The Role of Vascular Aging in Atherosclerotic Plaque Development and Vulnerability

Long non-coding RNAs H19 and NKILA are associated with the risk of death and lacunar stroke in the elderly population

INTRODUCTION

Differential expression of long non-coding RNAs (lncRNAs) is a hallmark of cardiovascular aging, cerebrovascular diseases, and neurodegenerative disorders. This research article investigates the association between a panel of lncRNAs and the risk of death and ischemic stroke in a cohort of non-institutionalized elderly subjects.

METHOD

A total of 361 healthy individuals aged 75 years old, prospectively recruited in the Vienna Transdanube Aging (VITA) cohort, were included. Expression of lncRNAs at baseline was assessed using quantitative polymerase chain reaction PCR with pre-amplification reaction, using 18S for normalization. The primary endpoint was all-cause mortality; the secondary endpoint was the incidence of new ischemic brain lesions. Death was assessed over a 14-year follow-up, and ischemic brain lesions were evaluated by magnetic resonance imaging (MRI) over a 90-month follow-up. Ischemic brain lesions were divided into large brain infarcts (Ø≥ 1.5 cm) or lacunes (Ø< 1.5 cm) RESULTS: The primary endpoint occurred in 53.5 % of the study population. The incidence of the secondary endpoint was 16 %, with a 3.3 % being large brain infarcts, and a 12.7 % lacunes. After adjustment for potential confounders, the lncRNA H19 predicted the incidence of the primary endpoint (HR 1.194, 95 % C.I. 1.012-1.409, p = 0.036), whereas the lncRNA NKILA was associated with lacunar stroke (HR 0.571, 95 % C.I. 0.375-0.868, p = 0.006).

CONCLUSION

In a prospective cohort of non-institutionalized elderly subjects, high levels of lncRNA H19 are associated with a higher risk of death, while low levels of lncRNA NKILA predict an increased risk of lacunar stroke.

Contrast-Enhanced Ultrasound Feasibility in Assessing Carotid Plaque Vulnerability-Narrative Review

The risk assessment for carotid atherosclerotic lesions involves not only determining the degree of stenosis but also plaque morphology and its composition. Recently, carotid contrast-enhanced ultrasound (CEUS) has gained importance for evaluating vulnerable plaques. This review explores CEUS's utility in detecting carotid plaque surface irregularities and ulcerations as well as intraplaque neovascularization and its alignment with histology. Initial indications suggest that CEUS might have the potential to anticipate cerebrovascular incidents. Nevertheless, there is a need for extensive, multicenter prospective studies that explore the relationships between CEUS observations and patient clinical outcomes in cases of carotid atherosclerotic disease.

Endothelial Dysfunction and Chronic Inflammation: The Cornerstones of Vascular Alterations in Age-Related Diseases

Vascular diseases of the elderly are a topic of enormous interest in clinical practice, as they have great epidemiological significance and lead to ever-increasing healthcare expenditures. The mechanisms underlying these pathologies have been increasingly characterized over the years. It has emerged that endothelial dysfunction and chronic inflammation play a diriment role among the most relevant pathophysiological mechanisms. As one can easily imagine, various processes occur during aging, and several pathways undergo irreversible alterations that can promote the decline and aberrations that trigger the diseases above. Endothelial dysfunction and aging of circulating and resident cells are the main characteristics of the aged organism; they represent the framework within which an enormous array of molecular abnormalities occur and contribute to accelerating and perpetuating the decline of organs and tissues. Recognizing and detailing each of these dysfunctional pathways is helpful for therapeutic purposes, as it allows one to hypothesize the possibility of tailoring interventions to the damaged mechanism and hypothetically limiting the cascade of events that drive the onset of these diseases. With this paper, we have reviewed the scientific literature, analysing the pathophysiological basis of the vascular diseases of the elderly and pausing to reflect on attempts to interrupt the vicious cycle that connotes the diseases of aging, laying the groundwork for therapeutic reasoning and expanding the field of scientific research by moving from a solid foundation.

Inflammation, Oxidative Stress, Vascular Aging And Atherosclerotic Ischemic Stroke

Vascular aging is a crucial risk factor for atherosclerotic ischemic stroke. Vascular aging is characterized by oxidative stress, endothelial dysfunction, inflammation, intimal and media thickening, as well as the gradual development of arterial stiffness, among other pathophysiological features. Regarding oxidative stress, increased concentration of reactive oxygen and nitrogen species is linked to atherosclerotic ischemic stroke in vascular aging. Additionally, oxidative stress is associated with an inflammatory response. Inflammation is related to aging through the "inflammaging" theory, which is characterized by decreased ability to cope with a variety of stressors, in combination with an increased pro-inflammatory state. Vascular aging is correlated with changes in cerebral arteries that are considered predictors of the risk for atherosclerotic ischemic stroke. The aim of the present review is to present the role of oxidative stress and inflammation in vascular aging, as well as their involvement in atherosclerotic ischemic stroke.

Sirtuin 5 promotes arterial thrombosis by blunting the fibrinolytic system

AIMS

Arterial thrombosis as a result of plaque rupture or erosion is a key event in acute cardiovascular events. Sirtuin 5 (SIRT5) belongs to the lifespan-regulating sirtuin superfamily and has been implicated in acute ischaemic stroke and cardiac hypertrophy. This project aims at investigating the role of SIRT5 in arterial thrombus formation.

METHODS AND RESULTS

Sirt5 transgenic (Sirt5Tg/0) and knock-out (Sirt5-/-) mice underwent photochemically induced carotid endothelial injury to trigger arterial thrombosis. Primary human aortic endothelial cells (HAECs) were treated with SIRT5 silencing-RNA (si-SIRT5) as well as peripheral blood mononuclear cells from acute coronary syndrome (ACS) patients and non-ACS controls (case-control study, total n = 171) were used to increase the translational relevance of our data. Compared to wild-type controls, Sirt5Tg/0 mice displayed accelerated arterial thrombus formation following endothelial-specific damage. Conversely, in Sirt5-/- mice, arterial thrombosis was blunted. Platelet function was unaltered, as assessed by ex vivo collagen-induced aggregometry. Similarly, activation of the coagulation cascade as assessed by vascular and plasma tissue factor (TF) and TF pathway inhibitor expression was unaltered. Increased thrombus embolization episodes and circulating D-dimer levels suggested augmented activation of the fibrinolytic system in Sirt5-/- mice. Accordingly, Sirt5-/- mice showed reduced plasma and vascular expression of the fibrinolysis inhibitor plasminogen activator inhibitor (PAI)-1. In HAECs, SIRT5-silencing inhibited PAI-1 gene and protein expression in response to TNF-α. This effect was mediated by increased AMPK activation and reduced phosphorylation of the MAP kinase ERK 1/2, but not JNK and p38 as shown both in vivo and in vitro. Lastly, both PAI-1 and SIRT5 gene expressions are increased in ACS patients compared to non-ACS controls after adjustment for cardiovascular risk factors, while PAI-1 expression increased across tertiles of SIRT5.

CONCLUSION

SIRT5 promotes arterial thrombosis by modulating fibrinolysis through endothelial PAI-1 expression. Hence, SIRT5 may be an interesting therapeutic target in the context of atherothrombotic events.

Inflamm-ageing: the role of inflammation in age-dependent cardiovascular disease

The ongoing worldwide increase in life expectancy portends a rising prevalence of age-related cardiovascular (CV) diseases in the coming decades that demands a deeper understanding of their molecular mechanisms. Inflammation has recently emerged as an important contributor for CV disease development. Indeed, a state of chronic sterile low-grade inflammation characterizes older organisms (also known as inflamm-ageing) and participates pivotally in the development of frailty, disability, and most chronic degenerative diseases including age-related CV and cerebrovascular afflictions. Due to chronic activation of inflammasomes and to reduced endogenous anti-inflammatory mechanisms, inflamm-ageing contributes to the activation of leucocytes, endothelial, and vascular smooth muscle cells, thus accelerating vascular ageing and atherosclerosis. Furthermore, inflamm-ageing promotes the development of catastrophic athero-thrombotic complications by enhancing platelet reactivity and predisposing to plaque rupture and erosion. Thus, inflamm-ageing and its contributors or molecular mediators might furnish targets for novel therapeutic strategies that could promote healthy ageing and conserve resources for health care systems worldwide. Here, we discuss recent findings in the pathophysiology of inflamm-ageing, the impact of these processes on the development of age-related CV diseases, results from clinical trials targeting its components and the potential implementation of these advances into daily clinical practice.

Predictors of adverse cardiovascular events in patients with coronary artery disease after percutaneous coronary intervention

Aim. To identify predictors of major adverse cardiovascular events (MACE) in patients with coronary artery disease (CAD) after percutaneous coronary intervention (PCI).

Material and methods. This prospective single-center study included 225 patients with stable CAD requiring drug-eluting stent implantation. The average follow-up period for patients was 14,5 (6;23) months. Levels of glycated hemoglobin (HbA1c), insulin, tumor necrosis factor (TNF)-α, interleukin-6 (IL-6), interleukin-10 (IL-10), endothelin-1 (ET-1) and the serum lipid profile were evaluated. Insulin resistance was assessed by the HOMA-IR index. The patients were divided into 2 groups: group 1 (n=98) — patients with MACE, group 2 (n=127) — patients without MACE over the follow-up period.

Results. During the follow-up period, MACE were recorded in 43,5% of patients, of which: fatal outcome in 3 (3,1%) patients, acute coronary syndrome (ACS) — 14 (14,3%), decompensated heart failure (HF) — 8 (8,2%), non-fatal myocardial infarc tion (MI) — 4 (4,1%), stroke — 3 (3,1%), in-stent restenosis — 18 (18,4%), target vessel revascularization due to progression of atherosclerosis — 25 (25,4%), lifethreatening arrhythmias — 18 (18,4%), implantation of a cardiac resynchronization therapy defibrillator — 5 (5%). To determine critical levels for quantitative predictors, ROC curves were created with threshold values that increase the likelihood of MACE.

Conclusion. As a result of the study, we found that the waist-to-hip ratio >1,0495, the HOMA-IR index >3,13 and the endothelin-1 >0,75 mmol/L are independent predictors of unfavorable prognosis in patients with CAD after PCI.

Interleukin-1β Mediates Arterial Thrombus Formation via NET-Associated Tissue Factor

CANTOS reported reduced secondary atherothrombotic events in patients with residual inflammatory risk treated with the inhibitory anti-IL-1β antibody, Canakinumab. Yet, mechanisms that underlie this benefit remain elusive. Recent work has implicated formation of neutrophil extracellular traps (NETosis) in arterial thrombosis. Hence, the present study explored the potential link between IL-1β, NETs, and tissue factor (TF)—the key trigger of the coagulation cascade—in atherothrombosis. To this end, ST-elevation myocardial infarction (STEMI) patients from the Swiss multicenter trial SPUM-ACS were retrospectively and randomly selected based on their CRP levels. In particular, 33 patients with STEMI and high C-reactive protein (CRP) levels (≥ 10 mg/L) and, 33 with STEMI and low CRP levels (≤ 4 mg/L) were investigated. High CRP patients displayed elevated circulating IL-1β, NETosis, and NET-associated TF plasma levels compared with low CRP ones. Additionally, analysis of patients stratified by circulating IL-1β levels yielded similar results. Moreover, NETosis and NET-associated TF plasma levels correlated positively in the whole population. In addition to the above, translational research experiments provided mechanistic confirmation for the clinical data identifying IL-1β as the initial trigger for the release of the pro-coagulant, NET-associated TF. In conclusion, blunted TF presentation by activated neutrophils undergoing NETosis may provide a mechanistic explanation to reduced secondary atherothrombotic events as observed in canakinumab-treated patients in CANTOS.

IL-1β and Statin Treatment in Patients with Myocardial Infarction and Diabetic Cardiomyopathy

Statins are effective lipid-lowering drugs with a good safety profile that have become, over the years, the first-line therapy for patients with dyslipidemia and a real cornerstone of cardiovascular (CV) preventive therapy. Thanks to both cholesterol-related and “pleiotropic” effects, statins have a beneficial impact against CV diseases. In particular, by reducing lipids and inflammation statins, they can influence the pathogenesis of both myocardial infarction and diabetic cardiomyopathy. Among inflammatory mediators involved in these diseases, interleukin (IL)-1β is a pro-inflammatory cytokine that recently been shown to be an effective target in secondary prevention of CV events. Statins are largely prescribed to patients with myocardial infarction and diabetes, but their effects on IL-1β synthesis and release remain to be fully characterized. Of interest, preliminary studies even report IL-1β secretion to rise after treatment with statins, with a potential impact on the inflammatory microenvironment and glycemic control. Here, we will summarize evidence of the role of statins in the prevention and treatment of myocardial infarction and diabetic cardiomyopathy. In accordance with the dual lipid-lowering and anti-inflammatory effect of these drugs and in light of the important results achieved by IL-1β inhibition through canakinumab in CV secondary prevention, we will dissect the current evidence linking statins with IL-1β and outline the possible benefits of a potential double treatment with statins and canakinumab.