Go to The Journal of Clinical Investigation
  • About
  • Editors
  • Consulting Editors
  • For authors
  • Publication ethics
  • Publication alerts by email
  • Transfers
  • Advertising
  • Job board
  • Contact
  • Physician-Scientist Development
  • Current issue
  • Past issues
  • By specialty
    • COVID-19
    • Cardiology
    • Immunology
    • Metabolism
    • Nephrology
    • Oncology
    • Pulmonology
    • All ...
  • Videos
  • Collections
    • In-Press Preview
    • Resource and Technical Advances
    • Clinical Research and Public Health
    • Research Letters
    • Editorials
    • Perspectives
    • Physician-Scientist Development
    • Reviews
    • Top read articles

  • Current issue
  • Past issues
  • Specialties
  • In-Press Preview
  • Resource and Technical Advances
  • Clinical Research and Public Health
  • Research Letters
  • Editorials
  • Perspectives
  • Physician-Scientist Development
  • Reviews
  • Top read articles
  • About
  • Editors
  • Consulting Editors
  • For authors
  • Publication ethics
  • Publication alerts by email
  • Transfers
  • Advertising
  • Job board
  • Contact

Usage Information

Macrophage-derived Spp1 promotes intramuscular fat in dystrophic muscle
Philip K. Farahat, … , S. Armando Villalta, Melissa J. Spencer
Philip K. Farahat, … , S. Armando Villalta, Melissa J. Spencer
Published July 8, 2025
Citation Information: JCI Insight. 2025;10(13):e181946. https://doi.org/10.1172/jci.insight.181946.
View: Text | PDF
Research Article Genetics Muscle biology

Macrophage-derived Spp1 promotes intramuscular fat in dystrophic muscle

  • Text
  • PDF
Abstract

Duchenne muscular dystrophy (DMD) is a progressive muscle wasting disorder involving cycles of muscle degeneration and regeneration, leading to accumulation of intramuscular fibrosis and fat. Ablation of Osteopontin/Spp1 in a murine model of DMD (mdx) improves the dystrophic phenotype, but the source of Spp1 and its impact on target cells in dystrophic muscles remain unknown. In dystrophic muscles, macrophages are the predominate infiltrating leukocyte and express high levels of Spp1. We used macrophage-specific ablation combined with single-cell transcriptional profiling to uncover the impact of macrophage-derived Spp1 on cell-cell interactions in mdx muscles. Ablation of macrophage-specific Spp1 (cKO) correlated with reduction of 2 PDGFRa+ stromal cell populations, expressing Lifr+ and Procr+. Sorting and transcriptional profiling of these populations confirmed that they are enriched in adipogenesis genes and are highly related to fibroadipogenic precursors (FAPS). These adipogenic stromal cells (ASC) displayed more adipogenic potential in vitro compared with FAPS, likely due to a more differentiated state. Reduction of ASCs correlated with reduced intramuscular diaphragmatic fat and improved diaphragm function. These data suggest a role for myeloid-derived Spp1 in the differentiation of stromal cells towards an adipogenic fate, leading to accumulation of intramuscular fat in dystrophic muscles.

Authors

Philip K. Farahat, Chino Kumagai-Cresse, Raquel L. Aragón, Feiyang Ma, Justin K. Amakor, Alejandro Espinoza, Irina Kramerova, Robert J. Jimenez, Bradley M. Smith, Jesus Perez, Rachelle H. Crosbie, Apoorva H. Nagendra, Jackie McCourt-Towner, Gerald Coulis, Oluwatayo F. Ikotun, April D. Pyle, Matteo Pellegrini, Elizabeth M. McNally, S. Armando Villalta, Melissa J. Spencer

×

Usage data is cumulative from July 2025 through December 2025.

Usage JCI PMC
Text version 2,093 309
PDF 469 52
Figure 330 6
Supplemental data 80 12
Citation downloads 77 0
Totals 3,049 379
Total Views 3,428

Usage information is collected from two different sources: this site (JCI) and Pubmed Central (PMC). JCI information (compiled daily) shows human readership based on methods we employ to screen out robotic usage. PMC information (aggregated monthly) is also similarly screened of robotic usage.

Various methods are used to distinguish robotic usage. For example, Google automatically scans articles to add to its search index and identifies itself as robotic; other services might not clearly identify themselves as robotic, or they are new or unknown as robotic. Because this activity can be misinterpreted as human readership, data may be re-processed periodically to reflect an improved understanding of robotic activity. Because of these factors, readers should consider usage information illustrative but subject to change.

Advertisement

Copyright © 2025 American Society for Clinical Investigation
ISSN 2379-3708

Sign up for email alerts