150 likes | 375 Views
Effect of Amifostine On Mitochondrial Superoxide Dismutase Expression In INS-1 Beta Cells. Daniel Turner-Lloveras Dr. Michael Roe. Type 2 Diabetes Mellitus. Insulin Resistance Beta Cell Dysfunction Hyperglycemia Oxidative Stress (ROS) Beta Cell Degradation Beta Cell Death
E N D
Effect of Amifostine On Mitochondrial Superoxide Dismutase Expression In INS-1 Beta Cells Daniel Turner-Lloveras Dr. Michael Roe
Type 2 Diabetes Mellitus • Insulin Resistance • Beta Cell Dysfunction • Hyperglycemia • Oxidative Stress (ROS) • Beta Cell Degradation • Beta Cell Death • Complications of Diabetes • Blindness, Heart Disease, Kidney Problems, etc.
Endogenous Antioxidant Pathways normal [glucose] H2O MnSOD Glutathione Peroxidase O2- H2O2 Catalase H2O O2
Enhanced Endogenous Antioxidant Defense during hyperglycemia? HIGH [GLUCOSE] H2O H2O2 O2- MnSOD(?) Glutathione Peroxidase Catalase(?) (high mitochondrial metabolic activity) HO-- H2O O2 Oxidative Damage
Hypothesis • Amifostine induces upregulation of MnSOD (Sod2) via activation of NF-κβ
Amifostine • A phosphorothioate that is metabolized to the free thiol metabolite WR-1065. • Developed by military to protect soldiers during nuclear warfare. • The only drug approved by the FDA specifically as a radioprotector.
Amifostine ↑ NF-κβ ↑ MnSOD HIGH [GLUCOSE] H2O H2O2 O2- MnSOD(?) Glutathione Peroxidase Catalase(?) HO-- H2O O2 Oxidative Damage
METHODS • INS-1 Rat Insulinoma Cell Line • 40 µM WR-1065 • Real-Time/ Quantitative PCR (QPCR) • Western Immunoblotting 0 4 8 24 48 30 min Treatment Hours
QPCR DATA • Drug induced transient increase in MnSOD gene expression • No data for Glutathione Peroxidase and Catalase
Western Immunoblotting MnSOD MW 0 -- 4 + -- 8 + -- 24 + -- 48 + β-Actin -- = Control + = Treated with WR-1065
Western Blot DATA • Transient Increase in MnSOD levels in both drug treated and control
CONCLUSION • Amifostine upregulates sod2 (MnSOD) gene expression. • Effects on MnSOD protein levels are uncertain.
Future Directions • Refine Technique and repeat experiments • Investigate role of NF-κB • Mitochondrial function and insulin secretion • In vivo experiments with Fatty Zucker Diabetic Rats
Acknowledgements • Dr. Michael Roe • Dr. David Grdina • Dr. Jeff Murley • Luis Landa • Dr. Mark Harbeck • Kelly Kaihara • Dr. Kajorn Kitiphongspattana • Dr. Vernon Towle • Dr. Eugene Chang