Comparative Analysis Of Serum Alpha-Synuclein Levels In Parkinson’s Disease And Essential Tremor Groups

Abstract

Introduction: Parkinson’s disease (PD) and essential tremor (ET) are common movement disorders with overlapping symptoms such as tremor. However, their pathophysiological mechanisms differ. PD is a neurodegenerative disorder associated with alpha-synuclein accumulation, while ET is characterized by motor dysfunction without confirmed neurodegeneration. This study investigates serum alpha-synuclein levels as a biomarker for differentiating PD and ET.

Methods: The study included 111 participants divided into three groups: 31 PD patients (mean age: 58.71±10.81 years), 50 ET patients (mean age: 42.36±14.90 years), and 30 healthy controls (mean age: 40.80±12.90 years). Serum alpha-synuclein levels were measured using ELISA. Statistical analysis included ANOVA, t-tests, and correlation analysis (significance level: p < 0.05).

Results: Serum alpha-synuclein levels were significantly higher in PD (754.64±105.8 pg/mL) compared to ET (711.05±173.5 pg/mL) and controls (13.9±9.4 pg/mL) (p < 0.001). ET patients also exhibited elevated alpha-synuclein levels relative to controls, suggesting early neurodegenerative processes. PD was associated with acute progression, while ET showed chronic progression with longer disease duration. A history of ET was noted in 19% of PD patients, indicating a potential link between the disorders.

Discussion: Elevated alpha-synuclein levels in PD confirm its role as a biomarker of neurodegeneration. While ET patients showed lower levels than PD, their elevation suggests possible early neurodegeneration. These findings highlight alpha-synuclein’s potential for differential diagnosis. Study limitations include small sample size and lack of long-term follow-up.

Conclusion: Serum alpha-synuclein is a promising biomarker for distinguishing PD and ET. Future research should explore multi-biomarker panels and longitudinal assessments to enhance diagnostic accuracy.