Normolipidemic Research Articles

Methylation status of LDLR, PCSK9 and LDLRAP1 is associated with cardiovascular events in familial hypercholesterolemia.

Aim: Methylation of LDLR, PCSK9 and LDLRAP1 CpG sites was assessed in patients with familial hypercholesterolemia (FH). Methods: DNA methylation of was analyzed by pyrosequencing in 131 FH patients and 23 normolipidemic (NL) subjects.Results: LDLR, PCSK9 and LDLRP1 methylation was similar between FH patients positive (MD) and negative (non-MD) for pathogenic variants in FH-related genes. LDLR and PCSK9 methylation was higher in MD and non-MD groups than NL subjects (p<0.05). LDLR, PCSK9 and LDLRAP1 methylation profiles were associated with clinical manifestations and cardiovascular events in FH patients (p<0.05).Conclusion: Differential methylation of LDLR, PCSK9 and LDLRAP1 is associated with hypercholesterolemia and cardiovascular events. This methylation profile maybe useful as a biomarker and contribute to the management of FH.

Pediatric dyslipidemia is associated with increased urinary ACE activity, blood pressure values, and carotidal-femoral pulse wave velocity.

This study aimed to evaluate the enzymatic activity of the angiotensin-converting enzyme (ACE) in children and adolescents to investigate their relationship with dyslipidemia and other cardiometabolic alterations. Anthropometric measurements, blood pressure (BP), and fasting lipid concentrations were taken from 360 subjects. Categorization was done according to the levels of each lipoprotein (total cholesterol, triglycerides (TG), LDL-C, HDL-C, and non-HDL-C) into three groups: normolipidemic (NL), borderline (BL), and dyslipidemic (DL). Enzymatic activity in urine was measured using the substrates Z-FHL-OH and hippuryl-HL-OH (h-HL-OH) and the ACE activity ratio (Z-FHL-OH/h-HL-OH) was calculated. Dyslipidemic levels of HDL-C, TG, and LDL-C were observed in 23%, 9%, and 3% of the participants, respectively, and were more frequent in obese children (Chi-square, p < 0.001). ACE activity ratio was augmented in BL(HDL-C) when compared to NL(HDL-C) (5.06 vs. 2.39, p < 0.01), in DL(LDL-C) in comparison to BL(LDL-C) and NL(LDL-C) (8.7 vs. 1.8 vs. 3.0, p < 0.01), and in DL(non-HDL-C) than in BL(non-HDL-C) and in NL(non-HDL-C) (6.3 vs. 2.1 vs. 2.9, p = 0.02). The groups with impaired HDL-C and TG levels presented an increased diastolic BP percentile, and a higher systolic BP percentile was observed in BL(TG) and DL(TG). The carotidal-femoral pulse wave velocity (cfPWV) was higher in the groups with DL levels of TG and LDL-C than in NL groups. Hypertriglyceridemia was associated with higher cfPWV. No direct impact of the ACE activity on BP values was observed in this cohort, however, there was an association between hyperlipidemia and ACE upregulation which can trigger mechanisms driving to early onset of hypertension and cardiovascular disease. Graphical abstract exemplifying the cohort, categorization of subjects into the groups NL normolipidemic, BL borderline, DL dyslipidemic, methods, and main findings. Pediatric dyslipidemia was consistent with dyslipidemia secondary to obesity (DSO), associated with higher urinary angiotensin-converting enzyme (ACE) activity ratio, BP blood pressure values, and carotidal-femoral pulse wave velocity (cfPWV).

Ameliorative Effect of Pleurotus ostreatus on Lipid Levels and Atherogenic Indices in Hyperlipidemic Rats

Aim: To evaluate the effects of Pleurotus ostreatus on the lipid profile and atherogenic indices in Hyperlipidemic rats.&#x0D; Study Design, Place and Duration of Study: This case-control study was done for 60 days between March and April, 2017 at the department of Medical Laboratory Science and Department of Chemical Pathology, Babcock University, Ogun State, Nigeria.&#x0D; Methodology: Thirty male wistar rats weighing 117-130 g were divided randomly into 3 groups: Normolipidemic (NL) rats (fed with standard rodent chow), Hyperlipidemic (HL) rats (fed with standard rodent chow + duck yolk and reused oil), Hyperlipidemic Treated (HL+T) rats (fed with standard rodent chow + duck yolk and reused oil + 5% Pleurotus ostreatus powder). &#x0D; Changes in the animal body weights were measured in this study. Serum was obtained from fasting blood samples for the standard biochemical analyses of total cholesterol (TC), triglycerides (TG), High density lipoprotein cholesterol (HDL-C), creatinine, urea, Alanine aminotransferase (ALT) and Aspartate aminotransferase (AST). Low density lipoprotein (LDL), very low density lipoprotein (VLDL), TC/HDL, LDL/HDL and Log (TG/HDL) ratios were calculated.&#x0D; Results: The HL+T rats compared to HL rats had significantly reduced body weight, TC, TG, LDL, VLDL, TC/HDL, LDL/HDL and Log(TG/HDL) by 19.59%, 14.38%, 15.82%, 25.52%, 15.83%, 28.89%, 20.24% and 27.27% respectively (p ≤ 0.05) but recorded no significant change in HDL-C (p &gt; 0.05). Creatinine, urea, AST and ALT did not show any significant change in HL rats and HL+T rats (p &gt; 0.05).&#x0D; Conclusion: Treatment of hyperlipidemic male wistar rats with Pleurotus ostreatus reduced body weight, lipid levels (TC, TG, LDL, VLDL) and atherogenic indices (TC/HDL, LDL/HDL, Log (TG/HDL)) and appeared to have no detrimental effects on the liver and kidneys. These findings may provide insights and scientific basis for the promotion of the use of Pleurotus ostreatus in controlling hyperlipidemia and associated complications.

Incidence of cardiovascular disease in familial combined hyperlipidemia: A 15-year follow-up study

Background and aimsFamilial combined hyperlipidemia (FCHL) is a complex dyslipidemia associated with premature cardiovascular disease (CVD). The present study was conducted to 1) determine the incidence of CVD in FCHL in this era of protocolled, primary prevention; and 2) examine whether cardiovascular risk estimation based on the Systemic Coronary Risk Estimation (SCORE) chart, as proposed in the 2016 ESC/EAS guidelines for the management of dyslipidemia, is justified in FCHL. MethodsFCHL patients, their normolipidemic (NL) relatives and spouses originally included in our baseline cohort in 1998–2005 (n = 596) were invited for a follow-up visit to determine the incidence of CVD, defined as (non-)fatal coronary artery disease, ischemic stroke and peripheral artery disease requiring invasive treatment. ResultsFollow-up data (median: 15 years) was acquired for 85% of the original cohort. The cumulative incidence of CVD was significantly higher in FCHL patients than in spouses (23.6% versus 4.7%; hazard ratio (HR): 5.4, 95%CI: 2.0–14.6; HR after adjustment for risk factors included in SCORE: 4.7, 95%CI: 1.6–13.8), but not in NL relatives compared to spouses (5.8% versus 4.7%). The SCORE chart tended to overestimate CVD risk in the spouses (observed [O]/expected [E] ratio:0.2, p = 0.01), but not in FCHL patients (O/E:1.3, p = 0.50). ConclusionsRisk of primary CVD is still substantially increased in FCHL patients, despite preventive measures. The overestimation of CVD risk by the SCORE chart – a nowadays frequently observed phenomenon thanks to improved primary prevention – was not seen in FCHL. These results suggest that more aggressive treatment is justified to avoid excessive CVD in FCHL.

Hyperlipidemia Alters the Pharmacokinetics of Posaconazole and Vincristine Upon Co-Administration in Rats.

ObjectivesCo-administration of posaconazole (PSZ) and vincristine (VCR) in the treatment of patients with acute lymphoblastic leukemia increases the neurotoxicity of VCR. Our aim is to study the effect of increased lipoprotein levels on the pharmacokinetics of PSZ and VCR upon co-administration in rats.MethodsRats were assigned to three groups, normolipidemic (NL), intermediate hyperlipidemic (IHL), and extreme hyperlipidemic (HL) groups. All rats were administered PSZ orally followed by VCR intravenously 4 h later. For the pharmacokinetic study, serial plasma samples were collected over 96 h and for tissue distribution study; plasma, lung, and liver tissues were collected over 48 h post oral dosing.ResultsPosaconazole showed higher plasma concentrations than VCR at all time points. Co-administration of VCR with PSZ reduced PSZ weight normalized oral clearance, increased PSZ area under the plasma concentration–time curve (AUC) from time zero to infinity, showed higher PSZ liver concentrations, and increased VCR volume of distribution of the central compartment. Upon increasing the lipoprotein levels, PSZ showed higher plasma availability and delayed tissue distribution, whereas VCR had shown a significant decrease in PSZ AUC0-24h, AUC0-tlast, and AUCo-inf (NL = IHL > HL) and a significant increase in the volume of distribution (NL = IHL < HL). Vincristine has shown higher tissue uptake and concentrations.ConclusionMonitoring cholesterol and triglyceride levels in patients with acute lymphoblastic leukemia is advisable to decrease VCR neurological side effect incidences and delay the activity of both PSZ and VCR.

Relationship between selected oxidative stress markers and lipid risk factors for cardiovascular disease in middle-aged adults and its possible clinical relevance

ObjectivesDecreased activity of HDL-associated paraoxonase 1 (PON1) and elevated levels of lipid peroxides together with abnormal lipid profile may prognosticate the progression of atherosclerosis. The aim of this study was to assess associations between selected oxidative stress markers (PON1, lipid peroxides) and lipid risk factors for cardiovascular disease in middle-aged subjects. Design and methodsArylesterase activity of PON1; lipid peroxides; total-, HDL-, LDL-, non-HDL-cholesterol; triglycerides; apolipoproteins A-I (ApoA-I) and B (ApoB), and lipid risk indexes were determined in serum of 75 volunteers (mean age 41.7±8.2years). Forty six volunteers were divided into normolipidemic (NL) and hyperlipidemic (HL) group. ResultsElevated levels of atherogenic cholesterol (LDL, non-HDL), lipid risk indexes (p<0.0001), lipid peroxides (p<0.001), and decreased activity of PON1 (p<0.05) were found in HL group. Strong correlations between PON1 activity and HDL (r=0.635, p=0.0005), apolipoprotein A-I (r=0.703, p<0.0001), ApoA-I/ApoB ratio (r=0.536, p=0.004), and non-HDL/HDL ratio (r=−0.445, p=0.013) were observed in NL group. There was no significant association between PON1 activity and these parameters in HL group. ConclusionsSignificant abnormalities of lipid parameters, oxidative stress markers and associations between PON1, HDL and apolipoprotein A-I may influence the antioxidant and anti-atherogenic functions of HDL and result in the higher susceptibility of lipoproteins to oxidative modification. Monitoring of lipid profile together with oxidative stress markers in an asymptomatic population could be beneficial for early identification of atherosclerosis-related diseases.

Cholesterol Forms and Traditional Lipid Profile for Projection of Atherogenic Dyslipidemia: Lipoprotein Subfractions and Erythrocyte Membrane Cholesterol

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.

Impaired Lipoprotein Processing in HIV Patients on Antiretroviral Therapy

Objective— HIV patients on antiretroviral therapy (HIV/ART) exhibit a unique atherogenic dyslipidemic profile with hypertriglyceridemia (HTG) and low plasma concentrations of high-density lipoprotein (HDL) cholesterol. In the Heart Positive Study of HIV/ART patients, a hypolipidemic therapy of fenofibrate, niacin, diet, and exercise reduced HTG and plasma non–HDL cholesterol concentrations and raised plasma HDL cholesterol and adiponectin concentrations. We tested the hypothesis that HIV/ART HDL have abnormal structures and properties and are dysfunctional. Approach and Results— Hypolipidemic therapy reduced the TG contents of low-density lipoprotein and HDL. At baseline, HIV/ART low-density lipoproteins were more triglyceride (TG)-rich and HDL were more TG- and cholesteryl ester-rich than the corresponding lipoproteins from normolipidemic (NL) subjects. Very-low-density lipoproteins, low-density lipoprotein, and HDL were larger than the corresponding lipoproteins from NL subjects; HIV/ART HDL were less stable than NL HDL. HDL-[ 3 H]cholesteryl ester uptake by Huh7 hepatocytes was used to assess HDL functionality. HIV/ART plasma were found to contain significantly less competitive inhibition activity for hepatocyte HDL-cholesteryl ester uptake than NL plasma were found to contain ( P &lt;0.001). Conclusions— Compared with NL subjects, lipoproteins from HIV/ART patients are larger and more neutral lipid-rich, and their HDL are less stable and less receptor-competent. On the basis of this work and previous studies of lipase activity in HIV, we present a model in which plasma lipolytic activities or hepatic cholesteryl ester uptake are impaired in HIV/ART patients. These findings provide a rationale to determine whether the distinctive lipoprotein structure, properties, and function of HIV/ART HDL predict atherosclerosis as assessed by carotid artery intimal medial thickness.

Modest diet-induced weight loss reduces macrophage cholesterol efflux to plasma of patients with metabolic syndrome.

Obesity-linked metabolic syndrome (MetS) is associated with a dyslipidemic profile that includes hypertriglyceridemia and low plasma high-density lipoprotein (HDL) cholesterol. HDL initiates reverse cholesterol transport via macrophage cholesterol efflux (MCE). Some hypothesize that dyslipidemic patients have impaired reverse cholesterol transport. MCE to patient plasma, a metric of HDL function, inversely correlates with atherosclerotic burden. Paradoxically, MCE to plasma of hypertriglyceridemic subjects is higher than that to normolipidemic (NL) plasma. Although weight loss reduces dyslipidemia, its effect on MCE to the plasma of obese patients with MetS is unknown. Thus, we tested the hypothesis that reducing dyslipidemia with weight loss reduces the MCE capacity of MetS plasma to that of NL plasma. Cholesterol efflux (MCE) from THP-1 macrophages to plasma from NL controls and to obese patients with MetS before and after weight loss was measured. MCE to plasma of obese patients with MetS was higher than that of control plasma (P = .006). Weight loss in patients with MetS (mean, -9.77 kg) reduced dyslipidemia, insulin resistance, and systolic blood pressure. HDL cholesterol was unchanged, and apolipoprotein A-I decreased with weight loss. Weight loss in patients with MetS normalized MCE (P < .001) to that of NL subjects. MCE correlated with apolipoprotein B levels (r² = 0.13-0.38). Chromatography showed that macrophage cholesterol initially associates with HDL but accumulates in apolipoprotein B-containing lipoproteins at later times. Although the initial acceptor of MCE is HDL, the elevated apolipoprotein B lipoproteins are a cholesterol sink that increases MCE in patients with MetS. Weight loss results in decreased apolipoprotein B lipoproteins and decreased MCE to plasma of patients with MetS.

Effect of Rat Serum Lipoproteins on mRNA Levels and Amiodarone Metabolism by Cultured Primary Rat Hepatocytes

Hyperlipidemia can significantly increase amiodarone (AM) in vivo liver uptake and decrease its velocity of microsomal metabolism. Here, hepatocytes isolated from normolipidemic (NL) and hyperlipidemic rats were incubated with AM in the presence or absence of diluted NL or hyperlipidemic serum. The serum was added either as preincubation before drug, or concurrently with drug; incubations without rat serum were used as controls. The hepatocyte levels of mRNA for several proteins and enzymes were also measured. Disappearance of AM was seen up to 72 h. There was little difference between hepatocytes from NL or hyperlipidemic animals in intrinsic clearance (CL(int) ) of AM. The effect of hyperlipidemic rat serum, either before or with AM, was profound, causing a significant reduction in the CL(int) . Reductions were seen in mRNA for cytochrome P450 1A1, 3A2, and 2D1, some transporters, and low-density lipoprotein receptors after exposure of hepatocytes to lipoprotein-rich sera. In conclusion, exposure of isolated hepatocytes to hyperlipidemic serum caused decreases in AM CL(int) and lower mRNA levels for some proteins involved in the uptake and metabolism of AM. When coincubated with serum, an additional effect of increased binding to lipoproteins seemed to further contribute to a reduced CL of AM.

Effect of serum lipoproteins on stereoselective halofantrine metabolism by rat hepatocytes

Experimental hyperlipidemia has shown to decrease cytochrome P450 3A4 and 2C11 expression and to increase liver concentrations and the plasma protein binding of halofantrine (HF) enantiomers. The present study examined the effect of hyperlipidemic (HL) serum on the metabolism of HF enantiomers by primary rat hepatocytes. Hepatocytes from normolipidemic (NL) and HL (poloxamer 407 treated) rats were incubated with rac-HF in cell media with or without additional rat serum (5%). In those incubations with rat serum, the hepatocytes were preincubated or coincubated with serum from NL or HL rats. Rat serum-free hepatocyte incubations served as controls. Stereospecific assays were used to measure HF and desbutylhalofantrine (its major metabolite) enantiomer concentrations in whole well contents (cells + media). Concentrations of desbutylhalofantrine were not measurable. The disappearance (apparent metabolism) of (-)-HF exceeded that of antipode, but HF metabolism did not differ between hepatocytes from NL and HL rats. Coincubation of HL rat serum with NL hepatocytes caused a significant decrease in the disappearance of (-)-HF, whereas in HL hepatocytes, a substantially decreased apparent metabolism was noted for both enantiomers. Compared with NL serum, (-)-HF disappearance was significantly lowered upon preincubation of NL hepatocytes with HL serum. A combination of factors including diminished drug metabolizing or lipoprotein receptor expression, and increased plasma protein binding in the wells, may have contributed to a decrease in apparent metabolism of the HF enantiomers in the presence of lipoproteins from HL rat serum.

Abstract P220: The Effect of Diet-Induced Weight Loss on HDL Functionality in Individuals with Metabolic Syndrome: Investigating Alteration of the Initial Step in Reverse Cholesterol Transport as a Function of Plasma Lipoprotein Composition

The prevalence of metabolic syndrome (MetS) with obesity-linked diabetes continues to increase globally and is associated with atherogenic dyslipidemia characterized by high triglycerides (TG), small, dense low-density lipoprotein cholesterol (LDL-C), and low high-density lipoprotein cholesterol (HDL-C) levels. HDL orchestrates the reverse cholesterol transport (RCT) process, initiated by macrophage cholesterol efflux (MCE). The traditional hypothesis is that individuals with dyslipidemia have impaired RCT that leads to atherogenesis. However, a recent study showed that one metric of HDL function, macrophage cholesterol efflux (MCE) to diluted patient plasma, inversely correlated with atherosclerotic burden, independent of plasma HDL-C levels. Moreover, cholesterol efflux from ABCA1-upregulated macrophage cell lines to sera of diabetic hypertriglyceridemic subjects is enhanced compared to normolipidemic (NL) controls. The effect of weight loss on MCE in obese individuals with MetS is unknown. The purpose of this study is to evaluate MCE in obese individuals with MetS as a function of plasma dyslipidemia, and to determine the effect of weight loss on the RCT process. We measured the rate of MCE from human monocytic leukemia THP1 cells to plasma of NL controls (n=24) and obese MetS (n=24) patients before and after 4 to 6 weeks of very low calorie, diet-induced weight loss. Weight loss in the MetS patients was significant, averaged 21.3 lbs, with concurrent significant decreases in TG, apoB, TC, LDL-C and non-HDL-C. Measures of insulin resistance, systolic blood pressure and kidney function improved with weight loss. HDL-C was not significantly altered, but apoA-I decreased with weight loss. MCE to plasma of obese MetS patients was higher than MCE to control plasma ((7.44 + 1.36) % vs (6.39 + 1.23) %, p=0.0069). MCE to plasma of obese MetS patients significantly decreased after weight loss (6.23 + 1.69) %, comparable to control values. MCE was strongly correlated to apoB levels (r 2 = 0.13 - 0.38), consistent with apoB lipoprotein function as a cholesterol sink. This was confirmed by size exclusion chromatography analysis of the distribution of effluxed cholesterol among plasma lipoproteins in 1 control and 2 Mets patients. In conclusion, obese patients with MetS demonstrate increased MCE, a measure of HDL function, compared to NL controls, which significantly decreases in response to diet-induced weight loss, concurrent with a reduction in triglyceride and apoB levels. These results suggest that the high apoB lipoprotein levels in MetS pateints facilitate MCE, and may at least partially compensate for the low HDL-C to promote RCT in these patients.

Apolipoprotein E mRNA expression in mononuclear cells from normolipidemic and hypercholesterolemic individuals treated with atorvastatin

BackgroundApolipoprotein E (apoE) is a key component of the lipid metabolism. Polymorphisms at the apoE gene (APOE) have been associated with cardiovascular disease, lipid levels and lipid-lowering response to statins. We evaluated the effects on APOE expression of hypercholesterolemia, APOE ε2/ε3/ε4 genotypes and atorvastatin treatment in Brazilian individuals. The relationship of APOE genotypes and plasma lipids and atorvastatin response was also tested in this population.MethodsAPOE ε2/ε3/ε4 and plasma lipids were evaluated in 181 normolipidemic (NL) and 181 hypercholesterolemic (HC) subjects. HC individuals with indication for lowering-cholesterol treatment (n = 141) were treated with atorvastatin (10 mg/day/4-weeks). APOE genotypes and APOE mRNA in peripheral blood mononuclear cells (PBMC) were analyzed by TaqMan real time PCR.ResultsHC had lower APOE expression than NL group (p < 0.05) and individuals with low APOE expression showed higher plasma total and LDL cholesterol and apoB, as well as higher apoAI (p < 0.05). Individuals carrying ε2 allele have reduced risk for hypercholesterolemia (OR: 0.27, 95% I.C.: 0.08-0.85, p < 0.05) and NL ε2 carriers had lower total and LDL cholesterol and apoB levels, and higher HDL cholesterol than non-carriers (p < 0.05). APOE genotypes did not affect APOE expression and atorvastatin response. Atorvastatin treatment do not modify APOE expression, however those individuals without LDL cholesterol goal achievement after atorvastatin treatment according to the IV Brazilian Guidelines for Dyslipidemia and Atherosclerosis Prevention had lower APOE expression than patients with desirable response after the treatment (p < 0.05).ConclusionsAPOE expression in PBMC is modulated by hypercholesterolemia and the APOE mRNA level regulates the plasma lipid profile. Moreover the expression profile is not modulated neither by atorvastatin nor APOE genotypes. In our population, APOE ε2 allele confers protection against hypercholesterolemia and a less atherogenic lipid profile. Moreover, low APOE expression after treatment of patients with poor response suggests a possible role of APOE level in atorvastatin response.

Individual Differences in Hyperlipidemia and Vitamin E Status in Response to Chronic Alcohol Self-Administration in Cynomolgus Monkeys

Chronic ethanol self-administration induces oxidative stress and exacerbates lipid peroxidation. α-Tocopherol is a potent lipid antioxidant and vitamin that is dependent upon lipoprotein transport for tissue delivery. To evaluate the extent to which vitamin E status is deranged by excessive alcohol consumption, monkeys voluntarily drinking ethanol (1.36 to 3.98 g/kg/d for 19 months, n = 11) were compared with nondrinkers (n = 5, control). Three alcohol-drinking animals developed hyperlipidemia with plasma triglyceride levels (1.8 ± 0.9 mM) double those of normolipidemic (NL) drinkers (0.6 ± 0.2) and controls (0.6 ± 0.3, p < 0.05); elevated plasma cholesterol (3.6 ± 0.5 mM) compared with NL drinkers (2.3 ± 0.2, p < 0.05) and controls (2.9 ± 0.3); and lower plasma α-tocopherol per triglycerides (14 ± 6 mmol/mol) than controls (27 ± 8) and NL drinkers (23 ± 6, p < 0.05). Hyperlipidemic monkey liver α-tocopherol (47 ± 15 nmol/g) was lower than NL drinkers (65 ± 13) and controls (70 ± 15, p = 0.080), as was adipose α-tocopherol (84 ± 37 nmol/g) compared with controls (224 ± 118) and NL drinkers (285 ± 234, p < 0.05). Plasma apolipoprotein (apo) CIII increased compared to baseline at both 12 and 19 months in the normolipidemic (p = 0.0016 and p = 0.0028, respectively) and in the hyperlipidemic drinkers (p < 0.05 and p < 0.05, respectively). Plasma apo H concentrations at 19 months were elevated hyperlipidemics (p < 0.05) relative to concentrations in control animals. C-reactive protein (CRP), a marker of inflammation, was increased compared to baseline at both the 12- and 19-month time points in the normolipidemic (p = 0.005 and p = 0.0153, respectively) and hyperlipidemic drinkers (p = 0.016 and p = 0.0201, respectively). A subset of alcohol-drinking monkeys showed a predisposition to alcohol-induced hyperlipidemia. The defect in lipid metabolism resulted in lower plasma α-tocopherol per triglycerides and depleted adipose tissue α-tocopherol, and thus decreased vitamin E status.

Orange juice decreases low-density lipoprotein cholesterol in hypercholesterolemic subjects and improves lipid transfer to high-density lipoprotein in normal and hypercholesterolemic subjects

Orange juice (OJ) is regularly consumed worldwide, but its effects on plasma lipids have rarely been explored. This study hypothesized that consumption of OJ concentrate would improve lipid levels and lipid metabolism, which are important in high-density lipoprotein (HDL) function in normolipidemic (NC) and hypercholesterolemic (HCH) subjects. Fourteen HCH and 31 NC adults consumed 750 mL/day OJ concentrate (1:6 OJ/water) for 60 days. Eight control subjects did not consume OJ for 60 days. Plasma was collected before and on the last day for biochemical analysis and an in vitro assay of transfers of radioactively labeled free-cholesterol, cholesteryl esters, phospholipids, and triglycerides from lipoprotein-like nanoemulsions to HDL. Orange juice consumption decreased low-density lipoprotein cholesterol (160 ± 17 to 141 ± 26 mg/dL, P < .01) in the HCH group but not in the NC group. HDL-cholesterol and triglycerides remained unchanged in both groups. Free-cholesterol transfer to HDL increased (HCH: 4.4 ± 2 to 5.6 ± 1%, NC: 3.2 ± 2 to 6.2 ± 1%, P< .05) whereas triglyceride (HCH 4.9 ± 1 to 3.1 ± 1%, NC 4.4 ± 1 to 3.4 ± 1%, P< .05) and phospholipid (HCH 21.6 ± 2 to 18.6 ± 3%, NC 20.2 ± 2 to 18.4 ± 2%, P < .05) transfers decreased in both groups. Cholesteryl-ester transfer decreased only in HCH (3.6 ± 1 to 3.1 ± 1%, P < .05), but not in NC. In control subjects, plasma lipids and transfers were unaltered for 60 days. Thus, by decreasing atherogenic low-density lipoprotein cholesterol in HCH and increasing HDL ability to take up free cholesterol in HCH and NC, OJ may be beneficial to both groups as free-cholesterol transfer to HDL is crucial for cholesterol esterification and reverse cholesterol transport.

Exercise training accelerates the removal from plasma of LDL-like nanoemulsion in moderately hypercholesterolemic subjects

ObjectiveExercise training improves plasma lipid profile and diminishes risk of coronary heart disease. Previously, we showed that training increases LDL plasma clearance, as tested by an artificial LDL-like nanoemulsion method, presumably by increasing LDL receptor activity. In this study, we investigated whether training could also improve LDL clearance in hypercholesterolemic subjects (HCh) that are exposed to increased risk of cardiovascular events. MethodsTwenty sedentary HCh and 20 normolipidemic (NL) sedentary volunteers were divided into four groups: 12 HCh submitted to 4-month training program, 8 HCh with no exercise program, 12 NL submitted to 4-month training and 8 NL with no exercise program. An LDL-like nanoemulsion labeled with 14C-cholesteryl ester was injected intravenously into all subjects and plasma samples were collected during 24h after injection to determine the fractional clearance rate (FCR, in h−1) by compartmental analysis. The study was performed on the first and on the last day of the 4-month study period. ResultsIn both, trained HCh and NL groups, training increased nanoemulsion FCR by 36% (0.0443±0.0126; 0.0602±0.0187, p=0.0187 and 0.0503±0.0203; 0.0686±0.0216, p=0.0827, respectively). After training, LDL cholesterol diminished in both HCh and NL groups. In HCh, but not in NL group, LDL susceptibility to oxidation decreased, but oxidized LDL was unchanged. In both non-trained groups FCR was the same for the last and the 4-month previous evaluation. ConclusionIn HCh, exercise training increased the removal of LDL as tested by the nanoemulsion, and this probably accounted for decreased LDL cholesterol and diminished LDL susceptibility to oxidation.

Influence of SCARB1 polymorphisms on serum lipids of hypercholesterolemic individuals treated with atorvastatin

The SR-BI is a key component on the cholesterol metabolism. Polymorphisms in the SR-BI gene (SCARB1) were related with variations on plasma lipoprotein profile and other risk factors for cardiovascular disease. We tested the relationship of 3 SCARB1 single nucleotide polymorphisms (SNPs) with hypercholesterolemia in a Brazilian population and whether these variants can influence lipid-lowering response to atorvastatin. c.4G>A, c.726+54C>T and c.1050C>T SNPs and serum concentrations of lipid and apolipoproteins were evaluated in 147 hypercholesterolemic (HC) and 185 normolipidemic (NL) unrelated Brazilian subjects. HC patients were treated with atorvastatin (10 mg/day/4 weeks). Frequencies of SCARB1 polymorphisms were similar between the HC and NL groups (p>0.05). The T allele for c.726+54C>T was associated with higher LDL-c in NL and with higher apoB and apoB/apoAI in HC (p<0.05). HC individuals carrying c.1050C allele carriers (CC and CT genotypes) had lower change of total cholesterol, LDL-c, apoB and apoB/apoAI ratio (p<0.05) than the TT genotype carriers in response to atorvastatin. The SCARB1 polymorphisms are related with variations in serum lipids in the Brazilian population and c.1050C>T SNP is associated with lipid-lowering atorvastatin response.

The effect of experimental hyperlipidemia on the stereoselective tissue distribution, lipoprotein association and microsomal metabolism of (±)-halofantrine

The effect of hyperlipidemia on the biodistribution of (+/-)-halofantrine (HF) was studied in rats. Plasma, adipose, and highly perfused tissues heart, lung, liver, kidney, spleen and brain were harvested for up to 48 h after dosing animals with 2 mg/kg (+/-)-HF intravenously by tail vein. Stereospecific HPLC was used to measure HF and desbutyl-HF (DHF) enantiomer concentrations. Plasma concentrations of both HF enantiomers in hyperlipidemic (HL) exceeded those in normolipidemic (NL) rats by 11- to 15-fold. Significant increases in AUC of both HF enantiomers were noted in HL spleen tissue whereas decreases were seen in HL lung and fat. In rest of the tissues either decreases or no changes were noted in HL. The concentrations of DHF were very low in NL and HL plasma but were much higher in all highly perfused tissues. Both HF and DHF enantiomers shifted from lipoprotein deficient fraction to triglyceride-rich fractions in HL plasma following in vitro incubation of the respective racemic compounds. Compared to NL, no significant differences were noted in HF metabolism to DHF in HL liver microsomes. It would appear that both reduced plasma unbound fraction and lipoprotein associated directed uptake of lipoprotein-bound drug by tissues play roles in enantiomer biodistribution.

Relación de la dieta con los niveles plasmáticos de lípidos y lipoproteínas en sujetos adultos con diferentes genotipos del gen de la apolipoproteina E

Relationship between diet and serum levels of lipids and lipoproteins in adults with different apolipoprotein E genotypes. Objective. To find a possible relationship between: usual diet, lipid profile and ApoE genotypes. Materials and methods. Assessment of lipid profile, nutritional status and body fat percentage was conducted on 150 lecturers of the Pontificia Universidad Javeriana. Other variables were: age, gender, polymorphism of the ApoE gen, health status and food consumption. Results. 76 subjects were normolipidemic (NL) and 74 were hyperlipidemic (HL). Total cholesterol (TC), LDLc and triglycerid (TG) average values (mg/dl) were 164.68‐22.57; 91.82‐23.39 and 89.45‐31.13 respectively for the NL group, and 223.67‐20.25; 145.25‐19.99 and 198.74‐49.95 respectively for the HL group. Average age was 38.4‐8.4 for NL and 39.7‐8.2 for HL; gender distribution was of 31 men and 45 women in NL, and 50 men and 24 women in the HL group. ApoE genotype frequency was similar to that reported in other populations around the world. The evaluation of energy and nutrient consumption revealed an intake higher than the overall recommendation for all the nutrients, except cholesterol in HL women. Conclusion. When correlating consumption, lipid profile and genotypes, no significant differences were found, neither in lipid nor lipoprotein levels. However, a tendency was observed in the 4/3 genotype to be prone to higher cholesterol levels compared to other genotypes, especially in the HL group.

Normolipidemic Effect of Antioxidants in Low Cholesterol-Modified Poultry EggΨ on Zn-induced Dyslipidemia and Liver Pathology in Wistar Rats

A low cholesterol (CH)-modified poultry egg (ME Psi) containing more vitamin E, lenolenic acid, and minerals Cu and Mg but low total lipid (TL) and Zn contents than the conventional egg evaluated to reduce the severity of dyslipidemia induced by excessive Zn in the diet. The experimental data was recorded on male rats fed on normolipidemic (NL) semi-synthetic basal diet containing 20 mg Zn/kg diet in control group I, Zn supplemented dyslipidemic diet-A (Zn-DL-A) and B (Zn-DL-B) containing 40 and 80 mg Zn/kg diet in groups II and III, and ME Psi-mixed Test diet-A (Zn-DL-A + 4 ME Psi) and Test diet-B (Zn-DL-B + 4 ME Psi) in groups IIEM and IIIEM, respectively, for 180 and 90 days. Data recorded on liver and blood lipid profiles showed reduction in the concentration of TL, CH, triglycerides, and glycogen (GG) in liver consequently leading to their rise in blood serum including rise in VLDL-c and LDL-c but fall in HDL-c in groups II and III rats that reversed after ME Psi treatment resulting in rise of their levels in the liver and fall in the blood of groups IIEM and IIIEM rats, respectively. Mineral status in the liver showed a rise in Zn but fall in Cu and Mg levels in groups II and III that was reversed after ME Psi treatment resulting in fall in Zn and rise in Cu and Mg concentration in the liver of groups IIEM and IIIEM rats. Hepatopathogical studies showed reduction in the dilatation of long citernal profile of endoplasmic reticulum and increase in GG and TL granules in the cytoplasm of hepatocytes of groups IIEM and IIIEM after ME Psi treatment than those of groups II and III rats. It was concluded that the inclusion of ME Psi would be helpful in reducing dyslipidemia by correcting the ionic imbalance generated by excessive Zn intake in rats or by drugs, even in chronic diseased conditions without aggravating risk factors for heart diseases in humans that need further studies.