Platelet activating factor: A potential biomarker in acute coronary syndrome?

Genetic Markers of Cardiovascular Disease

Cardiovascular Disorders (CVDs) are the leading cause mortality in developed as well as developing nations, and has now emerged as one of the leading causes of disability and mortality around the globe. According to the World Health Organization, four out of every five patients with cardiovascular disease die from a myocardial infarction each year. Numerous genes have been linked to coronary artery disease, influencing mechanisms such as blood pressure regulation, lipid metabolism, inflammation, and cardiac activity. Genetic variations or mutations in these genes can affect lipid metabolism, blood pressure management, and heart function, increasing the risk of obesity, metabolic disorders, and resulting in the development of cardiovascular disease. Understanding the role of genes and related complications are essential for the identification, management, and prevention of cardiovascular conditions. Performing a genetic test for variations in the gene may help identify people as well as their families who are at a greater risk of heart disease, which enables risk identification and timely intervention. . This article investigates the applications of genetic biomarkers in cardiac disorders such as coronary artery disease, hypertension, arrhythmias, cardiomyopathy, and heart failure, with an emphasis on individual genes and their effects on mutation.

Role of Platelet Activating Factor as a Mediator of Inflammatory Diseases and Preterm Delivery

Nearly 70% of preterm deliveries occur spontaneously, and the clinical pathways involved include preterm labor and preterm premature rupture of membranes. Prediction of preterm delivery is considered crucial due to the significant effects of preterm birth on health and the economy at both the personal and community levels. Although similar inflammatory processes occur in both term and preterm delivery, the premature activation of these processes or exaggerated inflammatory response triggered by infection or sterile factors leads to preterm delivery. Platelet activating factor (PAF) is a phosphoglycerylether lipid mediator of inflammation that is implicated in infections, cancers, and various chronic diseases and disorders including cardiovascular, renal, cerebrovascular, and central nervous system diseases. In gestational tissues, PAF mediates the inflammatory pathways that stimulate the effector mechanisms of labor, including myometrial contraction, cervical dilation, and fetal membrane rupture. Women with preterm labor and preterm premature rupture of membranes have increased levels of PAF in their amniotic fluid. In mice, the intrauterine or intraperitoneal administration of carbamyl PAF activates inflammation in gestational tissues, thereby eliciting preterm delivery. This review summarizes recent research on PAF as an important inflammatory mediator in preterm delivery and in other inflammatory disorders, highlighting its potential value for prediction, intervention, and prevention of these diseases.

Targeting the High-Density Lipoprotein Proteome for the Treatment of Post-Acute Sequelae of SARS-CoV-2

Here, we target the high-density lipoprotein (HDL) proteome in a case series of 16 patients with post-COVID-19 symptoms treated with HMG-Co-A reductase inhibitors (statin) plus angiotensin II type 1 receptor blockers (ARBs) for 6 weeks. Patients suffering from persistent symptoms (post-acute sequelae) after serologically confirmed SARS-CoV-2 infection (post-COVID-19 syndrome, PCS, n = 8) or following SARS-CoV-2 vaccination (PVS, n = 8) were included. Asymptomatic subjects with corresponding serological findings served as healthy controls (n = 8/8). HDL was isolated using dextran sulfate precipitation and the HDL proteome of all study participants was analyzed quantitatively by mass spectrometry. Clinical symptoms were assessed using questionnaires before and after therapy. The inflammatory potential of the patients' HDL proteome was addressed in human endothelial cells. The HDL proteome of patients with PCS and PVS showed no significant differences; however, compared to controls, the HDL from PVS/PCS patients displayed significant alterations involving hemoglobin, cytoskeletal proteins (MYL6, TLN1, PARVB, TPM4, FLNA), and amyloid precursor protein. Gene Ontology Biological Process (GOBP) enrichment analysis identified hemostasis, peptidase, and lipoprotein regulation pathways to be involved. Treatment of PVS/PCS patients with statins plus ARBs improved the patients' clinical symptoms. After therapy, three proteins were significantly increased (FAM3C, AT6AP2, ADAM10; FDR < 0.05) in the HDL proteome from patients with PVS/PCS. Exposure of human endothelial cells with the HDL proteome from treated PVS/PCS patients revealed reduced inflammatory cytokine and adhesion molecule expression. Thus, HDL proteome analysis from PVS/PCS patients enables a deeper insight into the underlying disease mechanisms, pointing to significant involvement in metabolic and signaling disturbances. Treatment with statins plus ARBs improved clinical symptoms and reduced the inflammatory potential of the HDL proteome. These observations may guide future therapeutic strategies for PVS/PCS patients.

Interplay of inflammatory biomarkers in heart disease patients with depressive symptoms: An update

The pathophysiological mechanisms that connect heart disease and depressive disorders have been identified as abnormal endothelial function, dysregulation of the Hypothalamic Pituitary Adrenal (HPA) axis and abnormal platelet activities. Among these mechanisms, both endothelial dysfunction and HPA axis dysregulation are influenced by low grade inflammation and play significant roles in both conditions. Consequently, it is hypothesized that inflammation is an integral part of the formation of atherosclerotic plaques, linking the occurrence of heart diseases to the activation and shedding of intercellular adhesion molecules (ICAMs), especially soluble ICAM-1. This process is accompanied by the local and systemic secretion of various inflammatory markers like interleukin-6, Tumour Necrosis Factor, and C-reactive protein. Therefore, this review primarily focuses on defining the potential role of different inflammatory biomarkers in depression and heart disease and assessing whether mediators could serve as predictive biomarkers for detecting depressive symptoms in patients with heart disease.

Associations between healthy food groups and platelet-activating factor, lipoprotein-associated phospholipase A2 and C-reactive protein: a cross-sectional study

PURPOSE

To investigate the association between pro-inflammatory markers platelet-activating factor (PAF), lipoprotein-associated phospholipase A2 (Lp-PLA2), hsCRP, and intake of core food groups including fruit, cruciferous and other vegetables, grains, meat and poultry, fish and seafood, nuts and legumes, and dairy.

METHODS

A cross-sectional study was conducted. 100 adults (49 ± 13 years, 31% male) with variable cardiovascular disease risk were recruited. Data were collected in 2021 and 2022. Fasting PAF, Lp-PLA2 activity, hsCRP and usual dietary intake (via a validated food frequency questionnaire) were measured. Intake of foods were converted into serves and classified into food groups. Correlations and multiple regressions were performed with adjustment for confounders.

RESULTS

A one-serve increase in cruciferous vegetables per day was associated with 20-24% lower PAF levels. An increase of one serve per day of nuts and legumes was associated with 40% lower hsCRP levels. There were small correlations with PAF and Lp-PLA2 and cheese, however, these were not significant at the Bonferroni-adjusted P < 0.005 level.

CONCLUSION

The lack of associations between PAF and Lp-PLA2 and other healthy foods may be due to confounding by COVID-19 infection and vaccination programs which prevents any firm conclusion on the relationship between PAF, Lp-PLA2 and food groups. Future research should aim to examine the relationship with these novel markers and healthy food groups in a non-pandemic setting.

Cardiovascular Diseases and Marine Oils: A Focus on Omega-3 Polyunsaturated Fatty Acids and Polar Lipids

Cardiovascular diseases (CVD) remain the leading cause of death across the globe, hence, establishing strategies to counteract CVD are imperative to reduce mortality and the burden on health systems. Dietary modification is an effective primary prevention strategy against CVD. Research regarding dietary supplementation has become increasingly popular. This review focuses on the current in vivo, in vitro, and epidemiological studies associated with that of omega-3 polyunsaturated fatty acids (n-3 PUFAs) and polar lipids (PLs) and how they play a role against CVD. Furthermore, this review focuses on the results of several major clinical trials examining n-3 PUFAs regarding both primary and secondary prevention of CVD. Notably, we place a lens on the REDUCE-IT and STRENGTH trials. Finally, supplementation of PLs has recently been suggested as a potential alternative avenue for the reduction of CVD incidence versus neutral forms of n-3 PUFAs. However, the clinical evidence for this argument is currently rather limited. Therefore, we draw on the current literature to suggest future clinical trials for PL supplementation. We conclude that despite conflicting evidence, future human trials must be completed to confirm whether PL supplementation may be more effective than n-3 PUFA supplementation to reduce cardiovascular risk.

Role of simple inflammatory parameters in predicting the severity of coronary artery disease

OBJECTIVE

In our study, we aimed to find simple, useful biomarkers in patients with non-ST elevation myocardial infarction to predict coronary artery severity.

METHODS

Between May 2022 and December 2022, patients diagnosed with non-ST elevation myocardial infarction according to the European cardiology guidelines were included in our study. The Synergy between PCI with Taxus and Cardiac Surgery score was calculated to determine the severity of coronary artery disease. These patients were classified into two groups according to Synergy between PCI with Taxus and Cardiac Surgery≥23 and Synergy between PCI with Taxus and Cardiac Surgery<23 scores. Biochemical markers such as platelet-to-lymphocyte ratio and neutrophil-to-lymphocyte ratio were studied in blood tests taken before coronary angiography in patients diagnosed with non-ST elevation myocardial infarction according to current guidelines. These two groups were compared in terms of the data obtained.

RESULTS

There were 281 patients in group 1 and 67 patients in group 2. There was no significant difference between the two groups in terms of demographic data such as age and gender. Platelet-to-lymphocyte ratio [group 1=125 (26-134) and group 2=156 (73-293); p=0.001] and neutrophil-to-lymphocyte ratio [group 1=2.71 (1.3-30.2) and group 2=3.2 (2.1-32.1); p=0.002] were higher in the group of patients with a Synergy between PCI with Taxus and Cardiac Surgery score of <23, while lymphocyte-to-monocyte ratio [group 1=3.6 (0.56-11) and group 2=3.4 (0.64-5.75); p=0.017] was lower in group 2.

CONCLUSION

We observed that elevated platelet-to-lymphocyte and neutrophil-to-lymphocyte ratios showed coronary artery severity. Multivessel disease and chronic total occlusion rates were observed to be higher in patients with high platelet-to-lymphocyte and neutrophil-to-lymphocyte ratios.

Platelet-activating factor as an endogenous cofactor of food anaphylaxis

Anaphylaxis is a severe, acute, life-threatening generalized or systemic hypersensitivity reaction. The incidence of anaphylaxis is increasing worldwide, with medications and food contributing to most cases. Physical exercise, acute infections, drugs, alcohol, and menstruation are the external cofactors associated with more severe systemic reaction. The aim of this review is to show that platelet-activating factor contributes to the development of severe anaphylactic reaction, and even to anaphylactic shock.

Marine-Derived Compounds Applied in Cardiovascular Diseases: Submerged Medicinal Industry

Cardiovascular diseases (CVDs) are among the most impactful illnesses globally. Currently, the available therapeutic option has several side effects, including hypotension, bradycardia, arrhythmia, and alteration in different ion concentrations. Recently, bioactive compounds from natural sources, including plants, microorganisms, and marine creatures, have gained a lot of interest. Marine sources serve as reservoirs for new bioactive metabolites with various pharmacological activities. The marine-derived compound such as omega-3 acid ethyl esters, xyloketal B, asperlin, and saringosterol showed promising results in several CVDs. The present review focuses on marine-derived compounds' cardioprotective potential for hypertension, ischemic heart disease, myocardial infarction, and atherosclerosis. In addition to therapeutic alternatives, the current use of marine-derived components, the future trajectory, and restrictions are also reviewed.

Classes of Lipid Mediators and Their Effects on Vascular Inflammation in Atherosclerosis

It is commonly believed that the inactivation of inflammation is mainly due to the decay or cessation of inducers. In reality, in connection with the development of atherosclerosis, spontaneous decay of inducers is not observed. It is now known that lipid mediators originating from polyunsaturated fatty acids (PUFAs), which are important constituents of all cell membranes, can act in the inflamed tissue and bring it to resolution. In fact, PUFAs, such as arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), are precursors to both pro-inflammatory and anti-inflammatory compounds. In this review, we describe the lipid mediators of vascular inflammation and resolution, and their biochemical activity. In addition, we highlight data from the literature that often show a worsening of atherosclerotic disease in subjects deficient in lipid mediators of inflammation resolution, and we also report on the anti-proteasic and anti-thrombotic properties of these same lipid mediators. It should be noted that despite promising data observed in both animal and in vitro studies, contradictory clinical results have been observed for omega-3 PUFAs. Many further studies will be required in order to clarify the observed conflicts, although lifestyle habits such as smoking or other biochemical factors may often influence the normal synthesis of lipid mediators of inflammation resolution.

Interrelationships among platelet-activating factor and lipoprotein-associated phospholipase A2 activity and traditional cardiovascular risk factors

Traditionally cardiovascular disease (CVD) risk has been assessed through blood lipids and inflammatory marker C-reactive protein (hsCRP). Recent clinical interest in novel pro-inflammatory markers platelet-activating factor (PAF) and lipoprotein-associated phospholipase A₂ (Lp-PLA₂ ) recognizes that vascular damage can exist in the absence of traditional risk factors. This cross-sectional study investigated the potential relationship between circulating PAF, Lp-PLA₂ , hsCRP, and traditional risk factors for CVD. One hundred adults (49 ± 13 years, 31% male) with variable CVD risk were recruited. Fasting inflammatory markers PAF, Lp-PLA₂ and hsCRP and total, high-density lipoprotein (HDL), low-density lipoprotein (LDL) cholesterol, and triglycerides were measured. Blood pressure, body mass index, and waist circumference were measured. Medical and physical activity data were self-reported. Linear and multiple regressions were performed. PAF, Lp-PLA₂ , and hsCRP independently correlated with several CVD risk factors. PAF was correlated significantly with risk factors in an unexpected way; there was a medium positive correlation between PAF and HDL cholesterol (r = 0.394, p < 0.001) and medium negative correlations with Total:HDL cholesterol; (r = -0.436, p < 0.001) systolic blood pressure; (r = -0.307, p = 0.001); BMI (r = -0.381, p < 0.001); and waist circumference (r = -0.404, p < 0.001). There were large positive correlations between Lp-PLA₂ and LDL (r = 0.525, p < 0.001) and non-HDL cholesterol (r = 0.508, p < 0.001). There were large positive correlations between hsCRP and Total:HDL cholesterol (r = 0.524, p < 0.001); BMI (r = 0.668, p < 0.001); and waist circumference (r = 0.676, p < 0.001). PAF, Lp-PLA₂ , and hsCRP are implicated in the pathophysiology of inflammation in CVD; however, the relationships between each marker and traditional risk factors were different suggesting they may be involved in different atherogenic pathways.

Quality of Life and Depression Assessment in Patients with Acute Coronary Syndrome: A Cross-Sectional Study

PURPOSE

Acute Coronary Syndrome (ACS) is currently the leading cause of death in industrialized countries. Morbidity after ACS includes physical and mental disorders affecting the patient's whole life situation and Quality of Life (QoL). The main aim of the study was to assess QoL and depression among post-ACS patients.

METHODS

This was a cross-sectional observational study. A total of 112 patients who fulfilled the inclusion criteria were included in this study. A semi-structured questionnaire was administered to the patients to collect data from the patients. In this study, men and women aged 18 - 80 with ACS; patients diagnosed with Non-ST Segment Elevated Myocardial Infarction (NSTEMI) or STEMI or Angina Pectoris were included. Patients with severe mental, and physical illness and dementia were excluded from the study. QoL and depression assessment was done by RAND 36-Item Health Survey and Hamilton Depression Rating scale, respectively.

RESULTS

Among 112 post-ACS patients, 78 patients were males, and 38 patients were females. The mean age of the study population was 64.25 ± 9.029 and with most individuals in the category of 61 - 70 years. The majority of study populations were married (71.5%) and lived with their families (92.9%). In this study group, 42.9 % of the population reported at least high school education (SSLC) and 54.5% were full-time employees. Most of the patients (91.1%) were taking the medication regularly, while 55.4% of patients reported regular compliance with the follow-up. This study identified that, among various factors, older age, female gender, lower income, unemployment, low education status, poor compliance with medication, and depressive symptoms led to poor QoL.

CONCLUSION

This study confirms a negative correlation between depressive symptoms and QoL. This study's results reveal the magnitude of depression that is prevalent in the primary health care clinic that goes undiagnosed and unmanaged. Hence, it is recommended to properly screen depressive symptoms in ACS patients. Therefore, concurrently, better QoL can be achieved by managing both depression and ACS.

The association between dietary patterns and the novel inflammatory markers platelet-activating factor and lipoprotein-associated phospholipase A2: a systematic review

CONTEXT

Atherosclerosis is a disease of chronic inflammation. Recent research has identified 2 novel inflammatory biomarkers: platelet-activating factor (PAF) and lipoprotein-associated phospholipase A2 (Lp-PLA2). Diet has been proposed as a mediator of inflammation, but to date, the focus for these novel biomarkers has been on individual foods and nutrients rather than overall dietary patterns.

OBJECTIVE

To systematically review the literature on the association between dietary patterns and PAF and Lp-PLA2.

DATA SOURCES

The PubMed, Embase, CINAHL, and Cochrane CENTRAL literature databases were searched.

DATA ANALYSIS

Study quality was evaluated using the Quality Criteria Checklist. Sixteen studies (n = 4 observational and n = 12 interventional) were included and assessed for associations between dietary patterns and PAF and Lp-PLA2.

CONCLUSION

Study quality varied from neutral (n = 10) to positive (n = 6). Mediterranean, heart healthy, and vegetarian dietary patterns were associated with improved levels of PAF and Lp-PLA2. Conversely, Western dietary patterns were less favorable. A range of well-established, healthier dietary patterns may lower inflammation and the risk of atherosclerosis. More well-designed studies are needed to confirm these findings and identify other dietary patterns that improve inflammation.

Plasmalogenic Lipid Analogs as Platelet-Activating Factor Antagonists: A Potential Novel Class of Anti-inflammatory Compounds

Plasmalogens and Platelet-Activating Factor (PAF) are both bioactive ether phospholipids. Whereas plasmalogens are recognized for their important antioxidant function and modulatory role in cell membrane structure and dynamics, PAF is a potent pro-inflammatory lipid mediator known to have messenger functions in cell signaling and inflammatory response. The relationship between these two types of lipids has been rarely studied in terms of their metabolic interconversion and reciprocal modulation of the pro-inflammation/anti-inflammation balance. The vinyl-ether bonded plasmalogen lipid can be the lipid sources for the precursor of the biosynthesis of ether-bonded PAF. In this opinion paper, we suggest a potential role of plasmalogenic analogs of PAF as modulators and PAF antagonists (anti-PAF). We discuss that the metabolic interconversion of these two lipid kinds may be explored towards the development of efficient preventive and relief strategies against PAF-mediated pro-inflammation. We propose that plasmalogen analogs, acting as anti-PAF, may be considered as a new class of bioactive anti-inflammatory drugs. Despite of the scarcity of available experimental data, the competition between PAF and its natural plasmalogenic analogs for binding to the PAF receptor (PAF-R) can be proposed as a mechanistic model and potential therapeutic perspective against multiple inflammatory diseases (e.g., cardiovascular and neurodegenerative disorders, diabetes, cancers, and various manifestations in coronavirus infections such as COVID-19).

Antihypertensive effect and underlying mechanism of tripeptide NCW on spontaneously hypertensive rats using metabolomics analysis

Tripeptide NCW identified in our previous study displayed a strong ACE inhibitory activity, but whether it has any antihypertensive effect in vivo remains unknown. Thus, in this study, we aimed to investigate the protective effects of tripeptide NCW in spontaneously hypertensive rats (SHRs) and to further figure out the serum metabolic profiling variations due to its oral administration via UPLC-Q-TOF-MS/MS-based metabolomics analysis to clarify the underlying hypotensive mechanism. After three weeks of oral administration, the tripeptide NCW-treated group (NCW/SHR group, 80 mg per kg BW per d) showed significantly reduced systolic and diastolic blood pressure by 48.08 ± 3.84 mmHg and 48.92 ± 5.77 mmHg, respectively. Additionally, a total of 25 blood pressure-related metabolites were identified as being significantly changed in SHRs given tripeptide NCW after three weeks. These 25 metabolites might be biomarkers that indicated that the tripeptide NCW exhibits antihypertensive activity via regulating bile acid metabolism, lipid metabolism, amino acid metabolism, purinergic signaling, pantothenate and CoA biosynthesis, and the citrate cycle. Collectively, tripeptide NCW has a protective effect on SHRs associated with serum metabolite abnormalities.

The Roles of Platelet-Activating Factor and Magnesium in Pathophysiology of Hypertension, Atherogenesis, Cardiovascular Disease, Stroke and Aging

Hypertension and atherosclerosis are debilitating diseases that affect millions each year. Long-term consequences include but are not limited to stroke, myocardial infarction, and kidney failure. Platelet-activating factor (PAF) is a proinflammatory mediator synthesized from a subclass of phosphatidylcholines that increases platelet activation, leukocyte adhesion, infiltration of macrophages, and intracellular lipid accumulation, thereby contributing to atherosclerosis. Magnesium, a key micronutrient and free radical scavenger, is a water-soluble mineral that regulates peripheral vasodilation and calcium, phosphate, and hydroxyapatite homeostasis. Magnesium’s antihypertensive ability stems from its role as a natural calcium antagonist and promoter of vasodilatory mediators, such as nitric oxide. Platelet-activating factor and magnesium share an inverse relationship, and elevated magnesium levels have been shown to have protective effects against plaque formation as well as antihypertensive and antiarrhythmic effects, all of which allow for healthier aging. The purpose of this literature review is to investigate the role of platelet-activating factor and magnesium in the pathophysiology of hypertension, atherosclerosis, cardiovascular disease, stroke, and aging. Since the pathophysiology of the platelet-activating factor biomolecule is underexplored, further research studies are warranted in order to navigate the putative signaling pathways involved in the cardioprotective effects of dietary magnesium as a natural anti-PAF agent.

PAF Physiology in Target Organ Systems—A Deep Dive to Understand the PAF Mystery in Pathogenesis of Disease

The purpose of this literature review is to gain an overview of the role of platelet-activating factor (PAF) within each of the body systems and how it contributes to normal and pathophysiological states. The review showed that there are multiple functions of PAF that are common to several body systems; however, there is little evidence to explain why PAF has this affect across multiple systems. Interestingly, there seems to be conflicting research as to whether PAF is an overall protective or pathogenic pathway. Within this research, it was found that there are different pathways depending on the specific body system, as well as between body systems. However, one universal function reported in the literature is of PAF as a pro-inflammatory molecule. Overall, this review identified five major functions of PAF: vasoconstriction, increased inflammation, vascular remodeling, increased edema, and endothelial permeability.

Anti-inflammatory, ulcerogenic and platelet activation evaluation of novel 1,4-diaryl-1,2,3-triazole neolignan-celecoxib hybrids

This study reports the synthesis of novel neolignans-celecoxib hybrids and the evaluation of their biological activity. Analogs8-13(L13-L18) exhibited anti-inflammatory activity, inhibited glycoprotein expression (P-selectin) related to platelet activation, and were considered non- ulcerogenic in the animal model, even with the administration of 10 times higher than the dose used in reference therapy. In silico drug-likeness showed that the analogs are compliant with Lipinski's rule of five. A molecular docking study showed that the hybrids8-13(L13-L18) fitted similarly with celecoxib in the COX-2 active site. According to this data, it is possible to infer that extra hydrophobic interactions and the hydrogen interactions with the triazole core may improve the selectivity towards the COX-2 active site. Furthermore, the molecular docking study with P-selectin showed the binding affinity of the analogs in the active site, performing important interactions with amino acid residues such as Tyr 48. Whereas the P-selectin is a promising target to the design of new anti-inflammatory drugs with antithrombotic properties, a distinct butterfly-like structure of 1,4-diaryl-1,2,3-triazole neolignan-celecoxib hybrids synthesized in this work may be a safer alternative to the traditional COX-2 inhibitors.

A Review of Platelet-Activating Factor As a Potential Contributor to Morbidity and Mortality Associated with Severe COVID-19

The precise mechanisms of pathology in severe COVID-19 remains elusive. Current evidence suggests that inflammatory mediators are responsible for the manifestation of clinical symptoms that precedes a fatal response to infection. This review examines the nature of platelet activating factor and emphasizes the similarities between the physiological effects of platelet activating factor and the clinical complications of severe COVID-19.

Inflammatory Biomarkers and Endothelial Alteration in Patients with Heart Failure and Acute Coronary Syndromes

Introduction: Systemic inflammation plays a key role in the pathophysiology of acute coronary syndrome (ACS), having a direct effect in promoting the progression and rupture of vulnerable coronary plaques. The aim of this study was to investigate the association between inflammatory biomarkers and the type of ACS (ST-elevation myocardial infarction – STEMI, non-ST-elevation myocardial infarction – NSTEMI, or unstable angina – UA) in patients with confirmed heart failure.

Material and Methods: This study included a total of 266 patients admitted to the Clinical Department of Cardiology of the County Emergency Clinical Hospital of Târgu Mureș – Cardiac Intensive Care Unit (CICU) for ACS of various types (UA, NSTEMI or STEMI) between January 1, 2017 and December 31, 2020, in whom the diagnosis of heart failure was established based on clinical and paraclinical data. From the total number of patients, 36 were hospitalized for UA and 230 for MI, of which 165 were STEMI and 65 were NSTEMI.

Results: Only hs-CRP and IL-6 were significantly higher in MI compared to UA. Mean hs-CRP was 4.9 ± 4.5 mg/mL in patients with UA vs. 20.4 ± 42.2 mg/mL in patients with MI (p = 0.001), and mean IL-6 was 7.2 ± 13.8 pg/mL in UA vs. 31.6 ± 129.2 pg/mL in MI (p <0.0001). ICAM seems to have had a greater discriminating power between STEMI and other types of ACS in those with heart failure, having a value more than double in those with STEMI (216.1 ± 149.6 ng/mL vs. 448.2 ± 754.4 ng/mL, p <0.0001).

Conclusions: In patients with heart failure, the increase of inflammatory biomarkers such as hs-CRP is associated with the development of an acute myocardial infarction but not with its type. Adhesion molecules, especially ICAM, are elevated in patients with STEMI compared to other types of ACS, indicating a potential role of endothelial alteration in the development of an ACS when it adds to systemic inflammation linked to heart failure.

Plasma metabolites associated with physiological and biochemical indexes indicate the effect of caging stress on mallard ducks (Anas platyrhynchos)

Objective

Cage rearing has critical implications for the laying duck industry because it is convenient for feeding and management. However, caging stress is a type of chronic stress that induces maladaptation. Environmental stress responses have been extensively studied, but no detailed information is available about the comprehensive changes in plasma metabolites at different stages of caging stress in ducks. We designed this experiment to analyze the effects of caging stress on performance parameters and oxidative stress indexes in ducks.

Methods

Liquid chromatography tandem mass spectrometry (LC/MS-MS) was used to determine the changes in metabolites in duck plasma at 5 (CR5), 10 (CR10), and 15 (CR15) days after cage rearing and traditional breeding (TB). The associated pathways of differentially altered metabolites were analyzed using Kyoto encyclopedia of genes and genomes (KEGG) database.

Results

The results of this study indicate that caging stress decreased performance parameters, and the plasma total superoxide dismutase levels were increased in the CR10 group compared with the other groups. In addition, 1,431 metabolites were detected. Compared with the TB group, 134, 381, and 190 differentially produced metabolites were identified in the CR5, CR10, and CR15 groups, respectively. The results of principal component analysis (PCA) show that the selected components sufficiently distinguish the TB group and CR10 group. KEGG analysis results revealed that the differentially altered metabolites in duck plasma from the CR5 and TB groups were mainly associated with ovarian steroidogenesis, biosynthesis of unsaturated fatty acids, and phenylalanine metabolism.

Conclusion

In this study, the production performance, blood indexes, number of metabolites and PCA were compared to determine effect of the caging stress stage on ducks. We inferred from the experimental results that caging-stressed ducks were in the sensitive phase in the first 5 days after caging, caging for approximately 10 days was an important transition phase, and then the duck continually adapted.

Treatment with PCSK9 Inhibitors in Patients with Familial Hypercholesterolemia Lowers Plasma Levels of Platelet-Activating Factor and Its Precursors: A Combined Metabolomic and Lipidomic Approach

INTRODUCTION

Familial hypercholesterolemia (FH) is characterized by extremely high levels of circulating low-density lipoprotein cholesterol (LDL-C) and is caused by mutations of genes involved in LDL-C metabolism, including LDL receptor (LDLR), apolipoprotein B (APOB), or proprotein convertase subtilisin/Kexin type 9 (PCSK9). Accordingly, PCSK9 inhibitors (PCSK9i) are effective in LDL-C reduction. However, no data are available on the pleiotropic effect of PCSK9i. To this end, we performed an untargeted metabolomics approach to gather a global view on changes in metabolic pathways in patients receiving treatment with PCSK9i.

METHODS

Twenty-five FH patients starting treatment with PCSK-9i were evaluated by an untargeted metabolomics approach at baseline (before PCSK9i treatment) and after 12 weeks of treatment.

RESULTS

All the 25 FH subjects enrolled were on maximal tolerated lipid-lowering therapy prior to study entry. After a 12 week treatment with PCSK9i, we observed an expected significant reduction in LDL-cholesterol levels (from 201.0 ± 69.5 mg/dL to 103.0 ± 58.0 mg/dL, p < 0.001). The LDL-C target was achieved in 36% of patients. After peak validation and correction, after 12 weeks of PCSK9i treatment as compared to baseline, we observed increments in creatine (p-value = 0.041), indole (p-value = 0.045), and indoleacrylic acid (p-value= 0.045) concentrations. Conversely, significant decreases in choline (p-value = 0.045) and phosphatidylcholine (p-value < 0.01) together with a reduction in platelet activating factor (p-value = 0.041) were observed.

CONCLUSIONS

Taking advantage of untargeted metabolomics, we first provided evidence of concomitant reductions in inflammation and platelet activation metabolites in FH patients receiving a 12 week treatment with PCSK9i.

Cardiovascular risk and testosterone - from subclinical atherosclerosis to lipoprotein function to heart failure

The cardiovascular (CV) benefit and safety of treating low testosterone conditions is a matter of debate. Although testosterone deficiency has been linked to a rise in major adverse CV events, most of the studies on testosterone replacement therapy were not designed to assess CV risk and thus excluded men with advanced heart failure or recent history of myocardial infarction or stroke. Besides considering observational, interventional and prospective studies, this review article evaluates the impact of testosterone on atherosclerosis process, including lipoprotein functionality, progression of carotid intima media thickness, inflammation, coagulation and thromboembolism, quantification of plaque volume and vascular calcification. Until adequately powered studies evaluating testosterone effects in hypogonadal men at increased CV risk are available (TRAVERSE trial), clinicians should ponder the use of testosterone in men with atherosclerotic cardiovascular disease and discuss benefit and harms with the patients.

Consumption of Enriched Yogurt with PAF Inhibitors from Olive Pomace Affects the Major Enzymes of PAF Metabolism: A Randomized, Double Blind, Three Arm Trial

Platelet-activating factor (PAF), a proinflammatory lipid mediator, plays a crucial role in the formation of the atherosclerotic plaque. Therefore, the inhibition of endothelium inflammation by nutraceuticals, such as PAF inhibitors, is a promising alternative for preventing cardiovascular diseases. The aim of the present study was to evaluate the impact of a new functional yogurt enriched with PAF inhibitors of natural origin from olive oil by-products on PAF metabolism. Ninety-two apparently healthy, but mainly overweight volunteers (35-65 years) were randomly allocated into three groups by block-randomization. The activities of PAF's biosynthetic and catabolic enzymes were measured, specifically two isoforms of acetyl-CoA:lyso-PAF acetyltransferase (LPCATs), cytidine 5'-diphospho-choline:1-alkyl-2-acetyl-sn-glycerol cholinephosphotransferase (PAF-CPT) and two isoforms of platelet activating factor acetylhydrolase in leucocytes (PAF-AH) and plasma (lipoprotein associated phospholipase-A₂, LpPLA₂). The intake of the enriched yogurt resulted in reduced PAF-CPT and LpPLA₂ activities. No difference was observed in the activities of the two isoforms of lyso PAF-AT. In conclusion, intake of yogurt enriched in PAF inhibitors could favorably modulate PAF biosynthetic and catabolic pathways.

Switching the substrate specificity of lysoplasmalogen-specific phospholipase D

Lysoplasmalogen‐specific phospholipase D (LyPls‐PLD) catalyzes reactions in a manner similar to those catalyzed by glycerophosphodiester phosphodiesterase (GDPD) and other well‐known PLDs. Although these enzymes hydrolyze the glycerophosphodiester bond, their substrate specificities are completely different. Previously, we reported that LyPls‐PLD from Thermocrispum sp. RD004668 shows only 53% activity with 1‐hexadecyl‐2‐hydroxy‐sn‐glycero‐3‐phosphocholine (LysoPAF) relative to the 100% activity it shows with choline lysoplasmalogen (LyPlsCho). Lipoprotein‐associated phospholipase A₂ (Lp‐PLA₂) activity can be used to evaluate for cardiovascular disease. Hence, development of a point‐of‐care testing kit requires a LysoPAF‐specific PLD (LysoPAF‐PLD) to measure Lp‐PLA₂ activity. Rational site‐directed mutagenesis and kinetic analysis were applied to generate LysoPAF‐PLD from LyPls‐PLD and to clarify the mechanisms underlying the substrate‐recognition ability of LyPls‐PLD. Our results suggest that LyPls‐PLD variants A47, M71, N173, F211, and W282 are possibly involved in substrate recognition and that F211L may substantially alter substrate preference. Moreover, the specific activity ratio LysoPAF/LyPlsCho corresponding to F211L was up to 25‐fold higher than that corresponding to the wild‐type enzyme. Thus, we succeeded in switching from LyPlsCho‐ to LysoPAF‐PLD. These results suggest that the F211L variant may be utilized to measure Lp‐PLA₂ activity. Kinetic analyses demonstrated that product release was the rate‐limiting step of the reaction, with flexibility of the sn‐1 ether‐linked vinyl/alkyl chain of the substrate being essential for substrate binding and product release. Our findings may lead to a better understanding of the differences between homologous enzymes (such as PLD, sphingomyelinase D, and GDPD of the phosphatidylinositol‐phosphodiesterase superfamily) in relation to substrate recognition.

Enzyme

EC 3.1.4.2 (currently assigned).

Activation of Neutrophil Granulocytes by Platelet-Activating Factor Is Impaired During Experimental Sepsis

Platelet-activating factor (PAF) is an important mediator of the systemic inflammatory response. In the case of sepsis, proper activation and function of neutrophils as the first line of cellular defense are based on a well-balanced physiological response. However, little is known about the role of PAF in cellular changes of neutrophils during sepsis. Therefore, this study investigates the reaction patterns of neutrophils induced by PAF with a focus on membrane potential (MP), intracellular pH, and cellular swelling under physiological and pathophysiological conditions and hypothesizes that the PAF-mediated response of granulocytes is altered during sepsis. The cellular response of granulocytes including MP, intracellular pH, cellular swelling, and other activation markers were analyzed by multiparametric flow cytometry. In addition, the chemotactic activity and the formation of platelet-neutrophil complexes after exposure to PAF were investigated. The changes of the (electro-)physiological response features were translationally verified in a human ex vivo whole blood model of endotoxemia as well as during polymicrobial porcine sepsis. In neutrophils from healthy human donors, PAF elicited a rapid depolarization, an intracellular alkalization, and an increase in cell size in a time- and dose-dependent manner. Mechanistically, the alkalization was dependent on sodium-proton exchanger 1 (NHE1) activity, while the change in cellular shape was sodium flux- but only partially NHE1-dependent. In a pathophysiological altered environment, the PAF-induced response of neutrophils was modulated. Acidifying the extracellular pH in vitro enhanced PAF-mediated depolarization, whereas the increases in cell size and intracellular pH were largely unaffected. Ex vivo exposure of human whole blood to lipopolysaccharide diminished the PAF-induced intracellular alkalization and the change in neutrophil size. During experimental porcine sepsis, depolarization of the MP was significantly impaired. Additionally, there was a trend for increased cellular swelling, whereas intracellular alkalization remained stable. Overall, an impaired (electro-)physiological response of neutrophils to PAF stimulation represents a cellular hallmark of those cells challenged during systemic inflammation. Furthermore, this altered response may be indicative of and causative for the development of neutrophil dysfunction during sepsis.

A lipidomics approach reveals new insights into Crotalus durissus terrificus and Bothrops moojeni snake venoms

Snakebite envenomation causes > 81,000 deaths and incapacities in another 400,000 people worldwide every year. Snake venoms are complex natural secretions comprised of hundreds of different molecules with a wide range of biological functions that after injection cause local and systemic manifestations. Although several studies have investigated snake venoms, the majority have focused on the protein portion (toxins), without significant attention paid to the lipid fraction. Therefore, an untargeted lipidomic approach based on liquid chromatography with high-resolution mass spectrometry (LC-HRMS) was applied to investigate the lipid constituents of venoms of the snake species Crotalus durissus terrificus and Bothrops moojeni. Phosphatidylcholines (PC), Lyso-PCs, phosphatidylethanolamines (PE), Lyso-PE, phosphatidylserine (PS), phosphatidylinositol (PI), ceramides (Cer), and sphingomyelin (SM) species were detected in the analyzed snake venoms. The identified lipids included bioactive compounds such as platelet-activating factor (PAF) precursor, PAF-like molecules, plasmalogens, ceramides, and sphingomyelins with long fatty acid chain lengths, which may be associated with the systemic responses triggered by C. d. terrificus and B. moojeni envenomation. These responses include platelet aggregation, activation of intercellular adhesion molecule 1 (ICAM1), apoptosis, as well as the production of pro-inflammatory lipid mediators, cytokines, and reactive species. The newly proposed lipidomics strategy provided valuable information regarding the lipid profiles of viperid venoms, which could lead to increased understanding of the complex pathology promoted by snakebite envenomation.

Metabolic response of blood vessels to TNFα

TNFα signaling in the vascular endothelium elicits multiple inflammatory responses that drive vascular destabilization and leakage. Bioactive lipids are main drivers of these processes. In vitro mechanistic studies of bioactive lipids have been largely based on two-dimensional endothelial cell cultures that, due to lack of laminar flow and the growth of the cells on non-compliant stiff substrates, often display a pro-inflammatory phenotype. This complicates the assessment of inflammatory processes. Three-dimensional microvessels-on-a-chip models provide a unique opportunity to generate endothelial microvessels in a more physiological environment. Using an optimized targeted liquid chromatography–tandem mass spectrometry measurements of a panel of pro- and anti-inflammatory bioactive lipids, we measure the profile changes upon administration of TNFα. We demonstrate that bioactive lipid profiles can be readily detected from three-dimensional microvessels-on-a-chip and display a more dynamic, less inflammatory response to TNFα, that resembles more the human situation, compared to classical two-dimensional endothelial cell cultures.

In a range of conditions called autoimmune diseases, the immune system attacks the body rather than foreign elements. This can cause inflammation that is harmful for many organs. In particular, immune cells can produce excessive amounts of a chemical messenger called tumor necrosis factor alpha (TNFα for short), which can lead to the release of fatty molecules that damage blood vessels.

This process is normally studied in blood vessels cells that are grown on a dish, without any blood movement. However, in this rigid 2D environment, the cells become ‘stressed’ and show higher levels of inflammation than in the body. This makes it difficult to assess the exact role that TNFα plays in disease.

A new technology is addressing this issue by enabling scientist to culture blood vessels cells in dishes coated with gelatin. This allows the cells to organize themselves in 3D, creating tiny blood vessels in which fluids can flow. However, it was unclear whether these ‘microvessels-on-a-chip’ were better models to study the role of TNFα compared to cells grown on a plate.

Here, Junaid et al. compared the levels of inflammation in blood vessels cells grown in the two environments, showing that cells are less inflamed when they are cultured in 3D. In addition, when the artificial 3D-blood vessels were exposed to TNFα, they responded more like real blood vessels than the 2D models. Finally, experiments showed that it was possible to monitor the release of fatty molecules in this environment. Together, this work suggests that microvessels-on-a-chip are better models to study how TNFα harms blood vessels.

Next, systems and protocols could be develop to allow automated mass drug testing in microvessels-on-a-chip. This would help scientists to quickly screen thousands of drugs and find candidates that can protect blood vessels from TNFα.

Relationship Between Platelet to Lymphocyte Ratio and Stable Coronary Artery Disease: Meta-Analysis of Observational Studies

Recent studies have reported a relationship between the platelet to lymphocyte ratio (PLR) and acute coronary syndromes. The aim of the present study was to investigate the association between PLR and stable coronary artery disease (CAD). A systematic search was conducted based on electronic databases (Cochrane, PubMed, Elsevier, Medline, and Embase). A total of 14 studies (n = 4,871) were included in the meta-analysis. Compared with the non-CAD group, PLR was significantly higher in CAD group (P = .002). After further classification according to the Gensini score, the cases with atherosclerosis demonstrated a higher PLR than those without atherosclerosis (P < .001). Platelet to lymphocyte ratio was higher in the severe atherosclerosis group compared with the mild atherosclerosis group (P < .001). Compared with the poor coronary collateral circulation (CCC) group, PLR was significantly lower in the good CCC group (P < .001). The PLR was significantly higher in patients with coronary slow flow (CSF) than those with normal coronary flow (P = .01). On the basis of current evidence, an elevated PLR was associated with stable CAD, and it might be useful for predicting CAD severe stenosis, collateral circulation, and CSF. Future studies are needed to clarify the relationship between PLR and stable CAD.

Depression Related Pathophysiologies Relevant in Heart Disease: Insights into the Mechanism Based on Pharmacological Treatments

Depressive symptoms are highly prevalent in patients with cardiac diseases. Co-morbid Depression in cardiac patients causes a significant reduction in health-related quality of life for the patients and inflicts an economic burden on the society. Two types of mechanisms that may explain the link between depression and cardiac diseases are the psychosocial and physiopathological mechanisms. Physiopathological mechanisms are direct biological mechanisms, which include hyperactivity of non-adrenergic and Hypothalamic Pituitary Adrenal Axis (HPA), abnormal platelet activation, endothelial dysfunction, and inflammatory process. Psychosocial factors include behavioral or lifestyle factors like smoking alcoholism and physical inactivity. Pharmacologic and therapeutic interventions are effective at reducing symptoms of depression in patients with cardiac disorders. Among pharmacological treatment, SSRIs seems to be effective for the reduction of depressive symptoms among patients with cardiac disorders because of their good efficacy and minimal cardiovascular side effects. Mechanisms of action of SSRI’s in depressive patients with cardiac disorders are associated with their ability to reduce inflammation, platelet, and endothelial dysfunction. This review focuses on the potential pathophysiological and psychosocial links between cardiac diseases and depression, the treatment options, and the importance of routine screening of depressive symptoms in cardiac settings.

Platelet activation and prothrombotic mediators at the nexus of inflammation and atherosclerosis: Potential role of antiplatelet agents

Platelets are central to inflammation-related manifestations of cardiovascular diseases (CVD) such as atherosclerosis. Platelet-activating factor (PAF), thrombin, thromboxane A₂ (TxA₂), and adenosine diphosphate (ADP) are some of the key agonists of platelet activation that are at the intersection between a plethora of inflammatory pathways that modulate pro-inflammatory and coagulation processes. The aim of this article is to review the role of platelets and the relationship between their structure, function, and the interactions of their constituents in systemic inflammation and atherosclerosis. Antiplatelet therapies are discussed with a view to primary prevention of CVD by the clinical reduction of platelet reactivity and inflammation. Current antiplatelet therapies are effective in reducing cardiovascular risk but increase bleeding risk. Novel therapeutic antiplatelet approaches beyond current pharmacological modalities that do not increase the risk of bleeding require further investigation. There is potential for specifically designed nutraceuticals that may become safer alternatives to pharmacological antiplatelet agents for the primary prevention of CVD but there is serious concern over their efficacy and regulation, which requires considerably more research.

Mechanism of tanshinones and phenolic acids from Danshen in the treatment of coronary heart disease based on co-expression network

Background

The tanshinones and phenolic acids in Salvia miltiorrhiza (also named Danshen) have been confirmed for the treatment of coronary heart disease (CHD), but the action mechanisms remain elusive.

Methods

In the current study, the co-expression protein interaction network (Ce-PIN) was used to illustrate the differences between the tanshinones and phenolic acids of Danshen in the treatment of CHD. By integrating the gene expression profile data and protein-protein interactions (PPIs) data, the Ce-PINs of tanshinones and phenolic acids were constructed. Then, the Ce-PINs were analyzed by gene ontology enrichment analyzed based on the optimal algorithm.

Results

It turned out that Danshen is able to treat CHD by regulating the blood circulation, immune response and lipid metabolism. However, phenolic acids may regulate the blood circulation by Extracellular calcium-sensing receptor (CaSR), Endothelin-1 receptor (EDNRA), Endothelin-1 receptor (EDNRB), Kininogen-1 (KNG1), tanshinones may regulate the blood circulation by Guanylate cyclase soluble subunit alpha-1 (GUCY1A3) and Guanylate cyclase soluble subunit beta-1 (GUCY1B3). In addition, both the phenolic acids and tanshinones may regulate the immune response or inflammation by T-cell surface glycoprotein CD4 (CD4), Receptor-type tyrosine-protein phosphatase C (PTPRC).

Conclusion

Through the same targets of the same biological process and different targets of the same biological process, the tanshinones and phenolic acids synergistically treat coronary heart disease.

Inflammation and cardiovascular disease: are marine phospholipids the answer?

This review presents the latest research on the cardioprotective effects of n-3 fatty acids (FA) and n-3 FA bound to polar lipids (PL). Overall, n-3 PL may have enhanced bioavailability and potentially bioactivityversusfree FA and ester forms of n-3 FA.

Forty Years Since the Structural Elucidation of Platelet-Activating Factor (PAF): Historical, Current, and Future Research Perspectives

In the late 1960s, Barbaro and Zvaifler described a substance that caused antigen induced histamine release from rabbit platelets producing antibodies in passive cutaneous anaphylaxis. Henson described a ‘soluble factor’ released from leukocytes that induced vasoactive amine release in platelets. Later observations by Siraganuan and Osler observed the existence of a diluted substance that had the capacity to cause platelet activation. In 1972, the term platelet-activating factor (PAF) was coined by Benveniste, Henson, and Cochrane. The structure of PAF was later elucidated by Demopoulos, Pinckard, and Hanahan in 1979. These studies introduced the research world to PAF, which is now recognised as a potent phospholipid mediator. Since its introduction to the literature, research on PAF has grown due to interest in its vital cell signalling functions and more sinisterly its role as a pro-inflammatory molecule in several chronic diseases including cardiovascular disease and cancer. As it is forty years since the structural elucidation of PAF, the aim of this review is to provide a historical account of the discovery of PAF and to provide a general overview of current and future perspectives on PAF research in physiology and pathophysiology.

Re-Evaluating Biologic Pharmacotherapies that Target the Host Response during Sepsis

Multiple organ dysfunction syndrome (MODS) caused by the systemic inflammatory response during sepsis is responsible for millions of deaths worldwide each year, and despite broad consensus concerning its pathophysiology, no specific or effective therapies exist. Recent efforts to treat and/or prevent MODS have included a variety of biologics, recombinant proteins targeting various components of the host response to the infection (e.g., inflammation, coagulation, etc.) Improvements in molecular biology and pharmaceutical engineering have enabled a wide range of utility for biologics to target various aspects of the systemic inflammatory response. The majority of clinical trials to date have failed to show clinical benefit, but some have demonstrated promising results in certain patient populations. In this review we summarize the underlying rationale and outcome of major clinical trials where biologics have been tested as a pharmacotherapy for MODS in sepsis. A brief description of the study design and overall outcome for each of the major trials are presented. Emphasis is placed on discussing targets and/or trials where promising results were observed. Post hoc analyses of trials where therapy demonstrated harm or additional risk to certain patient subgroups are highlighted, and details are provided about specific trials where more stringent inclusion/exclusion criteria are warranted.

Hyperbaric Oxygen Treatment is Associated with Lipid Inflammatory Response Assessed Uding Serum Platelet Activating Factor

Hyperbaric oxygen (HBO) treatment is generally a relatively safe therapy for various conditions. However, there are some adverse side effects. For example HBO tratment has been reported to increase the production of free oxygen radicals(FRs). Furthermore, to our knowledge, no previous clinical research has been carried out to study the involvement of platelet-activating factor(PAF)as the lipid oxidative stressor in patients undergoing HBO treatment. A total of 45 patients included in this study were first given clinical assessment and laboratory measurements before starting HBO treatment and were named group baseline. After the HBO treatment, the same clinical and laboratory measurements from the same patients were repeated and this was named group sesion >20.As expected, long-term HBO treatment had no effect on oxLDL (oxidized low-density lipoprotein), a lipid oxidative stress(OS) marker. However, the mean PAF values in the second group showed a statistically significant increase compared to their pretreatment values, (P <0. 002).As this is a preliminary study, there is a need for more detailed investigations that demonstrate the association of HBO treatment with the lipid inflammatory response. Therefore, there is need for further clinical study for OS markers such as oxLDL in HBO treatment. Clinical prospective studies are required to confirm our laboratory findings.

Platelet Inflammatory Response to Stress

Blood platelets play a central hemostatic role, (i) as they repair vascular epithelial damage, and (ii) they play immune defense roles, as they have the capacity to produce and secrete various cytokines, chemokines, and related products. Platelets sense and respond to local dangers (infectious or not). Platelets, therefore, mediate inflammation, express and use receptors to bind infectious pathogen moieties and endogenous ligands, among other components. Platelets contribute to effective pathogen clearance. Damage-associated molecular patterns (DAMPs) are danger signals released during inflammatory stress, such as burns, trauma and infection. Each pathogen is recognized by its specific molecular signature or pathogen-associated molecular pattern (PAMP). Recent data demonstrate that platelets have the capacity to sense external danger signals (DAMPs or PAMPs) differentially through a distinct type of pathogen recognition receptor (such as Toll-like receptors). Platelets regulate the innate immune response to pathogens and/or endogenous molecules, presenting several types of “danger” signals using a complete signalosome. Platelets, therefore, use complex tools to mediate a wide range of functions from danger sensing to tissue repair. Moreover, we noted that the secretory capacity of stored platelets over time and the development of stress lesions by platelets upon collection, processing, and storage are considered stress signals. The key message of this review is the “inflammatory response to stress” function of platelets in an infectious or non-infectious context.

Association of platelet count with all-cause mortality and risk of cardiovascular and respiratory morbidity in stable COPD

Background

Platelet count is a prognostic indicator in the general population and elderly. Thrombocytosis during acute exacerbation of COPD (AECOPD) has been associated with mortality; however, the relationship between platelet count and mortality in stable COPD is unknown.

Methods

We performed post hoc secondary analysis on a subsample of 1797 patients in the Study to Understand Mortality and Morbidity in COPD (SUMMIT) who had blood samples drawn at baseline. Participants were current or former smokers, 40–80 years old with moderate COPD and history or increased risk of cardiovascular (CV) disease. The primary outcome was on and post-treatment all-cause mortality. Secondary outcomes included first-on-treatment moderate/severe AECOPD and on-treatment CV composite event (CV death, myocardial infarction, stroke, unstable angina and transient ischemic attack). Multivariable Cox proportional hazards models were used to investigate study endpoint associations with platelet count quintile grouping, continuous platelet count utilizing two-term fractional polynomials, and categories of low, normal and high platelet count (< 150, ≥150 to < 300, ≥300 × 10⁹/L).

Results

Patients were followed for 2.3 ± 0.9 years for vital status and 1.6 ± 1.1 years for morbidity endpoints during which 105 (5.8%) died, 651 (36.2%) experienced AECOPD (159 with severe AECOPD) and 86 (4.8%) experienced a CV event. A U-shaped association between platelet count and all-cause mortality was observed. Compared to the third quintile group (Q3) of platelet count, risk of death was increased in the lowest quintile group (Q1; hazard ratio [HR]: 1.73; 95% confidence interval [CI]: 0.93–3.23) and highest quintile group (Q5; HR: 1.66; 95%CI: 0.89–3.10), though point estimates were imprecise. Using clinical cutoffs, compared with normal platelet counts (≥150 to < 300 × 10⁹/L), risk of all-cause mortality was nominally increased among patients with thrombocytopenia (HR: 1.46; 95%CI: 0.81–2.64) and high platelet count (HR: 1.66; 95%CI: 0.96–2.86). Compared with Q3, CV events were nominally increased for Q5 (HR: 1.71; 95%CI: 0.83–3.49) and Q1 (HR: 1.41; 95%CI: 0.70, 2.85). There was no association between platelet count and AECOPD.

Conclusions

In stable COPD platelet count demonstrated a U-shaped association with increased risk of 3-year all-cause mortality, though a platelet count level above or below which risk of mortality was increased could not be definitively identified.

Trial registration

ClinicalTrials.gov NCT01313676.

Chlorogenic Acid Attenuates Dextran Sodium Sulfate-Induced Ulcerative Colitis in Mice through MAPK/ERK/JNK Pathway

Objective

Observe the protective effect of chlorogenic acid on dextran sulfate-induced ulcerative colitis in mice and explore the regulation of MAPK/ERK/JNK signaling pathway.

Methods

Seventy C57BL/6 mice (half males and half females) were randomly divided into 7 groups, 10 in each group: control group (CON group), UC model group (UC group), and sulfasalazine-positive control group (SASP group), chlorogenic acid low dose group (CGA-L group), chlorogenic acid medium dose group (CGA-M group), chlorogenic acid high dose group (CGA-H group), and ERK inhibitor + chlorogenic acid group (E+CGA group). The effects of chlorogenic acid on UC were evaluated by colon mucosa damage index (CMDI), HE staining, immunohistochemistry, ELISA, and Western blot. The relationship between chlorogenic acid and MAPK/ERK/JNK signaling pathway was explored by adding ERK inhibitor.

Results

The UC models were established successfully by drinking DSS water. Chlorogenic acid reduces DSS-induced colonic mucosal damage, inhibits DSS-induced inflammation, oxidative stress, and apoptosis in colon, and reduces ERK1/2, p -ERK, p38, p-p38, JNK, and p-JNK protein expression. ERK inhibitor U0126 reversed the protective effect of chlorogenic acid on colon tissue.

Conclusion

Chlorogenic acid can alleviate DSS-induced ulcerative colitis in mice, which can significantly reduce tissue inflammation and apoptosis, and its mechanism is related to the MAPK/ERK/JNK signaling pathway.

Changes in the Canine Plasma Lipidome after Short- and Long-Term Excess Glucocorticoid Exposure

Glucocorticoids (GCs) are critical regulators of metabolic control in mammals and their aberrant function has been linked to several pathologies. GCs are widely used in human and veterinary clinical practice as potent anti-inflammatory and immune suppressive agents. Dyslipidaemia is a frequently observed consequence of GC treatment, typified by increased lipolysis, lipid mobilization, liponeogenesis, and adipogenesis. Dogs with excess GC show hyperlipidaemia, hypertension, and a higher risk of developing type 2 diabetes mellitus, but the risk of developing atherosclerotic lesions is low as compared to humans. This study aimed to examine alterations in the canine plasma lipidome in a model of experimentally induced short-term and long-term GC excess. Both treatments led to significant plasma lipidome alterations, which were more pronounced after long-term excess steroid exposure. In particular, monohexosylceramides, phosphatidylinositols, ether phosphatidylcholines, acyl phosphatidylcholines, triacylglycerols and sphingosine 1-phosphates showed significant changes. The present study highlights the hitherto unknown effects of GCs on lipid metabolism, which will be important in the further elucidation of the role and function of GCs as drugs and in metabolic and cardiovascular diseases.

Update of inflammatory proliferative retinopathy: Ischemia, hypoxia and angiogenesis

Diabetic retinopathy (DR) and retinopathy of prematurity (ROP) present two examples of proliferative retinopathy, characterized by the same stages of progression; ischemia of the retinal vessels, leads to hypoxia and to correct the problem there is the setting up of uncontrolled angiogenesis, which subsequently causes blindness or even detachment of the retina. The difference is the following; that DR initiated by the metabolic complications that are due to hyperglycemia, and ROP is induced by overexposure of the neonatal retina to oxygen. In this review, we will demonstrate the physiopathological mechanism of the two forms of proliferative retinopathy DR and ROP, in particular the role of the CD40/CD40L axis and IL-1 on vascular complications and onset of inflammation of the retina, the implications of their effects on the onset of pathogenic angiogenesis, thus understanding the link between platelets and retinal ischemia. In addition, what are the therapeutic targets that could slow its progression?

Hydroxysafflor Yellow A Suppresses Platelet Activating Factor-Induced Activation of Human Small Airway Epithelial Cells

Hydroxysafflor yellow A (HSYA) is a chemical component isolated from the Chinese medicine Carthamus tinctorius L. HSYA has numerous pharmacological effects, including protecting against and mitigating some respiratory diseases such as acute lung injury and chronic obstructive pulmonary disease; however, its effect on asthma remains unclear. We previously found that HSYA attenuated ovalbumin-induced allergic asthma in guinea pigs. Platelet activating factor (PAF) is a phospholipid mediator of inflammation and an important factor in the pathological process of asthma. In this study, we investigated the anti-inflammatory effects of HSYA and its underlying mechanisms in PAF-induced human small airway epithelial cells (HSAECs). PAF-activated cells were pretreated with HSYA and/or the PAF receptor inhibitor, ginkgolide B, and we observed changes in the expression of interleukin (IL)-1β, IL-6, and tumor necrosis factor alpha, monolayer permeability of HSAECs, and inflammatory signaling pathways. HSYA attenuated the PAF-induced increase in expression of inflammatory factors and destruction of cell-barrier function, and inhibited the expression of protein kinase C, mitogen-activated protein kinases, activator protein-1, and nuclear factor-κB activation induced by PAF. These findings suggest that HSYA may represent a potential new drug for the treatment of asthma.

Inflammation, not Cholesterol, Is a Cause of Chronic Disease

Since the Seven Countries Study, dietary cholesterol and the levels of serum cholesterol in relation to the development of chronic diseases have been somewhat demonised. However, the principles of the Mediterranean diet and relevant data linked to the examples of people living in the five blue zones demonstrate that the key to longevity and the prevention of chronic disease development is not the reduction of dietary or serum cholesterol but the control of systemic inflammation. In this review, we present all the relevant data that supports the view that it is inflammation induced by several factors, such as platelet-activating factor (PAF), that leads to the onset of cardiovascular diseases (CVD) rather than serum cholesterol. The key to reducing the incidence of CVD is to control the activities of PAF and other inflammatory mediators via diet, exercise, and healthy lifestyle choices. The relevant studies and data supporting these views are discussed in this review.

Phospholipid signaling in innate immune cells

Phospholipids comprise a large body of lipids that define cells and organelles by forming membrane structures. Importantly, their complex metabolism represents a highly controlled cellular signaling network that is essential for mounting an effective innate immune response. Phospholipids in innate cells are subject to dynamic regulation by enzymes, whose activities are highly responsive to activation status. Along with their metabolic products, they regulate multiple aspects of innate immune cell biology, including shape change, aggregation, blood clotting, and degranulation. Phospholipid hydrolysis provides substrates for cell-cell communication, enables regulation of hemostasis, immunity, thrombosis, and vascular inflammation, and is centrally important in cardiovascular disease and associated comorbidities. Phospholipids themselves are also recognized by innate-like T cells, which are considered essential for recognition of infection or cancer, as well as self-antigens. This Review describes the major phospholipid metabolic pathways present in innate immune cells and summarizes the formation and metabolism of phospholipids as well as their emerging roles in cell biology and disease.

Novel enzymatic method for assaying Lp-PLA2 in serum

BACKGROUND

Measurement of lipoprotein-associated phospholipase A₂ (Lp-PLA₂) can be used as an adjunct to traditional cardiovascular risk factors for identifying individuals at higher risk of cardiovascular events. This can be performed by quantification of the protein concentration using an ELISA platform or by measuring Lp-PLA₂ activity using platelet-activating factor (PAF) analog as substrate. Here, an enzymatic Lp-PLA₂ activity assay method using 1-O-Hexadecyl-2-acetyl-rac-glycero-3-phosphocholine (rac C₁₆ PAF) was developed.

METHODS

The newly revealed substrate specificity of lysoplasmalogen-specific phospholipase D (lysophospholipase D (LysoPLD)) was exploited. Lp-PLA₂ hydrolyzes 1-O-Hexadecyl-2-acetyl-sn-glycero-3-phosphocholine (C₁₆ PAF) to 1-O-Hexadecyl-2-hydroxy-sn-glycero-3-phosphocholine (LysoPAF). LysoPLD acted on LysoPAF, and the hydrolytically released choline was detected by choline oxidase.

RESULTS

Regression analysis of Lp-PLA₂ activity measured by the enzymatic Lp-PLA₂ activity assay vs. two chemical Lp-PLA₂ activity assays, i.e. LpPLA₂ FS and PLAC® test, and ELISA, gave the following correlation coefficients: 0.990, 0.893 and 0.785, respectively (n = 30).

CONCLUSION

Advantages of this enzymatic Lp-PLA₂ activity assay compared with chemical Lp-PLA₂ methods include the following; (i) only requires two reagents enabling a simple two-point linear calibration method with one calibrator (ii) no need for inhibitors of esterase-like activity in serum.

Dairy Fats and Cardiovascular Disease: Do We Really Need to be Concerned?

Cardiovascular diseases (CVD) remain a major cause of death and morbidity globally and diet plays a crucial role in the disease prevention and pathology. The negative perception of dairy fats stems from the effort to reduce dietary saturated fatty acid (SFA) intake due to their association with increased cholesterol levels upon consumption and the increased risk of CVD development. Institutions that set dietary guidelines have approached dairy products with negative bias and used poor scientific data in the past. As a result, the consumption of dairy products was considered detrimental to our cardiovascular health. In western societies, dietary trends indicate that generally there is a reduction of full-fat dairy product consumption and increased low-fat dairy consumption. However, recent research and meta-analyses have demonstrated the benefits of full-fat dairy consumption, based on higher bioavailability of high-value nutrients and anti-inflammatory properties. In this review, the relationship between dairy consumption, cardiometabolic risk factors and the incidence of cardiovascular diseases are discussed. Functional dairy foods and the health implications of dairy alternatives are also considered. In general, evidence suggests that milk has a neutral effect on cardiovascular outcomes but fermented dairy products, such as yoghurt, kefir and cheese may have a positive or neutral effect. Particular focus is placed on the effects of the lipid content on cardiovascular health.