Assessment of the Serum Paraoxonase1 Level and Its Relation to Total Oxidant Status and Disease Activity in Vitiligo Patients

Abstract Background Vitiligo is characterized by white macules and patches, whose size increases over time, due to the loss of melanocytes.It can appear at any time, and it significantly impairs the patients’ quality-of-life. Vitiligo is a multifactorial disorder due to genetic and environmental factors. One of the important hypotheses in the pathogenesis of vitiligo is the oxidative stress hypothesis, which is based on the reality of the formation of some toxic metabolites throughout pigment biosynthesis. Human paraoxonase-1 (PON1) is a Ca2+ dependent esterase synthesized in the liver. Reduced serum PON1 activity has been reported to be associated with some diseases under oxidative stress and inflammation conditions. Aim of the Work The aim of the work was to evaluate the serum level of paraoxonase1 in patients with vitiligo and its relation to total oxidant status and disease activity in vitiligous patients. Patients and Methods This is a case control study which included 48 vitiligo patients and 48 ageand sex-matched controls. The patients recruited from the Outpatient Dermatology Clinic at Ain Shams University Hospitals during the period from August 2020 till March 2021. Serum level of paraoxonase1 (PON1) and total oxidant status (TOS) where assessed by ELISA technique. Results We observed a statistically significant higher oxidative stress reflected by the high serum TOS levels among the vitiligo compared to controls. This finding supports the aforementioned hypothesis and it also came in accordance with the observations of high oxidative stress state in vitiligo patients which was repeatedly reported in many studies. Furthermore, we also reported the significant inverse relation between PON1 levels and the oxidative stress reflected by the serum TOS levels in vitiligo patients. This reflected the reduced protective antioxidant mechanisms in vitiligo patient making them more vulnerable to oxidative stress Conclusion Oxidative stress may play an important role in the pathogenesis of vitiligo. The finding of a PON1 decrease in vitiligo patients emphasises the underlying hypothesis in the progression of the disease, and it can highlight the effect of free radicals and leading oxidative damage in vitiligo disease. However, further, larger studies are necessary to confirm our results.