Angiopoietin-like 4 is over-expressed in rheumatoid arthritis patients: association with pathological bone resorption

Introduction Osteoclasts are responsible for the bone loss associated with rheumatoid arthritis (RA). The secreted adipokine angiopoietin-like 4 (ANGPTL4) specifically increases osteoclast-mediated bone resorption. We have investigated expression of ANGPTL4 and its regulatory transcription factor, h...

Full description

Bibliographic Details
Main Authors: Swales, C, Athanasou, N, Knowles, H
Format: Journal article
Language:English
Published: Public Library of Science 2014
_version_ 1797068103641726976
author Swales, C
Athanasou, N
Knowles, H
author_facet Swales, C
Athanasou, N
Knowles, H
author_sort Swales, C
collection OXFORD
description Introduction Osteoclasts are responsible for the bone loss associated with rheumatoid arthritis (RA). The secreted adipokine angiopoietin-like 4 (ANGPTL4) specifically increases osteoclast-mediated bone resorption. We have investigated expression of ANGPTL4 and its regulatory transcription factor, hypoxia-inducible factor-1 alpha (HIF-1α), in osteoclasts and other cells within rheumatoid synovium. We have also examined whether circulating levels of ANGPTL4 differ in RA patients compared with that in normal controls or patients with osteoarthritis (OA). Results Immunohistochemical analysis revealed that bone-apposing osteoclasts within the rheumatoid synovium express both ANGPTL4 and HIF-1α. ANGPTL4 was also strongly expressed in synovial lining cells, endothelial cells, stromal cells, CD68+ macrophages and plasma cells within RA synovium. Little ANGPTL4 was evident in normal synovial tissue. This reflected the over-expression of HIF-1α in rheumatoid versus normal synovial tissue. The concentration of ANGPTL4 was higher in both the serum and the synovial fluid of RA patients than in patients with OA or normal controls. High serum ANGPTL4 associated with elevated levels of the serum marker of bone resorption, receptor activator for nuclear factor κB ligand (RANKL). Conclusions Over-expression of ANGPTL4 in multiple cell types within the rheumatoid synovium potentially provides a local pool of ANGPTL4 to stimulate osteoclast-mediated bone resorption in RA. Additionally, correlation of high serum ANGPTL4 with circulating RANKL suggests that ANGPTL4 may represent a novel marker for bone destruction in RA.
first_indexed 2024-03-06T22:05:51Z
format Journal article
id oxford-uuid:501d1451-aa40-4c82-92ff-608460eeda48
institution University of Oxford
language English
last_indexed 2024-03-06T22:05:51Z
publishDate 2014
publisher Public Library of Science
record_format dspace
spelling oxford-uuid:501d1451-aa40-4c82-92ff-608460eeda482022-03-26T16:11:42ZAngiopoietin-like 4 is over-expressed in rheumatoid arthritis patients: association with pathological bone resorptionJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:501d1451-aa40-4c82-92ff-608460eeda48EnglishSymplectic Elements at OxfordPublic Library of Science2014Swales, CAthanasou, NKnowles, HIntroduction Osteoclasts are responsible for the bone loss associated with rheumatoid arthritis (RA). The secreted adipokine angiopoietin-like 4 (ANGPTL4) specifically increases osteoclast-mediated bone resorption. We have investigated expression of ANGPTL4 and its regulatory transcription factor, hypoxia-inducible factor-1 alpha (HIF-1α), in osteoclasts and other cells within rheumatoid synovium. We have also examined whether circulating levels of ANGPTL4 differ in RA patients compared with that in normal controls or patients with osteoarthritis (OA). Results Immunohistochemical analysis revealed that bone-apposing osteoclasts within the rheumatoid synovium express both ANGPTL4 and HIF-1α. ANGPTL4 was also strongly expressed in synovial lining cells, endothelial cells, stromal cells, CD68+ macrophages and plasma cells within RA synovium. Little ANGPTL4 was evident in normal synovial tissue. This reflected the over-expression of HIF-1α in rheumatoid versus normal synovial tissue. The concentration of ANGPTL4 was higher in both the serum and the synovial fluid of RA patients than in patients with OA or normal controls. High serum ANGPTL4 associated with elevated levels of the serum marker of bone resorption, receptor activator for nuclear factor κB ligand (RANKL). Conclusions Over-expression of ANGPTL4 in multiple cell types within the rheumatoid synovium potentially provides a local pool of ANGPTL4 to stimulate osteoclast-mediated bone resorption in RA. Additionally, correlation of high serum ANGPTL4 with circulating RANKL suggests that ANGPTL4 may represent a novel marker for bone destruction in RA.
spellingShingle Swales, C
Athanasou, N
Knowles, H
Angiopoietin-like 4 is over-expressed in rheumatoid arthritis patients: association with pathological bone resorption
title Angiopoietin-like 4 is over-expressed in rheumatoid arthritis patients: association with pathological bone resorption
title_full Angiopoietin-like 4 is over-expressed in rheumatoid arthritis patients: association with pathological bone resorption
title_fullStr Angiopoietin-like 4 is over-expressed in rheumatoid arthritis patients: association with pathological bone resorption
title_full_unstemmed Angiopoietin-like 4 is over-expressed in rheumatoid arthritis patients: association with pathological bone resorption
title_short Angiopoietin-like 4 is over-expressed in rheumatoid arthritis patients: association with pathological bone resorption
title_sort angiopoietin like 4 is over expressed in rheumatoid arthritis patients association with pathological bone resorption
work_keys_str_mv AT swalesc angiopoietinlike4isoverexpressedinrheumatoidarthritispatientsassociationwithpathologicalboneresorption
AT athanasoun angiopoietinlike4isoverexpressedinrheumatoidarthritispatientsassociationwithpathologicalboneresorption
AT knowlesh angiopoietinlike4isoverexpressedinrheumatoidarthritispatientsassociationwithpathologicalboneresorption