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2.
Transl Psychiatry ; 13(1): 243, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37407615

RESUMO

The anterior cingulate cortex (ACC) has been implicated in attention deficit hyperactivity disorder (ADHD). More specifically, an appropriate balance of excitatory and inhibitory activity in the ACC may be critical for the control of impulsivity, hyperactivity, and sustained attention which are centrally affected in ADHD. Hence, pharmacological augmentation of parvalbumin- (PV) or somatostatin-positive (Sst) inhibitory ACC interneurons could be a potential treatment strategy. We, therefore, tested whether stimulation of Gq-protein-coupled receptors (GqPCRs) in these interneurons could improve attention or impulsivity assessed with the 5-choice-serial reaction-time task in male mice. When challenging impulse control behaviourally or pharmacologically, activation of the chemogenetic GqPCR hM3Dq in ACC PV-cells caused a selective decrease of active erroneous-i.e. incorrect and premature-responses, indicating improved attentional and impulse control. When challenging attention, in contrast, omissions were increased, albeit without extension of reward latencies or decreases of attentional accuracy. These effects largely resembled those of the ADHD medication atomoxetine. Additionally, they were mostly independent of each other within individual animals. GqPCR activation in ACC PV-cells also reduced hyperactivity. In contrast, if hM3Dq was activated in Sst-interneurons, no improvement of impulse control was observed, and a reduction of incorrect responses was only induced at high agonist levels and accompanied by reduced motivational drive. These results suggest that the activation of GqPCRs expressed specifically in PV-cells of the ACC may be a viable strategy to improve certain aspects of sustained attention, impulsivity and hyperactivity in ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Giro do Cíngulo , Masculino , Camundongos , Animais , Parvalbuminas , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Agitação Psicomotora , Comportamento Impulsivo , Interneurônios
3.
Sci Adv ; 9(30): eabo7622, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37506209

RESUMO

Hypertrophic cardiomyopathy (HCM) is a primary myocardial disorder characterized by left ventricular hypertrophy, hyperdynamic contraction, and impaired relaxation of the heart. These functional derangements arise directly from altered sarcomeric function due to either mutations in genes encoding sarcomere proteins, or other defects such as abnormal energetics. Current treatment options do not directly address this causal biology but focus on surgical and extra-sarcomeric (sarcolemmal) pharmacological symptomatic relief. Mavacamten (formerly known as MYK-461), is a small molecule designed to regulate cardiac function at the sarcomere level by selectively but reversibly inhibiting the enzymatic activity of myosin, the fundamental motor of the sarcomere. This review summarizes the mechanism and translational progress of mavacamten from proteins to patients, describing how the mechanism of action and pharmacological characteristics, involving both systolic and diastolic effects, can directly target pathophysiological derangements within the cardiac sarcomere to improve cardiac structure and function in HCM. Mavacamten was approved by the Food and Drug Administration in April 2022 for the treatment of obstructive HCM and now goes by the commercial name of Camzyos. Full information about the risks, limitations, and side effects can be found at www.accessdata.fda.gov/drugsatfda_docs/label/2022/214998s000lbl.pdf.


Assuntos
Cardiomiopatia Hipertrófica , Medicina de Precisão , Estados Unidos , Humanos , Cardiomiopatia Hipertrófica/tratamento farmacológico , Cardiomiopatia Hipertrófica/genética , Benzilaminas/efeitos adversos , Benzilaminas/química , Miosinas
4.
HardwareX ; 14: e00429, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37250189

RESUMO

In vivo electro- and optophysiology experiments in rodents reveal the neural mechanisms underlying behavior and brain disorders but mostly involve a cable connection between an implant in the animal and an external recording device. Standard tethers with thin cables or non-motorized commutators require constant monitoring and often manual interference to untwist the cable. Motorized commutators offer a solution, but those few that are commercially available are expensive and often not adapted to widely used connector standards of the open-source community like 12-channel SPI. Here we introduce an open-source motorized all-in-one commutator (Open-MAC): a low-cost (240-390 EUR), low-torque motorized commutator that can operate with minimal audible noise in a torque-based mode relying on dual magnetic Hall sensors. It further includes electronics to operate in a torque-free, online pose-estimation-based mode, with future developments. Operation is controlled by an onboard microcontroller (XIAO SAMD21) powered by a USB-C cable or DC power supply. The body and movable parts are 3D-printed. Different Open-MAC versions can support electrophysiology with up to 64 recording channels using the Open-Ephys / IntanTM recording systems as well as miniature endoscope (miniscope) recordings using the UCLA Miniscope v3/4, and can host a fibre for optogenetic modulation.

5.
Nat Commun ; 14(1): 3150, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37258521

RESUMO

How the genetic landscape governs a tumor's response to immunotherapy remains poorly understood. To assess the immune-modulatory capabilities of 573 genes associated with altered cytotoxicity in human cancers, here we perform CRISPR/Cas9 screens directly in mouse lung cancer models. We recover the known immune evasion factors Stat1 and Serpinb9 and identify the cancer testis antigen Adam2 as an immune modulator, whose expression is induced by KrasG12D and further elevated by immunotherapy. Using loss- and gain-of-function experiments, we show that ADAM2 functions as an oncogene by restraining interferon and TNF cytokine signaling causing reduced presentation of tumor-associated antigens. ADAM2 also restricts expression of the immune checkpoint inhibitors PDL1, LAG3, TIGIT and TIM3 in the tumor microenvironment, which might explain why ex vivo expanded and adoptively transferred cytotoxic T-cells show enhanced cytotoxic efficacy in ADAM2 overexpressing tumors. Together, direct in vivo CRISPR/Cas9 screens can uncover genetic alterations that control responses to immunotherapies.


Assuntos
Antineoplásicos , Fertilinas , Neoplasias Pulmonares , Serpinas , Animais , Humanos , Masculino , Camundongos , Antígenos de Neoplasias , Fertilinas/genética , Imunoterapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Proteínas de Membrana/genética , Serpinas/genética , Linfócitos T Citotóxicos , Microambiente Tumoral
6.
Blood Cancer Discov ; 4(3): 180-207, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36763002

RESUMO

Acute myeloid leukemia (AML) is fueled by leukemic stem cells (LSC) whose determinants are challenging to discern from hematopoietic stem cells (HSC) or uncover by approaches focused on general cell properties. We have identified a set of RNA-binding proteins (RBP) selectively enriched in human AML LSCs. Using an in vivo two-step CRISPR-Cas9 screen to assay stem cell functionality, we found 32 RBPs essential for LSCs in MLL-AF9;NrasG12D AML. Loss-of-function approaches targeting key hit RBP ELAVL1 compromised LSC-driven in vivo leukemic reconstitution, and selectively depleted primitive malignant versus healthy cells. Integrative multiomics revealed differentiation, splicing, and mitochondrial metabolism as key features defining the leukemic ELAVL1-mRNA interactome with mitochondrial import protein, TOMM34, being a direct ELAVL1-stabilized target whose repression impairs AML propagation. Altogether, using a stem cell-adapted in vivo CRISPR screen, this work demonstrates pervasive reliance on RBPs as regulators of LSCs and highlights their potential as therapeutic targets in AML. SIGNIFICANCE: LSC-targeted therapies remain a significant unmet need in AML. We developed a stem-cell-adapted in vivo CRISPR screen to identify key LSC drivers. We uncover widespread RNA-binding protein dependencies in LSCs, including ELAVL1, which we identify as a novel therapeutic vulnerability through its regulation of mitochondrial metabolism. This article is highlighted in the In This Issue feature, p. 171.


Assuntos
Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Diferenciação Celular , Células-Tronco Hematopoéticas/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/uso terapêutico , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Proteína Semelhante a ELAV 1/genética , Proteína Semelhante a ELAV 1/metabolismo
7.
Front Behav Neurosci ; 16: 1002223, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36225391

RESUMO

Schizophrenia is a severe psychiatric disorder whose neurodevelopmental pathogenesis includes a prodromal phase before its diagnostically decisive-namely psychotic-symptoms are present. This prodrome is characterized by cognitive and affective deficits, and it may constitute a critical time period for an early therapeutic intervention to improve or even prevent further disease development. N-acetylcysteine (NAC) is an easily repurposable compound that has recently shown promise in improving non-psychotic symptoms in patients with established schizophrenia. Its therapeutic mechanism may involve the amelioration of circuit abnormalities like a hyper-glutamatergic state and oxidative stress in cortex which have been proposed to drive the pathogenesis of this disease. However, it is currently unknown to what extent NAC can actually improve prodromal aberrations. To investigate this preclinically, we deployed the cyclin-D2 knockout mouse model (CD2-KO) that shares physiological and behavioral abnormalities with the schizophrenia prodrome, including a hyperactive CA1 region, and cognitive and affective deficits. Applying NAC chronically in drinking water (0.9 g/l) during development (∼P22-P70), we found that excessive novelty-induced hyperlocomotion was neither ameliorated during (∼P68) nor after (∼P75) treatment; similarly, T-maze working memory (tested after treatment; ∼P84) was unaffected. However, once chronic NAC treatment was resumed (at approximately P134) in those mice that had received it before, working memory, cognitive flexibility (tested under NAC), and anhedonia (sucrose-preference, tested 1 day after NAC-treatment stopped) were improved in CD2-KO mice. This suggests that chronic NAC treatment may be a therapeutic strategy to improve some cognitive and affective dysfunctions in the schizophrenia prodrome.

8.
Cancer Discov ; 12(12): 2930-2953, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36108220

RESUMO

Systematically investigating the scores of genes mutated in cancer and discerning disease drivers from inconsequential bystanders is a prerequisite for precision medicine but remains challenging. Here, we developed a somatic CRISPR/Cas9 mutagenesis screen to study 215 recurrent "long-tail" breast cancer genes, which revealed epigenetic regulation as a major tumor-suppressive mechanism. We report that components of the BAP1 and COMPASS-like complexes, including KMT2C/D, KDM6A, BAP1, and ASXL1/2 ("EpiDrivers"), cooperate with PIK3CAH1047R to transform mouse and human breast epithelial cells. Mechanistically, we find that activation of PIK3CAH1047R and concomitant EpiDriver loss triggered an alveolar-like lineage conversion of basal mammary epithelial cells and accelerated formation of luminal-like tumors, suggesting a basal origin for luminal tumors. EpiDriver mutations are found in ∼39% of human breast cancers, and ∼50% of ductal carcinoma in situ express casein, suggesting that lineage infidelity and alveogenic mimicry may significantly contribute to early steps of breast cancer etiology. SIGNIFICANCE: Infrequently mutated genes comprise most of the mutational burden in breast tumors but are poorly understood. In vivo CRISPR screening identified functional tumor suppressors that converged on epigenetic regulation. Loss of epigenetic regulators accelerated tumorigenesis and revealed lineage infidelity and aberrant expression of alveogenesis genes as potential early events in tumorigenesis. This article is highlighted in the In This Issue feature, p. 2711.


Assuntos
Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Humanos , Camundongos , Animais , Feminino , Neoplasias da Mama/patologia , Epigênese Genética , Recidiva Local de Neoplasia/genética , Carcinoma Intraductal não Infiltrante/genética , Transformação Celular Neoplásica/genética
9.
Neurochem Res ; 47(6): 1765-1777, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35347633

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder with selective degeneration of motor neurons in the central nervous system. The pathophysiology of ALS is not well understood. We have used 1H-[13C]-NMR spectroscopy together with an administration of [1,6-13C2]glucose and [2-13C]acetate in female and male SOD1G37R mice to assess neuronal and astroglial metabolic activity, respectively, in the central nervous system in ALS condition. The female (p = 0.0008) and male (p < 0.0001) SOD1G37R mice exhibited decreased forelimb strength when compared with wild-type mice. There was a reduction in N-acetylaspartylglutamate level, and elevation in myo-inositol in the spinal cord of female and male SOD1G37R mice. The transgenic male mice exhibited increased acetate oxidation in the spinal cord (p = 0.05) and cerebral cortex (p = 0.03), while females showed an increase in the spinal cord (p = 0.02) only. As acetate is transported and preferentially metabolized in the astrocytes, the finding of increased rate of acetate oxidation in the transgenic mice is suggestive of astrocytic involvement in the pathogenesis of ALS. The rates of glucose oxidation in glutamatergic (p = 0.0004) and GABAergic neurons (p = 0.0052) were increased in the cerebral cortex of male SOD1G37R mice when compared with the controls. The female mice showed an increase in glutamatergic (p = 0.039) neurometabolic activity only. The neurometabolic activity was unperturbed in the spinal cord of either sex. These data suggest differential changes in neurometabolic activity across the central nervous system in SOD1G37R mice.


Assuntos
Esclerose Lateral Amiotrófica , Esclerose Lateral Amiotrófica/metabolismo , Animais , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Feminino , Glucose/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Medula Espinal/metabolismo , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1/metabolismo
10.
Transl Psychiatry ; 12(1): 102, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35288531

RESUMO

Schizophrenia is associated with a broad range of severe and currently pharmacoresistant cognitive deficits. Prior evidence suggests that hypofunction of AMPA-type glutamate receptors (AMPARs) containing the subunit GLUA1, encoded by GRIA1, might be causally related to impairments of selective attention and memory in this disorder, at least in some patients. In order to clarify the roles of GluA1 in distinct cell populations, we investigated behavioural consequences of selective Gria1-knockout in excitatory neurons of subdivisions of the prefrontal cortex and the hippocampus, assessing sustained attention, impulsivity, cognitive flexibility, anxiety, sociability, hyperactivity, and various forms of short-term memory in mice. We found that virally induced reduction of GluA1 across multiple hippocampal subfields impaired spatial working memory. Transgene-mediated ablation of GluA1 from excitatory cells of CA2 impaired short-term memory for conspecifics and objects. Gria1 knockout in CA3 pyramidal cells caused mild impairments of object-related and spatial short-term memory, but appeared to partially increase social interaction and sustained attention and to reduce motor impulsivity. Our data suggest that reduced hippocampal GluA1 expression-as seen in some patients with schizophrenia-may be a central cause particularly for several short-term memory deficits. However, as impulse control and sustained attention actually appeared to improve with GluA1 ablation in CA3, strategies of enhancement of AMPAR signalling likely require a fine balance to be therapeutically effective across the broad symptom spectrum of schizophrenia.


Assuntos
Hipocampo , Receptores de AMPA , Animais , Hipocampo/metabolismo , Humanos , Memória de Curto Prazo/fisiologia , Camundongos , Camundongos Knockout , Receptores de AMPA/genética , Receptores de AMPA/metabolismo , Memória Espacial
12.
Anticancer Agents Med Chem ; 22(2): 313-327, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33845751

RESUMO

BACKGROUND: In the current era, the development of molecular techniques involves nano techniques, and the synthesis of nanoparticles is considered the preferred field in nanotechnology. OBJECTIVE: The aim of the present work is to analyze the anticancer activity of the thymoquinone conjugated ZnO nanoparticles and understand its mechanism of action in triple-negative breast cancer cell lines MDA-MB-231. METHODS: Zinc Oxide (ZnO) nanoparticles have extensive applications, and it was synthesized using a chemical precipitation method. Thymoquinone (TQ) is the major bioactive component of the seeds of Nigella sativa. Synthesized nanoparticles were characterized using various spectroscopic techniques. Thymoquinone-coated nanoparticles were checked for their efficiency. The cytotoxicity of ZnO, TQ, and TQ conjugated ZnO nanoparticles against MDA-MB-231. Colony-forming and cell migration assays were performed to measure the proliferative competence of the breast cancer cells on exposure to nanoparticles. The mechanism of apoptosis was probed by assessing MMP, interplay between ER stress and ROS. RESULTS: The results of the characterization techniques confirmed that the particles synthesized were ZnO and TQ-ZnO nanoparticles. pH dependent release of the compound was observed. The anti-proliferative effect that impairs the formation of the colony was found to be enhanced in cells exposed to combined treatment with the nanoconjugate. CONCLUSION: Hence, the TQ conjugated ZnO nanoparticles can act as an efficient carrier for drug delivery at the target site in TNBC cells.


Assuntos
Antineoplásicos/farmacologia , Benzoquinonas/farmacologia , Nanopartículas/química , Óxido de Zinco/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Benzoquinonas/química , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Óxido de Zinco/química
13.
Sci Rep ; 11(1): 22279, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34782697

RESUMO

Operant boxes enable the application of complex behavioural paradigms to support circuit neuroscience and drug discovery research. However, commercial operant box systems are expensive and often not optimised for combining behaviour with neurophysiology. Here we introduce a fully open-source Python-based operant-box system in a 5-choice design (pyOS-5) that enables assessment of multiple cognitive and affective functions. It is optimized for fast turn-over between animals, and for testing of tethered mice for simultaneous physiological recordings or optogenetic manipulation. For reward delivery, we developed peristaltic and syringe pumps based on a stepper motor and 3D-printed parts. Tasks are specified using a Python-based syntax implemented on custom-designed printed circuit boards that are commercially available at low cost. We developed an open-source graphical user interface (GUI) and task definition scripts to conduct assays assessing operant learning, attention, impulsivity, working memory, or cognitive flexibility, alleviating the need for programming skills of the end user. All behavioural events are recorded with millisecond resolution, and TTL-outputs and -inputs allow straightforward integration with physiological recordings and closed-loop manipulations. This combination of features realizes a cost-effective, nose-poke-based operant box system that allows reliable circuit-neuroscience experiments investigating correlates of cognition and emotion in large cohorts of subjects.


Assuntos
Comportamento Animal , Cognição , Condicionamento Operante , Fenômenos Eletrofisiológicos , Animais , Aprendizagem , Memória , Camundongos , Tempo de Reação , Reprodutibilidade dos Testes , Interface Usuário-Computador
14.
J Mol Biol ; 433(23): 167295, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34627791

RESUMO

In addition to a conventional relaxed state, a fraction of myosins in the cardiac muscle exists in a low-energy consuming super-relaxed (SRX) state, which is kept as a reserve pool that may be engaged under sustained increased cardiac demand. The conventional relaxed and the super-relaxed states are widely assumed to correspond to a structure where myosin heads are in an open configuration, free to interact with actin, and a closed configuration, inhibiting binding to actin, respectively. Disruption of the myosin SRX population is an emerging model in different heart diseases, such as hypertrophic cardiomyopathy, which results in excessive muscle contraction, and stabilizing them using myosin inhibitors is budding as an attractive therapeutic strategy. Here we examined the structure-function relationships of two myosin ATPase inhibitors, mavacamten and para-nitroblebbistatin, and found that binding of mavacamten at a site different than para-nitroblebbistatin populates myosin into the SRX state. Para-nitroblebbistatin, binding to a distal pocket to the myosin lever arm near the nucleotide-binding site, does not affect the usual myosin SRX state but instead appears to render myosin into a new, perhaps much more inhibited, 'ultra-relaxed' state. X-ray scattering-based rigid body modeling shows that both mavacamten and para-nitroblebbistatin induce novel conformations in human ß-cardiac heavy meromyosin that diverge significantly from the hypothetical open and closed states, and furthermore, mavacamten treatment causes greater compaction than para-nitroblebbistatin. Taken together, we conclude that mavacamten and para-nitroblebbistatin stabilize myosin in different structural states, and such states may give rise to different functional energy-sparing states.


Assuntos
Benzilaminas/química , Modelos Moleculares , Conformação Proteica , Uracila/análogos & derivados , Miosinas Ventriculares/química , Benzilaminas/farmacologia , Miosinas/antagonistas & inibidores , Miosinas/química , Domínios e Motivos de Interação entre Proteínas , Estabilidade Proteica , Análise Espectral , Relação Estrutura-Atividade , Uracila/química , Uracila/farmacologia , Miosinas Ventriculares/antagonistas & inibidores
15.
Commun Biol ; 4(1): 662, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34079054

RESUMO

Pathological impulsivity is a debilitating symptom of multiple psychiatric diseases with few effective treatment options. To identify druggable receptors with anti-impulsive action we developed a systematic target discovery approach combining behavioural chemogenetics and gene expression analysis. Spatially restricted inhibition of three subdivisions of the prefrontal cortex of mice revealed that the anterior cingulate cortex (ACC) regulates premature responding, a form of motor impulsivity. Probing three G-protein cascades with designer receptors, we found that the activation of Gi-signalling in layer-5 pyramidal cells (L5-PCs) of the ACC strongly, reproducibly, and selectively decreased challenge-induced impulsivity. Differential gene expression analysis across murine ACC cell-types and 402 GPCRs revealed that - among Gi-coupled receptor-encoding genes - Grm2 is the most selectively expressed in L5-PCs while alternative targets were scarce. Validating our approach, we confirmed that mGluR2 activation reduced premature responding. These results suggest Gi-coupled receptors in ACC L5-PCs as therapeutic targets for impulse control disorders.


Assuntos
Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/fisiologia , Giro do Cíngulo/citologia , Giro do Cíngulo/fisiologia , Células Piramidais/fisiologia , Animais , Clozapina/análogos & derivados , Clozapina/farmacologia , Feminino , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/efeitos dos fármacos , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Expressão Gênica/efeitos dos fármacos , Giro do Cíngulo/efeitos dos fármacos , Humanos , Comportamento Impulsivo/efeitos dos fármacos , Comportamento Impulsivo/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Células Piramidais/citologia , Células Piramidais/efeitos dos fármacos , Receptores de Glutamato Metabotrópico/efeitos dos fármacos , Receptores de Glutamato Metabotrópico/genética , Receptores de Glutamato Metabotrópico/fisiologia , Transdução de Sinais
16.
Sci Rep ; 11(1): 8788, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888809

RESUMO

A hypofunction of N-methyl-D-aspartate glutamate receptors (NMDARs) has been implicated in the pathogenesis of schizophrenia by clinical and rodent studies. However, to what extent NMDAR-hypofunction in distinct cell-types across the brain causes different symptoms of this disease is largely unknown. One pharmaco-resistant core symptom of schizophrenia is impaired working memory (WM). NMDARs have been suggested to mediate sustained firing in excitatory neurons of the prefrontal cortex (PFC) that might underlie WM storage. However, if NMDAR-hypofunction in prefrontal excitatory neurons may indeed entail WM impairments is unknown. We here investigated this question in mice, in which NMDARs were genetically-ablated in PFC excitatory cells. This cell type-selective NMDAR-hypofunction caused a specific deficit in a delayed-matching-to-position (DMTP) 5-choice-based operant WM task. In contrast, T-maze rewarded alternation and several psychological functions including attention, spatial short-term habituation, novelty-processing, motivation, sociability, impulsivity, and hedonic valuation remained unimpaired at the level of GluN1-hypofunction caused by our manipulation. Our data suggest that a hypofunction of NMDARs in prefrontal excitatory neurons may indeed cause WM impairments, but are possibly not accounting for most other deficits in schizophrenia.


Assuntos
Memória de Curto Prazo/fisiologia , Córtex Pré-Frontal/fisiologia , Células Piramidais/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , Animais , Camundongos , Córtex Pré-Frontal/citologia , Receptores de N-Metil-D-Aspartato/genética , Esquizofrenia/fisiopatologia
17.
BMC Biol ; 19(1): 24, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33557811

RESUMO

BACKGROUND: Communication between brain areas has been implicated in a wide range of cognitive and emotive functions and is impaired in numerous mental disorders. In rodent models, various metrics have been used to quantify inter-regional neuronal communication. However, in individual studies, typically, only very few measures of coupling are reported and, hence, redundancy across such indicators is implicitly assumed. RESULTS: In order to test this assumption, we here comparatively assessed a broad range of directional and non-directional metrics like coherence, Weighted Phase Lag Index (wPLI), phase-locking value (PLV), pairwise phase consistency (PPC), parametric and non-parametric Granger causality (GC), partial directed coherence (PDC), directed transfer function (DTF), spike-phase coupling (SPC), cross-regional phase-amplitude coupling, amplitude cross-correlations and others. We applied these analyses to simultaneous field recordings from the prefrontal cortex and the ventral and dorsal hippocampus in the schizophrenia-related Gria1-knockout mouse model which displays a robust novelty-induced hyperconnectivity phenotype. Using the detectability of coupling deficits in Gria1-/- mice and bivariate correlations within animals as criteria, we found that across such measures, there is a considerable lack of functional redundancy. Except for three pairwise correlations-PLV with PPC, PDC with DTF and parametric with non-parametric Granger causality-almost none of the analysed metrics consistently co-varied with any of the other measures across the three connections and two genotypes analysed. Notable exceptions to this were the correlation of coherence with PPC and PLV that was found in most cases, and partial correspondence between these three measures and Granger causality. Perhaps most surprisingly, partial directed coherence and Granger causality-sometimes regarded as equivalent measures of directed influence-diverged profoundly. Also, amplitude cross-correlation, spike-phase coupling and theta-gamma phase-amplitude coupling each yielded distinct results compared to all other metrics. CONCLUSIONS: Our analysis highlights the difficulty of quantifying real correlates of inter-regional information transfer, underscores the need to assess multiple coupling measures and provides some guidelines which metrics to choose for a comprehensive, yet non-redundant characterization of functional connectivity.


Assuntos
Comunicação Celular , Hipocampo/fisiologia , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Fenômenos Eletrofisiológicos , Feminino , Masculino , Camundongos , Camundongos Knockout
18.
J Biol Chem ; 296: 100114, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33234590

RESUMO

A hallmark feature of myosin-II is that it can spontaneously self-assemble into bipolar synthetic thick filaments (STFs) in low-ionic-strength buffers, thereby serving as a reconstituted in vitro model for muscle thick filaments. Although these STFs have been extensively used for structural characterization, their functional evaluation has been limited. In this report, we show that myosins in STFs mirror the more electrostatic and cooperative interactions that underlie the energy-sparing super-relaxed (SRX) state, which are not seen using shorter myosin subfragments, heavy meromyosin (HMM) and myosin subfragment 1 (S1). Using these STFs, we show several pathophysiological insults in hypertrophic cardiomyopathy, including the R403Q myosin mutation, phosphorylation of myosin light chains, and an increased ADP:ATP ratio, destabilize the SRX population. Furthermore, WT myosin containing STFs, but not S1, HMM, or STFs-containing R403Q myosin, recapitulated the ADP-induced destabilization of the SRX state. Studies involving a clinical-stage small-molecule inhibitor, mavacamten, showed that it is more effective in not only increasing myosin SRX population in STFs than in S1 or HMM but also in increasing myosin SRX population equally well in STFs made of healthy and disease-causing R403Q myosin. Importantly, we also found that pathophysiological perturbations such as elevated ADP concentration weakens mavacamten's ability to increase the myosin SRX population, suggesting that mavacamten-bound myosin heads are not permanently protected in the SRX state but can be recruited into action. These findings collectively emphasize that STFs serve as a valuable tool to provide novel insights into the myosin SRX state in healthy, diseased, and therapeutic conditions.


Assuntos
Benzilaminas/química , Benzilaminas/metabolismo , Miosinas/metabolismo , Uracila/análogos & derivados , Trifosfato de Adenosina/metabolismo , Animais , Humanos , Músculo Esquelético/metabolismo , Contração Miocárdica/fisiologia , Cadeias Leves de Miosina/química , Cadeias Leves de Miosina/metabolismo , Subfragmentos de Miosina/química , Subfragmentos de Miosina/metabolismo , Miosinas/química , Fosforilação/fisiologia , Uracila/química , Uracila/metabolismo
19.
Science ; 367(6483): 1264-1269, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32165588

RESUMO

In most human cancers, only a few genes are mutated at high frequencies; most are mutated at low frequencies. The functional consequences of these recurrent but infrequent "long tail" mutations are often unknown. We focused on 484 long tail genes in head and neck squamous cell carcinoma (HNSCC) and used in vivo CRISPR to screen for genes that, upon mutation, trigger tumor development in mice. Of the 15 tumor-suppressor genes identified, ADAM10 and AJUBA suppressed HNSCC in a haploinsufficient manner by promoting NOTCH receptor signaling. ADAM10 and AJUBA mutations or monoallelic loss occur in 28% of human HNSCC cases and are mutually exclusive with NOTCH receptor mutations. Our results show that oncogenic mutations in 67% of human HNSCC cases converge onto the NOTCH signaling pathway, making NOTCH inactivation a hallmark of HNSCC.


Assuntos
Genes Supressores de Tumor , Predisposição Genética para Doença , Neoplasias de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Proteínas Supressoras de Tumor/genética , Proteína ADAM10/genética , Secretases da Proteína Precursora do Amiloide/genética , Animais , Sistemas CRISPR-Cas , Feminino , Testes Genéticos , Células HEK293 , Humanos , Proteínas com Domínio LIM/genética , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Mutação , Receptores Notch/genética , Transdução de Sinais/genética
20.
J Family Med Prim Care ; 9(11): 5554-5558, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33532394

RESUMO

BACKGROUND: It is imperative to acknowledge that COVID-19 poses significant burden on the psychological well-being of people. With implementation of lockdown and measures like quarantine, the mental health of people is affected, and the associated problems may range from depression to suicidal ideation. With this background, the aim of this study was to assess COVID-19 anxiety among general population of the state of Andhra Pradesh. MATERIALS AND METHODS: This cross-sectional study assessed the COVID-19 anxiety among the population of Andhra Pradesh using COVID-19 Anxiety Scale (CAS-7), a seven-item validated psychometric instrument which assesses the cognitive, emotional, and physiological dimensions of COVID-19 anxiety, using a semantic differential scale. The final sample constituted 1,346 participants. Statistical analysis was done using SPSS version 20 software (IBM SPSS statistics for Windows version 20, Armonk, NY, USA). RESULTS: The mean age of the study participants was 36.13 ± 10.2 years, and 55.8% were males. The mean CAS-7 score in this study was found to be 18.9 ± 6.4. The item with highest mean scores was: "How concerned are you when people cough or sneeze because of the fear that you may acquire COVID-19?" No significant differences in CAS-7 scores were found based on gender, educational qualification of the participants, while significant differences were observed based on place of residence, presence of COVID-19 affected individuals in close surroundings, tobacco, and alcohol consumption. CONCLUSION: The results of this study inform that it is imperative for authorities and health care professionals to focus on the mental health aspect of COVID-19 and arrange for necessary support mechanisms.

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