3-O sulfation of heparin leads to hepatotropism and longer circulatory half-life

Authors

Colton M. Miller, University of Nebraska- LincolnFollow
Yongmei Xu, University of North Carolina, Chapel HillFollow
Katrina M. Kudrna, University of Nebraska - LincolnFollow
Blake E. Hass, University of Nebraska - Lincoln
Brianna M. Kellar, University of Nebraska- Lincoln
Andrew W. Egger, University of Nebraska - Lincoln
Jian Liu, University of North Carolina at Chapel Hill
Edward N. Harris, University of Nebraska - LincolnFollow

Document Type

Article

Date of this Version

2018

Citation

Published in Thrombosis Research 167 (2018) 80–87

doi 10.1016/j.thromres.2018.05.018

Comments

Copyright © 2018 Elsevier Ltd. Used by permission.

Abstract

Introduction: Heparins are common blood anticoagulants that are critical for many surgical and biomedical procedures used in modern medicine. In contrast to natural heparin derived from porcine gut mucosa, synthetic heparins are homogenous by mass, polymer length, and chemistry.

Materials & methods: Stable cell lines expressing the human and mouse Stabilin receptors were used to evaluate endocytosis of natural and synthetic heparin. We chemoenzymatically produced synthetic heparin consisting of 12 sugars (dodecamers) containing 14 sulfate groups resulting in a non-3-O sulfated structure (n12mer). Half of the n12mer was modified with a 3-O sulfate on a single GlcNS sugar producing the 3-O sulfated heparin (12mer). Wildtype (WT), Stabilin-1 knock-out (KO), and Stabilin-2 KO C57BL/6 mice were developed and used for metabolic studies and provided as a source for primary liver sinusoidal endothelial cells.

Results & conclusions: Human and mouse Stabilin-2 receptors had very similar endocytosis rates of both the 12mer and n12mer, suggesting that they are functionally similar in primary cells. Subcutaneous injections of the n12mer and 12mer revealed that the 12mer had a much longer half-life in circulation and a higher accumulation in liver. The n12mer never accumulated in circulation and was readily excreted by the kidneys before liver accumulation could occur. Liver sinusoidal endothelial cells from the Stabilin-2 KO mice had lower uptake rates for both dodecamers, whereas, the Stabilin-1 KO mice had lower endocytosis rates for the 12mer than the n12mer. 3-O sulfation of heparin is correlated to both a longer circulatory half-life and hepatotropism which is largely performed by the Stabilin receptors.