EFFECT OF HIDROALCOHOLIC EXTRACT OF Tamarindus indica L. ON REACTIVE OXYGEN SPECIES PRODUCTION BY HUMAN STIMULATED NEUTROPHILS

PAULA F. S.(1), AZZOLINI A. E.(2), LUCISANO-VALIM Y. M.(2)

(1)Department of Basic and Applied Immunology, FMRP; (2)Department of Physics and Chemistry, FCFRP, USP, Ribeirão Preto, SP, Brazil.

The neutrophil (PMNL) has the ability to release toxic products such as proteolytic enzymes and reactive oxygen species (ROS) capable of killing invading pathogens. Despite of the benefits of the ROS, they also produce deleterious effect to the organism in different types of illnesses like rheumatoid arthrits. The role of PMNL in ROS production in the physiopathology of various inflamatory diseases has drawn interest on the discovery of new compounds to modulate this process. In the present study the activity of hidroalcoholic extract of T. indica was assessed on luminol- and lucigenin- enhanced chemiluminescence (CL) produced by human neutrophils stimulated with particles of serum- opsonized zymosan (OZ). The total production of ROS by PMNL was measured by the luminol- enhanced CL (Lum CL) assay and the production of the superoxide anion (O2·-) by the lucigenin- enhanced CL (Luc CL) assay. Zymosan-induced ROS production was significantly inhibited by tamarind extract and had concentration-dependent inhibitory effects on luminol- and lucigenin-dependent CL (their IC50 values were 248.5 ± 16.62g/mL and 296.5 ± 35.55g/mL, respectively). The extract did not demonstrate toxicity to the neutrophils at the studied concentrations, in both used assays: activity of lactate dehydrogenase (LDH) and Trypan Blue dye exclusion test. Our results showed that the hidroalcoholic crude extract of T. indica has a strong inhibitory activity on neutrophils oxidative metabolism. Moreover, research is under way to characterize the main compounds of the extract related with the studied biological activity.

KEY WORDS: neutrophil, Tamarindus indica L., reactive oxygen species

FINANCIAL SUPPORT: CNPq

CORRESPONDENCE TO:

Fabiana da Silva Paula, Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, USP, Av. Café, s/n, CEP 14040-903, Ribeirão Preto, SP. Email: fabiana@rpm.fmrp.usp.br