Pulmonary effects and disposition of luteolin and Artemisia afra extracts in isolated perfused lungs

Abstract

ETHNOPHARMACOLOGICAL RELEVANCE: Artemisia afra (Asteraceae) is a traditional medicinal plant frequently used in steam inhalation form to treat respiratory conditions. AIM OF THE STUDY: Quantify luteolin content in Artemisia afra dried crude and aqueous extract. Evaluate the pulmonary effects of Artemisia afra steam inhalation, nebulized Artemisia afra extract and luteolin in isolated perfused lungs (IPL). Evaluate the pulmonary disposition of intravenously administered luteolin. MATERIALS AND METHODS: HPLC was used to quantify luteolin in Artemisia afra extracts. A modified version of the IPL was used to determine the effects of Artemisia afra steam inhalation, nebulized luteolin, and nebulized aqueous leaf extract on lung function, as well as the pulmonary disposition of IV luteolin. RESULTS: Artemisia afra extract contained significantly higher luteolin levels than the crude dried leaves. Inhaled Artemisia afra steam, and nebulized luteolin, and Artemisia afra extract and IV luteolin produced significant dose-dependent improvements in lung function, with nebulized Artemisia afra producing the greatest improvements. Nebulisation with Artemisia afra extract yielded higher quantities of luteolin than luteolin nebulisation. CONCLUSION: Results verify the traditional use of inhalation of Artemisia afra steam, although nebulized luteolin and aqueous extract are better alternatives. Luteolin significantly contributes to the broncho-dilatory effects of Artemisia afra.