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Updated: Jul 4, 2025
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In vivo Liver Endocytosis Followed by Purification of Liver Cells by Liver Perfusion
Published on: November 10, 2011
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Rat hepatocytes secrete free oligosaccharides
Chengcheng Huang1, Junichi Seino1, Akinobu Honda1
1Glycometabolic Biochemistry Laboratory, RIKEN-Cluster for Pioneering Research, Wako, Saitama, Japan.
The Journal of Biological Chemistry
|February 3, 2024
Summary
The liver secretes various free glycans, including N-glycans and sialyl lactose-type glycans, directly into the bloodstream. This study identifies primary hepatocytes as the source of these circulating free glycans.
Area of Science:
- Glycobiology
- Hepatology
- Biochemistry
Background:
- Serum-free oligosaccharides' structures have been characterized, but their formation mechanism remains unclear.
- Investigating the origin of serum glycans is crucial for understanding their biological roles.
Purpose of the Study:
- To determine if primary rat hepatocytes secrete free glycans.
- To elucidate the mechanism of serum-free glycan formation.
Main Methods:
- Primary rat hepatocytes were cultured.
- Secreted glycans in the culture medium were isolated and structurally characterized.
- The role of oligosaccharyltransferase in glycan release was investigated.
Main Results:
- Primary hepatocytes secreted diverse free oligosaccharides, including sialyl/neutral free N-glycans (FNGs) and sialyl lactose/LacNAc-type glycans.
- The structures of secreted glycans mirrored those found in rat serum.
- Evidence suggests oligosaccharyltransferase involvement in releasing serum-free N-glycans.
Conclusions:
- The liver directly secretes various types of free glycans into the serum.
- Primary hepatocytes play a key role in producing and releasing these circulating glycans.
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