RESUMEN
Background Brachial plexus root avulsion (BPRA) can cause motor neuron death, nerve degeneration andupper limb motor dysfunction. The molecular mechanisms of motor neuron death and nerve degeneration arelargely unknown and there are no effective therapies to increase the functional recovery after BRPA.Aim: To detect the early pathway changes in spinal cord tissues after brachial plexus root avulsion.Methods A mouse brachial plexus avulsion and re-implantation model was constructed, and the C5-C7segments of the spinal cords were dissected three days after the surgery. We used RNA-seq to identify theexpression changes of genes and gene networks in spinal cord tissues.Results A total of 2253 differentially expressed genes were found significantly changed with 1852 upregulatedand 401 downregulated at 3 days after BPRA. Gene ontology (GO) enrichment analysis showed thatdifferentially expressed genes were most enriched in immune system process, regulation of immune systemprocess, defense response, plasma membrane part, extracellular region part, cell surface, protein binding,receptor binding, glycosaminoglycan binding. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathwayanalysis showed that the most enriched pathways included osteoclast differentiation, NF-kappa B, cytokinecytokine receptor interaction, TNF, hematopoietic cell lineage, complement and coagulation cascades, PI3KAkt, ECM-receptor interaction, NOD-like receptor, Toll-like receptor signaling pathway.Conclusions This study systematically identified the critical genes and signaling pathways in BPRA pathology.These results expand our understanding of the complex molecular mechanisms involved in BPRA and provide afoundation for future research of spinal cord tissue injury and repair.
RESUMEN
Ventral root avulsion (VRA) is an experimental approach in which there is an abrupt separation of the motor roots from the surface of the spinal cord. As a result, most of the axotomized motoneurons degenerate by the second week after injury, and the significant loss of synapses and increased glial reaction triggers a chronic inflammatory state. Pharmacological treatment associated with root reimplantation is thought to overcome the degenerative effects of VRA. Therefore, treatment with dimethyl fumarate (DMF), a drug with neuroprotective and immunomodulatory effects, in combination with a heterologous fibrin sealant/biopolymer (FS), a biological glue, may improve the regenerative response. Methods: Adult female Lewis rats were subjected to VRA of L4-L6 roots followed by reimplantation and daily treatment with DMF for four weeks. Survival times were evaluated 1, 4 or 12 weeks after surgery. Neuronal survival assessed by Nissl staining, glial reactivity (anti-GFAP for astrocytes and anti-Iba-1 for microglia) and synapse preservation (anti-VGLUT1 for glutamatergic inputs and anti-GAD65 for GABAergic inputs) evaluated by immunofluorescence, gene expression (pro- and anti-inflammatory molecules) and motor function recovery were measured. Results: Treatment with DMF at a dose of 15 mg/kg was found to be neuroprotective and immunomodulatory because it preserved motoneurons and synapses and decreased astrogliosis and microglial reactions, as well as downregulated the expression of pro-inflammatory gene transcripts. Conclusion: The pharmacological benefit was further enhanced when associated with root reimplantation with FS, in which animals recovered at least 50% of motor function, showing the efficacy of employing multiple regenerative approaches following spinal cord root injury.(AU)
Asunto(s)
Animales , Productos Biológicos , Biopolímeros , Fibrina , Inmunomodulación , Dimetilfumarato , Neuroprotección , Expresión GénicaRESUMEN
Objective To evaluate the long-term functional recovery after contralateral 7th cervical nerve(C7) transfer with brachial plexus root avulsion and the effect on the contralateral limbs after operation. Methods A total of 83 patients with injory of brachial plexus avulsion were underwent contralateral C7 transfer from September, 2004 to December, 2014.Among them, contralateral C7 were transferred to the median nerve in 33 cases, to radial nerve in 14 cases, to musculocutaneous nerve in 22 cases, and simultaneous transfer to median and musculocutaneous nerve in 14 cases.The followed-up contents included recovery of muscular strength and sensory innervated by the recipient nerve, bilateral limbs synergistic activity and the effect on the contralateral limbs after the surgery. Results All 83 cases were successfully followed-up for 3.2-6.2 years (average, 4.5 years), and found no significant effect on function of the contralateral limbs. In the group of C7 transferred to the median nerve group, 10 cases had muscle strength recov鄄ered≥M3, and 26 cases had sensory recovered≥S3; In the group of C7 transferred to the radial nerve, 6 cases had muscle strength recovered≥M3, and 9 cases had sensory recovered ≥S3; In the group of C7 transferred to the muscu鄄locutaneous nerve, 12 cases had muscle strength recovered≥M3, and 17 cases had sensory recovered≥S3.In the group of C7 simultaneous transferred to the median and musculocutaneous nerve, 6 cases had muscle strength of wrist and digital flexion recovered≥M3, 5 cases had elbow flexion recovered≥M3, 9 and 10 cases had sensory of innervated area and lateral forearm region recovered≥S3, respectively. Conclusion Contralateral C7 transfer is an ideal procedure for the treatment of total brachial plexus root avulsion with definitive clinical outcomes.
RESUMEN
Objective@#To evaluate the long-term functional recovery after contralateral 7th cervical nerve(C7) transfer with brachial plexus root avulsion and the effect on the contralateral limbs after operation.@*Methods@#A total of 83 patients with injory of brachial plexus avulsion were underwent contralateral C7 transfer from September, 2004 to December, 2014. Among them, contralateral C7 were transferred to the median nerve in 33 cases, to radial nerve in 14 cases, to musculocutaneous nerve in 22 cases, and simultaneous transfer to median and musculocutaneous nerve in 14 cases. The followed-up contents included recovery of muscular strength and sensory innervated by the recipient nerve, bilateral limbs synergistic activity and the effect on the contralateral limbs after the surgery.@*Results@#All 83 cases were successfully followed-up for 3.2-6.2 years (average, 4.5 years), and found no significant effect on function of the contralateral limbs. In the group of C7 transferred to the median nerve group, 10 cases had muscle strength recovered≥M3, and 26 cases had sensory recovered≥S3; In the group of C7 transferred to the radial nerve, 6 cases had muscle strength recovered≥M3, and 9 cases had sensory recovered ≥S3; In the group of C7 transferred to the musculocutaneous nerve, 12 cases had muscle strength recovered≥M3, and 17 cases had sensory recovered≥S3. In the group of C7 simultaneous transferred to the median and musculocutaneous nerve, 6 cases had muscle strength of wrist and digital flexion recovered≥M3, 5 cases had elbow flexion recovered≥M3, 9 and 10 cases had sensory of innervated area and lateral forearm region recovered≥S3, respectively.@*Conclusion@#Contralateral C7 transfer is an ideal procedure for the treatment of total brachial plexus root avulsion with definitive clinical outcomes.
RESUMEN
Objective To establish a rat model of spinal root avulsion and to validate the model by brain-derived neurotrophic factor(BDNF)treatment. Methods To evaluate the motor neuron loss,5 male SD rats were used to undergo spinal root avulsion surgery. One week later, the number of motor neurons in the ventral horn of the spinal cord was as-sessed by histopathology using immunohistochemical staining with a choline acetyl transferase(ChAT)antibody. After this pilot study,40 male SD rats at 7 weeks of age were randomly divided into 4 groups:two control groups,BDNF preventive and treatment groups. Results All rats recovered well post-surgery and no obvious abnormality was observed. Compared with the contralateral side,the number of motor neurons in the ipsilateral avulsed side was significantly decreased at one week after surgery(20.06%,P<0.05). Compared with the control group,there was a significant increase in ChAT posi-tive neurons in the BDNF preventive group(17.85% vs. 93.06%,P<0.0001)or BDNF treatment group(1week after surgery)(26.94% vs. 86.87%, P<0.0001), indicating that the motor neurons were effectively protected by BDNF. Conclusions A rat model of spinal root avulsion is successfully established,which can be valuable for studies of amyotro-phic lateral sclerosis and drug discovery efforts.
RESUMEN
Objetivo: La cirugía de reparación nerviosa es la primera elección en lesiones del plexo braquial. La artrodesis de hombro estabiliza y otorga cierta abducción por desplazamiento de la escápula. El objetivo del presente trabajo es: comparar la artrodesis de hombro versus la transferencia del nervio espinal accesorio al supraescapular. Materiales y métodos: se analizaron en forma retrospectiva 20 pacientes con parálisis completa del miembro superior y avulsión radicular de al menos 4 raíces. Diez fueron artrodesados, y en los otros 10 se realizó una única transferencia nerviosa para el hombro, antes citada. El seguimiento mínimo fue de 2 años. Se determinó la abducción en grados y se describió una escala para estudiar los resultados de ambas técnicas. Los resultados fueron comparados estadísticamente. Resultados: en los pacientes artrodesados el promedio, según la escala, fue 4,5 puntos, mientras que en los transferidos fue 4,8. La media de abducción en grados fue de 37 en artrodesados y 43,5 en transferidos. No se encontraron diferencias estadísticamente significativas entre ambos grupos. Conclusiones: los resultados de ambas técnicas son semejantes. La artrodesis escápulo-humeral es una posibilidad terapéutica aceptable del hombro paralizado en los pacientes con lesiones muy graves del plexo braquial y escasez de donantes nerviosos.
Objective: Primary nerve reconstruction surgery is the gold standard in brachial plexus injuries. Shoulder arthrodesis stabilizes and abducts the shoulder by the movement of the scapula. The goal of the present study is to compare shoulder arthrodesis versus spinal nerve transfer to supraescapular nerve. Materials y methods: 20 patients with complete brachial plexus palsy (flail arm) and at least 4 roots avulsions were analyzed retrospectively. Ten were submitted to shoulder arthrodesis, while in the other 10, only one nerve transfer was performed to reinervate the shoulder. Minimum follow-up was 2 years. The results were determined in degrees of abduction, also measured in a scale, and compared statistically. Results: the mean result in the patients with shoulder arthrodesis was 4.5, and 4.8 in the nerve transferred. Mean final abduction was 37 degrees in arthrodesis and 43.5 in nerve transfer. No statistical significant difference was found between groupsConclusions: the results of both techniques are similar. Shoulder arthrodesis is a viable option in severely injured brachial plexus patients where donor nerve are scarce.
Asunto(s)
Humanos , Artrodesis , Plexo Braquial , HombroRESUMEN
Objective To discuss the characteristic of brachial plexus root avulsion injury of high resolution MR imaging and the value in diagnosing of brachial plexus root avulsion injury early.Methods Fourty-five cases of brachial plexus root avulsion injury patients had being used for investigation to find the characteristic and diagnostic value of MR image of brachial plexus root avulsion injury,which all have pre-operative MR imaging and were diagnosed brachial plexus root avulsion injury by intra-operative exploration and electrophysiology form February 2006 to February 2011.Results Post-traumatic spinalmeningolceles were seen in 42 cases,the frequency was 93.3％; Displacement of spinal cord was seen in 25 cases,the frequency was 55.6％; Absence of anterior and posterior root of spinal nerve was seen in 8 eases,the frequency was 17.8％;Black line sign was seen in 18 cases,the frequency was 40.0％.The sensitivity,specificity,and accuracy of MRI in diagnosing brachial plexus root injury were 95.7％,77.8％ and 94.6％ respectively.Conclusion Posttraumatic spinalmeningolceles are most often seen in MR of brachial plexus root avulsion injury,this sign can play an important role in diagnosing and treatment of brachial plexus root avulsion injury.
RESUMEN
Objective To explore the clinical design and therapeutic effect of total root avulsion of brachial plexus by contralateral C_7 nerve transfer for directly repairing C_8T_1 via prespinal route combined with functioning gracilis transplantation. Methods Twelve cases of total roots avulsion of brachial plexus were operated at 1 month to 3 months after injury.The contralateral C_7 nerve was successfully transferred to directly repair avulsed C_8T_1 roots or lower trunk via prespinal route.At 2nd operation stage after 4 to 8 months,the functioning gracills transplantation was preformed to reconstruct the elbow flexion and fingers extension. Results Follow-ups were carried out in all 12 cases who had been discharged for 9 to 36 months after the first operation.The positive Tinel signs of ulnar or median nerves were located in the proximal arm at 3 months after 1st operation,in the elbow or proximal forarm at 6 months,and in the wrist or distal forarm at 9 months.At 12 months the positive Tinel signs were found in the plam or fingers in 9 cases.The contraction of sternocostal part of pectoralis major was found at 9 mooths in 7 cases.There were the restoration of the taction-pain sensation in the palm, finger, and medial side of forearm and the contraction of flexor carpi ulnaris and flexor digitorum(M_3)in 5 cases at 15 to 18 months after 1st operation.In 7 patients the flexion of elbow and extension of fingers and thumb restored at 9 to 12 months after the 2nd operation.Their elbow flexion was 90°-120°and M_3(Highet's method),and their finger and thumb extension M_3. Conclusion There is the possibility of the operative design and clinical application of total root avulsion of brachial plexus by contralateral C_7 nerve transfer for directly repairing C_8T_1 via prespinal route combined with functioning gracilis transplantation.There are not only the restoration of sensation and flexion of wrist and fingers,but also the restoration of elbow flexion and fingers extension.
RESUMEN
The morphological changes in the anterior horn of the L4 and L5 spinal segments were observed following anterior root avulsion in the adult male Sprague-Dawley rat (300~350 gm) at 5 days, 1 week, 2 weeks and 3 weeks postlesion. The animals were perfused with 4% paraformaldehyde, 0.15% picric acid in 0.1 M phosphate buffer solution and cryostat sections were prepared. Immunohistochemistry was used to identify changes of the phenotype in the anterior horn cells. Primary antibodies, goat anti-choline acetyltransferase (ChaT, 1 : 500, Chemicon), mouse antirat ED-1 (1 : 200, Serotec), rabbit anti-glial fibrillary acidic protein (GFAP, 1 : 200, DAKO) and rabbit anti-vascular endothelial growth factor (VEGF, 1 : 500, Santa Cruz Biotechnology) were used. Avidin-Biotin complex method was performed for immunohistochemical reaction and color reaction was developed with DAB-H2O2. Following results were observed in the anterior horn of lumbar spinal cord; 1. The number of ChaT-immunoreactive (ir) cells were reduced 20% level of control animals at 3 weeks after avulsion. 2. ED-1-ir microglia were significantly increased at 1 week and processes of ED-1-ir microglia surrounded around the axotomized neuronal cell bodies. 3. Gliosis defined by extensive GFAP immunoreactivity was observed both ipsilateral and contralateral side of lesion but the VEGF-ir cells were significantly increased in the ipsilateral side of lesion. Therefore, this study suggested that the majority of axotomized motor neurons were degenerated and the cellular proliferation and phenotype changes including glial cell activation were observed in the lumbar spinal cord after anterior root avulsion of adult rats.
Asunto(s)
Adulto , Animales , Humanos , Masculino , Ratones , Ratas , Células del Asta Anterior , Anticuerpos , Proliferación Celular , Colina O-Acetiltransferasa , Factores de Crecimiento Endotelial , Gliosis , Cabras , Cuernos , Inmunohistoquímica , Microglía , Neuronas Motoras , Neuroglía , Neuronas , Fenotipo , Ratas Sprague-Dawley , Médula Espinal , Factor A de Crecimiento Endotelial VascularRESUMEN
Important breakthroughs in the understanding regeneration failure in an injured CNS have been made by studies of primary afferent neurons. Dorsal rhizotomy has provided an experimental model of brachial plexus (BP) avulsion. This is an injury in which the central branches of primary afferents are disrupted at their point of entry into the spinal cord, bringing motor and sensory dysfunction to the upper limbs. In the present work, the central axonal organization of primary afferents was examined in control (without lesion) adult Wistar rats and in rats subjected to a C3-T3 rhizotomy. Specific sensory axon subtypes were recognized by application of antibodies to the calcitonin gene-related peptide (CGRP), the P2X3 purinoreceptor, the low-affinity p75-neurotrophin receptor and the retrograde tracer cholera toxin subunit beta (TCbeta ). Other subtypes weres labeled with the lectin Griffonia simplicifolia IB4. Using immunohistochemistry and high resolution light microscopy, brachial plexus rhizotomy in adult rats has proven a reliable model for several neural deficits in humans. This lesion produced different degrees of terminal degeneration in the several types of primary afferents which define sub-populations of sensitive neurons. Between the C6 and C8 levels of the spinal cord,,deafferentation was partial for peptidergic GCRP-positive fibers, in contrast with elimination of non peptidergic and myelinated fibers. Dorsal rhizotomy has provided an adequate experimental model to study sensory alterations such as acute pain and allodynia as well as factors that affect regeneration into the CNS., Therefore, the differential deafferentation response must be considered inr the evaluation of therapies for nociception (pain) and regeneration for brachial plexus avulsion. The anatomical diffierences among the primary afferent subtypes also affect their roles in normal and damaged conditions.
El uso de las neuronas sensoriales primarias ha aportado avances en el entendimiento de las razones por las cuales falla la regeneración cuando el sistema nervioso central (SNC) es dañado. La rizotomía dorsal se puede usar como un modelo experimental de las lesiones por avulsión del plexo braquial, una lesión en la cual son desprendidas, en su punto de entrada en la médula espinal, las ramas centrales de los aferentes primarios causando una disfunción motora y sensorial grave e irreversible del miembro superior. En el presente trabajo, se examinó la organización central de los aferentes primarios en ratas Wistar adultas. Éstas fueron divididas en controles normales no lesionados y en animales rizotomizados entre los niveles cervical 3 y torácico 3 (C3-T3). Se estudió la deaferentación de los subtipos de axones sensoriales utilizando anticuerpos específicos contra el péptido relacionado con el gen de la calcitonina (CGRP), el receptor purinérgico (P2X3), el receptor de baja afinidad p75 para el factor de crecimiento nervioso (NGF) y contra la subunidad ®de la toxina de cólera (TCbeta ). Otro subtipo fue marcado con la lectina Griffonia simplicifolia IB4. La inmunohistoquímica y la microscopía óptica de alta resolución demostraron que el modelo animal de rizotomía completa del plexo braquial reproduce diversos déficit observados en las lesiones humanas. Esta lesión produce diferentes grados de degeneración terminal entre los diversos tipos de aferentes primarios que definen subpoblaciones de neuronas sensoriales. En los niveles de la médula espinal estudiados (entre C6 y C8), la deaferentación fue parcial para las fibras peptidérgicas GCRPpositivas, en contraste con la eliminación de las fibras no peptidérgicas y las mielinizadas. La rizotomía dorsal es un modelo experimental apropiado para estudiar las alteraciones sensoriales como el dolor agudo y la alodinia, así como los factores que podrían afectar la regeneración en el SNC. Por tanto, la respuesta de deaferentacion diferencial debe ser tenida en cuenta para la evaluación de terapias antinociceptivas y regenerativas tras la avulsión del plexo braquial. Se discute la anatomía de los subtipos de aferentes primarios y su papel en condiciones normales y después de la lesión.
Asunto(s)
Animales , Masculino , Ratas , Plexo Braquial/lesiones , Modelos Animales de Enfermedad , Neuronas Aferentes/patología , Axones , Neuronas Aferentes/citología , Ratas Wistar , RizotomíaRESUMEN
This study investigated the expression of osteopontin (OPN) in rat lumbar spinal cords after lumbar nerve root avulsion, using in situ hybridization histochemistry, immunocytochemistry and western blot analysis. Cells expressing OPN were motoneurons and interneurons in the ventral horn, but no signals were observed in neurons in the dorsal horn of the normal lumbar spinal cord. From day 1 after avulsion injury, OPN mRNA-labeled neurons increased in the ventral horn and the intermediate zone. By day 3, relatively strong OPN mRNA signals were found throughout the gray matter of the injured side of the spinal cord with OPN mRNA-labeled cells scattered in the superficial dorsal horn. By day 7, the labeling patterns for OPN mRNA were similar to those on day 3, but the numbers of OPN mRNA-labeled cells in the ventral horn and the intermediate zone peaked. At this point, these labeled cells were also more densely packed and the intensity of signals was stronger. Interestingly, these labeled cells were neurons, but not glial cells such as astrocytes or microglia. This OPN mRNA-labeled cell profile in the dorsal horn had nearly disappeared by day 14 after avulsion injury, and the labeling pattern became similar to that on day 1. By day 28, after avulsion injury, the numbers of OPN mRNA-labeled cells decreased further below control values. These results suggest that increased expression of OPN in the rat lumbar spinal cord after avulsion injury might play an important role in the pathogenesis of damaged neurons.
Asunto(s)
Animales , Ratas , Astrocitos , Western Blotting , Cuernos , Inmunohistoquímica , Hibridación in Situ , Interneuronas , Microglía , Neuroglía , Neuronas , Osteopontina , Radiculopatía , ARN Mensajero , Médula EspinalRESUMEN
Objective To compare the effect of natural antioxidants TA9001 and EGb761 on c-jun, NOS expression and survival of spinal motoneurons following brachial roots avulsion. Methods One hundred and eighty adult Sprague-Dawley female rats were randomly divided into TA9001, ECb761 and control groups. The right C 5～T 1 nerve roots were avulsed and then the introperitoneal injection of 1ml of 0.5% TA9001, 0.5% EGb761 or normal saline was given immediately and once daily to the rats, respectively. The rats were killed after survival for 4 h, 12 h 1 d,3 d,5 d,and 1 week, 2 weeks, 4 weeks and 6 weeks. The cryostat sections of C 7 segment were prepared and carried with c-jun immunocytochemistry, NADPH-d histochemistry and neutral red counter stain. Results The c-jun and nNOS gene expression was only appeared in injured motoneurons. c-jun was first appeared at 4 h, reached its maximum at 1 d, and grandually decreased till 2 weeks. NOS was first checked at 5 d, mostly at 2 weeks and decreased until 6 weeks. Avulsed motoneuron death started at 2 weeks, reached its peak at 4～6 weeks. Both TA9001 and EGb761 can cause c-jun up-regulation, nNOS down-regulation and more motoneuron survival as compared to control. Furthermore, EGb761 had more power to enhance c-jun expression than TA9901 at each time point. Conclusion It seems that nNOS is more important in motoneuron death mechanism than c-jun. Treatment of either TA9901 or EGb761 can protect the injured motoneurons following root avulsion.
RESUMEN
We have described the intercostal nerve transfer to musculocutaneous nerve for three patients with root-avulsion type brachial plexus complete injuries. Surgical technique and some considerations about the operation have been discussed.