Publications by authors named "Sung-Mok Beak"

The volatile extract from dried pericarp of Zanthoxylum schinifolium that was obtained by simultaneous distillation with dichloromethane and water was composed of 29.9% geranyl acetate, 15.8% citronella, 15.

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Matrix metalloproteinases (MMPs), a key component in photoaging of the skin due to exposure to ultraviolet A, appear to be increased by ultraviolet A irradiation-associated generation of reactive oxygen species. In this study, we investigated the effects of synthetic rutaecarpine, which is also found in Evodia rutaecarpa, on the ultraviolet A-induced changes in the expression of gelatinases: matrix metalloproteinase (MMP)-2 and MMP-9 using HaCaT human keratinocytes as a model cellular system. Ultraviolet A irradiation of HaCaT cells increased the gelatinolytic activities of MMP-2 and MMP-9, which was significantly suppressed by the pretreatment with rutaecarpine.

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The detrimental effects of ultraviolet B (UVB) irradiation have been connected with the enhanced generation of reactive oxygen species (ROS) by UVB. However, the exact source of ROS produced by UVB has not been clearly revealed yet. In this study, we determined the source of ROS production and its role in the UVB-induced activation of nuclear factor (NF)-kappaB in HaCaT human keratinocytes.

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Premature aging of the skin (photoaging) is a well-documented consequence of exposure to ultraviolet-A (UVA). Enhanced generation of reactive oxygen species and induction of matrix metalloproteinases (MMPs) appear to be the most important components of UVA-modulated signal transduction pathways, ultimately leading to photoaging. In this study, we investigated the effects of asiatic acid and ursolic acid, triterpene compounds, on the UVA-modulated signaling pathways using HaCaT human keratinocytes as a model cellular system.

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Synopsis of recent research by authors named "Sung-Mok Beak"

  • - Sung-Mok Beak's research primarily focuses on the mechanisms through which reactive oxygen species (ROS) are generated in human cells, particularly in response to ultraviolet (UV) radiation and their implications for cellular processes such as apoptosis and photoaging.
  • - The findings indicate that various compounds, including essential oils from Zanthoxylum schinifolium and specific alkaloids like rutaecarpine, can modulate ROS levels and impact the expression of matrix metalloproteinases (MMPs) in human keratinocytes, potentially offering therapeutic benefits against UV-induced damage.
  • - Beak's work provides insights into the pathways involved in skin damage from UV exposure, highlighting the roles of NADPH oxidase, cyclooxygenase, and specific triterpenes in mediating these effects, thereby contributing to the understanding of skin photoaging and related cellular responses.