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1.
Med Biol Eng Comput ; 59(5): 1099-1110, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33881705

RESUMO

There is now a relatively large body of evidence suggesting a relationship between dysfunction of myelin and oligodendrocytes and the etiology of several neuropsychiatric disorders, including depression and schizophrenia, and also suggesting that ultrasound methods may alleviate some of the symptoms of depression. We have applied low-intensity pulsed ultrasound (LIPUS) to the brains of mice treated with the demyelinating drug cuprizone, a drug that has been used as the basis for a rodent model relevant to a number of psychiatric and neurologic disorders including depression, schizophrenia, and multiple sclerosis. Prior to conducting the studies in mice, preliminary studies were carried out on the effects of LIPUS in vitro in neuron-like SH-SY5Y cells and primary glial cells. In subsequent studies in mice, female C57BL/6 mice were restrained in plastic tubes for 20 min daily with the ultrasound transducer near the end of the tube directly above the mouse's head. LIPUS was used at an intensity of 25 mW/cm2 once daily for 22 days in control mice and in mice undergoing daily repetitive restraint stress (RRS). Behavioral or neurochemical studies were done on the mice or the brain tissue obtained from them. The studies in vitro indicated that LIPUS stimulation at an intensity of 15 mW/cm2 delivered for 5 min daily for 3 days in an enclosed sterile cell culture plate in an incubator increased the viability of SH-SY5Y and primary glial cells. In the studies in mice, LIPUS elevated levels of doublecortin, a marker for neurogenesis, in the cortex compared to levels in the RRS mice and caused a trend in elevation of brain levels of brain-derived neurotrophic factor in the hippocampus relative to control levels. LIPUS also increased sucrose preference (a measure of the attenuation of anhedonia, a common symptom of several psychiatric disorders) in the RRS model in mice. The ability of LIPUS administered daily to rescue damaged myelin and oligodendrocytes was studied in mice treated chronically with cuprizone for 35 days. LIPUS increased cortex and corpus callosum levels of myelin basic protein, a protein marker for mature oligodendrocytes, and neural/glial antigen 2, a protein marker for oligodendrocyte precursor cells, relative to levels in the cuprizone + sham animals. These results of this exploratory study suggest that future comprehensive time-related studies with LIPUS on brain chemistry and behavior related to neuropsychiatric disorders are warranted. Exploratory Study on Neurochemical Effects of Low Intensity Pulsed Ultrasound in Brains of Mice. Upper part of figure: LIPUS device and in-vitro cell experimental set-up. The center image is the LIPUS generating box; the image in the upper left shows the cell experiment set-up; the image in the upper right shows a zoomed-in sketch for the cell experiment; the image in the lower left shows the set-up of repetitive restraint stress (RRS) with a mouse; the image in the lower middle shows the set-up of LIPUS treatment of a mouse; the image in the lower right shows a zoomed-in sketch for the LIPUS treatment of a mouse.


Assuntos
Esclerose Múltipla , Ondas Ultrassônicas , Animais , Encéfalo , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Bainha de Mielina
2.
Res Involv Engagem ; 4: 37, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30349739

RESUMO

PLAIN ENGLISH SUMMARY: The Alberta Depression Research Priority Setting Project aimed to meaningfully involve patients, families and clinicians in determining a research agenda aligned to the needs of Albertans who have experienced depression. The project was modeled after a process developed in the UK by the James Lind Alliance and adapted to fit the Alberta, Canada context. This study describes the processes used to ensure the voices of people with lived experience of depression were integrated throughout the project stages. The year long project culminated with a facilitated session to identify the top essential areas of depression research focus. People with lived experience were engaged as part of the project's Steering Committee, as survey participants and as workshop participants. It is hoped this process will guide future priority setting opportunities and advance depression research in Alberta. ABSTRACT: Background The Depression Research Priority Setting (DRPS) project has the clear aim of describing the patient engagement process used to identify depression research priorities and to reflect on the successes of this engagement approach, positive impacts and opportunities for improvement. To help support patient-oriented depression research priority setting in Alberta, the Patient Engagement (PE) Platform of the Alberta Strategy for Patient Oriented Research Support for People and Patient-Oriented Research and Trials (SUPPORT) Unit designed, along with the support of their partners in addictions and mental health, an explit process to engage patients in the design and execution of the DRPS. Methods The UK's James Lind Alliance (JLA) Priority Setting Partnership (PSP) method was adapted into a six step process to ensure voices of "people with lived experience" (PWLE) with depression were included throughout the project stages. This study uses an explicit and parallel patient engagement process throughout each estage of the PSP designed by the PE Platform. Patient engagement was divided into a five step process: i) Awareness and relationship building; ii) Co-designing and co-developing a shared decision making process; iii) Collaborative communication; iv) Collective sensemaking; and v) Acknowledgement, celebration and recognition. A formative evaluation of the six PE processes was undertaken to explore the success of the parallel patient engagement process. Results This project was successful in engaging people with lived depression experience as partners in research priority setting, incorporating their voices into the discussions and decisions that led to the top 25 depression research questions. Conclusions The DRPS project has positively contributed to depression research in Canada by identifying the priorities of Albertans who have experienced depression for depression research. Dissemination activities to promote further knowledge exchange of prioritized research questions, with emphasis on the importance of process in engaging the voices of PWLE of depression are planned.

3.
CMAJ Open ; 6(3): E398-E405, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30266777

RESUMO

BACKGROUND: To support patient-oriented setting of priorities for depression research in Alberta, the Patient Engagement Platform of the Alberta Strategy for Patient Oriented Research's Support for People and Patient-Oriented Research and Trials Unit and Alberta Health Services' Addiction and Mental Health Strategic Clinical Network, along with partners in addictions and mental health, designed the Alberta Depression Research Priority Setting Project. The aim of the project was to survey patients, caregivers and clinicians/researchers in Alberta about what they considered to be the most important unanswered questions about depression. METHODS: The project adapted the James Lind Alliance Priority Setting Partnership method into a 6-step process to gather and prioritize questions about depression posed by people with lived depression experience, which included patients, caregivers, clinicians and health care practitioners. RESULTS: Implementation of the project, from initial data collection to final priority setting, took 10 months (August 2016 to June 2017). A total of 445 Albertans with lived experience of depression participated, ultimately identifying 11 priority depression research questions spanning the health continuum, life stages, and treatment and prevention opportunities. INTERPRETATION: This project is a fundamental step that has the potential to positively influence depression research. Including the voices of Albertans with lived experience will create advantages for depression research for Albertans, researchers and research funders, and for patient engagement in the research enterprise overall.

4.
Chin J Integr Med ; 2016 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-27081000

RESUMO

OBJECTIVE: To investigate if Areca catechu L. treatment could ameliorate depressive symptoms and cognitive decline by facilitating myelination processes in prefrontal cortex. METHODS: A mouse model of cuprizoneinduced demyelination was used to mimic demyelinating disease. Two concentrations of A. catechu nut extract (ANE; 1% and 2%) were administered orally in the diet for 8 weeks. Depressive symptoms and cognition-associated behaviors were evaluated in tests of locomotor activity, tail suspension, and forced swimming; spatial memory was tested with the Y-maze. Expression of myelin basic protein (MBP), 2',3'-cyclic-nucleotide 3'-phosphodiesterase (CNPase), glutathione S-transferases pi (GSTpi), brain-derived neurotrophic factor (BDNF), and the transcription factor cyclic adenosine monophosphate (cAMP) response element-binding (CREB) were evaluated by western blot. RESULTS: Animals subjected to demyelination showed hyperactivity (P<0.01), impaired spatial memory (P<0.01), and depressive behaviors (P<0.05). Internally, they displayed signifificant myelin damage in the cortex, lower expression of CNPase and GSTpi, slightly decreased BDNF (P>0.05), and signifificantly reduced p-CREB (P<0.05). Nevertheless, ANE treatment demonstrated signifificant anti-depressant activity and enhancement of working memory (P<0.05 or 0.01). In addition, ANE treatment increased MBP, CNPase and GSTpi protein expression in prefrontal cortex (P<0.05). Concomitant with increased BDNF production (P<0.05), ANE treatment up-regulated phosphorylated CREB, but without statistical signifificance (P>0.05). CONCLUSION: ANE treatment might ameliorate depressive symptoms and cognitive decline by facilitating myelination processes in prefrontal cortex via induction of BDNF-CREB activation.

5.
Artigo em Inglês | MEDLINE | ID: mdl-25815032

RESUMO

Schizophrenia is a serious psychiatric illness with an unclear cause. One theory is that demyelination of white matter is one of the main pathological factors involved in the development of schizophrenia. The current study evaluated the protective effects of Areca catechu nut extract (ANE) on a cuprizone-induced demyelination mouse model. Two doses of ANE (1% and 2%) were administered orally in the diet for 8 weeks. Animals subjected to demyelination showed impaired spatial memory and less social activity. In addition, mice subjected to demyelination displayed significant myelin damage in cortex and demonstrated a higher expression of NG2 and PDGFRα and AMPK activation. ANE treatment not only significantly enhanced cognitive ability and social activity, but also protected myelin against cuprizone toxicity by promoting oligodendrocyte precursor cell (OPC) differentiation. In addition, ANE treatment demonstrated significant dephosphorylation of AMPKα, indicating a regulatory role for ANE in schizophrenia. This study showed that ANE treatment may enhance cognitive ability and social activity by facilitating OPC differentiation and protecting against myelin damage in cortex. Results also suggest the AMPK signaling pathway may be involved in this process.

6.
J Neurochem ; 131(2): 229-38, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24934403

RESUMO

Serotonin/norepinephrine reuptake inhibitors antidepressants exert their effects by increasing serotonin and norepinephrine in the synaptic cleft. Studies show it takes 2-3 weeks for the mood-enhancing effects, which indicate other mechanisms may underlie their treatment effects. Here, we investigated the role of white matter in treatment and pathogenesis of depression using an unpredictable chronic mild stress (UCMS) mouse model. Desvenlafaxine (DVS) was orally administrated to UCMS mice at the dose of 10 mg/kg/day 1 week before they went through a 7-week stress procedure and lasted for over 8 weeks before the mice were killed. No significant changes were found for protein markers of neurons and astrocytes in UCMS mice. However, myelin and oligodendrocyte-related proteins were significantly reduced in UCMS mice. DVS prevented the stress-induced injury to white matter and the decrease of phosphorylated 5'-AMP-activated protein kinase and 3-hydroxy-3-methyl-glutaryl-CoA reductase protein expression. DVS increased open arm entries in an elevated plus-maze test, sucrose consumption in the sucrose preference test and decreased immobility in tail suspension and forced swimming tests. These findings suggest that stress induces depression-like behaviors and white matter deficits in UCMS mice. DVS may ameliorate the oligodendrocyte dysfunction by affecting cholesterol synthesis, alleviating the depression-like phenotypes in these mice. We examined the possible role of oligodendrocyte and myelin in the pathological changes of depression with an unpredictable chronic mild stress (UCMS) mouse model. Oligodendrocyte-related proteins in the mouse brain were specifically changed during the stress period. The depressive-like behaviors and oligodendrocyte deficits could be prevented by the administration of desvenlafaxine. Oligodendrocyte and myelin may be an essential target of desvenlafaxine for the treatment of depression.


Assuntos
Colesterol/biossíntese , Cicloexanóis/uso terapêutico , Depressão/tratamento farmacológico , Depressão/enzimologia , Modelos Animais de Doenças , Substância Branca/enzimologia , Animais , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Cicloexanóis/farmacologia , Depressão/patologia , Succinato de Desvenlafaxina , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Distribuição Aleatória , Substância Branca/efeitos dos fármacos , Substância Branca/patologia
7.
J Neurochem ; 130(6): 780-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24862291

RESUMO

Previous studies have demonstrated that quetiapine (QTP) may have neuroprotective properties; however, the underlying mechanisms have not been fully elucidated. In this study, we identified a novel mechanism by which QTP increased the synthesis of ATP in astrocytes and protected GABAergic neurons from aging-induced death. In 12-month-old mice, QTP significantly improved cell number of GABAegic neurons in the cortex and ameliorated anxiety-like behaviors compared to control group. Complimentary in vitro studies showed that QTP had no direct effect on the survival of aging GABAergic neurons in culture. Astrocyte-conditioned medium (ACM) pretreated with QTP (ACMQTP) for 24 h effectively protected GABAergic neurons against aging-induced spontaneous cell death. It was also found that QTP boosted the synthesis of ATP from cultured astrocytes after 24 h of treatment, which might be responsible for the protective effects on neurons. Consistent with the above findings, a Rhodamine 123 test showed that ACMQTP, not QTP itself, was able to prevent the decrease in mitochondrial membrane potential in the aging neurons. For the first time, our study has provided evidence that astrocytes may be the conduit through which QTP is able to exert its neuroprotective effects on GABAergic neurons. The neuroprotective properties of quetiapine (QTP) have not been fully understood. Here, we identify a novel mechanism by which QTP increases the synthesis of ATP in astrocytes and protects GABAergic neurons from aging-induced death in a primary cell culture model. In 12-month-old mice, QTP significantly improves cell number of GABAegic neurons and ameliorates anxiety-like behaviors. Our study indicates that astrocytes may be the conduit through which QTP exerts its neuroprotective effects on GABAergic neurons.


Assuntos
Envelhecimento/psicologia , Antipsicóticos/farmacologia , Ansiedade/psicologia , Astrócitos/fisiologia , Comportamento Animal/efeitos dos fármacos , Dibenzotiazepinas/farmacologia , Neurônios/efeitos dos fármacos , Substâncias Protetoras , Ácido gama-Aminobutírico/fisiologia , Trifosfato de Adenosina/biossíntese , Trifosfato de Adenosina/metabolismo , Animais , Contagem de Células , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultivo Condicionados , Escuridão , Comportamento Exploratório/efeitos dos fármacos , Feminino , Imuno-Histoquímica , Luz , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Cultura Primária de Células , Fumarato de Quetiapina , Regulação para Cima/efeitos dos fármacos
8.
Psychiatry Res ; 216(3): 438-45, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24613202

RESUMO

Cuprizone (CPZ) induced demyelinating mouse has been used as an animal model to examine the assumed roles of altered oligodendrocytes in the pathophysiology and treatment of schizophrenia. The objectives of this study were to examine the effect of olanzapine, an atypical antipsychotic, on cuprizone-induced neuropathological changes in the frontal cortex of C57BL/6 mice, and to explore the underlying mechanism for the possible protective effects. The effects of six-week olanzapine (10 mg/kg/day) treatments on neuropathological changes were examined by immunohistochemistry and Western-blot analyses. Olanzapine treatment for six weeks effectively decreased the breakdown of myelin and oligodendrocytes loss of cuprizone-fed mice. Reactive cellular changes, including astrocyte gliosis, microglia accumulation and increased activation of oligodendrocyte progenitor cells, were also attenuated by olanzapine. However, the cortical expression level of insulin-like growth factor 1 (IGF-1) was significantly increased by olanzapine treatment in cuprizone-fed mice as measured by the quantitative real-time polymerase chain reaction (PCR) method. Olanzapine treatment in control mice consuming normal food had no effect on all above measures. These results provide the first in vivo evidence for the protective effects of olanzapine on cuprizone-induced neuropathological changes and suggest that up-regulated insulin-like growth factor 1 may contribute to the protective effects of this antipsychotic.


Assuntos
Antipsicóticos/farmacologia , Benzodiazepinas/farmacologia , Cuprizona/toxicidade , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/patologia , Fator de Crescimento Insulin-Like I/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/patologia , Doenças Desmielinizantes/prevenção & controle , Feminino , Lobo Frontal/citologia , Fator de Crescimento Insulin-Like I/genética , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Bainha de Mielina/metabolismo , Olanzapina , Oligodendroglia/citologia , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Esquizofrenia/tratamento farmacológico , Esquizofrenia/patologia , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos
9.
Synapse ; 64(8): 602-10, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20340167

RESUMO

Cognitive and motor deficits are pervasive in children that suffer early brain injury. The aim of this study was to determine the impact that early damage has on dendritic spine density and other aspects of dendritic morphology of neurons in the motor cortex. Also of interest was how changes in dendritic structure evolved across the lifespan. Ischemia was induced in 10-day-old Long Evans rats by injection of Rose Bengal dye and a laser positioned over right motor cortex. Animals were sacrificed at two and six months of age, and brains were processed for Golgi-Cox staining. Animals exposed to early damage exhibited increases in length of basilar dendrites at two months of age, however no differences in spine density were found across groups at this age. At six months of age, injured animals demonstrated an overall decrease in apical and basilar spine density. Our results suggest that the changes in dendritic length and spine density observed after early damage are unable to be maintained as the animal ages. The observation that increases in spine density do not necessarily coincide with increases in dendritic length suggests that the two processes may not be dependent on one another and suggest two independent plasticity processes responding to damage.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Dano Encefálico Crônico/patologia , Dendritos/patologia , Espinhas Dendríticas/patologia , Córtex Motor/crescimento & desenvolvimento , Córtex Motor/patologia , Acidente Vascular Cerebral/patologia , Animais , Dano Encefálico Crônico/etiologia , Dano Encefálico Crônico/fisiopatologia , Modelos Animais de Doenças , Masculino , Córtex Motor/fisiopatologia , Ratos , Ratos Long-Evans , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia
10.
Dev Psychobiol ; 50(7): 633-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18985861

RESUMO

Autism occurs in 1 in 1,000 children and incidence may be increasing. Investigating brain development and developmental injury in humans is difficult. As such, many studies rely on animal models of disorders. We chose to investigate the valproic acid-exposed rat, as this model shares many similarities with autism. Pregnant Long-Evans rats were administered either valproic acid (VPA) or saline during fetal neural tube development. Morphological analyses of cells in layer II of the golgi impregnated motor cortex were done to determine dendritic length, volume, and complexity in both groups. No differences were found in length or volume of cortical dendrites, but dendritic arborization was more complex in apical dendrites of pyramidal cells in VPA-exposed animals than controls. The implication of this finding is that pruning in the VPA-exposed rat is not occurring, which is consistent with theories related to abnormal human brain development in autism.


Assuntos
Transtorno Autístico/patologia , Modelos Animais de Doenças , Córtex Motor/patologia , Neurônios/patologia , Fatores Etários , Animais , Transtorno Autístico/induzido quimicamente , Dendritos/efeitos dos fármacos , Dendritos/patologia , Feminino , Masculino , Córtex Motor/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Gravidez , Células Piramidais/efeitos dos fármacos , Células Piramidais/patologia , Ratos , Ratos Long-Evans , Ácido Valproico
11.
Behav Neurosci ; 121(6): 1415-20, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18085895

RESUMO

Proinflammatory cytokines have been shown to disrupt the normal transfer of short-term memory to long-term storage sites. Previous research has focused predominantly on the effect of cytokines on hippocampus-mediated spatial learning. To further understand the effects of cytokines on learning and memory, the authors evaluated the effects of interleukin-1beta (IL-1beta) on a motor learning task. Male Long-Evans rats were rewarded with food pellets after they traversed a runway. The runway was either flat (control condition) or had up-ended dowels (motor learning condition). Subjects traversed the flat runway or dowel task for 5 days, 10 trials per day, and were treated with either saline or with 4 microg/kg IL-1beta immediately after training on the first 2 days. Rats in the motor learning task treated with IL-1beta were consistently slower at traversing the runway. IL-1beta did not impair performance in the control condition; rats in the flat condition performed similarly regardless of whether they were treated with saline or IL-1beta. These data are the first evidence demonstrating IL-1beta can disrupt performance in a motor learning task.


Assuntos
Interleucina-1beta/efeitos adversos , Deficiências da Aprendizagem/induzido quimicamente , Destreza Motora/efeitos dos fármacos , Análise de Variância , Animais , Comportamento Animal/efeitos dos fármacos , Deficiências da Aprendizagem/fisiopatologia , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Long-Evans , Reforço Psicológico , Fatores de Tempo
12.
Neurobiol Learn Mem ; 87(3): 404-15, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17141532

RESUMO

Learning a new motor skill can induce neuronal plasticity in rats. Within motor cortex, learning-induced plasticity includes dendritic reorganization, synaptogenesis, and changes in synapse morphology. Behavioral studies have demonstrated that learning requires protein synthesis. It is likely that some of the proteins synthesized during learning are involved in, or the result of, learning-induced structural plasticity. We predicted the expression of proteins involved in neural plasticity would be altered in a learning dependent fashion. Long-Evans rats were trained on a series of motor tasks that varied in complexity, so that the effects of activity could be teased apart from the effects of learning. The motor cortices were examined for MAP2 and synaptophysin protein using Western blotting and immunohistochemistry. Western blotting revealed that expression of MAP2 was not detectably influenced by learning, whereas synaptophysin expression increased on day 1, 3, and 5 of complex motor skill learning. Expression of MAP2 does not seem to indicate difficulty of task or duration of training time, whereas increases in synaptophysin expression, which appear diffusely across the cortex, seem to be correlated with the first 5 days of motor skill learning. Similar findings with GAP-43 suggest the change in synaptophysin may coincide with synapse formation. Immunohistochemistry did not reveal any localized changes in protein expression. These data indicate a difference in learning-induced expression in the mammalian brain compared to reports in the literature, which have often focused on stimulation to induce alterations in protein expression.


Assuntos
Córtex Cerebral/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Destreza Motora/fisiologia , Sinapses/metabolismo , Sinaptofisina/metabolismo , Adaptação Fisiológica , Animais , Western Blotting , Feminino , Proteína GAP-43/metabolismo , Imuno-Histoquímica , Aprendizagem/fisiologia , Córtex Motor/metabolismo , Plasticidade Neuronal/fisiologia , Ratos , Ratos Long-Evans
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