Niacin Increases Atherogenic Proteins in High-Density Lipoprotein of Statin-Treated Subjects

Pitavastatin treatment remodels the HDL subclass lipidome and proteome in hypertriglyceridemia

HDL particles vary in lipidome and proteome, which dictate their individual physicochemical properties, metabolism, and biological activities. HDL dysmetabolism in nondiabetic hypertriglyceridemia (HTG) involves subnormal HDL-cholesterol and apoAI levels. Metabolic anomalies may impact the qualitative features of both the HDL lipidome and proteome. Whether particle content of bioactive lipids and proteins may differentiate HDL subclasses (HDL2b, 2a, 3a, 3b, and 3c) in HTG is unknown. Moreover, little is known of the effect of statin treatment on the proteolipidome of hypertriglyceridemic HDL and its subclasses. Nondiabetic, obese, HTG males (n = 12) received pitavastatin calcium (4 mg/day) for 180 days in a single-phase, unblinded study. ApoB-containing lipoproteins were normalized poststatin. Individual proteolipidomes of density-defined HDL subclasses were characterized prestatin and poststatin. At baseline, dense HDL3c was distinguished by marked protein diversity and peak abundance of surface lysophospholipids, amphipathic diacylglycerol and dihydroceramide, and core cholesteryl ester and triacylglycerol, (normalized to mol phosphatidylcholine), whereas light HDL2b showed peak abundance of free cholesterol, sphingomyelin, glycosphingolipids (monohexosylceramide, dihexosylceramide, trihexosylceramide, and anionic GM3), thereby arguing for differential lipid transport and metabolism between subclasses. Poststatin, bioactive lysophospholipid (lysophosphatidylcholine, lysoalkylphosphatidylcholine, lysophosphatidylethanolamine, and lysophosphatidylinositol) cargo was preferentially depleted in HDL3c. By contrast, baseline lipidomic profiles of ceramide, dihydroceramide and related glycosphingolipids, and GM3/phosphatidylcholine were maintained across particle subclasses. All subclasses were depleted in triacylglycerol and diacylglycerol/phosphatidylcholine. The abundance of apolipoproteins CI, CII, CIV, and M diminished in the HDL proteome. Statin treatment principally impacts metabolic remodeling of the abnormal lipidome of HDL particle subclasses in nondiabetic HTG, with lesser effects on the proteome.

Identifying the natural products in the treatment of atherosclerosis by increasing HDL-C level based on bioinformatics analysis, molecular docking, and in vitro experiment

BACKGROUND

Previous studies have demonstrated that high-density lipoprotein cholesterol (HDL-C) plays an anti-atherosclerosis role through reverse cholesterol transport. Several studies have validated the efficacy and safety of natural products in treating atherosclerosis (AS). However, the study of raising HDL-C levels through natural products to treat AS still needs to be explored.

METHODS

The gene sets associated with AS were collected and identified by differential gene analysis and database query. By constructing a protein-protein interaction (PPI) network, the core submodules in the network are screened out. At the same time, by calculating node importance (Nim) in the PPI network of AS disease and combining it with Kyoto Encyclopedia of genes and genomes (KEGG) pathways enrichment analysis, the key target proteins of AS were obtained. Molecular docking is used to screen out small natural drug molecules with potential therapeutic effects. By constructing an in vitro foam cell model, the effects of small molecules on lipid metabolism and key target expression of foam cells were investigated.

RESULTS

By differential gene analysis, 451 differential genes were obtained, and a total of 313 disease genes were obtained from 6 kind of databases, then 758 AS-related genes were obtained. The enrichment analysis of the KEGG pathway showed that the enhancement of HDL-C level against AS was related to Lipid and atherosclerosis, Cholesterol metabolism, Fluid shear stress and atherosclerosis, PPAR signaling pathway, and other pathways. Then we intersected 31 genes in the core module of the PPI network, the top 30 genes in Nims, and 32 genes in the cholesterol metabolism pathway, and finally found 3 genes. After the above analysis and literature collection, we focused on the following three related gene targets: APOA1, LIPC, and CETP. Molecular docking showed that Genistein has a good binding affinity for APOA1, CETP, and LIPC. In vitro, experiments showed that Genistein can up-regulated APOA1, LIPC, and CETP levels.

CONCLUSIONS

Based on our research, Genistein may have the effects of regulating HDL-C and anti-atherosclerosis. Its mechanism of action may be related to the regulation of LIPC, CETP, and APOA1 to improve lipid metabolism.

NAD+ Precursors in Human Health and Disease: Current Status and Future Prospects

Significance: Nicotinamide adenine dinucleotide (NAD+) acts as a cofactor in many important biological processes. The administration of NAD+ precursors increases the intracellular NAD+ pool and has beneficial effects on physiological changes and diseases associated with aging in various organisms, including rodents and humans. Recent Advances: Evidence from preclinical studies demonstrating the beneficial effects of NAD+ precursors has rapidly increased in the last decade. The results of these studies have prompted the development of clinical trials using NAD+ precursors, particularly nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN). In addition, in vivo studies of NAD+ metabolism have rapidly progressed. Critical Issues: Several studies have demonstrated that the oral administration of NAD+ precursors, such as NR and NMN, is safe and significantly increases NAD+ levels in humans. However, the efficacy of these NAD+ precursors is lower than expected from the results of preclinical studies. In addition, the identification of the contribution of the host-gut microbiota interactions to NR and NMN metabolism has added to the complexity of NAD+ metabolism. Future Directions: Further studies are required to determine the efficacy of NAD+ precursors in humans. Further in vivo studies of NAD+ metabolism are required to optimize the effects of NAD+ supplementation. There is also a need for methods of delivering NAD+ precursors to target organs or tissues to increase the outcomes of clinical trials. Antioxid. Redox Signal. 39, 1133-1149.

Association between niacin intake and depression: A nationwide cross-sectional study

BACKGROUND

The association between dietary intake and depression is receiving increasing attention. However, the relationship between depressive symptoms and niacin intake is still unclear. The purpose of this study was to explore the association between niacin intake and depressive symptoms.

METHODS

We used univariate analysis and multivariate logistic regression equations to explore the association between covariates or niacin intake and depression. Generalized additive models and smoothing fitted curves were used to examine the presence of nonlinear relationships. Upon finding a nonlinear relationship, a recursive algorithm was used to calculate the inflection point . Population differences were also explored through stratified analysis.

RESULTS

In the model adjusted for all covariates，the ORs (95 % CI) for the association between niacin intake and depression were 0.94 (0.87, 1.01), which was no statistical significance. However, the result of the linear trend test with quartiles of niacin intake indicated the association between niacin intake and depression may be U-shaped. The generalized additive model confirmed this U-shaped relationship, finding an inflection point (26.6 mg/d). An opposite relationship was observed before and after the inflection point, with ORs (95 % CI) of 0.77 (0.68, 0.87) before the inflection point and 1.13 (1.01, 1.28) after the inflection point. The association in men, Mexican American, White, adults aged<40, and BMI <30 was consistent with the overall tendency.

CONCLUSION

We found a U-shaped association between niacin intake and depression in the general American population, and the same association was observed in men, Mexican American, White, adults aged < 40, and BMI < 30.

Severe hypertriglyceridemia: Existing and emerging therapies

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

Role of Vitamins in Cardiovascular Health: Know Your Facts - Part 1

Cardiovascular (CV) disease (CVD) is a major cause of morbidity and mortality world-wide, thus it is important to adopt preventive interventions. Observational data demonstrating CV benefits of vitamin supplements, advanced by self-proclaimed experts have resulted in ~50% of Americans reporting the use of multivitamins for health promotion; this practice has led to a multi-billion-dollar business of the multivitamin-industry. However, the data on the extensive use of multivitamins show no consistent benefit for CVD prevention or all-cause mortality, while the use of certain vitamins might prove harmful. Thus, the focus of this two-part review is on the attributes or concerns about specific vitamins on CVD. In Part 1, the CV effects of specific vitamins are discussed, indicating the need for further supportive evidence of potential benefits. Vitamin A preserves CV homeostasis as it participates in many biologic functions, including atherosclerosis. However, supplementation could potentially be harmful. Betacarotene, a pro-vitamin A, conveys pro-oxidant actions that may mitigate any other benefits. Folic acid alone and certain B-vitamins (e.g., B1/B2/B6/B12) may reduce CVD, heart failure, and/or stroke, while niacin might increase mortality. Vitamin C has antioxidant and cardioprotective effects. Vitamin D may confer CV protection, but all the data are not in agreement. Combined vitamin E and C have antiatherogenic effects but clinical evidence is inconsistent. Vitamin K seems neutral. Thus, there are individual vitamin actions with favorable CV impact (certain B-vitamins and vitamins C and D), but other vitamins (β-carotene, niacin) may potentially have deleterious effects, which also holds true for high doses of fat-soluble vitamins (A/D/E/K).

New Progress in Early Diagnosis of Atherosclerosis

Coronary atherosclerosis is a potentially chronic circulatory condition that endangers human health. The biological cause underpinning cardiovascular disease is coronary atherosclerosis, and acute cardiovascular events can develop due to thrombosis, platelet aggregation, and unstable atherosclerotic plaque rupture. Coronary atherosclerosis is progressive, and three specific changes appear, with fat spots and stripes, atherosclerosis and thin-walled fiber atherosclerosis, and then complex changes in arteries. The progression and severity of cardiovascular disease are correlated with various levels of calcium accumulation in the coronary artery. The therapy and diagnosis of coronary atherosclerosis benefit from the initial assessment of the size and degree of calcification. This article will discuss the new progress in the early diagnosis of coronary atherosclerosis in terms of three aspects: imaging, gene and protein markers, and trace elements. This study intends to present the latest methods for diagnosing patients with early atherosclerosis through a literature review.

Decoding microRNA drivers in Atherosclerosis

An estimated 97% of the human genome consists of non-protein-coding sequences. As our understanding of genome regulation improves, this has led to the characterization of a diverse array of non-coding RNAs (ncRNA). Among these, micro-RNAs (miRNAs) belong to the short ncRNA class (22–25 nucleotides in length), with approximately 2500 miRNA genes encoded within the human genome. From a therapeutic perspective, there is interest in exploiting miRNA as biomarkers of disease progression and response to treatments, as well as miRNA mimics/repressors as novel medicines. miRNA have emerged as an important class of RNA master regulators with important roles identified in the pathogenesis of atherosclerotic cardiovascular disease. Atherosclerosis is characterized by a chronic inflammatory build-up, driven largely by low-density lipoprotein cholesterol accumulation within the artery wall and vascular injury, including endothelial dysfunction, leukocyte recruitment and vascular remodelling. Conventional therapy focuses on lifestyle interventions, blood pressure-lowering medications, high-intensity statin therapy and antiplatelet agents. However, a significant proportion of patients remain at increased risk of cardiovascular disease. This continued cardiovascular risk is referred to as residual risk. Hence, a new drug class targeting atherosclerosis could synergise with existing therapies to optimise outcomes. Here, we review our current understanding of the role of ncRNA, with a focus on miRNA, in the development and progression of atherosclerosis, highlighting novel biological mechanisms and therapeutic avenues.

The Role of High-Density Lipoprotein Cholesterol in 2022

PURPOSE OF THE REVIEW

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

RECENT FINDINGS

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