Metabolites identified in an extract of Baccharis articulata induce cytotoxic effects on human pbmcs

CARIDDI, LN; SABINI C; ESCOBAR F; REINOSO E; COMINI LR ; SABINI L

Mendoza

Encuentro; XLVIII REUNION ANUAL DE LA SOCIEDAD ARGENTINA DE INVESTIGACIONES EN BIOQUIMICA Y BIOLOGIA MOLECULAR; 2012

SOCIEDAD ARGENTINA DE INVESTIGACIONES EN BIOQUIMICA Y BIOLOGIA MOLECULAR

Baccharis articulata (Lam.) Pers. is used in the treatment of different disorders.We have demonstrated that cold aqueous extract of B. articulata (Ba-CAE) induced apoptosis in human peripheral blood mononuclear cells (PBMCs). The phytochemical study of the extract showed the presence of luteolin, acacetin and chlorogenic acid. The aim of this study was determine whether these compounds are responsible for the cytotoxic and apoptotic effects exhibited by the extract. The HPLC analysis shows the presence of luteolin (L) (1.96 ± 0.27%), acacetin (A) (1.12 ± 0.14%) and chlorogenic acid (ChA) (0.29 ± 0.05%). Analysis of PBMCs viability of each compound alone determined by staining of Trypan blue dye exclusion method revealed that ChA was the most toxic compound (CC50=18ìg/mL), followed by A (CC50=89ìg/mL) and L CC50=144ìg/mL). Both, ChA (4ìg/mL) and the combination of three compounds (L:25ìg/mL+A:14ìg/mL+ChA:4ìg/mL), in concentrations that these are present in Ba-CAE at 1280ìg/mL, showed 50.0±0.88% and 48.50±1.92% of decrease in PBMCs viability, respectively, and induced the cell death by apoptosis determined by Hoechst 33258 staining, TUNEL, and DNA fragmentation analysis. ChA not affect the Bax/Bcl-2 ratio, but neither activated the death receptor DR4. We suggested that toxic effects and death by apoptosis triggered by Ba-CAE on human PBMCswould be mainly produced by ChA.