Cytotoxicity of isolated compounds from Picrasma crenata (Vell.) Engl. in animal tumor cell (HTC).

The study aim was to evaluate the cytotoxic activity, using the MTT test [3-(4,5-Dimethilthiazol-2-yl)-2,5-diphenil tetrazolium bromide], from the crude extract of Picrasma crenata (Pau Tenente) and its isolated compounds, quassin and parain, in culture of rat liver tumor cells (HTC). The test was carried out exposing the cells for 24, 48 and 72 hours to concentrations of 5, 10, 50, 100, 200, 300, 400, 500 and 1000 µg of crude extract of Pau Tenente/mL of culture medium and 1, 5, 10, 15, 20, 40, 60, 80 and 100 µg of quassin or parain compounds/mL of culture medium. The absorbances averages results obtained showed that the crude extract did not present cytotoxicity for the HTC cells in all the concentrations and evaluated times. For quassin, the concentrations of 80 and 100 µg/mL were cytotoxic, after 72 hours of treatment. For parain, the concentrations of 1, 5, 20, 40, 60, 80 and 100 µg/mL, in 72 hours, were cytotoxic, revealing a new activity for this compound. Thus, the results demonstrate a first indication of the cytotoxic activity of compounds quassin and parain, adding an important social and economic value to them, and may have application in future research and in pharmaceutical industry.

Cytotoxicity of extracts and compounds isolated from Croton echioides in animal tumor cell (HTC).

The search for compounds with anticancer effects is of paramount importance today due to the high incidence of the disease. The Euphorbiaceae family is known for having compounds with therapeutic properties, one of its genera being Croton. It has several species, which contain compounds already known for their biological activities, presenting anti-inflammatory, antimicrobial and anticancer properties. Thus, the cytotoxicity/antiproliferative activity of semi-purified fractions and compounds isolated from Croton echioides in liver tumor cells of Rattus norvegicus (HTC) was evaluated by the MTT test. The semi-purified fractions showed cytotoxicity at concentrations above 200 µg/mL, at 24, 48 and 72 hours, reaching cell viability of 24.78% [400 µg/mL] at 24 hours, 12.79% [500 µg/mL] at 48 hours and 10.57% [300 µg/mL] at 72 hours. For the isolated compounds, lupeol had a cytotoxic effect in all concentrations (1, 5, 10, 15, 20, 40, 60, 80 and 100 µg/mL) and tested times (24, 48 and 72 hours), reaching minimum viability of 4.37% [100 µg/mL], within 72 hours. The clerodan diterpenes CEH-1 and CEH-4 also showed antiproliferative activity, with minimum viability of 36.19% [100 µg/mL] over 72 hours and 21.33% [100 µg/mL] over 48 hours, respectively. However, the clerodan diterpenes CEH-2 and CEH-3 did not shows a cytotoxic effect for HTC cells. Thus, there is a cytotoxic/antiproliferative potential of C. echioides against tumor cells, with targeted to mitochondrial enzymes, associated with cell proliferation, indicating that this species deserves prominence in the search for new molecules for the treatment of cancer.