title: Photobiomodulation-induced changes in a monkey model of Parkinson's disease: changes in tyrosine hydroxylase cells and GDNF expression in the striatum.
abstract: Intracranial application of red to infrared light, known also as photobiomodulation (PBM), has been shown to improve locomotor activity and to neuroprotect midbrain dopaminergic cells in rodent and monkey models of Parkinson's disease. In this study, we explored whether PBM has any influence on the number of tyrosine hydroxylase (TH)+cells and the expression of GDNF (glial-derived neurotrophic factor) in the striatum. Striatal sections of MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-treated mice and monkeys and 6-hydroxydopamine (6OHDA)-lesioned rats that had PBM optical fibres implanted intracranially (or not) were processed for immunohistochemistry (all species) or western blot analysis (monkeys). In our MPTP monkey model, which showed a clear loss in striatal dopaminergic terminations, PBM generated a striking increase in striatal TH+cell number, 60% higher compared to MPTP monkeys not treated with PBM and 80% higher than controls. This increase was not evident in our MPTP mouse and 6OHDA rat models, both of which showed minimal loss in striatal terminations. In monkeys, the increase in striatal TH+cell number in MPTP-PBM cases was accompanied by similar increases in GDNF expression, as determined from western blots, from MPTP and control cases. In summary, these results offer insights into the mechanisms by which PBM generates its beneficial effects, potentially with the use of trophic factors, such as GDNF.
authors.affiliation: Department of Anatomy F13, University of Sydney, Sydney, 2006, Australia.
authors.forename: Nabil
authors.initials: N
authors.lastname: El Massri
authors.affiliation: Department of Anatomy F13, University of Sydney, Sydney, 2006, Australia.
authors.forename: Ana P
authors.initials: AP
authors.lastname: Lemgruber
authors.affiliation: Department of Anatomy F13, University of Sydney, Sydney, 2006, Australia.
authors.forename: Isobel J
authors.initials: IJ
authors.lastname: Rowe
authors.affiliation: University of Grenoble Alpes, CEA, LETI, CLINATEC, MINATEC Campus, 38000, Grenoble, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Moro
authors.affiliation: University of Grenoble Alpes, CEA, LETI, CLINATEC, MINATEC Campus, 38000, Grenoble, France.
authors.forename: Napoleon
authors.initials: N
authors.lastname: Torres
authors.affiliation: University of Grenoble Alpes, CEA, LETI, CLINATEC, MINATEC Campus, 38000, Grenoble, France.
authors.forename: Florian
authors.initials: F
authors.lastname: Reinhart
authors.affiliation: University of Grenoble Alpes, CEA, LETI, CLINATEC, MINATEC Campus, 38000, Grenoble, France.
authors.forename: Claude
authors.initials: C
authors.lastname: Chabrol
authors.affiliation: University of Grenoble Alpes, CEA, LETI, CLINATEC, MINATEC Campus, 38000, Grenoble, France.
authors.forename: Alim-Louis
authors.initials: AL
authors.lastname: Benabid
authors.affiliation: Department of Anatomy F13, University of Sydney, Sydney, 2006, Australia. john.mitrofanis@sydney.edu.au.
authors.forename: John
authors.initials: J
authors.lastname: Mitrofanis
mesh_terms: D000818:Animals; D002421:Caudate Nucleus / Q000378:metabolism*; D002452:Cell Count; D004195:Disease Models, Animal; D051100:Glial Cell Line-Derived Neurotrophic Factor / Q000378:metabolism*; D028022:Low-Level Light Therapy / Q000379:methods*; D008252:Macaca fascicularis; D051379:Mice; D008807:Mice, Inbred BALB C; D020734:Parkinsonian Disorders / Q000378:metabolism* / Q000628:therapy*; D011699:Putamen / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism*
chemical_list: D051100:Glial Cell Line-Derived Neurotrophic Factor; D014446:Tyrosine 3-Monooxygenase
keywords: 670 nm; 6OHDA; Caudate; MPTP; Near infrared light; Putamen