Glycosaminoglycan storage in neuroanatomical regions of mucopolysaccharidosis I dogs following intrathecal recombinant human iduronidase
Chen A, Vogler C, McEntee M, Hanson S, Ellinwood MN, Jens J, Snella E, Passage M, Le S, Guerra C, Dickson P. Glycosaminoglycan storage in neuroanatomical regions of mucopolysaccharidosis I dogs following intrathecal recombinant human iduronidase. APMIS 2011; 119: 513–21.
(IT) recombinant human α‐l‐iduronidase (rhIDU) has been shown to reduce mean brain glycosaminoglycans (GAGs) to normal levels in mucopolysaccharidosis I (MPS I) dogs. In this study, we examined storage in neuroanatomical regions of the MPS I dog brain,
including frontal lobe, cerebellum, basal ganglia, thalamus, hippocampal formation, and brainstem, to determine the response of these functional regions to treatment with IT rhIDU. GAG storage in untreated MPS I dogs was significantly different from normal dogs in all examined sections. GAG
levels in normal dogs varied by region: frontal lobe (mean: 2.36 ± 0.54 μg/mg protein), cerebellum (2.67 ± 0.33), basal ganglia and thalamus (3.51 ± 0.60), hippocampus (3.30 ± 0.40), and brainstem (3.73 ± 1.10).
Following IT treatment, there was a reduction in GAG storage in each region in all treatment groups, except for the brainstem. Percent reduction in GAG levels from untreated to treated MPS I dogs in the deeper regions of the brain was 30% for basal ganglia and thalamus and 30% for hippocampus,
and storage reduction was greater in superficial regions, with 61% reduction in the frontal lobe and 54% in the cerebellum compared with untreated MPS I dogs. Secondary lipid storage in neurons was also reduced in frontal lobe, but not in the other brain regions examined. Response to therapy
appeared to be greater in more superficial regions of the brain, particularly in the frontal lobe cortex.
Document Type: Research Article
Division of Pediatric Neurology, Department of Pediatrics, LABioMed at Harbor-UCLA Medical Center, Torrance, CA
Department of Pathology, St. Louis School of Medicine, St. Louis, MO
Department of Pathobiology, College of Veterinary Medicine, University of Tennessee, Knoxville, TN
Veterinary Neurology Center, Tustin, CA
Department of Animal Science and the Center for Integrated Animal Genomics, Iowa State University, Ames, IA
Division of Medical Genetics, Department of Pediatrics
Biological Resources Center, LABioMed at Harbor-UCLA Medical Center, Torrance, CA, USA
Publication date: 2011-08-01