Phytochemical investigation, antinociceptive activity and cytotoxicity of crude extracts of Calea uniflora Less.
Résumé
Calea uniflora Less. is a medicinal plant used in the treatment of inflammation and haematomas in southern Brazil. The aim of this study was to investigate the antinociceptive effects and cytotoxicity of C. uniflora. Regarding phytochemical evaluation, the crude extracts of plant were analysed by high-performance liquid chromatography (HPLC). Antinociceptive activities utilised models on chemical and thermal stimuli in vivo. To evaluate cytotoxic activity, the 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide method (MTT test) was utilised in vitro. Phytochemical analyses verified the presence of flavonoids and sesquiterpenes. Regarding antinociceptive activity, the models produced significant results that correspond to chemical at doses of 100 and 300 mg/kg of the crude extract as compared to the control groups, respectively. The rota rod model showed satisfactory results, since the extract did not cause motor incoordination and sedation in this experiment. In the in vitro cytotoxic tests, the crude extracts and ethyl acetate and butanolic fractions produced IC50 values greater than 58 µg/mL with the HaCaT lineage and 48 µg/mL with the B16-F1 lineage; thus, these values did not produce cytotoxic effects. According to these results, flavonoids and alkaloids were found in C. uniflora extracts. Pharmacological activities were also detected as reported by the local population that uses this plant in traditional medicine, especially antinociceptive and cytotoxic activities. Key words: Antinociception, cytotoxicity, phytochemistry, Calea uniflora, medicinal plant.