Marina Borro

Cardiac resynchronization therapy increases plasma levels of the endogenous inotrope apelin.

Cardiac resynchronization therapy (CRT) has been introduced to treat drug refractory chronic heart failure (CHF). Apelin, the endogenous ligand of the APJ receptor, is under evaluation for its potential role in human CHF pathophysiology. This study aims to assess whether biventricular pacing affects plasma apelin levels in patients with severe CHF.

Esculentin‐1b(1–18) – a membrane‐active antimicrobial peptide that synergizes with antibiotics and modifies the expression level of a limited number of proteins in Escherichia coli

Antimicrobial peptides constitute one of the main classes of molecular weapons deployed by the innate immune system of all multicellular organisms to resist microbial invasion. A good proportion of all antimicrobial peptides currently known, numbering hundreds of molecules, have been isolated from frog skin. Nevertheless, very little is known about the effect(s) and the mode(s) of action of amphibian antimicrobial peptides on intact bacteria, especially when they are used at subinhibitory concentrations and under conditions closer to those encountered in vivo. Here we show that esculentin‐1b(1–18) [Esc(1–18)] (GIFSKLAGKKLKNLLISG‐NH2), a linear peptide encompassing the first 18 residues of the full‐length esculentin‐1b, rapidly kills Escherichia coli at the minimal inhibitory concentration. The lethal event is concomitant with the permeation of the outer and inner bacterial membranes. This is in contrast to what is found for many host defense peptides, which do not destabilize membranes at their minimal inhibitory concentrations. Importantly, proteomic analysis revealed that Esc(1–18) has a limited ability to modify the bacterium’s protein expression profile, at either bactericidal or sublethal concentrations. To the best of our knowledge, this is the first report on the effects of an antimicrobial peptide from frog skin on the proteome of its bacterial target, and underscores the fact that the bacterial membrane is the major target for the killing mechanism of Esc(1–18), rather than intracellular processes.

Plasma osteopontin reveals left ventricular reverse remodelling following cardiac resynchronization therapy in heart failure

BACKGROUND Cardiac resynchronization therapy (CRT) promotes left ventricular (LV) reverse remodelling and affects myocardial collagen turnover in heart failure (HF) patients. Osteopontin (OPN) is a matrix glycoprotein required for the activation of fibroblasts upon TGF-β1 stimulation. In humans, plasma OPN and OPN-expressing lymphocytes correlate with the severity of HF. We sought to evaluate whether plasma OPN and TGF-β1 reflect LV reverse remodelling following CRT. METHODS Eighteen patients (12 men, mean age 65 ± 11 years) undergoing CRT were studied. Patients underwent baseline clinical and echocardiographic evaluation, and assessment of plasma OPN and TGF-β1. The evaluation was repeated 8.5 ± 4 months after device implantation. Eight healthy age- and sex-matched subjects served as controls. RESULTS In HF patients, baseline plasma OPN and TGF-β1 were higher as compared to control subjects (OPN: 99 ± 48 vs 59 ± 22 ng/ml; p<0.05; TGF-β1: 15.9 ± 8.0 vs 9.3 ± 5.6 ng/ml; p<0.05). At follow-up, 12 patients responded to CRT and showed LV reverse remodelling, whereas 6 did not. Plasma OPN decreased in CRT responders (108 ± 47 vs 84 ± 37 ng/ml; p=0.03) and increased in non-responders (79 ± 58 vs 115 ± 63 ng/ml; p<0.01). TGF-β1 showed a trend towards reduction in responders (17.5 ± 8.7 vs 10.2 ± 8.9 ng/ml; p=0.08) and was unchanged in non-responders. A significant correlation (r=-0.56; p=0.01) was found between relative changes of LVESV and plasma OPN. CONCLUSIONS CRT-induced LV reverse remodelling is reflected by changes in plasma OPN. Circulating OPN may represent a marker of LV dilation/impairment and an indicator of the response to HF therapies promoting LV reverse remodelling.

Genetic polymorphisms related to efficacy and overuse of triptans in chronic migraine

Migraine is a common type of headache and its most severe attacks are usually treated with triptans, the efficacy of which is extremely variable. Several SNPs in genes involved in metabolism and target mechanisms of triptans have been described. To define an association between genetic profile and triptan response, we classified a migrainous population on the basis of triptan response and characterized it for polymorphisms in the genes coding for monoamine oxidase A, G protein β3 and the cytochrome CYP1A2. Analysis of the association between genotypic and allelic frequencies of the analyzed SNPs and the grade of response to triptan administration showed a significant correlation for MAOA uVNTR polymorphism. Further stratification of patients in abuser and non-abuser groups revealed a significant association with triptan overuse and, within the abusers, with drug response to the CYP1A2*1F variant.

Response of Serum Proteome in Patients Undergoing Infrarenal Aortic Aneurysm Repair

Background:Postoperative organ dysfunction in conventional surgery for abdominal aortic aneurysm (AAA) is associated with a complex inflammatory reaction, with activation of coagulation and fibrinolysis. A prospective,observational study was performed to define the complex plasma proteomic changes after AAA repair and to identify factor(s) that may affect myocardial function in uncomplicated procedures. Methods:Ten patients undergoing infrarenal AAA repair were investigated. Eight subjects subjected to major abdominal surgery served as controls. Hemodynamic changes were continuously monitored by using the pressure recording analytical method technique. The time course of plasma proteins was investigated after induction of anesthesia and at different times after surgery (6 h, 12 h, 24 h, 36 h) by using two-dimensional difference gel electrophoresis, matrix-assisted laser desorption/ionization-time of flight mass spectrometry, and Western blot. The effects of plasma on the functional properties of isolated rat ventricular myocytes were also investigated. Results:In AAA patients alone, 18 spots were found to change more than two-fold in expression level, spot identification revealing an increased thrombin generation 6 h after surgery. At the same time cardiac cycle efficiency significantly reduced versus baseline (–0.5 ± 0.9 vs. 0.18 ± 0.3 in AAA patients, P < 0.01; 0.4 ± 0.1 vs. 0.2 ± 0.3 in control surgery, not significant; P < 0.01 group × time interaction at ANOVA). Plasma obtained 6 h after AAA surgery dose-dependently inhibited contractile function of control rat myocytes (percent shortening fell by 51% with 10% of AAA plasma and was abolished with 20% of AAA plasma, P < 0.001 for both). The inhibitory response was abolished by thrombin antagonism. Conclusions:These findings show for the first time the possible role of thrombin generation within the complex activation of inflammatory response in causing hemodynamic instability in the early postoperative period after AAA surgery.

Proteomic analysis of peripheral T lymphocytes, suitable circulating biosensors of strictly related diseases

T lymphocytes and/or their subpopulations from peripheral blood may represent molecular sensors to be used for the evaluation of gene expression modification in physiological and pathological conditions, providing a unique and easily available biological model for integrated studies of gene expression in humans. In this study, a proteomic approach was applied to evaluate the association between changes in T cell protein expression patterns and specific diseased conditions. In particular, two hyperandrogenic syndromes were studied, sharing many clinical and biochemical signs: polycystic ovary syndrome (PCOS) and congenital adrenal hyperplasia (CAH). Comparison of proteomic maps of T lymphocytes derived from patients affected by PCOS or CAH with those derived from healthy subjects showed that 14 proteins are expressed differentially in both PCOS and CAH, 15 exclusively in PCOS and 35 exclusively in CAH. Seventeen of these proteins have been identified by mass spectrometry analysis. Furthermore, proteomic data mining by hierarchical clustering was performed, highlighting T lymphocytes competence as a living biosensor system.

Sequence of a gene from Bombina orientalis coding for the antimicrobial peptide BLP-7

The structure of a gene coding for bombinin-like peptides (BLP) in Bombina orientalis was determined. It comprises two exons separated by a 1337 bp intron. Exon 1 codes for the signal peptide, while exon 2 contains the genetic information for BLP-7 and a bombinin H-type peptide (GH-2). The promoter region contains putative recognition sites for nuclear factors, such as NF-IL6 and NF-kappaB. The analysis of the structure of this gene, compared with that of the previously reported BLP-3 gene sequence, suggests the occurrence of a gene duplication event, rather than an alternative splicing mechanism, which leads to the generation of both inter- and intra-families variability in this class of cytolytic peptides. Furthermore, chromosome walking analysis indicates that this gene family is not densely clustered.

Low prostate concentration of lycopene is associated with development of prostate cancer in patients with high-grade prostatic intraepithelial neoplasia

Prostate cancer (PC) is a frequent male malignancy and represents the second most diagnosed cancer in men. Since pre-cancerous lesions, i.e., the high-grade prostatic intraepithelial neoplasia (HGPIN), can be detected years before progression to PC, early diagnosis and chemoprevention are targeted strategies to reduce PC rates. Animal studies have shown that lycopene, a carotenoid contained in tomatoes, is a promising candidate for the chemoprevention of PC. However, its efficacy in humans remains controversial. The present study aimed to investigate the relevance of plasma and prostate concentration of lycopene after a lycopene-enriched diet in patients diagnosed with HGPIN. Thirty-two patients diagnosed with HGPIN were administered a lycopene-enriched diet (20–25 mg/day of lycopene; through 30 g/day of triple concentrated tomato paste) for 6 months. A 6-month follow-up prostate biopsy assessed progression to PC. Patients were classified into three groups according to the histopathological features of the 6-month follow-up biopsy results: prostatitis; HGPIN and PC. PSA and plasma lycopene levels were measured before and after the dietary lycopene supplementation. Prostatic lycopene concentration was only assessed after the supplementation diet. Only prostatic lycopene concentration showed significant differences between the three groups (p = 0.03). Prostatic lycopene concentration below a 1 ng/mg threshold was associated with PC at 6-month follow-up biopsy (p = 0.003). We observed no overall benefits from a 6-month lycopene supplementation, as the rate of HGPIN progression to PC in our population (9/32, 28%) was similar to rates reported in the literature. Baseline PSA levels also showed no significant changes after a lycopene-enriched diet. Our findings point to prostatic lycopene concentration as a promising biomarker of PC. Further prospective longitudinal studies are needed to assess the prognostic role of prostatic lycopene in PC.

Gene polymorphisms involved in triptans pharmacokinetics and pharmacodynamics in migraine therapy

Importance of the field: Migraine is a debilitating and painful neurological disorder affecting millions of people worldwide and often worsened by chronification. Triptans represent a powerful pharmacological resource in migraine management; nevertheless, a significant portion of treated patients do not obtain consistent pain relief through triptans. Pharmacogenomics may offer a new way to rationalise triptans administration, based on characterisation of the individual genomic profile. Areas covered in this review: The review summarises the results of association studies between polymorphisms in genes involved in the kinetics and dynamics of triptans, and clinical response to them in migraineurs. What the reader will gain: A summary of data available at present from genetic studies in the field of triptan therapy in migraine, and a picture of the difficulties facing research into the pharmacogenomics of triptans. Take home message: Pharmacogenomic studies of triptans suggest that some genetic determinants influence drug response, but the complexity of the field calls for application of a systematic approach to genetic association studies, allowing identification of a therapy response prediction panel with adequate predictive power.

Proteomic profiles in hyperandrogenic syndromes.

Background: Polycystic ovary syndrome (PCOS) and congenital adrenal hyperplasia (CAH) represent the most common causes of hyperandrogenism. Although the etiopathogeneses of these syndromes are different, they share many clinical and biochemical signs, such as hirsutism, acne, and chronic anovulation. Experimental data have shown that peripheral T-lymphocytes function as molecular sensors, being able to record molecular signals either at staminal and mature cell levels, or hormones at systemic levels. Methods: Twenty PCOS women and 10 CAH with 21-hydroxylase deficiency, aged between 18–35 yr, were studied. T-cells purified from all patients and 20 healthy donors have been analyzed by 2-dimensional gel electrophoresis. Silver-stained proteomic map of each patient was compared with a control map obtained by pooling protein samples of the 20 healthy subjects. Results: Spots of interest were identified by peptide mass fingerprint. Computer analysis evidenced several peptidic spots significantly modulated in all patients examined. Some proteins were modulated in both syndromes, others only in PCOS or in CAH. These proteins are involved in many physiological processes as the functional state of immune system, the regulation of the cytoskeleton structure, the oxidative stress, the coagulation process, and the insulin resistance. Conclusion: Identification of the physiological function of these proteins could help to understand ethiopathogenetic mechanisms of hyperandrogenic syndromes and its complications.