Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 7.030
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Immunity ; 57(7): 1696-1709.e10, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38878770

RESUMO

Aicardi-Goutières syndrome (AGS) is an autoinflammatory disease characterized by aberrant interferon (IFN)-α production. The major cause of morbidity in AGS is brain disease, yet the primary source and target of neurotoxic IFN-α remain unclear. Here, we demonstrated that the brain was the primary source of neurotoxic IFN-α in AGS and confirmed the neurotoxicity of intracerebral IFN-α using astrocyte-driven Ifna1 misexpression in mice. Using single-cell RNA sequencing, we demonstrated that intracerebral IFN-α-activated receptor (IFNAR) signaling within cerebral endothelial cells caused a distinctive cerebral small vessel disease similar to that observed in individuals with AGS. Magnetic resonance imaging (MRI) and single-molecule ELISA revealed that central and not peripheral IFN-α was the primary determinant of microvascular disease in humans. Ablation of endothelial Ifnar1 in mice rescued microvascular disease, stopped the development of diffuse brain disease, and prolonged lifespan. These results identify the cerebral microvasculature as a primary mediator of IFN-α neurotoxicity in AGS, representing an accessible target for therapeutic intervention.


Assuntos
Encéfalo , Interferon-alfa , Microvasos , Malformações do Sistema Nervoso , Receptor de Interferon alfa e beta , Animais , Humanos , Camundongos , Interferon-alfa/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Receptor de Interferon alfa e beta/metabolismo , Receptor de Interferon alfa e beta/genética , Microvasos/patologia , Malformações do Sistema Nervoso/genética , Doenças Autoimunes do Sistema Nervoso/imunologia , Células Endoteliais/metabolismo , Camundongos Knockout , Masculino , Feminino , Transdução de Sinais , Camundongos Endogâmicos C57BL , Astrócitos/metabolismo , Modelos Animais de Doenças
2.
CA Cancer J Clin ; 70(2): 86-104, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31944278

RESUMO

Cancer immunotherapies, including checkpoint inhibitors and adoptive cell therapy, manipulate the immune system to recognize and attack cancer cells. These therapies have the potential to induce durable responses in multiple solid and hematologic malignancies and thus have transformed treatment algorithms for numerous tumor types. Cancer immunotherapies lead to unique toxicity profiles distinct from the toxicities of other cancer therapies, depending on their mechanism of action. These toxicities often require specific management, which can include steroids and immune-modulating therapy and for which consensus guidelines have been published. This review will focus on the toxicities of checkpoint inhibitors and chimeric antigen receptor T cells, including pathophysiology, diagnosis, and management.


Assuntos
Fatores Imunológicos/uso terapêutico , Imunoterapia/métodos , Neoplasias/terapia , Humanos
3.
Hum Mol Genet ; 33(10): 860-871, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38324746

RESUMO

Neuromuscular disorders caused by dysfunction of the mitochondrial respiratory chain are common, severe and untreatable. We recovered a number of mitochondrial genes, including electron transport chain components, in a large forward genetic screen for mutations causing age-related neurodegeneration in the context of proteostasis dysfunction. We created a model of complex I deficiency in the Drosophila retina to probe the role of protein degradation abnormalities in mitochondrial encephalomyopathies. Using our genetic model, we found that complex I deficiency regulates both the ubiquitin/proteasome and autophagy/lysosome arms of the proteostasis machinery. We further performed an in vivo kinome screen to uncover new and potentially druggable mechanisms contributing to complex I related neurodegeneration and proteostasis failure. Reduction of RIOK kinases and the innate immune signaling kinase pelle prevented neurodegeneration in complex I deficiency animals. Genetically targeting oxidative stress, but not RIOK1 or pelle knockdown, normalized proteostasis markers. Our findings outline distinct pathways controlling neurodegeneration and protein degradation in complex I deficiency and introduce an experimentally facile model in which to study these debilitating and currently treatment-refractory disorders.


Assuntos
Modelos Animais de Doenças , Proteínas de Drosophila , Complexo I de Transporte de Elétrons , Complexo I de Transporte de Elétrons/deficiência , Mitocôndrias , Doenças Mitocondriais , Proteostase , Animais , Complexo I de Transporte de Elétrons/genética , Complexo I de Transporte de Elétrons/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/genética , Mitocôndrias/patologia , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/deficiência , Doenças Mitocondriais/genética , Doenças Mitocondriais/metabolismo , Doenças Mitocondriais/patologia , Humanos , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/genética , Autofagia/genética , Estresse Oxidativo/genética , Drosophila melanogaster/genética , Mutação , Lisossomos/metabolismo , Lisossomos/genética , Drosophila/genética , Drosophila/metabolismo , Transdução de Sinais
4.
EMBO Rep ; 25(10): 4337-4357, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39242776

RESUMO

Despite the efficacy of highly active antiretroviral therapy in controlling the incidence and mortality of AIDS, effective interventions for HIV-1-induced neurological damage and cognitive impairment remain elusive. In this study, we found that HIV-1 infection can induce proteolytic cleavage and aberrant aggregation of TAR DNA-binding protein 43 (TDP-43), a pathological protein associated with various severe neurological disorders. The HIV-1 accessory protein Vpu was found to be responsible for the cleavage of TDP-43, as ectopic expression of Vpu alone was sufficient to induce TDP-43 cleavage, whereas HIV-1 lacking Vpu failed to cleave TDP-43. Mechanistically, the cleavage of TDP-43 at Asp89 by HIV-1 relies on Vpu-mediated activation of Caspase 3, and pharmacological inhibition of Caspase 3 activity effectively suppressed the HIV-1-induced aggregation and neurotoxicity of TDP-43. Overall, these results suggest that TDP-43 is a conserved host target of HIV-1 Vpu and provide evidence for the involvement of TDP-43 dysregulation in the neural pathogenesis of HIV-1.


Assuntos
Caspase 3 , Proteínas de Ligação a DNA , HIV-1 , Proteínas do Vírus da Imunodeficiência Humana , Proteólise , Proteínas Virais Reguladoras e Acessórias , Humanos , Caspase 3/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Células HEK293 , Infecções por HIV/metabolismo , Infecções por HIV/virologia , Infecções por HIV/tratamento farmacológico , Proteínas do Vírus da Imunodeficiência Humana/metabolismo , Proteínas do Vírus da Imunodeficiência Humana/genética , Neurônios/metabolismo , Neurônios/virologia , Proteínas Virais Reguladoras e Acessórias/metabolismo
5.
J Neurosci ; 44(14)2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38383499

RESUMO

Human endogenous retroviruses (HERVs) are associated with the pathogenesis of amyotrophic lateral sclerosis (ALS); a disease characterized by motor neuron degeneration and cell death. The HERV-K subtype HML-2 envelope protein (HERV-K Env) is expressed in the brain, spinal cord, and cerebrospinal fluid of people living with ALS and through CD98 receptor-linked interactions causes neurodegeneration. HERV-K Env-induced increases in oxidative stress are implicated in the pathogenesis of ALS, and ferrous iron (Fe2+) generates reactive oxygen species (ROS). Endolysosome stores of Fe2+ are central to iron trafficking and endolysosome deacidification releases Fe2+ into the cytoplasm. Because HERV-K Env is an arginine-rich protein that is likely endocytosed and arginine is a pH-elevating amino acid, it is important to determine HERV-K Env effects on endolysosome pH and whether HERV-K Env-induced neurotoxicity is downstream of Fe2+ released from endolysosomes. Here, we showed using SH-SY5Y human neuroblastoma cells and primary cultures of human cortical neurons (HCNs, information on age and sex was not available) that HERV-K Env (1) is endocytosed via CD98 receptors, (2) concentration dependently deacidified endolysosomes, (3) decreased endolysosome Fe2+ concentrations, (4) increased cytosolic and mitochondrial Fe2+ and ROS levels, (5) depolarized mitochondrial membrane potential, and (6) induced cell death, effects blocked by an antibody against the CD98 receptor and by the endolysosome iron chelator deferoxamine. Thus, HERV-K Env-induced increases in cytosolic and mitochondrial Fe2+ and ROS as well as cell death appear to be mechanistically caused by HERV-K Env endocytosis, endolysosome deacidification, and endolysosome Fe2+ efflux into the cytoplasm.


Assuntos
Esclerose Lateral Amiotrófica , Retrovirus Endógenos , Neuroblastoma , Síndromes Neurotóxicas , Humanos , Esclerose Lateral Amiotrófica/patologia , Ferro , Espécies Reativas de Oxigênio , Arginina
6.
J Biol Chem ; 300(5): 107253, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569938

RESUMO

Homocysteine, a sulfur-containing amino acid derived from methionine metabolism, is a known agonist of N-methyl-D-aspartate receptor (NMDAR) and is involved in neurotoxicity. Our previous findings showed that neuronal exposure to elevated homocysteine levels leads to sustained low-level increase in intracellular Ca2+, which is dependent on GluN2A subunit-containing NMDAR (GluN2A-NMDAR) stimulation. These studies further showed a role of ERK MAPK in homocysteine-GluN2A-NMDAR-mediated neuronal death. However, the intracellular mechanisms associated with such sustained GluN2A-NMDAR stimulation and subsequent Ca2+ influx have remained unexplored. Using live-cell imaging with Fluo3-AM and biochemical approaches, we show that homocysteine-GluN2A NMDAR-induced initial Ca2+ influx triggers sequential phosphorylation and subsequent activation of the proline rich tyrosine kinase 2 (Pyk2) and Src family kinases, which in turn phosphorylates GluN2A-Tyr1325 residue of GluN2A-NMDARs to maintain channel activity. The continuity of this cycle of events leads to sustained Ca2+ influx through GluN2A-NMDAR. Our findings also show that lack of activation of the regulatory tyrosine phosphatase STEP, which can limit Pyk2 and Src family kinase activity further contributes to the maintenance of this cycle. Additional studies using live-cell imaging of neurons expressing a redox-sensitive GFP targeted to the mitochondrial matrix show that treatment with homocysteine leads to a progressive increase in mitochondrial reactive oxygen species generation, which is dependent on GluN2A-NMDAR-mediated sustained ERK MAPK activation. This later finding demonstrates a novel role of GluN2A-NMDAR in homocysteine-induced mitochondrial ROS generation and highlights the role of ERK MAPK as the intermediary signaling pathway between GluN2A-NMDAR stimulation and mitochondrial reactive oxygen species generation.


Assuntos
Homocisteína , Mitocôndrias , Espécies Reativas de Oxigênio , Receptores de N-Metil-D-Aspartato , Receptores de N-Metil-D-Aspartato/metabolismo , Homocisteína/metabolismo , Homocisteína/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Mitocôndrias/metabolismo , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Cálcio/metabolismo , Fosforilação/efeitos dos fármacos , Quinase 2 de Adesão Focal/metabolismo , Quinases da Família src/metabolismo , Ratos , Camundongos , Humanos
7.
Int Immunol ; 36(2): 49-56, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-37591521

RESUMO

Adoptive immunotherapy using chimeric antigen-receptor (CAR)-engineered T cells can induce robust antitumor responses against hematologic malignancies. However, its efficacy is not durable in the majority of the patients, warranting further improvement of T-cell functions. Cytokine signaling is one of the key cascades regulating T-cell survival and effector functions. In addition to cytokines that use the common γ chain as a receptor subunit, multiple cytokines regulate T-cell functions directly or indirectly. Modulating cytokine signaling in CAR-T cells by genetic engineering is one promising strategy to augment their therapeutic efficacy. These strategies include ectopic expression of cytokines, cytokine receptors, and synthetic molecules that mimic endogenous cytokine signaling. Alternatively, autocrine IL-2 signaling can be augmented through reprogramming of CAR-T cell properties through transcriptional and epigenetic modification. On the other hand, cytokine production by CAR-T cells triggers systemic inflammatory responses, which mainly manifest as adverse events such as cytokine-release syndrome (CRS) and neurotoxicity. In addition to inhibiting direct inflammatory mediators such as IL-6 and IL-1 released from activated macrophages, suppression of T-cell-derived cytokines associated with the priming of macrophages can be accomplished through genetic modification of CAR-T cells. In this review, I will outline recently developed synthetic biology approaches to exploit cytokine signaling to enhance CAR-T cell functions. I will also discuss therapeutic target molecules to prevent or alleviate CAR-T cell-related toxicities.


Assuntos
Imunoterapia Adotiva , Receptores de Antígenos Quiméricos , Humanos , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos de Linfócitos T/genética , Citocinas/metabolismo , Terapia Baseada em Transplante de Células e Tecidos
8.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38142289

RESUMO

Concerns about the potential neurotoxic effects of anesthetics on developing brain exist. When making clinical decisions, the timing and dosage of anesthetic exposure are critical factors to consider due to their associated risks. In our study, we investigated the impact of repeated anesthetic exposures on the brain development trajectory of a cohort of rhesus monkeys (n = 26) over their first 2 yr of life, utilizing longitudinal magnetic resonance imaging data. We hypothesized that early or high-dose anesthesia exposure could negatively influence structural brain development. By employing the generalized additive mixed model, we traced the longitudinal trajectories of brain volume, cortical thickness, and white matter integrity. The interaction analysis revealed that age and cumulative anesthetic dose were variably linked to white matter integrity but not to morphometric measures. Early high-dose exposure was associated with increased mean, axial, and radial diffusivities across all white matter regions, compared to late-low-dose exposure. Our findings indicate that early or high-dose anesthesia exposure during infancy disrupts structural brain development in rhesus monkeys. Consequently, the timing of elective surgeries and procedures that require anesthesia for children and pregnant women should be strategically planned to account for the cumulative dose of volatile anesthetics, aiming to minimize the potential risks to brain development.


Assuntos
Anestésicos , Substância Branca , Humanos , Animais , Criança , Feminino , Gravidez , Macaca mulatta , Imagem de Tensor de Difusão/métodos , Encéfalo , Imageamento por Ressonância Magnética , Substância Branca/patologia , Anestésicos/toxicidade
9.
Mol Ther ; 32(9): 2979-2983, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-38532629

RESUMO

With expansion of chimeric antigen receptor (CAR) T cell therapy and broader utilization of anti-cytokine directed therapeutics for toxicity mitigation, the routine assessment of cytokines may enhance understanding of toxicity profiles, guide therapeutic interventions, and facilitate cross-trial comparisons. As specific cytokine elevations can correlate with and provide insights into CAR T cell toxicity, mitigation strategies, and response, we explored the reporting of cytokine detection methods and assessed for the correlation of cytokines to cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) across clinical trials. In this analysis, we reviewed 21 clinical trials across 60 manuscripts that featured a US Food and Drug Administration-approved CAR T cell construct or one of its predecessors. We highlight substantial variability and limited reporting of cytokine measurement platforms and panels used across CAR T cell clinical trials. Specifically, across 60 publications, 28 (46.7%) did not report any cytokine data, representing 6 of 21 (28.6%) clinical trials. In the 15 trials reporting cytokine data, at least 4 different platforms were used. Furthermore, correlation of cytokines with ICANS, CRS, and CRS severity was limited. Considering the fundamental role of cytokines in CAR T cell toxicity, our manuscript supports the need to establish standardization of cytokine measurements as a key biomarker essential to improving outcomes of CAR T cell therapy.


Assuntos
Ensaios Clínicos como Assunto , Síndrome da Liberação de Citocina , Citocinas , Imunoterapia Adotiva , Receptores de Antígenos Quiméricos , Humanos , Imunoterapia Adotiva/métodos , Imunoterapia Adotiva/efeitos adversos , Citocinas/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Receptores de Antígenos Quiméricos/imunologia , Síndrome da Liberação de Citocina/terapia , Síndrome da Liberação de Citocina/etiologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/terapia , Síndromes Neurotóxicas/diagnóstico , Receptores de Antígenos de Linfócitos T/metabolismo , Biomarcadores
10.
Cell Mol Life Sci ; 81(1): 16, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38194085

RESUMO

The nuclear loss and cytoplasmic accumulation of TDP-43 (TAR DNA/RNA binding protein 43) are pathological hallmarks of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Previously, we reported that the primate-specific cleavage of TDP-43 accounts for its cytoplasmic mislocalization in patients' brains. This prompted us to investigate further whether and how the loss of nuclear TDP-43 mediates neuropathology in primate brain. In this study, we report that TDP-43 knockdown at the similar effectiveness, induces more damage to neuronal cells in the monkey brain than rodent mouse. Importantly, the loss of TDP-43 suppresses the E3 ubiquitin ligase PJA1 expression in the monkey brain at transcriptional level, but yields an opposite upregulation of PJA1 in the mouse brain. This distinct effect is due to the species-dependent binding of nuclear TDP-43 to the unique promoter sequences of the PJA1 genes. Further analyses reveal that the reduction of PJA1 accelerates neurotoxicity, whereas overexpressing PJA1 diminishes neuronal cell death by the TDP-43 knockdown in vivo. Our findings not only uncover a novel primate-specific neurotoxic contribution to the loss of function theory of TDP-43 proteinopathy, but also underscore a potential therapeutic approach of PJA1 to the loss of nuclear TDP-43.


Assuntos
Esclerose Lateral Amiotrófica , Encéfalo , Proteínas de Ligação a DNA , Ubiquitina-Proteína Ligases , Animais , Esclerose Lateral Amiotrófica/genética , Proteínas de Ligação a DNA/genética , Haplorrinos , Transcrição Gênica , Ubiquitina-Proteína Ligases/genética , Modelos Animais de Doenças
11.
Am J Physiol Cell Physiol ; 326(6): C1735-C1752, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38618701

RESUMO

The potential neurotoxic effects of propofol, an extensively utilized anesthetic, underline the urgency to comprehend its influence on neuronal health. Insights into the role of the retinoic acid receptor-α, small nucleolar RNA host gene 1, and brain-derived neurotrophic factor (RARα-Snhg1-Bdnf) network can offer significant advancements in minimizing these effects. The study targets the exploration of the RARα and Snhg1 regulatory network's influence on Bdnf expression in the realm of propofol-induced neurotoxicity. Harnessing the Gene Expression Omnibus (GEO) database and utilizing JASPAR and RNA-Protein Interaction Prediction (RPISeq) database for projections, the study embarks on an in-depth analysis employing both in vitro and in vivo models. The findings draw a clear link between propofol-induced neurotoxicity and the amplification of RAR signaling pathways, impacting hippocampal development and apoptosis and leading to increased RARα and Snhg1 and decreased Bdnf. Propofol is inferred to accentuate neurotoxicity by heightening RARα and Snhg1 interactions, culminating in Bdnf suppression.NEW & NOTEWORTHY This study aimed to decode propofol's neurotoxic effects on the regulatory cascade, provide insights into the RARα-Snhg1-Bdnf interaction, apply extensive validation techniques, provide a detailed analysis and exploration of propofol's neurotoxicity, and offer a comprehensive approach to understanding molecular interactions.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Propofol , Receptor alfa de Ácido Retinoico , Propofol/toxicidade , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Receptor alfa de Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico/metabolismo , Animais , Humanos , Transdução de Sinais/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Síndromes Neurotóxicas/genética , Síndromes Neurotóxicas/metabolismo , Ratos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Apoptose/efeitos dos fármacos , Masculino
12.
J Cell Mol Med ; 28(4): e18118, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38332529

RESUMO

Opioids can be used for medical and non-medical purposes. Chronic pain such as cancer, as well as the frequent use of such drugs in places such as operating rooms and intensive care units, and in non-medical areas like drug abuse the effects and side effects of these drugs need to be examined in more detail. For this purpose, the effects of fentanyl and remifentanil drugs on neuroinflammation, oxidative stress and cholinesterase metabolism were investigated. Neuron cells (CRL-10742) were used for the evaluation of the toxicity of fentanyl and remifentanil. MTT, PON1 activity and total thiol levels for its effect on oxidative stress, AChE and BChE activities for its effect on the cholinergic system, and TNF, IL-8 and IL-10 gene levels for its neuroinflammation effect were determined. The highest neurotoxic dose of fentanyl and remifentanil was determined as 10 µg/mL. It was observed that the rate of neuron cells in this dose has decreased by up to 61.80% and 56.89%, respectively. The IL-8 gene expression level in both opioids was down-regulated while IL 10 gene level was up-regulated in a dose-dependent manner compared to the control. In our results, the TNF gene expression level differs between the two opioids. In the fentanyl group, it was seen to be up-regulated in a dose-dependent manner compared to the control. Fentanyl and remifentanil showed an inhibitory effect against PON1, while remifentanil showed an increase in total thiol levels. PON1, BChE and total thiol activities showed similarity with MTT.


Assuntos
Dor Crônica , Fentanila , Humanos , Fentanila/toxicidade , Remifentanil/farmacologia , Piperidinas/toxicidade , Interleucina-8 , Doenças Neuroinflamatórias , Analgésicos Opioides/toxicidade , Estresse Oxidativo , Neurônios , Dor Crônica/induzido quimicamente , Compostos de Sulfidrila , Arildialquilfosfatase
13.
J Biol Chem ; 299(7): 104881, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37269948

RESUMO

Prion protein (PrP) misfolding is the key trigger in the devastating prion diseases. Yet the sequence and structural determinants of PrP conformation and toxicity are not known in detail. Here, we describe the impact of replacing Y225 in human PrP with A225 from rabbit PrP, an animal highly resistant to prion diseases. We first examined human PrP-Y225A by molecular dynamics simulations. We next introduced human PrP in Drosophila and compared the toxicity of human PrP-WT and Y225A in the eye and in brain neurons. Y225A stabilizes the ß2-α2 loop into a 310-helix from six different conformations identified in WT and lowers hydrophobic exposure. Transgenic flies expressing PrP-Y225A exhibit less toxicity in the eye and in brain neurons and less accumulation of insoluble PrP. Overall, we determined that Y225A lowers toxicity in Drosophila assays by promoting a structured loop conformation that increases the stability of the globular domain. These findings are significant because they shed light on the key role of distal α-helix 3 on the dynamics of the loop and the entire globular domain.


Assuntos
Doenças Priônicas , Proteínas Priônicas , Animais , Humanos , Coelhos , Animais Geneticamente Modificados , Drosophila , Doenças Priônicas/genética , Proteínas Priônicas/química , Proteínas Priônicas/genética , Estabilidade Proteica , Conformação Proteica em alfa-Hélice
14.
J Biol Chem ; 299(9): 105101, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37507020

RESUMO

The C-terminal domain of the cellular prion protein (PrPC) contains two N-linked glycosylation sites, the occupancy of which impacts disease pathology. In this study, we demonstrate that glycans at these sites are required to maintain an intramolecular interaction with the N-terminal domain, mediated through a previously identified copper-histidine tether, which suppresses the neurotoxic activity of PrPC. NMR and electron paramagnetic resonance spectroscopy demonstrate that the glycans refine the structure of the protein's interdomain interaction. Using whole-cell patch-clamp electrophysiology, we further show that cultured cells expressing PrP molecules with mutated glycosylation sites display large, spontaneous inward currents, a correlate of PrP-induced neurotoxicity. Our findings establish a structural basis for the role of N-linked glycans in maintaining a nontoxic, physiological fold of PrPC.

15.
Neuroimage ; 292: 120606, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38604538

RESUMO

Radon is a naturally occurring gas that contributes significantly to radiation in the environment and is the second leading cause of lung cancer globally. Previous studies have shown that other environmental toxins have deleterious effects on brain development, though radon has not been studied as thoroughly in this context. This study examined the impact of home radon exposure on the neural oscillatory activity serving attention reorientation in youths. Fifty-six participants (ages 6-14 years) completed a classic Posner cuing task during magnetoencephalography (MEG), and home radon levels were measured for each participant. Time-frequency spectrograms indicated stronger theta (3-7 Hz, 300-800 ms), alpha (9-13 Hz, 400-900 ms), and beta responses (14-24 Hz, 400-900 ms) during the task relative to baseline. Source reconstruction of each significant oscillatory response was performed, and validity maps were computed by subtracting the task conditions (invalidly cued - validly cued). These validity maps were examined for associations with radon exposure, age, and their interaction in a linear regression design. Children with greater radon exposure showed aberrant oscillatory activity across distributed regions critical for attentional processing and attention reorientation (e.g., dorsolateral prefrontal cortex, and anterior cingulate cortex). Generally, youths with greater radon exposure exhibited a reverse neural validity effect in almost all regions and showed greater overall power relative to peers with lesser radon exposure. We also detected an interactive effect between radon exposure and age where youths with greater radon exposure exhibited divergent developmental trajectories in neural substrates implicated in attentional processing (e.g., bilateral prefrontal cortices, superior temporal gyri, and inferior parietal lobules). These data suggest aberrant, but potentially compensatory neural processing as a function of increasing home radon exposure in areas critical for attention and higher order cognition.


Assuntos
Atenção , Magnetoencefalografia , Radônio , Humanos , Adolescente , Criança , Masculino , Feminino , Radônio/toxicidade , Radônio/efeitos adversos , Atenção/efeitos da radiação , Atenção/fisiologia , Exposição Ambiental/efeitos adversos , Encéfalo/efeitos da radiação , Ondas Encefálicas/efeitos da radiação , Ondas Encefálicas/fisiologia , Ondas Encefálicas/efeitos dos fármacos , Orientação/fisiologia
16.
Neuroimage ; 288: 120523, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38278427

RESUMO

Although manganese (Mn) is a trace metal essential for humans, chronic exposure to Mn can cause accumulation of this metal ion in the brain leading to an increased risk of neurological and neurobehavioral health effects. This is a concern for welders exposed to Mn through welding fumes. While brain Mn accumulation in occupational settings has mostly been reported in the basal ganglia, several imaging studies also revealed elevated Mn in other brain areas. Since Mn functions as a magnetic resonance imaging (MRI) T1 contrast agent, we developed a whole-brain MRI approach to map in vivo Mn deposition differences in the brains of non-exposed factory controls and exposed welders. This is a cross-sectional analysis of 23 non-exposed factory controls and 36 exposed full-time welders from the same truck manufacturer. We collected high-resolution 3D MRIs of brain anatomy and R1 relaxation maps to identify regional differences using voxel-based quantification (VBQ) and statistical parametric mapping. Furthermore, we investigated the associations between excess Mn deposition and neuropsychological and motor test performance. Our results indicate that: (1) Using whole-brain MRI relaxometry methods we can generate excess Mn deposition maps in vivo, (2) excess Mn accumulation due to occupational exposure occurs beyond the basal ganglia in cortical areas associated with motor and cognitive functions, (3) Mn likely diffuses along white matter tracts in the brain, and (4) Mn deposition in specific brain regions is associated with exposure (cerebellum and frontal cortex) and motor metrics (cerebellum and hippocampus).


Assuntos
Manganês , Ferreiros , Humanos , Estudos Transversais , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Mapeamento Encefálico
17.
J Neurochem ; 168(4): 355-369, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37429600

RESUMO

This review presents recent studies of the chemical and molecular regulators of acetylcholine (ACh) signaling and the complexity of the small molecule and RNA regulators of those mechanisms that control cholinergic functioning in health and disease. The underlying structural, neurochemical, and transcriptomic concepts, including basic and translational research and clinical studies, shed new light on how these processes inter-change under acute states, age, sex, and COVID-19 infection; all of which modulate ACh-mediated processes and inflammation in women and men and under diverse stresses. The aspect of organophosphorus (OP) compound toxicity is discussed based on the view that despite numerous studies, acetylcholinesterase (AChE) is still a vulnerable target in OP poisoning because of a lack of efficient treatment and the limitations of oxime-assisted reactivation of inhibited AChE. The over-arching purpose of this review is thus to discuss mechanisms of cholinergic signaling dysfunction caused by OP pesticides, OP nerve agents, and anti-cholinergic medications; and to highlight new therapeutic strategies to combat both the acute and chronic effects of these chemicals on the cholinergic and neuroimmune systems. Furthermore, OP toxicity was examined in view of cholinesterase inhibition and beyond in order to highlight improved small molecules and RNA therapeutic strategies and assess their predicted pitfalls to reverse the acute toxicity and long-term deleterious effects of OPs.


Assuntos
Reativadores da Colinesterase , Feminino , Humanos , Reativadores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Acetilcolinesterase/química , Compostos Organofosforados , Oximas/química , Oximas/farmacologia , Oximas/uso terapêutico , Acetilcolina , RNA
18.
J Neurochem ; 168(9): 2092-2104, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38344837

RESUMO

Autism spectrum disorder (ASD) is characterized by repetitive behaviors and deficits in social interaction. Its etiology is not completely clear, but both genetic and environmental factors contribute to and influence its development and course. The increased number of autism cases in recent years has been strongly associated with increased exposure to heavy metals. Mercury (Hg) has gained prominence in the scientific literature as a result of its presence as an urban pollutant and well-described neurotoxicity. This review assessed the relationship between Hg exposure in the pre- and post-natal period and ASD. The systematic review identified observational clinical studies and pre-clinical trials in journals indexed in the PubMed, Embase, ProQuest, and LILACS databases. The aim of this study was to investigate the association between exposure to Hg and ASD and to define the critical period of exposure. A total of 57 articles were selected for this review, with 35 articles (61.40%) identifying a positive association between ASD and Hg, while 22 articles (38.60%) did not find the same outcome. The biological samples most used to analyze Hg body burdens were hair (36.84%) and blood (36.84%). Most case-control studies found an increase in Hg levels in individuals with ASD who were exposed to a polluted environment in the post-natal period. Taken together, the studies suggest that these patients have a deficient detoxification system, and this could worsen the symptoms of the disorder. However, new studies addressing the influence of Hg on the post-natal nervous system and its relationship with ASD should be carried out.


Assuntos
Transtorno do Espectro Autista , Mercúrio , Feminino , Humanos , Gravidez , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/induzido quimicamente , Exposição Ambiental/efeitos adversos , Mercúrio/toxicidade
19.
J Neurochem ; 168(6): 1080-1096, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38317263

RESUMO

Sevoflurane, the predominant pediatric anesthetic, has been linked to neurotoxicity in young mice, although the underlying mechanisms remain unclear. This study focuses on investigating the impact of neonatal sevoflurane exposure on cell-type-specific alterations in the prefrontal cortex (PFC) of young mice. Neonatal mice were subjected to either control treatment (60% oxygen balanced with nitrogen) or sevoflurane anesthesia (3% sevoflurane in 60% oxygen balanced with nitrogen) for 2 hours on postnatal days (PNDs) 6, 8, and 10. Behavioral tests and single-nucleus RNA sequencing (snRNA-seq) of the PFC were conducted from PNDs 31 to 37. Mechanistic exploration included clustering analysis, identification of differentially expressed genes (DEGs), enrichment analyses, single-cell trajectory analysis, and genome-wide association studies (GWAS). Sevoflurane anesthesia resulted in sociability and cognition impairments in mice. Novel specific marker genes identified 8 distinct cell types in the PFC. Most DEGs between the control and sevoflurane groups were unique to specific cell types. Re-defining 15 glutamatergic neuron subclusters based on layer identity revealed their altered expression profiles. Notably, sevoflurane disrupted the trajectory from oligodendrocyte precursor cells (OPCs) to oligodendrocytes (OLs). Validation of disease-relevant candidate genes across the main cell types demonstrated their association with social dysfunction and working memory impairment. Behavioral results and snRNA-seq collectively elucidated the cellular atlas in the PFC of young male mice, providing a foundation for further mechanistic studies on developmental neurotoxicity induced by anesthesia.


Assuntos
Anestésicos Inalatórios , Córtex Pré-Frontal , Sevoflurano , Animais , Sevoflurano/toxicidade , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Camundongos , Anestésicos Inalatórios/toxicidade , Masculino , Animais Recém-Nascidos , Feminino , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Estudo de Associação Genômica Ampla
20.
Cancer ; 130(15): 2660-2669, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38578977

RESUMO

BACKGROUND: Tocilizumab is commonly used for the management of chimeric antigen receptor (CAR) T-cell therapy-associated cytokine release syndrome (CRS). However, it remains unknown whether tocilizumab or its dosage affects the efficacy and safety of CAR T-cell therapy. The objective of this multicenter retrospective study was to explore the impact of tocilizumab on CAR T-cell therapy. METHODS: In total, 93 patients with B-cell acute lymphoblastic leukemia (B-ALL) receiving humanized anti-CD19 CAR T cells were recruited from May 2016 to November 2022. Forty-five patients received tocilizumab (tocilizumab group), whereas 48 patients did not (nontocilizumab group). Thirteen patients received >1 dose of tocilizumab. The primary end point was the effect of tocilizumab on the efficacy and safety of CAR T cells. Additionally, proliferation, killing, and cytokine assays of CAR T cells were performed in vitro in the presence of tocilizumab. RESULTS: The median age of the patients was 33 years, with 47 males and 46 females. Patients in the tocilizumab group showed similar complete response (CR) rate, overall survival (OS), and event-free survival (EFS) compared with the nontocilizumab group. Compared with patients who received ≤1 dose of tocilizumab, receiving >1 dose of tocilizumab did not affect their CR rate, OS, or EFS. In the tocilizumab group, all patients experienced CRS and 26.7% experienced immune effector cell-associated neurotoxicity syndrome (ICANS). In the nontocilizumab group, 64.6% of patients experienced CRS and 8.3% experienced ICANS. Up to 75% of ICANS and 87.5% of grade ≥3 ICANS occurred in the tocilizumab group. In vitro, tocilizumab did not impair the proliferation and killing effects of CAR T cells. CONCLUSIONS: Tocilizumab does not affect the efficacy of CAR T cells but may increase the likelihood of ICANS.


Assuntos
Anticorpos Monoclonais Humanizados , Antígenos CD19 , Síndrome da Liberação de Citocina , Imunoterapia Adotiva , Receptores de Antígenos Quiméricos , Humanos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Masculino , Feminino , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Adulto , Antígenos CD19/imunologia , Estudos Retrospectivos , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Síndrome da Liberação de Citocina/etiologia , Receptores de Antígenos Quiméricos/imunologia , Criança , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA