In this study, we studied the effect of liver X receptor (LXR) agonist T0901317 on Niemann-Pick C1 protein (NPC1) expression in apoE-/- mice. Male apoE-/- mice were randomized into 4 groups, baseline group (n=10), con...In this study, we studied the effect of liver X receptor (LXR) agonist T0901317 on Niemann-Pick C1 protein (NPC1) expression in apoE-/- mice. Male apoE-/- mice were randomized into 4 groups, baseline group (n=10), control group (n=14), treatment group (n=14) and prevention group (n=14). All of the mice were fed with a high-fat/high-cholesterol (HFHC) diet containing 15% fat and 0.25% cholesterol. The baseline group treated with vehicle was sacrificed after 8 weeks of the diet. The control group and the prevention group were treated with either vehicle or T0901317 daily by oral gavage for 14 weeks. The treatment group was treated with vehicle for 8 weeks, and then was treated with the agonist T0901317 for additional 6 weeks. Gene and protein expression was analyzed by real-time quantitative PCR, immunohistochemistry and Western blotting, respectively. Plasma lipid concentrations were measured by commercially enzymatic methods. We used RNA interference technology to silence NPC1 gene expression in THP-1 macrophage-derived foam cells and then detected the effect of LXR agonist T0901317 on cholesterol efflux. Plasma triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and apoA-I concentrations were markedly increased in T0901317-treated groups. T0901317 treatment reduced the aortic atherosclerotic lesion area by 64.2% in the prevention group and 58.3% in the treatment group. LXR agonist treatment increased NPC1 mRNA expression and protein levels in the small intestine, liver and aorta of apoE-/- mice. Compared with the normal cells, cholesterol efflux of siRNA THP-1 macrophage-derived foam cells was significantly decreased, whereas cholesterol efflux of LXR agonist T0901317-treated THP-1 macrophage-derived foam cells was significantly increased. Our results suggest that LXR agonist T0901317 inhibits atherosclerosis development in apoE-/- mice, which is related to up-regulating NPC1 expression.展开更多
非酒精性脂肪性肝炎(Non-alcoholic steatohepatitis,NASH),又称代谢性脂肪性肝炎,是病理变化与酒精性肝炎相似但无过量饮酒史的临床综合征,好发于中年特别是超重肥胖个体。非酒精性脂肪性肝炎与肥胖、胰岛素抵抗、2型糖尿病、高脂血症...非酒精性脂肪性肝炎(Non-alcoholic steatohepatitis,NASH),又称代谢性脂肪性肝炎,是病理变化与酒精性肝炎相似但无过量饮酒史的临床综合征,好发于中年特别是超重肥胖个体。非酒精性脂肪性肝炎与肥胖、胰岛素抵抗、2型糖尿病、高脂血症等代谢紊乱关系密切,主要特征为肝细胞大泡性脂肪变伴肝细胞损伤和炎症,严重者可发展为肝硬化,但至今NASH尚无得到批准的治疗方案。在寻找有效的治疗方法时,解决代谢失调、炎症和抗纤维化的新策略不断涌现。法尼类X受体(Farnesoid X receptor,FXR)除了是胆汁酸代谢和肠肝循环的关键调节剂外,还参与调节代谢稳态,使其成为NASH中有吸引力的治疗靶点。本文综述了FXR激动剂对NASH治疗的研究进展。展开更多
肝X受体(liver X receptors,LXRs)是孤儿核受体转录因子超家族成员,当LXRs被激活后,可调节靶基因的转录表达,不但参与胆固醇、脂肪、糖的代谢以及炎症等过程,并且在许多恶性肿瘤组织中均有表达。为全面了解肝X受体激动剂在治疗癌症中的...肝X受体(liver X receptors,LXRs)是孤儿核受体转录因子超家族成员,当LXRs被激活后,可调节靶基因的转录表达,不但参与胆固醇、脂肪、糖的代谢以及炎症等过程,并且在许多恶性肿瘤组织中均有表达。为全面了解肝X受体激动剂在治疗癌症中的研究现状,本文将从肝X受体激动剂与胃癌、肝癌、卵巢癌、乳腺癌、子宫内膜癌、肺癌以及结直肠癌的相关性方面进行综述。展开更多
Nuclear receptor transcription factors are ligand-activated proteins that control various biological events from cell growth and development to lipid metabolism, and energy and glucose homeostasis. Nuclear receptors a...Nuclear receptor transcription factors are ligand-activated proteins that control various biological events from cell growth and development to lipid metabolism, and energy and glucose homeostasis. Nuclear receptors are important drug targets for metabolic diseases. Liver X receptors (LXRs) are nuclear receptor transcription factors that play essential roles in regulation of cholesterol, triglyceride, fatty acid, and glucose homeostasis. LXR-deficient mice have shown the association of LXR-signaling pathway dysfunction with several human pathologies including atherosclerosis, hyperlipidemia, Alzheimer s disease and cancer. Thus, LXRs are promising pharmacological targets for these diseases. Synthetic LXR agonists may lower cholesterol, but increase triglyceride and induce fatty liver. The naturally occurring LXR ligands, with moderate activity, may serve as nutraceuticals for prevention or treatment of the disorders, while minimizing potential side effects. In this review, recent advances in natural LXR modulators are summarized including agonist, antagonist and the modulator of LXR pathway.展开更多
Nogo-B受体(Nogo-B receptor,NgBR)参与脂肪肝和胰岛素敏感性的形成,但是并不清楚肝X受体(liver X receptor,LXR)激动剂是否能够调控NgBR的表达。文章使用人工合成的LXR激动剂(T0901317和GW3965)分析其对肝源细胞系中NgBR表达的影响,构...Nogo-B受体(Nogo-B receptor,NgBR)参与脂肪肝和胰岛素敏感性的形成,但是并不清楚肝X受体(liver X receptor,LXR)激动剂是否能够调控NgBR的表达。文章使用人工合成的LXR激动剂(T0901317和GW3965)分析其对肝源细胞系中NgBR表达的影响,构建正常或突变NgBR启动子,通过双荧光素酶报告基因系统检测LXR激动剂对启动子活性的影响;采用CRISPR-CAS9方法建立LXRα或LXRβ基因敲除的HepG2细胞系,通过Western Blot检测相关基因的表达变化;向ApoE-/-小鼠腹腔注射LXR激动剂T0901317,分析小鼠肝脏中NgBR的表达变化。结果发现,LXR激动剂能够通过激活LXR促进NgBR蛋白的表达,该诱导作用是以LXRE依赖的方式进行的,并且LXR的表达发挥着重要作用。在体内实验中,也证明了LXR激动剂T0901317上调NgBR蛋白表达。结果表明,NgBR是LXR的靶蛋白,LXR通过结合NgBR启动子LXRE序列促进其转录和翻译。展开更多
基金the National Natural Science Foundation of China (Grant No. 30470720)Hunan Provincial Natural Sciences Foundation of China (Grant No. 06jj5058)
文摘In this study, we studied the effect of liver X receptor (LXR) agonist T0901317 on Niemann-Pick C1 protein (NPC1) expression in apoE-/- mice. Male apoE-/- mice were randomized into 4 groups, baseline group (n=10), control group (n=14), treatment group (n=14) and prevention group (n=14). All of the mice were fed with a high-fat/high-cholesterol (HFHC) diet containing 15% fat and 0.25% cholesterol. The baseline group treated with vehicle was sacrificed after 8 weeks of the diet. The control group and the prevention group were treated with either vehicle or T0901317 daily by oral gavage for 14 weeks. The treatment group was treated with vehicle for 8 weeks, and then was treated with the agonist T0901317 for additional 6 weeks. Gene and protein expression was analyzed by real-time quantitative PCR, immunohistochemistry and Western blotting, respectively. Plasma lipid concentrations were measured by commercially enzymatic methods. We used RNA interference technology to silence NPC1 gene expression in THP-1 macrophage-derived foam cells and then detected the effect of LXR agonist T0901317 on cholesterol efflux. Plasma triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and apoA-I concentrations were markedly increased in T0901317-treated groups. T0901317 treatment reduced the aortic atherosclerotic lesion area by 64.2% in the prevention group and 58.3% in the treatment group. LXR agonist treatment increased NPC1 mRNA expression and protein levels in the small intestine, liver and aorta of apoE-/- mice. Compared with the normal cells, cholesterol efflux of siRNA THP-1 macrophage-derived foam cells was significantly decreased, whereas cholesterol efflux of LXR agonist T0901317-treated THP-1 macrophage-derived foam cells was significantly increased. Our results suggest that LXR agonist T0901317 inhibits atherosclerosis development in apoE-/- mice, which is related to up-regulating NPC1 expression.
文摘非酒精性脂肪性肝炎(Non-alcoholic steatohepatitis,NASH),又称代谢性脂肪性肝炎,是病理变化与酒精性肝炎相似但无过量饮酒史的临床综合征,好发于中年特别是超重肥胖个体。非酒精性脂肪性肝炎与肥胖、胰岛素抵抗、2型糖尿病、高脂血症等代谢紊乱关系密切,主要特征为肝细胞大泡性脂肪变伴肝细胞损伤和炎症,严重者可发展为肝硬化,但至今NASH尚无得到批准的治疗方案。在寻找有效的治疗方法时,解决代谢失调、炎症和抗纤维化的新策略不断涌现。法尼类X受体(Farnesoid X receptor,FXR)除了是胆汁酸代谢和肠肝循环的关键调节剂外,还参与调节代谢稳态,使其成为NASH中有吸引力的治疗靶点。本文综述了FXR激动剂对NASH治疗的研究进展。
文摘肝X受体(liver X receptors,LXRs)是孤儿核受体转录因子超家族成员,当LXRs被激活后,可调节靶基因的转录表达,不但参与胆固醇、脂肪、糖的代谢以及炎症等过程,并且在许多恶性肿瘤组织中均有表达。为全面了解肝X受体激动剂在治疗癌症中的研究现状,本文将从肝X受体激动剂与胃癌、肝癌、卵巢癌、乳腺癌、子宫内膜癌、肺癌以及结直肠癌的相关性方面进行综述。
文摘Nuclear receptor transcription factors are ligand-activated proteins that control various biological events from cell growth and development to lipid metabolism, and energy and glucose homeostasis. Nuclear receptors are important drug targets for metabolic diseases. Liver X receptors (LXRs) are nuclear receptor transcription factors that play essential roles in regulation of cholesterol, triglyceride, fatty acid, and glucose homeostasis. LXR-deficient mice have shown the association of LXR-signaling pathway dysfunction with several human pathologies including atherosclerosis, hyperlipidemia, Alzheimer s disease and cancer. Thus, LXRs are promising pharmacological targets for these diseases. Synthetic LXR agonists may lower cholesterol, but increase triglyceride and induce fatty liver. The naturally occurring LXR ligands, with moderate activity, may serve as nutraceuticals for prevention or treatment of the disorders, while minimizing potential side effects. In this review, recent advances in natural LXR modulators are summarized including agonist, antagonist and the modulator of LXR pathway.
文摘Nogo-B受体(Nogo-B receptor,NgBR)参与脂肪肝和胰岛素敏感性的形成,但是并不清楚肝X受体(liver X receptor,LXR)激动剂是否能够调控NgBR的表达。文章使用人工合成的LXR激动剂(T0901317和GW3965)分析其对肝源细胞系中NgBR表达的影响,构建正常或突变NgBR启动子,通过双荧光素酶报告基因系统检测LXR激动剂对启动子活性的影响;采用CRISPR-CAS9方法建立LXRα或LXRβ基因敲除的HepG2细胞系,通过Western Blot检测相关基因的表达变化;向ApoE-/-小鼠腹腔注射LXR激动剂T0901317,分析小鼠肝脏中NgBR的表达变化。结果发现,LXR激动剂能够通过激活LXR促进NgBR蛋白的表达,该诱导作用是以LXRE依赖的方式进行的,并且LXR的表达发挥着重要作用。在体内实验中,也证明了LXR激动剂T0901317上调NgBR蛋白表达。结果表明,NgBR是LXR的靶蛋白,LXR通过结合NgBR启动子LXRE序列促进其转录和翻译。