铜肠道稳态平衡调控机制研究进展

铜是动物机体必需的微量元素之一,肠道细胞内铜的吸收、储存、释放、转运对肠道铜稳态的维护至关重要,肠道铜稳态的失衡使肠道细胞脱落导致肠道功能障碍。随着对肠道铜转运因子与靶细胞器研究的逐步深入和完善,人们取得了新的发现和认识。作者综述了胞内的线粒体、高尔基体、胞浆分别与铜伴侣蛋白、铜转运蛋白的结合途径,阐明了铜特异性转运蛋白（CTR1）的表达机制,铜转出蛋白（ATP7A、ATP7B）在高铜情况下的再分配机制及其他上皮细胞组织铜的稳态机制。根据以上机制得出,肠细胞亚细胞器的铜转运蛋白的表达位置和表达水平随其内环境铜水平的变化而趋于肠稳态形式变化。此结论为揭示肠道铜稳态机制提供了一定的理论依据。     

黄烷醇对动物胰岛素抵抗状态下血糖稳态的调控作用及其机理

血糖稳态对动物机体各项生理功能的正常发挥起着重要作用。黄烷醇是一类来源于植物的生物类黄酮物质,研究表明,黄烷醇可以平衡动物胰岛素抵抗状态下的血糖稳态,其机制可能涉及调节肠道碳水化合物的消化吸收效率、增加胰高血糖素样肽-1的活性、促进胰岛β细胞分泌胰岛素、提升肝糖原合成效率以及降低机体炎症来保护胰岛素信号转导途径不被破坏等方面。本文将黄烷醇对动物胰岛素抵抗状态下血糖稳态的调控作用及其机理作一概述,为其在生产和临床上的应用提供依据。     

微量元素铜在动物体内的转运代谢过程

铜是所有生物必需的微量元素之一,在生物体的生长和发育过程中发挥着重要功能。为进一步研究铜在机体内的转运代谢过程,本文就微量元素铜在血液、细胞膜、细胞内的运输及其排泄途径进行了阐述。     

The Effect of Dietary Sulphate Copper Supplementation on Growth Performance, Intestinal Digestive Enzymes and Absorptive Transporters in Weanling Pigs

The experiment was conducted to assess the effects of dietary supplementation of Cu on the growth performance, digestive enzymes, tissue minerals and absorptive transporters in small intestinal mucosa of weanling pigs. One hundred crossbred pigs weaned at 28 ± 2 d of age were assigned randomly to one of the following diets with 5 replicates: corn-soybean basal diet with 10, 100, 175, 250 mg/kg of Cu as CuSO₄•5H₂O. The results showed that 250 mg/kg Cu had a positive effect (P < 0.05) on average daily gain, daily feed intake and ratio of gain/feed. Compared to 10 mg/kg Cu, higher Cu had significant effect on the apparent digestibility of protein and fat (P < 0.05). The supplementing of Cu improved amylase and lipase activity in jejunum content and lipase in pancreas (P < 0.05) and had no effect on intestinal morphology. The liver Cu elevated approximately 4-fold in pigs fed diet with 250 mg/kg Cu compared with pigs fed diet with 10 mg/kg Cu, no increases were observed in pigs receiving the lower level of Cu (100 and 175 mg/kg). Both Fe and Zn contents in kidney and liver were not affected by Cu supplementation. There was no positive effect (P > 0.05) of Cu supplementation on PepT1 (peptide transporter 1) and SGLT1 (sodium/glucose cotransporter) mRNA abundance in intestinal mucosa. However, higher supplementing level (250 mg/kg) significantly elevated the DMT1 (divalent metal transporter) mRNA abundance in duodenum mucosa. These results suggested that dietary supplementation with 250 mg/kg Cu could improve growth performance, nutrient digestibility and intestinal enzyme activities of weanling pigs.     

The Effect of Dietary Sulphate Copper Supplementation on Growth Performance, Intestinal Digestive Enzymes and Absorptive Transporters in Weanling Pigs

The experiment was conducted to assess the effects of dietary supplementation of Cu on the growth performance,digestive enzymes,tissue minerals and absorptive transporters in small intestinal mucosa of weanling pigs.One hundred crossbred pigs weaned at 28±2 d of age were assigned randomly to one of the following diets with 5 replicates:corn-soybean basal diet with 10,100,175,250 mg/kg of Cu as CuSO4·5H2O.The results showed that 250 mg/kg Cu had a positive effect (P0.05) on average daily gain,daily feed intake and ratio of gain/feed.Compared to 10 mg/kg Cu,higher Cu had significant effect on the apparent digestibility of protein and fat (P0.05).The supplementing of Cu improved amylase and lipase activity in jejunum content and lipase in pancreas (P0.05) and had no effect on intestinal morphology.The liver Cu elevated approximately 4-fold in pigs fed diet with 250 mg/kg Cu compared with pigs fed diet with 10 mg/kg Cu,no increases were observed in pigs receiving the lower level of Cu (100 and 175 mg/kg).Both Fe and Zn contents in kidney and liver were not affected by Cu supplementation.There was no positive effect (P0.05) of Cu supplementation on PepT1 (peptide transporter 1) and SGLT1 (sodium/glucose cotransporter) mRNA abundance in intestinal mucosa.However,higher supplementing level (250 mg/kg) significantly elevated the DMT1 (divalent metal transporter) mRNA abundance in duodenum mucosa.These results suggested that dietary supplementation with 250 mg/kg Cu could improve growth performance,nutrient digestibility and intestinal enzyme activities of weanling pigs.     

The Effect of Dietary Sulphate Copper Supplementation on Growth Performance,Intestinal Digestive Enzymes and Absorptive Transporters in Weanling Pigs1

The experiment was conducted to as- sess the effects of dietary supplementation of Cu on the growth performance, digestive enzymes, tissue minerals and absorptive transporters in small intestinal mucosa of weanling pigs. One hundred crossbred pigs weaned at 28 ＋ 2 d of age were assigned randomly to one of the following diets with 5 replicates：corn-soy- bean basal diet with 10,100,175,250 mg/kg of Cu as CuSO4·5H20. The results showed that 250 mg/kg Cu had a positive effect （ P 〈 0.05） on average daily gain, daily feed intake and ratio of gain/feed. Com- pared to 10 mg/kg Cu, higher Cu had significant effect on the apparent digestibility of protein and fat （P 〈 0.05 ）. The supplementing of Cu improved am- ylase and lipase activity in jejunum content and lipase in pancreas （ P 〈 0.05） and had no effect on intestinalmorphology. The liver Cu elevated approximately 4- fold in pigs fed diet with 250 mg/kg Cu compared with pigs fed diet with 10 mg/kg Cu, no increases were observed in pigs receiving the lower level of Cu （100 and 175 mg/kg）. Both Fe and Zn contents in kidney and liver were not affected by Cu supplemen- tation. There was no positive effect （ P 〉0.05） of Cu supplementation on PepT1 （peptide transporter 1 ） and SGLT1 （sodium/glucose cotransporter） mRNA abundance in intestinal mucosa. However, higher sup- plementing level （250 mg/kg） significantly elevated the DMT1 （divalent metal transporter） mRNA abun- dance in duodenum mucosa. These results suggested that dietary supplementation with 250 mg/kg Cu could improve growth performance, nutrient digestibil- ity and intestinal enzyme activities of weanling pigs.     

血管紧张素转换酶2在维持肠道稳态中的作用

血管紧张素转换酶2(ACE2)是首先克隆出的人类血管紧张素转换酶(ACE)的同源基因,是肾素-血管紧张素系统(RAS)的关键调节因子,其主要通过水解血管紧张素Ⅱ(AngⅡ)生成血管紧张素1-7[Ang(1-7)]从而发挥舒张血管、抗炎、抗增殖等作用。近期研究发现,ACE2不仅对心血管和肾功能等具有明显的调控作用,对抑制肠道炎症、维持肠道稳态、保护肠道健康等同样具有积极的影响。当前对ACE2在肠道健康领域的研究较少。论文就ACE2通过影响肠道微生态对维持肠道稳态作用的研究进行综述,为发掘ACE2的新功能提供参考。     

有机锌对动物肠道健康的调控作用研究进展

肠道既是动物机体消化吸收营养物质的主要器官,也是体内最大的免疫器官,同时还发挥着重要的屏障功能,因此肠道健康是动物健康的必要条件。锌是动物必需的微量元素之一,对动物生长发育、抗氧化和免疫等生理功能具有重要调控作用。长期以来,饲料中补充营养性锌源以无机硫酸锌为主,近年来蛋氨酸锌、乳酸锌和甘氨酸锌等有机锌源的使用越来越普遍。关于有机锌对动物肠道健康的调控作用已成为锌营养领域研究热点之一。本文从有机锌对肠道黏膜屏障、肠道免疫和肠道生物屏障的影响等方面综述了有机锌对动物肠道健康的调控作用,为有效利用有机锌改善动物健康提供重要的科学依据和理论支撑。     

家畜认知功能及其调控机制

动物认知是指动物受到环境变化的刺激或应激时,对其刺激做出的关联性学习和记忆,并做出适当的决定与反应能力。研究表明,家畜的认知功能与其繁殖性能和畜牧生产密切相关。这篇综述重点对近年来家畜认知行为和认知功能的国内外研究进展及认知对家畜繁殖、生产性能等方面的影响进行概述,较系统地阐述了“神经血管单元”、表观遗传修饰以及线粒体对认知功能的调控机制,为家畜认知行为和认知功能的深入研究提供重要的参考价值。     

炎症反应致肌肉蛋白质降解机理的研究进展

骨骼肌消耗是肌肉蛋白质合成减少和（或）分解代谢加快的结果,可发生于多种疾病状态下,如病原菌感染、创伤、肿瘤等。目前越来越多的研究结果表明系统性炎症在肌肉蛋白质降解过程中扮演着重要角色。作者综述了近年来关于炎症反应导致肌肉蛋白质降解机理的研究进展,主要包括泛素-蛋白酶体途径、自噬溶酶体降解途径及PI3K/Akt、p38/MAPK、NF-κB等多条信号通路,为开发新的方法治疗肌肉降解提供参考。     

Research Progress on the Mechanisms of Inflammation-induced Muscle Protein Degradation

Skeletal muscle wasting is a consequence of the decrease of muscle protein synthesis and/or degradation acceleration,and often accompanies with various serious diseases,such as pathogen infection,injury and tumor.At present,many studies have shown that the systemic inflammation is playing an important role in the process of muscle wasting.Based on the current literature,we present an overview of the molecular and cellular mechanisms that contribute to the inflammation-induced muscle wasting,mainly including the ubiquitin-proteasome pathway (UPP),autophagy-lysosomal pathway (ALP),PI3K/Akt pathway,p38/MAPK pathway and NF-κB pathway,which hope to offer the guidance for the treatment of skeletal muscle wasting.     

断奶仔猪应激期肠道健康及营养调控的研究进展

仔猪断奶后需经历环境变化、饲粮转变以及自身肠道结构与功能改变,易发生断奶应激,直接影响养猪生产的效率.因此,研究缓解断奶仔猪应激的调控措施对养猪生产具有重要意义.本文分别从肠道健康和营养调控两方面出发,对近年来关于仔猪断奶应激的调控措施进行综述,以期为进一步研究仔猪断奶应激和健康养殖提供理论依据和调控思路.     

家畜铜中毒研究进展

铜中毒是由于家畜摄食铜过多,或因肝细胞损伤,铜在肝脏等组织中大量蓄积,而突然释放进入血液循环所引起的一种重金属中毒性疾病。在生产中,家畜铜中毒屡见发生。文章归纳了铜中毒的发病特点和发病原因;总结了铜中毒的3 种发病机理,铜中毒的保护机制,铜与氧自由基的产生机制,铜毒理;论述了铜中毒的诊断依据、诊断指标和诊断方法;提出了铜中毒的综合性预防措施、治疗原则和治疗药物。为铜中毒病的诊断和防治提供了理论参考。     

短链脂肪酸介导的肠上皮和抗炎调节研究进展

哺乳动物体中的肠道菌群是细菌生态系统的组成部分,从动物出生时起,这些微生物就对免疫系统的发育、功能和调节起着非常重要的作用。当前,越来越多的研究集中在微生物对宿主细胞代谢的影响上。短链脂肪酸(SCFA)作为肠道菌群的一种代谢产物,对肠道稳态的维持具有重要作用。SCFA是肠道上皮细胞的重要燃料,能增强肠屏障功能。作为信号分子,SCFA可以通过细胞表面G蛋白偶联受体(GPCR)发出信号,从而激活控制免疫功能的信号级联反应;还可以通过底物转运蛋白进入细胞,抑制组蛋白脱乙酰化酶(HDAC),最终达到降低肠道炎症反应。本文综述了微生物SCFA的产生及其对肠道黏膜的影响,并通过激活细胞表面GPCR以及抑制组蛋白去乙酰化酶(HDACs)来调节免疫反应的作用。     

产丁酸菌的产酸机制及其在调控肠道健康中的作用研究进展

复杂和多样化的肠道微生物群落对宿主健康发挥着重要作用。产丁酸菌代表了宿主肠道微生态一个重要的功能性群体,多数为革兰阳性厌氧菌。人们发现,该类菌和微生物失调引发的消化道炎症等现象息息相关,因此产丁酸菌成为行业研究热点。产丁酸菌能够利用食物(饲料)中不易消化的碳水化合物合成丁酸,通过调控肠道菌群结构、为肠道上皮细胞供能、增强肠黏膜屏障功能等维护肠道健康,发挥对宿主健康的有益作用。本文从产丁酸菌的生物学分类、消化道产酸机制、肠道炎症调控作用及应用进展等方面做了系统综述,旨在阐明产丁酸菌与宿主健康的互作机制,并提出产丁酸菌的未来发展方向。     

肠上皮细胞中内质网应激与动物肠道炎症机制的研究进展

近年来,内质网应激参与动物炎症性肠病发病机制的研究引起了广泛关注,未折叠或错误折叠的蛋白质在内质网腔中过量积累而引发内质网应激,持续的内质网应激则会导致动物肠黏膜屏障损伤并诱发肠道炎症。本文就内质网应激发生机制、未折叠蛋白质反应及内质网应激与肠道炎症互作机制进行了综述,旨在为防治动物肠道炎症提出新的治疗策略。     

仔猪肠道健康的生物学机制及调控技术研究与应用

断奶应激一直足困扰养猪业的一个难题,也是动物营养学界亟待解决的命题之一.由于幼龄仔猪消化系统和免疫系统都尚未发育成熟,早期断奶容易造成仔猪胃肠道功能紊乱,诱发仔猪断奶综合症.因此,研究仔猪肠道健康,阐明仔猪在断奶前后肠道的变化规律,对于合理制定配方,研究歼发新型的功能性饲料具有十分重要的意义,本文将对近年来国内外对仔猪肠道健康以及功能性饲料的研究进行综述.     

动物肌肉组织蛋白质代谢调控的研究进展

动物肌肉蛋白质是维持机体功能的重要蛋白质,亦是影响肉品质特性的重要因素.研究表明,动物肌肉蛋白质代谢由胰岛素样生长因子-1(IGF?1)/磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(Akt)、肿瘤坏死因子-α(TNF?α)/核转录因子-κB(NF?κB)和肌肉生长抑制素(MSTN)/Smadt等多条信号通路参与完成.此...     

肠道紧密连接及调控通路研究进展

紧密连接是广泛存在于上皮细胞之间的一种黏连复合物,与黏附连接、间隙连接和桥粒共同构成上皮细胞连接复合体,在细胞旁途径发挥重要作用.作为肠屏障的重要组成部分,紧密连接不断受到外界刺激(如病原体、细胞因子、药物、缺血、缺氧等)的威胁,它们能通过影响紧密连接的定位、表达或紧密连接蛋白的磷酸化或去磷酸化,介导多个信号通路来改变...