Project description:Background: Elevated plasma cholesterol promotes the formation of atherosclerotic lesions in which monocyte-derived lipid-laden macrophages are frequently found. To analyze, if circulating monocytes already show increased lipid content and differences in lipoprotein metabolism, we compared monocytes from patients with Familial Hypercholesterolemia (FH) with those from healthy individuals. Methods: Cholesterol and oxidized cholesterol metabolite serum levels of FH and of healthy, gender/age matched control subjects were measured by combined gas chromatography ? mass spectroscopy. Monocytes from patients with FH and from healthy subjects were isolated by antibody-assisted density centrifugation. Gene expression profiles of isolated monocytes were measured using Affymetrix HG-U 133 Plus 2.0 microarrays. We compared monocyte gene expression profiles from FH patients with healthy controls using a Welch T-test with correction for multiple testing (p < 0.05; Benjamini Hochberg correction, False Discovery Rate = 0.05). The differential expression of FH associated genes was validated at the mRNA level by qRT-PCR and/or at the protein level by Western Blot or flow cytometry. Functional validation of monocyte scavenger receptor activities were done by binding assays and dose/time dependent uptake analysis using native and oxidized LDL. Results: Using microarray analysis we found in FH patients a significant up-regulation of 1,617 genes and a down-regulation of 701 genes compared to monocytes from healthy individuals. These include genes of proteins that are involved in the uptake, biosynthesis, disposition, and cellular efflux of cholesterol. In addition, plasma from FH patients contains elevated amounts of sterols and oxysterols. An increased uptake of oxidized as well as of native LDL by FH monocytes combined with a down-regulation of NPC1 and ABCA1 explains the lipid accumulation observed in these cells. Conclusion: Our data demonstrate that circulating FH monocytes show differences in cell physiology that may contribute to the early onset of atherosclerosis in this disease. Keywords: Micro-array analysis, cell type comparison,
Project description:Atherosclerosis is characterized by thickening of the arterial wall and is the primary cause of the coronary artery disease and cerebrovascular disease, two of the most common causes of illness and death worldwide. One of the leading risk factors for development of atherosclerosis is familial hypercholesterolemia. Familial hypercholesterolemia is an autosomal dominant disorder, which is caused by mutations mainly located in the low-density lipoprotein receptor (LDLR) gene. It is characterized by elevated levels of low-density lipoprotein cholesterol, the presence of tendon xanthomas, and premature cardiovascular disease. Aim of this study was to find atherosclerotic markers in white blood cells of patients compared to healthy controls. None of these patients exhibited symptoms of atherosclerosis by standard diagnostic methods; however, transcriptome analysis of blood RNA indicated changes in ubiquitin proteolysis and cell adhesion system as expected in initiation steps of atherosclerosis. Experiment Overall Design: Five patients diagnosed with Familial hypercholesterolemia and five age, sex, BMI and smoking status matched controls contributed blood from which total RNA from white blood cells was isolated. RNA samples were analyzed using Affymetrix microarrays and two groups were compared for differentially expressed genes.
Project description:Atherosclerosis is the major cause of death in industrialized countries. This disease has initially been characterized as a lipid disorder, but current concepts argue for an inflammatory disease, which develops in the background of hypercholesterolemia and other risk factors. In response to initial events of atherosclerosis formation, such as LDL-deposition in the subendothelial space, monocytes and T cells interact with the vessel wall. However, little is known about the properties and the behavior of these cells in this context. Using familial hypercholesterolemia (FH) as a model we demonstrate substantial differences in the gene expression of freshly isolated human monocytes and T lymphocytes. In FH monocytes we found an increased uptake of oxidized LDL, elevated amounts of scavenger receptors and adhesion molecules, and differences in the regulation of intracellular lipoprotein metabolism compared to monocytes from healthy individuals. Furthermore, the monocyte subpopulation of CD14+/CD16+ cells is less frequent in FH but exhibits significantly higher levels of CD11c and CD29 which increases the likelihood for their transmigration through the endothelial layer. The presence of increased amounts of CD69 in T lymphocytes from FH patients suggests that these cells are more activated than control cells. Our results indicate that some important steps of atherosclerosis formation already take place in circulating blood cells which extends current atherosclerosis models to the plasma compartment. Keywords: atherosclerosis, T cells, Familial Hypercholesterolemia
Project description:Atherosclerosis is the major cause of death in industrialized countries. This disease has initially been characterized as a lipid disorder, but current concepts argue for an inflammatory disease, which develops in the background of hypercholesterolemia and other risk factors. In response to initial events of atherosclerosis formation, such as LDL-deposition in the subendothelial space, monocytes and T cells interact with the vessel wall. However, little is known about the properties and the behavior of these cells in this context. Using familial hypercholesterolemia (FH) as a model we demonstrate substantial differences in the gene expression of freshly isolated human monocytes and T lymphocytes. In FH monocytes we found an increased uptake of oxidized LDL, elevated amounts of scavenger receptors and adhesion molecules, and differences in the regulation of intracellular lipoprotein metabolism compared to monocytes from healthy individuals. Furthermore, the monocyte subpopulation of CD14+/CD16+ cells is less frequent in FH but exhibits significantly higher levels of CD11c and CD29 which increases the likelihood for their transmigration through the endothelial layer. The presence of increased amounts of CD69 in T lymphocytes from FH patients suggests that these cells are more activated than control cells. Our results indicate that some important steps of atherosclerosis formation already take place in circulating blood cells which extends current atherosclerosis models to the plasma compartment. Experiment Overall Design: 25 monocytes samples: 5 homozygous FH, 7 heterozygous FH, 13 control participants
Project description:Atherosclerosis is characterized by thickening of the arterial wall and is the primary cause of the coronary artery disease and cerebrovascular disease, two of the most common causes of illness and death worldwide. One of the leading risk factors for development of atherosclerosis is familial hypercholesterolemia. Familial hypercholesterolemia is an autosomal dominant disorder, which is caused by mutations mainly located in the low-density lipoprotein receptor (LDLR) gene. It is characterized by elevated levels of low-density lipoprotein cholesterol, the presence of tendon xanthomas, and premature cardiovascular disease. Aim of this study was to find atherosclerotic markers in white blood cells of patients compared to healthy controls. None of these patients exhibited symptoms of atherosclerosis by standard diagnostic methods; however, transcriptome analysis of blood RNA indicated changes in ubiquitin proteolysis and cell adhesion system as expected in initiation steps of atherosclerosis.
Project description:Atherosclerosis is the major cause of death in industrialized countries. This disease has initially been characterized as a lipid disorder, but current concepts argue for an inflammatory disease, which develops in the background of hypercholesterolemia and other risk factors. In response to initial events of atherosclerosis formation, such as LDL-deposition in the subendothelial space, monocytes and T cells interact with the vessel wall. However, little is known about the properties and the behavior of these cells in this context. Using familial hypercholesterolemia (FH) as a model we demonstrate substantial differences in the gene expression of freshly isolated human monocytes and T lymphocytes. In FH monocytes we found an increased uptake of oxidized LDL, elevated amounts of scavenger receptors and adhesion molecules, and differences in the regulation of intracellular lipoprotein metabolism compared to monocytes from healthy individuals. Furthermore, the monocyte subpopulation of CD14+/CD16+ cells is less frequent in FH but exhibits significantly higher levels of CD11c and CD29 which increases the likelihood for their transmigration through the endothelial layer. The presence of increased amounts of CD69 in T lymphocytes from FH patients suggests that these cells are more activated than control cells. Our results indicate that some important steps of atherosclerosis formation already take place in circulating blood cells which extends current atherosclerosis models to the plasma compartment. Experiment Overall Design: 23 T cells samples: 3 homozygous FH, 7 heterozygous FH, 13 control participants
Project description:Innate immune memory, also refered to as trained immunity (TRIM) is the phenomenon whereby innate immune cells such as monocytes or macrophages undergo functional reprogramming after exposure to microbial components or metabolites. The cholesterol pathway is also involved in TRIM, and in this study we compared the transcriptomes of patients with hypercholesterolemia before and after statin treatment for 3 months.
Project description:The aim of the experiment was the analysis of hypercholesterolemia-induced myocardial microRNA alterations. Microarray analysis was applied to assess the expression changes resulted cholesterol-enriched diet. Male Wistar rats were fed with 2% cholesterol/0.25% cholate-enriched or standard diet for 12 weeks. microRNA of heart samples (n = 6) from both high cholesterol and normal diet groups were analysed.
Project description:The present gene expression array study of fluvastatin effects on monocytes from SLE patients show that fluvastatin has a global anti-inflammatory effect on monocytes, which includes attenuated expression of several proinflammatory cytokines, and regulated expression of molecules mediating lipoprotein signaling and cholesterol metabolism, as well as atherosclerosis and inflammatory signaling.