TY - JOUR
T1 - Effect of high dose, repeated intra-cerebrospinal fluid injection of sulphamidase on neuropathology in mucopolysaccharidosis type IIIA mice
AU - Hemsley, K. M.
AU - Beard, H.
AU - King, B. M.
AU - Hopwood, J. J.
PY - 2008/10
Y1 - 2008/10
N2 - Mucopolysaccharidosis type IIIA (MPS IIIA) is an inherited neurodegenerative lysosomal storage disorder characterized by progressive loss of learned skills, sleep disturbance and behavioural problems. Reduced activity of sulphamidase (N-sulphoglucosamine sulphohydrolase; SGSH; EC 3.10.1.1) results in intracellular accumulation of heparan sulphate (HS), with the brain as the primary site of pathology. We have used a naturally occurring MPS IIIA mouse model to determine the effectiveness of SGSH replacement through the cerebrospinal fluid (CSF) to decrease neuropathology. This is a potential therapeutic option for patients with this disorder. Mice received intra-CSF injections of recombinant human SGSH (30, 50 or 70 μg) fortnightly from 6 to 18 weeks of age, and the cumulative effect on neuropathology was examined and quantified. Anti-SGSH antibodies detected in plasma at euthanasia did not appear to impact upon the health of the mice or the experimental outcome, with significant but region-dependent and dose-dependent reductions in an HS-derived oligosaccharide observed in the brain and spinal cord using tandem mass spectrometry. SGSH infusion reduced the number of storage inclusions observed in the brain when visualized using electron microscopy, and this correlated with a significant decrease in the immunohistochemical staining of a lysosomal membrane marker. Reduced numbers of activated isolectin B4-positive microglia and glial fibrillary acidic protein-positive astrocytes were seen in many, but not all, brain regions. Significant reductions in the number of ubiquitin-positive intracellular inclusions were also observed. These outcomes show the effectiveness of this method of enzyme delivery in reducing the spectrum of neuropathological changes in murine MPS IIIA brain.
AB - Mucopolysaccharidosis type IIIA (MPS IIIA) is an inherited neurodegenerative lysosomal storage disorder characterized by progressive loss of learned skills, sleep disturbance and behavioural problems. Reduced activity of sulphamidase (N-sulphoglucosamine sulphohydrolase; SGSH; EC 3.10.1.1) results in intracellular accumulation of heparan sulphate (HS), with the brain as the primary site of pathology. We have used a naturally occurring MPS IIIA mouse model to determine the effectiveness of SGSH replacement through the cerebrospinal fluid (CSF) to decrease neuropathology. This is a potential therapeutic option for patients with this disorder. Mice received intra-CSF injections of recombinant human SGSH (30, 50 or 70 μg) fortnightly from 6 to 18 weeks of age, and the cumulative effect on neuropathology was examined and quantified. Anti-SGSH antibodies detected in plasma at euthanasia did not appear to impact upon the health of the mice or the experimental outcome, with significant but region-dependent and dose-dependent reductions in an HS-derived oligosaccharide observed in the brain and spinal cord using tandem mass spectrometry. SGSH infusion reduced the number of storage inclusions observed in the brain when visualized using electron microscopy, and this correlated with a significant decrease in the immunohistochemical staining of a lysosomal membrane marker. Reduced numbers of activated isolectin B4-positive microglia and glial fibrillary acidic protein-positive astrocytes were seen in many, but not all, brain regions. Significant reductions in the number of ubiquitin-positive intracellular inclusions were also observed. These outcomes show the effectiveness of this method of enzyme delivery in reducing the spectrum of neuropathological changes in murine MPS IIIA brain.
KW - Brain
KW - Lysosomal storage disorder
KW - Mouse model
KW - Mucopolysaccharidosis
KW - Neuropathology
KW - Sanfilippo syndrome
KW - Sulphamidase
KW - Tandem mass spectrometry
KW - Treatment
UR - http://www.scopus.com/inward/record.url?scp=52949100951&partnerID=8YFLogxK
U2 - 10.1111/j.1601-183X.2008.00413.x
DO - 10.1111/j.1601-183X.2008.00413.x
M3 - Article
C2 - 18518922
AN - SCOPUS:52949100951
VL - 7
SP - 740
EP - 753
JO - Genes, Brain and Behavior
JF - Genes, Brain and Behavior
SN - 1601-1848
IS - 7
ER -