Evidence for astrocytosis in ALS demonstrated by [11C](L)-deprenyl-D2 PET

Objective: To use deuterium-substituted [C-11](L)-deprenyl PET to depict astrocytosis in vivo in patients with amyotrophic lateral sclerosis (ALS). Background: In human brain, the enzyme MAO-B is primarily located in astrocytes. L-deprenyl binds to MAO-B and autoradiography with H-3-L-deprenyl has been used to map astrocytosis in vitro, Motor neuron loss in ALS is accompanied by astrocytosis and astrocytes may play an active role in the neurodegenerative process. Deuterium-substituted [C-11](L)-deprenyl PET provides an opportunity to localize astrocytosis in vivo in the brain of patients with ALS. Methods: Deuterium-substituted [C-11](L)-deprenyl PET was performed in seven patients with ALS and seven healthy control subjects. Results: Increased uptake rate Of [C-11](L)-deprenyl was demonstrated in ALS in pons and white matter. Conclusion: This Study provides evidence that astrocytosis may be detected in vivo in ALS by the use of deuterium-substituted [C-11](L)deprenyl PET though further studies are needed to determine whether deuterium-substituted [C-11](L)-deprenyl binding tracks disease progression and reflects astrocytosis. (c) 2007 Elsevier B.V. All rights reserved.