RESUMO
To investigate the apoptosis-induction effect of brucine on human chronic myeloid leukemia cell line K562 cells, K562 cells were exposed to various dosages of brucine. MTT method was used to assayed the growth inhibition effect of brucine on K562 cells. The apoptosis of K562 cells was detected by acridine orange/ethidium bromide (AO/EB) double staining, Annexin-V/PI double labeling method and DNA agarose gel electrophoresis. The results showed that brucine could remarkably inhibit the K562 cell growth in a concentration-dependent and time-dependent manners at the range of 50 to 400 µg/ml, and its most significant inhibition was observed at 400 µg/ml for 72 hours and the inhibition rate was 94.0%. Staining of cells with AO-EB revealed that brucine induced nuclear chromatin condensation. After the K562 cells were treated with the brucine of 400 µg/ml for 72 hours, the most of the nucleus were orange stained and condensation-like or bead-like showing apoptotic morphology. The K562 cells treated with brucine of different concentrations (50, 100, 200, 400, 800 µg/ml) for 72 hours, Annexin-V/PI detection showed brucine could induce apoptosis of K562 cells, and apoptosis rate increased gradually with increasing concentration of drugs. The K562 cells treated with brucine of 400 µg/ml for 72 hours displayed typical ladder strap in DNA gel electrophoresis. It is concluded that brucine can efficiently inhibit cell growth and induce apoptosis of K562 cells with dose-dependent manner in concentrations of 50 - 400 µg/ml.
Assuntos
Humanos , Apoptose , Proliferação de Células , Células K562 , Estricnina , FarmacologiaRESUMO
The aim of this study was to investigate the effect of brucine on secretion of TNF-α, IFN-γ, IL-4 and proliferation of T lymphocytes in patients with aplastic anemia (AA), and to explore its mechanism. Peripheral blood T lymphocytes from 10 patients with AA and 10 healthy volunteers were isolated, purified and cultured. T lymphocytes from the patients were divided into 0, 100, 200 and 400 µg/ml brucine-treated groups. T lymphocytes from healthy volunteers were used as control group. After being cultured for 72 hours, the levels of TNF-α, IFN-γ, IL-4 in the supernatant of cultured T lymphocytes from AA patients were detected by ELISA, and the proliferation of T lymphocytes from AA patients was detected by MTT. The results showed that compared with the normal control group, the levels of TNF-α and IFN-γ in the culture supernatant significantly increased, and IL-4 was significantly decreased. The levels of TNF-α and IFN-γ in the culture supernatant of brucine treated groups were lower, and were dependent on the concentration of brucine. However, the levels of IL-4 were found to be not obviously changed. The inhibition rate of T lymphocytes in 100, 200 and 400µg/ml brucine-treated groups were (13.61 ± 4.31)%, (14.28 ± 4.31)% and (15.12 ± 4.56)% respectively, among which the differences were not statistically significant. It is concluded that the brucine can reduce the levels of TNF-α and IFN-γ through inhibiting the proliferation of T lymphocytes in AA patients, which provides experimental basis for therapy of AA patients.