Science exchange logo white
  • Solutions
      Buyers

      We are making R&D services readily available to every organization that seeks to make scientific impact. Learn More

      Providers

      We are changing the way providers access and engage customers to streamline the sale and delivery of R&D services. Learn More

      Industries Agriscience Animal Health Basic Research Biopharmaceutical Chemicals Consumer Health Food Science Medical Devices
      Reproducibility

      We believe that good experiments can and should be independently replicated and validated. Learn More

  • Resources
    Innovation Blog
    Customer Stories
    Events
    Industry Trends
    News
    Product Updates
    Help Center
  • About
    About
    Our Story
    Leadership
    Partners
    Join the Team
  • Contact
  • Log In Sign Up
  • Get a Demo
  • Intracellular Cholesterol Binding Proteins Enhance HDL-mediated Cholesterol Uptake in Cultured Primary Mouse Hepatocytes.

    Am J Physiol Gastrointest Liver Physiol. doi: 10.1152/ajpgi.00195.2011. January 12, 2012. View on PubMed.
  • Authors

    Harold Ross Payne (Texas A&M University), Storey SM, McIntosh AL, Huang H, Landrock KK, Martin GG, Landrock D, Atshaves BP, Kier AB, and Schroeder F
  • Abstract

    A major gap in our knowledge of rapid hepatic HDL cholesterol clearance is the role of key intracellular factors that influence this process. Although the reverse cholesterol transport pathway targets HDL to the liver for net elimination of free cholesterol from the body, molecular details governing cholesterol uptake into hepatocytes are not completely understood. Therefore, the effects of sterol carrier protein (SCP)-2 and liver fatty acid-binding protein (L-FABP), high-affinity cholesterol-binding proteins present in hepatocyte cytosol, on HDL-mediated free cholesterol uptake were examined using gene-targeted mouse models, cultured primary hepatocytes, and 22-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-amino]-23,24-bisnor-5-cholen-3β-ol (NBD-cholesterol). While SCP-2 overexpression enhanced NBD-cholesterol uptake, counterintuitively, SCP-2/SCP-x gene ablation also 1) enhanced the rapid molecular phase of free sterol uptake detectable in <1 min and initial rate and maximal uptake of HDL free cholesterol and 2) differentially enhanced free cholesterol uptake mediated by the HDL3, rather than the HDL2, subfraction. The increased HDL free cholesterol uptake was not due to increased expression or distribution of the HDL receptor [scavenger receptor B1 (SRB1)], proteins regulating SRB1 [postsynaptic density protein (PSD-95)/Drosophila disk large tumor suppressor (dlg)/tight junction protein (ZO1) and 17-kDa membrane-associated protein], or other intracellular cholesterol trafficking proteins (steroidogenic acute response protein D, Niemann Pick C, and oxysterol-binding protein-related proteins). However, expression of L-FABP, the single most prevalent hepatic cytosolic protein that binds cholesterol, was upregulated twofold in SCP-2/SCP-x null hepatocytes. Double-immunogold electron microscopy detected L-FABP sufficiently close to SRB1 for direct interaction, similar to SCP-2. These data suggest a role for L-FABP in HDL cholesterol uptake, a finding confirmed with SCP-2/SCP-x/L-FABP null mice and hepatocytes. Taken together, these results suggest that L-FABP, particularly in the absence of SCP-2, plays a significant role in HDL-mediated cholesterol uptake in cultured primary hepatocytes.

Science exchange logo white

  • Facebook
  • Twitter
  • LinkedIn

Solutions

  • Buyers
  • Providers
  • Reproducibility

Industries

  • Agriscience
  • Animal Health
  • Basic Research
  • Biopharmaceutical
  • Chemicals
  • Consumer Health
  • Food Science
  • Medical Devices

Resources

  • Innovation Blog
  • Customer Stories
  • Events
  • Industry Trends
  • News
  • Product Updates

About

  • Our Story
  • Leadership
  • Partners
  • Join the Team

Support

  • Contact Us
  • Help Center
  • Trust
  • Terms of Use
  • Privacy Policy

Copyright © 2021 Science Exchange, Inc. All rights reserved.