| For medical practitioners and the general public - Cholesterol Journal Article Catalog. |
| First Page | Previous Page | Next Page | Last Page |
| Effect of repeated exercise bouts on high density lipoprotein-cholesterol and its subfractions HDL2-C and HDL3-C Angelopoulos, T. J., R. J. Robertson, et al. (1993), Int J Sports Med 14(4): 196-201. Abstract: Nine sedentary men (mean age, 22.8 yrs) were studied during and after treadmill exercise at 65% VO2max to determine the number of repeated exercise bouts required to bring about a sustained elevation in HDL-cholesterol and its subfraction HDL2-C and HDL3-C. A Latin square counterbalanced design was used. Thirty minute exercise sessions were undertaken in the following patterns: (1) single bout, (2) two bouts on alternate days, and (3) three bouts on alternate days. The exercise bouts in patterns 2 and 3 were separated by 48 h. Patterns 1, 2 and 3 were conducted 7 days apart. Blood samples were obtained prior to each pattern and at 5 min, 24 and 48 h after the last session within each pattern. There were no significant differences in triglycerides and total cholesterol between the selected blood sampling points for all patterns. Total HDL-C remained higher (p < 0.05) than the pre-exercise level 5 min pattern 1: 39.0 vs 41.2 mg.dl-1, pattern 2: 37.1 vs 39.2 mg.dl-1, pattern 3: 38.8 vs 42.7 mg.dl-1 and 24 h pattern 1: 39.0 vs 39.4 mg.dl-1, pattern 2: 37.1 vs 39.1 mg.dl-1, pattern 3: 38.8 vs 42.6 mg.dl-1 post-exercise. Total HDL-C declined to pre-exercise values 48 h post-exercise in all patterns. HDL2-C was lower (p < 0.05) than pre-exercise 48 h for all exercise patterns. For all patterns, HDL3-C levels were higher (p < 0.05) at the 5 min and 48 h post-exercise time points than at the pre-exercise.(ABSTRACT TRUNCATED AT 250 WORDS) |
| Effect of response to a low-fat diet among adolescent males on their adult blood cholesterol levels Ellison, R. C., L. L. Moore, et al. (1997), Prev Med 26(5 Pt 1): 686-93. Abstract: BACKGROUND: While primary prevention of adult cardiovascular diseases should begin early, there are problems in identifying children at increased risk of future disease. METHODS: We did a follow-up study in 1991-1992 of 100 male former students at a boarding high school who had blood cholesterol measured in 1970-1971 both prior to and following a school-wide, reduced-fat dietary intervention. We compared adult cholesterol levels of the 50 subjects whose cholesterol decreased > or = 16.5% (the median decrease) following the 1970-1971 intervention (Diet-Sensitive) with the 50 whose response was < 16.5% (Non-Diet-Sensitive). RESULTS: Blood cholesterol of adults who were Diet-Sensitive in 1970-1971 was 4.2 mg/dl lower than their baseline values in adolescence, while adults classified as Non-Diet-Sensitive as adolescents showed a 15.9 mg/ dl increase in cholesterol over 21 years. Adjusting for baseline adolescent values, Non-Diet-Sensitive subjects were 4.8 (95% CI 1.4, 15.9) times as likely as Diet-Sensitive subjects to have adult cholesterol > or = 200 mg/ dl. Also, Diet-Sensitive adults on a low-fat diet had adult blood cholesterol levels > 20 mg/dl lower than Non-Diet-Sensitive adults on a similar diet (180.1 vs 202.1 mg/dl, respectively). CONCLUSIONS: Degree of response to a low-fat, low-cholesterol diet during adolescence may identify male subjects who will have differing patterns of cholesterol change over time. |
| Effect of rosuvastatin on low-density lipoprotein cholesterol in patients with hypercholesterolemia Olsson, A. G., J. Pears, et al. (2001), Am J Cardiol 88(5): 504-8. Abstract: Rosuvastatin is a new, synthetic, orally active statin, with marked low-density lipoprotein (LDL) cholesterol-lowering activity. We conducted 2 dose-ranging studies. In the first study, after a 6-week dietary run-in, 142 moderately hypercholesterolemic patients were randomized equally to receive double-blind placebo or rosuvastatin 1, 2.5, 5, 10, 20, or 40 mg or open-label atorvastatin 10 or 80 mg once daily for 6 weeks; in the second study, conducted to extend the rosuvastatin dose range, 64 patients were randomized to double-blind, once-daily placebo or rosuvastatin 40 or 80 mg (1:1:2 ratio) for 6 weeks. Data from both studies were combined for analysis of lipid effects. No statistical comparison of atorvastatin arms with placebo or rosuvastatin was performed. Rosuvastatin was associated with highly significant dose-dependent reductions in LDL cholesterol compared with placebo (p <0.001); decreases ranged from 34% (1 mg) to 65% (80 mg). Linear regression analysis indicated an additional 4.5% LDL cholesterol reduction for each doubling of the rosuvastatin dose. Across the dose range, approximately 90% of LDL cholesterol reduction occurred within the first 2 weeks of treatment. Significant, dose-dependent reductions in total cholesterol and apolipoprotein B with rosuvastatin were also observed (p <0.001). High-density lipoprotein cholesterol increases and triglyceride reductions were consistently observed and statistically significant at some dose levels. All lipid ratios were significantly reduced at all rosuvastatin dose levels (p <0.001). Adverse events were similar across placebo and active treatments. No significant increases in alanine aminotransferase or creatine kinase were seen in any patient. Over 6 weeks, rosuvastatin produced large, rapid, dose-dependent LDL cholesterol reductions and was well tolerated in hypercholesterolemic patients. |
| Effect of rye bran on excretion of bile acids, cholesterol, nitrogen, and fat in human subjects with ileostomies Zhang, J. X., E. Lundin, et al. (1994), Am J Clin Nutr 59(2): 389-94. Abstract: The excretion of bile acids, cholesterol, dry matter, nitrogen, fat, and energy in ileostomy effluent, and plasma lipid concentrations were studied in eight subjects with ileostomies. The subjects consumed a wheat bread-based, low-fiber diet (LFD) for 3 wk and a rye bran bread-based, high-fiber diet (HFD) for 3 wk. The ileal excretion of dry matter, nitrogen, fat, and energy was higher during the HFD period. The daily excretion and the percentage of conjugated bile acids were significantly higher and the percentage of free bile acids lower in the ileostomy effluents during the HFD as compared with the LFD period. No significant difference in the excretion of cholesterol, net cholesterol, sterol, or net sterol was noted between the HFD and LFD periods. No significant differences in plasma concentrations of HDL-, LDL-, and total cholesterol, and apolipoprotein A-I and B were observed between the two 3-wk dietary periods. |
| Effect of sample storage on the measurement of lipoproteina, apolipoproteins B and A-IV, total and high density lipoprotein cholesterol and triglycerides Kronenberg, F., E. M. Lobentanz, et al. (1994), J Lipid Res 35(7): 1318-28. Abstract: This study investigated the influence of long-term storage, for periods up to 24 months, and multiple freezing and thawing on the measured values of lipoproteina (Lpa), apolipoproteins B and A-IV, total and high density lipoprotein (HDL) cholesterol and triglycerides using plasma samples stored at -80 degrees C, -20 degrees C, and 4 degrees C. Samples stored at -80 degrees C or -20 degrees C showed significant changes in Lpa after 24 months, with a mean decrease of 7% and 13%, respectively (P < 0.01). The major part of the decrease occurred during the first freezing and thawing. In contrast, apolipoproteins B and A-IV decreased continuously over time (P < 0.05). The increase in plasma concentrations of total and HDL cholesterol and triglycerides was small but significant because of its uniformity. Multiple freezing and thawing influenced only the measured values of Lpa and apolipoprotein B. Comparison of samples stored at -80 degrees C and -20 degrees C showed no difference in any of the parameters at any time with the exception of Lpa after 18 and 24 months (P < 0.05). After a storage period of 24 months, immunoblotting with detection of apoa was possible from samples under each storage condition. ApoB and apoA-IV were detectable only in samples stored at -20 degrees C or -80 degrees C. These data, when compared to recent studies, suggest a critical role of the assay methodology in the reproducibility of measured Lpa and apolipoprotein plasma concentrations. We therefore recommend the examination of each system for measurement of long-term stored plasma samples. |
| Effect of selenium on serum, hepatic and lipoprotein lipids concentration in rats fed on a high-cholesterol diet Iizuka, Y., E. Sakurai, et al. (2001), Yakugaku Zasshi 121(1): 93-6. Abstract: The effects of Selenium (Se) on lipid metabolism was studied in male Wistar rats which were fed a high-cholesterol diet (HCD) containing 1%(w/w) cholesterol and 0.5%(w/w) cholic acid for 10 weeks. Se was orally administered at daily doses of 0.173 mg/kg in HCD into the test rats for 10 weeks. As compared with control groups, Se/HCD suppressed the amounts of triglyceride (TG), total cholesterol (CH) and free fatty acid in the serum. Se/HCD also decreased the amounts of low-density lipoprotein cholesterol (LDL-C) in the serum. Further-more, Se/HCD inhibited the amount of liver TG and CH. The activity of fatty acid synthetase in the HCD fed group was higher than in the Se/HCD fed group. These results suggest that Se may have recuperative effects for hypercholesterolemia. |
| Effect of serum cholesterol levels on meta-chlorophenylpiperazine-evoked neuroendocrine responses in healthy subjects Terao, T., R. Yoshimura, et al. (1997), Biol Psychiatry 41(9): 974-8. Abstract: This study was undertaken to test the hypothesis that serum cholesterol levels might be associated with serotonergic receptor function. The participants were 10 healthy male subjects. After an overnight fast, the subjects received meta-chlorophenylpiperazine (m-CPP) or identical placebo capsules orally in a randomized, double-blind, cross-over design. Blood was obtained for measurement of prolactin, cortisol, adrenocorticotropic hormone (ACTH), and cholesterol. There were some significantly positive correlations between serum cholesterol levels and hormonal responses to m-CPP administration. These results suggest that serum cholesterol levels may be positively associated with serotonergic receptor function. |
| Effect of serum cholesterol on the mRNA content of amyloid precursor protein in rat livers Kiyosawa, N., K. Ito, et al. (2004), Toxicol Lett 150(2): 157-66. Abstract: Genes that showed mRNA content profiles, which correlated with serum concentrations of total cholesterol (T.CHO), were screened from the microarray data of phenobarbital (PB)- or clofibrate (CLO)-treated rat livers, and the correlation was evaluated based on Spearman's correlation coefficient. Many genes involved in the cholesterol or bile acid metabolism were highly correlated such as UDP-glucuronosyltransferase-21, apolipoprotein A-I and cMOAT. The mRNA content of the amyloid precursor protein (APP) showed the 5th highest correlation among the 8799 probes in the Affymetrix Rat Genome U34 Array. In the livers of rats fed a high-cholesterol (1%) diet for 33 days, serum T.CHO levels increased by 4.6-fold, and the hepatic APP mRNA content also increased by 1.9-fold compared to the control group. These data suggest that the hepatic APP mRNA content was affected by serum T.CHO, and that hepatic APP was involved in cholesterol metabolism in rat livers. |
| Effect of serum lipid concentrations on restenosis after successful de novo percutaneous transluminal coronary angioplasty in patients with total cholesterol 160 to 240 mg/dl and triglycerides < 350 mg/dl Dzavik, V., K. K. Teo, et al. (1995), Am J Cardiol 75(14): 936-8. |
| Effect of serum lipoprotein(a) on estimation of low-density lipoprotein cholesterol by the Friedewald formula Li, K. M., D. E. Wilcken, et al. (1994), Clin Chem 40(4): 571-3. Abstract: The calculation of serum low-density lipoprotein cholesterol (LDL-C) by the Friedewald formula does not account for the cholesterol associated with lipoprotein(a) Lp(a). To quantify the contribution of Lp(a) cholesterol to total serum cholesterol, we measured concentrations of serum Lp(a) by an ELISA and concentrations of other serum lipids and lipoproteins by standard assays in 23 normolipemic women, ages 50-60 years. In measuring serum high-density lipoprotein we found that polyethylene glycol 6000 precipitated > 99.8% of all Lp(a). When serum Lp(a) concentrations were < or = 300 mg/L, 301-600 mg/L, and > 600 mg/L, the uncorrected serum LDL-C was overestimated, respectively, by a mean of 4.1% (n = 7), 8.5% (n = 8), and 21.4% (n = 8). Serum Lp(a) concentrations were positively correlated with percentage overestimation (P < 0.001), but were not correlated with either corrected or uncorrected serum LDL-C. We conclude that the Friedewald formula should be modified to take into account the contribution of Lp(a) cholesterol to total serum cholesterol. |
| Effect of serum lyophilization on the rate constants of enzymatic methods for measuring cholesterol Kroll, M. H. and R. Chesler (1990), Clin Chem 36(3): 534-7. Abstract: We determined the equilibrium absorbances and rate constants for two enzymatic methods, aca (DuPont) and RA-1000 (Technicon), used in determining cholesterol in reconstituted lyophilized serum. The lyophilized materials included two serum pools, three control materials, a College of American Pathologists' survey material, and Standard Reference Material no. 909. We calibrated the reagents with aca standards for cholesterol (DuPont). The difference in the mean concentrations of cholesterol (aca - RA-1000) was -0.09 g/L overall and was not statistically significant by analysis of variance. The mean rate constant for all materials was 0.23 min-1 for the aca and 1.42 min-1 for the RA-1000, significantly different (P less than 0.001). Lyophilization causes lower results for the aca method than for the Ra-1000, because the reaction rate for the aca method is slower and has not reached equilibrium when the final absorbance reading is made. |
| Effect of severe incomplete ischaemia and postischaemic reperfusion on phospholipids and unesterified cholesterol in rabbit spinal cord Halat, G., N. Lukacova, et al. (1990), Physiol Bohemoslov 39(4): 351-60. Abstract: Effect of severe incomplete ischemia, induced by occlusion of the abdominal aorta caudal to the left renal artery for 40 min, and postischemic reperfusion for 6 h, 1 and 4 days on phospholipid composition and unesterified cholesterol concentration was studied in the lumbosacral (L3-S1) spinal cord separated into the gracile fascicle (Fg), dorsal part without Fg (Dp) and ventral part (Vp). Ischemia decreased the inositol phospholipid (PI) concentration in Dp and Vp and this was recovered during reperfusion. Within 6 h following ischemia, ethanolamine (PE) and serine (PS) phospholipid concentrations decreased in Dp and PS also in Vp. During the long reperfusion intervals the concentrations of the two major phospholipids, PE and choline phospholipid (PC) declined in Fg, Dp and Vp. No changes were observed in sphingomyelin (SM). The concentration of unesterified cholesterol (UC) was lower throughout the reperfusion period in Dp and Vp, while the decrease in Fg was delayed. The molar ratio UC/TPL was reduced starting from 24 h of reperfusion. The pattern of changes, which were delayed in the white matter as compared to Dp and Vp (containing the gray matter) indicated severe damage to the membrane structures in the tissue, developed during reoxygenation, that was related to decreased tissue viability. |
| Effect of short-term and long-term alcohol intake on plasma cholesterol in non-alcoholic humans Nakamura, J. (1994), Clin Chim Acta 224(1): 107-9. |
| Effect of short-term ingestion of konjac glucomannan on serum cholesterol in healthy men Arvill, A. and L. Bodin (1995), Am J Clin Nutr 61(3): 585-9. Abstract: The effects of the soluble fiber konjac glucomannan (GM) on serum cholesterol concentrations were investigated in 63 healthy men in a double-blind crossover, placebo-controlled study. After a 2-wk baseline period, the subjects were given 3.9 g GM or placebo daily for 4 wk. After a washout period of 2 wk, crossover took place, followed by another 4 wk of treatment. The subjects were encouraged not to change their ordinary diets or general lifestyle during the investigation. GM fibers reduced total cholesterol (TC) concentrations by 10% (P < 0.0001), low-density-lipoprotein cholesterol (LDL-C) concentrations by 7.2% (P < 0.007), triglycerides by 23% (P < 0.03), and systolic blood pressure by 2.5% (P < 0.02). High-density-lipoprotein cholesterol (HDL-C) and the ratio of LDL-C to HDL-C did not change significantly. No change in diastolic blood pressure or body weight was observed. No adverse effects were observed. The results of this study show that GM is an effective cholesterol-lowering dietary adjunct. |
| Effect of sickle-cell gene expression on plasma cholesterol in a Nigerian population Oforofuo, I. A. and M. O. Adedeji (1994), Clin Biochem 27(6): 505-8. |
| Effect of silymarin on serum cholesterol levels in rats Skottova, N., V. Krecman, et al. (1998), Acta Univ Palacki Olomuc Fac Med 141: 87-9. Abstract: Previously we have shown that perorally administered silymarin, a mixture of flavonolignans extracted from the seeds of Silybum marianum, possesses a hypocholesterolemic effect in rats fed high cholesterol diet enriched with fat. The aim of this paper was to complete the data concerning peroral and parenteral administration of silymarin. The rats fed standard laboratory diet did not respond to peroral administration of silymarin by decrease of serum cholesterol, but the mild increase in HDL cholesterol was found. Parenterally injected silymarin failed to reduce serum cholesterol both in rats fed high cholesterol diet and standard laboratory diet. The results suggest that silymarin could act either due to the fat-mediated improved bioavailability and/or by inhibiting of resorption of dietary cholesterol. |
| Effect of simvastatin (MK-733) on the regulation of cholesterol synthesis in Hep G2 cells Nagata, Y., Y. Hidaka, et al. (1990), Biochem Pharmacol 40(4): 843-50. Abstract: A new antihypercholesterolemic drug, simvastatin (MK-733), which is a prodrug of a potent 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, inhibited cholesterol synthesis from 14Cacetate concentration dependently without inhibiting it from 3Hmevalonate in Hep G2 cells. Therefore, MK-733 is thought to be converted to L-654,969, the active beta-hydroxy acid form of MK-733 in the cells and/or medium. MK-733 inhibited cholesterol ester synthesis, but did not affect phospholipid, free fatty acid and triacylglycerol synthesis. This compound increased HMG-CoA reductase activity concentration dependently and raised the specific binding, internalization and degradation of 125I-labeled low density lipoprotein by Hep G2 cells. Another HMG-CoA reductase inhibitor, pravastatin (CS-514), also behaved like MK-733. However, its potency was far less than that of MK-733. |
| Effect of simvastatin on the synthesis and secretion of lipoproteins in relation to the metabolism of cholesterol in cultured hepatocytes Ribeiro, A., M. Mangeney, et al. (1991), Biochim Biophys Acta 1086(3): 279-86. Abstract: In primary culture of rat hepatocytes, simvastatin, a powerful HMGCoA reductase inhibitor, inhibited acetate incorporation into cellular and secreted cholesterol and cholesteryl-esters, without any significant effect on triacylglycerol synthesis and secretion. When applied to the culture for 24 h at 10(-7) M, a concentration shown to inhibit cholesterol synthesis by 61%, simvastatin increased apolipoprotein BH and BL synthesis and secretion and strongly decreased apolipoprotein AI synthesis and secretion whereas apolipoprotein AIV remained unaffected. The synthesis and secretion of apolipoprotein E was only slightly affected in contrast with other situations where cholesterol synthesis decreased. All of these modifications occurred at a post-transcriptional level, as the corresponding messenger RNAs of the apolipoproteins did not vary. These results suggest that either the drug itself or variations in cholesterol synthesis might be involved in apo B and apo AI synthesis and secretion. |
| Effect of simvastatin on trioleylglycerol hydrolysis and transacylation with cholesterol in serum of outpatients with coronary heart disease Piorunska-Stolzmann, M., A. Piorunska-Mikolajczak, et al. (2003), Drugs Exp Clin Res 29(1): 37-43. Abstract: At present, the most effective drugs in treating hypercholesterolemia and atherosclerosis are the statins, which are potent inhibitors of the rate-limiting enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase. Serum triacylglycerol (TAG) levels associate positively with the risk for coronary heart disease (CHD). Triacylglycerols are mainly hydrolyzed by the enzyme lipase (glycerol ester hydrolase GEH, EC 3.1.1.3) but can also be transformed by transacylation with cholesterol (glycerol ester:cholesterol acyltransferase GECAT, EC 2.3.1.43). We evaluated the effect of a 3-month treatment with simvastatin (10 mg/day) on GEH and GECAT activity in the serum of 26 outpatients with CHD. The activity of both GEH and GECAT was reduced in the CHD group compared with that in the control group: 5.9 +/- 0.9 mU/mg vs. 7.5 +/- 1.8 mU/mg and 11.1 +/- 1.4 mU/mg vs. 19.3 +/- 3.3 mU/mg, respectively (p < or = 0.05). In addition to the well known effect of reducing total cholesterol and low-density lipoprotein cholesterol in patients with CHD, we observed two other results of simvastatin treatment. First, GEH activity increased to values similar to those found in healthy subjects and, simultaneously, GECAT activity decreased. Trioleylglycerol transacylation with cholesterol amounted to 72% and hydrolysis to 28% in the control group and to 65% and 35% in the CHD group, respectively. After simvastatin treatment, transacylation with cholesterol and hydrolysis amounted to 51% and 49%, respectively. In conclusion, by increasing GEH and reducing GECAT, simvastatin seems not only to affect cholesterol synthesis but also to alter triacylglycerol metabolism. Further studies are needed to determine the physiological significance of these changes and their relationship with the development of atherosclerosis. |
| Effect of sirolimus on the cholesterol content of aortic arch in ApoE knockout mice Basso, M. D., P. Nambi, et al. (2003), Transplant Proc 35(8): 3136-8. Abstract: Chronic inflammatory responses involving the immune system have been implicated in the process of atherosclerosis. Sirolimus (Rapamycin, Rapamune), a potent immunosuppressant used to prevent rejection of transplanted kidneys, has also proven effective at inhibiting restenosis in humans when eluted from implanted stents. The aim of this study was to evaluate the effect of sirolimus treatment on the development of atherosclerosis in the aortic arch of apo E-/- mice fed a high-fat (Western) diet. Following 12 weeks of treatment with sirolimus (4 mg/kg/d), the cholesterol content of the arch was reduced by 36% compared to untreated control mice fed the Western diet only. Although the murine model is not comparable to the human situation, the results of this study suggest that sirolimus may exert beneficial effects on atherosclerosis in transplant patients. |