title: Nonlinear microscopy of lipid storage and fibrosis in muscle and liver tissues of mice fed high-fat diets.
abstract: Hallmarks of high-fat Western diet intake, such as excessive lipid accumulation in skeletal muscle and liver as well as liver fibrosis, are investigated in tissues from mice using nonlinear microscopy, second harmonic generation (SHG), and coherent anti-Stokes Raman scattering (CARS), supported by conventional analysis methods. Two aspects are presented; intake of standard chow versus Western diet, and a comparison between two high-fat Western diets of different polyunsaturated lipid content. CARS microscopy images of intramyocellular lipid droplets in muscle tissue show an increased amount for Western diet compared to standard diet samples. Even stronger diet impact is found for liver samples, where combined CARS and SHG microscopy visualize clear differences in lipid content and collagen fiber development, the latter indicating nonalcoholic fatty liver disease (NAFLD) and steatohepatitis induced at a relatively early stage for Western diet. Characteristic for NAFLD, the fibrous tissue-containing lipids accumulate in larger structures. This is also observed in CARS images of liver samples from two Western-type diets of different polyunsaturated lipid contents. In summary, nonlinear microscopy has strong potential (further promoted by technical advances toward clinical use) for detection and characterization of steatohepatitis already in its early stages.
authors.affiliation: Chalmers University of Technology, Department of Chemical and Biological Engineering, Molecular Microscopy, 412 96 Göteborg, Sweden.
authors.forename: Christian
authors.initials: C
authors.lastname: Brackmann
authors.forename: Britt
authors.initials: B
authors.lastname: Gabrielsson
authors.forename: Fredrik
authors.initials: F
authors.lastname: Svedberg
authors.forename: Agneta
authors.initials: A
authors.lastname: Holmaang
authors.forename: Ann-Sofie
authors.initials: AS
authors.lastname: Sandberg
authors.forename: Annika
authors.initials: A
authors.lastname: Enejder
mesh_terms: D000818:Animals; D004041:Dietary Fats / Q000378:metabolism*; D005355:Fibrosis / Q000378:metabolism* / Q000473:pathology; D050356:Lipid Metabolism; D008099:Liver / Q000378:metabolism* / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008853:Microscopy / Q000379:methods*; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000473:pathology; D017711:Nonlinear Dynamics; D014018:Tissue Distribution
chemical_list: D004041:Dietary Fats