Statin treatment is associated with reduction in serum levels of receptor activator of NF-κB ligand and neutrophil activation in patients with severe carotid stenosis

Osteoprotegerin as an Emerging Biomarker of Carotid Artery Stenosis? A Scoping Review with Meta-Analysis

Objective: In developed countries, stroke is the fifth cause of death, with a high mortality rate, and with recovery to normal neurological function in one-third of survivors. Atherosclerotic occlusive disease of the extracranial part of the internal carotid artery and related embolic complications are common preventable causes of ischemic stroke (IS), attributable to 7-18% of all first-time cases. Osteoprotegerin (OPG), a soluble member of the tumor necrosis factor receptor (TNFR) superfamily, is considered a modulator of vascular calcification linked to vascular smooth muscle cell proliferation and collagen production in atherosclerotic plaques. Therefore, OPG emerges as a potential biomarker (BM) of calcified carotid plaques and carotid artery stenosis (CAS). Methods: We performed a literature search of PubMed on OPG in CAS and atherosclerosis published until 2024. Results: Increased levels of serum OPG were reported in both patients with symptomatic and asymptomatic CAS, and higher values were observed in those with unstable atherosclerotic plaques. Notably, increased OPG levels were observed regardless of the location of atherosclerosis, including coronary and other peripheral arteries. In addition, chronic kidney disease, the most significant confounder disturbing the association between vascular damage and circulating OPG levels, decreases the usefulness of OPG as a BM in CAS. Conclusions: Osteoprotegerin may be considered an emerging BM of global rather than cerebrovascular atherosclerosis. Its diagnostic significance in identifying patients with asymptomatic CAS and their monitoring is limited.

Phenotypes and functions of "aged" neutrophils in cardiovascular diseases

Neutrophils are important effector cells of innate immunity and undergo several phenotypic changes after release from the bone marrow. Neutrophils with a late life cycle phenotype are often referred to as "aged" neutrophils. These neutrophils undergo functional changes that accompany stimuli of inflammation, tissue senescence and injury, inducing their maturation and senescence in the circulation and locally in damaged tissues, forming a unique late-life neutrophil phenotype. "Aged" neutrophils, although attenuated in antibacterial capacity, are more active in aging and age-related diseases, exhibit high levels of mitochondrial ROS and mitochondrial DNA leakage, promote senescence of neighboring cells, and exacerbate cardiac and vascular tissue damage, including vascular inflammation, myocardial infarction, atherosclerosis, stroke, abdominal aortic aneurysm, and SARS-CoV-2 myocarditis. In this review, we outline the phenotypic changes of "aged" neutrophils characterized by CXCR4high/CD62Llow, investigate the mechanisms driving neutrophil aging and functional transformation, and analyze the damage caused by "aged" neutrophils to various types of heart and blood vessels. Tissue injury and senescence promote neutrophil infiltration and induce neutrophil aging both in the circulation and locally in damaged tissues, resulting in an "aged" neutrophil phenotype characterized by CXCR4high/CD62Llow. We also discuss the effects of certain agents, such as neutralizing mitochondrial ROS, scavenging IsoLGs, blocking VDAC oligomers and mPTP channel activity, activating Nrf2 activity, and inhibiting neutrophil PAD4 activity, to inhibit neutrophil NET formation and ameliorate age-associated cardiovascular disease, providing a new perspective for anti-aging therapy in cardiovascular disease.

Cholesterol and Immune Microenvironment: Path Towards Tumorigenesis

PURPOSE OF REVIEW

Since obesity is a major risk factor for many different types of cancer, examining one of the most closely associated comorbidities, such as hypercholesterolemia, is crucial to understanding how obesity causes cancer. Hypercholesterolemia is usually associated with many cardiovascular complications such as hypertension, angina, and atherosclerosis. In addition, cholesterol may be a major factor in increasing cancer risk. Cancer patients who received statins, an anti-hypercholesteremic medicine, demonstrated improved prognosis possibly through its effect on tumor proliferation, apoptosis, and oxidative stress. Cholesterol could also aid in tumor progression through reprogramming tumor immunological architecture and mediators. This review focuses on the immunomodulatory role of cholesterol on cellular and molecular levels, which may explain its oncogenic driving activity. We look at how cholesterol modulates tumor immune cells like dendritic cells, T cells, Tregs, and neutrophils. Further, this study sheds light on the modification of the expression pattern of the common cancer-related immune mediators in the tumor immune microenvironment, such as programmed cell death 1 (PD-1), cytotoxic T lymphocyte antigen-4 (CTLA-4), transforming growth factor-beta (TGF-β), interleukin 12 (IL-12), IL-23, and forkhead box protein P3 (FOXP3).

RECENT FINDINGS

We highlight relevant literature demonstrating cholesterol's immunosuppressive role, leading to a worse cancer prognosis. This review invites further research regarding the pathobiological role of cholesterol in many obesity-related cancers such as uterine fibroids, post-menopausal breast, colorectal, endometrial, kidney, esophageal, pancreatic, liver, and gallbladder cancers. This review suggests that targeting cholesterol synthesis may be a fruitful approach to cancer targeting, in addition to traditional chemotherapeutics.

Biomarkers of Neutrophil Activation in Patients with Symptomatic Chronic Peripheral Artery Disease Predict Worse Cardiovascular Outcome

Neutrophils play a role in cardiovascular (CV) disease. However, relatively scant evidence exists in the setting of peripheral artery disease (PAD). The aims of this study were to measure biomarkers of neutrophil activation in patients with symptomatic chronic PAD compared with healthy controls, to assess their association with PAD severity, and to evaluate their prognostic value in patients with PAD. The following circulating markers of neutrophil degranulation were tested: polymorphonuclear neutrophil (PMN) elastase, neutrophil gelatinase-associated lipocalin (NGAL), and myeloperoxidase (MPO). Neutrophil extracellular traps (NETs) were quantified by measuring circulating MPO–DNA complexes. Patients with PAD underwent a comprehensive series of vascular tests. The occurrence of 6-month major adverse CV (MACE) and limb events (MALE) was assessed. Overall, 110 participants were included, 66 of which had PAD. After adjustment for conventional CV risk factors, PMN-elastase (adjusted odds ratio [OR]: 1.008; 95% confidence interval [CI]: 1.002–1.015; p = 0.006), NGAL (adjusted OR: 1.045; 95%CI: 1.024–1.066; p < 0.001), and MPO (adjusted OR: 1.013; 95%CI: 1.001–1.024; p = 0.028) were significantly associated with PAD presence. PMN-elastase (adjusted hazard ratio [HR]: 1.010; 95%CI: 1.000–1.020; p = 0.040) and MPO (adjusted HR: 1.027; 95%CI: 1.004–1.051; p = 0.019) were predictive of 6-month MACE and/or MALE. MPO displayed fair prognostic performance on receiver operating characteristic (ROC) curve analyses, with an area under the curve (AUC) of 0.74 (95%CI: 0.56–0.91) and a sensitivity and specificity of 0.80 and 0.65, respectively, for a cut-off of 108.37 ng/mL. MPO–DNA showed a weak inverse correlation with transcutaneous oximetry (TcPO2) on proximal foot (adjusted ρ −0.287; p = 0.032). In conclusion, in patients with symptomatic chronic PAD, enhanced neutrophil activity may be associated with an increased risk of acute CV events, rather than correlate with disease severity. Further research is needed to clarify the role of neutrophils in PAD natural history.

Association between plaque vulnerability and neutrophil extracellular traps (NETs) levels: The Plaque At RISK study

Carotid atherosclerotic plaque rupture and its sequelae are among the leading causes of acute ischemic stroke. The risk of rupture and subsequent thrombosis is, among others, determined by vulnerable plaque characteristics and linked to activation of the immune system, in which neutrophil extracellular traps (NETs) potentially play a role. The aim of this study was to investigate how plaque vulnerability is associated with NETs levels. We included 182 patients from the Plaque At RISK (PARISK) study in whom carotid imaging was performed to measure plaque ulceration, fibrous cap integrity, intraplaque hemorrhage, lipid-rich necrotic core, calcifications and plaque volume. Principal component analysis generated a ‘vulnerability index’ comprising all plaque characteristics. Levels of the NETs marker myeloperoxidase-DNA complex were measured in patient plasma. The association between the vulnerability index and low or high NETs levels (dependent variable) was assessed by logistic regression. No significant association between the vulnerability index and NETs levels was detected in the total population (odds ratio 1.28, 95% confidence interval 0.90–1.83, p = 0.18). However, in the subgroup of patients naive to statins or antithrombotic medication prior to the index event, this association was statistically significant (odds ratio 2.08, 95% confidence interval 1.04–4.17, p = 0.04). Further analyses revealed that this positive association was mainly driven by intraplaque hemorrhage, lipid-rich necrotic core and ulceration. In conclusion, plaque vulnerability is positively associated with plasma levels of NETs, but only in patients naive to statins or antithrombotic medication prior to the index event.

Treatment strategies for asymptomatic carotid artery stenosis in the era of lipid-lowering drugs: protocol for a systematic review and network meta-analysis

INTRODUCTION

Carotid endarterectomy (CEA), carotid artery stenting (CAS) and best medical therapy (BMT) are the major treatments used for significant asymptomatic carotid artery stenosis (ACAS, ≥50%). However, the widespread use of lipid-lowering drugs in this century has improved BMT outcomes. This study aims to compare the treatment efficacy of current BMT, CEA+BMT and CAS+BMT in patients with significant ACAS.

METHODS AND ANALYSIS

This protocol was designed based on the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. Publication time for studies will be set from 1 January 2000 to 1 June 2020. We will search three databases: PubMed, EMBASE and The Cochrane Library. Suitable randomised controlled studies will be screened. The primary outcomes will include short-term and long-term mortality, stroke and myocardial infarction. OR and HR for dichotomous data and time-to-event data with 95% CIs will be calculated. Treatment effects among different therapies will be ranked according to the surface under the cumulative ranking curve and mean rank. A comprehensive evaluation of the risk of bias, heterogeneity and transitivity will be performed before data synthesis. Consistency and evidence quality will also be assessed.

ETHICS AND DISSEMINATION

There will be no need for ethics approval as this systematic review is a summary and analysis of existing literature. Final results may be presented in international conferences or a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42019138942.

Regression of asymptomatic intracranial arterial stenosis by aggressive medical management with a lipid-lowering agent

Objective

The incidence rate of stroke as a result of intracranial arterial stenosis (ICAS) is higher in Asian countries than in the West. We aimed to analyze the regression, lack of change, or progression of asymptomatic ICAS after the administration of rosuvastatin and associated factors.

Methods

The patients who had undergone computed tomography angiography (CTA) at our hospital and had been diagnosed with ICAS with no ischemic event in the stenosed vascular territory were included in the study. They were administered 20mg of rosuvastatin per day. After a follow-up period of at least 6 months after treatment, the patients were examined using CTA again and the clinical information and imaging results were analyzed.

Results

In total, 48 patients were diagnosed with asymptomatic ICAS. During the final follow-up examination, it was found that the stenotic lesion regressed in 30 patients, whereas it remained unchanged or progressed without any adverse effects in 18 patients. In univariate analysis, the regressed group showed significantly higher differences in the levels of total cholesterol and low-density lipoprotein (LDL) between their initial and final values (both, p=0.031 for both). In the multivariate analysis, a significantly higher difference in the levels of LDL between its initial and final measurement was seen in the regressed group (p=0.035, odds ratio(OR) 3.9).

Conclusions

Rosuvastatin was found to have better lipid-lowering effects for total cholesterol and particularly LDL in patients whose ICAS had regressed. We concluded that rosuvastatin administration can be recommended for the treatment of patients with asymptomatic ICAS.

Expression of Longevity Genes Induced by a Low-Dose Fluvastatin and Valsartan Combination with the Potential to Prevent/Treat "Aging-Related Disorders"

The incidence of aging-related disorders may be decreased through strategies influencing the expression of longevity genes. Although numerous approaches have been suggested, no effective, safe, and easily applicable approach is yet available. Efficacy of low-dose fluvastatin and valsartan, separately or in combination, on the expression of the longevity genes in middle-aged males, was assessed. Stored blood samples from 130 apparently healthy middle-aged males treated with fluvastatin (10 mg daily), valsartan (20 mg daily), fluvastatin-valsartan combination (10 and 20 mg, respectively), and placebo (control) were analyzed. They were taken before and after 30 days of treatment and, additionally, five months after treatment discontinuation. The expression of the following longevity genes was assessed: SIRT1, PRKAA, KLOTHO, NFE2L2, mTOR, and NF-κB. Treatment with fluvastatin and valsartan in combination significantly increased the expression of SIRT1 (1.8-fold; p < 0.0001), PRKAA (1.5-fold; p = 0.262) and KLOTHO (1.7-fold; p < 0.0001), but not NFE2L2, mTOR and NF-κB. Both fluvastatin and valsartan alone significantly, but to a lesser extent, increased the expression of SIRT1, and did not influence the expression of other genes. Five months after treatment discontinuation, genes expression decreased to the basal levels. In addition, analysis with previously obtained results revealed significant correlation between SIRT1 and both increased telomerase activity and improved arterial wall characteristics. We showed that low-dose fluvastatin and valsartan, separately and in combination, substantially increase expression of SIRT1, PRKAA, and KLOTHO genes, which may be attributed to their so far unreported pleiotropic beneficial effects. This approach could be used for prevention of ageing (and longevity genes)–related disorders.

The role of OPG/RANKL in the pathogenesis of diabetic cardiovascular disease

Cardiovascular (CV) disease is the leading cause of mortality in patients with type 2 diabetes mellitus. A major factor in the pathogenesis of CV disease is vascular calcification (VC), which is accelerated in type 2 diabetes mellitus. Calcification of the vessel wall contributes to vascular stiffness and left ventricular hypertrophy whereas intimal calcification may predispose to plaque rupture and CV death. The pathogenesis of VC is complex but appears to be regulated by the osteoprotegerin (OPG)/receptor activator of nuclear factor-κB ligand (RANKL) signaling pathway, which is involved in bone remodeling. Within the bone, OPG prevents RANKL from binding to receptor activator of nuclear factor-κB and inhibiting bone resorption. Outside of the bone, the clinical significance of OPG blocking RANKL is not well understood, but OPG knockout mice that lack OPG develop early and severe VC. This minireview outlines some of the research on OPG/RANKL in the pathogenesis of VC and discusses potential therapies, which may reduce VC and CV burden in humans.

Innate and adaptive immunity in atherosclerosis

Atherosclerosis is a chronic inflammatory disorder of the large and medium-size arteries characterized by the subendothelial accumulation of cholesterol, immune cells, and extracellular matrix. At the early onset of atherogenesis, endothelial dysfunction takes place. Atherogenesis is further triggered by the accumulation of cholesterol-carrying low-density lipoproteins, which acquire properties of damage-associated molecular patterns and thereby trigger an inflammatory response. Following activation of the innate immune response, mainly governed by monocytes and macrophages, the adaptive immune response is started which further promotes atherosclerotic plaque formation. In this review, an overview is given describing the role of damage-associated molecular patterns, NLRP3 inflammasome activation, and innate and adaptive immune cells in the atherogenesis process.

Upregulated expression of human cathelicidin LL-37 in hypercholesterolemia and its relationship with serum lipid levels

Dyslipidemia in patients with hypercholesterolemia has been recently linked to increased human cathelicidin LL-37 (LL-37) serum concentration. We tested a hypothesis that upregulated expression of LL-37 gene in peripheral blood leucocytes is involved in dyslipidemia in patients with hypercholesteremia. Patients with hypercholesterolemia were used in the study. Expression of LL-37 and human glyceraldehyde-3-phosphate dehydrogenase in peripheral blood leucocytes were quantified by real-time RT-PCR. Serum LL-37 concentration was estimated by enzyme-linked immunosorbent assay. Serum lipid levels were assessed by absorptiometry in all cases. Patients with hypercholesterolemia as compared to control ones were characterized by (a) an up-regulation of LL-37 gene expression in peripheral blood leucocytes with parallel increase of serum LL-37 concentration and (b) an increase of serum total and low-density lipoprotein cholesterol concentrations. Patients with hypercholesterolemia after a treatment with atorvastatin calcium 20 mg daily as compared to that patients before the treatment: an down-regulation of LL-37 gene expression in peripheral blood leucocytes with parallel decrease of serum LL-37 concentration. We also found significant correlation between serum LL-37 and high-density lipoprotein cholesterol levels (r = 0.7290, P < 0.0001). The results suggest that hypercholesterolemia is associated with an increased LL-37 gene expression in peripheral blood leucocytes. The correlation between serum LL-37 and high-density lipoprotein cholesterol levels suggests that LL-37 may play a key role in regulation of cholesterol levels in hypercholesterolemia.

Prognostic significance of arterial stiffness and osteoprotegerin in patients with stable coronary artery disease

BACKGROUND

Arterial stiffness and vascular calcification significantly contribute to coronary atherosclerosis progression. The prognostic value of increased arterial stiffness and vascular calcification in subjects with stable coronary artery disease (CAD) after percutaneous coronary intervention(PCI) is currently under question.

MATERIALS AND METHODS

We randomly enrolled 262 patients with stable CAD 1 month after successful PCI. Carotid-femoral pulse wave velocity (PWV) was measured as a well-established index of central aortic stiffness. Osteoprotegerin (OPG) plasma levels were measured as a biomarker of vascular calcification. Patients were followed up prospectively up to 52 months. The primary endpoint was the composite of death from cardiovascular causes, myocardial infarction, stroke or hospitalization for cardiovascular causes.

RESULTS

During the follow-up period, 48 patients presented the primary composite endpoint. Subjects who presented the primary endpoint, compared to subjects free of cardiovascular events, had significantly increased PWV (9.45 ± 2.19 m/s vs 8.73 ± 2.07 m/s, P = .04) and OPG levels (4.21 ± 2.19 pmol/L vs 3.18 ± 1.74 pmol/L, P = .003). Survival analysis indicated that PWV predicted adverse cardiac events MACE (Hazard ratio = 1.29 95%CI: 1.07-1.57, P = .008) independently from confounders such as age, sex, smoking habits, ejection fraction, extent of coronary artery disease, hypertension and diabetes mellitus. Interestingly, for every increase in pulse wave velocity by 1 m/s, there is an anticipated increase in the risk of major adverse cardiovascular event (MACE) by 29%.

CONCLUSIONS

These findings extend the current knowledge concerning the role of arterial stiffness as powerful biomarkers in cardiovascular disease. Measurement of PWV might have a role in ascertaining prognosis and managing treatment in patients with stable CAD after PCI.

P2X7 receptor antagonism modulates IL-1β and MMP9 in human atherosclerotic vessels

In atherosclerosis, matrix metallopeptidases (MMPs) contribute to plaque rupture through weakening of the fibrous cap. Pleiotropic P2X purinoceptor 7 (P2X7), expressed in the carotid plaque (PL), is involved in interleukin 1 beta (IL-1β) release that may influence MMP9 generation, thus their possible modulation through acting on P2X7 was investigated. P2X7-related machinery was characterized and the effects of P2X7 antagonists (A740003, KN62) and MMPs inhibitors (Batimastat, Ro28-2653) were studied in ex-vivo tissue cultures of human PL’s vs. non-atherosclerotic internal mammary artery (IMA) by using molecular biology, immune-biochemical and microscopy methodologies. We highlighted atherosclerosis-related differences between PLs and IMAs molecular patterns, and their responsivity to P2X7 antagonism. High IL-1β tissue content was associated with PLs morphology and instability/vulnerability. We demonstrated that A740003, but not KN62, decreased IL-1β and MMP9 independently from NLR family pyrin domain containing 3, but in relationship with patient’s smoking status. Acting downstream P2X7 by MMPs inhibitors, diminished IL-1β mRNA without transcriptional effect at MMP9, possibly because the assumption of statin by patients. These data firstly demonstrated A740003 suitability as a specific tool to decrease inflammatory status in human vessels and might support the design of studies applying P2X7 antagonists for the local targeting and tailored therapy of atherosclerosis.

Suppression of Neutrophil-Mediated Tissue Damage-A Novel Skill of Mesenchymal Stem Cells

Mesenchymal stem cells (MSCs) are crucial for tissue homeostasis and regeneration. Though of prime interest, their potentially protective role on neutrophil-induced tissue damage, associated with high morbidity and mortality, has not been explored in sufficient detail. Here we report the therapeutic skill of MSCs to suppress unrestrained neutrophil activation and to attenuate severe tissue damage in a murine immune-complex mediated vasculitis model of unbalanced neutrophil activation. MSC-mediated neutrophil suppression was due to intercellular adhesion molecule 1-dependent engulfment of neutrophils by MSCs, decreasing overall neutrophil numbers. Similar to MSCs in their endogenous niche of murine and human vasculitis, therapeutically injected MSCs via upregulation of the extracellular superoxide dismutase (SOD3), reduced super-oxide anion concentrations and consequently prevented neutrophil death, neutrophil extracellular trap formation and spillage of matrix degrading neutrophil elastase, gelatinase and myeloperoxidase. SOD3-silenced MSCs did not exert tissue protective effects. Thus, MSCs hold substantial therapeutic promise to counteract tissue damage in conditions with unrestrained neutrophil activation.

Role of neutrophils in atherogenesis: an update

BACKGROUND

The role of neutrophils in the beginning and the progression of the atherosclerotic process did not receive much attention until the last years. On the contrary, recent data, in both the experimental animals and humans, suggest important effects of these cells with possible clinical consequences.

MATERIALS AND METHODS

This narrative review was based on the papers found on PubMed and MEDLINE up to July 2015. The search terms used were 'neutrophil, atherosclerosis' in combination with 'recruitment, chemokine, plaque destabilization and pathophysiology'.

RESULTS

Different models demonstrate the presence and the actions of neutrophils in the early steps of the atherogenesis confirming the fundamental role of these cells in the response of the innate immune system to different pathogens (in this context the modified lipoproteins). However, also the late phases of the atherosclerotic process, in particular the destabilization of a mature plaque, seem to be modulated by the neutrophils, possibly through the interaction with recently discovered biological systems such as the endocannabinoids.

CONCLUSIONS

The understanding of the mechanisms involved in the modulation exerted by neutrophils in atherosclerosis is pivotal in terms of the complete definition of the overall picture. This approach will certainly give us new targets and new pharmacological opportunities for the anti-inflammatory strategy of the cardiovascular prevention.

Ethanol extract of Zhongtian hawthorn lowers serum cholesterol in mice by inhibiting transcription of 3-hydroxy-3-methylglutaryl-CoA reductase via nuclear factor-kappa B signal pathway

Hawthorn is a berry-like fruit from the species of Crataegus. In China, it has another more famous name, Shan-Zha, which has been used to improve digestion as a traditional Chinese medicine or food for thousands of years. Moreover, during the last decades, hawthorn has received more attention because of its potential to treat cardiovascular diseases. However, currently, only fruits of C. pinnatifida and C. pinnatifida var. major are included as Shan-Zha in the Chinese Pharmacopoeia. In this study, our results showed that the ethanol extract of Zhongtian hawthorn, a novel grafted cultivar of C. cuneata (wild Shan-Zha), could markedly reduce body weight and levels of serum total cholesterol, triglyceride, low-density lipoprotein cholesterol, and liver cholesterol of hyperlipidemia mice. It could suppress the stimulation effect of high-fat diet on the transcription of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) and p65, and counteract the downregulation of CYP7A1 and LDLR. In addition, the results of luciferase reporter assay and Western blot showed that the transcriptional activity of HMGCR promoter was inhibited by Zhongtian hawthorn ethanol extract in a dose-dependent manner, while overexpression of p65 could reverse this transcriptional repression effect. These results suggested that Zhongtian hawthorn could provide health benefits by counteracting the high-fat diet-induced hypercholesteolemic and hyperlipidemic effects in vivo, and the mechanism underlying this event was mainly dependent on the suppressive effect of Zhongtian hawthorn ethanol extract on the transcription of HMGCR via nuclear factor-kappa B (NF-κB) signal pathway. Therefore, this novel cultivar of hawthorn cultivar which has much bigger fruits, early bearing, high yield, cold resistance, and drought resistance, might be considered as a good alternative to Shan-Zha and has great value in the food and medicine industry. In addition, to our best knowledge, this is also the first report that the extract of Crataegus could suppress the transcription of HMGCR via NF-κB signal pathway.

Icaritin Inhibits Collagen Degradation-Related Factors and Facilitates Collagen Accumulation in Atherosclerotic Lesions: A Potential Action for Plaque Stabilization

Most acute coronary syndromes result from rupture of vulnerable atherosclerotic plaques. The collagen content of plaques may critically affect plaque stability. This study tested whether Icaritin (ICT), an intestinal metabolite of Epimedium-derived flavonoids, could alter the collagen synthesis/degradation balance in atherosclerotic lesions. Rabbits were fed with an atherogenic diet for four months. Oral administration of ICT (10 mg·kg(-1)·day(-1)) was started after two months of an atherogenic diet and lasted for two months. The collagen degradation-related parameters, including macrophages accumulation, content and activity of interstitial collagenase-1 (MMP-1), and the collagen synthesis-related parameters, including amount and distribution of smooth muscle cells (SMC) and collagen mRNA/protein levels, were evaluated in the aorta. ICT reduced plasma lipid levels, inhibited macrophage accumulation, lowered MMP-1 mRNA and protein expression, and suppressed proteolytic activity of pro-MMP-1 and MMP-1 in the aorta. ICT changed the distribution of the SMCs towards the fibrous cap of lesions without increasing the amount of SMCs. Higher collagen protein content in lesions and aorta homogenates was observed with ICT treatment compared with the atherogenic diet only, without altered collagen mRNA level. These results suggest that ICT could inhibit the collagen degradation-related factors and facilitate collagen accumulation in atherosclerotic lesions, indicating a new potential of ICT in atherosclerotic plaques.

Regulation and involvement of matrix metalloproteinases in vascular diseases

Matrix metalloproteinases (MMPs) are a family of zinc dependent endopeptidases whose main function is to degrade and deposit structural proteins within the extracellular matrix (ECM). A dysregulation of MMPs is linked to vascular diseases. MMPs are classified into collagenases, gelatinases, membrane-type, metalloelastase, stromelysins, matrilysins, enamelysins, and unclassified subgroups. The production of MMPs is stimulated by factors such as oxidative stress, growth factors and inflammation which lead to its up- or down-regulation with subsequent ECM remodeling. Normally, excess activation of MMPs is controlled by their endogenous inhibitors, tissue inhibitors of metalloproteinases (TIMPs). An imbalance of MMPs and TIMPs has been implicated in hypertension, atherosclerotic plaque formation and instability, aortic aneurysms and varicose vein wall remodeling. Also, recent evidence suggests epigenetic regulation of some MMPs in angiogenesis and atherosclerosis. Over the years, pharmacological inhibitors of MMPs have been used to modify or prevent the development of the disease with some success. In this review, we discuss recent advances in MMP biology, and their involvement in the manifestation of vascular disease.

Neutrophil's weapons in atherosclerosis

Neutrophils are important components of immunity associated with inflammatory responses against a broad spectrum of pathogens. These cells could be rapidly activated by proinflammatory stimuli and migrate to the inflamed and infected sites where they release a variety of cytotoxic molecules with antimicrobial activity. Neutrophil antibacterial factors include extracellular proteases, redox enzymes, antimicrobial peptides, and small bioactive molecules. In resting neutrophils, these factors are stored in granules and released upon activation during degranulation. These factors could be also secreted in a neutrophil-derived microparticle-dependent fashion. Neutrophils exhibit a unique property to produce neutrophil extracellular traps (NETs) composed of decondensed chromatin and granular proteins to catch and kill bacteria. Neutrophil-released factors are efficient in inactivation and elimination of pathogens through oxidation-dependent or independent damage of bacterial cells, inactivation and neutralization of virulence factors and other mechanisms. However, in chronic atherosclerosis-associated inflammation, protective function of neutrophils could be impaired and misdirected against own cells. This could lead to deleterious effects and progressive vascular injury. In atherogenesis, a pathogenic role of neutrophils could be especially seen in early stages associated with endothelial dysfunction and induction of vascular inflammation and in late atherosclerosis associated with plaque rupture and atherothrombosis. Assuming a prominent impact of neutrophils in cardiovascular pathology, developing therapeutic strategies targeting neutrophil-specific antigens could have a promising clinical potential.

Serum osteopontin levels are upregulated and predict disability after an ischaemic stroke

BACKGROUND

After an acute ischaemic stroke (AIS), several inflammatory biomarkers have been investigated, but their predictive role on functional recovery remains to be validated. Here, we investigated the prognostic relevance of biomarkers related to atherosclerotic plaque calcification, such as osteopontin (OPN), osteoprotegerin (OPG) and the receptor activator of nuclear factor kappa-B ligand (RANKL) in a cohort of patients with AIS (n = 90) during 90-day follow-up.

MATERIALS AND METHODS

Radiological and clinical examinations as well as blood sampling were performed at admission and at days 1, 7 and 90 from the event. Validated scores [such as modified Rankin scale (mRS) and the National Institutes of Health Stroke Scale (NIHSS)] were used to assess poststroke outcome. Serum levels of OPN, OPG and RANKL were measured by colorimetric enzyme-linked immunosorbent assay (ELISA).

RESULTS

When compared to the admission, OPN serum levels increased at day 7. Serum OPN levels at this time point were positively correlated with both ischaemic lesion volume and NIHSS at days 7 and 90. A cut-off of 30.53 ng/mL was identified for serum OPN by receiver operating characteristic (ROC) curve analysis. Adjusted logistic regression showed that serum OPN levels at day 7 predicted worse mRS at day 90 [OR 4.13 (95% CI 1.64-10.36); P = 0.002] and NIHSS [1.49 (95% CI 1.16-1.99); P = 0.007], independently of age, gender, hypertension and thrombolysis.

CONCLUSIONS

Serum levels of OPN, but not OPG and RANKL, peaked at day 7 after AIS and predicted worse neurological scores. Therefore, OPN might have a pathophysiological and clinical relevance after AIS.

Carotid atherosclerotic plaque stenosis: the stabilizing role of statins

BACKGROUND

Both pathophysiology and treatments of carotid atherosclerotic plaque stenosis represent two interesting fields of strong scientific investigation. Among different drugs, safety and efficacy of statin treatment have been widely investigated and proved.

MATERIALS AND METHODS

This narrative review is based on the material searched for and obtained via MEDLINE and PubMed up to March 2014. The search terms we used were: 'carotid plaque, intima-media thickness, plaque burden, stroke' in combination with 'statins, pleiotropic effects, HMG-CoA reductase inhibitors, lipid-lowering drugs'.

RESULTS

Carotid stenosis represents both a useful parameter to evaluate the atherosclerotic burden and a target for therapeutic (medical or surgical) decisions. Statins do not only improve the lipid profile, but also induce some 'pleiotropic' anti-inflammatory activities that contribute to carotid plaque stabilization. Statin-mediated protective activities are under active investigation at subclinical levels with the potential benefit of advanced imaging techniques. However, considering that some new techniques (excepted B-mode ultrasound) remain quite expensive, they can have for the moment an important role in research, but not in the clinical field.

CONCLUSIONS

Emerging evidence suggests that statin treatment improves carotid atherosclerosis, inducing a partial regression of plaque inflammation and size. Innovative imaging techniques might also ameliorate the identification of patients at high risk of cerebrovascular and coronary events, for which preventive statin treatments might be essential.