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1.
Oncol Rep ; 22(4): 845-52, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19724864

RESUMO

Hypericum perforatum (St. John's wort) is well-established for its antidepressant activity throughout the world and also various other species within this genus are used in different folk medicines. Hyperforin of St. John's wort inhibited growth of cancer cell lines and the use of hypericin (another compound of H. perforatum) in cancer photodynamic therapy is proposed. Therefore, we investigated the anti-cancer properties of H. adenotrichum Spach (Guttiferae), an endemic species in Turkey called 'kantaron', which is used for wound healing and antiseptic effects. Freeze-dried plant was extracted with petroleum ether, dichloromethane, ethyl acetate, and methanol and the bioactivity of these extracts was analysed by proliferation assay, cell death determination, by investigating protein expression profiles specific for cell cycle arrest and apoptosis as well as composition by HPLC. The strongest anti-proliferative activity was determined for the petroleum ether extract with an IpC50 of approximately 5.8 microg/ml medium (referring to 1 mg dried plant) which correlated with cyclin D1 suppression and p21 induction. This extract also induced phosphorylation of H2AX, and activated caspase-3 followed by signature-type cleavage of PARP resulting in approximately 50% apoptosis at 23.2 microg/ml after 24 h of treatment. Neither hyperforin, hypericin, or amentoflavone contributed to these properties. To the best of our knowledge, we report for the first time that the endemic plant H. adenotrichum Spach exhibits potent p53-independent anti-neoplastic properties due to yet unexplored Hypericum constituents.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Hypericum , Leucemia/tratamento farmacológico , Fitoterapia/métodos , Extratos Vegetais/farmacologia , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Humanos , Hypericum/química , Técnicas In Vitro , Turquia
2.
Int J Oncol ; 35(4): 881-91, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19724926

RESUMO

More than 60% of conventional drugs are derived from natural compounds, some of the most effective pharmaceuticals (e.g. aspirin, quinine and various antibiotics) originate from plants or microbes, and large numbers of potentially valuable natural substances remain to be discovered. Plants with considerable medicinal potential include members of the genus Acalypha. Notably, extracts of A. platyphilla, A. fruticosa, A. siamensis, A. guatemalensis and A. wilkesiana have been recently shown to have antioxidant, antimicrobial and cytotoxic effects. In the study presented here we investigated the anti-inflammatory, anti-proliferative and pro-apoptotic activities of A. alopecuroidea, which is endemic in parts of Central America and is traditionally used by the Mopan- and Itza-Maya in the form of decoctions to treat skin conditions, and as a tea to treat stomach and urinary complaints. We demonstrate here that extracts of A. alopecuroidea can inhibit TNFalpha-induced E-selectin production, providing a mechanistic validation of its traditional use against inflammatory diseases. Furthermore, a fraction of A. alopecuroidea root extracts purified by solid phase extraction and separated by HPLC displayed strong cell cycle inhibitory activity by down-regulating and inactivating two proto-oncogenes (cyclin D1 and Cdc25A), and simultaneously inducing cyclin A, thereby disturbing orchestrated cell cycle arrest, and thus (presumably) triggering caspase 3-dependent apoptosis. The results of this study indicate that there are high prospects for purifying an active principle from A. alopecuroidea for further in vivo and preclinical studies.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Euphorbiaceae , Leucemia Promielocítica Aguda/metabolismo , Anti-Inflamatórios/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quinase do Ponto de Checagem 2 , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Ciclina A/metabolismo , Ciclina D1/metabolismo , Relação Dose-Resposta a Droga , Selectina E/metabolismo , Células Endoteliais/imunologia , Euphorbiaceae/química , Feminino , Células HL-60 , Humanos , Inflorescência , Leucemia Promielocítica Aguda/patologia , Mutação , Folhas de Planta , Brotos de Planta , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Tempo , Transfecção , Fator de Necrose Tumoral alfa/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Fosfatases cdc25/metabolismo
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