Kuroda Tadahide, Yoshida Yutaka, Kamiie Junichi, Kovalenko Pavel, Nameta Masaaki, Fujinaka Hidehiko, Yaoita Eishin, Endo Tetsuya, Ishizuka Shunji, Nakabayashi Kimimasa, Yamada Akira, Nagasawa Toshihiko, Yamamoto Tadashi
Department of Structural Pathology, Institute of Nephrology, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan.
Clin Exp Nephrol. 2004 Sep;8(3):206-15. doi: 10.1007/s10157-004-0289-8.
Matrix metalloproteinase (MMP)-9, a member of the MMP family with specificity towards type IV collagen, is implicated in the turnover of the extracellular matrix in the kidney. To elucidate its physiological and pathophysiological significance, we examined the expression and localization of MMP-9 in the normal kidney and the changes in these features during the course of anti-glomerular basement membrane (GBM) glomerulonephritis induced in WKY rats, along with the changes in these features of tissue inhibitor of metalloproteinase 1 (TIMP-1) and MMP-2.
The expression of MMP-9, TIMP-1 and MMP-2 mRNA was quantified by ribonuclease protection assay, and the gelatinolytic activities of MMP-9 and MMP-2 were evaluated by gelatin zymography. The localization of MMP-9 was visualized by immunohistochemistry and immunofluorescence microscopy.
The ribonuclease protection assay indicated the almost exclusive expression of MMP-9 mRNA in the glomerulus of normal kidneys. Immunohistochemistry and double-label immunofluorescence microscopy showed that MMP-9 was localized in the mesangial cells. During the course of anti-GBM glomerulonephritis, the expression of MMP-9 mRNA in glomeruli increased on day 1, peaked on days 3 to 7, and then decreased on day 14. The change in MMP-9 mRNA expression was accompanied by parallel changes in the gelatinolytic activity of the active form of MMP-9, TIMP-1 mRNA expression, and MMP-9 immunoreactivity in mesangial cells. In contrast, glomerular MMP-2 mRNA expression and its activity increased after the decline of MMP-9.
MMP-9 mRNA was predominantly expressed in the glomerulus in normal rat kidneys and MMP-9 was present in the mesangium. The MMP-9 mRNA expression increased in the glomerulus 3 to 7 days after the induction of anti-GBM glomerulonephritis in WKY rats, in parallel with the development of abnormal glomerular histology and injury, suggesting a role of MMP-9 in proteolysis of the GBM during glomerulonephritis. MMP-2 may participate in the later phase of the nephritis.
基质金属蛋白酶（MMP）-9是MMP家族中对IV型胶原具有特异性的成员，与肾脏细胞外基质的更新有关。为阐明其生理和病理生理意义，我们检测了正常肾脏中MMP-9的表达和定位，以及在WKY大鼠诱导的抗肾小球基底膜（GBM）肾小球肾炎病程中这些特征的变化，同时检测了金属蛋白酶组织抑制剂1（TIMP-1）和MMP-2这些特征的变化。
通过核糖核酸酶保护试验定量MMP-9、TIMP-1和MMP-2 mRNA的表达，并通过明胶酶谱法评估MMP-9和MMP-2的明胶水解活性。通过免疫组织化学和免疫荧光显微镜观察MMP-9的定位。
核糖核酸酶保护试验表明，MMP-9 mRNA在正常肾脏肾小球中几乎呈特异性表达。免疫组织化学和双标记免疫荧光显微镜显示，MMP-9定位于系膜细胞。在抗GBM肾小球肾炎病程中，肾小球中MMP-9 mRNA的表达在第1天增加，在第3至7天达到峰值，然后在第14天下降。MMP-9 mRNA表达的变化伴随着MMP-9活性形式的明胶水解活性、TIMP-1 mRNA表达以及系膜细胞中MMP-9免疫反应性的平行变化。相比之下，MMP-9下降后肾小球MMP-2 mRNA表达及其活性增加。
MMP-9 mRNA在正常大鼠肾脏的肾小球中主要表达，MMP-9存在于系膜中。在WKY大鼠诱导抗GBM肾小球肾炎后3至7天，肾小球中MMP-9 mRNA表达增加，与肾小球组织学异常和损伤的发展平行，提示MMP-9在肾小球肾炎期间GBM的蛋白水解中起作用。MMP-2可能参与肾炎的后期阶段。
