Open AccessMyoinositol CEST signal in animals with increased Iba-1 levels in response to an inflammatory challenge—Preliminary findings
Author(s) -
Maria Yanez Lopez,
MarieChristine Pardon,
Kerstin Baiker,
M. J. W. Prior,
Yuchun Ding,
Alessandra Agostini,
Bai Li,
Dorothee P. Auer,
Henryk Faas
Publication year - 2019
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0212002
Subject(s) - neuroinflammation , biomarker , magnetic resonance imaging , in vivo , neuroscience , microglia , medicine , pathology , biology , inflammation , immunology , disease , biochemistry , genetics , radiology
Neuroinflammation plays an important role in the pathogenesis of a range of brain disorders. Non-invasive imaging of neuroinflammation is critical to help improve our understanding of the underlying disease mechanisms, monitor therapies and guide drug development. Generally, MRI lacks specificity to molecular imaging biomarkers, but molecular MR imaging based on chemical exchange saturation transfer (CEST) can potentially detect changes of myoinositol, a putative glial marker that may index neuroinflammation. In this pilot study we aimed to investigate, through validation with immunohistochemistry and in vivo magnetic resonance spectroscopy (MRS), whether CEST imaging can reflect the microglial response to a mild inflammatory challenge with lipopolysaccharide (LPS), in the APPSwe/ PS1 mouse model of Alzheimer’s disease and wild type controls. The response to the immune challenge was variable and did not align with genotype. Animals with a strong response to LPS (Iba1+, n = 6) showed an increase in CEST contrast compared with those who did not (Iba1-, n = 6). Changes of myoinositol levels after LPS were not significant. We discuss the difficulties of this mild inflammatory model, the role of myoinositol as a glial biomarker, and the technical challenges of CEST imaging at 0.6ppm.