Cytogenotoxic effects of a characterized aqueous extract of Baccharis articulata (Lam.) Pers. (Asteraceae) on normal cells

CARIDDI LN; ESCOBAR FM; SABINI MC; TORRES C; RESER AL; COMINI L; SABINI LI

Simposio; XXII Simpósio de Plantas Medicinais do Brasil; 2012

Introduction: Cold aqueous extract of Baccharis articulata (Ba-CAE) induces the death of human peripheral blood mononuclear cells (PBMCs) and exerts mutagenic effects on mice at 6h post-injection (p.i). The aim was to investigate whether the PBMCs death is due to apoptosis, and whether this extract exerts mutagenic effects on mice at 24 and 48 h p.i. In addition, Ba-CAE was chemically characterized.Materials and methods: PBMCs were exposed to extract (10, 20, 40, 80, 160, 320, 640 and 1280 μg/mL) for 18-24 h. Cell viability was determined by trypan blue dye exclusion method. Apoptosis was determined by Hoechst 33258 staining, TUNEL, and DNA fragmentation analysis by agarose gel electrophoresis. BALB/c mice were injected with extract (1800, 900 and 450 mg/kg) and sacrificed at 24 and 48 h p.i. Bone marrow samples were used to assess chromosome mutations by the micronucleus test. The main metabolites in the Ba-CAE were identified and quantified by HPLC.Results: A dose-dependent toxicity of Ba-CAE was demonstrated on PBMCs (CC50=165g/mL). Hoechst staining showed several apoptotic figures. The percentage of TUNEL-positive per 400 cells was: control: 7+1%, cells treated: 10μg/mL(8+1%), 20μg/mL(9+3%), 40μg/mL(43+11%)*, 80μg/mL(58+18%)*, 160μg/mL(62+13%)*, 320μg/mL(68+20%)**, 640μg/mL(73+10%)**, 1280μg/mL(88+13%)**; *p