Mov Disord: In early Parkinson's patients, how does the neurotransmitter of cerebrospinal fluid change?

Parkinson's disease (PD) is characterized by the gradual loss of dopaminergic neurons next to the substantia nigra, but there is also the consumption of other neurotransmitters, such as serotonin in the striatum and norepinephrine in the hypothalamus and frontal cortex

Although the quantification of CSF biomarkers has improved the early diagnosis of Alzheimer's disease , there are no similar protein biomarkers for PD diagnosis

Studies have found that the levels of dopamine metabolites in PD, especially the main dopamine metabolite homovanillic acid (homovanillic acid, HVA), decrease

Despite efforts to standardize the collection, processing, and measurement of CSF, potential confounding factors for catecholamine levels still exist (for example, diurnal changes, total CSF) and may hinder reliable quantitative analysis

Although high performance liquid chromatography with electrochemical detection (HPLC-ECD) and gas chromatography-mass spectrometry were previously considered the gold standard for the analysis of dopamine and its metabolites, LC-MS/MS (liquid chromatography and tandem mass spectrometry) It has been developed in the past 20 years, and its sensitivity is comparable to that of HPLC-ECD, and its selectivity is greatly enhanced

LC-MS/MS reduces the complexity of pre-analysis processing and is now considered the gold standard for quantitative analysis

The absolute levels of multiple monoamine metabolites in the CSF of 161 early-stage Parkinson's disease patients and 115 HCs in the PPMI and new-onset Parkinson's disease (DeNoPA) study were quantitatively analyzed by liquid chromatography-tandem mass spectrometry

They found that compared with HCs, PD patients had lower baseline levels of HVA and 3,4-dihydroxyphenylacetic acid (DOPAC)

The original DOPAC was correlated with the putamen dopamine transporter single-photon emission computed tomography uptake rate (P <0.

The metabolites of those without drug treatment did not change within 2 years, but some metabolites changed when levodopa treatment was started

The significance of this study is that it was found that the CSF levels of HVA and DOPAC reflect the damage of the substantia nigra pathway, confirming the core role of dopaminergic degeneration in early PD