Lymphocytes in atherosclerosis

Lymphocyte to White Blood Cell Count Ratio an Independent Risk Factor for Heart Failure

OBJECTIVE

Heart failure affects 1-2% of the population in developed countries. Hemogram biomarkers are cheap, rapid, readily accessible and are known to have prognostic benefit in cardiovascular, infectious and oncologic diseases.

METHODS

The aim of the current study is to evaluate lymphocyte-to-white-blood-cell ratio (LWR) as a prognostic predictor in patients with heart failure. Patients with heart failure were recruited between January 2000 and July 2001. Exclusion criteria included metastatic malignancy, exposure to chemotherapy, radiotherapy or medications known to affect complete blood count.

RESULTS

338 patients were enrolled, 33 were excluded. Mean age was 70.1 ± 10.8, 225 patients were male (73%) and 80 were female (27%). All patients were divided into three groups according to LWR. Group 1 < 0.2, group 2-0.2 < LWR < 0.35 and group 3 > 0.35. Patients with LWR ratio < 0.2 had the poorest survival while patients in the highest LWR (ratio > 0.35) had the best long-term survival.

CONCLUSIONS

Patients with congestive heart failure and LWR < 0.2 showed significant increased mortality. LWR was shown as independent prognostic predictor for HF patients compared to other main outcome parameters, including CRP, NYHA, EF and LDL.

The relationship between advanced lung cancer inflammation index and high SYNTAX score in patients with non-ST-elevation myocardial infarction

Introduction

The advanced lung cancer inflammation index (ALI) is an independent prognostic biomarker of inflammation and nutrition in various types of cancer, acute heart failure and acute coronary syndrome. The SYNTAX (Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery) score (SXscore) is an angiographic scoring tool used to determine the extent and severity of coronary artery disease.

Aim

To investigate the relationship between ALI and coronary artery lesion complexity assessed using the SXscore in patients with non-ST-segment elevation myocardial infarction (NSTEMI).

Material and methods

Between February and November 2020, a total of 284 patients with NSTEMI were included consecutively. ALI was calculated with the formula body mass index (BMI) × serum albumin concentration/neutrophil-to-lymphocyte ratio (NLR). SXscore was calculated using the online calculator and divided into two groups - low (< 32) and high (≥ 33) - and then analyzed.

Results

Patients with a high SXscore had lower ALI (22.4 ±7.3 vs. 58.5 ±44.3, p = 0.016). In the univariable analysis, age (p = 0.046), BMI (p = 0.021), C-reactive protein (p = 0.002), peak troponin I (p = 0.009), NLR (p = 0.025), serum albumin (p = 0.003) and ALI (p < 0.001) were significantly associated with a high SXscore. ALI emerged as an independent predictor of a high SXscore in multivariable analysis (95% CI: 0.931-0.984, p = 0.002).

Conclusions

The ALI may be useful as a simple tool for predicting high SXscore in patients with NSTEMI. To our knowledge, this is the first study to examine the relationship between ALI and severity of CAD.

Pathophysiological relevance and therapeutic outlook of GPR43 in atherosclerosis

Atherosclerosis (AS) is an inflammatory arterial disorder that occurs due to the deposition of the excessive lipoprotein under the artery intima, mainly including low-density lipoprotein and other apolipoprotein B-containing lipoproteins. G protein-coupled receptors (GPCRs) play a crucial role in transmitting signals in physiological and pathophysiological conditions. GPCRs recognize inflammatory mediators, thereby serving as important players during chronic inflammatory processes. It has been demonstrated that free fatty acids can function as ligands for various GPCRs, such as free fatty acid receptor (FFAR)1/GPR40, FFAR2/GPR43, FFAR3/GPR41, FFAR4/GPR120, and the lipid metabolite binding glucose-dependent insulinotropic receptor (GPR119). This review discusses GPR43 and its ligands in the pathogenesis of AS, especially focusing on its distinct role in regulating chronic vascular inflammation, inhibiting oxidative stress, ameliorating endothelial dysfunction and improving dyslipidemia. It is hoped that this review may provide guidance for further studies aimed at GPR43 as a promising target for drug development in the prevention and therapy of AS.

Oral Nanoformulations in Cardiovascular Medicine: Advances in Atherosclerosis Treatment

Atherosclerosis (AS) is the formation of atherosclerotic plaques on the walls of the arteries, causing them to narrow. If this occurs in the coronary arteries, the blood vessels may be completely blocked, resulting in myocardial infarction; if it occurs in the blood vessels of the brain, the blood vessels may be blocked, resulting in cerebral infarction, i.e., stroke. Studies have shown that the pathogenesis of atherosclerosis involves the processes of inflammation, lipid infiltration, oxidative stress, and endothelial damage, etc. SIRT, as a key factor regulating the molecular mechanisms of oxidative stress, inflammation, and aging, has an important impact on the pathogenesis of plaque formation, progression, and vulnerability. Statistics show that AS accounts for about 50 per cent of deaths in Western countries. Currently, oral medication is the mainstay of AS treatment, but its development is limited by side effects, low bioavailability and other unfavourable factors. In recent years, with the rapid development of nano-preparations, researchers have combined statins and natural product drugs within nanopreparations to improve their bioavailability. Based on this, this paper summarises the main pathogenesis of AS and also proposes new oral nanoformulations such as liposomes, nanoparticles, nanoemulsions, and nanocapsules to improve their application in the treatment of AS.

Association between extremely high prognostic nutritional index and all-cause mortality in patients with coronary artery disease: secondary analysis of a prospective cohort study in China

OBJECTIVES

Decreased prognostic nutritional index (PNI) was associated with adverse outcomes in many clinical diseases. This study aimed to evaluate the relationship between baseline PNI value and adverse clinical outcomes in patients with coronary artery disease (CAD).

DESIGN

The Personalized Antiplatelet Therapy According to CYP2C19 Genotype in Coronary Artery Disease (PRACTICE) study, a prospective cohort study of 15 250 patients with CAD, was performed from December 2016 to October 2021. The longest follow-up period was 5 years. This study was a secondary analysis of the PRACTICE study.

SETTING

The study setting was Xinjiang Medical University Affiliated First Hospital in China.

PARTICIPANTS

Using the 50th and 90th percentiles of the PNI in the total cohort as two cut-off limits, we divided all participants into three groups: Q1 (PNI <51.35, n = 7515), Q2 (51.35 ≤ PNI < 59.80, n = 5958) and Q3 (PNI ≥ 59.80, n = 1510). The PNI value was calculated as 10 × serum albumin (g/dL) + 0.005 × total lymphocyte count (per mm3).

PRIMARY OUTCOME

The primary outcome measure was mortality, including all-cause mortality (ACM) and cardiac mortality (CM).

RESULTS

In 14 983 participants followed for a median of 24 months, a total of 448 ACM, 333 CM, 1162 major adverse cardiovascular events (MACE) and 1276 major adverse cardiovascular and cerebrovascular events (MACCE) were recorded. The incidence of adverse outcomes was significantly different among the three groups (p <0.001). There were 338 (4.5%), 77 (1.3%) and 33 (2.2%) ACM events in the three groups, respectively. A restricted cubic spline displayed a J-shaped relationship between the PNI and worse 5-year outcomes, including ACM, CM, MACE and MACCE. After adjusting for traditional cardiovascular risk factors, we found that only patients with extremely high PNI values in the Q3 subgroup or low PNI values in the Q1 subgroup had a greater risk of ACM (Q3 vs Q2, HR: 1.617, 95% CI 1.012 to 2.585, p=0.045; Q1 vs Q2, HR=1.995, 95% CI 1.532 to 2.598, p <0.001).

CONCLUSION

This study revealed a J-shaped relationship between the baseline PNI and ACM in patients with CAD, with a greater risk of ACM at extremely high PNI values.

TRIAL REGISTRATION NUMBER

NCT05174143.

Exploring systemic inflammation in children with chronic kidney disease: correlates of interleukin 6

BACKGROUND

Systemic inflammation (SI) is linked to chronic kidney disease (CKD) progression and multiple complications. Data regarding SI biomarkers in pediatric patients are scarce. This case-control and cross-sectional study investigates the correlation of neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), total iron binding capacity (TIBC) and serum albumin to serum interleukin-6 (IL-6).

METHODS

NLR and PLR were measured in 53 patients (median age: 12.9 years), including 17 on dialysis and 36 with a median glomerular filtration rate of 39 ml/min/1.73m2, and in 25 age and sex-matched healthy controls. Iron profile, serum albumin and IL-6 were measured in the patient group. IL-6 levels > 3rd quartile were classified as high.

RESULTS

Patients presented higher NLR and PLR and particularly those on dialysis (p < 0.001 and p = 0.001). We observed a significant correlation between natural logarithm (ln) of IL-6 (lnIL-6) and NLR (rs = 0.344, p = 0.014), serum albumin (rs = -0.350, p = 0.011) and TIBC (rs = -0.345, p = 0.012) after adjustment for CKD stage, while the correlation between lnIL-6 and PLR was not significant (rs = 0.206, p = 0.151). Combination of NLR, serum albumin and TIBC predicted high IL-6 (13 patients) with an AUC of 0.771 (95% CI 0.608-0.943). Pairing of NLR ≥ 1.7 and TIBC ≤ 300 μg/dL exhibited the highest sensitivity (76.9%), while incorporating serum albumin ≤ 3.8 g/dL along with them achieved the highest specificity (95%) for detecting high IL-6 levels.

CONCLUSION

Both NLR and PLR levels increase in CKD, especially in patients on chronic dialysis. NLR, rather than PLR, along with TIBC and serum albumin, are associated with IL-6 in pediatric CKD.

Evolving concepts in the pathophysiology of atherosclerosis: from endothelial dysfunction to thrombus formation through multiple shades of inflammation

Atherosclerosis is the anatomo-pathological substrate of most cardio, cerebro and vascular diseases such as acute and chronic coronary syndromes, stroke and peripheral artery diseases. The pathophysiology of atherosclerotic plaque and its complications are under continuous investigation. In the last 2 decades our understanding on the formation, progression and complication of the atherosclerotic lesion has greatly improved and the role of immunity and inflammation is now well documented and accepted. The conventional risk factors modulate endothelial function determining the switch to a proatherosclerotic phenotype. From this point, lipid accumulation with an imbalance from cholesterol influx and efflux, foam cells formation, T-cell activation, cytokines release and matrix-degrading enzymes production occur. Lesions with high inflammatory rate become vulnerable and prone to rupture. Once complicated, the intraplaque thrombogenic material, such as the tissue factor, is exposed to the flowing blood, thus inducing coagulation cascade activation, platelets aggregation and finally intravascular thrombus formation that leads to clinical manifestations of this disease. Nonconventional risk factors, such as gut microbiome, are emerging novel markers of atherosclerosis. Several data indicate that gut microbiota may play a causative role in formation, progression and complication of atherosclerotic lesions. The gut dysbiosis-related inflammation and gut microbiota-derived metabolites have been proposed as the main working hypothesis in contributing to disease formation and progression. The current evidence suggest that the conventional and nonconventional risk factors may modulate the degree of inflammation of the atherosclerotic lesion, thus influencing its final fate. Based on this hypothesis, targeting inflammation seems to be a promising approach to further improve our management of atherosclerotic-related diseases.

Association of prognostic nutritional index level and diabetes status with the prognosis of coronary artery disease: a cohort study

BACKGROUND

Malnutrition and inflammation are associated with adverse clinical outcomes in patients with diabetes or coronary artery disease (CAD). Prognostic nutritional index (PNI) is a comprehensive and simple indicator reflecting nutritional condition and immunological status. Whether there is a crosstalk between nutritional-immunological status and diabetes status for the impact on the prognosis of coronary artery disease (CAD) is unclear.

METHODS

A total of 9429 consecutive CAD patients undergoing percutaneous coronary intervention were grouped by diabetes status [diabetes (DM) and non-diabetes (non-DM)] and preprocedural PNI level [high PNI (H-PNI) and low PNI (L-PNI)] categorized by the statistically optimal cut-off value of 48.49. The primary endpoint was all-cause death.

RESULTS

During a median follow-up of 5.1 years (interquartile range: 5.0-5.1 years), 366 patients died. Compared with the non-DM/H-PNI group, the DM/L-PNI group yielded the highest risk of all-cause death (adjusted hazard ratio: 2.65, 95% confidence interval: 1.97-3.56, p < 0.001), followed by the non-DM/L-PNI group (adjusted hazard ratio: 1.44, 95% confidence interval: 1.05-1.98, p = 0.026), while DM/H-PNI was not associated with the risk of all-cause death. The negative effect of L-PNI on all-cause death was significantly stronger in diabetic patients than in nondiabetic patients (p for interaction = 0.037). Preprocedural PNI category significantly improved the Global Registry of Acute Coronary Events (GRACE) risk score for predicting all-cause death in patients with acute coronary syndrome, especially in those with diabetes.

CONCLUSIONS

CAD patients with diabetes and L-PNI experienced the worst prognosis. The presence of diabetes amplifies the negative effect of L-PNI on all-cause death. Poor nutritional-immunological status outweighs diabetes in increasing the risk of all-cause death in CAD patients. Preprocedural PNI can serve as an assessment tool for nutritional and inflammatory risk and an independent prognostic factor in CAD patients, especially in those with diabetes.

PAX5/ITGAX Contributed to the Progression of Atherosclerosis by Regulation of B Differentiation via TNF-α Signaling Pathway

To investigate the effect of paired box protein 5 (PAX5)/integrin subunit alpha X (ITGAX) in atherosclerosis (AS). AS model was established using ApoE-/- mice (C57BL/6). Human vascular smooth muscle cells (HVSMCs) were stimulated with ox-LDL. Quantitative reverse transcription polymerase chain reaction and Western blotting were used to detect the expression levels of genes and proteins. Reporter constructs and luciferase assays were used to investigate the role of ITGAX and PAX5. Cells proliferation and inflammation factors were detected. The results presented that aortic plaque area, lipid content, serum triglyceride, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol levels were significantly increased in the high-fat diet group (p < 0.05). ITGAX was upregulated in atherosclerotic tissues. In addition, ox-LDL treatment induced HVSMCs proliferation, migration, and invasion. Reporter constructs and luciferase assays indicated ITGAX interaction with PAX5. Furthermore, siITGAX and siPAX5 cotransfection restored the rate of HVSMCs in G1 and S and G2/M phases, decreased the content of tumor necrosis factor-alpha (TNF-ɑ), interleukin (IL)-6, and IL-8 (p < 0.05). Interestingly, siITGAX and siPAX5 cotransfection also decreased the expression levels of TNF-α, TNF-R1, TNF-R2, CD19, and CD86 (p < 0.05). Our results suggest that ITGAX may be a potential therapeutic target for AS.

Colchicine in Athero-Thrombosis: Molecular Mechanisms and Clinical Evidence

Several lines of evidence have clearly indicated that inflammation plays a pivotal role in the development of atherosclerosis and of its thrombotic complications such as acute coronary syndromes or ischemic stroke. Thus, it has been postulated that the use of anti-inflammatory agents might be extremely useful to improve cardiovascular outcome. Recently, increasing attention has been reserved to one of the oldest plant-derived drugs still in use in clinical practice, colchicine that has been used as drug to treat inflammatory diseases such gout or Mediterranean fever. To date, current guidelines of the European Society of Cardiology have included colchicine as first line choice for treatment of acute and recurrent pericarditis. Moreover, several studies have investigated its role in the clinical scenarios of cardiovascular disease including chronic and acute coronary syndromes with promising results. In this review, starting from a description of the mechanism(s) involved behind its anti-inflammatory effects, we give an overview on its potential effects in atherothrombosis and finally present an updated overview of clinical evidence on the role of this drug in cardiovascular disease.

The relationship between nutrition and the immune system

Nutrition plays an essential role in the regulation of optimal immunological response, by providing adequate nutrients in sufficient concentrations to immune cells. There are a large number of micronutrients, such as minerals, and vitamins, as well as some macronutrients such as some amino acids, cholesterol and fatty acids demonstrated to exert a very important and specific impact on appropriate immune activity. This review aims to summarize at some extent the large amount of data accrued to date related to the modulation of immune function by certain micro and macronutrients and to emphasize their importance in maintaining human health. Thus, among many, some relevant case in point examples are brought and discussed: (1) The role of vitamin A/all-trans-retinoic-acids (ATRA) in acute promyelocytic leukemia, being this vitamin utilized as a very efficient therapeutic agent via effective modulation of the immune function (2) The involvement of vitamin C in the fight against tumor cells via the increase of the number of active NK cells. (3) The stimulation of apoptosis, the suppression of cancer cell proliferation, and delayed tumor development mediated by calcitriol/vitamin D by means of immunity regulation (4) The use of selenium as a cofactor to reach more effective immune response to COVID vaccination (5). The crucial role of cholesterol to regulate the immune function, which is demonstrated to be very sensitive to the variations of this macronutrient concentration. Other important examples are reviewed as well.

Microarray analysis reveals the potential molecular mechanism of Lp299v in stable coronary atherosclerotic disease

A growing body of evidence has confirmed that inflammatory mechanisms are involved in the formation and treatment of coronary atherosclerotic disease (CAD). An increase in circulatory levels of inflammatory cytokines has been found in patients with CAD, while the molecular mechanisms of inflammation still remain elusive. This study was designed to identify differentially expressed genes (DEGs), and to explore the molecular mechanism and hub genes that are involved in the effects of Lactobacillus plantarum 299v (Lp299v) supplementation. Microarray dataset (GSE156357) was downloaded from the Gene Expression Omnibus (GEO) database. The DEGs were identified by the R software. Then, the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses and construction of protein–protein interaction (PPI) network were performed by DAVID, STRING, and Cytoscape software. In daily alcohol user (DAU) group, 7,541 DEGs were identified, including 206 up-regulated and 7,335 down-regulated DEGs. In non-daily alcohol user (non-DAU) group, 2,799 DEGs were identified (2,491 up-regulated and 308 down-regulated DEGs). The GO enrichment analysis revealed that miosis was up-regulated and immune response was down-regulated. The KEGG enrichment analysis showed that Lp299v supplementation reduced the levels of chemotactic cytokines, and weakened immune response. Proteins of G protein-coupled receptor, inflammatory response, regulation of cell proliferation and apoptosis-related proteins were found in the PPI network. The hub genes were associated with G protein-coupled receptor, inflammatory response, and cell proliferation and apoptosis. The weighted gene co-expression network analysis (WGCNA) enriched the DEGs in 4 modules. This study indicated the expressions of chemokine receptors and regulation of immune response in the Lp299v supplementation. Meanwhile, it was supposed that chemokine receptors may have a cellular effect.

The mechanistic role of neutrophil lymphocyte ratio perturbations in the leading non communicable lifestyle diseases

Inflammation plays a critical role in the development and progression of chronic diseases like type 2 diabetes mellitus, coronary artery disease, and chronic obstructive pulmonary disease. Inflammatory responses are indispensable for pathogen control and tissue repair, but they also cause collateral damage. A chronically activated immune system and the resultant immune dysregulation mediated inflammatory surge may cause multiple negative effects, requiring tight regulation and dampening of the immune response to minimize host injury.  While chronic diseases are characterized by systemic inflammation, the mechanistic relationship of neutrophils and lymphocytes to inflammation and its correlation with the clinical outcomes is yet to be elucidated. The neutrophil to lymphocyte ratio (NLR) is an easy-to-measure laboratory marker used to assess systemic inflammation. Understanding the mechanisms of NLR perturbations in chronic diseases is crucial for risk stratification, early intervention, and finding novel therapeutic targets. We investigated the correlation between NLR and prevalent chronic conditions as a measure of systemic inflammation. In addition to predicting the risk of impending chronic conditions, NLR may also provide insight into their progression. This review summarizes the mechanisms of NLR perturbations at cellular and molecular levels, and the key inflammatory signaling pathways involved in the progression of chronic diseases. We have also explored preclinical studies investigating these pathways and the effect of quelling inflammation in chronic disease as reported by a few in vitro, in vivo studies, and clinical trials.

Turning Hot into Cold: Immune Microenvironment Reshaping for Atherosclerosis Attenuation Based on pH-Responsive shSiglec-1 Delivery System

Current atherosclerosis treatment is based on a combination of cholesterol-lowering medication and low-fat diets; however, the clinical effect is unsatisfactory. It has been shown that the level of immune cell infiltration and pro-inflammatory factors in the atherosclerotic immune microenvironment (AIM) play important roles in the development and progression of atherosclerosis. Therefore, we hypothesized that reshaping "hot AIM" into "cold AIM" could attenuate atherosclerosis. For this purpose, we designed a pH-responsive and charge-reversible nanosystem, referred to as Au-PEI/shSiglec-1/PEI-acetylsalicylic acid (ASPA NPs) to effectively deliver shSiglec-1, which blocked the interactions between macrophages with CD8⁺ T/NKT cells, thus inhibiting immune cell infiltration. Further, we demonstrated that acetylsalicylic acid (ASA), detached from the pH-responsive PEI-ASA polymer, and inhibited lipid accumulation in macrophage, thereby decreasing the lipid antigen presentation. Additionally, reduced macrophage-produced inflammatory factors by ASA and low CD8⁺ T/NKT cell infiltration levels synergistically inhibit Th17 cell differentiation, thus further dramatically attenuating inflammation in AIM by decreasing the IL-17A production. Eventually, ASPA NPs efficiently reshaped AIM by inhibiting immune cell infiltration, lipid antigen presentation, and pro-inflammation, which provided a feasible therapeutic strategy for atherosclerosis immunotherapy.

Pathophysiology and mechanisms of Acute Coronary Syndromes: athero-thrombosis, immune-inflammation and beyond

INTRODUCTION

The pathophysiology of atherosclerosis and its acute complications, such as the Acute Coronary Syndromes (ACS), is continuously under investigation. Immunity and inflammation seem to play a pivotal role in promoting formation and grow of atherosclerotic plaques. At the same time, plaque rupture followed by both platelets' activation and coagulation cascade induction lead to intracoronary thrombus formation. Although these phenomena might be considered responsible of about 90% of ACS, in up to 5-10% of acute syndromes a non-obstructive coronary artery disease (MINOCA) might be documented. This paper gives an overview on athero-thrombosis and immuno-inflammation processes involved in ACS pathophysiology also emphasizing the pathological mechanisms potentially involved in MINOCA.

AREAS COVERED

The relationship between immuno-inflammation and atherothrombosis is continuously updated by recent findings. At the same time, pathophysiology of MINOCA still remains a partially unexplored field, stimulating the research of potential links between these two aspects of ACS pathophysiology.

EXPERT OPINION

Pathophysyiology of ACS has been extensively investigated; however, several grey areas still remain. MINOCA represents one of these areas. At the same time, many aspects of immune-inflammation processes are still unknown. Thus, research should be continued to shed a brighter light on both these sides of "ACS" moon.

Neutrophil to lymphocyte ratio is not related to carotid atherosclerosis progression and cardiovascular events in the primary prevention of cardiovascular disease: Results from the IMPROVE study

Inflammation is a component of the pathogenesis of atherosclerosis and is associated with an increased risk of atherosclerotic cardiovascular disease (ASCVD). The neutrophil to lymphocyte ratio (NLR) is a possible inflammation metric for the detection of ASCVD risk, although results of prospective studies are highly inconsistent on this topic. We investigated the cross-sectional relationship between NLR and carotid intima-media thickness (cIMT) in subjects at moderate-to-high ASCVD risk. The prospective association between NLR, cIMT progression, and incident vascular events (VEs) was also explored. In 3341 subjects from the IMT-Progression as Predictors of VEs (IMPROVE) study, we analyzed the association between NLR, cIMT, and its 15-month progression. The association between NLR and incident VEs was also investigated. NLR was positively associated with cross-sectional measures of cIMT, but not with cIMT progression. The association between NLR and cross-sectional cIMT measures was abolished when adjusted for confounders. No association was found between NRL and incident VEs. Similarly, there were no significant differences in the hazard ratios (HRs) of VEs across NLR quartiles. NLR was neither associated with the presence and progression of carotid atherosclerosis, nor with the risk of VEs. Our findings do not support the role of NLR as a predictor of the risk of atherosclerosis progression and ASCVD events in subjects at moderate-to-high ASCVD risk, in primary prevention. However, the usefulness of NLR for patients at a different level of ASCVD risk cannot be inferred from this study.

Impact of Acute and Chronic Psychosocial Stress on Vascular Inflammation

Significance: Atherosclerosis and its complications, such as acute coronary syndromes, are the leading causes of death worldwide. A wide range of inflammatory processes substantially contribute to the initiation and progression of cardiovascular disease (CVD). In addition, epidemiological studies strongly associate both chronic stress and acute psychosocial stress with the occurrence of CVDs. Recent Advances: Extensive research during recent decades has not only identified major pathways in cardiovascular inflammation but also revealed a link between psychosocial factors and the immune system in the context of atherosclerosis. Both chronic and acute psychosocial stress drive systemic inflammation via neuroimmune interactions and promote atherosclerosis progression. Critical Issues: The associations human epidemiological studies found between psychosocial stress and cardiovascular inflammation have been substantiated by additional experimental studies in mice and humans. However, we do not yet fully understand the mechanisms through which psychosocial stress drives cardiovascular inflammation; consequently, specific treatment, although urgently needed, is lacking. Future Directions: Psychosocial factors are increasingly acknowledged as risk factors for CVD and are currently treated via behavioral interventions. Additional mechanistic insights might provide novel pharmacological treatment options to reduce stress-related morbidity and mortality. Antioxid. Redox Signal. 35, 1531-1550.

Lipid Droplets, the Central Hub Integrating Cell Metabolism and the Immune System

Lipid droplets (LDs) are commonly found in various biological cells and are organelles related to cell metabolism. LDs, the number and size of which are heterogeneous across cell type, are primarily composed of polar lipids and proteins on the surface with neutral lipids in the core. Neutral lipids stored in LDs can be degraded by lipolysis and lipophagocytosis, which are regulated by various proteins. The process of LD formation can be summarized in four steps. In addition to energy production, LDs play an extremely pivotal role in a variety of physiological and pathological processes, such as endoplasmic reticulum stress, lipid toxicity, storage of fat-soluble vitamins, regulation of oxidative stress, and reprogramming of cell metabolism. Interestingly, LDs, the hub of integration between metabolism and the immune system, are involved in antitumor immunity, anti-infective immunity (viruses, bacteria, parasites, etc.) and some metabolic immune diseases. Herein, we summarize the role of LDs in several major immune cells as elucidated in recent years, including T cells, dendritic cells, macrophages, mast cells, and neutrophils. Additionally, we analyze the role of the interaction between LDs and immune cells in two typical metabolic immune diseases: atherosclerosis and Mycobacterium tuberculosis infection.

Immunity in Atherosclerosis: Focusing on T and B Cells

Atherosclerosis is the major cause of the development of cardiovascular disease, which, in turn, is one of the leading causes of mortality worldwide. From the point of view of pathogenesis, atherosclerosis is an extremely complex disease. A huge variety of processes, such as violation of mitophagy, oxidative stress, damage to the endothelium, and others, are involved in atherogenesis; however, the main components of atherogenesis are considered to be inflammation and alterations of lipid metabolism. In this review, we want to focus on inflammation, and more specifically on the cellular elements of adaptive immunity, T and B cells. It is known that various T cells are widely represented directly in atherosclerotic plaques, while B cells can be found, for example, in the adventitia layer. Of course, such widespread and well-studied cells have attracted attention as potential therapeutic targets for the treatment of atherosclerosis. Various approaches have been developed and tested for their efficacy.

The roles of immune cells in atherosclerotic calcification

Atherosclerosis is the leading cause of acute cardiovascular events, and vascular calcification is an important pathological phenomenon in atherosclerosis. Recently, many studies have shown that immune cells are closely associated with the development of atherosclerosis and calcification, but there are many conflicting viewpoints because of immune system complications, such as the pro-atherosclerotic and atheroprotective effects of regulatory B cells (Bregs), T helper type 2 (Th2) cells and T helper type 17 (Th17) cells. In this review, we summarize the studies on the roles of immune cells, especially lymphocytes and macrophages, in atherosclerotic calcification. Furthermore, we prepared graphs showing the relationship between T cells, B cells and macrophages and atherosclerotic calcification. Finally, we highlight some potential issues that are closely associated with the function of immune cells in atherosclerotic calcification. Based on current research results, this review summarizes the relationship between immune cells and atherosclerotic calcification, and it will be beneficial to understand the relationship of immune cells and atherosclerotic calcification.

Chronic radiation exposure aggravates atherosclerosis by stimulating neutrophil infiltration

BACKGROUND

Radiation exposure is known to increase the risk of chronic inflammatory diseases, such as atherosclerosis, by modulating inflammation.

METHODS

To investigate the infiltration of leukocytes in radiation-aggravated atherosclerosis, we examined low-density lipoprotein receptor-deficient (Ldlr-/-) mice and C57BL/6j mice after exposure to 0.5 or 1 Gy radiation over 16 weeks.

RESULTS

We found that radiation exposure induced atherosclerosis development in Ldlr-/- mice, as demonstrated by increased lipid-laden plaque size, reactive oxygen species levels, and levels of the pro-inflammatory cytokines, IL-1β and TNF-α, in the aortas and spleens. Total plasma cholesterol, triglyceride, and LDL cholesterol levels were also increased by radiation exposure, along with cardiovascular risk. We also showed dose-dependent increases in neutrophils and monocytes that coincided with a reduction in lymphocytes in the spleens of Ldlr-/- mice. The correlation between the infiltration of leukocytes and cytokine production was also confirmed in the hearts and spleens of these mice.

CONCLUSIONS

We concluded that chronic radiation exposure increased the production of pro-inflammatory mediators, which was associated with the migration of neutrophils and inflammatory monocytes into sites of atherosclerosis. Thus, our data suggest that the accumulation of neutrophils and inflammatory monocytes, together with the reduction of lymphocytes, contribute to aggravated atherosclerosis in Ldlr-/- mice under prolonged exposure to radiation.

The Emerging Role of CT-Based Imaging in Adipose Tissue and Coronary Inflammation

A large body of evidence arising from recent randomized clinical trials demonstrate the association of vascular inflammatory mediators with coronary artery disease (CAD). Vascular inflammation localized in the coronary arteries leads to an increased risk of CAD-related events, and produces unique biological alterations to local cardiac adipose tissue depots. Coronary computed tomography angiography (CTA) provides a means of mapping inflammatory changes to both epicardial adipose tissue (EAT) and pericoronary adipose tissue (PCAT) as independent markers of coronary risk. Radiodensity or attenuation of PCAT on coronary CTA, notably, provides indirect quantification of coronary inflammation and is emerging as a promising non-invasive imaging implement. An increasing number of observational studies have shown robust associations between PCAT attenuation and major coronary events, including acute coronary syndrome, and 'vulnerable' atherosclerotic plaque phenotypes that are associated with an increased risk of the said events. This review outlines the biological characteristics of both EAT and PCAT and provides an overview of the current literature on PCAT attenuation as a surrogate marker of coronary inflammation.

Oral Unsaturated Fat Load Impairs Postprandial Systemic Inflammation in Primary Hypercholesterolemia Patients

Context: Primary hypercholesterolemia (PH) is a lipid disorder characterized by elevated levels of cholesterol and low-density lipoprotein (LDL). Low-grade systemic inflammation is associated with PH, which might explain the higher incidence of cardiovascular diseases in this setting.

Objective: To evaluate the effect of an oral unsaturated fat load (OUFL) on different immune parameters and functional consequences in patients with PH in postprandial state.

Design: A commercial liquid preparation of long-chain triglycerides (Supracal^®; ω6/ω3 ratio >20/1, OUFL) was administered to 20 patients and 10 age-matched controls. Whole blood was collected before (fasting state) and 4 h after administration (postprandial state). Flow cytometry was employed to determine platelet and leukocyte activation, and the levels of circulating platelet-leukocyte aggregates. Soluble markers were determined by ELISA, and the parallel-plate flow chamber was employed to study leukocyte adhesion to the dysfunctional arterial endothelium.

Results: The PH group had a lower percentage of activated platelets and circulating type 1 monocytes, and blunted neutrophil activation after the OUFL, accompanied by a significant increase in the percentage of regulatory T lymphocytes. In this group, the OUFL led to a significant impairment of leukocyte adhesion to the dysfunctional [tumor necrosis factor α (TNFα)-stimulated] endothelium and reduced the plasma levels of soluble P-selectin, platelet factor-4 (PF-4)/CXCL4, CXCL8, CCL2, CCL5, and TNFα.

Conclusion: The OUFL has a beneficial impact on the pro-thrombotic and pro-inflammatory state of PH patients and might be a promising macronutrient approach to dampen the systemic inflammation associated with PH and the development of further cardiovascular events.

Adaptive immune disorders in hypertension and heart failure: focusing on T-cell subset activation and clinical implications

: Hypertension is a growing health concern worldwide. Established hypertension is a causative factor of heart failure, which is characterized by increased vascular resistance and intractable uncontrolled blood pressure. Hypertension and heart failure have multiple causes and complex pathophysiology but cellular immunity is thought to contribute to the development of both. Recent studies showed that T cells play critical roles in hypertension and heart failure in humans and animals, with various stimuli leading to the formation of effector T cells that infiltrate the cardiovascular wall. Monocytes/macrophages also accumulate in the cardiovascular wall. Various cytokines (e.g. interleukin-6, interleukin-17, interleukin-10, tumor necrosis factor-α, and interferon-γ) released from immune cells of various subtypes promote vascular senescence and elastic laminal degradation as well as cardiac fibrosis and/or hypertrophy, leading to cardiovascular structural alterations and dysfunction. Recent laboratory evidence has defined a link between inflammation and the immune system in initiation and progression of hypertension and heart failure. Moreover, cross-talk among natural killer cells, adaptive immune cells (T cells and B cells), and innate immune cells (i.e. monocytes, macrophages, neutrophils, and dendritic cells) contributes to end-cardiovasculature damage and dysfunction in hypertension and heart failure. Clinical and experimental studies on the diagnostic potential of T-cell subsets revealed that blood regulatory T cells, CD4 cells, CD8 T cells, and the ratio of CD4 to CD8 T cells show promise as biomarkers of hypertension and heart failure. Therapeutic interventions to suppress activation of these cells may prove beneficial in reducing end-organ damage and preventing consequences of cardiovascular failure, including hypertension of heart failure.

Impact of Cholesterol Metabolism in Immune Cell Function and Atherosclerosis

Cholesterol, the most important sterol in mammals, helps maintain plasma membrane fluidity and is a precursor of bile acids, oxysterols, and steroid hormones. Cholesterol in the body is obtained from the diet or can be de novo synthetized. Cholesterol homeostasis is mainly regulated by the liver, where cholesterol is packed in lipoproteins for transport through a tightly regulated process. Changes in circulating lipoprotein cholesterol levels lead to atherosclerosis development, which is initiated by an accumulation of modified lipoproteins in the subendothelial space; this induces significant changes in immune cell differentiation and function. Beyond lesions, cholesterol levels also play important roles in immune cells such as monocyte priming, neutrophil activation, hematopoietic stem cell mobilization, and enhanced T cell production. In addition, changes in cholesterol intracellular metabolic enzymes or transporters in immune cells affect their signaling and phenotype differentiation, which can impact on atherosclerosis development. In this review, we describe the main regulatory pathways and mechanisms of cholesterol metabolism and how these affect immune cell generation, proliferation, activation, and signaling in the context of atherosclerosis.

Atherosclerosis as Pathogenetic Substrate for Sars-Cov2 Cytokine Storm

The severe acute respiratory syndrome coronavirus 2 (Sars-CoV-2) outbreak is a public health emergency affecting different regions around the world. The lungs are often damaged due to the presence of Sars-CoV-2 binding receptor ACE2 on epithelial alveolar cells. Severity of infection varies from complete absence of symptomatology to more aggressive symptoms, characterized by sudden acute respiratory distress syndrome (ARDS), multiorgan failure, and sepsis, requiring treatment in intensive care unit (ICU). It is not still clear why the immune system is not able to efficiently suppress viral replication in a small percentage of patients. It has been documented as pathological conditions affecting the cardiovascular system, strongly associated to atherosclerotic progression, such as heart failure (HF), coronary heart disease (CHD), hypertension (HTN) and diabetes mellitus (DM), could serve as predictive factors for severity and susceptibility during Sars-CoV-2 infection. Atherosclerotic progression, as a chronic inflammation process, is characterized by immune system dysregulation leading to pro-inflammatory patterns, including interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), and IL-1β. Reviewing immune system and inflammation profiles in atherosclerosis and laboratory results reported in severe COVID-19 infections, we hypothesized a pathogenetic correlation. Atherosclerosis may be an ideal pathogenetic substrate for high viral replication ability, leading to adverse outcomes, as reported in patients with cardiovascular factors. The level of atherosclerotic progression may affect a different degree of severe infection; in a vicious circle, feeding itself, Sars-CoV-2 may exacerbate atherosclerotic evolution due to excessive and aberrant plasmatic concentration of cytokines.

Modifiable Cardiovascular Risk, Hematopoiesis, and Innate Immunity

Unhealthy diet, lack of exercise, psychosocial stress, and insufficient sleep are increasingly prevalent modifiable risk factors for cardiovascular disease. Accumulating evidence indicates that these risk factors may fuel chronic inflammatory processes that are active in atherosclerosis and lead to myocardial infarction and stroke. In concert with hyperlipidemia, maladaptive immune system activities can contribute to disease progression and increase the probability of adverse events. In this review, we discuss recent insight into how the above modifiable risk factors influence innate immunity. Specifically, we focus on pathways that raise systemic myeloid cell numbers and modulate immune cell phenotypes, reviewing hematopoiesis, leukocyte trafficking, and innate immune cell accumulation in cardiovascular organs. Often, relevant mechanisms that begin with lifestyle choices and lead to cardiovascular events span multiple organ systems, including the central nervous, endocrine, metabolic, hematopoietic, immune and, finally, the cardiovascular system. We argue that deciphering such pathways provides not only support for preventive interventions but also opportunities to develop biomimetic immunomodulatory therapeutics that mitigate cardiovascular inflammation.

PD-1/PD-L1 in cardiovascular disease

The PD-1/PD-L1 coinhibitory pathway has critical roles in the immune response and autoimmunity via the regulation of T cell activity. Excessive activity and high expression of this pathway suppresses the function of T cells and immunity. Recent research has indicated that tumour cells express high levels of PD-L1, which has an immunosuppressive effect and can result in treatment failure. Anti-PD-L1 or anti-PD-1 agents have well-established beneficial effects on mortality and quality of life in cancer patients. Based on the regulatory effects and therapeutic value of the PD-1/PD-L1 pathway in malignant disorders, we propose that it also regulates cell immunity and in CHD and atherosclerosis. Low expression level of PD-1/ PD-L1 or anti-PD-1/PD-L1 therapy accelerates the immune processes in CHD and aggravates disease according to numerous studies. A few studies have provided strong evidence that changes in the expression levels of PD-1 or PD-L1 can alter the degree of inflammation and the state of coronary plaques in atherosclerosis. In this review, we summarise the alterations of the PD-1/PD-L1 pathway and discuss its role in CHD.

B Cell and CD4 T Cell Interactions Promote Development of Atherosclerosis

Interaction between B and CD4 T cells is crucial for their optimal responses in adaptive immunity. Immune responses augmented by their partnership promote chronic inflammation. Here we report that interaction between B and CD4 T cells augments their atherogenicity to promote lipid-induced atherosclerosis. Genetic deletion of the gene encoding immunoglobulin mu (μ) heavy chain (μMT) in ApoE^−/− mice resulted in global loss of B cells including those in atherosclerotic plaques, undetectable immunoglobulins and impaired germinal center formation. Despite unaffected numbers in the circulation and peripheral lymph nodes, CD4 T cells were also reduced in spleens as were activated and memory CD4 T cells. In hyperlipidemic μMT^−/− ApoE^−/− mice, B cell deficiency decreased atherosclerotic lesions, accompanied by absence of immunoglobulins and reduced CD4 T cell accumulation in lesions. Adoptive transfer of B cells deficient in either MHCII or co-stimulatory molecule CD40, molecules required for B and CD4 T cell interaction, into B cell-deficient μMT^−/− ApoE^−/− mice failed to increase atherosclerosis. In contrast, wildtype B cells transferred into μMT^−/− ApoE^−/− mice increased atherosclerosis and increased CD4 T cells in lesions including activated and memory CD4 T cells. Transferred B cells also increased their expression of atherogenic cytokines IL-1β, TGF-β, MCP-1, M-CSF, and MIF, with partial restoration of germinal centers and plasma immunoglobulins. Our study demonstrates that interaction between B and CD4 T cells utilizing MHCII and CD40 is essential to augment their function to increase atherosclerosis in hyperlipidemic mice. These findings suggest that targeting B cell and CD4 T cell interaction may be a therapeutic strategy to limit atherosclerosis progression.

Signs of Deregulated Gene Expression Are Present in Both CD14+ and CD14- PBMC From Non-Obese Men With Family History of T2DM

AIM

Development of type 2 diabetes (T2DM) is associated with disturbances in immune and metabolic status that may be reflected by an altered gene expression profile of peripheral blood mononuclear cells (PBMC). To reveal a potential family predisposition to these alterations, we investigated the regulation of gene expression profiles in circulating CD14⁺ and CD14^- PBMC in fasting conditions and in response to oral glucose tolerance test (OGTT) in glucose tolerant first-degree relatives (FDR) of T2DM patients and in control subjects.

MATERIALS AND METHODS

This work is based on the clinical study LIMEX (NCT03155412). Non-obese 12 non-diabetic (FDR), and 12 control men without family history of diabetes matched for age and BMI underwent OGTT. Blood samples taken before and at the end of OGTT were used for isolation of circulating CD14⁺ and CD14^- PBMC. In these cells, mRNA levels of 94 genes related to lipid and carbohydrate metabolism, immunity, and inflammation were assessed by qPCR.

RESULTS

Irrespectively of the group, the majority of analyzed genes had different mRNA expression in CD14⁺ PBMC compared to CD14^- PBMC in the basal (fasting) condition. Seven genes (IRS1, TLR2, TNFα in CD14⁺ PBMC; ABCA1, ACOX1, ATGL, IL6 in CD14^- PBMC) had different expression in control vs. FDR groups. OGTT regulated mRNA levels of nine genes selectively in CD14⁺ PBMC and of two genes (ABCA1, PFKL) selectively in CD14^-PBMC. Differences in OGTT-induced response between FDR and controls were observed for EGR2, CCL2 in CD14⁺ PBMC and for ABCA1, ACOX1, DGAT2, MLCYD, and PTGS2 in CD14^- PBMC.

CONCLUSION

This study revealed a different impact of glucose challenge on gene expression in CD14⁺ when compared with CD14^- PBMC fractions and suggested possible impact of family predisposition to T2DM on basal and OGTT-induced gene expression in these PBMC fractions. Future studies on these putative alterations of inflammation and lipid metabolism in fractionated PBMC in larger groups of subjects are warranted.

Predictive Value of Hematologic Indices in the Diagnosis of Acute Coronary Syndrome

BACKGROUND

Distinguishing between Acute Coronary Syndrom (ACS) and SCAD (Stable Coronary Artery Disease) requires advanced laboratory instrument and electrocardiogram. However, their availabilities in primary care settings in developing countries are limited. Hematologic changes usually occur in the ACS patient and might be valuable to distinguish ACS from SCAD.

AIM

This study compares the hematologic indices between ACS and SCAD patients and analyses its predictive value for ACS.

MATERIAL AND METHODS

A total of 191 patients (79 ACS and 112 SCAD) were enrolled in this study based on the inclusion criteria. Patient's characteristic, hematologic indices on admission, and the final diagnosis were obtained from medical records. Statistical analyses were done using SPSS 23.0.

RESULTS

In this research MCHC value (33.40 vs. 32.80 g/dL; p < 0.05); WBC (11.16 vs. 7.40 x109/L; p < 0.001); NLR (6.29 vs. 2.18; p < 0.001); and PLR (173.88 vs 122.46; p < 0.001) were significantly higher in ACS compared to SCAD patients. While MPV (6.40 vs. 10.00 fL; p < 0.001) was significantly lower in ACS patients. ROC curve analysis showed MPV had the highest AUC (95%) for ACS diagnosis with an optimum cut-off point at ≤ 8.35 fL (sensitivity 93.6% and specificity 97.3%).

CONCLUSION

There was a significant difference between hematologic indices between ACS and SCAD patients. MPV is the best indices to distinguish ACS.

Type 1 diabetic mellitus patients with increased atherosclerosis risk display decreased CDKN2A/2B/2BAS gene expression in leukocytes

Background

Type 1 diabetes mellitus (T1DM) patients display increased risk of cardiovascular disease (CVD) and are characterized by a diminished regulatory T (Treg) cell content or function. Previous studies have shown an association between decreased CDKN2A/2B/2BAS gene expression and enhanced CVD. In the present study the potential relationship between CDKN2A/2B/2BAS gene expression, immune cell dysfunction and increased cardiovascular risk in T1DM patients was explored.

Methods

A cross-sectional study was performed in 90 subjects divided into controls and T1DM patients. Circulating leukocyte subpopulations analysis by flow cytometry, expression studies on peripheral blood mononuclear cell by qPCR and western blot and correlation studies were performed in both groups of subjects.

Results

Analysis indicated that, consistent with the described T cell dysfunction, T1DM subjects showed decreased circulating CD4+CD25+CD127− Treg cells. In addition, T1DM subjects had lower mRNA levels of the transcription factors FOXP3 and RORC and lower levels of IL2 and IL6 which are involved in Treg and Th17 cell differentiation, respectively. T1DM patients also exhibited decreased mRNA levels of CDKN2A (variant 1 p16^Ink4a), CDKN2A (p14^Arf,variant 4), CDKN2B (p15^Ink4b) and CDKN2BAS compared with controls. Notably, T1DM patients had augmented pro-atherogenic CD14++CD16+-monocytes, which predict cardiovascular acute events and enhanced common carotid intima-media thickness (CC-IMT).

Conclusions

Decreased expression of CDKN2A/2B/2BAS in leukocytes associates with increased CC-IMT atherosclerosis surrogate marker and proatherogenic CD14++CD16+ monocytes in T1DM patients. These results suggest a potential role of CDKN2A/2B/2BAS genes in CVD risk in T1DM.

Electronic supplementary material

The online version of this article (10.1186/s12967-019-1977-1) contains supplementary material, which is available to authorized users.

Gender-specific association between neutrophil-to-lymphocyte ratio and arterial stiffness in an apparently healthy population undergoing a health examination

Objective

Neutrophil-to-lymphocyte ratio (NLR) value has emerged as a cardiovascular prognostic marker. Although several recent studies suggested NLR was associated with arterial stiffness, it was still controversial. The aim of this study was to investigate the correlation between NLR and arterial stiffness by measuring of brachial-ankle pulse wave velocity (baPWV) in an apparently healthy population.

Methods

This retrospective study enrolled 5612 participants during the health examinations from 1 October 2007 to 30 September 2011. Arterial stiffness was measured by baPWV. NLR was calculated as the ratio of the absolute neutrophil count to the absolute lymphocyte count in peripheral blood. According to the quartiles of NLR, the patients were categorized into four groups in males and females, respectively. Associations between NLR and baPWV were evaluated using partial correlation and multivariate logistic regression analysis.

Results

Both female and male subjects with increased arterial stiffness (baPWV ≥ 1400 cm/s) were likely to be older (females: P < 0.001, males: P < 0.001) and have higher systolic blood pressure (females: P < 0.001, males: P < 0.001), diastolic blood pressure (females: P < 0.001, males: P < 0.001), fasting plasma glucose (females: P < 0.001, males: P < 0.001), serum total cholesterol (females: P < 0.001, males: P = 0.028), triglyceride (females: P < 0.001, males: P = 0.031), urea nitrogen (females: P < 0.001, males: P < 0.001) than those without increased arterial stiffness. In addition, compared to those without increased arterial stiffness, body mass index ( P < 0.001), waist circumference ( P < 0.001), low-density lipoproteins cholesterol ( P < 0.001), creatinine ( P < 0.001), uric acid ( P < 0.001) and lymphocytes ( P = 0.001) were higher in females with increased arterial stiffness. However, males with increased arterial stiffness had higher NLR value (2.0 ± 0.7 vs. 2.1 ± 0.9, P < 0.001) and neutrophils (4.3 ± 1.4 vs. 4.5 ± 1.5, P < 0.001) than those without increased arterial stiffness, while the difference was not found in females. ANCOVA showed that males with quartile 3 and quartile 4 of NLR had greater levels of baPWV. NLR was correlated to baPWV in males by partial correlation analysis (r = 0.110, P < 0.001), but not in females. In multiple logistic regression analysis, the quartile 4 of NLR was positively associated with increased arterial stiffness in males (OR = 1.43, 95% confidence intervals [CI]=1.12–1.82, P = 0.004), but there was no obvious correlation in females.

Conclusions

Our findings suggest that there is a gender difference in the relationship between arterial stiffness and NLR. After adjusting for other confounders, the risk of increased arterial stiffness in apparently healthy adult males (rather than females) is independently associated with the highest quartile of NLR.

Atherosclerosis Treatment with Stimuli-Responsive Nanoagents: Recent Advances and Future Perspectives

Atherosclerosis is the root of approximately one-third of global mortalities. Nanotechnology exhibits splendid prospects to combat atherosclerosis at the molecular level by engineering smart nanoagents with versatile functionalizations. Significant advances in nanoengineering enable nanoagents to autonomously navigate in the bloodstream, escape from biological barriers, and assemble with their nanocohort at the targeted lesion. The assembly of nanoagents with endogenous and exogenous stimuli breaks down their shells, facilitates intracellular delivery, releases their cargo to kill the corrupt cells, and gives imaging reports. All these improvements pave the way toward personalized medicine for atherosclerosis. This review systematically summarizes the recent advances in stimuli-responsive nanoagents for atherosclerosis management and its progress in clinical trials.

Immune Disorder in Atherosclerotic Cardiovascular Disease - Clinical Implications of Using Circulating T-Cell Subsets as Biomarkers

Atherosclerotic cardiovascular disease (ACVD) is an inflammatory phenomenon that leads to structural abnormality in the vascular lumen due to the formation of atheroma by the deposition of lipid particles and inflammatory cytokines. There is a close interaction between innate immune cells (neutrophils, monocyte, macrophages, dendritic cells) and adaptive immune cells (T and B lymphocytes) in the initiation and progression of atherosclerosis. According to novel insights into the role of adaptive immunity in atherosclerosis, the activation of CD4⁺T cells in response to oxidized low-density lipoprotein-antigen initiates the formation and facilitates the propagation of atheroma, whereas CD8⁺T cells cause the rupture of a developed atheroma by their cytotoxic nature. Peripheral CD4⁺and CD8⁺T-cell counts were altered in patients with other cardiovascular risk factors. Furthermore, on evaluation of the feasibility of immune cells as a diagnostic tool, the blood CD4⁺(helper), CD8⁺(cytotoxic), and CD4⁺CD25⁺Foxp3⁺(regulatory) T cells and the ratio of CD4 to CD8 cells hold promise as biomarkers of coronary artery disease and their subtypes. T cells also could be a therapeutic target for cardiovascular diseases. The goal of this review was therefore to summarize the available information regarding immune disorders in ACVD with a special focus on the clinical implications of circulating T-cell subsets as biomarkers.

Changes in CDKN2A/2B expression associate with T-cell phenotype modulation in atherosclerosis and type 2 diabetes mellitus

Previous studies indicate a role of CDKN2A/2B/2BAS genes in atherosclerosis and type 2 diabetes mellitus (T2DM). Progression of these diseases is accompanied by T-cell imbalance and chronic inflammation. Our main objective was to investigate a potential association between CDKN2A/2B/2BAS gene expression and T cell phenotype in T2DM and coronary artery disease (CAD) in humans, and to explore the therapeutic potential of these genes to restore immune cell homeostasis and disease progression. Reduced mRNA levels of CDKN2A (p16^Ink4a), CDKN2B (p15^Ink4b), and CDKN2BAS were observed in human T2DM and T2DM-CAD subjects compared with controls. Protein levels of p16^Ink4a and p15^Ink4b were also diminished in T2DM-CAD patients while CDK4 levels, the main target of p16^Ink4a and p15^Ink4b, were augmented in T2DM and T2DM-CAD subjects. Both patient groups displayed higher activated CD3+CD69+ T cells and proatherogenic CD14++CD16+ monocytes, while CD4+CD25+CD127 regulatory T (Treg cells) cells were decreased. Treatment of primary human lymphocytes with PD0332991, a p16^Ink4a/p15^Ink4b mimetic drug and a proven CDK4 inhibitor, increased Treg cells and the levels of activated transcription factor phosphoSTAT5. In vivo PD0332991 treatment of atherosclerotic apoE-/- mice and insulin resistant apoE-/-Irs2+/- mice augmented Foxp3-expressing Treg cells and decreased lesion size. Thus, atherosclerosis complications in T2DM associate with altered immune cell homeostasis, diminished CDKN2A/2B/2BAS expression, and increased CDK4 levels. The present study also suggests that the treatment with drugs that mimic CDKN2A/2B genes could potential be considered as a promising therapy to delay atherosclerosis.

Discovery, synthesis and anti-atherosclerotic activities of a novel selective sphingomyelin synthase 2 inhibitor

The sphingomyelin synthase 2 (SMS2) is a potential target for pharmacological intervention in atherosclerosis. However, so far, few selective SMS2 inhibitors and their pharmacological activities were reported. In this study, a class of 2-benzyloxybenzamides were discovered as novel SMS2 inhibitors through scaffold hopping and structural optimization. Among them, Ly93 as one of the most potent inhibitors exhibited IC₅₀ values of 91 nM and 133.9 μM against purified SMS2 and SMS1 respectively. The selectivity ratio of Ly93 was more than 1400-fold for purified SMS2 over SMS1. The in vitro studies indicated that Ly93 not only dose-dependently diminished apoB secretion from Huh7 cells, but also significantly reduced the SMS activity and increased cholesterol efflux from macrophages. Meanwhile, Ly93 inhibited the secretion of LPS-mediated pro-inflammatory cytokine and chemokine in macrophages. The pharmacokinetic profiles of Ly93 performed on C57BL/6J mice demonstrated that Ly93 was orally efficacious. As a potent selective SMS2 inhibitor, Ly93 significantly decreased the plasma SM levels of C57BL/6J mice. Furthermore, Ly93 was capable of dose-dependently attenuating the atherosclerotic lesions in the root and the entire aorta as well as macrophage content in lesions, in apolipoprotein E gene knockout mice treated with Ly93. In conclusion, we discovered a novel selective SMS2 inhibitor Ly93 and demonstrated its anti-atherosclerotic activities in vivo. The preliminary molecular mechanism-of-action studies revealed its function in lipid homeostasis and inflammation process, which indicated that the selective inhibition of SMS2 would be a promising treatment for atherosclerosis.

The effects of pigment epithelium-derived factor on atherosclerosis: putative mechanisms of the process

Cardiovascular disease (CVD) is a leading cause of death worldwide. Atherosclerosis is believed to be the major cause of CVD, characterized by atherosclerotic lesion formation and plaque disruption. Although remarkable advances in understanding the mechanisms of atherosclerosis have been made, the application of these theories is still limited in the prevention and treatment of atherosclerosis. Therefore, novel and effective strategies to treat high-risk patients with atherosclerosis require further development. Pigment epithelium-derived factor (PEDF), a glycoprotein with anti-inflammatory, anti-oxidant, anti-angiogenic, anti-thrombotic and anti-tumorigenic properties, is of considerable interest in the prevention of atherosclerosis. Accumulating research has suggested that PEDF exerts beneficial effects on atherosclerotic lesions and CVD patients. Our group, along with colleagues, has demonstrated that PEDF may be associated with acute coronary syndrome (ACS), and that the polymorphisms of rs8075977 of PEDF are correlated with coronary artery disease (CAD). Moreover, we have explored the anti-atherosclerosis mechanisms of PEDF, showing that oxidized-low density lipoprotein (ox-LDL) reduced PEDF concentrations through the upregulation of reactive oxygen species (ROS), and that D-4F can protect endothelial cells against ox-LDL-induced injury by preventing the downregulation of PEDF. Additionally, PEDF might alleviate endothelial injury by inhibiting the Wnt/β-catenin pathway. These data suggest that PEDF may be a novel therapeutic target for the treatment of atherosclerosis. In this review, we will summarize the role of PEDF in the development of atherosclerosis, focusing on endothelial dysfunction, inflammation, oxidative stress, angiogenesis and cell proliferation. We will also discuss its promising therapeutic implications for atherosclerosis.

Fibroblast growth factor-transforming growth factor beta dialogues, endothelial cell to mesenchymal transition, and atherosclerosis

PURPOSE OF REVIEW

Despite much effort, atherosclerosis remains an important public health problem, leading to substantial morbidity and mortality worldwide. The purpose of this review is to provide an understanding of the role of endothelial cell fate change in atherosclerosis process.

RECENT FINDINGS

Recent studies indicate that a process known as endothelial-to-mesenchymal transition (EndMT) may play an important role in atherosclerosis development. Transforming growth factor beta (TGFβ) has been shown to be an important driver of the endothelial cell phenotype transition.

SUMMARY

The current review deals with the current state of knowledge regarding EndMT's role in atherosclerosis and its regulation by fibroblast growth factor (FGF)-TGFβ cross-talk. A better understanding of FGF-TGFβ signaling in the regulation of endothelial cell phenotypes is key to the development of novel therapeutic agents.

Follicular regulatory T cell in atherosclerosis

Atherosclerosis is a chronic inflammatory disease involving the infiltration of immune cells, such as monocytes/macrophages, neutrophils, T cells, and B cells, into the inner layer of vessel walls. T and B cell functions in the process of atherogenesis, as well as their mutual regulation, have been investigated but several aspects remain to be clarified. In the present review, we give a brief overview of the functions of follicular regulatory T cell (Tfr) on follicular T (Tfh) and B cell regulation related to atherosclerosis pathogenesis, including their influence on lymphangiogenesis and lipoprotein metabolism. We will also discuss their potential therapeutics properties in the resolution of established atherosclerotic lesions.

Understanding the Impact of Dietary Cholesterol on Chronic Metabolic Diseases through Studies in Rodent Models

The development of certain chronic metabolic diseases has been attributed to elevated levels of dietary cholesterol. However, decades of research in animal models and humans have demonstrated a high complexity with respect to the impact of dietary cholesterol on the progression of these diseases. Thus, recent investigations in non-alcoholic fatty liver disease (NAFLD) point to dietary cholesterol as a key factor for the activation of inflammatory pathways underlying the transition from NAFLD to non-alcoholic steatohepatitis (NASH) and to hepatic carcinoma. Dietary cholesterol was initially thought to be the key factor for cardiovascular disease development, but its impact on the disease depends partly on the capacity to modulate plasmatic circulating low-density lipoprotein (LDL) cholesterol levels. These studies evidence a complex relationship between these chronic metabolic diseases and dietary cholesterol, which, in certain conditions, might promote metabolic complications. In this review, we summarize rodent studies that evaluate the impact of dietary cholesterol on these two prevalent chronic diseases and their relevance to human pathology.