ABSTRACT
Flavonoids are polyphenols that are ubiquitous in plants and frequently consumed in the diet. They are suggested to have many beneficial actions on human health, including anti-inflammatory activity. Their properties have been studied in a number of cell types, but little is known about their effects on neutrophil biology. Consequently, we selected 25 flavonoids with different structural features to evaluate their in vitro inhibition of rat polymorphonuclear neutrophil (PMN) chemotaxis, employing a modified Boyden chamber. Migratory activity was measured towards a chemotactic stimulant, formyl-Met-Leu-Phe or lipopolysaccharide. Furthermore, the cytotoxic effect of flavonoids on PMNs was determined by the release of cytosolic lactate dehydrogenase (LDH). Ten flavonoids significantly retarded the migration of PMNs with at least one of the concentrations tested in a range between 0.625 and 100 µM; the best antichemotactic agents were flavone, flavonol, quercetin and rutin. None of the flavanones evaluated presented any significant inhibition of migration in this assay. Our findings indicated that non-hydroxylated flavones possess a better antichemotactic activity when compared to flavones with hydroxy groups. The presence of a sugar moiety in rutin did not produce any increase in this effect, when compared to the respective aglycone analogue. Finally, none of the flavonoids exhibited cell toxicity and for many of these flavonoids this is the first report of the inhibition of PMN chemotaxis.
Subject(s)
Chemotaxis, Leukocyte/drug effects , Flavonoids/pharmacology , Neutrophils/drug effects , Plant Extracts/pharmacology , Achyrocline/chemistry , Animals , Anti-Inflammatory Agents/pharmacology , Cell Migration Inhibition/drug effects , Chemotactic Factors/antagonists & inhibitors , Chemotactic Factors/pharmacology , Cytotoxins/pharmacology , Flavonoids/chemistry , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , N-Formylmethionine Leucyl-Phenylalanine/antagonists & inhibitors , N-Formylmethionine Leucyl-Phenylalanine/pharmacology , Neutrophils/immunology , Plant Extracts/chemistry , RatsABSTRACT
O objeto de estudo foi apurar diferenças entre o comportamento de farmacêuticos e balconistas quando um paciente recorre a estes estabelecimentos buscando informaçöes sobre o uso de medicamentos. O levantamento de dados foi realizado por um estudante que chegava às farmácias relatando um caso de diarréia e solicitando orientaçäo. 95% dos farmacêuticos e todos os balconistas prescreveram medicamentos sem indicar a procura de orientaçäo médica. As perguntas realizadas pelos mesmos, bem como as classes terapêuticas "prescritas" säo mostradas. Essencialmente nenhuma diferença foi encontrada entre o comportamento de farmacêuticos e balconistas
