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1.
Int J Mol Sci ; 22(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806636

RESUMO

Stem cell-based therapeutics are amongst the most promising next-generation therapeutic approaches for the treatment of spinal cord injury (SCI), as they may promote the repair or regeneration of damaged spinal cord tissues. However, preclinical optimization should be performed before clinical application to guarantee safety and therapeutic effect. Here, we investigated the optimal injection route and dose for adult human multipotent neural cells (ahMNCs) from patients with hemorrhagic stroke using an SCI animal model. ahMNCs demonstrate several characteristics associated with neural stem cells (NSCs), including the expression of NSC-specific markers, self-renewal, and multi neural cell lineage differentiation potential. When ahMNCs were transplanted into the lateral ventricle of the SCI animal model, they specifically migrated within 24 h of injection to the damaged spinal cord, where they survived for at least 5 weeks after injection. Although ahMNC transplantation promoted significant locomotor recovery, the injection dose was shown to influence treatment outcomes, with a 1 × 106 (medium) dose of ahMNCs producing significantly better functional recovery than a 3 × 105 (low) dose. There was no significant gain in effect with the 3 × 106 ahMNCs dose. Histological analysis suggested that ahMNCs exert their effects by modulating glial scar formation, neuroprotection, and/or angiogenesis. These data indicate that ahMNCs from patients with hemorrhagic stroke could be used to develop stem cell therapies for SCI and that the indirect injection route could be clinically relevant. Moreover, the optimal transplantation dose of ahMNCs defined in this preclinical study might be helpful in calculating its optimal injection dose for patients with SCI in the future.


Assuntos
Células-Tronco Multipotentes/patologia , Células-Tronco Neurais/patologia , Traumatismos da Medula Espinal/patologia , Medula Espinal/patologia , Adulto , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Humanos , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/fisiologia , Transplante de Células-Tronco/métodos
2.
Undersea Hyperb Med ; 48(1): 25-31, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33648030

RESUMO

Background: The treatment of decompression sickness (DCS) with hyperbaric oxygen (HBO2) serves to decrease intravascular bubble size, increase oxygen (O2) delivery to tissue and enhance the elimination of inert gas. Emulsified perfluorocarbons (PFC) combined with breathing O2 have been shown to have similar effects animal models. We studied an ovine model of severe DCS treated with the intravenous PFC Oxycyte™ while breathing O2 compared to saline control also breathing O2. Methods: Juvenile male sheep (N=67; weight 24.4±2.10kg) were compressed to 257 feet of sea water (fsw) in our multiple large-animal chamber where they remained under pressure for 31 minutes. Animals then were decompressed to surface pressure and randomized to receive either Oxycyte at 5mL/kg intravenously (IV) or 5mL/kg saline IV (both receiving 100% O2) 10 minutes after reaching surface pressure. Mortality was recorded at two hours, four hours, and 24 hours after receiving the study drug. Surviving animals underwent perfusion fixation and harvesting of the spinal cord at 24 hours. Spinal cord sections were assessed for volume of lesion area and compared. Results: There was no significant difference in survival at two hours (p=0.2737), four hours (p=0.2101), or 24 hours (p=0.3171). Paralysis at 24 hours was not significantly different. However, spinal cord lesion area was significantly smaller in the Oxycyte group as compared to the saline group, with median spinal cord lesion areas 0.65% vs. 0.94% (p=0.0107). Conclusion: In this ovine model of severe DCS the intravenous PFC Oxycyte did not reduce mortality but did ameliorate spinal cord injury when used after the onset of DCS.


Assuntos
Doença da Descompressão/terapia , Fluorcarbonetos/uso terapêutico , Oxigenoterapia/métodos , Traumatismos da Medula Espinal/prevenção & controle , Animais , Doença da Descompressão/complicações , Doença da Descompressão/mortalidade , Modelos Animais de Doenças , Fluorcarbonetos/administração & dosagem , Injeções Intravenosas , Masculino , Paralisia/etiologia , Distribuição Aleatória , Solução Salina/administração & dosagem , Água do Mar , Ovinos , Traumatismos da Medula Espinal/patologia , Fatores de Tempo
3.
Microbiome ; 9(1): 59, 2021 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-33678185

RESUMO

BACKGROUND: Spinal cord injury (SCI) patients display disruption of gut microbiome, and gut dysbiosis exacerbate neurological impairment in SCI models. Cumulative data support an important role of gut microbiome in SCI. Here, we investigated the hypothesis that fecal microbiota transplantation (FMT) from healthy uninjured mice into SCI mice may exert a neuroprotective effect. RESULTS: FMT facilitated functional recovery, promoted neuronal axonal regeneration, improved animal weight gain and metabolic profiling, and enhanced intestinal barrier integrity and GI motility in SCI mice. High-throughput sequencing revealed that levels of phylum Firmicutes, family Christensenellaceae, and genus Butyricimonas were reduced in fecal samples of SCI mice, and FMT remarkably reshaped gut microbiome. Also, FMT-treated SCI mice showed increased amount of fecal short-chain fatty acids (SCFAs), which correlated with alteration of intestinal permeability and locomotor recovery. Furthermore, FMT downregulated IL-1ß/NF-κB signaling in spinal cord and NF-κB signaling in gut following SCI. CONCLUSION: Our study demonstrates that reprogramming of gut microbiota by FMT improves locomotor and GI functions in SCI mice, possibly through the anti-inflammatory functions of SCFAs. Video Abstract.


Assuntos
Encéfalo/fisiologia , Transplante de Microbiota Fecal , Microbioma Gastrointestinal/fisiologia , Neuroproteção/fisiologia , Traumatismos da Medula Espinal/terapia , Animais , Ácidos Graxos Voláteis/metabolismo , Fezes/química , Feminino , Interleucina-1beta/metabolismo , Intestinos/microbiologia , Intestinos/fisiologia , Locomoção , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Transdução de Sinais , Traumatismos da Medula Espinal/patologia
4.
Int J Mol Sci ; 22(4)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670312

RESUMO

Investigating the molecular mechanisms governing developmental axon growth has been a useful approach for identifying new strategies for boosting axon regeneration after injury, with the goal of treating debilitating conditions such as spinal cord injury and vision loss. The picture emerging is that various axonal organelles are important centers for organizing the molecular mechanisms and machinery required for growth cone development and axon extension, and these have recently been targeted to stimulate robust regeneration in the injured adult central nervous system (CNS). This review summarizes recent literature highlighting a central role for organelles such as recycling endosomes, the endoplasmic reticulum, mitochondria, lysosomes, autophagosomes and the proteasome in developmental axon growth, and describes how these organelles can be targeted to promote axon regeneration after injury to the adult CNS. This review also examines the connections between these organelles in developing and regenerating axons, and finally discusses the molecular mechanisms within the axon that are required for successful axon growth.


Assuntos
Cones de Crescimento/metabolismo , Regeneração Nervosa , Organelas/metabolismo , Traumatismos da Medula Espinal , Animais , Cones de Crescimento/patologia , Humanos , Organelas/patologia , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/terapia
5.
Magn Reson Imaging ; 78: 42-51, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33556483

RESUMO

In the traumatically injured spinal cord, decreased perfusion is believed to contribute to secondary tissue damage beyond the primary mechanical impact, and restoration of perfusion is believed to be a promising therapeutic target. However, methods to monitor spinal cord perfusion non-invasively are limited. Perfusion magnetic resonance imaging (MRI) techniques established for the brain have not been routinely adopted to the spinal cord. The purpose of this study was to examine the relationship between spinal cord blood flow (SCBF) and injury severity in a rat thoracic spinal cord contusion injury (SCI) model using flow-sensitive alternating inversion recovery (FAIR) with two variants of the label position. SCBF as a marker of severity was compared to T1 mapping and to spinal cord-optimized diffusion weighted imaging (DWI) with filtered parallel apparent diffusion coefficient. Thirty-eight rats underwent a T10 contusion injury with varying severities (8 sham; 10 mild; 10 moderate; 10 severe) with MRI performed at 1 day post injury at the lesion site and follow-up neurological assessments using the Basso, Beattie, Bresnahan (BBB) locomotor scoring up to 28 days post injury. Using whole-cord regions of interest at the lesion epicenter, SCBF was decreased with injury severity and had a significant correlation with BBB scores at 28 days post injury. Importantly, estimates of arterial transit times (ATT) in the injured spinal cord were not altered after injury, which suggests that FAIR protocols optimized to measure SCBF provide more value in the context of acute traumatic injury to the cord. T1-relaxation time constants were strongly related to injury severity and had a larger extent of changes than either SCBF or DWI measures. These findings suggest that perfusion decreases in the spinal cord can be monitored non-invasively after injury, and multi-parametric MRI assessments of perfusion, diffusion, and relaxation capture unique features of the pathophysiology of preclinical injury.


Assuntos
Comportamento Animal , Hemodinâmica , Traumatismos da Medula Espinal/fisiopatologia , Medula Espinal/irrigação sanguínea , Animais , Imagem por Ressonância Magnética , Masculino , Ratos , Traumatismos da Medula Espinal/diagnóstico por imagem , Traumatismos da Medula Espinal/patologia
6.
Nat Neurosci ; 24(3): 312-325, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33589835

RESUMO

Reactive astrocytes are astrocytes undergoing morphological, molecular, and functional remodeling in response to injury, disease, or infection of the CNS. Although this remodeling was first described over a century ago, uncertainties and controversies remain regarding the contribution of reactive astrocytes to CNS diseases, repair, and aging. It is also unclear whether fixed categories of reactive astrocytes exist and, if so, how to identify them. We point out the shortcomings of binary divisions of reactive astrocytes into good-vs-bad, neurotoxic-vs-neuroprotective or A1-vs-A2. We advocate, instead, that research on reactive astrocytes include assessment of multiple molecular and functional parameters-preferably in vivo-plus multivariate statistics and determination of impact on pathological hallmarks in relevant models. These guidelines may spur the discovery of astrocyte-based biomarkers as well as astrocyte-targeting therapies that abrogate detrimental actions of reactive astrocytes, potentiate their neuro- and glioprotective actions, and restore or augment their homeostatic, modulatory, and defensive functions.


Assuntos
Envelhecimento/patologia , Astrócitos/patologia , Encéfalo/patologia , Medula Espinal/patologia , Animais , Encefalopatias/patologia , Lesões Encefálicas/patologia , Humanos , Traumatismos da Medula Espinal/patologia
7.
Brain ; 144(1): 144-161, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33578421

RESUMO

Traumatic spinal cord injury is a devastating insult followed by progressive cord atrophy and neurodegeneration. Dysregulated or non-resolving inflammatory processes can disturb neuronal homeostasis and drive neurodegeneration. Here, we provide an in-depth characterization of innate and adaptive inflammatory responses as well as oxidative tissue injury in human traumatic spinal cord injury lesions compared to non-traumatic control cords. In the lesion core, microglia were rapidly lost while intermediate (co-expressing pro- as well as anti-inflammatory molecules) blood-borne macrophages dominated. In contrast, in the surrounding rim, TMEM119+ microglia numbers were maintained through local proliferation and demonstrated a predominantly pro-inflammatory phenotype. Lymphocyte numbers were low and mainly consisted of CD8+ T cells. Only in a subpopulation of patients, CD138+/IgG+ plasma cells were detected, which could serve as candidate cellular sources for a developing humoral immunity. Oxidative neuronal cell body and axonal injury was visualized by intracellular accumulation of amyloid precursor protein (APP) and oxidized phospholipids (e06) and occurred early within the lesion core and declined over time. In contrast, within the surrounding rim, pronounced APP+/e06+ axon-dendritic injury of neurons was detected, which remained significantly elevated up to months/years, thus providing mechanistic evidence for ongoing neuronal damage long after initial trauma. Dynamic and sustained neurotoxicity after human spinal cord injury might be a substantial contributor to (i) an impaired response to rehabilitation; (ii) overall failure of recovery; or (iii) late loss of recovered function (neuro-worsening/degeneration).


Assuntos
Mielite/imunologia , Estresse Oxidativo/imunologia , Traumatismos da Medula Espinal/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Citocinas/imunologia , Feminino , Humanos , Macrófagos/imunologia , Masculino , Microglia/imunologia , Pessoa de Meia-Idade , Mielite/etiologia , Mielite/patologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/patologia
8.
BMC Complement Med Ther ; 21(1): 69, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33607999

RESUMO

BACKGROUND: Endoplasmic reticulum stress (ERS) is one of the main mechanisms of spinal cord injury (SCI) pathology and can affect the physiological state of neurons. Icariin (ICA), the main pharmacological component of Epimedium, can relieve the symptoms of patients with SCI and has obvious protective effects on neurons through ERS. METHODS: PC12 cells were induced to differentiate into neurons by nerve growth factor and identified by flow cytometry. Cell proliferation was detected by CCK8 method, cell viability was detected by SRB assay, apoptosis was detected by flow cytometry and microstructure of ER was observed by transmission electron microscope. Western blot was used to detect the protein expression of CHOP and Grp78, and qPCR was used to detect the mRNA expression of CHOP and Grp78. RESULTS: The results of CCK8, SRB and flow cytometry showed that ICA could relieve ERS and reduce apoptosis of PC12 cells. The results of transmission microscope showed that ICA could reduce apoptosis of PC12 cells caused by ERS. The results of Western blot and q-PCR showed that ICA could inhibit ERS by down-regulating the expression of CHOP and Grp78. CONCLUSIONS: ICA can inhibit ERS and promote the repair of PC12 cells by down-regulating the expression of CHOP and Grp78. ICA has the potential to promote the recovery of spinal cord injury.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Epimedium/química , Flavonoides/farmacologia , Extratos Vegetais/farmacologia , Traumatismos da Medula Espinal/patologia , Animais , Apoptose , Proteínas de Transporte/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Flavonoides/uso terapêutico , Células PC12 , Extratos Vegetais/uso terapêutico , Ratos , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/metabolismo , Fator de Transcrição CHOP/metabolismo
9.
Turk Neurosurg ; 31(1): 93-98, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33491171

RESUMO

AIM: To examine the effect of propolis on the healing process in terms of both electrophysiological and ultrastructural parameters in a rat model of experimental spinal cord injury. MATERIAL AND METHODS: Thirty rats were divided into control, spinal cord trauma, and treated trauma groups with 10 rats per group. The rats were sacrificed after 10 days. Before sacrifice, all rats were neurologically assessed by electrophysiological monitoring, and immediately after sacrifice, the spinal cord was examined ultrastructurally by transmission electron microscopy (TEM). RESULTS: According to the electrophysiological examination, the treatment group was statistically significantly different from the trauma group. However, no statistically significant difference was found between the control and treatment groups. In terms of the TEM examination, the treatment group was significantly different from the trauma group. CONCLUSION: In this study, propolis was administered just before the induction of trauma, and the findings suggest that the use of propolis has a positive effect on the healing process. This implies that in order to prevent postoperative deficits, this treatment may be preferably applied before spinal cord surgery for trauma.


Assuntos
Própole/uso terapêutico , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/tratamento farmacológico , Medula Espinal/efeitos dos fármacos , Animais , Masculino , Própole/farmacologia , Ratos , Ratos Wistar , Recuperação de Função Fisiológica/fisiologia , Medula Espinal/patologia , Medula Espinal/ultraestrutura , Traumatismos da Medula Espinal/patologia , Resultado do Tratamento
10.
Cell Prolif ; 54(3): e12992, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33506613

RESUMO

Spinal cord injury (SCI) always leads to functional deterioration due to a series of processes including cell death. In recent years, programmed cell death (PCD) is considered to be a critical process after SCI, and various forms of PCD were discovered in recent years, including apoptosis, necroptosis, autophagy, ferroptosis, pyroptosis and paraptosis. Unlike necrosis, PCD is known as an active cell death mediated by a cascade of gene expression events, and it is crucial for elimination unnecessary and damaged cells, as well as a defence mechanism. Therefore, it would be meaningful to characterize the roles of PCD to not only enhance our understanding of the pathophysiological processes, but also improve functional recovery after SCI. This review will summarize and explore the most recent advances on how apoptosis, necroptosis, autophagy, ferroptosis, pyroptosis and paraptosis are involved in SCI. This review can help us to understand the various functions of PCD in the pathological processes of SCI, and contribute to our novel understanding of SCI of unknown aetiology in the near future.


Assuntos
Apoptose/genética , Morte Celular/efeitos dos fármacos , Necrose/tratamento farmacológico , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Autofagia/efeitos dos fármacos , Morte Celular/fisiologia , Humanos , Necroptose/efeitos dos fármacos , Necrose/metabolismo , Traumatismos da Medula Espinal/patologia
11.
J Neurosci ; 41(5): 845-854, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33472820

RESUMO

Spinal interneurons are important facilitators and modulators of motor, sensory, and autonomic functions in the intact CNS. This heterogeneous population of neurons is now widely appreciated to be a key component of plasticity and recovery. This review highlights our current understanding of spinal interneuron heterogeneity, their contribution to control and modulation of motor and sensory functions, and how this role might change after traumatic spinal cord injury. We also offer a perspective for how treatments can optimize the contribution of interneurons to functional improvement.


Assuntos
Interneurônios/metabolismo , Doenças do Sistema Nervoso/metabolismo , Plasticidade Neuronal/fisiologia , Traumatismos da Medula Espinal/metabolismo , Medula Espinal/metabolismo , Animais , Agonistas GABAérgicos/farmacologia , Agonistas GABAérgicos/uso terapêutico , Humanos , Interneurônios/efeitos dos fármacos , Interneurônios/patologia , Doenças do Sistema Nervoso/tratamento farmacológico , Doenças do Sistema Nervoso/patologia , Plasticidade Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/patologia
12.
Int J Mol Sci ; 22(2)2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33451043

RESUMO

Our aim was to investigate the subset distribution and function of circulating monocytes, proinflammatory cytokine levels, gut barrier damage, and bacterial translocation in chronic spinal cord injury (SCI) patients. Thus, 56 SCI patients and 28 healthy donors were studied. The levels of circulating CD14+highCD16-, CD14+highCD16+, and CD14+lowCD16+ monocytes, membrane TLR2, TLR4, and TLR9, phagocytic activity, ROS generation, and intracytoplasmic TNF-α, IL-1, IL-6, and IL-10 after lipopolysaccharide (LPS) stimulation were analyzed by polychromatic flow cytometry. Serum TNF-α, IL-1, IL-6 and IL-10 levels were measured by Luminex and LPS-binding protein (LBP), intestinal fatty acid-binding protein (I-FABP) and zonulin by ELISA. SCI patients had normal monocyte counts and subset distribution. CD14+highCD16- and CD14+highCD16+ monocytes exhibited decreased TLR4, normal TLR2 and increased TLR9 expression. CD14+highCD16- monocytes had increased LPS-induced TNF-α but normal IL-1, IL-6, and IL-10 production. Monocytes exhibited defective phagocytosis but normal ROS production. Patients had enhanced serum TNF-α and IL-6 levels, normal IL-1 and IL-10 levels, and increased circulating LBP, I-FABP, and zonulin levels. Chronic SCI patients displayed impaired circulating monocyte function. These patients exhibited a systemic proinflammatory state characterized by enhanced serum TNF-α and IL-6 levels. These patients also had increased bacterial translocation and gut barrier damage.


Assuntos
Suscetibilidade a Doenças , Inflamação/complicações , Enteropatias/complicações , Traumatismos da Medula Espinal/etiologia , Traumatismos da Medula Espinal/metabolismo , Adulto , Biomarcadores , Estudos de Casos e Controles , Doença Crônica , Citocinas/metabolismo , Feminino , Homeostase , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Monócitos/imunologia , Monócitos/metabolismo , Fagócitos/imunologia , Fagócitos/metabolismo , Fagocitose , Índice de Gravidade de Doença , Traumatismos da Medula Espinal/patologia , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem
13.
Biomed Pharmacother ; 134: 111168, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33395598

RESUMO

Axonal demyelination is a consistent pathological characteristic of Spinal cord injury (SCI). Promoting differentiation of oligodendrocytes is of importance for remyelination. Conversion of reactive astrocytes with stem cell potential to oligodendrocytes is proposed as an innovative strategy for SCI repair. Neuregulin-1 (Nrg1) plays an essential role in the differentiation of oligodendrocytes. Therefore, it's a potential treatment for demyelination in SCI that using Nrg1 to drive reactive astrocytes toward oligodendrocyte lineage cells. In this study, tumor necrosis factor-α (TNF-α) was used to induce dedifferentiation of primary rat spinal cord astrocytes into reactive astrocytes and Nrg1 was used to induce astrocytes in vitro and in vivo. The results showed that astrocytes treated with TNF-α expressed immaturity markers CD44 and Musashi1 at mRNA and protein levels, indicating that TNF-α induced the stem cell state of astrocytes. Nrg1 induced reactive astrocytes to express oligodendrocyte markers PDGFR-α and O4 at mRNA and protein levels, indicating that Nrg1 directly converts reactive astrocytes toward oligodendrocyte lineage cells. Moreover, upregulation of PI3K-AKT-mTOR signaling activation in response to Nrg1 was observed. In rats with SCI, intrathecal treatment with Nrg1 converted reactive astrocytes to oligodendrocyte lineage cells, inhibited astrogliosis, promoted remyelination, protected axons and eventually improved BBB score. All the biological effects of Nrg1 were significantly reversed by the co-administration of Nrg1 and ErbB inhibitor, suggesting that Nrg1 functioned through the receptor ErbB. Our findings indicate that Nrg1 is sufficient to trans-differentiate reactive astrocytes to oligodendrocytes via the PI3K-AKT-mTOR signaling pathway and repair SCI. Delivery of Nrg1 for the remyelination processes could be a promising strategy for spinal cord repair.


Assuntos
Astrócitos/efeitos dos fármacos , Linhagem da Célula , Transdiferenciação Celular/efeitos dos fármacos , Neuregulina-1/farmacologia , Oligodendroglia/efeitos dos fármacos , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Traumatismos da Medula Espinal/tratamento farmacológico , Medula Espinal/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Animais , Astrócitos/enzimologia , Astrócitos/patologia , Células Cultivadas , Modelos Animais de Doenças , Receptores ErbB/metabolismo , Feminino , Bainha de Mielina/metabolismo , Oligodendroglia/enzimologia , Oligodendroglia/patologia , Ratos Sprague-Dawley , Transdução de Sinais , Medula Espinal/enzimologia , Medula Espinal/patologia , Traumatismos da Medula Espinal/enzimologia , Traumatismos da Medula Espinal/patologia , Fator de Necrose Tumoral alfa/farmacologia
14.
Methods Mol Biol ; 2225: 227-239, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33108666

RESUMO

Severe inflammatory disease initiated by neurotrauma and stroke is of primary concern in these intractable pathologies as noted in recent studies and understanding of the pathogenesis of spinal cord injury (SCI) in the rat model. Successful anti-inflammatory treatments should result in neuroprotection and limit the loss of neurological function to injury caused by the initial damage. Continuous subdural infusion offers direct access to the cavity of injury (COI) that forms after balloon crush SCI deep in the spinal cord. Some anti-inflammatory compounds are not likely capable of crossing the blood-spinal cord barrier. Subdural infusion of myxoma virus-derived Serp-1, an anti-thrombotic/anti-thrombolytic, and also of M-T7, a chemokine inhibitor, improved the locomotor scores and pain sensation scores as well as reduced the numbers of macrophages in the COI by 50 and 80%, respectively, while intraperitoneal infusion of either protein had little effect. Injection of a chitosan hydrogel loaded with Serp-1 into the dorsal spinal column crush also resulted in improved neurological deficits and in reduction of the size of the crush lesion 4 weeks after injury. While neurological scores in a simplified hind-end (HE) locomotor test together with a toe-pinch withdrawal test demonstrated improvement in all balloon crush injury and dorsal spinal crush injury rats, a severe inflammation is induced by the injury indicating additional damage to the spinal cord. Thus neurological function testing can be contradictory, rather than corresponding, to the pathogenesis of SCI. The count of macrophages in the COI offers a precise, reliable method of measuring the effectiveness of a neuroprotective treatment of SCI in preclinical studies.


Assuntos
Anti-Inflamatórios/farmacologia , Fatores Imunológicos/farmacologia , Myxoma virus/química , Fármacos Neuroprotetores/farmacologia , Traumatismos da Medula Espinal/tratamento farmacológico , Proteínas Virais/farmacologia , Animais , Anti-Inflamatórios/imunologia , Quitosana/química , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos/métodos , Hidrogéis/química , Fatores Imunológicos/imunologia , Injeções Epidurais , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Atividade Motora/efeitos dos fármacos , Fármacos Neuroprotetores/imunologia , Ratos , Ratos Long-Evans , Receptores de Interferon/imunologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/imunologia , Medula Espinal/patologia , Traumatismos da Medula Espinal/imunologia , Traumatismos da Medula Espinal/patologia , Proteínas Virais/imunologia
15.
Sci Rep ; 10(1): 22414, 2020 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-33376249

RESUMO

Spinal cord injury results in irreversible tissue damage followed by a very limited recovery of function. In this study we investigated whether transplantation of undifferentiated human induced pluripotent stem cells (hiPSCs) into the injured rat spinal cord is able to induce morphological and functional improvement. hiPSCs were grafted intraspinally or intravenously one week after a thoracic (T11) spinal cord contusion injury performed in Fischer 344 rats. Grafted animals showed significantly better functional recovery than the control rats which received only contusion injury. Morphologically, the contusion cavity was significantly smaller, and the amount of spared tissue was significantly greater in grafted animals than in controls. Retrograde tracing studies showed a statistically significant increase in the number of FB-labeled neurons in different segments of the spinal cord, the brainstem and the sensorimotor cortex. The extent of functional improvement was inversely related to the amount of chondroitin-sulphate around the cavity and the astrocytic and microglial reactions in the injured segment. The grafts produced GDNF, IL-10 and MIP1-alpha for at least one week. These data suggest that grafted undifferentiated hiPSCs are able to induce morphological and functional recovery after spinal cord contusion injury.


Assuntos
Células-Tronco Pluripotentes Induzidas/metabolismo , Traumatismos da Medula Espinal , Nicho de Células-Tronco , Transplante de Células-Tronco , Animais , Quimiocina CCL3/metabolismo , Modelos Animais de Doenças , Feminino , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Xenoenxertos , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Células-Tronco Pluripotentes Induzidas/transplante , Interleucina-10/metabolismo , Ratos , Ratos Endogâmicos F344 , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/terapia
16.
J Vis Exp ; (166)2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33369603

RESUMO

Spinal cord injury is a devastating complication of aortic repair. Despite developments for the prevention and treatment of spinal cord injury, its incidence is still considerably high and therefore, influences patient outcome. Microcirculation plays a key role in tissue perfusion and oxygen supply and is often dissociated from macrohemodynamics. Thus, direct evaluation of spinal cord microcirculation is essential for the development of microcirculation-targeted therapies and the evaluation of existing approaches in regard to spinal cord microcirculation. However, most of the methods do not provide real-time assessment of spinal cord microcirculation. The aim of this study is to describe a standardized protocol for real-time spinal cord microcirculatory evaluation using laser-Doppler needle probes directly inserted in the spinal cord. We used a porcine model of ischemia/reperfusion to induce deterioration of the spinal cord microcirculation. In addition, a fluorescent microsphere injection technique was used. Initially, animals were anesthetized and mechanically ventilated. Thereafter, laser-Doppler needle probe insertion was performed, followed by the placement of cerebrospinal fluid drainage. A median sternotomy was performed for exposure of the descending aorta to perform aortic cross-clamping. Ischemia/reperfusion was induced by supra-celiac aortic cross-clamping for a total of 48 min, followed by reperfusion and hemodynamic stabilization. Laser-Doppler Flux was performed in parallel with macrohemodynamic evaluation. In addition, automated cerebrospinal fluid drainage was used to maintain a stable cerebrospinal pressure. After completion of the protocol, animals were sacrificed, and the spinal cord was harvested for histopathological and microsphere analysis. The protocol reveals the feasibility of spinal cord microperfusion measurements using laser-Doppler probes and shows a marked decrease during ischemia as well as recovery after reperfusion. Results showed comparable behavior to fluorescent microsphere evaluation. In conclusion, this new protocol might provide a useful large animal model for future studies using real-time spinal cord microperfusion assessment in ischemia/reperfusion conditions.


Assuntos
Traumatismo por Reperfusão/patologia , Traumatismos da Medula Espinal/patologia , Isquemia do Cordão Espinal/patologia , Medula Espinal/patologia , Animais , Aorta/cirurgia , Modelos Animais de Doenças , Feminino , Hemodinâmica , Masculino , Microcirculação , Medula Espinal/irrigação sanguínea , Suínos
17.
Int J Nanomedicine ; 15: 10113-10125, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33363370

RESUMO

Background: The excess production of reactive oxygen species (ROS) after traumatic spinal cord injury (TSCI) has been identified as a leading cause of secondary injury, which can significantly exacerbate acute damage in the injured spinal cord. Thus, scavenging of ROS has emerged as an effective route to ameliorate secondary spinal cord injury. Purpose: Selenium-doped carbon quantum dots (Se-CQDs) with the ability to scavenge reactive oxygen species were prepared and used for efficiently ameliorating secondary injury in TSCI. Methods: Water-soluble Se-CQDs were easily synthesized via hydrothermal treatment of l-selenocystine. The chemical structure, size, and morphology of the Se-CQDs were characterized in detail. The biocompatibility and protective effects of the Se-CQDs against H2O2-induced oxidative damage were investigated in vitro. Moreover, the behavioral test, bladder function, histological observation, Western blot were used to investigate the neuroprotective effect of Se-CQDs in a rat model of contusion TSCI. Results: The obtained Se-CQDs exhibited good biocompatibility and remarkable protective effect against H2O2-induced oxidative damage in astrocytes and PC12 cells. Moreover, Se-CQDs displayed marked anti-inflammatory and anti-apoptotic activities, which thereby reduced the formation of glial scars and increased the survival of neurons with unscathed myelin sheaths in vivo. As a result, Se-CQDs were capable of largely improving locomotor function of rats with TSCI. Conclusion: This study suggests that Se-CQDs can be used as a promising therapeutic platform for ameliorating secondary injury in TSCI.


Assuntos
Carbono/química , Pontos Quânticos/química , Espécies Reativas de Oxigênio/metabolismo , Selênio/farmacologia , Traumatismos da Medula Espinal/patologia , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Modelos Animais de Doenças , Feminino , Camundongos , Atividade Motora/efeitos dos fármacos , Neuroglia/efeitos dos fármacos , Neuroglia/patologia , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Células PC12 , Pontos Quânticos/ultraestrutura , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/fisiopatologia
18.
Nat Commun ; 11(1): 5209, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060602

RESUMO

Chronic high-thoracic and cervical spinal cord injury (SCI) results in a complex phenotype of cardiovascular consequences, including impaired left ventricular (LV) contractility. Here, we aim to determine whether such dysfunction manifests immediately post-injury, and if so, whether correcting impaired contractility can improve spinal cord oxygenation (SCO2), blood flow (SCBF) and metabolism. Using a porcine model of T2 SCI, we assess LV end-systolic elastance (contractility) via invasive pressure-volume catheterization, monitor intraparenchymal SCO2 and SCBF with fiberoptic oxygen sensors and laser-Doppler flowmetry, respectively, and quantify spinal cord metabolites with microdialysis. We demonstrate that high-thoracic SCI acutely impairs cardiac contractility and substantially reduces SCO2 and SCBF within the first hours post-injury. Utilizing the same model, we next show that augmenting LV contractility with the ß-agonist dobutamine increases SCO2 and SCBF more effectively than vasopressor therapy, whilst also mitigating increased anaerobic metabolism and hemorrhage in the injured cord. Finally, in pigs with T2 SCI survived for 12 weeks post-injury, we confirm that acute hemodynamic management with dobutamine appears to preserve cardiac function and improve hemodynamic outcomes in the chronic setting. Our data support that cardio-centric hemodynamic management represents an advantageous alternative to the current clinical standard of vasopressor therapy for acute traumatic SCI.


Assuntos
Coração/fisiopatologia , Hemodinâmica/fisiologia , Hemorragia/fisiopatologia , Fenômenos Fisiológicos Respiratórios , Traumatismos da Medula Espinal/fisiopatologia , Medula Espinal/fisiopatologia , Animais , Modelos Animais de Doenças , Dobutamina/farmacologia , Feminino , Fluxometria por Laser-Doppler , Chaperonas Moleculares/metabolismo , Norepinefrina/farmacologia , Fluxo Sanguíneo Regional/fisiologia , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/patologia , Suínos , Disfunção Ventricular Esquerda/tratamento farmacológico , Disfunção Ventricular Esquerda/fisiopatologia
19.
PLoS One ; 15(8): e0236470, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32750057

RESUMO

OBJECTIVES: Spinal cord injury (SCI) is associated with severe autonomic dysfunction. Patients with SCI often suffer from a lack of central nervous system control over the gastrointestinal system. Therefore, we hypothesized that patients with SCI would cause intestinal flora imbalance. We investigated alterations in the fecal microbiome in a group of patients with SCI. METHODS: Microbial communities in the feces of 23 patients and 23 healthy controls were investigated using high-throughput Illumina Miseq sequencing targeting the V3-V4 region of the 16S ribosomal RNA (rRNA) gene. The relative abundances between the fecal microbiota at the genus level in patients with SCI and healthy individuals were determined using cluster analysis. RESULTS: The structure and quantity of fecal microbiota differed significantly between patients with SCI and healthy controls, but the richness and diversity were not significantly different. A two-dimensional heatmap showed that the relative abundances of forty-five operational taxonomic units (OTUs) were significantly enriched either in SCI or healthy samples. Among these, 18 OTUs were more abundant in healthy controls than in patients with SCI, and 27 OTUs were more abundant in the SCI group than in healthy controls. CONCLUSION: Our study showed that patients with SCI exhibited microbiome dysbiosis.


Assuntos
Disbiose/microbiologia , Fezes/microbiologia , Microbiota/genética , Traumatismos da Medula Espinal/microbiologia , Adulto , Bactérias/classificação , Bactérias/genética , Disbiose/genética , Disbiose/patologia , Feminino , Microbioma Gastrointestinal/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Filogenia , RNA Ribossômico 16S/genética , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/patologia
20.
J Vis Exp ; (160)2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32628176

RESUMO

We describe the implementation of spinal cord injury in mice to elicit detrusor-sphincter dyssynergia, a functional bladder outlet obstruction, and subsequent bladder wall remodeling. To facilitate assessment of the cellular composition of the bladder wall in non-injured control and spinal cord injured mice, we developed an optimized dissociation protocol that supports high cell viability and enables the detection of discrete subpopulations by flow cytometry. Spinal cord injury is created by complete transection of the thoracic spinal cord. At the time of tissue harvest, the animal is perfused with phosphate-buffered saline under deep anesthesia and bladders are harvested into Tyrode's buffer. Tissues are minced prior to incubation in digestion buffer that has been optimized based on the collagen content of mouse bladder as determined by interrogation of publicly available gene expression databases. Following generation of a single cell suspension, material is analyzed by flow cytometry for assessment of cell viability, cell number and specific subpopulations. We demonstrate that the method yields cell populations with greater than 90% viability, and robust representation of cells of mesenchymal and epithelial origin. This method will enable accurate downstream analysis of discrete cell types in mouse bladder and potentially other organs.


Assuntos
Separação Celular/métodos , Traumatismos da Medula Espinal/patologia , Bexiga Urinária/patologia , Animais , Calibragem , Sobrevivência Celular , Análise de Dados , Matriz Extracelular/metabolismo , Feminino , Citometria de Fluxo , Camundongos , Perfusão , Traumatismos da Medula Espinal/cirurgia , Transcriptoma/genética
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