MMP9 and ulcer disease: MMPs are a family of zinc-dependent endopeptidases. One of their major characteristics is their ability to degrade various ECM components. They are produced by several different types of cells in the skin including fibroblasts, keratinocytes, macrophages, endothelial cells, mast cells, and eosinophils. Their activity is specifically inhibited by TIMPs [7-9]. Studies on wound healing in diabetic foot ulcers have shown that serum MMP-9 was lower in healing ulcers in contrast to non-healing ulcers after a four-week therapy [10].