The applicant is committed to developing a career as a successful physician-scientist and has created a career development plan described in this proposal that will allow him to do so. The central component of this five-year plan is the research project outlined below. In addition, the applicant will benefit from the mentorship of Dr. Marc Peters-Golden (primary) and Dr. Bruce Richardson (co-mentor), both accomplished senior professors with extensive and successful track records for mentoring. Formal coursework, seminars, and conference participation are included in this plan. This plan is further enhanced by the outstanding research and mentoring environment that exists at the University of Michigan. Idiopathic pulmonary fibrosis (IPF) is a devastating disease with limited effective therapies. Abnormal fibroproliferation is a key pathobiological hallmark. Prostaglandin (PG) E2 is a lipid mediator that potently inhibits fibroblasts, the main effector cell in fibrotic responses. The applicant has recently discovered that fibroblasts from some patients with IPF are resistant to PGE2 suppression, and that this is due to deficiency of the E prostanoid (EP) 2 receptor. This finding parallels observations made in the bleomycin mouse model of pulmonary fibrosis. What is unclear is how EP2 expression is lost in these cells. Epigenetic changes, which are covalent modifications to DMA and chromatin, are important in regulating gene expression, and are increasingly recognized to be important in disease. Preliminary data suggest that epigenetic mechanisms may be responsible for loss of EP2 expression and impaired PGE2 responsiveness in fibrotic fibroblasts. To test this hypothesis, we will study lung fibroblasts from cell lines, patients with DIP, and from mice treated with bleomycin.
Our Specific Aims will be to address the role of 1) DMA methylation and 2) histone deacetylation in regulating EP2 receptor expression and PGE2 responses in normal lung fibroblasts. We will then study how DMA methylation and/or histone deacetylation may be responsible for EP2 deficiency/PGE2 resistance in fibroblasts from 3) bleomycin-treated mice and 4) patients with IPF. The applicant will build upon his productive training experience by acquiring new scientific knowledge and research skills, particularly in the area of epigenetics, a field that has generated significant enthusiasm within the scientific community. Successful completion of the outlined studies will provide new insight into pathogenic mechanisms of pulmonary fibrosis and provide the applicant with the skills to achieve academic independence in an exciting and important research niche.
Idiopathic pulmonary fibrosis is a devastating lung disease with a poor prognosis and little effective therapy. The research proposed in this plan seeks to better understand the pathogenesis of pulmonary fibrosis which may lead to the development of better therapeutic strategies against this deadly disease.
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|Penke, Loka R K; Huang, Steven K; White, Eric S et al. (2014) Prostaglandin E2 inhibits ?-smooth muscle actin transcription during myofibroblast differentiation via distinct mechanisms of modulation of serum response factor and myocardin-related transcription factor-A. J Biol Chem 289:17151-62|
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|Okunishi, Katsuhide; Sisson, Thomas H; Huang, Steven K et al. (2011) Plasmin overcomes resistance to prostaglandin E2 in fibrotic lung fibroblasts by reorganizing protein kinase A signaling. J Biol Chem 286:32231-43|
|Huang, Steven K; Fisher, Aaron S; Scruggs, Anne M et al. (2010) Hypermethylation of PTGER2 confers prostaglandin E2 resistance in fibrotic fibroblasts from humans and mice. Am J Pathol 177:2245-55|
|Bauman, Kristy A; Wettlaufer, Scott H; Okunishi, Katsuhide et al. (2010) The antifibrotic effects of plasminogen activation occur via prostaglandin E2 synthesis in humans and mice. J Clin Invest 120:1950-60|