Platelet activating factor in heart failure: potential role in disease progression and novel target for therapy

Phytochemicals as Chemo-Preventive and Therapeutic Agents Against Bladder Cancer: A Comprehensive Review

Bladder cancer has a high incidence worldwide and is characterized by a high recurrence rate, metastatic potential, and a significant socioeconomic burden. Conventional treatment modalities usually exhibit serious adverse complications, which also negatively affect patients' quality of life. In the context of exploring new treatment approaches with fewer side effects, the utilization of natural compounds as alternative and/or complementary therapeutic options seems appealing. In the present study, the potential use and effects of various bioactive phytochemicals, including curcumin, resveratrol, epigallocatechin, genistein, and several others, in bladder cancer treatment are thoroughly reviewed. A special focus is given to their potential to beneficially modulate important molecular signaling pathways and mechanisms affecting cell survival, proliferation, migration, and apoptosis, which play a crucial role in the pathogenesis of bladder cancer, such as the PI3K/AKT/mTOR, Ras/Raf/MEK/MAPK, Wnt/β-Catenin, Notch, Hedgehog, Hippo, JAK2/STAT3, and PAF/PAF-receptor pathways. Nevertheless, most studies have been conducted in cell cultures and animal models. Due to differences in genetics and metabolism, more clinical trials are needed to ensure the bio-efficacy of these phytochemicals in humans.

Dietary Restriction of Advanced Glycation End-Products (AGEs) in Patients with Diabetes: A Systematic Review of Randomized Controlled Trials

Advanced Glycation End Products (AGEs) are formed through non-enzymatic reactions between reducing sugars and proteins, nucleic acids or lipids (for example through hyperoxidation). In diabetes, elevated glucose levels provide more substrate for AGEs formation. AGEs can also be ingested through the diet from foods cooked at high temperatures, or containing much sugar. The present work aimed to review all published randomized controlled trials (RCT) on low-dietary AGE (L-dAGEs) interventions in patients with diabetes. Pubmed, Scopus and Cochrane databases were searched (until 29 February 2024) with appropriate keywords (inclusion criteria: RCT, patients with diabetes, age > 18 years, outcomes related to inflammation, glucose, and lipids; exclusion criteria: non-RCTs, case-series, case reports and Letter to the Editor, or animal studies). The present review was registered to the Open Science Framework (OSF). From 7091 studies, seven were ultimately included. Bias was assessed with the updated Cochrane Risk of Bias tool. A reduction in circulating AGEs was documented in 3/3 studies. No particular differences were documented in glycemic parameters after a L-dAGEs diet. Reductions in glucose levels were observed in one out of six studies (1/6), while HbA1c and HOMA did not change in any study (0/6 and 0/3, correspondingly). Lipid profile also changed in one out of four studies (1/4). More consistent results were observed for oxidative stress (beneficial effects in 3/3 studies) and inflammatory markers (beneficial effects in 4/4 studies). Other athero-protective effects, such as adiponectin increases, were reported. Limitations included the small sample size and the fact that dietary and physical activity habits were not considered in most studies. In conclusion, a L-dAGEs pattern may minimize AGEs accumulation and have beneficial effects on oxidative stress and inflammation indices, while its effects on glycemic and lipemic parameters are inconsistent and modest in patients with diabetes.

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.

Associations of phase angle with platelet-activating factor metabolism and related dietary factors in healthy volunteers

Introduction

Phase angle (PA) is derived from bioelectrical impedance analysis (BIA). It reflects cell membrane function and decreases in disease. It is affected by inflammation, oxidative stress, and diet. Platelet-activating factor (PAF) is a potent inflammatory lipid mediator. Its levels, along with the activity of its metabolic enzymes, including CDP-choline:1-alkyl-2-acetyl-sn-glycerol-cholinephosphotransferase, acetyl-CoA:lyso-PAF-acetyltransferases, and PAF-AH/Lp-PLA2 are also related to dietary factors, such as the dietary antioxidant capacity (DAC). The aim of the study was to estimate whether the PAF metabolic circuit and related dietary factors are associated with PA in healthy volunteers.

Methods

In healthy subjects, PAF, its metabolic enzyme activity, and erythrocyte fatty acids were measured, while desaturases were estimated. Food-frequency questionnaires and recalls were used, and food groups, macronutrient intake, MedDietScore, and DAC were assessed. Lifestyle and biochemical variables were collected. DXA and BIA measurements were performed.

Results

Lp-PLA2 activity was positively associated with PA (rho = 0.651, p < 0.001, total population; rho = 0.780, p < 0.001, women), while PAF levels were negatively associated with PA only in men (partial rho = -0.627, p = 0.012) and inversely related to DAC. Estimated desaturase 6 was inversely associated with PA (rho = -0.404, p = 0.01, total sample). Moreover, the DAC correlated positively with PA (rho = 0.513, p = 0.03, women). All correlations were adjusted for age, body mass index, and sex (if applicable).

Conclusion

PA is associated with PAF levels and Lp-PLA2 activity in a gender-dependent fashion, indicating the involvement of PAF in cell membrane impairment. The relationship of PA with DAC suggests a protective effect of antioxidants on cellular health, considering that antioxidants may inhibit PAF generation.

The Interplay among Glucocorticoid Therapy, Platelet-Activating Factor and Endocannabinoid Release Influences the Inflammatory Response to COVID-19

COVID-19 is associated with a dysregulated immune response. Currently, several medicines are licensed for the treatment of this disease. Due to their significant role in inhibiting pro-inflammatory cytokines and lipid mediators, glucocorticoids (GCs) have attracted a great deal of attention. Similarly, the endocannabinoid (eCB) system regulates various physiological processes including the immunological response. Additionally, during inflammatory and thrombotic processes, phospholipids from cell membranes are cleaved to produce platelet-activating factor (PAF), another lipid mediator. Nonetheless, the effect of GCs on this lipid pathway during COVID-19 therapy is still unknown. This is a cross-sectional study involving COVID-19 patients (n = 200) and healthy controls (n = 35). Target tandem mass spectrometry of plasma lipid mediators demonstrated that COVID-19 severity affected eCBs and PAF synthesis. This increased synthesis of eCB was adversely linked with systemic inflammatory markers IL-6 and sTREM-1 levels and neutrophil counts. The use of GCs altered these lipid pathways by reducing PAF and increasing 2-AG production. Corroborating this, transcriptome analysis of GC-treated patients blood leukocytes showed differential modulation of monoacylglycerol lipase and phospholipase A2 gene expression. Altogether, these findings offer a breakthrough in our understanding of COVID-19 pathophysiology, indicating that GCs may promote additional protective pharmacological effects by influencing the eCB and PAF pathways involved in the disease course.

The platelet to lymphocyte ratio in heart failure: a comprehensive review

Introduction. At the crossroads of heart failure (HF) and systemic inflammation, platelets and lymphocytes are both influenced as well as actively participating in the bidirectional relationship. The platelet to lymphocyte ratio (PLR) could therefore be a marker of severity. This review aimed to assess the role of PLR in HF. Methods. We searched the PubMed (MEDLINE) database using the keywords "platelet", "thrombocyte", "lymphocyte", "heart failure", "cardiomyopathy", "implantable cardioverter defibrillator", "cardiac resynchronization therapy" and "heart transplant". Results. We identified 320 records. 21 studies were included in this review, with a total of 17,060 patients. PLR was associated with age, HF severity, and comorbidity burden. Most studies reported the predictive power for all-cause mortality. Higher PLR was associated with in-hospital and short-term mortality in univariable analysis, however, it was not consistently an independent predictor for this outcome. PLR > 272.9 associated an adjusted HR of 3.22 (95%CI 1.56 - 5.68, p<0.001) for 30-day fatality. During long-term follow-up from 6 months to 5 years, PLR was an independent predictor of mortality in most studies, with cut-off values ranging from > 150 to > 194.97 and adjusted HR from 1.47 (95%CI 1.06 - 2.03, p=0.019) to 5.65 (95%CI 2.47-12.96, p<0.001). PLR > 173.09 had an adjusted OR 2.89 (95%CI 1.17-7.09, p=0.021) for predicting response to cardiac resynchronization therapy. PLR was not associated with outcomes after cardiac transplant or implantable cardioverter-defibrillator. Conclusion: Increased PLR could be an auxiliary biomarker of severity and survival prognosis in HF patients.

Critical role of PAFR/YAP1 positive feedback loop in cardiac fibrosis

Aberrant activation of cardiac fibroblasts is the main cause and character of cardiac fibrosis, and inhibition of cardiac fibrosis becomes a promising treatment for cardiac diseases. Platelet-activating factor (PAF) and Hippo pathway is recently recognized as key signaling mechanisms in cardiovascular diseases. In this study we explored the potential roles of PAF and Hippo signaling pathway in cardiac fibrosis. Myocardial infarction (MI) was induced in mice by left anterior descending artery ligation. After 28 days, the mice were sacrificed, and the hearts were collected for analyses. We showed that PAF receptor (PAFR) and yes-associated protein 1 (YAP1, a key effector in the Hippo pathway) were significantly increased in the heart of MI mice. Increased expression of PAFR and YAP1 was also observed in angiotensin II (Ang II)-treated mouse cardiac fibroblasts. In mouse cardiac fibroblasts, forced expression of YAP1 increased cell viability, resulted in collagen deposition and promoted fibroblast-myofibroblast transition. We showed that PAF induced fibrogenesis through activation of YAP1 and promoted its nuclear translocation via interacting with PAFR, while YAP1 promoted the expression of PAFR by binding to and activating transcription factor TEAD1. More importantly, silencing PAFR or YAP1 by shRNA, or using transgenic mice to induce the conditional deletion of YAP1 in cardiac fibroblasts, impeded cardiac fibrosis and improved cardiac function in MI mice. Taken together, this study elucidates the role and mechanisms of PAFR/YAP1 positive feedback loop in cardiac fibrosis, suggesting a potential role of this pathway as novel therapeutic targets in cardiac fibrosis.

Topical application of gemcitabine generates microvesicle particles in human and murine skin

Chemotherapy has remained the mainstay for the treatment of multiple types of cancers. In particular, topical use of chemotherapy has been used for skin cancers. Though effective, topical chemotherapy has been limited due to adverse effects such as local and even systemic toxicities. Our recent studies demonstrated that exposure to pro-oxidative stressors, including therapeutic agents induces the generation of extracellular vesicles known as microvesicle particles (MVP) which are dependent on activation of the Platelet-activating factor-receptor (PAFR), a G-protein coupled receptor present on various cell types, and acid sphingomyelinase (aSMase), an enzyme required for MVP biogenesis. Based upon this premise, we tested the hypothesis that topical application of gemcitabine will induce MVP generation in human and murine skin. Our ex vivo studies using human skin explants demonstrate that gemcitabine treatment results in MVP generation in a dose-dependent manner in a process blocked by PAFR antagonist and aSMase inhibitor. Importantly, gemcitabine-induced MVPs carry PAFR agonists. To confirm the mechanisms, we employed PAFR-expressing and deficient (Ptafr-/- ) mouse models as well as mice deficient in aSMase enzyme (Spmd1-/- ). Similar to the findings using pharmacologic tools, genetic-based approaches demonstrate that gemcitabine-induced MVP release in WT mice was blunted in Ptafr-/- and Spmd1-/- mice. These findings demonstrate a novel mechanism by which local chemotherapy can generate bioactive components as a bystander effect in a process that is dependent upon the PAFR-aSMase pathway.

Micronutrients, Phytochemicals and Mediterranean Diet: A Potential Protective Role against COVID-19 through Modulation of PAF Actions and Metabolism

The new coronavirus disease 2019 (COVID-19) pandemic is an emerging situation with high rates of morbidity and mortality, in the pathophysiology of which inflammation and thrombosis are implicated. The disease is directly connected to the nutritional status of patients and a well-balanced diet is recommended by official sources. Recently, the role of platelet activating factor (PAF) was suggested in the pathogenesis of COVID-19. In the present review several micronutrients (vitamin A, vitamin C, vitamin E, vitamin D, selenium, omega-3 fatty acids, and minerals), phytochemicals and Mediterranean diet compounds with potential anti-COVID activity are presented. We further underline that the well-known anti-inflammatory and anti-thrombotic actions of the investigated nutrients and/or holistic dietary schemes, such as the Mediterranean diet, are also mediated through PAF. In conclusion, there is no single food to prevent coronavirus Although the relationship between PAF and COVID-19 is not robust, a healthy diet containing PAF inhibitors may target both inflammation and thrombosis and prevent the deleterious effects of COVID-19. The next step is the experimental confirmation or not of the PAF-COVID-19 hypothesis.

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.

In vitro Anti-atherogenic Properties of N-Heterocyclic Carbene Aurate(I) Compounds

The anti-atherogenic (anti-inflammatory) properties of various aurate(I) salts, of the general formula [NHC⋅H][AuCl₂ ] (NHC=N-heterocyclic carbene) were investigated. The aurates were easily synthesized and obtained in analytically pure form. In addition, the biological activity of these compounds against atheromatosis via in vitro inhibition of platelet-activating factor (PAF)-induced platelet aggregation was probed. All complexes were found to possess anti-aggregatory properties in vitro with [IPr*⋅H][AuCl₂ ] (6) being the most potent inhibitor of PAF at micromolar concentration. Based on our findings, we conclude that these simply assembled aurates are a very promising class of PAF inhibitors and anti-inflammatory drugs.

Mediterranean diet and platelet-activating factor; a systematic review

Platelet-activating factor (PAF) is a glycerylether lipid and one of the most potent endogenous mediators of inflammation. Through its binding to a well-characterized receptor it initiates a plethora of cellular pro-inflammatory actions participating by this way to the pathology of most chronic diseases, including cardiovascular and renal diseases, CNS decline and cancer. Among the variety of prudent dietary patterns, Mediterranean Diet (MD) is the dietary pattern with the strongest evidence for its ability to prevent the same chronic diseases. In addition, micronutrients and extracts from several components and characteristic food of the MD can favorably modulate PAF's actions and metabolism either directly or indirectly. However, the role of this traditional diet on PAF metabolism and actions has rarely been studied before. This systematic review summarizes, presents and discusses the outcomes of epidemiologic and intervention studies in humans, investigating the relationships between PAF status and MD. Seventeen full-text articles trying to interlink the components of MD and PAF are found and presented. The results are inconsistent due to the variability of the measured indices and methodology followed. However, preliminary results indicate that the characteristic "healthy" components of the MD, especially, cereals, legumes, vegetables, fish and wine can favorably modulate the pro-inflammatory actions of PAF and regulate its metabolism. Larger, well-controlled studies are necessary to elucidate whether the attenuation of PAF actions can mediate the preventive properties of MD against chronic diseases.

A metabolomics study of Qiliqiangxin in a rat model of heart failure: a reverse pharmacology approach

The Chinese medicine Qiliqiangxin (QL) has been shown to have a protective role in heart failure. Here, we explore the underlying working mechanism of the key therapeutic component in QL using a rat model of heart failure. Heart failure after myocardial infarction was induced surgically and confirmed using echocardiography; a separate group of rats underwent sham surgery. The rats with heart failure were randomly assigned to receive QL, the angiotensin-converting enzyme inhibitor benazepril, or placebo groups. Blood samples were collected from the rats at four time points for up to 8 weeks and used for biochemical analysis and mass spectrometry‒based metabolomics profiling. In total, we measured nine well-known biochemical parameters of heart failure and 147 metabolites. In the rats with heart failure, QL significantly improved these biochemical parameters and metabolomics profiles, significantly increasing the cardioprotective parameter angiopoietin-like 4 and significantly lowering inflammation-related oxylipins and lysophosphatidic acids compared to benazepril. Mechanistically, QL may improve outcome in heart failure by controlling inflammatory process and cardiac hypertrophy. Clinical studies should be designed in order to investigate these putative mechanisms in patients.

LncRNA PFL contributes to cardiac fibrosis by acting as a competing endogenous RNA of let-7d

Rationale: Cardiac fibrosis is associated with various cardiovascular diseases and can eventually lead to heart failure. Dysregulation of long non-coding RNAs (lncRNAs) has recently been recognized as one of the key mechanisms involved in cardiac diseases. However, the potential roles and underlying mechanisms of lncRNAs in cardiac fibrosis have not been explicitly delineated. Methods and Results: Using a combination of in vitro and in vivo studies, we identified a lncRNA NONMMUT022555, which is designated as a pro-fibrotic lncRNA (PFL), and revealed that PFL is up-regulated in the hearts of mice in response to myocardial infarction (MI) as well as in the fibrotic cardiac fibroblasts (CFs). We found that knockdown of PFL by adenoviruses carrying shRNA attenuated cardiac interstitial fibrosis and improved ejection fraction (EF) and fractional shortening (FS) in MI mice. Further study showed that forced expression of PFL promoted proliferation, fibroblast-myofibroblast transition and fibrogenesis in mice CFs by regulating let-7d, whereas silencing PFL mitigated TGF-β1-induced myofibroblast generation and fibrogenesis. More importantly, PFL acted as a competitive endogenous RNA (ceRNA) of let-7d, as forced expression of PFL reduced the expression and activity of let-7d. Moreover, let-7d levels were decreased in the MI mice and in fibrotic CFs. Inhibition of let-7d resulted in fibrogenesis in CFs, whereas forced expression of let-7d abated fibrogenesis through targeting platelet-activating factor receptor (Ptafr). Furthermore, overexpression of let-7d by adenoviruses carrying let-7d precursor impeded cardiac fibrosis and improved cardiac function in MI mice. Conclusion: Taken together, our study elucidated the role and mechanism of PFL in cardiac fibrosis, indicating the potential role of PFL inhibition as a novel therapy for cardiac fibrosis.

Clinical Evidence Supports a Protective Role for CXCL5 in Coronary Artery Disease

Our goal was to measure the association of CXCL5 and molecular phenotypes associated with coronary atherosclerosis severity in patients at least 65 years old. CXCL5 is classically defined as a proinflammatory chemokine, but its role in chronic inflammatory diseases, such as coronary atherosclerosis, is not well defined. We enrolled individuals who were at least 65 years old and undergoing diagnostic cardiac catheterization. Coronary artery disease (CAD) severity was quantified in each subject via coronary angiography by calculating a CAD score. Circulating CXCL5 levels were measured from plasma, and both DNA genotyping and mRNA expression levels in peripheral blood mononuclear cells were quantified via microarray gene chips. We observed a negative association of CXCL5 levels with CAD at an odds ratio (OR) of 0.46 (95% CI, 0.27-0.75). Controlling for covariates, including sex, statin use, hypertension, hyperlipidemia, obesity, self-reported race, smoking, and diabetes, the OR was not significantly affected [OR, 0.54 (95% CI, 0.31-0.96)], consistent with a protective role for CXCL5 in coronary atherosclerosis. We also identified 18 genomic regions with expression quantitative trait loci of genes correlated with both CAD severity and circulating CXCL5 levels. Our clinical findings are consistent with the emerging link between chemokines and atherosclerosis and suggest new therapeutic targets for CAD.

Understanding the connection between platelet-activating factor, a UV-induced lipid mediator of inflammation, immune suppression and skin cancer

Lipid mediators of inflammation play important roles in several diseases including skin cancer, the most prevalent type of cancer found in the industrialized world. Ultraviolet (UV) radiation is a complete carcinogen and is the primary cause of skin cancer. UV radiation is also a potent immunosuppressive agent, and UV-induced immunosuppression is a well-known risk factor for skin cancer induction. An essential mediator in this process is the glyercophosphocholine 1-alkyl-2-acetyl-sn-glycero-3-phosphocholine commonly referred to as platelet-activating factor (PAF). PAF is produced by keratinocytes in response to diverse stimuli and exerts its biological effects by binding to a single specific G-protein-coupled receptor (PAF-R) expressed on a variety of cells. This review will attempt to describe how this lipid mediator is involved in transmitting the immunosuppressive signal from the skin to the immune system, starting from its production by keratinocytes, to its role in activating mast cell migration in vivo, and to the mechanisms involved that ultimately lead to immune suppression. Recent findings related to its role in regulating DNA repair and activating epigenetic mechanisms, further pinpoint the importance of this bioactive lipid, which may serve as a critical molecular mediator that links the environment (UVB radiation) to the immune system and the epigenome.

Roles of specific lipid species in the cell and their molecular mechanism

Thousands of different molecular species of lipids are present within a single cell, being involved in modulating the basic processes of life. The vast number of different lipid species can be organized into a number of different lipid classes, which may be defined as a group of lipids with a common chemical structure, such as the headgroup, apart from the nature of the hydrocarbon chains. Each lipid class has unique biological roles. In some cases, a relatively small change in the headgroup chemical structure can result in a drastic change in function. Such phenomena are well documented, and largely understood in terms of specific interactions with proteins. In contrast, there are observations that the entire structural specificity of a lipid molecule, including the hydrocarbon chains, is required for biological activity through specific interactions with membrane proteins. Understanding of these phenomena represents a fundamental change in our thinking of the functions of lipids in biology. There are an increasing number of diverse examples of roles for specific lipids in cellular processes including: Signal transduction; trafficking; morphological changes; cell division. We are gaining knowledge and understanding of the underlying molecular mechanisms. They are of growing importance in both basic and applied sciences.

Fatty acids and cardiac disease: fuel carrying a message

From the viewpoint of the prevention of cardiovascular disease (CVD) burden, there has been a continuous interest in the detrimental effects of the Western-type high-fat diet for more than half a century. More recently, this general view has been subject to change as epidemiological studies showed that replacing fat by carbohydrate may even be worse and that various polyunsaturated fatty acids (FA) have beneficial rather than detrimental effects on CVD outcome. At the same time, advances in lipid biology have provided insight into the mechanisms by which the different lipid components of the Western diet affect the cardiovascular system. In fact, this still is a rapidly growing field of research and in recent years novel FA derivatives and FA receptors have been discovered. This includes fish-oil derived FA-derivatives with anti-inflammatory properties, the so-called resolvins, and various G-protein-coupled receptors that recognize FA as ligands. In the present review, we will extensively discuss the role of FA and their metabolites on cardiac disease, with special emphasis on the role of the different saturated and polyunsaturated FA and their respective metabolites in cellular signal transduction and the possible implications for the development of cardiac hypertrophy and cardiac failure.

Clinical application of elevated platelet-activating factor acetylhydrolase in patients with hepatitis B

Background

The aim of this study was to investigate the variation of platelet-activating factor acetylhydrolase (PAF-AH) in patients with various stages of hepatitis B infection and evaluate the association between PAF-AH activity and chronic severe hepatitis B (CSHB) and mortality in patients with hepatitis B.

Methods

Serum PAF-AH activity was measured in 216 patients with hepatitis B and in 152 healthy controls using an automatic biochemical analysis system. Spearman correlation was used to investigate the correlation between PAF-AH activity and other biochemical indicators. The receiver operating characteristic (ROC) curve and multivariable logistic regression analysis were used to evaluate the ability of PAF-AH activity to predict CSHB and mortality in patients with hepatitis B.

Results

The PAF-AH activities in patients with CSHB (1320 ± 481 U/L) were significantly higher than those in healthy controls and in other hepatitis B groups (all P < 0.01). In patients with hepatitis B, PAF-AH activity correlated with total bilirubin (r = 0.633), total bile acid (r = 0.559), aspartate aminotransferase (r = 0.332), apolipoprotein B (r = 0.348), high-density lipoprotein cholesterol (r = −0.493), and apolipoprotein AI (r = −0.530). The areas under the ROC curves for the ability of PAF-AH activity to predict CSHB and mortality in patients with hepatitis B were 0.881 (95% confidence interval (CI): 0.824–0.937, P < 0.001) and 0.757 (95% CI: 0.677–0.837, P < 0.001), respectively. Multivariate logistic regression analysis showed PAF-AH activity to be an independent factor predicting CSHB with an odds ratio of 1.003 (95% CI: 1.002–1.005, P < 0.001).

Conclusion

Elevated PAF-AH in patients with hepatitis B was significantly associated with liver damage. Thus, serum PAF-AH could be used as a novel indicator for predicting CSHB and mortality in patients with hepatitis B. Further, PAF-AH activity was an independent factor predicting CSHB.

Baseline elevated Lp-PLA2 is associated with increased risk for re-stenosis after stent placement

Background

Lipoprotein associated phospholipase A2 (Lp-PLA2) is a novel biomarker for cardiovascular risk prediction. Whether increased Lp-PLA2 level is associated with re-stenosis after stent-placement is unclear.

Methods

Totally 326 participants eligible for stent-placement were enrolled and divided into two groups according to baseline Lp-PLA2 levels (named normal and elevated groups). Baseline characteristics and clinical outcomes were compared between normal and elevated groups. The relationships between Lp-PLA2 and other risk factors with re-stenosis were evaluated.

Results

Only the between-group difference of Lp-PLA2 was significant (123.2 ± 33.6 ng/mL vs 336.8 ± 85.4 ng/mL, P < 0.001) while other demographic and clinical characteristics between these two groups were comparable. Approximately 55.1% and 58.5% of participants in normal and elevated groups presented with acute coronary syndrome, and the percentage of tri-vessels stenoses was significantly higher in elevated group (40.8% vs 32.1%, P = 0.016). Nearly 96.0% and 94.0% of participants in normal and elevated Lp-PLA2 groups were placed with drug-eluting stents, and the others were with bare-metal stents. After 1 year’s follow-up, the incidence of clinical end-points was comparable (13.3% vs 15.4%, P = 0.172). Nevertheless, the incidence of re-stenosis was marginally higher in elevated Lp-PLA2 group (8.5% versus 4.6%, P = 0.047). With multivariate analysis, after adjustment for other risk factors, Lp-PLA2 remained an independent predictor for re-stenosis with a hazard ratio of 1.140. No synergistic effect between Lp-PLA2 and other risk factors for re-stenosis was found.

Conclusion

Increased Lp-PLA2 level is associated with an increased risk of re-stenosis. Lp-PLA2 assessment may be useful in predicting subjects who are at increased risk for re-stenosis.