Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Atlas of miRNome variations in different dyslipidemic conditions: a study in C57Bl/6, Ldlr-KO, and Pcsk9-KO mice.

ABSTRACT: In this study, mice with different genotypes and fed diets with different lipid content were enrolled, aiming to set up an atlas of miRNA expression levels in different organs with a relevant role in lipid/lipoprotein metabolism. Specifically, three genotypes were investigated: C57Bl/6 mice as controls, together with mice knock-out (KO) for LDLr (low-density lipoprotein receptor) and for PCSK9 (proprotein convertase subtilisin/kexin type 9). LDLr and PCSK9 are both involved in LDL turnover, the former mediating LDL clearance [PMID: 19299327], the latter causing the degradation of the LDLr protein [PMID: 17080197]. As a result, LDLrKO mice, because of their impaired LDL catabolism, are hypercholesterolemic and prone to atherosclerosis development, particularly when fed high-fat, cholesterol-containing diets [PMID: 8349823; PMID: 8182121]. On the contrary, PCSK9KO mice, characterized by an accelerated LDL catabolism, are hypocholesterolemic and atherosclerosis resistant [PMID: 15805190]. miRNA expression was investigated in liver, intestine, aorta, white adipose tissue and brain of mice on both standard and Western diet.

ORGANISM(S): Mus musculus

PROVIDER: GSE227578 | GEO | 2023/09/06

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

The role of LDLR in intestinal inflammation

Project description:Low-density lipoprotein (LDL) is a risk factor for atherosclerosis, obesity, and other metabolic diseases, but its role in colitis is unknown. Here, we investigated the role of LDL in colitis by using LDL receptor deficient mice (Ldlr-/-). Wild-type and Ldlr-/- mice were fed with 3% DSS for 5 days and colons tissues were collected at day 8 post DSS treatment. We observed that Ldlr-/- mice are less susceptible to colitis. To understand the role of LDLR in colitis pathogenesis, we isolated RNA from colons of WT and Ldlr-/- mice and perfoemed RNA-seq. Our data show that the expression of inflamamtory genes are reduced in Ldlr-/- colons compared to wild-type. These data suggest that LDL is a potent endogenous trigger for intestinal inflammation.

2024-11-01 | GSE277062 | GEO

Interactome analysis of Adenylyl cyclase-associated protein 1

Project description:The direct inflammatory action of proprotein convertase subtilisin/kexin type 9 (PCSK9) is examined in vitro in monocytes and endothelial cells, as well as via an in vivo atherosclerosis animal model. PCSK9 exacerbates atherosclerosis in low-density lipoprotein receptor (LDLR)-/- mice, indicating an inflammatory effect mediated independently of the LDLR pathway. Here we show that Adenylyl cyclase-associated protein 1 (CAP1) is the main binding partner of PCSK9, serving a crucial role in the pro-inflammatory cascade of PCSK9 by enabling the induction of cytokines, the activation of Toll-like receptor 4 (TLR4), and the upregulation of scavenger receptors. We also present spleen tyrosine kinase (Syk) and protein kinase C delta (PKCδ) as pivotal mediators in the inflammatory cascade subsequent to PCSK9-CAP1 binding. In human peripheral blood mononuclear cells (PBMCs), serum PCSK9 levels are positively correlated with Syk, PKCδ, and p65 phosphorylation. Notably, the CAP1-fragment crystallizable region (CAP1-Fc) shows superior efficacy in mitigating PCSK9-mediated inflammatory signal transduction when compared with the PCSK9 inhibitor, evolocumab.

2024-06-16 | PXD047058 | Pride

PCSK9 deficiency results in a specific shedding of excess LDLR in female mice only: Role of hepatic cholesterol

Project description:PCSK9 promotes the lysosomal degradation of cell surface LDL receptor (LDLR). We analyzed how excess LDLR generated by PCSK9 deficiency is differently handled in male and female mice to possibly unveil the mechanism leading to the lower efficacy of PCSK9 mAb on LDL-cholesterol levels in women. Analysis of intact or ovariectomized PCSK9 knockout (KO) mice supplemented with placebo or 17β-estradiol (E2) demonstrated that female, but not male mice massively shed the soluble ectodomain of the LDLR in the plasma. Liver-specific PCSK9 KO or alirocumab-treated WT mice exhibit the same pattern. This shedding is distinct from the basal one and is inhibited by ZLDI-8, a metalloprotease inhibitor pointing at ADAM10/ADAM17. In PCSK9 KO female mice, ZLDI- 8 raises by 80 % the LDLR liver content in a few hours. This specific shedding is likely cholesterol-dependent: it is prevented in PCSK9 KO male mice that exhibit low intra-hepatic cholesterol levels without activating SREBP-2, and enhanced by mevalonate or high cholesterol feeding, or by E2 known to stimulate cholesterol synthesis via the estrogen receptor-α. Liver transcriptomics demonstrates that critically low liver cholesterol in ovariectomized female or knockout male mice also hampers the cholesterol-dependent G2/M transition of the cell cycle. Finally, higher levels of shed LDLR were measured in the plasma of women treated with PCSK9 mAb. PCSK9 knockout female mice hormonally sustain cholesterol synthesis and shed excess LDLR, seemingly like women. In contrast, male mice rely on high surface LDLR to replenish their stocks, despite 80 % lower circulating LDL.

2022-09-22 | GSE205008 | GEO

Urine-sample-derived human induced pluripotent stem cells as a model to study PCSK9-mediated autosomal dominant hypercholesterolemia

Project description:Proprotein convertase subtilisin kexin type 9 (PCSK9) is a critical modulator of cholesterol homeostasis. Whereas PCSK9 gain-of-function (GOF) mutations are associated with autosomal dominant hypercholesterolemia (ADH) and premature atherosclerosis, PCSK9 loss-of-function (LOF) mutations have a cardio-protective effect and in some cases can lead to familial hypobetalipoproteinemia (FHBL). However, limitations of the currently available cellular models preclude deciphering the consequences of PCSK9 mutation further. We aimed to validate urine-sample-derived human induced pluripotent stem cells (UhiPSCs) as an appropriate tool to model PCSK9-mediated ADH and FHBL. To achieve our goal, urine-sample-derived somatic cells were reprogrammed into hiPSCs by using episomal vectors. UhiPSC were efficiently differentiated into hepatocyte-like cells (HLCs). Compared to control cells, cells originally derived AQ3 from an individual with ADH (HLC-S127R) secreted less PCSK9 in the media (−38.5%; P=0.038) and had a 71% decrease (P<0.001) of low-density lipoprotein (LDL) uptake, whereas cells originally derived from an individual with FHBL (HLC-R104C/V114A) displayed a strong decrease in PCSK9 secretion (−89.7%; P<0.001) and had a 106% increase (P=0.0104) of LDL uptake. Pravastatin treatment significantly enhanced LDL receptor (LDLR) and PCSK9 mRNA gene expression, as well as PCSK9 secretion and LDL uptake in both control and S127R HLCs. Pravastatin treatment of multiple clones led to an average increase of LDL uptake of 2.19±0.77-fold in HLC-S127R compared to 1.38±0.49 fold in control HLCs (P<0.01), in line with the good response to statin treatment of individuals carrying the S127R mutation (mean LDL cholesterol reduction=60.4%, n=5). In conclusion, urine samples provide an attractive and convenient source of somatic cells for reprogramming and hepatocyte differentiation, but also a powerful tool to further decipher PCSK9 mutations and function.

2015-12-01 | GSE75545 | GEO

siRNAs induced long-term liver ApoB mRNA knockdown significantly lowers serum cholesterol in a mouse model with human-like serum lipids

Project description:Increased serum apoB and associated low density lipoprotein cholesterol (LDL) levels are well correlated with an increased risk of coronary disease. Apo E-/- and LDLr -/- mice have been extensively used for studies of coronary atherosclerosis. These animals show atherosclerotic lesions similar to those in humans, but their serum lipids are low in apoB containing LDL particles. We describe the development of a new mouse model with a human-like lipid profile. Ldlr+/- CETP+/- hemizygous mice carry a single copy of the human CETP transgene and a single copy of a LDL receptor mutation. To evaluate the apoB pathways in this mouse model, we used novel siRNAs formulated in lipid nanoparticles (LNPs). ApoB siRNAs induced up to 95% reduction of liver ApoB mRNA and serum apoB protein, and a significant lowering of serum LDL in Ldlr+/- CETP+/- mice. ApoB targeting is specific, dose dependent and shows lipid lowering effects for over three weeks. Although specific TGs were affected by ApoB KD, and the total plasma lipid levels were decreased by 70%, the overall lipid distribution did not change. Results presented here demonstrate a new mouse model for investigating additional targets within the ApoB pathways using the siRNA modality. Two oligoes specific for ApoB were used to knock down apoB expression in C57Bl6 or B6-Ldlr(tm1)Tg(APOA1-CETP) mice. Gene expression profiling was performed with Affymetrix Merck Custom Mouse 1.0 microarrays (GPL9734).

2010-11-22 | E-GEOD-23088 | biostudies-arrayexpress

siRNAs induced long-term liver ApoB mRNA knockdown significantly lowers serum cholesterol in a mouse model with human-like serum lipids

2010-11-22 | GSE23088 | GEO

NHP Liver treated with Vehicle or LXR Ligand

Project description:The LXR-regulated E3 ubiquitin ligase IDOL controls LDLR receptor stability independent of SREBP and PCSK9, but its relevance to plasma lipid levels is unknown. Here we demonstrate that the effects of the LXR–IDOL axis are both tissue- and species-specific. In mice, LXR agonist induces Idol expression in peripheral tissues but not in liver, and does not change plasma LDL levels. Accordingly, Idol-deficient mice exhibit elevated LDLR protein levels in peripheral tissues but not in the liver and have minimal change in plasma LDL levels. By contrast, LXR activation in cynomolgus monkeys induces hepatic IDOL expression, reduces LDLR protein, and raises plasma LDL levels. Knockdown of IDOL in monkeys with an antisense oligonucleotide blunts the effect of LXR agonist on LDL levels. These results implicate IDOL as a modulator of plasma lipid levels in primates and support further investigation into IDOL inhibition as a strategy for LDL lowering in humans.

2014-12-31 | GSE61381 | GEO

CSDE1 is a Post Transcriptional Regulator of the LDL Receptor

Project description:The low-density lipoprotein receptor (LDLR) controls cellular delivery of cholesterol and clears LDL from the bloodstream, protecting against atherosclerotic heart disease, the leading cause of death in the United States. We therefore sought to identify regulators of the LDLR beyond the targets of current clinical therapies and known causes of familial hypercholesterolemia. We show that Cold Shock Domain-Containing Protein E1 (CSDE1) enhances hepatic LDLR mRNA decay via its 3’ untranslated region and regulates atherogenic lipoproteins in vivo. Using parallel phenotypic genome-wide CRISPR interference screens in a tissue culture model, we found 40 specific regulators of the LDLR left unidentified by observational human genetics. Among these, we show that, in HepG2 cells, CSDE1 regulates the LDLR at least as strongly as the targets exploited by the best available clinical therapies: statins and PCSK9 inhibitors. Additionally, we show that hepatic gene silencing of Csde1 treats diet-induced dyslipidemia in mice similar to that of Pcsk9 silencing. Our results suggest the therapeutic potential of manipulating a newly identified factor in the post-transcriptional regulation of the LDLR mRNA for the prevention of cardiovascular disease. We anticipate that our approach of modeling a clinically relevant phenotype in a forward genetic screen, followed by mechanistic pharmacologic dissection and in vivo validation, will serve as a generalizable template for the identification of therapeutic targets in other human disease states.

2022-06-24 | GSE206846 | GEO

Impaired adult hippocampal neurogenesis in a mouse model of familial hypercholesterolemia: a role for the LDL receptor and cholesterol metabolism in adult neural precursor cells (LDLR Knockdown)

Project description:In familial hypercholesterolemia (FH), mutations in the low-density lipoprotein (LDL) receptor (LDLr) gene result in increased plasma LDL cholesterol. Clinical and preclinical studies revealed an association between FH and hippocampus-related memory and mood impairment. We here asked whether hippocampal pathology in FH might be a consequence of compromised adult hippocampal neurogenesis. We evaluated hippocampus-dependent behaviour and neurogenesis in adult C57BL/6JRj and LDLr-/- mice. Behavioural tests revealed that adult LDLr-/- mice showed reduced performance in a dentate gyrus (DG)-dependent metric change task. This phenotype was accompanied by a reduction in cell proliferation and adult neurogenesis in the DG of LDLr-/- mice, suggesting a potential direct impact of LDLr mutation on NPC. We thus investigated the effects of elevated cholesterol and the function of LDLr in neural precursor cells (NPC) isolated from adult C57BL/6JRj mice in vitro. Exposure of NPC to LDL as well as LDLr gene knockdown reduced proliferation and disrupted transcriptional activity of genes involved in endogenous cholesterol synthesis and metabolism. The LDL treatment also induced an increase in intracellular lipid storage. Functional analysis of differentially expressed genes revealed parallel modulation of distinct regulatory networks upon LDL treatment and LDLr knockdown. Together, these results suggest that high LDL levels and a loss of LDLr function, which are characteristic to individuals with FH, might contribute to a disease-related impairment in adult hippocampal neurogenesis and, consequently, cognitive functions.

2019-09-04 | GSE136797 | GEO

Impaired adult hippocampal neurogenesis in a mouse model of familial hypercholesterolemia: a role for the LDL receptor and cholesterol metabolism in adult neural precursor cells (LDL treatment)

2019-09-04 | GSE136792 | GEO