EVALUATING THE MECHANISMS OF UNCONJUGATED BILIRUBIN TOXICITY THROUGH ANALYSIS OF THE DISULFIDE PROTEOME
Date of Award
Master of Science
Dr. Jack R. Bend
Dr. Subrata Chakrabarti
Dr. Chandan Chakraborty
Unconjugated bilirubin (UCB), the end product of heme catabolism, is an important physiological antioxidant at nMolar concentrations, but becomes a pro-oxidant at pMolar concentrations by causing the release of reactive oxygen species (ROS) from mitochondria. We employed diagonal redox two-dimensional polyacrylamide gel electrophoresis (R2D-PAGE), to separate and identify specific proteins by mass spectrometry and determined the proteomic signature of the disulfide proteome in different subcellular fractions of Hepa lclc7 cells treated with pro-oxidant (50 pM) or antioxidant (70 nM) concentrations of UCB in Hepa lclc7 cells. Our results demonstrate that treating cells with pro-oxidant or antioxidant concentrations of UCB had a significant and different change on disulfide bonded proteins in the cytosol, with notable effects on peroxiredins (Prx). Pro-oxidant concentrations of UCB led to the irreversible oxidation of Prxl with no effect on Prx2, whereas antioxidant concentrations led to an enhanced reduction in Prx2 with no effect on Prxl.
Awaysheh, Abudi, "EVALUATING THE MECHANISMS OF UNCONJUGATED BILIRUBIN TOXICITY THROUGH ANALYSIS OF THE DISULFIDE PROTEOME" (2010). Digitized Theses. 3899.