Aims: Our study investigated reactive oxygen species (ROS) generation and angiotensin II type 1 receptor (AT(1)-R) expression in primed polymorphonuclear leukocytes (PMNs) of dyslipidaemic subjects over prolonged statin treatment.
Methods and results: Sixteen untreated dyslipidaemic subjects with moderately increased cardiovascular risk (National Cholesterol Education Program, Adult Treatment Panel III) were studied before and during long-term (1 year) simvastatin treatment. Neutrophils from dyslipidaemic subjects generated more ROS in comparison with cells from healthy control subjects. After 1 year of simvastatin treatment, ROS production (delta N-formyl-Met-Leu-Phe-induced generation and area under the curve) was significantly reduced. At baseline, AT1-R mRNA expression was also higher in dyslipidaemic subjects than in healthy controls and it was reduced after clinical treatment with simvastatin. In a subgroup of patients, a reduced angiotensin II-induced ROS generation was also observed upon clinical simvastatin treatment. Moreover, a direct effect of statin on the upregulated AT(1)-R expression was demonstrated in vitro in neutrophils of untreated dyslipidaemic subjects.
Conclusion: A consistent reversion of pro-inflammatory oxidative functional response and reduction of AT(1)-R expression in primed PMNs was observed in patients during long-term statin treatment. The AT1-R reduction over treatment may contribute to the normalization of dysregulated neutrophil activation which occurs in the pre-clinical phase of atherosclerosis.