alpha 7 Nicotinic Receptor Agonists Reduce Levodopa-Induced Dyskinesias With Severe Nigrostriatal Damage

作者：Zhang Danhui; McGregor Matthew; Bordia Tanuja; Perez Xiomara A; McIntosh J Michael; Decker Michael W; Quik Maryka^*

来源：Movement Disorders, 2015, 30(14): 1901-1911.

DOI：10.1002/mds.26453

• dyskinesia
• levodopa
• ABT-126
• nicotinic
• Parkinson's disease

Background: ABT-126 is a novel, safe, and well-tolerated alpha 7 nicotinic receptor agonist in a Phase 2 Alzheimer's disease study. We tested the antidyskinetic effect of ABT-126 in 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine-treated squirrel monkeys with moderate and more severe nigrostriatal damage.
Methods: Monkeys (n = 21, set 1) were lesioned with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine 1-2x. When parkinsonian, they were gavaged with levodopa (10 mg/kg)/carbidopa (2.5 mg/kg) twice daily and dyskinesias rated. They were then given nicotine in drinking water (n = 5), or treated with vehicle (n = 6) or ABT-126 (n = 10) twice daily orally 30 min before levodopa. Set 1 was then re-lesioned 1 to 2 times for a total of 3 to 4 1-methyl- 4-phenyl-1,2,3,6-tetrahydropyridine injections. The antidyskinetic effect of ABT-126, nicotine, and the beta 2* nicotinic receptor agonist ABT-894 was re-assessed. Another group of monkeys (n = 23, set 2) were lesioned with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine only 1x to 2x. They were treated with levodopa/carbidopa, administered the alpha 7 agonist ABT-107 (n = 6), ABT-894 (n = 6), nicotine (n = 5), or vehicle (n = 6) and dyskinesias evaluated. All monkeys were euthanized and the dopamine transporter measured.
Results: With moderate nigrostriatal damage (1-methyl- 4-phenyl-1,2,3,6-tetrahydropyridine 1 x -2x), ABT-126 dose-dependently decreased dyskinesias (-60%), with similar results seen with ABT-894 (-60%) or nicotine (-60%). With more severe damage ( 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine 3-4x), ABT-126 and nicotine reduced dyskinesias, but ABT-894 did not. The dopamine transporter was 41% and 8.9% of control, with moderate and severe nigrostriatal damage, respectively. No drug modified parkinsonism.
Conclusion: The novel alpha 7 nicotinic receptor drug ABT-126 reduced dyskinesias in monkeys with both moderate and severe nigrostriatal damage. ABT-126 may be useful to reduce dyskinesias in both early-and later-stage Parkinson's disease.

• 出版日期2015-12