PCSK9 Research Articles

Cholesterol and Cholesterol-Lowering Medications in COVID-19—An Unresolved Matter

Infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cause coronavirus disease 2019 (COVID-19), a disease with very heterogeneous symptoms. Dyslipidaemia is prevalent in at least 20% of Europeans, and dyslipidaemia before SARS-CoV-2 infection increases the risk for severe COVID-19 and mortality by 139%. Many reports described reduced serum cholesterol levels in virus-infected patients, in particular in those with severe disease. The liver is the major organ for lipid homeostasis and hepatic dysfunction appears to occur in one in five patients infected with SARS-CoV-2. Thus, SARS-CoV-2 infection, COVID-19 disease severity and liver injury may be related to impaired cholesterol homeostasis. These observations prompted efforts to assess the therapeutic opportunities of cholesterol-lowering medications to reduce COVID-19 severity. The majority of studies implicate statins to have beneficial effects on disease severity and outcome in COVID-19. Proprotein convertase subtilisin/kexin type 9 (PCSK9) antibodies have also shown potential to protect against COVID-19. This review describes the relationship between systemic cholesterol levels, liver injury and COVID-19 disease severity. The potential effects of statins and PCSK9 in COVID-19 are summarised. Finally, the relationship between cholesterol and lung function, the first organ to be affected by SARS-CoV-2, is described.

Integrated bioinformatics analysis identifies PCSK9 as a prognosticator correlated with lipid metabolism in pancreatic adenocarcinoma

BackgroundPancreatic adenocarcinoma (PAAD) is the most frequent kind of pancreatic cancer (PC). Recent studies suggest that lipid metabolism facilitates tumorigenesis, disease progression, and resistance to therapy by promoting lipid synthesis, accumulation, and breakdown. Thus, exploring the lipid metabolism network could unveil novel therapeutic avenues for early detection, precision medicine, and prognostication in PAAD. This project intends to develop new lipid metabolism-related biomarkers for PAAD diagnosis and investigate the link between important genes and immune cell infiltration (ICI).MethodsTissue samples from 20 PAAD patients and 20 healthy controls were obtained. Analysis were focused on the datasets GSE71729 and GSE16515, which include samples of PAAD (n = 161) and those from healthy human tissue (n = 61), derived from the GEO database. Knockdown of PCSK9 on PC cells were conducted by si-RNA and sh-RNA. Migration and cell functional experiments were performed to assess the role of PCSK9 in cell multiplication. Furthermore, a xenograft mouse model was employed to confirm PCSK9's function in vivo.ResultsThe expression level of Proprotein convertase subtilisin/kexin type 9 (PCSK9) is significantly elevated in tissues affected by PAAD when compared to normal tissues. Survival analyses indicated that increased PCSK9 levels are inversely related to overall and disease-free survival (DFS). PCSK9’s functional annotation associated it with the cell cycle and metabolism, especially energy metabolism. Examination of ICI data determined that PCSK9 expression demonstrated an unambiguous association with the M0 macrophages, T follicular helper cells (Tfh), gamma delta T cells and activated DC, and an inverse relationship with Monocytes, CD8+ T cells, memory B cells, resting CD4+ memory T cells, activated NK cells and resting DC abundance. PCSK9 expression knockdown has the ability to impede PC cells’ migration and proliferation.ConclusionOur study identified PCSK9 as a critical gene in PAAD. Expression levels of PCSK9 varied between PAAD and normal samples. ROC analysis verified PCSK9's strong capacity to differentiate PC from normal samples. Importantly, PCSK9 expression was considerably elevated in PC cell lines and tissues. Furthermore, PCSK9 stimulates the migration and proliferation of tumor cells in vivo and vitro.

Prevalence of genetically diagnosed familial hypercholesterolemia in Vietnamese patients with premature acute myocardial infarction.

Familial hypercholesterolemia (FH) is a genetic disorder that results in elevated low-density lipoprotein cholesterol (LDL-C) levels, which manifest early in the first decades of life. It is a major cause of premature coronary artery disease worldwide, leading to significant public health challenges. The prevalence of genetically determined FH in patients with premature coronary artery disease remains underestimated, particularly in developing countries. This study aimed to assess the prevalence of genetically defined FH in Vietnamese patients with premature acute myocardial infarction (AMI) in the Vietnamese population. This cross-sectional study enrolled 218 consecutive patients diagnosed with premature AMI who underwent coronary angiography. The low-density lipoprotein receptor (LDLR), apolipoprotein B, and proprotein convertase subtilisin-kexin type 9 genes were analyzed by next-generation sequencing. FH was diagnosed according to Dutch Lipid Clinic Network criteria. Among the patients with premature AMI who underwent coronary angiography, the mean age was 46.9 ± 6.1 years, with a predominance of males (83.9%). The prevalence of potential FH diagnosed using Dutch Lipid Clinic Network criteria was 14.7% (definite FH, 6.0%; probable FH, 8.7%). Pathogenic or likely pathogenic variants in LDLR, apolipoprotein B, and proprotein convertase subtilisin-kexin type 9 were found in 9 of 218 patients (4.1%), all of which were causative mutations in LDLR. Patients with premature AMI and FH had significantly greater LDL-C levels (217.6 vs 125.7 mg/dL) and more severe coronary artery lesions, as assessed by the Gensini score (100.3 vs 60.5), than did those in the No FH group. The prevalence of genetically determined FH among Vietnamese patients with premature AMI is relatively high. Screening and diagnosis of hereditary conditions in patients with premature AMI are essential to improve early detection and management and reduce the burden of coronary artery disease in this population.

Causal effects of lipid-lowering drugs on skin diseases: a two-sample Mendelian randomization study.

Although previous studies have indicated an association between low-density lipoprotein (LDL) and skin diseases, their causal effects remain inconclusive. This study aimed to assess the causal relationship between genetically proxied lipid-lowering drugs and skin cancers and psoriasis. Two-sample Mendelian randomization (MR) analysis was performed using single-nucleotide polymorphisms (SNPs) from genome-wide association studies (GWAS). The inverse-variance weighted (IVW) method was used to determine causal relationships. The "leave-one-out" sensitivity test, Cochran's Q-statistic and MR-Egger intercept were used to assess heterogeneity and horizontal pleiotropy. We identified 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) and proprotein convertase subtilisin-kexin type 9 (PCSK9) as genetically proxied lipid-lowering drugs. Genetically proxied inhibition of HMGCR (stains) was causally associated with reduced risk of nonmelanoma skin cancer (OR 0.982, 95% CI 0.967-0.997, p = 0.016 by weighted median; OR 0.977, 95% CI 0.966-0.989, p < 0.001 by IVW) and psoriasis (OR 0.585, 95% CI 0.378-0.905, p = 0.016 by IVW), while PCSK9 inhibition (alirocumab) was causally associated with reduced risk of psoriasis (OR 0.560, 95% CI 0.413-0.761 by weighted median; OR 0.564, 95% CI 0.447-0.712 by IVW; p < 0.001) in the ieu-b-5089 dataset. Similar results were observed in the ieu-b-110 dataset for HMGCR and PCSK9. Sensitivity analysis revealed no evidence of heterogeneity or horizontal pleiotropy. This study revealed the existing HMGCR inhibitors (stains) might be protective for reducing nonmelanoma skin cancer risk, and HMGCR inhibitors (stains) and PCSK9 inhibitor (alirocumab) might be promising for reducing psoriasis risk in the European population.

The efficacy and safety of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors combined with statins in patients with hypercholesterolemia: a network meta-analysis.

In recent years, the position of PCSK9 inhibitors as adjuvant therapy to statins in guidelines has further improved. However, there remained a dearth of direct comparative studies among different PCSK9 inhibitors. Therefore, this study aimed to conduct a network meta-analysis to evaluate the efficacy and safety of different PCSK9 inhibitors combined with statins. A comprehensive literature search was conducted from the study's inception to 12 November 2023, encompassing multiple online databases including PubMed, Embase, Cochrane Central, Web of Science, and ClinicalTrials.gov to obtain relevant randomized controlled trials. Frequentist network meta-analysis was employed to compare the efficacy and safety of different PCSK9 inhibitors. The efficacy endpoints were low-density lipoprotein cholesterol (LDL-C), apolipoprotein B (ApoB), and lipoprotein (a) (Lp(a)). The safety endpoints were any adverse events (AE), severe adverse events (SAE), AE leading to treatment discontinuation, and injection-site reaction. Compared with placebo and ezetimibe, all PCSK9 inhibitors demonstrated significant reductions in LDL-C levels. Notably, evolocumab exhibited the most pronounced effect with a treatment difference of -63.67% (-68.47% to -58.87%) compared with placebo. Regarding dosage selection for evolocumab, the regimen of 140 mg Q2W (-69.13%, -74.55% to -63.72%) was superior to 420 mg QM (-61.51%, -65.97% to -57.05%). Based on rankings and P-scores analysis, tafolecimab 150 mg Q2W demonstrated superior efficacy in reducing ApoB levels (-61.70%, -84.38% to -39.02%) and Lp(a) levels (-43%, 30%, -68%, 81% to -17%, 79%). Furthermore, the safety profile of PCSK9 inhibitors was favorable with no increase in the incidence of AE, SAE, or AE leading to treatment discontinuation; however, alirocumab, inclisiran, and tafolecimab may potentially entail a potential risk associated with injection-site reactions. Compared with placebo and ezetimibe, PCSK9 inhibitors can significantly reduce LDL-C, ApoB, and Lp(a) when combined with statins to treat hypercholesterolemia. Furthermore, PCSK9 inhibitors and ezetimibe exhibit similar safety profiles. [PROSPERO], identifier [CRD42023490506].

Inclisiran: A Systematic Review Exploring the Revolutionary Approach of Twice-Yearly Dosing Regimen in the Treatment of Hypercholesterolemia.

The global burden of hyperlipidemia is on the rise, along with an increase in associated cardiovascular complications. Since most of the patients affected by hyperlipidemia are elderly individuals with multiple comorbidities, the introduction of even a single additional drug for asymptomatic conditions such as hyperlipidemia can drastically reduce treatment compliance due to their long medication history. Hence, researchers are trying to come up with a drug with a long duration of action requiring less frequent dosing without compromising compliance and improving the outcome. This led to the discovery of inclisiran, a "wonder drug" that utilizes small interference RNA and requires only twice-yearly administration to maintain patients' lipid levels at optimal levels. We conducted a systematic review by following standardized guidelines on the long-term efficacy and safety of the new drug, inclisiran, in the treatment of hypercholesterolemia. We conducted an advanced search on PubMed using the MeSH strategy and then employed appropriate keywords to search other major databases, such as PubMed Central and Medline, using various inclusion and exclusion criteria, which yielded 94 articles from various databases.We narrowed down the search to 10 randomized controlled trials (ORION trials) after removing duplicates and screening for irrelevant titles for inclusion in the study. The ORION trials on inclisiran evaluated the drug's impact on various parameters, such as low-density lipoprotein-cholesterol (LDL-C), proprotein convertase subtilisin/kexin type 9 (PCSK9), high-density lipoprotein (non-HDL), apolipoprotein B (apoB), and so on, whileconsidering the safety aspects of the drug. All the trials indicate greater efficacy of inclisiran and long-term maintenance of the results achieved when compared to a placebo and showed a long dosing interval, thereby increasing treatment compliance. Additionally, as the drug's dose increased, we observed greater reductions in the mentioned parameters without a significant increase in the incidence of adverse events. According to the review's data analysis, inclisiran, with its greater efficacy, has the potential to replace conventional pharmacological therapy in the near future, with the best results achieved when combined with lifestyle modifications. However, a long-term assessment of the drug's efficacy and safety is required before implementing it in clinical practice to identify any potential safety concerns, particularly related to the administration of higher dosage over a longer period.

Functional and morphological improvement of significant non-culprit coronary artery stenosis by LDL-C reduction with a PCSK9 antibody: Rationale and design of the randomized FITTER trial

Non-culprit coronary artery lesions are commonly present in patients presenting with an acute coronary syndrome (ACS). Additional stenting of non-culprit lesions in addition to the culprit lesion intends to prevent secondary events caused by these lesions. At the same time, multiple trials have demonstrated the potential of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors in reducing plaque size and changing plaque composition of non-culprit lesions. Whether intensive low-density lipoprotein cholesterol (LDL-C) reduction with PCSK9 inhibitor evolocumab improves non-culprit vessel hemodynamics, reduces the risk of plaque rupture of important non-culprit lesions, and might obviate the need for additional stenting has not been investigated. The “Functional Improvement of non‐infarcT related coronary artery stenosis by Extensive LDL‐C Reduction with a PCSK9 Antibody” (FITTER) trial is a multi-center, randomized, double-blind, placebo-controlled clinical trial for patients presenting with ACS and multivessel disease (MVD). After treatment of the culprit lesion, fractional flow reserve (FFR) is performed in non-culprit vessels amenable for percutaneous coronary intervention (PCI). Coronary intervention in patients with hemodynamically important non-critical lesions (FFR: 0.67–0.85) is staged after baseline imaging using near-infrared spectroscopy (NIRS) and intravascular ultrasound (IVUS). Eligible patients are randomized and treated for 12 weeks with either evolocumab or placebo, in addition to high-intensity statin therapy. Follow-up angiography with repeat FFR and IVUS-NIRS is scheduled at 12 weeks. Staged PCI is performed at the operator's discretion.The FITTER trial is the first study to evaluate the effect of maximal LDL-C reduction by the PCSK9 inhibitor evolocumab on invasively measured FFR, plaque size, and plaque composition in hemodynamically important non-culprit lesions, during a treatment period of just 12 weeks after an ACS. Currently, all patients have been included (August 2023) and data analysis is ongoing. Trial registration numberclinicaltrials.gov NCT04141579.

Trends and Prospects of Low-Density Lipoprotein Cholesterol in Stroke: A Bibliometric Analysis.

Management of low-density lipoprotein cholesterol (LDL-C) in stroke is a crucial component of cardiovascular disease care. Recent years have seen substantial progress in understanding and managing LDL-C in the context of stroke. This study utilized bibliometric methods to analyze and synthesize trends in this area over the past decade, incorporating 2,841 publications from the Web of Science database. The analyses included trend topic analysis, co-authorship analysis, and co-citation analysis. The findings indicate that research had predominantly concentrated on epidemiological studies related to pharmacological management strategies. Future research is expected to continue exploring lipid-lowering therapies, including both established treatments like statins and newer drugs such as proprotein convertase subtilisin-kexin type 9 inhibitors. Assessing residual cholesterol and employing Mendelian randomization techniques may become potential research hotspots. The New England Journal of Medicine is the most globally influential journal, while Circulation holds the most influence within the field, and Atherosclerosis ranks as the most prolific. International collaboration in this research area was strong between the USA and England, followed by the USA and China. However, collaboration between productive institutions in the USA and China remains limited, highlighting the need to strengthen partnerships between these institutions to further advance the field.

Novel insights into the association between genetically proxied inhibition of proprotein convertase subtilisin/kexin type 9 and risk of sarcopenia.

The effects of lipid-lowering drugs [including statins, ezetimibe, and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors] on hyperlipidaemia have been established. Some may have treatment effects beyond their reported properties, offering potential opportunities for drug repurposing. Epidemiological studies have reported conflicting findings on the relationship between lipid-lowering medication use and sarcopenia risk. We performed a two-sample Mendelian randomization (MR) study to investigate the causal association between the use of genetically proxied lipid-lowering drugs (including statins, ezetimibe, and PCSK9 inhibitors, which use low-density lipoprotein as a biomarker), and sarcopenia risk. The inverse-variance weighting method was used with pleiotropy-robust methods (MR-Egger regression and weighted median) and colocalization as sensitivity analyses. According to the positive control analysis, genetically proxied inhibition in lipid-lowering drug targets was associated with a lower risk of coronary heart disease [PCSK9 (OR, 0.67; 95% CI, 0.61 to 0.72; P=7.7E-21); 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR; OR, 0.68; 95% CI, 0.57 to 0.82; P=4.6E-05), and Niemann-Pick C1-like 1 (NPC1L1; OR, 0.53; 95% CI, 0.40 to 0.69; P=3.3E-06)], consistent with drug mechanistic actions and previous trial evidence. Genetically proxied inhibition of PCSK9 (beta, -0.040; 95% CI, -0.068 to -0.012; P=0.005) and circulating PCSK9 levels (beta, -0.019; 95% CI, -0.033 to -0.005; P=0.006) were associated with reduced appendicular lean mass (ALM) with concordant estimates in terms of direction and magnitude. Validation analyses using a second instrument for PCSK9 yielded consistent results in terms of direction and magnitude [(PCSK9 to ALM; beta, -0.052; 95% CI, -0.074 to -0.032; P=7.1E-7); (PCSK9 protein to ALM; beta, -0.060; 95% CI, -0.106 to -0.014; P=0.010)]. Genetically proxied inhibition of PCSK9 gene expression in the liver may be associated with reduced ALM (beta, -0.013; 95% CI, -0.035 to 0.009; P=0.25), consistent with the results of PCSK9 drug-target and PCSK9 protein MR analyses, but the magnitude was less precise. No robust association was found between HMGCR inhibition (beta, 0.048; 95% CI, -0.015 to 0.110; P=0.14) or NPC1L1 (beta, 0.035; 95% CI, -0.074 to 0.144; P=0.53) inhibition and ALM, and validation and sensitivity MR analyses showed consistent estimates. This MR study suggested that PCSK9 is involved in sarcopenia pathogenesis and that its inhibition is associated with reduced ALM. These findings potentially pave the way for future studies that may allow personalized selection of lipid-lowering drugs for those at risk of sarcopenia.

Use and effectiveness of PCSK-9 inhibitors in heart diseases: A review.

Proprotein Convertase Subtilisin/Kexin type-9 (PCSK-9) inhibitors have recently used in the management of different cardiac complications. Several clinical trials demonstrated their effectiveness in patients with hypercholesterolemia. However, the effectiveness of these medications in patients with heart diseases is still controversial. To review and summarize the clinical trials pertaining to the use and effectiveness of PCSK-9 inhibitors in heart diseases and to discuss the pharmacotherapy of these agents. A review was conducted of all clinical trials with PCSK-9 inhibitors for heart diseases registered at ClinicalTrials.gov since inception up to and including January 19th, 2024. These trials were retrieved. Data from these trials were extracted manually, categorized and analyzed. The number of identified clinical trials was 25,371. After screening and excluding irrelevant studies, 12 studies met the search criteria. The majority of these studies were conducted in the US. The total number of patients in these studies was 27,700. Alirocumab and Evolocumab were the most frequently used PCSK-9 inhibitors. This review identified only a few clinical trials on PCSK-9 inhibitors in heart disease patients. Therefore, it is recommended to conduct more randomized controlled clinical trials on PCSK-9 inhibitors in this patient population.

Dyslipidemias in multiple sclerosis

PurposeTo investigate the frequency of dyslipidemia phenotypes in multiple sclerosis and to assess the associations with lipoprotein particle size distributions. MethodsThis cross-sectional study included 203 healthy controls (HC), 221 relapsing-remitting MS (RRMS), and 126 progressive MS (PMS). A lipid profile with total cholesterol, high-density lipoprotein cholesterol (HDL-C), triglycerides, and apolipoprotein B levels were measured. Low density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol, large buoyant LDL-C and small dense LDL-C were calculated using the Sampson-NIH equations method. Dyslipidemia phenotypes were categorized by their nonHDL-C and triglyceride values. The diameters and concentrations of triglyceride-rich lipoprotein particles (TRLP), LDL particles (LDLP), and HDL particles (HDLP) were measured with proton NMR lipoprotein profiling. Serum proprotein convertase subtilisin/kexin type 9 (PCSK9) levels were obtained using immunoassay. ResultsThe frequencies of normolipidemia, and various dyslipidemia phenotypes were similar in HC, RRMS, and PMS. The size of the TRLP, very large TRLP, large TRLP, and small LDLP concentrations had a decreasing pattern of HC>RR>PMS. The lowest tertile of EDSS was associated with higher concentrations of HDLP and small HDLP in PMS. PCSK9 was associated with concentration of HDL particles, primarily via its effects on the concentration of small HDL particles. ConclusionsThere were no differences in the frequency of dyslipidemias in MS compared to healthy controls. Higher HDLP concentrations are associated with lower disability in PMS.

PCSK9 Inhibitors and Anthracyclines: The Future of Cardioprotection in Cardio-Oncology.

The field of cardio-oncology is an expanding frontier within cardiovascular medicine, and the need for evidence-based guidelines is apparent. One of the emerging focuses within cardio-oncology is the concomitant use of medications for cardioprotection in the setting of chemotherapy regimens that have known cardiovascular toxicity. While clinical trials focusing on cardioprotection during chemotherapy are sparse, an inaugural trial exploring the prophylactic potential of Sodium-Glucose Cotransporter-2 inhibitors (SGLT2is) for anthracycline (ANT)-induced cardiotoxicity has recently commenced. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, though less studied in this oncology demographic, have exhibited promise in preclinical studies for conferring cardiac protection during non-ischemic toxic insults. While primarily used to reduce low-density lipoprotein, PCSK9 inhibitors exhibit pleiotropic effects, including the attenuation of inflammation, reactive oxygen species, and endothelial dysfunction. In ANT-induced cardiotoxicity, these same processes are accelerated, resulting in premature termination of treatment, chronic cardiovascular sequelae, heart failure, and/or death. This review serves a dual purpose: firstly, to provide a concise overview of the mechanisms implicated in ANT-induced cardiotoxicity, and, finally, to summarize the existing preclinical data supporting the theoretical possibility of the cardioprotective effects of PCSK9 inhibition in ANT-induced cardiotoxicity.

The German Lipoprotein Apheresis Registry-Summary of the eleventh annual report

BackgroundIn 2012, the German Lipoprotein Apheresis Registry (GLAR) was launched. Real-world data on lipoprotein apheresis (LA) treatment are now available for a time period of 11 years. All patients received the maximally tolerated lipid-lowering therapy, which included statins, ezetimibe, bempedoic acid, and either proprotein convertase subtilisin/kexin type 9 (PCSK9) antibodies or antisense therapy. Methods and ResultsDuring the time period from 2012 to 2022, 92 German apheresis centers collected retrospective and prospective observational data of a total of 2,301 patients undergoing regular lipoprotein apheresis (LA) treatment of hypercholesterolemia or/and Lp(a)-hyperlipoproteinemia suffering from progressive atherosclerotic cardiovascular disease (ASCVD), with complete data sets of 1.125 patients, who were the subject of this analysis. More than 61,500 LA sessions are documented in the database. In 2022, all patients treated with LA demonstrated a significant immediate median reduction rate of LDL-C (68.8 %) and Lp(a) (72.9 %). Patient data were analyzed for the incidence rate of major coronary events (MACE) 1 and 2 years before the beginning of LA treatment (y-2 and y-1) and prospectively up to eleven years on LA treatment (y+1 to y+11). During the first two years of LA treatment (y+1 and y+2), a MACE reduction of 73 % was observed and continued to be low during y+3 to y+11, when all LA patients were analyzed. LA patients with only increased Lp(a) levels (Lp(a) ≥ 60 mg/dl (≥120 nmol/l) and an LDL-C < 100 mg/dl (<2.6 mmol/l)) had a higher MACE reduction (85 %; n = 443) in the first two years of LA treatment compared to LA patients with only increased LDL-C-levels (LDL-C ≥ 100 mg/dl (≥2.6 mmol/l); Lp(a) < 60 mg/dl (<120 nmol/l)) (53 %; n = 171). Adverse events of LA remained low (about 5 %) over the eleven years and mainly represented puncture problems (1.0 %). No side effects resulted in termination of LA therapy. ConclusionsThe current analysis of GLAR data indicates that regular LA leads to very low incidence rates of cardiovascular events in patients with high LDL-C and/or high Lp(a) levels, progressive ASCVD, and maximally tolerated lipid-lowering medication, including proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition. Additionally, LA was safe with a low rate of adverse effects over an 11-year period. The number of enrolled patients and the duration of observation establish GLAR as the largest LA registry worldwide.

Transforming hypercholesterolemia management: Spotlight on PCSK9 peptide vaccines

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a therapeutic target for dyslipidemia and atherosclerotic cardiovascular disease (ASCVD). Two recent studies published by Fang etal.1 and Zhang etal.2 in Cell Reports Medicine and Cell Reports, respectively, show the efficacy of peptide vaccines in eliciting an antibody response against PCSK9 and reducing plasma cholesterol levels.

Ferritin-based disruptor nanoparticles: A novel strategy to enhance LDL cholesterol clearance via multivalent inhibition of PCSK9-LDL receptor interaction.

Hypercholesterolemia, characterized by elevated low-density lipoprotein (LDL) cholesterol levels, is a significant risk factor for cardiovascular disease. Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a crucial role in cholesterol metabolism by regulating LDL receptor degradation, making it a therapeutic target for mitigating hypercholesterolemia-associated risks. In this context, we aimed to engineer human H ferritin as a scaffold to present 24 copies of a PCSK9-targeting domain. The rationale behind this protein nanoparticle design was to disrupt the PCSK9-LDL receptor interaction, thereby attenuating the PCSK9-mediated impairment of LDL cholesterol clearance. The N-terminal sequence of human H ferritin was engineered to incorporate a 13-amino acid linear peptide (Pep2-8), which was previously identified as the smallest PCSK9 inhibitor. Exploiting the quaternary structure of ferritin, engineered nanoparticles were designed to display 24 copies of the targeting peptide on their surface, enabling a multivalent binding effect. Extensive biochemical characterization confirmed precise control over nanoparticle size and morphology, alongside robust PCSK9-binding affinity (KD in the high picomolar range). Subsequent efficacy assessments employing the HepG2 liver cell line demonstrated the ability of engineered ferritin's ability to disrupt PCSK9-LDL receptor interaction, thereby promoting LDL receptor recycling on cell surfaces and consequently enhancing LDL uptake. Our findings highlight the potential of ferritin-based platforms as versatile tools for targeting PCSK9 in the management of hypercholesterolemia. This study not only contributes to the advancement of ferritin-based therapeutics but also offers valuable insights into novel strategies for treating cardiovascular diseases.

Investigating Ethanolic Extract from Acehnese Lime (Citrus aurantifolia) Peel as Potential Anti-Hypercholesterolemia Agent

Lime peels are rich in flavonoids, alkaloids, phenols, saponins, and tannins, exhibiting antibacterial, antioxidant, anti-inflammatory, anti-hypertensive, and anti-hypercholesterolemia properties. However, the specific active constituents of Acehnese lime peels and their impact on anti-hypercholesterolemia effects remain undisclosed. This present investigation aims to identify the active compounds in the ethanolic extract of locally obtained Acehnese lime (Citrus aurantifolia (Christm.) Swingle) peels and assess their potential as inhibitors of Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) and 3-hydroxy-3-methylglutaryl-coenzyme-A (HMG Co-A) reductase using in-silico approach. The composition of the ethanolic extract Acehnese lime peel was determined through phytochemical analysis, 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, gas chromatography-mass spectrometry (GC-MS) analysis, and predictions of biological activity, while the biological activities of their compounds were evaluated through molecular docking. Phytochemicals revealed the presence of phenolics, flavonoids, tannins, saponins, and terpenoids in the ethanolic extract of local Aceh lime peel. The total phenolic and flavonoid contents were 29.992 ± 0.274 mg gallic acid equivalents (GAE)/g extract and 5.983 ± 0.017 mg quercetin equivalents (QE)/g extract, respectively. The anti-oxidant activity was notably strong with an IC50 value of 49.51 ppm. GC-MS analysis identified 6-methoxychroman-2-one (27.64%) as the primary component in ethanolic extract Acehnese lime peel, along with neric acid (C13H22O2) known as a regulator of lipid metabolism (Pa: 0.941). In-silicoinvestigations indicated that pterin-6-carboxylic acid (-7.8 kcal/mol) exhibited a higher binding free energy for the PCSK9 receptor compared to simvastatin (-7.6 kcal/mol), whereas the active compound (R)-9-(2,3-dihydroxy-3-methylbutoxy)-4- exhibited the highest binding capacity for HMG Co-A reductase (-6.9 kcal/mol) compared to other compounds. These findings suggest that the ethanolic extract of Acehnese lime peels could serve as an effective inhibitor of PCSK9 and HMG Co-A reductase, highlighting its potential as a novel anti-hypercholesterolemia agent. Doi: 10.28991/HEF-2024-05-03-04 Full Text: PDF

O75 INHIBITION OF PCSK9/NFAT AMELIORATES CARDIAC DYSMETABOLISM AND FIBROSIS IN EXPERIMENTAL RAT MODEL OF PCOS BY REDUCING ATHEROGENIC LIPID AND IMPROVING INSULIN SENSITIVITY

Background: Polycystic ovarian syndrome (PCOS) remains an independent risk factor of cardiovascular disease (CVD), particularly in women of child-bearing age, and contributes to global increase in the prevalence/incidence of cardiovascular mortality and morbidity in women. Proprotein convertase subtilisin/kexin type 9 (PCSK9) has emerged as a promising therapeutic target to reduce residual CVD risk. Similarly, Nuclear factor of activated T cells (NFAT) is a transcription factor that is implicated in cardiac fibrosis. However, the role of PCSK9/NFAT in PCOS-associated cardiometabolic syndrome is not clear. Short chain fatty acids (SCFAs) play a multifaceted regulatory role in metabolic health. The present study therefore investigated the role of PCSK9/NFAT in cardiometabolic syndrome associated with experimental PCOS, and the therapeutic potential of SCFAs, especially butyrate. Material and Methods: Eight-week-old female Wistar rats were allotted into four groups (n=5). Polycystic ovarian syndrome was induced by administering letrozole (1 mg/kg p.o.) once daily for 21 days, thereafter the animals were treated with 200 mg/kg (oral gavage) of sodium butyrate for six weeks. Gene expression, biochemical parameters and cardiac/ovarian morphology were evaluated with appropriate methods. Results: Rats with PCOS showed androgen excess, multiple ovarian cysts and reduced insulin sensitivity. The rats in addition displayed atherogenic dyslipidemia (triglyceride/HDLc, TC/HDLc and LDLc), hypercorticosteronemia and elevated cardiac triglyceride, inflammatory biomarkers (NF-kappaB and TNF-alpha), caspase-6, 4-hydroxynonenal, inflammasome (NLRP3), fibrosis and depleted antioxidant defense (NrF2 and glutathione) as well as increased expression of PCSK9 and NFAT when compared to the control rats. Nevertheless, these systemic and morphological alterations were ameliorated following treatment with sodium butyrate. Conclusion: The present results collectively demonstrate cardiac dysmetabolism, inflammation, fibrosis as well as apoptosis in experimental PCOS rat model, which are driven by elevated expression of PCSK9/NFAT. The results further suggest that SCFAs, butyrate alleviates cardiometabolic syndrome and its attendant cardiomorbidity by suppression of PCSK9/NFAT. The present data provide a preclinical insight to prevention and management of CVD in PCOS individuals.

Efficacy of Traditional Anti-lipidemic Drugs in Lowering Lipoprotein(a) Levels: A Systematic Review.

Lipoprotein(a), or Lp(a), was identified in the early 1960.Its role as an independent risk factor for atherosclerotic cardiovascular disease (ASCVD) became widely recognized by the late 20th century, regardless of other traditional risk markers such as low-density lipoproteins and high-density lipoproteins. This study aimed to systematically review available literature and compare the efficacy of different lipid-lowering drugs, both approved for clinical use and currently undergoing trials, in lowering Lp(a) levels. A comprehensive search of medical databases including PubMed, PubMed Central (PMC), Medline, ScienceDirect, Cochrane Library, and Google Scholar was conducted to identify relevant studies. A total of 29 research papers met the inclusion criteria, focusing on the impact of various lipid-lowering drugs on Lp(a) concentration in patients with significantly elevated baseline Lp(a) levels. Plasma Lp(a) levels exceeding 30 mg/dL are associated with a higher risk of ASCVD, including myocardial infarction, stroke, aortic valve stenosis, heart failure, peripheral arterial disease, and increased all-cause mortality. Most commonly used lipid-lowering agents, such as statins, fibrates, ezetimibe, and nutraceuticals like coenzyme Q10 (CoQ10), showed no significant effect on Lp(a) plasma levels. However, Lp(a) apheresis and proprotein convertase subtilisin/kexin type 9 (PCSK-9) inhibitors were found to effectively reduce plasma Lp(a) concentrations. Emerging therapies targeting apolipoprotein(a) RNA, including anti-sense oligonucleotides (ASO) and small interfering RNA (siRNA), significantly reduced Lp(a) levels in Phase 2 trials. While several lipid-lowering agents have minimal impact on Lp(a) levels, therapies like Lp(a) apheresis, PCSK-9 inhibitors, and novel RNA-targeting drugs show promise in effectively reducing Lp(a) concentrations. However, whether these reductions translate into decreased cardiovascular events remains to be determined.

LIpid Response to Statins ± Ezetimibe In Mumbai (LIRIM): A Cross-sectional Observational Study.

India has the highest burden of cardiovascular disease (CVD) among developing nations. Data from international studies show significant underimplementation of recommended aggressive lipid-lowering strategies for achieving low-density lipoprotein cholesterol (LDL-C) goals, especially after percutaneous coronary intervention (PCI), a pattern also observed in India. Moreover, ethnic variation in response to statin therapy has prompted clinicians to adopt lower doses of statin therapy in Asians to achieve comparable LDL-C lowering. To document the dose of statin ± ezetimibe required to achieve the European Society of Cardiology (ESC) goals of LDL-C <55 mg/dL in Indian patients with established atherosclerotic cardiovascular disease (ASCVD). This retrospective single-center, cross-sectional, observational, all-comers study in Mumbai evaluated the dose of atorvastatin (A)/rosuvastatin (R) ± ezetimibe (E) treatment at which patients with established ASCVD (n = 542), irrespective of their baseline level, achieved LDL-C goals (<55 mg/dL). Those with LDL-C levels >55 mg/dL on current therapy were switched to R 40 mg ± E 10 mg daily. The final data set (n = 340) included those who achieved LDL-C goals at the initial visit and those at follow-up. The primary and secondary outcomes assessed the impact of R 40 mg ± E 10 mg (R40 ± E10) on LDL-C (<55 mg/dL) and non-high-density lipoprotein cholesterol [non-HDL-C (<85 mg/dL)] goal achievement, respectively. At the end of follow-up, LDL-C <55 mg/dL was observed in 42.16% of patients (n = 113) with R40 and in another 43.28% (n = 116) with R40 + E10. A few patients (n = 39; 14.6%) achieved this goal with other dosages. Similarly, non-HDL-C <85 mg/dL was observed in 39.3% of patients (n = 107) with R40 and in another 47.4% of patients (n = 129) with R40 + E10. Overall, around 20% of patients were unable to achieve their LDL-C and non-HDL-C goals despite being on high-intensity statin ± E therapy. In the first report of its kind in India, this study showed that suboptimal LDL-C goal achievement occurred in around 20% of high-risk ASCVD patients on dual therapy. This indicates that clinicians should consider the addition of other therapies [e.g., bempedoic acid, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, and inclisiran] to mitigate the residual risk. Several more trials are needed to determine the most suitable treatment regimen for this population.

Statins, but not proprotein convertase subtilisin-kexin type 9 inhibitors, lower chemerin in hypercholesterolemia via low-density lipoprotein receptor upregulation.

Hypercholesterolemia is characterized by elevated low-density lipoprotein (LDL)-cholesterol levels and an increased risk of cardiovascular disease. The adipokine chemerin is an additional risk factor. Here we investigated whether cholesterol-lowering with statins or proprotein convertase subtilisin-kexin type 9 inhibitors (PCSK9i) affects chemerin. Both statins and PCKS9i lowered plasma LDL-cholesterol, triglycerides and total cholesterol in hypercholesterolemic patients, and increased high-density lipoprotein (HDL)-cholesterol. Yet, only statins additionally reduced chemerin and high-sensitivity C-reactive protein (hsCRP). Applying PCSK9i on top of statins did not further reduce chemerin. Around 20% of chemerin occurred in the HDL2/HDL3 fractions, while>75% was free. Statins lowered both HDL-bound and free chemerin. Pull-down assays revealed that chemerin binds to the HDL-component Apolipoprotein A-I (ApoA-I). The statins, but not PCSK9i, diminished chemerin secretion from HepG2 cells by upregulating LDL receptor mRNA. Furthermore, chemerin inhibited HDL-mediated cholesterol efflux via its chemerin chemokine-like receptor 1 in differentiated macrophages. In conclusion, statins, but not PCSK9i, lower circulating chemerin by directly affecting its release from hepatocytes. Chemerin binds to ApoA-I and inhibits HDL-mediated cholesterol efflux. Statins prevent this by lowering HDL-bound chemerin. Combined with their anti-inflammatory effect evidenced by hsCRP suppression, this represents a novel cardiovascular protective function of statins that distinguishes them from PCSK9i.