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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., (Copyright © 2024 The Author(s). Publicado por Elsevier España, S.L.U. All rights reserved.)

Introduction: Lysyl oxidase (LOX) participates in the assembly of collagen and elastin fibres. The impact of vascular LOX over-expression on extracellular matrix (ECM) structure and its contribution to oxidative stress has been analysed., Methods: Studies were conducted on mice over-expressing LOX (Tg), specifically in smooth muscle cells (VSMC). Gene expression was assessed by real-time PCR analysis. Sirius Red staining, H 2 O 2 production and NADPH oxidase activity were analysed in different vascular beds. The size and number of fenestra of the internal elastic lamina were determined by confocal microscopy., Results: LOX activity was up-regulated in VSMC of transgenic mice compared with cells from control animals. At the same time, transgenic cells deposited more organised elastin fibres and their supernatants induced a stronger collagen assembly in in vitro assays. Vascular collagen cross-linking was also higher in Tg mice, which showed a decrease in the size of fenestrae and an enhanced expression of Fibulin-5. Interestingly, higher H 2 O 2 production and NADPH oxidase activity was detected in the vascular wall from transgenic mice. The H 2 O 2 scavenger catalase attenuated the stronger deposition of mature elastin fibres induced by LOX transgenesis., Conclusions: LOX over-expression in VSMC was associated with a change in the structure of collagen and elastin fibres. LOX could constitute a novel source of oxidative stress that might participate in elastin changes and contribute to vascular remodelling., (Copyright © 2017 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.)

Introduction: Fibulin-5 (FBLN5) is an elastogenic protein critically involved in extracellular matrix (ECM) remodelling, a key process in abdominal aortic aneurysm (AAA). However, the possible contribution of FBLN5 to AAA development has not been addressed., Methods: Expression levels were determined by real-time PCR and Western blot in human abdominal aorta from patients with AAA or healthy donors, as well as in human aortic vascular smooth muscle cells (VSMC). Lentiviral transduction, transient transfections, and chromatin immunoprecipitation (ChIP) assays were also performed., Results: The expression of FBLN5 in human AAA was significantly lower than in healthy donors. FBLN5 mRNA and protein levels and their secretion to the extracellular environment were down-regulated in VSMC exposed to inflammatory stimuli. Interestingly, FBLN5 transcriptional activity was inhibited by TNFα and lipopolysaccharide (LPS), and depends on a SOX response element. In fact, SOX9 expression was reduced in VMSC induced by inflammatory mediators and in human AAA, and correlated with that of FBLN5. Furthermore, SOX9 over-expression limited the reduction of FBLN5 expression induced by cytokines in VSMC. Finally, it was observed that SOX9 interacts with FBLN5 promoter, and that this binding was reduced upon TNFα exposure., Conclusions: FBLN5 downregulation in human AAA could contribute to extracellular matrix remodelling induced by the inflammatory component of the disease., (Copyright © 2016 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.)

Introduction: Previous studies have shown that the loss of NOR-1 function modulates the activation of vascular smooth muscle cells (VSMC). In this study we use a mouse that over-expresses human NOR-1 in VSMC to analyze the effect of a gain of NOR-1 function on the activation of VSMC and in the hyperplasia of the intima induced by hemodynamic stress., Methods: To generate the transgenic animal the human NOR-1 cDNA was placed under the control of the SM22α promoter. The expression of NOR-1 was analyzed by real time PCR, Western blot, immunohistochemistry and immunocitochemistry, and NOR-1 functionality was evaluated by luciferase activity assays. The incorporation of tritiated thymidine was determined as a cell proliferation index. The left carotid artery was ligated, and cross-sections were subjected to morphometric and immunostaining analysis., Results: The transgenic mouse exhibited significant levels of human NOR-1 in aorta and carotid arteries. In aortic VSMC from transgenic mice an increase in the transcriptional activity of ciclin D2 was detected, as well as higher proliferative rates and increased levels of the marker Myh10. In these animals, carotid artery ligation induced a greater neointimal formation and a higher stenotic grade than in wild-type animals, in accordance with the labelling detected for Myh10 and phosphorylated Histone H3., Conclusions: These results reinforce the role of NOR-1 in VSMC proliferation and in vascular remodelling, and allow us to propose this model as a useful tool to study the involvement of NOR-1 in vascular function and in vascular diseases such as atherosclerosis and restenosis., (Copyright © 2013 Elsevier España, S.L. y SEA. All rights reserved.)

HMG-CoA-Reductase inhibitors, also known as statins, are currently the most powerful cholesterol-lowering drugs available on the market. Clinical trials and experimental evidence suggest that statins have heavy anti-atherosclerotic effects. These are in part consequence of lipid lowering but also result from pleiotropic actions of the drugs. These so-called pleiotropic properties affect various aspects of cell function, inflammation, coagulation, and vasomotor activity. These effects are mediated either indirectly through LDL-c reduction or via a direct effect on cellular functions. Although many of the pleiotropic properties of statins may be a class effect, some may be unique to certain agents and account for differences in their pharmacological activity. So, although statins typically have similar effects on LDL-c levels, differences in chemical structure and pharmacokinetic profile can lead to variations in pleiotropic effects. In this paper we analize the in vitro effects of different statins over different cell lines from cells implicated in atherosclerotic process: endothelial cells, fibroblasts, and vascular muscular cells. In relation with our results we can proof that the effects of different dosis of different statins provides singular effects over growth curves of different cellular lines, a despite of a class-dependent effects. So, pleiotropic effects and its reversibility with mevalonate are different according with the molecule and the dosis., (Copyright © 2013 Elsevier España, S.L. y SEA. All rights reserved.)

Atherosclerosis is the principal cause of myocardial infarction, stroke, and peripheral vascular disease, accounting for nearly half of all mortality in developed countries. The excessive growth of vascular smooth muscle cells is an important component in the development of atherosclerotic lesion. The direct effect of calcitriol and vitamin D analogs on the VSMCs proliferation is not clear. In this study we have analysed if calcitriol, Paricalcitol (19-nor-1,25-dihydroxy-vitamin D2) and EB1089 (experimental analog used as anticancerous) modify proliferation and the expression of vitamin D receptor (VDR) gene that is regulated at the transcriptional level by itself in the VSMCs. VSMCs proliferation was analysed by BrdU incorporation and VDR gene expression using RT-PCR. VSMCs proliferation was stimulated when calcitriol was added to the culture. VSMCs proliferation was significantly lower with analogs at the same dose. With regard to the functional study, the expression of VDR gene was upregulated by calcitriol at a concentration of 100 nM. There were no changes in this expression with the analogs. In conclusion, calcitriol, do not modify VSMCs proliferation. Therefore, Paricalcitol could have a minor proliferating effect on the wall of vessels that vitamin D.

Introduction: Hypercholesterolemia is associated with increased platelet reactivity and changes in megakaryopoiesis, which might influence the synthesis of growth factors in the megakaryocyte., Material and Methods: 20 miniature pigs were randomly assigned to received 18 weeks of either regular pig chow feed (control group, n = 10) or a high cholesterol diet (cholesterol group, n = 10). Platelet count, mean platelet volume, platelet distribution width and bleeding time were determined in both groups. Intraplatelet and serum mitogenic activity was quantified by Swiss 3T3 and vascular smooth muscle cells proliferation assays. Insulin-like growth factor I and platelet-derived growth factor (BB isoform) levels were quantified in platelet lysates and in serum in both groups., Results: Hypercholesterolemia was associated to a significant decrease in mean platelet volume and bleeding time, but it did not affect the proliferative effect of serum and platelet lysates nor its growth factor content., Conclusions: Taken together, our results suggest that although hypercholesterolemia affects platelet reactivity, its atherosclerosis-promoting effects cannot be explained by a direct effect on vascular smooth muscle cell proliferation or by changes in serum or intraplatelet growth factor content.