The majority of lipoprotein lipase in plasma is bound to remnant lipoproteins: A new definition of remnant lipoproteins

Koichi Sato, Fumikazu Okajima, Kazuya Miyashita, Shigeyuki Imamura, Junji Kobayashi, Kimber Stanhope, Peter J Havel, Tetsuo Machida, Hiroyuki Sumino, Masami Murakami, Ernst Schaefer, Katsuyuki Nakajima

Research output: Contribution to journalArticle

12 Scopus citations

Abstract

Background Lipoprotein lipase (LPL) is a multifunctional protein and a key enzyme involved in the regulation of lipoprotein metabolism. We determined the lipoproteins to which LPL is bound in the pre-heparin and post-heparin plasma. Methods Tetrahydrolipstatin (THL), a potent inhibitor of serine lipases, was used to block the lipolytic activity of LPL, thereby preventing changes in the plasma lipoproteins due to ex vivo lipolysis. Gel filtration was performed to obtain the LPL elution profiles in plasma and the isolated remnant lipoproteins (RLP). Results When ex vivo lipolytic activity was inhibited by THL in the post-heparin plasma, majority of the LPL was found in the VLDL elution range, specifically in the RLP as inactive dimers. However, in the absence of THL, most of the LPL was found in the HDL elution range as active dimers. Furthermore, majority of the LPL in the pre-heparin plasma was found in the RLP as inactive form, with broadly diffused lipoprotein profiles in the presence and absence of THL. Conclusions It is suggested that during lipolysis in vivo, the endothelial bound LPL dimers generates RLP, forming circulating RLP-LPL complexes in an inactive form that subsequently binds and initiates receptor-mediated catabolism.

Original languageEnglish (US)
Pages (from-to)114-125
Number of pages12
JournalClinica Chimica Acta
Volume461
DOIs
StatePublished - Oct 1 2016

    Fingerprint

Keywords

  • Chylomicron remnants (CM-R)
  • Lipoprotein lipase (LPL)
  • Remnant-like lipoprotein particles-cholesterol (RLP-C)
  • Tetrahydrolipstatin (THL)
  • Very low density lipoprotein remnants (VLDL-R)

ASJC Scopus subject areas

  • Biochemistry
  • Clinical Biochemistry
  • Biochemistry, medical

Cite this

Sato, K., Okajima, F., Miyashita, K., Imamura, S., Kobayashi, J., Stanhope, K., Havel, P. J., Machida, T., Sumino, H., Murakami, M., Schaefer, E., & Nakajima, K. (2016). The majority of lipoprotein lipase in plasma is bound to remnant lipoproteins: A new definition of remnant lipoproteins. Clinica Chimica Acta, 461, 114-125. https://doi.org/10.1016/j.cca.2016.06.020