Apoptosis inhibitor of macrophage (AIM) diminishes lipid droplet-coating proteins leading to lipolysis in adipocytes

Biochemical and Biophysical Research Communications
Yoshihiro IwamuraToru Miyazaki

Abstract

Under fasting conditions, triacylglycerol in adipose tissue undergoes lipolysis to supply fatty acids as energy substrates. Such lipolysis is regulated by hormones, which activate lipases via stimulation of specific signalling cascades. We previously showed that macrophage-derived soluble protein, AIM induces obesity-associated lipolysis, triggering chronic inflammation in fat tissue which causes insulin resistance. However, the mechanism of how AIM mediates lipolysis remains unknown. Here we show that AIM induces lipolysis in a manner distinct from that of hormone-dependent lipolysis, without activation or augmentation of lipases. In vivo and in vitro, AIM did not enhance phosphorylation of hormone-sensitive lipase (HSL) in adipocytes, a hallmark of hormone-dependent lipolysis activation. Similarly, adipose tissue from obese AIM-deficient and wild-type mice showed comparable HSL phosphorylation. Consistent with the suppressive effect of AIM on fatty acid synthase activity, the amount of saturated and unsaturated fatty acids was reduced in adipocytes treated with AIM. This response ablated transcriptional activity of peroxisome proliferator-activated receptor (PPARγ), leading to diminished gene expression of lipid-droplet coati...Continue Reading

References

Aug 7, 1972·Biochemical and Biophysical Research Communications·D VanceK Bloch
Dec 22, 1999·Current Opinion in Cell Biology·Z WuB M Spiegelman
May 24, 2001·Proceedings of the National Academy of Sciences of the United States of America·J T TanseyC Londos
Dec 4, 2003·Biochemical Society Transactions·C Holm
Dec 17, 2004·Proceedings of the National Academy of Sciences of the United States of America·Annabel F ValledorChristopher K Glass
Feb 15, 2005·Biochemical and Biophysical Research Communications·Bernhard SchmidBradford S Hamilton
May 14, 2005·Current Opinion in Lipidology·Rudolf ZechnerRobert Zimmermann
Feb 23, 2007·Annual Review of Nutrition·Robin E DuncanHei Sook Sul
Aug 19, 2007·Clinical Chemistry·Bevin GangadharanNicole Zitzmann
Jan 19, 2008·Endocrinology·Nicole A Ducharme, Perry E Bickel
May 30, 2008·Proceedings of the National Academy of Sciences of the United States of America·Vishwajeet PuriMichael P Czech
Jul 26, 2008·The Journal of Clinical Investigation·Vishwajeet Puri, Michael P Czech
Jan 16, 2009·International Journal of Obesity : Journal of the International Association for the Study of Obesity·M Lafontan
Nov 23, 2010·Progress in Lipid Research·Achim LassRudolf Zechner
May 19, 2011·Current Opinion in Clinical Nutrition and Metabolic Care·David L MorrisCarey N Lumeng
Jul 7, 2011·Proceedings of the National Academy of Sciences of the United States of America·Jun KurokawaToru Miyazaki

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Citations

Nov 28, 2013·Seminars in Immunopathology·Satoko Arai, Toru Miyazaki
Oct 7, 2014·Cell Reports·Natsumi MaeharaToru Miyazaki
Feb 15, 2013·Wiley Interdisciplinary Reviews. Systems Biology and Medicine·Sara ManteigaKyongbum Lee
Jun 17, 2016·Molecular & Cellular Oncology·Toru Miyazaki, Satoko Arai
Jul 16, 2016·FEBS Open Bio·Mai Thi Nhu TranSatoru Takahashi
Oct 13, 2016·Scientific Reports·Ryoichi SugisawaToru Miyazaki
Jan 30, 2018·Cellular & Molecular Immunology·Toru MiyazakiSatoko Arai
Dec 9, 2016·Scientific Reports·Tomoko YamazakiToru Miyazaki
Sep 5, 2018·Scientific Reports·Ryoichi SugisawaToru Miyazaki
Jun 7, 2015·Journal of Leukocyte Biology·Lucía SanjurjoMaria-Rosa Sarrias
Dec 4, 2013·Journal of Leukocyte Biology·Núria AmézagaMaria-Rosa Sarrias
Mar 7, 2021·International Journal of Molecular Sciences·Hao Wei, Ji-Yang Wang
May 1, 2021·International Journal of Molecular Sciences·Lidia Sanchez-MoralMaria-Rosa Sarrias

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