Objective To study the effect of retinoid X receptor alpha (RXRα) transfection plus treatment with the RXRα ligand, 9-cis-RA, on the proliferation and phenotype of platelet-derived growth factor (PDGF)-activated hep...Objective To study the effect of retinoid X receptor alpha (RXRα) transfection plus treatment with the RXRα ligand, 9-cis-RA, on the proliferation and phenotype of platelet-derived growth factor (PDGF)-activated hepatic stellate cells (HSCs). Methods PDGF activated rat hepatic stellate cells were transfected with eukaryotic expression vector pcDNA3.1- human RXRα, and confirmed by Western blot. Proliferation of transfected HSC was assayed by bromodeoxyuridine (BrdU) incorporation as well as MTT, and the phenotype (α-smooth muscle actin, desmin) was observed by immunocytochemistry with image analysis. Results Transfection of the RXRα gene and treatment with ligand 9-cis-RA of PDGF-activated HSCs extended the increased expression of RXRα protein for at least 168 hours. Cell proliferation and expressions of alpha-smooth muscle actin (α-SMA) and desmin were blocked, compared with groups of sham-transfected, PDGF-activated, no transfection, no ligand treatment, and irrelevant ligand treated HSCs. Conclusion Transfection with the RXRα gene followed by 9-cis-RA ligand treatment will inhibit the proliferation and reverse the phenotype of activated HSC.展开更多
大黄素(emodin)对多种肿瘤细胞有较强的抑制增殖和诱导凋亡的作用,但其作用机制尚不清楚。本研究通过配体-受体竞争结合实验以及报告基因检测了大黄素对维甲酸X受体(retinoid X receptor alpha,RXRα)的结合和转录活性的调控,并研究了...大黄素(emodin)对多种肿瘤细胞有较强的抑制增殖和诱导凋亡的作用,但其作用机制尚不清楚。本研究通过配体-受体竞争结合实验以及报告基因检测了大黄素对维甲酸X受体(retinoid X receptor alpha,RXRα)的结合和转录活性的调控,并研究了大黄素对肺癌细胞H460和肝癌细胞SMMC-7721生长和凋亡的作用。结果发现,大黄素对两种癌细胞有很强的抑制增殖作用,加入RXRα的天然配体9-顺式视黄酸(9-cis-retinoid acid,9-cis-RA)共同处理可显著缓解这种抑制作用。大黄素能浓度依赖地引起两种癌细胞系的凋亡,使细胞核出现碎裂和染色质浓染。报告基因实验发现大黄素对RXRα同源和异源二聚体的转录激活有显著抑制作用。体外的配体竞争结合实验发现,大黄素不直接结合RXRα的配体结合区。蛋白质免疫印迹实验发现,大黄素不影响RXRα的蛋白表达。结果提示,大黄素具有诱导肺癌细胞H460和肝癌细胞SMMC-7721凋亡和抑制细胞生长的作用,大黄素抑制9-cis-RA对RXR转录激活作用以及9-cis-RA具有一定程度拮抗大黄素对肺癌细胞H460和肝癌细胞SMMC-7721的生长抑制作用,提示大黄素的抗癌作用可能与细胞内RXR的功能有关,并以RXR转录非依赖性的方式起作用。配体竞争结合实验结果提示大黄素可能间接作用于RXR。展开更多
目的:通过视黄醇类核内受体-α(retinoid X receptor-alpha,RXR-α)基因慢病毒表达载体的构建,及其对肝星状细胞(hepatic stellate cells,HSC)活化、增殖影响的研究,探讨RXR-α基因在肝纤维化中的作用。方法:①构建RXR-α基因慢病毒表...目的:通过视黄醇类核内受体-α(retinoid X receptor-alpha,RXR-α)基因慢病毒表达载体的构建,及其对肝星状细胞(hepatic stellate cells,HSC)活化、增殖影响的研究,探讨RXR-α基因在肝纤维化中的作用。方法:①构建RXR-α基因慢病毒表达载体;②分离和体外培养大鼠HSC;③将自发活化的HSC分成3组,即正常对照组、阴性对照组和RXR-α载体组;分别将空白慢病毒载体和RXR-α慢病毒载体转染自体活化的HSC,采用Western印迹法检测各组细胞中RXR-α、α-SMA和Ⅰ型胶原蛋白表达变化,用MTT法检测各组HSC培养24、48、72及96 h后的增殖情况。结果:正常对照组及阴性对照组HSC中几乎没有RXR-α蛋白的表达,而RXR-α载体转染组的HSC中出现RXR-α蛋白的明显表达。与正常对照组及阴性对照组相比,RXR-α载体组转染的HSC中α-SMA蛋白表达量显著下降(t=3.767,P<0.01和t=8.491,P<0.05),Ⅰ型胶原蛋白表达也显著降低(t分别为10.449和10.756,P值均<0.01),同时HSC的增殖能力也显著下降(t分别为4.381和1.778,P值均<0.05)。而阴性对照组与正常对照组相比,α-SMA和Ⅰ型胶原蛋白表达量和HSC增殖能力无明显变化(P>0.05)。结论:RXR-α基因在HSC内的增强表达能显著抑制HSC的活化和增殖,具有潜在的抑制肝纤维化的作用。展开更多
OBJECTIVE:To investigate the therapeutic mechanism of compound Yindan decoction (CYD) in a rat model of acute intrahepatic cholestatic (AIC).METHODS:A total of 108 adult male rats were randomly divided into control (n...OBJECTIVE:To investigate the therapeutic mechanism of compound Yindan decoction (CYD) in a rat model of acute intrahepatic cholestatic (AIC).METHODS:A total of 108 adult male rats were randomly divided into control (n =18) and AIC groups (n =90).AIC was induced in rats using alpha-naphthylisothiocyanate (ANIT)(75 mg/kg,10 mL/kg in corn oil,p.o.).Then,90 AIC rats were randomly divided into five groups:a control group (n =18),a CYD high dose group (n =18),a CYD middle dose group (n =18),a CYD low dose group (n =18),and a ursodeoxycholicacid (UDCA) group (n =18).According to sampling time,each group was subdivided into three subgroups:24 h (n =6),48 h (n =6),and 72 h groups (n =6).The CYD-high,-middle and-low groups were orally administered 24.48,12.24,and 6.12 g.kg-1.d-1 modified CYD,respectively,while the model group was given 20 mL/kg of body weight of distilled water once a day.The UDCA group was given 67.5 mg.kg-1.d-1 UDCA once a day.Radioimmunity assay was used to detect the activity of alanine aminotransferase (ALT),aspartate aminotransferase (AST),alkaline phosphatase (ALP),gamma-glutamyl transpeptidase (GGT) and the levels of total bilirubin (TBil) and indirectbiliruin (DBil) in rats.Reverse transcription quantitative polymerase chain reaction (qRT-PCR),Western blot analysis,and immunohistochemistry were used to detect multidrug resistance-associated protein 2 (MRP2) expression.In vitro,HepG2 hepatocellular carcinoma cells were treated with CYD medicated serum at a concentration of 15 mol/L.MRP2 and retinoid X receptor alpha (RXRα) expression was analyzed by qRT-PCR and Western blotting.RESULTS:Serum levels of ALT,AST,GGT,ALP,TBil,and DBil were significantly reduced in the CYD and positive drug groups compared with the control group (P < 0.05 and P < 0.01,respectively).Pathological changes in rat liver tissues at 72 h in the CYD-high and-medium dose groups and positive drug group were not significant compared with the control group.CYD and UDCA treatment ameliorated ANIT-induced biliary epithelial cell proliferation.Neutrophil infiltration was rare and little focal necrosis was observed in Iobules in the CYD-high and-medium dose groups and UDCA group at 72 h.Compared with the control group,the expression of MRP2 mRNA and MRP2 protein in the liver tissue of the CYD groups was significantly increased (P <0.05 and P < 0.01,respectively).MRP2 expression and RXRα nuclear receptor mRNA and protein levels in the CYD groups were significantly increased compared with the control and UDCA groups (P <0.01).CONCLUSION:CYD can alleviate cholestasis in ANIT-induced AIC rats,and the mechanism underlying this action might involve increases in ALT,AST,GGT,ALP,TBil,and DBil and upregulation of MRP2 and RXRα mRNA and protein levels.展开更多
基金theNationalNaturalScienceFoundationofChina (No 39970 337)
文摘Objective To study the effect of retinoid X receptor alpha (RXRα) transfection plus treatment with the RXRα ligand, 9-cis-RA, on the proliferation and phenotype of platelet-derived growth factor (PDGF)-activated hepatic stellate cells (HSCs). Methods PDGF activated rat hepatic stellate cells were transfected with eukaryotic expression vector pcDNA3.1- human RXRα, and confirmed by Western blot. Proliferation of transfected HSC was assayed by bromodeoxyuridine (BrdU) incorporation as well as MTT, and the phenotype (α-smooth muscle actin, desmin) was observed by immunocytochemistry with image analysis. Results Transfection of the RXRα gene and treatment with ligand 9-cis-RA of PDGF-activated HSCs extended the increased expression of RXRα protein for at least 168 hours. Cell proliferation and expressions of alpha-smooth muscle actin (α-SMA) and desmin were blocked, compared with groups of sham-transfected, PDGF-activated, no transfection, no ligand treatment, and irrelevant ligand treated HSCs. Conclusion Transfection with the RXRα gene followed by 9-cis-RA ligand treatment will inhibit the proliferation and reverse the phenotype of activated HSC.
文摘大黄素(emodin)对多种肿瘤细胞有较强的抑制增殖和诱导凋亡的作用,但其作用机制尚不清楚。本研究通过配体-受体竞争结合实验以及报告基因检测了大黄素对维甲酸X受体(retinoid X receptor alpha,RXRα)的结合和转录活性的调控,并研究了大黄素对肺癌细胞H460和肝癌细胞SMMC-7721生长和凋亡的作用。结果发现,大黄素对两种癌细胞有很强的抑制增殖作用,加入RXRα的天然配体9-顺式视黄酸(9-cis-retinoid acid,9-cis-RA)共同处理可显著缓解这种抑制作用。大黄素能浓度依赖地引起两种癌细胞系的凋亡,使细胞核出现碎裂和染色质浓染。报告基因实验发现大黄素对RXRα同源和异源二聚体的转录激活有显著抑制作用。体外的配体竞争结合实验发现,大黄素不直接结合RXRα的配体结合区。蛋白质免疫印迹实验发现,大黄素不影响RXRα的蛋白表达。结果提示,大黄素具有诱导肺癌细胞H460和肝癌细胞SMMC-7721凋亡和抑制细胞生长的作用,大黄素抑制9-cis-RA对RXR转录激活作用以及9-cis-RA具有一定程度拮抗大黄素对肺癌细胞H460和肝癌细胞SMMC-7721的生长抑制作用,提示大黄素的抗癌作用可能与细胞内RXR的功能有关,并以RXR转录非依赖性的方式起作用。配体竞争结合实验结果提示大黄素可能间接作用于RXR。
基金Supported by National Natural Science Foundation of China:Research on the mechanism of clearing away damp and heat and cooling and activating blood method based on the transcriptional regulation signaling pathway of hepatic membrane transport protein for the treatment of acute intrahepatic cholestasis(No.81573897)
文摘OBJECTIVE:To investigate the therapeutic mechanism of compound Yindan decoction (CYD) in a rat model of acute intrahepatic cholestatic (AIC).METHODS:A total of 108 adult male rats were randomly divided into control (n =18) and AIC groups (n =90).AIC was induced in rats using alpha-naphthylisothiocyanate (ANIT)(75 mg/kg,10 mL/kg in corn oil,p.o.).Then,90 AIC rats were randomly divided into five groups:a control group (n =18),a CYD high dose group (n =18),a CYD middle dose group (n =18),a CYD low dose group (n =18),and a ursodeoxycholicacid (UDCA) group (n =18).According to sampling time,each group was subdivided into three subgroups:24 h (n =6),48 h (n =6),and 72 h groups (n =6).The CYD-high,-middle and-low groups were orally administered 24.48,12.24,and 6.12 g.kg-1.d-1 modified CYD,respectively,while the model group was given 20 mL/kg of body weight of distilled water once a day.The UDCA group was given 67.5 mg.kg-1.d-1 UDCA once a day.Radioimmunity assay was used to detect the activity of alanine aminotransferase (ALT),aspartate aminotransferase (AST),alkaline phosphatase (ALP),gamma-glutamyl transpeptidase (GGT) and the levels of total bilirubin (TBil) and indirectbiliruin (DBil) in rats.Reverse transcription quantitative polymerase chain reaction (qRT-PCR),Western blot analysis,and immunohistochemistry were used to detect multidrug resistance-associated protein 2 (MRP2) expression.In vitro,HepG2 hepatocellular carcinoma cells were treated with CYD medicated serum at a concentration of 15 mol/L.MRP2 and retinoid X receptor alpha (RXRα) expression was analyzed by qRT-PCR and Western blotting.RESULTS:Serum levels of ALT,AST,GGT,ALP,TBil,and DBil were significantly reduced in the CYD and positive drug groups compared with the control group (P < 0.05 and P < 0.01,respectively).Pathological changes in rat liver tissues at 72 h in the CYD-high and-medium dose groups and positive drug group were not significant compared with the control group.CYD and UDCA treatment ameliorated ANIT-induced biliary epithelial cell proliferation.Neutrophil infiltration was rare and little focal necrosis was observed in Iobules in the CYD-high and-medium dose groups and UDCA group at 72 h.Compared with the control group,the expression of MRP2 mRNA and MRP2 protein in the liver tissue of the CYD groups was significantly increased (P <0.05 and P < 0.01,respectively).MRP2 expression and RXRα nuclear receptor mRNA and protein levels in the CYD groups were significantly increased compared with the control and UDCA groups (P <0.01).CONCLUSION:CYD can alleviate cholestasis in ANIT-induced AIC rats,and the mechanism underlying this action might involve increases in ALT,AST,GGT,ALP,TBil,and DBil and upregulation of MRP2 and RXRα mRNA and protein levels.
