title: Augmenting CNS glucocerebrosidase activity as a therapeutic strategy for parkinsonism and other Gaucher-related synucleinopathies.
abstract: Mutations of GBA1, the gene encoding glucocerebrosidase, represent a common genetic risk factor for developing the synucleinopathies Parkinson disease (PD) and dementia with Lewy bodies. PD patients with or without GBA1 mutations also exhibit lower enzymatic levels of glucocerebrosidase in the central nervous system (CNS), suggesting a possible link between the enzyme and the development of the disease. Previously, we have shown that early treatment with glucocerebrosidase can modulate α-synuclein aggregation in a presymptomatic mouse model of Gaucher-related synucleinopathy (Gba1(D409V/D409V)) and ameliorate the associated cognitive deficit. To probe this link further, we have now evaluated the efficacy of augmenting glucocerebrosidase activity in the CNS of symptomatic Gba1(D409V/D409V) mice and in a transgenic mouse model overexpressing A53T α-synuclein. Adeno-associated virus-mediated expression of glucocerebrosidase in the CNS of symptomatic Gba1(D409V/D409V) mice completely corrected the aberrant accumulation of the toxic lipid glucosylsphingosine and reduced the levels of ubiquitin, tau, and proteinase K-resistant α-synuclein aggregates. Importantly, hippocampal expression of glucocerebrosidase in Gba1(D409V/D409V) mice (starting at 4 or 12 mo of age) also reversed their cognitive impairment when examined using a novel object recognition test. Correspondingly, overexpression of glucocerebrosidase in the CNS of A53T α-synuclein mice reduced the levels of soluble α-synuclein, suggesting that increasing the glycosidase activity can modulate α-synuclein processing and may modulate the progression of α-synucleinopathies. Hence, increasing glucocerebrosidase activity in the CNS represents a potential therapeutic strategy for GBA1-related and non-GBA1-associated synucleinopathies, including PD.
authors.affiliation: Genzyme, a Sanofi Company, Framingham, MA 01701, USA. pablo.sardi@genzyme.com
authors.forename: S Pablo
authors.initials: SP
authors.lastname: Sardi
authors.forename: Jennifer
authors.initials: J
authors.lastname: Clarke
authors.forename: Catherine
authors.initials: C
authors.lastname: Viel
authors.forename: Monyrath
authors.initials: M
authors.lastname: Chan
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Tamsett
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Treleaven
authors.forename: Jie
authors.initials: J
authors.lastname: Bu
authors.forename: Lindsay
authors.initials: L
authors.lastname: Sweet
authors.forename: Marco A
authors.initials: MA
authors.lastname: Passini
authors.forename: James C
authors.initials: JC
authors.lastname: Dodge
authors.forename: W Haung
authors.initials: WH
authors.lastname: Yu
authors.forename: Richard L
authors.initials: RL
authors.lastname: Sidman
authors.forename: Seng H
authors.initials: SH
authors.lastname: Cheng
authors.forename: Lamya S
authors.initials: LS
authors.lastname: Shihabuddin
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology* / Q000473:pathology / Q000503:physiopathology; D000229:Dependovirus / Q000378:metabolism; D004195:Disease Models, Animal; D005776:Gaucher Disease / Q000188:drug therapy* / Q000201:enzymology* / Q000473:pathology / Q000503:physiopathology; D005962:Glucosylceramidase / Q000008:administration & dosage / Q000235:genetics / Q000378:metabolism* / Q000627:therapeutic use; D006624:Hippocampus / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008568:Memory; D051379:Mice; D008822:Mice, Transgenic; D020734:Parkinsonian Disorders / Q000188:drug therapy* / Q000201:enzymology* / Q000503:physiopathology; D020836:Protein Structure, Quaternary; D011609:Psychosine / Q000031:analogs & derivatives / Q000378:metabolism; D051844:alpha-Synuclein / Q000235:genetics / Q000378:metabolism*; D016875:tau Proteins / Q000737:chemistry / Q000378:metabolism
chemical_list: D051844:alpha-Synuclein; D016875:tau Proteins; D011609:Psychosine; C035742:sphingosyl beta-glucoside; D005962:Glucosylceramidase