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Abstract: Sphingomyelin (SM) is a dominant sphingolipid in membranes of mammalian cells and this lipid class is specifically enriched in the plasma membrane, the endocytic recycling compartment, and the trans Golgi network. The distribution of SM and cholesterol among cellular compartments correlate. Sphingolipids have extensive hydrogen-bonding capabilities which together with their saturated nature facilitate the formation of sphingolipid and SM-enriched lateral domains in membranes. Cholesterol prefers to interact with SMs and this interaction has many important functional consequences. In this review, the synthesis, regulation, and intracellular distribution of SMs are discussed. The many direct roles played by membrane SM in various cellular functions and processes will also be discussed. These include involvement in the regulation of endocytosis and receptor-mediated ligand uptake, in ion channel and G-protein coupled receptor function, in protein sorting, and functioning as receptor molecules for various bacterial toxins, and for non-bacterial pore-forming toxins. SM is also an important constituent of the eye lens membrane, and is believed to participate in the regulation of various nuclear functions. SM is an independent risk factor in the development of cardiovascular disease, and new studies have shed light on possible mechanism behind its role in atherogenesis. [Copyright &y& Elsevier]

Abstract: Objectives: Dietary modifications including healthy eating constitute one of the first line strategies for prevention and treatment of cardiovascular disease (CVD) risk factors including high cholesterol and atherosclerosis. The purpose of the present study was to investigate the potential cardiovascular benefits of wild rice in male and female LDL–receptor–deficient (LDLr-KO) mice. Methods: Wild rice was used to create a semi-synthetic diet containing approximately 60% of total energy from carbohydrate. Two other experimental diets were similar in macronutrient composition, but containing either white rice or commercial carbohydrate sources. All diets were supplemented with 0.06% (w/w) dietary cholesterol. The mice were divided into six experimental groups and fed with these diets over 24 weeks. Results: Consumption of wild rice significantly reduced the size and severity of atherosclerotic lesions in the aortic roots of male and female mice by 71 and 61% respectively, compared to the control group of the same gender. This effect was associated with significant reductions of plasma cholesterol levels by 15 and 40%, low density lipoprotein (LDL) levels by 12 and 42%, and very low density lipoprotein (VLDL) levels by 35 and 75% respectively, in male and female mice compared to the control group of the same gender. Increased fecal cholesterol excretion of up to 34% was also noted, compared to the control group of the same gender. However, the antiatherogenic effect of wild rice was not associated with increased superoxide dismutase (SOD) and catalase (CAT) activities. Conclusion: Current data suggest that cholesterol-lowering effects of wild rice may be the main factor for the prevention of atherogenesis in LDLr-KO mice. Additional studies are needed to understand the mechanism of action. [Copyright &y& Elsevier]

Abstract: Atherosclerosis is a chronic inflammatory disease of the arterial wall where the accumulation of foam cells, lipids, calcium, and cellular debris leads to large fibrofatty atheromatous plaques narrowing the arterial lumen. As the principal cause of human deaths in the world, the pathogenesis of atherosclerosis has been extensively studied, as well as lipid and lipoprotein metabolism, across species. Important aspects of the disease were first investigated experimentally in a wide array of animal models, including laboratory avian and mammalian species also kept as companion pets. Although the disease is primarily a significant clinical entity in avian patients, the wealth of information obtained from companion exotic mammals is of interest to understand the complex comparative pathogenesis of atherosclerotic lesions. This review presents the current concepts of atherogenesis and lipoprotein metabolism followed by a brief overview of species peculiarities as it relates to the experimental reproduction of the disease. This overview should provide interesting insight on atherosclerosis, which spontaneously or experimentally affects many zoological companion species commonly seen by veterinarians. [Copyright &y& Elsevier]

Prerequisite to atherogenesis is low-density lipoprotein (LDL) cholesterol transport from the blood into the artery wall across its endothelial cell (EC) lining. Whereas most EC junctions are tight enough to preclude LDL passage, some (≈1/2000-6000) rare ECs have temporarily-widened junctions (typically ≈10-5 of the problem's radial scale) that allow passage of large molecular aggregates like LDL. In a purely diffusive transport model, Laplace's equation describes the steady tracer profile throughout the two major subendothelial wall layers, connected by matching conditions. In a diffusive and transmural-pressure-driven advective transport model, Laplaces equation describes the steady pressure distribution in the wall, whose gradient is proportional to the advecting velocity. Both problems yield the same boundary value problem that has mixed Dirichlet/ Robin boundary conditions. We construct a linear system of integral equations that approximates the series expansion coefficients of the problem solution. We prove existence/convergence of this solution using the contraction mapping theorem and its uniqueness using Miranda's theorem. The analytical construction method yields a numerical calculation algorithm. Our analysis supports a surprising result that the series solutions convergence rate increases as the ratio (≈10-5) of leaky junction width to mean half-distance between neighboring leaky cells increases. Numerical results agree well with previous ad hoc numerical methods. The subendothelial intima exhibits boundary layer scale separation. Calculations show that the solution spike just beneath the leak is by far the region most sensitive to calculation accuracy. Since these models posit all LDL wall entry through these widened junctions, solution accuracy is particularly critical there. [ABSTRACT FROM AUTHOR]

General tendencies in the regulation of gene expression during atherogenesis were investigated using correlation analysis for 34 mRNA species of several functional groups. The contents of mRNA were measured by quantitative PCR in samples of human aortal intima containing no lesions or atherosclerotic lesions of types I (initial lesions), II (fatty streaks), and Va (fibroatheromas). The coupling between mRNA contents in lesions and the same mRNAs in intact tissue was found to descend in the course of the disease progression. The data are in accordance with the opinion that successive morphologic types of atherosclerotic lesions correspond to steps of atherogenesis. In addition, the contents of individual mRNA species could correlate with each other within the given sample type, the extent of this coupling rising along with the disease progression. The exception from this rule was a collapse in coupling for several functional groups of mRNA in lesions of type I. This collapse could indicate special position of these lesions in pathogenesis. Statistically significant correlations between mRNAs found in samples of all four types comprised in total about 50% of all possible correlations. 66% of these correlations were conservative, i.e. observed in at least two sample types. By coupling-strength, the studied mRNAs could be divided into four clusters whose composition significantly varied along with the disease progression. The disease progression was also associated with decline in number of regulatory factors that determine coordination in expression of the analyzed genes. [ABSTRACT FROM AUTHOR]

Intermittent hypoxia (IH) is a hallmark feature in obstructive sleep apnea (OSA) which is increasingly recognized as an independent risk factor for atherosclerosis. Oxidative stress, inflammation, and cell apoptosis are major pathological events initiating or accelerating atherogenesis. This study addressed whether IH would affect these proatherogenic factors in endothelial cells and the mechanistic pathways involved. EA.hy926 cells were exposed to intermittent normoxia or IH for different numbers of cycles (32, 64, or 96). IH exposure time-dependently raised cellular GSSG/GSH ratio, increased production of IL-6 and IL-8, and accelerated cell apoptosis and death, concurrent with activation of NF-κB and inhibition of Nrf2/HO-1 pathways. At 64 cycles, inhibition of NF-κB attenuated IH-induced cellular oxidative stress and accumulation of inflammatory cytokines in cell culture medium but aggravated IH-induced cell apoptosis, while stimulation of HO-1 suppressed IH-induced cellular oxidative stress and cell apoptosis without affecting accumulation of inflammatory cytokines in cell culture medium. We demonstrated that early stage of exposure to IH-induced oxidative and inflammatory stresses leading to acceleration of cell apoptosis via NF-κB and Nrf2/HO-1 pathways in endothelial cells, suggesting the potential mechanisms for IH-induced vascular pathogenesis, in resemblance to OSA. [ABSTRACT FROM AUTHOR]

Abstract: The immunoglobulin superfamily member EMMPRIN (CD147) plays an important role in a number of organ systems, including the cardiovascular system. Here we review the contemporary understanding of EMMPRIN and EMMPRIN-associated sequelae in the course of atherosclerosis. A significant body of data documents the pivotal role of EMMPRIN in the complex processes of atherogenesis, atheroprogression, and acute atherosclerothrombosis, a role that goes beyond that of a mere marker of inflammation. [Copyright &y& Elsevier]

It is recommended that individuals with diabetes restrict their dietary sodium intake. However, although salt intake is correlated with BP (blood pressure), it also partly determines the activation state of the RAAS (renin- angiotensin-aldosterone system), a key mediator of diabetes-associated atherosclerosis. apoE KO (apolipoprotein E knockout) mice were allocated for the induction of diabetes with streptozotocin or citrate buffer (controls) and further randomized to isocaloric diets containing 0.05 %, 0.3% or 3.1% sodium with or without the ACEi [ACE (angiotensin-converting enzyme) inhibitor] perindopril. After 6 weeks of study, plaque accumulation was quantified and markers of atherogenesis were assessed using RT-PCR (reverse transcription-PCR) and ELISA. The association of sodium intake and adverse cardiovascular and mortality outcomes were explored in 2648 adults with Type 1 diabetes without prior CVD (cardiovascular disease) from the FinnDiane study. A 0.05% sodium diet was associated with increased plaque accumulation in diabetic apoE KO mice, associated with activation of the RAAS. By contrast, a diet containing 3.1% sodium suppressed atherogenesis associated with suppression of the RAAS, with an efficacy comparable with ACE inhibition. In adults with Type 1 diabetes, low sodium intake was also associated with an increased risk of all-cause mortality and new-onset cardiovascular events. However, high sodium intake was also associated with adverse outcomes, leading to a J-shaped relationship overall. Although BP lowering is an important goal for the management of diabetes, off-target actions to activate the RAAS may contribute to an observed lack of protection from cardiovascular complications in patients with Type 1 diabetes with low sodium intake. [ABSTRACT FROM AUTHOR]

Background/Aims: Isoflavone genistein is a plant-derived compound structurally similar to estradiol, which behaves weakly estrogenic or anti-estrogenic in a cell- and concentration-dependent manner. Genistein has been hypothesized to have beneficial effects on vascular diseases, although the mechanism has been unclear. Here, we investigated whether genistein may play a role in atherogenesis by regulating human coronary artery endothelial cell (HCAEC) survival. Methods: HCAECs obtained from 48- to 53-year-old women (n = 3) were used and immunocytochemistry, cell proliferation assay and apoptosis assay were carried on HCAECs treated by genistein. Results: Immunocytochemistry confirmed that HCAECs in culture express predominantly ESR2. Cell proliferation assay revealed that following 72 h of genistein treatment, HCAEC proliferation decreased in a concentration-dependent (10-10 to 10-6M) manner compared to control (p < 0.01). The anti-proliferative effect of genistein is inhibited by estradiol. Genistein (10-8M) also induced a time-dependent increase in the number of apoptotic HCAECs after 24-, 48- and 72-hourtreatments as detected by TUNEL and morphological analyses. Conclusion: These findings suggest that genistein acts as an anti-proliferative agent on HCAECs. The anti-proliferative and proapoptotic effects of genistein on vascular cells underlie the proposed anti-atherogenic and cardioprotective role of genistein. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Changes in the contents of 36 mRNAs species related to lipid turnover, inflammation, metabolism and the action of sex hormones in samples of aortal intima along the 'intact tissue - lesions of type I - lesions of type II - lesions of type Va' sequence were analyzed using quantitative PCR. The expression of several mRNAs coding for components of the vesicular transfer and lipid turnover machinery was found to be resistant to atherogenesis or even decline in the course of atherogenesis. Decrease in expression was also recorded for steroid sulfatase, androgen receptor, and low density lipoprotein receptor mRNAs. However, the contents of the majority of other mRNA species increased gradually during disease progression. The earliest changes found as early as in lesions of type I were characteristic for estrogen sulfotransferase, apolipoprotein E, scavenger receptor SR-BI, collagen COL1A2, as well as chemokine CCL18 mRNAs. The contents of several mRNAs in intact tissue and atherosclerotic injuries had gender differences. Additionally, responses of two mRNAs, for aromatase and sterol regulatory element binding protein 2, to atherosclerotic lesion were also sex-differentiated. The contents of the majority of analyzed mRNAs in peripheral blood monocyte-derived macrophages were higher than in intact aorta. The correlations found in atherosclerotic lesions between mRNA species that predominant in macrophages and those expressed at comparable levels in macrophages and intact aorta or mainly in aorta suggest that the observed rise in the content of the majority of mRNAs during atherogenesis is determined by increase in expression in resident cells. The data suggest that the revealed absence of homeostatic regulation of expression of a number of genes associated with vesicular transfer and lipid turnover can serve as one of the reasons for lysosomal function insufficiency that leads to foam cell formation in atheroma. The observed sex differences in expression of a number of mRNAs suggest that estrogens in women perform their atheroprotective effects starting with predisposition to the disease and finishing with advanced stages of the pathologic process. [ABSTRACT FROM AUTHOR]

Abstract: Interactions between TNF-like Cytokine 1A (TL1A) and its receptors, death receptor-3 (DR3) and decoy receptor-3 (DcR3) may be important in atherogenesis. We hypothesized that dysregulation of this system predicts formation of new atheromatic plaques in rheumatoid arthritis (RA). Forty-five patients were prospectively followed up for 40.5±3.6months. Serum concentrations of TL1A and DcR3 were measured at baseline and carotid and femoral arteries examined by ultrasound at baseline and at the end of follow-up. Individual serum levels of TL1A correlated with the progression of carotid atheromatic plaque height (Spearman rho=0.550, p=0.003). Patients with low TL1A and undetectable DcR3 serum levels at baseline showed significantly fewer newly formed carotid plaques during the next 3.5years than the remaining patients (P=0.016). Univariate analysis showed that a “low TL1A/DcR3” immunophenotype predicted a preserved atherosclerosis profile in carotid (P=0.026), or carotid and/or femoral arteries (P=0.022). Dysregulated TL1A-induced signaling may be associated with risk for accelerated atherosclerosis in RA. [Copyright &y& Elsevier]

11β-Hydroxysteroid dehydrogenase type-1 (11β-HSD1) converts inert cortisone into active cortisol, amplifying intracellular glucocorticoid action. 11β-HSD1 deficiency improves cardiovascular risk factors in obesity but exacerbates acute inflammation. To determine the effects of 11β-HSD1 deficiency on atherosclerosis and its inflammation, atherosclerosis-prone apolipoprotein E-knockout (ApoE-KO) mice were treated with a selective 11β-HSD1 inhibitor or crossed with 11β-HSD1-KO mice to generate double knockouts (DKOs) and challenged with an atherogenic Western diet. 11β-HSD1 inhibition or deficiency attenuated atherosclerosis (74–76%) without deleterious effects on plaque structure. This occurred without affecting plasma lipids or glucose, suggesting independence from classical metabolic risk factors. KO plaques were not more inflamed and indeed had 36% less T-cell infiltration, associated with 38% reduced circulating monocyte chemoattractant protein-1 (MCP-1) and 36% lower lesional vascular cell adhesion molecule-1 (VCAM-1). Bone marrow (BM) cells are key to the atheroprotection, since transplantation of DKO BM to irradiated ApoE-KO mice reduced atherosclerosis by 51%. 11β-HSD1-null macrophages show 76% enhanced cholesterol ester export. Thus, 11β-HSD1 deficiency reduces atherosclerosis without exaggerated lesional inflammation independent of metabolic risk factors. Selective 11β-HSD1 inhibitors promise novel antiatherosclerosis effects over and above their benefits for metabolic risk factors via effects on BM cells, plausibly macrophages. [ABSTRACT FROM AUTHOR]

Background Nanoparticle processing is implicated in enhancing bioactive or nutritional compound release from raw foods. The aim of the present study was to evaluate whether different particle processing might affect the lipid-lowering activity of Dioscorea pseudojaponica ( DP ) and to investigate whether DP could be a potential functional food for prevention of atherogenesis. Its possible molecular mechanisms were also evaluated. Results The results indicated that 50 mesh-size DP (50 mesh DP ) particles exhibited stronger effects than nanoscale DP (nano DP ) particles in terms of lowering the level of serum cholesterol as well as reducing the extent of fatty liver and aortic fatty streak. Moreover, both DP particle types, particularly 50 mesh DP, significantly activated AMPK (5′-adenosine monophosphate-activated protein kinase) and deactivated ACC (acetyl- CoA carboxylase), as demonstrated by the increased levels of both enzymes in their phosphorylated form. Coincidently, high-performance liquid chromatography ( HPLC ) analysis showed a higher content ( P < 0.01) of dioscin, a known lipid-lowering compound, in 50 mesh DP than in nano DP. Conclusion These results suggest that improper processing conditions will lead to the decomposition of bioactive components in yam. They also demonstrate for the first time that the lipid-lowering mechanisms of DP may occur through the AMPK-ACC pathway. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Three different types of hen egg yolk, cage-free, organic and daily fresh, were tested for their antiatherogenic properties. Total lipids ( TL) of all hen egg yolk samples were extracted by the method of Bligh and Dyer and further separated into total polar lipids ( TPL) and total neutral lipids ( TNL) by counter current distribution chromatography. TPL and TNL were further separated by preparative thin-layer chromatography ( TLC). TL, TPL, TNL and the obtained polar and neutral lipid fractions after TLC separation were tested to determine whether they induce platelet activation or inhibit platelet activating factor ( PAF)-induced platelet activation. All three hen egg yolk TL samples possessed strong inhibitory activity against PAF-induced platelet activation that was mainly attributed to TPL, especially to PL fraction 4. Cage-free hen egg yolk exhibited the most potent anti- PAF activity in all lipid classes ( TL, TPL and TNL). Thus hen egg yolk contains PAF inhibitors that reinforce their nutritional value in terms of protection against cardiovascular diseases, since PAF is a crucial inflammatory phospholipid mediator that is implicated in the mechanism of atherogenesis. [ABSTRACT FROM AUTHOR]

The inflammation is considered to be the crucial determinants of lesion progression and plaque stability during atherogenesis. Tnfaip2 appears to be a regulator for carcinogenesis and infectious diseases. But its role in atherosclerosis is not clear. Here we first report that Tnfaip2 promotes the formation of atherosclerosis through enhancing the inflammation under oxidative stress condition. Although the endogenous expression of Tnfaip2 was upregulated under oxidative stress condition, the overexpressed Tnfaip2 could promote cells proliferation. This might result from the ability of promoting cells entering G 2 /M phase. Conversely, the cells proliferation and migration were significantly reduced in Tnfaip2 knockdown cells through inhibiting the activation of NF-κB/MAPK/Akt signaling pathways. However, the efferocytosis increased markedly due to the upregulation of "eat me" receptors, such as CD36, SR-A, and SR-B1, and the downregulation of "don't eat me" signal CD47. As a consequence, Tnfaip2 deficiency in bone marrow-derived cells inhibited atherosclerosis development in Ldlr -/- mice fed a high-fat diet accompanied by decreased inflammatory cytokines and shTnfaip2 could reduce the plaque lesions in ApoE -/- mice. These results indicate that Tnfaip2 might play an important role during atherogenesis., Competing Interests: Conflict of interest The authors declare no conflict of interest., (Copyright © 2022. Published by Elsevier Ltd.)

It was shown, that genotoxic stress can trigger endothelial disfunction and atherosclerosis, but the molecular genetic mechanisms of this process are poorly investigated. At the same time, inflammation also plays the important role in atherogenesis. This study aimed access of inflammatory marker expression in the endothelial cells exposed to alkylating mutagen mitomycin C (MMC). Primary human coronary (HCAEC) and internal thoracic artery endothelial cells (HITAEC) exposed to 500 ng/ml MMC (experimental group) and 0.9% NaCl (control) were used in this research. A gene expression profile was evaluated by quantitative reverse transcription PCR after 6 h exposure of endothelial cells to MMC (or 0.9% NaCl) followed by subsequent 24 h incubation in the mutagen-free cell growth media. The cytokine profile of endotheliocytes was studied by dot blotting. We found that MIF, IL-8, MCP-1, IP-10 and PDGFB were upregulated both in HCAEC and HITAEC, while MIP-1β release remained unchanged. TIMP-2 was upregulated in HCAEC but not in HITAEC. sTNF RI was expressed only in HCAEC. According to gene expression analysis, HCAEC exposed to MMC are characterized by the increased mRNA level of IL-8, MCP-1 and IP-10; decreased expression of TIMP-2 and no differences in the expression of MIF, MIP-1β and PDGFB compared to the control. In HITAEC, increased mRNA level of IL-8 and IP-10; decreased expression of MIF and TIMP-2, no differences in the expression of MCP-1, MIP-1β and PDGFB was shown. TNF-RI expression was not detected in both cell lines. Thus, genotoxic stress in endothelial cells induced by MMC leads to differential inflammatory response that can trigger endothelial dysfunction.

Allergic diseases are allergen-induced immunological disorders characterized by the development of type 2 immunity and IgE responses. The prevalence of allergic diseases has been on the rise alike cardiovascular disease (CVD), which affects arteries of different organs such as the heart, the kidney and the brain. The underlying cause of CVD is often atherosclerosis, a disease distinguished by endothelial dysfunction, fibrofatty material accumulation in the intima of the artery wall, smooth muscle cell proliferation, and Th1 inflammation. The opposed T-cell identity of allergy and atherosclerosis implies an atheroprotective role for Th2 cells by counteracting Th1 responses. Yet, the clinical association between allergic disease and CVD argues against it. Within, we review different phases of allergic pathology, basic immunological mechanisms of atherosclerosis and the clinical association between allergic diseases (particularly asthma, atopic dermatitis, allergic rhinitis and food allergy) and CVD. Then, we discuss putative atherogenic mechanisms of type 2 immunity and allergic inflammation including acute allergic reactions (IgE, IgG1, mast cells, macrophages and allergic mediators such as vasoactive components, growth factors and those derived from the complement, contact and coagulation systems) and late phase inflammation (Th2 cells, eosinophils, type 2 innate-like lymphoid cells, alarmins, IL-4, IL-5, IL-9, IL-13 and IL-17)., (© 2022 European Academy of Allergy and Clinical Immunology and John Wiley & Sons Ltd.)

Oxidative stress and inflammation contribute significantly to atherogenesis. We and others have demonstrated that mildly elevated serum bilirubin levels protect against coronary and peripheral atherosclerosis, most likely due to the antioxidant and anti-inflammatory activities of bilirubin. The aim of the present study was to assess serum bilirubin and the markers of oxidative stress and inflammation in both healthy subjects and patients with various forms of atherosclerosis. The study was performed in patients with premature myocardial infarction (n = 129), chronic ischemic heart disease (n = 43), peripheral artery disease (PAD, n = 69), and healthy subjects (n = 225). In all subjects, standard serum biochemistry, UGT1A1 genotypes, total antioxidant status (TAS), and concentrations of various pro- and anti-inflammatory chemokines were determined. Compared to controls, all atherosclerotic groups had significantly lower serum bilirubin and TAS, while having much higher serum high-sensitivity C-reactive protein (hsCRP) and most of the analyzed proinflammatory cytokines (p < 0.05 for all comparisons). Surprisingly, the highest inflammation, and the lowest antioxidant status, together with the lowest serum bilirubin, was observed in PAD patients, and not in premature atherosclerosis. In conclusion, elevated serum bilirubin is positively correlated with TAS, and negatively related to inflammatory markers. Compared to healthy subjects, patients with atherosclerosis have a much higher degree of oxidative stress and inflammation.

Obstructive sleep apnea (OSA) is a common sleep disorder leading to increased risk of developing cardiovascular diseases (CVDs) by supporting a low-grade chronic inflammation as one of the pathological mechanisms. The continuous positive airway pressure (CPAP) device is used as an effective treatment for moderate and severe OSA. Neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), white blood cell-mean platelet volume ratio (WMR), C-reactive protein-albumin ratio (CAR) and fibrinogen-albumin ratio (FAR) are new potential inflammatory biomarkers that are widely available and were shown to be possibly favorable screening or follow-up tools for moderate- or severe-grade OSA, as well as indirect indicators for cardiovascular risk. Our study evaluated the impact of CPAP therapy in patients with severe OSA and acceptable therapy adherence on NLR, PLR, WMR, FAR and CAR. Of 57 patients who were initially enrolled and had no exclusion criteria, 37 had a satisfactory CPAP adherence (usage of ≥4 h per night) after a minimum of 6 months of therapy. There was a statistically significant difference in NLR (2.122 ± 0.745 before therapy vs. 1.888 ± 0.735 after therapy) and FAR (86.445 ± 18.763 before therapy vs. 77.321 ± 19.133 after therapy) suggesting a positive effect of the CPAP therapy on chronic inflammatory states, thereby possibly reducing cardiovascular risk.

This study investigated the efficacy of aerobic exercise training (AET) in the prevention of dyslipidemia, insulin resistance (IR), and atherogenesis induced by severe low-sodium (LS) diet. LDL receptor knockout (LDLR KO) mice were fed a low-sodium (LS) (0.15% NaCl) or normal-sodium (NS; 1.27% NaCl) diet, submitted to AET in a treadmill, 5 times/week, 60 min/day, 15 m/min, for 90 days, or kept sedentary. Blood pressure (BP), plasma total cholesterol (TC) and triglyceride (TG) concentrations, lipoprotein profile, and insulin sensitivity were evaluated at the end of the AET protocol. Lipid infiltration, angiotensin II type 1 receptor (AT1), receptor for advanced glycation end products (RAGE), carboxymethyllysine (CML), and 4-hydroxynonenal (4-HNE) contents as well as gene expression were determined in the brachiocephalic trunk. BP and TC and gene expression were similar among groups. Compared to the NS diet, the LS diet increased vascular lipid infiltration, CML, RAGE, 4-HNE, plasma TG, LDL-cholesterol, and VLDL-TG. Conversely, the LS diet reduced vascular AT1 receptor, insulin sensitivity, HDL-cholesterol, and HDL-TG. AET prevented arterial lipid infiltration; increases in CML, RAGE, and 4-HNE contents; and reduced AT1 levels and improved LS-induced peripheral IR. The current study showed that AET counteracted the deleterious effects of chronic LS diet in an atherogenesis-prone model by ameliorating peripheral IR, lipid infiltration, CML, RAGE, 4-HNE, and AT1 receptor in the intima-media of the brachiocephalic trunk. These events occurred independently of the amelioration of plasma-lipid profile, which was negatively affected by the severe dietary-sodium restriction.

A systematic review was performed to identify all the related publications describing PCSK9 and atherogenesis biomarkers attenuation associated with a natural product and plant bioactive compounds in in vitro studies. This review emphasized the imprecision and quality of the included research rather than the detailed reporting of the results. Literature searches were conducted in Scopus, PubMed, and Science Direct from 2003 until 2021, following the Cochrane handbook. The screening of titles, abstracts, and full papers was performed by two independent reviewers, followed by data extraction and validity. Study quality and validity were assessed using the Imprecision Tool, Model, and Marker Validity Assessment that has been developed for basic science studies. A total of 403 articles were identified and 31 of those that met the inclusion criteria were selected. 13 different atherogenesis biomarkers in relation to PCSK9 were found, and the most studied biomarkers are LDLR, SREBP, and HNF1α. In terms of quality, our review suggests that the basic science study in investigating atherogenesis biomarkers is deficient in terms of imprecision and validity.

Abstract: Besides the time of exposure to the traditional risk factors, new players take the lead in the modulation of atherogenesis in the very elderly, promoting a step increase in the incidence of cardiovascular events. Accordingly, atherosclerotic plaques become more abundant and portray more unstable features, such as increased inflammatory activity and reduction of smooth muscle cells in the very elderly. This new scenario is composed of new potential modulators of atherogenesis such as cellular senescence, immunosenescence, frailty syndrome, sarcopenia and sirtuins, and changes among the traditional cardiovascular risk factors which gain new attributes and new magnitudes of interaction with atherosclerotic disease. Consistent with this concept, mortality from atherosclerotic disease has shown a decrease in individuals younger than 60 years, but no change in incidence in individuals over the age of 60 years. In this review, we present the most recent and relevant pieces of evidence to the peculiarities of traditional cardiovascular risk factors and new aging-related potential modulators of atherosclerotic disease in very elderly. [Copyright &y& Elsevier]

Abstract: Smoking is a major risk factor for the development of atherosclerosis, stroke and myocardial infarction. Cigarette smoke consists of a complex mixture of about 4000 compounds. Out of these, polycyclic hydrocarbons, tobacco-specific nitrosamines, oxidizing agents and carbon monoxide have been implicated in the development of atherosclerosis. Recent studies have shown that nicotine (the addictive component of cigarettes) binds to high affinity cell–surface receptors and accelerates the atherogenic process. These receptors are called nicotinic acetylcholine receptors (nAChRs) and are expressed ubiquitously in almost all cells existing in the blood vessels. The present review summarizes the pro-atherogenic effects of nAChR ligands such as nicotine and tobacco nitrosamines. The contribution of different nAChR subunits in plaque growth, progression and neovascularization are discussed in detail. The signaling pathways underlying the actions of the nAChRs ligands in blood vessels are also described. Finally, the feasibility of nAChR ligands as therapeutic targets for atherosclerosis is summarized. We believe that the information presented in this review is relevant for atherosclerosis patients who are active smokers, exposed to environmental tobacco smoke or use nicotine patches or gums for smoking cessation. [Copyright &y& Elsevier]

Stromal cell-derived factor-1 (SDF-1) is expressed in a wide variety of organs, such as heart, and plays a pivotal role in the mobilization of hematopoietic stem and progenitor cells in bone marrow. SDF-1α, a common subtype of SDF-1, may control hematopoiesis and angiogenesis, but its role in the pathogenesis of hyperlipidemia is unknown. The aim of this study was to determine the role of SDF-1α in the pathogenesis of hyperlipidemia. First, log-transformed SDF-1α serum levels (logSDF-1α) were significantly higher in male patients with borderline high lipid profile (BHLP; n = 28; 2.15 ± 0.08 ng/ml) compared to control subjects (n = 37; 1.94 ± 0.06 ng/ml; P< 0.01). The logSDF-1α in male patients with high lipid profile (HLP; n = 33; 1.95 ± 0.08 ng/ml) were lower than BHLP patients (P < 0.01). The logSDF-1α was positively associated with HDL-C only in female patients (n = 125; r= 0.379, P = 0.016). These results suggest the different pathophysiology in male and female patients with hyperlipidemia. Moreover, flow cytometry analysis showed that expression of the SDF-1α receptor, CXC-chemokine receptor 4, was lower in peripheral blood mononuclear cells of patients with BHLP (n = 10) and HLP (n = 10), compared to control subjects (n = 10; P < 0.001). Lastly, peripheral blood leukocyte, neutrophil and lymphocyte counts were higher in BHLP patients (n = 62; P < 0.05). Taken together, we suggest SDF-1α as a biomarker of hyperlipidemia that may be helpful to uncover the pathogenesis of hyperlipidemia. [ABSTRACT FROM AUTHOR]

Abstract: The development of cardiovascular pathologies is potentially connected to the surrounding environment, partly due to purely environmental factors, like exposition to pollutions, or anthropological ones, like the type of manual or stressing working activities. The relevant literature has already widely discussed the correlation between the acute and chronic exposition to atmospheric pollutants of different types and the pathogenetic events, such as the atherogenesis, thrombosis, and hypertension, The present study intends to verify this idea on a larger population exposed to different geographical conditions, comparing an agricultural village (Pachino-Siracusa) with an industrialized area (Augusta-Siracusa), both having identical sanitary services of basic importance. On the basis of the specific rates of hospitalizations, we compared the prevalence of cardiovasular pathologies in the resident populations. These studies confirmed the negative influence of the risk factors deriving from the environmental pollutions even on the cardiovascular aging, displaying an increased rate of hospitalization for angina pectoris, myocardial infarction and cardiac arrhytmias in the industrialized population. [Copyright &y& Elsevier]

Plasma levels of high-density lipoprotein (HDL) are strongly and inversely correlated with atherosclerotic cardiovascular diseases. However, it is becoming clear that a functional HDL is a more desirable target than simply increasing HDL-cholesterol levels. The best known antiatherogenic function of HDL particles relates to their ability to promote reverse cholesterol transport from peripheral cells. However, HDL also possesses antioxidant, anti-inflammatory, and antithrombotic effects. This review focuses on the state of knowledge regarding assays of HDL heterogeneity and function and their relationship to cardiovascular diseases. [Copyright &y& Elsevier]

Background--Macrophages play a central role in the development of atherosclerosis. However, the signaling pathways that regulate their function are not well understood. The Rho-associated coiled-coil-containing kinases (ROCK1 and ROCK2) are serine-threonine protein kinases that are involved in the regulation of the actin cytoskeleton. Recent studies suggest that ROCK1 in macrophages and bone marrow-derived cells mediates atherogenesis. However, a similar role for ROCK2 in the pathogenesis of atherosclerosis has not been determined. Methods and Results--The bone marrows from wild-type, ROCK2+/-, and ROCK2-/- mice were transplanted into irradiated recipient low-density lipoprotein receptor-/- mice, and atherosclerosis was induced with a 16-week high-cholesterol diet. Compared with wild-type bone marrow-transplanted mice, ROCK2+/- bone marrow-trans-planted and ROCK2-/- bone marrow-transplanted mice showed substantially less lipid accumulation in the aorta (8.46±1.42% and 9.80±2.34% versus 15.64±1.89%; P<0.01 for both) and decreased atherosclerotic lesions in the subaortic sinus (158.1±44.4 and 330.1 ± 109.5X10³ μm² versus 520.2±125.7X10³ μm²; P<0.01 for both). These findings correlated with decreased foam cell formation (2.27±0.57 versus 4.10±0.3; P<0.01) and increased cholesterol efflux (17.65±0.6 versus 9.75±0.8; P<0.05) in ROCK2-deficient mice that are mediated, in part, through the peroxisome proliferator-activated receptor-y/liver X receptor/ATP-binding cassette transporter A1 pathway in macrophages. Conclusions--ROCK2 contributes to atherosclerosis, in part, by inhibiting peroxisome proliferator-activated receptor-y-mediated reverse cholesterol transport in macrophages, which contributes to foam cell formation. These findings suggest that inhibition of ROCK2 in macrophages may have therapeutic benefits in preventing the development of atherosclerosis. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Systemic inflammatory conditions, as seen in obesity and in the metabolic syndrome, are associated with high plasmatic levels of proatherogenic and prothromboticadipokines and low levels of adiponectin. Inhibitors of HMG-CoA reductase have beneficial effects in reducing cardiovascular events attributed predominantly to its lipid-lowering effects and recent studies suggest that these effects might be due to its anti-inflammatory properties. Based on the pleiotropic properties of simvastatin we studied the effects of this drug on the secretion and expression of adiponectin, PAI-1 and MCP-1 in mature adipocytes under baseline conditions and after an inflammatory stimulation. Materials and methods: The differentiated adipocytes were incubated with 10μM simvastatin or vehicle and TNF-α 10ng/mL or vehicle were added to treatment media. After 24h of incubation, the media was harvested and the proteins of interest were analyzed by Multiplex method. Gene expression was analyzed by real time-PCR. Results: The addition of TNF-α increased the expression and secretion of MCP-1 and PAI-1. However, stimulation did not interfere with the secretion of adiponectin, despite having significantly reduced its expression. Our data also demonstrated that simvastatin reduced the expression and secretion of MCP-1, under baseline (770.4±199.9 vs 312.7±113.7 and 1.00±0.14 vs 0.63±0.13, p <0.05, respectively) and inflammatory conditions (14945±228.7 vs 7837.6±847.4 and 24.16±5.49 vs 14.97±2.67, p <0.05, p <0.05, respectively). Simvastatin also attenuated the increase in expression and secretion of PAI-1 induced by TNF-α (16898.6±1663.3 vs 12922.1±843.9 and 5.19±3.12 vs 0.59±0.16, respectively p <0.05), but under baseline conditions had no effect on the expression or secretion of PAI-1. The statin increased the expression of adiponectin under baseline conditions and inflammatory stimulation (1.03±0.08 vs 4.0±0.96 and 0.77±0.19 vs 2.16±0.23, respectively, p <0.05) and also increased the secretion of this adipokine but only with the inflammatory stimulus (5347.7±1789.3 vs 7327.3±753.6, p <0.05). Conclusions: Our findings suggested that simvastatin counteracted the stimulatory effect of TNF-α on secretion and expression of MCP-1, PAI-1 and adiponectin, implying a potential anti-atherogenic effect during the inflammatory process; these pleitropic effects were more pronounced with HMG-CoA reductase inhibitor. [Copyright &y& Elsevier]

Abstract: Previous studies have reported that C-reactive protein (CRP) interacting with low-density lipoproteins (LDL) affects macrophage activation and LDL uptake. However, the physiological relevance of CRP-LDL interaction with circulating monocytes remains elusive. Moreover, recent studies have shown that CRP exists in two isoforms with partly opposing characteristics pentameric (pCRP) and monomeric CRP (mCRP). Here we investigated the effects of CRP interacting with minimally modified low-density lipoprotein (mmLDL) interaction in regard to events involved in formation of atherosclerotic plaque. We analyzed the effect of mmLDL on human monocytes and found a substantial increase in monocyte activation as evaluated by CD11b/CD18 expression and increased monocyte adhesion under static and under shear flow conditions to human endothelial cells. Monocyte adhesion and activation was attenuated by pCRP via the prevention of mmLDL binding to monocytes. These anti-inflammatory properties of pCRP were lost when it dissociates to the monomeric form. Our results elucidate the physiological relevance of the CRP-mmLDL interaction and furthermore confirm the importance of the previously described pCRP dissociation to mCRP as a localized inflammatory “activation” mechanism. [Copyright &y& Elsevier]

Objectives: To provide evidence that rosuvastatin may improve insulin-resistance and inhibit atherogenesis by modulating insulin signaling, and whether this effect occurs beyond its plasma cholesterol-lowering effect. Methods: Thirty-two 6-week-old low-density lipoprotein receptor deficient mice were randomized into 4 groups ( n = 8 in each group): Normal control group (NC); High fat and high fructose diet group (HFF); HFF plus rosuvastatin group (HFFR); HFFR plus mevalonic acid group (HFFRMA). After 12 weeks, we measured fasting blood sugar, fasting insulin and cholesterol levels; the morphological concentrations of the aorta and aortic sinus; the expression of insulin receptor substrate 2, phosphorylated insulin receptor substrate 2, protein kinase B, phosphorylated protein kinase B and the glucose transporter 4 in the liver. Results: Compared with other groups, fasting blood sugar and fasting insulin increased significantly in HFF group. Furthermore, HFF group had an increase in the morphological concentrations of the aorta and aortic sinus, but there was a significant decrease in the HFFRMA group and the HFFR group. Moreover, there was a high expression of insulin receptor substrate 2, phosphorylated insulin receptor substrate 2, protein kinase B, phosphorylated protein kinase B and the glucose transporter 4 in the HFFRMA and HFFR groups, but a low expression in the HFF group. No significant differences regarding each afore-mentioned index was observed in the HFFR and HFFRMA groups. Conclusions: Our data show that rosuvastatin may improve insulin-resistance and inhibit atherogenesis in HFF-fed mice by partially reversing the decrease in the insulin stimulated insulin receptor substrate 2/Phosphatidylinositol 3-kinase/protein kinase B/glucose transporter 4 pathway in the liver, and that this effect is independent of its cholesterol-lowering effect. [ABSTRACT FROM AUTHOR]

An appreciable amount of evidence generated in the recent decades has changed the incidence and mortality of cardiovascular diseases dramatically. This advance has resulted in increased survival and, consequently, in a large new generation of very elderly individuals. In parallel, the aging of the population brought out a puzzle and a challenge for the next millennium. Despite the role of selective survival in attenuating the expression and impact of traditional risk factors, today's elderly still has a gradual increase in unstable plaque formation and, by this way, the incidence of acute cardiovascular events. Recent studies have indicated aging-related emergence of new potential modulators of atherogenesis such as cellular senescence, immunosenescence, the syndrome of frailty, sarcopenia and sirtuins. This review will focus on the most recent and relevant evidence regarding the impact of these new players on atherogenicity in the elderly. [ABSTRACT FROM AUTHOR]

Abstract: Von Willebrand factor (VWF) is a large multimeric glycoprotein that plays a major role in haemostasis, illustrated by the bleeding tendency in von Willebrand disease (VWD), the most common hereditary bleeding disorder caused by VWF deficiency or dysfunction. Elevated VWF levels are strongly associated with an increased risk of ischemic cardiovascular events. Whether this relation is causal, or whether increased VWF levels reflect disturbances of endothelial function remains to be elucidated. One possibility is that VWF participates in the process of atherogenesis. The aim of the current review is to determine whether VWF deficiency provides protection against the development of atherosclerosis in humans and animals. Results from animal studies suggest that, at arterial branch point predilection sites, VWF deficiency or blockage has a protective effect against atherosclerosis. Based on the available evidence, this potential protective effect of VWF deficiency can most likely be tracked to the VWF–platelet interaction. Sites involved in this interaction could prove attractive targets in future treatment and prevention of cardiovascular disease, an option that is already being explored in humans. An unequivocal protective effect of VWD on atherosclerosis has not been demonstrated in humans. However the interpretation of these results is hampered by several methodological weaknesses. In conclusion, VWF is probably a significant player in the multifaceted interaction between the haemostatic system and the atherosclerotic process which deserves further study. [Copyright &y& Elsevier]

Abstract: In chronic inflammatory diseases, cardiovascular disease risk is increased and is the main cause of increased mortality. Oxidized LDL (oxLDL) and scavenger receptors participate in atherogenesis. Using human arterial endothelial cells (HAECs), we evaluated the effect of IL-6 and TNF-α on the expression of scavenger receptors. IL-6 induced expression of SR-A mRNA and TNF-α induced both SR-A and LOX-1 mRNA. Both did induce either CD36 or CD68. To assess the function of scavenger receptors, MCP-1 production by oxLDL from cytokine-pretreated HAEC was examined. In accordance with scavenger receptor expression, oxLDL-induced MCP-1 production was increased in IL-6- or TNF-α-pretreatment. Serum from rheumatoid arthritis patients but not from healthy subjects increased mRNA expressions of SR-A, LOX-1 and CD36 in HAEC. SR-A expression was inhibited by both anti-IL-6 receptor antibody (α-IL-6R Ab) and TNF-α receptor (p75)-Fc (TNFR-Fc) and LOX-1 expression was inhibited by TNFR-Fc. CD36 expression was affected by neither. Serum from rheumatoid arthritis patients augmented oxLDL-induced MCP-1 production. Both α-IL-6R Ab and TNFR-Fc partially inhibited this MCP-1 production. In conclusion, our results strongly support that blocking therapy of IL-6 and TNF-α might be beneficial to reduce atherosclerosis risk in chronic inflammatory diseases. [Copyright &y& Elsevier]

Medeiros CAM, de Bruin VMS, Andrade GM, Coutinho WM, de Castro-Silva C, de Bruin PFC. Obstructive sleep apnea and biomarkers of inflammation in ischemic stroke. Acta Neurol Scand: 2012: 126: 17-22. © 2011 John Wiley & Sons A/S. Background and Objectives - Despite a confirmed association between obstructive sleep apnea (OSA) and stroke, the pathogenesis of OSA in stroke has not been hitherto clarified. The aim of this study was to evaluate the relationship between respiratory abnormalities and atherogenic pro-inflammatory markers, interleukin-1beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) in acute ischemic stroke patients. Methods - Nocturnal polygraphy was performed in 50 consecutive patients with acute ischemic stroke in the first week after the event. Levels of inflammatory markers (IL-6, IL-1β and TNF-α) were determined from morning blood samples and comparatively analyzed between cases with and without severe OSA and with age-matched controls. Results - All patients with acute ischemic stroke, 31 men, mean age (64.3 ± 7.7 years), had apnea-hypopnea index (AHI) > 5 and 35 (70%) had severe OSA (AHI ≥ 30). Hypertension was more frequent in patients with severe OSA (85.7%) when compared to controls (40.0%) ( P = 0.002). Stroke outcome, assessed by the Barthel index, tended to be more severe ( P = 0.06) in cases with severe OSA. Patients with mild/moderate OSA and with severe OSA showed higher levels of IL-6 when compared to controls ( P = 0.01 and P = 0.000, respectively). Among cases with acute stroke and severe OSA, IL-6 levels were correlated with lower oxyhemoglobin desaturation ( r=−0.30; P = 0.001) and with the desaturation index ( r = 0.15; P = 0.02). Conclusions - IL-6, an atherogenic marker, shows a commensurate increase in stroke patients with OSA. It is correlated with oxyhemoglobin desaturation and with desaturation index and may be a surrogate measure to evaluate continuous positive airway pressure therapy. [ABSTRACT FROM AUTHOR]

Both the aorta and the liver are major organs that play important roles in lipid metabolism, and they are subject to systemic as well as local inflammatory responses in metabolic syndrome. Our previous study indicated that TNFα deficiency influences atherogenesis by reducing inflammation of the aorta. To better understand this phenomenon, the mRNA and protein expression profiles of a panel of cytokines in the aorta and liver of young TNFα-null (TNFα) mice were analyzed and compared with age- and gender-matched wild-type (WT) control mice. In the aorta, IL-2 and GM-CSF were up-regulated versus WT mice, while IL-1β, IL-4, IL-6, IL-10, MCP-1, IFN-γ, and the adhesion molecules ICAM-1 and VCAM-1 were down-regulated. In the liver, however, the expressions of NF-κB, IL-1, IL-2, IL-6, IL-10, ICAM-1, and VCAM-1 were significantly up-regulated in TNFα mice, while IFN-γ and IL-4 were down-regulated. Out of the 62 cytokines analyzed, 22 in the aorta and 27 in the liver were altered by 2-fivefolds at the protein level in TNFα mice. Our data demonstrated that the loss of TNFα function led to various changes in the levels of cytokine expression in these organs at both the transcriptional and translational levels. These results indicated that the changes in cytokine expression patterns in the aorta and the liver may further influence the progression of systemic or local lipid metabolism dysregulation and pathogenesis in animals with TNFα dysfunction representing inflammation-related diseases, such as atherosclerosis and metabolic syndrome. [ABSTRACT FROM AUTHOR]

Background/Aims: L5, the most negatively charged species of low-density lipoprotein (LDL), has been implicated in atherogenesis by inducing apoptosis of endothelial cells (ECs) and inhibiting the differentiation of endothelial progenitor cells. In this study, we compared the effects of LDL charge on cellular stress pathways leading to atherogenesis. Methods: We isolated L5 and L1 (the least negatively charged LDL) from the plasma of patients with familial hypercholesterolemia and used JC-1 staining to examine the effects of L5 and L1 on the mitochondrial membrane potential (DCm) in human umbilical vein ECs (HUVECs). Additionally, we characterized the gene expression profiles of 7 proteins involved in various types of cellular stress. Results: The DCm was severely compromised in HUVECs treated with L5. Furthermore, compared with L1, L5 induced a decrease in mRNA and protein expression of the endoplasmic reticulum (ER) chaperone proteins ORP150, Grp94, and Grp58, mitochondrial proteins Prdx3 and ATP synthase, and an increase in the expression of the pro-inflammatory protein hnRNP C1/C2. Conclusions: Our work suggests that L5, but not L1, may promote the destruction of ECs that occurs during atherogenesis by causing mitochondrial dysfunction and modulating the expression of key proteins to promote inflammation, ER dysfunction, oxidative stress, and apoptosis. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Myeloperoxidase (MPO), a member of the heme peroxidase superfamily, is a leukocyte-derived enzyme that generates reactive intermediates, leading to oxidative damage of host lipids and proteins. It has been shown that MPO is present within atherosclerotic plaque in human arteries and contributes to atherogenesis by catalyzing oxidative reactions in the vascular wall. This review provides an overview of the analytical and pathophysiologic characteristics of MPO and summarizes the possible clinical applicability of MPO as a marker for diagnosis of acute coronary syndrome and a marker for prediction of cardiovascular disease. [ABSTRACT FROM AUTHOR]

Abstract: Atherogenesis refers to the development of atheromatous plaques in the inner lining of the arteries. These atherosclerotic lesions are characterized by accumulation of monocyte-derived macrophage-foam cells loaded with cholesterol, which eventually undergo apoptotic death, leading finally to formation of the necrotic core of the plaque. Atheroma formation also involves the recruitment of smooth muscle cells (SMC) from the media into the intima, where they proliferate and form the neointima in a process called “remodeling”. Cells in the advanced atherosclerotic plaques express high levels of the serine protease urokinase-type plasminogen activator (uPA) and its receptor (uPAR). uPA is a multi-functional multi-domain protein that is not only a regulator of fibrinolysis, but it is also associated with several acute and chronic pathologic conditions. uPA mediate the extracellular matrix (ECM) degradation, and plays a pivotal role in cell adhesion, migration and proliferation, during tissue remodeling. On cell surface uPA binds to the high affinity urokinase receptor, providing a strictly localized proteolysis of ECM proteins. The uPA/uPAR complex also activates intracellular signaling, thus regulating cellular function. An imbalance in the uPA/uPAR system leads to dis-orders in tissue structure and function. This review summarizes recent progress in understanding the role and mechanisms of the uPA/uPAR system in atherogenesis. [Copyright &y& Elsevier]

Abstract: Objective: As ABCG1 plays a role in cholesterol efflux, macrophage ABCG1 expression has been suggested to protect against atherosclerosis. However, we and others observed varying effects of ABCG1 deficiency on atherosclerotic lesion size. The objective of this study was to define the effect of ABCG1 deficiency during atherosclerotic lesion progression in LDL receptor knockout (LDLr−/−) mice. Methods and results: ABCG1−/−/LDLr−/− and ABCG1+/+/LDLr−/− littermates were fed a Western-type diet for 10 and 12 weeks in order to study the effect of ABCG1 deficiency in the exponential phase of atherosclerotic lesion formation. At 10 weeks of diet feeding, a significant 1.5-fold increase in early atherosclerotic lesion size (130±12×103 μm2) was observed in ABCG1−/−/LDLr−/− mice compared to ABCG1+/+/LDLr−/− mice (88±11×103 μm2; p <0.05). Interestingly, in more advanced lesions, induced by 12 weeks of WTD feeding, ABCG1−/−/LDLr−/− mice showed a significant 1.7-fold decrease in atherosclerotic lesion size (160±20×103 μm2 vs 273±19×103 μm2 in control mice; p <0.01), indicating that in the ABCG1−/−/LDLr−/− mice progression of lesion formation is retarded as compared to ABCG1+/+/LDLr−/− mice. In addition, correlation analysis performed on 7 independent published studies and the current study confirmed that ABCG1 is atheroprotective in early lesions, while the development of advanced lesions is stimulated. Conclusions: It appears that the effect of ABCG1 deficiency on lesion development in LDLr−/− mice depends on the stage of atherogenesis, whereby the absence of ABCG1 leads to increased lesions at sizes<167×103 μm2 while in more advanced stages of atherosclerosis enhanced apoptosis and/or compensatory mechanisms lead to retarded lesion progression. [Copyright &y& Elsevier]

The article presents information on the association between atherosclerosis and sudden cardiac arrest (SCA). It is discussed that coronary heart disease (CHD) is characterized by several substrate patterns which may interact with triggers to initiate multiple patterns of expression and SCA a challenging mode of expression as it is unpredictable and is susceptible to being triggered by several modulators. Progress in management of the disease will require cumulative-effects model.

Plasma cholesterol levels have been strongly associated with atherogenesis, underscoring the role of lipid metabolism in defining cardiovascular disease risk. However, the atherosclerotic plaque is highly dynamic and contains elements of both the innate and adaptive immune system that respond to the aberrant accumulation of lipids in the subendothelial space. Previous research has focused on defining how proinflammatory cytokines synthesized by macrophages, such as interleukin-1β (IL-1β), modulate the progression of atherosclerosis, supporting the notion that chronic inflammation accelerates atherogenesis. More recently, emphasis has been placed on the elucidation of the mechanisms that contribute to pro-IL-1β production and finally its processing via multiprotein complexes termed the inflammasomes, a family of cytosolic multiprotein complexes that serve as sensors of either pathogen invasion or cellular stress (ie, cholesterol crystals) and work via triggering caspase-1-mediated processing of pro-IL-1β to IL-1β. Based on this link between cholesterol metabolism, NLRP3 inflammasome activation, and IL-1β release, it is important to re-evaluate how the atherogenic environment stimulates immune cells to produce IL-1β. [ABSTRACT FROM AUTHOR]

Atherosclerosis together with its cardiovascular consequences is the most common and significant cause of death, particularly in highly developed countries. The process of atherogenesis begins as soon as in childhood and depends on classical risk factors. Atherosclerosis also results from a chronic inflammatory-immune process which takes place in the vascular walls. Furthermore, it has been known for a number of years that the development of atherosclerotic lesions is closely connected with the concentration of homocysteine in serum. Homocysteine is a sulfur amino acid originating from methionine. An increased concentration of homocysteine in blood harmfully influences blood vessels, leading to a higher risk of ischemic heart disease and stroke. Since tackling classical atherosclerosis risk factors is not efficient enough when it comes to protecting the cardiovascular system from diseases, new substances possessing anti-atherogenic properties, especially endogenous ones, are sought. Recently, researchers have paid attention to a connection between homocysteine and an endogenous tryptophan derivative, kynurenic acid. Recently, it was revealed that kynurenic acid counteracts the harmful effects of homocysteine on endothelium cells in vitro. The hypothesis assuming homocysteine-kynurenate interplay suggests the existence of a new mechanism of atherogenesis and gives us an opportunity to use this knowledge in both prevention and treatment of cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Background: Exercise training (ET) in addition to optimal medical therapy (OMT) in patients with stable coronary artery disease (CAD) has been demonstrated to be superior to percutaneous coronary interventions (PCI) with respect to the composite endpoint of death, myocardial infarction, stroke, revascularization and hospitalization due to worsening of angina. One mechanism leading to this superiority discussed in the literature is the increase in coronary collateral blood flow due to ET. Until now, data demonstrating the positive effect of ET on the collateral blood flow and the functional capacity of the coronary collateral circulation are still lacking. Methods/design: The EXCITE trial is a three-armed randomized, prospective, single-center, open-label, controlled study enrolling 60 patients with stable CAD and at least one significant coronary stenosis (fractional flow reserve ≤0.75). The study is designed to compare the influence and efficacy of two different 4-week ET programs [high intensityinterval trainings (IT) versus moderate-intensity exercise training (MT) in addition to OMT] versus OMT only on collateral blood flow (CBF). The primary efficacy endpoint is the change of the CBF of the target vessel after 4 weeks as assessed by coronary catheterization with a pressure wire during interruption of the antegrade flow of the target vessel by balloon occlusion. Secondary endpoints include the change in plaque composition as assessed by intravascular ultrasound (IVUS) after 4 weeks, myocardial perfusion as analyzed in MRI after 4 weeks and 12 months, peak oxygen uptake (V02 peak), change in endothelial function and biomarkers after 4 weeks, 3, 6 and 12 months. The safety endpoint addresses major adverse cardiovascular events (death from cardiovascular cause, myocardial infarction, stroke, TIA, target vessel revascularization or hospitalization) after 12 months. Discussion: The trial investigates whether ET for 4 weeks increases the CBF in patients with significant CAD compared to a sedentary control group. It also examines the impact of two intensities of ET on the CBF as well as the histological plaque composition. The trial started recruitment in June 2009 and will complete recruitment until June 2012. First results are expected in December 2012 (4-week follow-up), final results (12-month long-term secondary endpoint) in December 2013. [ABSTRACT FROM AUTHOR]

Background: Persistent vascular inflammation has been implicated as an important cause for a higher prevalence of cardiovascular disease (CVD) in HIV-infected adults. In several populations at high risk for CVD, vascular 18Fluorodeoxyglucose (18FDG) uptake quantified using 3D-positron emission-computed tomography (PET-CT) has been used as a molecular level biomarker for the presence of metabolically active proinflammatory macrophages in rupture-prone early atherosclerotic plaques. We hypothesized that 18FDG PET-CT imaging would detect arterial inflammation and early atherosclerosis in HIV-infected adults with modest CVD risk. Methods: We studied 9 HIV-infected participants with fully suppressed HIV viremia on antiretroviral therapy (8 men, median age 52 yrs, median BMI 29 kg/m 2, median CD4 count 655 cells/µL, 33% current smokers) and 5 HIV-negative participants (4 men, median age 44 yrs, median BMI 25 kg/m2, no current smokers). Mean Framingham Risk Scores were higher for HIV-infected persons (9% vs. 2%, p<0.01). 18FDG (370 MBq) was administered intravenously. 3D-PET-CT images were obtained 3.5 hrs later. 18FDG uptake into both carotid arteries and the aorta was compared between the two groups. Results: Right and left carotid 18FDG uptake was greater (P<0.03) in the HIV group (1.77 ±0.26, 1.33 ±0.09 target to background ratio (TBR)) than the control group (1.05 ± 0.10, 1.03 ± 0.05 TBR). 18FDG uptake in the aorta was greater in HIV (1.50 ±0.16 TBR) vs control group (1.24 ± 0.05 TBR), but did not reach statistical significance (P = 0.18). Conclusions: Carotid artery 18FDG PET-CT imaging detected differences in vascular inflammation and early atherosclerosis between HIV-infected adults with CVD risk factors and healthy HIV-seronegative controls. These findings confirm the utility of this molecular level imaging approach for detecting and quantifying glucose uptake into inflammatory macrophages present in metabolically active, rupture-prone atherosclerotic plaques in HIV infected adults; a population with increased CVD risk. [ABSTRACT FROM AUTHOR]

Abstract: Aims: The oxidized low-density lipoprotein receptor LOX-1 is up-regulated on activated endothelial cells, for example, the endothelium of atherosclerosis-prone sites, in both human and animal models. We examined whether endothelial LOX-1 overexpression may contribute to atherogenesis. Methods: Adenoviral vectors expressing LOX-1 or LOXIN (a splice variant of LOX-1 with inhibitory function) were created and used to transduce the normally lesion-free common carotid artery, in high fat-fed female ApoE−/− mice. Mice were placed on high-fat diet for 4 weeks prior to gene transfer with either LOX-1 or a combination of LOX-1 and LOXIN, and assessment of plaque development analyzed 6 weeks following gene transfer. Results: Compared to controls, LOX-1 transduction induced a significant increase in plaque coverage within the common carotid artery to 91% compared to 50% after RAd66 control virus infection (P≤.05). This was inhibited by co-expression of LOXIN (62%). Conclusions: These results demonstrate that up-regulation of LOX-1 promotes atherogenesis, highlighting LOX-1 function as a target for intervention. In addition, this study further demonstrated the inhibitory function of LOXIN. [Copyright &y& Elsevier]

Abstract: Inflammation and stress are regarded as two important atherogenic factors. Because stress can affect leukocyte distribution, we hypothesized that stress-mediated leukocyte extravasation can modify the inflammatory environment of the arterial wall possibly contributing to atherogenesis. To test this hypothesis we evaluated the inflammatory environment of the aorta in C57Bl/6 mice subjected to 3 and 12months of chronic stress and compared it to age matched non-stressed animals. Experiments were carried out in mice fed regular chow or atherogenic diets. Both treatments increased the expression of vascular and leukocyte adhesion molecules and leukocyte accumulation. At 3months, stress but not an atherogenic diet elevated the number of CD4 cells, CD8 cells, macrophages, dendritic cells and neutrophils. These changes were associated with elevation of transcripts for ICAM-1 and VCAM-1, E-selectin and neuropeptide Y. At 12months, stress or high cholesterol acted similarly to elevate the number of CD8 and macrophages, and synergistically on the number of all cell types investigated. At this time-point, strong synergism was also observed on the level of E-selectin and NPY in the aorta, but not in the circulation. Despite these effects, histological and morphological alterations of the arterial wall were severe in the atherogenic diet, but not in the stress groups. Thus, although stress and an atherogenic diet may both affect leukocyte accumulation in the aorta, they may contribute differently to atherogenesis. [Copyright &y& Elsevier]

Abstract: Ethnopharmacological significance: Panax notoginseng saponins (PNS) are ingredients extracted from traditional Chinese medicinal herb Panax notoginseng. It has been demonstrated that PNS have extensive effects on the cardiovascular system, including inhibition of platelet aggregation, increasing blood flow, improving left ventricular diastolic function in hypertensive patients and anti-inflammatory effect. Aim of study: Recent researches indicated that PNS administration inhibited foam cells’ formation. The present study was designed to study the effects of PNS on atherogenesis and to explore the relevant molecular mechanisms. Materials and methods: The Zymosan A induced atherosclerosis models were used to investigate the anti-atherosclerosis effects of PNS. The integrin express array was used to check the changes of integrins. The foam cell formation was observed with transmission electron microscope. The effect of PNS on phosphorylation of FAK on threonine 397 and protein level of NF-κB was also evaluated in vitro. Results: PNS treated rats had less plaque spots on the aortas compared with Zym induced group. The formation of foam cell was inhibited by PNS. Compared with Zym treated group, the expression of most integrin families decreased except Itgav and Itgb2 after PNS treatment. PNS inhibited phosphorylation of FAK on threonine 397 and translocation of NF-κB. Conclusion: High fat diet together with Zym induces atherogenesis of rat. PNS inhibits zymosan A induced atherogenesis by suppressing FAK phosphorylation, integrins expression and NF-κB translocation. [Copyright &y& Elsevier]

Contents of mRNAs encoding endosome/lysosome components EEA1, Rab5a, Lamp1, Lamp2, p62 (SQSTM1), and CD63 were measured by quantitative PCR and compared in intact fragments of human aorta and in aorta fragments with atherosclerotic lesions of stage II (fatty streaks) of the same donors. During atherogenesis an increase was detected only in the level of p62 mRNA but not in other mRNAs. Nevertheless, correlation analysis revealed a profound rearrangement of inter-gene correlations: only 30% of correlations found in the fatty streaks coincided with the correlations in normal fragments. Thus, new constellations were formed in fatty streaks concurrently with disappearance of correlations between mRNAs under study and mRNAs encoding factors of lipid accumulation, reverse cholesterol transfer, and some lipid sensors/transcription regulators of lipid metabolism. [ABSTRACT FROM AUTHOR]