Related Experiment Video
Updated: Mar 19, 2026
12:37
Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
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Afzelin positively regulates melanogenesis through the p38 MAPK pathway
Eunsun Jung1, Jin Hee Kim2, Mi Ok Kim3
1Biospectrum Life Science Institute, Seongnam City, 132-16, Gyunggi Do, Republic of Korea.
Chemico-Biological Interactions
|June 12, 2016
Summary
Afzelin enhances skin pigmentation by boosting melanin production and tyrosinase activity. This process involves upregulating microphthalmia-associated transcription factor (MITF) via p38 MAPK activation, suggesting potential UV protection benefits.
Area of Science:
- Biochemistry
- Dermatology
- Molecular Biology
Background:
- Melanogenesis is the process of synthesizing melanin, crucial for skin protection against UV radiation and oxidative stress.
- Understanding the regulation of melanogenesis is key to developing photoprotective strategies.
Purpose of the Study:
- To investigate the effects of afzelin on melanogenesis in human epidermal melanocytes.
- To elucidate the underlying molecular mechanisms of afzelin's action on melanin production.
Main Methods:
- Human epidermal melanocytes were treated with varying concentrations of afzelin.
- Melanin content, tyrosinase activity, and the expression of key melanogenic genes (MITF, TYR, TRP-1, TRP-2) at mRNA and protein levels were analyzed.
- The role of p38 MAPK and cAMP-PKA signaling pathways was assessed.
Main Results:
- Afzelin significantly increased melanin content and tyrosinase activity in a dose-dependent manner.
- Afzelin upregulated the mRNA and protein levels of MITF, tyrosinase, and TRP-1, but not TRP-2.
- Afzelin promoted melanogenesis by upregulating MITF expression through p38 MAPK phosphorylation, independent of the cAMP-PKA pathway.
Conclusions:
- Afzelin stimulates melanogenesis by enhancing MITF gene expression via p38 MAPK activation.
- Afzelin demonstrates potential as a protective agent against UV-induced skin damage.
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