Specificity of peripheral nerve regeneration: interactions at the axon level

TY - JOUR

T1 - Specificity of peripheral nerve regeneration

T2 - interactions at the axon level

AU - Allodi, Ilary

AU - Udina, Esther

AU - Navarro, Xavier

N1 - Copyright © 2012 Elsevier Ltd. All rights reserved.

PY - 2012/7

Y1 - 2012/7

N2 - Peripheral nerves injuries result in paralysis, anesthesia and lack of autonomic control of the affected body areas. After injury, axons distal to the lesion are disconnected from the neuronal body and degenerate, leading to denervation of the peripheral organs. Wallerian degeneration creates a microenvironment distal to the injury site that supports axonal regrowth, while the neuron body changes in phenotype to promote axonal regeneration. The significance of axonal regeneration is to replace the degenerated distal nerve segment, and achieve reinnervation of target organs and restitution of their functions. However, axonal regeneration does not always allows for adequate functional recovery, so that after a peripheral nerve injury, patients do not recover normal motor control and fine sensibility. The lack of specificity of nerve regeneration, in terms of motor and sensory axons regrowth, pathfinding and target reinnervation, is one the main shortcomings for recovery. Key factors for successful axonal regeneration include the intrinsic changes that neurons suffer to switch their transmitter state to a pro-regenerative state and the environment that the axons find distal to the lesion site. The molecular mechanisms implicated in axonal regeneration and pathfinding after injury are complex, and take into account the cross-talk between axons and glial cells, neurotrophic factors, extracellular matrix molecules and their receptors. The aim of this review is to look at those interactions, trying to understand if some of these molecular factors are specific for motor and sensory neuron growth, and provide the basic knowledge for potential strategies to enhance and guide axonal regeneration and reinnervation of adequate target organs.

AB - Peripheral nerves injuries result in paralysis, anesthesia and lack of autonomic control of the affected body areas. After injury, axons distal to the lesion are disconnected from the neuronal body and degenerate, leading to denervation of the peripheral organs. Wallerian degeneration creates a microenvironment distal to the injury site that supports axonal regrowth, while the neuron body changes in phenotype to promote axonal regeneration. The significance of axonal regeneration is to replace the degenerated distal nerve segment, and achieve reinnervation of target organs and restitution of their functions. However, axonal regeneration does not always allows for adequate functional recovery, so that after a peripheral nerve injury, patients do not recover normal motor control and fine sensibility. The lack of specificity of nerve regeneration, in terms of motor and sensory axons regrowth, pathfinding and target reinnervation, is one the main shortcomings for recovery. Key factors for successful axonal regeneration include the intrinsic changes that neurons suffer to switch their transmitter state to a pro-regenerative state and the environment that the axons find distal to the lesion site. The molecular mechanisms implicated in axonal regeneration and pathfinding after injury are complex, and take into account the cross-talk between axons and glial cells, neurotrophic factors, extracellular matrix molecules and their receptors. The aim of this review is to look at those interactions, trying to understand if some of these molecular factors are specific for motor and sensory neuron growth, and provide the basic knowledge for potential strategies to enhance and guide axonal regeneration and reinnervation of adequate target organs.

KW - Animals

KW - Axons/physiology

KW - Cell Adhesion Molecules/metabolism

KW - Extracellular Matrix/metabolism

KW - Humans

KW - Motor Neurons/physiology

KW - Nerve Growth Factors/metabolism

KW - Nerve Regeneration

KW - Peripheral Nerve Injuries/physiopathology

KW - Peripheral Nerves/physiology

KW - Schwann Cells/physiology

KW - Sensory Receptor Cells/physiology

U2 - 10.1016/j.pneurobio.2012.05.005

DO - 10.1016/j.pneurobio.2012.05.005

M3 - Review

C2 - 22609046

SN - 0301-0082

VL - 98

SP - 16

EP - 37

JO - Progress in Neurobiology

JF - Progress in Neurobiology

IS - 1

ER -