SLAS Discovery - Special Issue on Advances in MALDI Mass Spectrometry for Drug Discovery - Volume 22 Issue 10 - December 2017 - 1218

719372
research-article2017

JBXXXX10.1177/2472555217719372SLAS DISCOVERY: Advancing Life Sciences R&DJones et al.

Original Research

Tissue Localization of Glycosphingolipid
Accumulation in a Gaucher Disease Mouse
Brain by LC-ESI-MS/MS and High-Resolution
MALDI Imaging Mass Spectrometry

SLAS Discovery
2017, Vol. 22(10) 1218-1228
© 2017 Society for Laboratory
Automation and Screening
https://doi.org/10.1177/2472555217719372
DOI: 10.1177/2472555217719372
journals.sagepub.com/home/jbx

E. Ellen Jones1, Wujuan Zhang2, Xueheng Zhao2, Cristine Quiason1,
Stephanie Dale1, Sheerin Shahidi-Latham1, Gregory A. Grabowski3,
Kenneth D. R. Setchell2, Richard R. Drake4, and Ying Sun3

Abstract
To better understand regional brain glycosphingolipid (GSL) accumulation in Gaucher disease (GD) and its relationship
to neuropathology, a feasibility study using mass spectrometry and immunohistochemistry was conducted using brains
derived from a GD mouse model (4L/PS/NA) homozygous for a mutant GCase (V394L [4L]) and expressing a prosaposin
hypomorphic (PS-NA) transgene. Whole brains from GD and control animals were collected using one hemisphere for
MALDI FTICR IMS analysis and the other for quantitation by LC-ESI-MS/MS. MALDI IMS detected several HexCers across
the brains. Comparison with the brain hematoxylin and eosin (H&E) revealed differential signal distributions in the midbrain,
brain stem, and CB of the GD brain versus the control. Quantitation of serial brain sections with LC-ESI-MS/MS supported
the imaging results, finding the overall HexCer levels in the 4L/PS-NA brains to be four times higher than the control.
LC-ESI-MS/MS also confirmed that the elevated hexosyl isomers were glucosylceramides rather than galactosylceramides.
MALDI imaging also detected differential analyte distributions of lactosylceramide species and gangliosides in the 4L/PS-NA
brain, which was validated by LC-ESI-MS/MS. Immunohistochemistry revealed regional inflammation, altered autophagy,
and defective protein degradation correlating with regions of GSL accumulation, suggesting that specific GSLs may have
distinct neuropathological effects.
Keywords
glycosphingolipids, Gaucher disease, MALDI FTICR imaging, mass spectrometry, brain pathology

Introduction
Gaucher disease (GD) is an autosomal recessive lysosomal
storage disorder resulting from a mutation in GBA1, which
encodes glucocerebrosidase (GCase, EC 3.1.2.45). GCase is
the enzyme responsible for glucosylceramide (GluCer) degradation, a key step in glycosphingolipid (GSL) catabolism.1
Accordingly, GD patients present with gross accumulations of
GluCer in many organs, including the spleen, liver, lung, bone,
and in some variants, the central nervous system (CNS).2
Three phenotypes (1-3) of GD have been defined by the presence (types 2 and 3) or absence (type 1) of early-onset progressive CNS involvement.2-4 Type 2 GD presents in infancy,
usually leading to death within 1-3 years of onset, while type
3 patients generally experience a later involvement of the
CNS, often surviving for several decades. Although type 1 GD
patients experience a highly variable visceral disease and typically remain free of CNS involvement, they have a much
greater lifetime risk of developing Parkinson's disease and
Lewy body disease.5,6 Enzyme replacement therapy (ERT) has

proven successful in treating the visceral manifestations of GD
variants; however, it is unable to cross the blood-brain barrier,
1

Department of Drug Metabolism & Pharmacokinetics, Genentech Inc.,
South San Francisco, CA, USA
2
Division of Pathology and Laboratory Medicine, Cincinnati Children's
Hospital Medical Center, Cincinnati, OH, USA
3
Division of Human Genetics, Cincinnati Children's Hospital Medical
Center and the Department of Pediatrics, University of Cincinnati
College of Medicine, Cincinnati, OH, USA
4
Department of Cell and Molecular Pharmacology and MUSC
Proteomics Center, Medical University of South Carolina, Charleston,
SC, USA
Received March 3, 2017, and in revised form May 12, 2017. Accepted for
publication June 15, 2017.
Supplementary material is available online with this article.
Corresponding Author:
Ying Sun, Children's Hospital Medical Center, 3333 Burnet Ave., MLC
4006, Cincinnati, OH 45229, USA.
Email: ying.sun@cchmc.org
http://journals.sagepub.com/home/jbx
Table of Contents for the Digital Edition of SLAS Discovery - Special Issue on Advances in MALDI Mass Spectrometry for Drug Discovery - Volume 22 Issue 10 - December 2017
