Peroxisome proliferator receptor (PPAR) β/δ in psoriatic patients before and after two conventional therapeutic modalities: methotrexate and PUVA.

Peroxisome proliferator-activated receptor β/δ is a member of the nuclear hormone receptor superfamily suggested to contribute to psoriasis pathogenesis. Methotrexate and PUVA mainly target the T cell-mediated immunopathology of psoriasis. Our work aimed at estimating PPARβ/δ in psoriatic patients and investigating whether the standard therapeutic modalities (methotrexate and PUVA) exert their anti-psoriatic activity partially through altering PPARβ/δ levels. RT-PCR was used to measure PPAR β/δ mRNA levels in twenty four chronic plaque psoriasis patients. Patients were divided into two groups (12 patients each); group A received intramuscular methotrexate and group B was treated by PUVA 3 times/week in a PUVA 1000 cabin for ten weeks each, followed by measurement of PPAR β/δ mRNA levels. Twelve healthy volunteers served as controls. PPAR β/δ mRNA levels were significantly elevated in all patients and significantly decreased ten weeks after treatment, however, post treatment levels were still significantly elevated in comparison with those of controls. PPAR β/δ mRNA levels showed a significant positive correlation with disease duration.