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1.
J Neurosci ; 43(29): 5277-5289, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37369589

RESUMO

Neural circuit assembly is a multistep process where synaptic partners are often born at distinct developmental stages, and yet they must find each other and form precise synaptic connections with one another. This developmental process often relies on late-born neurons extending their processes to the appropriate layer to find and make synaptic connections to their early-born targets. The molecular mechanism responsible for the integration of late-born neurons into an emerging neural circuit remains unclear. Here, we uncovered a new role for the cytoskeletal protein ßII-spectrin in properly positioning presynaptic and postsynaptic neurons to the developing synaptic layer. Loss of ßII-spectrin disrupts retinal lamination, leads to synaptic connectivity defects, and results in impaired visual function in both male and female mice. Together, these findings highlight a new function of ßII-spectrin in assembling neural circuits in the mouse outer retina.SIGNIFICANCE STATEMENT Neurons that assemble into a functional circuit are often integrated at different developmental time points. However, the molecular mechanism that guides the precise positioning of neuronal processes to the correct layer for synapse formation is relatively unknown. Here, we show a new role for the cytoskeletal scaffolding protein, ßII-spectrin in the developing retina. ßII-spectrin is required to position presynaptic and postsynaptic neurons to the nascent synaptic layer in the mouse outer retina. Loss of ßII-spectrin disrupts positioning of neuronal processes, alters synaptic connectivity, and impairs visual function.


Assuntos
Proteínas do Citoesqueleto , Espectrina , Masculino , Camundongos , Feminino , Animais , Espectrina/metabolismo , Neurônios/metabolismo , Citoesqueleto/metabolismo
2.
BMC Cancer ; 24(1): 853, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026155

RESUMO

BACKGROUND: Metformin, a widely prescribed antidiabetic drug, has shown several promising effects for cancer treatment. These effects have been shown to be mediated by dual modulation of the AMPK-mTORC1 axis, where AMPK acts upstream of mTORC1 to decrease its activity. Nevertheless, alternative pathways have been recently discovered suggesting that metformin can act through of different targets regulation. METHODS: We performed a transcriptome screening analysis using HeLa xenograft tumors generated in NOD-SCID mice treated with or without metformin to examine genes regulated by metformin. Western Blot analysis, Immunohistochemical staining, and RT-qPCR were used to confirm alterations in gene expression. The TNMplot and GEPIA2 platform were used for in silico analysis of genes found up-regulated by metformin, in cervical cancer patients. We performed an AMPK knock-down using AMPK-targeted siRNAs and mTOR inhibition with rapamycin to investigate the molecular mechanisms underlying the effect of metformin in cervical cancer cell lines. RESULTS: We shown that metformin decreases tumor growth and increased the expression of a group of antitumoral genes involved in DNA-binding transcription activator activity, hormonal response, and Dcp1-Dcp2 mRNA-decapping complex. We demonstrated that ZFP36 could act as a new molecular target increased by metformin. mTORC1 inhibition using rapamycin induces ZFP36 expression, which could suggest that metformin increases ZFP36 expression and requires mTORC1 inhibition for such effect. Surprisingly, in HeLa cells AMPK inhibition did not affect ZFP36 expression, suggesting that additional signal transducers related to suppressing mTORC1 activity, could be involved. CONCLUSIONS: These results highlight the importance of ZFP36 activation in response to metformin treatment involving mTORC1 inhibition.


Assuntos
Alvo Mecanístico do Complexo 1 de Rapamicina , Metformina , Neoplasias do Colo do Útero , Ensaios Antitumorais Modelo de Xenoenxerto , Humanos , Metformina/farmacologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/genética , Feminino , Animais , Camundongos , Células HeLa , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Camundongos SCID , Camundongos Endogâmicos NOD , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia
3.
Int J Legal Med ; 138(4): 1459-1496, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38400923

RESUMO

The aim of this systematic review is to analyze the literature to determine whether the methods of artificial intelligence are effective in determining age in panoramic radiographs. Searches without language and year limits were conducted in PubMed/Medline, Embase, Web of Science, and Scopus databases. Hand searches were also performed, and unpublished manuscripts were searched in specialized journals. Thirty-six articles were included in the analysis. Significant differences in terms of root mean square error and mean absolute error were found between manual methods and artificial intelligence techniques, favoring the use of artificial intelligence (p < 0.00001). Few articles compared deep learning methods with machine learning models or manual models. Although there are advantages of machine learning in data processing and deep learning in data collection and analysis, non-comparable data was a limitation of this study. More information is needed on the comparison of these techniques, with particular emphasis on time as a variable.


Assuntos
Determinação da Idade pelos Dentes , Inteligência Artificial , Radiografia Panorâmica , Humanos , Determinação da Idade pelos Dentes/métodos , Aprendizado Profundo , Aprendizado de Máquina
4.
Cell Mol Life Sci ; 79(1): 63, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35006382

RESUMO

Conventional angiogenic factors, such as vascular endothelial growth factor (VEGF), regulate both pathological and physiological angiogenesis indiscriminately, and their inhibitors may elicit adverse side effects. Secretogranin III (Scg3) was recently reported to be a diabetes-restricted VEGF-independent angiogenic factor, but the disease selectivity of Scg3 in retinopathy of prematurity (ROP), a retinal disease in preterm infants with concurrent pathological and physiological angiogenesis, was not defined. Here, using oxygen-induced retinopathy (OIR) mice, a surrogate model of ROP, we quantified an exclusive binding of Scg3 to diseased versus healthy developing neovessels that contrasted sharply with the ubiquitous binding of VEGF. Functional immunohistochemistry visualized Scg3 binding exclusively to disease-related disorganized retinal neovessels and neovascular tufts, whereas VEGF bound to both disorganized and well-organized neovessels. Homozygous deletion of the Scg3 gene showed undetectable effects on physiological retinal neovascularization but markedly reduced the severity of OIR-induced pathological angiogenesis. Furthermore, anti-Scg3 humanized antibody Fab (hFab) inhibited pathological angiogenesis with similar efficacy to anti-VEGF aflibercept. Aflibercept dose-dependently blocked physiological angiogenesis in neonatal retinas, whereas anti-Scg3 hFab was without adverse effects at any dose and supported a therapeutic window at least 10X wider than that of aflibercept. Therefore, Scg3 stringently regulates pathological but not physiological angiogenesis, and anti-Scg3 hFab satisfies essential criteria for development as a safe and effective disease-targeted anti-angiogenic therapy for ROP.


Assuntos
Inibidores da Angiogênese/farmacologia , Cromograninas/imunologia , Cromograninas/metabolismo , Neovascularização Patológica/genética , Neovascularização Retiniana/patologia , Retinopatia da Prematuridade/patologia , Animais , Capilares/metabolismo , Cromograninas/antagonistas & inibidores , Cromograninas/genética , Modelos Animais de Doenças , Fragmentos Fab das Imunoglobulinas/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxigênio/efeitos adversos , Receptores de Fatores de Crescimento do Endotélio Vascular , Proteínas Recombinantes de Fusão/farmacologia , Neovascularização Retiniana/genética , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
6.
J Biol Chem ; 296: 100268, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33837726

RESUMO

Degranulation, a fundamental effector response from mast cells (MCs) and platelets, is an example of regulated exocytosis. This process is mediated by SNARE proteins and their regulators. We have previously shown that several of these proteins are essential for exocytosis in MCs and platelets. Here, we assessed the role of the SNARE protein SNAP23 using conditional knockout mice, in which SNAP23 was selectively deleted from either the megakaryocyte/platelet or connective tissue MC lineages. We found that removal of SNAP23 in platelets results in severe defects in degranulation of all three platelet secretory granule types, i.e., alpha, dense, and lysosomal granules. The mutation also induces thrombocytopenia, abnormal platelet morphology and activation, and reduction in the number of alpha granules. Therefore, the degranulation defect might not be secondary to an intrinsic failure of the machinery mediating regulated exocytosis in platelets. When we removed SNAP23 expression in MCs, there was a complete developmental failure in vitro and in vivo. The developmental defects in platelets and MCs and the abnormal translocation of membrane proteins to the surface of platelets indicate that SNAP23 is also involved in constitutive exocytosis in these cells. The MC conditional deletant animals lacked connective tissue MCs, but their mucosal MCs were normal and expanded in response to an antigenic stimulus. We used this mouse to show that connective tissue MCs are required and mucosal MCs are not sufficient for an anaphylactic response.


Assuntos
Anafilaxia/imunologia , Plaquetas/imunologia , Tecido Conjuntivo/imunologia , Mastócitos/imunologia , Proteínas Qb-SNARE/imunologia , Proteínas Qc-SNARE/imunologia , Anafilaxia/genética , Anafilaxia/patologia , Animais , Plaquetas/patologia , Tecido Conjuntivo/patologia , Exocitose/genética , Exocitose/imunologia , Mastócitos/patologia , Camundongos , Camundongos Knockout , Proteínas Qb-SNARE/genética , Proteínas Qc-SNARE/genética , Vesículas Secretórias/genética , Vesículas Secretórias/imunologia
7.
Hum Genet ; 140(8): 1143-1156, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33974130

RESUMO

Biallelic STX3 variants were previously reported in five individuals with the severe congenital enteropathy, microvillus inclusion disease (MVID). Here, we provide a significant extension of the phenotypic spectrum caused by STX3 variants. We report ten individuals of diverse geographic origin with biallelic STX3 loss-of-function variants, identified through exome sequencing, single-nucleotide polymorphism array-based homozygosity mapping, and international collaboration. The evaluated individuals all presented with MVID. Eight individuals also displayed early-onset severe retinal dystrophy, i.e., syndromic-intestinal and retinal-disease. These individuals harbored STX3 variants that affected both the retinal and intestinal STX3 transcripts, whereas STX3 variants affected only the intestinal transcript in individuals with solitary MVID. That STX3 is essential for retinal photoreceptor survival was confirmed by the creation of a rod photoreceptor-specific STX3 knockout mouse model which revealed a time-dependent reduction in the number of rod photoreceptors, thinning of the outer nuclear layer, and the eventual loss of both rod and cone photoreceptors. Together, our results provide a link between STX3 loss-of-function variants and a human retinal dystrophy. Depending on the genomic site of a human loss-of-function STX3 variant, it can cause MVID, the novel intestinal-retinal syndrome reported here or, hypothetically, an isolated retinal dystrophy.


Assuntos
Oftalmopatias Hereditárias/genética , Mucosa Intestinal/metabolismo , Síndromes de Malabsorção/genética , Microvilosidades/patologia , Mucolipidoses/genética , Polimorfismo de Nucleotídeo Único , Proteínas Qa-SNARE/genética , Células Fotorreceptoras Retinianas Cones/metabolismo , Distrofias Retinianas/genética , Idoso , Idoso de 80 Anos ou mais , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Animais , Autopsia , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Oftalmopatias Hereditárias/metabolismo , Oftalmopatias Hereditárias/patologia , Feminino , Regulação da Expressão Gênica , Homozigoto , Humanos , Mucosa Intestinal/patologia , Síndromes de Malabsorção/metabolismo , Síndromes de Malabsorção/patologia , Camundongos , Camundongos Knockout , Microvilosidades/genética , Microvilosidades/metabolismo , Mucolipidoses/metabolismo , Mucolipidoses/patologia , Fenótipo , Proteínas Qa-SNARE/deficiência , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Fotorreceptoras Retinianas Cones/patologia , Distrofias Retinianas/metabolismo , Distrofias Retinianas/patologia , Rodopsinas Sensoriais/genética , Rodopsinas Sensoriais/metabolismo , Sequenciamento do Exoma
8.
BMC Psychiatry ; 21(1): 86, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33563249

RESUMO

BACKGROUND: Cognitive functions represent useful endophenotypes to identify the association between genetic variants and schizophrenia. In this sense, the NR4A2 gene has been implicated in schizophrenia and cognition in different animal models and clinical trials. We hypothesized that the NR4A2 gene is associated with working memory performance in schizophrenia. This study aimed to analyze two variants and the expression levels of the NR4A2 gene with susceptibility to schizophrenia, as well as to evaluate whether possession of NR4A2 variants influence the possible correlation between gene expression and working memory performance in schizophrenia. METHODS: The current study included 187 schizophrenia patients and 227 controls genotyped for two of the most studied NR4A2 genetic variants in neurological and neuropsychiatric diseases. Genotyping was performed using High Resolution Melt and sequencing techniques. In addition, mRNA expression of NR4A2 was performed in peripheral mononuclear cells of 112 patients and 118 controls. A group of these participants, 54 patients and 87 controls, performed the working memory index of the WAIS III test. RESULTS: Both genotypic frequencies of the two variants and expression levels of the NR4A2 gene showed no significant difference when in patients versus controls. However, patients homozygous for the rs34884856 promoter variant showed a positive correlation between expression levels and auditory working memory. CONCLUSIONS: Our finding suggested that changes in expression levels of the NR4A2 gene could be associated with working memory in schizophrenia depending on patients' genotype in a sample from a Mexican population.


Assuntos
Esquizofrenia , Estudos de Casos e Controles , Humanos , Transtornos da Memória , Memória de Curto Prazo , México , Testes Neuropsicológicos , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares , Esquizofrenia/complicações , Esquizofrenia/genética
9.
Int J Mol Sci ; 22(23)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34884503

RESUMO

Individual differences in coping with stress may determine either a vulnerable or resilient phenotype. Therefore, it is important to better understand the biology underlying the behavioral phenotype. We assessed whether individual behavioral phenotype to acute stress is related with the hippocampal expression of glucocorticoid receptor (GR), Nurr1, interleukin-1 beta (IL-1ß) or brain-derived neurotrophic factor (BDNF). Wistar male rats were exposed to forced swimming for 15 min and sacrificed at different times. Behavioral response was analyzed, and it was compared with the gene and protein expression of GR, Nurr1, IL-1ß and BDNF in the hippocampus for each time point. Behavioral phenotyping showed a group with high immobility (vulnerable) while another had low immobility (resilient). No significant differences were found in the Nurr1, IL-1ß and BDNF mRNA levels between resilient and vulnerable rats at different recovery times except for Nr3c1 (gene for GR). However, exposure to stress caused significantly higher levels of GR, Nurr1 and IL-1ß proteins of vulnerable compared to resilient rats. This variability of behavioral phenotypes is associated with a differential molecular response to stress that involves GR, Nurr1, and IL-1ß as mediators in coping with stress. This contributes to identifying biomarkers of susceptibility to stress.


Assuntos
Comportamento Animal/fisiologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hipocampo/metabolismo , Interleucina-1beta/metabolismo , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Receptores de Glucocorticoides/metabolismo , Estresse Psicológico , Natação , Adaptação Psicológica , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Modelos Animais de Doenças , Feminino , Interleucina-1beta/genética , Masculino , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Receptores de Glucocorticoides/genética
10.
J Biol Chem ; 294(9): 3012-3023, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30563839

RESUMO

Mast cells (MCs) participate in allergy, inflammation, and defense against pathogens. They release multiple immune mediators via exocytosis, a process that requires SNARE proteins, including syntaxins (Stxs). The identity of the Stxs involved in MC exocytosis remains controversial. Here, we studied the roles of Stx3 and -4 in fully developed MCs from conditional knockout mice by electrophysiology and EM, and found that Stx3, and not Stx4, is crucial for MC exocytosis. The main defect seen in Stx3-deficient MCs was their inability to engage multigranular compound exocytosis, while leaving most single-vesicle fusion events intact. We used this defect to show that this form of exocytosis is not only required to accelerate MC degranulation but also essential to achieve full degranulation. The exocytic defect was severe but not absolute, indicating that an Stx other than Stx3 and -4 is also required for exocytosis in MCs. The removal of Stx3 affected only regulated exocytosis, leaving other MC effector responses intact, including the secretion of cytokines via constitutive exocytosis. Our in vivo model of passive systemic anaphylaxis showed that the residual exocytic function of Stx3-deficient MCs was sufficient to drive a full anaphylactic response in mice.


Assuntos
Exocitose , Mastócitos/citologia , Proteínas Qa-SNARE/metabolismo , Animais , Contagem de Células , Degranulação Celular , Diferenciação Celular , Técnicas de Inativação de Genes , Cinética , Camundongos , Proteínas Qa-SNARE/deficiência , Proteínas Qa-SNARE/genética
11.
J Transl Med ; 18(1): 1, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31900168

RESUMO

The present review aimed to discuss contemporary scientific literature involving differences between the tumor microenvironment (TME) in melanoma, lung cancer, and breast cancer in their primary site and TME in brain metastases (BM). TME plays a fundamental role in the behavior of cancer. In the process of carcinogenesis, cells such as fibroblasts, macrophages, endothelial cells, natural killer cells, and other cells can perpetuate and progress carcinogenesis via the secretion of molecules. Oxygen concentration, growth factors, and receptors in TME initiate angiogenesis and are examples of the importance of microenvironmental conditions in the performance of neoplastic cells. The most frequent malignant brain tumors are metastatic in origin and primarily originate from lung cancer, breast cancer, and melanoma. Metastatic cancer cells have to adhere to and penetrate the blood-brain barrier (BBB). After traversing BBB, these cells have to survive by producing various cytokines, chemokines, and mediators to modify their new TME. The microenvironment of these metastases is currently being studied owing to the discovery of new therapeutic targets. In these three types of tumors, treatment is more effective in the primary tumor than in BM due to several factors, including BBB. Understanding the differences in the characteristics of the microenvironment surrounding the primary tumor and their respective metastasis might help improve strategies to comprehend cancer.


Assuntos
Neoplasias Encefálicas , Microambiente Tumoral , Carcinogênese , Células Endoteliais , Humanos , Neovascularização Patológica
12.
Molecules ; 26(1)2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33375633

RESUMO

An evaluation of antioxidant and anticancer activity was screened in Leptocarpha rivularis DC flower extracts using four solvents (n-hexane (Hex), dichloromethane (DCM), ethyl acetate (AcOEt), and ethanol (EtOH)). Extracts were compared for total extract flavonoids and phenol contents, antioxidant activity (2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), ferric reducing antioxidant potential (FRAP), total reactive antioxidant properties (TRAP) and oxygen radical absorbance capacity (ORAC)) across a determined value of reduced/oxidized glutathione (GSH/GSSG), and cell viability (the sulforhodamine B (SRB) assay). The most active extracts were analyzed by chromatographic analysis (GC/MS) and tested for apoptotic pathways. Extracts from Hex, DCM and AcOEt reduced cell viability, caused changes in cell morphology, affected mitochondrial membrane permeability, and induced caspase activation in tumor cell lines HT-29, PC-3, and MCF-7. These effects were generally less pronounced in the HEK-293 cell line (nontumor cells), indicating clear selectivity towards tumor cell lines. We attribute likely extract activity to the presence of sesquiterpene lactones, in combination with other components like steroids and flavonoids.


Assuntos
Antineoplásicos Fitogênicos/química , Asteraceae/química , Neoplasias/tratamento farmacológico , Extratos Vegetais/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Flavonoides/química , Flores/química , Células HEK293 , Humanos , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia
13.
J Biol Chem ; 293(1): 345-358, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29141910

RESUMO

Mast cells (MCs) are involved in host defenses against pathogens and inflammation. Stimulated MCs release substances stored in their granules via regulated exocytosis. In other cell types, Munc13 (mammalian homolog of Caenorhabditis elegans uncoordinated gene 13) proteins play essential roles in regulated exocytosis. Here, we found that MCs express Munc13-2 and -4, and we studied their roles using global and conditional knock-out (KO) mice. In a model of systemic anaphylaxis, we found no difference between WT and Munc13-2 KO mice, but global and MC-specific Munc13-4 KO mice developed less hypothermia. This protection correlated with lower plasma histamine levels and with histological evidence of defective MC degranulation but not with changes in MC development, distribution, numbers, or morphology. In vitro assays revealed that the defective response in Munc13-4-deficient MCs was limited to regulated exocytosis, leaving other MC secretory effector responses intact. Single cell capacitance measurements in MCs from mouse mutants differing in Munc13-4 expression levels in their MCs revealed that as levels of Munc13-4 decrease, the rate of exocytosis declines first, and then the total amount of exocytosis decreases. A requirement for Munc13-2 in MC exocytosis was revealed only in the absence of Munc13-4. Electrophysiology and EM studies uncovered that the number of multigranular compound events (i.e. granule-to-granule homotypic fusion) was severely reduced in the absence of Munc13-4. We conclude that although Munc13-2 plays a minor role, Munc13-4 is essential for regulated exocytosis in MCs, and that this MC effector response is required for a full anaphylactic response.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Anafilaxia , Animais , Modelos Animais de Doenças , Exocitose/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Mastócitos/metabolismo , Mastócitos/fisiologia , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Isoformas de Proteínas , Transporte Proteico
14.
BMC Cancer ; 18(1): 928, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30257666

RESUMO

BACKGROUND: Cancer stem cells (CSC) are characterized by deregulated self-renewal, tumorigenicity, metastatic potential, aberrant stemness signaling pathways, resistance to conventional therapy, and the ability to give rise to a progeny of proliferating cells that constitute the bulk of tumors. Targeting CSC will provide novel treatments for cancer. Different investigations have focused on developing complementary approaches that involve natural compounds that decrease chemo-resistance and reduce the side effects of conventional therapies. Since, it has been reported that molecular iodine (I2) exhibits antineoplastic effects and decreases tumor progression in some cancer models, we evaluated the potential effect of I2 on cell cultures enriched in cervical cancer stem-like cells. METHODS: HeLa and SiHa cervical cancer cells were treated with 200uM I2 for 24 h. After time, cells were cultured in CSC-conditioned medium (cervospheres) and viability assays were performed. Following, tumorigenic capabilities in cervospheres treated with I2 were evaluated in NOD/SCID mice. HeLa monolayer cells untreated and their respective cervosphere cells treated or untreated with 200 µM of I2 for 24 h were xenotransplanted subcutaneously at different amounts and mice were monitored for at least 2 months. RESULTS: In the present study, monolayer and CSC-enriched cultures (cervospheres) from cervical cancer-derived cell lines, HeLa and SiHa, showed that 200uM I2 supplementation inhibits proliferation of both and decreased their tumorigenic capacity, in vivo. This antineoplastic effect of I2 was accompanied by diminished expression of stemness markers including CD49f, CK17, OCT-4, NANOG, SOX2, and KLF4, as well as increased expression and activation of PPARγ receptors. CONCLUSIONS: All this data led us to suggest a clinical potential use of I2 for targeting CSC and improve current treatments against cervical cancer.


Assuntos
Antineoplásicos/administração & dosagem , Iodo/administração & dosagem , Células-Tronco Neoplásicas/efeitos dos fármacos , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Iodo/farmacologia , Fator 4 Semelhante a Kruppel , Camundongos , Células-Tronco Neoplásicas/metabolismo , Neoplasias do Colo do Útero/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Int J Mol Sci ; 19(7)2018 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-29932118

RESUMO

The alteration of glucose metabolism is one of the first biochemical characteristics associated with cancer cells since most of these cells increase glucose consumption and glycolytic rates even in the presence of oxygen, which has been called “aerobic glycolysis" or the Warburg effect. Human papillomavirus (HPV) is associated with approximately 5% of all human cancers worldwide, principally to cervical cancer. E6 and E7 are the main viral oncoproteins which are required to preserve the malignant phenotype. These viral proteins regulate the cell cycle through their interaction with tumor suppressor proteins p53 and pRB, respectively. Together with the viral proteins E5 and E2, E6 and E7 can favor the Warburg effect and contribute to radio- and chemoresistance through the increase in the activity of glycolytic enzymes, as well as the inhibition of the Krebs cycle and the respiratory chain. These processes lead to a fast production of ATP obtained by Warburg, which could help satisfy the high energy demands of cancer cells during proliferation. In this way HPV proteins could promote cancer hallmarks. However, it is also possible that during an early HPV infection, the Warburg effect could help in the achievement of an efficient viral replication.


Assuntos
Metabolismo Energético , Proteínas Oncogênicas Virais/metabolismo , Papillomaviridae/metabolismo , Infecções por Papillomavirus/metabolismo , Neoplasias do Colo do Útero/metabolismo , Feminino , Glicólise , Interações Hospedeiro-Patógeno , Humanos , Modelos Biológicos , Proteínas Oncogênicas Virais/genética , Papillomaviridae/genética , Papillomaviridae/fisiologia , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia
16.
Stress ; 19(5): 506-15, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27219004

RESUMO

Depending on genetic predisposition, prenatal stress may result in vulnerability or resilience to develop psychiatric disorders in adulthood. Nurr1 is an immediate early gene, important in the brain for the stress response. We tested the hypothesis that prenatal stress and the decrease of hippocampal Nurr1 alter offspring behavioral responses in the forced swimming test (FST). Pregnant Wistar rats were exposed to restraint stress (45 min, thrice daily) from gestation day 14. Prenatally stressed (PS) and non-prenatally stressed (NPS) male offspring were treated bilaterally with a Nurr1 antisense oligodeoxynucleotide (ODN; or control) into the hippocampus at 97 d of age. After 1 h, the rats were exposed to the FST (acute stressor) to analyze their behavioral responses. Thirty minutes after the FST, we analyzed the gene expression of Nurr1, Bdnf and Nr3c1 (genes for Nurr1, brain-derived neurotrophic factor (BDNF) and glucocorticoid receptor (GR), respectively) in the hippocampus, prefrontal cortex (PFC) and hypothalamus. Results showed that the decrease of hippocampal Nurr1 after the antisense ODN in adult NPS rats induces immobility (indicating depressive-like behavior). The PS adult rats, including the group with decreased hippocampal Nurr1, presented low immobility in the FST. This low immobility was concordant with maintenance of Nurr1 and Bdnf expression levels in the three analyzed brain regions; Nr3c1 gene expression was also maintained in the PFC and hypothalamus. These findings suggest that Nurr1 and associated genes could participate in the brain modifications induced by prenatal stress, allowing active coping (resilience) with acute stress in adulthood.


Assuntos
Adaptação Psicológica/fisiologia , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Efeitos Tardios da Exposição Pré-Natal/genética , Estresse Psicológico/genética , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Feminino , Expressão Gênica , Hipocampo/metabolismo , Hipotálamo/metabolismo , Masculino , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Córtex Pré-Frontal/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/psicologia , Ratos , Ratos Wistar , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Restrição Física , Estresse Psicológico/metabolismo , Estresse Psicológico/psicologia , Natação/psicologia
17.
Rev Biol Trop ; 64(1): 363-76, 2016 03.
Artigo em Espanhol | MEDLINE | ID: mdl-28862825

RESUMO

The distribution and abundance of species of Trochillidae family is usually influenced by the flowering and phenology of plants used as a feeding source, mainly in primary forest, so that changes in vegetation cover could impact their populations. We analyzed and characterized the geographical distribution and habitat for 22 species of resident hummingbirds in the state of Guerrero using the vegetation and the land use map of INEGI Series IV (2007-2010). Distribution models were generated with the Genetic Algorithm for Rule Set Production (GARP), using historical records of scientific collections and fieldwork (2001-2009), in combination with climatic and topographic variables. Of the 22 modeled species, six are endemic to Mexico, the same number of species found in a risk category. The highest concentration with regards to richness (14-20 species), endemism (5-6 species) and number of threatened species of hummingbirds (5-6 species) occurred in the biotic province of Sierra Madre del Sur. However, the potential distribution of most of the hummingbirds occurred in disturbed sites or agroecosystems, as a result of changes in land-use. For Campylopterus hemileucurus, Lamprolaima rhami and Heliomaster longisrostris, their potential distribution was highest in areas of primary vegetation. Areas of high hummingbirds presence do not coincide with the Important Bird Areas proposed for bird conservation in Guerrero, considering that, despite its diversity and its extreme popularity, from the conservation perspective hummingbirds have received relatively little attention.


Assuntos
Distribuição Animal , Biodiversidade , Aves/classificação , Ecossistema , Animais , Conservação dos Recursos Naturais , México , Densidade Demográfica , Estações do Ano
18.
Clin Endocrinol (Oxf) ; 83(2): 229-35, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25565002

RESUMO

OBJECTIVE: Follistatin (FST) is a regulator of the biological activity of activin A (Act A), binding and blocking it, which could contribute to the modulation of its pro-inflammatory activity during pregnancy. We sought to investigate, in this nested case-control study, FST serum levels during normal pregnancy and correlate it with the FST profile in preeclamptic pregnant women, normal pregnant women followed 3 months postpartum and eumenorrheic nonpregnant women throughout the menstrual cycle. SUBJECTS AND METHODS: Follistatin serum levels determined by ELISA, biochemical and anthropometric variables were measured in normal pregnant (n = 28) and preeclamptic (n = 20) women during three periods of gestation. In addition, FST serum levels were measured in a subset of normal pregnant women (n = 13) followed 3 months postpartum and in eumenorrheic nonpregnant women (n = 20) during the follicular and luteal phases of the menstrual cycle. RESULTS: Follistatin serum levels in the eumenorrheic nonpregnant and postpartum group were significantly lower when compared to levels throughout gestation (P < 0·01). Serum FST levels increased in each period of pregnancy analysed, being significantly higher towards the end of gestation (P < 0·01). FST levels were lower in late pregnancy in preeclamptic women compared to normal pregnant women (P < 0·05). Finally, FST levels were higher in the luteal phase when compared with the follicular phase of the menstrual cycle (P < 0·05). CONCLUSIONS: These analyses would permit the consideration that changes in FST levels during pregnancy contribute to the control of the Act A system.


Assuntos
Folistatina/sangue , Pré-Eclâmpsia/sangue , Gravidez/sangue , Adolescente , Adulto , Antropometria , Pressão Sanguínea , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Fase Folicular/sangue , Humanos , Estudos Longitudinais , Fase Luteal/sangue , Período Pós-Parto , Reprodutibilidade dos Testes , Adulto Jovem
19.
Cytokine ; 75(1): 136-41, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26144294

RESUMO

Omentin-1 is an adipocytokine with anti-inflammatory activity that has been associated with different metabolic disorders. The aim of this study is to investigate the serum profiles of omentin-1 throughout human and rat pregnancy. Serum omentin-1 levels were determined by ELISA in a prospective cohort study of healthy pregnant women (n=40) during the three trimesters of pregnancy and in twenty healthy non-pregnant women during the follicular and luteal phase of the menstrual cycle. In addition, serum omentin-1 levels were measured in rats during different periods of pregnancy (gestational days 8, 12, 16, 19, and 21) and in an age-matched control (virgin) group of rats (n=12rats/group). Finally, immunohistochemistry was used to demonstrate the presence of omentin-1 protein in human and rat placenta. Omentin-1 immunoreactivity was detected in cytotrophoblasts, syncytiotrophoblasts, sparse Hofbauer cells, and endothelial cells of the stem villi of human placenta. Additionally, it was detected in the labyrinthine trophoblast and yolk sac layer of the rat placenta. Human and rat serum omentin-1 levels were significantly lower in the late gestational period when compared with the non-pregnant women and virgin rats (p<0.05). Serum omentin-1 changes were not significant throughout the gestation in both species (p>0.05). Human serum omentin-1 levels have an inverse relationship with triglyceride levels during pregnancy. Our findings have not determined the exact role of omentin-1 during pregnancy, concerning the metabolic control of triglycerides and other energy sources. Whether omentin-1 decrease implies a regulatory function is still not clear. Further studies are needed to address this issue and determine the role of omentin-1 in metabolic adaptations during normal human and rat pregnancy.


Assuntos
Citocinas/sangue , Regulação da Expressão Gênica no Desenvolvimento , Lectinas/sangue , Adulto , Animais , Vilosidades Coriônicas/metabolismo , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Proteínas Ligadas por GPI/sangue , Humanos , Imuno-Histoquímica , Gravidez , Prenhez , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Triglicerídeos/metabolismo , Trofoblastos/metabolismo , Saco Vitelino/metabolismo , Adulto Jovem
20.
Clin Endocrinol (Oxf) ; 81(1): 141-51, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24372023

RESUMO

OBJECTIVE: Pregnancy is characterized by several metabolic changes that promote fat gain and later onset of insulin resistance. As Brain-derived neurotrophic factor (BDNF) decreases hyperglycaemia and hyperphagia, we aimed to investigate the potential role of placental and circulating BDNF levels in these pregnancy-related metabolic changes in rats and humans. DESIGN AND METHODS: We identified the mRNA and protein expression of placental BDNF and its receptor TrkB using real-time PCR, Western blot and immunohistochemical approaches in both rat and humans. Serum BDNF was measured by ELISA. We also did a longitudinal prospective cohort study in 42 pregnant women to assess BDNF levels and correlations with other metabolic parameters. RESULTS: We found that BDNF and TrkB are expressed in both rat and human placenta. In rat, both placental mRNA and serum levels are increased throughout pregnancy, whereas their protein levels are significantly decreased at the end of gestation. Serum BDNF levels in pregnant women are significantly lower in the first trimester when compared to the second and third trimester (P < 0·0148, P < 0·0012, respectively). Serum BDNF levels were negatively correlated with gestational age at birth and fasting glucose levels. CONCLUSION: Our findings suggest that both BDNF and its receptor TrkB are expressed in rodent and human placenta being regulated during pregnancy. Taken together, these findings support a role of BDNF in the regulation of several metabolic functions during pregnancy.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/sangue , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Placenta/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Feminino , Humanos , Imunoquímica , Gravidez , RNA Mensageiro , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Receptor trkB/sangue , Receptor trkB/genética , Receptor trkB/metabolismo
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