title: Characterization of skin abnormalities in a mouse model of osteogenesis imperfecta using high resolution magnetic resonance imaging and Fourier transform infrared imaging spectroscopy.
abstract: Evaluation of the skin phenotype in osteogenesis imperfecta (OI) typically involves biochemical measurements, such as histologic or biochemical assessment of the collagen produced from biopsy-derived dermal fibroblasts. As an alternative, the current study utilized non-invasive magnetic resonance imaging (MRI) microscopy and optical spectroscopy to define biophysical characteristics of skin in an animal model of OI. MRI of skin harvested from control, homozygous oim/oim and heterozygous oim/+ mice demonstrated several differences in anatomic and biophysical properties. Fourier transform infrared imaging spectroscopy (FT-IRIS) was used to interpret observed MRI signal characteristics in terms of chemical composition. Differences between wild-type and OI mouse skin included the appearance of a collagen-depleted lower dermal layer containing prominent hair follicles in the oim/oim mice, accounting for 55% of skin thickness in these. The MRI magnetization transfer rate was lower by 50% in this layer as compared to the upper dermis, consistent with lower collagen content. The MRI transverse relaxation time, T2, was greater by 30% in the dermis of the oim/oim mice compared to controls, consistent with a more highly hydrated collagen network. Similarly, an FT-IRIS-defined measure of collagen integrity was 30% lower in the oim/oim mice. We conclude that characterization of phenotypic differences between the skin of OI and wild-type mice by MRI and FT-IRIS is feasible, and that these techniques provide powerful complementary approaches for the analysis of the skin phenotype in animal models of disease.
authors.affiliation: Magnetic Resonance Imaging and Spectroscopy Section, NIH/National Institute on Aging, Intramural Research Program, GRC 4D-08 5600 Nathan Shock Drive, Baltimore, MD 21224, USA.
authors.forename: H C
authors.initials: HC
authors.lastname: Canuto
authors.forename: K W
authors.initials: KW
authors.lastname: Fishbein
authors.forename: A
authors.initials: A
authors.lastname: Huang
authors.forename: S B
authors.initials: SB
authors.lastname: Doty
authors.forename: R A
authors.initials: RA
authors.lastname: Herbert
authors.forename: J
authors.initials: J
authors.lastname: Peckham
authors.forename: N
authors.initials: N
authors.lastname: Pleshko
authors.forename: R G
authors.initials: RG
authors.lastname: Spencer
mesh_terms: D000818:Animals; D055592:Biophysical Phenomena; D003094:Collagen / Q000378:metabolism; D004195:Disease Models, Animal; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D008810:Mice, Inbred C57BL; D010013:Osteogenesis Imperfecta / Q000150:complications* / Q000473:pathology*; D012867:Skin / Q000473:pathology; D012868:Skin Abnormalities / Q000150:complications* / Q000473:pathology*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*; D013194:Staining and Labeling
chemical_list: D003094:Collagen