Effects of static and electromagnetic fields on human serum paraoxonase-1 activity in vitro

Introduction: In recent years the relationship between electromagnetic fields and coronary artery disease is attracted a considerable attention. Low density lipoprotein (LDL) oxidation is the initial step in the development of atherosclerosis. Paraoxonase1 (PON1) protects LDL and High density lipoprotein (HDL) against oxidative processes, thus preventing the formation of atherogenic (oxidized-LDL) ox-LDL molecules. In this study we investigated the effects of static magnetic fields (SMFs) and extremely low frequency electromagnetic fields (ELF-EMFs) on PON1 activity as one of the independent risk factors for cardiovascular disease. Materials and methods: Pooled serum sample of 20 healthy men were exposed to SMFs and EMFs flux densities of 0.125, 0.25, 0.5, 1, 2, 3 and 4 mT for 60, 120 and 180 minutes at 25&deg;C and then PON1 activity was measured spectrophotometrically using paraoxon as substrate. Results: EMFs of 0.125-1 mT had no effect on PON1 activity. Exposure to magnetic flux density of 2 mT leads to a significant increase in PON1 activity in 1 hour (P <0.05). Magnetic flux density of 3 and 4 mT, after 1hour of exposure, lead to an increase of PON1 activity to 1.2% and 2.8%, respectively (P <0.01). Conclusion: PON1 activity is influenced by a variety of agents like environmental, pharmacological, and lifestyle factors as well as age and sex. According to the finding of this study ELF-EMFs can alternate the serum activity of PON1 in vitro. If this effect of EMFs on PON1 activity has proven in vivo, it can be considered as an effective factor in coronary artery disease.