In the case of diabetic wounds, MMP-1, MMP-2, and MMP-9 have roles in the re-epithelialization of wounds through the migration of keratinocytes (which is further explained below) [29], and the hypoxic and inflammatory environment of wounds of patients with DM is accompanied by an increase in reactive oxygen species (ROS) and an overproduction of MMP-9, which generates damage to the tissue and leads to poor wound healing [111]. This evidence concerns the gene MMP2 and diabetes mellitus.