RESUMO
Background & objectives: Secretory phospholipase A2 (sPLA2) and oxidized low density lipoprotein (oxLDL) are considered as oxidative and inflammatory markers. The effects of oxLDL have been shown to be inhibited by paraoxonase (PON1). This study was undertaken to investigate the relationship between oxidative and inflammatory markers in hypertensive patients with or without antihypertensive drug treatment. Methods: Newly diagnosed hypertensive patients (n=35) and hypertensive patients who had been taking angiotensin converting enzyme (ACE) inhibitors as antihypertensive therapy (10 or 20 mg/day for 9 ± 2 wk; n=35) and age-matched normotensive subjects (controls; n=20) were included in this study. Plasma sPLA2, oxLDL and PON1 activities were determined. Results: Hypertensives had higher plasma oxLDL and sPLA2 levels (P<0.01) and lower PON1 levels than the controls (P<0.01). Treated hypertensives had lower plasma sPLA2 and oxLDL levels and higher PON1 activities than hypertensives (P<0.01). sPLA2 was positively correlated with oxLDL (r=0.433, P<0.01) and negatively correlated with plasma PON1 (r= - 0.540, P<0.01) in untreated hypertensives. In controls and treated hypertensives, plasma PON1 was positively correlated with oxLDL (r= 0.455, r=0.429, P<0.01, respectively) and sPLA2 (r= 0.450, r=0.506, P<0.01, respectively). Interpretation & conclusions: Reduction in PON1 activity and elevation in both sPLA2 activities and oxLDL levels might be involved in elevated oxidative stress and inflammation. ACE inhibitor treatment may help reduce inflammation and oxidative stress in hypertensives.