Sara Bozzini

Galectin-3 plasma levels and coronary artery disease: a new possible biomarker of acute coronary syndrome.

Inflammation plays a key role in atherosclerosis. Galectin-3 is a macrophage- and endothelium-derived mediator actively involved in the regulation of many aspects of inflammatory cell behaviour. The aim of this study is to quantify plasma Galectin-3 in patients with coronary artery disease (CAD) and different clinical manifestation at the moment of observation in order to verify whether Galectin-3 could be a useful biomarker of atherosclerotic state. We enrolled 125 patients affected by CAD, angiographically documented (70 stable, 55 unstable). They underwent accurate examinations and anamnestic data was collected. The most important traditional risk factors, such as age, hypertension, and body mass index, were reported. Plasma Galectin-3 was quantified using an ELISA kit. Unstable patients (n = 55) had a higher plasma Galectin-3 levels in respect to the stable subjects (27.75 ng/mL (19.27–39.09) vs 6.48 ng/ml (4.88–8.83), p<0.001. A trend in correlation between plasma Galectin-3 levels and number of vessels compromised seems to be present: CAD patients with three-vessel disease had higher levels of Galectin-3 than patients with one-or two-vessel disease (17.39 ng/ml (10.75–29.82) vs 9.18 ng/ml (5.56–23.22), p= 0.058. The significantly higher plasma Galectin-3 levels in patients with unstable angina in respect to the stable angina confirm the involvement of Galectin-3 in promoting macrophage activation and monocyte attraction. Despite the distribution of CAD in patients with acute and chronic coronary disease being similar, we may hypothesize that Galectin-3 could be a useful biomarker of atherosclerotic plaque and in particular of its destabilization.

Soluble RAGE Plasma Levels in Patients with Coronary Artery Disease and Peripheral Artery Disease

The objective of the present study was define in a relatively large patient population with coronary artery disease (CAD) whether the concomitant presence of peripheral artery disease (PAD), which is known to convey additional cardiovascular risk, was associated with different circulating levels of sRAGE with respect to CAD alone and control subjects. Clinical and laboratory parameters including the ankle brachial index (ABI) and sRAGE (enzyme-linked immunosorbent assay kit) were investigated in 544 patients with angiographically documented CAD and 328 control subjects. 213/554 CAD patients (39%) showed an ABI <0.9 associated with typical symptoms (group CAD + PAD), whereas 331 patients were free from PAD. The concentration of plasma sRAGE was significantly lower (P < 0.0001) in CAD population, with and without PAD, than in control subjects. Among CAD patients, those with PAD showed lower levels of sRAGE. The distribution of the three groups (CAD, CAD + PAD, and controls) according to sRAGE tertiles showed that lower levels were more frequent in patients with CAD and CAD + PAD, whereas higher levels were more frequently found in controls. CAD patients presenting with PAD have lower sRAGE levels than CAD patients without peripheral atherosclerosis showing that stable atherosclerotic lesions in different vascular districts are inversely related to soluble decoy receptor sRAGE.

Age of Onset of Myocardial Infarction: Is Promoter Polymorphism of the RAGE Gene Implicated?

Receptor for advanced glycation endproducts (RAGE) is a cell-surface molecule member of the immunoglobulin superfamily and engages differing ligands relevant to distinct processes. A growing body of evidence has suggested that RAGE may promote vascular inflammation through several mechanisms. The objective of this study was to identify the possible relationship between the -374 T/A polymorphism of the RAGE gene, myocardial infarction (MI), and its age of onset. A total of 691 MI patients and 234 matched controls were investigated. In this study, the frequency of the A allele and AA genotype of the -374 T/A promoter polymorphism is significantly lower in patients with MI respect to the control group (p < 0.01). Our results showed a significant role of the AA genotype on age of onset of MI. In particular, the mean age of the first MI was higher in patients with the AA genotype as compared to those that were AT or TT genotype carriers (p = 0.002). The relationship between -374 T/A RAGE polymorphism and age for the appearance of MI was independently related to common risk factors of disease (p < 0.01). Kaplan-Meier curves confirmed that subjects with the AA genotype have a later development of MI (p = 0.0022). This study is the first to investigate the role of RAGE polymorphisms on the susceptibility to develop the acute coronary events in the Italian population and identified this polymorphism as an age-related factor for MI development. The homozygous AA genotype may exert a protective role against the early development of MI.

Autoantibodies, Polymorphisms in the Serotonin Pathway, and Human Leukocyte Antigen Class II Alleles in Chronic Fatigue Syndrome Are They Associated with Age at Onset and Specific Symptoms?

This study aimed to determine the influence of autoantibodies, polymorphisms in the serotonin pathway, and human leukocyte antigen (HLA) class II genes on age at chronic fatigue syndrome (CFS) onset and symptoms. Eighty‐one CFS patients were enrolled, and clinical data were recorded. Autoantibodies to different components of the central nervous system were tested. Polymorphisms in the promoter of the serotonin transporter gene (l/s) and a single nucleotide polymorphism in the serotonin receptor‐2A gene (A/G) as well as HLA class II alleles were determined. Multivariate logistic‐regression analyses were carried out. The mean age at CFS onset ± SD was 33.5 ± 12.5 years. An age at CFS onset (ACFSO) during the third decade of life was associated with the serotonin receptor AA genotype and the HLA‐DRB1*03 allele. An ACFSO during the fourth decade of life was associated with the HLA‐DRB1*07 allele, whereas an ACFSO ≥ 43 years was associated with having at least one copy of the serotonin G allele. Concerning CFS symptoms, the serotonin AG genotype was protective against depressive symptoms. Although having at least one copy of the serotonin A allele and being female were associated with risk for arthralgia, the presence of antineuronal cell antibodies was protective against this. Episodes of unexplained fever were associated with the HLA‐DRB1*11 allele. None of the genetic or serological features was associated with myalgia. None of the antibodies determined correlated with any ACFSO or other symptoms. Our results reveal that in CFS, like other autoimmune diseases, different genetic features are related to age at CFS onset and symptoms.

Plasma Levels of Soluble Receptor for Advanced Glycation End Products and Coronary Atherosclerosis: Possible Correlation with Clinical Presentation

Receptor for Advanced Glycation End-products (RAGE) is a multi-ligand receptor ubiquitous present on epithelial, neuronal, vascular and inflammatory cells, usually expressed at low levels in homeostasis and to increased degrees at sites of stress or injury. The aim of the present study was to evaluate sRAGE plasma levels in patients with Acute Coronary Syndrome (ACS) and to assess its diagnostic efficacy in identification of patients with acute events. Plasma levels of sRAGE were determined in 860 patients with Coronary Artery Disease (CAD): 530 patients presented stable angina and 330 were observed during acute ischemic event (147 with unstable angina and 183 with myocardial infarction). sRAGE plasma levels were significantly lower in patients with ACS than in patients with stable angina: [median 584 pg/mL (IQR: 266–851 pg/mL) in MI patients, median 769 pg/mL (IQR: 394–987 pg/mL) in patients with unstable angina, median 834 pg/mL (IQR 630–1005 pg/mL) in patients with stable angina; P < 0.001]. sRAGE levels did not differ among ACS patients stratified by the extent of coronary artery disease. In conclusion, this study confirm the role of sRAGE in activation and progression of inflammatory process and suggests the possibility that sRAGE can be considered an indicator of destabilization of vulnerable plaque.

Molecular study of receptor for advanced glycation endproduct gene promoter and identification of specific HLA haplotypes possibly involved in chronic fatigue syndrome.

The receptor for advanced glycation end product (RAGE) is thought to play an important role in inflammation. Chronic Fatigue Syndrome (CFS) is a long-lasting fatigue that compromises at least 50% of a subjects daily activities without other known cause. Immune dysfunction has been implicated and an association with a peculiar genetic cytokine profile, predisposing to an immunomodulatory response of inflammatory nature, was found. The aim of this study is to analyse RAGE polymorphisms and HLA-DRB1 alleles in seventy-five Italian CFS patients and 141 controls matched for age, sex and ethnicity. These two groups underwent genomic study for RAGE –374T/A and –429C/T promoter polymorphisms; moreover, 46 patients and 186 controls were typed for HLA-DRB1 at low resolution molecular level. Of these, 31 patients and 99 controls also underwent “high resolution analysis” to define the HLA-DRB1*11 and DRB1*13 alleles. The haplotypes RAGE-374T, DRB1*04; RAGE-374T, DRB1*09; RAGE-374T, DRB1*11; RAGE-374A, DRB1*13; RAGE-429T, DRB1*04 and RAGE-429C, DRB1*11 were significantly more frequent in CFS patients, whereas RAGE-429C, DRB1*07 would seem protective. A significantly lower frequency of DRB1*1104 (5.4% vs 12.9% p=0.04, OR=0.39) and a significantly higher frequency of HLA-DRB1*1301 (13.0% vs 5.1% p=0.006, OR= 2.79) were found in CFS patients. A synergic effect was observed with RAGE polymorphism. The OR values strengthened in the following cis combinations: RAGE-374A, HLA-DRB1*1104 (OR=0.27) and RAGE-374A, HLA-DRB1*1301 (OR=6.23). HLA haplotypes rather than single alleles of RAGE or of DRB1 genes seem to be involved in CFS, probably including a subregion of major interest.

Excess of activating killer cell immunoglobulin‑like receptors and lack of HLA-Bw4 ligands: A two‑edged weapon in chronic fatigue syndrome

Chronic fatigue syndrome (CFS) is an inflammatory disease of unknown aetiology. Researchers have proposed infectious, neurological and immunological causes of this syndrome. Recently, the xenotropic murine leukemia virus-related virus was detected in 67% of patients with CFS in a US study. This observation is in agreement with one ascertained aspect of the disease: a decreased efficiency in NK cell lytic activity in CFS patients. Here, we analyzed the genomic polymorphism of killer cell immunoglobulin-like receptors (KIRs) and their HLA class I cognate ligands in patients with certified CFS. An excess of KIR3DS1 was found in CFS patients with respect to controls, as well as an increased frequency of the genotype missing KIR2DS5. Forty-four CFS patients and 50 controls also underwent genomic typing for the HLA-ligands. In the patients, a great proportion of KIR3DL1 and KIR3DS1 receptors were found to be missing their HLA-Bw4Ile80 binding motif. We hypothesize that an excess of KIR3DS1, combined with an excess of ligand-free KIR3DL1 and KIR3DS1 receptors, may hamper the clearance of a pathogen via NK cells, thus favouring the chronicity of the infection.

APJ polymorphisms in coronary artery disease patients with and without hypertension

Apelin is an endogenous peptide that increases cardiac inotropism through its APJ receptor. Certain findings indicate that the apelinergic system may have a pathophysiological role in cardiovascular disease and there is evidence showing the role of the apelinergic system in blood pressure regulation in vitro and in animal models. The role of the apelin-APJ system in cardiovascular physiology and its interaction with other neuroendocrine pathways has not been fully elucidated. However, the small number of reported studies indicates that apelin signaling may be involved in the regulation of blood pressure, cardiac contractile function, fluid balance, angiogenesis and inhibition of apoptosis. We evaluated the possible relationship between the G212A and A445C APJ polymorphisms and coronary artery disease (CAD) in Italian patients and in healthy controls by RFLP-PCR. We analyzed the allelic and genotypic frequencies of APJ polymorphisms in 664 patients (378 with hypertension) and 143 controls. There were no differences between allelic and genotypic frequencies in patients in respect to the controls for both polymorphisms analyzed. In the CAD population, there was an increased frequency of the G212 allele in patients with hypertension in respect to patients without hypertension. No differences were present in the two subgroups for the A445C polymorphism. Although the functional role of the G212A polymorphism has not yet been identified, it is possible to hypothesize that the presence of the A allele may cause a gain in function of the apelin/APJ system associated with a lower risk of hypertension.

Association between two polymorphisms in the HLA-G gene and angiographic coronary artery disease.

Atherosclerosis and related complications still represent the major cause of morbidity and mortality in industrialized countries. Therefore, it is particularly important to investigate the molecules involved in cardiac inflammation. Evidence exists showing that the human leukocyte antigen‑G (HLA-G) gene tissue expression and related protein physiological significance is influenced by two polymorphisms, rs16375 and rs1632933. In this study, allelic, genotypic and haplotypic frequencies of a 14-bp insertion/deletion (Ins/Del) (rs16375) and of rs1632933 polymorphisms of the HLA-G gene were investigated in 664 patients with coronary artery disease (CAD) and 345 matched controls by polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis and real-time PCR. The frequency of the Ins/Ins genotype was significantly higher in patients with CAD compared to the controls (P=0.018). After analysis of confounding variables, the results showed that the homozygous Ins/Ins was significantly and independently associated with the presence of angiographic CAD (odds ratio 2.09, 95% confidence interval 1.10-4.02, P=0.03). Our data demonstrate a new risk factor for this multifactorial inflammatory disease.

Microalbuminuria and sRAGE in High-Risk Hypertensive Patients Treated with Nifedipine/Telmisartan Combination Treatment: A Substudy of TALENT

Some antihypertensive drugs have also renoprotective and anti-inflammatory properties that go beyond their effect on blood pressure. It has been suggested that microalbuminuria and glomerular filtration rate (GFR) are associated with circulating levels of the soluble form of the receptor, sRAGE (soluble receptor for advanced glycation ends-products). In the present analysis, we used data from the TALENT study to evaluate soluble receptor for advanced glycation end-products (sRAGE) plasma levels in patients with hypertension and high-cardiovascular risk-treated nifedipine and telmisartan in combination. Treatment with nifedipine-telmisartan significantly decreased mean systolic and diastolic ambulatory blood pressure and resulted in a significant increase in sRAGE plasma concentrations after 24 weeks of therapy. We concluded that in hypertensive patients with early-stage renal disease, sRAGE concentrations are not influenced by either microalbuminuria or GFR. Long-term treatment with a combination of nifedipine-telmisartan may have a beneficial effect increasing sRAGE plasma levels, thus exerting an atheroprotective and anti-inflammatory activity.