Passion fruit (Passiflora edulis) leaf extract modulates the oxidative metabolism of rat peritoneal neutrophils in a model of inflammation

This study was conducted to evaluate the effect of extracts of Passiflora edulis Sims leaves on the oxidative metabolism of rat peritoneal neutrophils using a model of acute inflammation. The extract was obtained by maceration in 70% ethanol, evaporation under reduced pressure and lyophilisation. Total phenolic content (TP) was determined by the Folin-Ciocalteu assay. The P. edulis extract, in different doses, was administered by gavage 1 h prior to inflammation induction by carrageenan (8 mg/kg, i.p.); five hours later, the neutrophils were obtained by intraperitoneal lavage. The tests performed in neutrophils were cytochrome C and chemiluminescence assay as well as myeloperoxidase (MPO), superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) activities. The administration of the extract reduced the number of neutrophils recruited to the site of inflammation; however, the extract did not alter the activity of NADPH oxidase as well as SOD activity in these cells. The MPO and CAT activities in peritoneal neutrophils of rat treated with extract was lower than in the control group, and the GPx activity was increased. Based on the experimental model utilised, the anti-inflammatory potential of P. edulis leaf extract could be related to the presence of phenolic compounds in the extract.