ABSTRACT
OBJECTIVE: To assess the cytotoxic activities of crude extracts and solvent fractions of Spermacoce verticillata, Ficus pumila and Flemingia strobilifera against a MT-4 human leukaemia cancer cell line. METHODS: Crude extracts of dried leaves of S verticillata, F pumila and F strobilifera were made by exhaustive methanol extraction, fractions were obtained from sequential extraction of the crude extract using solvents of increasing polarity. Dose responses corresponding to cell survival following 72-hour exposure to the extracts were determined using a leukaemia cancer cell line (MT-4). Cell viability was assessed using the MTT[3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide] assay reading absorbances at 570 nm. Comparisons were made with controls and cell survival, in each sample well, was determined based on the ratio ofthe absorbance ofthe sample to the control. RESULTS: Crude extracts of S verticillata, F pumila and F strobilifera displayed cytotoxicity and the IC50 values were 89 µ/ml, 131 µ/ml and 81 µ/ml, respectively. The petroleum ether and chloroform fractions ofthe crude extracts of S verticillata and F strobilifera showed potent cytotoxic activity but the highest cytotoxic activity was found in the chloroform and butanol fractions of F pumila with IC50 values of 23 µg/ml and 26 µg/ml, respectively. CONCLUSION: The crude extracts of S verticillata, F pumila and F strobilifera were shown to be cytotoxic to the leukaemia cell line, MT-4 and IC50 values were determined. Fractionation of the crude extracts by solvent-solvent extraction enabled determination of the active fractions and their IC50 values. We propose that cytotoxic activity may be due to antioxidant compounds previously isolated from these plants.
OBJETIVO: Evaluar las actividades citotóxica de extractos crudos y las fracciones solventes de Spermacoce verticillata, Ficus pumila y Flemingia strobilifera contra una línea celular de la leucemia humana MT4. MÉTODOS: Se obtuvieron extractos crudos de hojas secas de S verticillata, F pumila y F strobilifera mediante extracción exhaustiva con etanol, y se obtuvieron fracciones a partir de la extracción secuencial del extracto crudo mediante solventes de polaridad creciente. Se determinaron las respuestas a las dosis correspondientes a la sobrevivencia de las células luego de 72 horas de exposición a los extractos, usando una línea celular de leucemia (MT-4). La viabilidad celular fue evaluada usando lecturas de absorbancia a partir del ensayo MTT [3-(4, 5-dimetiltiazol-2-il)-2, 5-difenil tetrazolio bromuro] a 570 nm. Se hicieron comparaciones con los controles. La sobrevivencia celular en cada pozo de muestreo, fue determinada a partir de la tasa de absorbancia de la muestra con respecto al control. RESULTADOS: Los extractos crudos de S verticillata, F pumila y F strobilifera mostraron citotoxicidad y los valores IC50 fueron 89 µ/ml, 131 µ/ml y 81 µ/ml, respectivamente. El éter de petróleo y las fracciones de cloroformo de los extractos crudos de S verticillata y F strobilifera mostraron una potente actividad citotóxica, pero la actividad citotóxica más alta fue hallada en las fracciones de cloroformo y butanol de F pumila con valores IC50 de 23 µ/ml y 26 µ/ml, respectivamente. CONCLUSIÓN: Los extractos de S verticillata, F pumila y F strobilifera demostraron ser citotóxicos a la línea celular MT4 y IC50 se determinaron los valores. El fraccionamiento de los extractos crudos extractos mediante extracción solventes-solventes hizo posible la determinación de las fracciones activas y sus valores IC50. Sugerimos que la actividad citotóxica puede deberse a compuestos antioxidantes previamente aislados a partir de estas plantas.
Subject(s)
Humans , Antineoplastic Agents, Phytogenic/pharmacology , Leukemia/drug therapy , Phytotherapy , Plant Extracts/pharmacology , Plants, Medicinal , Cell Line, Tumor , Cell Survival/drug effects , Fabaceae/chemistry , Ficus/chemistry , Medicine, Traditional , Plant Leaves , Rubiaceae/chemistry , West IndiesABSTRACT
Purpose:To explore the effect of anti-FasL on ADM resistance of K562/ADM cell subline and its possible mechanism.Methods:Control group,untreated with VER or anti-FasL ,VER-treated group,anti-FasL-treated group and anti-FasL +VER-treated group were set up. MTT、FCM、TUNEL、S-P immunechemistry and RT-PCR assay were used for detection.Results:Anti-FasL or VER treatment was capable of strengthening sensitivity of K562/ADM cells to ADM,ID 50 of anti-FasL and VER was 200ng/ml and 6?g/ml,respectively;DNA content of apoptosis from cycling analysis curve of K562/ADM cell was 7.42%,32.10%,49.29%,56.26%,respectively,and positive rate in situ apoptosis was 4.5%,36%,45%,58%,respectively,which represented a tendency of gradual increase. Anti-FasL was capable of effecting FasL and bcl-2 expression,but not Pgp.Conclusions:Anti-FasL alone or synergically with VER was capable of reversing ADM resistance of K562/ADM cell,which may be used as a novel reversor of multidrug resistance.
ABSTRACT
1 ? 25-dihydroxy-vitamin D3(1? 25 (OH)2 D3)induced differentiation of human promyelocytic leukaemia cells ( HL-60 ) into mature myeloid cells in vitro. The ratio of nuclei to cytoplasma decreased; Their nucleoli reduced; Cells became irrgular and extended the pseudopods. 1 ? 25 (OH ) 2 D3 caused significant increase of nitroblue tetrazolium ( NBT ) reduction and ?-non-specific acid esterase (?-NAE ) and acid phosphatase (ACP ) activities. These data and morphological characteristics suggest that HL-60 cells were conclusively identified as monocytes/macrophages. The histogram of DNA distribution ahylyzed by flow cytometry demonstrated G0 + G1 phase increased and S phase increased and S phase decreased remarkably after treatment with l?, 25 ( OH ) 2 D3 as compared with untreated cells.