ABSTRACT
TNF-alpha is known to play an important role in UV-induced immunomodulation and photodamage. It plays a role in UVB-mediated induction of apoptosis and is a strong inducer of the c-Jun N-terminal kinase (JNK) pathway, which eventually leads to the loss of dermal collagen and elastin content. Recently chimeric anti-TNF-alpha has been introduced as a therapy for rheumatoid arthritis. The aim of the present study was to investigate the effect of anti-TNF-alpha treatment on UV-induced DNA damage, apoptosis, and induction of matrix metallo proteinases. Twelve patients with rheumatoid arthritis were included and irradiated with 2 MED broadband UVB before and after administration of 0.5 mg/kg anti-TNF-alpha monoclonal antibody. Twenty-four hours after irradiation biopsies were taken. Frozen and paraffin sections were stained for p53, c-Jun, phosphorylated c-Jun, sunburn cells and MMP-1. No significant changes were observed in the expression of p53 and sunburn cells and MMP-1 content after treatment with anti-TNF-alpha, whereas a slight but significant decrease in c-Jun and phosphorylated c-Jun expression was noted (P = 0.0250 and P = 0.0431, respectively). Our results showed no influence of anti-TNF-alpha on UV response at therapeutic doses in patients with rheumatoid arthritis.
