Moving Targets: Recent Advances in Lipid-Lowering Therapies

LDL cholesterol targets rarely achieved in familial hypercholesterolemia patients: A sex and gender-specific analysis

BACKGROUND AND AIMS

Despite lipid lowering therapy (LLT), reaching LDL-C targets in patients with familial hypercholesterolemia (FH) remains challenging. Our aim was to determine attainment of LDL-C target levels and reasons for not reaching these in female and male FH patients.

METHODS

We performed a cross-sectional study of heterozygous FH patients in five hospitals in the Netherlands and Norway. Clinical characteristics and information about LLT, lipid levels and reasons for not being on LDL-C treatment target were retrospectively collected from electronic medical records.

RESULTS

We studied 3178 FH patients (53.9% women), median age 48.0 (IQR 34.0-59.9) years. Median LDL-C before treatment and on-treatment was higher in women compared to men (6.2 (IQR 5.1-7.3) and 6.0 (IQR 4.9-7.2) mmol/l (p=0.005) and 3.0 (IQR 2.4-3.8) and 2.8 (IQR 2.3-3.5) mmol/L (p<0.001)), respectively. A minority of women (26.9%) and men (28.9%) reached LDL-C target. In patients with CVD, 17.2% of women and 25.8% of men reached LDL-C target. Women received less often high-intensity statins and ezetimibe. Most common reported reasons for not achieving the LDL-C target were insufficient effect of maximum LLT (women 17.3%, men 24.3%) and side effects (women 15.2%, men 8.6%).

CONCLUSIONS

In routine practice, only a minority of women and men with FH achieved their LDL-C treatment target. Extra efforts have to be made to provide FH patients with reliable information on the safety of statins and their long-term effects on CVD risk reduction. If statin treatment is insufficient, alternative lipid lowering therapies such as ezetimibe or PCSK9-inhibitors should be considered.

Structure-based mechanism and inhibition of cholesteryl ester transfer protein

PURPOSE OF REVIEW

Cholesteryl ester transfer proteins (CETP) regulate plasma cholesterol levels by transferring cholesteryl esters (CEs) among lipoproteins. Lipoprotein cholesterol levels correlate with the risk factors for atherosclerotic cardiovascular disease (ASCVD). This article reviews recent research on CETP structure, lipid transfer mechanism, and its inhibition.

RECENT FINDINGS

Genetic deficiency in CETP is associated with a low plasma level of low-density lipoprotein cholesterol (LDL-C) and a profoundly elevated plasma level of high-density lipoprotein cholesterol (HDL-C), which correlates with a lower risk of atherosclerotic cardiovascular disease (ASCVD). However, a very high concentration of HDL-C also correlates with increased ASCVD mortality. Considering that the elevated CETP activity is a major determinant of the atherogenic dyslipidemia, i.e., pro-atherogenic reductions in HDL and LDL particle size, inhibition of CETP emerged as a promising pharmacological target during the past two decades. CETP inhibitors, including torcetrapib, dalcetrapib, evacetrapib, anacetrapib and obicetrapib, were designed and evaluated in phase III clinical trials for the treatment of ASCVD or dyslipidemia. Although these inhibitors increase in plasma HDL-C levels and/or reduce LDL-C levels, the poor efficacy against ASCVD ended interest in CETP as an anti-ASCVD target. Nevertheless, interest in CETP and the molecular mechanism by which it inhibits CE transfer among lipoproteins persisted. Insights into the structural-based CETP-lipoprotein interactions can unravel CETP inhibition machinery, which can hopefully guide the design of more effective CETP inhibitors that combat ASCVD. Individual-molecule 3D structures of CETP bound to lipoproteins provide a model for understanding the mechanism by which CETP mediates lipid transfer and which in turn, guide the rational design of new anti-ASCVD therapeutics.

Pharmacometabolomics for the Study of Lipid-Lowering Therapies: Opportunities and Challenges

Lipid-lowering therapies are widely used to prevent the development of atherosclerotic cardiovascular disease (ASCVD) and related mortality worldwide. "Omics" technologies have been successfully applied in recent decades to investigate the mechanisms of action of these drugs, their pleiotropic effects, and their side effects, aiming to identify novel targets for future personalized medicine with an improvement of the efficacy and safety associated with the treatment. Pharmacometabolomics is a branch of metabolomics that is focused on the study of drug effects on metabolic pathways that are implicated in the variation of response to the treatment considering also the influences from a specific disease, environment, and concomitant pharmacological therapies. In this review, we summarized the most significant metabolomic studies on the effects of lipid-lowering therapies, including the most commonly used statins and fibrates to novel drugs or nutraceutical approaches. The integration of pharmacometabolomics data with the information obtained from the other "omics" approaches could help in the comprehension of the biological mechanisms underlying the use of lipid-lowering drugs in view of defining a precision medicine to improve the efficacy and reduce the side effects associated with the treatment.

Lectin-Like Oxidized Low-Density Lipoprotein Receptor 1 Inhibition in Type 2 Diabetes: Phase 1 Results

Background Blockade of the lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a potentially attractive mechanism for lowering inflammatory and lipid risk in patients with atherosclerosis. This study aims to assess the safety, tolerability, and target engagement of MEDI6570, a high-affinity monoclonal blocking antibody to LOX-1. Methods and Results This phase 1, first-in-human, placebo-controlled study (NCT03654313) randomized 88 patients with type 2 diabetes to receive single ascending doses (10, 30, 90, 250, or 500 mg) or multiple ascending doses (90, 150, or 250 mg once monthly for 3 months) of MEDI6570 or placebo. Primary end point was safety; secondary and exploratory end points included pharmacokinetics, immunogenicity, free soluble LOX-1 levels, and change in coronary plaque volume. Mean age was 57.6/58.1 years in the single ascending doses/multiple ascending doses groups, 31.3%/62.5% were female, and mean type 2 diabetes duration was 9.7/8.7 years. Incidence of adverse events was similar among cohorts. MEDI6570 exhibited nonlinear pharmacokinetics, with terminal half-life increasing from 4.6 days (30 mg) to 11.2 days (500 mg), consistent with target-mediated drug disposition. Dose-dependent reductions in mean soluble LOX-1 levels from baseline were observed (>66% at 4 weeks and 71.61-82.96% at 10 weeks in the single ascending doses and multiple ascending doses groups, respectively). After 3 doses, MEDI6570 was associated with nonsignificant regression of noncalcified plaque volume versus placebo (-13.45 mm3 versus -8.25 mm3). Conclusions MEDI6570 was well tolerated and demonstrated dose-dependent soluble LOX-1 suppression and a pharmacokinetic profile consistent with once-monthly dosing. Registration URL: https://clinicaltrials.gov/; Unique identifier: NCT03654313.

miR-99a-5p: A Potential New Therapy for Atherosclerosis by Targeting mTOR and Then Inhibiting NLRP3 Inflammasome Activation and Promoting Macrophage Autophagy

Objective

MicroRNAs have been revealed to be involved in the development of atherosclerosis. The present study is aimed at exploring the potential of miR-99a-5p as a therapy for atherosclerosis. We suspected that miR-99a-5p might inhibit NLRP3 inflammasome activation and promote macrophage autophagy via constraining mTOR, therefore, alleviating atherosclerosis.

Methods

The cell viability in ox-LDL-induced THP-1 macrophages was assessed by CCK-8 assay. Bioinformatic analysis was used to predict the target genes of miR-99a-5p. The binding between miR-99a-5p and mTOR was confirmed by luciferase reporter assay. In vivo, a high-fat-diet-induced atherosclerosis model was established in apolipoprotein E knockout mice. Hematoxylin-eosin, oil red O, and Sirius red staining were performed for the determination of atherosclerotic lesions. MTOR and associated protein levels were detected by Western blot analysis.

Results

miR-99a-5p inhibited NLRP3 inflammasome activation and promoted macrophage autophagy by targeting mTOR. Enforced miR-99a-5p significantly reduced the levels of inflammasome complex and inflammatory cytokines. Furthermore, miR-99a-5p overexpression inhibited the expression of mTOR, whereas mTOR overexpression reversed the trend of the above behaviors. In vivo, the specific overexpression of miR-99a-5p significantly reduced atherosclerotic lesions, accompanied by a significant downregulation of autophagy marker CD68 protein expression.

Conclusion

We demonstrated for the first time that miR-99a-5p may be considered a therapy for atherosclerosis. The present study has revealed that miR-99a-5p might inhibit NLRP3 inflammasome activation and promote macrophage autophagy by targeting mTOR, therefore, alleviating atherosclerosis.

Inflammation and atherosclerosis: signaling pathways and therapeutic intervention

Atherosclerosis is a chronic inflammatory vascular disease driven by traditional and nontraditional risk factors. Genome-wide association combined with clonal lineage tracing and clinical trials have demonstrated that innate and adaptive immune responses can promote or quell atherosclerosis. Several signaling pathways, that are associated with the inflammatory response, have been implicated within atherosclerosis such as NLRP3 inflammasome, toll-like receptors, proprotein convertase subtilisin/kexin type 9, Notch and Wnt signaling pathways, which are of importance for atherosclerosis development and regression. Targeting inflammatory pathways, especially the NLRP3 inflammasome pathway and its regulated inflammatory cytokine interleukin-1β, could represent an attractive new route for the treatment of atherosclerotic diseases. Herein, we summarize the knowledge on cellular participants and key inflammatory signaling pathways in atherosclerosis, and discuss the preclinical studies targeting these key pathways for atherosclerosis, the clinical trials that are going to target some of these processes, and the effects of quelling inflammation and atherosclerosis in the clinic.

Hsp40s play distinct roles during the initial stages of apolipoprotein B biogenesis

Apolipoprotein B (ApoB) is the primary component of atherogenic lipoproteins, which transport serum fats and cholesterol. Therefore, elevated levels of circulating ApoB are a primary risk factor for cardiovascular disease. During ApoB biosynthesis in the liver and small intestine under nutrient-rich conditions, ApoB cotranslationally translocates into the endoplasmic reticulum (ER) and is lipidated and ultimately secreted. Under lipid-poor conditions, ApoB is targeted for ER Associated Degradation (ERAD). Although prior work identified select chaperones that regulate ApoB biogenesis, the contributions of cytoplasmic Hsp40s are undefined. To this end, we screened ApoB-expressing yeast and determined that a class A ER-associated Hsp40, Ydj1, associates with and facilitates the ERAD of ApoB. Consistent with these results, a homologous Hsp40, DNAJA1, functioned similarly in rat hepatoma cells. DNAJA1 deficient cells also secreted hyperlipidated lipoproteins, in accordance with attenuated ERAD. In contrast to the role of DNAJA1 during ERAD, DNAJB1-a class B Hsp40-helped stabilize ApoB. Depletion of DNAJA1 and DNAJB1 also led to opposing effects on ApoB ubiquitination. These data represent the first example in which different Hsp40s exhibit disparate effects during regulated protein biogenesis in the ER, and highlight distinct roles that chaperones can play on a single ERAD substrate.

Prenylcysteine oxidase 1, an emerging player in atherosclerosis

The research into the pathophysiology of atherosclerosis has considerably increased our understanding of the disease complexity, but still many questions remain unanswered, both mechanistically and pharmacologically. Here, we provided evidence that the pro-oxidant enzyme Prenylcysteine Oxidase 1 (PCYOX1), in the human atherosclerotic lesions, is both synthesized locally and transported within the subintimal space by proatherogenic lipoproteins accumulating in the arterial wall during atherogenesis. Further, Pcyox1 deficiency in Apoe^-/- mice retards atheroprogression, is associated with decreased features of lesion vulnerability and lower levels of lipid peroxidation, reduces plasma lipid levels and inflammation. PCYOX1 silencing in vitro affects the cellular proteome by influencing multiple functions related to inflammation, oxidative stress, and platelet adhesion. Collectively, these findings identify the pro-oxidant enzyme PCYOX1 as an emerging player in atherogenesis and, therefore, understanding the biology and mechanisms of all functions of this unique enzyme is likely to provide additional therapeutic opportunities in addressing atherosclerosis.

The Targeting of Native Proteins to the Endoplasmic Reticulum-Associated Degradation (ERAD) Pathway: An Expanding Repertoire of Regulated Substrates

All proteins are subject to quality control processes during or soon after their synthesis, and these cellular quality control pathways play critical roles in maintaining homeostasis in the cell and in organism health. Protein quality control is particularly vital for those polypeptides that enter the endoplasmic reticulum (ER). Approximately one-quarter to one-third of all proteins synthesized in eukaryotic cells access the ER because they are destined for transport to the extracellular space, because they represent integral membrane proteins, or because they reside within one of the many compartments of the secretory pathway. However, proteins that mature inefficiently are subject to ER-associated degradation (ERAD), a multi-step pathway involving the chaperone-mediated selection, ubiquitination, and extraction (or “retrotranslocation”) of protein substrates from the ER. Ultimately, these substrates are degraded by the cytosolic proteasome. Interestingly, there is an increasing number of native enzymes and metabolite and solute transporters that are also targeted for ERAD. While some of these proteins may transiently misfold, the ERAD pathway also provides a route to rapidly and quantitatively downregulate the levels and thus the activities of a variety of proteins that mature or reside in the ER.

Zebrafish as a Model for the Study of Lipid-Lowering Drug-Induced Myopathies

Drug-induced myopathies are classified as acquired myopathies caused by exogenous factors. These pathological conditions develop in patients without muscle disease and are triggered by a variety of medicaments, including lipid-lowering drugs (LLDs) such as statins, fibrates, and ezetimibe. Here we summarise the current knowledge gained via studies conducted using various models, such as cell lines and mammalian models, and compare them with the results obtained in zebrafish (Danio rerio) studies. Zebrafish have proven to be an excellent research tool for studying dyslipidaemias as a model of these pathological conditions. This system enables in-vivo characterization of drug and gene candidates to further the understanding of disease aetiology and develop new therapeutic strategies. Our review also considers important environmental issues arising from the indiscriminate use of LLDs worldwide. The widespread use and importance of drugs such as statins and fibrates justify the need for the meticulous study of their mechanism of action and the side effects they cause.

Regression in carotid plaque lipid content and neovasculature with PCSK9 inhibition: A time course study

BACKGROUND AND AIMS

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors reduce cardiovascular events, but their effects on atherosclerotic plaque remain elusive. Using serial magnetic resonance imaging (MRI), we studied changes in carotid plaque lipid content and neovasculature under PCSK9 inhibition with alirocumab.

METHODS

Among patients with low-density lipoprotein cholesterol (LDL-C) ≥70 mg/dl but ineligible for high-dose statin therapy, those with lipid core on carotid MRI were identified to receive alirocumab 150 mg every 2 weeks. Follow-up MRI was performed at 3, 6, and 12 months after treatment. Pre- and post-contrast MRI were acquired to measure percent lipid core volume (% lipid core). Dynamic contrast-enhanced MRI was acquired to measure the extravasation rate of gadolinium contrast (K^trans), a marker of plaque neovasculature.

RESULTS

Of 31 patients enrolled, 27 completed the study (mean age: 69 ± 9; male: 67%). From 9.8% at baseline, % lipid core was progressively reduced to 8.4% at 3 months, 7.5% at 6 months, and 7.2% at 12 months (p = 0.014 for trend), which was accompanied by a progressive increase in % fibrous tissue (p = 0.009) but not % calcification (p = 0.35). K^trans was not reduced until 12 months (from 0.069 ± 0.019 min^-1 to 0.058 ± 0.020 min^-1; p = 0.029). Lumen and wall areas did not change significantly during the study period.

CONCLUSIONS

Regression in plaque composition and neovasculature were observed under PCSK9 inhibition on carotid MRI, which provides unique insight into the biological process of plaque stabilization with disease-modifying therapies.

Treatment of mild-to-moderate hypertriglyceridemia

The atherogenic role of triglycerides (TG) as an independent cardiovascular risk factor has been discussed for many years, largely because hypertriglyceridaemia (HTG) is a complex metabolic entity of multiple aetiology involving processes of diverse nature. In this chapter, a discussion will be presented on the current recommendations for the management of mild-moderate hypertriglyceridaemia (150-880mg/dL). The aim of the interventions used is to decrease the LDL-cholesterol (c-LDL) and control the HTG. This entails reducing apoprotein B (ApoB) levels, the number of remaining TG-rich lipoproteins (LRP), non-HDL-cholesterol (c-non-HDL), and increasing HDL-cholesterol (c-HDL). The management strategy includes healthy lifestyle recommendations, and subsequent use of lipid-lowering drugs, including statins, fibrates, n-3 fatty acids and PCSK9 inhibitors.

Pineapple consumption reduced cardiac oxidative stress and inflammation in high cholesterol diet-fed rats

BACKGROUND

Hypercholesterolemia is a major risk factor for cardiovascular disease. It has been reported that pineapple contains healthy nutrients and phytochemicals associated with antioxidant and anti-inflammatory capacities. No investigation exists concerning the effect of pineapple consumption modulating hypercholesterolemia-induced cardiac damage in high-cholesterol diet (HCD)-fed rats. This study evaluated the effect of pineapple consumption on lipid-lowering, cardiac oxidative stress and inflammation in HCD-fed rats.

METHODS

Male Sprague-Dawley rats were fed with HCD, in the presence and absence of Pineapple (Ananas comosus L.) cv. Pattavia powder for 8 weeks. Then, serum lipid profiles, liver and renal function tests, cardiac oxidative stress and pro-inflammatory cytokines were determined.

RESULTS

Daily pineapple consumption reduced weight gain, serum lipid profiles, atherogenic coefficient (AC), cardiac risk ratio (CRR), and liver enzyme activity, without causing renal dysfunction. Pineapple consumption also restores cardiac protein carbonyl (cPC) content, reduces cardiac malondialdehyde (MDA), cardiac pro-inflammation cytokine IL-6 and IL-1β levels.

CONCLUSION

Pineapple possesses antioxidant and lipid-lowering properties and daily consumption alleviates hypercholesterolemia-induced cardiac lipid peroxidation and pro-inflammation elevation in an in vivo model. This study demonstrates that pineapple is a potential candidate for cardioprotection against hypercholesterolemia.

Novel therapies for familial hypercholesterolemia

PURPOSE OF REVIEW

Familial hypercholesterolemia is a genetic disorder of defective clearance and subsequent increase in serum LDL cholesterol (LDL-C) with a resultant increased risk of premature atherosclerotic cardiovascular disease. Despite treatment with traditional lipid-lowering therapies (LLT), most patients with familial hypercholesterolemia are unable to achieve target LDL-C. We review current and future novel therapeutic options available for familial hypercholesterolemia.

RECENT FINDINGS

The use of proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors are effective in lowering LDL-C in patients with familial hypercholesterolemia, with a reduction in LDL-C of 60% in heterozygous familial hypercholesterolemia (HeFH) and up to 35% in homozygous familial hypercholesterolemia (HoFH). Inclisiran, another novel agent, is a small-interfering ribonucleic acid that reduces hepatic production of PCSK9 to provide a prolonged and sustained reduction in LDL-C of nearly 50% in HeFH. However, both agents require LDL receptor (LDLR) activity. Evinacumab, a novel monoclonal antibody against angiopoetin-like 3 (ANGPTL3), reduces LDL-C by 50% independent of LDLR activity.

SUMMARY

Achieving a target LDL-C in familial hypercholesterolemia can be challenging with standard LLT; however, novel therapeutic modalities show remarkable reductions in LDL-C allowing nearly all patients with HeFH and a significant proportion of patients with HoFH to achieve acceptable LDL-C levels.

Hypertriglyceridemia: new approaches in management and treatment

PURPOSE OF REVIEW

Hypertriglyceridemia (HTG), a form of dyslipidemia characterized by elevated plasma of triglycerides (TG), is associated with an increased risk for acute pancreatitis. Moreover, HTG has recently been shown to be linked to the development of atherosclerotic cardiovascular disease (ASCVD); therefore, there is a great interest in better understanding the pathophysiology of HTG and improving its clinical management. In this review, we briefly describe TG metabolism, recent guidelines for the clinical management of HTG and provide an overview of the current and potential new therapies for HTG.

RECENT FINDINGS

Screening patients for HTG is valuable for not only identifying patients with extreme TG elevations, who are at risk for pancreatitis, but also for managing ASCVD risk in patients with more moderate forms of HTG. Therefore, the most recent USA guidelines for cardiovascular diseases recommend using TG as a risk enhancer test, leading to a more aggressive treatment of patients with intermediate risk. Currently, there are several available approaches for reducing plasma TG, which include lifestyle changes, fibrates and omega-3 fatty acid treatment. The addition of eicosapentaenoic acid (EPA) on top of statins has recently been shown to significantly reduce ASCVD events. Nevertheless, there is an unmet need for more effective treatment options. Several new therapies based on newly identified targets in TG metabolism, such as apolipoprotein C-III and angiopoietin-like 3 protein, are currently under development.

SUMMARY

The clinical management of HTG is important in the prevention and treatment of acute pancreatitis and also impacts on how ASCVD risk is managed. More work needs to be done to establish the mechanism for the ability of how EPA lowers ASCVD and how to best integrate it with other lipid-lowering therapies. The efficacy and safety of the novel therapies for HTG should be established soon in the ongoing late-stage clinical trials.

A dual apolipoprotein C-II mimetic-apolipoprotein C-III antagonist peptide lowers plasma triglycerides

Recent genetic studies have established that hypertriglyceridemia (HTG) is causally related to cardiovascular disease, making it an active area for drug development. We describe a strategy for lowering triglycerides (TGs) with an apolipoprotein C-II (apoC-II) mimetic peptide called D6PV that activates lipoprotein lipase (LPL), the main plasma TG-hydrolyzing enzyme, and antagonizes the TG-raising effect of apoC-III. The design of D6PV was motivated by a combination of all-atom molecular dynamics simulation of apoC-II on the Anton 2 supercomputer, structural prediction programs, and biophysical techniques. Efficacy of D6PV was assessed ex vivo in human HTG plasma and was found to be more potent than full-length apoC-II in activating LPL. D6PV markedly lowered TG by more than 80% within a few hours in both apoC-II-deficient mice and hAPOC3-transgenic (Tg) mice. In hAPOC3-Tg mice, D6PV treatment reduced plasma apoC-III by 80% and apoB by 65%. Furthermore, low-density lipoprotein (LDL) cholesterol did not accumulate but rather was decreased by 10% when hAPOC3-Tg mice lacking the LDL-receptor (hAPOC3-Tg × Ldlr^-/- ) were treated with the peptide. D6PV lowered TG by 50% in whole-body inducible Lpl knockout (iLpl^-/- ) mice, confirming that it can also act independently of LPL. D6PV displayed good subcutaneous bioavailability of about 80% in nonhuman primates. Because it binds to high-density lipoproteins, which serve as a long-term reservoir, it also has an extended terminal half-life (42 to 50 hours) in nonhuman primates. In summary, D6PV decreases plasma TG by acting as a dual apoC-II mimetic and apoC-III antagonist, thereby demonstrating its potential as a treatment for HTG.

A Brief Review of Cardiovascular Diseases, Associated Risk Factors and Current Treatment Regimes

Cardiovascular diseases (CVDs) are the leading cause of premature death and disability in humans and their incidence is on the rise globally. Given their substantial contribution towards the escalating costs of health care, CVDs also generate a high socio-economic burden in the general population. The underlying pathogenesis and progression associated with nearly all CVDs are predominantly of atherosclerotic origin that leads to the development of coronary artery disease, cerebrovascular disease, venous thromboembolism and, peripheral vascular disease, subsequently causing myocardial infarction, cardiac arrhythmias or stroke. The aetiological risk factors leading to the onset of CVDs are well recognized and include hyperlipidaemia, hypertension, diabetes, obesity, smoking and, lack of physical activity. They collectively represent more than 90% of the CVD risks in all epidemiological studies. Despite high fatality rate of CVDs, the identification and careful prevention of the underlying risk factors can significantly reduce the global epidemic of CVDs. Beside making favorable lifestyle modifications, primary regimes for the prevention and treatment of CVDs include lipid-lowering drugs, antihypertensives, antiplatelet and anticoagulation therapies. Despite their effectiveness, significant gaps in the treatment of CVDs remain. In this review, we discuss the epidemiology and pathology of the major CVDs that are prevalent globally. We also determine the contribution of well-recognized risk factors towards the development of CVDs and the prevention strategies. In the end, therapies for the control and treatment of CVDs are discussed.

A potent risk model for predicting new-onset acute coronary syndrome in patients with type 2 diabetes mellitus in Northwest China

AIMS

Type 2 diabetes mellitus (T2DM) is now very prevalent in China. Due to the lower rate of controlled diabetes in China compared to that in developed countries, there is a higher incidence of serious cardiovascular complications, especially acute coronary syndrome (ACS). The aim of this study was to establish a potent risk predictive model in the economically disadvantaged northwest region of China, which could predict the probability of new-onset ACS in patients with T2DM.

METHODS

Of 456 patients with T2DM admitted to the First Affiliated Hospital of Xi'an Jiaotong University from January 2018 to January 2019 and included in this study, 270 had no ACS, while 186 had newly diagnosed ACS. Overall, 32 demographic characteristics and serum biomarkers of the study patients were analysed. The least absolute shrinkage and selection operator regression was used to select variables, while the multivariate logistic regression was used to establish the predictive model that was presented using a nomogram. The area under the receiver operating characteristics curve (AUC) was used to evaluate the discriminatory capacity of the model. A calibration plot and Hosmer-Lemeshow test were used for the calibration of the predictive model, while the decision curve analysis (DCA) was used to evaluate its clinical validity.

RESULTS

After random sampling, 319 and 137 T2DM patients were included in the training and validation sets, respectively. The predictive model included age, body mass index, diabetes duration, systolic blood pressure (SBP), diastolic blood pressure (DBP), low-density lipoprotein cholesterol, serum uric acid, lipoprotein(a), hypertension history and alcohol drinking status as predictors. The AUC of the predictive model and that of the internal validation set was 0.830 [95% confidence interval (CI) 0.786-0.874] and 0.827 (95% CI 0.756-0.899), respectively. The predictive model showed very good fitting degree, and DCA demonstrated a clinically effective predictive model.

CONCLUSIONS

A potent risk predictive model was established, which is of great value for the secondary prevention of diabetes. Weight loss, lowering of SBP and blood uric acid levels and appropriate control for DBP may significantly reduce the risk of new-onset ACS in T2DM patients in Northwest China.

Apolipoprotein C-II: the re-emergence of a forgotten factor

PURPOSE OF REVIEW

Apolipoprotein C-II (apoC-II) is a critical cofactor for the activation of lipoprotein lipase (LPL), a plasma enzyme that hydrolyzes triglycerides (TG) on TG-rich lipoproteins (TRL). Although apoC-II was first discovered nearly 50 years ago, there is renewed interest in it because of the recent efforts to develop new drugs for the treatment of hypertriglyceridemia (HTG). The main topic of this review will be the development of apoC-II mimetic peptides as a possible new therapy for cardiovascular disease.

RECENT FINDINGS

We first describe the biochemistry of apoC-II and its role in TRL metabolism. We then review the clinical findings of HTG, particularly those related to apoC-II deficiency, and how TG metabolism relates to the development of atherosclerosis. We next summarize the current efforts to develop new drugs for HTG. Finally, we describe recent efforts to make small synthetic apoC-II mimetic peptides for activation of LPL and how these peptides unexpectedly have other mechanisms of action mostly related to the antagonism of the TG-raising effects of apoC-III.

SUMMARY

The role of apoC-II in TG metabolism is reviewed, as well as recent efforts to develop apoC-II mimetic peptides into a novel therapy for HTG.

Long-Term Outcomes After Revascularization for Stable Ischemic Heart Disease: An Individual Patient-Level Pooled Analysis of 19 Randomized Coronary Stent Trials

BACKGROUND

Whether revascularization improves prognosis in stable ischemic heart disease is controversial.

METHODS

Individual patient-level data from 19 prospective, randomized stent trials were pooled. Rates of 5-year major adverse cardiovascular events (MACE; a composite of cardiac death, myocardial infarction, or ischemia-driven target lesion revascularization) were assessed and compared after percutaneous coronary intervention with bare-metal stents (BMS) and first-generation and second-generation drug-eluting stents (DES1 and DES2, respectively). Poisson multivariable regression analysis was performed to identify predictors of adverse events.

RESULTS

Among 10 987 patients treated with percutaneous coronary intervention for stable ischemic heart disease, 1550, 2776, and 6661 received BMS, DES1, and DES2, respectively. The 5-year rates of MACE progressively declined with evolution in stent technology (BMS: 24.1% versus DES1: 17.9% versus DES2: 13.4%, P<0.0001). However, MACE rates between 1 and 5 years increased from BMS to DES1, then declined with DES2 (BMS: 7.4% versus DES1: 10.2%, DES2: 8.5%, P=0.02).

CONCLUSIONS

Patients with stable ischemic heart disease remain at substantial risk for long-term MACE after revascularization with percutaneous coronary intervention, even with contemporary DES. New approaches to reduce the ongoing risk of MACE beyond 1 year after stent implantation are necessary.

Familial Hypercholesterolaemia in 2020: A Leading Tier 1 Genomic Application

Familial hypercholesterolaemia (FH) is caused by a major genetic defect in the low-density lipoprotein (LDL) clearance pathway. Characterised by LDL-cholesterol elevation from birth, FH confers a significant risk for premature coronary artery disease (CAD) if overlooked and untreated. With risk exposure beginning at birth, early detection and intervention is crucial for the prevention of CAD. Lowering LDL-cholesterol with lifestyle and statin therapy can reduce the risk of CAD. However, most individuals with FH will not reach guideline recommended LDL-cholesterol targets. FH has an estimated prevalence of approximately 1:250 in the community. Multiple strategies are required for screening, diagnosing and treating FH. Recent publications on FH provide new data for developing models of care, including new therapies. This review provides an overview of FH and outlines some recent advances in the care of FH for the prevention of CAD in affected families. The future care of FH in Australia should be developed within the context of the National Health Genomics Policy Framework.

NAFLD and Atherosclerosis: Two Sides of the Same Dysmetabolic Coin?

The prevalence of non-alcoholic fatty liver disease (NAFLD) is strongly increasing and may put patients at increased risk for atherosclerotic cardiovascular disease (asCVD). Both disease phenotypes often co-occur, in the case of obesity, insulin resistance, diabetes mellitus type 2, and the metabolic syndrome. We explore the pathogenesis of NAFLD, the epidemiology of asCVD in NAFLD patients, shared drivers of both phenotypes, and factors caused by NAFLD that contribute to asCVD. Genetic studies support that NAFLD may drive asCVD through mixed hyperlipidemia. Next, we discuss the prospects of lifestyle improvement and pharmacological treatment of NAFLD for asCVD risk reduction. Finally, we point out that earlier identification of patients with NAFLD should be pursued by increasing awareness of the association of these two phenotypes and collaboration between the involved physicians.

Macrophages in Atherosclerosis Regression

Macrophages play a central role in the development of atherosclerotic cardiovascular disease (ASCVD), which encompasses coronary artery disease, peripheral artery disease, cerebrovascular disease, and aortic atherosclerosis. In each vascular bed, macrophages contribute to the maintenance of the local inflammatory response, propagate plaque development, and promote thrombosis. These central roles, coupled with their plasticity, makes macrophages attractive therapeutic targets in stemming the development of and stabilizing existing atherosclerosis. In the context of ASCVD, classically activated M1 macrophages initiate and sustain inflammation, and alternatively activated M2 macrophages resolve inflammation. However, this classification is now considered an oversimplification, and a greater understanding of plaque macrophage physiology in ASCVD is required to aid in the development of therapeutics to promote ASCVD regression. Reviewed herein are the macrophage phenotypes and molecular regulators characteristic of ASCVD regression, and the current murine models of ASCVD regression.

Low-Density Lipoprotein Cholesterol After an Acute Coronary Syndrome: How Low to Go?

PURPOSE OF REVIEW

Recent advances in low-density lipoprotein cholesterol (LDL-C) lowering therapy have now enabled reducing LDL-C safely to very low levels. This review summarizes evidence from recent randomized clinical trials of intensive LDL-C lowering in patients with acute coronary syndrome (ACS) and provides a practical approach for LDL-C lowering to reduce the risk of recurrent ischemic events in this population.

RECENT FINDINGS

The risk of atherothrombotic events falls linearly with LDL-C level extending to very low achieved LDL-C levels (< 10 mg/dL) without apparent safety concerns. The addition of ezetimibe or proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors (i.e., evolocumab or alirocumab) to statin therapy lowers LDL-C to very low levels (≤ 30-50 mg/dL) with safety under the conditions studied and reduces the risk of recurrent cardiovascular events in patients with atherosclerotic cardiovascular disease. Current data support LDL-C lowering to levels below 70 mg/dL in patients post-ACS. Combination of high-intensity statins, ezetimibe, and if needed PCSK9 inhibitors merits consideration in such patients with ACS to optimize outcomes.

Novel Antiatherosclerotic Therapies

Many measures can control lipid risk factors for atherosclerosis. Yet, even with excellent control of dyslipidemia, other sources of risk remain. Hence, we must look beyond lipids to address residual risk. Lifestyle measures should form the foundation of cardiovascular risk control. Many pharmacological interventions targeting oxidation have proven disappointing. A large program tested inhibition of a LpPLA2 (lipoprotein-associated phospholipase A2), culminating in 2 large-scale clinical trials that did not meet their primary end points. A variety of antioxidants have not shown benefit in clinical trials. Numerous laboratory and clinical studies have inculpated inflammatory pathways in the pathogenesis of atherosclerotic events. The p38 MAPK (mitogen-activated protein kinase) inhibitor losmapimod and an inhibitor of a leukocyte adhesion molecule, P-selectin, did not alter adverse events in trials. Low-dose methotrexate, despite the promising observational studies, did not lower biomarkers of inflammation or alter cardiovascular outcomes in the CIRT (cardiovascular inflammation reduction trial). Four large-scale investigations underway will determine colchicine's ability to reduce recurrent events in secondary prevention. The CANTOS (Canakinumab Anti-inflammatory Thrombosis Outcomes Study) showed that an antibody that neutralizes IL (interleukin)-1β can reduce recurrent cardiovascular events in secondary prevention. The success of CANTOS points to the pathway that leads from the NLRP3 (NOD-like receptor family, pyrin domain-containing protein 3) inflammasome through IL-1β to IL-6 as an attractive target for further study and clinical development beyond lipid therapies to address the unacceptable burden of risk that remains despite our best current care in secondary prevention.