50 research outputs found

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    Honeys are described possessing different properties including antimicrobial. Many studies have presented this activity of honeys produced by Apis mellifera bees, however studies including activities of stingless bees honeys are scarce. The aim of this study was to compare the antimicrobial activity of honeys collected in the Amazonas State from Melipona compressipes, Melipona seminigra and Apis mellifera against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Chromobacterium violaceum, and Candida albicans. Minimum inhibitory concentrations were determined using the agar dilution method with Müller-Hinton agar (for bacteria) or Saboraud agar (for yeast). Staphylococcus aureus and E. faecalis were inhibited by all honeys at concentrations below 12%, while E. coli and C. violaceum were inhibited by stingless bee honeys at concentrations between 10 and 20%. A. mellifera honey inhibited E. coli at a concentration of 7% and Candida violaceum at 0.7%. C. albicans were inhibited only with honey concentrations between 30 and 40%. All examined honey had antimicrobial activity against the tested pathogens, thus serving as potential antimicrobial agents for several therapeutic approaches.Méis são descritos possuindo diferentes propriedades, incluindo a antimicrobiana. Muitos estudos têm apresentado essa atividade de méis produzidos por abelhas Apis mellifera, no entanto estudos incluindo atividades de méis de abelhas sem ferrão são escassos. O objetivo deste estudo foi comparar a atividade antimicrobiana de méis de Melipona compressipes, Melipona seminigra e A. mellifera, coletados no Estado do Amazonas, contra Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Chromobacterium violaceum, e Candida albicans. As concentrações inibitórias mínimas foram determinadas usando o método de diluição em ágar, com ágar Muller-Hinton (para bactérias) ou ágar Sabouraud (para a levedura). S. aureus e E. faecalis foram inibidos por todos os méis em concentrações inferiores a 12%, enquanto E. coli e C. violaceum foram inibidos por méis de abelhas sem ferrão em altas concentrações entre 10 e 20%. A. mellifera inibiu E. coli na concentração de 7% e C. violaceum em baixa concentração (0,7%). C. albicans foi inibida apenas em concentrações entre 30 e 40% dos méis. Assim, todas as variedades de mel testadas apresentaram atividade antimicrobiana sobre os patógenos testados, servindo assim como agente antimicrobiano potencial para diversas abordagens terapêuticas

    Design, synthesis, and biological evaluation of new thalidomide–donepezil hybrids as neuroprotective agents targeting cholinesterases and neuroinflammation

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    A new series of eight multifunctional thalidomide–donepezil hybrids were synthesized based on the multi target-directed ligand strategy and evaluated as potential neuroprotective, cholinesterase inhibitors and anti neuroinflammatory agents against neurodegenerative diseases. A molecular hybridization approach was used for structural design by combining the N-benzylpiperidine pharmacophore of donepezil and the isoindoline 1,3-dione fragment from the thalidomide structure. The most promising compound, PQM-189 (3g), showed good AChE inhibitory activity with an IC50 value of 3.15 μM, which was predicted by docking studies as interacting with the enzyme in the same orientation observed in the AChE–donepezil complex and a similar profile of interaction. Additionally, compound 3g significantly decreased iNOS and IL-1β levels by 43% and 39%, respectively, after 24 h of incubation with lipopolysaccharide. In vivo data confirmed the ability of 3g to prevent locomotor impairment and changes in feeding behavior elicited by lipopolysaccharide. Moreover, the PAMPA assay evidenced adequate blood–brain barrier and gastrointestinal tract permeabilities with an Fa value of 69.8%. Altogether, these biological data suggest that compound 3g can treat the inflammatory process and oxidative stress resulting from the overexpression of iNOS and therefore the increase in reactive nitrogen species, and regulate the release of pro-inflammatory cytokines such as IL-1β. In this regard, compound PQM-189 (3g) was revealed to be a promising neuroprotective and anti-neuroinflammatory agent with an innovative thalidomide–donepezil-based hybrid molecular architectur
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