Cholesterol Articles and Abstracts

For medical practitioners and the general public - Cholesterol Journal Article Catalog.

Cholesterol Journal Articles



Record 12261 to 12280
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The cholesterol non-consensus. Methodological difficulties in the interpretation of epidemiological studies
Berger, M. (1992), Bibl Nutr Dieta(49): 125-30.

The cholesterol papers
Marmot, M. (1994), Bmj 308(6925): 351-2.

The cholesterol profile in the city of Sao Jose do Rio Preto
Nicolau, J. C., D. L. Bechara, et al. (1992), Arq Bras Cardiol 59(6): 433-40.
Abstract: PURPOSE--To analyze: a) the cholesterol profile in adults older than 29 years, from Sao Jose do Rio Preto (300,000 inhabitants), city located in one of the country's richest regions; b) the variables that correlated with cholesterolemia. METHODS--An specialized firm was hired, and data was obtained through quantitative research, where a survey was done, using a sample stratified by sex and age; the error limits admitted was +/- 4%, for a 95% confidence interval, and Reflotron was utilized for cholesterol measurements. It was studied 672 persons (47% men), with mean age of 47.15 +/- 12.28 years; 35% were between 30 and 39 years, 25% between 40 and 49.22% between 50 and 59, and 18% were 60 or more years old. Thirteen variables were compared with cholesterolemia through simple regression; following, six of them, selected as predictors by stepwise regression, were compared with cholesterol through multiple regression analysis. RESULTS--a) Cholesterol levels: 192.5 +/- 48.9 mg/dl on global average, with 187.6 +/- 53.3 for men and 196.8 +/- 44.2 for women (p = 0.01, 95% CI 2.3 to 17.1); 176.5 +/- 44.7 mg/dl for people > or = 30 < 40 years old, 191.3 +/- 51.7 for those > or = 40 < 50 years (p = 0.002, 95% CI 4.6 to 24.2), 206.8 +/- 44.4 for those > or = 50 < 60 years (p = 0.005, 95% CI 4.6 to 26.4), and 208.5 +/- 47.8 for those > or = 60 years (p = 0.765,95% CI 9.5 to -12.5); 62% of the population showed < or = 200 mg/dl, and 16% > or = 240; b) through simple regression analysis, significant correlations were found between cholesterolemia and: age (p < 0.001), systolic (p < 0.001) and diastolic (p < 0.001) arterial pressures, diet (any, the great majority hypocaloric, p = 0.001), height (inverse correlation, p = 0.003), and female gender (p = 0.011); under multiple regression analysis, significant correlations were found for age (p < 0.001), educational level (p < 0.001), systolic arterial pressure (p < 0.001), weight (p = 0.004) and height (inverse correlation, p = 0.012). CONCLUSION--In the population older than 29 years, from Sao Jose do Rio Preto: a) the mean cholesterolemia is 192.5 +/- 48.9 mg/dl, being significantly higher for women, in relation to men, and showing significant increases between 3rd, 4th and 5th decades of life; b) correlated significantly with cholesterolemia, through simple regression analysis: age, systolic and diastolic arterial pressures, diet, height (inverse), and female gender; under multiple regression analysis: age, educational level, systolic arterial pressure, weight and height (inverse).

The cholesterol question. Disinformed information
Bobbio, M. and A. Brusca (1991), G Ital Cardiol 21(9): 1029-33.

The cholesterol requirement for sindbis virus entry and exit and characterization of a spike protein region involved in cholesterol dependence
Lu, Y. E., T. Cassese, et al. (1999), J Virol 73(5): 4272-8.
Abstract: Semliki Forest virus (SFV) and Sindbis virus (SIN) are enveloped alphaviruses that enter cells via low-pH-triggered fusion in the endocytic pathway and exit by budding from the plasma membrane. Previous studies with cholesterol-depleted insect cells have shown that SFV requires cholesterol in the cell membrane for both virus fusion and efficient exit of progeny virus. An SFV mutant, srf-3, shows efficient fusion and exit in the absence of cholesterol due to a single point mutation in the E1 spike subunit, proline 226 to serine. We have here characterized the role of cholesterol in the entry and exit of SIN, an alphavirus quite distantly related to SFV. Growth, primary infection, fusion, and exit of SIN were all dramatically inhibited in cholesterol-depleted cells compared to control cells. Based on sequence differences within the E1 226 region between SFV, srf-3, and SIN, we constructed six SIN mutants with alterations within this region and characterized their cholesterol dependence. A SIN mutant, SGM, that had the srf-3 amino acid sequence from E1 position 224 to 235 showed increases of approximately 100-fold in infection and approximately 250-fold in fusion with cholesterol-depleted cells compared with infection and fusion of wild-type SIN. Pulse-chase analysis demonstrated that SGM exit from cholesterol-depleted cells was markedly more efficient than that of wild-type SIN. Thus, similar to SFV, SIN was cholesterol dependent for both virus entry and exit, and the cholesterol dependence of both steps could be modulated by sequences within the E1 226 region.

The cholesterol to phospholipids ratio (C/PL) of the erythrocyte membrane in normotensive, hypertensive pregnant and in cord blood as assessed by a simple enzymatic method
Piazze Garnica, J. J., F. Pierucci, et al. (1994), Scand J Clin Lab Invest 54(8): 631-5.
Abstract: The study described was conducted to evaluate a simple enzymatic method for the study of the cholesterol/phospholipids ratio in erythrocyte membrane (C/PL) in a group of normal pregnant, of hypertensive pregnant, in non-pregnant controls and in cord blood. Subjects consisted of 28 normotensive pregnant women (NT), 14 women with pregnancy induced hypertension (PIH), 10 non-pregnant normotensive women (Non-Preg) and 14 samples obtained from umbilical cord (C) at delivery from normotensive pregnant. Red blood cells were isolated from heparinated blood samples. Lipids were extracted from erythrocytes by isopropanol/chloroform, without preparation of cell ghosts. Cholesterol content was evaluated by cholesterol oxidase and phospholipids were estimated as organic phosphorus in the total lipid extract. We found a significant difference of C/PL between the PIH group and the NT group (1.01, SD 0.11 vs. 0.76, SD 0.10, 95% CI 0.74-0.78; p < 0.001) and the Non-Preg group (0.83, SD 0.11, 95% CI 0.80-0.86; p < 0.001). Cord blood C/PL was significantly elevated with respect to NT (1.25, SD 0.13 vs. 0.76, SD 0.10; p < 0.001). The method was proven to be fast, reliable and of value for the study of the pathophysiology of the alteration of the lipid composition, i.e., the increased cholesterol content, of the red cell membrane found in hypertensive pregnant patients.

The cholesterol trap: how doctors and patients could avoid overevaluation of a single cholesterol value
Jonsson, G. G., M. Oreberg, et al. (1991), J Clin Epidemiol 44(8): 817-20.

The cholesterol wars
Lach, R. D. (1990), Ohio Med 86(3): 164-5.

The cholesterol/phospholipid ratio of the erythrocyte membrane in children with familial hypercholesterolemia. Its relationship with plasma lipids and red blood cell aggregability
Martinez, M., A. Vaya, et al. (1998), Clin Hemorheol Microcirc 18(4): 259-63.
Abstract: The cholesterol/phospholipid ratio (C/PL) of the red blood cell membrane, plasma lipids and erythrocyte aggregability were evaluated in 20 children with familial hypercholesterolemia (age: 10.4+/-4.6 years) but without detectable vascular injury. The results indicate that hypercholesterolemic children have a higher erythrocyte membrane C/PL ratio than the control group (0.81+/-0.23 vs. 0.65+/-0.08, p < 0.01). This membrane lipid alteration correlates inversely with the plasma concentration of HDL-cholesterol (r = -0.558, p < 0.010). The patients also showed greater erythrocyte aggregability than the control group (8.21+/-1.11 vs. 6.25+/-1.24, p < 0.001), but this does not seem to correlate with the changes observed in the lipid composition of the cell membrane. These results suggest that from childhood, people with familial hyper-cholesterolemia show alterations in the lipid composition of the red blood cell membrane that are related to the changes observed in plasma lipids and appear prior to atherosclerotic vascular symptoms.

The cholesterol-dependent cytolysins
Tweten, R. K., M. W. Parker, et al. (2001), Curr Top Microbiol Immunol 257: 15-33.
Abstract: In view of the recent studies on the CDCs, a reasonable schematic of the stages leading to membrane insertion of the CDCs can be assembled. As shown in Fig. 3, we propose that the CDC first binds to the membrane as a monomer. These monomers then diffuse laterally on the membrane surface to encounter other monomers or incomplete oligomeric complexes. Presumably, once the requisite oligomer size is reached, the prepore complex is converted into the pore complex and a large membrane channel is formed. During the conversion of the prepore complex to the pore complex, we predict that the TMHs of the subunits in the prepore complex insert into the bilayer in a concerted fashion to form the large transmembrane beta-barrel, although this still remains to be confirmed experimentally. Many intriguing problems concerning the cytolytic mechanism of the CDCs remain unsolved. The nature of the initial interaction of the CDC monomer with the membrane is currently one of the most controversial questions concerning the CDC mechanism. Is cholesterol involved in this interaction, as previously assumed, or do specific receptors exist for these toxins that remain to be discovered? Also, the trigger for membrane insertion and the regions of these toxins that facilitate the figure: see text interaction of the monomers during prepore complex formation are unknown. In addition, the temporal sequence of the multiple structural changes that accompany the conversion of the soluble CDC monomer into a membrane-inserted oligomer have yet to be defined or characterized kinetically.

The cholesterol-lowering drug probucol increases apolipoprotein E production in the hippocampus of aged rats: implications for Alzheimer's disease
Champagne, D., D. Pearson, et al. (2003), Neuroscience 121(1): 99-110.
Abstract: Several recent epidemiological studies have proposed that cholesterol-lowering drug Statin may provide protection against Alzheimer's disease (AD). Probucol is a non-Statin cholesterol-lowering drug and a potent inducer of apolipoprotein E (apoE) production in peripheral circulation. A recent clinical study using Probucol in elderly AD subjects revealed a concomitant stabilisation of cognitive symptoms and significant increases in apoE levels in the cerebral spinal fluid in these patients. To gain insight into the mechanisms underlying these effects, we treated a cohort of aged male rats (26-month-old) with oral dose of Probucol for 30 days. Specifically, we examined the effects of Probucol on apoE production and its receptors (low density lipoprotein receptor LDLr and low density lipoprotein receptor-related protein LRP), astroglial marker of cell damage (glial fibrillary acidic protein GFAP), markers of neuronal synaptic plasticity and integrity (synaptosomal associated protein of 25 kDa SNAP-25 and synaptophysin) as well as cholesterol biosynthesis (3-hydroxy-3-methylglutaryl coenzyme A reductase HMGCoAr) in the hippocampus. We report that Probucol induces the production of apoE and one of its main receptors, LRP, increases HMGCoAr (rate-limiting enzyme in cholesterol synthesis), substantially attenuates age-related increases in glial activation, and induces production of synaptic marker SNAP-25, a molecule commonly associated with synaptogenesis and dendritic remodeling.These findings suggest that Probucol could promote neural and synaptic plasticity to counteract the synaptic deterioration associated with brain aging through an apoE/LRP-mediated system. Consistent with the beneficial effects of other cholesterol-lowering drugs such as the Statin, Probucol could also offers additional benefits based on apoE neurobiology.

The cholesterol-lowering effect of a breakfast cereal containing psyllium fibre
Roberts, D. C., A. S. Truswell, et al. (1994), Med J Aust 161(11-12): 660-4.
Abstract: OBJECTIVE: To determine the cholesterol-lowering effect of ready-to-eat cereal containing soluble fibre as psyllium (86%), oatmeal and barley on the plasma lipids of otherwise healthy men with mild hypercholesterolaemia, who were already eating a diet low in saturated fats. DESIGN: Double-blind crossover trial, lasting 12 weeks, in volunteers eating each cereal for six weeks at home, in Sydney and Newcastle (New South Wales). PARTICIPANTS: Eighty-one men (average age 50 years; range, 31-69 years) who had initial plasma (total) cholesterol concentrations of 5.8-8.8 mmol/L, but did not have major illness, obesity or diabetes, and were not on special diets or taking stool bulkers. INTERVENTION: One box of cereal was eaten each day: control, 60 g wheat/wheat bran (2 g soluble fibre); or test, 50 g of product containing psyllium/oats/barley (12 g soluble fibre). Subjects were allocated at random, when established on a low saturated fat diet, to wheat followed by psyllium cereal or psyllium followed by wheat cereal. MAIN OUTCOME MEASURES: Plasma total cholesterol, high density lipoprotein cholesterol, triglyceride and low density lipoprotein cholesterol concentrations measured twice, four to seven days apart before the start of the trial and then after six weeks of eating each cereal. RESULTS: Compliance was excellent with both cereals. There were no significant differences in subjects' macronutrient intake or body weight between the two six-week periods. Total cholesterol and low density lipoprotein cholesterol concentrations fell significantly on psyllium cereal, relative to wheat cereal, in both periods at both centres (mean -3.2% and -4.4%, respectively). There were no consistent changes in triglyceride or high density lipoprotein cholesterol concentrations. CONCLUSIONS: This type of product, which is easy to consume on a daily basis, is a useful adjunct to the dietary management of mild hypercholesterolaemia.

The cholesterol-lowering effect of black beans (Phaseolus vulgaris, L.) without hulls in hypercholesterolemic rats
Rosa, C. O., N. M. Costa, et al. (1998), Arch Latinoam Nutr 48(4): 299-305.
Abstract: The cholesterol-lowering property of beans has been shown in several studies. The propose of the present work was to investigate the effect of black beans (Phaseolus vulgaris, L.) without hulls on blood cholesterol of hypercholesterolemic rats. Four groups of 8 male rats, Wistar strain, initial body weight of 200 g were kept at +/- 25 degrees C in a light-dark cycle of 12 h, for 28 days. The group Standard received a basal casein diet. Group Control received the basal diet added of 1% cholesterol plus 0.1% cholic acid. The group BB received a diet similar to the Control, substituted by 30% black beans, on dry-weight. The group SBB received black beans without hulls, equivalent to 30% of whole beans. The addition of cholesterol and cholic acid raised blood cholesterol levels of rats on Control diet by 58%, in relation to the Standard. BB diet reduced blood cholesterol by 15% (non-significant-NS) and SBB diet reduced (p < 0.05) by 35%, in relation to the Control diet. The levels of HDL-cholesterol were reduced (p < 0.05) by both bean diets. SBB diet promoted a higher excretion of fecal cholesterol, compared to the Control. This suggests that beans without hulls promote a higher cholesterol output and that the whole beans, although had lowered blood cholesterol (NS), kept it in the enterohepatic circulation. The hypocholesterolemic compounds of beans seem to be located in the inner part of the grain. Further studies are necessary to identify these compounds and to elucidate their mechanisms of action.

The cholesterol-lowering effect of black, carioquinha and red beans (Phaseolus vulgaris, L.) in hypercholesterolemic rats
Rosa, C. O., N. M. Costa, et al. (1998), Arch Latinoam Nutr 48(4): 306-10.
Abstract: The propose of the present work was to investigate the cholesterol-lowering effect of black carioquinha and red beans (Phaseolus vulgaris, L.), widely consumed in Brazil, in hypercholesterolemic rats. Five groups of 8 male rats, Wistar strain, initial body weight of 200 g were kept at 25 degrees in a light-dark cycle of 12 h, for 28 days. The group Standard received a basal casein diet. Group Control was formulated by the addition of 1% cholesterol to the basal diet to produce hypercholesterolemia in the rats. The other groups received similar diets to the Control, substituted by 30% black (BB), carioquinha (CB) or red (RB) beans, on dry-weight. The addition of 1% cholesterol promoted an increase of 49% in the levels of total blood cholesterol on Control group, compared with the Standard. The bean diets reduced total blood cholesterol (non-significant): BB reduced 16%, RB 12% and CB 11%, in relation to the Control. The addition of cholesterol to the diets promoted lipid deposition in the rat livers, even in those fed the bean diets. It seems that the reduction of cholesterol in blood is followed by its retention in the rat livers.

The cholesterol-lowering effect of coconut flakes in humans with moderately raised serum cholesterol
Trinidad, T. P., A. S. Loyola, et al. (2004), J Med Food 7(2): 136-40.
Abstract: This study investigated the effect of coconut flakes on serum cholesterol levels of humans with moderately raised serum cholesterol in 21 subjects. The serum total cholesterol of subjects differed and ranged from 259 to 283 mg/dL. The study was conducted in a double-blind randomized crossover design on a 14-week period, consisting of four 2-week experimental periods, with each experimental period separated by a 2-week washout period. The test foods were as follows: corn flakes as the control food, oat bran flakes as the reference food, and corn flakes with 15% and 25% dietary fiber from coconut flakes (made from coconut flour production). Results showed a significant percent reduction in serum total and low-density lipoprotein (LDL) cholesterol (in mg/dL) for all test foods, except for corn flakes, as follows: oat bran flakes, 8.4 +/- 1.4 and 8.8 +/- 6.0, respectively; 15% coconut flakes, 6.9 +/- 1.1 and 11.0 +/- 4.0, respectively; and 25% coconut flakes, 10.8 +/- 1.3 and 9.2 +/- 5.4, respectively. Serum triglycerides were significantly reduced for all test foods: corn flakes, 14.5 +/- 6.3%; oat bran flakes, 22.7 +/- 2.9%; 15% coconut flakes, 19.3 +/- 5.7%; and 25% coconut flakes, 21.8 +/- 6.0%. Only 60% of the subjects were considered for serum triglycerides reduction (serum triglycerides >170 mg/dL). In conclusion, both 15% and 25% coconut flakes reduced serum total and LDL cholesterol and serum triglycerides of humans with moderately raised serum cholesterol levels. Coconut flour is a good source of both soluble and insoluble dietary fiber, and both types of fiber may have significant role in the reduction of the above lipid biomarker. To our knowledge, this is the first study conducted to show a relationship between dietary fiber from a coconut by-product and a lipid biomarker. Results from this study serves as a good basis in the development of coconut flakes/flour as a functional food, justifying the increased production of coconut and coconut by-products.

The cholesterol-lowering effect of guar gum in rats is not accompanied by an interruption of bile acid cycling
Favier, M. L., P. E. Bost, et al. (1998), Lipids 33(8): 765-71.
Abstract: A viscous hydrocolloid (guar gum, GG; 2.5% of the diet) or a steroid sequestrant (cholestyramine; 0.5% of the diet) was included in semipurified diets containing 0.2% cholesterol to compare the cholesterol-lowering effects of each agent in rats. In the present model, GG significantly lowered plasma cholesterol (-25%), especially in the density < 1.040 kg/L fraction, whereas cholestyramine was less potent. Bile acid fecal excretion significantly increased only in rats fed cholestyramine, similar to the cecal bile acid pool; the biliary bile acid secretion was accelerated by GG, but not their fecal excretion, whereas GG effectively enhanced neutral sterol excretion. As a result, the total steroid balance (+13 micromol/d in the control) was shifted toward negative values in rats fed the GG or cholestyramine diets (-27 or -50 micromol/d, respectively). Both agents induced liver 3-hydroxy-3-methylglutaryl-CoA reductase, but cholestyramine was more potent than GG in this respect. The present data suggest that, at a relative low dose in the diet, GG may be more effective than cholestyramine in lowering plasma cholesterol by impairing cholesterol absorption and by accelerating the small intestine/liver cycling of bile acids, which is interestingly, accompanied by reduction of bile acid concentration in the large intestine.

The cholesterol-lowering effect of guar gum is not the result of a simple diversion of bile acids toward fecal excretion
Favier, M. L., P. E. Bost, et al. (1997), Lipids 32(9): 953-9.
Abstract: The effects of partially hydrolyzed, nonviscous, guar gum (PHGG) on cholesterol metabolism and digestive balance have been compared with those of native guar gum (GUAR) in rats adapted to 0.4% cholesterol diets. Both types of guar gum elicited acidic fermentations in the large intestine, but only GUAR effectively lowered plasma cholesterol (P < 0.001), chiefly in the triglyceride-rich lipoprotein fraction. The biliary bile acid excretion was significantly enhanced in rats fed GUAR (P < 0.05), as well as the intestinal and cecal bile acid pool (P < 0.001). In rats fed GUAR and to a lesser extent in those fed PHGG, the fecal excretion of bile acids and neutral sterol was higher than in controls (P < 0.01). The digestive balance (cholesterol intake-steroid excretion) was positive in control rats (+47 mumol/d), whereas it was negative in rats fed GUAR (-20 mumol/d), which could involve a higher rate of endogenous cholesterol synthesis. In rats fed PHGG, the steroid balance remained slightly positive. Liver 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase activity was very low (22 pmol/min/mg protein), owing to cholesterol supplementation, in control rats or in rats fed PHGG, whereas it was markedly higher (+463%) in rats fed GUAR. In conclusion, even if PHGG does alter some parameters of the enterohepatic cycle of cholesterol and bile acids, its effects are not sufficient to elicit a significant cholesterol-lowering effect. The intestinal (ileal or cecal) reabsorption of bile acids was not reduced, but rather increased, by GUAR; nevertheless the intestinal capacities of reabsorption were overwhelmed by the enlargement of the digestive pool of bile acids. In the present model, induction of HMG-CoA reductase probably takes place in the presence of elevated portal bile acid concentrations.

The cholesterol-lowering properties of a psyllium-based breakfast cereal in hamsters
Hicks, V. A., S. C. Chen, et al. (1995), Artery 21(6): 352-61.
Abstract: Hamsters were fed high fiber diets containing cellulose, wheat bran or psyllium. The psyllium was incorporated into high fiber, ready-to-eat (RTE) flakes that were used to formulate the test diet. All the diets contained 0.125% cholesterol. The study was terminated after three weeks. Food intake, weight gain and feed efficiency were not significantly different in the three groups. Serum total and HDL cholesterol levels were reduced significantly by the psyllium diet. Serum triglycerides were 26% lower in the hamsters fed psyllium but because of the large variation the difference did not reach statistical significance. Liver total cholesterol and cholesteryl ester levels were significantly lower in the hamsters fed psyllium. Liver triglycerides were highest in the psyllium-fed hamsters and liver phospholipid levels were similar in the three groups. Liver cholesterol and triglyceride levels were higher in hamsters fed cellulose than in those fed wheat bran. Psyllium formulated into an RTE cereal was effective in reducing serum and liver cholesterol levels in hamsters.

The cholesterol-lowering property of soybeans fed to rats is related to the fasting duration
Guermani-Nicolle, L., C. Villaume, et al. (2001), Plant Foods Hum Nutr 56(3): 239-49.
Abstract: Numerous factors affect plasma cholesterol and, therefore, represent potential interferences with the specific effects of diet on lipid metabolism. After casein intake, serum cholesterol levels depend on many experimental conditions in rats, such as the type of casein, the presence or absence of cholesterol in the diet, the age and strain of rat, the diet composition, the nutritional status. The effect of fasting duration on selected parameters was studied in adult male Wistar rats fed a 20% casein and 1% cholesterol-based diet. No changes were observed in total serum, lipoproteins-B and HDL cholesterol and in triglyceride values after an 8 h-fast compared to non-fasted animals. A significant decrease was induced in total and lipoproteins-B cholesterol with a 12 h-fast. A prolonged fast resulted in a significant decrease in these parameters and in triglycerides and in HDL-cholesterol levels. Fasted animals fed heated soybean meal instead of casein did not display a marked decrease in serum lipids. It appeared that the fasting effect was more marked in animals fed casein than in animals fed soybeans. These results showed the importance of experimental conditions such as nutritional status of animals when blood samples are taken in studies of the hypocholesterolemic effect of soy protein compared to casein.

The cholesterol-raising factor from coffee beans
Urgert, R. and M. B. Katan (1996), J R Soc Med 89(11): 618-23.
Abstract: Coffee beans and some types of coffee brew-not the regular types of coffee prepared with a paper filter or with soluble coffee granules-contain the diterpenes cafestol and kahweol. Cafestol and kahweol raise the serum concentration of cholesterol and triglycerides in humans, and they also appear mildly to affect the integrity of liver cells. Both effects are transient after withdrawal of the diterpenes, and it is as yet unsure whether these effects are associated. Patients at increased risk of heart disease who drink large amounts of coffee should be advised to select brews low in diterpenes.


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