Suppression of severe airway inflammation with non-toxic dietary nutrients in histamine-challenged guinea pigs: A comparison with Ibuprofen

Abstract

We hypothesize that selected combinations of nutrients commonly encountered in the human diet, suppress asthma-associated airway inflammation more effectively than currently available anti-inflammatory medications. Here we demonstrate that biflavones and terpenes, distributed widely in human diet (in this case derived from Ginkgo biloba) synergize with the carotenoid antioxidant astaxanthin and vitamin C to suppress asthma-associated inflammation in a guinea pig model. Male Hartley guinea pigs treated with 10-1000 mg/kg Ibuprophen, or: EGb761 (0-100 mg/kg), astaxanthin (0-200 mg/kg), vitamin C (0-400 mg/kg), or combinations thereof, were ovalbumin sensitized, then challenged with ovalbumin aerosol to induce asthma. Each animal was evaluated for inflammation-associated indicators. Differential cell counts were performed on bronchoalveolar fluid using standard morphologic criteria to classify cells as eosinophils, neutrophils, or macrophages. Cyclic nucleotide (cAMP and cGMP) content in lung tissue was measured using radioimmunoassay. Each disease indicator was significantly altered to a greater degree by combinations of drugs, than by components acting independently, or by Ibuprophen. Optimal combinations were identified that included astaxanthin (10 mg/kg), vitamin C (200 mg/kg), and EGb761 (10 mg/kg), resulting in counts of eosinophils and neutrophils each 1.6-fold lower; macrophages 1.8-fold lower, cAMP 1.4-fold higher; and cGMP 2.04-fold higher than levels in untreated animals (p