HSP70 induces liver X receptor pathway activation and cholesterol reduction in vitro and in vivo
Author(s)
Type
Journal Article
Abstract
OBJECTIVE: Heat Shock Proteins (HSPs) maintain cellular homeostasis under stress. HSP70 represents a major stress-inducible family member and has been identified as a druggable target in inherited cholesterol-sphingolipid storage diseases. We investigated if HSP70 modulates cholesterol accumulation in more common conditions related to atherogenesis. METHODS: We studied the effects of recombinant HSP70 in cholesterol-laden primary macrophages from human blood donors and pharmacological HSP70 upregulation in high-cholesterol diet fed zebrafish. RESULTS: Recombinant HSP70 facilitated cholesterol removal from primary human macrophage foam cells. RNA sequencing revealed that HSP70 induced a robust transcriptional re-programming, including upregulation of key targets of liver X receptors (LXR), master regulators of whole-body cholesterol removal. Mechanistically, HSP70 interacted with the macrophage LXRalpha promoter, increased LXRalpha and its target mRNAs, and led to elevated levels of key proteins facilitating cholesterol efflux, including ATP-binding cassette transporters A1 and G1. Pharmacological augmentation of endogenous HSP70 in high-cholesterol diet fed zebrafish activated LXR and its target mRNAs and reduced cholesterol storage at the whole organism level. CONCLUSION: These data demonstrate that HSP70 exerts a cholesterol lowering effect in primary human cells and animals and uncover a nuclear action of HSP70 in mediating cross-talk between HSP and LXR transcriptional regulation.
Date Issued
2019-10-01
Date Acceptance
2019-07-03
Citation
Molecular Metabolism, 2019, 28, pp.135-143
ISSN
2212-8778
Publisher
Elsevier
Start Page
135
End Page
143
Journal / Book Title
Molecular Metabolism
Volume
28
Copyright Statement
© 2019 The Authors. Published by Elsevier GmbH. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/31327756
PII: S2212-8778(19)30602-7
Subjects
Cholesterol metabolism
Heat shock protein
Human macrophages
Liver X receptor
Transcriptional regulation
Animals
Cholesterol
Diet
HSP70 Heat-Shock Proteins
Humans
Leukocytes, Mononuclear
Liver X Receptors
Macrophages
Recombinant Proteins
Zebrafish
Publication Status
Published
Coverage Spatial
Germany
Date Publish Online
2020-07-06