Characterization and Rapamycin Treatment Of Laryngotracheal Stenosis, In Vitro and In Vivo

Laryngotracheal Stenosis;rapamycin;trachea;Warburg effect;metabolism;not listed

Ma, Garret LiElisseeff, Jennifer H. ;

Johns Hopkins University

关键词: Laryngotracheal Stenosis;    rapamycin;    trachea;    Warburg effect;    metabolism;    not listed;   

Others  :  https://jscholarship.library.jhu.edu/bitstream/handle/1774.2/39247/MA-THESIS-2015.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: JOHNS HOPKINS DSpace Repository

【 摘 要 】

Laryngotracheal stenosis (LTS) is an unpredictable, dynamic fibrosis which results in pathologic tissue buildup in the larynx and trachea resulting in airway narrowing. LTS can be caused by prolonged intubation, local trauma, autoimmune disease, radiation exposure, or idiopathic reasons. In many cases, LTS causes significant morbidity by limiting one’s ability to speak, swallow and breathe, and may even cause mortality; however to date, there is no definite treatment to cure LTS. Defining the cellular metabolism and function of normal and LTS-derived laryngotracheal fibroblasts are unclear. Biopsies were obtained from eight patients undergoing operative procedures for LTS and biopsies were taken from both ;;normal” and ;;scar” segments of their trachea. Fibroblast and cancer lines were analyzed in vitro. Scar fibroblasts demonstrated increased proliferation rates, larger cellular area and increased collagen-1 expression compared to normal. Metabolically, scar fibroblasts reveal lower levels of oxidative phosphorylation and a higher ECAR/OCR ratio. Through a comparative analysis, scar fibroblasts exhibit a greater reliance on aerobic glycolysis. Scar fibroblasts proliferate considerably more than normal cells. Through a comparative analysis, we were able to determine that scar fibroblasts exhibit many of the characteristics of the Warburg effect. We believe that this discovery may open promising opportunities to exploit this phenomenon and prevent the proliferation of LTS in patients.Rapamycin was evaluated as a method to suppress proliferation and metabolism of scar fibroblasts in vitro. Rapamycin demonstrated an anti-fibrotic effect by reducing the proliferation, metabolism, and collagen deposition of human LTS fibroblast in vitro. The bioenergetic effects of rapamycin demonstrated a significant decrease in oxidative phosphorylation of LTS fibroblasts, suggesting a potential mechanism for the reduction of proliferation and differentiation. Rapamycin’s anti-fibrotic effects suggest a promising adjuvant therapy for the treatment of laryngotracheal stenosis. In addition, rapamycin when administered systemically in vivo when compared to PBS and dexamethasone, demonstrated a decrease in lamina propria thickness, a sign of decreased LTS. We believe that this one day could be translated to human clinical studies in order to provide a definitive treatment to a disease that currently has no effective therapy.