| dc.description.abstract | Diabetic retinopathy (DR) is the leading cause of blindness in working age Americans. Chronic low-grade retinal inflammation is an essential contributor to the pathogenesis of DR, as it is known to drive many of the characteristic events of early DR. One of the earliest pathogenic hallmarks of DR is the development of basement membrane (BM) thickening in the retinal microvasculature. Recent studies suggest that BM thickening contributes to the DR pathological cascade; however, much remains to be elucidated about the exact mechanisms by which BM thickening develops and subsequently drives other pathogenic events in DR. In this dissertation, we sought to expand our understanding of the roles of both chronic inflammation and BM thickening in driving early DR pathogenesis. First, in Chapter III, we demonstrate the potential of nuclear factor of activated T-cell (NFAT) inhibition to mitigate retinal inflammation secondary to diabetes, including significant efficacy in attenuating IL-1β-induced Müller and endothelial cell inflammation, increased leukocyte adhesion, and vascular hyperpermeability. Second, in Chapter IV, we undertook a systematic analysis to understand how human retinal microvascular endothelial cells (hRMEC) and human retinal pericytes (hRP) change expression of key extracellular matrix (ECM) constituents when treated with diabetes-relevant stimuli designed to model the three major insults of the diabetic environment: hyperglycemia, dyslipidemia, and inflammation. TNFα and IL-1β caused the most potent and consistent changes in ECM expression in both hRMEC and hRP. We also demonstrated that cytokine-induced alterations in ECM composition alone cause both increased adhesion molecule expression by and increased leukocyte adhesion to naïve hRMEC. Finally, in Chapter V, we utilized quantitative mass spectrometry to establish the unique constituency of hRMEC-derived ECM and identify changes in hRMEC-derived ECM under diabetes-relevant inflammatory conditions. In summary, we have demonstrated that NFAT inhibition has strong therapeutic potential to mitigate diabetes-related retinal inflammation, that inflammation drives significant changes in retinal vascular ECM, that these changes in retinal vascular ECM promote pathogenic changes in leukocyte adhesion behavior, and that retinal pericytes are likely equal contributors to the development of vascular BM thickening. | |
