ABSTRACT
This study was aimed to investigate the inducing-apoptosis effect of brucine on human monocytic leukemia cell line THP-1 cells and its possible mechanism. The inhibition effect of brucine on growth of THP-1 cells was measured by CCK-8 method. Morphological changes of THP-1 cells treated with brucine was detected by acridine orange/ethidium bromide (AO/EB)double staining. Annexin-V/PI double labeling method was used to assay the apoptosis rate of THP-1 cells. The effect of brucine on THP-1 cell cycle distribution was detected by PI single staining. RT-PCR was used to detect the expression of BCL-2 and BAX. The results showed that the brucine could inhibit the THP-1 cell growth in concentration and time-dependent manners at the range of 50 to 400 µg/ml. The cells stained with AO/EB revealed that the brucine induced the nuclear chromatin condensation. After the THP-1 cells were treated with brucine of 400µg/ml for 48 hours, most nucleic were stained as orange-red, and condensed, displaying the late apoptotic cell morphology. Annexin-V/PI detection showed that brucine could induce apoptosis of THP-1 cells in a concentration-dependent manner. Compared with the control group, more cells in brucine-treated group were arrested at G0/G1 phase in a concentration-dependent manner. RT-PCR detection revealed that the expression of BCL-2 was down-regulated strikingly and BAX was up-regulated. It is concluded that brucine can efficiently inhibit cell growth and block THP-1 cells in G0/G1 phase. The mechanism of THP-1 cell apoptosis induced by brucine may be related to the inhibition of BCL-2 and activation of BAX.
Subject(s)
Humans , Apoptosis , Cell Cycle , Cell Line, Tumor , Cell Proliferation , Proto-Oncogene Proteins c-bcl-2 , Metabolism , Strychnine , Pharmacology , bcl-2-Associated X Protein , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To establish a hepatitis C virus (HCV) diagnostic assay using a protein array based on the quantum dots (QDs) encoded microbeads.</p><p><b>METHOD</b>Using QDs encoded microbeads array and immunofluorescence techniques, the highly purified HCV NS3, NS4, NS5 and Core protein were respectively immobilized on the surface of encoded beads, which were used for the detection of anti-HCV antibody in serum. To evaluate the microbeads protein array, 120 HCV positive and 50 HCV negative samples were tested, and compared with recombinant immunoblot assay(RIBA) results as golden standard. The sensitivity, specificity and accuracy value were calculated.</p><p><b>RESULTS</b>Compared 120 positive samples detected with RIBA, the sensitivity of microbeads array is 97.50% (117/120), the specificity is 96.0% (48/50), and accuracy is 97. 06% [(117 + 48)/(120 + 50)], The sensitivity of microbeads protein array is similar with RIBA methods. In the 120 positive samples tested with protein array, the positive rate of anti-HCV Core is 92. 50% (111/120) , the positive rate of anti-HCV NS3 is 89. 17% (107/120), the positive rate of anti-HCV NS4 is 70. 83% (85/120), the positive rate of anti-HCV NS5 is 52.50% (63/120).</p>
Subject(s)
Adolescent , Adult , Aged , Child , Female , Humans , Male , Middle Aged , Young Adult , Clinical Laboratory Techniques , Methods , Fluorescent Antibody Technique , Methods , Hepacivirus , Chemistry , Hepatitis C , Blood , Diagnosis , Virology , Hepatitis C Antibodies , Blood , Chemistry , Microspheres , Protein Array Analysis , Methods , Quantum Dots , Viral Core Proteins , ChemistryABSTRACT
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.
Subject(s)
Adolescent , Adult , Child , Female , Humans , Male , Middle Aged , Young Adult , Anemia, Aplastic , Allergy and Immunology , Metabolism , Case-Control Studies , Cell Proliferation , Cells, Cultured , Interferon-gamma , Metabolism , Interleukin-4 , Metabolism , Strychnine , Pharmacology , T-Lymphocytes , Cell Biology , Bodily Secretions , Tumor Necrosis Factor-alpha , MetabolismABSTRACT
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.