title: Randomized, double-blind, placebo-controlled pilot trial of reduced coenzyme Q10 for Parkinson's disease.
abstract: BACKGROUND
  Mitochondrial complex I deficiencies have been found in post-mortem brains of patients with Parkinson's disease (PD). Coenzyme Q10 (CoQ10) is the electron acceptor found in complexes I and II, and is a potent antioxidant. A recent trial of the oxidized form of CoQ10 for PD failed to show benefits; however, the reduced form of CoQ10 (ubiquinol-10) has shown better neuroprotective effects in animal models.
  
  
  METHODS
  Randomized, double-blind, placebo-controlled, parallel-group pilot trials were conducted to assess the efficacy of ubiquinol-10 in Japanese patients with PD. Participants were divided into two groups: PD experiencing wearing off (Group A), and early PD, without levodopa (with or without a dopamine agonist) (Group B). Participants took 300 mg of ubiquinol-10 or placebo per day for 48 weeks (Group A) or 96 weeks (Group B).
  
  
  RESULTS
  In Group A, total Unified Parkinson's Disease Rating Scale (UPDRS) scores decreased in the ubiquinol-10 group (n = 14; mean ± SD [-4.2 ± 8.2]), indicating improvement in symptoms. There was a statistically significant difference (p < 0.05) compared with the placebo group (n = 12; 2.9 ± 8.9). In Group B, UPDRS increased in the ubiquinol-10 group (n = 14; 3.9 ± 8.0), as well as in the placebo group (n = 8; 5.1 ± 10.3).
  
  
  CONCLUSIONS
  This is the first report showing that ubiquinol-10 may significantly improve PD with wearing off, as judged by total UPDRS scores, and that ubiquinol-10 is safe and well tolerated.
authors.affiliation: Department of Neurology, Juntendo University School of Medicine, Japan; Department of Neurology, Juntendo University Koshigaya Hospital, Japan.
authors.forename: Asako
authors.initials: A
authors.lastname: Yoritaka
authors.affiliation: Department of Neurology, Juntendo University School of Medicine, Japan.
authors.forename: Sumihiro
authors.initials: S
authors.lastname: Kawajiri
authors.affiliation: School of Bioscience and Biotechnology, Tokyo University of Technology, Japan.
authors.forename: Yorihiro
authors.initials: Y
authors.lastname: Yamamoto
authors.affiliation: Department of Neurology, Juntendo University School of Medicine, Japan.
authors.forename: Toshiki
authors.initials: T
authors.lastname: Nakahara
authors.affiliation: Department of Neurology, Juntendo University School of Medicine, Japan.
authors.forename: Maya
authors.initials: M
authors.lastname: Ando
authors.affiliation: School of Bioscience and Biotechnology, Tokyo University of Technology, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Hashimoto
authors.affiliation: School of Bioscience and Biotechnology, Tokyo University of Technology, Japan.
authors.forename: Midori
authors.initials: M
authors.lastname: Nagase
authors.affiliation: Department of Neurology, Higashi Nagoya National Hospital, Japan.
authors.forename: Yufuko
authors.initials: Y
authors.lastname: Saito
authors.affiliation: Department of Neurology, Juntendo University School of Medicine, Japan. Electronic address: nhattori@juntendo.ac.jp.
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Hattori
mesh_terms: D000368:Aged; D000975:Antioxidants / Q000008:administration & dosage / Q000494:pharmacology*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018696:Neuroprotective Agents / Q000008:administration & dosage / Q000494:pharmacology*; D010300:Parkinson Disease / Q000188:drug therapy*; D010865:Pilot Projects; D016896:Treatment Outcome; D014451:Ubiquinone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D018696:Neuroprotective Agents; D014451:Ubiquinone; C024989:coenzyme Q10; C003741:ubiquinol
keywords: Complex I; Oxidative stress; Parkinson's disease; Randomized controlled trial; Reduced form of coenzyme Q10