(-)-Epicatechin-3-gallate, a Green Tea Polyphenol Is a Potent Agent Against UVB-induced Damage in HaCaT Keratinocytes

Molecules

Chieh-Chen Huang¹  Wen-Bin Wu¹  Jia-You Fang²  Han-Sun Chiang¹  Shao-Kuan Chen³  Bing-Huei Chen⁴  Ying-Ting Chen¹ 

[1] School of Medicine, Fu-Jen Catholic University, Taipei, Taiwan;Pharmaceutics Laboratory, Graduate Institute of Natural Products, Chang Gung University, Kweishan, Taoyuan, Taiwan;Department of Surgery, Sijhih Cathay General Hospital, Taipei, Taiwan;Department of Nutrition and Food Sciences, Fu-Jen Catholic University, Taipei Hsien, Taiwan

关键词: ECG;    keratinocyte;    UVB;   

DOI  :  10.3390/12081845

来源: mdpi

【 摘 要 】

(-)-Epicatechin-3-gallate (ECG) is a polyphenolic compound similar to (-)-epigallocatechin-3-gallate (EGCG) which is abundant in green tea. Numerous workers have proposed that EGCG protects epidermal cells against UVB-induced damage. However, little has been known about whether ECG protects keratinocytes against UVB-induced damage. We decided to investigate the protective effects and underlying mechanisms of ECG on UVB-induced damage. Cell viability was determined by the MTT assay. Activation of ERK1/2, p38 and JNK was analyzed by Western blotting. Intracellular H₂O₂ production and DNA content was analyzed by flow cytometry. Lipid peroxidation was assayed by colorimetry. In our study, we found that ECG dose-dependently attenuated UVB-induced keratinocyte death. Moreover, ECG markedly inhibited UVB-induced cell membrane lipid peroxidation and H₂O₂ generation in keratinocytes, suggesting that ECG can act as a free radical scavenger when keratinocytes were photodamaged. In parallel, H₂O₂-induced the activation of ERK1/2, p38 and JNK in keratinocytes could be inhibited by ECG. UVB-induced pre-G₁ arrest leading to apoptotic changes of keratinocytes were blocked by ECG. Taken together, we provide here evidence that ECG protects keratinocytes from UVB-induced photodamage and H₂O₂-induced oxidative stress, possibly through inhibition of the activation of ERK1/2, p38 and JNK and/or scavenging of free radicals.

【 授权许可】

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