Lymphocyte vitamin C levels as potential biomarker for progression of Parkinson's disease
Nutrition Volume 31, Issue 2, February 2015, Pages 406–408 Kazuki Ide
•Parkinson's disease (PD) is the second most common neurodegenerative disorder in the world.
•Oxidative stress may be a factor; vitamin C is an antioxidant and neuromodulator.
•We assessed plasma and lymphocyte vitamin C levels in patients with PD.
•Lymphocyte vitamin C levels were decreased in the severe stages of PD.
•Lymphocyte vitamin C levels may be a useful biomarker for PD progression.
Vitamin C is a major antioxidant and also is known as a neuromodulator in dopaminergic neurons. The aim of this study was to investigate the association between lymphocyte and plasma vitamin C levels in various stages of Parkinson's disease (PD).
Methods
Sixty-two individuals with PD (age 71 ± 8.8 y [mean ± SD]) being treated at Shizuoka General Hospital from December 2007 to August 2013 were consecutively recruited. PD severity was classified using the Hoehn-Yahr scale for staging PD. Fasting blood samples were collected, and plasma and lymphocyte vitamin C levels were measured. The association between PD severity and vitamin C levels was estimated by ordinal logistic regression with confounding variables.
Results
The distribution of Hoehn-Yahr stages in patients was as follows: stage I, 7; II, 28; III, 16; and IV, 11. Lymphocyte vitamin C levels in patients with severe PD were significantly lower (odds ratio [OR], 0.87; 95% confidence interval [CI], 0.80–0.97; P < 0.01) compared with those at less severe stages. Plasma vitamin C levels also tended to be lower in patients with severe PD; however, this was not significant (OR, 0.98; 95% CI, 0.96–1.00; P = 0.09).
Conclusions
Our findings suggest that lymphocyte vitamin C levels in the peripheral blood may be a potentially useful biomarker for the progression of PD.