title: Protective Effect of Garlic on Cellular Senescence in UVB-Exposed HaCaT Human Keratinocytes.
abstract: Ultraviolet (UV) irradiation generates reactive oxygen species (ROS) in the cells, which induces the cellular senescence and photoaging. The present study investigated the protective effects of garlic on photo-damage and cellular senescence in UVB-exposed human keratinocytes, HaCaT cells. An in vitro cell free system was used to examine the scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals and nitric oxide (NO). The effect of garlic extract on ROS formation, MMP-1 protein and mRNA expressions, cytokines such as interleukin (IL)-1β and IL-6, senescence associated-β-galactosidase (SA-β-gal) activity, and silent information regulator T1 (SIRT1) activity were determined in UVB-irradiated HaCaT cells. Garlic exhibited strong DPPH radical and NO scavenging activity in cell free system exhibiting IC50 values of 2.50 mg/mL and 4.38 mg/mL, respectively. Garlic pretreatment attenuated the production of UVB-induced intracellular ROS. MMP-1 level, which has been known to be induced by ROS, was dramatically elevated by UVB irradiation, and UVB-induced MMP-1 mRNA and protein expressions were significantly reduced by garlic treatment (50 µg/mL) comparable to those of UV-unexposed control cells. UV-induced pro-inflammatory cytokine productions (IL-6 and IL-1β) were significantly inhibited by pretreatment with garlic in a dose-dependent manner. SA-β-gal activity, a classical biomarker of cellular senescence, and SIRT1 activity, which has attracted attention as an anti-aging factor in recent years, were ameliorated by garlic treatment in UV-irradiated HaCaT cells. The present study provides the first evidence of garlic inhibiting UVB-induced photoaging as a result of augmentation of cellular senescence in HaCaT human keratinocytes.
authors.affiliation: Department of Food &amp; Biotechnology, Hanseo University, Haemi-Myun, Seosan, Chungnam 356-706, Korea. hkkim111@dreamwiz.com.
authors.forename: Hye Kyung
authors.initials: HK
authors.lastname: Kim
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D002461:Cell Line, Transformed; D016922:Cellular Senescence / Q000528:radiation effects; D016207:Cytokines / Q000037:antagonists & inhibitors / Q000378:metabolism; D019587:Dietary Supplements; D016166:Free Radical Scavengers / Q000378:metabolism*; D005737:Garlic / Q000737:chemistry; D005786:Gene Expression Regulation / Q000528:radiation effects; D006801:Humans; D015603:Keratinocytes / Q000276:immunology / Q000378:metabolism* / Q000528:radiation effects; D020781:Matrix Metalloproteinase 1 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D010936:Plant Extracts / Q000378:metabolism*; D018517:Plant Roots / Q000737:chemistry; D012333:RNA, Messenger / Q000378:metabolism; D011837:Radiation-Protective Agents / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000037:antagonists & inhibitors / Q000378:metabolism; D056564:Sirtuin 1 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015595:Skin Aging / Q000528:radiation effects; D014466:Ultraviolet Rays / Q000009:adverse effects; D001616:beta-Galactosidase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism
chemical_list: D015415:Biomarkers; D016207:Cytokines; D016166:Free Radical Scavengers; D010936:Plant Extracts; D012333:RNA, Messenger; D011837:Radiation-Protective Agents; D017382:Reactive Oxygen Species; C061901:GLB1 protein, human; D001616:beta-Galactosidase; D020781:Matrix Metalloproteinase 1; C447939:SIRT1 protein, human; D056564:Sirtuin 1
keywords: HaCaT cells; MMP-1; SA-β-gal; SIRT1; UVB irradiation; garlic; pro-inflammatory cytokine; senescence