Regeneration of nerve fibers by laser irradiation of spinal nerve projections

The effect of short infrared laser irradiation on regeneration of nerve fibers in rat sciatic nerve was studied. Starting from the first day after nerve crushing, the projection of proximal portion of the nerve of the test group rats was transcutaneously stimulated by laser irradiation with the wavelength of 890 nm and total dose of 42 mJ/cm2. The test rats demonstrated higher rate of restoration of cutaneous sensitivity in comparison with control rats, which were operated but not irradiated. The local vestibular reaction occurred 2 days earlier in the test group than in the control. On day 30 after crushing there were no significant differences in the number of myelinated fibers and mass of regenerating soleus muscle in the test and control groups. ©1998 Plenum Publishing Corporation

RNA-interference in the regulation of axonal transport

Until now, in the world since literature, there has been no direct evidence indicating that RNA-interference controls local protein synthesis in the mammalian motor neuron axons. In the present review we have summarized the results on intraaxonal protein synthesis, its role in the axonal transport, and mechanisms regulating local protein synthesis in the axoplasm. The new mechanisms regulating axonal transport based on RNA-interference presented in the review let us discuss the questions about pathogenesis of the neurodegenerative diseases. The estimated role of the intraaxonal protein synthesis on axonal transport suggested applying short interfering RNA for degradation of the mutant gene RNA for blocking synthesis of the aberrant protein along the whole axon

Poly(ε-Caprolactone) nerve conduit and local delivery of vegf and fgf2 genes stimulate neuroregeneration

We studied regeneration of rat sciatic nerve while overcoming of a 5-mm diastasis with the aid of nanostructured conduit made of biocompatible and biodegradable poly(ε-caprolactone) and filled with fibrin hydrogel matrix. Implantation of the conduit into the nerve in combination with local delivery of the expression plasmid carrying genes encoding vascular endothelial growth factor (vegf) and fibroblast growth factor 2 (fgf2 ) leads to an increase in number of myelinated fibers and S-100+ cells in the peripheral nerve stump and improved recovery of the nerve function. Under conditions of direct gene therapy, an advantage of electrospun poly(ε-caprolactone) conduit with high-porosity was revealed on the basis of these criteria in comparison with biocompatible silicon conduit. © 2014 Springer Science+Business Media

Usage of plasmid vector carrying vegf and fgf2 genes after spinal cord injury in rats

Using rat model of spinal cord contusion injury at TVIII, we compared the effectiveness of immediate single transplantation of human mononuclear umbilical cord blood cells transfected with pBud-VEGF-FGF2 plasmid and immediate direct injection of the same plasmid into the lesion area. The results suggest that the delivery of therapeutic genes vegf and fgf2 in cells is more effective than direct injection of plasmid DNA with the same genes (judging from the number of myelinated fibers). Better tissue preservation and motor function recovery in experiments with direct injection of plasmid pBud-VEGF-FGF2 suggest that direct gene therapy seems to be an effective additional procedure to the method of gene delivery with transfected stem and progenitor cells. © 2013 Springer Science+Business Media New York

Resistência à seca em seringueira. II. Crescimento e partição de assimilados em clones submetidos a déficit hídrico

Plants from IAN 717, IAN 873, IAN 2903, IAN 3087, IAN 6323 and Fx 3899 rubber tree (Hevea spp.) clones grown in a greenhouse were subjected to cycles of water deficit with the objective of evaluating the effects on growth and assimilation partitioning. After 185 days and five cycles of stress, a reduction in the number of leaves, in the number of flushes, and in the length and diameter of the shoots occurred in the majority of the clones. The IAN 2903 progeny showed an increase in the number of leaves (4.7%) and in the number of flushes (10%). Shoots of the IAN 717 and IAN 3087 progenies were the least affected in their growth. The assimilation partitioning showed a modification in relation to the sinks occurring with the deficit; the prefered sinks were the root in the Fx 3899 and 873 progenies the stem in the IAN 3087 and IAN 6323 progenies and the leaf in the IAN 717 and IAN 2903 progenies. The ratio of the aerial part to the root system was greater in the IAN 2903 progeny and smaller in the Fx 3899 progeny. Under water stress no significant changes occurred in the specific leaf area production values for leaf area and in the leaf area ratio, but the net assimilation value and the accumulation and production of dry matter decreased differentially when submitted to water deficit. The clone least affected by the stress was IAN 3087. The greatest reductions on studied parameters occurred in Fx 3899. The results observed in each clone were discussed in relation to each parameter studied.Plantas de seringueira (Hevea spp) oriundas dos clones IAN 717, IAN 873, IAN 2903, IAN 3087. IAN 6323 e Fx 3899 foram cultivadas em casa-de-vegetação e submetidas a ciclos de estresse hídrico, com objetivo de avaliar comparativamente os efeitos sobre o crescimento e a partição de assimilados. Após 185 dias e cinco ciclos de estresse, o número de folhas, número de lançamentos, comprimento e diâmetro das brotações na maioria dos clones diminuíram. O IAN 2903 aumentou o número de folhas (4,7%) e o de lançamento (10%). As brotações do IAN 717 e IAN 3087 foram as menos afetadas no seu crescimento. A partição de assimilados mostrou uma modificação na preferência dos drenos com o déficit, sendo que alocação preferencial para a raiz foi do Fx 3899 e IAN 873, para o caule do IAN 3087 e IAN 6323 e para a folha do IAN 717 e IAN 2903. A relação parte aérea/sistema radicular foi maior no IAN 2903 e menor no Fx 3899. O déficit não provocou mudanças significativas na área foliar específica e na razão de peso foliar. Entretanto, a área foliar total, taxa de produção de área foliar, razão de área foliar, taxa assimilatória líquida, acúmulo e produção de matéria seca decresceram diferencialmente quando submetidos à seca. O clone menos afetado pelo estresse foi o IAN 3087. As maiores reduções nos parâmetros estudados ocorreram no Fx 3899. São discutidos os resultados de cada clone com relação a cada parâmetro estudado

Effects of transplantation of human cord blood mononuclear cells expressing the recombinant VEGF and FGF2 genes into spinal cord traumatic injury sites in rats

A model of dosed TVIII spinal cord contusion trauma in rats was used to study the effects of immediate single-dose transplantation of human cord blood mononuclear cells transformed with the recombinant genes for neurotrophic factors - vascular endothelia growth factor (VEGF) and fibroblast growth factor 2 (FGF2) - into the injury zone. A further group of animals, in the same conditions, received the same cells transfected with plasmid pEGFP-N2. EGFP-labeled cells were detected in the white matter for 21 days after transplantation at distances of at least 10 mm in the rostral and caudal directions from the administration point. By 30 days after transplantation with cells transfected with plasmid pBud-VEGF-FGF2, the area of intact gray matter 3 mm from the trauma epicenter increased by more than 60%. By this time, the outer areas of the white matter in animals of this group, 1.5 cm from the trauma epicenter, showed an average 30% increase in the number of perivascular cells expressing platelet-derived growth factor β receptors (PDGFβR). Addition of therapeutic genes VEGF an FGF2 to the trauma injury zone and their expression in carrier cells stimulated vascularization and post-traumatic regeneration of the spinal cord. © 2013 Springer Science+Business Media New York

Post-Traumatic Changes in the Spinal Cord in Rats after Transplantation of Mononuclear Cells from Human Umbilical Blood Modified with the vegf and fgf2 Genes

Experiments were carried out using 25 white laboratory rats. A model of dosed contusional trauma to the spinal cord at the T VIII level in rats was used to measure the areas of pathological cavities and the numbers of myelinated fibers in the outer zones of the white matter were counted after single rapid doses of human umbilical blood mononuclear cells transfected with a plasmid carrying the vegf and fgf2 genes into the injured area. Animals of the control group received the same cells in analogous conditions, but transfected with plasmid pEGFP-N2, carrying the gene for enhanced green fluorescent protein (egfp). By postadministration day 30, the total area of pathological cavities in the outer zones of the white matter on transverse sections of the spinal cord 3 mm from the trauma epicenter in the caudal direction was more than two times smaller in animals of the experimental group than in controls. The numbers of myelinated fibers in the same white matter zones at the same distance from the trauma epicenter in the caudal and rostral directions were an average of 20% greater than in controls, while at a distance of 5 mm in the rostral direction the number was 40-70% greater. Administration of the therapeutic genes vegf and fgf2 into the injured area decreased cavitation, restricted the processes of secondary degeneration and maintained the number of myelinated fibers in the damaged spinal cord. © 2012 Springer Science+Business Media New York

Adenoviral vector carrying glial cell-derived neurotrophic factor for direct gene therapy in comparison with human umbilical cord blood cell-mediated therapy of spinal cord injury in rat

© 2015 International Spinal Cord Society Study design:Experimental study.Objective:To evaluate the treatment of spinal cord injury with glial cell-derived neurotrophic factor (GDNF) delivered using an adenoviral vector (AdV-GDNF group) in comparison with treatment performed using human umbilical cord blood mononuclear cells (UCB-MCs)-transduced with an adenoviral vector carrying the GDNF gene (UCB-MCs+AdV-GDNF group) in rat.Setting:Kazan, Russian Federation.Methods:We examined the efficacy of AdV-GDNF and UCB-MCs+AdV-GDNF therapy by conducting behavioral tests on the animals and morphometric studies on the spinal cord, performing immunofluorescence analyses on glial cells, investigating the survival and migration potential of UCB-MCs, and evaluating the expression of the recombinant GDNF gene.Results:At the 30th postoperative day, equal positive locomotor recovery was observed after both direct and cell-based GDNF therapy. However, after UCB-MCs-mediated GDNF therapy, the area of preserved tissue and the number of spared myelinated fibers were higher than those measured after direct GDNF gene therapy. Moreover, we observed distinct changes in the populations of glial cells; expression patterns of the specific markers for astrocytes (GFAP, S100B and AQP4), oligodendrocytes (PDGFαR and Cx47) and Schwann cells (P0) differed in various areas of the spinal cord of rats treated with AdV-GDNF and UCB-MCs+AdV-GDNF.Conclusion:The differences detected in the AdV-GDNF and UCB-MCs+AdV-GDNF groups could be partially explained by the action of UCB-MCs. We discuss the insufficiency and the advantages of these two methods of GDNF gene delivery into the spinal cord after traumatic injury.Spinal Cord advance online publication, 29 September 2015; doi:10.1038/sc.2015.161

Reaction of oligoglia to spinal cord injury in rats and transplantation of human olfactory ensheathing cells

In experiments on rats with lateral TVIIIhemisection of the spinal cord and transplantation of ensheating olfactory cells, we studied structural changes at the lesion site and adjacent rostral and dorsal regions of the spinal cord. The state of oligodendrocytes and myelin fibers and motor function in experimental animal were analyzed. Open field testing (BBB test) showed that motor functions steadily increased (by 13% on average) within the interval from day 21 to day 53 after transplantation. Histological examination showed that groups of transplanted cells carrying human nuclear marker (HNu + cells) were still present at the lesion site 30 days after surgery. Some of these cells migrated in the rostral and caudal directions from the injection site to a distance up to 6 mm. At the initial period after hemisection, the number of oligodendrocytes (O4+-cells) in the immediate vicinity to the lesion site decreased 2-fold, but no signifi cant changes in the number of neurons were found in the rostral and dorsal fragments of the spinal cord compared to the corresponding parameter in controls. Sixty days after transplantation, the cross-section area in the rostral part of the spinal cord at a distance of 3 mm from damage site increased by 15.3% compared to the control. The number of O4+- cells at the lesion site and in adjacent rostral and caudal parts of the spinal cord by 22.8% surpassed that in the control group. The number of remyelinated axons also increased. These findings suggest the absence of pronounced structural changes in the rostral and caudal parts of the spinal cord compared to lesion site at early stages after damage and cell transplantation. At the same time, pronounced activation of oligodendrocytes in this region suggests their involvement together with Schwann cells into remyelination of regenerating axons, which can serve as a factor of partial restoration of motor functions after spinal cord injury. © 2010 Springer Science+Business Media, Inc

Adenoviral vector carrying glial cell-derived neurotrophic factor for direct gene therapy in comparison with human umbilical cord blood cell-mediated therapy of spinal cord injury in rat

© 2016 International Spinal Cord Society.Study design:Experimental study.Objective:To evaluate the treatment of spinal cord injury with glial cell-derived neurotrophic factor (GDNF) delivered using an adenoviral vector (AdV-GDNF group) in comparison with treatment performed using human umbilical cord blood mononuclear cells (UCB-MCs)-transduced with an adenoviral vector carrying the GDNF gene (UCB-MCs+AdV-GDNF group) in rat.Setting:Kazan, Russian Federation.Methods:We examined the efficacy of AdV-GDNF and UCB-MCs+AdV-GDNF therapy by conducting behavioral tests on the animals and morphometric studies on the spinal cord, performing immunofluorescence analyses on glial cells, investigating the survival and migration potential of UCB-MCs, and evaluating the expression of the recombinant GDNF gene.Results:At the 30th postoperative day, equal positive locomotor recovery was observed after both direct and cell-based GDNF therapy. However, after UCB-MCs-mediated GDNF therapy, the area of preserved tissue and the number of spared myelinated fibers were higher than those measured after direct GDNF gene therapy. Moreover, we observed distinct changes in the populations of glial cells; expression patterns of the specific markers for astrocytes (GFAP, S100B and AQP4), oligodendrocytes (PDGFαR and Cx47) and Schwann cells (P0) differed in various areas of the spinal cord of rats treated with AdV-GDNF and UCB-MCs+AdV-GDNF.Conclusion:The differences detected in the AdV-GDNF and UCB-MCs+AdV-GDNF groups could be partially explained by the action of UCB-MCs. We discuss the insufficiency and the advantages of these two methods of GDNF gene delivery into the spinal cord after traumatic injury