Goeckerman therapy (GT) of psoriasis vulgaris is based on the application of crude coal tar and ultraviolet radiation. We investigated DNA damage by the number of micronucleated binucleated cells (MNBC) in lymphocytes, serum homocysteine, vitamin B12, folic acid, and two polymorphisms (C677T and A1298C) in the MTHFR gene in 35 patients with exacerbated psoriasis vulgaris classified according to the psoriasis area and severity index (PASI) score and treated by GT. The median of PASI score decreased from nineteen to five, and MNBC increased from 10 to 18‰ after GT (p < 0.001 in both cases). Correlations of MNBC with homocysteine (Spearman's rho = 0.420, p = 0.012) and vitamin B12 (rho = -0.389, p = 0.021) before the therapy were observed. Hyperhomocysteinemia was an independent predictor of genotoxicity (OR 9.91; 95% CI, 2.09-55.67; p = 0.003). Homocysteine was higher in females than in males (13 vs. 12 µmol/L, p = 0.045). In contrast, vitamin B12 levels in the females were lower than in the males (160 vs. 192 pmol/L, p = 0.047). Vitamin B12 in the females were negatively influenced by smoking status (160 pmol/L in smokers vs. 192 pmol/L in non-smokers, p = 0.025). A significantly higher MNBC was found in CC homozygous patients (A1298C polymorphism) than in AC heterozygotes (32 vs. 16‰, p = 0.005) and AA homozygotes (32 vs. 18‰, p = 0.036). Our data showed that homocysteine participates in the pathogenesis of psoriasis. Its serum levels correlated with MNBC and allowed the prediction of DNA damage to appear within GT. Both micronutrients status and homocysteine metabolic pathway contribute to the genotoxicity of GT.

• Keywords
• Goeckerman therapy, folic acid, genotoxicity, homocysteine, psoriasis, vitamin B12,
• MeSH
• Coal Tar therapeutic use   MeSH
• Adult MeSH
• Homocysteine blood   MeSH
• Polymorphism, Single Nucleotide * MeSH
• Keratolytic Agents therapeutic use   MeSH
• Folic Acid blood   MeSH
• Middle Aged MeSH
• Humans MeSH
• Methylenetetrahydrofolate Reductase (NADPH2) genetics   MeSH
• Micronucleus Tests MeSH
• Micronutrients blood   MeSH
• DNA Damage drug effects   radiation effects   MeSH
• Psoriasis blood   genetics   pathology   therapy   MeSH
• Ultraviolet Therapy methods   MeSH
• Vitamin B 12 blood   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Coal Tar MeSH
• Homocysteine MeSH
• Keratolytic Agents MeSH
• Folic Acid MeSH
• Methylenetetrahydrofolate Reductase (NADPH2) MeSH
• Micronutrients MeSH
• MTHFR protein, human MeSH Browser
• Vitamin B 12 MeSH