Retracted : Role of resolvin D1 in psoriasis before and after narrowband ultraviolet B phototherapy: A case‐control study

Resolvin D1 (RvD1) is an endogenous lipid mediator that originated from docosahexaenoic acid that stimulates a bimodal mechanism in the anti-inflammatory activity in addition to regulation of the inflammatory reaction. The study aimed at assessing the tissue level of RvD1 in psoriasis to study its role in the etiopathogenesis of psoriasis, studying the action of NB-UVB on the level of resolvin D1 in psoriasis, and raising the possibility of using resolvin D1 as a new therapy for psoriasis in the future. This case-control study included 20 psoriasis patients and 20 healthy controls. Patients took narrowband ultraviolet B (NB-UVB) for 36 sessions. Skin biopsies were taken before and after treatment from patients and from controls to assess the expression of RvD1 by a quantitative real-time polymerase chain reaction. Our findings revealed a statistically significant difference (P < .001) between psoriasis patients (either before or after treatment) and controls with lower levels of RvD1 in psoriasis patients. On comparing the RvD1 levels in psoriasis patients before and after treatment, a statistically significant increase was detected after treatment (P < .001). Tissue RvD1 levels in psoriasis patients were lower than healthy controls and increased after NB-UVB treatment in psoriasis patients. Thus, it is suggested that RvD1 might have a role in the etiopathogenesis of psoriasis. Moreover, the significantly up-regulated tissue levels of RvD1 in patients after treatment with NB-UVB highlighted a novel mechanism of phototherapy-mediated response in psoriasis by up-regulating RvD1 level.