Marine Sulfated Polysaccharides: Preventive and Therapeutic Effects on Metabolic Syndrome: A Review

Metabolic syndrome is the pathological basis of cardiovascular and cerebrovascular diseases and type 2 diabetes. With the prevalence of modern lifestyles, the incidence of metabolic syndrome has risen rapidly. In recent years, marine sulfate polysaccharides (MSPs) have shown positive effects in the prevention and treatment of metabolic syndrome, and they mainly come from seaweeds and marine animals. MSPs are rich in sulfate and have stronger biological activity compared with terrestrial polysaccharides. MSPs can alleviate metabolic syndrome by regulating glucose metabolism and lipid metabolism. In addition, MSPs prevent and treat metabolic syndrome by interacting with gut microbiota. MSPs can be degraded by gut microbes to produce metabolites such as short chain fatty acids (SCFAs) and free sulfate and affect the composition of gut microbiota. The difference between MSPs and other polysaccharides lies in the sulfation pattern and sulfate content, therefore, which is very important for anti-metabolic syndrome activity of MSPs. This review summarizes the latest findings on effects of MSPs on metabolic syndrome, mechanisms of MSPs in treatment/prevention of metabolic syndrome, interactions between MSPs and gut microbiota, and the role of sulfate group and sulfation pattern in MSPs activity. However, more clinical trials are needed to confirm the potential preventive and therapeutic effects on human body. It may be a better choice to develop new functional foods containing MSPs for dietary intervention in metabolic syndrome.     

嗜酸乳杆菌对运输前后马肠道菌群的影响

【目的】旨在研究运输应激对马肠道菌群结构的影响,并探讨嗜酸乳杆菌对马运输应激的预防作用。【方法】试验选取10匹24月龄的伊犁马,随机均分为试验组和对照组。所有马均进行环境适应1周后,试验组开始在饲喂基础饲粮外补饲嗜酸乳杆菌胶囊,对照组不补饲。饲喂15 d之后,试验组与对照组在第16天同时开展里程约400 km的运输试验,分别于运输前后采集对照组马颈静脉血液进行生理指标检测,并在喂菌前、喂菌15 d后和运输8 h后采集马粪便,试验组喂菌前样品设为A1组,喂菌15 d后样品设为A2组,运输8 h后样品设为A3组,对照组运输8 h后样品设为T3组。采用Illumina MiSeq高通量测序方法对马肠道菌群多样性进行分析。【结果】运输前后血液生理指标测定结果显示,对照组中间细胞比率和血红蛋白在运输8 h后呈现显著性下降(P<0.05),血红蛋白浓度在运输8 h后极显著降低(P<0.01)。补饲嗜酸乳杆菌和运输均能够引起马肠道菌群组成出现差异,补饲嗜酸乳杆菌增加了理研菌科RC9(Rikenellaceae＿RC9＿gut＿group)、毛螺菌科AC2044属(Lachnospirac...     

饲料添加剂调节畜禽肠道菌群及其生长性状的研究进展

肠道菌群影响畜禽生长发育以及相关多个重要经济性状。就多种饲料添加剂调节畜禽肠道菌群及其生长性状的研究进展进行综述。从生物学机制出发,介绍了饲料添加剂对畜禽肠道菌群及其生长性状的影响和菌群移植影响宿主生长性状的研究进展,总结了通过饲料添加剂影响畜禽肠道菌群、改善畜禽生长性能的应用实践。     

Phylogenetic analysis of intestinal bacteria of freshwater salmon Salmo salar and sea trout Salmo trutta trutta and diet

The microbial diversity of culturable intestinal microflora of wild freshwater salmonid fishes salmon Salmo salar and sea trout Salmo trutta trutta juveniles (0+ years old) from the same environmental conditions were investigated by means of molecular identification techniques and analysis of diet. Significant differences in the intestinal microbial diversity were observed in different fish species. The predominant group in the intestinal tract of the salmon comprised representatives of the Enterobacteriaceae family (23%), Plesiomonas (19.2%) and Carnobacterium (15.3%). Predominant microbiota in sea trout intestinal tract were Enterobacteriaceae (52%), Aeromonas (22%) and Pseudomonas (14%). The results show that Enterobacteriaceae were predominant in the intestinal tract of the salmon and the sea trout juveniles raised on diets of different compositions. However, molecular identification of the intestinal microbiota at the species or genus level revealed differences in these fish species. Bacteria in the hindgut of salmon included Pragia and Serratia. However, bacteria in the gut contents of sea trout from the Enterobacteriaceae family were Buttiauxella, Enterobacter, Moellerella, Pantoea, Rahnella and Tiedjeia arctica. A novel phylotype of T. arctica is harbored in the intestinal tract of wild salmon, and may correspond to a previously undescribed species.     

基于Web of Science数据库的犬猫肠道菌群研究热点的可视化分析

为全面、客观分析犬猫肠道菌群研究的发展脉络和热点方向,本研究采用文献计量学方法,检索Web of Science核心数据库近20年关于犬猫肠道菌群的文章,应用软件Citespace、VOSviewer和Microsoft Excel对发文量、发文时间、发文国家和机构、发文作者、发文期刊、文献共被引频次和关键词进行分析。结果表明：1）在犬猫肠道菌群领域,近20年Web of Science共发表相关文献413篇,且发文量呈逐年上升趋势。2）美国得克萨斯A&M大学是发文最多的机构,形成了以学者Suchodolski和 Swanson为核心的学术共同体;PLOS ONE是发文量最多的期刊。3）研究方向可分为4方面,分别是营养素对犬猫肠道菌群的影响、益生菌对犬猫肠道菌群的影响、疾病和犬猫肠道菌群紊乱的相关性以及肥胖和犬猫肠道菌群的相关性。犬猫食物补充剂如何通过调控肠道菌群进而提高健康水平是未来研究的关注重点。综上,近年来犬猫肠道菌群相关研究正逐步受到研究者的关注,本研究为改善犬猫的健康水平和生活质量提供重要的参考依据。     

Potential use of ground brown rice for weanling pigs

The purpose of the current study was to assess the effects of substituting corn with ground brown rice on growth performance, immune status, and gut microbiota in weanling pigs. Seventy-two weanling pigs (28 d old with 6.78 ± 0.94 kg body weight [BW]) were randomly allotted to two dietary treatments with six pens and six pigs (three barrows and gilts) per pen within a randomized complete block design. The control pigs were fed a typical diet for weanling pigs based on corn and soybean meal diet (control diet: CON), and the other pigs were fed a formulated diet with 100% replacement of corn with ground brown rice for 35d (treatment diet: GBR). Growth performance, immune status, and gut microbiota of weanling pigs were measured. The substitution of corn with GBR did not affect growth performance or diarrhea frequency. Additionally, there were no differences in white blood cell number, hematocrit, cortisol, C-reactive protein, and serum tumor necrosis factor-alpha levels between pigs fed CON or GBR for the first 2 wk after weaning. However, weanling pigs fed GBR had lower (P < 0.05) serum transforming growth factor-beta 1 level than those fed CON. Furthermore, weanling pigs fed GBR had increased (P < 0.05) relative abundance of phylum Firmicutes and genus Lactobacillus and Streptococcus and decreased (P < 0.05) relative abundance of phylum Bacteroidetes and genus Clostridium and Prevotella in the gut microbiota compared with those fed CON. In conclusion, there was no significant difference in growth performance when corn was replaced with ground brown rice in diets for weanling pigs. Furthermore, the substitution of corn with ground brown rice in weaning diet modulated immune status and gut microbiota of pigs by increasing beneficial microbial communities and reducing harmful microbial communities. Overall, ground brown rice-based diet is a potential alternative to corn-based diet without negative effects on growth performance, immune status, and gut microbiota changes of weanling pigs.     

鱼类肠道菌群影响因子研究进展

肠道菌群在维持肠道健康、促进肠道发育、抵抗病原入侵、调节机体能量吸收和脂质代谢过程中均发挥重要作用。在鱼类学研究中,由于种类繁多、食性差异大、生存环境复杂多变,导致鱼类肠道菌群方面的研究面临巨大挑战。本文在总结常见鱼类肠道微生物组成的基础上,着重介绍了鱼类饵料组成、水环境因子、物种、基因型、发育阶段、养殖模式及投喂策略对鱼类肠道菌群影响的相关研究进展,并对目前研究中存在的问题进行了剖析,以期为鱼类肠道菌群研究提供一定的参考依据。     

凡纳滨对虾和罗氏沼虾肠道微生物及抗生素抗性基因多样性分析

探究凡纳滨对虾和罗氏沼虾肠道微生物及抗生素抗性基因(antibiotic resistance genes, ARGs)种类的差异。通过高通量测序和变性梯度凝胶电泳(denaturing gradient gel electrophoresis, DGGE)技术分析2种虾肠道微生物群落结构差异和微生物多样性,并运用PCR方法检测了2种虾肠道细菌常见38种ARGs的携带情况。结果显示,获得凡纳滨对虾和罗氏沼虾肠道细菌有效序列分别为42 795和40 713条,物种注释单元(operational taxonomic unit, OTU)数目分别为124和82,分类地位明确的细菌种类分别隶属5个门、17个属和5个门、16个属。凡纳滨对虾肠道细菌的优势类群为变形菌门,所占比例为75.45%,优势菌属为副球菌属(25.83%)和不动杆菌属(25.24%);罗氏沼虾肠道细菌的优势类群是厚壁菌门(49.74%),优势菌属为乳球菌属(49.01%)和弧菌属(29.98%)。凡纳滨对虾肠道细菌(2.19)Shannon指数高于罗氏沼虾肠道细菌(1.78),表明前者肠道细菌多样性大于后者。DGGE图谱的分析结果与高通量测序一致,2种虾肠道细菌种类差异很大。PCR结果显示,凡纳滨对虾肠道细菌携带15种ARGs,罗氏沼虾肠道细菌携带14种ARGs。本实验表明凡纳滨对虾肠道细菌的群落种类多样性、OTU丰富度、物种总数和ARGs种类均高于罗氏沼虾肠道细菌,为后续肠道微生物资源的挖掘提供了理论依据。     

鱼类消化道菌群与碳水化合物代谢

碳水化合物氧化分解是鱼类能量的重要来源。由于碳水化合物来源广泛、价格相对低廉,饲料中添加适量碳水化合物,不仅可以降低饲料成本,而且可以节约蛋白原料,减少氨氮排放。然而以往研究表明,鱼类摄入超量碳水化合物时会出现抗病力受损、生长迟缓、脂肪肝、死亡率升高等问题。鱼类消化道微生物参与宿主的糖、脂类和蛋白质等代谢过程,对动物营养代谢有重要的调控作用。提高鱼类对饲料的利用率,对鱼类增产、渔民增收具有重要的现实意义。本研究综述了鱼类对碳水化合物的代谢,以鱼类消化道微生物为出发点,阐述了鱼类消化道微生物调控碳水化合物代谢的方式与可能机制,旨在为鱼类高效利用碳水化合物以及节约饲料中蛋白质提供新视角。     

投喂鲍内脏多糖对罗非鱼肠道菌群结构的影响

利用PCR-DGGE和Illumina测序技术研究了罗非鱼(Oreochromisniloticus)肠道菌群结构及饲喂鲍内脏多糖后罗非鱼肠道菌群的动态变化。在罗非鱼肠道中检测到13个门的细菌,其中梭杆菌门(Fusobacteria,77.84%)为优势菌门,拟杆菌门(Bacteroidetes, 8.59%)、衣原体门(Chlamydiae, 6.18%)、变形菌门(Proteobacteria, 5.84%)和放线菌门(Actinobacteria, 1.20%)为次优势菌门,还检测到Saccharibacteria等8个菌门和一些未知类群。在属的水平上,优势菌属为鲸杆菌属(Cetobacterium)、Neochlamydia、邻单胞菌属(Plesiomonas)和不动杆菌属(Acinetobacter),分别占77.84%、5.796%、2.64%和1.13%,还有一个紫单胞菌科(Porphyromonadaceae)的未知属,占8.29%。此外还有分枝杆菌属(Mycobacterium)等6个菌属和一些未知属。投喂添加鲍多糖的饲料对罗非鱼肠道微生物的构成造成了明显影响,饲喂鲍多糖的处理组和饲喂普通饲料的对照组样品分别聚为两大类。投喂添加鲍多糖饲料后,放线菌门、Saccharibacteria、疣微菌门和TM6_Dependentiae的丰度显著下调;在属的水平上,邻单胞菌属、鲸杆菌属的丰度上调;Neochlamydia、不动杆菌属、分枝杆菌属、Alsobacter、Aquicella、假单胞菌属、气单胞菌属、Alpinimonas等属的丰度下调。其中分枝杆菌属、Alsobacter、Aquicella和邻单胞菌属的丰度与对照差异显著(P0.05)。在种水平上,一些潜在致病菌,如鲍曼不动杆菌(Acinetobabacterbaumannii)、龟分枝杆菌(Mycobacteriumabscessus)、Aeromonas sharmana、耐酪酸冢村菌(Tsukamurella tyrosinosolvens)、铜绿色假单胞菌(Pseudomonas aeruginosa)等的丰度下调,其中龟分枝杆菌和耐酪酸冢村菌与对照差异显著(P0.05),而鲸杆菌属等有益菌的丰度上调。本研究从肠道微生物的角度来研究鲍内脏多糖对宿主的影响,为海洋生物活性物质的功效评价提供了新思路,也为鲍内脏活性物质的开发利用、益生元的研制等奠定理论基础。