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1.
Aging (Albany NY) ; 16(13): 10694-10723, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38976646

RESUMO

Idiopathic pulmonary fibrosis (IPF) is an age-related disease with poor prognosis and limited therapeutic options. Activation of lung fibroblasts and differentiation to myofibroblasts are the principal effectors of disease pathology, but damage and senescence of alveolar epithelial cells, specifically type II (ATII) cells, has recently been identified as a potential trigger event for the progressive disease cycle. Targeting ATII senescence and the senescence-associated secretory phenotype (SASP) is an attractive therapeutic strategy; however, translatable primary human cell models that enable mechanistic studies and drug development are lacking. Here, we describe a novel system of conditioned medium (CM) transfer from bleomycin-induced senescent primary alveolar epithelial cells (AEC) onto normal human lung fibroblasts (NHLF) that demonstrates an enhanced fibrotic transcriptional and secretory phenotype compared to non-senescent AEC CM treatment or direct bleomycin damage of the NHLFs. In this system, the bleomycin-treated AECs exhibit classical hallmarks of cellular senescence, including SASP and a gene expression profile that resembles aberrant epithelial cells of the IPF lung. Fibroblast activation by CM transfer is attenuated by pre-treatment of senescent AECs with the senolytic Navitoclax and AD80, but not with the standard of care agent Nintedanib or senomorphic JAK-targeting drugs (e.g., ABT-317, ruxolitinib). This model provides a relevant human system for profiling novel senescence-targeting therapeutics for IPF drug development.


Assuntos
Células Epiteliais Alveolares , Bleomicina , Senescência Celular , Fibroblastos , Fibrose Pulmonar Idiopática , Humanos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Bleomicina/toxicidade , Bleomicina/farmacologia , Senescência Celular/efeitos dos fármacos , Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/metabolismo , Meios de Cultivo Condicionados/farmacologia , Indóis/farmacologia , Fenótipo Secretor Associado à Senescência/efeitos dos fármacos , Pulmão/patologia , Pulmão/citologia , Pulmão/efeitos dos fármacos , Sulfonamidas/farmacologia , Senoterapia/farmacologia , Células Cultivadas , Pirimidinas/farmacologia , Pirazóis/farmacologia , Nitrilas/farmacologia , Compostos de Anilina
2.
Front Immunol ; 15: 1293883, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38455057

RESUMO

Fibrotic diseases, such as idiopathic pulmonary fibrosis (IPF) and systemic scleroderma (SSc), are commonly associated with high morbidity and mortality, thereby representing a significant unmet medical need. Interleukin 11 (IL11)-mediated cell activation has been identified as a central mechanism for promoting fibrosis downstream of TGFß. IL11 signaling has recently been reported to promote fibroblast-to-myofibroblast transition, thus leading to various pro-fibrotic phenotypic changes. We confirmed increased mRNA expression of IL11 and IL11Rα in fibrotic diseases by OMICs approaches and in situ hybridization. However, the vital role of IL11 as a driver for fibrosis was not recapitulated. While induction of IL11 secretion was observed downstream of TGFß signaling in human lung fibroblasts and epithelial cells, the cellular responses induced by IL11 was quantitatively and qualitatively inferior to that of TGFß at the transcriptional and translational levels. IL11 blocking antibodies inhibited IL11Rα-proximal STAT3 activation but failed to block TGFß-induced profibrotic signals. In summary, our results challenge the concept of IL11 blockade as a strategy for providing transformative treatment for fibrosis.


Assuntos
Interleucina-11 , Fator de Crescimento Transformador beta , Humanos , Fator de Crescimento Transformador beta/metabolismo , Transdução de Sinais , Fibrose , Miofibroblastos/metabolismo
3.
Toxicol Sci ; 191(2): 400-413, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36515490

RESUMO

Administration of a novel and selective small molecule integrin αvß6 inhibitor, MORF-627, to young cynomolgus monkeys for 28 days resulted in the rapid induction of epithelial proliferative changes in the urinary bladder of 2 animals, in the absence of test agent genotoxicity. Microscopic findings included suburothelial infiltration by irregular nests and/or trabeculae of epithelial cells, variable cytologic atypia, and high mitotic rate, without invasion into the tunica muscularis. Morphologic features and patterns of tumor growth were consistent with a diagnosis of early-stage invasive urothelial carcinoma. Ki67 immunohistochemistry demonstrated diffusely increased epithelial proliferation in the urinary bladder of several monkeys, including those with tumors, and αvß6 was expressed in some epithelial tissues, including urinary bladder, in monkeys and humans. Spontaneous urothelial carcinomas are extremely unusual in young healthy monkeys, suggesting a direct link of the finding to the test agent. Inhibition of integrin αvß6 is intended to locally and selectively block transforming growth factor beta (TGF-ß) signaling, which is implicated in epithelial proliferative disorders. Subsequent in vitro studies using a panel of integrin αvß6 inhibitors in human bladder epithelial cells replicated the increased urothelial proliferation observed in monkeys and was reversed through exogenous application of TGF-ß. Moreover, analysis of in vivo models of liver and lung fibrosis revealed evidence of epithelial hyperplasia and cell cycle dysregulation in mice treated with integrin αvß6 or TGF-ß receptor I inhibitors. The cumulative evidence suggests a direct link between integrin αvß6 inhibition and decreased TGF-ß signaling in the local bladder environment, with implications for epithelial proliferation and carcinogenesis.


Assuntos
Carcinoma de Células de Transição , Integrinas , Neoplasias da Bexiga Urinária , Animais , Humanos , Camundongos , Carcinoma de Células de Transição/induzido quimicamente , Integrinas/antagonistas & inibidores , Integrinas/metabolismo , Macaca fascicularis , Fator de Crescimento Transformador beta/metabolismo , Neoplasias da Bexiga Urinária/induzido quimicamente
4.
Sci Immunol ; 7(78): eabq6691, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36490328

RESUMO

Immune cells are fundamental regulators of extracellular matrix (ECM) production by fibroblasts and have important roles in determining extent of fibrosis in response to inflammation. Although much is known about fibroblast signaling in fibrosis, the molecular signals between immune cells and fibroblasts that drive its persistence are poorly understood. We therefore analyzed skin and lung samples of patients with diffuse cutaneous systemic sclerosis, an autoimmune disease that causes debilitating fibrosis of the skin and internal organs. Here, we define a critical role of epiregulin-EGFR signaling between dendritic cells and fibroblasts to maintain elevated ECM production and accumulation in fibrotic tissue. We found that epiregulin expression marks an inducible state of DC3 dendritic cells triggered by type I interferon and that DC3-derived epiregulin activates EGFR on fibroblasts, driving a positive feedback loop through NOTCH signaling. In mouse models of skin and lung fibrosis, epiregulin was essential for persistence of fibrosis in both tissues, which could be abrogated by epiregulin genetic deficiency or a neutralizing antibody. Therapeutic administration of epiregulin antibody reversed fibrosis in patient skin and lung explants, identifying it as a previously unexplored biologic drug target. Our findings reveal epiregulin as a crucial immune signal that maintains skin and lung fibrosis in multiple diseases and represents a promising antifibrotic target.


Assuntos
Fibrose Pulmonar , Camundongos , Animais , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Ligantes , Pele/patologia , Fibrose , Células Dendríticas
5.
Arch Toxicol ; 85(5): 513-23, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21046364

RESUMO

Dibromoacetic acid (DBAA), a by-product formed during disinfection of drinking water, alters spermatogenesis in rats through defective spermiation. The mechanism underlying this toxicity is not fully understood. In this study, gene expression data generated with microarrays from testes were used to generate a mechanistic understanding of DBAA-induced testicular toxicity. Testes were collected from male Sprague-Dawley rats dosed orally for 1 and 4 days with DBAA at 250 mg/kg/day. At both time points, DBAA administration induced delayed spermiation in Stage X tubules and regulated the expression of a small number of genes, including a mild but consistent downregulation of cytochrome P450c17α (CYP17) mRNA, an enzyme expressed by Leydig cells and essential for the production of testicular androgens. Downregulation of CYP17 was confirmed at the protein level and its biological significance was substantiated by demonstrating reduced testicular testosterone levels in DBAA-dosed rats. Furthermore, testosterone production by human chorionic gonadotrophin (hCG)-stimulated rat primary Leydig cells was reduced following treatment with 100 µM DBAA. Collectively, these results indicate that DBAA can directly target rat Leydig cells and downregulate testicular CYP17 expression with a resulting decreased testicular testosterone production. This disruption of testicular steroidogenesis is likely to contribute to the mechanism of failed spermiation observed in rats following exposure to DBAA.


Assuntos
Acetatos/toxicidade , Esteroide 17-alfa-Hidroxilase/metabolismo , Doenças Testiculares/patologia , Testículo/patologia , Animais , Gonadotropina Coriônica/metabolismo , Regulação para Baixo , Perfilação da Expressão Gênica , Humanos , Células Intersticiais do Testículo/metabolismo , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Espermatogênese/efeitos dos fármacos , Esteroide 17-alfa-Hidroxilase/genética , Doenças Testiculares/induzido quimicamente , Testosterona/biossíntese
6.
Bioorg Med Chem Lett ; 20(6): 1900-4, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20171098

RESUMO

Three novel series of histamine H(4) receptor (H(4)R) antagonists containing the 2-aminopyrimidine motif are reported. The best of these compounds display good in vitro potency in both functional and binding assays. In addition, representative compounds are able to completely block itch responses when dosed ip in a mouse model of H(4)-agonist induced scratching, thus demonstrating their activities as H(4)R antagonists.


Assuntos
Aminopiridinas/farmacologia , Antagonistas dos Receptores Histamínicos/farmacologia , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Animais , Humanos , Camundongos , Receptores Histamínicos , Receptores Histamínicos H4
7.
Qual Health Res ; 20(10): 1379-92, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20530402

RESUMO

Although nurses of the past and present recognize the importance of spiritual care to health and healing, in practice and education, spiritual care dwells on the periphery of the profession. The purpose of this study was to gain a better understanding of the reasons behind this contradiction. Using the phenomenological approach, open-ended interviews were conducted with 29 individuals, including oncology nurses, patients and their families, chaplains, and hospital administrators. Their accounts reveal examples of how attitudes, beliefs, and practices of the larger organizational culture can shape the everyday lived experience of bedside nursing. Specifically, these influences tend to create a lived space that is uncaring, and a lived time that is "too tight." Moreover, lived body is experienced as an object for technical intervention, and lived other is experienced from a distance rather than "up close and personal." It was argued that, together, these existential experiences of lived time, space, body, and other create formidable barriers to spiritual nursing care.


Assuntos
Enfermagem Oncológica , Filosofia em Enfermagem , Espiritualidade , Canadá , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Entrevista Psicológica , Masculino , Carga de Trabalho , Local de Trabalho/psicologia
8.
Assay Drug Dev Technol ; 6(3): 339-49, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18593375

RESUMO

Guanosine 5'-O-(3-[(35)S]thio)triphosphate ([(35)S]GTPgammaS) binding assays were established and utilized as a reliable and high-capacity functional assay for determining antagonist and inverse agonist pharmacological parameters of novel histamine H(3) ligands, at the recombinant human H(3) receptor. [(35)S]GTPgammaS binding assays were performed with membranes prepared from human embryonic kidney 293 cells stably expressing the full-length (445 amino acids) human H(3) receptor isoform, at approximately 1 pmol/mg of protein. Utilizing robotic liquid handling, assay filtration, and scintillation counting in a 96-well format, concentration-response curves were determined for up to 40 compounds per assay. The imidazole-containing H(3) receptor antagonist ciproxifan and the non-imidazole antagonist ABT-239 inhibited (R)-alpha-methylhistamine (RAMH)-stimulated [(35)S]GTPgammaS binding in a competitive manner, and negative logarithm of the dissociation equilibrium constant (pK(b)) values determined for nearly 200 structurally diverse H(3) antagonists were very similar to the respective negative logarithm of the equilibrium inhibition constant values from N-alpha-[(3)H]methylhistamine competition binding assays. H(3) antagonists also concentration-dependently decreased basal [(35)S]GTPgammaS binding, thereby displaying inverse agonism at the constitutively active H(3) receptor. At maximally effective concentrations, non-imidazole H(3) antagonists inhibited basal [(35)S]GTPgammaS binding by approximately 20%. For over 100 of these antagonists, negative logarithm of the 50% effective concentration values for inverse agonism were very similar to the respective pK(b) values. Both H(3) receptor agonist-dependent and -independent (constitutive) [(35)S]GTPgammaS binding were sensitive to changes in assay concentrations of sodium, magnesium, and the guanine nucleotide GDP; however, the potency of ABT-239 for inhibition of RAMH-stimulated [(35)S]GTPgammaS binding was not significantly affected. These robust and reliable [(35)S]GTPgammaS binding assays have become one of the important tools in our pharmacological analysis and development of novel histamine H(3) receptor antagonists/inverse agonists.


Assuntos
Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Agonistas dos Receptores Histamínicos/farmacologia , Antagonistas dos Receptores Histamínicos H3/farmacologia , Receptores Histamínicos H3/efeitos dos fármacos , Radioisótopos de Enxofre , Benzofuranos/farmacologia , Linhagem Celular , Agonismo Inverso de Drogas , Humanos , Ligantes , Metilistaminas/farmacologia , Pirrolidinas/farmacologia
9.
Qual Health Res ; 18(5): 686-700, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18227195

RESUMO

Although the importance of spiritual care is widely recognized in nursing theory, recent research suggests that it is rarely attended to in nursing practice. One explanation for this contradiction is the conceptual confusion that exists regarding the meaning of spiritual nursing care. To help unravel this confusion, in-depth open-ended interviews were conducted in an oncology care setting with 29 individuals representing the multiple perspectives of nurses, patients, family, and others. Phenomenological analysis of these interviews reveals that spiritual nursing care involves a complexity of social processes, of which developing caring relationships is core. For these social processes to work and for spiritual nursing care to be realized, the nurse must embody four essential human qualities: receptivity, humanity, competency, and positivity. Participants' descriptions of these processes and qualities not only offer clarity and understanding but also capture the diffuse and amorphous nature of spiritual nursing care.


Assuntos
Enfermagem Oncológica/métodos , Espiritualidade , Competência Clínica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Papel do Profissional de Enfermagem , Relações Enfermeiro-Paciente , Teoria de Enfermagem , Pesquisa Qualitativa
10.
Br J Pharmacol ; 148(5): 657-70, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16715122

RESUMO

1. A-349821 is a selective histamine H3 receptor antagonist/inverse agonist. Herein, binding of the novel non-imidazole H3 receptor radioligand [3H]A-349821 to membranes expressing native or recombinant H3 receptors from rat or human sources was characterized and compared with the binding of the agonist [3H]N--methylhistamine ([3H]NMH). 2. [3H]A-349821 bound with high affinity and specificity to an apparent single class of saturable sites and recognized human H3 receptors with 10-fold higher affinity compared to rat H3 receptors. [3H]A-349821 detected larger populations of receptors compared to [3H]NMH. 3. Displacement of [3H]A-349821 binding by H3 receptor antagonists/inverse agonists was monophasic, suggesting recognition of a single binding site, while that of H3 receptor agonists was biphasic, suggesting recognition of both high- and low-affinity H3 receptor sites. 4. pKi values of high-affinity binding sites for H3 receptor competitors utilizing [3H]A-349821 were highly correlated with pKi values obtained with [3H]NalphaMH, consistent with labelling of H3 receptors by [3H]A-349821. 5. Unlike assays utilizing [3H]NMH, addition of GDP had no effect on saturation parameters measured with [3H]A-349821, while displacement of [3H]A-349821 binding by the H3 receptor agonist histamine was sensitive to GDP. 6. In conclusion, [3H]A-349821 labels interconvertible high- and low-affinity states of the H3 receptor, and displays improved selectivity over imidazole-containing H3 receptor antagonist radioligands. [3H]A-349821 competition studies showed significant differences in the proportions and potencies of high- and low-affinity sites across species, providing new information about the fundamental pharmacological nature of H3 receptors.


Assuntos
Compostos de Bifenilo/farmacocinética , Antagonistas dos Receptores Histamínicos/farmacologia , Ensaio Radioligante/métodos , Receptores Histamínicos H3/química , Receptores Histamínicos H3/metabolismo , Animais , Ligação Competitiva/efeitos dos fármacos , Células Cultivadas , Guanosina Difosfato/farmacologia , Histamina/farmacologia , Agonistas dos Receptores Histamínicos/farmacologia , Humanos , Imidazóis/farmacologia , Metilistaminas/farmacologia , Modelos Biológicos , Ligação Proteica/efeitos dos fármacos , Ratos , Tioureia/análogos & derivados , Tioureia/farmacologia
11.
J Nurses Prof Dev ; 31(1): 28-34, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25608094

RESUMO

To support evidence-based practice changes in long-term care, we used a practice development approach with interactive workshops to engage teams from 10 organizations in participatory change. Data from postworkshop surveys and subsequent semistructured interviews indicated that participants felt empowered to identify a priority challenge and initiate change. Notably, the workshop intervention enhanced collaboration between professional and unregulated staff, fostered the development of shared vision, and provided the impetus to tackle workplace barriers to change.


Assuntos
Assistência de Longa Duração/organização & administração , Inovação Organizacional , Desenvolvimento de Programas , Comportamento Cooperativo , Enfermagem Baseada em Evidências , Humanos , Enfermeiras e Enfermeiros , Ontário , Avaliação de Programas e Projetos de Saúde , Inquéritos e Questionários , Ensino/métodos
12.
J Med Chem ; 47(12): 3220-35, 2004 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-15163201

RESUMO

Structure-activity studies were performed on the alpha(1A)-adrenoceptor (AR) selective agonist N-[5-(1H-imidazol-4-yl)-5,6,7,8-tetrahydro-1-naphthalenyl]methanesulfonamide (4). Compounds were evaluated for binding activity at the alpha(1A), alpha(1b), alpha(1d), alpha(2a), and alpha(2B) subtypes. Functional activity in tissues containing the alpha(1A) (rabbit urethra), alpha(1B) (rat spleen), alpha(1D) (rat aorta), and alpha(2A) (rat prostatic vas deferens) was also evaluated. A dog in vivo model simultaneously measuring intraurethral pressure (IUP) and mean arterial pressure (MAP) was used to assess the uroselectivity of the compounds. Many of the compounds that were highly selective in vitro for the alpha(1A)-AR subtype were also more uroselective in vivo for increasing IUP over MAP than the nonselective alpha(1)-agonists phenylpropanolamine (PPA) (1) and ST-1059 (2, the active metabolite of midodrine), supporting the hypothesis that greater alpha(1A) selectivity would reduce cardiovascular side effects. However, the data also support a prominent role of the alpha(1A)-AR subtype in the control of MAP.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 1 , Imidazóis/síntese química , Naftalenos/síntese química , Sulfonamidas/síntese química , Tetra-Hidronaftalenos/síntese química , Animais , Aorta/efeitos dos fármacos , Aorta/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Cães , Feminino , Imidazóis/química , Imidazóis/farmacologia , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Naftalenos/química , Naftalenos/farmacologia , Coelhos , Ensaio Radioligante , Ratos , Receptores Adrenérgicos alfa 1 , Baço/efeitos dos fármacos , Baço/fisiologia , Relação Estrutura-Atividade , Sulfonamidas/química , Sulfonamidas/farmacologia , Tetra-Hidronaftalenos/química , Tetra-Hidronaftalenos/farmacologia , Uretra/efeitos dos fármacos , Uretra/fisiologia , Ducto Deferente/efeitos dos fármacos , Ducto Deferente/fisiologia
14.
J Empir Res Hum Res Ethics ; 7(5): 30-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23324201

RESUMO

In this paper, we draw on the authors' collective experiences as qualitative researchers undergoing research ethics reviews. We highlight specific areas within our standard national guidelines that support qualitative research. Using case examples, we illustrate how diverse interpretations of these guidelines can be inconsistent and problematic for qualitative researchers. We outline recommendations for transparency, reciprocity, and streamlining of the review process. It is our hope that adoption of these recommendations will lead to a more collegial evaluative process, thereby contributing to the advancement of knowledge.


Assuntos
Comitês de Ética em Pesquisa , Ética em Pesquisa , Guias como Assunto , Pesquisa Qualitativa , Pesquisadores/ética , Humanos
15.
Eur J Pharmacol ; 684(1-3): 87-94, 2012 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-22504024

RESUMO

Histamine H(3) receptor antagonists have been widely reported to improve performance in preclinical models of cognition, but more recently efficacy in pain models has also been described. Here, A-960656 ((R)-2-(2-(3-(piperidin-1-yl)pyrrolidin-1-yl)benzo[d]thiazol-6-yl)pyridazin-3(2H)-one) was profiled as a new structural chemotype. A-960656 was potent in vitro in histamine H(3) receptor binding assays (rat K(i)=76 nM, human K(i)=21 nM), and exhibited functional antagonism in blocking agonist-induced [(35)S]GTPγS binding (rat H(3) K(b)=107 nM, human H(3) K(b)=22 nM), and was highly specific for H(3) receptors in broad screens for non-H(3) sites. In a spinal nerve ligation model of neuropathic pain in rat, oral doses of 1 and 3mg/kg were effective 60 min post dosing with an ED(50) of 2.17 mg/kg and a blood EC(50) of 639 ng/ml. In a model of osteoarthritis pain, oral doses of 0.1, 0.3, and 1mg/kg were effective 1h post dosing with an ED(50) of 0.52 mg/kg and a blood EC(50) of 233 ng/ml. The antinociceptive effect of A-960656 in both pain models was maintained after sub-chronic dosing up to 12 days. A-960656 had excellent rat pharmacokinetics (t(1/2)=1.9h, 84% oral bioavailability) with rapid and efficient brain penetration, and was well tolerated in CNS behavioral safety screens. In summary, A-960656 has properties well suited to probe the pharmacology of histamine H(3) receptors in pain. Its potency and efficacy in animal pain models provide support to the notion that histamine H(3) receptor antagonists are effective in attenuating nociceptive processes.


Assuntos
Benzotiazóis/farmacologia , Antagonistas dos Receptores Histamínicos H3/farmacologia , Neuralgia/tratamento farmacológico , Osteoartrite/tratamento farmacológico , Piridazinas/farmacologia , Receptores Histamínicos H3/metabolismo , Animais , Benzotiazóis/efeitos adversos , Benzotiazóis/metabolismo , Benzotiazóis/farmacocinética , Permeabilidade da Membrana Celular , Inibidores das Enzimas do Citocromo P-450 , Modelos Animais de Doenças , Cães , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Células HEK293 , Coração/efeitos dos fármacos , Antagonistas dos Receptores Histamínicos H3/efeitos adversos , Antagonistas dos Receptores Histamínicos H3/metabolismo , Antagonistas dos Receptores Histamínicos H3/farmacocinética , Humanos , Masculino , Osteoartrite do Joelho/tratamento farmacológico , Piridazinas/efeitos adversos , Piridazinas/metabolismo , Piridazinas/farmacocinética , Ratos , Ratos Sprague-Dawley , Especificidade por Substrato
17.
Eur J Pharmacol ; 601(1-3): 8-15, 2008 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-18977214

RESUMO

We have recently identified three splice isoforms of the histamine H(3) receptor in multiple brain regions of cynomolgus monkey (Macaca fascicularis). Two of the novel isoforms displayed a deletion in the third intracellular loop (H(3)(413) and H(3)(410)), the third isoform H(3)(335) displayed a deletion in the i3 intracellular loop and a complete deletion of the putative fifth transmembrane domain TM5. We have confirmed by RT-PCR the expression of full-length H(3)(445) mRNA as well as H(3)(413), H(3)(410), and H(3)(335) splice isoform mRNA in multiple monkey brain regions including the frontal, parietal and occipital cortex, parahippocampal gyrus, hippocampus, amygdala, caudate nucleus, putamen, thalamus, hypothalamus, and cerebellum. The full-length isoform H(3)(445) was predominant in all of the regions tested, followed by H(3)(335), with the H(3)(413) and H(3)(410) being of low abundance. When expressed in C6 cells, H(3)(445), H(3)(413), and H(3)(410) exhibit high affinity binding to the agonist ligand [(3)H]-(N)-alpha-methylhistamine with respective pK(D) values of 9.7, 9.7, and 9.6. As expected, the H(3)(335) isoform did not display any saturable binding with [(3)H]-(N)-alpha-methylhistamine. The histamine H(3) receptor agonists histamine, (R)-alpha-methylhistamine, imetit and proxyfan were able to activate calcium mobilization responses through H(3)(445), H(3)(413) and H(3)(410) receptors when they were co-expressed with the chimeric G alpha(qi5)-protein in HEK293 cells, while no response was elicited in cells expressing the H(3)(335) isoform. The existence of multiple H(3) receptor splice isoforms across species raises the possibility that isoform specific properties including ligand affinity, signal transduction coupling, and brain localization may differentially contribute to observed in vivo effects of histamine H(3) receptor antagonists.


Assuntos
Expressão Gênica , RNA Mensageiro/metabolismo , Receptores Histamínicos H3/metabolismo , Animais , Encéfalo/metabolismo , Linhagem Celular , Clonagem Molecular , Agonistas dos Receptores Histamínicos/farmacologia , Humanos , Ligantes , Macaca fascicularis , Masculino , Ligação Proteica , Isoformas de Proteínas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Especificidade da Espécie
18.
J Med Chem ; 51(22): 7094-8, 2008 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-18983139

RESUMO

cis-4-(Piperazin-1-yl)-5,6,7a,8,9,10,11,11a-octahydrobenzofuro[2,3-h]quinazolin-2-amine, 4 (A-987306) is a new histamine H(4) antagonist. The compound is potent in H(4) receptor binding assays (rat H(4), K(i) = 3.4 nM, human H(4) K(i) = 5.8 nM) and demonstrated potent functional antagonism in vitro at human, rat, and mouse H(4) receptors in cell-based FLIPR assays. Compound 4 also demonstrated H(4) antagonism in vivo in mice, blocking H(4)-agonist induced scratch responses, and showed anti-inflammatory activity in mice in a peritonitis model. Most interesting was the high potency and efficacy of this compound in blocking pain responses, where it showed an ED(50) of 42 mumol/kg (ip) in a rat post-carrageenan thermal hyperalgesia model of inflammatory pain.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Benzofuranos/farmacologia , Hiperalgesia/tratamento farmacológico , Dor/prevenção & controle , Quinazolinas/farmacologia , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Benzofuranos/síntese química , Benzofuranos/química , Carragenina , Modelos Animais de Doenças , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Humanos , Hiperalgesia/induzido quimicamente , Ligantes , Camundongos , Estrutura Molecular , Dor/fisiopatologia , Peritonite/tratamento farmacológico , Quinazolinas/síntese química , Quinazolinas/química , Ratos , Receptores Histamínicos , Receptores Histamínicos H4 , Estereoisomerismo , Relação Estrutura-Atividade
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