title: Tanycytes and a differential fatty acid metabolism in the hypothalamus.
abstract: Although the brain controls all main metabolic pathways in the whole organism, its lipid metabolism is partially separated from the rest of the body. Circulating lipids and other metabolites are taken up into brain areas like the hypothalamus and are locally metabolized and sensed involving several hypothalamic cell types. In this study we show that saturated and unsaturated fatty acids are differentially processed in the murine hypothalamus. The observed differences involve both lipid distribution and metabolism. Key findings were: (i) hypothalamic astrocytes are targeted by unsaturated, but not saturated lipids in lean mice; (ii) in obese mice labeling of these astrocytes by unsaturated oleic acid cannot be detected unless β-oxidation or ketogenesis is inhibited; (iii) the hypothalamus of obese animals increases ketone body and neutral lipid synthesis while tanycytes, hypothalamic cells facing the ventricle, increase their lipid droplet content; and (iv) tanycytes show different labeling for saturated or unsaturated lipids. Our data support a metabolic connection between tanycytes and astrocytes likely to impact hypothalamic lipid sensing. GLIA 2017;65:231-249.
authors.affiliation: Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany.
authors.forename: Kristina
authors.initials: K
authors.lastname: Hofmann
authors.affiliation: German Center for Neurodegenerative Diseases (DZNE), Bonn, D-53175, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Lamberz
authors.affiliation: Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany.
authors.forename: Kira
authors.initials: K
authors.lastname: Piotrowitz
authors.affiliation: Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany.
authors.forename: Nina
authors.initials: N
authors.lastname: Offermann
authors.affiliation: Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany.
authors.forename: Diana
authors.initials: D
authors.lastname: But
authors.affiliation: Department of Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, D-66421, Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Scheller
authors.affiliation: German Center for Neurodegenerative Diseases (DZNE), Bonn, D-53175, Germany.
authors.forename: Ashraf
authors.initials: A
authors.lastname: Al-Amoudi
authors.affiliation: Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Kuerschner
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000378:metabolism; D059305:Diet, High-Fat / Q000009:adverse effects; D004195:Disease Models, Animal; D063928:Ependymoglial Cells / Q000378:metabolism* / Q000648:ultrastructure; D027341:Excitatory Amino Acid Transporter 1 / Q000235:genetics / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism*; D005904:Glial Fibrillary Acidic Protein / Q000235:genetics / Q000378:metabolism; D007031:Hypothalamus / Q000166:cytology* / Q000378:metabolism*; D066298:In Vitro Techniques; D007657:Ketone Bodies / Q000378:metabolism; D050356:Lipid Metabolism / Q000502:physiology*; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009765:Obesity / Q000139:chemically induced / Q000473:pathology; D000076104:Oligodendrocyte Transcription Factor 2 / Q000378:metabolism; D009924:Organ Culture Techniques
chemical_list: D027341:Excitatory Amino Acid Transporter 1; D005227:Fatty Acids; D005904:Glial Fibrillary Acidic Protein; D007657:Ketone Bodies; D008164:Luminescent Proteins; D000076104:Oligodendrocyte Transcription Factor 2; C493393:Slc1a3 protein, mouse
keywords: click chemistry; lipid sensing; nutrient sensing; obesity; tanycyte