title: Two-photon excited fluorescence of intrinsic fluorophores enables label-free assessment of adipose tissue function.
abstract: Current methods for evaluating adipose tissue function are destructive or have low spatial resolution. These limit our ability to assess dynamic changes and heterogeneous responses that occur in healthy or diseased subjects, or during treatment. Here, we demonstrate that intrinsic two-photon excited fluorescence enables functional imaging of adipocyte metabolism with subcellular resolution. Steady-state and time-resolved fluorescence from intracellular metabolic co-factors and lipid droplets can distinguish the functional states of excised white, brown, and cold-induced beige fat. Similar optical changes are identified when white and brown fat are assessed in vivo. Therefore, these studies establish the potential of non-invasive, high resolution, endogenous contrast, two-photon imaging to identify distinct adipose tissue types, monitor their functional state, and characterize heterogeneity of induced responses.
authors.affiliation: Department of Biomedical Engineering, Tufts University 4 Colby Street, Medford, MA 02155, USA.
authors.forename: Carlo Amadeo
authors.initials: CA
authors.lastname: Alonzo
authors.affiliation: Biomedical Research Foundation, Academy of Athens, Athens, Greece.
authors.forename: Sevasti
authors.initials: S
authors.lastname: Karaliota
authors.affiliation: Department of Biomedical Engineering, Tufts University 4 Colby Street, Medford, MA 02155, USA.
authors.forename: Dimitra
authors.initials: D
authors.lastname: Pouli
authors.affiliation: Department of Biomedical Engineering, Tufts University 4 Colby Street, Medford, MA 02155, USA.
authors.forename: Zhiyi
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Biomedical Research Foundation, Academy of Athens, Athens, Greece.|Endocrine Division, Children's Hospital, Boston, MA 02115, USA.
authors.forename: Katia P
authors.initials: KP
authors.lastname: Karalis
authors.affiliation: Department of Biomedical Engineering, Tufts University 4 Colby Street, Medford, MA 02155, USA.
authors.forename: Irene
authors.initials: I
authors.lastname: Georgakoudi
mesh_terms: D017667:Adipocytes / Q000502:physiology*; D000273:Adipose Tissue / Q000502:physiology*; D006801:Humans; D061848:Optical Imaging / Q000379:methods*