The formation of macrophage-derived foam cells is a typical feature of atherosclerosis (AS). Reverse cholesterol efflux (RCT) is one of important factors for the formation of macrophage foam cells. In this study, macrophage form cells were induced by oxidized low density lipoprotein (ox-LDL) and then treated with different concentrations of ferulic acid, so as to observe the effect of ferulic acid on the intracellular lipid metabolism in the ox-LDL-induced macrophage foam cell formation, the cholesterol efflux and the mRNA expression and protein levels of ATP binding cassette transporter A1 (ABCA1) and ATP binding cassette transporter G1 (ABCG1) that mediate cholesterol efflux, and discuss the potential mechanism of ferulic acid in resisting AS. According to the findings, compared with the control group, the ox-LDL-treated group showed significant increase in intracellular lipid content, especially for the cholesterol content; whereas the intracellular lipid accumulation markedly decreased, after the treatment with ferulic acid. The data also demonstrated that the mRNA and protein expressions of ABCA1 and ABCG1 significantly increased after macrophage foam cells were treated with different concentrations of ferulic acid. In summary, ferulic acid may show the anti-atherosclerosis effect by increasing the surface ABCA1 and ABCG1 expressions of macrophage form cells and promoting cholesterol efflux.
ATP Binding Cassette Transporter 1 ; analysis ; genetics ; ATP Binding Cassette Transporter, Sub-Family G, Member 1 ; ATP-Binding Cassette Transporters ; analysis ; genetics ; Animals ; Cells, Cultured ; Cholesterol ; metabolism ; Coumaric Acids ; pharmacology ; Foam Cells ; drug effects ; metabolism ; Lipoproteins ; analysis ; genetics ; Mice

ATP Binding Cassette Transporter 1 ; ATP-Binding Cassette Transporters ; genetics ; metabolism ; Anticholesteremic Agents ; pharmacology ; Cell Line ; Drug Synergism ; Humans ; Macrophages ; cytology ; metabolism ; PPAR gamma ; metabolism ; Pravastatin ; pharmacology ; RNA, Messenger ; genetics ; metabolism ; Thiazolidinediones ; pharmacology ; Up-Regulation ; drug effects

OBJECTIVETo investigate the role of ATP-binding cassette transporter G1 (ABCG1) in endothelial dysfunction induced by high glucose.

METHODSHuman aortic endothelial cells (HAECs) were incubated in the presence of 5.6 or 30 mmol/L glucose for 24-72 h with or without a 2-h pretreatment with the LXR agonist 22(R)-hydroxycholesterol. Real-time PCR and Western blotting were used to measure the mRNA and protein expressions of ABCG1; the intracellular cholesterol efflux and endothelial nitric oxide synthase (eNOS) activity were measured by scintillation counting.

RESULTSHigh glucose time-dependently suppressed ABCG1 expression and cholesterol efflux to HDL in HAECs. High glucose also decreased eNOS activity. ABCG1 down-regulation induced by high glucose, along with decreased cholesterol efflux and eNOS activity, was abolished by treatment of the cells with the LXR agonist.

CONCLUSIONEndothelial dysfunction induced by high glucose is associated with decreased ABCG1 expression.

ATP Binding Cassette Transporter, Sub-Family G, Member 1 ; ATP-Binding Cassette Transporters ; genetics ; metabolism ; Aorta ; cytology ; Cell Line ; Down-Regulation ; drug effects ; Endothelial Cells ; cytology ; metabolism ; physiology ; Glucose ; pharmacology ; Humans

OBJECTIVETo investigate the role of high glucose in the expression of ATP-binding cassette (ABC) transporters A1 (ABCA1) and G1 (ABCG1) in human vascular smooth muscle cells (VSMCs) and its possible mechanisms.

METHODSVSMCs were incubated in the presence of glucose at the concentrations ranging from 5 to 30 mmol/L for 1 to 7 days, and real-time PCR and Western blotting were used to measure the mRNA and protein expressions of ABCA1 and ABCG1. The effects of cells pretreatment with antioxidant NAC (10 mmol/L) and nuclear factor-kappaB (NF-kappaB) inhibitors BAY 11-7085 (10 micromol/L) and TPCK (10 micromol/L) were also tested on ABCA1 and ABCG1 expressions.

RESULTSHigh glucose suppressed, in a time- and dose-dependent manner, ABCG1 expression in incubated human VSMCs, and this effect was abolished by pretreatment with the antioxidant and nuclear factor-kappaB (NF-kappaB) inhibitors, but ABCA1 expression was not significantly decreased in the presence of high glucose.

CONCLUSIONHigh glucose suppresses ABCG1 expression in human VSMCs possibly due to increased oxidative stress and NF-kappaB activation induced by high glucose.

ATP Binding Cassette Transporter 1 ; ATP Binding Cassette Transporter, Sub-Family G, Member 1 ; ATP-Binding Cassette Transporters ; biosynthesis ; genetics ; Aorta ; cytology ; Blotting, Western ; Cells, Cultured ; Dose-Response Relationship, Drug ; Down-Regulation ; Glucose ; pharmacology ; Humans ; Muscle, Smooth, Vascular ; cytology ; drug effects ; metabolism ; NF-kappa B ; metabolism ; Oxidative Stress ; drug effects ; RNA, Messenger ; biosynthesis ; genetics ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo observe the effects of ATP-binding cassette A1 (ABCA1) on intercellular cell adhesion molecule type 1 (ICAM-1), monocyte chemoattractant protein-1 (MCP-1) and interleukin-1beta (IL-1beta) in THP-1 macrophages stimulated with 8-Br-cAMP to identify a possible new mechanism that ABCA1 contributes to atherosclerogenesis (AS).

METHODSMonocytic THP-1 cells were cultured in the presence of 100 nmol/L phorbol myristate acetate (PMA) for 72 h to transform the cells into THP-1 macrophages. After the macrophages were stimulated with 8-Br-cAMP (final concentration 0.5 mmol/L) for 3, 6, 12 and 24 h respectively, the amounts of ABCA1, ICAM-1 and MCP-1 mRNA were examined by real-time fluorescent quantitative RT-PCR, and the protein amounts of ABCA1, ICAM-1, MCP-1 and IL-1beta were determined by Western blotting and enzyme-linked immunosorbent assay (ELISA). Phosphorothioate antisense oligonucleotides of ABCA1 were add into the culture media at a final concentration of 100 nmol/L and the experiments were repeated.

RESULTSABCA1, ICAM-1 and MCP-1 mRNA and protein and IL-1beta protein were increased in the macrophages after stimulation with 8-Br-cAMP for 6 and 12 h. The mRNA expressions of ABCA1, ICAM-1 and MCP-1 were decreased significantly at 3 and 6 h (P<0.01), and the protein expressions of ABCA1, ICAM-1, MCP-1 and IL-1beta declined significantly at 12 and 24 h (P<0.01) after transfection of the macrophages with antisense oligonucleotides of ABCA1.

CONCLUSIONABCA1 can increase the expressions of the inflammatory cytokines in THP-1 macrophages stimulated by 8-Br-cAMP and plays a role in the pathogenesis of AS.

8-Bromo Cyclic Adenosine Monophosphate ; pharmacology ; ATP Binding Cassette Transporter 1 ; ATP-Binding Cassette Transporters ; biosynthesis ; genetics ; Cell Line ; Chemokine CCL2 ; genetics ; metabolism ; Enzyme-Linked Immunosorbent Assay ; Humans ; Intercellular Adhesion Molecule-1 ; genetics ; metabolism ; Interleukin-1beta ; genetics ; metabolism ; Macrophages ; cytology ; drug effects ; metabolism ; Monocytes ; cytology ; drug effects ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Tetradecanoylphorbol Acetate ; pharmacology

OBJECTIVETo investigate the effects of rapamycin on cholesterol homeostasis of glomerular mesangial cells and the underlying mechanisms.

METHODSIntracellular cholesterol accumulation was measured by Oil Red O staining and high performance liquid chromatography. The effects of rapamycin on interleukin-1 beta (IL-1 beta)-induced mRNA and protein changes of low-density lipoprotein receptor (LDLR) and ATP-binding cassette transporter A1 (ABCA1) were assayed by quantitative real-time PCR and Western blot. Transient expressions of 3 types of mammalian target of rapamycin (mTOR), including mTOR-WT (wild type), mTOR-RR (rapamycin resistant, with kinase activity), and mTOR-RR-KD (rapamycin resistant, without kinase activity), were obtained by plasmid transfection.

RESULTSRapamycin had no significant influence on intracellular cholesterol concentration under normal condition, but it significantly decreased the intracellular cholesterol concentration in the presence of IL-1 beta. Rapamycin dose-dependently suppressed the increased expression of LDLR induced by IL-1 beta and up-regulated the suppressed expression of ABCA1 caused by IL-1 beta. Transient expression of 3 types of mTOR all reduced ABCA1 mRNA expression significantly, which all could be overroded by rapamycin.

CONCLUSIONSRapamycin may contribute to the maintaining of glomerular mesangial cell intracellular cholesterol homeostasis under inflammatory state by both reducing cholesterol uptake and increasing cholesterol efflux. And the effect may be not completely mediated by mTOR.

ATP Binding Cassette Transporter 1 ; ATP-Binding Cassette Transporters ; genetics ; metabolism ; Animals ; Cell Line ; Cholesterol ; metabolism ; Homeostasis ; drug effects ; Humans ; Immunosuppressive Agents ; pharmacology ; Interleukin-1beta ; metabolism ; Mesangial Cells ; cytology ; drug effects ; metabolism ; Receptors, LDL ; genetics ; metabolism ; Signal Transduction ; physiology ; Sirolimus ; pharmacology

Traditional theories suggest that tumor growth occurs when all tumor cells work together and result in proliferation, so treatment has been mainly directed against the majority of the cells in tumor tissue, which often relapse, metastasize, and lead to treatment failure. As cancer stem cells have been successfully isolated from different tumor tissues, in-depth study of their function in relation to traditional cancer treatment faces enormous challenges. At the same time, a new theoretical basis has been provided for the in-depth study of tumorigenesis and the evaluation of prognosis of cancer therapy. Also, new ideas have been introduced for cancer therapy. Therefore, radical treatment of cancer can be achieved through killing cancer stem cells. This article reviews the research progress on cancer stem cells and their drug resistance.
ATP-Binding Cassette Transporters ; metabolism ; Animals ; Antineoplastic Agents ; pharmacology ; Apoptosis ; Cell Hypoxia ; Cell Transformation, Neoplastic ; DNA Repair ; DNA, Neoplasm ; genetics ; Drug Resistance, Multiple ; Drug Resistance, Neoplasm ; Humans ; Neoplasms ; genetics ; metabolism ; pathology ; Neoplastic Stem Cells ; drug effects ; pathology

We have investigated the effect of various forms of phosphodiester cytidine-phosphate-guanosine oligodeoxynucleotides (CpG ODNs) on the production of pro-inflammatory cytokines and related genes in RAW 264.7 macrophages. Treatment with the CpG ODNs increased the expression of tumor necrosis factor alpha (TNF-alpha), IL-6, and inducible nitric oxide synthase but not interleukin-1beta (IL-1beta). We also investigated the effect of CpG ODNs on the expression of ATP-binding cassette transporter A1 (ABCA1) and G1 (ABCG1) genes which are known to facilitate cholesterol efflux from macrophages for anti-atherosclerosis. CpG 2006 significantly reduced the levels of ABCG1 mRNA as determined by real-time polymerase chain reaction, whereas ABCA1 mRNA level was not changed. Western blot analysis further confirmed the reduction of ABCG1 protein expression by CpG 2006. In addition, we also determined the protein level of peroxisome proliferator activated receptor gamma (PPARgamma), which is recognized as a transcriptional activator of ABC transporters, was also reduced by CpG 2006. Thus, these results suggest that ABCG1 is specifically down-regulated by CpG 2006 in a PPARgamma-dependent manner in macrophages.
ATP-Binding Cassette Transporters/drug effects/genetics/*metabolism ; Animals ; Atherosclerosis/metabolism ; Cholesterol/metabolism ; Cytokines/drug effects/metabolism ; Gene Expression Regulation ; Inflammation/*metabolism ; Interleukin-1beta/drug effects/metabolism ; Interleukin-6/metabolism ; Lipoproteins/drug effects/genetics/*metabolism ; Macrophages/*cytology/*metabolism ; Mice ; Nitric Oxide Synthase/drug effects/metabolism ; Oligodeoxyribonucleotides/*pharmacology ; PPAR gamma/genetics/*metabolism ; Tumor Necrosis Factor-alpha/drug effects/metabolism

ATP-binding cassette transporter A1 (ABCA1) promotes cholesterol and phospholipid efflux from cells to lipid-poor apolipoprotein A-I (apoA-I), and plays a key role in the initial steps of the whole process of reverse cholesterol transport (RCT). Upregulation of ABCA1 is beneficial for atherosclerosis (AS) prevention and/or therapy, which indicated that ABCA1 was a target for anti-AS drug development. In the previous study, a high-throughput screening method was established using ABCA1p-LUC HepG2 cell line to find the upregulators of ABCA1. In the present study, compound 2030421B was found using this method, with EC50 of 0.50 microg x mL(-1). The compound was further identified as an upregulator of ABCA1 expression by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting analysis. Studies also showed that the 2030421B could induce apoA-I-mediated cholesterol efflux and inhibit lipids uptake into mouse peritoneal macrophages RAW264.7.
ATP Binding Cassette Transporter 1 ; ATP-Binding Cassette Transporters ; genetics ; metabolism ; Animals ; Anticholesteremic Agents ; administration & dosage ; chemistry ; pharmacology ; Apolipoprotein A-I ; metabolism ; Benzaldehydes ; administration & dosage ; chemistry ; pharmacology ; Biological Transport ; Cells, Cultured ; Cholesterol ; secretion ; Dose-Response Relationship, Drug ; Hep G2 Cells ; High-Throughput Screening Assays ; Humans ; Lipid Metabolism ; Lipids ; analysis ; Macrophages, Peritoneal ; cytology ; metabolism ; Mice ; Molecular Structure ; RNA, Messenger ; Up-Regulation ; drug effects

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can induce drug transporter genes such as the ATP-binding cassette G member 2 (ABCG2), which contributes to multidrug resistance. We investigated the effect of TCDD pretreatment on drug transporters induction from cancer cells of various origins. Cell viabilities after treatment of cisplatin were measured to evaluate acquiring cisplatin resistance by TCDD. Acquring cisplatin resistance was found only in cisplatin senstivie cancer cells including gastric SNU601, colon LS180, brain CRT-MG and lymphoma Jurkat cells which showed a significant increase in cell viability after combined treatment with TCDD and cisplatin. High increase of ABCG2 gene expression was found in SNU601 and LS180 cells with a mild increase in the expression of the ABCC3, ABCC5,and SLC29A2 genes in SNU601 cells, and of major vault protein (MVP) in LS180 cells. The AhR inhibitor kaempferol suppressed the upregulation of ABCG2 expression and reversed the TCDD-induced increase in cell viability in LS180 cells. However, in CRT-MG cells, other transporter genes including ABCC1, ABCC5, ABCA3, ABCA2, ABCB4, ABCG1, and SLC29A1 were up-regulated. These findings suggested the acquiring cisplatin resistance by TCDD associated with cancer cell-type-specific induction of drug transporters.
ATP-Binding Cassette Transporters/genetics/*metabolism ; Cell Line, Tumor ; Cell Survival/drug effects ; Cisplatin/*pharmacology ; Drug Resistance, Neoplasm/drug effects ; Equilibrative-Nucleoside Transporter 2/genetics/metabolism ; Humans ; Jurkat Cells ; K562 Cells ; Kaempferols/pharmacology ; Multidrug Resistance-Associated Proteins/genetics/metabolism ; Neoplasm Proteins/genetics/*metabolism ; RNA, Messenger/metabolism ; Receptors, Aryl Hydrocarbon/metabolism ; Tetrachlorodibenzodioxin/*pharmacology ; Up-Regulation/*drug effects ; Vault Ribonucleoprotein Particles/genetics/metabolism