ABSTRACT
Objective To determine the relationship of cytochrome P-450 epoxygenase metabolites of arachidonic acids with impaired endothelium-dependent vasorelaxation in the healthy elderly. Methods A case-control study was employed.The study enrolled 60 healthy young adults (group A) and 60 healthy senior citizens (group B) of Han population in Shanghai. Serum contents of 14,15-dihydroxyeicosatrienoic acid (14,15-DHET) (a stable metabolite of 14,15-EET), 6-Kote-PGF1a (a stable metabolite of prostaglandin) and TXB2 (a stable metabolite of thromboxane A2) were measured using ELISA kits. The endothelium-dependent vasorelaxation (EDV) and endothelium-independent vasorelaxation (NEDV) in brachial arteries were determined by color Doppler ultrasound. Results Compared with group A, group B had significant higher levels of hemoglobin A1c, triglyceride and cholesterol levels (P＜0.01), and significant lower levels of 14,15-DHET and 6-Kote-PGF1a (P＜0.001), leading to increased values of TXB2/6-Kote-PGF1a and TXB2/14,15-DHET. There was bigger basal interior diameter of brachial arterials with reduced EDV and NEDV response (P＜0.01 and P＜0.05, vs. group A respectively) in group B. Moreover, the age was negatively correlated with 14,15-DHET and TXB2/14,15-DHET. Conclusions Our results indicate that the impaired EDV and NEDV in aging are associated with reduced production of arachidonic acid metabolites through cytochrome P-450 epoxygenase pathway and cyooxygenase pathway of endothelium in the healthy elderly.