Transcript The effect of copper chelators on superoxide production

The effect of copper chelators on
Zn(-) Superoxide Dismutase
Lucy Brennan
Dr. Joe Beckman
Dr. Kari Trumbull
Amyotrophic Lateral Sclerosis
 Motor neuron disease characterized by
progressive paralysis
 10% of cases are familial
 Mutations in SOD account for up to 7% of
fALS
Superoxide dismutase
 (Cu2+ Zn)SOD+O2---> (Cu1+ Zn)SOD+O2
(Cu1+ Zn)SOD +O2-+2H+--> (Cu2+ Zn)SOD+H2O2
 Mutations linked to structural instability
 Zn(-)SOD has a toxic gain of function believed to
underlie fALS
 (Cu1+)SOD +O2--> (Cu2+)SOD+ 02-
Copper chelators
 Dimercaptrol (BAL)
 treatment for heavy
metal toxicity and
Wilson’s disease
 Sulfhydral complex
Goals
 Validation of WST assay
 To find a Cu-chelator that effectively
removes copper from SOD
 Modifying the Cu-chelator into a
potential drug for ALS
WST assay
Superoxide detection
 An assay including
potassium superoxide
and WST-1 was
performed
 Addition of KO2- was
added to the assay
 WST has been
reduced
Xanthine assay
 WST-1 + Xanthine
and Xanthine oxidase
 An increased
absorbance was
noted, indicating that
WST-1 is reacting with
superoxide
Addition of BAL with Zn(-)SOD
Implications
 Validation of WST assay
 Limitations
 Insight into activity of Zn(-)SOD
 Possible chelation therapy for ALS
 Viable test for such compounds
Acknowledgements
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HHMI
Kevin Ahern
Dr. Joe Beckman
Dr. Kari Trumbull