title: Antioxidant and inflammatory biomarkers for the identification of prodromal Parkinson's disease.
abstract: OBJECTIVE
  We explored the role of oxidative stress and inflammatory molecules as potential Parkinson (PD) biomarkers and correlated biological with non-motor abnormalities (olfactory impairment and dysautonomia), in patients with idiopathic REM behavior disorder (iRBD) (prodromal PD) and established PD.
  
  
  METHODS
  We recruited 11 iRBD and 15 patients with idiopathic PD (Hohen&Yahr 1-3, on L-DOPA and dopamine agonists combination therapy) and 12 age- and sex-matched controls (CTRL). We measured total olfactory score (TOS), autonomic function [deep breathing (DB), lying to standing (LS) and Valsalva manoeuvre (VM) ratios], blood reduced glutathione (Br-GSH), oxidative stress and inflammatory markers (neopterin).
  
  
  RESULTS
  Anosmia was similarly prevalent in iRBD (36%) and PD (33%) patients, but absent in CTRL. Orthostatic hypotension was more common among iRBD (73%) and PD (60%) than in CTRL (25%). By univariable ordinal logistic regression, TOS, Br-GSH, LS and VM ratio worsened from CTRL to iRBD and PD groups. Only reduced Br-GSH levels (p=0.037, OR=0.994; 95%CI 0.988-1.000) were independently associated to PD. TOS correlated with Br-GSH (R=0.34, p=0.037), VM ratio (R=0.43, p=0.015), and neopterin (rho=0.39, p=0.016).
  
  
  CONCLUSIONS
  Reduced systemic antioxidant capacity is found in prodromal and overt PD and may represent, in association with olfactory loss and cardiovascular dysautonomia, a useful biomarker for an integrative, early diagnosis of PD.
authors: CNR Institute of Clinical Physiology, ASST- Great Metropolitan Hospital Niguarda, Milan, Italy.
authors: Jonica
authors: J
authors: Campolo
authors: CNR Institute of Clinical Physiology, ASST- Great Metropolitan Hospital Niguarda, Milan, Italy. Electronic address: renata_de_maria@hotmail.com.
authors: Renata
authors: R
authors: De Maria
authors: CNR Institute of Clinical Physiology, ASST- Great Metropolitan Hospital Niguarda, Milan, Italy.
authors: Lorena
authors: L
authors: Cozzi
authors: CNR Institute of Clinical Physiology, ASST- Great Metropolitan Hospital Niguarda, Milan, Italy.
authors: Marina
authors: M
authors: Parolini
authors: CNR Institute of Clinical Physiology, ASST- Great Metropolitan Hospital Niguarda, Milan, Italy.
authors: Stefano
authors: S
authors: Bernardi
authors: Epilepsy Surgery Centre, Centre of Sleep Medicine, ASST- Great Metropolitan Hospital Niguarda, Milan, Italy.
authors: Paola
authors: P
authors: Proserpio
authors: Epilepsy Surgery Centre, Centre of Sleep Medicine, ASST- Great Metropolitan Hospital Niguarda, Milan, Italy.
authors: Lino
authors: L
authors: Nobili
authors: Neurology and Stoke Unit, Department of Neuroscience, ASST-Great Metropolitan Hospital Niguarda, Milan, Italy.
authors: Giorgio
authors: G
authors: Gelosa
authors: Spinal Unit, ASST- Great Metropolitan Hospital Niguarda, Milan, Italy.
authors: Immacolata
authors: I
authors: Piccolo
authors: Neurology and Stoke Unit, Department of Neuroscience, ASST-Great Metropolitan Hospital Niguarda, Milan, Italy.
authors: Elio C
authors: EC
authors: Agostoni
authors: CNR Institute of Clinical Physiology, ASST- Great Metropolitan Hospital Niguarda, Milan, Italy.
authors: Maria G
authors: MG
authors: Trivella
authors: CNR Institute of Clinical Physiology, ASST- Great Metropolitan Hospital Niguarda, Milan, Italy.
authors: Paolo
authors: P
authors: Marraccini
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000627:therapeutic use; D015415:Biomarkers / Q000378:metabolism; D018491:Dopamine Agonists / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D005260:Female; D005978:Glutathione / Q000097:blood; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D019798:Neopterin / Q000652:urine; D010300:Parkinson Disease / Q000175:diagnosis* / Q000188:drug therapy / Q000378:metabolism*; D062706:Prodromal Symptoms; D012903:Smell; D014636:Valsalva Maneuver
chemical_list: D000978:Antiparkinson Agents; D015415:Biomarkers; D018491:Dopamine Agonists; D007980:Levodopa; D019798:Neopterin; D005978:Glutathione
keywords: Cardiac dysautonomia; Glutathione; Idiopathic REM behavior disorder; Olfactory dysfunction; Parkinson's disease