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1.
Inflamm Res ; 73(9): 1459-1476, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38965133

RESUMEN

OBJECTIVE: We aimed to broaden our understanding of a potential interaction between B1R and TLR4, considering earlier studies suggesting that lipopolysaccharide (LPS) may trigger B1R stimulation. METHODS: We assessed the impact of DBK and LPS on the membrane potential of thoracic aortas from C57BL/6, B1R, or TLR4 knockout mice. Additionally, we examined the staining patterns of these receptors in the thoracic aortas of C57BL/6 and in endothelial cells (HBMEC). RESULTS: DBK does not affect the resting membrane potential of aortic rings in C57BL/6 mice, but it hyperpolarizes preparations in B1KO and TLR4KO mice. The hyperpolarization mechanism in B1KO mice involves B2R, and the TLR4KO response is independent of cytoplasmic calcium influx but relies on potassium channels. Conversely, LPS hyperpolarizes thoracic aorta rings in both C57BL/6 and B1KO mice, with the response unaffected by a B1R antagonist. Interestingly, the absence of B1R alters the LPS response to potassium channels. These activities are independent of nitric oxide synthase (NOS). While exposure to DBK and LPS does not alter B1R and TLR4 mRNA expression, treatment with these agonists increases B1R staining in endothelial cells of thoracic aortic rings and modifies the staining pattern of B1R and TLR4 in endothelial cells. Proximity ligation assay suggests a interaction between the receptors. CONCLUSION: Our findings provide additional support for a putative connection between B1R and TLR4 signaling. Given the involvement of these receptors and their agonists in inflammation, it suggests that drugs and therapies targeting their effects could be promising therapeutic avenues worth exploring.


Asunto(s)
Aorta Torácica , Células Endoteliales , Lipopolisacáridos , Ratones Endogámicos C57BL , Ratones Noqueados , Receptor de Bradiquinina B1 , Receptor Toll-Like 4 , Animales , Masculino , Ratones , Aorta Torácica/metabolismo , Bradiquinina/farmacología , Bradiquinina/metabolismo , Células Cultivadas , Células Endoteliales/metabolismo , Inflamación/metabolismo , Lipopolisacáridos/farmacología , Potenciales de la Membrana/efectos de los fármacos , Receptor de Bradiquinina B1/metabolismo , Receptor de Bradiquinina B1/genética , Receptor Toll-Like 4/metabolismo , Receptor Toll-Like 4/genética , Femenino
2.
Syst Biol ; 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38085256

RESUMEN

Time-scaled phylogenetic trees are an ultimate goal of evolutionary biology and a necessary ingredient in comparative studies. The accumulation of genomic data has resolved the tree of life to a great extent, yet timing evolutionary events remains challenging if not impossible without external information such as fossil ages and morphological characters. Methods for incorporating morphology in tree estimation have lagged behind their molecular counterparts, especially in the case of continuous characters. Despite recent advances, such tools are still direly needed as we approach the limits of what molecules can teach us. Here, we implement a suite of state-of-the-art methods for leveraging continuous morphology in phylogenetics, and by conducting extensive simulation studies we thoroughly validate and explore our methods' properties. While retaining model generality and scalability, we make it possible to estimate absolute and relative divergence times from multiple continuous characters while accounting for uncertainty. We compile and analyze one of the most data-type diverse data sets to date, comprised of contemporaneous and ancient molecular sequences, and discrete and continuous characters from living and extinct Carnivora taxa. We conclude by synthesizing lessons about our method's behavior, and suggest future research venues.

3.
PLoS Comput Biol ; 19(7): e1011226, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37463154

RESUMEN

Phylogenetic models have become increasingly complex, and phylogenetic data sets have expanded in both size and richness. However, current inference tools lack a model specification language that can concisely describe a complete phylogenetic analysis while remaining independent of implementation details. We introduce a new lightweight and concise model specification language, 'LPhy', which is designed to be both human and machine-readable. A graphical user interface accompanies 'LPhy', allowing users to build models, simulate data, and create natural language narratives describing the models. These narratives can serve as the foundation for manuscript method sections. Additionally, we present a command-line interface for converting LPhy-specified models into analysis specification files (in XML format) compatible with the BEAST2 software platform. Collectively, these tools aim to enhance the clarity of descriptions and reporting of probabilistic models in phylogenetic studies, ultimately promoting reproducibility of results.


Asunto(s)
Lenguaje , Programas Informáticos , Humanos , Filogenia , Reproducibilidad de los Resultados , Modelos Estadísticos , Interfaz Usuario-Computador
4.
Diseases ; 11(2)2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37366874

RESUMEN

Glioblastoma is a highly aggressive brain tumor with a poor prognosis. Recent studies have suggested that mechanobiology, the study of how physical forces influence cellular behavior, plays an important role in glioblastoma progression. Several signaling pathways, molecules, and effectors, such as focal adhesions, stretch-activated ion channels, or membrane tension variations, have been studied in this regard. Also investigated are YAP/TAZ, downstream effectors of the Hippo pathway, which is a key regulator of cell proliferation and differentiation. In glioblastoma, YAP/TAZ have been shown to promote tumor growth and invasion by regulating genes involved in cell adhesion, migration, and extracellular matrix remodeling. YAP/TAZ can be activated by mechanical cues such as cell stiffness, matrix rigidity, and cell shape changes, which are all altered in the tumor microenvironment. Furthermore, YAP/TAZ have been shown to crosstalk with other signaling pathways, such as AKT, mTOR, and WNT, which are dysregulated in glioblastoma. Thus, understanding the role of mechanobiology and YAP/TAZ in glioblastoma progression could provide new insights into the development of novel therapeutic strategies. Targeting YAP/TAZ and mechanotransduction pathways in glioblastoma may offer a promising approach to treating this deadly disease.

5.
bioRxiv ; 2023 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-38168278

RESUMEN

We introduce PhyloJunction, a computational framework designed to facilitate the prototyping, testing, and characterization of evolutionary models. PhyloJunction is distributed as an open-source Python library that can be used to implement a variety of models, through its flexible graphical modeling architecture and dedicated model specification language. Model design and use are exposed to users via command-line and graphical interfaces, which integrate the steps of simulating, summarizing, and visualizing data. This paper describes the features of PhyloJunction - which include, but are not limited to, a general implementation of a popular family of phylogenetic diversification models - and, moving forward, how it may be expanded to not only include new models, but to also become a platform for conducting and teaching statistical learning.

6.
Int J Mol Sci ; 23(20)2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36292931

RESUMEN

The Wnt/ß-catenin signaling pathway dictates cell proliferation and differentiation during embryonic development and tissue homeostasis. Its deregulation is associated with many pathological conditions, including neurodegenerative disease, frequently downregulated. The lack of efficient treatment for these diseases, including Alzheimer's disease (AD), makes Wnt signaling an attractive target for therapies. Interestingly, novel Wnt signaling activating compounds are less frequently described than inhibitors, turning the quest for novel positive modulators even more appealing. In that sense, natural compounds are an outstanding source of potential drug leads. Here, we combine different experimental models, cell-based approaches, neuronal culture assays, and rodent behavior tests with Xenopus laevis phenotypic analysis to characterize quercitrin, a natural compound, as a novel Wnt signaling potentiator. We find that quercitrin potentiates the signaling in a concentration-dependent manner and increases the occurrence of the Xenopus secondary axis phenotype mediated by Xwnt8 injection. Using a GSK3 biosensor, we describe that quercitrin impairs GSK3 activity and increases phosphorylated GSK3ß S9 levels. Treatment with XAV939, an inhibitor downstream of GSK3, impairs the quercitrin-mediated effect. Next, we show that quercitrin potentiates the Wnt3a-synaptogenic effect in hippocampal neurons in culture, which is blocked by XAV939. Quercitrin treatment also rescues the hippocampal synapse loss induced by intracerebroventricular injection of amyloid-ß oligomers (AßO) in mice. Finally, quercitrin rescues AßO-mediated memory impairment, which is prevented by XAV939. Thus, our study uncovers a novel function for quercitrin as a Wnt/ß-catenin signaling potentiator, describes its mechanism of action, and opens new avenues for AD treatments.


Asunto(s)
Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Ratones , Animales , Vía de Señalización Wnt , Péptidos beta-Amiloides/farmacología , beta Catenina/metabolismo , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Enfermedad de Alzheimer/patología , Quercetina/farmacología , Quercetina/uso terapéutico
7.
Cancers (Basel) ; 14(13)2022 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-35804976

RESUMEN

Glioblastomas are considered the most common and aggressive primary brain tumor in adults, with an average of 15 months' survival rate. The treatment is surgery resection, followed by chemotherapy with temozolomide, and/or radiotherapy. Glioblastoma must have wild-type IDH gene and some characteristics, such as TERT promoter mutation, EGFR gene amplification, microvascular proliferation, among others. Glioblastomas have great heterogeneity at cellular and molecular levels, presenting distinct phenotypes and diversified molecular signatures in each tumor mass, making it difficult to define a specific therapeutic target. It is believed that the main responsibility for the emerge of these distinct patterns lies in subcellular populations of tumor stem cells, capable of tumor initiation and asymmetric division. Studies are now focused on understanding molecular mechanisms of chemoresistance, the tumor microenvironment, due to hypoxic and necrotic areas, cytoskeleton and extracellular matrix remodeling, and in controlling blood brain barrier permeabilization to improve drug delivery. Another promising therapeutic approach is the use of oncolytic viruses that are able to destroy specifically glioblastoma cells, preserving the neural tissue around the tumor. In this review, we summarize the main biological characteristics of glioblastoma and the cutting-edge therapeutic targets that are currently under study for promising new clinical trials.

8.
Virus Evol ; 7(2): veab052, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34527282

RESUMEN

New Zealand, Australia, Iceland, and Taiwan all saw success in controlling their first waves of Coronavirus Disease 2019 (COVID-19). As islands, they make excellent case studies for exploring the effects of international travel and human movement on the spread of COVID-19. We employed a range of robust phylodynamic methods and genome subsampling strategies to infer the epidemiological history of Severe acute respiratory syndrome coronavirus 2 in these four countries. We compared these results to transmission clusters identified by the New Zealand Ministry of Health by contact tracing strategies. We estimated the effective reproduction number of COVID-19 as 1-1.4 during early stages of the pandemic and show that it declined below 1 as human movement was restricted. We also showed that this disease was introduced many times into each country and that introductions slowed down markedly following the reduction of international travel in mid-March 2020. Finally, we confirmed that New Zealand transmission clusters identified via standard health surveillance strategies largely agree with those defined by genomic data. We have demonstrated how the use of genomic data and computational biology methods can assist health officials in characterising the epidemiology of viral epidemics and for contact tracing.

9.
Syst Biol ; 71(1): 208-220, 2021 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-34228807

RESUMEN

Evolutionary models account for either population- or species-level processes but usually not both. We introduce a new model, the FBD-MSC, which makes it possible for the first time to integrate both the genealogical and fossilization phenomena, by means of the multispecies coalescent (MSC) and the fossilized birth-death (FBD) processes. Using this model, we reconstruct the phylogeny representing all extant and many fossil Caninae, recovering both the relative and absolute time of speciation events. We quantify known inaccuracy issues with divergence time estimates using the popular strategy of concatenating molecular alignments and show that the FBD-MSC solves them. Our new integrative method and empirical results advance the paradigm and practice of probabilistic total evidence analyses in evolutionary biology.[Caninae; fossilized birth-death; molecular clock; multispecies coalescent; phylogenetics; species trees.].


Asunto(s)
Especiación Genética , Modelos Biológicos , Evolución Biológica , Fósiles , Filogenia
10.
Cancers (Basel) ; 13(8)2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33920762

RESUMEN

Head and neck squamous cell carcinomas (HNSCC) are among the most common and lethal tumors worldwide, occurring mostly in oral cavity, pharynx, and larynx tissues. The squamous epithelia homeostasis is supported by the extracellular matrix (ECM), and alterations in this compartment are crucial for cancer development and progression. Laminin is a fundamental component of ECM, where it represents one of the main components of basement membrane (BM), and data supporting its contribution to HNSCC genesis and progression has been vastly explored in oral cavity squamous cell carcinoma. Laminin subtypes 111 (LN-111) and 332 (LN-332) are the main isoforms associated with malignant transformation, contributing to proliferation, adhesion, migration, invasion, and metastasis, due to its involvement in the regulation of several pathways associated with HNSCC carcinogenesis, including the activation of the EGFR/MAPK signaling pathway. Therefore, it draws attention to the possibility that laminin may represent a convergence point in HNSCC natural history, and an attractive potential therapeutic target for these tumors.

11.
Signal Transduct Target Ther ; 6(1): 45, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33526777

RESUMEN

Lysophosphatidic acid (LPA) is an abundant bioactive phospholipid, with multiple functions both in development and in pathological conditions. Here, we review the literature about the differential signaling of LPA through its specific receptors, which makes this lipid a versatile signaling molecule. This differential signaling is important for understanding how this molecule can have such diverse effects during central nervous system development and angiogenesis; and also, how it can act as a powerful mediator of pathological conditions, such as neuropathic pain, neurodegenerative diseases, and cancer progression. Ultimately, we review the preclinical and clinical uses of Autotaxin, LPA, and its receptors as therapeutic targets, approaching the most recent data of promising molecules modulating both LPA production and signaling. This review aims to summarize the most update knowledge about the mechanisms of LPA production and signaling in order to understand its biological functions in the central nervous system both in health and disease.


Asunto(s)
Lisofosfolípidos/genética , Neovascularización Patológica/genética , Fosfolípidos/genética , Humanos , Lisofosfolípidos/metabolismo , Terapia Molecular Dirigida , Neovascularización Patológica/tratamiento farmacológico , Fosfolípidos/metabolismo , Hidrolasas Diéster Fosfóricas/genética , Hidrolasas Diéster Fosfóricas/uso terapéutico , Receptores del Ácido Lisofosfatídico/genética , Receptores del Ácido Lisofosfatídico/uso terapéutico , Transducción de Señal/genética
12.
J Neurochem ; 156(4): 499-512, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32438456

RESUMEN

Glioblastomas (GBMs) are highly aggressive primary brain tumors characterized by cellular heterogeneity, insensitivity to chemotherapy and poor patient survival. Lysophosphatidic acid (LPA) is a lysophospholipid that acts as a bioactive signaling molecule and plays important roles in diverse biological events during development and disease, including several cancer types. Microglial cells, the resident macrophages of the central nervous system, express high levels of Autotaxin (ATX,Enpp2), an enzyme that synthetizes LPA. Our study aimed to investigate the role of LPA on tumor growth and invasion in the context of microglia-GBM interaction. First, through bioinformatics studies, patient data analysis demonstrated that more aggressive GBM expressed higher levels of ENPP2, which was also associated with worse patient prognosis with proneural GBM. Using GBM-microglia co-culture system we then demonstrated that GBM secreted factors were able to increase LPA1 and ATX in microglia, which could be further enhanced by hypoxia. On the other hand, interaction with microglial cells also increased ATX expression in GBM. Furthermore, microglial-induced GBM proliferation and migration could be inhibited by pharmacological inhibition of LPA1 , suggesting that microglial-derived LPA could support tumor growth and invasion. Finally, increased LPA1 expression was observed in GBM comparing with other gliomas and could be also associated with worse patient survival. These results show for the first time a microglia-GBM interaction through the LPA pathway with relevant implications for tumor progression. A better understanding of this interaction can lead to the development of new therapeutic strategies setting LPA as a potential target for GBM treatment.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Movimiento Celular/fisiología , Glioblastoma/metabolismo , Lisofosfolípidos/metabolismo , Microglía/metabolismo , Receptores del Ácido Lisofosfatídico/biosíntesis , Animales , Neoplasias Encefálicas/patología , Proliferación Celular/fisiología , Células Cultivadas , Femenino , Glioblastoma/patología , Humanos , Masculino , Ratones , Microglía/patología
13.
Bioinformatics ; 36(22-23): 5516-5518, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33325502

RESUMEN

MOTIVATION: Genome sequencing projects have revealed frequent gains and losses of genes between species. Previous versions of our software, Computational Analysis of gene Family Evolution (CAFE), have allowed researchers to estimate parameters of gene gain and loss across a phylogenetic tree. However, the underlying model assumed that all gene families had the same rate of evolution, despite evidence suggesting a large amount of variation in rates among families. RESULTS: Here, we present CAFE 5, a completely re-written software package with numerous performance and user-interface enhancements over previous versions. These include improved support for multithreading, the explicit modeling of rate variation among families using gamma-distributed rate categories, and command-line arguments that preclude the use of accessory scripts. AVAILABILITY AND IMPLEMENTATION: CAFE 5 source code, documentation, test data and a detailed manual with examples are freely available at https://github.com/hahnlab/CAFE5/releases. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

14.
World Neurosurg ; 146: e537-e543, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33130134

RESUMEN

OBJECTIVE: The common fibular nerve (CFN) is the most frequently injured nerve in the lower limbs. Surgical management is necessary in approximately two thirds of patients and includes neurolysis, suture, graft repair, or nerve transfer. The distal sural nerve is the preferred donor for grafting, but it is not without complications and requires a second incision. We sought to study the surgical anatomy of the lateral sural cutaneous nerve (LSCN) with the aim of repairing CFN injuries through the same incision and as a potential source for grafting in other nerve injuries. METHODS: The popliteal fossa was dissected in 11 lower limbs of embalmed cadavers to study LSCN variations. Four patients with CFN injuries then underwent surgical repair by LSCN grafting using the same surgical approach. RESULTS: At the medial margin of the biceps femoris, the LSCN emerged from the CFN approximately 8.15 cm above the fibular head. The LSCN ran longitudinally to the long axis of the popliteal fossa, with an average of 3.2 cm medial to the fibular head. The mean LSCN length and diameter were 9.61 cm and 3.6 mm, respectively. The LSCN could be harvested in all patients for grafting. The mean graft length was 4.4 cm. Motor function was consistently recovered for foot eversion but was recovered to a lesser extent for dorsiflexion and toe extension. All patients recovered sensitive function (75% of S3). Hypoesthesia was recognized at the calf. CONCLUSIONS: LSCN harvest is a viable alternative for nerve grafting, especially for repairing short CFN injuries, thereby avoiding the need for a second incision.


Asunto(s)
Peroné/cirugía , Pierna/cirugía , Transferencia de Nervios , Nervio Peroneo/cirugía , Nervio Sural/cirugía , Adolescente , Adulto , Estudios de Factibilidad , Peroné/inervación , Humanos , Pierna/fisiopatología , Extremidad Inferior/cirugía , Masculino , Procedimientos Neuroquirúrgicos , Neuropatías Peroneas/cirugía , Procedimientos de Cirugía Plástica/métodos , Adulto Joven
15.
Nat Commun ; 11(1): 6351, 2020 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-33311501

RESUMEN

New Zealand, a geographically remote Pacific island with easily sealable borders, implemented a nationwide 'lockdown' of all non-essential services to curb the spread of COVID-19. Here, we generate 649 SARS-CoV-2 genome sequences from infected patients in New Zealand with samples collected during the 'first wave', representing 56% of all confirmed cases in this time period. Despite its remoteness, the viruses imported into New Zealand represented nearly all of the genomic diversity sequenced from the global virus population. These data helped to quantify the effectiveness of public health interventions. For example, the effective reproductive number, Re of New Zealand's largest cluster decreased from 7 to 0.2 within the first week of lockdown. Similarly, only 19% of virus introductions into New Zealand resulted in ongoing transmission of more than one additional case. Overall, these results demonstrate the utility of genomic pathogen surveillance to inform public health and disease mitigation.


Asunto(s)
COVID-19/epidemiología , Genoma Viral/genética , Genómica/métodos , SARS-CoV-2/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/virología , Niño , Preescolar , Femenino , Geografía , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Pandemias , Filogenia , SARS-CoV-2/clasificación , SARS-CoV-2/fisiología , Secuenciación Completa del Genoma/métodos , Adulto Joven
16.
Rev. bras. anal. clin ; 52(3): 228-234, 20200930. tab, ilus
Artículo en Portugués | LILACS | ID: biblio-1255088

RESUMEN

Objetivo: Devido à atual resistência bacteriana aos antimicrobianos e à necessidade de buscar novas substâncias com essa atividade, principalmente em produtos naturais, esse trabalho objetivou avaliar e comparar o potencial antibacteriano de extratos de folhas da planta Eugenia brasiliensis, ainda pouco estudada, obtidas por coletas sazonais. Métodos: As coletas foram realizadas trimestralmente no Jardim Botânico do RJ (JBRJ) e os extratos etanólicos preparados com o pó das folhas secas. Foram utilizadas cepas de referência ATCC (American Type Culture Collection) Gram positivas de Staphylococcus aureus: 25.923 (Beta Lactamase -) e 29.213 (Beta Lactamase +), e duas Gram negativas, Escherichia coli (28.922) e Pseudomonas aeruginosa (27.853). A técnica de escolha foi a microdiluição em placa de 96 poços, pois permite avaliar a concentração inibitória mínima (CIM) e posteriormente a concentração bactericida mínima (CBM). Resultados: A melhor atividade antibacteriana (1 mg/mL) foi identificada nos extratos obtidos nos meses mais quentes (menores CIM para bactérias Gram positivas). A CBM foi compatível com a CIM na maioria das estações/cepas bacterianas, indicando possível atividade bactericida dos extratos. Conclusão: A pesquisa demonstrou uma atividade antibacteriana promissora para Gram positivos e existência de variação sazonal, sugerindo um bom potencial para o uso de E. brasiliensis como antimicrobiano. Os resultados também indicam que, no futuro, outros estudos devem ser realizados, como a prospecção química destes extratos.


Objective: Due to the current bacterial resistance to antimicrobials and the need to search for new substances with this activity, mainly in natural products, this work aimed to evaluate and compare the antibacterial potential of Eugenia brasiliensis leaf extracts, still little studied, obtained by seasonal collections. Methods: Leaf collections were made quarterly at the Jardim Botânico do RJ (JBRJ) and ethanol extracts prepared with dry leaf powder. Reference strains ATCC (American Type Culture Collection) Gram positive from Staphylococcus aureus were used: 25923 (Beta Lactamase -) and 29213 (Beta Lactamase +), and two Gram negative strains, Escherichia coli (28.922) and Pseudomonas aeruginosa (27.853). The technique of choice was microdilution in a 96-well plate, as it allows the assessment of the minimum inhibitory concentration (MIC) and subsequently the minimum bactericidal concentration (CBM). Results: The best antibacterial activity (1 mg/mL) was identified in the extracts obtained in the warmer months (lower MICs for Gram positive bacteria). CBM was compatible with MIC in most seasons/ bacterial strains, indicating possible bactericidal activity of the extracts. Conclusion: The research demonstrated a promising antibacterial activity for Gram positive and seasonal variation, suggesting a good potential for the use of E.brasiliensis as an antimicrobial. The results also indicate that in the future, other studies should be carried out, such as the chemical prospecting of these extracts.


Asunto(s)
Extractos Vegetales , Farmacorresistencia Bacteriana , Eugenia , Antiinfecciosos
17.
Sci Rep ; 10(1): 11681, 2020 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-32669593

RESUMEN

More than 94% of colorectal cancer cases have mutations in one or more Wnt/ß-catenin signaling pathway components. Inactivating mutations in APC or activating mutations in ß-catenin (CTNNB1) lead to signaling overactivation and subsequent intestinal hyperplasia. Numerous classes of medicines derived from synthetic or natural small molecules, including alkaloids, have benefited the treatment of different diseases, including cancer, Piperine is a true alkaloid, derived from lysine, responsible for the spicy taste of black pepper (Piper nigrum) and long pepper (Piper longum). Studies have shown that piperine has a wide range of pharmacological properties; however, piperine molecular mechanisms of action are still not fully understood. By using Wnt/ß-catenin pathway epistasis experiment we show that piperine inhibits the canonical Wnt pathway induced by overexpression of ß-catenin, ß-catenin S33A or dnTCF4 VP16, while also suppressing ß-catenin nuclear localization in HCT116 cell line. Additionally, piperine impairs cell proliferation and migration in HCT116, SW480 and DLD-1 colorectal tumor cell lines, while not affecting the non-tumoral cell line IEC-6. In summary, piperine inhibits the canonical Wnt signaling pathway and displays anti-cancer effects on colorectal cancer cell lines.


Asunto(s)
Alcaloides/farmacología , Antineoplásicos Fitogénicos/farmacología , Benzodioxoles/farmacología , Regulación Neoplásica de la Expresión Génica , Piperidinas/farmacología , Alcamidas Poliinsaturadas/farmacología , Vía de Señalización Wnt/efectos de los fármacos , Proteína Wnt3A/antagonistas & inhibidores , beta Catenina/antagonistas & inhibidores , Alcaloides/aislamiento & purificación , Antineoplásicos Fitogénicos/aislamiento & purificación , Benzodioxoles/aislamiento & purificación , Ciclo Celular/efectos de los fármacos , Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células HCT116 , Células HEK293 , Humanos , Piper nigrum/química , Piperidinas/aislamiento & purificación , Alcamidas Poliinsaturadas/aislamiento & purificación , Factores de Transcripción TCF/genética , Factores de Transcripción TCF/metabolismo , Vía de Señalización Wnt/genética , Proteína Wnt3A/genética , Proteína Wnt3A/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
18.
Cancers (Basel) ; 11(12)2019 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-31817828

RESUMEN

The deregulation of the Wnt/ß-catenin signaling pathway is a central event in colorectal cancer progression, thus a promising target for drug development. Many natural compounds, such as flavonoids, have been described as Wnt/ß-catenin inhibitors and consequently modulate important biological processes like inflammation, redox balance, cancer promotion and progress, as well as cancer cell death. In this context, we identified the chalcone lonchocarpin isolated from Lonchocarpus sericeus as a Wnt/ß-catenin pathway inhibitor, both in vitro and in vivo. Lonchocarpin impairs ß-catenin nuclear localization and also inhibits the constitutively active form of TCF4, dnTCF4-VP16. Xenopus laevis embryology assays suggest that lonchocarpin acts at the transcriptional level. Additionally, we described lonchocarpin inhibitory effects on cell migration and cell proliferation on HCT116, SW480, and DLD-1 colorectal cancer cell lines, without any detectable effects on the non-tumoral intestinal cell line IEC-6. Moreover, lonchocarpin reduces tumor proliferation on the colorectal cancer AOM/DSS mice model. Taken together, our results support lonchocarpin as a novel Wnt/ß-catenin inhibitor compound that impairs colorectal cancer cell growth in vitro and in vivo.

19.
Eur J Dent ; 13(2): 222-228, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31574541

RESUMEN

OBJECTIVES: The aim of this study was to evaluate the bonding strength of self-adhesive luting cement to zirconia under different surface treatments. MATERIALS AND METHODS: Thirty-two zirconia samples were randomly divided into eight experimental groups based on the surface treatment employed (Control: no surface treatment; PMM: wear with diamond bur; JAT: blasting with glass beads; PMA: wear with a medium-roughness milling machine; Primer: primer application on the surface without treatment; PMM +Primer: PMM treatment plus primer application; JAT+Primer: JAT treatment plus primer application; and PMA+Primer: PMA treatment plus primer application). Cement cylinders were built on the ceramic surfaces, and the groups were subdivided according to the storage time employed (i.e., 24 hours or 60 days). After storage, the samples were subjected to microshear testing. STATISTICAL ANALYSIS: The Kruskal-Wallis test followed by the Dunn test was employed for comparison between the groups (p < 0.05). RESULTS: The PMM group yielded the optimal results and the mean values increased after both storage times following the primer application. The Control, PMA, and JAT groups gave similar results after 24 hours, while the JAT group gave superior results following primer application over this storage time. After 60 days of storage, all groups gave improved results following chemical treatment with a primer. CONCLUSION: It was concluded that mechanical preparation using the diamond bur followed by primer application significantly improved the bond strength between the ceramic and the luting cement.

20.
Exp Cell Res ; 383(1): 111499, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31302030

RESUMEN

CUB domains are most exclusively found in secreted proteins and in a few transmembrane proteins. These domains are approximately 110 amino acids long and have four conserved cysteines that form a ß-sandwich fold. CUB domains proteins are involved in a wide range of biological functions. We have shown that CUB domains from Tolloid/BMP1 can bind BMP4 and block BMP signaling in the developing frog embryo. CUB domain-containing protein 1 (CDCP1) is one of the few transmembrane glycoprotein that contains three extracellular CUB domains and regulates anchorage-independent growth and cancer cell migration through activation of Src kinases. In the extracellular space, only a few proteins were found to interact with CDCP1 and at the moment no ligand was found. We demonstrate by using real time protein interaction on BIAcore chip that CDCP1 CUB domains bind directly to TGF-ß1 and BMP4. CDCP1 enhances TGF-ß1 signaling reporter activity and phosphorylated Smad2 levels but does not modulate BMP signaling pathway. CDCP1 actions on TGF-ß/Smad2 signaling are dependent on Smad2 and TGFRI and do not require Src or PKCδ binding. Our findings uncover a new co-receptor for TGF-ß1 and bring up new questions on whether CDCP1 cooperates with TGF-ß1 to promote cancer progression.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Moléculas de Adhesión Celular/metabolismo , Proteína Smad2/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Familia-src Quinasas/metabolismo , Células HeLa , Humanos , Fosforilación
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