Abstract
Stratifin (SFN), a member of the 14-3-3 protein family, is expressed in epidermal keratinocytes. It was reported that SFN is induced in a p53-dependent manner after DNA damage, acts as an inhibitor of cell cycle progression and is involved in apoptosis induction. It was also reported that SFN is related to collagen metabolism through regulation of expression of collagen and matrix metalloproteinase in dermal fibroblasts. However, the roles of SFN in skin aging are not clearly understood. In this study, the association of SFN with the mechanism of intrinsic skin aging was investigated. SFN mRNA expression and protein levels increased significantly in keratinocytes treated with bromodeoxyuridine (BrdU), an inducer of a senescence-like phenomenon. SFN significantly decreased filaggrin and serine palmitoyltransferase mRNA expression in epidermal keratinocytes. SFN also decreased type I collagen and hyaluronan synthase 2 mRNA expression in dermal fibroblasts. The increase of SFN mRNA expression in BrdU-treated keratinocytes was suppressed by the addition of Love-in-a-mist extract. Therefore, an increase of SFN triggered by cellular senescence may be one of the causes of alterations observed in intrinsic aging skin. In addition, Love-in-a-mist extract suppressed cellular senescence-induced increase of SFN mRNA expression and is considered to be an effective anti-aging ingredient for skin.
