溃疡性结肠炎大鼠结肠黏膜中MMP-3和PPAR-γ的表达及其意义

The significance and expressions of MMP-3 and PPAR-γ in colonic mucosa of rats with UC

目的检测基质金属蛋白酶-3(matrix metalloproteinases-3,MMP-3)及过氧化物酶体增殖物激活受体-γ(peroxisome prolif-erator-activated receptor-γ,PPAR-γ)在溃疡性结肠炎大鼠结肠黏膜中的表达情况,探讨二者在溃疡性结肠炎(ulcerative colitis,UC)发病机制中的作用。方法运用复合法制备UC大鼠模型,应用免疫组化Elivision法检测模型组和正常对照组大鼠结肠黏膜中MMP-3和PPAR-γ表达,并分析其与病理组织学分级关系。结果模型组和正常对照组大鼠结肠黏膜中MMP-3阳性表达率分别为90%(18/20)和55%(11/20),两者差异有统计学意义(P=0.013)。MMP-3的表达在UC大鼠Ⅰ级、Ⅱ级、Ⅲ级分别为74.79±7.75、88.07±7.05、98.77±6.87;UC大鼠Ⅰ级、Ⅱ级、Ⅲ级两两比较MMP-3差异有统计学意义。PPAR-γ在模型组大鼠结肠上皮中阳性表达率为35%(7/20),在正常大鼠结肠上皮中阳性表达率为80%(16/20),两者差异有统计学意义(P=0.004)。UC大鼠Ⅰ级、Ⅱ级、Ⅲ级PPAR-γ的表达分别为74.09±13.76、49.25±10.86、11.76±6.12;UC大鼠Ⅰ级、Ⅱ级、Ⅲ级两两比较PPAR-γ差异有统计学意义(P<0.05)。UC大鼠结肠黏膜中MMP-3表达与PPAR-γ表达呈负相关(rs=-0.454,P=0.044)。MMP-3在UC大鼠结肠黏膜中呈过度表达,并与病理组织学分级呈正相关;UC大鼠结肠黏膜中PPAR-γ表达明显下降,且与病理组织学分级呈负相关。结论MMP-3与PPAR-γ不同表达在UC发病机制中可能起协同作用,二者联合检测有可能成为UC临床诊断及评估病理组织学分级的监测指标。

Objective To detect expressions of MMP-3 and PPAR-γ in colonic mucosa of rats with UC,and to explore the role of them in the carcinogenesis of UC. Methods Compound method was used to make models of rats with UC.Expressions of MMP-3 and PPAR-γ in colonic mucosa of rats in model group and control group were detected by immunohistochemical Elivision method,and the relationship with histopathologic stage was analyzed. Results The positive expression rates of MMP-3 in colonic mucosa of model group and control group were 90%（18/20） and 55%（11/20） respectively,the expression of MMP-3 in colonic epithelium of model group was significantly higher than that in control group,the difference was significant（P=0.013）.The expressions of MMP-3 in three stages（Ⅰstage,Ⅱstage,Ⅲstage） of rats with UC were 74.79±7.75,88.07±7.05,98.77±6.87 respectively;there were significant differences among three stages.The positive expression rates of PPAR-γ in colonic mucosa of model group and control group were 35%（7/20） and 80%（16/20）,there was significantly different between them（P=0.004）.The expressions of PPAR-γ in three stages（Ⅰstage,Ⅱstage,Ⅲstage） of rats with UC were 74.09±13.76,49.25±10.86,11.76±6.12 respectively;there were statistical differences among them（P〈0.05）.There was a negative correlation between the expressions of MMP-3 and PPAR-γ in colonic mucosa of rats with UC（rs=-0.454,P=0.044）.MMP-3 in colonic mucosa of rats with UC was over expressed,and it was a positive correlation with the histopathologic stage;PPAR-γ in colonic mucosa of rats with UC obviously decreased,and it was a negative correlation with the histopathologic stage. Conclusion The different expressions of MMP-3 and PPAR-γ may cooperatively play a role in the pathogenesis and development of UC.The combined detection of MMP-3 and PPAR-γ may be a monitoring indicator for clinical diagnosis of UC and assessing the histopathologic stages.