Morphometric changes in sympathetic nerve fibres in diabetes

Area of Science:

• Nerve regeneration and neuropathology
• Vascular disease research
• Diabetes mellitus complications

Background:

• Arteriosclerosis obliterans (ASO) affects peripheral arteries, potentially impacting nerve function.
• Diabetic neuropathy is a common complication, but specific changes in sympathetic nerve fibers require further investigation.
• Morphometric analysis provides quantitative data on nerve fiber structure.

Purpose of the Study:

• To investigate morphometric changes in lumbar sympathetic nerve fibers in patients with arteriosclerosis obliterans.
• To compare nerve fiber characteristics between diabetic, glucose-intolerant, and non-diabetic individuals with ASO.
• To identify structural alterations in unmyelinated axons and endoneurial space.

Main Methods:

• Electron microscopy of lumbar sympathetic nerve fibers from 12 ASO patients.
• Morphometric analysis of nerve fiber cross-sections.
• Quantification of percent area fraction for unmyelinated axons and endoneurial space.

Main Results:

• A significant decrease in the percent area fraction of unmyelinated axons was observed in diabetic and glucose-intolerant patients.
• A significant increase in the percent area fraction of the endoneurial space was demonstrated in these patient groups.
• These changes suggest structural alterations in sympathetic nerve fibers associated with impaired glucose metabolism.

Conclusions:

• Diabetes and glucose intolerance are associated with reduced unmyelinated axon density and increased endoneurial space in lumbar sympathetic nerves.
• These findings may contribute to understanding the pathophysiology of autonomic dysfunction in diabetic ASO.
• Further research is warranted to explore the functional implications of these morphometric changes.