Related Experiment Video
Updated: Sep 29, 2026

Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Protective Effects of Duchesnea chrysantha Ethanol Extract Against UVB-Induced Skin Damage via Modulation of
Yerkyesh Khamit1, Lei Huang1, Yena Oh2
1Department of Biocosmetics, Sungkyunkwan University, Suwon, Republic of Korea.
Abstract:
Duchesnea chrysantha (Zoll. & Moritzi) Miq. (Rosaceae) has traditionally been used in East Asian medicine for inflammatory and skin-related disorders. This study investigated the phytochemical composition and protective effects of D. chrysantha ethanol extract (Dc-EE) against ultraviolet B (UVB)-induced skin damage. Untargeted LC-MS/MS analysis tentatively annotated various phytochemical constituents, including flavonoids and phenolic acids. Dc-EE reduced UVB-induced oxidative stress, reactive oxygen species production, and apoptosis in human keratinocytes (HaCaT) and dermal fibroblasts (HDF). It also suppressed cyclooxygenase-2 and matrix metalloproteinases (MMP-1, MMP-2, and MMP-9) in HaCaT cells while restoring collagen type I alpha 1 expression in HDF cells. In addition, Dc-EE enhanced the expression of skin barrier- and hydration-related factors, including filaggrin, transglutaminase-1, and hyaluronan synthase-2. Dc-EE attenuated UVB-induced MAPK signaling by reducing JNK, ERK, and p38 phosphorylation, together with AP-1 and NF-κB transcriptional activities. Reduced activation of transforming growth factor-β-activated kinase 1, an upstream stress-responsive regulator, was also observed. These findings indicate that Dc-EE attenuates UVB-induced cellular damage through antioxidant, anti-inflammatory, and barrier-related effects, supporting its potential for skin protection.
Related Concept Videos
Mutations
Chromosomal Alterations Are Large-Scale Mutations
While point mutations are changes in a single nucleotide in...
Nucleotide Excision Repair
Cells are regularly exposed to mutagens—factors in the environment that can damage DNA and generate mutations. UV radiation is one of the most common mutagens and is estimated to introduce a significant number of changes in DNA. These include bends or kinks in the structure, which can block DNA replication or transcription. If these errors are not fixed, the damage can cause mutations, which in turn can result in cancer or disease depending on which sequences are...
Role of Skin in Vitamin D Synthesis
The solar UV B rays (290-315 nm) are absorbed by the skin, and 7-dehydrocholesterol (provitamin D3) photolyzes it to previtamin D3, which undergoes a rapid transformation to vitamin D3(cholecalciferol).
Pigmentation
Melanin occurs in two primary forms: eumelanin that provides black and brown pigment and pheomelanin that provides red color. Dark-skinned individuals produce more melanin than those with pale...
