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1.
Int J Mol Sci ; 22(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361041

RESUMO

Traumatic brain injury (TBI) is a leading cause of disability and mortality worldwide. It can instigate immediate cell death, followed by a time-dependent secondary injury that results from disproportionate microglial and astrocyte activation, excessive inflammation and oxidative stress in brain tissue, culminating in both short- and long-term cognitive dysfunction and behavioral deficits. Within the brain, the hippocampus is particularly vulnerable to a TBI. We studied a new pomalidomide (Pom) analog, namely, 3,6'-dithioPom (DP), and Pom as immunomodulatory imide drugs (IMiD) for mitigating TBI-induced hippocampal neurodegeneration, microgliosis, astrogliosis and behavioral impairments in a controlled cortical impact (CCI) model of TBI in rats. Both agents were administered as a single intravenous dose (0.5 mg/kg) at 5 h post injury so that the efficacies could be compared. Pom and DP significantly reduced the contusion volume evaluated at 24 h and 7 days post injury. Both agents ameliorated short-term memory deficits and anxiety behavior at 7 days after a TBI. The number of degenerating neurons in the CA1 and dentate gyrus (DG) regions of the hippocampus after a TBI was reduced by Pom and DP. DP, but not Pom, significantly attenuated the TBI-induced microgliosis and DP was more efficacious than Pom at attenuating the TBI-induced astrogliosis in CA1 and DG at 7D after a TBI. In summary, a single intravenous injection of Pom or DP, given 5 h post TBI, significantly reduced hippocampal neurodegeneration and prevented cognitive deficits with a concomitant attenuation of the neuroinflammation in the hippocampus.


Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Gliose/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Fatores Imunológicos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Talidomida/análogos & derivados , Animais , Lesões Encefálicas Traumáticas/complicações , Cognição , Gliose/etiologia , Hipocampo/metabolismo , Fatores Imunológicos/farmacologia , Masculino , Memória , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Talidomida/farmacologia , Talidomida/uso terapêutico
2.
Genes (Basel) ; 12(6)2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205689

RESUMO

Accumulation of α-Synuclein (αSyn) in nigral dopaminergic neurons is commonly seen in patients with Parkinson's disease (PD). We recently reported that transduction of intracellular single-chain intrabody targeting the 53-87 amino acid residues of human αSyn by recombinant adeno associated viral vector (AAV-NAC32) downregulated αSyn protein in SH-SY5Y cells and rat brain. This study characterizes the behavioral phenotype and dopaminergic protection in animals receiving AAV-NAC32. Our results show that adult DAT-Cre rats selectively overexpress αSyn in nigra dopaminergic neurons after local administration of AAV-DIO-αSyn. These animals develop PD-like phenotype, including bradykinesia and loss of tyrosine hydroxylase (TH) immunoreactivity in substantia nigra pars compacta dorsal tier (SNcd). An injection of AAV-NAC32 to nigra produces a selective antibody against αSyn and normalizes the behavior. AAV-NAC32 significantly increases TH, while reduces αSyn immunoreactivity in SNcd. Altogether, our data suggest that an AAV-mediated gene transfer of NAC32 antibody effectively antagonizes αSyn-mediated dopaminergic degeneration in nigra, which may be a promising therapeutic candidate for synucleinopathy or PD.


Assuntos
Anticorpos/uso terapêutico , Imunoterapia/métodos , Locomoção , Doença de Parkinson/terapia , alfa-Sinucleína/imunologia , Animais , Anticorpos/imunologia , Células CHO , Cricetinae , Cricetulus , Dependovirus/genética , Neurônios Dopaminérgicos/metabolismo , Vetores Genéticos/genética , Masculino , Doença de Parkinson/genética , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Ratos , Ratos Long-Evans , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , alfa-Sinucleína/química , alfa-Sinucleína/genética
3.
Redox Biol ; 46: 102067, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34315111

RESUMO

Traumatic brain injury (TBI) is a prevalent head injury worldwide which increases the risk of neurodegenerative diseases. Increased reactive oxygen species (ROS) and inflammatory chemokines after TBI induces secondary effects which damage neurons. Targeting NADPH oxidase or increasing redox systems are ways to reduce ROS and damage. Earlier studies show that C-C motif chemokine ligand 5 (CCL5) has neurotrophic functions such as promoting neurite outgrowth as well as reducing apoptosis. Although CCL5 levels in blood are associated with severity in TBI patients, the function of CCL5 after brain injury is unclear. In the current study, we induced mild brain injury in C57BL/6 (wildtype, WT) mice and CCL5 knockout (CCL5-KO) mice using a weight-drop model. Cognitive and memory functions in mice were analyzed by Novel-object-recognition and Barnes Maze tests. The memory performance of both WT and KO mice were impaired after mild injury. Cognition and memory function in WT mice quickly recovered after 7 days but recovery took more than 14 days in CCL5-KO mice. FJC, NeuN and Hypoxyprobe staining revealed large numbers of neurons damaged by oxidative stress in CCL5-KO mice after mTBI. NADPH oxidase activity show increased ROS generation together with reduced glutathione peroxidase-1 (GPX1) and glutathione (GSH) activity in CCL5-KO mice; this was opposite to that seen in WT mice. CCL5 increased GPX1 expression and reduced intracellular ROS levels which subsequently increased cell survival both in primary neuron cultures and in an overexpression model using SHSY5Y cell. Memory impairment in CCL5-KO mice induced by TBI could be rescued by i.p. injection of the GSH precursor - N-acetylcysteine (NAC) or intranasal delivery of recombinant CCL5 into mice after injury. We conclude that CCL5 is an important molecule for GPX1 antioxidant activation during post-injury day 1-3, and protects hippocampal neurons from ROS as well as improves memory function after trauma.

4.
ACS Pharmacol Transl Sci ; 4(2): 858-869, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33860208

RESUMO

GLP-1 agonists have become increasingly interesting as a new Parkinson's disease (PD) clinical treatment strategy. Additional preclinical studies are important to validate this approach and define the disease stage when they are most effective. We hence characterized the efficacy of PT320, a sustained release formulation of the long acting GLP-1 agonist, exenatide, in a progressive PD (MitoPark) mouse model. A clinically translatable biweekly PT320 dose was administered starting at 5 weeks of age and longitudinally evaluated to 24 weeks, and multiple behavioral/cellular parameters were measured. PT320 significantly improved spontaneous locomotor activity and rearing in MitoPark PD mice. "Motivated" behavior also improved, evaluated by accelerating rotarod performance. Behavioral improvement was correlated with enhanced cellular and molecular indices of dopamine (DA) midbrain function. Fast scan cyclic voltammetry demonstrated protection of striatal and nucleus accumbens DA release and reuptake in PT320 treated MitoPark mice. Positron emission tomography showed protection of striatal DA fibers and tyrosine hydroxylase protein expression was augmented by PT320 administration. Early PT320 treatment may hence provide an important neuroprotective therapeutic strategy in PD.

5.
ACS Pharmacol Transl Sci ; 4(2): 980-1000, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33860215

RESUMO

Neuroinflammation contributes to delayed secondary cell death following traumatic brain injury (TBI), has the potential to chronically exacerbate the initial insult, and represents a therapeutic target that has largely failed to translate into human efficacy. Thalidomide-like drugs have effectively mitigated neuroinflammation across cellular and animal models of TBI and neurodegeneration but are complicated by adverse actions in humans. We hence developed N-adamantyl phthalimidine (NAP) as a new thalidomide-like drug to mitigate inflammation without binding to cereblon, a key target associated with the antiproliferative, antiangiogenic, and teratogenic actions seen in this drug class. We utilized a phenotypic drug discovery approach that employed multiple cellular and animal models and ultimately examined immunohistochemical, biochemical, and behavioral measures following controlled cortical impact (CCI) TBI in mice. NAP mitigated LPS-induced inflammation across cellular and rodent models and reduced oligomeric α-synuclein and amyloid-ß mediated inflammation. Following CCI TBI, NAP mitigated neuronal and synaptic loss, neuroinflammation, and behavioral deficits, and is unencumbered by cereblon binding, a key protein underpinning the teratogenic and adverse actions of thalidomide-like drugs in humans. In summary, NAP represents a new class of thalidomide-like drugs with anti-inflammatory actions for promising efficacy in the treatment of TBI and potentially longer-term neurodegenerative disorders.

6.
Front Neurosci ; 15: 635483, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33833663

RESUMO

Traumatic brain injury (TBI) is the most common cause of morbidity among trauma patients; however, an effective pharmacological treatment has not yet been approved. Individuals with TBI are at greater risk of developing neurological illnesses such as Alzheimer's disease (AD) and Parkinson's disease (PD). The approval process for treatments can be accelerated by repurposing known drugs to treat the growing number of patients with TBI. This review focuses on the repurposing of N-acetyl cysteine (NAC), a drug currently approved to treat hepatotoxic overdose of acetaminophen. NAC also has antioxidant and anti-inflammatory properties that may be suitable for use in therapeutic treatments for TBI. Minocycline (MINO), a tetracycline antibiotic, has been shown to be effective in combination with NAC in preventing oligodendrocyte damage. (-)-phenserine (PHEN), an anti-acetylcholinesterase agent with additional non-cholinergic neuroprotective/neurotrophic properties initially developed to treat AD, has demonstrated efficacy in treating TBI. Recent literature indicates that NAC, MINO, and PHEN may serve as worthwhile repositioned therapeutics in treating TBI.

7.
Elife ; 92020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32804078

RESUMO

Traumatic brain injury (TBI) is a serious global health problem, many individuals live with TBI-related neurological dysfunction. A lack of biomarkers of TBI has impeded medication development. To identify new potential biomarkers, we time-dependently evaluated mouse brain tissue and neuronally derived plasma extracellular vesicle proteins in a mild model of TBI with parallels to concussive head injury. Mice (CD-1, 30-40 g) received a sham procedure or 30 g weight-drop and were euthanized 8, 24, 48, 72, 96 hr, 7, 14 and 30 days later. We quantified ipsilateral cortical proteins, many of which differed from sham by 8 hours post-mTBI, particularly GAS-1 and VEGF-B were increased while CXCL16 reduced, 23 proteins changed in 4 or more of the time points. Gene ontology pathways mapped from altered proteins over time related to pathological and physiological processes. Validation of proteins identified in this study may provide utility as treatment response biomarkers.


Assuntos
Biomarcadores/sangue , Concussão Encefálica , Quimiocinas , Citocinas , Animais , Lesões Encefálicas/patologia , Proteínas de Ciclo Celular/análise , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Córtex Cerebral/patologia , Quimiocina CXCL16/análise , Quimiocina CXCL16/genética , Quimiocina CXCL16/metabolismo , Quimiocinas/análise , Quimiocinas/genética , Quimiocinas/metabolismo , Citocinas/análise , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Vesículas Extracelulares/metabolismo , Proteínas Ligadas por GPI/análise , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Ontologia Genética , Redes Reguladoras de Genes , Camundongos , Transcriptoma , Fator B de Crescimento do Endotélio Vascular/análise , Fator B de Crescimento do Endotélio Vascular/genética , Fator B de Crescimento do Endotélio Vascular/metabolismo
8.
Front Neurosci ; 14: 785, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32848559

RESUMO

Background: We previously demonstrated that subcutaneous administration of PT320, a sustained-release (SR) form of exendin-4, resulted in the long-term maintenance of steady-state exenatide (exendin-4) plasma and target levels in 6-hydroxydopamine (6-OHDA)-pretreated animals. Additionally, pre- or post-treatment with PT320 mitigated the early stage of 6-OHDA-induced dopaminergic neurodegeneration. The purpose of this study was to evaluate the effect of PT320 on L-3,4-dihydroxyphenylalanine (L-DOPA)-induced abnormal involuntary movements (AIMs) in the rat 6-OHDA model of Parkinson's disease. Methods: Adult male Sprague-Dawley rats were unilaterally lesioned in the right medial forebrain bundle by 6-OHDA. L-DOPA and benserazide were given daily for 22 days, starting from 4 weeks after lesioning. PT320 was co-administered weekly for 3 weeks. AIM was evaluated on days 1, 16, and 22 after initiating L-DOPA/benserazide + PT320 treatment. Brain tissues were subsequently collected for HPLC measurements of dopamine (DA) and metabolite concentrations. Results: L-DOPA/benserazide increased AIMs of limbs and axial as well as the sum of all dyskinesia scores (ALO) over 3 weeks. PT320 significantly reduced the AIM scores of limbs, orolingual, and ALO. Although PT320 did not alter DA levels in the lesioned striatum, PT320 significantly attenuated 6-OHDA-enhanced DA turnover. Conclusion: PT320 attenuates L-DOPA/benserazide-induced dyskinesia in a 6-OHDA rat model of PD and warrants clinical evaluation to mitigate Parkinson's disease in humans.

9.
Elife ; 92020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32589144

RESUMO

Traumatic brain injury (TBI) causes mortality and disability worldwide. It can initiate acute cell death followed by secondary injury induced by microglial activation, oxidative stress, inflammation and autophagy in brain tissue, resulting in cognitive and behavioral deficits. We evaluated a new pomalidomide (Pom) analog, 3,6'-dithioPom (DP), and Pom as immunomodulatory agents to mitigate TBI-induced cell death, neuroinflammation, astrogliosis and behavioral impairments in rats challenged with controlled cortical impact TBI. Both agents significantly reduced the injury contusion volume and degenerating neuron number evaluated histochemically and by MRI at 24 hr and 7 days, with a therapeutic window of 5 hr post-injury. TBI-induced upregulated markers of microglial activation, astrogliosis and the expression of pro-inflammatory cytokines, iNOS, COX-2, and autophagy-associated proteins were suppressed, leading to an amelioration of behavioral deficits with DP providing greater efficacy. Complementary animal and cellular studies demonstrated DP and Pom mediated reductions in markers of neuroinflammation and α-synuclein-induced toxicity.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Encefalite/tratamento farmacológico , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Talidomida/análogos & derivados , Animais , Citocinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
10.
J Parkinsons Dis ; 10(2): 573-590, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32176654

RESUMO

BACKGROUND: Accumulation of α-synuclein (αSyn) in the dopaminergic neurons is a common pathology seen in patients with Parkinson's disease (PD). Overproduction of αSyn potentiates the formation of oligomeric αSyn aggregates and enhances dopaminergic neuron degeneration. Downregulating intracellular monomeric αSyn prevents the formation of αSyn oligomers and is a potential therapeutic strategy to attenuate the progression of PD. OBJECTIVE: The purpose of this study is to investigate the efficacy of gene delivery of αSyn-specific single-chain antibodies in vitro and in vivo. METHODS AND RESULTS: The plasmids for αSyn and selective antibodies (NAC32, D10, and VH14) were constructed and were transfected to HEK293 and SH-SY5Y cells. Co-expression of αSyn with NAC32, but not D10 or VH14, profoundly downregulated αSyn protein, but not αSyn mRNA levels in these cells. The interaction of αSyn and NAC32 antibody was next examined in vivo. Adeno-associated virus (AAV)-αSyn combined with AAV-NAC32 or AAV-sc6H4 (a negative control virus) were stereotactically injected into the substantia nigra of adult rats. AAV-NAC32 significantly reduced AAV-encoded αSyn levels in the substantia nigra and striatum and increased tyrosine hydroxylase immunoreactivity in the striatum. Also, in the animals injected with AAV-NAC32 alone, endogenous αSyn protein levels were significantly downregulated in the substantia nigra. CONCLUSION: Our data suggest that AAV-mediated gene transfer of NAC32 is a feasible approach for reducing the expression of target αSyn protein in brain.

11.
Exp Neurol ; 324: 113135, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31778663

RESUMO

Traumatic brain injury (TBI) is one of the most common causes of death and disability worldwide. We investigated whether inhibition of p53 using pifithrin (PFT)-α or PFT-µ provides neuroprotective effects via p53 transcriptional dependent or -independent mechanisms, respectively. Sprague Dawley rats were subjected to controlled cortical impact TBI followed by the administration of PFTα or PFT-µ (2 mg/kg, i.v.) at 5 h after TBI. Brain contusion volume, as well as sensory and motor functions were evaluated at 24 h after TBI. TBI-induced impairments were mitigated by both PFT-α and PFT-µ. Fluoro-Jade C staining was used to label degenerating neurons within the TBI-induced cortical contusion region that, together with Annexin V positive neurons, were reduced by PFT-µ. Double immunofluorescence staining similarly demonstrated that PFT-µ significantly increased HO-1 positive neurons and mRNA expression in the cortical contusion region as well as decreased numbers of 4-hydroxynonenal (4HNE)-positive cells. Levels of mRNA encoding for p53, autophagy, mitophagy, anti-oxidant, anti-inflammatory related genes and proteins were measured by RT-qPCR and immunohistochemical staining, respectively. PFT-α, but not PFT-µ, significantly lowered p53 mRNA expression. Both PFT-α and PFT-µ lowered TBI-induced pro-inflammatory cytokines (IL-1ß and IL-6) mRNA levels as well as TBI-induced autophagic marker localization (LC3 and p62). Finally, treatment with PFT-µ mitigated TBI-induced declines in mRNA levels of PINK-1 and SOD2. Our data suggest that both PFT-µ and PFT-α provide neuroprotective actions through regulation of oxidative stress, neuroinflammation, autophagy, and mitophagy mechanisms, and that PFT-µ, in particular, holds promise as a TBI treatment strategy.


Assuntos
Autofagia/efeitos dos fármacos , Benzotiazóis/uso terapêutico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/patologia , Encefalite/tratamento farmacológico , Mitofagia/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Sulfonamidas/uso terapêutico , Tolueno/análogos & derivados , Proteína Supressora de Tumor p53/antagonistas & inibidores , Animais , Antioxidantes/metabolismo , Comportamento Animal , Contusão Encefálica/tratamento farmacológico , Contusão Encefálica/patologia , Contusão Encefálica/psicologia , Lesões Encefálicas Traumáticas/psicologia , Citocinas/metabolismo , Encefalite/patologia , Heme Oxigenase (Desciclizante)/biossíntese , Masculino , Ratos , Ratos Sprague-Dawley , Tolueno/uso terapêutico
12.
CNS Neurosci Ther ; 26(6): 636-649, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31828969

RESUMO

AIM: Traumatic brain injury (TBI) is one of the most common causes of morbidity and mortality of both young adults and the elderly, and is a key contributing factor in about 30% of all injury-associated deaths occurring within the United States of America. Albeit substantial impact has been made to improve our comprehension of the mechanisms that underpin the primary and secondary injury stages initiated by a TBI incident, this knowledge has yet to successfully translate into the development of an effective TBI pharmacological treatment. Developing consent suggests that a TBI can concomitantly trigger multiple TBI-linked cascades that then progress in parallel and, if correct, the multifactorial nature of TBI would make the discovery of a single effective mechanism-targeted drug unlikely. DISCUSSION: We review recent data indicating that the small molecular weight drug (-)-phenserine tartrate (PhenT), originally developed for Alzheimer's disease (AD), effectively inhibits a broad range of mechanisms pertinent to mild (m) and moderate (mod)TBI, which in combination underpin the ensuing cognitive and motor impairments. In cellular and animal models at clinically translatable doses, PhenT mitigated mTBI- and modTBI-induced programmed neuronal cell death (PNCD), oxidative stress, glutamate excitotoxicity, neuroinflammation, and effectively reversed injury-induced gene pathways leading to chronic neurodegeneration. In addition to proving efficacious in well-characterized animal TBI models, significantly mitigating cognitive and motor impairments, the drug also has demonstrated neuroprotective actions against ischemic stroke and the organophosphorus nerve agent and chemical weapon, soman. CONCLUSION: In the light of its tolerability in AD clinical trials, PhenT is an agent that can be fast-tracked for evaluation in not only civilian TBI, but also as a potentially protective agent in battlefield conditions where TBI and chemical weapon exposure are increasingly jointly occurring.

13.
Exp Neurol ; 324: 113113, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31730763

RESUMO

A synthetic monomeric peptide triple receptor agonist, termed "Triagonist" that incorporates glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and glucagon (Gcg) actions, was previously developed to improve upon metabolic and glucose regulatory benefits of single and dual receptor agonists in rodent models of diet-induced obesity and type 2 diabetes. In the current study, the neurotrophic and neuroprotective actions of this Triagonist were probed in cellular and mouse models of mild traumatic brain injury (mTBI), a prevalent cause of neurodegeneration in both the young and elderly. Triagonist dose- and time-dependently elevated cyclic AMP levels in cultured human SH-SY5Y neuronal cells, and induced neurotrophic and neuroprotective actions, mitigating oxidative stress and glutamate excitotoxicity. These actions were inhibited only by the co-administration of antagonists for all three receptor types, indicating the balanced co-involvement of GLP-1, GIP and Gcg receptors. To evaluate physiological relevance, a clinically translatable dose of Triagonist was administered subcutaneously, once daily for 7 days, to mice following a 30 g weight drop close head injury. Triagonist fully mitigated mTBI-induced visual and spatial memory deficits, evaluated at 7 and 30 days post injury. These results establish Triagonist as a novel neurotrophic/protective agent worthy of further evaluation as a TBI treatment strategy.


Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Polipeptídeo Inibidor Gástrico/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Glucagon/agonistas , Fármacos Neuroprotetores/uso terapêutico , Nootrópicos/uso terapêutico , Animais , Lesões Encefálicas Traumáticas/psicologia , Linhagem Celular , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Ácido Glutâmico/toxicidade , Humanos , Injeções Subcutâneas , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fármacos Neuroprotetores/administração & dosagem , Nootrópicos/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Percepção Espacial/efeitos dos fármacos , Percepção Visual/efeitos dos fármacos
14.
Int J Mol Sci ; 20(24)2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31835787

RESUMO

This study analyzed gender differences in the progressive dopamine (DA) deficiency phenotype in the MitoPark (MP) mouse model of Parkinson's disease (PD) with progressive loss of DA release and reuptake in midbrain DA pathways. We found that the progressive loss of these DA presynaptic parameters begins significantly earlier in male than female MP mice. This was correlated with behavioral gender differences of both forced and spontaneous motor behavior. The degeneration of the nigrostriatal DA system in MP mice is earlier and more marked than that of the mesolimbic DA system, with male MP mice again being more strongly affected than female MP mice. After ovariectomy, DA presynaptic and behavioral changes in female mice become very similar to those of male animals. Our results suggest that estrogen, either directly or indirectly, is neuroprotective in the midbrain DA system. Our results are compatible with epidemiological data on incidence and symptom progression in PD, showing that men are more strongly affected than women at early ages.


Assuntos
Dopamina/metabolismo , Atividade Motora , Doença de Parkinson/fisiopatologia , Animais , Comportamento Animal , Modelos Animais de Doenças , Estimulação Elétrica , Feminino , Masculino , Camundongos Endogâmicos C57BL , Ovariectomia , Probabilidade , Tirosina 3-Mono-Oxigenase/metabolismo
15.
Neurobiol Dis ; 130: 104528, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295555

RESUMO

Mild traumatic brain injury (mTBI) is a risk factor for neurodegenerative disorders, such as Alzheimer's disease (AD) and Parkinson's disease (PD). TBI-derived neuropathologies are promoted by inflammatory processes: chronic microgliosis and release of pro-inflammatory cytokines that further promote neuronal dysfunction and loss. Herein, we evaluated the effect on pre-programmed cell death/neuroinflammation/synaptic integrity and function of (-)-Phenserine tartrate (Phen), an agent originally developed for AD. This was studied at two clinically translatable doses (2.5 and 5.0 mg/kg, BID), in a weight drop (concussive) mTBI model in wild type (WT) and AD APP/PSEN1 transgenic mice. Phen mitigated mTBI-induced cognitive impairment, assessed by Novel Object Recognition and Y-maze behavioral paradigms, in WT mice. Phen fully abated mTBI-induced neurodegeneration, evaluated by counting Fluoro-Jade C-positive (FJC+) cells, in hippocampus and cortex of WT mice. In APP/PSEN1 mice, degenerating cell counts were consistently greater across all experimental groups vs. WT mice. mTBI elevated FJC+ cell counts vs. the APP/PSEN1 control (sham) group, and Phen similarly mitigated this. Anti-inflammatory effects on microglial activation (IBA1-immunoreactivity (IR)) and the pro-inflammatory cytokine TNF-α were evaluated. mTBI increased IBA1-IR and TNF-α/IBA1 colocalization vs. sham, both in WT and APP/PSEN1 mice. Phen decreased IBA1-IR throughout hippocampi and cortices of WT mice, and in cortices of AD mice. Phen, likewise, reduced levels of IBA1/TNF-α-IR colocalization volume across all areas in WT animals, with a similar trend in APP/PSEN1 mice. Actions on astrocyte activation by mTBI were followed by evaluating GFAP, and were similarly mitigated by Phen. Synaptic density was evaluated by quantifying PSD-95+ dendritic spines and Synaptophysin (Syn)-IR. Both were significantly reduced in mTBI vs. sham in both WT and APP/PSEN1 mice. Phen fully reversed the PSD-95+ spine loss in WT and Syn-IR decrease in both WT and APP/PSEN1 mice. To associate immunohistochemical changes in synaptic markers with function, hippocampal long term potentiation (LTP) was induced in WT mice. LTP was impaired by mTBI, and this impairment was mitigated by Phen. In synopsis, clinically translatable doses of Phen ameliorated mTBI-mediated pre-programmed cell death/neuroinflammation/synaptic dysfunction in WT mice, consistent with fully mitigating mTBI-induced cognitive impairments. Phen additionally demonstrated positive actions in the more pathologic brain microenvironment of AD mice, further supporting consideration of its repurposing as a treatment for mTBI.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Concussão Encefálica/tratamento farmacológico , Morte Celular/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Fisostigmina/análogos & derivados , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Concussão Encefálica/metabolismo , Concussão Encefálica/patologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Modelos Animais de Doenças , Hipocampo/metabolismo , Hipocampo/patologia , Camundongos , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Fisostigmina/farmacologia , Fisostigmina/uso terapêutico
16.
Cell Transplant ; 28(9-10): 1183-1196, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31177840

RESUMO

Traumatic brain injury (TBI), a major cause of mortality and morbidity, affects 10 million people worldwide, with limited treatment options. We have previously shown that (-)-phenserine (Phen), an acetylcholinesterase inhibitor originally designed and tested in clinical phase III trials for Alzheimer's disease, can reduce neurodegeneration after TBI and reduce cognitive impairments induced by mild TBI. In this study, we used a mouse model of moderate to severe TBI by controlled cortical impact to assess the effects of Phen on post-trauma histochemical and behavioral changes. Animals were treated with Phen (2.5 mg/kg, IP, BID) for 5 days started on the day of injury and the effects were evaluated by behavioral and histological examinations at 1 and 2 weeks after injury. Phen significantly attenuated TBI-induced contusion volume, enlargement of the lateral ventricle, and behavioral impairments in motor asymmetry, sensorimotor functions, motor coordination, and balance functions. The morphology of microglia was shifted to an active from a resting form after TBI, and Phen dramatically reduced the ratio of activated to resting microglia, suggesting that Phen also mitigates neuroinflammation after TBI. While Phen has potent anti-acetylcholinesterase activity, its (+) isomer Posiphen shares many neuroprotective properties but is almost completely devoid of anti-acetylcholinesterase activity. We evaluated Posiphen at a similar dose to Phen and found similar mitigation in lateral ventricular size increase, motor asymmetry, motor coordination, and balance function, suggesting the improvement of these histological and behavioral tests by Phen treatment occur via pathways other than anti-acetylcholinesterase inhibition. However, the reduction of lesion size and improvement of sensorimotor function by Posiphen were much smaller than with equivalent doses of Phen. Taken together, these results show that post-injury treatment with Phen over 5 days significantly ameliorates severity of TBI. These data suggest a potential development of this compound for clinical use in TBI therapy.


Assuntos
Comportamento Animal/efeitos dos fármacos , Contusão Encefálica , Fármacos Neuroprotetores/farmacologia , Fisostigmina/análogos & derivados , Animais , Contusão Encefálica/tratamento farmacológico , Contusão Encefálica/metabolismo , Contusão Encefálica/patologia , Contusão Encefálica/fisiopatologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Inflamação/fisiopatologia , Masculino , Camundongos , Microglia/metabolismo , Microglia/patologia , Fisostigmina/farmacologia , Fatores de Tempo
17.
Brain Res ; 1720: 146301, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31226324

RESUMO

Although a good deal is known about the genetics and pathophysiology of Parkinson's disease (PD), and information is emerging about its cause, there are no pharmacological treatments shown to have a significant, sustained capacity to prevent or attenuate the ongoing neurodegenerative processes. However, there is accumulating clinical results to suggest that physical exercise is such a treatment, and studies of animal models of the dopamine (DA) deficiency associated with the motor symptoms of PD further support this hypothesis. Exercise is a non-pharmacological, economically practical, and sustainable intervention with little or no risk and with significant additional health benefits. In this study, we investigated the long-term effects of voluntary exercise on motor behavior and brain biochemistry in the transgenic MitoPark mouse PD model with progressive degeneration of the DA systems caused by DAT-driven deletion of the mitochondrial transcription factor TFAM in DA neurons. We found that voluntary exercise markedly improved behavioral function, including overall motor activity, narrow beam walking, and rotarod performance. There was also improvement of biochemical markers of nigrostriatal DA input. This was manifested by increased levels of DA measured by HPLC, and of the DA membrane transporter measured by PET. Moreover, exercise increased oxygen consumption and, by inference, ATP production via oxidative phosphorylation. Thus, exercise augmented aerobic mitochondrial oxidative metabolism vs glycolysis in the nigrostriatal system. We conclude that there are clear-cut physiological mechanisms for beneficial effects of exercise in PD.


Assuntos
Doença de Parkinson/metabolismo , Esforço Físico/fisiologia , Animais , Biomarcadores/metabolismo , Corpo Estriado/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Dopamina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/metabolismo , Atividade Motora/fisiologia , Doença de Parkinson/terapia , Substância Negra/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
18.
Eur J Cell Biol ; 98(5-8): 151043, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31138438

RESUMO

Mesencephalic astrocyte-derived neurotrophic factor (MANF) is the only human neurotrophic factor with an evolutionarily-conserved C. elegans homolog, Y54G2A.23 or manf-1. MANF is a small, soluble, endoplasmic-reticulum (ER)-resident protein that is secreted upon ER stress and promotes survival of target cells such as neurons. However, the role of MANF in ER stress and its mechanism of cellular protection are not clear and the function of MANF in C. elegans is only beginning to emerge. In this study, we show that depletion of C. elegans manf-1 causes a slight decrease in lifespan and brood size; furthermore, combined depletion of manf-1 and the IRE-1/XBP-1 ER stress/UPR pathway resulted in sterile animals that did not produce viable progeny. We demonstrate upregulation of markers of ER stress in L1 larval nematodes, as measured by hsp-3 and hsp-4 transcription, upon depletion of manf-1 by RNAi or mutation; however, there was no difference in tunicamycin-induced expression of hsp-3 and hsp-4 between wild-type and MANF-deficient worms. Surprisingly, larval growth arrest observed in wild-type nematodes reared on tunicamycin is completely prevented in the manf-1 (tm3603) mutant. Transcriptional microarray analysis revealed that manf-1 mutant L1 larvae exhibit a novel modulation of innate immunity genes in response to tunicamycin. The hypothesis that manf-1 negatively regulates the innate immunity pathway is supported by our finding that the development of manf-1 mutant larvae compared to wild-type larvae is not inhibited by growth on P. aeruginosa. Together, our data represent the first characterization of C. elegans MANF as a key modulator of organismal ER stress and immunity.


Assuntos
Antibacterianos/farmacologia , Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fatores de Crescimento Neural/deficiência , Fatores de Crescimento Neural/genética , Tunicamicina/farmacologia , Animais , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/microbiologia , Proteínas de Caenorhabditis elegans/metabolismo , Imunidade Inata/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/imunologia , Fatores de Crescimento Neural/metabolismo , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/metabolismo
19.
Cell Transplant ; 28(4): 439-450, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31094216

RESUMO

Stroke is a leading cause of death and severe disability worldwide. After cerebral ischemia, inflammation plays a central role in the development of permanent neurological damage. Reactive oxygen species (ROS) are involved in the mechanism of post-ischemic inflammation. The activation of several inflammatory enzymes produces ROS, which subsequently suppress mitochondrial activity, leading to further tissue damage. Pomalidomide (POM) is a clinically available immunomodulatory and anti-inflammatory agent. Prior cellular studies demonstrate that POM can mitigate oxidative stress and lower levels of pro-inflammatory cytokines, particularly TNF-α, which plays a prominent role in ischemic stroke-induced brain damage and functional deficits. To evaluate the potential value of POM in cerebral ischemia, POM was initially administered to transgenic mice chronically over-expressing TNF-α surfactant protein (SP)-C promoter (SP-C/TNF-α mice) to assess whether systemically administered drug could lower systemic TNF-α level. POM significantly lowered serum levels of TNF-α and IL-5. Pharmacokinetic studies were then undertaken in mice to evaluate brain POM levels following systemic drug administration. POM possessed a brain/plasma concentration ratio of 0.71. Finally, rats were subjected to transient middle cerebral artery occlusion (MCAo) for 60 min, and subsequently treated with POM 30 min thereafter to evaluate action on cerebral ischemia. POM reduced the cerebral infarct volume in MCAo-challenged rats and improved motor activity, as evaluated by the elevated body swing test. POM's neuroprotective actions on ischemic injury represent a potential therapeutic approach for ischemic brain damage and related disorders, and warrant further evaluation.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Talidomida/análogos & derivados , Inibidores da Angiogênese/farmacologia , Animais , Masculino , Camundongos , Ratos , Talidomida/farmacologia , Talidomida/uso terapêutico
20.
J Neurochem ; 150(1): 56-73, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30933310

RESUMO

To determine the role of reduced dopaminergic transmission for declines of forced versus spontaneous behavior, we used a model of Parkinson's disease with progressive degeneration of dopamine (DA) neurons, the MitoPark mouse. Mice were subjected to rotarod tests of motor coordination, and open field and cylinder tests for spontaneous locomotor activity and postural axial support. To measure DA release in dorsal striatum and the shell of Nucleus Accumbens (NAc), we used ex vivo fast-scan cyclic voltammetry in 6- to 24-week-old mice. To determine decline of DA transporter function, we used 18FE-PE2I positron emission tomography. We show here that fast-scan cyclic voltammetry is a sensitive tool to detect evoked DA release dysfunction in MitoPark mice and that electrically evoked DA release is affected earlier in nigrostriatal than mesolimbic DA systems. DA reuptake was also affected more slowly in NAc shell. Positron emission tomography data showed DA uptake to be barely above detection levels in 16- and 20-week-old MitoPark mice. Rotarod performance was not impaired until mice were 16 weeks old, when evoked DA release in striatum had decreased to ≈ 40% of wild-type levels. In contrast, impairment of open field locomotion and rearing began at 10 weeks, in parallel with the initial modest decline of evoked DA release. We conclude that forced behaviors, such as motivation not to fall, can be partially maintained even when DA release is severely compromised, whereas spontaneous behaviors are much more sensitive to impaired DA release, and that presumed secondary non-dopaminergic system alterations do not markedly counteract or aggravate effects of severe impairment of DA release. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.


Assuntos
Comportamento Animal/fisiologia , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Degeneração Neural/metabolismo , Transtornos Parkinsonianos/metabolismo , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Locomoção/fisiologia , Camundongos , Transtornos Parkinsonianos/complicações
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