Increased serum diamine oxidase activity in nonallergic patients with migraine

Background/objectives: Histamine has shown a possible role in the etiopathogenesis of migraine. It has been reported an association between some polymorphisms in the diamine oxidase (DAO) gene and migraine, especially in women. Two studies addressing DAO activity in migraine patients showed conflicting results. We investigated the possible relationship of serum DAO activity and histamine levels and 3 polymorphisms in the DAO gene with the risk for migraine. Methods: We studied the frequencies of DAO rs10156191, rs1049742 and rs1049793 genotypes and allelic variants in 298 migraine patients and 360 healthy controls (using a TaxiMan-based qPCR assay), and serum DAO activity and histamine levels in a subset of 99 migraine patients and 115 controls with strict exclusion criteria, and analysed the relationship of these variables with several clinical features of migraine. Results: The frequencies of the DAO genotypes and allelic variants analysed were similar in migraine patients and controls. Serum DAO activity was significantly higher in migraine patients (Vmax/Km 4.24 +/- 2.93 vs. 3.60 +/- 7.64, p < 0.001), especially in females (Vmax/Km 4.63 +/- 2.96 vs. 3.18 +/- 2.32, p < 0.0001), while serum histamine was similar in both study groups. Conclusion: Serum DAO activity was increased in patients with migraine, especially in females, while serum histamine levels were normal. None of the studied polymorphisms was associated with the risk for migraine.

Automated summary

This study investigated the relationship between serum diamine oxidase (DAO) activity and histamine levels, as well as three polymorphisms in the DAO gene, and the risk for migraine. The results showed that serum DAO activity was significantly higher in migraine patients, especially in females, while serum histamine levels were similar in both study groups. None of the studied polymorphisms were associated with the risk for migraine.