1
|
Kempe PRG, Chiarotto GB, Barraviera B, Ferreira RS, de Oliveira ALR. Neuroprotection and immunomodulation by dimethyl fumarate and a heterologous fibrin biopolymer after ventral root avulsion and reimplantation. J Venom Anim Toxins Incl Trop Dis 2020; 26:e20190093. [PMID: 32518556 PMCID: PMC7250131 DOI: 10.1590/1678-9199-jvatitd-2019-0093] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Background: 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.
Collapse
Affiliation(s)
- Paula R G Kempe
- Laboratory of Nerve Regeneration, University of Campinas (UNICAMP), Campinas, SP, Brazil
| | | | - Benedito Barraviera
- Center for the Study of Venoms and Venomous Animals (CEVAP), São Paulo State University (UNESP), Botucatu, SP, Brazil
| | - Rui Seabra Ferreira
- Center for the Study of Venoms and Venomous Animals (CEVAP), São Paulo State University (UNESP), Botucatu, SP, Brazil
| | | |
Collapse
|
2
|
Chang HH, Yeh JC, Ichiyama RM, Rodriguez LV, Havton LA. Mapping and neuromodulation of lower urinary tract function using spinal cord stimulation in female rats. Exp Neurol 2018. [PMID: 29530711 DOI: 10.1016/j.expneurol.2018.03.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Spinal cord epidural stimulation (SCS) represents a form of neuromodulation for the management of spasticity and pain. This technology has recently emerged as a new approach for potentially augmenting locomotion and voiding function in humans and rodents after spinal cord injury. However, the effect of SCS on micturition has not been studied extensively. Here, SCS was first applied as a direct stimulus onto individual segmental levels of the lumbar spinal cord in rats to map evoked external urethral sphincter (EUS) electromyography activity and SCS-induced voiding contractions. SCS of L2-3 inhibited EUS tonic activity, and SCS on L3 (L3/SCS) inhibited EUS tonic activity and elicited EUS bursting. In contrast, SCS of L1 and L4-6 evoked EUS tonic contractions, which resembled the urethral guarding reflex during bladder storage. Next, the effects of a bilateral pelvic nerve crush (PNC) injury on urodynamic function were examined at 14 days post-operatively. The PNC injury resulted in decreased voiding efficiency and maximum intravesical pressure, whereas the post-voiding residual volume was increased, suggestive of an underactive bladder. Finally, L3/SCS was performed to induce a voiding contraction and enable voiding in rats with a PNC injury. Voiding efficiency was significantly increased, and the residual volume was decreased by L3/SCS in rats after the PNC injury. We conclude that L3/SCS may be used to induce micturition reflexes in a partially filled bladder, reduce urethral resistance, and augment bladder emptying after PNC injury.
Collapse
Affiliation(s)
- Huiyi H Chang
- Urology, University of California Irvine, CA, USA; Reeve-Irvine Research Center, University of California Irvine, CA, USA.
| | - Jih-Chao Yeh
- Urology, University of Southern California, CA, USA
| | | | | | - Leif A Havton
- Neurology and Neurobiology, University of California Los Angeles, CA, USA
| |
Collapse
|
3
|
Chang HH, Havton LA. A ventral root avulsion injury model for neurogenic underactive bladder studies. Exp Neurol 2016; 285:190-196. [PMID: 27222131 DOI: 10.1016/j.expneurol.2016.05.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 05/18/2016] [Accepted: 05/20/2016] [Indexed: 10/21/2022]
Abstract
Detrusor underactivity (DU) is defined as a contraction of reduced strength and/or duration during bladder emptying and results in incomplete and prolonged bladder emptying. The clinical diagnosis of DU is challenging when present alone or in association with other bladder conditions such as detrusor overactivity, urinary retention, detrusor hyperactivity with impaired contractility, aging, and neurological injuries. Several etiologies may be responsible for DU or the development of an underactive bladder (UAB), but the pathobiology of DU or UAB is not well understood. Therefore, new clinically relevant and interpretable models for studies of UAB are much needed in order to make progress towards new treatments and preventative strategies. Here, we review a neuropathic cause of DU in the form of traumatic injuries to the cauda equina (CE) and conus medullaris (CM) portions of the spinal cord. Lumbosacral ventral root avulsion (VRA) injury models in rats mimic the clinical phenotype of CM/CE injuries. Bilateral VRA injuries result in bladder areflexia, whereas a unilateral lesion results in partial impairment of lower urinary tract and visceromotor reflexes. Surgical re-implantation of avulsed ventral roots into the spinal cord and pharmacological strategies can augment micturition reflexes. The translational research need for the development of a large animal model for UAB studies is also presented, and early studies of lumbosacral VRA injuries in rhesus macaques are discussed.
Collapse
Affiliation(s)
- Huiyi H Chang
- Institute of Urology, University of Southern California, Los Angeles, CA, United States.
| | - Leif A Havton
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States
| |
Collapse
|
4
|
Neuromodulation of the neural circuits controlling the lower urinary tract. Exp Neurol 2016; 285:182-189. [PMID: 27381425 DOI: 10.1016/j.expneurol.2016.06.034] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Revised: 06/30/2016] [Accepted: 06/30/2016] [Indexed: 01/01/2023]
Abstract
The inability to control timely bladder emptying is one of the most serious challenges among the many functional deficits that occur after a spinal cord injury. We previously demonstrated that electrodes placed epidurally on the dorsum of the spinal cord can be used in animals and humans to recover postural and locomotor function after complete paralysis and can be used to enable voiding in spinal rats. In the present study, we examined the neuromodulation of lower urinary tract function associated with acute epidural spinal cord stimulation, locomotion, and peripheral nerve stimulation in adult rats. Herein we demonstrate that electrically evoked potentials in the hindlimb muscles and external urethral sphincter are modulated uniquely when the rat is stepping bipedally and not voiding, immediately pre-voiding, or when voiding. We also show that spinal cord stimulation can effectively neuromodulate the lower urinary tract via frequency-dependent stimulation patterns and that neural peripheral nerve stimulation can activate the external urethral sphincter both directly and via relays in the spinal cord. The data demonstrate that the sensorimotor networks controlling bladder and locomotion are highly integrated neurophysiologically and behaviorally and demonstrate how these two functions are modulated by sensory input from the tibial and pudental nerves. A more detailed understanding of the high level of interaction between these networks could lead to the integration of multiple neurophysiological strategies to improve bladder function. These data suggest that the development of strategies to improve bladder function should simultaneously engage these highly integrated networks in an activity-dependent manner.
Collapse
|
5
|
Barbizan R, Castro MV, Ferreira RS, Barraviera B, Oliveira ALR. Long-term spinal ventral root reimplantation, but not bone marrow mononuclear cell treatment, positively influences ultrastructural synapse recovery and motor axonal regrowth. Int J Mol Sci 2014; 15:19535-51. [PMID: 25353176 PMCID: PMC4264127 DOI: 10.3390/ijms151119535] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 09/27/2014] [Accepted: 10/11/2014] [Indexed: 12/13/2022] Open
Abstract
We recently proposed a new surgical approach to treat ventral root avulsion, resulting in motoneuron protection. The present work combined such a surgical approach with bone marrow mononuclear cells (MC) therapy. Therefore, MC were added to the site of reimplantation. Female Lewis rats (seven weeks old) were subjected to unilateral ventral root avulsion (VRA) at L4, L5 and L6 levels and divided into the following groups (n = 5 for each group): Avulsion, sealant reimplanted roots and sealant reimplanted roots plus MC. After four weeks and 12 weeks post-surgery, the lumbar intumescences were processed by transmission electron microscopy, to analyze synaptic inputs to the repaired α motoneurons. Also, the ipsi and contralateral sciatic nerves were processed for axon counting and morphometry. The ultrastructural results indicated a significant preservation of inhibitory pre-synaptic boutons in the groups repaired with sealant alone and associated with MC therapy. Moreover, the average number of axons was higher in treated groups when compared to avulsion only. Complementary to the fiber counting, the morphometric analysis of axonal diameter and “g” ratio demonstrated that root reimplantation improved the motor component recovery. In conclusion, the data herein demonstrate that root reimplantation at the lesion site may be considered a therapeutic approach, following proximal lesions in the interface of central nervous system (CNS) and peripheral nervous system (PNS), and that MC therapy does not further improve the regenerative recovery, up to 12 weeks post lesion.
Collapse
Affiliation(s)
- Roberta Barbizan
- Department of Structural and Functional Biology, University of Campinas (UNICAMP), PO Box 6109, Campinas 13083-970, São Paulo, Brazil.
| | - Mateus V Castro
- Department of Structural and Functional Biology, University of Campinas (UNICAMP), PO Box 6109, Campinas 13083-970, São Paulo, Brazil.
| | - Rui Seabra Ferreira
- Center for the Study of Venoms and Venomous Animals (CEVAP), São Paulo State University (UNESP), Botucatu 18610-307, São Paulo, Brazil.
| | - Benedito Barraviera
- Center for the Study of Venoms and Venomous Animals (CEVAP), São Paulo State University (UNESP), Botucatu 18610-307, São Paulo, Brazil.
| | - Alexandre L R Oliveira
- Department of Structural and Functional Biology, University of Campinas (UNICAMP), PO Box 6109, Campinas 13083-970, São Paulo, Brazil.
| |
Collapse
|
6
|
Barbizan R, Castro MV, Barraviera B, Ferreira RS, Oliveira ALR. Influence of delivery method on neuroprotection by bone marrow mononuclear cell therapy following ventral root reimplantation with fibrin sealant. PLoS One 2014; 9:e105712. [PMID: 25157845 PMCID: PMC4144952 DOI: 10.1371/journal.pone.0105712] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2014] [Accepted: 07/23/2014] [Indexed: 12/11/2022] Open
Abstract
The present work compared the local injection of mononuclear cells to the spinal cord lateral funiculus with the alternative approach of local delivery with fibrin sealant after ventral root avulsion (VRA) and reimplantation. For that, female adult Lewis rats were divided into the following groups: avulsion only, reimplantation with fibrin sealant; root repair with fibrin sealant associated with mononuclear cells; and repair with fibrin sealant and injected mononuclear cells. Cell therapy resulted in greater survival of spinal motoneurons up to four weeks post-surgery, especially when mononuclear cells were added to the fibrin glue. Injection of mononuclear cells to the lateral funiculus yield similar results to the reimplantation alone. Additionally, mononuclear cells added to the fibrin glue increased neurotrophic factor gene transcript levels in the spinal cord ventral horn. Regarding the motor recovery, evaluated by the functional peroneal index, as well as the paw print pressure, cell treated rats performed equally well as compared to reimplanted only animals, and significantly better than the avulsion only subjects. The results herein demonstrate that mononuclear cells therapy is neuroprotective by increasing levels of brain derived neurotrophic factor (BDNF) and glial derived neurotrophic factor (GDNF). Moreover, the use of fibrin sealant mononuclear cells delivery approach gave the best and more long lasting results.
Collapse
Affiliation(s)
- Roberta Barbizan
- Laboratory of Nerve Regeneration, Department of Structural and Functional Biology, University of Campinas - UNICAMP, Campinas, São Paulo, Brazil
| | - Mateus V. Castro
- Laboratory of Nerve Regeneration, Department of Structural and Functional Biology, University of Campinas - UNICAMP, Campinas, São Paulo, Brazil
| | - Benedito Barraviera
- Center for the Study of Venoms and Venomous Animals (CEVAP), São Paulo State University (UNESP – Univ Estadual Paulista), Botucatu, São Paulo, Brazil
| | - Rui S. Ferreira
- Center for the Study of Venoms and Venomous Animals (CEVAP), São Paulo State University (UNESP – Univ Estadual Paulista), Botucatu, São Paulo, Brazil
| | - Alexandre L. R. Oliveira
- Laboratory of Nerve Regeneration, Department of Structural and Functional Biology, University of Campinas - UNICAMP, Campinas, São Paulo, Brazil
| |
Collapse
|
7
|
Chew DJ, Murrell K, Carlstedt T, Shortland PJ. Segmental spinal root avulsion in the adult rat: a model to study avulsion injury pain. J Neurotrauma 2013; 30:160-72. [PMID: 22934818 DOI: 10.1089/neu.2012.2481] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Road traffic accidents are the most common cause of avulsion injury, in which spinal roots are torn from the spinal cord. Patients suffer from a loss of sensorimotor function, intractable spontaneous pain, and border-zone hypersensitivity. The neuropathic pains are particularly difficult to treat because the lack of a well-established animal model of avulsion injury prevents identifying the underlying mechanisms and hinders the development of efficacious drugs. This article describes a hindlimb model of avulsion injury in adult rats where the L5 dorsal and ventral spinal root are unilaterally avulsed (spinal root avulsion [SRA]), leaving the adjacent L4 spinal root intact. SRA produced a significant ipsilateral hypersensitivity to mechanical and thermal stimulation by 5 days compared with sham-operated or naïve rats. This hypersensitivity is maintained for up to 60 days. No autotomy was observed and locomotor deficits were minimal. The hypersensitivity to peripheral stimuli could be temporarily ameliorated by administration of amitriptyline and carbamazepine, drugs that are currently prescribed to avulsion patients. Histological assessment of the L4 ganglion cells revealed no significant alterations in calcitonin gene-related peptide (CGRP), IB4, transient receptor potential cation channel subfamily V member 1 (TrpV1), or N52 staining across groups. Immunohistochemistry of the spinal cord revealed a localized glial response, phagocyte infiltration, and neuronal loss within the ipsilateral avulsed segment. A comparable response from glia and phagocytes was also found in the intact L4 spinal cord, supporting the role for central mechanisms within the L4-5 spinal cord in contributing to the generation of the pain-related behavior. The SRA model provides a platform to investigate possible new pharmacological treatments for avulsion injuries.
Collapse
Affiliation(s)
- Daniel J Chew
- Centre for Neuroscience and Trauma, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Newark Street, London, United Kingdom.
| | | | | | | |
Collapse
|
8
|
Song C, Zhong GB, Liu ZD, Li W, Ni PW, Qiao ZG. Effective reinnervation of the quadriceps femoris by spinal ventral root cross-anastomosis in rats. Acta Cir Bras 2012; 27:330-7. [DOI: 10.1590/s0102-86502012000500009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 04/16/2012] [Indexed: 11/21/2022] Open
Abstract
PURPOSE: To study the effective recovery of the quadriceps femoris by spinal ventral root cross-anastomosis in rats. METHODS: End-to-end anastomosis was performed between the left L1 and L3 ventral roots using autogenous nerve graft ,and the right L1 and L3 roots were left intact. In control animals, the left L3 ventral root was cut and shortened, and anastomosis was not performed. Six months postoperatively, the movement of low extremities was detected by electrophysiological examination, hindlimb locomotion and basso, beattie and bresnahan (BBB) scoring at one, three, seven, 14, 21 and 28 days after SCI. Fluorescence retrograde tracing with TRUE BLUE (TB) and HE staining were performed to observe the nerve regeneration. RESULTS: Six months after surgery, the anastomotic nerve was smooth and not atrophic. The amplitudes of action potential were 7.63±1.86 mV and 6.0±1.92 mV respectively before and after the spinal cord hemisection. The contraction of left quadriceps femoris was induced by a single stimulation of the anastomotic nerve. The locomotion of left hindlimb was partially restored after spinal cord hemisection while creeping and climbing. In addition, there was significant difference in the BBB score at one, three and seven days after SCI. TB retrograde tracing and neurophysiologic observation indicated efficient reinnervation of the quadriceps femoris. CONCLUSION: The cross-anastomosis between spinal ventral root can partially reconstruct the function of quadriceps femoris following SCI and may have clinical implication for the treatment of human SCI.
Collapse
Affiliation(s)
| | | | | | - Wei Li
- Shanghai Jiao Tong University
| | | | | |
Collapse
|
9
|
Wu L, Wu J, Chang HH, Havton LA. Selective plasticity of primary afferent innervation to the dorsal horn and autonomic nuclei following lumbosacral ventral root avulsion and reimplantation in long term studies. Exp Neurol 2011; 233:758-66. [PMID: 22178333 DOI: 10.1016/j.expneurol.2011.11.034] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 11/13/2011] [Accepted: 11/25/2011] [Indexed: 12/25/2022]
Abstract
Previous studies involving injuries to the nerves of the cauda equina and the conus medullaris have shown that lumbosacral ventral root avulsion in rat models results in denervation and dysfunction of the lower urinary tract, retrograde and progressive cell death of the axotomized motor and parasympathetic neurons, as well as the emergence of neuropathic pain. Root reimplantation has also been shown to ameliorate several of these responses, but experiments thus far have been limited to studying the effects of lesion and reimplantation local to the lumbosacral region. Here, we have expanded the region of investigation after lumbosacral ventral root avulsion and reimplantation to include the thoracolumbar sympathetic region of the spinal cord. Using a retrograde tracer injected into the major pelvic ganglion, we were able to define the levels of the spinal cord that contain sympathetic preganglionic neurons innervating the lower urinary tract. We have conducted studies on the effects of the lumbosacral ventral root avulsion and reimplantation models on the afferent innervation of the dorsal horn and autonomic nuclei at both thoracolumbar and lumbosacral levels through immunohistochemistry for the markers calcitonin gene-related peptide (CGRP) and vesicular glutamate transporter 1 (VGLUT1). Surprisingly, our experiments reveal a selective and significant decrease of CGRP-positive innervation in the dorsal horn at thoracolumbar levels that is partially restored with root reimplantation. However, no similar changes were detected at the lumbosacral levels despite the injury and repair targeting efferent neurons, and being performed at the lumbosacral levels. Despite the changes evident in the thoracolumbar dorsal horn, we find no changes in afferent innervation of the autonomic nuclei at either sympathetic or parasympathetic segmental levels by CGRP or VGLUT1. We conclude that even remote, efferent root injuries and repair procedures can have an effect on remote and non-lesioned sensory systems sharing common peripheral ganglia.
Collapse
Affiliation(s)
- Lisa Wu
- Interdepartmental Program for Neuroscience, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | | | | | | |
Collapse
|