Background & Aims
Diabetic peripheral neuropathy (DPN) is a common complication of diabetes, affecting up to 50% of patients. It involves the gradual loss of small peripheral nerve fibers, leading to severe consequences like neuropathic pain and potential amputations. Despite its prevalence and impact, the underlying mechanisms of DPN remain poorly understood. Treatments for sensory loss and neuropathic pain are limited, often resulting in serious cases necessitating amputation. While decreased intraepidermal nerve fiber density is a diagnostic marker, it doesn’t explain why some people development pain and others don’t. The pursuit of effective treatments for DPN primarily centers around dissecting neural pathophysiology. However, nerve fibers and their myelin, produced by Schwann cells, share a symbiotic relationship in both location and function. Integrating them into a cohesive functional unit (glia-neural unit) is vital for comprehending neural damage mechanisms and informing future DPN treatments.
Methods
We firstly visualize and quantify the structures of cutaneous nerve fibres and Schwann cells in three study groups: participants with painful DPN, participants with painless DPN and healthy controls. Using immunohistochemistry, nerve fibres will be labelled by PGPP9.5 antibody and Schwann cell will be labelled by S100b antibody. Then confocal microscope will be used to acquire the labelled signals and data will be analyzed by stereological methods in captured confocal images. The comprehensive quantifications include: intraepidermal nerve fibre density, subepidermal nerve fibre density, subepidermal Schwann cell soma density and subepidermal Schwann cell projection density. We then study the correlations between the glia-neural structures changes and the clinical manifestations.
Results
Preliminary results showed significant decrease in both peripheral nerve fibres and Schwann cell projections in participant with diabetic polyneuropathy, but no significant difference in Schwann cell number density was found between studies group. The correlation analysis between glia-neural structures and clinical manifestations are still ongoing, but results will be presented in the meeting.
Conclusions
There is significant decrease in glia-neural structures in people with Diabetic polyneuropathy. But Schwann cell is very plastic, with significant damages found in Schwann cell projections in diabetic polyneuropathy, the Schwann cell number remains no significant change.
References
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Presenting Author
Xiaoli Hu
Poster Authors
Xiaoli Hu
PhD
Aarhus University
Lead Author
Topics
- Specific Pain Conditions/Pain in Specific Populations: Neuropathic Pain - Peripheral