HDL and endothelial protection

Association Between Serum Uric Acid to High-Density Lipoprotein Cholesterol Ratio and Pneumonia After Endovascular Treatment of Vertebrobasilar Artery Occlusion

Background

The uric acid to high-density lipoprotein cholesterol ratio (UHR) is a novel marker of inflammation and metabolism. We aimed to explore the association of UHR with pneumonia after endovascular thrombectomy (EVT) in patients with vertebrobasilar artery occlusion (VBAO).

Methods

We retrospectively enrolled participants diagnosed with acute VBAO treated with EVT within 24 hours of estimated occlusion time from the multicenter PERSIST study. The primary outcome was pneumonia within 7 days after EVT according to the Pneumonia in Stroke Consensus Group recommendations. We utilized the restricted cubic spline curve to explore the dose-response relationship between UHR and pneumonia. We used multivariable logistic regression models to assess the association between UHR and the risk of pneumonia after EVT and verified the findings in subgroup analysis.

Results

Three hundred and seventy-eight patients were enrolled in this study, and 236 (62.4%) were diagnosed with pneumonia. In multivariable models, a higher UHR was associated with an increased risk of pneumonia after EVT (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.01-1.10; P = 0.020; tertile 3 versus tertile 1: OR, 2.09; 95% CI, 1.15-3.82; P = 0.016). The dose-response relationship indicated that UHR was linearly associated with the risk of pneumonia (P = 0.888). The association between UHR and pneumonia remained significant in different subgroups.

Conclusion

This study demonstrated that a higher UHR was associated with an increased risk of pneumonia in VABO patients treated with EVT. Further studies were warranted to verify the prognostic values of UHR in pneumonia after EVT.

Establishing and internally validating a predictive model for coronary heart disease incorporating triglyceride-glucose index, monocyte-to-high-density lipoprotein cholesterol ratio and conventional risk factors in patients experiencing chest pain and referred for invasive coronary angiography

BACKGROUND

Coronary heart disease (CHD) represents a severe form of ischemic cardiac condition that necessitates timely and accurate diagnosis. Although coronary angiography (CAG) remains widely used to detect CHD, healthcare facilities, medical expenses, and equipment technology often limit its availability. Therefore, it is imperative to identify a non-invasive diagnostic approach with high accuracy for CHD.

METHODS

This cross-sectional research included patients with chest pain (≥ 18 years) hospitalized at Chengde Central Hospital between September 2020 and March 2024. Among the participants, 70% were split into the training, and 30% were randomly entered into the validation sets. In the training dataset, univariate and multivariate logistic regression analyses were rigorously employed to ascertain predictors of CHD. A model was formulated by incorporating these predictors in a nomogram, which was evaluated for accuracy using calibration curves. The model's discrimination was quantified by calculating the area under the receiver operating characteristic (ROC) curve, denoted as the area under the curve (AUC), and its clinical application value was determined through decision curve analysis (DCA). Finally, we compare our model against the pretest probability (PTP) calculated by the Update Diamond-Forrester Model (UDFM) as recommended by the ECS guidelines to comprehensively assess its performance.

RESULTS

This study included 1501 patients who presented with chest pain, with a mean age of 60.45 years, 865 males (57.60%). Multivariate logistic regression analysis revealed TyG index, MHR, male, age, diabetes, systolic blood pressure (SBP), regional wall motion abnormality (RWMA), ST-T changes, and low-density lipoprotein cholesterol (LDL-C) as independent predictors of CHD. A novel nomogram incorporating these independent risk factors exhibited high accuracy and perfect consistency, with a training set AUC calculated to be 0.733 (95% CI: 0.698-0.768), and the validation set maintained a strong performance at 0.721 (95% CI: 0.663-0.779). The calibration curves and the Hosmer-Lemeshow test confirmed the well-fitting model (P = 0.576 and P = 0.694). ROC curve analysis and DCA demonstrated that the model has robust forecasting capability.

CONCLUSION

The nomogram model in this study exhibited good discriminative ability, calibration, and a favorable net benefit. Its predictive performance exceeds that of the traditional PTP tool and may serve as a non-invasive and promising approach to aid clinicians in the early identification of CHD risk in patients presenting with chest pain.

Production, characterization and biodistribution of therapeutic high-density lipoprotein-like nanoparticles reconstituted with or without histidine-tagged recombinant ApoA1

High-density lipoproteins (HDLs) are known for their cardiovascular protection due to apolipoprotein A-1 (ApoA1), their primary protein. ApoA1 promotes cholesterol reverse transport and exhibits antioxidant and anti-inflammatory properties. Although increasing HDL levels has not consistently reduced cardiovascular mortality in clinical trials, reconstituted HDL (rHDL) nanoparticles containing ApoA1 show potential in treating acute inflammation, such as in ischemic stroke, sepsis, and even COVID-19. ApoA1 is commonly produced in bacteria due to its simplicity and potential therapeutic optimisation. Addition of a histidine tag to recombinant ApoA1 may improve purification, stability and therapeutic efficacy, although its functional impact remains a subject of debate. In this study, ApoA1 with a poly-histidine tag (His-rApoA1) was produced in a clear coli system for simplified purification, followed by an evaluation of the tag's effects on rHDL nanoparticle properties. rHDL and His-rHDL nanoparticles were prepared using the sodium cholate dialysis method, combining recombinant rApoA1 or His-rApoA1 with phosphatidylcholine at a 1:75 M ratio. Nuclear magnetic resonance confirmed that both forms of rApoA1 structurally resembled plasma ApoA1, whether lipid-free or in nanoparticle form. Dynamic light scattering and electron microscopy revealed nanoparticle sizes around 7 nm with native HDL-like morphology. Testing on endothelial cells (EA.hy926) showed rapid uptake of rHDL and His-rHDL while preserving cell viability. Additionally, both nanoparticles reduced interleukin-6 and ICAM-1 expression in cells, demonstrating their anti-inflammatory and protective effects, unaffected by the poly-histidine tag. Intravenous injection in mice shows homogeneous distribution of His-rHDL in the liver, lungs, and spleen, with no cytotoxicity, indicating potential use for treating inflammatory diseases.

HDL proteome and apolipoproteins concentrations in severe ICU COVID-19 patients

BACKGROUND

SARS-CoV-2 infection affects both lipid metabolism and lung function. The severity of the disease has been associated with reduced levels of both high-density lipoprotein (HDL) and low-density lipoprotein cholesterol. Despite the crucial role that these nanoparticles play in SARS-CoV-2 infection, few studies have examined their structure during COVID-19 beyond HDL quantity. The study aimed to assess apolipoprotein levels in COVID-19 patients who either survived or died following ICU admission. In addition, ICU survivors and non-survivors were compared for HDL particle size and proteome.

METHODS

Between February and April 2020, our study enrolled 37 COVID-19 patients upon their intensive care unit admission. Among them, 18 survived the disease, while 19 succumbed to it. We used mass spectrometry to assess plasma levels of 14 apolipoproteins and LCAT. Additionally, we analyzed HDL subpopulation distribution by utilizing native polyacrylamide gel electrophoresis. HDL particles were isolated from both surviving and non-surviving patients using ultracentrifugation, followed by characterization of their proteomes with NanoLC-MS/MS.

RESULTS

Plasma apolipoproteins, including Apo A-II, Apo Cs (I, II, III), Apo H, Apo J, Apo M, and LCAT, were decreased in patients who did not survive COVID-19. However, no alterations were noted in the distribution of HDL subpopulations in relation to mortality. HDL composition was further altered based on mortality, displaying a decline in Apo H and paraoxonase 3.

CONCLUSION

In conclusion, we have shown an alteration in plasma apolipoproteins and HDL composition between surviving COVID-19 patients and non-survivors. Some markers, such as Apo H, are more predictive than baseline lipid concentrations such as HDL-C. These markers appear to provide a more accurate indication of mortality during COVID-19 compared with baseline lipid concentrations such as HDL-C.

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.

The compensatory enrichment of sphingosine-1-phosphate on HDL in FSGS enhances the protective function of glomerular endothelial cells compared to MCD

Glomerular endothelial cells (GECs) are pivotal in developing glomerular sclerosis disorders. The advancement of focal segmental glomerulosclerosis (FSGS) is intimately tied to disruptions in lipid metabolism. Sphingosine-1-phosphate (S1P), a molecule transported by high-density lipoproteins (HDL), exhibits protective effects on vascular endothelial cells by upregulating phosphorylated endothelial nitric oxide synthase (p-eNOS) and enhancing nitric oxide (NO) production. Nevertheless, the abundance of S1P within HDL in individuals with FSGS and minimal change disease (MCD) is yet to be elucidated, and its defensive role in GECs necessitates empirical confirmation. A total of 14 FSGS patients, 16 MCD patients, and 16 healthy controls (NC) were included in the study, with FSGS and MCD confirmed by renal biopsy. After blood sample collection, HDL was isolated and categorized into intact HDL, phospholipid-depleted HDL(apo-HDL), phospholipid-remained HDL(phoHDL), and recombinant HDL (rHDL). Various HDL samples, comprising intact, apo-HDL, pho-HDL and rHDL, were co-cultivated with human renal glomerular endothelial cells (HRGECs). Western blotting was utilized to quantify p-eNOS levels and assess PI3K-AKT pathway activation. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyzed S1P concentrations, while real-time quantitative PCR evaluated the expression of enzymes involved in S1P metabolism. Fluorescence labeling methods measured NO levels, and an immunofluorescence colocalization assay investigated Sphingosine-1-phosphate receptor 1 (S1PR1) expression in GECs across distinct kidney tissue groups. The HDL from FSGS patients demonstrated a significantly enhanced ability to promote p-eNOS expression and NO release in HRGECs compared to MCD patients and healthy controls. Additionally, the synthesis activity of S1P in renal tissues of FSGS patients was markedly higher than that observed in MCD patients and healthy controls, suggesting that S1P may play a crucial protective role in the progression of FSGS. Immunofluorescence staining showed that compared with MCD and NC, the expression of S1PR1 in GECs of FSGS patients was significantly decreased. Recombinant HDL with added S1P promoted the increase of p-eNOS in HRGECs. Knockdown of S1PR1 using siRNA reduced the expression of p-eNOS and NO release. The mechanism underlying the regulation of p-eNOS expression by rHDL was associated with the PI3K-AKT signaling pathway. The enhanced presence of S1P on HDL could serve as a diagnostic marker to differentiate FSGS from MCD. Incorporating S1P into HDL enhances glomerular endothelial cell function, suggesting that the S1P/S1PR pathway might offer a promising therapeutic avenue for FSGS.

Lipoprotection in cardiovascular diseases

Cardioprotection is a well-established term in the scientific world. It describes the protection of various mediators on the cardiovascular system. These protective effects can also be provided by certain lipids. Since lipids are a very specific and clearly definable class of substances, we define the term lipoprotection as lipid-mediated cardioprotection. In this review, we highlight high-density lipoprotein (HDL), sphingosine-1-phosphate (S1P) and omega-3 polyunsaturated fatty acids (n-3 PUFA) as the most important lipoprotective mediators and show their beneficial impact on coronary artery disease (CAD), acute myocardial infarction (AMI) and heart failure (HF).

A Pilot Study of the Total Cholesterol/High-Density Lipoprotein Ratio as a Prognostic Indicator of Hyperlipidemia-Related Diseases in Dogs and Cats

In veterinary medicine, the significance of high-density lipoprotein (HDL) measurements is not as well documented as it is in humans. The HDL level can be measured in dogs as well and, through referring to the normal range, it is possible to find out what this means in relation to various endocrine diseases and hyperlipidemia diseases. The aim of this study is to measure the HDL levels in dogs with various conditions and to evaluate whether the total cholesterol (TC)-to-HDL ratio is effective as a prognostic indicator in various hyperlipidemia and endocrine diseases, which is significant since it is the first trial in dogs. Through a retrospective study design, sixteen client-owned dogs and cats visiting a local private practice were divided into three groups: five dogs without hyperlipidemia or metabolic disease (Group 1), eight dogs with Cushing's, hypothyroidism, and gallbladder sludge (Group 2), and three cats, including one with diabetes, one with a urinary disorder, and one healthy cat (Group 3). In two dogs, the TC/HDL values were between 2 and 3; in two dogs, the values were between 3 and 4; and in two dogs, the values were between 4 and 5. In three dogs, the TC/HDL values were between 5 and 6 and in three dogs the ratio values were between 6 and 7. The other value was higher than 8. Except for two dogs that showed lower values than 3, all dogs in Group 1 and Group 2 had concurrent endocrine disease. This means that TC/HDL values can be an excellent indicator of endocrine disease in dogs as well. In cats, although it is a very small batch of samples, a high TC/HDL value of 9 points was shown in the cat that had diabetes mellitus. However, for more statistically significant results, a larger sample group for further investigation is needed.

Dysfunctional HDL Diagnostic Metrics for Cardiovascular Disease Risk Stratification: Are we Ready to Implement in Clinics?

Epidemiological studies have revealed that patients with higher levels of high-density lipoprotein cholesterol (HDL-C) were more resistant to cardiovascular diseases (CVD), and yet targeting HDL for CVD prevention, risk assessment, and pharmacological management has not proven to be very effective. The mechanistic investigations have demonstrated that HDL exerts anti-atherogenic functions via mediating reverse cholesterol transport, antioxidant action, anti-inflammatory activity, and anti-thrombotic activity. Contrary to expectations, however, adverse cardiovascular events were reported in clinical trials of drugs that raised HDL levels. This has sparked a debate between HDL quantity and quality. Patients with atherosclerotic CVD are associated with dysfunctional HDL, and the degree of HDL dysfunction is correlated with the severity of the disease, independent of HDL-C levels. This growing body of evidence has underscored the need for integrating HDL functional assays in clinical practice for CVD risk management. Because HDL exerts diverse athero-protective functions, there is no single method for capturing HDL functionality. This review critically evaluates the various techniques currently being used for monitoring HDL functionality and discusses key structural changes in HDL indicative of dysfunctional HDL and the technical challenges that need to be addressed to enable the integration of HDL function-based metrics in clinical practice for CVD risk estimation and the development of newer therapies targeting HDL function.

A Multivariable Mendelian Randomization Study of Systolic and Diastolic Blood Pressure, Lipid Profile, and Heart Failure Subtypes

Heart failure (HF) is a significant health burden, with two major clinical subtypes: HF with reduced (HFrEF) and preserved ejection fraction (HFpEF). Blood pressure and lipid profile are established risk factors of HF. We performed univariable and multivariable Mendelian randomization (MR) analyses to assess potential causal effects of blood pressures and lipids on HF subtypes. Genetic instruments for blood pressures and lipids were derived from genome-wide association studies (GWASs) among the European participants of the UK Biobank. GWAS summaries of HFrEF and HFpEF were obtained from the meta-analysis of the European participants from the Million Veteran Program and the Vanderbilt University DNA Databank. Systolic blood pressure exhibited a supportive MR association primarily with HFpEF (odds ratio [OR], 1.14; 95% confidence interval [CI], 1.04-1.23), while diastolic blood pressure had an independent MR association with HFrEF (OR, 1.43; 95% CI, 1.13-1.77). MR associations also supported the observation that higher levels of low-density lipoprotein cholesterol increase the risk for both subtypes (HFrEF OR, 1.10 and 95% CI, 1.05-1.17; HFpEF OR, 1.05 and 95% CI, 1.02-1.09). These findings underscore differences in HF subtype-specific risk profiles and mechanisms, which may lead to different interventional strategies for different HF subtypes.

Association between human herpesvirus 8 and lipid profile in northwest China: A cross-sectional study

Human herpesvirus 8 (HHV-8) infection shows obvious regional and ethnic differences. Although studies have shown that these differences may be associated with lipid metabolism, to date, no large-scale studies have explored this. This study explored the seropositivity rate of HHV-8 among 2516 residents from 10 regions of northwest China and then the correlates of HHV-8 infection with lipid profile. The HHV-8 serological positivity rate was 15.6% among all residents. The HHV-8 seroprevalence ranged 11.2-27.6% among different ethnicities. Across different BMI levels, the positive rates of HHV-8 were 27.6%, 16.9%, and 13.6% for a BMI < 18.5, 18.5-24.9, and ≥25, respectively. HHV-8 seropositivity rate was lower for hypertensive people (12.6%) than for non-hypertensive people (16.7%). Univariate logistic regression analyses revealed that age, hypertension, systolic blood pressure, BMI, total cholesterol, and high-density lipoprotein cholesterol (HDL-C) significantly correlated with HHV-8 seropositivity (p < 0.05). Multivariate logistic regression analysis after adjusting for confounding factors showed that HDL-C (odds ratio [OR]: 0.132, 95% confidence interval [CI], 0.082-0.212; p < 0.001) and BMI (OR: 0.959, 95% CI 0.933-0.986; p = 0.003) were associated with HHV-8 seropositivity. Subgroup analyses concerning ethnicity, sex, or age demonstrated a consistent relationship with HDL-C. The results of HHV-8 seropositivity and BMI were inconsistent in the subgroups. However, Spearman's correlation analysis between HHV-8 serum antibody titer and HDL-C levels showed no linear relationship among HHV-8 seropositive individuals (ρ = -0.080, p = 0.058). HHV-8 serum antibody titers were also not significantly correlated with BMI (ρ = -0.015, p = 0.381). Low HDL-C levels may be an independent risk factor for HHV-8 infection, but there is no significant correlation between HDL-C levels and HHV-8 antibody titers.

HDL abnormalities in type 2 diabetes: Clinical implications

Atherosclerotic cardiovascular disease (ASCVD) represents the primary cause of mortality among patients with Type 2 Diabetes Mellitus (T2DM). In this population, High-Density Lipoprotein (HDL) particles exhibit abnormalities in number, composition, and function, culminating in diminished anti-atherosclerotic capabilities despite normal HDL cholesterol (HDL-C) concentrations. Hyperglycemic conditions contribute to these alterations in HDL kinetics, composition, and function, causing T2DM patients' HDL particles to exhibit decreased concentrations of diverse lipid species and proteins. Treatment of hyperglycemia has the potential to correct abnormal HDL particle attributes in T2DM; however, pharmacological interventions, including metformin and thiazolidinediones, yield inconsistent outcomes with respect to HDL-C concentrations and functionality. Despite numerous attempts with diverse drugs, pharmacologically augmenting HDL-C levels has not resulted in clinical benefits in mitigating ASCVD risk. In contrast, reducing Low Density Lipoprotein cholesterol (LDL-C) via statins and ezetimibe has demonstrated significant efficacy in curtailing CVD risk among T2DM individuals. Promising results have been observed in animal models and early-phase trials utilizing recombinant HDL and Lecitin Cholesterol Acyl Transferase (LCAT) -enhancing agents, but the evaluation of their efficacy and safety in large-scale clinical trials is ongoing. While aberrant HDL metabolism constitutes a prevalent aspect of dyslipidemia in T2DM, HDL cholesterol concentrations and composition no longer offer valuable insights for informing therapeutic decisions. Nevertheless, HDL metabolism remains a critical research area in T2DM, necessitating further investigation to elucidate the role of HDL particles in the development of diabetes-associated complications.

High-Density Lipoprotein Modifications: Causes and Functional Consequences in Type 2 Diabetes Mellitus

High-density lipoprotein (HDL) is a group of small, dense, and protein-rich lipoproteins that play a role in cholesterol metabolism and various cellular processes. Decreased levels of HDL and HDL dysfunction are commonly observed in individuals with type 2 diabetes mellitus (T2DM), which is also associated with an increased risk for cardiovascular disease (CVD). Due to hyperglycemia, oxidative stress, and inflammation that develop in T2DM, HDL undergoes several post-translational modifications such as glycation, oxidation, and carbamylation, as well as other alterations in its lipid and protein composition. It is increasingly recognized that the generation of HDL modifications in T2DM seems to be the main cause of HDL dysfunction and may in turn influence the development and progression of T2DM and its related cardiovascular complications. This review provides a general introduction to HDL structure and function and summarizes the main modifications of HDL that occur in T2DM. Furthermore, the potential impact of HDL modifications on the pathogenesis of T2DM and CVD, based on the altered interactions between modified HDL and various cell types that are involved in glucose homeostasis and atherosclerotic plaque generation, will be discussed. In addition, some perspectives for future research regarding the T2DM-related HDL modifications are addressed.

Correlation between serum uric acid to high-density lipoprotein cholesterol ratio and atrial fibrillation in patients with NAFLD

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is independently associated with atrial fibrillation (AF) risk. The uric acid (UA) to high-density lipoprotein cholesterol (HDL-C) ratio (UHR) has been shown to be closely associated with cardiovascular disease (CVD) and NAFLD. The aim of this study is to clarify whether elevated UHR is associated with the occurrence of AF in patients with NAFLD and to determine whether UHR predicted AF.

METHODS

Patients diagnosed with NAFLD in the Department of Cardiovascular Medicine of the Second Hospital of Shanxi Medical University from January 1, 2020, to December 31, 2021, were retrospectively enrolled in this study. The study subjects were categorized into AF group and non-AF group based on the presence or absence of combined AF. Logistic regression was performed to evaluate the correlation between UHR and AF. Sensitivity analysis and subgroup interaction analysis were performed to verify the robustness of the study results. Receiver operating characteristic (ROC) curve analysis was used to determine the optimal cutoff value for UHR to predict the development of AF in patients with NAFLD.

RESULTS

A total of 421 patients with NAFLD were included, including 171 in the AF group and 250 in the non-AF group. In the univariate regression analysis, NAFLD patients with higher UHR were more likely to experience AF, and the risk of AF persisted after confounding factors were adjusted for (OR: 1.010, 95%CI: 1.007-1.013, P<0.001). AF risk increased with increasing UHR quartile (P for trend < 0.001). Despite normal serum UA and HDL-C, UHR was still connected with AF in patients with NAFLD. All subgroup variables did not interact significantly with UHR in the subgroup analysis. The ROC curve analysis showed that the areas under the curve for UA, HDL-C, and UHR were 0.702, 0.606, and 0.720, respectively, suggesting that UHR has a higher predictive value for AF occurrence in NAFLD patients compared to HDL-C or UA alone.

CONCLUSION

Increased UHR level was independently correlated with a high risk of AF in NAFLD patients.

Bioactive TNIIIA2 Sequence in Tenascin-C Is Responsible for Macrophage Foam Cell Transformation; Potential of FNIII14 Peptide Derived from Fibronectin in Suppression of Atherosclerotic Plaque Formation

One of the extracellular matrix proteins, tenascin-C (TN-C), is known to be upregulated in age-related inflammatory diseases such as cancer and cardiovascular diseases. Expression of this molecule is frequently detected, especially in the macrophage-rich areas of atherosclerotic lesions; however, the role of TN-C in mechanisms underlying the progression of atherosclerosis remains obscure. Previously, we found a hidden bioactive sequence termed TNIIIA2 in the TN-C molecule and reported that the exposure of this sequence would be carried out through limited digestion of TN-C by inflammatory proteases. Thus, we hypothesized that some pro-atherosclerotic phenotypes might be elicited from macrophages when they were stimulated by TNIIIA2. In this study, TNIIIA2 showed the ability to accelerate intracellular lipid accumulation in macrophages. In this experimental condition, an elevation of phagocytic activity was observed, accompanied by a decrease in the expression of transporters responsible for lipid efflux. All these observations were mediated through the induction of excessive β1-integrin activation, which is a characteristic property of the TNIIIA2 sequence. Finally, we demonstrated that the injection of a drug that targets TNIIIA2's bioactivity could rescue mice from atherosclerotic plaque expansion. From these observations, it was shown that TN-C works as a pro-atherosclerotic molecule through an internal TNIIIA2 sequence. The possible advantages of clinical strategies targeting TNIIIA2 are also indicated.

HDL anti-inflammatory function is impaired and associated with high SAA1 and low APOA4 levels in aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating disease with high morbidity and mortality rates. Within 24 hours after aSAH, monocytes are recruited and enter the subarachnoid space, where they mature into macrophages, increasing the inflammatory response and contributing, along with other factors, to delayed neurological dysfunction and poor outcomes. High-density lipoproteins (HDL) are lipid-protein complexes that exert anti-inflammatory effects but under pathological conditions undergo structural alterations that have been associated with loss of functionality. Plasma HDL were isolated from patients with aSAH and analyzed for their anti-inflammatory activity and protein composition. HDL isolated from patients lost the ability to prevent VCAM-1 expression in endothelial cells (HUVEC) and subsequent adhesion of THP-1 monocytes to the endothelium. Proteomic analysis showed that HDL particles from patients had an altered composition compared to those of healthy subjects. We confirmed by western blot that low levels of apolipoprotein A4 (APOA4) and high of serum amyloid A1 (SAA1) in HDL were associated with the lack of anti-inflammatory function observed in aSAH. Our results indicate that the study of HDL in the pathophysiology of aSAH is needed, and functional HDL supplementation could be considered a novel therapeutic approach to the treatment of the inflammatory response after aSAH.

Membrane Cholesterol Interactions with Proteins in Hypercholesterolemia-Induced Endothelial Dysfunction

PURPOSE OF REVIEW

The goal of this review is to highlight work identifying mechanisms driving hypercholesterolemia-mediated endothelial dysfunction. We specifically focus on cholesterol-protein interactions and address specific questions related to the impact of hypercholesterolemia on cellular cholesterol and vascular endothelial function. We describe key approaches used to determine the effects of cholesterol-protein interactions in mediating endothelial dysfunction under dyslipidemic conditions.

RECENT FINDINGS

The benefits of removing the cholesterol surplus on endothelial function in models of hypercholesterolemia is clear. However, specific mechanisms driving cholesterol-induced endothelial dysfunction need to be determined. In this review, we detail the latest findings describing cholesterol-mediated endothelial dysfunction, highlighting our studies indicating that cholesterol suppresses endothelial Kir2.1 channels as a major underlying mechanism. The findings detailed in this review support the targeting of cholesterol-induced suppression of proteins in restoring endothelial function in dyslipidemic conditions. The identification of similar mechanisms regarding other cholesterol-endothelial protein interactions is warranted.

Association of HDL Subfraction Profile with the Progression of Insulin Resistance

Type 2 diabetes mellitus (T2DM) is a major global public health problem, as it is associated with increased morbidity, mortality, and healthcare costs. Insulin resistance (IR) is a condition characterized by disturbances in carbohydrate and lipid metabolism that precedes T2DM. The aim of the present study was to investigate the association between HDL and its subfraction profile and the progression of IR, as assessed by the Homeostatic Model Assessment for IR (HOMA-IR) index, and to define cut-off values to identify an increased risk of IR. Individuals with a HOMA-IR greater than 3.63 were considered to have IR. The HDL subfractions were separated using the Lipoprint system, which identifies ten subfractions (HDL-1-10) in three subclasses as large (HDL-L), intermediate (HDL-I) and small (HDL-S). Analyses were performed on samples from 240 individuals without IR and 137 with IR from the Hungarian general and Roma populations. The HDL-1 to -6 subfractions and the HDL-L and -I classes showed a significant negative association with the progression and existence of IR. Among them, HDL-2 (B = -40.37, p = 2.08 × 10-11) and HDL-L (B = -14.85, p = 9.52 × 10-10) showed the strongest correlation. The optimal threshold was found to be 0.264 mmol/L for HDL-L and 0.102 mmol/L and above for HDL-2. Individuals with HDL-L levels below the reference value had a 5.1-fold higher risk of IR (p = 2.2 × 10-7), while those with HDL-2 levels had a 4.2-fold higher risk (p = 3.0 × 10-6). This study demonstrates that the HDL subfraction profile (especially the decrease in HDL-2 and -L) may be a useful marker for the early detection and intervention of atherogenic dyslipidemia in subjects with impaired glucose and insulin metabolism.

Blood C-peptide concentration as a proxy marker of cardiovascular disease: An observational cross-sectional study

Background and Aims

Cardiovascular diseases (CVDs) are among the leading causes of disability and early death in sub-Saharan Africa. Most of the current blood tests for CVD diagnosis involve performing about three test profiles; often at additional cost to patients. C-peptide, a cleavage product of proinsulin, is a promising marker that has the potential to serve as a proxy marker for diagnosing CVDs in resource-poor settings.

Methodology

The study was an observational cross-sectional one and involved 127 consenting persons diagnosed with CVD and 127 individuals without CVD. The socio-demographic and clinical characteristics of participants were obtained. Blood levels of C-peptide, fasting plasma glucose (FPG), total creatinine kinase (CK), creatine kinase myocardial bound (CKMB), lactate dehydrogenase (LDH), propeptide of brain natriuretic peptide (PBNP), Troponin T, lipids, and biomarkers of kidney and liver function were analyzed using ELISA and an automated analyzer. Insulin resistance was computed using the modified homeostatic model assessment (HOMA-IR).

Results

The CVD Group had significantly higher levels of C-peptide, CK, CKMB, troponin T, PBNP, FPG, HOMA-IR, and several selected kidney, liver, and lipid parameters compared to the non-CVD Group (p < 0.05 for all). Troponin T recorded a positive correlation (r = 0.34, p < 0.001) with C-peptide among the CVD Group. The sensitivity and specificity of C-peptide in identifying CVD were 96.1% and 91.3% respectively (area under the curve = 0.938, p < 0.001).

Conclusion

C-peptide levels were higher in the CVD Group and appeared to be a valuable (high sensitivity and specificity) biomarker in detecting CVD.

Alteration and clinical potential in gut microbiota in patients with cerebral small vessel disease

Background

Cerebral small vessel disease (CSVD) is a cluster of microvascular disorders with unclear pathological mechanisms. The microbiota-gut-brain axis is an essential regulatory mechanism between gut microbes and their host. Therefore, the compositional and functional gut microbiota alterations lead to cerebrovascular disease pathogenesis. The current study aims to determine the alteration and clinical value of the gut microbiota in CSVD patients.

Methods

Sixty-four CSVD patients and 18 matched healthy controls (HCs) were included in our study. All the participants underwent neuropsychological tests, and the multi-modal magnetic resonance imaging depicted the changes in brain structure and function. Plasma samples were collected, and the fecal samples were analyzed with 16S rRNA gene sequencing.

Results

Based on the alpha diversity analysis, the CSVD group had significantly decreased Shannon and enhanced Simpson compared to the HC group. At the genus level, there was a significant increase in the relative abundances of Parasutterella, Anaeroglobus, Megasphaera, Akkermansia, Collinsella, and Veillonella in the CSVD group. Moreover, these genera with significant differences in CSVD patients revealed significant correlations with cognitive assessments, plasma levels of the blood-brain barrier-/inflammation-related indexes, and structural/functional magnetic resonance imaging changes. Functional prediction demonstrated that lipoic acid metabolism was significantly higher in CSVD patients than HCs. Additionally, a composite biomarker depending on six gut microbiota at the genus level displayed an area under the curve of 0.834 to distinguish CSVD patients from HCs using the least absolute shrinkage and selection operator (LASSO) algorithm.

Conclusion

The evident changes in gut microbiota composition in CSVD patients were correlated with clinical features and pathological changes of CSVD. Combining these gut microbiota using the LASSO algorithm helped identify CSVD accurately.

Association between axial length and HDL in children: a hospital-based cross-sectional study

BACKGROUND

To analyze the relationship between axial length and levels of high-density lipoprotein (HDL) cholesterol in children.

METHODS

A retrospective, hospital-based cross-sectional research with 69 right eyes from 69 children who underwent health examination by Zhejiang Provincial People's Hospital was carried out. The participants were split into three groups: Group A (axial length < = 23 mm), Group B (axial length 23-24 mm), and Group C (axial length > 24 mm). Demographic epidemiological information, blood biochemical parameters and ophthalmic characteristics including refractive status and ocular geometric parameters were obtained and analyzed.

RESULTS

69 right eyes from 69 patients (25 males and 44 females) with a median age of 10.00 years old (IQR: 8.00-11.00 years) were included in the study. Within Group A, there were a total of 17 individuals; Group B consisted of 22 individuals; Group C included 30 individuals. The mean axial length of three groups was 22.148(0.360), 23.503(0.342) and 24.770(0.556) mm, respectively (p < 0.0001). The mean HDL levels were significantly different in three groups are 1.824(0.307), 1.485(0.253) and 1.507 (0.265) mmol/L, respectively. By applying a Pearson Coefficient, we evaluated the association between axial length and HDL and discovered that there was a statistically significant (p = 0.00025) and adverse (R = -0.43) association between axial length and HDL.

CONCLUSIONS

We concluded from our study that there was a significantly inverse relationship between axial length and the levels of HDL in children.

Utility of neutrophil-to-high-density lipoprotein-cholesterol ratio in patients with coronary artery disease: a narrative review

The neutrophil-to-high-density lipoprotein-cholesterol ratio (NHR) is thought to reflect inflammatory status and dyslipidaemia, both of which play significant roles in coronary artery disease (CAD). The objective of this narrative review is to summarise the results of studies that have explored the utility of NHR for the diagnosis and management of CAD. The PubMed, Google Scholar, Scopus, Embase and Web of Science databases were searched for articles related to NHR from their inception to October 2022. Seven relevant articles were obtained for review. There were unclear relationships of NHR with age, sex, smoking status, hypertension and diabetes. However, NHR had a sensitivity and specificity as high as 94.8% and 59%, respectively, for the identification of significant coronary stenosis. NHR was also a superior predictor of prognosis to conventional parameters. NHR had a sensitivity and specificity as high as 77.6% and 74.2%, respectively, for the prediction of adverse events, including mortality, associated with acute coronary syndrome. Thus, NHR could be used in clinical cardiovascular medicine for risk stratification and the prediction of the short-term and long-term outcomes of CAD. However, more studies are required before a quantitative assessment of the efficacy of NHR for use in patient management can be completed.

Syndecan-1: From a Promising Novel Cardiac Biomarker to a Surrogate Early Predictor of Kidney and Liver Injury in Patients with Acute Heart Failure

(1) Background: Acute heart failure (HF) represents a complex clinical syndrome burdened by increased mortality and a high rate of systemic complications. Although natriuretic peptides (e.g., NT-proBNP) currently represent the diagnostic and prognostic gold standard in acute HF, those molecules do not accurately reflect all the pathophysiological mechanisms involved in the progression of this pathology when determined independently. Therefore, the current paradigm tends to focus on a multi-marker approach for the risk stratification of patients with acute HF. Syndecan-1 is a less studied biomarker in cardiovascular diseases; its assessment in patients with acute HF being potentially able to reflect the myocardial pathological changes, such as fibrosis, inflammation, endothelial dysfunction or global wall stress. (2) Methods: We conducted a single center prospective study that enrolled 173 patients (120 patients admitted for acute HF, compared to 53 controls with stable chronic HF). A complete standardized clinical, echocardiography and laboratory evaluation was performed at admission, including serum samples for the determination of syndecan-1 by the enzyme-linked immunosorbent assay (ELISA) method. (3) Results: The serum concentration of syndecan-1 was significantly higher in patients with acute HF, compared to controls [121.4 (69.3–257.9) vs. 72.1 (41.4–135.8) ng/mL, p = 0.015]. Syndecan-1 was a significant predictor for the diagnosis of acute HF, expressed by an area under the curve (AUC) of 0.898, similar to NT-proBNP (AUC: 0.976) or cardiac troponin (AUC: 0.839). Moreover, syndecan-1 was independently associated with impaired kidney and liver function at admission, being also a predictor for early, subclinical organ dysfunction in patients with normal biological parameters at admission. When included in the multi-marker model, syndecan-1 levels influenced mortality more significantly than NT-proBNP or troponin. A multivariable regression including syndecan-1, NT-proBNP and troponin provided additional prognostic value compared to each independent biomarker. (4) Conclusions: Syndecan-1 can be considered a promising novel biomarker in acute HF, exhibiting adequate diagnostic and prognostic value. Additionally, syndecan-1 can be used as a surrogate biomarker for non-cardiac organ dysfunction, as its highs levels can accurately reflect early acute kidney and liver injury.

Sepsis-Induced Coagulopathy Phenotype Induced by Oxidized High-Density Lipoprotein Associated with Increased Mortality in Septic-Shock Patients

Sepsis syndrome is a highly lethal uncontrolled response to an infection, which is characterized by sepsis-induced coagulopathy (SIC). High-density lipoprotein (HDL) exhibits antithrombotic activity, regulating coagulation in vascular endothelial cells. Sepsis induces the release of several proinflammatory molecules, including reactive oxygen species, which lead to an increase in oxidative stress in blood vessels. Thus, circulating lipoproteins, such as HDL, are oxidized to oxHDL, which promotes hemostatic dysfunction, acquiring prothrombotic properties linked to the severity of organ failure in septic-shock patients (SSP). However, a rigorous and comprehensive investigation demonstrating that oxHDL is associated with a coagulopathy-associated deleterious outcome of SSP, has not been reported. Thus, we investigated the participation of plasma oxHDL in coagulopathy-associated sepsis pathogenesis and elucidated the underlying molecular mechanism. A prospective study was conducted on 42 patients admitted to intensive care units, (26 SSP and 16 non-SSP) and 39 healthy volunteers. We found that an increased plasma oxHDL level in SSP was associated with a prothrombotic phenotype, increased mortality and elevated risk of death, which predicts mortality in SSP. The underlying mechanism indicates that oxHDL triggers an endothelial protein expression reprogramming of coagulation factors and procoagulant adhesion proteins, to produce a prothrombotic environment, mainly mediated by the endothelial LOX-1 receptor. Our study demonstrates that an increased plasma oxHDL level is associated with coagulopathy in SSP through a mechanism involving the endothelial LOX-1 receptor and endothelial protein expression regulation. Therefore, the plasma oxHDL level plays a role in the molecular mechanism associated with increased mortality in SSP.

Low HDL-Cholesterol Concentrations in Lung Transplant Candidates are Strongly Associated With One-Year Mortality After Lung Transplantation

High-density lipoproteins (HDLs), whose main role is the reverse transport of cholesterol, also have pleiotropic anti-inflammatory, antioxidant, anti-apoptotic and anti-infectious properties. During sepsis, HDL cholesterol (HDL-C) concentration is low, HDL particle functionality is altered, and these modifications are correlated with poor outcomes. Based on the protective effects of HDL, we hypothesized that HDL-C levels could be associated with lung transplantation (LT) outcome. We thus looked for an association between basal HDL-C concentration and one-year mortality after LT. In this single-center prospective study including consecutive LTs from 2015 to 2020, 215 patients were included, essentially pulmonary fibrosis (47%) and chronic obstructive pulmonary disease (COPD) (38%) patients. Mortality rate at one-year was 23%. Basal HDL-C concentration stratified nonsurvivors to survivors at one-year (HDL-C = 1.26 [1.12-1.62] mmol/L vs. HDL-C = 1.55 [1.22-1.97] mmol/L, p = 0.006). Multivariate analysis confirmed that HDL-C concentration during the pretransplant assessment period was the only variable inversely associated with mortality. Moreover, mortality at one-year in patients with HDL-C concentrations ≤1.45 mmol/L was significantly higher (log-rank test, p = 0.00085). In conclusion, low basal HDL-C concentrations in candidates for LT are strongly associated with mortality after LT. To better understand this association, further studies in this field are essential and, in particular, a better characterization of HDL particles seems necessary.

Sphingolipids and Atherosclerosis: The Dual Role of Ceramide and Sphingosine-1-Phosphate

Sphingolipids are bioactive molecules that play either pro- and anti-atherogenic roles in the formation and maturation of atherosclerotic plaques. Among SLs, ceramide and sphingosine-1-phosphate showed antithetic properties in regulating various molecular mechanisms and have emerged as novel potential targets for regulating the development of atherosclerosis. In particular, maintaining the balance of the so-called ceramide/S1P rheostat is important to prevent the occurrence of endothelial dysfunction, which is the trigger for the entire atherosclerotic process and is strongly associated with increased oxidative stress. In addition, these two sphingolipids, together with many other sphingolipid mediators, are directly involved in the progression of atherogenesis and the formation of atherosclerotic plaques by promoting the oxidation of low-density lipoproteins (LDL) and influencing the vascular smooth muscle cell phenotype. The modulation of ceramide and S1P levels may therefore allow the development of new antioxidant therapies that can prevent or at least impair the onset of atherogenesis, which would ultimately improve the quality of life of patients with coronary artery disease and significantly reduce their mortality.

Oxidized High-Density Lipoprotein Induces Endothelial Fibrosis Promoting Hyperpermeability, Hypotension, and Increased Mortality

During systemic inflammation, reactive oxygen species (ROS) are generated in the bloodstream, producing large amounts of oxidized HDL (oxHDL). OxHDL loses the vascular protective features of native HDL, acquiring detrimental actions. Systemic inflammation promotes endothelial fibrosis, characterized by adhesion protein downregulation and fibrotic-specific gene upregulation, disrupting endothelial monolayer integrity. Severe systemic inflammatory conditions, as found in critically ill patients in the intensive care unit (ICU), exhibit endothelial hyperpermeability, hypotension, and organ hypoperfusion, promoting organ dysfunction and increased mortality. Because endothelial fibrosis disturbs the endothelium, it is proposed that it is the cellular and molecular origin of endothelial hyperpermeability and the subsequent deleterious consequences. However, whether oxHDL is involved in this process is unknown. The aim of this study was to investigate the fibrotic effect of oxHDL on the endothelium, to elucidate the underlying molecular and cellular mechanism, and to determine its effects on vascular permeability, blood pressure, and mortality. The results showed that oxHDL induces endothelial fibrosis through the LOX-1/NOX-2/ROS/NF-κB pathway, TGF-β secretion, and ALK-5/Smad activation. OxHDL-treated rats showed endothelial hyperpermeability, hypotension, and an enhanced risk of death and mortality, which was prevented using an ALK-5 inhibitor and antioxidant diet consumption. Additionally, the ICU patients showed fibrotic endothelial cells, and the resuscitation fluid volume administered correlated with the plasma oxHDL levels associated with an elevated risk of death and mortality. We conclude that oxHDL generates endothelial fibrosis, impacting blood pressure regulation and survival.

Effects of Antirheumatic Treatment on Cell Cholesterol Efflux and Loading Capacity of Serum Lipoproteins in Spondylarthropathies

Spondyloarthropathies (SpA) are associated with increased cardiovascular risk. Among possible mechanisms is the dysfunction of serum lipoproteins in regulating cell cholesterol homeostasis. Cholesterol efflux capacity (CEC)-the atheroprotective ability of HDL (high density lipoproteins) to accept cholesterol from macrophages-might predict cardiovascular disease independently of HDL-cholesterol levels. We aimed at evaluating modifications of CEC and of the atherogenic cholesterol loading capacity (CLC) of serum lipoproteins in psoriatic arthritis (PsA) and ankylosing spondylitis (AS) following anti-rheumatic treatment. A total of 62 SpA patients (37 PsA and 25 AS) were evaluated before and after treatment with tumor necrosis factor inhibitor and/or methotrexate. CEC and CLC were measured by radioisotopic and fluorometric techniques, respectively. Endothelial function was assessed by finger plethysmography (Endopat). In the whole SpA group, total and HDL-cholesterol increased after treatment, while lipoprotein(a) decreased and CLC was unchanged. Treatment was associated with increased Scavenger Receptor class B type I (SR-BI)-mediated CEC in the AS group. SR-BI- and ABCG1-mediated CEC were negatively associated with inflammatory parameters and positively related to coffee consumption. SR-BI CEC and CLC were positively and negatively associated with endothelial function, respectively. Our pilot study suggests that anti-rheumatic treatment is associated with favorable modulation of lipoprotein quality and function in SpA, particularly in AS, in spite of the induced increase in total cholesterol levels. If confirmed in a larger population, this might represent an atheroprotective benefit beyond what is reflected by conventional serum lipid profile.

Atherogenic index of plasma is an independent predictor of mitral annular calcification

BACKGROUND

In the latest reports, atherogenic indices have been related to acute coronary syndromes, stable coronary artery disease, heart failure and future cardiac events. Conventional atherosclerosis risk factors have been associated with mitral annular calcification (MAC), but data on the relationship between atherogenic indices and MAC are lacking. We aimed to investigate a possible relationship between MAC and atherogenic indices.

METHODS

In total 741 patients (n = 427 with MAC and n = 314 without MAC) who were examined in our cardiology clinic from February 2016 to October 2021 were recruited in the study. Mitral annular calcification was diagnosed by transthoracic 2-dimensional echocardiography. The atherogenic coefficient (AC), Castelli risk index 1 (CRI-1), Castelli risk index 2 (CRI-2) and atherogenic index of plasma (AIP) were calculated by utilizing standard lipid test values.

RESULTS

There was no statistically significant difference in sex, age, diabetes and hypertension status between the patient and the control groups. Serum triglyceride level, AIP, Hs-CRP, smoking and BMI were independently significantly associated with MAC in multiple regression analysis (p < 0.001).

CONCLUSION

Higher AIP was related to the existence of MAC and also predict the presence of MAC independently. Studies evaluating the modification of these indices are needed.

Shear Stress and Metabolic Disorders-Two Sides of the Same Plaque

Significance: Shear stress and metabolic disorder are the two sides of the same atherosclerotic coin. Atherosclerotic lesions are prone to develop at branches and curvatures of arteries, which are exposed to oscillatory and low shear stress exerted by blood flow. Meanwhile, metabolic disorders are pivotal contributors to the formation and advancement of atherosclerotic plaques. Recent Advances: Accumulated evidence has provided insight into the impact and mechanisms of biomechanical forces and metabolic disorder on atherogenesis, in association with mechanotransduction, epigenetic regulation, and so on. Moreover, recent studies have shed light on the cross talk between the two drivers of atherosclerosis. Critical Issues: There are extensive cross talk and interactions between shear stress and metabolic disorder during the pathogenesis of atherosclerosis. The communications may amplify the proatherogenic effects through increasing oxidative stress and inflammation. Nonetheless, the precise mechanisms underlying such interactions remain to be fully elucidated as the cross talk network is considerably complex. Future Directions: A better understanding of the cross talk network may confer benefits for a more comprehensive clinical management of atherosclerosis. Critical mediators of the cross talk may serve as promising therapeutic targets for atherosclerotic vascular diseases, as they can inhibit effects from both sides of the plaque. Hence, further in-depth investigations with advanced omics approaches are required to develop novel and effective therapeutic strategies against atherosclerosis. Antioxid. Redox Signal. 37, 820-841.

Neutrophil to high-density lipoprotein cholesterol ratio predicts adverse cardiovascular outcomes in subjects with pre-diabetes: a large cohort study from China

Background

This study aimed to examine whether the neutrophil to high-density lipoprotein cholesterol ratio (NHR) can predict cardiovascular outcomes in normoglycemic individuals with elevated fasting glucose levels.

Methods

A total of 130,801 participants with normal blood glucose levels were enrolled in the Kailuan study. Participants were categorized according to NHR quartiles and further divided into normal glucose regulation (NGR) and pre-diabetes (pre-DM) subgroups. The follow-up endpoint was major adverse cardiovascular events (CVE), including stroke and myocardial infarction.

Results

Over a median of 12.53 (8.95–13.08) years of follow-up, subjects with NHR levels in the highest quartile experienced more CVE than those with NHR levels in the lowest quartile. Multivariate Cox analyses showed that continuous changes in NHR (hazard ratio, 1.21; 95% confidence interval [CI], 1.15–1.28) and the highest quartile of NHR (hazard ratio, 1.30; 95% CI, 1.21–1.39) were independent predictors of CVE (all P < 0.001). Furthermore, when participants were categorized by both NHR quartile and glucose metabolism status, the NHR level in the highest quartile plus pre-DM group was associated with a 1.60-fold (95% CI, 1.38–1.86; P < 0.001] higher risk of CVE than that in the lowest quartile plus normoglycemic group. Significantly, the addition of NHR only, presence of pre-DM only, or combination of NHR and pre-DM to the prediction algorithm, including traditional risk factors, improved the C-statistic by 0.19, 0.05, and 0.23 (all P < 0.001).

Conclusions

Elevated NHR or fasting blood glucose level were independently associated with a higher risk of CVE among normoglycemic individuals. Moreover, pre-DM participants with high NHR levels tended to have worse prognosis, suggesting that NHR could provide greater risk stratification value than traditional risk factors for subjects with pre-DM.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-022-01695-x.

High-density lipoproteins may play a crucial role in COVID-19

Background

Lipids play a central role in the virus life cycle and are a crucial target to develop antiviral therapeutics. Importantly, among the other lipoproteins, the ‘good cholesterol’ high-density lipoprotein (HDL) has been widely studied for its role in not only cardiovascular but several infectious diseases as well. Studies have suggested a role of serum lipids and lipoproteins including HDL, total cholesterol (TC), triglycerides (TG), and low-density lipoproteins (LDL) in several viral infections including COVID-19. This disease is currently a major public health problem and there is a need to explore the role of these host lipids/lipoproteins in virus pathogenesis.

Methodology

A total of 75 retrospective COVID-19 positive serum samples and 10 COVID-19 negative controls were studied for their lipid profiles including TC, HDL, LDL, and very-low-density lipoproteins (VLDL), and TG.

Results

Systematic literature search on dyslipidemia status in India shows that low HDL is the most common dyslipidemia. In this cohort, 65% (49) of COVID-19 patients had severely low HDL levels whereas 35% (26) had moderately low HDL and none had normal HDL levels. On the other hand, ~ 96% of samples had normal TC (72) and LDL (72) levels. VLDL and TG levels were also variable. In the controls, 100% of samples had moderately low HDL but none severely low HDL levels.

Conclusion

HDL likely plays a crucial role in COVID-19 infection and outcomes. The causal relationships between HDL levels and COVID-19 need to be studied extensively for an understanding of disease pathogenesis and management.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12985-022-01865-4.

Relationship between liver dysfunction, lipoprotein concentration and mortality during sepsis

Background

High-density lipoproteins (HDLs) are synthesized by the liver and display endothelioprotective properties, including anti-inflammatory, antiapoptotic, antithrombotic and antioxidant effects. In both septic and chronic liver failure patients, a low HDL cholesterol (HDL-C) concentration is associated with overmortality. Whereas sepsis-associated liver dysfunction is poorly defined, the aim of this study was to characterize the relationship between liver dysfunction, lipoprotein concentrations and mortality in septic patients in the intensive care unit (ICU).

Methods

A prospective observational study was conducted in a university hospital ICU. All consecutive patients admitted for septic shock or sepsis were included. Total cholesterol, HDL-C, low-density lipoprotein-cholesterol (LDL-C), and triglyceride levels were assessed at admission. Sepsis-associated liver dysfunction was defined as a serum bilirubin≥ 2N or aspartate aminotransferase/alanine aminotransferase concentrations ≥ 2N. Short-term and one-year prognostic outcomes were prospectively assessed.

Results

A total of 219 septic patients were included, and 15% of them presented with sepsis-associated liver dysfunction at admission. Low concentrations of lipoproteins were associated with mortality at Day 28 in the overall population. Sepsis-associated liver dysfunction at admission was associated with overmortality. In this subgroup, patients had a lower HDL-C concentration than patients without hepatic dysfunction (HDL-C = 0.31 [0.25, 0.55] mmol/L vs. 0.48 [0.29, 0.73] mmol/L, p = 0.0079) but there was no relationship with the outcome. Interestingly, no correlation was observed between lipoprotein concentrations and liver dysfunction markers.

Conclusion

Sepsis-associated liver dysfunction at ICU admission is strongly associated with overmortality and is associated with a lower HDL-C concentration. However, in this subgroup of patients, HDL-C concentration had no relationship with mortality. Further exploratory studies are needed to better understand the interaction between lipoproteins and liver dysfunction during sepsis.

Monocyte to high-density lipoprotein ratio predict long-term clinical outcomes in patients with coronary heart disease: A meta-analysis of 9 studies

BACKGROUND

A novel inflammation-related biomarker, the monocyte to high-density lipoprotein cholesterol ratio (MHR), had a great relation to the development and prognosis of coronary atherosclerotic heart disease. Current study was to investigate whether the MHR was a potential tool in predicting the mortality and major adverse cardiac events (MACEs) in patients suffering coronary heart disease (CHD) by meta-analysis.

METHODS

The Cochrane Library, PubMed, MEDLINE, Scopus, EMBASE, and Web of science were searched for relevant cohort studies published prior to February 10, 2022. The association between MHR and mortality/MACEs was analyzed in patients with CHD. Hazard ratios (HR) with 95% confidence interval (CI) were calculated to estimate the strength of association.

RESULTS

In the meta-analysis, a total of 9 studies of 11,345 patients with CHD were included. Compared with the low level of MHR group, the high MHR value was associated with higher long-term MACEs (HR = 1.72 95% CI 1.36-2.18, P < .001), long-term mortality (HR = 1.71, 95% CI 1.10-2.66, P = .017), and in-hospital mortality/MACEs (HR = 2.82, 95% CI = 1.07-7.41, P = .036).

CONCLUSIONS

This study suggested that increased MHR value might be associated with higher long-term mortality and long-term MACEs in CHD patients. MHR might serve as a potential prognostic indicator for risk stratification in patients with CHD.

Bidirectional Control between Cholesterol Shuttle and Purine Signal at the Central Nervous System

Recent studies have highlighted the mechanisms controlling the formation of cerebral cholesterol, which is synthesized in situ primarily by astrocytes, where it is loaded onto apolipoproteins and delivered to neurons and oligodendrocytes through interactions with specific lipoprotein receptors. The “cholesterol shuttle” is influenced by numerous proteins or carbohydrates, which mainly modulate the lipoprotein receptor activity, function and signaling. These molecules, provided with enzymatic/proteolytic activity leading to the formation of peptide fragments of different sizes and specific sequences, could be also responsible for machinery malfunctions, which are associated with neurological, neurodegenerative and neurodevelopmental disorders. In this context, we have pointed out that purines, ancestral molecules acting as signal molecules and neuromodulators at the central nervous system, can influence the homeostatic machinery of the cerebral cholesterol turnover and vice versa. Evidence gathered so far indicates that purine receptors, mainly the subtypes P2Y2, P2X7 and A2A, are involved in the pathogenesis of neurodegenerative diseases, such as Alzheimer’s and Niemann–Pick C diseases, by controlling the brain cholesterol homeostasis; in addition, alterations in cholesterol turnover can hinder the purine receptor function. Although the precise mechanisms of these interactions are currently poorly understood, the results here collected on cholesterol–purine reciprocal control could hopefully promote further research.

Conductance Artery Wall Layers and Their Respective Roles in the Clearance Functions

Evolutionary organization of the arterial wall into layers occurred concomitantly with the emergence of a highly muscularized, pressurized arterial system that facilitates outward hydraulic conductance and mass transport of soluble substances across the arterial wall. Although colliding circulating cells disperse potential energy within the arterial wall, the different layers counteract this effect: (1) the endothelium ensures a partial barrier function; (2) the media comprises smooth muscle cells capable of endocytosis/phagocytosis; (3) the outer adventitia and perivascular adipocytic tissue are the final receptacles of convected substances. While the endothelium forms a physical and a biochemical barrier, the medial layer is avascular, relying on the specific permeability properties of the endothelium for metabolic support. Different components of the media interact with convected molecules: medial smooth muscle cells take up numerous molecules via scavenger receptors and are capable of phagocytosis of macro/micro particles. The outer layers-the highly microvascularized innervated adventitia and perivascular adipose tissue-are also involved in the clearance functions of the media: the adventitia is the seat of immune response development, inward angiogenesis, macromolecular lymphatic drainage, and neuronal stimulation. Consequently, the clearance functions of the arterial wall are physiologically essential, but also may favor the development of arterial wall pathologies. This review describes how the walls of large conductance arteries have acquired physiological clearance functions, how this is determined by the attributes of the endothelial barrier, governed by endocytic and phagocytic capacities of smooth muscle cells, impacting adventitial functions, and the role of these clearance functions in arterial wall diseases.

Plasma apoM Levels and Progression to Kidney Dysfunction in Patients With Type 1 Diabetes

Apolipoprotein M (apoM), primarily carried by HDL, has been associated with several conditions, including cardiovascular disease and diabetic nephropathy. This study proposes to examine whether plasma apoM levels are associated with the development of diabetic kidney disease, assessed as progression to macroalbuminuria (MA) and chronic kidney disease (CKD). Plasma apoM was measured using an enzyme immunoassay in 386 subjects from the Diabetes Control and Complications Trial (DCCT)/Epidemiology of Diabetes Interventions and Complications (EDIC) cohort at DCCT entry and closeout and the concentrations used to determine the association with risk of progression to kidney dysfunction from the time of measurement through 18 years of EDIC follow-up. apoM levels, at DCCT baseline, were higher in patients who developed CKD than in those who retained normal renal function. At DCCT closeout, participants who progressed to MA, CKD, or both MA and CKD also had significantly higher apoM levels than those who remained normal, and increased levels of apoM were associated with increased risk of progression to both MA (risk ratio [RR] 1.30 [95% CI 1.01, 1.66]) and CKD (RR 1.69 [95% CI 1.18, 2.44]). Our results strongly suggest that alterations in apoM and therefore in the composition and function of HDL in type 1 diabetes are present early in the disease process and are associated with the development of nephropathy.

A Potential Interplay between HDLs and Adiponectin in Promoting Endothelial Dysfunction in Obesity

Obesity is an epidemic public health problem that has progressively worsened in recent decades and is associated with low-grade chronic inflammation (LGCI) in metabolic tissues and an increased risk of several diseases. In particular, LGCI alters metabolism and increases cardiovascular risk by impairing endothelial function and altering the functions of adiponectin and high-density lipoproteins (HDLs). Adiponectin is an adipokine involved in regulating energy metabolism and body composition. Serum adiponectin levels are reduced in obese individuals and negatively correlate with chronic sub-clinical inflammatory markers. HDLs are a heterogeneous and complex class of lipoproteins that can be dysfunctional in obesity. Adiponectin and HDLs are strictly interdependent, and the maintenance of their interplay is essential for vascular function. Since such a complex network of interactions is still overlooked in clinical settings, this review aims to highlight the mechanisms involved in the impairment of the HDLs/adiponectin axis in obese patients to predict the risk of cardiovascular diseases and activate preventive countermeasures. Here, we provide a narrative review of the role of LGCI in altering HDLs, adiponectin and endothelial functions in obesity to encourage new studies about their synergic effects on cardiovascular health and disease.

Aortic dysfunction by chronic cadmium exposure is linked to multiple metabolic risk factors that converge in anion superoxide production

CONTEXT

The chronic exposure to Cadmium (Cd) constitute an risk to develop hypertension and cardiovascular diseases associated with the increase of oxidative stress.

OBJECTIVE

In this study, we investigate the role of metabolic changes produced by exposure to Cd on the endothelial dysfunction via oxidative stress.

METHODS

Male Wistar rats were exposed to Cd (32.5-ppm) for 2-months. The zoometry and blood pressure were evaluated, also glucose and lipids profiles in serum and vascular reactivity evaluated in isolated aorta rings.

RESULTS

Rats exposed to Cd showed an increase of blood pressure and biochemical parameters similar to metabolic syndrome. Additionally, rats exposed to Cd showed a reduced relaxation in aortic rings, which was reversed after the addition of SOD and apocynin an inhibitor of NADPH.

CONCLUSION

The Cd-exposition induced hypertension and endothelial injury by that modifying the vascular relaxation and develop oxidative stress via NADPH oxidase, superoxide and loss nitric oxide bioavailability.

The Interplay of Endothelial P2Y Receptors in Cardiovascular Health: From Vascular Physiology to Pathology

The endothelium plays a key role in blood vessel health. At the interface of the blood, it releases several mediators that regulate local processes that protect against the development of cardiovascular disease. In this interplay, there is increasing evidence for a role of extracellular nucleotides and endothelial purinergic P2Y receptors (P2Y-R) in vascular protection. Recent advances have revealed that endothelial P2Y₁-R and P2Y₂-R mediate nitric oxide-dependent vasorelaxation as well as endothelial cell proliferation and migration, which are processes involved in the regeneration of damaged endothelium. However, endothelial P2Y₂-R, and possibly P2Y₁-R, have also been reported to promote vascular inflammation and atheroma development in mouse models, with endothelial P2Y₂-R also being described as promoting vascular remodeling and neointimal hyperplasia. Interestingly, at the interface with lipid metabolism, P2Y₁₂-R has been found to trigger HDL transcytosis through endothelial cells, a process known to be protective against lipid deposition in the vascular wall. Better characterization of the role of purinergic P2Y-R and downstream signaling pathways in determination of the endothelial cell phenotype in healthy and pathological environments has clinical potential for the prevention and treatment of cardiovascular diseases.

Study on the correlation between high density lipoprotein and lower extremities deep venous thrombosis in patients undergoing hip arthroplasty

OBJECTIVE

To explore the relationship between high density lipoprotein (HDL) and lower extremities deep venous thrombosis (DVT) in patients undergoing hip arthroplasty.

METHODS

A total of 348 patients undergoing hip arthroplasty in our hospital were enrolled, and divided into observation (n = 154, 44.25%) and control (n = 194, 55.75%) groups according to the occurrence of lower extremities DVT. The presence of DVT was assessed 1 day before surgery and routinely every 2 days after surgery. The factors of DVT were analyzed by single factor analysis, multivariate logistic regression analysis, and Pearson correlation.

RESULTS

The age and body mass index in the observation group were significantly higher (p = .045, p = .041, respectively), while HDL-C was significantly lower (p = .032) than the control group. Increase age, high BMI, low apolipoprotein-A1 level and low HDL-C level were risk factors for lower extremities DVT. The mean HDL-C in the observation and control groups was 0.91 ± 0.27 and 1.19 ± 0.37, respectively, the adjusted odds ratio was 1.050; 95% CI 1.010-1.092, p = .014.

CONCLUSION

Elderly patients with high BMI and low HDL-C level undergoing hip arthroplasty are at risk of lower extremities DVT, and should be paid attention to clinically.

First Recombinant High-Density Lipoprotein Particles Administration in a Severe ICU COVID-19 Patient, a Multi-Omics Exploratory Investigation

High-density lipoproteins (HDLs) have multiple endothelioprotective properties. During SARS-CoV-2 infection, HDL-cholesterol (HDL-C) concentration is markedly reduced, and studies have described severe impairment of the functionality of HDL particles. Here, we report a multi-omic investigation of the first administration of recombinant HDL (rHDL) particles in a severe COVID-19 patient in an intensive care unit. Plasma ApoA1 increased and HDL-C decreased after each recombinant HDL injection, suggesting that these particles were functional in terms of reverse cholesterol transport. The proportion of large HDL particles also increased after injection of recombinant HDL. Shotgun proteomics performed on HDLs isolated by ultracentrifugation indicated that ApoA1 was more abundant after injections whereas most of the pro-inflammatory proteins identified were less abundant. Assessment of Serum amyloid A-1, inflammatory markers, and cytokines showed a significant decrease for most of them during recombinant HDL infusion. Our results suggest that recombinant HDL infusion is feasible and a potential therapeutic strategy to be explored in COVID-19 patients.

ApoA-I Nanoparticles as Curcumin Carriers for Cerebral Endothelial Cells: Improved Cytoprotective Effects against Methylglyoxal

Methylglyoxal (MGO) is a highly reactive metabolite of glucose present at elevated levels in diabetic patients. Its cytotoxicity is associated with endothelial dysfunction, which plays a role in cardiovascular and cerebrovascular complications. Although curcumin has many therapeutic benefits, these are limited due to its low bioavailability. We aimed to improve the bioavailability of curcumin and evaluate a potential synergistic effect of curcumin and reconstituted high-density lipoprotein (rHDL) nanoparticles (Cur-rHDLs) on MGO-induced cytotoxicity and oxidative stress in murine cerebrovascular endothelial cells (bEnd.3). Cur-rHDL nanoparticles (14.02 ± 0.95 nm) prepared by ultracentrifugation and containing curcumin were quantified by LC–MS/MS. The synergistic effect of cur-rHDL nanoparticles was tested on bEnd.3 cytotoxicity, reactive oxygen species (ROS) production, chromatin condensation, endoplasmic reticulum (ER) stress, and endothelial barrier integrity by impedancemetry. The uptake of curcumin, alone or associated with HDLs, was also assessed by mass spectrometry. Pretreatment with Cur-rHDLs followed by incubation with MGO showed a protective effect on MGO-induced cytotoxicity and chromatin condensation, as well as a strong protective effect on ROS production, endothelial cell barrier integrity, and ER stress. These results suggest that Cur-rHDLs could be used as a potential therapeutic agent to limit MGO-induced dysfunction in cerebrovascular endothelial cells by enhancing the bioavailability and protective effects of curcumin.

HDL Composition, Heart Failure, and Its Comorbidities

Although research on high-density lipoprotein (HDL) has historically focused on atherosclerotic coronary disease, there exists untapped potential of HDL biology for the treatment of heart failure. Anti-oxidant, anti-inflammatory, and endothelial protective properties of HDL could impact heart failure pathogenesis. HDL-associated proteins such as apolipoprotein A-I and M may have significant therapeutic effects on the myocardium, in part by modulating signal transduction pathways and sphingosine-1-phosphate biology. Furthermore, because heart failure is a complex syndrome characterized by multiple comorbidities, there are complex interactions between heart failure, its comorbidities, and lipoprotein homeostatic mechanisms. In this review, we will discuss the effects of heart failure and associated comorbidities on HDL, explore potential cardioprotective properties of HDL, and review novel HDL therapeutic targets in heart failure.

Sphingosine 1-phosphate and its regulatory role in vascular endothelial cells

Sphingosine 1-phosphate (S1P) is a bioactive metabolite of sphingomyelin. S1P activates a series of signaling cascades by acting on its receptors S1PR1-3 on endothelial cells (ECs), which plays an important role in endothelial barrier maintenance, anti-inflammation, antioxidant and angiogenesis, and thus is considered as a potential therapeutic biomarker for ischemic stroke, sepsis, idiopathic pulmonary fibrosis, cancers, type 2 diabetes and cardiovascular diseases. We presently review the levels of S1P in those vascular and vascular-related diseases. Plasma S1P levels were reduced in various inflammation-related diseases such as atherosclerosis and sepsis, but were increased in other diseases including type 2 diabetes, neurodegeneration, cerebrovascular damages such as acute ischemic stroke, Alzheimer's disease, vascular dementia, angina, heart failure, idiopathic pulmonary fibrosis, community-acquired pneumonia, and hepatocellular carcinoma. Then, we highlighted the molecular mechanism by which S1P regulated EC biology including vascular development and angiogenesis, inflammation, permeability, and production of reactive oxygen species (ROS), nitric oxide (NO) and hydrogen sulfide (H₂S), which might provide new ways for exploring the pathogenesis and implementing individualized therapy strategies for those diseases.

Monocyte-to-HDL ratio and non-HDL cholesterol were predictors of septic shock in newborns

BACKGROUND

The association between lipoprotein levels and late-onset neonatal sepsis has shown controversial results. The aims are to assess lipid profile, cytokines, and Monocyte-to-HDL (M/H) ratio as diagnostic and prognostic markers for late-onset neonatal sepsis.

METHODS

This prospective study included 49 septic neonates and 17 controls. Cholesterol (CT), Triglyceride (TG), Very-Low-Density (VLDLc), Low-Density (LDLc), and High-Density Lipoproteins (HDLc) were measured at admission (D0) and on days 3, 7 and 10 to evaluate septic shock outcomes. Cytokines and monocytes were evaluated by flow cytometry.

RESULTS

Septic newborns showed higher IL-6 and IL-8 at D0 and CT levels on D7 and on D10, which also presented higher TG, VLDLc and non-HDL cholesterol concentrations than controls. The septic shock group (n = 22) revealed a higher number of male subjects, CRP, IL-6, IL-8 and IL-10 levels, while lower TG, HDLc, monocyte numbers and M/H ratio at admission compared to the non-shock group (n = 27). M/H ratio and non-HDL cholesterol on D0 were risk factors for septic shock (OR = 0.70, 0.49‒0.99; OR = 0.96, 0.92‒0.99, respectively). Decreasing levels from D0 to D3 of CT (OR = 0.96, 0.93‒0.99), VLDLc (OR = 0.91, 0.85‒0.98), and non-HDL cholesterol (OR = 0.92, 0.87‒0.98) were also predictors of septic shock.

CONCLUSIONS

Lower M/H ratios and non-HDL cholesterol at admission and decreasing levels of cholesterol, VLDLc and non-HDL cholesterol during a hospital stay are associated with the development of septic shock in newborns with late-onset neonatal sepsis.

Dysfunctional Vascular Endothelium as a Driver of Atherosclerosis: Emerging Insights Into Pathogenesis and Treatment

Atherosclerosis, the chronic accumulation of cholesterol-rich plaque within arteries, is associated with a broad spectrum of cardiovascular diseases including myocardial infarction, aortic aneurysm, peripheral vascular disease, and stroke. Atherosclerotic cardiovascular disease remains a leading cause of mortality in high-income countries and recent years have witnessed a notable increase in prevalence within low- and middle-income regions of the world. Considering this prominent and evolving global burden, there is a need to identify the cellular mechanisms that underlie the pathogenesis of atherosclerosis to discover novel therapeutic targets for preventing or mitigating its clinical sequelae. Despite decades of research, we still do not fully understand the complex cell-cell interactions that drive atherosclerosis, but new investigative approaches are rapidly shedding light on these essential mechanisms. The vascular endothelium resides at the interface of systemic circulation and the underlying vessel wall and plays an essential role in governing pathophysiological processes during atherogenesis. In this review, we present emerging evidence that implicates the activated endothelium as a driver of atherosclerosis by directing site-specificity of plaque formation and by promoting plaque development through intracellular processes, which regulate endothelial cell proliferation and turnover, metabolism, permeability, and plasticity. Moreover, we highlight novel mechanisms of intercellular communication by which endothelial cells modulate the activity of key vascular cell populations involved in atherogenesis, and discuss how endothelial cells contribute to resolution biology - a process that is dysregulated in advanced plaques. Finally, we describe important future directions for preclinical atherosclerosis research, including epigenetic and targeted therapies, to limit the progression of atherosclerosis in at-risk or affected patients.

Plasma atherogenic indices are independent predictors of slow coronary flow

Background

Although the pathophysiology of coronary slow flow (CSF) has not been fully elucidated, emerging data increasingly support potential role for subclinical diffuse atherosclerosis in the etiology of CSF. We aimed to investigate relationship between atherogenic indices and CSF.

Methods

130 patients with CSF diagnosed according to Thrombolysis in Myocardial Infarction (TIMI)-frame count (TFC) method and 130 controls who had normal coronary flow (NCF) were included in this retrospective study. Atherogenic indices (atherogenic index of plasma [AIP], Castelli risk indices I and II [CRI-I and II]) were calculated using conventional lipid parameters.

Results

The logistic regression analyses demonstrated that AIP (OR, 5.463; 95% confidence interval [CI], 1.357–21.991; p = 0.017) and CRI-II (OR, 1.624; 95% CI, 1.138–2.319; p = 0.008) were independent predictors of CSF. Receiver operating characteristic analysis showed that the optimal cutoff value to predict the occurrence of CSF was 0.66 for AIP (sensitivity, 59%; specificity, 73%; area under curve [AUC], 0.695; p < 0.001) and 3.27 for CRI-II (sensitivity, 60%; specificity, 79%; AUC, 0.726; p < 0.001).

Conclusions

AIP and CRI-II levels were independent predictors of CSF. Prospective studies in larger cohorts of patients may elucidate the role of atherogenic dyslipidemia in the pathophysiology of CSF.