Pharmacological immunomodulation enhances peripheral nerve regeneration

Abstract

To assess the effect of N-Acetylmuramyl-L-Alanyl-D-Isoglutamine MDP topically administrated on the regenerating peripheral neurons, twelve male C57BL/6J adult mice were equally distributed into three groups. Four mice underwent unilateral sciatic nerve transection and polyethylene tubulization, with a 4mm gap between the proximal and distal nerve stumps and were implanted with collagen + PBS (COL). Other four animals underwent the same surgical procedure but received collagen + MDP (COL/MDP) inside the prosthesis. Four animals were not operated and served as control group (NOR). After 4 weeks, the regenerated nerve cables were processed for total myelinated axon counting and myelinated fiber diameter measurement. The L5 dorsal root ganglion (DRG) was also removed and sectioned for sensory neurons counting and measurement. The results revealed significant difference (p<0.05) in axonal counting among the groups NOR (4,355±32), COL (1,869±289) and COL/MDP (2,430±223). There was a significant reduction in the axonal diameter in the operated groups (COL=3.38µm±1.16 and COL/MDP=3.54µm±1.16) compared to NOR (6.19µm±2.45). No difference was found in the number of DRG neurons between the experimental groups (COL=564±51; COL/MDP=514±56), which presented fewer sensory neurons compared to NOR (1,097±142). Data obtained indicate that locally applied MDP stimulates peripheral nerve regeneration in mice.

Morfofisiologia da inervação do diafragma de ovinos

“…Os resultados sugerem que os nervos intercostais, e especialmente do 7º ao 9º são importantes vias eferentes para algumas dessas ações ou reflexos. Por fim, os nervos intercostais devem ser lembrados em relação a sua ação entre diafragma e nervo frênico descritos em catetos por Moura et al (2007) e suas funções bási-cas na manutenção da homeostase animal e mecanismos respiratórios, além de ressaltarmos a importância de pesquisas básicas morfofisiológicas para embasar estudos visando à regeneração nervosa (Inoe et al 2007). …”

Enhanced Femoral Nerve Regeneration After Tubulization with a Tyrosine-Derived Polycarbonate Terpolymer: Effects of Protein Adsorption and Independence of Conduit Porosity

“…13 Nondegradable polyethylene (PE) has shown similar capabilities, but thus far only in animal models. [14][15][16] Whereas these conduits have provided an important benchmark for nerve regeneration, their inability to degrade can result in chronic host tissue response and/or nerve compression months after implantation, deterring regeneration. [17][18][19] To avoid these issues, biodegradable materials have been developed and utilized for the fabrication of nerve conduits.…”

Effect of neurotrophic factor, MDP, on rats’ nerve regeneration

“…When injected into the crushed sciatic nerve, MDP activates macrophages and promotes recovery of walking locomotion in rats (3). Some results indicate that locally applied MDP stimulates peripheral nerve regeneration in rats (4). Based on the feasibility of using fibrin glue mixed with the neurotrophic factor, we decided to study the immunomodulatory effect of MDP on the process of peripheral nerve regeneration in a rat experimental model.…”