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1.
Braz. J. Pharm. Sci. (Online) ; 58: e191042, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1394057

RESUMO

Abstract L-Asparaginase (L-ASNase) is a biopharmaceutical used for acute lymphoblastic leukaemia (ALL) treatment, dramatically increasing the patients' chance of cure. However, its production and distribution in developing countries were disrupted because of its low profitability, which caused great concern among patients. This study evaluates the feasibility of combining fractional precipitation and aqueous two-phase systems (ATPS) to purify L-ASNase from a low-grade product, commercially known as Acrylaway® L. The ATPS purification results were not particularly expressive compared to the two-step purification process composed of ethanol precipitation and gel filtration, which was able to recover the target molecule with a purification factor over 5 fold. Thus, we studied a purification process capable of manufacturing pharmaceutical grade L-ASNase from a commercially available low-grade raw material; however, improvements regarding its throughput must be achieved, and high purity is the first step to apply it as a new biopharmaceutical product. The proposed process could pose as a short-time solution to mitigate its shortage while a cost-effective production plant is being developed.


Assuntos
Asparaginase/isolamento & purificação , Precipitação Fracionada/métodos , Antineoplásicos/isolamento & purificação , Estudos de Viabilidade , Cromatografia em Gel , Análise Custo-Benefício
2.
Rev. bras. parasitol. vet ; 28(1): 126-133, Jan.-Mar. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-990809

RESUMO

Abstract The antitumor properties of ticks salivary gland extracts or recombinant proteins have been reported recently, but little is known about the antitumor properties of the secreted components of saliva. The goal of this study was to investigate the in vitro effect of the saliva of the hard tick Amblyomma sculptum on neuroblastoma cell lines. SK-N-SK, SH-SY5Y, Be(2)-M17, IMR-32, and CHLA-20 cells were susceptible to saliva, with 80% reduction in their viability compared to untreated controls, as demonstrated by the methylene blue assay. Further investigation using CHLA-20 revealed apoptosis, with approximately 30% of annexin-V positive cells, and G0/G1-phase accumulation (>60%) after treatment with saliva. Mitochondrial membrane potential (Δψm) was slightly, but significantly (p < 0.05), reduced and the actin cytoskeleton was disarranged, as indicated by fluorescent microscopy. The viability of human fibroblast (HFF-1 cells) used as a non-tumoral control decreased by approximately 40%. However, no alterations in cell cycle progression, morphology, and Δψm were observed in these cells. The present work provides new perspectives for the characterization of the molecules present in saliva and their antitumor properties.


Resumo As propriedades antitumorais de extratos de glândulas salivares de carrapatos ou proteínas recombinantes foram relatadas recentemente, mas pouco se sabe sobre as propriedades antitumorais dos componentes secretados da saliva. O objetivo deste estudo foi investigar o efeito in vitro da saliva bruta do carrapato duro Amblyomma sculptum sobre as linhagens celulares de neuroblastoma. Células SK-N-SK, SH-SY5Y, Be(2)-M17, IMR-32 e CHLA-20 foram suscetíveis à saliva, com redução de 80% na sua viabilidade em comparação com controles não tratados, como demonstrado pelo ensaio de Azul de Metileno. Investigações posteriores utilizando CHLA-20 revelaram apoptose, com aproximadamente 30% de células positivas para anexina-V, e G0/G1 (> 60%) após tratamento com saliva. O potencial de membrana mitocondrial (Δψm) foi reduzido significativamente (p <0,05), e o citoesqueleto de actina foi desestruturado, como indicado pela microscopia de fluorescência. A viabilidade do fibroblasto humano (células HFF-1), usado como controle não tumoral, diminuiu em aproximadamente 40%. No entanto, não foram observadas alterações na progressão do ciclo celular, morfologia e Δψm nestas células. O presente trabalho fornece novas perspectivas para a caracterização das moléculas presentes na saliva e suas propriedades antitumorais.


Assuntos
Animais , Saliva/química , Produtos Biológicos/farmacologia , Citoesqueleto/efeitos dos fármacos , Ixodidae/química , Proteínas de Artrópodes/farmacologia , Neuroblastoma/patologia , Antineoplásicos/farmacologia , Produtos Biológicos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proteínas de Artrópodes/isolamento & purificação , Antineoplásicos/isolamento & purificação
3.
Biol. Res ; 52: 55-55, 2019. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-1505775

RESUMO

BACKGROUND: Epanorin (EP) is a secondary metabolite of the Acarospora lichenic species. EP has been found in lichenic extracts with antimicrobial activity, and UV-absorption properties have been described for closely related molecules; however, its antiproliferative activity in cancer cells has not yet been explored. It has been hypothesized that EP inhibits cancer cell growth. MCF-7 breast cancer cells, normal fibroblasts, and the non-transformed HEK-293 cell line were exposed to increasing concentrations of EP, and proliferation was assessed by the sulforhodamine-B assay. RESULTS: MCF-7 cells exposed to EP were examined for cell cycle progression using flow cytometry, and DNA fragmentation was examined using the TUNEL assay. In addition, EP's mutagenic activity was assessed using the Salmonella typhimurium reverse mutation assay. The data showed that EP inhibits proliferation of MCF-7 cells, and it induces cell cycle arrest in G0/G1 through a DNA fragmentation-independent mechanism. Furthermore, EP's lack of overt cytotoxicity in the normal cell line HEK-293 and human fibroblasts in cell culture is supported by the absence of mutagenic activity of EP. CONCLUSION: EP emerges as a suitable molecule for further studies as a potential antineoplastic agent.


Assuntos
Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Líquens/química , Antineoplásicos/uso terapêutico , Fragmentação do DNA , Células MCF-7 , Citometria de Fluxo , Antineoplásicos/isolamento & purificação
4.
An. acad. bras. ciênc ; 89(3): 1369-1379, July-Sept. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886755

RESUMO

ABSTRACT Natural steroids and triterpenes such as b-sitosterol, stigmasterol, lupeol, ursolic and betulinic acids were transformed into its hexanoic and oleic esters, to evaluate the influence of chemical modification towards the cytotoxic activities against tumor cells. The derivatives were evaluated against five tumor cell lines [OVCAR-8 (ovarian carcinoma); SF-295 (glioblastoma); HCT-116 (colon adenocarcinoma); HL-60 (leukemia); and PC-3 (prostate carcinoma)] and the results showed only betulinic acid hexyl ester exhibits cytotoxic potential activity.


Assuntos
Humanos , Triterpenos/farmacologia , Lamiaceae/química , Triterpenos Pentacíclicos/farmacologia , Fabaceae/química , Antineoplásicos/farmacologia , Triterpenos/isolamento & purificação , Triterpenos/química , Ensaios de Seleção de Medicamentos Antitumorais , Lamiaceae/classificação , Concentração Inibidora 50 , Linhagem Celular Tumoral , Ésteres , Triterpenos Pentacíclicos/isolamento & purificação , Triterpenos Pentacíclicos/química , Fabaceae/classificação , Antineoplásicos/isolamento & purificação , Antineoplásicos/química
5.
Indian J Exp Biol ; 2015 Feb; 53(2): 98-103
Artigo em Inglês | IMSEAR | ID: sea-158385

RESUMO

Anticancer potential of Moringa oleifera L. extracts have been well established. However, there are no reports on the isolated molecules/fractions from these extracts which are responsible for the anticancer/cytotoxic activity. Thus, in the present study, we explored the same. The n-hexane, chloroform, ethyl acetate, methanol extracts of the M. oleifera leaves and 15 fractions (F1 to F15) of ethyl acetate extract were evaluated for their in vitro and in vivo anticancer activity using Hep-2 cell lines and Dalton’s lymphoma ascites model in mice, respectively. Among the tested samples, the F1 fraction showed potential cytotoxic effect in Hep-2 cell lines with a CTC50 value of 12.5 ± 0.5 µg/ml. In vivo studies with the doses 5 and 10 mg/kg, p.o. demonstrated significant reduction in body weight and increased the mean survival time compared to the control group. These results were also comparable to the standard, 5-Fluorouracil, treated animals. We have also successfully isolated and characterized the anticancer fraction, F1 from the leaves of M. oleifera L.


Assuntos
Acetatos/química , Animais , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Fracionamento Químico/métodos , Clorofórmio/química , Feminino , Células Hep G2 , Hexanos/química , Humanos , Concentração Inibidora 50 , Metanol/química , Moringa oleifera/química , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Análise de Sobrevida , Fatores de Tempo , Células Vero
6.
Biol. Res ; 48: 1-10, 2015. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-950822

RESUMO

BACKGROUND: Actinomycetes are gram positive bacteria with high G + C content in their DNA and are capable of producing variety of secondary metabolites. Many of these metabolites possess different biological activities and have the potential to be developed as therapeutic agents. The aim of the present study was to screen actinomycetes inhabiting halophilic environment such as Khewra salt mines present in Pakistan for cytotoxic and antitumor compounds. RESULTS: An actiomycetes strain designated as Streptomyces sp. KML-2 was isolated from a saline soil of Khewra salt mines, Pakistan. The strain Streptomyces sp. KML-2 showed 84 % cytotoxic activity against larvae of Artemiasalina. In the screening phase, the strain exhibited significant antitumor activity with IC50 values of 12, 48 and 56 µg/ml against Hela, MDBK and Vero cell lines, respectively. After that extract from 20 l fermentation was used to purify secondary metabolites by several chromatographic techniques. Structure elucidation of isolated compounds revealed that it is highly stable producer of Chromomycin SA (1) and 1-(1H-indol-3-yl)-propane-1,2,3-triol (2). Both of the isolated compounds showed significant antitumor activity against Hela and MCF-7 cancer cell lines (IC50 values 8.9 and 7.8 µg/ml against Hela; 12.6 and 0.97 µg/ml against MCF-7, respectively). The 16S rRNA gene sequence (1437 bp) of the strain confirm its identity (99 %) with Streptomyces griseus. CONCLUSIONS: From this research work we were successful in isolating two potent antitumor compounds, Chromomycin SA and 1-(1H-indol-3-yl)-propane-1,2,3-triol from Streptomyces KML-2 strain, isolated from Khewra salt mine. As such this is the second report which confirms that S. griseus can produce Chromomycin SA without introducing any mutagenesis in its biosynthesizing gene cluster and isolated indole derivative is being reported first time from any member of actinomycetes group with having novel antitumor activity against Hela and MCF-7 cells Nucleotide sequences: Nucleotide sequence data reported are available in the GenBank database under the accession number: GenBank KJ009562.


Assuntos
Humanos , Animais , Bovinos , Microbiologia do Solo , Streptomyces/química , Antineoplásicos/farmacologia , Paquistão , Filogenia , Artemia/classificação , Artemia/efeitos dos fármacos , Sais , Solo/química , Streptomyces/isolamento & purificação , Streptomyces/ultraestrutura , Streptomyces griseus/classificação , Sais de Tetrazólio , Células Vero , RNA Ribossômico 16S/genética , Cromomicinas/classificação , Cromomicinas/farmacologia , Células HeLa , Microscopia Eletrônica de Varredura , Linhagem Celular , Chlorocebus aethiops , Cromatografia/métodos , Análise de Sequência de RNA , Concentração Inibidora 50 , Células MCF-7 , Formazans , Glicerol/análogos & derivados , Glicerol/farmacologia , Larva/efeitos dos fármacos , Mineração , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antineoplásicos/isolamento & purificação
7.
Indian J Biochem Biophys ; 2014 Feb; 51(1): 46-51
Artigo em Inglês | IMSEAR | ID: sea-154230

RESUMO

In vitro cytotoxic potential of extracts (95% and 50% ethanolic extract and hot water extract at concentration of 100 µg/ml) from leaves of Holarrhena antidysenterica was evaluated against fourteen human cancer cell lines — A-549, COLO-205, DU-145, HeLa, HEP-2, IMR-32, KB, MCF-7, NCI-H23, OVCAR-5, SiHa, SK-N-MC, SW-620 and ZR-75-1 from nine different tissues (breast, colon, cervix, CNS, lung, liver, oral, ovary and prostate) using SRB assay. The 95% ethanolic extract displayed maximum anti-proliferative effect in the range of 73-92% against eight human cancer cell lines, while 50% ethanolic extract showed cytotoxic activity in the range of 70-94% against seven human cancer cell lines. However, the hot water extract did not show any activity. Among the fractions of 95% and 50% ethanolic extract, significant cytotoxic activity was found in the chloroform soluble fraction of 95% ethanolic extract at 100 µg/ml; it inhibited the growth in the range of 71-99% of seven human cancer cell lines from five different tissues viz., OVCAR-5 (ovary), HT-29 (colon), SK-N-MC (neuroblastoma), HEP-2 (liver), COLO-205 (colon), NIH-OVCAR-3 (ovary) and A-549 (lung). The cytotoxic activity of chloroform soluble fraction was found to be higher than 5-flurouracil, adriamycin, mitomycin-c and paclitaxel (anticancer drugs used as positive controls). Further in vivo studies and identification of active components from the chloroform fraction and their exact mechanism of action could be useful in designing new anticancer therapeutic agents.


Assuntos
Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Holarrhena/química , Humanos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Folhas de Planta/química
8.
Braz. j. microbiol ; 44(4): 1059-1065, Oct.-Dec. 2013. graf, tab
Artigo em Inglês | LILACS | ID: lil-705282

RESUMO

Polysaccharides with medicinal properties can be obtained from fruiting bodies, mycelium and culture broth of several fungus species. This work was carried out in batch culture using a stirred tank reactor with two different initial glucose concentrations (40-50 g/L) and pH values (3.0-4.0) to enhance extracellular polysaccharides production by Pleurotus djamor UNIVILLE 001 and evaluate antitumor effect of intraperitonial administration of Pleurotus djamor extract on sarcoma 180 animal model. According to factorial design, the low pH value (pH 3.0) led to a gain of 1.6 g/L on the extracellular polysaccharide concentration, while glucose concentration in the tested range had no significant effect on the concentration of polysaccharide. With 40 g/L initial glucose concentration and pH 3.0, it was observed that yield factor of extracellular polysaccharide on substrate (Y P/S = 0.072) and maximum extracellular polysaccharide productivity (Q Pmax = 11.26 mg/L.h) were about 188% and 321% respectively higher than those obtained in the experiment performed at pH 4.0. Under these conditions, the highest values of the yield factor of biomass on substrate (Y X/S = 0.24) and maximal biomass productivity (Q Xmax = 32.2 mg/L.h) were also reached. In tumor response study, mean tumor volume on the 21th day was 35.3 cm³ in untreated group and 1.6 cm³ in treated group (p = 0.05) with a tumor inhibition rate of 94%. These impressive results suggests an inhibitory effect of P.djamor extract on cancer cells.


Assuntos
Animais , Masculino , Camundongos , Antineoplásicos/isolamento & purificação , Antineoplásicos/uso terapêutico , Pleurotus/metabolismo , Polissacarídeos/isolamento & purificação , Polissacarídeos/uso terapêutico , Sarcoma/tratamento farmacológico , Antineoplásicos/metabolismo , Brasil , Meios de Cultura/química , Modelos Animais de Doenças , Glucose/metabolismo , Concentração de Íons de Hidrogênio , Injeções Intraperitoneais , Pleurotus/isolamento & purificação , Polissacarídeos/metabolismo , Resultado do Tratamento
9.
Braz. j. med. biol. res ; 46(1): 65-70, 11/jan. 2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-665798

RESUMO

Natural products produced by microorganisms have been an important source of new substances and lead compounds for the pharmaceutical industry. Chromobacterium violaceum is a Gram-negative β-proteobacterium, abundant in water and soil in tropical and subtropical regions and it produces violacein, a pigment that has shown great pharmaceutical potential. Crude extracts of five Brazilian isolates of Chromobacterium sp (0.25, 2.5, 25, and 250 µg/mL) were evaluated in an in vitro antitumor activity assay with nine human tumor cells. Secondary metabolic profiles were analyzed by liquid chromatography and electrospray ionization mass spectrometry resulting in the identification of violacein in all extracts, whereas FK228 was detected only in EtCE 308 and EtCE 592 extracts. AcCE and EtCE 310 extracts showed selectivity for NCI/ADR-RES cells in the in vitro assay and were evaluated in vivo in the solid Ehrlich tumor model, resulting in 50.3 and 54.6% growth inhibition, respectively. The crude extracts of Chromobacterium sp isolates showed potential and selective antitumor activities for certain human tumor cells, making them a potential source of lead compounds. Furthermore, the results suggest that other compounds, in addition to violacein, deoxyviolacein and FK228, may be involved in the antitumor effect observed.


Assuntos
Animais , Humanos , Masculino , Camundongos , Antineoplásicos/farmacologia , Chromobacterium/metabolismo , Indóis/farmacologia , Neoplasias Experimentais/tratamento farmacológico , Antineoplásicos/isolamento & purificação , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Misturas Complexas , Indóis/isolamento & purificação , Indóis/uso terapêutico , Espectrometria de Massas por Ionização por Electrospray
10.
The Korean Journal of Parasitology ; : 711-717, 2013.
Artigo em Inglês | WPRIM | ID: wpr-197168

RESUMO

Opisthorchis viverrini (O. viverrini) is a well-known causative agent of cholangiocarcinoma (CCA) in humans. CCA is very resistant to chemotherapy and is frequently fatal. To understand the pathogenesis of CCA in humans, a rodent model was developed. However, the development of CCA in rodents is time-consuming and the xenograft-transplantation model of human CCA in immunodeficient mice is costly. Therefore, the establishment of an in vivo screening model for O. viverrini-associated CCA treatment was of interest. We developed a hamster CCA cell line, Ham-1, derived from the CCA tissue of O. viverrini-infected and N-nitrosodimethylamine-treated Syrian golden hamsters. Ham-1 has been maintained in Dulbecco's Modified Essential Medium supplemented with 10% fetal bovine serum for more than 30 subcultures. These cells are mostly diploid (2n=44) with some being polyploid. Tumorigenic properties of Ham-1 were demonstrated by allograft transplantation in hamsters. The transplanted tissues were highly proliferative and exhibited a glandular-like structure retaining a bile duct marker, cytokeratin 19. The usefulness of this for in vivo model was demonstrated by berberine treatment, a traditional medicine that is active against various cancers. Growth inhibitory effects of berberine, mainly by an induction of G1 cell cycle arrest, were observed in vitro and in vivo. In summary, we developed the allo-transplantable hamster CCA cell line, which can be used for chemotherapeutic drug testing in vitro and in vivo.


Assuntos
Animais , Cricetinae , Masculino , Aloenxertos , Antineoplásicos/isolamento & purificação , Berberina/uso terapêutico , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Transplante de Células/métodos , Colangiocarcinoma/tratamento farmacológico , Meios de Cultura/química , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Mesocricetus
11.
Indian J Biochem Biophys ; 2011 June; 48(3): 141-147
Artigo em Inglês | IMSEAR | ID: sea-135311

RESUMO

This is the first report of three different fusion proteins with an antitumor-analgesic peptide obtained from Chinese scorpion Buthus martensii Karsch (BmKAGAP). The fusion proteins were constructed in the form of chimeric toxins, aiming to obtain bifunctional analgesic and antitumor activity. The fusion proteins consisted of luteinizing hormone-releasing hormone (LHRH), three different types of flexible linkers (L1, Ser-Ser-His-His-His-His-His-His-Ser-Ser-Gly-Leu-Val-Pro-Arg-Gly-Ser-His-Met; L2, Gly-Gly-Gly-Ser-Gly-Gly-Gly-Ser; L3, Ser-Gly-Gly-Ser-Gly-Gly-Ser-Gly-Gly-Gly-Ser-Ser-Gly-Gly-Ser-Gly-Gly-Gly-Gly-Ser-Gly-Gly-Gly-Gly-Ser), and BmKAGAP. The genes coding three fusion proteins were cloned and expressed in E. coli in soluble form. Following two successive column chromatographic separations, purified fusion proteins were obtained. These fusion proteins exhibited analgesic activity in mice and were cytotoxic to a hepatocellular carcinoma cell line Hep3B.


Assuntos
Analgésicos/administração & dosagem , Analgésicos/isolamento & purificação , Analgésicos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Camundongos , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/farmacologia , Venenos de Escorpião/administração & dosagem , Venenos de Escorpião/biossíntese , Venenos de Escorpião/química , Venenos de Escorpião/isolamento & purificação , Venenos de Escorpião/farmacologia , Escorpiões
12.
The Korean Journal of Parasitology ; : 175-177, 2009.
Artigo em Inglês | WPRIM | ID: wpr-156336

RESUMO

Cancer is the main cause of death in developed countries. However, in underdeveloped countries infections and parasitic diseases are the main causes of death. There are raising scientific evidences indicating that parasitic infections induce antitumor activity against certain types of cancers. In this study, the effects of Toxoplasma gondii and Toxocara canis egg antigens in comparison with Bacillus Calmette Guerin (BCG) (known to have anticancer distinctive) on WEHI-164 fibosarcoma transplanted to BALB/c mice was investigated. Groups of 6 male BALB/c mice injected with T. gondii antigen, BCG, or T. canis egg antigen as case groups and alum alone as control groups. All mice were then challenged with WEHI-164 fibrosarcoma cells. The mice were examined for growth of the solid tumor and the tumor sizes were measured every other day up to 4 wk. The mean tumor area in T. gondii, BCG, or alum alone injected mice in 4 different days of measurements was 25 mm2, 23 mm2, and 186 mm2 respectively. Also the mean tumor area in T. canis injected mice in 4 different days was 25.5 mm2 compared to the control group (alum treated) which was 155 mm2. T. gondii parasites and T. canis egg antigens induced inhibition of the tumor growth in the fibrosarcoma mouse model. We need further study to clarify the mechanisms of anti-cancer effects.


Assuntos
Animais , Feminino , Masculino , Camundongos , Antígenos de Helmintos/isolamento & purificação , Antígenos de Protozoários/isolamento & purificação , Antineoplásicos/isolamento & purificação , Quimioprevenção/métodos , Fibrossarcoma/patologia , Camundongos Endogâmicos BALB C , Mycobacterium bovis , Toxocara canis/química , Toxoplasma/química
13.
Braz. j. med. biol. res ; 40(11): 1545-1555, Nov. 2007. ilus, tab
Artigo em Inglês | LILACS | ID: lil-464302

RESUMO

Agaricus blazei Murill is a native Brazilian mushroom which functions primarily as an anticancer substance in transplanted mouse tumors. However, the mechanism underlying this function of A. blazei Murill remains obscure. The present study was carried out to investigate the effect of fraction FA-2-b-ß, an RNA-protein complex isolated from A. blazei Murill, on human leukemia HL-60 cells in vitro. Typical apoptotic characteristics were determined by morphological methods using DNA agarose gel electrophoresis and flow cytometry. The growth suppressive effect of fraction FA-2-b-ß on HL-60 cells in vitro occurred in a dose- (5-80 mug/mL) and time-dependent (24-96 h) manner. The proliferation of HL-60 cells (1 x 10(5) cells/mL) treated with 40 mug/mL of fraction FA-2-b-ß for 24-96 h and with 5-80 mug/mL for 96 h resulted in inhibitory rates ranging from 8 to 54.5 percent, and from 4.9 to 86.3 percent, respectively. Both telomerase activity determined by TRAP-ELISA and mRNA expression of the caspase-3 gene detected by RT-PCR were increased in HL-60 cells during fraction FA-2-b-ß treatment. The rate of apoptosis correlated negatively with the decrease of telomerase activity (r = 0.926, P < 0.05), but correlated positively with caspase-3 mRNA expression (r = 0.926, P < 0.05). These data show that fraction FA-2-b-ß can induce HL-60 cell apoptosis and that the combined effect of down-regulation of telomerase activity and up-regulation of mRNA expression of the caspase-3 gene could be the primary mechanism of induction of apoptosis. These findings provide strong evidence that fraction FA-2-b-ß could be of interest for the clinical treatment of acute leukemia.


Assuntos
Humanos , Agaricus/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , RNA Fúngico/química , Proteínas de Ligação a RNA/farmacologia , Antineoplásicos/isolamento & purificação , /análise , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Eletroforese em Gel de Ágar , /efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Reação em Cadeia da Polimerase Via Transcriptase Reversa , RNA Fúngico/isolamento & purificação , RNA Mensageiro/química , Proteínas de Ligação a RNA/isolamento & purificação , Fatores de Tempo , Telomerase/análise
14.
J Environ Biol ; 2007 Jul; 28(3): 645-50
Artigo em Inglês | IMSEAR | ID: sea-113712

RESUMO

The actinomycete strain LA-29 isolated from the gut contents of the fish, Mugil cephalus of the Vellar estuary showed excellent L-asparaginase activity The enzyme was purified 18-fold and the final recovery of protein was 1.9%, which exhibited an activity of 13.57 IU/mg protein. The partially purified L-asparaginase inhibited the growth of leukemia cells in male wistar rats. Average survival period of the rats was more in an optimum enzyme dose of 100 units and the survival period was less when the dosages were increased and at the same time the enzyme became less effective when the dosages were decreased. Higher survival of 17.2 days was recorded when 100 units of the enzyme was given in three intermittent doses (50/25/25 units) at the interval of 24 hr. Analysis of cell components of the strain LA-29 has revealed the wall type-I which is the characteristic of the genus Streptomyces. Further the morphological, physiological and biochemical features along with the micromorphological results obtained for the strain LA-29 were compared with that of the Streptomyces species found in Bergey's Manual of Determinative Bacteriology and the strain LA-29 has been tentatively identified as Streptomyces canus.


Assuntos
Actinobacteria/enzimologia , Animais , Antineoplásicos/isolamento & purificação , Asparaginase/isolamento & purificação , Linhagem Celular Tumoral , Conteúdo Gastrointestinal/microbiologia , Leucemia/tratamento farmacológico , Masculino , Transplante de Neoplasias , Ratos , Ratos Wistar , Smegmamorpha/microbiologia
15.
Clinics ; 62(6): 763-768, 2007.
Artigo em Inglês | LILACS | ID: lil-471797

RESUMO

Plants have played a significant role in the treatment of cancer and infectious diseases for the last four decades. The discovery and introduction to market of paclitaxel, the vinca alkaloids, etoposide, and many antibacterial drugs support drug discovery programs based on natural products. Natural products have been rediscovered as important tools for drug development despite advances in combinatorial chemistry, due to the complex molecular structures able to interact with mammalian cell targets. The Brazilian flora, the most diverse in the world, has become an interesting spot to prospect for new chemical leads or hits due to its species diversity and associated chemical richness. Screening programs have been established in Brazil as a strategy to identify potentially active substances. High throughput screening techniques allow for the analysis of large numbers of extracts in a relatively short period of time, and can be considered one of the most efficient ways of finding new leads from natural products. An updated review of the current status of the biological screening program is presented and recent results from new antitumoral and antibacterial chemical leads are discussed.


Plantas são uma importante fonte de novos protótipos há pelo menos quatro décadas. A descoberta e introdução no mercado de paclitaxel, dos alcalóides da vinca, etoposídeo e muitos agentes antibacterianos têm servido de apoio ao desenvolvimento de programas de descobrimento de novos fármacos baseados em produtos naturais. Produtos naturais foram recentemente redescobertos como importante ferramenta na descoberta de novos fármacos devido às estruturas moleculares complexas capazes de interagir com alvos em células de mamíferos. A flora brasileira, a mais rica do mundo, tornou-se um importante sítio para prospecção de novos protótipos em decorrência da riqueza de espécies vegetais relacionada a uma possível diversidade química. Programas de triagem têm sido introduzidos no Brasil contrapondo a devastação de florestas relacionadas a atividades rurais, extrativismo madeireiro e mineral. Ensaios em larga escala permitem a análise de um grande número de amostras em um tempo relativamente pequeno, e pode ser considerado como o método mais eficaz para a descoberta de novos fármacos a partir de plantas. Dados atualizados relativos a programas de triagem que objetivam a identificação de novos protótipos antitumorais e antibacterianos são comentados.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Descoberta de Drogas , Extratos Vegetais/química , Plantas Medicinais/química , Tecnologia Farmacêutica , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Biodiversidade , Brasil , Desenho de Fármacos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Árvores
16.
Experimental & Molecular Medicine ; : 111-120, 2005.
Artigo em Inglês | WPRIM | ID: wpr-90141

RESUMO

We purified phytoestrogens from Pueraria root (Pueraria mirifica from Thailand and Pueraria lobata from Korea), which is used as a rejuvenating folk medicine in Thailand and China. Dried, powdered plant material was extracted with 100% ethanol and further separated by concentration, filtration, and thin layer silica gel chromatography. Using the fractions obtained during separation, we first investigated their cytotoxicity in several cancer cell lines from various tissues. The ethanol-extracted components (PE1, PE4) had significant antiproliferative effects on breast cancer cell lines, including MCF-7, ZR-75-1, MDA-MB-231, SK-BR-3, and Hs578T. Second, we compared these results with the cytotoxic effects of known flavonoids, sterols, and coumarins from Pueraria root. The known compounds were not as effective, and occurred in a different polarity region on HPLC. Third, further separation resulted in the isolation of eight different components (Sub PE-A to -H). One of these, PE-D, affected the growth of some breast cancer cell lines (MCF-7, MDA-MB-231) in a dose- and time-dependent manner, as well as the growth of ovarian (2774) and cervical cancer cells (HeLa). Finally, a transfection assay showed that this component had an estrogenic effect similar to 17beta-estradiol, which activates both estrogen receptor a (ER alpha) and ER beta. The NMR analysis determined that spinasterol (stigmasta-7, 22-dien-3beta-ol) is an active cytotoxic component of Pueraria root.


Assuntos
Feminino , Humanos , Antineoplásicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Receptor alfa de Estrogênio/agonistas , Receptor beta de Estrogênio/agonistas , Preparações de Plantas/uso terapêutico , Raízes de Plantas/química , Pueraria/química , Estigmasterol/análogos & derivados , Transfecção , Células Tumorais Cultivadas
17.
Journal of Medicinal Plants. 2005; 4 (15): 59-65
em Persa | IMEMR | ID: emr-72110

RESUMO

A growing body of research has confirmed that saffron stigma extract and its main constituents have anticancer properties. The aim of the present study was to evaluate the possible cytotoxic and anti-tumor activities of the ethanolic extracts of Crocus sativus stigma and petal using simple brine shrimp and potato disc assays. The MIC of stigma and petal extracts were determined using microplate method. In brine shrimp assay, for each concentration, three wells containing 10 larva were tested. After 24h, the number of dead larva were counted. In potato disc assay, discs were cut of potato with specific diameter and transferred onto 1.5% agar under a laminar air cabinet. 50 micro1 of a mixture containing suspension of Agrobacterium tumefaciens and the solution of stigma and petal extracts were inoculated on potato discs in plates. The plates were incubated at 25°C for 21 days, and the tumors were counted. The MIC of stigma extract was 10 mg/ml. The Petal extract did not show any antibacterial activity in the of concentration range 1-16 mg/ml. The IC50 values of stigma and petal extracts against tumor were 5.3 and 10.8 mg/ml, respectively. The LC50 values of stigma and petal extracts against brine shrimp were 1678.7 and 1356.8 ppm, respectively. This study indicated that the ethanolic extracts of saffron stigma and petal have anti-tumor activity and the stigma extract has more potent anti-tumor efects than the petal extract but with less toxicity


Assuntos
Crocus/química , Antineoplásicos/biossíntese , Antineoplásicos/isolamento & purificação , Artemia , Extratos Vegetais , Extratos Vegetais/isolamento & purificação
19.
Biocell ; 24(2): 139-144, Aug. 2000.
Artigo em Inglês | LILACS | ID: lil-335903

RESUMO

Callus culture of Taxus baccata and Taxus x Media were induced using explants of young stems and female gametophyte. Culture conditions have been established for the cell suspension of the different callus cell lines. Callus were induced from Taxus baccata and Taxus x Media using Murashige and Skoog (MS) medium supplemented with different concentrations of 2,4 D (2,4-dichlorophenoxyacetic) and benzylaminopurine (BA). All the cultures grew slowly following the first subculture and the majority turned brown and ceased growth. The fast growing callus lines constituted a habituated callus lines (CFGTB; CFGTM; CSTB and CSTB). These callus lines were used to induce cell suspension in the best nutritional medium (1 mg/l 2,4-D and 0.1 mg/l BA). The callus exhibited levels of taxol ranging from 0.1 to 15 mg/Kg on a dry weight basis. Suspension cultures of Taxus baccata (CSTB and CFGTB) and Taxus x Media (CSTM and CFGTM) were maintained at 25 degrees C on a MS medium with two weeks transfers. The maximum taxol production for suspension cell was within the range 5 to 6 mg/l.


Assuntos
Antineoplásicos/isolamento & purificação , Técnicas de Cultura de Células , Paclitaxel , Plantas Medicinais , Taxus , Linhagem Celular , Ácidos Indolacéticos , Taxus
20.
Mem. Inst. Oswaldo Cruz ; 86(supl.2): 227-230, 1991. ilus, tab
Artigo em Inglês | LILACS | ID: lil-623975

RESUMO

Some informations about the sesquiterpene lactones isolated from Brazilian species of Vernonia are described, as well the results of tests developed with such compounds with respect to their anti-feedant, molluscicide, antimicrobial and analgesic properties.


Assuntos
Humanos , Animais , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/toxicidade , Sesquiterpenos/uso terapêutico , Sesquiterpenos/farmacologia , Vernonia/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/toxicidade , Antineoplásicos/farmacologia , Antineoplásicos/química , Flores/química , Linhagem Celular Tumoral , Etanol/química
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