气道上皮损伤后支气管上皮-肌纤维母细胞转分化及转化生长因子β1的调节作用

目的 观察支气管上皮细胞损伤后,细胞表型、超微结构、内皮素1(endothelin-1,ET-1)、转化生长因子β1(transforming growth factor-β1,TGF-β1)表达的动态变化以及TGF-β1 对支气管上皮-肌纤维母细胞转分化(epithelial-mesenchymal transition,EMT)的调节.方法 以多聚左旋精氨酸(PA)诱导支气管上皮16HBE-14o细胞损伤,观察损伤后细胞培养液ET-1、TOF-β1及乳酸脱氢酶(LDH)含量、细胞表型及超微结构的动态改变,ET-1对上皮细胞TGF-β1 分泌的调节以及TGF-β1 对EMT的促进作用.结果 PA造成16HBE-14o损伤,损伤后LDH、ET-1、TGF-β1 释放增多.上皮修复过程中,一过性出现少量肌动蛋白阳性的细长梭形细胞,胞浆内同时可见肌微丝及丰富的粗面内质网,梭形细胞周围可见新分泌的胶原纤维,发生EMT.50 μg/L TGF-β1 能促进损伤上皮细胞的EMT,TGF-β1中和抗体能完全阻断EMT.ET-1能刺激上皮细胞分泌TGF-β1,且为ET-1 A受体阻断剂-bq123完全阻断.结论 支气管上皮细胞损伤后ET-1、TGF-β1 表达上调,出现上皮-间充质转分化.TGF-β1 能通过自分泌、旁分泌作用促进EMT.ET-1可能通过上调上皮细胞TGF-β1 的表达参与EMT的调节.气道上皮损伤后上皮细胞的活化、EMT可能在支气管哮喘气道重塑中发挥重要作用.     

罗红霉素和地塞米松对支气管哮喘大鼠气道重塑中成肌纤维细胞的影响

目的 探讨成肌纤维细胞(myofibroblast,MF)在支气管哮喘(简称哮喘)气道重塑中的作用.观察罗红霉素对哮喘气道重塑的影响,并与地塞米松作对照.方法 SD大鼠40只,随机分为哮喘组(A组)、生理盐水对照组(C组)、地塞米松治疗组(D组)和罗红霉素治疗组(R组),每组10只.利用卵白蛋白(ovalbumin,OVA)/Al(OH).致敏与OVA雾化吸人激发建立大鼠哮喘模型.免疫组织化学测定肺组织中支气管上皮下MF的一平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)表达含量,并使用图象分析技术进行积分光密度(integral optical density,IOD)定量分析测定.光镜观察肺组织病理结构变化,图像分析软件分析,并测定肺内支气管总管壁厚度、内管壁厚度、平滑肌层厚度等指标.结果 免疫组织化学和图像分析结果:A组与C组相比,总管壁厚度、内管壁厚度、平滑肌层厚度显著增厚(P<0.01).D组和R组中的内管壁厚度、平滑肌层厚度与A组相比.均显著变薄(P<0.01).R组的总管壁厚度、内管壁厚度、平滑肌层厚度与D组相比差异无统计学意义.定量分析测定的IOD值显示A组支气管上皮下MF α-SMA表达含量较C组显著增加(P<0.01),D组和R组表达含量较A组均减少(P<0.05),R组表达含量与D组相比差异无统计学意义.相关分析结果:支气管上皮下MF α-SMA表达含量(用IOD值表示)和内管壁厚度呈正相关(r=0.913,P<0.01,n=40),和平滑肌层厚度也呈正相关(r=0.626.P<0.01,n=40).结论 MF在气道重塑形成中起重要作用.罗红霉索和地塞米松均可能通过抑制MF增殖和表达起到抗哮喘气道重塑作用.     

α-平滑肌肌动蛋白在高氧肺损伤中的表达变化及意义

目的 探讨高氧暴露下大鼠肺损伤中肌成纤维细胞表面标志α-平滑肌肌动蛋白(α -SMA)的表达变化及意义.方法 将64只3周龄SD大鼠按随机数字表法分为正常对照组(置于空气中,吸入氧浓度0.21)和高氧暴露组(置于玻璃氧舱中,95％氧),每组于高氧暴露1、7、14、21d随机处死8只大鼠.苏木素-伊红(HE)染色观察肺组织病理改变,免疫组化法观察α -SMA在肺组织中的表达与分布,蛋白质免疫印迹法( Western blotting)检测肺组织α-SMA表达.结果 HE染色发现,早期高氧肺损伤时肺组织以炎症水肿表现为主,后期则以间质纤维增生为主.免疫组化结果显示,正常对照组α -SMA在细支气管上皮、肺泡表面及肺泡间隔上表达极为微弱;高氧暴露后随时间的延长α-SMA在肺泡表面及肺泡间隔上表达逐渐增强,以21d时最为明显.Western blotting检测发现,与正常对照组相比,高氧暴露1d、7d时肺组织α-SMA表达无明显差异(1.02±0.12比1.00±0.13,1.05±0.14比0.99±0.12,均P＞0.05),高氧暴露14d、21d时α-SMA表达明显增强(1.27±0.21比1.05±0.15,2.26±0.28比1.05±0.14,P＜0.05和P＜0.01).结论 大鼠高氧暴露后随时间延长,α-SMA在肺组织中的表达逐渐升高,肺纤维化逐渐加重,说明肌成纤维细胞在肺组织纤维化重构过程中起重要作用.     

HIV-1 Protein gp120 Induces Mouse Lung Fibroblast-to-Myofibroblast Transdifferentiation via CXCR4 Activation

BackgroundIndividuals with HIV have ～2-fold increased risk of developing pulmonary fibrosis. The mechanism(s) by which this occurs has yet to be determined. HIV-1 protein gp120 activates CXCR4 in the lymphocyte, promoting a variety of intracellular signaling pathways including those common to TGFβ1 associated with lung fibroblast-to-myofibroblast transdifferentiation. We hypothesized that gp120 promotes pulmonary fibrotic changes via activation of CXCR4 in the lung fibroblast.MethodsMouse primary lung fibroblasts (PLFs) were cultured ± gp120, then analyzed for α-SMA expression and stress fiber formation. In parallel, PLFs were cultured ± gp120 ± AMD3100 (a CXCR4 antagonist), and α-SMA, pan and phospho-Akt, and total and phospho-MAPK (or ERK1/2) protein expression was quantified. Finally, lungs and PLFs from wild-type and HIV-1 transgenic mice were analyzed for hydroxyproline and α-SMA content.Resultsgp120 treatment increased α-SMA expression and myofibroblast differentiation in PLFs. gp120 treatment activated phosphorylation of ERK1/2, but not PI3K-Akt. Pretreatment with AMD3100 inhibited gp120-induced ERK1/2 phosphorylation and gp120-induced α-SMA expression. In parallel, there was a significant increase in hydroxyproline content in lungs from older HIV-1 transgenic mice and a >3-fold increase in α-SMA expression in PLFs isolated from HIV-1 transgenic mice.Conclusionsgp120 induces α-SMA expression and fibroblast-to-myofibroblast transdifferentiation by activating the CXCR4-ERK1/2 signaling pathway in mouse PLFs. Lungs of older HIV-1 transgenic mice contain higher hydroxyproline content and their PLFs have a striking increase in α-SMA expression. These results suggest a mechanism by which individuals with HIV are at increased risk of developing pulmonary fibrotic changes as they age.     

Muscular hamartoma of the breast

Summary A rare case of muscular hamartoma of the breast was presented. An electron microscopic study confirmed that the proliferating spindle cells were of smooth muscle cell origin.     

In vivo responses of macrophages and myofibroblasts in the healing following isoproterenol-induced myocardial injury in rats

To clarify the relation between macrophage and myofibroblast involvement in various myocardial diseases, the authors investigated the kinetics of these cells in the healing (scar tissue formation) following isoproterenol-induced myocardial injury in rats. Alphasmooth muscle actin (-SMA) expressing myofibroblasts were seen at the border of the affected area and appeared in the greatest numbers on days 3–7 post-injection, followed by a gradual decrease by day 35. The peak on day 3 was consistent with the timing of the highest proliferative activity of myofibroblasts. The number of ED1-positive macrophages began to increase as early as day 1, reaching a peak on day 3 within the injured myocardium. The expansion of EDI-positive macrophages preceded an increased number of -SMA-positive myofibroblasts suggesting that myofibroblast proliferation and activation may be mediated by factors released by ED1-positive mcrophages in response to myocardial injury. The number of ED2-positive tissue-fixed, resident macrophages gradually increased from day 3 post-injection, and peaked on day 14, but the number of ED2-positive macrophages was consistently fewer than that of ED1-positive macrophages during the 35 day-observation period after the injection. The labelling index of the ED2-positive cells was maximal on day 14, indicative of local proliferation of resident macrophages. In the healing process after myocardial injury, EDI-positive macrophages increase markedly in the early stages; ED2-positive macrophages appear later.     

Daikenchuto (Da-Jian-Zhong-Tang) ameliorates intestinal fibrosis by activating myofibroblast transient receptor potential ankyrin 1 channel

AIM To investigate the anti-fibrotic effects of the traditional oriental herbal medicine Daikenchuto(DKT) associated with transient receptor potential ankyrin 1(TRPA1) channels in intestinal myofibroblasts. METHODS Inflammatory and fibrotic changes were detected in a2,4,6-trinitrobenzenesulfonic acid(TNBS) chronic colitis model of wild-type and TRPA1-knockout(TRPA1-KO) mice via pathological staining and immunoblotting analysis.Ca~(2+) imaging experiments examined the effects of DKT and its components/ingredients on intestinal myofibroblast(In Myo Fib) cell TRPA1 channel function.Profibrotic factors and transforming growth factor (TGF) -β1-associated signaling were tested in an In Myo Fib cell line by q PCR and immunoblotting experiments.Samples from non-stenotic and stenotic regions of the intestines of patients with Crohn’s disease (CD) were used for pathological analysis. RESULTS Chronic treatment with TNBS caused more severe inflammation and fibrotic changes in TRPA1-KO than in wild-type mice.A one-week enema administration of DKT reduced fibrotic lesions in wild-type but not in TRPA1-KO mice.The active ingredients of DKT,i.e.,hydroxyα-sanshool and 6-shogaol,induced Ca~(2+) influxes in In Myo Fib,and this was antagonized by co-treatment with a selective TRPA1 channel blocker,HC-030031.DKT counteracted TGF-β1-induced expression of TypeⅠcollagen andα-smooth muscle actin (α-SMA) ,which were accompanied by a reduction in the phosphorylation of Smad-2 and p38-mitogen-activated protein kinase (p38-MAPK) and the expression of myocardin.Importantly,24-h incubation with a DKT active component Japanese Pepper increased the m RNA and protein expression levels of TRPA1 in In Myo Fibs,which in turn negatively regulated collagen synthesis.In the stenotic regions of the intestines of CD patients,TRPA1 expression was significantly enhanced.CONCLUSION The effects of DKT on the expression and activation of the TRPA1 channel could be advantageous for suppressing intestinal fibrosis,and benefit inflammatory bowel disease treatment.     

Chronic myelogenous leukemia cells convert to myofibroblasts in vitro: effect of vascular endothelial growth factor on development of the microenvironment

To elucidate the biological characteristics of chronic myelogenous leukemia (CML) cells, we observed morphological and functional changes of CML cells during primary long-term culture, in which their morphology changed to that of myofibroblasts with similar molecular characteristics to the parental CML cells including BCR-ABL fusion gene, and produced cytokines such as granulocyte colony-stimulating factor, interleukin-6, and vascular endothelial growth factor (VEGF)-A. When cultured on the CML-derived myofibroblasts, parental non-adherent CML cells significantly proliferated. When anti-VEGF-A-neutralizing antibody was added to the cultures, non-adherent CML cell proliferation was significantly inhibited. These observations indicate that CML cells can convert their morphology and function to adherent myofibroblasts, and produce a significant amount of cytokine to give a growth-promotion activity to CML cells.     

高氧致新生大鼠支气管肺发育不良肺成肌纤维细胞分布的变化及意义

目的 观察高氧致新生大鼠支气管肺发育不良(BPD)肺组织α-平滑肌肌动蛋白(α-SMA)表达及胶原的变化,探讨高氧致新生大鼠BPD的发生与成肌纤维细胞的内在联系.方法 将新生大鼠持续暴露在85%高氧环境中,在实验的1、3、7、14、21 d,取左肺组织固定、脱水、石蜡包埋、切片,用于肺组织病理变化观察及α-SMA表达的免疫组织化学检测;右肺-80℃冰冻,用于Ⅰ型胶原(ColⅠ)蛋白和mRNA表达检测.结果 新生大鼠长期高氧暴露可致肺泡简单化,肺泡数目减少,终末气腔扩张,次级隔数目减少,肺泡间隔显著增厚,出现纤维化.高氧暴露14和21 d时,α-SMA在肺泡间隔和肺泡表面表达显著增强,呈条素状分布;但空气组仅在次级间隔的顶端呈点状分布.随高氧暴露时间延长,Col Ⅰ表达增加,并且高氧组肺组织α-SMA表达与Col Ⅰ mRNA表达呈明显正相关(r=0.59,P< 0.05).结论 新生大鼠高氧暴露导致肺损伤符合早产儿BPD的病理改变,成肌纤维细胞分布紊乱可能在BPD的发病过程中起重要作用.     

先天性胫骨假关节（CPT）的超微结构

目的：深入了解先天性胫骨假关节（CPT）的病理变化、细菌类型及其病变来源。方法：取5例先天性胫骨假关节（CPT）标本中不同部位的组织20例,经固定、切片染色后置于透射电镜下进行观察。结果：（1）断端间组织及病变骨膜组织性质完全一样,均为致密纤维结缔组织,细胞成分多,主要为纤维母细胞、肌纤维母细胞及少量未分化细胞。（2）移行部位骨膜组织结构和病变处骨膜组织结构相似。（3）断端处骨质细胞稀少,部分骨细胞萎缩或坏死,部分骨细胞含有空泡,骨基质未见异常。（4）移行部位骨质未见明显异常表现。结论：（1）先天性胫骨假关节（CPT）是非神经起源的、而是起源于骨膜的一种细胞增生活跃的纤维增生性变;（2）肌纤维母细胞与CPT发病有关。