脂联素受体表达的调节机制

脂联素是一种脂肪细胞分泌的蛋白因子,在人和动物体内通过其受体的介导来发挥多种生理功能,尤以增敏胰岛素、调节糖代谢和脂代谢、保护内皮细胞和对抗炎症等作用重大.本文就脂联素受体1和2的结构和分布、影响它们表达的因素及其机制的进行了综述.     

脂联素与其受体的结构及在脂类代谢中的作用机制

脂联素（AdipoQ）是一种主要由脂肪组织分泌的内源性细胞因子,在调节脂类代谢中发挥重要作用。AdipoQ首先与其受体[脂联素受体1(AdipoRl)和脂联素受体2(AdipoR2)]位于膜外的C端结合,再通过AdipoQ受体N端与信号接头蛋白结合,进而激活下游腺苷酸活化蛋白激酶（AMPK）与过氧化物酶体增殖物激活受体α(PPARα)等多条信号通路,促进脂肪酸氧化,抑制脂质合成,从而调节脂类代谢。本文就AdipoQ及其受体的结构、信号接头蛋白和AdipoQ对动物脂质代谢的调节机制进行综述。     

脂联素及其受体激动剂在禽脂肪性肝病中的应用展望

脂联素(adiponectin)是一种能参与调控糖和脂质代谢、能量调节、免疫反应以及抵抗炎症、氧化应激和细胞凋亡等多种生理过程的激素。禽脂肪性肝病是由于禽肝脏中脂肪酸合成与酯化、脂肪酸转运、脂肪酸氧化、脂肪分解和利用等代谢途径发生异常, 导致的脂类代谢紊乱、肝细胞脂肪变性和炎症反应。文章介绍了脂联素及其分子结构, 脂联素受体及其参与的信号通路, 并重点阐述了脂联素对肝脏脂质代谢、炎症、氧化应激、肝细胞凋亡与自噬方面的调节作用及机制, 以及脂联素受体激动剂的生理作用。同时, 结合禽脂肪性肝病的发生发展机制, 对脂联素及其受体激动剂的应用前景进行了展望。文章为预防和治疗禽类乃至其他动物的脂肪性肝病提供了新的思路。     

脂联素及其受体对脂代谢信号转导通路的调控机制

脂联素(Adipo Q)是一种由脂肪组织分泌的细胞因子,在调节畜禽的脂代谢等方面具有重要作用。Adipo Q主要通过与脂联素受体1(Adipo R1)和脂联素受体2(Adipo R2)2种受体结合来调控腺苷酸活化蛋白激酶α(AMPKα)、p38丝裂原激活蛋白激酶(p38MARK)和过氧化物酶体增殖物激活受体α(PPARα)等信号转导通路,参与机体内的脂代谢途径。目前对Adipo Q介导的脂代谢信号转导通路的研究已有了一定进展。本文就Adipo Q及其受体的结构,以及Adipo Q及其受体对脂代谢的调控机制进行了综述。     

脂联素对动物细胞增殖和程序性死亡调控作用的研究进展

细胞是生命活动的基本单位,生命体通过协调细胞的增殖、分化、死亡调节机体正常的生理功能,维持内环境稳态。脂联素(adiponectin, ADPN)是一种具有多方面功能的脂肪因子,它在动物细胞代谢调节和维持细胞能量稳态方面发挥着重要作用。脂联素能够通过相关信号通路抑制细胞的异常增殖、分化和焦亡,双向调控细胞自噬,增强细胞自噬水平,阻止细胞发生异常自噬,并具有抗细胞凋亡作用。文章综述了脂联素及其受体的结构和生物学功能,回顾了脂联素对动物不同类型细胞增殖、凋亡、自噬、焦亡等事件的调控及机制方面的研究进展,以期为开展基于脂联素及其受体相关途径的动物抗衰老、抗炎症、抗癌变等研究提供新的方向和靶点。     

脂联素与脂联素受体的研究进展

脂联素是脂肪细胞特异分泌的细胞因子，起调节糖类和脂类代谢的作用。作者就脂联素的来源、结构，对糖和脂代谢的调控、表达及其受体的研究进展作一综述。     

脂联素及其受体的研究进展及在生殖中的作用

脂联素是一种由脂肪组织分泌的具有多种生物学功能的特殊蛋白,在增强脂肪酸氧化、抗炎症反应、抗糖尿病等方面起重要作用。脂联素通过AdipoR1和AdipoR2这两种受体的介导经过AMPK、PPAR、p38MAPK等信号通路来发挥生物学作用。脂联素及其受体AdipoR1和AdipoR2能在多种组织器官中表达,AdipoR1主要在肌肉组织中表达,AdipoR2则高表达于肝脏组织。此外,脂联素及其受体还能在下丘脑、垂体、子宫、胚胎等多种生殖腺和生殖组织中表达,说明脂联素在调控动物生殖及胚胎生长发育方面起重要作用。     

脂联素受体激动剂(AdipoRon)对鸡成骨细胞增殖和凋亡的影响

脂联素受体激动剂(AdipoRon)是人工合成的与脂联素(ADPN)有相似作用的口服活性小分子,研究显示ADPN可调节成骨细胞生长和分化,但AdipoRon是否具有类似的功能目前鲜见报道。本试验主要研究AdipoRon对鸡成骨细胞的影响。从14日龄鸡胚额骨中分离获得成骨细胞,细胞培养第4日,分别添加100,200 mg/L AdipoRon处理成骨细胞,处理72 h后,MTT法检测细胞增殖活性,并进行碱性磷酸酶(ALP)染色。Real-time PCR检测脂联素受体1(AdipoR1)、脂联素受体2(AdipoR2)、成骨细胞成熟标志基因骨钙素(osteocalcin,OC)、Ⅰ型胶原α2链(alpa2 of type I collegen,COL1A2)、细胞凋亡相关基因Caspase-3、Bcl-2及Bax的基因表达量,计算Bcl-2与Bax基因表达量的比值。结果显示,100,200 mg/L AdipoRon处理后的成骨细胞正常形态消失,细胞数量减少,体积变小,细胞核明显固缩,细胞存活率极显著降低(P<0.01)。AdipoRon可增加成骨细胞中AdipoR1、AdipoR2、OC、Bcl-2、Bax和Caspase-3的表达量(P<0.05),并呈剂量依赖性,但对COL1A2和Bcl-2/Bax的表达无显著性影响。结果表明,100,200 mg/L AdipoRon均可促进鸡成骨细胞AdipoR1/2的表达,且能抑制成骨细胞的增殖,促进成骨细胞的成熟及凋亡。     

脂联素研究进展及其在畜禽生产中的应用前景

脂联素(Adiponectin)是主要由脂肪细胞分泌的细胞因子,通过受体(AdipoR1或Adi- poR2)作用于相关组织,激活过氧化物酶体增殖物激活受体α(PPARα)和AMP激酶(AMPK)信号转导通路,发挥调节胰岛素敏感性、维持机体能量平衡、调控体脂沉积等功效。     

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。     

绝食对九龙牦牛体重、血清激素和生化指标的影响

本试验旨在研究冷季绝食应激时九龙牦牛体重、血清激素和生化指标的变化。选择8头健康无病、生长发育良好的2岁九龙牦牛8头,体重为(90.75±8.66)kg,按体重相近的原则随机分为对照组和绝食组,每组4个重复,每个重复1头牛。对照组正常饲喂,绝食组牦牛做断料处理。试验期7 d。分别在试验开始后的第1、3、5、7天称重和通过颈静脉采血。结果表明:绝食7 d后牦牛的体重显著降低(P0.05),血清中葡萄糖、胰岛素含量显著下降(P0.05),血清非酯化脂肪酸、甘油三酯、脂联素和胰高血糖素含量显著升高(P0.05),血清中糖异生前体物质丙酸、乳酸的含量显著降低(P0.05),而血清中来源于体储降解的甘油、β-羟丁酸的含量显著升高(P0.05),血清中糖异生关键酶丙酮酸羧化酶、果糖1,6二磷酸酶、磷酸烯醇式丙酮酸羧激酶、葡萄糖六磷酸酶的活性均显著升高(P0.05)。结果提示,绝食7 d后牦牛开始大量动用体储,提高糖异生代谢过程,维持机体代谢的正常需要,保证血清葡萄糖含量的稳定以维持生命。     

Changes in circulating adiponectin and metabolic hormone concentrations during periparturient and lactation periods in Holstein dairy cows

Although our previous report demonstrated that adiponectin and AdipoR1 gene expressions changed among different lactation stages in the bovine mammary gland, its in vivo kinetics remain unclear in ruminant animals. In this study, we investigated the changes in circulating concentrations of adiponectin, as well as other metabolic hormones and metabolites, (i) during the periparturient period and (ii) among different lactation stages, in Holstein dairy cows. In experiment 1, serum adiponectin concentrations increased after parturition. Serum insulin concentrations were lower in the postpartum than prepartum period, whereas serum growth hormone (GH) concentrations increased in the postpartum period. Serum nonesterified fatty acids (NEFA) levels were increased during the postpartum period and were dependent on the parity. In experiment 2, there was no significant difference in plasma adiponectin concentrations among lactational stages. Plasma insulin concentrations tended to be lower in early lactation while plasma GH levels tended to be higher. Plasma NEFA concentrations were significantly lower in mid‐ and late‐lactation stages than non‐lactation stages. These findings indicate that elevation of serum adiponectin might be involved in energy metabolism just around parturition, and might exert its action through regulation of receptor expression levels in target tissues in each lactational stage in Holstein dairy cows.     

Serum adipokine concentrations in dogs with diabetes mellitus: a pilot study

This study was conducted to determine whether serum adipokine concentrations differed between healthy dogs and dogs with diabetes mellitus (DM). To accomplish this, 19 dogs with newly diagnosed DM were compared to 20 otherwise healthy dogs. The serum concentrations of visfatin, leptin, IL-1β, IL-6, IL-18, and TNF-α were significantly higher in diabetic dogs than in healthy dogs, whereas the serum adiponectin concentrations were lower in diabetic dogs. However, there were no significant differences in the IL-10 and resistin levels between groups. The serum leptin concentrations in diabetic dogs with and without concurrent disorders differed significantly. Treatment with insulin induced a significant decrease in IL-6 in diabetic dogs without concurrent disorders. These results show that the clinical diabetic state of dogs could modulate the circulating visfatin and adiponectin concentrations directly, while upregulation of leptin was probably a result of concurrent disorders rather than an effect of persistent hyperglycemia as a result of DM.     

武定鸡脂联素基因多态性分析

[目的]对武定鸡脂联素基因（NC_006096）第1外显子上的c.A99G突变位点进行多态性分析。[方法]翅静脉采集67只武定鸡全血,提取基因组DNA,采用PCR-RFLP法分析Hsp92Ⅱ限制性内切酶对PCR产物进行单酶切的结果。[结果]在c.A99G同义突变位点上存在AA、AB和BB 3种基因型,其中A基因频率为0.686 6,B基因频率为0.313 4;PIC=0.337 8,表明该位点为中度多态位点;χ²适合性检验表明,脂联素基因c.A99G位点处于平衡状态。[结论]采用PCR-RFLP法可有效检测武定鸡脂联素基因c.A99G突变,该位点有3种基因型,等位基因呈中度遗传多态水平且处于平衡状态。     

皖南花猪骨骼肌AdpR和MyHCmRNA表达的发育性变化

摘要：为探讨皖南花猪骨骼肌组织中脂联素受体（AdpRl、AdpR2）和不同类型肌球蛋白重链（MyHC）mRNA的发育性变化及性别差异,选择0（出生当天）、30、45、90、180日龄的皖南花猪公母各5头,以B～Actin为内标,采用△△Ct相对定量实时荧光PCR方法对背最长肌和半腱肌中AdpRl、AdpR2、MyHCI、MyHC2a、MyHC2b和My-HC2xmRNA进行定量分析。结果显示,背最长肌和半腱肌AdpRl、AdpR2、MyHCl、MyHC2a、MyHC2b和My—HC2XmRNA的表达都有显著或极显著的发育变化规律（P〈0．05或P〈0．01）。总体上AdpRl、AdpR2、My—HC2a、MyHC2b和MyHC2XmRNA在背最长肌显著或极显著高于半腱肌（P〈0．05或P〈0．01）;MyHClmRNA在背最长肌极显著低于半腱肌（P〈0．01）。半腱肌MyHClmRNA在母猪显著大于公猪（P〈0．05）,而MyHC2amRNA在母猪显著小于公猪（P〈0．05）。背最长肌和半腱肌AdpR2mRNA的表达分别与MyHCl正相关（P〈0．05）,半腱肌AdpRlmRNA的表达与MyHC2x正相关（P〈0．05）。结果表明,皖南花猪骨骼肌组织中AdpR和MyHC的基因表达有特定的发育模式和组织特异性,且有一定性别差异。     

Expression and localization of adiponectin and its receptors in ovarian follicles during different stages of development and the modulatory effect of adiponectin on steroid production in water buffalo

Adiponectin is an adipocyte‐derived hormone regulating energy metabolism, insulin sensitivity and recently found to regulate reproduction. The current study was carried out to investigate gene and protein expression, immunolocalization of adiponectin and its receptors AdipoR1 and AdipoR2 in ovarian follicles of different developmental stages in water buffalo (Bubalus bubalis) and to investigate the effect of adiponectin on steroid production in cultured bubaline granulosa cells. qPCR, western blotting and immunohistochemistry were applied to demonstrate mRNA expression, protein expression and immunolocalization, respectively. The results indicate that adiponectin, AdipoR1 and AdipoR2 were present in granulosa cells (GC) and theca interna (TI) of ovarian follicles and the expression of adiponectin, AdipoR1, AdipoR2 in GC and AdipoR1 and AdipoR2 in TI increased with increase in follicle size (p < .05). Expression of adiponectin was high in small and medium size follicles in TI. The adiponectin and its receptors were immunolocalized in the cytoplasm of GC and TI cells. Further, in the in‐vitro study, GCs were cultured and treated with recombinant adiponectin each at 0, 1 and 10 µg/ml alone or with follicle stimulating hormone (FSH) at 30 ng/ml) or Insulin‐like growth factor I (IGF‐I) at 10 ng/ml for 48 hr after obtaining 75%–80%s confluency. Adiponectin at 10 µg/ml increased IGF‐I‐induced estradiol (E₂) and progesterone (P₄) secretion and FSH‐induced E₂ secretion from GC and also increased the abundance of factors involved in E₂ and P₄ production (cytochrome P45019A1 [CYP19A1] and 3‐beta‐hydroxysteroid dehydrogenase [3β‐HSD]). In conclusion, this study provides novel evidence for the presence of adiponectin and its receptors in ovarian follicles and modulatory role of adiponectin on steroid production in buffalo.     

藏羊脂联素基因多态性及其与产肉性能的相关性分析

利用高分辨率熔解曲线技术对176头2周岁的甘肃藏羊（欧拉型、甘加型、乔科型）脂联素基因SNPs位点进行检测,运用GLM模型将检测到的SNPs位点与部分胴体及肉质性状的相关性进行了分析.结果表明：在脂联素第2外显子发现＋67G＞C突变使编码氨基酸由谷氨酸突变为谷氨酰胺;GG、GC基因型个体的宰前活重、胴体重均显著高于CC型（P＜0.05）.说明脂联素基因该位点可能是影响藏羊胴体及肉质性状的主效QTL或与之紧密连锁,可作为藏羊高档羊肉生产的候选分子标记.