Molecular Features of Parkinson's Disease in Patient-Derived Midbrain Dopaminergic Neurons.

BACKGROUND: Despite intense efforts to develop an objective diagnostic test for Parkinson's disease, there is still no consensus on biomarkers that can accurately diagnose the disease. OBJECTIVE: Identification of biomarkers for idiopathic Parkinson's disease (PD) may enable accurate diagnosis of the disease. We tried to find molecular and cellular differences in dopaminergic (DA) neurons derived from healthy subjects and idiopathic PD patients with or without rest tremor at onset. METHODS: We measured the expression of genes controlling dopamine synthesis, sequestration, and catabolism as well as the levels of corresponding metabolites and reactive oxygen species in midbrain DA neurons differentiated from induced pluripotent stem cells (iPSCs) of healthy subjects and PD patients with or without rest tremor. RESULTS: Significant differences in DA-related gene expression, metabolites, and oxidative stress were found between midbrain DA neurons derived from healthy subjects and patients with PD. DA neurons derived from PD patients with or without rest tremor at onset exhibited significant differences in the levels of some of these transcripts, metabolites, and oxidative stress. CONCLUSION: The unique combination of these quantifiable molecular and cellular traits in iPSC-derived midbrain DA neurons can distinguish healthy subjects from idiopathic PD patients and segregate PD patients with or without rest tremor at onset. The strategy may be used to develop an objective diagnostic test for PD.

Pilot study using gabapentin for tamoxifen-induced hot flashes in women with breast cancer.

In this pilot study, 22 women with breast cancer on tamoxifen therapy with at least two hot flashes a day took oral gabapentin at 300 mg three times a day for 4 weeks. The 16 women who completed the study had a mean decrease in hot flash duration of 73.6% (P = 0.027), frequency of 44.2% (P < 0.001), and severity of 52.6% (P < 0.001), with a complete response in 8/16 women. Side effects reported by four women who did not complete 4 weeks of the study were nausea (1/4), rash (1/4) and excessive sleepiness (3/4). Two additional patients did not provide complete data. Gabapentin is a promising new agent in the treatment of tamoxifen induced hot flashes, and should be studied further.