Pharmacologic management of isolated low high-density lipoprotein syndrome

Protective cardiovascular benefits of exercise training as measured by circulating endothelial cells and high-density lipoprotein in adults

Objective

This study aims to determine the protective cardiovascular effect of aerobic exercise training by measuring cluster of differentiation 146 (CD146), circulating endothelial cell (CEC), and high-density lipoprotein-cholesterol (HDL-C) levels in adults.

Methods

This study was an experimental pre-post-test without a control group. Forty-five participants were divided into three groups based on aerobic exercise training intensity: low, moderate, and high. Whole blood samples were measured for HDL-C levels. In addition, CEC was isolated from Peripheral Blood Mononuclear Cells (PBMC) samples, then identified by CD146 marker using flow cytometry.

Results

CEC percentage and HDL-C increase after aerobic exercise training. There was a significant difference in CEC percentage between the intensity groups. However, there was no difference in HDL-C levels.

Conclusion

Aerobic exercise training can protect cardiovascular health by stimulating CEC mobilization, identified by CD146. In addition, an HDL-C level increase also contributes to cardiovascular protection by decreasing inflammation levels, inhibiting low-density lipoprotein-cholesterol oxidation, improving endothelial regeneration capabilities, and lowering blood glucose.

Risk for Behçet's disease gauged via high-density lipoprotein cholesterol: a nationwide population-based study in Korea

Behçet’s disease (BD) is a chronic inflammatory disease. Low levels of plasma high-density lipoprotein cholesterol (HDL-C) are associated with Crohn’s disease, another chronic inflammatory disease. However, the effects of low HDL-C levels on BD are unclear. We investigated the effects of HDL-C levels, and variability therein, on the risk for BD. We used the Korean National Health Insurance System database to identify 5,587,754 adults without a history of BD who underwent ≥ 3 medical examinations between 2010 and 2013. Mean HDL-C levels at each visit were used to calculate variability independent of the mean (VIM) and the coefficient of variation (CV). There were 676 new cases of BD (0.012%). The risk for BD was increased in participants with highly variable and low mean HDL-C levels. In a multivariate-adjusted model, the hazard ratios (95% confidence intervals) for BD incidence were 1.335 (1.058–1.684) in a high mean/high VIM group, 1.527 (1.211–1.925) in a low mean/low VIM group, and 2.096 (1.67–2.63) in a low mean/high VIM group compared to a high mean/low VIM group. Low mean HDL-C levels, and high variability therein, are independent risk factors for BD.

Association of Serum High-Density Lipoprotein Cholesterol with High Blood Pressures at Checkup: Results of Kanagawa Investigation of Total Checkup Data from the National Database-9 (KITCHEN-9)

BACKGROUND

although high-density lipoprotein has cardioprotective effects, the association between serum high-density lipoprotein cholesterol (HDL-C) and hypertension is poorly understood. Therefore, we investigated whether high and low concentrations of HDL-C are associated with high blood pressure (HBP) using a large healthcare dataset.

METHODS

in a community-based cross-sectional study of 1,493,152 Japanese people (830,669 men and 662,483 women) aged 40-74 years who underwent a health checkup, blood pressures automatically measured at healthcare center were investigated in nine HDL-C groups (20-110 mg/dL or over).

RESULTS

crude U-shaped relationship were observed between the nine HDL-C and blood pressures in both men and women. Logistic regression analysis showed left-to-right inverted J-shaped relationships between HDL-C and odds ratios for HBP (≥140/90 mmHg and/or pharmacotherapy), with lower limits of 90-99 mg/dL in both sexes, which were unchanged after adjusting for confounding factors. However, further adjustment for body mass index and serum triglyceride concentration revealed positive linear associations between HDL-C and HBP, although blunt U-shaped associations remained in nonalcohol drinkers.

CONCLUSION

both low and extremely high HDL-C concentrations are associated with HBP. The former association might be dependent on excess fat mass concomitant with low HDL-C, whereas the latter association may be largely dependent on frequent alcohol consumption.

Ovarian cholesterol efflux: ATP-binding cassette transporters and follicular fluid HDL regulate cholesterol content in mouse oocytes†

High density lipoproteins (HDL) take up cholesterol from peripheral tissues via ABC transporters and deliver it to the liver via scavenger receptor class B type I (SR-B1). HDL are the main lipoproteins present in follicular fluid (FF). They are thought to derive from plasma, but their origin is still controversial. SR-B1 knock-out (KO) mice have provided important evidence linking HDL metabolism and female fertility. These mice have cholesterol-rich circulating HDL and female infertility that can be restored by treating mice with the cholesterol-lowering drug probucol. Ovulated oocytes from SR-B1 KO females are dysfunctional and show excess cholesterol. The mechanisms explaining the contribution of FF HDL to oocyte cholesterol homeostasis are unknown. Here, using quantitation of filipin fluorescence we show that in SR-B1 KO ovaries, cholesterol excess is first observed in immature oocytes in antral follicles. By performing cross-transplant experiments between WT and apolipoprotein A-I deficient (ApoA-I KO) mice, which lack the main protein component of HDL, we provide evidence supporting the plasmatic origin of FF HDL. Also, we demonstrate that probucol treatment in SR-B1 KO females results in lowering of cholesterol content in their oocytes. Incubation of oocytes from SR-B1 KO mice with purified WT HDL reduces their cholesterol content, suggesting that HDL promote efflux of excess cholesterol from oocytes. In agreement with this hypothesis, we identified ABC transporters in oocytes and observed that ABCA1 KO oocytes have excess cholesterol and lower viability than WT oocytes.

The Impact of Aerobic Exercise and Badminton on HDL Cholesterol Levels in Taiwanese Adults

Elevated levels of high-density lipoprotein cholesterol (HDL-C) have been associated with a decreased risk of coronary heart disease (CHD). An active lifestyle is necessary to improve HDL-C, including (but not limited to) physical exercise. Research on the association between badminton, an intermittent exercise, and HDL-C is limited. We investigated the impact of aerobic exercise and badminton on HDL-C levels in Taiwanese adults. The sociodemographic data of 7543 participants, comprising 3472 men and 4071 women aged between 30 and 70 years, were retrieved from the Taiwan Biobank. The participants were grouped into three exercise categories-no exercise, aerobic exercise, and badminton exercise. The HDL-C levels were compared using an analysis of variance (ANOVA). Multivariate linear regression models were used to determine the associations between HDL and exercise. Comparing the other two groups to the no-exercise group, the individuals who were engaged in aerobic and badminton exercise were significantly associated with higher HDL-C levels (β = 1.4077; p < 0.0001 and β = 5.6052; p = 0.0079, respectively). Aerobic exercise and badminton were also associated with higher HDL-C levels among carriers of the lipoprotein lipase (LPL) rs328 genotypes. Aerobic exercise and regular badminton were associated with higher levels of HDL-C, with the badminton group being more significant.

Within subject variability of HDL-cholesterol in HIV-infected patients

Background and objective: Within-subject variability of cardiovascular risk factors may influence the development of cardiovascular disease. We aimed to improve knowledge on HDL-cholesterol variability and its clinical significance in HIV-infected patients, a population at high risk of cardiovascular disease.Methods: This was a cohort study to quantify the variability of HDL-cholesterol between two consecutive visits and to determine factors associated with such variability, in a group of HIV-infected patients.Results: A total of 307 patients were included, mean ± standard deviation of their age was 45.1 ± 8.5 years, and 225 of them (73.3%) were male. The absolute difference (after squaring and root squaring) of serum HDL-cholesterol level between the first and the second visit was 12.1 ± 9.2 mg/dL. In 65 patients (21.2%) the absolute value of the difference between both serum HDL-cholesterol level results were 20 mg/dL or higher. In a multivariable analysis the number of cigarettes smoked per day showed a significant, negative, correlation with the absolute difference in serum HDL-cholesterol level between the two visits (P = 0,009).Conclusions: Within-subject variability of HDL-cholesterol was substantial among our HIV-infected patients. Smoking was inversely correlated with such variability.

Lipoproteins in Atherosclerosis Process

BACKGROUND

Dyslipidaemias is a recognized risk factor for atherosclerosis, however, new evidence brought to light by trials investigating therapies to enhance HDLcholesterol have suggested an increased atherosclerotic risk when HDL-C is high.

RESULTS

Several studies highlight the central role in atherosclerotic disease of dysfunctional lipoproteins; oxidised LDL-cholesterol is an important feature, according to "oxidation hypothesis", of atherosclerotic lesion, however, there is today a growing interest for dysfunctional HDL-cholesterol. The target of our paper is to review the functions of modified and dysfunctional lipoproteins in atherogenesis.

CONCLUSION

Taking into account the central role recognized to dysfunctional lipoproteins, measurements of functional features of lipoproteins, instead of conventional routine serum evaluation of lipoproteins, could offer a valid contribution in experimental studies as in clinical practice to stratify atherosclerotic risk.

The Impact of Aerobic Exercise and Badminton on HDL Cholesterol Levels in Adult Taiwanese

Elevated levels of high-density lipoprotein cholesterol (HDL-C) have been associated with a decreased risk of coronary heart disease (CHD). An active lifestyle is necessary in order to improve lipid HDL-C, including (but not limited to) physical exercise. Research on the association between badminton, an intermittent exercise, and HDL-C is limited. We investigated the impact of aerobic exercise and badminton on HDL-C levels in Taiwanese adults. The sociodemographic data of 7797 participants comprising 3559 men and 4238 women aged between 30 to 70 years were retrieved from the Taiwan Biobank. The participants were grouped into three exercise categories—no exercise, aerobic exercise, and badminton exercise. The HDL-C levels were compared using an analysis of variance (ANOVA). The multivariate linear regression models were used to determine the associations between HDL and exercise. Comparing the other two groups to the no-exercise group, the individuals who were engaged in aerobic and badminton exercise were significantly associated with a higher HDL-C (β =1.3154; p <0.0001 and β = 6.5954; p = 0.0027, respectively). Aerobic exercise and badminton were also associated with higher HDL-C levels among carriers of the lipoprotein lipase (LPL) rs328 genotypes. Aerobic exercise and regular badminton were associated with higher levels of HDL-C, with the badminton group being more significant.

The neurorestorative benefit of GW3965 treatment of stroke in mice

BACKGROUND AND PURPOSE

GW3965, a synthetic liver X receptor agonist, elevates high-density lipoprotein cholesterol and has antiatherosclerosis and anti-inflammation properties. We tested the hypothesis that GW3965 treatment of stroke increases vascular remodeling, promotes synaptic protein expression and axonal growth in the ischemic brain, and improves functional outcome in mice.

METHODS

Mice were subjected to transient middle cerebral artery occlusion and treated without or with different doses of GW3965 (5, 10, or 20 mg/kg) starting 24 hours after middle cerebral artery occlusion daily for 14 days. Neurological functional tests, blood high-density lipoprotein cholesterol measurement, and immunostaining were performed. Mouse brain endothelial cells, primary cultured artery explants, and primary cortical neurons cultures were also used in vitro.

RESULTS

GW3965 treatment of stroke significantly increased blood high-density lipoprotein cholesterol level, synaptic protein expression, axonal density, angiogenesis and arteriogenesis, and Angiopoietin1, Tie2, and occludin expression in the ischemic brain and improved functional outcome compared with middle cerebral artery occlusion control animals (n=10; P<0.05). In vitro, GW3965 and high-density lipoprotein cholesterol also significantly increased capillary-like tube formation and artery explant cell migration as well as neurite outgrowth. Inhibition of Angiopoietin-1 attenuated GW3965-induced tube-formation, artery cell migration, and neurite outgrowth (n=6 per group; P<0.05).

CONCLUSIONS

These data indicate, for the first time, that GW3965 promotes synaptic protein expression and axonal growth and increases vascular remodeling, which may contribute to improvement of functional outcome after stroke. Increasing Angiopoietin-1/Tie2 signaling activity may play an important role in GW3965-induced brain plasticity and neurological recovery from stroke.

The role of B vitamins in the management of heart failure

Heart failure (HF) is the leading cause of morbidity and mortality in industrialized countries, creating a significant burden on both the healthcare system and quality of life. Research efforts continue to explore new pharmaceutical or surgically based approaches to HF management, but the role of nutrition as an adjunct therapy has been largely ignored. Elderly age, anorexia, malabsorption, premature satiety, and disease severity are among the factors identified as contributing to reduced nutrient intakes in patients with HF. These factors suggest that patients with HF are at increased risk of multiple-nutrient deficiencies, including B vitamins. B vitamins may be of particular therapeutic interest because of their key roles as cofactors in energy-producing pathways. Recently, impaired stores of high-energy compounds have been linked with myocardial dysfunction and prognosis in patients with HF. Therefore, deficiencies of B vitamins might contribute to reduced energy stores and disease progression. This review summarizes the existing literature both with respect to the prevalence of B vitamin deficiency as well as evidence from supplementation trials in patients with HF. The findings suggest that most of the literature in this area has focused on thiamin deficiency in patients with HF, whereas other B vitamins remain largely unstudied. Although few sporadic trials suggest a role for B vitamins in the management of HF, none are conclusive. Therefore, there is a need for larger, more robust trials to assist in defining the B vitamin requirements as well as the impact of supplementation on both morbidity and mortality in patients with HF.

Lipid profile and nutritional intake in children and adolescents with Type 1 diabetes improve after a structured dietician training to a Mediterranean-style diet

AIM

To evaluate if nutritional intakes and lipid profile fulfill international guidelines and recommendations before and after a structured dietician training to a Mediterranean- style diet in an Italian pediatric population with Type 1 diabetes.

METHODS

A 6-month prospective cohort study. Baseline and after-intervention nutritional intakes, lipid profile, glycated hemoglobin (HbA(1c)), and clinical parameters of 96 children and adolescents with Type 1 diabetes were assessed. A comparative computerized system which was approved and validated by the Italian Diabetologist Association was used to define the amounts of nutrients.

RESULTS

At baseline mean daily dietary intakes of carbohydrates, proteins, and lipids were respectively (mean ± SEM) 51.8 ± 0.5, 15.9 ± 0.2, 33.8 ± 0.6%, with a contribution of cholesterol of 248.7 ± 12.5 mg/day. Fiber assumption was 18.0 ± 0.4 g/day. The 64.5% and 29.1% (p<0.0001) of subjects had at least one lipid parameter higher than 75(th) and 95(th) percentiles, respectively, of selected cut points (American Diabetes Association guidelines for total and LDL-cholesterol and American Academy of Pediatrics standards for HDL-cholesterol and triglycerides). Six months after the dietician intervention, dietary lipids and cholesterol decreased (p<0.0001) while fibers (p<0.0001) increased. LDL-cholesterol, non-HDL-cholesterol, and total cholesterol:HDL-cholesterol ratios significantly decreased (p<0.001) with a reduction of rate of subjects with at least one pathological lipid parameter (p<0.01) independently by weight and glucose control.

CONCLUSIONS

Italian pediatric subjects with Type 1 diabetes present a balanced diet with exception of lipids intake and a suboptimal lipid profile. A structured dietician training to a Mediterranean-style diet improves the quality of nutrient intakes being followed by a reduction of LDL-cholesterol, non- HDL-cholesterol, and total cholesterol:HDL-cholesterol ratios.

Association between HDL-C concentration and risk for a major cardiovascular event

OBJECTIVE

To determine the association between baseline HDL-C concentrations and risk of a major cardiovascular event (within 5 years) in a large US claims database.

METHODS

A retrospective longitudinal analysis using claims data from the i3 Ingenix LabRx database was conducted. Patients were included if they had complete lipid panel lab results, were continuously enrolled for >or=6 months prior to and >or=12 months following the lab test (index date), and were >or=50 years of age. Cox proportional hazards analysis assessed the association between HDL-C concentrations and risk of a major cardiovascular event within 5 years of the index date, after adjusting for covariates.

RESULTS

There was a statistically significant association between HDL-C and risk of a major cardiovascular event. A 0.026 mmol/L (1 mg/dL) increase in HDL-C from baseline was associated with a 1.3% decreased risk of a major cardiovascular event (e.g., a 0.13 mmol/L [5 mg/dL] increase in HDL-C above baseline concentrations was associated with a 6.5% decrease). This association became evident within 1 year of follow-up.

CONCLUSIONS

HDL-C concentrations were inversely associated with the occurrence of cardiovascular events within 5 years. Women who were >or=0.26 mmol/L (10 mg/dL) below their target concentrations had cardiovascular risk similar to that of women with baseline ischemic heart disease and hypertension, and men who were >or=0.26 mmol/L (10 mg/dL) below their target concentrations had cardiovascular risk similar to that of men with baseline cardiovascular disease, diabetes, or cerebrovascular disease. Limitations inherent to claims-based analyses must be considered when interpreting these findings, such as the potential for miscoding or incomplete data, and the fact that the presence of a diagnosis code on a medical claim is not positive presence of disease. Furthermore, patients who suffered a fatal cardiovascular event at home during the study period, and therefore did not receive treatment, were not captured in this analysis.

Effects of inflammation on cholesterol metabolism: impact on systemic lupus erythematosus

Inflammation and dysregulated cholesterol metabolism are key components in the pathogenesis of atherosclerosis. Premature atherosclerosis is a characteristic feature of systemic lupus erythematosus. Although the cellular and molecular mechanisms underlying accelerated atherogenesis in lupus are not thoroughly understood, inflammation associated with the rheumatic disease state may promote atherosclerosis. Increasing evidence indicates that the systemic inflammatory load in lupus disrupts cholesterol homeostasis, increasing vulnerability to cholesterol accumulation in cells of the artery wall, including macrophages and endothelium. The relationship between the inflammatory state and dyslipidemia in lupus is complex, involving lipoproteins, cholesterol transporters, scavenger receptors, and oxysterols. The impact of lupus on each of these components of the cholesterol flux pathways is discussed. The formation of autoantibodies against epitopes within lipoprotein particles and their controversial role in atherogenesis is addressed.

eNOS mediates TO90317 treatment-induced angiogenesis and functional outcome after stroke in mice

BACKGROUND AND PURPOSE

TO901317, a synthetic liver X receptor agonist, elevates high-density lipoprotein cholesterol (HDL-C) in mice. We tested the hypothesis that TO901317 treatment of stroke promotes angiogenesis and vascular maturation and improves functional outcome after stroke by increasing endothelial nitric oxide synthase (eNOS) phosphorylation.

METHODS

C57BL/6J mice were subjected to middle cerebral artery occlusion and were treated with or without TO901317 (30 mg/kg) starting 24 hours after middle cerebral artery occlusion and daily for 14 days.

RESULTS

TO901317 significantly increased serum HDL-C level, promoted angiogenesis and vascular stabilization in the ischemic brain, and improved functional outcome after stroke. The increased HDL-C level significantly correlated with functional recovery after stroke. TO901317 also increased eNOS phosphorylation in the ischemic brain. Mechanisms underlying the TO901317-induced angiogenesis were investigated using eNOS knockout (eNOS-/-) mice. TO901317 treatment of eNOS-/- mice significantly increased HDL-C level but failed to increase angiogenesis and functional outcome after stroke. In vitro studies demonstrated that TO901317 and HDL-C significantly increased capillary tube formation and promoted eNOS phosphorylation activity in cultured mouse brain endothelial cells compared with nontreatment controls. However, TO901317 and high-density lipoprotein treatment-induced capillary tube formation were absent in eNOS-deficient mouse brain endothelial cell.

CONCLUSIONS

These data indicate that TO901317 treatment increases serum HDL-C level, which promotes angiogenesis through eNOS and leads to improvement of functional outcome after stroke.