Comparison of serum paraoxonase 1 (pon1) activities among different sheep breeds in Turkey

Abstract

Paraoxonase 1 (PON1, EC 3.1.8.1) is a calcium dependent mammalian enzyme that is synthesized primarily in the liver and is secreted into the serum where it is associated with High Density Lipoproteins (HDLs) and has a protective effect against oxidation of Low Density Lipoproteins (HDLs). Beside antioxidant and antiatherogenic properties, PON1 is also a detoxigfier that can hydrolyze toxic organophosphates. Several studies have shown that PON1 can bind reversibly to organophosphate substrates which it hydrolyzes. Therefore, PON1 is the main means of protection of the nervous system against the neurotoxicity of organophosphates entering the circulation. This study was conducted to characterization of serum Paraoxonase 1 (PON1) activity from different sheep breeds namely Karacabey Merino, Kivircik, Tahirova, Akkaraman and Daglic. K-M and V-max values of five different sheep breed were determined by Lineweaver-Burk method. The values of V-max/K-M showed that Kivircik breed has teh greatest PON1 activity, on the other hand, Karacabey Merino breed showed the least activity toward paraox substrate.