title: Neuropathology provides clues to the pathophysiology of Gaucher disease.
abstract: To better understand the pathogenesis of brain dysfunction in Gaucher disease (GD), we studied brain pathology in seven subjects with type 1 GD (four also exhibited parkinsonism and dementia), three with type 2 GD and four with type 3 GD. Unique pathologic patterns of disease involving the hippocampal CA2-4 regions and layer 4b of the calcarine cortex were identified. While these findings were common to all three GD phenotypes, the extent of the changes varied depending on the severity of disease. Cerebral cortical layers 3 and 5, hippocampal CA2-4, and layer 4b were involved in all GD patients. Neuronal loss predominated in both type 2 and type 3 patients with progressive myoclonic encephalopathy, whereas patients classified as type 1 GD had only astrogliosis. Adjacent regions and lamina, including hippocampal CA1 and calcarine lamina 4a and 4c were spared of pathology, highlighting the specificity of the vulnerability of selective neurons. Elevated glucocerebrosidase expression by immunohistochemistry was found in CA2-4. Hippocampal (45)Ca(2+) uptake autoradiography in rat brain was performed demonstrating that hippocampal CA2-4 neurons, rather than CA1 neurons, were calcium-induced calcium release sensitive (CICR-sensitive). These findings match recent biochemical studies linking elevated glucosylceramide levels to sensitization of CA2-4 RyaR receptors and 300% potentiation of neuronal CICR sensitivity. In two patients with type 1 GD and parkinsonism, numerous synuclein positive inclusions, similar to brainstem-type Lewy bodies found in Parkinson disease, were also found hippocampal CA2-4 neurons. These findings argue for a common cytotoxic mechanism linking aberrant glucocerebrosidase activity, neuronal cytotoxicity, and cytotoxic Lewy body formation in GD.
authors.affiliation: Department of Neuropathology at the Armed Forces Institute of Pathology, Washington, DC, USA.
authors.forename: Kondi
authors.initials: K
authors.lastname: Wong
authors.forename: Ellen
authors.initials: E
authors.lastname: Sidransky
authors.forename: Ajay
authors.initials: A
authors.lastname: Verma
authors.forename: Tonghui
authors.initials: T
authors.lastname: Mixon
authors.forename: Glenn D
authors.initials: GD
authors.lastname: Sandberg
authors.forename: Laura K
authors.initials: LK
authors.lastname: Wakefield
authors.forename: Alan
authors.initials: A
authors.lastname: Morrison
authors.forename: Alicia
authors.initials: A
authors.lastname: Lwin
authors.forename: Carlos
authors.initials: C
authors.lastname: Colegial
authors.forename: John M
authors.initials: JM
authors.lastname: Allman
authors.forename: Raphael
authors.initials: R
authors.lastname: Schiffmann
mesh_terms: D000293:Adolescent; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001253:Astrocytes / Q000473:pathology; D001345:Autoradiography; D001921:Brain / Q000473:pathology*; D002132:Calcium Radioisotopes / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D004831:Epilepsies, Myoclonic / Q000150:complications; D005260:Female; D005776:Gaucher Disease / Q000150:complications / Q000503:physiopathology*; D005962:Glucosylceramidase / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D008297:Male; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009474:Neurons / Q000473:pathology*; D051381:Rats; D051843:Synucleins
chemical_list: D002132:Calcium Radioisotopes; D009419:Nerve Tissue Proteins; D051843:Synucleins; D005962:Glucosylceramidase