RESUMO
The maintenance of cellular function relies on the close regulation of adenosine triphosphate (ATP) synthesis and hydrolysis. ATP hydrolysis by mitochondrial ATP Synthase (CV) is induced by loss of proton motive force and inhibited by the mitochondrial protein ATPase inhibitor (ATPIF1). The extent of CV hydrolytic activity and its impact on cellular energetics remains unknown due to the lack of selective hydrolysis inhibitors of CV. We find that CV hydrolytic activity takes place in coupled intact mitochondria and is increased by respiratory chain defects. We identified (+)-Epicatechin as a selective inhibitor of ATP hydrolysis that binds CV while preventing the binding of ATPIF1. In cells with Complex-III deficiency, we show that inhibition of CV hydrolytic activity by (+)-Epichatechin is sufficient to restore ATP content without restoring respiratory function. Inhibition of CV-ATP hydrolysis in a mouse model of Duchenne Muscular Dystrophy is sufficient to improve muscle force without any increase in mitochondrial content. We conclude that the impact of compromised mitochondrial respiration can be lessened using hydrolysis-selective inhibitors of CV.
Assuntos
Trifosfato de Adenosina , Mitocôndrias , Camundongos , Animais , Trifosfato de Adenosina/metabolismo , Mitocôndrias/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Proteínas/metabolismo , Homeostase , HidróliseRESUMO
INTRODUCTION: We conducted an open-label study to examine the effects of the flavonoid (-)-epicatechin in seven ambulatory adult patients with Becker muscular dystrophy (BMD). METHODS: Seven participants received (-)-epicatechin 50 mg twice per day for 8 weeks. Pre- and postprocedures included biceps brachii biopsy to assess muscle structure and growth-relevant endpoints by western blotting, mitochondria volume measurement, and cristae abundance by electron microscopy, graded exercise testing, and muscle strength and function tests. RESULTS: Western blotting showed significantly increased levels of enzymes modulating cellular bioenergetics (liver kinase B1 and 5'-adenosine monophosphate-activated protein kinase). Peroxisome proliferator-activated receptor gamma coactivator-1alpha, a transcriptional coactivator of genes involved in mitochondrial biogenesis and cristae-associated mitofilin levels, increased as did cristae abundance. Muscle and plasma follistatin increased significantly while myostatin decreased. Markers of skeletal muscle regeneration myogenin, myogenic regulatory factor-5, myoblast determination protein 1, myocyte enhancer factor-2, and structure-associated proteins, including dysferlin, utrophin, and intracellular creatine kinase, also increased. Exercise testing demonstrated decreased heart rate, maximal oxygen consumption per kilogram, and plasma lactate levels at defined workloads. Tissue saturation index improved in resting and postexercise states. DISCUSSION: (-)-Epicatechin, an exercise mimetic, appears to have short-term positive effects on tissue biomarkers indicative of mitochondrial biogenesis and muscle regeneration, and produced improvements in graded exercise testing parameters in patients with BMD.
Assuntos
Catequina/uso terapêutico , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/tratamento farmacológico , Adulto , Biópsia , Western Blotting , Creatina Quinase/metabolismo , Disferlina/metabolismo , Teste de Esforço , Folistatina/metabolismo , Frequência Cardíaca , Humanos , Ácido Láctico/sangue , Fatores de Transcrição MEF2/metabolismo , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Mitocôndrias/ultraestrutura , Proteínas Mitocondriais/metabolismo , Tamanho Mitocondrial , Proteínas Musculares/metabolismo , Força Muscular , Músculo Esquelético/fisiopatologia , Músculo Esquelético/ultraestrutura , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/patologia , Distrofia Muscular de Duchenne/fisiopatologia , Proteína MyoD/metabolismo , Fator Regulador Miogênico 5/metabolismo , Miogenina/metabolismo , Miostatina/metabolismo , Biogênese de Organelas , Consumo de Oxigênio , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Regeneração , Utrofina/metabolismoRESUMO
BACKGROUND: (+)-Epicatechin (EPI) induces mitochondrial biogenesis and antioxidant metabolism in muscle fibers and neurons. We aimed to evaluate safety and efficacy of (+)-EPI in pediatric subjects with Friedreich's ataxia (FRDA). METHODS: This was a phase II, open-label, baseline-controlled single-center trial including 10 participants ages 10 to 22 with confirmed FA diagnosis. (+)-EPI was administered orally at 75 mg/d for 24 weeks, with escalation to 150 mg/d at 12 weeks for subjects not showing improvement of neuromuscular, neurological or cardiac endpoints. Neurological endpoints were change from baseline in Friedreich's Ataxia Rating Scale (FARS) and 8-m timed walk. Cardiac endpoints were changes from baseline in left ventricular (LV) structure and function by cardiac magnetic resonance imaging (MRI) and echocardiogram, changes in cardiac electrophysiology, and changes in biomarkers for heart failure and hypertrophy. RESULTS: Mean FARS/modified (m)FARS scores showed nonstatistically significant improvement by both group and individual analysis. FARS/mFARS scores improved in 5/9 subjects (56%), 8-m walk in 3/9 (33%), 9-peg hole test in 6/10 (60%). LV mass index by cardiac MRI was significantly reduced at 12 weeks (P = .045), and was improved in 7/10 (70%) subjects at 24 weeks. Mean LV ejection fraction was increased at 24 weeks (P = .008) compared to baseline. Mean maximal septal thickness by echocardiography was increased at 24 weeks (P = .031). There were no serious adverse events. CONCLUSION: (+)-EPI was well tolerated over 24 weeks at up to 150 mg/d. Improvement was observed in cardiac structure and function in subset of subjects with FRDA without statistically significant improvement in primary neurological outcomes. SYNOPSIS: A (+)-epicatechin showed improvement of cardiac function, nonsignificant reduction of FARS/mFARS scores, and sustained significant upregulation of muscle-regeneration biomarker follistatin.
Assuntos
Antioxidantes/administração & dosagem , Catequina/administração & dosagem , Ataxia de Friedreich/tratamento farmacológico , Coração/diagnóstico por imagem , Adolescente , Criança , Ecocardiografia , Feminino , Ataxia de Friedreich/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença , Resultado do Tratamento , CaminhadaRESUMO
Currently, there is great interest in identifying endogenous (i.e. physiological) stimulators of mitochondrial biogenesis (MB), in particular, those that may mediate the effects of exercise. The molecular size of the cacao flavanols (epicatechin and catechin) highly resembles that of sterols and epicatechin has been reported to activate cells surface receptors leading to the stimulation of MB in endothelial and skeletal muscle cells translating into enhanced exercise capacity. We therefore hypothesize, that epicatechin may be acting as a structural mimic of an as yet unknown sterol capable of stimulating MB. We developed a new synthetic process for obtaining enantiomerically pure preparations of (-)-epicatechin and (+)-epicatechin. Applying spatial analytics and molecular modeling, we found that the two isoforms of epicatechin, (-) and (+), have a structural resemblance to 11-ß-hydroxypregnenolone, a sterol with no previously described biological activity. As reported in this proof-of-concept study performed in primary cultures of endothelial and muscle cells, 11-ß-hydroxypregnenolone is one of the most potent inducers of MB as significant activity can be detected at femtomolar levels. The relative potency of (-)/(+)-epicatechin isoforms and on inducing MB correlates with their degree of spatial homology towards the 11-ß-hydroxypregnenolone. On the basis of these results, the detailed in vivo characterization of the potential for these sterols to act as endogenous modulators of MB is warranted.
Assuntos
Catequina/química , Catequina/farmacologia , Mimetismo Molecular , Biogênese de Organelas , Esteróis/química , Esteróis/farmacologia , Animais , Bovinos , Linhagem Celular , Células Cultivadas , Camundongos , Modelos Moleculares , EstereoisomerismoRESUMO
Over activation of the PI3K/Akt/mTOR pathway is found in most cancer tumor types. Controlled regulation of this pathway using PI3K inhibitors can provide therapeutic significance in cancer treatment. Herein, we report the synthesis and evaluation of pyrrolotriazine based novel small molecules as pan-PI3K inhibitors. The SAR studies based on in vitro potency along with microsomal metabolic stability screening, identified 18 as a preclinical lead found to be suitable for in vivo evaluation. The identified lead was also found to be a selective inhibitor of PI3K isoforms and mTOR when screened across a panel of 23 homologous kinases.
Assuntos
Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/síntese química , Triazinas/química , Sítios de Ligação , Domínio Catalítico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Humanos , Microssomos/metabolismo , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Ligação Proteica , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Triazinas/metabolismo , Triazinas/farmacologiaRESUMO
Consumption of (-)-epicatechin (Epi), a cacao flavanol improves cognition. The aim was to compare the effects of (-)-Epi or its stereoisomer (+)-Epi on mouse frontal cortex-dependent short-term working memory and modulators of neurogenesis. Three-month-old male mice (n = 7 per group) were provided by gavage either water (vehicle; Veh), (-)-Epi, at 1 mg kg-1 or (+)-Epi at 0.1 mg per kg of body weight for 15 days. After treatment, spontaneous alternation was evaluated by Y-maze. Brain frontal cortex was isolated for nitrate/nitrite measurements, Western blotting for nerve growth factor (NGF), microtubule associated protein 2 (MAP2), endothelial and neuronal nitric oxide synthase (eNOS and nNOS) and immunohistochemistry for neuronal specific protein (NeuN), doublecortin (DCX), capillary (CD31) and neurofilaments (NF200). Results demonstrate the stimulatory capacity of (-)-Epi and (+)-Epi on markers of neuronal proliferation as per increases in immunoreactive cells for NeuN (74 and 120% respectively), DCX (70 and 124%) as well as in NGF (34.4, 63.6%) and MAP2 (41.8, 63.8%). Capillary density yielded significant increases with (-)-Epi (â¼80%) vs. (+)-Epi (â¼160%). CD31 protein levels increased with (-)-Epi (â¼70%) and (+)-Epi (â¼140%). Effects correlated with nitrate/nitrite stimulation by (-)-Epi and (+)-Epi (110.2, 246.5%) and enhanced eNOS phosphorylation (Ser1177) with (-)-Epi and (+)-Epi (21.4, 41.2%) while nNOS phosphorylation only increased with (+)-Epi (18%). Neurofilament staining was increased in (-)-Epi by 135.6 and 84% with (+)-Epi. NF200 increased with (-)-Epi (116%) vs. (+)-Epi (84.5%). Frontal cortex-dependent short-term spatial working improved with (-)-Epi and (+)-Epi (15, 13%). In conclusion, results suggest that both enantiomers, but more effectively (+)-Epi, upregulate neurogenesis markers likely through stimulation of capillary formation and NO triggering, improvements in memory.
Assuntos
Catequina/farmacologia , Lobo Frontal/fisiologia , Memória de Curto Prazo/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Animais , Biomarcadores/análise , Química Encefálica , Cacau/química , Catequina/análise , Proliferação de Células/efeitos dos fármacos , Proteína Duplacortina , Lobo Frontal/irrigação sanguínea , Lobo Frontal/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/fisiologia , Óxido Nítrico/metabolismo , EstereoisomerismoRESUMO
The design and synthesis of a new class of p38alpha MAP kinase inhibitors based on 4-fluorobenzylpiperidine heterocyclic oxalyl amides are described. Many of these compounds showed low-nanomolar activities in p38alpha enzymatic and cell-based cytokine TNFalpha production inhibition assays. The optimal linkers between the piperidine and the oxalyl amide were found to be [6,5] fused ring heterocycles. Substituted indoles and azaindoles were favored structural motifs in the cellular assay.
Assuntos
Amidas/química , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Oxalatos/química , Piperidinas/química , Amidas/metabolismo , Amidas/farmacologia , Cristalografia por Raios X , Compostos Heterocíclicos/química , Compostos Heterocíclicos/metabolismo , Compostos Heterocíclicos/farmacologia , Humanos , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Oxalatos/metabolismo , Oxalatos/farmacologia , Piperidinas/metabolismo , Piperidinas/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologiaRESUMO
A novel series of N-pyridyl amides as potent p38alpha kinase inhibitors is described. Based on the structural similarities between the initial hit and a well-known imidazole pyrimidine series of p38alpha inhibitors, potencies within the newly discovered series were quickly improved by installation of an (S)-alpha-methylbenzyl moiety at the 2-position of the pyridine ring. The proposed binding modes of the new series to p38alpha were evaluated against SAR findings and provided rationale for further development of this series of molecules.
Assuntos
Amidas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Amidas/química , Descoberta de Drogas , Modelos Moleculares , Inibidores de Proteínas Quinases/química , Relação Estrutura-AtividadeRESUMO
Optimization of a tri-substituted N-pyridyl amide led to the discovery of a new class of potent N-pyrimidyl amide based p38alpha MAP kinase inhibitors. Initial SAR studies led to the identification of 5-dihydrofuran as an optimal hydrophobic group. Additional side chain modifications resulted in the introduction of hydrogen bond interactions. Through extensive SAR studies, analogs bearing free amino groups and alternatives to the parent (S)-alpha-methyl benzyl moiety were identified. These compounds exhibited improved cellular activities and maintained balance between p38alpha and CYP3A4 inhibition.
Assuntos
Amidas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/química , Amidas/química , Desenho de Fármacos , Modelos Moleculares , Inibidores de Proteínas Quinases/química , Relação Estrutura-AtividadeRESUMO
Derivatives of the 4-fluorobenzyl dimethylpiperazine-indole class of p38alpha MAP kinase inhibitors are described. Biological evaluation of these compounds focused on maintaining activity while improving pharmacokinetic (PK) properties. Improved properties were observed for structures bearing substitutions on the benzylic methylene.
Assuntos
Desenho de Fármacos , Indóis/síntese química , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Piperazinas/síntese química , Inibidores de Proteínas Quinases/síntese química , Animais , Cães , Haplorrinos , Humanos , Indóis/farmacocinética , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Piperazina , Piperazinas/farmacocinética , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Inibidores de Proteínas Quinases/farmacocinética , Estrutura Secundária de Proteína , RatosRESUMO
Herein, we report the identification and preclinical profile of a lead compound 10, (SPR519) as an equally potent dual inhibitor of PI3Kα and mTOR kinases. SPR519 exhibits an EC50 of low sub-micromolar range among various tested cancer cell lines such as A2780 (0.23 µM), PC3 (0.48 µM), and SKOV3 (0.50 µM). When administrated orally, it shows a considerably high plasma exposure (area under curve: 26,858 nM/h at 1 mg/kg) in mice. Moreover, it is found to be safe in animals with a dose of 30 mg/kg BID for 12 days in the dose tolerance study. SPR519 did not show any CYP or hERG liability. The identified lead compound demonstrates significant efficacy and bioavailability in ovarian and colon cancer xenograft models when evaluated for dose-ranging efficacy studies, at a dose as low as 2.5 mg/kg.
Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Neoplasias/tratamento farmacológico , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Administração Oral , Animais , Antineoplásicos/uso terapêutico , Disponibilidade Biológica , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Neoplasias/patologia , Inibidores de Proteínas Quinases/uso terapêuticoRESUMO
SPR965 is an inhibitor of PI3K and mTOR C1/C2 and has demonstrated anti-tumorigenic activity in a variety of solid tumors. We sought to determine the effects of SPR965 on cell proliferation and tumor growth in human serous ovarian cancer cell lines and a transgenic mouse model of high grade serous ovarian cancer (KpB model) and identify the underlying mechanisms by which SPR965 inhibits cell and tumor growth. SPR965 showed marked anti-proliferative activity by causing cell cycle arrest and inducing cellular stress in ovarian cancer cells. Treatment with SPR965 significantly inhibited tumor growth in KpB mice, accompanied by downregulation of Ki67 and VEGF and upregulation of Bip expression in ovarian tumors. SPR965 also inhibited adhesion and invasion through induction of the epithelial-mesenchymal transition process. As expected, downregulation of phosphorylation of AKT and S6 was observed in SPR965-treated ovarian cancer cells and tumors. Our results suggest that SPR965 has significant anti-tumorigenic effects in serous ovarian cancer in vitro and in vivo. Thus, SPR965 should be evaluated as a promising targeted agent in future clinical trials of ovarian cancer.
RESUMO
Paclitaxel is one of the most effective and widely used agents in treating a variety of cancers, including endometrial cancer. Because of its poor solubility in water, the current intravenous pharmaceutical paclitaxel is formulated in Cremophor EL and dehydrated in ethanol in equal volumes. Cremophor EL is capable of causing complement activation, which can trigger an immediate hypersensitivity reaction. SPR064 is a pro-drug of paclitaxel which has a much higher solubility as compared to the parent drug; hence, SPR064 can be conveniently formulated in non-cremapor based medium, reducing the risk of cremaphor-related hypersensitivity reactions. The pharmacokinetics and solubility of SPR064 were evaluated in rats. The anti-tumorigenic potential of SPR064 was compared to paclitaxel in endometrial cancer cell lines and a genetically engineered mouse model (Lkbfl/flp53fl/fl ) of endometrial cancer. Overall, SPR064 exhibited improved solubility and better exposure to drug in rats when compared to paclitaxel. SPR064 and paclitaxel inhibited cell proliferation, induced apoptosis, enhanced cellular stress and caused cell cycle G1 arrest in endometrial cancer cell lines, with similar potency. Both SPR064 and paclitaxel reduced tumor weight in the Lkbfl/flp53fl/fl mouse model under obese and lean conditions compared to their respective controls. Immunohistochemical staining demonstrated that SPR064 and paclitaxel significantly reduced the expression of Ki-67 and BCL-xL in the endometrial tumors of both obese and lean mice. In summary, SPR064 has anti-tumorigenic effects that are equivalent to paclitaxel in endometrial cancer cell lines and a genetically engineered mouse model of endometrial cancer. Thus, SPR064 may be a promising therapy for endometrial cancer without the significant risk of hypersensitivity reactions seen with paclitaxel.
RESUMO
Chronic obstructive pulmonary disease (COPD) is characterized by pulmonary inflammation, which is relatively insensitive to inhaled corticosteroids. The extent of the pulmonary inflammation in COPD correlates with disease severity, and it is thought to play a significant role in disease progression. We have evaluated a selective p38alpha-selective mitogen-activated protein kinase (MAPK) inhibitor, indole-5-carboxamide (ATP-competitive inhibitor of p38 kinase) (SD-282), in an 11-day model of tobacco smoke (TS)-induced pulmonary inflammation in A/J mice, by using dexamethasone as a reference steroid. Two oral treatment paradigms were evaluated in this TS model: prophylactic with daily pretreatment before each daily exposure, and therapeutic with daily treatment for 6 days commencing after 5 days of smoke exposure. Bronchoalveolar lavage and histological evaluation of lung sections taken after exposure to TS revealed an inflammatory response composed of increased numbers of macrophages and neutrophils and enhanced mucin staining. Phospho-p38 staining in macrophages and type II epithelial cells after TS exposure was also observed. Given prophylactically or therapeutically, dexamethasone failed to inhibit any of the TS-induced inflammatory changes. By contrast, SD-282 inhibited TS-induced increases in macrophages and neutrophils. Furthermore, SD 282 reduced TS-induced increases in cyclooxygenase-2 and interleukin-6 levels, and phospho-p38 expression in the lungs. In conclusion, SD-282 markedly reduced TS-induced inflammatory responses when given prophylactically or therapeutically whereas dexamethasone was ineffective. This is the first evidence that a p38alpha-selective MAPK inhibitor can exert pulmonary anti-inflammatory activity in a TS exposure model when given in a therapeutic mode, establishing the potential of p38 MAPK inhibitors as a therapy for COPD.
Assuntos
Modelos Animais de Doenças , Indóis/uso terapêutico , Pneumonia/enzimologia , Fumar/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Animais , Feminino , Indóis/farmacologia , Camundongos , Pneumonia/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/enzimologia , Fumaça/efeitos adversos , Fumar/tratamento farmacológico , Nicotiana/efeitos adversos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
A family of aryl-substituted maleimides was prepared and studied for their activity against calmodulin dependant kinase. Inhibitory activities against the enzyme ranged from 34nM to >20microM and were dependant upon both the nature of the aryl group and the hydrogen bond donating potential of the maleimide ring. Key interactions with the kinase ATP site and hinge region were found to be consistent with homology modeling predictions.
Assuntos
Derivados de Benzeno/farmacologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Maleimidas/farmacologia , Trifosfato de Adenosina/metabolismo , Derivados de Benzeno/síntese química , Sítios de Ligação , Inibidores Enzimáticos/síntese química , Indóis/síntese química , Maleimidas/síntese química , Modelos Químicos , Relação Estrutura-Atividade , Especificidade por SubstratoRESUMO
A family of aryl-substituted maleimides was prepared and studied for their activity against calmodulin-dependant kinase. Inhibitory activities against the enzyme ranged from 34nM to >20microM and were dependant upon both the nature of the aryl group and the tether joining the basic amine to the indolyl maleimide core. Key interactions with the kinase ATP site and hinge region, predicted by homology modeling, were confirmed.
Assuntos
Aminas/farmacologia , Derivados de Benzeno/farmacologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Maleimidas/farmacologia , Trifosfato de Adenosina/metabolismo , Aminas/química , Derivados de Benzeno/síntese química , Sítios de Ligação , Inibidores Enzimáticos/síntese química , Indóis/síntese química , Maleimidas/síntese química , Modelos Químicos , Relação Estrutura-Atividade , Especificidade por SubstratoRESUMO
A family of aryl-substituted maleimides was prepared and studied for their activity against calmodulin dependant kinase. Inhibitory activities against the enzyme ranged from 10nM to >20microM and were dependant upon both the nature of the aryl group and the tether joining the basic amine to the indolyl maleimide core of the inhibitors. Key interactions with the kinase ATP site and hinge region, predicted by homology modeling, were confirmed.
Assuntos
Derivados de Benzeno/farmacologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Maleimidas/farmacologia , Trifosfato de Adenosina/metabolismo , Derivados de Benzeno/síntese química , Sítios de Ligação , Inibidores Enzimáticos/síntese química , Interações Hidrofóbicas e Hidrofílicas , Indóis/síntese química , Maleimidas/síntese química , Modelos Químicos , Relação Estrutura-Atividade , Especificidade por SubstratoRESUMO
Non-ATP competitive pyrimidine-based inhibitors of CaMKIIdelta were identified. Computational studies were enlisted to predict the probable mode of binding. The results of the computational studies led to the design of ATP competitive inhibitors with optimized hinge interactions. Inhibitors of this class possessed improved enzyme and cellular activity compared to early leads.
Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Pirimidinas/farmacologia , Trifosfato de Adenosina/metabolismo , Ligação Competitiva , Inibidores Enzimáticos/síntese química , Modelos Químicos , Pirimidinas/química , Relação Estrutura-Atividade , Especificidade por SubstratoRESUMO
The focus of this work was to examine the potential role of p38 mitogen activated protein kinase (p38) in a mouse model of bone cancer (osteosarcoma) pain. To generate osteosarcoma and sham animals, osteosarcoma cells or medium were injected into the medullary canal of the femur. Initially, ipsilateral tactile allodynia was observed in both groups, but by 12 days post-surgery, thresholds in the sham group returned towards baseline while hypersensitivity in the osteosarcoma group lasted throughout the study. An increase in phosphorylated p38 was detected by western blotting in dorsal root ganglia (DRG) and spinal cord day 14 after surgery. Immunohistochemistry showed that p38 was phosphorylated in DRG and spinal dorsal horn neurons at this time point. Two doses of a selective p38 inhibitor, SCIO-469, were administered in the chow starting 5 days post-surgery and continued throughout the study. Treatment with SCIO-469 led to a decrease in osteosarcoma-induced clinical score but had no effect on the allodynia. Bone erosion and tumor growth were also examined but no significant reduction of bone erosion or tumor growth was observed in the SCIO-469 treated mice. These data suggest that the p38 signaling pathway does not play a major role in bone cancer-mediated pain.
Assuntos
Neoplasias Ósseas/complicações , Neoplasias Ósseas/enzimologia , Inibidores Enzimáticos/uso terapêutico , Indóis/uso terapêutico , Osteossarcoma/complicações , Osteossarcoma/enzimologia , Dor/enzimologia , Dor/etiologia , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Peso Corporal/fisiologia , Linhagem Celular Tumoral , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Ativação Enzimática/fisiologia , Gânglios Espinais/enzimologia , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C3H , Transplante de Neoplasias , Dor/tratamento farmacológico , Medição da Dor/efeitos dos fármacos , Limiar Sensorial/efeitos dos fármacos , Tomografia Computadorizada por Raios X , Vocalização Animal/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidoresRESUMO
The effects of small-molecule p38 inhibitors in numerous models of different disease states have been published, including those of SD-282, an indole-5-carboxamide inhibitor. The aim of the present study was to evaluate the pharmacological activity of SD-282 on cytokine production in vitro as well as in 2 in vivo models of inflammation in order to illuminate the role of this particular inhibitor in diverse disease states. The results presented here provide further characterization of SD-282 and provide a context in which to interpret the activity of this p38 inhibitor in models of arthritis, pain, myocardial injury, sepsis and asthma; all of which have an inflammatory component. SD-282 represents a valuable tool to elucidate the role of p38 MAP kinase in multiple models of inflammation.