Tropical Journal of Pharmaceutical Research

Original Research Article | OPEN ACCESS

Inhibitory Effects of (-)-Epigallocatechin-3-gallate on Melanogenesis in Ultraviolet A-Induced B16 Murine Melanoma Cell

Yue-Rong Liang¹, Suyoung Kang¹, Li Deng¹, Li-Ping Xiang², Xin-Qiang Zheng¹

¹Zhejiang University Tea Research Institute, Hangzhou 310058; ²Guizhou Tea and Tea Products Quality Supervision and Inspection Center, Zunyi 563100, China.

For correspondence:- Xin-Qiang Zheng Email: yrliang@zju.edu.cn Tel:+8657188982704

Received: 31 August 2014 Accepted: 23 October 2014 Published: 24 November 2014

Citation: Liang Y, Kang S, Deng L, Xiang L, Zheng X. Inhibitory Effects of (-)-Epigallocatechin-3-gallate on Melanogenesis in Ultraviolet A-Induced B16 Murine Melanoma Cell. Trop J Pharm Res 2014; 13(11):1825-1831 doi: 10.4314/tjpr.v13i11.8

© 2014 The authors.
This is an Open Access article that uses a funding model which does not charge readers or their institutions for access and distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0) and the Budapest Open Access Initiative (http://www.budapestopenaccessinitiative.org/read), which permit unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited..

Abstract

Purpose: To investigate the anti-melanogenesis effect of green tea compound, (-)-epigallocatechin-3-gallate (EGCG), on B16 murine melanoma cell irradiated by ultraviolet A (UVA) in the search for natural skin-lightening alternative agents.

Methods: B16 murine melanoma cells by UVA (9.0 J/cm²) for 0 to 32 min and then incubated in Dulbecco's Modified Eagle's Medium (DMEM) with EGCG (0-200 μg/mL) for 2 days. Cell viability was determined by MTT method and cell protein was quantified using a PA102 Bradford protein assay kit. Activity of tyrosinase (TRY) was determined based on the oxidation rate of 3,4-dihydroxy phenylalanine (DOPA). The ultra-structure of the melanosomes was observed by transmission electron microscopy (TEM).

Results: TRY activity and melanin concentration were increased to 146.70 ± 10.28 % (p < 0.05) and 157.06 ± 6.37 % (p < 0.05), respectively, by 9.0 J/cm2 UVA irradiation for 8 min, compared to blank control without UV A and EGCG. EGCG inhibited the UV A induced increase in TRY activity and melanin level, and the optimum concentration of EGCG was 25 μg/mL. TRY activity and melanin concentration were decreased to 64.71 ± 4.41 (p < 0.05) and 86.24 ± 5.15 % (p < 0.05), respectively, compared to blank (control) which was neither treated by UVA nor by EGCG. TEM showed that UVA induced the formation of melanosomes while EGCG inhibited UVA-induced melanosome maturation.

Conclusion: EGCG inhibits UVA-induced melanogenesis via suppression of TRY activity and melanosome maturation and is thus a potential alternative to melanogenesis inhibitor.

Keywords: Green tea, Catechins, Melanin, Melanosome, Tyrosinase, Cell proliferation