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1.
Artigo em Inglês | MEDLINE | ID: mdl-36673798

RESUMO

Background: Explosive strength is essential for rhythmic gymnasts' performance. It has been suggested that core stability (CS) and plyometric training can enhance athletes' explosive strength. Nevertheless, there is some uncertainty about the effects of integrated core and plyometric training (CPT) programs on rhythmic gymnastics (RG) performances. Purpose: to evaluate the effects of an integrated functional CPT program on young rhythmic gymnasts' explosive strength and jump/leap performance. Method: We recruited 44 young (age = 10.5 ± 1.8 years old; peak height velocity, PHV = 12.2 ± 0.6 years old) female rhythmic gymnasts and randomly allocated them into a control group (CG) and an experimental group (EG). Pre and post-intervention, the explosive strength of both groups was assessed using countermovement jump (CMJ) and single-leg CMJ (SLCMJ) tests, conducted using a force platform, and expert RG judges evaluated their performance of RG-specific jumps. Before the post-test, the EG (n = 23) completed an 8 week functional CPT program based on RG technical requirements. Meanwhile, the participants in the CG (n = 21) received their regular training sessions. Linear mixed model analyses were applied to evaluate the effects of an intra-subject factor (TIME: pre-post) and an inter-subject factor (GROUP: control-experimental) on each dependent variable. When no significant interaction effect was found, Cohen's d effect size was calculated. Results: After 8 weeks, the EG obtained significantly better results in all variables measured by the CMJ and SLCMJ (p < 0.01) tests. The judges' scores indicated greater improvements in the EG after the CPT program in the stag and the split leap. Conclusions: An integrated functional CPT program improved explosive strength in a group of young rhythmic gymnasts and had a large impact on aspects of RG-specific performance. Coaches should consider using this CPT to improve RG performance.


Assuntos
Desempenho Atlético , Exercício Pliométrico , Criança , Feminino , Humanos , Atletas , Força Muscular , Exercício Pliométrico/métodos
2.
Int J Mol Sci ; 23(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35163825

RESUMO

Enlarged, hypertrophic adipocytes are less responsive to insulin and are a hallmark feature of obesity, contributing to many of the negative metabolic consequences of excess adipose tissue. Although the mechanisms remain unclear, the adipocyte size appears to be inversely correlated with insulin sensitivity and glucose tolerance, wherein smaller adipocytes are insulin-sensitive and larger adipocytes develop insulin resistance and exhibit an impaired glucose uptake. Thus, pharmacological strategies aimed at regulating adipocyte hypertrophy (increase in adipocyte size) in favor of promoting hyperplasia (increase in adipocyte number) have the potential to improve adipocyte insulin sensitivity and provide therapeutic benefits in the context of metabolic disorders. As white adipose tissue can metabolize large amounts of glucose to lactate, using transcriptomics and in vitro characterization we explore the functional consequences of inhibiting monocarboxylate transporter 1 (MCT1) activity in fully differentiated adipocytes. Our studies show that the pharmacological inhibition of MCT1, a key regulator of the cellular metabolism and proliferation, promotes the re-entry of mature adipocytes into the cell cycle. Furthermore, we demonstrate that inhibitor-treated adipocytes exhibit an enhanced insulin-stimulated glucose uptake as compared with untreated adipocytes, and that this outcome is dependent on the cyclin-dependent kinase 1 (CDK1) activity. In summary, we identify a mechanism though which MCT1 inhibition improves the insulin sensitivity of mature adipocytes by inducing cell cycle re-entry. These results provide the foundation for future studies investigating the role MCT1 plays in adipocyte hyperplasia, and its therapeutic potential as a drug target for obesity and metabolic disease.


Assuntos
Adipócitos/citologia , Resistência à Insulina , Transportadores de Ácidos Monocarboxílicos/metabolismo , Pirimidinonas/farmacologia , Simportadores/metabolismo , Tiofenos/farmacologia , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Proteína Quinase CDC2/metabolismo , Ciclo Celular , Proliferação de Células , Regulação para Baixo , Glucose/metabolismo , Camundongos , Modelos Biológicos
3.
Mol Cancer Ther ; 19(8): 1623-1635, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32430484

RESUMO

Although gemcitabine is the cornerstone of care for pancreatic ductal adenocarcinoma (PDA), patients lack durable responses and relapse is inevitable. While the underlying mechanisms leading to gemcitabine resistance are likely to be multifactorial, there is a strong association between activating gemcitabine metabolism pathways and clinical outcome. This study evaluated casein kinase 1 delta (CK1δ) as a potential therapeutic target for PDA and bladder cancer, in which CK1δ is frequently overexpressed. We assessed the antitumor effects of genetically silencing or pharmacologically inhibiting CK1δ using our in-house CK1δ small-molecule inhibitor SR-3029, either alone or in combination with gemcitabine, on the proliferation and survival of pancreatic and bladder cancer cell lines and orthotopic mouse models. Genetic studies confirmed that silencing CK1δ or treatment with SR-3029 induced a significant upregulation of deoxycytidine kinase (dCK), a rate-limiting enzyme in gemcitabine metabolite activation. The combination of SR-3029 with gemcitabine induced synergistic antiproliferative activity and enhanced apoptosis in both pancreatic and bladder cancer cells. Furthermore, in an orthotopic pancreatic tumor model, we observed improved efficacy with combination treatment concomitant with increased dCK expression. This study demonstrates that CK1δ plays a role in gemcitabine metabolism, and that the combination of CK1δ inhibition with gemcitabine holds promise as a future therapeutic option for metastatic PDA as well as other cancers with upregulated CK1δ expression.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Caseína Quinase Idelta/antagonistas & inibidores , Desoxicitidina Quinase/metabolismo , Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Animais , Antimetabólitos Antineoplásicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Desoxicitidina/farmacologia , Desoxicitidina Quinase/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/patologia , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/enzimologia , Neoplasias da Bexiga Urinária/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina , Neoplasias Pancreáticas
4.
Cell Death Differ ; 27(4): 1200-1213, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31506606

RESUMO

Cellular DNA is constantly under threat from internal and external insults, consequently multiple pathways have evolved to maintain chromosomal fidelity. Our previous studies revealed that chronic stress, mediated by continuous stimulation of the ß2-adrenergic-ßarrestin-1 signaling axis suppresses activity of the tumor suppressor p53 and impairs genomic integrity. In this pathway, ßarrestin-1 (ßarr1) acts as a molecular scaffold to promote the binding and degradation of p53 by the E3-ubiquitin ligase, MDM2. We sought to determine whether ßarr1 plays additional roles in the repair of DNA damage. Here we demonstrate that in mice ßarr1 interacts with p53-binding protein 1 (53BP1) with major consequences for the repair of DNA double-strand breaks. 53BP1 is a principle component of the DNA damage response, and when recruited to the site of double-strand breaks in DNA, 53BP1 plays an important role coordinating repair of these toxic lesions. Here, we report that ßarr1 directs 53BP1 degradation by acting as a scaffold for the E3-ubiquitin ligase Rad18. Consequently, knockdown of ßarr1 stabilizes 53BP1 augmenting the number of 53BP1 DNA damage repair foci following exposure to ionizing radiation. Accordingly, ßarr1 loss leads to a marked increase in irradiation resistance both in cells and in vivo. Thus, ßarr1 is an important regulator of double strand break repair, and disruption of the ßarr1/53BP1 interaction offers an attractive strategy to protect cells against high levels of exposure to ionizing radiation.


Assuntos
Reparo do DNA , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , beta-Arrestina 1/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Dano ao DNA , Reparo do DNA/efeitos da radiação , Proteínas de Ligação a DNA/metabolismo , Células HEK293 , Humanos , Intestinos/patologia , Camundongos Endogâmicos C57BL , Ligação Proteica/efeitos da radiação , Processamento de Proteína Pós-Traducional/efeitos da radiação , Tolerância a Radiação/efeitos da radiação , Radiação Ionizante
5.
J Orthop ; 16(6): 590-595, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31686760

RESUMO

HYPOTHESIS: To determine the effect of receiving the visual feedback of the sphygmomanometer on lumbopelvic motor control (LPMC) tests in professional swimmers. METHOD: 31 professional swimmers to participate in the study. The outcome was maximum absolute mmHg variation in the pressure biofeedback unit's manometer with and without visual feedback on four LPMC tests. RESULTS: Test scores were significantly affected by visual feedback F = 10.07, p = 0.002, η2 p = 0.117 and the type of test F = 32.53, p < 0.001, η2 p = 0.300. CONCLUSION: Visual feedback has a positive effect on the Active Straight Leg Raise Test (ASLR), the Knee Lift Abdominal Test (KLAT) scores completed by professional swimmers.

6.
Assay Drug Dev Technol ; 17(6): 275-284, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31532712

RESUMO

Solute carrier proteins (SLCs) are a superfamily of transmembrane transporters that control essential physiological functions such as nutrient uptake, ion transport, and cellular waste elimination. Although many SLCs are associated with various disease states and are considered "druggable," they remain underexplored as a drug target class. One subfamily of SLCs that has gained attention for its therapeutic potential is the monocarboxylate solute transporter family. The monocarboxylate transporter protein 1 (MCT1) is a passive transporter of lactate and has gained significant attention for its role(s) in cancer progression; moreover, upregulation of MCT1 connotes poor patient outcome and survival. Consequently, small molecule inhibitors of MCT1 activity are being pursued as anticancer therapies. However, typical for members of this SLC subfamily, there is a paucity of potent and selective modulators of MCT1. This is in part due to methods used for their identification, typically relying on the use of radiolabeled substrate tracing. In addition to the safety concerns associated with radioactivity, this methodology is also expensive and time consuming. In this study, we describe the use of an MCT1 cytotoxic substrate as a tool to enable the development of a nonradioactive cell-based homogeneous assay that facilitates industry-scale high-throughput screening (HTS) of large compound libraries to identify novel MCT1 inhibitors to interrogate the therapeutic potential of MCT1. Our assay is robust, reproducible, HTS amenable, and establishes a conceptually novel way to identify chemical probes to investigate the therapeutic potential of SLC proteins.


Assuntos
Ensaios de Triagem em Larga Escala , Transportadores de Ácidos Monocarboxílicos/antagonistas & inibidores , Pirimidinonas/farmacologia , Piruvatos/farmacologia , Simportadores/antagonistas & inibidores , Tiofenos/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células HEK293 , Humanos , Camundongos , Estrutura Molecular , Transportadores de Ácidos Monocarboxílicos/metabolismo , Simportadores/metabolismo
7.
Assay Drug Dev Technol ; 16(5): 278-288, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30019946

RESUMO

GPR119 drug discovery efforts in the pharmaceutical industry for the treatment of type 2 diabetes mellitus (T2DM) and obesity, were initiated based on its restricted distribution in pancreas and GI tract, and its possible role in glucose homeostasis. While a number of lead series have emerged, the pharmacological endpoints they provide have not been clear. In particular, many lead series have demonstrated loss of efficacy and significant toxic side effects. Thus, we sought to identify novel, potent, positive modulators of GPR119. In this study, we have successfully developed and optimized a high-throughput screening strategy to identify GPR119 modulators using a live cell assay format that utilizes a cyclic nucleotide-gated channel as a biosensor for cAMP production. Our high-throughput screening (HTS) approach is unique to that of previous HTS approaches targeting this receptor, as changes in cAMP were measured both in the presence and absence of an EC10 of the endogenous ligand, oleoylethanolamide, enabling detection of both agonists and potential allosteric modulators in a single assay. From these efforts, we have identified positive modulators of GPR119 with similar as well as unique scaffolds compared to existing compounds and similar as well as unique signaling properties. Our compounds will not only serve as novel molecular probes to better understand GPR119 pleiotropic signaling and the underlying physiological consequences of receptor activation, but are also well-suited for translation as potential therapeutic agents.


Assuntos
Endocanabinoides/farmacologia , Hipoglicemiantes/farmacologia , Ácidos Oleicos/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Células Cultivadas , Endocanabinoides/química , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Hipoglicemiantes/química , Estrutura Molecular , Ácidos Oleicos/química , Receptores Acoplados a Proteínas G/metabolismo
8.
Nat Commun ; 6: 8918, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26621478

RESUMO

Glucagon-like peptide-1 (GLP-1) receptor (GLP-1R) agonists have emerged as treatment options for type 2 diabetes mellitus (T2DM). GLP-1R signals through G-protein-dependent, and G-protein-independent pathways by engaging the scaffold protein ß-arrestin; preferential signalling of ligands through one or the other of these branches is known as 'ligand bias'. Here we report the discovery of the potent and selective GLP-1R G-protein-biased agonist, P5. We identified P5 in a high-throughput autocrine-based screening of large combinatorial peptide libraries, and show that P5 promotes G-protein signalling comparable to GLP-1 and Exendin-4, but exhibited a significantly reduced ß-arrestin response. Preclinical studies using different mouse models of T2DM demonstrate that P5 is a weak insulin secretagogue. Nevertheless, chronic treatment of diabetic mice with P5 increased adipogenesis, reduced adipose tissue inflammation as well as hepatic steatosis and was more effective at correcting hyperglycaemia and lowering haemoglobin A1c levels than Exendin-4, suggesting that GLP-1R G-protein-biased agonists may provide a novel therapeutic approach to T2DM.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/antagonistas & inibidores , Hipoglicemiantes/administração & dosagem , Peptídeos/administração & dosagem , Adipogenia/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Avaliação Pré-Clínica de Medicamentos , Receptor do Peptídeo Semelhante ao Glucagon 1/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Humanos , Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
9.
Bioorg Med Chem Lett ; 24(16): 3974-8, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24997685

RESUMO

Neurotensin (NT) is an endogenous tridecapeptide found in the central nervous system (CNS) and in peripheral tissues. Neurotensin exerts a wide range of physiological effects and it has been found to play a critical role in a number of human diseases, such as schizophrenia, Parkinson's disease and drug addiction. The discovery of small-molecule non-peptide neurotensin receptor (NTSR) modulators would represent an important breakthrough as such compounds could be used as pharmacological tools, to further decipher the cellular functions of neurotensin, and potentially as therapeutic agents to treat human disease. Herein, we report the identification of non-peptide low-micromolar neurotensin receptor 1 (NTSR1) full agonists, discovered through structural optimization of the known NTSR1 partial agonist 1. In vitro cellular screenings, based on an intracellular Ca(2+) mobilization assay, revealed our best hit molecule 8 (SR-12062) to have an EC50 of 2 µM at NTSR1 with full agonist behaviour (Emax=100%), showing a higher efficacy and ∼90-fold potency improvement compared to parent compound 1 (EC50=178 µM; Emax=17%).


Assuntos
Descoberta de Drogas , Indóis/farmacologia , Receptores de Neurotensina/agonistas , Relação Dose-Resposta a Droga , Humanos , Indóis/síntese química , Indóis/química , Estrutura Molecular , Relação Estrutura-Atividade
10.
J Biomed Inform ; 45(5): 879-84, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22554700

RESUMO

Corpora with specific entities and relationships annotated are essential to train and evaluate text-mining systems that are developed to extract specific structured information from a large corpus. In this paper we describe an approach where a named-entity recognition system produces a first annotation and annotators revise this annotation using a web-based interface. The agreement figures achieved show that the inter-annotator agreement is much better than the agreement with the system provided annotations. The corpus has been annotated for drugs, disorders, genes and their inter-relationships. For each of the drug-disorder, drug-target, and target-disorder relations three experts have annotated a set of 100 abstracts. These annotated relationships will be used to train and evaluate text-mining software to capture these relationships in texts.


Assuntos
Mineração de Dados/métodos , Bases de Dados Factuais , Informática Médica/métodos , Documentação , Tratamento Farmacológico/classificação , Humanos , Internet , Preparações Farmacêuticas/classificação , Interface Usuário-Computador
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