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Sample records for lipoprotein cholesterol modulated

  1. Characterization of biophysical properties of baboon lipoproteins: modulation by dietary fat and cholesterol

    SciTech Connect

    Babiak, J.

    1984-04-01

    The serum lipoproteins of baboons fed diets containing differing types and amounts of fat and varying amounts of cholesterol were examined by analytic ultracentrifugation, gradient gel electrophoresis, density gradient ultracentrifugation, sodium dodecyl sulfate-polyacrylamide electrophoresis, electron microscopy, and standard protein and lipid composition assays. These studies characterized the lipoproteins of the baboon, observed how concentrations and physical-chemical properties of the lipoproteins are modulated by dietary fat and cholesterol and described the suitability of the baboon as an animal model of human lipoprotein metabolism. Results indicate that baboon high density lipoproteins (HDL), though higher in total serum concentration than human HDL, are remarkably similar to human HDL. The concentration of baboon HDL is increased by dietary saturated fat but decreased by the addition of cholesterol. While serum concentrations of low density lipoproteins (LDL) tend to be lower in baboons, the physical-chemical properties of the LDL of baboons and humans are comparable. The LDL of both species contains apolipoprotein B as their major apolipoprotein and exhibit considerable polydispersity in particle size. LDL of both species consists of seven discrete subpopulations. The analytical and statistical data presented in this dissertation indicate that the baboon is a good model for studying the role of lipoproteins in the development of atherosclerosis. 125 references, 31 figures, 28 tables.

  2. Agonistic Human Antibodies Binding to Lecithin-Cholesterol Acyltransferase Modulate High Density Lipoprotein Metabolism.

    PubMed

    Gunawardane, Ruwanthi N; Fordstrom, Preston; Piper, Derek E; Masterman, Stephanie; Siu, Sophia; Liu, Dongming; Brown, Mike; Lu, Mei; Tang, Jie; Zhang, Richard; Cheng, Janet; Gates, Andrew; Meininger, David; Chan, Joyce; Carlson, Tim; Walker, Nigel; Schwarz, Margrit; Delaney, John; Zhou, Mingyue

    2016-02-01

    Drug discovery opportunities where loss-of-function alleles of a target gene link to a disease-relevant phenotype often require an agonism approach to up-regulate or re-establish the activity of the target gene. Antibody therapy is increasingly recognized as a favored drug modality due to multiple desirable pharmacological properties. However, agonistic antibodies that enhance the activities of the target enzymes are rarely developed because the discovery of agonistic antibodies remains elusive. Here we report an innovative scheme of discovery and characterization of human antibodies capable of binding to and agonizing a circulating enzyme lecithin cholesterol acyltransferase (LCAT). Utilizing a modified human LCAT protein with enhanced enzymatic activity as an immunogen, we generated fully human monoclonal antibodies using the XenoMouse(TM) platform. One of the resultant agonistic antibodies, 27C3, binds to and substantially enhances the activity of LCAT from humans and cynomolgus macaques. X-ray crystallographic analysis of the 2.45 Å LCAT-27C3 complex shows that 27C3 binding does not induce notable structural changes in LCAT. A single administration of 27C3 to cynomolgus monkeys led to a rapid increase of plasma LCAT enzymatic activity and a 35% increase of the high density lipoprotein cholesterol that was observed up to 32 days after 27C3 administration. Thus, this novel scheme of immunization in conjunction with high throughput screening may represent an effective strategy for discovering agonistic antibodies against other enzyme targets. 27C3 and other agonistic human anti-human LCAT monoclonal antibodies described herein hold potential for therapeutic development for the treatment of dyslipidemia and cardiovascular disease. PMID:26644477

  3. Agonistic Human Antibodies Binding to Lecithin-Cholesterol Acyltransferase Modulate High Density Lipoprotein Metabolism*

    PubMed Central

    Gunawardane, Ruwanthi N.; Fordstrom, Preston; Piper, Derek E.; Masterman, Stephanie; Siu, Sophia; Liu, Dongming; Brown, Mike; Lu, Mei; Tang, Jie; Zhang, Richard; Cheng, Janet; Gates, Andrew; Meininger, David; Chan, Joyce; Carlson, Tim; Walker, Nigel; Schwarz, Margrit; Delaney, John; Zhou, Mingyue

    2016-01-01

    Drug discovery opportunities where loss-of-function alleles of a target gene link to a disease-relevant phenotype often require an agonism approach to up-regulate or re-establish the activity of the target gene. Antibody therapy is increasingly recognized as a favored drug modality due to multiple desirable pharmacological properties. However, agonistic antibodies that enhance the activities of the target enzymes are rarely developed because the discovery of agonistic antibodies remains elusive. Here we report an innovative scheme of discovery and characterization of human antibodies capable of binding to and agonizing a circulating enzyme lecithin cholesterol acyltransferase (LCAT). Utilizing a modified human LCAT protein with enhanced enzymatic activity as an immunogen, we generated fully human monoclonal antibodies using the XenoMouseTM platform. One of the resultant agonistic antibodies, 27C3, binds to and substantially enhances the activity of LCAT from humans and cynomolgus macaques. X-ray crystallographic analysis of the 2.45 Å LCAT-27C3 complex shows that 27C3 binding does not induce notable structural changes in LCAT. A single administration of 27C3 to cynomolgus monkeys led to a rapid increase of plasma LCAT enzymatic activity and a 35% increase of the high density lipoprotein cholesterol that was observed up to 32 days after 27C3 administration. Thus, this novel scheme of immunization in conjunction with high throughput screening may represent an effective strategy for discovering agonistic antibodies against other enzyme targets. 27C3 and other agonistic human anti-human LCAT monoclonal antibodies described herein hold potential for therapeutic development for the treatment of dyslipidemia and cardiovascular disease. PMID:26644477

  4. Physical inactivity interacts with an endothelial lipase polymorphism to modulate high density lipoprotein cholesterol in the GOLDN study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BACKGROUND: Plasma high density lipoprotein (HDL) cholesterol (HDL-C) concentration is highly heritable but is also modifiable by environmental factors including physical activity. HDL-C response to exercise varies among individuals, and this variability may be associated with genetic polymorphism...

  5. Understanding Lipoproteins as Transporters of Cholesterol and Other Lipids

    ERIC Educational Resources Information Center

    Biggerstaff, Kyle D.; Wooten, Joshua S.

    2004-01-01

    A clear picture of lipoprotein metabolism is essential for understanding the pathophysiology of atherosclerosis. Many students are taught that low-density lipoprotein-cholesterol is "bad" and high-density lipoprotein-cholesterol is "good." This misconception leads to students thinking that lipoproteins are types of cholesterol rather than…

  6. Cholesterol in serum lipoprotein fractions after spaceflight

    NASA Technical Reports Server (NTRS)

    Leach, Carolyn S.; Johnson, Philip C., Jr.; Krauhs, Jane M.; Cintron, Nitza M.

    1988-01-01

    Results are reported from blood-lipid measurements obtained from 125 Space Shuttle crew members before and after space flight. The data are presented in tables and discussed in detail. The main differences noted between preflight and postflight values are a 12.8-percent decrease in high-density lipoproteins on postflight day 1 and significant decreases in total cholesterol and both high- and low-density lipoproteins later in the 23-day postflight period.

  7. Triglycerides, total cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol in rats exposed to premium motor spirit fumes

    PubMed Central

    Aberare, Ogbevire L.; Okuonghae, Patrick; Mukoro, Nathaniel; Dirisu, John O.; Osazuwa, Favour; Odigie, Elvis; Omoregie, Richard

    2011-01-01

    Background: Deliberate and regular exposure to premium motor spirit fumes is common and could be a risk factor for liver disease in those who are occupationally exposed. A possible association between premium motor spirit fumes and plasma levels of triglyceride, total cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol using a rodent model could provide new insights in the pathology of diseases where cellular dysfunction is an established risk factor. Aim: The aim of this study was to evaluate the possible effect of premium motor spirit fumes on lipids and lipoproteins in workers occupationally exposed to premium motor spirit fumes using rodent model. Materials and Methods: Twenty-five Wister albino rats (of both sexes) were used for this study between the 4th of August and 7th of September, 2010. The rats were divided into five groups of five rats each. Group 1 rats were not exposed to premium motor spirit fumes (control group), group 2 rats were exposed for 1 hour daily, group 3 for 3 hours daily, group 4 for 5 hours daily and group 5 for 7 hours daily. The experiment lasted for a period of 4 weeks. Blood samples obtained from all the groups after 4 weeks of exposure were used for the estimation of plasma levels of triglyceride, total cholesterol, high density lipoprotein- cholesterol and low density lipoprotein- cholesterol. Result: Results showed significant increase in means of plasma total cholesterol and low density lipoprotein levels (P<0.05). The mean triglyceride and total body weight were significantly lower (P<0.05) in the exposed group when compared with the unexposed. The plasma level of high density lipoprotein, the ratio of low density lipoprotein to high density lipoprotein and the ratio of total cholesterol to high density lipoprotein did not differ significantly in exposed subjects when compared with the control group. Conclusion: These results showed that frequent exposure to petrol fumes may be highly

  8. A lipoprotein lipase gene polymorphism interacts with consumption of alcohol and unsaturated fat to modulate serum HDL-cholesterol concentrations.

    PubMed

    Baik, Inkyung; Lee, Seungku; Kim, Seong Hwan; Shin, Chol

    2013-10-01

    There are limited data from prospective studies regarding interactions between lipoprotein lipase gene (LPL) and lifestyle factors in association with HDL-cholesterol (HDL-C) concentrations, a biomarker of coronary heart disease risk. Our prospective cohort study investigated the interactive effects of a common LPL polymorphism and lifestyle factors, including obesity, smoking, alcohol consumption, physical activity, and dietary intake, on follow-up measurements of HDL-C and triglyceride (TG) concentrations. A total of 5314 Korean men and women aged 40-69 y participated in the study. Serum HDL-C and TG concentrations were measured in all participants at baseline and 6-y follow-up examinations. On the basis of genome-wide association data for HDL-C and TG concentrations, we selected the most significant polymorphism (rs10503669), which was in high linkage disequilibrium with the serine 447 stop (S447×) mutation (D' = 0.99) of LPL. We found that carrying the T allele reflecting the LPL ×447 allele was positively associated with follow-up measurement of HDL-C concentrations (P < 0.001). In the linear regression model adjusted for baseline HDL-C concentration and potential risk factors, we observed interactive effects of the polymorphism and consumption of alcohol (P-interaction < 0.01) and unsaturated fat (P-interaction < 0.05) on follow-up measurement of HDL-C concentrations. We also observed interactive effects of the polymorphism and body mass index (P-interaction < 0.01) on follow-up measurement of TG concentrations after adjusting for the baseline level and potential risk factors. Our findings suggest that carriers of the LPL ×447 allele benefit from moderate alcohol consumption and a diet high in unsaturated fat to minimize reduction of blood HDL-C concentrations and that obese persons who do not carry the LPL ×447 allele need to control body weight to prevent hypertriglyceridemia.

  9. Total cholesterol, low density lipoprotein cholesterol, and high density lipoprotein cholesterol and coronary heart disease in Scotland.

    PubMed Central

    Hargreaves, A D; Logan, R L; Thomson, M; Elton, R A; Oliver, M F; Riemersma, R A

    1991-01-01

    OBJECTIVE--To investigate long term changes in total cholesterol, high density lipoprotein cholesterol, and low density lipoprotein cholesterol concentrations and in measures of other risk factors for coronary heart disease and to assess their importance for the development of coronary heart disease in Scottish men. DESIGN--Longitudinal study entailing follow up in 1988-9 of men investigated during a study in 1976. SETTING--Edinburgh, Scotland. SUBJECTS--107 men from Edinburgh who had taken part in a comparative study of risk factors for heart disease with Swedish men in 1976 when aged 40. INTERVENTION--The men were invited to attend a follow up clinic in 1988-9 for measurement of cholesterol concentrations and other risk factor measurements. Eighty three attended and 24 refused to or could not attend. MAIN OUTCOME MEASURES--Changes in total cholesterol, high density lipoprotein cholesterol, and low density lipoprotein cholesterol concentrations, body weight, weight to height index, prevalence of smoking, and alcohol intake; number of coronary artery disease events. RESULTS--Mean serum total cholesterol concentration increased over the 12 years mainly due to an increase in the low density lipoprotein cholesterol fraction (from 3.53 (SD 0.09) to 4.56 (0.11) mmol/l) despite a reduction in high density lipoprotein cholesterol concentration. Body weight and weight to height index increased. Fewer men smoked more than 15 cigarettes/day in 1988-9 than in 1976. Blood pressure remained stable and fasting triglyceride concentrations did not change. The frequency of corneal arcus doubled. Alcohol consumption decreased significantly. Eleven men developed clinical coronary heart disease. High low density lipoprotein and low high density lipoprotein cholesterol concentrations in 1976, but not total cholesterol concentration, significantly predicted coronary heart disease (p = 0.05). Almost all of the men who developed coronary heart disease were smokers (91% v 53%, p less than

  10. Limitations of automated remnant lipoprotein cholesterol assay for diagnostic use

    Technology Transfer Automated Retrieval System (TEKTRAN)

    I wish to comment on the limitations of automated remnant lipoprotein cholesterol (RemL-C) assay reported in Clinical Chemistry. Remnants are lipoprotein particles produced after newly formed triglyceride-rich lipoproteins (TRLs) of either hepatic or intestinal origin enter the plasma space and unde...

  11. Six new loci associated with blood low-density lipoprotein cholesterol, high-density lipoprotein cholesterol or triglycerides in humans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol are risk factors for cardiovascular disease and blood triglycerides reflect key metabolic processes including sensitivity to insulin. Blood lipoprotein and lipid concentrations are heritable. To date, the identification o...

  12. Individual Variation in the Effects of Dietary Cholesterol on Plasma Lipoproteins and Cellular Cholesterol Homeostasis in Man

    PubMed Central

    Mistry, P.; Miller, N. E.; Laker, M.; Hazzard, W. R.; Lewis, B.

    1981-01-01

    The effects of dietary cholesterol on plasma lipoproteins and cholesterol homeostasis in blood mononuclear cells have been examined in healthy adults. Addition of 1,500 mg of cholesterol to the daily diet of 37 subjects for 14 d was associated with a wide range of response of plasma total cholesterol concentration (from −6 to +75 mg/dl; mean change, +29 mg/dl; P < 0.001). Increases in plasma cholesterol reflected increased cholesterol concentrations in intermediate density lipoprotein (IDL; 1.006-1.019 g/ml), low density lipoprotein (LDL; 1.019-1.063 g/ml), and the HDL2 subclass (1.063-1.125 g/ml) of high density lipoprotein, which on average accounted for 20, 58, and 22%, respectively, of the total increment. Similar responses occurred in 14 other subjects given 750 mg cholesterol per day for 28 d. Plasma apolipoprotein B concentrations in IDL and LDL also increased. These effects on plasma lipoproteins were accompanied by three changes in freshly isolated blood mononuclear cells: (a) an increase in cell cholesterol content (mean change, +17%; P < 0.01); (b) suppression of 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase activity (−32%; P < 0.001); and (c) reduction of LDL receptor activity (−74%; P < 0.01), quantified as the rate of degradation of 125I-LDL to noniodide trichloroacetic acid-soluble material. These results provide the first direct evidence for the modulation of LDL receptor activity and HMG CoA reductase activity in a peripheral cell type in response to a dietary perturbation of human lipoprotein metabolism. The percentage increase in LDL cholesterol was negatively correlated with the percentage decrease in HMG CoA reductase activity (r = −0.49, P < 0.01). An additional negative correlation existed between the increment in plasma cholesterol concentration and the capacity of cells to degrade 125I-LDL after derepression by preincubation for 72 h in lipoprotein-deficient medium (r = −0.74, P < 0.001). Thus, differences between

  13. Rapid labeling of lipoproteins in plasma with radioactive cholesterol. Application for measurement of plasma cholesterol esterification

    SciTech Connect

    Yen, F.T.; Nishida, T. )

    1990-02-01

    In order to efficiently and rapidly label lipoproteins in plasma with ({sup 3}H)cholesterol, micelles consisting of lysophosphatidylcholine (lysoPC) and ({sup 3}H)cholesterol (molar ratio, 50:1) were prepared. When trace amounts of these micelles were injected into plasma, ({sup 3}H)cholesterol rapidly equilibrated among the plasma lipoproteins, as compared to ({sup 3}H)cholesterol from an albumin-stabilized emulsion. The distributions of both ({sup 3}H)cholesterol and unlabeled free cholesterol in plasma lipoproteins were similar in labeled plasma samples. This method of labeling can be used for the measurement of cholesterol esterification, or lecithin:cholesterol acyltransferase activity, in small amounts (20-40 microliters) of plasma samples.

  14. New micromethod for measuring cholesterol in plasma lipoprotein fractions.

    PubMed

    Bronzert, T J; Brewer, H B

    1977-11-01

    A method is described for the reliable, fast, and relatively inexpensive fractionation of plasma lipoproteins and quantitation of their cholesterol content. This procedure requires 350 microliter of plasma and can be completed within 3 h. Plasma lipoproteins (175 microliter of plasma) were prestained with Fat Red 7B and centrifuged (Beckman Airfuge) at plasma density (d = 1.006 kg/liter) and at a solvent density of 1.060 kg/liter, adjusted by adding solid KBr. Prestained centrifuged samples demonstrated the characteristic elevation of chylomicrons in phenotypes I and V, low-density lipoproteins of phenotype II, very-low-density lipoproteins in phenotype IV and V, and continuum of pink color throughout the centrifuge tube, diagnostic of the floating beta lipoprotein of type III. Centrifuged samples were separated into top and bottom fractions by aspiration. Cholesterol was quantitated with an enzymic oxygen-electrode analyzer (Beckman Cholesterol Analyzer). Correlation coefficients between cholesterol values for plasma from normal hyperlipidemic individuals obtained with the Beckman Analyzer vs. the Technicon AutoAnalyzer II and SMAC systems were 0.977 and 0.973, respectively.

  15. [A history and review of cholesterol ester transfer protein inhibitors and their contribution to the understanding of the physiology and pathophysiology of high density lipoprotein].

    PubMed

    Corral, Pablo; Schreier, Laura

    2014-01-01

    There is irrefutable evidence that statins reduce the risk of cardiovascular events in a magnitude proportional to the intensity of the decrease in cholesterol transport by the low density lipoproteins. Despite this great advance there is still a residual risk of cardiovascular events. For this reason, an increase in the levels of high density lipoprotein is considered in order to boost the main action of this lipoprotein, which is reverse cholesterol transport. Distinct classes of evidence (epidemiological, genetic, and pathophysiological) show that the inhibition and/or modulation of cholesterol ester transfer protein increases plasma high density lipoprotein-cholesterol levels. The main reason for presenting this review is to look at the physiology of cholesterol ester transfer protein, its interrelationship with high density lipoproteins, and to give an update on the development of different cholesterol ester transfer protein inhibitor/modulator molecules. PMID:24094503

  16. [A history and review of cholesterol ester transfer protein inhibitors and their contribution to the understanding of the physiology and pathophysiology of high density lipoprotein].

    PubMed

    Corral, Pablo; Schreier, Laura

    2014-01-01

    There is irrefutable evidence that statins reduce the risk of cardiovascular events in a magnitude proportional to the intensity of the decrease in cholesterol transport by the low density lipoproteins. Despite this great advance there is still a residual risk of cardiovascular events. For this reason, an increase in the levels of high density lipoprotein is considered in order to boost the main action of this lipoprotein, which is reverse cholesterol transport. Distinct classes of evidence (epidemiological, genetic, and pathophysiological) show that the inhibition and/or modulation of cholesterol ester transfer protein increases plasma high density lipoprotein-cholesterol levels. The main reason for presenting this review is to look at the physiology of cholesterol ester transfer protein, its interrelationship with high density lipoproteins, and to give an update on the development of different cholesterol ester transfer protein inhibitor/modulator molecules.

  17. Esterification of Low Density Lipoprotein Cholesterol in Human Fibroblasts and Its Absence in Homozygous Familial Hypercholesterolemia

    PubMed Central

    Goldstein, Joseph L.; Dana, Suzanna E.; Brown, Michael S.

    1974-01-01

    A new mechanism is described for the cellular esterification of cholesterol derived from extra-cellular lipoproteins. Incubation of monolayers of cultured fibroblasts from normal human subjects with low density lipoproteins led to a 30- to 40-fold increase in the rate of incorporation of either [14C]acetate or [14C]oleate into the fatty acid fraction of cholesteryl [14C]esters. This stimulation of cholesteryl ester formation by low density lipoproteins occurred despite the fact that endogenous synthesis of free cholesterol was completely suppressed by the lipoprotein. Thus, exogenous cholesterol contained in low density lipoproteins, rather than endogenously synthesized sterol, appeared to provide the cholesterol substrate for this cellular esterfication process. High density lipoproteins and the lipoprotein-deficient fraction of serum neither stimulated cholesteryl ester formation nor inhibited cholesterol synthesis. Both the low density lipoprotein-dependent increase in cholesterol esterification and decrease in free cholesterol synthesis required the interaction of the lipoprotein with its recently described cell surface receptor. Cells from homozygotes with familial hypercholesterolemia, which lack specific low density lipoprotein receptors, showed neither lipoprotein-dependent cholesterol esterification nor suppression of cholesterol synthesis. The reciprocal changes in free cholesterol synthesis and cholesteryl ester formation produced by low density lipoprotein-receptor interactions may play an important role in the regulation of the cholesterol content of mammalian cells. PMID:4373706

  18. Esterification of low density lipoprotein cholesterol in human fibroblasts and its absence in homozygous familial hypercholesterolemia.

    PubMed

    Goldstein, J L; Dana, S E; Brown, M S

    1974-11-01

    A new mechanism is described for the cellular esterification of cholesterol derived from extra-cellular lipoproteins. Incubation of monolayers of cultured fibroblasts from normal human subjects with low density lipoproteins led to a 30- to 40-fold increase in the rate of incorporation of either [(14)C]acetate or [(14)C]oleate into the fatty acid fraction of cholesteryl [(14)C]esters. This stimulation of cholesteryl ester formation by low density lipoproteins occurred despite the fact that endogenous synthesis of free cholesterol was completely suppressed by the lipoprotein. Thus, exogenous cholesterol contained in low density lipoproteins, rather than endogenously synthesized sterol, appeared to provide the cholesterol substrate for this cellular esterfication process. High density lipoproteins and the lipoprotein-deficient fraction of serum neither stimulated cholesteryl ester formation nor inhibited cholesterol synthesis. Both the low density lipoprotein-dependent increase in cholesterol esterification and decrease in free cholesterol synthesis required the interaction of the lipoprotein with its recently described cell surface receptor. Cells from homozygotes with familial hypercholesterolemia, which lack specific low density lipoprotein receptors, showed neither lipoprotein-dependent cholesterol esterification nor suppression of cholesterol synthesis. The reciprocal changes in free cholesterol synthesis and cholesteryl ester formation produced by low density lipoprotein-receptor interactions may play an important role in the regulation of the cholesterol content of mammalian cells.

  19. High-Density Lipoprotein, Lecithin: Cholesterol Acyltransferase, and Atherosclerosis.

    PubMed

    Ossoli, Alice; Pavanello, Chiara; Calabresi, Laura

    2016-06-01

    Epidemiological data clearly show the existence of a strong inverse correlation between plasma high-density lipoprotein cholesterol (HDL-C) concentrations and the incidence of coronary heart disease. This relation is explained by a number of atheroprotective properties of HDL, first of all the ability to promote macrophage cholesterol transport. HDL are highly heterogeneous and are continuously remodeled in plasma thanks to the action of a number of proteins and enzymes. Among them, lecithin:cholesterol acyltransferase (LCAT) plays a crucial role, being the only enzyme able to esterify cholesterol within lipoproteins. LCAT is synthetized by the liver and it has been thought to play a major role in reverse cholesterol transport and in atheroprotection. However, data from animal studies, as well as human studies, have shown contradictory results. Increased LCAT concentrations are associated with increased HDL-C levels but not necessarily with atheroprotection. On the other side, decreased LCAT concentration and activity are associated with decreased HDL-C levels but not with increased atherosclerosis. These contradictory results confirm that HDL-C levels per se do not represent the functionality of the HDL system. PMID:27302716

  20. High-Density Lipoprotein, Lecithin: Cholesterol Acyltransferase, and Atherosclerosis

    PubMed Central

    Ossoli, Alice; Pavanello, Chiara

    2016-01-01

    Epidemiological data clearly show the existence of a strong inverse correlation between plasma high-density lipoprotein cholesterol (HDL-C) concentrations and the incidence of coronary heart disease. This relation is explained by a number of atheroprotective properties of HDL, first of all the ability to promote macrophage cholesterol transport. HDL are highly heterogeneous and are continuously remodeled in plasma thanks to the action of a number of proteins and enzymes. Among them, lecithin:cholesterol acyltransferase (LCAT) plays a crucial role, being the only enzyme able to esterify cholesterol within lipoproteins. LCAT is synthetized by the liver and it has been thought to play a major role in reverse cholesterol transport and in atheroprotection. However, data from animal studies, as well as human studies, have shown contradictory results. Increased LCAT concentrations are associated with increased HDL-C levels but not necessarily with atheroprotection. On the other side, decreased LCAT concentration and activity are associated with decreased HDL-C levels but not with increased atherosclerosis. These contradictory results confirm that HDL-C levels per se do not represent the functionality of the HDL system. PMID:27302716

  1. Lipoproteins modulate expression of the macrophage scavenger receptor.

    PubMed Central

    Han, J.; Nicholson, A. C.

    1998-01-01

    Macrophage scavenger receptors (MSR) bind and internalize oxidized low density lipoprotein (OxLDL), a modified lipoprotein that is thought to be the proximal source of lipids that accumulate within cells of atherosclerotic lesions. The role of lipoproteins in modulating MSR expression are undetermined. We studied the effect of lipoproteins, native and modified LDL (acetylated LDL (AcLDL) and OxLDL) on the expression of the MSR in RAW cells, a murine macrophage cell line. Exposure to lipoproteins resulted in a marked induction of MSR mRNA expression (12- to 17-fold) with OxLDL and AcLDL having the greatest effects. Maximum induction occurred 1 hour after treatment with OxLDL and LDL. AcLDL induced a fourfold increase at 1 hour followed by a return to baseline and peak expression (sixfold) at 14 hours. Scavenger receptor function, as measured by 125I-AcLDL binding, was only modestly increased in response to lipoproteins. Incubation of macrophages with a cholesterol acceptor particle resulted in a dose-dependent decrease in MSR mRNA expression, which paralleled cholesterol loss from the cells. OxLDL did not affect MSR mRNA stability, implying that MSR mRNA was transcriptionally regulated by lipoproteins. Finally, peritoneal macrophages were isolated from mice following intraperitoneal injection of lipoproteins. Macrophage expression of MSR mRNA was significantly (16-fold) increased by LDL, AcLDL, or OxLDL relative to mice infused with phosphate-buffered saline. This demonstration that exposure to lipoproteins increases expression of the macrophage scavenger receptor implies that lipoproteins can further contribute to foam cell development in atherosclerosis. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:9626069

  2. Pitavastatin versus Pravastatin in Reduction of Remnant Lipoprotein Cholesterol in Patients with Dyslipidemias.

    PubMed

    Roever, Leonardo

    2016-05-01

    Remnant lipoproteins cholesterol are products of partially catabolized chylomicrons and very-low-density lipoprotein, from which some triglycerides have been removed. These particles are smaller and are believed to be strongly atherogenic. Elevated Remnant lipoproteins cholesterol levels were reported to be associated with endothelial dysfunction and atherosclerotic disease.

  3. Acrolein impairs the cholesterol transport functions of high density lipoproteins.

    PubMed

    Chadwick, Alexandra C; Holme, Rebecca L; Chen, Yiliang; Thomas, Michael J; Sorci-Thomas, Mary G; Silverstein, Roy L; Pritchard, Kirkwood A; Sahoo, Daisy

    2015-01-01

    High density lipoproteins (HDL) are considered athero-protective, primarily due to their role in reverse cholesterol transport, where they transport cholesterol from peripheral tissues to the liver for excretion. The current study was designed to determine the impact of HDL modification by acrolein, a highly reactive aldehyde found in high abundance in cigarette smoke, on the cholesterol transport functions of HDL. HDL was chemically-modified with acrolein and immunoblot and mass spectrometry analyses confirmed apolipoprotein crosslinking, as well as acrolein adducts on apolipoproteins A-I and A-II. The ability of acrolein-modified HDL (acro-HDL) to serve as an acceptor of free cholesterol (FC) from COS-7 cells transiently expressing SR-BI was significantly decreased. Further, in contrast to native HDL, acro-HDL promotes higher neutral lipid accumulation in murine macrophages as judged by Oil Red O staining. The ability of acro-HDL to mediate efficient selective uptake of HDL-cholesteryl esters (CE) into SR-BI-expressing cells was reduced compared to native HDL. Together, the findings from our studies suggest that acrolein modification of HDL produces a dysfunctional particle that may ultimately promote atherogenesis by impairing functions that are critical in the reverse cholesterol transport pathway.

  4. Ethanol enhances de novo synthesis of high density lipoprotein cholesterol

    SciTech Connect

    Cluette, J.E.; Mulligan, J.J.; Noring, R.; Doyle, K.; Hojnacki, J.

    1984-05-01

    Male squirrel monkeys fed ethanol at variable doses were used to assess whether alcohol enhances de novo synthesis of high density lipoprotein (HDL) cholesterol in vivo. Monkeys were divided into three groups: 1) controls fed isocaloric liquid diet; 2) low ethanol monkeys fed liquid diet with vodka substituted isocalorically for carbohydrate at 12% of calories; and 3) High Ethanol animals fed diet plus vodka at 24% of calories. High Ethanol primates had significantly higher levels of HDL nonesterified cholesterol than Control and Low Ethanol animals while serum glutamate oxaloacetate transaminase was similar for the three treatments. There were no significant differences between the groups in HDL cholesteryl ester mass or specific activity following intravenous injection of labeled mevalonolactone. By contrast, High Ethanol monkeys had significantly greater HDL nonesterified cholesterol specific activity with approximately 60% of the radioactivity distributed in the HDL/sub 3/ subfraction. This report provides the first experimental evidence that ethanol at 24% of calories induces elevations in HDL cholesterol in primates through enhanced de novo synthesis without adverse effects on liver function.

  5. Cholesterol efflux from THP-1 macrophages is impaired by the fatty acid component from lipoprotein hydrolysis by lipoprotein lipase

    SciTech Connect

    Yang, Yanbo; Thyagarajan, Narmadaa; Coady, Breanne M.; Brown, Robert J.

    2014-09-05

    Highlights: • Lipoprotein hydrolysis products were produced by lipoprotein lipase. • Hydrolysis products lowers expression of macrophage cholesterol transporters. • Hydrolysis products reduces expression of select nuclear receptors. • Fatty acid products lowers cholesterol transporters and select nuclear receptors. • Fatty acid products reduces cholesterol efflux from macrophages. - Abstract: Lipoprotein lipase (LPL) is an extracellular lipase that primarily hydrolyzes triglycerides within circulating lipoproteins. Macrophage LPL contributes to atherogenesis, but the mechanisms behind it are poorly understood. We hypothesized that the products of lipoprotein hydrolysis generated by LPL promote atherogenesis by inhibiting the cholesterol efflux ability by macrophages. To test this hypothesis, we treated human THP-1 macrophages with total lipoproteins that were hydrolyzed by LPL and we found significantly reduced transcript levels for the cholesterol transporters ATP binding cassette transporter A1 (ABCA1), ABCG1, and scavenger receptor BI. These decreases were likely due to significant reductions for the nuclear receptors liver-X-receptor-α, peroxisome proliferator activated receptor (PPAR)-α, and PPAR-γ. We prepared a mixture of free fatty acids (FFA) that represented the ratios of FFA species within lipoprotein hydrolysis products, and we found that the FFA mixture also significantly reduced cholesterol transporters and nuclear receptors. Finally, we tested the efflux of cholesterol from THP-1 macrophages to apolipoprotein A-I, and we found that the treatment of THP-1 macrophages with the FFA mixture significantly attenuated cholesterol efflux. Overall, these data show that the FFA component of lipoprotein hydrolysis products generated by LPL may promote atherogenesis by inhibiting cholesterol efflux, which partially explains the pro-atherogenic role of macrophage LPL.

  6. Membrane cholesterol modulates cochlear electromechanics.

    PubMed

    Brownell, William E; Jacob, Stefan; Hakizimana, Pierre; Ulfendahl, Mats; Fridberger, Anders

    2011-06-01

    Changing the concentration of cholesterol in the plasma membrane of isolated outer hair cells modulates electromotility and prestin-associated charge movement, suggesting that a similar manipulation would alter cochlear mechanics. We examined cochlear function before and after depletion of membrane cholesterol with methyl-β-cyclodextrin (MβCD) in an excised guinea pig temporal bone preparation. The mechanical response of the cochlear partition to acoustic and/or electrical stimulation was monitored using laser interferometry and time-resolved confocal microscopy. The electromechanical response in untreated preparations was asymmetric with greater displacements in response to positive currents. Exposure to MβCD increased the magnitude and asymmetry of the response, without changing the frequency tuning of sound-evoked mechanical responses or cochlear microphonic potentials. Sodium salicylate reversibly blocked the enhanced electromechanical response in cholesterol depleted preparations. The increase of sound-evoked vibrations during positive current injection was enhanced following MβCD in some preparations. Imaging was used to assess cellular integrity which remained unchanged after several hours of exposure to MβCD in several preparations. The enhanced electromechanical response reflects an increase in outer hair cell electromotility and may reveal features of cholesterol distribution and trafficking in outer hair cells. PMID:21373862

  7. Membrane Cholesterol Modulates Superwarfarin Toxicity.

    PubMed

    Marangoni, M Natalia; Martynowycz, Michael W; Kuzmenko, Ivan; Braun, David; Polak, Paul E; Weinberg, Guy; Rubinstein, Israel; Gidalevitz, David; Feinstein, Douglas L

    2016-04-26

    Superwarfarins are modified analogs of warfarin with additional lipophilic aromatic rings, up to 100-fold greater potency, and longer biological half-lives. We hypothesized that increased hydrophobicity allowed interactions with amphiphilic membranes and modulation of biological responses. We find that superwarfarins brodifacoum and difenacoum increase lactate production and cell death in neuroblastoma cells. In contrast, neither causes changes in glioma cells that have higher cholesterol content. After choleterol depletion, lactate production was increased and cell viability was reduced. Drug-membrane interactions were examined by surface X-ray scattering using Langmuir monolayers of dipalmitoylphosphatidylcholine and/or cholesterol. Specular X-ray reflectivity data revealed that superwarfarins, but not warfarin, intercalate between dipalmitoylphosphatidylcholine molecules, whereas grazing incidence X-ray diffraction demonstrated changes in lateral crystalline order of the film. Neither agent showed significant interactions with monolayers containing >20% cholesterol. These findings demonstrate an affinity of superwarfarins to biomembranes and suggest that cellular responses to these agents are regulated by cholesterol content. PMID:27119638

  8. Membrane cholesterol modulates galanin-GalR2 interaction.

    PubMed

    Pang, L; Graziano, M; Wang, S

    1999-09-14

    The neuropeptide galanin mediates a number of diverse physiological and pathophysiological actions via interaction with membrane-bound receptors. The role that membrane cholesterol plays in modulating the interaction between galanin and one of the three cloned galanin receptor subtypes (GalR2) expressed in Chinese hamster ovary (CHO) cells was examined. Reduction of membrane cholesterol by treatment with methyl-beta-cyclodextrin (CD) or by culturing cells in lipoprotein-deficient serum markedly decreased galanin binding to the receptor. Addition of cholesterol back to CD-treated, cholesterol-depleted membranes restored galanin binding to control levels. Hill analysis suggests that the GalR2 binds multiple molecules of cholesterol (n >/= 3) in a positively cooperative manner. This interaction appears to be cholesterol-specific as only cholesterol and a limited number of cholesterol analogues were able to rescue galanin binding. The inability of some of these analogues to rescue the binding activity also suggests that binding of galanin to GalR2 is independent of membrane fluidity as, like cholesterol, cholesterol analogues generally rigidize membranes. In addition, treatment of the membranes with other modulators of membrane fluidity, e.g. ethanol, did not affect galanin binding to the GalR2. In contrast, treatment of membranes, with filipin, a molecule that clusters cholesterol within the membranes, or with cholesterol oxidase resulted in markedly reduced galanin binding. Incubation of membranes with 100 microM GTP-gamma-S did not alter the IC(50) for CD in the prebinding assay treatment suggesting that the effect of cholesterol was independent of G protein interaction. Preincubation of intact cells with CD also drastically impaired the ability of galanin to activate intracellular inositol phosphate accumulation in GalR2-transfected CHO cells. These data detail a new mechanism for the regulation of galanin receptor signaling which may link altered functions of Gal

  9. Reliability of low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol, and apolipoprotein B measurement.

    PubMed

    Contois, John H; Warnick, G Russell; Sniderman, Allan D

    2011-01-01

    There is little understanding of the reliability of laboratory measurements among clinicians. Low-density lipoprotein cholesterol (LDL-C) measurement is the cornerstone of cardiovascular risk assessment and prevention, but it is fraught with error. Therefore, we have reviewed issues related to accuracy and precision for the measurement of LDL-C and the related markers non-high-density lipoprotein cholesterol (non-HDL-C) and apolipoprotein B. Despite the widespread belief that LDL-C is standardized and reproducible, available data suggest that results can vary significantly as the result of methods from different manufacturers. Similar problems with direct HDL-C assays raise concerns about the reliability of non-HDL-C measurement. The root cause of method-specific bias relates to the ambiguity in the definition of both LDL and HDL, and the heterogeneity of LDL and HDL particle size and composition. Apolipoprotein B appears to provide a more reliable alternative, but assays for it have not been as rigorously tested as direct LDL-C and HDL-C assays.

  10. Metabolism of low-density lipoprotein free cholesterol by human plasma lecithin-cholesterol acyltransferase

    SciTech Connect

    Fielding, P.E.; Miida, Takashi; Fielding, C.J. )

    1991-09-03

    The metabolism of cholesterol derived from ({sup 3}H) cholesterol-labeled low-density lipoprotein (LDL) was determined in human blood plasma. LDL-derived free cholesterol first appeared in large {alpha}-migrating HDL (HDL{sub 2}) and was then transferred to small {alpha}-HDL (HDL{sub 3}) for esterification. The major part of such esters was retained within HDL of increasing size in the course of lecithin-cholesterol acyltransferase (LCAT) activity; the balance was recovered in LDL. Transfer of preformed cholesteryl esters within HDL contributed little to the labeled cholesteryl ester accumulating HDL{sub 2}. When cholesterol for esterification was derived instead from cell membranes, a significantly smaller proportion of this cholesteryl ester was subsequently recovered in LDL. These data suggest compartmentation of cholesteryl esters within plasma that have been formed from cell membrane or LDL free cholesterol, and the role for HDL{sub 2} as a relatively unreactive sink for LCAT-derived cholesteryl esters.

  11. Cholesterol efflux from THP-1 macrophages is impaired by the fatty acid component from lipoprotein hydrolysis by lipoprotein lipase.

    PubMed

    Yang, Yanbo; Thyagarajan, Narmadaa; Coady, Breanne M; Brown, Robert J

    2014-09-01

    Lipoprotein lipase (LPL) is an extracellular lipase that primarily hydrolyzes triglycerides within circulating lipoproteins. Macrophage LPL contributes to atherogenesis, but the mechanisms behind it are poorly understood. We hypothesized that the products of lipoprotein hydrolysis generated by LPL promote atherogenesis by inhibiting the cholesterol efflux ability by macrophages. To test this hypothesis, we treated human THP-1 macrophages with total lipoproteins that were hydrolyzed by LPL and we found significantly reduced transcript levels for the cholesterol transporters ATP binding cassette transporter A1 (ABCA1), ABCG1, and scavenger receptor BI. These decreases were likely due to significant reductions for the nuclear receptors liver-X-receptor-α, peroxisome proliferator activated receptor (PPAR)-α, and PPAR-γ. We prepared a mixture of free fatty acids (FFA) that represented the ratios of FFA species within lipoprotein hydrolysis products, and we found that the FFA mixture also significantly reduced cholesterol transporters and nuclear receptors. Finally, we tested the efflux of cholesterol from THP-1 macrophages to apolipoprotein A-I, and we found that the treatment of THP-1 macrophages with the FFA mixture significantly attenuated cholesterol efflux. Overall, these data show that the FFA component of lipoprotein hydrolysis products generated by LPL may promote atherogenesis by inhibiting cholesterol efflux, which partially explains the pro-atherogenic role of macrophage LPL.

  12. Cholesterol efflux from THP-1 macrophages is impaired by the fatty acid component from lipoprotein hydrolysis by lipoprotein lipase.

    PubMed

    Yang, Yanbo; Thyagarajan, Narmadaa; Coady, Breanne M; Brown, Robert J

    2014-09-01

    Lipoprotein lipase (LPL) is an extracellular lipase that primarily hydrolyzes triglycerides within circulating lipoproteins. Macrophage LPL contributes to atherogenesis, but the mechanisms behind it are poorly understood. We hypothesized that the products of lipoprotein hydrolysis generated by LPL promote atherogenesis by inhibiting the cholesterol efflux ability by macrophages. To test this hypothesis, we treated human THP-1 macrophages with total lipoproteins that were hydrolyzed by LPL and we found significantly reduced transcript levels for the cholesterol transporters ATP binding cassette transporter A1 (ABCA1), ABCG1, and scavenger receptor BI. These decreases were likely due to significant reductions for the nuclear receptors liver-X-receptor-α, peroxisome proliferator activated receptor (PPAR)-α, and PPAR-γ. We prepared a mixture of free fatty acids (FFA) that represented the ratios of FFA species within lipoprotein hydrolysis products, and we found that the FFA mixture also significantly reduced cholesterol transporters and nuclear receptors. Finally, we tested the efflux of cholesterol from THP-1 macrophages to apolipoprotein A-I, and we found that the treatment of THP-1 macrophages with the FFA mixture significantly attenuated cholesterol efflux. Overall, these data show that the FFA component of lipoprotein hydrolysis products generated by LPL may promote atherogenesis by inhibiting cholesterol efflux, which partially explains the pro-atherogenic role of macrophage LPL. PMID:25130461

  13. Lysosomal Cholesterol Accumulation Inhibits Subsequent Hydrolysis Of Lipoprotein Cholesteryl Ester

    PubMed Central

    Jerome, W. Gray; Cox, Brian E.; Griffin, Evelyn E.; Ullery, Jody C.

    2010-01-01

    Human macrophages incubated for prolonged periods with mildly oxidized LDL (oxLDL) or cholesteryl ester-rich lipid dispersions (DISP) accumulate free and esterified cholesterol within large, swollen lysosomes similar to those in foam cells of atherosclerosis. The cholesteryl ester (CE) accumulation is, in part, the result of inhibition of lysosomal hydrolysis due to increased lysosomal pH mediated by excessive lysosomal free cholesterol (FC). To determine if the inhibition of hydrolysis was long lived and further define the extent of the lysosomal defect, we incubated THP-1 macrophages with oxLDL or DISP to produce lysosome sterol engorgement and then chased with acetylated LDL (acLDL). Unlike oxLDL or DISP, CE from acLDL normally is hydrolyzed rapidly. Three days of incubation with oxLDL or DISP produced an excess of CE in lipid-engorged lysosomes, indicative of inhibition. After prolonged oxLDL or DISP pretreatment, subsequent hydrolysis of acLDL CE was inhibited. Coincident with the inhibition, the lipid-engorged lysosomes failed to maintain an acidic pH during both the initial pretreatment and subsequent acLDL incubation. This indicates that the alterations in lysosomes were general, long-lived and affected subsequent lipoprotein metabolism. This same phenomenon, occurring within atherosclerotic foam cells, could significantly affect lesion progression. PMID:18312718

  14. The association between occupational lead exposure and serum cholesterol and lipoprotein levels.

    PubMed Central

    Kristal-Boneh, E; Coller, D; Froom, P; Harari, G; Ribak, J

    1999-01-01

    OBJECTIVES: This study sought to clarify the possible associations between blood lead level and serum cholesterol and lipoprotein levels in subjects occupationally exposed to lead. METHODS: Levels of blood lead, serum total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein cholesterol, and triglycerides in 56 male industrial employees who were exposed to lead were compared with those in 87 unexposed employees. RESULTS: Mean blood lead levels were 42.3 (+/- 14.9) micrograms/dL in the exposed group and 2.7 (+/- 3.6) micrograms/dL in the nonexposed group. The exposed subjects had higher mean levels of total cholesterol and HDL cholesterol. CONCLUSIONS: Blood lead levels are positively associated with total and HDL cholesterol. PMID:10394320

  15. Measurement of cholesterol and other lipoprotein constituents in the clinical laboratory.

    PubMed

    Warnick, G R

    2000-04-01

    Measurements of lipids and lipoproteins in the clinical laboratory have become increasingly important because of their predictive association with cardiovascular diseases, especially coronary artery disease. The US National Institutes of Health-sponsored National Cholesterol Education Program and counterparts in other countries have developed national consensus guidelines for diagnosis and treatment of coronary artery disease which provide risk cut-points and define use of the lipid/lipoprotein analytes in case finding and therapy. Total and low density lipoprotein cholesterol and triglycerides are measured as positive risk factors and high density lipoprotein cholesterol as an inverse risk factor for coronary artery disease. A National Cholesterol Education Program-sponsored expert laboratory panel has developed guidelines for measurements with requisite analytical performance targets for total error and corresponding precision and bias. The US Centers for Disease Control and Prevention have established reference methods for total and high density lipoprotein cholesterol and for triglycerides, with a method for low density lipoprotein cholesterol in development. Standardization programs for research laboratories and a Cholesterol Reference Method Laboratory Network for diagnostic manufacturers and clinical laboratories provide reliable access and documentation of traceability to accepted reference methods. Methods for the lipid/lipoprotein analytes have improved dramatically in recent years and, coupled with improved chemistry analyzer systems and more attention to standardization by manufacturers, offer considerable improvement in analytical performance. Fully automated homogeneous assays for high density lipoprotein cholesterol and newer similar assays for low-density lipoprotein cholesterol have potential for better precision as well as more convenient and cost-effective measurements. Attention to pre-analytical sources of variation is also important in making

  16. Linkage between cholesterol 7alpha-hydroxylase and high plasma low-density lipoprotein cholesterol concentrations.

    PubMed Central

    Wang, J; Freeman, D J; Grundy, S M; Levine, D M; Guerra, R; Cohen, J C

    1998-01-01

    Interindividual differences in plasma low-density lipoprotein cholesterol (LDL-C) levels reflect both environmental variation and genetic polymorphism, but the specific genes involved and their relative contributions to the variance in LDL-C are not known. In this study we investigated the relationship between plasma LDL-C concentrations and three genes with pivotal roles in LDL metabolism: the low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), and cholesterol 7alpha-hydroxylase (CYP7). Analysis of 150 nuclear families indicated statistically significant linkage between plasma LDL-C concentrations and CYP7, but not LDLR or APOB. Further sibling pair analyses using individuals with high plasma LDL-C concentrations as probands indicated that the CYP7 locus was linked to high plasma LDL-C, but not to low plasma LDL-C concentrations. This finding was replicated in an independent sample. DNA sequencing revealed two linked polymorphisms in the 5' flanking region of CYP7. The allele defined by these polymorphisms was associated with increased plasma LDL-C concentrations, both in sibling pairs and in unrelated individuals. Taken together, these findings indicate that polymorphism in CYP7 contributes to heritable variation in plasma LDL-C concentrations. Common polymorphisms in LDLR and APOB account for little of the heritable variation in plasma LDL-C concentrations in the general population. PMID:9502769

  17. Effects of diet on high-density lipoprotein cholesterol.

    PubMed

    Siri-Tarino, Patty W

    2011-12-01

    Multiple dietary factors have been shown to increase high-density lipoprotein cholesterol (HDL-C) concentrations, and HDL-C has been inversely associated with coronary heart disease (CHD) risk. Replacement of dietary carbohydrate with polyunsaturated, monounsaturated and saturated fat has been associated with progressively greater increases in HDL-C (7-12%) in addition to other lipid changes. Added sugars, but not high glycemic carbohydrates, have been associated with decreased HDL-C. Alcohol consumption has been associated with increased HDL-C (9.2%) independent of changes in other measured lipids. Modest effects on HDL-C (~4-5%) among other lipid and non-lipid CHD risk factors have also been observed with weight loss by dieting, omega-3 fatty acids, and a Mediterranean diet pattern. The CHD benefit of increasing HDL-C is unclear given the inconsistent evidence from HDL-raising pharmacologic trials. Furthermore, pleiotropic effects of diet preclude attribution of CHD benefit specifically to HDL-C. Investigation into functional or other properties of HDL may lend further insight. PMID:21901431

  18. Novel Therapies for Low-Density Lipoprotein Cholesterol Reduction.

    PubMed

    Toth, Peter P

    2016-09-15

    Although many clinical trials and meta-analyses have demonstrated that lower serum low-density lipoprotein cholesterol (LDL-C) levels are associated with proportionately greater reductions in the risk of cardiovascular disease events, not all patients with hypercholesterolemia are able to attain risk-stratified LDL-C goals with statin monotherapy. Elucidation of the pathophysiology of genetic disorders of lipid metabolism (e.g., familial hypercholesterolemia) has led to the development of several novel lipid-lowering strategies, including blocking the degradation of hepatic LDL-C receptors that are important in LDL-C clearance, or the inhibition of apoprotein synthesis and lipidation. Mipomersen and lomitapide are highly efficacious new agents available for the treatment of patients with homozygous familial hypercholesterolemia. The recent introduction of PCSK9 inhibitors (alirocumab and evolocumab) have made it possible for many patients to achieve very low LDL-C concentrations (e.g., <40 mg/dl) that are usually not attainable with statin monotherapy. Ongoing clinical trials are examining the impact of very low LDL-C levels on cardiovascular disease event rates and the long-term safety of this approach. PMID:27620356

  19. Measurement of low-density lipoprotein cholesterol in assessment and management of cardiovascular disease risk.

    PubMed

    Jialal, I; Remaley, A T

    2014-07-01

    The deposition of cholesterol in the arterial wall by the infiltration of low-density lipoproteins (LDLs) is a key step in the development of atherosclerosis. In this Commentary, we discuss recent recommendations for clinical laboratory measurement of low-density lipoprotein cholesterol (LDL-C) and its utility both for assessing cardiovascular disease risk and as a tool in the management of patients receiving lipid-lowering therapy.

  20. Relative atherogenicity and predictive value of non-high-density lipoprotein cholesterol for coronary heart disease.

    PubMed

    Miller, Michael; Ginsberg, Henry N; Schaefer, Ernst J

    2008-04-01

    Although low-density lipoprotein cholesterol (LDL-C) is a well-established atherogenic factor for coronary heart disease, it does not completely represent the risk associated with atherogenic lipoproteins in the presence of high triglyceride (TG) levels. Constituent lipoproteins constituting non-high-density lipoprotein cholesterol (non-HDL-C) include atherogenic TG-rich lipoproteins, cholesteryl ester-enriched remnants of TG-rich lipoproteins, and lipoprotein(a). Recent observational and intervention studies suggest that the predictive value of non-HDL-C for cardiovascular risk and mortality is better than low-density lipoprotein cholesterol and that non-HDL-C correlates highly with plasma apolipoprotein B levels. Currently, the National Cholesterol Education Program Adult Treatment Panel III guidelines identify non-HDL-C as a secondary target of therapy in patients with TG elevation (> or =200 mg/dl) after the attainment of LDL-C target goals. In patients with coronary heart disease or coronary heart disease risk equivalents, an optional non-HDL-C goal is <100 mg/dl. To achieve the non-HDL-C goal, statin therapy may be intensified or combined with ezetimibe, niacin, a fibrate, or omega-3 fatty acids. In conclusion, non-HDL-C remains an important target of therapy for patients with elevated TGs, although its widespread adoption has yet to gain a foothold among health care professionals treating patients with dyslipidemia. PMID:18359322

  1. High-density lipoprotein cholesterol on a roller coaster: where will the ride end?

    PubMed

    Kronenberg, Florian

    2016-04-01

    Bowe et al. report an association between low high-density lipoprotein cholesterol concentrations and various incident chronic kidney disease end points in a cohort of almost 2 million US veterans followed for 9 years. These impressive data should be a starting point for further investigations including genetic epidemiologic investigations as well as post hoc analyses of interventional trials that target high-density lipoprotein cholesterol and, finally, studies that focus on the functionality of high-density lipoprotein particles. PMID:26994572

  2. Total and High-Density Lipoprotein Cholesterol in Adults with Mental Retardation.

    ERIC Educational Resources Information Center

    Rimmer, James H.; Kelly, Luke E.

    1990-01-01

    The study evaluated the total cholesterol and high density lipoprotein cholesterol of 40 adults (mean age 37.5 years) with mental retardation residing at an intermediate care facility. Results indicated that 59 percent of the males and 68 percent of the females were at moderate to high risk for coronary heart disease. (DB)

  3. Modifying plasma low-density lipoprotein and high-density lipoprotein cholesterol: what combinations are available in the future?

    PubMed

    Kastelein, John J P

    2005-11-01

    Despite a growing body of research on the benefit of combination drug therapy for dyslipidemia in the metabolic syndrome or diabetes mellitus, there are insufficient outcome data on the use of combination therapy as well as inadequate data to compare certain combination regimens. The focus of the therapeutic approach in treating the metabolic syndrome has been almost exclusively on low-density lipoprotein (LDL) cholesterol for approximately the past 10 years, and specifically on statin therapy. Although results of epidemiologic studies as well as clinical trials using angiographic and clinical end points confirm the association of LDL cholesterol and risk of coronary artery disease, data are lacking regarding the effects of combination therapy in the management of coronary artery disease. Management of the metabolic syndrome focusing on the modification of plasma LDL as well as high-density lipoprotein cholesterol is reviewed. Future management strategies with the use of novel combination therapy is also discussed. PMID:16291010

  4. Rhesus positivity and low high-density lipoprotein cholesterol: a new link?

    PubMed

    Kanbay, Mehmet; Yildirir, Aylin; Ulus, Taner; Bilgi, Muhammet; Kucuk, Alparslan; Muderrisoglu, Haldun

    2006-04-01

    The aim of the study was to investigate the relationship of ABO and Rh blood groups with lipid profile in patients with established multivessel coronary artery disease in a population with low levels of high-density lipoprotein cholesterol. The records of 978 patients with multivessel coronary artery disease, in whom coronary bypass surgery was performed, were investigated. Coronary risk factors including diabetes, hypertension, smoking, and obesity were noted for each patient. Serum lipid profiles: total cholesterol, low-density and high-density lipoprotein cholesterol, and triglyceride levels, were also recorded. The mean age of the patients was 59.3 +/- 9.7 years (range, 25-84 years) and 80% were male. The risk factors and lipid profiles of ABO blood types were similar. Rh-negative patients had higher levels of high-density lipoprotein cholesterol (46.9 +/- 9.9 vs. 41.6 +/- 10.4 mg.dL(-1), p = 0.001) and a lower total/high-density lipoprotein cholesterol ratio (4.8 +/- 1.3 vs. 5.2 +/- 1.6, p = 0.029) compared to Rh-positive patients. The other lipid levels and risk factors had no association with Rh typing. These results indicate a significant association between rhesus positivity and low levels of high-density lipoprotein cholesterol in patients with multivessel coronary artery disease.

  5. Detergent-Mediated Phospholipidation of Plasma Lipoproteins Increases HDL Cholesterophilicity and Cholesterol Efflux Via SR-BI†

    PubMed Central

    Pownall, Henry J.

    2008-01-01

    Cellular cholesterol efflux is an early, obligatory step in reverse cholesterol transport, the putative antiatherogenic mechanism by which human plasma high density lipoproteins (HDL) transport cholesterol from peripheral tissue to the liver for recycling or disposal. HDL-phospholipid content is the essential cholesterol-binding component of lipoproteins and therefore a major determinant of cholesterol efflux. Thus, increased phospholipidation of lipoproteins, particularly HDL, is one strategy for increasing cholesterol efflux. This study validates a simple, new detergent perturbation method for the phospholipidation of plasma lipoproteins; we have quantified the cholesterophilicity of human plasma lipoproteins and the effects of lipoprotein phospholipidation on cholesterophilicity and cellular cholesterol efflux mediated by the class B type I scavenger receptor (SR-BI). We determined that low density lipoproteins (LDL) are more cholesterophilic than HDL and that LDL has a higher affinity for phospholipids than HDL whereas HDL has a higher phospholipid capacity than LDL. Phospholipidation of total human plasma lipoproteins enhances cholesterol efflux, an effect that occurs largely through the preferential phospholipidation of HDL. We conclude that increasing HDL phospholipid increases its cholesterophilicity thereby making it a better acceptor of cellular cholesterol efflux. Phospholipidation of lipoproteins by detergent perturbation is a simple way to increase HDL cholesterophilicity and cholesterol efflux in a way that may be clinically useful. PMID:16981711

  6. Reliability of Calculated Low-Density Lipoprotein Cholesterol.

    PubMed

    Meeusen, Jeffrey W; Snozek, Christine L; Baumann, Nikola A; Jaffe, Allan S; Saenger, Amy K

    2015-08-15

    Aggressive low-density lipoprotein cholesterol (LDL-C)-lowering strategies are recommended for prevention of cardiovascular events in high-risk populations. Guidelines recommend a 30% to 50% reduction in at-risk patients even when LDL-C concentrations are between 70 and 130 mg/dl (1.8 to 3.4 mmol/L). However, calculation of LDL-C by the Friedewald equation is the primary laboratory method for routine LDL-C measurement. We compared the accuracy and reproducibility of calculated LDL-C <130 mg/dl (3.4 mmol/L) to LDL-C measured by β quantification (considered the gold standard method) in 15,917 patients with fasting triglyceride concentrations <400 mg/dl (4.5 mmol/L). Both variation and bias of calculated LDL-C increased at lower values of measured LDL-C. The 95% confidence intervals for a calculated LDL-C of 70 mg/dl (1.8 mmol/L) and 30 mg/dl (0.8 mmol/L) were 60 to 86 mg/dl (1.6 to 2.2 mmol/L) and 24 to 60 mg/dl (0.6 to 1.6 mmol/L), respectively. Previous recommendations have emphasized the requirement for a fasting sample with triglycerides <400 mg/dl (4.5 mmol/L) to calculate LDL-C by the Friedewald equation. However, no recommendations have addressed the appropriate lower reportable limit for calculated LDL-C. In conclusion, calculated LDL-C <30 mg/dl (0.8 mmol/L) should not be reported because of significant deviation from the gold standard measured LDL-C results, and caution is advised when using calculated LDL-CF values <70 mg/dl (1.8 mmol/L) to make treatment decisions.

  7. Lipoprotein Subfraction Cholesterol Distribution Is Proatherogenic in Women With Type 1 Diabetes and Insulin Resistance

    PubMed Central

    Maahs, David M.; Hokanson, John E.; Wang, Hong; Kinney, Gregory L.; Snell-Bergeon, Janet K.; East, Ashley; Bergman, Bryan C.; Schauer, Irene E.; Rewers, Marian; Eckel, Robert H.

    2010-01-01

    OBJECTIVE Individuals with type 1 diabetes have a less atherogenic fasting lipid profile than those without diabetes but paradoxically have increased rates of cardiovascular disease (CVD). We investigated differences in lipoprotein subfraction cholesterol distribution and insulin resistance between subjects with and without type 1 diabetes to better understand the etiology of increased CVD risk. RESEARCH DESIGN AND METHODS Fast protein liquid chromatography was used to fractionate lipoprotein cholesterol distribution in a substudy of the Coronary Artery Calcification in Type 1 Diabetes (CACTI) study (n = 82, age 46 ± 8 years, 52% female, 49% with type 1 diabetes for 23 ± 8 years). Insulin resistance was assessed by a hyperinsulinemic-euglycemic clamp. RESULTS Among men, those with type 1 diabetes had less VLDL and more HDL cholesterol than control subjects (P < 0.05), but among women, those with diabetes had a shift in cholesterol to denser LDL, despite more statin use. Among control subjects, men had more cholesterol distributed as VLDL and LDL but less as HDL than women; however, among those with type 1 diabetes, there was no sex difference. Within sex and diabetes strata, a more atherogenic cholesterol distribution by insulin resistance was seen in men with and without diabetes, but only in women with type 1 diabetes. CONCLUSIONS The expected sex-based less atherogenic lipoprotein cholesterol distribution was not seen in women with type 1 diabetes. Moreover, insulin resistance was associated with a more atherogenic lipoprotein cholesterol distribution in all men and in women with type 1 diabetes. This lipoprotein cholesterol distribution may contribute to sex-based differences in CVD in type 1 diabetes. PMID:20393149

  8. Baseline lipoprotein lipids and low-density lipoprotein cholesterol response to prescription omega-3 acid ethyl ester added to Simvastatin therapy.

    PubMed

    Maki, Kevin C; Dicklin, Mary R; Davidson, Michael H; Doyle, Ralph T; Ballantyne, Christie M

    2010-05-15

    The present post hoc analysis of data from the COMBination of prescription Omega-3 with Simvastatin (COMBOS) study investigated the predictors of the low-density lipoprotein (LDL) cholesterol response to prescription omega-3 acid ethyl ester (P-OM3) therapy in men and women with high (200 to 499 mg/dl) triglycerides during diet plus simvastatin therapy. Subjects (n = 256 randomized) received double-blind P-OM3 4 g/day or placebo for 8 weeks combined with diet and open-label simvastatin 40 mg/day. The percentage of changes from baseline (with diet plus simvastatin) in lipids was evaluated by tertiles of baseline LDL cholesterol and triglyceride concentrations. The baseline LDL cholesterol tertile was a significant predictor of the LDL cholesterol response (p = 0.022 for the treatment by baseline tertile interaction). The median LDL cholesterol response in the P-OM3 group was +9.5% (first tertile, <80.4 mg/dl), -0.9% (second tertile), and -6.4% (third tertile, > or =99.0 mg/dl). Non-high-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglyceride responses did not vary significantly by baseline LDL cholesterol tertile. The reductions in very-low-density lipoprotein cholesterol concentrations were greater than the increases in LDL cholesterol, where present, resulting in a net decrease in the concentration of cholesterol carried by atherogenic particles (non-high-density lipoprotein cholesterol) in all baseline LDL cholesterol tertiles. In conclusion, these results suggest that the increase in LDL cholesterol that occurred with the addition of P-OM3 to simvastatin therapy in subjects with mixed dyslipidemia was confined predominantly to those with low LDL cholesterol levels while receiving simvastatin monotherapy. PMID:20451686

  9. Dietary cholesterol and the plasma lipids and lipoproteins in the Tarahumara Indians: a people habituated to a low cholesterol diet after weaning.

    PubMed

    McMurry, M P; Connor, W E; Cerqueira, M T

    1982-04-01

    Eight Tarahumara Indian men participated in a metabolic study to measure the responsiveness of their plasma cholesterol levels to dietary cholesterol. They were fed isocaloric cholesterol-free and high cholesterol diets containing 20% fat, 15% protein, and 65% carbohydrate calories. On admission to the study, the Tarahumaras had a low mean plasma cholesterol concentration (120 mg/dl), reflecting their habitual low cholesterol diet. After 3 wk of a cholesterol-free diet their cholesterol levels were 113 mg/dl. The men were then fed a high cholesterol diet (1000 mg/day) which increased the mean total plasma cholesterol to 147 mg/dl (p less than 0.01) and also increased the low-density lipoprotein cholesterol concentration. Tarahumaras, habituated to a low cholesterol diet after weaning, had the typical hypercholesterolemic response to a high cholesterol diet that has been previously observed in subjects whose lifelong diet was high in cholesterol content.

  10. LCAT synthesized by primary astrocytes esterifies cholesterol on glia-derived lipoproteins

    PubMed Central

    Hirsch-Reinshagen, Veronica; Donkin, James; Stukas, Sophie; Chan, Jennifer; Wilkinson, Anna; Fan, Jianjia; Parks, John S.; Kuivenhoven, Jan Albert; Lütjohann, Dieter; Pritchard, Haydn; Wellington, Cheryl L.

    2009-01-01

    Lipid trafficking in the brain is essential for the maintenance and repair of neuronal membranes, especially after neurotoxic insults. However, brain lipid metabolism is not completely understood. In plasma, LCAT catalyses the esterification of free cholesterol on circulating lipoproteins, a key step in the maturation of HDL. Brain lipoproteins are apolipoprotein E (apoE)-containing, HDL-like particles secreted initially as lipid-poor discs by glial cells. LCAT is synthesized within the brain, suggesting that it may play a key role in the maturation of these lipoproteins. Here we demonstrate that astrocytes are the primary producers of brain LCAT. This LCAT esterifies free cholesterol on nascent apoE-containing lipopoproteins secreted from glia. ApoE is the major LCAT activator in glia-conditioned media (GCM), and both the cholesterol transporter ABCA1 and apoE are required to generate glial LCAT substrate particles. LCAT deficiency leads to the appearance of abnormal ∼8 nm particles in GCM, and exogenous LCAT restores the lipoprotein particle distribution to the wild-type (WT) pattern. In vivo, complete LCAT deficiency results in a dramatic increase in apoE-HDL and reduced apolipoprotein A-I (apoA-I)-HDL in murine cerebrospinal fluid (CSF). These data show that brain LCAT esterifies cholesterol on glial-derived apoE-lipoproteins, and influences CSF apoE and apoA-I levels. PMID:19065001

  11. Focus on lipids: high-density lipoprotein cholesterol and its associated lipoproteins in cardiac and renal disease.

    PubMed

    Shin, Hyun Joon; McCullough, Peter A

    2014-01-01

    High-density lipoprotein cholesterol (HDL-C) contains dozens of apoproteins that participate in normal cholesterol metabolism with a reliance on renal catabolism for clearance from the body. The plasma pool of HDL-C has been an excellent inverse predictor of cardiovascular events. However, when HDL-C concentrations have been manipulated with the use of niacin, fibric acid derivatives, and cholesteryl ester transferase protein inhibitors, there has been no improvement in outcomes in patients where the low-density lipoprotein cholesterol has been well treated with statins. Apolipoprotein L1 (APOL1) is one of the minor apoproteins of HDL-C, newly discovered in 1997. Circulating APOL1 is a 43-kDa protein mainly found in the HDL3 subfraction. In patients with chronic kidney disease (CKD), mutant forms of APOL1 have been associated with rapidly progressive CKD and end-stage renal disease (ESRD). Because mutant forms of APOL1 are more prevalent in African Americans compared to Caucasians, it may explain some of the racial disparities seen in the pool of patients with ESRD in the United States. Thus, HDL-C is an important lipoprotein carrying apoproteins that play roles in vascular and kidney disease. PMID:25343842

  12. Evidence for several independent genetic variants affecting lipoprotein (a) cholesterol levels

    PubMed Central

    Lu, Wensheng; Cheng, Yu-Ching; Chen, Keping; Wang, Hong; Gerhard, Glenn S.; Still, Christopher D.; Chu, Xin; Yang, Rongze; Parihar, Ankita; O'Connell, Jeffrey R.; Pollin, Toni I.; Angles-Cano, Eduardo; Quon, Michael J.; Mitchell, Braxton D.; Shuldiner, Alan R.; Fu, Mao

    2015-01-01

    Lipoprotein (a) [Lp(a)] is an independent risk factor for atherosclerosis-related events that is under strong genetic control (heritability = 0.68–0.98). However, causal mutations and functional validation of biological pathways modulating Lp(a) metabolism are lacking. We performed a genome-wide association scan to identify genetic variants associated with Lp(a)-cholesterol levels in the Old Order Amish. We confirmed a previously known locus on chromosome 6q25-26 and found Lp(a) levels also to be significantly associated with a SNP near the APOA5–APOA4–APOC3–APOA1 gene cluster on chromosome 11q23 linked in the Amish to the APOC3 R19X null mutation. On 6q locus, we detected associations of Lp(a)-cholesterol with 118 common variants (P = 5 × 10−8 to 3.91 × 10−19) spanning a ∼5.3 Mb region that included the LPA gene. To further elucidate variation within LPA, we sequenced LPA and identified two variants most strongly associated with Lp(a)-cholesterol, rs3798220 (P = 1.07 × 10−14) and rs10455872 (P = 1.85 × 10−12). We also measured copy numbers of kringle IV-2 (KIV-2) in LPA using qPCR. KIV-2 numbers were significantly associated with Lp(a)-cholesterol (P = 2.28 × 10−9). Conditional analyses revealed that rs3798220 and rs10455872 were associated with Lp(a)-cholesterol levels independent of each other and KIV-2 copy number. Furthermore, we determined for the first time that levels of LPA mRNA were higher in the carriers than non-carriers of rs10455872 (P = 0.0001) and were not different between carriers and non-carriers of rs3798220. Protein levels of apo(a) were higher in the carriers than non-carriers of both rs10455872 and rs3798220. In summary, we identified multiple independent genetic determinants for Lp(a)-cholesterol. These findings provide new insights into Lp(a) regulation. PMID:25575512

  13. Influence of total cholesterol, high density lipoprotein cholesterol, and triglycerides on risk of cerebrovascular disease: the Copenhagen City Heart Study.

    PubMed Central

    Lindenstrøm, E.; Boysen, G.; Nyboe, J.

    1994-01-01

    OBJECTIVE--To estimate the influence of plasma total cholesterol, high density lipoprotein cholesterol, and triglycerides on risk of cerebrovascular disease. DESIGN--The Copenhagen City Heart Study is a prospective observational survey with two cardiovascular examinations at five year intervals. Non-fasting plasma lipids were measured in participants once at each examination, along with other variables. The Cox regression model was used to establish the effect of the factors recorded on cerebrovascular events of mostly, but not exclusively, ischaemic origin. SUBJECTS--19,698 women and men at least 20 years old, randomly selected after age stratification from an area of central Copenhagen. MAIN OUTCOME MEASURES--Initial cases of stroke and transient ischaemic attack recorded from hospital records and death certificates from 1976 through 1988. RESULTS--660 non-haemorrhagic and 33 haemorrhagic events were recorded. Total cholesterol was positively associated with risk of non-haemorrhagic events, but only for levels > 8 mmol/l, corresponding to the upper 5% of the distribution in the study population. For lower plasma cholesterol values the relative risk remained nearly constant. Plasma triglyceride concentration was significantly, positively associated with risk of non-haemorrhagic events. The relative risk corresponding to an increase of 1 mmol/l was 1.12 (95% confidence interval 1.07 to 1.16). There was a negative, log linear association between high density lipoprotein cholesterol and risk of non-haemorrhagic events (0.53 (0.34 to 0.83)). There was no indication that the effects of plasma lipids were different in women and men. CONCLUSIONS--The pattern of the association between plasma cholesterol and risk of ischaemic cerebrovascular disease was not log linear, and the increased risk was confined to the upper 5% of the cholesterol distribution. Further studies should concentrate on the association between plasma cholesterol and verified haemorrhagic stroke. PMID

  14. Associations between Serum 25-hydroxyvitamin D and Lipids, Lipoprotein Cholesterols, and Homocysteine

    PubMed Central

    Glueck, Charles J.; Jetty, Vybhav; Rothschild, Matan; Duhon, Gregory; Shah, Parth; Prince, Marloe; Lee, Kevin; Goldenberg, Michael; Kumar, Ashwin; Goldenberg, Naila; Wang, Ping

    2016-01-01

    Background: Serum 25(OH) vitamin D levels are inversely associated with cardiovascular disease (CVD) mortality, mediated in part by independent positive relationships with high-density lipoprotein cholesterol (HDLC) and inverse relationships with low-density lipoprotein cholesterol (LDLC), triglyceride, and homocysteine. Aims: In this study, we assessed relationships between fasting serum vitamin D and lipids, lipoprotein cholesterols, and homocysteine. Materials and Methods: We studied 1534 patients sequentially referred to our center from 2007 to 2016. Fasting serum total 25(OH) vitamin D, plasma cholesterol, triglyceride, HDLC, LDLC, and homocysteine were measured. Stepwise regression models were used with total cholesterol, triglyceride, HDLC, LDLC, and homocysteine as dependent variables and explanatory variables age, race, gender, body mass index (BMI), and serum vitamin D levels. Relationships between quintiles of serum vitamin D and triglycerides, HDLC, LDLC, and homocysteine were assessed after covariance adjusting for age, race, gender, and BMI. Results: Fasting serum vitamin D was positively correlated with age, HDLC, and White race, and was inversely correlated with BMI, total and LDL cholesterol, triglyceride, and fasting serum homocysteine (P ≤ 0.0001 for all). Serum vitamin D was a significant independent inverse explanatory variable for total cholesterol, triglyceride, and LDL cholesterol, and accounted for the largest amount of variance in serum total cholesterol (partial R2 =3.6%), triglyceride (partial R2 =3.1%), and LDLC (partial R2 =2.9%) (P < 0.0001 for all). Serum vitamin D was a significant positive explanatory variable for HDLC (partial R2 = 1.4%, P < 0.0001), and a significant inverse explanatory variable for homocysteine (partial R2 = 6.0–12.6%). Conclusions: In hyperlipidemic patients, serum vitamin D was a significant independent inverse determinant of total cholesterol, LDLC, triglyceride, and homocysteine, and a significant

  15. Emerging therapies for raising high-density lipoprotein cholesterol (HDL-C) and augmenting HDL particle functionality.

    PubMed

    Barylski, Marcin; Toth, Peter P; Nikolic, Dragana; Banach, Maciej; Rizzo, Manfredi; Montalto, Giuseppe

    2014-06-01

    High-density lipoprotein (HDL) particles are highly complex polymolecular aggregates capable of performing a remarkable range of atheroprotective functions. Considerable research is being performed throughout the world to develop novel pharmacologic approaches to: (1) promote apoprotein A-I and HDL particle biosynthesis; (2) augment capacity for reverse cholesterol transport so as to reduce risk for the development and progression of atherosclerotic disease; and (3) modulate the functionality of HDL particles in order to increase their capacity to antagonize oxidation, inflammation, thrombosis, endothelial dysfunction, insulin resistance, and other processes that participate in arterial wall injury. HDL metabolism and the molecular constitution of HDL particles are highly complex and can change in response to both acute and chronic alterations in the metabolic milieu. To date, some of these interventions have been shown to positively impact rates of coronary artery disease progression. However, none of them have as yet been shown to significantly reduce risk for cardiovascular events. In the next 3-5 years a variety of pharmacologic interventions for modulating HDL metabolism and functionality will be tested in large, randomized, prospective outcomes trials. It is hoped that one or more of these therapeutic approaches will result in the ability to further reduce risk for cardiovascular events once low-density lipoprotein cholesterol and non-HDL-cholesterol targets have been attained. PMID:24840270

  16. Effect of apolipoprotein E-free high density lipoproteins on cholesterol metabolism in cultured pig hepatocytes

    SciTech Connect

    Bachorik, P.S.; Virgil, D.G.; Kwiterovich, P.O. Jr.

    1987-10-05

    We studied cholesterol synthesis from (/sup 14/C)acetate, cholesterol esterification from (/sup 14/C)oleate, and cellular cholesterol and cholesteryl ester levels after incubating cells with apoE-free high density lipoproteins (HDL) or low density lipoproteins (LDL). LDL suppressed synthesis by up to 60%, stimulated esterification by up to 280%, and increased cell cholesteryl ester content about 4-fold. Esterification increased within 2 h, but synthesis was not suppressed until after 6 h. ApoE-free HDL suppressed esterification by about 50% within 2 h. Cholesterol synthesis was changed very little within 6 h, unless esterification was maximally suppressed; synthesis was then stimulated about 4-fold. HDL lowered cellular unesterified cholesterol by 13-20% within 2 h and promoted the removal of newly synthesized cholesterol and cholesteryl esters. These changes were transient; by 24 h, both esterification and cellular unesterified cholesterol returned to control levels, and cholesteryl esters increased 2-3-fold. HDL core lipid was taken up selectively from /sup 125/I-labeled (/sup 3/H)cholesteryl ester- and ether-labeled HDL. LDL core lipid uptake was proportional to LDL apoprotein uptake. The findings suggest that 1) the cells respond initially to HDL or LDL with changes in esterification, and 2) HDL mediates both the removal of free cholesterol from the cell and the delivery of HDL cholesteryl esters to the cell.

  17. Cholesterol-Dependent Anaplasma phagocytophilum Exploits the Low-Density Lipoprotein Uptake Pathway

    PubMed Central

    Xiong, Qingming; Lin, Mingqun; Rikihisa, Yasuko

    2009-01-01

    In eukaryotes, intracellular cholesterol homeostasis and trafficking are tightly regulated. Certain bacteria, such as Anaplasma phagocytophilum, also require cholesterol; it is unknown, however, how this cholesterol-dependent obligatory intracellular bacterium of granulocytes interacts with the host cell cholesterol regulatory pathway to acquire cholesterol. Here, we report that total host cell cholesterol increased >2-fold during A. phagocytophilum infection in a human promyelocytic leukemia cell line. Cellular free cholesterol was enriched in A. phagocytophilum inclusions as detected by filipin staining. We determined that A. phagocytophilum requires cholesterol derived from low-density lipoprotein (LDL), because its replication was significantly inhibited by depleting the growth medium of cholesterol-containing lipoproteins, by blocking LDL uptake with a monoclonal antibody against LDL receptor (LDLR), or by treating the host cells with inhibitors that block LDL-derived cholesterol egress from late endosomes or lysosomes. However, de novo cholesterol biosynthesis is not required, since inhibition of the biosynthesis pathway did not inhibit A. phagocytophilum infection. The uptake of fluorescence-labeled LDL was enhanced in infected cells, and LDLR expression was up-regulated at both the mRNA and protein levels. A. phagocytophilum infection stabilized LDLR mRNA through the 3′ UTR region, but not through activation of the sterol regulatory element binding proteins. Extracellular signal–regulated kinase (ERK) was up-regulated by A. phagocytophilum infection, and inhibition of its upstream kinase, MEK, by a specific inhibitor or siRNA knockdown, reduced A. phagocytophilum infection. Up-regulation of LDLR mRNA by A. phagocytophilum was also inhibited by the MEK inhibitor; however, it was unclear whether ERK activation is required for LDLR mRNA up-regulation by A. phagocytophilum. These data reveal that A. phagocytophilum exploits the host LDL uptake pathway and

  18. Membrane Cholesterol Modulates LOX-1 Shedding in Endothelial Cells.

    PubMed

    Gioia, Magda; Vindigni, Giulia; Testa, Barbara; Raniolo, Sofia; Fasciglione, Giovanni Francesco; Coletta, Massimiliano; Biocca, Silvia

    2015-01-01

    The lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a scavenger receptor responsible for ox-LDL recognition, binding and internalization, which is up-regulated during atherogenesis. Its activation triggers endothelium dysfunction and induces inflammation. A soluble form of LOX-1 has been identified in the human blood and its presence considered a biomarker of cardiovascular diseases. We recently showed that cholesterol-lowering drugs inhibit ox-LDL binding and internalization, rescuing the ox-LDL induced apoptotic phenotype in primary endothelial cells. Here we have investigated the molecular bases of human LOX-1 shedding by metalloproteinases and the role of cell membrane cholesterol on the regulation of this event by modulating its level with MβCD and statins. We report that membrane cholesterol affects the release of different forms of LOX-1 in cells transiently and stably expressing human LOX-1 and in a human endothelial cell line (EA.hy926). In particular, our data show that i) cholesterol depletion triggers the release of LOX-1 in exosomes as a full-length transmembrane isoform and as a truncated ectodomain soluble fragment (sLOX-1); ii) endothelial cells secrete a soluble metalloproteinase which induces LOX-1 ectodomain shedding and iii) long term statins treatment enhances sLOX-1 proteolytic shedding. PMID:26495844

  19. Membrane Cholesterol Modulates LOX-1 Shedding in Endothelial Cells

    PubMed Central

    Testa, Barbara; Raniolo, Sofia; Fasciglione, Giovanni Francesco; Coletta, Massimiliano; Biocca, Silvia

    2015-01-01

    The lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a scavenger receptor responsible for ox-LDL recognition, binding and internalization, which is up-regulated during atherogenesis. Its activation triggers endothelium dysfunction and induces inflammation. A soluble form of LOX-1 has been identified in the human blood and its presence considered a biomarker of cardiovascular diseases. We recently showed that cholesterol-lowering drugs inhibit ox-LDL binding and internalization, rescuing the ox-LDL induced apoptotic phenotype in primary endothelial cells. Here we have investigated the molecular bases of human LOX-1 shedding by metalloproteinases and the role of cell membrane cholesterol on the regulation of this event by modulating its level with MβCD and statins. We report that membrane cholesterol affects the release of different forms of LOX-1 in cells transiently and stably expressing human LOX-1 and in a human endothelial cell line (EA.hy926). In particular, our data show that i) cholesterol depletion triggers the release of LOX-1 in exosomes as a full-length transmembrane isoform and as a truncated ectodomain soluble fragment (sLOX-1); ii) endothelial cells secrete a soluble metalloproteinase which induces LOX-1 ectodomain shedding and iii) long term statins treatment enhances sLOX-1 proteolytic shedding. PMID:26495844

  20. Modulation of PICALM Levels Perturbs Cellular Cholesterol Homeostasis.

    PubMed

    Mercer, Jacob L; Argus, Joseph P; Crabtree, Donna M; Keenan, Melissa M; Wilks, Moses Q; Chi, Jen-Tsan Ashley; Bensinger, Steven J; Lavau, Catherine P; Wechsler, Daniel S

    2015-01-01

    PICALM (Phosphatidyl Inositol Clathrin Assembly Lymphoid Myeloid protein) is a ubiquitously expressed protein that plays a role in clathrin-mediated endocytosis. PICALM also affects the internalization and trafficking of SNAREs and modulates macroautophagy. Chromosomal translocations that result in the fusion of PICALM to heterologous proteins cause leukemias, and genome-wide association studies have linked PICALM Single Nucleotide Polymorphisms (SNPs) to Alzheimer's disease. To obtain insight into the biological role of PICALM, we performed gene expression studies of PICALM-deficient and PICALM-expressing cells. Pathway analysis demonstrated that PICALM expression influences the expression of genes that encode proteins involved in cholesterol biosynthesis and lipoprotein uptake. Gas Chromatography-Mass Spectrometry (GC-MS) studies indicated that loss of PICALM increases cellular cholesterol pool size. Isotopic labeling studies revealed that loss of PICALM alters increased net scavenging of cholesterol. Flow cytometry analyses confirmed that internalization of the LDL receptor is enhanced in PICALM-deficient cells as a result of higher levels of LDLR expression. These findings suggest that PICALM is required for cellular cholesterol homeostasis and point to a novel mechanism by which PICALM alterations may contribute to disease. PMID:26075887

  1. Lower Low-Density Lipoprotein Cholesterol Levels Are Associated with Severe Dengue Outcome.

    PubMed

    Biswas, Hope H; Gordon, Aubree; Nuñez, Andrea; Perez, Maria Angeles; Balmaseda, Angel; Harris, Eva

    2015-01-01

    Dengue virus (DENV) is a flavivirus of worldwide importance, with approximately 4 billion people across 128 countries at risk of infection, and up to 390 million infections and 96 million clinically apparent cases estimated annually. Previous in vitro studies have shown that lipids and lipoproteins play a role in modifying virus infectivity. However, the relationship between development of severe dengue and total cholesterol, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), respectively, is unclear. We analyzed data from 789 laboratory-confirmed dengue cases and 447 other febrile illnesses (OFI) in a prospective pediatric hospital-based study in Managua, Nicaragua between August 2005 and January 2013, using three different classifications of dengue severity: World Health Organization (WHO) 1997, WHO 2009, and standardized intervention categories. Total serum cholesterol and LDL-C levels decreased over the course of illness and were generally lower with increasing dengue severity, regardless of classification scheme. Greater decreases in LDL-C than HDL-C were observed among dengue-positive patients compared to patients with OFI and among severe dengue compared to mild dengue cases. Furthermore, daily cholesterol levels declined with daily albumin blood levels. To examine the effect of cholesterol at presentation on subsequent risk of development of severe dengue, relative risks and 95% confidence intervals were calculated using multivariable modified Poisson models. We found that lower total serum cholesterol and LDL-C levels at presentation were associated with subsequent risk of developing dengue hemorrhagic fever/dengue shock syndrome using the WHO 1997 dengue severity classification, and thus that the reduction in LDL-C is likely driving the decreases observed in total serum cholesterol levels among dengue-positive patients. Our results suggest that cholesterol blood levels are important correlates of dengue

  2. Effects of intensive atorvastatin and rosuvastatin treatment on apolipoprotein B-48 and remnant lipoprotein cholesterol levels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Atorvastatin and rosuvastatin at maximal doses are both highly effective in lowering low-density lipoprotein cholesterol (LDL-C) and triglyceride (TG) levels. Rosuvastatin has been shown to be more effective than atorvastatin in lowering LDL-C, small dense LDL-C and in raising high-density lipoprote...

  3. Glycated albumin and direct low density lipoprotein cholesterol levels in type 2 diabetes mellitus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diabetes mellitus is a major risk factor for coronary heart disease (CHD), renal failure, retinopathy, and neuropathy. Lowering glycosylated hemoglobin (HbA1c) as well as low-density lipoprotein-cholesterol (LDL-C) has been associated with a decreased risk of these complications. We evaluated the ut...

  4. Direct Low Density Lipoprotein Cholesterol and Glycated Albumin Levels in Type 2 Diabetes Mellitus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diabetes mellitus is a major risk factor for coronary heart disease (CHD), renal failure, retinopathy, and neuropathy. Lowering glycosylated hemoglobin (HbA1c) as well as low-density lipoprotein-cholesterol (LDL-C) have been associated with a decreased risk of these complications. The aim in this st...

  5. Triglyceride to high density lipoprotein cholesterol ratio, total cholesterol to high density lipoprotein cholesterol ratio and low ankle brachial index in an elderly population.

    PubMed

    Zhan, Yiqiang; Yu, Jinming; Ding, Rongjing; Sun, Yihong; Hu, Dayi

    2014-05-01

    Hintergrund: Der Zusammenhang zwischen den Quotienten aus Triglycerid (TG) und High-density-lipoprotein-cholesterin (HDL‑C) sowie Gesamtcholesterin (TC) und HDL‑C und dem Knöchel-Arm-Index (ABI) wurde selten untersucht. Patienten und Methoden: Insgesamt 2.982 Teinehmer, die über 60 Jahre alt waren, wurden für die bevölkerungsbasierte Querschnittstudie rekrutiert. TG, TC, HDL‑C, und low-density Lipoprotein Cholesterol (LDL-C) wurden bei allen Teilnehmern getestet. Ein niedriger ABI wurde als ABI ≤ 0.9 definiert. Multiple Regressionsmodelle wurden für die Untersuchung der Assoziation zwischen TG/HDL‑C Ratio und TC/HDL‑C Ratio und niedrigem ABI angewendet. Ergebnisse: Die TG/HDL‑C Ratios für ABI > 0.9 und ABI ≤ 0.9 waren 1.28 ± 1.20 und 1.48 ± 1.13 (P < 0.0001), während die TC/HDL‑C Ratios 3.96 ± 1.09 bzw. 4.32 ± 1.15 (P < 0.0001) waren. Nach der Angleichung von Alter, Geschlecht, Body-Mass-Index, Fettleibigkeit, Alkoholkonsum, köperliche Aktivität, Hypertonie, Diabetes, Einnahme von lipidsenkenden Medikamenten, und Herz-Kreislauf-Erkrankungen waren die Odds Ratios (OR) mit 95 % Konfidenzintervall (KI) bei dem niedrigen ABI und TG/HDL‑C Quotient 1,10 (0,96 - 1,26) und 1,34 (1,14 - 1,59) für TC/HDL‑C in der Nichtrauchergruppe. Wenn das TC weiter angeglichen wurde, waren die ORs (95 % CIs) 1.40 (0.79, 2.52) und 1.53 (1.21, 1.93) für die TG/HDL‑C Ratio und TC/HDL‑C Ratio. Nichtlineare Zusammenhänge wurden zwischen der TG/HDL‑C Ratio und TC/HDL‑C Ratio und dem niedrigen ABI in der Raucher- und Nichtrauchergruppe entdeckt. Schlussfolgerungen: Die TC/HDL‑C Ratio war signifikant mit einem niedrigen ABI in der Nichtrauchergruppe verbunden und die Assoziation war unabhängig von TC, TG, HDL‑C und LDL-C. TC/HDL‑C könnte als potentieller Biomarker für die frühe periphere arterielle Verschlusskrankheit beim Screening berücksichtigt werden.

  6. Practical technique to quantify small, dense low-density lipoprotein cholesterol using dynamic light scattering

    NASA Astrophysics Data System (ADS)

    Trirongjitmoah, Suchin; Iinaga, Kazuya; Sakurai, Toshihiro; Chiba, Hitoshi; Sriyudthsak, Mana; Shimizu, Koichi

    2016-04-01

    Quantification of small, dense low-density lipoprotein (sdLDL) cholesterol is clinically significant. We propose a practical technique to estimate the amount of sdLDL cholesterol using dynamic light scattering (DLS). An analytical solution in a closed form has newly been obtained to estimate the weight fraction of one species of scatterers in the DLS measurement of two species of scatterers. Using this solution, we can quantify the sdLDL cholesterol amount from the amounts of the low-density lipoprotein cholesterol and the high-density lipoprotein (HDL) cholesterol, which are commonly obtained through clinical tests. The accuracy of the proposed technique was confirmed experimentally using latex spheres with known size distributions. The applicability of the proposed technique was examined using samples of human blood serum. The possibility of estimating the sdLDL amount using the HDL data was demonstrated. These results suggest that the quantitative estimation of sdLDL amounts using DLS is feasible for point-of-care testing in clinical practice.

  7. Effect of Dietary Fiber Intake on Lipoprotein Cholesterol Levels Independent of Estradiol in Healthy Premenopausal Women

    PubMed Central

    Mumford, Sunni L.; Schisterman, Enrique F.; Siega-Riz, Anna Maria; Gaskins, Audrey J.; Wactawski-Wende, Jean; VanderWeele, Tyler J.

    2011-01-01

    High-fiber diets are associated with improved lipid profiles. However, pre- and postmenopausal women respond differently to fiber intake, suggesting that endogenous estradiol mediates the effect. The authors' objective was to determine the direct effect of fiber intake on lipoprotein cholesterol levels independent of estradiol among premenopausal women. The BioCycle Study, a prospective cohort study conducted at the State University of New York at Buffalo from 2005 to 2007, followed 259 healthy women for up to 2 complete menstrual cycles. Serum lipoprotein and hormone levels were measured at 16 visits timed using fertility monitors. Fiber intake was assessed by 8 24-hour recalls. Marginal structural models with inverse probability weights for both lipoprotein and estradiol levels were used to estimate controlled direct effects of the highest category of fiber intake (≥22 g/day vs. <22 g/day) while accounting for age, body mass index, total energy, vitamin E intake, physical activity, luteinizing hormone, follicle-stimulating hormone, and progesterone. Reductions were observed in total and low density lipoprotein cholesterol in women with higher fiber intakes. Direct effects were greater than total effects. These analyses suggested that estradiol mediates at least part of the association between fiber and cholesterol among premenopausal women. More research is needed to elucidate the biologic mechanisms driving these associations. PMID:21148240

  8. Lipoprotein composition and serum cholesterol ester fatty acids in nonwesternized Melanesians.

    PubMed

    Lindeberg, S; Nilsson-Ehle, P; Vessby, B

    1996-02-01

    In this study, the relationships between dietary fat [as measured by serum cholesterol ester fatty acids (CE-FA)], age, smoking, body mass index, and serum lipids were analyzed in 151 subsistence horticulturalists, aged 20-86 yr, from Kitava, Trobriand Islands, Papua New Guinea. Their diet consists of tubers, fruit, coconut, fish, and vegetables with a negligible influence of western food and alcohol. Total fat intake is low [21% of energy (en%)], while saturated fat intake from coconuts is high (17 en%, mainly lauric and myristic acid). In multivariate analysis, 11-43% of the variation of the serum lipoprotein composition was explained by CE-FA, age, and smoking habits. The proportion of CE20:5n-3 explained much of the variation of triglycerides (TG, negative relation) and high density lipoprotein-cholesterol (HDL-C, positive) in both sexes and serum apolipoprotein A1 (ApoA1, positive) in the males. CE16:0 was positively related to TG and negatively related to HDL-C and ApoA1 in both sexes, and in males it related negatively to total cholesterol (TC) and low density lipoprotein-cholesterol (LDL-C). In males, negative relationships were present between CE18:2n-6 and TC and between CE14:0 and serum lipoprotein(a). Smoking was independently associated with lower ApoA1 in both sexes and with lower HDL-C and higher TG, TC, LDL-C, and apolipoprotein B in males. In conclusion, marine n-3 fatty acids and linoleic acid showed the same potentially beneficial relationships with lipoproteins and apolipoproteins as in western populations. The relations of palmitic acid to serum lipids may be explained in terms of endogenous fat synthesis at a low-fat intake, rather than reflecting its relative intake.

  9. High-Density Lipoprotein-Mediated Transcellular Cholesterol Transport in Mouse Aortic Endothelial Cells

    PubMed Central

    Miao, LiXia; Okoro, Emmanuel U.; Cao, ZhiJan; Yang, Hong; Motley-Johnson, Evangeline; Guo, Zhongmao

    2015-01-01

    Accumulation of unesterified cholesterol-rich lipid vesicles in the subendothelial space contributes to atherogenesis. Transport of cholesterol from the subendothelial intima back to the circulating blood inhibits atherosclerosis development; however, the mechanism for this process has not been fully defined. Using cultured mouse aortic endothelial cells (MAECs), we observed that unesterified cholesterol can be transported across the endothelial cell monolayer from the basolateral to the apical compartment. Administration of high-density lipoprotein (HDL) or apolipoprotein AI (apoAI) to the apical compartment enhanced transendothelial cholesterol transport in a concentration-dependent manner. Knockdown of ATP-binding cassette transporter G1 (ABCG1) or scavenger receptor class B type I (SR-B1), or inhibition of SR-B1 diminished HDL-induced transendothelial cholesterol transport; while knockdown of ABCA1 reduced apoAI-mediated cholesterol transport. HDL enhanced phosphorylation of phosphatidylinositol 3-kinase (PI3K) and Akt in MAECs. However, inhibition PI3K or Akt did not reduce HDL-induced transendothelial cholesterol transport. These results suggest that HDL enhances transendothelial cholesterol transport by activation of a mechanism involving ABCA1, ABCA1 and SR-B1 but not involving PI3K and Akt. PMID:26255968

  10. Effect of cigarette smoke and dietary cholesterol on plasma lipoprotein composition

    SciTech Connect

    Hojnacki, J.L.; Mulligan, J.J.; Cluette, J.E.; Kew, R.R.; Stack, D.J.; Huber, G.L.

    1981-01-01

    Pigeons were assigned to four treatment groups: 1) Controls fed a chow diet ad libitum and retained in their cages; 2) Sham pigeons fed a cholesterol-saturated fat diet and exposed to fresh air by the Lorillard smoking machine; 3) Low nicotine-low carbon monoxide (LoLo) animals also fed the cholesterol diet and exposed to low concentrations of cigarette smoke; and 4) High nicotine-high carbon monoxide (HiHi) birds fed the cholesterol diet and subjected to high concentrations of inhalants. Plasma very low density (VLDL), low density (LDL), and high density (HDL) lipoproteins were isolated by density gradient ultracentrifugation. Smoke-related differences appeared in HiHi HDL which contained relatively more free and esterified cholesterol and total lipid, but less total protein than HDL from Sham-smoked pigeons. VLDL from birds exposed to cigarette smoke (LoLo and HiHi) contained relatively more total lipid, but less total protein than VLDL from Sham pigeons. Inhalation smoke produced a marked depression in the HDL2/HDL3 ratio resulting from an increased proportion of the HDL3 subfraction relative to HDL2. Pigeons fed the cholesterol-saturated fat diet circulated HDL with greater free and esterified cholesterol mass than Controls. Diet also altered the type of cholesteryl ester present in HDL with cholesteryl linoleate representing the predominant form in Control pigeons and cholesteryl oleate in cholesterol-fed birds. These results demonstrate that cigarette smoking can mediate alterations in lipoprotein composition independent of changes induced by dietary cholesterol and saturated fat.

  11. [Cholesterol bound to high density lipoproteins: critical review of the methods of analysis and personal data].

    PubMed

    Orso Giacone, G

    1982-01-01

    It is widely known that atherosclerosis through its complication, i.e. heart and brain infarction, is at the present the main cause of death. The atherosclerotic process has been shown in correlation with hyperlipemia especially as far as the plasma lipoprotein cholesterol level is concerned. A preminent role in removing cholesterol from tissues and arterial walls then in preventing atherosclerosis is played by a specific class of plasma lipoproteins, the high density lipoproteins (HDL). Since the HDL-colesterol level seems to have an inverse correlation with the atherosclerotic disease it is of primary importance to define a reliable and reproducible technique to measure it. One of the aims of this paper was to examine the different methods now available for such a determination. This analysis has underlined the discrepancy among the reference values reported in the literature. However, all the authors agree that only the simultaneous measurement of total and HDL-colesterol levels is of prognostic value. Personal studies are here reported on the relationship between total and HDL-colesterol levels and risk factor of cardiovascular diseases. The two mentioned laboratory analyses have been performed on blood samples from 250 between male and female human subjects of different age. The obtained results show that the highest HDL-colesterol concentrations determined by a lipoprotein precipitation procedure with dextran sulphate, are typical in the first ten years of life both in male and in female, while the lowest levels of plasma HDL-cholesterol have been evintiated during the fifth decade of life, when the total cholesterol and the risk of cardiovascular complications rich the highest values. In a following set of investigations, the already examined blood parameters together with the risk factor values have been examined in two groups of subjects, the first one represented by adult healthy persons the second one by patients of similar age from a cardiovascular

  12. Oxidation of cholesterol does not alter significantly its uptake into high-density lipoprotein particles.

    PubMed

    Karilainen, Topi; Timr, Štěpán; Vattulainen, Ilpo; Jungwirth, Pavel

    2015-04-01

    Using replica exchange umbrella sampling we calculated free energy profiles for uptake of cholesterol and one of its oxysterols (7-ketocholesterol) from an aqueous solution into a high-density lipoprotein particle. These atomistic molecular dynamics simulations show that both sterols are readily taken up from the aqueous solution with comparable free energy minima at the surface of the particle of -17 kcal/mol for cholesterol and -14 kcal/mol for 7-ketocholesterol. Moreover, given its preferred position at the particle surface, 7-ketocholesterol is expected to be able to participate directly in biological signaling processes.

  13. [Cholesterol bound to high density lipoproteins: critical review of the methods of analysis and personal data].

    PubMed

    Orso Giacone, G

    1982-01-01

    It is widely known that atherosclerosis through its complication, i.e. heart and brain infarction, is at the present the main cause of death. The atherosclerotic process has been shown in correlation with hyperlipemia especially as far as the plasma lipoprotein cholesterol level is concerned. A preminent role in removing cholesterol from tissues and arterial walls then in preventing atherosclerosis is played by a specific class of plasma lipoproteins, the high density lipoproteins (HDL). Since the HDL-colesterol level seems to have an inverse correlation with the atherosclerotic disease it is of primary importance to define a reliable and reproducible technique to measure it. One of the aims of this paper was to examine the different methods now available for such a determination. This analysis has underlined the discrepancy among the reference values reported in the literature. However, all the authors agree that only the simultaneous measurement of total and HDL-colesterol levels is of prognostic value. Personal studies are here reported on the relationship between total and HDL-colesterol levels and risk factor of cardiovascular diseases. The two mentioned laboratory analyses have been performed on blood samples from 250 between male and female human subjects of different age. The obtained results show that the highest HDL-colesterol concentrations determined by a lipoprotein precipitation procedure with dextran sulphate, are typical in the first ten years of life both in male and in female, while the lowest levels of plasma HDL-cholesterol have been evintiated during the fifth decade of life, when the total cholesterol and the risk of cardiovascular complications rich the highest values. In a following set of investigations, the already examined blood parameters together with the risk factor values have been examined in two groups of subjects, the first one represented by adult healthy persons the second one by patients of similar age from a cardiovascular

  14. Drugs targeting high-density lipoprotein cholesterol for coronary artery disease management.

    PubMed

    Katz, Pamela M; Leiter, Lawrence A

    2012-01-01

    Many patients remain at high risk for future cardiovascular events despite levels of low-density lipoprotein cholesterol (LDL-C) at, or below, target while taking statin therapy. Much effort is therefore being focused on strategies to reduce this residual risk. High-density lipoprotein cholesterol (HDL-C) is a strong, independent, inverse predictor of coronary heart disease risk and is therefore an attractive therapeutic target. Currently available agents that raise HDL-C have only modest effects and there is limited evidence of additional cardiovascular risk reduction on top of background statin therapy associated with their use. It was hoped that the use of cholesteryl ester transfer protein (CETP) inhibitors would provide additional benefit, but the results of clinical outcome studies to date have been disappointing. The results of ongoing trials with other CETP inhibitors that raise HDL-C to a greater degree and also lower LDL-C, as well as with other emerging therapies are awaited.

  15. Genomic determinants of triglyceride and cholesterol distribution into lipoprotein fractions in the rat.

    PubMed

    Hodúlová, Miloslava; Šedová, Lucie; Křenová, Drahomíra; Liška, František; Krupková, Michaela; Kazdová, Ludmila; Tremblay, Johanne; Hamet, Pavel; Křen, Vladimír; Šeda, Ondřej

    2014-01-01

    The plasma profile of major lipoprotein classes and its subdivision into particular fractions plays a crucial role in the pathogenesis of atherosclerosis and is a major predictor of coronary artery disease. Our aim was to identify genomic determinants of triglyceride and cholesterol distribution into lipoprotein fractions and lipoprotein particle sizes in the recombinant inbred rat set PXO, in which alleles of two rat models of the metabolic syndrome (SHR and PD inbred strains) segregate together with those from Brown Norway rat strain. Adult male rats of 15 PXO strains (n = 8-13/strain) and two progenitor strains SHR-Lx (n = 13) and BXH2/Cub (n = 18) were subjected to one-week of high-sucrose diet feeding. We performed association analyses of triglyceride (TG) and cholesterol (C) concentrations in 20 lipoprotein fractions and the size of major classes of lipoprotein particles utilizing 704 polymorphic microsatellite markers, the genome-wide significance was validated by 2,000 permutations per trait. Subsequent in silico focusing of the identified quantitative trait loci was completed using a map of over 20,000 single nucleotide polymorphisms. In most of the phenotypes we identified substantial gradient among the strains (e.g. VLDL-TG from 5.6 to 66.7 mg/dl). We have identified 14 loci (encompassing 1 to 65 genes) on rat chromosomes 3, 4, 7, 8, 11 and 12 showing suggestive or significant association to one or more of the studied traits. PXO strains carrying the SHR allele displayed significantly higher values of the linked traits except for LDL-TG and adiposity index. Cholesterol concentrations in large, medium and very small LDL particles were significantly associated to a haplotype block spanning part of a single gene, low density lipoprotein receptor-related protein 1B (Lrp1b). Using genome-wide association we have identified new genetic determinants of triglyceride and cholesterol distribution into lipoprotein fractions in the recombinant inbred

  16. Genomic Determinants of Triglyceride and Cholesterol Distribution into Lipoprotein Fractions in the Rat

    PubMed Central

    Hodúlová, Miloslava; Šedová, Lucie; Křenová, Drahomíra; Liška, František; Krupková, Michaela; Kazdová, Ludmila; Tremblay, Johanne; Hamet, Pavel; Křen, Vladimír; Šeda, Ondřej

    2014-01-01

    The plasma profile of major lipoprotein classes and its subdivision into particular fractions plays a crucial role in the pathogenesis of atherosclerosis and is a major predictor of coronary artery disease. Our aim was to identify genomic determinants of triglyceride and cholesterol distribution into lipoprotein fractions and lipoprotein particle sizes in the recombinant inbred rat set PXO, in which alleles of two rat models of the metabolic syndrome (SHR and PD inbred strains) segregate together with those from Brown Norway rat strain. Adult male rats of 15 PXO strains (n = 8–13/strain) and two progenitor strains SHR-Lx (n = 13) and BXH2/Cub (n = 18) were subjected to one-week of high-sucrose diet feeding. We performed association analyses of triglyceride (TG) and cholesterol (C) concentrations in 20 lipoprotein fractions and the size of major classes of lipoprotein particles utilizing 704 polymorphic microsatellite markers, the genome-wide significance was validated by 2,000 permutations per trait. Subsequent in silico focusing of the identified quantitative trait loci was completed using a map of over 20,000 single nucleotide polymorphisms. In most of the phenotypes we identified substantial gradient among the strains (e.g. VLDL-TG from 5.6 to 66.7 mg/dl). We have identified 14 loci (encompassing 1 to 65 genes) on rat chromosomes 3, 4, 7, 8, 11 and 12 showing suggestive or significant association to one or more of the studied traits. PXO strains carrying the SHR allele displayed significantly higher values of the linked traits except for LDL-TG and adiposity index. Cholesterol concentrations in large, medium and very small LDL particles were significantly associated to a haplotype block spanning part of a single gene, low density lipoprotein receptor-related protein 1B (Lrp1b). Using genome-wide association we have identified new genetic determinants of triglyceride and cholesterol distribution into lipoprotein fractions in the recombinant inbred

  17. The ATP-binding Cassette Transporter-2 (ABCA2) Regulates Cholesterol Homeostasis and Low-density Lipoprotein Receptor Metabolism in N2a Neuroblastoma Cells

    PubMed Central

    Davis, Warren

    2011-01-01

    The ATP-binding cassette transporter-2 (ABCA2) has been identified as a possible regulator of lipid metabolism. ABCA2 is most highly expressed in the brain but its effects on cholesterol homeostasis in neuronal-type cells have not been characterized. It is important to study the role of ABCA2 in regulating cholesterol homeostasis in neuronal-type cells because ABCA2 has been identified as a possible genetic risk factor for Alzheimer’s disease. In this study, the effects of ABCA2 expression on cholesterol homeostasis were examined in mouse N2a neuroblastoma cells. ABCA2 reduced total, free- and esterified cholesterol levels as well as membrane cholesterol but did not perturb cholesterol distribution in organelle or lipid raft compartments. ABCA2 did not modulate de novo cholesterol biosynthesis from acetate. Cholesterol trafficking to the plasma membrane was not affected by ABCA2 but efflux to the physiological acceptor ApoE3 and mobilization of plasma membrane cholesterol to the endoplasmic reticulum for esterification were reduced by ABCA2. ABCA2 reduced esterification of serum and low-density lipoprotein-derived cholesterol but not 25-hydroxycholesterol. ABCA2 decreased low-density lipoprotein receptor (LDLR) mRNA and protein levels and increased its turnover rate. The surface expression of LDLR as well as the uptake of fluroresecent DiI-LDL was also reduced by ABCA2. Reduction of endogenous ABCA2 expression by RNAi treatment of N2a cells and rat primary cortical neurons produced the opposite effects of over-expression of ABCA2, increasing LDLR protein levels. This report identifies ABCA2 as a key regulator of cholesterol homeostasis and LDLR metabolism in neuronal cells. PMID:21810484

  18. 'Trig-onometry': non-high-density lipoprotein cholesterol as a therapeutic target in dyslipidaemia.

    PubMed

    Jacobson, T A

    2011-01-01

    Targeting elevations in low-density lipoprotein cholesterol (LDL-C) remains the cornerstone of cardiovascular prevention. However, this fraction does not adequately capture elevated triglyceride-rich lipoproteins (TRLs; e.g. intermediate-density lipoprotein, very low density lipoprotein) in certain patients with metabolic syndrome or diabetic dyslipidaemia. Many such individuals have residual cardiovascular risk that might be lipid/lipoprotein related despite therapy with first-line agents (statins). Epidemiological evidence encompassing > 100,000 persons supports the contention that non-high-density lipoprotein cholesterol (non-HDL-C) is a superior risk factor vs. LDL-C for incident coronary heart disease (CHD) in certain patient populations. In studies with clinical end-points evaluated in the current article, a 1:1 to 1:3 relationship was observed between reductions in non-HDL-C and in the relative risk of CHD after long-term treatment with statins, niacin (nicotinic acid) and fibric-acid derivatives (fibrates); this relationship increased to 1:5 to 1:10 in smaller subgroups of patients with elevated triglycerides and low HDL-C levels. Treatment with statin-, niacin-, fibrate-, ezetimibe-, and omega 3 fatty acid-containing regimens reduced non-HDL-C by approximately 9-65%. In a range of clinical trials, long-term treatment with these agents also significantly decreased the incidence of clinical/angiographic/imaging efficacy outcome variables. For patients with dyslipidaemia, consensus guidelines have established non-HDL-C treatment targets 30 mg/dl higher than LDL-C goals. Ongoing prospective randomised controlled trials should help to resolve controversies concerning (i) the clinical utility of targeting non-HDL-C in patients with dyslipidaemia; (ii) the most efficacious and well-tolerated therapies to reduce non-HDL-C (e.g. combination regimens); and (iii) associations between such reductions and clinical, angiographic, and/or imaging end-points. PMID:21105969

  19. Current guidelines for high-density lipoprotein cholesterol in therapy and future directions

    PubMed Central

    Subedi, Bishnu H; Joshi, Parag H; Jones, Steven R; Martin, Seth S; Blaha, Michael J; Michos, Erin D

    2014-01-01

    Many studies have suggested that a significant risk factor for atherosclerotic cardiovascular disease (ASCVD) is low high-density lipoprotein cholesterol (HDL-C). Therefore, increasing HDL-C with therapeutic agents has been considered an attractive strategy. In the prestatin era, fibrates and niacin monotherapy, which cause modest increases in HDL-C, reduced ASCVD events. Since their introduction, statins have become the cornerstone of lipoprotein therapy, the benefits of which are primarily attributed to decrease in low-density lipoprotein cholesterol. Findings from several randomized trials involving niacin or cholesteryl ester transfer protein inhibitors have challenged the concept that a quantitative elevation of plasma HDL-C will uniformly translate into ASCVD benefits. Consequently, the HDL, or more correctly, HDL-C hypothesis has become more controversial. There are no clear guidelines thus far for targeting HDL-C or HDL due to lack of solid outcomes data for HDL specific therapies. HDL-C levels are only one marker of HDL out of its several structural or functional properties. Novel approaches are ongoing in developing and assessing agents that closely mimic the structure of natural HDL or replicate its various functions, for example, reverse cholesterol transport, vasodilation, anti-inflammation, or inhibition of platelet aggregation. Potential new approaches like HDL infusions, delipidated HDL, liver X receptor agonists, Apo A-I upregulators, Apo A mimetics, and gene therapy are in early phase trials. This review will outline current therapies and describe future directions for HDL therapeutics. PMID:24748800

  20. Current guidelines for high-density lipoprotein cholesterol in therapy and future directions.

    PubMed

    Subedi, Bishnu H; Joshi, Parag H; Jones, Steven R; Martin, Seth S; Blaha, Michael J; Michos, Erin D

    2014-01-01

    Many studies have suggested that a significant risk factor for atherosclerotic cardiovascular disease (ASCVD) is low high-density lipoprotein cholesterol (HDL-C). Therefore, increasing HDL-C with therapeutic agents has been considered an attractive strategy. In the prestatin era, fibrates and niacin monotherapy, which cause modest increases in HDL-C, reduced ASCVD events. Since their introduction, statins have become the cornerstone of lipoprotein therapy, the benefits of which are primarily attributed to decrease in low-density lipoprotein cholesterol. Findings from several randomized trials involving niacin or cholesteryl ester transfer protein inhibitors have challenged the concept that a quantitative elevation of plasma HDL-C will uniformly translate into ASCVD benefits. Consequently, the HDL, or more correctly, HDL-C hypothesis has become more controversial. There are no clear guidelines thus far for targeting HDL-C or HDL due to lack of solid outcomes data for HDL specific therapies. HDL-C levels are only one marker of HDL out of its several structural or functional properties. Novel approaches are ongoing in developing and assessing agents that closely mimic the structure of natural HDL or replicate its various functions, for example, reverse cholesterol transport, vasodilation, anti-inflammation, or inhibition of platelet aggregation. Potential new approaches like HDL infusions, delipidated HDL, liver X receptor agonists, Apo A-I upregulators, Apo A mimetics, and gene therapy are in early phase trials. This review will outline current therapies and describe future directions for HDL therapeutics.

  1. Non-high density lipoprotein cholesterol versus low density lipoprotein cholesterol as a discriminating factor for myocardial infarction

    PubMed Central

    2012-01-01

    Background Serum total cholesterol (TC) and LDL cholesterol (LDL-C) have been used as major laboratory measures in clinical practice to assess cardiovascular risk in the general population and disease management as well as prognosis in patients. However, some studies have also reported the use of non-HDL cholesterol (non-HDL-C). As non-HDL-C can be calculated by subtracting HDL-C from TC, both of which do not require fasting blood sample in contrast to LDL-C which requires fasting blood sample, we aimed to compare non-HDL-C with LDL-C as a predictor of myocardial infarction (MI). Methods This hospital based cross sectional study was undertaken among 51 cases of MI and equal number of controls. MI was diagnosed based on the clinical history, ECG changes and biochemical parameters. 5 mL of fasting blood sample was collected from each research participant for the analysis of lipid profile. Non-HDL-C was calculated by using the equation; Non-HDL-C = TC – HDL-C. Statistical analysis was performed using SPSS 14.0. Results 42 MI cases were dyslipidemic in contrast to 20 dyslipidemic subjects under control group. The differences in the median values of each lipid parameter were statistically significant between MI cases and controls. The lipid risk factors most strongly associated with MI were HDL-C (OR 5.85, 95% CI 2.41-14.23, P value = 0.000) followed by non-HDL-C (OR 3.77, 95% CI 1.64-8.66, P value = 0.002), LDL-C/HDL-C (OR 3.38, 95% CI 1.44-7.89, P value = 0.005), TC/HDL-C (OR 2.93, 95% CI 1.36-7.56, P value = 0.026), LDL-C (OR 2.70, 95% CI 1.20-6.10, P value = 0.017), TC (OR 2.68, 95% CI 1.04-6.97, P value = 0.042) and Tg (OR 2.54, 95% CI 1.01-6.39, P value = 0.047). Area under the receiver operating curve was greater for non-HDL-C than for LDL-C. Non-HDL-C was also found to be more sensitive and specific than LDL-C for MI. Conclusions HDL-C and non-HDL-C are better discriminating parameters than LDL-C for MI. Thus, we can simply

  2. A plasma lipoprotein containing only apolipoprotein E and with gamma mobility on electrophoresis releases cholesterol from cells.

    PubMed Central

    Huang, Y; von Eckardstein, A; Wu, S; Maeda, N; Assmann, G

    1994-01-01

    Previous studies have identified lipid-poor high density lipoproteins with electrophoretic pre-beta mobility as the initial acceptors of cell-derived cholesterol in human plasma. These lipoproteins contain apolipoprotein A-I (apo A-I) as their sole apolipoprotein. In the present study, incubation of human plasma with [3H]cholesterol-laden skin fibroblasts has led to the identification of another lipoprotein that serves as a potent initial acceptor of cell-derived cholesterol. This lipoprotein, which we term gamma-LpE, exhibits gamma mobility on agarose gel electrophoresis. As determined by nondenaturing PAGE and by electron microscopy, the size of the spherical particle ranges between 12 and 16 nm. SDS/PAGE and subsequent immunoblotting identified apoE as its sole apolipoprotein. Plasma from normal and apoA-I-deficient mice, but not from apoE-deficient mice, released [3H]cholesterol from fibroblasts into a gamma-migrating lipoprotein. Cell culture media from hepatoma cells or mouse peritoneal macrophages, both of which contain apoE of cellular origin, also promoted efflux of [3H]cholesterol from fibroblasts into a gamma-migrating fraction. This was not observed with cell culture medium from fibroblasts alone. In conclusion, our results strongly indicate the presence in human plasma of a lipoprotein containing only apoE, gamma-LpE, which is secreted by peripheral cells and is a potent acceptor of cell-derived cholesterol. Images PMID:8127890

  3. Thinking beyond low-density lipoprotein cholesterol: strategies to further reduce cardiovascular risk.

    PubMed

    Sharma, Rakesh K; Singh, Vibhuti N; Reddy, Hanumanth K

    2009-01-01

    Several large statin trials and meta-analyses have demonstrated a reduction in low-density lipoprotein cholesterol (LDL-C) and cardiovascular morbidity and mortality. Some trials have also highlighted the significance of residual cardiovascular risk after treatment of LDL-C to target levels. This reflects the complex nature of residual cardiovascular risk. This residual risk is partially due to low HDL-C and high triglycerides (TG) despite achievement of LDL goals with statin therapy. The NCEP ATP III guidelines reported that low HDL-C is a significant and an independent risk factor for coronary heart disease (CHD) and is inversely related to CHD. Epidemiologic studies have also shown a similar inverse relationship of HDL-C with CHD. High-density lipoprotein cholesterol (HDL-C) may directly participate in the anti-atherogenic process by promoting efflux of cholesterol of the foam cells of atherogenic lesions. Many studies have demonstrated multiple anti-atherogenic actions of HDL-C and its role in promoting efflux of cholesterol from the foam cells. The residual risk by increased TG with or without low HDL-C can be assessed by calculating non-HDL-C and a reduction in TG results in decreased CHD. PMID:19812691

  4. SR-BI: Linking Cholesterol and Lipoprotein Metabolism with Breast and Prostate Cancer

    PubMed Central

    Gutierrez-Pajares, Jorge L.; Ben Hassen, Céline; Chevalier, Stéphan; Frank, Philippe G.

    2016-01-01

    Studies have demonstrated the significant role of cholesterol and lipoprotein metabolism in the progression of cancer. The SCARB1 gene encodes the scavenger receptor class B type I (SR-BI), which is an 82-kDa glycoprotein with two transmembrane domains separated by a large extracellular loop. SR-BI plays an important role in the regulation of cholesterol exchange between cells and high-density lipoproteins. Accordingly, hepatic SR-BI has been shown to play an essential role in the regulation of the reverse cholesterol transport pathway, which promotes the removal and excretion of excess body cholesterol. In the context of atherosclerosis, SR-BI has been implicated in the regulation of intracellular signaling, lipid accumulation, foam cell formation, and cellular apoptosis. Furthermore, since lipid metabolism is a relevant target for cancer treatment, recent studies have focused on examining the role of SR-BI in this pathology. While signaling pathways have initially been explored in non-tumoral cells, studies with cancer cells have now demonstrated SR-BI's function in tumor progression. In this review, we will discuss the role of SR-BI during tumor development and malignant progression. In addition, we will provide insights into the transcriptional and post-transcriptional regulation of the SCARB1 gene. Overall, studying the role of SR-BI in tumor development and progression should allow us to gain useful information for the development of new therapeutic strategies. PMID:27774064

  5. High density lipoprotein cholesterol as a determinant factor in coronary heart disease in Africans.

    PubMed Central

    Adebonojo, S. A.; Ogunnaike, H. O.

    1989-01-01

    A study of the lipid profile of 200 normal Nigerian subjects (Group A) shows a steady increase in the total cholesterol and triglyceride values with increasing age in both sexes, while the high density lipoprotein (HDL) cholesterol and percent HDL cholesterol values show a steady decrease with increasing age in both sexes. A similar study of 160 patients with high-risk factors (Group B), ie, patients with hypertension, diabetes mellitus, cigarette smokers, and obese patients, shows significantly higher values of mean triglyceride than in the normal subjects (P less than 0.001). The HDL cholesterol and percent HDL cholesterol values are significantly lower in the high risk patients than in the normal subjects (P less than 0.001). A study of the lipid profile of 15 Nigerian patients with coronary heart disease (CHD) (Group C) shows significantly lower in the high-risk patients than in the percent HDL cholesterol than normal subjects (P less than 0.001). These values were also found to be significantly lower in Group C patients than in Group B patients (P less than 0.01). A comparison of the lipid profile of normal Nigerian subjects with those of black Americans shows that the total cholesterol values of normal black Americans are significantly higher than those of normal Nigerians of comparable age and sex (P less than 0.001). Although there is no significant difference in the HDL cholesterol values of both black American and Nigerian males and females, the values of the percent HDL cholesterol of black Americans are significantly lower (P less than 0.01) than those of Nigerians of comparable age and sex.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2746678

  6. A MARCH6 and IDOL E3 Ubiquitin Ligase Circuit Uncouples Cholesterol Synthesis from Lipoprotein Uptake in Hepatocytes

    PubMed Central

    Loregger, Anke; Cook, Emma Claire Laura; Nelson, Jessica Kristin; Moeton, Martina; Sharpe, Laura Jane; Engberg, Susanna; Karimova, Madina; Lambert, Gilles; Brown, Andrew John

    2015-01-01

    Cholesterol synthesis and lipoprotein uptake are tightly coordinated to ensure that the cellular level of cholesterol is adequately maintained. Hepatic dysregulation of these processes is associated with pathological conditions, most notably cardiovascular disease. Using a genetic approach, we have recently identified the E3 ubiquitin ligase MARCH6 as a regulator of cholesterol biosynthesis, owing to its ability to promote degradation of the rate-limiting enzymes 3-hydroxy-3-methyl-glutaryl coenzyme A reductase (HMGCR) and squalene epoxidase (SQLE). Here, we present evidence for MARCH6 playing a multifaceted role in the control of cholesterol homeostasis in hepatocytes. We identify MARCH6 as an endogenous inhibitor of the sterol regulatory element binding protein (SREBP) transcriptional program. Accordingly, loss of MARCH6 increases expression of SREBP-regulated genes involved in cholesterol biosynthesis and lipoprotein uptake. Unexpectedly, this is associated with a decrease in cellular lipoprotein uptake, induced by enhanced lysosomal degradation of the low-density lipoprotein receptor (LDLR). Finally, we provide evidence that induction of the E3 ubiquitin ligase IDOL represents the molecular mechanism underlying this MARCH6-induced phenotype. Our study thus highlights a MARCH6-dependent mechanism to direct cellular cholesterol accretion that relies on uncoupling of cholesterol synthesis from lipoprotein uptake. PMID:26527619

  7. Effects of maximal doses of atorvastatin versus rosuvastatin on small dense low-density lipoprotein cholesterol levels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maximal doses of atorvastatin and rosuvastatin are highly effective in lowering low-density lipoprotein (LDL) cholesterol and triglyceride levels; however, rosuvastatin has been shown to be significantly more effective than atorvastatin in lowering LDL cholesterol and in increasing high-density lipo...

  8. [Lipoprotein metabolic characteristics in the liver and intestinal wall of rabbits after a single exposure to sunflower oil and cholesterol].

    PubMed

    Leskova, G F

    1982-04-01

    Lipoprotein metabolism in the rabbit liver and intestinal wall was studied by an alimentary action on the cholesterol blood content. The data obtained indicated that the diet including cholesterol intensifies the release of chylomicrons into the lymph of the intestinal lymphatic trunk. Single addition of sunflower-seed oil to the diet leads to the increased deposition of high, low and very low density lipoproteins in the intestinal wall. Upon adding cholesterol to the rabbit diet the retention of low and very low density lipids in the intestine is followed by the increased release of high density lipoproteins into the blood of the portal vein. Single addition of sunflower-seed oil stimulates the synthesis of high density lipoproteins by the rabbit liver.

  9. The amount of dietary cholesterol changes the mode of effects of (n-3) polyunsaturated fatty acid on lipoprotein cholesterol in hamsters.

    PubMed

    Lin, Mei-Huei; Lu, Shao-Chun; Huang, Po-Chao; Liu, Young-Chau; Liu, Shyun-Yeu

    2004-01-01

    This study was designed to investigate the effects of the interaction between dietary (n-3) polyunsaturated fatty acids (PUFA) and different dietary cholesterol content on plasma and liver cholesterol in hamsters. Male Syrian hamsters consumed diets containing an incremental increase in dietary cholesterol content (0, 0.025, 0.05, 0.1 and 0.2%, w/w) with either (n-3) PUFA (21 g/100 g fatty acids) or (n-6) PUFA (37.4 g/100 g fatty acids) fat for 6 weeks. In hamsters fed the nonatherogenic diet (0 or 0.025% dietary cholesterol), very low density lipoprotein (VLDL)-cholesterol levels in the (n-3) PUFA group were not significantly different from those in the (n-6) PUFA group, and low density lipoprotein (LDL)-cholesterol levels in the (n-3) PUFA group were significantly lower than those in the (n-6) PUFA group. In contrast, in hamsters fed the atherogenic diet (0.1 or 0.2% dietary cholesterol), VLDL- and LDL-cholesterol levels in the (n-3) PUFA group were significantly higher than those in the (n-6) PUFA group, in a dose-dependent manner. When the hamsters were fed with 0, 0.025, 0.05, 0.1 or 0.2% (w/w) dietary cholesterol, high density lipoprotein (HDL) cholesterol concentration was significantly lower in the (n-3) PUFA group than those in the (n-6) PUFA group. Hepatic cholesteryl esters were significantly lower, while hepatic microsomal acyl-coenzyme A:cholesterol acyltransferase activity and VLDL-cholesteryl esters were significantly higher in hamsters fed (n-3) PUFA with the atherogenic diet (0.1 or 0.2% dietary cholesterol) than in those fed (n-6) PUFA with the atherogenic diet. Our results demonstrate that the amount of dietary cholesterol is an important factor in determining the mode and extent of effects of dietary (n-3) PUFA, especially on VLDL- and LDL-cholesterol levels. When dietary cholesterol intake was above 0.1% (w/w), the plasma cholesterol-lowering effect of (n-3) PUFA disappeared, and instead, it showed a cholesterol-increasing effect. However, the

  10. Distribution of lipoprotein phenotypes, cholesterol, and lipids in inner-city blacks.

    PubMed

    Foster, P; Jackson, M

    1993-03-01

    Lipoprotein phenotypes total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglyceride levels were obtained from blood samples of 189 patients attending the Drew Hamilton Clinic in Central Harlem, New York, between 1987 and 1988. The study population ranged in age from 7 to 88 years; 135 of the patients were females and 54 were males. A difference in distribution of lipoprotein phenotypes was observed compared with the general population of the United States. Sixty-seven percent of blacks in this study were Type IIA compared with an estimated 10% of the general US population. Differences also were observed for blacks versus the general US population for Type IV (24% versus 45%), Type IIB (9% versus 40%), and Type V (0% versus 5%). Types I and III were rare in both groups (0% versus < 1%). The increased frequency of Type IIA among this predominantly black inner-city population may have implications for treatment strategies and prognostic value for predicting the risk of coronary heart disease.

  11. Distribution of lipoprotein phenotypes, cholesterol, and lipids in inner-city blacks.

    PubMed Central

    Foster, P.; Jackson, M.

    1993-01-01

    Lipoprotein phenotypes total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglyceride levels were obtained from blood samples of 189 patients attending the Drew Hamilton Clinic in Central Harlem, New York, between 1987 and 1988. The study population ranged in age from 7 to 88 years; 135 of the patients were females and 54 were males. A difference in distribution of lipoprotein phenotypes was observed compared with the general population of the United States. Sixty-seven percent of blacks in this study were Type IIA compared with an estimated 10% of the general US population. Differences also were observed for blacks versus the general US population for Type IV (24% versus 45%), Type IIB (9% versus 40%), and Type V (0% versus 5%). Types I and III were rare in both groups (0% versus < 1%). The increased frequency of Type IIA among this predominantly black inner-city population may have implications for treatment strategies and prognostic value for predicting the risk of coronary heart disease. PMID:8474135

  12. A Subregion of Reelin Suppresses Lipoprotein-Induced Cholesterol Accumulation in Macrophages

    PubMed Central

    Guo, Zhongmao; Yang, Fang; Smith, Carlie; Yang, Hong

    2015-01-01

    Activation of apolipoprotein E receptor-2 (apoER2) and very low density lipoprotein receptor (VLDLR) inhibits foam cell formation. Reelin is a ligand of these receptors. Here we generated two reelin subregions containing the receptor binding domain with or without its C-terminal region (R5-6C and R5-6, respectively) and studied the impact of these peptides on macrophage cholesterol metabolism. We found that both R5-6C and R5-6 can be secreted by cells. Purified R5-6 protein can bind apoER2 and VLDLR. Overexpression of apoER2 in macrophages increased the amount of R5-6 bound to the cell surface. Treatment of macrophages with 0.2 μg/ml R5-6 elevated ATP binding cassette A1 (ABCA1) protein level by ~72% and apoAI-mediated cholesterol efflux by ~39%. In addition, the medium harvested from cells overexpressing R5-6 or R5-6C (R5-6- and R5-6C-conditioned media, respectively) also up-regulated ABCA1 protein expression, which was associated with accelerated cholesterol efflux and enhanced phosphorylation of phosphatidylinositol 3 kinase (PI3K) and specificity protein-1 (Sp1) in macrophages. The increased ABCA1 expression and cholesterol efflux by R5-6- and R5-6C-conditioned media were diminished by Sp1 or PI3K inhibitors mithramycin A and LY294002. Further, the cholesterol accumulation induced by apoB-containing, apoE-free lipoproteins was significantly less in macrophages incubated with R5-6- or R5-6C-conditioned medium than in those incubated with control conditioned medium. Knockdown of apoER2 or VLDLR attenuated the inhibitory role of R5-6-conditioned medium against lipoprotein-induced cholesterol accumulation. These results suggest that the reelin subregion R5-6 can serve as a tool for studying the role of apoER2 and VLDLR in atherogenesis. PMID:26317415

  13. High-Density Lipoprotein Function Measurement in Human Studies: Focus on Cholesterol Efflux Capacity.

    PubMed

    Rohatgi, Anand

    2015-01-01

    A low plasma level of high-density lipoprotein (HDL) cholesterol (HDL-C) is a major risk factor for the development of atherosclerotic cardiovascular disease (ASCVD). However, several observations have highlighted the shortcomings of using cholesterol content as the sole reflection of HDL metabolism. In particular, several large randomized controlled trials of extended release niacin and cholesteryl-ester transfer protein (CETP) inhibitors on background statin therapy have failed to show improvement in ASCVD outcomes despite significant increases in HDL-C. Reverse cholesterol transport (RCT) is the principal HDL function that impacts macrophage foam cell formation and other functions such as endothelial activation of endothelial nitric oxide synthase, monocyte adhesion, and platelet aggregation. Cholesterol efflux from macrophages to plasma/serum reflects the first critical step of RCT and is considered a key anti-atherosclerotic function of HDL. Whether this function is operative in humans remains to be seen, but recent studies assessing cholesterol efflux in humans suggest that the cholesterol efflux capacity (CEC) of human plasma or serum is a potent marker of ASCVD risk. This review describes the methodology of measuring CEC ex vivo from human samples and the findings to date linking CEC to human disease. Studies to date confirm that CEC can be reliably measured using stored human blood samples as cholesterol acceptors and suggest that CEC may be a promising new biomarker for atherosclerotic and metabolic diseases. Further studies are needed to standardize measurements and clarify the role CEC may play in predicting risk of developing disease and response to therapies. PMID:25968932

  14. High-Density Lipoprotein Function Measurement in Human Studies: Focus on Cholesterol Efflux Capacity

    PubMed Central

    Rohatgi, Anand

    2015-01-01

    A low plasma level of high-density lipoprotein (HDL) cholesterol (HDL-C) is a major risk factor for the development of atherosclerotic cardiovascular disease (ASCVD). However, several observations have highlighted the shortcomings of using cholesterol content as the sole reflection of HDL metabolism. In particular, several large randomized controlled trials of extended release niacin and cholesteryl-ester transfer protein (CETP) inhibitors on background statin therapy have failed to show improvement in ASCVD outcomes despite significant increases in HDL-C. Reverse cholesterol transport (RCT) is the principal HDL function that impacts macrophage foam cell formation and other functions such as endothelial activation of endothelial nitric oxide synthase, monocyte adhesion, and platelet aggregation. Cholesterol efflux from macrophages to plasma/serum reflects the first critical step of RCT and is considered a key anti-atherosclerotic function of HDL. Whether this function is operative in humans remains to be seen, but recent studies assessing cholesterol efflux in humans suggest that the cholesterol efflux capacity (CEC) of human plasma or serum is a potent marker of ASCVD risk. This review describes the methodology of measuring CEC ex vivo from human samples and the findings to date linking CEC to human disease. Studies to date confirm that CEC can be reliably measured using stored human blood samples as cholesterol acceptors and suggest that CEC may be a promising new biomarker for atherosclerotic and metabolic diseases. Further studies are needed to standardize measurements and clarify the role CEC may play in predicting risk of developing disease and response to therapies. PMID:25968932

  15. High-Density Lipoprotein Function Measurement in Human Studies: Focus on Cholesterol Efflux Capacity.

    PubMed

    Rohatgi, Anand

    2015-01-01

    A low plasma level of high-density lipoprotein (HDL) cholesterol (HDL-C) is a major risk factor for the development of atherosclerotic cardiovascular disease (ASCVD). However, several observations have highlighted the shortcomings of using cholesterol content as the sole reflection of HDL metabolism. In particular, several large randomized controlled trials of extended release niacin and cholesteryl-ester transfer protein (CETP) inhibitors on background statin therapy have failed to show improvement in ASCVD outcomes despite significant increases in HDL-C. Reverse cholesterol transport (RCT) is the principal HDL function that impacts macrophage foam cell formation and other functions such as endothelial activation of endothelial nitric oxide synthase, monocyte adhesion, and platelet aggregation. Cholesterol efflux from macrophages to plasma/serum reflects the first critical step of RCT and is considered a key anti-atherosclerotic function of HDL. Whether this function is operative in humans remains to be seen, but recent studies assessing cholesterol efflux in humans suggest that the cholesterol efflux capacity (CEC) of human plasma or serum is a potent marker of ASCVD risk. This review describes the methodology of measuring CEC ex vivo from human samples and the findings to date linking CEC to human disease. Studies to date confirm that CEC can be reliably measured using stored human blood samples as cholesterol acceptors and suggest that CEC may be a promising new biomarker for atherosclerotic and metabolic diseases. Further studies are needed to standardize measurements and clarify the role CEC may play in predicting risk of developing disease and response to therapies.

  16. Human apolipoprotein E allele and docosahexaenoic acid intake modulate peripheral cholesterol homeostasis in mice.

    PubMed

    Pinçon, Anthony; Coulombe, Jean-Denis; Chouinard-Watkins, Raphaël; Plourde, Mélanie

    2016-08-01

    Carrying at least one apolipoprotein E ε4 allele (E4+) is the main genetic risk factor for Alzheimer's disease (AD). Epidemiological studies support that consuming fatty fish rich in docosahexaenoic acid (DHA; 22:6ω3) is protective against development of AD. However, this protective effect seems not to hold in E4+. The involvement of APOE genotype on the relationship between DHA intake and cognitive decline could be mediated through cholesterol. Many studies show a link between cholesterol metabolism and AD progression. In this study, we investigated whether cholesterol metabolism is improved in E3+ and E4+ mice consuming a diet rich in DHA. Plasma cholesterol was 36% lower in E4+ mice compared to E3+ mice fed the control diet (P=.02), and in the liver, there was a significant genotype effect where cholesterol levels were 18% lower in E4+ mice than E3+ mice. The low-density lipoprotein receptor was overexpressed in the liver of E4+ mice. Plasma cholesterol levels were 33% lower after the DHA diet (P=.02) in E3+ mice only, and there was a significant diet effect where cholesterol level was 67% lower in the liver of mice fed DHA. Mice fed the DHA diet also had 62% less lipolysis stimulated lipoprotein receptor expression in the liver compared to mice fed the control diet (P<.0001), but there was no genotype effect. These findings suggest that plasma and liver cholesterol homeostasis and the receptors regulating uptake of cholesterol in the liver are modulated differently and independently by APOE allele and DHA intake.

  17. Treating low high-density lipoprotein cholesterol: what is the evidence?

    PubMed Central

    Hage, Mirella P.

    2014-01-01

    Epidemiological studies have shown an inverse association between high-density lipoprotein cholesterol (HDL-C) and cardiovascular disease (CVD) risk. However, genetic and interventional studies have failed to consistently support this relationship. There is an increasing body of evidence that the function of HDL, including its antiatherogenic properties and its reverse cholesterol transport activity, has a greater impact on CVD risk compared with levels of HDL alone. Targeting HDL has become a growing interest. Nevertheless, raising HDL pharmacologically has failed to show a considerable, if any, impact on cardiovascular outcome. Efforts should focus on improving HDL quality in addition to raising HDL levels when developing new therapies. Ongoing and future research will help determine the most safe and effective approach to improve cardiovascular outcome and establish the safety, efficacy and impact on atherosclerosis of the emerging HDL-raising therapies. PMID:24696776

  18. High density lipoprotein cholesterol: an evolving target of therapy in the management of cardiovascular disease

    PubMed Central

    Kapur, Navin K; Ashen, Dominique; Blumenthal, Roger S

    2008-01-01

    Since the pioneering work of John Gofman in the 1950s, our understanding of high density lipoprotein cholesterol (HDL-C) and its relationship to coronary heart disease (CHD) has grown substantially. Numerous clinical trials since the Framingham Study in 1977 have demonstrated an inverse relationship between HDL-C and one’s risk of developing CHD. Over the past two decades, preclinical research has gained further insight into the nature of HDL-C metabolism, specifically regarding the ability of HDL-C to promote reverse cholesterol transport (RCT). Recent attempts to harness HDL’s ability to enhance RCT have revealed the complexity of HDL-C metabolism. This review provides a detailed update on HDL-C as an evolving therapeutic target in the management of cardiovascular disease. PMID:18629371

  19. 21-Methylpyrenyl-cholesterol stably and specifically associates with lipoprotein peripheral hemi-membrane: A new labelling tool

    SciTech Connect

    Gaibelet, Gérald; Tercé, François; Bertrand-Michel, Justine; Allart, Sophie; Azalbert, Vincent; Lecompte, Marie-France; Collet, Xavier; Orlowski, Stéphane

    2013-11-01

    Highlights: •21-Methylpyrenyl-cholesterol specifically and stably associates to lipoproteins. •It is not esterified by LCAT, and thus reliably labels their peripheral hemi-membrane. •HDL vs. LDL are well distinguishable by various fluorescent labelling characteristics. •LDL peripheral hemi-membrane harbors cholesterol-rich ordered lipid (micro)domains. •Cultured cells can be stained by such labelled lipoproteins-mediated delivery. -- Abstract: Lipoproteins are important biological components. However, they have few convenient fluorescent labelling probes currently reported, and their physiological reliability can be questioned. We compared the association of two fluorescent cholesterol derivatives, 22-nitrobenzoxadiazole-cholesterol (NBD-Chol) and 21-methylpyrenyl-cholesterol (Pyr-met-Chol), to serum lipoproteins and to purified HDL and LDL. Both lipoproteins could be stably labelled by Pyr-met-Chol, but virtually not by NBD-Chol. At variance with NBD-Chol, LCAT did not esterify Pyr-met-Chol. The labelling characteristics of lipoproteins by Pyr-met-Chol were well distinguishable between HDL and LDL, regarding dializability, associated probe amount and labelling kinetics. We took benefit of the pyrene labelling to approach the structural organization of LDL peripheral hemi-membrane, since Pyr-met-Chol-labelled LDL, but not HDL, presented a fluorescence emission of pyrene excimers, indicating that the probe was present in an ordered lipid micro-environment. Since the peripheral membrane of LDL contains more sphingomyelin (SM) than HDL, this excimer formation was consistent with the existence of cholesterol- and SM-enriched lipid microdomains in LDL, as already suggested in model membranes of similar composition and reminiscent to the well-described “lipid rafts” in bilayer membranes. Finally, we showed that Pyr-met-Chol could stain cultured PC-3 cells via lipoprotein-mediated delivery, with a staining pattern well different to that observed with NBD

  20. Drinking deep seawater decreases serum total and low-density lipoprotein-cholesterol in hypercholesterolemic subjects.

    PubMed

    Fu, Zhao-Yang; Yang, Feili Lo; Hsu, Hsin-Wen; Lu, Yi-Fa

    2012-06-01

    Drinking deep seawater (DSW) with high levels of magnesium (Mg) decreased serum lipids in animal studies. Therefore the effects of drinking DSW on blood lipids and its antioxidant capacity in hypercholesterolemic subjects were investigated. DSW was first prepared by a process of filtration and reverse osmosis, and then the concentrated DSW with high levels of Mg was diluted as drinking DSW. Forty-two hypercholesterolemic volunteers were randomly divided into three groups: reverse osmotic (RO) water, DSW (Mg: 395 mg/L, hardness 1410 ppm), and magnesium-chloride fortified (MCF) water (Mg: 386 mg/L, hardness 1430 ppm). The subjects drank 1050 mL of water daily for 6 weeks, and blood samples were collected and analyzed on weeks 0, 3, and 6. Drinking DSW caused a decrease in blood total cholesterol levels and this effect was progressively enhanced with time. Serum low-density lipoprotein-cholesterol (LDL-C) was also decreased by DSW. Further, total cholesterol levels of subjects in the DSW group were significantly lower than those in the MCF water or RO water groups. Compared with week 0, the DSW group had higher blood Mg level on weeks 3 and 6, but the Mg levels were within the normal range in all three groups. DSW consumption also lowered thiobarbituric acid-reactive substances (TBARS) values in serum. In conclusion, DSW was apparently effective in reducing blood total cholesterol and LDL-C, and also in decreasing lipid peroxidation in hypercholesterolemic subjects.

  1. Low-Density Lipoprotein Cholesterol, Non-High-Density Lipoprotein Cholesterol, Triglycerides, and Apolipoprotein B and Cardiovascular Risk in Patients With Manifest Arterial Disease.

    PubMed

    van den Berg, M Johanneke; van der Graaf, Yolanda; de Borst, Gert Jan; Kappelle, L Jaap; Nathoe, Hendrik M; Visseren, Frank L J

    2016-09-15

    Low-density lipoprotein cholesterol (LDL-C) only partly represents the atherogenic lipid burden, and a growing body of evidence suggests that non-high-density lipoprotein cholesterol (non-HDL-C), triglycerides, and apolipoprotein B (apoB) are more accurate in estimating lipid-related cardiovascular disease risk. Our objective was to compare the relation among LDL-C, non-HDL-C, triglycerides, and apoB and the occurrence of future vascular events and mortality in patients with manifest arterial disease. This is a prospective cohort study of 7,216 patients with clinically manifest arterial disease in the Secondary Manifestations of Arterial Disease Study. Cox proportional hazard models were used to quantify the risk of major cardiovascular events (MACE; i.e., stroke, myocardial infarction, and vascular mortality) and all-cause mortality. Interaction was tested for type of vascular disease at inclusion. MACE occurred in 1,185 subjects during a median follow-up of 6.5 years (interquartile range 3.4 to 9.9 years). Adjusted hazard ratios (HRs) of MACE per 1 SD higher were for LDL-C (HR 1.15, 95% confidence interval [CI] 1.09 to 1.22), for non-HDL-C (HR 1.17, 95% CI 1.11 to 1.23), for log(triglycerides) (HR 1.12, 95% CI 1.06 to 1.19), and for apoB HR (1.12, 95% CI 0.99 to 1.28). The relation among LDL-C, non-HDL-C, and cardiovascular events was comparable in patients with cerebrovascular disease, coronary artery disease, or polyvascular disease and absent in those with aneurysm of abdominal aorta or peripheral artery disease. In conclusion, in patients with a history of cerebrovascular, coronary artery, or polyvascular disease, but not aneurysm of abdominal aorta or peripheral artery disease, higher levels of LDL-C and non-HDL-C are related to increased risk of future MACE and of comparable magnitude.

  2. Low-Density Lipoprotein Cholesterol, Non-High-Density Lipoprotein Cholesterol, Triglycerides, and Apolipoprotein B and Cardiovascular Risk in Patients With Manifest Arterial Disease.

    PubMed

    van den Berg, M Johanneke; van der Graaf, Yolanda; de Borst, Gert Jan; Kappelle, L Jaap; Nathoe, Hendrik M; Visseren, Frank L J

    2016-09-15

    Low-density lipoprotein cholesterol (LDL-C) only partly represents the atherogenic lipid burden, and a growing body of evidence suggests that non-high-density lipoprotein cholesterol (non-HDL-C), triglycerides, and apolipoprotein B (apoB) are more accurate in estimating lipid-related cardiovascular disease risk. Our objective was to compare the relation among LDL-C, non-HDL-C, triglycerides, and apoB and the occurrence of future vascular events and mortality in patients with manifest arterial disease. This is a prospective cohort study of 7,216 patients with clinically manifest arterial disease in the Secondary Manifestations of Arterial Disease Study. Cox proportional hazard models were used to quantify the risk of major cardiovascular events (MACE; i.e., stroke, myocardial infarction, and vascular mortality) and all-cause mortality. Interaction was tested for type of vascular disease at inclusion. MACE occurred in 1,185 subjects during a median follow-up of 6.5 years (interquartile range 3.4 to 9.9 years). Adjusted hazard ratios (HRs) of MACE per 1 SD higher were for LDL-C (HR 1.15, 95% confidence interval [CI] 1.09 to 1.22), for non-HDL-C (HR 1.17, 95% CI 1.11 to 1.23), for log(triglycerides) (HR 1.12, 95% CI 1.06 to 1.19), and for apoB HR (1.12, 95% CI 0.99 to 1.28). The relation among LDL-C, non-HDL-C, and cardiovascular events was comparable in patients with cerebrovascular disease, coronary artery disease, or polyvascular disease and absent in those with aneurysm of abdominal aorta or peripheral artery disease. In conclusion, in patients with a history of cerebrovascular, coronary artery, or polyvascular disease, but not aneurysm of abdominal aorta or peripheral artery disease, higher levels of LDL-C and non-HDL-C are related to increased risk of future MACE and of comparable magnitude. PMID:27471056

  3. Accelerated decline in renal function after acute myocardial infarction in patients with high low-density lipoprotein-cholesterol to high-density lipoprotein-cholesterol ratio.

    PubMed

    Okumura, Satoshi; Sakakibara, Masaki; Hayashida, Ryo; Jinno, Yasushi; Tanaka, Akihito; Okada, Koji; Hayashi, Mutsuharu; Ishii, Hideki; Murohara, Toyoaki

    2014-01-01

    High low-density lipoprotein-cholesterol to high-density lipoprotein-cholesterol (L/H) ratio is associated with progressions of coronary arteriosclerosis and chronic kidney disease. On the other hand, renal function markedly declined after acute myocardial infarction (AMI). The aims of the present study were (1) to identify what type of patients with AMI would have high L/H ratio at follow-up and (2) to evaluate whether decline in renal function after AMI had accelerated or not in patients with high L/H ratio. The 190 eligible AMI patients who underwent primary percutaneous coronary intervention (PCI) and received atorvastatin (10 mg) were divided into one of two groups according to the L/H ratio at 6-month follow-up: L/H >2 group (n = 81) or L/H ≤2 group (n = 109). The characteristics on admission in the two groups were examined. Furthermore, changes in serum creatinine (sCr) and estimated glomerular filtration rate (eGFR) during 1- and 6-month follow-up were compared between the two groups. L/H >2 group were significantly younger and had greater body mass index (BMI) and worse lipid profile on admission compared with L/H ≤2 group. Percentage increase in sCr and percentage decrease in eGFR during 1-month follow-up in L/H >2 group tended to be greater than in L/H ≤2 group, and those during 6-month follow-up were significantly greater (16.5 ± 2.77 vs. 9.79 ± 2.23 %, p = 0.03 and 11.8 ± 1.93 vs. 2.75 ± 3.85 %, p = 0.04, respectively). In AMI patients undergoing primary PCI, those who were young and had large BMI and poor lipid profile on admission were likely to have a high L/H ratio at follow-up despite statin therapy. In addition, the decline in renal function after AMI had significantly accelerated in patients with high L/H ratio.

  4. Effect of dietary cholesterol with or without saturated fat on plasma lipoprotein cholesterol levels in the laboratory opossum (Monodelphis domestica) model for diet-induced hyperlipidaemia.

    PubMed

    Kushwaha, Rampratap S; VandeBerg, Jane F; VandeBerg, John L

    2004-07-01

    Laboratory opossums (Monodelphis domestica) show extreme genetic variability in their responsiveness to dietary lipids; a great proportion of the genetic variability in responsiveness is due to a single major gene. To determine whether the major gene for dietary response detected by genetic analysis in opossums is responsive to dietary cholesterol or dietary saturated fat, or a combination of both, we used males and females of susceptible and resistant lines of laboratory opossums that were 5 to 7 months old. The animals were challenged with three different experimental diets (high-cholesterol diets with or without high saturated fat from lard or coconut oil) and plasma lipoproteins were measured. Plasma and VLDL+LDL-cholesterol concentrations increased several-fold when the animals were fed the diet containing elevated cholesterol (P<0.001) or elevated cholesterol and fat (P<0.001) and differed between the two lines when they were fed high-cholesterol diets with or without fat (P<0.001). Plasma HDL-cholesterol concentrations were higher (P<0.05) in animals of the resistant line than in the susceptible line when they were fed the basal diet (550 (SEM 30) v. 440 (SEM 20) mg/l) and when they were fed the low-cholesterol and high-fat diet (600 (SEM 30) v. 490 (SEM 30) mg/l). Dietary coconut oil and lard had similar effects on plasma lipoprotein cholesterol concentrations in the susceptible line of opossums. A reduction in dietary cholesterol by 50 % with either the lard or coconut oil blunted the plasma cholesterol response. The results from the present studies suggest that the major gene for dietary response previously detected by genetic analysis in laboratory opossums affects the response to dietary cholesterol but not to saturated fat.

  5. Targeting PCSK9 as a promising new mechanism for lowering low-density lipoprotein cholesterol.

    PubMed

    Della Badia, Laura A; Elshourbagy, Nabil A; Mousa, Shaker A

    2016-08-01

    Statins and other lipid-lowering drugs have dominated the market for many years for achievement of recommended levels of low-density lipoprotein cholesterol (LDL-C). However, a substantial number of high-risk patients are unable to achieve the LDL-C goal. Proprotein convertase subtilisin/kexin 9 (PCSK9) has recently emerged as a new, promising key therapeutic target for hypercholesterolemia. PCSK9 is a protease involved in chaperoning the low-density lipoprotein receptor to the process of degradation. PCSK9 inhibitors and statins effectively lower LDL-C. The PCSK9 inhibitors decrease the degradation of the LDL receptors, whereas statins mainly interfere with the synthetic machinery of cholesterol by inhibiting the key rate limiting enzyme, the HMG CoA reductase. PCSK9 inhibitors are currently being developed as monoclonal antibodies for their primary use in lowering LDL-C. They may be especially useful for patients with homozygous familial hypercholesterolemia, who at present receive minimal benefit from traditional statin therapy. The monoclonal antibody PCSK9 inhibitors, recently granted FDA approval, show the most promising safety and efficacy profile compared to other, newer LDL-C lowering therapies. This review will primarily focus on the safety and efficacy of monoclonal antibody PCSK9 inhibitors in comparison to statins. The review will also address new, alternative PCSK9 targeting drug classes such as small molecules, gene silencing agents, apolipoprotein B antisense oligonucleotides, and microsomal triglyceride transfer protein inhibitors.

  6. Targeting PCSK9 as a promising new mechanism for lowering low-density lipoprotein cholesterol.

    PubMed

    Della Badia, Laura A; Elshourbagy, Nabil A; Mousa, Shaker A

    2016-08-01

    Statins and other lipid-lowering drugs have dominated the market for many years for achievement of recommended levels of low-density lipoprotein cholesterol (LDL-C). However, a substantial number of high-risk patients are unable to achieve the LDL-C goal. Proprotein convertase subtilisin/kexin 9 (PCSK9) has recently emerged as a new, promising key therapeutic target for hypercholesterolemia. PCSK9 is a protease involved in chaperoning the low-density lipoprotein receptor to the process of degradation. PCSK9 inhibitors and statins effectively lower LDL-C. The PCSK9 inhibitors decrease the degradation of the LDL receptors, whereas statins mainly interfere with the synthetic machinery of cholesterol by inhibiting the key rate limiting enzyme, the HMG CoA reductase. PCSK9 inhibitors are currently being developed as monoclonal antibodies for their primary use in lowering LDL-C. They may be especially useful for patients with homozygous familial hypercholesterolemia, who at present receive minimal benefit from traditional statin therapy. The monoclonal antibody PCSK9 inhibitors, recently granted FDA approval, show the most promising safety and efficacy profile compared to other, newer LDL-C lowering therapies. This review will primarily focus on the safety and efficacy of monoclonal antibody PCSK9 inhibitors in comparison to statins. The review will also address new, alternative PCSK9 targeting drug classes such as small molecules, gene silencing agents, apolipoprotein B antisense oligonucleotides, and microsomal triglyceride transfer protein inhibitors. PMID:27133571

  7. Lowering low-density lipoprotein cholesterol levels in patients with type 2 diabetes mellitus

    PubMed Central

    Bays, Harold E

    2014-01-01

    Type 2 diabetes mellitus (T2DM) is characterized by hyperglycemia, insulin resistance, and/or progressive loss of β-cell function. T2DM patients are at increased risk of micro- and macrovascular disease, and are often considered as representing an atherosclerotic coronary heart disease (CHD) risk equivalent. Interventions directed at glucose and lipid level control in T2DM patients may reduce micro- and macrovascular disease. The optimal T2DM agent is one that lowers glucose levels with limited risk for hypoglycemia, and with no clinical trial evidence of worsening CHD risk. Lipid-altering drugs should preferably reduce low-density lipoprotein cholesterol and apolipoprotein B (apo B) and have evidence that the mechanism of action reduces CHD risk. Statins reduce low-density lipoprotein cholesterol and apo B and have evidence of improving CHD outcomes, and are thus first-line therapy for the treatment of hypercholesterolemia. In patients who do not achieve optimal lipid levels with statin therapy, or who are intolerant to statin therapy, add-on therapy or alternative therapies may be indicated. Additional available agents to treat hypercholesterolemic patients with T2DM include bile acid sequestrants, fibrates, niacin, and ezetimibe. This review discusses the use of these alternative agents to treat hypercholesterolemia in patients with T2DM, either as monotherapy or in combination with statin therapy. PMID:25045281

  8. Role of non-high-density lipoprotein cholesterol in predicting cerebrovascular events in patients following myocardial infarction.

    PubMed

    Mahajan, Nitin; Ference, Brian A; Arora, Natasha; Madhavan, Ramesh; Bhattacharya, Pratik; Sudhakar, Rajeev; Sagar, Amit; Wang, Yun; Sacks, Frank; Afonso, Luis

    2012-06-15

    Although there appears to be a role for statins in reducing cerebrovascular events, the exact role of different lipid fractions in the etiopathogenesis of cerebrovascular disease (CVD) is not well understood. A secondary analysis of data collected for the placebo arm (n = 2,078) of the Cholesterol and Recurrent Events (CARE) trial was performed. The CARE trial was a placebo-controlled trial aimed at testing the effect of pravastatin on patients after myocardial infarction. Patients with histories of CVD were excluded from the study. A Cox proportional-hazards model was used to evaluate the association between plausible risk factors (including lipid fractions) and risk for first incident CVD in patients after myocardial infarction. At the end of 5 years, 123 patients (6%) had incident CVD after myocardial infarction (76 with stroke and 47 with transient ischemic attack). Baseline non-high-density lipoprotein (HDL) cholesterol level emerged as the only significant lipid risk factor that predicted CVD; low-density lipoprotein cholesterol and HDL cholesterol were not significant. The adjusted hazard ratios (adjusted for age, gender, hypertension, diabetes mellitus, and smoking) for CVD were 1.28 (95% confidence interval [CI] 1.06 to 1.53) for non-HDL cholesterol, 1.14 (95% CI 0.96 to 1.37) for low-density lipoprotein cholesterol, and 0.90 (95% CI 0.75 to 1.09) for HDL cholesterol (per unit SD change of lipid fractions). This relation held true regardless of the level of triglycerides. After adjustment for age and gender, the hazard ratio for the highest natural quartile of non-HDL was 1.76 (95% CI 1.05 to 2.54), compared to 1.36 (95% CI 0.89 to 1.90) for low-density lipoprotein cholesterol. In conclusion, non-HDL cholesterol is the strongest predictor among the lipid risk factors of incident CVD in patients with established coronary heart disease.

  9. Cholesterol induces lipoprotein lipase expression in a tree shrew (Tupaia belangeri chinensis) model of non-alcoholic fatty liver disease.

    PubMed

    Zhang, Linqiang; Zhang, Zhiguo; Li, Yunhai; Liao, Shasha; Wu, Xiaoyun; Chang, Qing; Liang, Bin

    2015-01-01

    Animal models are indispensible to investigate the pathogenesis and treatments of non-alcoholic fatty liver diseases (NAFLD). Altered cholesterol metabolism has been implicated into the pathogenesis of NAFLD. Here, using high fat, cholesterol and cholate diet (HFHC), we generated a novel tree shrew (Tupaia belangeri chinensis) model of NAFLD, which displayed dyslipidemia with increased levels of plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST), total cholesterol (TC), low density lipoprotein-cholesterol (LDL-c) and high density lipoprotein-cholesterol (HDL-c), but decreased level of triglycerides (TG). Liver histopathology and genes expression indicated that HFHC diet successfully induced liver steatosis to inflammation and fibrosis progressively within 10 weeks. Moreover, HFHC induced the transcriptional expression of lipoprotein lipase (lpl) in the liver, but repressed the expression of LDL receptor, and the endogenous synthesis pathway and excretion of cholesterol. Notably, Poloxamer 407 (P-407) inhibition of LPL improved the severity of steatosis and reduced inflammation. These results illustrated that LPL plays an important role in cholesterol metabolism in NAFLD, and the tree shrew may be a valuable animal model for further research into NAFLD. PMID:26522240

  10. Modulation of infant formula fat profile alters the low-density lipoprotein/high-density lipoprotein ratio and plasma fatty acid distribution relative to those with breast-feeding.

    PubMed

    Hayes, K C; Pronczuk, A; Wood, R A; Guy, D G

    1992-04-01

    The effect of breast-feeding was compared with that of two fat-modified milk formulas in 45 infants (15 per group) studied by assessing body weight gain for 4 months and plasma lipids, lipoprotein profiles, fatty acid profiles of plasma and red blood cells, and plasma tocopherol status 3 months after birth. A saturated fat formula with coconut oil/soybean oil (COCO/SOY) had a fatty acid content and polyunsaturated/saturated ratio (P/S, 0.55) comparable with that of human milk fat (P/S, 0.39) and had the same fat energy content (50% kcal). The second formula, with corn oil/soybean oil (CORN/SOY), was highly unsaturated (P/S, 4.6), with only 35% kcal from fat. Energy intake and body weight gain were similar for all groups. Plasma total cholesterol, triglyceride, and phospholipid levels were significantly lower (greater than 20% on average) in infants fed the CORN/SOY formula than in infants fed either the COCO/SOY formula or human milk. Infants fed the CORN/SOY formula also had lower (25% to 35%) plasma low-density lipoprotein cholesterol and apolipoprotein B levels and low-density lipoprotein/high-density lipoprotein and apolipoprotein B/apolipoprotein A-I ratios. Plasma, red blood cell, and cholesteryl ester fatty acids from infants fed COCO/SOY contained less 18:1 and more 18:2; cholesterol esters in plasma from breast-fed infants had the highest 20:4n-6 levels. Plasma tocopherol levels were higher in infants consuming formulas. The presence of cholesterol in human milk appeared to expand the low-density lipoprotein pool and exert an "unfavorable" increase in the low-density lipoprotein/high-density lipoprotein ratio. Thus modulation of infant lipoproteins by changing dietary fat and cholesterol is feasible and in keeping with the known response in adults. PMID:1560323

  11. 21-Methylpyrenyl-cholesterol stably and specifically associates with lipoprotein peripheral hemi-membrane: a new labelling tool.

    PubMed

    Gaibelet, Gérald; Tercé, François; Bertrand-Michel, Justine; Allart, Sophie; Azalbert, Vincent; Lecompte, Marie-France; Collet, Xavier; Orlowski, Stéphane

    2013-11-01

    Lipoproteins are important biological components. However, they have few convenient fluorescent labelling probes currently reported, and their physiological reliability can be questioned. We compared the association of two fluorescent cholesterol derivatives, 22-nitrobenzoxadiazole-cholesterol (NBD-Chol) and 21-methylpyrenyl-cholesterol (Pyr-met-Chol), to serum lipoproteins and to purified HDL and LDL. Both lipoproteins could be stably labelled by Pyr-met-Chol, but virtually not by NBD-Chol. At variance with NBD-Chol, LCAT did not esterify Pyr-met-Chol. The labelling characteristics of lipoproteins by Pyr-met-Chol were well distinguishable between HDL and LDL, regarding dializability, associated probe amount and labelling kinetics. We took benefit of the pyrene labelling to approach the structural organization of LDL peripheral hemi-membrane, since Pyr-met-Chol-labelled LDL, but not HDL, presented a fluorescence emission of pyrene excimers, indicating that the probe was present in an ordered lipid micro-environment. Since the peripheral membrane of LDL contains more sphingomyelin (SM) than HDL, this excimer formation was consistent with the existence of cholesterol- and SM-enriched lipid microdomains in LDL, as already suggested in model membranes of similar composition and reminiscent to the well-described "lipid rafts" in bilayer membranes. Finally, we showed that Pyr-met-Chol could stain cultured PC-3 cells via lipoprotein-mediated delivery, with a staining pattern well different to that observed with NBD-Chol non-specifically delivered to the cells. PMID:24103760

  12. Improved cholesterol phenotype analysis by a model relating lipoprotein life cycle processes to particle size[S

    PubMed Central

    van Schalkwijk, Daniël B.; de Graaf, Albert A.; van Ommen, Ben; van Bochove, Kees; Rensen, Patrick C. N.; Havekes, Louis M.; van de Pas, Niek C. A.; Hoefsloot, Huub C. J.; van der Greef, Jan; Freidig, Andreas P.

    2009-01-01

    Increased plasma cholesterol is a known risk factor for cardiovascular disease. Lipoprotein particles transport both cholesterol and triglycerides through the blood. It is thought that the size distribution of these particles codetermines cardiovascular disease risk. New types of measurements can determine the concentration of many lipoprotein size-classes but exactly how each small class relates to disease risk is difficult to clear up. Because relating physiological process status to disease risk seems promising, we propose investigating how lipoprotein production, lipolysis, and uptake processes depend on particle size. To do this, we introduced a novel model framework (Particle Profiler) and evaluated its feasibility. The framework was tested using existing stable isotope flux data. The model framework implementation we present here reproduced the flux data and derived lipoprotein size pattern changes that corresponded to measured changes. It also sensitively indicated changes in lipoprotein metabolism between patient groups that are biologically plausible. Finally, the model was able to reproduce the cholesterol and triglyceride phenotype of known genetic diseases like familial hypercholesterolemia and familial hyperchylomicronemia. In the future, Particle Profiler can be applied for analyzing detailed lipoprotein size profile data and deriving rates of various lipolysis and uptake processes if an independent production estimate is given. PMID:19515990

  13. Cholesterol forms and traditional lipid profile for projection of atherogenic dyslipidemia: lipoprotein subfractions and erythrocyte membrane cholesterol.

    PubMed

    Uydu, Hüseyin Avni; Bostan, Mehmet; Atak, Mehtap; Yılmaz, Adnan; Demir, Adem; Akçan, Buket; Sümer, Fatih; Baltaş, Nimet; Karadağ, Zakir; Uğurlu, Yavuz; Orem, Asım

    2014-02-01

    Atherogenic dyslipidemia characterized by abnormal changes in plasma lipid profile such as low high-density lipoprotein (HDL) and increased triglyceride (TG) levels is strongly associated with atherosclerotic diseases. We aimed to evaluate the levels of pro- and antiatherogenic lipids and erythrocyte membrane cholesterol (EMC) content in normo- and dyslipidemic subjects to investigate whether EMC content could be a useful marker for clinical presentation of atherogenic dyslipidemia. Low-density lipoprotein (LDL), HDL and their subfraction levels and erythrocyte lipid content were determined in 64 normolipidemic (NLs), 42 hypercholesterolemic (HCs) and 42 mixed-type dyslipidemic subjects (MTDs). Plasma atherogenic lipid indices [small-dense LDL (sdLDL)/less-dense HDL (LHDL), TC/HDL-C, TG/HDL-C and Apo B/AI] were higher in MTDs compared to NLs (p < 0.001). The highest sdLDL level was observed in HCs (p < 0.01). Despite a slight increase in EMC level in dyslipidemic subgroups, the difference was not statistically significant. A significant negative correlation, however, was observed between EMC and sdLDL/LHDL in HCs (p < 0.035, r = -0.386). Receiver operating characteristic curves to predict sdLDL level showed that TG and EMC levels had higher area under curve values compared to other parameters in HCs. We showed that diameters of larger LDL and HDL particles tend to shift toward smaller values in MTDs. Our results suggest that EMC content and TG levels may be a useful predictor for sdLDL level in hypercholesterolemic patients.

  14. Paradoxical Elevation of High Density Lipoprotein Cholesterol in Association with Lacunar-Type Cerebral Infarction

    PubMed Central

    Meng, Gui-Lin; Tan, Yan; Fang, Min; Yang, Hong-Yan; Liu, Xue-Yuan; Zhao, Yan-Xin

    2015-01-01

    Background The aim of this study was to evaluate the association between high-density lipoprotein cholesterol (HDLC) levels and the risk of lacunar infarction (LI) in a retrospective cohort study in China. Material/Methods We recruited 229 patients with obsolete brain infarctions single side (SOBI), 218 with obsolete brain infarctions bilateral sides (BOBI), 193 with both acute stroke and obsolete lacunar infarctions single side (AI&SOBI), 113 with both acute stroke and obsolete lacunar infarctions bilateral sides (AI&BOBI), and 203 without any infarctions (Control). Results 1) The plasma levels of HDLC in group BOBI, AI&SOBI, and AI&BOBI were higher than in the control group, and lower in group SOBI than in the control group (p<0.01). 2) The plasma levels of HDLC in group AI&SOBI were significantly higher than in group SOBI (p<0.01). 3) The plasma levels of HLDL were similar between group AI&SOBI and AI&BOBI. 4) There were significant relationships between HDLC and acute lacunar stroke, even after adjusting for these factors such as age, sex, triglyceride, total cholesterol, low-density lipoprotein cholesterol, and history of diabetes (p=0.001). 4) Compared with the controls, the calculation of odds ratios indicated relative risk estimates of higher HDLC for acute lacunar stroke with obsolete lacunar infarction. Conclusions Elevated HDLC may be an independent predictor of recurrent stroke with obsolete lacunar infarctions single side in Chinese people, justifying clinical trials for secondary prevention of stroke by generally increasing HLDL level. According to the difference between single and bilateral side multiple silent lacunar infarcts, it is inferred that HDLC may increase the risk of atherothrombotic infarction but reduce the risk of cardioembolic infarction in the general Chinese population. PMID:26120926

  15. Hepatitis C Virus, Cholesterol and Lipoproteins — Impact for the Viral Life Cycle and Pathogenesis of Liver Disease

    PubMed Central

    Felmlee, Daniel J.; Hafirassou, Mohamed Lamine; Lefevre, Mathieu; Baumert, Thomas F.; Schuster, Catherine

    2013-01-01

    Hepatitis C virus (HCV) is a leading cause of chronic liver disease, including chronic hepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. Hepatitis C infection associates with lipid and lipoprotein metabolism disorders such as hepatic steatosis, hypobetalipoproteinemia, and hypocholesterolemia. Furthermore, virus production is dependent on hepatic very-low-density lipoprotein (VLDL) assembly, and circulating virions are physically associated with lipoproteins in complexes termed lipoviral particles. Evidence has indicated several functional roles for the formation of these complexes, including co-opting of lipoprotein receptors for attachment and entry, concealing epitopes to facilitate immune escape, and hijacking host factors for HCV maturation and secretion. Here, we review the evidence surrounding pathogenesis of the hepatitis C infection regarding lipoprotein engagement, cholesterol and triglyceride regulation, and the molecular mechanisms underlying these effects. PMID:23698400

  16. High-density lipoprotein-cholesterol and diet in a healthy elderly population.

    PubMed

    Hooper, P L; Garry, P J; Goodwin, J S; Hooper, E M; Leonard, A G

    1982-01-01

    This study examined how high-density lipoprotein-cholesterol (HDL-C) correlated with a 3-day food record of fat, protein, carbohydrate, and alcohol consumption in a group of 270 healthy subjects over age 60. HDL-C concentrations correlated with alcohol consumption (expressed as grams/day) (r = + .25, P less than .001), and inversely with total carbohydrate (r = - .18, P less than .01) and refined carbohydrate (r = - .17, P less than .01) ingestion (expressed as a percent of total caloric intake). Subjects consuming diets low in either total carbohydrate or refined carbohydrate had 10 to 20% higher HDL-C levels than did those consuming diets high in these food substances. The relationships between HDL-C levels and alcohol and carbohydrate ingestion were independent of other variables which correlated with HDL-C levels. Dietary fat (total fat, saturated fat, unsaturated fat, and cholesterol) did not correlate with HDL-C. LDL-cholesterol and triglyceride levels did not correlate with any dietary variable measured.

  17. Influence of different molecular species of phosphatidylcholine on cholesterol transport from lipoprotein recombinants in the rat

    SciTech Connect

    Leduc, R.; Patton, G.M.; Atkinson, D.; Robins, S.J.

    1987-06-05

    Studies were performed to determine to what extent phosphatidylcholines (PCs) of different composition influence the turnover of lipoprotein cholesterol. Lipoprotein recombinants with the composition and structure of spherical high density lipoproteins (HDL-R) were prepared with apoproteins, /sup 14/C-labeled unesterified cholesterol (UC), a (3H)cholesteryl ester (CE), and one of four single molecular species of PC. PCs were selected to include relatively hydrophilic species (16:1-16:1 and 16:0-18:2 PCs) and relatively hydrophobic species (18:0-18:2 and 20:1-20:1 PCs). PCs were also selected to include molecules with novel acyl group pairs (16:1-16:1 and 20:1-20:1 PCs) that would permit the whole molecule to be traced during its clearance from the serum. Rats were injected with HDL-R as an intravenous bolus, and serum, liver, and bile samples were obtained for up to 2 h. The clearance from the serum of each PC was monoexponential with the two most hydrophilic species much more rapidly cleared than either of the two less hydrophilic species. Clearance of specific PCs was not accompanied by PC remodeling (i.e. transacylations), and in the main could not be attributed to the action of lecithin-cholesterol acyltransferase (LCAT). In incubations designed to simulate in vivo conditions, no more than 15% of the disappearance of 16:1-16:1 PC, one of the most rapidly cleared PCs, was due to the action of LCAT. With 20:1-20:1 PC, one of the least rapidly cleared PCs, no LCAT activity could be detected. The clearance of radiolabeled UC was multiexponential and closely corresponded to the rate of disappearance of each PC. The clearance of radiolabeled CE was linear and, in contrast to UC, was the same with the administration of different PCs. Uptake of radiolabeled UC by the liver and excretion of radiolabeled UC into bile took place in parallel and corresponded to the rapidity of turnover of UC (and PCs) in the serum.

  18. Effects of lifestyle interventions on high-density lipoprotein cholesterol levels.

    PubMed

    Roussell, Michael A; Kris-Etherton, Penny

    2007-03-01

    This review summarizes intervention studies that evaluated the effects of lifestyle behaviors on high-density lipoprotein-cholesterol (HDL-C) levels. Current diet and lifestyle recommendations beneficially affect HDL-C. Individual lifestyle interventions that increase HDL-C include: a healthful diet that is low (7-10% of calories) in saturated fat and sufficient in unsaturated fat (15-20% of calories), regular physical activity, attaining a healthy weight, with moderate alcohol consumption, and cessation of cigarette smoking. Combining a healthy diet with weight loss and physical activity can increase HDL-C 10% to 13%. When combined with interventions that beneficially affect other cardiovascular disease risk factors, this increase in HDL-C is expected to contribute to a overall reduction in cardiovascular disease risk.

  19. Usefulness of High-Density Lipoprotein Cholesterol to Predict Survival in Pulmonary Arterial Hypertension.

    PubMed

    Larsen, Carolyn M; McCully, Robert B; Murphy, Joseph G; Kushwaha, Sudhir S; Frantz, Robert P; Kane, Garvan C

    2016-07-15

    It has been suggested that lipoprotein abnormalities may contribute to the pulmonary arteriolar dysfunction observed in pulmonary arterial hypertension (PAH). High-density lipoprotein cholesterol (HDL) has vasodilatory, anti-inflammatory, and endothelial protective properties. We hypothesized that a higher serum HDL level may be advantageous for survival in PAH and that the serum HDL level at diagnosis would be an independent predictor of survival in PAH and be additive to previously validated predictors of survival. This study included all patients with PAH seen at the Mayo Clinic Pulmonary Hypertension Clinic from January 1, 1995, to December 31, 2009, who had a baseline HDL measurement. Mortality was analyzed over 5 years using the Kaplan-Meier method. Univariate and multivariable Cox proportional hazards ratios were calculated to evaluate the relation between baseline HDL level and survival. HDL levels were available for 227 patients. Higher HDL levels were associated with significantly lower mortality. Patients with an HDL >54 mg/dl at diagnosis had a 5-year survival of 59%. By comparison those with an HDL <34 mg/dl had a 5-year survival of 30%. On multivariate analysis, higher HDL was associated with an age-adjusted risk ratio for death of 0.78 (CI 0.67 to 0.91; p <0.01) per 10 mg/dl increase. In conclusion, HDL was an independent predictor of survival in PAH.

  20. Cholesterol-sensitive Modulation of Transcytosis

    PubMed Central

    Leyt, Julieta; Melamed-Book, Naomi; Vaerman, Jean-Pierre; Cohen, Shulamit; Weiss, Aryeh M.

    2007-01-01

    Cholesterol-rich membrane domains (e.g., lipid rafts) are thought to act as molecular sorting machines, capable of coordinating the organization of signal transduction pathways within limited regions of the plasma membrane and organelles. The significance of these domains in polarized postendocytic sorting is currently not understood. We show that dimeric IgA stimulates the incorporation of its receptor into cholesterol-sensitive detergent-resistant membranes confined to the basolateral surface/basolateral endosomes. A fraction of human transferrin receptor was also found in basolateral detergent-resistant membranes. Disrupting these membrane domains by cholesterol depletion (using methyl-β-cyclodextrin) before ligand-receptor internalization caused depolarization of traffic from endosomes, suggesting that cholesterol in basolateral lipid rafts plays a role in polarized sorting after endocytosis. In contrast, cholesterol depletion performed after ligand internalization stimulated cargo transcytosis. It also stimulated caveolin-1 phosphorylation on tyrosine 14 and the appearance of the activated protein in dimeric IgA-containing apical organelles. We propose that cholesterol depletion stimulates the coupling of transcytotic and caveolin-1 signaling pathways, consequently prompting the membranes to shuttle from endosomes to the plasma membrane. This process may represent a unique compensatory mechanism required to maintain cholesterol balance on the cell surface of polarized epithelia. PMID:17392516

  1. Influence of alcohol intake on high density lipoprotein cholesterol levels in middle-aged men.

    PubMed

    Gupta, R; Jain, B K; Nag, A K

    1994-01-01

    To study the influence of alcohol (ethanol) intake on high density lipoprotein cholesterol (HDLC) levels, we studied 210 healthy middle-aged men (age 45 +/- 8 years). Other factors influencing HDLC (physical exercise, diet, smoking and body mass index) were also studied. Individuals were classified according to daily ethanol consumption. There were 39 teetotallers, 29 took drink, 30 took 1-1.9, 25 took 2-2.9, 26 took 3-3.9, 28 took 4-4.9 and 33 took 5 or more drinks per day (1 drink = 14 gm ethanol). The overall mean serum total cholesterol was 191.4 +/- 53 mg/dl and HDLC was 46.4 +/- 9 mg/dl. Total cholesterol in teetotallers was not different from those consuming different amounts of alcohol. HDLC in teetotallers (44.5 +/- 8 mg/dl) was significantly lower than in those taking 1-1.9 drinks (46.7 +/- 11 mg/dl, p < 0.05) and 2-2.9 drinks/day (51.4 +/- 9 mg/dl, p < 0.01) but was not different from those consuming > or = 3.0 drinks. There was a weak positive linear correlation between ethanol and HDLC (r = 0.016). HDLC levels were significantly lower in smokers (43.5 +/- 9 vs 47.2 +/- 11 mg/dl in non-smokers), in non-vegetarians (43.5 +/- 10 vs 46.2 +/- 9 mg/dl in vegetarians) and in those with sedentary habits (42.4 +/- 7 vs 46.1 +/- 10 mg/dl in physically active). Low level ethanol consumption (< 3 drinks or 42 gm per day) is associated with increased HDLC levels.

  2. What's Cholesterol?

    MedlinePlus

    ... Most cholesterol is LDL (low-density lipoprotein) cholesterol. LDL cholesterol is more likely to clog blood vessels because ... Here's a way to remember the difference: the LDL cholesterol is the bad kind, so call it "lousy" ...

  3. Autophagy-mediated longevity is modulated by lipoprotein biogenesis

    PubMed Central

    Seah, Nicole E.; de Magalhaes Filho, C. Daniel; Petrashen, Anna P.; Henderson, Hope R.; Laguer, Jade; Gonzalez, Julissa; Dillin, Andrew; Hansen, Malene; Lapierre, Louis R.

    2016-01-01

    ABSTRACT Autophagy-dependent longevity models in C. elegans display altered lipid storage profiles, but the contribution of lipid distribution to life-span extension is not fully understood. Here we report that lipoprotein production, autophagy and lysosomal lipolysis are linked to modulate life span in a conserved fashion. We find that overexpression of the yolk lipoprotein VIT/vitellogenin reduces the life span of long-lived animals by impairing the induction of autophagy-related and lysosomal genes necessary for longevity. Accordingly, reducing vitellogenesis increases life span via induction of autophagy and lysosomal lipolysis. Life-span extension due to reduced vitellogenesis or enhanced lysosomal lipolysis requires nuclear hormone receptors (NHRs) NHR-49 and NHR-80, highlighting novel roles for these NHRs in lysosomal lipid signaling. In dietary-restricted worms and mice, expression of VIT and hepatic APOB (apolipoprotein B), respectively, are significantly reduced, suggesting a conserved longevity mechanism. Altogether, our study demonstrates that lipoprotein biogenesis is an important mechanism that modulates aging by impairing autophagy and lysosomal lipolysis. PMID:26671266

  4. Apparent selective bile acid malabsorption as a consequence of ileal exclusion: effects on bile acid, cholesterol, and lipoprotein metabolism.

    PubMed Central

    Akerlund, J E; Björkhem, I; Angelin, B; Liljeqvist, L; Einarsson, K

    1994-01-01

    A new model has been developed to characterise the effect of a standardised ileal exclusion on bile acid, cholesterol, and lipoprotein metabolism in humans. Twelve patients treated by colectomy and ileostomy for ulcerative colitis were studied on two occasions: firstly with a conventional ileostomy and then three months afterwards with an ileal pouch operation with an ileoanal anastomosis and a protective loop ileostomy, excluding on average 95 cm of the distal ileum. The ileostomy contents were collected during 96 hours and the excretion of bile acids and cholesterol was determined using gas chromatography-mass spectrometry. Fasting blood and duodenal bile samples were collected on two consecutive days. After the exclusion of the distal ileum, both cholic and chenodeoxycholic acid excretion in the ileostomy effluent increased four to five times without any change in cholesterol excretion. Serum concentrations of lathosterol (a marker of cholesterol biosynthesis) and 7 alpha-hydroxycholesterol (a marker for bile acid biosynthesis) were increased several fold. Plasma concentrations of total VLDL triglycerides were also increased whereas the concentrations of total and LDL cholesterol, and apolipoprotein B were decreased. There were no changes in biliary lipid composition or cholesterol saturation of bile. The results show that the exclusion of about 95 cm of distal ileum causes malabsorption of bile acids but apparently not of cholesterol. The bile acid malabsorption leads to increased synthesis of both bile acids and cholesterol in the liver. It is suggested that bile acids can regulate cholesterol synthesis by a mechanism independent of the effect of bile acids on cholesterol absorption. The enhanced demand for cholesterol also leads to a decrease in plasma LDL cholesterol and apolipoprotein B concentrations. The malabsorption of bile acids did not affect biliary lipid composition or cholesterol saturations of VLDL triglycerides. PMID:7926917

  5. Specific Cellular Incorporation of a Pyrene-Labelled Cholesterol: Lipoprotein-Mediated Delivery toward Ordered Intracellular Membranes

    PubMed Central

    Gaibelet, Gérald; Azalbert, Vincent; Bertrand-Michel, Justine; Hamdi, Safouane; Collet, Xavier; Orlowski, Stéphane

    2015-01-01

    In the aim of testing tools for tracing cell trafficking of exogenous cholesterol, two fluorescent derivatives of cholesterol, 22-nitrobenzoxadiazole-cholesterol (NBD-Chol) and 21-methylpyrenyl-cholesterol (Pyr-met-Chol), with distinctive chemico-physical characteristics, have been compared for their cell incorporation properties, using two cell models differently handling cholesterol, with two incorporation routes. In the Caco-2 cell model, the cholesterol probes were delivered in bile salt micelles, as a model of intestinal absorption. The two probes displayed contrasting behaviors for cell uptake characteristics, cell staining, and efflux kinetics. In particular, Pyr-met-Chol cell incorporation involved SR-BI, while that of NBD-Chol appeared purely passive. In the PC-3 cell model, which overexpresses lipoprotein receptors, the cholesterol probes were delivered via the serum components, as a model of systemic delivery. We showed that Pyr-met-Chol-labelled purified LDL or HDL were able to specifically deliver Pyr-met-Chol to the PC-3 cells, while NBD-Chol incorporation was independent of lipoproteins. Observations by fluorescence microscopy evidenced that, while NBD-Chol readily stained the cytosolic lipid droplets, Pyr-met-Chol labelling led to the intense staining of intracellular structures of membranous nature, in agreement with the absence of detectable esterification of Pyr-met-Chol. A 48 h incubation of PC-3 cells with either Pyr-met-Chol-labelled LDL or HDL gave same staining patterns, mainly colocalizing with Lamp1, caveolin-1 and CD63. These data indicated convergent trafficking downwards their respective receptors, LDL-R and SR-BI, toward the cholesterol-rich internal membrane compartments, late endosomes and multivesicular bodies. Interestingly, Pyr-met-Chol staining of these structures exhibited a high excimer fluorescence emission, revealing their ordered membrane environment, and indicating that Pyr-met-Chol behaves as a fair cholesterol tracer

  6. Dietary palmitic and oleic acids exert similar effects on serum cholesterol and lipoprotein profiles in normocholesterolemic men and women.

    PubMed

    Ng, T K; Hayes, K C; DeWitt, G F; Jegathesan, M; Satgunasingam, N; Ong, A S; Tan, D

    1992-08-01

    To compare the effects of dietary palmitic acid (16:0) vs oleic acid (18:1) on serum lipids, lipoproteins, and plasma eicosanoids, 33 normocholesterolemic subjects (20 males, 13 females; ages 22-41 years) were challenged with a coconut oil-rich diet for 4 weeks. Subsequently they were assigned to either a palm olein-rich or olive oil-rich diet followed by a dietary crossover during two consecutive 6-week periods. Each test oil served as the sole cooking oil and contributed 23% of dietary energy or two-thirds of the total daily fat intake. Dietary myristic acid (14:0) and lauric acid (12:0) from coconut oil significantly raised all the serum lipid and lipoprotein parameters measured. Subsequent one-to-one exchange of 7% energy between 16:0 (palm olein diet) and 18:1 (olive oil diet) resulted in identical serum total cholesterol (192, 193 mg/dl), low-density lipoprotein cholesterol (LDL-C) (130, 131 mg/dl), high-density lipoprotein cholesterol (HDL-C) (41, 42 mg/dl), and triglyceride (TG) (108, 106 mg/dl) concentrations. Effects attributed to gender included higher HDL in females and higher TG in males associated with the tendency for higher LDL and LDL/HDL ratios in men. However, both sexes were equally responsive to changes in dietary fat saturation. The results indicate that in healthy, normocholesterolemic humans, dietary 16:0 can be exchanged for 18:1 within the range of these fatty acids normally present in typical diets without affecting the serum lipoprotein cholesterol concentration or distribution. In addition, replacement of 12:0 + 14:0 by 16:0 + 18:1, but especially 16:0 or some component of palm olein, appeared to have a beneficial impact on an important index of thrombogenesis, i.e., the thromboxane/prostacyclin ratio in plasma.

  7. Association of dietary fiber intake with serum total cholesterol and low density lipoprotein cholesterol levels in Urban Asian-Indian adults with type 2 diabetes

    PubMed Central

    Narayan, Shreya; Lakshmipriya, Nagarajan; Vaidya, Ruchi; Bai, Mookambika Ramya; Sudha, Vasudevan; Krishnaswamy, Kamala; Unnikrishnan, Ranjit; Anjana, Ranjit Mohan; Mohan, Viswanathan

    2014-01-01

    Context: There is little data correlating dietary fibre (DF) intake and cardiovascular risk in Asian Indians with diabetes. Aim: To assess the DF intake and its association with lipid profile (total serum cholesterol and low density lipoprotein [LDL] - cholesterol levels) in urban Asian Indians with diabetes. Subjects and Methods: Dietary assessment using validated Food Frequency Questionnaire was conducted in 1191 free-living adults with known diabetes in the Chennai Urban Rural Epidemiology Study. Subjects taking medication for dyslipidemia, and those with cardiovascular disease and implausible energy intake (n = 262) were excluded, leaving 929 participants. Anthropometric and relevant biochemical parameters were measured using standardized techniques. Results: Diabetic individuals who consumed DF < median intake (29 g/day) had a higher prevalence of hypercholesterolemia (49.5% vs. 40.1% [P = 0.01]) and higher LDL cholesterol (46.2% vs. 35.5% [P = 0.001]) than those in the > median intake of DF group. The risk of hypercholesterolemia (odds ratio [OR] =1.38 [95% confidence interval [CI]: 1.02–1.85], P = 0.04), and high LDL cholesterol (OR: 1.43 [95% CI: 1.06–1.94], P = 0.02) was higher among those whose DF intake was less than the median. Serum triglycerides and high density lipoprotein cholesterol were not associated with DF intake. The main sources of DF were vegetables and legumes. Conclusion: In urban Asian Indians with diabetes, lower DF intake is positively related to total cholesterol and LDL cholesterol levels. PMID:25285277

  8. High-density lipoprotein remains elevated despite reductions in total cholesterol in fasting adult male elephant seals (Mirounga angustirostris).

    PubMed

    Tift, Michael S; Houser, Dorian S; Crocker, Daniel E

    2011-08-01

    We examined changes in lipid profiles of 40 adult northern elephant seal bulls over the 3-month breeding fast and the 1-month molting fast to investigate impacts of fasting on serum total cholesterol (TC), triglycerides (TG) and lipoproteins. Total cholesterol and low-density lipoprotein (LDL) levels were initially high (3930 ± 190mgL(-1)and 1610 ± 170mgL(-1), respectively) and decreased significantly over the breeding season. Total cholesterol and LDL declined significantly with adipose tissue reserves (p<0.001), and LDL levels as low as 43 mgL(-1) were measured in seals late in the breeding fast. Less dramatic but similar changes in lipid metabolism were observed across the molting fast. High-density lipoproteins (HDL) remained consistently elevated (>1750 mgL(-1)) suggesting that elephant seals defend HDL concentrations, despite significant depletion of TC and LDL across the breeding fast. Triglyceride levels were significantly higher during the molt, consistent with lower rates of lipid oxidation needed to meet metabolic energy demands during this period. The maintenance of HDL during breeding is consistent with its role in delivering cholesterol from adipose tissue for steroidogenesis and spermatogenesis and potentially mitigates oxidative stress associated with fasting.

  9. The transport of low density lipoprotein-derived cholesterol to the plasma membrane is defective in NPC1 cells.

    PubMed

    Wojtanik, Kari M; Liscum, Laura

    2003-04-25

    Niemann-Pick disease type C (NPC) is characterized by lysosomal storage of cholesterol and gangliosides, which results from defects in intracellular lipid trafficking. Most studies of NPC1 have focused on its role in intracellular cholesterol movement. Our hypothesis is that NPC1 facilitates the egress of cholesterol from late endosomes, which are where active NPC1 is located. When NPC1 is defective, cholesterol does not exit late endosomes; instead, it is carried along to lysosomal storage bodies, where it accumulates. In this study, we addressed whether cholesterol is transported from endosomes to the plasma membrane before reaching NPC1-containing late endosomes. Our study was conducted in Chinese hamster ovary cell lines that display the classical NPC biochemical phenotype and belong to the NPC1 complementation group. We used three approaches to test whether low density lipoprotein (LDL)-derived cholesterol en route to NPC1-containing organelles passes through the plasma membrane. First, we used cyclodextrins to measure the arrival of LDL cholesterol at the plasma membrane and found that the arrival of LDL cholesterol in a cyclodextrin-accessible pool was significantly delayed in NPC1 cells. Second, the movement of LDL cholesterol to NPC1-containing late endosomes was assessed and found to be normal in Chinese hamster ovary mutant 3-6, which exhibits defective movement of plasma membrane cholesterol to intracellular membranes. Third, we examined the movement of plasma membrane cholesterol to the endoplasmic reticulum and found that this pathway is intact in NPC1 cells, i.e. it does not pass through NPC1-containing late endosomes. Our data suggest that in NPC1 cells LDL cholesterol traffics directly through endosomes to lysosomes, bypassing the plasma membrane, and is trapped there because of dysfunctional NPC1. PMID:12591922

  10. Preventing in-stent restenosis using lipoprotein (a), lipid and cholesterol adsorbent materials.

    PubMed

    Kazemian, Mohammad Reza; Solouk, Atefeh; Tan, Aaron; Seifalian, Alexander M

    2015-12-01

    Atherosclerosis is one of the major cause of mortality in developed countries. The characteristic lesion of atherosclerosis is the atheroma or plaque that forms through thickening of the inner layer of the vessel wall (called the intima). The development of stent in 1980s revolutionised treatment of cardiovascular diseases, including atherosclerosis. However the advent of stenting was hindered by the new problem of in-stent restenosis. It was demonstrated that in-stent restenosis was the result of a new pathology in the form of neointimal hyperplasia, which was a maladaptive healing response to bare-metal stent implantation. Recent evidence suggests that although drug-eluting stent (DES) have reduced restenosis rates, important concerns have been raised regarding increased late stent thrombosis, myocardial infarction and death. With advances in nanotechnology and smart materials, covered stents has been proposed to overcome this problem. This is due to in-stent late restenosis and thromboses are mainly caused by smooth muscle cells (SMC) proliferation. Studies showed that there is a relation between high low-density lipoprotein (LDL) and lipoprotein (a) [Lp(a)] level in blood stream and chance of in-stent restenosis, moreover studies show that Lp(a) could stimulate SMC proliferation. We hypothesis development of covered stent with novel design and use of smart materials which could adsorb cholesterol and prevent contact between Lp(a) and vessel wall to overcome problem indicated in DES. In addition cost of stents will significantly reduce by elimination of drugs as well as complex manufacturing of the drug incorporation. PMID:26364047

  11. Preventing in-stent restenosis using lipoprotein (a), lipid and cholesterol adsorbent materials.

    PubMed

    Kazemian, Mohammad Reza; Solouk, Atefeh; Tan, Aaron; Seifalian, Alexander M

    2015-12-01

    Atherosclerosis is one of the major cause of mortality in developed countries. The characteristic lesion of atherosclerosis is the atheroma or plaque that forms through thickening of the inner layer of the vessel wall (called the intima). The development of stent in 1980s revolutionised treatment of cardiovascular diseases, including atherosclerosis. However the advent of stenting was hindered by the new problem of in-stent restenosis. It was demonstrated that in-stent restenosis was the result of a new pathology in the form of neointimal hyperplasia, which was a maladaptive healing response to bare-metal stent implantation. Recent evidence suggests that although drug-eluting stent (DES) have reduced restenosis rates, important concerns have been raised regarding increased late stent thrombosis, myocardial infarction and death. With advances in nanotechnology and smart materials, covered stents has been proposed to overcome this problem. This is due to in-stent late restenosis and thromboses are mainly caused by smooth muscle cells (SMC) proliferation. Studies showed that there is a relation between high low-density lipoprotein (LDL) and lipoprotein (a) [Lp(a)] level in blood stream and chance of in-stent restenosis, moreover studies show that Lp(a) could stimulate SMC proliferation. We hypothesis development of covered stent with novel design and use of smart materials which could adsorb cholesterol and prevent contact between Lp(a) and vessel wall to overcome problem indicated in DES. In addition cost of stents will significantly reduce by elimination of drugs as well as complex manufacturing of the drug incorporation.

  12. Rapid on-line determination of cholesterol distribution among plasma lipoproteins after high-performance gel filtration chromatography.

    PubMed

    Kieft, K A; Bocan, T M; Krause, B R

    1991-05-01

    A high-performance gel chromatography (HPGC) system has been developed which allows the unattended on-line determination of lipoprotein cholesterol distribution (VLDL-C, LDL-C, HDL-C), within 40 min, in microliter quantities of plasma using a single, relatively inexpensive column (Superose 6HR). The FAST cholesterol reagent (Sclavo) and a knitted PFTE Kratos reaction coil (Applied Biosystems) were found to provide optimal sensitivity, linearity, resolution, and dispersion characteristics. Validation is provided by comparison to target values for human quality control reference sera, and by comparing the values obtained by HPGC to the beta-quant method (LRC). The utility of the system is illustrated by comparing profiles from seven different species with normal or elevated plasma cholesterol concentrations. This technique allows rapid analysis of samples, regardless of species, without the use of precipitating agents or the ultracentrifuge. It could also be applied for the direct clinical determination of LDL-cholesterol. PMID:2072044

  13. Proton pump inhibitors and statins: a possible interaction that favors low-density lipoprotein cholesterol reduction?

    PubMed Central

    Barkas, F; Elisaf, M; Rizos, CV; Klouras, E; Kostapanos, MS; Liberopoulos, E

    2015-01-01

    Background: Proton pump inhibitors (PPIs) might influence the metabolism of cholesterol and statins in the liver. Aim: The impact of PPIs on low-density lipoprotein cholesterol (LDL-C) levels in statin-treated patients. Methods: Retrospective observational study including consecutive statin-treated individuals followed for ≥3 years in a university hospital lipid clinic. Demographic characteristics as well as clinical and laboratory data were recorded at baseline and the most recent visit. High, moderate and low-intensity statin therapy was defined according to the expected LDL-C reduction (≥50%, 30-50%, and <30%, respectively). We compared the LDL-C reduction in subjects receiving statin + PPI with those on statin alone and assessed the overall effect of PPI administration on LDL-C lowering. Results: Of 648 statin-treated subjects, 7% were also taking a PPI. There was no difference between PPI vs. non-PPI group regarding baseline characteristics and intensity of lipid-lowering therapy. Stepwise linear regression analysis showed that PPI use was significantly associated with LDL-C reduction (b =0.104, p =0.005) along with baseline LDL-C levels (b =0.482, p <0.001), treatment with ezetimibe (b =0.198, p <0.001), presence of diabetes (b =0.168, p <0.001), compliance with treatment (b =0.205, p <0.001), intensity of statin treatment (b =0.101, p =0.005) and cardiovascular risk (b =0.082, p =0.049). Subjects receiving statin + PPI had a higher LDL-C reduction by 6.4% compared with those taking a statin alone (fully adjusted p =0.005). Conclusions: PPIs may modestly boost the statin-mediated LDL-C reduction. This effect should be confirmed by prospective clinical studies. Hippokratia 2015; 19 (4): 332-337.

  14. Intensive Lowering of Low-Density Lipoprotein Cholesterol Levels for Primary Prevention of Coronary Artery Disease

    PubMed Central

    Karalis, Dean G.

    2009-01-01

    Coronary artery disease (CAD) is the leading cause of morbidity and mortality in the United States, and a high concentration of low-density lipoprotein cholesterol (LDL-C) is a major risk factor for CAD. Current guidelines recommend the use of statins to lower LDL-C levels for the primary prevention of CAD based on an individual's risk factor profile and baseline LDL-C level. For moderaterisk individuals, those with 2 or more major risk factors for CAD and a Framingham risk score of 10% to 20%, the recommendation is to use a statin to lower LDL-C levels to less than 130 mg/dL. However, up to 40% of individuals who develop CAD have LDL-C levels lower than this cutoff. In 2004, the National Cholesterol Education Program Adult Treatment Panel III guidelines were updated to include an LDL-C goal of less than 100 mg/dL for individuals at moderately high risk of developing CAD. The guidelines identified several risk factors that when present would favor the use of pharmacological therapy to achieve this more aggressive LDL-C goal. This review evaluates the evidence supporting an LDL-C target of less than 100 mg/dL for moderately high-risk individuals and reviews those risk factors that when present help identify patients who would benefit from achieving this lower LDL-C goal. English-language publications in MEDLINE and references from relevant articles published between January 1, 1980, and November 30, 2008, were reviewed. Main keywords searched were coronary artery disease, hyperlipidemia, statins, cardiac risk factors, inflammatory markers, metabolic syndrome, and coronary artery calcium. PMID:19339653

  15. Increased hepatic cholesterol esterification with essential fatty acid deficiency (EFAD): relationship to plasma lipoprotein (LP) cholesterol content

    SciTech Connect

    Ney, D.M.; Ziboh, V.A.; Schneeman, B.O.

    1986-03-01

    EFAD in the rat is associated with hepatic accumulation of esterified cholesterol and altered distribution of cholesterol between plasma and hepatic tissue. Little is known regarding the impact of EFAD on LP composition. To determine the relationship between hepatic cholesterol esterification and plasma lP composition in control (C) and EFAD male Wistar rats, the authors induced EFAD with continuous intragastric (IG) infusion of EFA-free solutions containing 3.5% of calories as triolein for 7 and 14 days. C animals received IG infusion of solutions containing 3.5% of calories as linoleic acid. Data in the EFAD groups reveal: (i) marked decreases in hepatic EFAs and increases in monoenoic acids; (ii) progressive increases in hepatic content of triglyceride and esterified cholesterol with 7 and 14 days of feeding; (iii) assay of acyl CoA:cholesterol acyltransferase activity in hepatic tissue using /sup 14/C-cholesterol demonstrates an increase in hepatic cholesterol esterification when compared to C animals. Increased hepatic cholesterol esterification correlates with elevated levels of esterified cholesterol in plasma VLDL and HDL particles. These data indicate that the elevated levels of cholesterol esters in LP particles is due, at least in part, to increased hepatic cholesterol esterification with EFAD.

  16. Effect of the Probiotic Saccharomyces boulardii on Cholesterol and Lipoprotein Particles in Hypercholesterolemic Adults: A Single-Arm, Open-Label Pilot Study

    PubMed Central

    Hanes, Douglas Allen; Schafer, Morgan Beth; Mikolai, Jeremy; Zwickey, Heather

    2015-01-01

    Abstract Objectives: Elevated blood cholesterol levels are a major risk factor for coronary artery disease, the leading cause of death worldwide. Probiotics have been investigated as potential cholesterol-lowering therapies, but no previous studies have assessed the effect of the probiotic yeast Saccharomyces boulardii on cholesterol levels in human volunteers. The objective of this study was to examine the effect of S. boulardii on serum cholesterol and lipoprotein particles in hypercholesterolemic adults. Design: This study was a single-arm, open-label pilot study. Subjects: Twelve hypercholesterolemic participants were recruited into the study; one dropped out. Intervention: Participants took 5.6×1010 colony forming unit (CFU) encapsulated S. boulardii (Saccharomyces cerevisiae var. boulardii CNCM I-1079) twice daily for an 8-week period. Outcome measures: Fasting concentrations of cholesterol (total cholesterol, low-density lipoprotein-cholesterol [LDL-C], high-density lipoprotein-cholesterol [HDL-C], and triglycerides), lipoprotein particles (very-low-density lipoprotein-particle [VLDL-P], remnant lipoprotein particle [RLP-P], total LDL-P, LDL III-P, LDL IV-P, total HDL-P, and HDL 2b-P), and additional cardiovascular biomarkers (apo B-100, lipoprotein [a], high-sensitivity C-reactive protein, homocysteine, fibrinogen, and insulin) were measured at baseline, after 4 weeks, and after 8 weeks. Results: Remnant lipoprotein particles decreased by 15.5% (p=0.03) over the 8-week period. The remaining outcome measures were not significantly altered. Conclusions: In this pilot study, 8 weeks of daily supplementation with S. boulardii lowered remnant lipoprotein, a predictive biomarker and potential therapeutic target in the treatment and prevention of coronary artery disease. PMID:25893960

  17. High-density lipoprotein cholesterol is positively associated with hypertension in apparently healthy Japanese men and women.

    PubMed

    Oda, E; Kawai, R

    2011-01-01

    Among five components of metabolic syndrome, high-density lipoprotein (HDL) cholesterol is unique because it is not significantly associated with blood pressure. This study looks at cross-sectional relationships between HDL cholesterol and hypertension using medical check-up data from 1803 apparently healthy Japanese men aged 49.9 +/- 9.0 years, and 1150 Japanese women aged 49.5 +/- 9.0 years. Pearson's correlation coefficients between systolic blood pressure (SBP)/diastolic blood pressure (DBP) and HDL cholesterol were -0.01 (ns)/-0.01 (ns) in men and -0.04 (ns)/-0.01 (ns) in women. The standardised partial regression coefficient of HDL cholesterol for SBP/DBP (mmHg) controlling for age, body mass index (BMI), fasting plasma glucose (FPG), triglycerides, high-sensitivity C-reactive protein (hs-CRP) and low-density lipoprotein (LDL) cholesterol were 0.15 (P < 0.0001)/0.15 (P < 0.0001) in men and 0.10 (P < 0.0001)/0.12 (P < 0.0001) in women. The odds ratio (OR; 95% confidence interval [CI]) of a 1 mg/dL increment of HDL cholesterol for hypertension controlling for age, BMI, FPG, triglycerides, hs-CRP, LDL cholesterol, metabolic syndrome, diabetes, exercise status, drinking status, and smoking status was 1.03 (1.02-1.04; P < 0.001) in men and 1.03 (1.01-1.05; P = 0.002) in women. Thus, HDL cholesterol was independently positively associated with hypertension in apparently healthy Japanese men and women. PMID:21473259

  18. High-density lipoprotein cholesterol as an independent risk factor in cardiovascular disease: assessing the data from Framingham to the Veterans Affairs High--Density Lipoprotein Intervention Trial.

    PubMed

    Boden, W E

    2000-12-21

    The Framingham Heart Study found that high-density lipoprotein cholesterol (HDL-C) was the most potent lipid predictor of coronary artery disease risk in men and women >49 years of age. The Air Force/Texas Coronary Atherosclerosis Prevention Study (AFCAPS/TexCAPS), in which subjects were randomized to treatment with lovastatin or placebo, also reported a striking benefit of treatment, particularly in patients with HDL-C < or =35 mg/dL at baseline. Treatment with lovastatin was associated with a remarkable 45% reduction in events for this group. The Veterans Affairs HDL Intervention Trial (VA-HIT) randomized subjects to gemfibrozil or placebo. A high proportion of enrolled subjects with low HDL-C also had characteristics of the dysmetabolic syndrome. HDL-C likewise increased by 6% on treatment, total cholesterol was reduced by 4% and triglycerides by 31%. There was no change in low-density lipoprotein cholesterol (LDL-C) levels. These changes in lipid were associated with a cumulative 22% reduction in the trial primary endpoint of all-cause mortality and nonfatal myocardial infarction (MI). Additionally, significant reductions in secondary endpoints including death from coronary artery disease, nonfatal MI, stroke, transient ischemic attack, and carotid endarterectomy were associated with the increase in HDL-C. In VA-HIT, for every 1% increase in HDL-C, there was a 3% reduction in death or MI, a therapeutic benefit that eclipses the benefit associated with LDL-C reduction. PMID:11374850

  19. Association of lecithin-cholesterol acyltransferase activity measured as a serum cholesterol esterification rate and low-density lipoprotein heterogeneity with cardiovascular risk: a cross-sectional study.

    PubMed

    Tani, Shigemasa; Takahashi, Atsuhiko; Nagao, Ken; Hirayama, Atsushi

    2016-06-01

    The cholesterol-esterifying enzyme, lecithin-cholesterol acyltransferase (LCAT), is believed to play a key role in reverse cholesterol transport. However, recent investigations have demonstrated that higher LCAT activity levels increase the formation of triglyceride (TG)-rich lipoproteins (TRLs) and atherogenesis. We hypothesized that higher LCAT activity measured as a serum cholesterol esterification rate by the endogenous substrate method might increase the formation of TRLs and thereby alter low-density lipoprotein (LDL) heterogeneity. The estimated LDL particle size [relative LDL migration (LDL-Rm)] was measured by polyacrylamide gel electrophoresis with the LipoPhor system (Joko, Tokyo, Japan) in 538 consecutive patients with at least risk factor for atherosclerosis. Multivariate regression analysis after adjustments for traditional risk factors identified elevated TRL-related marker (TG, remnant-like particle cholesterol, apolipoprotein C-II, and apolipoprotein C-III) levels as independent predictors of smaller-sized LDL particle size, both in the overall subject population and in the subset of patients with serum LDL cholesterol levels of <100 mg/dL. Area under the receiver operating characteristic curve of the LCAT activity (0.79; sensitivity 60 %; specificity 84.8 %) was observed for the evaluation of the indicators of an LDL-Rm value of ≥0.40, which suggests the presence of large amounts of small-dense LDL. The results lend support to the hypothesis that increased LCAT activity may be associated with increased formation of TRLs, leading to a reduction in LDL particle size. Therefore, to reduce the risk of atherosclerotic cardiovascular disease, it may be of importance to pay attention not only to a quantitative change in the serum LDL-C, but also to the LCAT activity which is possibly associated with LDL heterogeneity. PMID:25894629

  20. An in-silico model of lipoprotein metabolism and kinetics for the evaluation of targets and biomarkers in the reverse cholesterol transport pathway.

    PubMed

    Lu, James; Hübner, Katrin; Nanjee, M Nazeem; Brinton, Eliot A; Mazer, Norman A

    2014-03-01

    High-density lipoprotein (HDL) is believed to play an important role in lowering cardiovascular disease (CVD) risk by mediating the process of reverse cholesterol transport (RCT). Via RCT, excess cholesterol from peripheral tissues is carried back to the liver and hence should lead to the reduction of atherosclerotic plaques. The recent failures of HDL-cholesterol (HDL-C) raising therapies have initiated a re-examination of the link between CVD risk and the rate of RCT, and have brought into question whether all target modulations that raise HDL-C would be atheroprotective. To help address these issues, a novel in-silico model has been built to incorporate modern concepts of HDL biology, including: the geometric structure of HDL linking the core radius with the number of ApoA-I molecules on it, and the regeneration of lipid-poor ApoA-I from spherical HDL due to remodeling processes. The ODE model has been calibrated using data from the literature and validated by simulating additional experiments not used in the calibration. Using a virtual population, we show that the model provides possible explanations for a number of well-known relationships in cholesterol metabolism, including the epidemiological relationship between HDL-C and CVD risk and the correlations between some HDL-related lipoprotein markers. In particular, the model has been used to explore two HDL-C raising target modulations, Cholesteryl Ester Transfer Protein (CETP) inhibition and ATP-binding cassette transporter member 1 (ABCA1) up-regulation. It predicts that while CETP inhibition would not result in an increased RCT rate, ABCA1 up-regulation should increase both HDL-C and RCT rate. Furthermore, the model predicts the two target modulations result in distinct changes in the lipoprotein measures. Finally, the model also allows for an evaluation of two candidate biomarkers for in-vivo whole-body ABCA1 activity: the absolute concentration and the % lipid-poor ApoA-I. These findings illustrate the

  1. An in-silico model of lipoprotein metabolism and kinetics for the evaluation of targets and biomarkers in the reverse cholesterol transport pathway.

    PubMed

    Lu, James; Hübner, Katrin; Nanjee, M Nazeem; Brinton, Eliot A; Mazer, Norman A

    2014-03-01

    High-density lipoprotein (HDL) is believed to play an important role in lowering cardiovascular disease (CVD) risk by mediating the process of reverse cholesterol transport (RCT). Via RCT, excess cholesterol from peripheral tissues is carried back to the liver and hence should lead to the reduction of atherosclerotic plaques. The recent failures of HDL-cholesterol (HDL-C) raising therapies have initiated a re-examination of the link between CVD risk and the rate of RCT, and have brought into question whether all target modulations that raise HDL-C would be atheroprotective. To help address these issues, a novel in-silico model has been built to incorporate modern concepts of HDL biology, including: the geometric structure of HDL linking the core radius with the number of ApoA-I molecules on it, and the regeneration of lipid-poor ApoA-I from spherical HDL due to remodeling processes. The ODE model has been calibrated using data from the literature and validated by simulating additional experiments not used in the calibration. Using a virtual population, we show that the model provides possible explanations for a number of well-known relationships in cholesterol metabolism, including the epidemiological relationship between HDL-C and CVD risk and the correlations between some HDL-related lipoprotein markers. In particular, the model has been used to explore two HDL-C raising target modulations, Cholesteryl Ester Transfer Protein (CETP) inhibition and ATP-binding cassette transporter member 1 (ABCA1) up-regulation. It predicts that while CETP inhibition would not result in an increased RCT rate, ABCA1 up-regulation should increase both HDL-C and RCT rate. Furthermore, the model predicts the two target modulations result in distinct changes in the lipoprotein measures. Finally, the model also allows for an evaluation of two candidate biomarkers for in-vivo whole-body ABCA1 activity: the absolute concentration and the % lipid-poor ApoA-I. These findings illustrate the

  2. Influence of infant and juvenile diets on serum cholesterol, lipoprotein cholesterol, and apolipoprotein concentrations in juvenile baboons (Papio sp.).

    PubMed

    Mott, G E; McMahan, C A; Kelley, J L; Farley, C M; McGill, H C

    1982-11-01

    The long-term effects of infant diet (breast milk or formula containing 2, 30, or 60 mg/dl cholesterol) and subsequent dietary cholesterol (1 mg/kcal) and fat (saturated or unsaturated) on serum lipid and apolipoprotein concentrations were estimated using 82 juvenile baboons 4-6 years of age. A significant interaction of infant diet (breast vs formula) with type of fat (saturated vs unsaturated) at 4-6 years of age was observed on HDL cholesterol and apolipoprotein A-I (apoA-I) concentrations. That is, animals breast-fed as infants had higher HDL cholesterol and apoA-I concentrations when fed unsaturated fat from weaning to 4-6 years of age than those fed saturated fat (77 vs 68 mg/dl). In contrast, animals fed formulas in infancy followed by a diet containing unsaturated fat had lower HDL cholesterol and apoA-I concentrations at 4-6 years of age than did those fed saturated fat (67 vs 78 mg/dl). However, breast feeding or feeding formulas containing various levels of cholesterol for 3 months during infancy did not result in statistically significant differences in total serum cholesterol, VLDL + LDL cholesterol and apolipoprotein B (apoB) concentrations. Dietary cholesterol after infancy significantly increased serum total cholesterol, VLDL + LDL and HDL cholesterol, apoA-I and apoB concentrations. All of these response variables also were higher in animals fed saturated fat compared to those fed unsaturated fat on the same level of cholesterol. At 4-6 years of age, regardless of diet, females had significantly higher serum VLDL + LDL cholesterol (57 vs 43 mg/dl) and apoB concentrations (39 vs 30 mg/dl) than did males.

  3. Relative efficacy of antilipemic agents in non–high-density lipoprotein cholesterol reduction.

    PubMed

    Santee, Jennifer; Lindsey, Cameron; Pace, Heather

    2012-08-01

    The investigators sought to summarize the percentage reduction in non–high-density lipoprotein cholesterol (non-HDL-C) achieved with various antilipemic regimens and to determine whether certain antilipemic regimens have been proven more effective in lowering non-HDL-C. A search of MEDLINE, International Pharmaceutical Abstracts, and Iowa Drug Information Service Database from 1970 to May 2011 was performed. Criteria were used to exclude studies not published in English, studies with methodology limitations, and studies with variables that may affect efficacy beyond the antilipemic agent administered. Only randomized, controlled trials comparing medications approved by the Food and Drug Administration were reviewed to determine whether significant differences in percentage reduction in non-HDL-C had been observed between different medication regimens. A total of 51 trials reported data that could be used to determine the range of percentage reduction in non-HDL-C achieved by select antilipemic regimens. Of these 51 trials, 38 provided head-to-head comparisons of antilipemic regimens. Rosuvastatin and atorvastatin are the most potent 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) in lowering non-HDL-C. Adding ezetimibe, fibric acid derivatives, and omega-3 fatty acids to antilipemic monotherapy may result in further reduction in non-HDL-C. Subjects with certain characteristics (eg, nonwhite) were not prevalent in these studies. PMID:22551562

  4. How Do PCSK9 Inhibitors Stack Up to Statins for Low-Density Lipoprotein Cholesterol Control?

    PubMed Central

    Zimmerman, Marj P.

    2015-01-01

    Despite advances in the approach toward treating hypercholesterolemia and widespread access to statin medications, not all people are able to reach target low-density lipoprotein cholesterol (LDL-C) levels to reduce their cardiovascular risk. Some of the reasons include the inability to tolerate statin therapy, LDL-C levels that remain high even in the presence of statin therapy, and a familial disorder that is characterized by extremely high levels of LDL-C. A new therapeutic class, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, represents a novel and promising approach to reducing LDL-C levels using a mechanism at the LDL receptor level. The recent approval of the first 2 PCSK9 inhibitors and the anticipated approval of the third agent in this class within approximately 1 year may provide clinicians powerful new weapons to lower LDL-C levels in patients who are not satisfactorily managed with statins. However, the results of long-term studies of the ability of these new medications to influence cardiovascular outcomes will not be known for several years. PMID:26702335

  5. Clinical efficacy and safety of evolocumab for low-density lipoprotein cholesterol reduction.

    PubMed

    Henry, Courtney A; Lyon, Ronald A; Ling, Hua

    2016-01-01

    Multiple categories of medications have been developed to manage lipid profiles and reduce the risk of cardiovascular events in patients with heart disease. However, currently marketed medications have not solved the problems associated with preventing and treating cardiovascular diseases completely. A substantial population of patients cannot take advantage of statin therapy due to statin intolerance, heart failure, or kidney hemodialysis, suggesting a need for additional effective agents to reduce low-density lipoprotein cholesterol (LDL-C) levels. Proprotein convertase subtilisin/kexin type 9 (PCSK9) was discovered in 2003 and subsequently emerged as a novel target for LDL-C-lowering therapy. Evolocumab is a fully human monoclonal immunoglobulin G2 (IgG2) directed against human PCSK9. By inactivating PCSK9, evolocumab upregulates LDL receptors causing increased catabolism of LDL-C and the consequent reduction of LDL-C levels in blood. Overall, evolocumab has had notable efficacy, with LDL-C reduction ranging from 53% to 75% in monotherapy and combination therapies, and is associated with minor adverse effects. However, studies regarding the ability of evolocumab to reduce mortality as well as long-term safety concerns are limited. The fact that the drug was introduced at a cost much higher than the existing medications and shows a low incremental mortality benefit suggests that many payers will consider evolocumab to have an unfavorable cost-benefit ratio.

  6. How Do PCSK9 Inhibitors Stack Up to Statins for Low-Density Lipoprotein Cholesterol Control?

    PubMed

    Zimmerman, Marj P

    2015-11-01

    Despite advances in the approach toward treating hypercholesterolemia and widespread access to statin medications, not all people are able to reach target low-density lipoprotein cholesterol (LDL-C) levels to reduce their cardiovascular risk. Some of the reasons include the inability to tolerate statin therapy, LDL-C levels that remain high even in the presence of statin therapy, and a familial disorder that is characterized by extremely high levels of LDL-C. A new therapeutic class, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, represents a novel and promising approach to reducing LDL-C levels using a mechanism at the LDL receptor level. The recent approval of the first 2 PCSK9 inhibitors and the anticipated approval of the third agent in this class within approximately 1 year may provide clinicians powerful new weapons to lower LDL-C levels in patients who are not satisfactorily managed with statins. However, the results of long-term studies of the ability of these new medications to influence cardiovascular outcomes will not be known for several years. PMID:26702335

  7. Reduction of low-density lipoprotein cholesterol by monoclonal antibody inhibition of PCSK9.

    PubMed

    Stein, Evan A; Raal, Frederick

    2014-01-01

    Published phase I and II trials with two fully human monoclonal antibodies to PCSK9 have provided comprehensive evidence that inhibiting PCSK9 is a very effective method to reduce low-density lipoprotein cholesterol (LDL-C). In all populations studied so far, whether on statins or LDL-C-reducing diet alone, with or without a genetic defect in the LDL receptor, and in subjects intolerant to statins, the LDL-C reductions have been large and consistent. Even the most efficacious statin, rosuvastatin, at its highest dose has not achieved such reductions. The clinical trials have established that monoclonal antibody therapy targeted to PCSK9 may be administered subcutaneously every two or four weeks. Current data suggest these drugs will provide an effective therapeutic option for LDL-C reduction and that, if proven safe in phase III trials, they will be as important to LDL-C control, and likely to cardiovascular disease risk reduction, as statins have been over the past three decades. PMID:24422577

  8. Clinical efficacy and safety of evolocumab for low-density lipoprotein cholesterol reduction

    PubMed Central

    Henry, Courtney A; Lyon, Ronald A; Ling, Hua

    2016-01-01

    Multiple categories of medications have been developed to manage lipid profiles and reduce the risk of cardiovascular events in patients with heart disease. However, currently marketed medications have not solved the problems associated with preventing and treating cardiovascular diseases completely. A substantial population of patients cannot take advantage of statin therapy due to statin intolerance, heart failure, or kidney hemodialysis, suggesting a need for additional effective agents to reduce low-density lipoprotein cholesterol (LDL-C) levels. Proprotein convertase subtilisin/kexin type 9 (PCSK9) was discovered in 2003 and subsequently emerged as a novel target for LDL-C-lowering therapy. Evolocumab is a fully human monoclonal immunoglobulin G2 (IgG2) directed against human PCSK9. By inactivating PCSK9, evolocumab upregulates LDL receptors causing increased catabolism of LDL-C and the consequent reduction of LDL-C levels in blood. Overall, evolocumab has had notable efficacy, with LDL-C reduction ranging from 53% to 75% in monotherapy and combination therapies, and is associated with minor adverse effects. However, studies regarding the ability of evolocumab to reduce mortality as well as long-term safety concerns are limited. The fact that the drug was introduced at a cost much higher than the existing medications and shows a low incremental mortality benefit suggests that many payers will consider evolocumab to have an unfavorable cost–benefit ratio. PMID:27143910

  9. Clinical efficacy and safety of evolocumab for low-density lipoprotein cholesterol reduction.

    PubMed

    Henry, Courtney A; Lyon, Ronald A; Ling, Hua

    2016-01-01

    Multiple categories of medications have been developed to manage lipid profiles and reduce the risk of cardiovascular events in patients with heart disease. However, currently marketed medications have not solved the problems associated with preventing and treating cardiovascular diseases completely. A substantial population of patients cannot take advantage of statin therapy due to statin intolerance, heart failure, or kidney hemodialysis, suggesting a need for additional effective agents to reduce low-density lipoprotein cholesterol (LDL-C) levels. Proprotein convertase subtilisin/kexin type 9 (PCSK9) was discovered in 2003 and subsequently emerged as a novel target for LDL-C-lowering therapy. Evolocumab is a fully human monoclonal immunoglobulin G2 (IgG2) directed against human PCSK9. By inactivating PCSK9, evolocumab upregulates LDL receptors causing increased catabolism of LDL-C and the consequent reduction of LDL-C levels in blood. Overall, evolocumab has had notable efficacy, with LDL-C reduction ranging from 53% to 75% in monotherapy and combination therapies, and is associated with minor adverse effects. However, studies regarding the ability of evolocumab to reduce mortality as well as long-term safety concerns are limited. The fact that the drug was introduced at a cost much higher than the existing medications and shows a low incremental mortality benefit suggests that many payers will consider evolocumab to have an unfavorable cost-benefit ratio. PMID:27143910

  10. Alpinia zerumbet potentially elevates high-density lipoprotein cholesterol level in hamsters.

    PubMed

    Lin, Li-Yun; Peng, Chiung-Chi; Liang, Yu-Jing; Yeh, Wan-Ting; Wang, Hui-Er; Yu, Tung-Hsi; Peng, Robert Y

    2008-06-25

    In folkloric plant medicines, Alpinia zerumbet (AZ) has been popularly recognized as an exellent hepatoprotector. To search for a good high-density lipoprotein cholesterol (HDL-C) elevating herbal preparation, we examined AZ for its antioxidant and hypolipidaemic bioactivities, especially its HDL-C elevating activity. AZ seeds contain 0.51% essential oils (SO), which are comprised of monoterpenoids, oxygenated monoterpenoids, sesquiterpenoids, oxygenated sesquiterpenoids, aldehydes, acid, and esters. Gas chromatography/mass spectrometry analysis indicated that most of the monoterpenes and sesquiterpenes were recoverable in pentane eluent, whilst the oxygenated monoterpenoids and sesquiterpenoids remained in ether eluent. The high contents of rutin, quercetin, and polyphenolics in ethanolic extract of AZ seeds exhibit moderate antilipoperoxidative but potent DPPH free radical scavenging bioactivities. Conclusively, both seed powder (SP) and SO are effective hypolipidaemics with amazingly potent HDL-C elevating capabilities. On the basis of hepatoprotectivity, SP is a more feasible hypolipidemic agent as well as a promising HDL-C elevating plant medicine.

  11. Dietary Squalene Increases High Density Lipoprotein-Cholesterol and Paraoxonase 1 and Decreases Oxidative Stress in Mice

    PubMed Central

    Gabás-Rivera, Clara; Barranquero, Cristina; Martínez-Beamonte, Roberto; Navarro, María A.; Surra, Joaquín C.; Osada, Jesús

    2014-01-01

    Background and Purpose Squalene, the main hydrocarbon in the unsaponifiable fraction of virgin olive oil, is involved in cholesterol synthesis and it has been reported to own antiatherosclerotic and antiesteatosic effects. However, the squalene's role on lipid plasma parameters and the influence of genotype on this effect need to be addressed. Experimental Approaches Three male mouse models (wild-type, Apoa1- and Apoe- deficient) were fed chow semisynthetic diets enriched in squalene to provide a dose of 1 g/kg during 11 weeks. After this period, their plasma parameters and lipoprotein profiles were analyzed. Key Results Squalene administration at a dose of 1 g/kg showed decreased reactive oxygen species in lipoprotein fractions independently of the animal background and caused an specific increase in high density lipoprotein (HDL)-cholesterol levels, accompanied by an increase in phosphatidylcholine and paraoxonase 1 and no changes in apolipoproteins A1 and A4 in wild-type mice. In these mice, the cholesterol increase was due to its esterified form and associated with an increased hepatic expression of Lcat. These effects were not observed in absence of apolipoprotein A1. The increases in HDL- paraoxonase 1 were translated into decreased plasma malondialdehyde levels depending on the presence of Apolipoprotein A1. Conclusions and Implications Dietary squalene promotes changes in HDL- cholesterol and paraoxonase 1 and decreases reactive oxygen species in lipoproteins and plasma malondialdehyde levels, providing new benefits of its intake that might contribute to explain the properties of virgin olive oil, although the phenotype related to apolipoproteins A1 and E may be particularly relevant. PMID:25117703

  12. Lipoprotein(a) particle concentration and lipoprotein(a) cholesterol assays yield discordant classification of patients into four physiologically discrete groups.

    PubMed

    Konerman, Matthew; Kulkarni, Krishnaji; Toth, Peter P; Jones, Steven R

    2012-01-01

    There is little known about the relative predictive value of different lipoprotein(a) [Lp(a)] assays in clinical use, although each has been shown to predict similar incremental risk over conventional clinical and lipid risk factors. Thus, we examined the classification behavior of two commonly used Lp(a) assays and their associations with other lipid parameters. Serum lipid and Lp(a) concentrations were measured in 144 primary and secondary prevention patients. Lp(a) cholesterol [Lp(a)-C] was measured with the Vertical Auto Profile (upper limit of normal, 10 mg/dL). Lp(a) particle concentrations [Lp(a)-P] were measured with an isoform-independent molar assay (upper limit of normal, 70 nmol/L). The subjects were divided into the following four groups on the basis of their Lp(a)-C and Lp(a)-P levels: normal Lp(a)-P and Lp(a)-C; high Lp(a)-P and normal Lp(a)-C; normal Lp(a)-P and high Lp(a)-C; and high Lp(a)-P and Lp(a)-C. The proportion of subjects with values above the upper limit of normal was similar with both assays (P = .15). However, the Lp(a)-C and Lp(a)-P assays discordantly classified 23% of the study's subjects. In addition, the four Lp(a)-defined groups displayed differences in their relationships with other lipoproteins. The two groups with elevated Lp(a)-C showed significant associations with higher high-density lipoprotein cholesterol, apolipoprotein AI, and high-density lipoprotein cholesterol/apolipoprotein AI ratios. Triglycerides were also noted to be above normal in discordant and normal within concordant Lp(a) groups. Finally, the amount of cholesterol per Lp(a) particle [Lp(a)-C/Lp(a)-P] varied widely across the four groups. These findings suggest that the four Lp(a)-defined groups are physiologically discrete. Further investigation is warranted to assess which parameters among Lp(a)-P, Lp(a)-C, and Lp(a)-C/Lp(a)-P can be used to more accurately characterize Lp(a)-associated cardiovascular risk. PMID:22836074

  13. Non-High-Density Lipoprotein Cholesterol in Children with Diabetes: Proposed Treatment Recommendations Based on Glycemic Control, Body Mass Index, Age, Sex, and Generally Accepted Cut Points.

    PubMed

    Schwab, K Otfried; Doerfer, Jürgen; Hungele, Andreas; Scheuing, Nicole; Krebs, Andreas; Dost, Axel; Rohrer, Tilman R; Hofer, Sabine; Holl, Reinhard W

    2015-12-01

    Percentile-based non-high-density lipoprotein cholesterol levels were analyzed by glycemic control, weight, age, and sex of children with type 1 diabetes (n = 26,358). Ten percent of all children and 25% of overweight adolescent girls require both immediate lipid-lowering medication and lifestyle changes to achieve non-high-density lipoprotein cholesterol levels <120 mg/dL and cardiovascular risk reduction.

  14. Modulators of Hepatic Lipoprotein Metabolism Identified in a Search for Small-Molecule Inducers of Tribbles Pseudokinase 1 Expression

    PubMed Central

    Nagiec, Marek M.; Skepner, Adam P.; Negri, Joseph; Eichhorn, Michelle; Kuperwasser, Nicolas; Comer, Eamon; Muncipinto, Giovanni; Subramanian, Aravind; Clish, Clary; Musunuru, Kiran; Duvall, Jeremy R.; Foley, Michael; Perez, Jose R.; Palmer, Michelle A. J.

    2015-01-01

    Recent genome wide association studies have linked tribbles pseudokinase 1 (TRIB1) to the risk of coronary artery disease (CAD). Based on the observations that increased expression of TRIB1 reduces secretion of VLDL and is associated with lower plasma levels of LDL cholesterol and triglycerides, higher plasma levels of HDL cholesterol and reduced risk for myocardial infarction, we carried out a high throughput phenotypic screen based on quantitative RT-PCR assay to identify compounds that induce TRIB1 expression in human HepG2 hepatoma cells. In a screen of a collection of diversity-oriented synthesis (DOS)-derived compounds, we identified a series of benzofuran-based compounds that upregulate TRIB1 expression and phenocopy the effects of TRIB1 cDNA overexpression, as they inhibit triglyceride synthesis and apoB secretion in cells. In addition, the compounds downregulate expression of MTTP and APOC3, key components of the lipoprotein assembly pathway. However, CRISPR-Cas9 induced chromosomal disruption of the TRIB1 locus in HepG2 cells, while confirming its regulatory role in lipoprotein metabolism, demonstrated that the effects of benzofurans persist in TRIB1-null cells indicating that TRIB1 is sufficient but not necessary to transmit the effects of the drug. Remarkably, active benzofurans, as well as natural products capable of TRIB1 upregulation, also modulate hepatic cell cholesterol metabolism by elevating the expression of LDLR transcript and LDL receptor protein, while reducing the levels of PCSK9 transcript and secreted PCSK9 protein and stimulating LDL uptake. The effects of benzofurans are not masked by cholesterol depletion and are independent of the SREBP-2 regulatory circuit, indicating that these compounds represent a novel class of chemically tractable small-molecule modulators that shift cellular lipoprotein metabolism in HepG2 cells from lipogenesis to scavenging. PMID:25811180

  15. Elevated High-Density Lipoprotein Cholesterol and Age-Related Macular Degeneration: The Alienor Study

    PubMed Central

    Cougnard-Grégoire, Audrey; Delyfer, Marie-Noëlle; Korobelnik, Jean-François; Rougier, Marie-Bénédicte; Le Goff, Mélanie; Dartigues, Jean-François; Barberger-Gateau, Pascale; Delcourt, Cécile

    2014-01-01

    Background Lipid metabolism and particularly high-density lipoprotein (HDL) may be involved in the pathogenic mechanism of age-related macular degeneration (AMD). However, conflicting results have been reported in the associations of AMD with plasma HDL and other lipids, which may be confounded by the recently reported associations of AMD with HDL-related genes. We explored the association of AMD with plasma lipid levels and lipid-lowering medication use, taking into account most of HDL-related genes associated with AMD. Methods The Alienor study is a population-based study on age-related eye diseases performed in 963 elderly residents of Bordeaux (France). AMD was graded from non mydriatic color retinal photographs in three exclusive stages: no AMD (n = 430 subjects, 938 eyes); large soft distinct drusen and/or large soft indistinct drusen and/or reticular drusen and/or pigmentary abnormalities (early AMD, n = 176, 247); late AMD (n = 40, 61). Associations of AMD with plasma lipids (HDL, total cholesterol (TC), Low-density lipoprotein (LDL), and triglycerides (TG)) were estimated using Generalized Estimating Equation logistic regressions. Statistical analyses included 646 subjects with complete data. Results After multivariate adjustment for age, sex, educational level, smoking, BMI, lipid-lowering medication use, cardiovascular disease and diabetes, and for all relevant genetic polymorphisms (ApoE2, ApoE4, CFH Y402H, ARMS2 A69S, LIPC rs10468017, LIPC rs493258, LPL rs12678919, ABCA1 rs1883025 and CETP rs3764261), higher HDL was significantly associated with an increased risk of early (OR = 2.45, 95%CI: 1.54–3.90; P = 0.0002) and any AMD (OR = 2.29, 95%CI: 1.46–3.59; P = 0.0003). Association with late AMD was far from statistical significance (OR = 1.58, 95%CI: 0.48–5.17; p = 0.45). No associations were found for any stage of AMD with TC, LDL and TG levels, statin or fibrate drug use. Conclusions This study suggests that

  16. Candidate genetic analysis of plasma high-density lipoprotein-cholesterol and severity of coronary atherosclerosis

    PubMed Central

    Chen, Suet Nee; Cilingiroglu, Mehmet; Todd, Josh; Lombardi, Raffaella; Willerson, James T; Gotto, Antonio M; Ballantyne, Christie M; Marian, AJ

    2009-01-01

    Background Plasma level of high-density lipoprotein-cholesterol (HDL-C), a heritable trait, is an important determinant of susceptibility to atherosclerosis. Non-synonymous and regulatory single nucleotide polymorphisms (SNPs) in genes implicated in HDL-C synthesis and metabolism are likely to influence plasma HDL-C, apolipoprotein A-I (apo A-I) levels and severity of coronary atherosclerosis. Methods We genotyped 784 unrelated Caucasian individuals from two sets of populations (Lipoprotein and Coronary Atherosclerosis Study- LCAS, N = 333 and TexGen, N = 451) for 94 SNPs in 42 candidate genes by 5' nuclease assays. We tested the distribution of the phenotypes by the Shapiro-Wilk normality test. We used Box-Cox regression to analyze associations of the non-normally distributed phenotypes (plasma HDL-C and apo A-I levels) with the genotypes. We included sex, age, body mass index (BMI), diabetes mellitus (DM), and cigarette smoking as covariates. We calculated the q values as indicators of the false positive discovery rate (FDR). Results Plasma HDL-C levels were associated with sex (higher in females), BMI (inversely), smoking (lower in smokers), DM (lower in those with DM) and SNPs in APOA5, APOC2, CETP, LPL and LIPC (each q ≤0.01). Likewise, plasma apo A-I levels, available in the LCAS subset, were associated with SNPs in CETP, APOA5, and APOC2 as well as with BMI, sex and age (all q values ≤0.03). The APOA5 variant S19W was also associated with minimal lumen diameter (MLD) of coronary atherosclerotic lesions, a quantitative index of severity of coronary atherosclerosis (q = 0.018); mean number of coronary artery occlusions (p = 0.034) at the baseline and progression of coronary atherosclerosis, as indicated by the loss of MLD. Conclusion Putatively functional variants of APOA2, APOA5, APOC2, CETP, LPL, LIPC and SOAT2 are independent genetic determinants of plasma HDL-C levels. The non-synonymous S19W SNP in APOA5 is also an independent determinant of plasma

  17. Alpinetin enhances cholesterol efflux and inhibits lipid accumulation in oxidized low-density lipoprotein-loaded human macrophages.

    PubMed

    Jiang, Zhengming; Sang, Haiqiang; Fu, Xin; Liang, Ying; Li, Ling

    2015-01-01

    Alpinetin is a natural flavonoid abundantly present in the ginger family. Here, we investigated the effect of alpinetin on cholesterol efflux and lipid accumulation in oxidized low-density lipoprotein (ox-LDL)-treated THP-1 macrophages and human peripheral blood monocyte-derived macrophages (HMDMs). After exposing THP-1 macrophages to alpinetin, cholesterol efflux was determined by liquid scintillator. The mRNA and protein levels of peroxisome proliferator-activated receptor gamma (PPAR-γ), liver X receptor alpha (LXR-α), ATP-binding cassette transporter A1 (ABCA1), and ABCG1 and scavenger receptor class B member 1 were determined by reverse-transcriptase PCR (RT-PCR) and Western blot analysis, respectively. Alpinetin promoted apolipoprotein A-I- and high-density-lipoprotein-mediated cholesterol efflux and elevated PPAR-γ and LXR-α mRNA and protein expression in a dose-dependent fashion in ox-LDL-treated THP-1 macrophages and HMDMs. Small interfering RNA-mediated silencing of PPAR-γ or LXR-α dose dependently reversed alpinetin-increased cholesterol efflux in THP-1 macrophages, indicating the involvement of PPAR-γ and LXR-α in alpinetin-promoted cholesterol efflux. Alpinetin inhibited ox-LDL-induced lipid accumulation and enhanced the expression of ABCA1 and ABCG1 mRNA and protein, which was reversed by specific knockdown of PPAR-γ or LXR-α. Taken together, our results reveal that alpinetin exhibits positive effects on cholesterol efflux and inhibits ox-LDL-induced lipid accumulation, which might be through PPAR-γ/LXR-α/ABCA1/ABCG1 pathway.

  18. Roles of High-Density Lipoprotein Cholesterol in Patients With Acute Myocardial Infarction.

    PubMed

    Lee, Cheol Hyun; Woo, Jong Shin; Park, Chang Bum; Cho, Jin Man; Ahn, Young Keun; Kim, Chong Jin; Jeong, Myung Ho; Kim, Weon

    2016-05-01

    Many observational studies showed hogh-density lipoprotein cholesterol (HDL-C) is a strong inverse predictor of cardiovascular (CV) outcome. However, recent large clinical trials evaluating therapies to raise HDL-C level in those already on statin therapy have been discouraging. This complexity is not well-known.A total of 28,357 acute myocardial infarction (AMI) patients were enrolled in the Korea Acute Myocardial Infarction Registry (KAMIR), which was a prospective, multicenter, nationwide, web-based database of AMI in Korea. From this registry, we evaluated 3574 patients with AMI who have follow-up HDL-C level to investigate its association with clinical outcomes. The primary endpoint was the relationship between follow-up change in HDL-C and a 12-month composite of major adverse cardiac events (MACEs).Patients with initial HDL-C ≥ 40 mg/dL showed significantly lower rates of 12-month MACEs, especially cardiac and all-cause mortalities (P < 0.001). When patients were stratified into 4 groups according to the change of HDL-C, patients with decreasing HDL-C showed significantly higher rates of 12-month MACEs as comparable with patients with increasing HLD-C. A multivariate analysis indicated that HDL-C level was a significant predictor of CV events (hazard ratio, 1.38; 95% confidence interval, 1.12-1.71) after correcting for confounding variables.The follow-up change in HDL-C level was significantly related with CV outcomes in patients with AMI. PMID:27149442

  19. Vitamin D Supplementation and High-Density Lipoprotein Cholesterol: A Study in Healthy School Children

    PubMed Central

    Tavakoli, Fatemeh; Namakin, Kokab; Zardast, Mahmood

    2016-01-01

    Background The high-density lipoprotein cholesterol (HDL-C) level has been shown to have a significant role in the prevention of cardiovascular diseases and atherosclerosis. Low vitamin D levels have been shown to be correlated with dyslipidemia, but limited data exist on indigenous children. Objectives We aimed to investigate the effect of vitamin D supplementation on HDL-C levels in school-aged Iranian children. Methods In this prospective controlled clinical trial, 47 healthy children (23 boys) aged 10 - 14 years, students of Birjand (Iran) elementary schools, were selected and randomly divided into two groups. The study group received a vitamin D supplement (1000 mg capsule) daily for one month, and placebo tablets were prescribed to the controls. Before and after the treatment course, the serum HDL-C and 25-hydroxy vitamin D levels of both groups were measured. The data were analyzed by SPSS, ver. 16, and Chi-square tests, Fisher’s exact test, paired-sample t-tests, and Pearson’s correlation were used, wherever appropriate. The significance level was set at P < 0.05. Results Forty children completed the study; their mean age was 11.5 ± 1.175 years. The mean serum levels of both HDL-C and vitamin D showed a significant rise following the treatment in the study group (P = 0.007 and P < 0.001, respectively), whereas both variables decreased slightly in the control group (P = 0.27). There was no statistically significant difference in the mean serum levels of HDL-C and vitamin D between the two groups after the intervention (P = 0.11 and P = 0.20, respectively). Conclusions Vitamin D supplements seem to have a positive impact on serum HDL-C levels and may be effective in reducing the risk of cardiovascular diseases in the long term. PMID:27713805

  20. Reduction in Postoperative High-Density Lipoprotein Cholesterol Levels in Children Undergoing the Fontan Operation

    PubMed Central

    Argraves, W. Scott; Graham, Eric M.; Slate, Elizabeth H.; Atz, Andrew M.; Bradley, Scott M.; McQuinn, Tim C.; Wilkerson, Brent A.; Wing, Shane B.

    2015-01-01

    Despite the emerging relevance of high-density lipoprotein (HDL) in the inflammatory cascade and vascular barrier integrity, HDL levels in children undergoing cardiac surgery are unexplored. As a measure of HDL levels, the HDL-cholesterol (HDL-C) in single-ventricle patients was quantified before and after the Fontan operation, and it was determined whether relationships existed between the duration and the type of postoperative pleural effusions. The study prospectively enrolled 12 children undergoing the Fontan operation. Plasma HDL-C levels were measured before and after cardiopulmonary bypass. The outcome variables of interest were the duration and type of chest tube drainage (chylous vs. nonchylous). The Kendall rank correlation coefficient and the Wilcoxon rank sum test were used. There were 11 complete observations. The median preoperative HDL-C level for all the subjects was 30 mg/dl (range, 24–53 mg/dl), and the median postcardiopulmonary bypass level was 21 mg/dl (range, 14–46 mg/dl) (p = 0.004). There was a tendency toward a moderate inverse correlation (–0.42) between the postcardiopulmonary bypass HDL-C level and the duration of chest tube drainage, but the result was not statistically significant (p = 0.07). In the chylous effusion group, the median postcardiopulmonary bypass HDL-C tended to be lower (16 vs. 23 mg/dl; p = 0.09). After the Fontan operation, the plasma HDL-C levels in children are significantly reduced. It is reasonable to conclude that the reduction in HDL-C reflects reduced plasma levels of HDL particles, which may have pertinent implications in postoperative pleural effusions given the antiinflammatory and endothelial barrier functions of HDL. PMID:22411716

  1. APOM and high-density lipoprotein cholesterol are associated with lung function and per cent emphysema.

    PubMed

    Burkart, Kristin M; Manichaikul, Ani; Wilk, Jemma B; Ahmed, Firas S; Burke, Gregory L; Enright, Paul; Hansel, Nadia N; Haynes, Demondes; Heckbert, Susan R; Hoffman, Eric A; Kaufman, Joel D; Kurai, Jun; Loehr, Laura; London, Stephanie J; Meng, Yang; O'Connor, George T; Oelsner, Elizabeth; Petrini, Marcy; Pottinger, Tess D; Powell, Charles A; Redline, Susan; Rotter, Jerome I; Smith, Lewis J; Soler Artigas, María; Tobin, Martin D; Tsai, Michael Y; Watson, Karol; White, Wendy; Young, Taylor R; Rich, Stephen S; Barr, R Graham

    2014-04-01

    Chronic obstructive pulmonary disease (COPD) is linked to cardiovascular disease; however, there are few studies on the associations of cardiovascular genes with COPD. We assessed the association of lung function with 2100 genes selected for cardiovascular diseases among 20 077 European-Americans and 6900 African-Americans. We performed replication of significant loci in the other racial group and an independent consortium of Europeans, tested the associations of significant loci with per cent emphysema and examined gene expression in an independent sample. We then tested the association of a related lipid biomarker with forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio and per cent emphysema. We identified one new polymorphism for FEV1/FVC (rs805301) in European-Americans (p=1.3×10(-6)) and a second (rs707974) in the combined European-American and African-American analysis (p=1.38×10(-7)). Both single-nucleotide polymorphisms (SNPs) flank the gene for apolipoprotein M (APOM), a component of high-density lipoprotein (HDL) cholesterol. Both were replicated in an independent cohort. SNPs in a second gene related to apolipoprotein M and HDL, PCSK9, were associated with FEV1/FVC ratio among African-Americans. rs707974 was associated with per cent emphysema among European-Americans and African-Americans and APOM expression was related to FEV1/FVC ratio and per cent emphysema. Higher HDL levels were associated with lower FEV1/FVC ratio and greater per cent emphysema. These findings suggest a novel role for the apolipoprotein M/HDL pathway in the pathogenesis of COPD and emphysema.

  2. Triglyceride-rich lipoproteins and high-density lipoprotein cholesterol in patients at high risk of cardiovascular disease: evidence and guidance for management.

    PubMed

    Chapman, M John; Ginsberg, Henry N; Amarenco, Pierre; Andreotti, Felicita; Borén, Jan; Catapano, Alberico L; Descamps, Olivier S; Fisher, Edward; Kovanen, Petri T; Kuivenhoven, Jan Albert; Lesnik, Philippe; Masana, Luis; Nordestgaard, Børge G; Ray, Kausik K; Reiner, Zeljko; Taskinen, Marja-Riitta; Tokgözoglu, Lale; Tybjærg-Hansen, Anne; Watts, Gerald F

    2011-06-01

    Even at low-density lipoprotein cholesterol (LDL-C) goal, patients with cardiometabolic abnormalities remain at high risk of cardiovascular events. This paper aims (i) to critically appraise evidence for elevated levels of triglyceride-rich lipoproteins (TRLs) and low levels of high-density lipoprotein cholesterol (HDL-C) as cardiovascular risk factors, and (ii) to advise on therapeutic strategies for management. Current evidence supports a causal association between elevated TRL and their remnants, low HDL-C, and cardiovascular risk. This interpretation is based on mechanistic and genetic studies for TRL and remnants, together with the epidemiological data suggestive of the association for circulating triglycerides and cardiovascular disease. For HDL, epidemiological, mechanistic, and clinical intervention data are consistent with the view that low HDL-C contributes to elevated cardiovascular risk; genetic evidence is unclear however, potentially reflecting the complexity of HDL metabolism. The Panel believes that therapeutic targeting of elevated triglycerides (≥ 1.7 mmol/L or 150 mg/dL), a marker of TRL and their remnants, and/or low HDL-C (<1.0 mmol/L or 40 mg/dL) may provide further benefit. The first step should be lifestyle interventions together with consideration of compliance with pharmacotherapy and secondary causes of dyslipidaemia. If inadequately corrected, adding niacin or a fibrate, or intensifying LDL-C lowering therapy may be considered. Treatment decisions regarding statin combination therapy should take into account relevant safety concerns, i.e. the risk of elevation of blood glucose, uric acid or liver enzymes with niacin, and myopathy, increased serum creatinine and cholelithiasis with fibrates. These recommendations will facilitate reduction in the substantial cardiovascular risk that persists in patients with cardiometabolic abnormalities at LDL-C goal. PMID:21531743

  3. Effect of nutritional counseling on low-density lipoprotein cholesterol among Thai HIV-infected adults receiving antiretroviral therapy.

    PubMed

    Chotivichien, Saipin; Arab, Lenore; Prasithsirikul, Wisit; Manosuthi, Weerawat; Sinawat, Sangsom; Detels, Roger

    2016-01-01

    HIV-infected patients receiving antiretroviral therapy have increased risk of metabolic syndrome, including dyslipidemia. In this study, we determined whether individual nutritional counseling reduced dyslipidemia, particularly low-density lipoprotein (LDL) cholesterol, among HIV-infected patients with dyslipidemia not currently taking lipid-lowering medication. We conducted a randomized 24-week trial among HIV-infected patients with dyslipidemia who were on antiretroviral therapy and were eligible to initiate therapeutic lifestyle changes according to the Thai National Cholesterol Education Program. Participants were randomly assigned to an intervention group that received individual counseling with a nutritionist for seven sessions (baseline, weeks 2, 4, 8, 12, 18, and 24) and a control group that received standard verbal diet information at baseline and nutritional counseling only at week 24. A 24-h recall technique was used to assess dietary intake for both groups at baseline and week 24. Lipid profile (total cholesterol, LDL, high-density lipoprotein (HDL), and triglyceride) was measured at baseline and after 12 and 24 weeks of therapy. An intention-to-treat and linear mixed model were used. Seventy-two patients were randomly assigned, and 62 (86%) participants completed their lipid profile test. After 12 weeks of follow-up, there were significant reductions in the intervention group for total cholesterol (-14.4 ± 4.6 mg/dL, P = .002), LDL cholesterol (-13.7 ± 4.1 mg/dL, P = .001), and triglyceride (-30.4 ± 13.8 mg/dL, P = .03). A significant reduction in LDL cholesterol was also observed in the control group (-7.7 ± 3.8 mg/dL, P = .04), but there were no significant differences in change of mean lipid levels between the groups at 12 weeks of follow-up. After 24 weeks, participants assigned to the intervention group demonstrated significantly greater decreases in serum total cholesterol (-19.0 ± 4.6 vs. 0.2

  4. Increased Free Cholesterol in Plasma Low and Very Low Density Lipoproteins in Non-Insulin-Dependent Diabetes Mellitus: Its Role in the Inhibition of Cholesteryl Ester Transfer

    NASA Astrophysics Data System (ADS)

    Fielding, Christopher J.; Reaven, Gerald M.; Liu, George; Fielding, Phoebe E.

    1984-04-01

    Recombination of low and very low density lipoproteins (VLDL and LDL) from normal subjects with plasma from patients with non-insulin-dependent diabetes mellitus significantly increased the reduced rate of transfer of cholesteryl ester to these lipoproteins, which is characteristic of diabetic plasma, whereas diabetic VLDL and LDL reduced cholesteryl ester transfer rates in normal plasma. VLDL and LDL from diabetic plasma had an increased ratio of free cholesterol to phospholipid compared to normal, and unlike normal VLDL and LDL spontaneously lost free cholesterol to high density lipoprotein. These data suggest that the block to cholesteryl ester transfer to these lipoproteins in non-insulin-dependent diabetes is mediated by their increased free cholesterol content and may be related to the increased risk of these patients for developing atherosclerosis.

  5. [Possibility of New Circulating Atherosclerosis-Related Lipid Markers Measurement in Medical and Complete Medical Checkups: Small Dense Low-Density Lipoprotein Cholesterol and Lipoprotein Lipase].

    PubMed

    Sumino, Hiroyuki; Nakajima, Katsuyuki; Murakami, Masami

    2016-03-01

    Small dense low-density lipoprotein cholesterol (sdLDL-C) concentrations correlate more strongly with cardiovascular disease (CVD) than other LDL-C and large LDL particle concentrations. Lipoprotein lipase (LPL) plays a central role in triglyceride-rich lipoprotein metabolism by catalyzing the hydrolysis of triglycerides in chylomicrons and very low-density lipoprotein particles and is a useful biomarker in diagnosing Type I, Type IV, and Type V hyperlipidemia. Therefore, the measurement of circulating sdLDL-C and LPL concentrations contributes to the assessment of circulating atherosclerosis-related lipid markers. However, the measurement of these lipids has not been fully adopted in medical and complete medical checkups. Recently, novel automated homogenous assay for measuring sdLDL-C and latex particle-enhanced turbidimetric immunoassay (LTIA) for measuring LPL have been developed, respectively. Using these new assays, sdLDL-C values showed excellent agreement with those obtained by isolation of the d = 1.044 - 1.063 g/mL plasma fraction by sequential ultracentrifugation, and LPL values measured with and without heparin injection were highly correlated with the values measured by the LPL-enzyme-linked immunosorbent assay (ELISA). These assays may be superior to the previous assays for the measurement of sdLDL-C and LPL concentrations due their simplicity and reproducibility. The measurements of sdLDL-C and LPL concentrations may be useful as lipid markers in the assessment of the development and progression of atherosclerosis and the detection of pathological conditions and diseases if these markers are measured in medical and complete medical checkups. We have introduced the possibility of the novel measurement of circulating atherosclerosis-related lipid markers such as sdLDL-C and LPL in medical and complete medical checkups. Further studies are needed to clarify whether sdLDL-C and LPL concentrations are related to the development and progression of

  6. Low density lipoprotein receptor-independent hepatic uptake of a synthetic, cholesterol-scavenging lipoprotein: implications for the treatment of receptor-deficient atherosclerosis

    SciTech Connect

    Williams, K.J.; Vallabhajosula, S.; Rahman, I.U.; Donnelly, T.M.; Parker, T.S.; Weinrauch, M.; Goldsmith, S.J.

    1988-01-01

    The metabolism of infused /sup 111/In-labeled phospholipid liposomes was examined in Watanabe heritable hyperlipidemic (WHHL) rabbits, which lack low density lipoprotein (LDL) receptors, and in normal control rabbits. The half-times (t/sub 1/2/) for clearance of /sup 111/In and excess phospholipid from plasma were 20.8 +/- 0.9 hr and 20.3 +/- 4.6 hr in WHHL and 20.0 +/- 0.8 hr and 19.6 +/- 2.2 hr in the normal rabbits. By 6 hr postinfusion, the plasma concentration of unesterified cholesterol increased by 2.2 +/- 0.23 mmol/liter in WHHL and 2.1 +/- 0.04 mmol/liter in normal rabbits, presumably reflecting mobilization of tissue sores. Disappearance of excess plasma cholesterol was > 90% complete in both groups of rabbits by 70 hr postinfusion. By quantitative ..gamma.. camera imaging, hepatic trapping of /sup 111/In-labeled liposomes over time was indistinguishable between the two groups. At autopsy, the liver was the major organ of clearance. Aortic uptake of /sup 111/In was < 0.02%. Thus, mobilization of cholesterol and hepatic uptake of phospholipid liposomes do not require LDL receptors. Because phospholipid infusions produce rapid substantial regression of atherosclerosis in genetically normal animals, the results suggest that phospholipid liposomes or triglyceride phospholipid emulsions (e.g., Intralipid) might reduce atherosclerosis in WHHL rabbits and in humans with familial hypercholesterolemia.

  7. [A rapid method for continuous flow measurement of cholesterol contained in high density lipoproteins (HDL) (author's transl)].

    PubMed

    Ponsot, P; Yvert, J P; Chevrier, M; Bon, R

    1981-01-01

    The authors utilized a reagent containing concanavalin A, a vegetal lecithin, to selectively precipitate lipoproteins containing apoprotein B, a component of VLDL, LDL, and Lp (a) which are well known for their atherogenic risk. During this precipitation "true" high density lipoproteins remain in solution. HDL cholesterol determination which constitutes an indirect indication of HDL activity or concentrations is performed by an enzymatic method using an automated continuous flow technique carried out on an Auto Analyzer II (Technicon Corp.). This rapid, easy determination obtains results comparable to other methods, particularly those chosen by the Société Française de Biologie Clinique (French Society of Clinical Biology). This technique should permit all laboratories to confirm an atherogenic index.

  8. Low HDL cholesterol is associated with increased atherogenic lipoproteins and insulin resistance in women classified with metabolic syndrome

    PubMed Central

    Jones, Jennifer J; Ackerman, Daniela; Barona, Jacqueline; Calle, Mariana; Comperatore, Michael V; Kim, Jung-Eun; Andersen, Catherine; Leite, Jose O; Volek, Jeff S; McIntosh, Mark; Kalynych, Colleen; Najm, Wadie; Lerman, Robert H

    2010-01-01

    Both metabolic syndrome (MetS) and elevated LDL cholesterol (LDL-C) increase the risk for cardiovascular disease (CVD). We hypothesized that low HDL cholesterol (HDL-C) would further increase CVD risk in women having both conditions. To assess this, we recruited 89 women with MetS (25-72 y) and LDL-C ≥ 2.6 mmol/L. To determine whether plasma HDL-C concentrations were associated with dietary components, circulating atherogenic particles, and other risk factors for CVD, we divided the subjects into two groups: high HDL-C (H-HDL) (≥ 1.3 mmol/L, n = 32) and low HDL-C (L-HDL) (< 1.3 mmol/L, n = 57). Plasma lipids, insulin, adiponectin, apolipoproteins, oxidized LDL, Lipoprotein(a), and lipoprotein size and subfractions were measured, and 3-d dietary records were used to assess macronutrient intake. Women with L-HDL had higher sugar intake and glycemic load (P < 0.05), higher plasma insulin (P < 0.01), lower adiponectin (P < 0.05), and higher numbers of atherogenic lipoproteins such as large VLDL (P < 0.01) and small LDL (P < 0.001) than the H-HDL group. Women with L-HDL also had larger VLDL and both smaller LDL and HDL particle diameters (P < 0.001). HDL-C was positively correlated with LDL size (r = 0.691, P < 0.0001) and HDL size (r = 0.606, P < 0.001), and inversely correlated with VLDL size (r = -0.327, P < 0.01). We concluded that L-HDL could be used as a marker for increased numbers of circulating atherogenic lipoproteins as well as increased insulin resistance in women who are already at risk for CVD. PMID:21286407

  9. Low HDL cholesterol is associated with increased atherogenic lipoproteins and insulin resistance in women classified with metabolic syndrome.

    PubMed

    Fernandez, Maria Luz; Jones, Jennifer J; Ackerman, Daniela; Barona, Jacqueline; Calle, Mariana; Comperatore, Michael V; Kim, Jung-Eun; Andersen, Catherine; Leite, Jose O; Volek, Jeff S; McIntosh, Mark; Kalynych, Colleen; Najm, Wadie; Lerman, Robert H

    2010-12-01

    Both metabolic syndrome (MetS) and elevated LDL cholesterol (LDL-C) increase the risk for cardiovascular disease (CVD). We hypothesized that low HDL cholesterol (HDL-C) would further increase CVD risk in women having both conditions. To assess this, we recruited 89 women with MetS (25-72 y) and LDL-C ≥ 2.6 mmol/L. To determine whether plasma HDL-C concentrations were associated with dietary components, circulating atherogenic particles, and other risk factors for CVD, we divided the subjects into two groups: high HDL-C (H-HDL) (≥ 1.3 mmol/L, n = 32) and low HDL-C (L-HDL) (< 1.3 mmol/L, n = 57). Plasma lipids, insulin, adiponectin, apolipoproteins, oxidized LDL, Lipoprotein(a), and lipoprotein size and subfractions were measured, and 3-d dietary records were used to assess macronutrient intake. Women with L-HDL had higher sugar intake and glycemic load (P < 0.05), higher plasma insulin (P < 0.01), lower adiponectin (P < 0.05), and higher numbers of atherogenic lipoproteins such as large VLDL (P < 0.01) and small LDL (P < 0.001) than the H-HDL group. Women with L-HDL also had larger VLDL and both smaller LDL and HDL particle diameters (P < 0.001). HDL-C was positively correlated with LDL size (r = 0.691, P < 0.0001) and HDL size (r = 0.606, P < 0.001), and inversely correlated with VLDL size (r = -0.327, P < 0.01). We concluded that L-HDL could be used as a marker for increased numbers of circulating atherogenic lipoproteins as well as increased insulin resistance in women who are already at risk for CVD.

  10. High-density lipoprotein-cholesterol levels and risk of cancer in HIV-infected subjects

    PubMed Central

    Squillace, Nicola; Galli, Laura; Bandera, Alessandra; Castagna, Antonella; Madeddu, Giordano; Caramello, Pietro; Antinori, Andrea; Cattelan, Annamaria; Maggiolo, Franco; Cingolani, Antonella; Gori, Andrea; Monforte, Antonella d’Arminio

    2016-01-01

    Abstract Investigation of the relationship between high-density lipoprotein-cholesterol (HDL-c) and the risk of developing cancer in a prospective cohort of human immunodeficiency virus (HIV)-infected patients. The Italian Cohort of Antiretroviral-naïve Patients Foundation Cohort is an Italian multicenter observational study recruiting HIV-positive patients while still antiretroviral treatment-naïve, regardless of the reason since 1997. Patients with at least 1 HDL-c value per year since enrollment and one such value before antiretroviral treatment initiation were included. HDL-c values were categorized as either low (<39 mg/dL in males or <49 mg/dL in females) or normal. Cancer diagnoses were classified as AIDS-defining malignancies (ADMs) or non-AIDS-defining malignancies (NADMs). Kaplan–Meier curves and Cox proportional-hazards regression models were used. Among 4897 patients (13,440 person-years of follow-up [PYFU]), 104 diagnoses of cancer were observed (56 ADMs, 48 NADMs) for an overall incidence rate of 7.7 (95% confidence interval [CI] 6.3–9.2) per 1000 PYFU. Low HDL-c values at enrollment were associated with higher risk both of cancer (crude hazard ratio [HR] 1.72, 95% CI 1.16–2.56, P = 0.007) and of NADM (crude HR 2.50, 95% CI 1.35–4.76, P = 0.003). Multivariate analysis showed that the risk of cancer diagnosis was higher in patients with low HDL-c values (adjusted HR [AHR] 1.87, 95% CI 1.18–2.95, P = 0.007) in older patients, those patients more recently enrolled, and in those with low current cluster of differentiation 4+ levels, and/or high current HIV-ribonucleic acid. The multivariate model confirmed an association between HDL-c (AHR 2.61, 95% CI 1.40–4.89, P = 0.003) and risk of NADM. Low HDL-c is an independent predictor of cancer in HIV-1-infected subjects. PMID:27603338

  11. Genetic analysis of long-lived families reveals novel variants influencing high density-lipoprotein cholesterol

    PubMed Central

    Feitosa, Mary F.; Wojczynski, Mary K.; Straka, Robert; Kammerer, Candace M.; Lee, Joseph H.; Kraja, Aldi T.; Christensen, Kaare; Newman, Anne B.; Province, Michael A.; Borecki, Ingrid B.

    2014-01-01

    The plasma levels of high-density lipoprotein cholesterol (HDL) have an inverse relationship to the risks of atherosclerosis and cardiovascular disease (CVD), and have also been associated with longevity. We sought to identify novel loci for HDL that could potentially provide new insights into biological regulation of HDL metabolism in healthy-longevous subjects. We performed a genome-wide association (GWA) scan on HDL using a mixed model approach to account for family structure using kinship coefficients. A total of 4114 subjects of European descent (480 families) were genotyped at ~2.3 million SNPs and ~38 million SNPs were imputed using the 1000 Genome Cosmopolitan reference panel in MACH. We identified novel variants near-NLRP1 (17p13) associated with an increase of HDL levels at genome-wide significant level (p < 5.0E-08). Additionally, several CETP (16q21) and ZNF259-APOA5-A4-C3-A1 (11q23.3) variants associated with HDL were found, replicating those previously reported in the literature. A possible regulatory variant upstream of NLRP1 that is associated with HDL in these elderly Long Life Family Study (LLFS) subjects may also contribute to their longevity and health. Our NLRP1 intergenic SNPs show a potential regulatory function in Encyclopedia of DNA Elements (ENCODE); however, it is not clear whether they regulate NLRP1 or other more remote gene. NLRP1 plays an important role in the induction of apoptosis, and its inflammasome is critical for mediating innate immune responses. Nlrp1a (a mouse ortholog of human NLRP1) interacts with SREBP-1a (17p11) which has a fundamental role in lipid concentration and composition, and is involved in innate immune response in macrophages. The NLRP1 region is conserved in mammals, but also has evolved adaptively showing signals of positive selection in European populations that might confer an advantage. NLRP1 intergenic SNPs have also been associated with immunity/inflammasome disorders which highlights the biological

  12. Forty-three loci associated with plasma lipoprotein size, concentration, and cholesterol content in genome-wide analysis.

    PubMed

    Chasman, Daniel I; Paré, Guillaume; Mora, Samia; Hopewell, Jemma C; Peloso, Gina; Clarke, Robert; Cupples, L Adrienne; Hamsten, Anders; Kathiresan, Sekar; Mälarstig, Anders; Ordovas, José M; Ripatti, Samuli; Parker, Alex N; Miletich, Joseph P; Ridker, Paul M

    2009-11-01

    While conventional LDL-C, HDL-C, and triglyceride measurements reflect aggregate properties of plasma lipoprotein fractions, NMR-based measurements more accurately reflect lipoprotein particle concentrations according to class (LDL, HDL, and VLDL) and particle size (small, medium, and large). The concentrations of these lipoprotein sub-fractions may be related to risk of cardiovascular disease and related metabolic disorders. We performed a genome-wide association study of 17 lipoprotein measures determined by NMR together with LDL-C, HDL-C, triglycerides, ApoA1, and ApoB in 17,296 women from the Women's Genome Health Study (WGHS). Among 36 loci with genome-wide significance (P<5x10(-8)) in primary and secondary analysis, ten (PCCB/STAG1 (3q22.3), GMPR/MYLIP (6p22.3), BTNL2 (6p21.32), KLF14 (7q32.2), 8p23.1, JMJD1C (10q21.3), SBF2 (11p15.4), 12q23.2, CCDC92/DNAH10/ZNF664 (12q24.31.B), and WIPI1 (17q24.2)) have not been reported in prior genome-wide association studies for plasma lipid concentration. Associations with mean lipoprotein particle size but not cholesterol content were found for LDL at four loci (7q11.23, LPL (8p21.3), 12q24.31.B, and LIPG (18q21.1)) and for HDL at one locus (GCKR (2p23.3)). In addition, genetic determinants of total IDL and total VLDL concentration were found at many loci, most strongly at LIPC (15q22.1) and APOC-APOE complex (19q13.32), respectively. Associations at seven more loci previously known for effects on conventional plasma lipid measures reveal additional genetic influences on lipoprotein profiles and bring the total number of loci to 43. Thus, genome-wide associations identified novel loci involved with lipoprotein metabolism-including loci that affect the NMR-based measures of concentration or size of LDL, HDL, and VLDL particles-all characteristics of lipoprotein profiles that may impact disease risk but are not available by conventional assay. PMID:19936222

  13. LRP5 and plasma cholesterol levels modulate the canonical Wnt pathway in peripheral blood leukocytes.

    PubMed

    Borrell-Pages, Maria; Carolina Romero, July; Badimon, Lina

    2015-08-01

    Inflammation is triggered after invasion or injury to restore homeostasis. Although the activation of Wnt/β-catenin signaling is one of the first molecular responses to cellular damage, its role in inflammation is still unclear. It was our hypothesis that the low-density lipoprotein (LDL) receptor-related protein 5 (LRP5) and the canonical Wnt signaling pathway are modulators of inflammatory mechanisms. Wild-type (WT) and LRP5(-/-) mice were fed a hypercholesterolemic (HC) diet to trigger dislipidemia and chronic inflammation. Diets were supplemented with plant sterol esters (PSEs) to induce LDL cholesterol lowering and the reduction of inflammation. HC WT mice showed increased serum cholesterol levels that correlated with increased Lrp5 and Wnt/β-catenin gene expression while in the HC LRP5(-/-) mice Wnt/β-catenin pathway was shut down. Functionally, HC induced pro-inflammatory gene expression in LRP5(-/-) mice, suggesting an inhibitory role of the Wnt pathway in inflammation. Dietary PSE administration downregulated serum cholesterol levels in WT and LRP5(-/-) mice. Furthermore, in WT mice PSE increased anti-inflammatory genes expression and inhibited Wnt/β-catenin activation. Hepatic gene expression of Vldlr, Lrp2 and Lrp6 was increased after HC feeding in WT mice but not in LRP5(-/-) mice, suggesting a role for these receptors in the clearance of plasmatic lipoproteins. Finally, an antiatherogenic role for LRP5 was demonstrated as HC LRP5(-/-) mice developed larger aortic atherosclerotic lesions than WT mice. Our results show an anti-inflammatory, pro-survival role for LRP5 and the Wnt signaling pathway in peripheral blood leukocytes.

  14. More Than Cholesterol Transporters: Lipoprotein Receptors in CNS Function and Neurodegeneration

    PubMed Central

    Lane-Donovan, Courtney E.; Philips, Gary T.; Herz, Joachim

    2014-01-01

    Members of the low-density lipoprotein (LDL) receptor gene family have a diverse set of biological functions that transcend lipid metabolism. Lipoprotein receptors have broad effects in both the developing and adult brain and participate in synapse development, cargo trafficking, and signal transduction. In addition, several family members play key roles in Alzheimer's disease pathogenesis and neurodegeneration. This review summarizes our current understanding of the role lipoprotein receptors play in CNS function and AD pathology, with a special emphasis on amyloid-independent roles in endocytosis and synaptic dysfunction. PMID:25144875

  15. Rice bran oil and oryzanol reduce plasma lipid and lipoprotein cholesterol concentrations and aortic cholesterol ester accumulation to a greater extent than ferulic acid in hypercholesterolemic hamsters.

    PubMed

    Wilson, Thomas A; Nicolosi, Robert J; Woolfrey, Benjamin; Kritchevsky, David

    2007-02-01

    Our laboratory has reported that the hypolipidemic effect of rice bran oil (RBO) is not entirely explained by its fatty acid composition. Because RBO has a greater content of the unsaponifiables, which also lower cholesterol compared to most vegetable oils, we wanted to know whether oryzanol or ferulic acid, two major unsaponifiables in RBO, has a greater cholesterol-lowering activity. Forty-eight F(1)B Golden Syrian hamsters (Mesocricetus auratus) (BioBreeders, Watertown, MA) were group housed (three per cage) in cages with bedding in an air-conditioned facility maintained on a 12-h light/dark cycle. The hamsters were fed a chow-based hypercholesterolemic diet (HCD) containing 10% coconut oil and 0.1% cholesterol for 2 weeks, at which time they were bled after an overnight fast (16 h) and segregated into 4 groups of 12 with similar plasma cholesterol concentrations. Group 1 (control) continued on the HCD, group 2 was fed the HCD containing 10% RBO in place of coconut oil, group 3 was fed the HCD plus 0.5% ferulic acid and group 4 was fed the HCD plus 0.5% oryzanol for an additional 10 weeks. After 10 weeks on the diets, plasma total cholesterol (TC) and non-high-density lipoprotein cholesterol (HDL-C) (very low- and low-density lipoprotein) concentrations were significantly lower in the RBO (-64% and -70%, respectively), the ferulic acid (-22% and -24%, respectively) and the oryzanol (-70% and -77%, respectively) diets compared to control. Plasma TC and non-HDL-C concentrations were also significantly lower in the RBO (-53% and -61%, respectively) and oryzanol (-61% and -70%, respectively) diets compared to the ferulic acid. Compared to control and ferulic acid, plasma HDL-C concentrations were significantly higher in the RBO (10% and 20%, respectively) and oryzanol (13% and 24%, respectively) diets. The ferulic acid diet had significantly lower plasma HDL-C concentrations compared to the control (-9%). The RBO and oryzanol diets were significantly lower for

  16. Effect of ETC-1002 on Serum Low-Density Lipoprotein Cholesterol in Hypercholesterolemic Patients Receiving Statin Therapy.

    PubMed

    Ballantyne, Christie M; McKenney, James M; MacDougall, Diane E; Margulies, Janice R; Robinson, Paula L; Hanselman, Jeffrey C; Lalwani, Narendra D

    2016-06-15

    ETC-1002 is an oral, once-daily medication that inhibits adenosine triphosphate citrate lyase, an enzyme upstream of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, to reduce cholesterol biosynthesis. ETC-1002 monotherapy has demonstrated significant reduction in low-density lipoprotein cholesterol (LDL-C) compared with placebo in phase 2 studies. The objective of this study was to compare the lipid-lowering efficacy of ETC-1002 versus placebo when added to ongoing statin therapy in patients with hypercholesterolemia. This phase 2b, multicenter, double-blind trial (NCT02072161) randomized 134 hypercholesterolemic patients (LDL-C, 115 to 220 mg/dl) on stable background statin therapy to 12 weeks of add-on treatment with ETC-1002 120 mg, ETC-1002 180 mg, or placebo. The primary efficacy end point was the percent change in calculated LDL-C from baseline to week 12. For LDL-C, the least-squares mean percent change ± standard error from baseline to week 12 was significantly greater with ETC-1002 120 mg (-17 ± 4%, p = 0.0055) and ETC-1002 180 mg (-24 ± 4%, p <0.0001) than placebo (-4 ± 4%). ETC-1002 also dose dependently reduced apolipoprotein B by 15% to 17%, non-high-density lipoprotein cholesterol by 14% to 17%, total cholesterol by 13% to 15%, and LDL particle number by 17% to 21%. All these reductions in ETC-1002-treated cohorts were significantly greater than those with placebo. Rates of adverse events (AEs), muscle-related AEs, and discontinuations for AEs with ETC-1002 were similar to placebo. In conclusion, ETC-1002 120 mg or 180 mg added to stable statin therapy significantly reduced LDL-C compared to placebo and has a similar tolerability profile. PMID:27138185

  17. High-density lipoprotein cholesterol strongly discriminates between healthy free-living and disabled octo-nonagenarians: a cross sectional study. Associazione Medica Sabin.

    PubMed

    Zuliani, G; Palmieri, E; Volpato, S; Bader, G; Mezzetti, A; Costantini, F; Sforza, G R; Imbastaro, T; Romagnoni, F; Fellin, R

    1997-10-01

    Aging is frequently associated with a deterioration in health and functional status, which often induces important modifications in several biological parameters, including plasma lipids; as a consequence, the real "meaning" of lipoprotein parameters in old individuals is complex. A cross sectional study was carried out in order to investigate the lipoprotein profile in very old individuals with or without disability, and evaluate the possible influence of other biological variables on plasma lipids. One hundred selected healthy free-living (FL) and 62 disabled (DIS) subjects aged over 80 were enrolled; 91 healthy adults matched for origin were included as controls. Lipoprotein profile [total cholesterol, triglycerides, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, apoprotein A-I and B], anthropometric parameters, and ADL were measured. The FL octo-nonagenarians featured higher HDL-cholesterol levels than adult controls. DIS octo-nonagenarians showed lower total and HDL-C levels than FL. Discriminant analysis indicated that HDL-cholesterol and apoprotein A-I, but not total cholesterol, strongly discriminated between FL and DIS octo-nonagenarians. Multivariate analysis demonstrated that the waist/hip ratio, an index of visceral adiposity, was negatively associated with HDL-C levels in FL, but not in DIS elderly. We conclude that: 1) in very old individuals, the absence or presence of disability is strongly associated with high or low HDL-cholesterol values, respectively; 2) HDL-C and apo A-I are the parameters which better discriminate between FL and DIS octo-nonagenarians; and 3) the differences in HDL-C levels between FL and DIS are not due to modifications in anthropometric parameters. Prospective studies are needed to better understand the relationship between high-density lipoprotein levels, disability and aging. PMID:9458994

  18. A review of low-density lipoprotein cholesterol, treatment strategies, and its impact on cardiovascular disease morbidity and mortality.

    PubMed

    Wadhera, Rishi K; Steen, Dylan L; Khan, Irfan; Giugliano, Robert P; Foody, JoAnne M

    2016-01-01

    Cardiovascular (CV) disease is a leading cause of death worldwide, accounting for approximately 31.4% of deaths globally in 2012. It is estimated that, from 1980 to 2000, reduction in total cholesterol accounted for a 33% decrease in coronary heart disease (CHD) deaths in the United States. In other developed countries, similar decreases in CHD deaths (ranging from 19%-46%) have been attributed to reduction in total cholesterol. Low-density lipoprotein cholesterol (LDL-C) has now largely replaced total cholesterol as a risk marker and the primary treatment target for hyperlipidemia. Reduction in LDL-C levels by statin-based therapies has been demonstrated to result in a reduction in the risk of nonfatal CV events and mortality in a continuous and graded manner over a wide range of baseline risk and LDL-C levels. This article provides a review of (1) the relationship between LDL-C and CV risk from a biologic, epidemiologic, and genetic standpoint; (2) evidence-based strategies for LDL-C lowering; (3) lipid-management guidelines; (4) new strategies to further reduce CV risk through LDL-C lowering; and (5) population-level and health-system initiatives aimed at identifying, treating, and lowering lifetime LDL-C exposure. PMID:27206934

  19. Discordance of Low-Density Lipoprotein and High-Density Lipoprotein Cholesterol Particle Versus Cholesterol Concentration for the Prediction of Cardiovascular Disease in Patients With Metabolic Syndrome and Diabetes Mellitus (from the Multi-Ethnic Study of Atherosclerosis [MESA]).

    PubMed

    Tehrani, David M; Zhao, Yanglu; Blaha, Michael J; Mora, Samia; Mackey, Rachel H; Michos, Erin D; Budoff, Matthew J; Cromwell, William; Otvos, James D; Rosenblit, Paul D; Wong, Nathan D

    2016-06-15

    A stronger association for low-density lipoprotein particle (LDL-P) and high-density lipoprotein particle (HDL-P) versus cholesterol concentrations (LDL-C and HDL-C) in predicting coronary heart disease (CHD) has been noted. We evaluate the role of these factors and extent of particle-cholesterol discordance in those with diabetes mellitus (DM) and metabolic syndrome (MetS) for event prediction. In the Multi-Ethnic Study of Atherosclerosis, we examined discordance of LDL and HDL (defined as a subject's difference between baseline particle and cholesterol percentiles), LDL-C, LDL-P, HDL-C, and HDL-P in relation to incident CHD and cardiovascular disease (CVD) events in subjects with DM, MetS (without DM), or neither condition using Cox regression. Of the 6,417 subjects with 10-year follow-up, those with MetS (n = 1,596) and DM (n = 838) had significantly greater LDL and HDL discordance compared with those without these conditions. In discordance models, only LDL discordance (per SD) within the MetS group was positively associated with CHD events (adjusted hazard ratio [HR] = 1.22, 95% confidence interval [CI] 1.01 to 1.48, p <0.05). In models with individual particle/cholesterol variables (per SD), within the DM group, HDL-P was inversely (HR 0.71, 95% CI 0.52 to 0.96, p <0.05) and LDL-C positively (HR 1.47, 95% CI 1.07 to 2.03, p <0.05) associated with CHD. In those with MetS, only LDL-P was positively associated with CHD (HR 1.34, 95% CI 1.00 to 1.78, p <0.05). Similar findings were also seen for CVD. LDL discordance and higher LDL-P in MetS, and higher LDL-C and lower HDL-P in DM, predict CHD and CVD, supporting a potential role for examining lipoprotein particles and discordances in those with MetS and DM.

  20. [THE SPIRIT CHOLESTEROL, BIOLOGICA L ROLE AT STAGES OF PHYLOGENESIS, MECHANISMS OF INHIBITION OF SYNTHESIS OF STEROL BY STATINS, FACTORS OF PHARMACOGENOMICS AND DIAGNOSTIC SIGNIFICANCE OF CHOLESTEROL OF LIPOPROTEINS OF LOW DENSITY].

    PubMed

    Titov, V N; Kotlovskii, M Yu; Pokrovskii, A A; Kotlovskaia, O S; Osedko, A V; Titova, N M; Kotlovskii, Yu V; Digaii, A M

    2015-04-01

    The hypolipidemic effect of statins is realized by inhibition of synthesis of local pool of cholesterol spirit in endoplasmic net of hepatocytes. The cholesterol spirit covers all hydrophobic medium of triglycerides with polar mono layer of phosphatidylcholines and cholesterol spirit prior to secretion of lipoproteins of very low density into hydrophilic medium. The lesser mono layer between lipase enzyme and triglycerides substrate contains of cholesterol spirit the higher are the parameters of hydrolysis of palmitic and oleic lipoproteins of very low density. The sequence of effect of statins is as follows: blocking of synthesis in hepatocytes and decreasing of content of unesterified cholesterol spirit in blood plasma; activation of hydrolysis of triglycerides in palmitic and oleic lipoproteins of very low density; formation of ligand lipoproteins of very low density and their absorption by cells by force of apoB-100 endocytosis; decreasing in blood of content of polyenoic fatty acids, equimolar esterified by cholesterol spirit, polyethers of cholesterol spirit and decreasing of level of cholesterol spirit-lipoproteins of very low density. There is no way to eliminate aphysiological effect of disordered biological function of trophology (nutrition) on metabolism of fatty acids in population by means of pharmaceuticals intake. It is necessary to eliminate aphysiological effect of environment. To decrease rate of diseases of cardiovascular system one has to decrease in food content of saturated fatty acids and in the first instance palmitic saturated fatty acid, trans-form fatty acid, palmitoleic fatty acids up to physiological values and increase to the same degree the content of polyenoic fatty acids. The saturated fatty acids block absorption of polyenoic fatty acids by cells. The atherosclerosis is a deficiency of polyenoic fatty acids under surplus of palmitic saturated fatty acid. PMID:26189285

  1. Apolipoprotein A-I configuration and cell cholesterol efflux activity of discoidal lipoproteins depend on the reconstitution process.

    PubMed

    Cuellar, Luz Ángela; Prieto, Eduardo Daniel; Cabaleiro, Laura Virginia; Garda, Horacio Alberto

    2014-01-01

    Discoidal high-density lipoproteins (D-HDL) are critical intermediates in reverse cholesterol transport. Most of the present knowledge of D-HDL is based on studies with reconstituted lipoprotein complexes of apolipoprotein A-I (apoA-I) obtained by cholate dialysis (CD). D-HDL can also be generated by the direct microsolubilization (DM) of phospholipid vesicles at the gel/fluid phase transition temperature, a process mechanistically similar to the "in vivo" apoAI lipidation via ABCA1. We compared the apoA-I configuration in D-HDL reconstituted with dimyristoylphosphatidylcholine by both procedures using fluorescence resonance energy transfer measurements with apoA-I tryptophan mutants and fluorescently labeled cysteine mutants. Results indicate that apoA-I configuration in D-HDL depends on the reconstitution process and are consistent with a "double belt" molecular arrangement with different helix registry. As reported by others, a configuration with juxtaposition of helices 5 of each apoAI monomer (5/5 registry) predominates in D-HDL obtained by CD. However, a configuration with helix 5 of one monomer juxtaposed with helix 2 of the other (5/2 registry) would predominate in D-HDL generated by DM. Moreover, we also show that the kinetics of cholesterol efflux from macrophage cultures depends on the reconstitution process, suggesting that apoAI configuration is important for this HDL function. PMID:24201377

  2. Low density lipoprotein receptor-independent hepatic uptake of a synthetic, cholesterol-scavenging lipoprotein: implications for the treatment of receptor-deficient atherosclerosis.

    PubMed Central

    Williams, K J; Vallabhajosula, S; Rahman, I U; Donnelly, T M; Parker, T S; Weinrauch, M; Goldsmith, S J

    1988-01-01

    The metabolism of infused 111In-labeled phospholipid liposomes was examined in Watanabe heritable hyperlipidemic (WHHL) rabbits, which lack low density lipoprotein (LDL) receptors, and in normal control rabbits. The half-times (t1/2) for clearance of 111In and excess phospholipid from plasma were 20.8 +/- 0.9 hr and 20.3 +/- 4.6 hr in WHHL and 20.0 +/- 0.8 hr and 19.6 +/- 2.2 hr in the normal rabbits (means +/- SEM; n = 4). By 6 hr postinfusion, the plasma concentration of unesterified cholesterol increased by 2.2 +/- 0.23 mmol/liter in WHHL and 2.1 +/- 0.04 mmol/liter in normal rabbits, presumably reflecting mobilization of tissue stores. Disappearance of excess plasma cholesterol was greater than 90% complete in both groups of rabbits by 70 hr postinfusion. By quantitative gamma camera imaging, hepatic trapping of 111In-labeled liposomes over time was indistinguishable between the two groups. At autopsy, the liver was the major organ of clearance, acquiring 22.0% +/- 1.7% (WHHL) and 16.8% +/- 1.0% (normal of total 111In. Aortic uptake of 111In was less than 0.02%. Thus, mobilization of cholesterol and hepatic uptake of phospholipid liposomes do not require LDL receptors. Because phospholipid infusions produce rapid substantial regression of atherosclerosis in genetically normal animals, our results suggest that phospholipid liposomes or triglyceride phospholipid emulsions (e.g., Intralipid) might reduce atherosclerosis in WHHL rabbits and in humans with familial hypercholesterolemia. PMID:3422421

  3. Lipoprotein cholesterol and triglyceride concentrations associated with dog body condition score; effect of recommended fasting duration on sample concentrations in Japanese private clinics

    PubMed Central

    USUI, Shiho; YASUDA, Hidemi; KOKETSU, Yuzo

    2015-01-01

    The objectives of this study were to survey clinics’ guidance about recommended fasting duration (FD) prior to lipoprotein analysis, and to characterize lipoprotein cholesterol and triglyceride concentrations in obese and overweight dogs categorized on the basis of the 5-point body condition score (BCS) scale. A dataset was created from lipoprotein analysis medical records of 1,538 dogs from 75 breeds in 354 clinics from 2012 to 2013. A phone survey was conducted to obtain the clinics’ FD. Two-level linear mixed-effects models were applied to the data. Over 50% of the clinics said they recommended fasting for 12 hr or more. Dogs in clinics with FD 12 hr or more had lower chylomicron triglyceride concentrations than those in clinics with FD less than 8 hr (P=0.05). Mean (± SEM) BCS at sampling was 3.7 ± 0.02. Obese and overweight dogs had higher very low density lipoprotein (VLDL) and high density lipoprotein (HDL) cholesterol and triglyceride concentrations than ideal dogs (P<0.05), but no such difference was found for low density lipoprotein cholesterol and triglyceride concentrations (P≥0.07). Across all BCS, as dog age rose from 0 to 8 years old, HDL cholesterol concentrations decreased by 13.5 mg/dl, whereas VLDL triglyceride concentrations increased by 81.7 mg/dl (P<0.05). In conclusion, FD of 8 hr or less may affect lipoprotein lipid concentrations. Obese and overweight dogs were characterized as having high VLDL and HDL cholesterol and triglyceride concentrations. PMID:25866404

  4. At what levels of total low- or high-density lipoprotein cholesterol should diet/drug therapy be initiated? United States guidelines.

    PubMed

    LaRosa, J C

    1990-03-20

    Guidelines for the detection, evaluation and treatment of hypercholesterolemia in adults have been established in the United States. These guidelines recommend that total cholesterol levels be used for screening purposes. Total cholesterol levels greater than 240 mg/dl are considered "high," those from 200 to 239 mg/dl "borderline," and those less than 200 mg/dl "normal," regardless of the person's age or gender. All persons in the high category, as well as those in the borderline category who have other risk factors or established vascular disease, require measurements of low-density lipoprotein (LDL) cholesterol levels. LDL cholesterol levels are used to guide the selection of treatment. Patients with LDL cholesterol levels greater than 130 mg/dl are candidates for active diet therapy. Those whose LDL cholesterol levels are 160 to 190 mg/dl after 3 to 6 months of diet therapy are candidates for drug therapy. A high-density lipoprotein (HDL) level less than 35 mg/dl is considered a risk factor and may influence the level of LDL at which drug therapy is initiated. Some observers have expressed concern that these guidelines overemphasize LDL cholesterol at the expense of total cholesterol, HDL cholesterol and triglyceride levels. Nevertheless, the guidelines have been broadly accepted and currently serve as the basis for a widespread public-health education program.

  5. Serum lipoprotein composition, lecithin cholesterol acyltransferase and tissue lipase activities in pregnant diabetic rats and their offspring receiving enriched n-3 PUFA diet.

    PubMed

    Soulimane-Mokhtari, N A; Guermouche, B; Saker, M; Merzouk, S; Merzouk, H; Hichami, A; Madani, S; Khan, N A; Prost, J

    2008-03-01

    The effects of dietary n-3 polyunsaturated fatty acids on lipoprotein concentrations and on lipoprotein lipase (LPL), hepatic triglyceride lipase (HTGL) and lecithin cholesterol acyltransferase (LCAT) activities were studied in streptozotocin-induced diabetic rats during pregnancy and in their macrosomic offspring from birth to adulthood. Pregnant diabetic and control rats were fed Isio-4 diet (vegetable oil) or EPAX diet (concentrated marine omega-3 EPA/DHA oil), the same diets were consumed by pups at weaning. Compared with control rats, diabetic rats showed, during pregnancy, a significant elevation in very low density lipoprotein (VLDL) and low and high density lipoprotein (LDL-HDL(1))-triglyceride, cholesterol and apoprotein B100 concentrations and a reduction in apoprotein A-I levels. HTGL activity was high while LPL and LCAT activities were low in these rats. The macrosomic pups of Isio-4-fed diabetic rats showed a significant enhancement in triglyceride and cholesterol levels at birth and during adulthood with a concomitant increase in lipase and LCAT activities. EPAX diet induces a significant diminution of VLDL and LDL-HDL(1) in mothers and in their macrosomic pups, accompanied by an increase in cholesterol and apoprotein A-I levels in HDL(2-3) fraction. It also restores LPL, HTGL and LCAT activities to normal range. EPAX diet ameliorates considerably lipoprotein disorders in diabetic mothers and in their macrosomic offspring. PMID:18436977

  6. The effect of 17 beta-estradiol on cholesterol in human macrophages is influenced by the lipoprotein milieu

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Estrogen and testosterone are thought to modulate coronary heart disease (CHD) risk. To examine how these hormones affect human macrophage cholesterol transport, a key factor in atherogenesis, we obtained monocytes from healthy male and postmenopausal female donors (age 50-70 y). Cells were allowe...

  7. Add-on rosiglitazone therapy improves plasminogen activity and high-density lipoprotein cholesterol in type 2 diabetes mellitus.

    PubMed

    Mustaffa, Nazri; Ibrahim, Suhairi; Abdullah, Wan Zaidah; Yusof, Zurkurnai

    2011-09-01

    Rosiglitazone is an oral hypoglycaemic agent of the thiazolidinedione group. This study aimed to assess changes in the diabetic prothrombotic state via plasminogen activity and changes in surrogate markers of atherosclerotic burden via ankle-brachial pressure index (ABPI) measurements after rosiglitazone was added to a pre-existing type 2 diabetes mellitus treatment regime. A nonblinded interventional study was designed. Fifty-nine patients were enrolled. Rosiglitazone-naïve patients were prescribed oral rosiglitazone 4 mg daily for 10 weeks. ABPI, plasminogen activity, glycosylated haemoglobin (HbA1c) and fasting lipid profile were measured pretreatment and post-treatment. Forty-eight patients completed the study. At the end of this study, mean plasminogen activity improvement was nearly 16% (P<0.05), mean ABPI improvement was 0.01 (P=0.439), mean HbA1c reduction was 0.51% (P<0.05), mean total cholesterol (TC) increase was 0.36 mmol/l (P<0.05), mean high-density lipoprotein cholesterol (HDL-C) increase was 0.15 mmol/l (P<0.05) and mean low-density lipoprotein cholesterol increased by 0.19 mmol/l (P=0.098). Rosiglitazone significantly improved plasminogen activity. There was also significant HbA1c reduction, and rise in both TC and HDL-C. Thus, rosiglitazone potentially improves the atherosclerotic burden and prothrombotic state. In future, more studies are needed to confirm the relationship between rosiglitazone, fibrinolytic system and atheromatous reduction in type 2 diabetes mellitus. PMID:21537159

  8. Inactive lipoprotein lipase (LPL) alone increases selective cholesterol ester uptake in vivo, whereas in the presence of active LPL it also increases triglyceride hydrolysis and whole particle lipoprotein uptake.

    PubMed

    Merkel, Martin; Heeren, Jörg; Dudeck, Wiebke; Rinninger, Franz; Radner, Herbert; Breslow, Jan L; Goldberg, Ira J; Zechner, Rudolf; Greten, Heiner

    2002-03-01

    We have previously shown that transgenic expression of catalytically inactive lipoprotein lipase (LPL) in muscle (Mck-N-LPL) enhances triglyceride hydrolysis as well as whole particle lipoprotein and selective cholesterol ester uptake. In the current study, we have examined whether these functions can be performed by inactive LPL alone or require the presence of active LPL expressed in the same tissue. To study inactive LPL in the presence of active LPL in the same tissue, the Mck-N-LPL transgene was bred onto the heterozygous LPL-deficient (LPL1) background. At 18 h of age, Mck-N-LPL reduced triglycerides by 35% and markedly increased muscle lipid droplets. In adult mice, it reduced triglycerides by 40% and increased lipoprotein particle uptake into muscle by 60% and cholesterol ester uptake by 110%. To study inactive LPL alone, the Mck-N-LPL transgene was bred onto the LPL-deficient (LPL0) background. These mice die at approximately 24 h of age. At 18 h of age, in the absence of active LPL, inactive LPL expression did not diminish triglycerides nor did it result in the accumulation of muscle lipid droplets. To study inactive LPL in the absence of active LPL in the same tissue in adult animals, the Mck-N-LPL transgene was bred onto mice that only expressed active LPL in the heart (LPL0/He-LPL). In this case, Mck-N-LPL did not reduce triglycerides or increase the uptake of lipoprotein particles but did increase muscle uptake of chylomicron and very low density lipoprotein cholesterol ester by 40%. Thus, in the presence of active LPL in the same tissue, inactive LPL augments triglyceride hydrolysis and increases whole particle triglyceride-rich lipoprotein and selective cholesterol ester uptake. In the absence of active LPL in the same tissue, inactive LPL only mediates selective cholesterol ester uptake.

  9. Rice bran proteins and their hydrolysates modulate cholesterol metabolism in mice on hypercholesterolemic diets.

    PubMed

    Zhang, Huijuan; Wang, Jing; Liu, Yingli; Gong, Lingxiao; Sun, Baoguo

    2016-06-15

    The hypolipidemic properties of defatted rice bran protein (DRBP), fresh rice bran protein (FRBP), DRBP hydrolysates (DRBPH), and FRBP hydrolysates (FRBPH) were determined in mice on high fat diets for four weeks. Very low-density lipoprotein cholesterol (VLDL-C), low-density lipoprotein cholesterol (LDL-C) contents, and the hepatic total cholesterol content were reduced while fecal total cholesterol and total bile acid (TBA) contents were increased in the FRBPH diet group. The expression levels of hepatic genes for cholesterol biosynthesis HMG-CoAR and SREBP-2 were lowest in the FRBPH diet group. The mRNA level of HMG-CoAR was significantly positively correlated with the hepatic TG content (r = 0.82, P < 0.05). The mRNA levels of genes related to bile acid biosynthesis and cholesterol efflux, CYP7A1, ABCA1, and PPARγ were up-regulated in all test groups. The results suggest that FRBPH regulates cholesterol metabolism in mice fed the high fat and cholesterol diet by increasing fecal steroid excretion and expression levels of genes related to bile acid synthesis and cholesterol efflux, and the down-regulation of the expression levels of genes related to cholesterol biosynthesis. PMID:27216972

  10. [The new atherogenic plasma index reflects the triglyceride and HDL-cholesterol ratio, the lipoprotein particle size and the cholesterol esterification rate: changes during lipanor therapy].

    PubMed

    Dobiásová, M; Frohlich, J

    2000-03-01

    The new atherogenic plasma index (AIP) is a logarithmic transformation of the ratio of the molar triglyceride (TG) concentration and high density lipoprotein cholesterol (HDL-C). AIP correlates closely with the size of LDL particles (r = 0.8) and esterification rate of plasma cholesterol devoid of apo B lipoproteins (FERHDL), r = 0.9 which are considered at present the most sensitive indicators of the atherogenic plasma profile. AIP was recommended by the authors, based on analysis of results of 11 previous studies (1156 subjects) where FERHDL and plasma lipid parameters were investigated in different groups of people who differed as to the atherogenic risk. The AIP index was moreover used for evaluation of a clinical study comprising 609 patients with hyperlipidaemia, who were treated for three months with ciprofibrate (Lipanor). The mean AIP values of non-risk groups (plasma from umbilical blood, children, healthy women etc.) equalled zero or were lower, while with an increasing atherogenic risk (men, women after the menopause) AIP reached positive values, incl. high positive values in risk groups (plasma of diabetic subjects, patients with HLP, patients with positive angiography, myocardial infarction etc.). In all groups women had lower AIP values as compared with males. In patients after Lipanor therapy the AIP declined (from 0.58 +/- 0.17 to 0.33_0.18 in men, from 0.50 +/- 0.18 to 0.21 +/- 0.19 in women). If we consider AIP values from negative ones to 0.15 as "safe" from the aspect of atherogenicity, before Lipanor treatment these "safe" levels were recorded in 1.5% men and in 5.2% women and after treatment in 32% men and 48% women. The results indicate, that AIP which reflects the plasma lipoprotein profile quantifies the relations between TG and HDL-C and thus can be an objective indicator of the atherogenic risk and effectiveness of treatment and it is useful because it can be assessed in any surgery. PMID:11048517

  11. Effect of 2 month controlled green tea intervention on lipoprotein cholesterol, glucose, and hormone levels in healthy postmenopausal women

    PubMed Central

    Wu, Anna H.; Spicer, Darcy; Stanczyk, Frank Z.; Tseng, Chiu-chen; Yang, Chung S.; Pike, Malcolm C.

    2013-01-01

    There have been no controlled intervention studies to investigate the effects of green tea on circulating hormone levels, an established breast cancer risk factor. We conducted a randomized, double-blind, placebo-controlled intervention study to investigate the effect of the main green tea catechin, epigallocatechin gallate (EGCG), taken in a green tea extract, Polyphenon E (PPE). Postmenopausal women (n=103) were randomized into three arms: placebo, 400 mg EGCG as PPE, or 800 mg EGCG as PPE as capsules per day for 2 months. Urinary tea catechin and serum estrogen, androgen, lipid, glucose-related markers, adiponectin, and growth factor levels were measured at baseline and at the end of months 1 and 2 of intervention. Based on urinary tea catechin concentrations, compliance was excellent. Supplementation with PPE did not produce consistent patterns of changes in estradiol (E2), estrone (E1), or testosterone (T) levels. Low density lipoprotein (LDL)-cholesterol decreased significantly in both PPE groups but was unchanged in the placebo group; the change in LDL-cholesterol differed between the placebo and PPE groups (P=0.02). Glucose and insulin levels decreased nonsignificantly in the PPE groups but increased in the placebo group; statistically significant differences in changes in glucose (P=0.008) and insulin (P=0.01) were found. In summary, green tea (400 and 800 mg EGCG as PPE; ~5–10 cups) supplementation for 2 months had suggestive beneficial effects on LDL cholesterol concentrations and glucose-related markers. PMID:22246619

  12. Effect of 2-month controlled green tea intervention on lipoprotein cholesterol, glucose, and hormone levels in healthy postmenopausal women.

    PubMed

    Wu, Anna H; Spicer, Darcy; Stanczyk, Frank Z; Tseng, Chiu-Chen; Yang, Chung S; Pike, Malcolm C

    2012-03-01

    There have been no controlled intervention studies to investigate the effects of green tea on circulating hormone levels, an established breast cancer risk factor. We conducted a double-blind, randomized, placebo-controlled intervention study to investigate the effect of the main green tea catechin, epigallocatechin gallate (EGCG), taken in a green tea extract, polyphenon E (PPE). Postmenopausal women (n = 103) were randomized into three arms: placebo, 400-mg EGCG as PPE, or 800-mg EGCG as PPE as capsules per day for 2 months. Urinary tea catechin and serum estrogen, androgen, lipid, glucose-related markers, adiponectin, and growth factor levels were measured at baseline and at the end of months 1 and 2 of intervention. On the basis of urinary tea catechin concentrations, compliance was excellent. Supplementation with PPE did not produce consistent patterns of changes in estradiol (E2), estrone (E1), or testosterone (T) levels. Low-density lipoprotein (LDL)-cholesterol decreased significantly in both PPE groups but was unchanged in the placebo group; the change in LDL-cholesterol differed between the placebo and PPE groups (P = 0.02). Glucose and insulin levels decreased nonsignificantly in the PPE groups but increased in the placebo group; statistically significant differences in changes in glucose (P = 0.008) and insulin (P = 0.01) were found. In summary, green tea (400- and 800-mg EGCG as PPE; ∼5-10 cups) supplementation for 2 months had suggestive beneficial effects on LDL-cholesterol concentrations and glucose-related markers.

  13. Soy milk powder supplemented with phytosterol esters reduced serum cholesterol level in hypercholesterolemia independently of lipoprotein E genotype: a random clinical placebo-controlled trial.

    PubMed

    Dong, Shan; Zhang, Ran; Ji, Ya-Cheng; Hao, Jia-Yin; Ma, Wei-Wei; Chen, Xu-Dong; Xiao, Rong; Yu, Huan-Ling

    2016-08-01

    Phytosterols (PSs) are reported to lower the serum total cholesterol and low-density lipoprotein cholesterol concentrations enriched in some fatty foods, such as margarine. However, these high-fat foods are not very suitable for older people. Soy milk is the favorite food for elderly people in China; therefore, we hypothesized that the consumption of soy milk powder supplemented with PSs would decrease the serum cholesterol levels in older Chinese people independent of the genotypes of apolipoprotein E (ApoE). Mild to moderate hyperlipidemic patients (n = 170) were recruited from different communities and treated with placebo soy milk powder or 3.4 g PS esters-enriched soy milk powder (2.0 g/d free PS in 30 g soy milk powder). The fasting serum lipid profiles at the baseline and after 3 and 6 months of intervention were measured. The ApoE genotype was also determined. After 3 months of PS intervention, the serum lipid profile was not changed significantly in either group. The serum total cholesterol, low-density lipoprotein cholesterol, and non- high-density lipoprotein cholesterol levels decreased by 9.3%, 11.4%, and 12.6%, respectively, in the PS group at the end of the intervention (6 months) compared with the control group, whereas the serum high-density lipoprotein cholesterol and triglyceride levels were not affected significantly. In the PS group, both the ApoE3 and ApoE4 carriers had a similar response to PS consumption. These findings suggested that PS-fortified soy milk powder was effective in lowering the serum cholesterol levels in older Chinese volunteers with mild to moderate hypercholesterolemia in both the ApoE3 and ApoE4 carriers.

  14. Soy milk powder supplemented with phytosterol esters reduced serum cholesterol level in hypercholesterolemia independently of lipoprotein E genotype: a random clinical placebo-controlled trial.

    PubMed

    Dong, Shan; Zhang, Ran; Ji, Ya-Cheng; Hao, Jia-Yin; Ma, Wei-Wei; Chen, Xu-Dong; Xiao, Rong; Yu, Huan-Ling

    2016-08-01

    Phytosterols (PSs) are reported to lower the serum total cholesterol and low-density lipoprotein cholesterol concentrations enriched in some fatty foods, such as margarine. However, these high-fat foods are not very suitable for older people. Soy milk is the favorite food for elderly people in China; therefore, we hypothesized that the consumption of soy milk powder supplemented with PSs would decrease the serum cholesterol levels in older Chinese people independent of the genotypes of apolipoprotein E (ApoE). Mild to moderate hyperlipidemic patients (n = 170) were recruited from different communities and treated with placebo soy milk powder or 3.4 g PS esters-enriched soy milk powder (2.0 g/d free PS in 30 g soy milk powder). The fasting serum lipid profiles at the baseline and after 3 and 6 months of intervention were measured. The ApoE genotype was also determined. After 3 months of PS intervention, the serum lipid profile was not changed significantly in either group. The serum total cholesterol, low-density lipoprotein cholesterol, and non- high-density lipoprotein cholesterol levels decreased by 9.3%, 11.4%, and 12.6%, respectively, in the PS group at the end of the intervention (6 months) compared with the control group, whereas the serum high-density lipoprotein cholesterol and triglyceride levels were not affected significantly. In the PS group, both the ApoE3 and ApoE4 carriers had a similar response to PS consumption. These findings suggested that PS-fortified soy milk powder was effective in lowering the serum cholesterol levels in older Chinese volunteers with mild to moderate hypercholesterolemia in both the ApoE3 and ApoE4 carriers. PMID:27440543

  15. Interaction of high-density and low-density lipoproteins to solid surfaces coated with cholesterol as determined by an optical fiber-based biosensor

    NASA Astrophysics Data System (ADS)

    Singh, Bal R.; Poirier, Michelle A.

    1993-05-01

    In recent years, the use of fiber optics has become an important tool in biomedicine and biotechnology. We are involved in developing and employing a new system which, through the use of fiber optics, may be capable of measuring the content of cholesterol and lipoproteins in blood samples in real time. In the optical fiber-based biosensor, a laser beam having a wavelength of 512 nm (green light) is launched into an optical fiber, which transmits the light to its distal end. An evanescent wave (travelling just outside the fiber core) is used to excite rhodamine-labelled HDL or LDL which become bound to the fiber or to fiber-bound molecules. The fluorescence (red light) is coupled back into the fiber and detected with a photodiode. Preliminary work has involved testing of high density lipoprotein (HDL) binding to a cholesterol-coated fiber and to a bare fiber and low density lipoprotein (LDL) binding to a cholesterol-coated fiber. A significant difference was observed in the binding rate of HDL (5 (mu) g/mL and lower) to a bare fiber as opposed to a cholesterol-coated fiber. The binding rate of HDL (5 (mu) g/mL) to a bare fiber was 7.5 (mu) V/sec and to a cholesterol-coated fiber was 3.5 (mu) V/sec. We have calculated the binding affinity of LDL to a cholesterol- coated fiber as 1.4 (mu) M-1. These preliminary results suggest that the optical fiber-based biosensor can provide a unique and promising approach to the analysis of lipoprotein interaction with solid surfaces and with cholesterol. More importantly, the results suggest that this technique may be used to assess the binding of blood proteins to artificial organs/tissues, and to measure the amount of cholesterol, HDL and LDL in less than a minute.

  16. Low high-density lipoprotein cholesterol is a residual risk factor associated with long-term clinical outcomes in diabetic patients with stable coronary artery disease who achieve optimal control of low-density lipoprotein cholesterol.

    PubMed

    Ogita, Manabu; Miyauchi, Katsumi; Miyazaki, Tadashi; Naito, Ryo; Konishi, Hirokazu; Tsuboi, Shuta; Dohi, Tomotaka; Kasai, Takatoshi; Yokoyama, Takayuki; Okazaki, Shinya; Kurata, Takeshi; Daida, Hiroyuki

    2014-01-01

    Diabetes mellitus is recognized an independent risk factor for coronary artery disease (CAD) and mortality. Clinical trials have shown that statins significantly reduce cardiovascular events in diabetic patients. However, residual cardiovascular risk persists despite the achievement of target low-density lipoprotein cholesterol (LDL-C) levels with statin. High-density lipoprotein cholesterol (HDL-C) is an established coronary risk factor that is independent of LDL-C levels. We evaluated the impact of HDL-C on long-term mortality in diabetic patients with stable CAD who achieved optimal LDL-C. We enrolled 438 consecutive diabetic patients who were scheduled for percutaneous coronary intervention between 2004 and 2007 at our institution. We identified 165 patients who achieved target LDL-C <100 mg/dl. Patients were stratified into two groups according to HDL-C levels (low HDL-C group, baseline HDL-C <40 mg/dl; high HDL-C group, ≥40 mg/dl). Major adverse cardiac events (MACE) that included all-cause death, acute coronary syndrome, and target lesion revascularization were evaluated between the two groups. The median follow-up period was 946 days. The rate of MACE was significantly higher in diabetic patients with low-HDL-C who achieved optimal LDL-C (6.9 vs 17.9 %, log-rank P = 0.030). Multivariate Cox regression analysis showed that HDL-C is significantly associated with clinical outcomes (adjusted hazard ratio for MACE 1.33, 95 % confidence interval 1.01-1.75, P = 0.042). Low HDL-C is a residual risk factor that is significantly associated with long-term clinical outcomes among diabetic patients with stable CAD who achieve optimal LDL-C levels.

  17. Extended-Release Niacin Versus Fenofibrate in HIV-Infected Participants With Low High-Density Lipoprotein Cholesterol: Effects on Endothelial Function, Lipoproteins, and Inflammation

    PubMed Central

    Dubé, Michael P.; Komarow, Lauren; Fichtenbaum, Carl J.; Cadden, Joseph J.; Overton, Edgar T.; Hodis, Howard N.; Currier, Judith S.; Stein, James H.

    2015-01-01

    Background. Low levels of high-density lipoprotein cholesterol (HDL-C) are common in individuals with human immunodeficiency virus (HIV) infection, persist during antiretroviral therapy (ART), and are associated with increased cardiovascular disease (CVD) risk. Methods. Virologically controlled participants without CVD on stable ART with low HDL-C (men <40 mg/dL, women <50 mg/dL) and triglycerides >150 mg/dL were randomized to receive open-label extended-release niacin 1500 mg/day with aspirin 325 mg/day or fenofibrate 200 mg/day for 24 weeks. The primary endpoint was the week 24 within-arm change in brachial artery flow-mediated dilation (FMD) in participants with complete follow-up scans. Results. Of 99 participants, 74 had complete data (35 niacin, 39 fenofibrate). Median age was 45 years, 77% were male, median CD4+ count was 561 cells/µL, and brachial FMD was 4.2%. Median HDL-C was 32 mg/dL for men and 38 mg/dL for women, low-density lipoprotein cholesterol was 103 mg/dL, and triglycerides were 232 mg/dL. In men, HDL-C increased a median of 3 mg/dL with niacin and 6.5 mg/dL with fenofibrate (P < .001 for both). In women, HDL-C increased a median of 16 mg/dL with niacin and 8 mg/dL with fenofibrate (P = .08 for both). After 24 weeks, there was no significant change in FMD in either arm; the median (interquartile range) change was +0.6% (−1.6 to 2.3) with niacin (P = .28) and +0.5% (−1.0 to 3.0) with fenofibrate (P = .19). Neither treatment significantly affected C-reactive protein, interleukin 6, or D-dimer levels. Conclusions. Despite improvements in lipids, niacin or fenofibrate treatment for 24 weeks did not improve endothelial function or inflammatory markers in participants with well-controlled HIV infection and low HDL-C. Clinical Trials Registration. NCT01426438. PMID:25979307

  18. Comparison of effects of ezetimibe/simvastatin versus simvastatin versus atorvastatin in reducing C-reactive protein and low-density lipoprotein cholesterol levels.

    PubMed

    Pearson, Thomas; Ballantyne, Christie; Sisk, Christine; Shah, Arvind; Veltri, Enrico; Maccubbin, Darbie

    2007-06-15

    The lowering effects of ezetimibe/simvastatin combination therapy on low-density lipoprotein (LDL) cholesterol and high-sensitivity C-reactive protein (CRP) were compared with those of simvastatin or atorvastatin monotherapy in a large cohort of patients with primary hypercholesterolemia. To compare ezetimibe/simvastatin with simvastatin, data were combined from 3 identical, prospective 12-week trials in which patients were randomized to receive placebo; ezetimibe 10 mg; ezetimibe 10 mg added to simvastatin 10, 20, 40, or 80 mg; or simvastatin 10, 20, 40, or 80 mg. To compare ezetimibe/simvastatin with atorvastatin, data were analyzed from a phase III double-blind, active-controlled study in which patients were randomized equally to receive ezetimibe/simvastatin 10/10, 10/20, 10/40, or 10/80 mg or atorvastatin 10, 20, 40, or 80 mg for 6 weeks. When averaged across doses, ezetimibe/simvastatin produced significantly greater reductions compared with simvastatin alone in LDL cholesterol (52.5% vs 38.0%, respectively) and CRP levels (31.0% vs 14.3%, respectively). At each individual simvastatin dose, co-administration with ezetimibe produced significant further CRP reductions versus simvastatin alone. Ezetimibe/simvastatin was significantly more effective at lowering LDL cholesterol than atorvastatin when pooled across doses (53.4% vs 45.3%, respectively) and in each milligram-equivalent dose comparison. Reductions in CRP of similar magnitude were observed with ezetimibe/simvastatin and atorvastatin when averaged across doses and at each milligram-equivalent statin dose comparison. In conclusion, the lipid-modulating and anti-inflammatory effects of ezetimibe/simvastatin provide additional benefits not realized by statin monotherapy alone.

  19. Synthetic High-Density Lipoprotein-Like Nanocarrier Improved Cellular Transport of Lysosomal Cholesterol in Human Sterol Carrier Protein-Deficient Fibroblasts.

    PubMed

    Nam, Da-Eun; Kim, Ok-Kyung; Park, Yoo Kyoung; Lee, Jeongmin

    2016-01-01

    Sterol carrier protein-2 (SCP-2), which is not found in tissues of people with Zellweger syndrome, facilitates the movement of cholesterol within cells, resulting in abnormal accumulation of cholesterol in SCP-2-deficient cells. This study investigated whether synthetic high-density lipoprotein-like nanocarrier (sHDL-NC) improves the cellular transport of lysosomal cholesterol to plasma membrane in SCP-2-deficient fibroblasts. Human SCP-2-deficient fibroblasts were incubated with [(3)H-cholesterol]LDL as a source of cholesterol and sHDL-NC. The cells were fractionated by centrifugation permit tracking of [(3)H]-cholesterol from lysosome into plasma membrane. Furthermore, cellular content of cholesteryl ester as a storage form and mRNA expression of low-density lipoprotein (LDL) receptor were measured to support the cholesterol transport to plasma membrane. Incubation with sHDL-NC for 8 h significantly increased uptake of [(3)H]-cholesterol to lysosome by 53% and further enhanced the transport of [(3)H]-cholesterol to plasma membrane by 32%. Treatment with sHDL-NC significantly reduced cellular content of cholesteryl ester and increased mRNA expression of LDL receptor (LDL-R). In conclusion, sHDL-NC enables increased transport of lysosomal cholesterol to plasma membrane. In addition, these data were indirectly supported by decreased cellular content of cholesteryl ester and increased gene expression of LDL-R. Therefore, sHDL-NC may be a useful vehicle for transporting cholesterol, which may help to prevent accumulation of cholesterol in SCP-2-deficient fibroblasts.

  20. 27-Hydroxycholesterol contributes to disruptive effects on learning and memory by modulating cholesterol metabolism in the rat brain.

    PubMed

    Zhang, D-D; Yu, H-L; Ma, W-W; Liu, Q-R; Han, J; Wang, H; Xiao, R

    2015-08-01

    Cholesterol metabolism is important for neuronal function in the central nervous system (CNS). The oxysterol 27-hydroxycholesterol (27-OHC) is a cholesterol metabolite that crosses the blood-brain barrier (BBB) and may be a useful substitutive marker for neurodegenerative diseases. However, the effects of 27-OHC on learning and memory and the underlying mechanisms are unclear. To determine this mechanism, we investigated learning and memory and cholesterol metabolism in rat brain following the injection of various doses of 27-OHC into the caudal vein. We found that 27-OHC increased cholesterol levels and upregulated the expression of liver X receptor-α (LXR-α) and adenosine triphosphate (ATP)-binding cassette transporter protein family member A1 (ABCA1). In addition, 27-OHC decreased the expression of 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-CR) and low-density lipoprotein receptor (LDLR) in rat brain tissues. These findings suggest that 27-OHC may negatively modulate cognitive effects and cholesterol metabolism in the brain.

  1. [Cholesterol of the high-density lipoprotein subclasses in the native inhabitants of the Chukchi National Autonomous Okrug].

    PubMed

    Polesskiĭ, V A; Chepurnenko, N V; Koshechkin, V A; Morozov, V V; Gerasimova, E N

    1980-12-01

    The authors studied the content of total cholesterol (Ch), triglycerides (TG), CS of high density lipoprotein (HDL2 and HDL3) subclasses and testosterone in blood plasma of 30-59-year-old males, natives or newcomers of Chukotsk, and compared the results with the corresponding values determined in the male population of Moscow. It was established that the mean HDL Ch concentration in blood plasma was higher and the content of TG and to a lesser degree that of total CS, was lower in the Chukchi males than in the male Moscow population and in the newcomers who were examined. It was also shown that in hypo- and hyper-alphalipoproteinemia in all groups examined, the content of HDL2 Ch changed for the most part (decreased or increased, respectively) while the level of HDL3 Ch remained relatively stable.

  2. Effects of a 12-week healthy-life exercise program on oxidized low-density lipoprotein cholesterol and carotid intima-media thickness in obese elderly women.

    PubMed

    Park, Jong-Hwan; Park, Hyuntae; Lim, Seung-Taek; Park, Jin-Kee

    2015-05-01

    [Purpose] This study examined the effects of a 12-week exercise program on plasma level of oxidized low-density lipoprotein cholesterol in obese elderly women, who are at increased risk of heart disease morbidity. [Subjects and Methods] Twenty participants were assigned into either a control (n = 10) or a supervised exercise program (n = 10) group. The 12-week exercise intervention was performed 3 days per week and involved combined aerobic exercise, resistance exercise, and traditional Korean dance. [Results] Two-factor analysis of variance revealed significant group × time interactions for body mass, diastolic blood pressure, appendicular muscle mass. For high-density lipoprotein cholesterol, oxidized low-density lipoprotein cholesterol, and the ratio of oxidized low-/high-density lipoprotein cholesterol, two-factor analysis of variance revealed significant interactions (group × time), indicating responses differed significantly between the control and exercise groups after 12 weeks. [Conclusion] A 12-week low- to moderate-intensity exercise program appears to be beneficial for obese elderly women by improving risk factors for cardiovascular disease.

  3. The Effect of Aerobic Exercise on Total Cholesterol, High-Density Lipoprotein, Apolipoprotein B, Apolipoprotein A-I, and Percent Body Fat in Adolescent Females.

    ERIC Educational Resources Information Center

    Lungo, Diane; And Others

    The effect of aerobic exercise on total cholesterol (TC), high-density lipoprotein (HDL), apolipoprotein B (Apo B), apolioprotein A-I (Apo A-I), and percent body fat in adolescent females was studied. The control subjects (n=86) were volunteers who had completed a physical education class at least six months prior to the commencement of the study,…

  4. Genetic variation at the SLCO1B1 gene locus and low density lipoprotein cholesterol lowering response to pravastatin in the elderly

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our goal was to determine whether genetic variation at genes affecting statin metabolism or targets of statin therapy would influence low density lipoprotein (LDL) cholesterol lowering with pravastatin, baseline heart disease, or cardiac endpoints on trial. We examined associations of single nucleot...

  5. Rates of cholesterol synthesis and low-density lipoprotein uptake in the adrenal glands of the rat, hamster and rabbit in vivo.

    PubMed

    Spady, D K; Dietschy, J M

    1985-09-11

    The absolute rate of cholesterol acquisition from de novo synthesis and from receptor-dependent and receptor-independent low-density lipoprotein (LDL) uptake was determined in the adrenal glands of the rat, hamster and rabbit under in vivo conditions. The rate of incorporation of [3H]water into cholesterol in the adrenal gland was much higher in the hamster (1727 nmol/h per g) and rabbit (853 nmol/h per g) than in the rat (71 nmol/h per g). Assuming that 23 atoms of 3H are incorporated into the cholesterol molecule during its biosynthesis, the absolute rates of cholesterol synthesis were then calculated to equal 59, 29 and 2.4 micrograms/h per g of adrenal gland in the hamster, rabbit and rat, respectively. Rates of LDL-cholesterol uptake were measured using a primed continuous infusion of [14C]sucrose-labeled homologous LDL (total LDL transport) and methylated human LDL (receptor-independent LDL transport). The rate of total LDL-cholesterol uptake in the adrenal gland was much higher in the rabbit (227 micrograms/h per g) than in the rat (18 micrograms/h per g) or hamster (6 micrograms/h per g). In all three species LDL uptake was mediated largely (greater than 93%) by receptor-dependent mechanisms. In terms of total cholesterol acquisition, the hamster adrenal gland derived 10-times more cholesterol from de novo synthesis than from LDL uptake, whereas the converse was true in the rabbit. Rates of de novo synthesis and LDL-cholesterol uptake were both low in the rat adrenal gland, which is known to derive cholesterol mainly from circulating high-density lipoproteins. Thus, the adrenal gland acquires cholesterol for hormone synthesis from at least three different sources and the quantitative importance of these sources varies markedly in different animal species, including man. PMID:2992599

  6. Small dense low density lipoprotein cholesterol and coronary heart disease: results from the Framingham Offspring Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We sought to establish reference values for a new direct assay for small dense LDL cholesterol (sdLDL-C) and to measure sdLDL-C concentrations in patients with established coronary heart disease (CHD) vs controls. Direct LDL-C and sdLDL-C were measured in samples from 3188 male and female participan...

  7. Modulation of gut microbiota by polyphenols from adlay (Coix lacryma-jobi L. var. ma-yuen Stapf.) in rats fed a high-cholesterol diet.

    PubMed

    Wang, Qingyu; Du, Zhongyao; Zhang, Hao; Zhao, Liang; Sun, Jing; Zheng, Xiaonan; Ren, Fazheng

    2015-01-01

    This study aimed to evaluate the beneficial effects of polyphenol extract of adlay (Coix lacryma-jobi L. var. ma-yuen Stapf.) (PEA) on gut microbiota in rats fed a high-cholesterol diet (HCD). Rats were fed HCD containing 1% cholesterol (w/w), with or without a daily intragastric supplement of 200 mg/kg body weight PEA. Results showed that PEA significantly ameliorated increases in serum cholesterol and low-density lipoprotein cholesterol values and significantly restored high-density lipoprotein cholesterol values. The HCD-induced imbalance of gut microflora was modulated by the consumption of PEA. Most bacterial strains influenced by PEA are related to host lipid metabolism. The abundances of one Erysipelotrichales strains and two Clostridia strains were lower in the PEA group than in the control. Phenolic compounds in PEA were identified by HPLC. The findings indicate that PEA may be a useful dietary supplement in the treatment of elevated cholesterol levels and the imbalanced gut microbial ecology.

  8. Effect of ezetimibe/atorvastatin combination on oxidized low density lipoprotein cholesterol in patients with coronary artery disease or coronary artery disease equivalent.

    PubMed

    Azar, Rabih R; Badaoui, Georges; Sarkis, Antoine; Azar, Mireille; Aydanian, Herminé; Harb, Serge; Achkouty, Guy; Kassab, Roland

    2010-07-15

    Ezetimibe is effective in providing additional low-density lipoprotein (LDL) cholesterol lowering when coadministered with statins, but its effect beyond LDL cholesterol lowering is unknown. Oxidized LDL (ox-LDL) is a better predictor of adverse cardiovascular events than standard lipid parameters. The objective of this study was to investigate the effect of ezetimibe on ox-LDL. A total of 100 patients with coronary artery disease or coronary artery disease equivalent were randomized to atorvastatin 40 mg/day and ezetimibe 10 mg/day or to atorvastatin 40 mg/day and placebo. LDL cholesterol, LDL cholesterol subfractions, and ox-LDL were measured at baseline and after 8 weeks of therapy. The ezetimibe group had a larger reduction in total LDL cholesterol compared to placebo. This was due mainly to a larger reduction in large buoyant LDL (24% vs 10%, p = 0.008). Ox-LDL level did not change in the placebo group (50 +/- 13 vs 51 +/- 13 U/L), while it decreased in the ezetimibe group, from 51 +/- 13 to 46 +/- 10 U/L (p = 0.01 vs baseline and p = 0.02 vs final level in placebo). The change in ox-LDL correlated significantly with those in total LDL and in large buoyant LDL (r = 0.6 and r = 0.5, respectively, p <0.01 for both), but not with that of small dense LDL, high-density lipoprotein, or very low density lipoprotein. In conclusion, this study demonstrates that ezetimibe decreases ox-LDL cholesterol through reductions in total LDL cholesterol and in large buoyant LDL cholesterol.

  9. Switching to black rice diets modulates low-density lipoprotein oxidation and lipid measurements in rabbits.

    PubMed

    Abdel-Moemin, Aly R

    2011-04-01

    The effect of white and black rice consumption on lipid profile, hydroperoxides, thiobarbituric reactive substances and oxidized low-density lipoprotein (LDL) induced by hypercholesterolemia was investigated in 24 male rabbits; a purified normal diet (NC, n = 6), a high fat/cholesterol (1.0 g/100 g) diet (PC group, n = 6), a high fat/cholesterol diet with 25 g/100 g white ground rice (PCWR group, n = 6), 25 g/100 g black ground rice (PCBR group, n = 6) for 10 weeks. Blood samples were collected for lipid measurements. Results indicate that serum high-density lipoprotein-cholesterol was higher (P < 0.05) in the PCBR compared with the PC and PCWR groups. Hydroperoxides and thiobarbituric reactive substances were significantly lower (P < 0.05) in the PCBR compared with PCWR and PC groups. Cyanidin-3-glucoside (Cy-3-Glu) and peonidin-3-glucoside have been tested in vitro against copper-mediated low-density lipoprotein. Cy-3-Glu was excelled peonidin-3-glucoside by increasing the lag time of NC from 80 to 500 minutes in the presence of 2.0 μM of Cy-3-Glu. Hierarchically, black rice rabbits group was given the best results compared with other groups. The results may be indicating to a suggested mechanism (anthocyanins protection; Cy-3-Glu) of the cardioprotective effect of black rice. PMID:21289511

  10. Multiple Hepatic Regulatory Variants at the GALNT2 GWAS Locus Associated with High-Density Lipoprotein Cholesterol

    PubMed Central

    Roman, Tamara S.; Marvelle, Amanda F.; Fogarty, Marie P.; Vadlamudi, Swarooparani; Gonzalez, Arlene J.; Buchkovich, Martin L.; Huyghe, Jeroen R.; Fuchsberger, Christian; Jackson, Anne U.; Wu, Ying; Civelek, Mete; Lusis, Aldons J.; Gaulton, Kyle J.; Sethupathy, Praveen; Kangas, Antti J.; Soininen, Pasi; Ala-Korpela, Mika; Kuusisto, Johanna; Collins, Francis S.; Laakso, Markku; Boehnke, Michael; Mohlke, Karen L.

    2015-01-01

    Genome-wide association studies (GWASs) have identified more than 150 loci associated with blood lipid and cholesterol levels; however, the functional and molecular mechanisms for many associations are unknown. We examined the functional regulatory effects of candidate variants at the GALNT2 locus associated with high-density lipoprotein cholesterol (HDL-C). Fine-mapping and conditional analyses in the METSIM study identified a single locus harboring 25 noncoding variants (r2 > 0.7 with the lead GWAS variants) strongly associated with total cholesterol in medium-sized HDL (e.g., rs17315646, p = 3.5 × 10−12). We used luciferase reporter assays in HepG2 cells to test all 25 variants for allelic differences in regulatory enhancer activity. rs2281721 showed allelic differences in transcriptional activity (75-fold [T] versus 27-fold [C] more than the empty-vector control), as did a separate 780-bp segment containing rs4846913, rs2144300, and rs6143660 (49-fold [AT– haplotype] versus 16-fold [CC+ haplotype] more). Using electrophoretic mobility shift assays, we observed differential CEBPB binding to rs4846913, and we confirmed this binding in a native chromatin context by performing chromatin-immunoprecipitation (ChIP) assays in HepG2 and Huh-7 cell lines of differing genotypes. Additionally, sequence reads in HepG2 DNase-I-hypersensitivity and CEBPB ChIP-seq signals spanning rs4846913 showed significant allelic imbalance. Allelic-expression-imbalance assays performed with RNA from primary human hepatocyte samples and expression-quantitative-trait-locus (eQTL) data in human subcutaneous adipose tissue samples confirmed that alleles associated with increased HDL-C are associated with a modest increase in GALNT2 expression. Together, these data suggest that at least rs4846913 and rs2281721 play key roles in influencing GALNT2 expression at this HDL-C locus. PMID:26637976

  11. Multiple Hepatic Regulatory Variants at the GALNT2 GWAS Locus Associated with High-Density Lipoprotein Cholesterol.

    PubMed

    Roman, Tamara S; Marvelle, Amanda F; Fogarty, Marie P; Vadlamudi, Swarooparani; Gonzalez, Arlene J; Buchkovich, Martin L; Huyghe, Jeroen R; Fuchsberger, Christian; Jackson, Anne U; Wu, Ying; Civelek, Mete; Lusis, Aldons J; Gaulton, Kyle J; Sethupathy, Praveen; Kangas, Antti J; Soininen, Pasi; Ala-Korpela, Mika; Kuusisto, Johanna; Collins, Francis S; Laakso, Markku; Boehnke, Michael; Mohlke, Karen L

    2015-12-01

    Genome-wide association studies (GWASs) have identified more than 150 loci associated with blood lipid and cholesterol levels; however, the functional and molecular mechanisms for many associations are unknown. We examined the functional regulatory effects of candidate variants at the GALNT2 locus associated with high-density lipoprotein cholesterol (HDL-C). Fine-mapping and conditional analyses in the METSIM study identified a single locus harboring 25 noncoding variants (r(2) > 0.7 with the lead GWAS variants) strongly associated with total cholesterol in medium-sized HDL (e.g., rs17315646, p = 3.5 × 10(-12)). We used luciferase reporter assays in HepG2 cells to test all 25 variants for allelic differences in regulatory enhancer activity. rs2281721 showed allelic differences in transcriptional activity (75-fold [T] versus 27-fold [C] more than the empty-vector control), as did a separate 780-bp segment containing rs4846913, rs2144300, and rs6143660 (49-fold [AT(-) haplotype] versus 16-fold [CC(+) haplotype] more). Using electrophoretic mobility shift assays, we observed differential CEBPB binding to rs4846913, and we confirmed this binding in a native chromatin context by performing chromatin-immunoprecipitation (ChIP) assays in HepG2 and Huh-7 cell lines of differing genotypes. Additionally, sequence reads in HepG2 DNase-I-hypersensitivity and CEBPB ChIP-seq signals spanning rs4846913 showed significant allelic imbalance. Allelic-expression-imbalance assays performed with RNA from primary human hepatocyte samples and expression-quantitative-trait-locus (eQTL) data in human subcutaneous adipose tissue samples confirmed that alleles associated with increased HDL-C are associated with a modest increase in GALNT2 expression. Together, these data suggest that at least rs4846913 and rs2281721 play key roles in influencing GALNT2 expression at this HDL-C locus. PMID:26637976

  12. Relationship of High‐Density Lipoprotein Cholesterol With Periprocedural Myocardial Injury Following Elective Percutaneous Coronary Intervention in Patients With Low‐Density Lipoprotein Cholesterol Below 70 mg/dL

    PubMed Central

    Li, Xiao‐Lin; Guo, Yuan‐Lin; Zhu, Cheng‐Gang; Xu, Rui‐Xia; Qing, Ping; Wu, Na‐Qiong; Jiang, Li‐Xin; Xu, Bo; Gao, Run‐Lin; Li, Jian‐Jun

    2015-01-01

    Background Recent data showed inconsistent association of high‐density lipoprotein cholesterol (HDL‐C) with cardiovascular risk in patients with different levels of low‐density lipoprotein cholesterol (LDL‐C) or intensive statin therapy. This study sought to determine the relationship of HDL‐C with periprocedural myocardial injury following elective percutaneous coronary intervention (PCI) across a range of LDL‐C levels, especially in patients with LDL‐C <70 mg/dL. Methods and Results We enrolled 2529 consecutive patients with normal preprocedural cardiac troponin I (cTnI) who underwent elective PCI. The association between preprocedural HDL‐C and periprocedural myocardial injury was evaluated across LDL‐C levels, especially in patients with LDL‐C <70 mg/dL. The HDL‐C level was not predictive of periprocedural myocardial injury across the entire study cohort. However, among patients with LDL‐C <70 mg/dL, a 1 mg/dL increase in HDL‐C was associated with a 3% reduced risk for postprocedural cTnI above 1×upper limit of normal (ULN) (odds ratio: 0.97; 95% CI: 0.95 to 0.99; P=0.004), a 3% reduced risk for postprocedural cTnI above 3×ULN odds ratio: 0.97; 95% CI: 0.95 to 0.99; P=0.022), and a 3% reduced risk for postprocedural cTnI above 5×ULN (odds ratio: 0.97; 95% CI: 0.95 to 0.99; P=0.017). The relation between plasma HDL‐C level and risk of postprocedural cTnI elevation above 1×ULN, 3×ULN, and 5×ULN was modified by LDL‐C level (all P for interaction <0.05). Conclusions Higher HDL‐C levels were associated with reduced risk of periprocedural myocardial injury only in patients with LDL‐C <70 mg/dL. PMID:25572484

  13. Pharmacogenetic interaction between dexamethasone and Cd36-deficient segment of spontaneously hypertensive rat chromosome 4 affects triacylglycerol and cholesterol distribution into lipoprotein fractions.

    PubMed

    Krupková, Michaela; Sedová, Lucie; Liska, Frantisek; Krenová, Drahomíra; Kren, Vladimír; Seda, Ondrej

    2010-04-16

    Dexamethasone (DEX) is known to induce diabetes and dyslipidemia. We have compared fasting triacylglycerol and cholesterol concentrations across 20 lipoprotein fractions and glucose tolerance in control (standard diet) and DEX-treated 7-month-old males of two rat strains, Brown Norway (BN) and congenic BN.SHR-(Il6-Cd36)/Cub (BN.SHR4). These two inbred strains differ in a defined segment of chromosome 4, originally transferred from the spontaneously hypertensive rat (SHR) including the mutant Cd36 gene, a known target of DEX. Compared to BN, the standard-diet-fed BN.SHR4 showed higher cholesterol and triacylglycerol concentrations across many lipoprotein fractions, particularly in small VLDL and LDL particles. Total cholesterol was decreased by DEX by more than 21% in BN.SHR4 contrasting with the tendency to increase in BN (strain*DEX interaction p = 0.0017). Similar pattern was observed for triacylglycerol concentrations in LDL. The LDL particle size was significantly reduced by DEX in both strains. Also, while control BN and BN.SHR4 displayed comparable glycaemic profiles during oral glucose tolerance test, we observed a markedly blunted DEX induction of glucose intolerance in BN.SHR4 compared to BN. In summary, we report a pharmacogenetic interaction between limited genomic segment with mutated Cd36 gene and dexamethasone-induced glucose intolerance and triacylglycerol and cholesterol redistribution into lipoprotein fractions.

  14. High density lipoprotein as a source of cholesterol for adrenal steroidogenesis: a study in individuals with low plasma HDL-C.

    PubMed

    Bochem, Andrea E; Holleboom, Adriaan G; Romijn, Johannes A; Hoekstra, Menno; Dallinga-Thie, Geesje M; Motazacker, Mahdi M; Hovingh, G Kees; Kuivenhoven, Jan A; Stroes, Erik S G

    2013-06-01

    Few studies have addressed the delivery of lipoprotein-derived cholesterol to the adrenals for steroid production in humans. While there is evidence against a role for low-density lipoprotein (LDL), it is unresolved whether high density lipoprotein (HDL) contributes to adrenal steroidogenesis. To study this, steroid hormone profiles in urine were assessed in male subjects suffering from functional mutations in ATP binding cassette transporter A1 (ABCA1) (n = 24), lecithin:cholesterol acyltransferase (LCAT) (n = 40), as well as in 11 subjects with low HDL cholesterol (HDL-C) without ABCA1/LCAT mutations. HDL-C levels were 39% lower in the ABCA1, LCAT, and low HDL-C groups compared with controls (all P < 0.001). In all groups with low HDL-C levels, urinary excretion of 17-ketogenic steroids was reduced by 33%, 27%, and 32% compared with controls (all P < 0.04). In seven carriers of either type of mutation, adrenocorticotropic hormone (ACTH) stimulation did not reveal differences from normolipidemic controls. In conclusion, this study shows that basal but not stimulated corticosteroid metabolism is attenuated in subjects with low HDL-C, irrespective of its molecular origin. These findings lend support to a role for HDL as a cholesterol donor for basal adrenal steroidogenesis in humans. PMID:23511897

  15. An interaction between the TaqIB polymorphism of cholesterol ester transfer protein and smoking is associated with changes in plasma high-density lipoprotein cholesterol levels in Turks.

    PubMed

    Hodoğlugil, U; Williamson, D W; Huang, Y; Mahley, R W

    2005-08-01

    Low levels of high-density lipoprotein cholesterol (HDL-C) are an independent risk factor for atherosclerosis. We investigated the effects of the TaqIB polymorphism of cholesterol ester transfer protein (CETP) on CETP activity and plasma HDL-C levels in random nondiabetic and self-reported diabetic subjects in a population with very low HDL-C levels. The rare B2B2 genotype was associated with significantly higher HDL-C levels and lower CETP activity in random subjects and with higher HDL-C in diabetic subjects. After stratification of random subjects by smoking status, the common B1B1 genotype was associated with lower HDL-C levels than the B2B2 genotype. Although smoking was associated with lower HDL-C, especially in men, HDL-C levels between smokers and nonsmokers were not different in subjects with the B1B2 or B2B2 genotypes. However, smoking (20+ cigarettes/day) was associated with a marked reduction in HDL-C in the B1B1 subjects. The B1B1/smoking interaction was not reflected in a difference in CETP activity. High triglycerides and elevated body mass index (BMI) lower HDL-C. The B2B2 genotype was associated with the highest HDL-C levels, and these levels were significantly lower in the hypertriglyceridemic subjects (>or=50th percentile). The lowest HDL-C levels were seen in hypertriglyceridemic subjects with the B1B1 genotype. Although BMI (>or=50th vs<50th percentile) did not affect HDL-C in B2B2 subjects, a high BMI was associated with markedly lower HDL-C in B1B1 subjects. Thus, HDL-C levels in Turks may be modulated by an interaction between the CETP TaqIB polymorphism and smoking, as well as an interaction with hypertriglyceridemia and BMI.

  16. Antioxidative Activity after Rosuvastatin Treatment in Patients with Stable Ischemic Heart Disease and Decreased High Density Lipoprotein Cholesterol

    PubMed Central

    Park, Do-Sim; Park, Hyun Young; Rhee, Sang Jae; Kim, Nam-Ho; Oh, Seok Kyu; Jeong, Jin-Won

    2016-01-01

    Background and Objectives The clinical significance of statin-induced high-density lipoprotein cholesterol (HDL-C) changes is not well known. We investigated whether rosuvastatin-induced HDL-C changes can influence the anti-oxidative action of high-density lipoprotein particle. Subjects and Methods A total of 240 patients with stable ischemic heart disease were studied. Anti-oxidative property was assessed by paraoxonase 1 (PON1) activity. We compared the lipid profile and PON1 activity at baseline and at 8 weeks after rosuvastatin 10 mg treatment. Results Rosuvastatin treatment increased the mean HDL-C concentration by 1.9±9.2 mg/dL (6.4±21.4%). HDL-C increased in 138 patients (57.5%), but decreased in 102 patients (42.5%) after statin treatment. PON1 activity increased to 19.1% in all patients. In both, the patients with increased HDL-C and with decreased HDL-C, PON1 activity significantly increased after rosuvastatin treatment (+19.3% in increased HDL-C responder; p=0.018, +18.8% in decreased HDL-C responder; p=0.045 by paired t-test). Baseline PON1 activity modestly correlated with HDL-C levels (r=0.248, p=0.009); however, the PON1 activity evaluated during the course of the treatment did not correlate with HDL-C levels (r=0.153, p=0.075). Conclusion Rosuvastatin treatment improved the anti-oxidative properties as assessed by PON1 activity, regardless of on-treatment HDL-C levels, in patients with stable ischemic heart disease. PMID:27275167

  17. Intrauterine growth restriction combined with a maternal high-fat diet increases hepatic cholesterol and low-density lipoprotein receptor activity in rats.

    PubMed

    Zinkhan, Erin K; Zalla, Jennifer M; Carpenter, Jeanette R; Yu, Baifeng; Yu, Xing; Chan, Gary; Joss-Moore, Lisa; Lane, Robert H

    2016-07-01

    Intrauterine growth restriction (IUGR) and maternal consumption of a high-saturated-fat diet (HFD) increase the risk of hypercholesterolemia, a leading cause of morbidity and mortality. Many pregnant women eat a HFD, thus exposing the fetus to a HFD in utero. The cumulative effect of in utero exposure to IUGR and a HFD on offspring cholesterol levels remains unknown. Furthermore, little is known about the mechanism through which IUGR and maternal HFD consumption increase cholesterol. We hypothesize that IUGR combined with a maternal HFD would increase offspring serum and hepatic cholesterol accumulation via alteration in levels of key proteins involved in cholesterol metabolism. To test our hypothesis we used a rat model of surgically induced IUGR and fed the dams a regular diet or a HFD HFD-fed dams consumed the same kilocalories as regular diet-fed dams, with no difference between surgical intervention groups. In the offspring, IUGR combined with a maternal HFD increased hepatic cholesterol levels, low-density lipoprotein (LDL) receptor protein levels, and Ldlr activity in female rat offspring at birth and both sexes at postnatal day 14 relative to non-IUGR offspring both from regular diet- and HFD-fed dams. These findings suggest that IUGR combined with a maternal HFD increases hepatic cholesterol accumulation via increased LDL cholesterol uptake into the liver with resulting persistent increases in hepatic cholesterol accumulation.

  18. Achieving cholesterol targets by individualizing starting doses of statin according to baseline low-density lipoprotein cholesterol and coronary artery disease risk category: The CANadians Achieve Cholesterol Targets Fast with Atorvastatin Stratified Titration (CanACTFAST) study

    PubMed Central

    Ur, Ehud; Langer, Anatoly; Rabkin, Simon W; Calciu, Cristina-Dana; Leiter, Lawrence A

    2010-01-01

    BACKGROUND: Despite an increasing body of evidence on the benefit of lowering elevated levels of low-density lipoprotein cholesterol (LDL-C), there is still considerable concern that patients are not achieving target LDL-C levels. OBJECTIVE: The CANadians Achieve Cholesterol Targets Fast with Atorvastatin Stratified Titration (CanACTFAST) trial tested whether an algorithm-based statin dosing approach would enable patients to achieve LDL-C and total cholesterol/high-density lipoprotein cholesterol (TC/HDL-C) ratio targets quickly. METHODS: Subjects requiring statin therapy, but with an LDL-C level of 5.7 mmol/L or lower, and triglycerides of 6.8 mmol/L or lower at screening participated in the 12-week study, which had two open-label, six-week phases: a treatment period during which patients received 10 mg, 20 mg, 40 mg or 80 mg of atorvastatin based on an algorithm incorporating baseline LDL-C value and cardiovascular risk; and patients who achieved both LDL-C and TC/HDL-C ratio targets at six weeks continued on the same atorvastatin dose. Patients who did not achieve both targets received dose uptitration using a single-step titration regimen. The primary efficacy outcome was the proportion of patients achieving target LDL-C levels after 12 weeks. RESULTS: Of 2016 subjects screened at 88 Canadian sites, 1258 were assigned to a study drug (1101 were statin-free and 157 were statin-treated at baseline). The proportion of subjects who achieved LDL-C targets after 12 weeks of treatment was 86% (95% CI 84% to 88%) for statin-free patients and 54% (95% CI 46% to 61%) for statin-treated patients. Overall, 1003 subjects (80%; 95% CI 78% to 82%) achieved both lipid targets. CONCLUSIONS: Algorithm-based statin dosing enables patients to achieve LDL-C and TC/HDL-C ratio targets quickly, with either no titration or a single titration. PMID:20151053

  19. Effects of eicosapentaenoic acid and docosahexaenoic acid on low-density lipoprotein cholesterol and other lipids: a review.

    PubMed

    Jacobson, Terry A; Glickstein, Sara B; Rowe, Jonathan D; Soni, Paresh N

    2012-01-01

    In this exploratory, hypothesis-generating literature review, we evaluated potentially differential effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), and non-HDL-C in published studies of ω-3 fatty acid supplementation or prescription ω-3 fatty acid ethyl esters. Placebo-adjusted changes in mean lipid parameters were compared in randomized, controlled trials in subjects treated for ≥ 4 weeks with DHA or EPA. Of 22 studies identified, 6 compared DHA with EPA directly, 12 studied DHA alone (including 14 DHA-treated groups), and 4 examined EPA alone. In studies directly comparing EPA with DHA, a net increase in LDL-C of 3.3% was observed with DHA (DHA: +2.6%; EPA: -0.7%). In such head-to-head comparative studies, DHA treatment was associated with a net decrease in TG by 6.8% (DHA: -22.4%; EPA: -15.6%); a net increase in non-HDL-C by 1.7% (DHA: -1.2%; EPA -2.9%); and a net increase in HDL-C by 5.9% (DHA: +7.3%; EPA: +1.4%). Increases in LDL-C were also observed in 71% of DHA-alone groups [with demonstrated statistical significance (P < .05) in 67% (8 of 12) DHA-alone studies] but not in any EPA-alone studies. Changes in LDL-C significantly correlated with baseline TG for DHA-treated groups. The range of HDL-C increases documented in DHA-alone vs EPA-alone studies further supports the fact that HDL-C is increased more substantially by DHA than EPA. In total, these findings suggest that DHA-containing supplements or therapies were associated with more significant increases in LDL-C and HDL-C than were EPA-containing supplements or therapies. Future prospective, randomized trials are warranted to confirm these preliminary findings, determine the potential effects of these fatty acids on other clinical outcomes, and evaluate the generalizability of the data to larger and more heterogeneous patient populations. PMID:22264569

  20. Cholesterol and Your Child

    MedlinePlus

    ... traveling together are called lipoproteins . Two kinds — low-density lipoprotein (LDL) and high-density lipoprotein (HDL) — are the ones that most of us have heard about. Low-density lipoproteins , or "bad cholesterol," are the primary cholesterol ...

  1. A Dose-Response Study of the Effects of Dietary Cholesterol on Fasting and Postprandial Lipid and Lipoprotein Metabolism in Healthy Young Men

    PubMed Central

    Ginsberg, Henry N.; Karmally, Wahida; Siddiqui, Maliha; Holleran, Steve; Tall, Alan R.; Rumsey, Steven C.; Deckelbaum, Richard J.; Blaner, William S.; Ramakrishnan, Rajasekhar

    2012-01-01

    Despite many previous studies, controversy remains concerning the effects of dietary cholesterol on plasma cholesterol concentrations. In addition, the focus of previous studies has been fasting lipid and lipoprotein concentrations; there are no published studies with postprandial measurements. We studied the effects of four levels of dietary cholesterol intake on fasting lipid, lipoprotein, and apoprotein levels, as well as postprandial lipid levels, in a group of young, healthy men who were otherwise eating a low-fat, American Heart Association step 1 diet. Twenty young, healthy men completed a randomized, four-way crossover design study to test the effects of an American Heart Association step 1 diet containing 0, 1, 2, or 4 eggs per day. Dietary cholesterol ranged from 128 to 858 mg cholesterol per day. Each diet was eaten for 8 weeks, with a break between diets. Three fasting blood samples were obtained at the end of each diet period. In addition, blood samples were obtained just before and 2, 4, and 6 hours after ingestion of a standard lunch containing the various amounts of egg cholesterol. We also obtained blood 4 and 8 hours after the subjects ingested a standard, high-fat formula. Fasting plasma total cholesterol concentrations increased by 1.47 mg/dL (0.038 mmol/L) for every 100 mg dietary cholesterol added to the diet (P <.001). Low-density lipoprotein (LDL) cholesterol increased in parallel. Responsiveness varied but appeared to be normally distributed. Fasting plasma apoprotein B concentrations increased approximately 10% between the 0- and 4-egg diets and were correlated with changes in total and LDL cholesterol concentrations. Although there was a trend toward a greater response in men with an apoprotein E4 allele, this was not statistically significant. Fasting plasma cholesteryl ester transfer protein levels were higher only on the 4-egg diet, and changes in cholesteryl ester transfer protein levels between the 0- and 4-egg diets correlated with

  2. Cholesterol as a natural probe for free radical-mediated lipid peroxidation in biological membranes and lipoproteins.

    PubMed

    Girotti, Albert W; Korytowski, Witold

    2016-04-15

    We describe a relatively convenient and reliable procedure for assessing the magnitude of free radical-mediated (chain) lipid peroxidation in biological systems. The approach is based on use of radiolabeled cholesterol ([(14)C]Ch) as a probe and determination of well-resolved oxidation intermediates/products ([(14)C]ChOX species), using high performance thin layer chromatography with phorphorimaging detection (HPTLC-PI). In a lipid hydroperoxide-primed liposomal test system treated with ascorbate and a lipophilic iron chelate, the following well-resolved [(14)C]ChOX are detected and quantified: 7α/7β-OOH, 7α/7β-OH, and 5,6-epoxide, their levels increasing with incubation time at 37°C. [(14)C]Ch also serves as an excellent probe for lipid peroxidation in lipoproteins and plasma membranes of mammalian cells. Because this approach utilizes Ch as a natural in situ probe, it eliminates potential artifacts associated with artificial probes such as spin traps and fluorophores. PMID:26778710

  3. Glucuronic acid epimerase is associated with plasma triglyceride and high-density lipoprotein cholesterol levels in Turks.

    PubMed

    Hodoğlugil, Uğur; Williamson, David W; Yu, Yi; Farrer, Lindsay A; Mahley, Robert W

    2011-05-01

    We narrowed chromosome 15q21-23 linkage to plasma high-density lipoprotein cholesterol (HDL-C) levels in Turkish families by fine mapping, then focused on glucuronic acid epimerase (GLCE), a heparan sulfate proteoglycan (HSPG) biosynthesis enzyme. HSPGs participate in lipid metabolism along with apolipoprotein (apo) E. Of 31 SNPs in the GLCE locus, nine analyzed by haplotype were associated with HDL-C and triglyceride levels (permuted p = 0.006 and 0.013, respectively) in families. Of five tagging GLCE SNPs in two cohorts of unrelated subjects, three (rs16952868, rs11631403, and rs3865014) were associated with triglyceride and HDL-C levels in males (nonpermuted p < 0.05). The association was stronger in APOE 2/3 subjects (apoE2 has reduced binding to HSPGs) and reached multiple-testing significance (p < 0.05) in both males and females (n= 2612). Similar results were obtained in the second cohort (n= 1164). Interestingly, at the GLCE locus, bounded by recombination hotspots, Turks had a minor allele frequency of SNPs resembling Chinese more than European ancestry; adjoining regions resembled the European pattern. Studies of glce(+/-) apoe(-/-) mice fed a chow or high-fat diet supported a role for GLCE in lipid metabolism. Thus, SNPs in GLCE are associated with triglyceride and HDL-C levels in Turks, and mouse studies support a role for glce in lipid metabolism.

  4. Reflex Testing for Carbohydrate-Deficient Transferrin (CDT) in Insurance Applicants with Elevated High Density Lipoprotein Cholesterol (HDL).

    PubMed

    Singh, Gurmukh

    2015-01-01

    Objectives .- Ascertain the utility of testing carbohydrate deficient transferrin (CDT) levels in insurance applicants with elevated high density lipoprotein cholesterol (HDL) levels. Background .- Chronic alcoholism is not uncommon and is a risk factor for health and longevity and thus of interest to providers of insurance. A number of tests serve as markers of alcohol use, eg, blood alcohol level, elevated liver enzymes, ethyl glucuronide in urine, whole blood associated aldehyde (WBAA), macrocytosis, elevated HDL, elevated CDT and others. WBAA and CDT are usually only done, if some other screening test suggests alcohol use. HDL testing is routinely done for assessing cardiac risk, however, chronic alcohol intake tends to raise HDL and some insurance providers reflex to CDT testing when HDL is elevated. Methods .- A number of the clients of Heritage Labs Inc. have rules in place to test for CDT levels in specimens showing elevated HDL levels. The commonest HDL level that serves as the trigger for reflex testing for CDT is 80mg/dL. The results of this practice were analyzed to assess the utility of reflex testing for CDT to identify chronic alcohol abusers among the applicants. Results .- In examining the results of CDT levels done as a reflex test due to elevated HDL levels, about 2% of the applicants, 0.7% of women and 3% of men, tested positive for elevated CDT levels. Conclusions .- The incidence of elevated CDT levels is high enough to warrant routinely testing for this analyte in applicants, especially men, with high HDL levels. PMID:27584808

  5. Scavenger receptor-independent stimulation of cholesterol esterification in macrophages by low density lipoprotein extracted from human aortic intima.

    PubMed

    Steinbrecher, U P; Lougheed, M

    1992-05-01

    There is a growing body of evidence that suggests that modification of low density lipoprotein (LDL) in the artery wall may contribute to atherogenesis. A number of physiologically plausible modifications have been studied in vitro, including oxidation, aggregation, formation of complexes with glycosaminoglycans, and generation of LDL-immune complexes. Several studies of the properties of LDL extracted from the aortic intima have been published, but these indicate disagreement about both the nature and the extent of modification of LDL in the artery wall. The objectives of the present study were to determine the nature and extent of modification of LDL extracted from both normal and diseased human aortic intimas and to correlate this with the rate of LDL uptake in cultured cells. Analyses were performed on LDLs isolated from aortic intimas obtained at autopsy or at the time of organ harvest from 33 subjects. LDL from normal intima showed no clear evidence of oxidation but had slightly increased electrophoretic mobility compared with native plasma LDL, whereas LDL from plaques or fatty streaks exhibited variable but usually modest signs of oxidative change. Aortic LDL was more rapidly degraded by cultured macrophages than was plasma LDL and resulted in a greater stimulation of cholesterol esterification. The degree of stimulation of cholesterol esterification was correlated with the extent of modification of LDL as reflected by the degree of apolipoprotein B fragmentation. However, in all aortic LDLs the extent of oxidative change, as assessed by electrophoretic mobility or other physical parameters, was less than that required for scavenger receptor-mediated uptake. In all cases where sufficient amounts of LDL were recovered to permit degradation experiments, the uptake of aortic LDL was nonsaturable and could not be inhibited by polyinosinic acid or acetylated LDL. Chromatography on Sepharose CL-4B showed that most LDLs isolated from plaque contained a fraction

  6. Background diet and fat type alters plasma lipoprotein response but not aortic cholesterol accumulation in F1B Golden Syrian hamsters.

    PubMed

    Dillard, Alice; Matthan, Nirupa R; Spartano, Nicole L; Butkowski, Ann E; Lichtenstein, Alice H

    2013-12-01

    Dietary modification alters plasma lipoprotein profiles and atherosclerotic lesion progression in humans and some animal models. Variability in response to diet induced atherosclerosis has been reported in hamsters. Assessed was the interaction between background diet composition and dietary fat type on aortic cholesterol accumulation, lipoprotein profiles, hepatic lipids and selected genes. F1B Golden Syrian hamsters (20/group) were fed (12 weeks) semi-purified or non-purified diets containing either 10 % (w/w) coconut oil or safflower oil and 0.15 % (w/w) cholesterol. The non-purified diets relative to semi-purified diets resulted in significantly higher TC (72 % [percent difference] and 38 %, coconut oil and safflower oil, respectively) and nHDL-C (84 and 61 %, coconut oil and safflower oil, respectively), and lower HDL-C (-47 and -45 %, coconut oil and safflower oil, respectively) concentrations. Plasma triacylglycerol concentrations in the hamsters fed the non-purified coconut oil-supplemented diets were three- to fourfold higher than non-purified safflower oil-supplemented, and both semi-purified diets. With the exception of HDL-C, a significant effect of fat type was observed in TC, nHDL-C and triacylglycerol (all P < 0.05) concentrations. Regardless of diet induced differences in lipoprotein profiles, there was no significant effect on aortic cholesterol accumulation. There was an inverse relationship between plasma nHDL-C and triacylglycerol, and hepatic cholesteryl ester content (P < 0.001). Diet induced differences in hepatic gene transcription (LDL receptor, apoB-100, microsomal transfer protein) were not reflected in protein concentrations. Although hamsters fed non-purified and/or saturated fatty acid-supplemented diets had more atherogenic lipoprotein profiles compared to hamsters fed semi-purified and/or polyunsaturated fatty acid-supplemented diets these differences were not reflected in aortic cholesterol accumulation.

  7. Relation of Black Race between High Density Lipoprotein Cholesterol Content, High Density Lipoprotein Particles and Coronary Events (From the Dallas Heart Study)

    PubMed Central

    Chandra, Alvin; Neeland, Ian J.; Das, Sandeep R.; Khera, Amit; Turer, Aslan T.; Ayers, Colby R.; McGuire, Darren K.; Rohatgi, Anand

    2015-01-01

    Therapies targeting high density lipoprotein cholesterol content (HDL-C) have not improved coronary heart disease (CHD) outcomes. HDL particle concentration (HDL-P) may better predict CHD. However, the impact of race/ethnicity on the relations between HDL-P and subclinical atherosclerosis/ incident CHD events has not been described. Participants from the Dallas Heart Study, a multiethnic, probability-based, population cohort of Dallas County adults had the following baseline measurements: HDL-C, HDL-P by nuclear magnetic resonance imaging (NMR), and coronary artery calcium (CAC) by electron beam computed tomography. Participants were followed for a median of 9.3 years for incident CHD events (composite of first myocardial infarction, stroke, coronary revascularization, or cardiovascular death). The study comprised 1977 participants free from CHD (51% women, 46% Black). In adjusted models, HDL-C was not associated with prevalent CAC (p=0.13) or incident CHD overall (HR per 1SD: 0.89, 95% CI 0.76–1.05). However, HDL-C was inversely associated with incident CHD among non-Black (adjusted HR per 1SD 0.67, 95% CI 0.46–0.97) but not Black participants (HR 0.94, 95% CI 0.78–1.13, pinteraction = 0.05). Conversely, HDL-P, adjusted for risk factors and HDL-C, was inversely associated with prevalent CAC (p=0.009) and with incident CHD overall (adjusted HR per 1SD: 0.73, 95% CI 0.62–0.86) with no interaction by Black race/ethnicity (pinteraction = 0.57). In conclusion, in contrast to HDL-C, the inverse relationship between HDL-P and incident CHD events is consistent across ethnicities. These findings suggest that HDL-P is superior to HDL-C in predicting both prevalent atherosclerosis as well as incident CHD events across a diverse population and should be considered as a therapeutic target. PMID:25661572

  8. The Effects of Phellinus linteus Polysaccharide Extracts on Cholesterol Efflux in Oxidized Low-Density Lipoprotein-Loaded THP-1 Macrophages.

    PubMed

    Li, Xiao-hui; Li, Yan; Cheng, Zhao-yun; Cai, Xi-guo; Wang, Hong-min

    2015-06-01

    The removal of excess cellular cholesterol is critical for maintaining cellular cholesterol homeostasis. Phellinus linteus polysaccharide extracts (PLPEs) is an immunomudulatory agent with a molecular weight of 153 kd. Here, we analyzed the effects of PLPEs on cholesterol efflux in oxidized low-density lipoprotein (ox-LDL)-loaded THP-1 (human acute monocytic leukemia cell line) macrophages. Various concentrations of PLPEs (5, 10, 20, and 100 μg/mL) were used to treat cells. Cholesterol efflux analysis was performed to analyze the cholesterol efflux ratio in PLPE-treated cells. Semiquantitative reverse transcription-polymerase chain reaction and Western blot analysis were conducted to assess the expression of target genes. Low dose of PLPEs (5-20 μg/mL) dose dependently enhanced cholesterol efflux to apolipoprotein A-I (ApoA-I), evidenced by promoting the expression of adenosine 5'-triphosphate (ATP)-binding cassette A1, ATP-binding cassette G1, and peroxisome proliferation-activated receptor γ, key regulators for cholesterol efflux. Moreover, GW9662, a potent antagonist of peroxisome proliferation-activated receptor γ, inhibited PLPE (20 μg/mL)-promoted cholesterol efflux to ApoA-I in a dose-dependent fashion. However, high dose of PLPEs (100 μg/mL) inhibited cholesterol efflux to ApoA-I from ox-LDL-loaded THP-1 macrophages, enhanced the production of superoxide anion, decreased mitochondrial membrane potential and ATP levels, and raised nicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide phosphate oxidase subunits. Thus, these results indicate that low and high doses of PLPEs exhibit opposite effects on cholesterol efflux from ox-LDL-loaded THP-1 cells.

  9. Effect of a diet enriched with monounsaturated or polyunsaturated fatty acids on levels of low-density and high-density lipoprotein cholesterol in healthy women and men.

    PubMed

    Mensink, R P; Katan, M B

    1989-08-17

    Polyunsaturated fatty acids are thought to lower the serum cholesterol level more effectively than monounsaturated fatty acids. It is unclear whether the difference--if any--is due to a lowering of the level of high-density lipoprotein (HDL) or low-density lipoprotein (LDL) cholesterol. We therefore placed 31 women and 27 men on a mixed natural diet rich in saturated fat (19.3 percent of their daily energy intake from saturated fat, 11.5 percent from monounsaturated fat, and 4.6 percent from polyunsaturated fat) for 17 days. For the next 36 days, they received a mixed diet with the same total fat content, but enriched with olive oil and sunflower oil ("monounsaturated-fat diet": 12.9 percent saturated fat, 15.1 percent monounsaturated fat, and 7.9 percent polyunsaturated fat) or with sunflower oil alone ("polyunsaturated-fat diet": 12.6 percent saturated fat, 10.8 percent monounsaturated fat, and 12.7 percent polyunsaturated fat). The serum LDL cholesterol level decreased by 17.9 percent in those on the monounsaturated-fat diet and by 12.9 percent in those on the polyunsaturated-fat diet (95 percent confidence interval for the difference between the effects of the two unsaturated-fat diets, -9.9 percent to 0.0 percent). In men, the HDL cholesterol level fell slightly but not significantly with both diets. In women, the HDL cholesterol level did not change with either. We conclude that a mixed diet rich in monounsaturated fat was as effective as a diet rich in (n-6)polyunsaturated fat in lowering LDL cholesterol. Both diets lowered the level of HDL cholesterol slightly in men but not in women.

  10. Low Serum High Density Lipoprotein Cholesterol Concentration is an Independent Predictor for Enhanced Inflammation and Endothelial Activation

    PubMed Central

    Wan Ahmad, Wan Nor Hanis; Sakri, Farah; Mokhsin, Atiqah; Rahman, Thuhairah; Mohd Nasir, Nadzimah; Abdul-Razak, Suraya; Md Yasin, Mazapuspavina; Mohd Ismail, Aletza; Ismail, Zaliha; Nawawi, Hapizah

    2015-01-01

    Background Inflammation, endothelial activation and oxidative stress have been established as key events in the initiation and progression of atherosclerosis. High-density lipoprotein cholesterol (HDL-c) is protective against atherosclerosis and coronary heart disease, but its association with inflammation, endothelial activation and oxidative stress is not well established. Objectives (1) To compare the concentrations of biomarkers of inflammation, endothelial activation and oxidative stress in subjects with low HDL-c compared to normal HDL-c; (2) To examine the association and correlation between HDL-c and these biomarkers and (3) To determine whether HDL-c is an independent predictor of these biomarkers. Methods 422 subjects (mean age±SD = 43.2±11.9years) of whom 207 had low HDL-c concentrations (HDL-c <1.0mmol/L and <1.3mmol/L for males and females respectively) and 215 normal controls (HDL-c ≥1.0 and ≥1.3mmol/L for males and females respectively) were recruited in this study. The groups were matched for age, gender, ethnicity, smoking status, diabetes mellitus and hypertension. Fasting blood samples were collected for analysis of biomarkers of inflammation [high-sensitivity C-reactive protein (hsCRP) and Interleukin-6 (IL-6)], endothelial activation [soluble Vascular Cell Adhesion Molecule-1 (sVCAM-1), soluble Intercellular Adhesion Molecule-1 (sICAM-1) and E-selectin)] and oxidative stress [F2-Isoprostanes, oxidized Low Density Lipoprotein (ox-LDL) and Malondialdehyde (MDA)]. Results Subjects with low HDL-c had greater concentrations of inflammation, endothelial activation and oxidative stress biomarkers compared to controls. There were negative correlations between HDL-c concentration and biomarkers of inflammation (IL-6, p = 0.02), endothelial activation (sVCAM-1 and E-selectin, p = 0.029 and 0.002, respectively), and oxidative stress (MDA and F2-isoprostane, p = 0.036 and <0.0001, respectively). Multiple linear regression analysis showed HDL-c as an

  11. DPA n-3, DPA n-6 and DHA improve lipoprotein profiles and aortic function in hamsters fed a high cholesterol diet.

    PubMed

    Chen, Jingnan; Jiang, Yue; Liang, Yintong; Tian, Xiaoyu; Peng, Cheng; Ma, Ka Ying; Liu, Jian; Huang, Yu; Chen, Zhen-Yu

    2012-04-01

    The present study examined the cholesterol-lowering activity of omega-3 docosapentaenoic acid (DPA n-3), omega-6 docosapentaenoic acid (DPA n-6) and docosahexaenoic acid (DHA), and their interaction with gene expression of transporters, receptors and enzymes involved in cholesterol absorption and metabolism as well as their effect on aortic function. Forty hamsters were fed either the control diet containing 0.4% stearic acid or one of the three experimental diets containing 0.4% DPA n-3, 0.4% DPA n-6 and 0.4% DHA. Results showed that supplementation of these three fatty acids reduced plasma total cholesterol (TC) and non high-density-lipoprotein cholesterol (non-HDL-C) by 29-33% and 29-50%, respectively, compared with the control. The reduction in TC and non-HDL-C was accompanied by down-regulation of hepatic SREBP-2 and HMG-CoA reductase. Aorta from DPA n-3 and DHA groups was found to have significantly lesser tension and relax better than that from the control and DPA n-6 hamsters, largely mediated by their inhibition on the gene expression of cycloxygense-2 (COX-2). It was concluded that all three fatty acids were beneficial in improving lipoprotein profile with DPA n-3 and DHA having better effect on aortic function. PMID:22284366

  12. Impaired Cholesterol Efflux Capacity of High-Density Lipoprotein Isolated From Interstitial Fluid in Type 2 Diabetes Mellitus—Brief Report

    PubMed Central

    Tietge, Uwe J.F.; Dikkers, Arne; Parini, Paolo; Angelin, Bo; Rudling, Mats

    2016-01-01

    Objective— Patients with type 2 diabetes mellitus (T2D) have an increased risk of cardiovascular disease, the mechanism of which is incompletely understood. Their high-density lipoprotein (HDL) particles in plasma have been reported to have impaired cholesterol efflux capacity. However, the efflux capacity of HDL from interstitial fluid (IF), the starting point for reverse cholesterol transport, has not been studied. We here investigated the cholesterol efflux capacity of HDL from IF and plasma from T2D patients and healthy controls. Approach and Results— HDL was isolated from IF and peripheral plasma from 35 T2D patients and 35 age- and sex-matched healthy controls. Cholesterol efflux to HDL was determined in vitro, normalized for HDL cholesterol, using cholesterol-loaded macrophages. Efflux capacity of plasma HDL was 10% lower in T2D patients than in healthy controls, in line with previous observations. This difference was much more pronounced for HDL from IF, where efflux capacity was reduced by 28% in T2D. Somewhat surprisingly, the efflux capacity of HDL from IF was lower than that of plasma HDL, by 15% and 32% in controls and T2D patients, respectively. Conclusion— These data demonstrate that (1) HDL from IF has a lower cholesterol efflux capacity than plasma HDL and (2) the efflux capacity of HDL from IF is severely impaired in T2D when compared with controls. Because IF comprises the compartment where reverse cholesterol transport is initiated, the marked reduction in cholesterol efflux capacity of IF-HDL from T2D patients may play an important role for their increased risk to develop atherosclerosis. PMID:27034474

  13. Distinct Roles of Apolipoproteins A1 and E in the Modulation of High-Density Lipoprotein Composition and Function.

    PubMed

    Filou, Serafoula; Lhomme, Marie; Karavia, Eleni A; Kalogeropoulou, Christina; Theodoropoulos, Vassilis; Zvintzou, Evangelia; Sakellaropoulos, George C; Petropoulou, Peristera-Ioanna; Constantinou, Caterina; Kontush, Anatol; Kypreos, Kyriakos E

    2016-07-12

    In addition to high-density lipoprotein cholesterol (HDL-C) levels, HDL quality also appears to be very important for atheroprotection. Analysis of various clinical paradigms suggests that the lipid and apolipoprotein composition of HDL defines its size, shape, and functions and may determine its beneficial effects on human health. Previously, we reported that like apolipoprotein A-I (Apoa1), apolipoprotein E (Apoe) is also capable of promoting the de novo biogenesis of HDL with the participation of ATP binding cassette A lipid transporter member 1 (Abca1) and plasma enzyme lecithin:cholesterol acyltransferase (Lcat), in a manner independent of a functional Apoa1. Here, we performed a comparative analysis of the functions of these HDL subpopulations. Specifically, Apoe and Apoa1 double-deficient (Apoe(-/-) × Apoa1(-/-)) mice were infected with APOA1- or APOE3-expressing adenoviruses, and APOA1-containing HDL (APOA1-HDL) and APOE3-containing HDL (APOE3-HDL), respectively, were isolated and analyzed by biochemical and physicochemical methods. Western blot and lipidomic analyses indicated significant differences in the apolipoprotein and lipid composition of the two HDL species. Moreover APOE3-HDL presented a markedly reduced antioxidant potential and Abcg1-mediated cholesterol efflux capacity. Surprisingly, APOE3-HDL but not APOA1-HDL attenuated LPS-induced production of TNFα in RAW264.7 cells, suggesting that the anti-inflammatory effects of APOA1 are dependent on APOE expression. Taken together, our data indicate that APOA1 and APOE3 recruit different apolipoproteins and lipids on the HDL particle, leading to structurally and functionally distinct HDL subpopulations. The distinct role of these two apolipoproteins in the modulation of HDL functionality may pave the way toward the development of novel pharmaceuticals that aim to improve HDL functionality. PMID:27332083

  14. Pathways-Driven Sparse Regression Identifies Pathways and Genes Associated with High-Density Lipoprotein Cholesterol in Two Asian Cohorts

    PubMed Central

    Silver, Matt; Chen, Peng; Li, Ruoying; Cheng, Ching-Yu; Wong, Tien-Yin; Tai, E-Shyong; Teo, Yik-Ying; Montana, Giovanni

    2013-01-01

    Standard approaches to data analysis in genome-wide association studies (GWAS) ignore any potential functional relationships between gene variants. In contrast gene pathways analysis uses prior information on functional structure within the genome to identify pathways associated with a trait of interest. In a second step, important single nucleotide polymorphisms (SNPs) or genes may be identified within associated pathways. The pathways approach is motivated by the fact that genes do not act alone, but instead have effects that are likely to be mediated through their interaction in gene pathways. Where this is the case, pathways approaches may reveal aspects of a trait's genetic architecture that would otherwise be missed when considering SNPs in isolation. Most pathways methods begin by testing SNPs one at a time, and so fail to capitalise on the potential advantages inherent in a multi-SNP, joint modelling approach. Here, we describe a dual-level, sparse regression model for the simultaneous identification of pathways and genes associated with a quantitative trait. Our method takes account of various factors specific to the joint modelling of pathways with genome-wide data, including widespread correlation between genetic predictors, and the fact that variants may overlap multiple pathways. We use a resampling strategy that exploits finite sample variability to provide robust rankings for pathways and genes. We test our method through simulation, and use it to perform pathways-driven gene selection in a search for pathways and genes associated with variation in serum high-density lipoprotein cholesterol levels in two separate GWAS cohorts of Asian adults. By comparing results from both cohorts we identify a number of candidate pathways including those associated with cardiomyopathy, and T cell receptor and PPAR signalling. Highlighted genes include those associated with the L-type calcium channel, adenylate cyclase, integrin, laminin, MAPK signalling and immune

  15. High-density lipoprotein-cholesterol, daily estradiol and progesterone, and mammographic density phenotypes in premenopausal women.

    PubMed

    Flote, Vidar G; Frydenberg, Hanne; Ursin, Giske; Iversen, Anita; Fagerland, Morten W; Ellison, Peter T; Wist, Erik A; Egeland, Thore; Wilsgaard, Tom; McTiernan, Anne; Furberg, Anne-Sofie; Thune, Inger

    2015-06-01

    High-density lipoprotein-cholesterol (HDL-C) may influence the proliferation of breast tumor cells, but it is unclear whether low HDL-C levels, alone or in combination with cyclic estrogen and progesterone, are associated with mammographic density, a strong predictor of breast cancer development. Fasting morning serum concentrations of HDL-C were assessed in 202 premenopausal women, 25 to 35 years of age, participating in the Norwegian Energy Balance and Breast Cancer Aspects (EBBA) I study. Estrogen and progesterone were measured both in serum, and daily in saliva, throughout an entire menstrual cycle. Absolute and percent mammographic density was assessed by a computer-assisted method (Madena), from digitized mammograms (days 7-12). Multivariable models were used to study the associations between HDL-C, estrogen and progesterone, and mammographic density phenotypes. We observed a positive association between HDL-C and percent mammographic density after adjustments (P = 0.030). When combining HDL-C, estradiol, and progesterone, we observed among women with low HDL-C (<1.39 mmol/L), a linear association between salivary 17β-estradiol, progesterone, and percent and absolute mammographic density. Furthermore, in women with low HDL-C, each one SD increase of salivary mid-menstrual 17β-estradiol was associated with an OR of 4.12 (95% confidence intervals; CI, 1.30-13.0) of having above-median percent (28.5%), and an OR of 2.5 (95% CI, 1.13-5.50) of having above-median absolute mammographic density (32.4 cm(2)). On the basis of plausible biologic mechanisms linking HDL-C to breast cancer development, our findings suggest a role of HDL-C, alone or in combination with estrogen, in breast cancer development. However, our small hypothesis generating study requires confirmation in larger studies.

  16. Rapid Increase in Serum Low-Density Lipoprotein Cholesterol Concentration during Hepatitis C Interferon-Free Treatment

    PubMed Central

    Abiru, Seigo; Komori, Atsumasa; Nagaoka, Shinya; Saeki, Akira; Uchida, Shinjiro; Bekki, Shigemune; Kugiyama, Yuki; Nagata, Kazuyoshi; Nakamura, Minoru; Migita, Kiyoshi; Nakao, Kazuhiko

    2016-01-01

    Background & Aim We performed lipid analyses at the early period of therapy in patients with chronic hepatitis C who underwent interferon (IFN)-free direct-acting antiviral (DAA) treatment, and we attempted to identify the factors that contributed to a rapid increase in the patients’ serum low-density lipoprotein cholesterol (LDL-C) concentration. Methods We retrospectively analyzed the cases of 100 consecutive patients with HCV infection treated at the National Hospital Organization Nagasaki Medical Center: 24 patients underwent daclatasvir (DCV) and asunaprevir (ASV) combination therapy (DCV/ASV) for 24 weeks, and the other 76 patients underwent ledipasvir and sofosbuvir combination therapy (LDV/SOF) for 12 weeks. ΔLDL-C was defined as the changed in LDL-C level at 28 days from the start of therapy. To determine whether ΔLDL-C was associated with several kinds of factors including viral kinetics, we performed a stepwise multiple linear regression analysis. Results The LDL-C levels in patients treated with LDV/SOF were markedly and significantly elevated (87.45 to 122.5 mg/dl; p<10−10) compared to those in the DCV/ASV-treated patients (80.15 to 87.8 mg/dl; p = 0.0056). The median levels of ΔLDL-C in the LDV/SOF and DCV/ASV groups were 33.2 and 13.1, respectively. LDV/SOF combination therapy as an IFN-free regimen (p<0.001) and ΔHCV core antigen (0–1 day drop) (p<0.044) were identified as independent factors that were closely related to the ΔLDL-C. Conclusions A rapid increase in the serum LDL-C concentration during the IFN-free treatment of hepatitis C was associated with the type of HCV therapy and a decline of HCV core protein. PMID:27680885

  17. Low-Density Lipoprotein Cholesterol Levels and Statin Treatment by HIV Status Among Multicenter AIDS Cohort Study Men

    PubMed Central

    Fu, Wei; Zikusoka, Michelle N.; Jacobson, Lisa P.; Witt, Mallory D.; Palella, Frank J.; Kingsley, Lawrence A.; Post, Wendy S.; Brown, Todd T.

    2015-01-01

    Abstract Treating cardiovascular disease (CVD) risk factors, including dyslipidemia, is important in HIV care. Low-density lipoprotein cholesterol (LDL-c) target achievement is a readily available benchmark for dyslipidemia control, although use of this target is not uniformly endorsed by professional societies. We examined whether HIV serostatus is associated with not achieving LDL-c target. Among Multicenter AIDS Cohort Study (MACS) participants completing visit 56 (10/1/2011–3/31/2012), we categorized each man as on or off statin therapy and used NCEP ATP III guidelines to determine if each man was at LDL-c target or not at target. We compared proportions of men not at target and determined predictors using multivariate logistic regression. Sixty of 543 (11.1%) HIV-infected men and 87 of 585 (14.9%) HIV-uninfected men not receiving statin therapy were not at target (p=0.07), while 31 of 230 (13.5%) HIV-infected and 29 of 204 (14.2%) HIV-uninfected men receiving statin therapy were not at target (p=0.82). Factors associated with not being at target (among men not receiving statin therapy) included current smoking (OR=2.31, 95% CI 1.31, 4.06) and a diagnosis of hypertension (OR=4.69, 95% CI 2.68, 8.21). Factors associated with not being at target (among men receiving statin therapy) included current smoking (OR=2.72, 95% CI 1.30, 5.67) and diabetes (OR=5.31, 95% CI 2.47, 11.42). HIV-infected and HIV-uninfected men receiving statin therapy demonstrated similar nonachievement of LDL-c targets. Comorbidities (e.g., diabetes) lowered targets and may explain why goals were less likely to be met. PMID:25664922

  18. Triglycerides to High-Density Lipoprotein Cholesterol Ratio Can Predict Impaired Glucose Tolerance in Young Women with Polycystic Ovary Syndrome

    PubMed Central

    Song, Do Kyeong; Lee, Hyejin; Sung, Yeon-Ah

    2016-01-01

    Purpose The triglycerides to high-density lipoprotein cholesterol (TG/HDL-C) ratio could be related to insulin resistance (IR). We previously reported that Korean women with polycystic ovary syndrome (PCOS) had a high prevalence of impaired glucose tolerance (IGT). We aimed to determine the cutoff value of the TG/HDL-C ratio for predicting IR and to examine whether the TG/HDL-C ratio is useful for identifying individuals at risk of IGT in young Korean women with PCOS. Materials and Methods We recruited 450 women with PCOS (24±5 yrs) and performed a 75-g oral glucose tolerance test (OGTT). IR was assessed by a homeostasis model assessment index over that of the 95th percentile of regular-cycling women who served as the controls (n=450, 24±4 yrs). Results The cutoff value of the TG/HDL-C ratio for predicting IR was 2.5 in women with PCOS. Among the women with PCOS who had normal fasting glucose (NFG), the prevalence of IGT was significantly higher in the women with PCOS who had a high TG/HDL-C ratio compared with those with a low TG/HDL-C ratio (15.6% vs. 5.6%, p<0.05). Conclusion The cutoff value of the TG/HDL-C ratio for predicting IR was 2.5 in young Korean women with PCOS, and women with NFG and a high TG/HDL-C ratio had a higher prevalence of IGT. Therefore, Korean women with PCOS with a TG/HDL-C ratio >2.5 are recommended to be administered an OGTT to detect IGT even if they have NFG. PMID:27593868

  19. Genome-wide association studies identified novel loci for non-high-density lipoprotein cholesterol and its postprandial lipemic response

    PubMed Central

    An, Ping; Straka, Robert J.; Pollin, Toni I.; Feitosa, Mary F.; Wojczynski, Mary K.; Daw, E. Warwick; O'Connell, Jeffrey R.; Gibson, Quince; Ryan, Kathleen A.; Hopkins, Paul N.; Tsai, Michael Y.; Lai, Chao-Qiang; Province, Michael A.; Ordovas, Jose M.; Shuldiner, Alan R; Arnett, Donna K.; Borecki, Ingrid B.

    2014-01-01

    Non-high-density lipoprotein cholesterol (NHDL) is an independent and superior predictor of CVD risk as compared to LDL alone. It represents a spectrum of atherogenic lipid fractions with possibly a distinct genomic signature. We performed genome-wide association studies (GWAS) to identify loci influencing baseline NHDL and its postprandial lipemic (PPL) response. We carried out GWAS in 4,241 participants of European descent. Our discovery cohort included 928 subjects from the Genetics of Lipid-Lowering Drugs and Diet Network (GOLDN) Study. Our replication cohorts included 3,313 subjects from the Heredity and Phenotype Intervention (HAPI) Heart Study and Family Heart Study (FamHS). A linear mixed model using the kinship matrix was used for association tests. The best association signal was found in a tri-genic region at RHOQ-PIGF-CRIPT for baseline NHDL (lead SNP rs6544903, discovery p = 7e-7, MAF = 2%; validation p = 6e-4 at 0.1 kb upstream neighboring SNP rs3768725, and 5e-4 at 0.7 kb downstream neighboring SNP rs6733143, MAF = 10%). The lead and neighboring SNPs were not perfect surrogate proxies to each other (D′ = 1, r2 = 0.003) but they seemed to be partially dependent (likelihood ration test p = 0.04). Other suggestive loci (discovery p < 1e-6) included LOC100419812 and LOC100288337 for baseline NHDL, and LOC100420502 and CDH13 for NHDL PPL response that were not replicated (p > 0.01). The current and first GWAS of NHDL yielded an interesting common variant in RHOQ-PIGF-CRIPT influencing baseline NHDL levels. Another common variant in CDH13 for NHDL response to dietary high fat intake challenge was also suggested. Further validations for both loci from large independent studies, especially interventional studies, are warranted. PMID:24604477

  20. The CEPHEUS Pan-Asian survey: high low-density lipoprotein cholesterol goal attainment rate among hypercholesterolaemic patients undergoing lipid-lowering treatment in a Hong Kong regional centre.

    PubMed

    Chan, Raymond H W; Chan, P H; Chan, Kelvin K W; Lam, Simon C C; Hai, Jo Jo; Wong, Michael K L; Tam, Frankie C C; Lam, Linda; Chan, Carmen W S; Lam, Y M; Siu, David C W; Tse, H F; Lee, Stephen W L

    2012-10-01

    OBJECTIVES. To evaluate attainment of low-density lipoprotein cholesterol goals among hypercholesterolaemic patients undergoing lipid-lowering drug treatment in Hong Kong and to identify potential determinants of treatment outcomes. DESIGN. Cross-sectional observational study. SETTING. A single site in Hong Kong, as part of the CEPHEUS Pan-Asian survey. PATIENTS. Subjects with hypercholesterolaemia aged 18 years or above, who had been on lipid-lowering drug treatment for at least 3 months with no dose adjustment for at least 6 weeks. RESULTS. A total of 561 such patients (mean age, 65.3; standard deviation, 9.7 years) were evaluated. Most had major cardiovascular risk factors; 534 (95.2%) of 561 patients had coronary heart disease and 534 (95.4%) of 560 patients had low-density lipoprotein cholesterol goals set at lower than 70 mg/dL. In all, 465 (82.9%) patients attained their respective low-density lipoprotein cholesterol goals. Among 75 patients who had coronary heart disease or equivalent risk, and multiple risk factors with a 10-year coronary heart disease risk of over 20%, 62 (82.7%) attained their respective low-density lipoprotein cholesterol goals. Significant predictors of low-density lipoprotein cholesterol goal attainment included the patient's baseline lipid profile (total cholesterol and low-density lipoprotein cholesterol levels), blood pressure, and drugs (statin/non-statin) used for treatment. CONCLUSIONS. Hypercholesterolaemic patients undergoing lipid-lowering drug treatment in the present Hong Kong study were able to achieve a very high attainment rate for the low-density lipoprotein cholesterol goal, despite the fact that most of them had major cardiovascular risk factors.

  1. Lipoprotein Concentration, Particle Number, Size and Cholesterol Efflux Capacity are associated with Mitochondrial Oxidative Stress and Function in an HIV Positive Cohort

    PubMed Central

    Parikh, Nisha I; Gerschenson, Mariana; Bennett, Kara; Gangcuangco, Louie Mar M.; Lopez, Mary S.; Mehta, Nehal N.; Playford, Martin P.; Nakamoto, Beau K.; Seto, Todd B.; Chow, Dominic C.; Shikuma, Cecilia M.

    2015-01-01

    Background Association of lipoprotein particle size/number and HDL function with mitochondrial oxidative stress and function may underlie the excess cardiovascular (CVD) risk in HIV. Methods and Results Among HIV infected individuals on stable highly active antiretroviral therapy, we related standard and novel lipid measures [plasma total cholesterol, triglycerides, HDL-C, LDL-C, lipoprotein particle (-P) subclass size and number and HDL function (via cholesterol-efflux capacity)] with oxidative stress [peripheral blood mononuclear cell’s mitochondrial-specific 8-oxo-deoxyguanine (8-oxo-dG)] and function markers [oxidative phosphorylation (OXPHOS) NADH dehydrogenase (Complex I) and cytochrome c oxidase (Complex IV) enzyme activities]. Multivariable-adjusted logistic and linear regression analyses were employed adjusting for age, gender, CD4 nadir, viral load, smoking, diabetes, HOMA-IR, hypertension and lipid medications. Among 150 HIV-infected persons (mean age 52 years, 12% women, median CD4 count 524 cell/mm3), low HDL-C and high total cholesterol/HDL-C ratio were related to PBMC 8-oxo-deoxyguanine (p=0.01 and 0.02 respectively). Large HDL-P and HDL-P size were inversely related to PBMC 8-oxo-deoxyguanine (p=0.04). Small LDL-P (p=0.01) and total LDL-P (p=0.01) were related to decreased OXPHOS Complex I activity. LDL-P was related to decreased OXPHOS Complex IV activity (p=0.02). Cholesterol efflux capacity was associated with increased OXPHOS Complex IV activity. Conclusions HDL concentration and particle size and number are related to decreased PBMC mitochondrial oxidative stress whereas HDL function is positively related to mitochondrial oxidative function. The association we find between atherogenic lipoprotein profile and increased oxidative stress and function suggests these pathways may be important in the pathogenesis of cardiometabolic disease in HIV disease. PMID:25574857

  2. Correlation between high density lipoprotein-cholesterol and remodeling index in patients with coronary artery disease: IDEAS (IVUS diagnostic evaluation of atherosclerosis in Singapore)-HDL study.

    PubMed

    Lee, Chi-Hang; Tai, Bee-Choo; Lim, Gek-Hsiang; Chan, Mark Y; Low, Adrian F; Tan, Kathryn C; Chia, Boon-Lock; Tan, Huay-Cheem

    2012-01-01

    Serum level of high density lipoprotein (HDL)-cholesterol is associated with risk of coronary artery disease. We correlated the serum level of cholesterol with coronary artery remodeling index of patients with coronary artery disease. A total of 120 patients with de novo lesions located in native coronary artery were studied. Remodeling index was based on intravascular ultrasound (IVUS) interrogation of the lesions using the static approach, and was defined as external elastic membrane (EEM) area at lesion/average EEM area at proximal and distal reference segments. The average remodeling index was 0.9 (SD: 0.2). The remodeling index was not associated with any of the demographic and coronary risk factors. Stable angina was associated with a low remodeling index. Remodeling index correlated with white blood cell count and HDL-cholesterol, but not with total cholesterol, LDL-cholesterol and triglyceride. In the multiple linear regression analysis, HDL-cholesterol and procedure indication were the only 2 significant predictors of remodeling index. An increase of 1 mg/dL of HDL-cholesterol resulted in a decrease of 0.003 (95% CI: 0.0001, 0.007; P = 0.046) in remodeling index, after adjusting for procedural indications. When stratified according to diabetic status, the negative correlation persisted in non-diabetic (P = 0.023), but not in diabetic, patients (P = 0.707). We found a negative correlation between HDL-cholesterol level and remodeling index. Diabetic status may have an influence on the observed relationship. PMID:21197580

  3. High-density lipoproteins as modulators of endothelial cell functions: alterations in patients with coronary artery disease.

    PubMed

    Kratzer, Adelheid; Giral, Hector; Landmesser, Ulf

    2014-08-01

    Alteration of endothelial cell functions, including reduced endothelial nitric oxide (NO) availability, increased endothelial cell apoptosis, adhesion molecule/chemokine expression and pro-thrombotic activation are thought to contribute to the pathophysiology of atherosclerosis and coronary-artery-disease (CAD) with its clinical complications, such as acute coronary syndromes. High-density lipoproteins (HDL) from healthy subjects or reconstituted HDL have been observed to exert potential direct anti-atherogenic effects by modulating these endothelial cell functions. Importantly, endothelial effects of HDL have now been reported to be highly heterogeneous, and are modulated as part of immune responses. More recently, this has also been observed for HDL of patients with CAD, where HDL becomes potentially pro-inflammatory and endothelial-protective properties are markedly altered. Several mechanisms may lead to these altered endothelial effects of HDL in patients with CAD, including oxidative modification of HDL-associated lipids and proteins, such as apoA-I and paraoxonase-1, and alterations of HDL-proteome. These findings have to be considered with respect to interpretation of recent clinical studies failing to demonstrate reduced cardiovascular events by HDL-cholesterol raising strategies in patients with CAD. Both clinical and genetic studies suggest that HDL-cholesterol levels alone are not a sufficient therapeutic target in patients with CAD. The focus of this review is to summarize the role of HDL onto endothelial homeostasis and to describe recently characterized molecular pathways involved. We highlight how structural and functional modifications of HDL particles in patients with CAD may perturb the physiological homeostasis and lead to a loss of endothelial-protective properties of HDL in patients with CAD.

  4. Clinically used selective estrogen receptor modulators affect different steps of macrophage-specific reverse cholesterol transport

    PubMed Central

    Fernández-Suárez, María E.; Escolà-Gil, Joan C.; Pastor, Oscar; Dávalos, Alberto; Blanco-Vaca, Francisco; Lasunción, Miguel A.; Martínez-Botas, Javier; Gómez-Coronado, Diego

    2016-01-01

    Selective estrogen receptor modulators (SERMs) are widely prescribed drugs that alter cellular and whole-body cholesterol homeostasis. Here we evaluate the effect of SERMs on the macrophage-specific reverse cholesterol transport (M-RCT) pathway, which is mediated by HDL. Treatment of human and mouse macrophages with tamoxifen, raloxifene or toremifene induced the accumulation of cytoplasmic vesicles of acetyl-LDL-derived free cholesterol. The SERMs impaired cholesterol efflux to apolipoprotein A-I and HDL, and lowered ABCA1 and ABCG1 expression. These effects were not altered by the antiestrogen ICI 182,780 nor were they reproduced by 17β-estradiol. The treatment of mice with tamoxifen or raloxifene accelerated HDL-cholesteryl ester catabolism, thereby reducing HDL-cholesterol concentrations in serum. When [3H]cholesterol-loaded macrophages were injected into mice intraperitoneally, tamoxifen, but not raloxifene, decreased the [3H]cholesterol levels in serum, liver and feces. Both SERMs downregulated liver ABCG5 and ABCG8 protein expression, but tamoxifen reduced the capacity of HDL and plasma to promote macrophage cholesterol efflux to a greater extent than raloxifene. We conclude that SERMs interfere with intracellular cholesterol trafficking and efflux from macrophages. Tamoxifen, but not raloxifene, impair M-RCT in vivo. This effect is primarily attributable to the tamoxifen-mediated reduction of the capacity of HDL to promote cholesterol mobilization from macrophages. PMID:27601313

  5. Clinically used selective estrogen receptor modulators affect different steps of macrophage-specific reverse cholesterol transport.

    PubMed

    Fernández-Suárez, María E; Escolà-Gil, Joan C; Pastor, Oscar; Dávalos, Alberto; Blanco-Vaca, Francisco; Lasunción, Miguel A; Martínez-Botas, Javier; Gómez-Coronado, Diego

    2016-09-07

    Selective estrogen receptor modulators (SERMs) are widely prescribed drugs that alter cellular and whole-body cholesterol homeostasis. Here we evaluate the effect of SERMs on the macrophage-specific reverse cholesterol transport (M-RCT) pathway, which is mediated by HDL. Treatment of human and mouse macrophages with tamoxifen, raloxifene or toremifene induced the accumulation of cytoplasmic vesicles of acetyl-LDL-derived free cholesterol. The SERMs impaired cholesterol efflux to apolipoprotein A-I and HDL, and lowered ABCA1 and ABCG1 expression. These effects were not altered by the antiestrogen ICI 182,780 nor were they reproduced by 17β-estradiol. The treatment of mice with tamoxifen or raloxifene accelerated HDL-cholesteryl ester catabolism, thereby reducing HDL-cholesterol concentrations in serum. When [(3)H]cholesterol-loaded macrophages were injected into mice intraperitoneally, tamoxifen, but not raloxifene, decreased the [(3)H]cholesterol levels in serum, liver and feces. Both SERMs downregulated liver ABCG5 and ABCG8 protein expression, but tamoxifen reduced the capacity of HDL and plasma to promote macrophage cholesterol efflux to a greater extent than raloxifene. We conclude that SERMs interfere with intracellular cholesterol trafficking and efflux from macrophages. Tamoxifen, but not raloxifene, impair M-RCT in vivo. This effect is primarily attributable to the tamoxifen-mediated reduction of the capacity of HDL to promote cholesterol mobilization from macrophages.

  6. Clinically used selective estrogen receptor modulators affect different steps of macrophage-specific reverse cholesterol transport.

    PubMed

    Fernández-Suárez, María E; Escolà-Gil, Joan C; Pastor, Oscar; Dávalos, Alberto; Blanco-Vaca, Francisco; Lasunción, Miguel A; Martínez-Botas, Javier; Gómez-Coronado, Diego

    2016-01-01

    Selective estrogen receptor modulators (SERMs) are widely prescribed drugs that alter cellular and whole-body cholesterol homeostasis. Here we evaluate the effect of SERMs on the macrophage-specific reverse cholesterol transport (M-RCT) pathway, which is mediated by HDL. Treatment of human and mouse macrophages with tamoxifen, raloxifene or toremifene induced the accumulation of cytoplasmic vesicles of acetyl-LDL-derived free cholesterol. The SERMs impaired cholesterol efflux to apolipoprotein A-I and HDL, and lowered ABCA1 and ABCG1 expression. These effects were not altered by the antiestrogen ICI 182,780 nor were they reproduced by 17β-estradiol. The treatment of mice with tamoxifen or raloxifene accelerated HDL-cholesteryl ester catabolism, thereby reducing HDL-cholesterol concentrations in serum. When [(3)H]cholesterol-loaded macrophages were injected into mice intraperitoneally, tamoxifen, but not raloxifene, decreased the [(3)H]cholesterol levels in serum, liver and feces. Both SERMs downregulated liver ABCG5 and ABCG8 protein expression, but tamoxifen reduced the capacity of HDL and plasma to promote macrophage cholesterol efflux to a greater extent than raloxifene. We conclude that SERMs interfere with intracellular cholesterol trafficking and efflux from macrophages. Tamoxifen, but not raloxifene, impair M-RCT in vivo. This effect is primarily attributable to the tamoxifen-mediated reduction of the capacity of HDL to promote cholesterol mobilization from macrophages. PMID:27601313

  7. Effect of repeated apoA-IMilano/POPC infusion on lipids, (apo)lipoproteins, and serum cholesterol efflux capacity in cynomolgus monkeys.

    PubMed

    Kempen, Herman J; Gomaraschi, Monica; Bellibas, S Eralp; Plassmann, Stephanie; Zerler, Brad; Collins, Heidi L; Adelman, Steven J; Calabresi, Laura; Wijngaard, Peter L J

    2013-09-01

    MDCO-216, a complex of dimeric recombinant apoA-IMilano (apoA-IM) and palmitoyl-oleoyl-phosphatidylcholine (POPC), was administered to cynomolgus monkeys at 30, 100, and 300 mg/kg every other day for a total of 21 infusions, and effects on lipids, (apo)lipoproteins, and ex-vivo cholesterol efflux capacity were monitored. After 7 or 20 infusions, free cholesterol (FC) and phospholipids (PL) were strongly increased, and HDL-cholesterol (HDL-C), apoA-I, and apoA-II were strongly decreased. We then measured short-term effects on apoA-IM, lipids, and (apo)lipoproteins after the first or the last infusion. After the first infusion, PL and FC went up in the HDL region and also in the LDL and VLDL regions. ApoE shifted from HDL to LDL and VLDL regions, while ApoA-IM remained located in the HDL region. On day 41, ApoE levels were 8-fold higher than on day 1, and FC, PL, and apoE resided mostly in LDL and VLDL regions. Drug infusion quickly decreased the endogenous cholesterol esterification rate. ABCA1-mediated cholesterol efflux on day 41 was markedly increased, whereas scavenger receptor type B1 (SRB1) and ABCG1-mediated effluxes were only weakly increased. Strong increase of FC is due to sustained stimulation of ABCA1-mediated efflux, and drop in HDL and formation of large apoE-rich particles are due to lack of LCAT activation. PMID:23828780

  8. Effect of repeated apoA-IMilano/POPC infusion on lipids, (apo)lipoproteins, and serum cholesterol efflux capacity in cynomolgus monkeys[S

    PubMed Central

    Kempen, Herman J.; Gomaraschi, Monica; Bellibas, S. Eralp; Plassmann, Stephanie; Zerler, Brad; Collins, Heidi L.; Adelman, Steven J.; Calabresi, Laura; Wijngaard, Peter L. J.

    2013-01-01

    MDCO-216, a complex of dimeric recombinant apoA-IMilano (apoA-IM) and palmitoyl-oleoyl-phosphatidylcholine (POPC), was administered to cynomolgus monkeys at 30, 100, and 300 mg/kg every other day for a total of 21 infusions, and effects on lipids, (apo)lipoproteins, and ex-vivo cholesterol efflux capacity were monitored. After 7 or 20 infusions, free cholesterol (FC) and phospholipids (PL) were strongly increased, and HDL-cholesterol (HDL-C), apoA-I, and apoA-II were strongly decreased. We then measured short-term effects on apoA-IM, lipids, and (apo)lipoproteins after the first or the last infusion. After the first infusion, PL and FC went up in the HDL region and also in the LDL and VLDL regions. ApoE shifted from HDL to LDL and VLDL regions, while ApoA-IM remained located in the HDL region. On day 41, ApoE levels were 8-fold higher than on day 1, and FC, PL, and apoE resided mostly in LDL and VLDL regions. Drug infusion quickly decreased the endogenous cholesterol esterification rate. ABCA1-mediated cholesterol efflux on day 41 was markedly increased, whereas scavenger receptor type B1 (SRB1) and ABCG1-mediated effluxes were only weakly increased. Strong increase of FC is due to sustained stimulation of ABCA1-mediated efflux, and drop in HDL and formation of large apoE-rich particles are due to lack of LCAT activation. PMID:23828780

  9. [Effect of raw and cooked nopal (Opuntia ficus indica) ingestion on growth and profile of total cholesterol, lipoproteins, and blood glucose in rats].

    PubMed

    Cárdenas Medellín, M L; Serna Saldívar, S O; Velazco de la Garza, J

    1998-12-01

    Two different concentrations (approx. 6 and 12%) and two presentations (raw and cooked) of dehydrated nopal were fed to laboratory rats and growth and serum total cholesterol, lipoprotein profile and glucose determined. Samples of raw and cooked nopal were chemically characterized for moisture, protein, ash, crude fiber, ether extract, total dietary fiber, reducing sugars, amino acids, minerals and gross energy. Cooking slightly affected some of the nutrients analyzed. After one month feeding, blood was withdrawn via intracardiac puncture and serum glucose, total cholesterol, HDL, LDL, and VLDL were determined. Rats fed 12% nopal had lower weight gains (P < 0.05) when compared with counterparts fed 6% nopal or the control diet. Consumption of nopal did not affect (P > 0.05) glucose, total cholesterol and HDL cholesterol levels. However, rats fed raw nopal at the 12% concentration level had a 34% reduction in LDL cholesterol levels; thus, it was concluded that raw nopal had a potentially beneficial effect for hypercholesterolemic individuals. PMID:10347696

  10. High density- and beta-lipoprotein screening for risk of coronary artery disease in the context of new findings on reverse cholesterol transport.

    PubMed

    Levinson, Stanley S

    2002-01-01

    This article considers how high density lipoproteins (HDL) act as anti-arteriosclerotic agents, examines the usefulness of HDL indexes alone and in conjunction with other markers of coronary artery disease (CAD), and discusses how HDL markers compare with what one might expect from known metabolic mechanisms. This is accomplished by: (i) an overview of mechanisms associated with CAD, especially new findings regarding reverse cholesterol transport; (ii) a brief review of the clinical literature on biochemical markers for automated use; and (iii) analysis of data for persons with or without angiographically documented CAD. Based on these considerations, the ratio of optimized apo A-I/apo B appears superior to lipoprotein lipid markers for predicting the risk of CAD. Yet the ratio shows poor diagnostic accuracy by itself; it yields poorer diagnostic accuracy than would be expected from assessing the metabolic pathways. Discrimination is improved by using the ratio in conjunction with risk factors defined by the National Cholesterol Education Program (NCEP). Based on receiver-operator characteristic (ROC) curve data, this approach increases the accuracy by 13-14% above that obtained with current lipid markers; it improves discrimination more than the use of inflammatory markers. Apolipoprotein testing is better related to the mechanisms of cholesterol transport, is widely available, and requires only two tests, compared to three, to improve discrimination. However, inclusion of inflammatory markers may need to be considered in the future, when more information is available about their functions and clinical value. PMID:12017193

  11. Phenolic-extract from argan oil (Argania spinosa L.) inhibits human low-density lipoprotein (LDL) oxidation and enhances cholesterol efflux from human THP-1 macrophages.

    PubMed

    Berrougui, Hicham; Cloutier, Martin; Isabelle, Maxim; Khalil, Abdelouahed

    2006-02-01

    Argan oil is rich in unsaturated fatty acids, tocopherol and phenolic compounds. These protective molecules make further study of its cardiovascular diseases (CVDs) action interesting. Furthermore, no previous study has explored the antioxidant activity of argan oil in comparison with olive oil. The present study was conducted to evaluate the beneficial properties of Virgin argan oil phenolic extracts (VAO-PE) towards CVD by: (A) protecting human (low-density lipoprotein, LDL) against lipid peroxidation and (B) promoting high-density lipoprotein (HDL)-mediated cholesterol efflux. Human LDLs were oxidized by incubation with CuSO(4) in the presence of different concentrations of VAO-PE (0-320mug/ml). LDL lipid peroxidation was evaluated by conjugated diene and MDA formation as well as Vitamin E disappearance. Incubation of LDL with VAO-PE significantly prolonged the lag-phase and lowered the progression rate of lipid peroxidation (P<0.01) and reduced the disappearance of Vitamin E in a concentration-dependent manner. Incubation of HDL with VAO-PE significantly increased the fluidity of the HDL phospholipidic bilayer (P=0.0004) and HDL-mediated cholesterol efflux from THP-1 macrophages. These results suggest that Virgin argan oil provides a source of dietary phenolic antioxidants, which prevent cardiovascular diseases by inhibiting LDL-oxidation and enhancing reverse cholesterol transport. These properties increase the anti-atherogenic potential of HDL. PMID:16019008

  12. Phenolic-extract from argan oil (Argania spinosa L.) inhibits human low-density lipoprotein (LDL) oxidation and enhances cholesterol efflux from human THP-1 macrophages.

    PubMed

    Berrougui, Hicham; Cloutier, Martin; Isabelle, Maxim; Khalil, Abdelouahed

    2006-02-01

    Argan oil is rich in unsaturated fatty acids, tocopherol and phenolic compounds. These protective molecules make further study of its cardiovascular diseases (CVDs) action interesting. Furthermore, no previous study has explored the antioxidant activity of argan oil in comparison with olive oil. The present study was conducted to evaluate the beneficial properties of Virgin argan oil phenolic extracts (VAO-PE) towards CVD by: (A) protecting human (low-density lipoprotein, LDL) against lipid peroxidation and (B) promoting high-density lipoprotein (HDL)-mediated cholesterol efflux. Human LDLs were oxidized by incubation with CuSO(4) in the presence of different concentrations of VAO-PE (0-320mug/ml). LDL lipid peroxidation was evaluated by conjugated diene and MDA formation as well as Vitamin E disappearance. Incubation of LDL with VAO-PE significantly prolonged the lag-phase and lowered the progression rate of lipid peroxidation (P<0.01) and reduced the disappearance of Vitamin E in a concentration-dependent manner. Incubation of HDL with VAO-PE significantly increased the fluidity of the HDL phospholipidic bilayer (P=0.0004) and HDL-mediated cholesterol efflux from THP-1 macrophages. These results suggest that Virgin argan oil provides a source of dietary phenolic antioxidants, which prevent cardiovascular diseases by inhibiting LDL-oxidation and enhancing reverse cholesterol transport. These properties increase the anti-atherogenic potential of HDL.

  13. Home-Use Tests - Cholesterol

    MedlinePlus

    ... this test does: This is a home-use test kit to measure total cholesterol. What cholesterol is: Cholesterol is a fat (lipid) in your blood. High-density lipoprotein (HDL) ("good" cholesterol) helps protect your heart, but low-density lipoprotein (LDL) ("bad" cholesterol) can clog the arteries of your ...

  14. Statin therapy in patients with acute coronary syndrome: low-density lipoprotein cholesterol goal attainment and effect of statin potency

    PubMed Central

    Chinwong, Dujrudee; Patumanond, Jayanton; Chinwong, Surarong; Siriwattana, Khanchai; Gunaparn, Siriluck; Hall, John Joseph; Phrommintikul, Arintaya

    2015-01-01

    Background Elevated low-density lipoprotein cholesterol (LDL-C) is associated with an increased risk of coronary artery disease. Current guidelines recommend an LDL-C target of <70 mg/dL (<1.8 mmol/L) for acute coronary syndrome (ACS) patients, and the first-line treatment to lower lipids is statin therapy. Despite current guidelines and the efficacious lipid-lowering agents available, about half of patients at very high risk, including ACS patients, fail to achieve their LDL-C goal. This study assessed LDL-C goal attainment according to use of high and low potency statins in routine practice in Thailand. Methods A retrospective cohort study was performed by retrieving data from medical records and the electronic hospital database for a tertiary care hospital in Thailand between 2009 and 2011. Included were ACS patients treated with statins at baseline and with follow-up of LDL-C levels. Patients were divided into high or low potency statin users, and the proportion reaching the LDL-C goal of <70 mg/dL was determined. A Cox proportional hazard model was applied to determine the relationship between statin potency and LDL-C goal attainment. Propensity score adjustment was used to control for confounding by indication. Results Of 396 ACS patients (60% males, mean age 64.3±11.6 years), 229 (58%) were treated with high potency statins and 167 (42%) with low potency statins. A quarter reached their target LDL-C goal (25% for patients on high potency statins and 23% on low potency statins). High potency statins were not associated with increased LDL-C goal attainment (adjusted hazards ratio 1.22, 95% confidence interval 0.79–1.88; P=0.363). Conclusion There was no significant effect of high potency statins on LDL-C goal attainment. Moreover, this study showed low LDL-C goal attainment for patients on either low or high potency statins. The reasons for the low LDL-C goal attainment rate warrants further investigation. PMID:25670902

  15. Central Nervous System Lipoproteins

    PubMed Central

    Mahley, Robert W.

    2016-01-01

    ApoE on high-density lipoproteins is primarily responsible for lipid transport and cholesterol homeostasis in the central nervous system (CNS). Normally produced mostly by astrocytes, apoE is also produced under neuropathologic conditions by neurons. ApoE on high-density lipoproteins is critical in redistributing cholesterol and phospholipids for membrane repair and remodeling. The 3 main structural isoforms differ in their effectiveness. Unlike apoE2 and apoE3, apoE4 has markedly altered CNS metabolism, is associated with Alzheimer disease and other neurodegenerative disorders, and is expressed at lower levels in brain and cerebrospinal fluid. ApoE4-expressing cultured astrocytes and neurons have reduced cholesterol and phospholipid secretion, decreased lipid-binding capacity, and increased intracellular degradation. Two structural features are responsible for apoE4 dysfunction: domain interaction, in which arginine-61 interacts ionically with glutamic acid-255, and a less stable conformation than apoE3 and apoE2. Blocking domain interaction by gene targeting (replacing arginine-61 with threonine) or by small-molecule structure correctors increases CNS apoE4 levels and lipid-binding capacity and decreases intracellular degradation. Small molecules (drugs) that disrupt domain interaction, so-called structure correctors, could prevent the apoE4-associated neuropathology by blocking the formation of neurotoxic fragments. Understanding how to modulate CNS cholesterol transport and metabolism is providing important insights into CNS health and disease. PMID:27174096

  16. Robust passive and active efflux of cellular cholesterol to a designer functional mimic of high density lipoprotein

    PubMed Central

    Luthi, Andrea J.; Lyssenko, Nicholas N.; Quach, Duyen; McMahon, Kaylin M.; Millar, John S.; Vickers, Kasey C.; Rader, Daniel J.; Phillips, Michael C.; Mirkin, Chad A.; Thaxton, C. Shad

    2015-01-01

    The ability of HDL to support macrophage cholesterol efflux is an integral part of its atheroprotective action. Augmenting this ability, especially when HDL cholesterol efflux capacity from macrophages is poor, represents a promising therapeutic strategy. One approach to enhancing macrophage cholesterol efflux is infusing blood with HDL mimics. Previously, we reported the synthesis of a functional mimic of HDL (fmHDL) that consists of a gold nanoparticle template, a phospholipid bilayer, and apo A-I. In this work, we characterize the ability of fmHDL to support the well-established pathways of cellular cholesterol efflux from model cell lines and primary macrophages. fmHDL received cell cholesterol by unmediated (aqueous) and ABCG1- and scavenger receptor class B type I (SR-BI)-mediated diffusion. Furthermore, the fmHDL holoparticle accepted cholesterol and phospholipid by the ABCA1 pathway. These results demonstrate that fmHDL supports all the cholesterol efflux pathways available to native HDL and thus, represents a promising infusible therapeutic for enhancing macrophage cholesterol efflux. fmHDL accepts cholesterol from cells by all known pathways of cholesterol efflux: unmediated, ABCG1- and SR-BI-mediated diffusion, and through ABCA1. PMID:25652088

  17. Premature and severe cardiovascular disease in a Mexican male with markedly low high-density-lipoprotein-cholesterol levels and a mutation in the lecithin:cholesterol acyltransferase gene: a family study.

    PubMed

    Posadas-Sánchez, Rosalinda; Posadas-Romero, Carlos; Ocampo-Arcos, Wendy Angélica; Villarreal-Molina, María Teresa; Vargas-Alarcón, Gilberto; Antúnez-Argüelles, Erika; Mendoza-Pérez, Enrique; Cardoso-Saldaña, Guillermo; Martínez-Alvarado, Rocío; Medina-Urrutia, Aída; Jorge-Galarza, Esteban

    2014-06-01

    Epidemiological and clinical studies have shown that a low plasma high‑density lipoprotein cholesterol (HDL-C) level is a strong predictor of cardiovascular disease (CVD). Lecithin:cholesterol acyltransferase (LCAT) is a key enzyme in the formation, maturation and function of HDL. Therefore impaired LCAT function may enhance atherosclerosis because of defective cholesterol transport. In this study, we examined a 34-year old LCAT‑deficient patient and eight first-degree family members. There was a strong family history for CVD and type 2 diabetes mellitus (DM2). The proband was found homozygous for a previously reported LCAT gene mutation (Thr37Met). A sister and two sons of the proband were heterozygous for the same mutation. The proband had DM2 and showed severe multivessel coronary artery disease, corneal opacification and extremely low HDL-C levels. Large HDL particles were absent while small HDL particles were increased. The HDL of the patient had a reduced ability to promote cell cholesterol efflux, and the low‑density lipoproteins (LDL) were more susceptible to oxidation. Among his family members, two heterozygotes and one non-carrier had early carotid or coronary atherosclerosis. In conclusion, as the increased LDL oxidability and structural and functional abnormalities of HDL particles have been reported in patients with obesity and diabetes, the results suggested that the adverse coronary risk profile, and not being LCAT deficient, may be responsible for the CVD found in our proband, and for the early atherosclerosis observed in the two heterozygotes and in the wild‑type family members. PMID:24715031

  18. Association of Serum Cholesterol, Triglyceride, High and Low Density Lipoprotein (HDL and LDL) Levels in Chronic Periodontitis Subjects with Risk for Cardiovascular Disease (CVD): A Cross Sectional Study

    PubMed Central

    Sandi, R.M.; Pol, K.G.; Basavaraj, P.; Khuller, Nitin; Singh, Shilpi

    2014-01-01

    Purpose: To assess serum cholesterol, triglycerides, high and low density lipoprotein (HDL and LDL) levels (serum lipid profile) in subjects with chronic periodontitis and the possible association for risk of cardiovascular disease (CVD). Materials and Methods: Total of 80 participants (42 males and 38 females) who were in the age range of 30-65 years were divided into test group (group I- 40 subjects with chronic periodontitis) and control group (group II- 40 subjects with healthy periodontium), based on their periodontal disease statuses. Three ml of venous blood samples were taken for measurement of parameters of lipid metabolism [serum cholesterol (chol); triglycerides (Tg); HDL and LDL. Results: Significant increase in serum cholesterol and LDL (P<0.05) were observed in test group (group I), whereas serum triglycerides and HDL (P>0.66) showed no significant increase in test group (group I) as compared to their values in the control group (group II). A P-value of < 0.05 was considered for statistical significance. Conclusions: Subjects with chronic periodontitis showed increased serum cholesterol and LDL levels. This may suggest that these subjects are potentially at a risk of getting CVD. PMID:24596778

  19. Lack of an association or an inverse association between low-density-lipoprotein cholesterol and mortality in the elderly: a systematic review

    PubMed Central

    Ravnskov, Uffe; Diamond, David M; Hama, Rokura; Hamazaki, Tomohito; Hammarskjöld, Björn; Hynes, Niamh; Kendrick, Malcolm; Langsjoen, Peter H; Malhotra, Aseem; Mascitelli, Luca; McCully, Kilmer S; Ogushi, Yoichi; Okuyama, Harumi; Rosch, Paul J; Schersten, Tore; Sultan, Sherif; Sundberg, Ralf

    2016-01-01

    Objective It is well known that total cholesterol becomes less of a risk factor or not at all for all-cause and cardiovascular (CV) mortality with increasing age, but as little is known as to whether low-density lipoprotein cholesterol (LDL-C), one component of total cholesterol, is associated with mortality in the elderly, we decided to investigate this issue. Setting, participants and outcome measures We sought PubMed for cohort studies, where LDL-C had been investigated as a risk factor for all-cause and/or CV mortality in individuals ≥60 years from the general population. Results We identified 19 cohort studies including 30 cohorts with a total of 68 094 elderly people, where all-cause mortality was recorded in 28 cohorts and CV mortality in 9 cohorts. Inverse association between all-cause mortality and LDL-C was seen in 16 cohorts (in 14 with statistical significance) representing 92% of the number of participants, where this association was recorded. In the rest, no association was found. In two cohorts, CV mortality was highest in the lowest LDL-C quartile and with statistical significance; in seven cohorts, no association was found. Conclusions High LDL-C is inversely associated with mortality in most people over 60 years. This finding is inconsistent with the cholesterol hypothesis (ie, that cholesterol, particularly LDL-C, is inherently atherogenic). Since elderly people with high LDL-C live as long or longer than those with low LDL-C, our analysis provides reason to question the validity of the cholesterol hypothesis. Moreover, our study provides the rationale for a re-evaluation of guidelines recommending pharmacological reduction of LDL-C in the elderly as a component of cardiovascular disease prevention strategies. PMID:27292972

  20. A role for apolipoprotein E, apolipoprotein A-I, and low density lipoprotein receptors in cholesterol transport during regeneration and remyelination of the rat sciatic nerve.

    PubMed Central

    Boyles, J K; Zoellner, C D; Anderson, L J; Kosik, L M; Pitas, R E; Weisgraber, K H; Hui, D Y; Mahley, R W; Gebicke-Haerter, P J; Ignatius, M J

    1989-01-01

    Recent work has demonstrated that apo E secretion and accumulation increase in the regenerating peripheral nerve. The fact that apoE, in conjunction with apoA-I and LDL receptors, participates in a well-established lipid transfer system raised the possibility that apoE is also involved in lipid transport in the injured nerve. In the present study of the crushed rat sciatic nerve, a combination of techniques was used to trace the cellular associations of apoE, apoA-I, and the LDL receptor during nerve repair and to determine the distribution of lipid at each stage. After a crush injury, as axons died and Schwann cells reabsorbed myelin, resident and monocyte-derived macrophages produced large quantities of apoE distal to the injury site. As axons regenerated in the first week, their tips contained a high concentration of LDL receptors. After axon regeneration, apoE and apoA-I began to accumulate distal to the injury site and macrophages became increasingly cholesterol-loaded. As remyelination began in the second and third weeks after injury, Schwann cells exhausted their cholesterol stores, then displayed increased LDL receptors. Depletion of macrophage cholesterol stores followed over the next several weeks. During this stage of regeneration, apoE and apoA-I were present in the extracellular matrix as components of cholesterol-rich lipoproteins. Our results demonstrate that the regenerating peripheral nerve possesses the components of a cholesterol transfer mechanism, and the sequence of events suggests that this mechanism supplies the cholesterol required for rapid membrane biogenesis during axon regeneration and remyelination. Images PMID:2493483

  1. Effects of sphingomyelin degradation on cholesterol mobilization and efflux to high-density lipoproteins in cultured fibroblasts.

    PubMed

    Slotte, J P; Tenhunen, J; Pörn, I

    1990-06-27

    The hydrolysis of sphingomyelin from cellular plasma membranes imposes many consequences on cellular cholesterol homeostasis by causing a rapid and dramatic redistribution of plasma membrane cholesterol within the cells (Slotte, J.P. and Bierman, E.L. (1988) Biochem. J. 250, 653-658). The objective of this study was to examine the effects of an extracellular cholesterol acceptor on the directions of the sphingomyelinase-induced cholesterol flow in cultured fibroblasts. We have used HDL3 as a physiological acceptor for cholesterol, and measured the effects of sphingomyelin hydrolysis on efflux and endogenous esterification of cellular [3H]cholesterol. Treatment of cells with sphingomyelinase did induce a dramatically increased esterification of plasma-membrane-derived [3H]cholesterol. The presence of HDL3 in the medium (100 micrograms/ml) did not prevent or reduce the extent of the sphingomyelinase-induced cellular esterification of [3H]cholesterol. Degradation of cellular sphingomyelin (75% hydrolysis) also did not enhance the rate of [3H]cholesterol efflux from the plasma membranes to HDL3. In addition, we also observed that the degradation of sphingomyelin in the HDL3 particles (complete degradation) did not change the apparent rate of [3H]cholesterol transfer from HDL3 to the cells. These findings together indicate that hydrolysis of sphingomyelin did not markedly affect the rates of cholesterol surface transfer between HDL3 and cells. By whatever mechanism cholesterol is forced to be translocated from the plasma membranes subsequent to the degradation of sphingomyelin, it appears that the sterol flow is specifically directed towards the interior of the cells.

  2. The biology of PCSK9 from the endoplasmic reticulum to lysosomes: new and emerging therapeutics to control low-density lipoprotein cholesterol

    PubMed Central

    Poirier, Steve; Mayer, Gaétan

    2013-01-01

    Proprotein convertase subtilisin/kexin type 9 (PCSK9) directly binds to the epidermal growth factor-like repeat A domain of low-density lipoprotein receptor and induces its degradation, thereby controlling circulating low-density lipoprotein cholesterol (LDL-C) concentration. Heterozygous loss-of-function mutations in PCSK9 can decrease the incidence of coronary heart disease by up to 88%, owing to lifelong reduction of LDL-C. Moreover, two subjects with PCSK9 loss-of-function mutations on both alleles, resulting in a total absence of functional PCSK9, were found to have extremely low circulating LDL-C levels without other apparent abnormalities. Accordingly, PCSK9 could represent a safe and effective pharmacological target to increase clearance of LDL-C and to reduce the risk of coronary heart disease. Recent clinical trials using anti-PCSK9 monoclonal antibodies that block the PCSK9:low-density lipoprotein receptor interaction were shown to considerably reduce LDL-C levels by up to 65% when given alone and by up to 72% in patients already receiving statin therapy. In this review, we will discuss how major scientific breakthroughs in PCSK9 cell biology have led to the development of new and forthcoming LDL-C-lowering pharmacological agents. PMID:24115837

  3. Feedback modulation of cholesterol metabolism by the lipid-responsive non-coding RNA LeXis.

    PubMed

    Sallam, Tamer; Jones, Marius C; Gilliland, Thomas; Zhang, Li; Wu, Xiaohui; Eskin, Ascia; Sandhu, Jaspreet; Casero, David; Vallim, Thomas Q de Aguiar; Hong, Cynthia; Katz, Melanie; Lee, Richard; Whitelegge, Julian; Tontonoz, Peter

    2016-06-01

    Liver X receptors (LXRs) are transcriptional regulators of cellular and systemic cholesterol homeostasis. Under conditions of excess cholesterol, LXR activation induces the expression of several genes involved in cholesterol efflux, facilitates cholesterol esterification by promoting fatty acid synthesis, and inhibits cholesterol uptake by the low-density lipoprotein receptor. The fact that sterol content is maintained in a narrow range in most cell types and in the organism as a whole suggests that extensive crosstalk between regulatory pathways must exist. However, the molecular mechanisms that integrate LXRs with other lipid metabolic pathways are incompletely understood. Here we show that ligand activation of LXRs in mouse liver not only promotes cholesterol efflux, but also simultaneously inhibits cholesterol biosynthesis. We further identify the long non-coding RNA LeXis as a mediator of this effect. Hepatic LeXis expression is robustly induced in response to a Western diet (high in fat and cholesterol) or to pharmacological LXR activation. Raising or lowering LeXis levels in the liver affects the expression of genes involved in cholesterol biosynthesis and alters the cholesterol levels in the liver and plasma. LeXis interacts with and affects the DNA interactions of RALY, a heterogeneous ribonucleoprotein that acts as a transcriptional cofactor for cholesterol biosynthetic genes in the mouse liver. These findings outline a regulatory role for a non-coding RNA in lipid metabolism and advance our understanding of the mechanisms that coordinate sterol homeostasis.

  4. Feedback modulation of cholesterol metabolism by the lipid-responsive non-coding RNA LeXis.

    PubMed

    Sallam, Tamer; Jones, Marius C; Gilliland, Thomas; Zhang, Li; Wu, Xiaohui; Eskin, Ascia; Sandhu, Jaspreet; Casero, David; Vallim, Thomas Q de Aguiar; Hong, Cynthia; Katz, Melanie; Lee, Richard; Whitelegge, Julian; Tontonoz, Peter

    2016-06-01

    Liver X receptors (LXRs) are transcriptional regulators of cellular and systemic cholesterol homeostasis. Under conditions of excess cholesterol, LXR activation induces the expression of several genes involved in cholesterol efflux, facilitates cholesterol esterification by promoting fatty acid synthesis, and inhibits cholesterol uptake by the low-density lipoprotein receptor. The fact that sterol content is maintained in a narrow range in most cell types and in the organism as a whole suggests that extensive crosstalk between regulatory pathways must exist. However, the molecular mechanisms that integrate LXRs with other lipid metabolic pathways are incompletely understood. Here we show that ligand activation of LXRs in mouse liver not only promotes cholesterol efflux, but also simultaneously inhibits cholesterol biosynthesis. We further identify the long non-coding RNA LeXis as a mediator of this effect. Hepatic LeXis expression is robustly induced in response to a Western diet (high in fat and cholesterol) or to pharmacological LXR activation. Raising or lowering LeXis levels in the liver affects the expression of genes involved in cholesterol biosynthesis and alters the cholesterol levels in the liver and plasma. LeXis interacts with and affects the DNA interactions of RALY, a heterogeneous ribonucleoprotein that acts as a transcriptional cofactor for cholesterol biosynthetic genes in the mouse liver. These findings outline a regulatory role for a non-coding RNA in lipid metabolism and advance our understanding of the mechanisms that coordinate sterol homeostasis. PMID:27251289

  5. Comparison of Formulas for Calculating Low-density Lipoprotein Cholesterol in General Population and High-risk Patients with Cardiovascular Disease

    PubMed Central

    Choi, Hansol; Shim, Jee-Seon; Lee, Myung Ha; Yoon, Young Mi; Choi, Dong Phil

    2016-01-01

    Background and Objectives Low-density lipoprotein cholesterol (LDL-C), an established cardiovascular risk factor, can be generally determined by calculation from total cholesterol, high-density lipoprotein cholesterol, and triglyceride concentrations. The aim of this study was to compare LDL-C estimations using various formulas with directly measured LDL-C in a community-based group and hospital-based group among the Korean population. Subjects and Methods A total of 1498 participants were classified into four groups according to triglyceride concentrations as follows: <100, 100–199, 200–299, and ≥300 mg/dL. LDL-C was calculated using the Friedewald, Chen, Vujovic, Hattori, de Cordova, and Anandaraja formulas and directly measured using a homogenous enzymatic method. Pearson's correlation coefficients, intraclass correlation coefficients (ICC), Passing & Bablok regression, and Bland-Altman plots were used to evaluate the performance of six formulas. Results The Friedewald formula had the highest accuracy (ICC=0.977; 95% confidence interval 0.974-0.979) of all the triglyceride ranges, while the Vujovic formula had the highest accuracy (ICC=0.876; 98.75% confidence interval 0.668–0.951) in people with triglycerides ≥300 mg/dL. The mean difference was the lowest for the Friedewald formula (0.5 mg/dL) and the percentage error was the lowest for the Vujovic formula (30.2%). However, underestimation of the LDL-C formulas increased with triglyceride concentrations. Conclusion The accuracy of the LDL-C formulas varied considerably with differences in triglyceride concentrations. The Friedewald formula outperformed other formulas for estimating LDL-C against a direct measurement and the Vujovic formula was suitable for hypertriglyceridemic samples; it could be used as an alternative cost-effective tool to measure LDL-C when the direct measurement cannot be afforded.

  6. Prevalence of High Non-high-density Lipoprotein Cholesterol and Associated Risk Factors in Patients with Diabetes Mellitus in Jilin Province, China: A Cross-sectional Study.

    PubMed

    He, Huan; Zhen, Qing; Li, Yong; Kou, Chang Gui; Tao, Yu Chun; Wang, Chang; Kanu, Joseph Sam; Lu, Yu Ping; Yu, Ming Xi; Zhang, Hui Ping; Yu, Ya Qin; Li, Bo; Liu, Ya Wen

    2016-07-01

    Dyslipidemia is a risk factor for cardiovascular diseases (CVDs) in patients with diabetes, and non-high-density lipoprotein cholesterol (non-HDL-C) is a better predictor of CVDs than low-density lipoprotein cholesterol (LDL-C) in patients with diabetes. Therefore, we aimed to investigate the distribution of non-HDL-C and the prevalence of high non-HDL-C level in Chinese patients with diabetes mellitus and identify the associated risk factors. Non-HDL-C concentration positively correlated with total cholesterol, triglycerides, and LDL-C concentrations. Although both non-HDL-C and LDL-C concentration both related positively with TC concentration, the magnitude of correlation was relatively higher for non-HDL-C. The prevalence of high non-HDL-C (⋝4.14 mmol/L) was higher in two age groups (55-64 years: 46.7%; 65-79 years: 47.3%) than other age groups (18-24 years: 4.2%; 25-34 years: 43.6%; 35-44 years: 38.1%; 45-54 years: 41.0%). It was also higher among overweight (45.1%), generally obese (50.9%), or abdominally obese (47.3%) subjects, compared with normal weight subjects (34.5%). The risk of high non-HDL-C increased with advancing age. Both general obesity [odds ratio (OR)=1.488, 95% confidence interval (CI): 1.003-2.209] and abdominal obesity (OR=1.561, 95% CI: 1.101-2.214) were significantly associated with high non-HDL-C levels. PMID:27554125

  7. The Effect of Regular Aerobic Exercise on Reverse Cholesterol Transport A1 and Apo Lipoprotein A-I Gene Expression in Inactive Women

    PubMed Central

    Tofighi, Asghar; Rahmani, Fatemeh; Jamali Qarakhanlou, Bahram; Babaei, Solmaz

    2015-01-01

    Background: Atherosclerotic cardiovascular disease is currently a cause of mortality in some parts of the world. The ATP-Binding Cassette Transporter (ABCA1) gene prepares instructions to produce the ATP-binding cassette transporter protein whose operation is for export of phospholipids and cholesterol, outside cells where they are limited to Apolipoprotein A1 (apoA1). Increased ABCA1 activity could inhibit atherosclerosis. Objectives: In the present study, the effect of aerobic exercise was investigated on gene expression and biochemical parameters. Patients and Methods: The participants included 36 inactive women, which were randomly assigned to control (CON) and experimental (EX) groups. The EX group performed 12 weeks of aerobic exercise and the CON group remained inactive. Fasting blood samples were collected 24 hours before the first session and 48 hours after completion of the course. The ABCA1 and APOA1 gene expressions were measured using semi-quantitative-RT-PCR. Data were analyzed by the SPSS software (version 18). Results: A significant increase in blood ABCA1 (EX group P < 0.002, t = - 9.876) and Apo A-I (EX group P < 0.05, t = 2.76) gene expression was shown following the 12 weeks of training. Plasma high-density lipoprotein-cholesterol (HDL-C) concentration increased (P < 0.001, t = 4.90 respectively) while plasma low-density lipoprotein-cholesterol (LDL-C) concentration decreased (P < 0.001, t = 4.27) in the EX group compared with the CON group. Conclusions: Aerobic exercises can increase ABCA1 and APO-A1 gene expression. Induction of these genes can effectively prevent cardiovascular disease. PMID:26023346

  8. [Comparison of remnant lipoprotein-cholesterol measurements: the immune adsorption method (RLP-C) and the direct assay with detergent (RemL-C)].

    PubMed

    Hihara, Mari; Sato, Itsuko; Hayashi, Fujio; Sugiyama, Daisuke; Kawano, Seiji; Fujioka, Yoshio; Ishikawa, Yuichi; Kumagai, Shunichi

    2009-01-01

    Elevation of serum remnant lipoprotein concentration is an emerging risk factor for coronary artery disease. An immunoseparation procedure for remnant-like particle cholesterol(RLP-C) has been evaluated extensively in recent years. In addition, a new detergent-based method has been developed and applied to automated analyzer as "MetaboLead RemL-C" (RemL-C, KYOWA MEDEX CO., LTD.). Then, we compared the concentrations of remnant lipoproteins as RemL-C with those as RLP-C in various conditions. RemL-C assay was intra-assay-reproducible (n=20, CVs: 0.6-2.2%), and reproducible for 2 days in the refrigeration and for 8 hours in room temperature. This assay was also inter-assay-reproducible (during 5 days in the deep freezing, CVs: 1.6-3.0%). The available range for RemL-C assay was between 0.09 and 121.1 mg/dl. There were no detectable interferences from hemoglobin, free/conjugated bilirubin, chyle, and Intrafat. However, heparin influenced the titer of RemL-C concentrations. Correlation of values between RLP-C and RemL-C in 123 samples was excellent (r=0.924, p<0.001). However, different responses to intermediate lipoprotein fraction derived from a patients with type III hyperlipidemia were observed. In conclusion, RemL-C and RLP-C measurements may have a similar clinical significance. Differences in sensitivity for intermediate lipoprotein fraction between both methods may exist.

  9. Effect of serum lipoproteins and cholesterol on an exogenous pulmonary surfactant. ESR analysis of structural changes and their relation with surfactant activity.

    PubMed

    Martínez Sarrasague, María; Cimato, Alejandra; Piehl, Lidia; Brites, Fernando; Facorro, Graciela

    2013-12-01

    The study of structural changes in the surfactant may help to understand the mechanisms by which the surfactant is inactivated by serum. Here, we compared the in vitro effects of serum, albumin, lipoproteins (VLDL, LDL, HDL) and cholesterol on the dynamic and structural properties of surfactant suspensions by electronic spin resonance and surface tension measurements. Our results showed that albumin seems to be responsible for macrostructure disaggregation and increased rigidity in the hydrophobic region, but it did not affect surfactant activity. Fluidity in the polar area seems to be critical for proper physiological activity, and the changes induced by serum observed in this area would be generated by HDL or cholesterol, but the amount of cholesterol transferred by serum is not significant. Statistical analysis showed that surfactant activity correlated with the fluidity in the polar area but not with that in the hydrophobic region. We obtained strong evidence that among all the serum components tested, HDL is the one that causes the structural changes that compromise surfactant performance.

  10. Correlates of serum high-density lipoprotein cholesterol: a community-based study of middle-aged and older men and women in Japan.

    PubMed

    Chi, Dalei; Nakano, Masataka; Yamamoto, Koji

    2003-01-01

    The authors examined the relationships of high-density lipoprotein (HDL) cholesterol with sex, age, body composition, and lifestyle related factor including dietary patterns, alcohol consumption, smoking, and physical activity in a community-based sample from Mie prefecture, Japan. The study population comprised of 463 men (65.7+/-8.6 years) and 845 women (61.9+/-10.1 years) who participated in an annual healthy examination and a lifestyle related survey in 2001. Using factor analysis based on data from the lifestyle-related questionnaires, three dietary patterns were identified: prudent, Western, and high-salt dietary patterns. Univariate and multivariate analyses indicated that important predictors of higher HDL cholesterol levels were being female and a higher frequency of alcohol consumption. Less strongly related were age and a prudent dietary pattern. Smoking and body mass index (BMI) were strongly negatively related to HDL cholesterol levels. We suggested that efforts to reduce coronary heart disease risks focus on weight control and good daily lifestyles in middle-aged and older Japanese population.

  11. Implications of Total to High-Density Lipoprotein Cholesterol Ratio Discordance With Alternative Lipid Parameters for Coronary Atheroma Progression and Cardiovascular Events.

    PubMed

    Elshazly, Mohamed B; Nicholls, Stephen J; Nissen, Steven E; St John, Julie; Martin, Seth S; Jones, Steven R; Quispe, Renato; Stegman, Brian; Kapadia, Samir R; Tuzcu, E Murat; Puri, Rishi

    2016-09-01

    The total cholesterol to high-density lipoprotein cholesterol (TC/HDL-C) ratio may quantify atherogenic lipoproteins beyond low-density lipoprotein cholesterol (LDL-C), non-HDL-C and apolipoprotein B (apoB). We analyzed pooled data from 9 trials involving 4,957 patients with coronary artery disease undergoing serial intravascular ultrasonography to assess changes in percent atheroma volume (ΔPAV) and 2-year major adverse cardiovascular event (MACE) rates when TC/HDL-C levels were discordant with LDL-C, non-HDL-C, and apoB. Discordance was investigated when lipid levels were stratified by

  12. Cholesterol testing and results

    MedlinePlus

    ... VLDL cholesterol) Lipoproteins are made of fat and protein. They carry cholesterol, triglycerides, and other fats, called ... Pencina MJ, Navar-Boggan AM, D'Agostino RB Sr, Williams K, Neely B, Sniderman AD, Peterson ED. ...

  13. Resveratrol protects against diet-induced atherosclerosis by reducing low-density lipoprotein cholesterol and inhibiting inflammation in apolipoprotein E-deficient mice

    PubMed Central

    Chang, Geng-Ruei; Chen, Po-Lin; Hou, Po-Hsun; Mao, Frank Chiahung

    2015-01-01

    Objective(s): Resveratrol (RES) is a polyphenol compound that has been shown a promising cardioprotective effect. However, some reports have yielded conflicting findings. Herein, we investigated the anti-atherosclerotic effects of RES in apolipoprotein E (apo E)-deficient mice on a high cholesterol diet. Materials and Methods: Firstly, atherosclerosis was induced by feeding a high cholesterol diet to apo E-deficient mice. Then, we examined its effects on weight control, and serum interleukin-6 (IL-6) levels and used histopathological methods to analyze morphology and inflammatory marker of atherosclerotic lesions in mice orally supplemented with high (25 mg/kg/day) and low (5 mg/kg/day) doses of RES for 8 weeks. Results: Mice with high dose of RES had reduced epididymal fat pads, and lower serum IL-6 levels compared with those of control mice. Moreover, RES in high doses also decreased the low-density lipoprotein cholesterol (LDL-C) levels and atherogenic index (LDL-C/HDL-C) in the mice. Dissection of high-dose RES-treated mice revealed a marked reduction in fat deposition, percentage of mice with atherosclerotic lesion, and intima/media ratio in the aortic areas. The expressions of macrophage-specific marker F4/80 and cardiovascular inflammatory marker NF-κB in atherosclerotic vessels were both diminished in the atherosclerotic vessels of high-dose RES-supplementated apo E-deficient mice. Conclusion: These results suggest that RES prevented the effects of a high cholesterol diet on the rate of accretion in atherosclerosis progression by reducing the LDL-C levels and suppressing atherosclerotic inflammation. RES can therefore be valuable in the development of new anti-atherosclerotic agents. PMID:26949492

  14. Abnormal high density lipoproteins in cerebrotendinous xanthomatosis

    SciTech Connect

    Shore, V.; Salen, G.; Cheng, F.W.; Forte, T.; Shefer, S.; Tint, G.S.

    1981-11-01

    The plasma lipoprotein profiles and high density lipoproteins (HDL) were characterized in patients with the genetic disease cerebrotendinous xanthomatosis (CTX). The mean HDL-cholesterol concentration in the CTX plasmas was 14.5 +/- 3.2 mg/dl, about one-third the normal value. The low HDL-cholesterol reflects a low concentration and an abnormal lipid composition of the plasma HDL. Relative to normal HDL, the cholesteryl esters are low, free cholesterol and phospholipids essentially normal, and triglycerides increased. The ratio of apoprotein (apo) to total cholesterol in the HDL of CTX was two to three times greater than normal. In the CTX HDL, the ratio of apoAI to apoAII was high, the proportion of apoC low, and a normally minor form of apoAI increased relative to other forms. The HDL in electron micrographs appeared normal morphologically and in particle size. The adnormalities in lipoprotein distribution profiles and composition of the plasma HDL result from metabolic defects that are not understood but may be linked to the genetic defect in bile acid synthesis in CTX. As a consequence, it is probable that the normal functions of the HDL, possibly including modulation of LDL-cholesterol uptake and the removal of excess cholesterol from peripheral tissues, are perturbed significantly in this disease.

  15. The Effect of Residing Altitude on Levels of High-Density Lipoprotein Cholesterol: A Pilot Study From the Omani Arab Population.

    PubMed

    Al Riyami, Nafila B; Banerjee, Yajnavalka; Al-Waili, Khalid; Rizvi, Syed G; Al-Yahyaee, Said; Hassan, Mohammed O; Albarwani, Sulayma; Al-Rasadi, Khalid; Bayoumi, Riad A

    2015-07-01

    Lower mortality rates from coronary heart disease and higher levels of serum high-density lipoprotein cholesterol (HDL-C) have been observed in populations residing at high altitude. However, this effect has not been investigated in Arab populations, which exhibit considerable genetic homogeneity. We assessed the relationship between residing altitude and HDL-C in 2 genetically similar Omani Arab populations residing at different altitudes. The association between the levels of HDL-C and other metabolic parameters was also investigated. The levels of HDL-C were significantly higher in the high-altitude group compared with the low-altitude group. Stepwise regression analysis showed that altitude was the most significant factor affecting HDL-C, followed by gender, serum triglycerides, and finally the 2-hour postprandial plasma glucose. This finding is consistent with previously published studies from other populations and should be taken into consideration when comparing cardiovascular risk factors in populations residing at different altitudes.

  16. Two neglected biologic risk factors in bone grafting and implantology: high low-density lipoprotein cholesterol and low serum vitamin D.

    PubMed

    Choukroun, Joseph; Khoury, Georges; Khoury, Fouad; Russe, Philippe; Testori, Tiziano; Komiyama, Yataro; Sammartino, Gilberto; Palacci, Patrick; Tunali, Mustafa; Choukroun, Elisa

    2014-02-01

    Following a failure of a bone graft or an implant placement, the hypothesis of a biological abnormality is rarely considered as a possible cause. A systematic search of peer-reviewed literature for dyslipidemia or vitamin D deficiency may explain this lack of consideration. Excess low-density lipoprotein cholesterol (dyslipidemia) is responsible for a slower bone metabolism or lower dental implant osseointegration. In addition, vitamin D is a key factor for linking innate and adaptive immunity. Both of these factors are compromised under the conditions of vitamin D deficiency. Therefore, vitamin D deficiency slows implant osseointegration and increases the risk of graft infection. Vitamin D is also involved in immune function and therefore allergic reactions.

  17. Single particle tracking with sterol modulation reveals the cholesterol-mediated diffusion properties of integrin receptors

    NASA Astrophysics Data System (ADS)

    Arora, Neha; Syed, Aleem; Sander, Suzanne; Smith, Emily A.

    2014-12-01

    A combination of sterol modulation with cyclodextrins plus fluorescence microscopy revealed a biophysical mechanism behind cholesterol’s influence on the diffusion of a ubiquitous class of receptors called integrins. The heterogeneous diffusion of integrins bound to ligand-coated quantum dots was measured using single particle tracking (SPT), and the ensemble changes in integrin diffusion were measured by fluorescence recovery after photobleaching (FRAP). A 25 ± 1% reduction of membrane cholesterol resulted in three significant changes to the diffusion of ligand-bound αPS2CβPS integrins as measured by SPT. There was a 23% increase in ligand-bound mobile integrins; there was a statistically significant increase in the average diffusion coefficient inside zones of confined diffusion, and histograms of confined integrin trajectories showed an increased frequency in the range of 0.1-1 μm2 s-1 and a decreased frequency in the 0.001-0.1 μm2 s-1 range. No statistical change was measured in the duration of confinement nor the size of confined zones. Restoring the cholesterol-depleted cells with exogenous cholesterol or exogenous epicholesterol resulted in similar diffusion properties. Epicholesterol differs from cholesterol in the orientation of a single hydroxyl group. The ability of epicholesterol to substitute for cholesterol suggests a biophysical mechanism for cholesterol’s effect on integrin diffusion. Influences of bilayer thickness, viscosity and organization are discussed as possible explanations for the measured changes in integrin diffusion when the membrane cholesterol concentration is reduced.

  18. Modulation of Cholesterol-Related Gene Expression by Dietary Fiber Fractions from Edible Mushrooms.

    PubMed

    Caz, Víctor; Gil-Ramírez, Alicia; Largo, Carlota; Tabernero, María; Santamaría, Mónica; Martín-Hernández, Roberto; Marín, Francisco R; Reglero, Guillermo; Soler-Rivas, Cristina

    2015-08-26

    Mushrooms are a source of dietary fiber (DF) with a cholesterol-lowering effect. However, their underlying mechanisms are poorly understood. The effect of DF-enriched fractions from three mushrooms species on cholesterol-related expression was studied in vitro. The Pleurotus ostreatus DF fraction (PDF) was used in mice models to assess its potential palliative or preventive effect against hypercholesterolemia. PDF induced a transcriptional response in Caco-2 cells, suggesting a possible cholesterol-lowering effect. In the palliative setting, PDF reduced hepatic triglyceride likely because Dgat1 was downregulated. However, cholesterol-related biochemical data showed no changes and no relation with the observed transcriptional modulation. In the preventive setting, PDF modulated cholesterol-related genes expression in a manner similar to that of simvastatin and ezetimibe in the liver, although no changes in plasma and liver biochemical data were induced. Therefore, PDF may be useful reducing hepatic triglyceride accumulation. Because it induced a molecular response similar to hypocholesterolemic drugs in liver, further dose-dependent studies should be carried out. PMID:26284928

  19. Effects of a carbohydrate-restricted diet with and without supplemental soluble fiber on plasma low-density lipoprotein cholesterol and other clinical markers of cardiovascular risk.

    PubMed

    Wood, Richard J; Fernandez, Maria Luz; Sharman, Matthew J; Silvestre, Ricardo; Greene, Christine M; Zern, Tosca L; Shrestha, Sudeep; Judelson, Daniel A; Gomez, Ana L; Kraemer, William J; Volek, Jeff S

    2007-01-01

    Carbohydrate-restricted diets (CRDs) promote weight loss, reductions in plasma triacylglycerol (TAG) levels, and increases in high-density lipoprotein cholesterol (HDL-C) levels but may cause undesirable low-density lipoprotein cholesterol (LDL-C) responses in some people. The objective of the present study was to determine the effect of adding soluble fiber to a CRD on plasma LDL-C and other traditionally measured markers of cardiovascular disease. Using a parallel-arm, double-blind, placebo-controlled design, 30 overweight and obese men (body mass index, 25-35 kg/m(2)) were randomly assigned to supplement a CRD with soluble fiber (Konjac-mannan, 3g/d) (n = 15) or placebo (n = 15). Plasma lipids, anthropometrics, body composition, blood pressure, and nutrient intake were evaluated at baseline and at 6 and 12 weeks. Compliance was excellent as assessed by 7-day weighed dietary records and ketonuria. Both groups experienced decreases in (P < .01) body weight, percent body fat, systolic blood pressure, waist circumference, and plasma glucose levels. After 12 weeks, HDL-C and TAG improved significantly in the fiber (10% and -34%) and placebo (14%, -43%) groups. LDL-C decreased by 17.6% (P < .01) at week 6 and 14.1% (P < .01) at week 12 in the fiber group. Conversely, LDL-C reductions were significant in the placebo group only after 12 weeks (-6.0%, P < .05). We conclude that although clearly effective at lowering LDL-C, adding soluble fiber to a CRD during active and significant weight loss provides no additional benefits to the diet alone. Furthermore, a CRD led to clinically important positive alterations in cardiovascular disease risk factors.

  20. African Nutmeg (Monodora Myristica) Lowers Cholesterol and Modulates Lipid Peroxidation in Experimentally Induced Hypercholesterolemic Male Wistar Rats

    PubMed Central

    Onyenibe, Nwozo Sarah; Fowokemi, Kasumu Titilayo; Emmanuel, Oyinloye Babatunji

    2015-01-01

    To evaluate the cholesterol lowering potential and protective ability of aqueous extract of Monodora myristica experimental hypercholesterolemic rats, a short-term study was conducted. Hypercholesterolemia was induced by administering cholesterol orally at a dose of 40 mg/kg/0.3 ml. Plant extracts 100 or 200 mg/kg body weight and Questran 0.26 g/kg were administered five times a week for eight weeks for amelioration. Hypolipidemic effects were evaluated by measuring total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG) in the serum, while the protective ability was measured by the extent of lipid peroxidation (LPO) as well as enzymatic and non-enzymatic antioxidants levels in post mitochondrial fractions (PMF) of the hepatic and cardiac homogenates. Serum aminotransferases activities were also monitored. Results obtained shows that treatment with M. myristica elicited a significant reduction in serum TC, TG and LDL-C levels while there was concomitant increase in HDL-C of hypercholesterolemic rats. Elevations in serum aminotransferases activities and LPO level were reversed and a significant amelioration was noticed in enzymatic and non-enzymatic antioxidants status in the liver and heart of hypercholesterolemic rats. This study suggests that M. myristica possess cholesterol lowering potentials and protective ability in experimental hypercholesterolemia rat model. PMID:26199582

  1. African Nutmeg (Monodora Myristica) Lowers Cholesterol and Modulates Lipid Peroxidation in Experimentally Induced Hypercholesterolemic Male Wistar Rats.

    PubMed

    Onyenibe, Nwozo Sarah; Fowokemi, Kasumu Titilayo; Emmanuel, Oyinloye Babatunji

    2015-06-01

    To evaluate the cholesterol lowering potential and protective ability of aqueous extract of Monodora myristica experimental hypercholesterolemic rats, a short-term study was conducted. Hypercholesterolemia was induced by administering cholesterol orally at a dose of 40 mg/kg/0.3 ml. Plant extracts 100 or 200 mg/kg body weight and Questran 0.26 g/kg were administered five times a week for eight weeks for amelioration. Hypolipidemic effects were evaluated by measuring total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG) in the serum, while the protective ability was measured by the extent of lipid peroxidation (LPO) as well as enzymatic and non-enzymatic antioxidants levels in post mitochondrial fractions (PMF) of the hepatic and cardiac homogenates. Serum aminotransferases activities were also monitored. Results obtained shows that treatment with M. myristica elicited a significant reduction in serum TC, TG and LDL-C levels while there was concomitant increase in HDL-C of hypercholesterolemic rats. Elevations in serum aminotransferases activities and LPO level were reversed and a significant amelioration was noticed in enzymatic and non-enzymatic antioxidants status in the liver and heart of hypercholesterolemic rats. This study suggests that M. myristica possess cholesterol lowering potentials and protective ability in experimental hypercholesterolemia rat model. PMID:26199582

  2. Role of hepatic lipase and scavenger receptor BI in clearing phospholipid/free cholesterol-rich lipoproteins in PLTP-deficient mice.

    PubMed

    Kawano, Koichi; Qin, Shucun; Vieu, Claude; Collet, Xavier; Jiang, Xian-Cheng

    2002-07-11

    Phospholipid transfer protein knock-out (PLTP0) mice have defective transfer of phospholipids (PL) from triglyceride-rich lipoproteins (TRL) into high-density lipoproteins (HDL). In this study, we examined the role of diet, hepatic lipase (HL) and scavenger receptor BI (SRBI) in determining the accumulation of excess PL and free cholesterol (FC, "surface remnants") in plasma of PLTP0 mice. PL and FC accumulated in the very low-density lipoprotein (VLDL)-LDL region of PLTP0 mice on a highly saturated, coconut oil-based diet, but not on chow or milk-fat based Western diets. Accumulation of PL and FC was dramatically increased in PLTP0/HL0 mice, compared to PLTP0 mice, but only on the coconut oil diet. Turnover studies indicated that the coconut oil diet was associated with delayed catabolism of PL of PL/FC-rich particles. Incubation of these particles with primary hepatocytes in the presence of SRBI neutralizing antibody indicated that SRBI was primarily responsible for removal of FC and PL on the Western diet. In hepatocytes of coconut oil-fed mice, removal of FC and PL from these particles by SRBI was markedly reduced, even though SRBI protein expression levels were unchanged. These studies indicate that HL and SRBI both have major role in the clearance of PL and FC of surface remnants in PLTP0 mice. SRBI appears to be dysfunctional in coconut oil diet-fed animals, possibly related to changes in hepatocyte membrane fatty acid composition. PMID:12117557

  3. Dietary carbohydrate modifies the inverse association between saturated fat intake and cholesterol on very low-density lipoproteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We aimed to investigate the relationship between dietary saturated fat on fasting triglyceride (TG) and cholesterol levels, and any mediation of this relationship by dietary carbohydrate intake. Men and women in the NHLBI Genetics of Lipid-Lowering Drugs and Diet Network (GOLDN) study (n = 1036, mea...

  4. Lipolytic degradation of human very low density lipoproteins by human milk lipoprotein lipase: the identification of lipoprotein B as the main lipoprotein degradation product.

    PubMed

    Alaupovic, P; Wang, C S; McConathy, W J; Weiser, D; Downs, D

    1986-01-01

    /phospholipid-rich lipoproteins in the in vitro-formed LDL2 appears to be the main reason for their compositional difference from native LDL2. These results demonstrate that the formation of LP-B as the major apolipoprotein B-containing product of VLDL lipolysis only requires LPL as a catalyst and albumin as the fatty acid acceptor. However, under physiological circumstances, other modulating agents are necessary to prevent the accumulation and interaction of phospholipid/cholesterol-rich apolipoprotein C- and E-containing particles. PMID:3080947

  5. Gene-diet interactions with polymorphisms of the MGLL gene on plasma low-density lipoprotein cholesterol and size following an omega-3 polyunsaturated fatty acid supplementation: a clinical trial

    PubMed Central

    2014-01-01

    Background Omega-3 (n-3) polyunsaturated fatty acid (PUFA) consumption increases low-density lipoprotein (LDL) cholesterol (C) concentrations and particle size. Studies showed that individuals with large, buoyant LDL particles have decreased risk of cardiovascular diseases. However, a large inter-individual variability is observed in LDL particle size. Genetic factors may explain the variability of LDL-C concentrations and particle size after an n-3 PUFA supplementation. The monoglyceride lipase (MGLL) enzyme, encoded by the MGLL gene, plays an important role in lipid metabolism, especially lipoprotein metabolism. The aim of this study was to investigate if polymorphisms (SNPs) of the MGLL gene influence the variability of LDL-C and LDL particle size in response to an n-3 PUFA supplementation. Methods 210 subjects completed the study. They consumed 5 g/d of a fish oil supplement (1.9-2.2 g eicosapentaenoic acid and 1.1 g docosaexaenoic acid) during 6 weeks. Plasma lipids were measured before and after the supplementation period and 18 SNPs of the MGLL gene, covering 100% of common genetic variations (minor allele frequency ≥0.05), have been genotyped using TaqMan technology (Life Technologies Inc., Burlington, ON, CA). Results Following the n-3 PUFA supplementation, 55% of subjects increased their LDL-C levels. In a model including the supplementation, genotype and supplementation*genotype effects, gene-diet interaction effects on LDL-C concentrations (rs782440, rs6776142, rs555183, rs6780384, rs6787155 and rs1466571) and LDL particle size (rs9877819 and rs13076593) were observed for the MGLL gene SNPs (p < 0.05). Conclusion SNPs within the MGLL gene may modulate plasma LDL-C levels and particle size following an n-3 PUFA supplementation. This trial was registered at clinicaltrials.gov as NCT01343342. PMID:24884512

  6. Prevalence of the metabolic syndrome in patients with hypertension treated in general practice in Spain: an assessment of blood pressure and low-density lipoprotein cholesterol control and accuracy of diagnosis.

    PubMed

    Barrios, Vivencio; Escobar, Carlos; Calderón, Alberto; Llisterri, José L; Alegría, Eduardo; Muñiz, Javier; Matalí, Arantxa

    2007-01-01

    This study was designed to evaluate whether primary care physicians in Spain accurately diagnose the metabolic syndrome in hypertensive patients, to define the profile and management of these patients in clinical practice, and to ascertain the level of blood pressure and low-density lipoprotein cholesterol control. Data were analyzed from a cross-sectional survey involving 12,954 patients with hypertension (Prevención Cardiovascular en España en Atención Primaria: Intervención Sobre el Colesterol en Hipertensión [PRESCOT] study), wherein 52% of the cohort fulfilled the National Cholesterol Education Program-Adult Treatment Panel criteria for the metabolic syndrome. The majority of patients (54.6%) had 3 risk factors, 32.4% had 4, and 13% had 5 risk factors. Physician diagnosis of the metabolic syndrome was poor, with 43.7% of physicians missing the diagnosis and 12.9% wrongly diagnosing the metabolic syndrome. Blood pressure and low-density lipoprotein cholesterol control rates were very low, with only 4.7% of metabolic syndrome patients achieving control for both blood pressure and low-density lipoprotein cholesterol vs 13.5% for non-metabolic syndrome patients (P<.0001). These findings demonstrate that the metabolic syndrome is common in patients with hypertension and that it is generally poorly diagnosed and treated by primary care physicians. PMID:17684454

  7. Prevalence of the metabolic syndrome in patients with hypertension treated in general practice in Spain: an assessment of blood pressure and low-density lipoprotein cholesterol control and accuracy of diagnosis.

    PubMed

    Barrios, Vivencio; Escobar, Carlos; Calderón, Alberto; Llisterri, José L; Alegría, Eduardo; Muñiz, Javier; Matalí, Arantxa

    2007-01-01

    This study was designed to evaluate whether primary care physicians in Spain accurately diagnose the metabolic syndrome in hypertensive patients, to define the profile and management of these patients in clinical practice, and to ascertain the level of blood pressure and low-density lipoprotein cholesterol control. Data were analyzed from a cross-sectional survey involving 12,954 patients with hypertension (Prevención Cardiovascular en España en Atención Primaria: Intervención Sobre el Colesterol en Hipertensión [PRESCOT] study), wherein 52% of the cohort fulfilled the National Cholesterol Education Program-Adult Treatment Panel criteria for the metabolic syndrome. The majority of patients (54.6%) had 3 risk factors, 32.4% had 4, and 13% had 5 risk factors. Physician diagnosis of the metabolic syndrome was poor, with 43.7% of physicians missing the diagnosis and 12.9% wrongly diagnosing the metabolic syndrome. Blood pressure and low-density lipoprotein cholesterol control rates were very low, with only 4.7% of metabolic syndrome patients achieving control for both blood pressure and low-density lipoprotein cholesterol vs 13.5% for non-metabolic syndrome patients (P<.0001). These findings demonstrate that the metabolic syndrome is common in patients with hypertension and that it is generally poorly diagnosed and treated by primary care physicians.

  8. Patterns of association between genetic variability in apolipoprotein (apo) B, apo AI-CIII-AIV, and cholesterol ester transfer protein gene regions and quantitative variation in lipid and lipoprotein traits: influence of gender and exogenous hormones.

    PubMed Central

    Kessling, A; Ouellette, S; Bouffard, O; Chamberland, A; Bétard, C; Selinger, E; Xhignesse, M; Lussier-Cacan, S; Davignon, J

    1992-01-01

    Patterns of RFLP association were studied, to identify gene regions influencing quantitative variation in lipid and lipoprotein traits (coronary artery disease [CAD] risk factors or metabolically related traits). Subjects (118 female and 229 male; age 20-59 years) were selected for health. Multiple RFLPs were used to sample variability in regions around genes for apolipoprotein (apo) B (restriction enzymes HincII, PvuII, EcoRI, and XbaI), apo AI-CIII-AIV (BamHI, XmnI, TaqI, PstI, SstI, and PvuII) and cholesterol ester transfer protein (TaqI). Separate analyses were done by gender. The sample was truncated at mean +/- 4 SD, to remove extreme outliers. There was no significant gender difference in RFLP genotype frequency distribution. After trait-level adjustment to maximize removal of concomitant variability, analysis of variance was used to estimate the percentage trait phenotypic variance explained by measured variability in the gene regions studied. Fewer gene regions were involved in men, with less influence on quantitative trait variation than in women, in whom hormone use affected association patterns. Gender differences imply that pooling genders or adjusting data for gender effects removes genetic information and should be avoided. The association patterns show that variability around the candidate genes modulates trait levels: the genes are contributors to the genetics of CAD risk variables in a healthy sample. PMID:1346081

  9. Chlordecone, a mixed pregnane X receptor (PXR) and estrogen receptor alpha (ER{alpha}) agonist, alters cholesterol homeostasis and lipoprotein metabolism in C57BL/6 mice

    SciTech Connect

    Lee, Junga; Scheri, Richard C.; Zhang Yuan; Curtis, Lawrence R.

    2008-12-01

    Chlordecone (CD) is one of many banned organochlorine (OC) insecticides that are widespread persistent organic pollutants. OC insecticides alter lipid homeostasis in rodents at doses that are not neurotoxic or carcinogenic. Pretreatment of mice or rats with CD altered tissue distribution of a subsequent dose of [{sup 14}C]CD or [{sup 14}C]cholesterol (CH). Nuclear receptors regulate expression of genes important in the homeostasis of CH and other lipids. In this study, we report that CD suppresses in vitro reporter systems for human liver X receptors (LXRs) and activates those for human farnesoid X receptor (FXR), pregnane X receptor (PXR) and estrogen receptor {alpha} (ER{alpha}) in a concentration-dependent manner (0-50 {mu}M). Consistent with human PXR activation in vitro, three days after a single dose of CD (15 mg/kg) hepatic microsomal CYP3A11 protein increases in C57BL/6 mice. CD decreases hepatic CH ester content without altering total CH concentration. Apolipoprotein A-I (apoA-I) contents of hepatic lipoprotein-rich and microsomal fractions of CD-treated mice are higher than controls. There is a significant reduction in non-high density lipoprotein CH but not apolipoprotein B-48/100 (apoB-48/100) in plasma from CD-treated mice after a 4 h fast. At 14 days after 15 mg CD/kg apoA-I and apoB-100 proteins but not CYP3A11 protein in hepatic microsomes are similar to controls. This work indicates that altered CH homeostasis is a mode of OC insecticide action of relevance after a single dose. This at least partially explains altered CH tissue distribution in CD-pretreated mice.

  10. The association between high-density lipoprotein cholesterol level and cholesteryl ester transfer protein TaqIB gene polymorphism is influenced by alcohol drinking in a population-based sample.

    PubMed

    Tsujita, Yasuyuki; Nakamura, Yasuyuki; Zhang, Qishan; Tamaki, Shinji; Nozaki, Akihiko; Amamoto, Kenji; Kadowaki, Takashi; Kita, Yoshikuni; Okamura, Tomonori; Horie, Minoru; Ueshima, Hirotsugu

    2007-03-01

    Cholesteryl ester transfer protein (CETP) is a key enzyme in high-density lipoprotein (HDL) cholesterol metabolism. We studied the association between CETP TaqIB polymorphism and the HDL cholesterol levels considering environmental factors in a population-based sample consisting of 1729 participants who did not use lipid-lowering agents (659 men and 1070 women). The CETP TaqIB genotypes were determined by PCR-RFLP analysis. The serum HDL cholesterol levels of female participants with the B2B2 genotype were significantly higher than those with other genotypes (p<0.001). Multiple regression analysis with covariates such as age, waist to hip (W/H) ratio, alcohol drinking, current smoking, non-HDL cholesterol, and logarithm of triglyceride revealed that the CETP TaqIB genotype was an independent determinant of HDL cholesterol levels in men (p=0.049) and women (p<0.001). Subgroup analysis revealed that an interaction was observed between the CETP TaqIB polymorphism and alcohol consumption in the regulation of HDL cholesterol levels in men (p=0.049) and women (p=0.022). No interactions were observed between the CETP TaqIB polymorphism and current smoking status, body mass index, or W/H ratio in the regulation of HDL cholesterol levels. The association between the CETP TaqIB polymorphism and HDL cholesterol levels was more evident in alcohol consumers than in non-drinkers.

  11. Exercise raises high-density lipoprotein cholesterol in men after consumption of ground beef with a high but not low monounsaturated fatty acid-saturated fatty acid ratio.

    PubMed

    Crouse, Stephen F; Green, John S; Meade, Thomas H; Smith, Dana R; Smith, Stephen B

    2016-09-01

    Exercise and diets with higher monounsaturated fatty acid (MUFA):saturated fatty acid (SFA) ratios are independently linked to improved blood lipid profiles, yet interactive effects in men have not been studied. We hypothesized that dietary ground beef with a high MUFA:SFA ratio (HR = 1.1) would augment the beneficial changes in the lipid profile induced by exercise compared to dietary ground beef with a lower MUFA:SFA ratio (LR = 0.71). Untrained men (n = 13, age = 35 ± 12 y, weight = 91.4 ± 14.2 kg, body mass index = 27.8 ± 3.3kg/m(2)) consumed 5 HR or LR 114 g ground beef patties weekly for 5 weeks (random order) interspersed with a 4-week self-selected (SS) washout diet. One session of exercise (70% VO2max, 1675 kJ) was completed at the end of HR and LR diets, and again after a 5-week SS diet. Diets and physical activity were otherwise not controlled. Fasting blood samples for lipid and lipoprotein analyses were obtained 30 min before and 24 h after exercise. Subjects reported no other changes in diets or physical activity patterns, and body weight and body mass index did not change over the study duration. Diet (3) × Exercise Time (2) repeated measures analysis of variance (α = .05) and follow-up analyses revealed that blood concentrations (mmol/L ± SD) of total cholesterol (5.07 ± 1.16 to 5.73 ± 1.36), high-density lipoprotein cholesterol (HDL-C) (1.19 ± 0.20 to 1.36 ± 0.29), HDL2-C (0.24 ± 0.08 to 0.28 ± 0.11), HDL3-C (0.94 ± 0.14 to 1.08 ± 0.20), and non-HDL-C (3.88 ± 1.24 to 4.37 ± 1.38) were significantly elevated with exercise after the HR beef diet, but not after LR and SS diets. Thus, in healthy, untrained men the dietary beef MUFA:SFA ratio affects the blood lipid response to a single session of aerobic exercise. PMID:27632917

  12. Interactions between alcohol intake and the polymorphism of rs708272 on serum high-density lipoprotein cholesterol levels in the Guangxi Hei Yi Zhuang population.

    PubMed

    Zhou, Yijiang; Yin, Ruixing; Deng, Yaju; Li, Yiyang; Wu, Jinzhen

    2008-11-01

    Both alcohol consumption and the polymorphism of the cholesteryl ester transfer protein (CETP) TaqIB gene (rs708272) influence plasma high-density lipoprotein cholesterol (HDL-C) levels. However, their interactions on serum HDL-C levels is not well known. The present study was undertaken to detect the interactions between alcohol consumption and the rs708272 polymorphism on serum lipid levels in the Guangxi Hei Yi Zhuang population. Genotyping of the rs708272 in 342 nondrinkers and 416 drinkers aged 15-70 years was performed by polymerase chain reaction and restriction fragment length polymorphism. Interactions between rs708272 genotype and alcohol consumption was assessed using a cross-product term between genotypes and the aforementioned factor. Statistical significance was evaluated with analysis of co-variance. The frequency of B1 allele was 65.8% in nondrinkers and 64.7% in drinkers (P>.05), respectively. The frequencies of B1B1, B1B2, and B2B2 genotypes were 45.0%, 41.5%, and 13.5% in nondrinkers, and 41.3%, 46.6%, and 12.0% in drinkers (P>.05), respectively. The levels of HDL-C and apolipoprotein (Apo) AI in nondrinkers were higher in B2B2 genotype than in B1B1 genotype (P<.05 for each), whereas triglyceride (TG) levels in drinkers were higher in B1B1 genotype than in B1B2 genotype (P<.05). The levels of TG, HDL-C, Apo AI in B1B1 genotype, and HDL-C and Apo AI in B1B2 genotype were higher in drinkers than in nondrinkers (P<.05-.01), whereas the levels of low-density lipoprotein cholesterol (LDL-C) and Apo B in B2B2 genotype, and the levels of LDL-C in B1B1 genotype were lower in drinkers than in nondrinkers (P<.05-.01). The levels of HDL-C were positively correlated with female sex and genotype in nondrinkers (P<.001 for each), and were positively associated with age and alcohol consumption in drinkers (P<.005 and<.01, respectively). This study suggests that the B1 carriers benefited more from alcohol consumption than the B2 carriers in increasing serum HDL

  13. Potentiating the antitumour response of CD8(+) T cells by modulating cholesterol metabolism.

    PubMed

    Yang, Wei; Bai, Yibing; Xiong, Ying; Zhang, Jin; Chen, Shuokai; Zheng, Xiaojun; Meng, Xiangbo; Li, Lunyi; Wang, Jing; Xu, Chenguang; Yan, Chengsong; Wang, Lijuan; Chang, Catharine C Y; Chang, Ta-Yuan; Zhang, Ti; Zhou, Penghui; Song, Bao-Liang; Liu, Wanli; Sun, Shao-cong; Liu, Xiaolong; Li, Bo-liang; Xu, Chenqi

    2016-03-31

    CD8(+) T cells have a central role in antitumour immunity, but their activity is suppressed in the tumour microenvironment. Reactivating the cytotoxicity of CD8(+) T cells is of great clinical interest in cancer immunotherapy. Here we report a new mechanism by which the antitumour response of mouse CD8(+) T cells can be potentiated by modulating cholesterol metabolism. Inhibiting cholesterol esterification in T cells by genetic ablation or pharmacological inhibition of ACAT1, a key cholesterol esterification enzyme, led to potentiated effector function and enhanced proliferation of CD8(+) but not CD4(+) T cells. This is due to the increase in the plasma membrane cholesterol level of CD8(+) T cells, which causes enhanced T-cell receptor clustering and signalling as well as more efficient formation of the immunological synapse. ACAT1-deficient CD8(+) T cells were better than wild-type CD8(+) T cells at controlling melanoma growth and metastasis in mice. We used the ACAT inhibitor avasimibe, which was previously tested in clinical trials for treating atherosclerosis and showed a good human safety profile, to treat melanoma in mice and observed a good antitumour effect. A combined therapy of avasimibe plus an anti-PD-1 antibody showed better efficacy than monotherapies in controlling tumour progression. ACAT1, an established target for atherosclerosis, is therefore also a potential target for cancer immunotherapy. PMID:26982734

  14. Potentiating the antitumour response of CD8+ T cells by modulating cholesterol metabolism

    PubMed Central

    Yang, Wei; Bai, Yibing; Xiong, Ying; Zhang, Jin; Chen, Shuokai; Zheng, Xiaojun; Meng, Xiangbo; Li, Lunyi; Wang, Jing; Xu, Chenguang; Yan, Chengsong; Wang, Lijuan; Chang, Catharine C. Y.; Chang, Ta-Yuan; Zhang, Ti; Zhou, Penghui; Song, Bao-Liang; Liu, Wanli; Sun, Shao-cong; Liu, Xiaolong; Li, Bo-liang; Xu, Chenqi

    2016-01-01

    CD8+ T cells have a central role in antitumour immunity, but their activity is suppressed in the tumour microenvironment1–4. Reactivating the cytotoxicity of CD8+ T cells is of great clinical interest in cancer immunotherapy. Here we report a new mechanism by which the antitumour response of mouse CD8+ T cells can be potentiated by modulating cholesterol metabolism. Inhibiting cholesterol esterification in T cells by genetic ablation or pharmacological inhibition of ACAT1, a key cholesterol esterification enzyme5, led to potentiated effector function and enhanced proliferation of CD8+ but not CD4+ T cells. This is due to the increase in the plasma membrane cholesterol level of CD8+ T cells, which causes enhanced T-cell receptor clustering and signalling as well as more efficient formation of the immunological synapse. ACAT1-deficient CD8+ T cells were better than wild-type CD8+ T cells at controlling melanoma growth and metastasis in mice. We used the ACAT inhibitor avasimibe, which was previously tested in clinical trials for treating atherosclerosis and showed a good human safety profile6,7, to treat melanoma in mice and observed a good antitumour effect. A combined therapy of avasimibe plus an anti-PD-1 antibody showed better efficacy than monotherapies in controlling tumour progression. ACAT1, an established target for atherosclerosis, is therefore also a potential target for cancer immunotherapy. PMID:26982734

  15. Cilostazol reduces atherosclerosis by inhibition of superoxide and tumor necrosis factor-alpha formation in low-density lipoprotein receptor-null mice fed high cholesterol.

    PubMed

    Lee, Jeong Hyun; Oh, Goo Taeg; Park, So Youn; Choi, Jae-Hoon; Park, Jong-Gil; Kim, Chi Dae; Lee, Won Suk; Rhim, Byung Yong; Shin, Yung Woo; Hong, Ki Whan

    2005-05-01

    This study shows that 6-[4-(1-cyclohexyl-1H-tetrazol-5-yl) butoxy]-3,4-dihydro-2(1H)-quinolinone (cilostazol) suppresses the atherosclerotic lesion formation in the low-density lipoprotein receptor (Ldlr)-null mice. Ldlr-null mice fed a high cholesterol diet showed multiple plaque lesions in the proximal ascending aorta including aortic sinus, accompanied by increased macrophage accumulation with increased expression of vascular cell adhesion molecule-1 (VCAM-1) and monocyte chemoattractant protein-1 (MCP-1). Supplementation of cilostazol (0.2% w/w) in diet significantly decreased the plaque lesions with reduced macrophage accumulation and suppression of VCAM-1 and MCP-1 in situ. Increased superoxide and tumor necrosis factor-alpha (TNF-alpha) production were significantly lowered by cilostazol in situ as well as in cultured human umbilical vein endothelial cells (HUVECs). TNF-alpha-induced increased inhibitory kappaBalpha degradation in the cytoplasm and nuclear factor-kappaB (NF-kappaB) p65 activation in the nuclei of HUVECs were reversed by cilostazol (1 approximately 100 microM) as well as by (E)-3[(4-t-butylphenyl)sulfonyl]-2-propenenitrile (BAY 11-7085) (10 microM), suggesting that cilostazol strongly inhibits NF-kappaB activation and p65 translocation into the nuclei. Furthermore, in gel shift and DNA-binding assay, cilostazol inhibited NF-kappaB/DNA complex and nuclear DNA-binding activity of the NF-kappaB in the nuclear extracts of the RAW 264.7 cells. Taken together, it is suggested that the anti-atherogenic effect of cilostazol in cholesterol-fed Ldlr-null mice is ascribed to its property to suppress superoxide and TNF-alpha formation, and thereby reducing NF-kappaB activation/transcription, VCAM-1/MCP-1 expressions, and monocyte recruitments.

  16. Non-high-density lipoprotein cholesterol changes in middle-aged obese men with and without metabolic syndrome during weight loss.

    PubMed

    Kim, Maengkyu; Tanaka, Kiyoji

    2014-11-01

    Non-high-density lipoprotein (non-HDL-C) is the best predictor of coronary artery disease and stroke. Studies have shown that weight loss decreases non-HDL-C levels. However, whether diet-induced weight loss in individuals with and without metabolic syndrome causes a reduction in non-HDL-C levels remains unclear. We investigated the effects of weight loss on non-HDL-C levels in 34 middle-aged obese men with and without metabolic syndrome classified using National Cholesterol Education Panel Adult Treatment Panel III criteria (metabolic syndrome, n = 17; non-metabolic syndrome, n = 17). We conducted a 12-week dietary intervention using a low-carbohydrate, -fat, and -protein diet to reduce body weight. A significant decrease in body weight and body mass index in both groups was observed. However, the non-HDL-C level after weight loss was significantly decreased in the metabolic syndrome group (151.9 ± 6.8 to 131.4 ± 6.2 mg/dL, P < 0.01) but not in the non-metabolic syndrome group (152.1 ± 8.2 to 141.2 ± 8.1 mg/dL, P > 0.05). Levels of apolipoprotein AII and B, but not AI, were similarly decreased in both groups (P > 0.05). Pearson correlation analysis showed that the change in non-HDL-C levels in the metabolic syndrome group was strongly associated with levels of total cholesterol, fasting insulin, and alanine and aspartate transaminase, as well as homeostatic model assessment index, diastolic blood pressure, and maximal oxygen uptake (P < 0.05). These results demonstrated that diet-induced weight loss without physical activity decreases non-HDL-C levels, an important factor associated with changes in cardiorespiratory fitness and insulin sensitivity, in obese individuals with metabolic syndrome.

  17. Lipoprotein (a), lipids, and lipoproteins in patients with rheumatoid arthritis.

    PubMed Central

    Rantapää-Dahlqvist, S; Wållberg-Jonsson, S; Dahlén, G

    1991-01-01

    Lipoprotein (a), (Lp(a)), an independent atherogenic factor, was significantly increased in 93 patients with classical, seropositive rheumatoid arthritis of median disease activity. In the patients with Lp(a) concentrations above the upper reference value of 480 mg/l there was a significant correlation between Lp(a) and the concentration of orosomucoid, erythrocyte sedimentation rate, and the platelet count. The plasma concentrations of cholesterol and high density lipoprotein-cholesterol in both male and female patients were significantly lower than in controls. Apolipoprotein B and apolipoprotein AI in the patients correlated significantly with total cholesterol and high density lipoprotein-cholesterol respectively. PMID:1829348

  18. Role of low-density lipoprotein apheresis.

    PubMed

    Ziajka, Paul

    2005-08-22

    Low-density lipoprotein (LDL) apheresis has been shown to reduce plasma levels of total cholesterol, LDL cholesterol, and lipoprotein(a). In addition to these lipoprotein changes, LDL apheresis induces atherosclerosis regression, improves myocardial perfusion and endothelial function, and may reduce cardiovascular event rates. PMID:16098847

  19. Statin Discontinuation after Achieving a Target Low Density Lipoprotein Cholesterol Level in Type 2 Diabetic Patients without Cardiovascular Disease: A Randomized Controlled Study

    PubMed Central

    Lee, Seung-Hwan; Kwon, Hyuk-Sang; Park, Yong-Moon; Ko, Seung-Hyun; Choi, Yoon-Hee; Yoon, Kun-Ho

    2014-01-01

    Background This study investigated the rate of relapse of dyslipidemia and the factors which could predict relapse following a short-term statin discontinuation after achieving a target low density lipoprotein cholesterol (LDL-C) level in type 2 diabetic patients without cardiovascular disease (CVD). Methods Ninety-nine subjects on rosuvastatin treatment and whose LDL-C level was lower than 100 mg/dL were randomly assigned to discontinue or maintain statin treatment at a 2:1 ratio. The subjects were followed-up after 10 weeks. A relapse of dyslipidemia was defined as a reascent of LDL-C level to greater than 100 mg/dL. Results The statin discontinuation group had a significant rate of relapse compared to the maintenance group (79% vs. 3%, respectively). Pretreatment and baseline lipid levels, their ratios, and hemoglobin A1c level were significantly different between the relapse and nonrelapse groups. The pretreatment and baseline lipid profiles and their ratios were independently associated with relapse. The pretreatment LDL-C level was the most useful parameter for predicting a relapse, with a cutoff of 123 mg/dL. During the follow-up period, no CVD event was noted. Conclusion The relapse rate of dyslipidemia was high when statins were discontinued in type 2 diabetic patients without CVD. Statin discontinuation should be considered carefully based on the pretreatment lipid profiles of patients. PMID:24627830

  20. Impact of Statins Therapy for Ischemic Heart Disease Patients with Low-Density Lipoprotein Cholesterol Levels Less Than 100 mg/dL

    PubMed Central

    Kuwabara, Masanori; Kondo, Fumiaki; Hamada, Tomoyuki; Takahashi, Jun-ichi; Takenaka, Nanae; Furuno, Takashi

    2016-01-01

    Background The objective of this study was to determine whether the use of statins prevents the progression of ischemic heart disease (IHD) in patients with low levels of low-density lipoprotein cholesterol (LDL-C). Methods We reviewed data obtained from IHD patients who underwent first percutaneous coronary intervention (PCI). Patients underwent follow-up coronary angiography (re-CAG) after PCI. However, only patients with LDL-C levels less than 100 mg/dL at PCI were included in this study. Ultimately, 92 patients were enrolled. All patients were divided into two groups: 1) patients who were treated with statins (n = 69), and 2) patients who were not treated with statins (n = 23). Results The two groups had similar LDL-C levels at PCI. At re-CAG, the ratio of patients who underwent PCI for de novo lesion in the statin group was lower than that in the non-statin group (12% vs. 48%) (p < 0.001). In multiple regression analysis, statin usage and LDL-C level at PCI were independent predictors of the ratio of patients undergoing PCI for de novo lesion. Conclusions Statins therapy for patients whose LDL-C levels are less than 100 mg/dL has a beneficial effect on secondary prevention of IHD. PMID:27713605

  1. Oxidized Low-density Lipoprotein (ox-LDL) Cholesterol Induces the Expression of miRNA-223 and L-type Calcium Channel Protein in Atrial Fibrillation

    NASA Astrophysics Data System (ADS)

    He, Fengping; Xu, Xin; Yuan, Shuguo; Tan, Liangqiu; Gao, Lingjun; Ma, Shaochun; Zhang, Shebin; Ma, Zhanzhong; Jiang, Wei; Liu, Fenglian; Chen, Baofeng; Zhang, Beibei; Pang, Jungang; Huang, Xiuyan; Weng, Jiaqiang

    2016-08-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia causing high morbidity and mortality. While changing of the cellular calcium homeostasis plays a critical role in AF, the L-type calcium channel α1c protein has suggested as an important regulator of reentrant spiral dynamics and is a major component of AF-related electrical remodeling. Our computational modeling predicted that miRNA-223 may regulate the CACNA1C gene which encodes the cardiac L-type calcium channel α1c subunit. We found that oxidized low-density lipoprotein (ox-LDL) cholesterol significantly up-regulates both the expression of miRNA-223 and L-type calcium channel protein. In contrast, knockdown of miRNA-223 reduced L-type calcium channel protein expression, while genetic knockdown of endogenous miRNA-223 dampened AF vulnerability. Transfection of miRNA-223 by adenovirus-mediated expression enhanced L-type calcium currents and promoted AF in mice while co-injection of a CACNA1C-specific miR-mimic counteracted the effect. Taken together, ox-LDL, as a known factor in AF-associated remodeling, positively regulates miRNA-223 transcription and L-type calcium channel protein expression. Our results implicate a new molecular mechanism for AF in which miRNA-223 can be used as an biomarker of AF rheumatic heart disease.

  2. Oxidized Low-density Lipoprotein (ox-LDL) Cholesterol Induces the Expression of miRNA-223 and L-type Calcium Channel Protein in Atrial Fibrillation.

    PubMed

    He, Fengping; Xu, Xin; Yuan, Shuguo; Tan, Liangqiu; Gao, Lingjun; Ma, Shaochun; Zhang, Shebin; Ma, Zhanzhong; Jiang, Wei; Liu, Fenglian; Chen, Baofeng; Zhang, Beibei; Pang, Jungang; Huang, Xiuyan; Weng, Jiaqiang

    2016-01-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia causing high morbidity and mortality. While changing of the cellular calcium homeostasis plays a critical role in AF, the L-type calcium channel α1c protein has suggested as an important regulator of reentrant spiral dynamics and is a major component of AF-related electrical remodeling. Our computational modeling predicted that miRNA-223 may regulate the CACNA1C gene which encodes the cardiac L-type calcium channel α1c subunit. We found that oxidized low-density lipoprotein (ox-LDL) cholesterol significantly up-regulates both the expression of miRNA-223 and L-type calcium channel protein. In contrast, knockdown of miRNA-223 reduced L-type calcium channel protein expression, while genetic knockdown of endogenous miRNA-223 dampened AF vulnerability. Transfection of miRNA-223 by adenovirus-mediated expression enhanced L-type calcium currents and promoted AF in mice while co-injection of a CACNA1C-specific miR-mimic counteracted the effect. Taken together, ox-LDL, as a known factor in AF-associated remodeling, positively regulates miRNA-223 transcription and L-type calcium channel protein expression. Our results implicate a new molecular mechanism for AF in which miRNA-223 can be used as an biomarker of AF rheumatic heart disease. PMID:27488468

  3. Oxidized Low-density Lipoprotein (ox-LDL) Cholesterol Induces the Expression of miRNA-223 and L-type Calcium Channel Protein in Atrial Fibrillation.

    PubMed

    He, Fengping; Xu, Xin; Yuan, Shuguo; Tan, Liangqiu; Gao, Lingjun; Ma, Shaochun; Zhang, Shebin; Ma, Zhanzhong; Jiang, Wei; Liu, Fenglian; Chen, Baofeng; Zhang, Beibei; Pang, Jungang; Huang, Xiuyan; Weng, Jiaqiang

    2016-08-04

    Atrial fibrillation (AF) is the most common sustained arrhythmia causing high morbidity and mortality. While changing of the cellular calcium homeostasis plays a critical role in AF, the L-type calcium channel α1c protein has suggested as an important regulator of reentrant spiral dynamics and is a major component of AF-related electrical remodeling. Our computational modeling predicted that miRNA-223 may regulate the CACNA1C gene which encodes the cardiac L-type calcium channel α1c subunit. We found that oxidized low-density lipoprotein (ox-LDL) cholesterol significantly up-regulates both the expression of miRNA-223 and L-type calcium channel protein. In contrast, knockdown of miRNA-223 reduced L-type calcium channel protein expression, while genetic knockdown of endogenous miRNA-223 dampened AF vulnerability. Transfection of miRNA-223 by adenovirus-mediated expression enhanced L-type calcium currents and promoted AF in mice while co-injection of a CACNA1C-specific miR-mimic counteracted the effect. Taken together, ox-LDL, as a known factor in AF-associated remodeling, positively regulates miRNA-223 transcription and L-type calcium channel protein expression. Our results implicate a new molecular mechanism for AF in which miRNA-223 can be used as an biomarker of AF rheumatic heart disease.

  4. Oxidized Low-density Lipoprotein (ox-LDL) Cholesterol Induces the Expression of miRNA-223 and L-type Calcium Channel Protein in Atrial Fibrillation

    PubMed Central

    He, Fengping; Xu, Xin; Yuan, Shuguo; Tan, Liangqiu; Gao, Lingjun; Ma, Shaochun; Zhang, Shebin; Ma, Zhanzhong; Jiang, Wei; Liu, Fenglian; Chen, Baofeng; Zhang, Beibei; Pang, Jungang; Huang, Xiuyan; Weng, Jiaqiang

    2016-01-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia causing high morbidity and mortality. While changing of the cellular calcium homeostasis plays a critical role in AF, the L-type calcium channel α1c protein has suggested as an important regulator of reentrant spiral dynamics and is a major component of AF-related electrical remodeling. Our computational modeling predicted that miRNA-223 may regulate the CACNA1C gene which encodes the cardiac L-type calcium channel α1c subunit. We found that oxidized low-density lipoprotein (ox-LDL) cholesterol significantly up-regulates both the expression of miRNA-223 and L-type calcium channel protein. In contrast, knockdown of miRNA-223 reduced L-type calcium channel protein expression, while genetic knockdown of endogenous miRNA-223 dampened AF vulnerability. Transfection of miRNA-223 by adenovirus-mediated expression enhanced L-type calcium currents and promoted AF in mice while co-injection of a CACNA1C-specific miR-mimic counteracted the effect. Taken together, ox-LDL, as a known factor in AF-associated remodeling, positively regulates miRNA-223 transcription and L-type calcium channel protein expression. Our results implicate a new molecular mechanism for AF in which miRNA-223 can be used as an biomarker of AF rheumatic heart disease. PMID:27488468

  5. Decrease in plasma high-density lipoprotein cholesterol levels at puberty in boys with delayed adolescence: correlation with plasma testosterone levels

    SciTech Connect

    Kirkland, R.T.; Keenan, B.S.; Probstfield, J.L.; Patsch, W.; Lin, T.L.; Clayton, G.W.; Insull, W. Jr.

    1987-01-23

    A three-phase study tested the hypothesis that the decrease in the high-density lipoprotein cholesterol (HDL-C) level observed in boys at puberty is related to an increase in the plasma testosterone concentration. In phase I, 57 boys aged 10 to 17 years were categorized into four pubertal stages based on clinical parameters and plasma testosterone levels. These four groups showed increasing plasma testosterone values and decreasing HDL-C levels. In phase II, 14 boys with delayed adolescence were treated with testosterone enanthate. Plasma testosterone levels during therapy were in the adult male range. Levels of HDL-C decreased by a mean of 7.4 mg/dL (0.20 mmol/L) and 13.7 mg/dL (0.35 mmol/L), respectively, after the first two doses. In phase III, 13 boys with delayed adolescence demonstrated increasing plasma testosterone levels and decreasing HDL-C levels during spontaneous puberty. Levels of HDL-C and apolipoprotein A-1 were correlated during induced and spontaneous puberty. Testosterone should be considered a significant determinant of plasma HDL-C levels during pubertal development.

  6. Effects of Dietary Palmitoleic Acid on Plasma Lipoprotein Profile and Aortic Cholesterol Accumulation Are Similar to Those of Other Unsaturated Fatty Acids in the F1B Golden Syrian Hamster 1–3

    PubMed Central

    Matthan, Nirupa R.; Dillard, Alice; Lecker, Jaime L.; Ip, Blanche; Lichtenstein, Alice H.

    2008-01-01

    The lower susceptibility of palmitoleic acid (16:1) to oxidation compared to PUFA may confer functional advantages with respect to finding acceptable alternatives to partially hydrogenated fats, but limited data are available on its effect on cardiovascular risk factors. This study investigated the effect of diets (10% fat, 0.1% cholesterol, wt:wt) enriched with macadamia [monounsaturated fatty acid (MUFA)16:1], palm (SFA,16:0), canola (MUFA,18:1), or safflower (PUFA,18:2) oils on lipoprotein profiles and aortic cholesterol accumulation in F1B Golden Syrian hamsters (n = 16/group). After 12 wk, 8 hamsters in each group were killed (phase 1). The remaining hamsters fed palm oil were changed to a diet containing coconut oil, while hamsters in the other diet groups continued on their original diets for an additional 6 wk (phase 2). With minor exceptions, the time course and dietary SFA source did not alter the study outcomes. Macadamia oil-fed hamsters had lower non-HDL cholesterol and triglyceride concentrations compared with the palm and coconut oil-fed hamsters and higher HDL-cholesterol compared with the coconut, canola, and safflower oil-fed hamsters. The aortic cholesterol concentration was not affected by dietary fat type. The hepatic cholesterol concentration was higher in the unsaturated compared with the saturated oil-fed hamsters. RBC membrane and aortic cholesteryl ester, triglyceride, and phospholipid fatty acid profiles reflected that of the dietary oil. These data suggest that an oil relatively high in palmitoleic acid does not adversely affect plasma lipoprotein profiles or aortic cholesterol accumulation and was similar to other unsaturated fatty acid-rich oils. PMID:19106316

  7. Effects of dietary palmitoleic acid on plasma lipoprotein profile and aortic cholesterol accumulation are similar to those of other unsaturated fatty acids in the F1B golden Syrian hamster.

    PubMed

    Matthan, Nirupa R; Dillard, Alice; Lecker, Jaime L; Ip, Blanche; Lichtenstein, Alice H

    2009-02-01

    The lower susceptibility of palmitoleic acid (16:1) to oxidation compared to PUFA may confer functional advantages with respect to finding acceptable alternatives to partially hydrogenated fats, but limited data are available on its effect on cardiovascular risk factors. This study investigated the effect of diets (10% fat, 0.1% cholesterol, wt:wt) enriched with macadamia [monounsaturated fatty acid (MUFA)16:1], palm (SFA,16:0), canola (MUFA,18:1), or safflower (PUFA,18:2) oils on lipoprotein profiles and aortic cholesterol accumulation in F1B Golden Syrian hamsters (n = 16/group). After 12 wk, 8 hamsters in each group were killed (phase 1). The remaining hamsters fed palm oil were changed to a diet containing coconut oil, while hamsters in the other diet groups continued on their original diets for an additional 6 wk (phase 2). With minor exceptions, the time course and dietary SFA source did not alter the study outcomes. Macadamia oil-fed hamsters had lower non-HDL cholesterol and triglyceride concentrations compared with the palm and coconut oil-fed hamsters and higher HDL-cholesterol compared with the coconut, canola, and safflower oil-fed hamsters. The aortic cholesterol concentration was not affected by dietary fat type. The hepatic cholesterol concentration was higher in the unsaturated compared with the saturated oil-fed hamsters. RBC membrane and aortic cholesteryl ester, triglyceride, and phospholipid fatty acid profiles reflected that of the dietary oil. These data suggest that an oil relatively high in palmitoleic acid does not adversely affect plasma lipoprotein profiles or aortic cholesterol accumulation and was similar to other unsaturated fatty acid-rich oils. PMID:19106316

  8. Apolipoprotein modulation of streptococcal serum opacity factor activity against human plasma high-density lipoproteins.

    PubMed

    Rosales, Corina; Gillard, Baiba K; Courtney, Harry S; Blanco-Vaca, Francisco; Pownall, Henry J

    2009-08-25

    Human plasma HDL are the target of streptococcal serum opacity factor (SOF), a virulence factor that clouds human plasma. Recombinant (r) SOF transfers cholesteryl esters (CE) from approximately 400,000 HDL particles to a CE-rich microemulsion (CERM), forms a cholesterol-poor HDL-like particle (neo HDL), and releases lipid-free (LF) apo A-I. Whereas the rSOF reaction requires labile apo A-I, the modulation effects of other apos are not known. We compared the products and rates of the rSOF reaction against human HDL and HDL from mice overexpressing apos A-I and A-II. Kinetic studies showed that the reactivity of various HDL species is apo-specific. LpA-I reacts faster than LpA-I/A-II. Adding apos A-I and A-II inhibited the SOF reaction, an effect that was more profound for apo A-II. The rate of SOF-mediated CERM formation was slower against HDL from mice expressing human apos A-I and A-II than against WT mice HDL and slowest against HDL from apo A-II overexpressing mice. The lower reactivity of SOF against HDL containing human apos is due to the higher hydropathy of human apo A-I, particularly its C-terminus relative to mouse apo A-I, and the higher lipophilicity of human apo A-II. The SOF-catalyzed reaction is the first to target HDL rather than its transporters and receptors in a way that enhances reverse cholesterol transport (RCT). Thus, effects of apos on the SOF reaction are highly relevant. Our studies show that the "humanized" apo A-I-expressing mouse is a good animal model for studies of rSOF effects on RCT in vivo.

  9. Reverse cholesterol transport is regulated by varying fatty acyl chain saturation and sphingomyelin content in reconstituted high density lipoproteins

    PubMed Central

    Marmillot, Philippe; Patel, Sanket; Lakshman, M. Raj

    2007-01-01

    Because phospholipid composition of HDL plays a vital role in its reverse cholesterol transport (RCT) function, we studied RCT in vitro (uptake and efflux) with reconstituted HDLs (rHDLs) containing phosphatidylcholine with fatty acids of increasing saturation levels (stearic, oleic, linoleic, linolenic), and without or with sphingomyelin. Uptake significantly increased from basal value when phosphatidylcholine component included up to 50% (%mol) of oleic or linolenic acid, but did not change with linoleic acid. Increasing oleic and linoleic acids to 100% (%mol) significantly decreased uptake, but increasing linolenic acid to the same value did not affect it. Sphingomyelin in rHDL significantly decreased uptake, but only with phosphatidylcholine containing unsaturated fatty acids, and not with saturated fatty acid. Efflux was not affected in a dose-dependent manner when oleic or linoleic acid content was increased, but was significantly increased with levels of linolenic acid up to 25% (%mol) in phosphatidylcholine, and was dramatically lowered with higher levels. Sphingomyelin in rHDL (phosphatidylcholine:sphingomyelin, 20:80, mol:mol) significantly increased efflux only with oleic or linoleic acid-containing rHDLs, compared to efflux without sphingomyelin. In conclusion, enrichment of phosphatidylcholine component up to 25% (%mol) as linolenic acid has a beneficial effect on RCT, while a higher percentage of it or other unsaturated fatty acids seems to be detrimental. Also, high sphingomyelin content decreases uptake with rHDL containing unsaturated fatty acids, whereas it increases efflux for rHDL containing oleic or linoleic acid. These results show for the first time the importance of sphingomyelin in RCT in a well-defined in vitro system. PMID:17224341

  10. What Do My Cholesterol Levels Mean?

    MedlinePlus

    ... Tools & Resources Stroke More What Do My Cholesterol Levels Mean? Updated:Mar 22,2016 High cholesterol can ... a fasting “lipoprotein profile” to measure your cholesterol levels. It assesses several types of fat in the ...

  11. How to Get Your Cholesterol Tested

    MedlinePlus

    ... HDL) cholesterol, low-density lipoprotein (LDL) cholesterol and triglycerides. A small sample of blood will be drawn ... the amount of LDL (bad) cholesterol level and triglycerides can be affected by what you've recently ...

  12. rs7903146 polymorphism at transcription factor 7 like 2 gene is associated with total cholesterol and lipoprotein profile in HIV/hepatitis C virus-coinfected patients.

    PubMed

    Pineda-Tenor, Daniel; Berenguer, Juan; Jiménez-Sousa, María A; Carrero, Ana; García-Álvarez, Mónica; Aldámiz-Echevarria, Teresa; García-Broncano, Pilar; Diez, Cristina; Guzmán-Fulgencio, María; Fernández-Rodríguez, Amanda; Resino, Salvador

    2015-03-01

    Transcription factor 7 like 2 (TCF7L2) rs7903146 polymorphism has been associated with metabolic disturbance and cardiovascular disease. The aim of this study was to analyze the association between TCF7L2 rs7903146 polymorphism and potential disturbances on the lipid profile in human immunodeficiency virus (HIV)/hepatitis C virus (HCV)-coinfected patients. We performed a cross-sectional study on 263 HIV/HVC-coinfected patients. TCF7L2 polymorphism was genotyped by GoldenGate assay. The analysis was performed by linear and logistic regression under a dominant model of inheritance. The variables analyzed were total cholesterol (TC), high-density lipoprotein (HDL-C), low-density lipoprotein (LDL-C), non-HDL-C, and triglycerides. Patients harboring the rs7903146 TT/TC genotype showed a diminished concentration of TC (p=0.003), LDL-C (p=0.004), HDL-C (p=0.012), and non-HDL-C (p=0.013), a lower percentage of TC≥200 mg/dl (p=0.038), and a higher percentage of HDL≤40 mg/dl (p=0.023). In addition, we observed that rs7903146 was differently related to fasting serum lipid levels according to the HCV-genotype (HCV-GT). With regard to HCV-GT1 patients, the rs7903146 TT/TC genotype was associated with lower levels of HDL-C [adjusted arithmetic mean ratio (aAMR)=0.91; p=0.049] and an elevated percentage of patients with HDL-C≤40 mg/dl [adjusted odds ratio (aOR)=3.26; p=0.003]. For HCV-GT3 patients, the rs7903146 TT/TC genotype was associated with lower serum values of TC (aAMR=0.81; p=0.037), LDL-C (aAMR=0.67; p=0.001), and non-HDL-C (aAMR=0.75; p=0.002) and a reduced percentage of TC≥200 mg/dl (aOR=0.089; p=0.037). In conclusion, the TCF7L2 rs7903146 TT/TC genotype was associated with lower levels of TC, LDL, and HDL in HCV-GT3 patients, and lower levels of HDL-C in HCV-GT1 patients, suggesting a role in cardiovascular disease and a potential use as a biomarker in HIV/HCV-coinfected patients. PMID:25353718

  13. rs7903146 Polymorphism at Transcription Factor 7 Like 2 Gene Is Associated with Total Cholesterol and Lipoprotein Profile in HIV/Hepatitis C Virus-Coinfected Patients

    PubMed Central

    Pineda-Tenor, Daniel; Berenguer, Juan; Jiménez-Sousa, María A.; Carrero, Ana; García-Álvarez, Mónica; Aldámiz-Echevarria, Teresa; García-Broncano, Pilar; Diez, Cristina; Guzmán-Fulgencio, María; Fernández-Rodríguez, Amanda

    2015-01-01

    Abstract Transcription factor 7 like 2 (TCF7L2) rs7903146 polymorphism has been associated with metabolic disturbance and cardiovascular disease. The aim of this study was to analyze the association between TCF7L2 rs7903146 polymorphism and potential disturbances on the lipid profile in human immunodeficiency virus (HIV)/hepatitis C virus (HCV)-coinfected patients. We performed a cross-sectional study on 263 HIV/HVC-coinfected patients. TCF7L2 polymorphism was genotyped by GoldenGate assay. The analysis was performed by linear and logistic regression under a dominant model of inheritance. The variables analyzed were total cholesterol (TC), high-density lipoprotein (HDL-C), low-density lipoprotein (LDL-C), non-HDL-C, and triglycerides. Patients harboring the rs7903146 TT/TC genotype showed a diminished concentration of TC (p=0.003), LDL-C (p=0.004), HDL-C (p=0.012), and non-HDL-C (p=0.013), a lower percentage of TC≥200 mg/dl (p=0.038), and a higher percentage of HDL≤40 mg/dl (p=0.023). In addition, we observed that rs7903146 was differently related to fasting serum lipid levels according to the HCV-genotype (HCV-GT). With regard to HCV-GT1 patients, the rs7903146 TT/TC genotype was associated with lower levels of HDL-C [adjusted arithmetic mean ratio (aAMR)=0.91; p=0.049] and an elevated percentage of patients with HDL-C≤40 mg/dl [adjusted odds ratio (aOR)=3.26; p=0.003]. For HCV-GT3 patients, the rs7903146 TT/TC genotype was associated with lower serum values of TC (aAMR=0.81; p=0.037), LDL-C (aAMR=0.67; p=0.001), and non-HDL-C (aAMR=0.75; p=0.002) and a reduced percentage of TC≥200 mg/dl (aOR=0.089; p=0.037). In conclusion, the TCF7L2 rs7903146 TT/TC genotype was associated with lower levels of TC, LDL, and HDL in HCV-GT3 patients, and lower levels of HDL-C in HCV-GT1 patients, suggesting a role in cardiovascular disease and a potential use as a biomarker in HIV/HCV-coinfected patients. PMID:25353718

  14. [Studies on stroke-prone spontaneously hypertensive rats (SHRSP) fed a high-fat and high-cholesterol diet--effects of salt intake on serum lipoprotein and apolipoprotein metabolism].

    PubMed

    Ogawa, H; Nishikawa, T; Fukushima, S; Sasagawa, S

    1989-10-01

    Recently, food intake in Japan has been characterized by an increase in fat intake, especially animal-fat intake and the maintenance of excess salt (sodium chloride) intake. It is generally accepted that the increase in fat intake is closely related to atherosclerosis, and excess salt intake is a high risk factor for the development of hypertension and cerebrovascular lesions. So far, in almost all reports, the increase in fat intake and excess salt intake have been studied independently, and there have been few reports on the combined effects of these two factors. Taking the above things into consideration, it would seem to be very interesting to investigate the effect of excess salt intake on lipid metabolism. In this paper, we studied the effects of excess salt intake on lipoprotein and apolipoprotein metabolisms, using stroke-prone spontaneously hypertensive rats (SHRSP) and normotensive Kyo: Wistar rats (WKY) as model animals. The results obtained were as follows: A significant increase in the concentration of serum total cholesterol (TC) was observed in SHRSP and WKY, when the rats were given a regular diet (CE-2, Clea Japan Inc.) and 1% sodium chloride solution (1% NaCl) as drinking water for 4 weeks. This was accompanied by a tendency toward increases in the concentrations of serum apolipoproteins in both strains. These results suggest that excess salt intake could accelerate the production of serum total lipoproteins in SHRSP and WKY, when the rats are fed a regular diet. Next, 1% NaCl and a high-fat and high-cholesterol diet (HFC diet) were simultaneously given to SHRSP and WKY for 6 weeks. The effects of simultaneous administration on lipoprotein and apolipoprotein metabolisms were compared with those of HFC feeding. One percent NaCl did not markedly affect hypercholesterolemia in WKY, while it induced more marked hypercholesterolemia in SHRSP that was associated with extreme elevations of serum TC and the atherogenic index (A.I.). This deleterious

  15. Beta2-adrenergic activity modulates vascular tone regulation in lecithin:cholesterol acyltransferase knockout mice.

    PubMed

    Manzini, S; Pinna, C; Busnelli, M; Cinquanta, P; Rigamonti, E; Ganzetti, G S; Dellera, F; Sala, A; Calabresi, L; Franceschini, G; Parolini, C; Chiesa, G

    2015-11-01

    Lecithin:cholesterol acyltransferase (LCAT) deficiency is associated with hypoalphalipoproteinemia, generally a predisposing factor for premature coronary heart disease. The evidence of accelerated atherosclerosis in LCAT-deficient subjects is however controversial. In this study, the effect of LCAT deficiency on vascular tone and endothelial function was investigated in LCAT knockout mice, which reproduce the human lipoprotein phenotype. Aortas from wild-type (Lcat(wt)) and LCAT knockout (Lcat(KO)) mice exposed to noradrenaline showed reduced contractility in Lcat(KO) mice (P<0.005), whereas acetylcholine exposure showed a lower NO-dependent relaxation in Lcat(KO) mice (P<0.05). Quantitative PCR and Western blotting analyses suggested an adequate eNOS expression in Lcat(KO) mouse aortas. Real-time PCR analysis indicated increased expression of β2-adrenergic receptors vs wild-type mice. Aorta stimulation with noradrenaline in the presence of propranolol, to abolish the β-mediated relaxation, showed the same contractile response in the two mouse lines. Furthermore, propranolol pretreatment of mouse aortas exposed to L-NAME prevented the difference in responses between Lcat(wt) and Lcat(KO) mice. The results indicate that LCAT deficiency leads to increased β2-adrenergic relaxation and to a consequently decreased NO-mediated vasodilation that can be reversed to guarantee a correct vascular tone. The present study suggests that LCAT deficiency is not associated with an impaired vascular reactivity. PMID:26254103

  16. HNRNPA1 regulates HMGCR alternative splicing and modulates cellular cholesterol metabolism

    PubMed Central

    Yu, Chi-Yi; Theusch, Elizabeth; Lo, Kathleen; Mangravite, Lara M.; Naidoo, Devesh; Kutilova, Mariya; Medina, Marisa W.

    2014-01-01

    3-hydroxy-3-methylglutaryl-Coenzyme A reductase (HMGCR) encodes the rate-limiting enzyme in the cholesterol biosynthesis pathway and is inhibited by statins, a class of cholesterol-lowering drugs. Expression of an alternatively spliced HMGCR transcript lacking exon 13, HMGCR13(−), has been implicated in the variation of plasma LDL-cholesterol (LDL-C) and is the single most informative molecular marker of LDL-C response to statins. Given the physiological importance of this transcript, our goal was to identify molecules that regulate HMGCR alternative splicing. We recently reported gene expression changes in 480 lymphoblastoid cell lines (LCLs) after in vitro simvastatin treatment, and identified a number of statin-responsive genes involved in mRNA splicing. Heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) was chosen for follow-up since rs3846662, an HMGCR SNP that regulates exon 13 skipping, was predicted to alter an HNRNPA1 binding motif. Here, we not only demonstrate that rs3846662 modulates HNRNPA1 binding, but also that sterol depletion of human hepatoma cell lines reduced HNRNPA1 mRNA levels, an effect that was reversed with sterol add-back. Overexpression of HNRNPA1 increased the ratio of HMGCR13(−) to total HMGCR transcripts by both directly increasing exon 13 skipping in an allele-related manner and specifically stabilizing the HMGCR13(−) transcript. Importantly, HNRNPA1 overexpression also diminished HMGCR enzyme activity, enhanced LDL-C uptake and increased cellular apolipoprotein B (APOB). rs1920045, an SNP associated with HNRNPA1 exon 8 alternative splicing, was also associated with smaller statin-induced reduction in total cholesterol from two independent clinical trials. These results suggest that HNRNPA1 plays a role in the variation of cardiovascular disease risk and statin response. PMID:24001602

  17. Common polymorphisms of ATP binding cassette transporter A1, including a functional promoter polymorphism, associated with plasma high density lipoprotein cholesterol levels in Turks.

    PubMed

    Hodoğlugil, Uğur; Williamson, David W; Huang, Yadong; Mahley, Robert W

    2005-12-01

    The role of high levels of high density lipoprotein cholesterol (HDL-C) in protection against development of atherosclerosis is generally attributed to its role in reverse cholesterol transport, and the ATP binding cassette transporter A1 (ABCA1) is a key element of this process. We examined polymorphisms in ABCA1 in Turks, a population characterized by very low HDL-C levels. We discovered 36 variations in ABCA1 and genotyped informative polymorphisms in over 2,300 subjects. The rare alleles of C-14T and V771M polymorphisms were associated with higher HDL-C levels in men and, in combination with the rare alleles of R219K and I883M, respectively, with higher HDL-C in both sexes. Rare alleles of the C-14T and V771M polymorphisms were more frequent in the high HDL-C (>OR=40mg/dl) than in the low HDL-C group (

  18. Differential Benefit of Statin in Secondary Prevention of Acute Myocardial Infarction according to the Level of Triglyceride and High Density Lipoprotein Cholesterol

    PubMed Central

    Kim, Kyung Hwan; Kim, Cheol Hwan; Ahn, Youngkeun; Kim, Young Jo; Cho, Myeong Chan; Kim, Wan; Kim, Jong Jin

    2016-01-01

    Background and Objectives The differential benefit of statin according to the state of dyslipidemia has been sparsely investigated. We sought to address the efficacy of statin in secondary prevention of myocardial infarction (MI) according to the level of triglyceride and high density lipoprotein cholesterol (HDL-C) on admission. Subjects and Methods Acute MI patients (24653) were enrolled and the total patients were divided according to level of triglyceride and HDL-C on admission: group A (HDL-C≥40 mg/dL and triglyceride<150 mg/dL; n=11819), group B (HDL-C≥40 mg/dL and triglyceride≥150 mg/dL; n=3329), group C (HDL-C<40 mg/dL and triglyceride<150 mg/dL; n=6062), and group D (HDL-C<40 mg/dL & triglyceride≥150 mg/dL; n=3443). We evaluated the differential efficacy of statin according to the presence or absence of component of dyslipidemia. The primary end points were major adverse cardiac events (MACE) for 2 years. Results Statin therapy significantly reduced the risk of MACE in group A (hazard ratio=0.676; 95% confidence interval: 0.582-0.785; p<0.001). However, the efficacy of statin was not prominent in groups B, C, or D. In a propensity-matched population, the result was similar. In particular, the benefit of statin in group A was different compared with group D (interaction p=0.042) Conclusion The benefit of statin in patients with MI was different according to the presence or absence of dyslipidemia. In particular, because of the insufficient benefit of statin in patients with MI and dyslipidemia, a different lipid-lowering strategy is necessary in these patients. PMID:27275169

  19. Combined Analysis of Genome Scans of Dutch and Finnish Families Reveals a Susceptibility Locus for High-Density Lipoprotein Cholesterol on Chromosome 16q

    PubMed Central

    Pajukanta, Päivi; Allayee, Hooman; Krass, Kelly L.; Kuraishy, Ali; Soro, Aino; Lilja, Heidi E.; Mar, Rebecca; Taskinen, Marja-Riitta; Nuotio, Ilpo; Laakso, Markku; Rotter, Jerome I.; de Bruin, Tjerk W. A.; Cantor, Rita M.; Lusis, Aldons J.; Peltonen, Leena

    2003-01-01

    Several genomewide screens have been performed to identify novel loci predisposing to unfavorable serum lipid levels and coronary heart disease (CHD). We hypothesized that the accumulating data of these screens in different study populations could be combined to verify which of the identified loci truly harbor susceptibility genes. The power of this strategy has recently been demonstrated with other complex diseases, such as inflammatory bowel disease and asthma. We assessed the largely unknown genetic background of CHD by investigating the most common dyslipidemia predisposing to CHD, familial combined hyperlipidemia (FCHL), affecting 1%–2% of Western populations and 10%–20% of families with premature CHD. To be able to perform a combined data analysis, we unified the diagnostic criteria for FCHL and its component traits and combined the data from two genomewide scans performed in two populations, the Finns and the Dutch. As a result of our pooled data analysis, we identified three chromosomal regions, on chromosomes 2p25.1, 9p23, and 16q24.1, exceeding the statistical significance level of a LOD score >2.0. The 2p25.1 region was detected for the FCHL trait, and the 9p23 and 16q24.1 regions were detected for the low high-density lipoprotein cholesterol (HDL-C) trait. In addition, the previously recognized 1q21 region also obtained additional support in the other study sample, when the triglyceride trait was used. Analysis of the 16q24.1 region resulted in a statistically significant LOD score of 3.6 when the data from Finnish families with low HDL-C were included in the analysis. To search for the underlying gene in the 16q24.1 region, we investigated a novel functional and positional candidate gene, helix/forkhead transcription factor (FOXC2), by sequencing and by genotyping of two single-nucleotide polymorphisms in the families. PMID:12638083

  20. Effects of apolipoprotein A5 haplotypes on the ratio of triglyceride to high-density lipoprotein cholesterol and the risk for metabolic syndrome in Koreans

    PubMed Central

    2014-01-01

    Background Single-nucleotide polymorphisms (SNPs) around the apolipoprotein A5 gene (APOA5) have pleiotropic effects on the levels of triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C). APOA5 SNPs have also been associated with metabolic syndrome (MS). Here, we constructed haplotypes with SNPs spanning APOA5 and ZNF259, which are approximately 1.3 kb apart, to perform association analyses with the risk for MS and the levels of TG and HDL-C in terms of a TG:HDL-C ratio. Methods The effects of three constructed haplotypes (TAA, CGG, and CGA, in the order of rs662799, rs651821, and rs6589566) on the TG:HDL-C ratio and MS were estimated using multiple regression analyses in 2,949 Koreans and in each gender separately (1,082 men and 1,867 women). Results The haplotypes, CGG and CGA, were associated with the TG:HDL-C ratio and the risk of MS development in both genders. That is, the minor alleles of the rs662799 and rs651821 in APOA5, irrespective of which allele was present at rs6589566, had the marked effects. Interestingly, a C–G–A haplotype at these three SNPs had the most marked effects on the TG:HDL-C ratio and the risk of MS development in women. Conclusions We have identified the novel APOA5-ZNF259 haplotype manifesting sex-dependent effects on elevation of the TG:HDL-C ratio as well as the increased risk for MS. PMID:24618354

  1. Effects of red grape juice consumption on high density lipoprotein-cholesterol, apolipoprotein AI, apolipoprotein B and homocysteine in healthy human volunteers.

    PubMed

    Khadem-Ansari, Mohammad H; Rasmi, Yousef; Ramezani, Fatemeh

    2010-01-01

    It has suggested that grape juice consumption has lipid- lowering effect and it is associated with a decreased risk of heart disease. We aimed to evaluate the effects of red grape juice (RGj) consumption on high density lipoprotein-cholesterol (HDL-C), apolipoprotein AI (apoAI), apolipoprotein B (apoB) and homocysteine (Hcy) levels in healthy human volunteers. Twenty six healthy and nonsmoking males, aged between 25-60 years, who were under no medication asked to consume 150 ml of RGj twice per day for one month. Serum HDL-C, apoAI, apoB and plasma Hcy levels were measured before and after one month RGj consumption. HDL-C levels after RGj consumption were significantly higher than the corresponding levels before the RGj consumption (41.44 ± 4.50 and 44.37 ± 4.30 mg/dl; P<0.0001). Also, apoB was significantly increased after RGj consumption (149.0 ± 22.35 and 157.19 ± 18.60 mg/dl; P<0.002). But apoAI levels were not changed significantly before and after of RGj consumption (154.27 ± 21.55 and 155.35 ± 21.07 mg/dl; P>0.05). Hcy levels were decreased after RGj consumption (7.70 ± 2.80 and 6.20 ± 2.30 µmol/l; P<0.001). The present study demonstrates that RGj consumption can significantly increase serum HDL-C levels and decrease Hcy levels. These findings may have important implications for the prevention of atherosclerosis in healthy individuals. PMID:21633724

  2. Effect of Low-Density Lipoprotein Cholesterol Lowering by Ezetimibe/Simvastatin on Outcome Incidence: Overview, Meta-Analyses, and Meta-Regression Analyses of Randomized Trials.

    PubMed

    Thomopoulos, Costas; Skalis, George; Michalopoulou, Helena; Tsioufis, Costas; Makris, Thomas

    2015-12-01

    This analysis investigated the extent of different outcome reductions from low-density lipoprotein cholesterol (LDL-C) lowering following ezetimibe/simvastatin treatment and the proportionality of outcome to LDL-C reductions. The authors searched PubMed between 1997 and mid-June 2015 (any language) and the Cochrane Library to identify all randomized controlled trials comparing ezetimibe/simvastatin with placebo or less intensive LDL-C lowering. Risk ratios (RR) and 95% confidence intervals (CIs), standardized to 20 mg/dL LDL-C reduction, were calculated for 5 primary outcomes (fatal and nonfatal) and 4 secondary outcomes (non-cardiovascular [CV] death, cancer, myopathy, and hepatopathy). Five ezetimibe/simvastatin RCTs (30 051 individuals) were eligible, 2 comparing ezetimibe/simvastatin vs placebo and 3 vs less intensive treatment. Outcomes reduced almost to the same extent were stroke (RR: -13%, 95% CI: -21% to -3%), coronary heart disease (CHD; RR: -12%, 95% CI: -19% to -5%), and composite of stroke and CHD (RR: -14%, 95% CI: -20% to -8%). Absolute risk reductions: 5 strokes, 10 CHD events, and 16 stroke and CHD events prevented for every 1000 patients treated for 5 years. Residual risk was almost 7× higher than absolute risk reduction for all the above outcomes. All death outcomes were not reduced, and secondary outcomes did not differ between groups. Logarithmic risk ratios were not associated with LDL-C lowering. Our meta-analysis provides evidence that, in patients with different CV disease burden, major CV events are safely reduced by LDL-C lowering with ezetimibe/simvastatin, while raising the hypothesis that the extent of LDL-C lowering might not be accompanied by incremental clinical-event reduction.

  3. Identification of Sequence Variation in the Apolipoprotein A2 Gene and Their Relationship with Serum High-Density Lipoprotein Cholesterol Levels

    PubMed Central

    Bandarian, Fatemeh; Daneshpour, Maryam Sadat; Hedayati, Mehdi; Naseri, Mohsen; Azizi, Fereidoun

    2016-01-01

    Background: Apolipoprotein A2 (APOA2) is the second major apolipoprotein of the high-density lipoprotein cholesterol (HDL-C). The study aim was to identify APOA2 gene variation in individuals within two extreme tails of HDL-C levels and its relationship with HDL-C level. Methods: This cross-sectional survey was conducted on participants from Tehran Glucose and Lipid Study (TLGS) at Research Institute for Endocrine Sciences, Tehran, Iran from April 2012 to February 2013. In total, 79 individuals with extreme low HDL-C levels (≤5th percentile for age and gender) and 63 individuals with extreme high HDL-C levels (≥95th percentile for age and gender) were selected. Variants were identified using DNA amplification and direct sequencing. Results: Screen of all exons and the core promoter region of APOA2 gene identified nine single nucleotide substitutions and one microsatellite; five of which were known and four were new variants. Of these nine variants, two were common tag single nucleotide polymorphisms (SNPs) and seven were rare SNPs. Both exonic substitutions were missense mutations and caused an amino acid change. There was a significant association between the new missense mutation (variant Chr.1:16119226, Ala98Pro) and HDL-C level. Conclusion: None of two common tag SNPs of rs6413453 and rs5082 contributes to the HDL-C trait in Iranian population, but a new missense mutation in APOA2 in our population has a significant association with HDL-C. PMID:26590203

  4. Thyroid function modifies the association between ratio of triglyceride to high-density lipoprotein cholesterol and renal function: a multicenter cross-sectional study

    PubMed Central

    Yuan, Zhongshang; Zhao, Meng; Zhang, Bingchang; Zhang, Haiqing; Zhang, Xu; Guan, Qingbo; Ning, Guang; Gao, Ling; Xue, Fuzhong; Zhao, Jiajun

    2015-01-01

    Hypothyroidism was confirmed to be associated with both dyslipidemia and renal dysfunction. However, the impact of thyroid function on the relationship between serum lipid levels and renal function has never been given sufficient attention. In this large-scale multicenter cross-sectional study, the ratio of triglyceride to high-density lipoprotein cholesterol (TG/HDL) and the prevalence of hypothyroidism in CKD subjects were significantly higher than those in non-CKD ones (P < 0.001). After adjustment for potential confounding factors, TG/HDL was shown to be significantly associated with serum Cr levels (β = 0.551; 95%CI, 0.394–0.708), and eGFR (β = −0.481; 95%CI, −0.731–−0.230). The risk for CKD was significantly increased as TG/HDL ratio was elevated (adjusted odds ratio = 1.20; 95%CI, 1.11–1.27). These significant associations were found among subjects with euthyroidism and hypothyroidism rather than hyperthyroidism. Furthermore, the associations between TG/HDL and Cr or CKD status were significantly greater in hypothyroidism than those in euthyroidism (P < 0.05). These results suggested that elevated TG/HDL ratio was associated with renal dysfunction; it exhibited a significantly stronger association with Cr and CKD in hypothyroidism than in euthyroidism. Therefore, more attention should be paid on lipid profile to prevent or delay the occurrence and progression of renal dysfunction, especially for those with hypothyroidism. PMID:26179571

  5. Thyroid function modifies the association between ratio of triglyceride to high-density lipoprotein cholesterol and renal function: a multicenter cross-sectional study.

    PubMed

    Yuan, Zhongshang; Zhao, Meng; Zhang, Bingchang; Zhang, Haiqing; Zhang, Xu; Guan, Qingbo; Ning, Guang; Gao, Ling; Xue, Fuzhong; Zhao, Jiajun

    2015-01-01

    Hypothyroidism was confirmed to be associated with both dyslipidemia and renal dysfunction. However, the impact of thyroid function on the relationship between serum lipid levels and renal function has never been given sufficient attention. In this large-scale multicenter cross-sectional study, the ratio of triglyceride to high-density lipoprotein cholesterol (TG/HDL) and the prevalence of hypothyroidism in CKD subjects were significantly higher than those in non-CKD ones (P < 0.001). After adjustment for potential confounding factors, TG/HDL was shown to be significantly associated with serum Cr levels (β = 0.551; 95%CI, 0.394-0.708), and eGFR (β = -0.481; 95%CI, -0.731--0.230). The risk for CKD was significantly increased as TG/HDL ratio was elevated (adjusted odds ratio = 1.20; 95%CI, 1.11-1.27). These significant associations were found among subjects with euthyroidism and hypothyroidism rather than hyperthyroidism. Furthermore, the associations between TG/HDL and Cr or CKD status were significantly greater in hypothyroidism than those in euthyroidism (P < 0.05). These results suggested that elevated TG/HDL ratio was associated with renal dysfunction; it exhibited a significantly stronger association with Cr and CKD in hypothyroidism than in euthyroidism. Therefore, more attention should be paid on lipid profile to prevent or delay the occurrence and progression of renal dysfunction, especially for those with hypothyroidism. PMID:26179571

  6. Normocaloric Low Cholesterol Diet Modulates Th17/Treg Balance in Patients with Chronic Hepatitis C Virus Infection

    PubMed Central

    Maggio, Roberta; Viscomi, Carmela; Andreozzi, Paola; D'Ettorre, Gabriella; Viscogliosi, Giovanni; Barbaro, Barbara; Gori, Manuele; Vullo, Vincenzo; Balsano, Clara

    2014-01-01

    Hepatitis C virus (HCV) infection is associated with hepatic and extrahepatic manifestations, including immunological disorders. Chronic Hepatitis C (CHC) is often characterized by cholesterol and lipid metabolism alterations, leading to hepatic steatosis. Cholesterol metabolism, in fact, is crucial for the viral life cycle. Recent works described that a higher dietary cholesterol intake is associated with the progression of HCV-related liver disease. CHC patients have increased levels of T helper 17 (Th17)-cells, a lymphocytic population involved in the pathogenesis of liver inflammation and autoimmune hepatitis. The balance between Th17 and regulatory T (Treg) cells is crucial for chronic inflammation and autoimmunity. Th17-cell differentiation is deeply influenced by the activation LXRs, nuclear receptors modulating cholesterol homeostasis. Moreover, HCV may affect these nuclear receptors, and cholesterol metabolism, through both direct and indirect mechanisms. On these bases, we hypothesized that modulation of cholesterol levels through Normocaloric Low Cholesterol Diet (NLCD) may represent an innovative strategy to reduce the progression of HCV infection, through the modulation of peripheral Th17/Treg balance. To this end, we performed a pilot study to investigate whether a Normocaloric Low Cholesterol Diet may be able to modulate Th17/Treg balance in patients affected by chronic HCV infection. After 30 days of NLCD CHC patients showed a significant reduction in Th17 cells frequency, which correlated with strong reduction of IL-17 and IL-22 serum levels. At the same time, we appreciated an increase in the percentage of Treg cells, thus improving Treg/Th17balance. Moreover, we observed an increased expression of LXRs and their target genes: SREBP-1c and ABCA-1. In conclusion, NLCD finely regulates Th17/Treg balance, improving immune system response in CHC patients. This study could pave the way for new treatments of CHC patients, suggesting that change in

  7. Phytosterols, Phytostanols, and Lipoprotein Metabolism

    PubMed Central

    Gylling, Helena; Simonen, Piia

    2015-01-01

    The efficacy of phytosterols and phytostanols added to foods and food supplements to obtain significant non-pharmacologic serum and low density lipoprotein (LDL) cholesterol reduction is well documented. Irrespective of age, gender, ethnic background, body weight, background diet, or the cause of hypercholesterolemia and, even added to statin treatment, phytosterols and phytostanols at 2 g/day significantly lower LDL cholesterol concentration by 8%–10%. They do not affect the concentrations of high density lipoprotein cholesterol, lipoprotein (a) or serum proprotein convertase subtilisin/kexin type 9. In some studies, phytosterols and phytostanols have modestly reduced serum triglyceride levels especially in subjects with slightly increased baseline concentrations. Phytosterols and phytostanols lower LDL cholesterol by displacing cholesterol from mixed micelles in the small intestine so that cholesterol absorption is partially inhibited. Cholesterol absorption and synthesis have been carefully evaluated during phytosterol and phytostanol supplementation. However, only a few lipoprotein kinetic studies have been performed, and they revealed that LDL apoprotein B-100 transport rate was reduced. LDL particle size was unchanged, but small dense LDL cholesterol concentration was reduced. In subjects with metabolic syndrome and moderate hypertriglyceridemia, phytostanols reduced not only non- high density lipoprotein (HDL) cholesterol concentration but also serum triglycerides by 27%, and reduced the large and medium size very low density lipoprotein particle concentrations. In the few postprandial studies, the postprandial lipoproteins were reduced, but detailed studies with apoprotein B-48 are lacking. In conclusion, more kinetic studies are required to obtain a more complete understanding of the fasting and postprandial lipoprotein metabolism caused by phytosterols and phytostanols. It seems obvious, however, that the most atherogenic lipoprotein particles will be

  8. Baseline characteristics of participants in the JUPITER trial, a randomized placebo-controlled primary prevention trial of statin therapy among individuals with low low-density lipoprotein cholesterol and elevated high-sensitivity C-reactive protein.

    PubMed

    Ridker, Paul M; Fonseca, Francisco A H; Genest, Jacques; Gotto, Antonio M; Kastelein, John J P; Khurmi, Nardev S; Koenig, Wolfgang; Libby, Peter; Lorenzatti, Alberto J; Nordestgaard, Borge G; Shepherd, James; Willerson, James T; Glynn, Robert J

    2007-12-01

    The Justification for the Use of statins in Primary prevention: an Intervention Trial Evaluating Rosuvastatin (JUPITER) is a randomized, double-blind, placebo-controlled primary prevention trial of statin therapy among persons with average to low levels of low-density lipoprotein (LDL) cholesterol who are at increased cardiovascular risk due to elevated plasma concentrations of the inflammatory biomarker high-sensitivity C-reactive protein (hs-CRP). A total of 17,802 persons with LDL cholesterol<130 mg/dl (3.36 mmol/L) and hs-CRP>or=2 mg/L were recruited from 26 countries and randomly allocated to 20 mg/day rosuvastatin or placebo. In contrast to previous studies of statin therapy in primary prevention, JUPITER is evaluating a group with modest plasma concentrations of LDL cholesterol (median 108 mg/dl, interquartile range 94 to 119). Further, the trial includes 6,801 women (38.2%) and 5,577 participants with metabolic syndrome (32.1%). Thus, in addition to broadening our understanding of statin therapy and inflammation, the JUPITER trial will provide important and clinically relevant information on primary prevention among patients who do not currently qualify for lipid-lowering therapy. In conclusion, as 20 mg of rosuvastatin can reduce LDL cholesterol by up to 50%, JUPITER will also provide crucial safety data for several thousand patients who should achieve LDL cholesterol levels<50 mg/dl on a long-term basis.

  9. IRAK regulates macrophage foam cell formation by modulating genes involved in cholesterol uptake and efflux.

    PubMed

    Rana, Minakshi; Kumar, Amit; Tiwari, Rajiv Lochan; Singh, Vishal; Chandra, Tulika; Dikshit, Madhu; Barthwal, Manoj Kumar

    2016-07-01

    Interleukin-1 receptor-associated kinase-1 (IRAK1) is linked to the pathogenesis of atherosclerosis; however, its role in macrophage foam cell formation is not known. Therefore, the present study investigated the role of IRAK1 in lipid uptake, biosynthesis, and efflux in THP-1 derived macrophages and human monocyte-derived macrophages (HMDMs). Ox-LDL (40 μg/mL, 15 minutes-48 hours) treatment induced time-dependent increase in IRAK1, IRAK4, and Stat1 activation in THP-1 derived macrophages. IRAK1/4 inhibitor (INH) or IRAK1 siRNA significantly attenuated cholesterol accumulation, DiI-Ox-LDL binding, and uptake while cholesterol efflux to apoAI and HDL was enhanced in THP-1 derived macrophages and HMDMs. Ox-LDL treatment significantly increased the mRNA expression of CD36, LOX-1, SR-A, ABCA1, ABCG1, Caveolin-1, CYP27A1 while that of SR-BI was decreased. IRAK1/4 inhibition or IRAK1 knockdown, however, attenuated Ox-LDL-induced CD36 expression; augmented ABCA1 and ABCG1 expression while expression of others was unaffected in THP-1 derived macrophages and HMDMs. Moreover, IRAK1/4 inhibition had no significant effect on genes involved in lipid biosynthesis. In IRAK1/4 INH pre-treated THP-1 derived macrophages Ox-LDL-induced Stat1 phosphorylation and its binding to CD36 promoter was significantly attenuated while LXRα expression and its binding to the ABCA1/ABCG1 locus, NFATc2 activation and its binding to ABCA1 locus was enhanced. The present study thus demonstrates that IRAK regulates lipid accumulation by modulating CD36-mediated uptake and ABCA1-, ABCG1-dependent cholesterol efflux. Therefore, IRAK1 can be a potential target for preventing macrophage foam cell formation. PMID:27270491

  10. Pitavastatin Differentially Modulates MicroRNA-Associated Cholesterol Transport Proteins in Macrophages.

    PubMed

    Zhang, Haijun; Lamon, Brian D; Moran, George; Sun, Tao; Gotto, Antonio M; Hajjar, David P

    2016-01-01

    There is emerging evidence identifying microRNAs (miRNAs) as mediators of statin-induced cholesterol efflux, notably through the ATP-binding cassette transporter A1 (ABCA1) in macrophages. The objective of this study was to assess the impact of an HMG-CoA reductase inhibitor, pitavastatin, on macrophage miRNAs in the presence and absence of oxidized-LDL, a hallmark of a pro-atherogenic milieu. Treatment of human THP-1 cells with pitavastatin prevented the oxLDL-mediated suppression of miR-33a, -33b and -758 mRNA in these cells, an effect which was not uniquely attributable to induction of SREBP2. Induction of ABCA1 mRNA and protein by oxLDL was inhibited (30%) by pitavastatin, while oxLDL or pitavastatin alone significantly induced and repressed ABCA1 expression, respectively. These findings are consistent with previous reports in macrophages. miRNA profiling was also performed using a miRNA array. We identified specific miRNAs which were up-regulated (122) and down-regulated (107) in THP-1 cells treated with oxLDL plus pitavastatin versus oxLDL alone, indicating distinct regulatory networks in these cells. Moreover, several of the differentially expressed miRNAs identified are functionally associated with cholesterol trafficking (six miRNAs in cells treated with oxLDL versus oxLDL plus pitavastatin). Our findings indicate that pitavastatin can differentially modulate miRNA in the presence of oxLDL; and, our results provide evidence that the net effect on cholesterol homeostasis is mediated by a network of miRNAs. PMID:27415822

  11. Pitavastatin Differentially Modulates MicroRNA-Associated Cholesterol Transport Proteins in Macrophages

    PubMed Central

    Moran, George; Sun, Tao; Gotto, Antonio M.; Hajjar, David P.

    2016-01-01

    There is emerging evidence identifying microRNAs (miRNAs) as mediators of statin-induced cholesterol efflux, notably through the ATP-binding cassette transporter A1 (ABCA1) in macrophages. The objective of this study was to assess the impact of an HMG-CoA reductase inhibitor, pitavastatin, on macrophage miRNAs in the presence and absence of oxidized-LDL, a hallmark of a pro-atherogenic milieu. Treatment of human THP-1 cells with pitavastatin prevented the oxLDL-mediated suppression of miR-33a, -33b and -758 mRNA in these cells, an effect which was not uniquely attributable to induction of SREBP2. Induction of ABCA1 mRNA and protein by oxLDL was inhibited (30%) by pitavastatin, while oxLDL or pitavastatin alone significantly induced and repressed ABCA1 expression, respectively. These findings are consistent with previous reports in macrophages. miRNA profiling was also performed using a miRNA array. We identified specific miRNAs which were up-regulated (122) and down-regulated (107) in THP-1 cells treated with oxLDL plus pitavastatin versus oxLDL alone, indicating distinct regulatory networks in these cells. Moreover, several of the differentially expressed miRNAs identified are functionally associated with cholesterol trafficking (six miRNAs in cells treated with oxLDL versus oxLDL plus pitavastatin). Our findings indicate that pitavastatin can differentially modulate miRNA in the presence of oxLDL; and, our results provide evidence that the net effect on cholesterol homeostasis is mediated by a network of miRNAs. PMID:27415822

  12. Modulation of the Isoprenoid/Cholesterol Biosynthetic Pathway During Neuronal Differentiation In Vitro.

    PubMed

    Cartocci, Veronica; Segatto, Marco; Di Tunno, Ilenia; Leone, Stefano; Pfrieger, Frank W; Pallottini, Valentina

    2016-09-01

    During differentiation, neurons acquire their typical shape and functional properties. At present, it is unclear, whether this important developmental step involves metabolic changes. Here, we studied the contribution of the mevalonate (MVA) pathway to neuronal differentiation using the mouse neuroblastoma cell line N1E-115 as experimental model. Our results show that during differentiation, the activity of 3-hydroxy 3-methylglutaryl Coenzyme A reductase (HMGR), a key enzyme of MVA pathway, and the level of Low Density Lipoprotein receptor (LDLr) decrease, whereas the level of LDLr-related protein-1 (LRP1) and the dimerization of Scavanger Receptor B1 (SRB-1) rise. Pharmacologic inhibition of HMGR by simvastatin accelerated neuronal differentiation by modulating geranylated proteins. Collectively, our data suggest that during neuronal differentiation, the activity of the MVA pathway decreases and we postulate that any interference with this process impacts neuronal morphology and function. Therefore, the MVA pathway appears as an attractive pharmacological target to modulate neurological and metabolic symptoms of developmental neuropathologies. J. Cell. Biochem. 117: 2036-2044, 2016. © 2016 Wiley Periodicals, Inc. PMID:27392312

  13. Modulation of the Isoprenoid/Cholesterol Biosynthetic Pathway During Neuronal Differentiation In Vitro.

    PubMed

    Cartocci, Veronica; Segatto, Marco; Di Tunno, Ilenia; Leone, Stefano; Pfrieger, Frank W; Pallottini, Valentina

    2016-09-01

    During differentiation, neurons acquire their typical shape and functional properties. At present, it is unclear, whether this important developmental step involves metabolic changes. Here, we studied the contribution of the mevalonate (MVA) pathway to neuronal differentiation using the mouse neuroblastoma cell line N1E-115 as experimental model. Our results show that during differentiation, the activity of 3-hydroxy 3-methylglutaryl Coenzyme A reductase (HMGR), a key enzyme of MVA pathway, and the level of Low Density Lipoprotein receptor (LDLr) decrease, whereas the level of LDLr-related protein-1 (LRP1) and the dimerization of Scavanger Receptor B1 (SRB-1) rise. Pharmacologic inhibition of HMGR by simvastatin accelerated neuronal differentiation by modulating geranylated proteins. Collectively, our data suggest that during neuronal differentiation, the activity of the MVA pathway decreases and we postulate that any interference with this process impacts neuronal morphology and function. Therefore, the MVA pathway appears as an attractive pharmacological target to modulate neurological and metabolic symptoms of developmental neuropathologies. J. Cell. Biochem. 117: 2036-2044, 2016. © 2016 Wiley Periodicals, Inc.

  14. A new framework for reverse cholesterol transport: Non-biliary contributions to reverse cholesterol transport

    PubMed Central

    Temel, Ryan E; Brown, J Mark

    2010-01-01

    Reduction of low-density lipoprotein-cholesterol through statin therapy has only modestly decreased coronary heart disease (CHD)-associated mortality in developed countries, which has prompted the search for alternative therapeutic strategies for CHD. Major efforts are now focused on therapies that augment high-density lipoprotein (HDL)-mediated reverse cholesterol transport (RCT), and ultimately increase the fecal disposal of cholesterol. The process of RCT has long been thought to simply involve HDL-mediated delivery of peripheral cholesterol to the liver for biliary excretion out of the body. However, recent studies have revealed a novel pathway for RCT that does not rely on biliary secretion. This non-biliary pathway rather involves the direct excretion of cholesterol by the proximal small intestine. Compared to RCT therapies that augment biliary sterol loss, modulation of non-biliary fecal sterol loss through the intestine is a much more attractive therapeutic strategy, given that excessive biliary cholesterol secretion can promote gallstone formation. However, we are at an early stage in understanding the molecular mechanisms regulating the non-biliary pathway for RCT, and much additional work is required in order to effectively target this pathway for CHD prevention. The purpose of this review is to discuss our current understanding of biliary and non-biliary contributions to RCT with particular emphasis on the possibility of targeting the intestine as an inducible cholesterol secretory organ. PMID:21157970

  15. The ATP-binding cassette transporter-2 (ABCA2) regulates esterification of plasma membrane cholesterol by modulation of sphingolipid metabolism

    PubMed Central

    Davis, Warren

    2015-01-01

    The ATP-binding cassette transporters are a large family (~ 48 genes divided into seven families A–G) of proteins that utilize the energy of ATP-hydrolysis to pump substrates across lipid bilayers against a concentration gradient. The ABC “A” subfamily is comprised of 13 members and transport sterols, phospholipids and bile acids. ABCA2 is the most abundant ABC transporter in human and rodent brain with highest expression in oligodendrocytes, although it is also expressed in neurons. Several groups have studied a possible connection between ABCA2 and Alzheimer’s disease as well as early atherosclerosis. ABCA2 expression levels have been associated with changes in cholesterol and sphingolipid metabolism. In this paper, we hypothesized that ABCA2 expression level may regulate esterification of plasma membrane-derived cholesterol by modulation of sphingolipid metabolism. ABCA2 overexpression in N2a neuroblastoma cells was associated with an altered bilayer distribution of the sphingolipid ceramide that inhibited acylCoA:cholesterol acyltransferase (ACAT) activity and cholesterol esterification. In contrast, depletion of endogenous ABCA2 in the rat schwannoma cell line D6P2T increased esterification of plasma membrane cholesterol following treatment with exogenous bacterial sphingomyelinase. These findings suggest that control of ABCA2 expression level may be a key locus of regulation for esterification of plasma membrane-derived cholesterol through modulation of sphingolipid metabolism. PMID:24201375

  16. Differential Modulation of Membrane Structure and Fluctuations by Plant Sterols and Cholesterol

    PubMed Central

    Hodzic, Aden; Rappolt, Michael; Amenitsch, Heinz; Laggner, Peter; Pabst, Georg

    2008-01-01

    We have studied the concentration and temperature dependent influence of cholesterol, stigmasterol, and sitosterol on the global structure and the bending fluctuations of fluid dimyristoyl phosphatidylcholine and palmitoyl oleoyl phosphatidylcholine bilayers applying small-angle x-ray scattering, as well as dilatometry and ultrasound velocimetry. Independent of the lipid matrix, cholesterol was found to be most efficient in modulating bilayer thickness and elasticity, followed by sitosterol and stigmasterol. This can be attributed to the additional ethyl groups and double bond at the C17 alkyl side-chain of the two plant sterols. Hence, it seems that some flexibility of the sterol hydrocarbon chain is needed to accommodate within the lipid bilayer. In addition, we did not observe two populations of membranes within the putative liquid-ordered/liquid-disordered phase coexistence regime of binary sterol/lipid mixtures. Instead, the diffraction patterns could be interpreted in terms of a uniform phase. This lends further support to the idea of compositional fluctuations of unstable sterol rich domains recently brought up by fluorescence microscopy experiments, which contrasts the formation of stable domains within the miscibility gap of binary lipid/sterol mixtures. PMID:18234811

  17. A VOYAGER Meta-Analysis of the Impact of Statin Therapy on Low-Density Lipoprotein Cholesterol and Triglyceride Levels in Patients With Hypertriglyceridemia.

    PubMed

    Karlson, Björn W; Palmer, Michael K; Nicholls, Stephen J; Lundman, Pia; Barter, Philip J

    2016-05-01

    Elevated triglyceride (TG) levels are associated with increased cardiovascular disease risk. In patients with mild-to-moderate hypertriglyceridemia, defined by the European Atherosclerosis Society Consensus Panel as a TG level of 177 to 885 mg/dl (2.0 to 10.0 mmol/L), low-density lipoprotein cholesterol (LDL-C) reduction remains the primary treatment goal. Using data from the indiVidual patient meta-analysis Of statin therapY in At risk Groups: Effects of Rosuvastatin, atorvastatin and simvastatin (VOYAGER) meta-analysis, we analyzed LDL-C and TG reductions in patients with baseline TG ≥177 mg/dl (≥2.0 mmol/L). Least squares mean percentage change from baseline in LDL-C and TG was compared using 15,800 patient exposures to rosuvastatin 5 to 40 mg, atorvastatin 10 to 80 mg, and simvastatin 10 to 80 mg in patients with baseline TG ≥177 mg/dl (≥2.0 mmol/L). Comparisons were made using mixed-effects models with data only from studies directly comparing treatments by randomized design. Mean LDL-C reductions ranged from -26.9% to -55.5%. Rosuvastatin 10 to 40 mg resulted in significantly greater LDL-C reductions than equal or double doses of atorvastatin and simvastatin (p <0.05). Mean TG reductions ranged from -15.1% to -31.3%. Rosuvastatin 10 mg resulted in significantly greater TG reductions than atorvastatin 10 mg (p <0.05). Rosuvastatin 20 and 40 mg resulted in TG reductions similar to those with equal doses of atorvastatin. Rosuvastatin 10 to 40 mg resulted in significantly greater TG reductions than equal or double doses of simvastatin (p <0.05). In conclusion, in patients with hypertriglyceridemia, LDL-C reduction was substantial and dependent on the choice and dose of statin. TG reduction was numerically less than for LDL-C, and additional TG-lowering therapy may be considered to further reduce residual cardiovascular risk.

  18. Safety profile of subjects treated to very low low-density lipoprotein cholesterol levels (<30 mg/dl) with rosuvastatin 20 mg daily (from JUPITER).

    PubMed

    Everett, Brendan M; Mora, Samia; Glynn, Robert J; MacFadyen, Jean; Ridker, Paul M

    2014-12-01

    Recent US guidelines expand the indications for high-intensity statin therapy, yet data on the safety of attaining very low-density lipoprotein cholesterol (LDL-C) levels are scarce. Among 16,304 participants in the Justification for the Use of Statins in Prevention: An Intervention Trial Evaluating Rosuvastatin (JUPITER) with on-treatment LDL-C levels, we identified 767 who did and 7,387 who did not achieve LDL-C <30 mg/dl on rosuvastatin 20 mg daily and 718 participants who did and 7,436 who did not achieve LDL-C reductions of ≥70% on rosuvastatin, and 8,150 allocated to placebo. In participants with an LDL-C <30 mg/dl, we observed an increase in the risk of physician-reported type 2 diabetes with an adjusted hazard ratio (95% confidence interval) of 1.56 (1.09 to 2.23, p = 0.01) and physician-reported hematuria (hazard ratio 2.10 [1.39 to 3.19], p <0.001) compared with rosuvastatin-treated participants with LDL-C ≥30 mg/dl. There was also an increased risk of certain musculoskeletal, hepatobiliary, and psychiatric disorders. No difference in renal failure, cancer, memory impairment, or hemorrhagic stroke was observed, although there were few events in these categories. In rosuvastatin-treated participants, achieving LDL-C reduction ≥70% versus <70% did not appear to be associated with increased risk of hepatobiliary, renal, or urinary disorders. In conclusion, in this post hoc analysis in the JUPITER, achieving LDL-C levels <30 mg/dl with high-intensity statin therapy appeared to be generally well tolerated but associated with certain adverse events, including more physician-reported diabetes, hematuria, hepatobiliary disorders, and insomnia. These data may guide the monitoring of patients on intensive statin therapy and adverse events in trials of therapies that lead to very low LDL-C levels.

  19. Relation of Combined Non-High-Density Lipoprotein Cholesterol and Apolipoprotein B With Atherosclerosis in Adults With Type 1 Diabetes Mellitus.

    PubMed

    Bjornstad, Petter; Eckel, Robert H; Pyle, Laura; Rewers, Marian; Maahs, David M; Snell-Bergeon, Janet K

    2015-10-01

    Apolipoprotein B (apoB) and non-high-density lipoprotein cholesterol (non-HDL-C) are cardiovascular disease risk markers, although data in adults with type 1 diabetes mellitus (DM) are limited. We hypothesized that elevated apoB and non-HDL-C would be associated with greater odds of coronary artery calcification progression (CACp), a measure of coronary atherosclerosis, than either category alone in adults with type 1 DM. We grouped subjects with type 1 DM (n = 652) into 4 groups: elevated apoB (≥90 mg/dl) and elevated non-HDL-C (≥130 mg/dl), elevated non-HDL-C alone, elevated apoB alone, and normal apoB and non-HDL-C. We used logistic regression to examine the associations between the groups and CACp for a period of 6 years. We performed sensitivity analyses with elevated apoB and non-HDL-C redefined as at or more than the cohort means (91.4 and 119.0 mg/dl, respectively). Subjects with elevated apoB and non-HDL-C had greater odds of CACp compared with those with normal apoB and non-HDL-C (odds ratio 1.90, 95% confidence interval 1.15 to 3.15) and compared with subjects with elevated apoB alone (odds ratio 2.86, 95% confidence interval 1.43 to 5.74) adjusting for age, gender, duration, hemoglobin A1c, and statins. Similar results were obtained with elevated apoB and non-HDL-C defined as at or more than the cohort means. In conclusion, elevated apoB and non-HDL-C carry a greater risk of atherosclerosis than elevated apoB in the absence of elevated non-HDL-C in adults with type 1 DM. These data suggest that apoB and non-HDL-C should be viewed as complementary rather than competitive indexes of cardiovascular disease risk in type 1 DM. PMID:26251001

  20. Glucose and low-density lipoprotein cholesterol lowering in elderly patients with type 2 diabetes: focus on combination therapy with colesevelam HCl.

    PubMed

    Marrs, Joel C

    2012-05-01

    The prevalence of type 2 diabetes mellitus is high among the elderly population. Treatment of elderly patients with type 2 diabetes presents challenges because of co-morbidities and the potential increase in the risk of adverse effects. Hyperlipidaemia is also common in the elderly population. Glucose- and lipid-lowering treatment in elderly patients should be individualized on the basis of the patient's life expectancy, health status and cardiovascular risk factors, and evidence-based guideline recommendations. Because elderly patients often have impaired renal and hepatic function, careful considerations must be made when selecting appropriate glucose- and lipid-lowering therapy. There are a number of potential safety issues associated with various glucose- and lipid-lowering therapies that are relevant to elderly patients, including increased risk of heart failure exacerbations, weight loss, increased risk of hypoglycaemia, increased risk of myopathy, and contraindications of some agents in patients with hepatic or renal impairment. The bile acid sequestrant colesevelam HCl is unique compared with other glucose- and lipid-lowering therapies because it is the only product approved by the US Food and Drug Administration, as an adjunct to diet and exercise, to lower both glucose and low-density lipoprotein cholesterol (LDL-C) in adults with type 2 diabetes and primary hyperlipidaemia, respectively. Furthermore, colesevelam has been shown to have similar glucose- and lipid-lowering efficacy in patients aged <65 years and those aged ≥65 years. Colesevelam was not associated with weight gain, was associated with a low incidence of hypoglycaemia, and can be safely combined with a broad range of glucose-lowering agents (metformin, sulfonylureas and insulin) and lipid-lowering statins. Currently, colesevelam is available in tablet form and as a powder for oral suspension formulation; the latter may be of benefit to elderly patients with swallowing difficulties. As

  1. A Systematic Investigation of Structure/Function Requirements for the Apolipoprotein A-I/Lecithin Cholesterol Acyltransferase Interaction Loop of High-density Lipoprotein.

    PubMed

    Gu, Xiaodong; Wu, Zhiping; Huang, Ying; Wagner, Matthew A; Baleanu-Gogonea, Camelia; Mehl, Ryan A; Buffa, Jennifer A; DiDonato, Anthony J; Hazen, Leah B; Fox, Paul L; Gogonea, Valentin; Parks, John S; DiDonato, Joseph A; Hazen, Stanley L

    2016-03-18

    The interaction of lecithin-cholesterol acyltransferase (LCAT) with apolipoprotein A-I (apoA-I) plays a critical role in high-density lipoprotein (HDL) maturation. We previously identified a highly solvent-exposed apoA-I loop domain (Leu(159)-Leu(170)) in nascent HDL, the so-called "solar flare" (SF) region, and proposed that it serves as an LCAT docking site (Wu, Z., Wagner, M. A., Zheng, L., Parks, J. S., Shy, J. M., 3rd, Smith, J. D., Gogonea, V., and Hazen, S. L. (2007) Nat. Struct. Mol. Biol. 14, 861-868). The stability and role of the SF domain of apoA-I in supporting HDL binding and activation of LCAT are debated. Here we show by site-directed mutagenesis that multiple residues within the SF region (Pro(165), Tyr(166), Ser(167), and Asp(168)) of apoA-I are critical for both LCAT binding to HDL and LCAT catalytic efficiency. The critical role for possible hydrogen bond interaction at apoA-I Tyr(166) was further supported using reconstituted HDL generated from apoA-I mutants (Tyr(166) → Glu or Asn), which showed preservation in both LCAT binding affinity and catalytic efficiency. Moreover, the in vivo functional significance of NO2-Tyr(166)-apoA-I, a specific post-translational modification on apoA-I that is abundant within human atherosclerotic plaque, was further investigated by using the recombinant protein generated from E. coli containing a mutated orthogonal tRNA synthetase/tRNACUA pair enabling site-specific insertion of the unnatural amino acid into apoA-I. NO2-Tyr(166)-apoA-I, after subcutaneous injection into hLCAT(Tg/Tg), apoA-I(-/-) mice, showed impaired LCAT activation in vivo, with significant reduction in HDL cholesteryl ester formation. The present results thus identify multiple structural features within the solvent-exposed SF region of apoA-I of nascent HDL essential for optimal LCAT binding and catalytic efficiency.

  2. The Predictive Role of Serum Triglyceride to High-Density Lipoprotein Cholesterol Ratio According to Renal Function in Patients with Acute Myocardial Infarction

    PubMed Central

    Woo, Jong Shin; Lee, Tae Won; Ihm, Chun Gyoo; Kim, Yang Gyoon; Moon, Joo Young; Lee, Sang Ho; Jeong, Myung Ho; Jeong, Kyung Hwan

    2016-01-01

    Objective A high serum triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio has been reported as an independent predictor for cardiovascular events in the general population. However, the prognostic value of this ratio in patients with renal dysfunction is unclear. We examined the association of the TG/HDL-C ratio with major adverse cardiovascular events (MACEs) according to renal function in patients with acute myocardial infarction (AMI). Method This study was based on the Korea Acute Myocardial Infarction Registry database. Of 13,897 patients who were diagnosed with AMI, the study population included the 7,016 patients with available TG/HDL-C ratio data. Patients were stratified into three groups according to their estimated glomerular filtration rate (eGFR), and the TG/HDL-C ratio was categorized into tertiles. We investigated 12-month MACEs, which included cardiac death, myocardial infarction, and repeated percutaneous coronary intervention or coronary artery bypass grafting. Results During the 12-month follow up period, 593 patients experienced MACEs. There was a significant association between the TG/HDL-C ratio and MACEs (p<0.001) in the entire study cohort. Having a TG/HDL-C ratio value in the highest tertile of TG/HDL-C ratio was an independent factor associated with increased risk of MACEs (hazard ratio [HR], 1.56; 95% confidence interval [CI], 1.26–1.93; p<0.001). Then we performed subgroup analyses according to renal function. In patients with normal renal function (eGFR ≥ 90 ml/min/1.73m2) and mild renal dysfunction (eGFR ≥ 60 to < 90ml/min/1.73m2), a higher TG/HDL-C ratio was significantly associated with increased risk of MACEs (HR, 1.64; 95% CI, 1.04–2.60; p = 0.035; and HR, 1.56; 95% CI, 1.14–2.12; p = 0.005, respectively). However, in patients with moderate renal dysfunction (eGFR < 60 ml/min/1.73m2), TG/HDL-C ratio lost its predictive value on the risk of MACEs (HR, 1.23; 95% CI, 0.82–1.83; p = 0.317). Conclusions In

  3. High-density lipoprotein-cholesterol levels and risk of cancer in HIV-infected subjects: Data from the ICONA Foundation Cohort.

    PubMed

    Squillace, Nicola; Galli, Laura; Bandera, Alessandra; Castagna, Antonella; Madeddu, Giordano; Caramello, Pietro; Antinori, Andrea; Cattelan, Annamaria; Maggiolo, Franco; Cingolani, Antonella; Gori, Andrea; Monforte, Antonella d'Arminio

    2016-09-01

    Investigation of the relationship between high-density lipoprotein-cholesterol (HDL-c) and the risk of developing cancer in a prospective cohort of human immunodeficiency virus (HIV)-infected patients.The Italian Cohort of Antiretroviral-naïve Patients Foundation Cohort is an Italian multicenter observational study recruiting HIV-positive patients while still antiretroviral treatment-naïve, regardless of the reason since 1997.Patients with at least 1 HDL-c value per year since enrollment and one such value before antiretroviral treatment initiation were included. HDL-c values were categorized as either low (<39 mg/dL in males or <49 mg/dL in females) or normal. Cancer diagnoses were classified as AIDS-defining malignancies (ADMs) or non-AIDS-defining malignancies (NADMs). Kaplan-Meier curves and Cox proportional-hazards regression models were used.Among 4897 patients (13,440 person-years of follow-up [PYFU]), 104 diagnoses of cancer were observed (56 ADMs, 48 NADMs) for an overall incidence rate of 7.7 (95% confidence interval [CI] 6.3-9.2) per 1000 PYFU.Low HDL-c values at enrollment were associated with higher risk both of cancer (crude hazard ratio [HR] 1.72, 95% CI 1.16-2.56, P = 0.007) and of NADM (crude HR 2.50, 95% CI 1.35-4.76, P = 0.003). Multivariate analysis showed that the risk of cancer diagnosis was higher in patients with low HDL-c values (adjusted HR [AHR] 1.87, 95% CI 1.18-2.95, P = 0.007) in older patients, those patients more recently enrolled, and in those with low current cluster of differentiation 4+ levels, and/or high current HIV-ribonucleic acid.The multivariate model confirmed an association between HDL-c (AHR 2.61, 95% CI 1.40-4.89, P = 0.003) and risk of NADM.Low HDL-c is an independent predictor of cancer in HIV-1-infected subjects. PMID:27603338

  4. A Systematic Investigation of Structure/Function Requirements for the Apolipoprotein A-I/Lecithin Cholesterol Acyltransferase Interaction Loop of High-density Lipoprotein.

    PubMed

    Gu, Xiaodong; Wu, Zhiping; Huang, Ying; Wagner, Matthew A; Baleanu-Gogonea, Camelia; Mehl, Ryan A; Buffa, Jennifer A; DiDonato, Anthony J; Hazen, Leah B; Fox, Paul L; Gogonea, Valentin; Parks, John S; DiDonato, Joseph A; Hazen, Stanley L

    2016-03-18

    The interaction of lecithin-cholesterol acyltransferase (LCAT) with apolipoprotein A-I (apoA-I) plays a critical role in high-density lipoprotein (HDL) maturation. We previously identified a highly solvent-exposed apoA-I loop domain (Leu(159)-Leu(170)) in nascent HDL, the so-called "solar flare" (SF) region, and proposed that it serves as an LCAT docking site (Wu, Z., Wagner, M. A., Zheng, L., Parks, J. S., Shy, J. M., 3rd, Smith, J. D., Gogonea, V., and Hazen, S. L. (2007) Nat. Struct. Mol. Biol. 14, 861-868). The stability and role of the SF domain of apoA-I in supporting HDL binding and activation of LCAT are debated. Here we show by site-directed mutagenesis that multiple residues within the SF region (Pro(165), Tyr(166), Ser(167), and Asp(168)) of apoA-I are critical for both LCAT binding to HDL and LCAT catalytic efficiency. The critical role for possible hydrogen bond interaction at apoA-I Tyr(166) was further supported using reconstituted HDL generated from apoA-I mutants (Tyr(166) → Glu or Asn), which showed preservation in both LCAT binding affinity and catalytic efficiency. Moreover, the in vivo functional significance of NO2-Tyr(166)-apoA-I, a specific post-translational modification on apoA-I that is abundant within human atherosclerotic plaque, was further investigated by using the recombinant protein generated from E. coli containing a mutated orthogonal tRNA synthetase/tRNACUA pair enabling site-specific insertion of the unnatural amino acid into apoA-I. NO2-Tyr(166)-apoA-I, after subcutaneous injection into hLCAT(Tg/Tg), apoA-I(-/-) mice, showed impaired LCAT activation in vivo, with significant reduction in HDL cholesteryl ester formation. The present results thus identify multiple structural features within the solvent-exposed SF region of apoA-I of nascent HDL essential for optimal LCAT binding and catalytic efficiency. PMID:26797122

  5. Lipoprotein lipase variants interact with polyunsaturated fatty acids to modulate obesity traits in Puerto Ricans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lipoprotein lipase (LPL) is a candidate gene for obesity based on its role in triglyceride hydrolysis and the partitioning of fatty acids towards storage or oxidation. Whether dietary fatty acids modify LPL associated obesity risk is unknown. We examined five single nucleotide polymorphisms (SNPs) (...

  6. Targeting cholesterol in a liquid-disordered environment by theonellamides modulates cell membrane order and cell shape.

    PubMed

    Arita, Yuko; Nishimura, Shinichi; Ishitsuka, Reiko; Kishimoto, Takuma; Ikenouchi, Junichi; Ishii, Kumiko; Umeda, Masato; Matsunaga, Shigeki; Kobayashi, Toshihide; Yoshida, Minoru

    2015-05-21

    Roles of lipids in the cell membrane are poorly understood. This is partially due to the lack of methodologies, for example, tool chemicals that bind to specific membrane lipids and modulate membrane function. Theonellamides (TNMs), marine sponge-derived peptides, recognize 3β-hydroxysterols in lipid membranes and induce major morphological changes in cultured mammalian cells through as yet unknown mechanisms. Here, we show that TNMs recognize cholesterol-containing liquid-disordered domains and induce phase separation in model lipid membranes. Modulation of membrane order was also observed in living cells following treatment with TNM-A, in which cells shrank considerably in a cholesterol-, cytoskeleton-, and energy-dependent manner. These findings present a previously unrecognized mode of action of membrane-targeting natural products. Meanwhile, we demonstrated the importance of membrane order, which is maintained by cholesterol, for proper cell morphogenesis.

  7. Background diet and fat type alters plasma lipoprotein response but not aortic cholesterol accumulation in F1B golden syrian hamsters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dietary modification alters plasma lipoprotein profiles and atherosclerotic lesion progression in humans and some animal models. Variability in response to diet induced atherosclerosis has been reported in hamsters. Assessed was the interaction between background diet composition and dietary fat typ...

  8. Naringin regulates cholesterol homeostasis and inhibits inflammation via modulating NF-κB and ERK signaling pathways in vitro.

    PubMed

    Liang, Jing; Wang, Changyuan; Peng, Jinyong; Li, Wenshuang; Jin, Yue; Liu, Qi; Meng, Qiang; Liu, Kexin; Sun, Huijun

    2016-02-01

    The main purpose of this study was to examine if naringin contributed to the regulation of cholesterol homeostasis and inflammatory cytokine expressions in cholesterol and 25-OH-cholesterol-treated HepG2 cells and TNF-α-treated HUVECs. The gene and protein expressions related to cholesterol homeostasis and inflammation were determined by quantitative real-time reverse transcription-polymerase chain reaction and Western blotting. We obtained the following results: (1) A concentration-dependent increase of LDLR and CYP7A1 expressions was observed, through activating expressions of SREBP2 and PPARy in HepG2 cells after exposure to naringin; (2) EL gene and protein expressions in HUVECs were inhibited by naringin; (3) the expressions of inflammatory factors such as CRP, TNF-α, ICAM-1 and VCAM-1 in HepG2 cells, ICAM-1 and VCAM-1 in HUVECs restrained by naringin were confirmed; (4) NF-κB and ERK1/2 activities were quenched by naringin. In summary, naringin might not only effectively reduce cholesterol levels by stimulating cholesterol metabolism but also inhibit inflammatory response through reducing inflammatory cytokine expressions. The effects of naringin were achieved via modulating NF-κB and ERK signaling pathways.

  9. Inhibition of angiogenesis by selective estrogen receptor modulators through blockade of cholesterol trafficking rather than estrogen receptor antagonism.

    PubMed

    Shim, Joong Sup; Li, Ruo-Jing; Lv, Junfang; Head, Sarah A; Yang, Eun Ju; Liu, Jun O

    2015-06-28

    Selective estrogen receptor modulators (SERM) including tamoxifen are known to inhibit angiogenesis. However, the underlying mechanism, which is independent of their action on the estrogen receptor (ER), has remained largely unknown. In the present study, we found that tamoxifen and other SERM inhibited cholesterol trafficking in endothelial cells, causing a hyper-accumulation of cholesterol in late endosomes/lysosomes. Inhibition of cholesterol trafficking by tamoxifen was accompanied by abnormal subcellular distribution of vascular endothelial growth factor receptor-2 (VEGFR2) and inhibition of the terminal glycosylation of the receptor. Tamoxifen also caused perinuclear positioning of lysosomes, which in turn trapped the mammalian target of rapamycin (mTOR) in the perinuclear region of endothelial cells. Abnormal distribution of VEGFR2 and mTOR and inhibition of VEGFR2 and mTOR activities by tamoxifen were significantly reversed by addition of cholesterol-cyclodextrin complex to the culture media of endothelial cells. Moreover, high concentrations of tamoxifen inhibited endothelial and breast cancer cell proliferation in a cholesterol-dependent, but ER-independent, manner. Together, these results unraveled a previously unrecognized mechanism of angiogenesis inhibition by tamoxifen and other SERM, implicating cholesterol trafficking as an attractive therapeutic target for cancer treatment.

  10. Androgen and FSH synergistically stimulate lipoprotein degradation and utilization by ovary granulosa cells

    SciTech Connect

    Schreiber, J.R.; Nakamura, K.; Schmit, V.; Weinstein, D.B.

    1984-01-01

    Androgen can directly modulate the induction of steroidogenic enzymes by FSH (follicle stimulating hormone) in ovary granulosa cells. In studies of its mechanism of action, the authors examined the androgen effect on granulosa cell interaction with lipoproteins, the physiologic source of cholesterol. After granulosa cells were cultured for 48 hours with and without androgen and/or FSH, the cells were incubated for 24 hours with /sup 125/I-lipoproteins (human high density lipoprotein (HDL), rat HDL, or human low density lipoprotein (LDL)). The media were then analyzed for lipoprotein protein coat degradation products (mainly /sup 125/I-monoiodotyrosine) and progestin (mainly 20 alpha-dihydroprogesterone (20 alpha-DHP)). In the absence of FSH and androgen, 2 X 10(5) granulosa cells degraded basal levels of all three lipoproteins, but produced no measurable 20 alpha-DHP. The addition of 10(-7) M androstenedione (A), testosterone (T), or 5 alpha-dihydrotestosterone (DHT) had no effect on lipoprotein protein degradation or 20 alpha-DHP production. FSH alone stimulated lipoprotein protein degradation by 50 to 300% while the addition of androgen synergistically augmented the FSH-stimulated 20 alpha-DHP production as well as protein coat degradation of all three lipoproteins. DHT and T were both effective, indicating that androgens themselves, and not estrogen products, were responsible for the effect on lipoprotein protein degradation and 20 alpha-DHP production.

  11. Dietary capsanthin, the main carotenoid in paprika (Capsicum annuum), alters plasma high-density lipoprotein-cholesterol levels and hepatic gene expression in rats.

    PubMed

    Aizawa, Koichi; Inakuma, Takahiro

    2009-12-01

    The effects of dietary capsanthin, the main carotenoid in paprika (Capsicum annuum), on lipid metabolism were examined. Young male Wistar rats were fed diets containing paprika powder, paprika organic solvent extract, residue of paprika extract, and purified capsanthin. Administration of purified capsanthin for 2 weeks resulted in a significant increase in plasma HDL-cholesterol (P < 0.05) without detectable differences in plasma total cholesterol and TAG concentrations. A statistically significant correlation (r 0.567; P < 0.001) was found between dietary capsanthin concentrations and plasma HDL-cholesterol concentrations. Animals receiving diets containing two different capsanthin concentrations exhibited dose-dependent increases in plasma HDL-cholesterol (r 0.597; P < 0.005). While capsanthin was absent in the liver of animals fed the basal diet, it increased markedly in capsanthin-fed animals (P < 0.001). Quantitative analyses of hepatic mRNA levels revealed that capsanthin administration resulted in up-regulation of mRNA for apoA5 and lecithin cholesterol acyltransferase (LCAT), without significant differences in other mRNA levels related to HDL-cholesterol metabolism. These results suggest that capsanthin had an HDL-cholesterol-raising effect on plasma, and the potential to increase cholesterol efflux to HDL particles by increasing apoA5 levels and/or enhancement of LCAT activity.

  12. Ellagic acid protects endothelial cells from oxidized low-density lipoprotein-induced apoptosis by modulating the PI3K/Akt/eNOS pathway

    SciTech Connect

    Ou, Hsiu-Chung; Lee, Wen-Jane; Lee, Shin-Da; Huang, Chih-Yang; Chiu, Tsan-Hung; Tsai, Kun-Ling; Hsu, Wen-Cheng; Sheu, Wayne Huey-Herng

    2010-10-15

    Endothelial apoptosis is a driving force in atherosclerosis development. Oxidized low-density lipoprotein (oxLDL) promotes inflammatory and thrombotic processes and is highly atherogenic, as it stimulates macrophage cholesterol accumulation and foam cell formation. Previous studies have shown that the phosphatidylinositol 3-kinase/Akt/endothelial nitric oxide synthase/nitric oxide (PI3K/Akt/eNOS/NO) pathway is involved in oxLDL-induced endothelial apoptosis. Ellagic acid, a natural polyphenol found in berries and nuts, has in recent years been the subject of intense research within the fields of cancer and inflammation. However, its protective effects against oxLDL-induced injury in vascular endothelial cells have not been clarified. In the present study, we investigated the anti-apoptotic effect of ellagic acid in human umbilical vein endothelial cells (HUVECs) exposed to oxLDL and explored the possible mechanisms. Our results showed that pretreatment with ellagic acid (5-20 {mu}M) significantly attenuated oxLDL-induced cytotoxicity, apoptotic features, and generation of reactive oxygen species (ROS). In addition, the anti-apoptotic effect of ellagic acid was partially inhibited by a PI3K inhibitor (wortmannin) and a specific eNOS inhibitor (cavtratin) but not by an ERK inhibitor (PD98059). In exploring the underlying mechanisms of ellagic acid action, we found that oxLDL decreased Akt and eNOS phosphorylation, which in turn activated NF-{kappa}B and downstream pro-apoptotic signaling events including calcium accumulation, destabilization of mitochondrial permeability, and disruption of the balance between pro- and anti-apoptotic Bcl-2 proteins. Those alterations induced by oxLDL, however, were attenuated by pretreatment with ellagic acid. The inhibition of oxLDL-induced endothelial apoptosis by ellagic acid is due at least in part to its anti-oxidant activity and its ability to modulate the PI3K/Akt/eNOS signaling pathway.

  13. Tanshinone IIA Modulates Low Density Lipoprotein Uptake via Down-Regulation of PCSK9 Gene Expression in HepG2 Cells

    PubMed Central

    Wu, Ming-Jiuan; Tai, Mi-Hsueh; Yen, Jui-Hung

    2016-01-01

    Tanshinone IIA, one of the most pharmacologically bioactive phytochemicals isolated from Salvia miltiorrhiza Bunge, possesses several biological activities such as anti-inflammation, anti-cancer, neuroprotection and hypolipidemic activities. In this study, we aim to investigate the hypocholesterolemic effect of tanshinone IIA in hepatic cells. We demonstrated that tanshinone IIA significantly increased the amount of low-density lipoprotein receptor (LDLR) and LDL uptake activity in HepG2 cells at the post-transcriptional regulation. We further demonstrated that tanshinone IIA inhibited the expression of proprotein convertase subtilisin/kexin type 9 (PCSK9) mRNA and mature protein, which may lead to an increase the cell-surface LDLR in hepatic cells. We further identified a regulatory DNA element involved in the tanshinone IIA-mediated PCSK9 down-regulation, which is located between the -411 and -336 positions of the PCSK9 promoter. Moreover, we found that tanshinone IIA markedly increased the nuclear forkhead box O3a (FoxO3a) level, enhanced FoxO3a/PCSK9 promoter complexes formation and decreased the PCSK9 promoter binding capacity of hepatocyte nuclear factor 1α (HNF-1α), resulting in suppression of PCSK9 gene expression. Finally, we found that the statin-induced PCSK9 overexpression was attenuated and the LDLR activity was elevated in a synergic manner by combination of tanshinone IIA treatment in HepG2 cells. Overall, our results reveal that the tanshinone IIA modulates LDLR level and activity via down-regulation of PCSK9 expression in hepatic cells. Our current findings provide a molecular basis of tanshinone IIA to develop PCSK9 inhibitors for cholesterol management. PMID:27617748

  14. Mitochondrion-Targeted Peptide SS-31 Inhibited Oxidized Low-Density Lipoproteins-Induced Foam Cell Formation through both ROS Scavenging and Inhibition of Cholesterol Influx in RAW264.7 Cells.

    PubMed

    Hao, Shuangying; Ji, Jiajie; Zhao, Hongting; Shang, Longcheng; Wu, Jing; Li, Huihui; Qiao, Tong; Li, Kuanyu

    2015-12-01

    Foam cell formation as a result of imbalance of modified cholesterol influx and efflux by macrophages is a key to the occurrence and development of atherosclerosis. Oxidative stress is thought to be involved in the pathogenesis of atherosclerosis. SS-31 is a member of the Szeto-Schiller (SS) peptides shown to specifically target the inner mitochondrial membrane to scavenge reactive oxygen species. In this study, we investigated whether SS-31 may provide protective effect on macrophage from foam cell formation in RAW264.7 cells. The results showed that SS-31 inhibited oxidized low-density lipoproteins (ox-LDL)-induced foam cell formation and cholesterol accumulation, demonstrated by intracellular oil red O staining and measurement of cholesterol content. The mechanism was revealed that SS-31 did not only significantly attenuated ox-LDL-induced generation of reactive oxygen species (ROS) and increased the activities of superoxide dismutases, but also dose-dependently inhibited the expression of CD36 and LOX-1, two scavenger receptors of ox-LDL, while the expression of ATP-binding cassette A1 and G1, playing a pivotal role in cholesterol efflux, was not affected. As a result, SS-31 decreased pro-inflammatory cytokines such as interleukin 6 and tumor necrosis factor alpha, suggesting the prevention of inflammatory responses. In conclusion, our results demonstrate that SS-31 provides a beneficial effect on macrophages from foam cell formation, likely, through both ROS scavenging and inhibition of cholesterol influx. Therefore, SS-31 may potentially be of therapeutic relevance in prevention of human atherogenesis.

  15. Mitochondrion-Targeted Peptide SS-31 Inhibited Oxidized Low-Density Lipoproteins-Induced Foam Cell Formation through both ROS Scavenging and Inhibition of Cholesterol Influx in RAW264.7 Cells.

    PubMed

    Hao, Shuangying; Ji, Jiajie; Zhao, Hongting; Shang, Longcheng; Wu, Jing; Li, Huihui; Qiao, Tong; Li, Kuanyu

    2015-01-01

    Foam cell formation as a result of imbalance of modified cholesterol influx and efflux by macrophages is a key to the occurrence and development of atherosclerosis. Oxidative stress is thought to be involved in the pathogenesis of atherosclerosis. SS-31 is a member of the Szeto-Schiller (SS) peptides shown to specifically target the inner mitochondrial membrane to scavenge reactive oxygen species. In this study, we investigated whether SS-31 may provide protective effect on macrophage from foam cell formation in RAW264.7 cells. The results showed that SS-31 inhibited oxidized low-density lipoproteins (ox-LDL)-induced foam cell formation and cholesterol accumulation, demonstrated by intracellular oil red O staining and measurement of cholesterol content. The mechanism was revealed that SS-31 did not only significantly attenuated ox-LDL-induced generation of reactive oxygen species (ROS) and increased the activities of superoxide dismutases, but also dose-dependently inhibited the expression of CD36 and LOX-1, two scavenger receptors of ox-LDL, while the expression of ATP-binding cassette A1 and G1, playing a pivotal role in cholesterol efflux, was not affected. As a result, SS-31 decreased pro-inflammatory cytokines such as interleukin 6 and tumor necrosis factor alpha, suggesting the prevention of inflammatory responses. In conclusion, our results demonstrate that SS-31 provides a beneficial effect on macrophages from foam cell formation, likely, through both ROS scavenging and inhibition of cholesterol influx. Therefore, SS-31 may potentially be of therapeutic relevance in prevention of human atherogenesis. PMID:26633327

  16. The V227A polymorphism at the PPARA locus is associated with serum lipid concentrations and modulates the association between dietary polyunsaturated fatty acid intake and serum high density lipoprotein concentrations in Chinese women.

    PubMed

    Chan, Edmund; Tan, Chuen Seng; Deurenberg-Yap, Mabel; Chia, Kee Seng; Chew, Suok Kai; Tai, E Shyong

    2006-08-01

    Peroxisome proliferators activated receptor alpha (PPARalpha) regulates the transcription of several proteins involved in human lipoprotein metabolism. We screened the PPARA locus for polymorphisms in 20 unrelated subjects from each of three ethnic groups (Chinese, Malays and Asian Indians). Only the V227A polymorphism was observed. We genotyped 4248 subjects (2899 Chinese, 761 Malay and 588 Asian Indians) and found allele frequencies for the A227 allele of 0.04 in Chinese, 0.006 in Malays and 0.003 in Asian Indians. We examined the associations between this polymorphism and serum lipid concentrations in Chinese. In women, but not in men, the presence of the A227 allele was associated with lower serum concentrations of total cholesterol [5.38mmol/l (95%CI: 5.22-5.54) versus 5.21mmol/l (95%CI: 4.99-5.43), p=0.047] and triglycerides [1.19mmol/l (95%CI: 1.10-1.28) versus 1.09mmol/l (95%CI: 0.98-1.21), p=0.048]. We also found that the V227A polymorphism modulates the association between dietary polyunsaturated fatty acid intake and serum high density lipoprotein concentration (p-value for interaction=0.049). Our findings implicate PPARalpha in the lipid lowering associated with diets high in PUFA and suggests that genetic variation at the PPARA locus may determine the lipid response to changes in PUFA intake. PMID:16288935

  17. A cholesterol-binding domain in STIM1 modulates STIM1-Orai1 physical and functional interactions

    PubMed Central

    Pacheco, Jonathan; Dominguez, Laura; Bohórquez-Hernández, A.; Asanov, Alexander; Vaca, Luis

    2016-01-01

    STIM1 and Orai1 are the main components of a widely conserved Calcium influx pathway known as store-operated calcium entry (SOCE). STIM1 is a calcium sensor, which oligomerizes and activates Orai channels when calcium levels drop inside the endoplasmic reticulum (ER). The series of molecular rearrangements that STIM1 undergoes until final activation of Orai1 require the direct exposure of the STIM1 domain known as SOAR (Stim Orai Activating Region). In addition to these complex molecular rearrangements, other constituents like lipids at the plasma membrane, play critical roles orchestrating SOCE. PI(4,5)P2 and enriched cholesterol microdomains have been shown as important signaling platforms that recruit the SOCE machinery in steps previous to Orai1 activation. However, little is known about the molecular role of cholesterol once SOCE is activated. In this study we provide clear evidence that STIM1 has a cholesterol-binding domain located inside the SOAR region and modulates Orai1 channels. We demonstrate a functional association of STIM1 and SOAR to cholesterol, indicating a close proximity of SOAR to the inner layer of the plasma membrane. In contrast, the depletion of cholesterol induces the SOAR detachment from the plasma membrane and enhances its association to Orai1. These results are recapitulated with full length STIM1. PMID:27459950

  18. Macrophage lipoprotein lipase modulates the development of atherosclerosis but not adiposity

    PubMed Central

    Takahashi, Manabu; Yagyu, Hiroaki; Tazoe, Fumiko; Nagashima, Shuichi; Ohshiro, Taichi; Okada, Kenta; Osuga, Jun-ichi; Goldberg, Ira J.; Ishibashi, Shun

    2013-01-01

    The role of macrophage lipoprotein lipase (LpL) in the development of atherosclerosis and adiposity was examined in macrophage LpL knockout (MLpLKO) mice. MLpLKO mice were generated using cre-loxP gene targeting. Loss of LpL in macrophages did not alter plasma LpL activity or lipoprotein levels. Incubation of apolipoprotein E (ApoE)-deficient β-VLDL with peritoneal macrophages from ApoE knockout mice lacking macrophage LpL (MLpLKO/ApoEKO) led to less cholesteryl ester formation than that found with ApoEKO macrophages. MLpLKO/ApoEKO macrophages had reduced intracellular triglyceride levels, with decreased CD36 and carnitine palmitoyltransferase-1 mRNA levels compared with ApoEKO macrophages, when incubated with VLDL. Although both MLpLKO/ApoEKO and ApoEKO mice developed comparable hypercholesterolemia in response to feeding with a Western-type diet for 12 weeks, atherosclerosis was less in MLpLKO/ApoEKO mice. Epididymal fat mass and gene expression levels associated with inflammation did not differ between the two groups. In conclusion, macrophage LpL plays an important role in the development of atherosclerosis but not adiposity. PMID:23378601

  19. Cholesterol modulation of the expression of mitochondrial aconitase in human prostatic carcinoma cells.

    PubMed

    Feng, Tsui-Hsia; Tsui, Ke-Hung; Juang, Horng-Heng

    2005-06-30

    Mitochondrial aconitase (mACON) is the key enzyme for the citrate oxidation in the mitochondrial Krebs cycle. Cholesterol treatment (10 microg/ml of cholesterol and 1 microg/ml of 25-hydroxycholesterol) for 24 h stimulates mACON enzymatic activity in human prostatic carcinoma cells (PC-3) and hepatoma cells (HepG2). Mevastatin, a cholesterol synthesis antagonist, blocked the effect of cholesterol treatment on mACON. The cholesterol treatment stimulated mACON enzymatic activity, which enhanced the citrate utility but decreased intracellular ATP levels in PC-3 cells. The immunoblotting and transient gene expression assays demonstrated that cholesterol treatment enhances the gene expression of mACON. Mutation of the putative sterol response element (SRE) from GACGCCCCACT to GACGCCCATAT abolished the stimulating effects of cholesterol on the promoter activity of mACON gene. The results suggest that cholesterol treatment induces the mACON gene expression through the SRE signal transduction pathway. Our study demonstrated the deregulation of cholesterol on the citrate metabolism. PMID:16201454

  20. Ciprofibrate therapy in patients with hypertriglyceridemia and low high density lipoprotein (HDL)-cholesterol: greater reduction of non-HDL cholesterol in subjects with excess body weight (The CIPROAMLAT study)

    PubMed Central

    Aguilar-Salinas, Carlos A; Assis-Luores-Vale, Andréia; Stockins, Benjamín; Rengifo, Hector Mario; Filho, José Dondici; Neto, Abrahão Afiune; Rabelo, Lísia Marcílio; Torres, Kerginaldo Paulo; Oliveira, José Egídio Paulo de; Machado, Carlos Alberto; Reyes, Eliana; Saavedra, Victor; Florenzano, Fernando; Hernández, Ma Victoria; Jiménez, Sergio Hernandez; Ramírez, Erika; Vazquez, Cuauhtémoc; Salinas, Saul; Hernández, Ismael; Medel, Octavio; Moreno, Ricardo; Lugo, Paula; Alvarado, Ricardo; Mehta, Roopa; Gutierrez, Victor; Gómez Pérez, Francisco J

    2004-01-01

    Background Hypertriglyceridemia in combination with low HDL cholesterol levels is a risk factor for cardiovascular disease. Our objective was to evaluate the efficacy of ciprofibrate for the treatment of this form of dyslipidemia and to identify factors associated with better treatment response. Methods Multicenter, international, open-label study. Four hundred and thirty seven patients were included. The plasma lipid levels at inclusion were fasting triglyceride concentrations between 1.6–3.9 mM/l and HDL cholesterol ≤ 1.05 mM/l for women and ≤ 0.9 mM/l for men. The LDL cholesterol was below 4.2 mM/l. All patients received ciprofibrate 100 mg/d. Efficacy and safety parameters were assessed at baseline and at the end of the treatment. The primary efficacy parameter of the study was percentage change in triglycerides from baseline. Results After 4 months, plasma triglyceride concentrations were decreased by 44% (p < 0.001). HDL cholesterol concentrations were increased by 10% (p < 0.001). Non-HDL cholesterol was decreased by 19%. A greater HDL cholesterol response was observed in lean patients (body mass index < 25 kg/m2) compared to the rest of the population (8.2 vs 19.7%, p < 0.001). In contrast, cases with excess body weight had a larger decrease in non-HDL cholesterol levels (-20.8 vs -10.8%, p < 0.001). There were no significant complications resulting from treatment with ciprofibrate. Conclusions Ciprofibrate is efficacious for the correction of hypertriglyceridemia / low HDL cholesterol. A greater decrease in non-HDL cholesterol was found among cases with excess body weight. The mechanism of action of ciprofibrate may be influenced by the pathophysiology of the disorder being treated. PMID:15272932

  1. KIF6, LPA, TAS2R50, and VAMP8 genetic variation, low density lipoprotein cholesterol lowering response to pravastatin, and heart disease risk reduction in the elderly

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Single nucleotide polymorphisms (SNPs) at the KIF6 (kinesin like protein 6, rs20455 or 719Arg), LPA (lipoprotein(a), rs3798220), TAS2R50 (taste receptor type 2, member 50, rs1376251) and VAMP8 (vesicle-associated membrane protein 8, rs1010) have previously been associated with low density lipoprotei...

  2. Membrane Cholesterol Regulates Lysosome-Plasma Membrane Fusion Events and Modulates Trypanosoma cruzi Invasion of Host Cells

    PubMed Central

    Hissa, Bárbara; Duarte, Jacqueline G.; Kelles, Ludmila F.; Santos, Fabio P.; del Puerto, Helen L.; Gazzinelli-Guimarães, Pedro H.; de Paula, Ana M.; Agero, Ubirajara; Mesquita, Oscar N.; Guatimosim, Cristina; Chiari, Egler; Andrade, Luciana O.

    2012-01-01

    available in the cell and that cholesterol depletion may modulate the fusion of pre-docked lysosomes at the cell cortex. PMID:22479662

  3. Understanding Cholesterol and Heart Health | NIH MedlinePlus the Magazine

    MedlinePlus

    ... cholesterol throughout the body: Low-density lipoproteins (LDL): LDL cholesterol sometimes is called "bad" cholesterol. A high LDL ... or even death. The higher the level of LDL cholesterol in your blood, the GREATER your chance is ...

  4. Facts about...Blood Cholesterol. Revised.

    ERIC Educational Resources Information Center

    National Heart, Lung, and Blood Inst. (DHHS/NIH), Bethesda, MD.

    This fact sheet on blood cholesterol examines the connection between cholesterol and heart disease, lists risk factors for heart disease that can and cannot be controlled, points out who can benefit from lowering blood cholesterol, distinguishes between blood and dietary cholesterol, describes low density lipoprotein and high density lipoprotein…

  5. Enhancement of High-Density Lipoprotein Cholesterol Functions by Encapsulation of Policosanol Exerts Anti-Senescence and Tissue Regeneration Effects Via Improvement of Anti-Glycation, Anti-Apoptosis, and Cholesteryl Ester Transfer Inhibition.

    PubMed

    Lim, So-Mang; Yoo, Jeong-Ah; Lee, Eun-Young; Cho, Kyung-Hyun

    2016-02-01

    Consumption of policosanol (PCO), a refined mixture of sugar cane wax alcohols, can elevate serum levels of high-density lipoprotein cholesterol (HDL-C), although the molecular mechanism is still unknown. To investigate the mechanism of action responsible for the anti-senescence effects of PCO on lipoprotein metabolism and HDL functionality, we synthesized reconstituted HDL (rHDL) containing PCO. Encapsulation of PCO by rHDL (PCO-rHDL) enhanced anti-oxidant activity against cupric ion-mediated low-density lipoprotein (LDL) oxidation. PCO-rHDL (final concentration, 9 μM PCO) showed more potent anti-oxidant activity than vitamin C treatment (final concentration, 100 μM). PCO-rHDL inhibited fructose-mediated glycation, which is a major pathological mechanism of diabetic complications, in a dose-dependent manner. PCO also showed cytoprotective effects in monocytes and macrophages with less triggering of apoptotic processes and reactive oxygen species (ROS) production in the presence of hydrogen peroxide (H2O2). PCO-rHDL strongly inhibited uptake of acetylated LDL into macrophages, which is an initial atherosclerotic process. Surprisingly, PCO-rHDL inhibited human serum cholesteryl ester transfer protein (CETP) activity by up to 47% (final concentration, 10 μM PCO). Subcutaneous injection of PCO-rHDL dose-dependently enhanced tissue regeneration activity by 2.4-fold and 3.6-fold compared to that of the phosphate-buffered saline (PBS) control. In conclusion, PCO in HDL showed potent anti-oxidant, anti-glycation, and CETP inhibitory activities along with tissue regenerative activity, especially upon incorporation into HDL. These results suggest that PCO can enhance functionality of HDL in serum to exert anti-senescence and longevity effects.

  6. Enhancement of High-Density Lipoprotein Cholesterol Functions by Encapsulation of Policosanol Exerts Anti-Senescence and Tissue Regeneration Effects Via Improvement of Anti-Glycation, Anti-Apoptosis, and Cholesteryl Ester Transfer Inhibition.

    PubMed

    Lim, So-Mang; Yoo, Jeong-Ah; Lee, Eun-Young; Cho, Kyung-Hyun

    2016-02-01

    Consumption of policosanol (PCO), a refined mixture of sugar cane wax alcohols, can elevate serum levels of high-density lipoprotein cholesterol (HDL-C), although the molecular mechanism is still unknown. To investigate the mechanism of action responsible for the anti-senescence effects of PCO on lipoprotein metabolism and HDL functionality, we synthesized reconstituted HDL (rHDL) containing PCO. Encapsulation of PCO by rHDL (PCO-rHDL) enhanced anti-oxidant activity against cupric ion-mediated low-density lipoprotein (LDL) oxidation. PCO-rHDL (final concentration, 9 μM PCO) showed more potent anti-oxidant activity than vitamin C treatment (final concentration, 100 μM). PCO-rHDL inhibited fructose-mediated glycation, which is a major pathological mechanism of diabetic complications, in a dose-dependent manner. PCO also showed cytoprotective effects in monocytes and macrophages with less triggering of apoptotic processes and reactive oxygen species (ROS) production in the presence of hydrogen peroxide (H2O2). PCO-rHDL strongly inhibited uptake of acetylated LDL into macrophages, which is an initial atherosclerotic process. Surprisingly, PCO-rHDL inhibited human serum cholesteryl ester transfer protein (CETP) activity by up to 47% (final concentration, 10 μM PCO). Subcutaneous injection of PCO-rHDL dose-dependently enhanced tissue regeneration activity by 2.4-fold and 3.6-fold compared to that of the phosphate-buffered saline (PBS) control. In conclusion, PCO in HDL showed potent anti-oxidant, anti-glycation, and CETP inhibitory activities along with tissue regenerative activity, especially upon incorporation into HDL. These results suggest that PCO can enhance functionality of HDL in serum to exert anti-senescence and longevity effects. PMID:26161621

  7. The Liver Clock Controls Cholesterol Homeostasis through Trib1 Protein-mediated Regulation of PCSK9/Low Density Lipoprotein Receptor (LDLR) Axis.

    PubMed

    Ma, Di; Liu, Tongyu; Chang, Lin; Rui, Crystal; Xiao, Yuanyuan; Li, Siming; Hogenesch, John B; Chen, Y Eugene; Lin, Jiandie D

    2015-12-25

    Disruption of the body clock has been recognized as a risk factor for cardiovascular disease. How the circadian pacemaker interacts with the genetic factors associated with plasma lipid traits remains poorly understood. Recent genome-wide association studies have identified an expanding list of genetic variants that influence plasma cholesterol and triglyceride levels. Here we analyzed circadian regulation of lipid-associated candidate genes in the liver and identified two distinct groups exhibiting rhythmic and non-rhythmic patterns of expression during light-dark cycles. Liver-specific inactivation of Bmal1 led to elevated plasma LDL/VLDL cholesterol levels as a consequence of the disruption of the PCSK9/LDL receptor regulatory axis. Ablation of the liver clock perturbed diurnal regulation of lipid-associated genes in the liver and markedly reduced the expression of the non-rhythmically expressed gene Trib1. Adenovirus-mediated rescue of Trib1 expression lowered plasma PCSK9 levels, increased LDL receptor protein expression, and restored plasma cholesterol homeostasis in mice lacking a functional liver clock. These results illustrate an unexpected mechanism through which the biological clock regulates cholesterol homeostasis through its regulation of non-rhythmic genes in the liver.

  8. Free cholesterol is a potent regulator of lipid transfer protein function

    SciTech Connect

    Morton, R.E.

    1988-09-05

    This study investigates the effect of altered lipoprotein free cholesterol (FC) content on the transfer of cholesteryl ester (CE) and triglyceride (TG) from very low- (VLDL), low- (LDL), and high-(HDL) density lipoproteins by the plasma-derived lipid transfer protein (LTP). The FC content of VLDL and HDL was selectively altered by incubating these lipoproteins with FC/phospholipid dispersions of varying composition. FC-modified lipoproteins were then equilibrated with (3H) TG, (14C)CE-labeled lipoproteins of another class to facilitate the subsequent modification of the radiolabeled donor lipoproteins. LTP was added and the extent of radiolabeled TG and CE transfer determined after 1 h. With either LDL or VLDL as lipid donor, an increase in the FC content of these lipoproteins caused a concentration-dependent inhibition (up to 50%) of CE transfer from these particles, without any significant effect on TG transfer. In contrast, with HDL as donor, increasing the HDL FC content had little effect on CE transfer from HDL, but markedly stimulated (up to 2.5-fold) the transfer of TG. This differential effect of FC on the unidirectional transfer of radiolabeled lipids from VLDL and HDL led to marked effects on LTP-facilitated net mass transfer of lipids. During long-term incubation of a constant amount of LTP with FC-modified VLDL and HDL, the extent of net mass transfer was linearly related to lipoprotein FC content; a 4-fold increase in FC content resulted in a 3-fold stimulation of the CE mass transferred to VLDL, which was coupled to an equimolar, reciprocal transfer of TG mass to HDL. Since lipid transfer between lipoproteins is integral to the process of reverse cholesterol transport, we conclude that lipoprotein FC levels are a potent, positive regulator of the pathways involved in sterol clearance. FC may modulate lipid transfer by altering the availability of CE and TG to LTP at the lipoprotein surface.

  9. Atherosclerosis, diabetes and lipoproteins.

    PubMed

    Tomkin, Gerald H

    2010-07-01

    The enormous burden of vascular disease is likely to expand rapidly as sedentary obesity and diabetes increase. Although cholesterol plays a major role in atherosclerosis and LDL is the major carrier of cholesterol in the blood, the importance of the postprandial triglyceride-rich lipoproteins in the development of atherosclerosis is gaining recognition. The role of HDL-cholesterol is also receiving more attention. These changes have been forced upon us by the realization that statins, which primarily lower LDL-cholesterol, only reduce the risk of atherosclerosis by 30%, suggesting that 70% of the risk still has to be explained and treated. In diabetes, abnormality in the metabolism of the triglyceride-rich lipoproteins and the inter-relationship with HDL-cholesterol appears to be of primary importance in atherosclerotic risk. Postprandial studies are difficult to carry out, which is one reason why large studies have not so far been performed. The important new findings in chylomicron metabolism suggest new treatments for the future.

  10. Effects of fenofibrate on lipid profiles, cholesterol ester transfer activity, and in-stent intimal hyperplasia in patients after elective coronary stenting

    PubMed Central

    2010-01-01

    Background The association between modulation of detailed lipoprotein profiles and cholesterol ester transfer (CET) activity by peroxisome proliferator-activated receptor (PPAR)-a agonists in patients with coronary artery disease remains unclear. We assessed lipid profiles, plasma CET activity, and in-stent intimal hyperplasia after fenofibrate treatment in patients who underwent elective coronary stenting. Methods Forty-three consecutive patients who underwent elective coronary stenting were randomized to the fenofibrate group (300 mg/day for 25 weeks, n = 22) or the control group (n = 21). At baseline and follow up, CET activity and lipoprotein profiles were measured, and quantitative coronary angiography was performed. Results In the fenofibrate group, the levels of large very low-density lipoprotein cholesterol, and small low-density lipoprotein (LDL) cholesterol decreased and those of small high-density lipoprotein (HDL) cholesterol increased. Besides, CET activity decreased independent of the effect of fenofibrate on total and LDL cholesterol. The reduction of CET activity significantly correlated with the increase in LDL particle size (r = 0.47, P = 0.03) and the decrease of triglycerides in large HDL subclasses (r = 0.48, P = 0.03). Although there were no significant differences in restenosis parameters between the two groups, low CET activity significantly correlated with the inhibition of neointimal hyperplasia (r = 0.56, P = 0.01). Conclusions Fenofibrate inhibited CET activity and thereby improved atherogenic lipoprotein profiles, and reduced intimal hyperplasia after coronary stenting. PMID:20973966

  11. Cholesterol Modulates CFTR Confinement in the Plasma Membrane of Primary Epithelial Cells

    PubMed Central

    Abu-Arish, Asmahan; Pandzic, Elvis; Goepp, Julie; Matthes, Elizabeth; Hanrahan, John W.; Wiseman, Paul W.

    2015-01-01

    The cystic fibrosis transmembrane conductance regulator (CFTR) is a plasma-membrane anion channel that, when mutated, causes the disease cystic fibrosis. Although CFTR has been detected in a detergent-resistant membrane fraction prepared from airway epithelial cells, suggesting that it may partition into cholesterol-rich membrane microdomains (lipid rafts), its compartmentalization has not been demonstrated in intact cells and the influence of microdomains on CFTR lateral mobility is unknown. We used live-cell imaging, spatial image correlation spectroscopy, and k-space image correlation spectroscopy to examine the aggregation state of CFTR and its dynamics both within and outside microdomains in the plasma membrane of primary human bronchial epithelial cells. These studies were also performed during treatments that augment or deplete membrane cholesterol. We found two populations of CFTR molecules that were distinguishable based on their dynamics at the cell surface. One population showed confinement and had slow dynamics that were highly cholesterol dependent. The other, more abundant population was less confined and diffused more rapidly. Treatments that deplete the membrane of cholesterol caused the confined fraction and average number of CFTR molecules per cluster to decrease. Elevating cholesterol had the opposite effect, increasing channel aggregation and the fraction of channels displaying confinement, consistent with CFTR recruitment into cholesterol-rich microdomains with dimensions below the optical resolution limit. Viral infection caused the nanoscale microdomains to fuse into large platforms and reduced CFTR mobility. To our knowledge, these results provide the first biophysical evidence for multiple CFTR populations and have implications for regulation of their surface expression and channel function. PMID:26153705

  12. The molecular-scale arrangement and mechanical strength of phospholipid/cholesterol mixed bilayers investigated by frequency modulation atomic force microscopy in liquid

    NASA Astrophysics Data System (ADS)

    Asakawa, Hitoshi; Fukuma, Takeshi

    2009-07-01

    Cholesterols play key roles in controlling molecular fluidity in a biological membrane, yet little is known about their molecular-scale arrangements in real space. In this study, we have directly imaged lipid-cholesterol complexes in a model biological membrane consisting of dipalmitoylphosphatidylcholine (DPPC) and cholesterols by frequency modulation atomic force microscopy (FM-AFM) in phosphate buffer solution. FM-AFM images of a DPPC/cholesterol bilayer in the liquid-ordered phase showed higher energy dissipation values compared to those measured on a nanoscale DPPC domain in the gel phase, reflecting the increased molecular fluidity due to the insertion of cholesterols. Molecular-resolution FM-AFM images of a DPPC/cholesterol bilayer revealed the existence of a rhombic molecular arrangement (lattice constants: a = 0.46 nm, b = 0.71 nm) consisting of alternating rows of DPPC and cholesterols as well as the increased defect density and reduced molecular ordering. The mechanical strength of a DPPC/cholesterol bilayer was quantitatively evaluated by measuring a loading force required to penetrate the membrane with an AFM tip. The result revealed the significant decrease of mechanical strength upon insertion of cholesterols. Based on the molecular-scale arrangement found in this study, we propose a model to explain the reduced mechanical strength in relation to the formation of lipid-ion networks.

  13. Gonadotropin-releasing hormone modulates cholesterol synthesis and steroidogenesis in SH-SY5Y cells.

    PubMed

    Rosati, Fabiana; Sturli, Niccolò; Cungi, Maria Chiara; Morello, Matteo; Villanelli, Fabio; Bartolucci, Gianluca; Finocchi, Claudia; Peri, Alessandro; Serio, Mario; Danza, Giovanna

    2011-04-01

    Neurosteroids are involved in Central Nervous System development, brain functionality and neuroprotection but little is known about regulators of their biosynthesis. Recently gonadotropins, Gonadotropin-releasing Hormone (GnRH) and their receptors have been localized in different brain regions, such as hippocampus and cortex. Using human neuronal-like cells we found that GnRH up-regulates the expression of key genes of cholesterol and steroid synthesis when used in a narrow range around 1.0 nM. The expression of Hydroxysterol D24-reductase (seladin-1/DHCR24), that catalyzes the last step of cholesterol biosynthesis, is increased by 50% after 90 min of incubation with GnRH. StAR protein and P450 side chain cleavage (P450scc) are up-regulated by 3.3 times after 90 min and by 3.5 times after 3 h, respectively. GnRH action is mediated by LH and 1.0 nM GnRH enhances the expression of LHβ as well. A two fold increase of cell cholesterol is induced after 90 min of GnRH incubation and 17β-estradiol (E2) production is increased after 24, 48 and 72 h. These data indicate for the first time that GnRH regulates both cholesterol and steroid biosynthesis in human neuronal-like cells and suggest a new physiological role for GnRH in the brain. PMID:21296663

  14. A frameshift mutation in the human apolipoprotein A-I gene causes high density lipoprotein deficiency, partial lecithin: cholesterol-acyltransferase deficiency, and corneal opacities.

    PubMed Central

    Funke, H; von Eckardstein, A; Pritchard, P H; Karas, M; Albers, J J; Assmann, G

    1991-01-01

    Epidemiologic data of recent years have identified an important role of HDL deficiency in the etiology of atherosclerosis. Biochemical data suggest that some of these deficiencies may be a consequence of defects in the structural genes of HDL apolipoproteins or of plasma enzymes that modify HDL. We analyzed the genetic defect in a 42-yr-old patient suffering from corneal opacities and complete absence of HDL cholesterol but not of coronary artery disease, thus clinically resembling fish eye disease. The observation of an abnormal immunoblot banding pattern of apolipoprotein A-I (apo A-I) and of reduced lecithin: cholesterol acyltransferase (LCAT) activity in plasma led to sequence analysis of the genes for apo A-I and LCAT in this patient and his family. Direct sequencing of polymerase chain reaction amplified DNA segments containing the exons of the candidate genes, resulted in the identification of a frameshift mutation in apo A-I while the LCAT sequence was identical to the wild type. The apo A-I mutation was predictive for an extensive alteration of the COOH-terminal sequence of the encoded protein. Evidence for the release of this mutant protein into the plasma compartment and for the absence of normal apo A-I was derived from ultraviolet laser desorption/ionization mass spectrometry analysis. Our results suggest that a defective apo A-I is the causative defect in this case of HDL deficiency with corneal opacities. Images PMID:1898657

  15. Treadmill Exercise Training Modulates Hepatic Cholesterol Metabolism and Circulating PCSK9 Concentration in High-Fat-Fed Mice

    PubMed Central

    Jadhav, Kavita S.; Williamson, David L.; Rideout, Todd C.

    2013-01-01

    Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a novel biomarker of LDL clearance and a therapeutic target of cardiovascular disease. We examined the effects of aerobic exercise training in modulating PCSK9 abundance and hepatic sterol regulation in high-fat-fed C57BL/6 mice. Mice (n = 8) were assigned to a low-fat (LF), high-fat (HF), or an HF with exercise (HF + EX) group for 8 weeks. The HF + EX group was progressively trained 5 days/week on a motorized treadmill. The HF + EX group was protected against body weight (BW) gain and diet-induced dyslipidemia compared with the HF group. The HF + EX group demonstrated an increase in hepatic PCSK9 mRNA (1.9-fold of HF control, P < 0.05) and a reduction in plasma PCSK9 (14%) compared with the HF group. Compared with HF mice, HF + EX mice demonstrated reduced hepatic cholesterol (14%) and increased (P < 0.05) nuclear SREBP2 protein (1.8-fold of HF group) and LDLr mRNA (1.4-fold of HF group). Plasma PCSK9 concentrations correlated positively with plasma non-HDL-C (P = 0.01, r = 0.84). Results suggest that treadmill exercise reduces non-HDL cholesterol and differentially modulates hepatic and blood PCSK9 abundance in HF-fed C57BL/6 mice. PMID:23862065

  16. Validation of the Martin Method for Estimating Low-Density Lipoprotein Cholesterol Levels in Korean Adults: Findings from the Korea National Health and Nutrition Examination Survey, 2009-2011.

    PubMed

    Lee, Jongseok; Jang, Sungok; Son, Heejeong

    2016-01-01

    Despite the importance of accurate assessment for low-density lipoprotein cholesterol (LDL-C), the Friedewald formula has primarily been used as a cost-effective method to estimate LDL-C when triglycerides are less than 400 mg/dL. In a recent study, an alternative to the formula was proposed to improve estimation of LDL-C. We evaluated the performance of the novel method versus the Friedewald formula using a sample of 5,642 Korean adults with LDL-C measured by an enzymatic homogeneous assay (LDL-CD). Friedewald LDL-C (LDL-CF) was estimated using a fixed factor of 5 for the ratio of triglycerides to very-low-density lipoprotein cholesterol (TG:VLDL-C ratio). However, the novel LDL-C (LDL-CN) estimates were calculated using the N-strata-specific median TG:VLDL-C ratios, LDL-C5 and LDL-C25 from respective ratios derived from our data set, and LDL-C180 from the 180-cell table reported by the original study. Compared with LDL-CF, each LDL-CN estimate exhibited a significantly higher overall concordance in the NCEP-ATP III guideline classification with LDL-CD (p< 0.001 for each comparison). Overall concordance was 78.2% for LDL-CF, 81.6% for LDL-C5, 82.3% for LDL-C25, and 82.0% for LDL-C180. Compared to LDL-C5, LDL-C25 significantly but slightly improved overall concordance (p = 0.008). LDL-C25 and LDL-C180 provided almost the same overall concordance; however, LDL-C180 achieved superior improvement in classifying LDL-C < 70 mg/dL compared to the other estimates. In subjects with triglycerides of 200 to 399 mg/dL, each LDL-CN estimate showed a significantly higher concordance than that of LDL-CF (p< 0.001 for each comparison). The novel method offers a significant improvement in LDL-C estimation when compared with the Friedewald formula. However, it requires further modification and validation considering the racial differences as well as the specific character of the applied measuring method. PMID:26824910

  17. Comparison of effectiveness of rosuvastatin versus atorvastatin on the achievement of combined C-reactive protein (<2 mg/L) and low-density lipoprotein cholesterol (< 70 mg/dl) targets in patients with type 2 diabetes mellitus (from the ANDROMEDA study).

    PubMed

    Betteridge, D John; Gibson, J Martin; Sager, Philip T

    2007-10-15

    Decreasing C-reactive protein (CRP) in addition to decreasing low-density lipoprotein (LDL) cholesterol may further decrease coronary heart disease risk. The effects of rosuvastatin compared with atorvastatin in achieving a combined target of LDL cholesterol <70 mg/dl and CRP <2 mg/L in 509 patients with type 2 diabetes mellitus was evaluated. CRP decreased significantly versus baseline in both treatment groups. Significantly more patients treated with rosuvastatin achieved the combined end point of LDL cholesterol <70 mg/dl and CRP <2 mg/L compared with atorvastatin by the end of the study period (58% vs 37%; p <0.001 vs atorvastatin). In conclusion, CRP was effectively decreased in patients with type 2 diabetes receiving rosuvastatin or atorvastatin, whereas rosuvastatin decreased LDL cholesterol significantly more than atorvastatin.

  18. Modulation of glycosylation by. cap alpha. -d-tocopherol delivered to hepatoma cell line via human lipoproteins versus bovine serum

    SciTech Connect

    Yogeeswaran, G.; Triau, J.E.; Koul, O.

    1987-05-01

    Vitamin E (E) has been shown to cause a generalized reduction in the metabolism and cell surface expression of glycoconjugates (GC) in K3T3 cells. Such changes in K3T3 cells were brought about by E administered via serum (FBS-E). A 6% agarose chromatography of FBS-E demonstrated that E is associated predominantly with albumin, liposomes, and to a small extent with LDL, HDL and micelles. Since the physiological carriers for E are lipoproteins (LP), the authors have examined the relative efficacy of receptor-mediated transfer of E from LP and nonspecific transfer from FBS-E to HepG2 cells. Plasma from 3 human subjects who ingested 1200 IU E/day for 5 days was used for LP-E isolation. During a 48 hrs culture in log-phase, the cells incorporated 3.7 ..mu..g/culture (23%) from FBS-E at 2 ..mu..g/ml, whereas similar amounts were incorporated from LDL-E and HDL-E administered at lower concentrations. E-treated HepG2 cultures via FBS-E methods showed a 39% and 29% reduction in incorporation of (/sup 3/H)-galactose (GAL) and (/sup 3/H)-N-acetylmannosamine (NAM), respectively into cellular and shed GC. Similar reduction in glycosylation of GC was detected by GAL and NAM incorporation in cells treated with a lower amount of LDL-E or HDL-E. These results indicate that E-dependent modulation of glycosylation is more sensitive to LP-E than to FBS-E.

  19. Perilla Oil Supplementation Ameliorates High-Fat/High-Cholesterol Diet Induced Nonalcoholic Fatty Liver Disease in Rats via Enhanced Fecal Cholesterol and Bile Acid Excretion.

    PubMed

    Chen, Ting; Yuan, Fahu; Wang, Hualin; Tian, Yu; He, Lei; Shao, Yang; Li, Na; Liu, Zhiguo

    2016-01-01

    Recent experimental studies and clinical trials have shown that hepatic cholesterol metabolic disorders are closely related to the development of nonalcoholic fatty liver disease (NAFLD). The main goal of this study was to investigate the efficacy of the perilla oil rich in alpha-linolenic acid (ALA) against NASH and gain a deep insight into its potential mechanisms. Rats were fed a high-fat/high-cholesterol diet (HFD) supplement with perilla oil (POH) for 16 weeks. Routine blood biochemical tests and histological staining illustrated that the perilla oil administration improved HFD-induced hyperlipidemia, reduced hepatic steatosis, and inhibited hepatic inflammatory infiltration and fibrosis. Perilla oil also increased fecal bile acid and cholesterol excretion. Hepatic RNA-Seq analysis found that the long time perilla oil supplement notably modified the gene expression involved in cholesterol metabolism. Our results implicate that, after long-term high level dietary cholesterol feeding, rat liver endogenous synthesis of cholesterol and cholesterol-rich low density lipoprotein uptake was significantly inhibited, and perilla oil did not modulate expression of genes responsible for cholesterol synthesis but did increase cholesterol removed from hepatocytes by conversion to bile acids and increased fecal cholesterol excretion.

  20. Perilla Oil Supplementation Ameliorates High-Fat/High-Cholesterol Diet Induced Nonalcoholic Fatty Liver Disease in Rats via Enhanced Fecal Cholesterol and Bile Acid Excretion

    PubMed Central

    Tian, Yu; He, Lei; Shao, Yang; Li, Na

    2016-01-01

    Recent experimental studies and clinical trials have shown that hepatic cholesterol metabolic disorders are closely related to the development of nonalcoholic fatty liver disease (NAFLD). The main goal of this study was to investigate the efficacy of the perilla oil rich in alpha-linolenic acid (ALA) against NASH and gain a deep insight into its potential mechanisms. Rats were fed a high-fat/high-cholesterol diet (HFD) supplement with perilla oil (POH) for 16 weeks. Routine blood biochemical tests and histological staining illustrated that the perilla oil administration improved HFD-induced hyperlipidemia, reduced hepatic steatosis, and inhibited hepatic inflammatory infiltration and fibrosis. Perilla oil also increased fecal bile acid and cholesterol excretion. Hepatic RNA-Seq analysis found that the long time perilla oil supplement notably modified the gene expression involved in cholesterol metabolism. Our results implicate that, after long-term high level dietary cholesterol feeding, rat liver endogenous synthesis of cholesterol and cholesterol-rich low density lipoprotein uptake was significantly inhibited, and perilla oil did not modulate expression of genes responsible for cholesterol synthesis but did increase cholesterol removed from hepatocytes by conversion to bile acids and increased fecal cholesterol excretion. PMID:27642591

  1. Perilla Oil Supplementation Ameliorates High-Fat/High-Cholesterol Diet Induced Nonalcoholic Fatty Liver Disease in Rats via Enhanced Fecal Cholesterol and Bile Acid Excretion

    PubMed Central

    Tian, Yu; He, Lei; Shao, Yang; Li, Na

    2016-01-01

    Recent experimental studies and clinical trials have shown that hepatic cholesterol metabolic disorders are closely related to the development of nonalcoholic fatty liver disease (NAFLD). The main goal of this study was to investigate the efficacy of the perilla oil rich in alpha-linolenic acid (ALA) against NASH and gain a deep insight into its potential mechanisms. Rats were fed a high-fat/high-cholesterol diet (HFD) supplement with perilla oil (POH) for 16 weeks. Routine blood biochemical tests and histological staining illustrated that the perilla oil administration improved HFD-induced hyperlipidemia, reduced hepatic steatosis, and inhibited hepatic inflammatory infiltration and fibrosis. Perilla oil also increased fecal bile acid and cholesterol excretion. Hepatic RNA-Seq analysis found that the long time perilla oil supplement notably modified the gene expression involved in cholesterol metabolism. Our results implicate that, after long-term high level dietary cholesterol feeding, rat liver endogenous synthesis of cholesterol and cholesterol-rich low density lipoprotein uptake was significantly inhibited, and perilla oil did not modulate expression of genes responsible for cholesterol synthesis but did increase cholesterol removed from hepatocytes by conversion to bile acids and increased fecal cholesterol excretion.

  2. Perilla Oil Supplementation Ameliorates High-Fat/High-Cholesterol Diet Induced Nonalcoholic Fatty Liver Disease in Rats via Enhanced Fecal Cholesterol and Bile Acid Excretion.

    PubMed

    Chen, Ting; Yuan, Fahu; Wang, Hualin; Tian, Yu; He, Lei; Shao, Yang; Li, Na; Liu, Zhiguo

    2016-01-01

    Recent experimental studies and clinical trials have shown that hepatic cholesterol metabolic disorders are closely related to the development of nonalcoholic fatty liver disease (NAFLD). The main goal of this study was to investigate the efficacy of the perilla oil rich in alpha-linolenic acid (ALA) against NASH and gain a deep insight into its potential mechanisms. Rats were fed a high-fat/high-cholesterol diet (HFD) supplement with perilla oil (POH) for 16 weeks. Routine blood biochemical tests and histological staining illustrated that the perilla oil administration improved HFD-induced hyperlipidemia, reduced hepatic steatosis, and inhibited hepatic inflammatory infiltration and fibrosis. Perilla oil also increased fecal bile acid and cholesterol excretion. Hepatic RNA-Seq analysis found that the long time perilla oil supplement notably modified the gene expression involved in cholesterol metabolism. Our results implicate that, after long-term high level dietary cholesterol feeding, rat liver endogenous synthesis of cholesterol and cholesterol-rich low density lipoprotein uptake was significantly inhibited, and perilla oil did not modulate expression of genes responsible for cholesterol synthesis but did increase cholesterol removed from hepatocytes by conversion to bile acids and increased fecal cholesterol excretion. PMID:27642591

  3. A review on lecithin:cholesterol acyltransferase deficiency.

    PubMed

    Saeedi, Ramesh; Li, Min; Frohlich, Jiri

    2015-05-01

    Lecithin cholesterol acyl transferase (LCAT) is a plasma enzyme which esterifies cholesterol, and plays a key role in the metabolism of high-density lipoprotein cholesterol (HDL-C). Genetic disorders of LCAT are associated with lipoprotein abnormalities including low levels of HDL-C and presence of lipoprotein X, and clinical features mainly corneal opacities, changes in erythrocyte morphology and renal failure. Recombinant LCAT is being developed for the treatment of patients with LCAT deficiency. PMID:25172171

  4. Reduction of low-density lipoprotein cholesterol, plasma viscosity, and whole blood viscosity by the application of pulsed corona discharges and filtration

    NASA Astrophysics Data System (ADS)

    Jung, Jin M.; Fridman, Alexander; Cho, Daniel J.; Cho, Young I.

    2013-03-01

    The present study investigated the feasibility of applying pulsed corona discharges to blood plasma to reduce the viscosity of blood plasma and whole blood. Blood plasma was separated from blood cells, treated with corona discharges, and filtered before it was re-mixed with blood cells. Plasma viscosity (PV), whole blood viscosity (WBV), and low-density lipoprotein (LDL)-c concentration were measured before and after the corona treatment and filtration. Both PV and WBV increased in the case of the corona treatment only, whereas both of them decreased in the case of the corona treatment plus filtration. In particular, the LDL-c decreased in the case of the corona treatment plus filtration by 31.5% from the baseline value. The effect of the corona treatment on the reduction of the WBV was significant at low shear rates, but not at high shear rates, suggesting that the precipitation of the molecules in blood plasma by the corona treatment and subsequent removal may suppress the aggregation of erythrocytes and improve rheological properties of blood.

  5. Reduction of low-density lipoprotein cholesterol, plasma viscosity, and whole blood viscosity by the application of pulsed corona discharges and filtration.

    PubMed

    Jung, Jin M; Fridman, Alexander; Cho, Daniel J; Cho, Young I

    2013-03-01

    The present study investigated the feasibility of applying pulsed corona discharges to blood plasma to reduce the viscosity of blood plasma and whole blood. Blood plasma was separated from blood cells, treated with corona discharges, and filtered before it was re-mixed with blood cells. Plasma viscosity (PV), whole blood viscosity (WBV), and low-density lipoprotein (LDL)-c concentration were measured before and after the corona treatment and filtration. Both PV and WBV increased in the case of the corona treatment only, whereas both of them decreased in the case of the corona treatment plus filtration. In particular, the LDL-c decreased in the case of the corona treatment plus filtration by 31.5% from the baseline value. The effect of the corona treatment on the reduction of the WBV was significant at low shear rates, but not at high shear rates, suggesting that the precipitation of the molecules in blood plasma by the corona treatment and subsequent removal may suppress the aggregation of erythrocytes and improve rheological properties of blood.

  6. α-Defensins Induce a Post-translational Modification of Low Density Lipoprotein (LDL) That Promotes Atherosclerosis at Normal Levels of Plasma Cholesterol.

    PubMed

    Abu-Fanne, Rami; Maraga, Emad; Abd-Elrahman, Ihab; Hankin, Aviel; Blum, Galia; Abdeen, Suhair; Hijazi, Nuha; Cines, Douglas B; Higazi, Abd Al-Roof

    2016-02-01

    Approximately one-half of the patients who develop clinical atherosclerosis have normal or only modest elevations in plasma lipids, indicating that additional mechanisms contribute to pathogenesis. In view of increasing evidence that inflammation contributes to atherogenesis, we studied the effect of human neutrophil α-defensins on low density lipoprotein (LDL) trafficking, metabolism, vascular deposition, and atherogenesis using transgenic mice expressing human α-defensins in their polymorphonuclear leukocytes (Def(+/+)). Accelerated Def(+/+) mice developed α-defensin·LDL complexes that accelerate the clearance of LDL from the circulation accompanied by enhanced vascular deposition and retention of LDL, induction of endothelial cathepsins, increased endothelial permeability to LDL, and the development of lipid streaks in the aortic roots when fed a regular diet and at normal plasma levels of LDL. Transplantation of bone marrow from Def(+/+) to WT mice increased LDL clearance, increased vascular permeability, and increased vascular deposition of LDL, whereas transplantation of WT bone marrow to Def(+/+) mice prevented these outcomes. The same outcome was obtained by treating Def(+/+) mice with colchicine to inhibit the release of α-defensins. These studies identify a potential new link between inflammation and the development of atherosclerosis. PMID:26518877

  7. Stimulation of mast cells leads to cholesterol accumulation in macrophages in vitro by a mast cell granule-mediated uptake of low density lipoprotein

    SciTech Connect

    Kokkonen, J.O.; Kovanen, P.T.

    1987-04-01

    The uptake of low density lipoprotein (LDL) by cultured mouse macrophages was markedly promoted by isolated rat mast cell granules present in the culture medium. The granule-mediated uptake of /sup 125/I-LDL enhanced the rate of cholesteryl ester synthesis in the macrophages, the result being accumulation of cholesteryl esters in these cells. Binding of LDL to the granules was essential for the granule-mediated uptake of LDL by macrophages, for the uptake process was prevented by treating the granules with avidin or protamine chloride or by treating LDL with 1,2-cyclohexanedione, all of which inhibit the binding of LDL to the granules. Inhibition of granule phagocytosis by the macrophages with cytochalasin B also abolished the granule-mediated uptake of LDL. Finally, mouse macrophage monolayers and LDL were incubated in the presence of isolated rat serosal mast cells. Stimulation of the mast cells with compound 48/80, a degranulating agent, resulted in dose-dependent release of secretory granules from the mast cells and a parallel increase in /sup 14/C cholesteryl ester synthesis in the macrophages. The results show that, in this in vitro model, the sequence of events leading to accumulation of cholesteryl esters in macrophages involves initial stimulation of mast cells, subsequent release of their secretory granules, binding of LDL to the exocytosed granules, and, finally, phagocytosis of the LDL-containing granules by macrophages.

  8. Cholesterol efflux capacity: An introduction for clinicians.

    PubMed

    Anastasius, Malcolm; Kockx, Maaike; Jessup, Wendy; Sullivan, David; Rye, Kerry-Anne; Kritharides, Leonard

    2016-10-01

    Epidemiologic studies have shown an inverse correlation between high-density lipoprotein (HDL) cholesterol (HDL-C) levels and cardiovascular disease outcomes. However, the hypothesis of a causal relationship between HDL-C and cardiovascular disease has been challenged by genetic and clinical studies. Serum cholesterol efflux capacity (CEC) is an important measure of HDL function in humans. Recent large clinical studies have shown a correlation between in vitro CEC and cardiovascular disease prevalence and incidence, which appears to be independent of HDL-C concentration. The present review summarizes recent large clinical studies and introduces important methodological considerations. Further studies are required to standardize and establish the reproducibility of this measure of HDL function and clarify whether modulating CEC will emerge as a useful therapeutic target. PMID:27659883

  9. Plasma cholesterol transport in anhepatic rats.

    PubMed Central

    Quarfordt, S H; Landis, B; Cucchiaro, G; Yamaguchi, Y; Oswald, B

    1992-01-01

    The plasma appearance of newly synthesized cholesterol in anhepatic laboratory diet-fed rats was 10% of the intact rat. In intact rats this cholesterol was mainly ester in lower density lipoproteins, but for anhepatic rats it was virtually only free in high density lipoprotein. Chylomicron cholesterol ester was removed much more slowly from anhepatic than control plasma and returned primarily as free in high density lipoproteins, with the control return 10 times the anhepatic return. Lower density lipoprotein cholesterol ester transfer to an extravascular pool in anhepatic rats was less than 10% of controls. The liver was responsible for 95% of the extravascular lower density lipoprotein ester pool and only 50% of the for high density lipoprotein ester. Despite decreased anhepatic lipoprotein catabolism, the mass of both plasma low and high density lipoproteins progressively decreased indicating an even greater decrease in influx. The anhepatic fractional catabolic rate of apo A1 was similar to controls, but that of apo E was considerably less. Despite the unchanged catabolism of apo A1 and the reduced catabolism of apo E, plasma apo A1 decreased less than apo E after hepatectomy. The anhepatic data confirm the pivotal role of the liver in maintaining plasma low and high density lipoprotein cholesterol concentrations. They suggest that, in addition to its anabolic and catabolic functions, the liver also acts as a reservoir buffering changes in plasma concentration. Images PMID:1569195

  10. Modulation of the kinetics of 3β-hydroxy-5-oxo-5,6-secocholestan-6-al/phosphatidylethanolamine Schiff base formation by cholesterol and cholesterol crystallization.

    PubMed

    Bach, D; Wachtel, E; Miller, I R

    2015-02-01

    We have previously shown that the oxidized cholesterol 3β-hydroxy-5-oxo-5,6-secocholestan-6-al (atheronal A) reacts covalently with the free amino group of phosphatidylethanolamine (PE) or phosphatidylserine (PS) to produce a Schiff base. Accompanying this interaction, the biophysical properties of the phospholipid membranes are also changed. In the present report, we extend our earlier study of the rate of Schiff base formation in dimyristoyl PE/atheronal A binary mixtures to the more biologically relevant case in which varying amounts of cholesterol are also present. Using optical spectroscopy to monitor reaction kinetics, we demonstrate that the presence of cholesterol reduces the accessibility of the aldehyde moiety of the atheronal A to the free headgroup amine. We also find that the presence of atheronal A promotes the early onset of cholesterol crystallization in the ternary mixtures, perhaps with the Schiff base serving as a site for heterogeneous nucleation.

  11. Annexin A6 and Late Endosomal Cholesterol Modulate Integrin Recycling and Cell Migration.

    PubMed

    García-Melero, Ana; Reverter, Meritxell; Hoque, Monira; Meneses-Salas, Elsa; Koese, Meryem; Conway, James R W; Johnsen, Camilla H; Alvarez-Guaita, Anna; Morales-Paytuvi, Frederic; Elmaghrabi, Yasmin A; Pol, Albert; Tebar, Francesc; Murray, Rachael Z; Timpson, Paul; Enrich, Carlos; Grewal, Thomas; Rentero, Carles

    2016-01-15

    Annexins are a family of proteins that bind to phospholipids in a calcium-dependent manner. Earlier studies implicated annexin A6 (AnxA6) to inhibit secretion and participate in the organization of the extracellular matrix. We recently showed that elevated AnxA6 levels significantly reduced secretion of the extracellular matrix protein fibronectin (FN). Because FN is directly linked to the ability of cells to migrate, this prompted us to investigate the role of AnxA6 in cell migration. Up-regulation of AnxA6 in several cell models was associated with reduced cell migration in wound healing, individual cell tracking and three-dimensional migration/invasion assays. The reduced ability of AnxA6-expressing cells to migrate was associated with decreased cell surface expression of αVβ3 and α5β1 integrins, both FN receptors. Mechanistically, we found that elevated AnxA6 levels interfered with syntaxin-6 (Stx6)-dependent recycling of integrins to the cell surface. AnxA6 overexpression caused mislocalization and accumulation of Stx6 and integrins in recycling endosomes, whereas siRNA-mediated AnxA6 knockdown did not modify the trafficking of integrins. Given our recent findings that inhibition of cholesterol export from late endosomes (LEs) inhibits Stx6-dependent integrin recycling and that elevated AnxA6 levels cause LE cholesterol accumulation, we propose that AnxA6 and blockage of LE cholesterol transport are critical for endosomal function required for Stx6-mediated recycling of integrins in cell migration.

  12. Isoflavones and phytosterols contained in Xuezhikang capsules modulate cholesterol homeostasis in high-fat diet mice

    PubMed Central

    Feng, Dong; Sun, Jian-guo; Sun, Run-bin; Ou-Yang, Bing-chen; Yao, Lan; Aa, Ji-ye; Zhou, Fang; Zhang, Jing-wei; Zhang, Jian; Wang, Guang-ji

    2015-01-01

    Aim: Xuezhikang (XZK), an extract of red yeast rice, has been widely used in traditional Chinese medicine to treat cardiovascular disease. Three fractions F1, F2 and F3 (primarily containing isoflavones, monacolins or phytosterols, respectively) are extracted from Xuezhikang capsules. In this study we evaluated the lipid-lowering effects of these fractions and explored the potential mechanisms of actions. Methods: Mice treated with a high-fat diet (HFD) were orally adminis¬tered lovastatin (10 mg·kg−1·d−1), XZK (1200 mg·kg−1·d−1), F1 (27.5 mg·kg−1·d−1), F2 (11.3 mg·kg−1·d−1) or F3 (35 mg·kg−1·d−1) for 10 weeks. Lipids were measured using commercial enzymatic kits, and the mRNA and protein levels of genes involved in cholesterol and bile acid homeostasis were evaluated using qRT-PCR and Western blot analysis, respectively. Results: XZK increased the fecal excretion of lipids and bile acids, reduced serum TC, TG and LDL-C levels by 40%, 55% and 46%, respectively, and increased serum HDL-C by 31%. Administration of F1 repressed serum TC and TG by 24% and 52%, respectively, and elevated hepatic synthesis of CYP7A1. It also increased hepatic elimination of bile acids in the fecal excretions by 79% through upregulating BSEP and downregulating NTCP. Administration of F3 decreased serum TC, TG and LDL-C levels by 33%, 29% and 39%, respectively, and increased serum HDL-C by 28%, sig¬nificantly reduced intestinal absorption of cholesterol by inhibiting the transcription of NPC1L1, and elevated excretion of TC, FC and CE by 96%, 72% and 101%, respectively. Administration of F2 showed pharmacological effects similar to those of lovastatin. Conclusion: Isoflavones and phytosterols in XZK exert cholesterol-lowering effects in HFD mice through mechanisms that differ from those of lovastatin. Isoflavones and phytosterols act in a complimentary manner: through enhancing the elimination of bile acids and reducing intestinal cholesterol absorption

  13. Major Risk Factors for Heart Disease: High Blood Cholesterol

    MedlinePlus

    ... lipoprotein profile test will also measure levels of triglycerides, another fatty substance in the blood. (See "What Are Triglycerides?" .) * Cholesterol levels are measured in milligrams (mg) of ...

  14. Krill oil supplementation lowers serum triglycerides without increasing low-density lipoprotein cholesterol in adults with borderline high or high triglyceride levels.

    PubMed

    Berge, Kjetil; Musa-Veloso, Kathy; Harwood, Melody; Hoem, Nils; Burri, Lena

    2014-02-01

    The aim of the study was to explore the effects of 12 weeks daily krill oil supplementation on fasting serum triglyceride (TG) and lipoprotein particle levels in subjects whose habitual fish intake is low and who have borderline high or high fasting serum TG levels (150-499 mg/dL). We hypothesized that Krill oil lowers serum TG levels in subjects with borderline high or high fasting TG levels. To test our hypothesis 300 male and female subjects were included in a double-blind, randomized, multi-center, placebo-controlled study with five treatment groups: placebo (olive oil) or 0.5, 1, 2, or 4 g/day of krill oil. Serum lipids were measured after an overnight fast at baseline, 6 and 12 weeks. Due to a high intra-individual variability in TG levels, data from all subjects in the four krill oil groups were pooled to increase statistical power, and a general time- and dose-independent one-way analysis of variance was performed to assess efficacy. Relative to subjects in the placebo group, those administered krill oil had a statistically significant calculated reduction in serum TG levels of 10.2%. Moreover, LDL-C levels were not increased in the krill oil groups relative to the placebo group. The outcome of the pooled analysis suggests that krill oil is effective in reducing a cardiovascular risk factor. However, owing to the individual fluctuations of TG concentrations measured, a study with more individual measurements per treatment group is needed to increase the confidence of these findings. PMID:24461313

  15. Goal attainments and their discrepancies for low density lipoprotein cholesterol (LDL-C) and apolipoprotein B (apo B) in over 2,000 Chinese patients with known coronary artery disease or type 2 diabetes

    PubMed Central

    Yang, Xiang-Jun; Zhao, Xin; Xu, Hai-Feng

    2015-01-01

    Purpose Low density lipoprotein cholesterol (LDL-C) is primary treatment target for patients with dislipidemia. The apolipoprotein B (apo B), an emerging biomarker for cardiovascular risk prediction, appears to be superior to the LDL-C. However, little is known about goal attainments and their discrepancies for LDL-C and apo B in Chinese patients with known CAD or DM. Methods A total of 2,172 hospitalized patients with known coronary artery disease (CAD) or DM, aged >27 years of old, were enrolled. The success rates for apo B and LDL-C goal attainments were evaluated and compared by categorization and by sex. Results When the success rates for apo B were compared with the ones for LDL-C, the former was higher than the latter across all categorizations, with the statistically significant differences seen in all patients, CAD alone and DM alone (P<0.0001), but not in coexistence of CAD and DM (P=0.190). The trend toward to higher success rates for LDL-C and apo B goal attainments in men than in women were noteworthy across all categorizations although only in all patients and in DM alone patients were the statistically significant differences found (P<0.01). Conclusions The LDL-C lags behind the apo B in goal attainments in Chinese patients. Whether these discrepancies are associated with the occurrence differences for CAD and for stroke between the East Asia and the Western countries warrants further study. PMID:25984449

  16. Cholesterol enhances amyloid {beta} deposition in mouse retina by modulating the activities of A{beta}-regulating enzymes in retinal pigment epithelial cells

    SciTech Connect

    Wang, Jiying; Ohno-Matsui, Kyoko; Morita, Ikuo

    2012-08-10

    age-matched mice fed standard rodent chow diet did not. Activities and mRNA levels of NEP and {alpha}-secretase were significantly lower in native RPE cells freshly isolated from cholesterol-enriched chow fed mice compared to standard rodent chow fed mice. These findings suggest that cholesterol enhances subretinal A{beta} accumulation by modulating the activities of enzymes degrading and processing A{beta} in RPE cells in senescent subjects.

  17. Equilibrium-fluctuation-analysis of single liposome binding events reveals how cholesterol and Ca2+ modulate glycosphingolipid trans-interactions.

    PubMed

    Kunze, Angelika; Bally, Marta; Höök, Fredrik; Larson, Göran

    2013-01-01

    Carbohydrate-carbohydrate interactions (CCIs) are of central importance for several biological processes. However, the ultra-weak nature of CCIs generates difficulties in studying this interaction, thus only little is known about CCIs. Here we present a highly sensitive equilibrium-fluctuation-analysis of single liposome binding events to supported lipid bilayers (SLBs) based on total internal reflection fluorescence (TIRF) microscopy that allows us to determine apparent kinetic rate constants of CCIs. The liposomes and SLBs both contained natural Le(x) glycosphingolipids (Galβ4(Fucα3)GlcNAcβ3Galβ4Glcβ1Cer), which were employed to mimic cell-cell contacts. The kinetic parameters of the self-interaction between Le(x)-containing liposomes and SLBs were measured and found to be modulated by bivalent cations. Even more interestingly, upon addition of cholesterol, the strength of the CCIs increases, suggesting that this interaction is strongly influenced by a cholesterol-dependent presentation and/or spatial organization of glycosphingolipids in cell membranes. PMID:23486243

  18. The effects of ABCG5/G8 polymorphisms on plasma HDL cholesterol concentrations depend on smoking habit in the Boston Puerto Rican Health Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background-Low high-density lipoprotein cholesterol (HDL-C) is associated with an increased risk for atherosclerosis and concentrations are modulated by genetic and environmental factors such as smoking. Objective- To assess whether the association of common single nucleotide polymorphisms (SNPs...

  19. Heterogeneity of cholesterol homeostasis in man. Response to changes in dietary fat quality and cholesterol quantity.

    PubMed Central

    McNamara, D J; Kolb, R; Parker, T S; Batwin, H; Samuel, P; Brown, C D; Ahrens, E H

    1987-01-01

    Studies were carried out to examine the effects of dietary fat and cholesterol on cholesterol homeostasis in man. 75 12-wk studies were carried out during intake of 35% of calories as either saturated or polyunsaturated fat, first low and then high in dietary cholesterol. Dietary fat and cholesterol intakes, plasma lipid and lipoprotein levels, cholesterol absorption and sterol synthesis in isolated blood mononuclear leukocytes were measured during each diet period. In 69% of the studies the subjects compensated for the increased cholesterol intake by decreasing cholesterol fractional absorption and/or endogenous cholesterol synthesis. When an increase in plasma cholesterol levels was observed there was a failure to suppress endogenous cholesterol synthesis. Plasma cholesterol levels were more sensitive to dietary fat quality than to cholesterol quantity. The results demonstrate that the responses to dietary cholesterol and fat are highly individualized and that most individuals have effective feedback control mechanisms. PMID:3584466

  20. 1-[4-[4[(4R,5R)-3,3-Dibutyl-7-(dimethylamino)-2,3,4,5-tetrahydro-4-hydroxy-1,1-dioxido-1-benzothiepin-5-yl]phenoxy]butyl]-4-aza-1-azoniabicyclo[2.2.2]octane methanesulfonate (SC-435), an ileal apical sodium-codependent bile acid transporter inhibitor alters hepatic cholesterol metabolism and lowers plasma low-density lipoprotein-cholesterol concentrations in guinea pigs.

    PubMed

    West, Kristy L; Ramjiganesh, Tripurasundari; Roy, Suheeta; Keller, Bradley T; Fernandez, Maria Luz

    2002-10-01

    Male Hartley guinea pigs (10/group) were assigned either to a control diet (no drug treatment) or to diets containing 0.4, 2.2, or 7.3 mg/day of an ileal apical sodium-codependent bile acid transporter (ASBT) inhibitor, 1-[4-[4[(4R,5R)-3,3-dibutyl-7-(dimethylamino)-2,3,4,5-tetrahydro-4-hydroxy-1,1-dioxido-1-benzothiepin-5-yl]phenoxy]butyl]-4-aza-1-azoniabicyclo[2.2.2] octane methanesulfonate (SC-435). Based on food consumption, guinea pigs received 0, 0.8, 3.7, or 13.4 mg/kg/day of the ASBT inhibitor. The amount of cholesterol in the four diets was maintained at 0.17%, equivalent to 1200 mg/day in the human situation. Guinea pigs treated with 13.4 mg/kg/day SC-435 had 41% lower total cholesterol and 44% lower low-density lipoprotein (LDL)-cholesterol concentrations compared with control (P < 0.01), whereas no significant differences were observed with either of the lower doses of SC-435. Hepatic cholesterol esters were significantly reduced by 43, 56, and 70% in guinea pigs fed 0.8, 3.7, and 13.4 mg/kg/day of the ASBT inhibitor, respectively (P < 0.01). In addition, the highest dose of the inhibitor resulted in a 42% increase in the number of very low-density lipoprotein (VLDL) triacylglycerol molecules and a larger VLDL diameter compared with controls (P < 0.05). Acyl-CoA cholesterol/acyltransferase activity was 30% lower with the highest dose treatment, whereas cholesterol 7alpha-hydroxylase, the regulatory enzyme of bile acid synthesis, was 30% higher with the highest ASBT inhibitor dose (P < 0.05). Furthermore, bile acid excretion increased 2-fold with the highest dose of SC-435 compared with the control group (P < 0.05). These results suggest that the reduction in total and LDL-cholesterol concentrations by the ASBT inhibitor is a result of alterations in hepatic cholesterol metabolism due to modifications in the enterohepatic circulation of bile acids.

  1. Conditions that may result in (de-)phosphorylation of hepatic acyl-CoA:cholesterol acyltransferase result also in modulation of substrate supply in vitro.

    PubMed Central

    Mitropoulos, K A; Venkatesan, S

    1984-01-01

    The present experiments were designed to study intervesicular transfer of cholesterol in rat liver microsomal fraction and modulation of the activity of acyl-CoA:cholesterol acyltransferase (ACAT) under conditions that are expected to result in the covalent modification (phosphorylation/dephosphorylation) of the enzyme. Preincubation of rat liver microsomal fraction followed by assay of ACAT showed a time-dependent increase in activity. This rate was temperature-dependent. Preincubation in the presence of cholesterol/phospholipid liposomes resulted in a time-dependent transfer of cholesterol from liposomal to the microsomal vesicles and in an increase in the rate of ACAT change owing to the preincubation. Both these rates were dependent on liposomal cholesterol concentration and on temperature. The presence of cytosol in the preincubation mixture increased the rate of change of ACAT activity in the absence or in the presence of cholesterol/phospholipid liposomes. In the latter case the presence of cytosol also increased the rate of transfer of cholesterol from liposomal to the microsomal vesicles. Activation energies of the rate of this transfer and of the rate of increase of ACAT activity were similar in the presence and in the absence of cytosol. Both in the absence and in the presence of cytosol, the presence of NaF (50 mM) in the preincubation mixture considerably decreased the rate of transfer of cholesterol from liposomal to microsomal vesicles and the rate of increase of ACAT activity. The presence of Mg2+ in the preincubation mixture produced no effect on the rate of transfer of cholesterol from liposomal to the microsomal vesicles, although under most conditions it decreased the rate of increase of ACAT activity caused by the preincubation. These results are discussed in relation to the molecular mechanism involved in this intervesicular transfer of cholesterol and to the modulation of ACAT activity by substrate supply, and also in relation to the

  2. Prosopis farcta beans increase HDL cholesterol and decrease LDL cholesterol in ostriches (Struthio camelus).

    PubMed

    Omidi, Arash; Ansari nik, Hossein; Ghazaghi, Mahmood

    2013-02-01

    Ten blue-neck male ostriches (Struthio camelus) were fed Prosopis farcta beans throughout a 30-day experiment. Blood samples were collected from ostriches on days 0 and 30 to measure levels of high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, triglyceride, total serum protein, albumin, globulin, cholesterol, calcium, inorganic phosphorus, the activity of aspartate aminotransferase, alanine aminotransferase, and γ-glutamyl transferase (γ-GT). From days 0 to 30, HDL cholesterol, total protein, and globulins levels increased significantly whereas LDL cholesterol, inorganic phosphorus, and γ-GT activity decreased significantly.

  3. Impact of Combined C-Reactive Protein and High-Density Lipoprotein Cholesterol Levels on Long-Term Outcomes in Patients With Coronary Artery Disease After a First Percutaneous Coronary Intervention.

    PubMed

    Ogita, Manabu; Miyauchi, Katsumi; Tsuboi, Shuta; Shitara, Jun; Endo, Hirohisa; Wada, Hideki; Doi, Shinichiro; Naito, Ryo; Konishi, Hirokazu; Dohi, Tomotaka; Kasai, Takatoshi; Tamura, Hiroshi; Okazaki, Shinya; Suwa, Satoru; Daida, Hiroyuki

    2015-10-01

    Cardiovascular risk persists despite intensive low-density lipoprotein cholesterol (LDL-C) reduction using statins. High-density lipoprotein (HDL-C) is inversely associated with coronary artery disease (CAD) that is independent of LDL-C levels. C-reactive protein (CRP) is an established marker of inflammation that can impair the protective function of HDL-C: however, the impact of inflammation on the association between HDL-C and long-term outcomes in patients with CAD under statin therapy remains uncertain. We prospectively enrolled 3,507 consecutive patients with CAD who underwent a first percutaneous coronary intervention (PCI) from 1997 to 2011 at our institution. We stratified 1,682 patients (48%) who had been treated with statin at the time of PCI into 4 groups according to HDL-C levels (cutoffs of 40 and 50 mg/dl for men and women, respectively) and a CRP cutoff of 2 mg/dl: (1) high HDL-C/low CRP, (2) high HDL-C/high CRP, (3) low HDL-C/low CRP, and (4) low HDL-C/high CRP comparing the rates of all-cause death among them. The median follow-up period was 1,985 days (interquartile range 916 to 3,183 days). During this period, 197 patients (11.7%) died because of cardiac death (n = 58), carcinoma (n = 61), stroke (n = 10), and other causes (n = 69). The rates of all-cause death significantly differed among the groups (log-rank test, p <0.0001). In multivariate Cox hazard regression analyses, low HDL-C with high CRP levels remained significantly associated with a higher rate of all-cause death even after adjustment for other co-variates (hazard ratio 2.38, 1.59 to 3.61, p <0.0001). Low HDL-C together with elevated CRP levels is significantly associated with long-term outcomes in patients who received statin therapy after PCI.

  4. Serum Non-high-density lipoprotein cholesterol concentration and risk of death from cardiovascular diseases among U.S. adults with diagnosed diabetes: the Third National Health and Nutrition Examination Survey linked mortality study

    PubMed Central

    2011-01-01

    Background Non-high-density lipoprotein cholesterol (non-HDL-C) measures all atherogenic apolipoprotein B-containing lipoproteins and predicts risk of cardiovascular diseases (CVD). The association of non-HDL-C with risk of death from CVD in diabetes is not well understood. This study assessed the hypothesis that, among adults with diabetes, non-HDL-C may be related to the risk of death from CVD. Methods We analyzed data from 1,122 adults aged 20 years and older with diagnosed diabetes who participated in the Third National Health and Nutrition Examination Survey linked mortality study (299 deaths from CVD according to underlying cause of death; median follow-up length, 12.4 years). Results Compared to participants with serum non-HDL-C concentrations of 35 to 129 mg/dL, those with higher serum levels had a higher risk of death from total CVD: the RRs were 1.34 (95% CI: 0.75-2.39) and 2.25 (95% CI: 1.30-3.91) for non-HDL-C concentrations of 130-189 mg/dL and 190-403 mg/dL, respectively (P = 0.003 for linear trend) after adjustment for demographic characteristics and selected risk factors. In subgroup analyses, significant linear trends were identified for the risk of death from ischemic heart disease: the RRs were 1.59 (95% CI: 0.76-3.32) and 2.50 (95% CI: 1.28-4.89) (P = 0.006 for linear trend), and stroke: the RRs were 3.37 (95% CI: 0.95-11.90) and 5.81 (95% CI: 1.96-17.25) (P = 0.001 for linear trend). Conclusions In diabetics, higher serum non-HDL-C concentrations were significantly associated with increased risk of death from CVD. Our prospective data support the notion that reducing serum non-HDL-C concentrations may be beneficial in the prevention of excess death from CVD among affected adults. PMID:21605423

  5. Interleukin 28B polymorphisms are the only common genetic variants associated with low-density lipoprotein cholesterol (LDL-C) in genotype-1 chronic hepatitis C and determine the association between LDL-C and treatment response.

    PubMed

    Clark, P J; Thompson, A J; Zhu, M; Vock, D M; Zhu, Q; Ge, D; Patel, K; Harrison, S A; Urban, T J; Naggie, S; Fellay, J; Tillmann, H L; Shianna, K; Noviello, S; Pedicone, L D; Esteban, R; Kwo, P; Sulkowski, M S; Afdhal, N; Albrecht, J K; Goldstein, D B; McHutchison, J G; Muir, A J

    2012-05-01

    Low-density lipoprotein cholesterol (LDL-C) levels and interleukin 28B (IL28B) polymorphism are associated with sustained viral response (SVR) to peginterferon/ribavirin (pegIFN/RBV) for chronic hepatitis C (CHC) infection. IL28B has been linked with LDL-C levels using a candidate gene approach, but it is not known whether other genetic variants are associated with LDL-C, nor how these factors definitively affect SVR. We assessed genetic predictors of serum lipid and triglyceride levels in 1604 patients with genotype 1 (G1) chronic hepatitis C virus (HCV) infection by genome-wide association study and developed multivariable predictive models of SVR. IL28B polymorphisms were the only common genetic variants associated with pretreatment LDL-C level in Caucasians (rs12980275, P = 4.7 × 10(-17), poor response IL28B variants associated with lower LDL-C). The association was dependent on HCV infection, IL28B genotype was no longer associated with LDL-C in SVR patients after treatment, while the association remained significant in non-SVR patients (P < 0.001). LDL-C was significantly associated with SVR for heterozygous IL28B genotype patients (P < 0.001) but not for homozygous genotypes. SVR modelling suggested that IL28B heterozygotes with LDL-C > 130 mg/dL and HCV RNA ≤600 000 IU/mL may anticipate cure rates >80%, while the absence of these two criteria was associated with an SVR rate of <35%. IL28B polymorphisms are the only common genetic variants associated with pretreatment LDL-C in G1-HCV. LDL-C remains significantly associated with SVR for heterozygous IL28B genotype patients, where LDL-C and HCV RNA burden may identify those patients with high or low likelihood of cure with pegIFN/RBV therapy. PMID:22497812

  6. Clinical Impact of Rapid Reduction of Low-Density Lipoprotein Cholesterol Level on Long-Term Outcome of Acute Myocardial Infarction in the Statin Era: Subanalysis of the ALPS-AMI Study

    PubMed Central

    Miura, Takashi; Izawa, Atsushi; Motoki, Hirohiko; Miyashita, Yusuke; Kashima, Yuichiro; Ebisawa, Souichiro; Tomita, Takeshi; Koyama, Jun; Ikeda, Uichi

    2015-01-01

    Background The optimal period to achieve target percent reduction of low-density lipoprotein cholesterol (LDL-C) level for secondary prevention of acute myocardial infarction (AMI) is not well established. Methods The Assessment of Lipophilic vs. Hydrophilic Statin Therapy in AMI (ALPS-AMI) study enrolled 508 patients (mean age, 66.0± 11.6 years; 80.6% male) who were hospitalized for AMI and underwent percutaneous coronary intervention (PCI). Of these patients, 81 were excluded because of the absence of LDL-C measurements at 4 weeks after randomization. In the remaining 427 patients, the target LDL-C level reduction of ≥30% was achieved and not reached within 4 weeks after randomization in 204 cases (early reduction group) and 223 cases (late reduction group). The groups were formed prospectively and analyzed with regard to the composite end point (major adverse cardiovascular event [MACE]: all-cause death, myocardial infarction, and stroke) and clinical outcomes. Results MACE were significantly more frequent in the late reduction group compared to the early reduction group (9.4% vs. 3.4%, P = 0.013). The incidence of cardiac deaths was also significantly higher in the late reduction group (3.1% vs. 0.5%, P = 0.044). On age-adjusted Cox proportional hazards analysis in statin-naïve patients, percent reduction of LDL-C level during the initial 4 weeks (HR, 0.98; 95% CI: 0.97–0.99, P = 0.042) and baseline LDL-C level (HR, 0.98; 95% CI: 0.97–0.99, P = 0.033) predicted adverse events. Conclusions Rapid reduction of LDL-C level is strongly associated with favorable outcome in patients with AMI. PMID:26083546

  7. Low-Density Lipoprotein Cholesterol Concentrations and Association of High-Sensitivity C-Reactive Protein Concentrations With Incident Coronary Heart Disease in the Multi-Ethnic Study of Atherosclerosis.

    PubMed

    Lin, Gen-Min; Liu, Kiang; Colangelo, Laura A; Lakoski, Susan G; Tracy, Russell P; Greenland, Philip

    2016-01-01

    High-sensitivity C-reactive protein (hs-CRP) has been associated with coronary heart disease (CHD) in numerous but not all observational studies, and whether low levels of low-density lipoprotein cholesterol (LDL-C) alter this association is unknown. In the Multi-Ethnic Study of Atherosclerosis (2000-2012), we prospectively assessed the association of hs-CRP concentrations with incident CHD in participants who did not receive lipid-lowering therapy, as well as in those with LDL-C concentrations less than 130 mg/dL (n = 3,106) and those with LDL-C concentrations of 130 mg/dL or greater (n = 1,716) at baseline (2000-2002). Cox proportional hazard analyses were used to assess the associations after adjustment for socioeconomic status, traditional risk factors, body mass index, diabetes, aspirin use, kidney function, and coronary artery calcium score. Loge hs-CRP was associated with incident CHD in participants with LDL-C concentrations of 130 mg/dL or higher (hazard ratio (HR) = 1.29, 95% confidence interval (CI): 1.05, 1.60) but not in those with LDL-C concentrations less than 130 mg/dL (HR = 0.88, 95% CI: 0.74, 1.05; P for interaction = 0.003). As a whole, loge hs-CRP was not associated with incident CHD in participants who had not received lipid-lowering therapy at baseline (HR = 1.05, 95% CI: 0.92, 1.20) and who had mean LDL-C concentrations less than 130 mg/dL. These findings suggest that LDL-C concentrations might be a moderator of the contribution of hs-CRP to CHD.

  8. Effects of hormones on lipids and lipoproteins

    SciTech Connect

    Krauss, R.M.

    1991-12-01

    Levels of plasma lipids and lipoproteins are strong predictors for the development of atherosclerotic cardiovascular disease in postmenopausal women. In women, as in men, numerous factors contribute to variations in plasma lipoproteins that may affect cardiovascular disease risk. These include age, dietary components, adiposity, genetic traits, and hormonal changes. Each of these factors may operate to varying degrees in determining changes in plasma lipoprotein profiles accompanying menopause- Cross-sectional and longitudinal studies have suggested increases in levels of cholesterol, low density lipoproteins (LDL) and triglyceride-rich lipoproteins associated with menopause. High density lipoproteins (HDL), which are higher in women than men and are thought to contribute to relative protection of premenopausal women from cardiovascular disease, remain relatively constant in the years following menopause, although small, and perhaps transient reductions in the HDL{sub 2} subfraction have been reported in relation to reduced estradiol level following menopause. Despite these associations, it has been difficult to determine the role of endogenous hormones in influencing the plasma lipoproteins of postmenopausal women. In principle, the effects of hormone replacement should act to reverse any alterations in lipoprotein metabolism that are due to postmenopausal hormone changes. While there may be beneficial effects on lipoproteins, hormone treatment does not restore a premenopausal lipoprotein profile. Furthermore, it is not dear to what extent exogenous hormone-induced lipoprotein changes contribute to the reduced incidence of cardiovascular disease with hormone replacement therapy.

  9. Lipoprotein ratios: Physiological significance and clinical usefulness in cardiovascular prevention

    PubMed Central

    Millán, Jesús; Pintó, Xavier; Muñoz, Anna; Zúñiga, Manuel; Rubiés-Prat, Joan; Pallardo, Luis Felipe; Masana, Luis; Mangas, Alipio; Hernández-Mijares, Antonio; González-Santos, Pedro; Ascaso, Juan F; Pedro-Botet, Juan

    2009-01-01

    Low-density lipoprotein (LDL) cholesterol concentration has been the prime index of cardiovascular disease risk and the main target for therapy. However, several lipoprotein ratios or “atherogenic indices” have been defined in an attempt to optimize the predictive capacity of the lipid profile. In this review, we summarize their pathophysiological aspects, and highlight the rationale for using these lipoprotein ratios as cardiovascular risk factors in clinical practice, specifying their cut-off risk levels and a target for lipid-lowering therapy. Total/high-density lipoprotein (HDL) cholesterol and LDL/HDL cholesterol ratios are risk indicators with greater predictive value than isolated parameters used independently, particularly LDL. Future recommendations regarding the diagnosis and treatment of dyslipidemia, including instruments for calculating cardiovascular risk or action guidelines, should include the lipoprotein ratios with greater predictive power which, in view of the evidence-based results, are none other than those which include HDL cholesterol. PMID:19774217

  10. Gain-of-Function Lipoprotein Lipase Variant rs13702 Modulates Lipid Traits through Disruption of a MicroRNA-410 Seed Site

    PubMed Central

    Richardson, Kris; Nettleton, Jennifer A.; Rotllan, Noemi; Tanaka, Toshiko; Smith, Caren E.; Lai, Chao-Qiang; Parnell, Laurence D.; Lee, Yu-Chi; Lahti, Jari; Lemaitre, Rozenn N.; Manichaikul, Ani; Keller, Margaux; Mikkilä, Vera; Ngwa, Julius; van Rooij, Frank J.A.; Ballentyne, Christie M.; Borecki, Ingrid B.; Cupples, L. Adrienne; Garcia, Melissa; Hofman, Albert; Ferrucci, Luigi; Mozaffarian, Dariush; Perälä, Mia-Maria; Raitakari, Olli; Tracy, Russell P.; Arnett, Donna K.; Bandinelli, Stefania; Boerwinkle, Eric; Eriksson, Johan G.; Franco, Oscar H.; Kähönen, Mika; Nalls, Michael; Siscovick, David S.; Houston, Denise K.; Psaty, Bruce M.; Viikari, Jorma; Witteman, Jacqueline C.M.; Goodarzi, Mark O.; Lehtimäki, Terho; Liu, Yongmei; Zillikens, M. Carola; Chen, Yii-Der I.; Uitterlinden, André G.; Rotter, Jerome I.; Fernandez-Hernando, Carlos; Ordovas, Jose M.

    2013-01-01

    Genome-wide association studies (GWAS) have identified hundreds of genetic variants that are associated with lipid phenotypes. However, data supporting a functional role for these variants in the context of lipid metabolism are scarce. We investigated the association of the lipoprotein lipase (LPL) variant rs13702 with plasma lipids and explored its potential for functionality. The rs13702 minor allele had been predicted to disrupt a microRNA (miR) recognition element (MRE) seed site (MRESS) for the human microRNA-410 (miR-410). Furthermore, rs13702 is in linkage disequilibrium (LD) with several SNPs identified by GWAS. We performed a meta-analysis across ten cohorts of participants that showed a statistically significant association of rs13702 with triacylglycerols (TAG) (p = 3.18 × 10−42) and high-density lipoprotein cholesterol (HDL-C) (p = 1.35 × 10−32) with each copy of the minor allele associated with 0.060 mmol/l lower TAG and 0.041 mmol/l higher HDL-C. Our data showed that an LPL 3′ UTR luciferase reporter carrying the rs13702 major T allele was reduced by 40% in response to a miR-410 mimic. We also evaluated the interaction between intake of dietary fatty acids and rs13702. Meta-analysis demonstrated a significant interaction between rs13702 and dietary polyunsaturated fatty acid (PUFA) with respect to TAG concentrations (p = 0.00153), with the magnitude of the inverse association between dietary PUFA intake and TAG concentration showing −0.007 mmol/l greater reduction. Our results suggest that rs13702 induces the allele-specific regulation of LPL by miR-410 in humans. This work provides biological and potential clinical relevance for previously reported GWAS variants associated with plasma lipid phenotypes. PMID:23246289

  11. Phosphatidylcholine: Greasing the Cholesterol Transport Machinery

    PubMed Central

    Lagace, Thomas A.

    2015-01-01

    Negative feedback regulation of cholesterol metabolism in mammalian cells ensures a proper balance of cholesterol with other membrane lipids, principal among these being the major phospholipid phosphatidylcholine (PC). Processes such as cholesterol biosynthesis and efflux, cholesteryl ester storage in lipid droplets, and uptake of plasma lipoproteins are tuned to the cholesterol/PC ratio. Cholesterol-loaded macrophages in atherosclerotic lesions display increased PC biosynthesis that buffers against elevated cholesterol levels and may also facilitate cholesterol trafficking to enhance cholesterol sensing and efflux. These same mechanisms could play a generic role in homeostatic responses to acute changes in membrane free cholesterol levels. Here, I discuss the established and emerging roles of PC metabolism in promoting intracellular cholesterol trafficking and membrane lipid homeostasis. PMID:27081313

  12. Cholesterol Metabolism in CKD.

    PubMed

    Reiss, Allison B; Voloshyna, Iryna; De Leon, Joshua; Miyawaki, Nobuyuki; Mattana, Joseph

    2015-12-01

    Patients with chronic kidney disease (CKD) have a substantial risk of developing coronary artery disease. Traditional cardiovascular disease (CVD) risk factors such as hypertension and hyperlipidemia do not adequately explain the high prevalence of CVD in CKD. Both CVD and CKD are inflammatory states and inflammation adversely affects lipid balance. Dyslipidemia in CKD is characterized by elevated triglyceride levels and high-density lipoprotein levels that are both decreased and dysfunctional. This dysfunctional high-density lipoprotein becomes proinflammatory and loses its atheroprotective ability to promote cholesterol efflux from cells, including lipid-overloaded macrophages in the arterial wall. Elevated triglyceride levels result primarily from defective clearance. The weak association between low-density lipoprotein cholesterol level and coronary risk in CKD has led to controversy over the usefulness of statin therapy. This review examines disrupted cholesterol transport in CKD, presenting both clinical and preclinical evidence of the effect of the uremic environment on vascular lipid accumulation. Preventative and treatment strategies are explored. PMID:26337134

  13. Lipoprotein metabolism in nonalcoholic fatty liver disease

    PubMed Central

    Jiang, Zhenghui Gordon; Robson, Simon C.; Yao, Zemin

    2013-01-01

    Nonalcoholic fatty liver disease (NAFLD), an escalating health problem worldwide, covers a spectrum of pathologies characterized by fatty accumulation in hepatocytes in early stages, with potential progression to liver inflammation, fibrosis, and failure. A close, yet poorly understood link exists between NAFLD and dyslipidemia, a constellation of abnormalities in plasma lipoproteins including triglyceride-rich very low density lipoproteins. Apolipoproteins are a group of primarily liver-derived proteins found in serum lipoproteins; they not only play an extracellular role in lipid transport between vital organs through circulation, but also play an important intracellular role in hepatic lipoprotein assembly and secretion. The liver functions as the central hub for lipoprotein metabolism, as it dictates lipoprotein production and to a significant extent modulates lipoprotein clearance. Lipoprotein metabolism is an integral component of hepatocellular lipid homeostasis and is implicated in the pathogenesis, potential diagnosis, and treatment of NAFLD. PMID:23554788

  14. CC-Chemokine Ligand 2 (CCL2) Suppresses High Density Lipoprotein (HDL) Internalization and Cholesterol Efflux via CC-Chemokine Receptor 2 (CCR2) Induction and p42/44 Mitogen-activated Protein Kinase (MAPK) Activation in Human Endothelial Cells.

    PubMed

    Sun, Run-Lu; Huang, Can-Xia; Bao, Jin-Lan; Jiang, Jie-Yu; Zhang, Bo; Zhou, Shu-Xian; Cai, Wei-Bin; Wang, Hong; Wang, Jing-Feng; Zhang, Yu-Ling

    2016-09-01

    High density lipoprotein (HDL) has been proposed to be internalized and to promote reverse cholesterol transport in endothelial cells (ECs). However, the mechanism underlying these processes has not been studied. In this study, we aim to characterize HDL internalization and cholesterol efflux in ECs and regulatory mechanisms. We found mature HDL particles were reduced in patients with coronary artery disease (CAD), which was associated with an increase in CC-chemokine ligand 2 (CCL2). In cultured primary human coronary artery endothelial cells and human umbilical vein endothelial cells, we determined that CCL2 suppressed the binding (4 °C) and association (37 °C) of HDL to/with ECs and HDL cellular internalization. Furthermore, CCL2 inhibited [(3)H]cholesterol efflux to HDL/apoA1 in ECs. We further found that CCL2 induced CC-chemokine receptor 2 (CCR2) expression and siRNA-CCR2 reversed CCL2 suppression on HDL binding, association, internalization, and on cholesterol efflux in ECs. Moreover, CCL2 induced p42/44 mitogen-activated protein kinase (MAPK) phosphorylation via CCR2, and p42/44 MAPK inhibition reversed the suppression of CCL2 on HDL metabolism in ECs. Our study suggests that CCL2 was elevated in CAD patients. CCL2 suppressed HDL internalization and cholesterol efflux via CCR2 induction and p42/44 MAPK activation in ECs. CCL2 induction may contribute to impair HDL function and form atherosclerosis in CAD.

  15. CC-Chemokine Ligand 2 (CCL2) Suppresses High Density Lipoprotein (HDL) Internalization and Cholesterol Efflux via CC-Chemokine Receptor 2 (CCR2) Induction and p42/44 Mitogen-activated Protein Kinase (MAPK) Activation in Human Endothelial Cells *

    PubMed Central

    Sun, Run-Lu; Huang, Can-Xia; Bao, Jin-Lan; Jiang, Jie-Yu; Zhang, Bo; Zhou, Shu-Xian; Cai, Wei-Bin; Wang, Hong; Wang, Jing-Feng; Zhang, Yu-Ling

    2016-01-01

    High density lipoprotein (HDL) has been proposed to be internalized and to promote reverse cholesterol transport in endothelial cells (ECs). However, the mechanism underlying these processes has not been studied. In this study, we aim to characterize HDL internalization and cholesterol efflux in ECs and regulatory mechanisms. We found mature HDL particles were reduced in patients with coronary artery disease (CAD), which was associated with an increase in CC-chemokine ligand 2 (CCL2). In cultured primary human coronary artery endothelial cells and human umbilical vein endothelial cells, we determined that CCL2 suppressed the binding (4 °C) and association (37 °C) of HDL to/with ECs and HDL cellular internalization. Furthermore, CCL2 inhibited [3H]cholesterol efflux to HDL/apoA1 in ECs. We further found that CCL2 induced CC-chemokine receptor 2 (CCR2) expression and siRNA-CCR2 reversed CCL2 suppression on HDL binding, association, internalization, and on cholesterol efflux in ECs. Moreover, CCL2 induced p42/44 mitogen-activated protein kinase (MAPK) phosphorylation via CCR2, and p42/44 MAPK inhibition reversed the suppression of CCL2 on HDL metabolism in ECs. Our study suggests that CCL2 was elevated in CAD patients. CCL2 suppressed HDL internalization and cholesterol efflux via CCR2 induction and p42/44 MAPK activation in ECs. CCL2 induction may contribute to impair HDL function and form atherosclerosis in CAD. PMID:27458015

  16. About Cholesterol

    MedlinePlus

    ... High Blood Pressure Tools & Resources Stroke More About Cholesterol Updated:Aug 10,2016 It may surprise you ... our bodies to keep us healthy. What is cholesterol and where does it come from? Cholesterol is ...

  17. Low levels of high density lipoproteins in Turks, a population with elevated hepatic lipase. High density lipoprotein characterization and gender-specific effects of apolipoprotein e genotype.

    PubMed

    Mahley, R W; Pépin, J; Palaoğlu, K E; Malloy, M J; Kane, J P; Bersot, T P

    2000-08-01

    Turks have strikingly low levels of high density lipoprotein cholesterol (HDL-C) (10-15 mg/dL lower than those of Americans or Western Europeans) associated with elevated hepatic lipase mass and activity. Here we report that Turks have low levels of high density lipoprotein subclass 2 (HDL(2)), apoA-I-containing lipoproteins (LpA-I), and pre-beta-1 HDL and increased levels of HDL(3) and LpA-I/A-II particles (potentially an atherogenic lipid profile). The frequency distributions of HDL-C and LpA-I levels were skewed toward bimodality in Turkish women but were unimodal in Turkish men. The apoE genotype affected HDL-C and LpA-I levels in women only. In women, but not men, the varepsilon2 allele was strikingly more prevalent in those with the highest levels of HDL-C and LpA-I than in those with the lowest levels. The higher prevalence of the epsilon2 allele in these subgroups of women was not explained by plasma triglyceride levels, total cholesterol levels, age, or body mass index. The modulating effects of apoE isoforms on lipolytic hydrolysis of HDL by hepatic lipase (apoE2 preventing efficient hydrolysis) or on lipoprotein receptor binding (apoE2 interacting poorly with the low density lipoprotein receptors) may account for differences in HDL-C levels in Turkish women (the epsilon2 allele being associated with higher HDL levels). In Turkish men, who have substantially higher levels of hepatic lipase activity than women, the modulating effect of apoE may be overwhelmed. The gender-specific impact of the apoE genotype on HDL-C and LpA-I levels in association with elevated levels of hepatic lipase provides new insights into the metabolism of HDL.

  18. Serum Cholesterol Levels in College Students: Opportunities for Education and Intervention.

    ERIC Educational Resources Information Center

    Sparling, Phillip B.; Snow, Teresa K.; Beavers, Bill D.

    1999-01-01

    Analyzed lipid profiles in 1,088 college students at a university where lipid profiles were available to students in selected health/wellness courses. Mean total cholesterol levels were similar for men and women, but men had significantly lower high-density lipoprotein cholesterol and higher low-density lipoprotein cholesterol than women. About 11…

  19. MD-2 binds cholesterol.

    PubMed

    Choi, Soo-Ho; Kim, Jungsu; Gonen, Ayelet; Viriyakosol, Suganya; Miller, Yury I

    2016-02-19

    Cholesterol is a structural component of cellular membranes, which is transported from liver to peripheral cells in the form of cholesterol esters (CE), residing in the hydrophobic core of low-density lipoprotein. Oxidized CE (OxCE) is often found in plasma and in atherosclerotic lesions of subjects with cardiovascular disease. Our earlier studies have demonstrated that OxCE activates inflammatory responses in macrophages via toll-like receptor-4 (TLR4). Here we demonstrate that cholesterol binds to myeloid differentiation-2 (MD-2), a TLR4 ancillary molecule, which is a binding receptor for bacterial lipopolysaccharide (LPS) and is indispensable for LPS-induced TLR4 dimerization and signaling. Cholesterol binding to MD-2 was competed by LPS and by OxCE-modified BSA. Furthermore, soluble MD-2 in human plasma and MD-2 in mouse atherosclerotic lesions carried cholesterol, the finding supporting the biological significance of MD-2 cholesterol binding. These results help understand the molecular basis of TLR4 activation by OxCE and mechanisms of chronic inflammation in atherosclerosis.

  20. Effect of ezetimibe on plasma cholesterol levels, cholesterol absorption, and secretion of biliary cholesterol in laboratory opossums with high and low responses to dietary cholesterol.

    PubMed

    Chan, Jeannie; Kushwaha, Rampratap S; Vandeberg, Jane F; Vandeberg, John L

    2008-12-01

    Partially inbred lines of laboratory opossums differ in plasma low-density lipoprotein cholesterol concentration and cholesterol absorption on a high-cholesterol diet. The aim of the present studies was to determine whether ezetimibe inhibits cholesterol absorption and eliminates the differences in plasma cholesterol and hepatic cholesterol metabolism between high and low responders on a high-cholesterol diet. Initially, we determined that the optimum dose of ezetimibe was 5 mg/(kg d) and treated 6 high- and 6 low-responding opossums with this dose (with equal numbers of controls) for 3 weeks while the opossums consumed a high-cholesterol and low-fat diet. Plasma and low-density lipoprotein cholesterol concentrations decreased significantly (P < .05) in treated but not in untreated high-responding opossums. Plasma cholesterol concentrations increased slightly (P < .05) in untreated low responders but not in treated low responders. The percentage of cholesterol absorption was significantly higher in untreated high responders than in other groups. Livers from high responders with or without treatment were significantly (P < .01) heavier than livers from low responders with or without treatment. Hepatic cholesterol concentrations in untreated high responders were significantly (P < .05) higher than those in low responders with or without treatment (P < .001). The gall bladder bile cholesterol concentrations in untreated high responders were significantly (P < .05) lower than those in other groups. A decrease in biliary cholesterol in low responders treated with ezetimibe was associated with a decrease in hepatic expression of ABCG5 and ABCG8. These studies suggest that ezetimibe decreases plasma cholesterol levels in high responders mainly by decreasing cholesterol absorption and increasing biliary cholesterol concentrations. Because ezetimibe's target is NPC1L1 and NPC1L1 is expressed in the intestine of opossums, its effect on cholesterol absorption may be mediated

  1. Dietary lipids and blood cholesterol: quantitative meta-analysis of metabolic ward studies.

    PubMed Central

    Clarke, R.; Frost, C.; Collins, R.; Appleby, P.; Peto, R.

    1997-01-01

    OBJECTIVE: To determine the quantitative importance of dietary fatty acids and dietary cholesterol to blood concentrations of total, low density lipoprotein, and high density lipoprotein cholesterol. DESIGN: Meta-analysis of metabolic ward studies of solid food diets in healthy volunteers. SUBJECTS: 395 dietary experiments (median duration 1 month) among 129 groups of individuals. RESULTS: Isocaloric replacement of saturated fats by complex carbohydrates for 10% of dietary calories resulted in blood total cholesterol falling by 0.52 (SE 0.03) mmol/l and low density lipoprotein cholesterol falling by 0.36 (0.05) mmol/l. Isocaloric replacement of complex carbohydrates by polyunsaturated fats for 5% of dietary calories resulted in total cholesterol falling by a further 0.13 (0.02) mmol/l and low density lipoprotein cholesterol falling by 0.11 (0.02) mmol/l. Similar replacement of carbohydrates by monounsaturated fats produced no significant effect on total or low density lipoprotein cholesterol. Avoiding 200 mg/day dietary cholesterol further decreased blood total cholesterol by 0.13 (0.02) mmol/l and low density lipoprotein cholesterol by 0.10 (0.02) mmol/l. CONCLUSIONS: In typical British diets replacing 60% of saturated fats by other fats and avoiding 60% of dietary cholesterol would reduce blood total cholesterol by about 0.8 mmol/l (that is, by 10-15%), with four fifths of this reduction being in low density lipoprotein cholesterol. PMID:9006469

  2. [Position of lipoprotein apheresis in present].

    PubMed

    Bláha, Vladimír; Bláha, Milan; Lánská, Miriam; Havel, Eduard; Vyroubal, Pavel; Zadák, Zdeněk; Vrablík, Michal; Piťha, Jan; Žák, Pavel; Sobotka, Luboš

    2015-11-01

    Lipoprotein apheresis (LA) is an effective treatment method the patients with severe hypercholesterolemia, resistant to the standard therapy. LA is an extracorporeal elimination technique, which specifically removes low density lipoprotein (LDL) cholesterol from the circulation. At present, lipoprotein apheresis, combined with high-dose statin and ezetimibe therapy, is the best available means of treating patients with homozygous and statin refractory heterozygous familial hypercholesterolaemia (FH). However, the extent of cholesterol-lowering achieved is often insufficient to meet the targets set by current guidelines. The recent advent of new classes of lipid-lowering agents provides new hope that the latter objective may now be achievable. These compounds act either by reducing low density lipoprotein (LDL) cholesterol production by inhibiting apolipoprotein B synthesis with an antisense oligonucleotide (mipomersen), or by inhibiting microsomal triglyceride transfer protein (lomitapid), or by enhancing LDL catabolism via monoclonal antibody-mediated inhibition of the activity of proprotein convertase subtilisin/kexin 9 (PCSK9-alirocumab, evolocumab etc). The promising is the combination of LDL-apheresis with new drugs, namely for its potential to further decrease of LDL-cholesterol between apheresis. Depending on the outcome of current trials, it seems likely that these compounds, used alone or combined with lipoprotein apheresis, will markedly improve the management of refractory FH. PMID:26652784

  3. Relationship between plasma cholesterol levels and cholesterol esterification in isolated human mononuclear cells

    SciTech Connect

    Dallongeville, J.; Davignon, J.; Lussier-Cacan, S. )

    1990-01-01

    The authors studied the relationship between plasma lipoprotein concentrations and cholesterol esterification in freshly isolated human mononuclear cells from 27 normolipidemic and 32 hyperlipidemic individuals. Cells were either incubated for 5 hours with radiolabeled oleate immediately after isolation or were preincubated for 18 hours in the presence of exogenous cholesterol, and then incubated with ({sup 14}C)sodium-oleate-albumin complex. In the absence of exogenous cholesterol, control and hypercholesterolemic subjects had similarly low values of intracellular cholesterol esterification. In the presence of exogenous cholesterol, both hypertriglyceridemic and hypercholesterolemic subjects had higher cholesterol esterification than controls. There was a significant correlation between the rate of cholesterol esterification and plasma total cholesterol. These results suggest that plasma cholesterol levels may regulate mononuclear cell intra-cellular cholesterol esterification in humans.

  4. Computational studies of plasma lipoprotein lipids.

    PubMed

    Pan, Lurong; Segrest, Jere P

    2016-10-01

    Plasma lipoproteins are macromolecular assemblies of proteins and lipids found in the blood. The lipid components of lipoproteins are amphipathic lipids such as phospholipids (PLs), and unesterified cholesterols (UCs) and hydrophobic lipids such as cholesteryl esters (CEs) and triglycerides (TGs). Since lipoproteins are soft matter supramolecular assemblies easily deformable by thermal fluctuations and they also exist in varying densities and protein/lipid components, a detailed understanding of their structure/function is experimentally difficult. Molecular dynamics (MD) simulation has emerged as a particularly promising way to explore the structure and dynamics of lipoproteins. The purpose of this review is to survey the current status of computational studies of the lipid components of the lipoproteins. Computational studies aim to explore three levels of complexity for the 3-dimensional structural dynamics of lipoproteins at various metabolic stages: (i) lipoprotein particles consist of protein with minimal lipid; (ii) lipoprotein particles consist of PL-rich discoidal bilayer-like lipid particles; (iii) mature circulating lipoprotein particles consist of CE-rich or TG-rich spheroidal lipid-droplet-like particles. Due to energy barriers involved in conversion between these species, other biomolecules also participate in lipoprotein biological assembly. For example: (i) lipid-poor apolipoprotein A-I (apoA-I) interacts with ATP-binding cassette transporter A1 (ABCA1) to produce nascent discoidal high density lipoprotein (dHDL) particles; (ii) lecithin-cholesterol acyltransferase (LCAT) mediates the conversion of UC to CE in dHDL, driving spheroidal HDL (sHDL) formation; (iii) transfer proteins, cholesterol ester transfer protein (CETP) and phospholipid transfer protein (PLTP), transfer both CE and TG and PL, respectively, between lipoprotein particles. Computational studies have the potential to explore different lipoprotein particles at each metabolic stage in

  5. The serum lipoprotein pattern of water buffalo (Bubalus bubalis).

    PubMed

    Mondola, P; Santangelo, F; Santillo, M; Belfiore, A; Avallone, L; Cifaldi, S; d'Angelo, A; Pizzuti, G P

    1987-01-01

    1. The serum lipoprotein pattern of water buffalo was studied by means of electrophoresis and the lipoproteins were isolated by ultracentrifugation on the basis of their hydrated density. 2. High density lipoproteins (HDL) showed a higher level of cholesterol than did the other lipoproteins. Moreover, the level of phospholipids was higher in HDL than in very low density lipoproteins (VLDL). 3. The buffalo B100 apoprotein was similar to that of man and rat. Three apoproteins similar to human apo E, apo AI and AII were found in buffalo HDL, buffalo VLDL contained essentially apo B protein.

  6. [Basic mechanisms: structure, function and metabolism of plasma lipoproteins].

    PubMed

    Errico, Teresa L; Chen, Xiangyu; Martin Campos, Jesús M; Julve, Josep; Escolà-Gil, Joan Carles; Blanco-Vaca, Francisco

    2013-01-01

    The aim of this work is to present basic information on the lipoprotein physiology. The protein fraction of lipoproteins consists of several apolipoproteins and enzymes whose functions are lipid transport and metabolism. Classification of lipoproteins is based on their density. Chylomicrons, VLDL, IDL, LDL and HDL can be isolated by ultracentrifugation. Both chylomicrons- and VLDL-triglycerides are transported from the intestine and liver, respectively, to the peripheral tissues. The metabolism of VLDL originates IDL and LDL. LDL is the main transporter of cholesterol to extrahepatic tissues. HDL mobilizes cholesterol from peripheral tissues to the liver where it is secreted to bile as free cholesterol or bile salts, a process termed reverse cholesterol transport. Lipoprotein metabolism can be regulated by nuclear receptors that regulate the expression of genes involved in triglyceride and apolipoprotein metabolism. PMID:23769508

  7. [Basic mechanisms: structure, function and metabolism of plasma lipoproteins].

    PubMed

    Errico, Teresa L; Chen, Xiangyu; Martin Campos, Jesús M; Julve, Josep; Escolà-Gil, Joan Carles; Blanco-Vaca, Francisco

    2013-01-01

    The aim of this work is to present basic information on the lipoprotein physiology. The protein fraction of lipoproteins consists of several apolipoproteins and enzymes whose functions are lipid transport and metabolism. Classification of lipoproteins is based on their density. Chylomicrons, VLDL, IDL, LDL and HDL can be isolated by ultracentrifugation. Both chylomicrons- and VLDL-triglycerides are transported from the intestine and liver, respectively, to the peripheral tissues. The metabolism of VLDL originates IDL and LDL. LDL is the main transporter of cholesterol to extrahepatic tissues. HDL mobilizes cholesterol from peripheral tissues to the liver where it is secreted to bile as free cholesterol or bile salts, a process termed reverse cholesterol transport. Lipoprotein metabolism can be regulated by nuclear receptors that regulate the expression of genes involved in triglyceride and apolipoprotein metabolism.

  8. Metabolic abnormalities: triglyceride and low-density lipoprotein.

    PubMed

    Krauss, Ronald M; Siri, Patty W

    2004-06-01

    Increased plasma triglyceride and reduced high-density lipoprotein cholesterol are key features of the metabolic syndrome. Although elevated low-density lipoprotein cholesterol is not an integral characteristic of this syndrome, there is commonly an increase in the proportion of small, dense low-density lipoprotein particles. Together, these abnormalities constitute the atherogenic dyslipidemia of the metabolic syndrome. This article reviews the pathophysiology of altered triglyceride and low-density lipoprotein metabolism in the metabolic syndrome, outlines the relationship of these lipoprotein abnormalities to increased risk of coronary heart disease,and highlights the application of this information to clinical practice. The role of reduced high-density lipoprotein in the metabolic syndrome is discussed elsewhere in this issue.

  9. Impaired protection against diabetes and coronary heart disease by high-density lipoproteins in Turks.

    PubMed

    Onat, Altan; Can, Günay; Ayhan, Erkan; Kaya, Zekeriya; Hergenç, Gülay

    2009-10-01

    The issue of whether or not incident type 2 diabetes mellitus and coronary heart disease (CHD) can be predicted by high-density lipoprotein (HDL) cholesterol in both sexes needs investigation. A representative sample of 3035 middle-aged Turkish adults free of CHD at baseline was studied with this purpose prospectively over a mean of 7.8 years. High-density lipoprotein cholesterol levels were found to be correlated in women positively with plasma fibrinogen and weakly with waist girth and C-reactive protein, and to be not correlated with fasting insulin. High-density lipoprotein cholesterol protected men against future CHD risk (for a 12-mg/dL increment: relative risk = 0.80 [95% confidence interval, 0.69-0.95]) after multivariable adjustment in logistic regression analyses for age, smoking status, physical activity grade, hypertension, abdominal obesity, diabetes, and lipid-lowering drugs. However, men were not protected against risk of diabetes. In women, HDL cholesterol was not associated with risk for CHD, whereas intermediate (40-60 mg/dL) compared with lower HDL cholesterol levels proved protective against risk of diabetes (relative risk = 0.57 [95% confidence interval, 0.36-0.90]) after adjustments that included apolipoprotein A-I tertiles. Yet higher serum concentrations failed to yield protection against diabetes. It was concluded that HDL particles confer partially lacking protection against cardiometabolic risk among Turks, and this impairment is modulated by sex. This highly important observation may result from a setting of prevailing chronic subclinical inflammation.

  10. Unrefined and refined black raspberry seed oils significantly lower triglycerides and moderately affect cholesterol metabolism in male Syrian hamsters.

    PubMed

    Ash, Mark M; Wolford, Kate A; Carden, Trevor J; Hwang, Keum Taek; Carr, Timothy P

    2011-09-01

    Unrefined and refined black raspberry seed oils (RSOs) were examined for their lipid-modulating effects in male Syrian hamsters fed high-cholesterol (0.12% g/g), high-fat (9% g/g) diets. Hamsters fed the refined and the unrefined RSO diets had equivalently lower plasma total cholesterol and high-density lipoprotein (HDL) cholesterol in comparison with the atherogenic coconut oil diet. The unrefined RSO treatment group did not differ in liver total and esterified cholesterol from the coconut oil-fed control animals, but the refined RSO resulted in significantly elevated liver total and esterified cholesterol concentrations. The unrefined RSO diets significantly lowered plasma triglycerides (46%; P=.0126) in comparison with the coconut oil diet, whereas the refined RSO only tended to lower plasma triglyceride (29%; P=.1630). Liver triglyceride concentrations were lower in the unrefined (46%; P=.0002) and refined (36%; P=.0005) RSO-fed animals than the coconut oil group, with the unrefined RSO diet eliciting a lower concentration than the soybean oil diet. Both RSOs demonstrated a null or moderate effect on cholesterol metabolism despite enrichment in linoleic acid, significantly lowering HDL cholesterol but not non-HDL cholesterol. Dramatically, both RSOs significantly reduced hypertriglyceridemia, most likely due to enrichment in α-linolenic acid. As a terrestrial source of α-linolenic acid, black RSOs, both refined and unrefined, provide a promising alternative to fish oil supplementation in management of hypertriglyceridemia, as demonstrated in hamsters fed high levels of dietary triglyceride and cholesterol.

  11. A more flexible lipoprotein sorting pathway.

    PubMed

    Chahales, Peter; Thanassi, David G

    2015-05-01

    Lipoprotein biogenesis in Gram-negative bacteria occurs by a conserved pathway, each step of which is considered essential. In contrast to this model, LoVullo and colleagues demonstrate that the N-acyl transferase Lnt is not required in Francisella tularensis or Neisseria gonorrhoeae. This suggests the existence of a more flexible lipoprotein pathway, likely due to a modified Lol transporter complex, and raises the possibility that pathogens may regulate lipoprotein processing to modulate interactions with the host. PMID:25755190

  12. Associations of alcohol consumption with blood pressure, lipoproteins, and subclinical inflammation among Turks.

    PubMed

    Onat, Altan; Hergenc, Gülay; Dursunoglu, Dursun; Ordu, Serkan; Can, Günay; Bulur, Serkan; Yüksel, Hüsniye

    2008-11-01

    Gender-related impact of alcohol consumption on blood pressure (BP), serum lipoprotein profile, and C-reactive protein (CRP) concentrations was evaluated prospectively. Alcohol drinking status was assessed as abstainers and categories of light, moderate, and heavy (daily >40 ml ethanol) intake. Mean age of the 3,443 men and women who were followed up for a mean of 7.4 years was 47.6+/-12 years. In each multivariable linear or logistic regression analysis, alcohol drinking status was adjusted for age, sex, smoking status, and physical activity. Among men, drinking was significantly associated positively with low-density lipo protein (LDL) cholesterol, apolipoprotein (apo) B, systolic and diastolic BP, and with CRP in a log-linear manner exhibiting features of a threshold at heavy drinking. With respect to response of serum triglycerides to light-to-moderate drinking, whereas men exhibited a significant increase, women exhibited a decline (P<.05). Lower BPs (P<.03) and CRP levels (P=.032) were observed in female drinkers than abstainers and, as distinct from men, no increases in LDL cholesterol and apoB were noted. Heavy drinking tended to protect the sexes against the risk of developing low high-density lipoprotein cholesterol levels in prospective multi adjusted analyses. Sex modulates response of cardiometabolic risk variables to moderate alcohol consumption among Turks. Only women respond with lower triglycerides and CRP, whereas men show a log-linear positive association of drinking categories with BP, LDL cholesterol, apoB, and CRP.

  13. Cholesterol depletion induces autophagy

    SciTech Connect

    Cheng, Jinglei; Ohsaki, Yuki; Tauchi-Sato, Kumi; Fujita, Akikazu; Fujimoto, Toyoshi . E-mail: tfujimot@med.nagoya-u.ac.jp

    2006-12-08

    Autophagy is a mechanism to digest cells' own components, and its importance in many physiological and pathological processes is being recognized. But the molecular mechanism that regulates autophagy is not understood in detail. In the present study, we found that cholesterol depletion induces macroautophagy. The cellular cholesterol in human fibroblasts was depleted either acutely using 5 mM methyl-{beta}-cyclodextrin or 10-20 {mu}g/ml nystatin for 1 h, or metabolically by 20 {mu}M mevastatin and 200 {mu}M mevalonolactone along with 10% lipoprotein-deficient serum for 2-3 days. By any of these protocols, marked increase of LC3-II was detected by immunoblotting and by immunofluorescence microscopy, and the increase was more extensive than that caused by amino acid starvation, i.e., incubation in Hanks' solution for several hours. The induction of autophagic vacuoles by cholesterol depletion was also observed in other cell types, and the LC3-positive membranes were often seen as long tubules, >50 {mu}m in length. The increase of LC3-II by methyl-{beta}-cyclodextrin was suppressed by phosphatidylinositol 3-kinase inhibitors and was accompanied by dephosphorylation of mammalian target of rapamycin. By electron microscopy, autophagic vacuoles induced by cholesterol depletion were indistinguishable from those seen after amino acid starvation. These results demonstrate that a decrease in cholesterol activates autophagy by a phosphatidylinositol 3-kinase-dependent mechanism.

  14. Modulating the Gut Microbiota Improves Glucose Tolerance, Lipoprotein Profile and Atherosclerotic Plaque Development in ApoE-Deficient Mice

    PubMed Central

    Rune, Ida; Rolin, Bidda; Larsen, Christian; Nielsen, Dennis Sandris; Kanter, Jenny E.; Bornfeldt, Karin E.; Lykkesfeldt, Jens; Buschard, Karsten; Kirk, Rikke Kaae; Christoffersen, Berit; Fels, Johannes Josef; Josefsen, Knud; Kihl, Pernille; Hansen, Axel Kornerup

    2016-01-01

    The importance of the gut microbiota (GM) in disease development has recently received increased attention, and numerous approaches have been made to better understand this important interplay. For example, metabolites derived from the GM have been shown to promote atherosclerosis, the underlying cause of cardiovascular disease (CVD), and to increase CVD risk factors. Popular interest in the role of the intestine in a variety of disease states has now resulted in a significant proportion of individuals without coeliac disease switching to gluten-free diets. The effect of gluten-free diets on atherosclerosis and cardiovascular risk factors is largely unknown. We therefore investigated the effect of a gluten-free high-fat cholesterol-rich diet, as compared to the same diet in which the gluten peptide gliadin had been added back, on atherosclerosis and several cardiovascular risk factors in apolipoprotein E-deficient (Apoe-/-) mice. The gluten-free diet transiently altered GM composition in these mice, as compared to the gliadin-supplemented diet, but did not alter body weights, glucose tolerance, insulin levels, plasma lipids, or atherosclerosis. In parallel, other Apoe-/- mice fed the same diets were treated with ampicillin, a broad-spectrum antibiotic known to affect GM composition. Ampicillin-treatment had a marked and sustained effect on GM composition, as expected. Furthermore, although ampicillin-treated mice were slightly heavier than controls, ampicillin-treatment transiently improved glucose tolerance both in the absence or presence of gliadin, reduced plasma LDL and VLDL cholesterol levels, and reduced aortic atherosclerotic lesion area. These results demonstrate that a gluten-free diet does not seem to have beneficial effects on atherosclerosis or several CVD risk factors in this mouse model, but that sustained alteration of GM composition with a broad-spectrum antibiotic has beneficial effects on CVD risk factors and atherosclerosis. These findings

  15. Modulating the Gut Microbiota Improves Glucose Tolerance, Lipoprotein Profile and Atherosclerotic Plaque Development in ApoE-Deficient Mice.

    PubMed

    Rune, Ida; Rolin, Bidda; Larsen, Christian; Nielsen, Dennis Sandris; Kanter, Jenny E; Bornfeldt, Karin E; Lykkesfeldt, Jens; Buschard, Karsten; Kirk, Rikke Kaae; Christoffersen, Berit; Fels, Johannes Josef; Josefsen, Knud; Kihl, Pernille; Hansen, Axel Kornerup

    2016-01-01

    The importance of the gut microbiota (GM) in disease development has recently received increased attention, and numerous approaches have been made to better understand this important interplay. For example, metabolites derived from the GM have been shown to promote atherosclerosis, the underlying cause of cardiovascular disease (CVD), and to increase CVD risk factors. Popular interest in the role of the intestine in a variety of disease states has now resulted in a significant proportion of individuals without coeliac disease switching to gluten-free diets. The effect of gluten-free diets on atherosclerosis and cardiovascular risk factors is largely unknown. We therefore investigated the effect of a gluten-free high-fat cholesterol-rich diet, as compared to the same diet in which the gluten peptide gliadin had been added back, on atherosclerosis and several cardiovascular risk factors in apolipoprotein E-deficient (Apoe-/-) mice. The gluten-free diet transiently altered GM composition in these mice, as compared to the gliadin-supplemented diet, but did not alter body weights, glucose tolerance, insulin levels, plasma lipids, or atherosclerosis. In parallel, other Apoe-/- mice fed the same diets were treated with ampicillin, a broad-spectrum antibiotic known to affect GM composition. Ampicillin-treatment had a marked and sustained effect on GM composition, as expected. Furthermore, although ampicillin-treated mice were slightly heavier than controls, ampicillin-treatment transiently improved glucose tolerance both in the absence or presence of gliadin, reduced plasma LDL and VLDL cholesterol levels, and reduced aortic atherosclerotic lesion area. These results demonstrate that a gluten-free diet does not seem to have beneficial effects on atherosclerosis or several CVD risk factors in this mouse model, but that sustained alteration of GM composition with a broad-spectrum antibiotic has beneficial effects on CVD risk factors and atherosclerosis. These findings

  16. TMEM55B is a Novel Regulator of Cellular Cholesterol Metabolism

    PubMed Central

    Medina, Marisa W.; Bauzon, Frederick; Naidoo, Devesh; Theusch, Elizabeth; Stevens, Kristen; Schilde, Jessica; Schubert, Christian; Mangravite, Lara M.; Rudel, Lawrence L.; Temel, Ryan E.; Runz, Heiko; Krauss, Ronald M.

    2014-01-01

    Objective Inter-individual variation in pathways impacting cellular cholesterol metabolism can influence levels of plasma cholesterol, a well-established risk factor for cardiovascular disease. Inherent variation among immortalized lymphoblastoid cell lines (LCLs) from different donors can be leveraged to discover novel genes that modulate cellular cholesterol metabolism. The objective of this study was to identify novel genes that regulate cholesterol metabolism by testing for evidence of correlated gene expression with cellular levels of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) mRNA, a marker for cellular cholesterol homeostasis, in a large panel of LCLs. Approach and Results Expression array profiling was performed on 480 LCLs established from participants of the Cholesterol and Pharmacogenetics statin clinical trial, and transcripts were tested for evidence of correlated expression with HMGCR as a marker of intracellular cholesterol homeostasis. Of these, transmembrane protein 55b (TMEM55B) showed the strongest correlation (r=0.29, p=4.0E-08) of all genes not previously implicated in cholesterol metabolism and was found to be sterol regulated. TMEM55B knock-down in human hepatoma cell lines promoted the decay rate of the low density lipoprotein receptor (LDLR), reduced cell surface LDLR protein, impaired LDL uptake, and reduced intracellular cholesterol. Conclusions Here we report identification of TMEM55B as a novel regulator of cellular cholesterol metabolism through the combination of gene expression profiling and functional studies. The findings highlight the value of an integrated genomic approach for identifying genes that influence cholesterol homeostasis. PMID:25035345

  17. Low-density lipoprotein and noncalcified coronary plaque composition in patients with newly diagnosed coronary artery disease on computed tomographic angiography.

    PubMed

    Cheng, Victor Y; Wolak, Arik; Gutstein, Ariel; Gransar, Heidi; Wong, Nathan D; Dey, Damini; Thomson, Louise E J; Hayes, Sean W; Friedman, John D; Slomka, Piotr J; Berman, Daniel S

    2010-03-15

    We sought to determine significant relations between atherogenic lipoproteins and the contribution of calcified plaque (CP), mixed plaque (MP), and noncalcified plaque (NCP) to the total plaque (TP) burden in patients without previous coronary artery disease. From 823 adult patients without previously established coronary artery disease (52% receiving statin therapy, 34% asymptomatic) but with visible coronary plaque on coronary computed tomographic angiography, we obtained segmental CP, MP, NCP, and TP counts from contrast-enhanced, electrocardiographic-gated computed tomography. Multivariate linear regression analysis was used to determine the associations of clinical factors and lipoprotein levels to CP, MP, and NCP counts and CP/TP, MP/TP, and NCP/TP count ratios. Age, male gender, diabetes, smoking, and statin therapy were significantly associated with the CP count (p <0.001, p <0.001, p = 0.049, p = 0.016, and p = 0.003, respectively). Low-density lipoprotein (LDL) cholesterol was significantly associated with MP and NCP counts (all p values cholesterol was also the only variable to demonstrate significant concurrent relations with CP/TP, MP/TP, and NCP/TP ratios, including an inverse association with CP/TP (p = 0.008) and a positive association with MP/TP (p = 0.032). Analyses using non-high-density lipoprotein cholesterol in place of LDL cho