RESUMO
The present study investigated the possibility of apoptosis-inducing activity in human leukemia U-937 and THP-1 cells by the flavonoid morin. The treatments were evaluated by using the MTT and LDH assays; analysis of mitochondrial membrane potential (ΔΨm) was evaluated by flow cytometry, cell death by apoptosis was confirmed by fluorescence microscopy and by assessing the activity of caspases-3 and -6. The data indicated that the flavonoid morin has promoted a decrease in cell viability in a concentration-dependent way for both of the cancerous cell lines. An increase in the percentage of cell death caused by apoptosis was associated to a potential alteration in the mitochondrial membrane (ΔΨm) suggesting the involvement of cell death in intrinsic apoptotic pathways. Activation of caspases-3 and -6 confirmed the presence of apoptotic activity from morin. The results reinforce the antileukemic potential of flavonol morin.
Assuntos
Caspases , Flavonoides , Apoptose , Caspase 3 , Caspases/metabolismo , Linhagem Celular Tumoral , Flavonoides/farmacologia , Humanos , Potencial da Membrana MitocondrialRESUMO
Since 2009 a policy has been implemented in Brazil to establish the natural concentrations of potentially toxic substances in soil for each state. Historically a 'mining state', Minas Gerais established a Quality Reference Value for metal(loid)s for all of the soils in the state. To successfully establish these values it is important to study the spatial geochemical diversity for the state. In this context, the objectives of this work are: (1) to evaluate the natural concentrations of metal(loid)s in pristine Minas Gerais soils and (2) to interpret the spatial variability in concentration of these elements. The 0-20 cm layer of soils was sampled for 697 georeferenced sites including the main geological materials and soil groups. Soil properties were analyzed according to methodologies suitable for Brazilian soils. The concentration of metal(loid)s was determined by acid extraction according to EPA 3051A. Descriptive statistics, Pearson correlation and spatial variability analyses were performed. The dominance of acidic pH and low CEC values reflects the pervasive deep acid weathering. The variability of metal(loid) concentrations for soils of the state may be attributed to geological diversity and different pedogenesis. Correlation and spatial analysis indicated that the Fe concentration is strongly associated with metal(loid) concentrations in topsoil. According to the spatial geochemical diversity of the state, a k-means cluster analysis was performed which identified four clusters. A significant difference in the mean values of metal(loid) concentrations between the clusters confirmed that the single Quality Reference Value established does not represent the geochemical diversity of soils in Minas Gerais.