Comparing the protective effects of ciprofloxacin, moxifloxacin and levofloxacin in mice with lipopolysaccharide-induced acute lung injuries

Background and objective: Ciprofloxacin, moxifloxacin and levofloxacin are recognized immunomodulators. Their effects in acute lung injuries have not been tested. This study compared the immunoprotective effects of these agents in mice with lung injuries induced by LPS by measuring the cytokine profiles in the injured lung and the associated mortality. Methods: The development of lung injury and mortality was compared in mice pretreated with either ciprofloxacin, levofloxacin, moxifloxacin or saline (control group) after the intratracheal administration of LPS. BALF and serum were collected at 1, 3 and 6 h to measure the concentrations of tumour necrosis factor-α (TNF-α), IL-1β, IL-6, IL-10 and macrophage inflammatory protein-2 (MIP-2) using enzyme-linked immunoassay. Results: Levels of TNF-α, IL-1β and MIP-2 in the BAL of the ciprofloxacin group were significantly lower compared with those of controls (all P < 0.0083) at 3 and 6 h after LPS challenge. There were no significant differences in the levels of these cytokines in the moxifloxacin and levofloxacin groups compared with controls. Overall, the 96-h survival for the mice pretreated with ciprofloxacin, but not for those pretreated with moxifloxacin or levofloxacin, was significantly greater than that of the control animals (P = 0.019). Conclusions: In the setting of LPS-induced lung injuries, ciprofloxacin appears to provide better anti-inflammatory properties and survival benefits than the other fluoroquinolones tested.