Abstract
A major cause of wrinkle formation, which has a significant effect on apparent age, is a decrease in dermal extracellular matrix (ECM). Normally, ECM is always synthesized and decomposed to maintain a balance, but when decomposition becomes dominant due to aging, the amount of ECM decreases and wrinkles are formed. There is also a cascade that promotes ECM degradation by exposure to ultraviolet (UV) light. When UV causes inflammation of the skin, cytokines called chemokines are secreted at the inflamed area. When one of them, IL-8, is secreted, it promotes neutrophil migration and is also involved in activation of neutrophils infiltrating the inflamed site. When neutrophils are activated, they secrete excess neutrophil elastase, which promotes ECM degradation and wrinkle formation. We have constructed a method for evaluating the migration activity of neutrophil-like cells, and applied a yeast culture extract derived from the flower of “Sasayuri” (Lilium japonicum) to the neutrophil-like cell migration activity inhibitory effect, and ECM synthesis promoting effect, in vivo. The effect of improving wrinkles was confirmed, and the importance of controlling neutrophil migration by IL-8 in anti-wrinkle efforts was found.
