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Crosstalk between peripheral metabolic organs and the central nervous system is essential for body weight control. At the base of the hypothalamus, ß-tanycytes surround the portal capillaries and function as gatekeepers to facilitate transfer of substances from the circulation into the cerebrospinal fluid and vice versa. Here, we investigated the role of the neuroplasticity gene doublecortin-like (DCL), highly expressed by ß-tanycytes, in body weight control and whole-body energy metabolism. We demonstrated that DCL-knockdown through a doxycycline-inducible shRNA expression system prevents body weight gain by reducing adiposity in mice. DCL-knockdown slightly increased whole-body energy expenditure possibly as a result of elevated circulating thyroid hormones. In white adipose tissue (WAT) triglyceride uptake was increased while the average adipocyte cell size was reduced. At histological level we observed clear signs of browning, and thus increased thermogenesis in WAT. We found no indications for stimulated thermogenesis in brown adipose tissue (BAT). Altogether, we demonstrate an important, though subtle, role of tanycytic DCL in body weight control through regulation of energy expenditure, and specifically WAT browning. Elucidating mechanisms underlying the role of DCL in regulating brain-peripheral crosstalk further might identify new treatment targets for obesity.
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Tejido Adiposo Blanco , Metabolismo Energético , Obesidad , Animales , Ratones , Obesidad/metabolismo , Obesidad/genética , Tejido Adiposo Blanco/metabolismo , Masculino , Tejido Adiposo Pardo/metabolismo , Termogénesis/genética , Técnicas de Silenciamiento del Gen , Proteínas de Dominio Doblecortina , Peso Corporal , Ratones Endogámicos C57BL , Tejido Adiposo/metabolismo , Adiposidad/genéticaRESUMEN
Estrone and estradiol differentially modulate neuroplasticity and cognition. How they influence the maturation of new neurons in the adult hippocampus, however, is not known. The present study assessed the effects of estrone and estradiol on the maturation timeline of neurogenesis in the dentate gyrus (DG) of ovariectomized (a model of surgical menopause) young adult Sprague-Dawley rats using daily subcutaneous injections of 17ß-estradiol, estrone or vehicle. Rats were injected with a DNA synthesis marker, 5-bromo-2-deoxyuridine (BrdU), and were perfused 1, 2, or 3 weeks after BrdU injection and daily hormone treatment. Brains were sectioned and processed for various markers including: sex-determining region Y-box 2 (Sox2), glial fibrillary acidic protein (GFAP), antigen kiel 67 (Ki67), doublecortin (DCX), and neuronal nuclei (NeuN). Immunofluorescent labeling or co-labelling of BrdU with Sox2 (progenitor cells), Sox2/GFAP (neural progenitor cells), Ki67 (cell proliferation), DCX (immature neurons), NeuN (mature neurons) was used to examine the trajectory and maturation of adult-born neurons over time. Estrogens had early (1 week of exposure) effects on different stages of neurogenesis (neural progenitor cells, cell proliferation and early maturation of new cells into neurons) but these effects were less pronounced after prolonged treatment. Estradiol enhanced, whereas estrone reduced cell proliferation after 1 week but not after longer exposure to either estrogen. Both estrogens increased the density of immature neurons (BrdU/DCX-ir) after 1 week of exposure compared to vehicle treatment but this increased density was not sustained over longer durations of treatments to estrogens, suggesting that the enhancing effects of estrogens on neurogenesis were short-lived. Longer duration post-ovariectomy, without treatments with either of the estrogens, was associated with reduced neural progenitor cells in the DG. These results demonstrate that estrogens modulate several aspects of adult hippocampal neurogenesis differently in the short term, but may lose their ability to influence neurogenesis after long-term exposure. These findings have potential implications for treatments involving estrogens after surgical menopause.
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The arginine vasopressin (AVP)-magnocellular neurosecretory system (AVPMNS) in the hypothalamus plays a critical role in homeostatic regulation as well as in allostatic motivational behaviors. However, it remains unclear whether adult neurogenesis exists in the AVPMNS. By using immunoreaction against AVP, neurophysin II, glial fibrillar acidic protein (GFAP), cell division marker (Ki67), migrating neuroblast markers (doublecortin, DCX), microglial marker (Ionized calcium binding adaptor molecule 1, Iba1), and 5'-bromo-2'-deoxyuridine (BrdU), we report morphological evidence that low-rate neurogenesis and migration occur in adult AVPMNS in the rat hypothalamus. Tangential AVP/GFAP migration routes and AVP/DCX neuronal chains as well as ascending AVP axonal scaffolds were observed. Chronic water deprivation significantly increased the BrdU+ nuclei within both the supraaoptic (SON) and paraventricular (PVN) nuclei. These findings raise new questions about AVPMNS's potential hormonal role for brain physiological adaptation across the lifespan, with possible involvement in coping with homeostatic adversities.
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Movimiento Celular , Proteína Doblecortina , Neurogénesis , Neuronas , Animales , Ratas , Neuronas/metabolismo , Neuronas/citología , Masculino , Núcleo Hipotalámico Paraventricular/metabolismo , Núcleo Hipotalámico Paraventricular/citología , Hipotálamo/metabolismo , Hipotálamo/citología , Arginina Vasopresina/metabolismoRESUMEN
The complex morphology of neurons requires precise control of their microtubule cytoskeleton. This is achieved by microtubule-associated proteins (MAPs) that regulate the assembly and stability of microtubules, and transport of molecules and vesicles along them. While many of these MAPs function in all cells, some are specifically or predominantly involved in regulating microtubules in neurons. Here we use the sea anemone Nematostella vectensis as a model organism to provide new insights into the early evolution of neural microtubule regulation. As a cnidarian, Nematostella belongs to an outgroup to all bilaterians and thus occupies an informative phylogenetic position for reconstructing the evolution of nervous system development. We identified an ortholog of the microtubule-binding protein doublecortin-like kinase (NvDclk1) as a gene that is predominantly expressed in neurons and cnidocytes (stinging cells), two classes of cells belonging to the neural lineage in cnidarians. A transgenic NvDclk1 reporter line revealed an elaborate network of neurite-like processes emerging from cnidocytes in the tentacles and the body column. A transgene expressing NvDclk1 under the control of the NvDclk1 promoter suggests that NvDclk1 localizes to microtubules and therefore likely functions as a microtubule-binding protein. Further, we generated a mutant for NvDclk1 using CRISPR/Cas9 and show that the mutants fail to generate mature cnidocytes. Our results support the hypothesis that the elaboration of programs for microtubule regulation occurred early in the evolution of nervous systems.
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Quinasas Similares a Doblecortina , Neuronas , Anémonas de Mar , Animales , Anémonas de Mar/embriología , Anémonas de Mar/citología , Anémonas de Mar/genética , Neuronas/metabolismo , Neuronas/citología , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Microtúbulos/metabolismo , Neurogénesis/fisiología , Animales Modificados Genéticamente , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Asociadas a Microtúbulos/genéticaRESUMEN
The central nervous system of Pacific salmon retains signs of embryonic structure throughout life and a large number of neuroepithelial neural stem cells (NSCs) in the proliferative areas of the brain, in particular. However, the adult nervous system and neurogenesis studies on rainbow trout, Oncorhynchus mykiss, are limited. Here, we studied the localization of glutamine synthetase (GS), vimentin (Vim), and nestin (Nes), as well as the neurons formed in the postembryonic period, labeled with doublecortin (DC), under conditions of homeostatic growth in adult cerebellum and brainstem of Oncorhynchus mykiss using immunohistochemical methods and Western Immunoblotting. We observed that the distribution of vimentin (Vim), nestin (Nes), and glutamine synthetase (GS), which are found in the aNSPCs of both embryonic types (neuroepithelial cells) and in the adult type (radial glia) in the cerebellum and the brainstem of trout, has certain features. Populations of the adult neural stem/progenitor cells (aNSPCs) expressing GS, Vim, and Nes have different morphologies, localizations, and patterns of cluster formation in the trout cerebellum and brainstem, which indicates the morphological and, obviously, functional heterogeneity of these cells. Immunolabeling of PCNA revealed areas in the cerebellum and brainstem of rainbow trout containing proliferating cells which coincide with areas expressing Vim, Nes, and GS. Double immunolabeling revealed the PCNA/GS PCNA/Vim coexpression patterns in the neuroepithelial-type cells in the PVZ of the brainstem. PCNA/GS coexpression in the RG was detected in the submarginal zone of the brainstem. The results of immunohistochemical study of the DC distribution in the cerebellum and brainstem of trout have showed a high level of expression of this marker in various cell populations. This may indicate: (i) high production of the adult-born neurons in the cerebellum and brainstem of adult trout, (ii) high plasticity of neurons in the cerebellum and brainstem of trout. We assume that the source of new cells in the trout brain, along with PVZ and SMZ, containing proliferating cells, may be local neurogenic niches containing the PCNA-positive and silent (PCNA-negative), but expressing NSC markers, cells. The identification of cells expressing DC, Vim, and Nes in the IX-X cranial nerve nuclei of trout was carried out.
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Tronco Encefálico , Cerebelo , Células-Madre Neurales , Neurogénesis , Plasticidad Neuronal , Oncorhynchus mykiss , Animales , Oncorhynchus mykiss/metabolismo , Oncorhynchus mykiss/crecimiento & desarrollo , Cerebelo/metabolismo , Cerebelo/citología , Cerebelo/crecimiento & desarrollo , Neurogénesis/fisiología , Plasticidad Neuronal/fisiología , Células-Madre Neurales/metabolismo , Células-Madre Neurales/citología , Tronco Encefálico/metabolismo , Tronco Encefálico/citología , Vimentina/metabolismo , Neuronas/metabolismo , Neuronas/citología , Antígeno Nuclear de Célula en Proliferación/metabolismo , Glutamato-Amoníaco Ligasa/metabolismoRESUMEN
Doublecortin, encoded by the DCX gene, plays a crucial role in the neuronal migration process during brain development. Pathogenic variants of the DCX gene are the major causes of the "lissencephaly (LIS) spectrum", which comprehends a milder phenotype like Subcortical Band Heterotopia (SBH) in heterozygous female subjects. We performed targeted sequencing in three unrelated female cases with SBH. We identified three DCX-related variants: a novel missense (c.601A>G: p.Lys201Glu), a novel nonsense (c.210C>G: p.Tyr70*), and a previously identified nonsense (c.907C>T: p.Arg303*) variant. The novel c.601A>G: p.Lys201Glu variant shows a mother-daughter transmission pattern across four generations. The proband exhibits focal epilepsy and achieved seizure freedom with a combination of oxcarbazepine and levetiracetam. All other affected members have no history of epileptic seizures. Brain MRIs of the affected members shows predominant fronto-central SBH with mixed pachygyria on the overlying cortex. The two nonsense variants were identified in two unrelated probands with SBH, severe drug-resistant epilepsy and intellectual disability. These novel DCX variants further expand the genotypic-phenotypic correlations of lissencephaly spectrum disorders. Our documented phenotypic descriptions of three unrelated families provide valuable insights and stimulate further discussions on DCX-SBH cases.
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Lisencefalias Clásicas y Heterotopias Subcorticales en Banda , Proteína Doblecortina , Fenotipo , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lisencefalias Clásicas y Heterotopias Subcorticales en Banda/genética , Lisencefalias Clásicas y Heterotopias Subcorticales en Banda/patología , Codón sin Sentido/genética , Imagen por Resonancia Magnética , Mutación MissenseRESUMEN
BACKGROUND/AIM: Although several studies in some neoplasms have reported correlation between the expression levels of Doublecortin-like kinase1(DCLK1) and carcinogenesis, its role in cholangiocarcinoma remains unknown. MATERIALS AND METHODS: DCLK1 expression in normal epithelium (NE), biliary intraepithelial neoplasia (BilIN)1â¼3, and intrahepatic cholangiocarcinoma (ICC) were investigated immuno-histochemically. The molecular effects of DCLK1 were investigated by gene silencing using RNAi [DCLK1-tagrgeting (siDCLK1)]. The human ICC cell lines HuCCT1 and HuH28 were transfected with these siRNAs, and used for assays in the presence or absence of DCLK1 inhibitors. RESULTS: The positive ratio of DCLK1 expression in ICC was higher than that in NE, and equally distributed among BilIN1â¼3 (NE: BilIN1: BilIN2: BilIN3: ICC=62%: 91%: 97%: 100%: 95%, p<0.05). In the wound healing assay, the migration of the siDCLK1-treated cells was significantly inhibited compared to the NT-treated cells (p<0.05). In the cell invasion assay, the invasion of the siDCLK1-treated cells was significantly inhibited compared to the NT-treated cells (p<0.05). In the presence of the DCLK1 inhibitor, cell proliferative capacity at 24 hours was decreased in a concentration-dependent manner. CONCLUSION: DCLK1 was highly expressed in the early stage of ICC carcinogenesis. Human ICC cell growth was suppressed in vitro by siRNA silencing of DCLK1 or after treatment with the DCLK1 inhibitor, indicating DCLK1 may be molecular target for ICC therapy.
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Neoplasias de los Conductos Biliares , Colangiocarcinoma , Quinasas Similares a Doblecortina , Péptidos y Proteínas de Señalización Intracelular , Proteínas Serina-Treonina Quinasas , Humanos , Colangiocarcinoma/genética , Colangiocarcinoma/patología , Colangiocarcinoma/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias de los Conductos Biliares/patología , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Regulación Neoplásica de la Expresión Génica , Estadificación de Neoplasias , Masculino , Proliferación Celular , Persona de Mediana Edad , Femenino , ARN Interferente Pequeño/genética , Carcinoma in Situ/patología , Carcinoma in Situ/genética , Carcinoma in Situ/metabolismoRESUMEN
Head and neck squamous cell carcinoma (HNSCC) is a major health concern due to its high mortality from poor treatment responses and locoregional tumor invasion into life sustaining structures in the head and neck. A deeper comprehension of HNSCC invasion mechanisms holds the potential to inform targeted therapies that may enhance patient survival. We previously reported that doublecortin like kinase 1 (DCLK1) regulates invasion of HNSCC cells. Here, we tested the hypothesis that DCLK1 regulates proteins within invadopodia to facilitate HNSCC invasion. Invadopodia are specialized subcellular protrusions secreting matrix metalloproteinases that degrade the extracellular matrix (ECM). Through a comprehensive proteome analysis comparing DCLK1 control and shDCLK1 conditions, our findings reveal that DCLK1 plays a pivotal role in regulating proteins that orchestrate cytoskeletal and ECM remodeling, contributing to cell invasion. Further, we demonstrate in TCGA datasets that DCLK1 levels correlate with increasing histological grade and lymph node metastasis. We identified higher expression of DCLK1 in the leading edge of HNSCC tissue. Knockdown of DCLK1 in HNSCC reduced the number of invadopodia, cell adhesion and colony formation. Using super resolution microscopy, we demonstrate localization of DCLK1 in invadopodia and colocalization with mature invadopodia markers TKS4, TKS5, cortactin and MT1-MMP. We carried out phosphoproteomics and validated using immunofluorescence and proximity ligation assays, the interaction between DCLK1 and motor protein KIF16B. Pharmacological inhibition or knockdown of DCLK1 reduced interaction with KIF16B, secretion of MMPs, and cell invasion. This research unveils a novel function of DCLK1 within invadopodia to regulate the trafficking of matrix degrading cargo. The work highlights the impact of targeting DCLK1 to inhibit locoregional invasion, a life-threatening attribute of HNSCC.
RESUMEN
Doublecortin (DCX)-positive neural progenitor-like cells are purported components of the cancer microenvironment. The number of DCX-positive cells in tissues reportedly correlates with cancer progression; however, little is known about the mechanism by which these cells affect cancer progression. Here we demonstrated that DCX-positive cells, which are found in all major histological subtypes of lung cancer, are cancer-associated Schwann cells (CAS) and contribute to the chemoresistance of lung cancer cells by establishing an adrenergic microenvironment. Mechanistically, the activation of the Hippo transducer YAP/TAZ was involved in the acquisition of new traits of CAS and DCX positivity. We further revealed that CAS express catecholamine-synthesizing enzymes and synthesize adrenaline, which potentiates the chemoresistance of lung cancer cells through the activation of YAP/TAZ. Our findings shed light on CAS, which drive the formation of an adrenergic microenvironment by the reciprocal regulation of YAP/TAZ in lung cancer tissues.
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Resistencia a Antineoplásicos , Neoplasias Pulmonares , Neuropéptidos , Células de Schwann , Factores de Transcripción , Microambiente Tumoral , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neuropéptidos/metabolismo , Células de Schwann/metabolismo , Células de Schwann/patología , Línea Celular Tumoral , Factores de Transcripción/metabolismo , Animales , Proteína Doblecortina , Ratones , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Señalizadoras YAP/metabolismo , Proteínas Señalizadoras YAP/genética , Proteínas Coactivadoras Transcripcionales con Motivo de Unión a PDZ/metabolismo , Epinefrina/metabolismo , Epinefrina/farmacología , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Masculino , FemeninoRESUMEN
Parkinson's disease (PD) is a complex neurodegenerative disorder characterized by motor and non-motor symptoms. Motor symptoms include bradykinesia, resting tremors, muscular rigidity, and postural instability, while non-motor symptoms include cognitive impairments, mood disturbances, sleep disturbances, autonomic dysfunction, and sensory abnormalities. Some of these symptoms may be influenced by the proper hippocampus functioning, including adult neurogenesis. Doublecortin (DCX) is a microtubule-associated protein that plays a pivotal role in the development and differentiation of migrating neurons. This study utilized postmortem human brain tissue of PD and age-matched control individuals to investigate DCX expression in the context of adult hippocampal neurogenesis. Our findings demonstrate a significant reduction in the number of DCX-expressing cells within the subgranular zone (SGZ), as well as a decrease in the nuclear area of these DCX-positive cells in postmortem brain tissue obtained from PD cases, suggesting an impairment in the adult hippocampal neurogenesis. Additionally, we found that the nuclear area of DCX-positive cells correlates with pH levels. In summary, we provide evidence supporting that the process of hippocampal adult neurogenesis is likely to be compromised in PD patients before cognitive dysfunction, shedding light on potential mechanisms contributing to the neuropsychiatric symptoms observed in affected individuals. Understanding these mechanisms may offer novel insights into the pathophysiology of PD and possible therapeutic avenues.
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Proteínas de Dominio Doblecortina , Proteína Doblecortina , Hipocampo , Proteínas Asociadas a Microtúbulos , Neurogénesis , Neuropéptidos , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/patología , Hipocampo/metabolismo , Masculino , Neuropéptidos/metabolismo , Neuropéptidos/biosíntesis , Anciano , Proteínas Asociadas a Microtúbulos/metabolismo , Femenino , Neurogénesis/fisiología , Anciano de 80 o más Años , Persona de Mediana EdadRESUMEN
Doublecortin-like kinase 1 (DCLK1) is a microtubule-associated protein kinase involved in neurogenesis and human cancer. Recent studies have revealed a novel functional role for DCLK1 in inflammatory signaling, thus positioning it as a novel target kinase for respiratory inflammatory disease treatment. In this study, we designed and synthesized a series of NVP-TAE684-based derivatives as novel anti-inflammatory agents targeting DCLK1. Bio-layer interferometry binding screening and kinase assays of the NVP-TAE684 derivatives led to the discovery of an effective DCLK1 inhibitor (a24), with an IC50 of 179.7 nM. Compound a24 effectively inhibited lipopolysaccharide (LPS)-induced inflammation in macrophages with higher potency than the lead compound. Mechanistically, compound a24 inhibited LPS-induced inflammation by inhibiting DCLK1-mediated IKKß phosphorylation. Furthermore, compound a24 showed in vivo anti-inflammatory activity in an LPS-challenged acute lung injury model. These findings suggest that compound a24 may serve as a novel candidate for the development of DCLK1 inhibitors and a potential therapeutic agent for the treatment of inflammatory diseases.
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Lesión Pulmonar Aguda , Quinasas Similares a Doblecortina , Humanos , Péptidos y Proteínas de Señalización Intracelular , Lipopolisacáridos/farmacología , Proteínas Serina-Treonina Quinasas , Inflamación/tratamiento farmacológico , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológicoRESUMEN
BACKGROUND: Over the years, animal models of depression have been developed by loading chronic stress, inducing neuroinflammation, or administering drugs that induce depression; however, these results have poor reproducibility. Therefore, it is necessary to develop animal models that exhibit definitive symptoms of depression for studies on potential therapeutics. OBJECTIVE: This study was aimed at investigating depression-like symptoms and their pathogenesis in lipopolysaccharide (LPS)-inflamed mice treated with dexamethasone (DEX). METHODS: Male ICR mice were injected with LPS, followed by injection with DEX a day later and each day for 6 consecutive days. Depression-like behavior, expression of the glial markers glial fibrillary acidic protein (GFAP) and ionized calcium-binding adapter molecule 1 (Iba1), and the number of the immature neuronal marker doublecortin (DCX)-positive cells were assessed using tail-suspension test (TST), forced swim test (FST), western blot analysis, and immunohistochemical analysis. RESULTS: Mice in the LPS+DEX group had significantly longer immobility time in the TST and FST than did those in the LPS- or DEX-only and control groups on day 7 post-LPS administration. GFAP and Iba1 expression was significantly elevated in the hippocampus of mice in the LPS group than in those of mice in the control group. Moreover, a significantly lower number of DCX-positive cells was observed in the hippocampal dentate gyrus of mice in the LPS+DEX group compared with that in mice in the LPS- or DEX-only and control groups on day 7 after LPS administration. CONCLUSION: Repeated DEX administration to LPS-inflamed mice may induce definitive depression-like symptoms by decreasing the number of immature neurons in the hippocampal dentate gyrus. This novel mouse model of depression was produced by repeated administration of steroids to inflamed mice.
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BACKGROUND: The neurogenesis hypothesis is a promising candidate etiologic hypothesis for depression, and it is associated with electroconvulsive therapy (ECT). However, human in vivo molecular-level evidence is lacking. OBJECTIVE: We used neuron-derived extracellular vesicles (NDEVs) as a "window to the neurons" to explore the in vivo neurogenesis status associated with ECT in patients with treatment-resistant depression (TRD). METHODS: In this study, we enrolled 40 patients with TRD and 35 healthy controls (HCs). We isolated NDEVs from the plasma of each participant to test the levels of doublecortin (DCX), a marker of neurogenesis, and cluster of differentiation (CD) 81, a marker of EVs. We also assessed the plasma levels of brain-derived neurotrophic factor (BDNF), a protein that is known to be associated with ECT and neuroplastic processes. RESULTS: Our findings indicated that both the levels of DCX in NDEVs and BDNF in plasma were significantly lower in TRD patients compared to HCs at baseline, but increased following ECTs. Conversely, levels of CD81 in NDEVs were found higher in TRD patients at baseline, but did not change after the ECT treatments. Exploratory analyses revealed that lower levels of BDNF in plasma and DCX in NDEVs, along with higher CD81 levels in NDEVs, were associated with more severe depressive symptoms and reduced cognitive function at baseline. Furthermore, higher baseline CD81 concentrations in NDEVs were correlated with greater decreases in depression symptoms. CONCLUSIONS: We first present human in vivo evidence of early neurogenesis using DCX through NDEVs: decreased in TRD patients, increased after ECTs.
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Trastorno Depresivo Resistente al Tratamiento , Terapia Electroconvulsiva , Humanos , Factor Neurotrófico Derivado del Encéfalo , Depresión/terapia , Resultado del Tratamiento , Trastorno Depresivo Resistente al Tratamiento/terapiaRESUMEN
A wide variety of CreERT2 driver lines are available for genetic manipulation of adult-born neurons in the mouse brain. These tools have been instrumental in studying fate potential, migration, circuit integration, and morphology of the stem cells supporting lifelong neurogenesis. Despite a wealth of tools, genetic manipulation of adult-born neurons for circuit and behavioral studies has been limited by poor specificity of many driver lines targeting early progenitor cells and by the inaccessibility of lines selective for later stages of neuronal maturation. We sought to address these limitations by creating a new CreERT2 driver line targeted to the endogenous mouse doublecortin locus as a marker of fate-specified neuroblasts and immature neurons. Our new model places a T2A-CreERT2 cassette immediately downstream of the Dcx coding sequence on the X chromosome, allowing expression of both Dcx and CreERT2 proteins in the endogenous spatiotemporal pattern for this gene. We demonstrate that the new mouse line drives expression of a Cre-dependent reporter throughout the brain in neonatal mice and in known neurogenic niches of adult animals. The line has been deposited with the Jackson Laboratory and should provide an accessible tool for studies targeting fate-restricted neuronal precursors.
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Células-Madre Neurales , Neuronas , Ratones , Animales , Ratones Transgénicos , Neuronas/metabolismo , Células-Madre Neurales/metabolismo , Neurogénesis/genética , EncéfaloRESUMEN
Motopsin, a serine protease encoded by PRSS12, is secreted by neuronal cells into the synaptic clefts in an activity-dependent manner, where it induces synaptogenesis by modulating Na+/K+-ATPase activity. In humans, motopsin deficiency leads to severe intellectual disability and, in mice, it disturbs spatial memory and social behavior. In this study, we investigated mice that overexpressed motopsin in the forebrain using the Tet-Off system (DTG-OE mice). The elevated agrin cleavage or the reduced Na+/K+-ATPase activity was not detected. However, motopsin overexpression led to a reduction in spine density in hippocampal CA1 basal dendrites. While motopsin overexpression decreased the ratio of mature mushroom spines in the DG, it increased the ratio of immature thin spines in CA1 apical dendrites. Female DTG-OE mice showed elevated locomotor activity in their home cages. DTG-OE mice showed aberrant behaviors, such as delayed latency to the target hole in the Barnes maze test and prolonged duration of sniffing objects in the novel object recognition test (NOR), although they retained memory comparable to that of TRE-motopsin littermates, which normally express motopsin. After NOR, c-Fos-positive cells increased in the dentate gyrus (DG) of DTG-OE mice compared with that of DTG-SO littermates, in which motopsin overexpression was suppressed by the administration of doxycycline, and TRE-motopsin littermates. Notably, the numbers of doublecortin- and 5-bromo-2'-deoxyuridine-labeled cells significantly increased in the DG of DTG-OE mice, suggesting increased adult neurogenesis. Importantly, our results revealed a new function in addition to modulating neuronal responsiveness and spine morphology in the DG: the regulation of neurogenesis.
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Giro Dentado , Discapacidad Intelectual , Neurogénesis , Neuronas , Animales , Femenino , Masculino , Ratones , Espinas Dendríticas/metabolismo , Giro Dentado/metabolismo , Discapacidad Intelectual/genética , Discapacidad Intelectual/metabolismo , Ratones Endogámicos C57BL , Ratones Transgénicos , Neurogénesis/fisiología , Neuronas/metabolismo , Serina Proteasas/metabolismo , Serina Proteasas/genéticaRESUMEN
Doublecortin-like kinase 1 (DCLK) is a microtubule-associated serine/threonine kinase that is upregulated in a wide range of cancers and is believed to be related to tumour growth and development. Upregulated DCLK1 has been used to identify patients at high risk of cancer progression and tumours with chemotherapy-resistance. Moreover, DCLK1 has been identified as a cancer stem cell (CSC) biomarker in various cancers, which has received considerable attention recently. Herein, a series of DCLK1 inhibitors were prepared based on the previously reported XMD8-92 structure. Among all the synthesised compounds, D1, D2, D6, D7, D8, D12, D14, and D15 showed higher DCLK1 inhibitory activities (IC50 40-74 nM) than XMD8-92 (IC50 161 nM). Compounds D1 and D2 were selective DCLK1 inhibitors as they showed a rather weak inhibitory effect on LRRK2. The antiproliferative activities of these compounds were also preliminarily evaluated. The structure-activity relationship revealed by our compounds provides useful guidance for the further development of DCLK1 inhibitors.
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Quinasas Similares a Doblecortina , Inhibidores de Proteínas Quinasas , Humanos , Quinasas Similares a Doblecortina/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Relación Estructura-Actividad , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacologíaRESUMEN
The PTEN gene negatively regulates the oncogenic PI3K-AKT pathway by encoding a lipid and protein phosphatase that dephosphorylates lipid phosphatidylinositol-3,4,5-triphosphate (PIP3) resulting in the inhibition of PI3K and downstream inhibition of AKT. Overexpression of PTEN in mice leads to a longer lifespan compared to control littermates, although the mechanism is unknown. Here, we provide evidence that young adult PTENOE mice exhibit many characteristics shared by other slow-aging mouse models, including those with mutations that affect GH/IGF1 pathways, calorie-restricted mice, and mice treated with anti-aging drugs. PTENOE white adipose tissue (WAT) has increased UCP1, a protein linked to increased thermogenesis. WAT of PTENOE mice also shows a change in polarization of fat-associated macrophages, with elevated levels of arginase 1 (Arg1, characteristic of M2 macrophages) and decreased production of inducible nitric oxide synthase (iNOS, characteristic of M1 macrophages). Muscle and hippocampus showed increased expression of the myokine FNDC5, and higher levels of its cleavage product irisin in plasma, which has been linked to increased conversion of WAT to more thermogenic beige/brown adipose tissue. PTENOE mice also have an increase, in plasma and liver, of GPLD1, which is known to improve cognition in mice. Hippocampus of the PTENOE mice has elevation of both BDNF and DCX, indices of brain resilience and neurogenesis. These changes in fat, macrophages, liver, muscle, hippocampus, and plasma may be considered "aging rate indicators" in that they seem to be consistently changed across many of the long-lived mouse models and may help to extend lifespan by delaying many forms of late-life illness. Our new findings show that PTENOE mice can be added to the group of long-lived mice that share this multi-tissue suite of biochemical characteristics.
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Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Animales , Ratones , Envejecimiento , Fibronectinas/metabolismo , Lípidos , Fenotipo , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/genéticaRESUMEN
AIM:To investigate the effect of doublecortin-like kinase 1(DCLK1)on the biological properties of gastric cancer stem cells,and to explore its possible mechanism.METHODS:Serum-free suspension culture of gastric cancer stem cells and targeted inhibition of DCLK1 activity in gastric cancer stem cells with DCLK1 inhibitor DCLK1-IN-1 were performed.The expression levels of DCLK1,stemness-related proteins(SOX2 and OCT4),proliferation-related pro-teins(cyclin D1 and c-MYC),drug resistance-related proteins(ABCG2 and TOP2A),epithelial-mesenchymal transition-related proteins(E-cadherin,vimentin and Snail),and PI3K/AKT/mTOR signaling pathway-related proteins in gastric cancer stem cells were examined by Western blot.The effects of DCLK1 on viability and drug resistance of gastric cancer stem cells were determined by CCK-8 assay,and the effects of DCLK1 on self-renewal of gastric cancer stem cells were de-termined by methylcellulose spheroid-forming assay.Wound-healing and Transwell assays were performed to assess the ef-fect of DCLK1 on the migration and invasion of gastric cancer stem cells.RESULTS:The expression levels of DCLK1 and stemness-related proteins SOX2 and OCT4 in gastric cancer stem cells were significantly higher than those in parental cells(P<0.01).The proliferation,drug resistance,migration and invasion of gastric cancer stem cells in DCLK1 inhibi-tion group were significantly lower than those in Sphere cell group(P<0.01).The expression levels of proliferation-related proteins(c-MYC and cyclin D1)and drug resistance-related proteins(TOP2A and ABCG2)were down-regulated,the ex-pression of epithelial marker E-cadherin was up-regulated,the expression of mesenchymal markers vimentin and Snail was down-regulated,and the expression levels of PI3K/AKT/mTOR signaling pathway-related proteins and their phosphoryla-tion levels were reduced in DCLK1 inhibition group(P<0.05).CONCLUSION:DCLK1 is highly expressed in gastric cancer stem cells,which may be involved in the proliferation,drug resistance and invasion of gastric cancer stem cells by regulating PI3K/AKT/mTOR signaling pathway.It suggests that DCLK1 can be used as a potential target for gastric cancer stem cells.
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Objective To investigate the effects of doublecortin-like kinase 1 (DCLK1) on the malignant biological behaviors, such as proliferation, migration, and invasion, of A549 cell line and their corresponding mechanisms. Methods DCLK1-overexpressing A549 cell lines were established through lentiviral infection, and DCLK1 expression was validated by using RT-PCR and Western blot analysis. Proliferation ability was assessed with CCK-8 and plate cloning assays, and migration and invasion abilities were examined with Transwell assays. The pathway regulated by DCLK1 in lung adenocarcinoma was analyzed on the basis of the TCGA lung adenocarcinoma cohort with pathway enrichment analysis and verified through Western blot analysis. Results DCLK1 overexpression in A549 cells promoted cell proliferation, migration, and invasion. The inhibition of the FAK/PI3K/AKT/mTOR signaling pathway impaired the DCLK1-mediated malignant behavior of A549 cells. Conclusion DCLK1 promotes the malignant behavior of A549 cells through the activation of the FAK/PI3K/AKT/mTOR signaling pathway.
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@#Objective To investigate the value of receiver operating curve human papilloma virus(HPV)-DNA typing combined with serum neutrophil lymphocyte ratio(NLR)and bicorticoid kinase 1(DCLK1)levels in the early diagnosis of cervical cancer.Methods A total of 120 patients with early cervical cancer diagnosed in our obstetrics and gynecology department from August 2018 to June 2022 were randomly included as cervical cancer group,and 120 patients with benign lesions were included as benign group.The level of DCLK1 was detected by ELISA;NLR was detected by automatic blood cell analyzer;HPV subtypes in cervical secretions were detected by HPV genotyping gene chip detection system;the cut-off values of serum NLR and DCLK1 levels in the diagnosis of cervical cancer were analyzed by using the receiver operator curve(ROC);four table method was applied to analyze the diagnostic value of HPV-DNA typing,serum NLR,DCLK1 levels alone and in combination for cervical cancer.Results Compared with benign group,the levels of serum NLR and DCLK1 in cervical cancer group were obviously higher(P<0.05).The positive rate of HR-HPV in cervical cancer group was obviously higher than that in benign group(P<0.05).The ROC curve was drawn with serum NLR and DCLK1 levels as test variables,the results showed that the AUC of serum NLR and DCLK1 predicting early cervical cancer was 0.724 and 0.718,respectively,and the cut-off value was 3.08 and 3.32,respectively.HPV-DNA typing combined with serum NLR and DCLK1 detected 18 false positives and 17 false negatives,Kappa value was 0.725,which was consistent with pathological results.The sensitivity,negative predictive value and accuracy of HPV-DNA typing combined with serum NLR and DCLK1 levels in the diagnosis of early cervical cancer were obviously higher than those of HPV-DNA typing,serum NLR and DCLK1 levels alone(P<0.05).Conclusion The results of HPV-DNA typing combined with NLR and DCLK1 in the diagnosis of early cervical cancer are highly consistent with the pathological results,and the sensitivity and accuracy are obviously improved.