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Title: The adaptor protein alpha-syntrophin regulates adipocyte lipid droplet growth

Abstract

The scaffold protein alpha-syntrophin (SNTA) regulates lipolysis indicating a role in lipid homeostasis. Adipocytes are the main lipid storage cells in the body, and here, the function of SNTA has been analyzed in 3T3-L1 cells. SNTA is expressed in preadipocytes and is induced early during adipogenesis. Knock-down of SNTA in preadipocytes increases their proliferation. Proteins which are induced during adipogenesis like adiponectin and caveolin-1, and the inflammatory cytokine IL-6 are at normal levels in the mature cells differentiated from preadipocytes with low SNTA. This suggests that SNTA does neither affect differentiation nor inflammation. Expression of proteins with a role in cholesterol and triglyceride homeostasis is unchanged. Consequently, basal and epinephrine induced lipolysis as well as insulin stimulated phosphorylation of Akt and ERK1/2 are normal. Importantly, adipocytes with low SNTA form smaller lipid droplets and store less triglycerides. Stearoyl-CoA reductase and MnSOD are reduced upon SNTA knock-down but do not contribute to lower lipid levels. Oleate uptake is even increased in cells with SNTA knock-down. In summary, current data show that SNTA is involved in the expansion of lipid droplets independent of adipogenesis. Enhanced preadipocyte proliferation and capacity to store surplus fatty acids may protect adipocytes with low SNTA from lipotoxicitymore » in obesity. - Highlights: • Alpha-syntrophin (SNTA) is expressed in 3T3-L1adipocytes. • SNTA knock-down in preadipocytes has no effect on adipogenesis. • Mature 3T3-L1 differentiated from cells with low SNTA form small lipid droplets. • SCD1 and MnSOD are reduced in adipocytes with low SNTA. • SCD1 knock-down does not alter triglyceride levels.« less

Authors:
; ; ; ; ;
Publication Date:
OSTI Identifier:
22648589
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Cell Research; Journal Volume: 345; Journal Issue: 1; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; ADRENALINE; CARBOXYLIC ACIDS; CELL PROLIFERATION; CHOLESTEROL; COBALT ARSENIDES; COMMERCIAL BUILDINGS; DROPLETS; HOMEOSTASIS; INFLAMMATION; INSULIN; LYMPHOKINES; METABOLIC DISEASES; OXIDOREDUCTASES; PHOSPHORYLATION; PLANT GROWTH; TRIGLYCERIDES; UPTAKE

Citation Formats

Eisinger, Kristina, Rein-Fischboeck, Lisa, Pohl, Rebekka, Meier, Elisabeth M., Krautbauer, Sabrina, and Buechler, Christa, E-mail: christa.buechler@klinik.uni-regensburg.de. The adaptor protein alpha-syntrophin regulates adipocyte lipid droplet growth. United States: N. p., 2016. Web. doi:10.1016/J.YEXCR.2016.05.020.
Eisinger, Kristina, Rein-Fischboeck, Lisa, Pohl, Rebekka, Meier, Elisabeth M., Krautbauer, Sabrina, & Buechler, Christa, E-mail: christa.buechler@klinik.uni-regensburg.de. The adaptor protein alpha-syntrophin regulates adipocyte lipid droplet growth. United States. doi:10.1016/J.YEXCR.2016.05.020.
Eisinger, Kristina, Rein-Fischboeck, Lisa, Pohl, Rebekka, Meier, Elisabeth M., Krautbauer, Sabrina, and Buechler, Christa, E-mail: christa.buechler@klinik.uni-regensburg.de. 2016. "The adaptor protein alpha-syntrophin regulates adipocyte lipid droplet growth". United States. doi:10.1016/J.YEXCR.2016.05.020.
@article{osti_22648589,
title = {The adaptor protein alpha-syntrophin regulates adipocyte lipid droplet growth},
author = {Eisinger, Kristina and Rein-Fischboeck, Lisa and Pohl, Rebekka and Meier, Elisabeth M. and Krautbauer, Sabrina and Buechler, Christa, E-mail: christa.buechler@klinik.uni-regensburg.de},
abstractNote = {The scaffold protein alpha-syntrophin (SNTA) regulates lipolysis indicating a role in lipid homeostasis. Adipocytes are the main lipid storage cells in the body, and here, the function of SNTA has been analyzed in 3T3-L1 cells. SNTA is expressed in preadipocytes and is induced early during adipogenesis. Knock-down of SNTA in preadipocytes increases their proliferation. Proteins which are induced during adipogenesis like adiponectin and caveolin-1, and the inflammatory cytokine IL-6 are at normal levels in the mature cells differentiated from preadipocytes with low SNTA. This suggests that SNTA does neither affect differentiation nor inflammation. Expression of proteins with a role in cholesterol and triglyceride homeostasis is unchanged. Consequently, basal and epinephrine induced lipolysis as well as insulin stimulated phosphorylation of Akt and ERK1/2 are normal. Importantly, adipocytes with low SNTA form smaller lipid droplets and store less triglycerides. Stearoyl-CoA reductase and MnSOD are reduced upon SNTA knock-down but do not contribute to lower lipid levels. Oleate uptake is even increased in cells with SNTA knock-down. In summary, current data show that SNTA is involved in the expansion of lipid droplets independent of adipogenesis. Enhanced preadipocyte proliferation and capacity to store surplus fatty acids may protect adipocytes with low SNTA from lipotoxicity in obesity. - Highlights: • Alpha-syntrophin (SNTA) is expressed in 3T3-L1adipocytes. • SNTA knock-down in preadipocytes has no effect on adipogenesis. • Mature 3T3-L1 differentiated from cells with low SNTA form small lipid droplets. • SCD1 and MnSOD are reduced in adipocytes with low SNTA. • SCD1 knock-down does not alter triglyceride levels.},
doi = {10.1016/J.YEXCR.2016.05.020},
journal = {Experimental Cell Research},
number = 1,
volume = 345,
place = {United States},
year = 2016,
month = 7
}
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