title: Lemon balm extract (Melissa officinalis, L.) promotes melanogenesis and prevents UVB-induced oxidative stress and DNA damage in a skin cell model.
abstract: BACKGROUND
  Solar ultraviolet (UV) radiation is one of the main causes of a variety of cutaneous disorders, including photoaging and skin cancer. Its UVB component (280-315nm) leads to oxidative stress and causes inflammation, DNA damage, p53 induction and lipid and protein oxidation. Recently, an increase in the use of plant polyphenols with antioxidant and anti-inflammatory properties has emerged to protect human skin against the deleterious effects of sunlight.
  
  
  OBJECTIVE
  This study evaluates the protective effects of lemon balm extract (LBE) (Melissa Officinalis, L) and its main phenolic compound rosmarinic acid (RA) against UVB-induced damage in human keratinocytes.
  
  
  METHODS
  The LBE composition was determined by HPLC analysis coupled to photodiode array detector and ion trap mass spectrometry with electrospray ionization (HPLC-DAD-ESI-IT-MS/MS). Cell survival, ROS generation and DNA damage were determined upon UVB irradiation in the presence of LBE. The melanogenic capacity of LBE was also determined.
  
  
  RESULTS
  RA and salvianolic acid derivatives were the major compounds, but caffeic acid and luteolin glucuronide were also found in LBE. LBE and RA significantly increased the survival of human keratinocytes upon UVB radiation, but LBE showed a stronger effect. LBE significantly decreased UVB-induced intracellular ROS production. Moreover, LBE reduced UV-induced DNA damage and the DNA damage response (DDR), which were measured as DNA strand breaks in the comet assay and histone H2AX activation, respectively. Finally, LBE promoted melanogenesis in the cell model.
  
  
  CONCLUSIONS
  These results suggest that LBE may be considered as a candidate for the development of oral/topical photoprotective ingredients against UVB-induced skin damage.
authors.affiliation: Institute of Molecular and Cell Biology (IBMC), Miguel Hernández University (UMH), Avenida de la Universidad s/n, E-03202 Elche, Alicante, Spain.
authors.forename: Almudena
authors.initials: A
authors.lastname: Pérez-Sánchez
authors.affiliation: Institute of Molecular and Cell Biology (IBMC), Miguel Hernández University (UMH), Avenida de la Universidad s/n, E-03202 Elche, Alicante, Spain; INVITROTECNIA S.L., Santiago Grisolía 2, 28760 Tres Cantos, Madrid, Spain.
authors.forename: Enrique
authors.initials: E
authors.lastname: Barrajón-Catalán
authors.affiliation: Institute of Molecular and Cell Biology (IBMC), Miguel Hernández University (UMH), Avenida de la Universidad s/n, E-03202 Elche, Alicante, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Herranz-López
authors.affiliation: Nutrafur S.A., Camino Viejo de Pliego, km.2, 30820 Alcantarilla, Murcia, Spain; Department of Food Technology and Nutrition, Universidad Católica San Antonio, Murcia, Spain.
authors.forename: Julián
authors.initials: J
authors.lastname: Castillo
authors.affiliation: Institute of Molecular and Cell Biology (IBMC), Miguel Hernández University (UMH), Avenida de la Universidad s/n, E-03202 Elche, Alicante, Spain; CIBER (CB12/03/30038, Fisiopatología de la Obesidad y la Nutrición, CIBERobn, Instituto de Salud Carlos III), Spain. Electronic address: vmicol@umh.es.
authors.forename: Vicente
authors.initials: V
authors.lastname: Micol
mesh_terms: D000475:Alkenes / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology; D045744:Cell Line, Tumor; D002851:Chromatography, High Pressure Liquid; D002934:Cinnamates / Q000494:pharmacology; D004249:DNA Damage; D053630:Depsides / Q000494:pharmacology; D006801:Humans; D007249:Inflammation; D015603:Keratinocytes / Q000166:cytology; D008055:Lipids / Q000737:chemistry; D008544:Melanocytes / Q000187:drug effects*; D031334:Melissa / Q000737:chemistry*; D018384:Oxidative Stress; D010100:Oxygen / Q000737:chemistry; D010936:Plant Extracts / Q000494:pharmacology*; D059808:Polyphenols / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism; D012867:Skin / Q000187:drug effects / Q000378:metabolism*; D053719:Tandem Mass Spectrometry; D014466:Ultraviolet Rays; D000097123:Rosmarinic Acid
chemical_list: D000475:Alkenes; D000975:Antioxidants; D002934:Cinnamates; D053630:Depsides; D008055:Lipids; D010100:Oxygen; D010936:Plant Extracts; D059808:Polyphenols; D017382:Reactive Oxygen Species; D000097123:Rosmarinic Acid; C568740:salvianolic acid
keywords: DNA damage; Keratinocytes; Lemon balm extract; Reactive oxygen species (ROS); Rosmarinic acid; UV radiation