| For medical practitioners and the general public - Cholesterol Journal Article Catalog. |
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| Effects of randomization of partially hydrogenated corn oil on fatty acid and cholesterol absorption, and tissue lipid levels in rats Koga, T., T. Yamato, et al. (1995), Lipids 30(10): 935-40. Abstract: Randomization of partially hydrogenated corn oil containing approximately 45% of trans octadecenoic acid only slightly, but not significantly, increased the lymphatic fatty acid absorption in rats. No effect of randomization was observed on cholesterol absorption. When rats were fed these fats at the 8.8% level (with 1.2% safflower oil) for three weeks, the concentrations of serum cholesterol, and serum and liver phospholipid were significantly higher in randomized fat than in control fat, which was composed of 9% high-oleic safflower oil and 1% palm oil. Liver cholesterol tended to be higher in randomized fat. In contrast, nonrandomized fat was not hyperlipidemic compared to control fat. Although the fatty acid composition of liver phospholipids suggested a possible interference of trans fatty acid with the metabolism of linoleic acid to arachidonic acid, there was no effect of randomization. In the two hydrogenated fat groups, trans octadecenoic acid was incorporated and distributed similarly in adipose tissue triacylglycerol. These observations indicated that randomization of partially hydrogenated fat is not beneficial to various lipid parameters in rats. |
| Effects of recombinant human macrophage colony-stimulating factor on atherosclerotic lesions established in the aorta of high cholesterol-fed rabbits Irie, H., H. Koshiba, et al. (2001), J Biochem (Tokyo) 129(5): 717-24. Abstract: Anti-atherosclerotic effects of human macrophage colony-stimulating factor were investigated using rabbits fed a high cholesterol diet. Rabbits fed a diet containing 2% cholesterol for 59 days developed hyperlipidemia and atheromatous aortic plaques. They were then administered 80 microg/kg/day of either macrophage colony-stimulating factor or human serum albumin, as a control, for the next 12 weeks. Compared with the control group, rabbits treated with macrophage colony-stimulating factor had significantly fewer plaques on the inner surface of the thoracic and abdominal aortae, and half the sectional area of thickened intima in the aortic arch, as well as in the thoracic and abdominal aortae. Macrophage colony-stimulating factor also decreased the cholesterol content of the atherosclerotic lesions. Serobiochemical analyses revealed that macrophage colony-stimulating factor increased the levels of high density lipoprotein-cholesterol significantly, without influencing other lipid parameters such as the level of low density lipoproteins. The effects of macrophage colony-stimulating factor were evident until the fourth week of drug injection, at which time anti-human macrophage colony-stimulating factor antibodies were clearly induced in the serum. These results indicate that exogenously administered macrophage colony-stimulating factor suppresses atherosclerotic lesions induced by a high cholesterol diet by activating lipid metabolism in vivo. |
| Effects of recombinant human macrophage colony-stimulating factor on plasma cholesterol levels Stoudemire, J. B. and M. B. Garnick (1991), Blood 77(4): 750-5. Abstract: Recombinant human macrophage colony-stimulating factor (rhM-CSF) is a hematopoietic growth factor that stimulates the growth, differentiation, proliferation, and activation of cells of the monocyte/macrophage lineage. rhM-CSF was administered to rabbits and nonhuman primates to evaluate effects on cholesterol homeostasis. Decreases in plasma cholesterol concentrations were observed during rhM-CSF administration. The observed mean (+/- SD) decreases over a range of doses in nonhuman primates receiving rhM-CSF by continuous intravenous infusion (CIVI) or intravenous bolus (IVB) injection were approximately 16% +/- 8% and 43% +/- 10%, respectively. Low-density lipoprotein (LDL) cholesterol levels decreased 55% +/- 9% from pretreatment baseline values in the animals receiving rhM-CSF by IVB. Normocholesterolemic New Zealand white rabbits receiving rhM-CSF over a range of doses by CIVI showed a decrease from baseline in total cholesterol of approximately 28% +/- 17%, with LDL cholesterol levels decreasing by approximately 72% +/- 33%, while high-density lipoprotein levels showed variable changes, including increased values. A decrease of 36% +/- 26% in total plasma cholesterol was observed in Watanabe Heritable Hyperlipidemic rabbits receiving rhM-CSF by CIVI for 7 days. This decrease was attributable almost entirely to decreases in LDL cholesterol, which fell approximately 34% +/- 24% from baseline. Although the mechanism of this cholesterol-lowering effect is unknown, these results strongly suggest that rhM-CSF may provide a novel treatment for hypercholesterolemia and may be useful in investigations into the mechanisms of cholesterol homeostasis and atherogenesis. |
| Effects of reduced maternal lipoprotein-cholesterol availability on placental progesterone biosynthesis in the baboon Henson, M. C., S. J. Greene, et al. (1997), Endocrinology 138(4): 1385-91. Abstract: Maternal low density lipoprotein (LDL) is the principal source of cholesterol substrate for progesterone biosynthesis in the primate placental syncytiotrophoblast. The relationship of LDL-cholesterol availability and other potential cholesterol-yielding pathways to placental progesterone production have not, however, been demonstrated in vivo in a nonhuman primate. Therefore, maternal peripheral lipoprotein-cholesterol and progesterone concentrations were determined in blood samples obtained by venipuncture, from day 72 until day 100, from pregnant baboons (Papio sp) that were either untreated (n = 4) or treated (n = 3) with the inhibitor of hepatic lipoprotein production, 4-aminopyrazolo 3-4-dpyrimidine (4-APP, 10 mg/kg BW) on days 98-99 of pregnancy (term = 184 days). Although LDL-cholesterol and progesterone levels remained unchanged in untreated animals, LDL-cholesterol concentrations were 9-fold lower (P < 0.005) in baboons receiving 4-APP than in untreated baboons 2 days following initial administration. Commensurate progesterone levels were 3.5-fold lower (P < 0.03) in 4-APP-treated baboons than in untreated baboons. RT-PCR was used to approximate relative changes in transcription of messengers RNAs (mRNAs) for selected cholesterol-sensitive pathways in placental tissue collected on day 100. Thus, expression of mRNAs for LDL receptor and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase appeared enhanced, whereas acyl-coenzyme A:cholesterol acyl transferase (ACAT) mRNA was diminished in syncytiotrophoblast-enriched cell fractions as a result of 4-APP administration. No relative differences in mRNAs were apparent in whole placental villous tissue, however, as a result of 4-APP treatment. In summary, this experiment demonstrates a significant decline in progesterone production elicited by maternal LDL-cholesterol withdrawal, and attests to the efficacy of 4-APP administration during baboon pregnancy. These results also suggest a commensurate regulation of cholesterol-sensitive pathways in primate syncytiotrophoblast. However, no relative differences were apparent in mRNA levels for LDL receptor, HMG-CoA and ACAT in whole placental villous tissue as a result of LDL-cholesterol withdrawal, which may suggest potential disparities in the mechanisms regulating cholesterol homeostasis in steroidogenically active syncytiotrophoblasts vs. those in proliferative nonendocrine placental constituents. |
| Effects of regular and extended-release gemfibrozil on plasma lipoproteins and apolipoproteins in hypercholesterolemic patients with decreased HDL cholesterol levels Schaefer, E. J., S. Lamon-Fava, et al. (1996), Atherosclerosis 127(1): 113-22. Abstract: We have studied, in a prospective blinded fashion, the effects of regular and extended-release gemfibrozil on plasma lipoprotein and apolipoprotein (apo) levels in hypercholesterolemic subjects with decreased high density lipoprotein (HDL) cholesterol (C) levels. Study participants were men and women 19 to 80 years of age with baseline plasma low density lipoprotein (LDL) C levels > or = 4.5 mmol/l (175 mg/dl), HDL-C levels < or = 1.2 mmol/l (45 mg/dl), and triglyceride levels < or = 3.4 mmol/L (300 mg/dl). All subjects were stabilized on a diet for eight weeks prior to entry into two different protocols. In the first protocol 229 subjects were randomized to placebo or extended-release gemfibrozil (1200 mg/day) for 3 months (placebo trial). In the second protocol 655 subjects were randomized to regular or extended-release gemfibrozil (1200 mg/day) for 6 months (equivalency trial). Changes in lipids and apos were stratified by baseline HDL-C levels (< 0.9 mmol/l, and 0.9-12.2 mmol/l). In both studies, treatment with gemfibrozil, either regular or extended-release, was associated with significant (P < 0.05) decreases in plasma very low density lipoprotein (VLDL) C and triglyceride levels of 42-45% and 33-37%, respectively, in subjects with HDL-C level < 0.9 mmol/l, and of 38-47% and 32-39%, respectively, in patients with HDL-C levels of 0.9-1.2 mmol/l. Modest reductions from baseline in directly measured LDL-C levels were observed in both groups (3-6% and 8-9%, respectively). These reductions were less than those observed for calculated LDL-C (7-10% and 11%, respectively). For apo B, reductions were 11-14% and 16-17% in the two groups. HDL-C, apo A-I, and apo A-II levels increased by 15-16%, 5-6%, and 21-25%, respectively, in patients with HDL-C < 0.9 mmol/l, and by 6-7%, 2-3%, and 19-22%, respectively, in patients with HDL-C of 0.9-1.2 mmol/l. These differences in HDL-C levels reached statistical significance in the equivalency trial (P < 0.0001) and were independent of baseline triglyceride levels. Our data indicate that gemfibrozil, either regular or extended-release, is highly effective in lowering plasma triglyceride levels and increases HDL-C levels by approximately 15% in hypercholesterolemic patients with low HDL-C levels (< 0.9 mmol/l). Moreover, this agent lowers VLDL-C somewhat more than triglyceride, resulting in an underestimation of calculated VLDL-C reductions and in an overestimation of calculated LDL-C reductions. This agent also raises apo A-II levels much more than apo A-I levels. |
| Effects of repeated freeze-thaw cycles on concentrations of cholesterol, micronutrients, and hormones in human plasma and serum Comstock, G. W., A. E. Burke, et al. (2001), Clin Chem 47(1): 139-42. |
| Effects of riboflavin and fatty acid methyl esters on cholesterol oxidation during illumination Hu, P. C. and B. H. Chen (2002), J Agric Food Chem 50(12): 3572-8. Abstract: The effect of riboflavin or fatty acid methyl esters on cholesterol photooxidation was studied. Samples containing cholesterol, either alone or in combination with riboflavin or fatty acid methyl esters, were illuminated at 25 degrees C in an incubator for 28 days. The various cholesterol oxidation products (COPs) and cholesterol were analyzed by gas chromatography-mass spectrometry (GC-MS), and riboflavin was determined by HPLC. Results showed that the presence of riboflavin or fatty acid methyl esters facilitated production of COPs and degradation of cholesterol, and the degradation fits a first-order model. The COPs formed during light storage included 7 alpha-OH, 7 beta-OH, 7-keto, 3,5-cholestadien-7-one, 5,6alpha-EP, and 5,6beta-EP. The addition of riboflavin caused formation of 3,5-cholestadien-7-one through dehydration of 7-keto, whereas in the presence of docosahexaenoic acid methyl ester, the formation of 5,6alpha-EP or 5,6beta-EP was favored. Riboflavin was more effective for generation of COPs than fatty acid methyl esters. |
| Effects of rosuvastatin on nitric oxide-dependent function in aorta and corpus cavernosum of diabetic mice: relationship to cholesterol biosynthesis pathway inhibition and lipid lowering Nangle, M. R., M. A. Cotter, et al. (2003), Diabetes 52(9): 2396-402. Abstract: Elevated plasma lipids contribute to neurovascular dysfunction in diabetes. Statins have lipid-lowering properties and can modulate endothelial nitric oxide (NO) bioavailability. The aim was to assess the impact of these factors on autonomic nitrergic nerve and endothelial function. Thus, the effects of diabetes and treatment with the HMG-CoA reductase inhibitor rosuvastatin (RSV) were examined on corpus cavernosum and aorta from streptozotocin-induced diabetic mice in a 4-week prevention study and a 2-week intervention study, following 4 weeks of untreated diabetes. Cotreatment with mevalonate was used to assess the dependence of RSV's effects on HMG-CoA reductase blockade. Diabetes caused a 25% reduction in NO-mediated endothelium-dependent relaxation to acetylcholine for aorta and cavernosum. Relaxations of cavernosum were in the nondiabetic range following prevention or reversal treatment. The aortic deficit was completely prevented and 60% reversed by RSV. Maximum NO-dependent nonadrenergic, noncholinergic nerve-mediated relaxations of cavernosum were reduced 25-33% by diabetes. RSV treatment prevented 75% and reversed 71% of this diabetic deficit. Cotreatment with mevalonate inhibited the beneficial actions of RSV on aorta and cavernosum. Total plasma cholesterol was unaltered by diabetes or treatment. Thus, RSV corrected defective NO-mediated nerve and vascular function in diabetic mice independent of cholesterol lowering but via effects dependent on cholesterol biosynthesis pathway inhibition. |
| Effects of rosuvastatin versus atorvastatin, simvastatin, and pravastatin on non-high-density lipoprotein cholesterol, apolipoproteins, and lipid ratios in patients with hypercholesterolemia: additional results from the STELLAR trial Jones, P. H., D. B. Hunninghake, et al. (2004), Clin Ther 26(9): 1388-99. Abstract: BACKGROUND: Non-high-density lipoprotein cholesterol (HDL-C), apolipoprotein (apo) B, and lipid and apolipoprotein ratios that include both atherogenic and antiatherogenic lipid components have been found to be strong predictors of coronary heart disease risk. OBJECTIVE: The goal of this study was to examine prospectively the effects of rosuvastatin, atorvastatin, simvastatin, and pravastatin across dose ranges on non-HDL-C, apo B, apo A-I, and total cholesterol (TC):HDL-C, low-density lipoprotein cholesterol (LDL-C):HDL-C, non-HDL-C:HDL-C, and apo B:apo A-I ratios in patients with hypercholesterolemia (LDL-C > or =160 mg/dL and <250 mg/dL and triglycerides <400 mg/dL) in the Statin Therapies for Elevated Lipid Levels compared Across doses to Rosuvastatin (STELLAR) trial. METHODS: In this randomized, Multicenter, parallel-group, open-label trial (4522IL/0065), patients > or =18 years of age received rosuvastatin 10, 20, 40, or 80 mg; atorvastatin 10, 20, 40, or 80 mg; simvastatin 10, 20, 40, or 80 mg; or pravastatin 10, 20, or 40 mg for 6 weeks. Pairwise comparisons were prospectively planned and performed between rosuvastatin 10, 20, and 40 mg and milligram-equivalent or higher doses of comparators. RESULTS: A total of 2268 patients were randomized to the rosuvastatin 10- to 40-mg, atorvastatin, simvastatin, and pravastatin groups. Fifty-one percent of patients were women, the mean (SD) age was 57 (12) years, and 19% had a documented history of atherosclerotic disease. Over 6 weeks, rosuvastatin significantly reduced non-HDL-C, apo B, and all lipid and apolipoprotein ratios assessed, compared with milligram-equivalent doses of atorvastatin and milligram-equivalent or higher doses of simvastatin and pravastatin (all, P < 0.002). Rosuvastatin reduced non-HDL-C by 42.0% to 50.9% compared with 34.4% to 48.1% with atorvastatin, 26.0% to 41.8% with simvastatin, and 18.6% to 27.4% with pravastatin. Rosuvastatin reduced apo B by 36.7% to 45.3% compared with 29.4% to 42.9% with atorvastatin, 22.2% to 34.7% with simvastatin, and 14.7% to 23.0% with pravastatin. The highest increase in apo A-I (8.8%) was observed in the rosuvastatin 20-mg group, and this increase was significantly greater than in the atorvastatin 40-mg and 80-mg groups (both, P < 0.002). CONCLUSION: Rosuvastatin 10 to 40 mg was more efficacious in improving the lipid profile of patients with hypercholesterolemia than milligram-equivalent doses of atorvastatin and milligram-equivalent or higher doses of simvastatin and pravastatin. |
| Effects of rye bran, oat bran and soya-bean fibre on bile composition, gallstone formation, gall-bladder morphology and serum cholesterol in Syrian golden hamsters (Mesocricetus auratus) Zhang, J. X., E. Lundin, et al. (1994), Br J Nutr 71(6): 861-70. Abstract: The effects of rye bran, oat bran and soya-bean fibre on serum lipids, bile composition and gallstone formation were studied in male Syrian golden hamsters (Mesocricetus auratus). The control groups received fibre-free stone-provoking (O1 diet) or non-stone-provoking (O2 diet) diets. The serum cholesterol levels were lower for all groups fed on the diets supplemented with the dietary fibre sources compared with the control groups. The total content of bile acids in bile was higher in groups given rye-bran diets compared with the corresponding controls. The proportion of cholic acid was higher and that of chenodeoxycholic and lithocholic acid lower in the groups given rye-bran-, oat-bran- or soya-bean-fibre-supplemented diets, compared with the corresponding controls. The secondary:primary bile acid ratio was lower in the group given the rye-bran-supplemented O1 diet. The lithocholic:deoxycholic acid ratio was lower in the groups given rye-bran-, oat-bran- or soya-bean-fibre-supplemented diets than in the corresponding controls. A lower frequency of gallstones was observed only for the group receiving the rye-bran-supplemented O1 diet while the lithogenic index was lower in the groups given the rye-bran-supplemented O2 diet. A decreased epithelial volume density of the gall-bladder and an increased smooth muscular volume density were observed in animals given oat-bran- and rye-bran-supplemented O1 diets, whereas for the soya-bean-fibre-supplemented O1 diet, only the smooth muscular volume density was increased. |
| Effects of S-allyl cysteine sulfoxide isolated from Allium sativum Linn and gugulipid on some enzymes and fecal excretions of bile acids and sterols in cholesterol fed rats Sheela, C. G. and K. T. Augusti (1995), Indian J Exp Biol 33(10): 749-51. Abstract: S-allyl cysteine sulfoxide, isolated from garlic, A. sativum, is more or less as active as gugulipid in controlling hypercholestermia, obesity and derangement of enzyme activities in cholesterol diet fed rats. The beneficial effects of the drugs are partly due to their inhibitory effects on transaminases, alkaline phosphatase, lipogenic enzymes and HMG CoA reductase and partly due to their stimulatory effects on plasma lecithin-cholesterol acyl transferase lipolytic enzymes and fecal excretion of sterols and bile acids. |
| Effects of salmon oil and corn oil on plasma lipid level and hepato-biliary cholesterol metabolism in rats Chautan, M., F. Chanussot, et al. (1990), Biochim Biophys Acta 1046(1): 40-5. Abstract: The aim of this work was to compare the effects of n-3 and n-6 fatty acids on plasma lipid level and hepato-biliary cholesterol metabolism by studying rats fed semi-synthetic diets enriched with either 10% salmon oil, 10% corn oil, or a blend of 6% corn oil and 4% salmon oil. After 4 weeks of feeding, a drop in plasma lipid level was noted in the salmon oil group in comparison to the control group, whereas no change was observed in the corn oil group. An increase in production of cholesterol ester by the liver was recorded in the salmon oil group with a marked enhancement in acyl-CoA:cholesterol acyltransferase (ACAT: EC 2.3.1.26) activity and hepatic cholesterol concentration. Corn oil did not affect either ACAT activity or hepatic cholesterol storage. All bile parameters (flow, bile salts, phospholipids, cholesterol) increased in the salmon oil group, but the molar ratio of cholesterol participation in the bile secretion decreased. These changes in bile composition, as well as in hepatic metabolism of cholesterol, may help to explain the hypolipidemia following the intake of fish oil. |
| Effects of sedentary work on physical fitness and serum cholesterol profile in middle-aged male workers Nagaya, T., Y. Kondo, et al. (2001), Int Arch Occup Environ Health 74(5): 366-70. Abstract: OBJECTIVES: To evaluate independent and interactive health effects of physical activity at work (PAW) and physical activity at habitual exercise (PAHE). METHODS: A cross-sectional study on 1,117 male workers aged 29 to 46 years with a mean of 37.0 years. Using a self-administered questionnaire, the subjects were classified into 'High'/'Low' (n = 338/779) on PAW, and into 'Yes'/'No' (n = 353/764) on PAHE. As outcome indices, physical fitness expressed as maximal oxygen uptake (VO2max) was estimated, and serum total cholesterol (TC), HDL-cholesterol (HDLC) and TC/HDLC ratio were determined. Age, body mass index (kg/m2), alcohol-drinking and smoking were used as confounding factors. RESULTS: The 'High' PAW group had a significantly higher level of VO2max than the 'Low' PAW group (+ 1.0 ml/kg min; 34.4 vs. 33.4 ml/ kg min in adjusted means). The 'High' PAW group also had a better profile of serum cholesterol than the 'Low' PAW group, but it was not significant. The 'Yes' PAHE group had significantly higher levels of VO2max (+ 2.0 ml/kg min; 34.9 vs. 32.9 ml/kg min) and serum HDLC (+0.09 mmol/l; 1.48 vs. 1.39 mmol/l), and a significantly lower TC/HDLC ratio (-0.29; 3.90 vs. 4.19) than the 'No' PAHE group. Among PAW PAHE subgroups, the 'High-Yes' group (n = 110), most physically active, had the best profile of VO2max and serum cholesterol, and the 'Low-No' group (n = 536), least physically active, had the worst one. Interactive effects of PAW and PAHE were not found either on VO2max or on serum cholesterol profile. All the results were not influenced by statistical adjustments for the four confounding factors used here. CONCLUSIONS: Both sedentary work and lack of habitual exercise are very common in Japanese workers. Sedentary work, independently from lack of habitual exercise, may increase the risk of diseases related to physical inactivity by affecting physical fitness and serum cholesterol profile. |
| Effects of selective serotonin reuptake inhibitors on cholesterol levels in patients with panic disorder Bailey, D. L. and J. M. Le Melledo (2003), J Clin Psychopharmacol 23(3): 317-9. |
| Effects of serpins on cholesterol crystallization in model bile Janciauskiene, S., M. C. Gerbord, et al. (1998), J Hepatol 29(4): 541-9. Abstract: BACKGROUND/AIMS: The serine proteinase inhibitors (serpins), alpha-1-antitrypsin (AAT) and alpha-1-antichymotrypsin (ACT), are acute phase proteins synthesized by hepatocytes and excreted to some extent into bile. Their role in gallstone pathogenesis is unclear, and it was the aim of this study to determine their effect on cholesterol crystal growth rate in model bile. METHODS: Purified AAT and ACT were added to model bile at concentrations from 0.5 to 500 microg/ml. Cholesterol crystal growth was analyzed daily by polarizing microscopy and spectrophotometrically at 650 nm. Serpin inhibitory activity was measured spectrophotometrically at 405 nm, and polymerization was studied on 7.5% SDS-PAGE under non-reducing conditions, by immunoelectrophoresis and Western blotting. RESULTS: ACT added to model bile at a concentration of 0.5 microg/ml, inhibited cholesterol crystallization by 30%, had no influence at 5 microg/ml, and increased the crystallization rate 2-3 fold at concentrations of 50 and 500 microg/ml. AAT at a concentration of 0.5 microg/ml had a profound (50%) inhibitory effect on cholesterol crystal growth rate, lacked significant effect at both concentrations of 5 and 50 microg/ml, and showed stimulation of crystal growth up to 30% at a concentration of 500 microg/ml. Both serpins incubated in model bile polymerized and totally lost their inhibitory activity. CONCLUSIONS: Serpins can exhibit both inhibiting and promoting effects on the cholesterol crystallization rate in model bile, dependent on their concentrations. Since AAT and ACT are acute phase proteins, their concentrations may vary under certain pathological conditions, which may result in different actions of these serpins in gallstone formation. |
| Effects of serum storage on the determination of cholesterol Pini, C., D. Sommariva, et al. (1990), Ric Clin Lab 20(1): 37-44. Abstract: Cholesterol determined by 4 different enzymatic commercial kits and by the dry chemistry Reflotron system was higher in serum stored at 4 degrees C and at -20 degrees C than in fresh serum. The effects of storage seem to be temperature-dependent. In fact, cholesterol values significantly increased only after 2h of freezing. The prolongation of freezing up to 2 weeks was not followed by further significant changes. In serum stored at 4 degrees C the increase in cholesterol was slower than in frozen serum. Both free and esterified cholesterol underwent an increase after storage. When cholesterol was determined by a chemical method (sulfuric acid-ferric chloride) after extraction with ethyl acetate and ethanol, no difference was observed in fresh and stored serum. Cholesterol, triglycerides and apoproteins A-I and B underwent parallel changes after storage both in whole serum and fractionated lipoproteins. Our findings strongly suggest that in serum stored at positive or negative temperature there is an alteration of the lipoprotein molecules which allows an easier availability of cholesterol for the enzyme-substrate reaction than in fresh serum. Current enzymatic methods underestimate (about 10%) cholesterol when the analysis is performed on fresh serum. |
| Effects of short-term occupational exposure to lead on erythrocyte glucose-6-phosphate dehydrogenase activity and serum cholesterol Cocco, P., S. Salis, et al. (1995), J Appl Toxicol 15(5): 375-8. Abstract: The effect of short-term occupational exposure to lead on erythrocyte glucose-6-phosphate dehydrogenase (G6PD) activity and serum cholesterol was studied in 40 male workers of a lead and zinc foundry. All parameters were measured just before employment and after 172 +/- 21.3 days of work. Genetic deficiency of erythrocyte G6PD was observed in 5/40 subjects. Among G6PD normal subjects, increases in enzyme activity followed any change (increase or decrease) in blood lead. At the pre-employment test, serum cholesterol parameters did not show any correlation with GOD activity or blood lead, and they were not affected by exposure. Cholesterol values observed among all the GOD-deficient subjects were within the range of the rest of the study population. |
| Effects of short-term reduction in serum cholesterol with simvastatin in patients with stable angina pectoris and mild to moderate hypercholesterolemia de Divitiis, M., P. Rubba, et al. (1996), Am J Cardiol 78(7): 763-8. Abstract: To evaluate the effects of short-term cholesterol-lowering treatment on myocardial effort ischemia, 22 patients with stable effort ischemia and mild to moderate hypercholesterolemia (low density lipoprotein LDL cholesterol 160 to 220 mg/dl) were randomly allocated at baseline (TO) in 2 groups. Group A included 12 patients treated with simvastatin 10 mg bid; group B included 10 patients treated with placebo. All patients underwent a treadmill electrocardiography (ECG) test; total cholesterol, HDL and LDL cholesterol, triglycerides, plasma, and blood viscosity were measured. All tests were repeated after 4 and 12 weeks. For 18 of the same patients (11 taking simvastatin, 7 receiving placebo), forearm strain-gouge plethysmography was performed at baseline and after 4 weeks, both at rest and during reactive hyperemia. At 4 and 12 weeks, group A showed a significant reduction in total cholesterol (p <0.05) and LDL (p <0.05), with unchanged HDL, triglycerides, blood, and plasma viscosity. Effort was unmodified, ST-segment depression at peak effort and ischemic threshold were significantly improved after 4 and 12 weeks (all p <0.05) with unchanged heart rate x systolic blood pressure product. A significant increase in the excess flow response to reactive hyperemia was detected in group A (p <0.03); group B showed no changes in hematochemical and ergometric parameters. These data suggest that cholesterol-lowering treatment is associated with an improvement in myocardial effort ischemia; this might be explained by a more pronounced increase of coronary blood flow and capacity of vasodilation in response to effort. |
| Effects of short-term treatment with pravastatin on the hepatic synthesis of cholesterol and bile acids in gallstone patients Hillebrant, C. G., M. Axelson, et al. (1998), Eur J Clin Invest 28(4): 324-8. Abstract: BACKGROUND: HMG-CoA reductase inhibitors are now the therapy of choice in the treatment of hypercholesterolaemia. The effects of long-term treatment with these substances on plasma lipoproteins, cholesterol metabolism and biliary secretion of lipids have been extensively studied in humans. Much less is known about the effects of short-term treatment. The aim of this study was to determine the time course of the effects of HMG-CoA reductase inhibitors on plasma lipoprotein levels as well as cholesterol and bile acid synthesis in gallstone patients. METHODS: Thirty-six patients undergoing elective cholecystectomy were included in the study. Except for the gallstone disease, these patients were otherwise healthy. Four groups of subjects were treated with the HMG-CoA reductase inhibitor pravastatin (Pravachol), 20 mg twice daily for 12, 24, 48 and 72 h preoperatively. Plasma lipoproteins and plasma levels of lathosterol and 7 alpha-hydroxy-4-cholesten-3-one were determined before initiation of pravastatin treatment and on the morning of the day of the operation, lathosterol reflecting hepatic HMG-CoA reductase activity and 7 alpha-hydroxy-4-cholesten-3-one the activity of cholesterol 7 alpha-hydroxylase, the rate-determining enzyme in bile acid synthesis. RESULTS: All treatment groups displayed a significant decrease in total cholesterol and low-density lipoprotein (LDL)-cholesterol, by about 12% and 17% respectively. Lathosterol was reduced by about 50% in all treatment groups. Of great interest was the finding that 7 alpha-hydroxy-4-cholesten-3-one was unaffected in all treatment groups. CONCLUSION: The results show that short-term pravastatin treatment in gallstone patients rapidly inhibits cholesterol synthesis and lowers plasma LDL-cholesterol levels without effects on bile acid synthesis. |
| Effects of similarities in lifestyle habits on familial aggregation of high density lipoprotein and low density lipoprotein cholesterol: the NHLBI Family Heart Study Ellison, R. C., R. H. Myers, et al. (1999), Am J Epidemiol 150(9): 910-8. Abstract: It is generally assumed that familial aggregation of lipids relates to both genetic and shared environmental factors. To determine the degree to which familial similarities in lifestyle habits explain familial aggregation of high density lipoprotein (HDL) and low density lipoprotein (LDL) cholesterol, the authors analyzed 1994-1996 data from 2,284 US adult participants in the National Heart, Lung, and Blood Institute Family Heart Study. For men and women, respectively, HDL cholesterol correlated with alcohol consumption (r = 0.27, p < 0.001; r = 0.21, p < 0.001), exercise (r = 0.06, p = 0.05; r = 0.10, p = 0.002), and smoking (r = -0.09, p = 0.005; r = -0.13, p < 0.001). There was strong familial aggregation of HDL cholesterol (parent-child, r = 0.32; sibling-sibling, r = 0.29), but less than 10% was explained by lifestyle habits. For LDL cholesterol, weak correlations were found for intake of total fat (r = 0.06, p = 0.07) and fruits/vegetables (r = -0.09, p = 0.005) among men and for smoking (r = 0.10, p = 0.002) among women. LDL cholesterol correlated strongly among family members (parent-child, r = 0.24; sibling-sibling, r = 0.31), but essentially none of this aggregation related to the lifestyle factors studied. This study suggests that lifestyle factors have little effect on the familial aggregation of HDL and LDL cholesterol. |