Updates in Small Interfering RNA for the Treatment of Dyslipidemias

PURPOSE OF REVIEW

Atherosclerotic cardiovascular disease (ASCVD) is still the leading cause of death worldwide. Despite excellent pharmacological approaches, clinical registries consistently show that many people with dyslipidemia do not achieve optimal management, and many of them are treated with low-intensity lipid-lowering therapies. Beyond the well-known association between low-density lipoprotein cholesterol (LDL-C) and cardiovascular prevention, the atherogenicity of lipoprotein(a) and the impact of triglyceride (TG)-rich lipoproteins cannot be overlooked. Within this landscape, the use of RNA-based therapies can help the treatment of difficult to target lipid disorders.

RECENT FINDINGS

The safety and efficacy of LDL-C lowering with the siRNA inclisiran has been documented in the open-label ORION-3 trial, with a follow-up of 4 years. While the outcome trial is pending, a pooled analysis of ORION-9, ORION-10, and ORION-11 has shown the potential of inclisiran to reduce composite major adverse cardiovascular events. Concerning lipoprotein(a), data of OCEAN(a)-DOSE trial with olpasiran show a dose-dependent drop in lipoprotein(a) levels with an optimal pharmacodynamic profile when administered every 12 weeks. Concerning TG lowering, although ARO-APOC3 and ARO-ANG3 are effective to lower apolipoprotein(apo)C-III and angiopoietin-like 3 (ANGPTL3) levels, these drugs are still in their infancy. In the era moving toward a personalized risk management, the use of siRNA represents a blossoming armamentarium to tackle dyslipidaemias for ASCVD risk reduction.

Pollution from fine particulate matter and atherosclerosis: A narrative review

According to the WHO, the entire global population is exposed to air pollution levels higher than recommended for health preservation. Air pollution is a complex mixture of nano- to micro-sized particles and gaseous components that poses a major global threat to public health. Among the most important air pollutants, causal associations have been established between particulate matter (PM), mainly < 2.5 μm, and cardiovascular diseases (CVD), i.e., hypertension, coronary artery disease, ischemic stroke, congestive heart failure, arrhythmias as well as total cardiovascular mortality. Aim of this narrative review is to describe and critically discuss the proatherogenic effects of PM_2.5 that have been attributed to many direct or indirect effects comprising endothelial dysfunction, a chronic low-grade inflammatory state, increased production of reactive oxygen species, mitochondrial dysfunction and activation of metalloproteases, all leading to unstable arterial plaques. Higher concentrations of air pollutants are associated with the presence of vulnerable plaques and plaque ruptures witnessing coronary artery instability. Air pollution is often disregarded as a CVD risk factor, in spite of the fact that it is one of the main modifiable factors relevant for prevention and management of CVD. Thus, not only structural actions should be taken in order to mitigate emissions, but health professionals should also take care to counsel patients on the risks of air pollution.

Nutraceutical approaches to non-alcoholic fatty liver disease (NAFLD): A position paper from the International Lipid Expert Panel (ILEP)

Non-Alcoholic Fatty Liver Disease (NAFLD) is a common condition affecting around 10-25% of the general adult population, 15% of children, and even > 50% of individuals who have type 2 diabetes mellitus. It is a major cause of liver-related morbidity, and cardiovascular (CV) mortality is a common cause of death. In addition to being the initial step of irreversible alterations of the liver parenchyma causing cirrhosis, about 1/6 of those who develop NASH are at risk also developing CV disease (CVD). More recently the acronym MAFLD (Metabolic Associated Fatty Liver Disease) has been preferred by many European and US specialists, providing a clearer message on the metabolic etiology of the disease. The suggestions for the management of NAFLD are like those recommended by guidelines for CVD prevention. In this context, the general approach is to prescribe physical activity and dietary changes the effect weight loss. Lifestyle change in the NAFLD patient has been supplemented in some by the use of nutraceuticals, but the evidence based for these remains uncertain. The aim of this Position Paper was to summarize the clinical evidence relating to the effect of nutraceuticals on NAFLD-related parameters. Our reading of the data is that whilst many nutraceuticals have been studied in relation to NAFLD, none have sufficient evidence to recommend their routine use; robust trials are required to appropriately address efficacy and safety.

Efficacy and safety of metabolic interventions for the treatment of severe COVID-19: in vitro, observational, and non-randomized open-label interventional study

Background

Viral infection is associated with a significant rewire of the host metabolic pathways, presenting attractive metabolic targets for intervention.

Methods

We chart the metabolic response of lung epithelial cells to SARS-CoV-2 infection in primary cultures and COVID-19 patient samples and perform in vitro metabolism-focused drug screen on primary lung epithelial cells infected with different strains of the virus. We perform observational analysis of Israeli patients hospitalized due to COVID-19 and comparative epidemiological analysis from cohorts in Italy and the Veteran's Health Administration in the United States. In addition, we perform a prospective non-randomized interventional open-label study in which 15 patients hospitalized with severe COVID-19 were given 145 mg/day of nanocrystallized fenofibrate added to the standard of care.

Results

SARS-CoV-2 infection produced transcriptional changes associated with increased glycolysis and lipid accumulation. Metabolism-focused drug screen showed that fenofibrate reversed lipid accumulation and blocked SARS-CoV-2 replication through a PPARα-dependent mechanism in both alpha and delta variants. Analysis of 3233 Israeli patients hospitalized due to COVID-19 supported in vitro findings. Patients taking fibrates showed significantly lower markers of immunoinflammation and faster recovery. Additional corroboration was received by comparative epidemiological analysis from cohorts in Europe and the United States. A subsequent prospective non-randomized interventional open-label study was carried out on 15 patients hospitalized with severe COVID-19. The patients were treated with 145 mg/day of nanocrystallized fenofibrate in addition to standard-of-care. Patients receiving fenofibrate demonstrated a rapid reduction in inflammation and a significantly faster recovery compared to patients admitted during the same period.

Conclusions

Taken together, our data suggest that pharmacological modulation of PPARα should be strongly considered as a potential therapeutic approach for SARS-CoV-2 infection and emphasizes the need to complete the study of fenofibrate in large randomized controlled clinical trials.

Funding

Funding was provided by European Research Council Consolidator Grants OCLD (project no. 681870) and generous gifts from the Nikoh Foundation and the Sam and Rina Frankel Foundation (YN). The interventional study was supported by Abbott (project FENOC0003).

Clinical trial number

NCT04661930.

Side effects of statins: from pathophysiology and epidemiology to diagnostic and therapeutic implications

Treatment with statins, inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, has proven beneficial preventive effects on cardiovascular events. However, discontinuation due to intolerance and non-adherence remain two of the major gaps in both primary and secondary prevention. This leads many patients with high-risk of atherosclerotic cardiovascular disease (ASCVD) to be inadequately treated or not to achieve target lipid level goals, and as consequence they undergo an increased risk of cardiovascular events. The aim of this review is thus to give an overview of the reasons for discontinuation and on the possible mechanisms behind them. Although statins, as a class, are generally safe, they are associated with an increased risk of diabetes mellitus and hepatic transaminase elevations. Incidence of cataracts or cognitive dysfunction and others presented in the literature (e.g. proteinuria and haematuria) have been never confirmed to have a causal link. Conversely, debated remains the effect on myalgia. Muscle side effects are the most commonly reported, although myalgia is still believed by some to be the result of a nocebo/drucebo effect. Concerning mechanisms behind muscular side effects, no clear conclusions have been reached. Thus, if on one side it is important to identify individuals either at higher risk to develop a side effect, or with confirmed risk factors and conditions of statin intolerance, on the other side alternative strategies should be identified to avoid an increased ASCVD risk.

PCSK9 Confers Inflammatory Properties to Extracellular Vesicles Released by Vascular Smooth Muscle Cells

Vascular smooth muscle cells (VSMCs) are key participants in both early- and late-stage atherosclerosis and influence neighbouring cells possibly by means of bioactive molecules, some of which are packed into extracellular vesicles (EVs). Proprotein convertase subtilisin/kexin type 9 (PCSK9) is expressed and secreted by VSMCs. This study aimed to unravel the role of PCSK9 on VSMCs-derived EVs in terms of content and functionality. EVs were isolated from human VSMCs overexpressing human PCSK9 (VSMCPCSK9-EVs) and tested on endothelial cells, monocytes, macrophages and in a model of zebrafish embryos. Compared to EVs released from wild-type VSMCs, VSMCPCSK9-EVs caused a rise in the expression of adhesion molecules in endothelial cells and of pro-inflammatory cytokines in monocytes. These acquired an increased migratory capacity, a reduced oxidative phosphorylation and secreted proteins involved in immune response and immune effector processes. Concerning macrophages, VSMCPCSK9-EVs enhanced inflammatory milieu and uptake of oxidized low-density lipoproteins, whereas the migratory capacity was reduced. When injected into zebrafish embryos, VSMCPCSK9-EVs favoured the recruitment of macrophages toward the site of injection. The results of the present study provide evidence that PCSK9 plays an inflammatory role by means of EVs, at least by those derived from smooth muscle cells of vascular origin.

Pharmacological rationale for the very early treatment of acute coronary syndrome with monoclonal antibodies anti-PCSK9

Immediate and aggressive lipid lowering therapies after acute coronary syndromes (ACS) and percutaneous coronary interventions (PCI) are supported by the ESC/EAS dyslipidemia guidelines, recommending the initiation of high-intensity statin therapy within the first 1-4 days of hospitalization. However, whether non statin lipid-lowering agents, added to statin treatment, could produce a further reduction in the risk of major adverse cardiovascular events (MACE) is still unknown. Thus, the efficacy of early treatment post-ACS with monoclonal antibodies (mAbs) anti PCSK9, evolocumab and alirocumab, is under investigation. The rationale to explore the rapid and aggressive pharmacological intervention with PCSK9 mAbs is supported by at least five confirmatory data in ACS: 1) circulating PCSK9 levels are raised during ACS 2) PCSK9 may stimulate platelet reactivity, this last being pivotal in the recurrence of ischemic events; 3) PCSK9 is associated with intraplaque inflammation, macrophage activation and endothelial dysfunction; 4) PCSK9 concentrations are associated with inflammation in the acute phase of ACS; and 5) statins raise PCSK9 levels promptly and, at times, dramatically. In this scenario, appropriate pharmacodynamic characteristics of anti PCSK9 therapies are a prerequisite for an effective response. Monoclonal antibodies act on circulating PCSK9 with a direct and rapid binding by blocking the interaction with the low-density lipoprotein receptor (LDLR). Evolocumab and alirocumab show a very rapid (within 4 h) and effective suppression of circulating unbound PCSK9 (- 95 % ÷ - 97 %). This inhibition results in a significant reduction of LDL-cholesterol (LDL-C) after 48 h (- 35 %) post injection with a full effect after 7-10 days (55-75 %). The complete and swift inhibitory action by evolocumab and alirocumab could have a potential clinical impact in ACS patients, also considering their potential inhibition of PCSK9 within the atherosclerotic plaque. Thus, administration of evolocumab or alirocumab is effective in lowering LDL-C levels in ACS, although the efficacy to prevent further cardiovascular (CV) events is still undetermined. The answer to this question will be provided by the ongoing clinical trials with evolocumab and alirocumab in ACS. In the present review we will discuss the pharmacological and biological rationale supporting the potential use of PCSK9 mAbs in ACS patients and the emerging evidence of evolocumab and alirocumab treatment in this clinical setting.

Bempedoic Acid: for Whom and When

PURPOSE OF REVIEW

The aim of creating an orally active non-statin cholesterol-lowering drug was achieved with bempedoic acid, a small linear molecule providing both a significant low-density lipoprotein cholesterol (LDL-C) reduction and an anti-inflammatory effect by decreasing high-sensitivity C-reactive protein. Bempedoic acid antagonizes ATP citrate-lyase, a cytosolic enzyme upstream of HMGCoA reductase which is the rate-limiting step of cholesterol biosynthesis. Bempedoic acid is a pro-drug converted to its active metabolite by very-long-chain acyl-CoA synthetase 1 which is present mostly in the liver and absent in skeletal muscles. This limits the risk of myalgia and myopathy. The remit of this review is to give clinical insights on the safety and efficacy of bempedoic acid and to understand for whom it should be prescribed.

RECENT FINDINGS

Bempedoic acid with a single daily dose (180 mg) reduces LDL-C by a mean 24.5% when given alone, by 18% when given on top of a major statin and by 38-40% when given in a fixed-dose combination with ezetimibe. Bempedoic acid does not lead to the risk of new-onset diabetes, and moderately improves the glycaemic profile. The extensive knowledge on bempedoic acid mechanism, metabolism and side effects has led to an improved understanding of the potential benefits of this agent and offers a possible alternative to cardiologists and clinical practitioners somewhat worn out today by the occurrence of the muscular side effects of statins.

Brain-Derived Neurotrophic Factor and Extracellular Vesicle-Derived miRNAs in an Italian Cohort of Individuals With Obesity: A Key to Explain the Link Between Depression and Atherothrombosis

Background

Obesity and depression are intertwined diseases often associated with an increased risk of cardiovascular (CV) complications. Brain-Derived Neurotrophic Factor (BDNF), altered in the brain both of subjects with depression and obesity, provides a potential link between depression and thrombosis. Since the relationship among peripheral BDNF, depression and obesity is not well-defined, the aim of the present report has been to address this issue taking advantage of the contribution played by extracellular vesicle (EV)-derived miRNAs.

Research Process

Associations among circulating BDNF, depression and EV-derived miRNAs related to atherothrombosis have been evaluated in a large Italian cohort of obese individuals (n = 743), characterized by the Beck Depression Inventory (BDI-II) score.

Results

BDI-II was negatively associated with BDNF levels without a significant impact of the rs6265 BDNF polymorphism; this association was modified by raised levels of IFN-γ. BDNF levels were linked to an increase of 80 EV-derived miRNAs and a decrease of 59 miRNAs related to atherosclerosis and thrombosis. Network analysis identified at least 18 genes targeted by these miRNAs, 7 of which involved in depression and CV risk. The observation of a possible link among BDNF, depression, and miRNAs related to atherothrombosis and depression in obesity is novel and may lead to a wider use of BDNF as a CV risk biomarker in this specific subject group.

Step-by-step diagnosis and management of the nocebo/drucebo effect in statin-associated muscle symptoms patients: a position paper from the International Lipid Expert Panel (ILEP)

Statin intolerance is a clinical syndrome whereby adverse effects (AEs) associated with statin therapy [most commonly statin-associated muscle symptoms (SAMS)] result in the discontinuation of therapy and consequently increase the risk of adverse cardiovascular outcomes. However, complete statin intolerance occurs in only a small minority of treated patients (estimated prevalence of only 3-5%). Many perceived AEs are misattributed (e.g. physical musculoskeletal injury and inflammatory myopathies), and subjective symptoms occur as a result of the fact that patients expect them to do so when taking medicines (the nocebo/drucebo effect)-what might be truth even for over 50% of all patients with muscle weakness/pain. Clear guidance is necessary to enable the optimal management of plasma in real-world clinical practice in patients who experience subjective AEs. In this Position Paper of the International Lipid Expert Panel (ILEP), we present a step-by-step patient-centred approach to the identification and management of SAMS with a particular focus on strategies to prevent and manage the nocebo/drucebo effect and to improve long-term compliance with lipid-lowering therapy.

Impact of Atorvastatin on Skeletal Muscle Mitochondrial Activity, Locomotion and Axonal Excitability-Evidence from ApoE-/- Mice

The cardiovascular benefit of statins is well established. However, only 20% of high-risk patients remain adequately adherent after 5 years of treatment. Among reasons for discontinuation, statin associated-muscle pain symptoms are the most prevalent. Aim of the present study was to evaluate the impact of high dose atorvastatin on skeletal muscle mitochondrial activity, aerobic and anaerobic exercise, and axonal excitability in a murine model of atherosclerosis. ApoE^-/- mice were fed 12 weeks a high-fat high-cholesterol diet alone or containing atorvastatin (40 mg/Kg/day). Outcomes were the evaluation of muscle mitochondrial functionality, locomotion, grip test, and axonal excitability (compound action potential recording analysis of Aα motor propioceptive, Aβ mechanoceptive and C nociceptive fibres). Atorvastatin led to a reduction in muscle mitochondrial biogenesis and mitochondrial ATP production. It did not affect muscular strength but led to a time-dependent motor impairment. Atorvastatin altered the responsiveness of mechanoceptive and nociceptive fibres, respectively, the Aβ and C fibres. These findings point out to a mild sensitization on mechanical, tactile and pain sensitivity. In conclusion, although the prevalence of muscular side effects from statins may be overestimated, understanding of the underlying mechanisms can help improve the therapeutic approach and reassure adherence in patients needing-to-be-treated.

The Role of High-Density Lipoprotein Cholesterol in 2022

PURPOSE OF THE REVIEW

High-density lipoproteins (HDL) are responsible for the transport in plasma of a large fraction of circulating lipids, in part from tissue mobilization. The evaluation of HDL-associated cholesterol (HDL-C) has provided a standard method for assessing cardiovascular (CV) risk, as supported by many contributions on the mechanism of this arterial benefit. The present review article will attempt to investigate novel findings on the role and mechanism of HDL in CV risk determination.

RECENT FINDINGS

The most recent research has been aimed to the understanding of how a raised functional capacity of HDL, rather than elevated levels per se, may be responsible for the postulated CV protection. Markedly elevated HDL-C levels appear instead to be associated to a raised coronary risk, indicative of a U-shaped relationship. While HDL-C reduction is definitely related to a raised CV risk, HDL-C elevations may be linked to non-vascular diseases, such as age-related macular disease. The description of anti-inflammatory, anti-oxidative and anti-infectious properties has indicated potential newer areas for diagnostic and therapeutic approaches. In the last two decades inconclusive data have arisen from clinical trials attempting to increase HDL-C pharmacologically or by way of recombinant protein infusions (most frequently with the mutant A-I _Milano); prevention of stent occlusion or heart failure treatment have shown instead significant promise. Targeted clinical studies are still ongoing.

Low Lipoprotein(a) Levels Predict Hepatic Fibrosis in Patients With Nonalcoholic Fatty Liver Disease

Dyslipidemia and cardiovascular complications are comorbidities of nonalcoholic fatty liver disease (NAFLD), which ranges from simple steatosis to nonalcoholic steatohepatitis, fibrosis, and cirrhosis up to hepatocellular carcinoma. Lipoprotein(a) (Lp(a)) has been associated with cardiovascular risk and metabolic abnormalities, but its impact on the severity of liver damage in patients with NAFLD remains to be clarified. Circulating Lp(a) levels were assessed in 600 patients with biopsy-proven NAFLD. The association of Lp(a) with liver damage was explored by categorizing serum Lp(a) into quartiles. The receiver operating characteristic curve was used to analyze the accuracy of serum Lp(a) in hepatic fibrosis prediction. Hepatic expression of lipoprotein A (LPA) and of genes involved in lipid metabolism and fibrogenic processes were evaluated by RNA sequencing in a subset of patients with NAFLD for whom Lp(a) dosage was available (n = 183). In patients with NAFLD, elevated Lp(a) levels were modestly associated with circulating lipids, carotid plaques, and hypertension (P < 0.05). Conversely, patients with low serum Lp(a) displayed insulin resistance (P < 0.05), transaminase elevation (P < 0.05), and increased risk of developing severe fibrosis (P = 0.007) and cirrhosis (P = 0.002). In addition, the diagnostic accuracy of Lp(a) in predicting fibrosis increased by combining it with transaminases (area under the curve fibrosis stage 4, 0.87; P < 0.0001). Hepatic LPA expression reflected serum Lp(a) levels (P = 0.018), and both were reduced with the progression of NAFLD (P < 0.05). Hepatic LPA messenger RNA levels correlated with those of genes involved in lipoprotein release, lipid synthesis, and fibrogenesis (P < 0.05). Finally, transmembrane 6 superfamily member 2 (TM6SF2) rs58542926, apolipoprotein E (ApoE) rs445925, and proprotein convertase subtilisin/kexin type 9 (PCSK9) rs7552841, known variants that modulate circulating lipids, may influence serum Lp(a) levels (P < 0.05). Conclusion: Circulating Lp(a) combined with transaminases may represent a novel noninvasive biomarker to predict advanced fibrosis in patients with NAFLD.

PCSK9 Inhibition and Risk of Diabetes: Should We Worry?

PURPOSE OF REVIEW

Since the clinical benefit of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors occurs in a setting of reducing low-density lipoprotein-cholesterol (LDL-C) to unprecedentedly low levels, it becomes of interest to investigate possible adverse effects pertaining to the risk of new-onset diabetes (NOD).

RECENT FINDINGS

While safety results reported in either meta-analyses or cardiovascular outcome trials FOURIER (with evolocumab) and ODYSSEY (with alirocumab) did not rise the incidence of NOD, Mendelian randomization analyses were almost concordant in showing an increased risk of NOD. This evidence was in line with post-marketing safety reports highlighting that evolocumab and alirocumab were primarily related to mild hyperglycaemia rather than diabetes, with most of the hyperglycaemic events occurring during the first 6 months of treatment. Considering the different nature of genetic studies and of randomized controlled trials, with careful monitoring of patients, particularly in the earlier phases of treatment, and the identification of those more susceptible to develop NOD, treatment with PCSK9 inhibitors should be of minimal concern.

Lipoprotein(a): Knowns, unknowns and uncertainties

Over the last 10 years, there have been advances on several aspects of lipoprotein(a) which are reviewed in the present article. Since the standard immunoassays for measuring lipoprotein(a) are not fully apo(a) isoform-insensitive, the application of an LC-MS/MS method for assaying molar concentrations of lipoprotein(a) has been advocated. Genome wide association, epidemiological, and clinical studies have established high lipoprotein(a) as a causal risk factor for atherosclerotic cardiovascular diseases (ASCVD). However, the relative importance of molar concentration, apo(a) isoform size or variants within the LPA gene is still controversial. Lipoprotein(a)-raising single nucleotide polymorphisms has not been shown to add on value in predicting ASCVD beyond lipoprotein(a) concentrations. Although hyperlipoproteinemia(a) represents an important confounder in the diagnosis of familial hypercholesterolemia (FH), it enhances the risk of ASCVD in these patients. Thus, identification of new cases of hyperlipoproteinemia(a) during cascade testing can increase the identification of high-risk individuals. However, it remains unclear whether FH itself increases lipoprotein(a). The ASCVD risk associated with lipoprotein(a) seems to follow a linear gradient across the distribution, regardless of racial subgroups and other risk factors. The inverse association with the risk of developing type 2 diabetes needs consideration as effective lipoprotein(a) lowering therapies are progressing towards the market. Considering that Mendelian randomization analyses have identified the degree of lipoprotein(a)-lowering that is required to achieve ASCVD benefit, the findings of the ongoing outcome trial with pelacarsen will clarify whether dramatically lowering lipoprotein(a) levels can reduce the risk of ASCVD.

Impact of nutraceuticals on markers of systemic inflammation: Potential relevance to cardiovascular diseases - A position paper from the International Lipid Expert Panel (ILEP)

Inflammation is a marker of arterial disease stemming from cholesterol-dependent to -independent molecular mechanisms. In recent years, the role of inflammation in atherogenesis has been underpinned by pharmacological approaches targeting systemic inflammation that have led to a significant reduction in cardiovascular disease (CVD) risk. Although the use of nutraceuticals to prevent CVD has largely focused on lipid-lowering (e.g, red-yeast rice and omega-3 fatty acids), there is growing interest and need, especially now in the time of coronavirus pandemic, in the use of nutraceuticals to reduce inflammatory markers, and potentially the inflammatory CVD burden, however, there is still not enough evidence to confirm this. Indeed, diet is an important lifestyle determinant of health and can influence both systemic and vascular inflammation, to varying extents, according to the individual nutraceutical constituents. Thus, the aim of this Position Paper is to provide the first attempt at recommendations on the use of nutraceuticals with effective anti-inflammatory properties.

Nonalcoholic fatty liver disease or metabolic dysfunction-associated fatty liver disease diagnoses and cardiovascular diseases: From epidemiology to drug approaches

BACKGROUND

A consensus of experts has proposed to replace the term nonalcoholic fatty liver disease (NAFLD), whose global prevalence is 25%, with metabolic dysfunction-associated fatty liver disease (MAFLD), to describe more appropriately the liver disease related to metabolic derangements. MAFLD is closely intertwined with type 2 diabetes, obesity, dyslipidaemia, all linked to a rise in the risk of cardiovascular disease (CVDs). Since controversy still stands on whether or not NAFLD/MAFLD raises the odds of CVD, the present review aims to evaluate the impact of NAFLD/MAFLD aetiologies on CV health and the potential correction by dietary and drug approaches.

RESULTS

Epidemiological studies indicate that NAFLD raises risk of fatal or non-fatal CVD events. NAFLD patients have a higher prevalence of arterial plaques and stiffness, coronary calcification, and endothelial dysfunction. Although genetic and environmental factors strongly contribute to NAFLD pathogenesis, a Mendelian randomization analysis indicated that the PNPLA3 genetic variant leading to NAFLD may not be causally associated with CVD risk. Among other genetic variants related to NAFLD, TM6SF2 appears to be protective, whereas MBOAT7 may favour venous thromboembolism.

CONCLUSIONS

NAFLD is correlated to a higher CVD risk which may be ameliorated by dietary interventions. This is not surprising, since new criteria defining MAFLD include other metabolic risk abnormalities fuelling development of serious adverse extrahepatic outcomes, for example CVD. The present lack of a targeted pharmacological approach makes the identification of patients with liver disease at higher CVD risk (eg diabetes, hypertension, obesity or high levels of C-reactive protein) of major clinical interest.

Cardiovascular risk and testosterone - from subclinical atherosclerosis to lipoprotein function to heart failure

The cardiovascular (CV) benefit and safety of treating low testosterone conditions is a matter of debate. Although testosterone deficiency has been linked to a rise in major adverse CV events, most of the studies on testosterone replacement therapy were not designed to assess CV risk and thus excluded men with advanced heart failure or recent history of myocardial infarction or stroke. Besides considering observational, interventional and prospective studies, this review article evaluates the impact of testosterone on atherosclerosis process, including lipoprotein functionality, progression of carotid intima media thickness, inflammation, coagulation and thromboembolism, quantification of plaque volume and vascular calcification. Until adequately powered studies evaluating testosterone effects in hypogonadal men at increased CV risk are available (TRAVERSE trial), clinicians should ponder the use of testosterone in men with atherosclerotic cardiovascular disease and discuss benefit and harms with the patients.

Proprotein Convertase Subtilisin/Kexin Type 9: A View beyond the Canonical Cholesterol-Lowering Impact

Proprotein convertase subtilisin/kexin type 9 (PCSK9), mainly synthetized and released by the liver, represents one of the key regulators of low-density lipoprotein cholesterol. Although genetic and interventional studies have demonstrated that lowering PCSK9 levels corresponds to a cardiovascular benefit, identification of non-cholesterol-related processes has emerged since its discovery. Besides liver, PCSK9 is also expressed in many tissues (eg, intestine, endocrine pancreas, and brain). The aim of the present review is to describe and discuss PCSK9 pathophysiology and possible non-lipid-lowering effects whether already extensively characterized (eg, inflammatory burden of atherosclerosis, triglyceride-rich lipoprotein metabolism, and platelet activation), or to be unraveled (eg, in adipose tissue). The identification of novel transcriptional factors in the promoter region of human PCSK9 (eg, ChREBP) characterizes new mechanisms explaining how controlling intrahepatic glucose may be a therapeutic strategy to reduce cardiovascular risk in type 2 diabetes. Finally, the evidence describing PCSK9 as involved in cell proliferation and apoptosis raises the possibility of this protein being involved in cancer risk.

Maternal exposure to air pollutants, PCSK9 levels, fetal growth and gestational age - An Italian cohort

OBJECTIVE

Exposure to airborne pollutants during pregnancy appears to be associated with uterine growth restriction and adverse neonatal outcome. Proprotein convertase subtilisin/kexin type (PCSK9), the key modulator of low-density lipoprotein (LDL) metabolism, increases following particulate matter (PM₁₀) exposure. Because maternal cholesterol is required for fetal growth, PCSK9 levels could be used to evaluate the potential impact of airborne pollutants on fetal growth.

DESIGN

A cohort of 134 healthy women during early pregnancy (11-12 weeks of gestational age) was studied.

RESULTS

A significant association between circulating PCSK9 levels and three tested air pollutants (PM₁₀, PM_2.5, nitric oxide (NO₂)) was found. Of importance, gestational age at birth was reduced by approximately 1 week for each 100 ng/mL rise in circulating PCSK9 levels, an effect that became more significant at the highest quartile of PM_2.5 (with a 1.8 week advance in delivery date for every 100 ng/mL rise in circulating PCSK9; p for interaction = 0.026). This finding was supported by an elevation of the odds ratio for urgent cesarean delivery for each 100 ng/mL rise in PCSK9 (2.99, 95% CI, 1.22-6.57), similar trends being obtained for PM₁₀ and NO₂.

CONCLUSIONS

The association between exposure to air pollutants during pregnancy and elevation in PCSK9 advances our understanding of the unforeseen influences of environmental exposure in terms of pregnancy associated disorders.

The effect of transgender hormonal treatment on high density lipoprotein cholesterol efflux capacity

BACKGROUND AND AIMS

A decrease in high-density lipoprotein (HDL)-cholesterol concentrations during transgender hormone therapy has been shown. However, the ability of HDL to remove cholesterol from arterial wall macrophages, termed cholesterol efflux capacity (CEC), has proven to be a better predictor of cardiovascular disease (CVD) largely independently of HDL-concentrations. In addition, the serum capacity to load macrophages with cholesterol (cholesterol loading capacity, CLC) represents an index of pro-atherogenic potential. As transgender individuals are exposed to lifelong exogenous hormone therapy (HT), it becomes of interest to study whether HDL-CEC and serum CLC are affected by HT. HDL-CEC and serum CLC have been evaluated in 15 trans men treated with testosterone and in 15 trans women treated with estradiol and cyproterone acetate at baseline and after 12 months of HT.

METHODS

Total HDL-CEC from macrophages and its major contributors, the ATP-binding cassette transporters (ABC) A1 and ABCG1 HDL-CEC and HDL-CEC by aqueous diffusion were determined by a radioisotopic assay. CLC was evaluated in human THP-1 macrophages.

RESULTS

In trans women, total HDL-CEC decreased by 10.8% (95%CI: -14.3;-7.3; p < 0.001), ABCA1 HDL-CEC by 23.8% (-34.7; -12.9; p < 0.001) and aqueous diffusion HDL-CEC by 4.8% (-8.4;-1.1; p < 0.01). In trans men, only aqueous diffusion HDL-CEC decreased significantly, -9.8% (-15.7;-3.9; p < 0.01). ABCG1 HDL-CEC did not change in either group. Serum CLC and HDL subclass distribution were not modified by HT in both groups.

CONCLUSIONS

Total HDL-CEC decreased during HT in trans women, with a specific reduction in ABCA1 CEC. This finding might contribute to a higher CVD risk.

Gender difference in lipoprotein(a) concentration as a predictor of coronary revascularization in patients with known coronary artery disease

BACKGROUND AND AIMS

Whether there is a gender difference in the impact of elevated plasma Lp(a) levels on recurrent coronary events remains unclear. We, therefore, evaluated the association between Lp(a) levels and the occurrence of major adverse coronary events in a large series of coronary patients (32% women).

METHODS

This single-center prospective cohort study investigated 3034 consecutive patients admitted to the Coronary Care Unit with a diagnosis of coronary ischemia. According to the inclusion criteria, 2374 patients completed the follow-up (mean of 2 years). The end-points were non-fatal myocardial infarction (MI), revascularization and coronary deaths.

RESULTS

Elevated Lp(a) levels were significantly associated with rate of revascularization, but not with non-fatal MI and cardiac death. According to Lp(a) stratification (≤30 mg/dl, >30-50 mg/dl and ≥50 mg/dl), there was a significant rise of revascularization events in the whole sample of participants, with a trend in hazard ratio (HR) of 1.23 (95% CI 1.04-1.46) and a 6% rise for every 10 mg/dl increment in Lp(a) levels. This effect was mainly driven by women (HR 2.04, 95%CI 1.33-3.12) who showed a 14% incremental risk for every 10 mg/dl rise in Lp(a) levels.

CONCLUSIONS

In patients with coronary artery disease, elevated plasma Lp(a) levels were found to be a potentially useful predictor of the need for coronary revascularizations, especially in women.

Depression and cardiovascular risk-association among Beck Depression Inventory, PCSK9 levels and insulin resistance

BACKGROUND

Depression and cardiovascular disease (CVD) are among the most common causes of disability in high-income countries, depression being associated with a 30% increased risk of future CV events. Depression is twice as common in people with diabetes and is associated with a 60% rise in the incidence of type 2 diabetes, an independent CVD risk factor. Proprotein convertase subtilisin/kexin type 9 (PCSK9), a key regulator of low-density lipoprotein cholesterol, has been related to a large number of CV risk factors, including insulin resistance. Aim of this study was to investigate whether the presence of depression could affect PCSK9 levels in a population of obese subjects susceptible to depressive symptoms and how these changes may mediate a pre-diabetic risk.

RESULTS

In 389 obese individuals, the Beck Depression Inventory (BDI-II) was significantly associated with PCSK9 levels. For every one-unit increment in BDI-II score, PCSK9 rose by 1.85 ng/mL. Depression was associated also with the HOMA-IR (homeostatic model assessment index of insulin resistance), 11% of this effect operating indirectly via PCSK9.

CONCLUSIONS

This study indicates a possible mechanism linking depression and insulin resistance, a well-known CV risk factor, providing evidence for a significant role of PCSK9.

Unravelling the health effects of fasting: a long road from obesity treatment to healthy life span increase and improved cognition

In recent years a revival of interest has emerged in the health benefits of intermittent fasting and long-term fasting, as well as of other related nutritional strategies. In addition to meal size and composition a new focus on time and frequency of meals has gained attention. The present review will investigate the effects of the main forms of fasting, activating the metabolic switch from glucose to fat and ketones (G-to-K), starting 12-16 h after cessation or strong reduction of food intake. During fasting the deactivation of mTOR regulated nutrient signalling pathways and activation of the AMP protein kinase trigger cell repair and inhibit anabolic processes. Clinical and animal studies have clearly indicated that modulating diet and meal frequency, as well as application of fasting patterns, e.g. intermittent fasting, periodic fasting, or long-term fasting are part of a new lifestyle approach leading to increased life and health span, enhanced intrinsic defences against oxidative and metabolic stresses, improved cognition, as well as a decrease in cardiovascular risk in both obese and non-obese subjects. Finally, in order to better understand the mechanisms beyond fasting-related changes, human studies as well as non-human models closer to human physiology may offer useful clues.KEY-MESSAGESBiochemical changes during fasting are characterised by a glucose to ketone switch, leading to a rise of ketones, advantageously used for brain energy, with consequent improved cognition.Ketones reduce appetite and help maintain effective fasting.Application of fasting patterns increases healthy life span and defences against oxidative and metabolic stresses.Today's strategies for the use of therapeutic fasting are based on different protocols, generally relying on intermittent fasting, of different duration and calorie intake.Long-term fasting, with durations between 5 and 21 days can be successfully repeated in the course of a year.

Lipoprotein(a) Lowering-From Lipoprotein Apheresis to Antisense Oligonucleotide Approach

It is well-known that elevated lipoprotein(a)—Lp(a)—levels are associated with a higher risk of cardiovascular (CV) mortality and all-cause mortality, although a standard pharmacotherapeutic approach is still undefined for patients with high CV risk dependent on hyperlipoproteinemia(a). Combined with high Lp(a) levels, familial hypercholesterolemia (FH) leads to a greater CVD risk. In suspected FH patients, the proportion of cases explained by a rise of Lp(a) levels ranges between 5% and 20%. In the absence of a specific pharmacological approach able to lower Lp(a) to the extent required to achieve CV benefits, the most effective strategy today is lipoprotein apheresis (LA). Although limited, a clear effect on Lp(a) is exerted by PCSK9 antagonists, with apparently different mechanisms when given with statins (raised catabolism) or as monotherapy (reduced production). In the era of RNA-based therapies, a new dawn is represented by the use of antisense oligonucleotides APO(a)L_rx, able to reduce Lp(a) from 35% to over 80%, with generally modest injection site reactions. The improved knowledge of Lp(a) atherogenicity and possible prevention will be of benefit for patients with residual CV risk remaining after the most effective available lipid-lowering agents.

Clinical approach to the inflammatory etiology of cardiovascular diseases

Inflammation is an obligatory marker of arterial disease, both stemming from the inflammatory activity of cholesterol itself and from well-established molecular mechanisms. Raised progenitor cell recruitment after major events and clonal hematopoiesis related mechanisms have provided an improved understanding of factors regulating inflammatory phenomena. Trials with inflammation antagonists have led to an extensive evaluation of biomarkers such as the high sensitivity C reactive protein (hsCRP), not exerting a causative role, but frequently indicative of the individual cardiovascular (CV) risk. Aim of this review is to provide indication on the anti-inflammatory profile of agents of general use in CV prevention, i.e. affecting lipids, blood pressure, diabetes as well nutraceuticals such as n-3 fatty acids. A crucial issue in the evaluation of the benefit of the anti-inflammatory activity is the frequent discordance between a beneficial activity on a major risk factor and associated changes of hsCRP, as in the case of statins vs PCSK9 antagonists. In hypertension, angiotensin converting enzyme inhibitors exert an optimal anti-inflammatory activity, vs the case of sartans. The remarkable preventive activity of SLGT-2 inhibitors in heart failure is not associated with a clear anti-inflammatory mechanism. Finally, icosapent ethyl has been shown to reduce the CV risk in hypertriglyceridemia, with a 27 % reduction of hsCRP. The inflammation-based approach to arterial disease has considerably gained from an improved understanding of the clinical diagnostic strategy and from a better knowledge on the mode of action of numerous agents, including nutraceuticals.

Pharmacological aspects of ANGPTL3 and ANGPTL4 inhibitors: New therapeutic approaches for the treatment of atherogenic dyslipidemia

Among the determinants of atherosclerotic cardiovascular disease (ASCVD), genetic and experimental evidence has provided data on a major role of angiopoietin-like proteins 3 and 4 (ANGPTL3 and ANGPTL4) in regulating the activity of lipoprotein lipase (LPL), antagonizing the hydrolysis of triglycerides (TG). Indeed, beyond low-density lipoprotein cholesterol (LDL-C), ASCVD risk is also dependent on a cluster of metabolic abnormalities characterized by elevated fasting and post-prandial levels of TG-rich lipoproteins and their remnants. In a head-to-head comparison between murine models for ANGPTL3 and ANGPTL4, the former was found to be a better pharmacological target for the treatment of hypertriglyceridemia. In humans, loss-of-function mutations of ANGPTL3 are associated with a marked reduction of plasma levels of VLDL, low-density lipoprotein (LDL) and high-density lipoprotein (HDL). Carriers of loss-of-function mutations of ANGPTL4 show instead lower TG-rich lipoproteins and a modest but significant increase of HDL. The relevance of ANGPTL3 and ANGPTL4 as new therapeutic targets is proven by the development of monoclonal antibodies or antisense oligonucleotides. Studies in animal models, including non-human primates, have demonstrated that short-term treatment with monoclonal antibodies against ANGPTL3 and ANGPTL4 induces activation of LPL and a marked reduction of plasma TG-rich-lipoproteins, apparently without any major side effects. Inhibition of both targets also partially reduces LDL-C, independent of the LDL receptor. Similar evidence has been observed with the antisense oligonucleotide ANGPTL3-L_RX. The genetic studies have paved the way for the development of new ANGPTL3 and 4 antagonists for the treatment of atherogenic dyslipidemias. Conclusive data of phase 2 and 3 clinical trials are still needed in order to define their safety and efficacy profile.

Differential effects of red yeast rice, Berberis aristata and Morus alba extracts on PCSK9 and LDL uptake

BACKGROUND AND AIMS

The novel nutraceutical combination containing red yeast rice (monacolin K 3.3 mg), Berberis aristata cortex extract (Berberine 531.25 mg) and Morus alba leaves extract (1-deoxynojirimycin 4 mg) is effective in the management of elevated plasma low-density lipoprotein cholesterol (LDL-C) levels. The aim of the present study was to investigate the effects of the three components on proprotein convertase subtilisin/kexin type 9 (PCSK9), a key regulator of LDL receptor (LDLR) expression, in hepatocyte cell lines and to compare their effects on LDL cellular uptake.

METHODS AND RESULTS

HepG2 and Huh7 cells were incubated with B. aristata cortex extract (BCE), red yeast rice (RYR) and M. alba leaves extract (MLE) alone or in combination for 24 h. RYR (50 μg/mL) increased PCSK9 protein expression (Western blot analysis and ELISA), PCSK9 mRNA (qPCR) and its promoter activity (luciferase reporter assay). BCE (40 μg/mL) reduced instead PCSK9 expression, mRNA levels and promoter activity. MLE determined a concentration-dependent reduction of PCSK9 at the mRNA and protein levels, with a maximal reduction at 1 mg/mL, without significant changes of PCSK9 promoter activity. MLE also downregulated the expression of 3-hydroxy-3-methyl-3-glutaryl coenzyme A reductase and fatty acid synthase mRNA levels. The combination of RYR, BCE and MLE reduced the PCSK9 mRNA and protein levels, as well as the promoter activity. Finally, the single components and their combination induced LDL receptor and LDL uptake by the hepatocytes.

CONCLUSION

The positive effect of MLE on PCSK9 supports the rationale of using the nutraceutical combination of RYR, BCE and MLE to control hyperlipidemic conditions.

HDL therapy today: from atherosclerosis, to stent compatibility to heart failure

Epidemiologically, high-density lipoprotein (HDL) cholesterol levels have been inversely associated to cardiovascular (CV) events, although a Mendelian Randomisation Study had failed to establish a clear causal role. Numerous atheroprotective mechanisms have been attributed to HDL, the main being the ability to promote cholesterol efflux from arterial walls; anti-inflammatory effects related to HDL ligands such as S1P (sphingosine-1-phosphate), resolvins and others have been recently identified. Experimental studies and early clinical investigations have indicated the potential of HDL to slow progression or induce regression of atherosclerosis. More recently, the availability of different HDL formulations, with different phospholipid moieties, has allowed to test other indications for HDL therapy. Positive reports have come from studies on coronary stent biocompatibility, where the use of HDL from different sources reduced arterial cell proliferation and thrombogenicity. The observation that low HDL-C levels may be associated with an enhanced risk of heart failure (HF) has also suggested that HDL therapy may be applied to this condition. HDL infusions or apoA-I gene transfer were able to reverse heart abnormalities, reduce diastolic resistance and improve cardiac metabolism. HDL therapy may be effective not only in atherosclerosis, but also in other conditions, of relevant impact on human health.Key messagesHigh-density lipoproteins have as a major activity that of removing excess cholesterol from tissues (particularly arteries).Knowledge on the activity of high-density lipoproteins on health have however significantly widened.HDL-therapy may help to improve stent biocompatibility and to reduce peripheral arterial resistance in heart failure.

A new dawn for managing dyslipidemias: The era of rna-based therapies

The high occurrence of atherosclerotic cardiovascular disease (ASCVD) events is still a major public health issue. Although a major determinant of ASCVD event reduction is the absolute change of low-density lipoprotein-cholesterol (LDL-C), considerable residual risk remains and new therapeutic options are required, in particular, to address triglyceride-rich lipoproteins and lipoprotein(a) [Lp(a)]. In the era of Genome Wide Association Studies and Mendelian Randomization analyses aimed at increasing the understanding of the pathophysiology of ASCVD, RNA-based therapies may offer more effective treatment options. The advantage of oligonucleotide-based treatments is that drug candidates are targeted at highly specific regions of RNA that code for proteins that in turn regulate lipid and lipoprotein metabolism. For LDL-C lowering, the use of inclisiran - a silencing RNA that inhibits proprotein convertase subtilisin/kexin type 9 (PCSK9) synthesis - has the advantage that a single s.c. injection lowers LDL-C for up to 6 months. In familial hypercholesterolemia, the use of the antisense oligonucleotide (ASO) mipomersen, targeting apolipoprotein (apoB) to reduce LDL-C, has been a valuable therapeutic approach, despite unquestionable safety concerns. The availability of specific ASOs lowering Lp(a) levels will allow rigorous testing of the Lp(a) hypothesis; by dramatically reducing plasma triglyceride levels, Volanesorsen (APOC3) and angiopoietin-like 3 (ANGPTL3)-LRx will further clarify the causality of triglyceride-rich lipoproteins in ASCVD. The rapid progress to date heralds a new dawn in therapeutic lipidology, but outcome, safety and cost-effectiveness studies are required to establish the role of these new agents in clinical practice.

High-Density Lipoprotein Function Is Reduced in Patients Affected by Genetic or Idiopathic Hypogonadism

CONTEXT

Low testosterone levels are associated with an increased incidence of cardiovascular (CV) events, but the underlying biochemical mechanisms are not fully understood. The clinical condition of hypogonadism offers a unique model to unravel the possible role of lipoprotein-associated abnormalities in CV risk. In particular, the assessment of the functional capacities of high-density lipoproteins (HDLs) may provide insights besides traditional risk factors.

DESIGN

To determine whether reduced testosterone levels correlate with lipoprotein function, HDL cholesterol (HDL-C) efflux capacity (CEC) and serum cholesterol loading capacity (CLC).

PARTICIPANTS

Genetic and idiopathic hypogonadal patients (n = 20) and control subjects (n = 17).

RESULTS

Primary and secondary hypogonadal patients presented with lower HDL ATP-binding cassette transporter A1 (ABCA1)-, ATP-binding cassette transporter G1 (ABCG1)-, and aqueous diffusion-mediated CEC (-19.6%, -40.9%, and -12.9%, respectively), with a 16.2% decrement of total CEC. In the whole series, positive correlations between testosterone levels and both total HDL CEC (r2 = 0.359, P = 0.0001) and ABCG1 HDL CEC (r2 = 0.367, P = 0.0001) were observed. Conversely, serum CLC was markedly raised (+43%) in hypogonadals, increased, to a higher extent, in primary vs secondary hypogonadism (18.45 ± 2.78 vs 15.15 ± 2.10 µg cholesterol/mg protein) and inversely correlated with testosterone levels (r2 = 0.270, P = 0.001). HDL-C concentrations did not correlate with either testosterone levels, HDL CEC (total, ABCG1, and ABCA1) or serum CLC.

CONCLUSIONS

In hypogonadal patients, proatherogenic lipoprotein-associated changes are associated with lower cholesterol efflux and increased influx, thus offering an explanation for a potentially increased CV risk.

PCSK9 inhibition and inflammation: A narrative review

Atherosclerotic cardiovascular disease (ASCVD) remains a leading cause of morbidity and mortality despite excellent pharmacological and revascularization approaches. Low-density lipoproteins (LDL) are undoubtedly the most significant biochemical variables associated with atheroma, however, compelling data identify inflammation as critical for the maintenance of the atherosclerotic process, underlying some of the most feared vascular complications. Although its causal role is questionable, high-sensitivity C-reactive protein (hs-CRP) represents a major biomarker of inflammation and associated risk in CVD. While statin-associated reduced risk may be related to the lowering of both LDL-C and hs-CRP, PCSK9 inhibitors leading to dramatic LDL-C reductions do no alter hs-CRP levels. On the other hand, hs-CRP levels identify groups of patients with a high risk of CV disease achieving better ASCVD prevention in response to PCSK9 inhibition. In the FOURIER study, even in patients with extremely low levels of LDL-C, there was a stepwise risk increment according to the values of hs-CRP: +9% (<1 mg/L), +10.8% (1-3 mg/L) and +13.1% (>3 mg/L). Likewise, in the SPIRE-1 and -2 studies, bococizumab patients with hs-CRP> 3 mg/L had a 60% greater risk of future CV events. Most of the patients enrolled in the PCSK9 trials were on maximally tolerated statin therapy at baseline, and an elevated hs-CRP may reflect residual inflammatory risk after standard LDL-C lowering therapy. Moreover, data on changes in inflammation markers in carriers of PCSK9 loss-of-function mutations are scanty and not conclusive, thus, evidence from the effects of anti-inflammatory molecules on PCSK9 levels might help unravel this hitherto complex tangle.

Recent advances in synthetic pharmacotherapies for dyslipidaemias

Despite the demonstrated benefits of statins and injectable biologics, there is a need for new and safe oral agents for addressing classical lipid targets, low-density lipoprotein cholesterol (LDL-C), triglycerides and high-density lipoprotein cholesterol (HDL-C). LDL-C is unquestionably causal in the development of atherogenesis and atherosclerotic cardiovascular disease, but new options are required to address triglyceride-rich lipoproteins and lipoprotein(a). For hypercholesterolaemia, pitavastatin provides a very low dose and potent statin that does not adversely affect glucose metabolism; bempedoic acid acts at a biochemical step preceding hydroxymethylglutaryl-CoA reductase and is not associated with muscular side effects. For hypertriglyceridaemia, pemafibrate displays a unique and selective agonist activity on peroxisomal proliferator activated receptor-α that does not elevate homocysteine or creatinine. Although omega-3 fatty acids supplementation is not effective in secondary prevention, high dose eicosapentaenoic ethyl ester can lead to a remarkable fall in first and recurrent events in high risk patients with hypertriglyceridaemia/low HDL-C. Gemcabene, a dicarboxylic acid regulating apolipoprotein B-100, is effective in reducing both cholesterol and triglycerides. Among cholesteryl ester transfer protein antagonists that elevate HDL-C, only anacetrapib reduces cardiovascular events. Probucol stimulates reverse cholesteryl ester transport, lowers LDL-C stabilizing plaques and may lower incidence of cardiovascular events. These agents, which act through novel mechanisms, afford good and potentially safe treatment choices that may increase adherence and the attainment of therapeutic targets.

ETC-1002 (Bempedoic acid) for the management of hyperlipidemia: from preclinical studies to phase 3 trials

INTRODUCTION

Tolerability problems in treating hypercholesterolemic patients undergoing statin treatment are of growing concern to physicians and patients, thus underlining the need for an agent with a similar mechanism but minimal side effects. A drug with a somewhat similar mechanism to statins but free of muscular side effects is ETC-1002 (bempedoic acid). It inhibits cholesterol biosynthesis at a step preceding HMG-CoA reductase, i.e. ATP citrate lyase (ACLY). A prodrug, ETC-1002 is converted to the active agent only in liver, not in skeletal muscle, and this may prevent any myotoxic activity. Area covered: The mechanism of ETC-1002 activity is described in detail, considering that ACLY inhibition markedly attenuated atherosclerosis in animal models. Clinical studies are also reported. Expert opinion: Present day LDL-C lowering treatments lead to significant reductions of cardiovascular (CV) events but, at times, the need to interrupt statin treatment appears to be dangerous due to a rapid rise in CV risk. The excellent tolerability of ETC-1002 makes it a useful alternative, either alone or as an adjunct to ezetimibe, for patients with statin intolerance needing to achieve significant CV risk reduction. ETC-1002 is also associated with a marked fall in high-sensitivity C-reactive protein.

Nutraceutical approach for the management of cardiovascular risk - a combination containing the probiotic Bifidobacterium longum BB536 and red yeast rice extract: results from a randomized, double-blind, placebo-controlled study

BACKGROUND

Probiotics incorporated into dairy products have been shown to reduce total (TC) and LDL cholesterolemia (LDL-C) in subjects with moderate hypercholesterolemia. More specifically, probiotics with high biliary salt hydrolase activity, e.g. Bifidobacterium longum BB536, may decrease TC and LDL-C by lowering intestinal cholesterol reabsorption and, combined with other nutraceuticals, may be useful to manage hypercholesterolemia in subjects with low cardiovascular (CV) risk. This study was conducted to evaluate the efficacy and safety of a nutraceutical combination containing Bifidobacterium longum BB536, red yeast rice (RYR) extract (10 mg/day monacolin K), niacin, coenzyme Q10 (Lactoflorene Colesterolo®). The end-points were changes of lipid CV risk markers (LDL-C, TC, non-HDL-cholesterol (HDL-C), triglycerides (TG), apolipoprotein B (ApoB), HDL-C, apolipoprotein AI (ApoAI), lipoprotein(a) (Lp(a), proprotein convertase subtilisin/kexin type 9 (PCSK9)), and of markers of cholesterol synthesis/absorption.

METHODS

A 12-week randomized, parallel, double-blind, placebo-controlled study. Thirty-three subjects (18-70 years) in primary CV prevention and low CV risk (SCORE: 0-1% in 24 and 2-4% in 9 subjects; LDL-C: 130-200 mg/dL) were randomly allocated to either nutraceutical (N = 16) or placebo (N = 17).

RESULTS

Twelve-week treatment with the nutraceutical combination, compared to placebo, significantly reduced TC (- 16.7%), LDL-C (- 25.7%), non-HDL-C (- 24%) (all p < 0.0001), apoB (- 17%, p = 0.003). TG, HDL-C, apoAI, Lp(a), PCSK9 were unchanged. Lathosterol:TC ratio was significantly reduced by the nutraceutical combination, while campesterol:TC ratio and sitosterol:TC ratio did not change, suggesting reduction of synthesis without increased absorption of cholesterol. No adverse effects and a 97% compliance were observed.

CONCLUSIONS

A 12-week treatment with a nutraceutical combination containing the probiotic Bifidobacterium longum BB536 and RYR extract significantly improved the atherogenic lipid profile and was well tolerated by low CV risk subjects.

TRIAL REGISTRATION

NCT02689934 .

Changes in circulating pro-protein convertase subtilisin/kexin type 9 levels - experimental and clinical approaches with lipid-lowering agents

Regulation of pro-protein convertase subtilisin/kexin type 9 (PCSK9) by drugs has led to the development of a still small number of agents with powerful activity on low-density lipoprotein cholesterol levels, associated with a significant reduction of cardiovascular events in patients in secondary prevention. The Further Cardiovascular Outcomes Research with PCSK9 Inhibition in Subjects with Elevated Risk (FOURIER) and Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab (ODYSSEY OUTCOMES) studies, with the two available PCSK9 antagonists, i.e. evolocumab and alirocumab, both reported a 15% reduction in major adverse cardiovascular events. Regulation of PCSK9 expression is dependent upon a number of factors, partly genetic and partly associated to a complex transcriptional system, mainly controlled by sterol regulatory element binding proteins. PCSK9 is further regulated by concomitant drug treatments, particularly by statins, enhancing PCSK9 secretion but decreasing its stimulatory phosphorylated form (S688). These complex transcriptional mechanisms lead to variable circulating levels making clinical measurements of plasma PCSK9 for cardiovascular risk assessment a debated matter. Determination of total PCSK9 levels may provide a diagnostic tool for explaining an apparent resistance to PCSK9 inhibitors, thus indicating the need for other approaches. Newer agents targeting PCSK9 are in clinical development with a major interest in those with a longer duration of action, e.g. RNA silencing, allowing optimal patient compliance. Interest has been expanded to areas not only limited to low-density lipoprotein cholesterol reduction but also investigating other non-lipid pathways raising cardiovascular risk, in particular inflammation associated to raised high-sensitivity C-reactive protein levels, not significantly affected by the present PCSK9 antagonists.

Long-term exposure to air pollution raises circulating levels of proprotein convertase subtilisin/kexin type 9 in obese individuals

Aims

Exposure to airborne particulate matter has been consistently associated with early death and increased morbidity, particularly raising the risk of cardiovascular disease. Obesity, one of the leading cardiovascular disease risk factors, increases susceptibility to the adverse effects of particulate matter exposure. Proprotein convertase subtilisin/kexin type 9 has been related to a large number of cardiovascular risk factors, e.g. atherogenic lipoproteins, arterial stiffness and platelet activation. Thus, the present study was aimed at evaluating, in a series of obese individuals, the effects of particulate matter less than 10 µm in diameter (PM10) on proprotein convertase subtilisin/kexin type 9 circulating levels.

Methods and results

In 500 obese subjects, participating in the cross-sectional Susceptibility to Particle Health Effects, miRNAs and Exosomes (SPHERE) study, we evaluated the effects of long- and short-term PM10 exposure on circulating proprotein convertase subtilisin/kexin type 9 levels. In the studied individuals (body mass index: 33.3 ± 5.2 kg/m2) with an annual average PM10 exposure of 40.12 ± 4.71 µg/m3, proprotein convertase subtilisin/kexin type 9 levels were 248.7 ± 78.6 ng/mL. In univariate analysis, PM10 exposure (annual average) was associated with proprotein convertase subtilisin/kexin type 9 levels (β=1.83, standard error = 0.75, p = 0.014). Interestingly, in a multivariable linear regression model, this association was observed only for carriers of lower concentrations of interferon-γ, whereas it was lost in the presence of higher interferon-γ levels. Proprotein convertase subtilisin/kexin type 9 levels were positively associated with the Framingham Risk Score, which was raised by 15.8% for each 100 ng/ml rise of proprotein convertase subtilisin/kexin type 9.

Conclusions

In obese individuals, more sensitive to the damaging effects of environmental air pollution, PM10 exposure positively associates with proprotein convertase subtilisin/kexin type 9 plasma levels especially in those with low levels of interferon-γ. 

Effect of omega-3 supplements on plasma apolipoprotein C-III concentrations: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Apolipoprotein C-III (apo C-III) is a key regulator of triglycerides metabolism. The aim of this meta-analysis was to assess the effect of fish omega-3 polyunsaturated fatty acids (PUFAs) on apo C-III levels.

METHODS

Randomized placebo-controlled trials investigating the impact of omega-3 on apo C-III levels were searched in PubMed-Medline, SCOPUS, Web of Science and Google Scholar. A random-effects model and generic inverse variance method were used for quantitative data synthesis. Sensitivity analysis was conducted using the leave-one-out method. A weighted random-effects meta-regression was performed to evaluate the impact of potential confounders on glycemic parameters.

RESULTS

This meta-analysis comprising 2062 subjects showed a significant reduction of apo C-III concentrations following treatment with omega-3 (WMD: -22.18 mg/L, 95% confidence interval: -31.61, -12.75, p < .001; I²: 88.24%). Subgroup analysis showed a significant reduction of plasma apo C-III concentrations by eicosapentaenoic acid (EPA) ethyl esters but not omega-3 carboxylic acids or omega-3 ethyl esters. There was a greater apo C-III reduction with only EPA as compared with supplements containing EPA and docosahexaenoic acid (DHA) or only DHA. A positive association between the apo C-III-lowering effect of omega-3 with baseline apo C-III concentrations and treatment duration was found.

CONCLUSIONS

This meta-analysis has shown that omega-3 PUFAs might significantly decrease apo C-III. Key messages Omega-3 PUFA supplements significantly reduce apo C-III plasma levels, particularly in hypertriglyceridemic patients when applied in appropriate dose (more than 2 g/day) Triglyceride (TG)-lowering effect is achieved via peroxisome proliferator-activated receptors α Further studies should address the effect of omega-3 PUFAs alone or with other lipid-lowering drugs in order to provide a final answer whether apo C-III could be an important target for prevention of cardiovascular disease New apo C-III antisense oligonucleotide drug (Volanesorsen) showed to be promising in decreasing elevated TGs by reducing levels of apo C-III mRNA.

Effects of Vegetable Proteins on Hypercholesterolemia and Gut Microbiota Modulation

Risk assessment tools, i.e., validated risk prediction algorithms, to estimate the patient's 10-year risk of developing cardiovascular disease (CVD) should be used to identify high-risk people for primary prevention. Current evidence confirms that appropriate monitoring and control of risk factors either reduces the likelihood of CVD or slows down its progression. It is thus crucial that all health professionals make appropriate use of all the available intervention strategies to control risk factors: from dietary improvement and adequate physical activity to the use of functional foods, food supplements, and drugs. The gut microbiota, which encompasses 1 × 1014 resident microorganisms, has been recently recognized as a contributing factor in the development of human disease. This review examines the effect of both some vegetable food components belong to the "protein food group" and the underexploited protein-rich hempseed on cholesterolemia and gut microbiota composition.

Lipid lowering drugs and inflammatory changes: an impact on cardiovascular outcomes?

Inflammatory changes are responsible for maintenance of the atherosclerotic process and may underlie some of the most feared vascular complications. Among the multiple mechanisms of inflammation, the arterial deposition of lipids and particularly of cholesterol crystals is the one responsible for the activation of inflammasome NLRP3, followed by the rise of circulating markers, mainly C-reactive protein (CRP). Elevation of lipoproteins, LDL but also VLDL and remnants, associates with increased inflammatory changes and coronary risk. Lipid lowering medications can reduce cholesterolemia and CRP: patients with elevations of both are at greatest cardiovascular (CV) risk and receive maximum benefit from therapy. Evaluation of the major drug series indicates that statins exert the largest LDL and CRP reduction, accompanied by reduced CV events. Other drugs, mainly active on the triglyceride/HDL axis, for example, PPAR agonists, may improve CRP and the lipid pattern, especially in patients with metabolic syndrome. PCSK9 antagonists, the newest most potent medications, do not induce significant changes in inflammatory markers, but patients with the highest baseline CRP levels show the best CV risk reduction. Parallel evaluation of lipids and inflammatory changes clearly indicates a significant link, both guiding to patients at highest risk, and to the best pharmacological approach. Key messages Lipid lowering agents with "pleiotropic" effects provide a more effective approach to CV prevention In CANTOS study, patients achieving on-treatment hsCRP concentrations ≤2 mg/L had a higher benefit in terms of reduction in major CV events The anti-inflammatory activity of PCSK9 antagonists appears to be of a minimal extent.