CDB25:0004173 RBP4 — TLR4

Experimentally validated in Human; Orthology-inferred in Mouse, Rat, Frog, Zebrafish, Chicken, Macaque, Pig, Dog, Cow, Chimp, Horse, Marmoset, Sheep

Title

Journal:; Year Published:

Abstract

Retinol binding protein 4 primes the NLRP3 inflammasome by signaling through Toll-like receptors 2 and 4.

Proceedings of the National Academy of Sciences of the United States of America, 2020; PubMed, Homo sapiens RBP4 — Homo sapiens TLR4
ABSTRACT: Adipose tissue (AT) inflammation contributes to systemic insulin resistance. In obesity and type 2 diabetes (T2D), retinol binding protein 4 (RBP4), the major retinol carrier in serum, is elevated in AT and has proinflammatory effects which are mediated partially through Toll-like receptor 4 (TLR4). We now show that RBP4 primes the NLRP3 inflammasome for interleukin-1β (IL1β) release, in a glucose-dependent manner, through the TLR4/MD2 receptor complex and TLR2. This impairs insulin signaling in adipocytes. IL1β is elevated in perigonadal white AT (PGWAT) of chow-fed RBP4-overexpressing mice and in serum and PGWAT of high-fat diet-fed RBP4-overexpressing mice vs. wild-type mice. Holo- or apo-RBP4 injection in wild-type mice causes insulin resistance and elevates PGWAT inflammatory markers, including IL1β. TLR4 inhibition in RBP4-overexpressing mice reduces PGWAT inflammation, including IL1β levels and improves insulin sensitivity. Thus, the proinflammatory effects of RBP4 require NLRP3-inflammasome priming. These studies may provide approaches to reduce AT inflammation and insulin resistance in obesity and diabetes.
Basic Information on RBP4
Ligand Name: retinol binding protein 4
Other Symbols: N/A
Ligand Location: secreted based on perplexity, uniprot
HGNC Gene Symbol Report: RBP4
GeneCards: RBP4
Interactions with other Receptors for RBP4
Basic Information on TLR4
Receptor Name: toll like receptor 4
Other Symbols: hToll, CD284, TLR-4, ARMD10
Receptor Location: cell membrane based on hpa, perplexity, uniprot
HGNC Gene Symbol Report: TLR4
GeneCards: TLR4