Background: Cytochrome-P450 eicosanoids from arachidonic acid, including vasodilator epoxyeicosatrienoic acids (EETs) and the vasoconstrictor 20-HETE, are important in regulating blood pressure, vascular tone, and cardiac and renal function. This study examined plasma 20-HETE and EETs in relation to blood pressure and vascular stiffness in a cohort of 1054 community-dwelling young adults from the Raine Study at 27 years.
Methods: Plasma 20-HETE, EETs, and their hydroxylated products were measured by liquid chromatography-tandem mass spectrometry. Pulse wave velocity and aortic distensibility were measured to assess vascular stiffness. Sex differences were assessed using univariate analysis. Multiple regression models assessed the relationship between 20-HETE and systolic blood pressure (SBP) and measures of vascular stiffness.
Results: The regression model for SBP showed a positive relationship with plasma 20-HETE (β, 0.092; P<0.0001), after adjusting for sex (P<0.0001), body mass index (P<0.0001), (ln)triglycerides (P<0.0001), and (ln)Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) (P=0.015), and accounted for 29% of the variance in SBP. 20-HETE was positively related to pulse wave velocity (β, 0.059; P=0.021); after adjusting for sex (P<0.0001), SBP (P<0.0001), (ln)triglycerides (P=0.014), (ln)HOMA-IR (P=0.0001), (ln)high-sensitivity C-reactive protein (P=0.005), and age (P=0.002), the model accounted for 34% of the variance in pulse wave velocity. 20-HETE was inversely associated with aortic distensibility (β, -0.051; P=0.029), independent of sex (P<0.0001), SBP (P<0.0001), and (ln)HOMA-IR (P<0.0001); the model accounted for 25% of the variance in aortic distensibility. Plasma EETs were not significant predictors of SBP or vascular stiffness.
Conclusions: In young adults, 20-HETE may play a fundamental role in regulating blood pressure and vascular stiffness independent of numerous cardiometabolic risk factors and cytochrome 450-derived EETs.
Registration: URL: https://www.anzctr.org.au; Unique identifier: CTRN12617001599369.
Keywords: 20-hydroxy-5,8,11,14-eicosatetraenoic acid; blood pressure; cytochrome P-450 enzyme system; eicosanoids; pulse wave analysis.