LDL cholesterol: controversies and future therapeutic directions

Prevalence of cardiovascular disease risk factors among students of a tertiary institution in Ghana

Cardiovascular diseases (CVDs) are listed as one of the main causes of mortality and morbidity by the World Health Organization. The World Heart Federation lists overweight/obesity, blood lipid profile, and blood pressure as some of the modifiable risk factors to developing CVDs. This study sought to determine the prevalence of some of these modifiable risk factors among University of Ghana students. One hundred and twenty students were sampled for the study. Lipid profile parameters such as high-density lipoprotein (HDL), total cholesterol (TC), and total triglycerides (TG) were measured using the Vitros 5-IFS chemistry analyzer (NY, USA). The Friedewald's equation was used to determine low-density lipoprotein (LDL) levels. Anthropometric indices such as height and weight were measured following standard protocols. Body mass index (BMI) was calculated in kg/m2 using the height and weight measurements. The students were then categorized into underweight, normal, overweight, and obese according to their BMI. Blood pressure measurements were also taken. The mean age of the students was 30.04 ± 7.99 years. A total of 4.2%, 30%, and 67.5% had TG, TC, and LDL, respectively, above normal recommended ranges. Low HDL levels were observed in 32.5% of the students. About 45% had high systolic blood pressure and 32.5% with high diastolic blood pressure. In all, the risk factors studied contributed to about 95% of the variance in explaining the risk of developing CVDs. The study concludes that the cardiovascular risk factors assessed are prevalent among the students and therefore steps must be taken to address the increase in prevalence.

6-Gingerol Regulates Hepatic Cholesterol Metabolism by Up-regulation of LDLR and Cholesterol Efflux-Related Genes in HepG2 Cells

Gingerols, the pungent ingredients in ginger, are reported to possess a cholesterol-lowering activity. However, the underlying mechanism remains unclear. The present study was to investigate how 6-gingerol (6-GN), the most abundant gingerol in fresh ginger, regulates hepatic cholesterol metabolism. HepG2 cells were incubated with various concentrations of 6-GN ranging from 50 to 200 μM for 24 h. Results showed that both cellular total cholesterol and free cholesterol decreased in a dose-dependent manner. Besides, 6-GN ranging from 100 to 200 μM increased the LDLR protein and uptake of fluorescent-labeled LDL. Moreover, the mRNA and protein expressions of cholesterol metabolism-related genes were also examined. It was found that 6-GN regulated cholesterol metabolism via up-regulation of LDLR through activation of SREBP2 as well as up-regulation of cholesterol efflux-related genes LXRα and ABCA1.

Comparative Study of Serum Lipid Profiles in Nepalese Cancer Patients Attending a Tertiary Care Hospital

Significant efforts have been made to study cancer at the biochemical and cellular level and identify factors associated with progression. The aim of this hospital based randomized comparative study at the Nepalese Army Institute of Health science hospital was to assess factors in 52 people diagnosed with different types of cancer and 56 normal control persons. Fasting blood samples were analyzed for serum total cholesterol (TC), high density lipoprotein (HDL), triglycerides (TG) and low density lipoprotein (LDL). We found that biochemical parameter TC, TG, VLDL (very low density lipoprotein), LDL and HDL were significantly different in the cancer patients and healthy controls. Levels of TC, TG, LDL, HDL and VLDL were higher in the age group below 50 and that of TG was found to be higher in women than men. Our results indicate that TC, TG and HDL are increased, while LDL and VLDL are lowered in cancer patients. Our study provides clues to risk factors associated with life style, eating habits, and exercise regimens. Monitoring of these parameters with aging is recommended.

Metformin ameliorates the progression of atherosclerosis via suppressing macrophage infiltration and inflammatory responses in rabbits

AIMS

The present study aimed to investigate the possible effects of metformin on the progression of atherosclerosis in a rabbit model.

MAIN METHODS

Rabbits were randomly divided into three groups (n = 10): the control (Ctrl) group (fed with a chow diet), and two experimental groups, the AS group and the Met group (both received an atherogenic diet). After 2 weeks of acclimatization, the rabbits in the AS and Met groups were given a placebo and metformin, respectively, daily by gavage for 10 weeks. Plasma lipids and inflammatory cytokines were measured. The aorta was isolated for histological and immunohistochemical analysis. In vitro, human umbilical vein endothelial cells (HUVECs) were treated with metformin, and monocyte adhesion and adhesion molecule expression were measured.

KEY FINDINGS

Metformin reduced plasma inflammatory cytokine levels but did not alter lipid content. Compared with that in the AS group, the atherosclerosis burden in the Met group was significantly decreased. The lesional macrophage content was reduced, but the lesional collagen content was not affected in the metformin-treated rabbits, compared with the corresponding levels in the non-treated controls. Furthermore, the aortic mRNA expression levels of adhesion molecules and inflammatory cytokines in the Met group were also significantly reduced compared with those in the AS group. Metformin treatment reduced monocyte adhesion to endothelial cells (ECs) and adhesion molecule expression, and inhibited rabbit monocyte differentiation into macrophages and the macrophage inflammatory response.

SIGNIFICANCE

Our results suggest that metformin impeded the progression of atherosclerosis, possibly by suppressing macrophage infiltration and inflammatory responses.

An Integrated Lipidomics and Phenotype Study Reveals Protective Effect and Biochemical Mechanism of Traditionally Used Alisma orientale Juzepzuk in Chronic Kidney Disease

Alisma orientale Juzepzuk (AO) is widely used for various diuretic and nephropathic treatments in traditional Chinese medicines (TCM). In a clinical setting, AO is used as both a lipid-lowering and tubular interstitial fibrosis agent. However, the mechanisms of AO for the treatment of renal interstitial fibrosis and abnormal lipid metabolism are not well-understood. In this study, pharmacological and UPLC-HDMS-based lipidomic approaches were employed to investigate the lipid-lowering and tubular interstitial fibrosis effect of AO on rats with adenine-induced chronic kidney disease (CKD). Rats with CKD showed increased serum levels of creatinine and urea, tubular damage, and tubular interstitial fibrosis. Moreover, multiple lipid species were identified in CKD rats. Among these lipids, polyunsaturated fatty acid, eicosapentaenoic acid, 8,9-epoxyeicosatrienoic acid, and docosahexaenoic acid levels were significantly decreased in CKD rats compared to control rats. In CKD rats, up-regulation of the NF-κB pathway may impair polyunsaturated fatty acid metabolism, causing renal fibrosis. In addition, CKD rats showed significantly decreased diglyceride levels and increased triglyceride levels compared to the control group. Pathway over-representation analysis demonstrated that 30 metabolic pathways were associated with lipid species. AO treatment suppressed up-regulation of inflammation, and partly restored the deregulation of polyunsaturated fatty acids and glycerolipids metabolism. Our results indicated that AO treatment attenuated renal fibrosis by down-regulating inflammation, and mitigating lipid metabolism in CKD rats. In conclusion, this study has identified the therapeutic lipid-lowering and anti-fibrosis effects of AO on CKD.

Effects of monoclonal antibodies against PCSK9 on clinical cardiovascular events : A meta-analysis of randomized controlled trials

BACKGROUND

The present meta-analysis was designed to improve statistical power and review the effects of monoclonal antibodies against PCSK9 on clinical cardiovascular events.

METHODS

PubMed, Embase, Web of Science, and the Cochrane Library were searched from inception to May 2017. Studies considered to be eligible were randomized controlled trials about the effects of monoclonal antibodies against PCSK9 on clinical cardiovascular events. The primary endpoint was positively adjudicated cardiovascular events; the secondary endpoint comprised cardiac mortality, myocardial infarction (MI), coronary revascularization, stroke, and hospitalization for unstable angina.

RESULTS

We included 20 randomized controlled trials involving 67,934 patients. Monoclonal antibodies against PCSK9 were associated with a significant reduction in positively adjudicated cardiovascular events (relative risk [RR] = 0.87; 95% confidence interval [CI] = 0.81-0.93; z = 4.03; p = 0.000), MI (RR = 0.78; 95% CI = 0.71-0.86; z = 4.96; p = 0.000), coronary revascularization (RR = 0.81, 95% CI = 0.75-0.88; z = 4.93; p = 0.000), and stroke (RR = 0.76, 95% CI = 0.65-0.89; z = 3.47; p = 0.001). Monoclonal antibodies against PCSK9 did not reduce hospitalization rates due to unstable angina. The results of subgroup analysis showed that evolocumab was associated with a lower risk of positively adjudicated cardiovascular events, MI, coronary revascularization, and stroke without reducing cardiac mortality. Alirocumab reduced the incidence of cardiac mortality but not of other cardiovascular events, while bococizumab was associated with a reduced risk of stroke.

CONCLUSION

Monoclonal antibodies against PCSK9 were associated with a lower risk of positively adjudicated cardiovascular events, MI, coronary revascularization, and stroke.

miR-505-3p controls chemokine receptor up-regulation in macrophages: role in familial hypercholesterolemia

Familial hypercholesterolemia (FH) conveys a high risk of premature atherosclerosis as a result of lifelong exposure to high LDL cholesterol levels that are not fully reduced by standard-of-care lipid-lowering treatment. Inflammatory mediators have played a role in the progression of atherosclerotic lesions. Here, we investigated whether innate immunity cells in patients with FH have a specific proinflammatory phenotype that is distinct from that of cells in normal participants. To this end, miR-505-3p-a microRNA related to chronic inflammation-and its target genes were investigated in monocyte-derived macrophages (MACs) of patients with FH (FH-MACs) and non-FH controls (co-MACs). On the basis of the profiler PCR array analysis of agomiR-505-3p-transfected MACs, we identified the chemokine receptors, CCR3, CCR4, and CXCR1, as genes that are regulated by miR-505-3p via the transcription factor, RUNX1. miR-505-3p was significantly down-regulated, whereas CCR3, CCR4, CXCR, and RUNX1 were increased in FH-MAC compared with co-MAC, with the increase being more evident in the proinflammatory M1-like FH-MAC. Chemokine receptor levels were unrelated to LDL plasma levels at entry, but correlated with age in patients with FH, not in controls. In summary, we demonstrate for first time to our knowledge that MACs from FH-MACs have an inflammatory phenotype that is characterized by the up-regulation of CCR3, CCR4, and CXCR1 under the control of miR-505-3p. These results suggest a chronic inflammatory condition in FH innate immunity cells that is not reverted by standard lipid-lowering treatment.-Escate, R., Mata, P., Cepeda, J.M., Padró, T., Badimon, L. miR-505-3p controls chemokine receptor up-regulation in macrophages: role in familial hypercholesterolemia. FASEB J. 32, 601-612 (2018). www.fasebj.org.

Metabolic profiles of adipose-derived and bone marrow-derived stromal cells from elderly coronary heart disease patients by capillary liquid chromatography quadrupole time-of-flight mass spectrometry

Adipose-tissue derived mesenchymal stem cell (ADSC)-based therapy is a promising option for patients with atherosclerotic conditions, including coronary artery disease. However, the potential differences in the metabolic characteristics between bone marrow-derived mesenchymal stem cells (BMSCs) and ADSCs have remained to be fully elucidated. The present study aimed to compare the metabolic profiles of BMSCs and ADSCs via liquid chromatography quadrupole time-of-flight mass spectrometry. BMSCs and ADSCs obtained from elderly coronary heart disease patients were cultured, and after three passages, supernatants of each cell type were collected and systematically analysed. Substantial differences were detected between the metabolite signatures of ADSCs and BMSCs. In addition, further analysis using partial least-squares discriminant analysis score plots indicated significant differences between the supernatants of the two cell types. The following metabolites were deemed to be responsible for the potential differences in the metabolic characteristics of BMSCs and ADSCs: D-lactic acid, hydroxyindoleacetaldehyde, α-D-glucose, bovinic acid, 9,10-epoxyoctadecenoic acid, glyceraldehyde, phenylpyruvic acid, L-octanoylcarnitine, retinyl ester, α-ketoisovaleric acid, guanidoacetic acid, N-acetylneuraminic acid, imidazoleacetic acid riboside, sphingosine and pseudouridine 5′-phosphate. Based on these findings, there may be significant differences in the following metabolic pathways: The linoleic acid metabolic pathway, galactose metabolism, argentines and proline metabolism, retinol metabolism, glycine and serine metabolism, galactose metabolism, and amino sugar and nucleotide sugar metabolism. In conclusion, substantial differences in metabolic characteristics were detected between BMSCs and ADSCs, which may be associated with the different efficacies of atherosclerosis therapies employing these cell types.

Effects of testosterone supplementation therapy on lipid metabolism in hypogonadal men with T2DM: a meta-analysis of randomized controlled trials

Testosterone supplementation may be effective for the treatment of hypogonadism in men with type 2 diabetes mellitus (T2DM), but the evidence from randomized controlled trials (RCTs) is inconclusive. We aimed to systematically summarize results from intervention studies and assess the effects of testosterone supplementation therapy (TST) on lipid metabolism in RCTs of hypogonadal men with T2DM by meta-analysis. PubMed, Embase, and Cochrane Library databases were searched for studies reporting the effect of TST on lipid metabolism in hypogonadal men with T2DM until December 31, 2016. Seven RCTs from 252 trials, enrolling a total of 612 patients in the experimental and control groups with a mean age of 58.5 years, were included in this study. The pooled results of the meta-analysis demonstrated that TST significantly decreased TC and TG levels in hypogonadal men with T2DM compared with the control group, with mean differences (MDs) of -6.44 (95% CI: -11.82 to -1.06; I²  = 28%; p = 0.02) and -27.94 (95% CI: -52.33 to -3.54; I²  = 76%; p = 0.02). Subgroup analyses revealed that the heterogeneity (I²  = 76%) of TG originated from different economic regions, in which economic development, genetic and environmental factors, and dietary habits affect lipid metabolism of human, with a decrease (I²  = 45%) in developed countries. Additionally, subgroup analyses showed that TST increased HDL-C level in developing countries compared with the control group (MD = 2.79; 95% CI: 0.73 to 4.86; I²  = 0%; p = 0.008), but there was no improvement in developed countries (MD = 1.02; 95% CI: -4.55 to 6.60; I²  = 91%; p = 0.72). However, LDL-C levels were not improved consistently. Because the relationship between lipid metabolism and atherosclerosis is unequivocal, TST, which ameliorates lipid metabolism, may decrease the morbidity and mortality of cardiovascular disease in hypogonadal men with T2DM by preventing atherogenesis.

Effects of aerobic exercise on lipids and lipoproteins

Dyslipidemia is the risk of cardiovascular disease, and their relationship is clear. Lowering serum cholesterol can reduce the risk of coronary heart disease. At present, the main treatment is taking medicine, however, drug treatment has its limitations. Exercise not only has a positive effect on individuals with dyslipidemia, but can also help improve lipids profile. This review is intending to provide information on the effects of exercise training on both tranditional lipids, for example, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides and new lipids and lipoproteins such as non-high-density lipoprotein cholesterol, and postprandial lipoprotein. The mechanisms of aerobic exercise on lipids and lipoproteins are also briefly described.

Detection of Lipid and Amphiphilic Biomarkers for Disease Diagnostics

Rapid diagnosis is crucial to effectively treating any disease. Biological markers, or biomarkers, have been widely used to diagnose a variety of infectious and non-infectious diseases. The detection of biomarkers in patient samples can also provide valuable information regarding progression and prognosis. Interestingly, many such biomarkers are composed of lipids, and are amphiphilic in biochemistry, which leads them to be often sequestered by host carriers. Such sequestration enhances the difficulty of developing sensitive and accurate sensors for these targets. Many of the physiologically relevant molecules involved in pathogenesis and disease are indeed amphiphilic. This chemical property is likely essential for their biological function, but also makes them challenging to detect and quantify in vitro. In order to understand pathogenesis and disease progression while developing effective diagnostics, it is important to account for the biochemistry of lipid and amphiphilic biomarkers when creating novel techniques for the quantitative measurement of these targets. Here, we review techniques and methods used to detect lipid and amphiphilic biomarkers associated with disease, as well as their feasibility for use as diagnostic targets, highlighting the significance of their biochemical properties in the design and execution of laboratory and diagnostic strategies. The biochemistry of biological molecules is clearly relevant to their physiological function, and calling out the need for consideration of this feature in their study, and use as vaccine, diagnostic and therapeutic targets is the overarching motivation for this review.

Landscape of Innovation for Cardiovascular Pharmaceuticals: From Basic Science to New Molecular Entities

PURPOSE

This study examines the complete timelines of translational science for new cardiovascular therapeutics from the initiation of basic research leading to identification of new drug targets through clinical development and US Food and Drug Administration (FDA) approval of new molecular entities (NMEs) based on this research.

METHODS

This work extends previous studies by examining the association between the growth of research on drug targets and approval of NMEs associated with these targets. Drawing on research on innovation in other technology sectors, where technological maturity is an important determinant in the success or failure of new product development, an analytical model was used to characterize the growth of research related to the known targets for all 168 approved cardiovascular therapeutics.

FINDINGS

Categorizing and mapping the technological maturity of cardiovascular therapeutics reveal that (1) there has been a distinct transition from phenotypic to targeted methods for drug discovery, (2) the durations of clinical and regulatory processes were significantly influenced by changes in FDA practice, and (3) the longest phase of the translational process was the time required for technology to advance from initiation of research to a statistically defined established point of technology maturation (mean, 30.8 years).

IMPLICATIONS

This work reveals a normative association between metrics of research maturation and approval of new cardiovascular therapeutics and suggests strategies for advancing translational science by accelerating basic and applied research and improving the synchrony between the maturation of this research and drug development initiatives.

High-quality fish oil has a more favourable effect than oxidised fish oil on intermediate-density lipoprotein and LDL subclasses: a randomised controlled trial

Fish oil (FO) supplementation reduces the risk of CVD. However, it is not known if FO of different qualities have different effects on lipoprotein subclasses in humans. We aimed at investigating the effects of oxidised FO and high-quality FO supplementation on lipoprotein subclasses and their lipid concentrations in healthy humans. In all, fifty-four subjects completed a double-blind randomised controlled intervention study. The subjects were randomly assigned to receive high-quality FO (n 17), oxidised FO (n 18) or high-oleic sunflower oil capsules (HOSO, n 19) for 7 weeks. The concentration of marine n-3 fatty acids was equal in high-quality FO and oxidised FO (1·6 g EPA+DHA/d). The peroxide value (PV) and anisidine value (AV) were 4 mEq/kg and 3 in high-quality FO and HOSO, whereas the PV and AV in the oxidised FO were 18 mEq/kg and 9. Blood samples were collected at baseline and end of study. NMR spectroscopy was applied for the analysis of lipoprotein subclasses and their lipid concentrations. High-quality FO reduced the concentration of intermediate-density lipoprotein (IDL) particles and large, medium and small LDL particles, as well as the concentrations of total lipids, phospholipids, total cholesterol, cholesteryl esters and free cholesterol in IDL and LDL subclasses compared with oxidised FO and HOSO. Hence, high-quality FO and oxidised FO differently affect lipid composition in lipoprotein subclasses, with a more favourable effect mediated by high-quality FO. In future trials, reporting the oxidation levels of FO would be useful.

Triglyceride Rich Lipoprotein -LPL-VLDL Receptor and Lp(a)-VLDL Receptor Pathways for Macrophage Foam Cell Formation

Very low-density lipoprotein (VLDL) receptor is a member of the low-density lipoprotein (LDL) receptor family. It binds triglyceride rich lipoprotein (TGRL) but not LDL, because it recognizes apolipoprotein (apo)E only but not apoB. The VLDL receptor functions as a peripheral lipoprotein receptor in concert with lipoprotein lipase (LPL) in heart, muscle, adipose tissue and macrophages. In contrast to the LDL receptor, VLDL receptor binds apo E2/2 VLDL and apoE3/3 VLDL particles, and its expression is not down-regulated by intracellular lipoproteins. It has been reported that both LDL-cholesterol (LDL-C) and postprandial triglyceride (chyromicron and VLDL remnants) are risk factors for human atherosclerotic cardiovascular disease (ASCVD). True ligands such as lipoprotein particles of the VLDL receptor are chyromicron remnant (CMR) and VLDL remnant (postprandial hyperlipidemia). Although the oxidized LDL (oxLDL)-scavenger receptors pathway is considered to be the main mechanism for macrophage foam cell formation, it seems that the TGRL-LPL-VLDL receptor pathway is also involved. Since Lp(a) is one of the ligands for the VLDL receptor, the Lp(a)- VLDL receptor pathway is another potential alternative. The expression of VLDL receptor protein in mouse macrophages is modest compared to that in rabbit and human macrophages, both in vitro and in vivo. Therefore, we need to elucidate the mechanism of human ASCVD not by using the mouse model and scavenger receptors pathway but instead using the rabbit model and VLDL receptor pathway, respectively.

Different effects of bariatric surgical procedures on dyslipidemia: a registry-based analysis

BACKGROUND

The scale and variables linked to bariatric surgery's effect on dyslipidemia have not been conclusive.

OBJECTIVE

To compare the effect of Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and adjustable gastric banding (LAGB) on dyslipidemia SETTING: National bariatric surgery registry.

METHODS

Plasma lipids and associated variables were compared at baseline and 1 year (12±4 mo) after surgery for registry patients with dyslipidemia enrolled from June 2013 to August 2014.

RESULTS

The greatest mean total-cholesterol (TC) reduction was observed post-RYGB, 226.7±26.4 to 181.3±30.9 mg/dL (19.9%, n = 208), followed by post-SG, 227.9±24.4 to 206.7±34.2 mg/dL (8.9%, n = 1515; P<.001). Normal TC levels of below 200 mg/dL were achieved by 76% post-RYGB patients compared with 43.5% post-SG patients (odds ratio [OR] = 6.24, 95% confidence interval [CI]: 3.69-10.53) and 25.6% post-LABG patients (OR = 9.66, 95% CI: 4.11-22.67; P<.01). Although equivalent patterns were observed for low-density-lipoprotein cholesterol (LDL), the levels of high-density-lipoprotein cholesterol (HDL) were most improved post-SG, reaching normal levels in 58.1% of SG male patients versus 39.5% of RYGB male patients (OR = 1.56, 95% CI: 1.04-2.35), (P = .02). The lowering of triglyceride levels by approximately 75% was comparable after SG and RYGB procedures. The type of surgery was the strongest independent predictor for all lipid level improvements or remissions. Male sex was an independent predictor for LDL normalization only (OR = 1.88, 95% CI: 1.24-2.85). Excess weight loss offered no meaningful prediction for lipid improvement (OR = 1.01-1.03).

CONCLUSION

Particular types of bariatric surgeries had different effects on dyslipidemia, independent of weight loss. Overall, the RYGB achieved the biggest reduction in plasma lipids (TC and LDL), although SG did affect HDL. Our results could aid in the decision-making process regarding the most appropriate procedure for patients with dyslipidemia.

Hepatitis C virus and atherosclerosis: A legacy after virologic cure?

Hepatitis C virus (HCV) is a major pathogen with approximately 3% of the world's population (over 170 million) infected. Epidemiological studies have shown HCV is associated with an increased risk of cardiovascular and cerebrovascular mortality as well as peripheral arterial disease. This is despite HCV inducing an ostensibly favourable lipid profile with accompanying low classical risk score for atherosclerosis (AS). We discuss possible factors involved in the aetiopathogenesis of atherosclerosis in chronic HCV and hypothesise that an important mechanism underlying the development of AS is the presence of circulating low-density immune complexes that induce an inflammatory response. We suggest that HCV particles may be inducing an antibody response to lipoproteins present in the lipoviral particles and sub-viral particles - a concept similar to the more general 'autoantibody' response to modified LDL. After virologic cure some AS risk factors will recede but an increase in serum cholesterol could result in progression of early atherosclerotic lesions, leaving a legacy from persistent HCV infection that has clinical and therapeutic implications.

Saturated Fat Consumption and Risk of Coronary Heart Disease and Ischemic Stroke: A Science Update

At a workshop to update the science linking saturated fatty acid (SAFA) consumption with the risk of coronary heart disease (CHD) and ischemic stroke, invited participants presented data on the consumption and bioavailability of SAFA and their functions in the body and food technology. Epidemiological methods and outcomes were related to the association between SAFA consumption and disease events and mortality. Participants reviewed the effects of SAFA on CHD, causal risk factors, and surrogate risk markers. Higher intakes of SAFA were not associated with higher risks of CHD or stroke apparently, but studies did not take macronutrient replacement into account. Replacing SAFA by cis-polyunsaturated fatty acids was associated with significant CHD risk reduction, which was confirmed by randomized controlled trials. SAFA reduction had little direct effect on stroke risk. Cohort studies suggest that the food matrix and source of SAFA have important health effects.

Visceral adiposity and metabolic syndrome after very high-fat and low-fat isocaloric diets: a randomized controlled trial

BACKGROUND

Different aspects of dietary pattern, including macronutrient and food profiles, may affect visceral fat mass and metabolic syndrome.

OBJECTIVE

We hypothesized that consuming energy primarily from carbohydrate or fat in diets with similar food profiles would differentially affect the ability to reverse visceral adiposity and metabolic syndrome.

DESIGN

Forty-six men (aged 30-50 y) with body mass index (in kg/m²) >29 and waist circumference >98 cm were randomly assigned to a very high-fat, low-carbohydrate (VHFLC; 73% of energy fat and 10% of energy carbohydrate) or low-fat, high-carbohydrate (LFHC; 30% of energy fat and 53% of energy carbohydrate) diet for 12 wk. The diets were equal in energy (8750 kJ/d), protein (17% of energy), and food profile, emphasizing low-processed, lower-glycemic foods. Fat mass was quantified with computed tomography imaging.

RESULTS

Recorded intake of carbohydrate and total and saturated fat in the LFHC and VHFLC groups were 51% and 11% of energy, 29% and 71% of energy, and 12% and 34% of energy, respectively, with no difference in protein and polyunsaturated fatty acids. Mean energy intake decreased by 22% and 14% in the LFHC and VHFLC groups. The diets similarly reduced waist circumference (11-13 cm), abdominal subcutaneous fat mass (1650-1850 cm³), visceral fat mass (1350-1650 cm³), and total body weight (11-12 kg). Both groups improved dyslipidemia, with reduced circulating triglycerides, but showed differential responses in total and low-density lipoprotein cholesterol (decreased in LFHC group only), and high-density lipoprotein cholesterol (increased in VHFLC group only). The groups showed similar reductions in insulin, insulin C-peptide, glycated hemoglobin, and homeostasis model assessment of insulin resistance. Notably, improvements in circulating metabolic markers in the VHFLC group mainly were observed first after 8 wk, in contrast to more acute and gradual effects in the LFHC group.

CONCLUSIONS

Consuming energy primarily as carbohydrate or fat for 3 mo did not differentially influence visceral fat and metabolic syndrome in a low-processed, lower-glycemic dietary context. Our data do not support the idea that dietary fat per se promotes ectopic adiposity and cardiometabolic syndrome in humans. This study was registered at clinicaltrials.gov as NCT01750021.

Macrophage Apoptosis and Necrotic Core Development in Atherosclerosis: A Rapidly Advancing Field with Clinical Relevance to Imaging and Therapy

Cardiovascular diseases represent 1 of the main causes of death worldwide, and atherosclerosis is 1 of the major contributors leading to ischemic heart disease. Macrophages actively participate in all stages of atherosclerosis development, from plaque initiation to the transition to vulnerable plaques. Macrophage apoptosis, in particular, has been recognized as a critical step in the formation of the necrotic core, a key characteristic of unstable lesions. In this review, we discuss the role of macrophage apoptosis and clearance of apoptotic cells by efferocytosis in the development of atherosclerosis, with particular emphasis on their contribution to the development of the necrotic core and the clinical implications of this process for plaque stabilization. We consider the molecular triggers of macrophage apoptosis during atherogenesis, the role of endoplasmic reticulum (ER) stress, the roles of key cellular mediators of apoptosis and efferocytosis, and mechanisms of defective efferocytosis in the progression of atherosclerotic plaques. Finally, we discuss the important clinical implications of rapidly evolving macrophage science, such as novel approaches to imaging vulnerable atherosclerotic plaques with macrophage-sensitive positron emission tomography and magnetic resonance imaging, the role of macrophages in mediating beneficial pleiotropic actions of lipid-lowering therapies, and novel therapeutic modalities targeting ER stress, autophagy, and deficient efferocytosis. Advances in understanding the critical role of macrophages in the progression and destabilization of atherosclerosis have the potential to greatly improve the prevention and management of atherosclerotic diseases over the next decade.

Retargeting the management of hypercholesterolemia - focus on evolocumab

Hypercholesterolemia is one of the main risk factors for atherosclerosis and cardiovascular diseases. The treatment is based on the modification of the diet and lifestyle and if necessary on a pharmacological therapy. The most widely used drugs are the inhibitors of 3-hydroxy-3-methyl-glutaryl coenzyme A reductase (statins); nevertheless, many patients do not reach optimal levels of low-density lipoprotein-cholesterol (LDL-C) even with maximal dosage of statins (eventually associated to ezetimibe) or present side effects, which do not allow them to continue the treatment. Inhibitors of PCSK9 represent a new therapeutic approach for lowering LDL-C. Evolocumab and alirocumab are human monoclonal antibodies, which bind to extracellular PCSK9 and thus interfere with the degradation of low-density lipoprotein receptor. Evolocumab use is approved for the treatment of patients with heterozygous familial hypercholesterolemia (FH) and homozygous FH as an adjunct to diet and maximally tolerated statin therapy or for subjects with clinical atherosclerotic cardiovascular disease who require additional lowering of LDL-C. Phase III clinical trials have demonstrated the effectiveness of evolocumab (140 mg/every 2 weeks or 420 mg/month, via subcutaneous injection) in monotherapy and in combination with statins, in the treatment of patients intolerant to statins or with FH. In monotherapy, it reduces LDL-C by 55%, and its association with statins leads to a reduction of LDL-C by up to 63%–75%. Evolocumab has been demonstrated to be safe and well tolerated. Ongoing clinical trials are assessing the long-term effects of evolocumab on the incidence of cardiovascular risk, safety, and tolerability. This review resumes the available clinical evidence on the efficacy and safety of evolocumab, for which a relatively large amount of clinical data are currently available, and discusses the retargeting of cholesterol-lowering therapy in clinical practice.

Integrating diet and exercise into care of prostate cancer patients on androgen deprivation therapy

Improved diagnosis and treatment regimens have resulted in greater longevity for men with prostate cancer. This has led to an increase in both androgen deprivation therapy (ADT) use and duration of exposure, and therefore to its associated adverse effects, such as sexual dysfunction, osteoporosis, reduced muscle mass, increased fat mass, and increased incidence of cardiovascular disease and type 2 diabetes. Given that the adverse effects of ADT are systemic, often debilitating, and difficult to treat, efforts continue in the development of new strategies for long-term management of prostate cancer. The PubMed database was searched to select trials, reviews, and meta-analyses in English using such search terms as "prostate cancer" and "androgen deprivation therapy", "cardiovascular risk", "lean body mass", "exercise", and "diet". The initial searches produced 379 articles with dates 2005 or more recent. Articles published after 2004 were favored. This review utilizes the latest data to provide a status update on the effects of exercise and diet on patients with prostate cancer, focusing on ADT-associated side effects, and it discusses the evidence for such interventions. Since the evidence of large-scale trials in patients with prostate cancer is missing, and an extrapolation of supporting data to all patient subgroups cannot be provided, individualized risk assessments remain necessary before the initiation of exercise and diet programs. Exercise, diet, and nutritional supplementation interventions have the potential to provide effective, accessible, and relatively inexpensive strategies for mitigating ADT-associated toxicities without introducing additional adverse effects.

Metabolomic Profiling of Statin Use and Genetic Inhibition of HMG-CoA Reductase

Background

Statins are first-line therapy for cardiovascular disease prevention, but their systemic effects across lipoprotein subclasses, fatty acids, and circulating metabolites remain incompletely characterized.

Objectives

This study sought to determine the molecular effects of statin therapy on multiple metabolic pathways.

Methods

Metabolic profiles based on serum nuclear magnetic resonance metabolomics were quantified at 2 time points in 4 population-based cohorts from the United Kingdom and Finland (N = 5,590; 2.5 to 23.0 years of follow-up). Concentration changes in 80 lipid and metabolite measures during follow-up were compared between 716 individuals who started statin therapy and 4,874 persistent nonusers. To further understand the pharmacological effects of statins, we used Mendelian randomization to assess associations of a genetic variant known to mimic inhibition of HMG-CoA reductase (the intended drug target) with the same lipids and metabolites for 27,914 individuals from 8 population-based cohorts.

Results

Starting statin therapy was associated with numerous lipoprotein and fatty acid changes, including substantial lowering of remnant cholesterol (80% relative to low-density lipoprotein cholesterol [LDL-C]), but only modest lowering of triglycerides (25% relative to LDL-C). Among fatty acids, omega-6 levels decreased the most (68% relative to LDL-C); other fatty acids were only modestly affected. No robust changes were observed for circulating amino acids, ketones, or glycolysis-related metabolites. The intricate metabolic changes associated with statin use closely matched the association pattern with rs12916 in the HMGCR gene (R² = 0.94, slope 1.00 ± 0.03).

Conclusions

Statin use leads to extensive lipid changes beyond LDL-C and appears efficacious for lowering remnant cholesterol. Metabolomic profiling, however, suggested minimal effects on amino acids. The results exemplify how detailed metabolic characterization of genetic proxies for drug targets can inform indications, pleiotropic effects, and pharmacological mechanisms.

Implications of thermogenic adipose tissues for metabolic health

Excess and ectopic fat accumulation in obesity is a major risk factor for developing hyperlipidemia, type 2 diabetes and cardiovascular disease. The activation of brown and/or beige adipocytes is a promising target for the treatment of metabolic disorders as the combustion of excess energy by these thermogenic adipocytes may help losing weight and improving plasma parameters including triglyceride, cholesterol and glucose levels. The regulation of heat production by thermogenic adipose tissues is based on a complex crosstalk between the autonomous nervous system, intracellular and secreted factors. This multifaceted alignment regulates thermogenic demands to environmental circumstances in dependence on available energy resources. This review summarizes the current knowledge how thermogenic tissues can be targeted to combat the burden of diseases with a special focus on lipid metabolism and diseases related to lipoprotein metabolism.

The effects of a nutraceutical combination on plasma lipids and glucose: A systematic review and meta-analysis of randomized controlled trials

Dyslipidemia and hyperglycemia are associated with an increased risk of ischemic cardiovascular disease. Positive effects of a nutraceutical combination comprising red yeast rice, berberine, policosanol, astaxanthin, coenzyme Q10 and folic acid (NComb) on plasma lipid and glucose levels have been reported in some but not all clinical trials. To address this inconsistency, we tried to estimate the size of lipid- and glucose-lowering effects of NComb through a systematic review and meta-analysis of randomized controlled trials. A systematic literature search in PubMed-Medline, SCOPUS and Google Scholar databases was conducted to identify randomized controlled trials investigating the effects of NComb on plasma lipids and glucose levels. Inverse variance-weighted mean differences (WMDs) and 95% confidence intervals (CIs) were calculated for net changes in lipid and glucose levels using a random-effects model. Random-effects meta-regression was performed to assess the effect of putative confounders on plasma lipid and glucose levels. Fourteen trials (1670 subjects in the NComb arm and 1489 subjects in the control arm) met the eligibility criteria for lipid analysis and 10 trials (1014 subjects in the NComb arm and 962 subjects in the control arm) for glucose analysis. Overall, WMDs were significant for the impact of NComb supplementation on plasma levels of total cholesterol (-26.15mg/dL, p<0.001), LDL-cholesterol (-23.85mg/dL, p<0.001), HDL-cholesterol (2.53mg/dL, p<0.001), triglycerides (-13.83mg/dL, p<0.001) and glucose (-2.59mg/dL, p=0.010). NComb-induced amelioration of lipid profile was not affected by duration of supplementation nor by baseline lipid levels; conversely, a greater glucose-lowering effect of NComb was found with higher baseline glucose levels and longer durations of supplementation. In conclusion, the present results suggest that NComb supplementation is associated with improvement of lipid and glucose profile. Short-term beneficial effects of NComb supplementation appear to be maintained in the long term.

Evaluating bococizumab, a monoclonal antibody to PCSK9, on lipid levels and clinical events in broad patient groups with and without prior cardiovascular events: Rationale and design of the Studies of PCSK9 Inhibition and the Reduction of vascular Events (SPIRE) Lipid Lowering and SPIRE Cardiovascular Outcomes Trials

BACKGROUND

Although statins significantly reduce vascular event rates, residual cholesterol risk remains high in many patient groups, including those with known vascular disease as well as in the setting of high-risk primary prevention. Bococizumab is a humanized monoclonal antibody that inhibits proprotein convertase subtilisin-kexin type 9 (PCSK9), prolongs the half-life of hepatic low-density lipoprotein (LDL) receptors, and reduces circulating atherogenic cholesterol levels.

DESIGN

The SPIRE program comprises 6 lipid-lowering studies and 2 cardiovascular outcomes trials, each comparing bococizumab (150 mg subcutaneously every 2 weeks) to matching placebo. The 6 SPIRE lipid-lowering studies include 3 parallel 12-month assessments of bococizumab on atherogenic lipids among statin-treated individuals at high residual risk (SPIRE-HR, SPIRE-LDL, SPIRE-LL), one 12-month study of bococizumab among individuals with familial hypercholesterolemia (SPIRE-FH), one 6-month study of bococizumab among those with statin intolerance (SPIRE-SI), and one 3-month study of bococizumab delivery using an auto-injector device (SPIRE-AI). The SPIRE-1 and SPIRE-2 event-driven cardiovascular outcome trials will assess the efficacy and safety of bococizumab in the prevention of incident vascular events in high-risk populations with and without clinically evident cardiovascular disease who have directly measured entry LDL cholesterol levels ≥70 mg/dL (SPIRE-1, n = 17,000) or ≥100 mg/dL (SPIRE-2, n = 11,000).

SUMMARY

The SPIRE trials, inclusive of more than 30,000 participants worldwide, will ascertain the magnitude of reduction in atherogenic lipids that accrue with bococizumab and determine whether the addition of this PCSK9 inhibitor to standard treatment significantly reduces cardiovascular morbidity and mortality in high-risk patients, including those without a history of clinical cardiovascular events.

Adipose-Derived Mesenchymal Stem Cells Ameliorate Lipid Metabolic Disturbance in Mice

: Adipose-derived mesenchymal stem cells (AD-MSCs) have been shown to ameliorate hyperglycemia in diabetic animals and individuals. However, little is known about whether AD-MSCs affect lipid metabolism. Here we have demonstrated for the first time that AD-MSC infusion can significantly suppress the increase in body weight and remarkably improve dyslipidemia in db/db obese mice and diet-induced obesity mice. Induction of white fat tissue "browning" and activation of adenosine monophosphate-activated protein kinase and its downstream hormone-sensitive lipase in adipose tissue contribute to the antiobesity and lipid-lowering effects. Thus, AD-MSC infusion holds great therapeutic potential for dyslipidemia and associated cardiovascular diseases.

SIGNIFICANCE

Mesenchymal stem cells (MSCs) are considered one of the most promising types of stem cells for translational application because of their rich tissue sources, multilineage differentiation capacity, and easy amplification in vitro and unique immunobiological properties. This study demonstrated that adipose-derived MSCs (AD-MSCs) infusion can significantly suppress the increase in body weight and remarkably improve dyslipidemia in obese mice. Induction of white fat tissue "browning" and activation of adenosine monophosphate-activated protein kinase and its downstream hormone-sensitive lipase in adipose tissue were demonstrated to contribute to the antiobesity and lipid-lowering effects. Thus, AD-MSC infusion holds great therapeutic potential for dyslipidemia.

Cardiovascular risk in rheumatoid arthritis: assessment, management and next steps

Rheumatoid arthritis (RA) is associated with increased cardiovascular (CV) morbidity and mortality which cannot be fully explained by traditional CV risk factors; cumulative inflammatory burden and antirheumatic medication-related cardiotoxicity seem to be important contributors. Despite the acknowledgment and appreciation of CV disease burden in RA, optimal management of individuals with RA represents a challenging task which remains suboptimal. To address this need, the European League Against Rheumatism (EULAR) published recommendations suggesting the adaptation of traditional risk scores by using a multiplication factor of 1.5 if two of three specific criteria are fulfilled. Such guidance requires proper coordination of several medical specialties, including general practitioners, rheumatologists, cardiologists, exercise physiologists and psychologists to achieve a desirable result. Tight control of disease activity, management of traditional risk factors and lifestyle modification represent, amongst others, the most important steps in improving CV disease outcomes in RA patients. Rather than enumerating studies and guidelines, this review attempts to critically appraise current literature, highlighting future perspectives of CV risk management in RA.

Current Treatment of Dyslipidemia: Evolving Roles of Non-Statin and Newer Drugs

Since their introduction, statin (HMG-CoA reductase inhibitor) drugs have advanced the practice of cardiology to unparalleled levels. Even so, coronary heart disease (CHD) still remains the leading cause of death in developed countries, and is predicted to soon dominate the causes of global mortality and disability as well. The currently available non-statin drugs have had limited success in reversing the burden of heart disease, but new information suggests they have roles in sizeable subpopulations of those affected. In this review, the status of approved non-statin drugs and the significant potential of newer drugs are discussed. Several different ways to raise plasma high-density lipoprotein (HDL) cholesterol (HDL-C) levels have been proposed, but disappointments are now in large part attributed to a preoccupation with HDL quantity, rather than quality, which is more important in cardiovascular (CV) protection. Niacin, an old drug with many antiatherogenic properties, was re-evaluated in two imperfect randomized controlled trials (RCTs), and failed to demonstrate clear effectiveness or safety. Fibrates, also with an attractive antiatherosclerotic profile and classically used for hypertriglyceridemia, lacks evidence-based proof of efficacy, save for a subgroup of diabetic patients with atherogenic dyslipidemia. Omega-3 fatty acids fall into this category as well, even with an impressive epidemiological evidence base. Omega-3 research has been plagued with methodological difficulties yielding tepid, uncertain, and conflicting results; well-designed studies over longer periods of time are needed. Addition of ezetimibe to statin therapy has now been shown to decrease levels of low-density lipoprotein (LDL) cholesterol (LDL-C), accompanied by a modest decrease in the number of CV events, though without any improvement in CV mortality. Importantly, the latest data provide crucial evidence that LDL lowering is central to the management of CV disease. Of drugs that inhibit cholesteryl ester transfer protein (CETP) tested thus far, two have failed and two remain under investigation and may yet prove to be valuable therapeutic agents. Monoclonal antibodies to proprotein convertase subtilisin/kexin type 9, now in phase III trials, lower LDL-C by over 50 % and are most promising. These drugs offer new ability to lower LDL-C in patients in whom statin drug use is, for one reason or another, limited or insufficient. Mipomersen and lomitapide have been approved for use in patients with familial hypercholesterolemia, a more common disease than appreciated. Anti-inflammatory drugs are finally receiving due attention in trials to elucidate potential clinical usefulness. All told, even though statins remain the standard of care, non-statin drugs are poised to assume a new, vital role in managing dyslipidemia.

Endocytic adaptors Arh and Dab2 control homeostasis of circulatory cholesterol

High serum cholesterol (hypercholesterolemia) strongly associates with cardiovascular diseases as the atherogenic LDLs promote atheroma development in arteries (atherosclerosis). LDL clearance from the circulation by LDL receptor (LDLR)-mediated endocytosis by hepatic and peripheral tissues and subsequent feedback regulation of endogenous synthesis of cholesterol is a key determinant of serum LDL level. Human mutation analysis revealed that autosomal recessive hypercholesterolemia (ARH), an LDLR endocytic adaptor, perturbs LDLR function and thus impacts serum cholesterol levels. In our genetic analysis of mutant mice, we found that deletion of another LDLR endocytic adaptor, Disabled-2 (Dab2), only slightly affected serum cholesterol levels. However, elimination of both arh and dab2 genes in mice resulted in profound hypercholesterolemia similar to that resulting from ldlr homozygous deletion. In the liver, Dab2 is expressed in sinusoid endothelial cells but not in hepatocytes. When deleting both Dab2 and Arh, HMG-CoA reductase level increased to the level similar to that of ldlr knockout. Thus, in the absence of Arh, Dab2 in liver endothelial cells regulates cholesterol synthesis in hepatocytes. We conclude that the combination of Arh and Dab2 is responsible for the majority of adaptor function in LDLR endocytosis and LDLR-mediated cholesterol homeostasis.

Are Genetic Tests for Atherosclerosis Ready for Routine Clinical Use?

In this review, we lay out 3 areas currently being evaluated for incorporation of genetic information into clinical practice related to atherosclerosis. The first, familial hypercholesterolemia, is the clearest case for utility of genetic testing in diagnosis and potentially guiding treatment. Already in use for confirmatory testing of familial hypercholesterolemia and for cascade screening of relatives, genetic testing is likely to expand to help establish diagnoses and facilitate research related to most effective therapies, including new agents, such as PCSK9 inhibitors. The second area, adding genetic information to cardiovascular risk prediction for primary prevention, is not currently recommended. Although identification of additional variants may add substantially to prediction in the future, combining known variants has not yet demonstrated sufficient improvement in prediction for incorporation into commonly used risk scores. The third area, pharmacogenetics, has utility for some therapies today. Future utility for pharmacogenetics will wax or wane depending on the nature of available drugs and therapeutic strategies.

Statin therapy across the lifespan: evidence in major age groups

This review provides needed perspective on statin efficacy and safety in individuals under 40, 40-75, and > 75 years of age. Starting with the 2013 ACC-AHA cholesterol guidelines extensive evidence base on randomized controlled trials (RCTs) we added references in the past 5 years that discussed statin efficacy and safety over the life span. In those under 40, statins are primarily used for treatment of severe hypercholesterolemia, often familial, and they are well tolerated. In middle-aged adults, statins have strong evidence for benefit in primary and secondary prevention trials; however, in primary prevention, a clinician-patient risk discussion should precede statin prescription in order to determine appropriate treatment. In those over 75, issues of statin intensity and net benefit loom large as associated comorbidity, polypharmacy, and potential for adverse effects impact the decision to use statins with RCT data strongest in support of use in secondary prevention. Statin drugs have been studied by RCTs in a large number of individuals. In those groups shown to benefit, statins have reduced the risk of atherosclerotic cardiovascular disease with few side effects as compared to controls. This review has detailed considerations that should occur when statins are given to individuals in different age groups.

Subcutaneous fat mass in infancy and cardiovascular risk factors at school-age: The generation R study

OBJECTIVE

To examine the associations of infant subcutaneous fat with cardiovascular risk factors at school-age.

METHODS

In a population-based prospective cohort study among 808 children, total subcutaneous fat (sum of biceps, triceps, suprailiacal, and subscapular skinfold thicknesses) and central-to-total subcutaneous fat ratio (sum of suprailiacal and subscapular skinfold thicknesses/total subcutaneous fat) at 1.5 and 24 months were estimated. At 6 years, body mass index, blood pressure, cholesterol, triglycerides, and insulin levels were measured.

RESULTS

Infant subcutaneous fat measures were not associated with childhood blood pressure, triglycerides, or insulin levels. A 1-standard-deviation score (SDS) higher total subcutaneous fat at 1.5 months was, independently of body mass index, associated with lower low-density lipoprotein (LDL)-cholesterol levels at 6 years. In contrast, a 1-SDS higher total subcutaneous fat at 24 months was associated with higher total-cholesterol [difference 0.13 (95% confidence interval (CI) 0.03, 0.23) SDS] and LDL-cholesterol levels [difference 0.12 (95% CI 0.02, 0.21) SDS] at 6 years. There were no associations of central-to-total subcutaneous fat ratio with childhood cholesterol levels.

CONCLUSIONS

These results suggest that infant total subcutaneous fat is weakly associated with cholesterol levels at school-age. Further studies are needed to assess the long-term cardiometabolic consequences of infant body fat.

Antilipidemic Drug Therapy Today and in the Future

The armamentarium for the treatment of dyslipidemia today comprises six different modes of action with overall around 24 different drugs. The treatment of lipid disorders was revolutionized with the introduction of statins which have become the most important therapeutic option available today to reduce and prevent atherosclerosis and its detrimental consequences like cardiovascular diseases and stroke. With and optimized reduction of elevated LDL levels with statins, the risk for cardiovascular diseases (CVD) can be reduced by 30%, indicating a residual remaining risk of 70% for the development and progression of CVD notifying still a high medical need for more effective antilipidemic drugs. Consequently, the search for novel lipid-modifying drugs is still one of the most active areas in research and development in the pharmaceutical industry. Major focus lies on approaches to LDL-lowering drugs superior to statins with regard to efficacy, safety, and patient compliance and on approaches modifying plasma levels and functionality of HDL particles based on the clinically validated inverse relationship between high-plasma HDL levels and the risk for CVD. The available drugs today for the treatment of dyslipidemia are small organic molecules or nonabsorbable polymers for binding of bile acids to be applied orally. Besides small molecules for novel targets, biological drugs such as monoclonal antibodies, antisense or gene-silencing oligonucleotides, peptidomimetics, reconstituted synthetic HDL particles and therapeutic proteins are novel approaches in clinical development are which have to be applied by injection or infusion. The promising clinical results of several novel drug candidates, particularly for LDL cholesterol lowering with monoclonal antibodies raised against PCSK9, may indicate more than a decade after the statins, the entrance of new breakthrough therapies to treat lipid disorders.

[An updated overview of the high intensity lipid lowering therapy in high cardiovascular risk patients]

Statins are highly effective drugs to decrease the plasma concentrations of atherogenic lipoproteins and prevent cardiovascular disease. The clinical practice guidelines recommend the use of high-intensity statins to lower LDL-cholesterol by at least 50% in patients with CVD and those at high cardiovascular risk. The recommendations for the treatment of hypercholesterolaemia by the ACC/AHA have led to a paradigm shift in cardiovascular prevention. These recommendations have abandoned the therapeutic goals of LDL-cholesterol, and recommend the treatment with statins of high or moderate intensity in four high cardiovascular risk groups. These recommendations are different from the European guidelines on cardiovascular disease prevention, in which their objectives are still towards LDL-cholesterol. This paper reviews this controversy from different angles and from the perspective of the Spanish Interdisciplinary Committee for Cardiovascular Disease Prevention. Intervention studies with high intensity statins in primary prevention, in patients with acute coronary syndrome, and with stable ischaemic heart disease are also described. Likewise, treatment with statins of high intensity is addressed in terms of their effectiveness in cardiovascular prevention and in terms of their safety, with particular attention to muscle effects, as well as taking into account the pharmacological characteristics of the different statins and the increased safety of those with less potential for interactions. Finally, new agents are described for the treatment of hypercholesterolaemia, with special emphasis on anti-PCSK9 monoclonal antibodies, a new therapeutic group for the treatment of hypercholesterolaemia that will offer a huge progress in the prevention of cardiovascular diseases.

Deferoxamine stimulates LDLR expression and LDL uptake in HepG2 cells

SCOPE

Iron overload contributes to the pathogenesis of atherosclerosis and iron chelators are beneficial through their antioxidant properties. Hepatic iron loading increases cholesterol synthesis. Whether iron depletion could affect hepatic cholesterol metabolism is unknown.

METHODS AND RESULTS

We examined the effect of the iron chelator deferoxamine (DFO) on mRNA expression of genes involved in cholesterol metabolism and/or cholesterol uptake. Our results revealed that DFO increases LDL receptor (LDLR) mRNA levels in human hepatocyte-derived cell lines HepG2 and Huh7 cells, and in K562 cells. In HepG2 cells, we observed that DFO increases (i) LDLR-mRNA levels in a time- and dose-dependent manner, (ii) LDLR-protein levels; (iii) cell surface LDLR; and (iv) LDL uptake. In contrast, the mRNA levels of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, sterol regulatory element-binding proteins, and the mRNA/protein levels of proprotein convertase subtilisin-kexin 9 were not modulated by DFO, suggesting that the LDLR regulation by DFO is not at the transcriptional or posttranslational levels. Since LDLR-mRNA was stabilized by DFO, a posttranscriptional mechanism is suggested for the DFO-mediated upregulation of LDLR.

CONCLUSION

DFO induced an increase in LDLR expression by a posttranscriptional mechanism resulting in an enhancement of LDL uptake in HepG2 cells, suggesting increased LDLR activity as one of the underlying causes of the hypocholesterolemic effect of iron reduction.