Treatment with the anitoxidant coenzyme Q10 does not improve symptoms in patients with mid-stage Parkinson's disease,according to a report in the "Archives of Neurology".Earlier work suggested that coenzyme Q10 protects nerves by restoring normal energy metabolism,which could benefit Parkinson's patients,the investigators write.There is also evidence that high levels of coenzyme Q10 supplements slow the deterioration associated with this disease.