PON1 activity and genotype in patients with arterial ischemic stroke and in healthy individuals.

OBJECTIVE: Paraoxonase-1 (PON1) is an esterase with antioxidant properties. Low PON1 enzyme activity or specific allelic polymorphisms seem to be associated with the risk of developing coronary artery disease or acute ischemic stroke (AIS). Our objective was to determine the distribution of both PON1 enzyme activity and its genotype in a group of patients with AIS.

MATERIALS AND METHODS: PON1 activity and the relative Q192R and L55M polymorphisms in the PON1 gene were assessed on 126 survivors of a first AIS and in 92 healthy subjects.

RESULTS: The genotype distribution for PON1 Q192R and L55M polymorphisms was similar in AIS patients and healthy subjects, but patients carrying the QRLL or RRLL genotype combination had lower PON1 enzyme activity compared with healthy subjects with the same genotype.

CONCLUSION: We postulate that lower than expected PON1 enzyme activity within specific genotypes might explain the reported association between R and L alleles and the risk of developing AIS.