双歧杆菌对小鼠溃疡性结肠炎模型的影响

目的：研究双歧杆菌对小鼠急性溃疡性结肠炎模型的影响。方法：葡聚糖硫酸钠（DSS）制备小鼠溃疡性结肠炎模型。应用实体显微镜观察整段大肠的粘膜改变情况;普通粪便涂片观察小鼠粪便中细菌的变化,梯度稀释法行粪便菌群分析,了解几种代表性的菌群的改变;一般病理切片,行HE染色,观察镜下病理变化,结果：双歧杆菌 DSS组相比,血便不明显,镜下组织病理改变轻微,肠道菌群无明显紊乱。结论：双歧杆菌对溃疡性结肠炎发生有预防作用,并能减轻症状和病变。     

6-姜烯酚对溃疡性结肠炎小鼠结肠上皮细胞Notch信号通路的影响

目的:观察6-姜烯酚对溃疡性结肠炎小鼠结肠上皮细胞Notch信号通路的调控作用。方法:清洁级昆明小鼠40只随机分为正常组(10只)和造模组(30只),造模组采用2%葡聚糖硫酸钠(DSS)自由饮用诱导溃疡性结肠炎模型,造模15 d后分为模型组,6-姜烯酚组,阳性对照组,每组10只。正常组、模型组灌胃生理盐水,6-姜烯酚组采用6-姜烯酚100 mg/(kg·d)灌胃,阳性对照组采用柳氮磺吡啶100 mg/(kg·d)灌胃,给药20 d后处死,观察小鼠结肠病理组织学改变,免疫荧光双标法检测结肠上皮细胞Hes-1、Math-1蛋白的表达,RT-PCR法检测结肠上皮组织Notch-1、Hes-1、Math-1 mRNA的表达,Western blot法检测结肠上皮组织Notch-1、Hes-1、Math-1蛋白的表达。结果:与正常组相比,模型组小鼠结肠上皮组织Notch-1、Hes-1蛋白和mRNA相对表达量显著升高( P＜0.01), Math-1蛋白和mRNA相对表达量显著降低( P＜0.01);与模型组比较,6-姜烯酚组、柳氮磺吡啶组小鼠结肠上皮组织Notch-1、Hes-1蛋白和mRNA相对表达量显著降低( P＜0.01), Math-1蛋白和mRNA相对表达量显著升高( P＜0.01) 。结论:6-姜烯酚能够抑制Notch通路的过度活化,调节结肠上皮吸收细胞系和分泌细胞系之间分化的平衡,修复受损结肠粘膜组织。     

白藜芦醇对小鼠溃疡性结肠炎的影响*

目的:研究白藜芦醇通过调节Wnt/β-catenin信号通路抗溃疡性结肠炎的作用机制。方法:①葡聚糖硫酸钠盐(DSS)诱发溃疡性结肠炎实验:28只C57BL/6小鼠随机分为4组(n=7):control组、 DSS组、DSS+白藜芦醇(DSS+Res)组和Res组。实验周期为3周,小鼠饮用DSS水诱导溃疡性结肠炎并给予白藜芦醇灌胃。实验期间每天称小鼠体重并观察小鼠活动和粪便情况。处理结束后,安乐死小鼠,取小鼠脾脏称重,取小鼠结肠测量长度。苏木精-伊红染色法(H&E)染色观察小鼠结肠组织病理改变;实时荧光定量PCR(qPCR)检测小鼠结肠组织miRNA-31的表达;Western Blot检测小鼠结肠组织β-catenin、Cyclin D1蛋白的表达。②离体实验:以10 mg/ml浓度的白藜芦醇处理HCT 116细胞,检测HCT 116细胞β-catenin、低密度脂蛋白受体相关蛋白6(LRP-6)、卷曲蛋白3(FZD3)、c-Myc蛋白的表达;HCT 116细胞转染miRNA-31 mimic和inhibitor,检测β-catenin蛋白的表达。结果:①DSS组小鼠实验期间体重下降明显,精神萎靡,活动减少,出现血便;处理结束后小鼠的结肠长度缩短,脾脏增大。而给予白藜芦醇后小鼠的以上情况得到改善。②白藜芦醇抑制了溃疡性结肠炎小鼠结肠组织miRNA-31的表达及β-catenin、Cyclin D1蛋白的表达。③白藜芦醇下调HCT 116细胞β-catenin、LRP-6、FZD3、c-Myc蛋白的表达。转染miRNA-31 inhibitor后,HCT 116细胞中β-catenin蛋白表达减少。结论:白藜芦醇能够抑制DSS诱导的小鼠溃疡性结肠炎,这种作用与下调Wnt信号通路有关,其对Wnt 信号的下调作用与miRNA-31有关。     

低聚果糖对溃疡性结肠炎模型小鼠肠黏膜屏障影响的研究

目的 探讨低聚果糖对溃疡性结肠炎（UC）模型小鼠肠黏膜屏障的调节作用及可能机制。方法 小鼠随机分成3组：正常对照（NC）组、模型（MD）组和低聚果糖（FOS）组,采用葡聚糖硫酸钠制作UC小鼠模型。造模7 d同时给予干预治疗,停用造模药物并后续治疗7 d。采用细菌定量测定法检测肠道菌群,放射免疫法检测肠黏膜sIgA,ELISA法检测小鼠肠黏膜IL-10、TNF-α和IL-6水平。结果 模型组小鼠存在肠道菌群失调（t=2.088,2.036,2.203,2.109,P<0.05）,其TNF-α、IL-6水平高于正常对照组（t=1.734,1.801,P<0.05）,肠黏膜sIgA、IL-10低于正常对照组（t=1.820,1.806,P<0.05）;低聚果糖组肠道菌群失调状况较模型组有所改善,其TNF-α、IL-6水平低于正常对照组（t=1.980,1.816,1.936,1.920,1.969,1.893,P<0.05）,肠黏膜sIgA、IL-10高于正常对照组（t=1.801,1.796,P<0.05）。结论 低聚果糖可改善溃疡性结肠炎模型小鼠肠道菌群屏障功能,可以提高肠黏膜sIgA和抗炎细胞因子IL-10的水平并降低致炎细胞因子TNF-α和IL-6的水平,通过调节肠道过度的免疫反应,使免疫屏障功能得到一定恢复。     

核桃低聚肽对急性溃疡性结肠炎小鼠的改善作用

目的：探讨核桃低聚肽（WOPs）对急性溃疡性结肠炎小鼠的改善作用。方法：成年雄性BALB/C小鼠按体重随机分为6组,空白对照组、模型对照组和3个WOPs剂量组（220、440、880 mg/kg BW）,每组10只。小鼠饮用5%DSS构建急性溃疡性结肠炎模型,灌胃给予相应受试物7 d,每日观察测量DAI。7 d后,处死小鼠测量结肠外观形态及长度变化、CMDI,血清DAO、D-LA含量,结肠组织TNF-α、IL-1β、IL-6、IL-10、MPO含量,并进行结肠组织病理学观察。结果：WOPs能显著减少血清DAO和D-LA含量,降低DAI评分、结肠组织MPO、IL-1β、IL-6、TNF-α水平,提高IL-10水平,明显增加结肠长度,降低CMDI。此外,WOPs还可以恢复DSS所致的结肠黏膜炎症损伤。结论：WOPs对经DSS诱导的溃疡性结肠炎小鼠具有改善作用,其机制可能与调整机体内促炎因子与抗炎因子含量有关。     

小鼠溃疡性结肠炎模型的建立及病理组织学比较

目的建立乙酸,右旋葡聚糖硫酸钠（dextran sodium sulfate,DSS）,幽门螺杆菌（Helicobacter pyliri）小鼠溃疡性结肠炎（ulcerative colitis）动物模型,通过病理学对比观察,选择最佳的小鼠溃疡性结肠炎动物模型。方法将40只清洁级BALB/c小鼠随机分为4组,实验组中Ⅰ组采用乙酸刺激法诱发溃疡性结肠炎,Ⅱ组采用饮用3.5%DSS溶液诱发结肠炎,Ⅲ组采用幽门螺杆菌感染小鼠诱发溃疡性结肠炎,对照组饮用蒸馏水。观察小鼠每日的体重,大便性状和隐血情况,以及结肠大体形态和组织病理学改变。结果乙酸,右旋葡聚糖硫酸钠均可引起小鼠疡性结肠炎。结论 DSS诱发的小鼠溃疡性结肠炎是一种较理想的UC动物模型,可作为研究UC发病机制和药物治疗较理想的工具。     

参苓白术散对溃疡性结肠炎模型小鼠的疗效评价

目的 探究参苓白术散对葡聚糖硫酸钠(DSS)诱导的溃疡性结肠炎(UC)模型小鼠的疗效.方法 选用雄性BALB/c小鼠(6～8周龄,18～20 g)36只,随机分成6组,每组6只.A组:参苓白术散高剂量组;B组:参苓白术散中剂量组;C组:参苓白术散低剂量组;D组:柳氮磺胺吡啶治疗组;E组:空白对照组;F组:模型组.以连续...     

乳杆菌对急性溃疡性结肠炎模型小鼠的疗效观察

目的观察植物乳杆菌YXCC-1和嗜酸乳杆菌YXCC-2对小鼠急性溃疡性结肠炎(UC)的疗效。方法对这两株菌进行体外模拟胃肠环境抗性研究,并进行动物实验。采用DSS诱导的小鼠急性UC模型,将60只小鼠随机分为4组,分别为空白对照组、DSS模型组、YXCC-1组和YXCC-2组,每组15只,观察小鼠治疗前后一般情况,计算小鼠组织学损伤评分以及观察组织学病理改变。结果菌株YXCC-1、YXCC-2有一定的耐酸、耐胆盐能力,在人工肠液环境下能较好存活;灌胃菌株发酵液可显著降低UC小鼠DAI水平,明显改善结肠组织损伤。结论植物乳杆菌YXCC-1、嗜酸乳杆菌YXCC-2发酵液对小鼠溃疡性结肠炎有治疗作用,且两者疗效相当。     

恶唑酮诱导BALB/C小鼠溃疡性结肠炎的实验研究

目的:探讨恶唑酮诱导小鼠溃疡性结肠炎(UC)模型的建立,并评估其在UC研究中的价值.方法:30只BALB/C小鼠被随机分成模型组、对照组和治疗组,每组10只.予恶唑酮建模后,治疗组给予柳氮磺胺吡啶灌胃治疗,观察三组小鼠的疾病活动指数(DAI).一周后处死所有小鼠,取其病变结肠观察组织学改变,并检测脾组织重量,采用酶联免疫吸附法(ELISA)测定三组小鼠血清白细胞介素IL-10、IL-2的含量.结果:模型组小鼠病变结肠组织学改变与人类UC病变结肠形态相似,其DAI和组织学损伤评分均较对照组有明显改变.血清IL-10含量显著增高,IL-2含量明显下降,免疫脏器脾脏的重量明显减轻.结论:恶唑酮能诱导出与人类UC发病相似的实验小鼠模型.可作为研究UC病因、发病机制和药物治疗较为理想的模型.     

NLRP3敲除小鼠溃疡性结肠炎模型的建立与分析

目的 采用不同浓度DSS及给药时间诱导NLRP3^-/-小鼠溃疡性结肠炎(ulcerative colitis, UC)模型,并分析与评价其优劣性,为UC发病机制的研究和治疗药物研发提供更贴切临床的动物模型。方法 SPF级48只雄性NLRP3^-/-小鼠随机分组,每组12只小鼠(空白组、2.5%7 d组、3%7 d组和3%5 d组),采用不同浓度DSS和给药时间相结合诱导UC小鼠模型,观察和评价小鼠的体重、DAI评分、HE染色、结肠长度及相关指标(IL-6、TNF-α和紧密连接蛋白(ZO-1))的表达水平评价造模的效果。结果 (1)DSS各小组在不同浓度及给药时间均能诱导UC模型;(2)随着浓度梯度增加及给药时间延长,NLRP3^-/-小鼠的体重减轻越显著、粪便潜血呈阳性越明显、DAI评分越高,甚者出现死亡;(3)经HE染色发现,NLRP3^-/-小鼠肠黏膜屏障组织病理损伤随DSS给药时间增长或浓度增高而加重;(4)采用免疫组织化学方法检测炎症因子及紧密连接蛋白,相对于空白组、模型组的炎症因子(TNF-α及...     

Effects of oral supplement of L-glutamine on diverted colon wall

Diverted colorectal segments can present trophic and inflammatory changes. These alterations are of special importance in the patients whose colostomy becomes permanent, as well as in the differential diagnosis with other inflammatory diseases. This study was accomplished to quantify these alterations and to determine if oral supplement of L-glutamine would avoid them. Twenty-six adult male Wistar rats were distributed in three groups: control, colostomized and colostomized+L-glutamine. The colostomized group received a loop colostomy. The colostomized+L-glutamine group received a colostomy similar to the previous group and oral supplement of L-glutamine. Partial volumes of all layers of the colonic wall were measured by image analysis stereology. The diversion caused a decrease of partial volumes of the mucosa and the epithelium as well, and also of the height of the intestinal crypts ( p <0.05). There was an increase of partial volumes of the lamina propria, of the submucosa and of the muscularis mucosae vs controls ( p <0.05). The partial volume of the muscularis propria didn't show significant alteration. The supplementation of L-glutamine was effective in preventing the atrophy of mucosa and epithelium ( p <0.05), also avoiding the increase of partial volumes of the submucosa and lamina propria ( p <0.05). This supplement didn't change significantly the muscular layers. In conclusion, colostomy causes the atrophy of the colon wall, mainly due to the atrophy of the epithelium. The supplementation of L-glutamine is able to avoid these changes.     

Effects of supplementation with free glutamine and the dipeptide alanyl‐glutamine on parameters of muscle damage and inflammation in rats submitted to prolonged exercise

In this study, we investigated the effect of the supplementation with the dipeptide L ‐alanyl‐L ‐glutamine (DIP) and a solution containing L ‐glutamine and L ‐alanine on plasma levels markers of muscle damage and levels of pro‐inflammatory cytokines and glutamine metabolism in rats submitted to prolonged exercise. Rats were submitted to sessions of swim training for 6 weeks. Twenty‐one days prior to euthanasia, the animals were supplemented with DIP (n = 8) (1.5 g.kg^?1), a solution of free L ‐glutamine (1 g.kg^?1) and free L ‐alanine (0.61 g.kg^?1) (G&A, n = 8) or water (control (CON), n = 8). Animals were killed at rest before (R), after prolonged exercise (PE—2 h of exercise). Plasma concentrations of glutamine, glutamate, tumour necrosis factor‐α (TNF‐α), prostaglandin E2 (PGE2) and activity of creatine kinase (CK), lactate dehydrogenase (LDH) and muscle concentrations of glutamine and glutamate were measured. The concentrations of plasma TNF‐α, PGE2 and the activity of CK were lower in the G&A‐R and DIP‐R groups, compared to the CON‐R. Glutamine in plasma (p < 0.04) and soleus muscle (p < 0.001) was higher in the DIP‐R and G&A‐R groups relative to the CON‐R group. G&A‐PE and DIP‐PE groups exhibited lower concentrations of plasma PGE2 (p < 0.05) and TNF‐α (p < 0.05), and higher concentrations of glutamine and glutamate in soleus (p < 0.001) and gastrocnemius muscles (p < 0.05) relative to the CON‐PE group. We concluded that supplementation with free L ‐glutamine and the dipeptide LL ‐alanyl‐LL ‐glutamine represents an effective source of glutamine, which may attenuate inflammation biomarkers after periods of training and plasma levels of CK and the inflammatory response induced by prolonged exercise. Copyright © 2009 John Wiley & Sons, Ltd.     

Effects of medium glutamine,glutamate, and ammonia on glutamine synthetase activity in cultured mouse astroglial cells

Mouse astroglial cells were grown during the last week of culture in either glutamine-free or glutamine-containing medium. The addition of cortisol to the glutamine-containing medium resulted in a doubling of astroglial glutamine synthetase (GS) activity. Withdrawal of glutamine from the medium resulted in a 50% elevation of GS and addition of cortisol to such a medium resulted in a further increase in GS which was not additive to glutamine withdrawal. Both in glutamine-free and glutamine-containing medium, the addition of glutamate resulted in a depression of both basal and cortisol induced GS activity. The simultaneous addition of ammonia plus glutamate to the culture medium ameliorated the glutamate mediated depressive effects on cortisol induced but not basal GS activity. Glutamine withdrawal from the culture medium resulted in an astroglial protein deficit. The addition of ammonia to the medium considerably reduced this deficit and the addition of glutamate completely eliminated this protein deficit.     

氯化两面针碱对小鼠溃疡性结肠炎的干预作用及其机制*

目的:探讨氯化两面针碱(NC)通过靶向miR-31对葡聚糖硫酸钠(DSS)诱发小鼠结肠炎的保护作用及其机制。方法:用1%DSS诱发小鼠溃疡性结肠炎(UC)。30只雄性C57BL/6小鼠随机分为正常对照组(Control)(n=7),DSS组(n=8),DSS+NC组(7.27 mg/kg)(n=8)和NC组(n=7),饮水给予DSS,灌胃给予氯化两面针碱。造模周期为3周,分别为Control组和NC组每天饮用无菌水,DSS组和DSS+NC组第一周饮用1% DSS水,第2周正常饮水,第3周1% DSS水。造模最后一周给予Control组和DSS组小鼠0.5% 羧甲基纤维素钠(CMC-Na)灌胃,DSS+NC组和NC组给予NC灌胃。造模完成后,观察小鼠结肠炎相关的疾病活动指数(DAI),HE染色进行结肠组织病理评分,qPCR检测小鼠结肠组织miR-31的表达水平,Western blot检测小鼠结肠组织炎症蛋白NF-κB和COX-2的表达情况。结果:①与DSS组相比,DSS+NC组的 DAI 显著降低(P＜0.01),结肠病理损伤明显改善;②与Control组相比,DSS组小鼠结肠组织miR-31表达显著升高(P＜0.01),DSS+NC组miR-31的表达水平显著低于DSS组(P＜0.05);③与DSS组相比,DSS+NC组中的炎症蛋白NF-κB和COX-2表达水平显著下降(P＜0.05)。结论:氯化两面针碱对DSS诱导的小鼠溃疡性结肠炎有明显的治疗作用,其抗炎机制与下调miR-31的表达有关。     

Effects of glutamine and asparagine on recombinant antibody production using CHO‐GS cell lines

A unique and nontraditional approach using glutamine and asparagine supplements for CHO‐glutamine synthetase (GS) cell lines was studied. In our experiments, we found that a decrease in pH and an increase in cell death occurred in production phase of a GS cell line, leading to reduced antibody expression and lower antibody yields. The experimental results and the statistical analysis (ANOVA) indicated that additions of glutamine and asparagine in the basal and feed media were effective to buffer the cell culture pH, reduce lactate generation, maintain a higher cell viability profile, and improve antibody productivity. In bench‐top bioreactors, glutamine and asparagine supplementation helped to prevent cell death, improve antibody yield, and reduce base usage. Glutamine is normally excluded from culture media for GS cell lines to prevent the bypass of selection pressure. In this study, however, the addition of glutamine did not affect cell population homogeneity, protein quality, or decrease antibody yield of two GS cell lines. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:1457–1468, 2014     

Mulberry juice freeze-dried powder attenuates the disease severity by the maintaining of colon mucosa in mice with DSS-induced acute colitis

This study aimed to evaluate the microbial compositions and gene expression related to inflammation in dextran sodium sulfate (DSS)-induced acute colitis and the effect of mulberry supplementation. Male BALB/c mice received a diet supplemented with mulberry juice freeze-dried powder (MFP) or not for 3 weeks. After 3 weeks, the mice received water containing 5% (w/v) DSS or not for 1 week. The disease activity index score in mice fed MFP was significantly decreased. A significant decrease in Bifidobacterium spp. and the Clostridium perfringens subgroup was observed in mice not fed MFP. The number of goblet cell and NLRP6 expression were observed in mice fed a diet supplemented with MFP compared with mice not fed MFP. These results may indicate that mulberry mitigates DSS-induced acute colitis by a changing the gut microbial flora and by improving mucosal conditions.     

整肠生对溃疡性结肠炎小鼠肠上皮屏障的保护作用

目的 探讨整肠生对溃疡性结肠炎小鼠肠道紧密连接蛋白表达以及对氧化应激反应的影响。方法 选用雄性8~10周龄C57BL/6小鼠40只,随机分为4组：对照组、模型组（3% DSS）、5-ASA组（3% DSS+5-ASA 200 mg/kg灌胃）和整肠生组（3% DSS+联合整肠生及5-ASA灌胃）,每组10只,造模7 d。观察各组小鼠便血程度、组织学损伤情况,通过投射电镜观察各组肠道上皮间紧密连接改变情况,应用Western blot和RT-PCR的方法,检测小鼠结肠黏膜紧密连接蛋白Occludin、ZO-1、Claudin-2的表达情况。结果 （1）与模型组比较,5-ASA组和整肠生组小鼠便血程度明显减轻,DAI评分显著降低（P<0.05）。整肠生组与5-ASA组比较,便血减轻,DAI评分降低（P<0.05）。（2）电镜显示,对照组肠上皮间紧密连接呈一条致密条带,结构完整,见细胞桥粒,微绒毛光滑、排列整齐,细胞间隙狭窄;模型组肠上皮间紧密连接结构松散、模糊、密度降低,桥粒结构消失,微绒毛稀疏,短缩且长短不一,细胞间隙增宽;各治疗组的紧密连接的破坏情况较模型组有不同程度的改善,整肠生组紧密连接清晰,细胞间隙缩窄,微绒毛排列整齐,出现细胞桥粒。（3）应用Western blot和Real time-PCR法检测,与正常组相比,模型组Occludin、ZO-1蛋白和mRNA表达显著下降,Claudin-2表达显著上调（P<0.05）;各治疗组较模型组Occludin、ZO-1蛋白表达上调,Claudin-2蛋白表达下调（P<0.05）,整肠生组较单用5-ASA组更明显提高Occludin、ZO-1蛋白和mRNA表达。（4）与正常组相比,模型组MDA含量增高,SOD活性降低,与5-ASA组相比,整肠生组能更显著地降低MDA含量,提高SOD活性（P<0.05）。结论 联合应用整肠生通过调节紧密连接蛋白Occludin、ZO-1的表达和降低氧化应激反应,来改善溃疡性结肠炎小鼠肠上皮屏障功能。     

一株猪肠道Lactobacillus animalis LGM对结肠炎小鼠Th细胞分化转录因子基因表达的影响

【目的】从体外和体内研究Lactobacillus animalis LGM对Th细胞分化转录因子T-bet、GATA-3、ROR-γt和Foxp3的调节作用,以及探究L. animalis LGM对小鼠结肠炎的影响。【方法】本试验采用改良型的Hungate滚管技术从猪结肠内容物中分离一株L. animalis LGM,根据其16S rRNA序列进行鉴定。收集L. animalis LGM培养液上清,与细菌脂多糖(LPS,2μg/mL)同时孵育Caco-2细胞24 h,体外研究L. animalis LGM对Caco-2细胞内Th细胞分化转录因子(T-bet,GATA3,ROR-γt和Foxp3) mRNA表达的影响;配制L. animalis LGM细菌悬液,研究L. animalis LGM灌胃对DSS诱导结肠炎小鼠症状及结肠Th细胞分化转录因子和细胞因子(IFN-γ,IL-4,IL-17和IL-10) mRNA表达的影响,表达结果采用荧光定量PCR法检测。【结果】与对照组相比,L.animalisLGM培养液上清显著上调Caco-2细胞内ROR-γt与Foxp3 mRNA表达(P0.05),显著下调GATA3、IL-4、IL-17和TGF-βmRNA表达(P0.05)。L. animalis LGM灌胃显著上调小鼠结肠内ROR-γt和Foxp3的表达(P0.05),显著降低了促炎因子IL-4和IL-17的表达(P0.05),阻止了小鼠结肠长度缩短(P0.05)。【结论】猪肠道分离L. animalis LGM表现出对Th细胞分化转录因子的选择性调节,显著上调Caco-2细胞及结肠炎小鼠ROR-γt与Foxp3mRNA表达。降低DSS诱导结肠炎小鼠炎症水平,对DSS诱导结肠炎起保护作用,有助于维护肠道环境稳态。