Comparative diagnostic accuracy of serum levels of neutrophil activating peptide-2 and pentraxin-3 versus troponin-I in acute coronary syndrome

Pentraxin-3: A new parameter in predicting the severity of diabetic foot infection?

This study was undertaken to evaluate the diagnostic and prognostic values of pentraxin-3 (PTX-3) in patients with infected diabetic foot ulcers (IDFU) as well as to assess the association between PTX-3 levels and IDFU severity. This study included 60 IDFU patients (Group 1), 45 diabetic patients without DFU (Group 2), and 45 healthy controls. Patients with IDFU were divided into mild, moderate, and severe subgroups based on classification of clinical severity. Patients who underwent amputation were also documented. Blood samples were collected to determine PTX-3 levels. PTX-3 levels in healthy controls, Group 1, and Group 2 were 5.83 (3.41-20) ng/mL, 1.47 (0.61-15.13) ng/mL, and 3.26 (0.67-20) ng/mL, respectively. A negative correlation between plasma PTX-3 and glucose levels was found. There were significant differences in terms of procalcitonin (PCT) and PTX-3 levels in the subgroup analysis of Group 1. The PTX-3 level in patients who did or did not undergo amputation was 4.1 (0.8-13.7) and 1 (0.6-15.1) ng/mL, respectively. Results suggest that PTX-3 is a particularly effective marker in patients with IDFU, both in terms of predicting disease severity and assisting in the decision to perform amputation.

Plasma NAP-2 levels are associated with critical limb ischemia in peripheral arterial disease patients

IMPACT STATEMENT

Critical limb ischemia (CLI) is a serious arterial obstruction, resulting in serious reduction of blood flow to the extremities. CLI is a symptomatic disorder and is frequently not diagnosed in time. This results in a high mortality and elevated risk of limb amputation. Serum or plasma biomarkers play important roles in disease prevention, diagnosis, and prognosis. Elevated plasma neutrophil-activating peptide-2 (NAP-2) was found independently associated with CLI, but not with T2DM. Plasma NAP-2 levels might be an early CLI diagnostic biomarker and might provide a novel target for CLI treatment.

Vascular pentraxin 3 controls arterial thrombosis by targeting collagen and fibrinogen induced platelets aggregation

Aim

The long pentraxin PTX3 plays a non-redundant role during acute myocardial infarction, atherosclerosis and in the orchestration of tissue repair and remodeling during vascular injury, clotting and fibrin deposition. The aim of this work is to investigate the molecular mechanisms underlying the protective role of PTX3 during arterial thrombosis.

Methods and results

PTX3 KO mice transplanted with bone marrow from WT or PTX3 KO mice presented a significant reduction in carotid artery blood flow following FeCl₃ induced arterial thrombosis (− 80.36 ± 11.5% and − 95.53 ± 4.46%), while in WT mice transplanted with bone marrow from either WT or PTX3 KO mice, the reduction was less dramatic (− 45.55 ± 1.37% and − 53.39 ± 9.8%), thus pointing to a protective effect independent of a hematopoietic cell's derived PTX3. By using P-selectin/PTX3 double KO mice, we further excluded a role for P-selectin, a target of PTX3 released by neutrophils, in vascular protection played by PTX3. In agreement with a minor role for hematopoietic cell-derived PTX3, platelet activation (assessed by flow cytometric expression of markers of platelet activation) was similar in PTX3 KO and WT mice as were haemostatic properties. Histological analysis indicated that PTX3 localizes within the thrombus and the vessel wall, and specific experiments with the N-terminal and the C-terminal PTX3 domain showed the ability of PTX3 to selectively dampen either fibrinogen or collagen induced platelet adhesion and aggregation.

Conclusion

PTX3 interacts with fibrinogen and collagen and, by dampening their pro-thrombotic effects, plays a protective role during arterial thrombosis.

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PTX3 deficiency in non-hematopoietic cells results in increased arterial thrombosis.

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Defects in the PTX3-P-selectin axis are not responsible for increased arterial thrombosis.

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PTX3 might limit the pro-thrombotic potential of fibrinogen and collagen on platelets adhesion and aggregation.

Assessment of the prophylactic role of aspirin and/or clopidogrel on experimentally induced acute myocardial infarction in hypercholesterolemic rats

Introduction

Hyperlipidemia is a risk factor for cardiovascular diseases such as acute infarction. Inflammation and platelet activation are critical phenomena in acute myocardial infarction (AMI).

Aim

The aim of the study was to assess potential protective effects of aspirin and/or clopidogrel on AMI in hypercholesterolemic rats.

Methods

Forty adult male Wistar rats were divided into five groups (eight rats in each). Group I included normal healthy rats. The other 32 rats were subjected to induction of hypercholesterolemia by high-fat diet for 3 weeks, followed by induction of AMI by subcutaneous injections of isoproterenol (85 mg/kg/day, for 2 days). Rats were divided into the following groups: group II, rats with induced hypercholesterolemia and AMI; group III, hypercholesterolemic rats that received aspirin 30 mg/kg/day orally for 7 days before induction of AMI; group IV, hypercholesterolemic rats that received clopidogrel 10 mg/kg/day orally for 7 days before induction of AMI; and group V, hypercholesterolemic rats treated with both aspirin and clopidogrel in the same doses for 7 days before induction of AMI. Serum levels of pentraxin 3 (PTX3), transforming growth factor-β1 (TGF-β1), creatine kinase (CK), lactate dehydrogenase (LDH), total cholesterol and triglycerides were estimated in all rats.

Results

Isoproterenol-induced AMI in hypercholesterolemic rats was associated with an increase in serum levels of PTX3, TGF-β1, CK and LDH. Aspirin and/or clopidogrel pretreatment for 1 week led to a reduction of their levels as compared with non-treated rats. However, the reduction caused by combination of aspirin and clopidogrel was more than that caused by each drug separately.

Conclusion

Combination of aspirin and clopidogrel could be a therapeutic option for hypercholesterolemic patients to attenuate the complex vascular inflammatory process which is a key step in the setting of AMI.

Consolidated and emerging inflammatory markers in coronary artery disease

Coronary artery disease is an event of atherosclerosis characterized by a chronic vascular inflammation. Risk factors like obesity, diabetes mellitus, hypertension, smoking, hypercholesterolemia and positive family history sometimes are not sufficiently adequate to the enhancement of cardiovascular risk assessment. In the past years numerous biomarkers, like C reactive protein, cytokines and adhesion molecules, have been observed to be related to adverse cardiovascular prognosis. Recently, several studies found an association among inflammatory biomarkers and cardiovascular diseases suggesting their utility to identify the risk of an acute ischemic event and the detection of vulnerable plaques. The emerging inflammatory markers are well divided for diagnosis and prognosis and plaque instability of coronary artery disease. Some of them, the lectin-like oxidized low density lipoprotein receptor-1 can be important both in diagnosis and in the evaluation of plaque instability, other are inserted in the above reported classification. The emerging inflammatory markers in acute-phase include amyloid A, fibrinogen and pentraxin 3 while myeloperoxidase, myeloid-related protein 8/14 and pregnancy-associated plasma protein-A are recognize markers of plaque instability. Lastly, some studies demonstrated that circulating miRNAs are involved in coronary artery disease, acute myocardial infarction and heart failure.

Pentraxin 3 as a prognostic biomarker in patients with systemic inflammation or infection

Purpose. The long pentraxin 3 (PTX3) is a key component of the humoral arm of the innate immune system. PTX3 is produced locally in response to proinflammatory stimuli. We reviewed the usefulness of systemic levels of PTX3 in critically ill patients with systemic inflammatory response syndrome (SIRS), sepsis, and bacteremia, focusing on its diagnostic and prognostic value. Methods. A PubMed search on PTX3 was conducted. The list of papers was narrowed to original studies of critically ill patients. Eleven papers on original studies of critically ill patients that report on PTX3 in SIRS, sepsis, or bacteremia were identified. Results. Systematic levels of PTX3 have little diagnostic value in critically ill patients with SIRS, sepsis, or bacteremia. Systemic levels of PTX3, however, have superior prognostic power over other commonly used biological markers in these patients. Systemic levels of PTX3 correlate positively with markers of organ dysfunction and severity-of-disease classification system scores. Finally, systemic levels of PTX3 remain elevated in the acute phase and decreased on recovery. Notably, the age of the patients and underlying disease affect systemic levels of PTX3. Conclusions. The diagnostic value of PTX3 is low in patients with sepsis. Systemic levels of PTX3 have prognostic value and may add to prognostication of patients with SIRS or sepsis, complementing severity-of-disease classification systems and other biological markers.

Long pentraxin 3: experimental and clinical relevance in cardiovascular diseases

Pentraxin 3 (PTX3) is an essential component of the humoral arm of innate immunity and belongs, together with the C-reactive protein (CRP) and other acute phase proteins, to the pentraxins' superfamily: soluble, multifunctional, pattern recognition proteins. Pentraxins share a common C-terminal pentraxin domain, which in the case of PTX3 is coupled to an unrelated long N-terminal domain. PTX3 in humans, like CRP, correlates with surrogate markers of atherosclerosis and is independently associated with the risk of developing vascular events. Studies addressing the potential physiopathological role of CRP in the cardiovascular system were so far inconclusive and have been limited by the fact that the sequence and regulation have not been conserved during evolution between mouse and man. On the contrary, the conservation of sequence, gene organization, and regulation of PTX3 supports the translation of animal model findings in humans. While PTX3 deficiency is associated with increased inflammation, cardiac damage, and atherosclerosis, the overexpression limits carotid restenosis after angioplasty. These observations point to a cardiovascular protective effect of PTX3 potentially associated with the ability of tuning inflammation and favor the hypothesis that the increased levels of PTX3 in subjects with cardiovascular diseases may reflect a protective physiological mechanism, which correlates with the immunoinflammatory response observed in several cardiovascular disorders.

Host-protective effect of circulating pentraxin 3 (PTX3) and complex formation with neutrophil extracellular traps

Pentraxin 3 (PTX3) is a soluble pattern recognition receptor which is classified as a long-pentraxin in the pentraxin family. It is known to play an important role in innate immunity, inflammatory regulation, and female fertility. PTX3 is synthesized by specific cells, primarily in response to inflammatory signals. Among these various cells, neutrophils have a unique PTX3 production system. Neutrophils store PTX3 in neutrophil-specific granules and then the stored PTX3 is released and localizes in neutrophil extracellular traps (NETs). Although certain NET components have been identified, such as histones and anti-microbial proteins, the detailed mechanisms by which NETs localize, as well as capture and kill microbes, have not been fully elucidated. PTX3 is a candidate diagnostic marker of infection and vascular damage. In severe infectious diseases such as sepsis, the circulating PTX3 concentration increases greatly (up to 100 ng/mL, i.e., up to 100-fold of the normal level). Even though it is clearly implied that PTX3 plays a protective role in sepsis and certain other disorders, the detailed mechanisms by which it does so remain unclear. A proteomic study of PTX3 ligands in septic patients revealed that PTX3 forms a complex with certain NET component proteins. This suggests a role for PTX3 in which it facilitates the efficiency of anti-microbial protein pathogen clearance by interacting with both pathogens and anti-microbial proteins. We discuss the possible relationships between PTX3 and NET component proteins in the host protection afforded by the innate immune response. The PTX3 complex has the potential to be a highly useful diagnostic marker of sepsis and other inflammatory diseases.