RESUMO
The present study reports the identification of two new staurosporine derivatives, 2-hydroxy-7-oxostaurosporine (1) and 3-hydroxy-7-oxostaurosporine (2), obtained from mid-polar fractions of an aqueous methanol extract of the tunicate Eudistoma vannamei, endemic to the northeast coast of Brazil. The mixture of 1 and 2 displayed IC50 values in the nM range and was up to 14 times more cytotoxic than staurosporine across a panel of tumor cell lines, as evaluated using the MTT assay.
Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Estaurosporina/análogos & derivados , Urocordados/química , Animais , Antineoplásicos/isolamento & purificação , Organismos Aquáticos/química , Brasil , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Células HL-60 , Humanos , Concentração Inibidora 50 , Células Jurkat , Células K562 , Espectroscopia de Ressonância Magnética/métodos , Estaurosporina/química , Estaurosporina/isolamento & purificação , Estaurosporina/farmacologiaRESUMO
The present study aimed to assess the sediment quality in a tropical estuary located in the northeast of Brazil under semi-arid conditions and multiple sources of contamination, using both toxicity bioassays and metal distribution. The metal distribution followed a concentration gradient decreasing one order of magnitude from the inner station toward the outer estuary, with amounts in the following order: Fe > Al > Zn > Cr > Pb > Cu. The index of geoaccumulation indicated a metal enrichment in the Ceará river sediment, mainly at inner sites, considered from moderately to strongly contaminated by Al, Cu, Cr and Zn. Sediment samples were considered toxic by means of whole sediment tests with copepods (reproduction) and amphipods (survival), and also elutriate fraction and sediment-water interface with sea urchin embryos (development). Acute and chronic toxicity did not exhibit a significant correlation with metals, emphasizing the influence of other contaminants mainly related to the pollution sources installed in the mid-estuary.