title: Naringin protects ultraviolet B-induced skin damage by regulating p38 MAPK signal pathway.
abstract: BACKGROUND
  Naringin is a bioflavonoid and has free radical scavenging and anti-inflammatory properties.
  
  
  METHODS
  We examined the effects of naringin on skin after ultraviolet radiation B (UVB) irradiation and the signal pathways by in vitro and in vivo assay.
  
  
  RESULTS
  HaCaT cells pretreated with naringin significantly inhibited UVB induced-cell apoptosis and production of intracellular reactive oxygen species (ROS). The expressions of interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8) and cyclooxygenase-2 (COX-2) in HaCaT cells pretreated with naringin were decreased compared with the only UVB group. Also, the activation of p38 induced by UVB in HaCaT cells was reversed by naringin treatments. The inhibition function of naringin on p38 activity was more obvious than JNK. In vivo, topical treatments with naringin prevented the increase of epidermal thickness, IL-6 production, cell apoptosis and the overexpression of COX-2 in BALB/c mice skin irradiated with UVB. Naringin treatment also markedly blocked the activation of p38 in response to UVB stimulation in the mouse skin.
  
  
  CONCLUSIONS
  Naringin can effectively protect against UVB-induced keratinocyte apoptosis and skin damage by inhibiting ROS production, COX-2 overexpression and strong inflammation reactions. It seemed that naringin played its role against UVB-induced skin damage through inhibition of mitogen-activated protein kinase (MAPK)/p38 activation.
authors.affiliation: Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Ren
authors.affiliation: Department of Dermatology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, China.
authors.forename: Yuling
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China.
authors.forename: Di
authors.initials: D
authors.lastname: Zhao
authors.affiliation: Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China.
authors.forename: Mengyu
authors.initials: M
authors.lastname: Xu
authors.affiliation: Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Li
authors.affiliation: Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China.
authors.forename: Yongyan
authors.initials: Y
authors.lastname: Dang
authors.affiliation: Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China. Electronic address: xyye@bio.ecnu.edu.cn.
authors.forename: Xiyun
authors.initials: X
authors.lastname: Ye
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002460:Cell Line; D051546:Cyclooxygenase 2 / Q000378:metabolism; D005260:Female; D044950:Flavanones / Q000494:pharmacology*; D006801:Humans; D007249:Inflammation / Q000188:drug therapy; D053583:Interleukin-1beta / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D015603:Keratinocytes / Q000187:drug effects; D020935:MAP Kinase Signaling System / Q000187:drug effects*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D017382:Reactive Oxygen Species / Q000378:metabolism; D012867:Skin / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects*; D014466:Ultraviolet Rays / Q000009:adverse effects*; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*
chemical_list: C508606:CXCL8 protein, human; D044950:Flavanones; C508585:IL1B protein, human; C508600:IL6 protein, human; D053583:Interleukin-1beta; D015850:Interleukin-6; D016209:Interleukin-8; D017382:Reactive Oxygen Species; C577686:interleukin-6, mouse; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D048051:p38 Mitogen-Activated Protein Kinases; C005274:naringin
keywords: COX-2; Naringin; UVB; p38