PPARγ gene expression analysis in psoriasis treatment

Introduction. PPARγ is the most studied PPAR subtype and is expressed predominantly in adipose tissue, heart, colon, kidney, spleen, intestine, skeletal muscle, liver, macrophages, and skin. In the skin, PPARγ controls the genetic regulation of gene network expression involved in cell proliferation, differentiation, and inflammatory responses. PPARγ (Peroxisome proliferator-activated receptor gamma) has only recently come to be considered a key player in the development and pathogenesis of psoriasis and psoriatic inflammatory conditions.
Aim of the study. To study PPARγ gene expression in the affected skin of psoriasis patients in comparison with visually unaffected skin. To study changes in PPARγ gene expression level in psoriasis affected skin in comparison with unaffected skin in patients before and after treatment with low-level laser radiation with a wavelength of 1.27 μm.
Materials and methods. Twelve patients with psoriasis participated in the study. Biopsies from unaffected skin areas were taken at a distance of about 3 cm from the affected skin. Analysis was performed by real-time PCR.
Results and Discussion. We quantitatively measured PPARγ gene expression using RT-PCR in the affected skin of patients with psoriasis in comparison with visually unaffected skin in the same patients before and after treatment with low-level laser radiation with a wavelength of 1.27 μm (the short-wave part of the infrared range). The study experimentally showed a 1.3 ± 0.27-fold decrease in PPARγ gene expression in the affected skin of psoriasis patients on average. Significant increase in over-expression of PPARγ gene up to 2,13 ± 0,47 times was observed after treatment of patients with low-level laser radiation.
Conclusions. PPARγ gene expression may be an indicator of the efficacy of psoriasis treatment at the molecular level, as well as become a new therapeutic target.

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