Shiho Yawaka
Kana Kikuchi
Masamichi Ishigami
Masanori Okada
SPTM R&D Australia, GRIDD Griffith University

Hitoshi Masaki
Tokyo University of Technology

[Abstract]
We are modern people who live in stressful physical and psychological circumstances. Some recent studies have demonstrated that psychological conditions closely influence the function of the skin. In this study, we identified the adverse actions of cortisol on the differentiation of keratinocytes and improved the skin condition using Gingko biloba leaf extract (GLE). Cortisol suppressed mRNA expression of filaggrin, and involucrin etc., and elevated the intracellular oxidative stress via glucocorticoid receptors in NHEKs. Meanwhile, GLE restored the cortisol-induced down-regulations of mRNA expression of FLG, and INV etc. in NHEKs, demonstrating that GLE improved the altered terminal differentiation of the epidermis. Furthermore, our results confirmed that GLE increased the intracellular antioxidative defenses, including superoxide dismutase (SOD) and catalase (CAT) activities, by activating Nrf2, and suppressed the cortisol-induced increase in intracellular ROS. Thus, it is concluded that GLE is effective candidate on improvement or prevention of psychological stress-induced rough skin.