| For medical practitioners and the general public - Cholesterol Journal Article Catalog. |
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| Effectiveness of dietary advice given by community dietitians to men with elevated blood cholesterol in a clinical setting: a pilot study Drummond, S., T. Kirk, et al. (2003), J Hum Nutr Diet 16(2): 81-3. Abstract: OBJECTIVE: To compare the effect of two types of dietary advice given by community dietitians on subsequent dietary intake in Scottish men, over 8 weeks. DESIGN: A parallel design intervention study was employed. Twenty-five men with elevated blood cholesterol levels were randomly assigned to Group 1 (advice to reduce dietary fat only) or Group 2 (advice to reduce dietary fat and sugar). RESULTS: Neither group significantly reduced fat intakes, yet both groups self-rated their fat intake as being lower at the end than at the start of the study. Group 2 reduced per cent energy from sugar and increased per cent energy from starch without significantly changing per cent energy from total carbohydrate. No significant change in blood cholesterol levels were observed. CONCLUSIONS: Advice to reduce dietary fat was not effective in this group of subjects. Advice to reduce both fat and sugar resulted in a decrease in sugar intake only. Both groups wrongly rated their fat intake to be lower at the end of the study. This may be a barrier to further dietary advice. |
| Effectiveness of education-screening on cholesterol levels of students Heyden, S., K. A. Schneider, et al. (1991), Ann Nutr Metab 35(2): 71-6. Abstract: Increases of cholesterol levels from the age of 16 years have been demonstrated in community-based studies. Cholesterol education to students aged 15-17 years in 5 high schools was presented prior to cholesterol screening with the Reflotron. First screening took place in March 1987. An identical program was repeated 11 months later, again followed by screening in March 1988. Of the 5 schools, 2 were assigned to involve teachers. There was a significant cholesterol reduction in these 2 schools, i.e., -17 and -19 mg/dl (p less than 0.05). The effectiveness of the physicians' education and the compliance of the students with the teachers' recommendations certainly must have been enhanced by a different family environment with a higher socioeconomic stratum prevailing in these 2 high schools. However, these factors did not influence the baseline in all 5 schools. In the 3 remaining schools no increases in cholesterol levels expected for this age were observed. |
| Effectiveness of intentional lateralization of the tympanic membrane to promote drainage of a large intracranial cholesterol cyst Horinouchi, K., S. Komune, et al. (2003), Nippon Jibiinkoka Gakkai Kaiho 106(12): 1135-8. Abstract: A 57-year-old male presented with headache and cerebellar symptoms. A magnetic resonance image demonstrated that the brain stem and the cerebellum were compressed by a large intracranial cholesterol cyst. Abundant drainage from the cyst into the tympanic cavity following the intentional lateralization of the tympanic membrane was very successful in aerating the cyst via the tympanic cavity, resulting in the eradication of the cyst. Our new method is recommended as a curative treatment for large intracranial cholesterol cysts because of its limited surgical stress and high radicality. |
| Effectiveness of low-dose lovastatin in lowering serum cholesterol. Experience with 56 patients Bates, M. C., S. G. Warren, et al. (1990), Arch Intern Med 150(9): 1947-50. Abstract: This study reviews the progress of 56 consecutive patients with type IIa and IIb hyperlipoproteinemia following treatment with lovastatin. Lovastatin, a potent inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, has been shown to have a cholesterol-lowering effect in doses ranging from 10 to 80 mg/d. Thus far, however, no large study has been performed to show the effectiveness of low-dose lovastatin (20 mg/d) for more than a 6-week duration. Fifty-six patients with known coronary artery disease were prospectively studied, with fasting lipid values being measured at baseline and after 6, 12, 18, and 24 weeks of 20-mg/d lovastatin therapy given as a single evening dose. The total cholesterol level fell 26% from a mean baseline of 8.12 mmol/L (314 mg/dL) and triglyceride levels fell by 12% from a mean baseline of 2.46 mmol/L. The high-density lipoprotein levels increased 7.6%. One patient with known preexisting liver disease was withdrawn from the study owing to an asymptomatic significant rise in liver function test results; one subject complaining of proximal muscle weakness was also withdrawn. The maximal decrease in total cholesterol level occurred within 6 weeks of initiation of therapy. We conclude that low-dose (20-mg/d) lovastatin was effective in lowering serum cholesterol levels in patients with primary type IIa or IIb hyperlipoproteinemia with minimal short-term side effects. Further studies are needed to establish the long-term safety and effectiveness of this drug. |
| Effectiveness of probucol in reducing plasma low-density lipoprotein cholesterol oxidation in hypercholesterolemia Masana, L., M. T. Bargallo, et al. (1991), Am J Cardiol 68(9): 863-7. Abstract: Oxidized low-density lipoprotein (LDL) interacts with macrophages to induce intracellular cholesterol ester accumulation and foam cell formation. Probucol is a lipid-lowering drug with a well-known antioxidant action. The thiobarbituric acid (TBA)-reacting substances were measured as an index of plasma and LDL lipid peroxidation in a group of hypercholesterolemic patients compared with a normolipidemic control group. The effect of probucol treatment on plasma and LDL lipid peroxidation in the hypercholesterolemic group was also evaluated. Twenty-five patients (10 men and 15 women) with total cholesterol levels greater than 6.5 mmol/liter were given probucol for 24 weeks. Lipid and apoprotein measurements were obtained at 0, 12 and 24 weeks. TBA-reacting substances were also measured in plasma and the LDL fraction. Twenty-five normolipidemic subjects matched for sex, age and body mass index underwent complete blood analysis for purposes of comparison at week 0. Plasma, LDL and high-density lipoprotein cholesterol, and plasma apoproteins A-I and B significantly decreased after 12 and 24 weeks of probucol treatment. Hypercholesterolemic subjects (men and women) had significantly higher TBA-reacting substances in plasma and LDL than control subjects had (p less than 0.05). The amount of TBA-reacting substances in plasma and LDL showed a very significant decrease after probucol treatment (40 and 44%, respectively, after 24 weeks; p less than 0.05). This reduction was not related to age, sex or body mass index, and was greater than the decrease in lipids. These results support a potential role for probucol as a coadjuvant drug in any lipid-lowering antiatherogenic therapy. |
| Effectiveness of resistant starch, compared to guar gum, in depressing plasma cholesterol and enhancing fecal steroid excretion Levrat, M. A., C. Moundras, et al. (1996), Lipids 31(10): 1069-75. Abstract: Amylase-resistant starch (RS) represents a substrate that can be administered in substantial amounts in the diet, in contrast to gel-forming polysaccharides, such as guar gum (GG). The aim of this work was thus to compare the effects of GG and RS on cholesterol metabolism in rats adapted to 0.4% cholesterol diets, using dietary GG or RS levels (8 or 20%, respectively) that led to a similar development of fermentations, as assessed by the degree of enlargement of the cecum. The RS diet elicited a marked rise in the cecal pool of short-chain fatty acids, especially acetic and butyric acid, whereas the GG diet favored high-propionic acid fermentations. Both polysaccharides markedly altered the cholesterol excretion, from 50% of ingested cholesterol in controls, up to about 70% in rats adapted to the RS or GG diets. With these diets, the fecal excretion of bile acids was enhanced (67 and 144% with the RS and GG diets, respectively). RS and GG diets were effective in lowering plasma cholesterol (about -40%) and triglycerides (-36%). There was practically no effect of the diets on cholesterol in d > 1.040 lipoproteins (high density lipoproteins), whereas RS (and to a larger extent, GG) were very effective to depress cholesterol in d < 1.040 lipoproteins (especially in triglyceride-rich lipoproteins). Fermentable polysaccharides counteracted the accumulation of cholesterol in the liver, especially cholesterol esters. In parallel, liver acyl CoA:cholesterol acyltransferase was depressed in rats fed the RS or GG diets, whereas only the GG diet counteracted the downregulation of 3-hydroxy-3-methylglutaryl-CoA by cholesterol. These data suggest that RS may be practically as effective as a gel-forming gum, such as GG, on steroid excretion and on cholesterol metabolism. |
| Effectiveness of statin titration on low-density lipoprotein cholesterol goal attainment in patients at high risk of atherogenic events Foley, K. A., R. J. Simpson, Jr., et al. (2003), Am J Cardiol 92(1): 79-81. |
| Effectiveness of statin titration on low-density lipoprotein cholesterol goal attainment in patients at high risk of atherogenic events Martin, R. L. (2004), Am J Cardiol 93(4): 525. |
| Effectiveness of the electronic medical record in cholesterol management in patients with coronary artery disease (Virtual Lipid Clinic) Kinn, J. W., M. F. O'Toole, et al. (2001), Am J Cardiol 88(2): 163-5, A5. Abstract: This study demonstrates that the Virtual Lipid Clinic, an electronic medical record with computer-assisted cholesterol management, is associated with improved lipid management in patients with coronary artery disease. In comparison to traditional documentation methods with "pen and paper" charts, outpatient visits utilizing the electronic medical record were associated with a twofold increase in low-density lipoprotein (LDL) documentation, a threefold increase in achieving LDL goal, and a 30% increase in the use of lipid-lowering drugs. |
| Effects of 1,2-diacylglycerol and cholesterol on the hydrolysis activity of phospholipase D in egg-yolk phosphatidylcholine bilayers Yamamoto, I., T. Mazumi, et al. (1993), Biochim Biophys Acta 1145(2): 293-7. Abstract: Effects of cholesterol (Chol) and 1,2-diacylglycerol (DAG) on the hydrolysis activity of phospholipase D (from Streptomyces chromofuscus) were studied in small unilamellar vesicles (SUV) of egg-yolk phosphatidylcholine (PC). 1,2-Diacylglycerol used here is derived from PC. Choline produced in the reaction was monitored by using a choline oxidase-oxygen electrode. Addition of 18.3 mol% Chol into SUV (2 mM PC) led to a small increase in the reaction rate. On the other hand, 18.3 mol% DAG in SUV brought about a 5-6-fold rate of choline production. The apparent maximum velocity, Vmax(app), increased by addition of DAG and Chol in SUV. In PC/Chol-SUV, the effect of increase in Vmax(app) was largely compensated by the increase in the apparent Michaelis constant, Km (app). The Chol and DAG molecules did not have significant effects on the kinetic parameters, when PC was solubilized in the micelles of heptaethylene glycol dodecyl ether. The effects of Chol and DAG are, therefore, not due to specific ones on the enzyme itself, but rather upon the bilayer-organization of the substrate. We discuss the activation of phospholipase D in terms of the influences of DAG and Chol on the structure of hydrophilic region and fluidity of the bilayers. |
| Effects of 2 low-fat stanol ester-containing margarines on serum cholesterol concentrations as part of a low-fat diet in hypercholesterolemic subjects Hallikainen, M. A. and M. I. Uusitupa (1999), Am J Clin Nutr 69(3): 403-10. Abstract: BACKGROUND: Full-fat sitostanol ester-containing margarine reduces serum total and LDL cholesterol, but the effect of plant stanol ester-containing margarine as part of a low-fat, low-cholesterol diet has not been studied. OBJECTIVE: We investigated the cholesterol-lowering effects of 2 novel, low-fat stanol ester-containing margarines as part of a low-fat diet recommended for hypercholesterolemic subjects. DESIGN: In a parallel, double-blind study, 55 hypercholesterolemic subjects were randomly assigned after a 4-wk high-fat diet (baseline) to 3 low-fat margarine groups: wood stanol ester-containing margarine (WSEM), vegetable oil stanol ester-containing margarine (VOSEM), and control margarine (no stanol esters). The groups consumed the margarines for 8 wk as part of a diet resembling that of the National Cholesterol Education Program's Step II diet. The daily mean total stanol intake was 2.31 and 2.16 g in the WSEM and VOSEM groups, respectively. RESULTS: During the experimental period, the reduction in serum total cholesterol was 10.6% (P < 0.001) and 8.1% (P < 0.05) greater and in LDL cholesterol was 13.7% (P < 0.01) and 8.6% (P = 0.072) greater in the WSEM and VOSEM groups, respectively, than in the control group. Serum campesterol concentrations decreased 34.5% and 41.3% (P < 0.001) in the WSEM and VOSEM groups, respectively. Serum HDL cholesterol, sitostanol, campestanol, beta-carotene, and fat-soluble vitamin concentrations did not change significantly from baseline. CONCLUSIONS: We conclude that the low-fat, plant stanol ester-containing margarines are effective cholesterol-lowering products in hypercholesterolemic subjects when used as part of a low-fat, low-cholesterol diet. They offer an additional, clinically significant reduction in serum cholesterol concentrations to that obtained with a low-fat diet alone. |
| Effects of 2-(substituted-sulfanyl)-3,5-dihydro-imidazole-4-one and 2-(substituted-sulfanyl)-1H-imidazole-4,5-dione derivatives on serum HDL-cholesterol Elokdah, H., T. Sulkowski, et al. (2000), Bioorg Med Chem Lett 10(16): 1791-4. Abstract: A series of 2-substituted sulfanyl-3,5-dihydro-imidazole-4-ones and 2-substituted sulfanyl-1H-imidazole-4,5-diones was prepared and shown to increase high density lipoprotein cholesterol over other lipid fractions. Compound 1f showed efficacy in additional animal models. The major metabolite of 1f was isolated and its synthesis is reported. The effects of the metabolite on the lipid profile in rats were investigated. |
| Effects of 2164U90 on ileal bile acid absorption and serum cholesterol in rats and mice Lewis, M. C., L. E. Brieaddy, et al. (1995), J Lipid Res 36(5): 1098-105. Abstract: 2164U90, (3R,5R)-trans-3-butyl-3-ethyl-2,3,4,5-tetrahydro-5-phenyl-1,4- benzothiazepine 1,1-dioxide, was found to be a potent inhibitor of the ileal bile acid active transport system. In vitro, 2164U90 decreased uptake and active transport of taurocholic acid by rat everted ileal sacs with IC50s of 4.0 microM and 1.5 microM, respectively. In vivo, 2164U90 produced dose-dependent increases in 23,25-75Se-labeled homocholic acid taurine (SeHCAT) fecal excretion in rats and mice at doses of 3-30 mg/kg and 1-10 mg/kg, respectively. In rats, 30 mg/kg 2164U90 was equivalent to 500 mg/kg cholestyramine. Two days oral administration of 10 mg/kg 2164U90 to rats decreased the bile concentrations of total bile acids 42%, orally administered 3Htaurocholic acid (3HTC) 82%, and cholesterol 35%. Cholestyramine (500 mg/kg) had effects similar to 2164U90 on total bile acid and orally administered 3HTC concentrations but had no effect on biliary cholesterol. The hypocholesterolemic activity of 2164U90 was determined in cholesterol-cholic acid-fed rats and cholesterol-cholic acid-coconut oil-fed mice. 2164U90 inhibited the dietary-induced increase in dextran sulfate-precipitable lipoprotein cholesterol (VLDL+LDL) at doses comparable to doses needed to increase the fecal excretion of bile acids. These data indicate that 2164U90 decreases bile acid absorption by inhibiting the ileal bile acid active transport system, resulting in hypocholesterolemic activity. |
| Effects of 25-hydroxycholesterol on cholesterol esterification and sterol regulatory element-binding protein processing are dissociable: implications for cholesterol movement to the regulatory pool in the endoplasmic reticulum Du, X., Y. H. Pham, et al. (2004), J Biol Chem 279(45): 47010-6. Abstract: The regulatory pool of cholesterol is located in the endoplasmic reticulum (ER) and is key to how mammalian cells sense and respond to changes in cellular cholesterol levels. The extent of cholesterol esterification by the ER-resident protein, acyl-coenzyme A:cholesterol acyl-transferase (ACAT), has become the standard method for monitoring cholesterol transport to the ER and is assumed to reflect the regulatory pool of ER cholesterol. The oxysterol, 25-hydroxycholesterol (25HC), is thought to trigger intracellular cholesterol transport to the ER. In support of this contention, we confirmed previous reports that 25HC activates cholesterol esterification and is a potent suppressor of the sterol regulatory element-binding protein (SREBP) pathway. Processing of the ER membrane-bound SREBP into a soluble transcription factor is controlled by cholesterol levels in the ER. In this study, we addressed whether or not cholesterol esterification necessarily reflects cholesterol movement to the cholesterol homeostatic machinery in the ER as determined by SREBP processing. We found that three agents that inhibited the ability of 25HC to induce cholesterol esterification (progesterone, nigericin, and monensin) did not have a corresponding effect on 25HC suppression of SREBP processing. Moreover, ACAT inhibition did not alter the sensitivity of SREBP processing to 25HC. Therefore, cholesterol esterification by the ER-resident protein ACAT is dissociable from cholesterol transport to the cholesterol homeostatic machinery in the ER. In light of our results, we question the security of previous work that has inferred cholesterol transport to the ER regulatory pool based solely on cholesterol esterification. |
| Effects of 26-aminocholesterol, 27-hydroxycholesterol, and 25-hydroxycholesterol on proliferation and cholesterol homeostasis in arterial myocytes Corsini, A., D. Verri, et al. (1995), Arterioscler Thromb Vasc Biol 15(3): 420-8. Abstract: The major relation existing between cell growth and cholesterol homeostasis prompted us to investigate the effect of 26-aminocholesterol (26-NH2), 27-hydroxycholesterol (27-OH), and 25-hydroxycholesterol (25-OH) on these cellular events. To test this relation, we incubated human and rat arterial myocytes with the sterols for 72 hours. All the tested compounds (0.5 to 7.5 mumol/L) inhibited rat and human myocyte proliferation and cholesterol biosynthesis in a dose-dependent manner. 26-NH2 was more potent than oxysterols in inhibiting human myocyte proliferation but equieffective in rat cells; 27-OH and 25-OH displayed similar activity in both cell lines. Inhibition of nuclear incorporation of thymidine in rat myocytes is consistent with decreased cell count. The antiproliferative effect of the tested sterols was reversible. The high inhibition (80%) of cholesterol biosynthesis necessary to induce a decrease in myocyte proliferation suggests a causal relation between the cholesterol synthetic pathway and these cellular processes. In addition, all the tested sterols were able to inhibit hydroxymethyl glutaryl-coenzyme A reductase activity in intact myocytes but not in cell-free extracts. The finding that 26-NH2 but not 27-OH or 25-OH does not suppress LDL receptor activity in either human or rat myocytes supports the achievement of selectivity over the coordinately regulated LDL receptor gene. The ability of 26-NH2 to interfere with myocyte proliferation and cholesterol synthesis without affecting the LDL receptor pathway confers at least in vitro a pharmacological interest on the compound in the process of atherogenesis. |
| Effects of 32-oxygenated lanosterol derivatives on 3-hydroxy-3-methylglutaryl coenzyme A reductase activity and cholesterol biosynthesis from 24,25-dihydrolanosterol Sonoda, Y., N. Obi, et al. (1992), Chem Pharm Bull (Tokyo) 40(10): 2796-9. Abstract: The effects of 32-oxygenated lanosterol derivatives on 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity and cholesterol biosynthesis from 24,25-3H24,25-dihydrolanosterol were studied. Among the derivatives, 3 beta-hydroxylanost-7-en-32-oic acid was the most active in depressing HMG-CoA reductase activity (IC50: 0.7 microM) and cholesterol biosynthesis (IC50: 0.4 microM) from 24,25-dihydrolanosterol. |
| Effects of a 2,3-oxidosqualene-lanosterol cyclase inhibitor 2,3:22,23-dioxidosqualene and 24,25-epoxycholesterol on the regulation of cholesterol biosynthesis in human hepatoma cell line HepG2 Dollis, D. and F. Schuber (1994), Biochem Pharmacol 48(1): 49-57. Abstract: N-(1,5,9)-trimethyldecyl-4 alpha,10-dimethyl-8-aza-trans-decal-3 beta-ol (8-azadecalin 1), a high-energy intermediate analogue for the 2,3-oxidosqualene-lanosterol cyclase, was found to be a powerful (IC50 approximately 0.1 microM) inhibitor of cholesterol biosynthesis in human hepatoma HepG2 cells. In analogy with other mammalian cells grown in the presence of cyclase inhibitors, the decrease in C27-sterol formation was accompanied by an accumulation of 2,3-oxidosqualene, 2,3:22, 23-dioxidosqualene, and by the formation of a compound characterized as 24,25-epoxycholesterol, a repressor of HMG-CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase activity. In order to assess the cyclase as a potential pharmacological target for the design of hypocholesterolemic drugs, it is important to test whether inhibitors of this enzyme are able to act synergistically on the biosynthesis of cholesterol, i.e. by decreasing the amount of lanosterol formed and by repressing the regulatory HMG-CoA reductase via the formation of regulatory oxysterols. The accumulation of 24,25-epoxycholesterol in relationship to the decrease of C27-sterol biosynthesis and of HMG-CoA reductase activity showed only a partial correlation: e.g. at 1 = 100 x IC50 only a 50% reduction in enzyme activity could be attained. In contrast, when HepG2 cells were treated with 2,3:22,23-dioxidosqualene or 24,25-epoxycholesterol, excellent correlations were found between the inhibition of C27-sterol biosynthesis and the repression of HMG-CoA reductase activity, which was almost complete at the highest concentrations of these epoxides (10(-5) M). Altogether, our results suggest that treatment of HepG2 cells with a cyclase inhibitor such as 8-azadecalin (1) does not lead to an intracellular accumulation of repressor molecules high enough to fully trigger a regulatory pathway resulting in a complete down-regulation of HMG-CoA reductase. At intermediary concentrations of cyclase inhibitors (IC50), however, a synergistic mode of action of these inhibitors seems plausible. |
| Effects of a competitive inhibitor of hydroxymethylglutaryl coenzyme A reductase on cholesterol gallstone formation in prairie dogs Tazuma, S., S. Hatsushika, et al. (1991), Nippon Shokakibyo Gakkai Zasshi 88(8): 1623. |
| Effects of a diet restricted in saturated fatty acids and cholesterol on the composition of apolipoprotein A-I--containing lipoprotein particles in the fasting and fed states Cheung, M. C., A. H. Lichtenstein, et al. (1994), Am J Clin Nutr 60(6): 911-8. Abstract: To test the hypothesis that diet may exert differential effects on apolipoprotein (apo) A-I--containing high-density-lipoprotein (HDL) particles with (w) and without (w/o) apo A-II Lp(A-I w A-II) and Lp(A-I w/o A-II), the effects of a diet low in saturated fatty acids and cholesterol National Cholesterol Education Panel (NCEP) Step 2 diet on these lipoproteins were determined in eight normolipidemic subjects, aged 53-74 y, in both the fasting and nonfasting states. Compared with a diet high in saturated fatty acid and cholesterol, consumption of an NCEP diet (6 mo) lowered fasting plasma, low-density-lipoprotein, and HDL cholesterol, and nonfasting plasma cholesterol, triglyceride, and HDL cholesterol (P < 0.05- < 0.005). Phospholipid in fasting and nonfasting Lp(A-I w A-II) and Lp(A-I w/o A-II) was lower during the NCEP diet (P < 0.05-0.001), but reductions in apo A-I or A-II were observed only in Lp(A-I w A-II). In contrast, differences in particle-size profiles were detected in Lp(A-I w/o A-II) but not in Lp(A-I w A-II). These observations provide further evidence that Lp(A-I w A-II) and Lp(A-I w/o A-II) are distinct metabolic entities. |
| Effects of a dietary oxidized fat on cholesterol in plasma and lipoproteins and the susceptibility of low-density lipoproteins to lipid peroxidation in guinea pigs fed diets with different concentrations of vitamins E and C Eder, K., U. Keller, et al. (2004), Int J Vitam Nutr Res 74(1): 11-20. Abstract: To investigate the effect of a dietary oxidized fat on the concentrations of cholesterol in liver, plasma, and lipoproteins and the susceptibility of low-density lipoproteins (LDL) to lipid peroxidation, and to explore the effects of vitamins E and C, male guinea pigs were divided into five groups. Four groups were fed diets with an oxidized fat supplemented with 35 or 175 mg alpha-tocopherol equivalents/kg and 300 or 1000 mg of vitamin C/kg for 29 days. One group, used as a control, was fed the same basal diet with fresh fat with 35 mg alpha-tocopherol equivalents/kg and 300 mg of vitamin C/kg. Guinea pigs fed the oxidized-fat diets, irrespective of dietary vitamin E and C concentrations, had significantly lower concentrations of total cholesterol in the liver and a lower concentration of cholesterol in LDL than the control animals fed the fresh fat. According to the lag time before onset of lipid peroxidation, LDL of guinea pigs fed the oxidized-fat diet with 35 mg alpha-tocopherol equivalents and 300 mg vitamin C/kg were significantly more susceptible to copper-induced lipid peroxidation than those of guinea pigs fed the fresh fat diet. Within the groups fed the oxidized fat diets, increasing the dietary vitamin E concentration from 35 to 175 mg/kg significantly (p < 0.05) and increasing the dietary vitamin C concentration from 300 to 1000 mg/kg in tendency (p < 0.10) reduced the susceptibility of LDL to oxidation. LDL of guinea pigs fed the oxidized fat diets with 175 mg alpha-tocopherol equivalents/kg were even more resistant to oxidation than LDL of guinea pigs fed the fresh diet. In conclusion, the study shows that dietary oxidized fat influences the cholesterol metabolism and the susceptibility of LDL to lipid peroxidation; the latter can be modified by dietary vitamins E and C. |