Protective effects of myricetin against ultraviolet-B-induced damage in human keratinocytes.
Myricetin is a flavonoid similar to quercetin, which is commonly found in natural foods such as berries, vegetables, teas, wine, and herbs. It is considered to be an antioxidant which is capable of quenching photoaging-causing free radicals within the skin. In this study, we investigated the mechanisms underlying protective effect of myricetin on ultraviolet-B (UVB)-induced damage to keratinocytes. We found that myricetin concentration-dependently attenuated UVB-induced keratinocyte death as determined by a cell viability assay. Pretreatment with myricetin also reduced the UVB-induced malondialdehyde level. Moreover, UVB-induced H(2)O(2) generation in keratinocytes was inhibited by myricetin according to flow cytometry, suggesting that myricetin can act as a free radical scavenger when keratinocytes experience photodamage. Furthermore, UVB-induced activation of c-jun-NH(2) terminal kinase (JNK) in keratinocytes was inhibited by myricetin. UVB-induced pre-G(1) phase arrest leading to apoptotic changes in keratinocytes was blocked by myricetin. Taken together, the protective mechanisms of keratinocyte by myricetin against UVB-induced photodamage occur by the inhibition of UVB-induced intracellular hydrogen peroxide production, lipid peroxidation and JNK activation. Therefore, myricetin is suitable for further development as an anti-aging agent for skin care.
School of Medicine, Fu-Jen Catholic University, Taipei Hsien, Taiwan.
Jheng-Hua
JH
Huang
Chieh-Chen
CC
Huang
Jia-You
JY
Fang
Cheng
C
Yang
Chi-Ming
CM
Chan
Nan-Lin
NL
Wu
Shung-Wen
SW
Kang
Chi-Feng
CF
Hung
D016923:Cell Death / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis / Q000235:genetics; D004789:Enzyme Activation / Q000187:drug effects; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005419:Flavonoids / Q000494:pharmacology*; D005434:Flow Cytometry; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D015603:Keratinocytes / Q000187:drug effects* / Q000473:pathology / Q000528:radiation effects*; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D017382:Reactive Oxygen Species / Q000378:metabolism; D013473:Sunscreening Agents; D013778:Tetrazolium Salts; D013844:Thiazoles; D014466:Ultraviolet Rays; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
D005419:Flavonoids; D017382:Reactive Oxygen Species; D013473:Sunscreening Agents; D013778:Tetrazolium Salts; D013844:Thiazoles; C040015:myricetin; D004247:DNA; D006861:Hydrogen Peroxide; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C022616:thiazolyl blue