Diabetic neuropathy affects millions globally, causing debilitating pain and sensory loss, and posing a significant challenge to healthcare systems [[2]]. now, researchers at the University of Cologne in Germany have identified a key protein, p35, that appears to impede nerve regeneration in both Type 1 and Type 2 diabetes [[3]]. Published in *Science Translational Medicine* this month, the study details a potential pathway to restore nerve function, offering a new avenue for treating this currently incurable complication and potentially preventing its progression.
Millions of people with diabetes worldwide experience nerve damage, a debilitating condition often marked by pain, numbness, and limited mobility. A key challenge in treating this complication, known as diabetic neuropathy, has been understanding why damaged nerves struggle to regenerate. Now, a new study sheds light on this process and identifies a potential therapeutic target.
Researchers at the University of Cologne in Germany have pinpointed a mechanism that explains the impaired nerve regeneration seen in diabetes. Their work, published in Science Translational Medicine in November 2025, also demonstrates a promising approach to boosting nerve repair.
Blocking a Signal to Promote Nerve Growth
The research team, led by Professor Dr. Dietmar Fischer of the Institute for Pharmacology II at the Medical Faculty of the University of Cologne and Director of the Center for Pharmacology at the Uniklinik Cologne, focused on a protein called p35. In mouse models of both Type 1 and Type 2 diabetes, they found that p35 accumulates in nerve cells. This protein then activates an enzyme that triggers a signaling cascade, effectively blocking the regrowth of nerve fibers.
By intervening in this signaling pathway – either through genetic manipulation or with newly developed small protein building blocks (peptides) delivered systemically – the scientists were able to overcome this blockade. As a result, nerve fibers grew at a rate comparable to that of healthy animals. This nerve regeneration was accompanied by significant improvements in both motor and sensory function.
A New Approach to Diabetic Nerve Healing
“Our results show for the first time that nerve healing in diabetes can be brought to a level comparable to that of healthy animals when the excessive activation of this signaling pathway is prevented,” said Professor Fischer. “Regeneration improves even when diabetic neuropathy is already established.”
The team developed and patented a peptide that directly targets the root cause of the problem and holds potential for future development as a medication. This discovery is particularly significant because the impaired nerve regeneration occurs *before* the onset of diabetic neuropathy, a common complication affecting nearly half of all patients with diabetes. Understanding this early impact could lead to preventative strategies.
Professor Fischer and his team are now investigating whether this newly discovered mechanism also directly contributes to the development of diabetic neuropathy, or if the new treatment options can reduce the risk of developing the condition. The study offers new hope for treating and potentially preventing nerve damage in diabetes, one of the most common and currently incurable complications of the disease.
Source: Universität zu Köln
Originalpublikation: Philipp Gobrecht et al.; Failure of nerve regeneration in mouse models of diabetes is caused by p35-mediated CDK5 hyperactivity; Science Translational Medicine, November 2025, DOI: 0.1126/scitranslmed.adp5849
