C-Peptide replacement therapy and sensory nerve function in type 1 diabetic neuropathy

Diabetes Care. 2007 Jan;30(1):71-6. doi: 10.2337/dc06-1274.

Abstract

Objective: C-peptide replacement in animals results in amelioration of diabetes-induced functional and structural abnormalities in peripheral nerves. The present study was undertaken to examine whether C-peptide administration to patients with type 1 diabetes and peripheral neuropathy improves sensory nerve function.

Research design and methods: This was an exploratory, double-blinded, randomized, and placebo-controlled study with three study groups that was carried out at five centers in Sweden. C-peptide was given as a replacement dose (1.5 mg/day, divided into four subcutaneous doses) or a dose three times higher (4.5 mg/day) during 6 months. Neurological examination and neurophysiological measurements were performed before and after 6 months of treatment with C-peptide or placebo.

Results: The age of the 139 patients who completed the protocol was 44.2 +/- 0.6 (mean +/- SE) years and their duration of diabetes was 30.6 +/- 0.8 years. Clinical neurological impairment (NIA) (score >7 points) of the lower extremities was present in 86% of the patients at baseline. Sensory nerve conduction velocity (SCV) was 2.6 +/- 0.08 SD below body height-corrected normal values at baseline and improved similarly within the two C-peptide groups (P < 0.007). The number of patients responding with a SCV peak potential improvement >1.0 m/s was greater in C-peptide-treated patients than in those receiving placebo (P < 0.03). In the least severely affected patients (SCV < 2.5 SD below normal at baseline, n = 70) SCV improved by 1.0 m/s (P < 0.014 vs. placebo). NIA score and vibration perception both improved within the C-peptide-treated groups (P < 0.011 and P < 0.002). A1C levels (7.6 +/- 0.1% at baseline) decreased slightly but similarly in C-peptide-and placebo-treated patients during the study.

Conclusions: C-peptide treatment for 6 months improves sensory nerve function in early-stage type 1 diabetic neuropathy.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Age of Onset
  • C-Peptide / therapeutic use*
  • Diabetes Mellitus, Type 1 / complications*
  • Diabetic Neuropathies / drug therapy*
  • Diabetic Neuropathies / physiopathology*
  • Double-Blind Method
  • Humans
  • Middle Aged
  • Neural Conduction / physiology*
  • Neurologic Examination
  • Patient Selection
  • Sural Nerve / physiopathology
  • Sweden

Substances

  • C-Peptide