Researchers reported on Mar. 30 that a molecule called artemin may serve as both a marker of disease and a potential therapeutic target in cats with degenerative joint disease, the main form of which is osteoarthritis. The study found that elevated levels of artemin could indicate the presence of the disease, providing new insights into how pain is generated in cats.
This research matters because understanding the mechanisms behind chronic pain in cats could lead to better treatments for feline osteoarthritis, a condition affecting many animals and humans. Currently, options for managing chronic pain in cats are limited.
The study compared known osteoarthritis pain pathways from dogs and humans to those present in cats with degenerative joint disease. Researchers focused on transient receptor potential (TRP) ion channels found in spinal cord neurons, which can be activated by artemin binding to its receptor GFRA-3. This activation triggers processes involved in registering pain.
"We know that Artemin/GFRA-3 induced changes to TRP channels play a role in osteoarthritis pain in humans and dogs, but didn't know whether cats shared this biological pathway," said Santosh Mishra, associate professor of neurobiology at North Carolina State University and co-corresponding author of the study.
Duncan Lascelles, professor of translational pain research at NC State and co-corresponding author, said: "With relatively limited options for managing chronic pain in cats, if we can understand more about how the sensation of pain is being generated in cats themselves, then we will be a step closer to developing therapies that are effective in cats."
The interdisciplinary team assessed over 70 cats for DJD status and collected blood serum and dorsal root ganglia tissue samples from both healthy animals and those with DJD. They confirmed that TRP channels associated with osteoarthritis were present and functional even before disease onset but found increased artemin concentrations only correlated with X-ray evidence of DJD rather than veterinarian-assessed pain.
Mishra said: "We saw that artemin levels were increased in cats with radiographic evidence of the disease, but that artemin levels didn't correlate to veterinarian-assessed pain. However, knowing how difficult it is to measure pain in cats, in future work we will utilize technology to more objectively measure pain." He added: "If veterinarians could do a blood test for increased artemin to diagnose DJD instead of X-rays it would save time and stress for cats. And perhaps targeting artemin expression could be therapy for either pain or disease progression. Now that we know the pathway is conserved, we can dig deeper into the mechanisms to find therapies."
Lascelles concluded: "Because cats exhibit naturally occurring DJD/OA similar to people, this work provides a valuable window into real biological processes and pain mechanisms which will ultimately improve clinical care for cats. The findings may also help refine translational models and inspire cross‑species therapeutic advances."
