Sex-dependent expression of galectin-1, a cardioprotective ß-galactoside-binding lectin, in human calcific aortic stenosis.

We aimed to analyze sex-related differences in galectin-1 (Gal-1), a ß-galactoside-binding lectin, in aortic stenosis (AS) and its association with the inflammatory and fibrocalcific progression of AS. Gal-1 was determined in serum and aortic valves (AVs) from control and AS donors by western blot and immunohistochemistry. Differences were validated by ELISA and qPCR in AS samples. In vitro experiments were conducted in primary cultured valve interstitial cells (VICs). Serum Gal-1 was not different neither between control and AS nor between men and women. There was no association between circulating and valvular Gal-1 levels. The expression of Gal-1 in stenotic AVs was higher in men than women, even after adjusting for confounding factors, and was associated with inflammation, oxidative stress, extracellular matrix remodeling, fibrosis, and osteogenesis. Gal-1 (LGALS1) mRNA was enhanced within fibrocalcific areas of stenotic AVs, especially in men. Secretion of Gal-1 was up-regulated over a time course of 2, 4, and 8 days in men's calcifying VICs, only peaking at day 4 in women's VICs. In vitro, Gal-1 was associated with similar mechanisms to those in our clinical cohort. ß-estradiol significantly up-regulated the activity of an LGALS1 promoter vector and the secretion of Gal-1, only in women's VICs. Supplementation with rGal-1 prevented the effects elicited by calcific challenge including the metabolic shift to glycolysis. In conclusion, Gal-1 is up-regulated in stenotic AVs and VICs from men in association with inflammation, oxidative stress, matrix remodeling, and osteogenesis. Estrogens can regulate Gal-1 expression with potential implications in post-menopause women. Exogenous rGal-1 can diminish calcific phenotypes in both women and men.

Atherosclerosis and Other Related-Arterial Diseases.

Cardiovascular diseases (CVD) are a major cause of morbidity and mortality worldwide, accounting for more than 17 million deaths each year [...].

Combined Immunoglobulin Free Light Chains Are Novel Predictors of Cardiovascular Events in Patients With Abdominal Aortic Aneurysm.

OBJECTIVE: Abdominal aortic aneurysm (AAA) is characterised by the presence of B cells and immunoglobulins in the aortic wall, mainly in the adventitia. Kappa (κ) and lambda (λ) free light chains (FLCs) are produced from B cells during immunoglobulin synthesis. This study investigated the presence and prognostic value of combined FLCs (cFLCs or summed κ and λ) in patients with AAA. METHODS: cFLCs were analysed by a turbidimetric specific assay in tissue conditioned media from AAA samples (n = 34) compared with healthy aortas (n = 34) from France and in plasma samples from patients with AAA (n = 434) and age matched controls (n = 104) selected from the Viborg Vascular (VIVA) AAA screening trial in Denmark. t test, logistic regression, and Cox regression were used to test whether plasma cFLCs serve as a marker for AAA presence and whether cFLCs were predictive of death, major adverse cardiovascular events (MACE), or major adverse lower limb events (MALE). RESULTS: Increased cFLC levels were detected in the AAA adventitial layer compared with the AAA medial layer and healthy media layer (13.65 ± 3.17 vs. 6.57 ± 1.01 vs. 0.49 ± 0.09 mg/L, respectively, p < .050). The upper tertile of plasma cFLCs was independently associated with AAA presence after correcting for confounders (odds ratio [OR] 7.596, 95% confidence intervals [CI] 3.117 - 18.513; p < .001). Of 434 patients with AAA, 89 (20.5%) died, 104 (24.0%) suffered MACE, and 63 (14.5%) suffered MALE, during a five year follow up. In univariable analysis, the cFLC upper tertile was associated with a higher risk of death, MACE, and MALE (p < .001 for all). After adjustment for confounders, cFLCs remained an independent predictor of all cause mortality (hazard ratio [HR] 4.310, 95% CI 2.157 - 8.609; p < .001), MACE (HR 2.153, 95% CI 1.218 - 3.804; p = .008), or MALE (HR 3.442, 95% CI 1.548 - 7.652; p = .002) for those in the upper tertile. CONCLUSION: Increased cFLCs are observed in adventitial tissue of patients with AAA, indicating local activation of B cells. Plasma cFLC levels are an independent predictor of death, MACE, and MALE in patients with AAA.

CD163 deficiency increases foam cell formation and plaque progression in atherosclerotic mice.

Atherosclerosis is an inflammatory disease characterized by the accumulation of macrophages in the vessel wall. Macrophages depend on their polarization to exert either pro-inflammatory or anti-inflammatory effects. Macrophages of the anti-inflammatory phenotype express high levels of CD163, a scavenger receptor for the hemoglobin-haptoglobin complex. CD163 can also bind to the pro-inflammatory cytokine TWEAK. Using ApoE-deficient or ApoE/CD163 double-deficient mice we aim to investigate the involvement of CD163 in atherosclerosis development and its capacity to neutralize the TWEAK actions. ApoE/CD163 double-deficient mice displayed a more unstable plaque phenotype characterized by an increased lipid and macrophage content, plaque size, and pro-inflammatory cytokine expression. In vitro experiments demonstrated that the absence of CD163 in M2-type macrophages-induced foam cell formation through upregulation of CD36 expression. Moreover, exogenous TWEAK administration increased atherosclerotic lesion size, lipids, and macrophages content in ApoE-/- /CD163-/- compared with ApoE-/- /CD163+/+ mice. Treatment with recombinant CD163 was able to neutralize the proatherogenic effects of TWEAK in ApoE/CD163 double-deficient mice. Recombinant CD163 abolished the pro-inflammatory actions of TWEAK on vascular smooth muscle cells, decreasing NF-kB activation, cytokines and metalloproteinases expression, and macrophages migration. In conclusion, CD163-expressing macrophages serve as a protective mechanism to prevent the deleterious effects of TWEAK on atherosclerotic plaque development and progression.

The TNF-like weak inducer of the apoptosis/fibroblast growth factor-inducible molecule 14 axis mediates histamine and platelet-activating factor-induced subcutaneous vascular leakage and anaphylactic shock.

BACKGROUND: Anaphylaxis includes mast cell (MC) activation, but less is known about downstream mechanisms (ie, vascular permeability controlled by endothelial cells [ECs]). The TNF-like weak inducer of apoptosis (TWEAK) and its sole receptor, fibroblast growth factor-inducible molecule 14 (Fn14), belong to the TNF superfamily and are involved in proinflammatory responses. OBJECTIVE: We sought to investigate the role of TWEAK/Fn14 axis in anaphylaxis. METHODS: In vivo vascular permeability and mouse models of passive systemic anaphylaxis (PSA) and active systemic anaphylaxis were applied to wild-type (WT), TWEAK- and Fn14-deficient mice (TWEAK-/- and Fn14-/-, respectively). Primary bone marrow-derived mast cells (BMMCs) and ECs from WT and Fn14-/- or TWEAK-/- mice were studied. The TWEAK/Fn14 axis was also investigated in human samples. RESULTS: Mice with PSA and active systemic anaphylaxis had increased Fn14 and TWEAK expression in lung tissues and increased serum soluble TWEAK concentrations. TWEAK and Fn14 deficiencies prevent PSA-related symptoms, resulting in resistance to decreased body temperature, less severe reactions, and maintained physical activity. Numbers of MCs after PSA are similar between genotypes in different tissue regions, such as ear skin and the trachea, tongue, peritoneum, lungs, and bone marrow. Moreover, in vitro studies revealed no differences in degranulation or mediator release between WT and Fn14-/- BMMCs after IgE-FcεRI stimulation. In vivo and in vitro histamine and platelet-activating factor administration increases Fn14 receptor expression in lungs and ECs. Moreover, Fn14 deficiency in ECs maintained in vitro impermeability when stimulated by mediators or activated BMMCs but not by TWEAK-/- BMMCs, indicating that Fn14 is crucial for endothelial barrier function. TWEAK/Fn14 deletion or TWEAK-blocking antibody prevented histamine/platelet-activating factor-induced vascular subcutaneous permeability. Circulating soluble TWEAK levels were increased in patients with anaphylaxis, and plasma from those patients increased Fn14 expression in ECs. CONCLUSION: The TWEAK/Fn14 axis participates in anaphylactic reactions. Inhibition of TWEAK/Fn14 interaction could be efficacious in anaphylaxis therapy.

Cellular Crosstalk between Endothelial and Smooth Muscle Cells in Vascular Wall Remodeling.

Pathological vascular wall remodeling refers to the structural and functional changes of the vessel wall that occur in response to injury that eventually leads to cardiovascular disease (CVD). Vessel wall are composed of two major primary cells types, endothelial cells (EC) and vascular smooth muscle cells (VSMCs). The physiological communications between these two cell types (EC-VSMCs) are crucial in the development of the vasculature and in the homeostasis of mature vessels. Moreover, aberrant EC-VSMCs communication has been associated to the promotor of various disease states including vascular wall remodeling. Paracrine regulations by bioactive molecules, communication via direct contact (junctions) or information transfer via extracellular vesicles or extracellular matrix are main crosstalk mechanisms. Identification of the nature of this EC-VSMCs crosstalk may offer strategies to develop new insights for prevention and treatment of disease that curse with vascular remodeling. Here, we will review the molecular mechanisms underlying the interplay between EC and VSMCs. Additionally, we highlight the potential applicable methodologies of the co-culture systems to identify cellular and molecular mechanisms involved in pathological vascular wall remodeling, opening questions about the future research directions.

Impaired HDL (High-Density Lipoprotein)-Mediated Macrophage Cholesterol Efflux in Patients With Abdominal Aortic Aneurysm-Brief Report.

Objective- The ability of HDL (high-density lipoprotein) to promote macrophage cholesterol efflux is considered the main HDL cardioprotective function. Abdominal aortic aneurysm (AAA) is usually characterized by cholesterol accumulation and macrophage infiltration in the aortic wall. Here, we aim to evaluate the composition of circulating HDL particles and their potential for promoting macrophage cholesterol efflux in AAA subjects. Approach and Results- First, we randomly selected AAA and control subjects from Spain. The AAA patients in the Spanish cohort showed lower plasma apoA-I levels concomitantly associated with low levels of plasma HDL cholesterol and the amount of preß-HDL particles. We determined macrophage cholesterol efflux to apoB-depleted plasma, which contains mature HDL, preß-HDL particles and HDL regulatory proteins. ApoB-depleted plasma from AAA patients displayed an impaired ability to promote macrophage cholesterol efflux. Next, we replicated the experiments with AAA and control subjects derived from Danish cohort. Danish AAA patients also showed lower apoA-I levels and a defective HDL-mediated macrophage cholesterol efflux. Conclusions- AAA patients show impaired HDL-facilitated cholesterol removal from macrophages, which could be mechanistically linked to AAA.

Increased galectin-3 levels are associated with abdominal aortic aneurysm progression and inhibition of galectin-3 decreases elastase-induced AAA development.

Abdominal aortic aneurysm (AAA) evolution is unpredictable and no specific treatment exists for AAA, except surgery to prevent aortic rupture. Galectin-3 has been previously associated with CVD, but its potential role in AAA has not been addressed. Galectin-3 levels were increased in the plasma of AAA patients (n=225) compared with the control group (n=100). In addition, galectin-3 concentrations were associated with the need for surgical repair, independently of potential confounding factors. Galectin-3 mRNA and protein expression were increased in human AAA samples compared with healthy aortas. Experimental AAA in mice was induced via aortic elastase perfusion. Mice were treated intravenously with the galectin-3 inhibitor modified citrus pectin (MCP, 10 mg/kg, every other day) or saline. Similar to humans, galectin-3 serum and aortic mRNA levels were also increased in elastase-induced AAA mice compared with control mice. Mice treated with MCP showed decreased aortic dilation, as well as elastin degradation, vascular smooth muscle cell (VSMC) loss, and macrophage content at day 14 postelastase perfusion compared with control mice. The underlying mechanism(s) of the protective effect of MCP was associated with a decrease in galectin-3 and cytokine (mainly CCL5) mRNA and protein expression. Interestingly, galectin-3 induced CCL5 expression by a mechanism involving STAT3 activation in VSMC. Accordingly, MCP treatment decreased STAT3 phosphorylation in elastase-induced AAA. In conclusion, increased galectin-3 levels are associated with AAA progression, while galectin-3 inhibition decreased experimental AAA development. Our data suggest the potential role of galectin-3 as a therapeutic target in AAA.

Oxidative Stress in Human Atherothrombosis: Sources, Markers and Therapeutic Targets.

Atherothrombosis remains one of the main causes of morbidity and mortality worldwide. The underlying pathology is a chronic pathological vascular remodeling of the arterial wall involving several pathways, including oxidative stress. Cellular and animal studies have provided compelling evidence of the direct role of oxidative stress in atherothrombosis, but such a relationship is not clearly established in humans and, to date, clinical trials on the possible beneficial effects of antioxidant therapy have provided equivocal results. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is one of the main sources of reactive oxygen species (ROS) in human atherothrombosis. Moreover, leukocyte-derived myeloperoxidase (MPO) and red blood cell-derived iron could be involved in the oxidative modification of lipids/lipoproteins (LDL/HDL) in the arterial wall. Interestingly, oxidized lipoproteins, and antioxidants, have been analyzed as potential markers of oxidative stress in the plasma of patients with atherothrombosis. In this review, we will revise sources of ROS, focusing on NADPH oxidase, but also on MPO and iron. We will also discuss the impact of these oxidative systems on LDL and HDL, as well as the value of these modified lipoproteins as circulating markers of oxidative stress in atherothrombosis. We will finish by reviewing some antioxidant systems and compounds as therapeutic strategies to prevent pathological vascular remodeling.

Proteomics and metabolomics in biomarker discovery for cardiovascular diseases: progress and potential.

INTRODUCTION: The process of discovering novel biomarkers and potential therapeutic targets may be shortened using proteomic and metabolomic approaches. AREAS COVERED: Several complementary strategies, each one presenting different advantages and limitations, may be used with these novel approaches. In vitro studies show how cells involved in cardiovascular disease react, although the phenotype of cultured cells differs to that occurring in vivo. Tissue analysis either in human specimens or animal models may show the proteins that are expressed in the pathological process, although the presence of structural proteins may be confounding. To identify circulating biomarkers, analyzing the secretome of cultured atherosclerotic tissue, analysis of blood cells and/or plasma may be more straightforward. However, in the latter approach, high-abundant proteins may mask small molecules that could be potential biomarkers. The study of sub-proteomes such as high-density lipoproteins may be useful to circumvent this limitation. Regarding metabolomics, most studies have been performed in small populations, and we need to perform studies in large populations in order to discover robust biomarkers. Expert commentary: It is necessary to involve the clinicians in these areas to improve the design of clinical studies, including larger populations, in order to obtain consistent novel biomarkers.

Paraoxonase-1 overexpression prevents experimental abdominal aortic aneurysm progression.

Abdominal aortic aneurysm (AAA) is a permanent dilation of the aorta due to excessive proteolytic, oxidative and inflammatory injury of the aortic wall. We aimed to identify novel mediators involved in AAA pathophysiology, which could lead to novel therapeutic approaches. For that purpose, plasma from four AAA patients and four controls were analysed by a label-free proteomic approach. Among identified proteins, paraoxonase-1 (PON1) was decreased in plasma of AAA patients compared with controls, which was further validated in a bigger cohort of samples by ELISA. The phenylesterase enzymatic activity of PON1 was also decreased in serum of AAA patients compared with controls. To address the potential role of PON1 as a mediator of AAA, experimental AAA was induced by aortic elastase perfusion in wild-type (WT) mice and human transgenic PON1 (HuTgPON1) mice. Similar to humans, PON1 activity was also decreased in serum of elastase-induced AAA mice compared with healthy mice. Interestingly, overexpression of PON1 was accompanied by smaller aortic dilation and higher elastin and vascular smooth muscle cell (VSMC) content in the AAA of HuTgPON1 compared with WT mice. Moreover, HuTgPON1 mice display decreased oxidative stress and apoptosis, as well as macrophage infiltration and monocyte chemoattractant protein-1 (MCP1) expression, in elastase-induced AAA. In conclusion, decreased circulating PON1 activity is associated with human and experimental AAA. PON1 overexpression in mice protects against AAA progression by reducing oxidative stress, apoptosis and inflammation, suggesting that strategies aimed at increasing PON1 activity could prevent AAA.

The Prognostic Value of High-Sensitive Troponin I in Stable Coronary Artery Disease Depends on Age and Other Clinical Variables.

OBJECTIVES: To study the prognostic value of high-sensitive troponin (hs-cTn) I in stable coronary artery disease. METHODS: In total, we studied 705 patients. Secondary outcomes were the incidence of: (1) acute ischemic events and (2) heart failure or death. The primary outcome was the composite of them. RESULTS: Patients with hs-cTnI >0 ng/ml (62.1%) were older, had a lower estimated glomerular filtration rate, more frequent a history of hypertension, atrial fibrillation, ejection fraction <40%, and therapy with angiotensin-converting enzyme inhibitors, diuretics and acenocumarol. The follow-up period was 2.2 ± 0.99 years. Fifty-three patients suffered an acute ischemic event, 33 died or suffered heart failure and 78 developed the primary outcome. By univariate Cox's regression analysis, hs-cTnI >0 was associated with a higher risk of developing the primary outcome [relative risk = 2.360 (1.359-4.099); p = 0.001] and heart failure or death [relative risk = 5.932 (1.806-19.482); p < 0.001], but not with acute ischemic events. Statistical significance was lost after controlling for age. By logistic regression analysis, age [relative risk = 1.026 (1.009-1.044); p = 0.003], ejection fraction <40% [relative risk = 4.099 (2.043-8.224); p < 0.001], use of anticoagulants [relative risk = 2.785 (1.049-7.395); p = 0.040] and therapy with angiotensin-converting enzyme inhibitors [relative risk = 1.471 (1.064-2.034); p = 0.020], and estimated glomerular filtration rate [relative risk = 0.988 (0.977-0.999); p = 0.027] were associated with hs-cTnI >0. CONCLUSIONS: In stable coronary disease, hs-cTnI is associated with the incidence of heart failure or death, but this relationship depends on other variables.

Genetic deletion or TWEAK blocking antibody administration reduce atherosclerosis and enhance plaque stability in mice.

Clinical complications associated with atherosclerotic plaques arise from luminal obstruction due to plaque growth or destabilization leading to rupture. Tumour necrosis factor ligand superfamily member 12 (TNFSF12) also known as TNF-related weak inducer of apoptosis (TWEAK) is a proinflammatory cytokine that participates in atherosclerotic plaque development, but its role in plaque stability remains unclear. Using two different approaches, genetic deletion of TNFSF12 and treatment with a TWEAK blocking mAb in atherosclerosis-prone mice, we have analysed the effect of TWEAK inhibition on atherosclerotic plaques progression and stability. Mice lacking both TNFSF12 and Apolipoprotein E (TNFSF12(-/-) ApoE(-/-) ) exhibited a diminished atherosclerotic burden and lesion size in their aorta. Advanced atherosclerotic plaques of TNFSF12(-/-) ApoE(-/-) or anti-TWEAK treated mice exhibited an increase collagen/lipid and vascular smooth muscle cell/macrophage ratios compared with TNFSF12(+/+) ApoE(-/-) control mice, reflecting a more stable plaque phenotype. These changes are related with two different mechanisms, reduction of the inflammatory response (chemokines expression and secretion and nuclear factor kappa B activation) and decrease of metalloproteinase activity in atherosclerotic plaques of TNFSF12(-/-) ApoE(-/-) . A similar phenotype was observed with anti-TWEAK mAb treatment in TNFSF12(+/+) ApoE(-/-) mice. Brachiocephalic arteries were also examined since they exhibit additional features akin to human atherosclerotic plaques associated with instability and rupture. Features of greater plaque stability including augmented collagen/lipid ratio, reduced macrophage content, and less presence of lateral xanthomas, buried caps, medial erosion, intraplaque haemorrhage and calcium content were present in TNFSF12(-/-) ApoE(-/-) or anti-TWEAK treatment in TNFSF12(+/+) ApoE(-/-) mice. Overall, our data indicate that anti-TWEAK treatment has the capacity to diminish proinflamatory response associated with atherosclerotic plaque progression and to alter plaque morphology towards a stable phenotype.

HMGB1 expression and secretion are increased via TWEAK-Fn14 interaction in atherosclerotic plaques and cultured monocytes.

OBJECTIVE: High-mobility group box 1 (HMGB1), a DNA-binding cytokine expressed mainly by macrophages, contributes to lesion progression and chronic inflammation within atherosclerotic plaque. It has been suggested that different cytokines could regulate HMGB1 expression in monocytes. We have analyzed the effect of tumor necrosis factor-like weak inducer of apoptosis (TWEAK) on HMGB1 expression both in vivo and in vitro. METHODS AND RESULTS: Expression of TWEAK and its receptor fibroblast growth factor-inducible 14 (Fn14) was positively correlated with HMGB1 in human carotid atherosclerotic plaques. TWEAK increased HMGB1 mRNA expression and protein secretion in human acute monocytic leukemia cell line cultured monocytes. TWEAK-mediated HMGB1 increase was only observed in M1 macrophages but not in M2 ones. These effects were reversed using blocking anti-Fn14 antibody or nuclear factor-kappa B and phosphotidylinositol-3 kinase inhibitors. TWEAK also increased monocyte chemoattractant protein-1 secretion in human acute monocytic leukemia cell line cells, an effect blocked with an HMGB1 small interfering RNA. Systemic TWEAK injection in ApoE(-/-) mice increased HMGB1 protein expression in the aortic root and mRNA expression in total aorta of ApoE(-/-) mice. Conversely, TWEAK-blocking antibodies diminished HMGB1 protein and mRNA expression compared with IgG-treated mice. CONCLUSIONS: Our results indicate that TWEAK can regulate expression and secretion of HMGB1 in monocytes/macrophages, participating in the inflammatory response associated with atherosclerotic plaque development.

Proteomic analysis of intraluminal thrombus highlights complement activation in human abdominal aortic aneurysms.

OBJECTIVE: To identify proteins related to intraluminal thrombus biological activities that could help to find novel pathological mechanisms and therapeutic targets for human abdominal aortic aneurysm (AAA). APPROACH AND RESULTS: Tissue-conditioned media from patients with AAA were analyzed by a mass spectrometry-based strategy using liquid chromatography coupled to tandem mass spectrometry. Global pathway analysis by Ingenuity software highlighted the presence of several circulating proteins, among them were proteins from the complement system. Complement C3 concentration and activation were assessed in plasma from AAA patients (small AAA, AAA diameter=3-5 cm and large AAA, AAA diameter >5 cm), showing decreased C3 levels and activation in large AAA patients. No association of a combination of single-nucleotide polymorphisms in complement genes between large and small AAA patients was observed. Intense extracellular C3 inmunostaining, along with C9, was observed in AAA thrombus. Analysis of C3 in AAA tissue homogenates and tissue-conditioned media showed increased levels of C3 in AAA thrombus, as well as proteolytic fragments (C3a/C3c/C3dg), suggesting its local deposition and activation. Finally, the functional role of local complement activation in polymorphonuclear (PMN) cell activation was tested, showing that C3 blockade by anti-C3 antibody was able to decrease thrombus-induced neutrophil chemotaxis and reactive oxygen species production. CONCLUSIONS: A decrease of systemic C3 concentration and activity in the later stages of AAA associated with local complement retention, consumption, and proteolysis in the thrombus could induce PMN chemotaxis and activation, playing a detrimental role in AAA progression.

Assessment of biomarkers and predictive model for short-term prospective abdominal aortic aneurysm growth-A pilot study.

BACKGROUND: Abdominal aortic aneurysms (AAAs) are currently followed with serial ultrasound or computed tomography scanning diameter measurements, but evidence shows that AAA expansion is mostly discontinuous and quite unpredictable in any given patient. A reliable predictive model of AAA growth and/or rupture risk could help individualize treatment, follow-up protocols, and cost-effectiveness. Our objective is to set a predictive model of short-term prospective AAA growth, after clinical, serologic, and anatomic data. METHODS: A prospective pilot cohort was designed. We recruited 96 consecutive, asymptomatic, infrarenal, atherosclerotic AAA patients. We registered clinical data (age, gender, cardiovascular risk factors, comorbidity, and statin intake), baseline aortic diameter, prospective 1-year AAA growth, and the concentration of metalloprotease-2, metalloprotease-9, cystatin C, α1-antitrypsin, myeloperoxidase, monocyte chemoattractant protein-1, homocysteine, D-dimer, plasmin-antiplasmin complex (PAP), and C-reactive protein in peripheral blood at the time of baseline assessment. With all these data, we elaborated predictive models for 1-year AAA growth assessed both as a continuous variable (mm/year) and a dichotomic one (defined as stability, if AAA growth rate was ≤2 mm/year, versus expansion, if AAA growth rate was >2 mm/year), using simple and multiple linear and logistic regression. RESULTS: The multivariate model confirmed the independent impact of D-dimer levels and chronic renal failure (CRF) on increasing AAA growth rates. Every increase by 1 ng/mL in the plasma concentration of D-dimer was related to a mean 1-year increase of 0.0062 mm in the AAA growth. Likewise, CRF increased the 1-year prospective AAA growth by a mean of 2.95 mm. When we assessed AAA growth as a dichotomic variable, the increase in the peripheral concentrations of PAP slightly increased the risk of AAA expansion (odds ratio [OR]: 1.01; 95% confidence interval [CI]: 1.00-1.02), but the presence of CRF increased the risk dramatically (OR: 14,523.62; 95% CI: 0-7.39E+40). CONCLUSIONS: Plasma D-dimer and PAP levels seem promising biomarkers of short-term AAA activity. CRF is an important independent prognostic factor of AAA expansion. The dichotomic classification of AAA growth, as stability versus progression, can be useful in the development of management models and their clinical application.

In vitro 3D co-culture model of human endothelial and smooth muscle cells to study pathological vascular remodeling. / Modelo de cocultivo 3D in vitro de células endoteliales y vasculares de músculo liso humanas para el estudio del remodelado vascular patológico.

Pathological vascular remodeling of the vessel wall refers to the structural and functional changes of the vessel wall that occur in response to injury that eventually leads to cardiovascular disease. The vessel wall is composed of two main types of cells, endothelial cells and vascular smooth muscle cells, whose communication is crucial in both the development of the vasculature and the homeostasis of mature vessels. Changes in the dialogue between endothelial cells and vascular smooth muscle cells are associated with various pathological states that triggers remodeling of the vascular wall. For many years, considerable efforts have been made to develop effective diagnoses and treatments for these pathologies by studying their mechanisms in both in vitro and in vivo models. Compared to animal models, in vitro models can provide great opportunities to obtain data in a more homogeneous, economical and massive way, providing an overview of the signaling pathways responsible for these pathologies. The implementation of three-dimensional in vitro co-culture models for the study of other pathologies has been postulated as a potentially applicable methodology, which determines the importance of its application in studies of cardiovascular diseases. In this article we present a method for culturing human endothelial cells and vascular smooth muscle cells, grown under non-adherent conditions, that generate three-dimensional spheroidal structures with greater physiological equivalence to in vivo conditions. This in vitro modeling could be used as a study tool to identify cellular and molecular mechanisms involved in the pathological processes underlying vascular remodeling.

Soluble TWEAK plasma levels increase after renal transplantation and associate with the improvement of endothelial function.

BACKGROUND: Soluble TWEAK (sTWEAK) and asymmetric dimethyl arginine (ADMA) concentrations have been associated with endothelial function in patients with chronic kidney disease (CKD). We tested the hypothesis that the improvement in endothelial function observed after renal transplantation is directly linked to the normalization of both sTWEAK and ADMA. MATERIALS AND METHODS: One hundred and seventy-five kidney transplant recipients (71% men; 31·6 ± 9·4 years) were studied immediately before and on the 180th day post-transplantation. At each visit, blood samples were taken to assess circulating levels of sTWEAK and ADMA. Brachial artery endothelium-dependent vasodilatation (FMD) assessments were also performed. RESULTS: Renal transplantation was followed by an improvement in FMD. This improvement was paralleled by an increase in sTWEAK and a reduction in ADMA after transplantation (P < 0·001 for all). Cross-sectionally, both molecules associated with FMD before as well as after transplantation (P < 0·001 for all). Longitudinally, the changes observed in sTWEAK (ß = 0·26, P < 0·001) and ADMA (ß = -0·44, P < 0·001) levels were independently associated with the improvement of FMD (r(2)  = 0·30). CONCLUSIONS: Renal transplantation is followed by an improvement of FMD that is independently associated with the normalization of both sTWEAK and ADMA concentrations. We identify two surrogate biomarkers of endothelial function with potential as therapeutic targets.

Protection of diabetes in aortic abdominal aneurysm: Are antidiabetics the real effectors?

Aortic aneurysms, including abdominal aortic aneurysms (AAAs), is the second most prevalent aortic disease and represents an important cause of death worldwide. AAA is a permanent dilation of the aorta on its infrarenal portion, pathologically associated with oxidative stress, proteolysis, vascular smooth muscle cell loss, immune-inflammation, and extracellular matrix remodeling and degradation. Most epidemiological studies have shown a potential protective role of diabetes mellitus (DM) on the prevalence and incidence of AAA. The effect of DM on AAA might be explained mainly by two factors: hyperglycemia [or other DM-related factors such as insulin resistance (IR)] and/or by the effect of prescribed DM drugs, which may have a direct or indirect effect on the formation and progression of AAAs. However, recent studies further support that the protective role of DM in AAA may be attributable to antidiabetic therapies (i.e.: metformin or SGLT-2 inhibitors). This review summarizes current literature on the relationship between DM and the incidence, progression, and rupture of AAAs, and discusses the potential cellular and molecular pathways that may be involved in its vascular effects. Besides, we provide a summary of current antidiabetic therapies which use could be beneficial for AAA.

The presence of activating IgG Fc receptors in macrophages aggravates the development of experimental abdominal aortic aneurysm. / La presencia de receptores Fc de IgG activadores en macrófagos agrava el desarrollo de aneurisma aórtico abdominal experimental.

INTRODUCTION: Abdominal aortic aneurysm (AAA) is a multifactorial, degenerative disease characterized by progressive aortic dilation and chronic activation of inflammation, proteolytic activity, and oxidative stress in the aortic wall. The immune response triggered by antibodies against antigens present in the vascular wall participates in the formation and progression of AAA through mechanisms not completely understood. This work analyses the function of specific IgG receptors (FcγR), especially those expressed by monocytes/macrophages, in the development of experimental AAA. METHODS: In the elastase-induced AAA model, the abdominal aortas from wildtype and FcγR deficient mice with/without macrophage adoptive transfer were analysed by histology and quantitative PCR. In vitro, mouse macrophages were transfected with RNA interference of FcγRIV/CD16.2 or treated with Syk kinase inhibitor before stimulation with IgG immune complexes. RESULTS: Macrophage adoptive transfer in FcγR deficient mice increased the susceptibility to AAA development. Mice receiving macrophages with functional FcγR exhibited higher aortic diameter increase, higher content of macrophages and B lymphocytes, and upregulated expression of chemokine CCL2, cytokines (TNF-α and IL-17), metalloproteinase MMP2, prooxidant enzyme NADPH oxidase-2, and the isoforms FcγRIII/CD16 and FcγRIV/CD16.2. In vitro, both FcγRIV/CD16.2 gene silencing and Syk inhibition reduced cytokines and reactive oxygen species production induced by immune complexes in macrophages. CONCLUSIONS: Activation of macrophage FcγR contributes to AAA development by inducing mediators of inflammation, proteolysis, and oxidative stress. Modulation of FcγR or effector molecules may represent a potential target for AAA treatment.