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Abstract LY86, also known as MD1, has been implicated in various pathophysiological processes including inflammation, obesity, insulin resistance, and immunoregulation. However, the role of LY86 in cholesterol metabolism remains incompletely understood. Several studies have reported significant up-regulation of LY86 mRNA in atherosclerosis; nevertheless, the regulatory mechanism by which LY86 is involved in this disease remains unclear. In this study, we aimed to investigate whether LY86 affects ox-LDL-induced lipid accumulation in macrophages. Firstly, we confirmed that LY86 is indeed involved in the process of atherosclerosis and found high expression levels of LY86 in human atherosclerotic plaque tissue. Furthermore, our findings suggest that LY86 may mediate intracellular lipid accumulation induced by ox-LDL through the SREBP2/HMGCR pathway. This mechanism could be associated with increased cholesterol synthesis resulting from enhanced endoplasmic reticulum stress response.

LY86, also known as MD1, has been implicated in various pathophysiological processes including inflammation, obesity, insulin resistance, and immunoregulation. However, the role of LY86 in cholesterol metabolism remains incompletely understood. Several studies have reported significant up-regulation of LY86 mRNA in atherosclerosis; nevertheless, the regulatory mechanism by which LY86 is involved in this disease remains unclear. In this study, we aimed to investigate whether LY86 affects ox-LDL-induced lipid accumulation in macrophages. Firstly, we confirmed that LY86 is indeed involved in the process of atherosclerosis and found high expression levels of LY86 in human atherosclerotic plaque tissue. Furthermore, our findings suggest that LY86 may mediate intracellular lipid accumulation induced by ox-LDL through the SREBP2/HMGCR pathway. This mechanism could be associated with increased cholesterol synthesis resulting from enhanced endoplasmic reticulum stress response. [ABSTRACT FROM AUTHOR]

Abstract Background Oxidized low-density lipoprotein (ox-LDL) can initiate and affect almost all atherosclerotic events including endothelial dysfunction. In this text, the role and underlying molecular basis of procyanidin B2 (PCB2) with potential anti-oxidant and anti-inflammatory activities in ox-LDL-induced HUVEC injury were examined. Methods HUVECs were treated with ox-LDL in the presence or absence of PCB2. Cell viability and apoptotic rate were examined by CCK-8 assay and flow cytometry, respectively. The mRNA and protein levels of genes were tested by RT-qPCR and western blot assays, respectively. Potential downstream targets and pathways of apple procyanidin oligomers were examined by bioinformatics analysis for the GSE9647 dataset. The effect of PCB2 on THP-1 cell migration was examined by recruitment assay. The effect of PCB2 on oxidative stress was assessed by reactive oxygen species (ROS) level, malondialdehyde (MDA) content, and mitochondrial membrane potential (MMP). Results ox-LDL reduced cell viability, induced cell apoptosis, and facilitated the expression of oxidized low-density lipoprotein receptor 1 (LOX-1), C-C motif chemokine ligand 2 (MCP-1), vascular cell adhesion protein 1 (VCAM-1) in HUVECs. PCB2 alleviated ox-LDL-induced cell injury in HUVECs. Apple procyanidin oligomers triggered the differential expression of 592 genes in HUVECs (|log2fold-change| > 0.58 and adjusted p-value

Abstract Background A high level of total cholesterol is associated with several lipid metabolism disorders, including atherosclerosis and cardiovascular diseases. ATP-binding cassette (ABC) transporter A1 (ABCA1) and miR-33-5p play crucial roles in atherosclerosis by controlling cholesterol efflux. While citrate is a precursor metabolite for lipid and cholesterol synthesis, little is known about the association between citrate synthase (CS) and cholesterol efflux. This study investigated the role of the miR-33-5p/ABCA1/CS axis in regulating cholesterol efflux in vascular endothelial cells (VECs). Materials and methods VECs were treated with oxidized low-density lipoprotein cholesterol (ox-LDL), or pretreated with plasmids overexpressing CS, ABCA1, siRNAs against CS and ABCA1, and an miR-33-5p inhibitor. Cell apoptosis, cellular senescence-associated β-galactosidase activity, inflammation, and cholesterol efflux were detected. Results Treatment with ox-LDL decreased ABCA1 and CS levels and increased miR-33-5p expression and apoptosis in dose-dependent manners. In contrast, treatment with the miR-33-5p inhibitor and ABCA1 and CS overexpression plasmids inhibited the above-mentioned ox-LDL-induced changes. In addition, treatment with ox-LDL decreased cholesterol efflux, induced aging, and promoted the production of inflammatory cytokines (i.e., IL-6 and tumor necrosis factor TNF-α), as well as the expression of Bax and Caspase 3 proteins in VECs. All these changes were rescued by miR-33-5p inhibition and ABCA1 and CS overexpression. The inhibition of ABCA1 and CS by siRNAs eliminated the effects mediated by the miR-33-5p inhibitor, and knockdown of CS eliminated the effects of ABCA1 on VECs. Conclusions This study demonstrated the crucial roles played by the miR-33-5p/ABCA1/CS axis in regulating cholesterol efflux, inflammation, apoptosis, and aging in VECs, and also suggested the axis as a target for managing lipid metabolism disorders.

Abstract Background The dysfunction and injury of human umbilical vein endothelial cells (HUVECs) are key events of atherosclerosis (AS). Atorvastatin (ATV) has been shown to play a protective role on endothelial cells. However, the associated molecular mechanisms remain not fully illustrated. Methods HUVECs were treated with oxidized low-density lipoprotein (ox-LDL) to mimic the pathological conditions of endothelial cell injury in AS. Cell injuries were assessed according to cell viability, cell apoptosis, cycle progression, oxidative stress and inflammatory responses using CCK-8 assay, flow cytometry assay or commercial kits. The expression of hsa_circ_0004831, miR-182-5p, and C-X-C motif chemokine 12 (CXCL12) mRNA was examined using quantitative real-time PCR (qPCR). The expression of CXCL12 protein was quantitated by western blot. The predicted target relationship between miR-182-5p and hsa_circ_0004831 or CXCL12 was verified by pull-down assay, dual-luciferase reporter assay or RIP assay. Results The expression of hsa_circ_0004831 was upregulated by ox-LDL but downregulated by ATV in HUVECs. ATV promoted cell viability and cell cycle progression but inhibited apoptosis, oxidative stress and inflammation in ox-LDL-treated HUVECs, while the role of ATV was partially reversed by hsa_circ_0004831 overexpression. MiR-182-5p was targeted by hsa_circ_0004831, and hsa_circ_0004831 overexpression-restored apoptosis, oxidative stress and inflammation were blocked by miR-182-5p restoration. Further, CXCL12 was targeted by miR-182-5p, and miR-182-5p inhibition-stimulated apoptosis, oxidative stress and inflammation were lessened by CXCL12 knockdown. Conclusion Hsa_circ_0004831-targeted miR-182-5p/CXCL12 regulatory network is one of the pathways by which ATV protects against ox-LDL-induced endothelial injuries.

Abstract Background Atherosclerosis (AS) is a chronic inflammatory disorder. The aim of our study was to explore the role of circular RNA (circRNA) transmembrane 7 superfamily member 3 (circTM7SF3) in AS progression. Methods Experiments were conducted using oxidized low-density lipoprotein (ox-LDL)-induced THP-1-derived macrophages and differentiated human monocyte-derived macrophages (hMDMs). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of circTM7SF3, its linear form TM7SF3, microRNA-206 (miR-206) and aspartyl (asparaginyl) β-hydroxylase (ASPH) messenger RNA (mRNA). Cell viability and apoptosis were examined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry. Cell inflammation was analyzed by measuring the production of tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) using enzyme-linked immunosorbent assay (ELISA) kits. Cell oxidative stress was assessed through analyzing the levels of oxidative stress markers using their corresponding commercial kits. Dual-luciferase reporter assay and RNA-pull down assay were used to confirm the interaction between miR-206 and circTM7SF3 or ASPH. The protein level of ASPH was examined by Western blot assay. Results CircTM7SF3 level was markedly increased in the serum samples of AS patients and ox-LDL-induced THP-1-derived macrophages compared with their matching counterparts. ox-LDL induced-damage in THP-1 cells was partly attenuated by the interference of circTM7SF3. MiR-206 was a downstream molecular target of circTM7SF3. Si-circTM7SF3-mediated effects in ox-LDL-induced THP-1-derived macrophages were partly ameliorated by the addition of anti-miR-206. MiR-206 directly interacted with ASPH mRNA. CircTM7SF3 silencing reduced the expression of ASPH partly through up-regulating miR-206 in THP-1-derived macrophages. ASPH overexpression partly counteracted the effects induced by miR-206 overexpression in ox-LDL-induced THP-1-derived macrophages. Conclusion CircTM7SF3 contributed to ox-LDL-induced injury in AS cell model through up-regulating the expression of ASPH via targeting miR-206.

Background: A high level of total cholesterol is associated with several lipid metabolism disorders, including atherosclerosis and cardiovascular diseases. ATP-binding cassette (ABC) transporter A1 (ABCA1) and miR-33-5p play crucial roles in atherosclerosis by controlling cholesterol efflux. While citrate is a precursor metabolite for lipid and cholesterol synthesis, little is known about the association between citrate synthase (CS) and cholesterol efflux. This study investigated the role of the miR-33-5p/ABCA1/CS axis in regulating cholesterol efflux in vascular endothelial cells (VECs).Materials and Methods: VECs were treated with oxidized low-density lipoprotein cholesterol (ox-LDL), or pretreated with plasmids overexpressing CS, ABCA1, siRNAs against CS and ABCA1, and an miR-33-5p inhibitor. Cell apoptosis, cellular senescence-associated β-galactosidase activity, inflammation, and cholesterol efflux were detected.Results: Treatment with ox-LDL decreased ABCA1 and CS levels and increased miR-33-5p expression and apoptosis in dose-dependent manners. In contrast, treatment with the miR-33-5p inhibitor and ABCA1 and CS overexpression plasmids inhibited the above-mentioned ox-LDL-induced changes. In addition, treatment with ox-LDL decreased cholesterol efflux, induced aging, and promoted the production of inflammatory cytokines (i.e., IL-6 and tumor necrosis factor TNF-α), as well as the expression of Bax and Caspase 3 proteins in VECs. All these changes were rescued by miR-33-5p inhibition and ABCA1 and CS overexpression. The inhibition of ABCA1 and CS by siRNAs eliminated the effects mediated by the miR-33-5p inhibitor, and knockdown of CS eliminated the effects of ABCA1 on VECs.Conclusions: This study demonstrated the crucial roles played by the miR-33-5p/ABCA1/CS axis in regulating cholesterol efflux, inflammation, apoptosis, and aging in VECs, and also suggested the axis as a target for managing lipid metabolism disorders. [ABSTRACT FROM AUTHOR]

Background: Atherosclerosis (AS) is a chronic inflammatory disorder. The aim of our study was to explore the role of circular RNA (circRNA) transmembrane 7 superfamily member 3 (circTM7SF3) in AS progression.Methods: Experiments were conducted using oxidized low-density lipoprotein (ox-LDL)-induced THP-1-derived macrophages and differentiated human monocyte-derived macrophages (hMDMs). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of circTM7SF3, its linear form TM7SF3, microRNA-206 (miR-206) and aspartyl (asparaginyl) β-hydroxylase (ASPH) messenger RNA (mRNA). Cell viability and apoptosis were examined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry. Cell inflammation was analyzed by measuring the production of tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) using enzyme-linked immunosorbent assay (ELISA) kits. Cell oxidative stress was assessed through analyzing the levels of oxidative stress markers using their corresponding commercial kits. Dual-luciferase reporter assay and RNA-pull down assay were used to confirm the interaction between miR-206 and circTM7SF3 or ASPH. The protein level of ASPH was examined by Western blot assay.Results: CircTM7SF3 level was markedly increased in the serum samples of AS patients and ox-LDL-induced THP-1-derived macrophages compared with their matching counterparts. ox-LDL induced-damage in THP-1 cells was partly attenuated by the interference of circTM7SF3. MiR-206 was a downstream molecular target of circTM7SF3. Si-circTM7SF3-mediated effects in ox-LDL-induced THP-1-derived macrophages were partly ameliorated by the addition of anti-miR-206. MiR-206 directly interacted with ASPH mRNA. CircTM7SF3 silencing reduced the expression of ASPH partly through up-regulating miR-206 in THP-1-derived macrophages. ASPH overexpression partly counteracted the effects induced by miR-206 overexpression in ox-LDL-induced THP-1-derived macrophages.Conclusion: CircTM7SF3 contributed to ox-LDL-induced injury in AS cell model through up-regulating the expression of ASPH via targeting miR-206. [ABSTRACT FROM AUTHOR]