核受体因子PPARγ的研究进展

过氧化物酶体增殖剂激活受体γ(PPARγ)是核激素受体超家族成员.PPARγ具有多种生物学效应,对机体起重要作用,是目前的研究热点.本文对PPARγ的结构、作用机理以及生物学作用等进行了综述.     

猪PPARs基因组织表达特性的研究

以成年母猪为研究材料,采用RT-PCR半定量法对猪PPARα、β/δ和γ基因组织表达特点进行了研究。结果表明:在检测的18种组织中除胰腺组织外,3种PPAR亚型在其他17种组织中均有表达。表达量高低依次为PPARα,子宫绒毛膜>皮下脂肪>卵巢>大肠>脾脏>大脑>肾上腺>心脏>肺>小肠>脊髓>子宫蜕膜>胃>肝脏>背最长肌>膀胱>肾脏;PPARδ,子宫绒毛膜>卵巢>大肠>脾脏>肝脏>胃>皮下脂肪>大脑>肺>肾上腺>子宫蜕膜>脊髓>背最长肌>心脏>肾脏>小肠>膀胱;PPARγ,背最长肌>皮下脂肪>卵巢>脾脏>肺>大肠>膀胱>子宫绒毛膜>子宫蜕膜>心脏>胃>肝脏>肾脏>大脑>脊髓>肾上腺>小肠。3种亚型PPAR在卵巢和/或子宫绒毛膜中都有较高的表达,提示它们与猪的繁殖性能相关。     

过氧化物酶体增殖剂受体与脂质代谢调控

综述了过氧化物酶体增殖剂受体在动物体内的分布、结构与转录调节机制及其对脂肪细胞分化、脂质代谢的调控。     

过氧化物酶体增殖物激活受体对鱼类代谢的调节作用北大核心

过氧化物酶体增殖物激活受体(PPARs)是核激素受体家族中的配体激活受体,在糖脂代谢、细胞分化、胚胎发育、脂肪生成等过程中发挥重要作用。文章概述鱼类PPARs基因的克隆与表达,阐述了PPARs在鱼类糖脂代谢和能量代谢中的作用,旨为PPARs调节鱼类的糖脂代谢作用机制提供参考。     

过氧化物酶体增殖剂激活受体研究进展

随着人们生活水平的提高,对畜禽的肉质提出了更高要求。因此,改善肉质就成为育种工作者的主要任务之一。适量的皮下脂肪可改善胴体外观,但皮下脂肪和腹脂太多则不好,而较高含量的肌内脂肪(I MF)则能改善肉品质。近几年来,畜禽脂肪性状相关基因的研究已成为动物遗传育种研究的热     

畜产动物过氧化物酶体增殖物激活受体基因的表达模式及功能研究进展

过氧化物酶体增殖物激活受体(PPARs)是一类配体依赖的核转录因子,属核受体超家族成员。自从PPARs于1990年被发现以来,研究人员对啮齿动物和人体PPARs基因的结构与多态性、组织中表达模式、影响表达的因素、信号传导途径以及调控脂类代谢等方面的功能进行了广泛和深入的研究。近年来,PPARs基因在畜禽及鱼类中的表达模式及功能的研究也逐渐开展起来,并取得了一些进展。本文对PPARs基因在畜产动物组织中的表达模式及功能研究进行了综述。     

过氧化物酶体增殖物激活受体(PPARs)在细胞及整个生物水平的多方面作用

代谢综合征是多种代谢性疾病的总称,包括肥胖、血脂异常、葡糖耐受不良、炎症和高血压.近年许多研究表明,PPAR可以改善这类代谢异常情况.PPARs是细胞核激素受体超家族配体激活转录因子,分为PPARα、PPARβ/δ、PPARγ三个亚型,分布在各不同组织,功能涵盖广泛.     

过氧化物酶体增殖物激活受体γ信号通路调控脂质代谢的研究进展

过氧化物酶体增殖物激活受体γ(PPARγ)是体内脂肪形成的必需转录因子,处于脂质沉积过程中信号传递通路的核心枢纽位置,促进多能间充质干细胞向脂肪细胞的定向、增殖分化和脂质沉积。本文首先介绍了PPARγ的基本结构和调控靶基因的基本特征,然后以脂肪细胞形成和脂肪沉积为主线,综述了PPARγ信号通路在脂肪细胞形成、脂肪沉积和脂肪因子分泌、营养水平等脂肪代谢过程的调控作用,最后对PPARγ与生物钟相互反馈调节关系以及其在脂质沉积中扮演重要作用进行了概述,对进一步深入综合了解PPARγ对脂肪代谢调控的分子机制具有重要意义,为脂肪代谢及相关疾病的人工干预提供靶基因和新途径。     

两种PPARs调控剂对草鱼生长和血液生化指标的影响

过氧化物酶体增殖物激活受体(peroxisome proliferator-activated receptors,PPARs)是配体激活的转录因子核受体超家族成员之一,目前已知有三种亚型:PPARα、PPARβ和PPARγ。PPARs与各自特异性配体结合而激活后,与维甲酸类受体X(retinoid X receptor,RXR)或糖皮质激素受体形成     

睾丸注射法制备携带徐淮山羊过氧化氢酶体激活增殖受体γ基因转基因羊的研究

为探究睾丸注射法制备转基因动物的可能性,将携带有徐淮山羊过氧化氢酶体激活增殖受体γ(PPARγ)和绿色荧光蛋白标签的重组载体经脂质体包裹后,将线性化的重组质粒pEGFP-PPARγ通过随机打点注射入性成熟的湖羊睾丸内,采用常规PCR、基因组DNA点杂交及蛋白免疫印迹技术检测外源PPARγ基因在湖羊体内稳定整合的能力,并检测F1代阳性个体屠宰性能、肌内脂肪含量、器官重量及肉品质。F1代羔羊检测转基因羊阳性率为13.7%,证实外源基因在转基因后代体内成功表达。阳性个体胴体重和屠宰率极显著低于对照组个体(P<0.01),阳性个体骨肉比极显著高于对照组个体(P<0.01);阳性个体背最长肌脂肪含量显著高于对照组个体(P<0.05),腰肌内脂肪含量与股二头肌内脂肪含量差异不显著(P>0.05);阳性个体肺脏和小肠极显著大于对照组个体(P<0.01),阳性个体脾脏显著大于对照组个体(P<0.05),阳性个体心脏和肺脏显著小于对照组个体(P<0.05),肝脏、肾脏、胃、睾丸、皮、头之间差异不显著(P>0.05);阳性个体股二头肌嫩度显著低于对照组个体(P<0.05),pH、肉色、失水率之间差异不显著(P>0.05)。     

Avian Atherosclerosis: Parrots and Beyond

Atherosclerotic lesions are prevalent in companion psittacine species. Parrots account for much of the veterinary scientific information on avian atherosclerosis, but the lesions have been described in virtually all avian orders. This review presents a synthesis of the epidemiologic, clinical, diagnostic, and therapeutic information known in psittaciformes, at this time, which may help in the veterinary management of atherosclerotic diseases. The article further expands on nondomestic avian species for which information is restricted to pathologic and prevalence studies. A thorough knowledge of atherosclerosis is of the upmost importance for avian clinicians as the disease is common, affects most species of birds, and seems to be associated with captive lifestyles characterized by decreased activity and nonnative diets. Therefore, avian veterinarians are expected to be largely exposed to this chronic medical condition through patient presentation and should be prepared to properly manage this disease.     

重组脂联素对皖南花猪脂肪细胞脂联素及其受体mRNA表达的影响

脂联素（Adp）是主要由脂肪组织分泌的细胞因子,有重要的生理作用。本试验旨在研究重组脂联素（rAdp）对皖南花猪脂肪细胞脂联素及其受体2,AMP激活蛋白激酶（AMPK）、过氧化物增殖剂活化受体α（PPARα）mR-NA表达的影响。选择10d皖南花猪皮下脂肪组织分离前体脂肪细胞,增殖培养至80%融合后换分化培养基培养,细胞分化后用0、2和10mg/L rAdp分别处理12和48h。油红O染色法鉴定脂肪细胞,MTT方法检测细胞活力;酶法测定培养液中甘油释放量,荧光定量RT-PCR方法检测脂肪细胞脂联素（Adp）、脂联素受体1（AdpR1）、脂联素受体2（AdpR2）、PPARα和AMPK mRNA表达。结果显示,rAdp处理后,脂肪细胞活力总体有降低趋势,10mg/L处理48h达到显著水平（P〈0.05）;rAdp处理对甘油释放的抑制作用未达到差异水平。rAdp处理12h后,脂肪细胞AdpR1和AdpR2mRNA表达显著升高（P〈0.01）,但无剂量依赖性;rAdp处理48h后,脂肪细胞AdpmRNA表达显著下降（P〈0.05）。rAdp处理12h后,脂肪细胞PPARαmRNA表达显著升高（P〈0.01）,且有剂量效应性;而AMP AMPK mRNA表达均无显著性变化。结果提示,重组脂联素处理猪原代脂肪细胞有降低细胞活力和抑制脂肪细胞甘油释放量的趋势,能显著上调AdpR1、AdpR2和PPARα基因的表达,从而刺激脂肪酸氧化和甘油三酯的水解作用。     

广西巴马小型猪动脉粥样硬化模型的制作

本试验旨在制作广西巴马小型猪动脉粥样硬化模型,初步判断猪发生动脉粥样硬化时的指数值,以期为今后建立相关模型提供依据。试验选取广西巴马小型猪试验组和对照组各10头,通过饲喂高脂高胆固醇饲料建立动脉粥样硬化模型,检测建模过程中血液生化指标,将动脉粥样硬化指数与血管切片作关联分析,初步拟定发生动脉粥样硬化时的指数值。屠宰后血管切片结果显示,试验组有2头广西巴马小型猪发生动脉粥样硬化,对照组均正常。2头广西巴马小型猪的血管切片结果与动脉粥样硬化指数进行关联分析后,初步拟定的动脉粥样硬化指数值在3.8以上,并持续3个月以上。     

Preparation of Atherosclerosis Model Using Guangxi Bama Mini-pig

The atherosclerosis (AS) model was prepared in Guangxi Bama mini-pig,and the atherosclerosis index (AI) was preliminarily identified in occurrence of AS to provide the basis for the preparation of related models.20 Guangxi Bama mini-pigs were randomly divided into control group and experimental group which were fed with high fat and cholesterol diet to prepare the AS model.Blood biochemical indexes were detected in the process of model preparation and the correlation between AI and the results of vascular slices was analyzed to initially draw up AI of AS.The results of vascular slices showed that the incidence rates of AS of Guangxi Bama mini-pigs in experimental group and control group were 20% and 0,respectively.The association analysis between the results of vascular slices and AI in the pathogenic Guangxi Bama mini-pigs preliminarily suggested that AI was above 3.8 and lasted for more than 3 months during the attack.     

Atherosclerosis: Comparative Pathogenesis,Lipoprotein Metabolism,and Avian and Exotic Companion Mammal Models

Atherosclerosis is a chronic inflammatory disease of the arterial wall where the accumulation of foam cells, lipids, calcium, and cellular debris leads to large fibrofatty atheromatous plaques narrowing the arterial lumen. As the principal cause of human deaths in the world, the pathogenesis of atherosclerosis has been extensively studied, as well as lipid and lipoprotein metabolism, across species. Important aspects of the disease were first investigated experimentally in a wide array of animal models, including laboratory avian and mammalian species also kept as companion pets. Although the disease is primarily a significant clinical entity in avian patients, the wealth of information obtained from companion exotic mammals is of interest to understand the complex comparative pathogenesis of atherosclerotic lesions. This review presents the current concepts of atherogenesis and lipoprotein metabolism followed by a brief overview of species peculiarities as it relates to the experimental reproduction of the disease. This overview should provide interesting insight on atherosclerosis, which spontaneously or experimentally affects many zoological companion species commonly seen by veterinarians.     

利维爱(Livial)对去势雌兔动脉粥样硬化影响的病理学观察

以去势雌兔作为雌激素缺乏模型，研究了利维爱(Livial)对食饵性兔动脉粥样硬化的斑块及血管病理形态学变化的影响。将30只7～9月龄、体质量约4kg的新西兰大白兔随机分为3组：A组为去势后饲喂高胆固醇组，B组为假手术后饲喂高胆固醇组。C为去势后饲喂高胆固醇并补充利维爱组。饲养12周后处死。测定胸主动脉AS斑块的面积。在光镜和电镜下观察血管壁的病理组织学变化。结果：假手术组和利维爱组硬化斑块面积均小于A组，利维爱组斑块面积与A、B组比较差异显著；假手术组和利维爱组血管的病理变化比A组轻。利维爱组血管的形态学结构接近正常血管，病理变化最轻。由此认为，利维爱对防治动脉粥样硬化的形成和发展有较好的效果。     

兔动脉粥样硬化斑块与肾素-血管紧张素系统关系的研究

为探讨肾素 -血管紧张素系统 ( RAS)对实验性兔动脉粥样硬化 ( AS)的影响 ,采用 2 0只雄性新西兰大白兔 ,随机分为 2组。对照组饲以全价颗粒饲料 ,实验组采用高胆固醇饮食( HCD)饲喂法建立 AS模型。分别检测总胆固醇( TC)、血管紧张素转换酶 ( ACE)和血管紧张素 ( Ang ) ,并对主动脉 AS病灶进行病理检查。结果表明 :与对照组相比 ,高胆固醇饮食 1周后 TC开始显著升高 ,第 4周达高峰 ,第 1 6周组织中 Ang 水平显著升高 ( P <0 .0 5) ;病理检查见主动脉内膜满布淡黄色斑块 ,镜检由增厚的内膜、泡沫细胞和胆固醇结晶组成 ;对照组无异常。高胆固醇饮食 1 6周可建立兔 AS模型 ,RAS可影响 AS斑块的形成     

Effect of dietary fish oil on the expression of genes involved in lipid metabolism in liver and skeletal muscle of lactating sows

This study investigated the hypothesis that dietary supplementation of fish oil as a source of n‐3 polyunsaturated fatty acids (PUFA) influences the expression of target genes of sterol regulatory element‐binding proteins (SREBP)‐1 and (SREBP)‐2 involved in triacylglycerol (TAG) synthesis and fatty acid and cholesterol metabolism in the liver, and moreover activates the expression of target genes of peroxisome proliferation‐activated receptor (PPAR)‐α involved in TAG and fatty acid catabolism in liver and skeletal muscle. Twenty lactating sows were fed a control diet or a fish oil diet with either 50 g of a mixture of palm oil and soya bean oil (4:1, w/w) or fish oil per kg. The diet of the fish oil group contained 19.1 g of n‐3 PUFA (mainly 20:5 n‐3 and 22:6 n‐3) per 100 g of total fatty acids, while the diet of the control group contained 2.4 g of n‐3 PUFA (mainly 18:3 n‐3) per 100 g of total fatty acids. The fish oil group had reduced relative mRNA concentrations of various target genes of SREBP‐1 involved in fatty acid and TAG synthesis in comparison with the control group (p < 0.05). Relative mRNA concentrations of target genes of PPARα involved in fatty acid catabolism in both liver and muscle, and mRNA concentrations of target genes of SREBP‐2 involved in cholesterol synthesis and uptake were not influenced by fish oil supplementation. Concentrations of cholesterol and TAG in plasma, fat content of milk and weight gains of litters during the suckling period were not different between the two groups of sows. In conclusion, this study suggests that fish oil has only minor effects on hepatic lipid metabolism, which are non‐critical with respect to milk production in sows.     

Dietary Considerations for Atherosclerosis in Common Companion Avian Species

Atherosclerosis is a disease that occurs in many avian species commonly presented to veterinarians. Many risk factors for atherosclerosis are well defined in mammals but not in avian species. Dietary nutrients can play a large role in reducing the severity and prevalence of atherosclerosis in both avian and mammalian species. Information on the effect of dietary nutrients on atherosclerosis in Falconiformes and other birds of prey is extremely limited as no studies were identified by the authors. Dietary cholesterol can be fed to induce the development of atherosclerosis in avian species that consume nonanimal protein. Diets containing high levels of omega-3 fatty acids reduce the prevalence and severity of atherosclerosis, with fish oil being more effective than α-linolenic acid. The presence of dietary cholesterol results in higher levels of dietary protein, increasing the prevalence and severity of atherosclerosis, but if dietary cholesterol is absent, there is a subsequent decrease in atherosclerosis. Pectin in the diet decreased the occurrence of atherosclerosis but also decreased the availability of nutrients owing to faster ingesta passage rates. Feed restriction has also been found to decrease the prevalence of atherosclerosis in birds. It should be noted that many studies have found nutrient interaction effects on the development of atherosclerosis, with some being “neutralizing” or negative, so caution should be observed when manipulating avian diets. The objective of this article is to review the effects of dietary nutrients on atherosclerosis.