RNA Silencing in the Management of Dyslipidemias

Dyslipidaemia management in pregnant patients: a 2024 update

Over several decades, the approach to treating dyslipidaemias during pregnancy remains essentially unchanged. The lack of advancement in this field is mostly related to the fact that we lack clinical trials of pregnant patients both with available as well as new therapies. While there are numerous novel therapies developed for non-pregnant patients, there are still many limitations in dyslipidaemia treatment during pregnancy. Besides pharmacotherapy and careful clinical assessment, the initiation of behavioural modifications as well as pre-conception management is very important. Among the various lipid-lowering medications, bile acid sequestrants are the only ones officially approved for treating dyslipidaemia in pregnancy. Ezetimibe and fenofibrate can be considered if their benefits outweigh potential risks. Statins are still considered contraindicated, primarily due to animal studies and human case reports. However, recent systematic reviews and meta-analyses as well as data on familial hypercholesterolaemia (FH) in pregnant patients have indicated that their use may not be harmful and could even be beneficial in certain selected cases. This is especially relevant for pregnant patients at very high cardiovascular risk, such as those who have already experienced an acute cardiovascular event or have homozygous or severe forms of heterozygous FH. In these cases, the decision to continue therapy during pregnancy should weigh the potential risks of discontinuation. Bempedoic acid, olezarsen, evinacumab, evolocumab and alirocumab, and inclisiran are options to consider just before and after pregnancy is completed. In conclusion, decisions regarding lipid-lowering therapy for pregnant patients should be personalized. Despite the challenges in designing and conducting studies in pregnant women, there is a strong need to establish the safety and efficacy of dyslipidaemia treatment during pregnancy.

Novel roles of PIWI proteins and PIWI-interacting RNAs in human health and diseases

Non-coding RNA has aroused great research interest recently, they play a wide range of biological functions, such as regulating cell cycle, cell proliferation, and intracellular substance metabolism. Piwi-interacting RNAs (piRNAs) are emerging small non-coding RNAs that are 24-31 nucleotides in length. Previous studies on piRNAs were mainly limited to evaluating the binding to the PIWI protein family to play the biological role. However, recent studies have shed more lights on piRNA functions; aberrant piRNAs play unique roles in many human diseases, including diverse lethal cancers. Therefore, understanding the mechanism of piRNAs expression and the specific functional roles of piRNAs in human diseases is crucial for developing its clinical applications. Presently, research on piRNAs mainly focuses on their cancer-specific functions but lacks investigation of their expressions and epigenetic modifications. This review discusses piRNA's biogenesis and functional roles and the recent progress of functions of piRNA/PIWI protein complexes in human diseases. Video Abstract.

Bempedoic acid in the management of lipid disorders and cardiovascular risk. 2023 position paper of the International Lipid Expert Panel (ILEP)

Cardiovascular disease (CVD) is a chronic non-communicable disease (NCD) and the predominant cause of morbidity and mortality worldwide. Substantial reductions in the CVD prevalence have been achieved in recent years by the attenuation of risk factors (particularly hypertension and dyslipidaemias) in primary and secondary prevention. Despite the remarkable success of lipid lowering treatments, and of statins in particular, in reducing the risk of CVD, there is still an unmet clinical need for the attainment of guideline lipid-targets in even 2/3 of patients. Bempedoic acid, the first in-class inhibitor of ATP-citrate lyase presents a new approach to lipid-lowering therapy. By reducing the endogenous production of cholesterol, upstream of the rate-limiting enzyme HMG-CoA-reductase, i.e., the target of statins, bempedoic acid reduces circulating plasma concentrations of low-density lipoprotein cholesterol (LDL-C), and major adverse CVD events (MACE). Bempedoic acid has the potential to contribute to the reduction of CVD risk not only as monotherapy, but even further as part of a lipid-lowering combination therapy with ezetimibe, reducing LDL-C cholesterol up to 40%. This position paper of the International Lipid Expert Panel (ILEP) summarises the recent evidence around the efficacy and safety of bempedoic acid and presents practical recommendations for its use, which complement the 'lower-is-better-for-longer' approach to lipid management, which is applied across international guidelines for the management of CVD risk. Practical evidence-based guidance is provided relating to the use of bempedoic acid in atherosclerotic CVD, familial hypercholesterolaemia, and statin intolerance. Although there are still no sufficient data avilable for the role of bempedoic acid in the primary prevention of CVD, its favourable effects on plasma glucose and inflammatory markers makes this drug a rational choice in the patient-centred care of specific groups of primary prevention.

Management of Statin Intolerant Patients in the Era of Novel Lipid Lowering Therapies: A Critical Approach in Clinical Practice

Statins are the cornerstone of lipid-lowering therapies effective for cardiovascular risk reduction. Although they are generally well tolerated, statin intolerance (SI) is frequent in clinical practice, and it is usually related to the onset of muscle symptoms, which are defined under the acronym SAMS (Statin-Associated Muscle Side Effects). These side effects are responsible for statin treatment discontinuation that results in increased cardiovascular risk. The National Lipid Association (NLA) has recently provided an updated definition of statin intolerance, and a distinction between complete and partial statin intolerance has been reported. The evaluation of symptom severity and the presence of muscle damage biomarker alterations make it essential to adopt a patient-centered approach aimed at obtaining a personalized therapeutic strategy. Firstly, it could be useful to administer a different statin, reduce the dosage or adopt an alternate dosage regimen. However, some patients are unable to tolerate any statin at every dosage, or despite taking statins at the maximum tolerated dose, they fail to achieve the recommended LDL-C target, and thus it is necessary to introduce a non-statin hypolipidemic treatment. Ezetimibe, proprotein-convertase subtilisin/kexin type 9 (PCSK9) inhibitors such as monoclonal antibodies (alirocumab and evolocumab) or RNA messenger silencing (inclisiran), bempedoic acid or nutraceuticals are non-statin lipid-lowering therapies that could be used as an alternative or in addition to statins to achieve an early and sustained LDL-C reduction in clinical practice. In this review, we evaluated SI management focusing on non-statin lipid lowering therapies and their implications in lipid lowering approaches in clinical practice.

Recent Advances on the Roles of PCSK-9 Inhibitors in the Management of Acute Ischemic Stroke Patients

Acute ischemic stroke (AIS) represents an important cause of disability and death. Since only a minor percentage of patients with AIS are eligible for acute therapy, the management of risk factors is mandatory. An important risk factor of AIS is hyperlipemia. The current guidelines recommend a strict correction of it. Statins are recommended as the first-line treatment, while proprotein convertase subtilin/kexin type 9 (PCSK-9) inhibitors are administered as a second or even third option when the goal for a low-density lipoprotein cholesterol (LDL-C) level is not achieved. PCSK-9 inhibitors effectively decrease the LDL-C levels through the inhibition of PCSK-9-LDL-receptor complex formation. The in-depth understanding of the PCSK-9 protein mechanism in the metabolism of LDL-C led to the development of effective targeted approaches. Furthermore, a better understanding of the LDL-C metabolic pathway led to the development of newer approaches, which increased the therapeutic options. This article aims to offer an overview of the PCSK-9 inhibitors and their mechanism in reducing the LDL-C levels. Moreover, we will present the main indications of the current guidelines for patients with hyperlipemia and for those who have suffered an acute ischemic stroke, as well as the importance of LDL-C reduction in decreasing the rate of a recurrence.

New and Emerging Therapies for Dyslipidemia

Atherosclerotic cardiovascular disease (ASCVD) continues to represent a growing global health challenge. Despite guideline-recommended treatment of ASCVD risk, including antihypertensive, high-intensity statin therapy, and antiaggregant agents, high-risk patients, especially those with established ASCVD and patients with type 2 diabetes, continue to experience cardiovascular events. Recent years have brought significant developments in lipid and atherosclerosis research. Several lipid drugs owe their existence, in part, to human genetic evidence. Here, the authors briefly review the mechanisms, the effect on lipid parameters, and safety profiles of some of the most promising new lipid-lowering approaches that will be soon available in our daily clinical practice.

Low-density lipoprotein particles in atherosclerosis

Among the diseases causing human death, cardiovascular disease (CVD) remains number one according to the World Health Organization report in 2021. It is known that atherosclerosis is the pathological basis of CVD. Low-density lipoprotein (LDL) plays a pivotal role in the initiation and progression of atherosclerotic CVD (ASCVD). LDL cholesterol (LDL-C) is the traditional biological marker of LDL. However, large numbers of patients who have achieved the recommended LDL-C goals still have ASCVD risk. In multiple prospective studies, LDL particle (LDL-P) is reported to be more accurate in predicting CVD risk than LDL-C. LDL-Ps differ in size, density and chemical composition. Numerous clinical studies have proved that the atherogenic mechanisms of LDL-Ps are determined not only by LDL number and size but also by LDL modifications. Of note, small dense LDL (sdLDL) particles possess stronger atherogenic ability compared with large and intermediate LDL subfractions. Besides, oxidized LDL (ox-LDL) is another risk factor in atherosclerosis. Among the traditional lipid-lowering drugs, statins induce dramatic reductions in LDL-C and LDL-P to a lesser extend. Recently, proprotein convertase subtilsin/kexin type 9 inhibitors (PCSK9i) have been demonstrated to be effective in lowering the levels of LDL-C, LDL-P, as well as CVD events. In this article, we will make a short review of LDL metabolism, discuss the discordance between LDL-C and LDL-P, outline the atherogenic mechanisms of action of LDL by focusing on sdLDL and ox-LDL, summarize the methods used for measurement of LDL subclasses, and conclude the advances in LDL-lowering therapies using statins and PCSK9i.

The role of inflammation and the possibilities of inflammation reduction to prevent cardiovascular events

Chronic systemic inflammation is a risk factor for cardiovascular (CV) disease (CVD). Whether this relationship extends to subclinical inflammation, quantified by values of circulating markers associated with inflammation in the high range of the normal interval, remains debatable. This narrative review evaluates evidence exploring this relationship. A review of pharmacological and non-pharmacological interventions, including diet and lifestyle strategies, supplements, nutraceuticals, and other natural substances aimed at reducing inflammation was also conducted, since few reviews have synthesized this literature. PubMed and EMBASE were used to search the literature and several well-studied triggers of inflammation [oxidized LDL, Lp(a), as well as C-reactive protein (CRP)/high-sensitivity CRP (hs-CRP)] were included to increase sensitivity and address the lack of existing reviews summarizing their influence in the context of inflammation. All resulting references were assessed. Overall, there is good data supporting associations between circulating hs-CRP and CV outcomes. However, the same was not seen in studies evaluating triggers of inflammation, such as oxidized LDL or Lp(a). There is also insufficient evidence showing treatments to target inflammation and lead to reductions in hs-CRP result in improvements in CV outcomes, particularly in those with normal baseline levels of hs-CRP. Regarding pharmacological interventions, statins, bempedoic acid, and apabetalone significantly reduce circulating hs-CRP, unlike PCSK-9 inhibitors. A variety of natural substances and vitamins were also evaluated and none reduced hs-CRP. Regarding non-pharmacological interventions, weight loss was strongly associated with reductions in circulating hs-CRP, whereas various dietary interventions and exercise regimens were not, unless accompanied by weight loss.

NLA scientific statement on statin intolerance: a new definition and key considerations for ASCVD risk reduction in the statin intolerant patient

Although statins are generally well tolerated, statin intolerance is reported in 5-30% of patients and contributes to reduced statin adherence and persistence, as well as higher risk for adverse cardiovascular outcomes. This Scientific Statement from the National Lipid Association was developed to provide an updated definition of statin intolerance and to inform clinicians and researchers about its identification and management. Statin intolerance is defined as one or more adverse effects associated with statin therapy which resolves or improves with dose reduction or discontinuation and can be classified as a complete inability to tolerate any dose of a statin or partial intolerance with inability to tolerate the dose necessary to achieve the patient-specific therapeutic objective. To classify a patient as having statin intolerance, a minimum of two statins should have been attempted, including at least one at the lowest approved daily dosage. This Statement acknowledges the importance of identifying modifiable risk factors for statin intolerance and recognizes the possibility of a "nocebo" effect (patient expectation of harm resulting in perceived side effects). To identify a tolerable statin regimen it is recommended that clinicians consider using several different strategies (e.g., different statin, dose, and/or dosing frequency). Non-statin therapy may be required for patients who cannot reach therapeutic objectives with lifestyle and maximal tolerated statin therapy. If so, therapies with outcomes data from randomized trials showing reduced cardiovascular events are favored. In high and very high risk patients who are statin intolerant, clinicians should consider initiating non-statin therapy while additional attempts are made to identify a tolerable statin in order to limit the time of exposure to elevated levels of atherogenic lipoproteins.

Dyslipidemia Management in Pregnancy: Why Is It not Covered in the Guidelines?

PURPOSE OF REVIEW

Despite the elevation of lipid values during pregnancy is mostly physiological, evidence suggest that it may be associated with adverse events. This article reviews the characteristics of lipid disorders and the possible management with dyslipidemia in pregnant women.

RECENT FINDINGS

Among many available groups of lipid-lowering drugs, only bile acid sequestrants are approved for the treatment of dyslipidemia during pregnancy. Ezetimibe and fenofibrate might be considered if benefits outweigh the potential risk. Statins are still contraindicated due to the results mainly from animal studies and series of human cases. However, recent systematic reviews and meta-analyses showed that their use may not be detrimental, and in some selected cases may be beneficial. Especially, in some groups of pregnant patients with very high cardiovascular risk-those already after an event, or with established cardiovascular disease, with homozygous familial hypercholesterolemia; in such cases the final decision should weight the potential risk of discontinuation of therapy. Finally, we need to wait for the data with new drugs, including PCSK9 inhibitors and especially inclisiran, which (still hypothetically) might be a very interesting option as it may be used just before the pregnancy and immediately after with the duration of about 9 months between injections. The decisions on lipid-lowering therapy in pregnant patients should be individualized. Despite design and ethical difficulties with such studies, further investigations on dyslipidemia treatment during pregnancy are highly awaited.

Which patients at risk of cardiovascular disease might benefit the most from inclisiran? Polish experts' opinion. The compromise between EBM and possibilities in healthcare

It is the statement of the Polish Experts on the group of patients that might benefit the most from inclisiran. We indicated the fastest way to have inclisiran available for the polish patients, with the necessary changes of the existing drug program for PCSK9 inhibitors (B-101), explaining why it is the optimal way, and why, taking into account available EBM data (the ORION program), inclisiran should be added to this program. We also present some perspective on the future necessary changes in the availability of the innovative therapies such us PCSK9 targeted therapy, what, taking into account the effectiveness of LDL-C goal achievement in Poland for very high CVD risk patients (only 17%), seems to be critically important. Obviously it needs to be combined with our continuous attempts to improve the effectiveness and therapy adherence to available cheap therapy with statins and ezetimibe.

New technology in the hypolipidemic drugs development. Inclisiran (LEQVIO)

The development of lipid modifying drugs was expanding during the past 30 years. Statins stay to be the first choice drugs in dyslipidemia treatment. Inhibitors of proprotein convertase subtilisin- kexin type 9 (PCSK9) enzyme in combination with statin and/or ezetimibe represent very effective therapy and better atherosclerotic cardiovascular disease (ASCVD) prevention. Antisense therapy based on oligonucleotides belongs to the new technology drugs. This therapy inhibits translation of some proteins important for the production of atherogenic lipid particles. Inclisiran is a small interfering RNA that suppresses translation of PCSK9 in the liver cells. It is applied subcutaneously twice a year and it represents a big chance for the improvement of ASCVD treatment and prevention.

PCSK9 Inhibitor Wars: How Does Inclisiran Fit in with Current Monoclonal Antibody Inhibitor Therapy? Considerations for Patient Selection

PURPOSE OF REVIEW

Treatment of dyslipidemia represents one of the most crucial strategies to reduce risk of atherosclerotic cardiovascular (CV) disease (ASCVD). In this review, we critically summarize our knowledge on emerging cholesterol-lowering therapy, targeting PCSK9, paying particular attention on treatment allocation of two drug groups, currently available for clinical use, namely, anti-PCSK9 monoclonal antibodies (mAbs) and inclisiran, a first-in-class small interfering RNA against PCSK9.

RECENT FINDINGS

Although both drug classes show a pronounced, but fairly similar reduction in LDL-cholesterol, their long-term safety is still unknown. Compared to mAbs, inclisiran has a more favorable dosing regimen with biannual application that might improve therapeutic adherence significantly. However, a CV outcome trial (CVOT) for inclisiran is still missing. If inclisiran will be safe and effective in ongoing/future CVOTs, it has a huge potential to overcome medication non-compliance, thereby providing a powerful therapeutic option to decrease the burden of ASCVD.

CRISPR Gene Editing in Lipid Disorders and Atherosclerosis: Mechanisms and Opportunities

Elevated circulating concentrations of low-density lipoprotein cholesterol (LDL-C) have been conclusively demonstrated in epidemiological and intervention studies to be causally associated with the development of atherosclerotic cardiovascular disease. Enormous advances in LDL-C reduction have been achieved through the use of statins, and in recent years, through drugs targeting proprotein convertase subtilisin/kexin type 9 (PCSK9), a key regulator of the hepatic LDL-receptor. Existing approaches to PCSK9 targeting have used monoclonal antibodies or RNA interference. Although these approaches do not require daily dosing, as statins do, repeated subcutaneous injections are nevertheless necessary to maintain effectiveness over time. Recent experimental studies suggest that clustered regularly interspaced short palindromic repeats (CRISPR) gene-editing targeted at PCSK9 may represent a promising tool to achieve the elusive goal of a 'fire and forget' lifelong approach to LDL-C reduction. This paper will provide an overview of CRISPR technology, with a particular focus on recent studies with relevance to its potential use in atherosclerotic cardiovascular disease.

Chitosan Oleate Coated PLGA Nanoparticles as siRNA Drug Delivery System

Oligonucleotide therapeutics such as miRNAs and siRNAs represent a class of molecules developed to modulate gene expression by interfering with ribonucleic acids (RNAs) and protein synthesis. These molecules are characterized by strong instability and easy degradation due to nuclease enzymes. To avoid these drawbacks and ensure efficient delivery to target cells, viral and non-viral vectors are the two main approaches currently employed. Viral vectors are one of the major vehicles in gene therapy; however, the potent immunogenicity and the insertional mutagenesis is a potential issue for the patient. Non-viral vectors, such as polymeric nanocarriers, provide a safer and more efficient delivery of RNA-interfering molecules. The aim of this work is to employ PLGA core nanoparticles shell-coated with chitosan oleate as siRNA carriers. An siRNA targeted on HIV-1, directed against the viral Tat/Rev transcripts was employed as a model. The ionic interaction between the oligonucleotide's moieties, negatively charged, and the positive surface charges of the chitosan shell was exploited to associate siRNA and nanoparticles. Non-covalent bonds can protect siRNA from nuclease degradation and guarantee a good cell internalization and a fast release of the siRNA into the cytosolic portion, allowing its easy activation.