Baicalin Protects Keratinocytes from Toll-like Receptor-4 Mediated DNA Damage and Inflammation Following Ultraviolet Irradiation
| Autor: | Wei Min, Qihong Qian, Erin M. Burns, Michelle E. Chang, Israr Ahmad, Nabiha Yusuf |
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| Rok vydání: | 2015 |
| Předmět: |
Keratinocytes
DNA damage Ultraviolet Rays Pyrimidine dimer Gene mutation Biochemistry Article chemistry.chemical_compound medicine Humans Physical and Theoretical Chemistry Cells Cultured chemistry.chemical_classification Flavonoids Reactive oxygen species Toll-like receptor Anti-Inflammatory Agents Non-Steroidal General Medicine IRAK4 Cell biology Toll-Like Receptor 4 medicine.anatomical_structure chemistry Keratinocyte Reactive Oxygen Species Baicalin DNA Damage |
| Zdroj: | Photochemistry and photobiology. 91(6) |
| ISSN: | 1751-1097 |
| Popis: | UVB radiation contributes to both direct and indirect damage to the skin including the generation of free radicals and reactive oxygen species (ROS), inflammatory responses, immunosuppression, and gene mutations, which can ultimately lead to photocarcinogenesis. A plant-derived flavonoid, baicalin, has been shown to have antioxidant, anti-inflammatory, and free radical scavenging activities. Previous studies from our laboratory have shown that in murine skin, Toll like receptor-4 (TLR4) enhanced both UVB-induced DNA damage and inflammation. The aim of the current study is to investigate the efficacy of baicalin against TLR4-mediated processes in the murine keratinocyte PAM 212 cell line. Our results demonstrate that treating keratinocytes with baicalin both before and after UV radiation (100 mJ/cm2) significantly inhibited the level of intracellular ROS and decreased cyclobutane pyrimidine dimers (CPDs) and 8-Oxo-2′-deoxyguanosine (8-oxo-dG)—markers of DNA damage. Furthermore, cells treated with baicalin demonstrated an inhibition of TLR4 and its downstream signaling molecules, MyD88, TRIF, TRAF6, and IRAK4. TLR4 pathway inhibition resulted in NF-κB inactivation and down-regulation of iNOS and COX-2 protein expression. Taken together, baicalin treatment effectively protected keratinocytes from UVB-induced inflammatory damage through TLR pathway modulation. |
| Databáze: | OpenAIRE |
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