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1.
J Pharm Biomed Anal ; 243: 116056, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38428245

RESUMO

BGT-002, a new type of ATP-citrate lyase inhibitor, is a promising therapeutic for treatment of hypercholesterolemia. After an oral administration of BGT-002 to subjects, it underwent extensive metabolism and an acyl monoglucuronide (ZM326E-M2) on 1- carboxylic acid group was the major circulating metabolite. In this study, an LC-MS/MS method was developed and validated for the simultaneous determination of BGT-002 and ZM326E-M2 in plasma and the evaluation of their pharmacokinetic characteristics in humans. After extraction from the plasma by acetonitrile-induced protein precipitation, the analytes were separated on a Waters ACQUITY UPLC® BEH C18 column using acetonitrile and 2 mM ammonium acetate containing 0.1% formic acid as the mobile phase for gradient elution. Negative electrospray ionization was performed using multiple reaction monitoring (MRM) of m/z 501.3→325.4 for ZM326E-M2 and m/z 507.3→331.2 for D6-ZM326E-M2, and pseudo-MRM of m/z 325.3→325.3 for BGT-002 and m/z 331.3→331.3 for D6-ZM326E, respectively. The method was validated with respect to accuracy, precision, linearity, stability, selectivity, matrix effect, and recovery. The analytical range in human plasma was linear over a concentration range of 0.0500-50.0 µg/mL for BGT-002 and 0.0100-10.0 µg/mL for ZM326E-M2. The pharmacokinetic results showed that after a single oral administration of 100 mg BGT-002, the parent drug was rapidly absorbed with a mean time to peak concentration (tmax) of 1.13 h, compared with BGT-002, the tmax (4.00 h) of ZM326E-M2 was significantly delayed. The peak concentration and plasma exposure of ZM326E-M2 were about 14.1% and 19.5% of the parent drug, suggesting that attention should be paid to the safety and efficacy of ZM326E-M2 in clinical research.


Assuntos
Glucuronídeos , Espectrometria de Massas em Tandem , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Administração Oral , Acetonitrilas
2.
Sci Adv ; 10(6): eadj2752, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38324677

RESUMO

Exercise-induced activation of adenosine monophosphate-activated protein kinase (AMPK) and substrate phosphorylation modulate the metabolic capacity of mitochondria in skeletal muscle. However, the key effector(s) of AMPK and the regulatory mechanisms remain unclear. Here, we showed that AMPK phosphorylation of the folliculin interacting protein 1 (FNIP1) serine-220 (S220) controls mitochondrial function and muscle fuel utilization during exercise. Loss of FNIP1 in skeletal muscle resulted in increased mitochondrial content and augmented metabolic capacity, leading to enhanced exercise endurance in mice. Using skeletal muscle-specific nonphosphorylatable FNIP1 (S220A) and phosphomimic (S220D) transgenic mouse models as well as biochemical analysis in primary skeletal muscle cells, we demonstrated that exercise-induced FNIP1 (S220) phosphorylation by AMPK in muscle regulates mitochondrial electron transfer chain complex assembly, fuel utilization, and exercise performance without affecting mechanistic target of rapamycin complex 1-transcription factor EB signaling. Therefore, FNIP1 is a multifunctional AMPK effector for mitochondrial adaptation to exercise, implicating a mechanism for exercise tolerance in health and disease.


Assuntos
Proteínas Quinases Ativadas por AMP , Proteínas de Transporte , Camundongos , Animais , Fosforilação/fisiologia , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas de Transporte/metabolismo , Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo
3.
FASEB J ; 37(9): e23140, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37584647

RESUMO

The development of acute liver failure (ALF) is dependent on its local inducer. Inflammation is a high-frequency and critical factor that accelerates hepatocyte death and liver failure. In response to injury stress, the expression of the transcription factor hypoxia-inducible factor-1α (HIF-1α) in macrophages is promoted by both oxygen-dependent and oxygen-independent mechanisms, thus promoting the expression and secretion of the cytokine interleukin-1ß (IL-1ß). IL-1ß further induces hepatocyte apoptosis or necrosis by signaling through the receptor (IL-1R) on hepatocyte. HIF-1α knockout in macrophages or IL-1R knockout in hepatocytes protects against liver failure. However, whether HIF-1α inhibition in macrophages has a protective role in ALF is unclear. In this study, we revealed that the small molecule HIF-1α inhibitor PX-478 inhibits the expression and secretion of IL-1ß, but not tumor necrosis factor α (TNFα), in bone marrow-derived macrophages (BMDMs). PX-478 pretreatment alleviates liver injury in LPS/D-GalN-induced ALF mice by decreasing the hepatic inflammatory response. In addition, preventive or therapeutic administration of PX-478 combined with TNFα neutralizing antibody markedly improved LPS/D-GalN-induced ALF. Taken together, our data suggest that PX-478 administration leads to HIF-1α inhibition and decreased IL-1ß secretion in macrophages, which represents a promising therapeutic strategy for inflammation-induced ALF.


Assuntos
Falência Hepática Aguda , Fator de Necrose Tumoral alfa , Camundongos , Animais , Fator de Necrose Tumoral alfa/metabolismo , Lipopolissacarídeos/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/patologia , Macrófagos/metabolismo , Inflamação/metabolismo , Necrose/metabolismo , Oxigênio/metabolismo
4.
Acta Pharm Sin B ; 13(2): 739-753, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36873173

RESUMO

Hepatic cholesterol accumulation is an important contributor to hypercholesterolemia, which results in atherosclerosis and cardiovascular disease (CVD). ATP-citrate lyase (ACLY) is a key lipogenic enzyme that converts cytosolic citrate derived from tricarboxylic acid cycle (TCA cycle) to acetyl-CoA in the cytoplasm. Therefore, ACLY represents a link between mitochondria oxidative phosphorylation and cytosolic de novo lipogenesis. In this study, we developed the small molecule 326E with an enedioic acid structural moiety as a novel ACLY inhibitor, and its CoA-conjugated form 326E-CoA inhibited ACLY activity with an IC50 = 5.31 ± 1.2 µmol/L in vitro. 326E treatment reduced de novo lipogenesis, and increased cholesterol efflux in vitro and in vivo. 326E was rapidly absorbed after oral administration, exhibited a higher blood exposure than that of the approved ACLY inhibitor bempedoic acid (BA) used for hypercholesterolemia. Chronic 326E treatment in hamsters and rhesus monkeys resulted in remarkable improvement of hyperlipidemia. Once daily oral administration of 326E for 24 weeks prevented the occurrence of atherosclerosis in ApoE-/- mice to a greater extent than that of BA treatment. Taken together, our data suggest that inhibition of ACLY by 326E represents a promising strategy for the treatment of hypercholesterolemia.

5.
Acta Pharmacol Sin ; 43(5): 1141-1155, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35105958

RESUMO

Mitochondrial biology and behavior are central to the physiology of liver. Multiple mitochondrial quality control mechanisms remodel mitochondrial homeostasis under physiological and pathological conditions. Mitochondrial dysfunction and damage induced by overnutrition lead to oxidative stress, inflammation, liver cell death, and collagen production, which advance hepatic steatosis to nonalcoholic steatohepatitis (NASH). Accumulating evidence suggests that specific interventions that target mitochondrial homeostasis, including energy metabolism, antioxidant effects, and mitochondrial quality control, have emerged as promising strategies for NASH treatment. However, clinical translation of these findings is challenging due to the complex and unclear mechanisms of mitochondrial homeostasis in the pathophysiology of NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Biologia , Homeostase , Humanos , Fígado/metabolismo , Mitocôndrias/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo
6.
Acta Pharmacol Sin ; 42(4): 585-592, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32724176

RESUMO

Dyslipidemia is a chronic metabolic disease characterized by elevated levels of lipids in plasma. Recently, various studies demonstrate that the increased activity of adenosine 5'-monophosphate-activated protein kinase (AMPK) causes health benefits in energy regulation. Thus, great efforts have been made to develop AMPK activators as a metabolic syndrome treatment. In the present study, we investigated the effects of the AMPK activator C24 on dyslipidemia and the potential mechanisms. We showed that C24 (5-40 µM) dose-dependently increased the phosphorylation of AMPKα and acetyl-CoA carboxylase (ACC), and inhibited lipogenesis in HepG2 cells. Using compound C, an AMPK inhibitor, or hepatocytes isolated from liver tissue-specific AMPK knockout AMPKα1α2fl/fl;Alb-cre mice (AMPK LKO), we demonstrated that the lipogenesis inhibition of C24 was dependent on hepatic AMPK activation. In rabbits with high-fat and high-cholesterol diet-induced dyslipidemia, administration of C24 (20, 40, and 60 mg · kg-1· d-1, ig, for 4 weeks) dose-dependently decreased the content of TG, total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) in plasma and played a role in protecting against hepatic dysfunction by decreasing lipid accumulation. A lipid-lowering effect was also observed in high-fat and high-cholesterol diet-fed hamsters. In conclusion, our results demonstrate that the small molecular AMPK activator C24 alleviates hyperlipidemia and represents a promising compound for the development of a lipid-lowering drug.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Dislipidemias/tratamento farmacológico , Ativadores de Enzimas/uso terapêutico , Hipolipemiantes/uso terapêutico , Lipogênese/efeitos dos fármacos , Oxindóis/uso terapêutico , Animais , Dieta Hiperlipídica , Dislipidemias/enzimologia , Células Hep G2 , Humanos , Fígado/efeitos dos fármacos , Masculino , Mesocricetus , Camundongos Endogâmicos C57BL , Coelhos
7.
Acta Pharmacol Sin ; 42(2): 272-281, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32699264

RESUMO

Insulin resistance is a major cause of type 2 diabetes and metabolic syndrome. Macrophage infiltration into obese adipose tissue promotes inflammatory responses that contribute to the pathogenesis of insulin resistance. Suppression of adipose tissue inflammatory responses is postulated to increase insulin sensitivity in obese patients and animals. Sarsasapogenin (ZGY) is one of the metabolites of timosaponin AIII in the gut, which has been shown to exert anti-inflammatory action. In this study, we investigated the effects of ZGY treatment on obesity-induced insulin resistance in mice. We showed that pretreatment with ZGY (80 mg·kg-1·d-1, ig, for 18 days) significantly inhibited acute adipose tissue inflammatory responses in LPS-treated mice. In high-fat diet (HFD)-fed obese mice, oral administration of ZGY (80 mg·kg-1·d-1, for 6 weeks) ameliorated insulin resistance and alleviated inflammation in adipose tissues by reducing the infiltration of macrophages. Furthermore, we demonstrated that ZGY not only directly inhibited inflammatory responses in macrophages and adipocytes, but also interrupts the crosstalk between macrophages and adipocytes in vitro, improving adipocyte insulin resistance. The insulin-sensitizing and anti-inflammatory effects of ZGY may result from inactivation of the IKK /NF-κB and JNK inflammatory signaling pathways in adipocytes. Collectively, our findings suggest that ZGY ameliorates insulin resistance and alleviates the adipose inflammatory state in HFD mice, suggesting that ZGY may be a potential agent for the treatment of insulin resistance and obesity-related metabolic diseases.


Assuntos
Inflamação/tratamento farmacológico , Resistência à Insulina , Obesidade/tratamento farmacológico , Espirostanos/farmacologia , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/patologia , Tecido Adiposo/efeitos dos fármacos , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Dieta Hiperlipídica , Modelos Animais de Doenças , Inflamação/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/complicações , Células RAW 264.7 , Espirostanos/administração & dosagem
8.
Cell Death Dis ; 11(9): 770, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943612

RESUMO

Gypenosides, extracts of Gynostemma yixingense, have been traditionally prescribed to improve metabolic syndrome in Asian folk and local traditional medicine hospitals. However, the mechanism of its action remains unclarified. In this work, our results indicated that chronic administration of 2α-OH-protopanoxadiol (GP2), a metabolite of gypenosides in vivo, protected mice from high-fat diet-induced obesity and improved glucose tolerance by improving intestinal L-cell function. Mechanistically, GP2 treatment inhibited the enzymatic activity of bile salt hydrolase and modulated the proportions of the gut microbiota, which led to an increase in the accumulation of tauro-ß-muricholic acid (TßMCA) in the intestine. TßMCA induced GLP-1 production and secretion by reducing the transcriptional activity of nuclear receptor farnesoid X receptor (FXR). Transplantation of GP2-remodelled fecal microbiota into antibiotic-treated mice also increased the intestinal TßMCA content and improved intestinal L-cell function. These findings demonstrate that GP2 ameliorates metabolic syndrome at least partly through the intestinal FXR/GLP-1 axis via gut microbiota remodelling and also suggest that GP2 may serve as a promising oral therapeutic agent for metabolic syndrome.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Intestinos/efeitos dos fármacos , Síndrome Metabólica/tratamento farmacológico , Proteínas de Ligação a RNA/metabolismo , Ácido Taurocólico/análogos & derivados , Animais , Dieta Hiperlipídica , Desenho de Fármacos , Glucagon/metabolismo , Gynostemma/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Extratos Vegetais/metabolismo , RNA Ribossômico 16S/metabolismo , Ácido Taurocólico/química
9.
Acta Pharmacol Sin ; 41(6): 813-824, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31949294

RESUMO

Berberine (BBR) exhibits diverse bioactivities, including anticancer activity; but its poor druggability limits its applications. In this study, we designed and synthesized a series of 9-O position modified BBR derivatives aiming to improve its cell permeability and anticancer activity, utilizing a long alkyl chain branched by hydroxyl group and methoxycarbonyl group. Among these compounds, B10 showed 3.6-fold higher intracellular concentration than BBR, as well as 60-fold increased anti-proliferation activity against human lung cancer A549 cells compared with BBR. Treatment with B10 (1, 2 µM) induced apoptosis of A549 cells. Further investigations showed that B10 treatment dose-dependently affected mitochondrial functions, including oxygen consumption rate (OCR), mitochondrial membrane potential (MMP) and the morphology of mitochondria in A549 cells. Therefore, this work offers a new way for BBR structural modification through improving cell membrane permeability to affect mitochondrial functions and potential anti-tumor therapy in the future.


Assuntos
Antineoplásicos/farmacologia , Berberina/farmacologia , Células A549 , Antineoplásicos/química , Berberina/análogos & derivados , Berberina/química , Permeabilidade da Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Imagem Óptica , Relação Estrutura-Atividade , Células Tumorais Cultivadas
10.
Bioorg Med Chem Lett ; 30(2): 126790, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31744674

RESUMO

Adenosine monophosphate-activated protein kinase (AMPK) has been considered as a promising drug target for its regulation in both glucose and lipid metabolism. Mogrol was originally identified from high throughput screening as a small molecule activator of AMPK subtype α2ß1γ1. In order to enhance its potency on AMPK and summarize the structure-activity relationships, a series of mogrol derivatives were designed, synthesized and evaluated in pharmacological AMPK activation assays. The results showed that the amine derivatives at the 24-position can improve the potency. Among them, compounds 3 and 4 exhibited the best potency (EC50: 0.15 and 0.14 µM) which was 20 times more potent than mogrol (EC50: 3.0 µM).


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Desenho de Fármacos , Ativadores de Enzimas/síntese química , Triterpenos/metabolismo , Proteínas Quinases Ativadas por AMP/química , Regulação Alostérica/efeitos dos fármacos , Cucurbitaceae/química , Cucurbitaceae/metabolismo , Ativadores de Enzimas/metabolismo , Ativadores de Enzimas/farmacologia , Humanos , Relação Estrutura-Atividade , Triterpenos/farmacologia
11.
Diabetes ; 68(12): 2197-2209, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31471292

RESUMO

Uncoupling of mitochondrial respiration by chemical uncouplers has proven effective in ameliorating obesity, insulin resistance, and hyperglycemia. However, development of uncoupler-based therapy remains challenging due to its potentially lethal adverse effects. Here, we identify pyruvate dehydrogenase (PDH) as a key modifier of the toxicity profile of 2, 4-dinitrophenol (DNP), a prototypical mitochondrial uncoupler. PDH activation by dichloroacetic acid (DCA) protects mice from DNP-induced hyperlactacidemia, hyperthermia, and death while preserving the ability of DNP to promote fuel oxidation and improve insulin sensitivity in mice. Mechanistically, PDH activation switches on mitochondrial glucose oxidation to accommodate increased glycolytic flux, leading to reduced lactate secretion during uncoupler treatments. We devised a chemical screening strategy and discovered compound 6j as a dual-action compound that simultaneously activates PDH and uncouples mitochondrial respiration. Compound 6j exhibits an excellent efficacy and safety profile in restoring glucose homeostasis in diabetic mice. This work establishes a new principle to safely harness the power of chemical uncouplers for the treatment of metabolic disease.


Assuntos
Diabetes Mellitus Experimental , Hiperglicemia , Animais , Glucose , Camundongos , Oxirredutases , Complexo Piruvato Desidrogenase , Piruvatos
12.
Osong Public Health Res Perspect ; 10(3): 187-201, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31263668

RESUMO

OBJECTIVES: This study aimed to extend an epidemiological model (SEIHFR) to analyze epidemic trends, and evaluate intervention efficacy. METHODS: SEIHFR was modified to examine disease transmission dynamics after vaccination for the Ebola outbreak. Using existing data from Liberia, sensitivity analysis of various epidemic scenarios was used to inform the model structure, estimate the basic reproduction number ℜ0 and investigate how the vaccination could effectively change the course of the epidemic. RESULTS: If a randomized mass vaccination strategy was adopted, vaccines would be administered prophylactically or as early as possible (depending on the availability of vaccines). An effective vaccination rate threshold for Liberia was estimated as 48.74% among susceptible individuals. If a ring vaccination strategy was adopted to control the spread of the Ebola virus, vaccines would be given to reduce the transmission rate improving the tracing rate of the contact persons of an infected individual. CONCLUSION: The extended SEIHFR model predicted the total number of infected cases, number of deaths, number of recoveries, and duration of outbreaks among others with different levels of interventions such as vaccination rate. This model may be used to better understand the spread of Ebola and develop strategies that may achieve a disease-free state.

13.
Acta Pharmacol Sin ; 39(10): 1622-1632, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29795358

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a clinical syndrome characterized by hepatic steatosis. NAFLD is closely linked to obesity, insulin resistance and dyslipidemia. AMP-activated protein kinase (AMPK) functions as an energy sensor and plays a central role in regulating lipid metabolism. In this study, we identified a series of novel pyrazolone AMPK activators using a homogeneous time-resolved fluorescence assay (HTRF) based on the AMPKα2ß1γ1 complex. Compound 29 (C29) is a candidate compound that directly activated the kinase domain of AMPK with an EC50 value of 2.1-0.2 µmol/L and acted as a non-selective activator of AMPK complexes. Treatment of HepG2 cells with C29 (20, 40 µmol/L) dose-dependently inhibited triglyceride accumulation. Chronic administration of C29 (10, 30 mg/kg every day, po, for 5 weeks) significantly improved lipid metabolism in both the liver and the plasma of ob/ob mice. These results demonstrate that the AMPK activators could be part of a novel treatment approach for NAFLD and associated metabolic disorders.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Ativadores de Enzimas/uso terapêutico , Lipogênese/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Pirazolonas/uso terapêutico , Proteínas Quinases Ativadas por AMP/química , Animais , Cães , Ativadores de Enzimas/química , Ativadores de Enzimas/metabolismo , Haplorrinos , Células Hep G2 , Humanos , Fígado/metabolismo , Camundongos , Microssomos Hepáticos/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Domínios Proteicos/efeitos dos fármacos , Pirazolonas/química , Pirazolonas/metabolismo , Ratos , Relação Estrutura-Atividade
14.
Front Physiol ; 9: 122, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29515462

RESUMO

Obesity occurs when excess energy accumulates in white adipose tissue (WAT), whereas brown adipose tissue (BAT), which is specialized in dissipating energy through thermogenesis, potently counteracts obesity. White adipocytes can be converted to thermogenic "brown-like" cells (beige cells; WAT browning) under various stimuli, such as cold exposure. AMP-activated protein kinase (AMPK) is a crucial energy sensor that regulates energy metabolism in multiple tissues. However, the role of AMPK in adipose tissue function, especially in the WAT browning process, is not fully understood. To illuminate the effect of adipocyte AMPK on energy metabolism, we generated Adiponectin-Cre-driven adipose tissue-specific AMPK α1/α2 KO mice (AKO). These AKO mice were cold intolerant and their inguinal WAT displayed impaired mitochondrial integrity and biogenesis, and reduced expression of thermogenic markers upon cold exposure. High-fat-diet (HFD)-fed AKO mice exhibited increased adiposity and exacerbated hepatic steatosis and fibrosis and impaired glucose tolerance and insulin sensitivity. Meanwhile, energy expenditure and oxygen consumption were markedly decreased in the AKO mice both in basal conditions and after stimulation with a ß3-adrenergic receptor agonist, CL 316,243. In contrast, we found that in HFD-fed obese mouse model, chronic AMPK activation by A-769662 protected against obesity and related metabolic dysfunction. A-769662 alleviated HFD-induced glucose intolerance and reduced body weight gain and WAT expansion. Notably, A-769662 increased energy expenditure and cold tolerance in HFD-fed mice. A-769662 treatment also induced the browning process in the inguinal fat depot of HFD-fed mice. Likewise, A-769662 enhanced thermogenesis in differentiated inguinal stromal vascular fraction (SVF) cells via AMPK signaling pathway. In summary, a lack of adipocyte AMPKα induced thermogenic impairment and obesity in response to cold and nutrient-overload, respectively, whereas chronic AMPK activation by A-769662 promoted WAT browning in inguinal WAT and protected against HFD-induced obesity and related metabolic dysfunction. These findings reveal a vital role for adipocyte AMPK in regulating the browning process in inguinal WAT and in maintaining energy homeostasis, which suggests that the targeted activation of adipocyte AMPK may be a promising strategy for anti-obesity therapy.

15.
Mol Cell Proteomics ; 16(7): 1324-1334, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28450421

RESUMO

Type 2 diabetes (T2D) is a major chronic healthcare concern worldwide. Emerging evidence suggests that a histone-modification-mediated epigenetic mechanism underlies T2D. Nevertheless, the dynamics of histone marks in T2D have not yet been carefully analyzed. Using a mass spectrometry-based label-free and chemical stable isotope labeling quantitative proteomic approach, we systematically profiled liver histone post-translational modifications (PTMs) in a prediabetic high-fat diet-induced obese (DIO) mouse model. We identified 170 histone marks, 30 of which were previously unknown. Interestingly, about 30% of the histone marks identified in DIO mouse liver belonged to a set of recently reported lysine acylation modifications, including propionylation, butyrylation, malonylation, and succinylation, suggesting possible roles of these newly identified histone acylations in diabetes and obesity. These histone marks were detected without prior affinity enrichment with an antibody, demonstrating that the histone acylation marks are present at reasonably high stoichiometry. Fifteen histone marks differed in abundance in DIO mouse liver compared with liver from chow-fed mice in label-free quantification, and six histone marks in stable isotope labeling quantification. Analysis of hepatic histone modifications from metformin-treated DIO mice revealed that metformin, a drug widely used for T2D, could reverse DIO-stimulated histone H3K36me2 in prediabetes, suggesting that this mark is likely associated with T2D development. Our study thus offers a comprehensive landscape of histone marks in a prediabetic mouse model, provides a resource for studying epigenetic functions of histone modifications in obesity and T2D, and suggest a new epigenetic mechanism for the physiological function of metformin.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Histonas/metabolismo , Fígado/metabolismo , Obesidade/induzido quimicamente , Proteômica/métodos , Acilação/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Epigênese Genética , Código das Histonas , Histonas/efeitos dos fármacos , Marcação por Isótopo , Espectrometria de Massas , Metformina/farmacologia , Camundongos , Camundongos Obesos , Obesidade/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos
16.
Bioorg Med Chem ; 24(12): 2688-96, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27132866

RESUMO

As a follow-up discovery of AMPK activators from natural products, 20S-dammar-24-en-2α,3ß,12ß,20-tetrol (GP, 1), a dammarane-type triterpenoid, was found to have some favorable metabolic effects on dyslipidemia in Golden Syrian hamsters, and activate AMPKα2ß1γ1 by around 2.4 fold with an EC50 of 5.1µM on molecular level. In order to enhance its potency at AMPK and structure-activity relationship study, GP derivatives were designed, synthesized, and evaluated in pharmacological AMPK activation assays. Structure-activity relationship analysis showed that amine at the 24-position (groups I-IV) effectively and significantly increased the potency and efficacy. GP derivatives 12 and 17-19 exhibited better potency (EC50: 0.3, 0.8, 0.8, and 1.0µM) and efficacy (fold: 3.2, 2.7, 3.0, and 2.8) in the activation of AMPK heterotrimer α2ß1γ1 than positive control (AMP, EC50: 1.6µM, fold: 3.2). Furthermore, the most potent compounds 12 and 17 obviously inhibited glucose output through increasing the phosphorylation of AMPK, without affecting mitochondrial membrane potential or producing cytotoxicity.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Ativação Enzimática/efeitos dos fármacos , Triterpenos/química , Triterpenos/farmacologia , Animais , Glucose/metabolismo , Células Hep G2 , Humanos , Masculino , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Multimerização Proteica/efeitos dos fármacos , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade , Damaranos
17.
Math Biosci ; 267: 134-48, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26192388

RESUMO

In this paper, we study a strongly coupled reaction-diffusion system describing three interacting species in a food chain model, where the third species preys on the second one and simultaneously the second species preys on the first one. An intra-species competition b2 among the second predator is introduced to the food chain model. This parameter produces some very interesting result in linear stability and Turing instability. We first show that the unique positive equilibrium solution is locally asymptotically stable for the corresponding ODE system when the intra-species competition exists among the second predator. The positive equilibrium solution remains linearly stable for the reaction diffusion system without cross diffusion, hence it does not belong to the classical Turing instability scheme. But it becomes linearly unstable only when cross-diffusion also plays a role in the reaction-diffusion system, hence the instability is driven solely from the effect of cross diffusion. Our results also exhibit some interesting combining effects of cross-diffusion, intra-species competitions and inter-species interactions. Numerically, we conduct a one parameter analysis which illustrate how the interactions change the existence of stable equilibrium, limit cycle, and chaos. Some interesting dynamical phenomena occur when we perform analysis of interactions in terms of self-production of prey and intra-species competition of the middle predator. By numerical simulations, it illustrates the existence of nonuniform steady solutions and new patterns such as spot patterns, strip patterns and fluctuations due to the diffusion and cross diffusion in two-dimension.


Assuntos
Cadeia Alimentar , Animais , Simulação por Computador , Ecossistema , Modelos Lineares , Conceitos Matemáticos , Modelos Biológicos , Dinâmica Populacional , Comportamento Predatório , Especificidade da Espécie
18.
Acta Pharmacol Sin ; 36(4): 483-96, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25832429

RESUMO

AIM: Sterol-regulatory element binding proteins (SREBPs) are major transcription factors that regulate liver lipid biosynthesis. In this article we reported a novel synthetic compound 2-(3-benzoylthioureido)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylic acid (ZJ001) that inhibited the SREBP-1c pathway, and effectively reduced hepatic lipid accumulation in diet-induced obesity (DIO) mice. METHODS: A luciferase reporter driven by an SRE-containing promoter transfected into HepG2 cells was used to discover the compound. Two approaches were used to evaluate the lipid-lowering effects of ZJ001: (1) diet-induced obesity (DIO) mice that were treated with ZJ001 (15 mg·kg(-1)·d(-1), po) for 7 weeks; and (2) HepG2 cells and primary hepatocytes used as in vitro models. RESULTS: ZJ001 (10, 20 µmol/L) dose-dependently inhibited the activity of SRE-containing promoter. ZJ001 administration ameliorated lipid metabolism and improved glucose tolerance in DIO mice, accompanied by significantly reduced mRNA levels of SREBP-1C and SREBP-2, and their downstream genes. In HepG2 cells and insulin-treated hepatocytes, ZJ001 (10-40 µmol/L) dose-dependently inhibited lipid synthesis, and reduced mRNA levels of SREBP-1C and SREBP-2, and their downstream genes. Furthermore, ZJ001 dose-dependently increased the phosphorylation of AMPK and regulatory-associated protein of mTOR (Raptor), and suppressed the phosphorylation of mTOR in insulin-treated hepatocytes. Moreover, ZJ001 increased the ADP/ATP ratio in insulin-treated hepatocytes. CONCLUSION: ZJ001 exerts multiple beneficial effects in diet-induced obesity mice. Its lipid-lowering effects may result from the suppression of mTORC1, which regulates SREBP-1c transcription. The results suggest that the SREBP-1c pathway may be a potential therapeutic target for the treatment of lipid metabolic disorders.


Assuntos
Fármacos Antiobesidade/uso terapêutico , Metabolismo dos Lipídeos/efeitos dos fármacos , Obesidade/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Tiofenos/uso terapêutico , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Fármacos Antiobesidade/química , Células Cultivadas , Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/enzimologia , Hepatócitos/metabolismo , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Endogâmicos C57BL , Complexos Multiproteicos/metabolismo , Obesidade/genética , Obesidade/metabolismo , Ratos , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Tiofenos/química
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