Abstract
Collagen fibers in the dermis consist of type I and type III collagen, and the ratio of type III/I collagen decreases with aging. This is thought to affect the physical properties of the dermis. Collagen molecules are synthesized and secreted as pro-collagen by dermal fibroblasts. Then their N- and C-propeptides are cleaved by enzymes. Consequently, collagen molecules are engaged with each other and form collagen fibers. To elucidate the reduction mechanism of the type III/I collagen ratio in collagen fibers with aging, we investigated the age-related change in type I and type III collagen propeptide cleavage enzymes. Moreover, we examined the effect of dipotassium bryonolyl succinate on meprin, a type III collagen propeptide cleavage enzyme. As a result, mRNA expression of meprin reduced with aging more significantly than BMP-1 and ADAMTS-14, type I collagen propeptide cleavage enzymes. Meprin mRNA expression was increased by dipotassium bryonolyl succinate. On the basis of these results, it was concluded that the more significant decrease of type III collagen propeptide cleavage enzyme was a cause of the decrease in the type III/I collagen ratio in collagen fibers. Since dipotassium bryonolyl succinate enhanced meprin mRNA level, it may prevent and improve age-related change in dermal physical properties to control the ratio of type III/I collagen by preventing the reduction of meprin with aging.
