An early diagnostic tool for diabetic peripheral neuropathy in rats

PLoS One. 2015 May 18;10(5):e0126892. doi: 10.1371/journal.pone.0126892. eCollection 2015.

Abstract

The skin's rewarming rate of diabetic patients is used as a diagnostic tool for early diagnosis of diabetic neuropathy. At present, the relationship between microvascular changes in the skin and diabetic neuropathy is unclear in streptozotocin (STZ) diabetic rats. The aim of this study was to investigate whether the skin rewarming rate in diabetic rats is related to microvascular changes and whether this is accompanied by changes observed in classical diagnostic methods for diabetic peripheral neuropathy. Computer-assisted infrared thermography was used to assess the rewarming rate after cold exposure on the plantar skin of STZ diabetic rats' hind paws. Peripheral neuropathy was determined by the density of intra-epidermal nerve fibers (IENFs), mechanical sensitivity, and electrophysiological recordings. Data were obtained in diabetic rats at four, six, and eight weeks after the induction of diabetes and in controls. Four weeks after the induction of diabetes, a delayed rewarming rate, decreased skin blood flow and decreased density of IENFs were observed. However, the mechanical hyposensitivity and decreased motor nerve conduction velocity (MNCV) developed 6 and 8 weeks after the induction of diabetes. Our study shows that the skin rewarming rate is related to microvascular changes in diabetic rats. Moreover, the skin rewarming rate is a non-invasive method that provides more information for an earlier diagnosis of peripheral neuropathy than the classical monofilament test and MNCV in STZ induced diabetic rats.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood Glucose / metabolism
  • Body Weight
  • Cold Temperature
  • Diabetic Neuropathies / blood
  • Diabetic Neuropathies / diagnosis*
  • Diabetic Neuropathies / physiopathology
  • Electrophysiological Phenomena
  • Epidermis / innervation
  • Epidermis / pathology
  • Epidermis / physiopathology
  • Female
  • Microvessels / pathology
  • Microvessels / physiopathology
  • Oxygen / metabolism
  • Pancreas / pathology
  • Peripheral Nervous System Diseases / blood
  • Peripheral Nervous System Diseases / diagnosis*
  • Peripheral Nervous System Diseases / physiopathology
  • Platelet Endothelial Cell Adhesion Molecule-1 / metabolism
  • Rats
  • Regional Blood Flow
  • Skin Temperature

Substances

  • Blood Glucose
  • Platelet Endothelial Cell Adhesion Molecule-1
  • Oxygen

Grants and funding

This work was supported by Nuts Ohra: 1201-054. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.