Oxidative stress markers (MDA,SOD&GSH) and Proinflammatory Cytokine (interleukine-18)in Iraqi patients with Psoriasis vulgaris

Abstract

ackground: Psoriasis is a common chronic inflammatory skin disease with an unknown etiology. Psoriasis has been characterized by hyperproliferation accompanied by acanthosis andaberrant differentiation of keratinocytes. Several factors and cytokines, are assumed to be important. Recent studies indicate that various cytokines including tumor necrosis factor – α ,Interleukine-2R and Interleukine- 6 play an essential role in the induction and maintenance of psoriatic lesion.Objectives: To evaluate oxidative stress markers (Malondialdehyde (MDA),Super oxide dismutase( SOD) & Glutathion (GSH)) and proinflammatory mediators Interleukine-18 (IL-18) in the sera of patients with active psoriasis (Psoriasis vulgaris ) of mild-to-moderate and severe psoriasis compared to healthy controls,and to study correlation of the above markers with severity of psoriasis.Subjects & Methods: one hundred and teen (110) psoriasis patients were recruited from the dermatology Outpatient clinicin Murjan Hospital in (Babylon city)during the period from November 2011 to March 2013.Fasting serum samples were obtained on enrolment. All the patientsdid not receive any treatment (locally or systemically), for at least 20 days before enrolment. Age& sex matched with fifty five(55) healthy controls were also recruited. Serum IL-18 level were estimated using an Enzyme-Linked Immunosorbant Assay ( ELISA ) technique. The patients group were subdivided to three groups according to the disease severity, into mild psoriasis group , moderate psoriasis group and severe psoriasis group. Serum MDA levels were assessed using thiobarbituric acid (TBA) method of Buege and Aust SOD and GSH was measured by Burtis and Ashwood, SOD levels using modified photochemical Nitroblue Tetrazolium (NBT) method utilizing sodium cyanide as peroxidase inhibitor.Results & Discussion: Serum IL-18 shows statistically significant elevation in patients group compared to healthy controls( p< 0.05 ). Levels of MDA were significantly increased (p<0.001) where as the GSH and SOD were significantly decreased (p<0.001) in patients with psoriasis compared to healthy control.Also they were all statistically significant increased in serum levels of IL-18 and MDA while a significant decreased in serum levels of SOD and GSH in patients with severe psoriasis compared to these with mild-to moderate psoriasis ( p <0.05 ).Conclusions: These data support the view that serum IL-18 , MDA, SOD and GSH areinvolved in the pathogenesis of psoriasis, possibly by induction and maintenance of psoriatic lesion. Its recommend a use of cytokine (IL-18) as a useful follow-up marker for monitoring of psoriatic patients and optimizing therapeutic strategies.Keywords: Psoriasis vulgaris, Cytokines, IL-18 and oxidative stress.