重组人核心蛋白多糖固相拮抗转化生长因子β1对瘢痕成纤维细胞的刺激作用

目的模拟人体内核心蛋白多糖和转化生长因子β1(TGF-β1)接触方式,观察核心蛋白多糖固相拮抗TGF-β1刺激瘢痕成纤维细胞的效果.方法制备成纤维细胞胶原网格(FPCL)体外三维培养模型,将其分为4组.对照组向FPCL中加入培养液;核心蛋白多糖组向FPCL中混入终浓度2 mg/L的重组人核心蛋白多糖,再加入培养液;TGF-β1组向FPCL中加入含5 μg/L TGF-β1的培养液;TGF-β1+核心蛋白多糖组向FPCL中混入终浓度2 mg/L的重组人核心蛋白多糖,然后加入含5μg/L TGF-β1的培养液.在培养12、24、48、72、96 h时观察各组FPCL的收缩情况,并用蛋白质印迹法与逆转录聚合酶链反应分别检测FPCL中瘢痕成纤维细胞Ⅰ型纤溶酶原激活物抑制因子1(PAI-1)、α平滑肌肌动蛋白(α-SMA)的蛋白及mRNA表达水平.结果各培养时相点下,TGF-β1组FPCL收缩比对照组明显增强,核心蛋白多糖组FPCL收缩则比对照组明显减弱.TGF-β1组的PAI-1、α-SMA的蛋白及相应mRNA表达水平(3 482±211、4 320±272;0.89±0.15、0.56±0.11)显著高于对照组(1 764±147、1 699±146;0.29±0.06、0.21±0.06,P＜0.01);其余两组相应检测指标与对照组比较差异无统计学意义(P＞0.05).结论重组人核心蛋白多糖混入胶原凝胶,可显著抑制TGF-β1对瘢痕成纤维细胞的刺激作用,表明在体外核心蛋白多糖具有拮抗TGF-β1的作用.提示皮肤组织损伤后,由于创面机械性缺少核心蛋白多糖,TGF-β1活性上调,可能是瘢痕增生的一个重要因素.     

RhoA/Rho激酶信号通路在TGF-β1诱导的人皮肤成纤维细胞表型转化中的作用

目的 观察TGF-[1对人皮肤成纤维细胞表型转化的作用是否受到RhoA/Rho激酶信号通路的影响,以探究该通路是否参与了人皮肤成纤维细胞的表型转化。方法 原代培养人皮肤成纤维细胞,将第4代细胞用TGF-β1( 10 ng/ml)刺激后,分不同作用时间(0、3、6、24h)提取细胞内总蛋白。BCA法测定总蛋白浓度,Western -blot检测α-SMA的表达水平;并用相同的方法检测不同浓度TGF-β1(0、2、10、50 ng/ml)刺激人皮肤成纤维细胞后,α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)的表达水平。用RhoA/Rho激酶信号通路阻断剂Y-27632处理后,再用TGF-β1刺激,作为实验组,将未作处理的正常细胞作为空白对照组,Y-27632（10 μmol/L）组作为阴性对照组,只用TGF-β1( 10 ng/ml)刺激组作为阳性对照组,分别检测α-SMA的表达差异。使用ANOVA对蛋白表达量进行统计学分析,P ＜0.05为差异有统计学意义。结果 10 ng/ml TGF-β1按不同作用时间刺激人皮肤成纤维细胞后,α-SMA的表达量分别为：0h为1.0,3h为1.9+0.2、6h为2.1±0.1,24 h为3.1±0.1。24 h较其他3个时间点α-SMA表达量明显上升（n=4,P＜0.05）。不同浓度TGF-β1刺激人皮肤成纤维细胞后,α-SMA的表达量分别为：0 ng/ml为1.0,2 ng/ml为1.4±0.2,10 ng/ml为3.2±0.1,50 ng/ml为3.1±0.2。10 ng/ml表达量明显高于0 ng/ml和2 ng/ml(n =4,P ＜0.05),较50 ng/ml差异无统计学意义(n=4,P＞0.05)。用Y-27632（10 μmol/L）处理后,再用TGF-β1刺激,细胞的表型转化明显受到抑制,实验组α-SMA的表达量(1.2±0.2)较阳性对照组(2.9±0.1)明显降低(n=5,P ＜0.05),与空白对照组(1.0)和阴性对照组(1.1±0.1)相比差异均无统计学意义(n=5,P＞0.05)。结论 RhoA/Rho激酶信号通路参与了 TGF-β1诱导的人皮肤成纤维细胞表型转化过程。     

血管内皮生长因子抑制肾小管上皮间充质转化及其与结缔组织生长因子和PI3K-Akt信号通路的关系

目的　探讨血管内皮生长因子（VEGF）对转化生长因子β1（TGF-β1）诱导的肾小管上皮间充质转化（EMT）的作用,及其与结缔组织生长因子（CTGF）、PI3K-Akt信号通路的关系。 方法 （1）将体外培养的HK2细胞分为正常对照组、TGF-β1（5 μg/L,下同）组、VEGF组（100 μg/L,下同）、TGF-β1＋VEGF组。HK2细胞体外培养48 h,用免疫组化双染方法检测肾小管上皮细胞α平滑肌肌动蛋白（α-SMA）和E钙黏蛋白的表达。（2）将体外培养的HK2细胞分为正常对照组、TGF-β1组、VEGF组、TGF-β1＋VEGF组、PI3K-Akt信号通路阻断剂LY294002组（25 μmol/L,下同）、TGF-β1＋LY294002组、VEGF＋LY294002组、TGF-β1＋VEGF＋LY294002组。HK2细胞体外培养48 h,用Western印迹和RT-PCR方法检测α-SMA和CTGF的表达;用ELISA方法检测培养上清中纤连蛋白（FN）和I型胶原（ColⅠ）的表达。 结果 免疫组化结果显示,TGF-β1组α-SMA表达比正常对照组增强,而E钙黏蛋白表达减弱; TGF-β1＋VEGF组α-SMA表达比TGF-β1组显著减弱,而E钙黏蛋白表达增强。 TGF-β1组α-SMA、CTGF蛋白和 mRNA及FN、ColⅠ表达比正常对照组显著增强（均P < 0.05）;TGF-β1＋VEGF组α-SMA、CTGF蛋白和mRNA及FN、ColⅠ表达比TGF-β1组显著减弱（均P < 0.05）;TGF-β1＋VEGF＋LY294002组α-SMA、CTGF蛋白和 mRNA及FN、ColⅠ表达比TGF-β1＋VEGF组显著增强（均P < 0.05）。 结论　VEGF能抑制TGF-β1诱导的体外培养的HK2细胞发生EMT,其机制可能与VEGF下调HK2细胞CTGF表达及减少细胞外FN、ColⅠ合成有关。VEGF的这种作用可能部分通过PI3K-Akt信号转导通路实现,其确切机制有待进一步研究。     

整合素连接激酶对瘢痕成纤维细胞VEGF的调控作用

目的 探讨整合素连接激酶(intergrin-linked kinase,ILK)在人瘢痕成纤维细胞中的表达及对成纤维细胞VEGF的调控作用.方法 8例人增生性瘢痕标本采用组织块法分离培养瘢痕成纤维细胞,选取第5～6代细胞备用.实验分为3组①对照组:不做任何处理,只用含10%FCS的DMEM培养液同步培养;②空质粒组:用空质粒转染人瘢痕成纤维细胞;③ILK cDNA表达质粒转染组:用ILK cDNA表达质粒转染人瘢痕成纤维细胞.首先通过免疫细胞化学染色法检测ILKcDNA转染前后成纤维细胞ILK、VEGF的表达变化;应用实时荧光定量PCR(RT-PCR)及Western blot检测成纤维细胞ILK、VEGF的mRNA和蛋白水平变化;最后采用酶联免疫吸附试验(ELISA法)检测3组成纤维细胞上清液中的VEGF蛋白含量.结果 免疫细胞化学染色结果显示瘢痕成纤维细胞胞浆中ILK表达阳性,VEGF表达不明显,经ILK cDNA转染细胞后ILK与VEGF表达均增强;RT-PCR显示ILK cDNA转染组VEGF mRNA表达(0.338±0.060)均高于对照组(0.022±0.001)和空质粒组(0.028±0.005,P＜0.05);Western blot结果显示ILK cDNA转染组VEGF蛋白表达(0.819±0.019)显著高于对照组(0.607±0.033)和空质粒组(0.591±0.024,P＜0.05);ELISA法检测ILK cDNA转染组的VEGF蛋白含量高于其他两组(P＜0.05).结论 ILK可以上调VEGF mRNA及蛋白水平,并且促进成纤维细胞分泌VEGF,ILK可能通过提高瘢痕成纤维细胞合成分泌VEGF而促进增生性瘢痕血管生成.

Abstract：

Objective To explore the expression of intergrin-linked kinase (ILK) and its effect on VEGF expression in fibroblasts from human hypertrophic scar. Methods Fibroblasts were isolated from hypertrophic scar of 8 patients and cultured in vitro. Then the cells were divided into three groups: ① Cells were cultured only in DMEM containing 10% FCS in the control group; ② Cells were transfected with empty plasmid in the empty plasmid group; ③ Cells were transfected with plasmid experessing ILKcDNA in the ILK cDNA plasmid transfection group. First, the expression of ILK and VECF was observed by immunocytochemistry before and after ILK cDNA transfection. Second, ILK and VEGF mRNA expression was investigated by real-time PCR ( RT-PCR). Third, the protein expression of ILK and VEGF was detected by Western blot. Finally, the protein level of VEGF in supernatant of fibroblasts was measured by ELISA. Results Before ILK cDNA transfection, the expression of ILK was positive and the VEGF expression was weak in cytoplasm of fibroblasts . After ILK cDNA transfection, both the expression of ILK and VEGF was enhanced. The level of VEGF mRNA was significantly higher in ILK cDNA transfection group (0.338 ±0.060) than that in control group (0.022 ±0.001) and empty plasmid group (0.028 ± 0. 005 , P ±0. 05 ). The level of VEGF protein was significantly higher in ILK cDNA transfection group (0. 819 ±0. 019) than that in control group (0. 607 ±0. 033) and empty plasmid group (0. 591 ±0. 024, P ＜0. 05). Secretion of VEGF increased remarkably in ILK cDNA transfection group comparing with the other two groups (P＜0. 05). Conclusions ILK could up-regulate the VEGF mRNA and protein level in human scar fibroblasts. It may play an important role in the angiogenesis in hypertrophic scar.     

小豆蔻明对迟发性脑血管痉挛的作用

目的 探讨小豆蔻明对蛛网膜下腔出血迟发性脑血管痉挛(DCVS)的作用机制.方法 颈内动脉刺破法制作大鼠蛛网膜下腔出血迟发性脑血管痉挛模型,在造模后第1～7天,每天给予小豆蔻明(7.5 mg/kg)腹腔注射,对照组注入等量生理盐水.Image pro-plus软件测量苏木素-伊红(HE)染色大鼠基底动脉管壁厚度,免疫组织化学法检测磷酸化蛋白激酶B (p-Akt),免疫荧光染色检测Akt通路下游增殖蛋白C-myc表达和α-平滑肌肌动蛋白(α-SMA)改变.原位缺口末端标记法(TUNEL)检测细胞凋亡情况.结果 药物治疗组p-Akt、C-myc表达(2.36±0.58、0.96±0.20)、内皮细胞和平滑肌细胞凋亡[(2.77 ±0.29)％]明显低于出血组[5.58±0.65、2.56±0.34、(5.45±0.56)％]和溶媒组大鼠[5.41±0.55、2.67±0.56、(5.53±0.40)％,P＜0.05],而α-SMA表达量(0.23±0.02)高于出血组(0.14±0.02)和溶媒组(0.15 ±0.02,P ＜0.05).结论 小豆蔻明可能通过抑制Akt通路下调C-myc表达,并促进α-SMA表达而影响平滑肌表型转换和增殖,同时能减少内皮细胞和平滑肌细胞凋亡,从而缓解蛛网膜下腔出血所致DCVS.     

基质细胞源性因子-1α/CXC趋化因子受体-4轴经PI3K/Akt通路对胃癌细胞CD133表达的调控作用

目的 观察胃癌中基质细胞源性因子-1α/CXC趋化因子受体-4(SDF-1α/CXCR4)轴经由PI3K/Akt信号通路对下游分子CD133表达及其活性的影响.方法 免疫细胞化学染色检测胃癌KATO -Ⅲ细胞株中CXCR4、Akt、p-Akt及CD133的表达.分别用SDF-1α、AMD3100及LY294002作用于胃癌KATO -Ⅲ细胞株,半定量酶链聚合反应(PCR)检测CXCR4 mRNA和CD133mRNA的表达变化,蛋白免疫印迹法检测CXCR4、Akt、p-Akt及CD133蛋白的表达变化.结果 免疫细胞化学染色证实KATO -Ⅲ细胞呈CXCR4、Akt、p-Akt及CD133阳性表达.SDF-1α组中,CXCR4蛋白(0.980±0.083)、p-Akt蛋白(0.770±0.071)及CD133蛋白(0.890±0.078)表达与对照组(0.750±0.042、0.680±0.038、0.720±0.034)比较明显增高(P＜0.05).与对照组(0.540±0.036、0.520±0.034)比较,CD133 mRNA(0.890±0.061)表达明显增高(P＜0.05).AMD3100组与对照组(0.750±0.042、0.680±0.038、0.720 ±0.034)比较,CXCR4蛋白(0.430±0.055)、p-Akt蛋白(0.350±0.050)及CD133蛋白(0.110±0.060)表达显著下降(P＜0.05).LY294002组中,p-Akt蛋白(0.100 ±0.033)、CD133蛋白(0.440±0.055)表达与对照组(0.680±0.038、0.720±0.034)比较显著下降(P＜0.05).同时,与对照组(0.540±0.036)比较,CD133mRNA(0.310±0.021)表达差异有统计学意义(P＜0.05).结论 刺激或抑制SDF-1α/CXCR4轴可经由PI3K/Akt信号通路上调或下调CD133表达.     

伴侣素CCT-eta在大鼠膝关节纤维化模型中的表达及作用

目的建立大鼠膝关节纤维化模型,探讨伴侣素CCT-eta在关节纤维化中的表达及调节作用。方法手术组取8只雄性SD大鼠,通过固定左膝建立关节纤维化模型。对照组为右侧膝关节,未行干预措施。8周后拆除固定测量膝关节活动度,取膝后关节囊以组织块法分离培养成纤维细胞。用qRT-PCR和Western Blot检测成纤维细胞中CCT-eta和α-SMA的mRNA和蛋白质的表达情况。通过成纤维细胞转染siRNA抑制CCT-eta的表达,再用Transwell技术检测成纤维细胞的迁移能力。手术组和对照组关节活动度比较、手术组和对照组、转染组和手术组的qRT-PCR和Transwell细胞迁移实验数据均采用独立样本t检验,P0.05为有统计学差异。结果手术组固定8周后膝关节伸直角度为(85.7±4.1)°,较对照组(145.7±3.6)°明显降低(t=35.13,P0.05)。手术组较对照组成纤维细胞CCT-eta的mRNA含量和α-SMA的蛋白质的表达明显升高(t=113.40,P0.05)。转染组较对照组α-SMA蛋白质的表达受到显著抑制。手术组成纤维细胞较对照组迁移能力明显增强,但转染组中细胞迁移能力受到抑制(t=270.90,P0.05)。结论 CCT-eta在大鼠膝关节纤维化模型中表达升高,并增强关节囊中成纤维细胞的迁移力,从而促进关节纤维化。     

siRNA敲减整合素连接激酶影响人阴茎海绵体平滑肌细胞功能的体外研究

目的 探讨整合素连接激酶( ILK)基因对人海绵体平滑肌细胞收缩和舒张功能的影响.方法 人海绵体平滑肌细胞为实验对象,分为非沉默组、非处理对照组和ILK小干扰RNA(siRNA)实验组,采用siRNA干扰技术下调细胞中ILK的表达,伸展实验和基质胶黏附实验分别检测ILK基因敲减前后海绵体平滑肌细胞伸展和黏附能力变化,Transwell小室观察ILK表达对海绵体平滑肌细胞迁移能力的影响,荧光标记的鬼笔环肽染色海绵体平滑肌细胞观察ILK基因敲减前后细胞 骨架的变化.结果 黏附实验中,非沉默siRNA组、非处理对照组和实验组siRNA干扰的平滑肌细胞吸光度(A)值分别为0.184±0.034、0.179±0.028和0.092±0.010;迁移实验中,3组穿过Matrigel胶包被的Transwell小室的平滑肌细胞A值分别为0.184±0.017、0.188 ±0.013和0.106±0.003,实验组与非沉默siRNA组比较差异有统计学意义(P＜0.05);非处理对照组平滑肌细胞应力纤维错综分布于细胞周边与胞质内,而实验组的细胞应力纤维仅分布于细胞边缘.结论 ILK下调降低人海绵体平滑肌细胞的黏附、伸展、迁移能力,并通过影响细胞骨架重构参与调节平滑肌收缩与舒张状态,提示ILK基因有可能成为勃起功能障碍基因治疗的有效靶点.     

PI3K/AKT信号通路及AKR1C3在人瘢痕疙瘩形成中的作用机制研究

目的探讨磷脂酰肌醇-3-激酶(PI3K)/蛋白激酶B(AKT)信号通路、活性氧簇(ROS)、醛酮还原酶家族1成员C3(AKR1C3)在瘢痕疙瘩形成中的可能作用及机制。方法从昆明医科大学第一附属医院皮肤科收集9例瘢痕疙瘩组织标本(男6例,女3例,年龄24~40岁),以及6例进行其他手术的志愿者正常皮肤组织标本(男4例,女2例,年龄20~45岁),部分行组织包埋,部分行成纤维细胞原代培养。(1)免疫组织化学检测瘢痕疙瘩和正常皮肤组织中AKT(丝氨酸磷酸化位点473)[p-AKT(S473)]、AKT(苏氨酸磷酸化位点308)[p-AKT(T308)]和AKR1C3的蛋白相对表达量。(2)CCK-8法检测不同浓度(0、5、10、15、20、25、30、35、40、45、50 mmol/L)PI3K特异性抑制剂2-吗啉代-8-苯基色酮(LY294002)对瘢痕疙瘩成纤维细胞增殖的抑制作用,并筛选出LY294002最佳的实验浓度。(3)以ROS检测试剂盒分别检测不同浓度(0、4、6、8、10、12 mmol/L)ROS抑制剂N-乙酰半胱氨酸(NAC)和15 mmol/L LY294002对瘢痕疙瘩成纤维细胞内ROS水平的影响。(4)将瘢痕疙瘩或正常皮肤成纤维细胞分为对照组(正常培养不进行任何处理)、二甲基亚砜(DMSO)组(0.002%DMSO处理)、LY294002组(15 mmol/L LY294002处理)和NAC组(6 mmol/L NAC处理),定量PCR(qPCR)和蛋白质印迹法分别检测成纤维细胞中AKT mRNA、AKR1C3 mRNA及p-AKT(S473)、p-AKT(T308)和AKR1C3蛋白的表达水平。采用SPSS 20.0软件进行统计学分析,数据以±s表示,两组间比较采用独立样本t检验,多组间比较采用单因素方差分析,两两多重比较采用SNK-q检验,P<0.05表示差异有统计学意义。结果(1)免疫组织化学检测结果显示,瘢痕疙瘩组织中p-AKT(S473)、p-AKT(T308)和AKR1C3的蛋白表达水平分别为16.75±3.30、16.20±1.56、26.69±2.50,均显著高于正常皮肤组织的4.02±1.50、1.82±0.50、1.47±1.07(P<0.01)。(2)瘢痕疙瘩成纤维细胞经不同浓度LY294002干预24 h后,15~50 mmol/L LY294002组成纤维细胞增殖抑制率显著高于对照组(0 mmol/L组)(P<0.01)。LY294002最佳实验浓度为15 mmol/L。(3)不同浓度NAC作用于瘢痕疙瘩成纤维细胞1 h后,各组间ROS水平差异有统计学意义(P<0.01),且6 mmol/L NAC组ROS水平(0.72±0.03)最低。15 mmol/L LY294002组ROS水平显著低于对照组(0 mmol/L组)(0.80±0.01 vs.0.86±0.01,P<0.01)。(4)qPCR检测结果表明,瘢痕疙瘩成纤维细胞对照组中AKT、AKR1C3 mRNA表达量分别为1.38±0.09、1.40±0.05,明显高于正常皮肤成纤维细胞的0.97±0.10、0.98±0.03(P<0.01);经15 mmol/L LY294002处理后,瘢痕疙瘩成纤维细胞AKT mRNA表达量明显低于正常皮肤(0.73±0.05 vs.0.89±0.06,P<0.01);经6 mmol/L NAC处理后,瘢痕疙瘩成纤维细胞AKR1C3 mRNA低于正常皮肤(0.43±0.05 vs.0.86±0.03,P<0.01)。蛋白质印迹法检测结果显示,瘢痕疙瘩成纤维细胞中p-AKT(S473)、p-AKT(T308)、AKR1C3蛋白表达量分别为1.19±0.21、0.92±0.04、0.73±0.08,明显高于正常皮肤的0.24±0.06、0.33±0.05、0.31±0.05(P<0.01);经15 mmol/L LY294002和6 mmol/L NAC处理后,瘢痕疙瘩成纤维细胞中p-AKT(S473)蛋白表达量分别为0.92±0.04、0.80±0.20,p-AKT(T308)蛋白表达量分别为0.42±0.04、0.81±0.05,均明显高于正常皮肤(0.23±0.03、0.22±0.05,0.30±0.06、0.32±0.05),但瘢痕疙瘩成纤维细胞AKR1C3蛋白表达量(0.23±0.05)在15 mmol/L LY294002处理后低于正常皮肤(0.30±0.07),在6 mmol/L NAC处理后(0.33±0.07)高于正常皮肤(0.28±0.06)(P>0.05)。结论活化的PI3K/AKT信号通路和AKR1C3促进了瘢痕疙瘩成纤维细胞增殖及瘢痕疙瘩形成。同时,瘢痕疙瘩成纤维细胞内AKR1C3的升高可加速ROS升高。     

油酸对人正常和瘢痕成纤维细胞增殖和分泌炎症介质的影响

目的 探讨油酸对人正常Fb和瘢痕Fb增殖和分泌炎症介质的影响. 方法 体外培养人正常Fb和瘢痕Fb,分别按照随机数字表法分为7组(各组样本数为8):空白对照组,除常规成分外培养液中不再添加其他物质;乙醇对照组,培养液中加入终浓度为体积分数2％无水乙醇;不同浓度油酸组,即0.25、0.50、1.00、2.00以及4.00 mmol/L油酸组,培养液中分别加入相应终浓度的油酸(以含体积分数2％无水乙醇培养液配制).采用锥虫蓝染色法观察各组细胞培养1～5d的生长情况.于倒置相差显微镜和透射电镜下观察2种细胞2个对照组、1.00 mmol/L油酸组细胞培养2d的细胞结构,采用流式细胞仪检测2种细胞2个对照组及1.00 mmol/L油酸组细胞培养2d的细胞周期.噻唑蓝法检测各组细胞培养2d的增殖情况.取各组细胞培养2d时的培养上清液,采用改良Griess法测定NO含量,ELISA法检测TNF-α、IL-6、IL-1β、IL-8含量.对数据进行多因素方差分析及重复测量设计的方差分析. 结果 (1)正常Fb和瘢痕Fb的空白对照组与乙醇对照组比较,各指标均无明显差别.(2)培养2～5d,正常Fb和瘢痕Fb 2.00、4.00 mmol/L油酸组细胞数量均低于对应的2个对照组(F值分别为13.773、11.344,P值均小于0.01).(3)培养2d,正常Fb和瘢痕Fb1.00 mmol/L油酸组细胞数量明显减少,部分细胞开始堆积、变圆易脱落;细胞膜不完整,线粒体空泡变性,核固缩,胞内可见脂滴.(4)正常Fb 1.00 mmol/L油酸组的G0/G1期和G2/M期细胞百分比[(93.56±9.98)％、(2.01士0.75)％]显著高于空白对照组[(84.23±10.96)％、(0.37±0.16)％],F值分别为3.026、34.751,P＜0.05或P＜0.01;S期细胞百分比为(4.42 ±0.87)％,明显低于空白对照组的(16.06±1.74)％,F=136.120,P＜0.01.瘢痕Fb 1.00 mmol/L油酸组G0/G1期和G2/M期细胞百分比分别为(93.86±13.90)％、(1.89±0.66)％,显著高于空白对照组[(83.88±10.42)％、(0.41±0.17)％],F值分别为3.529、32.710,P＜0.05或P＜0.01;S期细胞百分比为(3.87±0.63)％,明显低于空白对照组的(15.89±2.02)％,F=116.508,P＜0.01.(5)正常Fb和瘢痕Fb 0.50 ～4.00 mmol/L油酸组细胞增殖率显著低于对应的2个对照组(F值分别为215.945、194.555,P＜0.05或P＜0.01).(6)正常Fb各浓度油酸组细胞分泌NO水平明显高于2个对照组(F=30.240,P＜0.05或P＜0.01);瘢痕Fb 1.00～ 4.00 mmol/L油酸组细胞分泌NO水平明显高于2个对照组(F=12.495,P＜0.01).正常Fb和瘢痕Fb 2.00、4.00 mmol/L油酸组细胞分泌TNF-α、IL-6水平明显高于对应的2个对照组(F TNF-α值分别为6.911、3.818,FIL-6值分别为16.939、11.600,P ＜0.05或P＜0.01).正常Fb和瘢痕Fb各浓度油酸组细胞分泌IL-1β水平显著高于对应的2个对照组(F值分别为25.117、9.137,P值均小于0.01).正常Fb 1.00～4.00 mmol/L油酸组细胞分泌IL-8水平明显高于2个对照组(F=2.717,P＜0.05或P＜0.01),瘢痕Fb 2.00、4.00 mmol/L油酸组细胞分泌的IL-8水平明显高于2个对照组(F=3.338,P＜0.05).正常Fb和瘢痕Fb相同浓度油酸组各炎症因子水平比较无明显差异(F值为0.120 ～3.766,P值均大于0.05). 结论 高浓度油酸虽能抑制瘢痕Fb增殖,但同时也抑制正常Fb增殖,且高浓度油酸能同时促进正常Fb和瘢痕Fb分泌炎症介质,从而导致过度、持续的炎症反应,不利于创面愈合.     

选择性5-HT2A受体拮抗剂沙格雷酯延缓大鼠移植动脉急性排斥反应后纤维化

目的 研究选择性5-羟色胺2A(5-HT2A)受体拮抗剂沙格雷酯延缓大鼠移植动脉急性排斥反应后纤维化的作用。方法 实验分为3组,同种移植对照组（供、受者分别为Wistar大鼠和SD大鼠）、同系移植对照组（供、受者均为SD大鼠）和实验组（供、受者分别为Wistar大鼠和SD大鼠）,建立大鼠腹主动脉移植急性排斥反应后纤维化模型。术后各组大鼠喂养条件相同,仅实验组大鼠每天给予沙格雷酯灌胃,25 mg/kg。术后第14天和第60天对移植动脉行病理组织学及免疫组织化学检测,观察移植动脉内膜增生情况以及增殖细胞核抗原(PCNA)和平滑肌肌动蛋白(α-SMA)的表达情况。结果 所有移植手术均获成功。术后第14天时,同种移植对照组移植动脉出现典型的急性排斥反应改变。术后第60天,同种移植对照组、同系移植对照组和实验组内膜指数分别为(62.41±6.54)％、(0.94±0.33)％和(16.71±3.94)％,3组间内膜指数的两两比较,差异均有统计学意义(P＜0.05); PCNA和α-SMA细胞阳性率分别为(0.99±0.54)％和(0.79±0.33)％、(22.43±3.40)％和(23.70±2.78)％及(7.37±4.61)％和(8.21±3.11)％,3组间PCNA阳性率的两两比较及α-SMA阳性率的两两比较,差异均有统计学意义(P＜0.05)。结论 大鼠移植动脉急性排斥反应后可继发严重纤维化,沙格雷酯可显著延缓急性排斥反应后纤维化的发生、发展,其作用机制可能与下调PCNA和α-SMA的表达有关。     

Mast cells promote fibroblast populated collagen lattice contraction through gap junction intercellular communication

The release of mast cell granules is commonly associated with inflammation and fibrosis. However, does direct communication between mast cells and fibroblasts through gap junction intercellular communication (GJIC) occur? Fibroblast populated collagen lattice (FPCL) cast with mast cells show enhanced lattice contraction. Do released granules or GJIC between mast cells and fibroblasts promote enhanced lattice contraction? Mast cells preloaded with a fluorescent dye that readily passes through gap junctions were cast in FPCL. Dye passed from mast cells into fibroblasts within these cocultured mast cell‐FPCLs. Fatty acid amide hydrolase inhibitor blocks the breakdown of oleamide, which is a potent endogenous inhibitor of GJIC. GJIC was blocked for 3 days when mast cells were pulsed for 3 hours with fatty acid amide hydrolase inhibitor. Mast cells pretreated with fatty acid amide hydrolase inhibitor cast in cocultured mast cell‐FPCLs failed to enhance cocultured lattice contraction. Mast cell‐FPCLs made with mouse fibroblasts unable to generate GJIC failed to show enhanced lattice contraction. Degranulated mast cells were equal to intact mast cells at enhancing cocultured mast cell‐FPCL contraction. The supernatant from degranulated mast cells had no effect upon FPCL contraction. Therefore, enhanced mast cell‐FPCL contraction appears to be independent of mast cell granules, but dependent upon GJIC between fibroblasts and mast cells. We speculate that mast cell–fibroblast GJIC may play a role in fibrosis.     

High uric acid induces phenotypic transition of renal tubular cells via PI3K/Akt signaling pathway

Objective To investigate the effect and the mechanism of epithelial-mesenchymal transition (EMT) in renal tubular cells induced by uric acid. Methods Normal rat kidney tubular cell line (NRK-52E) were exposed to different concentrations of uric acid (100, 200, 400, 600, 800 μmol/L UA) for 48 hours to induce EMT. Morphological changes of the NRK-52E cells were examined under an inverted phase contrast microscope. The protein expression of E-cadherin, α-SMA, p-Akt and Akt were detected by Western blotting. The distribution of E-cadherin and α-SMA were detected by immunofluorescence. NRK-52E cells were pretreated by different concentrations of LY294002(0, 2.5, 5, 10, 15 μmol/L), the inhibitor of PI3K/p-Akt signaling pathway, and then processed by uric acid (400 μmol/L) for 48 hours. Western blotting was used to detect the protein expression of p-Akt and Akt. NRK-52E cells were then divided into four groups: normal group (N), uric acid group (UA), LY294002 group (LY), uric acid with LY294002 group (UA+LY). The protein expression of E-cadherin and α-SMA were detected by Western blotting, the distribution of E-cadherin, α-SMA and p-Akt were detected by immunofluorescence. Results There was abundant cellular expression of E-cadherin in unstimulated renal tubular cells whereas its expression was significantly decreased in uric acid-stimulated cells (P＜0.05). In addition, uric acid induced de novo expression of α-SMA in contrast to almost negative staining in untreated cells (P＜0.05). p-Akt were obviously increased in high uric acid group (P＜0.05) and Akt changed not significantly (P＞0.05). NRK-52E cells transformed into elongated fibroblast-like cells from cuboidal clustered epithelial cells. These indicated that uric acid has induced EMT and activated PI3K/p-Akt signaling pathway in NRK-52E cells. However, the above effects of uric acid were abolished when p-Akt was blocked by the PI3K inhibitor (10, 15 μmol/L LY294002), indicated that LY294002 has reversed the trend of EMT. Conclusions High uric acid induces phenotypic transition of renal tubular cells probably via activating PI3K/Akt signaling pathway.     

Effects of benazepril on the expressions of intergrin-linked kinase and α-smooth muscle actin in glomerular mesangial cells exposed to high glucose

Objective To investigate the effect of benazepril on intergrin-linked kinase (ILK) and α-smooth muscle actin (α-SMA) expression in glomerular mesangial cells induced by high-glucose. Methods The mesangial cells from SD rat (HBZY-1) were cultured conventionally and randomly divided into four groups: normal glucose (D-glucose 5.5 mmol/L, group NG), mannitol-treated group (mannitol 20 mmol/L, group MG), high glucose (D-glucose 30 mmol/L, group HG), Benazepril-treated high glucose group (D-glucose 30 mmol/L＋Benazepril 10 μmol/L, group ACEI). Cells from NG, MG, HG, ACEI gronps were harvested after 3, 6, 12, 24, 48 and 72 hours of treatment respectively. The mRNA expressions of ILK and α-SMA were detected by RT-PCR. The protein levels of ILK and α-SMA were detected by Western blotting and immunofluorescence. Results The expressions of ILK mRNA and protein in HG group were significantly increased compared with those in NG group (all P＜0.05). The increased expressions of ILK and α-SMA in HG group were time-dependent and the expression reached the peak at 48 h (ILK, P＜0.05) or 72 h (α-SMA, P＜0.01). The expressions of ILK and α-SMA in ACEI group were lower than those in HG group (all P＜0.01), but failed to rescue to the same level as those in NG. There was no significant differences of ILK expressions between MG group and NG group at the same time point (P＞0.05). The expressions of α-SMA mRNA and protein in MG were higher than that in NG (P＜0.05), which suggest that high osmotic pressure could cause the increasing of α-SMA. Conclusions Benazepril can decrease the expressions of ILK and α-SMA to inhibit the process of fibrosis in DN and mediate the phenotypic transformation of glomerular mesangial cells. The phenotypic transformation of glomerular mesangial cells in glucose may also depend on high osmotic pressure in DN.     

褪黑激素对人增生性瘢痕成纤维细胞增殖和凋亡的影响

目的 探讨褪黑激素对人增生性瘢痕Fb增殖和凋亡的影响与机制. 方法 采用组织块法分离培养人增生性瘢痕Fb.按随机数字表法将细胞分为低、中、高浓度组和对照组.前3组细胞分别采用含1 × 10-5、1×10-3、1 mmol/L褪黑激素的培养液培养,对照组不加褪黑激素常规培养.处理后24 h进行如下检测:对各组细胞进行形态学观察;用四氮唑复合物( XTT)-硫酸酚嗪甲酯(PMS)比色法检测细胞增殖活性;对细胞行膜联蛋白V-异硫氰酸荧光素(FITC)和碘化丙啶(PI)双染色后,用流式细胞仪分析细胞周期和凋亡情况;荧光定量RT-PCR法检测细胞周期蛋白E(cyclin E)、p53和Fas mRNA表达量.对数据行方差分析和LSD检验. 结果 形态学观察显示,对照组Fb为长梭形,呈集落分布;3个浓度组Fb随着褪黑激素浓度升高,细胞逐渐分散,胞体变形缩小,胞膜皱缩,核质比例减小.对照组、低浓度组、中浓度组、高浓度组Fb增殖活性(吸光度值)依次下降,分别为1.79±0.10、1.49±0.15、1.24±0.20、0.92±0.09(F=67.61,P ＜0.05);S期细胞百分比依次下降,分别为(16.9±1.3)％、(10.6±1.1)％、(6.1±1.2)％、(3.2±0.8)％(F=286.10,P ＜0.05);G2/M期细胞百分比依次下降,分别为(16.7±1.6)％、(13.5±1.1)％、(9.8±1.0)％(6.0±0.7)％(F=162.69,P＜0.05);早、晚期凋亡细胞百分比依次升高(F值分别为424.05、236.44,P值均小于0.05).对照组、低浓度组、中浓度组、高浓度组细胞cyclin E的mRNA表达量依次下降,分别为2.90±0.30、1.58±0.21、0.90±0.20、0.24±0.12(F=266.79,P＜0.05);p53和Fas mRNA表达量依次升高(F值分别为10.11、12.03,P值均小于0.05). 结论 褪黑激素可通过影响细胞cyclin E、p53和Fas基因的表达,抑制增生性瘢痕Fb增殖并诱导该细胞凋亡.     

A review of fibroblast-populated collagen lattices

Bell's introduction of the fibroblast-populated collagen lattice (FPCL) has facilitated the study of collagen–cell interactions. As a result of the numerous modifications of the casting of FPCLs, the in vivo applications of these in vitro findings have been confusing. Here experimental FPCL contraction findings are viewed in regard to three proposed mechanisms responsible for lattice contraction. The cellular mechanisms responsible for generating FPCL contraction are cell contraction, cell tractional forces related to cell locomotion, and initial cell elongation and spreading.     

HGF拮抗TGF-β1诱导腱鞘成纤维细胞α-SMA及细胞外基质合成

目的 研究HGF能否阻抑TGF-β1诱导的腱鞘成纤维细胞α-SMA及细胞外基质过度合成.方法 选取成年新西兰大白兔7只,体重3.75～4.00 kg,无菌切取前肢中趾趾深屈肌腱,进行腱鞘成纤维细胞的分离和培养,待细胞生长成单层后,以胰蛋白酶消化传代.取第3代成纤维细胞用于实验,当细胞达到70%融合时,培养液中加入TGF-β1(5 ng/ml)及HGF(10～40 ng/ml).培养72 h后,利用Westernblot检测α-SMA表达;ELISA测定细胞Ⅰ型胶原及纤维结合素的表达.结果 TGF-β1能显著诱导α-SMA表达,半定量分析提示,TGF-β1作用后的成纤维细胞α-SMA表达量是对照组的1.8倍.随HGF的同时加入,α-SMA的表达则明显受抑制(P＜0.05),且随HGF浓度的升高其阻抑作用呈逐渐增强趋势.TGF-β1同样能诱导Ⅰ型胶原及纤维结合素的表达(P＜0.01),而HGF则可以有效地阻抑其表达,其效应呈剂量依赖性(P＜0.05).结论 HGF可以有效阻抑TGF-β1诱导的腱鞘成纤维细胞α-SMA、Ⅰ型胶原及纤维结合素的表达,这为利用HGF预防和治疗屈指肌腱损伤后粘连及瘢痕在细胞和分子水平提供了依据.