title: Protective Effect of Astaxanthin on Vocal Fold Injury and Inflammation Due to Vocal Loading: A Clinical Trial.
abstract: OBJECTIVE
  Professional voice users, such as singers and teachers, are at greater risk of developing vocal fold injury from excessive use of voice; thus, protection of the vocal fold is essential. One of the most important factors that aggravates injury is the production of reactive oxygen species at the wound site. The purpose of the current study was to assess the effect of astaxanthin, a strong antioxidant, on the protection of the vocal fold from injury and inflammation due to vocal loading.
  
  
  METHODS
  This study is an institutional review board-approved human clinical trial.
  
  
  METHODS
  Ten male subjects underwent a 60-minute vocal loading session and received vocal assessments prior to, immediately after, and 30 minutes postvocal loading (AST(-) status). All subjects were then prescribed 24 mg/day of astaxanthin for 28 days, after which they received the same vocal task and assessments (AST(+) status). Phonatory parameters were compared between both groups.
  
  
  RESULTS
  Aerodynamic assessment, acoustic analysis, and GRBAS scale (grade, roughness, breathiness, asthenia, and strain) were significantly worse in the AST(-) status immediately after vocal loading, but improved by 30 minutes after loading. In contrast, none of the phonatory parameters in the AST(+) status were statistically worse, even when measured immediately after vocal loading. No allergic responses or adverse effects were observed after administration of astaxanthin.
  
  
  CONCLUSIONS
  The current results suggest that astaxanthin can protect the vocal fold from injury and inflammation caused by vocal loading possibly through the regulation of oxidative stress.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Mami
authors.initials: M
authors.lastname: Kaneko
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Yo
authors.initials: Y
authors.lastname: Kishimoto
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Suzuki
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Kawai
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Tateya
authors.affiliation: Department of Otolaryngology Head & Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan. Electronic address: hirano@koto.kpu-m.ac.jp.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Hirano
mesh_terms: D000162:Acoustics; D000328:Adult; D000893:Anti-Inflammatory Agents / Q000009:adverse effects / Q000627:therapeutic use*; D000975:Antioxidants / Q000009:adverse effects / Q000627:therapeutic use*; D001307:Auditory Perception; D019610:Cytoprotection; D004185:Disability Evaluation; D006801:Humans; D007600:Judgment; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D010699:Phonation / Q000187:drug effects; D012649:Self Concept; D049489:Stroboscopy; D013997:Time Factors; D016896:Treatment Outcome; D014827:Vocal Cords / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D014832:Voice Disorders / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology / Q000517:prevention & control*; D014833:Voice Quality / Q000187:drug effects*; D024341:Xanthophylls / Q000009:adverse effects / Q000627:therapeutic use; D055815:Young Adult
chemical_list: D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D024341:Xanthophylls; C005948:astaxanthine
keywords: Astaxanthin; Clinical trial; Reactive oxygen species; Vocal fold; Vocal loading