Carotid Intima-Media Thickness for Atherosclerosis

Phospholipase A2 Receptor Gene Polymorphisms Alter its Functions and Present a Genetic Risk of an Increased Intima-Media Thickness of the Carotid Artery

Aims: Phospholipase A₂ receptor 1 (PLA₂R) has multiple biological functions other than functioning as a receptor for secretory PLA_2s. Two nonsynonymous polymorphisms in the C-type lectin-like domains (CTLD) 1 of PLA₂R gene have been associated with idiopathic membranous nephropathy. This study examined whether the same PLA₂R polymorphisms may alter functions of PLA₂R in cells expressing the variant PLA₂R. In addition, the clinical relevance of the experiment was examined.

Methods: Two nonsynonymous polymorphisms (T/C at rs3749117 and G/C at rs35771982) in CTLD1 of PLA₂R gene were completely linked. HEK293 cells expressing human wild-type PLA₂R (T at rs3749117 and G at rs35771982) or human mutant PLA₂R that had double mutations (C at rs3749117 and C at rs35771982) were constructed.

Results: HEK293 cells expressing mutant PLA₂R had lower migratory and proliferative responses to collagen I compared with cells expressing wild-type PLA₂R. In 580 male patients, PLA₂R gene polymorphisms were associated with an increase in maximum intima-media thickness (maxIMT) of the carotid artery. The multivariate regression model showed that PLA₂R gene polymorphisms were a risk factor of an increased maxIMT that was independent of conventional risk factors (OR = 1.93, 95% CI: 1.17–3.19, p < 0.01).

Conclusions: The nonsynonymous common variants of PLA₂R gene altered biological functions in cells expressing variant PLA₂R. PLA₂R gene polymorphisms present a genetic risk of an increased IMT of the carotid artery in male. The functional changes in the variant PLA₂R may potentially be responsible for its association with an increased IMT of the carotid artery.