Fecal Tyrosine Decarboxylase and Motor Response Complications in Parkinson's Disease

This study examined whether gut bacterial tyrosine decarboxylase (TDC), which metabolizes levodopa, is associated with motor complications in 178 Parkinson's disease patients. While patients with dyskinesia and motor fluctuations showed 2-3 fold higher fecal TDC levels, differences were not statistically significant, suggesting a potential but unproven relationship between microbiota-derived enzymes and treatment response variability.