Effect of niacin monotherapy on high density lipoprotein composition and function

HDL-associated vitamin D binding protein levels are inversely associated with necrotic plaque burden in psoriasis

Background and aims

Vitamin D binding protein (DBP) serves a dual function as a vitamin D carrier and actin scavenger. Free DBP is present in high concentrations in serum, while a smaller pool is bound to lipoproteins like HDL and VLDL. The role of DBP's interaction with lipoproteins remains unclear. Given that HDL has been proposed to have both atheroprotective and anti-inflammatory properties, we sought to compare whether HDL-associated DBP and/or total serum DBP could serve as useful biomarkers for assessing disease severity in psoriasis and cardiovascular disease.

Methods

Psoriasis (PSO) patients (N = 83), which were part of a prospective, observational cohort and non-psoriasis (non-PSO) subjects (n = 35) underwent blood collection for HDL purification by liquid chromatography and CCTA scans to assess coronary plaque burden. Serum and HDL-bound DBP levels were measured by ELISA.

Results

The psoriasis cohort was middle-aged (mean ± IQR: 50 (38-59), predominantly male (n = 55, 66 %) and had moderate-to-severe skin disease [psoriasis area severity index score, PASI score, med (IQR): 9.6 (6-18.3)]. Consistent with our previous reports, PSO patients had significantly higher Framingham Risk Score (FRS), high sensitivity C-reactive protein (hs-CRP), Body Mass Index (BMI), insulin resistance (HOMA-IR) and total coronary plaque burden, driven by the rupture-prone non-calcified necrotic core. However, while the concentration of serum DBP (S-DBP) between PSO and non-PSO was unchanged (PSO: 177.80 (125.77-250.99) vs non-PSO: 177.74 (104.32-254.04), the concentration of DBP associated with HDL (HDL-DBP) was decreased in psoriatics (PSO μg/ml: 1.38 (0.64-2.75) vs non-PSO: 1.72 (1.18-3.90). Although both S-DBP and HDL-DBP levels showed inverse correlations with a measure of skin disease severity (PASI) (S-DBP, Rho = -0.022 vs HDL-DBP, Rho = -113), only HDL-DBP exhibited an inverse relationship with necrotic plaque burden [Rho -0.226, p = 0.085 vs S-DBP (0.041, p = 0.76)]. This relationship was strengthened after adjusting for traditional cardiovascular risk factors such as age and sex (β = -0.237, p = 0.045), FRS (β = -0.295, p = 0.033) and including biological treatment and HDL-cholesterol (β = -0.213, p = 0.048).

Conclusions

In conclusion, we found HDL-DBP levels may better capture the severity of psoriatic disease and association with cardiovascular risk factors than S-DBP.

Association of dietary niacin intake with all-cause mortality in chronic kidney disease: A retrospective cohort study of NHANES

BACKGROUND

Dietary niacin intake has a positive influence on several chronic diseases, while the impact of dietary niacin intake on prognosis in chronic kidney disease (CKD) remains unknown. The study would explore the association between dietary niacin intake and all-cause mortality in CKD patients.

METHODS

Data about 4,659 CKD patients in this retrospective cohort study were obtained from the National Health and Nutrition Examinations Survey (NHANES). Dietary niacin intake data were acquired based on the 24-hour dietary recall interviews. Weighted univariate Cox regression models were utilized to select potential covariates. The association of dietary niacin intake with all-cause mortality was explored using weighted univariate and multivariate Cox regression models. The results were presented as hazard ratios (HRs) with 95% confidence intervals (CIs).

RESULTS

In total, 4,659 CKD patients were included in the study. The mean age of patients was 58.03 (0.42) years old, and 2,502 (58.45%) were female. During a mean follow-up of 73.92 (1.14) months, 1,325 (28.44%) CKD patients died. Compared to CKD patients with lower niacin intake ≤19mg, those with niacin intake >33 mg were associated with lower all-cause mortality risk (HR = 0.79, 95%CI: 0.64-0.98). The association also found in subgroups of age ≥65 years old (HR = 0.68, 95%CI: 0.53-0.88), males (HR = 0.68, 95%CI: 0.51-0.92), BMI <25 kg/m2 (HR = 0.63, 95%CI: 0.39-0.99), smoking (HR = 0.68, 95%CI: 0.49-0.94), dyslipidemia (HR = 0.71, 95%CI: 0.56-0.91), and non-hyperphosphatemia (HR = 0.73, 95%CI: 0.58-0.91).

CONCLUSION

Adequate dietary niacin intake was related to lower odds of all-cause mortality in CKD patients. Niacin supplements may have potential benefits for prognosis in CKD patients.

The Pleiotropic Effects of Lipid-Modifying Interventions: Exploring Traditional and Emerging Hypolipidemic Therapies

Atherosclerotic cardiovascular disease poses a significant global health issue, with dyslipidemia standing out as a major risk factor. In recent decades, lipid-lowering therapies have evolved significantly, with statins emerging as the cornerstone treatment. These interventions play a crucial role in both primary and secondary prevention by effectively reducing cardiovascular risk through lipid profile enhancements. Beyond their primary lipid-lowering effects, extensive research indicates that these therapies exhibit pleiotropic actions, offering additional health benefits. These include anti-inflammatory properties, improvements in vascular health and glucose metabolism, and potential implications in cancer management. While statins and ezetimibe have been extensively studied, newer lipid-lowering agents also demonstrate similar pleiotropic effects, even in the absence of direct cardiovascular benefits. This narrative review explores the diverse pleiotropic properties of lipid-modifying therapies, emphasizing their non-lipid effects that contribute to reducing cardiovascular burden and exploring emerging benefits for non-cardiovascular conditions. Mechanistic insights into these actions are discussed alongside their potential therapeutic implications.

Reduced HDL-cholesterol in long COVID-19: A key metabolic risk factor tied to disease severity

This controlled study investigated metabolic changes in non-vaccinated individuals with Long-COVID-19, along with their connection to the severity of the disease. The study involved 88 patients who experienced varying levels of initial disease severity (mild, moderate, and severe), and a control group of 29 healthy individuals. Metabolic risk markers from fasting blood samples were analyzed, and data regarding disease severity indicators were collected. Findings indicated significant metabolic shifts in severe Long-COVID-19 cases, mainly a marked drop in HDL-C levels and a doubled increase in ferritin levels and insulin resistance compared to the mild cases and controls. HDL-C and ferritin were identified as the leading factors predicted by disease severity. In conclusion, the decline in HDL-C levels and rise in ferritin levels seen in Long-COVID-19 individuals, largely influenced by the severity of the initial infection, could potentially play a role in the persistence and progression of Long-COVID-19. Hence, these markers could be considered as possible therapeutic targets, and help shape preventive strategies to reduce the long-term impacts of the disease.

Differences in vascular endothelial function and serum proteome between obese people with phlegm-dampness constitution and balanced constitution

OBJECTIVE

To evaluate the extent of vascular endothelial dysfunction and preliminary identify serum protein biomarkers associated with obese individuals at risk for cardiovascular disease (CVD).

METHODS

Fifteen obese volunteers with the phlegm-dampness constitution or balanced constitution were recruited for this study respectively. The clinical baseline data was collected, and the vascular endothelial function was evaluated using the EndoPATTM. Blood samples were collected for the serum proteome analysis. The differences in the serum protein expression levels between the two groups were detected and the protein interaction network analysis, correlation analysis, receiver operating characteristic (ROC) curve analysis, and random forest model investigation were conducted.

RESULTS

There were no statistical differences found in the baseline data. For vascular endothelial function, the reactive hyperemia index (RHI) of the phlegm-dampness constitution obese group was significantly lower than that of the balanced constitution obese group (1.46 ± 0.30 vs 2.82 ± 0.78, P < 0.0001), indicating vascular endothelial dysfunction. There are 66 differentially expressed serum proteins between the two groups. apolipoprotein A2 (ApoA2), angiotensin-converting enzyme 2 (ACE-2), interleukin-33 (IL-33), and forkhead box P3 (FoxP3) showed significant differences and area under curve values of their ROC curves were greater than 0.7 and correlated significantly with RHI.

CONCLUSION

Vascular endothelial dysfunction was present in the phlegm-dampness constitution obese group. Thus, alterations in the expression levels of key serum proteins, including ApoA2, ACE-2, IL-33, and FoxP3 could serve as potential biomarkers in the obese population at risk of CVD.

Flaxseed Reduces Cancer Risk by Altering Bioenergetic Pathways in Liver: Connecting SAM Biosynthesis to Cellular Energy

This article illustrates how dietary flaxseed can be used to reduce cancer risk, specifically by attenuating obesity, type 2 diabetes, and non-alcoholic fatty liver disease (NAFLD). We utilize a targeted metabolomics dataset in combination with a reanalysis of past work to investigate the "metabo-bioenergetic" adaptations that occur in White Leghorn laying hens while consuming dietary flaxseed. Recently, we revealed how the anti-vitamin B6 effects of flaxseed augment one-carbon metabolism in a manner that accelerates S-adenosylmethionine (SAM) biosynthesis. Researchers recently showed that accelerated SAM biosynthesis activates the cell's master energy sensor, AMP-activated protein kinase (AMPK). Our paper provides evidence that flaxseed upregulates mitochondrial fatty acid oxidation and glycolysis in liver, concomitant with the attenuation of lipogenesis and polyamine biosynthesis. Defatted flaxseed likely functions as a metformin homologue by upregulating hepatic glucose uptake and pyruvate flux through the pyruvate dehydrogenase complex (PDC) in laying hens. In contrast, whole flaxseed appears to attenuate liver steatosis and body mass by modifying mitochondrial fatty acid oxidation and lipogenesis. Several acylcarnitine moieties indicate Randle cycle adaptations that protect mitochondria from metabolic overload when hens consume flaxseed. We also discuss a paradoxical finding whereby flaxseed induces the highest glycated hemoglobin percentage (HbA1c%) ever recorded in birds, and we suspect that hyperglycemia is not the cause. In conclusion, flaxseed modifies bioenergetic pathways to attenuate the risk of obesity, type 2 diabetes, and NAFLD, possibly downstream of SAM biosynthesis. These findings, if reproducible in humans, can be used to lower cancer risk within the general population.

Proteomic analysis of postprandial high-density lipoproteins in healthy subjects

The relationship between the functionality and composition of high-density lipoproteins (HDL) is yet not fully studied, and little is known about the influence of the diet in HDL proteome. Therefore, the aim of this research was to elucidate the HDL proteome associated to postprandial hyperlipidemia. Male volunteers were recruited for an interventional study with high fatty acid-based meals. Blood samples were collected before the intake (baseline), and 2-3 (postprandial peak) and 5-6 (postprandial post peak) hours later. HDL were purified and the protein composition was quantified by LC-MS/MS. Statistical analysis was performed by lineal models (amica) and by ANOVA and multi-t-test of the different conditions (MetaboAnalyst). Additionally, a clustering of the expression profiles of each protein was done with coseq R package (RStudio). Initially, 320 proteins were identified but only 119 remained after the filtering. APOM, APOE, APOB, and APOA2, proteins previously identified in the HDL proteome, were the only proteins with a statistically significant altered expression in postprandial hyperlipidemia when compared to baseline (p values <0.05 and logFC >1). In conclusion, we have been able to describe several behaviors of the whole HDL proteome during the postprandial hyperlipidemic metabolism.

Dietary niacin intake and risk of dyslipidemia: A pooled analysis of three prospective cohort studies

BACKGROUND & AIMS

Although the pharmacological effect of niacin in lowering blood cholesterol and triglyceride levels has been demonstrated in several clinical studies, information regarding the effect of dietary niacin intake is uncertain, and the longitudinal association between dietary niacin intake and the risk of dyslipidemia has not been adequately studied.

METHODS

We analyzed data from three community-based cohort studies in Korea, including 211,567 participants aged ≥40 years. Dietary niacin intake was estimated using a validated semi-quantitative food frequency questionnaire, and the occurrence of dyslipidemia was confirmed through surveys during the follow-up period. We applied Cox proportional hazard regression to calculate the cohort-specific hazard ratio (HR) and 95% confidence interval (CI) for dyslipidemia and pooled the results using the fixed-effects method.

RESULTS

Higher dietary niacin intake was associated with a reduced risk of dyslipidemia (pooled, multivariable-adjusted HR: 0.71, 95% CI: 0.62-0.82). Compared with the group whose dietary niacin intake was above the recommended dietary allowance in Korea, the risk of dyslipidemia increased by 32% (pooled, multivariable-adjusted HR: 1.32, 95% CI: 1.19-1.46) in the group below the estimated average requirement in Korea. Spline regression showed a dose-response linear relationship between dietary niacin intake and the risk of dyslipidemia (all p-values for nonlinearity >0.05).

CONCLUSION

Consumption of foods with high niacin levels may help prevent or delay the onset of dyslipidemia.

Mitochondrial Lipid Homeostasis at the Crossroads of Liver and Heart Diseases

The prevalence of NAFLD (non-alcoholic fatty liver disease) is a rapidly increasing problem, affecting a huge population around the globe. However, CVDs (cardiovascular diseases) are the most common cause of mortality in NAFLD patients. Atherogenic dyslipidemia, characterized by plasma hypertriglyceridemia, increased small dense LDL (low-density lipoprotein) particles, and decreased HDL-C (high-density lipoprotein cholesterol) levels, is often observed in NAFLD patients. In this review, we summarize recent genetic evidence, proving the diverse nature of metabolic pathways involved in NAFLD pathogenesis. Analysis of available genetic data suggests that the altered operation of fatty-acid β-oxidation in liver mitochondria is the key process, connecting NAFLD-mediated dyslipidemia and elevated CVD risk. In addition, we discuss several NAFLD-associated genes with documented anti-atherosclerotic or cardioprotective effects, and current pharmaceutical strategies focused on both NAFLD treatment and reduction of CVD risk.

[Plasma high density lipoproteins phospholipds as an indirect indicator of their cholesterol efflux capacity - new suspected atherosclerosis risk factor]

High density lipoproteins (HDL) are a unique natural structure, protecting the body from the development of atherosclerotic vascular lesions and cardiovascular diseases due to this ability to remove cholesterol from cells. Plasma HDL level estimated by their cholesterol content, is a common lipid parameter, and its decrease is considered as an established atherosclerosis risk factor. However, a number of studies have shown the absence of positive clinical effects after drug-induced increase in HDL cholesterol. There is increasing evidence that not only HDL concentration, but also HDL properties, considered in this review are important. Many studies showed the decrease of HDL cholesterol efflux capacity in patients with coronary heart diseases and its association with disease severity. Some authors consider a decrease of this HDL capacity as a new additional risk factor of atherosclerosis. The review summarizes existing information on various protein and lipid components of HDL with a primary emphasis on the HDL. Special attention is paid to correlation between the HDL cholesterol efflux capacity and HDL phospholipids and the ratio "phospholipids/free cholesterol". The accumulated information indicates importance of evaluation in the HDL fraction not only in terms of their cholesterol, but also phospholipids. In addition to the traditionally used lipid criteria, this would provide more comprehensive information about the activity of the reverse cholesterol transport process in the body and could contribute to the targeted correction of the detected disorders.

High Density Lipoprotein Cholesterol Efflux Capacity and Atherosclerosis in Cardiovascular Disease: Pathophysiological Aspects and Pharmacological Perspectives

Over the years, the relationship between high-density lipoprotein (HDL) and atherosclerosis, initially highlighted by the Framingham study, has been revealed to be extremely complex, due to the multiple HDL functions involved in atheroprotection. Among them, HDL cholesterol efflux capacity (CEC), the ability of HDL to promote cell cholesterol efflux from cells, has emerged as a better predictor of cardiovascular (CV) risk compared to merely plasma HDL-cholesterol (HDL-C) levels. HDL CEC is impaired in many genetic and pathological conditions associated to high CV risk such as dyslipidemia, chronic kidney disease, diabetes, inflammatory and autoimmune diseases, endocrine disorders, etc. The present review describes the current knowledge on HDL CEC modifications in these conditions, focusing on the most recent human studies and on genetic and pathophysiologic aspects. In addition, the most relevant strategies possibly modulating HDL CEC, including lifestyle modifications, as well as nutraceutical and pharmacological interventions, will be discussed. The objective of this review is to help understanding whether, from the current evidence, HDL CEC may be considered as a valid biomarker of CV risk and a potential pharmacological target for novel therapeutic approaches.