title: Influence of dermal exposure to ultraviolet radiation and coal tar (polycyclic aromatic hydrocarbons) on the skin aging process.
abstract: BACKGROUND
  Ultraviolet radiation (UVR) and crude coal tar (CCT) containing PAHs can accelerate the skin-aging process (SAP). However, UVR induces the formation of an important protective factor in SAP (vitamin D).
  
  
  OBJECTIVE
  To determine the relation of SAP to selected risks and benefits of combined dermal exposure to UVR and coal tar (PAHs).
  
  
  METHODS
  The study group consisted of patients with chronic stable plaque psoriasis and treated by Goeckerman therapy (GT; daily dermal application of UVR and 5% CCT ointment). The levels of urinary 1-hydroxypyrene (1-OHP), oxidative stress (DNA and RNA damage), genotoxic damage (chromosomal aberration in peripheral lymphocytes; ABC), 25-hydroxy-vitamin D [25(OH)D] and the PASI score were evaluated before and after GT.
  
  
  RESULTS
  Intensive dermal absorption of PAHs was confirmed by increased levels of 1-OHP (p<0.01). After the therapy, we found an increased level of oxidative stress (p<0.05), an increased level of genotoxic damage (ABC; p<0.001), a high efficiency of the treatment (p<0.001) and an elevated production of 25(OH)D (p<0.01). We also found a relationship between the duration of UVR and the genotoxic damage (p<0.01), vitD (p<0.05) and the PASI score (p<0.05). Furthermore, we found a relationship between oxidative stress and 25(OH)D (p<0.05) and between genotoxic damage and the PASI score (p<0.05).
  
  
  CONCLUSIONS
  Dermal exposure to UVR and coal tar (PAHs) enhances the level of oxidative stress and genotoxic damage and thus contributes to SAP. However, the exposure is very effective as a treatment and elevates the production of 25(OH)D, the protective factor in SAP. According to our results, UVR is probably a more hazardous factor in SAP.
authors.affiliation: Institute of Pathological Physiology, Charles University in Prague, Faculty of Medicine in Hradec Kralove, Šimkova 870, 50038 Hradec Kralove, Czech Republic. Electronic address: borka@lfhk.cuni.cz.
authors.forename: Lenka
authors.initials: L
authors.lastname: Borska
authors.affiliation: Institute of Clinical Immunology and Allergology, Charles University in Prague, Faculty of Medicine in Hradec Kralove, 50038 Hradec Kralove, Czech Republic.
authors.forename: Ctirad
authors.initials: C
authors.lastname: Andrys
authors.affiliation: Institute of Clinical Immunology and Allergology, Charles University in Prague, Faculty of Medicine in Hradec Kralove, 50038 Hradec Kralove, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Krejsek
authors.affiliation: Institute of Clinical Biochemistry and Diagnosis, Charles University in Prague, Faculty of Medicine in Hradec Kralove, 50038 Hradec Kralove, Czech Republic.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Palicka
authors.affiliation: Institute of Clinical Biochemistry and Diagnosis, Charles University in Prague, Faculty of Medicine in Hradec Kralove, 50038 Hradec Kralove, Czech Republic.
authors.forename: Viktor
authors.initials: V
authors.lastname: Vorisek
authors.affiliation: Clinic of Dermal and Venereal Diseases, University Hospital Hradec Kralove, 500 05 Hradec Kralove-Novy Hradec Kralove, Czech Republic.
authors.forename: Kvetoslava
authors.initials: K
authors.lastname: Hamakova
authors.affiliation: Institute of Pathological Physiology, Charles University in Prague, Faculty of Medicine in Hradec Kralove, Šimkova 870, 50038 Hradec Kralove, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Kremlacek
authors.affiliation: Institute of Pathological Physiology, Charles University in Prague, Faculty of Medicine in Hradec Kralove, Šimkova 870, 50038 Hradec Kralove, Czech Republic.
authors.forename: Pavel
authors.initials: P
authors.lastname: Borsky
authors.affiliation: Institute of Hygiene and Preventive Medicine, Charles University in Prague, Faculty of Medicine in Hradec Kralove, 50038 Hradec Kralove, Czech Republic.
authors.forename: Zdenek
authors.initials: Z
authors.lastname: Fiala
mesh_terms: D000279:Administration, Cutaneous; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood / Q000652:urine; D002908:Chronic Disease; D003033:Coal Tar / Q000008:administration & dosage* / Q000009:adverse effects; D003131:Combined Modality Therapy; D004249:DNA Damage; D005260:Female; D006801:Humans; D007641:Keratolytic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects / Q000528:radiation effects; D011084:Polycyclic Aromatic Hydrocarbons / Q000008:administration & dosage* / Q000009:adverse effects; D011565:Psoriasis / Q000175:diagnosis / Q000378:metabolism / Q000628:therapy*; D011721:Pyrenes / Q000652:urine; D020871:RNA Stability / Q000187:drug effects / Q000528:radiation effects; D015595:Skin Aging / Q000187:drug effects* / Q000528:radiation effects*; D012907:Smoking / Q000009:adverse effects; D013997:Time Factors; D016896:Treatment Outcome; D014467:Ultraviolet Therapy / Q000009:adverse effects / Q000379:methods*; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood; D014916:Whole-Body Irradiation; D055815:Young Adult
chemical_list: D015415:Biomarkers; D007641:Keratolytic Agents; D011084:Polycyclic Aromatic Hydrocarbons; D011721:Pyrenes; D014807:Vitamin D; D003033:Coal Tar; C104450:25-hydroxyvitamin D; C033146:1-hydroxypyrene
keywords: 25-Hydroxy vitamin D; Chromosomal aberration; Oxidative stress; Polycyclic aromatic hydrocarbons; UV radiation