Palovarotene reduces heterotopic ossification in juvenile FOP mice but exhibits pronounced skeletal toxicity

eLife

Masakazu Yamamoto¹  Sarah-Anne E Nicholas¹  Michael J Schneider¹  Sean J Stoessel¹  Parvathi M Devarakonda¹  David J Goldhamer¹  John B Lees-Shepard¹ 

[1] Department of Molecular and Cell Biology, University of Connecticut Stem Cell Institute, University of Connecticut, Storrs, United States;

关键词: fibrodysplasia ossificans progressiva;    palovarotene;    fibro/adipogenic progenitor;    heterotopic ossification;    activin A;    ACVR1;   

DOI  :  10.7554/eLife.40814

来源: DOAJ

【 摘 要 】

Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disorder characterized by debilitating heterotopic ossification (HO). The retinoic acid receptor gamma agonist, palovarotene, and antibody-mediated activin A blockade have entered human clinical trials, but how these therapeutic modalities affect the behavior of pathogenic fibro/adipogenic progenitors (FAPs) is unclear. Using live-animal luminescence imaging, we show that transplanted pathogenic FAPs undergo rapid initial expansion, with peak number strongly correlating with HO severity. Palovarotene significantly reduced expansion of pathogenic FAPs, but was less effective than activin A inhibition, which restored wild-type population growth dynamics to FAPs. Palovarotene pretreatment did not reduce FAPs’ skeletogenic potential, indicating that efficacy requires chronic administration. Although palovarotene inhibited chondrogenic differentiation in vitro and reduced HO in juvenile FOP mice, daily dosing resulted in aggressive synovial joint overgrowth and long bone growth plate ablation. These results highlight the challenge of inhibiting pathological bone formation prior to skeletal maturation.

【 授权许可】

Unknown