Icariin Attenuates Carbon Black-Induced Pulmonary Inflammatory Response And Oxidative Stress In Mice

Particulate matter (PM) exposure is closely associated with mortality and morbidity related to pulmonary and cardiovascular diseases. Icariin has been shown to play a beneficial role in pulmonary and cardiovascular diseases. Here, we assessed the protective effect of icariin on mice exposed to ultrafine carbon black (CB), one of the main components in PM. Mice were subjected to a single intratracheal instillation of CB (50 mu g), followed by icariin treatment. Twenty-four hours post-exposure, lung tissues and the bronchial alveolar lavage fluid (BALF) were collected for subsequent histopathological and molecular analyses. Instillation of CB caused significant increase in BAL neutrophils, macrophages, and lymphocytes, with concomitant elevation of total protein levels, lactic dehydrogenase (LDH) release, and proinflammatory mediators (TNF-alpha, IL-6, and IL-1 beta). Furthermore, CB increased the MDA content while decreased the activity of antioxidant superoxide dismutase (SOD) in lung tissues. Compared to CB group, icariin treatment significantly reversed these elevations induced by CB and increased the activity of SOD in lung tissues. Taken together, our results indicate that icariin exerts protective effects on CB-induced pulmonary inflammation and cytotoxicity, which might be due to its anti-inflammatory and anti-oxidant properties.