RESUMO
A set of 8-methylene-, 8-methyl-, and 8-methyl-9-dihydro-oleandomycin derivatives having different combinations of stereochemistries at positions C-8 and/or C-9 have been prepared in a chemoselective and stereoselective manner and tested in vitro for antibacterial activity and inhibition of IL-6 production. Configurations of the stereocenters at C-8 and C-9 were determined using 2D NMR techniques. We have shown that change of stereochemistry at these positions can exert a major influence on antibacterial activity as well as IL-6 inhibition, providing novel macrolide derivatives with diminished antibacterial and potent anti-inflammatory activity. In addition, the anti-inflammatory activity observed in vitro was confirmed in an in vivo model of lipopolysaccharide-induced inflammation.
Assuntos
Antibacterianos/química , Anti-Inflamatórios/química , Oleandomicina/análogos & derivados , Animais , Antibacterianos/síntese química , Antibacterianos/farmacologia , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/farmacologia , Linhagem Celular , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Interleucina-6/metabolismo , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Neutrófilos/efeitos dos fármacos , Oleandomicina/síntese química , Oleandomicina/farmacologia , Baço/citologia , Baço/efeitos dos fármacos , EstereoisomerismoRESUMO
The full-thickness wound in the genetically diabetic (db/db) mouse is a commonly used model of impaired wound healing. We investigated delayed healing of non-occluded, excisional, full-thickness, dermal wounds in db/db mice in comparison to their normal littermate controls and refined methods for monitoring skin wound re-epithelialization, contraction, granulation tissue formation, and inflammation. We have confirmed with a computer-assisted planimetry method the results of previous studies showing that healing of non-occluded full excision wounds in db/db mice does not occur by contraction as much as in healthy mice. In addition, we have developed separate histological methods for the assessment of re-epithelialization, contraction, granulation tissue (mature, immature, fibrosis), and inflammation (lipogranulomas, secondary, nonspecific). Using a new approach to histological assessment, we have shown that wound closure in db/db mice is delayed owing to: (1) delayed granulation tissue maturation; (2) ''laced,'' widely distributed granulation tissue around fat lobules; and (3) obstruction by lipogranulomas, whereas the rate of re-epithelialization seems to be the same as in C57Bl/6 mice. This methodology should permit a more precise differentiation of effects of novel therapeutic agents on the wound healing process in db/db mice.
Assuntos
Diabetes Mellitus/patologia , Diabetes Mellitus/fisiopatologia , Pele/lesões , Cicatrização/fisiologia , Ferimentos Penetrantes/patologia , Animais , Feminino , Fibrose/patologia , Tecido de Granulação/patologia , Inflamação/patologia , Camundongos , Camundongos Endogâmicos C57BL , Pele/patologia , Ferimentos Penetrantes/etiologiaAssuntos
Anti-Inflamatórios/farmacologia , Claritromicina , Infecções por Escherichia coli , Lipopolissacarídeos/administração & dosagem , Choque Séptico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Anti-Inflamatórios/uso terapêutico , Claritromicina/farmacologia , Claritromicina/uso terapêutico , Modelos Animais de Doenças , Escherichia coli/metabolismo , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/mortalidade , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Choque Séptico/tratamento farmacológico , Choque Séptico/mortalidade , Resultado do TratamentoRESUMO
Macrolide antibiotics, including azithromycin, also possess anti-inflammatory properties. However, the molecular mechanism(s) of activity as well as the target cells for their action have not been unambiguously identified as yet. In this study, the effects of azithromycin on lipopolysaccharide (LPS)-induced pulmonary neutrophilia were investigated in mice. Using immunohistochemistry, mRNA and specific protein assays, we confirmed that azithromycin ameliorates LPS-induced pulmonary neutrophilia by inhibiting interleukin-1ß (IL-1ß) expression and production selectively in alveolar macrophages as well as in LPS-stimulated J774.2 macrophage-derived cells in vitro. Inhibition by azithromycin of neutrophilia and IL-1ß was accompanied by prevention of nuclear expression of activator protein-1 (AP-1) in both alveolar macrophages and J774.2 cells. The macrolide did not alter nuclear factor kappa B (NF-κB) or extracellular signal-regulated kinase 1/2 (ERK1/2) expression, activation or localization in LPS-stimulated lungs or in J774.2 cells. In conclusion, we have shown that inhibition of LPS-induced pulmonary neutrophilia and IL-1ß concentrations in lung tissue following azithromycin treatment is mediated through effects on alveolar macrophages. In addition, we have shown for the first time, in an in vivo model, that azithromycin inhibits AP-1 activation in alveolar macrophages, an action confirmed on J774.2 cells in vitro.