Investigation of the anti-inflammatory and membrane-stabilizing potential of spiramycin in vitro

The effects of the 16-member macrolide spiramycin (2.5-80 mg/L) and the 14- member agent clarithromycin on the production of superoxide by activated hu man neutrophils were compared in vitro and related to membrane-stabilizing activity. Superoxide production was measured by lucigenin-enhanced chemilum inescence with N-formyl-L-methionyl-L-leucyl-L-phenylalanine (1 mu M) as th e stimulus, and membrane-stabilizing activity was measured by a haemolytic procedure. Clarithromycin, but not spiramycin, caused dose-related inhibiti on of superoxide production by activated neutrophils and also protected ery throcytes against haemolysis, while spiramycin possessed only weak membrane -stabilizing activity. These observations under-score the apparent associat ion between the anti-inflammatory and membrane-stabilizing properties of ma crolides.