Bezafibrate Infarction Prevention (BIP) study. Secondary prevention by raising HDL cholesterol and reducing triglycerides in patients with coronary artery disease

Pleiotropic Effects of Peroxisome Proliferator-Activated Receptor Alpha and Gamma Agonists on Myocardial Damage: Molecular Mechanisms and Clinical Evidence-A Narrative Review

Cardiovascular diseases remain the leading cause of death in the world, and that is why finding an effective and multi-functional treatment alternative to combat these diseases has become more important. Fibrates and thiazolidinediones, peroxisome proliferator-activated receptors alpha and gamma are the pharmacological therapies used to treat dyslipidemia and type 2 diabetes, respectively. New mechanisms of action of these drugs have been found, demonstrating their pleiotropic effects, which contribute to preserving the heart by reducing or even preventing myocardial damage. Here, we review the mechanisms underlying the cardioprotective effects of PPAR agonists and regulating morphological and physiological heart alterations (metabolic flexibility, mitochondrial damage, apoptosis, structural remodeling, and inflammation). Moreover, clinical evidence regarding the cardioprotective effect of PPAR agonists is also addressed.

Managing hypertriglyceridemia for cardiovascular disease prevention: Lessons from the PROMINENT trial

BACKGROUND

Numerous epidemiological studies have shown that hypertriglyceridemia is a significant risk factor for cardiovascular diseases (CVD). However, large clinical studies on triglyceride-lowering therapy have yielded inconsistent results. In the current review, we reassess the importance of triglyceride-lowering therapy in preventing CVD based on previous literature and the recently published findings of the PROMINENT trial.

METHODS

This narrative review is based on literature and public documents published up to November 2023.

RESULTS

Meta-analyses of trials on peroxisome proliferator-activated receptor α agonists and triglyceride-lowering therapy, including the PROMINENT trial, have indicated that triglyceride-lowering therapy can reduce CVD events. Mendelian randomization studies have also indicated that triglyceride is indeed a true risk factor for coronary artery disease, leaving no doubt about its relationship to CVD. Meanwhile, the negative results from the PROMINENT trial were likely due to the insufficient triglyceride-lowering effect, slight increases in low-density lipoprotein cholesterol and apolipoprotein B, and the inclusion of mostly high-intensity statin users as target patients. It is unlikely that adverse events counteracted the effectiveness of pemafibrate on outcomes. Additionally, pemafibrate has shown positive effects on non-alcoholic fatty liver disease and peripheral artery disease.

CONCLUSION

Although the PROMINENT trial did not demonstrate the significance of pemafibrate as a triglyceride-lowering therapy in a specific population, it does not necessarily negate the potential benefits of treating hypertriglyceridemia in reducing CVD events. It is necessary to explore appropriate populations that could benefit from this therapy, utilize data from the PROMINENT trial and other databases, and validate findings in real-world settings.

Beyond LDL-C: unravelling the residual atherosclerotic cardiovascular disease risk landscape-focus on hypertriglyceridaemia

Aims

Historically, atherosclerotic cardiovascular disease (ASCVD) risk profile mitigation has had a predominant focus on low density lipoprotein cholesterol (LDL-C). In this narrative review we explore the residual ASCVD risk profile beyond LDL-C with a focus on hypertriglyceridaemia, recent clinical trials of therapeutics targeting hypertriglyceridaemia and novel modalities addressing other residual ASCVD risk factors.

Findings

Hypertriglyceridaemia remains a significant ASCVD risk despite low LDL-C in statin or proprotein convertase subtilisin/kexin type 9 inhibitor-treated patients. Large population-based observational studies have consistently demonstrated an association between hypertriglyceridaemia with ASCVD. This relationship is complicated by the co-existence of low high-density lipoprotein cholesterol. Despite significantly improving atherogenic dyslipidaemia, the most recent clinical trial outcome has cast doubt on the utility of pharmacologically lowering triglyceride concentrations using fibrates. On the other hand, purified eicosapentaenoic acid (EPA), but not in combination with docosahexaenoic acid (DHA), has produced favourable ASCVD outcomes. The outcome of these trials suggests alternate pathways involved in ASCVD risk modulation. Several other pharmacotherapies have been proposed to address other ASCVD risk factors targeting inflammation, thrombotic and metabolic factors.

Implications

Hypertriglyceridaemia poses a significant residual ASCVD risk in patients already on LDL-C lowering therapy. Results from pharmacologically lowering triglyceride are conflicting. The role of fibrates and combination of EPA and DHA is under question but there is now convincing evidence of ASCVD risk reduction with pure EPA in a subgroup of patients with hypertriglyceridaemia. Clinical guidelines should be updated in line with recent clinical trials evidence. Novel agents targeting non-conventional ASCVD risks need further evaluation.

Remnant cholesterol and the risk of diabetic nephropathy progression to end-stage kidney disease in patients with type 2 diabetes mellitus: a longitudinal cohort study

AIM

Diabetic nephropathy (DN) is the most common cause of end-stage kidney disease (ESKD). Remnant cholesterol has been investigated as a predictor for the progression of DN in type 1 diabetes mellitus patients, as well as the incidence of DN in type 2 diabetes mellitus (T2DM) patients. This study aimed to evaluate the longitudinal relationship between baseline remnant cholesterol and kidney outcomes using a Chinese T2DM with biopsy-confirmed DN cohort.

METHODS

We included 334 patients with T2DM and biopsy-confirmed DN during 2010-2019 West China Hospital T2DM-DN cohort. Remnant cholesterol was defined by Martin-Hopkins equation. Patients were divided into four groups based on the median (IQR) remnant cholesterol concentration at the time of renal biopsy. The kidney outcome was defined as ESKD, which was defined as the need for chronic kidney replacement therapy or estimated glomerular filtration rate (eGFR) < 15 mL/min/1.73 m2. The relationship between remnant cholesterol and kidney outcome was analyzed using the Kaplan‒Meier method and Cox regression analysis.

RESULTS

The mean age was 51.1 years, and 235 (70%) were men. During follow-up, a total of 121 (36.2%) patients reached ESKD. The Kaplan‒Meier analysis showed that patients in the highest quartile (quartile 4) group had lower cumulative renal survival (log-rank test, p = 0.033) and shorter median renal survival time [34.0 (26.4-41.6) vs. 55.0 (29.8-80.2) months] than patients in the lowest quartile (quartile 1) group. By univariate analysis, the high remnant cholesterol group was associated with a higher risk of progression to ESKD. Moreover, the risk of progression to ESKD in the highest quartile was still 2.857-fold (95% CI 1.305-6.257, p = 0.009) higher than that in the lowest quartile, and one-SD increase of remnant cholesterol was associated with a higher risk (HR = 1.424; 95% CI 1.075-1.886, p = 0.014) of progression to ESKD, after adjusted for confounding factors.

CONCLUSIONS

High remnant cholesterol is independently associated with a higher risk of ESKD in patients with T2DM-DN, and it may be a new noninvasive marker of ESKD.

CLINICAL RELEVANCE

Calculated remnant cholesterol has the advantages of being economical and clinically accessible. Moreover, to our knowledge, there are no longitudinal cohort studies for investigating the risk of progression of T2DM-DN to ESKD. In our study, higher remnant cholesterol was associated with a higher risk of ESKD in patients with T2DM-DN, and it may be a new noninvasive predictor of ESKD.

Addressing residual risk beyond statin therapy: New targets in the management of dyslipidaemias-A report from the European Society of Cardiology Cardiovascular Round Table

Cardiovascular (CV) disease is the most common cause of death in Europe. Despite proven benefits, use of lipid-lowering therapy remains suboptimal. Treatment goals are often not achieved, even in patients at high risk with atherosclerotic CV disease (ASCVD). The occurrence of CV events in patients on lipid-lowering drugs is defined as "residual risk", and can result from inadequate control of plasma lipids or blood pressure, inflammation, diabetes, and environmental hazards. Assessment of CV risk factors and vascular imaging can aid in the evaluation and management decisions for individual patients. Lifestyle measures remain the primary intervention for lowering CV risk. Where drug therapies are required to reach lipid treatment targets, their effectiveness increases when they are combined with lifestyle measures delivered through formal programs. However, lipid drug dosage and poor adherence to treatment remain major obstacles to event-free survival. This article discusses guideline-supported treatment algorithms beyond statin therapy that can help reduce residual risk in specific patient profiles while also likely resulting in substantial healthcare savings through better patient management and treatment adherence.

Triglyceride-lowering therapy for the prevention of cardiovascular events, stroke, and mortality in patients with diabetes: A meta-analysis of randomized controlled trials

BACKGROUND AND AIMS

Triglyceride (TG)-lowering therapy is efficient for the prevention of cardiovascular disease (CVD) in the general population; however, for diabetic individuals, it is more controversial. The purpose of this study was to pool the results from randomized controlled trials (RCTs) to clarify whether the lowering of TG is beneficial for the prevention of CVD events, stroke, and mortality in subjects with diabetes.

METHODS

MEDLINE, Web of Science, EMBASE, ClinicalTrials.gov, and the Cochrane Central Register for Controlled Trials were searched to identify the relevant literature. We included randomized controlled trials (RCTs) to assess the association of triglyceride-lowering therapy with the prevention of CVD events, stroke, and mortality in diabetic patients.

RESULTS

Overall, 19 studies were included in this meta-analysis. Compared with the control groups, TG lowering was associated with a decreased risk of CVD events (RR = 0.91, 95% CI 0.87-0.95, p = 0.000) and CVD mortality (RR = 0.93, 95% CI 0.86-1.00, p = 0.047). There was no significant correlation between TG-lowering therapy and the incidence of stroke and all-cause mortality (RR = 0.93, 95% CI 0.86-1.02, p = 0.129 and RR = 0.97, 95% CI 0.93-1.01, p = 0.107, respectively). Subgroup analysis showed that the decreased CVD risk resulting from TG-lowering therapy was independent of age, sex, region, duration of follow-up, degree of TG reduction and glycemic control.

CONCLUSIONS

TG-lowering therapy is associated with a reduction in CVD events and cardiovascular-specific mortality, but not in stroke and all-cause mortality. Future large, multicenter RCTs will further confirm these conclusions.

New Insights Into the Treatment of Hyperlipidemia: Pharmacological Updates and Emerging Treatments

Cardiovascular diseases are the leading causes of global mortality and morbidity. Hyperlipidemia is a significant risk factor for atherosclerosis and subsequent cardiovascular diseases. Hyperlipidemia is characterized by imbalances in blood cholesterol levels, particularly elevated low-density lipoprotein cholesterol and triglycerides, and is influenced by genetic and environmental factors. Current management consists of lifestyle modifications and pharmacological interventions most commonly consisting of statins. This review paper explores pathophysiology, management strategies, and pharmacotherapies including commonly used well-established medications including statins, fibrates, and ezetimibe, exciting novel therapies including proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, and RNA interference therapies (inclisiran), lomitapide, and bempedoic acid, highlighting their mechanisms of action, clinical efficacy, and safety profiles. Additionally, emerging therapies under clinical trials including ApoC-III inhibitors, DGAT2 inhibitors, ACAT2 Inhibitors, and LPL gene therapies are examined for their potential to improve lipid homeostasis and cardiovascular outcomes. The evolving landscape of hyperlipidemia management underscores the importance of continued research into both established therapies and promising new candidates, offering hope for more effective treatment strategies in the future.

Remnant cholesterol, LDL cholesterol, and apoB absolute mass changes explain results of the PROMINENT trial

BACKGROUND AND AIMS

The PROMINENT trial, a cardiovascular outcome trial of the triglyceride- and remnant cholesterol-lowering agent pemafibrate, has shown neutral results despite reduction in plasma triglycerides and remnant cholesterol. We tested the hypothesis that absolute mass changes in remnant cholesterol, LDL cholesterol, and apolipoprotein B explain the results of the PROMINENT trial.

METHODS

Among 108,431 individuals from the Copenhagen General Population Study (CGPS), those who met the key inclusion criteria of the PROMINENT trial were analyzed to mimic the trial design. Endpoint atherosclerotic cardiovascular disease (ASCVD) was cardiovascular death, myocardial infarction, ischemic stroke, and coronary revascularization as defined in PROMINENT.

RESULTS

In the PROMINENT trial, treatment with pemafibrate resulted in -7 mg/dL (-0.18 mmol/L; -18 %) change in remnant cholesterol, +10 mg/dL (+0.26 mmol/L; +12 %) LDL cholesterol, and +5 mg/dL (+0.05 g/L; +5 %) apolipoprotein B. In the CGPS mimicking PROMINENT, the estimated hazard ratios for ASCVD were 0.97 (95 % confidence interval: 0.94-0.99) for a -7 mg/dL (-0.18 mmol/L) change in remnant cholesterol, 1.04 (1.01-1.07) for a +10 mg/dL (+0.26 mmol/L) change in LDL cholesterol, and 1.02 (1.01-1.03) for a +5 mg/dL (+0.05 g/L) change in apolipoprotein B. When combining absolute changes in remnant cholesterol, LDL cholesterol, and apolipoprotein B, the estimated hazard ratio for ASCVD was 1.05 (0.96-1.14) in the CGPS mimicking PROMINENT compared to 1.03 (0.91-1.15) in the PROMINENT trial.

CONCLUSIONS

Absolute mass changes in remnant cholesterol, LDL cholesterol, and apolipoprotein B can explain results of the PROMINENT trial. The 3 mg/dL (0.08 mmol/L) higher total atherogenic cholesterol together with 5 mg/dL (0.05 g/L) higher apolipoprotein B seem to explain the trend toward more ASCVD in the pemafibrate arm.

Triglyceride-rich lipoproteins and cardiovascular diseases

The global prevalence of cardiovascular diseases (CVD) continues to rise steadily, making it a leading cause of mortality worldwide. Atherosclerosis (AS) serves as a primary driver of these conditions, commencing silently at an early age and culminating in adverse cardiovascular events that severely impact patients' quality of life or lead to fatality. Dyslipidemia, particularly elevated levels of low-density lipoprotein cholesterol (LDL-C), plays a pivotal role in AS pathogenesis as an independent risk factor. Research indicates that abnormal LDL-C accumulation within arterial walls acts as a crucial trigger for atherosclerotic plaque formation. As the disease progresses, plaque accumulation may rupture or dislodge, resulting in thrombus formation and complete blood supply obstruction, ultimately causing myocardial infarction, cerebral infarction, and other common adverse cardiovascular events. Despite adequate pharmacologic therapy targeting LDL-C reduction, patients with cardiometabolic abnormalities remain at high risk for disease recurrence, highlighting the importance of addressing lipid risk factors beyond LDL-C. Recent attention has focused on the causal relationship between triglycerides, triglyceride-rich lipoproteins (TRLs), and their remnants in AS risk. Genetic, epidemiologic, and clinical studies suggest a causal relationship between TRLs and their remnants and the increased risk of AS, and this dyslipidemia may be an independent risk factor for adverse cardiovascular events. Particularly in patients with obesity, metabolic syndrome, diabetes, and chronic kidney disease, disordered TRLs and its remnants levels significantly increase the risk of atherosclerosis and cardiovascular disease development. Accumulation of over-synthesized TRLs in plasma, impaired function of enzymes involved in TRLs lipolysis, and impaired hepatic clearance of cholesterol-rich TRLs remnants can lead to arterial deposition of TRLs and its remnants, promoting foam cell formation and arterial wall inflammation. Therefore, understanding the pathogenesis of TRLs-induced AS and targeting it therapeutically could slow or impede AS progression, thereby reducing cardiovascular disease morbidity and mortality, particularly coronary atherosclerotic heart disease.

Assessment of post-myocardial infarction lipid levels and management: Results from a tertiary care hospital of Pakistan

BACKGROUND

Lipid treatment practices and levels in post-acute myocardial infarction (AMI) patients, which are crucial for secondary prevention.

AIM

To evaluate the lipid treatment practices and lipid levels in post-myocardial infarction (MI) patients at a tertiary care hospital in Pakistan.

METHODS

In this cross-sectional study, we analyzed patients who had experienced their first AMI event in the past 3 years. We assessed fasting and non-fasting lipid profiles, reviewed statin therapy prescriptions, and examined patient compliance. The recommended dose was defined as rosuvastatin ≥ 20 mg or atorvastatin ≥ 40 mg, with target total cholesterol levels set at < 160 mg/dL and target low-density lipoprotein cholesterol (LDL-C) at < 55 mg/dL.

RESULTS

Among 195 patients, 71.3% were male, and the mean age was 57.1 ± 10.2 years. The median duration since AMI was 36 (interquartile range: 10-48) months and 60% were diagnosed with ST-segment elevation MI. Only 13.8% of patients were advised to undergo lipid profile testing after AMI, 88.7% of patients were on the recommended statin therapy, and 91.8% of patients were compliant with statin therapy. Only 11.5% had LDL-C within the target range and 71.7% had total cholesterol within the target range. Hospital admission in the past 12 months was reported by 14.4%, and the re-admission rate was significantly higher among non-compliant patients (37.5% vs 5.6%). Subsequent AMI event rate was also significantly higher among non-compliant patients (43.8% vs 11.7%).

CONCLUSION

Our study highlights that while most post-AMI patients received the recommended minimum statin therapy dose, the inadequate practice of lipid assessment may compromise therapy optimization and raise the risk of subsequent events.

Research trends in lipid-lowering therapies for coronary heart disease combined with hyperlipidemia: a bibliometric study and visual analysis

Background

Cardiovascular disease (CVD) poses a significant global health and economic challenge, with atherosclerosis being a primary cause. Over the past 40 years, substantial research has been conducted into the prevention and reversal of atherosclerosis, resulting in the development of lipid-lowering agents such as statins and fibrates. Despite the extensive literature and formulation of numerous therapeutic guidelines in this domain, a comprehensive bibliometric analysis of the current research landscape and trends has not been performed. This study aimed to elucidate the evolution and milestones of research into lipid-lowering treatments for coronary heart disease (CHD) in conjunction with hyperlipidemia through bibliometric analysis, offering insights into future directions for treatment strategies.

Methods

This study examined publications from 1986 to 2023 retrieved from the Web of Science database (Core Collection). Utilizing tools such as VOSviewer, Pajek, and CiteSpace, we analyzed publication and citation numbers, H-indexes, contributions by countries and institutions, authorship, journal sources, and keyword usage to uncover research trajectories and areas of focus.

Results

Our analysis of 587 publications revealed a recent surge in research output, particularly post-2003. The American Journal of Cardiology published the highest number of studies, with 40 articles, whereas Circulation received the highest number of citations (6,266). Key contributors included the United States, Japan, and China, with the United States leading in citation numbers and the H-index. Harvard University and Leiden University emerged as pivotal institutions, and Professors J. Wouter Jukema and Robert P. Giugliano were identified as leading experts. Keyword analysis disclosed five thematic clusters, indicating a shift in research towards new drug combinations and strategies, signaling future research directions.

Conclusion

The last 4 decades have seen a notable rise in publications on lipid-lowering therapies for CHD and hyperlipidemia, with the United States retaining world-leading status. The increase in international collaboration aids the shift towards research into innovative lipid-lowering agents and therapeutic approaches. PCSK9 inhibitors and innovative combination therapies, including antisense oligonucleotides and angiopoietin-like protein 3 inhibitors, provide avenues for future research, intending to maximize the safety and efficacy of treatment approaches.

The effect of fibrates on lowering low-density lipoprotein cholesterol and cardiovascular risk reduction: a systemic review and meta-analysis

AIMS

The effect of fibrate treatment on cardiovascular risk is inconsistent. This meta-analysis aimed to assess the effect of fibrates on major adverse cardiovascular outcome (MACE) reduction.

METHODS AND RESULTS

PubMed, Embase, and Cochrane library databases were searched up to February 2023 for randomized controlled trials comparing fibrate therapy against placebo and reporting cardiovascular outcomes and lipid profile changes. The primary outcome was the clinical outcomes of each trial that most closely corresponding to MACE, a composite of cardiovascular death, acute myocardial infarction, stroke, and coronary revascularization. A pre-specified meta-regression analysis to examine the relationship between the changes in lipid levels after fibrate treatment and the risk of MACE was also performed. Twelve trials were selected for final analysis, with 25 781 patients and 2741 MACEs in the fibrate group and 27 450 patients and 3754 MACEs in the control group. Overall, fibrate therapy was associated with decreased risk of MACE [RR 0.87, 95% confidence interval (CI) 0.81-0.94] with moderate heterogeneity (I2 = 47%). In meta-regression analysis, each 1 mmol/L reduction in low-density lipoprotein cholesterol (LDL-C) after fibrate treatment reduced MACE (RR 0.71, 95% CI 0.49-0.94, P = 0.01), while triglyceride level changes did not show a significant association (RR per 1mmol/L reduction 0.96, 95% CI 0.53-1.40, P = 0.86). A sensitivity analysis with the composite outcome of cardiovascular death or acute myocardial infarction produced similar results.

CONCLUSION

Treatment with fibrates was associated with decreased risk of MACE. The reduction in MACE risk with fibrate therapy appears to be attributable to LDL-C reduction rather than a decrease in triglyceride levels.

Heterogeneity of diabetic dyslipidemia, data from the NHANES (2011-2016)

Epidemiologic studies have demonstrated that diabetes amplifies the effects of dyslipidemia as a risk factor for cardiovascular disease (CVD). A better understanding of lipid profiles is important for lipid-lowering treatment and reducing cardiovascular risk in populations with diabetes. To describe the dyslipidemia patterns in patient with and without diabetes in the adult US population. Data from National Health and Nutrition Examination Survey (NHANES) 2011 to 2016 was analyzed. Surprisingly, 49.9% of the people with diabetes have both normal triglycerides (TGs) and normal high-density lipoprotein cholesterol (HDL-C). 33.4% of the people with diabetes have elevated TGs and 36.1% of them have low HDL-C. Only 19.3% of them have both elevated TGs and low HDL-C. Among people without diabetes, 67.5% have normal TGs and normal HDL-C, 28.0% have elevated TGs, 23.9% have low HDL-C and 8.8% have both elevated TGs and low HDL-C. The differences in the proportions of individuals with both elevated TGs and low HDL-C between the diabetic group and the nondiabetic group were more obvious in females: 7.7% in women without diabetes and 22.7% in women with diabetes. The proportion of individuals in the TG↑HDL-C↓group in the population with diabetes exhibited a decreasing trend in age groups > 30 years old, and the 30 to 40 years group of individuals with diabetes had the highest proportion of atherogenic dyslipidemia. The low-density lipoprotein cholesterol (LDL-C) to apoB ratio is generally lower in people with diabetes, with the lowest level in the TG↑HDL-C↓group. Dyslipidemia patterns in diabetes patients are highly heterogeneous. Deep phenotyping sub-groups of dyslipidemia is warranted to identify higher-risk patients for evaluation of non-LDL-C therapies. This explained at least partially of the difficult search for novel therapies in the post-LDL-C era.

Prognostic Value and Relative Cutoffs of Triglycerides Predicting Cardiovascular Outcome in a Large Regional-Based Italian Database

BACKGROUND

Despite longstanding epidemiologic data on the association between increased serum triglycerides and cardiovascular events, the exact level at which risk begins to rise is unclear. The Working Group on Uric Acid and Cardiovascular Risk of the Italian Society of Hypertension has conceived a protocol aimed at searching for the prognostic cutoff value of triglycerides in predicting cardiovascular events in a large regional-based Italian cohort.

METHODS AND RESULTS

Among 14 189 subjects aged 18 to 95 years followed-up for 11.2 (5.3-13.2) years, the prognostic cutoff value of triglycerides, able to discriminate combined cardiovascular events, was identified by means of receiver operating characteristic curve. The conventional (150 mg/dL) and the prognostic cutoff values of triglycerides were used as independent predictors in separate multivariable Cox regression models adjusted for age, sex, body mass index, total and high-density lipoprotein cholesterol, serum uric acid, arterial hypertension, diabetes, chronic renal disease, smoking habit, and use of antihypertensive and lipid-lowering drugs. During 139 375 person-years of follow-up, 1601 participants experienced cardiovascular events. Receiver operating characteristic curve showed that 89 mg/dL (95% CI, 75.8-103.3, sensitivity 76.6, specificity 34.1, P<0.0001) was the prognostic cutoff value for cardiovascular events. Both cutoff values of triglycerides, the conventional and the newly identified, were accepted as multivariate predictors in separate Cox analyses, the hazard ratios being 1.211 (95% CI, 1.063-1.378, P=0.004) and 1.150 (95% CI, 1.021-1.295, P=0.02), respectively.

CONCLUSIONS

Lower (89 mg/dL) than conventional (150 mg/dL) prognostic cutoff value of triglycerides for cardiovascular events does exist and is associated with increased cardiovascular risk in an Italian cohort.

A facile synthesis of 2-(4-((4-chlorophenyl)(hydroxy)methyl) phenoxy)-2-methylpropanoic acid: Metabolite of anti-hyperlipidemic drug Fenofibrate

Synthesis and characterization of drug metabolites has emerged as an important area of research in consideration to the significant contribution of studies on metabolites in drug research. The present work comprises synthesis of 2-(4-((4-chlorophenyl)(hydroxy)methyl) phenoxy)-2-methylpropanoic acid, a metabolite of anti-hyperlipidemic drug fenofibrate. The desired compound was prepared by two different synthetic routes. The ketone group of fenofibric acid was reduced using sodium borohydride in one route whereas the hydrolysis of isopropyl ester of the reduced fenofibrate was achieved by the mild alkaline hydrolysis in the other path. Both the ways of synthesis furnished the desired compound in excellent yield and purity. The new synthetic congener was characterized by spectroscopic methods.

A bifunctional anti-PCSK9 scFv/Exendin-4 fusion protein exhibits enhanced lipid-lowering effects via targeting multiple signaling pathways in HFD-fed mice

Fusion protein which encompasses more than one functional component, has become one of the most important representatives of macromolecular drugs for disease treatment since that monotherapy itself might not be effective enough to eradicate the disease. In this study, we sought to construct a bifunctional antibody fusion protein by fusing anti-PCSK9 scFv with Exendin-4 for simultaneously lowering both LDL-C and TG. Firstly, three Ex4-anti-PCSK9 scFv fusion proteins were constructed by genetically connecting the C-terminal of Exendin-4 to the N-terminal of anti-PCSK9 scFv through various flexible linker peptides (G4S)n (n = 2, 3, 4). After soluble expression in E. coli, the most potent Ex4-(G4S)4-anti-PCSK9 scFv fusion protein was selected based on in vitro activity assays. Then, we investigated the in vivo therapeutic effects of Ex4-(G4S)4-anti-PCSK9 scFv on the serum lipid profile and bodyweight changes as well as underlying molecular mechanism in HFD-fed C57BL/6 mice. The data showed that Ex4-(G4S)4-anti-PCSK9 scFv exhibits enhanced effects of lowering both LDL-C and TG in serum, reducing food intake and body weight via blocking PCSK9/LDLR, activating AMPK/SREBP-1 pathways, and up-regulating sirt6. Conclusively, Ex4-(G4S)4-anti-PCSK9 has the potential to serve as a promising therapeutic agent for effectively treating dyslipidemia with high levels of both LDL-C and TG.

Age and the Residual Risk of Cardiovascular Disease following Low Density Lipoprotein-Cholesterol Exposure

We believe that there is sufficient evidence from basic science, longitudinal cohort studies and randomised controlled trials which validates the low-density lipoprotein cholesterol (LDL-C) or lipid hypothesis. It is important that we can communicate details of the cardiovascular disease (CVD) risk reduction that the average patient could expect depending on the scale of LDL-C decrease following lipid lowering therapy. It is also essential that residual risk (ResR) of CVD be highlighted. To achieve this aim by using existing trial evidence, we developed mathematical models initially for relative risk reduction (RRR) and absolute risk (AR) reduction and then showed that despite optimising LDL-C levels, a considerable degree of ResR remains that is dependent on AR. Age is significantly associated with AR (odds ratio: 1.02, 95% confidence intervals: 1.01-1.04) as was previously demonstrated by analysing the Whickham study cohort using a logistic regression model (age remaining significant even when all the other significant risk factors such as sex, smoking, systolic blood pressure, diabetes and family history were included in the regression model). A discussion of a paper by Ference et al. provided detailed evidence of the relationship between age and AR, based on lifetime LDL-C exposure. Finally, we discussed non-traditional CVD risk factors that may contribute to ResR based on randomised controlled trials investigating drugs improving inflammation, thrombosis, metabolic and endothelial status.

HDL as a Treatment Target: Should We Abandon This Idea?

PURPOSE OF REVIEW

High-density lipoproteins (HDL) have long been regarded as an antiatherogenic lipoprotein species by virtue of their role in reverse cholesterol transport (RCT), as well as their established anti-inflammatory and antioxidant properties. For decades, HDL have been an extremely appealing therapeutic target to combat atherosclerotic cardiovascular diseases (ASCVD).

RECENT FINDINGS

Unfortunately, neither increasing HDL with drugs nor direct infusions of reconstituted HDL have convincedly proven to be positive strategies for cardiovascular health, raising the question of whether we should abandon the idea of considering HDL as a treatment target. The results of two large clinical trials, one testing the latest CETP inhibitor Obicetrapib and the other testing the infusion of patients post-acute coronary events with reconstituted HDL, are still awaited. If they prove negative, these trials will seal the fate of HDL as a direct therapeutic target. However, using HDL as a therapeutic agent still holds promise if we manage to optimize their beneficial properties for not only ASCVD but also outside the cardiovascular field.

Drug Therapy for Hypertriglyceridemia and Familial Chylomicronemia Syndrome: Focus on Volnesorsen

Volanesorsen is a new medication that may soon be used in the treatment of hypertriglyceridemia and familial chylomicronemia syndrome (FCS). Volanesorsen works via binding to Apo C-III mRNA and degrading that mRNA, thus decreasing the synthesis of Apo C-III. This decreased synthesis of Apo C-III will increase the binding of triglycerides to LDL receptors and decrease triglyceride plasma levels. It is important to note that currently there are 3 other medication classes available for the treatment of hypertriglyceridemia, including niacin, fish oil/omega-3-fatty acids, and fibrates. However, there are no Food and Drug Administration-approved medications to treat FCS. Recently, volanesorsen was approved in the European Union for the treatment of FCS, but that indication was denied in the United States by the Food and Drug Administration. This was due to the side effects of the drug. Volanesorsen may cause a decrease in platelet count, renal toxicity, and elevate liver enzymes. The current drug regimen for volanesorsen consists of 285 mg once a week by subcutaneous injection, with a recommendation to immediately stop the medication if any of these side effects are noted, to prevent long-term complications. With these side effects reported, fish oil/omega-3-fatty acids seem likely the best choice when it comes to treating hypertriglyceridemia. If FCS is debilitating or greatly affecting the patient's life, then one could recommend volanesorsen. Otherwise, at this time, the side effects of volanesorsen may be too severe to justify its use for mild episodes of FCS or hypertriglyceridemia.

Severe hypertriglyceridemia: Existing and emerging therapies

Severe hypertriglyceridemia (sHTG), defined as a triglyceride (TG) concentration ≥ 500 mg/dL (≥ 5.7 mmol/L) is an important risk factor for acute pancreatitis. Although lifestyle, some medications, and certain conditions such as diabetes may lead to HTG, sHTG results from a combination of major and minor genetic defects in proteins that regulate TG lipolysis. Familial chylomicronemia syndrome (FCS) is a rare disorder caused by complete loss of function in lipoprotein lipase (LPL) or LPL activating proteins due to two homozygous recessive traits or compound heterozygous traits. Multifactorial chylomicronemia syndrome (MCS) and sHTG are due to the accumulation of rare heterozygous variants and polygenic defects that predispose individuals to sHTG phenotypes. Until recently, treatment of sHTG focused on lifestyle interventions, control of secondary factors, and nonselective pharmacotherapies that had modest TG-lowering efficacy and no corresponding reductions in atherosclerotic cardiovascular disease events. Genetic discoveries have allowed for the development of novel pathway-specific therapeutics targeting LPL modulating proteins. New targets directed towards inhibition of apolipoprotein C-III (apoC-III), angiopoietin-like protein 3 (ANGPTL3), angiopoietin-like protein 4 (ANGPTL4), and fibroblast growth factor-21 (FGF21) offer far more efficacy in treating the various phenotypes of sHTG and opportunities to reduce the risk of acute pancreatitis and atherosclerotic cardiovascular disease events.

Peroxisome Proliferator-Activated Receptor α in Lipoprotein Metabolism and Atherosclerotic Cardiovascular Disease

Peroxisome proliferator-activated receptors (PPARs) are a group of ligand-binding transcription factors with pivotal action in regulating pleiotropic signaling pathways of energetic metabolism, immune responses and cell proliferation and differentiation. A significant body of evidence indicates that the PPARα receptor is an important modulator of plasma lipid and lipoprotein metabolism, with pluripotent effects influencing the lipid and apolipoprotein cargo of both atherogenic and antiatherogenic lipoproteins and their functionality. Clinical evidence supports an important role of PPARα agonists (fibric acid derivatives) in the treatment of hypertriglyceridemia and/or low high-density lipoprotein (HDL) cholesterol levels, although the effects of clinical trials are contradictory and point to a reduction in the risk of nonfatal and fatal myocardial infarction events. In this manuscript, we provide an up-to-date critical review of the existing relevant literature.

The Role of Triglyceride-rich Lipoproteins and Their Remnants in Atherosclerotic Cardiovascular Disease

Atherosclerotic cardiovascular disease (ASCVD) is the world's leading cause of death. ASCVD has multiple mediators that therapeutic interventions target, such as dyslipidaemia, hypertension, diabetes and heightened systemic inflammatory tone, among others. LDL cholesterol is one of the most well-studied and established mediators targeted for primary and secondary prevention of ASCVD. However, despite the strength of evidence supporting LDL cholesterol reduction by multiple management strategies, ASCVD events can still recur, even in patients whose LDL cholesterol has been very aggressively reduced. Hypertriglyceridaemia and elevated levels of triglyceride-rich lipoproteins (TRLs) may be key contributors to ASCVD residual risk. Several observational and genetic epidemiological studies have highlighted the causal role of triglycerides within the TRLs and/or their remnant cholesterol in the development and progression of ASCVD. TRLs consist of intestinally derived chylomicrons and hepatically synthesised very LDL. Lifestyle modification has been considered the first line intervention for managing hypertriglyceridaemia. Multiple novel targeted therapies are in development, and have shown efficacy in the preclinical and clinical phases of study in managing hypertriglyceridaemia and elevated TRLs. This comprehensive review provides an overview of the biology, pathogenicity, epidemiology, and genetics of triglycerides and TRLs, and how they impact the risk for ASCVD. In addition, we provide a summary of currently available and novel emerging triglyceride-lowering therapies in development.

Triglycerides revisited: is hypertriglyceridaemia a necessary therapeutic target in cardiovascular disease?

Despite the atherosclerotic cardiovascular disease (ASCVD) risk reduction achieved by low-density lipoprotein cholesterol (LDL-C) lowering therapy, residual ASCVD risk still exists. Previous epidemiological studies have suggested high plasma triglyceride (TG) levels as a risk factor or risk marker for ASCVD independent of LDL-C levels. In this review, we highlighted the underlying pathophysiology of hypertriglyceridaemia, the mechanistic action of therapeutic agents, the interpretation of conflicting results on recent clinical trials, and the present options for primary and secondary prevention. The benefits of fibrates-induced reduction in TG and increase in high-density lipoprotein cholesterol might outweigh the disadvantages of increasing LDL-C levels in primary prevention. In secondary CVD prevention, using eicosapentaenoic acid without docosahexaenoic acid, in addition to statins, will be beneficial. This comprehensive review may prove useful for the development of novel approaches that target hypertriglyceridaemia in future.

Efficacy and safety of pemafibrate in patients with hypertriglyceridemia in clinical settings: A retrospective study

BACKGROUND AND AIMS

Recently, pemafibrate, a selective PPARα modulator, has been developed as a treatment for hypertriglyceridemia and has attracted much attention. The aims of this study were to evaluate the efficacy and safety of pemafibrate in hypertriglyceridemia patients under clinical settings.

METHODS AND RESULTS

We evaluated changes in lipid profiles and various parameters before and after 24-week pemafibrate administration in patients with hypertriglyceridemia who had not previously taken fibrate medications. There were 79 cases included in the analysis. 24 weeks after the treatment with pemafibrate, TG was significantly reduced from 312 ± 226 to 167 ± 94 mg/dL. In addition, lipoprotein fractionation tests using PAGE method showed a significant decrease in the ratio of VLDL and remnant fractionations, which are TG-rich lipoproteins. After pemafibrate administration, body weight, HbA1c, eGFR, and CK levels were not changed, but liver injury indices such as ALT, AST, and γ-GTP were significantly improved.

CONCLUSION

In this study, pemafibrate improved the metabolism of atherosclerosis-induced lipoproteins in hypertriglyceridemia patients. In addition, it showed no off-target effects such as hepatic and renal damage or rhabdomyolysis.

Novel Selective PPARα Modulator Pemafibrate for Dyslipidemia, Nonalcoholic Fatty Liver Disease (NAFLD), and Atherosclerosis

Statins, the intestinal cholesterol transporter inhibitor (ezetimibe), and PCSK9 inhibitors can reduce serum LDL-C levels, leading to a significant reduction in cardiovascular events. However, these events cannot be fully prevented even when maintaining very low LDL-C levels. Hypertriglyceridemia and reduced HDL-C are known as residual risk factors for ASCVD. Hypertriglyceridemia and/or low HDL-C can be treated with fibrates, nicotinic acids, and n-3 polyunsaturated fatty acids. Fibrates were demonstrated to be PPARα agonists and can markedly lower serum TG levels, yet were reported to cause some adverse effects, including an increase in the liver enzyme and creatinine levels. Recent megatrials of fibrates have shown negative findings on the prevention of ASCVD, which were supposed to be due to their low selectivity and potency for binding to PPAR α. To overcome the off-target effects of fibrates, the concept of a selective PPARα modulator (SPPARMα) was proposed. Kowa Company, Ltd. (Tokyo, Japan), has developed pemafibrate (K-877). Compared with fenofibrate, pemafibrate showed more favorable effects on the reduction of TG and an increase in HDL-C. Fibrates worsened liver and kidney function test values, although pemafibrate showed a favorable effect on liver function test values and little effect on serum creatinine levels and eGFR. Minimal drug-drug interactions of pemafibrate with statins were observed. While most of the fibrates are mainly excreted from the kidney, pemafibrate is metabolized in the liver and excreted into the bile. It can be used safely even in patients with CKD, without a significant increase in blood concentration. In the megatrial of pemafibrate, PROMINENT, for dyslipidemic patients with type 2 diabetes, mild-to-moderate hypertriglyceridemia, and low HDL-C and LDL-C levels, the incidence of cardiovascular events did not decrease among those receiving pemafibrate compared to those receiving the placebo; however, the incidence of nonalcoholic fatty liver disease was lower. Pemafibrate may be superior to conventional fibrates and applicable to CKD patients. This current review summarizes the recent findings on pemafibrate.

Efficacy and Safety of Pemafibrate Versus Bezafibrate to Treat Patients with Hypertriglyceridemia: A Randomized Crossover Study

AIM

Pemafibrate is a highly selective agonist for peroxisome proliferator-activated receptor (PPAR)-α, a key regulator of lipid and glucose metabolism. We compared the efficacy and safety of pemafibrate with those of bezafibrate, a nonselective PPAR-α agonist.

METHODS

In this randomized crossover study, 60 patients with hypertriglyceridemia (fasting triglyceride [TG] ≥ 150 mg/dL) were treated with pemafibrate of 0.2 mg/day or bezafibrate of 400 mg/day for 24 weeks. The primary endpoint was percent change (%Change) from baseline in TG levels, while the secondary endpoints were %Change in high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A-I (Apo A-I) levels.

RESULTS

The %Change in TG and Apo A-I levels was significantly greater with pemafibrate than with bezafibrate (-46.1% vs. -34.7%, p＜0.001; 9.2% vs. 5.7%, p =0.018, respectively). %Change in HDL-C levels was not significantly different between the two treatments. %Change in liver enzyme levels was markedly decreased with pemafibrate than with bezafibrate. Creatinine levels significantly increased in both treatments; however, its %Change was significantly lower with pemafibrate than with bezafibrate (5.72% vs. 15.5%, p＜0.001). The incidence of adverse events (AEs) or serious AEs did not differ between the two treatments; however, the number of patients with elevated creatinine levels (≥ 0.5 mg/dL and/or 25% from baseline) was significantly higher in the bezafibrate group than in the pemafibrate group (14/60 vs. 3/60, p =0.004) [corrected].

CONCLUSION

Compared with bezafibrate, pemafibrate is more effective in decreasing TG levels and increasing Apo A-I levels and is safer regarding liver and renal function.

Remnant cholesterol as a risk factor for all-cause and cardiovascular mortality in incident peritoneal dialysis patients

BACKGROUND AND AIMS

Remnant cholesterol (RC) adversely contributes to cardiovascular disease (CVD) and overall survival in various diseases. However, its role in CVD outcomes and all-cause mortality in patients undergoing peritoneal dialysis (PD) is limited. Therefore, we aimed to investigate the association between RC and all-cause and CVD mortality in patients undergoing PD.

METHODS AND RESULTS

Based on lipid profiles recorded using standard laboratory procedures, fasting RC levels were calculated in 2710 incident patients undergoing PD who were enrolled between January 2006 and December 2017 and followed up until December 2018. Patients were divided into four groups according to the quartile distribution of baseline RC levels (Q1: <0.40 mmol/L, Q2: 0.40 to <0.64 mmol/L, Q3: 0.64 to <1.03 mmol/L, and Q4: ≥1.03 mmol/L). Associations between RC and CVD and all-cause mortality were evaluated using multivariable Cox models. During the median follow-up period of 35.4 months (interquartile range, 20.9-57.2 months), 820 deaths were recorded, of which 438 were CVD-related. Smoothing plots showed non-linear relationships between RC and adverse outcomes. The risks of all-cause and CVD mortality increased progressively through the quartiles (log-rank, p < 0.001). Using adjusted proportional hazard models, a comparison of the highest (Q4) to lowest (Q1) quartiles revealed significant increases in the hazard ratio (HR) for all-cause mortality (HR 1.95 [95% confidence interval (CI), 1.51-2.51]) and CVD mortality risk (HR 2.60 [95% CI, 1.80-3.75]).

CONCLUSION

An increased RC level was independently associated with all-cause and CVD mortality in patients undergoing PD, suggesting that RC was important clinically and required further research.

Clinical Trial Design for Triglyceride-Rich Lipoprotein-Lowering Therapies: JACC Focus Seminar 3/3

Triglyceride-rich lipoproteins (TRLs) are a source of residual risk in patients with atherosclerotic cardiovascular disease, and are indirectly correlated with triglyceride (TG) levels. Previous clinical trials studying TG-lowering therapies have either failed to reduce major adverse cardiovascular events or shown no linkage of TG reduction with event reduction, particularly when these agents were tested on a background of statin therapy. Limitations in trial design may explain this lack of efficacy. With the advent of new RNA-silencing therapies in the TG metabolism pathway, there is renewed focus on reducing TRLs for major adverse cardiovascular event reduction. In this context, the pathophysiology of TRLs, pharmacological effects of TRL-lowering therapies, and optimal design of cardiovascular outcomes trials are major considerations.

Current and Emerging Therapies for Atherosclerotic Cardiovascular Disease Risk Reduction in Hypertriglyceridemia

Hypertriglyceridemia (HTG) is a prevalent medical condition in patients with cardiometabolic risk factors and is associated with an increased risk of atherosclerotic cardiovascular disease (ASCVD), if left undiagnosed and undertreated. Current guidelines identify HTG as a risk-enhancing factor and, as a result, recommend clinical evaluation and lifestyle-based interventions to address potential secondary causes of elevated triglyceride (TG) levels. For individuals with mild to moderate HTG at risk of ASCVD, statin therapy alone or in combination with other lipid-lowering medications known to decrease ASCVD risk are guideline-endorsed. In addition to lifestyle modifications, patients with severe HTG at risk of acute pancreatitis may benefit from fibrates, mixed formulation omega-3 fatty acids, and niacin; however, evidence does not support their use for ASCVD risk reduction in the contemporary statin era. Novel therapeutics including those that target apoC-III and ANGPTL3 have shown to be safe, well-tolerated, and effective for lowering TG levels. Given the growing burden of cardiometabolic disease and risk factors, public health and health policy strategies are urgently needed to enhance access to effective pharmacotherapies, affordable and nutritious food options, and timely health care services.

Omega-3 Fatty Acids in Cardiovascular Disease and Diabetes: a Review of Recent Evidence

PURPOSE OF REVIEW

Omega-3 fatty acids (n-3 FA) lower triglycerides, have anti-inflammatory properties, and improve metabolism. Clinical evidence of cardiovascular benefit with omega-3 fatty acids is mixed. We discuss mechanisms providing biological plausibility of benefit of omega-3 fatty acids in cardiovascular risk reduction and review clinical trials investigating the benefits of prescription omega-3 fatty acids in dyslipidemia, atherosclerotic cardiovascular disease (ASCVD), and diabetes.

RECENT FINDINGS

Although early trials showed no benefit of omega-3 fatty acids in ASCVD, the REDUCE-IT trial noted significant risk reduction in ASCVD events with highly purified EPA (icosapent ethyl) use which has changed the landscape for currently available therapeutic options. However, other large trials like STRENGTH and VITAL, which used different formulations of prescription omega-3 fatty acids, did not note significant cardiovascular risk reduction. Thus the effectiveness of omega-3 fatty acids for cardiovascular disease prevention is an ongoing topic of debate. A relative paucity of studies examining benefits for glycemic outcomes in persons with diabetes exists; however, few studies have suggested lack of benefit to date. Significant residual cardiovascular risk exists for individuals with hypertriglyceridemia. Prescription omega-3 fatty acids are more commonly used for CV risk reduction in these patients. Clinical guideline statements now recommend icosapent ethyl use for selected individuals with hypertriglyceridemia to reduce cardiovascular events given recent evidence from the REDUCE-IT trial. Nonetheless, data from other large scale trials has been mixed, and future research is needed to better understand how different preparations of omega-3 may differ in their cardiovascular and metabolic effects, and the mechanisms for their benefit.

Pharmacological Utility of PPAR Modulation for Angiogenesis in Cardiovascular Disease

Peroxisome proliferator activated receptors, including PPARα, PPARβ/δ, and PPARγ, are ligand-activated transcription factors belonging to the nuclear receptor superfamily. They play important roles in glucose and lipid metabolism and are also supposed to reduce inflammation and atherosclerosis. All PPARs are involved in angiogenesis, a process critically involved in cardiovascular pathology. Synthetic specific agonists exist for all PPARs. PPARα agonists (fibrates) are used to treat dyslipidemia by decreasing triglyceride and increasing high-density lipoprotein (HDL) levels. PPARγ agonists (thiazolidinediones) are used to treat Type 2 diabetes mellitus by improving insulin sensitivity. PPARα/γ (dual) agonists are supposed to treat both pathological conditions at once. In contrast, PPARβ/δ agonists are not in clinical use. Although activators of PPARs were initially considered to have favorable effects on the risk factors for cardiovascular disease, their cardiovascular safety is controversial. Here, we discuss the implications of PPARs in vascular biology regarding cardiac pathology and focus on the outcomes of clinical studies evaluating their benefits in cardiovascular diseases.

Atherogenic Dyslipidemias: Unmet Needs and the Therapeutic Potential of Emerging and Novel Approaches and Drugs

Innovative lipid-modifying agents are valuable resources to improve the control of atherogenic dyslipidemias and reduce the lipid-related residual cardiovascular risk of patients with intolerance or who are not fully responsive to a consolidated standard of care (statins plus ezetimibe). Moreover, some of the upcoming compounds potently affect lipid targets that are thus far considered "unmodifiable". The present paper is a viewpoint aimed at presenting the incremental metabolic and cardiovascular benefits of the emerging lipid-modulating agents and real-life barriers, hindering their prescription by physicians and their assumption by patients, which need to be worked out for a more diffuse and appropriate drug utilization.

Very low HDL levels: clinical assessment and management

In individuals with very low high-density lipoprotein (HDL-C) cholesterol, such as Tangier disease, LCAT deficiency, and familial hypoalphalipoproteinemia, there is an increased risk of premature atherosclerosis. However, analyzes based on comparisons of populations with small variations in HDL-C mediated by polygenic alterations do not confirm these findings, suggesting that there is an indirect association or heterogeneity in the pathophysiological mechanisms related to the reduction of HDL-C. Trials that evaluated some of the HDL functions demonstrate a more robust degree of association between the HDL system and atherosclerotic risk, but as they were not designed to modify lipoprotein functionality, there is insufficient data to establish a causal relationship. We currently have randomized clinical trials of therapies that increase HDL-C concentration by various mechanisms, and this HDL-C elevation has not independently demonstrated a reduction in the risk of cardiovascular events. Therefore, this evidence shows that (a) measuring HDL-C as a way of estimating HDL-related atheroprotective system function is insufficient and (b) we still do not know how to increase cardiovascular protection with therapies aimed at modifying HDL metabolism. This leads us to a greater effort to understand the mechanisms of molecular action and cellular interaction of HDL, completely abandoning the traditional view focused on the plasma concentration of HDL-C. In this review, we will detail this new understanding and the new horizon for using the HDL system to mitigate residual atherosclerotic risk.

The plasma phospholipidome of the bottlenose dolphin (Tursiops truncatus) is modulated by both sex and developmental stage

Lipidomics represent a valid complementary tool to the biochemical analysis of plasma in humans. However, in cetaceans, these tools have been unexplored. Here, we evaluated how the plasma lipid composition of Tursiops truncatus is modulated by developmental stage and sex, aiming at a potential use of lipidomics in integrated strategies to monitor cetacean health. We characterized the fatty acid profile and detected a total of 26 fatty acids in T. truncatus plasma. The most abundant fatty acids were palmitic acid (C16:0), stearic acid (C18:0) and oleic acid (C18:1n-9). Interestingly, there are consistent differences between the fatty acid profile of mature female and mature male specimens. Phospholipidome analysis identified 320 different lipid species belonging to phosphatidylcholine (PC, 105 lipid species), lysophosphatidylcholine (42), phosphatidylethanolamine (PE, 67), lysophosphatidylethanolamine (18), phosphatidylglycerol (14), lysophosphatidylglycerol (8), phosphatidylinositol (14), lysophosphatidylinositol (2), phosphatidylserine (3), sphingomyelin (45) and ceramides (2) classes. The statistical analysis of the phospholipidome showed that its composition allows discriminating mature animals between sexes and mature males from immature males. Notably, discrimination between sexes is mainly determined by the contents of PE plasmalogens and lysophospholipids (LPC and LPE), while the differences between mature and immature male animals were mainly determined by the levels of PC lipids. This is the first time that a correlation between developmental stage and sex and the lipid composition of the plasma has been established in cetaceans. Being able to discern between age and sex-related changes is an encouraging step towards using these tools to also detect differences related to disease/dysfunction processes.

A Nutraceutical Compound Containing a Low Dose of Monacolin K, Polymethoxyflavones, Phenolic Acids, Flavonoids, and Hydroxytyrosol Improves HDL Functionality

BACKGROUND

In earlier studies, it has been observed that 8-week treatment with a novel nutraceutical compound (NC) containing low monacolin K dose, polymethoxyflavones, phenolic acids, flavonoids, and hydroxytyrosol improves lipid profile and endothelial function and reduces the level of oxidized low-density lipoprotein (oxLDL). We hypothesize that this effect might be, at least in part, explained by positive modulation exerted by the NC on the atheroprotective function of high-density lipoprotein (HDL).

AIM

This study aimed to evaluate whether the NC could influence determinants of HDL function.

METHODS

Forty-five subjects with low-moderate dyslipidaemia were enrolled and treated for 8 weeks with the NC, followed by 4 weeks of washout. Blood samples were collected at every time point to evaluate changes in lipid profile, endothelial function, oxLDL, and markers of HDL function, such as the anti-oxidant activities of paraoxonase-1, glutathione peroxidase-3 (Gpx3), lipoprotein-phospholipase A2 (Lp-PLA2), and pro-oxidant activity of myeloperoxidase (MPO).

RESULTS

Although the concentration of HDL-C did not change, the activity of Lp-PLA2 significantly decreased upon treatment (-11.6%, p<0.001) and returned to baseline level 4 weeks after the end of treatment. In contrast, Gpx3 increased after treatment (+5%, p<0.01) and remained unvaried after 4 weeks. Both MPO activity and concentration significantly decreased after the washout period (-33 and 32%, p<0.001).

CONCLUSION

For the first time, it was found that the administration of an NC with beneficial effects on lipid homeostasis also positively impacts HDL function by improving the balance between protective and damaging determinants. Further investigation is required to corroborate our findings.

Residual Atherosclerotic Cardiovascular Disease Risk: Focus on Non-High-Density Lipoprotein Cholesterol

Cardiovascular disease (CVD) caused by atherosclerosis is the leading cause of death worldwide. The level of low-density lipoprotein cholesterol (LDL-C), considered as the initiator of atherosclerosis, is the most widely used predictor for CVD risk and LDL-C has been the primary target for lipid-lowering therapies. However, residual CVD risk remains high even with very low levels of LDL-C. This residual CVD risk may be due to remnant cholesterol, high triglyceride levels, and low high-density lipoprotein cholesterol (HDL-C). Non-high density lipoprotein cholesterol (non-HDL-C), which is calculated as total cholesterol minus HDL-C (and represents the cholesterol content of all atherogenic apolipoprotein B-containing lipoproteins), has emerged as a better risk predictor for CVD than LDL-C and an alternative target for CVD risk reduction. Major international guidelines recommend evaluating non-HDL-C as part of atherosclerotic CVD risk assessment, especially in people with high triglycerides, diabetes, obesity, or very low LDL-C. A non-HDL-C target of <130 mg/dL (3.4 mmol/L) has been recommended for patients at very high risk, which is 30 mg/dL (0.8 mmol/L) higher than the corresponding LDL-C target goal. Non-HDL-C lowering approaches include reducing LDL-C and triglyceride levels, increasing HDL-C, or targeting multiple risk factors simultaneously. However, despite the growing evidence for the role of non-HDL-C in residual CVD risk, and recommendations for its assessment in major guidelines, non-HDL-C testing is not routinely done in clinical practice. Thus, there is a need for increased awareness of the need for non-HDL-C testing for ascertaining CVD risk and concomitant prevention of CVD.

Comparison of the effects of triglyceride variability and exposure estimate on clinical prognosis in diabetic patients

BACKGROUND

Hypertriglyceridemia is an important feature of dyslipidemia in type 1 and type 2 diabetic patients and associated with the development of atherosclerotic cardiovascular disease. Recently, variability of lipid profile has been suggested as a residual risk factor for cardiovascular disease. This study compared the clinical impact of serum triglyceride variability, and their cumulative exposure estimates on cardiovascular prognosis in diabetic patients.

METHODS

A total of 25,933 diabetic patients who had serum triglyceride levels measured at least 3 times and did not have underlying malignancy, myocardial infarction (MI), and stroke during the initial 3 years (modeling phase) were selected from three tertiary hospitals. They were divided into a high/low group depending on their coefficient of variation (CV) and cumulative exposure estimate (CEE). Incidence of major adverse event (MAE), a composite of all-cause death, MI, and stroke during the following 5 years were compared between groups by multivariable analysis after propensity score matching.

RESULTS

Although there was a slight difference, both the high CV group and the high CEE group had a higher cardiovascular risk profile including male-dominance, smoking, alcohol, dyslipidemia, and chronic kidney disease compared to the low groups. After the propensity score matching, the high CV group showed higher MAE incidence compared to the low CV group (9.1% vs 7.7%, p = 0.01). In contrast, there was no significant difference of MAE incidence between the high CEE group and the low CEE group (8.6% vs 9.1%, p = 0.44). After the multivariable analysis with further adjustment for potential residual confounding factors, the high CV was suggested as an independent risk predictor for MAE (HR 1.19 [95% CI 1.03-1.37]).

CONCLUSION

Visit-to-visit variability of triglyceride rather than their cumulative exposure is more strongly related to the incidence of MAE in diabetic patients.

Increased residual cardiovascular risk in U.S. veterans with moderately-elevated baseline triglycerides and well-controlled LDL-C levels on statins

Background

Recent studies have demonstrated a causal role for elevated triglycerides (TG) in incident cardiovascular (CV) events in patients with established coronary heart disease (CHD) and those with CV risk factors alone, particularly diabetes.

Objective

Using a large cohort of U.S. veterans with statin-controlled LDL-C levels (40–100 mg/dL), we explored residual CV risk among patients with elevated baseline TG levels (150–499 mg/dL) vs. those with normal TG levels (<150 mg/dL).

Methods

We identified veterans receiving a statin but not a TG-lowering agent from the VA electronic health records database, from 2010 to 2015. We compared composite CV event rates (MI, stroke, unstable angina, coronary revascularization, and CV death) between the elevated TG and normal TG groups. We stratified the study cohort according to 3 CV risk groups: (1) no diabetes and no prior CV event, (2) diabetes and no prior CV event, and (3) prior CV event. We calculated crude event rates, rate ratios, and event rate ratios adjusted for age, sex, systolic blood pressure, estimated glomerular filtration rate, and weight.

Results

The cohort included 396,189 veterans (predominantly male and white) of whom 109,195 (28%) had elevated TG levels. Those with elevated TG were younger (age 73 vs. 77 years) and had a higher body mass index (31.3 vs. 28.3 Kg/M²). The overall composite crude and adjusted rate ratios comparing the elevated and normal TG groups were 1.10 (1.09, 1.12) and 1.05 (1.03, 1.06), respectively. For CV risk groups 1, 2 and 3, the adjusted rate ratios comparing the elevated and normal TG groups were 0.99 (0.96, 1.02), 1.05 (1.02, 1.08), and 1.07 (1.04, 1.10), respectively. An association of increased rate ratios did not hold for fatal events.

Conclusion

Those with elevated TG levels and well-controlled LDL-C on statins showed a modest increase in CV events compared to those with normal TG. Elevated TG levels were associated with increased CV events in patients with established CV disease and with diabetes only, suggesting that elevated TG levels are associated with a similar degree of residual risk in high-risk primary prevention and secondary prevention settings.

Alterations of HDL's to piHDL's Proteome in Patients with Chronic Inflammatory Diseases, and HDL-Targeted Therapies

Chronic inflammatory diseases, such as rheumatoid arthritis, steatohepatitis, periodontitis, chronic kidney disease, and others are associated with an increased risk of atherosclerotic cardiovascular disease, which persists even after accounting for traditional cardiac risk factors. The common factor linking these diseases to accelerated atherosclerosis is chronic systemic low-grade inflammation triggering changes in lipoprotein structure and metabolism. HDL, an independent marker of cardiovascular risk, is a lipoprotein particle with numerous important anti-atherogenic properties. Besides the essential role in reverse cholesterol transport, HDL possesses antioxidative, anti-inflammatory, antiapoptotic, and antithrombotic properties. Inflammation and inflammation-associated pathologies can cause modifications in HDL's proteome and lipidome, transforming HDL from atheroprotective into a pro-atherosclerotic lipoprotein. Therefore, a simple increase in HDL concentration in patients with inflammatory diseases has not led to the desired anti-atherogenic outcome. In this review, the functions of individual protein components of HDL, rendering them either anti-inflammatory or pro-inflammatory are described in detail. Alterations of HDL proteome (such as replacing atheroprotective proteins by pro-inflammatory proteins, or posttranslational modifications) in patients with chronic inflammatory diseases and their impact on cardiovascular health are discussed. Finally, molecular, and clinical aspects of HDL-targeted therapies, including those used in therapeutical practice, drugs in clinical trials, and experimental drugs are comprehensively summarised.

New, Novel Lipid-Lowering Agents for Reducing Cardiovascular Risk: Beyond Statins

Statins are the cornerstone of the prevention and treatment of atherosclerotic cardiovascular disease (ASCVD). However, even under optimal statin therapy, a significant residual ASCVD risk remains. Therefore, there has been an unmet clinical need for novel lipid-lowering agents that can target low-density lipoprotein cholesterol (LDL-C) and other atherogenic particles. During the past decade, several drugs have been developed for the treatment of dyslipidemia. Inclisiran, a small interfering RNA that targets proprotein convertase subtilisin/kexin type 9 (PCSK9), shows comparable effects to that of PCSK9 monoclonal antibodies. Bempedoic acid, an ATP citrate lyase inhibitor, is a valuable treatment option for the patients with statin intolerance. Pemafibrate, the first selective peroxisome proliferator-activated receptor alpha modulator, showed a favorable benefit-risk balance in phase 2 trial, but the large clinical phase 3 trial (PROMINENT) was recently stopped for futility based on a late interim analysis. High dose icosapent ethyl, a modified eicosapentaenoic acid preparation, shows cardiovascular benefits. Evinacumab, an angiopoietin-like 3 (ANGPTL3) monoclonal antibody, reduces plasma LDL-C levels in patients with refractory hypercholesterolemia. Novel antisense oligonucleotides targeting apolipoprotein C3 (apoC3), ANGPTL3, and lipoprotein(a) have significantly attenuated the levels of their target molecules with beneficial effects on associated dyslipidemias. Apolipoprotein A1 (apoA1) is considered as a potential treatment to exploit the athero-protective effects of high-density lipoprotein cholesterol (HDL-C), but solid clinical evidence is necessary. In this review, we discuss the mode of action and clinical outcomes of these novel lipid-lowering agents beyond statins.

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

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

HDL as Bidirectional Lipid Vectors: Time for New Paradigms

The anti-atherogenic properties of high-density lipoproteins (HDL) have been explained mainly by reverse cholesterol transport (RCT) from peripheral tissues to the liver. The RCT seems to agree with most of the negative epidemiological correlations between HDL cholesterol levels and coronary artery disease. However, therapies designed to increase HDL cholesterol failed to reduce cardiovascular risk, despite their capacity to improve cholesterol efflux, the first stage of RCT. Therefore, the cardioprotective role of HDL may not be explained by RCT, and it is time for new paradigms about the physiological function of these lipoproteins. It should be considered that the main HDL apolipoprotein, apo AI, has been highly conserved throughout evolution. Consequently, these lipoproteins play an essential physiological role beyond their capacity to protect against atherosclerosis. We propose HDL as bidirectional lipid vectors carrying lipids from and to tissues according to their local context. Lipid influx mediated by HDL appears to be particularly important for tissue repair right on site where the damage occurs, including arteries during the first stages of atherosclerosis. In contrast, the HDL-lipid efflux is relevant for secretory cells where the fusion of intracellular vesicles drastically enlarges the cytoplasmic membrane with the potential consequence of impairment of cell function. In such circumstances, HDL could deliver some functional lipids and pick up not only cholesterol but an integral part of the membrane in excess, restoring the viability of the secretory cells. This hypothesis is congruent with the beneficial effects of HDL against atherosclerosis as well as with their capacity to induce insulin secretion and merits experimental exploration.

The Role of High-Density Lipoprotein Cholesterol in 2022

PURPOSE OF THE REVIEW

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

RECENT FINDINGS

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

Revealing the Impact of Mitochondrial Fitness During Early Neural Development Using Human Brain Organoids

Mitochondrial homeostasis -including function, morphology, and inter-organelle communication- provides guidance to the intrinsic developmental programs of corticogenesis, while also being responsive to environmental and intercellular signals. Two- and three-dimensional platforms have become useful tools to interrogate the capacity of cells to generate neuronal and glia progeny in a background of metabolic dysregulation, but the mechanistic underpinnings underlying the role of mitochondria during human neurogenesis remain unexplored. Here we provide a concise overview of cortical development and the use of pluripotent stem cell models that have contributed to our understanding of mitochondrial and metabolic regulation of early human brain development. We finally discuss the effects of mitochondrial fitness dysregulation seen under stress conditions such as metabolic dysregulation, absence of developmental apoptosis, and hypoxia; and the avenues of research that can be explored with the use of brain organoids.

Approach to patients with hypertriglyceridemia

Elevated triglyceride levels increase the risk of arteriosclerotic cardiovascular disease (ASCVD) and severely elevated triglyceride levels also increase the risk of triglyceride-induced pancreatitis. Although substantially reducing triglyceride levels will prevent pancreatitis, whether lowering triglycerides per se will reduce CVD risk is unclear. In this review, we outline several principles that will help in deciding who and how to treat patients with elevated triglyceride levels in order to prevent both ASCVD and pancreatitis. Using these principles will help in making decisions regarding the treatment of elevated triglyceride levels.

Efficacy and Safety of K-877 (Pemafibrate), a Selective PPARα Modulator, in European Patients on Statin Therapy

OBJECTIVE

High plasma triglyceride (TG) is an independent risk factor for cardiovascular disease. Fibrates lower TG levels through peroxisome proliferator-activated receptor α (PPARα) agonism. Currently available fibrates, however, have relatively low selectivity for PPARα. The aim of this trial was to assess the safety, tolerability, and efficacy of K-877 (pemafibrate), a selective PPARα modulator, in statin-treated European patients with hypertriglyceridemia.

RESEARCH DESIGN AND METHODS

A total of 408 statin-treated adults were recruited from 68 European sites for this phase 2, randomized, double-blind, placebo-controlled trial. They had fasting TG between 175 and 500 mg/dL and HDL-cholesterol (HDL-C) ≤50 mg/dL for men and ≤55 mg/dL for women. Participants were randomly assigned to receive placebo or one of six pemafibrate regimens: 0.05 mg twice a day, 0.1 mg twice a day, 0.2 mg twice a day, 0.1 mg once daily, 0.2 mg once daily, or 0.4 mg once daily. The primary end points were TG and non-HDL-C level lowering at week 12.

RESULTS

Pemafibrate reduced TG at all doses (adjusted P value <0.001), with the greatest placebo-corrected reduction from baseline to week 12 observed in the 0.2-mg twice a day treatment group (54.4%). Reductions in non-HDL-C did not reach statistical significance. Reductions in TG were associated with improvements in other markers for TG-rich lipoprotein metabolism, including reductions in apoB48, apoCIII, and remnant cholesterol and an increase in HDL-C levels. Pemafibrate increased LDL-cholesterol levels, whereas apoB100 was unchanged. Pemafibrate was safe and well-tolerated, with only minor increases in serum creatinine and homocysteine concentrations.

CONCLUSIONS

Pemafibrate is effective, safe, and well-tolerated for the reduction of TG in European populations with hypertriglyceridemia despite statin treatment.

Bezafibrate Reduces Elevated Hepatic Fumarate in Insulin-Deficient Mice

Glucotoxic metabolites and pathways play a crucial role in diabetic complications, and new treatment options which improve glucotoxicity are highly warranted. In this study, we analyzed bezafibrate (BEZ) treated, streptozotocin (STZ) injected mice, which showed an improved glucose metabolism compared to untreated STZ animals. In order to identify key molecules and pathways which participate in the beneficial effects of BEZ, we studied plasma, skeletal muscle, white adipose tissue (WAT) and liver samples using non-targeted metabolomics (NMR spectroscopy), targeted metabolomics (mass spectrometry), microarrays and mitochondrial enzyme activity measurements, with a particular focus on the liver. The analysis of muscle and WAT demonstrated that STZ treatment elevated inflammatory pathways and reduced insulin signaling and lipid pathways, whereas BEZ decreased inflammatory pathways and increased insulin signaling and lipid pathways, which can partly explain the beneficial effects of BEZ on glucose metabolism. Furthermore, lysophosphatidylcholine levels were lower in the liver and skeletal muscle of STZ mice, which were reverted in BEZ-treated animals. BEZ also improved circulating and hepatic glucose levels as well as lipid profiles. In the liver, BEZ treatment reduced elevated fumarate levels in STZ mice, which was probably due to a decreased expression of urea cycle genes. Since fumarate has been shown to participate in glucotoxic pathways, our data suggests that BEZ treatment attenuates the urea cycle in the liver, decreases fumarate levels and, in turn, ameliorates glucotoxicity and reduces insulin resistance in STZ mice.