Treating dyskinesia

From Sophie Rovner's well-written article on Parkinson's disease we learned that long-term treatment with l-dopa often causes its own sometimes debilitating side effect, an involuntary writhing motion known as dyskinesia (C&EN, April 10, page 55). It seems that this drug-induced movement disorder can be mitigated by adding talampanel to the classic l-dopa therapy with peripheral decarboxylase inhibitor. Talampanel is a very potent α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-antagonist skeletal muscle relaxant, antiepileptic, and neuroprotective drug that was invented at the Institute for Drug Research in Budapest and is developed at present by Teva Ltd. AMPA receptor is a subtype of the glutamate receptors, which are the predominant types of excitatory synapses in the brain (more than 75% of them use glutamate). Talampanel abolished tremor and dyskinesia in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys and in Parkinson's patients.

There are indications that this molecule can also slow down the progressive deterioration of neurons in Parkinson's disease: Even anoxia-induced brain cell loss was decreased in various animal models of stroke.

Ferenc Andrasi
Budapest, Hungary