Role of the matrixin MMP-2 in multicellular organization of adipocytes cultured in basement membrane components
Role of the matrixin MMP-2 in multicellular organization of adipocytes cultured in basement membrane components
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DOI：
10.1152/ajpcell.1997.272.3.c937
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发表时间：
1997-03-01
影响因子：
5.5
通讯作者：
Lynch, CJ
中科院分区：
文献类型：
--
作者：
Brown, LM;Fox, HL;Lynch, CJ
在基底膜成分凝胶中培养的原代大鼠脂肪细胞迁移并组织成大的三维多细胞簇。描述了在重组过程中观察到的总体形态变化。簇形成的速率随着大鼠年龄的增长而降低，并且在老年大鼠中受到胰岛素刺激，但在年轻大鼠中则不然。 Echistatin 是一种解整合素，以浓度依赖性方式部分抑制多细胞簇的形成（50% 抑制浓度约为 10 nM）。原始的细胞外基质最初被重塑，并最终在观察到大型多细胞簇时被破坏。这意味着正在分泌一种或多种基质降解蛋白酶。发现脂肪细胞条件培养基含有类似于72和/或类似于62kDa的二价阳离子敏感性明胶酶活性。明胶琼脂糖 4B 的这种活性的洗脱曲线与基质金属蛋白酶 2（MMP-2，一种 72-kDa 的基质蛋白，成熟形式为 62-kDa）相似，并且来自这些柱的二甲亚砜洗脱液含有 MMP-2 免疫反应性。年轻动物条件培养基中的 MMP-2 浓度和活性高于年老动物；然而，胰岛素并不影响脂肪细胞条件培养基中MMP-2的量。基质蛋白抑制剂 1,10-菲咯啉不仅可以阻断酶谱中的明胶酶活性，还可以防止细胞外基质重塑和破坏，以及脂肪细胞迁移和脂肪细胞培养物中细胞与细胞接触的形成。这些观察结果与基质蛋白 MMP-2 由脂肪细胞分泌的假设一致。虽然单独的基质蛋白活性可能不足以形成多细胞簇，但数据表明它可能在此过程中发挥必要的作用。
Primary rat adipocytes cultured in basement membrane component gels migrated and organized into large, three-dimensional, multicellular clusters. Gross morphological changes seen during this reorganization are described. The rate of cluster formation decreased with age of the rats and was stimulated by insulin in older, but not in younger rats. Echistatin, a disintegrin, partially inhibited the formation of multicellular clusters in a concentration-dependent fashion (50% inhibitory concentration approximate to 10 nM). The original extracellular matrix was initially remodeled and eventually destroyed by the time large multicellular clusters were observed. This implied that one or more matrix-degrading protease(s) were being secreted. Adipocyte-conditioned medium was found to contain a divalent cation-sensitive gelatinase activity at similar to 72 and/or similar to 62 kDa. The elution profile of this activity from gelatin-Sepharose 4B was similar to matrix metalloproteinase 2 (MMP-2, a 72-kDa matrixin with a 62-kDa mature form), and the dimethyl sulfoxide eluant from these columns contained MMP-2 immunoreactivity. MMP-2 concentration and activity were greater in conditioned medium from young than from older animals; however, insulin did not affect the amount of MMP-2 in adipocyte-conditioned media. The matrixin inhibitor 1,10-phenanthroline not only blocked gelatinase activity in zymograms but also prevented extracellular matrix remodeling and destruction, as well as adipocyte migration and the formation of cell-cell contacts in adipocyte cultures. These observations are consistent with the hypothesis that the matrixin MMP-2 is secreted by adipocytes. Whereas matrixin activity alone may not be sufficient for the formation of multicellular clusters, the data indicate that it may have a requisite role in this process.