Your browser has javascript turned off or blocked. This will lead to some parts of our website to not work properly or at all. Turn on javascript for best performance.

The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Default user image.

Cecilia Holm

Professor

Default user image.

Decrease in intramuscular lipid droplets and translocation of HSL in response to muscle contraction and epinephrine

Author

  • Clara Prats
  • Morten Donsmark
  • Klaus Qvortrup
  • Constantine Londos
  • Carole Sztalryd
  • Cecilia Holm
  • Henrik Galbo
  • Thorkil Ploug

Summary, in English

A better understanding of skeletal muscle lipid metabolism is needed to identify the molecular mechanisms relating intramuscular triglyceride (IMTG) to muscle metabolism and insulin sensitivity. An increasing number of proteins have been reported to be associated with intracellular triglyceride (TG), among them the PAT family members: perilipin, ADRP ( for adipocyte differentiation-related protein), and TIP47 ( for tail-interacting protein of 47 kDa). Hormone-sensitive lipase (HSL) is thought to be the major enzyme responsible for IMTG hydrolysis in skeletal muscle. In adipocytes, regulation of HSL by intracellular redistribution has been demonstrated. The existence of such regulatory mechanisms in skeletal muscle has long been hypothesized but has never been demonstrated. The aim of this study was to characterize the PAT family proteins associated with IMTG and to investigate the effect of epinephrine stimulation or muscle contraction on skeletal muscle TG content and HSL intracellular distribution. Rat soleus muscles were either incubated with epinephrine or electrically stimulated for 15 min. Single muscle fibers were used for morphological analysis by confocal and transmission electron microscopy. We show a decrease in IMTG in response to both lipolytic stimuli. Furthermore, we identify two PAT family proteins, ADRP and TIP47, associated with IMTG. Finally, we demonstrate HSL translocation to IMTG and ADRP after stimulation with epinephrine or contraction.

Department/s

  • Molecular Endocrinology

Publishing year

2006

Language

English

Pages

2392-2399

Publication/Series

Journal of Lipid Research

Volume

47

Issue

11

Document type

Journal article

Publisher

American Society for Biochemistry and Molecular Biology

Topic

  • Basic Medicine

Keywords

  • adipocyte differentiation-related protein
  • hormone-sensitive lipase
  • lipid metabolism regulation
  • skeletal muscle
  • 47 kDa
  • tail-interacting protein of

Status

Published

Research group

  • Molecular Endocrinology

ISBN/ISSN/Other

  • ISSN: 1539-7262