大鼠肥胖抑郁模型建立及肠道菌群多样性的性别差异研究

目的 肥胖抑郁大鼠模型建立并对比研究肠道菌群多样性的变化。方法 采用高脂饲料喂养和CUMS经典造抑郁方法建立肥胖抑郁模型。将SD大鼠随机分为正常组(C组)、单纯肥胖组(F组)、单纯抑郁组(Y组)和肥胖抑郁组(FY组),整个造模持续5个月，通过糖水偏好实验、旷场实验和强迫游泳实验来评估大鼠抑郁样行为，检测模型鼠血清雌激素水平和血脂4项，并采集各组大鼠粪便样品，通过16S rDNA高通量测序法和生物信息分析软件分析测序结果，比较各组大鼠肠道菌群多样性的变化。结果 高脂饮食和CUMS方法成功制作肥胖抑郁鼠模型，肥胖和肥胖抑郁雌性大鼠雌激素水平明显升高，而雄性各组间雌激素水平无显著性差异。雌雄鼠的FY组肠道菌群α多样性具有显著差别，拟杆菌门和厚壁菌门B/F比值下降，且雄鼠肥胖抑郁B/F值只有雌鼠的一半左右。在属水平，研究结果表明雌雄鼠FY组和F组肠道菌群中Blautia等8个菌群变化一致，但是雌性与雄性在拟杆菌属等各有少量菌群的变化不一致。雌雄肥胖抑郁模型中，肠道菌群革兰氏阳性菌和阴性菌的组成出现差异，G⁺的构成，雌性和雄性均由由厚壁菌门和放线菌门构成，但构成比例不一样。...     

高脂肪日粮和产甲烷菌抑制剂对C57BL/6J小鼠盲肠微生物及脂肪代谢的影响

【目的】本文旨在研究产甲烷菌抑制剂溴氯甲烷(BCM)对采食高、低脂肪水平日粮小鼠的肠道微生物以及脂肪代谢的影响。【方法】选取32只21日龄的雌性C57BL/6J小鼠,随机分成4组:对照低脂日粮组、对照低脂日粮加BCM组、高脂日粮组及高脂日粮加BCM组,每组8个重复,BCM通过饮水添加。饲养周期为6周,试验期结束,采集小鼠血液样品,用于生化指标分析;采集小鼠盲肠内容物,用变性梯度凝胶电泳(DGGE)和real-time PCR技术分析其菌群;气相色谱法分析粪样中短链脂肪酸含量;real-time PCR技术分析肝脏中脂肪代谢相关基因表达。【结果】高脂日粮和BCM处理对小鼠体增重均无显著影响;DGGE图谱中低脂日粮组和高脂日粮组样品聚于不同簇,但对各组总细菌、产甲烷菌和硫还原菌数量无显著影响。高脂日粮组粪样中乙酸占总挥发酸比例显著降低(P0.05);BCM处理显著增加小鼠粪样丙酸比例(P0.05);高脂日粮处理显著影响高密度脂蛋白胆固醇、低密度脂蛋白胆固醇和总胆固醇含量(P0.05);高脂日粮处理促进了甘油三酯水解酶表达(P0.05)。【结论】高脂日粮对小鼠肠道菌群结构以及脂肪代谢有明显影响,而BCM处理影响较小。     

高脂肪日粮和产甲烷菌抑制剂对C57BL/6J小鼠盲肠微生物及脂肪代谢的影响

摘要:【目的】本文旨在研究产甲烷菌抑制剂溴氯甲烷(BCM)对采食高、低脂肪水平日粮小鼠的肠道微生物以及脂肪代谢的影响。【方法】选取32只21日龄的雌性C57BL/6J小,随机分成4组:对照低脂日粮组、对照低脂日粮加BCM组、高脂日粮组及高脂日粮加BCM组,每组8个重复,BCM通过饮水添加。饲养周期为6周,试验期结束,采集小鼠血液样品,用于生化指标分析;采集小鼠盲肠内容物,用变性梯度凝胶电泳(DGGE)和real-time PCR技术分析其菌群;气相色谱法分析粪样中短链脂肪酸含量;real-time PCR技术分析 肝脏中脂肪代谢相关基因表达。【结果】高脂日粮和BCM处理对小鼠体增重均无显著影响;DGGE图谱中低脂日粮组和高脂日粮组样品聚于不同簇,但对各组总细菌、产甲烷菌和硫还原菌数量无显著影响。高脂日粮组粪样中乙酸占总挥发酸比例显著降低(P＜0.05);BCM处理显著增加小鼠粪样丙酸比例(P＜0.05);高脂日粮处理显著影响高密度脂蛋白胆固醇、低密度脂蛋白胆固醇和总胆固醇含量(P＜0.05);高脂日粮处理促进了甘油三酯水解酶表达(P＜0.05)。【结论】高脂日粮对小鼠肠道菌群结构以及脂肪代谢有明显影响,而BCM处理影响较小。     

抗生素和高脂饮食对大鼠肠道乳杆菌多样性的影响

【目的】对正常、高脂、抗生素处理大鼠肠道内乳杆菌进行定性和定量分析,比较不同处理组大鼠肠道乳杆菌的多样性。【方法】应用纯培养和非培养技术(16S r RNA基因序列分析、变性梯度凝胶电泳、实时荧光定量PCR)对大鼠肠道乳杆菌进行分离鉴定和多样性分析。【结果】16S r RNA基因序列同源性分析结果显示,正常组大鼠肠道内分离出的乳杆菌包括约氏乳杆菌(Lactobacillus johnsonii)、鼠乳杆菌(Lactobacillus murinus)、嗜酸乳杆菌(Lactobacillus acidophilus)、罗伊氏乳杆菌(Lactobacillus reuteri)、植物乳杆菌(Lactobacillus plantarum)、肠道乳杆菌(Lactobacillus intestinals)、动物乳杆菌(Lactobacillus animalis)和阴道乳杆菌(Lactobacillus vaginalis);但L.animalis在高脂处理组大鼠肠道内未分离到,L.intestinals和L.vaginalis在抗生素处理组大鼠中未分离到。DGGE结果显示3个组别大鼠肠道中乳杆菌构成差异明显,同一组内样品间相似性较高;相较于正常组和高脂组,抗生素组的丰度较差;且正常组大鼠肠道内乳杆菌的多样性高于高脂组和抗生素组。q-PCR结果显示正常组大鼠肠道乳杆菌的数量明显高于高脂组和抗生素组,高脂组的数量也明显高于抗生素组,且3个组别之间存在显著差异(P0.01)。【结论】高脂饮食及抗生素的使用会减少肠道内乳杆菌多样性。     

泽泻对高脂高糖饮食大鼠肠道菌群多样性的影响

目的研究泽泻对高脂高糖饮食大鼠的降血脂作用与肠道菌群多样性的相关性,并测定高脂高糖饮食大鼠肠道菌群丰度与多样性的变化。方法将32只健康雄性SD大鼠随机分成正常组(control group,CON)、高脂高糖模型组(high-fat and high-sucrose diet group,HFS)、高脂高糖饲料加二甲双胍干预组(metformin treatment group,MET)和高脂高糖饲料加泽泻醇提取物干预组(Alisma orientale extract group,AOE)。每组8只,造模4周后分别灌胃给予相应药物,连续4周。CON组和HFS组灌胃给予生理盐水。检测血清TC、TG、LDL-C及HDL-C水平及其他指标,提取肠道菌群总DNA,分析肠道微生物的变化。结果 HFS组的TC、LDL-C水平明显高于CON组(Ps0.05),给药4周后,AOE组TC、LDL-C水平均显著性降低(Ps0.05)。高通量测序结果显示,AOE组中与脂质代谢、多聚糖生物合成与代谢相关的肠道菌群多样性及丰度增加显著,肠道菌群的生态环境得以改善,形成了新的肠道菌群稳态。结论泽泻醇提取物可以有效降低高脂高糖饮食大鼠的血脂水平,对其肝脏具有保护作用。泽泻醇提取物也能通过改变肠道菌群的丰度、多样性和功能类群等靶标进行脂质代谢调节。     

江山乌猪肠道黏膜菌群组成及其功能的性别差异

肠道黏膜微生物在调控宿主生理功能方面发挥重要作用,其结构组成受到多种因素影响。性别被认为是塑造肠道微生物的因素之一。然而,性别对肠道黏膜菌群的差异影响还不清楚。【目的】以江山乌猪为研究对象,探究性别差异对其肠道黏膜微生物组成及功能的影响。【方法】选取性成熟的雌性和雄性江山乌猪各8头,利用16S rRNA基因高通量测序技术分析回肠和结肠黏膜菌群。【结果】在回肠黏膜中,雄性江山乌猪菌群的Chao1指数和Shannon指数显著高于雌性(P<0.05),在结肠黏膜中,不同性别江山乌猪菌群Chao1指数和Shannon指数无显著差异(P>0.05)。菌群差异分析显示,回肠黏膜中,沙雷氏菌属(Serratia)和埃希氏志贺菌属(Escherichia_Shigella)在雌性组中的相对丰度显著高于雄性组(P<0.05),雄性组中Oscillospiraceae UCG-005、拟普雷沃氏菌属(Alloprevotella)、布劳特氏菌属(Blautia)和Prevotellaceae_NK3B31_group相对丰度显著高于雌性组(P<0.05);结肠黏膜中,雌性组中unclassified_Muribaculaceae、Rikenellaceae_RC9_gut_group和Prevotellaceae UCG-003相对丰度显著高于雄性组(P<0.05),Oscillospiraceae UCG-005、Lachnospiraceae_NK4A136_group和unclassified_Lachnospiraceae在雄性组中相对丰度更高(P<0.05)。功能预测发现,雄性乌猪回肠黏膜菌群显著富集了氨基酸代谢、碳水化合物代谢和能量代谢等功能途径(P<0.05);结肠黏膜菌群主要富集了膜转运相关的ABC转运蛋白和信号转导相关的双组分系统等功能途径(P<0.05)。【结论】不同性别江山乌猪肠黏膜菌群结构及功能具有明显差异。这些结果揭示了不同性别江山乌猪肠道黏膜菌群的差异特征,为了解和挖掘我国地方畜禽品种肠道微生物资源提供部分参考。     

一株植物乳杆菌Lp3对高脂模型大鼠的益生作用

【目的】本研究通过构建大鼠高脂结构模型来探究一株植物乳杆菌Lp3的益生作用。【方法】植物乳杆菌Lp3筛选自青藏高原地区传统发酵的牦牛酸奶,初步认定Lp3是一株具有良好耐受力的降胆固醇菌株,且体外益生特性突出,本研究通过建立高脂SD大鼠模型,在饲喂试验动物高脂饲料的同时灌胃植物乳杆菌Lp3,来确定该菌株对试验动物血脂的影响效果,并同时研究其对大鼠肠道菌群、粪便水分、粪便中胆固醇和胆汁酸含量的影响,以及对肝脏组织中的胆固醇(TC)和甘油三酯(TG)的影响。【结果】结果表明,植物乳杆菌Lp3对大鼠没有任何明显的毒副作用,对高脂模型大鼠具有良好的降血脂效果。饲喂高脂饲料并灌喂乳酸菌Lp3组大鼠(HL)的血清总胆固醇、甘油三酯和低密度脂蛋白胆固醇含量较饲喂高脂饲料组(HC)显著减少(P0.05),但是高密度脂蛋白胆固醇的含量变化并不明显。HC组大鼠与HL组及饲喂普通日粮组(对照组)大鼠相比较,HC组大鼠粪便中大肠杆菌数量明显增加,双歧杆菌、乳杆菌数量明显减少。但是灌胃乳酸菌的HL组大鼠的粪便中乳杆菌数略高于对照组,大肠杆菌和双歧杆菌数量和对照组大鼠的基本一致。表明植物乳杆菌Lp3具有维持肠道菌群平衡的作用。此外灌胃乳酸菌后HL组大鼠粪便含水量比HC组要高6.44%。HC组大鼠肝脏组织中胆固醇和甘油三酯要显著高于HL组(P0.05),说明Lp3可以减少脂类物质在肝脏组织中的沉积。从肝脏组织切片来看,也可以得出上述结论。【结论】结果表明本研究所筛选的植物乳杆菌Lp3对高脂大鼠具有值得深入研究的益生作用。     

基于肠道菌群和短链脂肪酸代谢探讨不同饮食条件下高脂血症大鼠发病机制

目的 本研究拟对比两种不同高脂饮食方式诱导的高脂血症大鼠肠道菌群变化与短链脂肪酸代谢特征,以宿主-肠道菌群-代谢角度探讨高脂血症可能的微观机制。方法 SPF级SD大鼠分为：正常饮食组(CG组):饲喂大鼠维持饲料;高脂饮食组(HFD1组):每天足量饲喂高脂饲料;限饲高脂饮食组(HFD2组):每天限量饲喂高脂饲料80 g,不限量饲喂维持饲料。8周后检测血清总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)和高密度脂蛋白胆固醇(HDL-C)水平;苏木精-伊红(HE)染色观察大鼠肝组织和肾周脂肪病理学变化;取结肠内容物进行16S rDNA高通量测序,观察肠道菌群结构与功能的变化,并检测结肠内容物中短链脂肪酸的含量。结果 与CG组相比,HFD1组和HFD2组大鼠摄食量下降,体重升高;血清中TC、TG、LDL-C均显著升高;肝组织发生明显脂肪变性,肾周脂肪出现炎性病变;高脂干预后大鼠肠道菌群相对丰度显著变化,其中乳杆菌属相对丰度明显降低,菌群结构和功能变化明显,总短链脂肪酸、乙酸、丁酸、异丁酸下降显著。结论 两种高脂饮食方式均能引起大鼠高脂血症,且发病机制基本一致,均与脂质代谢以...     

微生物转化影响不同内源雌激素水平大鼠粪便雌马酚含量和菌群结构

雌马酚(Equol)是肠道中特定细菌转化大豆异黄酮的产物,与其前体大豆苷元(Daidzein)相比,雌马酚具有更强的生物学活性。【目的】研究口服雌马酚产生菌对大鼠转化大豆苷元能力的可能促进作用及内源雌激素对大鼠肠道菌群的可能影响。【方法】使用平均体重为211±9g的卵巢摘除和假手术雌性大鼠各30只,分别随机分为5组,并灌胃蒸馏水、雌二醇、大豆苷元、雌马酚和大豆苷元+雌马酚产生菌ZX7。【结果】从灌胃第2天开始,接受大豆苷元后大鼠粪样中始终具有较高水平的雌马酚,显著高于对照和雌二醇组(P<0.01);灌胃大豆苷元+雌马酚产生菌ZX7的大鼠和直接灌胃雌马酚的大鼠在粪样雌马酚含量上十分接近;DGGE图谱的PCA分析显示,卵巢摘除大鼠和假手术大鼠粪便菌群存在明显差异;大鼠粪便拟杆菌门细菌数量与粪样中雌马酚水平显著正相关。【结论】大鼠肠道固有菌群中可能存在能够将大豆苷元转化为雌马酚的细菌,利用外源菌株改变大鼠雌马酚产生能力具有一定的可行性,不同的内源雌激素水平可能影响大鼠肠道菌群结构,拟杆菌门细菌可能在大豆苷元的生物转化过程中起着十分重要的作用。     

野生蓝莓和花青素提取物对高脂饮食小鼠肠道菌群的影响

【目的】研究野生蓝莓和花青素提取物对高脂饮食小鼠肠道菌群的影响。【方法】采用高脂饲料喂养C57BL/6小鼠,同时膳食补充野生蓝莓或花青素提取物,将25只无菌小鼠分为5组:正常对照组(Normal chow diet,NCD),普通饲料+10 g/100 g蓝莓组(NCD+BB),高脂饲料组(High-fat diet,HFD),高脂饲料+10 g/100 g蓝莓组(HFD+BB),高脂饲料+20 mg/100 g花青素组(HFD+ACN),饲养10周,每周对其食物摄入量、能量摄入量以及体重进行测定,并运用DGGE方法对小鼠肠道菌群结构变化进行动态监测。【结果】各实验组食物摄入量无显著性差异,HFD+BB组和HFD+ACN组能量摄入量均明显高于NCD+BB组。虽然HFD+BB组体重增加最为明显,但10周末时HFD+BB组体重与其他各组无显著差异。随着实验的进行,HFD组、HFD+BB组和HFD+ACN组肠道微生物多样性发生明显变化。HFD+BB组与NCD组菌群差异最大,HFD+ACN组与NCD组肠道菌群DGGE图谱相似性系数明显高于HFD组,对优势条带测序结果显示膳食补充蓝莓或花青素提取物可明显降低肥胖相关细菌Firmicutes的数量。【结论】蓝莓和花青素提取物可改善由高脂饮食引起的肠道微生态失调,调节肠道菌群结构,具有潜在的减肥消脂功能。     

Definitions,measurements, and classifications of stimuli,situations, and environments

A review is presented of issues relevant to the definition, measurement, and classification of stimuli, situations, and environments. Problems such as the lack of adequate definitions of concepts, error and bias in measurement procedures, confusion between measurement of a concept and measurement of its behavioral effects, and the lack of agreement among alternative measures are emphasized. It is suggested that concepts be defined in terms of objective characteristics while allowing for the study of the transactional relationship between organism and environment. The work of the ethologists in defining stimuli while studying their relationship to different organismic states and situational contexts is emphasized in this regard. Following Brunswik, it is also suggested that wherever possible there be a representative sampling of variables in natural settings. Note from the editors: From time to time, Human Ecology will publish a review article. Our first in this series is a review by a psychologist of basic definitional and conceptual problems in environmental studies.This paper was prepared while the author was a Visiting Research Fellow at the Educational Testing Service. The support of ETS and my colleagues in the Division of Psychological Studies is gratefully acknowledged. The review was also supported in part by a grant from the Rutgers University Research Council.     

Synthesis,tautomerism, and antimicrobial,anti-HCV,anti-SSPE,antioxidant, and antitumor activities of arylazobenzosuberones

2-Dimethylaminomethylene-1-benzosuberone 1 was coupled with diazotized aniline derivatives to afford a series of the hitherto unreported 2-arylazo-1-benzosuberones 3a–i. The tautomeric structure and the effect of substituents on the tautomeric form (s) of the products 3a–i were discussed. Similar coupling of the enaminone 1 with diazonium salts of heterocyclic amines gave the respective fused azolotriazino-benzosuberones. Some of the newly synthesized compounds showed potent antimicrobial, anti-HCV, antioxidant, antitumor (as topoisomerase I inhibitors), and antimicrobial activities.     

Incorporating Science,Technology, Fairness,and Accountability in Environmental,Health, and Safety Decisions

The Precautionary Principle is in sharp political focus today because (1) the nature of scientific uncertainty is changing and (2) there is increasing pressure to base governmental action on more “rational” schemes, such as cost-benefit analysis and quantitative risk assessment, the former being an embodiment of ‘rational choice theory’ promoted by the Chicago school of law and economics. The Precautionary Principle has been criticized as being both too vague and too arbitrary to form a basis for rational decision making. The assumption underlying this criticism is that any scheme not based on cost-benefit analysis and risk assessment is both irrational and without secure foundation in either science or economics. This paper contests that view and makes explicit the rational tenets of the Precautionary Principle within an analytical framework as rigorous as uncertainties permit, and one that mirrors democratic values embodied in regulatory, compensatory, and common law. Unlike other formulations that reject risk assessment, this paper argues that risk assessment can be used within the formalism of tradeoff analysis—a more appropriate alternative to traditional cost-benefit analysis and one that satisfies the need for well-grounded public policy decision making. This paper will argue that the precautionary approach is the most appropriate basis for policy, even when large uncertainties do not exist, especially where the fairness of the distributions of costs and benefits of hazardous activities and products are a concern. Furthermore, it will offer an approach to making decisions within an analytic framework, based on equity and justice, to replace the economic paradigm of utilitarian cost-benefit analysis.     

Exercise, dobutamine, and combined atropine, norepinephrine, and epinephrine compared

We compared the cardiovascular effects evoked in conscious dogs by 1) submaximal exercise; 2) infusion of dobutamine (40 micrograms X kg-1 X min-1); and 3) infusion of a combination of atropine (0.15 mg/kg), norepinephrine (0.19 micrograms X kg-1 X min-1), and epinephrine (0.05 micrograms X kg-1 X min-1). Myocardial O2 demand, as estimated by the double product (heart rate X systolic blood pressure), was similar during all three interventions. Cardiac output and heart rate increased significantly (P less than 0.05) during each of the three interventions. Arteriovenous O2 difference and total body O2 consumption, however, increased only during submaximal exercise. Although myocardial blood flow increased similarly during each of the three interventions, blood flow to skeletal muscle and the tongue increased only during exercise. Exercise and the combined infusion of atropine, norepinephrine, and epinephrine produced similar increases in blood flow to the diaphragm and similar decreases in blood flow to the stomach. These changes in blood flow were associated with appropriate changes in vascular resistance. Additionally, blood flow to the brain, kidney, adrenal glands, liver, and intestine did not change during any of the three interventions. Thus, in dogs, submaximal exercise, infusion of dobutamine, and infusion of a combination of atropine, norepinephrine, and epinephrine to evoke a given level of estimated myocardial O2 consumption produce similar increases in cardiac output, heart rate, and myocardial blood flow. In contrast, the changes in total body O2 consumption, arteriovenous O2 difference, regional blood flow, and regional vascular resistance that occur during each of these three interventions are different.     

Indians, Markets, and Rainforests: Theory, Methods, and Analysis

Indians, Markets, and Rainforests: Theory, Methods, and Analysis. Ricardo A. Godoy. New York: Columbia University Press, 2001. 274 pp.     

Whales,lifespan, phospholipids,and cataracts

This study addresses the question: why do rats get cataracts at 2 years, dogs at 8 years, and whales do not develop cataracts for 200 years? Whale lens lipid phase transitions were compared with the phase transitions of other species that were recalculated. The major phospholipids of the whale lens were sphingolipids, mostly dihydrosphingomyelins with an average molar cholesterol/phospholipid ratio of 10. There was a linear correlation between the percentage of lens sphingolipid and lens lipid hydrocarbon chain order until about 60% sphingolipid. The percentage of lens sphingolipid correlated with the lens lipid phase transition temperature. The lifespan of the bowhead whale was the longest of the species measured and the percentage of whale lens sphingolipid fit well in the correlation between the percentage of lens sphingolipid and lifespan for many species. In conclusion, bowhead whale lens membranes have a high sphingolipid content that confers resistance to oxidation, allowing these lenses to stay clear relatively longer than many other species. The strong correlation between sphingolipid and lifespan may form a basis for future studies, which are needed because correlations do not infer cause. One could hope that if human lenses could be made to have a lipid composition similar to whales, like the bowhead, humans would not develop age-related cataracts for over 100 years.