The toxicity of Aspidosperma subincanum to MCF7 cells is related to modulation of oxidative status and proinflammatory pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Cancer is an inflammatory disease because carcinogenesis and tumor progression depend on intrinsic and extrinsic inflammatory pathways. Although species of the genus Aspidosperma are widely used to treat tumors, and there is ethnopharmacological evidence for traditional use of the species A. subincanum as an anti-inflammatory agent, its antineoplastic potential is unknown. AIM OF THE STUDY: To evaluate toxic effects of the indole alkaloid-rich fraction (IAF) of A. subincanum on the MCF7 cell line and identify some of the anti-inflammatory mechanisms involved. MATERIALS AND METHODS: Chromatographic analyses were performed by ultra-high-performance liquid chromatography with electrospray ionization mass spectrometry, and cytotoxic and antiproliferative effects of IAF were verified by MTT and clonogenic assays. Cell cycle alterations were analyzed by measuring DNA content, while propidium iodide and acridine orange staining was performed to determine the type of induced cell death. The expression of apoptosis markers and proteins involved in cell proliferation and survival pathways was analyzed by immunoblotting, RT-qPCR, and ELISAs. Interference with redox status was investigated using a DCFH-DA probe and by measuring catalase activity. RESULTS: Chromatographic analyses showed that IAF is a complex mixture containing indole alkaloids. IAF selectively exerted toxic and antiproliferative effects, elevating the Bax/Bcl-xL ratio and inducing apoptosis in MCF7 cells. IAF decreased intracellular reactive oxygen species levels and increased catalase activity, while reducing the IL-8 level and suppressing COX-2 expression. CONCLUSIONS: IAF induces apoptosis in MCF7 cells by suppressing COX-2 expression while reducing IL-8 levels and intracellular content of reactive oxygen species.

Occurrence of antibiotics and antibiotic resistant bacteria in subtropical urban rivers in Brazil.

The occurrence of antibiotics in the natural environment has been a growing issue and correlations between this presence and developing resistance bacteria are explored. The purpose of this study was to investigate the presence of antibiotics of different classes and associated resistant bacteria, in water samples taken from urban river waters in Curitiba, Brazil. A method for the quantification of antibiotics (azithromycin, amoxicillin, norfloxacin ciprofloxacin, doxycycline and sulfamethoxazole) was developed and validated using liquid chromatography coupled with mass spectrometry. To investigate and identify coliforms resistant to these antibiotics, we performed selective microbiological culturing techniques. We detected antibiotics in our water samples; concentrations ranged from 0.13 to 4.63 µg L-1, with the highest being amoxicillin at 4.63 µg L-1. In all water samples this study, antibiotic resistant bacteria were detected. Escherichia coli was resistant to amoxicillin, norfloxacin, ciprofloxacin, doxycycline and sulfamethoxazole. Strains producing ß-lactamase with extended spectrum (ESBL and AmpC) were also found in these isolates. Enterococcus spp. displayed resistance to norfloxacin and ciprofloxacin, and some isolates were resistant to vancomycin, gentamicin and streptomycin (complementary tests). No P. aeruginosa resistant strains were observed. It is possible these antibiotics came from domestic effluents and may be contributing to the spread of bacterial resistance.