Genotoxic changes in peripheral lymphocytes after therapeutic exposure to crude coal tar and ultraviolet radiation.
OBJECTIVE
Goeckerman therapy is based on combined exposure to UV radiation (UVA, UVB) and crude coal tar (PAHs). Some indicators suggest a genotoxic hazard, however, the level of genotoxic risk of the therapy has not yet been investigated sufficiently. This study aims to assesss the genotoxic risk.


METHODS
The studied group consisted of patients with chronic stable plaque psoriasis treated by Goeckerman therapy (n = 29). Heparin-treated peripheral blood samples were collected one day before the first treatment and immediately after the last procedure. The lymphocytes were isolated from the blood. The level of genotoxicity was evaluated using an alkaline version of the Comet assay which detects DNA single strand breaks (DNA-SSBs), a neutral version of the Comet assay which detects DNA double strand breaks (DNA-DSBs), and using chromosomal aberrations.


RESULTS
The level of DNA-SSBs increased insignificantly (median; Q1-Q3): 1.4 (0.4; 0.1-1.4) vs. 2.5 (0.6; 0.3-2.7) %tDNA (P = 0.11) and the level of DNA-DSBs increased significantly: 7.8 (6.5; 3.4-10.5) vs. 20.7 (19.3; 14.2-24.6) % DNA (P < 0.001). The total number of aberrated cells (P < 0.001) and structurally aberrated cells (P < 0.001) increased significantly.


CONCLUSIONS
The elevated levels of the DNA-DSBs and the chromosomal aberrations in the peripheral lymphocytes indicated a genotoxic hazard. However, the elevated level of the chromosomal abnormalities was below the upper level of the reference range for healthy Czech adults. While, the genotoxic risk appears to be low, Goeckerman treatment represents a further contribution to the lifetime load of genotoxic factors.
Department of Hygiene and Preventive Medicine, Faculty of Medicine in Hradec Kralove, Charles University in Prague, Hradec Kralove, Czech Republic.
Andrea
A
Malkova
Department of Medical Biochemistry, Faculty of Medicine in Hradec Kralove, Charles University in Prague, Hradec Kralove, Czech Republic.
Renata
R
Kohlerova
Department of Hygiene and Preventive Medicine, Faculty of Medicine in Hradec Kralove, Charles University in Prague, Hradec Kralove, Czech Republic.
Zdenek
Z
Fiala
Clinic of Dermal and Venereal Disease, University Hospital Hradec Kralove, Czech Republic.
Kvetoslava
K
Hamakova
Department of Medical Biophysic, Faculty of Medicine in Hradec Kralove, Charles University in Prague, Hradec Kralove, Czech Republic.
Iva
I
Selke-Krulichova
Department of Pathological Physiology, Faculty of Medicine in Hradec Kralove, Charles University in Prague, Hradec Kralove, Czech Republic Coresponding autor: Lenka Borska, e-mail.
Lenka
L
Borska
D000328:Adult; D000368:Aged; D002869:Chromosome Aberrations / Q000187:drug effects / Q000528:radiation effects; D002908:Chronic Disease; D003033:Coal Tar / Q000009:adverse effects*; D053903:DNA Breaks, Double-Stranded / Q000187:drug effects / Q000528:radiation effects; D005260:Female; D006801:Humans; D007641:Keratolytic Agents / Q000009:adverse effects*; D008214:Lymphocytes; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000628:therapy*; D014466:Ultraviolet Rays / Q000009:adverse effects; D014467:Ultraviolet Therapy / Q000009:adverse effects*
D007641:Keratolytic Agents; D003033:Coal Tar
chromosomal aberrations; comet assay; crude coal tar; genotoxicity; ultraviolet radiation