Juglans mandshurica leaf extract protects skin fibroblasts from damage  by regulating the oxidative defense system.
Skin is mainly damaged by genetic and environmental factors such as ultraviolet light, xenobiotics, hormonal changes, heat, and smoking. ROS production is commonly involved in the pathogenesis of skin damage induced by these factors, causing skin aging, including wrinkling, by activating the metalloproteinases (MMP-1) that break down type I collagen (COL1A1). The walnut tree Juglans mandshurica MAX. (JM) is found in China, Siberia and Korea. JM has been reported to have various pharmacological activities, such as anti-tumor, anti-oxidative, and anti-bacterial effects. In the present study, we investigated the protective effect of JM leaf extract (JME) against oxidative stress in HS68 human skin fibroblasts. JME significantly and dose-dependently protected HS68 cells against H₂O₂-induced damage, as assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assay. Other assays demonstrated that JME protected HS68 cells by regulating ROS production and increasing levels of glutathione, heme oxygenase-1, and activated NF-E2-related factor 2. JME additionally prevented the elevation of MMP-1 and reduction of COL1A1 induced by H₂O₂. It also inhibited H₂O₂-induced phosphorylation of ERK, p38, and JNK. These results indicate that JME protects human skin fibroblasts from H₂O₂-induced damage by regulating the oxidative defense system.
Department of Life and Nanopharmaceutical Science, and Kyung Hee East-West Pharmaceutical Research Institute, Kyung Hee University, 1 Hoegi-dong, Dongdaemun-gu, Seoul 130-701, Republic of Korea.
Gunhyuk
G
Park
Dae Sik
DS
Jang
Myung Sook
MS
Oh
D002460:Cell Line; D019610:Cytoprotection; D005347:Fibroblasts / Q000187:drug effects; D005978:Glutathione / Q000378:metabolism; D051547:Heme Oxygenase-1 / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D031324:Juglans / Q000737:chemistry*; D018384:Oxidative Stress / Q000187:drug effects*; D018515:Plant Leaves / Q000737:chemistry*; D012867:Skin / Q000166:cytology / Q000187:drug effects*
D006861:Hydrogen Peroxide; C496541:HMOX1 protein, human; D051547:Heme Oxygenase-1; D005978:Glutathione