苯妥英钠促进心肌梗死后大鼠心室基质金属蛋白酶活性及胶原沉积

目的 研究苯妥英钠对急性心肌梗死(AMI)后大鼠心室基质金属蛋白酶(MMPs)活性和胶原合成的影响及其促进心肌梗死后组织修复的机制.方法 用Wistar大鼠建立AMI模型,将大鼠分成苯妥英钠组、对照组和假手术组,在造模后处死动物,取心室,一部分用组织学方法分析;另一部分采用Gelatin Zymography测定MMPs活性.结果 苯妥英钠组14 d时梗死区厚度大于对照组,非梗死区心肌横断面积小于对照组;AMI后梗死区胶原容积分数苯妥英钠组高于对照组;AMI后苯妥英钠组Ⅰ/Ⅲ型胶原高于对照组(P＜0.05);心室梗死区MMPs活性相对于假手术组明显上调(P＜0.05).结论 苯妥英钠可促进AMI后早期梗死区胶原的合成,MMP-2和MMP-9可能参与了此机制.     

洛沙坦对急性心肌梗塞后大鼠心肌间质金属蛋白酶活性的影响

目的:探讨急性心肌梗塞后,梗塞区心肌间质金属蛋白酶(MMPs)活性的动态变化及洛沙坦对其的影响。方法:结扎SD大鼠冠状动脉前降支复制急性心梗模型,随机分成对照组和用药组。采用MPA-V型多导生物信号分析系统监测血流动力学指标;采用酶谱法测定54kD间质金属蛋白酶1(MMP-1)、58kD和62kD间质金属蛋白酶2(MMP-2)的活性;采用氯氨T法测定胶原蛋白的含量。结果:梗塞区MMPs活性表现出-过性升高,第3d比假手术组高4.5倍,第7d高6.5倍达高峰,然后下降,第14d降至2倍,第42d仍高1.5倍。用药组MMP-1比同时间点对照组降低33%,MMP-2低至50%;左室重量与体重之比(LVW/BW),第14d和第42d明显低于对照组(P<0.01);梗塞区胶原密度第42d显著低于假手术组(P<0.01)。用药组心脏舒张末期压力于第3d一过性高于对照组,第7、14、42d均低于对照组。收缩压最大上升速度高于对照组(P<0.05)。结论:心肌梗塞后梗塞区MMPs被激活,加速胶原分解代谢;洛沙坦降低MMPs活性,降低胶原分解代谢,同时抑制胶原合成代谢,使心梗后期胶原含量降低,具有改善心脏功能,保护心肌的作用更多     

家兔慢性冬眠心肌MMP-2、MMP-9和TIMP-2表达与胶原重构

目的观察家兔慢性冬眠心肌(CHM)心肌间质胶原纤维变化及基质金属蛋白酶-2,9(MMP-2、MMP-9)及其抑制剂(TIMP-2)的表达。方法27只家兔随机分为模型组(CHM,n=15)及假手术组(SHAM,n=12)。观察心肌间质胶原容积百分比(ICVF)、Ⅰ型和Ⅲ型胶原纤维比例、计算Ⅰ/Ⅲ型胶原纤维比例记分(CRS);免疫组化染色及Western blot观察MMP-2、MMP-9及TIMP-2表达。结果与SHAM组相比,CHM组ICVF显著增加(P<0.01);Ⅰ/Ⅲ胶原比例增高;CRS显著增加(P<0.01);MMP-2及MMP-9的表达明显增多(P<0.01),TIMP-2的表达明显减少(P<0.01)。结论在CHM过程中,MMPs/TIMPs比例失平衡,可能是CHM间质胶原重构的机制之一。     

参麦注射液对糖尿病心肌病大鼠心肌纤维化的干预作用及相关机制探讨

 目的：探讨参麦注射液对糖尿病心肌病心肌纤维化的干预作用并初步探讨其机制。方法：将30只Wistar大鼠分为对照组、糖尿病组以及治疗组,每组各10只。采用链脲佐菌素单次腹腔注射的方法制作大鼠糖尿病模型,以枸橼酸缓冲液腹腔注射为对照,治疗组则采用腹腔注射的方式给予参麦注射液干预治疗。采用心室插管对大鼠心功能进行评估;Masson染色观察大鼠心脏组织中胶原水平;二氢乙啶染色观察大鼠心脏组织中活性氧（ROS）水平;Western blotting观察大鼠心肌组织中I 型胶原、基质金属蛋白酶2（MMP-2）以及金属蛋白酶组织抑制剂2（TIMP-2）的表达水平。结果：与对照组相比,糖尿病组心功能显著下降（P＜0.05）;而治疗组心功能则显著恢复（P＜0.05）。与对照组相比,糖尿病组心肌组织ROS及胶原生成水平显著升高（P＜0.05）,但经参麦注射液治疗后均显著降低（P＜0.05）。与对照组相比,糖尿病组I 型胶原及TIMP-2表达水平显著升高（P＜0.05）,而MMP-2水平显著降低（P＜0.05）;与糖尿病组相比,治疗组I 型胶原及TIMP-2水平显著降低（P＜0.05）,而MMP-2水平则显著升高（P＜0.05）。结论:参麦注射液可能通过抑制氧化应激损伤而减轻糖尿病心肌病心肌纤维化程度。     

缬沙坦对阿霉素心肌病大鼠的心脏保护作用及机制研究

目的： 探讨AT1受体阻滞剂缬沙坦对阿霉素心肌病(ADR-DCM)大鼠的心脏保护作用及其机制。方法: 雄性Wistar大鼠分3组：(1)阿霉素心肌病组(ADR-DCM，n=25)，阿霉素 2.5 mg/kg，尾静脉注射，每周1次，连续10周；(2)阿霉素心肌病+缬沙坦治疗组(ARB，n=10)， 缬沙坦 30 mg/kg，每天1次，灌胃治疗；(3)正常对照组(CON，n=10)。12周时进行超声和血流动力学检测，氯胺T法检测羟脯氨酸及胶原含量， Western印迹分析检测MMP-2、MMP-9及TIMP-1的表达，明胶酶谱法检测MMPs活性。结果: ARB组死亡率明显低于ADR-DCM组(20% vs 40%，P<0.01)。ADR-DCM组大鼠左室内径大于CON组，心功能明显低于CON组， ARB组左室内径增加程度及心功能各项指标变化低于ADR-DCM组。ADR-DCM组心肌羟脯氨酸及胶原含量高于CON组， ARB组显著低于ADR-DCM组(P<0.01)。ADR-DCM组左室心肌MMP-2、MMP-9蛋白表达及MMPs明胶酶活性明显高于CON组 (P<0.01)，ARB组MMP-2、MMP-9表达及活性明显低于ADR-DCM组(P<0.01)，而TIMP-1的表达在3组间均无显著差异(P>0.05)。结论: 缬沙坦部分通过抑制MMPs表达及活性逆转ADR-DCM左室重构，改善心功能。     

心室重构及心衰时基质金属蛋白酶的活性变化

心室重构引起心肌纤维化和进行性心室扩张 ,最终导致心力衰竭。在心肌中存在能降解有所心脏基质成分的基质金属蛋白酶 (MMPs) ,是重构过程中引起心脏基质降解和心肌纤维化的主要因素。在心室重构和心力衰时MMPs的活性升高 ,使纤维胶原降解、细胞外基质重构和进行性心室扩张。研究MMPs的活性变化对限制心室重构和延缓心衰进展的治疗方面具有指导意义     

基质金属蛋白酶及其组织型抑制剂活性及表达失衡与高血压性左心室重塑的关系

目的： 探讨慢性压力负荷增高时，大鼠左心室（LV）基质金属蛋白酶（MMPs）/组织型基质金属蛋白酶抑制剂（TIMPs）失衡与LV重塑的关系。方法：40只6周龄雄性卒中易感性自发性高血压大鼠（SHR-SPs）作为研究对象，10只同周龄雄性Wistar-Kyoto（WKY）大鼠作为对照。6个月后，以Millar压力容积导管评价2组大鼠的在体LV血流动力学，并对2组大鼠的心脏进行组织病理学、明胶酶谱和免疫印迹法分析。结果：反映LV收缩与舒张功能的血流动力学参数在2组间有显著差异（P＜0.05）；SHR-SPs心脏胶原容积分数、血管周胶原面积/管腔面积、心肌横断面积、心室壁动脉中膜面积/管腔面积均增高（P＜0.05）；心肌MMP-2活性、蛋白含量及TIMP-1蛋白含量在SHR-SPs中明显增高（P＜0.05）。结论：慢性压力超负荷能够导致心脏细胞外基质代谢失调及MMPs/TIMPs系统失衡，继而产生心室腔扩张、LV收缩与舒张功能障碍。     

Ⅱ型糖尿病大鼠窦房结间质胶原重构

目的:探讨Ⅱ型糖尿病大鼠窦房结内Ⅰ、Ⅲ型间质胶原重构及胰岛素对其的影响.方法:高糖高脂饮食加小剂量链脲佐菌素腹腔注射(STZ, 30mg/kg)制备Ⅱ型糖尿病大鼠模型,并随机分为正常对照组、糖尿病组和胰岛素治疗组(每只3U/d股内侧皮下注射),对照组和糖尿病组注射等剂量的生理盐水每天1次,持续喂养4个月;窦房结组织行SABC法免疫组织化学显色,检测窦房结组织中的I型和Ⅲ型胶原的表达及变化.结果:糖尿病组I、 Ⅲ型胶原纤维在窦房结内明显增加,而治疗组较糖尿病组呈显著下降.图像分析结果显示Ⅰ、 Ⅲ型胶原表达量为糖尿病组>治疗组>对照组.糖尿病组Ⅰ/Ⅲ型胶原比例明显较对照组上升.结论:Ⅱ型糖尿病大鼠窦房结16周后出现间质胶原重构,胶原类型比例失衡;Ⅱ型糖尿病大鼠行胰岛素降低血糖后可不同程度下调窦房结间质胶原的沉积,一定程度上逆转胶原类型比例紊乱.     

同种异体移植骨髓间质干细胞治疗大鼠心梗后心室重构

目的： 观察骨髓间质干细胞（MSCs）移植对大鼠心梗后心室重构和心功能的影响，比较成年大鼠MSCs与乳鼠MSCs移植疗效，初步探讨同种异体移植的可行性。方法: 分别取大鼠和乳鼠的骨髓，体外分离、扩增培养MSCs，Brdu标记。在结扎冠脉后1-2 h 分别将大鼠MSCs和乳鼠MSCs分点注射到异体大鼠心脏梗死边缘区，6周后，采用超声心动图和解剖直测法获得大鼠心功能、心室重构和病理学资料。结果: 细胞移植组左室舒张末期内径和收缩末期内径短于、室壁厚于对照组，重量指数和心室腔都明显小于对照组。组织病理表现细胞移植组心梗区心肌数目多于、血管密度大于对照组，细胞外基质胶原的形成和血管周围胶原沉积均明显少于对照组，心梗区可见Brdu阳性细胞。但大鼠MSCs移植组和乳鼠MSCs移植组间无明显差异。结论: 同种异体骨髓间质干细胞可以在心梗区定植，减少胶原形成，促进心肌和血管生成，从而延缓心梗后心室重构，提高左室收缩和舒张功能。成年鼠干细胞移植与乳鼠干细胞移植具有相似的效果。     

无创性肢体缺血预适应对大鼠缺血再灌注损伤心肌基质金属蛋白酶的影响

目的观察大鼠无创性肢体缺血预适应(LIP)对心肌缺血再灌注损伤后心肌形态学、梗死面积和心肌MMP-2、MMP-9和TIMP-1的影响。方法通过连续3 d每天1次3个循环的下肢无创性5 min缺血、5 min再灌建立LIP模型。大鼠随机分成3组,心肌缺血再灌注组(I/R)、心肌缺血预适应组(CIP)和LIP组。以HE染色法观察心肌形态学改变;红四氮唑染色法确定心肌梗死范围,IS=IA/AAR×100%;免疫组化法测定心肌MMP-2、MMP-9和TIMP-1水平。结果缺血30 min再灌注120 min后,I/R组IS为(44.5±8.1)%;与I/R组比较,CIP和LIP均能明显改善心肌损伤的形态学改变,降低心肌细胞的肿胀、减少间质出血和炎性细胞的浸润。CIP使IS降低35.7%,缺血区心肌MMP-2降低42.1%,MMP-9降低43.3%,TIMP-1水平增加40.0%;LIP使IS降低42.9%,缺血区心肌MMP-2降低41.2%,MMP-9降低46.6%,TIMP-1水平增加53.8%。结论LIP不仅能改善缺血再灌注损伤大鼠心肌形态学改变、减少心肌梗死面积,而且能降低心肌细胞基质的损伤,起到保护心肌的作用。     

基质金属蛋白酶9在大鼠糖尿病肾病发病中的作用

目的 探讨糖尿病肾病大鼠肾局部金属蛋白酶9(MMP-9)在糖尿病肾病发生发展的作用.方法 健康雌性清洁级大鼠,随机分成糖尿病组和正常对照组,采用腹腔注射链脲佐菌素制备糖尿病大鼠模型.分别于4、8周处死,应用免疫组化及酶谱分析方法(zymography)观察各组肾组织MMP9的蛋白表达及其活性水平,分析MMP-9与细胞外基质Ⅳ型胶原、层粘连蛋白(LN)的相关性.结果 MMP-9在正常对照组肾小球、肾小管细胞均有阳性表达(4周,26.63%+2.94%;8周,29.86%±0.89%);而糖尿病组随病程延长表达明显减弱(4W,16.11%±2.86%;8周,13.14%±2.68%),MMP-9活性也明显降低(正常组4周110.47±7.12;8周,111.50±6.95;糖尿病组4周82.74±10.92;8周,80.05±12.83),两组间各项指标的差异有统计学意义(均P＜0.01).MMP-9活性与Ⅳ型胶原(r=-0.852,-0.795,P＜0.01)、LN(r=-0.897,-0.832,P＜0.01)呈显著负相关.结论 糖尿病肾病时肾组织中MMP-9表达水平降低,糖尿病肾病的发病机制可能与MMP-9水平降低有关.     

Selective progesterone receptor modulator asoprisnil down-regulates collagen synthesis in cultured human uterine leiomyoma cells through up-regulating extracellular matrix metalloproteinase inducer

BACKGROUND: A recent clinical trial demonstrated that selective progesterone receptor modulator asoprisnil is effective in reducing uterine leiomyoma volume. We investigated the effects of asoprisnil in vitro on the expression of the extracellular matrix (ECM)-remodeling enzymes and collagens in cultured leiomyoma and matching normal myometrial cells. METHODS: The expression of extracellular matrix metalloproteinase inducer (EMMPRIN), matrix metalloproteinases (MMPs), tissue inhibitors of MMP (TIMPs) and collagens were assessed by western blot analysis. RESULTS: Untreated cultured leiomyoma cells had significantly lower EMMPRIN (P < 0.05), MMP-1 (P < 0.05) and membrane type 1-MMP (MT1-MMP) (P < 0.01) protein contents, but significantly higher TIMP-1 (P < 0.05), TIMP-2 (P < 0.01), type I (P < 0.05) and type III (P < 0.01) collagen protein contents compared with untreated cultured myometrial cells. Treatment with asoprisnil at concentrations > or =10(-7) M for 48 h significantly (P < 0.05) increased EMMPRIN, MMP-1 and MT1-MMP protein contents, and decreased TIMP-1 (P < 0.05), TIMP-2 (P < 0.01), type I (P < 0.01) and type III (P < 0.05 at 10(-7) M; P < 0.01 at 10(-6) M) collagen protein contents in cultured leiomyoma cells compared with control cultures. However, asoprisnil treatment did not affect the protein contents of ECM-remodeling enzymes and collagens in cultured myometrial cells. CONCLUSIONS: These results suggest that asoprisnil may reduce collagen deposit in the ECM of cultured leiomyoma cells through decreasing collagen synthesis and enhancing the expression of EMMPRIN, MMPs and TIMPs without comparable effects on cultured myometrial cells.     

基质金属蛋白酶及其组织抑制因子在左心室机械辅助减负荷模型中的表达

目的 研究基质金属蛋白酶(MMP)及其组织抑制因子(TIMP)在左心室机械辅助减负荷模型中的表达,探讨左心室减负荷后心肌逆向重构的分子机制.方法 结扎Lewis大鼠冠状动脉左前降支诱导心力衰竭,4周后将14只心力衰竭大鼠随机分为心力衰竭组(n=7)与移植组(n=7).将供体移植组心力衰竭大鼠的心脏及右肺移植到受体正常Lewis大鼠的腹部,通过供体的升主动脉与受体的降主动脉吻合.7只正常Lewis大鼠作为正常组.结扎左前降支4周后心脏超声测量3组大鼠心室直径和心肌梗死范围.移植2周后,称取各组大鼠心脏、左心室质量;显微镜观测左心室心肌细胞直径与心肌纤维化程度;采用实时荧光定量PCR检测MMP-1、MMP-9、TIMP-1的mRNA表达及计算MMP-1mRNA/TIMP-1 mRNA的比值.结果 结扎左前降支4周后,心力衰竭组及移植组舒张末直径(LVEDD)较正常组升高、左心室短轴缩短率(LVFS)较正常组下降,而此两组间LVEDD、LVFS及心肌梗死范围比较差异无统计学意义,两组的心力衰竭严重程度差异也无统计学意义.心力衰竭组心脏、左心室质量和左心室心肌细胞直径大于移植组与正常组;移植组心脏、左心室质量、左心室心肌细胞直径接近正常组.心肌纤维化的程度移植组＞心力衰竭组＞正常组[(7.90±2.32)％比(4.20±1.84)％比(1.54±0.31)％,均P＜0.05].心力衰竭组和移植组MMP-1、MMP-9mRNA表达均高于正常组(1.89±0.23、1.32±0.16比0.41±0.01,2.03±0.15、1.50±0.13比0.46+0.01,均P＜0.05),但心力衰竭组与移植组比较差异无统计学意义.心力衰竭组TIMP-1mRNA表达低于正常组与移植组(0.72±0.18比1.21±0.02、1.68±0.21,均P＜0.05);正常组与移植组比较差异无统计学意义.心力衰竭组MMP-1 mRNA/TIMP-1mRNA比值较正常组及移植组明显增高(2.03±0.15比0.30±0.01、0.81±0.11,均P＜0.05);正常组与移植组差异则无统计学意义.结论 左心室减负荷后,心肌逆向重塑的过程伴随着心肌细胞MMP及TIMP水平的改变.     

内源性碱性成纤维细胞生长因子是大鼠对抗心脏缺血/再灌注损伤的保护因子

目的:观察内、外源性碱性成纤维细胞生长因子(bFGF)在大鼠心脏缺血/再灌注(I/R)损伤中的作用。方法:在大鼠离体心脏I/R模型上分别给以bFGF和bFGF抗血清,以生理多导仪测定心率、±LVdp/dt_max及左心室终末舒张压(LVEDP)变化,并测定冠脉流量、冠脉流出液中蛋白、肌红蛋白含量、乳酸盐脱氢酶(LDH)活性以及心肌组织钙、丙二醛(MDA)、三磷酸腺苷(ATP)含量和蛋白激酶(PKC)、丝裂素活化蛋白激酶(MAPK)活性。结果:I/R组心功能显著低于对照组,冠脉流出液中蛋白、肌红蛋白含量、LDH活性及心肌MDA、钙含量显著升高,ATP含量显著降低(均P＜0.01)。bFGF组±LVdp/dt_max较I/R组分别高42.8％和25.6％,LVEDP低40.0％,再灌末心率/预灌末心率(HRr/HRi)及冠脉流量的(B/A)分别高42.3％和20.3％,冠脉流出液中蛋白、肌红蛋白含量及LDH活性分别少28.8％、30.2％(均P＜0.01)和32.3％(P＜0.05),心肌MDA和钙含量分别少44.4％和35.6％,ATP含量高33.8％。心肌PKC、MAPK活性分别高41.3％和10.1％(均P＜0.01);bFGF抗血清组±LVdp/dt_max较I/R组分别低35.1％和38.1％,LVEDP高92.5％,HRr/HRi及冠脉流量的B/A分别少36.0％和45.4%,冠脉流出液中蛋白、肌红蛋白和LDH漏出分别多54.3%、96.2%和34.4%,心肌MDA和钙含量分别高23.6%和49.7%,ATP含量低27.8%,心肌PKC及MAPK活性分别低20.9%和7.7%(均P<0.01)。结论:内源性bFGF是大鼠对抗心脏缺血/再灌注损伤的保护因子。     

Early Activation of Metalloproteinases after Experimental Myocardial Infarction Occurs in Infarct and Non-infarct Zones

The collagen matrix of the heart forms a network linking muscle fibers, muscle bundles, and intramyocardial blood vessels. Collagen turnover in the heart is normally a dynamic process that involves both collagen synthesis and degradation. Collagen breakdown generally involves its chemical digestion by matrix metalloproteinases (MMPs) which are activated in tissue repair, wound healing, and myocardial ischemia. We studied activation of MMPs by zymography in infarct (anterolateral wall) and non-infarct (septum) zones of rat hearts following coranary artery ligation, as well as in sham operated rats. Rats were sacrificed at 30 minutes, 1 hour, 2 hours, 4 hours, and 24 hours post infarction (six hearts for each time period). MMP activity was detected at different molecular weights, with bands at 54 kDa (MMP-1), 62 kDa (MMP-2), and 92 kDa (MMP-9) being the most prominent. MMP activities were indexed by densitometer optical reading. Activity was detected as early as 1 hour post infarct in the MI and remote zones at the 54 kDa (MMP-1) ( p < 0.01) and 62 kDa bands (MMP-2) ( p < 0.001), and at 2 hours post infarct in the infarct zone only at 92 kDa (MMP-9) ( p < 0.05). MMPs are activated early after infarction both in the infarct and importantly, non-infarct zones. This may contribute to collagen breakdown, infarct expansion, and left ventricular remodeling, known to occur early after infarction in experimental and clinical settings.     

Right ventricular expression of extracellular matrix proteins, matrix-metalloproteinases, and their inhibitors over a period of 3 years after heart transplantation

Fibrillar collagens I and III, nonfibrillar collagen IV, and the glycoproteins fibronectin and laminin, are elements of the myocardial extracellular matrix (ECM). Alterations in the normal concentrations and ratios of these elements may reflect remodeling in response to physiologic stress. In the case of patients' post-heart transplantation (HTx), specific patterns of alteration may herald myocardial dysfunction. Right ventricular biopsies were taken from the same 28 HTx patients before implantation and 1 week, 2 weeks, and 1, 2, and 3 years after HTx. The above-noted five ECM proteins, six matrix metalloproteinases (MMPs) and two of their tissue inhibitors (TIMPs) were detected by immunohistochemistry and scored as cells per square millimeter or semiquantitatively. The total connective tissue fibers were detected by connective tissue stain and morphometry. Variations in these ECM components were followed in the same patient cohort over 3 years. In summary, during the first 2 weeks after HTx, a predominant increase in connective tissue occurred. Increases in MMP-8 and MMP-9 were found. By 3 years after transplantation, there was a decrease of connective tissue fibers and a significant reduction of all ECM components and an increase in MMPs and TIMPs. These findings may reflect a pattern of remodeling specific to the transplanted heart.     

A pilot study of matrix metalloproteinases on the model of daunorubicin-induced cardiomyopathy in rabbits

Matrix metalloproteinases (MMPs), activated by oxidative stress, play a key role during cardiac remodeling. In the present study we aimed to assess the role of MMPs in experimental cardiomyopathy induced by repeated 10-week administration of daunorubicin (3 mg/kg i.v.) to rabbits. In the daunorubicin group, the plasma cardiac troponin T levels (cTnT - a marker of myocardial necrosis) were significantly increased (p<0.05), commencing with the 8th administration compared with the controls. The amount of collagen (an estimate of fibrosis) was also significantly higher in the daunorubicin group (13.39 +/- 0.97 mg/g wet weight) compared to the control group (10.03 +/- 0.65 mg/g wet weight). In both groups, the LV MMP-activity was observed only in the gelatine substrate in the 70 kDa region (MMP-2), while no MMPs activities were detectable either in the casein or collagen containing zymograms. At the end of the experiment, the MMP-2 activity was slightly up-regulated (by 16 %) compared with the controls.     

Progesterone receptor modulator CDB-2914 induces extracellular matrix metalloproteinase inducer in cultured human uterine leiomyoma cells

Effects of progesterone receptor modulator CDB-2914 on the expression of the extracellular matrix (ECM) components were examined in cultured human uterine leiomyoma and myometrial cells. ECM metalloproteinase inducer (EMMPRIN), matrix metalloproteinases (MMPs), tissue inhibitors of MMP (TIMPs) and collagen levels were assessed by Western blot analysis, MMP activity assay and real-time RT-PCR. RNA interference (RNAi) of EMMPRIN was performed using small interfering mRNA. In cultured leiomyoma cells, CDB-2914 treatment at concentrations greater than or equal to 10(-8) M significantly increased EMMPRIN, MMP-1 and MMP-8 protein contents and MMP-1, MMP-2, MMP-3 and MMP-9 mRNA levels, and activity of MMP-1, MMP-2, MMP-3 and MMP-9 in the medium. TIMP-1 and TIMP-2 were significantly decreased at mRNA and protein levels by CDB-2914 treatment at concentrations > or =10(-7) M in these cells. CDB-2914 treatment decreased types I and III collagen protein contents. However, CDB-2914 treatment did not affect the ECM component expression in cultured myometrial cells. RNAi of EMMPRIN abrogated CDB-2914-mediated both induction of MMPs and reduction of TIMPs and collagens in cultured leiomyoma cells. These results suggest that CDB-2914 modulates the expression of EMMPRIN, MMPs, TIMPs and collagens in cultured leiomyoma cells without comparable effects on myometrial cells.     

Regulation of matrix metalloproteinases and their inhibitors in the left ventricular myocardium of patients with aortic stenosis

Aortic stenosis (AS) results in myocyte and extracellular matrix remodeling in the human left ventricle (LV). The myocardial renin-angiotensin system is activated and collagens I and III and fibronectin accumulate. We determined the yet unknown regulation of enzymes that control collagen turnover, i.e., LV matrix metalloproteinases (MMP) and their tissue inhibitors (TIMPs) in human AS. We compared LV samples from AS patients undergoing elective aortic valve replacement (n=19) with nonused donor hearts with normal LV function (controls, n=12). MMP-2, MMP-9, MT1-MMP, and extracellular matrix metalloproteinase inducer (EMMPRIN), TIMP-1, TIMP-2, TIMP-3, and TIMP-4 mRNA were quantitated by real-time RCR. MMP-1, MMP-2, MMP-3, TIMP-3, TIMP-4, and EMMPRIN protein were measured by immunoblotting and MMP-9 and TIMP-1 protein by ELISA. Gelatinolytic MMP-2 and MMP-9 activity was measured by zymography. MMP-2 was increased in AS at mRNA, protein, and activity levels (131%, 193%, and 138% of controls). MMP-3 protein (308%) and EMMPRIN mRNA and protein were also upregulated (171% and 200%). In contrast, MMP-1 (37%) and MMP-9 mRNA, protein, and activity (26%, 21%, and 52%) were downregulated. MMP-9 activity was inversely correlated with LV size. TIMP-1 mRNA and protein were decreased (55% and 73%). In contrast, TIMP-2 mRNA (358%), TIMP-3 mRNA and protein (145% and 249%) were increased. TIMP-4 mRNA was not altered, but TIMP-4 protein was upregulated to 350%. Changes were similar in AS patients with normal and impaired LV ejection fraction. The dysregulation of myocardial MMPs and TIMPs in human AS starts at an early disease stage when LV function is still normal. In spite of upregulation of some MMPs the balance between MMP and TIMP is shifted towards MMP inhibition in human AS and may contribute to collagen accumulation.     

Metalloproteinase-9 is increased after toluene diisocyanate exposure in the induced sputum from patients with toluene diisocyanate-induced asthma

BACKGROUND AND OBJECTIVE: Persistent asthma symptoms are associated with airway inflammation and remodeling, which may be mediated through metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP). The aim of this study was to evaluate MMPs and TIMP involvement in toluene diisocyanate (TDI)-induced asthma. MATERIALS AND METHOD: Induced sputum was collected in eight newly diagnosed TDI-induced asthma subjects (group I) before and 7 h after the TDI and placebo challenges and in 12 subjects with TDI-induced occupational asthma diagnosed 5 years previously with persistent asthma symptoms (group II). Sera was collected in group I at diagnosis, and in group II, they were collected at the time of the study. 12 nonasthmatic healthy subjects were enrolled as controls. MMP-9, MMP-2 and TIMP-1 levels in both sputum and serum were measured by enzyme-linked immunosorbent assay (ELISA). Gelatinase activity in the sputum was confirmed by zymographic analysis. RESULTS: The serum TIMP-1 level was significantly higher in asthma patients than in healthy controls (P = 0.01), while MMP-9 level was significantly lower in asthmatic patients (P = 0.03). There was no significant difference in MMP-2 level (P = 0.27). MMP-9 level in the sputum was significantly increased after the TDI challenges (P = 0.01). TIMP-1 level in sputum tended to increase after TDI challenges, but no statistical significance was noted (P = 0.09). MMP-9 and MMP-9/TIMP-1 levels in the sputum were significantly higher in group II than in group I (P = 0.04, P = 0.02) with no significant difference in TIMP-1 level. Minimal amount of MMP-2 was found in sputum. Zymography demonstrated that MMP-9 level increased and active form of MMP-9 was generated after the TDI bronchoprovocation test. CONCLUSION: TDI exposure leads to overproduction of MMP-9, which may induce airway inflammation and remodeling, and then contribute to persistent asthmatic symptoms in TDI-induced asthma.