%0 Journal Article %A John Doukas %A Lisa Eide %A Karin Stebbins %A Adrienne Racanelli-Layton %A Luis Dellamary %A Michael Martin %A Elena Dneprovskaia %A Glenn Noronha %A Richard Soll %A Wolfgang Wrasidlo %A Lisette M. Acevedo %A David A. Cheresh %T Aerosolized Phosphoinositide 3-Kinase γ/δ Inhibitor TG100-115 [3-[2,4-Diamino-6-(3-hydroxyphenyl)pteridin-7-yl]phenol] as a Therapeutic Candidate for Asthma and Chronic Obstructive Pulmonary Disease %D 2009 %R 10.1124/jpet.108.144311 %J Journal of Pharmacology and Experimental Therapeutics %P 758-765 %V 328 %N 3 %X Phosphatidylinositol 3-kinases (PI3Ks) are key elements in the signaling cascades that lie downstream of many cellular receptors. In particular, PI3K δ and γ isoforms contribute to inflammatory cell recruitment and subsequent activation. For this reason, in a series of preclinical studies, we tested the potential of a recently developed small-molecule inhibitor of these two isoforms, TG100-115 [3-[2,4-diamino-6-(3-hydroxyphenyl)pteridin-7-yl]phenol], as a form of anti-inflammatory therapy for respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD). To determine pharmacokinetic profiles, aerosolized formulations of the drug were delivered to mice by a nose-only inhalation route, yielding high pulmonary TG100-115 levels with minimal systemic exposure. Safety assessments were favorable, with no clinical or histological changes noted after 21 days of daily dosing. In a murine asthma model, aerosolized TG100-115 markedly reduced the pulmonary eosinophilia and the concomitant interleukin-13 and mucin accumulation characteristic of this disease. As a functional benefit, interventional dosing schedules of this inhibitor also reduced airway hyper-responsiveness. To model the pulmonary neutrophilia characteristic of COPD, mice were exposed to either intranasal lipopolysaccharide or inhaled smoke. Aerosolized TG100-115 again inhibited these inflammatory patterns, most notably in the smoke model, where interventional therapy overcame the steroid-resistant nature of the pulmonary inflammation. In conclusion, aerosolized TG100-115 displays pharmacokinetic, safety, and biological activity profiles favorable for further development as a therapy for both asthma and COPD. Furthermore, these studies support the hypothesis that PI3K δ and γ are suitable molecular targets for these diseases. The American Society for Pharmacology and Experimental Therapeutics %U https://jpet.aspetjournals.org/content/jpet/328/3/758.full.pdf