Inflammation meets oxidation: NF-kappaB as a mediator of initial lesion development in atherosclerosis

Helicobacter pylori components increase the severity of metabolic syndrome and its hepatic manifestations induced by a high fat diet

The metabolic syndrome, often accompanied by hepatic manifestations, is a high-risk factor for developing cardiovascular disease. Patients with metabolic dysfunction associated with steatohepatic disease (MASDL) are at significant risk of developing coronary artery disease. Atherosclerosis is a systemic inflammatory disorder in which several factors, including dietary or infectious factors, can cause an inflammatory response. Helicobacter pylori (HP) bacteria have been implicated in the progression of proatherogenic vascular endothelial lesions, moreover, our previous study in an experimental in vivo model of Cavia porcellus showed that HP components and high-fat substances acted synergistically in promoting vascular endothelial inflammation, leading to an early onset of a proatherogenic environment. In the present study, our goal was to determine the contribution of HP components to the development of hepatic manifestations of metabolic syndrome in an experimental model. Our results showed that HP infection in animals exposed to a high-fat diet increased oxidative stress and lipid peroxidation, followed by endothelial lipid deposition, impaired endothelial apoptosis, cell lysis, and increased vascular stiffness. Finally, histopathological analysis of liver tissue showed signs of MASLD development in HP-infected animals fed a high-fat diet.

The role of peroxisome proliferator-activated receptor γ in lipid metabolism and inflammation in atherosclerosis

Cardiovascular disease events are the result of functional and structural abnormalities in the arteries and heart. Atherosclerosis is the main cause and pathological basis of cardiovascular diseases. Atherosclerosis is a multifactorial disease associated with dyslipidemia, inflammation, and oxidative stress, among which dyslipidemia and chronic inflammation occur in all processes. Under the influence of lipoproteins, the arterial intima causes inflammation, necrosis, fibrosis, and calcification, leading to plaque formation in specific parts of the artery, which further develops into plaque rupture and secondary thrombosis. Foam cell formation from macrophages is an early event in the development of atherosclerosis. Lipid uptake causes a vascular inflammatory response, and persistent inflammatory infiltration in the lesion area further promotes the development of the disease. Inhibition of macrophage differentiation into foam cell and reduction of the level of proinflammatory factors in macrophages can effectively alleviate the occurrence and development of atherosclerosis. Peroxisome proliferator-activated receptor γ (PPARγ) is a ligand-activated nuclear receptor that plays an important antiatherosclerotic role by regulating triglyceride metabolism, lipid uptake, cholesterol efflux, macrophage polarity, and inhibiting inflammatory signaling pathways. In addition, PPARγ shifts its binding to ligands and co-activators or co-repressors of transcription of target genes through posttranslational modification, thereby affecting the regulation of its downstream target genes. Many ligand agonists have also been developed targeting PPARγ. In this review, we summarized the role of PPARγ in lipid metabolism and inflammation in development of atherosclerosis, the posttranslational regulatory mechanism of PPARγ, and further discusses the value of PPARγ as an antiatherosclerosis target.

The Pharmacological Efficacy of Baicalin in Inflammatory Diseases

Baicalin is one of the most abundant flavonoids found in the dried roots of Scutellaria baicalensis Georgi (SBG) belonging to the genus Scutellaria. While baicalin is demonstrated to have anti-inflammatory, antiviral, antitumor, antibacterial, anticonvulsant, antioxidant, hepatoprotective, and neuroprotective effects, its low hydrophilicity and lipophilicity limit the bioavailability and pharmacological functions. Therefore, an in-depth study of baicalin's bioavailability and pharmacokinetics contributes to laying the theoretical foundation for applied research in disease treatment. In this view, the physicochemical properties and anti-inflammatory activity of baicalin are summarized in terms of bioavailability, drug interaction, and inflammatory conditions.

An update on the role of TRIM/NLRP3 signaling pathway in atherosclerosis

Atherosclerosis (AS) is a chronic inflammatory disease of large and medium arteries that includes lipid metabolism disorder and recruitment of immune cells to the artery wall. An increasing number of studies have confirmed that inflammasome over-activation is associated with the onset and progression of atherosclerosis. The NLRP3 inflammasome, in particular, has been proven to increase the incidence rate of cardiovascular diseases (CVD) by promoting pro-inflammatory cytokine release and reducing plaque stability. The strict control of inflammasome and prevention of excessive inflammatory reactions have been the research focus of inflammatory diseases. Tripartite motif (TRIM) is a protein family with a conservative structure and rapid evolution. Several studies have demonstrated the TRIM family's regulatory role in mediating inflammation. This review aims to clarify the relationship between TRIMs and NLRP3 inflammasome and provide insights for future research and treatment discovery.

The role of autophagy in cardiovascular disease: Cross-interference of signaling pathways and underlying therapeutic targets

Autophagy is a conserved lysosomal pathway for the degradation of cytoplasmic proteins and organelles, which realizes the metabolic needs of cells and the renewal of organelles. Autophagy-related genes (ATGs) are the main molecular mechanisms controlling autophagy, and their functions can coordinate the whole autophagic process. Autophagy can also play a role in cardiovascular disease through several key signaling pathways, including PI3K/Akt/mTOR, IGF/EGF, AMPK/mTOR, MAPKs, p53, Nrf2/p62, Wnt/β-catenin and NF-κB pathways. In this paper, we reviewed the signaling pathway of cross-interference between autophagy and cardiovascular diseases, and analyzed the development status of novel cardiovascular disease treatment by targeting the core molecular mechanism of autophagy as well as the critical signaling pathway. Induction or inhibition of autophagy through molecular mechanisms and signaling pathways can provide therapeutic benefits for patients. Meanwhile, we hope to provide a unique insight into cardiovascular treatment strategies by understanding the molecular mechanism and signaling pathway of crosstalk between autophagy and cardiovascular diseases.

Extracellular Vesicles and Vascular Inflammation

Vascular inflammation is the most common pathological feature in the pathogenesis of human disease. It is a complex immune process involved with many different types of cells including platelet, monocytes, macrophages, endothelial cells, and others. It is widely accepted that both innate and adaptive immune responses are important for the initiation and progression of vascular inflammation. The cell-cell interaction constitutes an important aspect of those immune responses in the vascular inflammation. Extracellular vesicles (EVs) are nanometer-sized double-layer lipid membrane vesicles released from most types of cells. They have been proved to play critical roles in intercellular communication in the occurrence and development of multisystem diseases. With the advancement of basal medical science, the biological roles of EVs in vascular inflammation have been clearer today. In this chapter, we will summarize the advance progress of extracellular vesicles in regulating vascular inflammation and its potential application in the clinical.

Costunolide alleviates atherosclerosis in high-fat diet-fed ApoE-/- mice through covalently binding to IKKβ and inhibiting NF-κB-mediated inflammation

Costunolide (CTD) is a sesquiterpene lactone isolated from costus root and exhibits various biological activities including anti-inflammation. Since atherosclerosis is a chronic inflammatory disease, we herein investigated the anti-atherosclerotic effects of CTD and the underlying mechanism. Atherosclerosis was induced in ApoE-/- mice by feeding them with a high-fat diet (HFD) for 8 weeks, followed by administration of CTD (10, 20 mg ·kg-1·d-1, i.g.) for 8 weeks. We showed that CTD administration dose-dependently alleviated atherosclerosis in HFD-fed ApoE-/- mice. Furthermore, we found that CTD dose-dependently reduced inflammatory responses in aortas of the mice, as CTD prevented infiltration of inflammatory cells in aortas and attenuated oxLDL uptake in macrophages, leading to reduced expression of pro-inflammatory and pro-fibrotic molecules in aortas. Similar results were observed in oxLDL-stimulated mouse primary peritoneal macrophages (MPMs) in vitro. We showed that pretreatment with CTD (2.5, 5. 10 μM) restrained oxLDL-induced inflammatory responses in MPMs by blocking pro-inflammatory NF-κB/p65 signaling pathway. We further demonstrated that CTD inactivated NF-κB via covalent binding to cysteine 179 on IKKβ, a canonical upstream regulator of NF-κB, reducing its phosphorylation and leading to conformational change in the active loop of IKKβ. Our results discover IKKβ as the target of CTD for its anti-inflammatory activity and elucidate a molecular mechanism underlying the anti-atherosclerosis effect of CTD. CTD is a potentially therapeutic candidate for retarding inflammatory atherosclerotic diseases.

Searching for serum biomarkers linking coronary heart disease and Helicobacter pylori infection using infrared spectroscopy and artificial neural networks

Helicobacter pylori (Hp) Gram-negative bacteria cause gastritis or gastric ulcers. They may be involved in the development of systemic diseases i.e. coronary heart disease (CHD). Both Hp infection and CHD are related to inflammation accompanied by C-reactive protein (CRP), tumor necrosis factor alfa (TNF-α) and homocysteine. Low density lipoprotein (LDL) and triglicerides are a classic risk factors of CHD. Infrared spectroscopy has been introduced for monitoring chronic infections or endogenous disorders using specific absorption bands for biocomponents typed as diagnostic markers. In this study we selected specific motives of infrared radiation (IR) spectra for the sera from CHD patients infected with Hp. In total 141 sera were used: 90 from patients with CHD, all Hp positive, and 51 from healthy donors, 32 Hp negative and 21 Hp positive. Hp status was evaluated by anti-Hp IgG antibodies and/or ¹³C urea breath testing. IR spectra were measured using FT-IR/FT-NIR Spectrum 400 spectrometer (PerkinElmer) chemometrically analyzed using artificial neural networks and they showed differences in absorption bands corresponding to triglicerides, CRP, homocysteine, LDL and TNF-α, and selected component groups between CHD patients infected with Hp vs healthy uninfected donors (96.15% accuracy). Triglicerides and CRP were the best biomarkers linking Hp infection with CHD.

Longevity-Promoting Pathways and Transcription Factors Respond to and Control Extracellular Matrix Dynamics During Aging and Disease

Aging is one of the largest risk factors for cancer, type 2 diabetes, osteoarthritis, cardiovascular diseases, and other age-related pathologies. Here, we give a detailed description of the interplay of chronic age-related pathologies with the remodeling of the extracellular matrix during disease development and progression. Longevity-promoting signaling pathways slow or prevent age-related diseases. In particular, we focus on the mTOR signaling pathway, sirtuins, and canonical longevity-promoting transcription factors, such as FOXO, NF-κB, and Nrf2. We extend our analysis using chromatin immunoprecipitation (ChIP) sequencing and transcriptomic data and report that many established and emerging longevity-promoting transcription factors, such as CREB1, FOXO1,3, GATA1,2,3,4, HIF1A, JUN, KLF4, MYC, NFE2L2/Nrf2, RELA/NF-κB, REST, STAT3,5A, and TP53/p53, directly regulate many extracellular matrix genes and remodelers. We propose that modulation of these pathways increases lifespan and protects from age-related diseases in part due to their effects on extracellular matrix remodeling. Therefore, to successfully treat age-related diseases, it is necessary to better understand the connection between extracellular matrix components and longevity pathways.

Accumulation of Deleterious Effects in Gastric Epithelial Cells and Vascular Endothelial Cells In Vitro in the Milieu of Helicobacter pylori Components, 7-Ketocholesterol and Acetylsalicylic Acid

The Gastric pathogen Helicobacter pylori (HP) may influence the development of coronary heart disease (CHD). H. pylori induce reactive oxygen species (ROS), which transform cholesterol to 7-ketocholesterol (7-kCh), a CHD risk factor. Acetylsalicylic acid (ASA)—an Anti-aggregation drug used in CHD patients—may increase gastric bleeding and inflammation. We examined whether H. pylori driven ROS effects in the cell cultures of gastric epithelial cells (AGS) and vascular endothelial cells (HUVEC) progress in the milieu of 7-kCh and ASA. Cell cultures, exposed to 7-kCh or ASA alone or pulsed with the H. pylori antigenic complex—Glycine acid extract (GE), urease (UreA), cytotoxin associated gene A (CagA) protein or lipopolysaccharide (LPS), alone or with 7-kCh and ASA—were examined for ROS, apoptosis, cell integrity, interleukin (IL)-8, the activation of signal transducer, the activator of transcription 3 (STAT3), and wound healing. ASA and 7-kCh alone, and particularly in conjunction with H. pylori components, increased the ROS level and the rate of apoptosis, which was followed by cell disintegration, the activation of STAT3, and IL-8 elevation. AGS cells were unable to undergo wound healing. The cell ROS response to H. pylori components may be elevated by 7-kCh and ASA.

Antibodies towards TVLLPVIFF Amino Acid Sequence of TNF Receptor Induced by Helicobacter pylori in Patients with Coronary Heart Disease

Background: Molecular mimicry between Helicobacter pylori (Hp) and the host components resulting in induction of cross-reacting antibodies has been suggested as accessory mechanism in the development of coronary heart disease (CHD). A potential target for antibodies induced during Hp infection by the components of these bacteria might be amino acid sequence TVLLPVIFF (P1) of tumor necrosis factor receptor (TNFR), which is exposed on vascular endothelium and immunocompetent cells, driving inflammation. Aim: To examine whether anti-P1 IgG are induced during Hp infection in CHD patients. Methods: Sera from CHD patients infected with Hp (54) vs. sera of uninfected healthy donors (22) were tested by the ELISA for anti-H. pylori antibodies, anti-P1 IgG, and for antibodies towards control sequence IAKEGFEKIS (P2). Sera of Caviae porcellus infected experimentally with Hp (30) or uninfected (10) were included into this study. The same serum samples, which were positive for anti-P1 IgG, were adsorbed with Hp and then subjected to the ELISA. The biological activity of anti-P1 IgG was assessed in complement (C1q) binding assay. Results: Sera of 43 CHD patients seropositive for anti-Hp IgG contained anti-P1 IgG binding C1q. Additionally, 10 serum samples of animals seropositive for anti-Hp IgG contained anti-P1 IgG. Anti-P1 IgG in tested sera were neutralized by their adsorption with Hp. Conclusion: In CHD patients infected with Hp, antibodies cross-reacting with TNFR common sequence are produced. Further studies are necessary to define immunogenic Hp determinants and to confirm possible cellular effects of cross-reacting antibodies.

Baicalin Alleviates Thrombin-Induced Inflammation in Vascular Smooth Muscle Cells

Atherosclerosis (AS) is a chronic inflammatory disease of the arterial intima. As AS represents the most common type of vascular disease, it affects millions of individuals and is a source of high morbidity and mortality rates worldwide. Overwhelming evidence indicates that AS-related inflammation is mediated by proinflammatory cytokines, chemokines, adhesion molecules and inflammatory signaling pathways, with each of these factors being shown to play critical roles during the entire progression of AS. While a number of drugs have been approved for use in the treatment of AS, their benefits are modest, which underscores the urgency for the development of new drug therapies. In part, these deficits in effective drugs can be attributable to the lack of a clear understanding of the molecular mechanisms of AS. In this study, we investigate the capacity for thrombin to trigger inflammation and induce cell proliferation in vascular smooth muscle cells (VSMCs). We then assessed the effects of baicalin and its potential mechanisms on VSMC inflammation as induced by thrombin. Baicalin, which is a natural bioactive compound of S. baicalensis Georgi (SBG), exerted a protective effect against thrombin-induced VSMC inflammation as resulting from the upregulation of PAR-1. This protection as exerted by baicalin appears to reside in its capacity to produce an inhibitory effect on the thrombin-induced activation of the ERK1/2 pathway. These findings suggest that baicalin may be a promising candidate for the treatment of atherosclerosis.

Reactive-oxygen-species-scavenging nanomaterials for resolving inflammation

Reactive oxygen species (ROS) mediate multiple physiological functions; however, the over-accumulation of ROS causes premature aging and/or death and is associated with various inflammatory conditions. Nevertheless, there are limited clinical treatment options that are currently available. The good news is that owing to the considerable advances in nanoscience, multiple types of nanomaterials with unique ROS-scavenging abilities that influence the temporospatial dynamic behaviors of ROS in biological systems have been developed. This has led to the emergence of next-generation nanomaterial-controlled strategies aimed at ameliorating ROS-related inflammatory conditions. Accordingly, herein we reviewed recent progress in research on nanotherapy based on ROS scavenging. The underlying mechanisms of the employed nanomaterials are emphasized. Furthermore, important issues in developing cross-disciplinary nanomedicine-based strategies for ROS-based inflammatory conditions are discussed. Our review of this increasing interdisciplinary field will benefit ongoing studies and clinical applications of nanomedicine based on ROS scavenging.

Helicobacter pylori Infection Acts Synergistically with a High-Fat Diet in the Development of a Proinflammatory and Potentially Proatherogenic Endothelial Cell Environment in an Experimental Model

Classic atherosclerosis risk factors do not explain all cases of chronic heart disease. There is significant evidence that gut microbiota may influence the development of atherosclerosis. The widespread prevalence of chronic Helicobacter pylori (H. pylori, HP) infections suggests that HP can be the source of components that stimulate local and systemic inflammatory responses. Elevated production of reactive oxygen species during HP infection leads to cholesterol oxidation, which drives atherogenesis. The aim of this study is to explore the link between persistent HP infection and a high-fat diet in the development of proinflammatory conditions that are potentially proatherogenic. An in vivo model of Caviae porcellus infected with HP and exposed to an experimental diet was investigated for the occurrence of a proinflammatory and proatherogenic endothelial environment. Vascular endothelial primary cells exposed to HP components were tested in vitro for oxidative stress, cell activation and apoptosis. The infiltration of inflammatory cells into the vascular endothelium of animals infected with HP and exposed to a high-fat diet was observed in conjunction with an increased level of inflammatory markers systemically. The arteries of such animals were the least elastic, suggesting the role of HP in arterial stiffness. Soluble HP components induced transformation of macrophages to foam cells in vitro and influenced the endothelial life span, which was correlated with Collagen I upregulation. These preliminary results support the hypothesis that HP antigens act synergistically with a high-fat diet in the development of proatherogenic conditions.

Profilin 1 and Mitochondria-Partners in the Pathogenesis of Coronary Artery Disease?

Atherosclerosis remains a large health and economic burden. Even though it has been studied for more than a century, its complex pathophysiology has not been elucidated. The relatively well-established contributors include: chronic inflammation in response to oxidized cholesterol, reactive oxygen species-induced damage and apoptosis. Recently, profilin 1, a regulator of actin dynamics emerged as a potential new player in the field. Profilin is abundant in stable atherosclerotic plaques and in thrombi extracted from infarct-related arteries in patients with acute myocardial infarction. The exact role of profilin in atherosclerosis and its complications, as well as its mechanisms of action, remain unknown. Here, we summarize several pathways in which profilin may act through mitochondria in a number of processes implicated in atherosclerosis.

Regulatory Mechanisms of Baicalin in Cardiovascular Diseases: A Review

Cardiovascular diseases (CVDs) is the leading cause of high morbidity and mortality worldwide, which emphasizes the urgent necessity to develop new pharmacotherapies. In eastern countries, traditional Chinese medicine Scutellaria baicalensis Georgi has been used clinically for thousands of years. Baicalin is one of the main active ingredients extracted from Chinese herbal medicine S. baicalensis. Emerging evidence has established that baicalin improves chronic inflammation, immune imbalance, disturbances in lipid metabolism, apoptosis and oxidative stress. Thereby it offers beneficial roles against the initiation and progression of CVDs such as atherosclerosis, hypertension, myocardial infarction and reperfusion, and heart failure. In this review, we summarize the pharmacological features and relevant mechanisms by which baicalin regulates CVDs in the hope to reveal its application for CVDs prevention and/or therapy.

Celastrol attenuates arterial and valvular calcification via inhibiting BMP2/Smad1/5 signalling

Vascular calcification is an important risk factor for the mortality and morbidity in chronic kidney disease (CKD). Unfortunately, until now there is no certain medication targeting vascular calcification in CKD. In this study, we explored the inhibitory effect of celastrol on high calcium–induced vascular calcification and the underlying molecular mechanisms. Cell proliferation assay showed that celastrol inhibited aortic valve interstitial cell (VIC) and vascular smooth muscle cell (VSMC) proliferation when its concentration was higher than 0.6 μmol/L. 0.8 μmol/L celastrol inhibited the expression of osteogenic genes and calcium deposition induced by high‐calcium medium in both AVICs and VSMCs. In mouse vascular calcification model induced by adenine combined with vitamin D, alizarin red and immunostaining showed that celastrol inhibited pro‐calcification gene expression and calcium deposition in aortic wall and aortic valve tissues. At the molecular level, celastrol inhibited the increase of BMP2, phosphorylated Smad1/5 (p‐Smad1/5) and non‐phosphorylated β‐catenin (n‐p‐β‐catenin) induced by high‐calcium medium both in vitro and in vivo. Also, BMP2 overexpression reversed the anti‐calcification effects of celastrol by recovering the decrease of p‐Smad1/5 and n‐p‐β‐catenin. Furthermore, celastrol prevented the up‐regulation of BMPRII and down‐regulation of Smad6 induced by high calcium, and this protectory effect can be abolished by BMP2 overexpression. In conclusion, our data for the first time demonstrate that celastrol attenuates high calcium–induced arterial and valvular calcification by inhibiting BMP2/Smad1/5 signalling, which may provide a novel therapeutic strategy for arterial and valvular calcification in patients with CKD.

Wnt5a/Ror2 pathway contributes to the regulation of cholesterol homeostasis and inflammatory response in atherosclerosis

Atherosclerosis (AS) is characterized by lipids metabolism disorder and inflammatory response. Accumulating evidence has demonstrated that Wingless type 5a (Wnt5a) is implicated in cardiovascular diseases through non-canonical Wnt cascades. However, its precise role during the pathogenesis of AS is still unclear. Therefore, the present study aims to investigate the role and the underlying mechanism of Wnt5a/receptor tyrosine kinase-like orphan receptor 2 (Ror2) pathways in the promotion of AS process through affecting lipid accumulation and inflammation. In atherosclerotic clinical samples, Wnt5a levels were measured by using enzyme-linked immunosorbent assay (ELISA) assay. In vivo experiments were conducted by using apolipoprotein E knockout (apoE^-/-) mice model. Vascular smooth muscle cells (VSMCs) were applied for in vitro studies. Wnt5a was highly expressed in both of atherosclerotic clinical samples and apoE^-/- mice. The knockdown of Wnt5a significantly inhibited cholesterol accumulation and inflammatory response. Additionally, the lipopolysaccharide (LPS)-induced inflammation aggravated the cholesterol accumulation and decreased adenosine triphosphate (ATP)-binding cassette transporter A1 (ABCA1) expression in VSMCs. Depletion of intracellular cholesterol by β-cyclodextrin (β-CD) led to the upregulation of ABCA1 and the inhibition of inflammation. Conversely, the overexpression of Wnt5a inhibited ABCA1 expression, facilitated cholesterol accumulation, impared cholesterol efflux, promoted NF-κB nuclear translocation and the inflammatory cytokines secretion. Moreover, the knockdown of Ror2 increased ABCA1 expression and reduced Wnt5a-induced cholesterol accumulation and inflammatory responses. Furthermore, the knockdown of ABCA1 enhanced cholesterol accumulation and inflammatory response. Therefore, Wnt5a/Ror2 pathway was critical in regulating cholesterol homeostasis and inflammatory response, which might be a promising therapeutic target for AS therapy.

Activation of GPR39 with the agonist TC-G 1008 ameliorates ox-LDL-induced attachment of monocytes to endothelial cells

Attachment of monocytes to endothelial cells is a major event in the pathogenesis of atherosclerosis and cardiovascular disease. As atherosclerosis is considered to be an inflammatory disease, increased expression of proinflammatory cytokines greatly contributes to endothelial dysfunction and atherogenesis. Additionally, attachment of monocytes to endothelial cells triggered by cellular adhesion molecules such as vascular cellular adhesion molecule 1 (VCAM-1) and E-selectin plays a vital role in the development of atherosclerotic plaques. Zinc therapy has been suggested as a potential strategy for countering atherosclerosis. In the present study, for the first time to our knowledge, we investigated the potential role of the GPR39 zinc-sensing receptor in mediating the adhesion of monocytes to endothelial cells, oxidative stress and inflammation in human aortic endothelial cells induced by oxidized low-density lipoprotein (ox-LDL). Our findings show that agonism of GPR39 by the selective agonist TC-G 1008 potently reversed the effects of ox-LDL including increased expression of proinflammatory cytokines and chemokines, markers of oxidative stress, and enhanced expression of cellular adhesion molecules. Importantly, we also show that this protective effect is mediated through the nuclear factor-κB (NF-κB) pathway. Taken together, our findings suggest a potential role of GPR39 as a novel therapeutic target for the treatment and prevention of atherosclerosis induced by ox-LDL.

Chrysin Suppresses Vascular Endothelial Inflammation via Inhibiting the NF-κB Signaling Pathway

The vascular endothelium is a continuous layer of flat polygonal cells that are in direct contact with the blood and participate in responses to inflammation. Chrysin is a flavonoid compound extracted from plants of the genus Asteraceae with a wide range of pharmacological activities and physiological activities. Here, we studied the effects of chrysin on the regulation of the proadhesion and pro-inflammatory phenotypes of the endothelium both in vitro and in vivo. Our results revealed that chrysin strongly inhibited Tohoku Hospital Pediatrics-1 (THP-1) cell adhesion to primary human umbilical vein endothelial cells and concentration-dependently attenuated interleukin 1β-induced increases in intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and E-selectin messenger RNA levels and ICAM-1 and VCAM-1 protein levels. Previous studies reported that nuclear factor κB (NF-κB) is important in the inflammatory response in endothelial cells, particularly in regulating adhesion molecules, and our data shed light on the mechanisms whereby chrysin suppressed endothelial inflammation via the NF-κB signaling pathway. In addition, our in vivo findings demonstrated the effects of chrysin in the permeability and inflammatory responses of the endothelium to inflammatory injury. Taken together, we conclude that chrysin inhibits endothelial inflammation both in vitro and in vivo, which could be mainly due to its inhibition of NF-κB signaling activation. In conclusion, chrysin may serve as a promising therapeutic candidate for inflammatory vascular diseases.

Deletion of IκB-Kinase β in Smooth Muscle Cells Induces Vascular Calcification Through β-Catenin-Runt-Related Transcription Factor 2 Signaling

BACKGROUND

Vascular calcification was previously considered as an advanced phase of atherosclerosis; however, recent studies have indicated that such calcification can appear in different situations. Nevertheless, there has been a lack of mechanistic insight to explain the difference. For example, the roles of nuclear factor-κB, a major regulator of inflammation, in vascular calcification are poorly explored, although its roles in atherosclerosis were well documented. Herein, we investigated the roles of nuclear factor-κB signaling in vascular calcification.

METHODS AND RESULTS

We produced mice with deletion of IKKβ, an essential kinase for nuclear factor-κB activation, in vascular smooth muscle cells (VSMCs; KO mice) and subjected them to the CaCl₂-induced aorta injury model. Unexpectedly, KO mice showed more calcification of the aorta than their wild-type littermates, despite the former's suppressed nuclear factor-κB activity. Cultured VSMCs from the aorta of KO mice also showed significant calcification in vitro. In the molecular analysis, we found that Runt-related transcription factor 2, a transcriptional factor accelerating bone formation, was upregulated in cultured VSMCs from KO mice, and its regulator β-catenin was more activated with suppressed ubiquitination in KO VSMCs. Furthermore, we examined VSMCs from mice in which kinase-active or kinase-dead IKKβ was overexpressed in VSMCs. We found that kinase-independent function of IKKβ is involved in suppression of calcification via inactivation of β-catenin, which leads to suppression of Runt-related transcription factor 2 and osteoblast marker genes.

CONCLUSIONS

IKKβ negatively regulates VSMC calcification through β-catenin-Runt-related transcription factor 2 signaling, which revealed a novel function of IKKβ on vascular calcification.

Baicalin alleviates atherosclerosis by relieving oxidative stress and inflammatory responses via inactivating the NF-κB and p38 MAPK signaling pathways

Atherosclerosis (AS) is a chronic progressive disease related to inflammatory reaction. Baicalin is a flavonoid isolated from Scutellaria baicalensis georgi (Huang-qin) and exerts anti-inflammation effects in various diseases. Here, we investigated the protective effects of baicalin treatment and the potential mechanism in AS progression on AS mouse model. After ApoE-/- mice with high-lipid diets had received 12 weeks' of baicalin treatment at different concentrations, plasma lipids levels and atherosclerotic plaque areas in aorta were measured and there exhibited a prominent improvement in the baicalin treated mice compared with mice in AS model group. The expression of lipolysis related proteins (PPARα, CPT-1) was increased while the expression of adipogenesis related proteins (SREBP-1c, ACS) was decreased by baicalin treatment, indicating the anti-adipogenic effect of baicalin. Moreover, baicalin up-regulated the activities of antioxidant enzymes (SOD, CAT and GSH-Px) and down-regulated the activity of oxidative parameter MDA compared with AS model group, indicating the anti-oxidant effect of baicalin. The increased levels of pro-inflammatory cytokines (IL-6, TNF-α, sVE-cadherin) induced by AS were also decreased by baicalin treatment, indicating that baicalin acted as an anti-inflammation regulator in AS. In addition, we further explored the potential mechanism of baicalin treatment on AS, and found that baicalin treatment attenuated the high phosphorylation levels of JNK, p65, p-38 and ERK1/2 induced by AS, indicating that baicalin treatment inhibited the NF-κB and p38 MAPK signaling pathways in AS. In conclusion, baicalin treatment inhibited the NF-κB and p38 MAPK signaling pathways, thereby achieved its anti-adipogenic effect, anti-oxidant effect and anti-inflammation effect in a dose-dependent manner in AS.

Antiatherogenic Roles of Dietary Flavonoids Chrysin, Quercetin, and Luteolin

Cardiovascular diseases (CVDs) are the commonest cause of global mortality and morbidity. Atherosclerosis, the fundamental pathological manifestation of CVDs, is a complex process and is poorly managed both in terms of preventive and therapeutic intervention. Aberrant lipid metabolism and chronic inflammation play critical roles in the development of atherosclerosis. These processes can be targeted for effective management of the disease. Although managing lipid metabolism is in the forefront of current therapeutic approaches, controlling inflammation may also prove to be crucial for an efficient treatment regimen of the disease. Flavonoids, the plant-derived polyphenols, are known for their antiinflammatory properties. This review discusses the possible antiatherogenic role of 3 flavonoids, namely, chrysin, quercetin, and luteolin primarily known for their antiinflammatory properties.

Pro-apoptotic effects of lipid oxidation products: HNE at the crossroads of NF-κB pathway and anti-apoptotic Bcl-2

The axis between lipid oxidation products and cell death is explicitly linked. 4-Hydroxynonenal (HNE), as well as other lipid oxidation products was also established to induce apoptosis in various experimental settings. Yet, the decision leading to apoptotic execution not only includes upregulation of pro-apoptotic signals but also involves a downregulation of anti-apoptotic signals. Within the frames of this paradigm, HNE acts significantly different from other lipid oxidation products in the regulation of two widely known anti-apoptotic elements, Nuclear Factor-κB (NF-κB) transcription factors and its target anti-apoptotic B-Cell Lymphoma-2 (Bcl-2) protein. Even so, a review inclusively linking these anti-apoptotic factors and their crosstalk upon HNE exposure is still at demand. In order to elucidate presence of such crosstalk, reports on the link between HNE and NF-κB pathway, on the link between HNE and anti-apoptotic Bcl-2 and on the crossroad of these links during HNE exposure were summarized and discussed. IKK, the upstream kinase of NF-κB, has been shown to regulate HNE mediated phosphorylation and inactivation of Bcl-2 by our group. Based on this observation and other studies reporting on HNE-NF-κB pathway interaction, IKK was proposed to mediate the crosstalk of NF-κB pathway and anti-apoptotic Bcl-2 protein, when HNE is present. These reports further suggested that HNE based inhibition of NF-κB pathway is highly likely. Besides, evidence on the HNE-anti-apoptotic Bcl-2 axis supported the deduction of HNE mediated NF-κB pathway inhibition and IKK mediated Bcl-2 inactivation. In conclusion, through combining all evidences, three possible scenarios intervening the HNE mediated crosstalk between NF-κB pathway and anti-apoptotic Bcl-2 protein, was extrapolated.

Sodium azide suppresses LPS-induced expression MCP-1 through regulating IκBζ and STAT1 activities in macrophages

Sodium azide (NaN₃) is a chemical compound with multiple toxic effects on vascular and neuronal systems, causing hypotension and neurotoxicity, respectively. In order to test its effects on the immune system, human and mouse macrophage-like cell lines were treated with nontoxic doses of NaN₃ and the changes in LPS-induced inflammatory activation was measured. Interestingly, the LPS-induced expression of monocyte chemoattractant protein (MCP)-1 was suppressed by NaN₃ without affecting the expression of IL-8 and TNF-α. Further analysis of cellular signaling mediators involved in the expression of these cytokines revealed that NaN₃ suppressed the LPS-induced activation of signal transducers and activator of transcription (STAT)1 and inhibitor of κB (IκB) ς, which are involved in the LPS-induced expression of MCP-1, while the LPS-induced activation of nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) was not affected. The LPS-induced expression of MCP-2 and CXCL10, which are also regulated by STAT1, was suppressed by NaN₃. Similarly, the LPS-induced expression of IL-6, which is regulated by IκBζ, was suppressed by NaN₃. These results demonstrate that NaN₃ selectively suppresses the LPS-induced expression of pro-inflammatory mediators through the suppression of STAT1 and IκBζ activation. These new findings about the activity of NaN₃ may contribute to the development of specific regulators of macrophage activity during acute and chronic inflammation.

Leonurine, a Potential Agent of Traditional Chinese Medicine: Recent Updates and Future Perspectives

Herba Leonuri, also named Chinese Motherwort, has been extensively investigated as an effective agent on the uterus system. Our group has been studying the natural products of Herba Leonuri for several years, and during this period, many biological activities of the drug were recognized. Leonurine (4-guanidino- N-butyl-syringate) is an alkaloid present in Herba Leonuri. Recently, growing evidence has highlighted the therapeutic potential of leonurine in multiple diseases, especially cardiovascular. In this review, we discuss the biological activities of leonurine, as well as recent advances involving this alkaloid.

Tanshinone II A stabilizes vulnerable plaques by suppressing RAGE signaling and NF-κB activation in apolipoprotein-E-deficient mice

Tanshinone II A (TSIIA) is a diterpene quinone extracted from the roots of Salvia miltiorrhiza with anti-inflammatory and anti-oxidant properties that is used to treat atherosclerosis. In the current study, morphological analyses were conducted to evaluate the effects of TSIIA on atherosclerotic vulnerable plaque stability. Additionally, receptor of advanced glycation end products (RAGE), adhesion molecule, and matrix-metalloproteinases (MMPs) expression, and nuclear factor-κB (NF-κB) activation were examined in apolipoprotein E (apoE)-deficient mice treated with TSIIA. Eight-week-old apoE^−/− mice were administered TSIIA and fed an atherogenic diet for 8 weeks. TSIIA exhibited no effects on plaque size. Analysis of the vulnerable plaque composition demonstrated decreased numbers of macrophages and smooth muscle cells, and increased collagen content in apoE-deficient mice treated with TSIIA compared with untreated mice. Western blotting revealed that TSIIA downregulated the expression levels of vascular cellular adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and MMP-2, −3, and −9, suppressed RAGE, and inhibited NF-κB, JNK and p38 activation. The present study demonstrated that the underlying mechanism of TSIIA stabilization of vulnerable plaques involves interfering with RAGE and NF-κB activation, and downregulation of downstream inflammatory factors, including ICAM-1, VCAM-1, and MMP-2, −3 and −9 in apoE^−/− mice.

Astragaloside IV ameliorates necrotizing enterocolitis by attenuating oxidative stress and suppressing inflammation via the vitamin D3-upregulated protein 1/NF-κB signaling pathway

Astragaloside IV (AS-IV) is a flavonoid from the plant Astragalus membranaceus (Fisch) Bge that has a wide range of therapeutic effects. The aim of the present study was to examine the effect of AS-IV on rats with necrotizing enterocolitis (NEC) under oxidative stress and inflammation. Newborn Sprague-Dawley rats were induced with NEC by asphyxia and hypothermia applied on 3 consecutive days. The rats were orally administered AS-IV at 25, 50 and 75 mg/kg for 4 days. The results revealed that AS-IV administration prevented NEC-induced decrease in the concentration of malondialdehyde and myeloperoxidase, and increase in the activity of glutathione (GSH) and superoxide dismutase in murine models. AS-IV also inhibited NEC-induced elevation in the levels of interleukin (IL)-6, IL-1β, tumor necrosis factor-α and nuclear factor (NF)-κB. The effects of AS-IV were achieved under inflammation and oxidative stress. Western blotting demonstrated that AS-IV substantially inhibited the phosphorylated (p)-IκBα, NF-κBp65, p-NF-κBp65 protein levels and increased vitamin D3 upregulated protein 1 (VDUP1) and IκBα protein levels. These data indicate that AS-IV may be effective in the protection of NEC-induced ileum degeneration by inhibiting the levels of inflammatory markers and oxidative stress via the regulation of the VDUP1/NF-κB signaling pathway.

Early Onset of Atherosclerosis of The Carotid Bifurcation in Newborn Cadavers

INTRODUCTION

The anatomy of arterial bifurcations affects blood flow and has a significant role in the development of vascular disease. Therefore, it is important to know the structural characteristics of the Common Carotid Artery (CCA) and its branches for early onset of atherosclerosis in newborns.

AIM

The present study was conducted to evaluate the characteristics of CCA in newborn cadavers.

MATERIALS AND METHODS

Eight carotid arteries obtained from newborn cadavers were used. The outflow to inflow area ratios was calculated to evaluate vessel diameters. Additionally, scanning electron and light microscopic investigations were conducted with tissue samples. The brachial artery of each cadaver was used as controls. Correlation between area ratios and atherosclerotic endothelial damage was determined.

RESULTS

Light microscopic investigations demonstrated that control group sections showed no positivity for Oil red O staining, while carotid bifurcation regions depicted widespread occurrence of intimal lipid accumulations. Scanning electron microscopic examination of control group sections presented regular endothelial topography, while carotid bifurcation region topography exhibited numerous blood cells and separated endothelial cells. Fibrin accumulation on endothelial surface in low area ratios was another important finding in the examination of its endothelial surface degeneration. The above-mentioned morphological findings seemed to be quite parallel to outflow to inflow area ratio data favouring low area and degeneration.

CONCLUSION

The correlation between area ratios and the histological characteristic of cerebral vessels of newborn cadavers indicate that early stages of atherosclerosis began in early embryologic life.

An experimental evaluation of the anti-atherogenic potential of the plant, Piper betle, and its active constitutent, eugenol, in rats fed an atherogenic diet

Hypercholesterolemia is a major risk factor for systemic atherosclerosis and subsequent cardiovascular disease. Lipoperoxidation-mediated oxidative damage is believed to contribute strongly to the progression of atherogenesis. In the current investigation, putative anti-atherogenic and antioxidative properties of an ethanolic extract of Piper betle and of its active constituent, eugenol, were sought in an experimental animal model of chronic hypercholesterolemia. Atherogenic diet-fed rats that received either Piper betle extract orally (500mg/kg b.wt) or eugenol orally (5mg/kg b.wt) for 15days (commencing 30days after the atherogenic diet had been started) exhibited the following variations in different parameters, when compared to atherogenic diet-fed rats that received only saline: (1) significantly lower mean levels of total cholesterol, triglycerides, low-density lipoprotein cholesterol and very low density lipoprotein cholesterol in both serum and hepatic tissue samples; (2) lower mean serum levels of aspartate amino-transferase, alanine amino-transferase, alkaline phosphatase, lactate dehydrogenase and lipid-metabolizing enzymes (lipoprotein lipase, 3-hydroxy-3-methyl-glutaryl-CoA reductase; (3) significantly lower mean levels of enzymatic antioxidants (catalase, superoxide dismutase, glutathione peroxidase, glutathione-S-transferase) and non-enzymatic antioxidants (reduced glutathione, vitamin C and vitamin E) and significantly higher mean levels of malondialdehyde in haemolysate and hepatic tissue samples. Histopathological findings suggested a protective effect of the Piper betle extract and a more pronounced protective effect of eugenol on the hepatic and aortic tissues of atherogenic diet-fed (presumed atherosclerotic) rats. These results strongly suggest that the Piper betle extract and its active constituent, eugenol, exhibit anti-atherogenic effects which may be due to their anti-oxidative properties.

Virgin olive oil rich in phenolic compounds modulates the expression of atherosclerosis-related genes in vascular endothelium

PURPOSE

Previous studies have shown the anti-inflammatory and antioxidant properties of phenolic compounds of virgin olive oil (VOO). However, the effect of bioavailable phenolic compounds on the vascular endothelium is unknown. We aimed to evaluate the effect of the consumption of virgin olive oil rich in phenolic compounds on the vascular endothelium.

METHODS

We treated HUVEC with human serum obtained in fasting state and after the intake of a breakfast prepared with VOO with a high or low content of phenolic compounds.

RESULTS

Treatment of HUVEC with serum obtained 2 h after the intake of the high-phenol VOO-based breakfast decreased p65 and MCP-1 gene expression (p < 0.001 and p = 0.002, respectively) and increased MT-CYB, SDHA and SOD1 gene expression (p = 0.004, p = 0.012 and p = 0.001, respectively), as compared with the treatment of HUVEC with the serum obtained 2 h after the intake of the low-phenol VOO-based breakfast. The treatment with serum obtained 4 h after the intake of the high-phenol VOO-based breakfast decreased MCP-1 and CAT gene expression (p < 0.001 and p = 0.003, respectively) and increased MT-CYB gene expression (p < 0.001), as compared to the treatment with serum obtained 4 h after the intake of the low-phenol VOO-based breakfast.

CONCLUSION

Our results suggest that the consumption of virgin olive oil rich in phenolic compounds may reduce the risk of atherosclerosis development by decreasing inflammation and improving the antioxidant profile in the vascular endothelium.

Role of mitochondrial reactive oxygen species in age-related inflammatory activation of endothelium

Vascular aging is accompanied by increases in circulatory proinflammatory cytokines leading to inflammatory endothelial response implicated in early atherogenesis. To study the possible role of mitochondria-derived reactive oxygen species (ROS) in this phenomenon, we applied the effective mitochondria-targeted antioxidant SkQ1, the conjugate of plastoquinone with dodecyltriphenylphosphonium. Eight months treatment of (CBAxC57BL/6) F1 mice with SkQ1 did not prevent age-related elevation of the major proinflammatory cytokines TNF and IL-6 in serum, but completely abrogated the increase in adhesion molecule ICAM1 expression in aortas of 24-month-old animals. In endothelial cell culture, SkQ1 also attenuated TNF-induced increase in ICAM1, VCAM, and E-selectin expression and secretion of IL-6 and IL-8, and prevented neutrophil adhesion to the endothelial monolayer. Using specific inhibitors to transcription factor NF-κB and stress-kinases p38 and JNK, we demonstrated that TNF-induced ICAM1 expression depends mainly on NF-κB activity and, to a lesser extent, on p38. SkQ1 had no effect on p38 phosphorylation (activation) but significantly reduced NF-κB activation by inhibiting phosphorylation and proteolytic cleavage of the inhibitory subunit IκBα. The data indicate an important role of mitochondrial reactive oxygen species in regulation of the NF-κB pathway and corresponding age-related inflammatory activation of endothelium.

siRNA-mediated silencing of Wnt5a regulates inflammatory responses in atherosclerosis through the MAPK/NF-κB pathways

Previous studies have demonstrated that the aberrant expression of Wnt5a occurs in atherosclerotic lesions. However, the precise role of Wnt5a in the pathogenesis of atherosclerosis remains largely unknown. The present study was undertaken to determine whether the RNA interference of Wnt5a in vivo by adenovirus (Ad)-mediated small interfering RNA (siRNA) transfection is capable of inhibiting the progression of atherosclerosis. Recombinant adenovirus carrying siRNA targeting Wnt5a (Ad-Wnt5a siRNA) was designed. Male apolipoprotein E-deficient (ApoE(-/-)) mice were fed a high-fat diet to induce the pathogenesis of atherosclerosis. Mice were randomly divided into 3 groups (n=15 in each group): the mock group, which received treatment with phosphate-buffered saline (PBS); the Ad-NC group, which received treatment with Ad-non-specific siRNA; and the Ad-Wnt5a siRNA group, which received treatment with Ad-Wnt5a siRNA. Treatment with Ad-Wnt5a siRNA markedly inhibited the mRNA and protein expression of Wnt5a in the aortic tissues. The knockdown of Wnt5a had no significant effect on blood lipid levels, but it suppressed atherosclerotic development and increased plaque stability, which was determined by hematoxylin and eosin staining, picrosirius red staining and Oil Red O staining. Furthermore, the mRNA and protein expression of inflammatory cytokines, including monocyte chemotactic protein-1 (MCP-1), cyclooxygenase-2 (COX-2), matrix metalloproteinase (MMP)-2 and MMP-9 was significantly downregulated in the Ad-Wnt5a siRNA group. In addition, the knockdown of Wnt5a inhibited the nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. These results demonstrate that Ad-mediated Wnt5a silencing in vivo attenuates the development of atherosclerotic disease by reducing inflammatory mediators involved in the MAPK/NF-κB pathways.

Homocysteine induces the expression of C-reactive protein via NMDAr-ROS-MAPK-NF-κB signal pathway in rat vascular smooth muscle cells

OBJECTIVE

Homocysteine (Hcy) is known as an independent risk factor for atherosclerosis. C-reactive protein (CRP) directly participates in initiation and progression of atherosclerosis. However, there is no direct evidence to demonstrate pro-inflammatory effect of Hcy on vascular smooth muscle cells (VSMCs) through CRP. In the present study, we examined the effect of Hcy on CRP expression and investigated the related mechanism in VSMCs.

METHODS AND RESULTS

Protein expression and secretion were detected by Western blot and ELISA, respectively. mRNA expression was detected by RT-PCR. Superoxide anion was detected by lucigenin chemiluminometry and the immunofluorescence staining was observed by a fluorescence microscope. The results revealed that Hcy significantly induced mRNA and protein expressions of CRP in VSMCs both in vitro and in vivo, and anti-IL-1β or anti-IL-6 neutralizing antibody alone or in combination partially reduced Hcy-induced CRP expression. Hcy increased the expression of NR1 subunit of N-methyl-d-aspartate receptor (NMDAr), and MK-801 alleviated Hcy-induced CRP expression in VSMCs. Further studies showed that Hcy-stimulated superoxide anion generation in VSMCs. Nevertheless, pretreatment of the cells with MK-801, TTFA and DPI significantly reduced Hcy-stimulated superoxide anion generation, and antioxidant NAC decreased Hcy-induced CRP expression in VSMCs. Additionally, PD98059, SB205380 or PDTC antagonized Hcy-induced CRP expression, and MK-801, NAC, PD98059 or SB205380 inhibited Hcy-activated phosphorylations of ERK1/2 and p38.

CONCLUSION

The present study demonstrates that Hcy is able to initiate an inflammatory response in VSMCs by stimulating CRP production, which is mediated through NMDAr-ROS-ERK1/2/p38-NF-κB signal pathway. These findings provide new evidence for a role of Hcy in pathogenesis of atherosclerosis.

Vaspin inhibits cytokine-induced nuclear factor-kappa B activation and adhesion molecule expression via AMP-activated protein kinase activation in vascular endothelial cells

Background

Vaspin is an adipocytokine that was recently identified in the visceral adipose tissue of diabetic rats and has anti-diabetic and anti-atherogenic effects. We hypothesized that vaspin prevents inflammatory cytokine-induced nuclear factor-kappa B (NF-κB) activation by activating AMP-activated protein kinase (AMPK) in vascular endothelial cells.

Methods

We examined the effects of vaspin on NF-κB activation and the expression of the NF-κB-mediated genes intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, and monocyte chemoattractant protein-1 (MCP-1). Human aortic endothelial cells (HAECS) were used. Tumor necrosis factor alpha (TNFα) was used as a representative proinflammatory cytokine.

Results

Treatment with vaspin significantly increased the phosphorylation of AMPK and acetyl-CoA carboxylase, the down-stream target of AMPK. Furthermore, treatment with vaspin significantly decreased TNFα-induced activation of NF-κB, as well as the expression of the adhesion molecules ICAM-1, VCAM-1, E-selectin, and MCP-1. These effects were abolished following transfection of AMPKα1-specific small interfering RNA. In an adhesion assay using THP-1 cells, vaspin reduced TNFα-induced adhesion of monocytes to HAECS in an AMPK-dependent manner.

Conclusions

Vaspin might attenuate the cytokine-induced expression of adhesion molecule genes by inhibiting NF-κB following AMPK activation.

Evidence for novel genetic loci associated with metabolic traits in Yup'ik people

OBJECTIVES

To identify genomic regions associated with fasting plasma lipid profiles, insulin, glucose, and glycosylated hemoglobin in a Yup'ik study population, and to evaluate whether the observed associations between genetic factors and metabolic traits were modified by dietary intake of marine derived omega-3 polyunsaturated acids (n-3 PUFA).

METHODS

A genome-wide linkage scan was conducted among 982 participants of the Center for Alaska Native Health Research study. n-3 PUFA intake was estimated using the nitrogen stable isotope ratio (δ(15) N) of erythrocytes. All genotyped SNPs located within genomic regions with LOD scores > 2 were subsequently tested for individual SNP associations with metabolic traits using linear models that account for familial correlation as well as age, sex, community group, and n-3 PUFA intake. Separate linear models were fit to evaluate interactions between the genotype of interest and n-3 PUFA intake.

RESULTS

We identified several chromosomal regions linked to serum apolipoprotein A2, high density lipoprotein-, low density lipoprotein-, and total cholesterol, insulin, and glycosylated hemoglobin. Genetic variants found to be associated with total cholesterol mapped to a region containing previously validated lipid loci on chromosome 19, and additional novel peaks of biological interest were identified at 11q12.2-11q13.2. We did not observe any significant interactions between n-3 PUFA intake, genotypes, and metabolic traits.

CONCLUSIONS

We have completed a whole genome linkage scan for metabolic traits in Native Alaskans, confirming previously identified loci, and offering preliminary evidence of novel loci implicated in chronic disease pathogenesis in this population.

IKKε knockout prevents high fat diet induced arterial atherosclerosis and NF-κB signaling in mice

AIMS

Atherosclerosis is a public health concern affecting many worldwide, but its pathogenesis remains unclear. In this study we investigated the role of IKKε during the formation of atherosclerosis and its molecular mechanism in the mouse aortic vessel wall.

METHODS AND RESULTS

C57BL/6 wild-type or IKKε knockout mice bred into the ApoE knockout genetic background were divided into 4 groups: (1) wild-type (WT), (2) ApoE knockout (AK), (3) IKKε knockout (IK), (4) or both ApoE and IKKε knockout (DK). Each group of mice were fed with a high fat diet (HFD) for 12 weeks from 8 weeks of age. Immunohistochemistry and Western blotting analysis demonstrated obvious increases in the expression of IKKε in the AK group compared with the WT group, especially in the intima. Serum lipid levels were significantly higher in the AK and DK groups than in the other two groups. Staining with hematoxylin-eosin and Oil Red, as well as scanning electron microscopy revealed less severe atherosclerotic lesions in the DK group than in the AK group. Immunofluorescence and Western blot analysis demonstrated obvious increases in the expression of NF-κB pathway components and downstream factors in the AK group, especially in the intima, while these increases were blocked in the DK group.

CONCLUSION

The knockout of IKKε prevented significant atherosclerosis lesions in the mouse aorta from in both wild-type and ApoE knockout mice fed a HFD, suggesting that IKKε may play a vital role in HFD-induced atherosclerosis and would be an important target for the treatment of atherosclerosis.

Inflammation and oxidative stress in angiogenesis and vascular disease

Recent evidence suggests that processes of inflammation and angiogenesis are interconnected, especially in human pathologies. Newly formed blood vessels enable the continuous recruitment of inflammatory cells, which release a variety of proangiogenic cytokines, chemokines, and growth factors and further promote angiogenesis. These series of positive feedback loops ultimately create a vicious cycle that exacerbates inflammation, transforming it into the chronic process. Recently, this concept of reciprocity of angiogenesis and inflammation has been expanded to include oxidative stress as a novel mechanistic connection between inflammation-driven oxidation and neovascularization. Production of reactive oxygen species results from activation of immune cells by proinflammatory stimuli. As oxidative stress can lead to chronic inflammation by activating a variety of transcription factors including NF-κB, AP-1, and PPAR-γ, inflammation itself has a reciprocal relationship with oxidative stress. This review discusses the recent findings in the area bridging neovascularization and oxidation and highlights novel mechanisms of inflammation- and oxidative stress-driven angiogenesis.

Grape resveratrol increases serum adiponectin and downregulates inflammatory genes in peripheral blood mononuclear cells: a triple-blind, placebo-controlled, one-year clinical trial in patients with stable coronary artery disease

PURPOSE

The grape and wine polyphenol resveratrol exerts cardiovascular benefits but evidence from randomized human clinical trials is very limited. We investigated dose-depending effects of a resveratrol-containing grape supplement on stable patients with coronary artery disease (CAD) treated according to currently accepted guidelines for secondary prevention of cardiovascular disease.

METHODS

In a triple-blind, randomized, placebo-controlled, one-year follow-up, 3-arm pilot clinical trial, 75 stable-CAD patients received 350 mg/day of placebo, resveratrol-containing grape extract (grape phenolics plus 8 mg resveratrol) or conventional grape extract lacking resveratrol during 6 months, and a double dose for the following 6 months. Changes in circulating inflammatory and fibrinolytic biomarkers were analyzed. Moreover, the transcriptional profiling of inflammatory genes in peripheral blood mononuclear cells (PBMCs) was explored using microarrays and functional gene expression analysis.

RESULTS

After 1 year, in contrast to the placebo and conventional grape extract groups, the resveratrol-containing grape extract group showed an increase of the anti-inflammatory serum adiponectin (9.6 %, p = 0.01) and a decrease of the thrombogenic plasminogen activator inhibitor type 1 (PAI-1) (-18.6 %, p = 0.05). In addition, 6 key inflammation-related transcription factors were predicted to be significantly activated or inhibited, with 27 extracellular-space acting genes involved in inflammation, cell migration and T-cell interaction signals presenting downregulation (p < 0.05) in PBMCs. No adverse effects were detected in relation to the study products.

CONCLUSIONS

Chronic daily consumption of a resveratrol-containing grape nutraceutical could exert cardiovascular benefits in stable-CAD patients treated according to current evidence-based standards, by increasing serum adiponectin, preventing PAI-1 increase and inhibiting atherothrombotic signals in PBMCs.

Redox-inflammatory synergy in the metabolic syndrome

Metabolic syndrome (MetS) comprises interrelated disease states including obesity, insulin resistance and type 2 diabetes (T2DM), dyslipidemia, and hypertension. Essential to normal physiological function, and yet massively damaging in excess, oxidative stress and inflammation are pivotal common threads among the pathologies of MetS. Increasing evidence indicates that redox and inflammatory dysregulation parallels the syndrome's physiological, biochemical, and anthropometric features, leading many to consider the pro-oxidative, pro-inflammatory milieu an unofficial criterion in itself. Left unchecked, cross-promotion of oxidative stress and inflammation creates a feed-forward cycle that can initiate and advance disease progression. Such redox-inflammatory integration is evident in the pathogenesis of obesity, insulin resistance and T2DM, atherogenic dyslipidemia, and hypertension, and is thus hypothesized to be the "common soil" from which they develop. The present review highlights the synergistic contributions of redox-inflammatory processes to each of the components of the MetS.

Calpain and atherosclerosis

This review highlights the pro-atherogenic roles of Ca(2+)-sensitive intracellular protease calpains. Among more than ten species of calpain isozymes, µ- and m-calpains have been characterized most extensively. These two isozymes are ubiquitously expressed in mammalian tissues, including blood vessels, and tightly regulate functional molecules in the vascular component cells through limited proteolytic cleavage. Indeed, previous cell-based experiments showed that calpains play significant roles in nitric oxide production in vascular endothelial cells (ECs), maintenance of EC barrier function and angiogenesis for maintaining vascular homeostasis. Recently, we demonstrated that modified-low density lipoprotein (LDL)-induced m-calpain causes hyperpermeability in ECs, leading to the infiltration of monocytes/macrophages and plasma lipids into the intimal spaces (Miyazaki T. et al., Circulation. 2011; 124: 2522-2532). Calpains also mediate oxidized LDL-induced apoptotic death in ECs. In monocytes/macrophages, calpains induce proteolytic degradation of ATP-binding cassette transporter A1 (ABCA1) and G1 (ABCG1), which results in impaired cholesterol efflux and subsequent macrophage foam cell formation. In vascular smooth muscle cells, calpains may be involved in the conversion from contractile phenotype to proliferative phenotype. In hepatocytes, calpains disrupt the biogenesis of high-density lipoprotein via proteolytic degradation of ABCA1. Thus, calpains may serve as novel candidate molecular targets for control of atherosclerosis.