Caprylic Acid Improves Lipid Metabolism, Suppresses the Inflammatory Response and Activates the ABCA1/p-JAK2/p-STAT3 Signaling Pathway in C57BL/6J Mice and RAW264.7 Cells / 生物医学与环境科学（英文）

OBJECTIVE@#This study aimed to investigate the effects of caprylic acid (C8:0) on lipid metabolism and inflammation, and examine the mechanisms underlying these effects in mice and cells.@*METHODS@#Fifty-six 6-week-old male C57BL/6J mice were randomly allocated to four groups fed a high-fat diet (HFD) without or with 2% C8:0, palmitic acid (C16:0) or eicosapentaenoic acid (EPA). RAW246.7 cells were randomly divided into five groups: normal, lipopolysaccharide (LPS), LPS+C8:0, LPS+EPA and LPS+cAMP. The serum lipid profiles, inflammatory biomolecules, and ABCA1 and JAK2/STAT3 mRNA and protein expression were measured.@*RESULTS@#C8:0 decreased TC and LDL-C, and increased the HDL-C/LDL-C ratio after injection of LPS. Without LPS, it decreased TC in mice ( P < 0.05). Moreover, C8:0 decreased the inflammatory response after LPS treatment in both mice and cells ( P < 0.05). Mechanistic investigations in C57BL/6J mouse aortas after injection of LPS indicated that C8:0 resulted in higher ABCA1 and JAK2/STAT3 expression than that with HFD, C16:0 and EPA, and resulted in lower TNF-α, NF-κB mRNA expression than that with HFD ( P < 0.05). In RAW 264.7 cells, C8:0 resulted in lower expression of pNF-κBP65 than that in the LPS group, and higher protein expression of ABCA1, p-JAK2 and p-STAT3 than that in the LPS and LPS+cAMP groups ( P < 0.05).@*CONCLUSION@#Our studies demonstrated that C8:0 may play an important role in lipid metabolism and the inflammatory response, and the mechanism may be associated with ABCA1 and the p-JAK2/p-STAT3 signaling pathway.

Isoflavones from Sojae Semen Praeparatum Regulate Lipid Metabolism in Atherosclerotic Mice Through PPARγ/LXRα/ABCA1 Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo study the effect of isoflavones from Sojae Semen Praeparatum （ISSP） on lipid metabolism in atherosclerotic mice， and decipher the underlying mechanism via the peroxisome proliferator-activated receptor gamma/liver X receptor alpha/ATP-binding cassette transporter A1 （PPARγ/LXRα/ABCA1） signaling pathway. MethodFifty ApoE-/- mice were randomly assigned into the model group， western medicine （atorvastatin calcium， 3.03 mg·kg-1） group， and low-， medium-， and high-dose ISSP （2.5， 5， 10 mg·kg-1， respectively） groups， with 10 rats in each group. Atherosclerosis model mice were established by bilateral ovariectomy and feeding high-fat diet. Another 10 ApoE-/- mice receiving ovariectomy and high-fat diet were taken as the sham group. Some mice died of postoperative infection， and finally 6 mice were included in each group. One week after operation， each group was administrated with corresponding drugs or equivalent amount of normal saline. After 12 weeks， the levels of triglyceride （TG）， total cholesterol （TC）， high-density lipoprotein cholesterol （HDL-C）， low-density lipoprotein cholesterol （LDL-C）， and non-esterified fatty acids （NEFAs） in serum and liver tissue were measured. The levels of tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6） in serum were detected by enzyme-linked immunosorbent assay （ELISA）. Hematoxylin-eosin （HE） staining and oil red O staining were used for observation of aortic plaque formation and liver lipid deposition. The mRNA and protein levels of PPARγ， LXRα， ABCA1， and ATP-binding cassette transporter G1 （ABCG1） in liver were determined by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot. ResultCompared with the sham group， the modeling of atherosclerosis increased the aortic plaque area （P<0.01）， elevated the serum TC， TG， LDL-C， TNF-α， and IL-6 levels （P<0.01）， decreased the level of HDL-C （P<0.01）， increased the liver index （P<0.05） and the levels of TC， TG， and NEFAs in liver （P<0.01）， and caused obvious hepatic fat vacuoles and lipid deposition. In addition， the modeling down-regulated the mRNA levels of PPARγ， LXRα， ABCA1 in liver （P<0.05， P<0.01），and regulated the mRNA and protein levels of ABCG1（P<0.05， P<0.01）. Compared with the model group， atorvastatin calcium and middle-， high-dose ISSP reduced the serum TC， TG， LDL-C， TNF-α， and IL-6 levels （P<0.01）， decreased the liver index （P<0.01）， alleviated the liver fat vacuoles and lipid deposition， and increased the levels of TC， TG， and NEFAs in the liver （P<0.05， P<0.01）. Furthermore， they up-regulated the mRNA and protein levels of PPARγ， LXRα， ABCA1， and ABCG1 in the liver （P<0.05， P<0.01）. ConclusionISSP may regulate lipid metabolism through PPARγ/LXRα/ABCA1 signaling pathway to down-regulate the expression of inflammatory cytokines in serum and alleviate liver lipid deposition， thereby suppressing the formation of atherosclerotic plaque.

Essential Oil from Alpinia zerumbet Rhizome Inhibits Macrophage-derived Foam Cell Formation Via Modulating Expression of CD36 and ABCA1 / 中国实验方剂学杂志

Objective::To clarify the inhibitory effect of essential oil from Alpinia zerumbet rhizome (EOFAZ) on oxidized low-density lipoprotein (ox-LDL)-induced transformation of macrophage into foam cell and explore its possible mechanism. Method::THP-1 monocyte was incubated with 100 μg·L-1 phorbol myristate acetate (PMA) to grow into macrophage, experiment was divided into 4 groups as follows, control group, model group (80 mg·L-1 ox-LDL), EOFAZ at low dose (80 mg·L-1 ox-LDL+ 4 μg·L-1 EOFAZ)and EOFAZ at high dose (80 g·L-1 ox-LDL+ 20 μg·L-1 EOFAZ). Mathye thiazolye telrazliurn (MTT) method was employed to examine the influence of EOFAZ on macrophage viability. Western blot was used to analyze the expression level of cluster of differentiation 36(CD36) and ATP-binding cassette transporter A1(ABCA1) protein in macrophage. Enzyme-linked immunosorbent assay (ELISA) was used to detect cholesteryl ester contents in macrophage. Oil red O staining was applied to determine the accumulation of lipids in macrophage. Result::EOFAZ showed non-toxic effect on macrophage. Compared to control group, macrophage in model group displayed higher level of cholesteryl ester and lipid droplet(P<0.01), as well as significant increasing of CD36 expression (P<0.01), but no effect on ABCA1 expression. EOFAZ notably reduced the contents of lipids and cholesteryl ester(P<0.01), down-regulated expression of CD36 and up-regulated expression of ABCA1 in macrophage in comparison with the model group(P<0.01), indicating that EOFAZ inhibited transformation of macrophage into foam cell. Conclusion::EOFAZ could inhibit ox-LDL-induced transformation of macrophage into foam cell, the underlying mechanism may involves its ability to increase CD36 expression and decrease ABCA1 expression in macrophage.

Effect and mechanism of astragalus polysaccharide on lipid metabolism of macrophages / 西安交通大学学报(医学版)

Objective: To explore the effect of astragalus polysaccharide (APS) on oxidized low-density lipoprotein (ox-LDL)-induced lipid metabolism of macrophages and its underlying mechanism. Methods: The small interfering RNA (siRNA) targeting ATP binding cassette transporter A1 (ABCA1) was transfected into RAW 264.7 macrophages. Then the cells were stimulated with various concentrations of APS (20 mg/L, 60 mg/L and 150 mg/L), followed by the incubation with 50 mg/L ox-LDL for 24 h. qRT-PCR and Western blot were used to investigate the expression of ABCA1 mRNA and protein. Oil red O was used to analyze the level of foam cells. Lipid accumulation level was assessed by high performance liquid chromatography. [3H]-cholesterol was used to evaluate cholesterol efflux. Results: APS dose-dependently inhibited ox-LDL-induced formation of macrophage-derived foam cell compared with those in control group (P<0.05). HPLC analysis confirmed that APS attenuated lipid accumulation in a dose-dependent manner based on the decrease in ratio of cholesterol ester (CE)/total cholesterol (TC), concomitant with up-regulation of cholesterol efflux (P<0.05), indicating that APS might inhibit lipid deposition in macrophage by enhancing reverse cholesterol transport. Further more, APS dose-dependently increased ABCA1 mRNA and protein levels (P<0.05). When silencing ABCA1 expression with its specific siRNA, APS-inhibited lipid accumulation was significantly up-regulated, accompanied with the down-regulation of cholesterol efflux (P<0.05). Conclusion: APS may regulate lipid metabolism of macrophages by ABCA1-mediated progress of reverse cholesterol transport. Therefore, this study provides a potential target for the treatment of cardiovascular diseases triggered by vulnerable plaque.

Effect of miRNA-33 on ABCA1/ABCG1 expression in RAW264.7 macrophage-derived foam cells after Hcy treatment / 中国病理生理杂志

AIM:To study whether homocysteine (Hcy) inhibits the expression of ATP-binding cassette transporter A1 (ABCA1) and ATP-binding cassette transporter G1 (ABCG1) by microRNA-33 (miRNA-33) signaling, and reduces the efficiency of reverse cholesterol transport (RCT).METHODS:RAW264.7 macrophages were induced by oxidized low-density lipoprotein (ox-LDL) to establish foam cell model.Oil red O staining was used to determine whether the model was established successfully.miRNA-33 mimics and miRNA-33 inhibitor were transfected into the cells by Lipofectamine 2000, and the cells were exposed to Hcy at concentration of 5 mmol/L for 24 h.The intracellular lipid droplets were observed by Oil red O staining.The expression of ABCA1 and ABCG1 at mRNA and protein levels was determined by real-time PCR and Western blot.The cellular cholesterol content was analyzed by HPLC, and effluent rate of cholesterol was detected by the method of liquid scintillation counting.RESULTS:Compared with blank control group, the lipid content in miRNA-33 mimics group was increased, and the expression of ABCA1 and ABCG1 at mRNA and protein levels was decreased (P<0.05).The intracellular cholesterol content was increased gradually (P<0.05) , and the cellular cholesterol efflux rate was gradually decreased (P<0.05) in miRNA-33 mimics group.Compared with blank control group, the testing results in miRNA-33 inhibitor group were the opposition of those in miRNA-33 mimics group (P<0.05).No difference of the above indexes among blank control group, miRNA-33 mimics-NC group and miRNA-33 inhibitor-NC group was observed.CONCLUSION:Hcy inhibits the mRNA and protein expression of ABCA1 and ABCG1 through miRNA-33 signaling, and reduces the efficiency of RCT in RAW264.7 macrophage-derived foam cells.

Research progress in small molecule drugs based on high-density lipoprotein for anti-atherosclerosis / 药学学报

A large number of epidemiological data have shown that the high-density lipoprotein cholesterol level is negatively related to atherosclerotic cardiovascular disease, suggesting that high-density lipoprotein may have the effect of anti-atherosclerosis. It may play the role of anti-atherosclerosis, through the promotion of cholesterol reverse transport, anti-inflammatory, antioxidant, and against thrombosis and fibrinolysis and so on. Among them, reverse cholesterol transport which is mainly regulated by apolipoprotein A-I, ATP-binding cassette transporter 1, liver X receptor and cholesteryl ester transfer protein, may play a major role in the maintenance of cholesterol homeostasis and reversing the course of atherosclerosis. These regulatory factors may be potential targets in high density lipoprotein-based drug discovery. In this review, these key proteins are discussed for the current status of small molecule drugs against atherosclerosis.

Study on the expression of ABCA1,PPAR,SREBP,ADPN and LXR α in patients with type 2 diabetes mellitus / 国际检验医学杂志

Objective To investigate the value of the expression of Adenosine Triphosphate (ATP) binding cassette transporter A1 (ABCA1),peroxisome proliferator activated receptor γ(PPARγ) and sterol regulato-ry element binding protein (SREBP),adiponectin (ADPN) and liver X recepto α(LXRα) in type 2 diabetic pa-tients.Methods 71 patients with type 2 diabetes received in the hospital from June 2015 to June 2017 were se-lected as the observation group,and 60 healthy persons who underwent the health assessment from June 2015 to June 2017 were selected as the control group.Peripheral venous blood was collected from patients with an empty stomach in the morning,serum was isolated and serum human ADPN content were measured by radio-immunoassay.The levels of serum ABCA1,PPAR γ,SREBP and LXR α were measured by Enzyme linked im-munosorbent assay.Results The serum levels of ABCA1 and ADPN in the observation group were lower than those in the control group,while serum PPARγ SREBP and LXRα levels were higher than those in the control group (P< 0.05);the diagnostic sensitivity and specificity of ABCA 1+ PPARγ+ SREBP+ ADPN + LXRα were higher than those of single detection of ABCA1,PPARγ,SREBP,ADPN and LXRα.Conclusion The levels of ABCA1 and ADPN decreased in patients with type 2 diabetes,while the levels of PPAR γ,SREBP and LXR α was increased.The five joint diagnosis of ABCA1+ PPAR γ+SREBP+ADPN+LXR α has high sensitivity and specificity.It was of important clinical value and worth further application.

Effects of Na+-H+ exchanger 1 knockdown on protein expression levels of ATP binding cassette transporter A1 and cholesterol efflux in hypoxic RAW264.7 cells / 中华老年医学杂志

Objective To explore the effects of Na+ H-exchanger 1(NHE1) knockdown on ATP binding cassette transporter A1 (ABCA1) protein expression levels and cholesterol efflux in the hypoxic RAW264.7 cells.Methods The RAW264.7 cells were infected with lentiviral vectors expressing shRNA specific for NHE1(siNHE1) or scramble RNA (siNC).The expression of NHE1 at mRNA or protein level was detected by qRT-PCR and Western blotting respectively in the infected cells after 24 h in a hypoxia condition.In the meantime,the methods of SNARF-1,Fluo-4 NW andSuc-LLVY-aminoluciferin were employed to determine NHE1 activity,intracellular Ca2+ ([Ca2+]i) and calpain activity,respectively.Furthermore,ABCA1 protein levels were detected by Western blotting in the 24 h hypoxic cells.In parallel,the intracellular cholesterol content and cholesterol efflux were analyzed by the methods of combined enzymatic HLPC and 3 H-cholesterol.Results The hypoxia condition versus the normoxia condition up-regulated NHE1 mRNA and protein expression level and activity by 2.48 folds,1.28 folds and 61.96％ (all P＜0.05),and increased[Ca2+]i and calpain activity by 4.51 folds and 2.41 folds(all P＜0.05).Whereas the NHE1 mRNA and protein expression and activity at the presence of hypoxia were inhibited by siNHE1 with the inhibition ratio of 84.95％,60.75％ and 66.44％,respectively (all P＜0.05)and[Ca2+]i and calpain activity were reduced by 59.23％ and 54.66％ (P＜0.05).Furthermore,the ABCA1 protein level was 61.67％ lower in the hypoxic cells than in the normoxic cells (P＜0.05),and siNHE1 was increased by 56.52％ after treatment of Hypoxia.Hypoxia elevated intracellular total cholesterol and cholesterol ester by 74.57 ％ and 101.81％ (all P＜0.05).Treatment with siNHE1 in the hypoxia condition can reduce total cholesterol and cholesterol ester by 34.24 ％ 及 49.66 ％ (all P＜0.05).Hypoxia reduced the cholesterol efflux by 34.79％(P＜0.05),which were partially reversed by siNHE1.Conclusions NHE1 might play an important role in hypoxia-induced ABCA1 protein attenuation and reverse cholesterol transport dysfunction through[Ca2+]i/calpain pathway.

Correlation of ATP Binding Cassette Transporter A1 Gene Polymorphisms and Lower Extremity Athero-sclerotic Disease / 中国药师

Objective:To analyze the correlation of single nucleotide polymorphisms ( SNP) of ATP binding cassette transporter A1 gene (ABCA1) and lower extremity atherosclerotic disease (LEAD). Methods: The clinical data and peripheral blood were col-lected from 630 participants (314 LEAD cases and 316 normal controls) in Han population of Minnan. The 9 SNP genotypes in the ABCA1 gene were detected by Sequenom MassArray. Results:Among the 9 SNP genotypes, rs2980083 was rejected because it wasn' t in accordance with Hardy-Weinberg equilibrium. Obvious linkage disequilibrium was found between rs2066714 and rs2066715, rs1800976 and rs2246293, rs2246293 and rs2980083, and rs1800976 and rs2980083(D′>0. 9,r2 >1/3). There were no significant differences (P>0. 05) in 6 haplotypes of ABCA1 gene groups between the LEAD cases and the normal controls. No significant differ-ences (P>0. 05) were found in frequency distribution between the LEAD cases and the normal controls in 8 SNP according to the re-sults of genotype statistics. There was no onset risk of LEAD according to the gene logistic regression analysis. Conclusion:The SNPs of rs10124755, rs2980083, rs1800976, rs4149341, rs2066714, rs2066715, rs2066716, rs2230808 and rs2246293 might not correlate with the susceptibility of LEAD in Han population of Minnan.

Effect of microRNA-152 on cholesterol accumulation in RAW264.7 and identification of its functional tar-get genes / 实用医学杂志

Objective To investigate the effect of miR-152 on ox-LDL induced cholesterol accumulation in RAW264.7 macrophages and to verify its target genes. Methods RAW264.7 macrophages were divided into two groups:miR-152 group and negative control group. Total cholesterol(TC),cholesterol ester(CE)concentra- tion and the ratio of CE/TC were observed in the two group by ox-LDL for 48 h. Furthermore,bioinformatics meth-od,dual luciferase reporter assay,real-time quantitative PCR and Western blot were applied to detect the target gene of miR-152. Results As compared with the control group,the contents of TC,CE and the ratio of CE/TC were increased in the miR-152 group. The mRNA and protein expressions of ABCA1 were significantly lower in miR-152 group. Conclusions MiR-152 could inhibit macrophage foam cell formation through decreasing the expres-sion of ABCA1.

Effect of microRNA-152 on cholesterol accumulation in RAW264.7 and identification of its functional tar-get genes / 实用医学杂志

Objective To investigate the effect of miR-152 on ox-LDL induced cholesterol accumulation in RAW264.7 macrophages and to verify its target genes. Methods RAW264.7 macrophages were divided into two groups:miR-152 group and negative control group. Total cholesterol(TC),cholesterol ester(CE)concentra- tion and the ratio of CE/TC were observed in the two group by ox-LDL for 48 h. Furthermore,bioinformatics meth-od,dual luciferase reporter assay,real-time quantitative PCR and Western blot were applied to detect the target gene of miR-152. Results As compared with the control group,the contents of TC,CE and the ratio of CE/TC were increased in the miR-152 group. The mRNA and protein expressions of ABCA1 were significantly lower in miR-152 group. Conclusions MiR-152 could inhibit macrophage foam cell formation through decreasing the expres-sion of ABCA1.

In vitro effect and mechanistic study of compound E23869 on lipid metabolism / 药学学报

This study was designed to identify inducers of ATP-binding cassette transporter A1(ABCA1) and CD36 and lysosomal integral membrane protein-II analogous-1(CLA-1) and to evaluate the in vitro effect of the active compound on lipid metabolism. Among 20000 compounds screened, E23869 was found as a positive hit using cell-based high throughput screening models. The up-regulating activities of E23869 in ABCA1p-LUC and CLA-1p-LUC HepG2 cells were 196% and 198%, respectively. The EC50 values of E23869 in ABCA1p-LUC and CLA-1p-LUC HepG2 cells were 0.25 μmol·L-1 and 0.66 μmol·L-1, respectively. E23869 significantly upregulated the protein levels of ABCA1, scavenger receptor class B type I (SR-BI)/CLA-1 and ATP-binding cassette transporter G1(ABCG1) in both macrophages RAW264.7 and L02 cells by Western blotting analysis. Foam cell assay showed that E23869 inhibited lipids accumulations in macrophages RAW264.7. Cholesterol efflux assay showed that E23869 induced HDL-mediated cholesterol efflux in macrophages RAW264.7. Moreover, E23869 up-regulated ABCA1, SR-BI/CLA-1 and ABCG1 expressions through activation of PPARα and PPARγ. In addition, E23869 weakly promoted in vitro differentiation of mouse preadipocytes 3T3-L1. In conclusion, E23869 up-regulated ABCA1, SR-BI/CLA-1 and ABCG1 expressions to promote cholesterol efflux, which is a good leading compound for regulation of lipid metabolism.

E17110 promotes reverse cholesterol transport with liver X receptor β agonist activity in vitro

Liver X receptor (LXR) plays an important role in reverse cholesterol transport (RCT), and activation of LXR could reduce atherosclerosis. In the present study we used a cell-based screening method to identify new potential LXRβ agonists. A novel benzofuran-2-carboxylate derivative was identified with LXRβ agonist activity: E17110 showed a significant activation effect on LXRβ with an EC50 value of 0.72 μmol/L. E17110 also increased the expression of ATP-binding cassette transporter A1 (ABCA1) and G1 (ABCG1) in RAW264.7 macrophages. Moreover, E17110 significantly reduced cellular lipid accumulation and promoted cholesterol efflux in RAW264.7 macrophages. Interestingly, we found that the key amino acids in the LXRβ ligand-binding domain had distinct interactions with E17110 as compared to TO901317. These results suggest that E17110 was identified as a novel compound with LXRβ agonist activity in vitro via screening, and could be developed as a potential anti-atherosclerotic lead compound.

Effect of combined mulberry leaf and fruit extract on liver and skin cholesterol transporters in high fat diet-induced obese mice

Obesity is an epidemic disease characterized by an increased inflammatory state and chronic oxidative stress with high levels of pro-inflammatory cytokines and lipid peroxidation. Moreover, obesity alters cholesterol metabolism with increases in low-density lipoprotein (LDL) cholesterols and triglycerides and decreases in high-density lipoprotein (HDL) cholesterols. It has been shown that mulberry leaf and fruit ameliorated hyperglycemic and hyperlipidemic conditions in obese and diabetic subjects. We hypothesized that supplementation with mulberry leaf combined with mulberry fruit (MLFE) ameliorate cholesterol transfer proteins accompanied by reduction of oxidative stress in the high fat diet induced obesity. Mice were fed control diet (CON) or high fat diet (HF) for 9 weeks. After obesity was induced, the mice were administered either the HF or the HF with combination of equal amount of mulberry leaf and fruit extract (MLFE) at 500mg/kg/day by gavage for 12 weeks. MLFE treatment ameliorated HF induced oxidative stress demonstrated by 4-hydroxynonenal (4-HNE) and modulated the expression of 2 key proteins involved in cholesterol transfer such as scavenger receptor class B type 1 (SR-B1) and ATP-binding cassette transporter A1 (ABCA1) in the HF treated animals. This effect was mainly noted in liver tissue rather than in cutaneous tissue. Collectively, this study demonstrated that MLFE treatment has beneficial effects on the modulation of high fat diet-induced oxidative stress and on the regulation of cholesterol transporters. These results suggest that MLFE might be a beneficial substance for conventional therapies to treat obesity and its complications.

The study of hydrogen sulfide up-regulates the expression of ABCA1 and promotes the cholesterol efflux in foam cells / 重庆医学

Objective To investigate the effect of hydrogen sulfide (H2S) on the cholesterol efflux and ATP-binding cassette transporter A1 (ABCA1) expression in foam cells .Methods RAW 264 .7 macrophages were incubated with oxidized low density lipoprotein to induce foam cells .Foam cells were incubated with H2S donor sodium hydrosulfide .Cholesterol efflux from macropha-ges was tested by labed cholesterol .The cellular levels of free cholesterol (FC) ,cholesterol ester (CE) and total cholesterol (TC) were measured by high performance liquid chromatography assays .The mRNA and protein expressions of ABCA1 were detected by Real-time PCR and Western blot .Results Compared with the foam cells ,the rates of cholesterol efflux were significantly in-creased ,the levels of TC ,FC ,CE and CE/TC ratio were significantly decreased(P<0 .05) and expression of ABCA1 was signifi-cantly increased by treatment with H2S in dose-and time-dependent manner(P<0 .05) .Conclusion H2S up-regulates of expres-sion ABCA1 and promotes cholesterol efflux in RAW 264 .7 macrophage-derived foam cells .

Correlations of ABCA1 with foam cells formation in renal interstitium, tubulointerstitial lesion and serum cholesterol / 中华肾脏病杂志

Objective To investigate the correlations of ATP-binding cassette transporter A1 (ABCA1) protein expression in renal interstitium with foam cells formation,tubulointerstitial lesion and serum cholesterol in glomerulonephropathy.Methods Five patients with Alport syndrome,28 patients with membranous proliferative glomerular nephritis (MPGN),35 patients with focal segmental glomerulosclerosis (FSGS),36 patients with idiopathic membranous nephropathy (IMN) and 34 patients with IgA nephropathy (IgAN) were enrolled in the study.Expression of ABCA1 protein was detected by immunohistochemical method.The relative area of foam cells in renal interstitium was semi-quantified and the correlations of ABCA1 protein expression in renal interstitium (except for renal tubules) with the relative area of foam cells,integration of tubulointerstitial lesion (TIL) and serum cholesterol were examined using t test and linear correlation analysis.Results In renal interstitium,monocyte-macrophages,foam cells and renal tubular epithelial cells expressed ABCA1 protein.ABCA1 protein expression in renal interstitium with foam cells infiltration was significantly higher as compared to that without foam cells infiltration (P＜ 0.05),but there was no correlation between ABCA1 expression and foam cells area (P＞0.05).In MPGN,FSGS,IMN patients,there was a positive correlation between ABCA1 protein expression in renal interstitium and integration of TIL (P＜0.05).There was a positive correlation between serum cholesterol level and ABCA1 protein expression in renal interstitium (P＜0.05).Conclusions In glomerulonephropathy,cholesterol may promote the ABCA1 expression in renal interstitium.ABCA1 may have double-effects on transportation of cholesterol.ABCA1 may take part in the process of tubulointerstitial lesion.

A Possible Mechanism Linking Hyperglycemia and Reduced High-density Lipoprotein Cholesterol Levels in Diabetes / 华中科技大学学报（医学）（英德文版）

This study investigated the role of glucose in the biogenesis of high-density lipoprotein cholesterol(HDL-C).Mouse primary peritoneal macrophages were harvested and maintained in Dulbecco's modified Eagle's medium(DMEM)containing glucose of various concentrations.The cells were divided into 3 groups in terms of different glucose concentrations in the cultures:Control group (5.6 mmol/L glucose),high glucose concentration groups(16.7 mmol/L and 30 mmol/L glucose).ATP-bindmg cassette transporter A1(ABCA1)mRNA expression in the macrophages was detected by semi-quantitative RT-PCR 24,48 and 72 h after glucose treatment.The results showed that ABCA1 mRNA expression in the 16.7 mmol/L glucose group was not significantly different from that in the control group at all testing time points(P＞0.05 for each).In the 30 mmol/L glucose group,macrophage ABCA1 mRNA expression was not changed significantly at 24 h(P=0.14),but was substantially decreased by 40.4% at 48 h(P=0.009)and by 48.1% at 72 h(P=0.015)as compared with that in the control group.It was concluded that ABCA1 is of vital importance for HDL-C biogenesis.High glucose may hamper HDL-C biogenesis by decreasing ABCA1 expression,which contributes to low HDL-C level in diabetes.

Signal transduction mechanism of Chlamydia pneumoniae in down-regulating the expression of ABCA1 and ABCG1 from THP-1-derived macrophages / 中国病理生理杂志

AIM: To investigate the signal transduction mechanism of Chlamydia pneumoniae (Cpn) in down-regulating the expression of ATP binding cassette A1 (ABCA1) and ATP binding cassette G1 (ABCG1),the key molecules in cholesterol efflux and atherogenesis,from THP-1-derived macrophages. METHODS: Cpn was propagated in Hep-2 cells. THP-1 monocytes were induced into macrophages by 160 nmol/L phorbol myristate acetate (PMA) for 48 h,and were randomly allocated into 4 groups to incubate continually: control group,50 mg/L low density lipoprotein (LDL); Cpn infection group,Cpn (1×10~6 IFU) and 50 mg/L LDL; Cpn and SP600125 (a special JNK inhibiter) group,THP-1 macrophages were previously treated with different concentrations (1-20 μmol/L) of SP600125 for 1 h,and then infected with Cpn (1×10~6 IFU) and 50 mg/L LDL; SP600125 group,SP600125(20 μmol/L)and 50 mg/L LDL. The expressions of ABCA1/ABCG1 and peroxisome proliferator-activated receptor γ (PPARγ) from each group were detected then. The cholesterol efflux was detected by enzyme-fluorescence. The expressions of ABCA1/ABCG1 and PPARγ mRNA and protein were determined by RT-PCR and Western blotting,respectively. RESULTS: Cpn not only down-regulated the ABCA1/ABCG1 expression,but also down-regulated the expression of PPARγ,which regulated the ABCA1/ABCG1 genes transcriptions. However,the mentioned effects of Cpn infection were restrained by the special JNK inhibitor SP600125 in a dose-dependent manner. CONCLUSION: Chlamydia pneumoniae may down-regulate ABCA1/ABCG1 expression from THP-1-derived macrophages via JNK-PPARγ signal transduction pathway.

Influence of ATP-binding cassette transporter A1 protein in eukaryocyte and its expression on arsenic resistance / 中国地方病学杂志

Objective To examine the expression of ATP-binding cassette transporter A1(ABCA1)in eukaryotie cells and the effect of arsenic resistance after the transfection of eukaryotic expression vector containing ABCA1 gene.Methods HeLa cells were transfected with the recombinant plasmid by lipofectaonmine 2000 (recombinant plasmid group),empty plasmid and untransfected HeLa cell as the control group.The level of the mRNA was examined by real-time PCR,and the expression of ABCA1 protein wag examined by Western blot,the change of cell survival rate was examined by methyl thiazolyl tetrazolium(MTT)after exposure in a series of arsenic [0(contro1),4,8,16,32,64,128 μmol/L]for 48 hours.Results Expression level of ABCA1 mRNA in recombinant plasmid,empty plasmid and untransfeeted groups was(2.09±0.08)×10-4,(0.09±0.02)×10-4,(0.08±0.02)×10-4,there was a significant difference between the groups(F=1499.23,P<0.01).The level of ABCA1 mRNA in recombinant plasmid group was higher than empty plasmid and untransfected group(all P<0.01).Western blot showed that specific protein straps existed at 254×103 in all the three groups,with a similar size to the ABCA1 protein.The amount of the recombinant plasmid group was higher than the other two groups.MTT shows that arsenic concentration at 4,8,16,32,64,128 μmol/L,the survival rates of recombinant plasmid group was(94.8±0.9)%,(86.5 ± 2.6)%, (77.8 ± 2.0)%, (56.0 ± 2.0)%, (23.8 ± 1.7)%, (18.6 ± 0.6)%, higher than that of empty plasmid group[ (85.3 ± 1.1)%, (78.7 ± 0.6)%, (67.8 ± 2.4)%, (43.2 ± 1.5)%, (14.5 ± 1.3)%, (8.0 ± 0.4)%], the difference of survival rate had a statistical signifieance(t = 18.985,6.689,5.922,9.504,9.481,32.634, all P < 0.01). Conclusions ABCA1 protein is over expressed in HeLa cells after transfect ABCA1 gene. ABCA1 protein increases resistance of arsenic in HeLa cells.

Effects of berberine on cholesterol efflux in THP-1 macrophage derived foam cells / 上海交通大学学报（医学版）

Objective To investigate the effects of berberine on cholesterol efflux in THP-1 macrophage derived foam cells, and explore the possible mechanism. Methods HP-1 cells were induced into macrophages by phorbol myristate acetate (PMA), and were treated with acetylated low-density lipoprotein (Ac-LDL) to establish the THP-1 macrophage derived foam cell models. Foam cells were divided into blank control group and berberine (5 to 20 μmol/L) treatment groups according to the way of treatment and berberine concentrations. After treatment for 24 h, flow cytometry was employed to detect AcLDL aggregation, enzymic method was adopted to detect contents of cholesterol and triglyceride, scintillation counting technique was used to detect cholesterol efflux, and effects of peroxisome proliferator-activated receptor-γ (PPARγ) antagonist GW9662 pretreatment on cholesterol efflux (pioglitazone as positive control) were analysed. Besides, RT-PCR was applied to detect expression of liver X receptor α (LXRα) and ATP binding cassette transporter A1 (ABCA1) mRNA. ResultsCompared with blank control group, AcLDL aggregation and contents of cholesterol and triglyceride of foam cells in various berberine treatment groups decreased significantly (P＜0.01), while cholesterol efflux increased (P＜0.01) in a dose-dependent manner. After GW9662 pretreatment, there was no significant difference in cholesterol efflux between various berberine treatment groups and control group (P>0.05). Furthermore, expression of LXRα and ABCA1 mRNA of foam cells in various berberine treatment groups was higher than that in blank control group. Conclusion Berberine may increase cholesterol efflux in THP-1 macrophage derived foam cells, the mechanism of which may be associated with activation of PPARγ pathway and increase of expression of LXRα and ABCA1 mRNA.