Association between serum paraoxonase 1 activity and its polymorphisms with multiple sclerosis: a systematic review

Background Human serum paraoxonase (PON) is an enzyme that is synthesized by the liver and enters the bloodstream, and it is transmitted by high-density lipoproteins (HDL). Paraoxonase 1 (PON1) is a hydrolytic enzyme with a wide range of substrates and the ability to protect against lipid oxidation. In this study, due to the activity of PON1 in the brain and its antioxidant effects on the reduction of neurological disorders in the central nervous system, the role of PON1 and its polymorphisms related to multiple sclerosis has been examined to enhance treatment methods. Methods This article is a systematic review. In this study, the role of PON1 and its polymorphisms in multiple sclerosis (MS) has been investigated. Articles published in Persian and international databases of SID, Google Scholar, ISI (WoS), Magiran, PubMed, Scopus, IranDoc, Science Direct, and Iran Medix were examined, using the search keywords of Paraoxonase 1, polymorphism, multiple sclerosis, and PON1. Results PON1 is undoubtedly a potential factor in the pathogenesis of multiple sclerosis, and it plays an important role in protecting antioxidants in the blood. Oxidative stress and lipid peroxidation are factors in the pathogenesis of MS. Both inflammatory cytokines and oxidative stress have a detrimental effect on PON1. However, reducing the activity of PON1 may help to restore the pathogenesis of the disease. Conclusion Decreased PON1 activity and PON1 polymorphism are associated with several neurological diseases, including ischemic stroke, white matter lesions (WMLs), amyotrophic lateral sclerosis (ALS), dementia, and Parkinson's disease. PON1-55M alleles in Italians and PON1-192Q alleles in Poles were associated with a high risk of MS. Moreover, PON1-55 and PON1-192 polymorphisms were not associated with MS onset age, nor its evolutionary type.