The effects of simvastatin treatment on plasma lipid-related biomarkers in men with dyslipidaemia

Atorvastatin for patients with cirrhosis. A randomized, placebo-controlled trial

BACKGROUND

Patients with cirrhosis and portal hypertension face a high risk of complications. Besides their anti-inflammatory and antifibrotic effects, statins may reduce portal pressure and thus the risk of complications and mortality. We aimed to investigate the effects of atorvastatin on hospital admissions, mortality, inflammation, and lipidomics in cirrhosis with portal hypertension.

METHODS

We performed a double-blinded, randomized, placebo-controlled clinical trial among patients with cirrhosis and portal hypertension. Atorvastatin (10-20 mg/d) was administered for 6 months. We measured splanchnic hemodynamics, analyzed inflammatory markers, and performed lipidomics at baseline and after 6 months.

RESULTS

Seventy-eight patients were randomized, with 38 patients allocated to atorvastatin and 40 patients to placebo. Fifty-nine patients completed 6 months of intervention. Comparisons between changes in each group were calculated. Liver-related complications and mortality were similar between the groups. The HVPG and Model for End-stage Liver Disease score did not change between groups (p=0.95 and 0.87, respectively). Atorvastatin decreased 3 of 42 inflammatory markers, CD62-L-selectin, matrix metalloproteinases-2, and TNF-α (p-values: 0.005, 0.011, and 0.023, respectively), while lipidomics was not significantly changed.

CONCLUSIONS

In patients with cirrhosis, atorvastatin was safe to use, but did not reduce mortality, the risk of liver-related complications, or the HVPG. Atorvastatin induced minor anti-inflammatory effects and minor effects on lipids during a 6-month treatment period.

The Cardiac Lipidome in Models of Cardiovascular Disease

Cardiovascular disease (CVD) is the leading cause of death worldwide. There are numerous factors involved in the development of CVD. Among these, lipids have an important role in maintaining the myocardial cell structure as well as cardiac function. Fatty acids (FA) are utilized for energy, but also contribute to the pathogenesis of CVD and heart failure. Advances in mass spectrometry methods have enabled the comprehensive analysis of a plethora of lipid species from a single sample comprised of a heterogeneous population of lipid molecules. Determining cardiac lipid alterations in different models of CVD identifies novel biomarkers as well as reveals molecular mechanisms that underlie disease development and progression. This information could inform the development of novel therapeutics in the treatment of CVD. Herein, we provide a review of recent studies of cardiac lipid profiles in myocardial infarction, obesity, and diabetic and dilated cardiomyopathy models of CVD by methods of mass spectrometry analysis.

Changes in circulating pro-protein convertase subtilisin/kexin type 9 levels - experimental and clinical approaches with lipid-lowering agents

Regulation of pro-protein convertase subtilisin/kexin type 9 (PCSK9) by drugs has led to the development of a still small number of agents with powerful activity on low-density lipoprotein cholesterol levels, associated with a significant reduction of cardiovascular events in patients in secondary prevention. The Further Cardiovascular Outcomes Research with PCSK9 Inhibition in Subjects with Elevated Risk (FOURIER) and Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab (ODYSSEY OUTCOMES) studies, with the two available PCSK9 antagonists, i.e. evolocumab and alirocumab, both reported a 15% reduction in major adverse cardiovascular events. Regulation of PCSK9 expression is dependent upon a number of factors, partly genetic and partly associated to a complex transcriptional system, mainly controlled by sterol regulatory element binding proteins. PCSK9 is further regulated by concomitant drug treatments, particularly by statins, enhancing PCSK9 secretion but decreasing its stimulatory phosphorylated form (S688). These complex transcriptional mechanisms lead to variable circulating levels making clinical measurements of plasma PCSK9 for cardiovascular risk assessment a debated matter. Determination of total PCSK9 levels may provide a diagnostic tool for explaining an apparent resistance to PCSK9 inhibitors, thus indicating the need for other approaches. Newer agents targeting PCSK9 are in clinical development with a major interest in those with a longer duration of action, e.g. RNA silencing, allowing optimal patient compliance. Interest has been expanded to areas not only limited to low-density lipoprotein cholesterol reduction but also investigating other non-lipid pathways raising cardiovascular risk, in particular inflammation associated to raised high-sensitivity C-reactive protein levels, not significantly affected by the present PCSK9 antagonists.

Serum Triglyceride Lipase Concentrations are Independent Risk Factors for Coronary Artery Disease and In-Stent Restenosis

Aim: Endothelial lipase (EL), hepatic lipase (HL), and lipoprotein lipase (LPL) are all triglyceride lipases and are associated with coronary artery disease (CAD). However, whether they can be simultaneous independent risk factors for CAD is unknown. In the present study, we investigated whether the three lipases can be independent risk factors simultaneously for CAD and whether combining these lipases could provide greater predictive power than high-density lipoprotein cholesterol (HDL-c) for the development of CAD.

Methods: Eighty-six patients with CAD and 65 healthy controls were enrolled in the study. Additionally, 38 patients who underwent one-year follow-up angiography after percutaneous coronary intervention with stent implantation were collected to investigate in-stent restenosis. Serum EL, HL, and LPL concentrations were measured and compared with other coronary risk factors.

Results: Serum EL and HL concentrations were both significantly increased in patients with CAD or in-stent restenosis, whereas serum LPL concentration was reduced significantly in patients with CAD. Multivariate logistic regression analysis indicated that the three lipases were simultaneous independent risk factors for CAD. However, only serum EL concentration was considered an independent risk factor for in-stent restenosis. Importantly, the receiver operating characteristic curve showed that the combined measurement of the three lipases displayed better predictive power than HDL-c or any one of the three lipases for CAD.

Conclusions: Serum EL concentration was an independent risk factor for both CAD and in-stent restenosis. Moreover, the combined assessment of serum EL, HL, and LPL concentrations as multiple risk factors provided potent predictive power for CAD.

Effect of carnosine supplementation on the plasma lipidome in overweight and obese adults: a pilot randomised controlled trial

Carnosine has been shown to reduce oxidation and glycation of low density lipoprotein hence improving dyslipidaemia in rodents. The effect of carnosine on human plasma lipidome has thus far not been investigated. We aimed to determine whether carnosine supplementation improves the plasma lipidome in overweight and obese individuals. Lipid analysis was performed by liquid chromatography mass spectrometry in 24 overweight and obese adults: 13 were randomly assigned to 2 g carnosine daily and 11 to placebo, and treated for 12 weeks. Carnosine supplementation maintained trihexosylceramide (0.01 ± 0.19 vs -0.28 ± 0.34 nmol/ml, p = 0.04), phosphatidylcholine (77 ± 167 vs -81 ± 196 nmol/ml, p = 0.01) and free cholesterol (20 ± 80 vs -69 ± 80 nmol/ml, p = 0.006) levels compared to placebo. Trihexosylceramide was inversely related with fasting insulin (r = -0.6, p = 0.002), insulin resistance (r = -0.6, p = 0.003), insulin secretion (r = -0.4, p = 0.05) and serum carnosinase 1 activity (r = -0.3, p = 0.05). Both phosphatidylcholine and free cholesterol did not correlate with any cardiometabolic parameters. Our data suggest that carnosine may have beneficial effects on the plasma lipidome. Future larger clinical trials are needed to confirm this.

The role of plasma lipoprotein lipase, hepatic lipase and GPIHBP1 in the metabolism of remnant lipoproteins and small dense LDL in patients with coronary artery disease

BACKGROUND

The relationship between plasma lipoprotein lipase (LPL), hepatic triglyceride lipase (HTGL), glycosylphosphatidylinositol anchored HDL binding protein1 (GPIHBP1) concentration and the metabolism of remnant lipoproteins (RLP) and small dense LDL (sdLDL) in patients with coronary artery disease (CAD) is not fully elucidated.

METHODS

One hundred patients who underwent coronary angiography were enrolled. The plasma LPL, HTGL and GPIHBP1 concentrations were determined by ELISA. The time dependent changes in those lipases, lipids and lipoproteins were studied at a time-point just before, and 15min, 4h and 24h after heparin administration.

RESULTS

The LPL concentration exhibited a significant positive correlation with HDL-C, and inversely correlated with TG and RLP-C. The HTGL concentration was positively correlated with RLP-C and sdLDL-C. The HTGL ratio of the pre-heparin/post-heparin plasma concentration and sdLDL-C/LDL-C ratio were significantly greater in CAD patients than in non-CAD patients. GPIHBP1 was positively correlated with LPL and inversely correlated with RLP-C and sdLDL-C.

CONCLUSION

The HTGL concentration was positively correlated with RLP-C and sdLDL-C, while LPL and GPIHBP1 were inversely correlated with RLP-C and sdLDL-C. These results suggest that elevated HTGL is associated with increased CAD risk, while elevated LPL is associated with a reduction of CAD risk.

Applying metabolomics to cardiometabolic intervention studies and trials: past experiences and a roadmap for the future

Metabolomics and lipidomics are emerging methods for detailed phenotyping of small molecules in samples. It is hoped that such data will: (i) enhance baseline prediction of patient response to pharmacotherapies (beneficial or adverse); (ii) reveal changes in metabolites shortly after initiation of therapy that may predict patient response, including adverse effects, before routine biomarkers are altered; and( iii) give new insights into mechanisms of drug action, particularly where the results of a trial of a new agent were unexpected, and thus help future drug development. In these ways, metabolomics could enhance research findings from intervention studies. This narrative review provides an overview of metabolomics and lipidomics in early clinical intervention studies for investigation of mechanisms of drug action and prediction of drug response (both desired and undesired). We highlight early examples from drug intervention studies associated with cardiometabolic disease. Despite the strengths of such studies, particularly the use of state-of-the-art technologies and advanced statistical methods, currently published studies in the metabolomics arena are largely underpowered and should be considered as hypothesis-generating. In order for metabolomics to meaningfully improve stratified medicine approaches to patient treatment, there is a need for higher quality studies, with better exploitation of biobanks from randomized clinical trials i.e. with large sample size, adjudicated outcomes, standardized procedures, validation cohorts, comparison witth routine biochemistry and both active and control/placebo arms. On the basis of this review, and based on our research experience using clinically established biomarkers, we propose steps to more speedily advance this area of research towards potential clinical impact.

Lipidomics Biomarkers of Diet-Induced Hyperlipidemia and Its Treatment with Poria cocos

Hyperlipidemia is a major cause of atherosclerotic cardiovascular disease. Poria cocos (PC) is a medicinal product widely used in Asia. This study was undertaken to define the alterations of lipid metabolites in rats fed a high-fat diet to induce hyperlipidemia and to explore efficacy and mechanism of action of PC in the treatment of diet-induced hyperlipidemia. Plasma samples were then analyzed using UPLC-HDMS. The untreated rats fed a high-fat diet exhibited significant elevation of plasma triglyceride and total and low-density lipoprotein (LDL) cholesterol concentrations. This was associated with marked changes in plasma concentrations of seven fatty acids (palmitic acid, hexadecenoic acid, hexanoylcarnitine, tetracosahexaenoic acid, cervonoyl ethanolamide, 3-hydroxytetradecanoic acid, and 5,6-DHET) and five sterols [cholesterol ester (18:2), cholesterol, hydroxytestosterone, 19-hydroxydeoxycorticosterone, and cholic acid]. These changes represented disorders of biosynthesis and metabolism of the primary bile acids, steroids, and fatty acids and mitochondrial fatty acid elongation pathways in diet-induced hyperlipidemia. Treatment with PC resulted in significant improvements of hyperlipidemia and the associated abnormalities of the lipid metabolites.

Effect of statin therapy on plasma proprotein convertase subtilisin kexin 9 (PCSK9) concentrations: a systematic review and meta-analysis of clinical trials

AIMS

To evaluate the magnitude of the effect of statin therapy on plasma proprotein convertase subtilisin kexin 9 (PCSK9) levels through a systematic review and meta-analysis of clinical trials.

METHODS

A random-effects model (using DerSimonian-Laird method) and the generic inverse variance method were used for quantitative data synthesis. Heterogeneity was quantitatively assessed using the I(2) index. Sensitivity analyses were conducted using the one-study remove approach. Random-effects meta-regression was performed using an unrestricted maximum likelihood method to evaluate the association between statin-induced elevation of plasma PCSK9 concentrations with duration of treatment and magnitude of LDL cholesterol reduction.

RESULTS

A total of 15 clinical trials examining the effects of statin therapy on plasma PCSK9 levels were included. Meta-analysis of data from single-arm statin treatment arms [weighted mean difference (WMD) 40.72 ng/ml, 95% confidence interval (CI) 34.79, 46.65; p < 0.001] and randomized placebo-controlled trials (WMD 22.98 ng/ml, 95% CI 17.95, 28.01; p < 0.001) showed a significant increase in plasma PCSK9 concentrations after statin therapy, irrespective of the type of statin administered in either of the analyses (single-arm or randomized placebo-controlled trial). There was no significant elevation of plasma PCSK9 levels with statin/ezetimibe combination therapy compared with statin monotherapy (WMD 23.14 ng/ml, 95% CI -1.97, 48.25; p = 0.071); however, removal of one study in the meta-analysis yielded a significant result in the sensitivity analysis (WMD 31.41 ng/ml, 95% CI 7.86, 54.97; p = 0.009).

CONCLUSIONS

This meta-analysis suggests that statin therapy causes a significant increase in plasma PCSK9 concentrations.

Lipidomics in vascular health: current perspectives

Identifying the mechanisms that convert a healthy vascular wall to an atherosclerotic wall is of major importance since the consequences may lead to a shortened lifespan. Classical risk factors (age, smoking, obesity, diabetes mellitus, hypertension, and dyslipidemia) may result in the progression of atherosclerotic lesions by processes including inflammation and lipid accumulation. Thus, the evaluation of blood lipids and the full lipid complement produced by cells, organisms, or tissues (lipidomics) is an issue of importance. In this review, we shall describe the recent progress in vascular health research using lipidomic advances. We will begin with an overview of vascular wall biology and lipids, followed by a short analysis of lipidomics. Finally, we shall focus on the clinical implications of lipidomics and studies that have examined lipidomic approaches and vascular health.

Lipidome and transcriptome profiling of pneumolysin intoxication identifies networks involved in statin-conferred protection of airway epithelial cells

Pneumonia remains one of the leading causes of death in both adults and children worldwide. Despite the adoption of a wide variety of therapeutics, the mortality from community-acquired pneumonia has remained relatively constant. Although viral and fungal acute airway infections can result in pneumonia, bacteria are the most common cause of community-acquired pneumonia, with Streptococcus pneumoniae isolated in nearly 50% of cases. Pneumolysin is a cholesterol-dependent cytolysin or pore-forming toxin produced by Streptococcus pneumonia and has been shown to play a critical role in bacterial pathogenesis. Airway epithelium is the initial site of many bacterial contacts and its barrier and mucosal immunity functions are central to infectious lung diseases. In our studies, we have shown that the prior exposure to statins confers significant resistance of airway epithelial cells to the cytotoxicity of pneumolysin. We decided to take this study one step further, assessing changes in both the transcriptome and lipidome of human airway epithelial cells exposed to toxin, statin or both. Our current work provides the first global view in human airway epithelial cells of both the transcriptome and the lipid interactions that result in cellular protection from pneumolysin.

Plasma lipidomics reveal profound perturbation of glycerophospholipids, fatty acids, and sphingolipids in diet-induced hyperlipidemia

Hyperlipidemia is a major risk factor for coronary heart disease and has emerged as an important public health problem. Lipidomics is a powerful technology for assessment of global lipid metabolites in a biological system and for biomarker discovery. In the present study, hyperlipidemia was induced by feeding rats a high fat diet. A sensitive ultra-performance liquid chromatography coupled with quadrupole time-of-flight synapt high-definition mass spectrometry method was used for the analysis of plasma lipids. Orthogonal partial least squares-discriminant analysis, correlation analysis and heatmap analysis were performed to investigate the metabolic changes in rats with diet-induced hyperlipidemia. Potential biomarkers were detected using S-plot and were identified by accurate mass data, isotopic pattern and MS(E) fragments information. Significantly increased total cholesterol, triglycerides and low-density lipoprotein cholesterol as well as decreased high-density lipoprotein cholesterol were observed in diet-induced hyperlipidemic rats. Combined with standard serum biochemical results, significant differences in plasma lipid compounds including eleven glycerophospholipids, six fatty acids, two sphingolipids, one eicosanoid, one sterol lipid and one glycerolipid were observed, highlighting the perturbation of lipid metabolism in diet-induced hyperlipidemia. These findings provide further insights into the lipid profile across a wide range of biochemical pathways in diet-induced hyperlipidemia.

Plasma lipid profiling across species for the identification of optimal animal models of human dyslipidemia

In an attempt to understand the applicability of various animal models to dyslipidemia in humans and to identify improved preclinical models for target discovery and validation for dyslipidemia, we measured comprehensive plasma lipid profiles in 24 models. These included five mouse strains, six other nonprimate species, and four nonhuman primate (NHP) species, and both healthy animals and animals with metabolic disorders. Dyslipidemic humans were assessed by the same measures. Plasma lipoprotein profiles, eight major plasma lipid fractions, and FA compositions within these lipid fractions were compared both qualitatively and quantitatively across the species. Given the importance of statins in decreasing plasma low-density lipoprotein cholesterol for treatment of dyslipidemia in humans, the responses of these measures to simvastatin treatment were also assessed for each species and compared with dyslipidemic humans. NHPs, followed by dog, were the models that demonstrated closest overall match to dyslipidemic humans. For the subset of the dyslipidemic population with high plasma triglyceride levels, the data also pointed to hamster and db/db mouse as representative models for practical use in target validation. Most traditional models, including rabbit, Zucker diabetic fatty rat, and the majority of mouse models, did not demonstrate overall similarity to dyslipidemic humans in this study.