Reduced osteoprotegerin expression by osteocytes may contribute to rebound resorption after denosumab discontinuation

Denosumab is an anti-RANKL Ab that potently suppresses bone resorption, increases bone mass, and reduces fracture risk. Discontinuation of denosumab causes rapid rebound bone resorption and bone loss, but the molecular mechanisms are unclear. We generated humanized RANKL mice and treated them with denosumab to examine the cellular and molecular conditions associated with rebound resorption. Denosumab potently suppressed both osteoclast and osteoblast numbers in cancellous bone in humanized RANKL mice. The decrease in osteoclast number was not associated with changes in osteoclast progenitors in bone marrow. Long-term, but not short-term, denosumab administration reduced osteoprotegerin (OPG) mRNA in bone. Localization of OPG expression revealed that OPG mRNA is produced by a subpopulation of osteocytes. Long-term denosumab administration reduced osteocyte OPG mRNA, suggesting that OPG expression declines as osteocytes age. Consistent with this, osteocyte expression of OPG was more prevalent near the surface of cortical bone in humans and mice. These results suggest that new osteocytes are an important source of OPG in remodeling bone and that suppression of remodeling reduces OPG abundance by reducing new osteocyte formation. The lack of new osteocytes and the OPG they produce may contribute to rebound resorption after denosumab discontinuation.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:8

Enthalten in:

JCI insight - 8(2023), 18 vom: 22. Sept.

Sprache:

Englisch

Beteiligte Personen:

Fu, Qiang [VerfasserIn]
Bustamante-Gomez, Nancy C [VerfasserIn]
Reyes-Pardo, Humberto [VerfasserIn]
Gubrij, Igor [VerfasserIn]
Escalona-Vargas, Diana [VerfasserIn]
Thostenson, Jeff D [VerfasserIn]
Palmieri, Michela [VerfasserIn]
Goellner, Joseph J [VerfasserIn]
Nookaew, Intawat [VerfasserIn]
Barnes, C Lowry [VerfasserIn]
Stambough, Jeffrey B [VerfasserIn]
Ambrogini, Elena [VerfasserIn]
O'Brien, Charles A [VerfasserIn]

Links:

Volltext

Themen:

4EQZ6YO2HI
Bone Biology
Denosumab
Journal Article
Osteoclast/osteoblast biology
Osteoprotegerin
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

Anmerkungen:

Date Completed 25.09.2023

Date Revised 25.10.2023

published: Electronic

Citation Status MEDLINE

doi:

10.1172/jci.insight.167790

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM360812481