title: Diffuse Optical Spectroscopy and Imaging to Detect and Quantify Adipose Tissue Browning.
abstract: Adipose (fat) tissue is a complex metabolic organ that is highly active and essential. In contrast to white adipose tissue (WAT), brown adipose tissue (BAT) is deemed metabolically beneficial because of its ability to burn calories through heat production. The conversion of WAT-resident adipocytes to "beige" or "brown-like" adipocytes has recently attracted attention. However, it typically takes a few days to analyze and confirm this browning of WAT through conventional molecular, biochemical, or histological methods. Moreover, accurate quantification of the overall browning process is not possible by any of these methods. In this context, we report the novel application of diffuse reflectance spectroscopy (DRS) and multispectral imaging (MSI) to detect and quantify the browning process in mice. We successfully demonstrated the time-dependent increase in browning of WAT, following its induction through β-adrenergic agonist injections. The results from these optical techniques were confirmed with those of standard molecular and biochemical assays, which measure gene and protein expression levels of UCP1 and PGC-1α, as well as with histological examinations. We envision that the reported optical methods can be developed into a fast, real time, cost effective and easy to implement imaging approach for quantification of the browning process in adipose tissue.
authors.affiliation: Bio Optical Imaging Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore.
authors.forename: U S
authors.initials: US
authors.lastname: Dinish
authors.affiliation: Bio Optical Imaging Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore.
authors.forename: Chi Lok
authors.initials: CL
authors.lastname: Wong
authors.affiliation: Fat Metabolism and Stem Cell Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore.
authors.forename: Sandhya
authors.initials: S
authors.lastname: Sriram
authors.affiliation: Fat Metabolism and Stem Cell Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore.
authors.forename: Wee Kiat
authors.initials: WK
authors.lastname: Ong
authors.affiliation: Bio Optical Imaging Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore.
authors.forename: Ghayathri
authors.initials: G
authors.lastname: Balasundaram
authors.affiliation: Fat Metabolism and Stem Cell Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore.|Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, Singapore.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Sugii
authors.affiliation: Bio Optical Imaging Group, Singapore Bioimaging Consortium, Agency for Science Technology and Research (A*STAR), Singapore.|School of Physics, National University of Ireland Galway, Ireland.
authors.forename: Malini
authors.initials: M
authors.lastname: Olivo
mesh_terms: D017667:Adipocytes / Q000187:drug effects / Q000378:metabolism; D002001:Adipose Tissue, Brown / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D004149:Dioxoles / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D021621:Imaging, Three-Dimensional; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D055100:Optical Fibers; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013057:Spectrum Analysis / Q000379:methods*; D000071256:Uncoupling Protein 1 / Q000378:metabolism
chemical_list: D015415:Biomarkers; D004149:Dioxoles; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; C485290:Ppargc1a protein, mouse; D012333:RNA, Messenger; D000071256:Uncoupling Protein 1; C076126:disodium (R,R)-5-(2-((2-(3-chlorophenyl)-2-hydroxyethyl)-amino)propyl)-1,3-benzodioxole-2,3-dicarboxylate