Abstract
To obtain insight into the relationship between blood capillaries in the skin and aged appearance, we developed a novel microscope for observing the capillaries in the forefront of the skin, the papillary dermis. The new device utilizes a carefully designed skin contact apparatus that controls the local flow of blood, enabling quantitative observation of the capillaries in the papillary dermis of facial skin, as well as other parts of the body. We observed and quantified capillaries on cheeks of 34 healthy female volunteers in their 20s to 50s, and found that the areal number density of capillary loops shows a decreasing trend with age. Statistical analysis of the relationship between the areal number density of capillary loops in the papillary dermis and cutaneous properties was conducted. Dullness factor, wrinkle factor, and net elasticity were found to be significantly correlated with the areal number density of capillary loops. From these results, we presumed that these capillaries play a critical role in preventing aged appearance. In order to search for materials with capillary formation potential, we established a novel co-culture in vitro system consisting of human umbilical vein endothelial cells (HUVECs) and mesenchymal stem cells (MSCs). From screening of materials in our in vitro system, we found tripeptide-1 as a novel active ingredient that stimulates capillary formation.
