Comparative analysis of acid sphingomyelinase distribution in the CNS of rats and mice following intracerebroventricular delivery

• Published in: PloS one Vol. 6; no. 1; p. e16313
• Main Authors: Treleaven, Christopher M, Tamsett, Thomas, Fidler, Jonathan A, Taksir, Tatyana V, Cheng, Seng H, Shihabuddin, Lamya S, Dodge, James C
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 25-01-2011; Public Library of Science (PLoS)
• Subjects: Abnormalities; Acids; Animals; Biology; Body weight; Brain; Central nervous system; Central Nervous System - enzymology; Comparative analysis; Disease; Dosage; Dose-Response Relationship, Drug; Drug dosages; Drug therapy; Enzymes; Fibroblasts; Health aspects; Infusions, Intraventricular; Medicine; Mice; Nervous system; Niemann-Pick disease; Organ Specificity; Parenchyma; Pathology; Peptides; Rats; Rodents; Sphingomyelin phosphodiesterase; Sphingomyelin Phosphodiesterase - metabolism; Spinal cord; United States > US; Massachusetts
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0016313

Niemann-Pick A (NPA) disease is a lysosomal storage disorder (LSD) caused by a deficiency in acid sphingomyelinase (ASM) activity. Previously, we reported that biochemical and functional abnormalities observed in ASM knockout (ASMKO) mice could be partially alleviated by intracerebroventricular (ICV) infusion of hASM. We now show that this route of delivery also results in widespread enzyme distribution throughout the rat brain and spinal cord. However, enzyme diffusion into CNS parenchyma did not occur in a linear dose-dependent fashion. Moreover, although the levels of hASM detected in the rat CNS were determined to be within the range shown to be therapeutic in ASMKO mice, the absolute amounts represented less than 1% of the total dose administered. Finally, our results also showed that similar levels of enzyme distribution are achieved across rodent species when the dose is normalized to CNS weight as opposed to whole body weight. Collectively, these data suggest that the efficacy observed following ICV delivery of hASM in ASMKO mice could be scaled to CNS of the rat.