Unravelling molecular mechanisms in atherosclerosis using cellular models and omics technologies.

Despite the discovery and prevalent clinical use of potent lipid-lowering therapies, including statins and PCSK9 inhibitors, cardiovascular diseases (CVD) caused by atherosclerosis remain a large unmet clinical need, accounting for frequent deaths worldwide. The pathogenesis of atherosclerosis is a complex process underlying the presence of modifiable and non-modifiable risk factors affecting several cell types including endothelial cells (ECs), monocytes/macrophages, smooth muscle cells (SMCs) and T cells. Heterogeneous composition of the plaque and its morphology could lead to rupture or erosion causing thrombosis, even a sudden death.

Peroxisome Proliferator-Activated Receptor α in Lipoprotein Metabolism and Atherosclerotic Cardiovascular Disease.

Peroxisome proliferator-activated receptors (PPARs) are a group of ligand-binding transcription factors with pivotal action in regulating pleiotropic signaling pathways of energetic metabolism, immune responses and cell proliferation and differentiation. A significant body of evidence indicates that the PPARα receptor is an important modulator of plasma lipid and lipoprotein metabolism, with pluripotent effects influencing the lipid and apolipoprotein cargo of both atherogenic and antiatherogenic lipoproteins and their functionality. Clinical evidence supports an important role of PPARα agonists (fibric acid derivatives) in the treatment of hypertriglyceridemia and/or low high-density lipoprotein (HDL) cholesterol levels, although the effects of clinical trials are contradictory and point to a reduction in the risk of nonfatal and fatal myocardial infarction events.

Proteometabolomics of initial and recurrent glioblastoma highlights an increased immune cell signature with altered lipid metabolism.

Background: There is an urgent need to better understand the mechanisms associated with the development, progression, and onset of recurrence after initial surgery in glioblastoma (GBM). The use of integrative phenotype-focused -omics technologies such as proteomics and lipidomics provides an unbiased approach to explore the molecular evolution of the tumor and its associated environment.

Methods: We assembled a cohort of patient-matched initial (iGBM) and recurrent (rGBM) specimens of resected GBM.

Apolipoprotein A-II, a Player in Multiple Processes and Diseases.

Apolipoprotein A-II (apoA-II) is the second most abundant apolipoprotein in high-density lipoprotein (HDL) particles, playing an important role in lipid metabolism. Human and murine apoA-II proteins have dissimilar properties, partially because human apoA-II is dimeric whereas the murine homolog is a monomer, suggesting that the role of apoA-II may be quite different in humans and mice. As a component of HDL, apoA-II influences lipid metabolism, being directly or indirectly involved in vascular diseases.

Synthetic lipoproteins based on apolipoprotein E coupled to fullerenol have anti-atherosclerotic properties.

Background: Apolipoprotein E (apoE) is an anti-atherosclerotic protein associated with almost all plasma lipoproteins. Fullerenol (Full-OH) contains the fullerene hydrophobic cage and several hydroxyl groups that could be derivatized to covalently bind various molecules. Herein, we aimed to produce fullerenol-based nanoparticles carrying apoE3 (Full-apoE) and test their anti-atherosclerotic effects.

Treatment with Mesenchymal Stromal Cells Overexpressing Fas-Ligand Ameliorates Acute Graft-versus-Host Disease in Mice.

Allogeneic hematopoietic cell transplantation (allo-HCT) has the potential to cure malignant and non-malignant hematological disorders, but because of the serious side effects of this intervention its applications are limited to a restricted number of diseases. Graft-versus-host disease (GvHD) is the most frequent complication and the leading cause of mortality and morbidity following allo-HCT. It results from the attack of the transplanted T cells from the graft against the cells of the recipient.

An Efficient Method for Adenovirus Production.

Adenoviral transduction has the advantage of a strong and transient induction of the expression of the gene of interest into a broad variety of cell types and organs. However, recombinant adenoviral technology is laborious, time-consuming, and expensive. Here, we present an improved protocol using the pAdEasy system to obtain purified adenoviral particles that can induce a strong green fluorescent protein (GFP) expression in transduced cells.

K2 Transfection System Boosts the Adenoviral Transduction of Murine Mesenchymal Stromal Cells.

Adenoviral vectors are important vehicles for delivering therapeutic genes into mammalian cells. However, the yield of the adenoviral transduction of murine mesenchymal stromal cells (MSC) is low. Here, we aimed to improve the adenoviral transduction efficiency of bone marrow-derived MSC.

Enhanced Suppression of Immune Cells In Vitro by MSC Overexpressing FasL.

Mesenchymal stromal cells (MSC) display several mechanisms of action that may be harnessed for therapeutic purposes. One of their most attractive features is their immunomodulatory activity that has been extensively characterized both in vitro and in vivo. While this activity has proven to be very efficient, it is transient.

Adenovirus-Mediated Minigene Transfer Endows Transduced Cells with Killer Potential.

Fas ligand (First apoptosis signal ligand, FasL, also known as CD95L) is the common executioner of apoptosis within the tumor necrosis factor (TNF) superfamily. We aimed to induce functional FasL expression in transduced cells using an adenovirus vector, which has the advantage of strong and transient induction of the gene included in the adenoviral genome. Here, we report that the adenovirus carrying a truncated gene, named minigene, encoding the full-length FasL protein (Ad-gFasL) is more efficient than the adenovirus carrying FasL cDNA (Ad-cFasL) in the induction of FasL expression in transduced cells.

The Mechanism of Bisphenol A Atherogenicity Involves Apolipoprotein A-I Downregulation through NF-κB Activation.

Apolipoprotein A-I (apoA-I) is the major protein component of high-density lipoproteins (HDL), mediating many of its atheroprotective properties. Increasing data reveal the pro-atherogenic effects of bisphenol A (BPA), one of the most prevalent environmental chemicals. In this study, we investigated the mechanisms by which BPA exerts pro-atherogenic effects.

Apolipoprotein C1: Its Pleiotropic Effects in Lipid Metabolism and Beyond.

Apolipoprotein C1 (apoC1), the smallest of all apolipoproteins, participates in lipid transport and metabolism. In humans, gene is in linkage disequilibrium with gene on chromosome 19, a proximity that spurred its investigation. Apolipoprotein C1 associates with triglyceride-rich lipoproteins and HDL and exchanges between lipoprotein classes.

The Opposite Effect of c-Jun Transcription Factor on Apolipoprotein E Gene Regulation in Hepatocytes and Macrophages.

Apolipoprotein E (apoE) is mainly secreted by hepatocytes and incorporated into most plasma lipoproteins. Macrophages, which accumulate cholesterol and are critical for the development of the atherosclerotic plaque, are also an important, albeit smaller, apoE source. Distal regulatory elements control cell-specific activity of the apoE promoter: multienhancers (ME.

Apolipoprotein E - A Multifunctional Protein with Implications in Various Pathologies as a Result of Its Structural Features.

Apolipoprotein E (apoE), a 34 kDa glycoprotein, mediates hepatic and extrahepatic uptake of plasma lipoproteins and cholesterol efflux from lipid-laden macrophages. In humans, three structural different apoE isoforms occur, with subsequent functional changes and pathological consequences. Here, we review data supporting the involvement of apoE structural domains and isoforms in normal and altered lipid metabolism, cardiovascular and neurodegenerative diseases, as well as stress-related pathological states.

Preferential Association of Lissencephaly-1 Gene Expression with CD133+ Glioblastoma Cells.

Lissencephaly-1 (Lis1) protein is a dynein-binding protein involved in neural stem cell division, morphogenesis and motility. To determine whether Lis1 is a key factor in glioblastoma, we evaluated its expression and function in CD133+ glioblastoma cells. Global, Lis1 gene expression is similar in glioblastoma and normal samples.

Differential action of glucocorticoids on apolipoprotein E gene expression in macrophages and hepatocytes.

Apolipoprotein E (apoE) has anti-atherosclerotic properties, being involved in the transport and clearance of cholesterol-rich lipoproteins as well as in cholesterol efflux from cells. We hypothesized that glucocorticoids may exert anti-inflammatory properties by increasing the level of macrophage-derived apoE. Our data showed that glucocorticoids increased apoE expression in macrophages in vitro as well as in vivo.

High levels of homocysteine downregulate apolipoprotein E expression via nuclear factor kappa B.

Aim: To investigate the effect of high homocysteine (Hcy) levels on apolipoprotein E (apoE) expression and the signaling pathways involved in this gene regulation.

Methods: Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot were used to assess apoE expression in cells treated with various concentrations (50-500 μmol/L) of Hcy. Calcium phosphate-transient transfections were performed in HEK-293 and RAW 264.

Krüppel-like factor 4 synergizes with CREB to increase the activity of apolipoprotein E gene promoter in macrophages.

Krüppel-like factor 4 (KLF4) is a critical regulator of monocyte differentiation and macrophage polarization, and it also plays an important role in several vascular diseases, including atherosclerosis. Apolipoprotein E (apoE) is an essential anti-atherosclerotic glycoprotein involved in lipid metabolism, expressed by the liver, macrophages and other cell types. We hypothesized that KLF4 is involved in apoE gene regulation in macrophages.

Thyroid hormones upregulate apolipoprotein E gene expression in astrocytes.

Apolipoprotein E (apoE), a protein mainly involved in lipid metabolism, is associated with several neurodegenerative disorders including Alzheimer's disease. Despite numerous attempts to elucidate apoE gene regulation in the brain, the exact mechanism is still uncovered. The mechanism of apoE gene regulation in the brain involves the proximal promoter and multienhancers ME.

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.

Regulation of HDL genes: transcriptional, posttranscriptional, and posttranslational.

HDL regulation is exerted at multiple levels including regulation at the level of transcription initiation by transcription factors and signal transduction cascades; regulation at the posttranscriptional level by microRNAs and other noncoding RNAs which bind to the coding or noncoding regions of HDL genes regulating mRNA stability and translation; as well as regulation at the posttranslational level by protein modifications, intracellular trafficking, and degradation. The above mechanisms have drastic effects on several HDL-mediated processes including HDL biogenesis, remodeling, cholesterol efflux and uptake, as well as atheroprotective functions on the cells of the arterial wall. The emphasis is on mechanisms that operate in physiologically relevant tissues such as the liver (which accounts for 80% of the total HDL-C levels in the plasma), the macrophages, the adrenals, and the endothelium.

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.

STAT1 interacts with RXRα to upregulate ApoCII gene expression in macrophages.

Apolipoprotein CII (apoCII) is a specific activator of lipoprotein lipase and plays an important role in triglyceride metabolism. The aim of our work was to elucidate the regulatory mechanisms involved in apoCII gene modulation in macrophages. Using Chromosome Conformation Capture we demonstrated that multienhancer 2 (ME.

Macrophage-specific up-regulation of apolipoprotein E gene expression by STAT1 is achieved via long range genomic interactions.

In atherogenesis, macrophage-derived apolipoprotein E (apoE) has an athero-protective role by a mechanism that is not fully understood. We investigated the regulatory mechanisms involved in the modulation of apoE expression in macrophages. The experiments showed that the promoters of all genes of the apoE/apoCI/apoCIV/apoCII gene cluster are enhanced by multienhancer 2 (ME.