Anti-inflammatory effects of tilmicosin in a noninfectious mouse model of allergic asthma.

Tilmicosin, a semi-synthetic tylosin-derived macrolide antibiotic commonly used by veterinarians, has been shown to possess anti-inflammatory activity. However, possible use in asthma treatment has not yet been studied. In this study, we investigated the anti-inflammatory properties of tilmicosin using a murine asthma model. BALB/c mice were sensitized and challenged by intraperitoneal (i.p.) or nasal administration of ovalbumin. Tilmicosin (10 and 20 mg/kg) treatment resulted in a marked reduction in the presence of several types of immune cells and cytokines in the bronchoalveolar lavage fluids of mice. Levels of ovalbumin-specific Immunoglobulin E (IgE) were significantly decreased following treatment with tilmicosin (10 and 20 mg/kg). Histological studies using H&E (haematoxylin and eosin) and AB-PAS (alcian blue-periodic acid-Schiff) staining demonstrated that tilmicosin substantially inhibited both ovalbumin-induced inflammatory cells in lung tissues and goblet cell hyperplasia in the airway. These findings provided new insight into the immunopharmacological role of tilmicosin in terms of its effects in a murine model of asthma.