植物性发酵乳杆菌对免疫系统的生理活性、抗高血糖和促进肠蠕动的影响

研究植物源性发酵乳杆菌对免疫系统生理活性、抗高血糖和促进肠蠕动的影响.β-内啡肽对免疫系统有重要作用,阿片-促黑素细胞皮质素原(POMC)是β-内啡肽的前体物质,为了探讨发酵乳杆菌对免疫功能的影响,检测小鼠下丘脑和脑垂体中POMC的基因表达水平.通过喂食发酵乳杆菌时间和浓度的不同及测量β一内啡肽表达水平的方式,来分析血液中B-内啡肽的变化情况.此外,测定了三种小鼠模型的血糖变化,即常规的WT小鼠模型、D-葡萄糖诱导的急性高血糖模型和链唑霉素(STZ)诱导的糖尿病模型,以证实发酵乳杆菌的降血糖效果,并对降血糖效果进行了验证.通过检测血糖随喂食发酵乳杆菌浓度和时间而变化的情况,已证实给药浓度和时间对血糖浓度有很好的影响.另外,为证实发酵乳杆菌对肠蠕动的影响测定了胃肠通过时间,证明发酵乳杆菌对肠蠕动有极好的促进作用.通过此项研究,证实发酵乳杆菌对提高人体免疫系统的生理活性、抗高血糖和促进小肠蠕动有极佳的效果.     

砂仁对抗生素所致肠道菌群失调小鼠调节作用的探讨

【摘要】 目的 通过建立抗生素诱导小鼠肠道菌群失调模型,应用PCR-变性梯度凝胶电泳(PCR-DGGE)技术分析小鼠肠道菌群失调前后经服用中药砂仁调理后肠道菌群指纹图谱的变化。方法 选用10只昆明种小鼠,正常培养7 d,适应环境后每天取粪便1次,连续3 d;菌群稳定后按100 mg/kg的头孢拉啶灌胃,每天灌胃2次,连续5 d,每天取粪便1次;上述小鼠随机分为两个组,自然恢复组(饲喂基础饲料)和砂仁处理组,每组5只。3 d后每天取粪便1次,连续3 d,提取细菌总DNA,以16S rRNA基因V3区通用引物扩增,对扩增的PCR产物进行DGGE电泳及指纹图谱分析并切胶测序比对。结果 抗生素处理后小鼠肠道菌群与正常小鼠差异有统计学意义,致病菌增加,砂仁处理组小鼠与正常小鼠的肠道菌群指纹图谱有很大的相似性,但与自然恢复组差异有统计学意义。结论 抗生素可导致小鼠肠道菌群失调,而中药砂仁对肠道菌群失调有明显的恢复作用。     

肠道微生物群落与炎症性肠病关系研究进展

目的炎症性肠病（IBD）包括克罗恩病（CD）和溃疡性结肠炎（UC）,以持续性肠道非特异性炎症为特征,通常反复发作、迁延不愈,临床上仍无特效性的治疗手段。IBD确切的发病机制尚不清楚,涉及免疫、环境及遗传等因素,这些因素共同诱导肠道炎症、黏膜损伤和修复。肠道微生物群落及其代谢产物、宿主基因易感性及肠道黏膜免疫三方面共同参与了IBD的发病机制。本文从消化道微生态角度出发,对目前IBD相关的肠道微生物群落研究现状、宿主-微生物间免疫应答及益生菌治疗等内容进行探讨。     

双歧杆菌四联活菌片对肝硬化白发性细菌性腹膜炎患者肠黏膜屏障和炎症因子的影响

目的探讨双歧杆菌四联活菌片对肝硬化自发性细菌性腹膜炎（SBP）患者肠黏膜屏障和炎症因子的影响。方法选择乙肝后肝硬化SBP患者68例,分为治疗组和对照组。两组患者均予以低盐饮食、护肝利尿、补充白蛋白和抗感染等基础治疗。治疗组在此基础上予以双歧杆菌四联活菌片口服,1．5g／次,3次／d,连用6周。结果治疗6周后,两组血浆内毒素、PCT和尿L／M比值比较均有明显下降（对照组比较P〈0．05,或治疗组比较P〈0．01）,且治疗组下降幅度明显优于对照组（P〈0．05）;两组血浆TNF-α、IL-6和IL-10水平均有明显下降（对照组比较P〈0．05,或治疗组比较P〈0．01）,且治疗组下降幅度明显优于对照组（P〈0．05）。治疗组临床总有效率明显高于对照组（χ2=8．17,P〈0．01）,治疗期间未发生严重的药物不良反应。结论双歧杆菌四联活菌片治疗肝硬化SBP患者具有较好的临床疗效及安全性,对患者肠黏膜屏障功能具有良好保护和改善作用,并能下降血浆TNF—α、IL-6和IL-10水平,具有辅助治疗肝硬化作用。     

消化道屏障与树突状细胞免疫研究进展

肠相关淋巴组织在防御病毒、细菌、寄生虫等有害物质入侵中发挥着重要作用,是消化道屏障的组成部分,其中肠道树突状细胞尤为重要,作为目前所知的机体内功能最强的专职性抗原呈递细胞,在肠道内,树突状细胞不但能对病原菌产生免疫应答,还能对肠腔内的正常菌群和各种食物蛋白产生免疫耐受,因此了解树突状细胞的功能及相关作用机制有着重要意义.现就对树突状细胞的生物学特性,以及其在肠道免疫中的作用进行综述.     

肠道菌群与疾病发生及中草药调节和治疗作用的研究概述

肠道正常菌群及微生态稳定对人体极具重要性,中草药对肠道菌群具有调节作用.本文综述了人体的肠道正常菌群与疾病产生和发展的关系,结合中草药对肠道菌群调节作用的研究,探讨中药调节肠道菌群与其发挥疾病防治效果之间的相关性,以期为中草药的临床应用及药理学研究提供一定的参考依据.     

感染华支睾吸虫大鼠肠道菌群的实验研究

目的 观察华支睾吸虫感染对大鼠肠道菌群的影响.方法 建立华支睾吸虫感染大鼠模型,分别在造模后48 h、18d和35 d,取肠内容物进行乳酸杆菌、双歧杆菌、肠球菌和肠杆菌的培养及定量分析.结果 与对照组相比,在感染后48 h,大鼠肠道乳酸杆菌和双歧杆菌数量减少(P＜0.05),肠球菌和肠杆菌数量略有增加,但差异无统计学意义(P＞0.05);在感染后18 d(童虫期),乳酸杆菌、双歧杆菌数量进一步减少(P＜0.01),肠杆菌和肠球菌数量明显增加(P＜0.01);在感染后35 d(成虫期),四种肠道菌与童虫期的变化基本一致.结论 华支睾吸虫感染可致大鼠肠道菌群发生失调,其中益生菌减少,致病菌增多,尤以童虫期、成虫期较重.     

慢性胃炎肠化生CD_(44)、CD_(44V6)及Cyclin D_1、Cyclin E的表达和意义

目的探讨慢性胃炎胃粘膜肠化生CD44、CD44V6及cyclin D1、Cyclin E表达的意义。方法利用免疫细胞化学技术对39例伴有肠化生的慢性胃炎和5例正常人胃窦粘膜的活检组织进行检查。结果正常人胃窦粘膜上皮,腺上皮对CD44、CD44V6、Cyclin D1和Cyclin E均为阴性,但在有神经内分泌样细胞的粘膜,CD44V6和cyclin D1为阳性。慢性胃炎肠化生区和不典型增生区除CD44为阴性外,CD44V6、cyclin D1和cyclin E均呈现不同的阳性反应,但未见有阳性的神经内分泌样细胞。间质细胞大都呈阳性反应。结论CD44V6、cyclin D1和cyclin E可能是胃癌前状态的早期事件,而CD44可能为胃癌晚期的标志物。     

Cloning and characterization of a new intestinal inflammation-associated colonic epithelial Ste20-related protein kinase isoform

Intestinal epithelial cells respond to inflammatory extracellular stimuli by activating mitogen activated protein kinase (MAPK) signaling, which mediates numerous pathophysiological effects, including intestinal inflammation. Here, we show that a novel isoform of SPS1-related proline alanine-rich kinase (SPAK/STE20) is involved in this inflammatory signaling cascade. We cloned and characterized a SPAK isoform from inflamed colon tissue, and found that this SPAK isoform lacked the characteristic PAPA box and alphaF loop found in SPAK. Based on genomic sequence analysis the lack of PAPA box and alphaF loop in colonic SPAK isoform was the result of specific splicing that affect exon 1 and exon 7 of the SPAK gene. The SPAK isoform was found in inflamed and non-inflamed colon tissues as well as Caco2-BBE cells, but not in other tissues, such as liver, spleen, brain, prostate and kidney. In vitro analyses demonstrated that the SPAK isoform possessed serine/threonine kinase activity, which could be abolished by a substitution of isoleucine for the lysine at position 34 in the ATP-binding site of the catalytic domain. Treatment of Caco2-BBE cells with the pro-inflammatory cytokine, interferon γ, induced expression of the SPAK isoform. Over-expression of the SPAK isoform in Caco2-BBE cells led to nuclear translocation of an N-terminal fragment of the SPAK isoform, as well as activation of p38 MAP kinase signaling cascades and increased intestinal barrier permeability. These findings collectively suggest that pro-inflammatory cytokine signaling may induce expression of this novel SPAK isoform in intestinal epithelia, triggering the signaling cascades that govern intestinal inflammation.     

Interaction between Shaoyao–Gancao–Tang and a laxative with respect to alteration of paeoniflorin metabolism by intestinal bacteria in rats

Shaoyao-Gancao-Tang (SGT), a traditional Chinese herbal medicine (Kampo formulation) containing Shaoyao (Paeoniae Radix) and Gancao (Glycyrrhizae Radix), is co-administered with laxative sodium picosulfate as a premedication for relieving the pain accompanying colonoscopy. Paeoniflorin (PF), an active glycoside of SGT, is metabolized into the antispasmodic agent paeonimetabolin-I (PM-I) by intestinal bacteria after oral administration. The objective of the present study was to investigate whether the co-administered laxative (sodium picosulfate) influences the metabolism of PF to PM-I by intestinal bacteria. We found that the PF-metabolizing activity of intestinal bacteria in rat feces was significantly reduced to approximately 34% of initial levels by a single sodium picosulfate pretreatment and took approximately 6 days to recover. Repeated administration of SGT after the sodium picosulfate pretreatment significantly shortened the recovery period to around 2 days. Similar results were also observed for plasma PM-I concentration. Since PM-I has muscle relaxant activity, the present results suggest that repetitive administration of SGT after sodium picosulfate pretreatment might be useful to relieve the pain associated with colonoscopy.