10.5061/DRYAD.NG64Q
Satzer, David
University of Minnesota
DiBartolomeo, Christina
University of Minnesota
Ritchie, Michael M.
University of Minnesota
Storino, Christine
University of Minnesota
Liimatainen, Timo
University of Eastern Finland
Hakkarainen, Hanne
University of Eastern Finland
Idiyatullin, Djaudat
University of Minnesota
Mangia, Silvia
University of Minnesota
Michaeli, Shalom
University of Minnesota
Parr, Ann M.
University of Minnesota
Low, Walter C.
University of Minnesota
Data from: Assessment of dysmyelination with RAFFn MRI: application to
murine MPS I
Dryad
dataset
2015
Mus musculus
MRI
mucopolysaccharidosis
dysmyelination
2015-12-12T00:00:00Z
2015-12-12T00:00:00Z
en
https://doi.org/10.1371/journal.pone.0116788
139395556 bytes
1
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Type I mucopolysaccharidosis (MPS I) is an autosomal recessive lysosomal
storage disorder with neurological features. Humans and laboratory animals
with MPS I exhibit various white matter abnormalities involving the corpus
callosum and other regions. In this study, we first validated a novel MRI
technique, entitled Relaxation Along a Fictitious Field in the rotating
frame of rank n (RAFFn), as a measure of myelination and dysmyelination in
mice. We then examined differences between MPS I mice and heterozygotes
using RAFF5 and histology. RAFF5 (i.e., RAFFn with n = 5) relaxation time
constants were highly correlated with histological myelin density (R2 =
0.68, P<0.001), and RAFF5 clearly distinguished between the
hypomyelinated and dysmyelinated shiverer mouse and the wild-type mouse.
Bloch-McConnell theoretical analysis revealed slower exchange correlation
times and smaller exchange-induced relaxation rate constants for RAFF4 and
RAFF5 compared to RAFF1-3, T1ρ, and T2ρ. These data suggest that RAFF5 may
assess methylene protons in myelin lipids and proteins, though other
mechanisms (e.g. detection of myelin-bound water) may also explain the
sensitivity of RAFF5 to myelin. In MPS I mice, mean RAFF5 relaxation time
constants were significantly larger for the striatum (P = 0.004) and
internal capsule (P = 0.039), and marginally larger for the fornix (P =
0.15). Histological assessment revealed no differences between MPS I mice
and heterozygotes in myelin density or corpus callosum thickness. Taken
together, these findings support subtle dysmyelination in the brains of
mice with MPS I. Dysmyelination may result from myelin lipid abnormalities
caused by the absence of α-L-iduronidase. Our findings may help to explain
locomotor and cognitive deficits seen in mice with MPS I.
Histology imagesZipped folder containing photomicrographs of mouse brain
sections. Sections are from MPS I mice and IDUA heterozygotes, and are
stained with the black gold stain. Images have been resized and converted
to grayscale. Images are scaled to 173 pixels per millimeter unless noted
otherwise in the filename (“..._NotToScale”). Files are titled
"histology_[mouse identifier]_[tissue section identifier].tif".
Mice 13021, 13224, 13255, N3, N4, and N5 are mice with MPS I; mice 13257,
13258, N1, N2, and N6 are heterozygotes.Histology analysis_for DryadExcel
spreadsheet containing analyzed histological data. The “Optical density”
tab contains raw optical density values for each tissue section,
normalized values, normalized means for each animal, and normalized means
for each genotype. The “Outliers” tab contains analysis of each animal for
outlying values (see the publication in PLOS ONE for details). The “cc
thickness” tab contains raw data for corpus callosum thickness, comparison
with atlas values for each section, animal means, and genotype means. Mice
13021, 13224, 13255, N3, N4, and N5 are mice with MPS I; mice 13257,
13258, N1, N2, and N6 are heterozygotes.MRI relaxation time constant
mapsZipped folder containing MRI relaxation time constant maps. Files are
meant to be opened and analyzed using the Aedes toolbox for MATLAB. See
the publication in PLOS ONE for more details. Files are titled "MRI
_[mouse identifier]_[MRI sequence].t1r [or .t1]". Mice 13021, 13224,
13255, N3, N4, and N5 are mice with MPS I; mice 13257, 13258, N1, N2, and
N6 are heterozygotes.MRI analysis_for DryadExcel spreadsheet containing
analyzed MRI data. The “MRI ROI comparison” tab contains mean relaxation
time constants for each ROI in each animal for each sequence, as well as
means for each genotype. The “MRI vs histology” tab contains correlation
of tissue section-derived normalized optical density with MRI relaxation
time constants for each MRI sequence. The “Outliers” tab contains analysis
of each animal for outlying values (see the publication in PLOS ONE for
details). Mice 13021, 13224, 13255, N3, N4, and N5 are mice with MPS I;
mice 13257, 13258, N1, N2, and N6 are heterozygotes.