The Effect Of Acrylamide Induced Peripheral Nerve Injury And Repair In Schwann Cell Function Protein

Acrylamide (ACR) is a synthetic monomer with a wide scope of industrial applications area such as wastewater managemant, paper processing and mineral processing. The population of exposure to ACR is great. The general population can also be exposed to ACR by fried food and drinking water. Long-trem, low-level occupational exposure of humans to ACR produces neurotoxicity characterized by skeletal muscle weakness and numbness of the hands and feet, the major symptom was sensory-motory peripheral neuropathy. The impair of peripheral nerve can be healed partly when the human is out of the exposure. The supporting cells which surround the neuron may be involved in the repair process.Schwann cells (SCs) is a special glial cell in peripheral nervous system. SCs are involved in maintaining peripheral nerves normal function and repairing after the nerves were damaged. It was demonstrated that SCs construct a suitable micro-environment for nerve regenerative process by proliferation, secreting nutrition factors, producing extracellular matrix and cell adhesion molecule.The purpose of this study is exploring the role of the SCs in the process of peripheral nerve reparation. In this study, some functional proteins which are related to SCs were selected, then the level of these proteins were observed in the normal SCs, contaminated SCs, normal rats, contaminated rats and recovery rats. From the changes of the protein level, some meaningful information for the mechanism of ACR neurotoxicity and the screening of biomarker could be acquired.1. Different expression of functional proteins in SCs damaged by ACR.The MAG has not been detected by western blotting in the normal and contaminated group. The NGF has not been detected in the normal SCs, but the level of NGF increased obviously in the contaminated group.2. The changes of the functional proteins in sciatic nerve of the contaminated and recovery rats.The rats which were contaminated by ACR for 3 weeks performed hindlimb weakness, ventral tremor and increased gait score, especially the high dose group. Compared with the control group, the level of MAG decreased in the medium dose group and high dose group(p<0.05). The level of p75NTR in high dose group increased(compared with the control group, p<0.05). There were no significant change in the level of NGF between the male control group and other male contaminated groups. Compared with the male control group, the level of NCAM in the male high dose group increased(p<0.05).The gait scores of the rats which healed for 4 weeks decreased to 1-2. Compared with the control group, the level of MAG in recovery group slightly increased (p>0.05). The level of p75NTR in the recovery group was higher than the control group, the female recovery group increased obviously(p<0.05). Compared with the male control group, the level of NCAM and NGF in male recovery group increased, especially the level of NGF increased obviously(P<0.05). The level of NCAM and NGF were not detected in the female rats.3. The changes of MAG in plasma of the contaminated and recovery rats.After the measuring of ELISA, the MAG of plasma in every group was low. Compared with the control group, the level of MAG in the high dose group decreased slightly(p<0.05). The level of MAG in the recovery group was higher than the control group, but there was no significant change statistically.In conclusion, after the SCs were damaged by ACR, the increasing NGF of SCs may play a important role in protecting the damaged SCs and the neurons. The up-regulation or down-regulation of the functional proteins(MAG, p75NTR, NGF, NCAM) in the sciatic nerve of the contaminated rats and recovery rats may reflect the state of the peripheral nerve which be damaged by ACR. These changes may construct the micro-environment of the damaged and repaired peripheral nerve together. The change of MAG in rat plasma may be related with the change of MAG in sciatic nerve of the high dose contaminated group and the recovery group. The state of the peripheral nerve which be damaged by ACR could be reflected by the MAG of plasma on the other hand, so this protein might become the biomarker of ACR neuropathy.