Parkinson's disease treatments of the future

Authors reviewing new therapeutic strategies for Parkinson's disease say that advances in neuroprotective and neurorestorative strategies will provide a more promising future for patients with Parkinson's disease. The authors review the results of animal studies and clinical trials on a range of new treatments undergoing investigation. These include new symptomatic, neuroprotective and neurorestorative agents. The authors say it is an exciting time for Parkinson's disease research and, "the time is ripe for the beginning of a new phase of treatment strategies."Nondopaminergic symptomatic therapies under investigation include adenosine A2A antagonists, such as istradefylline, AMPA receptor antagonists, and monoamine reuptake inhibitors, such as NS-2330.Neuroprotective and neurorestorative therapies are also currently under investigation. These include coenzyme Q10, an antioxidant that has shown benefits in a range of diseases and being studied to clarify its role in Parkinson's disease. CEP-1347, an anti-apoptotic agent, has also shown early promise, and trials are continuing in the assessment of its neuroprotective effects.The rapidly-developing area of gene therapy may provide a genetic alternative to surgery or deep brain stimulation in the form of glutamic acid decarboxylase (GAD) gene transfer in the subthalamic nucleus. The authors explain, "GAD is the enzyme that converts glutamate to the major inhibitory neurotransmitter in the brain, GABA. The aim of subthalamic GAD gene transfer is not only to inhibit the subthalamic nucleus, but also to change the nature of its output neurons from excitatory to inhibitory, i.e. result in a virally-induced subthalamotomy."Glial cell line-derived neurotrophic factor (GDNF) has shown promise in non-human primate models of Parkinson's disease using various delivery mechanisms. Its use in humans requires further investigation, and the review authors outline a number of issues that need consideration. They conclude, "The choice of patients and target sites will ultimately influence the potential benefits of GDNF administration."Reference...