Pulmonary inflammatory diseases linked to oxidant stress in lung tissues represent a major health concern in the U.S. These diseases include allergic asthma, chronic obstructive pulmonary disease, viral and bacterial infections, and related sepsis-induced acute lung injury. Evidence indicates that antioxidant defenses in the tissues play a pivotal role in reducing pulmonary inflammation and that enhancement of these protective pathways can lead to a reduction of tissue damage and morbidity. Emerging evidence has identified a central role for the transcription factor, Nrf2, in orchestrating the induction of a global network of tissue-protective antioxidant enzymes in response to oxidant-related stimuli. Much attention is being focused on means by which to stimulate activation of Nrf2 for both preventive and interventive therapies. Our preliminary studies have demonstrated that a constituent of a natural oil induces marked activation of Nrf2 and subsequent stimulation of its down-stream antioxidant gene targets. The Objectives of the Phase I research are to test the effectiveness and safety of the oil containing the active constituent in order to determine its potential for continued development in Phase II R&D as a therapeutic agent. Phase I Specific Aims are to: (1) Identify the component oil of the previously-tested oil mixture in which the primary Nrf2-stimulating activity resides. This will be achieved using cells stably transfected with an Nrf2 reporter construct followed by verification of antioxidant gene and protein expression in wild-type cells. (2) Determine the pharmacokinetics and Nrf2-selectivity of the active oil. The time-course of expression and efficacy of stimulation of antioxidant and cytotoxicity marker genes relative to known Nrf2 chemical activators will be examined. Nrf2 signaling will be assessed by nuclear protein accumulation and DNA binding (EMSA) and the absence of activity in Nrf2 -/- cells. Microarray analysis will identify the presence of concurrently-activated pathways. (3) Assess the effectiveness of the active constituent in reducing markers of inflammation and tissue damage in mouse models of allergic asthma and endotoxin- induced acute lung injury. Markers will include histopathologic measures and the expression of genes and proteins associated with the oxidant-related inflammatory pathology of these models. These studies will be carried out using cell culture and animal model systems and methodologies currently in use by the investigators. The activities of Phase I are expected to provide the scientific basis for further isolation and development of the active constituent present in the natural oil. It is anticipated that the outcome of Phase I and II research and development will be the identification of a molecule that will be attractive as a commercial product ready for development as a therapeutic agent.
Over 35 million Americans live with acute and chronic lung diseases whose pathology is linked to inflammation. Antioxidants synthesized in lung tissues are known to offer protection against pathologic processes associated with many of these diseases. The goal of this project is to isolate and test the effectiveness of an agent found in an essential oil that has been demonstrated to activate broad synthesis of protective antioxidants in the lung.
| Gao, Meixia; Singh, Anju; Macri, Kristin et al. (2011) Antioxidant components of naturally-occurring oils exhibit marked anti-inflammatory activity in epithelial cells of the human upper respiratory system. Respir Res 12:92 |
