- 作者: Li-Chen Wu, Yu-Yun Lin, Szu-Yen Yang, Yu-Ting Weng and Yi-Ting Tsai
- 作者服務機構: Department of Applied Chemistry, National Chi Nan University, Taiwan, R.O.C.
- 中文摘要: --
- 英文摘要:
Background:
Pigmentation is one of the essential defense mechanisms against oxidative stress or UV
irradiation; however, abnormal hyperpigmentation in human skin may pose a serious
aesthetic problem. C-phycocyanin (Cpc) is a phycobiliprotein from spirulina and functions as
an antioxidant and a light harvesting protein. Though it is known that spirulina has been used
to reduce hyperpigmentation, little literature addresses the antimelanogenic mechanism of
Cpc. Herein, we investigated the rationale for the Cpc-induced inhibitory mechanism on
melanin synthesis in B16F10 melanoma cells.
Methods: Cpc-induced inhibitory effects on melanin synthesis and tyrosinase expression
were evaluated. The activity of MAPK pathways-associated molecules such as MAPK/ERK
and p38 MAPK, were also examined to explore Cpc-induced antimelanogenic mechanisms.
Additionally, the intracellular localization of Cpc was investigated by confocal microscopic
analysis to observe the migration of Cpc.
Results: Cpc significantly (P<0.05) reduced both tyrosinase activity and melanin production
in a dose-dependent manner. This phycobiliprotein elevated the abundance of intracellular
cAMP leading to the promotion of downstream ERK1/2 phosphorylation and the subsequent
MITF (the transcription factor of tyrosinase) degradation. Further, Cpc also suppressed the
activation of p38 causing the consequent disturbed activation of CREB (the transcription
factor of MITF). As a result, Cpc negatively regulated tyrosinase gene expression resulting in
the suppression of melanin synthesis. Moreover, the entry of Cpc into B16F10 cells was
revealed by confocal immunofluorescence localization and immunoblot analysis.
Conclusions: Cpc exerted dual antimelanogenic mechanisms by upregulation of
MAPK/ERK-dependent degradation of MITF and downregulation of p38 MAPK-regulated
CREB activation to modulate melanin formation. Cpc may have potential applications in biomedicine, food, and cosmetic industries. - 中文關鍵字: --
- 英文關鍵字: C-phycocyanin, antimelanogenesis, CREB, MITF, MAPK/ERK, p38 MAPK