Lipid Lowering Therapy and Circulating PCSK9 Concentration

Chemical constituents from the roots of Cynanchum wilfordii with PCSK9 secretion inhibitory activities

From the Cynanchum wilfordii roots, 32 compounds, including 5 previously undescribed (1, 4-6, 12) and 27 known (2, 3, 7-11, 13-32) compounds, were isolated, and their structures were elucidated using NMR spectroscopic data and MS data aided by ECD calculations or the modified Mosher's reaction. All isolates were tested for their inhibitory effects on proprotein convertase subtilisin/kexin type 9 (PCSK9) secretion. Among the isolates, compound 4, a methyl cholesterol analog, exhibited the most potent effect in reducing PCSK9 secretion, along with PCSK9 downregulation at the mRNA and protein levels via FOXO1/3 upregulation. Moreover, compound 4 attenuated statin-induced PCSK9 expression and enhanced the uptake of DiI-LDL low-density lipoprotein. Thus, compound 4 is suggested to be a potential candidate for controlling cholesterol levels.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) and clinical outcomes in dialysis patients

BACKGROUND

Proprotein convertase subtilisin/kexin type 9 (PCSK9), a factor accelerating the degradation of LDL receptors, was associated with a gender-dependent risk for cardiovascular (CV) events in the general population and with all-cause and CV mortality in two relatively small studies in black Africans and South Korean haemodialysis patients. The effect modification by gender was untested in these studies.

METHODS

The study enrolled 1188 dialysis patients from the Prospective Registry of The Working Group of Epidemiology of Dialysis Region Calabria (PROGREDIRE) cohort. PCSK9 was measured by colorimetric enzyme-linked immunosorbent assay. The primary outcomes were all-cause and CV mortality. Statistical analysis included Cox regression analysis and effect modification analysis.

RESULTS

During a median 2.9-year follow-up, out of 494 deaths, 278 were CV-related. In unadjusted analyses, PCSK9 levels correlated with increased all-cause (HRfor1ln unit increase: 1.23, 95% CI 1.06-1.43, p =.008) and CV mortality (HRfor1ln unit increase: 1.26, 95% CI 1.03-1.54, p =.03). After multivariate adjustment, these associations were no longer significant (all-cause mortality, HRfor 1 ln unit increase: 1.16, 95% CI .99-1.36, p =.07; CV mortality, HRfor1ln unit increase: 1.18, 95% CI .95-1.46, p =.14). However, in fully adjusted interaction analyses, a doubling in the risk of this outcome in women was registered (Women, HRfor1ln unit increase: 1.88, 95% CI 1.27-2.78, p =.002; Men, HRfor1ln unit increase: 1.07, 95% CI .83-1.38, p =.61; p for effect modification: .02).

CONCLUSIONS

PCSK9 levels are unrelated to all-cause mortality in haemodialysis patients but, like in studies of the general population, independently of other risk factors, entail a doubling in the risk of CV events in women in this population.

Low-density lipoprotein cholesterol response to statins according to comorbidities and co-medications: A population-based study

BACKGROUND

The response of low-density lipoprotein cholesterol (LDL-C) to statin therapy is variable, and may be affected by the presence of co-morbid conditions or the use of concomitant medications. Systematic variation in the response to statins based on these factors could affect the selection of the statin treatment regimen in population subgroups. We investigated whether common comorbidities and co-medications had clinically important effects on statin responses in individual patients.

METHODS

This register-based cohort study included 89,006 simvastatin or atorvastatin initiators with measurements of pre-statin and on-statin LDL-C levels, in Denmark, 2008-2018. We defined statin response as the percentage reduction in LDL-C, and used linear regression to estimate percentage reduction differences (PRD) according to 175 chronic comorbidities and 99 co-medications. We evaluated both the statistical significance (P-values corrected for multiple testing) and the clinical importance (PRD of 5 percentage points or more) of the observed associations.

RESULTS

Concomitant use of oral blood-glucose lowering drugs, which included metformin in 96% of treated individuals, was associated with a greater response to statin therapy that was both statistically significant and clinically important, with a PRD of 5.18 (95% confidence interval: 4.79 to 5.57). No other comorbidity or co-medication reached the prespecified thresholds for a significant, clinically important effect on statin response. Overall, comorbidities and co-medications had little effect on statin response, and altogether explained only 1.7% of the total observed population variance.

CONCLUSION

Most of the studied comorbidities and co-medications did not have a clinically important effect on statin response, suggesting no need to modify treatment regimens. However, use of metformin was associated with a significantly enhanced LDL-C response to statins, suggesting that lower statin doses may be effective in patients taking metformin.

Proprotein Convertase Subtilisin/Kexin Type 9 Induction in COVID-19 Is Poorly Associated with Disease Severity and Cholesterol Levels

SARS-CoV-2 infection was shown to induce proprotein convertase subtilisin/kexin type 9 (PCSK9) plasma levels in sepsis. Here, we investigate the association between serum PCSK9 levels and disease severity. PCSK9 was measured in serum of 55 controls, 40 patients with moderate and 60 patients with severe COVID-19 disease. Serum PCSK9 was elevated in moderate COVID-19 compared to controls and further increased in severe cases. PCSK9 levels were not associated with C-reactive protein, bacterial superinfections, interventions, or survival in patients with severe COVID-19. PCSK9 regulates circulating cholesterol levels, and 15 cholesteryl ester (CE) species and free cholesterol (FC) were quantified by direct flow injection analysis using a high-resolution hybrid quadrupole-Orbitrap mass spectrometer. Most CE species with shorter fatty acid chains were decreased in severe compared to moderate COVID-19, and none of the CE species were correlated with PCSK9 in patients with severe COVID-19. Levels of all CE species negatively correlated with C-reactive protein in severe COVID-19 patients. Notably, FC was induced in severe compared to moderate COVID-19. The FC/CE ratio correlated positively with inflammatory markers and was associated with non-survival. The current study suggests that the imbalance between CE and FC levels is associated with disease severity and mortality in patients with COVID-19.

Effectiveness and safety of injectable PCSK9 inhibitors in dyslipidaemias' treatment and cardiovascular disease prevention: An overview of 86 systematic reviews and a network metaanalysis

OBJECTIVE

Multiple systematic reviews (SR) have been performed on the effects of proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i), often providing conflicting findings. This overview and network meta-analysis (NMA) aimed to summarize SR findings on the efficacy and safety of PCSK9i and provide an updated NMA.

MATERIALS AND METHODS

MEDLINE (Pubmed), Scopus, Cochrane, Epistemonikos and Google Scholar were searched from inception to September 21, 2023 for SRs of randomized controlled trials (RCTs) and from January 1, 2020 to September 21, 2023 for additional RCTs. Double-independent study selection, data extraction and quality assessment were performed. Qualitative analysis was performed for SRs and a frequentist random-effects model NMA was performed for RCTs.

RESULTS

Totally, 86 SRs and 76 RCTs were included. Alirocumab (77/86 [90%]) and evolocumab (73/86 [85%]) were mostly analyzed. Associations from SRs (35/42 [83%]) and the updated NMA indicated PCSK9i benefit on major adverse cardiovascular events (MACEs). Reductions were also noted for cerebrovascular events (47/66 [71%]), coronary revascularization (29/33 [88%]) and myocardial infarction (41/63 [65%]). Alirocumab was associated with reductions on all-cause mortality (RR=0.82, 95%CI [0.72,0.94]). Data on any CV event reduction were conflicting (7/16 [44%]). Inclisiran appeared effective only on MACEs (RR=0.76, 95%CI [0.61,0.94]). No reductions in heart failure were observed (0/16). No increases were identified between PCSK9i and any (0/35) or serious adverse events (0/52). However, PCSK9i were associated with injection-site reactions (20/28 [71%]).

CONCLUSION

PCSK9i appeared to be effective in CV outcomes and their clinical application was generally safe.

Geranylgeranyl isoprenoids and hepatic Rap1a regulate basal and statin-induced expression of PCSK9

LDL-C lowering is the main goal of atherosclerotic cardiovascular disease prevention, and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition is now a validated therapeutic strategy that lowers serum LDL-C and reduces coronary events. Ironically, the most widely used medicine to lower cholesterol, statins, has been shown to increase circulating PCSK9 levels, which limits their efficacy. Here, we show that geranylgeranyl isoprenoids and hepatic Rap1a regulate both basal and statin-induced expression of PCSK9 and contribute to LDL-C homeostasis. Rap1a prenylation and activity is inhibited upon statin treatment, and statin-mediated PCSK9 induction is dependent on geranylgeranyl synthesis and hepatic Rap1a. Accordingly, treatment of mice with a small-molecule activator of Rap1a lowered PCSK9 protein and plasma cholesterol and inhibited statin-mediated PCSK9 induction in hepatocytes. The mechanism involves inhibition of the downstream RhoA-ROCK pathway and regulation of PCSK9 at the post-transcriptional level. These data further identify Rap1a as a novel regulator of PCSK9 protein and show that blocking Rap1a prenylation through lowering geranylgeranyl levels contributes to statin-mediated induction of PCSK9.

Unusual effects of PCSK9 E670G (rs505151) variation in patients with in-stent restenosis: Variable effects on restenosis risk according to concomitant chronic conditions

Recent reports showing that neo-atherosclerosis formation in stented coronary artery is characterized by the accumulation of lipid-laden macrophages within the neointima has strengthened the possibility that elevated low-density lipoprotein (LDL)-cholesterol may be a risk factor for in-stent restenosis (ISR). Protein Convertase Subtilisin/Kexin-9 (PCSK9) protein plays an important role in cholesterol metabolism by degrading of LDL receptors. The gain-of-function E670G (rs505151) mutation of the PCSK9 gene is a well-known genetic risk factor for hypercholesterolemia. This study evaluated for the first time the association of the E670G variation with the serum lipids, PCSK9 levels and concomitant diseases on the ISR risk. The study included 109 ISR, and 82 Non-ISR patients, based on the results of coronary angiography. Genotypes were determined using the real-time PCR and serum PCSK9 levels were measured by ELISA technique. The rare G allele of PCSK9 E670G (p < 0.05), hyperlipidemia (HL) (p < 0.001), and type 2 diabetes (T2DM) (p < 0.01) were associated with increased risk for ISR. In hyperlipidemic conditions, the E670G-G allele was associated with hypercholesterolemia and a higher risk of ISR (p < 0.001), while the E670G-AA genotype has been associated with a high prevalence of T2DM and hypertension. In addition, diabetic ISRs had higher serum PCSK9 levels (p < 0.05) and the E670G-AA genotype was associated with increased levels of diabetes markers. Our results indicated that the unusual effects of both G allele and AA genotype of the PCSK9 E670G variation may be involved in the risk of ISR in association with concomitant metabolic diseases.

The Effect of PCSK9 Inhibitors on LDL-C Target Achievement in Patients with Homozygous Familial Hypercholesterolemia: A Retrospective Cohort Analysis

INTRODUCTION

Achieving target low-density lipoprotein-cholesterol (LDL-C) levels remains challenging when treating homozygous familial hypercholesterolemia (HoFH). Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) are prescribed in addition to statins and ezetimibe, but patients' response varies and depends on residual low-density lipoprotein receptor (LDLR) function.

METHODS

A multicenter, retrospective observational analysis evaluated LDL-C target achievement in response to PCSK9i treatment in 28 patients with HoFH from the Middle East/North Africa region. Effect of genotype was investigated. Demographic and clinical information was retrospectively obtained from medical records. Patient response to PCSK9i treatment was assessed by calculating percentage changes in lipid levels from pre-PCSK9i treatment baseline to most recent follow-up visit where patients were recorded as receiving PCSK9i on top of standard of care lipid-lowering therapies (LLTs; i.e., statins/ezetimibe) and assessing European Atherosclerosis Society (EAS) target achievement up to January 31, 2022. Lowest LDL-C level while receiving PCSK9i was identified.

RESULTS

The cohort (n = 28) had a mean age (standard deviation; SD) of 22.8 (9.8) years (n = 28) and was 51% female (n = 27). Baseline LDL-C data were available in 24/28 (85.7%) patients (mean [SD] 14.0 [3.0] mmol/L). Median (interquartile range) duration of PCSK9i treatment was 12.0 months (4.0-19.1) months and mean (SD) % change in LDL-C after PCSK9i treatment was - 8.6% (12.1). LDL-C reduction from baseline was below 15% in 17/24 patients (70.8%). In the full cohort, mean (SD) minimum LDL-C during PCSK9i treatment was 11.9 (2.8; n = 28) mmol/L. No patient achieved EAS target LDL-C while receiving PCSK9i; genotype analysis suggested LDLR-null/null patients were most refractory to PCSK9i.

CONCLUSION

Response to PCSK9i was minimal in this cohort of patients with HoFH. No patients achieved EAS LDL-C targets, and most failed to reach the EAS-recommended 15% LDL-C reduction for PCSK9i therapy continuation. These results suggest additional LLTs are necessary to achieve LDL-C targets in HoFH.

Unveiling Familial Hypercholesterolemia-Review, Cardiovascular Complications, Lipid-Lowering Treatment and Its Efficacy

Familial hypercholesterolemia (FH) is a genetic disorder primarily transmitted in an autosomal-dominant manner. We distinguish two main forms of FH, which differ in the severity of the disease, namely homozygous familial hypercholesterolemia (HoFH) and heterozygous familial hypercholesterolemia (HeFH). The characteristic feature of this disease is a high concentration of low-density lipoprotein cholesterol (LDL-C) in the blood. However, the level may significantly vary between the two mentioned types of FH, and it is decidedly higher in HoFH. A chronically elevated concentration of LDL-C in the plasma leads to the occurrence of certain abnormalities, such as xanthomas in the tendons and skin, as well as corneal arcus. Nevertheless, a significantly more severe phenomenon is leading to the premature onset of cardiovascular disease (CVD) and its clinical implications, such as cardiac events, stroke or vascular dementia, even at a relatively young age. Due to the danger posed by this medical condition, we have investigated how both non-pharmacological and selected pharmacological treatment impact the course of FH, thereby reducing or postponing the risk of clinical manifestations of CVD. The primary objective of this review is to provide a comprehensive summary of the current understanding of FH, the effectiveness of lipid-lowering therapy in FH and to explain the anatomopathological correlation between FH and premature CVD development, with its complications.

Alternative lipid lowering strategies: State-of-the-art review of red yeast rice

Red yeast rice (RYR) is an entirely natural product that originates from the fermentation of white rice (Oryza sativa) with a yeast, mainly Monascus Purpureus, and has been part of traditional Chinese medicine and diet since ancient times. It has generated great interest in recent years in the context of cardiovascular (CV) prevention due to its ability to inhibit endogenous cholesterol production, helping to achieve and maintain optimal plasma lipid concentrations. This review aims to make an extensive 360-degree assessment and summary of the whole currently available scientific evidence about RYR, starting with its biochemical composition, passing through a historical reconstruction of all the studies that have evaluated its efficacy and safety in cholesterol-lowering action, with a focus on CV outcomes, and ultimately addressing its other relevant clinical effects. We also discuss its possible therapeutic role, alone or in combination with other nutraceuticals, in different clinical scenarios, taking into account the positions of major scientific documents on the issue, and describe the articulate legal controversies that have characterized the regulation of its use up to the present day. RYR preparations have been proven safe and effective in improving lipid profile, with a potential role in reducing cardiovascular risk. They can be considered as additional supportive agents in the armamentarium of lipid-modifying therapies.

Efficacy and Safety of Alirocumab and Evolocumab as Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) Inhibitors in Familial Hypercholesterolemia: A Systematic Review and Meta-Analysis

BACKGROUND

Familial hypercholesterolemia (FH) is a prevalent and potentially fatal illness that causes a substantial elevation in low-density lipoprotein cholesterol (LDL-C).

OBJECTIVE

The aim of this study was to investigate the effects of monoclonal antibodies alirocumab and evolocumab on LDL-C and other lipid parameters, as well as their safety in familial hypercholesterolemia patients.

METHODS

A comprehensive search was done on PubMed/MEDLINE, EMBASE, Web of Science (WOS/ ISI), Scopus, ClinicalTrials (www.

CLINICALTRIALS

gov), and conferences/ congress research papers. Random effect models were used to calculate mean differences (%) and risk ratios (RRs), and confidence intervals (95%).

RESULTS

Ten studies (n=1489 patients) were included in this study. PCSK9 inhibitors decreased the levels of LDL-C by -49.59% (95%CI -55.5%, -43.67%) as compared to placebo. They also didn't alter the Treatment-Emergent Adverse Event (TEAE) and neuronal events by RR 0.92 (0.75, 1.13) and 1.31 (0.66, 2.59), respectively. PCSK9 inhibitors were effective and safe in treating patients with FH.

CONCLUSION

There was high-quality evidence showing that monoclonal antibodies (alirocumab & evolocumab) lower LDL-C (GRADE: high), lipoprotein (a) (GRADE: High), triglycerides (TG) (GRADE: High), total cholesterol (GRADE: High), non-high-density lipoprotein cholesterol (non- HDL-C) (GRADE: Moderate), and apolipoprotein B (GRADE: High), and increase the HDL-C (GRADE: High) as well as apolipoprotein A1 (GRADE: High). Comparing PCSK9 inhibitors against placebo, neither TEAE (GRADE: high) nor neuronal events (GRADE: moderate) were changed.

Polymorphisms rs562556 and rs2479409 of the PCSK9 gene associated with obesity and cardiovascular disease

OBJECTIVE

The primary objective was to comprehensively assess the association between single nucleotide polymorphisms (rs562556 and rs2479409) in the PCSK9 gene with biochemical parameters - C-reactive protein (CRP), glucose (GLU), triglyceride (TAG), low-density lipoprotein cholesterol (LDL CHOL), non-high-density lipoprotein cholesterol (non HDL CHOL), high-density lipoprotein cholesterol (HDL CHOL), cholesterol (CHOL), and anthropometric parameters (visceral fat), overweight/obesity and cardiovascular risk.

METHODS

A total of 71 women aged 23-64 years were divided into three groups based on body mass index (BMI). BMI ≥ 25/≥ 30 kg/m2 was the criterion for assessment of overweight/obesity. Anthropometric, biochemical and genetic examinations were performed on the probands. Changes in markers in each group and their association with cardiovascular risk were monitored.

RESULTS

We can conclude that in our study population we observed differences between the BMI categories for biochemical markers (CRP, LDL CHOL, non HDL CHOL, HDL CHOL, LDL CHOL) and anthropometric marker (visceral fat). Atherogenic index of plasma (AIP), Castelli's Risk Index I (CRI-I) and atherogenic coefficient (AC) confirmed high cardiovascular risk for the obese women category (0.045); (< 0.013); (< 0.010). Genotype and allele frequencies for the PCSK9 gene in the overweight and obese groups showed higher allele frequencies of allele A for both polymorphisms of the gene.

CONCLUSIONS

PCSK9 gene expression is associated with biological processes such as lipid metabolism and inflammation. Cholesterol-lowering therapies are the gold standard for reducing the risk of cardiovascular mortality and morbidity. Administration of monoclonal antibodies (mAbs) against PCSK9 is a novel lipid-lowering therapeutic approach in adults to reduce the risk of cardiovascular disease.

Geranylgeranyl Isoprenoids and Hepatic Rap1a Regulate Basal and Statin-Induced Expression of PCSK9

Low-density lipoprotein cholesterol (LDL-C) lowering is the main goal of atherosclerotic cardiovascular disease prevention, and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition is now a validated therapeutic strategy that lowers serum LDL-C and reduces coronary events. Ironically, the most widely used medicine to lower cholesterol, statins, has been shown to increase circulating PCSK9 levels, which limits their efficacy. Here, we show that geranylgeranyl isoprenoids and hepatic Rap1a regulate both basal and statin induced expression of PCSK9 and contribute to LDL-C homeostasis. Rap1a prenylation and activity is inhibited upon statin treatment, and statin mediated PCSK9 induction is dependent on geranylgeranyl synthesis and hepatic Rap1a. Accordingly, treatment of mice with a small molecule activator of Rap1a lowered PCSK9 protein and plasma cholesterol and inhibited statin mediated PCSK9 induction in hepatocytes. The mechanism involves inhibition of the downstream RhoA-ROCK pathway and regulation of PCSK9 at the post transcriptional level. These data further identify Rap1a as a novel regulator of PCSK9 protein and show that blocking Rap1a prenylation through lowering geranylgeranyl levels contributes to statin-mediated induction of PCSK9.

The association between circulatory, local pancreatic PCSK9 and type 2 diabetes mellitus: The effects of antidiabetic drugs on PCSK9

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a potent modulator of cholesterol metabolism and plays a crucial role in the normal functioning of pancreatic islets and the progression of diabetes. Islet autocrine PCSK9 deficiency can lead to the enrichment of low-density lipoprotein (LDL) receptor (LDLR) and excessive LDL cholesterol (LDL-C) uptake, subsequently impairing the insulin secretion in β-cells. Circulatory PCSK9 levels are primarily attributed to hepatocyte secretion. Notably, anti-PCSK9 strategies proposed for individuals with hypercholesterolemia chiefly target liver-derived PCSK9; however, these anti-PCSK9 strategies have been associated with the risk of new-onset diabetes mellitus (NODM). In the current review, we highlight a new direction in PCSK9 inhibition therapy strategies: screening candidates for anti-PCSK9 from the drugs used in type 2 diabetes mellitus (T2DM) treatment. We explored the association between circulating, local pancreatic PCSK9 and T2DM, as well as the relationship between PCSK9 monoclonal antibodies and NODM. We discussed the emergence of artificial and natural drugs in recent years, exhibiting dual benefits of antidiabetic activity and PCSK9 reduction, confirming that the diverse effects of these drugs may potentially impact the progression of diabetes and associated disorders, thereby introducing novel avenues and methodologies to enhance disease prognosis.

Appropriateness of Dyslipidemia Management Strategies in Post-Acute Coronary Syndrome: A 2023 Update

It has been consistently demonstrated that circulating lipids and particularly low-density lipoprotein cholesterol (LDL-C) play a significant role in the development of coronary artery disease (CAD). Several trials have been focused on the reduction of LDL-C values in order to interfere with atherothrombotic progression. Importantly, for patients who experience acute coronary syndrome (ACS), there is a 20% likelihood of cardiovascular (CV) event recurrence within the two years following the index event. Moreover, the mortality within five years remains considerable, ranging between 19 and 22%. According to the latest guidelines, one of the main goals to achieve in ACS is an early improvement of the lipid profile. The evidence-based lipid pharmacological strategy after ACS has recently been enhanced. Although novel lipid-lowering drugs have different targets, the result is always the overexpression of LDL receptors (LDL-R), increased uptake of LDL-C, and lower LDL-C plasmatic levels. Statins, ezetimibe, and PCSK9 inhibitors have been shown to be safe and effective in the post-ACS setting, providing a consistent decrease in ischemic event recurrence. However, these drugs remain largely underprescribed, and the consistent discrepancy between real-world data and guideline recommendations in terms of achieved LDL-C levels represents a leading issue in secondary prevention. Although the cost-effectiveness of these new therapeutic advancements has been clearly demonstrated, many concerns about the cost of some newer agents continue to limit their use, affecting the outcome of patients who experienced ACS. In spite of the fact that according to the current recommendations, a stepwise lipid-lowering approach should be adopted, several more recent data suggest a "strike early and strike strong" strategy, based on the immediate use of statins and, eventually, a dual lipid-lowering therapy, reducing as much as possible the changes in lipid-lowering drugs after ACS. This review aims to discuss the possible lipid-lowering strategies in post-ACS and to identify those patients who might benefit most from more powerful treatments and up-to-date management.

A proteomic approach for investigating the pleiotropic effects of statins in the atherosclerosis risk in communities (ARIC) study

BACKGROUND

Statins are prescribed to reduce LDL-c and risk of CVD. Statins have pleiotropic effects, affecting pathophysiological functions beyond LDL-c reduction. We compared the proteome of statin users and nonusers (controls). We hypothesized that statin use is associated with proteins unrelated to lipid metabolism.

METHODS

Among 10,902 participants attending ARIC visit 3 (1993-95), plasma concentrations of 4955 proteins were determined using SOMAlogic's DNA aptamer-based capture array. 379 participants initiated statins within the 2 years prior. Propensity scores (PS) were calculated based on visit 2 (1990-92) LDL-c levels and visit 3 demographic/clinical characteristics. 360 statin users were PS matched to controls. Log2-transformed and standardized protein levels were compared using t-tests, with false discovery rate (FDR) adjustment for multiple comparisons. Analyses were replicated in visit 2.

RESULTS

Covariates were balanced after PS matching, except for higher visit 3 LDL-c levels among controls (125.70 vs 147.65 mg/dL; p < 0.0001). Statin users had 11 enriched and 11 depleted protein levels after FDR adjustment (q < 0.05). Proteins related and unrelated to lipid metabolism differed between groups. Results were largely replicated in visit 2.

CONCLUSION

Proteins unrelated to lipid metabolism differed by statin use. Pending external validation, exploring their biological functions could elucidate pleiotropic effects of statins.

SIGNIFICANCE

Statins are the primary pharmacotherapy for lowering low-density lipoprotein (LDL) cholesterol and preventing cardiovascular disease. Their primary mechanism of action is through inhibiting the protein 3hydroxy-3-methylglutaryl CoA reductase (HMGCR) in the mevalonate pathway of LDL cholesterol synthesis. However, statins have pleiotropic effects and may affect other biological processes directly or indirectly, with hypothesized negative and positive effects. The present study contributes to identifying these pathways by comparing the proteome of stain users and nonusers with propensity score matching. Our findings highlight potential biological mechanisms underlying statin pleiotropy, informing future efforts to identify statin users at risk of rare nonatherosclerotic outcomes and identify health benefits of statin use independent of LDL-C reduction.

Proprotein Convertase Subtilisin/Kexin 9 as a Modifier of Lipid Metabolism in Atherosclerosis

Despite being the most common treatment strategy in the management of atherosclerosis and subsequent cardiovascular disease, classical statin therapy has certain disadvantages, including numerous side effects. In addition, a regimen with daily administration of the drug is hard to comply with. Thus, there is a need for modern and more efficient therapeutic strategies in CVD treatment. There is extensive evidence indicating that PCSK9 promotes atherogenesis through a variety of mechanisms. Thus, new treatment methods can be developed that prevent or alleviate atherosclerotic cardiovascular disease by targeting PCSK9. Comprehensive understanding of its atherogenic properties is a necessary precondition for the establishment of new therapeutic strategies. In this review, we will summarize the available data on the role of PCSK9 in the development and progression of atherosclerosis. In the last section, we will consider existing PCSK9 inhibitors.

Mechanisms of unusual response to lipid-lowering therapy: PCSK9 inhibition

The efficacy of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition has broadened lipid-lowering therapy thus providing decreased risk in atherosclerotic cardiovascular disease. Unfortunately, the widespread use of PCSK9 inhibitors (PCSK9i), ie, monoclonal antibodies, has led to the findings of unusual responsiveness, ie, a phenomenon defined as an LDL-C reduction of <30% vs the average LDL-C reduction efficacy of 50-60%. This unusual responsiveness to PCSK9i is attributable to several factors, ie, lack of adherence, impaired absorption, poor distribution or early elimination as well as abnormal effects of PCSK9i in the presence of anti-antibodies or mutations in PCSK9 and LDLR. Unexpectedly increased lipoprotein (Lp)(a) also appear to contribute to the unusual responsiveness scenario. Identification of these responses and mechanisms underlying them are essential for effective management of LDL-C and cardiovascular risk. In this review, we describe plausible reasons underlying this phenomenon supported by findings of clinical trials. We also elaborate on the need for education and regular follow-up to improve adherence. Collectively, the review provides a summary of the past, present, and future of mechanisms and countermeasures revolving around unusual responses to PCSK9i therapy.

Sex differences in LDL-C response to PCSK9 inhibitors: A real world experience

BACKGROUND

Previous studies have shown the efficacy of PCSK9 inhibitors (PCSK9i) in lowering LDL-C. One clinical trial with alirocumab suggested that the LDL-C reduction effect is larger in men than women. In contrast, none of the studies with evolocumab have observed a difference in the treatment effect between men and women. However, sex differences data from real life experience is lacking. In addition, the difference in LDL-C response to PCSK9i between pre- and post-menopausal women has not been investigated so far.

OBJECTIVES

To compare the relative change in LDL-C following the introduction of a PCSK9i in a real-life clinical setting according to sex and menopausal status.

METHODS

All patients were recruited at the IRCM lipid clinic. Lipid profiles before and after the introduction of PCSK9i were available in the medical file for 259 patients (160 men and 99 women (72 post-menopausal, 20 pre-menopausal and 7 unknown menopausal status).

RESULTS

We observed a significant difference in relative LDL-C change between men (-70%) and women (-59%), p<0.0001. However, no difference was observed between pre-menopausal (-58%) and post-menopausal (-58%) women. In a linear regression model, sex remains a significant predictor of the response to PCSK9i after correction for confounding factors such as statin intensity (beta coefficient=-0.245, p<0.0001).

CONCLUSION

We observed a greater relative LDL-C response to PCSK9i in men than in women in a real-life clinical context. However, it is still unknown whether this difference in LDL-C change between men and women translates into a meaningful difference on long-term cardiovascular risk.

Genetic Spectrum of Familial Hypercholesterolaemia in the Malaysian Community: Identification of Pathogenic Gene Variants Using Targeted Next-Generation Sequencing

Familial hypercholesterolaemia (FH) is caused by mutations in lipid metabolism genes, predominantly in low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), proprotein convertase subtilisin/kexin-type 9 (PCSK9) and LDL receptor adaptor protein 1 (LDLRAP1). The prevalence of genetically confirmed FH and the detection rate of pathogenic variants (PV) amongst clinically diagnosed patients is not well established. Targeted next-generation sequencing of LDLR, APOB, PCSK9 and LDLRAP1 was performed on 372 clinically diagnosed Malaysian FH subjects. Out of 361 variants identified, 40 of them were PV (18 = LDLR, 15 = APOB, 5 = PCSK9 and 2 = LDLRAP1). The majority of the PV were LDLR and APOB, where the frequency of both PV were almost similar. About 39% of clinically diagnosed FH have PV in PCSK9 alone and two novel variants of PCSK9 were identified in this study, which have not been described in Malaysia and globally. The prevalence of genetically confirmed potential FH in the community was 1:427, with a detection rate of PV at 0.2% (12/5130). About one-fourth of clinically diagnosed FH in the Malaysian community can be genetically confirmed. The detection rate of genetic confirmation is similar between potential and possible FH groups, suggesting a need for genetic confirmation in index cases from both groups. Clinical and genetic confirmation of FH index cases in the community may enhance the early detection of affected family members through family cascade screening.

Prognostic Impacts of LL-37 in Relation to Lipid Profiles of Patients with Myocardial Infarction: A Prospective Cohort Study

Background. In vivo studies show that LL-37 inhibits the progression of atherosclerosis and predicts a lower risk of recurrent ischemia in patients with acute myocardial infarction (AMI), which could be mediated by the modulation of lipid metabolism. The current study aimed to investigate the effects of various lipid contents on the prognostic impacts of LL-37 in patients with AMI. Methods. A total of 1567 consecutive AMI patients were prospectively recruited from March 2017 to January 2020. Patients were firstly stratified into two groups by the median level of LL-37 and then stratified by levels of various lipid contents and proprotein convertase subtilisin/kexin type 9 (PCSK9). Cox regression with multiple adjustments was performed to analyze associations between LL-37, lipid profiles, PCSK9, and various outcomes. The primary outcome was major adverse cardiovascular event (MACE), a composite of all-cause death, recurrent MI, and ischemic stroke. Results. During a median follow-up of 786 (726−1107) days, a total of 252 MACEs occurred. A high level of LL-37 was associated with lower risk of MACE in patients with elevated lipoprotein(a) (≥300 mg/L, hazard ratio (HR): 0.49, 95% confidence interval (CI): 0.29−0.86, p = 0.012) or PCSK9 levels above the median (≥47.4 ng/mL, HR: 0.57, 95% CI: 0.39−0.82, p < 0.001), which was not observed for those without elevated lp(a) (<300 mg/L, HR: 0.96, 95% CI: 0.70−1.31, p = 0.781, pinteraction = 0.035) or PCSK9 (<47.4 ng/mL, HR: 1.02, 95% CI: 0.68−1.54, p = 0.905, pinteraction = 0.032). Conclusions. For patients with AMI, a high level of LL-37 was associated with lower ischemic risk among patients with elevated lp(a) and PCSK9.

Relationship between Serum Proprotein Convertase Subtilisin/Kexin Type 9 Concentration and Prevalence of Coronary Artery Calcium in a Community-Based Sample of Japanese Men

AIMS

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a promising new target for reducing low-density lipoprotein cholesterol (LDL-C) and cardiovascular events in high-risk patients. However, the influence of circulating PCSK9 concentration on atherosclerotic plaque formation in the general population remains unknown. We assessed the relationship between serum PCSK9 concentration and coronary artery calcium (CAC) prevalence in the general population.

METHODS

Community-dwelling Japanese men (n=622) aged 46-82 years without a history of cardiovascular disease and lipid-lowering medications were included. Serum PCSK9 concentration and CAC score were measured using the Agatston method, and the multivariable analysis was used to assess their association. CAC was defined as an Agatston score of ＞10. We conducted further analysis stratified by age (＜60, 60-69, and ≥ 70 years).

RESULTS

The average age, LDL-C, and median serum PCSK9 concentration were 68 years, 122 mg/dL, and 240 ng/mL, respectively. After multivariable adjustment for traditional cardiovascular risk factors, no significant association was observed between serum PCSK9 concentration and CAC prevalence (adjusted relative risk [aRR] 1.05, 95% confidence interval [CI] 0.97-1.13). With age stratification, serum PCSK9 concentration was significantly associated with CAC prevalence in men aged ＜60 years (aRR 1.38, 95% CI 1.01-1.88) but not in men aged 60-69 years (aRR 0.96, 95% CI 0.85-1.10) or ≥ 70 years (aRR 1.08, 95% CI 0.99-1.19).

CONCLUSIONS

A higher serum PCSK9 concentration was associated with a higher CAC prevalence in men aged ＜60 years, which was independent of traditional cardiovascular risk factors.

Impact of conventional lipid-lowering therapy on circulating levels of PCSK9: protocol for a systematic review and meta-analysis of randomised controlled trials

INTRODUCTION

Conventional lipid-lowering agents, including statins, ezetimibe, fibrates, bile acid sequestrants, nicotinic acid, bempedoic acid and Omega-3, are essential to the management of dyslipidaemia. However, these agents have been shown to increase the level of plasma proprotein convertase subtilisin/kexin 9 (PCSK9), a serine protease associated with increased cardiovascular risk. This review aims to investigate the impact of commonly available conventional lipid-lowering agents on circulating PCSK9 levels and lipid profiles.

METHODS AND ANALYSIS

This protocol is conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols guidelines. A systematic search will be conducted in the following databases: MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE, Web of Science, SCOPUS and ScienceDirect. Additional information will be retrieved from clinical trial registries or from reference list searches. Published and peer-reviewed randomised controlled trials with adults receiving statin, ezetimibe, fibrate, bile acid sequestrant, nicotinic acid, bempedoic acid or Omega-3 monotherapy or in combination for at least 2 weeks, with availability of plasma PCSK9 at the beginning and end of treatment or the net changes in values, will be included. Study selection, data extraction and assessment of the risk of bias will be independently conducted by two investigators. Continuous data will be presented as a standardised mean difference with 95% confidence interval (CI) and dichotomous data as risk ratios with 95% CI. Subgroup analysis and sensitivity analysis will be performed when sufficient studies are included. Publication bias will be assessed with a funnel plot and Egger's test.

ETHICS AND DISSEMINATION

Ethics approval is not required as this review will only include data from published sources. The results will be published in a peer-reviewed journal.

PATIENT AND PUBLIC INVOLVEMENT

No patient or members of the general public are involved.

PROSPERO REGISTRATION NUMBER

CRD42022297942.

Effects of statins on the inducible degrader of low-density lipoprotein receptor in familial hypercholesterolemia

The inducible degrader of low-density lipoprotein receptor (IDOL) is an E3 ubiquitin ligase involved in the post-transcriptional regulation of LDL receptor (LDLR). Statins lower plasma LDL by activating transcription of hepatic LDLR expression, and we have determined whether statins modulate IDOL expression and influence LDLR protein abundance. IDOL expression in monocytes and serum IDOL level was determined in statin-treated familial hypercholesterolemia (FH) patients and compared with control subjects. Serum IDOL level was also evaluated in a group of untreated FH patients before and after the initiation of statin. The mechanism underlying the inhibitory effect of statin on IDOL expression was investigated in vitro. In statin-treated FH patients, serum IDOL level and its expression in monocytes was reduced compared with control (P < 0.05). In contrast, untreated FH patients had higher serum levels of IDOL and proprotein convertase subtilisin/kexintype 9 (PCSK9) than control (P < 0.05), and serum IDOL level decreased after statin therapy (P < 0.05) whereas an increase was observed in PCSK9 level (P < 0.01). In vitro, atorvastatin significantly decreased IDOL abundance in a dose-dependent manner in cultured macrophages and hepatocytes with a concomitant increase in LDLR expression. The transcription of IDOL was restored by adding either an LXR agonist T0901317 or oxysterol 22(R)-hydroxycholesterol, indicating that statin inhibited IDOL expression by reducing LXR activation. The LXR-IDOL-LDLR axis can be modulated by statins in vitro and in vivo. Statins inhibit IDOL expression by reducing LXR activation and upregulate LDLR, and statins exert the opposite effect on IDOL and PCSK9.

A mathematical model of in vitro hepatocellular cholesterol and lipoprotein metabolism for hyperlipidemia therapy

Cardiovascular diseases associated with high cholesterol (hypercholesterolemia) and low-density lipoproteins (LDL) levels are significant contributors to total mortality in developing and developed countries. Mathematical modeling of LDL metabolism is an important step in the development of drugs for hypercholesterolemia. The aim of this work was to develop and to analyze an integrated mathematical model of cholesterol metabolism in liver cells and its interaction with two types of drugs, statins and PCSK9 inhibitors. The model consisted of 21 ordinary differential equations (ODE) describing cholesterol biosynthesis and lipoprotein endocytosis in liver cells in vitro. The model was tested for its ability to mimic known biochemical effects of familial hypercholesterolemia, statin therapy, and PCSK9 inhibitors. The model qualitatively reproduced the well-known biology of cholesterol regulation, which confirms its potential for minimizing cellular research in initial testing of new drugs for cardiology.

Di’ao Xinxuekang Capsule Improves the Anti-Atherosclerotic Effect of Atorvastatin by Downregulating the SREBP2/PCSK9 Signalling Pathway

Statins are the first choice for lowering low-density lipoprotein cholesterol (LDL-C) and preventing atherosclerotic cardiovascular disease (ASCVD). However, statins can also upregulate proprotein convertase subtilisin/kexin type 9 (PCSK9), which in turn might limits the cholesterol-lowering effect of statins through the degradation of LDL receptors (LDLR). Di’ao Xinxuekang (DXXK) capsule, as a well-known traditional Chinese herbal medicine for the prevention and treatment of coronary heart disease, can alleviate lipid disorders and ameliorate atherosclerosis in atherosclerosis model mice and downregulate the expression of PCSK9. In this study, we further explored whether DXXK has a synergistic effect with atorvastatin (ATO) and its underlying molecular mechanism. The results showed that both ATO monotherapy (1.3 mg/kg) and ATO combined with DXXK therapy significantly lowered serum lipid levels and reduced the formation of atherosclerotic plaques and the liver lipid accumulation. Moreover, compared with ATO monotherapy, the addition of DXXK (160 mg/kg) to the combination therapy further lowered LDL-C by 15.55% and further reduced the atherosclerotic plaque area by 25.98%. In addition, the expression of SREBP2, PCSK9 and IDOL showed a significant increase in the model group, and the expression of LDLR was significantly reduced; however, there were no significant differences between the ATO (1.3 mg/kg) and the model groups. When ATO was combined with DXXK, the expression of LDLR was significantly increased and was higher than that of the model group and the expression of SREBP2 and PCSK9 in the liver was also significantly inhibited. Moreover, it can be seen that the expression of SREBP2 and PCSK9 in the combination treatment group was significantly lower than that in the ATO monotherapy group (1.3 mg/kg). Besides, the expression of IDOL mRNA in each treatment group was not significantly different from that of the model group. Our study suggests that DXXK might have a synergistic effect on the LDL-C lowering and antiatherosclerosis effects of ATO through the SREBP2/PCSK9 pathway. This indicates that a combination of DXXK and ATO may be a new treatment for atherosclerosis.

PCSK9 Plasma Levels Are Associated with Mechanical Vascular Impairment in Familial Hypercholesterolemia Subjects without a History of Atherosclerotic Cardiovascular Disease: Results of Six-Month Add-On PCSK9 Inhibitor Therapy

Proprotein convertase subtilisin/kexin type-9 (PCSK9) is a key regulator of low-density lipoprotein (LDL) metabolism involved in the degradation of the low-density lipoprotein receptor (LDLR) through complex mechanisms. The PCSK9 plasma levels change according to lipid lowering therapy (LLT). Few data exist regarding the role of PCSK9 in vascular damage. We aimed to evaluate the impact of PCSK9 plasma levels on pulse wave velocity (PWV) and the effect of PCSK9 inhibitors (PCSK9-i) on circulating PCSK9 and PWV in a cohort of heterozygous familial hypercholesterolemia (HeFH) subjects. In a previous step, HeFH patients were enrolled and LLT was prescribed according to guidelines. Biochemical analyses and PWV assessment were performed at baseline (T0), after 6 months of high-efficacy statin plus ezetimibe (T1) and after 6 months of PCSK9-i (T2). The PCSK9 levels were evaluated in 26 selected HeFH subjects at the three time points and 26 healthy subjects served as controls for the reference value for PCSK9 plasma levels. The PWV values decreased at each time point in HeFH subjects after LLT starting (8.61 ± 2.4 m/s, −8.7%; p < 0.001 vs. baseline at T1, and 7.9 ± 2.1 m/s, −9.3%; p < 0.001 vs. both T1 and baseline) and it was correlated to PCSK9 (r = 0.411, p = 0.03). The PCSK9 levels increased on statin/EZE therapy (+42.8% at T1) while it decreased after PCSK9-i was started (−34.4% at T2). We noted a significant relationship between PCSK9 levels and PWV changes at T1 and T2. In conclusion, PCSK9 levels were associated with baseline PWV values in HeFH subjects; moreover, we found that PCSK9 level variations seemed to be correlated with PWV changes on LLT. A longer observation time and wider sample size are needed to assess the potential role of PCSK9 plasma levels on the vascular function and remodelling, and to clarify the effects of PCSK9-i in these pathways.

Ramadan Intermittent Fasting Is Associated with Changes in Circulating Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) in Metabolically Healthy Obese Subjects

Background and Objectives: Dietary modification is the principal approach to the management of hyperlipidemia in adults. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a key regulator of plasma cholesterol and a target for novel lipid-lowering pharmacotherapies. This study aimed to explore how circulating levels of PCSK9 changed during Ramadan intermittent fasting in metabolically healthy obese subjects. Materials and Methods: This cross-sectional study used convenience sampling to recruit 55 overweight and obese participants (22 females and 33 males) who observed Ramadan fasting. Body weight and composition, glucoregulatory factors, serum PCSK9 concentration, dietary intake, and physical activity were assessed 1 week before and at the end of Ramadan fasting. Results: The median (interquartile range) age was 35 (22) years, and body mass index was 30.2 (5.4). We found significant (p < 0.05) increases in serum levels of PCSK9, serum insulin, insulin resistance, and leptin at the end of Ramadan compared with pre-fasting levels. Significant (p < 0.05) reductions in body weight, waist circumference, systolic and diastolic blood pressure, total cholesterol, triglycerides, high-density lipoprotein cholesterol, and adiponectin were also observed at the end of Ramadan. Conclusions: Observing Ramadan fasting was associated with increased PCSK9 levels in metabolically healthy obese subjects. The complex relationships between PCSK9 and insulin resistance and dysregulation of adipokine secretion in relation to dietary and lifestyle modifications during Ramadan warrant further research.

Emerging Insights on the Diverse Roles of Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) in Chronic Liver Diseases: Cholesterol Metabolism and Beyond

Chronic liver diseases are commonly associated with dysregulated cholesterol metabolism. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a serine protease of the proprotein convertase family that is mainly synthetized and secreted by the liver, and represents one of the key regulators of circulating low-density lipoprotein (LDL) cholesterol levels. Its ability to bind and induce LDL-receptor degradation, in particular in the liver, increases circulating LDL-cholesterol levels in the blood. Hence, inhibition of PCSK9 has become a very potent tool for the treatment of hypercholesterolemia. Besides PCSK9 limiting entry of LDL-derived cholesterol, affecting multiple cholesterol-related functions in cells, more recent studies have associated PCSK9 with various other cellular processes, including inflammation, fatty acid metabolism, cancerogenesis and visceral adiposity. It is increasingly becoming evident that additional roles for PCSK9 beyond cholesterol homeostasis are crucial for liver physiology in health and disease, often contributing to pathophysiology. This review will summarize studies analyzing circulating and hepatic PCSK9 levels in patients with chronic liver diseases. The factors affecting PCSK9 levels in the circulation and in hepatocytes, clinically relevant studies and the pathophysiological role of PCSK9 in chronic liver injury are discussed.

PCSK9 as a Target for Development of a New Generation of Hypolipidemic Drugs

PCSK9 has now become an important target to create new classes of lipid-lowering drugs. The prevention of its interaction with LDL receptors allows an increase in the number of these receptors on the surface of the cell membrane of hepatocytes, which leads to an increase in the uptake of cholesterol-rich atherogenic LDL from the bloodstream. The PCSK9 antagonists described in this review belong to different classes of compounds, may have a low molecular weight or belong to macromolecular structures, and also demonstrate different mechanisms of action. The mechanisms of action include preventing the effective binding of PCSK9 to LDLR, stimulating the degradation of PCSK9, and even blocking its transcription or transport to the plasma membrane/cell surface. Although several types of antihyperlipidemic drugs have been introduced on the market and are actively used in clinical practice, they are not without disadvantages, such as well-known side effects (statins) or high costs (monoclonal antibodies). Thus, there is still a need for effective cholesterol-lowering drugs with minimal side effects, preferably orally bioavailable. Low-molecular-weight PCSK9 inhibitors could be a worthy alternative for this purpose.

Differential Effects of DPP-4 Inhibitors, Anagliptin and Sitagliptin, on PCSK9 Levels in Patients with Type 2 Diabetes Mellitus who are Receiving Statin Therapy

Aim: Proprotein convertase subtilisin/kexin type 9 (PCSK9) degrades the low-density lipoprotein (LDL) receptor, leading to hypercholesterolemia and cardiovascular risk. Treatment with a statin leads to a compensatory increase in circulating PCSK9 level. Anagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, was shown to decrease LDL cholesterol (LDL-C) levels to a greater extent than that by sitagliptin, another DPP-4 inhibitor, in the Randomized Evaluation of Anagliptin versus Sitagliptin On low-density lipoproteiN cholesterol in diabetes (REASON) trial. We investigated PCSK9 concentration in type 2 diabetes mellitus (T2DM) and the impact of treatment with anagliptin or sitagliptin on PCSK9 level as a sub-analysis of the REASON trial.

Methods: PCSK9 concentration was measured at baseline and after 52 weeks of treatment with anagliptin ( n =122) or sitagliptin ( n =128) in patients with T2DM who were receiving statin therapy. All of the included patients had been treated with a DPP-4 inhibitor prior to randomization.

Results: Baseline PCSK9 level was positively, but not significantly, correlated with LDL-C and was independently associated with platelet count and level of triglycerides. Concomitant with reduction of LDL-C, but not hemoglobin A1c (HbA1c), by anagliptin, PCSK9 level was significantly increased by treatment with sitagliptin (218±98 vs. 242±115 ng/mL, P =0.01), but not anagliptin (233±97 vs. 250±106 ng/mL, P =0.07).

Conclusions: PCSK9 level is independently associated with platelet count and level of triglycerides, but not LDL-C, in patients with T2DM. Anagliptin reduces LDL-C level independent of HbA1c control in patients with T2DM who are on statin therapy possibly by suppressing excess statin-mediated PCSK9 induction and subsequent degradation of the LDL receptor.

PCSK9 inhibitors revisited: Effectiveness and safety of PCSK9 inhibitors in a real-life Spanish cohort

INTRODUCTION

Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) have emerged as a therapeutic option for patients with hypercholesterolemia who do not attain low-density lipoprotein cholesterol (LDL-C) goals and/or are intolerant to other lipid-lowering drugs. Our aim was to analyze the effectiveness and safety of PCSK9i in routine clinical practice and factors related to poor outcomes.

MATERIALS AND METHODS

We conducted an ambispective study in 115 patients who recieved alirocumab or evolocumab, in a tertiary level hospital. From February 2017 to April 2020, patients were recruited and followed up for a median of 20.4 months. The main outcomes were relative reduction in LDL-C, percentage of patients achieving the therapeutic goals established by 2016 ESC/EAS guidelines, incidence of major cardiovascular events (MACEs) and drug-related adverse events (ADRs).

RESULTS

The median LDL-C achieved was 57.0 mg/dL (relative reduction of 59.9% from baseline, p< 0.001). After adjusting for confounders, smaller LDL-C reductions were related to female sex, absence of concomitant lipid-lowering therapy and treatment with alirocumab. Overall, 84.6% of the patients achieved the therapeutic goals. During follow-up, 7 MACEs were detected. ADRs, generally considered mild, affected 38.1% of the participants (mainly mialgias and arthralgias) and triggered discontinuations in 8.7% of cases.

CONCLUSIONS

PCSK9i are effective and safe, although certain factors may influence their effectiveness. Interestingly, our results suggest that alirocumab and evolocumab may not be therapeutic equivalents, as initially suggested.

Acaudina molpadioides mediates lipid uptake by suppressing PCSK9 transcription and increasing LDL receptor in human liver cells

Acaudina molpadioides has been long used as traditional medicinal resources and reported to demonstrate various important bioactivities such as anticoagulation, antithrombosis, anti-hyperglycemia and anticancer. However, its lipid lowering activity is yet to be fully explored. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is an enzyme that enhances the lysosomal degradation of hepatic low density lipoprotein receptor (LDLR) resulting in excessive accumulation of the plasma levels of LDL-cholesterols (LDL-C) which subsequently accelerate atherosclerosis. In the present study, A. molpadioides fractions were subjected to promoter-reporter luciferase assay to determine its role as PCSK9 inhibitors. It was found both fractions (EFA and EFB) reduced the transcriptional activity of PCSK9 promoter. Among the seven 5′end deletion constructs of PCSK9 promoter, fragments D1 (−1,711/−94), D3 (−709/−94) and D4 (−440/−94), were suppressed in the presence of both fractions whereas D2 (−1,214/−94), and, D6 (−351/−94) as well as D7 (−335/−94) were inhibited only by EFA and EFB, respectively. Further transcription factor binding sites prediction using MatInspector software discovered various potential cis-regulatory elements namely, PPAR, KLFs, RBPJ-kappa and SREBP that may potentially be involved in ameliorating the transcriptional activity of PCSK9. Immunofluorescence staining was used to evaluate the effects of both fractions on LDL-C and LDLR. Results showed that levels of LDL-C uptake in EFA-treated cells were 69.1% followed by EFB at 32.6%, as compared to untreated control after 24 h treatment. The LDLR protein distribution was induced by 62.41% and 32.2%, which corresponded to an increase in LDL-C uptake in both EFA and EFB treatment, respectively. Hence, the inhibition of PCSK9 by bioactive compounds in EFA and EFB could be another promising therapeutic agent in reducing the cholesterol levels and atherosclerosis by targeting PCSK9.

Beneficial effects of PCSK9 inhibition with alirocumab in familial hypercholesterolemia involve modulation of new immune players

Familial hypercholesterolemia (FH) is associated with low-grade systemic inflammation, a key driver of premature atherosclerosis. We investigated the effects of inhibiting proprotein convertase subtilisin/kexin type 9 (PCSK9) function on inflammatory state, endothelial dysfunction and cardiovascular outcomes in patients with FH. Fourteen patients with FH were evaluated before and 8 weeks after administration of a PCSK9 blocking monoclonal antibody (alirocumab, 150 mg/subcutaneous/14 days). In vivo and ex vivo analysis revealed that alirocumab blunted the attachment of leukocytes to TNFα-stimulated human umbilical arterial endothelial cells (HUAEC) and suppressed the activation of platelets and most leukocyte subsets, which was accompanied by the diminished expression of CX₃CR1, CXCR6 and CCR2 on several leukocyte subpopulations. By contrast, T-regulatory cell activation was enhanced by alirocumab treatment, which also elevated anti-inflammatory IL-10 plasma levels and lowered circulating pro-inflammatory cytokines. Plasma levels of IFNγ positively correlated with levels of total and LDL-cholesterol, whereas circulating IL-10 levels negatively correlated with these key lipid parameters. In vitro analysis revealed that TNFα stimulation of HUAEC increased the expression of PCSK9, whereas endothelial PCSK9 silencing reduced TNFα-induced mononuclear cell adhesion mediated by Nox5 up-regulation and p38-MAPK/NFκB activation, concomitant with reduced SREBP2 expression. PCSK9 silencing also decreased endothelial CX₃CL1 and CXCL16 expression and chemokine generation. In conclusion, PCSK9 inhibition impairs systemic inflammation and endothelial dysfunction by constraining leukocyte-endothelium interactions. PCSK9 blockade may constitute a new therapeutic approach to control the inflammatory state associated with FH, preventing further cardiovascular events in this cardiometabolic disorder.

Neutrophil-to-hepatocyte communication via LDLR-dependent miR-223-enriched extracellular vesicle transfer ameliorates nonalcoholic steatohepatitis

Neutrophil infiltration around lipotoxic hepatocytes is a hallmark of nonalcoholic steatohepatitis (NASH); however, how these 2 types of cells communicate remains obscure. We have previously demonstrated that neutrophil-specific microRNA-223 (miR-223) is elevated in hepatocytes to limit NASH progression in obese mice. Here, we demonstrated that this elevation of miR-223 in hepatocytes was due to preferential uptake of miR-223-enriched extracellular vesicles (EVs) derived from neutrophils as well other types of cells, albeit to a lesser extent. This selective uptake was dependent on the expression of low-density lipoprotein receptor (LDLR) on hepatocytes and apolipoprotein E (APOE) on neutrophil-derived EVs, which was enhanced by free fatty acids. Once internalized by hepatocytes, the EV-derived miR-223 acted to inhibit hepatic inflammatory and fibrogenic gene expression. In the absence of this LDLR- and APOE-dependent uptake of miR-223-enriched EVs, the progression of steatosis to NASH was accelerated. In contrast, augmentation of this transfer by treatment with an inhibitor of proprotein convertase subtilisin/kexin type 9, a drug used to lower blood cholesterol by upregulating LDLR, ameliorated NASH in mice. This specific role of LDLR and APOE in the selective control of miR-223-enriched EV transfer from neutrophils to hepatocytes may serve as a potential therapeutic target for NASH.

Plasma Purification Treatment Relieves the Damage of Hyperlipidemia to PBMCs

Background: Hyperlipidemia {hypercholesterolemia [cholesterol >5.18 mmol/L) or hypertriglyceridemia [triglycerides >2.3 mmol/L], mixed hyperlipidemia [cholesterol >5.18 mmol/L and triglycerides >2.3 mmol/L], and high low-density lipoproteinemia [low-density lipoprotein (LDL) >3.4 mmol/L]} is a strong risk factor for arteriosclerosis and cardiovascular disease (CVD). Therapy with lipid-lowering drugs often results in many side effects. Our study aimed to investigate the potential effects of non-drug therapy with double-filtration plasmapheresis (DFPP) on lipid metabolism-, endoplasmic reticulum (ER) stress-, and apoptosis-related proteins in peripheral blood mononuclear cells (PBMCs) before and after lipid clearance in patients with hyperlipidemia.

Methods: Thirty-five hyperlipidemia patients were selected. Proteins related to lipid metabolism [CD36, proprotein convertase subtilisin/kexin type 9 (PCSK9), and LDL receptor], ER stress [glucose-regulated protein 78 (Grp78), C/EBP homologous protein (CHOP), activating transcription factor 4 (ATF4), and eukaryotic initiation factor 2α (EIF2α)], and apoptosis [B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (BAX), and cysteinyl aspartate specific proteinase-3 (Caspase-3)] were assayed by Western blot, reactive oxygen species (ROS) were measured by flow cytometry (FCM), and ELISA detected serum inflammatory [interleukin (IL)-1β, IL-6, and tumor necrosis factor α (TNF-α)] factors.

Results: Compared with their pre-DFPP values, the values of most lipid metabolic parameters, such as cholesterol, triglycerides, LDL, lipoprotein a [Lp(a)], and small dense LDL (sdLDL) cholesterol, were reduced after DFPP. DFPP was associated with the downregulation of proteins related to lipid metabolism, ER stress, and apoptosis, resulting in decreased ROS and serum inflammatory factor release.

Conclusion: DFPP has lipid-lowering activity and can also regulate lipid metabolism-, ER stress-, and apoptosis-related proteins in PBMCs and reduce the levels of inflammatory factors in patients with hyperlipidemia (ClinicalTrials.gov number: NCT03491956).

Lipid lowering with bempedoic acid added to a proprotein convertase subtilisin/kexin type 9 inhibitor therapy: A randomized, controlled trial

BACKGROUND

Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9is) lower low-density lipoprotein cholesterol (LDL-C) in patients with hypercholesterolemia. However, some patients receiving PCSK9i therapy might require additional lipid-lowering therapy (LLT) to reach LDL-C goals. Bempedoic acid is an oral, once-daily, ATP-citrate lyase inhibitor that significantly lowers LDL-C in patients with hypercholesterolemia when given alone or as add-on therapy to statins and/or ezetimibe.

OBJECTIVE

Assess safety and efficacy of bempedoic acid added to PCSK9i (evolocumab) background therapy in patients with hypercholesterolemia.

METHODS

This phase 2, randomized, double-blind, placebo-controlled study was conducted in three phases: 1.5-month screening/washout period including discontinuation of all LLTs, a 3-month period wherein patients initiated background PCSK9i therapy, and a 2-month treatment period in which patients were randomized 1:1 to receive bempedoic acid 180 mg or placebo once daily while continuing PCSK9i therapy.

RESULTS

Of 59 patients randomized, 57 completed the study. Mean baseline LDL-C after 3 months of PCSK9i background therapy was 103.1 ± ± 30.4 mg/dL. Bempedoic acid added to background PCSK9i therapy significantly lowered LDL-C by 30.3% (P < .001) vs placebo. Compared with placebo, bempedoic acid significantly lowered apolipoprotein B, non-high-density lipoprotein cholesterol, and total cholesterol (nominal P < .001 for all), and high-sensitivity C-reactive protein (P = .029). When added to background PCSK9i therapy, the safety profile of bempedoic acid was comparable to that observed for placebo.

CONCLUSIONS

When added to a background of PCSK9i therapy, bempedoic acid significantly lowered LDL-C levels with a safety profile comparable to placebo in patients with hypercholesterolemia.

Real-World Efficacy of Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitors (PCSK9i) in Heterozygous Familial Hypercholesterolemia Patients Referred for Lipoprotein Apheresis

BACKGROUND A small proportion of familial hypercholesterolemia (FH) patients can adequately control this condition, although achieving the recommended targets for low-density lipoprotein cholesterol (LDL-c) levels remains a challenge. Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) are new and potent lipid-lowering drugs. However, there is scarce literature on real-world data about their use in patients with FH. MATERIAL AND METHODS We examined the reduction in LDL-c levels from the baseline, after PCSK9i initiation in heterozygous familial hypercholesterolemia patients referred for lipoprotein apheresis in our regional lipid clinic. The study was conducted from March 2018 to September 2019, the period immediately after PCSK9i reimbursement was available in France. PCSK9i was added on top of the patients' maximal tolerated lipid-lowering regimens. RESULTS The study had 123 patients with heterozygous FH. The mean age of the patients was 59±11 years. The mean baseline LDL-c for all the participants was 277±78 mg/dl. It was 283±81 mg/dl in the PCSK9i monotherapy group (n=83), 247±68 mg/dl in the PCSK9i plus ezetimibe group (n=12), and 264±78 mg/dl in the PCSK9i plus statin and ezetimibe group (n=28). The mean decrease observed in the LDL-c level from baseline was 136±70 mg/dl (n=123), 125±60 mg/dl (n=83), 103±77 mg/dl (n=12), and 175±70 mg/dl (n=28), respectively. CONCLUSIONS An overall reduction of 49.1% from the baseline LDL-c was observed in the heterozygous FH population after PCSK9i initiation in a real-world experience. The group treated with PCSK9i ezetimibe plus statin showed further reduction of their LDL-c levels with a better responder rate, achieving the target 50% reduction in LDL-c from the baseline.

The role of proprotein convertase subtilisin/kexin type-9 concentration and paraoxonase 1 activities in the blood of women with polycystic ovary syndrome

This study aimed to evaluate the concentration of proprotein convertase subtilisin/kexin type-9 (PCSK9) and the activities of paraoxonase 1 in women with and without polycystic ovary syndrome (PCOS). We found significant higher PCSK9, whereas lower high-density lipoprotein concentration in the serum of women with PCOS when compared to the group without PCOS. Also paraoxonase 1 activities were significantly different between women with PCOS than without PCOS. In addition, the women with PCOS and insulin resistance had higher concentrations of PCSK9 than women with PCOS and insulin sensitivity. Higher PCSK9 concentration in the group with PCOS could be also associated with hormones concentrations. Changes in paraoxonase 1 activities and lipid profile parameters as well as higher concentration of PCSK9 in the group of women with PCOS could be associated with metabolism disorders, but due to the small clinical sample size, the study should be continued.

Screening of PCSK9 and LDLR genetic variants in Familial Hypercholesterolemia (FH) patients in India

Familial Hypercholesterolemia (FH) is an autosomal, dominant, inherited disorder characterized by severely elevated LDL-cholesterol (LDL-C) levels with high risk for Coronary Artery Disease (CAD). There are limited genetic studies especially on genes other than Low Density Lipoprotein receptor (LDLR) conducted in Indian population. Thus, our aim was to screen the entire Proprotein Convertase Subtilisin/Kexin type 9 gene (PCSK9) gene & hotspot exons 3, 4 and 9 of LDLR gene in FH cases and controls. 50 FH cases were categorized into definite, probable and possible cases according to Dutch Lipid Network Criteria (DLNC) who were gender matched with 50 healthy controls. All 12 exons of PCSK9, and hotspot exons 3, 4 & 9 of LDLR gene were screened through High Resolution Melt (HRM) curve analysis. Enzyme linked immunosorbent assay was performed to measure circulating PCSK9 levels. Total cholesterol and LDL-C were significantly high in all three groups of cases. Total 8 nonpathogenic variants in exon 1, 5, 7 and 9 of the PCSK9 gene were detected. In LDLR gene, 3 known pathogenic and 1 benign variant were found in exon 3 & 4. In FH cases, PCSK9 levels were significantly high compared to controls (P = 0.0001), and were directly correlated to LDL-C (P = 0.0001) and Total Cholesterol (P = 0.0001). Our study is first to screen the entire PCSK9 gene in western part of India. Since no pathogenic variants were identified, it is possible that PCSK9 variants are clinically less relevant. However, 3 known pathogenic variants were found in the LDLR gene. These findings support our understanding of the genetic spectrum of FH in India.

Rapid Decline of Serum Proprotein Convertase Subtilisin/Kexin 9 (PCSK9) in Non-Cirrhotic Patients with Chronic Hepatitis C Infection Receiving Direct-Acting Antiviral Therapy

Direct-acting antivirals (DAAs) efficiently eradicate the hepatitis C virus (HCV). Low-density lipoprotein (LDL) levels increase rapidly upon DAA treatment. Proprotein convertase subtilisin/kexin 9 (PCSK9) induces degradation of the hepatic LDL receptor and thereby elevates serum LDL. The aim of this study was to determine serum PCSK9 concentrations during and after DAA therapy to identify associations with LDL levels. Serum PCSK9 was increased in 82 chronic HCV-infected patients compared to 55 patients not infected with HCV. Serum PCSK9 was low in HCV patients with liver cirrhosis, but patients with HCV-induced liver cirrhosis still exhibited higher serum PCSK9 than patients with non-viral liver cirrhosis. Serum PCSK9 correlated with measures of liver injury and inflammation in cirrhotic HCV patients. In patients without liver cirrhosis, a positive association of serum PCSK9 with viral load existed. Serum PCSK9 was not different between viral genotypes. Serum PCSK9 did not correlate with LDL levels in HCV patients irrespective of cirrhotic status. Serum PCSK9 was reduced, and LDL was increased at four weeks after DAA therapy start in non-cirrhotic HCV patients. Serum PCSK9 and LDL did not change upon DAA treatment in the cirrhotic group. The rapid decline of PCSK9 after the start of DAA therapy in conjunction with raised LDL levels in non-cirrhotic HCV patients shows that these changes are not functionally related.

Umbrella Review on Non-Statin Lipid-Lowering Therapy

OBJECTIVES

The main aim of this review was to summarize current evidence on approved and emerging non-statin lipid-lowering therapies.

METHODS AND MATERIALS

Recent literature on U.S. FDA approved non-statin lipid-lowering therapies and evolving lipid-lowering drugs currently under development was reviewed.

RESULTS AND DISCUSSION

In the past 20 years, the emergence of non-statin cholesterol-lowering drugs has changed the landscape of dyslipidemia management. Food and Drug Administration approval of non-statin lipid-lowering therapies such as ezetimibe, proprotein convertase subtilisin/Kexin type 9 (PCSK9) inhibitors (evolocumab, alirocumab), bempedoic acid and combination of bempedoic acid and ezetimibe, evinacumab and other triglyceride-lowering agents (eg, icosapent ethyl) has emerged. The European Commission has also recently approved inclisiran for treatment of hypercholesterolemia and mixed hypercholesterolemia even though FDA has put the approval of this drug on hold. Recent guidelines have incorporated PCSK9 inhibitors to treat patients with primary hyperlipidemia and patients with very high-risk ASCVD, who could not achieve adequate lipid-lowering with combination therapy of maximally tolerated statin and ezetimibe. Icosapent ethyl use as an adjunct therapy to statins is also recommended to reduce the risk of ASCVD in patients with hypertriglyceridemia.

CONCLUSION

Despite cost limitations, the uptake of PCSK9 inhibitors is increasing. Approval of bempedoic acid alone or in combination with ezetimibe has provided additional oral lipid-lowering drug alternatives to ezetimibe. Various lipid-lowering drug targets are under investigation.

Circulating levels of proprotein convertase subtilisin/kexin type 9 (PCSK9) are associated with monocyte subsets in patients with stable coronary artery disease

BACKGROUND

Proprotein convertase subtilisin/kexin type-9 (PCSK9) is an enzyme promoting the degradation of low-density lipoprotein receptors (LDL-R) in hepatocytes. Inhibition of PCSK9 has emerged as a novel target for lipid-lowering therapy. Monocytes are crucially involved in the pathogenesis of atherosclerosis and can be divided into three subsets.

OBJECTIVE

The aim of this study was to examine whether circulating levels of PCSK9 are associated with monocyte subsets.

METHODS

We included 69 patients with stable coronary artery disease. PCSK9 levels were measured and monocyte subsets were assessed by flow cytometry and divided into classical monocytes (CD14++CD16-; CM), intermediate monocytes (CD14++CD16+; IM) and non-classical monocytes (CD14+CD16++; NCM).

RESULTS

Mean age was 64 years and 80% of patients were male. Patients on statin treatment (n = 55) showed higher PCSK9-levels (245.4 (206.0-305.5) ng/mL) as opposed to those without statin treatment (186.1 (162.3-275.4) ng/mL; p = 0.05). In patients on statin treatment, CM correlated with circulating PCSK9 levels (R = 0.29; p = 0.04), while NCM showed an inverse correlation with PCSK9 levels (R = -0.33; p = 0.02). Patients with PCSK9 levels above the median showed a significantly higher proportion of CM as compared to patients with PCSK9 below the median (83.5 IQR 79.2-86.7 vs. 80.4, IQR 76.5-85.2%; p = 0.05). Conversely, PCSK9 levels >median were associated with a significantly lower proportion of NCM as compared to those with PCSK9 <median (10.2, IQR 7.3-14.6 vs. 14.3, IQR 10.9-18.7%; p = 0.02). In contrast, IM showed no association with PCSK9 levels.

CONCLUSIONS

We hereby provide a novel link between PCSK9 regulation, innate immunity and atherosclerotic disease in statin-treated patients.

Supplementation with Octacosanol Affects the Level of PCSK9 and Restore Its Physiologic Relation with LDL-C in Patients on Chronic Statin Therapy

Dietary supplementation with sugar cane derivates may modulate low-density lipoprotein cholesterol (LDL-C) and proprotein convertase subtilisin/kexin type 9 (PCSK9) levels. The purpose of this study was to determine if dietary supplement (DS), containing Octacosanol (20 mg) and vitamin K2 (45 µg), could restore the disrupted physiologic relation between LDL-C and serum PCSK9. Double-blind, randomized, placebo-controlled, single-center study including 87 patients on chronic atorvastatin therapy was conducted. Eighty-seven patients were randomized to receive DS (n = 42) or placebo (n = 45), and followed for 13 weeks. Serum PCSK9 levels, lipid parameters and their relationship were the main efficacy endpoints. The absolute levels of PCSK9 and LDL-C were not significantly different from baseline to 13 weeks. However, physiologic correlation between % change of PCSK9 and % change of LDL-C levels was normalized only in the group of patients treated with DS (r = 0.409, p = 0.012). This study shows that DS can restore statin disrupted physiologic positive correlation between PCSK9 and LDL-C. Elevated PCSK9 level is an independent risk factor so controlling its rise by statins may be important in prevention of cardiovascular events.

U.S. FDA Approved Drugs from 2015-June 2020: A Perspective

In the present work, we report compilation and analysis of 245 drugs, including small and macromolecules approved by the U.S. FDA from 2015 until June 2020. Nearly 29% of the drugs were approved for the treatment of various types of cancers. Other major therapeutic areas of focus were infectious diseases (14%); neurological conditions (12%); and genetic, metabolic, and cardiovascular disorders (7-8% each). Itemization of the approved drugs according to the year of approval, sponsor, target, chemical class, major drug-metabolizing enzyme(s), route of administration/elimination, and drug-drug interaction liability (perpetrator or/and victim) is presented and discussed. An effort has been made to analyze the pharmacophores to identify the structural (e.g., aromatic, heterocycle, and aliphatic), elemental (e.g., boron, sulfur, fluorine, phosphorus, and deuterium), and functional group (e.g., nitro drugs) diversity among the approved drugs. Further, descriptor-based chemical space analysis of FDA approved drugs and several strategies utilized for optimizing metabolism leading to their discoveries have been emphasized. Finally, an analysis of drug-likeness for the approved drugs is presented.

Proprotein convertase subtilisin/kexin type 9 is related to disease activity and damage in patients with systemic erythematosus lupus

Background:

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a serine protease that regulates cholesterol metabolism through low-density lipoprotein receptor degradation and that has been linked to cardiovascular (CV) disease. The purpose of the present study was to examine whether PCSK9 levels are disrupted compared with controls in patients with systemic lupus erythematosus (SLE). We additionally sought to establish whether PCSK9 is related to both the abnormalities in the lipid profile and to the disease activity or damage of patients with SLE.

Methods:

We performed a cross-sectional study that encompassed 366 individuals: 195 SLE patients and 171 age-, sex-, and statin intake-matched controls. PCSK9, lipoproteins serum concentrations, and lipid profiles were assessed in patients and controls. A multivariable analysis, adjusted for standard CV risk factors, was performed to evaluate the role of PCSK9 in SLE-related dyslipidemia.

Results:

Most lipid related-molecules were decreased in patients with SLE compared with controls. This downregulation included PCSK9, with PCSK9 levels being lower in patients than controls in the full multivariable analysis, including the modifications in lipid profiles that the disease itself produces {beta coefficient –73 [95% confidence interval (CI) –91 to –54] ng/ml, p ⩽ 0.001}. Both SLICC and SLEDAI scores were independently and positively related to PCSK9. Patients currently on hydroxychloroquine exhibited decreased levels of PCSK9 compared with those that were not taking hydroxychloroquine [beta coefficient –30 (95% CI −54 to −6) ng/ml, p = 0.015].

Conclusion:

PCSK9 is downregulated in SLE compared with controls, but SLE patients with higher disease activity and damage exhibited higher PSCK9 serum levels.

The Effect of Low-Fat and Low-Carbohydrate Diets on Weight Loss and Lipid Levels: A Systematic Review and Meta-Analysis

BACKGROUND

The rise in obesity has emphasised a focus on lifestyle and dietary habits. We aimed to address the debate between low-carbohydrate and low-fat diets and compare their effects on body weight, low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), total cholesterol, and triglycerides in an adult population.

METHOD

Medline and Web of Science were searched for randomised controlled trials (RCTs) comparing low-fat and low-carbohydrate diets up to September 2019. Three independent reviewers extracted data. Risk of bias was assessed using the Cochrane tool. The meta-analysis was stratified by follow-up time using the random-effects models.

RESULTS

This meta-analysis of 38 studies assessed a total of 6499 adults. At 6-12 months, pooled analyses of mean differences of low-carbohydrate vs. low-fat diets favoured the low-carbohydrate diet for average weight change (mean difference -1.30 kg; 95% CI -2.02 to -0.57), HDL (0.05 mmol/L; 95% CI 0.03 to 0.08), and triglycerides (TG) (-0.10 mmol/L; -0.16 to -0.04), and favoured the low-fat diet for LDL (0.07 mmol/L; 95% CI 0.02 to 0.12) and total cholesterol (0.10 mmol/L; 95% CI 0.02 to 0.18). Conclusion and Relevance: This meta-analysis suggests that low-carbohydrate diets are effective at improving weight loss, HDL and TG lipid profiles. However, this must be balanced with potential consequences of raised LDL and total cholesterol in the long-term.

The scientific basis of rational prescribing. A guide to precision clinical pharmacology based on the WHO 6-step method

Background and methods

This opinion paper expanded on the WHO “six-step approach to optimal pharmacotherapy,” by detailed exploration of the underlying pharmacological and pathophysiological principles. This exercise led to the identification of a large number of domains of research that should be addressed to make clinical pharmacology progress toward “precision clinical pharmacology,” as a prerequisite for precision medicine.

Result

In order to improve clinical efficacy and safety in patient groups (to guide drug development) as well as in individuals (to guide therapeutic options and optimize clinical outcome), developments in clinical pharmacology should at least tackle the following: (1) molecular diagnostic assays to guide drug design and development and allow physicians to identify the optimal targets for therapy in the individual patient in a quick and precise manner (to guide selection of the right drug for the right patient); (2) the setting up and validation of biomarkers of target engagement and modification as predictors of clinical efficacy and safety; (3) integration of physiological PK/PD models and intermediate markers of pharmacological effects with the natural evolution of the disease to predict the drug dose that most effectively improves clinical outcome in patient groups and individuals, making use of advanced modeling technologies (building on deterministic models, machine-learning, and deep learning algorithms); (4) methodology to validate human or humanized in vitro, ex vivo, and in vivo models for their ability to predict clinical outcome with investigational therapies, including nucleic acids or recombinant genes together with vectors (including viruses or nanoparticles), cell therapy, or therapeutic vaccines; (5) methodological complements to the gold-standard, large Phase 3 randomized clinical trial to provide clinically relevant and reliable data on the efficacy and safety of all treatment options at the population level (pragmatic clinical trials), as well as in small groups of patients (as low as n = 1); (6) regulatory science, so as to optimize the ethical review process, documentation, and monitoring of clinical trials, improve efficiency, and reduce costs of clinical drug development; (7) interventions to effectively improve patient compliance and to rationalize polypharmacy for the reduction of adverse effects and the enhancement of therapeutic interactions; and (8) appraisal of the ecological and societal impact of drug use to safeguard against environmental hazards (following the “One Health” concept) and to reduce drug resistance.

Discussion and conclusion

As can be seen, precision clinical pharmacology aims at being highly translational, which will require very large panels of complementary skills. Interdisciplinary collaborations, including non-clinical pharmacologists, will be key to achieve such an ambitious program.

Relation of Proprotein Convertase Subtilisin/Kexin Type 9 to Cardiovascular Outcomes in Patients Undergoing Percutaneous Coronary Intervention

The pharmacological inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9) has been shown to drastically affect low-density lipoprotein cholesterol levels and associated cardiovascular diseases. However, the potential effectiveness of PCSK9 serum levels as a biomarker for cardiovascular risk remains unclear. Serum PCSK9 levels in patients who underwent percutaneous coronary intervention (PCI) may predict long-term outcomes. PCSK9 levels were measured in 749 consecutive patients with coronary artery disease undergoing PCI. These patients were classified into 2 groups according to their serum levels of PCSK9. The primary end point was a composite of the major adverse cardiac events (MACE), including cardiac death, myocardial infarction, stroke, and any revascularization. The median PCSK9 level was 302.82 ng/ml. During a median follow-up of 28.4 months, a total of 38 (5.1%) MACE was recorded, and 50 (6.7%) patients died from any cause. Multivariate Cox regression analysis showed that compared with a lower serum PCSK9 level, a higher serum PCSK9 level was independently associated with a higher rate of MACE (adjusted hazard ratio 2.290, 95% confidence interval 1.040 to 5.045, p = 0.040) and all-cause death (adjusted hazard ratio 2.511, 95% confidence interval 1.220 to 5.167, p = 0.026). Results were consistent after propensity-score matching (MACE, adjusted HR 2.236, 95% CI 1.011-5.350, p = 0.047; all-cause death, adjusted HR 2.826, 95% CI 1.258-6.349, p = 0.012). Baseline serum PCSK9 levels were associated with long-term cardiovascular clinical outcomes and mortality during the long-term follow-up after PCI in patients with coronary artery disease.

Monocyte Chemoattractant Protein-1 Is an Independent Predictor of Coronary Artery Ectasia in Patients with Acute Coronary Syndrome

Our purpose was to assess a possible association of inflammatory, lipid and mineral metabolism biomarkers with coronary artery ectasia (CAE) and to determine a possible association of this with acute atherotrombotic events (AAT). We studied 270 patients who underwent coronary angiography during an acute coronary syndrome 6 months before. Plasma levels of several biomarkers were assessed, and patients were followed during a median of 5.35 (3.88–6.65) years. Two interventional cardiologists reviewed the coronary angiograms, diagnosing CAE according to previously published criteria in 23 patients (8.5%). Multivariate binary logistic regression analysis was used to search for independent predictors of CAE. Multivariate analysis revealed that, aside from gender and a diagnosis of dyslipidemia, only monocyte chemoattractant protein-1 (MCP-1) (OR = 2.25, 95%CI = (1.35–3.76) for each increase of 100 pg/mL, p = 0.001) was independent predictor of CAE, whereas mineral metabolism markers or proprotein convertase subtilisin/kexin type 9 were not. Moreover, CAE was a strong predictor of AAT during follow-up after adjustment for other clinically relevant variables (HR = 2.67, 95%CI = (1.22–5.82), p = 0.013). This is the first report showing that MCP-1 is an independent predictor of CAE, suggesting that CAE and coronary artery disease may share pathogenic mechanisms. Furthermore, CAE was associated with an increased incidence of AAT.