Effect of Quercetin on Atherosclerosis Based on Expressions of ABCA1, LXR-α and PCSK9 in ApoE-/- Mice

Prospect of research on anti-atherosclerosis effect of main components of traditional Chinese medicine Yiqi Huoxue Huatan recipe through gut microbiota: A review

The incidence and mortality rates of cardiovascular diseases are on the rise globally, posing a severe threat to human health. Atherosclerosis (AS) is considered a multi-factorial inflammatory disease and the main pathological basis of cardiovascular and cerebrovascular diseases, as well as the leading cause of death. Dysbiosis of the gut microbiota can induce and exacerbate inflammatory reactions, accelerate metabolic disorders and immune function decline, and affect the progression and prognosis of AS-related diseases. The Chinese herbal medicine clinicians frequently utilize Yiqi Huoxue Huatan recipe, an effective therapeutic approach for the management of AS. This article reviews the correlation between the main components of Yiqi Huoxue Huatan recipe and the gut microbiota and AS to provide new directions and a theoretical basis for the prevention and treatment of AS.

Beneficial effects of flavonoids on animal models of atherosclerosis: A systematic review and meta-analysis

Atherosclerosis is the main cause of cardiovascular diseases that seriously endanger human health. The existing treatment drugs are effective, but they have some side effects. Accumulating evidence suggests that flavonoids have attracted wide attention due to their multiple cardioprotective effects and fewer side effects. PubMed, Web of Science database, Embase, and Cochrane Library were searched for studies evaluating the effects of flavonoids against atherosclerosis. 119 studies published from August 1954 to April 2023 were included. Random-effects models were performed for synthesis. Compared with the control group, flavonoids significantly reduced longitudinal and cross-sectional plaque area. The findings indicated that flavonoids significantly reduced the concentrations of serum TC, TG, and LDL-C and increased serum HDL-C concentrations. Besides, flavonoids reduced the levels of circulating pro-inflammatory factors, including TNF-α, IL-1β, and IL-6, and increased the serum IL-10 level. This study provides evidence for the potential cardiovascular benefits of flavonoids.

Cardioprotective effect of the quercetin on cardiovascular remodeling and atherosclerosis in rodents fed a high-fat diet: A systematic review

Cardiovascular diseases (CVD) are the leading cause of death globally, estimated at 17.9 million premature deaths. Several risk factors contribute to the development of CVD, including unhealthy diet rich in saturated fat. Quercetin (Q) is a important natural flavonoid with cardioprotective effect. However, it is crucial to understand and clarify which dosages and intervention times quercetin promotes better cardioprotective effects when exposed to a High-Fat Diet (HFD). We aim was to carry out a review to identify and compare experimental studies that investigated the quercetin effect on cardiac parameters in rodents fed a HFD. This literature search was performed through the specialized databases PubMed, Embase, Web of Science and Lilacs in May 2022. The following information was collected and assessed: Species of animals, dietary fat content, intervention protocol (quercetin), and main results of alterations associated with cardiac change. A total of 116 articles were selected from the database and 30 articles were included in this study. The administration form of quercetin was used in the diet supplemented in 73.4% (n = 22) of the studies. The dosage ranged between 10 and 100 mg/kg, 0.01%-0.36%, and 4-8 g/kg diet. The treatment time ranged between 14 and 63 days in 48.4% studies and most of the selected studies observed changes in the: Serum concentrations of lipids (60%, n = 18) mainly decrease in TC and TG, left ventricle (LV) (16.13%, n = 5) includes attenuation of the cardiac hypertrophy; inhibition of atherosclerotic progression (32%, n = 10) with decrease in lesions and plaque formation; improvement in the expression of gene and protein associated with cardiac functionality and oxidative stress (51.6%; n = 16). Quercetin supplementation at different concentrations/doses promotes important cardioprotective effects in experimental models exposed to a HFD. The supplemented diet was shown to be the better administration option. The methodological variation presented in the articles selected in this review proves that the most appropriate intervention protocol, as well as the most effective route of administration, promotes these effects.

The association between circulatory, local pancreatic PCSK9 and type 2 diabetes mellitus: The effects of antidiabetic drugs on PCSK9

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a potent modulator of cholesterol metabolism and plays a crucial role in the normal functioning of pancreatic islets and the progression of diabetes. Islet autocrine PCSK9 deficiency can lead to the enrichment of low-density lipoprotein (LDL) receptor (LDLR) and excessive LDL cholesterol (LDL-C) uptake, subsequently impairing the insulin secretion in β-cells. Circulatory PCSK9 levels are primarily attributed to hepatocyte secretion. Notably, anti-PCSK9 strategies proposed for individuals with hypercholesterolemia chiefly target liver-derived PCSK9; however, these anti-PCSK9 strategies have been associated with the risk of new-onset diabetes mellitus (NODM). In the current review, we highlight a new direction in PCSK9 inhibition therapy strategies: screening candidates for anti-PCSK9 from the drugs used in type 2 diabetes mellitus (T2DM) treatment. We explored the association between circulating, local pancreatic PCSK9 and T2DM, as well as the relationship between PCSK9 monoclonal antibodies and NODM. We discussed the emergence of artificial and natural drugs in recent years, exhibiting dual benefits of antidiabetic activity and PCSK9 reduction, confirming that the diverse effects of these drugs may potentially impact the progression of diabetes and associated disorders, thereby introducing novel avenues and methodologies to enhance disease prognosis.

Bio-Actives from Natural Products with Potential Cardioprotective Properties: Isolation, Identification, and Pharmacological Actions of Apigenin, Quercetin, and Silibinin

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide. As a result, pharmaceutical and non-pharmaceutical interventions modifying risk factors for CVDs are a top priority of scientific research. Non-pharmaceutical therapeutical approaches, including herbal supplements, have gained growing interest from researchers as part of the therapeutic strategies for primary or secondary prevention of CVDs. Several experimental studies have supported the potential effects of apigenin, quercetin, and silibinin as beneficial supplements in cohorts at risk of CVDs. Accordingly, this comprehensive review focused critically on the cardioprotective effects/mechanisms of the abovementioned three bio-active compounds from natural products. For this purpose, we have included in vitro, preclinical, and clinical studies associated with atherosclerosis and a wide variety of cardiovascular risk factors (hypertension, diabetes, dyslipidemia, obesity, cardiac injury, and metabolic syndrome). In addition, we attempted to summarize and categorize the laboratory methods for their isolation and identification from plant extracts. This review unveiled many uncertainties which are still unexplored, such as the extrapolation of experimental results to clinical practice, mainly due to the small clinical studies, heterogeneous doses, divergent constituents, and the absence of pharmacodynamic/pharmacokinetic analyses.

Exploring the Active Compounds of Traditional Mongolian Medicine Baolier Capsule (BLEC) in Patients with Coronary Artery Disease (CAD) Based on Network Pharmacology Analysis, Molecular Docking and Experimental Validation

Objective

Baolier Capsule (BLEC) is a Traditional Mongolian Medicine comprising fifteen herbs. This study aims to illustrate the synergistic mechanism of BLEC in the treatment of Coronary Artery Disease (CAD) by using network pharmacology method, molecular docking and experimental validation.

Methods

Searching and screening the active ingredients of different herbs in BLEC and target genes related to CAD in multiple databases. Subsequently, Protein-Protein Interactions Network (PPI-Net), gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment were used to identify the key targets. AutoDock was used to verify the binding ability between the active ingredient and key target through molecular docking. Reverse Transcription-Quantitative Real-Time Polymerase Chain Reaction (RT-qPCR) was used to verify the effect of active ingredient of BLEC on the key target gene. Finally, effect of BLEC on the degree of blood lipids and atherosclerosis was validated by animal experiment.

Results

There are 144 active components and 80 CAD-related targets that are identified in BLEC in the treatment of CAD. What is more, 8 core genes were obtained by clustering and topological analysis of PPI-Net. Further, GO and KEGG analysis showed that fluid shear stress and atherosclerosis are the key pathways for BLEC to treat CAD. These results were validated by molecular docking method. In vitro, active compounds of BLEC (Quercetin, luteolin, kaempferol, naringenin, tanshinone IIA, β-carotene, 7-O-methylisomucronulatol, piperine, isorhamnetin and Xyloidone) can inhibit 8 core gene (AKT1, EGFR, FOS, MAPK1, MAPK14, STAT3, TP53 and VEGFA) expression. Moreover, BLEC not only improve blood lipid levels but also inhibit the development of atherosclerosis in ApoE-knockout mice.

Conclusion

Our research first revealed the basic pharmacological effects and related mechanisms of in the treatment of CAD. The predicted results provide some theoretical support for BLEC or its important active ingredients to treat CAD.

Recent advances of traditional Chinese medicine for the prevention and treatment of atherosclerosis

ETHNOPHARMACOLOGICAL RELEVANCE

Atherosclerosis (AS) is a common systemic disease with increasing morbidity and mortality worldwide. Traditional Chinese medicine (TCM) with characteristics of multiple pathways and targets, presents advantages in the diagnosis and treatment of atherosclerosis.

AIM OF THE STUDY

With the modernization of TCM, the active ingredients and molecular mechanisms of TCM for AS treatment have been gradually revealed. Therefore, it is necessary to examine the existing studies on TCM therapies aimed at regulating AS over the past two decades.

MATERIALS AND METHODS

Using "atherosclerosis" and "Traditional Chinese medicine" as keywords, all relevant TCM literature published in the last 10 years was collected from electronic databases (such as Elsevier, Springer, PubMed, CNKI, and Web of Science), books and papers until March 2022, and the critical information was statistically analyzed.

RESULTS

In this review, we highlighted extracts of 8 single herbs, a total of 41 single active ingredients, 20 TCM formulae, and 25 patented drugs, which were described with chemical structure, source, model, efficacy and potential mechanism.

CONCLUSION

We summarized the cytopathological basis for the development of atherosclerosis involving vascular endothelial cells, macrophages and vascular smooth muscle cells, and categorically elaborated the medicinal TCM used for AS, all of which provide the current evidence on the better management of atherosclerosis by TCM.

Potential Role of Quercetin Glycosides as Anti-Atherosclerotic Food-Derived Factors for Human Health

Quercetin is a monomeric polyphenol of plant origin that belongs to the flavonol-type flavonoid subclass. Extensive studies using cultured cells and experimental model animals have demonstrated the anti-atherosclerotic effects of dietary quercetin in relation to the prevention of cardiovascular disease (CVD). As quercetin is exclusively present in plant-based foods in the form of glycosides, this review focuses on the bioavailability and bioefficacy of quercetin glycosides in relation to vascular health effects. Some glucose-bound glycosides are absorbed from the small intestine after glucuronide/sulfate conjugation. Both conjugated metabolites and deconjugated quercetin aglycones formed by plasma β-glucuronidase activity act as food-derived anti-atherogenic factors by exerting antioxidant, anti-inflammatory, and plasma low-density lipoprotein cholesterol-lowering effects. However, most quercetin glycosides reach the large intestine, where they are subject to gut microbiota-dependent catabolism resulting in deglycosylated aglycone and chain-scission products. These catabolites also affect vascular health after transfer into the circulation. Furthermore, quercetin glycosides may improve gut microbiota profiles. A variety of human cohort studies and intervention studies support the idea that the intake of quercetin glycoside-rich plant foods such as onion helps to prevent CVD. Thus, quercetin glycoside-rich foods offer potential benefits in terms of cardiovascular health and possible clinical applications.

Alterations of HDL's to piHDL's Proteome in Patients with Chronic Inflammatory Diseases, and HDL-Targeted Therapies

Chronic inflammatory diseases, such as rheumatoid arthritis, steatohepatitis, periodontitis, chronic kidney disease, and others are associated with an increased risk of atherosclerotic cardiovascular disease, which persists even after accounting for traditional cardiac risk factors. The common factor linking these diseases to accelerated atherosclerosis is chronic systemic low-grade inflammation triggering changes in lipoprotein structure and metabolism. HDL, an independent marker of cardiovascular risk, is a lipoprotein particle with numerous important anti-atherogenic properties. Besides the essential role in reverse cholesterol transport, HDL possesses antioxidative, anti-inflammatory, antiapoptotic, and antithrombotic properties. Inflammation and inflammation-associated pathologies can cause modifications in HDL's proteome and lipidome, transforming HDL from atheroprotective into a pro-atherosclerotic lipoprotein. Therefore, a simple increase in HDL concentration in patients with inflammatory diseases has not led to the desired anti-atherogenic outcome. In this review, the functions of individual protein components of HDL, rendering them either anti-inflammatory or pro-inflammatory are described in detail. Alterations of HDL proteome (such as replacing atheroprotective proteins by pro-inflammatory proteins, or posttranslational modifications) in patients with chronic inflammatory diseases and their impact on cardiovascular health are discussed. Finally, molecular, and clinical aspects of HDL-targeted therapies, including those used in therapeutical practice, drugs in clinical trials, and experimental drugs are comprehensively summarised.

Potential Pharmaceutical Applications of Quercetin in Cardiovascular Diseases

Quercetin, as a member of flavonoids, has emerged as a potential therapeutic agent in cardiovascular diseases (CVDs) in recent decades. In this comprehensive literature review, our goal was a critical appraisal of the pathophysiological mechanisms of quercetin in relation to the classical cardiovascular risk factors (e.g., hyperlipidemia), atherosclerosis, etc. We also assessed experimental and clinical data about its potential application in CVDs. Experimental studies including both in vitro methods and in vivo animal models mainly outline the following effects of quercetin: (1) antihypertensive, (2) hypolipidemic, (3) hypoglycemic, (4) anti-atherosclerotic, and (5) cardioprotective (suppressed cardiotoxicity). From the clinical point of view, there are human studies and meta-analyses implicating its beneficial effects on glycemic and lipid parameters. In contrast, other human studies failed to demonstrate consistent favorable effects of quercetin on other cardiometabolic risk factors such as MS, obesity, and hypertension, underlying the need for further investigation. Analyzing the reason of this inconsistency, we identified significant drawbacks in the clinical trials’ design, while the absence of pharmacokinetic/pharmacodynamic tests prior to the studies attenuated the power of clinical results. Therefore, additional well-designed preclinical and clinical studies are required to examine the therapeutic mechanisms and clinical efficacy of quercetin in CVDs.

A comprehensive review of beetroot (Beta vulgaris L.) bioactive components in the food and pharmaceutical industries

Beetroot is rich in various bioactive phytochemicals, which are beneficial for human health and exert protective effects against several disease conditions like cancer, atherosclerosis, etc. Beetroot has various therapeutic applications, including antioxidant, antibacterial, antiviral, and analgesic functions. Besides the pharmacological effects, food industries are trying to preserve beetroots or their phytochemicals using various food preservation methods, including drying and freezing, to preserve their antioxidant capacity. Beetroot is a functional food due to valuable active components such as minerals, amino acids, phenolic acid, flavonoid, betaxanthin, and betacyanin. Due to its stability, nontoxic and non-carcinogenic and nonpoisonous capabilities, beetroot has been used as an additive or preservative in food processing. Beetroot and its bioactive compounds are well reported to possess antioxidant, anti-inflammatory, antiapoptotic, antimicrobial, antiviral, etc. In this review, we provided updated details on (i) food processing, preservation and colorant methods using beetroot and its phytochemicals, (ii) synthesis and development of several nanoparticles using beetroot and its bioactive compounds against various diseases, (iii) the role of beetroot and its phytochemicals under disease conditions with molecular mechanisms. We have also discussed the role of other phytochemicals in beetroot and their health benefits. Recent technologies in food processing are also updated. We also addressed on molecular docking-assisted biological activity and screening for bioactive chemicals. Additionally, the role of betalain from different sources and its therapeutic effects have been listed. To the best of our knowledge, little or no work has been carried out on the impact of beetroot and its nanoformulation strategies for phytocompounds on antimicrobial, antiviral effects, etc. Moreover, epigenetic alterations caused by phytocompounds of beetroot under several diseases were not reported much. Thus, extensive research must be carried out to understand the molecular effects of beetroot in the near future.

Cyclodextrin-mediated conjugation of macrophage and liposomes for treatment of atherosclerosis

Current pharmacological treatments of atherosclerosis often target either cholesterol management or inflammation management, to inhibit atherosclerotic progression, but cannot lead to direct plaque lysis and atherosclerotic regression, partly due to the poor accumulation of medicine in the atherosclerotic plaques. Due to enhanced macrophage recruitment during atheromatous plaque progression, a facilely macrophage-liposome conjugate was constructed for targeted anti-atherosclerosis therapy via synergistic plaque lysis and inflammation alleviation. Endogenous macrophage is utilized as drug-transporting cell, upon membrane-modification with β-cyclodextrin (β-CD) derivative to form β-CD decorated macrophage (CD-MP). Adamantane (ADA) modified quercetin (QT)-loaded liposome (QT-NP), can be conjugated to CD-MP via host-guest interactions between β-CD and ADA to construct macrophage-liposome conjugate (MP-QT-NP). Thus, macrophage carries liposome "hand-in-hand" to significantly increase the accumulation of anchored QT-NP in the aorta plaque in response to the plaque inflammation. In addition to anti-inflammation effects of QT, MP-QT-NP efficiently regresses atherosclerotic plaques from both murine aorta and human carotid arteries via CD-MP mediated cholesterol efflux, due to the binding of cholesterol by excess membrane β-CD. Transcriptome analysis of atherosclerotic murine aorta and human carotid tissues reveal that MP-QT-NP may activate NRF2 pathway to inhibit plaque inflammation, and simultaneously upregulate liver X receptor to promote cholesterol efflux.

Network Pharmacology-Based Strategy Combined with Molecular Docking and in vitro Validation Study to Explore the Underlying Mechanism of Huo Luo Xiao Ling Dan in Treating Atherosclerosis

Background

Huo Luo Xiao Ling Dan (HLXLD), a famous Traditional Chinese Medicine (TCM) classical formula, possesses anti-atherosclerosis (AS) activity. However, the underlying molecular mechanisms remain obscure.

Aim

The network pharmacology approach, molecular docking strategy, and in vitro validation experiment were performed to explore the potential active compounds, key targets, main signaling pathways, and underlying molecular mechanisms of HLXLD in treating AS.

Methods

Several public databases were used to search for active components and targets of HLXLD, as well as AS-related targets. Crucial bioactive ingredients, potential targets, and signaling pathways were acquired through bioinformatics analysis. Subsequently, the molecular docking strategy and molecular dynamics simulation were carried out to predict the affinity and stability of active compounds and key targets. In vitro cell experiment was performed to verify the findings from bioinformatics analysis.

Results

A total of 108 candidate compounds and 321 predicted target genes were screened. Bioinformatics analysis suggested that quercetin, dihydrotanshinone I, pelargonidin, luteolin, guggulsterone, and β-sitosterol may be the main ingredients. STAT3, HSP90AA1, TP53, and AKT1 could be the key targets. MAPK signaling pathway might play an important role in HLXLD against AS. Molecular docking and molecular dynamics simulation results suggested that the active compounds bound well and stably to their targets. Cell experiments showed that the intracellular accumulation of lipid and increased secretory of TNF-α, IL-1β, and MCP-1 in ox-LDL treated RAW264.7 cells, which can be significantly suppressed by pretreating with dihydrotanshinone I. The up-regulation of STAT3, ERK, JNK, and p38 phosphorylation induced by ox-LDL can be inhibited by pretreating with dihydrotanshinone I.

Conclusion

Our findings comprehensively demonstrated the active compounds, key targets, main signaling pathways, and underlying molecular mechanisms of HLXLD in treating AS. These findings would provide a scientific basis for the study of the complex mechanisms underlying disease and drug action.

Potential dual inhibitors of PCSK-9 and HMG-R from natural sources in cardiovascular risk management

Atherosclerotic cardiovascular disease (ASCVD) stands amongst the leading causes of mortality worldwide and has attracted the attention of world's leading pharmaceutical companies in order to tackle such mortalities. The low-density lipoprotein-cholesterol (LDL-C) is considered the most prominent biomarker for the assessment of ASCVD risk. Distinct inhibitors of 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMG-R), the chief hepatic cholesterogenic enzyme, are being used since last seven decades to manage hypercholesterolemia. On the other hand, discovery and the association of proprotein convertase subtilisin/kexin type-9 (PCSK-9) with increased ASCVD risk have established PCSK-9 as a novel therapeutic target in cardiovascular medicine. PCSK-9 is well reckoned to facilitate the LDL-receptor (LDL-R) degradation and compromised LDL-C clearance leading to the arterial atherosclerotic plaque formation. The currently available HMG-R inhibitors (statins) and PCSK-9 inhibitors (siRNA, anti-sense oligonucleotides, and monoclonal antibodies) have shown great promises in achieving LDL-C lowering goals, however, their life long prescriptions have raised significant concerns. These deficits associated with the synthetic HMG-R and PCSK-9 inhibitors called for the discovery of alternative therapeutic candidates with potential dual HMG-R and PCSK-9 inhibitory activities from natural origins. Therefore, this report firstly describes the mechanistic insights into the cholesterol homeostasis through HMG-R, PCSK-9, and LDL-R functionality and then compiles the pharmacological effects of natural secondary metabolites with special emphasis on their dual HMG-R and PCSK-9 inhibitory action. In conclusion, various natural products exhibit atheroprotective effects via targeting HMG-R and PCSK-9 activities and lipoprotein metabolism, however, further clinical assessments are still warranted prior their approval for ASCVD risk management in hypercholesterolemic patients.

Crocin ameliorates atherosclerosis by promoting the reverse cholesterol transport and inhibiting the foam cell formation via regulating PPARγ/LXR-α

Crocin (CRO) is feasible in alleviating atherosclerosis (AS), the mechanism of which was therefore explored in the study. High-fat diet (HFD)-induced apolipoprotein E-deficient (ApoE^−/−) mice and lysophosphatidic acid (LPA)-treated macrophages received CRO treatment. Treated macrophage viability was determined via MTT assay. In both murine and macrophage, the lipid level and total Cholesterol/Cholesteryl l Ester (TC/CE) levels were quantified by oil-red-O staining and ELISA, respectively. Lipid droplet, aortic plaque formation and collagen deposition were detected via Oil-red-O staining, hematoxylin–eosin staining and Masson staining, respectively. Liver X Receptor-α (LXR-α), Peroxisome Proliferator-Activated Receptor γ (PPARγ), CD68, PCSK9, CD36, ATP Binding Cassette Subfamily A Member 1 (ABCA1), phosphorylated (p)-AKT, and AKT expressions were detected via Western blot, the former three also being detected using Immunohistochemistry and the first being measured by qRT-PCR. CRO decreased HFD-induced weight gain, ameliorated the abnormal serum lipid levels of HFD-treated mice, and inhibited aortic plaque formation and lipid deposition, and increased collagen fibers, with upregulated high-density lipoprotein-cholesterol (HDL-C) and downregulated TC and low-density lipoprotein-cholesterol (LDL-C). CRO alleviated the HFD-induced upregulations of CD68, PCSK9 and CD36 as well as downregulations of PPARγ/LXR-α, ABCA1 and AKT phosphorylation. In LPA-treated macrophages, CRO alone exerted no effect on the viability yet inhibited the lipid droplets formation and downregulated TC/CE levels. Silent LXR-α reversed the effect of CRO on the lipid droplets formation and levels of lipid metabolism-related factors. CRO ameliorated AS by inhibiting foam cells formation and promoting reverse cholesterol transport via PPARγ/LXR-α.

Effects of DHA dietary intervention on hepatic lipid metabolism in apolipoprotein E-deficient and C57BL/6J wild-type mice

Lipid metabolic disorder occurs when ApoE gene is deficient. However, the role of Docosahexaenoic acid (DHA) in relieving hepatic lipid metabolic disorder in apolipoprotein E-deficient (ApoE -/-) mice remains unknown. We fed 3-month-old C57BL/6J wild-type (C57 wt) and ApoE -/- mice respectively with normal or DHA fortified diet for 5 months. We found ApoE gene deficiency caused hepatic lipid deposition and increased lipid levels in plasma and liver. Hepatic gene expression of SRB1, CD36 and FABP5 in ApoE -/- mice, protein expression of HMGCR, LRP1 in C57 wt mice and protein expression of LRP1 in ApoE -/- mice increased after DHA intervention. In DHA-fed ApoE -/- mice, LXRα/β and PPARα protein expression down-regulated in cytoplasm, but LXRα/β protein expression up-regulated in nucleus. DHA treatment decreased RXRα and RXRβ expression in C57 wt and ApoE -/- female mice. Deletion of ApoE gene caused lipid metabolism disorder in liver of mice. DHA treatment efficiently meliorated lipid metabolism caused by ApoE deficient through the regulation of gene and protein expressions of molecules involved in liver fatty acids transport and lipid metabolism.

Bioactivity of Dietary Polyphenols: The Role in LDL-C Lowering

Cardiovascular diseases are the leading causes of the death around the world. An elevation of the low-density lipoprotein cholesterol (LDL-C) level is one of the most important risk factors for cardiovascular diseases. To achieve optimal plasma LDL-C levels, clinal therapies were investigated which targeted different metabolism pathways. However, some therapies also caused various adverse effects. Thus, there is a need for new treatment options and/or combination therapies to inhibit the LDL-C level. Dietary polyphenols have received much attention in the prevention of cardiovascular diseases due to their potential LDL-C lowering effects. However, the effectiveness and potential mechanisms of polyphenols in lowering LDL-C is not comprehensively summarized. This review focused on dietary polyphenols that could reduce LDL-C and their mechanisms of action. This review also discussed the limitations and suggestions regarding previous studies.

Liver X receptors conserve the therapeutic target potential for the treatment of rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic multi-system autoimmune disease with extremely complex pathogenesis. Significantly altered lipid paradox related to the inflammatory burden is reported in RA patients, inducing 50% higher cardiovascular risks. Recent studies have also demonstrated that lipid metabolism can regulate many functions of immune cells in which metabolic pathways have altered. The nuclear liver X receptors (LXRs), including LXRα and LXRβ, play a central role in regulating lipid homeostasis and inflammatory responses. Undoubtedly, LXRs have been considered as an attractive therapeutic target for the treatment of RA. However, there are some contradictory effects of LXRs agonists observed in previous animal studies where both pro-inflammatory role and anti-inflammatory role were revealed for LXRs activation in RA. Therefore, in addition to updating the knowledge of LXRs as the prominent regulators of lipid homeostasis, the purpose of this review is to summarize the effects of LXRs agonists in RA-associated immune cells, to explore the underlying reasons for the contradictory therapeutic effects of LXRs agonists observed in RA animal models, and to discuss future strategy for the treatment of RA with LXRs modulators.

Therapeutic Potential of Quercetin to Alleviate Endothelial Dysfunction in Age-Related Cardiovascular Diseases

The vascular endothelium occupies a catalog of functions that contribute to the homeostasis of the cardiovascular system. It is a physically active barrier between circulating blood and tissue, a regulator of the vascular tone, a biochemical processor and a modulator of coagulation, inflammation, and immunity. Given these essential roles, it comes to no surprise that endothelial dysfunction is prodromal to chronic age-related diseases of the heart and arteries, globally termed cardiovascular diseases (CVD). An example would be ischemic heart disease (IHD), which is the main cause of death from CVD. We have made phenomenal advances in treating CVD, but the aging endothelium, as it senesces, always seems to out-run the benefits of medical and surgical therapies. Remarkably, many epidemiological studies have detected a correlation between a flavonoid-rich diet and a lower incidence of mortality from CVD. Quercetin, a member of the flavonoid class, is a natural compound ubiquitously found in various food sources such as fruits, vegetables, seeds, nuts, and wine. It has been reported to have a wide range of health promoting effects and has gained significant attention over the years. A growing body of evidence suggests quercetin could lower the risk of IHD by mitigating endothelial dysfunction and its risk factors, such as hypertension, atherosclerosis, accumulation of senescent endothelial cells, and endothelial-mesenchymal transition (EndoMT). In this review, we will explore these pathophysiological cascades and their interrelation with endothelial dysfunction. We will then present the scientific evidence to quercetin's anti-atherosclerotic, anti-hypertensive, senolytic, and anti-EndoMT effects. Finally, we will discuss the prospect for its clinical use in alleviating myocardial ischemic injuries in IHD.

Rare earth element lanthanum protects against atherosclerosis induced by high-fat diet via down-regulating MAPK and NF-κB pathways

Rare earth elements, which are extensively used in environmental protection, medicine, food, aerospace and other fields, have attracted widespread attention in recent years. However, the effect on atherosclerosis and its biological mechanism remains unclear. To elucidate these problems, here we performed a study that Apolipoprotein E-deficient mice were fed with high-fat diet to promote the development of atherosclerosis, meanwhile, mice were received 0.1, 0.2, 1.0, 2.0 mg/kg lanthanum nitrate (La(NO₃)₃) for 12 weeks. The results showed that La(NO₃)₃ prominently inhibited aorta morphological alternations by histopathological examination. Meanwhile, La(NO₃)₃ regulated serum lipids, including reducing total cholesterol and increasing high-density lipoprotein. Moreover, the oxidative stress was alleviated by La(NO₃)₃ intervention through enhancing superoxide dismutase and glutathione, and decreasing malondialdehyde levels. In addition, enzyme-linked immunosorbent assay analysis showed La(NO₃)₃ could ameliorate the dysfunction of vascular endothelium with declined endothelin-1 and increased prostacyclin. Furthermore, Western blot analysis indicated that La(NO₃)₃ significantly down-regulated inflammation-mediated proteins including phosphorylated p38 mitogen-activated protein kinases (p-p38 MAPK), monocyte chemo-attractant protein, intercellular adhesion molecule-1, nuclear factor-kappa B p65 (NF-κB p65), tumor necrosis factor-α, interleukin-6 and interleukin-1β, whereas up-regulated the inhibitor of NF-κB protein. In conclusion, La(NO₃)₃ ameliorates atherosclerosis by regulating lipid metabolism, oxidative stress, endothelial dysfunction and inflammatory response in mice. The potential mechanism associates with the inhibition of MAPK and NF-κB signaling pathways.

Flavonoids in adipose tissue inflammation and atherosclerosis: one arrow, two targets

Flavonoids are polyphenolic compounds naturally occurring in fruits and vegetables, in addition to beverages such as tea and coffee. Flavonoids are emerging as potent therapeutic agents for cardiovascular as well as metabolic diseases. Several studies corroborated an inverse relationship between flavonoid consumption and cardiovascular disease (CVD) or adipose tissue inflammation (ATI). Flavonoids exert their anti-atherogenic effects by increasing nitric oxide (NO), reducing reactive oxygen species (ROS), and decreasing pro-inflammatory cytokines. In addition, flavonoids alleviate ATI by decreasing triglyceride and cholesterol levels, as well as by attenuating inflammatory mediators. Furthermore, flavonoids inhibit synthesis of fatty acids and promote their oxidation. In this review, we discuss the effect of the main classes of flavonoids, namely flavones, flavonols, flavanols, flavanones, anthocyanins, and isoflavones, on atherosclerosis and ATI. In addition, we dissect the underlying molecular and cellular mechanisms of action for these flavonoids. We conclude by supporting the potential benefit for flavonoids in the management or treatment of CVD; yet, we call for more robust clinical studies for safety and pharmacokinetic values.

Therapeutic Potential of Quercetin as an Antiatherosclerotic Agent in Atherosclerotic Cardiovascular Disease: A Review

Atherosclerotic cardiovascular disease (ASCVD) is one of the diseases with the highest morbidity and mortality globally. It causes a huge burden on families and caregivers and high costs for medicine and surgical interventions. Given expensive surgeries and failures of most conventional treatments, medical community tries to find a more cost-effective cure. Thus, attentions have been primarily focused on food or herbs. Quercetin (Qu) extracted from food, a flavonoid component, develops potentials of alternative or complementary medicine in atherosclerosis. Due to the wide range of health benefits, researchers have considered to apply Qu as a natural compound in therapy. This review is aimed to identify the antiatherosclerosis functions of Qu in treating ASCVD such as anti-inflammatory, antioxidant properties, effects on endothelium-dependent vasodilation, and blood lipid-lowering.