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Abstracts of the 8th Meeting of the Italian Peripheral Nerve Study Group: 4
Author(s) -
Nolano M,
Provitera V,
Stancanelli A,
Saltalamacchia AM,
Crisci C,
Santoro L
Publication year - 2003
Publication title -
journal of the peripheral nervous system
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1
H-Index - 67
eISSN - 1529-8027
pISSN - 1085-9489
DOI - 10.1046/j.1529-8027.2003.00004.x
Subject(s) - skin biopsy , blisters , medicine , nerve fiber , pathology , biopsy , cutaneous nerve , anatomy , ataxia , epidermis (zoology) , psychiatry , immunology
A severe sensory neuropathy, mostly involving large myelinated sensory fibers, characterizes Friedreich ataxia since the early onset. Recently, an involvement of unmyelinated nerve fibers has been observed studying cutaneous innervation by means of immunohistochemical techniques and confocal microscopy. Quantification of epidermal nerve fibers (ENFs) by skin biopsy has been extensively used in the last decade to evaluate small‐fiber neuropathies. This minimally invasive procedure, repeatable over time, allows to monitor a neuropathic process. An even less invasive technique is the biopsy of the only epidermis, obtained removing the roof of suction skin blister, sparing basal membrane and vessels. Skin blister, beside a diagnostic tool in sensory neuropathies, is a wound model to study nerve regeneration in human epidermis. The aim of our research was to define the regenerative capability of cutaneous nerve fibers in patients affected by Friedreich's ataxia evaluating time‐course and patterns of nerve fibers regeneration. Six patients (4F, 2M, age 19–34) affected by genetically determined Friedreich ataxia were included in our study. In each subject we induced 5 couples of 2 mm blisters on the forearm. At different time points (1–2–3–4 weeks after blister induction) one blister was removed by 3 mm punch skin biopsy and one was reblistered (3‐mm blister) and the roof removed. The larger size of these biopsies and blisters allowed at including normal skin immediately adjacent to the blister wound. Epidermal nerve fibers were visualised using antibodies to the pan‐neuronal marker protein gene product 9.5 (PGP 9.5) on frozen sections from skin biopsies and on the whole blister roofs. Quantification of ENFs was performed on skin sections using digitised images acquired by confocal microscopy (CARV) and Neurolucida software. Blister allowed to have a panoramic and global view of the regenerative process especially of the collateral extension of axons from adjacent normal epidermis, while biopsy allowed to observe the sprouting from the subepidermal neural plexus. Both these phenomena resulted markedly evident in all FA subjects indicating a normal capability of nerve fibers to regenerate. Blister wound probably induces the release of nerve growth factors stimulating nerve regeneration as in normal subjects. At least for the short period of observation (four weeks) nerve fibers maintained this capability challenging the noxa patogena that leads to their loss.