Project description:Atherosclerosis is an inflammatory disease linked to elevated blood cholesterol levels. Despite ongoing advances in the prevention and treatment of atherosclerosis 1, cardiovascular disease remains the leading cause of death worldwide 2. Continuous retention of apolipoprotein B-containing lipoproteins in the subendothelial space causes a local overabundance of free cholesterol. Since cholesterol accumulation and deposition of cholesterol crystals (CCs) triggers a complex inflammatory response 3 4, we tested the therapeutic potential of increasing cholesterol solubility in experimental atherogenesis. Here we show that treatment of murine atherosclerosis with the cyclic oligosaccharide 2-hydroxypropyl-β-cyclodextrin (CD), a compound that solubilizes lipophilic substances, reduced atherosclerotic plaque size, cholesterol crystal load and promoted plaque regression even under continuing Western diet. CD solubilized CCs and promoted cholesterylester and oxysterol production in macrophages leading to liver X receptor (LXR)-mediated transcriptional reprogramming. CD increased cholesterol efflux from macrophages and substantially augmented reverse cholesterol transport in vivo. Furthermore, CD reduced proinflammatory cytokines in vivo and decreased macrophage responsiveness towards TLR and inflammasome activation. Since CD treatment in humans is safe and CD beneficially affects key pathogenetic factors in atherogenesis it may thus be used clinically to prevent or treat human atherosclerosis .
Project description:Atherosclerosis is an inflammatory disease linked to elevated blood cholesterol levels. Despite ongoing advances in the prevention and treatment of atherosclerosis 1, cardiovascular disease remains the leading cause of death worldwide 2. Continuous retention of apolipoprotein B-containing lipoproteins in the subendothelial space causes a local overabundance of free cholesterol. Since cholesterol accumulation and deposition of cholesterol crystals (CCs) triggers a complex inflammatory response 3 4, we tested the therapeutic potential of increasing cholesterol solubility in experimental atherogenesis. Here we show that treatment of murine atherosclerosis with the cyclic oligosaccharide 2-hydroxypropyl-β-cyclodextrin (CD), a compound that solubilizes lipophilic substances, reduced atherosclerotic plaque size, cholesterol crystal load and promoted plaque regression even under continuing Western diet. CD solubilized CCs and promoted cholesterylester and oxysterol production in macrophages leading to liver X receptor (LXR)-mediated transcriptional reprogramming. CD increased cholesterol efflux from macrophages and substantially augmented reverse cholesterol transport in vivo. Furthermore, CD reduced proinflammatory cytokines in vivo and decreased macrophage responsiveness towards TLR and inflammasome activation. Since CD treatment in humans is safe and CD beneficially affects key pathogenetic factors in atherogenesis it may thus be used clinically to prevent or treat human atherosclerosis .
Project description:Atherosclerosis is an inflammatory disease linked to elevated blood cholesterol levels. Since cholesterol retention and cholesterol crystals in arterial walls are key pathogenetic factors for atherogenesis, we assessed the therapeutic potential of increasing cholesterol solubility in vivo. Here we show that treatment of murine atherosclerosis with the cyclic oligosaccharide 2-hydroxypropyl-β-cyclodextrin (CD), a compound that solubilizes lipophilic substances, reduced atherosclerotic plaque size, cholesterol crystal (CC) load and promoted plaque regression even under continuing Western diet. CD solubilized CC and promoted cholesterylester and oxysterol production in macrophages leading to liver X receptor-mediated transcriptional reprogramming with increased cholesterol efflux and decreased inflammation. CD treatment may thus be used to increase cholesterol solubility and clearance to prevent or treat atherosclerosis.
Project description:The goal of this study is to determine whether PRMT2 plays a causal role in the impairment of atherosclerosis regression in diabetes. We examined the consequence of deleting PRMT2 in myeloid cells during the regression of atherosclerosis in normal and diabetic mice. We found significant impairment of atherosclerosis regression under normoglycemic conditions in mice lacking PRMT2 (Prmt2-/-) in myeloid cells that mimic the decrease in regression of atherosclerosis in WT mice under diabetic conditions. This was associated with increased plaque macrophage retention. PRMT2-deficient plaque CD68+ cells under normoglycemic conditions showed increased expression of genes involved in cytokine signaling and inflammation compared to WT cells by RNA seq. Thus, the loss of PRMT2 is causally linked to impaired atherosclerosis regression.
Project description:Atherosclerosis is an inflammatory disease linked to elevated blood cholesterol concentrations. Despite ongoing advances in the prevention and treatment of atherosclerosis, cardiovascular disease remains the leading cause of death worldwide. Continuous retention of apolipoprotein B-containing lipoproteins in the subendothelial space causes a local overabundance of free cholesterol. Because cholesterol accumulation and deposition of cholesterol crystals (CCs) trigger a complex inflammatory response, we tested the efficacy of the cyclic oligosaccharide 2-hydroxypropyl-β-cyclodextrin (CD), a compound that increases cholesterol solubility in preventing and reversing atherosclerosis. We showed that CD treatment of murine atherosclerosis reduced atherosclerotic plaque size and CC load and promoted plaque regression even with a continued cholesterol-rich diet. Mechanistically, CD increased oxysterol production in both macrophages and human atherosclerotic plaques and promoted liver X receptor (LXR)-mediated transcriptional reprogramming to improve cholesterol efflux and exert anti-inflammatory effects. In vivo, this CD-mediated LXR agonism was required for the antiatherosclerotic and anti-inflammatory effects of CD as well as for augmented reverse cholesterol transport. Because CD treatment in humans is safe and CD beneficially affects key mechanisms of atherogenesis, it may therefore be used clinically to prevent or treat human atherosclerosis.
Project description:Regression of atherosclerosis is an important clinical goal, however the pathways that mediate the resolution of atherosclerotic inflammation and reversal of plaques are poorly understood. Regulatory T cells (Tregs) have been shown to be atheroprotective, however numbers of these immunosuppressive cells decrease with disease progression. Using multiple independent mouse models of atherosclerosis regression, we demonstrate that an increase in plaque Tregs is a common signature of regressing plaques. To test if Tregs are required for the resolution of atherosclerotic inflammation and plaque regression during lipid-lowering therapy, we combined CD25 monoclonal antibody (PC61 mAb)-mediated Treg depletion with single-cell RNA-sequencing of immune cells in the plaque and conventional analyses of atherosclerosis. Single cell RNA-sequencing revealed that Tregs from aortic plaques shared some similarity with splenic Tregs, but were distinct from skin and colon Tregs supporting recent findings of tissue-dependent Treg heterogeneity. Furthermore, Tregs from progressing plaques expressed markers of natural Tregs derived from the thymus, whereas Tregs in regressing plaques lacked Nrp1 and Helios expression, suggesting that they are induced in the periphery during lipid lowering. Treatment of atherosclerotic mice with PC61 mAb effectively depleted Tregs in the blood and peripheral tissues, including plaques, and blocked the regression of atherosclerosis induced by apoB anti-sense oligonucleotides. Morphometric analyses revealed that control antibody-treated mice showed a 40% decrease in plaque burden and macrophage content under regression conditions, whereas PC61 mAb-treated mice showed no change in plaque size or inflammatory cell content compared to baseline. Moreover, Treg depletion enhanced inflammatory signaling and blocked tissue reparative functions of macrophages in the regressing plaque, including M2-polarization, efferocytosis and sensing of specialized pro-resolving lipid mediators. Together, these data establish essential roles for Tregs in the resolution of atherosclerotic inflammation and plaque remodeling during regression.
Project description:To further study the important genes related with the diagnosis and prognosis of atherosclerosis, we have employed whole genome microarray expression profiling as a discovery platform to identify genes with the atherosclerosis. we established a rabbit model of progression and regression of atherosclerosis through balloon injury and high-cholesterol diet and normal diet. Rabbit abdominal aortas from atherosclerosis among control, model group (progression) and recovery groups (regression) were collected. We found that the differentially expressed genes mainly enriched in four clusters and genes associated with inflammation and extracellular matrix were returned to or close to normal levels much earlier than the genes associated with metabolism and sarcoplasmic proliferation, they kept down-regulation or up-regulation for a long time after normal diet. Expression of four genes (LPL,BMP7,MCP2 and SST) from this signature was quantified in the same RNA samples by real-time PCR and maybe used as novel biomarkers and targets for improving the diagnosis and prognosis of atheroscleross in the future.