共查询到20条相似文献，搜索用时 203 毫秒
1.
AIM: To explore the effect of anthocyanin on cholesterol efflux and elucidate its possible molecular mechanism. METHODS: Mouse Peritoneal macrophages were loaded with 50 mg/L AcLDL to induce macrophage-derived foam cells. Cholesterol efflux from macrophage-derived foam cells induced by anthocyanin was determined by enzymatic methods. PPAR-γ mRNA and protein expression in macrophage-derived foam cells was assayed by quantitative PCR and western blotting. RESULTS: Anthocyanins had the capacity of promoting cholesterol efflux from mouse peritoneal macrophage-derived foam cells and increased PPAR-γ mRNA and protein expression. CONCLUSION: Anthocyain-induced cholesterol efflux may be related to its enhancing PPAR-γ mRNA and protein expression. 相似文献
2.
AIM:To investigate the role of apolipoprotein E(ApoE) in cholesterol efflux mediated by ATP-binding cassette transporter A1(ABCA1) and ATP-binding cassette transporter G1(ABCG1). METHODS:RAW 264.7 cells were seeded in either 6-well or 24-well plates, and then incubated with 20 mg/L low-density lipoprotein receptor gene knockout(LDLr-/-) mouse lipoprotein 20 mg/L ApoE gene knockout(ApoE-/-) mouse lipoprotein or culture medium alone. The changes of intracellular lipid content were measured by transmission electron microscopy and enzymatic colorimetric method. The cholesterol efflux was determined by liquid scintillation. The mRNA and protein levels of ABCA1 and ABCG1 were detected by real-time PCR and Western blotting, respectively. RESULTS:The ApoE-/- mouse lipoprotein increased the content of intracellular cholesterol ester by 60% compared with the control cells. In addition, ApoE-/- mouse lipoprotein treatment decreased the cholesterol efflux to apolipoprotein A-I(ApoA-I) and high-density lipoprotein(HDL) compared with LDLr-/- mouse lipoprotein treatment. ApoE-/- mouse lipoprotein treatment inhibited the mRNA and protein levels of ABCA1 and ABCG1 compared with LDLr-/- mouse lipoprotein treatment. CONCLUSION:Apolipoprotein E plays an important role in the cholesterol efflux of macrophages, which is associated with its regulatory effect on the expression of ABCA1 and ABCG1. 相似文献
3.
AIM: In order to understand the role of chlamydia pneumoniae in the course of macrophages transformation into foam cells experiments with chlamydia pneumoniae standard strain AR-39 wese made. METHOD: C57 BL/6J Mouse peritoneal macrophages C57 BL/6J wese incubated 24 h, and they were divided into 6 groups to be incubated continually: A1~DMEM; A2~DMEM+10 IFUs/L AR-39; B1~DMEM+10mg/L LDL; B2~DMEM+10mg/L LDL+10 IFUs/L AR-39; C1~DMEM+10mg/L OxLDL;C2~DMEM+10mg/L OxLDL+10 IFUs/L AR-39. 72 h later, morphological changes of the cells were observed and of intracellular cholesterol of content was detected. RESULTS: 1、Morphological studies: there were no lipid particles in A1, A2 and B1 groups, but the lipid particles could be found in B2、C1 and C2 group, Among six groups, the most lipid particles were seen in C2 groups. 2、Biochemical detection:The ratio of cholesterol ester to total cholesterol was much higher than 50% in B2、C1 and C2 groups, but was less than 50% in A1、A2 and B1 groups. CONCLUSION: Chlamydia pneumoniae may have played a role in promoting C57 BL/6J mouse peritoneal macrophages into foam cells. 相似文献
4.
JIANG Pei YAN Peng-ke MO Zhong-cheng CAO Xuan TANG Chao-ke WANG Jiang-bo LIAO Duan-fang 《园艺学报》2005,21(6):1041-1045
AIM: To determine the effect of promoting cellular cholesterol efflux on the apoptosis of foam cells derived from monocytes. METHODS: RAW264.7 cells were incubated with 50 mg/L ox-LDL as a foam cell mode. The apoptosis rate of RAW264.7 cells was assayed by flow cytometry. Cellular lipid droplet was assayed by oil red staining. The rate of cellular cholesterol efflux was assayed with ［3H］ label cholesterol, and the content of cellular cholesterol were assayed by high performance liquid chromatography. RESULTS: After incubation with 50 mg/L ox-LDL for 48 h, the content of cellular cholesterol ester increased from (6.8±3.6) mg/g to (101.7±4.5) mg/g (P<0.05), but the rate of cholesterol efflux was only (5.2±2.1)%, and the apoptosis rate of RAW264.7 was increased from 8.14% to 42.6% (P<0.05). When treated with 200 mg/L HDL3 for 24 h, the rate of cellular cholesterol efflux were obviously increased, the apoptosis rate were decreased from 42.6% to 14.3% (P<0.05). Meanwhile, when treated with 10 mmol/L β-CD (a special compound for promoting cellular cholesterol efflux) for 24 h, the apoptosis rate was also decreased from 42.6% to 12.0%. CONCLUSION: HDL3 and β-CD inhibit the apoptosis of foam cells induced by oxidized LDL through promoting cellular cholesterol efflux. 相似文献
5.
AIM:Mast cells (MC) are present in the arterial intima,the site of atherogenesis. The present studies explore the effect of MC on cholesterol content,distribution and efflux in THP-1 macrophage-derived foam cells (THP-1FCs）. METHODS:THP-1FCs were incubated with high-density lipoproteins 3 (HDL3) in the absence or presence of mast cell granules (MCGs) harvested from compound 48/80-stimulated rat peritoneal MC. The intracellular cholesterol level,cholesterol effluxing capacity,ATP-binding cassette transporter A1(ABCA1) mRNA and HDL3 treated with MCGs were detected to characterize the role of MC on intracellular cholesterol. RESULTS:MCGs had high levels of cellular total cholesterol(TC),free cholesterol(FC) but not esterifed cholesterol(EC) compared to control group where the TC concentrations ranged from 527.3 mg/g to 917.9 mg/g cellular protein with EC accounting for 7.6% of the cholesterol. Cholesterol efflux was 14% less in MCGs group compared to control group. ABCA1 mRNA expression in MCG-treated THP-1FCs remained unchanged in 20 hours. In contrast,treatment of HDL3 with MCGs resulted in rapid degradation of the main HDL3 apoliproteins,apoA-Ⅰ. SDS-PAGE revealed that a minor polypeptide band with about 26 kD molecular mass appeared below the apoA-Ⅰband. Densitometric analysis of the gel demonstrated that ≈ 28% of apoA-Ⅰhad been degraded by the MCGs. CONCLUSION:These results indicate that MC decreases cholesterol efflux,increases cellular accumulation in TC and FC by depleting HDL3 and apoA-Ⅰ,but not by inhibiting ABCA1 mRNA expression. 相似文献
6.
AIM:These studies aimed at exploring the alteration of intracellular Ca2+ level in the course of macrophage-derived foam cell formation as well as its mechanism.METHODS:Foam-like cell was generated by peritoneal macrophage of C57BL/6J mouse, which is susceptible to atherosclerosis, incubated in 10 mg·L-1 oxidized low density lipoprotein for 96 hours. With the technique of Ca2+ fluorescent indicator and the assay of NADH-oxidizing coupling spectrum-alteration, the intracellular Ca2+ level and membranous Ca2+-ATPase activity of the above foam-like cell were determined.RESULTS:The foam-like macrophage Ca2+ level was 2.7 times higher than the control macrophage, and the former Ca2+-ATPase activity was 24% of the later.CONCLUSION:The results suggested that macrophage-derived foam cell formation was connected with slow Ca2+ entry or release, which possibly derived from long-lasting opening of membranous Ca2+ channels at the early stage and irreversible inactivating of membranous Ca2+ pump at the late stage. 相似文献
7.
8.
AIM To observe the changes of lipophagy during foam cells formation， and to determine the effect of lipophagy on the lipid content and cholesterol outflow of foam cells. METHODS Human THP-1 monocytes were induced by phorbol-12-myristate-13-acetate for 48 h to differentiate into macrophages， and then were incubated with 50 mg/L oxidized low-density lipoprotein （oxLDL） to form foam cells. Lipids in foam cell were stained by oil red O， and the lipid content was determined. The total cholesterol （TC） and free cholesterol （FC） levels in foam cells were measured by cholesterol testing kit. Cholesteryl ester （CE） and CE/TC ratio were calculated. The cholesterol efflux rate was detected by cholesterol efflux assay kit. The expression of autophagy-related proteins， including autophagy-related protein 5 （Atg5）， microtubule-associated protein 1 light chain 3 （LC3） and P62， were detected by Western blot. The colocalization of lipid droplets （LD） and LC3 was detected by immunofluorescence staining. The autophagy inducer rapamycin （Rap） or blocker 3-methyladenine （3MA） was used to intervene foam cells， and the expression of Atg5， LC3 and P62， the co-expression of LD and LC3， the cholesterol content and the cholesterol efflux rate were determined. RESULTS Formation of foam cells was observed at 24 h after stimulation with oxLDL at 50 mg/L， as indicated by intracellular CE/TC ratio exceeding 50%.Cholesterol efflux assay revealed that the cholesterol efflux rate increased within 24 h during foam cell formation but decreased after 48 h （P <0.05）. Western blot results displayed that the expression of Atg5 and LC3-II/LC3-I ratio were increased within 24 h of foam cell formation， but was deceased after 48 h （P <0.05）. The expression of P62 was decreased within 24 h but was increased at 48 h （P <0.05）. The colocalization of LD and LC3 was increased at 24 h but was decreased at 48 h after oxLDL stimulation. Treatment with Rap up-regulated the expression of Atg5 and LC3-II/LC3-I ratio， reduced the level of P62， increased the colocalization of LD and LC3， promoted the cholesterol efflux， anf reduced cholesterol content in foam cells （P <0.05）. On the contrary， 3MA inhibited the expression of Atg5， reduced LC3-II/LC3-I ratio， elevated the level of P62， decreased the colocalization of LD and LC3， reduced the outflow of cholesterol， increased the content of TC and CE， and elevated CE/TC ratio in foam cells （P <0.05）. CONCLUSION Lipophagy is enhanced at 24 h but decreased at 48 h during foam cell formation. Lipophagy inhibited foam cell formation by reducing cholesterol content and increasing cholesterol efflux. 相似文献
9.
AIM To explore the effects of nicotinic acid (NA) on lysosomal free cholesterol efflux in macrophages and its underlying mechanism. METHODS Macrophages induced from human monocytic leukemia cell line THP-1 by phorbol myristate acetate served as the cell model. Laser scanning confocal microscopy was applied to observe the effects of NA on lysosomal free cholesterol efflux in macrophages loaded with oxidized low-density lipoprotein (oxLDL). The influences of nicotinic acid adenine dinucleotide phosphate (NAADP) antagonist Ned-19, Ca2+ chelator BAPTA, liver X receptor α (LXRα ) siRNA and Niemann-Pick C1 protein (NPC1 ) siRNA on NA effects were also evaluated. RT-qPCR and Western blot were conducted to evaluate the influence of NA, Ned-19 and BAPTA on LXRα mRNA and NPC1 protein expression. RESULTS NA dose-dependently promoted lysosomal free cholesterol efflux in macrophages. This effect was markedly inhibited by Ned-19 and BAPTA. NA increased NPC1 protein and LXRα mRNA expression. These effects were also attenuated by Ned-19 and BAPTA remarkably. LXRα siRNA significantly inhibited the promoting effect of NA on NPC1 protein expression. Silencing of LXRα and NPC1 with siRNA remarkably abolished the effect of NA on lysosomal free cholesterol efflux. CONCLUSION NA promotes lysosomal free cholesterol efflux in macrophages. This effect may be mediated by the increased production of NAADP, which subsequently promotes Ca2+ release through lysosomal transient receptor potential mucolipin 1 (TRPML1) channel and finally up-regulates NPC1 protein expression via LXRα. 相似文献
10.
AIM:To study the action of ATP binding cassette transporter(ABC) A 1 on cholesterol efflux in THP-1 macrophage-derived foam cells.METHODS:After exposure of the cultured THP-1 macrophage-derived foam cells to 22(R)-hydroxycholesterol and 4, 4'-diisothiocyanostilbene-2, 2'-disulfonic acid (DIDS) at different concentration for 24 hours, cholesterol efflux and ABCA1 mRNA level were determined by FJ-2107P type liquid scintillator and reverse trancriptase-polymerase chaim reaction(RT-PCR), respectively.RESULTS:Oxidized LDL promoted cholesterol efflux in THP-1 macrophages and 22(R)-hydroxycholesterol increased cholesterol efflux in THP-1 macrophage-derived foam cells in a dose-dependent manner and DIDS inhibited cholesterol efflux in THP-1 macrophage-derived foam cells in a dose-dependent manner. Exposure of the cultured THP-1 macrophage-derived foam cells to 22(R)-hydroxycholesterol and DIDS at different concentration for 24 hours, resulted in increase and decrease in the expression of ABCA1 mRNA in THP-1 macrophage-derived foam cells in a dose-dependent manner, respectively.CONCLUSION:ABCA1 playes an important role in cholesterol efflux in THP-1 macrophage-derived foam cells. 相似文献
11.
AIM: To investigate the regulation of ghrelin on the expression of ATP-binding cassette transporter A1 and G1 (ABCA1/ABCG1)during the foam cell formation. METHODS: The human monocytic leukemia cell line (THP-1)was chosen in our study. The differentiation of THP-1 cells into macrophages was induced by using phorbol myristate acetate (PMA). Macrophages were then incubated with oxidized LDL (ox-LDL)to generate foam cells. Ghrelin of different concentrations were treated at different time points during foam cell formation. The ABCA1/ABCG1 protein and mRNA levels were detected by Western blotting and RT-PCR. The effect of variance of cholesterol content was measured by zymochemistry via-fluorospectrophotometer. RESULTS: Ghrelin reduced the content of lipid droplet in foam cells, and increased the efflux of intracellular cholesterol significantly. Ghrelin increased ABCA1 protein mass and mRNA level in dose-dependent manner. The changes of ABCG1 protein and mRNA level were the same as ABCA1. CONCLUSION: Ghrelin interfere atherosclerosis by up-regulating the expression of ABCA1 and ABCG1. 相似文献
12.
YANG Zhi-hong GONG Wei CHEN Feng-ling ZHOU Wen-bai ZHANG Shuo LI Lian-xi LIANG Wen-chang YANG Ye-hong HU Ren-ming 《园艺学报》2008,24(10):2029-2032
AIM: To study the effect of astragalus polysaccharides (Aps) on cholesterol efflux in THP-1 macrophage-derived foam cells. METHODS: After exposed to Aps at different doses, cholesterol efflux and ABCA1 protein levels in cultured THP-1 macrophage-derived foam cells were determined by a γ counter and flow cytometry, respectively. RESULTS: Aps increased cholesterol efflux in THP-1 macrophage-derived foam cells with dose dependent pattern and resulted in an increase in the expression of ABCA1 protein in THP-1 macrophage-derived foam cells. CONCLUSION: The increase in cholesterol efflux by Aps might be related to the up-regulation of ABCA1. 相似文献
13.
AIM:To study the characteristic of liver X receptor alpha (LXRα), it’s target gene expression and cholesterol efflux from human macrophages in coronary atherosclerotic disease (CAD) patients. METHODS:Human monocyte-derived macrophages from CAD patients and controls were collected. Before being detected apoA-I-mediated human monocyte-derived macrophage cholesterol efflux and LXRα and mRNA expression of its target gene, the macrophages were induced with or without TO-901317. 〖JP2〗RESULTS:Compared with control normal macrophage, the mRNA levels of LXRα and its target gene expression were changed, and the macrophage cholesterol efflux was decreased in CAD patients. After stimulationwith TO-901317, the reactive capacity of LXR was also decreased from human monocyte-derived macrophage of CAD patients. CONCLUSION:The changes of cholesterol efflux and some gene expression in macrophages may be the pathogenetic cause atherosclerosis, and macrophage LXR activity may offer potential therapeutic benefit in the treatment of CAD. 相似文献
14.
15.
2,3,5,4’-Tetrahydroxystilbene-2-O-β-D-glucoside protects against LPC-induced endothelial cell injury
AIM: To observe the protective effect of 2,3,5,4’-tetrahydroxystilbene-2-O-β-D-glucoside (TSG) on lysophosphatidylcholine (LPC)-induced vascular endothelial cell injury. METHODS: The 3rd and 4th generations of human umbilical vein endothelial cells (HUVECs) were cultured in vitro and propagated. The cells were randomly divided into 3 groups: control group, model group (LPC) and experimental group (TSG+LPC). The cells in control group were not treated with any reagent. To establish endothelial cell injury model, LPC was administered to HUVECs at concentration of 10 mg/L and incubated with the cells for 24 h. In TSG+LPC group, TSG was administered to HUVECs at concentrations of 10.0, 1.0 and 0.1 μmol/L 1 h before administration of LPC, and then the cells were incubated for 24 h. The cell viability, the content of asymmetric dimethyl arginine (ADMA) and NO, and apoptotic rate were detected. RESULTS: Compared with control group, ADMA content in the cell culture supernatants and apoptotic rate of the HUVECs in LPC group were significantly increased, while the NO content and cell viability were notably decreased. Compared with LPC group, ADMA content and apoptotic rate in TSG+LPC group was significantly decreased, while the NO content and cell viability were notably increased. CONCLUSION: TSG may protect LPC-injured vascular endothelial cells by attenuating the expression of ADMA and enhancing the production of NO, thus inhibiting apoptosis and increasing cell survival rate. 相似文献
16.
AIM To explore the anti-atherosclerotic mechanism of Wendan decoction based on formation of foam cells. METHODS The optimal concentrations of Wendan decoction without cytotoxity to cells were selected by MTT assay. After Wendan decoction treatment， the formation of foam cells was examined by oil red O staining. The cholesterol efflux， cholesterol level， free cholesterol level and cholesterol esterification rate were analyzed using cholesterol efflux assay， total cholesterol assay and free cholesterol assay. The expression levels of macrophage membrane proteins， including CD36， scavenger receptor class A （SR-A）， ATP-binding cassette transporter A1 （ABCA1） and scavenger receptor class B type I （SR-BI）， were quantified by Western blot. RESULTS The optimal concentrations of Wendan decoction without cytotoxity to the cells were 0~6 g/L. Wendan decoction at the concentrations of 1.5， 3 and 6 g/L were selected for the experiments. Wendan decoction at these concentrations inhibited the formation of foam cells induced by oxidized low-density lipoprotein （ox-LDL）， and reduced the accumulation of intracellular lipids in a concentration-dependent manner （P <0.05 or P <0.01）. Wendan decoction also reduced intracellular total cholesterol level， cholesterol ester level and cholesterol esterification rate （P <0.05 or P <0.01）， promoted efflux of intracellular cholesterol （P <0.01）， and decreased the protein level of CD36 in THP-1 cell-derived macrophages （P <0.01） in a concentration-dependent manner. Wendan decoction at the concentration of 6 g/L significantly reduced the protein level of SR-A in THP-1 cell-derived macrophages （P <0.05）. At the concentrations of 3 and 6 g/L， Wendan decoction significantly increased the protein levels of ABCA1 and SR-BI in THP-1 cell-derived macrophages （P <0.05 or P <0.01）. CONCLUSION Wendan decoction significantly inhibits ox-LDL-induced formation of foam cells by reducing cholesterol deposition and promoting cholesterol efflux， and its mechanism may be related to the down-regulation of CD36 and SR-A and the up-regulation of ABCA1 and SR-BI. 相似文献
17.
AIM: To investigate the effects of ghrelin on the expression of acyl coenzyme A:cholesterol acyltransferases-1 (ACAT-1) during the formation of foam cells. METHODS: The human monocytic leukemia cell line THP-1 was used in the study. The differentiation of THP-1 cells into macrophages was induced by phorbol 12-myristate 13-acetate (PMA). Macrophages were incubated with oxidized LDL (ox-LDL) to generate foam cells. Ghrelin of different concentrations were used during the formation of foam cells. The ACAT-1 protein and mRNA levels were detected by Western blotting and RT-PCR. The variance of cholesterol content was measured by zymochemistry via-fluorospectrophotometer. RESULTS: Ghrelin reduced the content of cholesterol ester in foam cells obviously. ACAT-1 protein and mRNA levels were also decreased. Ghrelin reduced ACAT-1 protein mass and mRNA level in a dose-dependent manner. CONCLUSION: Ghrelin might retard the formation of atherosclerosis via down-regulating the expression of ACAT-1. 相似文献
18.
SHAO Bo LI Ying WANG Xiao-yan ZHAI Xiao-tian TIAN Hua LIU Bo-yan ZHANG Ying SI Yan-hong QIN Shu-cun 《园艺学报》2000,36(10):1754-1760
AIM To verify whether Cordyceps militaris polysaccharide （CMPS） has the effect of promoting reverse cholesterol transport （RCT） in vitro and in vivo ， and to explore the underlying mechanism. METHODS For in vivo experiments， RCT efficiency was detected in cholesterol ester transporter transgene （CETP-tg） mice by isotope tracer technique， and the plasma lipid levels were measured by enzyme method. For in vitro experiments， the residual lipid content after cholesterol efflux in RAW264.7 macrophage-derived foam cells was tested by oil red O staining and total cholesterol （TC） kit. Western blot was used to analyze the protein expression of the molecules involved in cholesterol transport， uptake and transformation in the foam cells and mice liver. RESULTS After 4 weeks of intragastric administration of CMPS， the concentrations of TC， low-density lipoprotein cholesterol （LDL-C） and high-density lipoprotein cholesterol （HDL-C） in the plasma of CETP-tg mice were reduced by 24%， 23% and 22%， respectively. RCT efficiency of CETP-tg mice was accelerated and the appearance of 3H-cholesterol tracer in plasma， bile， intestine and feces was significantly increased in CMPS group. Meanwhile， the expression levels of cholesterol receptors scavenger receptor B1 （SR-B1） and LDL receptor （LDLR）， and cholesterol converting rate-limiting enzyme cholesterol 7α-hydroxylase A1 （CYP7A1） were upregulated by 105%， 71% and 58% in the liver of CMPS group， respectively. The results of in vitro experiments showed that CMPS preincubation promoted cholesterol efflux， decreased intracellular lipid and TC levels， and up-regulated the expression of peroxisome proliferator-activated receptor γ （PPARγ）-liver X receptor α （LXRα）-ATP-binding cassette transporter A1 （ABCA1）/ABCG1 signaling pathway related proteins in macrophage-derived foam cells. CONCLUSION CMPS promotes excess cholesterol efflux from peripheral macrophage-derived foam cells and accelerates its discharge through liver pathway. PPARγ-LXRα-ABCA1/ABCG1 pathway may be involved in the mechanism. 相似文献
19.
20.
AIM:To investigate the effect of tea-polyphenols (TP) on the activation of NF-κB and the expression of TGF-β1 mRNA in THP-1 cells (a human acute monocytic leukemia cell line). METHODS:THP-1 cells were incubated with the different concentrations of TP, VLDL, LDL or ox-LDL. In the THP-1 cellls, the nuclear malposition rate of NF-κB was detected with immunohistochemistry technique, the positive index of the TGF-β1 mRNA expression was detected by hybridization in situ, and accumulation of total cholesterol (TC) in cells incubated with 0.4-40 μg/L TP was determined with oxidase assay. RESULTS:The nuclear malposition rate of NF-κB, the positive index of the TGF-β1 mRNA expression and TC in THP-1 cells incubated with 0.4-40 μg/L of TP were lower than those with 0 μg/L of TP in TP-V group, TP-L group and TP-O (P＜0.05). The differences of these markers in THP-1 cells incubated with more than 40 μg/L TP in TP-V group, TP-L group and TP-O were not statistically significant, compared with TP-C group (P＞0.05). CONCLUSION:TP inhibited the activation of NF-κB, the expression of TGF-β1 mRNA and the foam cell formation in the mono-macrophage. 相似文献