AT A GLANCE

A new study published in Phytomedicine reports that inflammation and gut microbiota dysfunction contributes to the pathogenesis of collagen-induced arthritis–related sarcopenia, adding that coix seed oil (CSO) may be a potential therapeutic agent.¹

“The gut microbiota composition influences the pathogenesis of sarcopenia via the ‘gut microbiota–muscle axis,’ with probiotics serving as potential therapeutic agents,” explain study authors Bai et al. “CSO, a bioactive component of Coix lacryma-jobi l., exhibits potent anti-inflammatory effects; however, its therapeutic role in rheumatoid sarcopenia (RS) and the underlying mechanisms of actions remain incompletely understood.”

In their recent study, the authors sought to uncover the efficacy of CSO in the management of RS and to elucidate its mechanisms of action at play through modulation of the gut microbiota–muscle axis to alleviate RA-related muscle atrophy.

According to the authors, ultra-performance liquid chromatography–mass spectrometry was first used to reveal the phytochemical profile of CSO. Then, a CIA rat model and C2C12 myotube assays were used to evaluate the efficacy of CSO in the alleviation of muscle atrophy. To support study analysis, gut microbiota profiling via 16S rRNA gene sequencing, muscle transcriptomic analysis, and integrative correlation analyses were completed.

According to the authors, the administration of CSO in CIA rats dose-dependently reduced their Arthritis Index (AI) scores, mitigated muscle loss, and improved grip strength while also decreasing levels of pro-inflammatory cytokines, including serum TNF-α, IL-6, and leptin, and suppressing the expression of muscle atrophy–related genes.

The authors also conducted a histological analysis, which revealed that CSO administration improved gastrocnemius pathologies by increasing type I or II fibers, fiber area or density, cross-sectional area (CSA), and satellite cell numbers, respectively.

Meanwhile, transcriptomic analysis revealed 92 downregulated genes and 72 upregulated genes in the CSO group compared to the CIA group, while 16S rRNA sequencing revealed that CSO administration successfully rebalanced the gut microbiota, with correlation analysis identifying a strong association between the alterations in gut microbiota composition and RS improvements following CSO treatment.

Through in vitro experiments, the authors also found that CSO reduced leptin-induced atrophy and JAK2–STAT3 activation in C2C12 cells.

“This study demonstrates that inflammation and gut microbiota contributes to the pathogenesis of CIA-related sarcopenia. Moreover, the gut microbiota–muscle axis and JAK/STAT signaling pathway play key roles in the regulation of muscle atrophy, suggesting that CSO may be a potential therapeutic agent,” conclude the authors.

Reference

1.     Bai Y, Zhang X, Ouyang F, et al. Coix seed oil alleviates collagen-induced arthritis-associated muscle atrophy and functional decline by modulating gut microbiota dysbiosis. Phytomedicine.2025:146:157134.