Activation and apoptosis of mouse peritoneal macrophages by extracts of Larrea divaricata Cav. (jarilla)

ROBERTO DAVICINO; AIDA MATTAR; YOLANDA CASALI; CARINA PORPORATTO; SILVIA CORREA; BLAS MICALIZZI

INTERNATIONAL IMMUNOPHARMACOLOGY

Elsevier

Lugar: USA; Año: 2006 vol. 6 p. 2047 - 2056

1567-5769

Two aqueous extracts, decoction and infusion from Larrea divaricata Cav. (Zygophyllaceae) were investigated for immunomodulating activity on peritoneal macrophages (Mf ). Both extracts reduced significantly the cell viability assessed with the MTT assay at 1 and 4 mg/ml (decoction) and 0.8–4 mg/ml (infusion). Apoptotic morphology showed that at 1 and 4 mg/ml both infusion and decoction triggered an increment of the apoptosis. Pretreatment of Mf with decoction increased significantly the phagocytosis of zymosan and Candida albicans. The production of NO was estimated as nitrite using the Griess reagent. A slight but significant increase in NO release was observed after the incubation of both extracts (0.2 mg/ml) with LPS during 48 h. As shown in western blot data Mf cultured with infusion and LPS exhibited the stronger expression of iNOS compared with untreated cells. Both extracts (0.2 mg/ml) increased the binding of LPS-FITC to cells compared with untreated ones. The addition of Staphylococcus aureus blocked completely the binding of LPS-FITC to cells. L. divaricata stimulated the Mf activation at 0.2 mg/ml whereas it showed a clear pro-apoptotic activity at higher concentrations. The dual effects of L. divaricata are relevant considering the use of this plant to activate the immune system.