腹腔注射百草枯构建小鼠肺纤维化模型

目的:探讨百草枯一次性腹腔注射致小鼠肺纤维化的病理改变及半数致死剂量(LD50),进而制备肺纤维化病理改变稳定的百草枯中毒小鼠肺纤维化模型。方法:60只正常雌性C57BL/6J小鼠被随机分为6组,10只/组,分别为正常对照组及百草枯给药30、40、50、60和80 mg/kg组,所有小鼠于造模后28 d处死,取其左肺用于病理观察(HE染色),并计算LD50及各组肺纤维化Ashcroft评级。结果:至观察期28 d,小鼠一次性腹腔注射百草枯溶液的LD50为55.1923 mg/kg;各染毒组均出现不同程度的肺纤维化改变,且注射剂量越高,肺纤维化病变越严重,但早期死亡率亦越高。结论:一次性腹腔注射百草枯可制备小鼠肺纤维化模型,40和50 mg/kg为较合适的造模剂量。     

不同剂量甲泼尼龙对急性百草枯中毒大鼠早期肺损伤干预研究

目的:探讨不同剂量的甲泼尼龙(Methylprednisolone,MPS)对急性百草枯(paraquat,PQ)中毒大鼠早期肺损伤的疗效。方法:采用腹腔注射20%的PQ溶液制作大鼠急性PQ中毒的模型,随机均分为五组,正常对照组(A组)、染毒组(B组)、5mg/kg甲泼尼龙干预组(C组)、15mg/kg甲泼尼龙干预组(D组)、30mg/kg甲泼尼龙干预组(E组)。分三个不同时间点(24、72、168h)处死大鼠(每组每时间点6只)。观察各时间点大体标本,组织病理、肺系数和氧合指数。结果:光镜下肺组织病理学观察,与B组比较C、D、E组大鼠肺的病理学改变,肺泡腔内出血、渗出,炎性细胞浸润、肺泡隔炎性细胞浸润相对较轻,其中以C、E组减轻最为明显。在各组相同时间点肺系数:在三个时间点的值均比B组低(P<0.05),其中E组在24h、72h时间点上与C、D组有显著差异(P<0.05)。C、D、E组与B组的氧合指数的比较各个时间点上均与B组有差异(P<0.05),三组之间相互无明显差异。结论:本实验结果显示甲泼尼龙对急性百草枯中毒大鼠的肺损伤具有保护作用,且30mg/kg甲泼尼龙组要优于5mg/kg、15mg/kg甲泼尼龙组。     

百草枯中毒大鼠TNF-α、IL-10 的表达及大黄保护作用的研究

目的:观察大黄对急性百草枯中毒大鼠TNF-α、IL-10的干预作用,探讨其可能的作用机制。方法:90只SD大鼠随机分为生理盐水对照组(A组)、PQ(60 mg/kg)灌胃染毒组(B组)、生大黄(300mg/kg.d)干预组(C组),每组30只。中毒后6h、24h、72h分批处死存活的大鼠,并且检测大鼠血浆TNF-α、IL-10水平。结果:B组、C组TNF-α、IL-10水平在染毒后6h开始升高,72h达到高峰,与A组相比,差异有统计学意义(P<0.05、P<0.01),在相同时间点C组TNF-α和IL-10的表达低于B组,差异均有统计学意义(P<0.01)。B组、C组血浆TNF-α、IL-10水平与中毒时间呈显著正性相关关系(r=0.849,P<0.01;r=0.790,P<0.01;r=0.0.943,P<0.01;r=0.892,P<0.01)。结论:大黄能够通过降低百草枯中毒大鼠体内的TNF-α、IL-10水平,减轻百草枯对大鼠的损伤作用。     

硫化氢在急性百草枯中毒致大鼠肺损伤中的作用

目的阐明百草枯中毒致大鼠肺损伤时机体内源性H2S的变化,探讨硫化氢在急性百草枯中毒致大鼠肺损伤中的作用。方法按时间点将50只大鼠分为5组,同时染毒;选择对应时间点50只大鼠为对照组。分组检测肺组织中内源性H2S的含量,并及时处死大鼠,行肺组织损伤病理学评分。另外取大鼠40只分为4组,即空白对照组、染毒组、染毒+外源性H2S组、外源性H2S组,于12h后,检测肺组织中内源性H2S的含量,并及时处死大鼠,行肺组织损伤病理学评分。结果百草枯中毒致大鼠肺损伤在不同时间范围内,机体内源性H2S的含量差异有显著统计学意义(P0.01);与染毒组比较,染毒组+外源性H2S组肺损伤程度评分显著降低,差异具有显著统计学意义(P0.01)。结论百草枯致大鼠肺损伤过程中,内源性H2S的含量与肺损伤程度呈负相关;外源性H2S通过增加体内肺组织H2S的含量,抑制百草枯致肺损伤。。     

人脐带间充质干细胞对炎症性肠病小鼠模型的治疗作用

目的:探讨2种方式移植人脐带间充质干细胞(UCMSC)对TNBS诱导的炎症性肠病小鼠模型的治疗作用。方法:分离培养人UCMSC,并通过一次性腹腔注射TNBS制备炎症性肠病动物模型,采用尾静脉注射和腹腔注射2种方式移植人UCMSC进行治疗,4周后处死,观察动物的死亡率、体重改变及结肠炎症变化,并进行大体和病理评分。结果:与对照组相比,尾静脉和腹腔注射移植UCMSC组动物死亡率下降,体重恢复较早,结肠病变大体评分和病理评分均显著改善;2种方式移植组之间的评分无显著差异。结论:尾静脉和腹腔移植人UCMSC对TNBS诱导的炎症性肠病小鼠模型均有治疗作用。     

百草枯中毒大鼠TNF-a、IL-10的表达及大黄保护作用的研究

目的：观察大黄对急性百草枯中毒大鼠TNF-α、IL-10的干预作用,探讨其可能的作用机制。方法：90只SD大鼠随机分为生理盐水对照组（A组）、PQ（60 mg/kg）灌胃染毒组（B组）、生大黄（300mg/kg.d）干预组（C组）,每组30只。中毒后6h、24h、72h分批处死存活的大鼠,并且检测大鼠血浆TNF-α、IL-10水平。结果：B组、C组TNF-α、IL-10水平在染毒后6h开始升高,72h达到高峰,与A组相比,差异有统计学意义（P〈0.05、P〈0.01）,在相同时间点C组TNF-α和IL-10的表达低于B组,差异均有统计学意义（P〈0.01）。B组、C组血浆TNF-α、IL-10水平与中毒时间呈显著正性相关关系（r=0.849,P〈0.01;r=0.790,P〈0.01;r=0.0.943,P〈0.01;r=0.892,P〈0.01）。结论：大黄能够通过降低百草枯中毒大鼠体内的TNF-α、IL-10水平,减轻百草枯对大鼠的损伤作用     

不同剂量甲泼尼龙对急性百草枯中毒大鼠早期肺损伤干预研究

目的：探讨不同剂量的甲泼尼龙（Methylprednisolone,MPS）对急性百草枯（paraquat,PQ）中毒大鼠早期肺损伤的疗效。方法：采用腹腔注射20％的PQ溶液制作大鼠急性PQ中毒的模型,随机均分为五组,正常对照组（A组）、染毒组（B组）、5mg／kg甲泼尼龙干预组（C组）、15mg／kg甲泼尼龙干预组（D组）、30mg／kg甲泼尼龙干预组（E组）。分三个不同时间点（24、72、168h）处死大鼠（每组每时间点6只）。观察各时间点大体标本,组织病理、肺系数和氧合指数。结果：光镜下肺组织病理学观察,与B组比较C、D、E组大鼠肺的病理学改变,肺泡腔内出血、渗出,炎性细胞浸润、肺泡隔炎性细胞浸润相对较轻,其中以C、E组减轻最为明显。在各组相同时间点肺系数：在三个时间点的值均比B组低（P〈0．05）,其中E组在24h、72h时间点上与C、D组有显著差异（P〈0．05）。C、D、E组与B组的氧合指数的比较各个时间点上均与B组有差异（P〈0．05）,三组之间相互无明显差异。结论：本实验结果显示甲泼尼龙对急性百草枯中毒大鼠的肺损伤具有保护作用,且30mg／kg甲泼尼龙组要优于5mg／kg、15mg／kg甲泼尼龙组。     

腹腔一次注射法构建百草枯致小鼠肺间质纤维化模型

目的建立一种简便易行的百草枯(PQ)致肺间质纤维化动物模型。方法 33只C57BL/6J小鼠随机分为实验组(30只)和对照组(3只)。实验组腹腔一次性注射PQ 10 mg/kg,并于染毒后第2、5、7、14、28天处死小鼠,对照组腹腔注射生理盐水并于第28天处死。观察两组小鼠的一般情况、肺组织大体结构和肺组织病理学改变。结果实验组小鼠在染毒后2 h即出现中毒性改变,肺组织在第28天出现了明显的纤维化改变。结论腹腔一次性注射PQ能简便、可靠的构建出肺纤维化动物模型,可用于进一步研究PQ中毒所致的肺间质纤维化发病机制和治疗方法。     

敌草快中毒诱导小鼠急性肺损伤对IL-17表达的影响

目的观察敌草快中毒诱导小鼠急性肺损伤对IL17表达的影响。方法取健康雄性SD大鼠120只,按随机数字表法分为空白组、假手术组、中毒组,各40只。中毒组给予一次性腹腔注射20 mg/kg敌草快制备小鼠中毒模型,假手术组给予腹腔注射等剂量磷酸盐缓冲液造模,空白组未作任何处理。观察3组小鼠造模后6 h、24 h及72 h的死亡情况,并检测其肺组织干湿比重及肺泡灌洗液中IL-17表达情况。结果假手术组、空白组6 h、24 h及72 h均无小鼠死亡现象,而中毒组6 h、24 h及72 h小鼠死亡分别为2只、5只、2只,在24 h时死亡率达到高峰。假手术组、空白组6 h、24 h及72 h的小鼠肺组织干湿比重及肺泡灌洗液中IL-17表达均无明显变化;而中毒组小鼠各时段的肺组织干湿比重及肺泡灌洗液中IL-17表达明显增多,均高于空白组、假手术组(均P0.05),且在24 h时达到高峰。结论敌草快诱导小鼠急性肺损伤可促使IL-17分泌增多,因此推测下调IL-17的表达可以减少肺损伤。     

内质网应激及自噬参与百草枯中毒所致肺损伤

目的:探讨内质网应激及自噬在百草枯中毒所致大鼠肺脏损伤中的作用。方法:选取Wistar大鼠腹80只,腹腔注射百草枯(15 mg/kg)建立百草枯中毒肺脏损伤的动物模型。染毒后1、3、7、14、21 d处死动物取肺组织,采用HE染色和Van Gieson(V.G)染色观察大鼠肺脏损伤及纤维化情况,电镜观察Wistar大鼠肺脏胞浆空泡变、自噬体的形成以及肺脏损伤。Western-blot方法观察Wistar大鼠内质网应激相关蛋白(GRP94、Caspase-12和CHOP)和自噬相关蛋白(LC3-II、Beclin-1)的表达。结果:HE及V.G染色结果显示随中毒时间延长,百草枯中毒肺损伤及肺纤维化逐渐加重;电镜结果显示百草枯中毒肺脏发生胞浆空泡变、自噬体形成。与对照组比较,在百草枯中毒组内质网应激相关蛋白GRP94在3 d表达达到峰值(P0.001),7 d表达开始降低(P0.05),CHOP蛋白表达3 d开始增加(P0.001),cleaved caspase-12蛋白表达7 d开始增加(P0.001),并逐渐加强,自噬相关蛋白LC3-II和Beclin-1表达3 d开始增加(P0.001),14 d表达最高(P0.001)。结论:内质网应激以及细胞自噬共同参与百草枯中毒所致肺脏损伤。     

百草枯致急性肺损伤大鼠模型的建立

目的建立一种百草枯诱导的急性肺损伤（ALI）大鼠模型。方法将20只SD大鼠随机分为正常对照组10只、实验组10只。实验组一次性口服灌胃百草枯（PQ）80mg／kg,于给药后1天处死大鼠,观察光镜下肺组织病理改变、肺动脉血氧分压（PaO2）、支气管肺泡灌洗液（BALF）蛋白含量等。结果给予百草枯1天后肺形态学出现显著异常,PaO2及BALF蛋白含量出现显著改变。结论一次性灌胃百草枯80mg／kg成功建立急性肺损伤动物模型。     

甘草酸二铵对百草枯中毒致急性肺损伤大鼠TLR-4表达的影响

目的探讨甘草酸二铵(DG)对百草枯(PQ)中毒致急性肺损伤(ALI)大鼠的保护作用及其机制。方法选择健康SD大鼠50只,随机分为百草枯组(PQ组)、甘草酸二铵组(DG组)和正常对照组(NS组),PQ组和DG组予百草枯100mg/kg灌胃1次,DG组于灌胃后立即腹腔注射DG 50mg/kg,每日1次,对照组与PQ组注射等剂量的生理盐水。观察至48h处死大鼠,取肺组织检测肺湿干重比;肺组织HE染色评价肺组织损伤情况;采用RT-PCR法检测肺组织TLR-4mRNA和NF-κB mRNA的表达情况。另选择健康SD大鼠50只,分组及各组处置方法同上,观察其7天内死亡率。结果 PQ组与DG组肺湿干比、肺组织TLR-4mRNA和NF-κB mRNA表达较NS组明显升高(P0.01);DG组各指标明显低于PQ组(P0.01)。HE染色结果,NS组肺部结构正常,PQ组、DG组可见肺组织水肿、出血及炎性细胞浸润等肺损伤表现,DG组病变轻于PQ组。群体死亡率比较,PQ组7天死亡率为90%,DG组为40%,NS组无死亡。结论甘草酸二铵可减轻百草枯中毒致急性肺损伤大鼠肺部炎症,其机制可能与降低TLR-4、NF-κB的表达有关。     

Aging and lung injury repair: a role for bone marrow derived mesenchymal stem cells

The incidence of lung fibrosis increases with age. Aging is associated with modifications in the intracellular and extracellular environment including alteration of the extracellular matrix, imbalance of the redox state, accumulation of senescent cells and potential alteration of the recruitment of bone marrow mesenchymal stem cells. The combination of these senescence-related alterations in the lung and in bone marrow progenitor cells might be responsible of the higher susceptibility to lung fibrosis in elderly individuals. The understanding of these age related changes must be considered in the rationale for the development of therapeutic interventions to control lung injury and fibrosis.     

Allogeneic Human Mesenchymal Stem Cells Restore Epithelial Protein Permeability in Cultured Human Alveolar Type II Cells by Secretion of Angiopoietin-1

Acute lung injury is characterized by injury to the lung epithelium that leads to impaired resolution of pulmonary edema and also facilitates accumulation of protein-rich edema fluid and inflammatory cells in the distal airspaces of the lung. Recent in vivo and in vitro studies suggest that mesenchymal stem cells (MSC) may have therapeutic value for the treatment of acute lung injury. Here we tested the ability of human allogeneic mesenchymal stem cells to restore epithelial permeability to protein across primary cultures of polarized human alveolar epithelial type II cells after an inflammatory insult. Alveolar epithelial type II cells were grown on a Transwell plate with an air-liquid interface and injured by cytomix, a combination of IL-1β, TNFα, and IFNγ. Protein permeability measured by ¹³¹I-labeled albumin flux was increased by 5-fold over 24 h after cytokine-induced injury. Co-culture of human MSC restored type II cell epithelial permeability to protein to control levels. Using siRNA knockdown of potential paracrine soluble factors, we found that angiopoietin-1 secretion was responsible for this beneficial effect in part by preventing actin stress fiber formation and claudin 18 disorganization through suppression of NFκB activity. This study provides novel evidence for a beneficial effect of MSC on alveolar epithelial permeability to protein.     

Prevention of endotoxin-induced systemic response by bone marrow-derived mesenchymal stem cells in mice

Bone marrow-derived mesenchymal stem cells (BMDMSCs) appear to be important in repair of the chronic lung injury caused by bleomycin in mice. To determine effects of these BMDMSCs on an acute inflammatory response, we injected C57BL/6 mice intraperitoneally with 1 mg/kg endotoxin followed either by intravenous infusion of 5 x 10(5) BMDMSCs, the same number of lung fibroblasts, or an equal volume of normal saline solution. Lungs harvested 6, 24, and 48 h and 14 days after endotoxin showed that BMDMSC administration prevented endotoxin-induced lung inflammation, injury, and edema. Although we were able to detect donor cells in the lungs at 1 day after endotoxin, by 14 days no donor cells were detected. BMDMSC administration suppressed the endotoxin-induced increase in circulating proinflammatory cytokines without decreasing circulating levels of anti-inflammatory mediators. Ex vivo cocultures of BMDMSC and lung cells from endotoxemic animals demonstrated a bilateral conversation in which lung cells stimulated proliferation and migration of stem cells and suppressed proinflammatory cytokine production by lung cells. We conclude that BMDMSCs decrease both the systemic and local inflammatory responses induced by endotoxin. These effects do not require either lung engraftment or differentiation of the stem cells and are due at least in part to the production of stem cell chemoattractants by the lungs and to humoral and physical interactions between stem cells and lung cells. We speculate that mobilization of this population of BMDMSCs may be a general mechanism for modulating an acute inflammatory response.     

人脐带间充质干细胞在急性肾小管坏死模型犬的体内分布及趋化性

目的 观察人脐带间充质干细胞在家犬急性肾小管坏死模型的体内分布及归巢.方法 健康家犬18 只随机分为3 组.模型1 组:肌注新鲜配制的0.2﹪二氯化汞溶液7 ml/kg建立急性肾小管坏死模型,采用经外周静脉注射法输注体外分离培养并用4',6- 二脒基-2- 苯基吲哚(DAPI)标记的人脐带间充质干细胞.模型2 组:造模...     

Human Umbilical Cord Matrix Mesenchymal Stem Cells Suppress the Growth of Breast Cancer by Expression of Tumor Suppressor Genes

Human and rat umbilical cord matrix mesenchymal stem cells (UCMSC) possess the ability to control the growth of breast carcinoma cells. Comparative analyses of two types of UCMSC suggest that rat UCMSC-dependent growth regulation is significantly stronger than that of human UCMSC. Their different tumoricidal abilities were clarified by analyzing gene expression profiles in the two types of UCMSC. Microarray analysis revealed differential gene expression between untreated naïve UCMSC and those co-cultured with species-matched breast carcinoma cells. The analyses screened 17 differentially expressed genes that are commonly detected in both human and rat UCMSC. The comparison between the two sets of gene expression profiles identified two tumor suppressor genes, adipose-differentiation related protein (ADRP) and follistatin (FST), that were specifically up-regulated in rat UCMSC, but down-regulated in human UCMSC when they were co-cultured with the corresponding species’ breast carcinoma cells. Over-expression of FST, but not ADRP, in human UCMSC enhanced their ability to suppress the growth of MDA-231 cells. The growth of MDA-231 cells was also significantly lower when they were cultured in medium conditioned with FST, but not ADRP over-expressing human UCMSC. In the breast carcinoma lung metastasis model generated with MDA-231 cells, systemic treatment with FST-over-expressing human UCMSC significantly attenuated the tumor burden. These results suggest that FST may play an important role in exhibiting stronger tumoricidal ability in rat UCMSC than human UCMSC and also implies that human UCMSC can be transformed into stronger tumoricidal cells by enhancing tumor suppressor gene expression.