Involvement of microRNAs in epigallocatechin gallate-mediated UVB protection             in human dermal fibroblasts.
The green tea polyphenol epigallocatechin-3-gallate (EGCG) is a potent anti-oxidant             and anticancer compound. Recently, EGCG-mediated UVB photoprotection was reported             in normal human dermal fibroblasts (NHDFs); however, the molecular mechanism underlying             this process remains unknown. Thus, we investigated the EGCG-specific microRNAs             (miRNAs) involved in the UVB protective response in NHDFs. WST-1 assays confirmed             that low doses (<50 µM) of EGCG were non-cytotoxic and capable of recovering             NHDF cell viability following UVB irradiation up to 83.7% compared to the control             cells. Microarray analysis identified several miRNAs that were upregulated and             downregulated significantly in this UVB protective response, with downregulated             miRNAs outnumbering the upregulated ones. Bioinformatic studies, including miRNA             target gene prediction and gene ontology analysis, revealed that the EGCG-specific             miRNAs may control genes involved in transcription regulation and inhibition of             apoptosis, but not MAPK activation, in NHDFs. Therefore, these results suggest             that EGCG may serve as a potential natural photoprotective agent against UVB-mediated             damage in NHDFs by altering specific miRNA expression.
Korea Institute for Skin and Clinical Sciences, Seoul 143-701, Republic of Korea.
In-Sook
IS
An
Sungkwan
S
An
Seyeon
S
Park
Sung Nae
SN
Lee
Seunghee
S
Bae
D000975:Antioxidants / Q000494:pharmacology; D014408:Biomarkers, Tumor / Q000235:genetics; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D002478:Cells, Cultured; D020405:Dermis / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D020869:Gene Expression Profiling; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010766:Phosphorylation / Q000187:drug effects; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D014466:Ultraviolet Rays
D000975:Antioxidants; D014408:Biomarkers, Tumor; D035683:MicroRNAs; D011837:Radiation-Protective Agents; D002392:Catechin; C045651:epigallocatechin gallate; D020928:Mitogen-Activated Protein Kinases