【摘要】 背景:同型半胱氨酸已被证实是动脉粥样硬化发生的一个独立危险因素。目的:观察同型半胱氨酸对血管平滑肌细胞基质金属蛋白酶1及金属蛋白酶组织抑制剂1的分泌量和活性的影响。设计:自身对照观察。单位:吉林大学再生医学科学研究所病理室。材料:体外培养的鼠龄4～6周,体质量150g左右雄性Wistar大鼠的血管平滑肌细胞。大鼠由吉林大学白求恩医学部实验动物室提供。方法:实验于2001-05/2003-05在吉林大学再生医学科学研究所病理室完成。采用体外培养大鼠血管平滑肌细胞,分成5组,分别加入浓度为0(对照组),0.10,0.25,0.50和1.00mmol/L同型半胱氨酸作用48h,通过酶谱分析同型半胱氨酸对血管平滑肌细胞细胞基质金属蛋白酶1活性的影响,Western blot技术和半定量RT-PCR方法观察细胞基质金属蛋白酶1和金属蛋白酶组织抑制剂1分泌量及其mRNA的表达。主要观察指标:细胞基质金属蛋白酶1的活性,金属蛋白酶1和金属蛋白酶组织抑制剂1分泌量及其mRNA的表达。结果:①金属蛋白酶1和金属蛋白酶组织抑制剂1分泌量:半胱氨酸0.25,0.50和1.00mmol/L组金属蛋白酶1显著低于对照组(P<0.05～0.01);半胱氨酸0.10,0.25,0.50和1.00mmol/L组金属蛋白酶组织抑制剂1均高于对照组(P<0.05～0.01);②基质金属蛋白酶1活性随着半胱氨酸剂量增加而降低,0.50和1.00mmol/L组降低显著(P<0.01);③加入同型半胱氨酸4组金属蛋白酶1mRNA表达显著低于对照组(P<0.01)],半胱氨酸0.25mmol/L组金属蛋白酶组织抑制剂1mRNA高于对照组(P<0.05),0.50和1.00mmol/L组显著高于对照组(P<0.01))。结论:同型半胱氨酸通过抑制细胞基质金属蛋白酶1的分泌,抑制其酶活性,减少胶原降解而使胶原蓄积。提示同型半胱氨酸减少胶原降解可能是动脉粥样硬化的发病机制之一。更多还原

【Abstract】 BACKGROUND: Homocysteine (HCY) has been verified as an independent risk factor of atherosclerosis and atherothrombosis of cardiovascular disease. OBJECTIVE: To observe the effects of HCY on the secretion and activity of matrix metallopotinase-1 (MMP-1) and tissue inhibitors of metalloproteinase-1 (TIMP-1) in vascular smooth muscle cells (VSMCs). DESIGN: Auto-control observation. SETTING: Pathology Room, Institute of Regeneration Medical Sciences, Jilin University. MATERIALS: In vitro cultured vascular smooth muscles cells (VSMCs) of rats were obtained from male Wistar rats with the body mass of about 150 g from weeks 4-6 supplied by Laboratory of Animals, Norman Bethune Medical Sciences Division, Jilin University. METHODS: The experiment was performed at the Pathology Room, Institute of Regeneration Medical Sciences, Jilin University from May 2001 to May 2003. VSMCs of in vitro cultured rats were adopted and divided into 5 groups, 0 (control group), 0.10, 0.25, 0.50 and 1.00 mmol/L HCY were added, respectively for 48 hours. Effect of HCY on activity of MMP-1 was observed with zymography. The secretions of MMP-1 and TIMP-1 and their mRNA expressions were studied with Western blot and semi-quantitative reverse transcription polymerase chin (RT-PCR). MAIN OUTCOME MEASURES: Activity of MMP-1, secretions of MMP-1 and TIMP-1 and their mRNA expressions. RESULTS: ①Secretions of MMP-1 and TIMP-1: The secretion of MMP-1 in the 0.25, 0.50 and 1.00 mmol/L HCY groups was lower significantly than that in the control group (P < 0.05-0.01). The secretion of TIMP-1 in the 0.10, 0.25, 0.50 and 1.00 mmol/L HCY groups was higher than that in the control group (P < 0.05-0.01). ②The MMP-1 activity decreased with the increase of HCY, but reduced obviously in the 0.50 and 1.00 mmol/L HCY groups (P < 0.01). ③The expression of MMP-1 mRNA in the 4 HCY groups was lower markedly than that in the control group (P < 0.01). The expression of TIMP-1 mRNA in the 0.25 mmol/L HCY group was higher than that in the control group (P < 0.05), and it was higher remarkably in the 0.50 and 1.00 mmol/L HCY groups than that in the control group (P < 0.01). CONCLUSION: HCY can inhibit enzyme activity, decrease collagen degradation and induce collagen accumulation by inhibiting the secretion of MMP-1, which indicates that reduction of collagen degradation induced by HCY is one of the pathogenesies of atherosclerosis.更多还原