Contrary to what was previously believed, new research demonstrates that proinsulin C-peptide has significant physiological effects and exhibits the traits of a bioactive peptide. Studies in type1 diabetes, both in humans and in animal models, show that replacement amounts of C-peptide can enhance peripheral nerve function and delay or reverse the onset of aberrant nerve anatomical changes. C-peptide replacement improves peripheral nerve function in diabetes type 1 patients with early-stage neuropathy as measured by sensory nerve conduction velocity and quantitative sensory testing. Similar to this, autonomic nerve dysfunction is improved after receiving C peptide for up to three months. The mechanisms of action are related to the capacity of C-peptide to reverse diabetes-induced reductions in endoneurial blood flow, in -ATPase activity, and in the modulation of neurotropic factors. This has been evaluated in animal models of type1 diabetes, and the improved nerve function is accompanied by reversal or prevention of nerve structural changes. The results put together show that C-peptide might be a novel option for treating neuropathy in type 1 diabetes.
Autonomic neuropathy; Diabetic peripheral neuropathy; Painful diabetic neuropathy; Bioactive peptide
