Camellioside A, isolated from Camellia japonica flowers, attenuates UVA‑induced production of MMP‑1 in HaCaT keratinocytes via suppression of MAPK activation

Abstract

Ultraviolet (UV) radiation is responsible for various damages to the skin, collectively referred to as photoaging. A key UV-induced effect on the skin is excessive degradation of collagen and related structural abnormalities. Camellia japonica is a flowering plant with cosmeceutical properties. In the present study, Camellioside A (CMDA), a triterpene saponin, was investigated for its effects against UVA-induced photoaging in HaCaT keratinocytes. CMDA was analyzed to determine its attenuating effects against UVA-induced overproduction of the collagen degradation enzyme, matrix metalloproteinase-1 (MMP-1), in UVA-irradiated immortalized human HaCaT keratinocytes. UVA irradiation significantly increased MMP-1 release from keratinocytes in addition to suppressing type Iα1 pro-collagen production. Treatment with CMDA reversed the effects of UVA irradiation on the production of MMP-1 and type Iα1 pro-collagen. UVA irradiation also stimulated the activation of p38, ERK and JNK mitogen-activated protein kinases (MAPKs) and their downstream transcription factor activator protein 1 (a heterodimer of c-Fos and c-Jun). MAPK activation and consequent phosphorylation of c-Fos and c-Jun were also inhibited by CMDA treatment. In conclusion, the present study indicated that CMDA may have potential antiphotoaging properties due to suppression of UVA-mediated MMP-1 production.