RESUMEN
Rapid advances in genetics are linking mutations on genes to diseases at an exponential rate, yet characterizing the gene-mutation-cell-behavior relationships essential for precision medicine remains a daunting task. More than 350 mutations on small GTPase BRaf are associated with various tumors, and â¼40 mutations are associated with the neurodevelopmental disorder cardio-facio-cutaneous syndrome (CFC). We developed a fast cost-effective lentivirus-based rapid gene replacement method to interrogate the physiopathology of BRaf and â¼50 disease-linked BRaf mutants, including all CFC-linked mutants. Analysis of simultaneous multiple patch-clamp recordings from 6068 pairs of rat neurons with validation in additional mouse and human neurons and multiple learning tests from 1486 rats identified BRaf as the key missing signaling effector in the common synaptic NMDA-R-CaMKII-SynGap-Ras-BRaf-MEK-ERK transduction cascade. Moreover, the analysis creates the original big data unveiling three general features of BRaf signaling. This study establishes the first efficient procedure that permits large-scale functional analysis of human disease-linked mutations essential for precision medicine.
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Sistema de Señalización de MAP Quinasas/genética , Mutación , Proteínas Proto-Oncogénicas B-raf/genética , Transmisión Sináptica/genética , Animales , Células Cultivadas , Enfermedad/genética , Femenino , Técnicas de Transferencia de Gen , Humanos , Lentivirus/genética , Masculino , Ratones Endogámicos C57BL , Neuronas/fisiología , Ratas Sprague-Dawley , Técnicas de Cultivo de TejidosRESUMEN
Sevoflurane exposure in the neonatal period causes long-term developmental neuropsychological dysfunction, including memory impairment and anxiety-like behaviors. However, the molecular mechanisms underlying such effects have not been fully elucidated. In this study, we investigated the effect of neonatal exposure to sevoflurane on neurobehavioral profiles in adolescent rats, and applied an integrated approach of lipidomics and proteomics to investigate the molecular network implicated in neurobehavioral dysfunction. We found that neonatal exposure to sevoflurane caused cognitive impairment and social behavior deficits in adolescent rats. Lipidomics analyses revealed that sevoflurane significantly remodeled hippocampal lipid metabolism, including lysophatidylcholine (LPC) metabolism, phospholipid carbon chain length and carbon chain saturation. Through a combined proteomics analysis, we found that neonatal exposure to sevoflurane significantly downregulated the expression of lysophosphatidylcholine acyltransferase 1 (LPCAT1), a key enzyme in the regulation of phospholipid metabolism, in the hippocampus of adolescent rats. Importantly, hippocampal LPCAT1 overexpression restored the dysregulated glycerophospholipid (GP) metabolism and alleviated the learning and memory deficits caused by sevoflurane. Collectively, our evidence that neonatal exposure to sevoflurane downregulates LPCAT1 expression and dysregulates GP metabolism in the hippocampus, which may contribute to the neurobehavioral dysfunction in the adolescent rats.
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Anestésicos por Inhalación , Animales , Ratas , Sevoflurano/metabolismo , Sevoflurano/farmacología , Animales Recién Nacidos , Anestésicos por Inhalación/farmacología , Ratas Sprague-Dawley , Aprendizaje por Laberinto , Trastornos de la Memoria/metabolismo , Hipocampo/metabolismo , Fosfolípidos/metabolismoRESUMEN
Clarithromycin (CLA) has been widely used in the treatment of bacterial infection. Research reveals the adverse effects on the central nervous system among patients receiving CLA treatment; whereas, a relevant underlying mechanism remains considerably unclear. According to our research, an integrated lipidomic and transcriptomic analysis was applied to explore the effect of CLA on neurobehavior. CLA treatment caused anxiety-like behaviors dose-dependently during open field as well as elevated plus maze trials on mice. Transcriptomes and LC/MS-MS-based metabolomes were adopted for investigating how CLA affected lipidomic profiling as well as metabolic pathway of the cerebral cortex. CLA exposure greatly disturbed glycerophospholipid metabolism and the carbon chain length of fatty acids. By using whole transcriptome sequencing, we found that CLA significantly downregulated the mRNA expression of CEPT1 and CHPT1, two key enzymes involved in the synthesis of glycerophospholipids, supporting the findings from the lipidomic profiling. Also, CLA causes changes in neuronal morphology and function in vitro, which support the existing findings concerning neurobehavior in vivo. We speculate that altered glycerophospholipid metabolism may be involved in the neurobehavioral effect of CLA. Our findings contribute to understanding the mechanisms of CLA-induced adverse effects on the central nervous system. 1. Clarithromycin treatment caused anxiety-like behavior with dose-dependent response both in the open field and elevated plus maze test in mice; 2. Clarithromycin exposing predominately disturbed the metabolism of glycerophospholipids in the cerebral cortex of mice; 3. Clarithromycin application remarkably attenuated CEPT1 and CHPT1 gene expression, which participate in the last step in the synthesis of glycerophospholipids; 4. The altered glycerophospholipid metabolomics may be involved in the abnormal neurobehavior caused by clarithromycin.
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Claritromicina , Lipidómica , Animales , Ratones , Claritromicina/farmacología , Transcriptoma , Glicerofosfolípidos/metabolismo , Corteza Cerebral/metabolismoRESUMEN
Staphylococcus aureus is a major foodborne pathogen that leads to various diseases due to its biofilm and virulence factors. This study aimed to investigate the inhibitory effect of 2R,3R-dihydromyricetin (DMY), a natural flavonoid compound, on the biofilm formation and virulence of S. aureus, and to explore the mode of action using transcriptomic and proteomic analyses. Microscopic observation revealed that DMY could remarkably inhibit the biofilm formation by S. aureus, leading to a collapse on the biofilm architecture and a decrease in viability of biofilm cell. Moreover, the hemolytic activity of S. aureus was reduced to 32.7% after treatment with subinhibitory concentration of DMY (p < 0.01). Bioinformation analysis based on RNA-sequencing and proteomic profiling revealed that DMY induced 262 differentially expressed genes and 669 differentially expressed proteins (p < 0.05). Many downregulated genes and proteins related to surface proteins were involved in biofilm formation, including clumping factor A (ClfA), iron-regulated surface determinants (IsdA, IsdB, and IsdC), fibrinogen-binding proteins (FnbA, FnbB), and serine protease. Meanwhile, DMY regulated a wide range of genes and proteins enriched in bacterial pathogenesis, cell envelope, amino acid metabolism, purine and pyrimidine metabolism, and pyruvate metabolism. These findings suggest that DMY targets S. aureus through multifarious mechanisms, and especially prompt that interference of surface proteins in cell envelope would lead to attenuation of biofilm and virulence.
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Infecciones Estafilocócicas , Staphylococcus aureus , Humanos , Staphylococcus aureus/genética , Virulencia , Proteómica , Transcriptoma , Biopelículas , Proteínas de la Membrana/genética , Antibacterianos/farmacologíaRESUMEN
BACKGROUND: Protein oxidation during food processing causes changes in the balance of protein-molecular interactions and protein-water interactions, ultimately leading to protein denaturation, which results in the loss of a range of functional properties. Therefore, how to control the oxidative modification of proteins during processing has been the focus of research. RESULTS: In the present study, the intrinsic fluorescence value of the myofibrillar proteins (MP) decreased and the surface hydrophobicity value increased, indicating that the heat treatment caused a significant change in the conformation of the MP. With an increase in heating temperature, protein carbonyl content increased, total sulfhydryl content decreased, and protein secondary structure changed from α-helix to ß-sheet, indicating that protein oxidation and aggregation occurred. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that heat treatment can lead to the degradation of proteins, especially myosin heavy chain, although actin had a certain thermal stability. In total, 733 proteins were identified by proteomics, and the protein oxidation caused by low temperature vacuum heating (LTVH) was determined to be mild oxidation dominated by malondialdehyde and 4-hydroxynonenal by oxidation site division. CONCLUSION: The present study has revealed the effect of LTVH treatment on the protein oxidation modification behavior of sturgeon meat, and explored the effect mechanism of LTVH treatment on the processing quality of sturgeon meat from the perspective of protein oxidation. The results may provide a theoretical basis for the precise processing of aquatic products. © 2023 Society of Chemical Industry.
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Calefacción , Proteínas , Animales , Temperatura , Carbonilación Proteica , Vacio , Peces , Péptidos , Oxidación-ReducciónRESUMEN
The development, persistence and relapse of drug addiction require drug memory that generally develops with drug administration-paired contextual stimuli. Adult hippocampal neurogenesis (AHN) contributes to cocaine memory formation; however, the underlying mechanism remains unclear. Male mice hippocampal expression of Tau was significantly decreased during the cocaine-associated memory formation. Genetic overexpression of four microtubule-binding repeats Tau (4R Tau) in the mice hippocampus disrupted cocaine memory by suppressing AHN. Furthermore, 4R Tau directly interacted with phosphoinositide 3-kinase (PI3K)-p85 and impaired its nuclear translocation and PI3K-AKT signaling, processes required for hippocampal neuron proliferation. Collectively, 4R Tau modulates cocaine memory formation by disrupting AHN, suggesting a novel mechanism underlying cocaine memory formation and provide a new strategy for the treatment of cocaine addiction.SIGNIFICANCE STATEMENT Drug memory that generally develops with drug-paired contextual stimuli and drug administration is critical for the development, persistence and relapse of drug addiction. Previous studies have suggested that adult hippocampal neurogenesis (AHN) plays a role in cocaine memory formation. Here, we showed that Tau was significantly downregulated in the hippocampus in the cocaine memory formation. Tau knock-out (KO) promoted AHN in the hippocampal dentate gyrus (DG), resulting in the enhanced memory formation evoked by cocaine-cue stimuli. In contrast, genetically overexpressed 4R Tau in the hippocampus disrupted cocaine-cue memory by suppressing AHN. In addition, 4R Tau interacted directly with phosphoinositide 3-kinase (PI3K)-p85 and hindered its nuclear translocation, eventually repressing PI3K-AKT signaling, which is essential for hippocampal neuronal proliferation.
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Trastornos Relacionados con Cocaína/metabolismo , Hipocampo/metabolismo , Memoria/fisiología , Neurogénesis/fisiología , Proteínas tau/metabolismo , Animales , Masculino , Ratones , Ratones Endogámicos C57BL , Isoformas de ProteínasRESUMEN
Alzheimer's disease (AD) is a progressive neurodegenerative disease with insidious onset, and the deposition of amyloid-ß (Aß) is believed to be one of the main cause. Fluorescence imaging is a promising technique for this task, but the Aß gold standard probe ThT developed based on this still has shortcomings. The development of a new fluorescent probe to detect Aß plaques is thought to be essential. Herein, a series of red to near-infrared emitting fluorescent probes QNO-ADs with newly quinoxalinone skeleton are designed to detect Aß plaques. They all demonstrate excellent optical properties and high binding affinity (â¼Kd = 20 nM) to Aß aggregates. As the most outstanding candidate, QNO-AD-3 shows significant signal-to-noise (S/N) ratio at the level of in vitro binding studies, and the brilliant fluorescence staining results in favor of grasping the approximate distribution of Aß plaques in the brain slice. In vivo Aß plaques imaging suggests that QNO-AD-3 can cross the BBB and have a long retention time in the brain with low biological toxicity. In addition, the results of docking theoretical calculation also provide some references for the design of Aß probe. Overall, given the high affinity of QNO-AD-3 and the ability to monitor Aß plaques for a long time that is not common now, we believe QNO-AD-3 will be an effective tool for an Aß-related matrix and AD disease research in the future.
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Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Enfermedad de Alzheimer/diagnóstico , Péptidos beta-Amiloides/química , Animales , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Colorantes Fluorescentes/química , Ratones , Ratones Transgénicos , Placa Amiloide/diagnóstico por imagenRESUMEN
Rett syndrome (RTT) is a severe neurodevelopmental disease caused by mutations in the methyl-CpG binding protein 2 (MECP2) gene. Although altered interneuron development and function are clearly demonstrated in RTT mice, a particular mode of inhibition, tonic inhibition, has not been carefully examined. We report here that tonic inhibition is significantly reduced in pyramidal neurons in the CA1 region of the hippocampus in mice where Mecp2 is deleted either in all cells or specifically in astrocytes. Since no change is detected in the level of GABA receptors, such a reduction in tonic inhibition is likely a result of decreased ambient GABA level in the extracellular space. Consistent with this explanation, we observed increased expression of a GABA transporter, GABA transporter 3 (GAT3), in the hippocampus of the Mecp2 KO mice, as well as a corresponding increase of GAT3 current in hippocampal astrocytes. These phenotypes are relevant to RTT because pharmacological blockage of GAT3 can normalize tonic inhibition and intrinsic excitability in CA1 pyramidal neurons, and rescue the phenotype of increased network excitability in acute hippocampal slices from the Mecp2 KO mice. Finally, chronic administration of a GAT3 antagonist improved a composite symptom score and extended lifespan in the Mecp2 KO mice. Only male mice were used in this study. These results not only advance our understanding of RTT etiology by defining a new neuronal phenotype and revealing how it can be influenced by astrocytic alterations, but also reveal potential targets for intervention.SIGNIFICANCE STATEMENT Our study reports a novel phenotype of reduced tonic inhibition in hippocampal CA1 pyramidal neurons in the Rett syndrome mice, reveal a potential mechanism of increased GABA transporter expression/activity in the neighboring astrocytes, describe a disease-relevant consequence in hyperexcitability, and provide preliminary evidence that targeting this phenotype may slow down disease progression in Rett syndrome mice. These results help our understanding of the disease etiology and identify a new therapeutic target for treating Rett syndrome.
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Astrocitos/fisiología , Región CA1 Hipocampal/metabolismo , Inhibición Neural , Células Piramidales/fisiología , Síndrome de Rett/metabolismo , Animales , Astrocitos/metabolismo , Región CA1 Hipocampal/citología , Región CA1 Hipocampal/fisiopatología , Proteínas Transportadoras de GABA en la Membrana Plasmática/metabolismo , Masculino , Proteína 2 de Unión a Metil-CpG/genética , Ratones , Células Piramidales/metabolismo , Receptores de GABA/metabolismo , Síndrome de Rett/genética , Síndrome de Rett/fisiopatología , Ácido gamma-Aminobutírico/metabolismoRESUMEN
Cocaine addiction is a chronic relapsing brain disorder characterized by compulsive drug seeking. Preliminary study suggested that bromodomain-containing protein 4 (BRD4), an epigenetic reader protein, participates in cocaine-induced reward and neuroplasticity. However, the exact role of BRD4 in cocaine addiction, particularly cocaine relapse, remains elusive. In this study, we found that BRD4 phosphorylation in the nucleus accumbens (NAc) was closely related to the maintenance of cocaine reinforcement and relapse in different cocaine exposure paradigms. Cocaine significantly increased the binding of phosphorylated BRD4 (pBRD4) at the promoter of Gria2 and Bdnf genes in the NAc. (+)JQ1, a selective BRD4 inhibitor, markedly reduced the reinforcement and reinstatement of cocaine-seeking behaviors, which was accompanied by the decreased expressions of GRIA2 and BDNF. Furthermore, chromatin immunoprecipitation assay showed that (+)JQ1 clearly attenuated cocaine-enhanced binding of pBRD4 at the promotor of Gria2 and Bdnf genes. Blockade of casein kinase II significantly attenuated BRD4 phosphorylation and cocaine relapse-like behaviors, suggesting the important role of pBRD4 in modulating cocaine effect. Together, our findings suggest that BRD4 phosphorylation in the NAc modulates multiple addiction-related behaviors of cocaine and particularly relapse to cocaine-seeking behaviors. Inhibition of BRD4 activity may be a novel target against cocaine addiction and relapse.
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Trastornos Relacionados con Cocaína/genética , Cocaína/farmacología , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Núcleo Accumbens/efectos de los fármacos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Animales , Condicionamiento Operante , Modelos Animales de Enfermedad , Inhibidores de Captación de Dopamina/farmacología , Comportamiento de Búsqueda de Drogas/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Fosforilación , Recurrencia , AutoadministraciónRESUMEN
Rett syndrome (RTT) is a debilitating neurodevelopmental disorder caused by mutations in the MECP2 gene. To facilitate the study of cellular mechanisms in human cells, we established several human stem cell lines: human embryonic stem cell (hESC) line carrying the common T158M mutation (MECP2T158M/T158M ), hESC line expressing no MECP2 (MECP2-KO), congenic pair of wild-type and mutant RTT patient-specific induced pluripotent stem cell (iPSC) line carrying the V247fs mutation (V247fs-WT and V247fs-MT), and iPSC line in which the V247fs mutation was corrected by CRISPR/Cas9-based genome editing (V247fs-MT-correction). Detailed analyses of forebrain neurons differentiated from these human stem cell lines revealed genotype-dependent quantitative phenotypes in neurite growth, dendritic complexity, and mitochondrial function. At the molecular level, we found a significant reduction in the level of CREB and phosphorylated CREB in forebrain neurons differentiated from MECP2T158M/T158M , MECP2-KO, and V247fs-MT stem cell lines. Importantly, overexpression of CREB or pharmacological activation of CREB signaling in those forebrain neurons rescued the phenotypes in neurite growth, dendritic complexity, and mitochondrial function. Finally, pharmacological activation of CREB in the female Mecp2 heterozygous mice rescued several behavioral defects. Together, our study establishes a robust in vitro platform for consistent quantitative evaluation of genotype-dependent RTT phenotypes, reveals a previously unappreciated role of CREB signaling in RTT pathogenesis, and identifies a potential therapeutic target for RTT.SIGNIFICANCE STATEMENT Our study establishes a robust human stem cell-based platform for consistent quantitative evaluation of genotype-dependent Rett syndrome (RTT) phenotypes at the cellular level. By providing the first evidence that enhancing cAMP response element binding protein signaling can alleviate RTT phenotypes both in vitro and in vivo, we reveal a previously unappreciated role of cAMP response element binding protein signaling in RTT pathogenesis, and identify a potential therapeutic target for RTT.
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Proteína de Unión a CREB/metabolismo , Células-Madre Neurales/metabolismo , Células-Madre Neurales/patología , Síndrome de Rett/metabolismo , Síndrome de Rett/patología , Animales , Línea Celular , Progresión de la Enfermedad , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Síndrome de Rett/etiología , Transducción de SeñalRESUMEN
BACKGROUND: The nucleus accumbens in the midbrain dopamine limbic system plays a key role in cocaine addiction. Toll-like receptors (TLRs) are important pattern-recognition receptors (PPRs) in the innate immune system that are also involved in drug dependence; however, the detailed mechanism is largely unknown. METHODS: The present study was designed to investigate the potential role of TLR3 in cocaine addiction. Cocaine-induced conditioned place preference (CPP), locomotor activity, and self-administration were used to determine the effects of TLR3 in the rewarding properties of cocaine. Lentivirus-mediated re-expression of Tlr3 (LV-TLR3) was applied to determine if restoration of TLR3 expression in the NAc is sufficient to restore the cocaine effect in TLR3-/- mice. The protein levels of phospho-NF-κB p65, IKKß, and p-IκBα both in the cytoplasm and nucleus of cocaine-induced CPP mice were detected by Western blot. RESULTS: We showed that both TLR3 deficiency and intra-NAc injection of TLR3 inhibitors significantly attenuated cocaine-induced CPP, locomotor activity, and self-administration in mice. Importantly, the TLR3-/- mice that received intra-NAc injection of LV-TLR3 displayed significant increases in cocaine-induced CPP and locomotor activity. Finally, we found that TLR3 inhibitor reverted cocaine-induced upregulation of phospho-NF-κB p65, IKKß, and p-IκBα. CONCLUSIONS: Taken together, our results describe that TLR3 modulates cocaine-induced behaviors and provide further evidence supporting a role for central pro-inflammatory immune signaling in drug reward. We propose that TLR3 blockade could be a novel approach to treat cocaine addiction.
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Cocaína/farmacología , Condicionamiento Operante/efectos de los fármacos , Inhibidores de Captación de Dopamina/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Receptor Toll-Like 3/metabolismo , Animales , Condicionamiento Operante/fisiología , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica/genética , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Quinasa I-kappa B/metabolismo , Locomoción/efectos de los fármacos , Locomoción/genética , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Inhibidor NF-kappaB alfa , Núcleo Accumbens/efectos de los fármacos , Núcleo Accumbens/metabolismo , Recompensa , Autoadministración , Receptor Toll-Like 3/genética , Factor de Transcripción ReIA , Transducción GenéticaRESUMEN
Recent evidence suggests that histone modifications play a role in the behavioral effects of cocaine in rodent models. Histone arginine is known to be methylated by protein arginine N-methyltransferases (PRMTs). Evidence shows that PRMT1 contributes to >90% of cellular PRMT activity, which regulates histone H4 arginine 3 asymmetric dimethylation (H4R3me2a). Though histone arginine methylation represents a chemical modification that is relatively stable compared with other histone alterations, it is less well studied in the setting of addiction. Here, we demonstrate that repeated noncontingent cocaine injections increase PRMT1 activity in the nucleus accumbens (NAc) of C57BL/6 mice. We, subsequently, identify a selective inhibitor of PRMT1, SKLB-639, and show that systemic injections of the drug decrease cocaine-induced conditioned place preference to levels observed with genetic knockdown of PRMT1. NAc-specific downregulation of PRMT1 leads to hypomethylation of H4R3me2a, and hypoacetylation of histone H3 lysine 9 and 14. We also found that H4R3me2a is upregulated in NAc after repeated cocaine administration, and that H4R3me2a upregulation in turn controls the expression of Cdk5 and CaMKII. Additionally, the suppression of PRMT1 in NAc with lentiviral-short hairpin PMRT1 decreases levels of CaMKII and Cdk5 in the cocaine-treated group, demonstrating that PRMT1 affects the ability of cocaine to induce CaMKII and Cdk5 in NAc. Notably, increased H4R3me2a by repeated cocaine injections is relatively long-lived, as increased expression was observed for up to 7 d after the last cocaine injection. These results show the role of PRMT1 in the behavioral effects of cocaine. SIGNIFICANCE STATEMENT: This work demonstrated that repeated cocaine injections led to an increase of protein arginine N-methyltransferase (PRMT1) in nucleus accumbens (NAc). We then identified a selective inhibitor of PRMT1 (SKLB-639), which inhibited cocaine-induced conditioned place preference (CPP). Additionally, genetic downregulation of PRMT1 in NAc also attenuated cocaine-caused CPP and locomotion activity, which was associated with decreased expression of histone H4 arginine 3 asymmetric demethylation (H4R3me2a) and hypoacetylation of histone H3 lysine 9 and 14 (acH3K9/K14). This study also showed that H4R3me2a controlled transcriptions of Cdk5 and CaMKII, and that PRMT1 negatively affected the ability of cocaine to induce CaMKII and Cdk5 in NAc. Notably, increased H4R3me2a by repeated cocaine injection was relatively long-lived as increased expression was observed up to 7 d after withdrawal from cocaine. Together, this study suggests that PRMT1 inhibition may serve as a potential therapeutic strategy for cocaine addiction.
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Amidinas/farmacología , Cocaína/farmacología , Histonas/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Núcleo Accumbens/enzimología , Procesamiento Proteico-Postraduccional , Proteína-Arginina N-Metiltransferasas/fisiología , Pirimidinas/farmacología , Animales , Ensamble y Desensamble de Cromatina/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Metilación , Ratones , Modelos Moleculares , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Núcleo Accumbens/efectos de los fármacos , Núcleo Accumbens/fisiología , Conformación Proteica , Proteína-Arginina N-Metiltransferasas/antagonistas & inhibidores , Interferencia de ARN , ARN Interferente Pequeño/farmacologíaRESUMEN
Studies have showed that prenatal cocaine exposure (PCOC) can impair cognitive function and social behavior of the offspring; however, the mechanism underlying such effect is poorly understood. Insulin-like growth factor II (Igf-II), an imprinted gene, has a critical role in memory consolidation and enhancement. We hypothesized that epigenetic regulation of hippocampal Igf-II may attribute to the cognitive deficits of PCOC offspring. We used Morris water maze and open-field task to test the cognitive function in PCOC offspring. The epigenetic alteration involved in hippocampal Igf-II expression deficit in PCOC offspring was studied by determining Igf-II methylation status, DNA methyltransferases (DNMT) expressions and L-methionine level. Moreover, IGF-II rescue experiments were performed and the downstream signalings were investigated in PCOC offspring. In behavioral tests, we observed impaired spatial learning and memory and increased anxiety in PCOC offspring; moreover, hippocampal IGF-II mRNA and protein expressions were significantly decreased. Hippocampal methylation of cytosine-phospho-guanine (CpG) dinucleotides in differentially methylated region (DMR) 2 of Igf-II was elevated in PCOC offspring, which may be driven by the upregulation of L-methionine and DNA methyltransferase (DNMT) 1. Importantly, intra-hippocampal injection of recombinant IGF-II reactivated the repressed calcium calmodulin kinase II α (CaMKIIα) and reversed cognitive deficits in PCOC offspring. Collectively, our findings suggest that cocaine exposure during pregnancy impairs cognitive function of offspring through epigenetic modification of Igf-II gene. Enhancing IGF-II signaling may represent a novel therapeutical strategy for cocaine-induced cognitive impairment.
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Cocaína/farmacología , Cognición/efectos de los fármacos , Epigénesis Genética , Factor II del Crecimiento Similar a la Insulina/genética , Efectos Tardíos de la Exposición Prenatal/genética , Animales , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Cognición/fisiología , Metilación de ADN/efectos de los fármacos , Femenino , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Factor II del Crecimiento Similar a la Insulina/metabolismo , Factor II del Crecimiento Similar a la Insulina/farmacología , Aprendizaje por Laberinto/efectos de los fármacos , Aprendizaje por Laberinto/fisiología , Ratones , Fosforilación , Embarazo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Efectos Tardíos de la Exposición Prenatal/psicologíaRESUMEN
BACKGROUND: Nicotine is rapidly absorbed from cigarette smoke and therefore induces a number of chronic illnesses with the widespread use of tobacco products. Studies have shown a few cerebral metabolites modified by nicotine; however, endogenous metabolic profiling in brain has not been well explored. RESULTS: H NMR-based on metabonomics was applied to investigate the endogenous metabolic profiling of brain hippocampus, nucleus acumens (NAc), prefrontal cortex (PFC) and striatum. We found that nicotine significantly increased CPP in mice, and some specific cerebral metabolites differentially changed in nicotine-treated mice. These modified metabolites included glutamate, acetylcholine, tryptamine, glucose, lactate, creatine, 3-hydroxybutyrate and nicotinamide-adenine dinucleotide (NAD), which was closely associated with neurotransmitter and energy source. Additionally, glutathione and taurine in hippocampus and striatum, phosphocholine in PFC and glycerol in NAc were significantly modified by nicotine, implying the dysregulation of anti-oxidative stress response and membrane metabolism. CONCLUSIONS: Nicotine induces significant metabonomic alterations in brain, which are involved in neurotransmitter disturbance, energy metabolism dysregulation, anti-oxidation and membrane function disruptions, as well as amino acid metabolism imbalance. These findings provide a new insight into rewarding effects of nicotine and the underlying mechanism.
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Encéfalo/metabolismo , Espectroscopía de Resonancia Magnética/métodos , Metaboloma/fisiología , Neurotransmisores/metabolismo , Nicotina/farmacología , Animales , Encéfalo/efectos de los fármacos , Masculino , Metaboloma/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Agonistas Nicotínicos/farmacología , ProtonesRESUMEN
Cigarette smoking is known to have negative effects on tissue repair and healing. The aim of this study is to investigate the effects of nicotine in human umbilical cord mesenchymal stem cells (MSCs). After nicotine treatment, MSCs became pyknotic, vacuoles appeared in the cytoplasm and nucleus, and the nuclear boundary became fuzzy as observed using atomic force microscopy. Cell proliferation was inhibited in a dose-dependent manner (P < 0.05 for all concentrations). The proportion of apoptotic MSCs was significantly increased in a dose-dependent manner. The mitochondrial membrane potential was significantly decreased (P < 0.05). Nicotine-treated MSCs had a significantly higher G0/G1 ratio (P < 0.05). Peptide mass fingerprinting identified 27 proteins that were differentially expressed between MSCs with and without nicotine treatment. These nicotine exerted toxic effects on MSCs are likely related, at least in part, to the altered expression of multiple proteins that are essential to the health and proliferation of these cells.
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Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Madre Mesenquimatosas/fisiología , Nicotina/toxicidad , Apoptosis/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Regulación hacia Abajo/efectos de los fármacos , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Células Madre Mesenquimatosas/efectos de los fármacos , Proteoma/metabolismo , Cordón Umbilical/citologíaRESUMEN
Cadmium (Cd) is a pervasive environmental pollutant. Increasing evidence suggests that Cd exposure during pregnancy can induce adverse neurodevelopmental outcomes. However, due to the limitations of neural cell and animal models, it is challenging to study the developmental neurotoxicity and underlying toxicity mechanism of long-term exposure to environmental pollutants during human brain development. In this study, chronic Cd exposure was performed in human mature cerebral organoids for 49 or 77 days. Our study found that prolonged exposure to Cd resulted in the inhibition of cerebral organoid growth and the disruption of neural differentiation and cortical layer organization. These potential consequences of chronic Cd exposure may include impaired GFAP expression, a reduction in SOX2+ neuronal progenitor cells, an increase in TUJ1+ immature neurons, as well as an initial increase and a subsequent decrease in both TBR2+ intermediate progenitors and CTIP2+ deep layer cortical neurons. Transcriptomic analyses revealed that long-term exposure to Cd disrupted zinc and copper ion homeostasis through excessive synthesis of metallothionein and disturbed synaptogenesis, as evidenced by inhibited postsynaptic protein. Our study employed mature cerebral organoids to evaluate the developmental neurotoxicity induced by long-term Cd exposure.
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Contaminantes Ambientales , Células-Madre Neurales , Embarazo , Animales , Femenino , Humanos , Cadmio/metabolismo , Neuronas , Zinc/metabolismo , Contaminantes Ambientales/toxicidad , Contaminantes Ambientales/metabolismo , Organoides/metabolismoRESUMEN
The Bin/Amphiphysin/Rvs (BAR) domain protein FAM92A1 is a multifunctional protein engaged in regulating mitochondrial ultrastructure and ciliogenesis, but its physiological role in the brain remains unclear. Here, we show that FAM92A1 is expressed in neurons starting from embryonic development. FAM92A1 knockout in mice results in altered brain morphology and age-associated cognitive deficits, potentially due to neuronal degeneration and disrupted synaptic plasticity. Specifically, FAM92A1 deficiency impairs diverse neuronal membrane morphology, including the mitochondrial inner membrane, myelin sheath, and synapses, indicating its roles in membrane remodeling and maintenance. By determining the crystal structure of the FAM92A1 BAR domain, combined with atomistic molecular dynamics simulations, we uncover that FAM92A1 interacts with phosphoinositide- and cardiolipin-containing membranes to induce lipid-clustering and membrane curvature. Altogether, these findings reveal the physiological role of FAM92A1 in the brain, highlighting its impact on synaptic plasticity and neural function through the regulation of membrane remodeling and endocytic processes.
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Encéfalo , Cognición , Ratones Noqueados , Plasticidad Neuronal , Neuronas , Sinapsis , Animales , Encéfalo/metabolismo , Neuronas/metabolismo , Sinapsis/metabolismo , Plasticidad Neuronal/fisiología , Ratones , Cognición/fisiología , Membrana Celular/metabolismo , Simulación de Dinámica Molecular , Humanos , Fosfatidilinositoles/metabolismo , Cardiolipinas/metabolismo , MasculinoRESUMEN
BACKGROUND: Circular RNAs are highly enriched in the synapses of the mammalian brain and play important roles in neurological function by acting as molecular sponges of microRNAs. circAnk3 is derived from the 11th intron of the ankyrin-3 gene, Ank3, a strong genetic risk factor for neuropsychiatric disorders; however, the function of circAnk3 remains elusive. In this study, we investigated the function of circAnk3 and its downstream regulatory network for target genes in the hippocampus of mice. METHODS: The DNA sequence from which circAnk3 is generated was modified using CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/Cas9) technology, and neurobehavioral tests (anxiety and depression-like behaviors, social behaviors) were performed in circAnk3+/- mice. A series of molecular and biochemical assays were used to investigate the function of circAnk3 as a microRNA sponge and its downstream regulatory network for target genes. RESULTS: circAnk3+/- mice exhibited both anxiety-like behaviors and social deficits. circAnk3 was predominantly located in the cytoplasm of neuronal cells and functioned as a miR-7080-3p sponge to regulate the expression of Iqgap1. Inhibition of miR-7080-3p or restoration of Iqgap1 in the hippocampus ameliorated the behavioral deficits of circAnk3+/- mice. Furthermore, circAnk3 deficiency decreased the expression of the NMDA receptor subunit GluN2a and impaired the structural plasticity of dendritic synapses in the hippocampus. CONCLUSIONS: Our results reveal an important role of the circAnk3/miR-7080-3p/IQGAP1 axis in maintaining the structural plasticity of hippocampal synapses. circAnk3 might offer new insights into the involvement of circular RNAs in neuropsychiatric disorders.
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MicroARNs , ARN Circular , Ratones , Animales , ARN Circular/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Hipocampo/metabolismo , Encéfalo/metabolismo , Ansiedad/genética , Mamíferos/genética , Mamíferos/metabolismoRESUMEN
Neuronal activation is required for the formation of drug-associated memory, which is critical for the development, persistence, and relapse of drug addiction. Nevertheless, the metabolic mechanisms underlying energy production for neuronal activation remain poorly understood. In the study, a large-scale proteomics analysis of lysine crotonylation (Kcr), a type of protein posttranslational modification (PTM), reveals that cocaine promoted protein Kcr in the hippocampal dorsal dentate gyrus (dDG). We find that Kcr is predominantly discovered in a few enzymes critical for mitochondrial energy metabolism; in particular, pyruvate dehydrogenase (PDH) complex E1 subunit α (PDHA1) is crotonylated at the lysine 39 (K39) residue through P300 catalysis. Crotonylated PDHA1 promotes pyruvate metabolism by activating PDH to increase ATP production, thus providing energy for hippocampal neuronal activation and promoting cocaine-associated memory recall. Our findings identify Kcr of PDHA1 as a PTM that promotes pyruvate metabolism to enhance neuronal activity for cocaine-associated memory.