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1.
Sheng Li Xue Bao ; 73(3): 471-481, 2021 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-34230948

RESUMO

Sleep exerts important functions in the regulation of cognition and emotion. Recent studies have found that sleep disorder is one of the important risk factors for Alzheimer's disease (AD), but the effects of chronic sleep deprivation on the cognitive functions of AD model mice and its possible mechanism are still unclear. In the present study, 8-month-old male APP/PS1/tau triple transgenic AD model (3xTg-AD) mice and wild type (WT) mice (n = 8 for each group) were subjected to chronic sleep deprivation by using the modified multiple platform method, with 20 h of sleep deprivation each day for 21 days. Then, open field test, elevated plus maze test, sugar water preference test, object recognition test, Y maze test and conditioned fear memory test were performed to evaluate anxiety- and depression-like behaviors, and multiple cognitive functions. In addition, the immunohistochemistry technique was used to observe pathological characteristics in the hippocampus of mice. The results showed that: (1) Chronic sleep deprivation did not affect anxiety- (P = 0.539) and depression-like behaviors (P = 0.874) in 3xTg-AD mice; (2) Chronic sleep deprivation exacerbated the impairments of object recognition memory (P < 0.001), working memory (P = 0.002) and the conditioned fear memory (P = 0.039) in 3xTg-AD mice; (3) Chronic sleep deprivation increased amyloid ß (Aß) deposition (P < 0.001) and microglial activation (P < 0.001) in the hippocampus of 3xTg-AD mice, without inducing abnormal tau phosphorylation and neurofibrillary tangles. These results indicate that chronic sleep deprivation exacerbates the impairments of recognition memory, working memory and conditioned fear memory in 3xTg-AD mice by aggravating Aß deposition and the excessive activation of microglia in the hippocampus.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Precursor de Proteína beta-Amiloide/genética , Animais , Cognição , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Presenilina-1 , Privação do Sono , Proteínas tau
2.
Nat Commun ; 12(1): 4048, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193869

RESUMO

The ongoing SARS-CoV-2 pandemic necessitates the fast development of vaccines. Recently, viral mutants termed variants of concern (VOC) which may escape host immunity have emerged. The efficacy of spike encoding mRNA vaccines (CVnCoV and CV2CoV) against the ancestral strain and the VOC B.1.351 was tested in a K18-hACE2 transgenic mouse model. Naive mice and mice immunized with a formalin-inactivated SARS-CoV-2 preparation were used as controls. mRNA-immunized mice develop elevated SARS-CoV-2 RBD-specific antibody and neutralization titers which are readily detectable, but significantly reduced against VOC B.1.351. The mRNA vaccines fully protect from disease and mortality caused by either viral strain. SARS-CoV-2 remains undetected in swabs, lung, or brain in these groups. Despite lower neutralizing antibody titers compared to the ancestral strain BavPat1, CVnCoV and CV2CoV show complete disease protection against the novel VOC B.1.351 in our studies.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/imunologia , Animais , Linhagem Celular , Chlorocebus aethiops , Genoma Viral/genética , Humanos , Camundongos , Camundongos Transgênicos , SARS-CoV-2/genética , Células Vero
3.
Int J Mol Sci ; 22(12)2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34203049

RESUMO

The present study aims to determine the neuroprotective effect of Bergenin against spatial memory deficit associated with neurodegeneration. Preliminarily, the protective effect of Bergenin was observed against H2O2-induced oxidative stress in HT-22 and PC-12 cells. Further studies were performed in 5xFAD Tg mouse model by administering Bergenin (1, 30 and 60 mg/kg; orally), whereas Bergenin (60 mg/kg) significantly attenuated the memory deficit observed in the Y-maze and Morris water maze (MWM) test. Fourier transform-infrared (FT-IR) spectroscopy displayed restoration of lipids, proteins and their derivatives compared to the 5xFAD Tg mice group. The differential scanning calorimeter (DSC) suggested an absence of amyloid beta (Aß) aggregation in Bergenin-treated mice. The immunohistochemistry (IHC) analysis suggested the neuroprotective effect of Bergenin by increasing Reelin signaling (Reelin/Dab-1) and attenuated Aß (1-42) aggregation in hippocampal regions of mouse brains. Furthermore, IHC and western blot results suggested antioxidant (Keap-1/Nrf-2/HO-1), anti-inflammatory (TLR-4/NF-kB) and anti-apoptotic (Bcl-2/Bax/Caspase-3) effect of Bergenin. Moreover, a decrease in Annexin V/PI-stained hippocampal cells suggested its effect against neurodegeneration. The histopathological changes were reversed significantly by Bergenin. In addition, a remarkable increase in antioxidant level with suppression of pro-inflammatory cytokines, oxidative stress and nitric oxide production were observed in specific regions of the mouse brains.


Assuntos
Benzopiranos/farmacologia , Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Transtornos da Memória/etiologia , Transtornos da Memória/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Serina Endopeptidases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Benzopiranos/química , Biomarcadores , Linhagem Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Ligação de Hidrogênio , Mediadores da Inflamação/metabolismo , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/diagnóstico , Transtornos da Memória/tratamento farmacológico , Camundongos , Camundongos Transgênicos , Modelos Moleculares , Estrutura Molecular , Atividade Motora/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Relação Estrutura-Atividade , Resultado do Tratamento
4.
Int J Mol Sci ; 22(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208315

RESUMO

Onset and progression of Alzheimer's disease (AD) pathophysiology differs between brain regions. The neocortex, for example, is a brain region that is affected very early during AD. NMDA receptors (NMDARs) are involved in mediating amyloid beta (Aß) toxicity. NMDAR expression, on the other hand, can be affected by Aß. We tested whether the high vulnerability of neocortical neurons for Aß-toxicity may result from specific NMDAR expression profiles or from a particular regulation of NMDAR expression by Aß. Electrophysiological analyses suggested that pyramidal cells of 6-months-old wildtype mice express mostly GluN1/GluN2A NMDARs. While synaptic NMDAR-mediated currents are unaltered in 5xFAD mice, extrasynaptic NMDARs seem to contain GluN1/GluN2A and GluN1/GluN2A/GluN2B. We used conditional GluN1 and GluN2B knockout mice to investigate whether NMDARs contribute to Aß-toxicity. Spine number was decreased in pyramidal cells of 5xFAD mice and increased in neurons with 3-week virus-mediated Aß-overexpression. NMDARs were required for both Aß-mediated changes in spine number and functional synapses. Thus, our study gives novel insights into the Aß-mediated regulation of NMDAR expression and the role of NMDARs in Aß pathophysiology in the somatosensory cortex.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Espinhas Dendríticas/metabolismo , Neocórtex/metabolismo , Neurônios/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapses/metabolismo , Doença de Alzheimer , Animais , Potenciais Pós-Sinápticos Excitadores , Camundongos Transgênicos , Subunidades Proteicas/metabolismo , Células Piramidais/metabolismo , Córtex Somatossensorial/metabolismo
5.
Int J Mol Sci ; 22(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208383

RESUMO

Hereditary retinal degenerations like retinitis pigmentosa (RP) are among the leading causes of blindness in younger patients. To enable in vivo investigation of cellular and molecular mechanisms responsible for photoreceptor cell death and to allow testing of therapeutic strategies that could prevent retinal degeneration, animal models have been created. In this study, we deeply characterized the transcriptional profile of mice carrying the transgene rhodopsin V20G/P23H/P27L (VPP), which is a model for autosomal dominant RP. We examined the degree of photoreceptor degeneration and studied the impact of the VPP transgene-induced retinal degeneration on the transcriptome level of the retina using next generation RNA sequencing (RNASeq) analyses followed by weighted correlation network analysis (WGCNA). We furthermore identified cellular subpopulations responsible for some of the observed dysregulations using in situ hybridizations, immunofluorescence staining, and 3D reconstruction. Using RNASeq analysis, we identified 9256 dysregulated genes and six significantly associated gene modules in the subsequently performed WGCNA. Gene ontology enrichment showed, among others, dysregulation of genes involved in TGF-ß regulated extracellular matrix organization, the (ocular) immune system/response, and cellular homeostasis. Moreover, heatmaps confirmed clustering of significantly dysregulated genes coding for components of the TGF-ß, G-protein activated, and VEGF signaling pathway. 3D reconstructions of immunostained/in situ hybridized sections revealed retinal neurons and Müller cells as the major cellular population expressing representative components of these signaling pathways. The predominant effect of VPP-induced photoreceptor degeneration pointed towards induction of neuroinflammation and the upregulation of neuroprotective pathways like TGF-ß, G-protein activated, and VEGF signaling. Thus, modulation of these processes and signaling pathways might represent new therapeutic options to delay the degeneration of photoreceptors in diseases like RP.


Assuntos
Perfilação da Expressão Gênica , Neuroproteção/genética , Retinite Pigmentosa/genética , Transcrição Genética , Regulação para Cima/genética , Animais , Quimiocina CCL2/metabolismo , Feminino , Proteínas de Ligação ao GTP/metabolismo , Redes Reguladoras de Genes , Proteína Glial Fibrilar Ácida/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Neuroglia/metabolismo , Degeneração Retiniana/complicações , Degeneração Retiniana/patologia , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/patologia , Rodopsina/genética , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Proc Natl Acad Sci U S A ; 118(29)2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34210738

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection continues to be a serious global public health threat. The 3C-like protease (3CLpro) is a virus protease encoded by SARS-CoV-2, which is essential for virus replication. We have previously reported a series of small-molecule 3CLpro inhibitors effective for inhibiting replication of human coronaviruses including SARS-CoV-2 in cell culture and in animal models. Here we generated a series of deuterated variants of a 3CLpro inhibitor, GC376, and evaluated the antiviral effect against SARS-CoV-2. The deuterated GC376 displayed potent inhibitory activity against SARS-CoV-2 in the enzyme- and the cell-based assays. The K18-hACE2 mice develop mild to lethal infection commensurate with SARS-CoV-2 challenge doses and were proposed as a model for efficacy testing of antiviral agents. We treated lethally infected mice with a deuterated derivative of GC376. Treatment of K18-hACE2 mice at 24 h postinfection with a derivative (compound 2) resulted in increased survival of mice compared to vehicle-treated mice. Lung virus titers were decreased, and histopathological changes were ameliorated in compound 2-treated mice compared to vehicle-treated mice. Structural investigation using high-resolution crystallography illuminated binding interactions of 3CLpro of SARS-CoV-2 and SARS-CoV with deuterated variants of GC376. Taken together, deuterated GC376 variants have excellent potential as antiviral agents against SARS-CoV-2.


Assuntos
Antivirais/uso terapêutico , COVID-19/tratamento farmacológico , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases Semelhantes à Papaína de Coronavírus/antagonistas & inibidores , Inibidores de Proteases/uso terapêutico , Pirrolidinas/uso terapêutico , SARS-CoV-2/efeitos dos fármacos , Enzima de Conversão de Angiotensina 2/genética , Animais , Antivirais/síntese química , Antivirais/química , Antivirais/farmacologia , COVID-19/patologia , Proteases 3C de Coronavírus/química , Proteases Semelhantes à Papaína de Coronavírus/química , Cristalografia por Raios X , Deutério , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Pulmão/patologia , Camundongos , Camundongos Transgênicos , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteases/síntese química , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Conformação Proteica , Pirrolidinas/química , SARS-CoV-2/enzimologia , Transgenes
7.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206229

RESUMO

The reinvigoration of anti-cancer immunity by immune checkpoint therapies has greatly improved cancer treatment. In chronic lymphocytic leukemia (CLL), patients as well as in the Tcl1 mouse model for CLL, PD1-expressing, exhausted T cells significantly expand alongside CLL development; nevertheless, PD1 inhibition has no clinical benefit. Hence, exhausted T cells are either not activatable by simple PD1 blocking in CLL and/or only an insufficient number of exhausted T cells are CLL-specific. In this study, we examined the latter hypothesis by exploiting the Tcl1 transgenic CLL mouse model in combination with TCR transgene expression specific for a non-cancer antigen. Following CLL tumor development, increased PD1 levels were detected on non-CLL specific T cells that seem dependent on the presence of (tumor-) antigen-specific T cells. Transcriptome analysis confirmed a similar exhaustion phenotype of non-CLL specific and endogenous PD1pos T cells. Our results indicate that in the CLL mouse model, a substantial fraction of non-CLL specific T cells becomes exhausted during disease progression in a bystander effect. These findings have important implications for the general efficacy assessment of immune checkpoint therapies in CLL.


Assuntos
Leucemia Linfocítica Crônica de Células B/fisiopatologia , Proteínas Proto-Oncogênicas/genética , Linfócitos T/imunologia , Animais , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Leucemia Linfocítica Crônica de Células B/imunologia , Camundongos , Camundongos Transgênicos
8.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206322

RESUMO

Increasing epidemiological evidence highlights the association between systemic insulin resistance and Alzheimer's disease (AD). As insulin resistance can be caused by high-stress hormone levels and since hypercortisolism appears to be an important risk factor of AD, we aimed to investigate the systemic insulin functionality and circulating stress hormone levels in a mutant humanized amyloid precursor protein (APP) overexpressing (hAPP23+/-) AD mouse model. Memory and spatial learning of male hAPP23+/- and C57BL/6 (wild type, WT) mice were assessed by a Morris Water Maze (MWM) test at the age of 4 and 12 months. The systemic metabolism was examined by intraperitoneal glucose and insulin tolerance tests (GTT, ITT). Insulin and corticosterone levels were determined in serum. In the hippocampus, parietal and occipital cortex of hAPP23+/- brains, amyloid-beta (Aß) deposits were present at 12 months of age. MWM demonstrated a cognitive decline in hAPP23+/- mice at 12 but not at 4 months, evidenced by increasing total path lengths and deteriorating probe trials compared to WT mice. hAPP23+/- animals presented increased serum corticosterone levels compared to WT mice at both 4 and 12 months. hAPP23+/- mice exhibited peripheral insulin resistance compared to WT mice at 4 months, which stabilized at 12 months of age. Serum insulin levels were similar between genotypes at 4 months of age but were significantly higher in hAPP23+/- mice at 12 months of age. Peripheral glucose homeostasis remained unchanged. These results indicate that peripheral insulin resistance combined with elevated circulating stress hormone levels could be potential biomarkers of the pre-symptomatic phase of AD.


Assuntos
Doença de Alzheimer/sangue , Biomarcadores/sangue , Disfunção Cognitiva , Corticosterona/sangue , Resistência à Insulina , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Síndrome de Cushing/complicações , Modelos Animais de Doenças , Insulina/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
9.
Int J Mol Sci ; 22(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208498

RESUMO

CYP1B1 loss of function (LoF) is the main known genetic alteration present in recessive primary congenital glaucoma (PCG), an infrequent disease characterized by delayed embryonic development of the ocular iridocorneal angle; however, the underlying molecular mechanisms are poorly understood. To model CYP1B1 LoF underlying PCG, we developed a cyp1b1 knockout (KO) zebrafish line using CRISPR/Cas9 genome editing. This line carries the c.535_667del frameshift mutation that results in the 72% mRNA reduction with the residual mRNA predicted to produce an inactive truncated protein (p.(His179Glyfs*6)). Microphthalmia and jaw maldevelopment were observed in 23% of F0 somatic mosaic mutant larvae (144 hpf). These early phenotypes were not detected in cyp1b1-KO F3 larvae (144 hpf), but 27% of adult (four months) zebrafish exhibited uni- or bilateral craniofacial alterations, indicating the existence of incomplete penetrance and variable expressivity. These phenotypes increased to 86% in the adult offspring of inbred progenitors with craniofacial defects. No glaucoma-related phenotypes were observed in cyp1b1 mutants. Transcriptomic analyses of the offspring (seven dpf) of cyp1b1-KO progenitors with adult-onset craniofacial defects revealed functionally enriched differentially expressed genes related to extracellular matrix and cell adhesion, cell growth and proliferation, lipid metabolism (retinoids, steroids and fatty acids and oxidation-reduction processes that include several cytochrome P450 genes) and inflammation. In summary, this study shows the complexity of the phenotypes and molecular pathways associated with cyp1b1 LoF, with species dependency, and provides evidence for the dysregulation of extracellular matrix gene expression as one of the mechanisms underlying the pathogenicity associated with cyp1b1 disruption.


Assuntos
Anormalidades Craniofaciais/genética , Anormalidades Craniofaciais/metabolismo , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1B1/metabolismo , Matriz Extracelular/genética , Estudos de Associação Genética , Metabolismo dos Lipídeos/genética , Animais , Matriz Extracelular/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Predisposição Genética para Doença , Camundongos Transgênicos , Peixe-Zebra
10.
Nat Protoc ; 16(7): 3241-3263, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34075229

RESUMO

Measurements of neuronal activity across brain areas are important for understanding the neural correlates of cognitive and motor processes such as attention, decision-making and action selection. However, techniques that allow cellular resolution measurements are expensive and require a high degree of technical expertise, which limits their broad use. Wide-field imaging of genetically encoded indicators is a high-throughput, cost-effective and flexible approach to measure activity of specific cell populations with high temporal resolution and a cortex-wide field of view. Here we outline our protocol for assembling a wide-field macroscope setup, performing surgery to prepare the intact skull and imaging neural activity chronically in behaving, transgenic mice. Further, we highlight a processing pipeline that leverages novel, cloud-based methods to analyze large-scale imaging datasets. The protocol targets laboratories that are seeking to build macroscopes, optimize surgical procedures for long-term chronic imaging and/or analyze cortex-wide neuronal recordings. The entire protocol, including steps for assembly and calibration of the macroscope, surgical preparation, imaging and data analysis, requires a total of 8 h. It is designed to be accessible to laboratories with limited expertise in imaging methods or interest in high-throughput imaging during behavior.


Assuntos
Comportamento Animal/fisiologia , Córtex Cerebral/citologia , Córtex Cerebral/diagnóstico por imagem , Imageamento Tridimensional/métodos , Animais , Artefatos , Hemodinâmica/fisiologia , Camundongos Transgênicos , Crânio/cirurgia
11.
Nat Commun ; 12(1): 3416, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099706

RESUMO

APOE and Trem2 are major genetic risk factors for Alzheimer's disease (AD), but how they affect microglia response to Aß remains unclear. Here we report an APOE isoform-specific phospholipid signature with correlation between human APOEε3/3 and APOEε4/4 AD brain and lipoproteins from astrocyte conditioned media of APOE3 and APOE4 mice. Using preclinical AD mouse models, we show that APOE3 lipoproteins, unlike APOE4, induce faster microglial migration towards injected Aß, facilitate Aß uptake, and ameliorate Aß effects on cognition. Bulk and single-cell RNA-seq demonstrate that, compared to APOE4, cortical infusion of APOE3 lipoproteins upregulates a higher proportion of genes linked to an activated microglia response, and this trend is augmented by TREM2 deficiency. In vitro, lack of TREM2 decreases Aß uptake by APOE4-treated microglia only, suggesting TREM2-APOE interaction. Our study elucidates phenotypic and transcriptional differences in microglial response to Aß mediated by APOE3 or APOE4 lipoproteins in preclinical models of AD.


Assuntos
Doença de Alzheimer/patologia , Apolipoproteína E3/metabolismo , Apolipoproteína E4/metabolismo , Encéfalo/patologia , Microglia/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Apolipoproteína E3/administração & dosagem , Apolipoproteína E3/genética , Apolipoproteína E4/administração & dosagem , Apolipoproteína E4/genética , Encéfalo/citologia , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Mutação , Fosfolipídeos/metabolismo , Presenilina-1/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA-Seq , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo
12.
Nat Commun ; 12(1): 3414, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099731

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) patients have a 5-year survival rate of only 8% largely due to late diagnosis and insufficient therapeutic options. Neutrophils are among the most abundant immune cell type within the PDAC tumor microenvironment (TME), and are associated with a poor clinical prognosis. However, despite recent advances in understanding neutrophil biology in cancer, therapies targeting tumor-associated neutrophils are lacking. Here, we demonstrate, using pre-clinical mouse models of PDAC, that lorlatinib attenuates PDAC progression by suppressing neutrophil development and mobilization, and by modulating tumor-promoting neutrophil functions within the TME. When combined, lorlatinib also improves the response to anti-PD-1 blockade resulting in more activated CD8 + T cells in PDAC tumors. In summary, this study identifies an effect of lorlatinib in modulating tumor-associated neutrophils, and demonstrates the potential of lorlatinib to treat PDAC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Inibidores de Checkpoint Imunológico/farmacologia , Lactamas Macrocíclicas/farmacologia , Neutrófilos/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral/transplante , Modelos Animais de Doenças , Sinergismo Farmacológico , Feminino , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Lactamas Macrocíclicas/uso terapêutico , Ativação Linfocitária/efeitos dos fármacos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Masculino , Camundongos , Camundongos Transgênicos , Neutrófilos/imunologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
13.
Nat Commun ; 12(1): 3253, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059674

RESUMO

Muscle stem cell function has been suggested to be regulated by Acetyl-CoA and NAD+ availability, but the mechanisms remain unclear. Here we report the identification of two acetylation sites on PAX7 that positively regulate its transcriptional activity. Lack of PAX7 acetylation reduces DNA binding, specifically to the homeobox motif. The acetyltransferase MYST1 stimulated by Acetyl-CoA, and the deacetylase SIRT2 stimulated by NAD +, are identified as direct regulators of PAX7 acetylation and asymmetric division in muscle stem cells. Abolishing PAX7 acetylation in mice using CRISPR/Cas9 mutagenesis leads to an expansion of the satellite stem cell pool, reduced numbers of asymmetric stem cell divisions, and increased numbers of oxidative IIA myofibers. Gene expression analysis confirms that lack of PAX7 acetylation preferentially affects the expression of target genes regulated by homeodomain binding motifs. Therefore, PAX7 acetylation status regulates muscle stem cell function and differentiation potential to facilitate metabolic adaptation of muscle tissue.


Assuntos
Autorrenovação Celular/genética , Músculo Esquelético/lesões , Fator de Transcrição PAX7/metabolismo , Regeneração/genética , Células Satélites de Músculo Esquelético/fisiologia , Acetilação , Animais , Células COS , Sistemas CRISPR-Cas , Cardiotoxinas/administração & dosagem , Cardiotoxinas/toxicidade , Diferenciação Celular/genética , Chlorocebus aethiops , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , Músculo Esquelético/citologia , Músculo Esquelético/efeitos dos fármacos , Mutagênese , Cultura Primária de Células , Regiões Promotoras Genéticas , Células Sf9 , Sirtuína 2/genética , Sirtuína 2/metabolismo , Spodoptera , Ativação Transcricional
14.
Int J Mol Sci ; 22(9)2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-34063118

RESUMO

Mesenchymal stem cells (MSCs) have been widely used in therapeutic applications for many decades. However, more and more evidence suggests that factors such as the site of origin and pre-implantation treatment have a crucial impact on the result. This study investigates the role of freshly isolated MSCs in the lacrimal gland after allogeneic transplantation. For this purpose, MSCs from transgenic GFP mice were isolated and transplanted into allogeneic and syngeneic recipients. While the syngeneic MSCs maintained a spherical shape, allogeneic MSCs engrafted into the tissue as spindle-shaped cells in the interstitial stroma. Furthermore, the MSCs produced collagen type I in more than 85% to 95% of the detected GFP+ MSCs in the recipients of both models, supposedly contributing to pathogenic fibrosis in allogeneic recipients compared to syngeneic models. These findings indicate that allogeneic MSCs act completely differently from syngeneic MSCs, highlighting the importance of understanding the exact mechanisms behind MSCs.


Assuntos
Transplante de Medula Óssea , Colágeno Tipo I/biossíntese , Células-Tronco Mesenquimais/metabolismo , Animais , Aparelho Lacrimal/citologia , Células-Tronco Mesenquimais/citologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Transplante Homólogo , Transplante Isogênico
15.
Int J Mol Sci ; 22(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065168

RESUMO

Increasing evidence links metabolic disorders with neurodegenerative processes including Alzheimer's disease (AD). Late AD is associated with amyloid (Aß) plaque accumulation, neuroinflammation, and central insulin resistance. Here, a humanized AD model, the 5xFAD mouse model, was used to further explore food intake, energy expenditure, neuroinflammation, and neuroendocrine signaling in the hypothalamus. Experiments were performed on 6-month-old male and female full transgenic (Tg5xFAD/5xFAD), heterozygous (Tg5xFAD/-), and non-transgenic (Non-Tg) littermates. Although histological analysis showed absence of Aß plaques in the hypothalamus of 5xFAD mice, this brain region displayed increased protein levels of GFAP and IBA1 in both Tg5xFAD/- and Tg5xFAD/5xFAD mice and increased expression of IL-1ß in Tg5xFAD/5xFAD mice, suggesting neuroinflammation. This condition was accompanied by decreased body weight, food intake, and energy expenditure in both Tg5xFAD/- and Tg5xFAD/5xFAD mice. Negative energy balance was associated with altered circulating levels of insulin, GLP-1, GIP, ghrelin, and resistin; decreased insulin and leptin hypothalamic signaling; dysregulation in main metabolic sensors (phosphorylated IRS1, STAT5, AMPK, mTOR, ERK2); and neuropeptides controlling energy balance (NPY, AgRP, orexin, MCH). These results suggest that glial activation and metabolic dysfunctions in the hypothalamus of a mouse model of AD likely result in negative energy balance, which may contribute to AD pathogenesis development.


Assuntos
Doença de Alzheimer/metabolismo , Metabolismo Energético/fisiologia , Hipotálamo/metabolismo , Doenças Metabólicas/metabolismo , Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Proteínas Amiloidogênicas/metabolismo , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Feminino , Polipeptídeo Inibidor Gástrico/metabolismo , Grelina/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Insulina/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Placa Amiloide/metabolismo , Resistina/metabolismo
16.
Int J Mol Sci ; 22(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073630

RESUMO

Motor neuron diseases (MNDs) are neurodegenerative disorders characterized by upper and/or lower MN loss. MNDs include amyotrophic lateral sclerosis (ALS), spinal muscular atrophy (SMA), and spinal and bulbar muscular atrophy (SBMA). Despite variability in onset, progression, and genetics, they share a common skeletal muscle involvement, suggesting that it could be a primary site for MND pathogenesis. Due to the key role of muscle-specific microRNAs (myomiRs) in skeletal muscle development, by real-time PCR we investigated the expression of miR-206, miR-133a, miR-133b, and miR-1, and their target genes, in G93A-SOD1 ALS, Δ7SMA, and KI-SBMA mouse muscle during disease progression. Further, we analyzed their expression in serum of SOD1-mutated ALS, SMA, and SBMA patients, to demonstrate myomiR role as noninvasive biomarkers. Our data showed a dysregulation of myomiRs and their targets, in ALS, SMA, and SBMA mice, revealing a common pathogenic feature associated with muscle impairment. A similar myomiR signature was observed in patients' sera. In particular, an up-regulation of miR-206 was identified in both mouse muscle and serum of human patients. Our overall findings highlight the role of myomiRs as promising biomarkers in ALS, SMA, and SBMA. Further investigations are needed to explore the potential of myomiRs as therapeutic targets for MND treatment.


Assuntos
Esclerose Amiotrófica Lateral , Atrofia Bulboespinal Ligada ao X , MicroRNAs , Mutação de Sentido Incorreto , Superóxido Dismutase-1 , Superóxido Dismutase , Substituição de Aminoácidos , Esclerose Amiotrófica Lateral/genética , Esclerose Amiotrófica Lateral/metabolismo , Animais , Atrofia Bulboespinal Ligada ao X/genética , Atrofia Bulboespinal Ligada ao X/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , MicroRNAs/genética , MicroRNAs/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo
17.
Yonsei Med J ; 62(7): 622-630, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34164960

RESUMO

PURPOSE: Expression of organic anion transporting polypeptides (OATPs) 1B1/1B3 in hepatocellular carcinoma (HCC) induces a paradoxical enhancement of gadoxetic acid on liver magnetic resonance imaging (MRI). We examined the expression profile of OATPs with regard to tumor differentiation in a genetically modified H-Ras 12V mouse model of spontaneous HCC that undergoes multistep hepatocarcinogenesis with minimal inter-individual variation. MATERIALS AND METHODS: Tumor nodules were harvested from transgenic H-Ras 12V mice. Hematoxylin and eosin-stained slides were examined for tumor differentiation and high-grade pathological components (tumor necrosis, thickened trabeculae, or vascular invasion). Immunohistochemistry of OATP 1B1/1B3 was performed, and OATP expression was assessed. RESULTS: We examined well-differentiated HCCs (n=59) in which high-grade pathological components were absent (n=49) or present (n=10). Among the well-differentiated HCCs without high-grade pathological components (n=49), OATP expression was negative, weak positive, and moderate positive in 23, 17, and nine cases, respectively. Among the well-differentiated HCCs with high-grade pathological components (n=10), OATP expression was negative, weak positive, and moderate positive in one, two, and seven cases, respectively. The ratio of positive OATP 1B1/1B3 expressing tumors was higher in HCCs with high-grade pathological components than in those without high-grade pathological components (p=0.004). CONCLUSION: Our findings support those of previous clinical studies that have reported the frequent appearance of gadoxetic acid-enhanced MRI in moderately differentiated HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transportadores de Ânions Orgânicos , Animais , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/genética , Meios de Contraste , Gadolínio DTPA , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/genética , Imageamento por Ressonância Magnética , Camundongos , Camundongos Transgênicos , Peptídeos , Estudos Retrospectivos
18.
Nat Commun ; 12(1): 3707, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140478

RESUMO

While the major drivers of melanoma initiation, including activation of NRAS/BRAF and loss of PTEN or CDKN2A, have been identified, the role of key transcription factors that impose altered transcriptional states in response to deregulated signaling is not well understood. The POU domain transcription factor BRN2 is a key regulator of melanoma invasion, yet its role in melanoma initiation remains unknown. Here, in a BrafV600E PtenF/+ context, we show that BRN2 haplo-insufficiency promotes melanoma initiation and metastasis. However, metastatic colonization is less efficient in the absence of Brn2. Mechanistically, BRN2 directly induces PTEN expression and in consequence represses PI3K signaling. Moreover, MITF, a BRN2 target, represses PTEN transcription. Collectively, our results suggest that on a PTEN heterozygous background somatic deletion of one BRN2 allele and temporal regulation of the other allele elicits melanoma initiation and progression.


Assuntos
Carcinogênese/metabolismo , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Genes Supressores de Tumor , Proteínas de Homeodomínio/metabolismo , Melanoma/metabolismo , Fatores do Domínio POU/metabolismo , Neoplasias Cutâneas/metabolismo , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Estudos de Coortes , Variações do Número de Cópias de DNA , Progressão da Doença , Técnicas de Silenciamento de Genes , Haploinsuficiência , Proteínas de Homeodomínio/genética , Humanos , Imuno-Histoquímica , Melanoma/genética , Melanoma/mortalidade , Melanoma/secundário , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Análise em Microsséries , Fator de Transcrição Associado à Microftalmia/metabolismo , Mutação , Fatores do Domínio POU/genética , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética , RNA Interferente Pequeno , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/secundário
19.
Sci Immunol ; 6(60)2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34145066

RESUMO

The nutrient-sensing mammalian target of rapamycin (mTOR) is integral to cell fate decisions after T cell activation. Sustained mTORC1 activity favors the generation of terminally differentiated effector T cells instead of follicular helper and memory T cells. This is particularly pertinent for T cell responses of older adults who have sustained mTORC1 activation despite dysfunctional lysosomes. Here, we show that lysosome-deficient T cells rely on late endosomes rather than lysosomes as an mTORC1 activation platform, where mTORC1 is activated by sensing cytosolic amino acids. T cells from older adults have an increased expression of the plasma membrane leucine transporter SLC7A5 to provide a cytosolic amino acid source. Hence, SLC7A5 and VPS39 deficiency (a member of the HOPS complex promoting early to late endosome conversion) substantially reduced mTORC1 activities in T cells from older but not young individuals. Late endosomal mTORC1 is independent of the negative-feedback loop involving mTORC1-induced inactivation of the transcription factor TFEB that controls expression of lysosomal genes. The resulting sustained mTORC1 activation impaired lysosome function and prevented lysosomal degradation of PD-1 in CD4+ T cells from older adults, thereby inhibiting their proliferative responses. VPS39 silencing of human T cells improved their expansion to pertussis and to SARS-CoV-2 peptides in vitro. Furthermore, adoptive transfer of CD4+ Vps39-deficient LCMV-specific SMARTA cells improved germinal center responses, CD8+ memory T cell generation, and recall responses to infection. Thus, curtailing late endosomal mTORC1 activity is a promising strategy to enhance T cell immunity.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , Endossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , SARS-CoV-2/metabolismo , Transdução de Sinais/genética , Transferência Adotiva/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Proteínas Relacionadas à Autofagia/deficiência , Proteínas Relacionadas à Autofagia/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , COVID-19/virologia , Células Cultivadas , Feminino , Proteína Forkhead Box O1/deficiência , Proteína Forkhead Box O1/genética , Voluntários Saudáveis , Humanos , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Lisossomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transdução de Sinais/imunologia , Transfecção , Proteínas de Transporte Vesicular/deficiência , Proteínas de Transporte Vesicular/genética , Adulto Jovem
20.
PLoS One ; 16(6): e0253487, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34161386

RESUMO

Although SARS-CoV-2-neutralizing antibodies are promising therapeutics against COVID-19, little is known about their mechanism(s) of action or effective dosing windows. We report the generation and development of SC31, a potent SARS-CoV-2 neutralizing antibody, isolated from a convalescent patient. Antibody-mediated neutralization occurs via an epitope within the receptor-binding domain of the SARS-CoV-2 Spike protein. SC31 exhibited potent anti-SARS-CoV-2 activities in multiple animal models. In SARS-CoV-2 infected K18-human ACE2 transgenic mice, treatment with SC31 greatly reduced viral loads and attenuated pro-inflammatory responses linked to the severity of COVID-19. Importantly, a comparison of the efficacies of SC31 and its Fc-null LALA variant revealed that the optimal therapeutic efficacy of SC31 requires Fc-mediated effector functions that promote IFNγ-driven anti-viral immune responses, in addition to its neutralization ability. A dose-dependent efficacy of SC31 was observed down to 5mg/kg when administered before viral-induced lung inflammatory responses. In addition, antibody-dependent enhancement was not observed even when infected mice were treated with SC31 at sub-therapeutic doses. In SARS-CoV-2-infected hamsters, SC31 treatment significantly prevented weight loss, reduced viral loads, and attenuated the histopathology of the lungs. In rhesus macaques, the therapeutic potential of SC31 was evidenced through the reduction of viral loads in both upper and lower respiratory tracts to undetectable levels. Together, the results of our preclinical studies demonstrated the therapeutic efficacy of SC31 in three different models and its potential as a COVID-19 therapeutic candidate.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , COVID-19/terapia , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/genética , Animais , Anticorpos Neutralizantes/metabolismo , COVID-19/imunologia , COVID-19/virologia , Quimiocinas/sangue , Quimiocinas/genética , Chlorocebus aethiops , Convalescença , Cricetinae , Citocinas/sangue , Citocinas/genética , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Humanos , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/imunologia , Imunoglobulina G/isolamento & purificação , Macaca mulatta , Masculino , Camundongos Transgênicos , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Vero , Carga Viral
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