Atorvastatin improves plaque stability in ApoE-knockout mice by regulating chemokines and chemokine receptors

Selective deletion of E3 ubiquitin ligase FBW7 in VE-cadherin-positive cells instigates diffuse large B-cell lymphoma in mice in vivo

During the maturation of hematopoietic stem/progenitor cells (HSPCs) to fully differentiated mature B lymphocytes, developing lymphocytes may undergo malignant transformation and produce B-cell lymphomas. Emerging evidence shows that through the endothelial-hematopoietic transition, specialized endothelial cells called the hemogenic endothelium can differentiate into HSPCs. However, the contribution of genetic defects in hemogenic endothelial cells to B-cell lymphomagenesis has not yet been investigated. Here, we report that mice with endothelial cell-specific deletion of Fbw7 spontaneously developed diffuse large B-cell lymphoma (DLBCL) following Bcl6 accumulation. Using lineage tracing, we showed that B-cell lymphomas in Fbw7 knockout mice were hemogenic endothelium-derived. Mechanistically, we found that FBW7 directly interacted with Bcl6 and promoted its proteasomal degradation. FBW7 expression levels are inversely correlated with BCL6 expression. Additionally, pharmacological disruption of Bcl6 abolished Fbw7 deletion-induced B-cell lymphomagenesis. We conclude that selective deletion of E3 ubiquitin ligase FBW7 in VE-cadherin positive endothelial cells instigates diffuse large B-cell lymphoma via upregulation of BCL6 stability. In addition, the mice with endothelial cell-specific deletion of Fbw7 provide a valuable preclinical platform for in vivo development and evaluation of novel therapeutic interventions for the treatment of DLBCL.

Transient increase in atherosclerotic plaque macrophage content following Streptococcus pneumoniae pneumonia in ApoE-deficient mice

Introduction

Despite epidemiological associations between community acquired pneumonia (CAP) and myocardial infarction, mechanisms that modify cardiovascular disease during CAP are not well defined. In particular, largely due to a lack of relevant experimental models, the effect of pneumonia on atherosclerotic plaques is unclear. We describe the development of a murine model of the commonest cause of CAP, Streptococcus pneumoniae pneumonia, on a background of established atherosclerosis. We go on to use our model to investigate the effects of pneumococcal pneumonia on atherosclerosis.

Methods

C57BL/6J and ApoE-/- mice were fed a high fat diet to promote atherosclerotic plaque formation. Mice were then infected with a range of S. pneumoniae serotypes (1, 4 or 14) with the aim of establishing a model to study atherosclerotic plaque evolution after pneumonia and bacteremia. Laser capture microdissection of plaque macrophages enabled transcriptomic analysis.

Results

Intratracheal instillation of S. pneumoniae in mice fed a cholate containing diet resulted in low survival rates following infection, suggestive of increased susceptibility to severe infection. Optimization steps resulted in a final model of male ApoE-/- mice fed a Western diet then infected by intranasal instillation of serotype 4 (TIGR4) S. pneumoniae followed by antibiotic administration. This protocol resulted in high rates of bacteremia (88.9%) and survival (88.5%). Pneumonia resulted in increased aortic sinus plaque macrophage content 2 weeks post pneumonia but not at 8 weeks, and no difference in plaque burden or other plaque vulnerability markers were found at either time point. Microarray and qPCR analysis of plaque macrophages identified downregulation of two E3 ubiquitin ligases, Huwe1 and Itch, following pneumonia. Treatment with atorvastatin failed to alter plaque macrophage content or other plaque features.

Discussion

Without antibiotics, ApoE-/- mice fed a high fat diet were highly susceptible to mortality following S. pneumoniae infection. The major infection associated change in plaque morphology was an early increase in plaque macrophages. Our results also hint at a role for the ubiquitin proteasome system in the response to pneumococcal infection in the plaque microenvironment.

ANGPTL4 stabilizes atherosclerotic plaques and modulates the phenotypic transition of vascular smooth muscle cells through KLF4 downregulation

Atherosclerosis, the leading cause of death, is a vascular disease of chronic inflammation. We recently showed that angiopoietin-like 4 (ANGPTL4) promotes cardiac repair by suppressing pathological inflammation. Given the fundamental contribution of inflammation to atherosclerosis, we assessed the role of ANGPTL4 in the development of atherosclerosis and determined whether ANGPTL4 regulates atherosclerotic plaque stability. We injected ANGPTL4 protein twice a week into atherosclerotic Apoe-/- mice and analyzed the atherosclerotic lesion size, inflammation, and plaque stability. In atherosclerotic mice, ANGPTL4 reduced atherosclerotic plaque size and vascular inflammation. In the atherosclerotic lesions and fibrous caps, the number of α-SMA(+), SM22α(+), and SM-MHC(+) cells was higher, while the number of CD68(+) and Mac2(+) cells was lower in the ANGPTL4 group. Most importantly, the fibrous cap was significantly thicker in the ANGPTL4 group than in the control group. Smooth muscle cells (SMCs) isolated from atherosclerotic aortas showed significantly increased expression of CD68 and Krüppel-like factor 4 (KLF4), a modulator of the vascular SMC phenotype, along with downregulation of α-SMA, and these changes were attenuated by ANGPTL4 treatment. Furthermore, ANGPTL4 reduced TNFα-induced NADPH oxidase 1 (NOX1), a major source of reactive oxygen species, resulting in the attenuation of KLF4-mediated SMC phenotypic changes. We showed that acute myocardial infarction (AMI) patients with higher levels of ANGPTL4 had fewer vascular events than AMI patients with lower levels of ANGPTL4 (p < 0.05). Our results reveal that ANGPTL4 treatment inhibits atherogenesis and suggest that targeting vascular stability and inflammation may serve as a novel therapeutic strategy to prevent and treat atherosclerosis. Even more importantly, ANGPTL4 treatment inhibited the phenotypic changes of SMCs into macrophage-like cells by downregulating NOX1 activation of KLF4, leading to the formation of more stable plaques.

Cardioprotective potential of lithium and role of fractalkine in euthymic patients with bipolar disorder

OBJECTIVE

Over a half century, lithium has been used as the first-line medication to treat bipolar disorder. Emerging clinical and laboratory studies suggest that lithium may exhibit cardioprotective effects in addition to neuroprotective actions. Fractalkine (CX3CL1) is a unique chemokine associated with the pathogenesis of mood disorders and cardiovascular diseases. Herein we aimed to ascertain whether lithium treatment is associated with favorable cardiac structure and function in relation to the reduced CX3CL1 among patients with bipolar disorder.

METHODS

We recruited 100 euthymic patients with bipolar I disorder aged over 20 years to undergo echocardiographic study and measurement of plasma CX3CL1. Associations between lithium treatment, cardiac structure and function and peripheral CX3CL1 were analyzed according to the cardiovascular risk. The high cardiovascular risk was defined as (1) age ⩾ 45 years in men or ⩾ 55 years in women or (2) presence of concurrent cardiometabolic diseases.

RESULTS

In the high cardiovascular risk group (n = 61), patients who received lithium as the maintenance treatment had significantly lower mean values of left ventricular internal diameters at end-diastole (Cohen's d = 0.65, p = 0.001) and end-systole (Cohen's d = 0.60, p = 0.004), higher mean values of mitral valve E/A ratio (Cohen's d = 0.51, p = 0.019) and superior performance of global longitudinal strain (Cohen's d = 0.51, p = 0.037) than those without lithium treatment. In addition, mean plasma levels of CX3CL1 in the high cardiovascular risk group were significantly lower among patients with lithium therapy compared with those without lithium treatment (p = 0.029). Multiple regression models showed that the association between lithium treatment and mitral value E/A ratio was contributed by CX3CL1.

CONCLUSION

Data from this largest sample size study of the association between lithium treatment and echocardiographic measures suggest that lithium may protect cardiac structure and function in patients with bipolar disorder. Reduction of CX3CL1 may mediate the cardioprotective effects of lithium.

Kawasaki Disease-like Vasculitis Facilitates Atherosclerosis, and Statin Shows a Significant Antiatherosclerosis and Anti-Inflammatory Effect in a Kawasaki Disease Model Mouse

Kawasaki disease (KD) is an acute form of systemic vasculitis that may promote atherosclerosis in adulthood. This study examined the relationships between KD, atherosclerosis, and the long-term effects of HMG-CoA inhibitors (statins). Candida albicans water-soluble fraction (CAWS) was injected intraperitoneally into 5-week-old male apolipoprotein-E-deficient (Apo E-/-) mice to create KD-like vasculitis. Mice were divided into 4 groups: the control, CAWS, CAWS+statin, and late-statin groups. They were sacrificed at 6 or 10 weeks after injection. Statin was started after CAWS injection in all groups except the late-statin group, which was administered statin internally 6 weeks after injection. Lipid plaque lesions on the aorta were evaluated with Oil Red O. The aortic root and abdominal aorta were evaluated with hematoxylin and eosin staining and immunostaining. CAWS vasculitis significantly enhanced aortic atherosclerosis and inflammatory cell invasion into the aortic root and abdominal aorta. Statins significantly inhibited atherosclerosis and inflammatory cell invasion, including macrophages. CAWS vasculitis, a KD-like vasculitis, promoted atherosclerosis in Apo E-/- mice. The long-term oral administration of statin significantly suppressed not only atherosclerosis but also inflammatory cell infiltration. Therefore, statin treatment may be used for the secondary prevention of cardiovascular events during the chronic phase of KD.

Highly Bright AIE Nanoparticles by Regulating the Substituent of Rhodanine for Precise Early Detection of Atherosclerosis and Drug Screening

Fluorescent probes capable of precise detection of atherosclerosis (AS) at an early stage and fast assessment of anti-AS drugs in animal level are particularly valuable. Herein, a highly bright aggregation-induced emission (AIE) nanoprobe is introduced by regulating the substituent of rhodanine for early detection of atherosclerotic plaque and screening of anti-AS drugs in a precise, sensitive, and rapid manner. With dicyanomethylene-substituted rhodanine as the electron-withdrawing unit, the AIE luminogen named TPE-T-RCN shows the highest molar extinction coefficient, the largest photoluminescence quantum yield, and the most redshifted absorption/emission spectra simultaneously as compared to the control compounds. The nanoprobes are obtained with an amphiphilic copolymer as the matrix encapsulating TPE-T-RCN molecules, which are further surface functionalized with anti-CD47 antibody for specifically binding to CD47 overexpressed in AS plaques. Such nanoprobes allow efficient recognition of AS plaques at different stages in apolipoprotein E-deficient (apoE^-/- ) mice, especially for the recognition of early-stage AS plaques prior to micro-computed tomography (CT) and magnetic resonance imaging (MRI). These features impel to apply the nanoprobes in monitoring the therapeutic effects of anti-AS drugs, providing a powerful tool for anti-AS drug screening. Their potential use in targeted imaging of human carotid plaque is further demonstrated.

Simvastatin therapy attenuates memory deficits that associate with brain monocyte infiltration in chronic hypercholesterolemia

Evidence associates cardiovascular risk factors with unfavorable systemic and neuro-inflammation and cognitive decline in the elderly. Cardiovascular therapeutics (e.g., statins and anti-hypertensives) possess immune-modulatory functions in parallel to their cholesterol- or blood pressure (BP)-lowering properties. How their ability to modify immune responses affects cognitive function is unknown. Here, we examined the effect of chronic hypercholesterolemia on inflammation and memory function in Apolipoprotein E (ApoE) knockout mice and normocholesterolemic wild-type mice. Chronic hypercholesterolemia that was accompanied by moderate blood pressure elevations associated with apparent immune system activation characterized by increases in circulating pro-inflammatory Ly6Chi monocytes in ApoE^-/- mice. The persistent low-grade immune activation that is associated with chronic hypercholesterolemia facilitates the infiltration of pro-inflammatory Ly6Chi monocytes into the brain of aged ApoE^-/- but not wild-type mice, and links to memory dysfunction. Therapeutic cholesterol-lowering through simvastatin reduced systemic and neuro-inflammation, and the occurrence of memory deficits in aged ApoE^-/- mice with chronic hypercholesterolemia. BP-lowering therapy alone (i.e., hydralazine) attenuated some neuro-inflammatory signatures but not the occurrence of memory deficits. Our study suggests a link between chronic hypercholesterolemia, myeloid cell activation and neuro-inflammation with memory impairment and encourages cholesterol-lowering therapy as safe strategy to control hypercholesterolemia-associated memory decline during ageing.

Analysis of MicroRNAs Associated With Carotid Atherosclerotic Plaque Rupture With Thrombosis

Atherosclerosis is a progressive vascular wall inflammatory disease, and the rupture of atherosclerotic vulnerable plaques is the leading cause of morbidity and mortality worldwide. This study intended to explore the potential mechanisms behind plaque rupture and thrombosis in ApoE knockout mice. The spontaneous plaque rupture models were established, and left carotid artery tissues at different time points (1-, 2-, 4-, 6-, 8-, 12-, and 16-week post-surgery) were collected. By the extent of plaque rupture, plaque was defined as (1) control groups, (2) atherosclerotic plaque group, and (3) plaque rupture group. Macrophage (CD68), MMP-8, and MMP-13 activities were measured by immunofluorescence. Cytokines and inflammatory markers were measured by ELISA. The left carotid artery sample tissue was collected to evaluate the miRNAs expression level by miRNA-microarray. Bioinformatic analyses were conducted at three levels: (2) vs. (1), (3) vs. (2), and again in seven time series analysis. The plaque rupture with thrombus and intraplaque hemorrhage results peaked at 8 weeks and decreased thereafter. Similar trends were seen in the number of plaque macrophages and lipids, the expression of matrix metalloproteinase, and the atherosclerotic and plasma cytokine levels. MiRNA-microarray showed that miR-322-5p and miR-206-3p were specifically upregulated in the atherosclerotic plaque group compared with those in the control group. Meanwhile, miR-466h-5p was specifically upregulated in the plaque rupture group compared with the atherosclerotic plaque group. The highest incidence of plaque rupture and thrombosis occurred at 8 weeks post-surgery. miR-322-5p and miR-206-3p may be associated with the formation of atherosclerotic plaques. miR-466h-5p may promote atherosclerotic plaque rupture via apoptosis-related pathways.

Atorvastatin pleiotropically decreases intraplaque angiogenesis and intraplaque haemorrhage by inhibiting ANGPT2 release and VE-Cadherin internalization

OBJECTIVE

Statins pleiotropically provide additional benefits in reducing atherosclerosis, but their effects on intraplaque angiogenesis (IPA) and hemorrhage (IPH) remain unclear. Therefore, we discriminated statin's lipid-lowering dependent and independent effects on IPA and IPH.

APPROACH AND RESULTS

ApoE3*Leiden mice are statin-responsive due to ApoE and LDLR presence, but also allow to titrate plasma cholesterol levels by diet. Therefore, ApoE3*Leiden mice were fed a high-cholesterol-inducing-diet (HCD) with or without atorvastatin (A) or a moderate-cholesterol-inducing-diet (MCD). Mice underwent vein graft surgery to induce lesions with IPA and IPH. Cholesterol levels were significantly reduced in MCD (56%) and HCD + A (39%) compared to HCD with no significant differences between MCD and HCD + A. Both MCD and HCD + A have a similar reduction in vessel remodeling and inflammation comparing to HCD. IPA was significantly decreased by 30% in HCD + A compared to HCD or MCD. Atorvastatin treatment reduced the presence of immature vessels by 34% vs. HCD and by 25% vs. MCD, resulting in a significant reduction of IPH. Atorvastatin's anti-angiogenic capacity was further illustrated by a dose-dependent reduction of ECs proliferation and migration. Cultured mouse aortic-segments lost sprouting capacity upon atorvastatin treatment and became 30% richer in VE-Cadherin expression and pericyte coverage. Moreover, Atorvastatin inhibited ANGPT2 release and decreased VE-Cadherin(Y685)-phosphorylation in ECs.

CONCLUSIONS

Atorvastatin has beneficial effects on vessel remodeling due to its lipid-lowering capacity. Atorvastatin has strong pleiotropic effects on IPA by decreasing the number of neovessels and on IPH by increasing vessel maturation. Atorvastatin improves vessel maturation by inhibiting ANGPT2 release and phospho(Y658)-mediated VE-Cadherin internalization.

Inhibition of macrophage proliferation dominates plaque regression in response to cholesterol lowering

Statins induce plaque regression characterized by reduced macrophage content in humans, but the underlying mechanisms remain speculative. Studying the translational APOE*3-Leiden.CETP mouse model with a humanized lipoprotein metabolism, we find that systemic cholesterol lowering by oral atorvastatin or dietary restriction inhibits monocyte infiltration, and reverses macrophage accumulation in atherosclerotic plaques. Contrary to current believes, none of (1) reduced monocyte influx (studied by cell fate mapping in thorax-shielded irradiation bone marrow chimeras), (2) enhanced macrophage egress (studied by fluorescent bead labeling and transfer), or (3) atorvastatin accumulation in murine or human plaque (assessed by mass spectrometry) could adequately account for the observed loss in macrophage content in plaques that undergo phenotypic regression. Instead, suppression of local proliferation of macrophages dominates phenotypic plaque regression in response to cholesterol lowering: the lower the levels of serum LDL-cholesterol and lipid contents in murine aortic and human carotid artery plaques, the lower the rates of in situ macrophage proliferation. Our study identifies macrophage proliferation as the predominant turnover determinant and an attractive target for inducing plaque regression.

Plasma APE1/Ref-1 Correlates with Atherosclerotic Inflammation in ApoE-/- Mice

Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/Ref-1) is involved in DNA base repair and reducing activity. However, the role of APE1/Ref-1 in atherosclerosis is unclear. Herein, we investigated the role of APE1/Ref-1 in atherosclerotic apolipoprotein E (ApoE^−/−) mice fed with a Western-type diet. We found that serologic APE1/Ref-1 was strongly correlated with vascular inflammation in these mice. Neutrophil/lymphocyte ratio (NLR), endothelial cell/macrophage activation, and atherosclerotic plaque formation, reflected by atherosclerotic inflammation, were increased in the ApoE^−/− mice fed with a Western-type diet. APE1/Ref-1 expression was upregulated in aortic tissues of these mice, and was co-localized with cells positive for cluster of differentiation 31 (CD31) and galectin-3, suggesting endothelial cell/macrophage expression of APE1/Ref-1. Interestingly, APE1/Ref-1 plasma levels of ApoE^−/− mice fed with a Western-type diet were significantly increased compared with those of the mice fed with normal diet (15.76 ± 3.19 ng/mL vs. 3.51 ± 0.50 ng/mL, p < 0.05), and were suppressed by atorvastatin administration. Correlation analysis showed high correlation between plasma APE1/Ref-1 levels and NLR, a marker of systemic inflammation. The cut-off value for APE1/Ref-1 for predicting atherosclerotic inflammation at 4.903 ng/mL showed sensitivity of 100% and specificity of 91%. We conclude that APE1/Ref-1 expression is upregulated in aortic endothelial cells/macrophages of atherosclerotic mice, and that plasma APE1/Ref-1 levels could predict atherosclerotic inflammation.

Intensive Statin Therapy Compromises the Adiponectin-AdipoR Pathway in the Human Monocyte-Macrophage Lineage

Background and Purpose—

Statins are widely used for cardiovascular disease prevention through cholesterol-lowering and anti-inflammatory effects. Adiponectin, an anti-inflammatory adipokine, acts via two receptors, AdipoR1 and AdipoR2, to exert atheroprotective effects on the vasculature. We investigated whether statins can modulate the adiponectin-AdipoR pathway in the human monocyte-macrophage lineage.

Methods—

Monocytes were isolated from the whole blood of patients with severe carotid atherosclerosis (cross-sectional study) or from patients with cardiovascular risk factors (longitudinal study) and assessed for AdipoR1 and AdipoR2 gene expression using quantitative real-time polymerase chain reaction. In vitro, THP-1 (Tamm-Horsfall protein 1) macrophages were treated with increasing atorvastatin or rosuvastatin doses for 24- or 72-hours to determine the effect of statins on AdipoR expression and activity. Macrophage cytokine secretion (IL [interleukin]-1β, IL-10, IL-6, and TNF [tumor necrosis factor]-α) was assessed by electrochemiluminescence.

Results—

AdipoR1 and AdipoR2 mRNA expression on circulating monocytes from patients with carotid atherosclerosis, was significantly lower by 1.36- and 1.17-fold, respectively, in statin users versus statin-naïve patients. Specifically, patients on high doses of atorvastatin (40–80 mg) or rosuvastatin (20–40 mg) had significantly lower AdipoR gene expression versus statin-naïve patients. Similarly, in the longitudinal in vivo study, longer atorvastatin/rosuvastatin treatment (≥5 months) in patients with cardiovascular risk factors resulted in lower AdipoR gene expression on circulating monocytes versus prestatin levels. In vitro, higher statin doses and longer exposure resulted in a greater decrease in AdipoR mRNA expression and greater macrophage secretion of pro-inflammatory cytokines, IL-1β, IL-6, and TNF-α. High statin doses also reduced adiponectin’s capacity to suppress intracellular cholesteryl ester levels in oxLDL (oxidized LDL)-loaded macrophages, with rosuvastatin exhibiting higher potency than atorvastatin.

Conclusions—

Our in vivo and in vitro studies identified a novel pleiotropic property of statins in modulating the adiponectin-AdipoR pathway in the human monocyte-macrophage lineage, where intensive statin therapy compromised the expression and function of adiponectin and its receptors.

Oligomeric proanthocyanidins and epigallocatechin gallate aggravate autophagy of foam cells through the activation of Class III PI3K/Beclin1-complex mediated cholesterol efflux

Foam cells are specialized types of cells which predominate the necrotic core of atherosclerotic plaque. Recently, autophagy-mediated cholesterol efflux from foam cells has been proposed as a beneficial therapy for atherosclerosis. The purpose of this study was to delineate the underlying molecular mechanism of oligomeric proanthocyanidins (OPC) and epigallocatechin gallate (EGCG) induced autophagy of foam cells and associated cholesterol efflux. The oxidized low-density lipoprotein induced foam cells demonstrated impaired autophagy flux through the downregulated expressions of LC3BII/LC3BI, autophagy related gene-5, Class III phosphoinositide 3 kinase (Class III PI3K), Beclin1, ABCA1, and ABCG1 with concomitant increase in the expressions of protein 62, Class I phosphoinositide 3 kinase, Akt, and mammalian target of rapamycin. However, these effects were significantly abolished by treatment with OPC and EGCG through activation of autophagy flux via Class III PI3K/Beclin1 and with upregulated expression of transporter proteins ABCA1 and ABCG1. Furthermore, the cholesterol efflux process in the foam cells was activated by lysosomal acid lipase and cathepsin D facilitated lipolysis of lipid droplets. Taken together, our data demonstrate that OPC and EGCG treatment stimulated the coordinated activation of autophagy and cholesterol efflux through Class III PI3K/Beclin1 pathway in foam cells, suggesting a promising therapeutic strategy against atherosclerosis.

Vulnerable Plaque, Characteristics, Detection, and Potential Therapies

Plaque development and rupture are hallmarks of atherosclerotic vascular disease. Despite current therapeutic developments, there is an unmet necessity in the prevention of atherosclerotic vascular disease. It remains a challenge to determine at an early stage if atherosclerotic plaque will become unstable and vulnerable. The arrival of molecular imaging is receiving more attention, considering it allows for a better understanding of the biology of human plaque and vulnerabilities. Various plaque therapies with common goals have been tested in high-risk patients with cardiovascular disease. In this work, the process of plaque instability, along with current technologies for sensing and predicting high-risk plaques, is debated. Updates on potential novel therapeutic approaches are also summarized.

Sulindac-derived retinoid X receptor-α modulator attenuates atherosclerotic plaque progression and destabilization in ApoE-/- mice

BACKGROUND AND PURPOSE

Atherosclerosis is a chronic inflammatory disease, and retinoid X receptor-α (RXRα) is an intriguing anti-atherosclerosis target. This study investigated whether and how an RXRα modulator, K-80003, derived from a non-steroidal anti-inflammatory drug attenuates atherosclerotic plaque progression and destabilization.

EXPERIMENTAL APPROACH

Our previously established ApoE-/- mouse model of carotid vulnerable plaque progression was treated with K-80003 or vehicle for 4 or 8 weeks. Samples of carotid arteries and serum were collected to determine atherosclerotic lesion size, histological features, expression of related proteins, and lipid profiles. In vitro studies were carried out in 7-ketocholesterol (7-KC)-stimulated macrophages treated with or without K-80003.

KEY RESULTS

K-80003 significantly reduced lesion size, plaque rupture, macrophage infiltration, and inflammatory cytokine levels. Plaque macrophages positive for nuclear p65 (RelA) NF-κB subunit were markedly reduced after K-80003 treatment. Also, K-80003 treatment inhibited 7-KC-induced p65 nuclear translocation, IκBα degradation, and transcription of NF-κB target genes. In addition, K-80003 inhibited NF-κB pathway mainly through the reduction of p62/sequestosome 1 (SQSTM1), probably due to promotion of autophagic flux by K-80003. Mechanistically, cytoplasmic localization of RXRα was associated with decreased autophagic flux. Increasing cytoplasmic RXRα expression by overexpression of RXRα/385 mutant decreased autophagic flux in RAW264.7 cells. Finally, K-80003 strongly inhibited 7-KC-induced RXRα cytoplasmic translocation.

CONCLUSIONS AND IMPLICATIONS

K-80003 suppressed atherosclerotic plaque progression and destabilization by promoting macrophage autophagic flux and consequently inhibited the p62/SQSTM1-mediated NF-κB proinflammatory pathway. Thus, targeting RXRα-mediated autophagy-inflammation axis by its noncanonical modulator may represent a promising strategy to treat atherosclerosis.

Ginkgo Biloba Leaf Extract Attenuates Atherosclerosis in Streptozotocin-Induced Diabetic ApoE-/- Mice by Inhibiting Endoplasmic Reticulum Stress via Restoration of Autophagy through the mTOR Signaling Pathway

Background

There is a crosstalk between endoplasmic reticulum stress (ERS) and autophagy, and autophagy could attenuate endoplasmic reticulum stress-mediated apoptosis. Ginkgo biloba leaf extract (GBE) exerts vascular protection functions. The purpose of the present study is to investigate the role of autophagy in diabetic atherosclerosis (AS) and the effect of GBE on autophagy and ERS.

Methods

Network pharmacology was utilized to predict the targets and pathways of the active chemical compounds of Gingko biloba leaf to attenuate AS. ApoE^−/− mice were rendered diabetic by intraperitoneal ingestion with streptozotocin combined with a high-fat diet. The diabetic mice were divided into five groups: model group, atorvastatin group, rapamycin group, and low- and high-dose GBE groups. Serum and tissue markers of autophagy or ERS markers, including the protein expression, were examined.

Results

The mammalian target of rapamycin (mTOR) and NF-κB signaling pathways were targeted by the active chemical compounds of GBE to attenuate AS predicted by network pharmacology. GBE reduced the plaque area/lumen area and the plaque lipid deposition area/intimal area and inhibited the expressions of CD68, MMP2, and MMP9. Rapamycin and GBE inhibited the expression of mTOR and SQSTM1/p62 which increased in the aorta of diabetic mice. In addition, GBE reduced the expression of ERS markers in diabetic mice. GBE reduced the serum lipid metabolism levels, blood glucose, and inflammatory cytokines.

Conclusion

Impaired autophagy and overactive endoplasmic reticulum stress contributed to diabetic atherosclerosis. mTOR inhibitor rapamycin and GBE attenuated diabetic atherosclerosis by inhibiting ERS via restoration of autophagy through inhibition of mTOR.

Randomized Controlled Trial of Pulpotomy in Primary Molars using MTA and Formocresol Compared to 3Mixtatin: A Novel Biomaterial

OBJECTIVE

This study was conducted to compare the efficacy of 3Mixtatin (a combination of simvastatin and 3Mix antibiotic) with MTA and Formocresol for the pulpotomy of primary molars.

STUDY DESIGN

114 children aged 3-6 years old with 150 primary molars were randomly allocated to three groups. MTA, Formocresol or 3Mixtatin were used for Pulpotomies. Hard setting zinc oxide eugenol was used to cover these materials. The teeth were restored with amalgam. Blinded radiographic and clinical examinations were conducted at 6, 12 and 24 months after treatment for the presence of pain, tenderness to palpation and percussion, sinus tract, swelling, presence of internal or external root resorption, inter-radicular radiolucency, and periapical lesion.

RESULTS

122 teeth were available for 24-month follow-up study. The overall success rate was 78.9% for FC, 90.5% for 3Mixtatin and 88.1% for MTA group. There was no significant difference in overall success rate among the groups after 24-month follow-up (X²=2.43, df = 2, P =0.27).

CONCLUSION

Our findings demonstrated remarkable results of 3Mixtatin in pulpotomy of primary teeth at the 24-month follow-up. Therefore, 3Mixtatin may be considered as an effective material in pulpotomy of primary teeth because of its successful results.

Synergistic Effect of Atorvastatin and Folic Acid on Cardiac Function and Ventricular Remodeling in Chronic Heart Failure Patients with Hyperhomocysteinemia

BACKGROUND At present, a constant progress in pathophysiology understanding and treatment of the chronic heart failure (CHF) is arising. Meanwhile, hyperhomocysteinemia (HHcy) has been linked to impaired left ventricular function and clinical class in patients with CHF. Atorvastatin therapy can reduce the incidence of sudden cardiac death in patients with advanced CHF. Folic acid could enhance endothelial function in vascular disease states. The present study aims to investigate the effect of atorvastatin and folic acid combined on the cardiac function and ventricular remodeling in CHF patients with HHcy. MATERIAL AND METHODS Elderly CHF patients with HHcy were divided into four groups: routine, routine + atorvastatin, routine + folic acid, and routine + atorvastatin + folic acid groups. Serum homocysteine (Hcy) level was detected using enzymatic cycling methods, and N-terminal pro brain natriuretic peptide (NT-proBNP) level by ELISA. The cardiac function indexes and left ventricular early diastolic peak flow velocity/atrial systolic peak flow velocity (E/A) ratio were evaluated. The six-minute walk test was performed to measure the six-minute walk distance (6MWD). RESULTS 6MWD increased, the serum Hcy and NT-proBNP levels decreased, and cardiac function was improved compared with before treatment, which was the most significant in the routine + atorvastatin + folic acid group, followed by the routine + atorvastatin group, then the routine + folic acid group, and lastly, the routine group. CONCLUSIONS The results indicated that the combination of atorvastatin and folic acid improved the cardiac function and inhibited ventricular remodeling of elderly CHF patients with HHcy.

Atorvastatin Inhibits Inflammatory Response, Attenuates Lipid Deposition, and Improves the Stability of Vulnerable Atherosclerotic Plaques by Modulating Autophagy

Atherosclerosis is a chronic disease comprising intima malfunction and arterial inflammation. Recent studies have demonstrated that autophagy could inhibit inflammatory response in atherosclerosis and exert subsequent atheroprotective effects. Our previous study also demonstrated the role of autophagy in the inhibition of inflammation by atorvastatin in vitro. Therefore, in the present study, we aimed to determine whether atorvastatin could upregulate autophagy to inhibit inflammatory cytokines secretion, lipid accumulation, and improve vulnerable plaque stability, both in vitro and in vivo. First, we established a vulnerable atherosclerotic plaque mouse model through partial ligation of left common carotid artery and left renal artery to explore the effect of atorvastatin on vulnerable plaques. The results showed that atorvastatin could enhance the stability of vulnerable atherosclerotic plaques and reduce the lesion area in the aorta. Atorvastatin could also inhibit NLRP3 inflammasome activation and inflammatory cytokines, such as IL-1β, TNF-α, and IL-18 secretion in vivo. Atorvastatin treatment upregulated the expression of autophagy-related protein microtubule-associated protein light chain (LC3B) and downregulated the expression of SQSTM1/p62, which suggested that autophagy was activated in vulnerable plaques. Transmission electron microscopy further demonstrated the atorvastatin-induced increase in autophagy activity in vulnerable atherosclerotic plaques. We employed oxidized low-density lipoprotein (ox-LDL) to stimulate RAW264.7 cells with atorvastatin, which showed that atorvastatin could attenuate lipid deposition, ameliorate inflammation, inhibit NLRP3 inflammasome activation, and enhance autophagy in vitro. All these beneficial effects were abolished by 3-methyladenine treatment, an autophagy inhibitor. Atorvastatin also significantly inhibited the phosphorylation of mTOR, which strongly suggested the involvement of the mTOR pathway. Our study proposed a new role for atorvastatin as an autophagy inducer to exert anti-inflammatory and atheroprotective effects, to stabilize vulnerable atherosclerotic plaques.

Are the effects of drugs to prevent and to treat heart failure always concordant? The statin paradox and its implications for understanding the actions of antidiabetic medications

Most treatments for chronic heart failure are effective both in preventing its onset and reducing its progression. However, statins prevent the development of heart failure, but they do not decrease morbidity and mortality in those with established heart failure. This apparent discordance cannot be explained by an effect to prevent interval myocardial infarctions. Instead, it seems that the disease that statins were preventing in trials of patients with a metabolic disorder was different from the disease that they were treating in trials of chronic heart failure. The most common phenotype of heart failure in patients with obesity and diabetes is heart failure with a preserved ejection fraction (HFpEF). In this disorder, the anti-inflammatory effects of statins might ameliorate myocardial fibrosis and cardiac filling abnormalities, but these actions may have little relevance to patients with heart failure and a reduced ejection fraction (HFrEF), whose primary derangement is cardiomyocyte loss and stretch. These distinctions may explain why statins were ineffective in trials that focused on HFrEF, but have been reported to produce favourable effects in observational studies of HFpEF. Similarly, selective cytokine antagonists were ineffective in HFrEF, but have been associated with benefits in HFpEF. These observations may have important implications for our understanding of the effects of antihyperglycaemic medications. Glucagon-like peptide-1 receptor agonists have had neutral effects on heart failure events in people at risk for HFpEF, but have exerted deleterious actions in HFrEF. Similarly, sodium-glucose co-transporter 2 inhibitors, which exert anti-inflammatory effects and reduce heart failure events in patients who are prone to HFpEF, may not be effective in HFrEF. The distinctions between HFrEF and HFpEF may explain why the effects of drugs on heart failure events in diabetes trials may not be relevant to their use in patients with systolic dysfunction.

Xuezhikang, an extract from red yeast rice, attenuates vulnerable plaque progression by suppressing endoplasmic reticulum stress-mediated apoptosis and inflammation

Xuezhikang (XZK), an extract of red yeast rice, is a traditional Chinese medicine widely used for the treatment of cardiovascular diseases in China and other countries. However, whether XZK treatment can improve atherosclerotic plaque stability is not fully understood. Based on our previously developed mouse model of spontaneous vulnerable plaque formation and rupture in carotid arteries in ApoE^-/- mice. We showed that low-dose (600 mg/kg/d) XZK improved plaque stability without decreasing plaque area, whereas high-dose (1200 mg/kg/d) XZK dramatically inhibited vulnerable plaque progression accompanied by decreased plaque area. Mechanistically, XZK significantly suppressed lesional endoplasmic reticulum (ER) stress in mouse carotid arteries. In vitro, XZK inhibited 7-KC-induced activation of ER stress in RAW264.7 macrophages, as assessed by the reduced levels of p-PERK, p-IRE1α, p-eIF2α, c-ATF6, s-XBP1, and CHOP. Compared to controls, the XZK-treated group displayed dramatically decreased apoptotic cell numbers (shown by decreased TUNEL- and cleaved caspase3-positive cells), lower necrotic core area and ratio, and reduced expression of NF-κB target gene. In RAW264.7 cells, XZK inhibited 7-KC-induced upregulation of apoptosis, protein expression of apoptotic markers (cleaved caspase-3 and cleaved PARP), and NF-κB activation (shown by target gene transcription and IκBα reduction). Collectively, our results suggest that XZK effectively suppresses vulnerable plaque progression and rupture by mitigating macrophage ER stress and consequently inhibiting apoptosis and the NF-κB pro-inflammatory pathway, thereby providing an alternative therapeutic strategy for stabilizing atherosclerotic plaques.

Does short preoperative statin therapy prevent infectious complications in adults undergoing cardiac or non-cardiac surgery? A meta-analysis of 5 randomized placebo-controlled trials

Objectives:

To evaluate the effect of preoperative statin therapy on the incidence of postoperative infection.

Methods:

This systematic review of the literature was carried out in August 2015. Studies were retrieved via PubMed, Embase, and the Cochrane Library (1980 to 2015), and the reference files were limited to English-language articles. We used a standardized protocol, and a meta-analysis was performed for data abstraction.

Results:

Five studies comprising 1,362 patients qualified for the analysis. The incidence of postoperative infections in the statin group (1.1%) was not significantly lower than that in the placebo group (2.4%), with a risk ratio (RR) of 0.56 (95% confidence interval [CI] 0.24-1.33, p=0.19). Patients of 3 studies underwent cardiac surgery. The aggregated results of these studies failed to show significant differences in postoperative infection when a fixed effects model was used (RR: 0.39; 95% CI: 0.08-1.97, p=0.26].

Conclusions:

We failed to find sufficient evidence to support the association between statin use and postoperative infectious complications. The absence of any evidence for a beneficial effect in available randomized trials reduces the likelihood of a causal effect as reported in observational studies.

99mTc-labeled bevacizumab for detecting atherosclerotic plaque linked to plaque neovascularization and monitoring antiangiogenic effects of atorvastatin treatment in ApoE-/- mice

Atherosclerotic neovascularization plays a significant role in plaque instability as it provides additional lipids and inflammatory mediators to lesions, and resulting in intraplaque hemorrhage. Vascular endothelial growth factor-A (VEGF-A) is considered the predominant proangiogenic factor in angiogenesis. Bevacizumab, a humanized monoclonal antibody, specifically binds to all VEGF-A isoforms with high affinity. Therefore, in this study, we designed ^99mTc-MAG₃-bevacizumab as a probe, and then investigated its usefulness as a new imaging agent for the detection of plaque neovessels, while also assessing the therapeutic effect of atorvastatin treatment. The ApoE^−/− mice treated with atorvastatin were used as the treatment group, and C57BL/6 J mice were selected as the control group. ^99mTc-MAG₃-bevacizumab uptake was visualized on atherosclerotic lesions by non-invasive in-vivo micro-SPECT/CT and ex-vivo BSGI planar imaging. The value of P/B in each part of the aorta of ApoE^−/− mice was higher than in the treatment group and the C57BL/6 J mice, which was confirmed by Oil Red O staining, CD31 staining and VEGF immunohistochemistry staining. ^99mTc-MAG₃-bevacizumab imaging allowed for the non-invasive diagnosis and assessment of plaque neovascularization. Furthermore, this probe may be used as a new molecular imaging agent to assess the antiangiogenic effect of atorvastatin.

Inhibition of Angiotensin II-Induced Cardiac Fibrosis by Atorvastatin in Adiponectin Knockout Mice

Adiponectin is a polypeptide known to inhibit cardiac fibrosis via the activation of ‎adenosine monophosphate-activated protein kinase (AMPK). Statins can also activate AMPK, resulting in the secretion of adiponectin. We determined whether atorvastatin inhibits angiotensin II-induced cardiac fibrosis (AICF) in the presence or absence of adiponectin. Adiponectin knockout (APN-KO, n = 44) and wild type (WT, n = 44) mice were received subcutaneous angiotensin II (1.5 mg/kg/day), and atorvastatin (10 mg/kg/day) was administered orally for 15 days. The mRNA expression levels of collagen type I and III, as well as AMPK phosphorylation levels in cardiac tissue were then measured. In the APN-KO mice, collagen type I (p < 0.001) and type III (p = 0.001) expression was significantly greater when treated with angiotensin II, while their expression was significantly reduced in the presence of angiotensin II and atorvastatin. Relative AMPK phosphorylation levels in APN-KO mice were also significantly higher in the angiotensin II + atorvastatin group when compared with angiotensin II group alone. We conclude that atorvastatin attenuates AICF independently from adiponectin by activating AMPK. These data suggest potential cardioprotection beyond lipid modulation potentially supporting statin pleiotropic hypothesis.

Preparation and characterisation of atorvastatin and curcumin-loaded chitosan nanoformulations for oral delivery in atherosclerosis

Atorvastatin known to be a potential inhibitor of HMG-CoA reductase involved in the synthesis of cholesterol. It is touted as miracle drug due to its profound effect in decreasing the low-density lipoproteins in blood. Unfortunately, the high dosage used poses side-effects relatively in comparison to other statins. On the other hand, curcumin has a diverse therapeutic potential in health and disease. However, the poor aqueous solubility and low bioavailability hinders the therapeutic potential of it when administrated orally. Therefore, it was thought to minimise the frequency of atorvastatin doses to avoid the possibility of drug resistance and also to overcome the limitations of curcumin for desirable therapeutic effects by using nanocarriers in drug delivery. In this investigation, synergistic effect of atorvastatin and curcumin nanocarriers was encapsulated by chitosan polymer. The chitosan nanocarriers prepared by ionic gelation method were characterised for their particle size, zeta potential, and other parameters. The drug-loaded nanocarriers exhibited good encapsulation efficiency (74.25%) and showed a slow and sustained release of atorvastatin and curcumin 60.36 and 61.44%, respectively, in a span of 48 h. The drug-loaded nanocarriers found to be haemocompatible and qualified for drug delivery in atherosclerosis.

Atorvastatin attenuates p‑cresyl sulfate‑induced atherogenesis and plaque instability in ApoE knockout mice

p-cresyl sulfate (PCS) is a protein-bound uremic toxin retained in the blood of patients with chronic kidney disease (CKD) As atherosclerosis is a primary cardiovascular complication for patients with CKD, the aim of the present study was to investigate the mechanisms underlying the aggravation of atherosclerosis by PCS. In addition, the effect of atorvastatin was assessed in reversing the effects of PCS. PCS was revealed to promote the initiation and progression of atherosclerosis. Following treatment with atorvastatin, apolipoprotein E knockout mice demonstrated a reduction in PCS-induced atherogenesis and plaque vulnerability. In addition, atorvastatin decreased the protein expression levels of vascular cell adhesion molecule-1 and intercellular cell adhesion molecule-1, and the interaction between leukocytes and endothelia. The plasma lipid profiles of mice were not significantly affected by gavage of low-dose atorvastatin. The results of the present study indicate that PCS promotes plaque growth and instability by enhancing leukocyte-endothelium interaction, and that these effects may be attenuated by atorvastatin treatment.

A randomized trial of direct pulp capping in primary molars using MTA compared to 3Mixtatin: a novel pulp capping biomaterial

OBJECTIVE

This study aimed to examine the efficacy of 3Mixtatin (a combination of simvastatin and 3Mix antibiotic) as a novel pulp capping biomaterial in DPC of human primary molars.

METHODS

In this randomized clinical trial, 160 primary molars from 83 healthy children aged 3-6 years were randomly allocated into four groups. Small traumatic non-caries pulpal exposures were treated by DPC using simvastatin, 3Mix, 3Mixtatin, or MTA. Capping materials were covered with hard-setting zinc oxide eugenol (ZOE) cement, and then, teeth were restored with amalgam. Clinical and radiographic examinations were conducted at 2, 6, and 12 months after treatment. The data were compared using chi-square test at a significance level of 0.05.

RESULTS

One hundred and twenty-nine teeth were available for follow-up study. By the end of 12 months, the overall success rates were 93.8% in MTA, 91.9% in 3Mixtatin, 62.5% in 3Mix, and 57.1% in simvastatingroups. No statistically significant difference was found between the outcomes of MTA and 3Mixtatin groups (P > 0.05). 3Mixtatin had statistically superior results compared to 3Mix and simvastatin (P < 0.01).

CONCLUSION

Radiographic and clinical outcomes in 3Mixtatin group could suggest it as an acceptable alternative in DPC of primary molar teeth.

Cytokines: roles in atherosclerosis disease progression and potential therapeutic targets

Atherosclerosis, the primary cause of cardiovascular disease (CVD), is a chronic inflammatory disorder in the walls of medium and large arteries. CVD is currently responsible for about one in three global deaths and this is expected to rise in the future due to an increase in the prevalence of obesity and diabetes. Current therapies for atherosclerosis mainly modulate lipid homeostasis and while successful at reducing the risk of a CVD-related death, they are associated with considerable residual risk and various side effects. There is, therefore, a need for alternative therapies aimed at regulating inflammation in order to reduce atherogenesis. This review will highlight the key role cytokines play during disease progression as well as potential therapeutic strategies to target them.

Preventive and therapeutic moderate aerobic exercise programs convert atherosclerotic plaques into a more stable phenotype

The mechanisms by which exercise affects atherosclerotic plaque stability remain incompletely understood. We evaluated the effects of two training protocols on both atherosclerotic plaque structure and the signaling pathways involved in plaque rupture.

METHODS

Male low-density lipoprotein (LDL) receptor knockout mice were fed a high-fat, high-cholesterol diet (HFD). One group was subjected to moderate exercise using a treadmill for 14weeks (preventive protocol). The other group started an exercise regimen after 16weeks of the HFD (therapeutic group). Atherosclerotic plaques within the aorta were evaluated for lipid and collagen contents, as well as for inflammatory markers. Plasma cholesterol and cytokine levels were also determined.

RESULTS

The mice receiving a HFD developed hypercholesterolemia and atherosclerotic plaques within the aorta. The aortas from the animals in the preventive protocol exhibited smaller lipid cores and higher collagen content. These animals also exhibited lower CD40 expression within the plaques. The aortas of the mice in the therapeutic group exhibited higher collagen content, but no differences in either lipid core size or plaque size were noted. No differences in blood pressure, plasma cholesterol, cytokine levels, plaque size or metalloproteinase 9 expression were observed in the trained animals compared with the sedentary animals.

CONCLUSION

Moderate aerobic exercise modified atherosclerotic plaque characteristics and converted the plaques into a more stable phenotype, increasing the collagen content in response to both exercise programs. Furthermore, moderate aerobic exercise reduced the animals' fat content and decreased the activity of the CD40-CD40L signaling pathway in the preventive group.

The Imaging Modulography Technique Revisited for High-Definition Intravascular Ultrasound: Theoretical Framework

Mechanical characterization of atherosclerotic lesions remains an essential step for the detection of vulnerable plaques (VPs). Recently, an intravascular ultrasound (IVUS) elasticity reconstruction method (iMOD) has been tested in vivo by our group. The major limitation of iMOD is the need to estimate the strain field in the entire VP despite attenuated depth penetration signals when using high-definition (HD) IVUS systems. Therefore, an extended iMOD approach (E-iMOD) was designed and applied to coronary lesions of patients imaged in vivo with IVUS. The E-iMOD method (i) quantified necrotic core areas with a mean absolute relative error of 3.5 ± 3.5% and (ii) identified Young's moduli of the necrotic cores and fibrous regions with mean values of 5.7 ± 0.8 kPa and 794.5 ± 22.0 kPa instead of 5 kPa and 800 kPa, respectively. This study demonstrates the potential of the improved HD-IVUS modulography technique E-iMOD to characterize coronary VPs.

Effect of Atorvastatin on Growth Differentiation Factor-15 in Patients with Type 2 Diabetes Mellitus and Dyslipidemia

BACKGROUND

Elevated serum levels of growth differentiation factor-15 (GDF-15) are associated with type 2 diabetes. Therefore, the effects of atorvastatin on metabolic parameters and GDF-15 levels in patients with type 2 diabetes and dyslipidemia were evaluated.

METHODS

In this prospective randomized trial from February 2013 to March 2014, 50 consecutive type 2 diabetic patients with a low density lipoprotein cholesterol (LDL-C) levels ≥100 mg/dL were enrolled. The patients were divided into two groups based on the amount of atorvastatin prescribed, 10 mg/day (n=23) or 40 mg/day (n=27). The effect of atorvastatin on metabolic parameters, including lipid profiles and GDF-15 levels, at baseline and after 8 weeks of treatment were compared.

RESULTS

The baseline metabolic parameters and GDF-15 levels were not significantly different between the two groups. After 8 weeks of treatment, the total cholesterol (TC) and LDL-C levels were significantly decreased in both groups. The mean changes in TC and LDL-C levels were more significant in the 40 mg atorvastatin group. The GDF-15 level was decreased in the 10 mg atorvastatin group, from 1,460.6±874.8 to 1,451.0±770.8 pg/mL, and was increased in the 40 mg atorvastatin group, from 1,271.6±801.0 to 1,341.4±855.2 pg/mL. However, the change in the GDF-15 level was not statistically significant in the 10 or 40 mg atorvastatin group (P=0.665 and P=0.745, respectively).

CONCLUSION

The GDF-15 levels were not significantly changed after an 8-week treatment with atorvastatin in type 2 diabetic patients.

Cholesterol-independent effects of atorvastatin prevent cardiovascular morbidity and mortality in a mouse model of atherosclerotic plaque rupture

Because cholesterol-independent effects of statins are difficult to determine in patients, we studied these pleiotropic effects in apolipoprotein E-deficient (ApoE(-/-)) mice with a mutation in the fibrillin-1 gene (Fbn1(C1039G+/-)). These mice develop exacerbated atherosclerosis and spontaneous plaque ruptures, accompanied by myocardial infarctions (MI) and sudden death. ApoE(-/-)Fbn1(C1039G+/-) mice were fed a Western diet (WD). At week 10 of WD, mice were divided in a control (WD), atorvastatin (10mg/kg/day + WD) and cholesterol withdrawal group (cholW, normal chow). The latter was included to compare the effects of atorvastatin with dietary lipid lowering. Fifteen weeks later, the mice were sacrificed. CholW, but not atorvastatin, reduced plasma cholesterol. Survival increased from 50% to 90% both in cholW and atorvastatin treated mice. CholW as well as atorvastatin treatment increased plaque collagen and fibrous cap thickness, but they did not affect the amount of plaque macrophages and T cells. MMP-2 and MMP-9 activity was significantly lower and the expression of MMP-12, TNF-α and IL-1β was strongly reduced in both treatment groups. Blood monocytes and neutrophils returned to baseline levels (ApoE(-/-) mice before the onset of atherosclerosis). Importantly, atorvastatin but not cholW significantly reduced coronary stenosis (from 50 to 28%) and the occurrence of MI (from 43 to 10%). In conclusion, independent of cholesterol lowering, atorvastatin significantly reduced mortality, plaque vulnerability and inflammation to the same extent as cholW. In addition, atorvastatin but not cholW reduced coronary stenosis and the occurrence of MI. These data unequivocally illustrate the significance of the pleiotropic effects of atorvastatin in the prevention of cardiovascular morbidity and mortality.

Protective effects of quercetin and taraxasterol against H2O2-induced human umbilical vein endothelial cell injury in vitro

Due to the association between inflammation and endothelial dysfunction in atherosclerosis, the blockage of the inflammatory process that occurs on the endothelial cells may be a useful way of preventing atherosclerosis. In the present study, human umbilical vein endothelial cells (HUVECs) were used to investigate the protective effects of quercetin and taraxasterol against H₂O₂-induced oxidative damage and inflammation. HUVECs were pretreated with quercetin or taraxasterol at concentrations ranging between 0 and 210 µM for 12 h, prior to being administered different concentrations of H₂O₂ for 4 h. Cell viability and levels of apoptosis were assessed through cell counting kit-8 (CCK-8) and terminal deoxynucleotidyl transferase dUTP nick end labeling assays, respectively, to determine the injury to the HUVECs. The viability loss in the H₂O₂-induced HUVECs was markedly restored in a concentration-dependent manner by pretreatment with quercetin or taraxasterol. This effect was accompanied by significantly decreased expression of vascular cell adhesion molecule 1 (VCAM-1) and cluster of differentiation (CD)80 for taraxasterol and that of CD80 for quercetin. In conclusion, the present study showed the protective effects of quercetin and taraxasterol against cell injury and inflammation in HUVECs and indicated that the effects were mediated via the downregulation of VCAM-1 and CD80 expression. This study has therefore served as a preliminary investigation on the anti-atherosclerotic and cardiovascular protective effects of quercetin and taraxasterol as dietary supplements.

Specific Inflammatory Stimuli Lead to Distinct Platelet Responses in Mice and Humans

Introduction

Diverse and multi-factorial processes contribute to the progression of cardiovascular disease. These processes affect cells involved in the development of this disease in varying ways, ultimately leading to atherothrombosis. The goal of our study was to compare the differential effects of specific stimuli – two bacterial infections and a Western diet – on platelet responses in ApoE^-/- mice, specifically examining inflammatory function and gene expression. Results from murine studies were verified using platelets from participants of the Framingham Heart Study (FHS; n = 1819 participants).

Methods

Blood and spleen samples were collected at weeks 1 and 9 from ApoE^-/- mice infected with Porphyromonas gingivalis or Chlamydia pneumoniae and from mice fed a Western diet for 9 weeks. Transcripts based on data from a Western diet in ApoE^-/- mice were measured in platelet samples from FHS using high throughput qRT-PCR.

Results

At week 1, both bacterial infections increased circulating platelet-neutrophil aggregates. At week 9, these cells individually localized to the spleen, while Western diet resulted in increased platelet-neutrophil aggregates in the spleen only. Microarray analysis of platelet RNA from infected or Western diet-fed mice at week 1 and 9 showed differential profiles. Genes, such as Serpina1a, Ttr, Fgg, Rpl21, and Alb, were uniquely affected by infection and diet. Results were reinforced in platelets obtained from participants of the FHS.

Conclusion

Using both human studies and animal models, results demonstrate that variable sources of inflammatory stimuli have the ability to influence the platelet phenotype in distinct ways, indicative of the diverse function of platelets in thrombosis, hemostasis, and immunity.

Modulation of platelet and monocyte function by the chemokine fractalkine (CX3 CL1) in cardiovascular disease

BACKGROUND

The chemokine fractalkine, CX3CL1, bears unique features within the chemokine family: it exists in a membrane bound form acting as an adhesion molecule and surface receptor; however, when cleaved by ADAM 10, it functions as a soluble chemokine. Fractalkine and its chemokine receptor CX3CR1 are known to have multiple roles in diverse human diseases, for example inflammatory diseases, rheumatoid arthritis, renal diseases and atherosclerosis.

MATERIALS AND METHODS

This review is based on the material obtained via PubMed up to November 2014. The key search terms used were 'fractalkine', 'CX3CL1', 'CX3CR1', 'cardiovascular disease', 'platelets', 'monocytes' and 'platelet-monocyte complexes'.

RESULTS

Atherosclerosis is recognized as a highly inflammatory disease, and it has become increasingly evident that the immune system plays an important role in atherogenesis and atheroprogression. Two blood cell populations are crucially involved in the early development of atherosclerotic lesions: monocytes and platelets. They are detected at vascular sites of endothelial dysfunction and are involved in inflammatory immune responses. These cells directly interact with each other, forming platelet-monocyte complexes that are increased in cardiovascular diseases. During the development of atherosclerosis, fractalkine mediates leukocyte recruitment to the inflamed endothelium, which promotes early formation of lesions. This process only effectively works in the presence of activated platelets. It has been suggested that fractalkine and its receptor contribute to platelet-monocyte aggregate formation underlining the two important impacts of this chemokine for platelets as well as monocytes.

CONCLUSION

Interesting data hint at a role of fractalkine for platelet activation, adhesion and subsequent monocyte recruitment to activated endothelial cells in cardiovascular diseases. However, the exact mechanisms remain to become unravelled.

Cytokines in atherosclerosis: Key players in all stages of disease and promising therapeutic targets

Atherosclerosis, a chronic inflammatory disorder of the arteries, is responsible for most deaths in westernized societies with numbers increasing at a marked rate in developing countries. The disease is initiated by the activation of the endothelium by various risk factors leading to chemokine-mediated recruitment of immune cells. The uptake of modified lipoproteins by macrophages along with defective cholesterol efflux gives rise to foam cells associated with the fatty streak in the early phase of the disease. As the disease progresses, complex fibrotic plaques are produced as a result of lysis of foam cells, migration and proliferation of vascular smooth muscle cells and continued inflammatory response. Such plaques are stabilized by the extracellular matrix produced by smooth muscle cells and destabilized by matrix metalloproteinase from macrophages. Rupture of unstable plaques and subsequent thrombosis leads to clinical complications such as myocardial infarction. Cytokines are involved in all stages of atherosclerosis and have a profound influence on the pathogenesis of this disease. This review will describe our current understanding of the roles of different cytokines in atherosclerosis together with therapeutic approaches aimed at manipulating their actions.

Vascular injury in diabetic db/db mice is ameliorated by atorvastatin: role of Rac1/2-sensitive Nox-dependent pathways

Oxidative stress [increased bioavailability of reactive oxygen species (ROS)] plays a role in the endothelial dysfunction and vascular inflammation, which underlie vascular damage in diabetes. Statins are cholesterol-lowering drugs that are vasoprotective in diabetes through unknown mechanisms. We tested the hypothesis that atorvastatin decreases NADPH oxidase (Nox)-derived ROS generation and associated vascular injury in diabetes. Lepr(db)/Lepr(db) (db/db) mice, a model of Type 2 diabetes and control Lepr(db)/Lepr(+) (db/+) mice were administered atorvastatin (10 mg/kg per day, 2 weeks). Atorvastatin improved glucose tolerance in db/db mice. Systemic and vascular oxidative stress in db/db mice, characterized by increased plasma TBARS (thiobarbituric acid-reactive substances) levels and exaggerated vascular Nox-derived ROS generation respectively, were inhibited by atorvastatin. Cytosol-to-membrane translocation of the Nox regulatory subunit p47(phox) and the small GTPase Rac1/2 was increased in vessels from db/db mice compared with db/+ mice, an effect blunted by atorvastatin. The increase in vascular Nox1/2/4 expression and increased phosphorylation of redox-sensitive mitogen-activated protein kinases (MAPKs) was abrogated by atorvastatin in db/db mice. Pro-inflammatory signalling (decreased IκB-α and increased NF-κB p50 expression, increased NF-κB p65 phosphorylation) and associated vascular inflammation [vascular cell adhesion molecule-1 (VCAM-1) expression and vascular monocyte adhesion], which were increased in aortas of db/db mice, were blunted by atorvastatin. Impaired acetylcholine (Ach)- and insulin (INS)-induced vasorelaxation in db/db mice was normalized by atorvastatin. Our results demonstrate that, in diabetic mice, atorvastatin decreases vascular oxidative stress and inflammation and ameliorates vascular injury through processes involving decreased activation of Rac1/2 and Nox. These findings elucidate redox-sensitive and Rac1/2-dependent mechanisms whereby statins protect against vascular injury in diabetes.

Role of chemokines in promoting instability of coronary atherosclerotic plaques and the underlying molecular mechanism

Our aim was to investigate the role of chemokines in promoting instability of coronary atherosclerotic plaques and the underlying molecular mechanism. Coronary angiography and intravascular ultrasound (IVUS) were performed in 60 stable angina pectoris (SAP) patients and 60 unstable angina pectoris (UAP) patients. The chemotactic activity of monocytes in the 2 groups of patients was examined in Transwell chambers. High-sensitivity C-reactive protein (hs-CRP), monocyte chemoattractant protein-1 (MCP-1), regulated on activation in normal T-cell expressed and secreted (RANTES), and fractalkine in serum were examined with ELISA kits, and expression of MCP-1, RANTES, and fractalkine mRNA was examined with real-time PCR. In the SAP group, 92 plaques were detected with IVUS. In the UAP group, 96 plaques were detected with IVUS. The plaques in the UAP group were mainly lipid 51.04% (49/96) and the plaques in the SAP group were mainly fibrous 52.17% (48/92). Compared with the SAP group, the plaque burden and vascular remodeling index in the UAP group were significantly greater than in the SAP group (P<0.01). Chemotactic activity and the number of mobile monocytes in the UAP group were significantly greater than in the SAP group (P<0.01). Concentrations of hs-CRP, MCP-1, RANTES, and fractalkine in the serum of the UAP group were significantly higher than in the serum of the SAP group (P<0.05 or P<0.01), and expression of MCP-1, RANTES, and fractalkine mRNA was significantly higher than in the SAP group (P<0.05). MCP-1, RANTES, and fractalkine probably promote instability of coronary atherosclerotic plaque.

Bestrophin 3 ameliorates TNFα-induced inflammation by inhibiting NF-κB activation in endothelial cells

Increasing evidences have suggested vascular endothelial inflammatory processes are the initiator of atherosclerosis. Bestrophin 3 (Best-3) is involved in the regulation of cell proliferation, apoptosis and differentiation of a variety of physiological functions, but its function in cardiovascular system remains unclear. In this study, we investigated the effect of Best-3 on endothelial inflammation. We first demonstrated that Best-3 is expressed in endothelial cells and decreased after tumor necrosis factor-α (TNFα) challenge. Overexpression of Best-3 significantly attenuated TNFα-induced expression of adhesion molecules and chemokines, and subsequently inhibited the adhesion of monocytes to human umbilical vein endothelial cells (HUVECs). Conversely, knockdown of Best-3 with siRNA resulted in an enhancement on TNFα-induced expression of adhesion molecules and chemokines and adhesion of monocytes to HUVECs. Furthermore, overexpression of Best-3 with adenovirus dramatically ameliorated inflammatory response in TNFα-injected mice. Mechanistically, we found up-regulation of Best-3 inhibited TNFα-induced IKKβ and IκBα phosphorylation, IκBα degradation and NF-κB translocation. Our results demonstrated that Best-3 is an endogenous inhibitor of NF-κB signaling pathway in endothelial cells, suggesting that forced Best-3 expression may be a novel approach for the treatment of vascular inflammatory diseases.