目的 对人基质金属蛋白酶组织抑制物-1(TIMP-1)转基因小鼠肾组织内外源人TIMP-1基因的功能表型进行鉴定,为深入研究TIMP-1在肾脏疾病进展过程中的病理生理作用奠定基础。方法 3月龄野生型小鼠(n=8,正常组)和hTIMP-1转基因小鼠(n=8)肾组织石蜡切片行PAS染色,观察肾脏组织结构变化。采用Northern杂交、Western印迹方法检测两组小鼠肾组织内h/mTIMP-1、mTIMP-1、TIMP-2、TIMP-3、MMP-9、MMP-2和COLⅣa5mRNA及蛋白质表达;明胶酶谱法检测MMP-2、MMP-9的活性。反向酶谱法检测TIMP-1的活性。结果 hTIMP-1转基因小鼠与正常组小鼠相比,肾组织结构未见显著变化。与正常组小鼠相比,hTIMP-1转基因小鼠肾组织内h/mTIMP-1mRNA、蛋白表达及活性显著升高(P<0.05);TIMP-2、MMP-2mRNA和蛋白表达降低(P<0.05);MMP-9的活性增高(P〈0.05),而MMP-2的活性则降低(P<0.05)。两组小鼠mTIMP-1、TIMP-3、MMP-9和COLIVa5的mRNA表达没有显著性差异(P>0.05)。结论 外源基因在人TIMP-1转基因小鼠肾组织内稳定表达并导致MMPs/TIMPs系统发生代偿性变化。
Objective To thoroughly explore the pathophysiological roles of TIMP-1 during the progressive course of renal diseases, the study was aimed at identifying the functional phenotype of endogenous and exogenous genes in kidneys of human TIMP-1 transgenic mice. Methods Renal histological changes between 3-month-old wild type mice (n=8) and 3-month-old transgenic mice (n=8) were analyzed through PAS staining of paraffin sections. The mRNA and protein expressions of h/mTIMP-1, mTIMP-1, TIMP-2, TIMP-3, MMP-9, MMP-2, and COLⅣa5 mRNA were detected by Northern blot and Western blot. The activities of gelatinases and TIMP-1 were examined by gelatin zymography and reverse zymography, respectively. Results No difference in histological picture in kidneys was found between wild type and transgenic mice. In contrast with wild type mice, it was found that in kidneys of transgenic mice, the mRNA and protein expressions of h/mTIMP-1 and its activity were up-regulated (P〈0. 05), the mRNA and protein expressions of TIMP-2 and MMP-2 were down-regulated (P〈0. 05), and the activity of MMP-9 was up-regulated, however, the activity of MMP-2 was down-regulated (P〈0. 05). There was no significant difference in the mRNA expressions of mTIMP-1, TIMP-3, MMP-9, and COlⅣa5 between the two groups (P〉0. 05). Conclusion The transgene was expressed steadily in kidneys of human TIMP-1 transgenic mice, and it induced the compensation of MMPs/TIMPs.