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1.
Nature ; 599(7886): 650-656, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34732887

RESUMO

Loss of functional mitochondrial complex I (MCI) in the dopaminergic neurons of the substantia nigra is a hallmark of Parkinson's disease1. Yet, whether this change contributes to Parkinson's disease pathogenesis is unclear2. Here we used intersectional genetics to disrupt the function of MCI in mouse dopaminergic neurons. Disruption of MCI induced a Warburg-like shift in metabolism that enabled neuronal survival, but triggered a progressive loss of the dopaminergic phenotype that was first evident in nigrostriatal axons. This axonal deficit was accompanied by motor learning and fine motor deficits, but not by clear levodopa-responsive parkinsonism-which emerged only after the later loss of dopamine release in the substantia nigra. Thus, MCI dysfunction alone is sufficient to cause progressive, human-like parkinsonism in which the loss of nigral dopamine release makes a critical contribution to motor dysfunction, contrary to the current Parkinson's disease paradigm3,4.


Assuntos
Complexo I de Transporte de Elétrons/genética , Complexo I de Transporte de Elétrons/metabolismo , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/patologia , Animais , Axônios/efeitos dos fármacos , Axônios/metabolismo , Axônios/patologia , Morte Celular , Dendritos/metabolismo , Dendritos/patologia , Modelos Animais de Doenças , Progressão da Doença , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Feminino , Levodopa/farmacologia , Levodopa/uso terapêutico , Masculino , Camundongos , Destreza Motora/efeitos dos fármacos , NADH Desidrogenase/deficiência , NADH Desidrogenase/genética , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/fisiopatologia , Fenótipo , Substância Negra/citologia , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo
2.
N Engl J Med ; 388(8): 683-693, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36812432

RESUMO

BACKGROUND: Unilateral focused ultrasound ablation of the internal segment of globus pallidus has reduced motor symptoms of Parkinson's disease in open-label studies. METHODS: We randomly assigned, in a 3:1 ratio, patients with Parkinson's disease and dyskinesias or motor fluctuations and motor impairment in the off-medication state to undergo either focused ultrasound ablation opposite the most symptomatic side of the body or a sham procedure. The primary outcome was a response at 3 months, defined as a decrease of at least 3 points from baseline either in the score on the Movement Disorders Society-Unified Parkinson's Disease Rating Scale, part III (MDS-UPDRS III), for the treated side in the off-medication state or in the score on the Unified Dyskinesia Rating Scale (UDysRS) in the on-medication state. Secondary outcomes included changes from baseline to month 3 in the scores on various parts of the MDS-UPDRS. After the 3-month blinded phase, an open-label phase lasted until 12 months. RESULTS: Of 94 patients, 69 were assigned to undergo ultrasound ablation (active treatment) and 25 to undergo the sham procedure (control); 65 patients and 22 patients, respectively, completed the primary-outcome assessment. In the active-treatment group, 45 patients (69%) had a response, as compared with 7 (32%) in the control group (difference, 37 percentage points; 95% confidence interval, 15 to 60; P = 0.003). Of the patients in the active-treatment group who had a response, 19 met the MDS-UPDRS III criterion only, 8 met the UDysRS criterion only, and 18 met both criteria. Results for secondary outcomes were generally in the same direction as those for the primary outcome. Of the 39 patients in the active-treatment group who had had a response at 3 months and who were assessed at 12 months, 30 continued to have a response. Pallidotomy-related adverse events in the active-treatment group included dysarthria, gait disturbance, loss of taste, visual disturbance, and facial weakness. CONCLUSIONS: Unilateral pallidal ultrasound ablation resulted in a higher percentage of patients who had improved motor function or reduced dyskinesia than a sham procedure over a period of 3 months but was associated with adverse events. Longer and larger trials are required to determine the effect and safety of this technique in persons with Parkinson's disease. (Funded by Insightec; ClinicalTrials.gov number, NCT03319485.).


Assuntos
Globo Pálido , Ablação por Ultrassom Focalizado de Alta Intensidade , Doença de Parkinson , Humanos , Discinesias/etiologia , Discinesias/cirurgia , Globo Pálido/cirurgia , Doença de Parkinson/complicações , Doença de Parkinson/cirurgia , Resultado do Tratamento
3.
Proc Natl Acad Sci U S A ; 119(15): e2113751119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35394873

RESUMO

Although mammalian retinal ganglion cells (RGCs) normally cannot regenerate axons nor survive after optic nerve injury, this failure is partially reversed by inducing sterile inflammation in the eye. Infiltrative myeloid cells express the axogenic protein oncomodulin (Ocm) but additional, as-yet-unidentified, factors are also required. We show here that infiltrative macrophages express stromal cell­derived factor 1 (SDF1, CXCL12), which plays a central role in this regard. Among many growth factors tested in culture, only SDF1 enhances Ocm activity, an effect mediated through intracellular cyclic AMP (cAMP) elevation and phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) activation. SDF1 deficiency in myeloid cells (CXCL12flx/flxLysM-Cre−/+ mice) or deletion of the SDF1 receptor CXCR4 in RGCs (intraocular AAV2-Cre in CXCR4flx/flx mice) or SDF1 antagonist AMD3100 greatly suppresses inflammation-induced regeneration and decreases RGC survival to baseline levels. Conversely, SDF1 induces optic nerve regeneration and RGC survival, and, when combined with Ocm/cAMP, SDF1 increases axon regeneration to levels similar to those induced by intraocular inflammation. In contrast to deletion of phosphatase and tensin homolog (Pten), which promotes regeneration selectively from αRGCs, SDF1 promotes regeneration from non-αRGCs and enables the latter cells to respond robustly to Pten deletion; however, SDF1 surprisingly diminishes the response of αRGCs to Pten deletion. When combined with inflammation and Pten deletion, SDF1 enables many RGCs to regenerate axons the entire length of the optic nerve. Thus, SDF1 complements the effects of Ocm in mediating inflammation-induced regeneration and enables different RGC subtypes to respond to Pten deletion.


Assuntos
Traumatismos do Nervo Óptico , Células Ganglionares da Retina , Axônios/metabolismo , Quimiocina CXCL12/genética , Monócitos/metabolismo , Regeneração Nervosa/fisiologia , Traumatismos do Nervo Óptico/genética , Traumatismos do Nervo Óptico/metabolismo , PTEN Fosfo-Hidrolase/genética , Células Ganglionares da Retina/fisiologia
4.
N Engl J Med ; 382(20): 1926-1932, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32402162

RESUMO

We report the implantation of patient-derived midbrain dopaminergic progenitor cells, differentiated in vitro from autologous induced pluripotent stem cells (iPSCs), in a patient with idiopathic Parkinson's disease. The patient-specific progenitor cells were produced under Good Manufacturing Practice conditions and characterized as having the phenotypic properties of substantia nigra pars compacta neurons; testing in a humanized mouse model (involving peripheral-blood mononuclear cells) indicated an absence of immunogenicity to these cells. The cells were implanted into the putamen (left hemisphere followed by right hemisphere, 6 months apart) of a patient with Parkinson's disease, without the need for immunosuppression. Positron-emission tomography with the use of fluorine-18-L-dihydroxyphenylalanine suggested graft survival. Clinical measures of symptoms of Parkinson's disease after surgery stabilized or improved at 18 to 24 months after implantation. (Funded by the National Institutes of Health and others.).


Assuntos
Neurônios Dopaminérgicos/citologia , Células-Tronco Pluripotentes Induzidas/transplante , Doença de Parkinson/terapia , Parte Compacta da Substância Negra/citologia , Idoso , Animais , Gânglios da Base/diagnóstico por imagem , Gânglios da Base/metabolismo , Diferenciação Celular , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/transplante , Seguimentos , Humanos , Células-Tronco Pluripotentes Induzidas/imunologia , Masculino , Camundongos , Camundongos SCID , Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Putamen/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Transplante Autólogo , Transplante Homólogo
5.
Mol Psychiatry ; 27(5): 2563-2579, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33931727

RESUMO

Heightened aggressive behavior is considered as one of the central symptoms of many neuropsychiatric disorders including autism, schizophrenia, and dementia. The consequences of aggression pose a heavy burden on patients and their families and clinicians. Unfortunately, we have limited treatment options for aggression and lack mechanistic insight into the causes of aggression needed to inform new efforts in drug discovery and development. Levels of proinflammatory cytokines in the periphery or cerebrospinal fluid were previously reported to correlate with aggressive traits in humans. However, it is still unknown whether cytokines affect brain circuits to modulate aggression. Here, we examined the functional role of interleukin 1ß (IL-1ß) in mediating individual differences in aggression using a resident-intruder mouse model. We found that nonaggressive mice exhibit higher levels of IL-1ß in the dorsal raphe nucleus (DRN), the major source of forebrain serotonin (5-HT), compared to aggressive mice. We then examined the effect of pharmacological antagonism and viral-mediated gene knockdown of the receptors for IL-1 within the DRN and found that both treatments consistently increased aggressive behavior of male mice. Aggressive mice also exhibited higher c-Fos expression in 5-HT neurons in the DRN compared to nonaggressive mice. In line with these findings, deletion of IL-1 receptor in the DRN enhanced c-Fos expression in 5-HT neurons during aggressive encounters, suggesting that modulation of 5-HT neuronal activity by IL-1ß signaling in the DRN controls expression of aggressive behavior.


Assuntos
Agressão , Núcleo Dorsal da Rafe , Interleucina-1beta , Serotonina , Agressão/fisiologia , Animais , Núcleo Dorsal da Rafe/metabolismo , Humanos , Individualidade , Interleucina-1beta/metabolismo , Masculino , Camundongos , Serotonina/metabolismo
7.
Proc Natl Acad Sci U S A ; 117(17): 9180-9182, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32284421

RESUMO

The blood-brain barrier (BBB) presents a significant challenge for treating brain disorders. The hippocampus is a key target for novel therapeutics, playing an important role in Alzheimer's disease (AD), epilepsy, and depression. Preclinical studies have shown that magnetic resonance (MR)-guided low-intensity focused ultrasound (FUS) can reversibly open the BBB and facilitate delivery of targeted brain therapeutics. We report initial clinical trial results evaluating the safety, feasibility, and reversibility of BBB opening with FUS treatment of the hippocampus and entorhinal cortex (EC) in patients with early AD. Six subjects tolerated a total of 17 FUS treatments with no adverse events and neither cognitive nor neurological worsening. Post-FUS contrast MRI revealed immediate and sizable hippocampal parenchymal enhancement indicating BBB opening, followed by BBB closure within 24 h. The average opening was 95% of the targeted FUS volume, which corresponds to 29% of the overall hippocampus volume. We demonstrate that FUS can safely, noninvasively, transiently, reproducibly, and focally mediate BBB opening in the hippocampus/EC in humans. This provides a unique translational opportunity to investigate therapeutic delivery in AD and other conditions.


Assuntos
Barreira Hematoencefálica/diagnóstico por imagem , Barreira Hematoencefálica/metabolismo , Terapia por Ultrassom/métodos , Idoso , Doença de Alzheimer/metabolismo , Transporte Biológico , Barreira Hematoencefálica/fisiologia , Encéfalo/fisiologia , Sistemas de Liberação de Medicamentos/métodos , Feminino , Hipocampo/metabolismo , Humanos , Masculino , Microbolhas , Pessoa de Meia-Idade , Ondas Ultrassônicas , Ultrassonografia
8.
Curr Opin Neurol ; 32(4): 566-570, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31232714

RESUMO

PURPOSE OF REVIEW: To summarize the current state of art of gene therapy for Parkinson's disease. RECENT FINDINGS: Introduction of the gene for glutamic acid decarboxylase (GAD) into the subthalamic nucleus was successful in a randomized, double-blind clinical trial and recent data from PET imaging identified novel brain networks underlying both sham surgery and therapeutic responses in treated participants. Two other approaches use viral vectors to increase dopamine transmission in the striatum. Both strategies are being studied in active trials and have recently reported promising responses in human participants. New strategies in Parkinson's disease are focused upon targeting the underlying pathogenesis in those with genetic defects thought to be the cause of disease. Finally, noninvasive focused ultrasound is currently being tested for lesioning in Parkinson's disease patients, but this same technology can be used to transiently open the blood-brain barrier, raising the potential for noninvasive delivery of gene therapy vectors to specific brain targets. SUMMARY: Parkinson's disease gene therapy has moved from purely animal research three decades ago, to initial human studies two decades ago to many applications moving into late stage trials, currently. Recent successes and promising new technology should only accelerate the advance of gene therapy into active clinical practice.


Assuntos
Terapia Genética/métodos , Doença de Parkinson/terapia , Núcleo Subtalâmico/fisiopatologia , Animais , Barreira Hematoencefálica , Corpo Estriado/fisiopatologia , Vetores Genéticos , Humanos , Neuroimagem , Doença de Parkinson/genética , Doença de Parkinson/fisiopatologia , Tomografia por Emissão de Pósitrons , Ultrassonografia de Intervenção
9.
Proc Natl Acad Sci U S A ; 113(3): 734-9, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26733685

RESUMO

Little is known about the molecular similarities and differences between neurons in the ventral (vSt) and dorsal striatum (dSt) and their physiological implications. In the vSt, serotonin [5-Hydroxytryptamine (5-HT)] modulates mood control and pleasure response, whereas in the dSt, 5-HT regulates motor behavior. Here we show that, in mice, 5-HT depolarizes cholinergic interneurons (ChIs) of the dSt whereas hyperpolarizing ChIs from the vSt by acting on different 5-HT receptor isoforms. In the vSt, 5-HT1A (a postsynaptic receptor) and 5-HT1B (a presynaptic receptor) are highly expressed, and synergistically inhibit the excitability of ChIs. The inhibitory modulation by 5-HT1B, but not that by 5-HT1A, is mediated by p11, a protein associated with major depressive disorder. Specific deletion of 5-HT1B from cholinergic neurons results in impaired inhibition of ACh release in the vSt and in anhedonic-like behavior.


Assuntos
Neurônios Colinérgicos/metabolismo , Neostriado/citologia , Serotonina/metabolismo , Acetilcolina/metabolismo , Animais , Comportamento Animal , Deleção de Genes , Interneurônios/citologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Serotonina/metabolismo
10.
Proc Natl Acad Sci U S A ; 113(5): 1429-34, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26787846

RESUMO

The reduced movement repertoire of Parkinson's disease (PD) is mainly due to degeneration of nigrostriatal dopamine neurons. Restoration of dopamine transmission by levodopa (L-DOPA) relieves motor symptoms of PD but often causes disabling dyskinesias. Subchronic L-DOPA increases levels of adaptor protein p11 (S100A10) in dopaminoceptive neurons of the striatum. Using experimental mouse models of Parkinsonism, we report here that global p11 knockout (KO) mice develop fewer jaw tremors in response to tacrine. Following L-DOPA, global p11KO mice show reduced therapeutic responses on rotational motor sensitization, but also develop less dyskinetic side effects. Studies using conditional p11KO mice reveal that distinct cell populations mediate these therapeutic and side effects. Selective deletion of p11 in cholinergic acetyltransferase (ChAT) neurons reduces tacrine-induced tremor. Mice lacking p11 in dopamine D2R-containing neurons have a reduced response to L-DOPA on the therapeutic parameters, but develop dyskinetic side effects. In contrast, mice lacking p11 in dopamine D1R-containing neurons exhibit tremor and rotational responses toward L-DOPA, but develop less dyskinesia. Moreover, coadministration of rapamycin with L-DOPA counteracts L-DOPA-induced dyskinesias in wild-type mice, but not in mice lacking p11 in D1R-containing neurons. 6-OHDA lesioning causes an increase of evoked striatal glutamate release in wild type, but not in global p11KO mice, indicating that altered glutamate neurotransmission could contribute to the reduced L-DOPA responsivity. These data demonstrate that p11 located in ChAT or D2R-containing neurons is involved in regulating therapeutic actions in experimental PD, whereas p11 in D1R-containing neurons underlies the development of L-DOPA-induced dyskinesias.


Assuntos
Anexina A2/fisiologia , Discinesias/fisiopatologia , Levodopa/uso terapêutico , Transtornos Parkinsonianos/tratamento farmacológico , Proteínas S100/fisiologia , Animais , Camundongos , Camundongos Knockout
11.
Proc Natl Acad Sci U S A ; 113(5): 1423-8, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26787858

RESUMO

Complications of dopamine replacement for Parkinson's disease (PD) can limit therapeutic options, leading to interest in identifying novel pathways that can be exploited to improve treatment. p11 (S100A10) is a cellular scaffold protein that binds to and potentiates the activity of various ion channels and neurotransmitter receptors. We have previously reported that p11 can influence ventral striatal function in models of depression and drug addiction, and thus we hypothesized that dorsal striatal p11 might mediate motor function and drug responses in parkinsonian mice. To focally inhibit p11 expression in the dorsal striatum, we injected an adeno-associated virus (AAV) vector producing a short hairpin RNA (AAV.sh.p11). This intervention reduced the impairment in motor function on forced tasks, such as rotarod and treadmill tests, caused by substantia nigra lesioning in mice. Measures of spontaneous movement and gait in an open-field test declined as expected in control lesioned mice, whereas AAV.sh.p11 mice remained at or near normal baseline. Mice with unilateral lesions were then challenged with l-dopa (levodopa) and various dopamine receptor agonists, and resulting rotational behaviors were significantly reduced after ipsilateral inhibition of dorsal striatal p11 expression. Finally, p11 knockdown in the dorsal striatum dramatically reduced l-dopa-induced abnormal involuntary movements compared with control mice. These data indicate that focal inhibition of p11 action in the dorsal striatum could be a promising PD therapeutic target to improve motor function while reducing l-dopa-induced dyskinesias.


Assuntos
Anexina A2/genética , Corpo Estriado/fisiologia , Discinesias/fisiopatologia , Terapia Genética , Atividade Motora , Transtornos Parkinsonianos/fisiopatologia , Proteínas S100/genética , Animais , Camundongos , Camundongos Endogâmicos C57BL , Transtornos Parkinsonianos/terapia
12.
Mov Disord ; 33(5): 843-847, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29701263

RESUMO

BACKGROUND: Magnetic resonance imaging-guided focused ultrasound thalamotomy is approved by the U.S. Food and Drug Administration for treatment of essential tremor. Although this incisionless technology creates an ablative lesion, it potentially avoids serious complications of open stereotactic surgery. OBJECTIVE: To determine the safety profile of magnetic resonance imaging-guided focused ultrasound unilateral thalamotomy for essential tremor, including frequency, and severity of adverse events, including serious adverse events. METHODS: Analysis of safety data for magnetic resonance imaging-guided focused ultrasound thalamotomy (186 patients, five studies). RESULTS: Procedure-related serious adverse events were very infrequent (1.6%), without intracerebral hemorrhages or infections. Adverse events were usually transient and were commonly rated as mild (79%) and rarely severe (1%). As previously reported, abnormalities in sensation and balance were the commonest thalamotomy-related adverse events. CONCLUSION: The overall safety profile of magnetic resonance imaging-guided focused ultrasound thalamotomy supports its role as a new option for patients with medically refractory essential tremor. © 2018 International Parkinson and Movement Disorder Society.


Assuntos
Tremor Essencial , Imageamento por Ressonância Magnética , Doenças do Sistema Nervoso/etiologia , Complicações Pós-Operatórias/etiologia , Tálamo/diagnóstico por imagem , Tálamo/cirurgia , Ultrassonografia de Intervenção , Adulto , Estudos de Coortes , Tremor Essencial/diagnóstico por imagem , Tremor Essencial/cirurgia , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Estados Unidos
13.
J Magn Reson Imaging ; 46(4): 951-971, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28295954

RESUMO

Quantitative susceptibility mapping (QSM) has enabled magnetic resonance imaging (MRI) of tissue magnetic susceptibility to advance from simple qualitative detection of hypointense blooming artifacts to precise quantitative measurement of spatial biodistributions. QSM technology may be regarded to be sufficiently developed and validated to warrant wide dissemination for clinical applications of imaging isotropic susceptibility, which is dominated by metals in tissue, including iron and calcium. These biometals are highly regulated as vital participants in normal cellular biochemistry, and their dysregulations are manifested in a variety of pathologic processes. Therefore, QSM can be used to assess important tissue functions and disease. To facilitate QSM clinical translation, this review aims to organize pertinent information for implementing a robust automated QSM technique in routine MRI practice and to summarize available knowledge on diseases for which QSM can be used to improve patient care. In brief, QSM can be generated with postprocessing whenever gradient echo MRI is performed. QSM can be useful for diseases that involve neurodegeneration, inflammation, hemorrhage, abnormal oxygen consumption, substantial alterations in highly paramagnetic cellular iron, bone mineralization, or pathologic calcification; and for all disorders in which MRI diagnosis or surveillance requires contrast agent injection. Clinicians may consider integrating QSM into their routine imaging practices by including gradient echo sequences in all relevant MRI protocols. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2017;46:951-971.


Assuntos
Artefatos , Meios de Contraste , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Metais , Humanos
14.
Proc Natl Acad Sci U S A ; 111(49): 17636-41, 2014 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-25413364

RESUMO

Recurrent axon collaterals are a major means of communication between spiny projection neurons (SPNs) in the striatum and profoundly affect the function of the basal ganglia. However, little is known about the molecular and cellular mechanisms that underlie this communication. We show that intrastriatal nitric oxide (NO) signaling elevates the expression of the vesicular GABA transporter (VGAT) within recurrent collaterals of SPNs. Down-regulation of striatal NO signaling resulted in an attenuation of GABAergic signaling in SPN local collaterals, down-regulation of VGAT expression in local processes of SPNs, and impaired motor behavior. PKG1 and cAMP response element-binding protein are involved in the signal transduction that transcriptionally regulates VGAT by NO. These data suggest that transcriptional control of the vesicular GABA transporter by NO regulates GABA transmission and action selection.


Assuntos
Gânglios da Base/metabolismo , Guanilato Ciclase/química , Neurônios/metabolismo , Óxido Nítrico/química , Transmissão Sináptica/fisiologia , Ácido gama-Aminobutírico/química , Animais , Axônios/metabolismo , AMP Cíclico/metabolismo , Dopamina/metabolismo , Eletrofisiologia , Retroalimentação Fisiológica , Feminino , Proteínas de Fluorescência Verde/metabolismo , Levodopa/química , Masculino , Camundongos , Plasticidade Neuronal , Oxidopamina/química , Transdução de Sinais , Proteínas Vesiculares de Transporte de Aminoácidos Inibidores/metabolismo
15.
Neurobiol Dis ; 82: 487-494, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26232589

RESUMO

Phosphatase and Tensin homolog deleted on chromosome 10 (PTEN) is a dual lipid-protein phosphatase known primarily as a growth preventing tumor suppressor. PTEN is also expressed in neurons, and pathways modulated by PTEN can influence neuronal function. Here we report a novel function of PTEN as a regulator of striatal dopamine signaling in a model of Parkinson's disease (PD). Blocking PTEN expression with an adeno-associated virus (AAV) vector expressing a small hairpin RNA (shRNA) resulted in reduced responses of cultured striatal neurons to dopamine, which appeared to be largely due to reduction in D2 receptor activation. Co-expression of shRNA-resistant wild-type and mutant forms of PTEN indicated that the lipid-phosphatase activity was essential for this effect. In both normal and Parkinsonian rats, inhibition of striatal PTEN in vivo resulted in motor dysfunction and impaired responses to dopamine, particularly D2 receptor agonists. Expression of PTEN mutants confirmed the lipid-phosphatase activity as critical, while co-expression of a dominant-negative form of Akt overcame the PTEN shRNA effect. These results identify PTEN as a key mediator of striatal responses to dopamine, and suggest that drugs designed to potentiate PTEN expression or activity, such as cancer chemotherapeutics, may also be useful for improving striatal responses to dopamine in conditions of dopamine depletion such as PD. This also suggests that strategies which increase Akt or decrease PTEN expression or function, such as growth factors to prevent neuronal death, may have a paradoxical effect on neurological functioning by inhibiting striatal responses to dopamine.


Assuntos
Corpo Estriado/metabolismo , Dopamina/metabolismo , Atividade Motora/fisiologia , Neurônios/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Transtornos Parkinsonianos/fisiopatologia , Animais , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Células Cultivadas , Corpo Estriado/efeitos dos fármacos , Dependovirus , Agonistas de Dopamina/farmacologia , Vetores Genéticos , Masculino , Atividade Motora/efeitos dos fármacos , Mutação , Neurônios/efeitos dos fármacos , PTEN Fosfo-Hidrolase/genética , Transtornos Parkinsonianos/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno , Ratos Sprague-Dawley , Receptores de Dopamina D2/agonistas , Receptores de Dopamina D2/metabolismo
16.
J Neurooncol ; 121(1): 19-29, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25344882

RESUMO

Malignant gliomas represent one of the most aggressive forms of cancer, displaying high mortality rates and limited treatment options. Specific subpopulations of cells residing in the tumor niche with stem-like characteristics have been postulated to initiate and maintain neoplasticity while resisting conventional therapies. The study presented here aims to define the role of glycogen synthase kinase 3 beta (GSK3b) in patient-derived glioblastoma (GBM) stem-like cell (GSC) proliferation, apoptosis and invasion. To evaluate the potential role of GSK3b in GBM, protein profiles from 68 GBM patients and 20 normal brain samples were analyzed for EGFR-mediated PI3kinase/Akt and GSK3b signaling molecules including protein phosphatase 2A (PP2A). To better understand the function of GSK3b in GBM, GSCs were isolated from GBM patient samples. Blocking GSK3b phosphorylation at Serine 9 attenuated cell proliferation while concomitantly stimulating apoptosis through activation of Caspase-3 in patient-derived GSCs. Increasing GSK3b protein content resulted in the inhibition of cell proliferation, colony formation and stimulated programmed cell death. Depleting GSK3b in GSCs down regulated PP2A. Furthermore, knocking down PP2A or blocking its activity by okadaic acid inactivated GSK3b by increasing GSK3b phosphorylation at Serine 9. Our data suggests that GSK3b may function as a regulator of apoptosis and tumorigenesis in GSCs. Therapeutic approaches targeting GSK3b in glioblastoma stem-like cells may be a useful addition to our current therapeutic armamentarium.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Encéfalo/fisiopatologia , Receptores ErbB/metabolismo , Glioblastoma/fisiopatologia , Quinase 3 da Glicogênio Sintase/metabolismo , Proteína Fosfatase 2/metabolismo , Apoptose/fisiologia , Carcinogênese , Caspase 3/metabolismo , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Glicogênio Sintase Quinase 3 beta , Humanos , Células-Tronco Neoplásicas/fisiologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
17.
Stereotact Funct Neurosurg ; 93(2): 75-93, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25720819

RESUMO

There is increasing interest among functional neurosurgeons in the potential for novel therapies to impact upon diseases beyond movement disorders and pain. A target of increasing interest is the nucleus accumbens (NAc), which has long been studied as a key brain region mediating a variety of behaviors, including reward and satisfaction. As such, focal modulation of the biology of the NAc with deep brain stimulation or novel biological therapies such as gene therapy or cell transplantation could have a major impact upon disorders such as depression and drug addiction. In order to both develop appropriate therapies and then deliver them in an effective fashion, a thorough understanding of the biology, physiology, and anatomy of the NAc is critical. Here, we review the existing literature regarding several areas critical to the development of new therapies, including the known pharmacology, physiology, and connectivity of the NAc, as well as evidence supporting the potential for various NAc surgical therapies in animal models. We then review the relevant anatomy of the NAc, with particular attention to the surgical anatomy, imaging, and targeting necessary to facilitate a proper localization and delivery of new agents to this region. The NAc is a fascinating and potentially rich target for stereotactic neurosurgical intervention, and analysis of existing information regarding all aspects of this structure should help potentiate therapeutic advances and reduce complications from future studies of neurosurgical intervention in this region for a variety of disorders. © 2015 S. Karger AG, Basel.

18.
Proc Natl Acad Sci U S A ; 109(28): 11360-5, 2012 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-22733786

RESUMO

A large number of studies have demonstrated that the nucleus accumbens (NAC) is a critical site in the neuronal circuits controlling reward responses, motivation, and mood, but the neuronal cell type(s) underlying these processes are not yet known. Identification of the neuronal cell types that regulate depression-like states will guide us in understanding the biological basis of mood and its regulation by diseases like major depressive disorder. Taking advantage of recent findings demonstrating that the serotonin receptor chaperone, p11, is an important molecular regulator of depression-like states, here we identify cholinergic interneurons (CINs) as a primary site of action for p11 in the NAC. Depression-like behavior is observed in mice after decrease of p11 levels in NAC CINs. This phenotype is recapitulated by silencing neuronal transmission in these cells, demonstrating that accumbal cholinergic neuronal activity regulates depression-like behaviors and suggesting that accumbal CIN activity is crucial for the regulation of mood and motivation.


Assuntos
Anexina A2/metabolismo , Depressão/fisiopatologia , Interneurônios/metabolismo , Núcleo Accumbens/metabolismo , Proteínas S100/metabolismo , Acetilcolina/metabolismo , Animais , Antidepressivos/farmacologia , Comportamento Animal , Depressão/metabolismo , Imuno-Histoquímica/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , Chaperonas Moleculares/metabolismo , Neurônios/metabolismo , Neurotransmissores/metabolismo , Fenótipo , Receptores Colinérgicos/metabolismo
19.
Med Sci (Paris) ; 31(5): 546-50, 2015 May.
Artigo em Francês | MEDLINE | ID: mdl-26059306

RESUMO

The comorbidity of depression and cocaine addiction suggests shared mechanisms and anatomical pathways. Specifically, the limbic structures, such as the nucleus accumbens (NAc), play a crucial role in both disorders. P11 (S100A10) is a promising target for manipulating depression and addiction in mice. We summarized the recent genetic and viral strategies used to determine how the titration of p11 levels within the NAc affects hedonic behavior and cocaine reward learning in mice. In particular, p11 in the ChAT+ cells or DRD1+ MSN of the NAc, controls depressive-like behavior or cocaine reward, respectively. Treatments to counter maladaptation of p11 levels in the NAc could provide novel therapeutic opportunities for depression and cocaine addiction in humans.


Assuntos
Anexina A2/fisiologia , Depressão/epidemiologia , Transtorno Depressivo/epidemiologia , Proteínas do Tecido Nervoso/fisiologia , Núcleo Accumbens/fisiopatologia , Proteínas S100/fisiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Anedonia/efeitos dos fármacos , Anedonia/fisiologia , Animais , Anexina A2/deficiência , Anexina A2/genética , Comportamento Apetitivo/fisiologia , Neurônios Colinérgicos/efeitos dos fármacos , Neurônios Colinérgicos/fisiologia , Cocaína/farmacologia , Cocaína/toxicidade , Comorbidade , Depressão/fisiopatologia , Depressão/terapia , Transtorno Depressivo/fisiopatologia , Transtorno Depressivo/terapia , Modelos Animais de Doenças , Terapia Genética , Vetores Genéticos/uso terapêutico , Humanos , Interneurônios/efeitos dos fármacos , Interneurônios/fisiologia , Camundongos , Camundongos Knockout , Terapia de Alvo Molecular , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Neurotransmissores/fisiologia , Núcleo Accumbens/efeitos dos fármacos , Optogenética , Prazer/fisiologia , Prevalência , Transporte Proteico/efeitos dos fármacos , Interferência de RNA , Receptores de Neurotransmissores/efeitos dos fármacos , Receptores de Neurotransmissores/metabolismo , Recompensa , Proteínas S100/deficiência , Proteínas S100/genética , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Transtornos Relacionados ao Uso de Substâncias/terapia
20.
J Neurol Neurosurg Psychiatry ; 85(9): 1003-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24444853

RESUMO

BACKGROUND: For patients with psychiatric illnesses remaining refractory to 'standard' therapies, neurosurgical procedures may be considered. Guidelines for safe and ethical conduct of such procedures have previously and independently been proposed by various local and regional expert groups. METHODS: To expand on these earlier documents, representative members of continental and international psychiatric and neurosurgical societies, joined efforts to further elaborate and adopt a pragmatic worldwide set of guidelines. These are intended to address a broad range of neuropsychiatric disorders, brain targets and neurosurgical techniques, taking into account cultural and social heterogeneities of healthcare environments. FINDINGS: The proposed consensus document highlights that, while stereotactic ablative procedures such as cingulotomy and capsulotomy for depression and obsessive-compulsive disorder are considered 'established' in some countries, they still lack level I evidence. Further, it is noted that deep brain stimulation in any brain target hitherto tried, and for any psychiatric or behavioural disorder, still remains at an investigational stage. Researchers are encouraged to design randomised controlled trials, based on scientific and data-driven rationales for disease and brain target selection. Experienced multidisciplinary teams are a mandatory requirement for the safe and ethical conduct of any psychiatric neurosurgery, ensuring documented refractoriness of patients, proper consent procedures that respect patient's capacity and autonomy, multifaceted preoperative as well as postoperative long-term follow-up evaluation, and reporting of effects and side effects for all patients. INTERPRETATION: This consensus document on ethical and scientific conduct of psychiatric surgery worldwide is designed to enhance patient safety.


Assuntos
Encéfalo/cirurgia , Transtornos Mentais/cirurgia , Técnicas Estereotáxicas , Consenso , Humanos , Sociedades Médicas , Técnicas Estereotáxicas/ética , Técnicas Estereotáxicas/normas
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