No abstract

Recently, there has been increasing evidence on the use of macrolide antibiotic in treatment of chronic inflammatory disease through mechanisms of distinct from their antibacterial activity. The key desired effect lies somewhere between these two therapeutic potentials and has not been identified yet. The aim of the present study was to evaluate the anti-inflammatory activity of azithromycin in formaldehyde induced arthritis and carrageenan induced air pouch in albino rats incomparable to meloxicam. Results of Formaldehyde induced arthritis revealed that pre-treatment of animals with either azithromycin (10,20,40) mg/kg or meloxicam (4mg/kg) I.P with single daily dose 1 hour before formaldehyde for 15 days produce significant reduction in Paw weight (9) (p<0.05), the percentage inhibition was 32.76%, 34.3%, 40.1% and 29.3% respectively. Histopathological study showed that Formaldehyde produced marked inflammatory cell infiltration, congestion of blood vessels and soft tissue edema which were attenuated by azithromycin in dose dependent manner. The radiological study revealed that azithromycin attenuate soft tissue oedema, periarticular bone resorption, narrowing of joint spaces and joint deformities induced by formaldehyde. This effect was marked with 40mg/kg azithromycin pre-treatment. In carrageenan induced air pouch, results demonstrate that group of animals pre-treated with azithromycin (10, 20 and 40 mg/kg/day) or meloxicam (4mg/kg) for 6 days significantly attenuated the mean increase in TLC in air pouch exudate with percentage of inhibition by 59.3%, 6.3%, 77.4% and 67.7% respectively. In conclusion, the present work showed that azithromycin has anti-inflammatory activity in the models tested and suggests that it can exert therapeutics effects independent of its anti-bacterial activity. Also, the anti-inflammatory effect of azithromycin 40mg/kg was potent and even comparable to that of meloxicam 4mg/kg.