Superoxide scavenging activity of erythromycin-iron complex.
We evaluated superoxide (O2-.) scavenging activity of erythromycin (EM) and of EM-iron complex by means of electron spin resonance spectroscopy, luminol-dependent chemiluminescence assay, and cytochrome c reduction assay. The EM-iron complex was produced by mixing EM with equal molar iron chloride and was stable in neutral buffer. The EM-iron complex reduced the amount of O2-. produced by xanthine oxidase/hypoxanthine without inhibiting the enzyme activity. It also reduced the amount of O2-. release from phorbor ester-stimulated human neutrophils and alveolar macrophages. EM alone showed few such effects. The scavenging activity of the complex was equal to that of L-ascorbic acid. These results in vitro suggest a possibility that the O2-.-scavenging effect of EM-iron complex contributes to the anti-inflammatory action of EM used in treating chronic inflammatory lung disease independent of its antimicrobial activity.
Muranaka
H
H
First Department of Internal Medicine, Kumamoto University School of Medicine, Japan.
Suga
M
M
Sato
K
K
Nakagawa
K
K
Akaike
T
T
Okamoto
T
T
Maeda
H
H
Ando
M
M
D004917:Erythromycin / Q000737:chemistry*; D016166:Free Radical Scavengers; D006801:Humans; D007501:Iron / Q000737:chemistry*; D016676:Macrophages, Alveolar / Q000378:metabolism; D009504:Neutrophils / Q000378:metabolism; D013481:Superoxides / Q000097:blood*
D016166:Free Radical Scavengers; D013481:Superoxides; D004917:Erythromycin; D007501:Iron