The secretome of brown adipose tissue
2014 (English)Doctoral thesis, comprehensive summary (Other academic)
Brown adipose tissue has long been known for its heat-producing capacity, but less is known about its possible effects as a secretory organ. This thesis summarizes information about presently known factors secreted from brown adipose tissue and about their actions. We were able to add factors to the list by the use of a signal-sequence trap method. Results from the signal-sequence trap generated a list of suggested brown adipocyte secreted proteins; gene expression of these proteins was then further studied with microarray technique.
One of the genes further analyzed was the adipokine chemerin. Gene expression of chemerin in brown adipose tissue was decreased in cold acclimation but increased with a high-caloric diet. This indicates that factors other than norepinephrine influence chemerin gene expression. The effects on chemerin gene expression were not be reflected in serum levels; therefore, chemerin secreted from brown adipose tissue is ascribed an autocrine/paracrine role.
Signal-sequence trap and microarray studies suggested adrenomedullin, collagen type 3 a1, lipocalin 2 and Niemann Pick type C2 to be highly secreted from brown adipocytes. Gene expression of these factors was examined in vivo and in vitro. Our studies showed that both cold acclimation and high-caloric diet have an effect on gene expression of these factors. However, there was no effect on gene expression of chemerin and collagen type 3 a1 in norepinephrine-treated brown adipocyte cell cultures. This suggests that effects on gene expression of the examined possible brown adipocyte secreted proteins are not solely controlled by norepinephrine.
Place, publisher, year, edition, pages
Stockholm: Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University , 2014. , 101 p.
Biochemistry and Molecular Biology
Research subject Physiology
IdentifiersURN: urn:nbn:se:su:diva-102934ISBN: 978-91-7447-903-4OAI: oai:DiVA.org:su-102934DiVA: diva2:714076
2014-05-28, Lecture hall E306, Arrheniuslaboratorierna, Svante Arrhenius väg 20 C, Stockholm, 10:00 (English)
Nedergaard, Jan, Proffesor
At the time of doctoral defence the following papers were unpublished and had a status as follows: Paper 1: Manuscript; Paper 3: Manuscript; Paper 4: Manuscript; Paper 5: Manuscript2014-05-062014-04-252014-04-28Bibliographically approved
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