RESUMO
Discovery of 5-(1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)-4,5-dihydroisoxazole-3-carboxamides as a new class of malonyl-coenzyme A decarboxylase (MCD) inhibitors is described. tert-Butyl 3-(5-(1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)-4,5-dihydroisoxazole-3-carboxamido)butanoate (5, CBM-301940) exhibited excellent potency and in vivo PK/ADME properties. It is the most powerful stimulant of glucose oxidation reported to date in isolated working rat hearts. Compound 5 improved the cardiac efficiency and function in a rat heart global ischemia/reperfusion model, suggesting MCD inhibitors may be useful for the treatment of ischemic heart diseases.
Assuntos
Carboxiliases/antagonistas & inibidores , Cardiotônicos/síntese química , Isoxazóis/síntese química , Administração Oral , Animais , Disponibilidade Biológica , Cardiotônicos/farmacocinética , Cardiotônicos/farmacologia , Cristalografia por Raios X , Isoxazóis/farmacocinética , Isoxazóis/farmacologia , Conformação Molecular , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/fisiopatologia , Reperfusão Miocárdica , Ratos , Ratos Sprague-Dawley , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
The discovery and structure-activity relationship of first-generation small-molecule malonyl-CoA decarboxylase (MCD; CoA = coenzyme A) inhibitors are reported. We demonstrated that MCD inhibitors increased malonyl-CoA concentration in the isolated working rat hearts. Malonyl-CoA is a potent, endogenous, and allosteric inhibitor of carnitine palmitoyltransferase-I (CPT-I), a key enzyme for mitochondrial fatty acid oxidation. As a result of the increase in malonyl-CoA levels, fatty acid oxidation rates were decreased and the glucose oxidation rates were significantly increased. Demonstration of in vivo efficacy of methyl 5-(N-(4-(1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)phenyl)morpholine-4-carboxamido)pentanoate (6u) in a pig ischemia model indicated that MCD inhibitors may be useful for treating ischemic heart diseases.
Assuntos
Carboxiliases/antagonistas & inibidores , Morfolinas/síntese química , Compostos de Fenilureia/síntese química , Animais , Metabolismo Energético/efeitos dos fármacos , Ácidos Graxos/metabolismo , Glucose/metabolismo , Técnicas In Vitro , Masculino , Malonil Coenzima A/metabolismo , Morfolinas/química , Morfolinas/farmacologia , Isquemia Miocárdica/tratamento farmacológico , Miocárdio/enzimologia , Miocárdio/metabolismo , Oxirredução , Compostos de Fenilureia/química , Compostos de Fenilureia/farmacologia , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , SuínosRESUMO
Abnormally high rates of fatty acid oxidation and low rates of glucose oxidation are important contributors to the severity of ischemic heart disease. Malonyl coenzyme A (CoA) regulates fatty acid oxidation by inhibiting mitochondrial uptake of fatty acids. Malonyl CoA decarboxylase (MCD) is involved in the decarboxylation of malonyl CoA to acetyl CoA. Therefore, inhibition of MCD may decrease fatty acid oxidation and protect the ischemic heart, secondary to increasing malonyl CoA levels. Ex vivo working rat hearts aerobically perfused in the presence of newly developed MCD inhibitors showed an increase in malonyl CoA levels, which was accompanied by both a significant decrease in fatty acid oxidation rates and an increase in glucose oxidation rates compared with controls. Using a model of demand-induced ischemia in pigs, MCD inhibition significantly increased glucose oxidation rates and reduced lactate production compared with vehicle-treated hearts, which was accompanied by a significant increase in cardiac work compared with controls. In a more severe rat heart global ischemia/reperfusion model, glucose oxidation was significantly increased and cardiac function was significantly improved during reperfusion in hearts treated with the MCD inhibitor compared with controls. Together, our data show that MCD inhibitors, which increase myocardial malonyl CoA levels, decrease fatty acid oxidation and accelerate glucose oxidation in both ex vivo rat hearts and in vivo pig hearts. This switch in energy substrate preference improves cardiac function during and after ischemia, suggesting that pharmacological inhibition of MCD may be a novel approach to treating ischemic heart disease.
Assuntos
Carboxiliases/antagonistas & inibidores , Cardiotônicos/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Ácidos Graxos/metabolismo , Glucose/metabolismo , Isquemia Miocárdica/tratamento farmacológico , Miocárdio/metabolismo , Acetilcoenzima A , Animais , Cardiotônicos/farmacologia , Metabolismo Energético , Inibidores Enzimáticos/farmacologia , Ésteres/metabolismo , Glicólise , Malonil Coenzima A/metabolismo , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Modelos Animais , Isquemia Miocárdica/metabolismo , Oxirredução , Ratos , Ratos Sprague-Dawley , SuínosRESUMO
The syntheses of two labeled homologues of (2E,4E,6E)-7-(3,5-di-tert-butylphenyl)-3-methylocta-2,4,6-trienoic acid (ALRT1550, 2), [(13)CD(3)]ALRT1550 (3) and [(3)H]ALRT1550 (4), are described in this report. ALRT1550 is an exceptionally potent antiproliferative agent which is currently in phase I/II clinical trials for acute chemotherapy. Both homologues were prepared from commercially available 3,5-di-tert-butylbenzoic acid. Homologue [(13)CD(3)]ALRT1550 was labeled at the 7-position of the trienoic acid chain via addition of [(13)CD(3)]MgI to a Weinreb amide precursor. The preparation of [(3)H]ALRT1550 utilized novel methodology to synthesize a sterically hindered and site-specific tritium-labeled tert-butyl group. Saturation binding and Scatchard analysis of this ligand at the retinoic acid receptors are also described, along with competition binding (K(i)) values for a series of known retinoids using [(3)H]ALRT1550 or [(3)H]ATRA as the labeled probes.
RESUMO
A series of trifluoroacetophenone derivatives were prepared and evaluated as malonyl-CoA decarboxylase (MCD) inhibitors. Some of the 'reverse amide' analogs were found to be potent inhibitors of MCD enzyme activity. The trifluoroacetyl group may interact with the MCD active site as the hydrate in a similar fashion to the hexafluoroisopropanol analogs reported previously. Adding electron-withdrawing groups to the phenyl ring stabilizes the hydrated species and enhances this interaction.
Assuntos
Acetofenonas/síntese química , Acetofenonas/farmacologia , Carboxiliases/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Indicadores e Reagentes , Malonil Coenzima A/metabolismo , Propanóis/química , Relação Estrutura-AtividadeRESUMO
We have previously reported the discovery of small molecule inhibitors of malonyl-CoA decarboxylase (MCD) as novel metabolic modulators, which inhibited fatty acid oxidation and consequently increased the glucose oxidation rates in the isolated working rat hearts. MCD inhibitors were also shown to improve cardiac efficiency in rat and pig demand-induced ischemic models through the mechanism-based modulation of energy metabolism. Herein, we describe the design and synthesis of a series of novel heterocyclic MCD inhibitors with a preference for substituted imidazole and isoxazole.
Assuntos
Carboxiliases/antagonistas & inibidores , Cardiotônicos/síntese química , Inibidores Enzimáticos/síntese química , Animais , Cardiotônicos/farmacologia , Desenho de Fármacos , Metabolismo Energético , Inibidores Enzimáticos/farmacologia , Ácidos Graxos/metabolismo , Glucose/metabolismo , Imidazóis/química , Modelos Químicos , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/metabolismo , Oxirredução , Ratos , SuínosRESUMO
A new structurally simple series of potent lipophilic aza-retinoids RXR agonists has been developed. SAR studies for the N-alkyl-azadienoic acids described here demonstrate that the RXR activity profile is sensitive to the N-alkyl chain length. Further, we have expanded the work to include azadienoic acids, which exhibited many accessible conformations leading to a better understanding of the SAR around the series.
Assuntos
Compostos Aza/farmacologia , Receptores X de Retinoides/agonistas , Retinoides/farmacologia , Compostos Aza/síntese química , Compostos Aza/química , Estrutura Molecular , Retinoides/síntese química , Retinoides/química , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
A series of heteroaryl-substituted bis-trifluoromethyl carbinols were prepared and evaluated as malonyl-CoA decarboxylase (MCD) inhibitors. Some thiazole-based derivatives showed potent in vitro MCD inhibitory activities and significantly increased glucose oxidation rates in isolated working rat hearts.
Assuntos
Carboxiliases/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Compostos Heterocíclicos/química , Metanol/síntese química , Metanol/farmacologia , Animais , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/química , Glucose/química , Glucose/metabolismo , Coração/efeitos dos fármacos , Técnicas In Vitro , Metanol/análogos & derivados , Estrutura Molecular , Oxirredução , Ratos , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
A series of novel cyclopropanyl methyl hexadienoic acid retinoids was designed and prepared. These compounds exhibited either selective activity as RXR agonists or pan-agonists on one or more of each of the RAR and RXR isoforms. The most potent pan-agonist 5a (RAR's EC(50)=17-59 nM; RXR's EC(50)=6-14 nM) showed good antiproliferative properties in the in vitro cancer cell lines, ME 180 and RPMI 8226.
Assuntos
Ciclopropanos/síntese química , Ciclopropanos/farmacologia , Receptores do Ácido Retinoico/efeitos dos fármacos , Ácido Sórbico/análogos & derivados , Ligação Competitiva/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Humanos , Indicadores e Reagentes , Ligantes , Receptores do Ácido Retinoico/agonistas , Receptores do Ácido Retinoico/genética , Ácido Sórbico/síntese química , Ácido Sórbico/farmacologia , Transfecção , Células Tumorais CultivadasRESUMO
The discovery and structure-activity relationship of a novel series of coumarin-based TNF-alpha inhibitors is described. Starting from the initial lead 1a, various derivatives were prepared surrounding the coumarin core structure to optimize the in vitro inhibitory activity of TNF-alpha production by human peripheral blood mononuclear cells (hPBMC), stimulated by bacterial lipopolysaccharide (LPS). Selected compounds also demonstrated in vivo inhibition of TNF-alpha production in rats.
Assuntos
Cumarínicos/síntese química , Cumarínicos/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Concentração Inibidora 50 , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/farmacologia , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/metabolismoRESUMO
The recombinant human malonyl-CoA decarboxylase (hMCD) was overexpressed in Escherichia coli with and without the first 39 N-terminal amino acids via a cleavable MBP-fusion construct. Proteolytic digestion using genenase I to remove the MBP-fusion tag was optimized for both the full length and truncated hMCD. The apo-hMCD enzymes were solubilized and purified to homogeneity. Steady-state kinetic characterization showed similar kinetic parameters for the MBP-fused and apo-hMCD enzymes with an apparent Km value of approximately 330-520 microM and a turnover rate kcat of 13-28s(-1). For the apo-hMCD enzymes, the N-terminal truncated hMCD was well tolerated over a broad pH range (pH 4-10); whereas the full-length hMCD appeared to be stable only at pH >/= 8.5. Our results showed that the N-terminal region of hMCD has no effect on the catalytic activity of the enzyme but plays a role in the folding process and conformation stability of hMCD.