Kazuki Ide1, Hiroshi Yamada2, Keizo Umegaki3, Katsuki Mizuno1, Nobuko Kawakami4, Yuka Hagiwara4, Mizuki Matsumoto4, Hidefumi Yoshida4, Kang Kim4, Emi Shiosaki5, Tsunehiro Yokochi5, Kiyoshi Harada4. 1. Department of Drug Evaluation and Informatics, Graduate School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan. 2. Department of Drug Evaluation and Informatics, Graduate School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan; Department of Neurology, Shizuoka General Hospital, Shizuoka, Japan. Electronic address: hyamada@u-shizuoka-ken.ac.jp. 3. National Institute of Health and Nutrition, Tokyo, Japan. 4. Department of Neurology, Shizuoka General Hospital, Shizuoka, Japan. 5. Department of Clinical Laboratory Medicine, Shizuoka General Hospital, Shizuoka, Japan.
Abstract
OBJECTIVES: 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.
OBJECTIVES: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.