Regulation of Nox enzymes expression in vascular pathophysiology: Focusing on transcription factors and epigenetic mechanisms.

NADPH oxidases (Nox) represent a family of hetero-oligomeric enzymes whose exclusive biological function is the generation of reactive oxygen species (ROS). Nox-derived ROS are essential modulators of signal transduction pathways that control key physiological activities such as cell growth, proliferation, migration, differentiation, and apoptosis, immune responses, and biochemical pathways. Enhanced formation of Nox-derived ROS, which is generally associated with the up-regulation of different Nox subtypes, has been established in various pathologies, namely cardiovascular diseases, diabetes, obesity, cancer, and neurodegeneration.

Metformin reduces the endotoxin-induced down-regulation of apolipoprotein E gene expression in macrophages.

The atheroprotective role of macrophage-derived apolipoprotein E (apoE) is well known. Our previous reports demonstrated that inflammatory stress down-regulates apoE expression in macrophages, aggravating atherogenesis. Metformin, extensively used as an anti-diabetic drug, has also anti-inflammatory properties, and thus confers vascular protection.

Human monocytes and macrophages express NADPH oxidase 5; a potential source of reactive oxygen species in atherosclerosis.

Monocytes (Mon) and Mon-derived macrophages (Mac) orchestrate important oxidative and inflammatory reactions in atherosclerosis by secreting reactive oxygen species (ROS) due, in large part, to the upregulated NADPH oxidases (Nox). The Nox enzymes have been extensively investigated in human Mon and Mac. However, the expression and functional significance of the Nox5 subtypes is not known.

High-glucose-increased expression and activation of NADPH oxidase in human vascular smooth muscle cells is mediated by 4-hydroxynonenal-activated PPARα and PPARβ/δ.

High glucose induces vascular smooth muscle cell (SMC) dysfunction by generating oxidative stress attributable, in part, to the up-regulated NADPH oxidases (Nox). We have attempted to elucidate the high-glucose-generated molecular signals that mediate this effect and hypothesize that products of high-glucose-induced lipid peroxidation regulate Nox by activating peroxisome proliferator-activated receptors (PPARs). Human aortic SMCs were exposed to glucose (5.

Antimicrobial nanospheres thin coatings prepared by advanced pulsed laser technique.

We report on the fabrication of thin coatings based on polylactic acid-chitosan-magnetite-eugenol (PLA-CS-Fe3O4@EUG) nanospheres by matrix assisted pulsed laser evaporation (MAPLE). Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) investigation proved that the homogenous Fe3O4@EUG nanoparticles have an average diameter of about 7 nm, while the PLA-CS-Fe3O4@EUG nanospheres diameter sizes range between 20 and 80 nm. These MAPLE-deposited coatings acted as bioactive nanosystems and exhibited a great antimicrobial effect by impairing the adherence and biofilm formation of Staphylococcus aureus (S.

MAPLE fabricated Fe3O4@Cinnamomum verum antimicrobial surfaces for improved gastrostomy tubes.

Cinnamomum verum-functionalized Fe3O4 nanoparticles of 9.4 nm in size were laser transferred by matrix assisted pulsed laser evaporation (MAPLE) technique onto gastrostomy tubes (G-tubes) for antibacterial activity evaluation toward Gram positive and Gram negative microbial colonization. X-ray diffraction analysis of the nanoparticle powder showed a polycrystalline magnetite structure, whereas infrared mapping confirmed the integrity of C.

Subendothelial resistin enhances monocyte transmigration in a co-culture of human endothelial and smooth muscle cells by mechanisms involving fractalkine, MCP-1 and activation of TLR4 and Gi/o proteins signaling.

The cytokine resistin and the chemokine fractalkine (FKN) were found at increased levels in human atherosclerotic plaque, in the subendothelium, but their role in this location still needs to be characterized. Recently, high local resistin in the arterial vessel wall was shown to contribute to an enhanced accumulation of macrophages by mechanisms that need to be clarified. Our recent data showed that resistin activated smooth muscle cells (SMC) by up-regulating FKN and MCP-1 expression and monocyte chemotaxis by activating toll-like receptor 4 (TLR4) and Gi/o proteins.

Anionic polymers and 10 nm Fe₃O₄@UA wound dressings support human foetal stem cells normal development and exhibit great antimicrobial properties.

The aims of this study were the development, characterization and bioevaluation of a novel biocompatible, resorbable and bio-active wound dressing prototype, based on anionic polymers (sodium alginate--AlgNa, carboximethylcellulose--CMC) and magnetic nanoparticles loaded with usnic acid (Fe₃O₄@UA). The antimicrobial activity was tested against Staphylococcus aureus grown in biofilms. The biocompatibility testing model included an endothelial cell line from human umbilical vein and human foetal progenitor cells derived from the amniotic fluid, that express a wide spectrum of surface molecules involved in different vascular functions and inflammatory response, and may be used as skin regenerative support.

The involvement of the monocytes/macrophages in chronic inflammation associated with atherosclerosis.

Atherosclerosis is a progressive chronic disease of large and medium arteries, characterized by the formation of atherosclerotic plaques. Monocytes and macrophages are key factors in lesion development, participating to the processes that mediate the progression of the atherosclerotic plaque (lipid accumulation, secretion of pro-inflammatory and cytotoxic factors, extracellular matrix remodeling). The recruitment of the monocytes in the vascular wall represents a hallmark in the pathology of the atherosclerotic lesion.

Histone deacetylase (HDAC) inhibitors down-regulate endothelial lineage commitment of umbilical cord blood derived endothelial progenitor cells.

To test the involvement of histone deacetylases (HDACs) activity in endothelial lineage progression, we investigated the effects of HDAC inhibitors on endothelial progenitors cells (EPCs) derived from umbilical cord blood (UCB). Adherent EPCs, that expressed the endothelial marker proteins (PCAM-1, CD105, CD133, and VEGFR(2)) revealed by flow cytometry were treated with three HDAC inhibitors: Butyrate (BuA), Trichostatin A (TSA), and Valproic acid (VPA). RT-PCR assay showed that HDAC inhibitors down-regulated the expression of endothelial genes such as VE-cadherin, CD133, CXCR4 and Tie-2.

Cross talk between smooth muscle cells and monocytes/activated monocytes via CX3CL1/CX3CR1 axis augments expression of pro-atherogenic molecules.

Objective: In atherosclerotic lesions, fractalkine (CX3CL1) and its receptor (CX3CR1) expressed by smooth muscle cells (SMC) and monocytes/macrophages, mediate the heterotypic anchorage and chemotaxis of these cells. We questioned whether, during the close interaction of monocytes with SMC, the CX3CL1/CX3CR1 pair modulates the expression of pro-atherogenic molecules in these cells.

Methods And Results: SMC were co-cultured with monocytes or LPS-activated monocytes (18h) and then the cells were separated and individually investigated for the gene and protein expression of TNFα, IL-1β, IL-6, CX3CR1 and metalloproteinases (MMP-2, MMP-9).

Integration properties of Wharton's jelly-derived novel mesenchymal stem cells into ventricular slices of murine hearts.

Wharton's jelly (WJ) is a rich source of multiple-lineage differentiating cells, recently proposed for cell replacement therapy. However, their ability to integrate into the cardiac tissue has not been elucidated, yet. We employed in vitro cardiac transplantation models to investigate the capacity of a novel population of human WJ-derived mesenchymal stem cells (nMSCs) to integrate into both living and ischemic cardiac tissue.

Curcumin and a Morus alba extract reduce pro-inflammatory effects of resistin in human endothelial cells.

Resistin is a cytokine which plays an important role in cardiovascular disease by influencing systemic inflammation and endothelial activation. In human endothelial cells (HEC) it increases the expression of P-selectin and fractalkine, and enhances monocyte adhesion by antioxidant mechanisms. This study investigated whether the natural antioxidants curcumin (CC) and an extract of Morus alba leaves (MA) have protective effects in resistin-activated HEC.

Platelet activation in hypertension associated with hypercholesterolemia: effects of irbesartan.

Aim: The aim of this study was to determine the effect of simultaneous hypertension and hypercholesterolemia on platelet activation, nitric oxide (NO) production and oxidative stress, and to evaluate the role of irbesartan, an angiotensin II type 1 receptor antagonist.

Methods: Golden Syrian hamsters were divided into three groups: controls, C (fed a standard diet); hypertensive-hypercholesterolemic, HH (fed a diet enriched in 3% cholesterol, 15% butter and 8% NaCl, for 4 months); and hypertensive-hypercholesterolemic treated with irbesartan, HHI (fed as HH group, plus irbesartan 10 mg kg(-1) per day, for 4 months).

Results: Compared with the C group, platelets isolated from the HH group showed: morphological modifications; increased integrin β3 exposure and protein expression of P-selectin, FAK, PI3K, Akt and Src; reduced eNOS protein expression and NO production; higher generation of ROS, mostly produced by NADPH-oxidase, cyclooxygenase-1 (COX-1) and 12-lipoxygenase; and enhanced NAD(P)H oxidase activity and protein expression of gp91phox and p22phox subunits, 12-lipoxygenase, COX-1, cPLA(2) and PKC.

Transcriptional regulation of NADPH oxidase isoforms, Nox1 and Nox4, by nuclear factor-kappaB in human aortic smooth muscle cells.

Inflammation-induced changes in the activity and expression of NADPH oxidases (Nox) play a key role in atherogenesis. The molecular mechanisms of Nox regulation are scantily elucidated. Since nuclear factor-kappaB (NF-kappaB) controls the expression of many genes associated to inflammation-related diseases, in this study we have investigated the role of NF-kappaB signaling in the regulation of Nox1 and Nox4 transcription in human aortic smooth muscle cells (SMCs).

Similar effects of resistin and high glucose on P-selectin and fractalkine expression and monocyte adhesion in human endothelial cells.

Resistin and high glucose (HG) are concomitantly present at elevated concentration in diabetic's plasma; both are pro-inflammatory agents acting on vascular cells by mechanisms that are not fully understood. We questioned whether resistin and HG affect the expression of major adhesion molecules, P-selectin and fractalkine in human endothelial cells (HEC). The results showed that in HEC (i) resistin increased P-selectin expression; (ii) HG up-regulated Fk expression; (iii) P-selectin and fractalkine were functional increasing monocyte adhesion to activated cells.

Leptin G-2548A and leptin receptor Q223R gene polymorphisms are not associated with obesity in Romanian subjects.

We aimed to investigate whether polymorphisms LEP G-2548A and LEPR Q223R in the human leptin (LEP), and leptin receptor (LEPR) genes are associated with obesity and metabolic traits in a sample of Romanian population. Two hundred and two subjects divided in obese (body mass index, BMI30 kg/m(2)), and non-obese were included in this study. The polymorphisms were genotyped using polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) analysis.

Effect of irreversibly glycated LDL in human vascular smooth muscle cells: lipid loading, oxidative and inflammatory stress.

The major complication of diabetes is accelerated atherosclerosis, the progression of which entails complex interactions between the modified low-density lipoproteins (LDL) and the cells of the arterial wall. Advanced glycation end product-modified-LDL (AGE-LDL) that occurs at high rate in diabetes contributes to diabetic atherosclerosis, but the underlying mechanisms are not fully understood. The aim of this study was to assess the direct effect of AGE-LDL on human vascular smooth muscle cells (hSMC) dysfunction.

Chronic venous insufficiency is associated with elevated level of circulating microparticles.

Background: Chronic venous insufficiency (CVI) results when the veins in the legs no longer pump blood back to the heart effectively. Microparticles (MPs) are small membrane vesicles released by several circulating and vascular cells upon activation or apoptosis.

Objectives: The purpose of this study was to assess the subpopulations of circulating endothelial (EMPs) and platelet microparticles (PMPs) in CVI, and to disclose their contribution in mediating dysfunction of human peripheral venules.

Resistin up-regulates fractalkine expression in human endothelial cells: lack of additive effect with TNF-alpha.

Resistin is a cytokine and fractalkine (Fk) a cell adhesion molecule and chemokine that contribute to human vascular inflammation by mechanisms not clearly defined. We questioned whether resistin induces Fk expression in human endothelial cells (HEC), compared the effect with that of the pro-inflammatory cytokine, TNF-alpha, and evaluated the consequences of co-stimulating HEC with both activators on Fk induction and on the signalling molecules involved. We found that resistin up-regulated Fk expression at comparable level to that of TNF-alpha by a mechanism involving P38 and JNK MAPK and NF-kappaB.

Effect of depletion of monocytes/macrophages on early aortic valve lesion in experimental hyperlipidemia.

Monocytes/macrophages are key players throughout atheroma development. The aim of this study was to determine the role of macrophages in lesion formation in heart valves in hyperlipidemia. We examined whether systemic depletion of monocytes/macrophages had a beneficial or adverse effect on the development of lesions in hyperlipemic hamsters injected twice weekly (for 2 months) with clodronate-encapsulated liposomes (H+Lclod), a treatment that selectively induces significant monocyte apoptosis.

Endothelial transcytosis in health and disease.

The visionaries predicted the existence of transcytosis in endothelial cells; the cell biologists deciphered its mechanisms and (in part) the molecules involved in the process; the cell pathologists unravelled the presence of defective transcytosis in some diseases. The optimistic perspective is that transcytosis, in general, and receptor-mediated transcytosis, in particular, will be greatly exploited in order to target drugs and genes to exclusive sites in and on endothelial cells (EC) or underlying cells. The current recognition that plasmalemmal vesicles (caveolae) are the vehicles involved in EC transcytosis has moved through various phases from initial considerations of caveolae as unmovable sessile non-functional plasmalemma invaginations to the present identification of a multitude of molecules and a crowd of functions associated with these ubiquitous structures of endothelial and epithelial cells.

Vascular endothelium in atherosclerosis.

Their strategic location between blood and tissue and their constitutive properties allow endothelial cells (EC) to monitor the transport of plasma molecules, by employing bidirectional receptor-mediated and receptor-independent transcytosis and endocytosis, and to regulate vascular tone, cellular cholesterol and lipid homeostasis. These cells are also involved in signal transduction, immunity, inflammation and haemostasis. Cardiovascular risk factors, such as hyperlipaemia/dyslipidaemia trigger the molecular machinery of EC to respond to insults by modulation of their constitutive functions followed by dysfunction and ultimately by injury and apoptosis.

Apolipoprotein E polymorphism--a risk factor for metabolic syndrome.

Background: Metabolic syndrome is closely related to several disturbances in lipid and lipoprotein metabolism. The aim of this study was to determine the association between apolipoprotein E (apoE) genotypes and the risk of metabolic syndrome and/or coronary heart disease complications.

Methods: The study included 279 subjects divided into three groups: 1) control subjects, 2) metabolic syndrome patients, and 3) obese patients with coronary heart disease.

Apolipoprotein A-V gene polymorphisms in subjects with metabolic syndrome.

Background: Genetic variation at the apolipoprotein A-V locus, recently discovered proximal to the APOA1/C3/A4 gene cluster, is associated with elevated triglyceride concentrations, a risk factor for atherosclerosis.

Methods: The goal of our study was to determine the association of two apolipoprotein A-V (APOA5) gene polymorphisms in a group of urban Romanian subjects with the prevalence of the metabolic syndrome. For this purpose, we assayed -1.