Intermittent fasting relieved osteoarthritis in mice by reducing excess neuropeptide Y secretion from bone cells, which was driving joint inflammation.
New mechanism discoveredOsteocyte-derived neuropeptide Y was identified for the first time as a driver of osteoarthritis inflammation, bone destruction, and nerve growth
What the researchers found
Osteocytes (the most common bone cells) secreted excess neuropeptide Y during osteoarthritis. This NPY promoted inflammation, osteoclast formation (cells that break down bone), and neurite outgrowth (nerve growth that contributes to pain).
Intermittent fasting reversed these effects. Culture medium from osteocytes of fasting mice did not trigger the same inflammatory and bone-destroying responses. When researchers genetically deleted NPY from osteocytes, intermittent fasting lost its beneficial effects on osteoarthritis. This proved that osteocyte NPY is the specific target through which fasting works.
The findings held in both surgically induced osteoarthritis (meniscus destabilization) and natural aging-induced osteoarthritis.
Why it matters
Osteoarthritis affects over 500 million people worldwide with no disease-modifying treatment. Intermittent fasting has shown health benefits in many contexts, but the mechanism for joint protection was unknown. This study identifies a specific molecular pathway: osteocyte NPY. This could lead to targeted drug development for osteoarthritis.
The numbers in context
- Excess NPY secreted by osteocytes during osteoarthritis
- NPY promoted pro-inflammatory, pro-osteoclastic, and pro-neurite outgrowth effects
- Intermittent fasting reversed these effects
- Osteocyte NPY knockout abolished fasting benefits
- Effective in both surgical (DMM) and aging-induced OA models
How the study worked
Researchers used two mouse osteoarthritis models: surgically induced (destabilization of the medial meniscus, DMM) and natural aging. They tested intermittent fasting in both models. They measured NPY levels, inflammation markers, osteoclast formation, and nerve outgrowth. They used osteocyte-specific NPY knockout mice to confirm the mechanism. Cell culture experiments with osteocyte-conditioned medium tested the direct effects of NPY.
Who was studied
Mice with surgically induced or aging-related osteoarthritis, including osteocyte NPY knockout mice
What this study cannot tell us
This was tested in mice, not people. Mouse osteoarthritis models do not perfectly replicate the decades-long progression of human osteoarthritis. The specific intermittent fasting protocol may not translate directly to human practice. The osteocyte NPY knockout was a genetic deletion, not a drug intervention. Whether blocking NPY pharmacologically would have the same effect is unknown.
How to read the evidence
Rated preliminary: strong mechanistic animal study using both surgical and aging models plus genetic confirmation, but entirely in mice.
When this study was published
Published in 2024. This is a new mechanistic discovery linking NPY, bone cells, and osteoarthritis.
The bigger picture
Osteoarthritis affects over 500 million people with no disease-modifying treatment. This discovery of the NPY-osteocyte connection provides a new therapeutic target and a mechanistic explanation for why intermittent fasting may help joint health.
Questions still open
- Would NPY-blocking drugs replicate the fasting benefit without dietary changes?
- Does this mechanism operate in human osteoarthritis?
Common questions
Can intermittent fasting help osteoarthritis?
What is neuropeptide Y's role in osteoarthritis?
Read the original research
Intermittent Fasting Targets Osteocyte Neuropeptide Y to Relieve Osteoarthritis.
Advanced science (Weinheim, Baden-Wurttemberg, Germany), 11(34), e2400196
Citation
Qian, Yu-Xuan; Rao, Shan-Shan; Tan, Yi-Juan; Wang, Zun; Yin, Hao; Wan, Teng-Fei; He, Ze-Hui; Wang, Xin; Hong, Chun-Gu; Zeng, Hai-Jin; Luo, Yi; Duan, Yan-Xin; Zhu, Hao; Hu, Xin-Yue; Zou, Ling; Zhang, Yan; Liu, Bing-Bing; Wang, Zhen-Xing; Du, Wei; Chen, Chun-Yuan; Xie, Hui. (2024). Intermittent Fasting Targets Osteocyte Neuropeptide Y to Relieve Osteoarthritis.. Advanced science (Weinheim, Baden-Wurttemberg, Germany), 11(34), e2400196. https://doi.org/10.1002/advs.202400196