二氢杨梅素经激活SIRT1-AMPK通路抑制高脂饮食诱导的肥胖小鼠肝脏脂质沉积

目的探究二氢杨梅素(dihydromyricetin,DHM)对高脂饮食诱导的肥胖小鼠肝脏脂质蓄积的作用及其机制。方法C57BL/6J小鼠60只,随机分为6组(n=10):①ND组:正常饲料;②ND+L-DHM组:正常饲料+低剂量DHM(125 mg·kg^-1·d^-1);③ND+H-DHM组:正常饲料+高剂量DHM(250 mg·kg^-1·d^-1);④HFD组:高脂饲料;⑤HFD+L-DHM组:高脂饲料+低剂量DHM;⑥HFD+H-DHM组:高脂饲料+高剂量DHM。记录小鼠体重;16周后,测空腹血脂;计算体脂重量;肝脏HE和油红O染色;荧光定量PCR和Western blot检测肝脏SIRT1、AMPK、ACC、FAS、SREBP-1和PPARα、CPT1的表达。结果与ND组相比,HFD组小鼠体重、体脂、血清TG、TC、HDL水平明显增加;肝脏内脂肪蓄积增加,肝脏SREBP-1c、FAS、ACC1表达增加,而PPARα、CPT1、SIRT1和AMPK表达下降。经DHM处理后,HFD小鼠上述指标发生逆转;但ND小鼠上述指标无明显改变。结论DHM可能通过激活SIRT1-AMPK通路抑制脂质合成,促进脂质分解,改善高脂饮食诱导的肥胖小鼠肝脏脂质沉积。     

microRNA let-7a在刀豆蛋白A诱导的小鼠肝损伤中的作用

目的:探讨microRNA let-7a对刀豆蛋白A(Concanavalin A,ConA)小鼠肝损伤的保护作用.方法:建立ConA诱导的小鼠肝损伤模型,采用尾静脉注射let-7a慢病毒表达质粒的方法,并在造模前7d给予let-7a进行治疗干预.采用自动生化仪分析检测血清ALT变化;ELISA检测血清TNF-α、IL-6和干扰素-γ(IFN-γ)表达水平;HE染色肝脏组织病理学观察,评价let-7a治疗效果.结果:治疗组血清ALT水平较模型组明显降低(P＜0.01);与模型组相比,治疗组IL-6水平明显降低(P＜0.01),治疗组血清炎症细胞因子TNF-α、IFN-γ水平也显著下降(P＜0.05).肝脏组织病理学检查显示,治疗组较模型组肝组织损伤程度明显减轻,炎症细胞明显减少(P＜0.01,P＜0.05).治疗组小鼠生存率明显高于模型组(P＜0.01).结论:let-7a对ConA诱导的小鼠肝损伤有保护作用,该作用可能通过抑制相关炎症细胞因子TNF-α、IL-6和IFN-γ表达来实现.     

荷叶碱防治小鼠高脂血症作用及其机制

目的研究荷叶碱对饮食诱导的高脂血症小鼠的影响并了解其降脂机制。方法将小鼠根据饲料分为3组:正常对照组(n=10)、模型对照组(n=10)、干预组(n=10)。正常对照组采取普通饮食(ANI-76A饲料:12.4%脂肪,68.8%碳水化合物,18.8%蛋白质);模型对照组采用高脂饮食诱导(高脂饲料:37.1%脂肪,42.4%碳水化合物,20.5%蛋白质);干预组在高脂饲料基础上添加了0.5%荷叶碱。小鼠自由食用,共10周。比较3组小鼠体质量、血脂、脂代谢关键酶、肝脏氧化应激的变化并研究脂质代谢通路。结果高脂饮食成功诱导出高脂血症模型小鼠:肥胖、血脂增高(P<0.05)。干预组与模型对照组比较:小鼠体质量降低[(33.97±3.46)g比(27.62±2.87)g],血脂降低[(2.73±0.26)g比(1.91±0.21)g],均P<0.05,但不能改善其高甘油三酯血症(P>0.05);肝脂酶活性[(4.15±1.26)U·m L-1比(9.01±1.34)U·m L-1]及脂蛋白脂酶活性提高[(8.12±3.07)U·m L-1比(13.48±3.75)U·m L-1],且降低了肝脏氧化应激(P<0.05)。高脂饮食诱导脂质合成基因SREBP-1c、FAS、SCD-1及PPARγmRNA显著上调(P<0.05),而使脂质氧化代谢基因PPARα、CPT-1a mRNA下调(P<0.05),干预组则逆转了这些变化(P<0.05)。结论荷叶碱能改善小鼠高脂血症,且可能与增加脂酶活性、减少氧化应激及调控脂质合成与氧化代谢相关。     

PPARγ在肝细胞癌组织中的表达及临床意义

目的 探讨过氧化物酶体增殖物活化受体γ( PPARγ)在肝细胞癌(HCC)中表达的临床意义.方法 半定量RT-PCR法、免疫组织化学法检测34例患者HCC组织及相对应的癌旁组织的PPARγ表达,结合临床特征行统计学分析.结果 79.4% (27/34)HCC组织PPARγ mRNA表达高于癌旁组织.PPARγ蛋白在HCC组织中均呈阳性表达,表达在胞浆和(或)胞核中;而癌旁组织为阴性或弱阳性表达,为胞浆染色.阳性表达分级之间存在显著差异,χ2=39.62,P＜0.05.PPARγ mRNA表达水平与蛋白表达分级与HCC大小、包膜完整、高转移复发倾向和HBV感染及肝硬化背景密切相关(P＜0.05);但与患者年龄、性别、Okuda分期、pTNM分期、组织分化程度、AFP阳性和随访转移结果无关.PPARγ mRNA及蛋白高表达均与患者的总生存期负相关.结论 PPARγ在HCC中过表达,与HCC的发展可能有关,可能作为判断HCC预后的一种预测性指标.     

不同品系小鼠肥胖模型比较及C57BL/6J小鼠肥胖机制研究

目的建立和比较不同品系小鼠肥胖模型,并研究C57BL/6J小鼠肥胖形成的分子机制。方法选用C57BL/6J、ICR和KM 3个品系♂小鼠,各品系小鼠随机分为正常对照和高脂模型组,分别在饲养4周与8周后测定小鼠体重、脂肪重量、Lee’s指数;脂肪细胞形态学观察和横截面面积计量;酶法检测血脂和LPL活性,应用荧光实时定量PCR技术探讨模型形成分子机制。结果 C57BL/6J小鼠模型组体重、脂肪重量、Lee’s指数、脂肪细胞横截面面积与对照组比较均明显升高,形成良好肥胖模型,而ICR和KM小鼠肥胖指标不如C57BL/6J小鼠变化明显。机制研究表明,C57BL/6J小鼠造模后血清LPL活性升高,肝脏PPARα、脂肪组织PPARγ和DGAT表达上调,脂肪组织HSL、ATGL和TGH表达下调,这些酶、受体的表达变化是形成肥胖的重要机制。结论 C57BL/6J小鼠经高脂饲料诱导4周后可形成良好肥胖模型,PPARα、PPARγ、LPL、DGAT、HSL、ATGL和TGH既是肥胖形成的主要机制,也是减肥药物作用靶点判断的生物标志物。     

PPARγ对RAW264.7小鼠巨噬细胞异质性的影响

目的 探讨PPAR γ对缺氧复氧RAW264.7小鼠巨噬细胞异质性的影响.方法 体外培养小鼠巨噬细胞系(RAW264.7),制备缺氧复氧模型,用慢病毒包装进行PPARγ过表达和基因沉默,细胞分为对照组、模型组、过表达PPARγ组和PPARγ基因沉默组.用ELISA法、RT-PCR、Western印迹法和免疫荧光法检测各组细胞巨噬细胞亚型M1标志物诱导型一氧化氮合酶(iNOS)、M2标志物CD206及肿瘤坏死因子-α(TNF-α)、干扰素-γ(IFN-γ)的表达.结果 与对照组相比,ELISA法检测模型组TNF-α和IFN-γ水平明显升高(均P＜0.01),RT-PCR、Western印迹法和免疫荧光检测均显示TNF-α、IFN-γ、iNOS表达上调,CD206表达下调.与模型组相比,过表达PPARγ显著减轻了IRI导致的TNF-α、IFN-γ和iNOS表达的上调,上调了CD206表达;与此相反,PPARγ基因沉默加重IRI导致TNF-α、IFN-γ和iNOS表达上调,下调了CD206表达.结论 PPARγ在小鼠RAW264.7巨噬细胞缺氧复氧模型中参与调节巨噬细胞表型转换.     

罗格列酮延缓慢性肾病进展的机制研究

目的 探讨过氧化物酶体增殖物激活受体γ(PPARγ)激动药罗格列酮对5/6肾切除肾衰竭大鼠的肾脏保护作用及可能作用机制.方法选用180～200 g健康雄性SD大鼠建立5/6肾切除肾衰竭模型,分为假手术组、模型对照组和罗格列酮组.第12周时采用断头法处死大鼠,并检测各组大鼠血清尿素氮、肌酐及24 h尿蛋白水平;取残余肾组织行病理检查,判断肾小球硬化、肾小管间质损伤程度;采用免疫组化方法观察PPARγ和神经型一氧化氮合酶(nNOS)在肾脏组织的分布;利用RT PCR和Western Blot检测PPARγ和nNOS 蛋白和mRNA的表达水平.结果与假手术组比较,模型对照组和罗格列酮组大鼠24 h尿蛋白、血清尿素氮及肌酐均显著升高(P＜0.01);但与模型对照组比较,罗格列酮组各指标则明显降低(P＜0.05).病理学检查示模型对照组大鼠肾组织有明显的肾小球硬化及肾小管间质损伤,肾小球硬化指数及肾小管间质损伤指数均较假手术组明显增高(P＜0.01);而罗格列酮组上述指标则较模型对照组明显降低(P＜0.05).免疫组化结果显示5/6肾切除大鼠PPARγ主要分布在肾小管上皮细胞、系膜细胞和浸润的巨噬细胞,nNOS主要定位在致密斑,内髓集合管也有表达.模型对照组PPARγ、nNOS蛋白和mRNA的表达较假手术组明显下降(P＜0.05),而罗格列酮组PPARγ和nNOS的表达则较模型对照组明显升高(P＜0.05).结论大鼠5/6肾切除后,给予罗格列酮可以明显减轻肾小球硬化和肾间质纤维化的程度,其作用机制可能与其上调PPARγ和nNOS基因的表达有关,且有明显的相关性.     

人参茎叶皂苷对小鼠脂肪肝的作用及机制研究

目的探讨人参茎叶皂苷对小鼠脂肪肝的作用及机制。方法小鼠分为正常对照组(NC)和模型组。喂高脂饲料复制脂肪肝模型,12 wk后证实造模成功后,模型组小鼠随机分为高脂组(HF);正常饮食治疗组(NT);人参茎叶皂苷小剂量组(GSL1);人参茎叶皂苷大剂量组(GSL2)。除HF组饲高脂饲料外,其余各组饲基础饲料。GSL1组给予GSL50 mg.kg-1.d-1灌胃,GSL2组给予GSL 100 mg.kg-1.d-1灌胃,其余各组以同等容积蒸馏水灌胃。灌胃2wk后处死所有动物,检测血清TC、TG、HDL-C、LDL-C、ALT含量;并观察肝指数和肝组织TC、TG、SOD、MDA含量,肝脏病理形态学改变及氧化物酶体增殖物激活受体α(PPARα)、细胞色素P450 2E1(CYP2E1)的表达。结果GSL2组可以明显降低肝指数、血脂、肝脂和MDA含量,增加SOD活性,改善小鼠肝脏病理形态学改变,增加肝组织PPARαmRNA水平、降低CYP2E1 mRNA水平。NT组脂肪肝有一定的改善作用,但效果不理想;GSL1组各项指标与NT组相比差异无显著性。结论人参茎叶皂苷可能通过增加肝组织PPARαmRNA表达,降低血脂和肝脂水平;并且通过降低CYP2E1 mRNA表达,抑制脂质过氧化反应,发挥治疗脂肪肝的作用。     

高脂饮食致脂肪肝胰岛素抵抗大鼠模型中PPARs的表达及作用

目的研究PPARα、PPARγ在SD大鼠NAFLD/NASH的形成中的作用,并初步从胰岛素抵抗(IR)方面探讨其机制。方法将SD大鼠60只随机分为正常对照组(NC组,n=20)、高脂对照组(FC组,n=20),高脂加罗格列酮组(FR组,n=10)、高脂加非诺贝特组(FF组,n=10)。饲养12周末时随机取NC组与FC组各10只一并做高胰岛素正葡萄糖钳夹实验及肝组织的HE染色,确定造模成功。然后给予罗格列酮、非诺贝特及继续高脂饮食干预,共4周。氨基转移酶、三酰甘油等以生物化学方法测定,并以逆转录-聚合酶链反应(RT-PCR)技术分析PPARα、PPARγ基因的mRNA表达水平。结果 FC组大鼠呈高脂血症,与NC组比较,PPARα的mRNA表达下调,而PPARγmRNA表达上调(P<0.05),IR和肝细胞脂肪变及炎性程度加重(P<0.05);与FC组比较,FF及FR组PPARα的mRNA表达上调,PPARγmRNA表达下调,IR明显改善(P<0.05)。结论在高脂饮食诱导的NASH、IR模型中,PPARα、PPARγ的mRNA表达水平与IR密切相关,可以共同促进NASH的进展,而使用PPARs激动剂后对大鼠NASH及IR起到了有效治疗作用。     

膳食钙对高脂饮食大鼠肥胖形成的影响

目的 研究膳食钙摄入对高脂饮食大鼠肥胖形成的影响.方法 30只SD大鼠标准饲料饲养10d后,随机分为标准饲料(A)组(1.30%钙),高脂饲料(B)组(1.57%钙)和高脂加钙饲料(C)组(2.57%钙),饲养6周后处死,称量各组大鼠体重、体脂,用ELISA法测血清钙调激素甲状旁腺素(PTH)和1,25-(OH)2D3水平,用RT-PCR检测白色脂肪组织(WAT)中Vitmin D受体(VDR)、脂肪酸合成酶(FAS)、解偶联蛋白2(UCP2)基因mRNA表达水平.结果 (1)B组体重、Lee's指数、脂肪湿重显著高于A组和C组(P＜0.05);(2)C组的血清钙调激素水平均显著低于B组(P＜0.05);(3)C组VDR和FAS基因mRNA表达水平均显著低于B组(P＜0.05),C组UCP2基因mRNA表达水平均显著高于B组(P＜0.05).结论 高钙膳食可能通过降低血清钙调节激素水平,影响脂肪代谢和钙代谢,从而减少高脂饮食大鼠体重和脂肪重量的增加.     

Monosodium glutamate neonatal intoxication associated with obesity in adult stage is characterized by chronic inflammation and increased mRNA expression of peroxisome proliferator-activated receptors in mice

The monosodium glutamate (MSG) neonatal administration in mice provides a model of obesity with impaired glucose tolerance (IGT) and insulin resistance. However, the inflammatory profile of cytokines produced from fat tissue and its relationship to the metabolic dysfunction induced by MSG have not yet been revealed. The aim of this study was to establish the inflammatory profile attributed to MSG by measuring the expression of adipokines in visceral fat and serum of 19-week-old mice as well as the peroxisome proliferator-activated receptors alpha and gamma (PPARα and γ). Some metabolic and biochemical parameters were also quantified. The MSG increased mRNA expression of interleukin-6 (IL-6), tumour necrosis factor-alpha (TNFα), resistin and leptin, but adiponectin did not exhibit any changes. In addition, impaired glucose tolerance, increased levels of insulin, resistin and leptin were observed in serum. Both PPARα and PPARγ were activated in MSG-induced obese mice, which might explain its inflammatory profile. However, liver transaminases were severely depressed, indicating that MSG may also induce liver injury, contributing to inflammation. The MSG neonatal neuro-intoxication in mice may thus provide a model of obesity and inflammation characterized by the dual activation of PPARα and PPARγ, which might offer new insights into the mechanism of inflammatory diabetes in obesity leading to steatohepatitis, as well as a suitable model to study the role of new therapeutic agents to prevent or reduce insulin resistance, the inflammatory state and liver steatosis.     

氢杨梅素改善高脂饮食诱导的肥胖小鼠肝脏脂肪沉积及机制（英文）

有文献报道, SIRT1-AMPK信号通路可能在DHM改善肝脏细胞甘油三酯蓄积、胰岛素抵抗等作用中发挥作用。为此,本课题拟进一步观察DHM对高脂饮食诱导的肥胖小鼠肝脏脂肪沉积的影响,并探讨其可能机制。C57BL/6J小鼠采用普通饲料和高脂饲料喂养,同时分别用或不用低剂量(125 mg/kg)或高剂量(250 mg/kg)的DHM处理16周。实验期间,每两周检测体重一次。16周后,眼眶静脉取血并处死动物,同时取肩胛下、附睾与腹股沟的脂肪并用电子秤进行称重,并记录脂肪重量。全自动生化分析仪检测:血清甘油三酯(triglyceride,TG)、血清总胆固醇(totalcholesterol,TC)、血清高密度脂蛋白(high-densitylipoprotein,HDL)、血清低密度脂蛋白(low-densitylipoprotein,LDL)。取肝脏甲醛固定、HE和油红O染色检测肝脏脂肪沉积情况;比色法检测肝脏MDA和SOD含量; Realtime PCR检测相关指标的基因表达:IL-6、IL-8、TNF-α、乙酰辅酶A羧化酶(acetyl-Co A carboxylase, ACC)、固...     

脂肪干细胞来源外泌体携带miR-27抑制白色脂肪的棕色化

目的 探讨脂肪干细胞（ASC）来源的外泌体在白色脂肪棕色化中的作用。方法 分离培养并鉴定小鼠ASC细胞;慢病毒转染构建过表达 miR-27的 ASC细胞;超高速离心提取正常及过表达 miR-27的 ASC细胞分泌的外泌体,实时荧光定量核酸扩增（qRT-PCR）分析外泌体中 miR-27的表达量;高脂喂食构建肥胖小鼠模型,分别注射过表达 miR-27外泌体（过表达组）、正常 ASC外泌体（正常表达组）及生理盐水（对照组）,在寒冷暴露条件下监测体质量变化;剥离小鼠附睾皮下脂肪组织和肩胛骨脂肪组织,比较组织大小,蛋白免疫印迹法（Western blot）检测解偶联蛋白 1（UCP1）、过氧化物酶体增殖剂激活受体 γ（PPARγ）、含 PR结构域的锌指蛋白 16（PRDM16）、过氧化物酶体增殖子激活受体 γ共激活因子 1α（PGC-1α）的表达。结果 成功提取 ASC及其外泌体,并成功转染 miR-27;ASC及其外泌体中的 miR-27显著高于白色脂肪组织（P＜0.05）。与对照组相比,过表达组及正常表达组的小鼠体质量下降幅度小,随时间的增加效果更加明显（P＜0.05）。过表达组及正常表达组的小鼠的附睾皮下脂肪组织较对照组的小鼠要稍大;而肩胛骨脂肪组织的大小无明显变化。正常表达组与过表达组的 UCP1、PPARγ、PRDM16及 PGC-1α的表达水平较对照组下降（P＜0.05）。结论 脂肪干细胞来源外泌体能够抑制白色脂肪细胞的棕色化。     

富含生育三烯酚的棕榈油对动脉粥样硬化小鼠糖代谢的影响

目的探讨富含生育三烯酚的棕榈油(TRF)对动脉粥样硬化小鼠糖代谢的影响及其可能的作用机制。方法载脂蛋白E基因缺陷(ApoE-/-)小鼠分为模型对照组、TRF0.05%和0.2%(W/W)组。TRF均匀混于饲料中,各组饲料中添加10%(W/W)的脂肪和0.2%(W/W)的胆固醇诱导动脉粥样硬化的形成。小鼠经TRF处理12和14周后分别进行口服葡萄糖耐量实验(OGTT)和胰岛素耐量实验(ITT);用相应试剂盒检测血清中总胆固醇(TC)、甘油三酯(TG)、游离脂肪酸(FFA)和胰岛素的含量;实时荧光定量PCR分析白色脂肪组织(WAT)中过氧化物酶体增殖物激活受体γ(PPARγ)、脂联素和葡萄糖转运体4(Glut4)的mRNA水平;利用荧光素酶报告系统检测TRF对PPRAγ的激活作用。结果OGTT和ITT实验显示,在非禁食和禁食的情况下,TRF均能够降低ApoE-/-小鼠的血糖,改善胰岛素的敏感性;TRF组小鼠血清中TG和FFA的水平均低于模型对照组;在WAT中,与模型对照组相比,TRF0.2%组上调脂联素mRNA水平(1.73±0.32)倍,TRF0.05%和0.2%组分别增加Glut4mRNA水平(1.89±0.24)和(2.01±0.61)倍,PPARγmRNA水平没有改变。荧光素酶报告系统检测结果显示,TRF对PPARγ-配体结合结构域、PPARγ1和PPARγ2的激活作用分别是溶剂对照组的(2.7±0.2),(6.1±0.6)和(5.3±0.1)倍。结论TRF能够很好地改善动脉粥样硬化小鼠的糖代谢,TRF发挥这些作用的部分原因是通过激活PPARγ来实现的。     

Dietary corosolic acid ameliorates obesity and hepatic steatosis in KK-Ay mice

Corosolic acid (CRA), a constituent of Banaba leaves, has been reported to exert anti-hypertension, anti-hyperinsulinemia, anti-hyperglycemia, and anti-hyperlipidemia effects as well as to induce anti-inflammatory and anti-oxidative activities. The aim of this study was to investigate the inhibitory effects of CRA on the development of obesity and hepatic steatosis in KK-Ay mice, a genetically obese mouse model. Six-week-old KK-Ay mice were fed a high fat diet for 9 weeks with or without 0.023% CRA. Nine-week CRA treatment resulted in 10% lower body weight and 15% lower total fat (visceral plus subcutaneous fat) mass than in control mice. CRA treatment reduced fasting plasma levels of glucose, insulin, and triglyceride by 23%, 41%, and 22%, respectively. The improved insulin sensitivity in CRA-treated mice may be due on part to the increased plasma adiponectin and white adipose tissue (WAT) AdipoR1 levels. In addition, CRA treatment increased the expression of peroxisome proliferator-activated receptor (PPAR) alpha in liver and PPAR gamma in WAT. This is the first study to show that CRA treatment can contribute to reduced body weight and amelioration of hepatic steatosis in mice fed a high fat diet, due in part to increased expression of PPAR alpha in liver and PPAR gamma in WAT.     

Effect of oxymatrine on lipid metabolism regulated genes in liver of fat-induced insulin resistance in ApoE-/-mice北大核心CSCD

Aim To investigate the effect of oxymatrine on lipid metabolism regulated genes in liver in fat-induced insulin resistance in ApoE-/- mice. Methods Seventeen C57BL/6J male mice were selected in normal control group. Sixty-eight ApoE-/- mice with high fat diet for 16 weeks, were randomly divided into model group, oxymatrine low, middle and high dose groups. Then they were gavaged for 8 weeks. Body weight and general biochemical indicators were determined in mice. The mRNA and protein expression levels of LPL, FAT/CD36, CPT1, UCP2, SREBP-1 c, FAS and ACC were examined by real-time PCR and Western blot in the liver. Results Compared with model group, oxymatrine reduced body weight (BW) , fasting blood glucose (FBG), cholesterol (TC) , triglyceride (TG) , free fatty acids (FFA), fasting plasma insulin (FINS) and insulin resistance index(HOMA-IR) (P < 0. 05) , while improved glucose infusion rate (GIR) . Oxymatrine down-regulated the mRNA and protein expression of LPL, FAT/CD36, UCP2, SREBP-1c, FAS and ACC(P <0. 05) ,and up-regulated the mRNA and protein expression of CPT1 in varying degrees (P < 0. 05). Conclusion Oxymatrine can regulate the expression of lipid metabolism regulated genes in liver and improve insulin resistance in ApoE-/- mice induced by high fat diet.     

Synthesis, characterization and biological evaluation of ureidofibrate-like derivatives endowed with peroxisome proliferator-activated receptor activity

A series of ureidofibrate-like derivatives was prepared and assayed for their PPAR functional activity. A calorimetric approach was used to characterize PPARγ-ligand interactions, and docking experiments and X-ray studies were performed to explain the observed potency and efficacy. R-1 and S-1 were selected to evaluate several aspects of their biological activity. In an adipogenic assay, both enantiomers increased the expression of PPARγ target genes and promoted the differentiation of 3T3-L1 fibroblasts to adipocytes. In vivo administration of these compounds to insulin resistant C57Bl/6J mice fed a high fat diet reduced visceral fat content and body weight. Examination of different metabolic parameters showed that R-1 and S-1 are insulin sensitizers. Notably, they also enhanced the expression of hepatic PPARα target genes indicating that their in vivo effects stemmed from an activation of both PPARα and γ. Finally, the capability of R-1 and S-1 to inhibit cellular proliferation in colon cancer cell lines was also evaluated.     

白藜芦醇对大鼠酒精性脂肪肝的保护作用

目的 研究白藜芦醇对酒精性脂肪肝模型大鼠肝脏的保肝作用.方法 用白酒ig诱导建立大鼠酒精性脂肪肝(AFL)模型,分设空白对照组、模型组、硫普罗宁组(阳性对照)、白藜芦醇高、中、低剂量(250、125、62.5 mg· kg-)治疗组,测定血清中过氧化物酶体增殖物激活受体γ(PPARγ)、肝组织中肿瘤坏死因子(TNF-α)与层黏连蛋白(LN)在大鼠酒精性脂肪肝中的变化.结果 与模型组比较,白藜芦醇治疗组大鼠血清中PPARγ浓度升高,而TNF-α、LN含量显著降低(P＜0.05).结论 白藜芦醇能提高血清中PPARγ的浓度,降低肝组织中TNF-α与LN的含量,保护肝细胞,改善酒精诱导的酒精性脂肪肝.     

Flavonoid-enriched extract from Hippophae rhamnoides seed reduces high fat diet induced obesity,hypertriglyceridemia, and hepatic triglyceride accumulation in C57BL/6 mice

Context: Flavonoid-enriched extract from Hippophae rhamnoides L. (Elaeagnaceae) seed (FSH) has shown beneficial effects in anti-hypertension and lowering cholesterol level. However, evidence for its efficacy in treating obesity is limited.

Objective: We sought to determine if FSH can reduce body weight and regulate lipid metabolism disorder in high fat diet (HFD)-induced obese mouse model, and to investigate potential molecular targets involved.

Materials and methods: C57BL/6 mice were fed with HFD for 8 weeks to induce obesity. The modeled mice were divided into four groups and treated with vehicle, rosiglitazone (2?mg/kg), low (100?mg/kg) and high (300?mg/kg) dose of FSH, respectively. Normal control was also used. The treatments were administered orally for 9 weeks. We measured the effect of FSH on regulating body weight, various liver and serum parameters, and molecular targets that are key to lipid metabolism.

Results: FSH administration at 100 and 300?mg/kg significantly reduced body weight gain by 33.06 and 43.51%, respectively. Additionally, triglyceride concentration in serum and liver were decreased by 15.67 and 49.56%, individually, after FSH (300?mg/kg) treatment. Upon FSH (100 and 300?mg/kg) treatment, PPARα mRNA expression was upregulated in liver (1.24- and 1.42-fold) and in adipose tissue (1.66- and 1.72-fold). Furthermore, FSH downregulated PPARγ protein level both in liver and adipose tissue. Moreover, FSH inhibited macrophage infiltration into adipose tissues, and downregulated TNFα mRNA expression in adipose tissue (38.01–47.70%).

Conclusion: This effect was mediated via regulation of PPARγ and PPARα gene expression, and suppression of adipose tissue inflammation.