|
KMID : 0869420170150010053
|
|
Journal of Jeahan Oriental Medical Academy
2017 Volume.15 No. 1 p.53 ~ p.71
|
|
|
Inhibitory Mechanism of Fritillaria thunbergii Miquel on Melanin Synthesis in B16F10 Melanoma Cells
|
|
Lee Soo-Min
|
|
|
Abstract
|
|
|
Background : Melanin, the pigment produced by melanocytes, is closely involved in protection against exposure to UV radiation. However, excessive deposition of melanin can lead to hyperpigmentations. Moreover, ROS activates tyrosinase and promotes melanin syntesis in melanocytes. Thus, free radical scavengers are regarded to be anti-melanogenesis agents.
Objective : The purpose of present study is to determine the anti-melanogenic effects of Fritillaria thunbergii Miq. in murine B16F10 melanoma cells as well as its underlying mechanisms.
Methods : In the present study, the effects of Fritillaria thunbergii Miq. on free radicals scavenging activity using DPPH assay and ABTS assay, and on cytotoxicity through MTT assay in B16F10 melanoma cells were examined. Also, the down-regulatory effects of Fritillaria thunbergii Miq. on tyrosinase activities under the conditions of cellular and non-cellular states, and on melanin production derived from B16F10 melanoma cells were measured. Protein levels of TRP-1, TRP-2, MITF, tyrosinase and PKA/CREB signaling pathway were examined by Western blotting. PI3K/Akt signaling pathway, known as anti-melanogenic signaling, was also determined by Western blot analysis to detect its proteins expression.
Results : Fritillaria thunbergii Miq. had significant scavenging capacities of DPPH and ABTS radicals. Fritillaria thunbergii Miq. inhibited the tyrosinase activities in both cellular and non-cellular conditions, and also strongly reduced melanin formation in B16F10 melanoma cells. In addition, Fritillaria thunbergii Miq. reduced the protein levels of TRP-1, TRP-2, MITF, Tyrosinase, p-PKA and p-CREB in α-MSH-stimulated B16F10 melanoma cells. However, Fritillaria thunbergii Miq. did not impact on the protein expression of p-PI3K and p-Akt in α-MSH-stimulated B16F10 melanoma cells.
Conclusion : Fritillaria thunbergii Miq. blocks the PKA/CREB signaling pathway, and consequently reduces expression of MITF and melanogenic enzyme, resulting in decrease of melanin production. Also, Fritillaria thunbergii Miq. has strong antioxidant effects. Taken together, these findings suggest that Fritillaria thunbergii Miq. inhibits melanin synthesis in B16F10 melanoma cells. Fritillaria thunbergii Miq. could be a natural medicine to treat the hyperpigmentations.
|
|
|
KEYWORD
|
|
|
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|
|