Inflammation alters HDL composition and function: Implications for HDL-raising therapies

Association between Hp infection and serum uric acid to high-density lipoprotein cholesterol ratio in adults

Background

Helicobacter pylori (Hp) infection is one of the major global health problems resulting in multiple system disorders. The serum uric acid to high density lipoprotein cholesterol ratio (UHR) is a novel index of inflammation and metabolism, but its association with the development of Hp infection is still unclear.

Materials and methods

This is a cross-sectional study involving 2,666 participants, using data from the National Health and Nutrition Examination Survey (NHANES) conducted in the United States. The relationship between UHR and Hp infection was evaluated by multivariate logistic regression and sensitivity analysis to enhance the stability of the results.

Results

Among all individuals, 1,165 were Hp positive (43.7%) and 1,501 were Hp negative (56.3%). After adjustment, there was a positive correlation between UHR and Hp infection (OR = 1.15; 95% CI 1.02-1.30; P = 0.020). This association is relatively stable in the subgroup analysis (P > 0.05).

Conclusion

There is a positive correlation between the UHR and the development of Hp infection in our study. This non-invasive indicator can improve the ability to monitor Hp infection and may find alternative therapeutic intervention targets.

Serum HDL and their subfractions are impaired in multisystem inflammatory syndrome in children (MIS-C)

BACKGROUND

Multisystem inflammatory syndrome in children (MIS-C) is a severe post-COVID condition due to a delayed hyperimmune response to SARS-CoV-2. High-density lipoproteins (HDL) are pivotal players in inflammatory and immune modulation through the remodeling of their subfractions.

METHODS

This study aimed to evaluate serum levels of cholesterol, HDL, and HDL subfractions (HDL-SUB) to define their role in the pathogenesis of MIS-C and their potential use as biomarkers of this condition. We analyzed serum cholesterol, HDL and HDL-SUB (by capillary electrophoresis) in relation to serum values of biomarkers of inflammation and endothelial damage (by microfluidic immunoassays) in 48 patients with MIS-C at hospital admission and in 48 age- and sex-matched healthy controls.

RESULTS

Serum cholesterol, as well as HDL, were significantly lower in MIS-C patients than controls. Serum cholesterol was inversely correlated with all biomarkers of inflammation, confirming the impact of cytokines on reverse cholesterol transport, whereas HDL values were inversely correlated with serum biomarkers of endothelial damage, suggesting a role of HDL in endothelial damage in MIS-C patients. Furthermore, we found a remodeling of HDL-SUB with a more pronounced decrease in small HDL that have anti-inflammatory activity.

CONCLUSIONS

These data confirm the severe impairment of reverse cholesterol transport in MIS-C and indicate serum HDL and HDL-SUB as potential useful diagnostic biomarkers of MIS-C.

Understanding the heterogeneity and dysfunction of HDL in chronic kidney disease: insights from recent reviews

Chronic kidney disease (CKD) is a complex disease that affects the global population's health, with dyslipidemia being one of its major complications. High density lipoprotein (HDL) is regarded as the "hero" in the bloodstream due to its role in reverse cholesterol transport, which lowers cholesterol levels in the blood and prevents atherosclerosis. However, in the complex internal environment of CKD, even this "hero" may struggle to perform its beneficial functions and could potentially become harmful. This article reviews HDL heterogeneity, HDL subclasses, functional changes in HDL during the progression of CKD, and the application of HDL in CKD treatment. This review aims to deepen understanding of lipid metabolism abnormalities in CKD patients and provide a basis for new therapeutic strategies.

The Levels of Serum HBV Pre-Genomic RNA and Its Associated Factors Among HBV-Infected Patients: A Retrospective Cohort Study in Hangzhou, Zhejiang, China

Introduction

This study aimed to explore serum HBV pre-genomic RNA (pgRNA) levels and its associated factors among HBV-infected patients in the real world.

Methods

This retrospective cohort study was conducted from May 10, 2023, to January 15, 2024. Univariate logistic analysis for positive serum HBV pgRNA was performed first, and variables with statistical significance were included in a multivariate logistic model. A decreasing trend of serum HBV pgRNA and HBV DNA levels was also detected first by univariate logistic regression and then by multivariate logistic regression.

Results

482 patients were included in our analysis at baseline, and 191 patients were followed up. Multivariate logistic regression revealed that positive HBV DNA (AOR: 2.63, 95% CI: 1.46-4.75, P=0.001), ≥1000 hBsAg (AOR: 2.29, 95% CI: 1.08-4.89, P=0.03), positive HBeAg (AOR: 28.26, 95% CI: 15.2-52.55, P<0.001), and ALP (AOR: 1.01, 95% CI: 1.001-1.02, P=0.03) were positively correlated with positive HBV pgRNA at baseline. Two independent multivariate logistic regression models were constructed for the decreasing trend of serum HBV pgRNA and HBV DNA for the 191 follow-up patients. Results showed that the decreasing trend of HBV pgRNA was positively correlated with positive baseline HBV DNA (AOR: 4.60, 95% CI: 1.84-11.51, P=0.001), baseline HBsAg ≥1000 IU/mL (AOR: 8.74, 95% CI: 1.09-70.10, P=0.04), and HDL (AOR: 5.01, 95% CI: 1.28-19.66, P=0.02). The decreasing trend of HBV DNA was positively correlated with positive baseline HBV pgRNA (AOR: 3.80, 95% CI: 2.00-8.83, P<0.001) and AST (AOR: 1.06, 95% CI: 1.03-1.08, P<0.001).

Conclusion

Our study revealed that HBV DNA, HBsAg, HBeAg, and ALP were significantly correlated with positive HBV pgRNA at baseline. The baseline HBV DNA, HBsAg, and HDL were significantly correlated with decreasing levels of HBV pgRNA. A decreasing trend of HBV DNA significantly correlated with patients' baseline HBV pgRNA and AST.

HDL-based therapeutics: A promising frontier in combating viral and bacterial infections

Low levels of high-density lipoprotein (HDL) and impaired HDL functionality have been consistently associated with increased susceptibility to infection and its serious consequences. This has been attributed to the critical role of HDL in maintaining cellular lipid homeostasis, which is essential for the proper functioning of immune and structural cells. HDL, a multifunctional particle, exerts pleiotropic effects in host defense against pathogens. It functions as a natural nanoparticle, capable of sequestering and neutralizing potentially harmful substances like bacterial lipopolysaccharides. HDL possesses antiviral activity, preventing viruses from entering or fusing with host cells, thereby halting their replication cycle. Understanding the complex relationship between HDL and the immune system may reveal innovative targets for developing new treatments to combat infectious diseases and improve patient outcomes. This review aims to emphasize the role of HDL in influencing the course of bacterial and viral infections and its and its therapeutic potential.

Epidemiology of lipid disturbances in psoriasis: An analysis of trends from 2006 to 2023

INTRODUCTION

A strong link has been established between psoriasis and lipid disturbances; however, no study has systematically examined their global epidemiology.

METHODS

We searched six databases from their inception up to October 1, 2023. Data analysis was conducted using Stata SE 15.1. We performed subgroup, meta-regression, and sensitivity analyses to assess the heterogeneity of the pooled studies.

RESULTS

Our review included 239 studies comprising 15,519,570 participants. The pooled prevalence rate of dyslipidemia among individuals with psoriasis was 38%.

CONCLUSION

Patients with severe psoriasis should undergo screening for lipid abnormalities. This can facilitate the early detection of lipid dysfunction and associated cardiovascular comorbidities.

Pleiotropic functions and clinical importance of circulating HDL-PON1 complex

High density lipoprotein (HDL) functions are mostly mediated through a complex proteome, particularly its enzymes. HDL can provide a scaffold for the assembly of several proteins that affect each other's function. HDL particles, particularly small, dense HDL3, are rich in paraoxonase 1 (PON1), which is an important enzyme in the functionality of HDL, so the antioxidant and antiatherogenic properties of HDL are largely attributed to this enzyme. There is an increasing need to represent a valid, reproducible, and reliable method to assay HDL function in routine clinical laboratories. In this context, HDL-associated proteins may be key players; notably PON1 activity (its arylesterase activity) may be a proper candidate because its decreased activity can be considered an important risk factor for HDL dysfunctionality. Of note, automated methods have been developed for the measurement of serum PON1 activity that facilitates its assay in large sample numbers. Arylesterase activity is proposed as a preferred activity among the different activities of PON1 for its assay in epidemiological studies. The binding of PON1 to HDL is critical for the maintenance of its activity and it appears apolipoprotein A-I plays an important role in HDL-PON1 interaction as well as in the biochemical and enzymatic properties of PON1. The interrelationships between HDL, PON1, and HDL's other components are complex and incompletely understood. The purpose of this review is to discuss biochemical and clinical evidence considering the interactions of PON1 with HDL and the role of this enzyme as an appropriate biomarker for HDL function as well as a potential therapeutic target.

High-Density Lipoprotein Metabolism and Function in Cardiovascular Diseases: What about Aging and Diet Effects?

Cardiovascular diseases (CVDs) have become the leading global cause of mortality, prompting a heightened focus on identifying precise indicators for their assessment and treatment. In this perspective, the plasma levels of HDL have emerged as a pivotal focus, given the demonstrable correlation between plasma levels and cardiovascular events, rendering them a noteworthy biomarker. However, it is crucial to acknowledge that HDLs, while intricate, are not presently a direct therapeutic target, necessitating a more nuanced understanding of their dynamic remodeling throughout their life cycle. HDLs exhibit several anti-atherosclerotic properties that define their functionality. This functionality of HDLs, which is independent of their concentration, may be impaired in certain risk factors for CVD. Moreover, because HDLs are dynamic parameters, in which HDL particles present different atheroprotective properties, it remains difficult to interpret the association between HDL level and CVD risk. Besides the antioxidant and anti-inflammatory activities of HDLs, their capacity to mediate cholesterol efflux, a key metric of HDL functionality, represents the main anti-atherosclerotic property of HDL. In this review, we will discuss the HDL components and HDL structure that may affect their functionality and we will review the mechanism by which HDL mediates cholesterol efflux. We will give a brief examination of the effects of aging and diet on HDL structure and function.

Serum apolipoprotein B to apolipoprotein A-I ratio predicts mortality in patients with heart failure

AIMS

Apolipoproteins have been reported to be involved in many cardiovascular diseases. The aim of our study was to investigate the prognostic value of apolipoprotein B (ApoB) to apolipoprotein A-I (ApoA-I) ratio (ApoB/ApoA-I) in patients with heart failure (HF).

METHODS AND RESULTS

We randomly assigned 2400 HF patients into the training cohort (n = 1400) and the validation cohort (n = 1000). Using a receiver operating characteristic curve, we identified the optimal cut-off value of the ApoB/ApoA-I in the training cohort as 0.69, which was further validated in the validation cohort. A propensity score matching (PSM) analysis was conducted to eliminate the imbalance in the baseline characteristics of the high and low ApoB/ApoA-I group. A total of 2242 HF patients were generated in the PSM cohort. We also validated our results with an independent cohort (n = 838). Univariate and multivariate analyses were conducted to explore the independent prognostic value of ApoB/ApoA-I in the training cohort (n = 1400), the validation cohort (n = 1000), the PSM cohort (n = 2242), and the independent cohort (n = 838). Patients with high ApoB/ApoA-I ratio had significantly poorer prognosis compared with those with low ApoB/ApoA-I ratio in the training cohort, the validation cohort, the PSM cohort, and the independent cohort (P < 0.05). Multivariate analysis indicated that the ApoB/ApoA-I was an independent prognostic factor for HF in the training cohort [hazard ratio (HR) = 1.637, 95% confidence interval (CI) = 1.201-2.231, P = 0.002], the validation cohort (HR = 1.54, 95% CI = 1.051-2.257, P = 0.027), the PSM cohort (HR = 1.645, 95% CI = 1.273-2.125, P < 0.001), and the independent cohort (HR = 1.987, 95% CI = 1.251-3.155, P = 0.004).

CONCLUSIONS

Serum ApoB/ApoA-I ratio is an independent predictor for the prognosis of HF patients.

High-Density Lipoprotein Particles and Torque Teno Virus in Stable Outpatient Kidney Transplant Recipients

Torque teno virus (TTV) is emerging as a potential marker for monitoring immune status. In transplant recipients who are immunosuppressed, higher TTV DNA loads are observed than in healthy individuals. TTV load measurement may aid in optimizing immunosuppressive medication dosing in solid organ transplant recipients. Additionally, there is a growing interest in the role of HDL particles in immune function; therefore, assessment of both HDL concentrations and TTV load may be of interest in transplant recipients. The objective of this study was to analyze TTV loads and HDL parameters in serum samples collected at least one year post-transplantation from 656 stable outpatient kidney transplant recipients (KTRs), enrolled in the TransplantLines Food and Nutrition Cohort (Groningen, the Netherlands). Plasma HDL particles and subfractions were measured using nuclear magnetic resonance spectroscopy. Serum TTV load was measured using a quantitative real-time polymerase chain reaction. Associations between HDL parameters and TTV load were examined using univariable and multivariable linear regression. The median age was 54.6 [IQR: 44.6 to 63.1] years, 43.3% were female, the mean eGFR was 52.5 (±20.6) mL/min/1.73 m2 and the median allograft vintage was 5.4 [IQR: 2.0 to 12.0] years. A total of 539 participants (82.2%) had a detectable TTV load with a mean TTV load of 3.04 (±1.53) log10 copies/mL, the mean total HDL particle concentration was 19.7 (±3.4) μmol/L, and the mean HDL size was 9.1 (±0.5) nm. The univariable linear regression revealed a negative association between total HDL particle concentration and TTV load (st.β = -0.17, 95% CI st.β: -0.26 to -0.09, p < 0.001). An effect modification of smoking behavior influencing the association between HDL particle concentration and TTV load was observed (Pinteraction = 0.024). After adjustment for age, sex, alcohol intake, hemoglobin, eGFR, donor age, allograft vintage and the use of calcineurin inhibitors, the negative association between HDL particle concentration and TTV load remained statistically significant in the non-smoking population (st.β = -0.14, 95% CI st.β: -0.23 to -0.04, p = 0.006). Furthermore, an association between small HDL particle concentration and TTV load was found (st.β = -0.12, 95% CI st.β: -0.22 to -0.02, p = 0.017). Higher HDL particle concentrations were associated with a lower TTV load in kidney transplant recipients, potentially indicative of a higher immune function. Interventional studies are needed to provide causal evidence on the effects of HDL on the immune system.

Causal association of lipoprotein-associated phospholipids on the risk of sepsis: a Mendelian randomization study

Background

Many previous studies have revealed a close relationship between lipoprotein metabolism and sepsis, but their causal relationship has, until now, remained unclear. Therefore, we performed a two-sample Mendelian randomization analysis to estimate the causal relationship of lipoprotein-associated phospholipids with the risk of sepsis.

Materials and methods

A two-sample Mendelian randomization (MR) analysis was performed to investigate the causal relationship between lipoprotein-associated phospholipids and sepsis based on large-scale genome-wide association study (GWAS) summary statistics. MR analysis was performed using a variety of methods, including inverse variance weighted as the primary method, MR Egger, weighted median, simple mode, and weighted mode as complementary methods. Further sensitivity analyses were used to test the robustness of the data.

Results

After Bonferroni correction, the results of the MR analysis showed that phospholipids in medium high-density lipoprotein (HDL; ORIVW = 0.82, 95% CI 0.71-0.95, P = 0.0075), large HDL (ORIVW = 0.92, 95% CI 0.85-0.98, P = 0.0148), and very large HDL (ORMR Egger = 0.83, 95% CI 0.72-0.95, P = 0.0134) had suggestive causal relationship associations with sepsis. Sensitivity testing confirmed the accuracy of these findings. There was no clear association between other lipoprotein-associated phospholipids and sepsis risk.

Conclusions

Our MR analysis data suggestively showed a correlation between higher levels of HDL-associated phospholipids and reduced risk of sepsis. Further studies are required to determine the underlying mechanisms behind this relationship.

Associations of Serum Uric Acid to High-Density Lipoprotein Cholesterol Ratio with Trunk Fat Mass and Visceral Fat Accumulation

Background

It has been reported recently that the ratio of uric acid to high-density lipoprotein cholesterol (UHR) is correlated with several metabolic disorders. The present study aimed to investigate the associations of UHR with body fat content and distribution.

Methods

This study enrolled 300 participants (58 men and 242 women) aged 18 to 65 years. The levels of serum uric acid and high-density lipoprotein cholesterol were measured by standard enzymatic methods. The overall fat content and segmental fat distribution were assessed with an automatic bioelectrical impedance analyzer. In the population with obesity, the visceral fat area (VFA) and subcutaneous fat area (SFA) were measured using magnetic resonance imaging.

Results

Among the study population, 219 individuals (73.0%) were with obesity. The median level of UHR in individuals with obesity was 33.7% (26.2% - 45.9%), which was significantly higher than that in those without obesity [22.6% (17.0% - 34.4%), P < 0.01]. UHR was positively associated with overall fat content and segmental fat distribution parameters (all P < 0.01). In multivariate linear regression analysis, compared with body mass index, waist circumference was more closely associated with UHR (standardized β = 0.427, P < 0.001) after adjusting for confounding factors. Additionally, total fat mass (standardized β = 0.225, P = 0.002) and trunk fat mass (standardized β = 0.296, P = 0.036) were more closely linked to UHR than total fat-free mass and leg fat mass, respectively. In the population with obesity, VFA was independently correlated with UHR (P < 0.01), while SFA was not associated with UHR.

Conclusion

UHR was significantly associated with overall fat content and trunk fat accumulation. In the population with obesity, UHR was positively associated with VFA. Attention should be paid to the role of excessive trunk fat mass in the relationship between UHR and metabolic disorders.

Mechanistic insights into the anti-restenotic effects of HSP27 and HO1 modulated by reconstituted HDL on neointimal hyperplasia

High-density lipoprotein (HDL) therapy has demonstrated beneficial effects in acute stroke and acute myocardial infarction models by reducing infarct size. In this study, we investigated the inhibitory effects of reconstituted HDL (rHDL) on neointimal hyperplasia and elucidated its underlying mechanism using a balloon injury rat model. Our finding revealed a significant 37% reduction in the intima to media ratio in the arteries treated with 80 mg/kg rHDL compared to those subjected to injury alone (p < 0.05), indicating a specific inhibition of neointimal hyperplasia. In vivo analysis further supported the positive effects of rHDL by demonstrating a reduction in smooth muscle cell (SMC) proliferation and an increase in endothelial cell (EC) proliferation. Additionally, rHDL treatment led to decreased infiltration of leukocytes and downregulated the expression of matrix metallopeptidase 9 (MMP9) in the neointimal area. Notably, rHDL administration resulted in decreased expression of VCAM1 and HIF1α, alongside increased expression of heme oxygenase 1 (HO1) and heat shock protein 27 (HSP27). Overexpression of HSP27 and HO1 effectively inhibited SMC proliferation. Moreover, rHDL-mediated suppression of injury-induced HIF1α coincided with upregulation of HSP27. Interestingly, HSP27 and HO1 had varying effects on the expression of chemokine receptors and rHDL did not exert significant effect on chemokine receptor expression in THP1 cells. These findings underscore the distinct roles of HSP27 and HO1 as potential regulatory factors in the progression of restenosis. Collectively, our study demonstrates that rHDL exerts a potent anti-neointimal hyperplasia effect by reducing leukocytes infiltration and SMC proliferation while promoting EC proliferation.

HDL-Related Parameters and COVID-19 Mortality: The Importance of HDL Function

COVID-19, caused by the SARS-CoV-2 coronavirus, emerged as a global pandemic in late 2019, resulting in significant global public health challenges. The emerging evidence suggests that diminished high-density lipoprotein (HDL) cholesterol levels are associated with the severity of COVID-19, beyond inflammation and oxidative stress. Here, we used nuclear magnetic resonance spectroscopy to compare the lipoprotein and metabolic profiles of COVID-19-infected patients with non-COVID-19 pneumonia. We compared the control group and the COVID-19 group using inflammatory markers to ensure that the differences in lipoprotein levels were due to COVID-19 infection. Our analyses revealed supramolecular phospholipid composite (SPC), phenylalanine, and HDL-related parameters as key discriminators between COVID-19-positive and non-COVID-19 pneumonia patients. More specifically, the levels of HDL parameters, including apolipoprotein A-I (ApoA-I), ApoA-II, HDL cholesterol, and HDL phospholipids, were significantly different. These findings underscore the potential impact of HDL-related factors in patients with COVID-19. Significantly, among the HDL-related metrics, the cholesterol efflux capacity (CEC) displayed the strongest negative association with COVID-19 mortality. CEC is a measure of how well HDL removes cholesterol from cells, which may affect the way SARS-CoV-2 enters cells. In summary, this study validates previously established markers of COVID-19 infection and further highlights the potential significance of HDL functionality in the context of COVID-19 mortality.

Baseline Severity and Inflammation Would Influence the Effect of Simvastatin on Clinical Outcomes in Cirrhosis Patients

BACKGROUND

Simvastatin administration to decompensated cirrhosis patients improved Child-Pugh (CP) at the end of a safety trial (EST).

AIM

To evaluate whether simvastatin reduces cirrhosis severity through a secondary analysis of the safety trial.

METHODS

Thirty patients CP class (CPc) CPc A (n = 6), CPc B (n = 22), and CPc C (n = 2) received simvastatin for one year.

PRIMARY ENDPOINT

cirrhosis severity. Secondary endpoints: health-related quality of life (HRQoL) and hospitalizations for cirrhosis complications.

RESULTS

Cirrhosis severity decreased baseline versus EST only across CP score (7.3 ± 1.3 versus 6.7 ± 1.7, P = 0.041), and CPc: 12 patients lessened from CPc B to CPc A, and three patients increased from CPc A to CPc B (P = 0.029). Due to cirrhosis severity changes and differences in clinical outcomes, 15 patients completed the trial as CPc A_EST and another 15 as CPc B/C. At baseline, CPc A_EST showed greater albumin and high-density lipoprotein cholesterol concentrations than CPc B/C (P = 0.036 and P = 0.028, respectively). Comparing EST versus baseline, only in CPc A_EST, there was a reduction in white-cell blood (P = 0.012), neutrophils (P = 0.029), monocytes (P = 0.035), and C-reactive protein (P = 0.046); an increase in albumin (P = 0.011); and a recovery in HRQoL (P < 0.030). Finally, admissions for cirrhosis complications decreased in CPc A_EST versus CPc B/C (P = 0.017).

CONCLUSIONS

Simvastatin would reduce cirrhosis severity only in CPc B at baseline in a suitable protein and lipid milieu, possibly due to its anti-inflammatory effects. Furthermore, only in CPc A_EST would improve HRQoL and reduce admissions by cirrhosis complications. However, as these outcomes were not primary endpoints, they require validation.

A Current Update on the Role of HDL-Based Nanomedicine in Targeting Macrophages in Cardiovascular Disease

High-density lipoproteins (HDL) are complex endogenous nanoparticles involved in important functions such as reverse cholesterol transport and immunomodulatory activities, ensuring metabolic homeostasis and vascular health. The ability of HDL to interact with a plethora of immune cells and structural cells places it in the center of numerous disease pathophysiologies. However, inflammatory dysregulation can lead to pathogenic remodeling and post-translational modification of HDL, rendering HDL dysfunctional or even pro-inflammatory. Monocytes and macrophages play a critical role in mediating vascular inflammation, such as in coronary artery disease (CAD). The fact that HDL nanoparticles have potent anti-inflammatory effects on mononuclear phagocytes has opened new avenues for the development of nanotherapeutics to restore vascular integrity. HDL infusion therapies are being developed to improve the physiological functions of HDL and to quantitatively restore or increase the native HDL pool. The components and design of HDL-based nanoparticles have evolved significantly since their initial introduction with highly anticipated results in an ongoing phase III clinical trial in subjects with acute coronary syndrome. The understanding of mechanisms involved in HDL-based synthetic nanotherapeutics is critical to their design, therapeutic potential and effectiveness. In this review, we provide a current update on HDL-ApoA-I mimetic nanotherapeutics, highlighting the scope of treating vascular diseases by targeting monocytes and macrophages.

SARS-CoV-2 induced HDL dysfunction may affect the host's response to and recovery from COVID-19

INTRODUCTION

Covid-19 is linked with the development of cardio-metabolic disorders, including dyslipidemia, dysregulation of high-density lipoprotein (HDL), and low-density lipoprotein (LDL). Furthermore, SARS-Co-2 infection is associated with noteworthy changes in lipid profile, which is suggested as a possible biomarker to support the diagnosis and management of Covid-19.

METHODS

This paper adopts the literature review method to obtain information about how Covid-19 affects high-risk group patients and may cause severe and critical effects due to the development of acute lung injury and acute respiratory distress syndrome. A narrative and comprehensive review is presented.

RESULTS

Reducing HDL in Covid-19 is connected to the disease severity and poor clinical outcomes, suggesting that high HDL serum levels could benefit Covid-19. SARS-CoV-2 binds HDL, and this complex is attached to the co-localized receptors, facilitating viral entry. Therefore, SARS-CoV-2 infection may induce the development of dysfunctional HDL through different mechanisms, including induction of inflammatory and oxidative stress with activation of inflammatory signaling pathways. In turn, the induction of dysfunctional HDL induces the activation of inflammatory signaling pathways and oxidative stress, increasing Covid-19 severity.

CONCLUSIONS

Covid-19 is linked with the development of cardio-metabolic disorders, including dyslipidemia in general and dysregulation of high-density lipoprotein and low-density lipoprotein. Therefore, the present study aimed to overview the causal relationship between dysfunctional high-density lipoprotein and Covid-19.

Structure-based mechanism and inhibition of cholesteryl ester transfer protein

PURPOSE OF REVIEW

Cholesteryl ester transfer proteins (CETP) regulate plasma cholesterol levels by transferring cholesteryl esters (CEs) among lipoproteins. Lipoprotein cholesterol levels correlate with the risk factors for atherosclerotic cardiovascular disease (ASCVD). This article reviews recent research on CETP structure, lipid transfer mechanism, and its inhibition.

RECENT FINDINGS

Genetic deficiency in CETP is associated with a low plasma level of low-density lipoprotein cholesterol (LDL-C) and a profoundly elevated plasma level of high-density lipoprotein cholesterol (HDL-C), which correlates with a lower risk of atherosclerotic cardiovascular disease (ASCVD). However, a very high concentration of HDL-C also correlates with increased ASCVD mortality. Considering that the elevated CETP activity is a major determinant of the atherogenic dyslipidemia, i.e., pro-atherogenic reductions in HDL and LDL particle size, inhibition of CETP emerged as a promising pharmacological target during the past two decades. CETP inhibitors, including torcetrapib, dalcetrapib, evacetrapib, anacetrapib and obicetrapib, were designed and evaluated in phase III clinical trials for the treatment of ASCVD or dyslipidemia. Although these inhibitors increase in plasma HDL-C levels and/or reduce LDL-C levels, the poor efficacy against ASCVD ended interest in CETP as an anti-ASCVD target. Nevertheless, interest in CETP and the molecular mechanism by which it inhibits CE transfer among lipoproteins persisted. Insights into the structural-based CETP-lipoprotein interactions can unravel CETP inhibition machinery, which can hopefully guide the design of more effective CETP inhibitors that combat ASCVD. Individual-molecule 3D structures of CETP bound to lipoproteins provide a model for understanding the mechanism by which CETP mediates lipid transfer and which in turn, guide the rational design of new anti-ASCVD therapeutics.

Preeclampsia Affects Lipid Metabolism and HDL Function in Mothers and Their Offspring

Preeclampsia (PE) is linked to an overall increased cardiovascular risk for both the mother and child. Functional impairment of high-density lipoproteins (HDL) may contribute to the excess cardiovascular risk associated with PE. In this study, we investigated the effects of PE on maternal and neonatal lipid metabolism, and the parameters of HDL composition and function. The study cohort included 32 normotensive pregnant women, 18 women diagnosed with early-onset PE, and 14 women with late-onset PE. In mothers, early- and late-onset PE was associated with atherogenic dyslipidemia, characterized by high plasma triglycerides and low HDL-cholesterol levels. We observed a shift from large HDL to smaller HDL subclasses in early-onset PE, which was associated with an increased plasma antioxidant capacity in mothers. PE was further associated with markedly increased levels of HDL-associated apolipoprotein (apo) C-II in mothers, and linked to the triglyceride content of HDL. In neonates of early-onset PE, total cholesterol levels were increased, whereas HDL cholesterol efflux capacity was markedly reduced in neonates from late-onset PE. In conclusion, early- and late-onset PE profoundly affect maternal lipid metabolism, potentially contributing to disease manifestation and increased cardiovascular risk later in life. PE is also associated with changes in neonatal HDL composition and function, demonstrating that complications of pregnancy affect neonatal lipoprotein metabolism.

Low high-density lipoprotein cholesterol levels predicting poor outcomes in patients with hepatitis B virus-related acute-on-chronic liver failure

Background

Lipid profile disorders frequently occur in patients with advanced liver diseases. High-density lipoprotein cholesterol (HDL-C) levels decrease rapidly during acute conditions of some diseases, and HDL-C levels may be related to mortality in patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF).

Materials and methods

A retrospective cohort study was conducted on 200 subjects with HBV-ACLF. The patients were separated into non-survivors and survivors according to their 28-day outcome. Univariate and multivariate Cox regression analyses were performed to identify predictors of mortality, and the performance of these predictors was evaluated by receiver operating characteristic (ROC) curve analysis. Kaplan-Meier analysis was performed to draw survival curves of HDL-C.

Results

The 28-day mortality in the cohort was 27.0%. HDL-C levels differed markedly between non-survivors and survivors. In the multivariate analysis, HDL-C, the Child-Turcotte-Pugh (CTP), model for end-stage liver disease (MELD), and Chinese Group on the Study of Severe Hepatitis B-ACLF II (COSSH-ACLF II) scores were identified as independent predictors for mortality (HR = 0.806, 95% CI: 0.724-0.898; HR = 1.424, 95% CI: 1.143-1.775; HR = 1.006, 95% CI: 1.002-1.007; and HR = 1.609, 95% CI: 1.005-2.575, respectively). Patients with lower HDL-C levels had a worse prognosis than those with higher HDL-C levels. In ROC analysis, the prognostic accuracy for mortality was similar between HDL-C (AUROC: 0.733) and the CTP, MELD, and COSSH-ACLF II scores (AUROC: 0.753; 0.674 and 0.770, respectively).

Conclusion

The HDL-C level may serve as a potential indicator for the prognosis of HBV-ACLF and can be used as a simple marker for risk assessment and selection of therapeutic options.

Lycopene-rich diets modulate HDL functionality and associated inflammatory markers without affecting lipoprotein size and distribution in moderately overweight, disease-free, middle-aged adults: A randomized controlled trial

Background

The consumption of lycopene-rich foods may lower cardiovascular disease (CVD) risk. Lycopene circulates in the blood bound to lipoproteins, including high-density lipoproteins (HDLs). Preliminary data from our group showed that increased consumption of tomato-based food or lycopene supplement in middle-aged subjects led to functional changes to HDL's sub-fractions, HDL₂ and HDL₃. These changes were also associated with a decrease in serum amyloid A (SAA), potentially enhancing their anti-atherogenic properties.

Objective

We carried out a comprehensive randomized controlled intervention trial with healthy middle-aged volunteers to assess whether the consumption of tomato-based foods or lycopene supplements affects HDL functionality and associated inflammatory markers, and lipoprotein subfractions size and distribution.

Design

Volunteers (225, aged 40–65 years) were randomly assigned to one of three dietary intervention groups and asked to consume a control diet (low in tomato-based foods, <10 mg lycopene/week), a lycopene-rich diet (224–350 mg lycopene/week), or the control diet with a lycopene supplement (70 mg lycopene/week). HDL₂ and HDL₃ were isolated by ultracentrifugation. Compliance was monitored by assessing lycopene concentration in serum. Systemic and HDL-associated inflammation was assessed by measuring SAA concentrations. HDL functionality was determined by monitoring paraoxonase-1 (PON-1), cholesteryl ester transfer protein (CETP), and lecithin cholesterol acyltransferase (LCAT) activities. The lipoprotein subfractions profile was assessed by NMR.

Results

Lycopene in serum and HDL significantly increased following consumption of both the high tomato diet and lycopene supplement (p ≤ 0.001 for both). Lycopene, either as a tomato-rich food or a supplement, enhanced both serum- and HDL₃-PON-1 activities (p ≤ 0.001 and p = 0.036, respectively), while significantly reducing HDL₃-SAA-related inflammation (p = 0.001). Lycopene supplement also significantly increased HDL₃-LCAT activity (p = 0.05), and reduced the activity of both HDL₂- and HDL₃-CETP (p = 0.005 and p = 0.002, respectively). These changes were not associated with changes in the subclasses distribution for all lipoprotein fractions or the size of lipoprotein subclasses.

Conclusion

Our results showed that dietary lycopene can significantly enhance HDL functionality, without associated changes in particle size and distribution, by modulating the activity of HDL-associated enzymes. Concomitantly, dietary lycopene significantly decreased serum- and HDL₃-associated SAA, confirming that SAA may represent a sensitive inflammatory biomarker to dietary change.

Clinical Trial Register

(https://www.isrctn.com), ISRCTN34203810.

Dengue virus NS1 protein conveys pro-inflammatory signals by docking onto high-density lipoproteins

The dengue virus nonstructural protein 1 (NS1) is a secreted virulence factor that modulates complement, activates immune cells and alters endothelial barriers. The molecular basis of these events remains incompletely understood. Here we describe a functional high affinity complex formed between NS1 and human high-density lipoproteins (HDL). Collapse of the soluble NS1 hexamer upon binding to the lipoprotein particle leads to the anchoring of amphipathic NS1 dimeric subunits into the HDL outer layer. The stable complex can be visualized by electron microscopy as a spherical HDL with rod-shaped NS1 dimers protruding from the surface. We further show that the assembly of NS1-HDL complexes triggers the production of pro-inflammatory cytokines in human primary macrophages while NS1 or HDL alone do not. Finally, we detect NS1 in complex with HDL and low-density lipoprotein (LDL) particles in the plasma of hospitalized dengue patients and observe NS1-apolipoprotein E-positive complexes accumulating overtime. The functional reprogramming of endogenous lipoprotein particles by NS1 as a means to exacerbate systemic inflammation during viral infection provides a new paradigm in dengue pathogenesis.

The determinants of collateral circulation status in patients with chronic cerebral arterial circle occlusion: A STROBE Study

The condition of collateral pathways is an important predictor of stroke prognoses; however the major determinants of collaterals are still unknown. The purpose of this study is to identify potentially determinants for collateral circulation status in patients with chronic occlusion of cerebral arterial circle. All patients with chronic occlusion of either unilateral internal carotid artery or middle cerebral artery M1 or M2 segment, diagnosed by digital subtraction angiography at the neurology department of the First Medical Centre of Chinese PLA General Hospital from January 2015 to December 2017, were retrospectively collected in our sample. After screening according to inclusion and exclusion criteria, the patients' relevant clinical data were collected and analyzed. Collateral circulations were assessed by 2 independent raters using the American society of interventional and therapeutic neuroradiology/society of interventional radiology flow-grading system. Baseline characteristics (n = 163): our sample consists of 116 (71.2%) male and 47 (28.8%) female patients with an average age of 57.5 ± 11.9 years. Cerebral collateral flow was poor in 59 (36.2%) patients. Our univariate analyses showed that poor collateral circulation was associated with lower high-density lipoproteins cholesterol (HDL), elevated homocysteine levels, aging and hyperlipidemia. A multivariate analysis identified HDL, homocysteine levels and ageing as major predictors for collateral circulation status. In the subgroup analysis, the HDL contributed to collateral angiogenesis internal carotid artery occlusion group. In the middle cerebral artery occlusion group, the homocysteine and ageing were related to the poor collateral status. Low HDL, high levels of homocysteine and ageing are identified as possible risk factors for a poor collateral vessel blood flow in patients with chronic anterior circulation occlusion.

Understanding Myeloperoxidase-Induced Damage to HDL Structure and Function in the Vessel Wall: Implications for HDL-Based Therapies

Atherosclerosis is a disease of increased oxidative stress characterized by protein and lipid modifications in the vessel wall. One important oxidative pathway involves reactive intermediates generated by myeloperoxidase (MPO), an enzyme present mainly in neutrophils and monocytes. Tandem MS analysis identified MPO as a component of lesion derived high-density lipoprotein (HDL), showing that the two interact in the arterial wall. MPO modifies apolipoprotein A1 (apoA-I), paraoxonase 1 and certain HDL-associated phospholipids in human atheroma. HDL isolated from atherosclerotic plaques depicts extensive MPO mediated posttranslational modifications, including oxidation of tryptophan, tyrosine and methionine residues, and carbamylation of lysine residues. In addition, HDL associated plasmalogens are targeted by MPO, generating 2-chlorohexadecanal, a pro-inflammatory and endothelial barrier disrupting lipid that suppresses endothelial nitric oxide formation. Lesion derived HDL is predominantly lipid-depleted and cross-linked and exhibits a nearly 90% reduction in lecithin-cholesterol acyltransferase activity and cholesterol efflux capacity. Here we provide a current update of the pathophysiological consequences of MPO-induced changes in the structure and function of HDL and discuss possible therapeutic implications and options. Preclinical studies with a fully functional apoA-I variant with pronounced resistance to oxidative inactivation by MPO-generated oxidants are currently ongoing. Understanding the relationships between pathophysiological processes that affect the molecular composition and function of HDL and associated diseases is central to the future use of HDL in diagnostics, therapy, and ultimately disease management.

CSL112 (Apolipoprotein A-I [Human]) Strongly Enhances Plasma Apoa-I and Cholesterol Efflux Capacity in Post-Acute Myocardial Infarction Patients: A PK/PD Substudy of the AEGIS-I Trial

Introduction:

Cholesterol efflux capacity (CEC) is impaired following acute myocardial infarction (AMI). CSL112 is an intravenous preparation of human plasma-derived apoA-I formulated with phosphatidylcholine (PC). CSL112 is intended to improve CEC and thereby prevent early recurrent cardiovascular events following AMI. AEGIS-I (ApoA-I Event Reducing in Ischemic Syndromes I) was a multicenter, randomized, double-blind, placebo-controlled, dose-ranging phase 2b study, designed to evaluate the hepatic and renal safety of CSL112. Here, we report an analysis of a pharmacokinetic (PK) and pharmacodynamic (PD) substudy of AEGIS-I.

Methods:

AMI patients were stratified by renal function and randomized 3:3:2 to 4, weekly, 2-hour infusions of low- and high-dose (2 g and 6 g) CSL112, or placebo. PK/PD assessments included plasma concentrations of apoA-I and PC, and measures of total and ABCA1-dependent CEC, as well as lipids/lipoproteins including high density lipoprotein cholesterol (HDL-C), non-HDL-C, low density lipoprotein cholesterol (LDL-C), ApoB, and triglycerides. Inflammatory and cardio-metabolic biomarkers were also evaluated.

Results:

The substudy included 63 subjects from AEGIS-I. CSL112 infusions resulted in rapid, dose-dependent increases in baseline corrected apoA-I and PC, which peaked at the end of the infusion (Tmax ≈ 2 hours). Similarly, there was a dose-dependent elevation in both total CEC and ABCA1-mediated CEC. Mild renal impairment did not affect the PK or PD of CSL112. CSL112 administration was also associated with an increase in plasma levels of HDL-C but not non-HDL-C, LDL-C, apoB, or triglycerides. No dose-effects on inflammatory or cardio-metabolic biomarkers were observed.

Conclusion:

Among patients with AMI, impaired CEC was rapidly elevated by CSL112 infusions in a dose-dependent fashion, along with an increase in apoA-I plasma concentrations. Findings from the current sub-study of the AEGIS-I support a potential atheroprotective benefit of CSL112 for AMI patients.

New prognostic factor for hepatitis B virus-related decompensated cirrhosis: Ratio of monocytes to HDL-cholesterol

Aim

Hepatitis B virus‐related decompensated cirrhosis (HBV‐DeCi) has a high mortality rate, and it remains a challenge to predict its outcomes in clinical practice. We aimed to determine the association between monocyte‐to‐HDL‐cholesterol ratio (MHR) and short‐term prognosis in HBV‐DeCi patients.

Methods

A total of 145 HBV‐DeCi patients were enrolled. A multivariate analysis was performed to identify predictors of mortality. The findings were validated by a receiver operating characteristic analysis using the area under the curve (AUC).

Results

A total of 20 (13.8%) patients had died 30 days after admission. MHR was markedly increased in the non‐survivors compared with the survivors. In the multivariate analysis, MHR was identified as an independent risk factor for mortality, with a significant predictive value (AUC = 0.825; sensitivity, 90.0%; specificity, 62.4%).

Conclusions

Elevated MHR is associated with increased mortality rate in HBV‐DeCi patients.

Inflammation Alters Relationship Between High-Density Lipoprotein Cholesterol and Cardiovascular Risk in Patients With Chronic Kidney Disease: Results From KNOW-CKD

Background

The function of high‐density lipoprotein can change from protective to proatherosclerotic under inflammatory conditions. Herein, we studied whether inflammation could modify the relationship between high‐density lipoprotein level and risk of adverse outcomes in patients with chronic kidney disease .

Methods and Results

In total, 1864 patients from the prospective KNOW‐CKD (Korean Cohort Study for Outcome in Patients With Chronic Kidney Disease) were enrolled. The main predictor was high‐density lipoprotein cholesterol (HDL‐C) level. Presence of inflammation was defined by hs‐CRP (high‐sensitivity C‐reactive protein) level of ≥1.0 mg/L. The primary outcome was extended major adverse cardiovascular events. During 9231.2 person‐years of follow‐up, overall incidence of the primary outcome was 15.8 per 1000 person‐years. In multivariable Cox analysis after adjusting for confounders, HDL‐C level was not associated with the primary outcome. There was a significant interaction between the inflammatory status and HDL‐C for risk of extended major adverse cardiovascular events (P=0.003). In patients without inflammation, the hazard ratios (HRs) (95% CIs) for HDL‐C levels <40, 50 to 59, and ≥60 mg/dL were 1.10 (0.50–1.82), 0.95 (0.50–1.82), and 0.42 (0.19–0.95), respectively, compared with HDL‐C of 40 to 49 mg/dL. However, the significant association for HDL‐C ≥60 mg/dL was not seen after Bonferroni correction. In patients with inflammation, we observed a trend toward increased risk of extended major adverse cardiovascular events in higher HDL‐C groups (HRs [95% CIs], 0.73 [0.37–1.43], 1.24 [0.59–2.61], and 1.56 [0.71–3.45], respectively), but without statistical significance.

Conclusions

The association between HDL‐C level and adverse cardiovascular outcomes showed reverse trends based on inflammation status in Korean patients with chronic kidney disease.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01630486.

Association of Low High-Density Lipoprotein Cholesterol Levels with Poor Outcomes in Hepatitis B-Associated Decompensated Cirrhosis Patients

Background

Lipid levels become decreased in cirrhotic patients and are correlated with disease severity. In the present study, we investigated the impact of serum high-density lipoprotein cholesterol (HDL-C) on prognosis in patients with HBV-associated decompensated cirrhosis (HBV-DeCi).

Methods

The medical records of 153 HBV-DeCi patients were analyzed. Patients were separated into survivors and nonsurvivors according to their 30-day survival. Univariate and multivariate analyses were performed to identify predictors of poor outcomes, and the performance of these predictors was evaluated by receiver operating characteristic (ROC) curve analysis.

Results

The 30-day mortality in the cohort was 18.9%. HDL-C levels differed markedly between survivors and nonsurvivors. On multivariate analysis, Model for End-stage Liver Disease (MELD) score and HDL-C level were identified as independent risk factors for mortality in HBV-DeCi patients. In the ROC analyses, the prognostic accuracy for mortality was similar between HDL-C (area under ROC curve: 0.785) and MELD score (area under ROC curve: 0.853).

Conclusions

Low HDL-C level had a significant correlation with mortality in HBV-DeCi patients and can be used as a simple marker for risk assessment and selection of therapeutic options.

Biological anti-psoriatic therapy profoundly affects high-density lipoprotein function

Psoriasis is a common chronic inflammatory skin disease linked to increased cardiovascular risk. Functional impairment of high-density lipoprotein (HDL) may contribute to excessive cardiovascular mortality in psoriasis patients. Anti-cytokine therapies with biologics have been efficiently used for the management of psoriasis, however little data is available on the effects of biologic anti-psoriatic therapies on the composition and functionality of HDL. Blood samples were taken from 17 healthy volunteers and from 27 real-world psoriasis patients at baseline (no therapy with biologics) and after short-term (3 to 6 months) and intermediate-term (1 to 2 years) therapy. The biologics used included anti-interleukin (IL)-12/23p40 (ustekinumab), anti-IL17A (secukinumab) or anti-tumor necrosis factor-α (etanercept or adalimumab) antibodies. We observed that in psoriasis patients at baseline, metrics of HDL function including cholesterol efflux capacity of apolipoprotein B-depleted serum (p = 0.021), paraoxonase (p < 0.001) and lecithin-cholesterol acyltransferase (p < 0.001) activities were impaired, when compared to controls. Unexpectedly, we observed that short- and especially intermediate-term therapy with biologics markedly reduced HDL cholesterol efflux capacity (p < 0.001) and rendered HDL pro-inflammatory (p < 0.001), but increased paraoxonase (p = 0.009) and lecithin-cholesterol acyltransferase (p = 0.019) activities. All biologics caused similar changes in HDL composition, subclass distribution and cholesterol efflux capacity. Our results provide evidence that anti-psoriatic therapy with biologic agents is associated with changes in HDL functionality, particle composition and subclass distribution.

Coronary heart disease risk: Low-density lipoprotein and beyond

Coronary heart disease (CHD) is the leading cause of morbidity and mortality world-wide and has been characterized as a chronic immunoinflammatory, fibroproliferative disease fueled by lipids. Great advances have been made in elucidating the complex mechanistic interactions among risk factors associated with CHD, yielding abundant success towards preventive measures and the development of pharmaceuticals to prevent and treat CHD via attenuation of lipoprotein-mediated risk. However, significant residual risk remains. Several potentially modifiable CHD risk factors ostensibly contributing to this residual risk have since come to the fore, including systemic inflammation, diabetes mellitus, high-density lipoprotein, plasma triglycerides (TG) and remnant lipoproteins (RLP), lipoprotein(a) (Lp[a]), and vascular endothelial dysfunction (ED). Herein, we summarize the body of evidence implicating each of these risk factors in residual CHD risk.

Psoriasis: Comorbidities

Psoriasis has long been known as a disease with many complications, but was attributed to diet and obesity. However, in recent years, psoriasis itself has been recognized as a series of systemic inflammatory diseases, and that the cytokines involved can induce a variety of other diseases. Individuals with psoriasis were also found to have higher incidences of cerebral and cardiovascular diseases and a younger age at death compared to healthy individuals. However, no clear guidelines have been defined regarding how much vascular lesion testing should be performed in patients with psoriasis. In this report, I attempt to unravel the objective data on psoriasis and its complications from various reviews and reports, and introduce the impact of biologics, which are currently the main treatment for psoriasis, on cardiac vascular disease.

Low CETP activity and unique composition of large VLDL and small HDL in women giving birth to small-for-gestational age infants

Cholesteryl ester transfer protein (CETP) regulates high density lipoproteins (HDL)-cholesterol (C) and HDL-C is essential for fetal development. We hypothesized that women giving birth to large-for-gestational-age (LGA) and small-for-gestational age (SGA) infants differed in longitudinal changes in lipoproteins, CETP activity and HDL-C and that placentas from women with higher or lower circulating HDL-C displayed differential expression of mRNAs involved in cholesterol/nutrient transport, insulin signaling, inflammation/ extracellular matrix (ECM) remodeling. Circulating lipids and CETP activity was measured during pregnancy, NMR lipidomics in late pregnancy, and associations with LGA and SGA infants investigated. RNA sequencing was performed in 28 placentas according to higher and lower maternal HDL-C levels. Lipidomics revealed high triglycerides in large VLDL and lipids/cholesterol/cholesteryl esters in small HDL in women giving birth to SGA infants. Placentas from women with higher HDL-C had decreased levels of CETP expression which was associated with mRNAs involved in cholesterol/nutrient transport, insulin signaling and inflammation/ECM remodeling. Both placental and circulating CETP levels were associated with growth of the fetus. Low circulating CETP activity at 36–38 weeks was associated with giving birth to SGA infants. Our findings suggest a link between increased maternal HDL-C levels, low CETP levels both in circulation and placenta, and SGA infants.

Effect of High-Density Lipoprotein from Healthy Subjects and Chronic Kidney Disease Patients on the CD14 Expression on Polymorphonuclear Leukocytes

In uremic patients, high-density lipoprotein (HDL) loses its anti-inflammatory features and can even become pro-inflammatory due to an altered protein composition. In chronic kidney disease (CKD), impaired functions of polymorphonuclear leukocytes (PMNLs) contribute to inflammation and an increased risk of cardiovascular disease. This study investigated the effect of HDL from CKD and hemodialysis (HD) patients on the CD14 expression on PMNLs. HDL was isolated using a one-step density gradient centrifugation. Isolation of PMNLs was carried out by discontinuous Ficoll-Hypaque density gradient centrifugation. CD14 surface expression was quantified by flow cytometry. The activity of the small GTPase Rac1 was determined by means of an activation pull-down assay. HDL increased the CD14 surface expression on PMNLs. This effect was more pronounced for HDL isolated from uremic patients. The acute phase protein serum amyloid A (SAA) caused higher CD14 expression, while SAA as part of an HDL particle did not. Lipid raft disruption with methyl-β-cyclodextrin led to a reduced CD14 expression in the absence and presence of HDL. HDL from healthy subjects but not from HD patients decreased the activity of Rac1. Considering the known anti-inflammatory effects of HDL, the finding that even HDL from healthy subjects increased the CD14 expression was unexpected. The pathophysiological relevance of this result needs further investigation.

Impaired cholesterol efflux capacity in patients with Helicobacter pylori infection and its relation with inflammation

BACKGROUND

Gut microorganisms are associated with atherosclerosis and related cardiovascular disease. Helicobacter pylori (H. pylori) infection is associated with dyslipidemia and inflammation contributing to the progression of atherosclerosis.

OBJECTIVE

Several studies have reported reduced HDL-C levels in H. pylori infected patients, but HDL cholesterol efflux capacity (CEC) as the most important function of HDL has not been evaluated yet.

METHODS

This cross-sectional study was conducted with 44 biopsy confirmed H. pylori patients and 43 controls. ABCA1-mediated, non-ABCA1 and total CEC were measured in ApoB-depleted serum and levels of ApoA-I, ApoB and hsCRP were estimated using ELISA technique.

RESULTS

Total and ABCA1 mediated-CEC were reduced in patients compared to controls, independent of age, sex, body mass index and HDL-C (p < 0.001), while non-ABCA1 CEC indicated no significant change between the groups. In addition, patients showed lower serum levels of ApoA-I but increased levels of hsCRP when compared to controls. Total CEC and ABCA1-mediated CEC positively correlated with ApoA-I and HDL-C, furthermore, ABCA1-mediated CEC as well as ApoA-I inversely correlated with hsCRP.

CONCLUSION

The results of the present study indicate reduced CECs in H. pylori infected patients, especially ABCA1-mediated CEC which is associated with decreased ApoA-I and increased inflammation.

Obesity-Related Changes in High-Density Lipoprotein Metabolism and Function

In obese individuals, atherogenic dyslipidemia is a very common and important factor in the increased risk of cardiovascular disease. Adiposity-associated dyslipidemia is characterized by low high-density lipoprotein cholesterol (HDL-C) levels and an increase in triglyceride-rich lipoproteins. Several factors and mechanisms are involved in lowering HDL-C levels in the obese state and HDL quantity and quality is closely related to adiponectin levels and the bioactive lipid sphingosine-1-phosphate. Recent studies have shown that obesity profoundly alters HDL metabolism, resulting in altered HDL subclass distribution, composition, and function. Importantly, weight loss through gastric bypass surgery and Mediterranean diet, especially when enriched with virgin olive oil, is associated with increased HDL-C levels and significantly improved metrics of HDL function. A thorough understanding of the underlying mechanisms is crucial for a better understanding of the impact of obesity on lipoprotein metabolism and for the development of appropriate therapeutic approaches. The objective of this review article was to summarize the newly identified changes in the metabolism, composition, and function of HDL in obesity and to discuss possible pathophysiological consequences.

Interaction between high-density lipoproteins and inflammation: Function matters more than concentration!

High-density lipoprotein (HDL) plays an important role in lipid metabolism and especially contributes to the reverse cholesterol transport pathway. Over recent years it has become clear that the effect of HDL on immune-modulation is not only dependent on HDL concentration but also and perhaps even more so on HDL function. This review will provide a concise general introduction to HDL followed by an overview of post-translational modifications of HDL and a detailed overview of the role of HDL in inflammatory diseases. The clinical potential of HDL and its main apolipoprotein constituent, apoA-I, is also addressed in this context. Finally, some conclusions and remarks that are important for future HDL-based research and further development of HDL-focused therapies are discussed.

Current Understanding of the Relationship of HDL Composition, Structure and Function to Their Cardioprotective Properties in Chronic Kidney Disease

In the general population, the ability of high-density lipoproteins (HDLs) to promote cholesterol efflux is a predictor of cardiovascular events, independently of HDL cholesterol levels. Although patients with chronic kidney disease (CKD) have a high burden of cardiovascular morbidity and mortality, neither serum levels of HDL cholesterol, nor cholesterol efflux capacity associate with cardiovascular events. Important for the following discussion on the role of HDL in CKD is the notion that traditional atherosclerotic cardiovascular risk factors only partially account for this increased incidence of cardiovascular disease in CKD. As a potential explanation, across the spectrum of cardiovascular disease, the relative contribution of atherosclerotic cardiovascular disease becomes less important with advanced CKD. Impaired renal function directly affects the metabolism, composition and functionality of HDL particles. HDLs themselves are a heterogeneous population of particles with distinct sizes and protein composition, all of them affecting the functionality of HDL. Therefore, a more specific approach investigating the functional and compositional features of HDL subclasses might be a valuable strategy to decipher the potential link between HDL, cardiovascular disease and CKD. This review summarizes the current understanding of the relationship of HDL composition, metabolism and function to their cardio-protective properties in CKD, with a focus on CKD-induced changes in the HDL proteome and reverse cholesterol transport capacity. We also will highlight the gaps in the current knowledge regarding important aspects of HDL biology.

Association Between Serum High-Density Lipoprotein Cholesterol Levels and Progression of Chronic Kidney Disease: Results From the KNOW-CKD

Background High-density lipoprotein cholesterol ( HDL -C) levels are generally decreased in patients with chronic kidney disease ( CKD ). However, studies on the relationship between HDL -C and CKD progression are scarce. Methods and Results We studied the association between serum HDL -C levels and the risk of CKD progression in 2168 participants of the KNOW - CKD (Korean Cohort Study for Outcome in Patients With Chronic Kidney Disease). The primary outcome was the composite of a 50% decline in estimated glomerular filtration rate from baseline or end-stage renal disease. The secondary outcome was the onset of end-stage renal disease. During a median follow-up of 3.1 (interquartile range, 1.6-4.5) years, the primary outcome occurred in 335 patients (15.5%). In a fully adjusted Cox model, the lowest category with HDL -C of <30 mg/dL (hazard ratio, 2.21; 95% CI, 1.30-3.77) and the highest category with HDL -C of ≥60 mg/dL (hazard ratio, 2.05; 95% CI , 1.35-3.10) were associated with a significantly higher risk of the composite renal outcome, compared with the reference category with HDL -C of 50 to 59 mg/dL. This association remained unaltered in a time-varying Cox analysis. In addition, a fully adjusted cubic spline model with HDL -C being treated as a continuous variable yielded similar results. Furthermore, consistent findings were obtained in a secondary outcome analysis for the development of end-stage renal disease. Conclusions A U-shaped association was observed between serum HDL -C levels and adverse renal outcomes in this large cohort of patients with CKD . Our findings suggest that both low and high serum HDL -C levels may be detrimental to patients with nondialysis CKD .

Immune Dysfunction in Uremia 2020

Cardiovascular disease and infections are major causes for the high incidence of morbidity and mortality of patients with chronic kidney disease. Both complications are directly or indirectly associated with disturbed functions or altered apoptotic rates of polymorphonuclear leukocytes, monocytes, lymphocytes, and dendritic cells. Normal responses of immune cells can be reduced, leading to infectious diseases or pre-activated/primed, giving rise to inflammation and subsequently to cardiovascular disease. This review summarizes the impact of kidney dysfunction on the immune system. Renal failure results in disturbed renal metabolic activities with reduced renin, erythropoietin, and vitamin D production, which adversely affects the immune system. Decreased kidney function also leads to reduced glomerular filtration and the retention of uremic toxins. A large number of uremic toxins with detrimental effects on immune cells have been identified. Besides small water-soluble and protein-bound compounds originating from the intestinal microbiome, several molecules in the middle molecular range, e.g., immunoglobulin light chains, retinol-binding protein, the neuropeptides Met-enkephalin and neuropeptide Y, endothelin-1, and the adipokines leptin and resistin, adversely affect immune cells. Posttranslational modifications such as carbamoylation, advanced glycation products, and oxidative modifications contribute to uremic toxicity. Furthermore, high-density lipoprotein from uremic patients has an altered protein profile and thereby loses its anti-inflammatory properties.

Altered composition and functional profile of high-density lipoprotein in leprosy patients

The changes in host lipid metabolism during leprosy have been correlated to fatty acid alterations in serum and with high-density lipoprotein (HDL) dysfunctionality. This is most evident in multibacillary leprosy patients (Mb), who present an accumulation of host lipids in Schwann cells and macrophages. This accumulation in host peripheral tissues should be withdrawn by HDL, but it is unclear why this lipoprotein from Mb patients loses this function. To investigate HDL metabolism changes during the course of leprosy, HDL composition and functionality of Mb, Pb patients (paucibacillary) pre- or post-multidrug therapy (MDT) and HC (healthy controls) were analyzed. Mb pre-MDT patients presented lower levels of HDL-cholesterol compared to HC. Moreover, Ultra Performance Liquid Chromatography-Mass Spectrometry lipidomics of HDL showed an altered lipid profile of Mb pre-MDT compared to HC and Pb patients. In functional tests, HDL from Mb pre-MDT patients showed impaired anti-inflammatory and anti-oxidative stress activities and a lower cholesterol acceptor capacity compared to other groups. Mb pre-MDT showed lower concentrations of ApoA-I (apolipoprotein A-I), the major HDL protein, when compared to HC, with a post-MDT recovery. Changes in ApoA-I expression could also be observed in M. leprae-infected hepatic cells. The presence of bacilli in the liver of a Mb patient, along with cell damage, indicated hepatic involvement during leprosy, which may reflect on ApoA-I expression. Together, altered compositional and functional profiles observed on HDL of Mb patients can explain metabolic and physiological changes observed in Mb leprosy, contributing to a better understanding of its pathogenesis.

The Roles of Lipoprotein in Psoriasis

The association between psoriasis and cardiovascular disease risk has been supported by recent epidemiological data. Patients with psoriasis have an increased adjusted relative risk for myocardial infarction. As such, the cardiovascular risk conferred by severe psoriasis may be comparable to what is seen with other well-established risk factors, such as diabetes mellitus. Previous studies demonstrated that low-density lipoprotein (LDL) plays critical roles during atherogenesis. It may be caused by the accumulation of macrophages and lipoprotein in the vessel wall. Oxidized LDL (ox-LDL) stimulates the expression of adhesion molecules, such as ICAM-1 and VCAM-1, on endothelial cells and increases the attachment of mononuclear cells and the endothelium. Even though previous evidence demonstrated that psoriasis patients have tortuous and dilated blood vessels in the dermis, which results in the leakage of ox-LDL, the leaked ox-LDL may increase the expression of adhesion molecules and cytokines, and disturb the static balance of osmosis. Therefore, exploration of the relationship between hyperlipidemia and psoriasis may be another novel treatment option for psoriasis and may represent the most promising strategy.

Roles of Reconstituted High-Density Lipoprotein Nanoparticles in Cardiovascular Disease: A New Paradigm for Drug Discovery

Epidemiological results revealed that there is an inverse correlation between high-density lipoprotein (HDL) cholesterol levels and risks of atherosclerotic cardiovascular disease (ASCVD). Mounting evidence supports that HDLs are atheroprotective, therefore, many therapeutic approaches have been developed to increase HDL cholesterol (HDL-C) levels. Nevertheless, HDL-raising therapies, such as cholesteryl ester transfer protein (CETP) inhibitors, failed to ameliorate cardiovascular outcomes in clinical trials, thereby casting doubt on the treatment of cardiovascular disease (CVD) by increasing HDL-C levels. Therefore, HDL-targeted interventional studies were shifted to increasing the number of HDL particles capable of promoting ATP-binding cassette transporter A1 (ABCA1)-mediated cholesterol efflux. One such approach was the development of reconstituted HDL (rHDL) particles that promote ABCA1-mediated cholesterol efflux from lipid-enriched macrophages. Here, we explore the manipulation of rHDL nanoparticles as a strategy for the treatment of CVD. In addition, we discuss technological capabilities and the challenge of relating preclinical in vivo mice research to clinical studies. Finally, by drawing lessons from developing rHDL nanoparticles, we also incorporate the viabilities and advantages of the development of a molecular imaging probe with HDL nanoparticles when applied to ASCVD, as well as gaps in technology and knowledge required for putting the HDL-targeted therapeutics into full gear.

The Role and Function of HDL in Patients with Chronic Kidney Disease and the Risk of Cardiovascular Disease

Chronic kidney disease (CKD) is a worldwide health problem with steadily increasing occurrence. Significantly elevated cardiovascular morbidity and mortality have been observed in CKD. Cardiovascular diseases are the most important and frequent cause of death of CKD patients globally. The presence of CKD is related to disturbances in lipoprotein metabolism whose consequences are dyslipidemia and the accumulation of atherogenic particles. CKD not only fuels the reduction of high-density lipoprotein (HDL) cholesterol concentration, but also it modifies the composition of this lipoprotein. The key role of HDL is the participation in reverse cholesterol transport from peripheral tissues to the liver. Moreover, HDL prevents the oxidation of low-density lipoprotein (LDL) cholesterol by reactive oxygen species (ROS) and protects against the adverse effects of oxidized LDL (ox-LDL) on the endothelium. Numerous studies have demonstrated the ability of HDL to promote the production of nitric oxide (NO) by endothelial cells (ECs) and to exert antiapoptotic and anti-inflammatory effects. Increasing evidence suggests that in patients with chronic inflammatory disorders, HDLs may lose important antiatherosclerotic properties and become dysfunctional. So far, no therapeutic strategy to raise HDL, or alter the ratio of HDL subfractions, has been successful in slowing the progression of CKD or reducing cardiovascular disease in patients either with or without CKD.

Prognostic value of the serum apolipoprotein B to apolipoprotein A-I ratio in metastatic colorectal cancer patients

Background: The aim of our research was to assess the prognostic value of the apolipoprotein B (ApoB) to apolipoprotein A-I (ApoA-I) ratio (ApoB/ApoA-I) in metastatic colorectal cancer (mCRC) patients.

Methods: We randomly assigned 838 patients into the training cohort (n=578) and the validation cohort (n=260). The cut-off value of the ApoB/ApoA-I in the training cohort identified by a receiver operating characteristic (ROC) curve was 0.69 and was further validated in the validation cohort. A propensity score matching (PSM) analysis was carried out to eliminate the imbalance in the baseline characteristics of the high and low ApoB/ApoA-I group. The PSM cohort of 542 mCRC patients was generated. We also validated our main findings and conclusions with an independent cohort (n=150). Univariate and multivariate analyses were conducted to explore the independent prognostic value of the ApoB/ApoA-I in the training cohort (n=578), the validation cohort (n=260), the PSM cohort (n=542) and the independent cohort (n=150).

Results: Patients in the high ApoB/ApoA-I group had significantly shorter overall survival compared to those in the low ApoB/ApoA-I group in the training cohort, the validation cohort, the PSM cohort and the independent cohort (P <0.01). Multivariate analysis indicated that the ApoB/ApoA-I was an independent prognostic index for OS in the training cohort [hazard ratio (HR):1.371; 95% confidence interval (CI):1.205-1.870, P=0.045], the validation cohort (HR: 1.924; 95% CI: 1.360-2.723, P<0.001), the PSM cohort (HR: 1.599; 95% CI: 1.287-1.988, P<0.001) and the independent cohort (HR: 1.949; 95% CI: 1.014-3.747, P=0.046).

Conclusions: An increased baseline serum ApoB/ApoA-I is an independent prognostic factor for a poor prognosis in mCRC patients.

Allergic rhinitis is associated with complex alterations in high-density lipoprotein composition and function

Despite strong evidence that high-density lipoproteins (HDLs) modulate the immune response, the role of HDL in allergies is still poorly understood. Many patients with allergic rhinitis (AR) develop a late-phase response, characterized by infiltration of monocytes and eosinophils into the nasal submucosa. Functional impairment of HDL in AR-patients may insufficiently suppress inflammation and cell infiltration, but the effect of AR on the composition and function of HDL is not understood. We used apolipoprotein (apo) B-depleted serum as well as isolated HDL from AR-patients (n = 43) and non-allergic healthy controls (n = 20) for detailed compositional and functional characterization of HDL. Both AR-HDL and apoB-depleted serum of AR-patients showed decreased anti-oxidative capacity and impaired ability to suppress monocyte nuclear factor-κB expression and pro-inflammatory cytokine secretion, such as interleukin (IL)-4, IL-6, IL-8, tumor necrosis factor alpha and IL-1 beta. Sera of AR-patients showed decreased paraoxonase and cholesteryl-ester transfer protein activities, increased lipoprotein-associated phospholipase A2 activity, while lecithin-cholesterol acyltransferase activity and cholesterol efflux capacity were not altered. Surprisingly, apoB-depleted serum and HDL from AR-patients showed an increased ability to suppress eosinophil effector responses upon eotaxin-2/CCL24 stimulation. Mass spectrometry and biochemical analyses showed reduced levels of apoA-I and phosphatidylcholine, but increased levels of apoA-II, triglycerides and lyso-phosphatidylcholine in AR-HDL. The changes in AR-HDL composition were associated with altered functional properties. In conclusion, AR alters HDL composition linked to decreased anti-oxidative and anti-inflammatory properties but improves the ability of HDL to suppress eosinophil effector responses.

Altered proteome of high-density lipoproteins from paediatric acute lymphoblastic leukemia survivors

Acute lymphoblastic leukemia (ALL) is the most frequent malignancy in children. With the use of more modern, efficient treatments, 5-year survival has reached more than 90% in this population. However, this achievement comes with many secondary and long-term effects since more than 65% of the survivors experience at least one severe complication, including the metabolic syndrome and cardiovascular diseases. The main objective of the present work was to characterize the composition of HDL particles isolated from pediatric ALL survivors. HDLs from 8 metabolically healthy ALL survivors, 8 metabolically unhealthy ALL survivors and 8 age- and gender-matched controls were analyzed. The HDL fraction from the survivors contained less cholesterol than the controls. In addition, proteomic analyses revealed an enrichment of pro-thrombotic (e.g., fibrinogen) and pro-inflammatory (e.g., amyloid A) proteins in the HDLs deriving from metabolically unhealthy survivors. These results indicate an alteration in the composition of lipid and protein content of HDL from childhood ALL survivors with metabolic disorders. Although more work is needed to validate the functionality of these HDLs, the data seem relevant for survivor health given the detection of potential biomarkers related to HDL metabolism and functionality in cancer.

High-Density Lipoprotein from Chronic Kidney Disease Patients Modulates Polymorphonuclear Leukocytes

The anti-inflammatory properties of high-density lipoproteins (HDL) are lost in uremia. These HDL may show pro-inflammatory features partially as a result of changed protein composition. Alterations of polymorphonuclear leukocytes (PMNLs) in chronic kidney disease (CKD) may contribute to chronic inflammation and high vascular risk. We investigated if HDL from uremic patients is related to systemic inflammation by interfering with PMNL function. PMNL apoptosis was investigated by assessing morphological features and DNA content. CD11b surface expression was quantified by flow cytometry. Oxidative burst was measured via cytochrome c reduction assay. Chemotaxis was assessed by using an under-agarose migration assay. We found that HDL from CKD and hemodialysis (HD) patients significantly attenuated PMNL apoptosis, whereas HDL isolated from healthy subjects had no effect on PMNL apoptosis. The use of signal transduction inhibitors indicated that uremic HDL exerts anti-apoptotic effects by activating pathways involving phosphoinositide 3-kinase and extracellular-signal regulated kinase. Healthy HDL attenuated the surface expression of CD11b, whereas HDL from CKD and HD patients had no effect. All tested isolates increased the stimulation of oxidative burst, but did not affect PMNL chemotactic movement. In conclusion, HDL may contribute to the systemic inflammation in uremic patients by modulating PMNL functions.