Age‐related reduction of dermal fibroblast size upregulates multiple matrix metalloproteinases as observed in aged human skin in vivo

Fragmentation of collagen fibrils, the major structure protein in skin, is a hallmark of dermal ageing. Matrix metalloproteinases (MMPs) are largely responsible for the fragmentation of collagen fibrils. To quantify gene expression of all 23 known mammalian MMPs in sun‐protected young and aged human skin in vivo and to investigate the potential mechanism underlying age‐related alteration of multiple MMPs. MMP mRNA expression levels and MMP...