Osteoarthritis is a leading cause of performance failure in horses as well as having an impact on quality of life. Researchers continually seek new advancements in this field to provide therapeutic and palliative relief from chronic joint pain. A new development might hold promise for future therapeutic options: use of scorpion venom [Cook-Sangar, M.L., et al., “A potent peptide-steroid conjugate accumulates in cartilage and reverses arthritis without evidence of systemic corticosteroid exposure.” Science Translational Medicine, doi:10.1126/scitranslmed.aay1041, 2020].
A recent study revealed that coupling scorpion venom peptides with a corticosteroid such as triamcinolone and administering this product systemically is able to alleviate inflammation in mice joint cartilage. The researchers identified cysteine-dense peptides (CDPs, which are mini-proteins obtained from scorpion venom) that accumulate in joints within 30 minutes following systemic administration yet remain in the cartilage for more than four days. Combining the CDP with the desired drug—in this case triamcinolone—makes it possible to treat only the desired tissue, i.e., cartilage.
This peptide delivery system provides targeted local delivery of the anti-inflammatory drug to cartilage without causing systemic toxicity. The other benefit is that treatment occurs in multiple joints with systemic administration. The researchers are hopeful that it might be possible to use this targeted CDP treatment to deliver other drugs to damaged cartilage to not just control arthritis, but to reverse it.