RESUMEN
Five new meroterpenes, 12α-Psoracorylifol F (1), 7ß,8α-hydroxy-12ß-Psoracorylifol F (2), 8-ketone-Cyclobakuchiol C (3), 7α,8ß-hydroxy-12ß-Cyclobakuchiol C (4) and 8α-hydroxy-Cyclobakuchiol C (5) together with six known compounds (6-11) were isolated from seeds of Psoralea corylifolia, and their structures were elucidated on the basis of spectroscopic and physicochemical analyses. All the isolates were evaluated for in vitro inhibitory activity against DGAT1/2. Among them, compounds 1-6 were found to exhibit selective inhibitory activity on DGAT1 with IC50 values ranging from 61.5 ± 1.1 to 89.1 ± 1.2 µM.
Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Psoralea/química , Terpenos/farmacología , Animales , China , Células HEK293 , Humanos , Estructura Molecular , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Semillas/química , Células Sf9 , Relación Estructura-Actividad , Terpenos/aislamiento & purificaciónRESUMEN
A new aurone named (2Z)-2-[(4'-hydroxyphenyl) methylene]-6-hydroxy-7-prenyl-3(2H)-benzofurane (1), two new flavonoids named (2S)-7-methoxy-6-(2-hydroxy-3-methylbut-3-en-1-yl)-2-(4-hydroxyphenyl)chroman-4-one (2), (2S)-4'-hydroxyl-7-hydroxymethylene-6-(2â³,3â³-epoxy-3â³-methylbutyl)flavanone (3), and a new coumestan named bavacoumestan E (4), together with eleven known compounds (5-15), were isolated from the seeds of Psoralea corylifolia. The chemical structures were elucidated by spectroscopic and physico-chemical analyses. All isolates were evaluated for in vitro inhibitory activity against DGAT, PTP1B and α-glucosidase. Compounds 1, 2 and 3 showed potential inhibitory activities on DGAT1 with IC50 values of 35.2⯱â¯1.3, 51.3⯱â¯1.1 and 43.4⯱â¯0.7⯵M, respectively. Compounds 6 and 8 displayed the significant inhibitory activities on α-glucosidase with IC50 value of 28.0 and 23.0⯵M, respectively.
Asunto(s)
Flavonoides/farmacología , Hipoglucemiantes/farmacología , Psoralea/química , Semillas/química , China , Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Flavonoides/aislamiento & purificación , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Inhibidores de Glicósido Hidrolasas/farmacología , Células HEK293 , Humanos , Hipoglucemiantes/aislamiento & purificación , Estructura Molecular , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidoresRESUMEN
A new bakuchiol compound Δ11-12-hydroxy-12-dimethyl bakuchiol (1), a new flavanone compound 2(S)-6-methoxy-7- hydroxymethylene-4'-hydroxyl-flavanone (8), and two new isoflavanone compounds 4',7-dihydroxy-3'-(6"ß-hydroxy-3â³,7â³-dimethyl-,2â³,7â³-dibutenyl)-geranylisoflavone (9) and 4',7-dihydroxy-3'-(7â³-hydroxy-7â³-methyl-2â³,5â³-dibutenyl)-geranylisoflavone (10) together with eight known compounds (2-7, 11, 12) were isolated from the P. corylifolia. Their structures were elucidated on the basis of spectroscopic and physico-chemical analyses. All the isolates were evaluated for in vitro inhibitory activity against DGAT1/2. Among them, compounds 3, 9 and 10 were found to exhibit selective inhibitory activity on DGAT1 with IC50 values ranging from 93.7⯱â¯1.3 to 96.2⯱â¯1.1⯵M. Compound 1 showed inhibition activity on DGAT1 with IC50 values 73.4⯱â¯1.3⯵M and inhibition of DGAT2 with IC50 value 121.1⯱â¯1.3⯵M.
Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Isoflavonas/aislamiento & purificación , Fenoles/aislamiento & purificación , Psoralea/química , Estructura Molecular , Semillas/químicaRESUMEN
Diacylglycerol acyltransferase (DGAT) is expressed abundantly in intestine, liver, and adipose tissues. DGAT1 is the crucial and rate-limiting enzyme that mediates the final step in triacylglycerol (TAG) resynthesis during dietary fat absorption. However, too much triacylglycerol (TAG) reserve will lead to genetic obesity (Hubert et al., 2000). DGAT1 knockout mice could survive and displayed a reduction in the postprandial rise of plasma TG, and increased sensitivity of insulin and leptin. Here we report the discovery and characterization of a novel selective DGAT1 inhibitor 29 to potentially treat obesity. Compound 29 showed lipid lowering effect in mouse lipid tolerance test (LTT) and also reduced body weight in DIO mice without observable liver damage.
Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Grasas de la Dieta/efectos adversos , Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Ácidos Grasos Insaturados/farmacología , Obesidad/tratamiento farmacológico , Administración Oral , Aminoácidos Aromáticos , Animales , Disponibilidad Biológica , Peso Corporal/efectos de los fármacos , Diacilglicerol O-Acetiltransferasa/deficiencia , Diacilglicerol O-Acetiltransferasa/metabolismo , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Ácidos Grasos Insaturados/administración & dosificación , Ácidos Grasos Insaturados/química , Células HEK293 , Humanos , Ratones , Ratones Noqueados , Estructura Molecular , Obesidad/metabolismo , Relación Estructura-ActividadRESUMEN
Whereas atherogenicity of dietary lipids has been largely studied, relatively little is known about the possible contribution of dietary amino acids to macrophage foam-cell formation, a hallmark of early atherogenesis. Recently, we showed that leucine has antiatherogenic properties in the macrophage model system. In this study, an in-depth investigation of the role of leucine in macrophage lipid metabolism was conducted by supplementing humans, mice, or cultured macrophages with leucine. Macrophage incubation with serum obtained from healthy adults supplemented with leucine (5 g/d, 3 weeks) significantly decreased cellular cholesterol mass by inhibiting the rate of cholesterol biosynthesis and increasing cholesterol efflux from macrophages. Similarly, leucine supplementation to C57BL/6 mice (8 weeks) resulted in decreased cholesterol content in their harvested peritoneal macrophages (MPM) in relation with reduced cholesterol biosynthesis rate. Studies in J774A.1 murine macrophages revealed that leucine dose-dependently decreased cellular cholesterol and triglyceride mass. Macrophages treated with leucine (0.2 mM) showed attenuated uptake of very low-density lipoproteins and triglyceride biosynthesis rate, with a concurrent down-regulation of diacylglycerol acyltransferase-1, a key enzyme catalyzing triglyceride biosynthesis in macrophages. Similar effects were observed when macrophages were treated with α-ketoisocaproate, a key leucine metabolite. Finally, both in vivo and in vitro leucine supplementation significantly improved macrophage mitochondrial respiration and ATP production. The above studies, conducted in human, mice, and cultured macrophages, highlight a protective role for leucine attenuating macrophage foam-cell formation by mechanisms related to the metabolism of cholesterol, triglycerides, and energy production. © 2018 BioFactors, 44(3):245-262, 2018.
Asunto(s)
Anticolesterolemiantes/farmacología , Suplementos Dietéticos , Células Espumosas/efectos de los fármacos , Cetoácidos/farmacología , Leucina/farmacología , Macrófagos/efectos de los fármacos , Adenosina Trifosfato/agonistas , Adenosina Trifosfato/biosíntesis , Adolescente , Adulto , Animales , Diferenciación Celular/efectos de los fármacos , Línea Celular , Colesterol/biosíntesis , VLDL-Colesterol/antagonistas & inhibidores , VLDL-Colesterol/biosíntesis , Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Diacilglicerol O-Acetiltransferasa/metabolismo , Relación Dosis-Respuesta a Droga , Células Espumosas/citología , Células Espumosas/metabolismo , Voluntarios Sanos , Humanos , Macrófagos/citología , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Fosforilación Oxidativa/efectos de los fármacos , Triglicéridos/antagonistas & inhibidores , Triglicéridos/biosíntesisRESUMEN
A series of diacylglycerol O-acyltransferase 1 (DGAT-1) inhibitors with a picolinoylpyrrolidine-2-carboxylic acid moiety were designed and synthesized. Of these compounds, compound 22 exhibited excellent DGAT-1-inhibitory activity (hDGAT-1 enzyme assay, 50% inhibitory concentration [IC50]=3.5±0.9nM) and effectively reduced the intracellular triglyceride contents in 3T3-L1, HepG2 and Caco-2 cells. A preliminary study of the plasma and tissue distributions of compound 22 in mice revealed low plasma exposure and high concentrations in different segments of the intestine and liver, which may facilitate targeting DGAT-1. Furthermore, in an acute lipid challenge test, compound 22 showed a dose-dependent inhibitory effect on high-serum triglycerides in C57/KSJ mice induced by olive oil (1, 3, and 10mg/kg, i.g.).
Asunto(s)
Ácidos Carboxílicos/química , Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Inhibidores Enzimáticos/química , Animales , Células CACO-2 , Ácidos Carboxílicos/síntesis química , Ácidos Carboxílicos/farmacología , Diacilglicerol O-Acetiltransferasa/metabolismo , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacocinética , Semivida , Células Hep G2 , Humanos , Concentración 50 Inhibidora , Masculino , Ratones , Ratones Endogámicos C57BL , Permeabilidad/efectos de los fármacos , Pirrolidinas/química , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad , Distribución Tisular , Triglicéridos/sangreRESUMEN
Hypertriglyceridemia (triglycerides > 150 mg/dL) affects ~25 % of the United States (US) population and is associated with increased cardiovascular risk. Severe hypertriglyceridemia (≥ 500 mg/dL) is also a risk factor for pancreatitis. Three omega-3 fatty acid (OM3FA) prescription formulations are approved in the US for the treatment of adults with severe hypertriglyceridemia: (1) OM3FA ethyl esters (OM3EE), a mixture of OM3FA ethyl esters, primarily eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (Lovaza®, Omtryg™, and generics); (2) icosapent ethyl (IPE), EPA ethyl esters (Vascepa®); and (3) omega-3 carboxylic acids (OM3CA), a mixture of OM3FAs in free fatty acid form, primarily EPA, DHA, and docosapentaenoic acid (Epanova®). At approved doses, all formulations substantially reduce triglyceride and very-low-density lipoprotein levels. DHA-containing formulations may also increase low-density lipoprotein cholesterol. However, this is not accompanied by increased non-high-density lipoprotein cholesterol, which is thought to provide a better indication of cardiovascular risk in this patient population. Proposed mechanisms of action of OM3FAs include inhibition of diacylglycerol acyltransferase, increased plasma lipoprotein lipase activity, decreased hepatic lipogenesis, and increased hepatic ß-oxidation. OM3CA bioavailability (area under the plasma concentration-time curve from zero to the last measurable concentration) is up to 4-fold greater than that of OM3FA ethyl esters, and unlike ethyl esters, the absorption of OM3CA is not dependent on pancreatic lipase hydrolysis. All three formulations are well tolerated (the most common adverse events are gastrointestinal) and demonstrate a lack of drug-drug interactions with other lipid-lowering drugs, such as statins and fibrates. OM3FAs appear to be an effective treatment option for patients with severe hypertriglyceridemia.
Asunto(s)
Ácidos Docosahexaenoicos/uso terapéutico , Ácido Eicosapentaenoico/análogos & derivados , Ácidos Grasos Omega-3/uso terapéutico , Hipertrigliceridemia/tratamiento farmacológico , Hipolipemiantes/uso terapéutico , Triglicéridos/antagonistas & inhibidores , Adulto , Disponibilidad Biológica , LDL-Colesterol/sangre , Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Diacilglicerol O-Acetiltransferasa/metabolismo , Ácidos Docosahexaenoicos/farmacocinética , Combinación de Medicamentos , Ácido Eicosapentaenoico/farmacocinética , Ácido Eicosapentaenoico/uso terapéutico , Ésteres , Ácidos Grasos Omega-3/farmacocinética , Humanos , Hipertrigliceridemia/sangre , Hipertrigliceridemia/patología , Hipolipemiantes/farmacocinética , Lipogénesis/efectos de los fármacos , Lipoproteína Lipasa/metabolismo , Lipoproteínas VLDL/antagonistas & inhibidores , Lipoproteínas VLDL/sangre , Hígado/efectos de los fármacos , Hígado/metabolismo , Oxidación-Reducción/efectos de los fármacos , Triglicéridos/sangreRESUMEN
Four new sesqui-lignans, (7R, 7'R, 7â³S, 8S, 8'S, 8â³S)-4',5â³-dihydroxy-3,5,3',4â³-tetramethoxy-7,9':7',9-diepoxy-4,8â³-oxy-8,8'-sesquineo-lignan-7â³,9â³-diol (1), (7R, 7'R, 7â³S, 8S, 8'S, 8â³S)-4',3â³-dihydroxy-3,5,3',5',4â³-pentamethoxy-7,9':7',9-diepoxy-4,8â³-oxy-8,8'-sesquineo-lignan-7â³,9â³-diol (2), (7R, 7'R, 7â³S, 8S, 8'S, 8â³S)-3',4â³-dihydroxy-3,5,4',5â³-tetramethoxy-7,9':7',9-diepoxy-4,8â³-oxy-8,8'-sesquineo-lignan-7â³,9â³-diol (3) and acanthopanax A (7) together with three known compounds (4-6) were isolated from the EtOAc-soluble extract of Acanthopanax senticosus. Their structures were elucidated on the basis of spectroscopic and physicochemical analyses. All the isolates were evaluated for in vitro inhibitory activity against DGAT1 and DGAT2. Among them, compounds 1-6 were found to exhibit selective inhibitory activity on DGAT1 with IC50 values ranging from 61.1 ± 1.3 to 97.7 ± 1.1 µM and compound 7 showed selective inhibition of DGAT2 with IC50 value 93.2 ± 1.2.
Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Eleutherococcus/química , Lignanos/química , Lignanos/aislamiento & purificación , Estructura Molecular , Tallos de la Planta/químicaRESUMEN
OBJECTIVE: Chinese crude drug Mori Cortex Radicis (the root cortex of Morus species) has been used as a folk medicine to treat hypertension, diabetes, as well as in expectorant, diuretic agents. This investigation aims to study the anti-hyperlipidemia effects of Mori Cortex Radicis (MCR) extracts in hyperlipidemic rat models and the potential therapeutic activities of compounds isolated from the extracts. MATERIALS AND METHODS: The effects of MCR on hypolipidemic parameters were investigated using Wistar rats induced by high-lipid emulsion. Sixty healthy Wistar rats were randomly divided into 6 groups: normal group, hyperlipidaemia model group, simvastatin, and high-, medium- and low-dose MCR extracts. After four weeks, body weight, total cholesterol (TC), triglycerides (TG), high and low-density lipoproteins (HDL, LDL), as well as aspartate aminotransferase (AST), alanine aminotransferase (ALT) were measured. To further investigation, four major active compounds were isolated from extracts through high performance liquid chromatography (HPLC) and their diacylglycerol acyltransferase 1 (DGAT1) inhibitory activity was evaluated. RESULTS: MCR dose-dependently reduced serum TC, TG, LDL-C, inhibited the activity of ALT, AST, and increased HDL-C. Furthermore, in vitro biochemistry tests revealed that four active isolates showed moderate inhibitory activity against DGAT1 with IC50 values ranging from 62.1 ± 1.2 to 99.3 ± 2.3 µM. CONCLUSIONS: The results demonstrated that MCR could effectively ameliorate hyperlipidaemia and inhibit DGAT1 that a key enzyme closely related to hyperlipidaemia and type 2 diabetes. It may provide a new pharmacological basis for treating hyperlipidaemia and related diseases using MCR.
Asunto(s)
Hiperlipidemias/sangre , Hipolipemiantes/farmacología , Morus , Extractos Vegetales/farmacología , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Diacilglicerol O-Acetiltransferasa/metabolismo , Hiperlipidemias/tratamiento farmacológico , Hipolipemiantes/uso terapéutico , Lípidos/sangre , Masculino , Microsomas Hepáticos/metabolismo , Fitoterapia , Corteza de la Planta , Extractos Vegetales/uso terapéutico , Raíces de Plantas , Ratas Sprague-Dawley , Ratas WistarRESUMEN
Diamide compounds were identified as potent DGAT1 inhibitors in vitro, but their poor molecular properties resulted in low oral bioavailability, both systemically and to DGAT1 in the enterocytes of the small intestine, resulting in a lack of efficacy in vivo. Replacing an N-alkyl group on the diamide with an N-aryl group was found to be an effective strategy to confer oral bioavailability and oral efficacy in this lipophilic diamide class of inhibitors.
Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Diamida/química , Inhibidores Enzimáticos/química , Animales , Línea Celular Tumoral , Diacilglicerol O-Acetiltransferasa/metabolismo , Diamida/síntesis química , Diamida/farmacocinética , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacocinética , Semivida , Humanos , Ratas , Ratas Sprague-Dawley , Relación Estructura-ActividadRESUMEN
Parenteral nutrition (PN) has been strongly associated with intestinal failure-associated liver disease. Cholestasis, liver steatosis, and liver fibrosis are features of this liver injury, which can progress to end stage liver disease. Omega-3 fatty acid rich PN has been shown to alleviate cholestasis and steatosis. There have been reports although suggesting that it may not be able to arrest or reverse the progression to liver fibrosis. In this article, we develop a hypothesis of the mechanism of how Ω-3 fatty acid rich PN may influence the progression of fibrosis.
Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Emulsiones Grasas Intravenosas/efectos adversos , Ácidos Grasos Omega-3/efectos adversos , Cirrosis Hepática/etiología , Modelos Biológicos , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Nutrición Parenteral/efectos adversos , Animales , Colestasis Intrahepática/etiología , Colestasis Intrahepática/metabolismo , Colestasis Intrahepática/prevención & control , Diacilglicerol O-Acetiltransferasa/metabolismo , Emulsiones Grasas Intravenosas/metabolismo , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-3/metabolismo , Humanos , Hígado/enzimología , Hígado/metabolismo , Cirrosis Hepática/enzimología , Cirrosis Hepática/metabolismo , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Triglicéridos/metabolismoRESUMEN
Two new lignans were isolated from Saururus chinensis, along with eight known compounds. Their structures were elucidated on the basis of spectroscopic and physico-chemical analyses. All the isolates were evaluated for in vitro inhibitory activity against DGAT1 and DGAT2. Among them, compounds 2, 3, 5 and 7 were found to exhibit selective inhibitory activity on DGAT1 with IC50 values ranging from 44.3±1.5 to 87.5±1.3µM.
Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Inhibidores Enzimáticos/química , Lignanos/química , Saururaceae/química , Inhibidores Enzimáticos/aislamiento & purificación , Células HEK293 , Humanos , Concentración 50 Inhibidora , Lignanos/aislamiento & purificación , Estructura Molecular , Raíces de Plantas/químicaRESUMEN
A new prenylated flavanone, erythraddison Z (1), together with eight known flavonoids (2-9), was isolated from the stem bark of Maackia amurensis. Their structures were elucidated on the basis of spectroscopic methods, including 1D and 2D NMR (COSY, HMQC, and HMBC) techniques. All the isolates, with the exception of 3, 6 and 7, strongly inhibited diacylglycerol acyltransferase activity in an in vitro assay with IC50 values ranging from 96.5 ± 0.6 to 135.1 ± 1.4 µM.
Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Flavanonas/aislamiento & purificación , Flavanonas/farmacología , Maackia/química , Medicamentos Herbarios Chinos/química , Flavanonas/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Corteza de la Planta/química , PrenilaciónRESUMEN
Hydroxytyrosol, tyrosol, and oleuropein, the main phenols present in extra virgin olive oil, have been reported to exert several biochemical and pharmacological effects. Here, we investigated the short-term effects of these compounds on lipid synthesis in primary-cultured rat-liver cells. Hydroxytyrosol, tyrosol and oleuropein inhibited both de novo fatty acid and cholesterol syntheses without an effect on cell viability. The inhibitory effect of individual compounds was already evident within 2 h of 25 µM phenol addition to the hepatocytes. The degree of cholesterogenesis reduction was similar for all phenol treatments (-25/30%), while fatty acid synthesis showed the following order of inhibition: hydroxytyrosol (-49%) = oleuropein (-48%) > tyrosol (-30%). A phenol-induced reduction of triglyceride synthesis was also detected. To clarify the lipid-lowering mechanism of these compounds, their influence on the activity of key enzymes of fatty acid biosynthesis (acetyl-CoA carboxylase and fatty acid synthase), triglyceride synthesis (diacylglycerol acyltransferase) and cholesterogenesis (3-hydroxy-3-methyl-glutaryl-CoA reductase) was investigated in situ by using digitonin-permeabilized hepatocytes. Acetyl-CoA carboxylase, diacylglycerol acyltransferase and 3-hydroxy-3-methyl-glutaryl-CoA reductase activities were reduced after 2 h of 25 µM phenol treatment. No change in fatty acid synthase activity was observed. Acetyl-CoA carboxylase inhibition (hydroxytyrosol, -41%, = oleuropein, -38%, > tyrosol, -17%) appears to be mediated by phosphorylation of AMP-activated protein kinase. These findings suggest that a decrease in hepatic lipid synthesis may represent a potential mechanism underlying the reported hypolipidemic effect of phenols of extra virgin olive oil.
Asunto(s)
Ácidos Grasos/biosíntesis , Hepatocitos/metabolismo , Lípidos/biosíntesis , Lipogénesis/efectos de los fármacos , Aceites de Plantas/farmacología , Proteínas Quinasas Activadas por AMP/metabolismo , Acetil-CoA Carboxilasa/antagonistas & inhibidores , Animales , Células Cultivadas , Colesterol/biosíntesis , Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Regulación hacia Abajo , Hepatocitos/efectos de los fármacos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Glucósidos Iridoides , Iridoides/farmacología , Masculino , Aceite de Oliva , Alcohol Feniletílico/análogos & derivados , Alcohol Feniletílico/farmacología , Fosforilación , Ratas WistarRESUMEN
DGAT-1 is an enzyme that catalyzes the final step in triglyceride synthesis. mRNA knockout experiments in rodent models suggest that inhibitors of this enzyme could be of value in the treatment of obesity and type II diabetes. The carboxylic acid-based DGAT-1 inhibitor 1 was advanced to clinical trials for the treatment of type 2 diabetes, despite of the low passive permeability of 1. Because of questions relating to the potential attenuation of distribution and efficacy of a poorly permeable agent, efforts were initiated to identify compounds with improved permeability. Replacement of the acid moiety in 1 with an oxadiazole led to the discovery of 52, which possesses substantially improved passive permeability. The resulting pharmacodynamic profile of this neutral DGAT-1 inhibitor was found to be similar to 1 at comparable plasma exposures.
Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Inhibidores Enzimáticos/química , Oxazepinas/química , Administración Oral , Animales , Diacilglicerol O-Acetiltransferasa/metabolismo , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/uso terapéutico , Semivida , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , Obesidad/tratamiento farmacológico , Oxadiazoles/química , Oxazepinas/farmacocinética , Oxazepinas/uso terapéutico , Unión Proteica , Ratas , Relación Estructura-ActividadRESUMEN
Alterations in fat metabolism, in particular elevated plasma concentrations of free fatty acids and triglycerides (TG), have been implicated in the pathogenesis of Type 2 diabetes, obesity, and cardiovascular disease. Acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1), a member of the large family of membrane-bound O-acyltransferases, catalyzes the final step in triacylglycerol formation. In the intestine, DGAT1 is one of the acyltransferases responsible for the reesterficiation of dietary TG. Following a single dose of a selective pharmacological inhibitor of DGAT1, PF-04620110, a dose-dependent inhibition of TG and vitamin A absorption postprandially was demonstrated in rodents and human subjects. In C57/BL6J mice, acute DGAT1 inhibition alters the temporal and spatial pattern of dietary lipid absorption. To understand the impact of DGAT1 inhibition on enterocyte lipid metabolism, lipomic profiling was performed in rat intestine and plasma as well as human plasma. DGAT1 inhibition causes an enrichment of polyunsaturated fatty acids within the TG class of lipids. This pharmacological intervention gives us insight as to the role of DGAT1 in human dietary lipid absorption.
Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Absorción Intestinal/efectos de los fármacos , Oxazepinas/farmacología , Adolescente , Adulto , Animales , Estudios de Casos y Controles , Diacilglicerol O-Acetiltransferasa/genética , Diacilglicerol O-Acetiltransferasa/metabolismo , Grasas de la Dieta/sangre , Grasas de la Dieta/metabolismo , Relación Dosis-Respuesta a Droga , Enterocitos/metabolismo , Inhibidores Enzimáticos/farmacocinética , Ácidos Grasos Insaturados/sangre , Ácidos Grasos Insaturados/metabolismo , Femenino , Humanos , Mucosa Intestinal/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Oxazepinas/farmacocinética , Periodo Posprandial , Ratas , Ratas Sprague-Dawley , Triglicéridos/sangre , Triglicéridos/metabolismo , Vitamina A/metabolismoRESUMEN
A new series of pyrazinecarboxamide DGAT1 inhibitors was designed to address the need for a candidate drug with good potency, selectivity, and physical and DMPK properties combined with a low predicted dose in man. Rational design and optimization of this series led to the discovery of compound 30 (AZD7687), which met the project objectives for potency, selectivity, in particular over ACAT1, solubility, and preclinical PK profiles. This compound showed the anticipated excellent pharmacokinetic properties in human volunteers.
Asunto(s)
Acetatos/química , Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Inhibidores Enzimáticos/química , Pirazinas/química , Acetatos/farmacocinética , Acetatos/farmacología , Animales , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/farmacología , Humanos , Espectroscopía de Resonancia Magnética , Pirazinas/farmacocinética , Pirazinas/farmacología , Ratas , SolubilidadRESUMEN
A novel series of DGAT-1 inhibitors was discovered from an oxadiazole amide high throughput screening (HTS) hit. Optimisation of potency and ligand lipophilicity efficiency (LLE) resulted in a carboxylic acid containing clinical candidate 53 (AZD3988), which demonstrated excellent DGAT-1 potency (0.6 nM), good pharmacokinetics and pre-clinical in vivo efficacy that could be rationalised through a PK/PD relationship.
Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Inhibidores Enzimáticos/síntesis química , Hipoglucemiantes/síntesis química , Oxadiazoles/síntesis química , Animales , Diabetes Mellitus/tratamiento farmacológico , Diacilglicerol O-Acetiltransferasa/metabolismo , Perros , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/farmacología , Semivida , Ensayos Analíticos de Alto Rendimiento , Humanos , Hipoglucemiantes/farmacocinética , Hipoglucemiantes/farmacología , Ligandos , Ratones , Obesidad/tratamiento farmacológico , Oxadiazoles/farmacocinética , Relación Estructura-Actividad Cuantitativa , RatasRESUMEN
Acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1) is one of two known DGAT enzymes that catalyze the final step in triglyceride synthesis. Findings from genetically modified mice as well as pharmacological studies suggest that inhibition of DGAT1 is a promising strategy for the treatment of obesity and type 2 diabetes. Here we characterize a tool DGAT1 inhibitor compound, T863. We found that T863 is a potent inhibitor for both human and mouse DGAT1 in vitro, which acts on the acyl-CoA binding site of DGAT1 and inhibits DGAT1-mediated triacylglycerol formation in cells. In an acute lipid challenge model, oral administration of T863 significantly delayed fat absorption and resulted in lipid accumulation in the distal small intestine of mice, mimicking the effects of genetic ablation of DGAT1. In diet-induced obese mice, oral administration of T863 for 2 weeks caused weight loss, reduction in serum and liver triglycerides, and improved insulin sensitivity. In addition to the expected triglyceride-lowering activity, T863 also lowered serum cholesterol. Hepatic IRS2 protein was dramatically up-regulated in mice treated with T863, possibly contributing to improved insulin sensitivity. In differentiated 3T3-L1 adipocytes, T863 enhanced insulin-stimulated glucose uptake, suggesting a possible role for adipocytes to improve insulin sensitivity upon DGAT1 inhibition. These results reveal novel mechanistic insights into the insulin-sensitizing effects of DGAT1 inhibition in mouse models. Taken together, our study provides a comprehensive evaluation of a small molecule inhibitor for DGAT1 and suggests that pharmacological inhibition of DGAT1 holds promise in treating diverse metabolic disorders.
Asunto(s)
Diacilglicerol O-Acetiltransferasa/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Resistencia a la Insulina , Hígado/enzimología , Pérdida de Peso/efectos de los fármacos , Células 3T3-L1 , Administración Oral , Animales , Sitios de Unión , Diacilglicerol O-Acetiltransferasa/genética , Diacilglicerol O-Acetiltransferasa/metabolismo , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/farmacocinética , Humanos , Ratones , Ratones Obesos , Triglicéridos/sangreRESUMEN
Diacylglycerol acyltransferase (DGAT) catalyzes the final step of triacylglycerol (TAG) synthesis, and is considered as a potential target to control hypertriglyceridemia or other metabolic disorders. In this study, we found that the extract of rose petals suppressed TAG synthesis in cultured cells, and that the extract showed DGAT inhibitory action in a dose-dependent manner. Fractionation of the rose extract revealed that the DGAT inhibitory substances in the extract were ellagitannins; among them rugosin B, and D, and eusupinin A inhibited DGAT activity by 96, 82, and 84% respectively, at 10 µM. These substances did not inhibit the activities of other hepatic microsomal enzymes, glucose-6-phosphatase and HMG-CoA reductase, or pancreatic lipase, suggesting that ellagitannins inhibit DGAT preferentially. In an oral fat load test using mice, postprandial plasma TAG increase was suppressed by rose extract; TAG levels 2 h after the fat load were significantly lower in mice administered a fat emulsion containing rose extract than in control mice (446.3 ± 33.1 vs 345.3 ± 25.0 mg/dL, control vs rose extract group; P < 0.05). These results suggest that rose ellagitannins or rose extract could be beneficial in controlling lipid metabolism and used to improve metabolic disorders.