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1.
Cell ; 185(21): 3913-3930.e19, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36198316

RESUMO

Although women experience significantly higher tau burden and increased risk for Alzheimer's disease (AD) than men, the underlying mechanism for this vulnerability has not been explained. Here, we demonstrate through in vitro and in vivo models, as well as human AD brain tissue, that X-linked ubiquitin specific peptidase 11 (USP11) augments pathological tau aggregation via tau deubiquitination initiated at lysine-281. Removal of ubiquitin provides access for enzymatic tau acetylation at lysines 281 and 274. USP11 escapes complete X-inactivation, and female mice and people both exhibit higher USP11 levels than males. Genetic elimination of usp11 in a tauopathy mouse model preferentially protects females from acetylated tau accumulation, tau pathology, and cognitive impairment. USP11 levels also strongly associate positively with tau pathology in females but not males. Thus, inhibiting USP11-mediated tau deubiquitination may provide an effective therapeutic opportunity to protect women from increased vulnerability to AD and other tauopathies.


Assuntos
Doença de Alzheimer , Tauopatias , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Caracteres Sexuais , Tauopatias/genética , Tauopatias/patologia , Tioléster Hidrolases/genética , Proteases Específicas de Ubiquitina , Proteínas tau/genética
2.
Cell ; 184(10): 2715-2732.e23, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33852912

RESUMO

Traumatic brain injury (TBI) is the largest non-genetic, non-aging related risk factor for Alzheimer's disease (AD). We report here that TBI induces tau acetylation (ac-tau) at sites acetylated also in human AD brain. This is mediated by S-nitrosylated-GAPDH, which simultaneously inactivates Sirtuin1 deacetylase and activates p300/CBP acetyltransferase, increasing neuronal ac-tau. Subsequent tau mislocalization causes neurodegeneration and neurobehavioral impairment, and ac-tau accumulates in the blood. Blocking GAPDH S-nitrosylation, inhibiting p300/CBP, or stimulating Sirtuin1 all protect mice from neurodegeneration, neurobehavioral impairment, and blood and brain accumulation of ac-tau after TBI. Ac-tau is thus a therapeutic target and potential blood biomarker of TBI that may represent pathologic convergence between TBI and AD. Increased ac-tau in human AD brain is further augmented in AD patients with history of TBI, and patients receiving the p300/CBP inhibitors salsalate or diflunisal exhibit decreased incidence of AD and clinically diagnosed TBI.


Assuntos
Doença de Alzheimer/etiologia , Doença de Alzheimer/prevenção & controle , Lesões Encefálicas Traumáticas/complicações , Neuroproteção , Proteínas tau/metabolismo , Acetilação , Doença de Alzheimer/metabolismo , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Biomarcadores/sangue , Biomarcadores/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Linhagem Celular , Diflunisal/uso terapêutico , Feminino , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora) , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Salicilatos/uso terapêutico , Sirtuína 1/metabolismo , Fatores de Transcrição de p300-CBP/antagonistas & inibidores , Fatores de Transcrição de p300-CBP/metabolismo , Proteínas tau/sangue
3.
Cell ; 158(6): 1324-1334, 2014 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-25215490

RESUMO

The P7C3 class of aminopropyl carbazole chemicals fosters the survival of neurons in a variety of rodent models of neurodegeneration or nerve cell injury. To uncover its mechanism of action, an active derivative of P7C3 was modified to contain both a benzophenone for photocrosslinking and an alkyne for CLICK chemistry. This derivative was found to bind nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme involved in the conversion of nicotinamide into nicotinamide adenine dinucleotide (NAD). Administration of active P7C3 chemicals to cells treated with doxorubicin, which induces NAD depletion, led to a rebound in intracellular levels of NAD and concomitant protection from doxorubicin-mediated toxicity. Active P7C3 variants likewise enhanced the activity of the purified NAMPT enzyme, providing further evidence that they act by increasing NAD levels through its NAMPT-mediated salvage.


Assuntos
NAD/metabolismo , Fármacos Neuroprotetores/farmacologia , Animais , Carbazóis/farmacologia , Linhagem Celular Tumoral , Células Cultivadas , Citocinas/agonistas , Citocinas/genética , Citocinas/metabolismo , Doxorrubicina/farmacologia , Humanos , Redes e Vias Metabólicas , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Nicotinamida Fosforribosiltransferase/metabolismo
4.
Proc Natl Acad Sci U S A ; 120(30): e2217128120, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37463212

RESUMO

Oxidative damage in the brain is one of the earliest drivers of pathology in Alzheimer's disease (AD) and related dementias, both preceding and exacerbating clinical symptoms. In response to oxidative stress, nuclear factor erythroid 2-related factor 2 (Nrf2) is normally activated to protect the brain from oxidative damage. However, Nrf2-mediated defense against oxidative stress declines in AD, rendering the brain increasingly vulnerable to oxidative damage. Although this phenomenon has long been recognized, its mechanistic basis has been a mystery. Here, we demonstrate through in vitro and in vivo models, as well as human AD brain tissue, that Slingshot homolog-1 (SSH1) drives this effect by acting as a counterweight to neuroprotective Nrf2 in response to oxidative stress and disease. Specifically, oxidative stress-activated SSH1 suppresses nuclear Nrf2 signaling by sequestering Nrf2 complexes on actin filaments and augmenting Kelch-like ECH-associated protein 1 (Keap1)-Nrf2 interaction, independently of SSH1 phosphatase activity. We also show that Ssh1 elimination in AD models increases Nrf2 activation, which mitigates tau and amyloid-ß accumulation and protects against oxidative injury, neuroinflammation, and neurodegeneration. Furthermore, loss of Ssh1 preserves normal synaptic function and transcriptomic patterns in tauP301S mice. Importantly, we also show that human AD brains exhibit highly elevated interactions of Nrf2 with both SSH1 and Keap1. Thus, we demonstrate here a unique mode of Nrf2 blockade that occurs through SSH1, which drives oxidative damage and ensuing pathogenesis in AD. Strategies to inhibit SSH1-mediated Nrf2 suppression while preserving normal SSH1 catalytic function may provide new neuroprotective therapies for AD and related dementias.


Assuntos
Doença de Alzheimer , Animais , Humanos , Camundongos , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neuroproteção , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/fisiologia
5.
Cell ; 142(1): 39-51, 2010 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-20603013

RESUMO

An in vivo screen was performed in search of chemicals capable of enhancing neuron formation in the hippocampus of adult mice. Eight of 1000 small molecules tested enhanced neuron formation in the subgranular zone of the dentate gyrus. Among these was an aminopropyl carbazole, designated P7C3, endowed with favorable pharmacological properties. In vivo studies gave evidence that P7C3 exerts its proneurogenic activity by protecting newborn neurons from apoptosis. Mice missing the gene encoding neuronal PAS domain protein 3 (NPAS3) are devoid of hippocampal neurogenesis and display malformation and electrophysiological dysfunction of the dentate gyrus. Prolonged administration of P7C3 to npas3(-/-) mice corrected these deficits by normalizing levels of apoptosis of newborn hippocampal neurons. Prolonged administration of P7C3 to aged rats also enhanced neurogenesis in the dentate gyrus, impeded neuron death, and preserved cognitive capacity as a function of terminal aging. PAPERCLIP:


Assuntos
Carbazóis/farmacologia , Avaliação Pré-Clínica de Medicamentos , Neurogênese/efeitos dos fármacos , Neurônios/citologia , Fármacos Neuroprotetores/farmacologia , Envelhecimento/efeitos dos fármacos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carbazóis/química , Cognição/efeitos dos fármacos , Giro Denteado/citologia , Giro Denteado/fisiologia , Feminino , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Fármacos Neuroprotetores/química , Ratos
6.
Genome Res ; 31(10): 1900-1912, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33627474

RESUMO

Because disease-associated microglia (DAM) and disease-associated astrocytes (DAA) are involved in the pathophysiology of Alzheimer's disease (AD), we systematically identified molecular networks between DAM and DAA to uncover novel therapeutic targets for AD. Specifically, we develop a network-based methodology that leverages single-cell/nucleus RNA sequencing data from both transgenic mouse models and AD patient brains, as well as drug-target network, metabolite-enzyme associations, the human protein-protein interactome, and large-scale longitudinal patient data. Through this approach, we find both common and unique gene network regulators between DAM (i.e., PAK1, MAPK14, and CSF1R) and DAA (i.e., NFKB1, FOS, and JUN) that are significantly enriched by neuro-inflammatory pathways and well-known genetic variants (i.e., BIN1). We identify shared immune pathways between DAM and DAA, including Th17 cell differentiation and chemokine signaling. Last, integrative metabolite-enzyme network analyses suggest that fatty acids and amino acids may trigger molecular alterations in DAM and DAA. Combining network-based prediction and retrospective case-control observations with 7.2 million individuals, we identify that usage of fluticasone (an approved glucocorticoid receptor agonist) is significantly associated with a reduced incidence of AD (hazard ratio [HR] = 0.86, 95% confidence interval [CI] 0.83-0.89, P < 1.0 × 10-8). Propensity score-stratified cohort studies reveal that usage of mometasone (a stronger glucocorticoid receptor agonist) is significantly associated with a decreased risk of AD (HR = 0.74, 95% CI 0.68-0.81, P < 1.0 × 10-8) compared to fluticasone after adjusting age, gender, and disease comorbidities. In summary, we present a network-based, multimodal methodology for single-cell/nucleus genomics-informed drug discovery and have identified fluticasone and mometasone as potential treatments in AD.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Animais , Astrócitos/metabolismo , Análise de Dados , Reposicionamento de Medicamentos , Humanos , Camundongos , Microglia/metabolismo , Estudos Retrospectivos , Análise de Sequência de RNA
7.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33836587

RESUMO

The brain requires continuously high energy production to maintain ion gradients and normal function. Mitochondria critically undergird brain energetics, and mitochondrial abnormalities feature prominently in neuropsychiatric disease. However, many unique aspects of brain mitochondria composition and function are poorly understood. Developing improved neuroprotective therapeutics thus requires more comprehensively understanding brain mitochondria, including accurately delineating protein composition and channel-transporter functional networks. However, obtaining pure mitochondria from the brain is especially challenging due to its distinctive lipid and cell structure properties. As a result, conflicting reports on protein localization to brain mitochondria abound. Here we illustrate this problem with the neuropsychiatric disease-associated L-type calcium channel Cav1.2α1 subunit previously observed in crude mitochondria. We applied a dual-process approach to obtain functionally intact versus compositionally pure brain mitochondria. One branch utilizes discontinuous density gradient centrifugation to isolate semipure mitochondria suitable for functional assays but unsuitable for protein localization because of endoplasmic reticulum (ER) contamination. The other branch utilizes self-forming density gradient ultracentrifugation to remove ER and yield ultrapure mitochondria that are suitable for investigating protein localization but functionally compromised. Through this process, we evaluated brain mitochondria protein content and observed the absence of Cav1.2α1 and other previously reported mitochondrial proteins, including the NMDA receptor, ryanodine receptor 1, monocarboxylate transporter 1, excitatory amino acid transporter 1, and glyceraldehyde 3-phosphate dehydrogenase. Conversely, we confirmed mitochondrial localization of several plasma membrane proteins previously reported to also localize to mitochondria. We expect this dual-process isolation procedure will enhance understanding of brain mitochondria in both health and disease.


Assuntos
Encéfalo/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Animais , Cálcio/metabolismo , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Retículo Endoplasmático/metabolismo , Feminino , Homeostase , Humanos , Transporte de Íons , Masculino , Proteínas de Membrana/isolamento & purificação , Camundongos , Camundongos Knockout
8.
PLoS Genet ; 17(4): e1009484, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33886537

RESUMO

Primary cilia are microtubule-based organelles present on most cells that regulate many physiological processes, ranging from maintaining energy homeostasis to renal function. However, the role of these structures in the regulation of behavior remains unknown. To study the role of cilia in behavior, we employ mouse models of the human ciliopathy, Bardet-Biedl Syndrome (BBS). Here, we demonstrate that BBS mice have significant impairments in context fear conditioning, a form of associative learning. Moreover, we show that postnatal deletion of BBS gene function, as well as congenital deletion, specifically in the forebrain, impairs context fear conditioning. Analyses indicated that these behavioral impairments are not the result of impaired hippocampal long-term potentiation. However, our results indicate that these behavioral impairments are the result of impaired hippocampal neurogenesis. Two-week treatment with lithium chloride partially restores the proliferation of hippocampal neurons which leads to a rescue of context fear conditioning. Overall, our results identify a novel role of cilia genes in hippocampal neurogenesis and long-term context fear conditioning.


Assuntos
Síndrome de Bardet-Biedl/genética , Medo/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Neurônios/metabolismo , Animais , Síndrome de Bardet-Biedl/tratamento farmacológico , Síndrome de Bardet-Biedl/patologia , Proliferação de Células/efeitos dos fármacos , Cílios/genética , Cílios/metabolismo , Cílios/patologia , Modelos Animais de Doenças , Medo/fisiologia , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Lítio/farmacologia , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/genética , Transtornos da Memória/patologia , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Neurogênese/genética , Neurônios/patologia
9.
Alzheimers Dement ; 20(2): 1334-1349, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37985399

RESUMO

INTRODUCTION: The molecular mechanisms that contribute to sex differences, in particular female predominance, in Alzheimer's disease (AD) prevalence, symptomology, and pathology, are incompletely understood. METHODS: To address this problem, we investigated cellular metabolism and immune responses ("immunometabolism endophenotype") across AD individuals as a function of sex with diverse clinical diagnosis of cognitive status at death (cogdx), Braak staging, and Consortium to Establish a Registry for AD (CERAD) scores using human cortex metabolomics and transcriptomics data from the Religious Orders Study / Memory and Aging Project (ROSMAP) cohort. RESULTS: We identified sex-specific metabolites, immune and metabolic genes, and pathways associated with the AD diagnosis and progression. We identified female-specific elevation in glycerophosphorylcholine and N-acetylglutamate, which are AD inflammatory metabolites involved in interleukin (IL)-17 signaling, C-type lectin receptor, interferon signaling, and Toll-like receptor pathways. We pinpointed distinct microglia-specific immunometabolism endophenotypes (i.e., lipid- and amino acid-specific IL-10 and IL-17 signaling pathways) between female and male AD subjects. In addition, female AD subjects showed evidence of diminished excitatory neuron and microglia communications via glutamate-mediated immunometabolism. DISCUSSION: Our results point to new understanding of the molecular basis for female predominance in AD, and warrant future independent validations with ethnically diverse patient cohorts to establish a likely causal relationship of microglial immunometabolism in the sex differences in AD. HIGHLIGHTS: Sex-specific immune metabolites, gene networks and pathways, are associated with Alzheimer's disease pathogenesis and disease progression. Female AD subjects exhibit microglial immunometabolism endophenotypes characterized by decreased glutamate metabolism and elevated interleukin-10 pathway activity. Female AD subjects showed a shift in glutamate-mediated cell-cell communications between excitatory neurons to microglia and astrocyte.


Assuntos
Doença de Alzheimer , Humanos , Masculino , Feminino , Doença de Alzheimer/patologia , Microglia/metabolismo , Endofenótipos , Caracteres Sexuais , Glutamatos/genética , Glutamatos/metabolismo
10.
Proc Natl Acad Sci U S A ; 117(44): 27667-27675, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33087571

RESUMO

Chronic neurodegeneration in survivors of traumatic brain injury (TBI) is a major cause of morbidity, with no effective therapies to mitigate this progressive and debilitating form of nerve cell death. Here, we report that pharmacologic restoration of the blood-brain barrier (BBB), 12 mo after murine TBI, is associated with arrested axonal neurodegeneration and cognitive recovery, benefits that persisted for months after treatment cessation. Recovery was achieved by 30 d of once-daily administration of P7C3-A20, a compound that stabilizes cellular energy levels. Four months after P7C3-A20, electron microscopy revealed full repair of TBI-induced breaks in cortical and hippocampal BBB endothelium. Immunohistochemical staining identified additional benefits of P7C3-A20, including restoration of normal BBB endothelium length, increased brain capillary pericyte density, increased expression of BBB tight junction proteins, reduced brain infiltration of immunoglobulin, and attenuated neuroinflammation. These changes were accompanied by cessation of TBI-induced chronic axonal degeneration. Specificity for P7C3-A20 action on the endothelium was confirmed by protection of cultured human brain microvascular endothelial cells from hydrogen peroxide-induced cell death, as well as preservation of BBB integrity in mice after exposure to toxic levels of lipopolysaccharide. P7C3-A20 also protected mice from BBB degradation after acute TBI. Collectively, our results provide insights into the pathophysiologic mechanisms behind chronic neurodegeneration after TBI, along with a putative treatment strategy. Because TBI increases the risks of other forms of neurodegeneration involving BBB deterioration (e.g., Alzheimer's disease, Parkinson's disease, vascular dementia, chronic traumatic encephalopathy), P7C3-A20 may have widespread clinical utility in the setting of neurodegenerative conditions.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Lesões Encefálicas Traumáticas/tratamento farmacológico , Carbazóis/farmacologia , Cognição/efeitos dos fármacos , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Barreira Hematoencefálica/citologia , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/ultraestrutura , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/patologia , Carbazóis/uso terapêutico , Células Cultivadas , Doença Crônica/tratamento farmacológico , Cognição/fisiologia , Modelos Animais de Doenças , Células Endoteliais , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Humanos , Masculino , Camundongos , Microscopia Eletrônica , Microvasos/citologia , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/patologia , Doenças Neurodegenerativas/fisiopatologia , Fármacos Neuroprotetores/uso terapêutico , Cultura Primária de Células , Sobreviventes
11.
Alzheimers Dement ; 19(5): 1876-1887, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36331056

RESUMO

INTRODUCTION: African Americans (AAs) and European Americans (EAs) differ in Alzheimer's disease (AD) prevalence, risk factors, and symptomatic presentation and AAs are less likely to enroll in AD clinical trials. METHODS: We conducted race-conscious pharmacoepidemiologic studies of 5.62 million older individuals (age ≥60) to investigate the association of telmisartan exposure and AD outcome using Cox analysis, Kaplan-Meier analysis, and log-rank test. We performed Mendelian randomization (MR) analysis of large ethnically diverse genetic data to test likely causal relationships between telmisartan's target and AD. RESULTS: We identified that moderate/high telmisartan exposure was significantly associated with a reduced incidence of AD in the AAs compared to low/no telmisartan exposure (hazard ratio [HR] = 0.77, 95% CI: 0.65-0.91, p-value = 0.0022), but not in the non-Hispanic EAs (HR = 0.97, 95% CI: 0.89-1.05, p-value = 0.4110). Sensitivity and sex-/age-stratified patient subgroup analyses identified that telmisartan's medication possession ratio (MPR) and average hypertension daily dosage were significantly associated with a stronger reduction in the incidence of both AD and dementia in AAs. Using MR analysis from large genome-wide association studies (GWAS) (over 2 million individuals) across AD, hypertension, and diabetes, we further identified AA-specific beneficial effects of telmisartan for AD. DISCUSSION: Randomized controlled trials with ethnically diverse patient cohorts are warranted to establish causality and therapeutic outcomes of telmisartan and AD. HIGHLIGHTS: Telmisartan is associated with lower risk of Alzheimer's disease (AD) in African Americans (AAs). Telmisartan is the only angiotensin II receptor blockers having PPAR-γ agonistic properties with beneficial anti-diabetic and renal function effects, which mitigate AD risk in AAs. Mendelian randomization (MR) analysis demonstrates the specificity of telmisartan's protective mechanism to AAs.


Assuntos
Doença de Alzheimer , Diabetes Mellitus , Hipertensão , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/epidemiologia , Negro ou Afro-Americano/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Telmisartan/uso terapêutico , Pessoa de Meia-Idade
12.
Acta Neuropathol ; 144(5): 911-938, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36104602

RESUMO

The mechanistic relationship between amyloid-beta precursor protein (APP) processing and mitochondrial dysfunction in Alzheimer's disease (AD) has long eluded the field. Here, we report that coiled-coil-helix-coiled-coil-helix domain containing 6 (CHCHD6), a core protein of the mammalian mitochondrial contact site and cristae organizing system, mechanistically connects these AD features through a circular feedback loop that lowers CHCHD6 and raises APP processing. In cellular and animal AD models and human AD brains, the APP intracellular domain fragment inhibits CHCHD6 transcription by binding its promoter. CHCHD6 and APP bind and stabilize one another. Reduced CHCHD6 enhances APP accumulation on mitochondria-associated ER membranes and accelerates APP processing, and induces mitochondrial dysfunction and neuronal cholesterol accumulation, promoting amyloid pathology. Compensation for CHCHD6 loss in an AD mouse model reduces AD-associated neuropathology and cognitive impairment. Thus, CHCHD6 connects APP processing and mitochondrial dysfunction in AD. This provides a potential new therapeutic target for patients.


Assuntos
Doença de Alzheimer , Amiloidose , Doença de Alzheimer/patologia , Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Amiloidose/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Mamíferos/metabolismo , Camundongos , Camundongos Transgênicos , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais
13.
Mol Psychiatry ; 26(6): 2286-2298, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32332995

RESUMO

Post-traumatic stress disorder (PTSD) is characterized by persistent fear memory of remote traumatic events, mental re-experiencing of the trauma, long-term cognitive deficits, and PTSD-associated hippocampal dysfunction. Extinction-based therapeutic approaches acutely reduce fear. However, many patients eventually relapse to the original conditioned fear response. Thus, understanding the underlying molecular mechanisms of this condition is critical to developing new treatments for patients. Mutations in the neuropsychiatric risk gene CACNA1C, which encodes the Cav1.2 isoform of the L-type calcium channel, have been implicated in both PTSD and highly comorbid neuropsychiatric conditions, such as anxiety and depression. Here, we report that male mice with global heterozygous loss of cacna1c exhibit exacerbated contextual fear that persists at remote time points (up to 180 days after shock), despite successful acute extinction training, reminiscent of PTSD patients. Because dopamine has been implicated in contextual fear memory, and Cav1.2 is a downstream target of dopamine D1-receptor (D1R) signaling, we next generated mice with specific deletion of cacna1c from D1R-expressing neurons (D1-cacna1cKO mice). Notably, D1-cacna1cKO mice also show the same exaggerated remote contextual fear, as well as persistently elevated anxiety-like behavior and impaired spatial memory at remote time points, reminiscent of chronic anxiety in treatment-resistant PTSD. We also show that D1-cacna1cKO mice exhibit elevated death of young hippocampal neurons, and that treatment with the neuroprotective agent P7C3-A20 eradicates persistent remote fear. Augmenting survival of young hippocampal neurons may thus provide an effective therapeutic approach for promoting durable remission of PTSD, particularly in patients with CACNA1C mutations or other genetic aberrations that impair calcium signaling or disrupt the survival of young hippocampal neurons.


Assuntos
Transtornos de Estresse Pós-Traumáticos , Animais , Canais de Cálcio Tipo L/genética , Condicionamento Clássico , Dopamina , Extinção Psicológica , Medo , Humanos , Masculino , Camundongos , Neurônios , Transtornos de Estresse Pós-Traumáticos/genética
14.
Med Res Rev ; 40(6): 2386-2426, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32656864

RESUMO

Following two decades of more than 400 clinical trials centered on the "one drug, one target, one disease" paradigm, there is still no effective disease-modifying therapy for Alzheimer's disease (AD). The inherent complexity of AD may challenge this reductionist strategy. Recent observations and advances in network medicine further indicate that AD likely shares common underlying mechanisms and intermediate pathophenotypes, or endophenotypes, with other diseases. In this review, we consider AD pathobiology, disease comorbidity, pleiotropy, and therapeutic development, and construct relevant endophenotype networks to guide future therapeutic development. Specifically, we discuss six main endophenotype hypotheses in AD: amyloidosis, tauopathy, neuroinflammation, mitochondrial dysfunction, vascular dysfunction, and lysosomal dysfunction. We further consider how this endophenotype network framework can provide advances in computational and experimental strategies for drug-repurposing and identification of new candidate therapeutic strategies for patients suffering from or at risk for AD. We highlight new opportunities for endophenotype-informed, drug discovery in AD, by exploiting multi-omics data. Integration of genomics, transcriptomics, radiomics, pharmacogenomics, and interactomics (protein-protein interactions) are essential for successful drug discovery. We describe experimental technologies for AD drug discovery including human induced pluripotent stem cells, transgenic mouse/rat models, and population-based retrospective case-control studies that may be integrated with multi-omics in a network medicine methodology. In summary, endophenotype-based network medicine methodologies will promote AD therapeutic development that will optimize the usefulness of available data and support deep phenotyping of the patient heterogeneity for personalized medicine in AD.


Assuntos
Doença de Alzheimer , Células-Tronco Pluripotentes Induzidas , Doença de Alzheimer/tratamento farmacológico , Animais , Reposicionamento de Medicamentos , Endofenótipos , Humanos , Camundongos , Ratos , Estudos Retrospectivos
15.
Stroke ; 51(6): 1855-1861, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32397935

RESUMO

Background and Purpose- We aim to determine the potential impact on stroke thrombolysis of drip-and-ship helicopter flights and specifically of their low-frequency vibrations (LFVs). Methods- Mice with a middle cerebral artery autologous thromboembolic occlusion were randomized to receive rtPA (recombinant tissue-type plasminogen activator; or saline) 90 minutes later in 3 different settings: (1) a motion platform simulator that reproduced the LFV signature of the helicopter, (2) a standardized actual helicopter flight, and (3) a ground control. Results- Mice assigned to the LFV simulation while receiving tPA had smaller infarctions (31.6 versus 54.9 mm3; P=0.007) and increased favorable neurological outcomes (86% versus 28%; P=0.0001) when compared with ground controls. Surprisingly, mice receiving tPA in the helicopter did not exhibit smaller infarctions (47.8 versus 54.9 mm3; P=0.58) nor improved neurological outcomes (37% versus 28%; P=0.71). This could be due to a causative effect of the 20- to 30-Hz band, which was inadvertently attenuated during actual flights. Mice using saline showed no differences between the LFV simulator and controls with respect to infarct size (80.9 versus 95.3; P=0.81) or neurological outcomes (25% versus 11%; P=0.24), ruling out an effect of LFV alone. There were no differences in blood-brain barrier permeability between LFV simulator or helicopter, compared with controls (2.45-3.02 versus 4.82 mm3; P=0.14). Conclusions- Vibration in the low-frequency range (0.5-120 Hz) is synergistic with rtPA, significantly improving the effectiveness of thrombolysis without impairing blood-brain barrier permeability. Our findings reveal LFV as a novel, safe, and simple-to-deliver intervention that could improve the outcomes of patients. Visual Overview- An online visual overview is available for this article.


Assuntos
Infarto Encefálico/terapia , Acidente Vascular Cerebral/terapia , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/farmacologia , Vibração , Animais , Modelos Animais de Doenças , Masculino , Camundongos
16.
Brain Inj ; 32(1): 113-122, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29156991

RESUMO

PRIMARY OBJECTIVE: Repeated traumatic brain injuries (rmTBI) are frequently associated with debilitating neuropsychiatric conditions such as cognitive impairment, mood disorders, and post-traumatic stress disorder. We tested the hypothesis that repeated mild traumatic brain injury impairs spatial memory and enhances anxiety-like behaviour. RESEARCH DESIGN: We used a between groups design using single (smTBI) or repeated (rmTBI) controlled cranial closed skull impacts to mice, compared to a control group. METHODS AND PROCEDURES: We assessed the effects of smTBI and rmTBI using measures of motor performance (Rotarod Test [RT]), anxiety-like behaviour (Elevated Plus Maze [EPM] and Open Field [OF] tests), and spatial memory (Morris Water Maze [MWM]) within 12 days of the final injury. In separate groups of mice, astrocytosis and microglial activation were assessed 24 hours after the final injury using GFAP and IBA-1 immunohistochemistry. MAIN OUTCOMES AND RESULTS: RmTBI impaired spatial memory in the MWM and increased anxiety-like behaviour in the EPM and OFT. In addition, rmTBI elevated GFAP and IBA-1 immunohistochemistry throughout the mouse brain. RmTBI produced astrocytosis and microglial activation, and elicited impaired spatial memory and anxiety-like behaviour. CONCLUSIONS: rmTBI produces acute cognitive and anxiety-like disturbances associated with inflammatory changes in brain regions involved in spatial memory and anxiety.


Assuntos
Ansiedade/etiologia , Comportamento Animal/fisiologia , Concussão Encefálica/complicações , Encefalite/etiologia , Transtornos da Memória/etiologia , Memória Espacial/fisiologia , Animais , Ansiedade/patologia , Ansiedade/psicologia , Astrócitos/patologia , Encéfalo/patologia , Concussão Encefálica/patologia , Concussão Encefálica/psicologia , Encefalite/patologia , Encefalite/psicologia , Gliose/etiologia , Gliose/patologia , Gliose/psicologia , Masculino , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/patologia , Transtornos da Memória/psicologia , Camundongos , Microglia/patologia , Modelos Animais , Atividade Motora/fisiologia , Recidiva
17.
J Stroke Cerebrovasc Dis ; 27(5): 1412-1416, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29398531

RESUMO

BACKGROUND: Exogenous administration of uric acid, a naturally occurring antioxidant that scavenges reactive oxygen species in vasculature, has shown protective efficacy in both rodent models of stroke and human stroke patients in Spain as an adjuvant treatment to mechanical thrombectomy. Before clinical trials can be initiated in the United States, however, confirmation of efficacy in alternative preclinical models is required in accordance with stroke therapy academic industry roundtable-RIGOR criteria. To date, preclinical efficacy has only been established in the acute setting in male rodents. METHODS: To address this need, we subjected 7- to 9-week old ovariectomized female mice to filament-induced right middle cerebral artery ischemia and reperfusion, an established preclinical model of mechanical thrombectomy. Fidelity of the procedure was monitored by laser Doppler flowmetry. A separate lab randomly assigned animals to vehicle versus uric acid infusion, which was initiated immediately after 45 minutes of reperfusion. Poststroke analysis of infarction size and neurologic function were conducted by investigators blind to treatment group, with a 7-day primary endpoint and a 3-day intermediary analysis at 1and. RESULTS: Infarct size and neurologic function at 7 days poststroke were significantly improved in uric acid-treated animals, relative to vehicle. CONCLUSION: Efficacy of uric acid in preclinical models of stroke is now expanded to include female mice analyzed at a later time point than has been investigated previously. These results support stroke therapy academic industry roundtable-RIGOR driven determination of the suitability of acute administration of uric acid as an adjuvant to mechanical thrombectomy in clinical trials for patients with stroke.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Infarto da Artéria Cerebral Média/tratamento farmacológico , Atividade Motora/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Ácido Úrico/farmacologia , Animais , Encéfalo/patologia , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Feminino , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , Camundongos Endogâmicos C57BL , Ovariectomia , Recuperação de Função Fisiológica , Fatores de Tempo
20.
Proc Natl Acad Sci U S A ; 110(26): 10759-64, 2013 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-23754400

RESUMO

Compulsive behavior is a debilitating clinical feature of many forms of neuropsychiatric disease, including Tourette syndrome, obsessive-compulsive spectrum disorders, eating disorders, and autism. Although several studies link striatal dysfunction to compulsivity, the pathophysiology remains poorly understood. Here, we show that both constitutive and induced genetic deletion of the gene encoding the melanocortin 4 receptor (MC4R), as well as pharmacologic inhibition of MC4R signaling, normalize compulsive grooming and striatal electrophysiologic impairments in synapse-associated protein 90/postsynaptic density protein 95-associated protein 3 (SAPAP3)-null mice, a model of human obsessive-compulsive disorder. Unexpectedly, genetic deletion of SAPAP3 restores normal weight and metabolic features of MC4R-null mice, a model of human obesity. Our findings offer insights into the pathophysiology and treatment of both compulsive behavior and eating disorders.


Assuntos
Comportamento Compulsivo/fisiopatologia , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Obesidade/fisiopatologia , Receptor Tipo 4 de Melanocortina/deficiência , Receptor Tipo 4 de Melanocortina/genética , Animais , Peso Corporal , Comportamento Compulsivo/prevenção & controle , Corpo Estriado/fisiopatologia , Modelos Animais de Doenças , Feminino , Asseio Animal/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/antagonistas & inibidores , Obesidade/prevenção & controle , Peptídeos Cíclicos/farmacologia , Receptor Tipo 4 de Melanocortina/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Transmissão Sináptica/fisiologia
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