effect by affecting bile acid absorption and altering hepatic cholesterol metabolism Insulin release inhibition. Seed administered orally to 18 patients with noninsulin-dependent diabetes at a dose of 13.6 g/day lowered insulin levels by 17% . 

Segawa, K., T. Kataoka, and Y. Fukuo. Cholesterol-lowering effects of psyllium seed associated with urea metabolism. Biol Pharm Bull 1998 21(2) 184-187. 

PO025 Me Call, M. R., T. Mehta, C. W. Leathers, and D. M. Foster. Psyllium husk I. Effect on plasma lipoprotein, cholesterol metabolism, and artherosclerosis in African green monkeys. Amer J Clin Nutr 1992 56(2) 376-384. 

MartineZ Lirola, M. J., M. R. Gonzalez-Tejero, andj. Molero-Mesa. Ethnobo-tanical resources in the province of Almeria, Spain Campos de Nijar. Econ Bot 1996 50(1) 40-56. Arjmandi, B. H., E. Sohn, S. Juma, S. R. Murthy, and B. P. Daggy. Native and partially hydrolyzed psyllium has comparable effects on cholesterol metabolism in rats. J Nutr 1997 127(3) 463-469. 

Mechanism of Action An antihyperlipidemicthat interferes with cholesterol biosynthesis by inhibiting the conversion of the enzyme hydroxymethylglutaryl-CoA (HMG-CoA) to mevalonate, a precursor to cholesterol. Therapeutic Effect Decreases LDL cholesterol, VLDL, and plasma triglyceride levels, increases HDL concentration. Pharmacokinetics Protein binding 88%. Minimal hepatic metabolism. Primarily eliminated in the feces. Half-life 19 hr (increased in patients with severe renal dysfunction). 

Enconragingly, there is increasing, robust scientific evidence that atherosclerosis can be arrested and even decreased by pharmacologic approaches. However, the evaln-ation of drug therapy for this condition is complicated by the fact that the regulation of cholesterol metabolism alone does not necessarily have a beneficial effect on atherosclerosis. 

Glueck, C. J., Tsang, R., Balistreri, W. and Fallat, R. 1972. Plasma and dietary cholesterol in infancy Effects of early low or moderate dietary cholesterol intake on subsequent response to increased dietary cholesterol. Metabolism 21, 1181-1192. 

Metabolic effects of tumor necrosis factor alfa include a reduction in cholesterol and high-density lipoproteins, increases in triglycerides and very low-density lipoproteins, and hyperglycemia. 

The HMG-CoA reductase inhibitors therefore improve several aspects of the plasma lipid profile. These agents may produce several favorable effects that are independent of their ability to affect plasma lipid levels.9,96 It appears that certain by-products of cholesterol metabolism act directly or influence the production of other chemical signals that adversely affect cellular function in various tissues.9 Increased production of these by-products could therefore influence a variety of pathological conditions. By controlling the production of these by-products, statins may produce a wide range of beneficial effects in addition to their ability to improve plasma lipids. 

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