Investigation of α-Synuclein Species in Plasma Exosomes and the Oligomeric and Phosphorylated α-Synuclein as Potential Peripheral Biomarker of Parkinson's Disease.

α-Synuclein (α-syn), especially its abnormal oligomeric and phosphorylated form, plays a critical role in the pathogenesis of Parkinson's disease (PD). Plasma exosomal α-syn species have been shown to be a promising PD biomarker. However, whether different α-syn species in plasma exosomes (the oligomeric α-syn and the Ser129 phosphorylated α-syn (p-α-syn)) which represent the PD pathogenesis in the brain could be specific peripheral PD biomarker haven't been well elucidated. In this study, we successfully extracted and identified the human plasma exosomes, and the CNS-derived exosomes were detected. The different aggregation status, localization and degradation characteristics of α-syn and p-α-syn in the plasma exosomes between PD patients and healthy controls were further analyzed. The results suggested that α-syn and p-α-syn in the plasma exosomes of PD patients showed poor solubility after protease K (PK) treatment. Aggregated α-syn and p-α-syn existed both inside and on the membrane surface of plasma exosomes. The Receiver operating characteristic (ROC) performance of α-syn oligomer/total α-syn in exosomes was moderately helpful in PD diagnosis (AUC = 0.71, sensitivity = 60.5%, specificity = 59.4%), and the ratio of p-α-syn oligomer/total p-α-syn showed similar result (AUC = 0.69, sensitivity = 60.0%, specificity = 59.5%). This study indicates that the oligomeric α-syn/total α-syn and oligomeric p-α-syn/total p-α-syn ratio in plasma exosomes may be applied to assist the PD diagnosis, which needs further research.

Pretreatment with repeated electroacupuncture attenuates transient focal cerebral ischemic injury in rats.

OBJECTIVE: To investigate whether pretreatment with repeated electroacupuncture (EA) at the Baihui acupoint could induce ischemic tolerance against transient focal cerebral ischemic injury in rats. METHODS: Thirty male Sprague-Dawley (SD) rats were randomly divided into 3 groups (n=10 for each): the control group consisted of animals receiving no treatment, the isoflurane (ISO) group had animals that inhaled 1.5% isoflurane for 30 min a day for 5 days, and animals in the EA group received electroacupuncture at the Baihui acupoint for 30 min a day for 5 days under 1.5% isoflurane anesthesia. Twenty-four hours after the last treatment, the middle cerebral artery was occluded with No. 3 nylon monofilament for 120 min. The neurological outcomes were evaluated 24 h after reperfusion. The infarct volumes were then assessed using 2% triphenyltetrazolium chloride staining after the neurological outcome evaluation. RESULTS: The neurological deficit score (NDS) of the EA group [1 (0-2)] was lower than that of the ISO group [2 (1-3)] and the control group [2 (1-4)], P < 0.05. The infarct volume of the EA group (38.3 +/- 25.4 mm(3)) was significantly smaller than that of the control group (220.5 +/- 66.0 mm(3)) and the ISO group (168.6 +/- 57.6 mm(3)) 24 h after reperfusion. CONCLUSION: Electroacupuncture at the Baihui acupoint 30 min a day for 5 days significantly reduces neurological injury induced by transient middle cerebral artery occlusion.