gms | German Medical Science

Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2016)

25.10. - 28.10.2016, Berlin

Adipocyte lipoprotein lipase links systemic lipid transport to bone matrix and bone marrow fatty acid profile

Meeting Abstract

  • presenting/speaker Andreas Niemeier - Universitätsklinikum Hamburg-Eppendorf, Klinik und Poliklinik für Orthopädie, Hamburg, Germany
  • Till Köhne - Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
  • Brigitte Müller - Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
  • Wolfgang Rüther - Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
  • Jörg Heeren - Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
  • Alexander Bartelt - Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany

Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2016). Berlin, 25.-28.10.2016. Düsseldorf: German Medical Science GMS Publishing House; 2016. DocGR18-306

doi: 10.3205/16dkou460, urn:nbn:de:0183-16dkou4602

Veröffentlicht: 10. Oktober 2016

© 2016 Niemeier et al.
Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). Lizenz-Angaben siehe http://creativecommons.org/licenses/by/4.0/.


Gliederung

Text

Objectives: Adipocytes are master regulators of energy homeostasis. Although the contribution of classical brown and white adipose tissue (BAT or WAT) to glucose and fatty acid metabolism are well characterized, the metabolic role of adipocytes in bone marrow remains elusive. Here we characterize skeletal fatty acid metabolism and its contribution to systemic nutrient glucose and lipid handling in mice.

Methods: Organ uptake of radiolabeled glucose and fatty acids after oral gavage was measured by standard methods. Bone structure was determined by histomorphometry and µCT and levels of biochemical bone turnover markers by commercially available kits. Lipid profiles were measured high resolution gas chromatography. Animals carrying floxed alleles of lipoprotein lipase (LPL) as well as mice expressing Cre recombinase under control of the Fabp4 promoter were purchased from Jackson Labs.

Results and Conclusion: Whereas in parts of the skeleton the specific amount of fatty acids taken-up from the circulation was lower than in other metabolically active tissues such as BAT or liver, the overall contribution of the skeleton as a whole organ was quantitatively important, placing the skeleton among the top organs involved in systemic glucose as well as fatty acid clearance. We show that, especially in the bone marrow of the tibia, the fatty acid profile resembles classical BAT and WAT. Using a mouse model lacking LPL as a master regulator of plasma lipid turnover specifically in adipocytes, we show that impaired fatty acid flux leads to reduced amounts of dietary essential fatty acids in both bone marrow and cortical bone while there was a profound increase in de novo produced fatty acids in both bone marrow and cortical bone.

In conclusion, we demonstrate that systemic fatty acid metabolism is intricately linked to local fatty acid metabolism in bone marrow and bone matrix.