In-vitro Model System for Calcific Band Keratopathy and Inhibitory Effects of C60 Fullerene Derivatives
Barron, Andrew R.
Doctor of Philosophy
Calcific band keratopathy (CBK) is a degenerative condition resulting in the deposition of calcium salts in the superficial layers of the cornea and causing significant visual disturbance and pain of the affected eye. The amount of CBK precipitates recovered from the affected eye is very small rendering a great challenge in development of an effective and non-invasive treatment for this condition. This provides an impetus to study the possible chemical factors that may contribute to the development of CBK in an effort to develop a more efficient and un-intrusive treatment for this condition. To this end, we have developed an in-vitro model system resembling band keratopathy's chemical composition and morphology thus providing insight to the mechanism of formation and allowing for mass production of the material furthering the advances of therapeutic targeting CBK. Our study is the fIrst to demonstrate that low molecular silicon can assist in the formation of CBK. Given the predominance of calcium and presence of silicon in CBK material, we have investigated the effect of calcium and silicon chelators on our reference and synthetic samples. Our results reveals nitrilotris( methylene) phosphonic acid, citric acid, and fructose as promising choices for chelation therapy for band keratopathy. The unique structural, physical, and photo-, electro-chemical properties of buckminsterfullerne C60 and its derivatives have rendered them particularly interesting for the field of nanomedicine. Toward this end, we have synthesized and investigated a series of derivatized C60 fullerenes possessing amine and amino acid pendant groups as inhibitors of the zinc enzymes carbonic anhydrases (CAs) and the human immunodeficiency virus type I aspartic protease (HIV -1 PR). Computational studies were performed in order to shed light in understanding the inhibition mechanism of CAs by these derivatives. Our collaborative investigation reveals that the CA isoforms show diverse inhibition profiles with our fullerene derivatives. Both computational and experimental techniques confirmed anti HIV -1 PR inhibitory effects of our C60 derivatives. Additionally, we have synthesized a series of C60 fullerene-peptides in order to investigate their cellular uptake, interference in vitro with specific DNA binding and inhibition of neuroblastoma cell growth. Our in vitro cell studies show that these fullerene-peptides are capable of penetrating into cytoplasm of the JF neuroblastoma cells. Cell viability study was undertaken in order to examine the biological response of our fullerene peptides for neuroblastoma cell proliferation.