title: Retinoids and retinoid-metabolic gene expression in mouse adipose tissues.
abstract: Vitamin A and its analogs (retinoids) regulate adipocyte differentiation. Recent investigations have demonstrated a relationship among retinoids, retinoid-binding-protein 4 (RBP4) synthesized in adipose tissues, and insulin-resistance status. In this study, we measured retinoid levels and analyzed the expression of retinoid homeostatic genes associated with retinol uptake, esterification, oxidation, and catabolism in subcutaneous (Sc) and visceral (Vis) mouse fat tissues. Both Sc and Vis depots were found to contain similar levels of all-trans retinol. A metabolite of retinol with characteristic ultraviolet absorption maxima for 9-cis retinol was observed in these 2 adipose depots, and its level was 2-fold higher in Sc than in Vis tissues. Vis adipose tissue expressed significantly higher levels of RBP4, CRBP1 (intracellular retinol-binding protein 1), RDH10 (retinol dehydrogenase), as well as CYP26A1 and B1 (retinoic acid (RA) hydroxylases). No differences in STRA6 (RBP4 receptor), LRAT (retinol esterification), CRABP1 and 2 (intracellular RA-binding proteins), and RALDH1 (retinal dehydrogenase) mRNA expressions were discerned in both fat depots. RALDH1 was identified as the only RALDH expressed in both Sc and Vis adipose tissues. These results indicate that Vis is more actively involved in retinoid metabolism than Sc adipose tissue.
authors.affiliation: Laboratory of Nutrition and Cancer, Centre de recherche, Centre hospitalier de l'Université de Montréal - Hôtel-Dieu, Montreal, QC H2W 1T7, Canada.
authors.forename: Aurelia
authors.initials: A
authors.lastname: Sima
authors.forename: Daniel-Constantin
authors.initials: DC
authors.lastname: Manolescu
authors.forename: Pangala
authors.initials: P
authors.lastname: Bhat
mesh_terms: D000429:Alcohol Oxidoreductases / Q000235:genetics / Q000378:metabolism; D000080924:Aldehyde Dehydrogenase 1 Family; D000818:Animals; D015153:Blotting, Western; D002851:Chromatography, High Pressure Liquid; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism; D057075:Enzyme Assays; D005786:Gene Expression Regulation; D050152:Intra-Abdominal Fat / Q000166:cytology / Q000378:metabolism*; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D050697:Retinal Dehydrogenase / Q000235:genetics / Q000378:metabolism; D000072516:Retinoic Acid 4-Hydroxylase; D012176:Retinoids / Q000235:genetics / Q000378:metabolism*; D054839:Retinol-Binding Proteins, Plasma / Q000235:genetics / Q000378:metabolism; D050151:Subcutaneous Fat / Q000166:cytology / Q000378:metabolism*
chemical_list: D007527:Isoenzymes; D012333:RNA, Messenger; C502487:Rbp4 protein, mouse; D012176:Retinoids; D054839:Retinol-Binding Proteins, Plasma; D003577:Cytochrome P-450 Enzyme System; D000429:Alcohol Oxidoreductases; C113992:trans-retinol dehydrogenase; C000607080:Cyp26a1 protein, mouse; D000072516:Retinoic Acid 4-Hydroxylase; D000080924:Aldehyde Dehydrogenase 1 Family; C515028:ALDH1A1 protein, mouse; D050697:Retinal Dehydrogenase