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1.
Curr Med Res Opin ; 38(6): 875-880, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35593160

RESUMO

Recent increases in the practice of parallel publication, during which a peer-reviewed manuscript is published concurrently with the first dissemination of the same key data at a medical congress as a late-breaking abstract, have highlighted substantial value for this method of publication. Parallel publication can increase access to new clinical information for healthcare providers and patients, as well as promote engagement and reach of the publication and presentation. As the practice becomes more common, there is a need for strategies to address the multiple challenges involved in the development process, such as shortened timelines, journal and congress policies, and stakeholder alignment. We surveyed journals, congresses, and publication professionals on the challenges of parallel publication and recommendations for success. Recommendations from journal editors and congress officials included the importance of adhering to timelines and early communication. Insights from a community of publication professionals showed that timelines and the author review process were among the key challenges of parallel publication development and stressed the importance of clear roles and expectations for authors. To provide real-world insights, we present 3 case studies of successful parallel publication development, highlighting the crucial role of journal selection, planning around data availability, and adapting to unpredictable circumstances. The recommendations described here may provide publication professionals with strategies to successfully plan, execute, and carry out parallel publication.


Assuntos
Comunicação , Editoração , Humanos
2.
Assay Drug Dev Technol ; 9(4): 373-81, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21294696

RESUMO

Mitochondrial dysfunction is increasingly associated with disease states. These organelles, responsible for adenosine triphosphate production, have been targeted for improved function in such diseases as Parkinson's, Alzheimer's, type 2 diabetes, and sarcopenia. In addition, the importance of determining if a clinical drug candidate adversely effects mitochondria function, which could lead to overt toxicity, has been recognized. Hence, assays that measure mitochondria activity have become essential in early stage drug development. Limitations of current assays that measure mitochondria membrane potential have prohibited the high-throughput performance necessary to screen current chemical space. Here, we describe a homogeneous assay to measure mitochondria membrane potential that can utilize either adherent or suspension cell types. The assay has been miniaturized to 1,536-well plate format, and was used to perform a fully automated robotic high-throughput screen of a small molecule chemical library.


Assuntos
Bioensaio/métodos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Animais , Células CHO , Carbonil Cianeto m-Clorofenil Hidrazona/metabolismo , Corantes/metabolismo , Cricetinae , Avaliação Pré-Clínica de Medicamentos/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/metabolismo , Ensaios de Triagem em Larga Escala , Humanos , Células Jurkat , Medições Luminescentes , Miniaturização , Mitocôndrias/metabolismo , Ionóforos de Próton/metabolismo , Rodaminas/metabolismo , Fatores de Tempo
3.
J Biol Chem ; 286(7): 5215-21, 2011 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-21118811

RESUMO

Apolipoprotein (apo) E4 is the major genetic risk factor for late-onset Alzheimer disease (AD). ApoE4 assumes a pathological conformation through an intramolecular interaction mediated by Arg-61 in the amino-terminal domain and Glu-255 in the carboxyl-terminal domain, referred to as apoE4 domain interaction. Because AD is associated with mitochondrial dysfunction, we examined the effect of apoE4 domain interaction on mitochondrial respiratory function. Steady-state amounts of mitochondrial respiratory complexes were examined in neurons cultured from brain cortices of neuron-specific enolase promoter-driven apoE3 (NSE-apoE3) or apoE4 (NSE-apoE4) transgenic mice. All subunits of mitochondrial respiratory complexes assessed were significantly lower in NSE-apoE4 neurons compared with NSE-apoE3 neurons. However, no significant differences in levels of mitochondrial complexes were detected between astrocytes expressing different apoE isoforms driven by the glial fibrillary acidic protein promoter, leading to our conclusion that the effect of apoE4 is neuron specific. In neuroblastoma Neuro-2A (N2A) cells, apoE4 expression reduced the levels of mitochondrial respiratory complexes I, IV, and V. Complex IV enzymatic activity was also decreased, lowering mitochondrial respiratory capacity. Mutant apoE4 (apoE4-Thr-61) lacking domain interaction did not induce mitochondrial dysfunction in N2A cells, indicating that the effect is specific to apoE4-expressing cells and dependent on domain interaction. Consistent with this finding, treatment of apoE4-expressing N2A cells with a small molecule that disrupts apoE4 domain interaction restored mitochondrial respiratory complex IV levels. These results suggest that pharmacological intervention with small molecules that disrupt apoE4 domain interaction is a potential therapeutic approach for apoE4-carrying AD subjects.


Assuntos
Doença de Alzheimer/metabolismo , Apolipoproteína E4/metabolismo , Mitocôndrias/metabolismo , Neurônios/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Animais , Apolipoproteína E4/genética , Linhagem Celular Tumoral , Transporte de Elétrons/genética , Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Humanos , Camundongos , Camundongos Knockout , Mitocôndrias/genética , Mitocôndrias/patologia , Neurônios/patologia , Estrutura Terciária de Proteína , Fatores de Risco
4.
J Endocrinol ; 207(1): 113-22, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20675300

RESUMO

Unsuccessful attempts to identify the leptin gene in birds are well documented, despite the characterization of its receptor (LEPR). Since leptin and LEPR have poor sequence conservation among vertebrates, we speculated that a functional assay should represent the best way to detect leptin in birds. Using a leptin bioassay that is based on activation of the chicken LEPR in cultured cells, blood samples from wild birds with extreme seasonal variation in voluntary food intake and fat deposition (Adélie penguins and bar-tailed godwits) were tested for leptin activity. In these experiments, blood samples collected during the pre-incubation and the chick-rearing periods of Adélie penguins, and during the migratory flight and refueling stages of bar-tailed godwits, were found to contain no detectable leptin activity, while the sensitivity of the assay to activation by human blood samples from donor subjects representing a variety of body mass indices and fat contents was clearly demonstrated. These results suggest that in birds, an alternative control mechanism to that of mammals operates in the communication between the body fat tissues and the central control on energy homeostasis.


Assuntos
Charadriiformes/sangue , Spheniscidae/sangue , Tecido Adiposo/anatomia & histologia , Migração Animal/fisiologia , Animais , Charadriiformes/anatomia & histologia , Charadriiformes/fisiologia , Ingestão de Alimentos/fisiologia , Feminino , Humanos , Masculino , Reprodução/fisiologia , Estações do Ano , Especificidade da Espécie , Spheniscidae/anatomia & histologia , Spheniscidae/fisiologia
6.
J Neurochem ; 110(1): 390-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19457101

RESUMO

The co-existence of receptors for leptin and melanocortin in cerebral microvessels suggests possible interactions between leptin and alpha-melanocyte stimulating hormone (MSH) signaling. In this study, we showed that ObRb and melanocortin receptor MC3R and MC4R were present in enriched cerebral microvessels. To test the interactions between ObRb and MC3R or MC4R-mediated cellular signaling, we over-expressed these plasmids in RBE4 cerebral microvascular endothelial cells and HEK293 cells in culture. Activation of signal transducers and activators of transcription-3 (STAT3) in response to leptin was determined by western blotting and luciferase reporter assays. Production of cAMP downstream to melanocortin receptors was determined with a chemiluminescent ELISA kit. alphaMSH, which increased intracellular cAMP, also potentiated leptin-induced STAT3 activation. This potentiation was abolished by a specific MEK inhibitor, indicating the involvement of the mitogen-activated kinase pathway. Reversely, the effect of leptin on alphaMSH-induced cAMP production was minimal. Thus, melanocortin specifically potentiated STAT3 signaling downstream to ObRb by cross-talk with mitogen-activated kinase. The cooperation of ObRb and G protein-coupled receptors in cellular signaling may have considerable biological implications not restricted to feeding and obesity.


Assuntos
Artérias Cerebrais/metabolismo , Leptina/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Melanocortinas/metabolismo , Receptores para Leptina/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Linhagem Celular , Artérias Cerebrais/efeitos dos fármacos , AMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Comportamento Alimentar/efeitos dos fármacos , Comportamento Alimentar/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Humanos , Leptina/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melanocortinas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Microcirculação/efeitos dos fármacos , Microcirculação/fisiologia , Receptor Cross-Talk/efeitos dos fármacos , Receptor Cross-Talk/fisiologia , Receptor Tipo 3 de Melanocortina/agonistas , Receptor Tipo 3 de Melanocortina/genética , Receptor Tipo 3 de Melanocortina/metabolismo , Receptor Tipo 4 de Melanocortina/agonistas , Receptor Tipo 4 de Melanocortina/genética , Receptor Tipo 4 de Melanocortina/metabolismo , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismo , Receptores para Leptina/efeitos dos fármacos , Receptores para Leptina/genética , Fator de Transcrição STAT3/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , alfa-MSH/metabolismo , alfa-MSH/farmacologia
7.
J Endocrinol ; 197(2): 325-33, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18434362

RESUMO

We report on the construction of a leptin bioassay based on the activation of chicken leptin receptor in cultured cells. A human embryonic kidney (HEK)-293 cell line, stably transfected with the full-length cDNA of chicken leptin receptor together with a STAT3-responsive reporter gene specifically responded to recombinant human and Xenopus leptins. The observed higher sensitivity of chicken leptin receptor to the former is in agreement with the degree of sequence similarity among these species (about 60 and 38% identical amino acids between humans and chickens, and between humans and Xenopus respectively). The specific activation of signal transduction through the chicken leptin receptor, shown here for the first time, suggests that the transition of Gln269 (implicated in the Gln-to-Pro Zucker fatty mutation in rats) to Glu in chickens does not impair its activity. Analysis of leptin-like activity in human serum samples of obese and lean subjects coincided well with leptin levels determined by RIA. Serum samples of pre- and post partum cows showed a tight correlation with the degree of adiposity. However, specific activation of the chicken leptin receptor in this assay was not observed with serum samples from broiler or layer chickens (representing fat and lean phenotypes respectively) or with those from turkey. Similar leptin receptor activation profiles were observed with cells transfected with human leptin receptor. Further work is needed to determine whether the lack of leptin-like activity in the chicken serum samples is due to a lack of leptin in this species or simply to a serum level of leptin that is below the detection threshold.


Assuntos
Leptina/sangue , Receptores para Leptina/genética , Sequência de Aminoácidos , Animais , Bioensaio , Bovinos , Linhagem Celular , Galinhas , Humanos , Dados de Sequência Molecular , Receptores para Leptina/química , Xenopus
8.
Bioorg Med Chem Lett ; 15(15): 3501-5, 2005 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15982875

RESUMO

A novel isoquinuclidine containing selective melanocortin subtype-4 receptor small molecule agonist, 3 (RY764), is reported. Its in vivo characterization revealed mechanism-based food intake reduction and erectile activity augmentation in rodents.


Assuntos
Compostos Aza/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Ereção Peniana/efeitos dos fármacos , Piperazinas/farmacologia , Piperidinas/farmacologia , Receptor Tipo 4 de Melanocortina/agonistas , Animais , Compostos Aza/síntese química , Humanos , Masculino , Microssomos Hepáticos/metabolismo , Piperazinas/química , Piperidinas/síntese química , Ligação Proteica , Quinuclidinas/química , Ratos , Ratos Sprague-Dawley , Roedores , Relação Estrutura-Atividade , Fatores de Tempo
9.
Bioorg Med Chem Lett ; 15(8): 1993-6, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15808454

RESUMO

We report the discovery and optimization of substituted 2-piperazinecarboxamides as potent and selective agonists of the melanocortin subtype-4 receptor. The 5- and 6-alkylated piperazine compounds exhibit low bioactivation potential as measured by covalent binding in microsome preparations.


Assuntos
Piperazinas/química , Piperazinas/farmacologia , Receptor Tipo 4 de Melanocortina/agonistas , Humanos , Piperazinas/metabolismo , Receptor Tipo 4 de Melanocortina/metabolismo , Relação Estrutura-Atividade
11.
Regul Pept ; 120(1-3): 113-8, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15177928

RESUMO

The melanocortin 4 receptor (MC4-R) is a Galpha s-coupled receptor known to increase cAMP production following agonist stimulation. We demonstrate that the mitogen-activated protein kinases p42 (ERK2) and p44 (ERK1) are also activated by MC4-R following treatment with the MC4-R agonist NDP-alpha-MSH in stably transfected CHO-K1 cells. This time- and dose-dependent response is abolished by the MC4-R antagonist SHU-9119. p42/p44 MAPK activation is blocked by the phosphatidylinositol 3-kinase (PI3K) inhibitors wortmannin and LY294002 but not by the protein kinase A (PKA) inhibitor Rp-cAMPS, indicating that that signal activating the p42/p44 MAPK pathway is conveyed through inositol triphosphate.


Assuntos
Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Receptor Tipo 4 de Melanocortina/antagonistas & inibidores , Androstadienos/farmacologia , Animais , Células CHO , Células Cultivadas , Cromonas/farmacologia , Cricetinae , AMP Cíclico/análogos & derivados , AMP Cíclico/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/farmacologia , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Hormônios Estimuladores de Melanócitos/farmacologia , Morfolinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Receptor Tipo 4 de Melanocortina/metabolismo , Transdução de Sinais , Wortmanina
13.
Wound Repair Regen ; 10(5): 302-7, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12406166

RESUMO

The adiposity hormone leptin regulates food intake, body weight, reproduction and other metabolic and endocrine functions mainly through signaling to the hypothalamus. Leptin signaling to peripheral tissues other than the hypothalamus has been suggested for a number of processes such as immunity, bone metabolism, hematopoiesis, angiogenesis, and wound healing. It was previously shown that exogenously applied leptin accelerated wound healing and that leptin mRNA is expressed at the wound site, but there is no published evidence showing that it is translated into leptin protein that is available at the site of repair. To address this question we analyzed pig wound fluids collected from partial-thickness excisional wounds during the first 9 days after injury. Leptin was measured using a modified culture of HEK-293 cells, expressing both the human leptin receptor gene and the firefly luciferase gene driven by a STAT-inducible promoter. Relatively high levels of leptin activity (50-250 ng/ml) were detected in wound fluids using the leptin receptor expressing HEK-293 cells. Our results suggest that leptin is normally induced (4.8- to 10.2-fold) in wound tissue during the first few days following injury and may operate in a paracrine or autocrine circuit during the wound repair process.


Assuntos
Líquidos Corporais/metabolismo , Leptina/metabolismo , Pele/metabolismo , Cicatrização , Animais , Células Cultivadas , Humanos , Rim/citologia , Luciferases/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores para Leptina , Pele/lesões , Suínos
14.
Eur J Pharmacol ; 450(1): 93-109, 2002 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-12176114

RESUMO

Five G-protein-coupled melanocortin receptors (MC(1)-MC(5)) are expressed in mammalian tissues. The melanocortin receptors support diverse physiological functions, including the regulation of hair color, adrenal function, energy homeostasis, feed efficiency, sebaceous gland lipid production and immune and sexual function. The melanocortins (adrenocorticotropic hormone (ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), beta-MSH and gamma-MSH) are agonist peptide ligands for the melanocortin receptors and these peptides are processed from the pre-prohormone proopiomelanocortin (POMC). Peptide antagonists for the melanocortin MC(1), MC(3) and MC(4) receptors include agouti-related protein (AgRP) and agouti. Diverse lines of evidence, including genetic and pharmacological data obtained in rodents and humans, support a role for the melanocortin MC(3) and MC(4) receptors in the regulation of energy homeostasis. Recent advances in the development of potent and selective peptide and non-peptide melanocortin receptor ligands are anticipated to help unravel the roles for the melanocortin receptors in humans and to accelerate the clinical use of small molecule melanocortin mimetics.


Assuntos
Peso Corporal/fisiologia , Hormônios Estimuladores de Melanócitos/fisiologia , Obesidade/fisiopatologia , Animais , Fármacos Antiobesidade/química , Fármacos Antiobesidade/uso terapêutico , Peso Corporal/efeitos dos fármacos , Expressão Gênica , Humanos , Hormônios Estimuladores de Melanócitos/genética , Obesidade/tratamento farmacológico , Receptores da Corticotropina/efeitos dos fármacos , Receptores da Corticotropina/genética , Receptores da Corticotropina/fisiologia , Receptores de Melanocortina
15.
Eur J Pharmacol ; 440(2-3): 141-57, 2002 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-12007532

RESUMO

Five G-protein-coupled melanocortin receptors (MC(1)-MC(5)) are expressed in mammalian tissues. The melanocortin receptors support diverse physiological functions, including the regulation of hair color, adrenal function, energy homeostasis, feed efficiency, sebaceous gland lipid production and immune and sexual function. The melanocortins (adrenocorticotropic hormone (ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), beta-MSH and gamma-MSH) are agonist peptide ligands for the melanocortin receptors and these peptides are processed from the pre-prohormone proopiomelanocortin (POMC). Peptide antagonists for the melanocortin MC(1), MC(3) and MC(4) receptors include agouti-related protein (AgRP) and agouti. Diverse lines of evidence, including genetic and pharmacological data obtained in rodents and humans, support a role for the melanocortin MC(3) and MC(4) receptors in the regulation of energy homeostasis. Recent advances in the development of potent and selective peptide and non-peptide melanocortin receptor ligands are anticipated to help unravel the roles for the melanocortin receptors in humans and to accelerate the clinical use of small molecule melanocortin mimetics.


Assuntos
Peso Corporal/fisiologia , Hormônios Estimuladores de Melanócitos/fisiologia , Obesidade/fisiopatologia , Animais , Fármacos Antiobesidade/química , Fármacos Antiobesidade/uso terapêutico , Peso Corporal/efeitos dos fármacos , Expressão Gênica , Humanos , Hormônios Estimuladores de Melanócitos/genética , Obesidade/tratamento farmacológico , Receptores da Corticotropina/efeitos dos fármacos , Receptores da Corticotropina/genética , Receptores da Corticotropina/fisiologia , Receptores de Melanocortina
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