Data for proteomic analysis of murine cardiomyocytic HL-1 cells treated with siRNA against tissue factor.

This data article is related to the research article entitled Proteomics of Tissue Factor silencing in cardiomyocytic cells reveals a new role for this coagulation factor in splicing machinery control by Lento et al. [1]. Tissue Factor (TF) is a key player in the coagulation cascade, but it has additional functions ranging from angiogenesis, tumour invasion and, in the heart, the maintenance of the integrity of cardiac cells. This article reports the nano-LC-MS(E) analysis of the cardiomyocytic HL-1 cell line proteome and describes the results obtained from a Gene Ontology analysis of those proteins affected by TF-gene silencing.

Proteomics of tissue factor silencing in cardiomyocytic cells reveals a new role for this coagulation factor in splicing machinery control.

It has long been known that Tissue Factor (TF) plays a role in blood coagulation and has a direct thrombotic action that is closely related to cardiovascular risk, but it is becoming increasingly clear that it has a much wider range of biological functions that range from inflammation to immunity. It is also involved in maintaining heart haemostasis and structure, and the observation that it is down-regulated in the myocardium of patients with dilated cardiomyopathy suggests that it influences cell-to-cell contact stability and contractility, and thus contributes to cardiac dysfunction. However, the molecular mechanisms underlying these coagulation-independent functions have not yet been fully elucidated. In order to analyse the influence of TF on the cardiomyocitic proteome, we used functional biochemical approaches incorporating label-free quantitative proteomics and gene silencing, and found that this provided a powerful means of identifying a new role for TF in regulating splicing machinery together with the expression of several proteins of the spliceosome, and mRNA metabolism with a considerable impact on cell viability. BIOLOGICAL SIGNIFICANCE: In this study, using quantitative proteomics and functional biochemical approaches, we define for the first time that, in addition to its primary role in blood coagulation, Tissue Factor also plays a novel role in regulating cell splicing machinery, with a relevant impact on cell survival. This new function may help to explain the wide range of biological activities of TF, and thus provide fruitful clues for developing new strategies for treating human diseases in which TF is dysregulated.

Corrigendum to "Data for proteomic analysis of murine cardiomyocytic HL-1 cells treated with siRNA against tissue factor" [Data Brief 3 (2015) 117-119].

[This corrects the article DOI: 10.1016/j.dib.2015.02.005.].

Proteomic analysis of plasma from patients undergoing coronary artery bypass grafting reveals a protease/antiprotease imbalance in favor of the serpin alpha1-antichymotrypsin.

We used proteomics to identify systematic changes in the plasma proteins of patients undergoing coronary artery bypass grafting (CABG) by means of cardiopulmonary bypass surgery. It is known that, after CABG, a complex systemic inflammatory responses ensues that favors the occurrence of adverse postoperative complications frequently recognizing inflammation itself and/or thrombosis as the underlying mechanism. We found a marked and persistent postoperative increase in the levels of the serpin-protease inhibitor alpha(1)-antichymotrypsin (alpha(1)-ACT) that fully maintains the inhibitory activity blunting its protease substrate cathepsin G. An intraoperative increase followed by a rapid decline in proteases activation was documented, accompanied by a substantial induction of leucine-rich-alpha-2-glycoprotein, a protein involved in neutrophilic granulocyte differentiation. Finally, a time-dependent alteration in the expression of haptoglobin, transthyretin, clusterin, and apoE was observed. In conclusion, we showed that after CABG, a protease/antiprotease imbalance occurs with early cathepsin G activation and a more delayed increase in alpha(1)-ACT. As cathepsin G is a serpin involved both in inflammation and coagulation activation, this confirms and expands the concept of a marked dysregulation of both inflammatory and hemostatic balances occurring after CABG. The pharmacologic modulation of this imbalance may be a new therapeutic target to reduce postoperative complications.

Proteomic analysis of human low-density lipoprotein reveals the presence of prenylcysteine lyase, a hydrogen peroxide-generating enzyme.

The molecular mechanisms underlying the relationship between low-density lipoprotein (LDL) and the risk of atherosclerosis are not clear. Therefore, detailed information on the protein composition of LDL may help to reveal its role in atherogenesis. Liquid-phase IEF has been used to resolve LDL proteins into well-defined fractions on the basis of pI, which improves the subsequent detection and resolution of low abundance proteins. Besides known LDL-associated proteins, this approach revealed the presence of proteins not previously described to reside in LDL, including prenylcysteine lyase (PCL1), orosomucoid, retinol-binding protein, and paraoxonase-1. PCL1, an enzyme crucial for the degradation of prenylated proteins, generates free cysteine, isoprenoid aldehyde and hydrogen peroxide. Addition of the substrate farnesylcysteine to lipoprotein resulted in a time-dependent generation of H(2)O(2) which was stronger in very low density lipoprotein (VLDL) than in LDL or HDL, reflecting the greater protein content of PCL1 in VLDL. Farnesol, a dead end inhibitor of the PCL1 reaction, reduced H(2)O(2) generation by VLDL. PCL1 is generated along with nascent lipoprotein, as shown by its presence in the lipoprotein secreted by HepG2 cells. The finding that an enzyme associated with atherogenic lipoproteins can itself generate an oxidant suggests that PCL1 may play a significant role in atherogenesis.

Oxidized proteins in plasma of patients with heart failure: role in endothelial damage.

BACKGROUND: Oxidative stress is increased in the failing heart, and this might contribute to the pathogenesis of myocardial remodelling and heart failure (HF). AIM: To identify the oxidized proteins in plasma of chronic HF patients and to evaluate their possible role in endothelial damage. METHODS: Plasma levels of oxidized proteins were measured by immunoassay and by analysis in albumin and immunoglobulin depleted plasma using a proteomic approach, in 40 HF patients and in 20 age-matched normal subjects. Analysis of the effects of proteins oxidized in vitro on human endothelial cell (EC) viability was also performed. RESULTS: Plasma levels of oxidized proteins were significantly higher in HF patients than in controls (p<0.01). We identified two proteins, alpha-1-antitrypsin and fibrinogen, which underwent oxidation. Oxidation of alpha-1-antitrypsin resulted in loss of its protease inhibitor activity, thus leading to EC death in the presence of elastase. Fibrinogen, when oxidized, became otherwise cytotoxic and induced apoptosis in EC. CONCLUSIONS: This study shows that plasma levels of oxidized proteins are increased in HF, and permitted the identification of two proteins, namely alpha-1-antitrypsin and fibrinogen, which underwent oxidation. In vitro results highlighted the potential role of oxidized proteins in the EC damage that occurs in HF.

Neurohormonal activation is associated with increased levels of plasma matrix metalloproteinase-2 in human heart failure.

AIMS: Development of heart failure depends on systemic and molecular abnormalities among which are the activation of neurohormonal systems and the increase of matrix metalloproteinases (MMPs). This study assessed the relationship between catecholamines and active MMPs in vivo in patients with severe congestive heart failure (CHF) and in vitro in human cardiac fibroblasts. METHODS AND RESULTS: Forty patients with CHF due to dilated cardiomyopathy, either idiopathic (n=20) or secondary to ischaemic heart disease (n=20), were compared with 20 healthy subjects. Plasma MMP-2 and MMP-9 activity, but not TIMP-2, were significantly higher in patients than in controls (median MMP-2, 270 vs. 214 ng/mL, P=0.006; MMP-9 16.3 vs. 8.7 ng/mL, P<0.0001). Similarly, noradrenaline, but not adrenaline, was significantly higher in patients (noradrenaline 645 vs. 157 pg/mL, P<0.0001; adrenaline 86.0 vs. 72.6 pg/mL, P=0.68). No difference in any parameter was observed between patient groups. The intra-group correlation between MMP-2 and noradrenaline was significant (r=0.33, P=0.01); indeed, noradrenaline appear to be a predictor of MMP-2. Moreover, this catecholamine increased MMP-2 in human cardiac fibroblasts. CONCLUSIONS: The positive correlation between noradrenaline and MMP-2 in severe CHF patients, together with the in vitro induction of MMP-2 by this catecholamine, suggests a potential biochemical link between noradrenaline and MMP-2.

Pentoxifylline prevents spontaneous brain ischemia in stroke-prone rats.

Anti-inflammatory properties of pentoxifylline (PTX) have recently been described. Spontaneously hypertensive stroke-prone rats (SHRSP) constitute an animal model that develops an inflammatory condition that precedes the appearance of brain abnormalities. The aim of the present investigation was to assess: 1) the efficacy of PTX treatment in protecting the neural system in SHRSP, and 2) how its anti-inflammatory properties might be involved in this effect. Male SHRSP fed with a permissive diet received no drug or PTX (100 or 200 mg/kg/day). Brain abnormalities detected by magnetic resonance imaging developed spontaneously in control rats after 42 +/- 3 days, whereas in rats treated with 100 mg/kg/day PTX, abnormalities developed in only 80% of the animals and only after 70 to 80 days. Treatment with a higher dose of PTX (200 mg/kg/day) completely protected the brain from abnormal development. The drug treatment prevented the accumulation of macrophages or CD4+ positive cells, the activation of glia in brain tissues, and the appearance of inflammatory proteins and thiobarbituric acid-reactive substances in body fluids. PTX treatment did induce a greater increase of serum tumor necrosis factor-alpha (TNF-alpha), but not of interleukin (IL)-1beta and IL-6 induced by in vivo administration of lipopolysaccharide (LPS), which suggests a protective role for TNF-alpha. PTX also exerted protective effects when it was administered after the first occurrence of proteinuria (>40 mg/day). These data indicate that PTX treatment dose-dependently prevents the occurrence of spontaneous brain damage by reducing inflammatory events. We also hypothesize that the increase of TNF-alpha by PTX treatment represents a protective mechanism in SHRSP.