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bioRxiv · 10.1101/2021.04.26.441423

The Effects of Phenolic Compounds Isolated from Chinese Herbal Medicine Rhodiola Rosea on Preventing Photoaging of Keratinocytes

Toh, W. H.·Clapper, J. C.·Hsu, C.-C.·Chen, C.-B.·Lee, H.-e.·Chung, W.-H.
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Abstract

Among the many health benefits Chinese herbal medicine (CHM) presents, anti-aging is of special interest (Shen, Jiang, Yang, Wang, & Zhu, 2017; Zhao & Luo, 2017). Reported to possess anti-aging effects, the CHM Rhodiola rosea L., known colloquially as the "golden root", has been widely incorporated in various drinks, daily supplements, and even cosmetics. This study investigates the effects of commercial R. rosea extracts and natural R. rosea roots on preventing UV-induced photoaging of the skin and correlates such effects with the composition of active ingredients in the extracts. To simulate the photoaging process, drug treated HaCaT cells were exposed to UVA and UVB radiation. The pharmacological anti-aging effects of R. rosea extracts were evaluated qualitatively and quantitatively through confocal immunofluorescence images with {gamma}-H2A.X marker and telomerase activity assay (Telo TAGGG Telomerase PCR-ELISA). Preparatory thin layer chromatography and high-performance liquid chromatography were performed to isolate and quantify active ingredients. Cultured HaCaT cells showed morphological change after exposure to both UVA (>15.0 J) and UVB (>2000 mJ). The photoaging of keratinocytes was rescued by pretreating cells with R. rosea extracts as well as salidroside and rosavin active ingredients (P < 0.05). R. rosea-treated cells were characterized by increased telomerase activity and fewer {gamma}-H2A.X foci compared to that of the control. Extracts with better preventative effects contained higher salidroside and rosavin content. The findings in this study reaffirm R. roseas efficacy as an anti-aging remedy and provide a basis for CHMs integration into the mainstream of global healthcare.

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Toh, W. H., Clapper, J. C., Hsu, C.-C., Chen, C.-B., Lee, H.-e., Chung, W.-H.. 2021-04-26. The Effects of Phenolic Compounds Isolated from Chinese Herbal Medicine Rhodiola Rosea on Preventing Photoaging of Keratinocytes. https://doi.org/10.1101/2021.04.26.441423

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