Matrix metalloproteinase-9 (MMP-9) belongs to the MMP family and has been widely investigated. Excessive MMP-9 expression can enhance extracellular matrix degradation and promote plaque instability. Studies have demonstrated that MMP-9 levels are higher in vulnerable plaques than in stable plaques. Additionally, several human studies have demonstrated that MMP-9 may be a predictor of atherosclerotic plaque instability and a risk factor for future adverse cardiovascular and cerebrovascular events. MMP-9 deficiency or blocking MMP-9 expression can inhibit plaque inflammation and prevent atherosclerotic plaque instability. All of these results suggest that MMP-9 may be a useful predictive biomarker for vulnerable atherosclerotic plaques, as well as a therapeutic target for preventing atherosclerotic plaque instability. In this review, we describe the structure, function, and regulation of MMP-9. We also discuss the role of MMP-9 in predicting and preventing atherosclerotic plaque instability.

中文翻译：

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基质金属蛋白酶9在动脉粥样硬化斑块不稳定性中的作用

基质金属蛋白酶 9 (MMP-9) 属于 MMP 家族，已被广泛研究。MMP-9 过度表达可增强细胞外基质降解并促进斑块不稳定性。研究表明，易损斑块中的 MMP-9 水平高于稳定斑块。此外，几项人体研究表明，MMP-9 可能是动脉粥样硬化斑块不稳定的预测因子，也是未来不良心脑血管事件的危险因素。MMP-9缺乏或阻断MMP-9表达可抑制斑块炎症并防止动脉粥样硬化斑块不稳定。所有这些结果表明，MMP-9 可能是易损动脉粥样硬化斑块的有用预测生物标志物，以及预防动脉粥样硬化斑块不稳定的治疗靶点。在这次审查中，我们描述了 MMP-9 的结构、功能和调节。我们还讨论了 MMP-9 在预测和预防动脉粥样硬化斑块不稳定中的作用。