新疆昆仑雪菊水提物对小鼠肠道菌群的调节作用

目的 研究新疆昆仑雪菊水提物对小鼠肠道菌群的影响。方法 C57BL/6小鼠,雄性,8周龄,40只,分为4个组（每组10只）：高、中、低三个剂量组和空白对照组,给药14 d,收集给药前后小鼠粪样,16S rDNA实时荧光定量PCR法测定粪样中肠杆菌、肠球菌、乳杆菌和产气荚膜梭菌水平。结果 与空白对照组比较,中剂量组小鼠肠道粪样中乳杆菌显著增多（t=‒2.503,P<0.05）,低剂量组与高剂量组变化不显著;与空白对照组比较,其他组小鼠肠道中肠杆菌属、肠球菌属和产气荚膜梭菌水平均无显著变化。结论 参照《保健食品检验与评价技术规范—2003版》之“调节肠道菌群作用检验方法”,新疆昆仑雪菊水提物对小鼠肠道菌群具有一定的调节作用。     

气相色谱法测定猪结肠内容物中短链脂肪酸含量

目的:为了准确测定猪结肠内容物中蛋白质代谢物短链脂肪酸含量以研究猪结肠蛋白质代谢情况,本文拟利用气相色谱建立一种更准确快速分析猪结肠内容物中短链脂肪酸含量的方法。方法:实验选用体重相近的21日龄断奶的杜长大三元杂交仔猪,单栏饲养。试猪麻醉后放血致死,迅速剖开腹腔,收集结肠末端内容物,保存于-80℃。收集到的结肠末端内容物用偏磷酸预处理,利用毛细管气相色谱法程序升温测定猪结肠内容物中短链脂肪酸含量。结果:结肠内容物经偏磷酸预处理3 h后,在程序升温、0.8 m L/min载气流量的气相色谱条件下,内容物中乙酸、丙酸、异丁酸、丁酸、异戊酸和戊酸得到有效分离,其回收率为93%~113%,相对标准偏差为0.46%~0.70%,变异系数小于1%。结论:此方法具有操作简便、快速、准确的优点,是测定动物肠道内容物中短链脂肪酸较为理想的方法。     

老年小鼠肠道短链脂肪酸含量和菌群特征关联性探究

随着社会经济的发展,我国人口老龄化日益严重,衰老这个永恒的问题又一次引起人们的关注.肠道菌群失衡是衰老发生发展的关键因素,而短链脂肪酸(short chain fatty acids,SCFAs)是介导菌群影响机体的主要方式之一.研究衰老、肠道菌群及SCFAs三者之间的关系,能够为临床通过干预肠道菌群影响SCFAs含量...     

健脾益肾通络方对MPTP诱导的帕金森病小鼠肠道菌群与短链脂肪酸的调节作用

探讨健脾益肾通络方（JYTR）对1-甲基-4-苯基-1,2,3,6-四氢吡啶（MPTP）诱导的帕金森病小鼠肠道菌群组成和短链脂肪酸的影响。

将成年雄性C57BL/6小鼠随机分成3组：空白组、MPTP组、MPTP+JYTR组,每组15只。采用爬杆、悬挂、横梁实验评估运动情况。采用免疫荧光法检测纹状体酪氨酸羟化酶（TH）的表达。采用蛋白印迹法检测纹状体和结肠中α-突触核蛋白（α-syn）的表达。采用16S核糖体RNA（16S rRNA）基因测序评估肠道菌群的变化。采用气相色谱质谱法（GC-MS）分析小鼠粪便短链脂肪酸的水平。最后对差异菌群和短链脂肪酸进行相关性分析。

与MPTP组相比,MPTP+JYTR组小鼠悬挂评分增加（P=0.040）,爬杆时间和横梁行走时间显著缩短（P=0.042、P＜0.001）;纹状体TH表达显著增加（P=0.045）,纹状体、结肠中α-syn表达显著减少（P=0.011、P=0.037）;肠道菌群alpha多样性、beta多样性显著改变;门水平方面拟杆菌门丰度增加（P=0.003）,厚壁菌门、疣微菌门丰度均显著减少（P=0.001、P=0.011）;科水平方面毛螺菌科丰度显著升高（P=0.001）,嗜黏蛋白阿克曼菌科、丹毒丝菌科丰度均显著降低（P=0.008、P=0.004）;短链脂肪酸中乙酸、丙酸水平均显著增加（P=0.014、P=0.010）。相关性分析显示爬杆时间、悬挂评分、横梁时间均与肠道菌群、短链脂肪酸存在相关性。

JYTR可以通过调节肠道菌群失调和改善短链脂肪酸水平起到治疗帕金森病的作用。

     

鸡肠道菌群和短链脂肪酸相互关系的研究进展

肠道是动物机体重要的消化和营养吸收器官。肠道菌群决定肠道健康,进而影响机体健康。近来关于肠道菌群的研究越来越多,且肠道菌群酵解底物产生的短链脂肪酸也备受人们关注。短链脂肪酸主要包括乙酸、丙酸、丁酸等及其盐类。在对肠道功效方面,短链脂肪酸发挥着重要作用,如氧化供能、维持水电解质平衡、调节免疫、抗病原微生物及抗炎、调节肠道菌群平衡、改善肠道功能等。因此,本文根据近年来国内外相关研究报道,综述了鸡肠道不同种类、含量的菌群对短链脂肪酸来源和吸收的影响;不同种类、含量和制剂形态的短链脂肪酸对肠道菌群影响的研究进展,为更好地了解鸡肠道菌群和短链脂肪酸的相互关系和提高禽类养殖水平提供理论指导。     

短链脂肪酸对肠道动力影响的研究进展

人体的肠道不仅仅是消化吸收场所,也是大量微生物生存的家园.肠道作为人体最大的储菌库,其多种生理功能离不开复杂多变的肠道菌群和菌群代谢物(如短链脂肪酸等)的参与.短链脂肪酸是肠道菌群发酵膳食纤维产生的一类重要的信号分子,研究发现短链脂肪酸除参与维持人体肠道黏膜免疫屏障、调节体液及电解质平衡以及为肠上皮细胞提供能量外,...     

鲍鱼内脏酶解物可调节肠道菌群及短链脂肪酸缓解小鼠系统低度炎症

为探究鲍鱼内脏酶解物对辣椒素诱导的系统低度炎症模型小鼠炎性因子、肠道菌群及短链脂肪酸的影响,将30只雄性小鼠随机分为6组：空白对照组、辣椒素致炎模型组、鱼油对照组、鲍鱼内脏酶解物低、中、高剂量组(0.30、0.60、1.20 g/(kg·d)),干预7 d后,ELISA法检测小鼠血清中肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、白细胞介素-10(IL-10),鲎试剂法测定小鼠血清中细菌脂多糖(LPS)的含量,16S rRNA基因高通量测序和生物信息学方法考察小鼠肠道菌群的结构组成,GC-MS法测定小鼠粪便中短链脂肪酸的含量。结果显示,辣椒素模型组小鼠血清中TNF-α、IL-6和LPS含量显著升高,肠道菌群OTUs数显著降低,菌群各门、属水平比例存在显著变化,其中寡养单胞菌属(Stenotrophomonas)和棒状杆菌属(Corynebactrium)等有害相对丰度显著增加,粪便中的乙酸、丙酸以及总短链脂肪酸含量显著降低,异戊酸含量显著升高,而经鲍鱼内脏酶解物干预后,小鼠血清中IL-1β、IL-6和LPS含量显著降低,肠道中乳杆菌属(La...     

短链脂肪酸在宿主能量代谢方面的调节作用

肠道菌群数量庞大,对宿主多种生理活动具有重要调节作用。现有研究发现,肠道菌群主要通过调节其产生的不同代谢产物,参与宿主物质代谢反应,改变能量代谢水平,影响机体炎症反应。在诸多代谢产物中,短链脂肪酸（醋酸盐、丙酸盐、丁酸盐等）具有重要调节作用,对机体代谢功能方面具有深远影响。本文结合国内外相关研究文献,综述了短链脂肪酸在调节机体能量代谢方面的相关研究,以期为进一步阐明其在机体能量代谢方面的作用提供科学依据。     

肠道短链脂肪酸与2型糖尿病相关性研究进展

2型糖尿病(type 2 diabetes,T2DM)是一种以高血糖为特征的代谢性疾病.随着经济的发展,人们的生活方式发生了巨大的变化,T2DM患者数量不断增加.T2DM的发病机制复杂,与遗传、环境、年龄、种族及生活方式等密切相关.近年来,许多研究表明肠道菌群通过多种途径参与T2DM的发生,其中短链脂肪酸起着主要作用....     

玉米须水提物对糖尿病大鼠肠道菌群的调节作用

目的考察玉米须水提物对糖尿病大鼠肠道菌群的调节作用,探讨其作用机制。方法利用高脂饲料联合链脲佐菌素诱导建立糖尿病大鼠模型,收集正常组、高脂组、模型组及给药组大鼠粪便,采用ERIC-PCR指纹图谱技术和气相色谱法分析不同组大鼠粪便的菌群多态性结构及短链脂肪酸含量的变化。结果 ERIC-PCR指纹图谱显示,正常组在250~750bp间显示两条特征条带,而高脂组与模型组则在100~250bp间出现多条特征条带,250~750bp间的条带变浅或消失,给药组的指纹图谱接近正常组;高脂组和模型组大鼠粪便的乙酸、丙酸、丁酸含量与正常组相比均显著下降(P0.05),模型组大鼠降低尤为显著,给药组三种短链脂肪酸含量相对于模型组及高脂组明显升高(P0.05)。结论玉米须水提物可能通过调节糖尿病大鼠肠道菌群的结构而使短链脂肪酸的含量增加进而发挥降糖作用。     

正常糖耐量个体粪菌液对db/db小鼠粪便短链脂肪酸的影响

通过气相色谱法检测经哈萨克族正常糖耐量人粪菌移植后的2型糖尿病db/db小鼠粪便中短链脂肪酸的含量,探讨肠道菌群代谢产物与糖尿病的关系。

db/db小鼠分为模型组（db/db+PBS组）和哈萨克族正常糖耐量人粪菌液干预组（db/db+KNGT组）,db/m小鼠为空白对照组（db/m+PBS组）,每组9只,干预10周。分别在干预0周、6周和10周后检测小鼠空腹血糖、低密度脂蛋白胆固醇、高密度脂蛋白胆固醇、总胆固醇和三酰甘油的水平,并收集各组小鼠粪便,运用气相色谱技术检测干预0周、6周和10周后小鼠粪便中短链脂肪酸的含量。

在哈萨克族正常糖耐量人粪菌液干预6周和10周后,与db/db+PBS组相比,db/db+KNGT组小鼠粪样中乙酸、丁酸的含量显著增加（F_乙酸 = 3.210,F_丁酸 = 8.530,均P＜0.05）。

哈萨克族正常糖耐量人粪菌液移植后小鼠粪样中菌群代谢产物乙酸和丁酸水平增加,从而改善了db/db小鼠的糖脂代谢紊乱。

     

基于气相色谱法分析T2DM患者粪便中SCFAs水平与HbA1c的相关性

目的 研究2型糖尿病患者粪便中6种短链脂肪酸水平与糖化血红蛋白的相关性。 方法 采用气相色谱法检测粪便中短链脂肪酸的含量,并对方法学进行考察。选取2018年在本院查体的2型糖尿病患者57例,根据糖化血红蛋白水平将其分为高糖化组(糖化血红蛋白>7.0,28例)与低糖化组(糖化血红蛋白≤7.0,29例)。应用气相色谱法检测两组患者粪便中6种短链脂肪酸水平,并分析6种短链脂肪酸水平与糖化血红蛋白的相关性。 结果 低糖化组患者粪便中乙酸、丙酸、丁酸、戊酸水平显著高于高糖化组(均P0.05)。Pearson相关性分析结果表明:在2型糖尿病患者中,糖化血红蛋白与粪便中乙酸呈负相关(r=-0.540 1,P结论 2型糖尿病患者粪便中短链脂肪酸水平与糖化血红蛋白存在一定的相关性,短链脂肪酸水平的下降可能是影响血糖控制不佳的主要原因。     

The absorption of calcium ions from the ovine reticulo-rumen

Net Ca²⁺ and Mg²⁺ absorption rates were measured in vivo from buffer solutions placed in the washed reticulo-rumen, isolated in situ in 30 conscious, trained sheep. An increase in concentration of short chain fatty acids (SCFA) in the buffer, over the range 0–50 mM, was shown to stimulate the net rates of absorption of Ca²⁺ and Mg²⁺ ions from the rumen. Similarly, the results of in vitro experiments, carried out with ovine rumen epithelium mounted in short-circuited Ussing chambers, showed that the absence of SCFA from the chamber fluid resulted in a reduction in J_net Ca²⁺ caused by reduced flux of Ca²⁺ ions in the mucosal to serosal direction (J_ms Ca²⁺). The addition of 1 mM acetazolamide, an inhibitor of carbonic anhydrase, to the ruminal buffer used in the in vivo experiments led to significant reductions in the net absorption rates of Ca²⁺and Mg²⁺ ions in the presence of SCFA (50 mmol l⁻¹) but not in the absence of SCFA. However, in the in vitro experiments, the addition of 60 μM ethoxyzolamide had no significant effect on J_net Ca²⁺. A reduction in pH of the intraruminal buffer in vivo from 6.8 to 5.4 led to significant increases in the net absorption rates of Ca²⁺and Mg²⁺ ions, an effect which was duplicated for Ca²⁺ in preliminary in vitro experiments in which the pH of the mucosal buffer was reduced from 7.4 to 5.4. This stimulatory effect was confined to J_ms Ca²⁺ and J_net Ca²⁺. Ussing chambers were also used to demonstrate that J_net Ca²⁺ was reduced by a high transmural potential difference (PD), caused by voltage clamping, independently of the mucosal K⁺ concentration. Both unidirectional Ca²⁺ fluxes consisted of a PD-dependent and a K⁺-insensitive PD-independent component. The latter may be represented by a Ca²⁺/2H⁺ antiporter. It is postulated that SCFA, and to a lesser extent H₂CO₃, can stimulate J_ms Ca²⁺ by activation of an apical Ca²⁺/2H⁺ antiporter through the provision of protons within the ruminal epithelial cell. A mild reduction in ruminal pH may also lead to a similar stimulation of this putative electroneutral exchange. Accepted: 26 July 2000     

广叶绣球菌多糖对免疫低下小鼠肠道免疫功能的调节作用

通过研究广叶绣球菌多糖对免疫低下小鼠肠道菌群、细胞因子表达量及短链脂肪酸的影响,探究广叶绣球菌多糖的免疫作用机制。腹腔注射环磷酰胺构建免疫低下小鼠模型,将小鼠分为6组：正常对照组、模型组、广叶绣球菌多糖低、中、高剂量组以及阳性对照组,连续饲养30d后处死取样,HE染色观察小肠组织结构,酶联免疫吸附法测定小肠白细胞介素-6（IL-6）、IL-10、肿瘤坏死因子-α（TNF-α）、干扰素-γ（IFN-γ）的表达水平,高通量测序技术分析小鼠肠道菌群的变化,气-质联用（GC-MS）技术分析盲肠内容物短链脂肪酸（SCFAs）的含量。结果表明,广叶绣球菌多糖高剂量组可显著改善绒毛肿胀和变短现象,提高绒毛长度/隐窝深度的比值（V/C值）和小肠IL-6、IL-10、TNF-α、IFN-γ细胞因子含量（P<0.05或P<0.01）,提高拟杆菌属Bacteroides、拟普雷沃菌属Alloprevotella、丁酸弧菌属Butyrivibrio、Intestinimonas、链球菌属Streptococcus的相对丰度（P<0.05或P<0.01）;各剂量组均可提高盲肠内6种主要短链脂肪酸含量,差异达显著或极显著水平（P<0.05或P<0.01）。试验组与阳性对照组趋势一致。广叶绣球菌多糖可通过改善免疫低下小鼠的肠道粘膜形态,提高小肠细胞因子水平,调节肠道菌群结构,增加SCFAs产生菌的相对丰度,提高短链脂肪酸含量,调节免疫低下小鼠的肠道免疫功能。     

Suppressive effect of short-chain fatty acids on production of proinflammatory mediators by neutrophils

Short chain fatty acids (SCFAs) are fermentation products of anaerobic bacteria. More than just being an important energy source for intestinal epithelial cells, these compounds are modulators of leukocyte function and potential targets for the development of new drugs. The aim of this study was to evaluate the effects of SCFAs (acetate, propionate and butyrate) on production of nitric oxide (NO) and proinflammatory cytokines [tumor necrosis factor α (TNF-α) and cytokine-induced neutrophil chemoattractant-2 (CINC-2αβ)] by rat neutrophils. The involvement of nuclear factor κB (NF-κB) and histone deacetylase (HDAC) was examined. The effect of butyrate was also investigated in vivo after oral administration of tributyrin (a pro-drug of butyrate). Propionate and butyrate diminished TNF-α, CINC-2αβ and NO production by LPS-stimulated neutrophils. We also observed that these fatty acids inhibit HDAC activity and NF-κB activation, which might be involved in the attenuation of the LPS response. Products of cyclooxygenase and 5-lipoxygenase are not involved in the effects of SCFAs as indicated by the results obtained with the inhibitors of these enzymes. The recruitment of neutrophils to the peritonium after intraperitoneal administration of a glycogen solution (1%) and the ex vivo production of cytokines and NO by neutrophils were attenuated in rats that previously received tributyrin. These results argue that this triglyceride may be effective in the treatment of inflammatory conditions.     

In vitro studies on active calcium absorption from ovine rumen

From various in vivo and in vitro studies it has been shown that the rumen represents a significant site of Ca²⁺ absorption in sheep and goats. It was the aim of the present study to further characterize the underlying mechanisms. Unidirectional flux rates of Ca²⁺ across rumen wall epithelia of sheep were measured in vitro by applying the Ussing-chamber technique in the absence of electrochemical gradients. Under these conditions, significant Ca²⁺ net flux rates (J_net) clearly indicate the presence of active mechanisms for Ca²⁺ transport. Short chain fatty acids (SCFAs) caused highest stimulation of Ca²⁺ J_net (6.3 ± 1.9 nmol · cm⁻² · h⁻¹) when used as a mixture of acetate, proprionate and butyrate in physiological proportions (36, 15, 9 mmol · l⁻¹, respectively). The effect of 30 mmol · l⁻¹ butyrate (3.2 ± 0.6 nmol · cm⁻² · h⁻¹) was higher than respective amounts of propionate and acetate (0.6 ± 0.8 nmol · cm⁻² · h⁻¹ and 0.9 ± 0.8 nmol · cm⁻² · h⁻¹, respectively). Eliminating SCFAs resulted in Ca²⁺ J_net of 0.4 ± 1.1 nmol ^. cm^−2 .h⁻¹. Addition of Ca channel blocker verapamil (mucosal 1 mmol · l⁻¹) had no significant effect on SCFA-stimulated J_net of Ca²⁺, whereas application of Na⁺/H⁺ inhibitor amiloride (mucosal 1 mmol · l⁻¹) further enhanced the Ca²⁺ J_net by >65%. The Ca²⁺-pump inhibitor vanadate had no significant effect on J_net of Ca²⁺. Dietary Ca depletion enhanced calcitriol plasma concentrations but had no effect on active Ca²⁺ absorption across the rumen wall of sheep. In addition, no effect on active Ca²⁺ absorption could be observed during early lactation. In conclusion, there is clear evidence for the rumen as a main site for active Ca²⁺ absorption in sheep. Our results suggest the presence of a Ca²⁺/H⁺ exchange mechanism in the apical membrane of rumen epithelial cells which depends on SCFA absorption and which does not seem to be under the control of calcitriol. Basolateral Ca²⁺ extrusion occurs independently from Ca²⁺-pump activity and may be accomplished via Na⁺/Ca²⁺ exchange. Accepted: 29 June 1999     

小鼠肠道菌群代谢产物与糖尿病的相关性研究

目的研究糖尿病小鼠粪便中肠道菌群代谢产物与血糖之间的相关性,探讨肠道菌群与糖尿病之间的关系。方法采用高脂饮料喂养加腹腔注射链脲佐菌素(STZ)的方法建立糖尿病小鼠模型;将实验动物随机分为正常组、高脂组、糖尿病组及模型给药组,连续给药5周后,采血测血糖血脂,同步收集动物粪便,测粪便中短链脂肪酸(Short-chain fatty acids,SCFA)及D-乳酸。SCFA的检测使用气相色谱法,D-乳酸的检测使用紫外酶促法。结果糖尿病组小鼠粪便中乙酸、丙酸和正丁酸含量明显低于正常组及高脂组(P<0.01),D-乳酸含量明显高于正常组及高脂组(P<0.01);给药组乙酸、丙酸和正丁酸含量明显高于糖尿病组(P<0.01),D-乳酸含量明显低于糖尿病组(P<0.01)。给药组丙酸、正丁酸的含量与正常组间差异无统计学意义(P>0.05),但乙酸的含量仍低于正常组(P<0.01),D-乳酸的含量仍高于正常组(P<0.01)。结论糖尿病小鼠粪便中的肠道菌群代谢产物与血糖之间存在着密切的关系,代谢产物的差异性,提示肠道菌群的差异性,反映出糖尿病小鼠存在肠道菌群紊乱。