Change in plasma exosome α-synuclein in patients with rapid eye movement sleep behavior disorder or Parkinson disease / 中风与神经疾病杂志

ABSTRACT

@#Objective To quantitatively analyze the difference in the content of plasma exosome α-synuclein（α-syn）between Parkinson disease （PD） and idiopathic rapid eye movement sleep behavior disorder（iRBD），and to identify predictable biological markers. Methods A total of 20 patients with iRBD（iRBD group），21 PD patients without RBD （PD-nRBD group），and 20 healthy controls matched for age and sex（HC group） were enrolled. Rapid-Eye-Movement Sleep Behavior Disorder Questionnaire-Hong Kong（RBDQ-HK）was used to evaluate the nocturnal symptoms of all subjects，and the motor section of Unified Parkinson Disease Rating Scale Ⅲ（UPDRS Ⅲ）was used to evaluate motor impairment. ELISA was used to measure the content of plasma exosome α-syn，and the three groups were analyzed in terms of the content of plasma exosome α-syn and its correlation with RBDQ-HK score and UPDRS Ⅲ score. Results There was a significant difference in UPDRS Ⅲ score between the iRBD group，the PD-nRBD group，and the HC group（P=0.000 1），with a significant difference between any two groups （P<0.05）；there was also a significant difference in RBDQ-HK score between the three groups （P=0.000 1），and the iRBD group had a significantly higher score than the other two groups（P=0.000 1）.The iRBD group and the PD-nRBD group had a significantly higher content of plasma exosome α-syn than the HC group（P=0.001），and the iRBD group had a lower content of plasma exosome α-syn than the PD-nRBD group（P>0.05）. In the iRBD group，plasma exosome α-syn was positively correlated with RBDQ-HK score（r=0.842，P=0.000 1），and in the PD-nRBD group，plasma exosome α-syn was positively correlated with UPDRS Ⅲ score（r=0.817，P=0.000 1） and H-Y staging（r=0.592，P=0.005）. Conclusion The presence of plasma exosome α-syn is observed in iRBD patients，which is similar to that in PD-nRBD patients，and the content of plasma exosome α-syn is associated with the motor score of PD-nRBD and the nocturnal symptom score of iRBD. Therefore，plasma exosome α-syn is expected to become an early biomarker for predicting the conversion of iRBD to PD.