ATP-binding cassette transporters in progression and clinical outcome of pancreatic cancer: what is the way forward?

Pancreatic ductal adenocarcinoma(PDAC) is one of the most aggressive diseases and is characterized by high chemoresistance, leading to the lack of effective therapeutic approaches and grim prognosis. Despite increasing understanding of the mechanisms of chemoresistance in cancer and the role of ATPbinding cassette(ABC) transporters in this resistance, the therapeutic potential of their pharmacological inhibition has not been successfully exploited yet. In spite of the discovery of potent pharmacological modulators of ABC transporters, the results obtained in clinical trials have been so far disappointing, with high toxicity levels impairing their successful administration to the patients. Critically, although ABC transporters have been mostly studied for their involvement in development of multidrug resistance(MDR), in recent years the contribution of ABC transporters to cancer initiation and progression has emerged as an important area of research, the understanding of which could significantly influence the development of more specific and efficient therapies. In this review, we explore the role of ABC transporters in the development and progression of malignancies, with focus on PDAC. Their established involvement in development of MDR will be also presented. Moreover, an emerging role for ABC transporters as prognostic tools for patients' survival will be discussed, demonstrating the therapeutic potential of ABC transporters in cancer therapy.

Crosslink among cyclin-dependent kinase 9,ATP binding cassette transporter G2 and Beclin 1 in colorectal cancer

Colorectal cancer(CRC)ranks third in the number of cancers mainly because of the inability to diagnose it at an early stage.The pathogenesis of CRC is complicated,which is the result of the complex interaction of multiple genetic and environmental factors.Currently,one of the main treatments for CRC is chemotherapy.But the primary cause of CRC treatment failure is drug resistance.The expression of cyclin-dependent kinase 9(CDK9)was correlated with elevated autophagy levels in colon cancer,and high expression of CDK9 indicates a poor prognosis in CRC.The incidence of autophagy and the expressions of Beclin 1 and ATP binding cassette transporter G2 are different in left and right colon cancer,and autophagy may be involved in the occurrence of chemotherapy resistance.In this article,the roles of CDK9,ATP binding cassette transporter G2 and Beclin 1 in CRC were elucidated,emphasizing the linkages among them and providing potential therapeutic targets of CRC.

Inhibiting NF-κB increases cholesterol efflux from THP-1 derived-foam cells treated with AngⅡ via up-regulating the expression of ATP-binding cassette transporter A1

Objective： To study the role of nuclear factor-kappa B（NF- κB） in cholesterol efflux from THP-1 derived-foam cells treated with Angiotensin Ⅱ（Ang Ⅱ ）. Methods：Cultured THP-1 derived-foam cells were treated with Ang Ⅱ or preincubated with tosyl-phenylalanine chloromethyl-ketone（TPCK） NF- κB inhibitor. The levels of activated NF- κB in the cells were examined by sandwich ELISA, Cellular cholesterol content was studied by electron microscopy scanning and zymochemistry via fluorospectrophotometer and cholesterol effiux was detected by scintillation counting technique. ABCA1 mRNA and protein were quantified by RT-PCR and Western blotting. Results：Addition of TPCK to the cells before Ang Ⅱ stimulation attenuated the response of NF- κB p65 nuclear translocation induced by Ang Ⅱ and showed no peak in foam cells group and caused a reduction in cholesterol content and an increase in cholesterol efflux by 24.1%（P〈 0.05） and 41.1%（P〈 0.05） respectively, when compared with Ang Ⅱ group. In accordance, the ABCA1 mRNA and protein were increased by 30% and 19%（P 〈 0.05） respectively, when compared with Ang Ⅱ group. Conclusion：Ang Ⅱ can downregulate ABCA1 in THP-1 derived-foam cells via NF- K B, which leads to less cholesterol effiux and the increase of cholesterol content with the consequence of the promotion of atherosclerosis.

ATP-binding cassette subfamily B member 1 (ABCB1) and subfamily C member 10(ABCC1O) are not primary resistance factors for cabazitaxel

Introduction:ATP-binding cassette subfamily B member 1(ABCB1) and subfamily C member 10(ABCCIO) proteins are efflux transporters that couple the energy derived from ATP hydrolysis to the translocation of toxic substances and chemotherapeutic drugs out of cells.Cabazitaxel is a novel taxane that differs from paclitaxel by its lower affinity for ATP-binding cassette(ABC) transporters.Methods:We determined the effects of cabazitaxel,a novel tubulin-binding taxane,and paclitaxel on paclitaxelresistant,ABCB1-overexpressing KB-C2 and LLC-MDR1-WT cells and paclitaxel-resistant,ABCC10-overexpressing HEK293/ABCC10 cells by calculating the degree of drug resistance and measuring ATPase activity of the ABCB1 transporter.Results:Decreased resistance to cabazitaxel compared with paclitaxel was observed in KB-C2,LLC-MDR1-WT,and HEK293/ABCC10 cells.Moreover,cabazitaxel had low efficacy,whereas paclitaxel had high efficacy in stimulating the ATPase activity of ABCB1,indicating a direct interaction of both drugs with the transporter.Conclusion:ABCB1 and ABCC10 are not primary resistance factors for cabazitaxel compared with paclitaxel,suggesting that cabazitaxel may have a low affinity for these efflux transporters.

Overexpression of the steroidogenic acute regulatory protein increases the expression of ATP-binding cassette transporters in microvascular endothelial cells(bEnd.3)

Objective:To determine the effect of steroidogenic acute regulatory protein(StAR) overexpression on the levels of adenosine triphosphate(ATP)-binding cassette transporter A1(ABCA1) and ATP-binding cassette transporter G1(ABCG1) in an endothelial cell line(bEnd.3).Methods:The StAR gene was induced in bEnd.3 cells with adenovirus infection.The infection efficiency was detected by fluorescence activated cell sorter(FACS) and fluorescence microscopy.The expressions of StAR gene and protein levels were detected by real-time polymerase chain reaction(PCR) and Western blot.The gene and protein levels of ABCA1 and ABCG1 were detected by real-time PCR and Western blot after StAR overexpression.Results:The result shows that StAR was successfully overexpressed in bEnd.3 cells by adenovirus infection.The mRNA and protein expressions of ABCA1 and ABCG1 were greatly increased by StAR overexpression in bEnd.3 cells.Conclusion:Overexpression of StAR increases ABCA1 and ABCG1 expressions in endothelial cells.

Novel understanding of ABC transporters ABCB1/MDR/P-glycoprotein, ABCC2/MRP2, and ABCG2/BCRP in colorectal pathophysiology

AIM: To evaluate ATP-binding cassette(ABC) transporters in colonic pathophysiology as they had recently been related to colorectal cancer(CRC) development. METHODS: Literature search was conducted on Pub Med using combinations of the following terms: ABC transporters, ATP binding cassette transporter proteins, inflammatory bowel disease, ulcerative, colitis, Crohns disease, colorectal cancer, colitis, intestinal inflammation, intestinal carcinogenesis, ABCB1/P-glycoprotein(P-gp/CD243/MDR1), ABCC2/multidrug resistance protein 2(MRP2) and ABCG2/breast cancer resistance protein(BCRP), Abcb1/Mdr1 a, abcc2/Mrp2, abcg2/Bcrp, knock-out mice, tight junction, membrane lipid function. RESULTS: Recently, human studies reported thatchanges in the levels of ABC transporters were early events in the adenoma-carcinoma sequence leading to CRC. A link between ABCB1, high fat diet and gut microbes in relation to colitis was suggested by the animal studies. The finding that colitis was preceded by altered gut bacterial composition suggests that deletion of Abcb1 leads to fundamental changes of hostmicrobiota interaction. Also, high fat diet increases the frequency and severity of colitis in specific pathogenfree Abcb1 KO mice. The Abcb1 KO mice might thus serve as a model in which diet/environmental factors and microbes may be controlled and investigated in relation to intestinal inflammation. Potential molecular mechanisms include defective transport of inflammatory mediators and/or phospholipid translocation from one side to the other of the cell membrane lipid bilayer by ABC transporters affecting inflammatory response and/or function of tight junctions, phagocytosis and vesicle trafficking. Also, diet and microbes give rise to molecules which are potential substrates for the ABC transporters and which may additionally affect ABC transporter function through nuclear receptors and transcriptional regulation. Another critical role of ABCB1 was suggested by the finding that ABCB1 expression identifies a subpopulation of pro-inflammatory Th17 cells which were resistant to treatment with glucocorticoids. The evidence for the involvement of ABCC2 and ABCG2 in colonic pathophysiology was weak. CONCLUSION: ABCB1, diet, and gut microbes mutually interact in colonic inflammation, a well-known risk factor for CRC. Further insight may be translated into preventive and treatment strategies.

High-density lipoprotein and atherosclerosis: Roles of lipid transporters

Various previous studies have found a negative cor-relation between the risk of cardiovascular events and serum high-density lipoprotein(HDL) cholesterol levels. The reverse cholesterol transport, a pathway of choles-terol from peripheral tissue to liver which has several potent antiatherogenic properties. For instance, the particles of HDL mediate to transport cholesterol from cells in arterial tissues, particularly from atherosclerotic plaques, to the liver. Both ATP-binding cassette trans-porters(ABC) A1 and ABCG1 are membrane cholesterol transporters and have been implicated in mediating cholesterol effluxes from cells in the presence of HDL and apolipoprotein A-I, a major protein constituent of HDL. Previous studies demonstrated that ABCA1 and ABCG1 or the interaction between ABCA1 and ABCG1 exerted antiatherosclerotic effects. As a therapeutic approach for increasing HDL cholesterol levels, much focus has been placed on increasing HDL cholesterol levels as well as enhancing HDL biochemical functions. HDL therapies that use injections of reconstituted HDL, apoA-I mimetics, or full-length apoA-I have shown dramatic effectiveness. In particular, a novel apoA-I mi-metic peptide, Fukuoka University ApoA-I Mimetic Pep-tide, effectively removes cholesterol via specific ABCA1 and other transporters, such as ABCG1, and has an an-tiatherosclerotic effect by enhancing the biological func-tions of HDL without changing circulating HDL choles-terol levels. Thus, HDL-targeting therapy has significant atheroprotective potential, as it uses lipid transporter-targeting agents, and may prove to be a therapeutic tool for atherosclerotic cardiovascular diseases.

ABC efflux transporters at blood-central nervous system barriers and their implications for treating spinal cord disorders

The barriers present in the interfaces between the blood and the central nervous system form a major hurdle for the pharmacological treatment of central nervous system injuries and diseases.The family of ATP-binding cassette(ABC)transporters has been widely studied regarding efflux of medications at blood-central nervous system barriers.These efflux transporters include P-glycoprotein(abcb1),‘breast cancer resistance protein'(abcg2)and the various‘multidrug resistance-associated proteins'(abccs).Understanding which efflux transporters are present at the blood-spinal cord,blood-cerebrospinal fluid and cerebrospinal fluid-spinal cord barriers is necessary to determine their involvement in limiting drug transfer from blood to the spinal cord tissue.Recent developments in the blood-brain barrier field have shown that barrier systems are dynamic and the profile of barrier defenses can alter due to conditions such as age,disease and environmental challenge.This means that a true understanding of ABC efflux transporter expression and localization should not be one static value but instead a range that represents the complex patient subpopulations that exist.In the present review,the blood-central nervous system barrier literature is discussed with a focus on the impact of ABC efflux transporters on:(i)protecting the spinal cord from adverse effects of systemically directed drugs,and(ii)limiting centrally directed drugs from accessing their active sites within the spinal cord.

ATP结合盒转运蛋白家族与膀胱癌免疫治疗效果的关联性分析

目的基于IMvigor210和UNC-108(GSE176307)数据集分析探讨ATP结合盒(ABC)转运蛋白家族在膀胱癌患者免疫治疗中的临床应用价值。方法从IMvigor210数据集下载348例接受免疫治疗的膀胱尿路上皮癌患者的基因表达数据,将患者基于ABC转运蛋白家族基因表达水平进行共识聚类,分为聚类1和聚类2进行生存分析。通过单因素Cox回归分析筛选出对预后有影响的ABC转运蛋白家族基因,使用随机生存森林算法构建ABC评分预测模型,用于预测患者的生存期及免疫治疗反应,利用UNC-108数据集进一步验证模型的准确性。最后,采用ESTIMATE、ssGSEA算法评估患者的肿瘤微环境情况、oncoPredict算法预测患者对化疗药物顺铂的敏感性。结果筛选出9个ABC转运蛋白家族基因用于构建ABC评分预测模型。在IMvigor210队列中,Kaplan-Meier生存分析显示ABC评分低的患者总生存时间明显长于ABC评分高的患者(P<0.001);ABC评分模型对患者0.5年、1年和1.5年生存预测的受试者工作特征曲线下面积(AUC)分别为0.80、0.87和0.88;ABC评分对免疫治疗效果的预测能力的AUC为0.78,高于肿瘤突变负荷(AUC:0.72)和程序性死亡受体配体1(AUC:0.58)。ABC评分在UNC-108验证队列中也有着良好的预测效果。ABC评分与肿瘤微环境、多种免疫细胞、免疫表型、免疫评分、免疫检查点基因表达情况显著相关。结论ABC转运蛋白家族与膀胱癌的肿瘤微环境、免疫治疗效果关系密切,有望成为膀胱癌免疫治疗的新型生物标志物。

脂多糖通过核因子-κB途径下调泡沫细胞ATP结合盒转运体A1的表达

脂多糖(LPS)介导的免疫炎症反应与动脉粥样硬化(As)的发生密切相关,ATP结合盒转运体A1(ABCA1)促进细胞内胆固醇流出,具有抗As作用.观察了LPS对THP-1巨噬细胞源性泡沫细胞ABCA1表达及胆固醇流出的影响,并探讨TLR4/NF-κB信号途径和LXRs在此过程中的作用.THP-1巨噬细胞源性泡沫细胞经不同浓度LPS处理或者用LPS作用不同时间,以LPS单独或用NF-κB抑制剂对甲苯磺酰-L-苯丙氨酸氯甲基甲酮(TPCK)预处理细胞后再加入LPS处理.RT-PCR检测ABCA1、TLR4和LXRα mRNA的表达,Western blot检测ABCA1、LXRα及核内NF-κBp65蛋白的表达,液体闪烁计数器检测细胞内胆固醇流出,高效液相色谱分析细胞内总胆固醇、游离胆固醇和胆固醇酯含量.结果表明,LPS呈浓度和时间依赖性抑制ABCA1的表达,而增加TLR4 mRNA和核内NF-κBp65蛋白的表达,LPS使泡沫细胞内胆固醇流出减少,细胞总胆固醇、游离胆固醇与胆固醇酯增加,TPCK预处理后,LPS的这种作用被部分抑制,LXRα的表达不受LPS和TPCK的影响.这一结果提示,TLR4/NF-κB信号途径介导LPS对ABCA1表达及细胞内胆固醇流出的抑制作用,而LPS对ABCA1表达的调控不通过LXRα途径.

Ghrelin对THP-1源性泡沫细胞ATP结合盒转运子A1和G1表达的调控作用

目的:研究单核/巨噬细胞分化成为泡沫细胞过程中ghrelin对人ATP结合盒转运子A1和G1(ABCA1/ABCG1)表达的调控作用。方法:体外培养人源单核细胞系THP-1,由佛波酯(PMA)作用使其分化为巨噬细胞,后者可在氧化低密度脂蛋白(ox-LDL)存在条件下进一步转变为泡沫细胞。巨噬细胞加入不同浓度的Ghrelin预孵2h后再加入ox-LDL作用不同时间,油红O染色法观察细胞内脂滴含量,运用PT-PCR法检测ABCA1和ABCG1mRNA水平,Western blotting法检测ABCA1和ABCG1蛋白表达,采用酶法,通过荧光分光光度计检测细胞内外胆固醇含量并计算胆固醇流出率。结果:Ghrelin干预可明显减少细胞内脂滴的形成,显著增加胆固醇流出率,并能显著增加单核/巨噬细胞泡沫化过程中ABCA1和ABCG1mRNA水平和蛋白表达,且此作用呈浓度依赖性而不呈时间依赖性。结论:Ghrelin可能通过上调ABCA1和ABCG1转录翻译水平延缓动脉粥样硬化的发生。

血管紧张素Ⅱ对THP-1源性泡沫细胞ATP结合盒转运子A1的影响

目的:以THP-1源性泡沫细胞为研究对象,探讨血管紧张素Ⅱ(AngⅡ)对THP-1源性泡沫细胞ATP结合盒转运子A1(ABCA1)表达、细胞内胆固醇含量及胆固醇流出的影响。方法:运用逆转录-多聚酶链反应(RT-PCR)和W estern b lotting分别检测AngⅡ对ABCA1 mRNA与ABCA1蛋白表达的影响,采用酶法,通过荧光分光光度计检测细胞内胆固醇含量,应用液体闪烁计数仪检测胆固醇流出的变化。结果:AngⅡ能引起THP-1源性泡沫细胞胆固醇含量显著升高(P<0.05)、ABCA1表达显著减少(P<0.05),AngⅡ受体拮抗剂厄贝沙坦(Irb)能显著减少细胞内胆固醇含量(P<0.05)、促进细胞内胆固醇流出及减轻AngⅡ对ABCA1的抑制作用(P<0.05)。结论:AngⅡ有通过其受体抑制ABCA1表达,促进泡沫细胞形成,加速动脉粥样硬化的作用。

ATP结合盒转运体G1与动脉粥样硬化的研究进展

ATP结合盒转运体G1(ABCG1)是人类ATP结合盒转运体超家族的成员之一,可促进细胞内的胆固醇和磷脂外流,维持细胞脂质稳态平衡。ABCG1缺乏可参与泡沫细胞形成、内皮细胞功能紊乱和炎症反应等,进而影响动脉粥样硬化的形成和发展。但是无论在动物实验还是人体研究,ABCG1在动脉粥样硬化中的作用都有争议,本文针对ABCG1在动脉粥样硬化疾病中的研究进展进行综述。

The classification of ATP-binding cassette subfamily A member 3 mutations using the cystic fibrosis transmembrane conductance regulator classification system

Importance: The ATP-binding cassette subfamily A member 3 (ABCA3) protein plays a vital role in surfactant homeostasis. Mutations in the ABCA3 gene lead to the development of interstitial lung disease. In the most severe manifestation, mutations can lead to a fatal respiratory distress syndrome in neonates. ABCA3 belongs to the same ATP-binding cassette transporter superfamily as the cystic fibrosis transmembrane conductance regulator (CFTR), the gene that causes cystic fibrosis. Objective: To classify ABCA3 mutations in a manner similar to CFTR mutations in order to take advantage of recent advances in therapeutics. Methods: Sequence homology between the CFTR protein and the ABCA3 protein was established. The region of CFTR that is a target for the new potentiator class of drugs was of particular interest. We performed a literature search to obtain all published mutations that were thought to be disease causing. We classified these mutations using the established CFTR classification system. When possible, we drew on previous experimental classification of ABCA3 mutations. Results: Although the proteins share the same overall structure, only a 19％identity was established between CFTR and ABCA3. The CFTR therapeutic target region has a 22％ homology with the corresponding ABCA3 region. Totally 233 unique protein mutations were identified. All protein mutations were classified and mapped to a schematic diagram of the ABCA3 protein. Interpretation: This new classification system for ABCA3, based on CFTR classification, will likely aid further research of clinical outcomes and identification of mutation-tailored therapeutics, with the aim for improving clinical care for patients with ABCA3 mutations.

新转移相关基因ATP结合盒转运子E1在非小细胞肺癌中的表达及其意义

目的观察ATP结合盒转运子E1(ABCE1)的mRNA和蛋白在非小细胞肺癌组织、癌旁肺组织及转移淋巴结中的表达情况,探讨其在肺癌发生、发展中的意义及其与各种临床病理参数的关系。方法应用半定量逆转录聚合酶链反应、Westernblot和免疫组织化学SP法检测非小细胞肺癌组织、癌旁肺组织和转移淋巴结中ABCE1 mRNA和蛋白的表达情况。结果肺癌组织和转移淋巴结中ABCE1 mRNA和蛋白的表达量均高于癌旁肺组织(P<0.05),且mRNA和蛋白的表达呈正相关(r=3.992,P=0.001)。ABCE1蛋白的表达与患者年龄、性别、组织学分级、有无淋巴结转移及pTNM分期无关(P>0.05),与病理类型有关(P=0.036),在肺腺癌中的表达高于鳞癌;ABCE1 mRNA的表达与肺癌组织学分级有关(P=0.026)。结论 ABCE1的表达可能与非小细胞肺癌的侵袭和转移相关,在肺癌的发生发展过程中起到了重要作用,并可能成为潜在的肿瘤标记物及预后指标。

过氧化物酶体增殖体活化受体γ、肝脏X受体α、视黄酸X受体α活化对THP-1细胞ATP结合盒转运蛋白和CD36mRNA表达的影响

目的 :探讨核受体过氧化物酶体增殖体活化受体γ(PPARγ)、肝脏X受体α(LXRα)、视黄酸X受体α(RXRα)活化对THP1单核细胞ATP结合盒转运蛋白 (ABC1)和CD36mRNA表达影响的差异及其意义。方法 :体外培养的THP - 1单核细胞 ,经氟波酯 (PMA)诱导 4 8h ,使形成巨噬细胞 ,再分别用核受体PPARγ、LXRα、RXRα的相应配体曲格列酮、2 2 (R) -羟化胆固醇 [2 2 (R) -HC],9-顺式 -视黄酸 (9-CRA)作用 2 4h ,收集细胞 ,提取总RNA ,以 β -actin作内参 ,用RT -PCR法检测ABC1和CD36mRNA表达的变化。结果 :核受体PPARγ、LXRα、RXRα活化剂均可致ABC1mRNA表达增高 ,但对CD36mRNA的表达存在明显差异。PPARγ活化时CD36mRNA表达增高 ,LXRα活化时CD36mRNA表达并无明显增高 ,而RXRα活化时CD36mRNA表达降低。结论 :核受体PPARγ、LXRα、RXRα活化对ABC1和CD36mRNA表达的影响存在差异 ,提示LXRα。

ATP结合盒转运子A1基因R219K多态性在不同饮食结构人群中的分布特征及其与血脂水平的关系

目的探讨腺苷三磷酸(ATP)结合盒转运子A1基因(ATP binding cassette transporter 1,ABCA1)R219K多态性在不同饮食结构人群中的分布及其与血脂的关系。方法用聚合酶链式反应-限制性片段长度多态性(PCR-RFLP)方法测定ABCA1基因多态性。分析不同基因的频率在不同饮食结构人群的分布特点及其与血脂的关系。结果不同饮食结构的人群的ABCA1基因R219K的多态性位点存在RR、RK、KK型3种基因型,基因频率在不同饮食结构人群中的分布无差异性。K等位基因携带者的高密度脂蛋白胆固醇(High-density lipoprotein,HDL-C)水平高于RR基因型(P<0.05),KK型总胆固醇(Total Cholesterol,TC)水平低于RR型(P<0.05)。结论K等位基因可能产生有益的临床血脂谱。

高糖通过氧化应激及NF-κB通路抑制血管平滑肌细胞ATP结合盒转运体G1的表达

目的探讨高糖对人血管平滑肌细胞(VSMCs)表面介导细胞内胆固醇逆向转运的ATP结合盒(ABC)转运体ABCA1和ABCG1表达的影响及可能机制。方法VSMCs分别与不同浓度的D-葡萄糖(5～30mmol/L)孵育1～7d,realtime PCR及Western blot方法检测葡萄糖对VSMCs的ABCA1和ABCG1 mRNA和蛋白水平的影响,以及高糖干预的VSMCs经抗氧化剂NAC和NF-κB抑制剂Bay11-7085、TPCK作用后,ABC转运体表达的变化。结果高糖可时间和浓度依赖性地抑制VSMCs的ABCG1 mRNA和蛋白水平的表达,而对ABCA1的表达影响不明显。抗氧化剂和NF-κB抑制剂几乎可完全逆转高糖对ABCG1 mRNA表达的抑制。结论高糖可抑制VSMCs表面促进胆固醇流出的重要受体ABCG1表达,其作用机制可能与高糖增加的氧化应激和活化的NF-κB信号通路有关。

血管紧张素(1-7)和血管紧张素Ⅱ对THP-1巨噬细胞ATP结合盒转运子A1表达及胆固醇外流的影响

目的探讨血管紧张素(1-7)[Ang(1-7)]及血管紧张素Ⅱ(AngⅡ)对THP-1巨噬细胞ATP结合盒转运子A1(ABCA1)表达及胆固醇外流的影响。方法将诱导分化的巨噬细胞随机分为对照组、AngⅡ组、Ang(1-7)组、AngⅡ+不同浓度Ang(1-7)组、AngⅡ+Ang(1-7)+A-779组,分别运用RT-PCR及Western blot方法检测AB-CA1 mRNA及蛋白的表达,液体闪烁计数仪检测胆固醇流出的变化。结果与对照组相比,AngⅡ可抑制ABCA1mRNA(0.471±0.036比0.857±0.053,P<0.05)及蛋白(0.473±0.029比0.652±0.031,P<0.05)的表达,减少胆固醇外流(8.937±0.353比13.942±0.478,P<0.05);而Ang(1-7)促进ABCA1 mRNA(0.949±0.087比0.857±0.053,P<0.05)及蛋白(0.722±0.045比0.652±0.031,P<0.05)的表达,增加了胆固醇外流(15.477±0.882比13.942±0.478,P<0.05),且呈剂量依赖性地减弱AngⅡ的抑制作用(P<0.05);ABCA1 mRNA及蛋白的表达和胆固醇外流A-779组与AngⅡ组比较差异无统计学意义(0.472±0.063比0.471±0.036、0.515±0.048比0.473±0.029及9.309±0.333比8.937±0.353,P>0.05)。结论 AngⅡ可抑制巨噬细胞ABCA1的表达、减少胆固醇外流;Ang(1-7)通过其特异性受体MAS受体介导拮抗AngⅡ抑制巨噬细胞ABCA1的表达,促进胆固醇流出,进而对动脉粥样硬化的发生发展起保护作用。