Current research in microbial sciencesFeb 16, 2026

Daily body clocks control bone cell renewal by increasing specific immune cells through gut bacteria

Circadian Biology Weekly Brief ↗PubMed ↗DOI ↗

Updated Jun 27, 2026

Abstract

Essence

Circadian-misaligned feeding in male mice was linked to bone loss through a gut microbiota-Th17-osteomorph pathway.

Evidence

This animal study used long-term rest-phase time-restricted feeding and fecal microbiota transplantation into germ-free mice to test microbiome, immune-cell, osteoclast-recycling, and bone changes.

Caveat

Findings come from male mouse and germ-free recipient models, so human relevance, sex differences, and real-world feeding disruption remain unresolved.

Simplified

The circadian clock coordinates diverse biological processes to maintain physiological function and homeostasis in mammals under the day-night light cycle. Disruption of circadian rhythms impairs immune and metabolic functions and increases susceptibility to various diseases. Here, we demonstrate that long-term rest-phase time-restricted feeding (TRF), which disrupts circadian rhythmicity, induces bone loss and gut microbiota dysbiosis in male mice. Fecal microbiota transplantation (FMT) from circadian-misaligned feeding donors to germ-free recipients increased Th17 cell populations, thereby promoting the fusion of osteomorphs-a recently identified osteoclast precursor-into mature osteoclasts through the RANKL-RANK-OPG signaling pathway. Collectively, our findings identify a gut microbiota-Th17-osteomorph axis as a critical mediator of circadian disruption-induced bone loss, uncovering a previously unrecognized mechanism by which circadian rhythms regulate skeletal homeostasis.