RESUMO
The renal outer medullary potassium (ROMK) channel mediates potassium recycling and facilitates sodium reabsorption through the Na+/K+/2Cl- cotransporter in the loop of Henle and potassium secretion at the cortical collecting duct. Evidence from the phenotype of humans and rodents with functional ROMK deficiency supports the contention that selective ROMK inhibitors (ROMKi) will represent a novel diuretic with potential of therapeutic benefit for hypertension. ROMKi have recently been synthesized by Merck & Co, Inc. The present studies were designed to examine the effects of ROMKi B on systemic hemodynamics, renal function and structure, and vascular function in Dahl salt-sensitive rats. Four experimental groups-control, high-salt diet alone; ROMKi B 3 mg·kg-1·d-1; ROMKi B 10 mg·kg-1·d-1; and hydrochlorothiazide 25 mg·kg-1·d-1-were included in prophylactic (from week 1 to week 9 on high-salt diet) and therapeutic studies (from week 5 to week 9 on high-salt diet), respectively. ROMKi B produced sustained blood pressure reduction and improved renal and vascular function and histological alterations induced by a high-salt diet. ROMKi B was superior to hydrochlorothiazide at reducing blood pressure. Furthermore, ROMKi B provided beneficial effects on both the plasma lipid profile and bone mineral density. Chronic ROMK inhibition not only prevented but also reversed the development of hypertension and end-organ damage in Dahl salt-sensitive rats. Our findings suggest a potential utility of ROMKi B as a novel antihypertensive agent, particularly for the treatment of the salt-sensitive hypertension patient population.
Assuntos
Injúria Renal Aguda/prevenção & controle , Pressão Sanguínea , Hipertensão/prevenção & controle , Medula Renal/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/antagonistas & inibidores , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/fisiopatologia , Animais , Biomarcadores/urina , Modelos Animais de Doenças , Taxa de Filtração Glomerular , Hipertensão/metabolismo , Medula Renal/efeitos dos fármacos , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Ratos , Ratos Endogâmicos DahlRESUMO
BACKGROUND: Glucagon-like peptide 1 (GLP-1) analogs and dipeptidyl peptidase-4 (DPP4) inhibitors are a newer class of antidiabetics named as incretin-based therapy. In addition to the homeostatic control of glucose, the incretin-based therapy has shown beneficial effects on the cardiovascular system in preclinical and clinical studies. However, there is limited information on their renal effects. To this end, we assessed the acute hemodynamic and renal effects of a GLP-1 analog, Liraglutide, and a DPP4 inhibitor, MK-0626. METHODS: Experiments were performed in anesthetized male Sprague-Dawley rats. Three ascending doses of Liraglutide (3, 9, and 27 nmol/kg/h) or MK-0626 (1 mg/kg) with or without GLP-1 peptide (2.4, 4.8, or 9.6 pmol/kg/min) were administered. Blood pressure (BP) and heart rate (HR) were recorded from an indwelling catheter. Glomerular filtration rate (GFR) and renal blood flow (RBF) were assessed by inulin and para-aminohippurate clearance, respectively. Renal excretory function was assessed in metabolic studies. RESULTS: Both Liraglutide and MK-0626 plus GLP-1 evoked significant diuretic and natriuretic responses and increased GFR. MK-0626 alone increased RBF. Liraglutide at 27 nmol//kg/h and MK-0626 plus GLP-1 at 9.6 pmol/kg/min also increased HR, whereas BP was not affected. CONCLUSION: The results of the present study demonstrated that a GLP-1 analog and a DPP4 inhibitor may have beneficial effects on renal sodium and water handling. Additionally, the DPP4 inhibitor, MK-0626, favorably affects renal hemodynamics by increasing RBF. However, exceedingly high levels of GLP-1 receptor agonists may adversely affect the cardiovascular system in acute setting, as demonstrated by an acute increase in HR.
Assuntos
Pressão Sanguínea/efeitos dos fármacos , Inibidores da Dipeptidil Peptidase IV/farmacologia , Taxa de Filtração Glomerular/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Incretinas/farmacologia , Liraglutida/farmacologia , Circulação Renal/efeitos dos fármacos , Triazóis/farmacologia , Animais , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Hemodinâmica/efeitos dos fármacos , Rim/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Lowering of serum low-density lipoprotein cholesterol (LDL-C) levels remains the primary aim of lipid management. Much progress has been made in reducing rates of cardiovascular disease morbidity and mortality, largely through increased awareness of lipid-lowering therapies and particularly through the use of high-efficacy LDL-C-lowering HMG-CoA reductase inhibitors (statins). While statins have been effective in reducing cardiovascular disease risk, many patients do not adequately achieve guideline-recommended LDL-C goals and may benefit from additional cholesterol management therapies. Low serum levels of high-density lipoprotein cholesterol (HDL-C) are considered another important determinant of cardiovascular disease risk, and increased serum HDL-C levels have been shown to be associated with reductions in the incidence of cardiovascular disease. One approach toward raising serum HDL-C levels is the inhibition of cholesteryl ester-transfer protein (CETP), a plasma protein that promotes the transfer of cholesteryl ester from HDL particles and other lipoprotein fractions to pro-atherogenic apolipoprotein B-containing lipoproteins. The inhibition of this protein raises HDL-C levels and also reduces LDL-C levels. The concept of raising HDL-C levels through pharmacological intervention of this target was validated in preclinical and clinical studies with torcetrapib, the first CETP inhibitor to be assessed in late-stage clinical trials. The large clinical outcomes trial, ILLUMINATE, was prematurely terminated due to other unexpected pharmacological effects of torcetrapib that led to an increased risk of cardiovascular events and deaths. Thus, the ultimate effect of CETP inhibition on cardiovascular disease outcomes remains to be determined. Other CETP inhibitors currently in development do not have the adverse effects of increased blood pressure and circulating levels of aldosterone shown to be structurally related to torcetrapib. Preclinical and pharmacology studies have shown that these CETP inhibitors are distinct compared with torcetrapib and lack the features related to its off-target pharmacology. These findings indicate that the off-target activities of torcetrapib are not necessarily class effects of CETP inhibitors. Recent clinical trials have shown that dalcetrapib, anacetrapib and evacetrapib, the most advanced of these compounds in development, effectively raise HDL-C levels and lower LDL-C in the absence of off-target activities. The results of these trials are encouraging within the limits of study size and duration and provide a rationale for conducting further studies, including large clinical outcomes trials to assess whether CETP inhibition can lead to cardioprotective effects. This review summarizes the data supporting the development of CETP inhibitors as HDL-C-raising therapy, including structure-activity relationships and preclinical and clinical pharmacology studies of known CETP inhibitors.
Assuntos
Anticolesterolemiantes/farmacologia , Doenças Cardiovasculares/prevenção & controle , Proteínas de Transferência de Ésteres de Colesterol/antagonistas & inibidores , Quinolinas/farmacologia , Anticolesterolemiantes/química , Doenças Cardiovasculares/tratamento farmacológico , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Humanos , Quinolinas/química , Fatores de Risco , Relação Estrutura-AtividadeRESUMO
We investigated the effects of chronic mineralocorticoid receptor blockade with eplerenone on the development and progression of hypertension and end organ damage in Dahl salt-sensitive rats. Eplerenone significantly attenuated the progressive rise in systolic blood pressure (SBP) (204 ± 3 vs. 179±3 mmHg, p < 0.05), reduced proteinuria (605.5 ± 29.6 vs. 479.7 ± 26.1 mg/24h, p < 0.05), improved injury scores of glomeruli, tubules, renal interstitium, and vasculature in Dahl salt-sensitive rats fed a high-salt diet. These results demonstrate that mineralocorticoid receptor antagonism provides target organ protection and attenuates the development of elevated blood pressure (BP) in a model of salt-sensitive hypertension.
Assuntos
Hipertensão Renal/tratamento farmacológico , Antagonistas de Receptores de Mineralocorticoides , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Cloreto de Sódio na Dieta/farmacologia , Espironolactona/análogos & derivados , Aldosterona/sangue , Animais , Pressão Sanguínea/efeitos dos fármacos , Doença Crônica , Creatinina/sangue , Modelos Animais de Doenças , Progressão da Doença , Eletrólitos/sangue , Eplerenona , Frequência Cardíaca/efeitos dos fármacos , Hipertensão Renal/patologia , Hipertensão Renal/fisiopatologia , Rim/efeitos dos fármacos , Rim/patologia , Rim/fisiologia , Masculino , Antagonistas de Receptores de Mineralocorticoides/sangue , Tamanho do Órgão , Ratos , Ratos Endogâmicos Dahl , Receptores de Mineralocorticoides/fisiologia , Espironolactona/sangue , Espironolactona/farmacologiaRESUMO
N-type calcium channels (Ca(v)2.2) have been shown to play a critical role in pain. A series of low molecular weight 2-aryl indoles were identified as potent Ca(v)2.2 blockers with good in vitro and in vivo potency.
Assuntos
Bloqueadores dos Canais de Cálcio/uso terapêutico , Canais de Cálcio Tipo N/metabolismo , Indóis/uso terapêutico , Dor/tratamento farmacológico , Animais , Bloqueadores dos Canais de Cálcio/farmacocinética , Bloqueadores dos Canais de Cálcio/farmacologia , Cães , Haplorrinos , Humanos , Indóis/farmacocinética , Indóis/farmacologia , RatosRESUMO
Biaryl cyclohexene carboxylic acids were discovered as full and potent niacin receptor (GPR109A) agonists. Compound 1e (MK-6892) displayed excellent receptor activity, good PK across species, remarkably clean off-target profiles, good ancillary pharmacology, and superior therapeutic window over niacin regarding the FFA reduction versus vasodilation in rats and dogs.
Assuntos
Ácidos Carboxílicos/farmacologia , Ácidos Cicloexanocarboxílicos/farmacologia , Cicloexenos/química , Descoberta de Drogas , Oxidiazóis/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Animais , Área Sob a Curva , Ligação Competitiva , Células CHO , Ácidos Carboxílicos/química , Ácidos Carboxílicos/farmacocinética , Cricetinae , Cricetulus , Ácidos Cicloexanocarboxílicos/química , Ácidos Cicloexanocarboxílicos/farmacocinética , Cães , Avaliação Pré-Clínica de Medicamentos , Ácidos Graxos não Esterificados/sangue , Humanos , Taxa de Depuração Metabólica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Químicos , Estrutura Molecular , Oxidiazóis/química , Oxidiazóis/farmacocinética , Ratos , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Relação Estrutura-Atividade , Vasodilatação/efeitos dos fármacosRESUMO
Improved methods for non-invasive in vivo assessment are needed to guide development of animal models of atherosclerosis and to evaluate target engagement and in vivo efficacy of new drugs. Using novel 3D-micro-ultrasound technology, we developed and validated a novel protocol for 3D acquisition and analysis of imaging to follow lesion progression in atherosclerotic mice. The carotid arteries of ApoE receptor knockout mice and normal control mice were imaged within the proximal 2mm from the aortic branch point. Plaque volume along that length was quantified using a semi-automated 3D segmentation algorithm. Volumes derived by this method were compared to those calculated using 3-D histology post-mortem. Bland-Altman comparison revealed close correlation between these two measures of plaque volume. Furthermore, using a segmentation technique that captures early positive and 33 week negative remodeling, we found evidence that plaque volume increases linearly over time. Each animal and each plaque served as its own control, allowing accurate comparison. The high fidelity anatomical registration of this protocol provides increased spatial resolution and therefore greater sensitivity for measurement of plaque wall size, an advance over 2-dimensional measures of intimal-medial-thickening. Further, 3-dimensional analysis ensures a point of registration that captures functional markers in addition to the standard structural markers that characterize experimental atherosclerosis. In conclusion, this novel imaging protocol provides a non-invasive, accurate surrogate marker for experimental atherosclerosis over the life of the entire lesion.
Assuntos
Doenças das Artérias Carótidas/diagnóstico por imagem , Artéria Carótida Primitiva/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Microscopia Acústica , Algoritmos , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Automação , Modelos Animais de Doenças , Progressão da Doença , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de TempoRESUMO
A series of betamethasone 17alpha-carbamates were designed, synthesized, and evaluated for their ability to dissociate the two main functions of the glucocorticoid receptor, that is, transactivation and transrepression, in rat cell lines. A number of alkyl substituted betamethasone 17alpha-carbamates were identified with excellent affinity for the glucocorticoid receptor (e.g., 7, GR IC(50) 5.1 nM) and indicated dissociated profiles in functional assays of transactivation (rat tyrosine aminotransferase, TAT, and rat glutamine synthetase, GS) and transrepression (human A549 cells, MMP-1 assay). Gratifyingly, the in-vivo profile of these compounds, for example, 7, also indicated potent anti-inflammatory activity with impaired effects on glucose, insulin, triglycerides, and body weight. Taken together, these results indicate that dissociated glucocorticoid receptor modulators can be identified in rodents.
Assuntos
Betametasona/análogos & derivados , Carbamatos/síntese química , Receptores de Glucocorticoides/metabolismo , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacocinética , Anti-Inflamatórios/farmacologia , Betametasona/síntese química , Betametasona/farmacocinética , Betametasona/farmacologia , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Carbamatos/química , Carbamatos/farmacocinética , Carbamatos/farmacologia , Glutamato-Amônia Ligase/metabolismo , Insulina/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Metaloproteinase 1 da Matriz/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Ratos , Receptores de Glucocorticoides/química , Triglicerídeos/sangue , Tirosina Transaminase/metabolismoRESUMO
Biaryl anthranilides are reported as potent and selective full agonists for the high affinity niacin receptor GPR109A. The SAR presented outlines approaches to reduce serum shift and both CYPCYP2C8 and CYP2C9 liabilities, while improving PK and maintaining excellent receptor activity. Compound 2i exhibited good in vivo antilipolytic efficacy while providing a significantly improved therapeutic index over vasodilation (flushing) with respect to niacin in the mouse model.
Assuntos
Receptores Acoplados a Proteínas G/agonistas , ortoaminobenzoatos/síntese química , Amidas/síntese química , Amidas/farmacocinética , Amidas/farmacologia , Animais , Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Ligação Competitiva , Células CHO , Cricetinae , Cricetulus , Citocromo P-450 CYP2C8 , Citocromo P-450 CYP2C9 , Humanos , Técnicas In Vitro , Camundongos , Microssomos Hepáticos/metabolismo , Ensaio Radioligante , Receptores Nicotínicos , Relação Estrutura-Atividade , ortoaminobenzoatos/farmacocinética , ortoaminobenzoatos/farmacologiaRESUMO
INTRODUCTION: GPR109A is the receptor mediating both the antilipolytic and vasodilatory effects of nicotinic acid. In order to develop agonists for GPR109A with improved therapeutic indices we have sought to optimize animal models that evaluate both nicotinic acid-mediated inhibition of lipolysis and stimulation of vasodilatation. The rat and the dog have previously been used to study the antilipolytic effects of nicotinic acid, but no optimal vasodilatation model exits in either species. METHODS: We have developed a vasodilatation model in the rat that measures changes in ear perfusion using laser Doppler flowmetry. In the dog, we have developed a model of vasodilatation measuring changes in red color values in the ear, using a spectrocolorimeter. Effects of GPR109A agonists on lipolysis were measured in both species after oral dosing of compounds, and measuring plasma levels of free fatty acids. RESULTS: In both rat and dog, GPR109A agonists induce dose- and time-dependent vasodilatation, similar to that observed in humans. Vasodilatation is inhibited in both species with cyclooxygenase inhibitors or a specific DP1 receptor antagonist, indicating that, as in man, nicotinic acid-induced vasodilatation in rats and dogs is mainly mediated by the release of PGD(2). DISCUSSION: Our results show that both rat and dog are useful models for the characterization of GPR109A agonists. A therapeutic index for GPR109A agonists can be calculated in either species.
Assuntos
Lipólise/efeitos dos fármacos , Agonistas Nicotínicos/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Vasodilatação/efeitos dos fármacos , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacologia , Cães , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Monitoramento de Medicamentos/métodos , Ácidos Graxos não Esterificados/sangue , Hipolipemiantes/administração & dosagem , Hipolipemiantes/farmacologia , Indometacina/administração & dosagem , Indometacina/farmacologia , Concentração Inibidora 50 , Injeções Subcutâneas , Masculino , Modelos Animais , Niacina/administração & dosagem , Niacina/farmacologia , Agonistas Nicotínicos/administração & dosagem , Pirazinas/administração & dosagem , Pirazinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Nicotínicos/metabolismoRESUMO
Chemistry was developed to synthesize the title series of compounds. The ability of these novel ligands to bind to the glucocorticoid receptor was investigated. These compounds were also tested in a series of functional assays and some were found to display the profile of a dissociated glucocorticoid. The SAR of the 6,5-bicyclic series differed markedly from the previously reported 6,6-series. Molecular modeling studies were employed to understand the conformational differences between the two series of compounds, which may explain their divergent activity. Two compounds were profiled in vivo and shown to reduce inflammation in a mouse model. An active metabolite is suspected in one case.
Assuntos
Antineoplásicos/farmacologia , Compostos Bicíclicos com Pontes/química , Glucocorticoides/química , Pirazóis/química , Receptores de Glucocorticoides/efeitos dos fármacos , Animais , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Humanos , Ligantes , Camundongos , Modelos Químicos , Modelos Moleculares , Receptores de Glucocorticoides/metabolismo , Relação Estrutura-AtividadeRESUMO
The sphingosine-1-phosphate (S1P) receptor agonist, phosphorylated FTY720 (FTY-P), causes lymphopenia, lymphocyte sequestration in mesenteric lymph nodes (MLNs), and immunosuppression. Using multiple techniques to analyze MLN cells harvested from mice treated with S1P receptor agonists, we saw a redistribution of lymphocytes out of nodal sinuses and an expansion of follicles. Although changes in circulating monocytes were not observed with overnight exposure to FTY720, we saw a significant increase in S1P receptor 1 (S1P1)-expressing CD68+ macrophages in subcapsular sinuses of FTY-P-treated MLNs. This was confirmed by quantitative analysis of F4/80+ cells in MLN suspensions. The sinus volume and number of S1P1-positive cells within sinuses were also increased by FTY-P. High endothelial venules and lymphatic endothelium expressed high levels of S1P1, and treatment with FTY-P resulted in intense staining and colocalization of CD31, beta-catenin, and zona occludens 1 in junctions between sinus cells. Transmission electron microscopy showed that FTY-P greatly reduced lymphocyte microvilli and increased cell-cell contacts in the parenchyma. Immunoelectron microscopy revealed that intranodal lymphocytes lacked surface expression of S1P1, whereas S1P1 was evident on the surface and within the cytoplasm of macrophages, endothelial cells, and stromal cells. This subcellular pattern of intranodal receptor distribution was unchanged by treatment with FTY-P. We conclude that S1P1 agonists have profound effects on macrophages and endothelial cells, in addition to inducing lymphopenia.
Assuntos
Imunossupressores/farmacologia , Linfonodos/imunologia , Linfócitos/imunologia , Macrófagos/imunologia , Propilenoglicóis/farmacologia , Receptores de Lisoesfingolipídeo/imunologia , Animais , Comunicação Celular/imunologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/imunologia , Células Endoteliais/ultraestrutura , Endotélio Linfático/efeitos dos fármacos , Endotélio Linfático/ultraestrutura , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/ultraestrutura , Feminino , Cloridrato de Fingolimode , Imunofluorescência , Linfonodos/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Mesentério/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Microscopia Imunoeletrônica , Fosforilação , Receptores de Lisoesfingolipídeo/efeitos dos fármacos , Receptores de Lisoesfingolipídeo/metabolismo , Esfingosina/análogos & derivados , Junções Íntimas/imunologia , Junções Íntimas/ultraestruturaRESUMO
A novel series of selective ligands for the human glucocorticoid receptor is described. Structure-activity studies focused on variation of B-ring size, ketal ring size, and ketal substitution. These analogs were found to be potent and selective ligands for GR and have partial agonist profiles in functional assays for transactivation (TAT, GS) and transrepression (IL-6). Of these compounds, 27, 28, and 35 were evaluated further in a mouse LPS-induced TNF-alpha secretion model. Compound 28 had an ED(50) of 14.1 mg/kg compared with 0.5 mg/kg for prednisolone in the same assay.
Assuntos
Receptores de Glucocorticoides/metabolismo , Animais , Células Cultivadas , Humanos , Técnicas In Vitro , Ligantes , CamundongosRESUMO
A series of novel ligands for the glucocorticoid receptor containing two heterocycles were synthesized. These compounds were investigated for a dissociative profile using transrepression and transactivation assays. Several compounds were tested in vivo and showed the ability to reduce inflammation in a mouse.
Assuntos
Glucocorticoides/química , Compostos Heterocíclicos/química , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Linhagem Celular , Glucocorticoides/administração & dosagem , Glucocorticoides/farmacologia , Compostos Heterocíclicos/administração & dosagem , Compostos Heterocíclicos/farmacologia , Humanos , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossínteseRESUMO
A series of 2-aryloxy-2-methyl-propionic acid compounds and related analogues were designed, synthesized, and evaluated for their PPAR agonist activities. 2-[(5,7-Dipropyl-3-trifluoromethyl)-benzisoxazol-6-yloxy]-2-methylpropionic acid (4) was identified as a PPARalpha/gamma dual agonist with relative PPARalpha selectivity and demonstrated potent efficacy in lowering both glucose and lipids in animal models without causing body weight gain. The PPARalpha activity of 4 appeared to have played a significant role in lowering glucose levels in db/db mice.
Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hiperlipidemias/tratamento farmacológico , Hipoglicemiantes/síntese química , Hipolipemiantes/síntese química , Isoxazóis/síntese química , PPAR alfa/agonistas , PPAR gama/agonistas , Propionatos/síntese química , Células 3T3-L1 , Animais , Glicemia/efeitos dos fármacos , Células COS , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Chlorocebus aethiops , Colesterol/sangue , Cães , Proteínas de Ligação a Ácido Graxo , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Hipolipemiantes/química , Hipolipemiantes/farmacologia , Isoxazóis/química , Isoxazóis/farmacologia , Camundongos , Camundongos Obesos , Propionatos/química , Propionatos/farmacologia , RNA Mensageiro/biossíntese , Ensaio Radioligante , Relação Estrutura-Atividade , Ativação Transcricional , Triglicerídeos/sangue , Aumento de PesoRESUMO
The use of chronic glucocorticoid (GC) therapy for the treatment of inflammatory diseases is limited by associated metabolic side effects, including muscle atrophy. Therefore, selective glucocorticoid receptor-(GR)-binding ligands that maintain anti-inflammatory activity and demonstrate diminished side-effect profiles would have great therapeutic utility. In this work, we use Taqman PCR and ELISA methods to show that GCs can inhibit basal, and lipopolysaccharide (LPS)-stimulated levels of cytokines IL-6 and TNFalpha, and also the chemokine MCP-1 in a non-inflammatory system such as primary human skeletal muscle cells. In the murine C2C12 skeletal muscle cell line we observe a similar effect of GCs on IL-6 and MCP-1; however, in contrast to previous reports, we observe a time-dependent repression of TNFalpha. Furthermore, in skeletal muscle cells, concomitant with cytokine repression, GCs transcriptionally induce glutamine synthetase (GS), a marker for muscle wasting, in an LPS independent manner. Similarly, administration of dexamethasone to mice, previously administered LPS, results in an increase in GS and an inhibition of TNFalpha and MCP-1 in skeletal muscle tissue. Thus, skeletal muscle cells and tissues present a novel system for the identification of selective GR-binding ligands, which simultaneously inhibit cytokine expression in the absence of GS induction.
Assuntos
Dexametasona/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Músculo Esquelético/metabolismo , Ativação Transcricional/efeitos dos fármacos , Animais , Sequência de Bases , Linhagem Celular , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Feminino , Interleucina-6/metabolismo , Camundongos , Músculo Esquelético/citologia , Reação em Cadeia da PolimeraseRESUMO
A novel series of selective ligands for the human glucocorticoid receptor (hGR) are described. Preliminary structure-activity relationships were focused on substitution at C-1 and indicated a preference for 3-, 4-, and 5-substituted aromatic and benzylic groups. The resulting analogues, e.g., 18 and 34, exhibited excellent affinity for hGR (IC(50) 1.9 nM and 2.8 nM, respectively) and an interesting partial agonist profile in functional assays of transactivation (tyrosine aminotransferase, TAT, and glutamine synthetase, GS) and transrepression (IL-6). The most potent compounds described in this study were the tertiary alcohol derivatives 21 and 25. These candidates showed highly efficacious IL-6 inhibition versus dexamethasone. The thiophenyl analogue 25 was evaluated in vivo in the mouse LPS challenge model and showed an ED(50) = 4.0 mg/kg, compared to 0.5 mg/kg for prednisolone in the same assay.
Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Indazóis/síntese química , Pirazóis/síntese química , Receptores de Glucocorticoides/metabolismo , Tiofenos/síntese química , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Linhagem Celular , Cristalografia por Raios X , Indução Enzimática , Feminino , Glutamato-Amônia Ligase/biossíntese , Glutamato-Amônia Ligase/genética , Humanos , Indazóis/química , Indazóis/farmacologia , Interleucina-6/antagonistas & inibidores , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Conformação Molecular , Isoformas de Proteínas/agonistas , Isoformas de Proteínas/metabolismo , Pirazóis/química , Pirazóis/farmacologia , Ensaio Radioligante , Receptores de Glucocorticoides/agonistas , Estereoisomerismo , Relação Estrutura-Atividade , Tiofenos/química , Tiofenos/farmacologia , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Tirosina Transaminase/biossíntese , Tirosina Transaminase/genéticaRESUMO
Aryldihydropyridazinones and aryldimethylpyrazolones with 2-benzyl vinylogous amide substituents have been identified as potent PDE3B subtype selective inhibitors. Dihydropyridazinone 8a (PDE3B IC(50)=0.19 nM, 3A IC(50)=1.3 nM) was selected for in vivo evaluation of lipolysis induction, metabolic rate increase, and cardiovascular effects.
Assuntos
3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Inibidores de Fosfodiesterase/síntese química , Inibidores de Fosfodiesterase/farmacologia , Piridazinas/síntese química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3 , Desenho de Fármacos , Cinética , Piridazinas/farmacologia , Relação Estrutura-Atividade , Compostos de Vinila/síntese química , Compostos de Vinila/farmacologiaRESUMO
A new class of O-arylmandelic acid PPAR agonists show excellent anti-hyperglycemic efficacy in a db/db mouse model of DM2. These PPARalpha-weighted agonists do not show the typical PPARgamma associated side effects of BAT proliferation and cardiac hypertrophy in a rat tolerability assay.
Assuntos
Ácidos Mandélicos/farmacologia , Receptores Citoplasmáticos e Nucleares/agonistas , Fatores de Transcrição/agonistas , Animais , Ácidos Mandélicos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Ratos , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Transcrição/metabolismoRESUMO
Mice lacking the chemokine receptor chemotactic cytokine receptor 2 (CCR2) have a marked attenuation of monocyte recruitment in response to various inflammatory stimuli and a reduction of inflammatory lesions in models of demyelinating disease. In the present study, we compared nociceptive responses in inflammatory and neuropathic models of pain in CCR2 knockout and wild-type mice. In acute pain tests, responses were equivalent in CCR2 knockout and wild-type mice. In models of inflammatory pain, CCR2 knockout mice showed a 70% reduction in phase 2 of the intraplantar formalin-evoked pain response but only a modest (20-30%) and nonsignificant reduction of mechanical allodynia after intraplantar Freund's adjuvant (CFA). In a model of neuropathic pain, the development of mechanical allodynia was totally abrogated in CCR2 knockout mice. CFA administration induced marked up-regulation of CCR2 mRNA in the skin and a moderate increase in the sciatic nerve and dorsal root ganglia (DRG). In response to nerve ligation, persistent and marked up-regulation of CCR2 mRNA was evident in the nerve and DRG. Disruption of Schwann cells in response to nerve lesion resulted in infiltration of CCR2-positive monocytes/macrophages not only to the neuroma but also to the DRG. Chronic pain also resulted in the appearance of activated CCR2-positive microglia in the spinal cord. Collectively, these data suggest that the recruitment and activation of macrophages and microglia peripherally and in neural tissue may contribute to both inflammatory and neuropathic pain states. Accordingly, blockade of the CCR2 receptor may provide a novel therapeutic modality for the treatment of chronic pain.