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1.
Exp Neurol ; 351: 113987, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35065054

RESUMO

Traumatic brain injury (TBI) is a major cause of disability and death. Mild TBI (mTBI) constitutes ~75% of all TBI cases. Repeated exposure to mTBI (rmTBI), leads to the exacerbation of the symptoms compared to single mTBI. To date, there is no FDA-approved drug for TBI or rmTBI. This research aims to investigate possible rmTBI neurotherapy by targeting TBI pathology-related mechanisms. Oxidative stress is partly responsible for TBI/rmTBI neuropathologic outcomes. Thus, targeting oxidative stress may ameliorate TBI/rmTBI consequences. In this study, we hypothesized that mitoquinone (MitoQ), a mitochondria-targeted antioxidant, would ameliorate TBI/rmTBI associated pathologic features by mitigating rmTBI-induced oxidative stress. To model rmTBI, C57BL/6 mice were subjected to three concussive head injuries. MitoQ (5 mg/kg) was administered intraperitoneally to rmTBI+MitoQ mice twice per week over one month. Behavioral and cognitive outcomes were assessed, 30 days following the first head injury, using a battery of behavioral tests. Immunofluorescence was used to assess neuroinflammation and neuronal integrity. Also, qRT-PCR was used to evaluate the expression levels of antioxidant enzymes. Our findings indicated that MitoQ alleviated fine motor function and learning impairments caused by rmTBI. Mechanistically, MitoQ reduced astrocytosis, microgliosis, dendritic and axonal shearing, and increased the expression of antioxidant enzymes. MitoQ administration following rmTBI may represent an efficient approach to ameliorate rmTBI neurological and cellular outcomes with no observable side effects.


Assuntos
Concussão Encefálica , Lesões Encefálicas Traumáticas , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Concussão Encefálica/complicações , Concussão Encefálica/tratamento farmacológico , Concussão Encefálica/patologia , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/tratamento farmacológico , Suplementos Nutricionais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Compostos Organofosforados , Estresse Oxidativo , Ubiquinona/análogos & derivados
2.
J Neurotrauma ; 38(16): 2323-2334, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-33544034

RESUMO

Mitochondrial dysfunction is a pivotal target for neuroprotection strategies for traumatic brain injury (TBI). However, comprehensive time-course evaluations of mitochondrial dysfunction are lacking in the pre-clinical penetrating TBI (PTBI) model. The current study was designed to characterize temporal responses of mitochondrial dysfunction from 30 min to 2 weeks post-injury after PTBI. Anesthetized adult male rats were subjected to either PTBI or sham craniectomy (n = 6 animals per group × 7 time points). Animals were euthanized at 30 min, 3 h, 6 h, 24 h, 3 days, 7 days, and 14 days post-PTBI, and mitochondria were isolated from the ipsilateral hemisphere of brain regions near the injury core (i.e., frontal cortex [FC] and striatum [ST]) and a more distant region from the injury core (i.e., hippocampus [HIP]). Mitochondrial bioenergetics parameters were measured in real time using the high-throughput procedures of the Seahorse Flux Analyzer (Agilent Technologies, Santa Clara, CA). The post-injury time course of FC + ST showed a biphasic mitochondrial bioenergetics dysfunction response, indicative of reduced adenosine triphosphate synthesis rate and maximal respiratory capacity after PTBI. An initial phase of energy crisis was detected at 30 min (-42%; p < 0.05 vs. sham), which resolved to baseline levels between 3 and 6 h (non-significant vs. sham). This was followed by a second and more robust phase of bioenergetics dysregulation detected at 24 h that remained unresolved out to 14 days post-injury (-55% to -90%; p < 0.05 vs. sham). In contrast, HIP mitochondria showed a delayed onset of mitochondrial dysfunction at 7 days (-74%; p < 0.05 vs. sham) that remained evident out to 14 days (-51%; p < 0.05 vs. sham) post-PTBI. Collectively, PTBI-induced mitochondrial dysfunction responses were time and region specific, evident differentially at the injury core and distant region of PTBI. The current results provide the basis that mitochondrial dysfunction may be targeted differentially based on region specificity post-PTBI. Even more important, these results suggest that therapeutic interventions targeting mitochondrial dysfunction may require extended dosing regimens to achieve clinical efficacy after TBI.


Assuntos
Lesões Encefálicas Traumáticas/metabolismo , Metabolismo Energético/fisiologia , Traumatismos Cranianos Penetrantes/metabolismo , Mitocôndrias/fisiologia , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
3.
Glob Adv Health Med ; 8: 2164956119880143, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632842

RESUMO

PURPOSE: Acupressure and therapeutic touch may be beneficial for symptom management and increasing general well-being for children undergoing cancer treatment. Acupressure has the benefit of stimulating targeted acupuncture points while providing therapeutic touch. We sought to explore the relationship between acupressure and the experience of well-being among children being treated for cancer who received acupressure. METHODS: In the Acupressure for Children in Treatment for a Childhood Cancer trial, hospitalized children received acupressure using specified acupressure points for symptom control as well as points for general well-being. Acupressure was delivered by professionals and by caregivers, following training by the professional. Qualitative data were collected through semistructured interviews with a purposive sample of professional acupressure providers (n = 3) and primary caregivers (n = 13), combined with participant observation during the acupressure intervention. Data were analyzed using grounded theory methods. RESULTS: Analysis of provider interview, caregiver interview, and participation observation yielded 3 prominent themes: (1) well-being elicited by acupressure, (2) well-being elicited by touch, and (3) well-being experienced as relational and intersubjective. These themes, taken together, illustrate the intricate ways in which an intervention like acupressure can help alleviate the difficulties of a childhood cancer illness experience by promoting well-being in the child as well as the caregiver. Acupressure brought symptom relief, physical relaxation, and comforting touch to the child, allowing the caregiver to also feel relief and relaxation as caregiver-child experience of well-being are closely intertwined. CONCLUSIONS: Data from the 3 sources provided distinct and overlapping insights suggesting the versatile benefits of acupressure in promoting well-being during childhood cancer treatment. Professional acupressure combined with training of caregivers for childhood cancer may be a relational intervention that facilitates the experience of well-being for both the caregiver and the child.

4.
Glob Adv Health Med ; 8: 2164956119870444, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31453017

RESUMO

BACKGROUND: We describe the study design and protocol of a pragmatic randomized controlled trial (RCT) Acupressure for Children in Treatment for a Childhood Cancer (ACT-CC). OBJECTIVE: To describe the feasibility and effectiveness of an acupressure intervention to decrease treatment-related symptoms in children in treatment for cancer or recipients of a chemotherapy-based hematopoietic stem cell transplant (HSCT). DESIGN: Two-armed RCTs with enrollment of 5 to 30 study days. SETTING: Two pediatric teaching hospitals. PATIENTS: Eighty-five children receiving cancer treatment or a chemotherapy-based HSCT each with 1 parent or caregiver. INTERVENTION: Patients are randomized 1:1 to receive either usual care plus daily professional acupressure and caregiver delivered acupressure versus usual care alone for symptom management. Participants receive up to 20 professional treatments. MAIN OUTCOME: A composite nausea/vomiting measure for the child. SECONDARY OUTCOMES: Child's nausea, vomiting, pain, fatigue, depression, anxiety, and positive affect. PARENT OUTCOMES: Depression, anxiety, posttraumatic stress symptoms, caregiver self-efficacy, and positive affect. Feasibility of delivering the semistandardized intervention will be described. Linear mixed models will be used to compare outcomes between arms in children and parents, allowing for variability in diagnosis, treatment, and age. DISCUSSION: Trial results could help childhood cancer and HSCT treatment centers decide about the regular inclusion of trained acupressure providers to support symptom management.

5.
J Neurotrauma ; 36(2): 348-359, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29987972

RESUMO

Glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase (UCH-L1), markers of glial and neuronal cell body injury, respectively, have been previously selected by the Operation Brain Trauma Therapy (OBTT) pre-clinical therapy and biomarker screening consortium as drug development tools. However, traumatic axonal injury (TAI) also represents a major consequence and determinant of adverse outcomes after traumatic brain injury (TBI). Thus, biomarkers capable of assessing TAI are much needed. Neurofilaments (NFs) are found exclusively in axons. Here, we evaluated phospho-neurofilament-H (pNF-H) protein as a possible new TAI marker in serum and cerebrospinal fluid (CSF) across three rat TBI models in studies carried out by the OBTT consortium, namely, controlled cortical impact (CCI), parasagittal fluid percussion (FPI), and penetrating ballistics-like brain injury (PBBI). We indeed found that CSF and serum pNF-H levels are robustly elevated by 24 h post-injury in all three models. Further, in previous studies by OBTT, levetiracetam showed the most promising benefits, whereas nicotinamide showed limited benefit only at high dose (500 mg/kg). Thus, serum samples from the same repository collected by OBTT were evaluated. Treatment with 54 mg/kg intravenously of levetiracetam in the CCI model and 170 mg/kg in the PBBI model significantly attenuated pNF-H levels at 24 h post-injury as compared to respective vehicle groups. In contrast, nicotinamide (50 or 500 mg/kg) showed no reduction of pNF-H levels in CCI or PBBI models. Our current study suggests that pNF-H is a useful theranostic blood-based biomarker for TAI across different rodent TBI models. In addition, our data support levetiracetam as the most promising TBI drug candidate screened by OBTT to date.


Assuntos
Biomarcadores/sangue , Lesões Encefálicas Traumáticas/sangue , Proteínas de Neurofilamentos/sangue , Animais , Biomarcadores/líquido cefalorraquidiano , Lesões Encefálicas Traumáticas/líquido cefalorraquidiano , Modelos Animais de Doenças , Levetiracetam/farmacologia , Proteínas de Neurofilamentos/líquido cefalorraquidiano , Niacinamida/farmacologia , Nootrópicos/farmacologia , Ratos , Ratos Sprague-Dawley , Nanomedicina Teranóstica/métodos , Complexo Vitamínico B/farmacologia
6.
Methods Mol Biol ; 1462: 597-610, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27604740

RESUMO

Mitochondrial dysfunction is one of the key posttraumatic neuropathological events observed in various experimental models of traumatic brain injury (TBI). The extent of mitochondrial dysfunction has been associated with the severity and time course of secondary injury following brain trauma. Critically, several mitochondrial targeting preclinical drugs used in experimental TBI models have shown improved mitochondrial bioenergetics, together with cortical tissue sparing and cognitive behavioral outcome. Mitochondria, being a central regulator of cellular metabolic pathways and energy producer of cells, are of a great interest for researchers aiming to adopt cutting-edge methodology for mitochondrial bioenergetics assessment. The traditional way of mitochondrial bioenergetics analysis utilizing a Clark-type oxygen electrode (aka. oxytherm) is time-consuming and labor-intensive. In the present chapter, we describe an advanced and high-throughput method for mitochondrial bioenergetics assessments utilizing the Seahorse Biosciences XF(e)24 Flux Analyzer. This allows for simultaneous measurement of multiple samples with higher efficiency than the oxytherm procedure. This chapter provides helpful guidelines for conducting mitochondrial isolation and studying mitochondrial bioenergetics in brain tissue homogenates following experimental TBI.


Assuntos
Metabolismo Energético , Ensaios de Triagem em Larga Escala , Mitocôndrias/metabolismo , Traumatismos do Sistema Nervoso/etiologia , Traumatismos do Sistema Nervoso/metabolismo , Animais , Respiração Celular/efeitos dos fármacos , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Masculino , Metabolômica/métodos , Mitocôndrias/efeitos dos fármacos , Fosforilação Oxidativa , Ratos , Espécies Reativas de Oxigênio/metabolismo , Traumatismos do Sistema Nervoso/tratamento farmacológico
7.
J Neurotrauma ; 33(6): 513-22, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26439468

RESUMO

Traumatic brain injury (TBI) was the signature injury in both the Iraq and Afghan wars and the magnitude of its importance in the civilian setting is finally being recognized. Given the scope of the problem, new therapies are needed across the continuum of care. Few therapies have been shown to be successful. In severe TBI, current guidelines-based acute therapies are focused on the reduction of intracranial hypertension and optimization of cerebral perfusion. One factor considered important to the failure of drug development and translation in TBI relates to the recognition that TBI is extremely heterogeneous and presents with multiple phenotypes even within the category of severe injury. To address this possibility and attempt to bring the most promising therapies to clinical trials, we developed Operation Brain Trauma Therapy (OBTT), a multicenter, pre-clinical drug screening consortium for acute therapies in severe TBI. OBTT was developed to include a spectrum of established TBI models at experienced centers and assess the effect of promising therapies on both conventional outcomes and serum biomarker levels. In this review, we outline the approach to TBI modeling, evaluation of therapies, drug selection, and biomarker assessments for OBTT, and provide a framework for reports in this issue on the first five therapies evaluated by the consortium.


Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Animais , Biomarcadores , Modelos Animais de Doenças , Humanos
8.
J Neurotrauma ; 33(6): 523-37, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26670792

RESUMO

Nicotinamide (vitamin B3) was the first drug selected for cross-model testing by the Operation Brain Trauma Therapy (OBTT) consortium based on a compelling record of positive results in pre-clinical models of traumatic brain injury (TBI). Adult male Sprague-Dawley rats were exposed to either moderate fluid percussion injury (FPI), controlled cortical impact injury (CCI), or penetrating ballistic-like brain injury (PBBI). Nicotinamide (50 or 500 mg/kg) was delivered intravenously at 15 min and 24 h after injury with subsequent behavioral, biomarker, and histopathological outcome assessments. There was an intermediate effect on balance beam performance with the high (500 mg/kg) dose in the CCI model, but no significant therapeutic benefit was detected on any other motor task across the OBTT TBI models. There was an intermediate benefit on working memory with the high dose in the FPI model. A negative effect of the low (50 mg/kg) dose, however, was observed on cognitive outcome in the CCI model, and no cognitive improvement was observed in the PBBI model. Lesion volume analysis showed no treatment effects after either FPI or PBBI, but the high dose of nicotinamide resulted in significant tissue sparing in the CCI model. Biomarker assessments included measurements of glial fibrillary acidic protein (GFAP) and ubiquitin carboxyl-terminal hydrolase-1 (UCH-L1) in blood at 4 or 24 h after injury. Negative effects (both doses) were detected on biomarker levels of GFAP after FPI and on biomarker levels of UCH-L1 after PBBI. The high dose of nicotinamide, however, reduced GFAP levels after both PBBI and CCI. Overall, our results showed a surprising lack of benefit from the low dose nicotinamide. In contrast, and partly in keeping with the literature, some benefit was achieved with the high dose. The marginal benefits achieved with nicotinamide, however, which appeared sporadically across the TBI models, has reduced enthusiasm for further investigation by the OBTT Consortium.


Assuntos
Lesões Encefálicas Traumáticas , Niacinamida/administração & dosagem , Recuperação de Função Fisiológica/efeitos dos fármacos , Complexo Vitamínico B/administração & dosagem , Animais , Biomarcadores/sangue , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Proteína Glial Fibrilar Ácida/sangue , Masculino , Ratos , Ratos Sprague-Dawley , Ubiquitina Tiolesterase/sangue
9.
J Neurotrauma ; 33(6): 606-14, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26671284

RESUMO

Operation Brain Trauma Therapy (OBTT) is a fully operational, rigorous, and productive multicenter, pre-clinical drug and circulating biomarker screening consortium for the field of traumatic brain injury (TBI). In this article, we synthesize the findings from the first five therapies tested by OBTT and discuss both the current work that is ongoing and potential future directions. Based on the results generated from the first five therapies tested within the exacting approach used by OBTT, four (nicotinamide, erythropoietin, cyclosporine A, and simvastatin) performed below or well below what was expected based on the published literature. OBTT has identified, however, the early post-TBI administration of levetiracetam as a promising agent and has advanced it to a gyrencephalic large animal model--fluid percussion injury in micropigs. The sixth and seventh therapies have just completed testing (glibenclamide and Kollidon VA 64), and an eighth drug (AER 271) is in testing. Incorporation of circulating brain injury biomarker assessments into these pre-clinical studies suggests considerable potential for diagnostic and theranostic utility of glial fibrillary acidic protein in pre-clinical studies. Given the failures in clinical translation of therapies in TBI, rigorous multicenter, pre-clinical approaches to therapeutic screening such as OBTT may be important for the ultimate translation of therapies to the human condition.


Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos/tendências , Fármacos Neuroprotetores/uso terapêutico , Animais , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Masculino , Neurologia/métodos , Neurologia/tendências , Ratos , Ratos Sprague-Dawley
10.
Brain Res ; 1368: 71-81, 2011 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-20951684

RESUMO

One of the histopathological consequences of a penetrating ballistic brain injury is the formation of a permanent cavity. In a previous study using the penetrating ballistic-like brain injury (PBBI) model, engrafted human amnion-derived multipotent progenitor (AMP) cells failed to survive when injected directly in the injury tract, suggesting that the cell survival requires a supportive matrix. In this study, we seated AMP cells in a collagen-based scaffold, injected into the injury core, and investigated cell survival and neuroprotection following PBBI. AMP cells suspended in AMP cell conditioned medium (ACCS) or in a liquefied collagen matrix were injected immediately after a PBBI along the penetrating injury tract. Injured control rats received only liquefied collagen matrix. All animals were allowed to survive two weeks. Consistent with our previous results, AMP cells suspended in ACCS failed to survive; likewise, no collagen was identified at the injury site when injected alone. In contrast, both AMP cells and the collagen were preserved in the injury cavity when injected together. In addition, AMP cells/collagen treatment preserved some apparent brain tissue in the injury cavity, and there was measurable infiltration of endogenous neural progenitor cells and astrocytes into the preserved brain tissue. AMP cells were also found to have migrated into the subventricular zone and the corpus callosum. Moreover, the AMP cell/collagen treatment significantly attenuated the PBBI-induced axonal degeneration in the corpus callosum and ipsilateral thalamus and improved motor impairment on rotarod performance. Overall, collagen-based scaffold provided a supportive matrix for AMP cell survival, migration, and neuroprotection.


Assuntos
Colágeno , Matriz Extracelular/transplante , Traumatismos Cranianos Penetrantes/cirurgia , Células-Tronco Multipotentes/transplante , Degeneração Neural/patologia , Recuperação de Função Fisiológica , Âmnio , Animais , Movimento Celular , Sobrevivência Celular , Corpo Caloso/patologia , Modelos Animais de Doenças , Traumatismos Cranianos Penetrantes/patologia , Traumatismos Cranianos Penetrantes/fisiopatologia , Humanos , Masculino , Microinjeções , Atividade Motora , Degeneração Neural/cirurgia , Ratos , Ratos Sprague-Dawley , Teste de Desempenho do Rota-Rod , Transplante de Células-Tronco , Tálamo/patologia , Alicerces Teciduais , Resultado do Tratamento
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