Nebivolol: haemodynamic effects and clinical significance of combined beta-blockade and nitric oxide release.

Nebivolol is a third-generation beta-adrenergic receptor antagonist (beta-blocker) with high selectivity for beta(1)-adrenergic receptors. In addition, it causes vasodilatation via interaction with the endothelial L-arginine/nitric oxide (NO) pathway. This dual mechanism of action underlies many of the haemodynamic properties of nebivolol, which include reductions in heart rate and blood pressure (BP), and improvements in systolic and diastolic function. With respect to BP lowering, the NO-mediated effects cause a reduction in peripheral vascular resistance and an increase in stroke volume with preservation of cardiac output. Flow-mediated dilatation and coronary flow reserve are also increased during nebivolol administration. Other haemodynamic effects include beneficial effects on pulmonary artery pressure, pulmonary wedge pressure, exercise capacity and left ventricular ejection fraction. In addition, nebivolol does not appear to have adverse effects on lipid metabolism and insulin sensitivity like traditional beta-blockers. The documented beneficial haemodynamic effects of nebivolol are translated into improved clinical outcomes in patients with hypertension or heart failure. In patients with hypertension, the incidence of bradycardia with nebivolol is often lower than that with other currently available beta-blockers. This, along with peripheral vasodilatation and NO-induced benefits such as antioxidant activity and reversal of endothelial dysfunction, should facilitate better protection from cardiovascular events. In addition, nebivolol has shown an improved tolerability profile, particularly with respect to events commonly associated with beta-blockers, such as fatigue and sexual dysfunction. Data from SENIORS (Study of the Effects of Nebivolol Intervention on Outcomes and Rehospitalization in Seniors with Heart Failure) showed that significantly fewer nebivolol versus placebo recipients experienced the primary endpoint of all-cause mortality or cardiovascular hospitalization. The benefits of nebivolol therapy were shown to be cost effective. Thus, nebivolol is an effective and well tolerated agent with benefits over and above those of traditional beta-blockade because of its effects on NO release, which give it unique haemodynamic effects, cardioprotective activity and a good tolerability profile

Can we improve the treatment of congestion in heart failure?

INTRODUCTION: Dyspnoea and peripheral oedema, caused by fluid redistribution to the lungs and/or by fluid overload, are the main causes of hospitalization in patients with heart failure and are associated with poor outcomes. Treatment of fluid overload should relieve symptoms and have a neutral or favorable effect on outcomes. AREAS COVERED: We first consider the results obtained with furosemide administration, which is still the mainstay of treatment of congestion in patients with heart failure. We then discuss important shortcomings of furosemide treatment, including the development of resistance and side effects (electrolyte abnormalities, neurohormonal activation, worsening renal function), as well as the relationship of furosemide - and its doses - with patient prognosis. Finally, the results obtained with potential alternatives to furosemide treatment, including different modalities of loop diuretic administration, combined diuretic therapy, dopamine, inotropic agents, ultrafiltration, natriuretic peptides, vasopressin and adenosine antagonists, are discussed. EXPERT OPINION: Relief of congestion is a major objective of heart failure treatment but therapy remains based on the administration of furosemide, an agent that is often not effective and is associated with poor outcomes. The results of the few controlled studies aimed at the assessment of new treatments to overcome resistance to furosemide and/or to protect the kidney from its untoward effects have been mostly neutral. Better treatment of congestion in heart failure remains a major unmet need

Fibroblast growth factor 2-antagonist activity of a long-pentraxin 3-derived antiangiogenic pentapeptide.

Fibroblast growth factor-2 (FGF2) plays a major role in angiogenesis. The pattern recognition receptor long-pentraxin 3 (PTX3) inhibits the angiogenic activity of FGF2. To identify novel FGF2-antagonistic peptide(s), four acetylated (Ac) synthetic peptides overlapping the FGF2-binding region PTX3-(97-110) were assessed for their FGF2-binding capacity. Among them, the shortest pentapeptide Ac-ARPCA-NH(2) (PTX3-[100-104]) inhibits the interaction of FGF2 with PTX3 immobilized to a BIAcore sensorchip and suppresses FGF2-dependent proliferation in endothelial cells, without affecting the activity of unrelated mitogens. Also, Ac-ARPCA-NH(2) inhibits angiogenesis triggered by FGF2 or by tumorigenic FGF2-overexpressing murine endothelial cells in chick and zebrafish embryos, respectively. Accordingly, the peptide hampers the binding of FGF2 to Chinese Hamster ovary cells overexpressing the tyrosine-kinase FGF receptor-1 (FGFR1) and to recombinant FGFR1 immobilized to a BIAcore sensorchip without affecting heparin interaction. In all the assays the mutated Ac-ARPSA-NH(2) peptide was ineffective. In keeping with the observation that hydrophobic interactions dominate the interface between FGF2 and the FGF-binding domain of the Ig-like loop D2 of FGFR1, amino acid substitutions in Ac-ARPCA-NH(2) and saturation transfer difference-nuclear magnetic resonance analysis of its mode of interaction with FGF2 implicate the hydrophobic methyl groups of the pentapeptide in FGF2 binding. These results will provide the basis for the design of novel PTX3-derived anti-angiogenic FGF2 antagonists

Worsening renal function in patients hospitalised for acute heart failure: clinical implications and prognostic significance.

BACKGROUND: Renal function is a powerful prognostic variable in patients with heart failure (HF). Hospitalisations for acute HF (AHF) may be associated with further worsening of renal function (WRF). METHODS AND RESULTS: We analysed the clinical significance of WRF in 318 consecutive patients admitted at our institute for AHF. WRF was defined as the occurrence, at any time during the hospitalisation, of both a > or =25% and a > or =0.3 mg/dL increase in serum creatinine (s-Cr) from admission (WRF-Abs-%). RESULTS: Patients were followed for 480+/-363 days. Fifty-three patients (17%) died and 132 (41%) were rehospitalised for HF. WRF-Abs-% occurred in 107 (34%) patients. At multivariable survival analysis, WRF-Abs-% was an independent predictor of death or HF rehospitalisation (adjusted HR, 1.47; 95%CI, 1.13-1.81; p=0.024). The independent predictors of WRF-Abs-%, evaluated using multivariable logistic regression, were history of chronic kidney disease (p=0.002), LV ejection fraction (p=0.012), furosemide daily dose (p=0.03) and NYHA class (p=0.05) on admission. CONCLUSION: WRF is a frequent finding in patients hospitalised for AHF and is associated with a poor prognosis. Severity of HF and daily furosemide dose are the most important predictors of the occurrence of WRF

Molecular Interaction Studies of HIV-1 Matrix Protein p17 and Heparin: IDENTIFICATION OF THE HEPARIN-BINDING MOTIF OF p17 AS A TARGET FOR THE DEVELOPMENT OF MULTITARGET ANTAGONISTS

Once released by HIV cells, p17 binds heparan sulfate proteoglycans (HSPGs) and CXCR1 on leukocytes causing their dysfunction. By exploiting an approach integrating computational modeling, site-directed mutagenesis of p17, chemical desulfation of heparin, and surface plasmon resonance, we characterized the interaction of p17 with heparin, a HSPG structural analog, and CXCR1. p17 binds to heparin with an affinity (Kd 190 nM) that is similar to those of other heparin-binding viral proteins. Two stretches of basic amino acids (basic motifs) are present in p17 N and C termini. Neutralization (Arg3Ala substitution) of the N-terminal, but not of the C-terminal basic motif, causes the loss of p17 heparin-binding capacity. The N-terminal heparin-binding motif of p17 partially overlaps the CXCR1-binding domain. Accordingly, its neutralization prevents also p17 binding to the chemochine receptor. Competition experiments demonstrated that free heparin and heparan sulfate (HS), but not selectively 2-O-, 6-O-, and N-O desulfated heparins, prevent p17 binding to substrate-immobilized heparin, indicating that the sulfate groups of the glycosaminoglycan mediate p17 interaction. Evaluation of the p17 antagonist activity of a panel of biotechnological heparins derived by chemical sulfation of the Escherichia coli K5 polysaccharide revealed that the highlyN,O-sulfated derivative prevents the binding of p17 to both heparin and CXCR1, thus inhibiting p17-driven chemotactic migration of human monocytes with an efficiency that is higher than those of heparin and HS. Here, we characterized at a molecular level the interaction of p17 with its cellular receptors, laying the basis for the development of heparin-mimicking p17 antagonists

Is worsening renal function an ominous prognostic sign in patients with acute heart failure? The role of congestion and its interaction with renal function.

BACKGROUND: Worsening renal function (WRF), traditionally defined as an increase in serum creatinine levels ≥0.3 mg/dL, is a frequent finding in patients with acute heart failure (AHF) and has been associated with poorer outcomes in some but not all studies. We hypothesized that these discrepancies may be caused by the interaction between WRF and congestion in AHF patients. METHODS AND RESULTS: We measured serum creatinine levels on a daily basis during the hospitalization and assessed the persistence of signs of congestion at discharge in 599 consecutive patients admitted at our institute for AHF. They had a postdischarge mortality and mortality or AHF readmission rates of 13% and 43%, respectively, after 1 year. Patients were subdivided into 4 groups according to the development or not of WRF and the persistence of ≥1 sign of congestion at discharge. Patients with WRF and no congestion had similar outcomes compared with those with no WRF and no congestion, whereas the risk of death or of death or AHF readmission was increased in the patients with persistent congestion alone and in those with both WRF and congestion (hazard ratio, 5.35; 95% confidence interval, 3.0-9.55 at univariable analysis; hazard ratio, 2.44; 95% confidence interval, 1.24-4.18 at multivariable analysis for mortality; hazard ratio, 2.14; 95% confidence interval, 1.39-3.3 at univariable analysis; and hazard ratio, 1.39; 95% confidence interval, 0.88-2.2 at multivariable analysis for mortality and rehospitalizations). CONCLUSIONS: WRF alone, when detected using serial serum creatinine measurements, is not an independent determinant of outcomes in patients with AHF. It has an additive prognostic value when it occurs in patients with persistent signs of congestion

Antiangiogenic activity of semisynthetic biotechnological heparins: low-molecular-weight-sulfated Escherichia coli K5 polysaccharide derivatives as fibroblast growth factor antagonists.

OBJECTIVE: Low-molecular-weight heparin (LMWH) exerts antitumor activity in clinical trials. The K5 polysaccharide from Escherichia coli has the same structure as the heparin precursor. Chemical and enzymatic modifications of K5 polysaccharide lead to the production of biotechnological heparin-like compounds. We investigated the fibroblast growth factor-2 (FGF2) antagonist and antiangiogenic activity of a series of LMW N,O-sulfated K5 derivatives. METHODS AND RESULTS: Surface plasmon resonance analysis showed that LMW-K5 derivatives bind FGF2, thus inhibiting its interaction with heparin immobilized to a BIAcore sensor chip. Interaction of FGF2 with tyrosine-kinase receptors (FGFRs), heparan sulfate proteoglycans (HSPGs), and alpha(v)beta3 integrin is required for biological response in endothelial cells. Similar to LMWH, LMW-K5 derivatives abrogate the formation of HSPG/FGF2/FGFR ternary complexes by preventing FGF2-mediated attachment of FGFR1-overexpressing cells to HSPG-bearing cells and inhibit FGF2-mediated endothelial cell proliferation. However, LMW-K5 derivatives, but not LMWH, also inhibit FGF2/alpha(v)beta3 integrin interaction and consequent FGF2-mediated endothelial cell sprouting in vitro and angiogenesis in vivo in the chick embryo chorioallantoic membrane. CONCLUSIONS: LMW N,O-sulfated K5 derivatives affect both HSPG/FGF2/FGFR and FGF2/alpha(v)beta3 interactions and are endowed with FGF2 antagonist and antiangiogenic activity. These compounds may provide the basis for the design of novel LMW heparin-like angiostatic compounds

B cell autoimmunity and bone damage in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic immune-inflammatory disease associated with significant bone damage. Pathological bone remodeling in RA is primarily driven by persistent inflammation. Indeed, pro-inflammatory cytokines stimulate the differentiation of bone-resorbing osteoclasts and, in parallel, suppress osteoblast function, resulting in net loss of bone. Abating disease activity thus remains the major goal of any treatment strategy in patients with RA. Autoantibody-positive patients, however, often show a rapidly progressive destructive course of the disease, disproportionate to the level of inflammation. The epidemiological association between RA-specific autoantibodies, in particular anti-citrullinated protein autoantibodies, and poor structural outcomes has recently found mechanistic explanation in the multiple roles that B cells play in bone remodeling. In this review, we will summarize the substantial progress that has been made in deciphering how B cells and autoantibodies negatively impact on bone in the course of RA, through both inflammation-dependent and independent mechanisms

Histopathology of the synovial tissue : perspectives for biomarker development in chronic inflammatory arthritides

The histopathological and molecular analysis of the synovial tissue has contributed to fundamental advances in our comprehension of arthritis pathogenesis and of the mechanisms of action of currently available treatments. On the other hand, its exploitation in clinical practice for diagnostic or prognostic purposes as well as for the prediction of treatment response to specific disease-modifying anti-rheumatic drugs is still limited. In this review, we present an overview of recent advances in the field of synovial tissue research with specific reference to the methods for synovial tissue collection, approaches to synovial tissue analysis and current perspectives for the exploitation of synovial tissue-derived biomarkers in chronic inflammatory arthritides