A hormone traditionally used to treat bone loss may hold the key to stopping at its source, according to a new study.
Chronic back pain is often linked to the deterioration of spinal discs and vertebral end plates, which are the thin layers of tissue separating the discs from the vertebrae, according to medical sources.
When these break down, they become porous, allowing nerves that aren’t usually impacted to enter the spinal center, leading to frequent discomfort.
Research led by Dr. Janet L. Crane at Johns Hopkins University found that parathyroid hormone (PTH) could prevent and even reverse the growth of pain-sensing nerves into damaged areas of the spine.
naturally produce PTH, which experts say plays a key role in regulating calcium levels and bone remodeling.
These findings could shift the focus of from managing symptoms to modifying the underlying issue, according to scientists.
"During spinal degeneration, pain-sensing nerves grow into regions where they normally do not exist. Our findings show that parathyroid hormone can reverse this process by activating natural signals that push these nerves away," Crane said in a press release.
Synthetic versions of PTH are already used to treat osteoporosis. Earlier research hinted that these treatments might also reduce bone-related pain, but the underlying was not well-understood.
Using animal models, the Johns Hopkins researchers found that one to two months of PTH treatment led to denser, more stable vertebral endplates.
More significantly, the treatment triggered bone-building cells, known as osteoblasts, to produce a protein called Slit3, the study detailed.
The study found that this protein repels growing nerve fibers, preventing them from infiltrating sensitive regions of the spine.
When the researchers removed Slit3 from the mice, the hormone's pain-relieving effects disappeared, confirming the protein's critical role in the process.
PTH is by the Food and Drug Administration to treat osteoporosis. Some patients receiving the hormone for bone density have reported unexpected relief from back pain, a phenomenon this study could help explain.
"Our study suggests that PTH treatment of [lower back pain] during spinal degeneration may reduce aberrant innervation (abnormal nerve growth)," Crane concluded.
The doctor said this research lays the foundation for future clinical trials that will explore PTH's effectiveness as a disease-modifying and for spinal degeneration.
Researchers noted several limitations, including the possibility that PTH treatment could affect the in ways not fully explored in this study.
Because the study focused specifically on the Slit3 protein, further research is needed to determine how other genetic factors and bone-forming processes might influence spinal nerve growth and pain relief.
The study was published in the journal Bone Research.