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1.
Molecules ; 26(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34443427

RESUMO

Pterostilbene, a natural metabolite of resveratrol, has been indicated as a potent anticancer molecule. Recently, several pterostilbene derivatives have been reported to exhibit better anticancer activities than that of the parent pterostilbene molecule. In the present study, a series of pterostilbene derivatives were designed and synthesized by the hybridization of pterostilbene, chalcone, and cinnamic acid. The cytotoxic effect of these hybrid molecules was determined using two oral cancer cell lines, HSC-3 and OECM-1. (E)-3-(2-((E)-4-Hydroxystyryl)-4,6-dimethoxyphenyl)-1-(2-methoxyphenyl)prop-2-en-1-one (4d), with IC50 of 16.38 and 18.06 µM against OECM-1 and HSC-3, respectively, was selected for further anticancer mechanism studies. Results indicated that compound 4d effectively inhibited cell proliferation and induced G2/M cell cycle arrest via modulating p21, cyclin B1, and cyclin A2. Compound 4d ultimately induced cell apoptosis by reducing the expression of Bcl-2 and surviving. In addition, cleavage of PARP and caspase-3 were enhanced following the treatment of compound 4d with increased dose. To conclude, a number of pterostilbene derivatives were discovered to possess potent anticancer potentials. Among them, compound 4d was the most active, more active than the parent pterostilbene.


Assuntos
Antineoplásicos/farmacologia , Chalcona/farmacologia , Estilbenos/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Chalcona/química , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Poli(ADP-Ribose) Polimerases/metabolismo , Estilbenos/química , Relação Estrutura-Atividade
2.
Chem Biol Interact ; 345: 109572, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34217687

RESUMO

Oxidized low-density lipoprotein (ox-LDL) not only causes hyperlipidemia and contributes to atherosclerosis but also induces the endothelial dysfunction that leads to cardiovascular diseases. The nuclear factor-kappa B (NF-κB) pathway plays a key role in many chronic disorders and is a transcriptional factor in various inflammatory responses. The present study aimed to investigate the synergistic effects of pelargonic acid vanillylamide (PAVA) and rosuvastatin (RSV) on ox-LDL-induced inflammatory responses in human vascular endothelial cells (HUV-EC-C). HUV-EC-C were pretreated with PAVA or RSV and their combination for 2 h followed by ox-LDL for 24 h. The MTT assay was used to measure mitochondrial function. The DCFH-DA assay was used to evaluate oxidative phosphorylation, and western blotting was used to measured NF-κB/NLRP3 and related signaling pathways in HUV-EC-C. Ox-LDL induced lectin-type oxidized LDL receptor 1 (LOX-1) expression, NADPH oxidase 4 activation, and the overexpression of reactive oxygen species, which were inhibited by pretreatment with the combination of PAVA and RSV. Moreover, PAVA and RSV inhibited ox-LDL-induced NF-κBp65 activation. Ox-LDL induced NF-κB/NLRP3 pathway activation by inducing C-reactive protein expression, NLRP3 activation, caspase-1 activation, and IL-1ß secretion, which were inhibited by pretreatment with the combination of PAVA and RSV. The combination of PAVA and RSV reduced ox-LDL-induced recruitment of monocytes to the site of inflammation, inhibited activation of the NLRP3 inflammasome, and ameliorated the impairment of cell-cell junctions through the NF-κB pathway. Our results suggest that the synergistic effects of PAVA and RSV provide a novel mechanism for the treatment of cardiovascular diseases.


Assuntos
Benzilaminas/farmacologia , Citoproteção/efeitos dos fármacos , Ácidos Graxos/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Junções Intercelulares/efeitos dos fármacos , Lipoproteínas LDL/farmacologia , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Caspase 1/metabolismo , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Inflamassomos/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
3.
Int J Mol Sci ; 22(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203724

RESUMO

Numerous studies have shown that hedgehog inhibitors (iHHs) only partially block the growth of tumor cells, especially in vivo. Leukemia often expands in a nutrient-depleted environment (bone marrow and thymus). In order to identify putative signaling pathways implicated in the adaptive response to metabolically adverse conditions, we executed quantitative phospho-proteomics in T-cell acute lymphoblastic leukemia (T-ALL) cells subjected to nutrient-depleted conditions (serum starvation). We found important modulations of peptides phosphorylated by critical signaling pathways including casein kinase, mammalian target of rapamycin, and 5'AMP-activated kinase (AMPK). Surprisingly, in T-ALL cells, AMPK signaling was the most consistently downregulated pathway under serum-depleted conditions, and this coincided with increased GLI1 expression and sensitivity to iHHs, especially the GLI1/2 inhibitor GANT-61. Increased sensitivity to GANT-61 was also found following genetic inactivation of the catalytic subunit of AMPK (AMPKα1) or pharmacological inhibition of AMPK by Compound C. Additionally, patient-derived xenografts showing high GLI1 expression lacked activated AMPK, suggesting an important role for this signaling pathway in regulating GLI1 protein levels. Further, joint targeting of HH and AMPK signaling pathways in T-ALL cells by GANT-61 and Compound C significantly increased the therapeutic response. Our results suggest that metabolic adaptation that occurs under nutrient starvation in T-ALL cells increases responsiveness to HH pathway inhibitors through an AMPK-dependent mechanism and that joint therapeutic targeting of AMPK signaling and HH signaling could represent a valid therapeutic strategy in rapidly expanding tumors where nutrient availability becomes limiting.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Hedgehog/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Transdução de Sinais , Proteínas Quinases Ativadas por AMP/genética , Morte Celular/efeitos dos fármacos , Meios de Cultura Livres de Soro/farmacologia , Ativação Enzimática/efeitos dos fármacos , Humanos , Células Jurkat , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Piridinas/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteína GLI1 em Dedos de Zinco/metabolismo
4.
Nutrients ; 13(7)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209137

RESUMO

D-Pinitol (DPIN) is a natural occurring inositol capable of activating the insulin pathway in peripheral tissues, whereas this has not been thoroughly studied in the central nervous system. The present study assessed the potential regulatory effects of DPIN on the hypothalamic insulin signaling pathway. To this end we investigated the Phosphatidylinositol-3-kinase (PI3K)/Protein Kinase B (Akt) signaling cascade in a rat model following oral administration of DPIN. The PI3K/Akt-associated proteins were quantified by Western blot in terms of phosphorylation and total expression. Results indicate that the acute administration of DPIN induced time-dependent phosphorylation of PI3K/Akt and its related substrates within the hypothalamus, indicating an activation of the insulin signaling pathway. This profile is consistent with DPIN as an insulin sensitizer since we also found a decrease in the circulating concentration of this hormone. Overall, the present study shows the pharmacological action of DPIN in the hypothalamus through the PI3K/Akt pathway when giving in fasted animals. These findings suggest that DPIN might be a candidate to treat brain insulin-resistance associated disorders by activating insulin response beyond the insulin receptor.


Assuntos
Hipotálamo/metabolismo , Inositol/análogos & derivados , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Administração Oral , Animais , Glicemia/metabolismo , Ativação Enzimática/efeitos dos fármacos , Glucagon/sangue , Homeostase , Hipotálamo/efeitos dos fármacos , Inositol/administração & dosagem , Inositol/sangue , Inositol/química , Inositol/farmacologia , Insulina/sangue , Insulina/metabolismo , Resistência à Insulina , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Fosforilação/efeitos dos fármacos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
5.
Int Heart J ; 62(4): 910-918, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34276002

RESUMO

Calcium antagonists are used for coronary spastic angina (CSA) treatment. We previously identified a phospholipase C (PLC) -δ1 gene variant that results in enhanced PLC activity in patients with CSA and developed a CSA animal model by generating vascular smooth muscle cell-specific human variant PLC-δ1 overexpression (PLC-TG) mice. In this study, we investigated the molecular mechanism of CSA using the PLC-TG mice and the inhibitory effect of a calcium antagonist, diltiazem hydrochloride (DL).We treated the PLC-TG and wild-type (WT) mice with oral DL or trichlormethiazide (TM) (control) for 2 weeks. Ergometrine injection-induced coronary spasm was observed on the electrocardiogram in all 5 PLC-TG mice treated with TM, but only in 1 of 5 PLC-TG mice treated with DL. Voltage-dependent calcium channel (Cav1.2) phosphorylation and protein kinase C (PKC) activity were enhanced in the aortas of PLC-TG mice treated with TM. DL treatment significantly inhibited Cav1.2 phosphorylation and PKC activity. Although total Cav1.2 expression was similar between WT and PLC-TG mice treated with TM, DL treatment significantly increased its expression in PLC-TG mice. Furthermore, its expression remained high after DL discontinuation. DL and PKC inhibitor suppressed intracellular calcium response to acetylcholine in cultured rat aortic smooth muscle cells transfected with variant PLC-δ1.These results indicate that enhanced PLC activity causes coronary spasm, presumably via enhanced Cav1.2 phosphorylation and PKC activity, both of which were inhibited by DL. Enhanced total Cav1.2 expression after DL discontinuation and high PKC activity may be an important mechanism underlying the calcium antagonist withdrawal syndrome.


Assuntos
Bloqueadores dos Canais de Cálcio/uso terapêutico , Canais de Cálcio Tipo L/metabolismo , Vasoespasmo Coronário/tratamento farmacológico , Diltiazem/uso terapêutico , Proteína Quinase C/metabolismo , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Vasoespasmo Coronário/metabolismo , Diltiazem/farmacologia , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Masculino , Camundongos Transgênicos , Fosforilação/efeitos dos fármacos
6.
Int J Mol Sci ; 22(9)2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34067020

RESUMO

Current available therapies for pancreatic ductal adenocarcinoma (PDAC) provide minimal overall survival benefits and cause severe adverse effects. We have identified a novel molecule AS-10, a selenazolidine-bis-aspirinyl derivative, that was two to three orders of magnitude more potent than aspirin and at least one to two orders of magnitude more potent than gemcitabine in inhibiting PDAC cancer cell growth/viability against three PDAC cell lines while sparing mouse embryonic fibroblasts in the same exposure range. In Panc-1 cells, AS-10 induced apoptosis without necrosis, principally through caspase-3/7 cascade and reactive oxygen species, in addition to an induction of G1 cell cycle block. Transcriptomic profiling with RNA-seq indicated the top responses to AS-10 exposure as CDKN1A (P21Cip1), CCND1, and nuclear transcription factor-kappa B (NF-κB) complex and the top functions as cell cycle, cell death, and survival without inducing the DNA damage gene signature. AS-10 pretreatment (6 h) decreased cytokine tumor necrosis factor-alpha (TNF-α)-stimulated NF-κB nuclear translocation, DNA binding activity, and degradation of cytosolic inhibitor of κB (IκB) protein. As NF-κB activation in PDAC cells confers resistance to gemcitabine, the AS-10 combination with gemcitabine increased the in vitro cytotoxicity more than the additivity of both compounds. Overall, our results suggest AS-10 may be a promising drug lead for PDAC, both as a single agent and in combination therapy.


Assuntos
Adenocarcinoma/patologia , Apoptose , Aspirina/farmacologia , Carcinoma Ductal Pancreático/patologia , Desoxicitidina/análogos & derivados , Pontos de Checagem da Fase G1 do Ciclo Celular , NF-kappa B/metabolismo , Neoplasias Pancreáticas/patologia , Acetilcisteína/farmacologia , Adenocarcinoma/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Aspirina/química , Carcinoma Ductal Pancreático/genética , Caspases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citocinas/metabolismo , Desoxicitidina/farmacologia , Ativação Enzimática/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Neoplasias Pancreáticas/genética , Transdução de Sinais/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética
7.
Int J Mol Sci ; 22(9)2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-34062977

RESUMO

Chronic inflammation has been associated with several chronic diseases, such as age-related macular degeneration (AMD). The NLRP3 inflammasome is a central proinflammatory signaling complex that triggers caspase-1 activation leading to the maturation of IL-1ß. We have previously shown that the inhibition of the chaperone protein, Hsp90, prevents NLRP3 activation in human retinal pigment epithelial (RPE) cells; these are cells which play a central role in the pathogenesis of AMD. In that study, we used a well-known Hsp90 inhibitor geldanamycin, but it cannot be used as a therapy due to its adverse effects, including ocular toxicity. Here, we have tested the effects of a novel Hsp90 inhibitor, TAS-116, on NLRP3 activation using geldanamycin as a reference compound. Using our existing protocol, inflammasome activation was induced in IL-1α-primed ARPE-19 cells with the proteasome and autophagy inhibitors MG-132 and bafilomycin A1, respectively. Intracellular caspase-1 activity was determined using a commercial caspase-1 activity kit and the FLICA assay. The levels of IL-1ß were measured from cell culture medium samples by ELISA. Cell viability was monitored by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test and lactate dehydrogenase (LDH) measurements. Our findings show that TAS-116 could prevent the activation of caspase-1, subsequently reducing the release of mature IL-1ß. TAS-116 has a better in vitro therapeutic index than geldanamycin. In summary, TAS-116 appears to be a well-tolerated Hsp90 inhibitor, with the capability to prevent the activation of the NLRP3 inflammasome in human RPE cells.


Assuntos
Benzamidas/farmacologia , Células Epiteliais/metabolismo , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Pirazóis/farmacologia , Epitélio Pigmentado da Retina/patologia , Benzoquinonas/farmacologia , Caspase 1/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Interleucina-1beta/metabolismo , Interleucina-8/metabolismo , Lactamas Macrocíclicas/farmacologia
8.
Arch Microbiol ; 203(7): 4367-4383, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34120198

RESUMO

The present study was undertaken to investigate the arsenite (As III)-induced changes in the diazotrophic cyanobacterium Anabaena PCC 7120. It was observed that the growth of cyanobacterial decreased with increase in As (III) concentration. The cells exposed to As (III) showed morphological variation (deformity) due to the formation of deeper constrictions in vegetative cells. Strain showed increased heterocyst differentiation (1.6-fold higher) whereas decreased nitrogenase activity at the concentration of 40 ppm As (III). The activities of NR, NiR, urease and GS decreased with increase in As (III) concentrations and attained their minimum levels at 40 ppm of As (III). The Ca2+-dependent ATPase activity increased with increase in As (III) concentration and attained its about 2.72-fold higher level at 40 ppm of As (III). In contrast, sharp decline in Mg2+-dependent ATPase activity (28%) was recorded at 1 ppm of As (III) over untreated control. The rates of photosynthetic O2 evolution and respiration decreased with increase in As (III) concentration and attained its minimal level at 40 ppm of As (III). Therefore, this study highlighted arsenite regimes efficiently correlated with behavioral changes in consort with strain.


Assuntos
Anabaena , Arsenitos , Anabaena/efeitos dos fármacos , Anabaena/metabolismo , Arsenitos/farmacologia , Proteínas de Bactérias/metabolismo , Poluentes Ambientais/farmacologia , Ativação Enzimática/efeitos dos fármacos , Nitrogênio/metabolismo , Fixação de Nitrogênio/efeitos dos fármacos , Nitrogenase/metabolismo
9.
Int J Mol Sci ; 22(11)2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34072602

RESUMO

Enzymes play a fundamental role in many biological processes. We present a theoretical approach to investigate the catalytic power of the haloalkane dehalogenase reaction with 1,2-dichloroethane. By removing the three main active-site residues one by one from haloalkane dehalogenase, we found two reactive descriptors: one descriptor is the distance difference between the breaking bond and the forming bond, and the other is the charge difference between the transition state and the reactant complex. Both descriptors scale linearly with the reactive barriers, with the three-residue case having the smallest barrier and the zero-residue case having the largest. The results demonstrate that, as the number of residues increases, the catalytic power increases. The predicted free energy barriers using the two descriptors of this reaction in water are 23.1 and 24.2 kcal/mol, both larger than the ones with any residues, indicating that the water solvent hinders the reactivity. Both predicted barrier heights agree well with the calculated one at 25.2 kcal/mol using a quantum mechanics and molecular dynamics approach, and also agree well with the experimental result at 26.0 kcal/mol. This study shows that reactive descriptors can also be used to describe and predict the catalytic performance for enzyme catalysis.


Assuntos
Dicloretos de Etileno/química , Dicloretos de Etileno/farmacologia , Hidrolases/química , Hidrolases/metabolismo , Algoritmos , Catálise , Ativação Enzimática/efeitos dos fármacos , Modelos Químicos , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Teoria Quântica , Relação Estrutura-Atividade
10.
Int J Biol Macromol ; 184: 250-258, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34126146

RESUMO

The mitochondrial permeability transition pore (PTP), which drives regulated cell death when Ca2+ concentration suddenly increases in mitochondria, was related to changes in the Ca2+-activated F1FO-ATPase. The effects of the gadolinium cation (Gd3+), widely used for diagnosis and therapy, and reported as PTP blocker, were evaluated on the F1FO-ATPase activated by Mg2+ or Ca2+ and on the PTP. Gd3+ more effectively inhibits the Ca2+-activated F1FO-ATPase than the Mg2+-activated F1FO-ATPase by a mixed-type inhibition on the former and by uncompetitive mechanism on the latter. Most likely Gd3+ binding to F1, is favoured by Ca2+ insertion. The maximal inactivation rates (kinact) of pseudo-first order inactivation are similar either when the F1FO-ATPase is activated by Ca2+ or by Mg2+. The half-maximal inactivator concentrations (KI) are 2.35 ± 0.35 mM and 0.72 ± 0.11 mM, respectively. The potency of a mechanism-based inhibitor (kinact/KI) also highlights a higher inhibition efficiency of Gd3+ on the Ca2+-activated F1FO-ATPase (0.59 ± 0.09 mM-1∙s-1) than on the Mg2+-activated F1FO-ATPase (0.13 ± 0.02 mM-1∙s-1). Consistently, the PTP is desensitized in presence of Gd3+. The Gd3+ inhibition on both the mitochondrial Ca2+-activated F1FO-ATPase and the PTP strengthens the link between the PTP and the F1FO-ATPase when activated by Ca2+ and provides insights on the biological effects of Gd3+.


Assuntos
Inibidores Enzimáticos/farmacologia , Gadolínio/farmacologia , Mitocôndrias/metabolismo , Poro de Transição de Permeabilidade Mitocondrial/farmacologia , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Animais , Cálcio/metabolismo , Cátions , Ativação Enzimática/efeitos dos fármacos , Cinética , Magnésio/metabolismo , Mitocôndrias/efeitos dos fármacos , ATPases Mitocondriais Próton-Translocadoras/química , Modelos Moleculares , Conformação Proteica , Sus scrofa
11.
Food Chem ; 362: 130241, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34118508

RESUMO

Tyrosinase plays an important role in melanin biosynthesis and enzymatic browning of fresh-cut fruit and vegetables. To discover potent tyrosinase inhibitors and antibrowning agents, a series of novel kojic acid derivatives containing bioactive heterocycle moiety (4a-4l) were designed and synthesized. Thereinto, 4d displayed the most potent tyrosinase inhibitory activity with IC50 of 3.23 ± 0.26 µM and behaved as a competitive inhibitor with a Ki of 1.96 µM, compared to kojic acid (IC50 = 32.23 ± 2.01 µM). Besides, copper-chelating assay, fluorescence spectrum quenching experiment, ANS-binding fluorescence quenching analysis, and molecular modeling studies indicated that 4d may inhibit tyrosinase activity by chelating with copper ions in the active site of tyrosinase. Furthermore, 4d exhibited low cytotoxic activity and significant antibrowning effects.This study suggests that these compounds may serve as lead molecules for developing novel tyrosinase inhibitors and antibrowning agents.


Assuntos
Aditivos Alimentares/química , Modelos Moleculares , Monofenol Mono-Oxigenase/metabolismo , Pironas/química , Pironas/farmacologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia
12.
Nat Commun ; 12(1): 3444, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103528

RESUMO

AKT is involved in a number of key cellular processes including cell proliferation, apoptosis and metabolism. Hyperactivation of AKT is associated with many pathological conditions, particularly cancers. Emerging evidence indicates that arginine methylation is involved in modulating AKT signaling pathway. However, whether and how arginine methylation directly regulates AKT kinase activity remain unknown. Here we report that protein arginine methyltransferase 5 (PRMT5), but not other PRMTs, promotes AKT activation by catalyzing symmetric dimethylation of AKT1 at arginine 391 (R391). Mechanistically, AKT1-R391 methylation cooperates with phosphatidylinositol 3,4,5 trisphosphate (PIP3) to relieve the pleckstrin homology (PH)-in conformation, leading to AKT1 membrane translocation and subsequent activation by phosphoinositide-dependent kinase-1 (PDK1) and the mechanistic target of rapamycin complex 2 (mTORC2). As a result, deficiency in AKT1-R391 methylation significantly suppresses AKT1 kinase activity and tumorigenesis. Lastly, we show that PRMT5 inhibitor synergizes with AKT inhibitor or chemotherapeutic drugs to enhance cell death. Altogether, our study suggests that R391 methylation is an important step for AKT activation and its oncogenic function.


Assuntos
Arginina/metabolismo , Carcinogênese/metabolismo , Carcinogênese/patologia , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Antineoplásicos/farmacologia , Biocatálise/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Metilação/efeitos dos fármacos , Camundongos Nus , Mutação/genética , Ligação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteína-Arginina N-Metiltransferases/deficiência , Proteínas Proto-Oncogênicas c-akt/química , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismo , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
Int J Mol Sci ; 22(10)2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-34063504

RESUMO

Protein kinase C (PKC) activation induces cellular reprogramming and differentiation in various cell models. Although many effectors of PKC physiological actions have been elucidated, the molecular mechanisms regulating oligodendrocyte differentiation after PKC activation are still unclear. Here, we applied a liquid chromatography-mass spectrometry (LC-MS/MS) approach to provide a comprehensive analysis of the proteome expression changes in the MO3.13 oligodendroglial cell line after PKC activation. Our findings suggest that multiple networks that communicate and coordinate with each other may finally determine the fate of MO3.13 cells, thus identifying a modular and functional biological structure. In this work, we provide a detailed description of these networks and their participating components and interactions. Such assembly allows perturbing each module, thus describing its physiological significance in the differentiation program. We applied this approach by targeting the Rho-associated protein kinase (ROCK) in PKC-activated cells. Overall, our findings provide a resource for elucidating the PKC-mediated network modules that contribute to a more robust knowledge of the molecular dynamics leading to this cell fate transition.


Assuntos
Diferenciação Celular/fisiologia , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Proteína Quinase C/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Espectrometria de Massas/métodos , Oligodendroglia/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Quinases Associadas a rho/metabolismo
14.
Nat Commun ; 12(1): 3483, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108481

RESUMO

The hexameric AAA-ATPase Drg1 is a key factor in eukaryotic ribosome biogenesis and initiates cytoplasmic maturation of the large ribosomal subunit by releasing the shuttling maturation factor Rlp24. Drg1 monomers contain two AAA-domains (D1 and D2) that act in a concerted manner. Rlp24 release is inhibited by the drug diazaborine which blocks ATP hydrolysis in D2. The mode of inhibition was unknown. Here we show the first cryo-EM structure of Drg1 revealing the inhibitory mechanism. Diazaborine forms a covalent bond to the 2'-OH of the nucleotide in D2, explaining its specificity for this site. As a consequence, the D2 domain is locked in a rigid, inactive state, stalling the whole Drg1 hexamer. Resistance mechanisms identified include abolished drug binding and altered positioning of the nucleotide. Our results suggest nucleotide-modifying compounds as potential novel inhibitors for AAA-ATPases.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/química , Adenosina Trifosfatases/química , Compostos de Boro/química , Proteínas de Saccharomyces cerevisiae/química , Domínio AAA , ATPases Associadas a Diversas Atividades Celulares/antagonistas & inibidores , ATPases Associadas a Diversas Atividades Celulares/genética , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Adenosina Trifosfatases/antagonistas & inibidores , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Sítios de Ligação , Compostos de Boro/farmacologia , Resistência a Medicamentos/genética , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/genética , Mutação , Nucleotídeos/química , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
15.
Life Sci ; 280: 119694, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34102192

RESUMO

Cancer is a leading cause of death globally. Cancer cell transformation is the result of intricate crosstalk between intracellular components and proteins. A characteristic feature of cancer cells is the ability to reprogram their metabolic pathways to ensure their infinite proliferative potential. Pyruvate kinase muscle isoform 2 (PKM2) is a glycolytic enzyme that plays crucial roles in cancer, apart from carrying out its metabolic roles. PKM2 is involved in all the major events associated with cancer growth. Modulation of PKM2 activity (dimer inhibition or tetramer activation) has been successful in controlling cancer. However, recent studies provide contrary evidences regarding the oncogenic functions of PKM2. Moreover, several studies have highlighted the cancerous roles of PKM1 isoform in certain contexts. The present review aims at providing the current updates regarding PKM2 targeting in cancer. Further, the review discusses the contradictory results that suggest that both the isoforms of PKM can lead to cancer growth. In conclusion, the review emphasizes revisiting the approaches to target cancer metabolism through PKM to find novel and effective targets for anticancer therapy.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo , Neoplasias/metabolismo , Hormônios Tireóideos/metabolismo , Animais , Antineoplásicos/farmacologia , Carcinogênese/efeitos dos fármacos , Carcinogênese/metabolismo , Carcinogênese/patologia , Proteínas de Transporte/agonistas , Proteínas de Transporte/análise , Proteínas de Transporte/antagonistas & inibidores , Descoberta de Drogas , Ativação Enzimática/efeitos dos fármacos , Ativadores de Enzimas/farmacologia , Inibidores Enzimáticos/farmacologia , Humanos , Proteínas de Membrana/agonistas , Proteínas de Membrana/análise , Proteínas de Membrana/antagonistas & inibidores , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Hormônios Tireóideos/agonistas , Hormônios Tireóideos/análise
16.
Nat Commun ; 12(1): 3763, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34145245

RESUMO

The glucagon-like peptide-1 (GLP-1) receptor is a validated drug target for metabolic disorders. Ago-allosteric modulators are capable of acting both as agonists on their own and as efficacy enhancers of orthosteric ligands. However, the molecular details of ago-allosterism remain elusive. Here, we report three cryo-electron microscopy structures of GLP-1R bound to (i) compound 2 (an ago-allosteric modulator); (ii) compound 2 and GLP-1; and (iii) compound 2 and LY3502970 (a small molecule agonist), all in complex with heterotrimeric Gs. The structures reveal that compound 2 is covalently bonded to C347 at the cytoplasmic end of TM6 and triggers its outward movement in cooperation with the ECD whose N terminus penetrates into the GLP-1 binding site. This allows compound 2 to execute positive allosteric modulation through enhancement of both agonist binding and G protein coupling. Our findings offer insights into the structural basis of ago-allosterism at GLP-1R and may aid the design of better therapeutics.


Assuntos
Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Animais , Sítios de Ligação/fisiologia , Células CHO , Linhagem Celular , Cricetulus , Microscopia Crioeletrônica , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ativação Enzimática/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Peptídeos Semelhantes ao Glucagon/farmacologia , Células HEK293 , Humanos , Simulação de Dinâmica Molecular , Conformação Proteica , Células Sf9 , Spodoptera
17.
J Chromatogr A ; 1651: 462305, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34147833

RESUMO

Indoleamine 2,3-dioxygenase 1 (IDO1) has been shown to play an important role in the immune escape process of tumors, and therefore is considered as a promising target for tumor immunotherapy. In this study, off-line and on-line capillary electrophoresis methods were developed for IDO1 inhibitors screening from natural product extracts. The optimized separation conditions of CE were achieved with 32 mM sodium tetraborate (pH 9.22) as background electrolyte, using a separation voltage of 21 kV. The off-line CE method was verified by the determination of enzymatic kinetic parameters and inhibitory mechanisms of two known inhibitors. A partial filling on-line CE method combined with rapid polarity switching was used for rapid screening of IDO1 inhibitors. The whole reaction and separation process was completed within 5 min. The on-line CE screening results showed that six of 18 natural products had inhibitory effect on IDO1, namely Carthamus tinctorius, Schisandra chinensis, Raisin, Coffee, Hawthorn and Radix angelicae sinensis. The results of on-line CE experiments were consistent with the off-line results, which proved the practicability and effectiveness of the method for inhibitors screening.


Assuntos
Técnicas de Química Analítica/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Eletroforese Capilar , Inibidores Enzimáticos/isolamento & purificação , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Produtos Biológicos/química , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Humanos
18.
Sci Immunol ; 6(59)2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-34010142

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic, resulting millions of infections and deaths with few effective interventions available. Here, we demonstrate that SARS-CoV-2 evades interferon (IFN) activation in respiratory epithelial cells, resulting in a delayed response in bystander cells. Since pretreatment with IFNs can block viral infection, we reasoned that pharmacological activation of innate immune pathways could control SARS-CoV-2 infection. To identify potent antiviral innate immune agonists, we screened a panel of 75 microbial ligands that activate diverse signaling pathways and identified cyclic dinucleotides (CDNs), canonical STING agonists, as antiviral. Since CDNs have poor bioavailability, we tested the small molecule STING agonist diABZI, and found that it potently inhibits SARS-CoV-2 infection of diverse strains including variants of concern (B.1.351) by transiently stimulating IFN signaling. Importantly, diABZI restricts viral replication in primary human bronchial epithelial cells and in mice in vivo. Our study provides evidence that activation of STING may represent a promising therapeutic strategy to control SARS-CoV-2.


Assuntos
Antivirais/farmacologia , Benzimidazóis/farmacologia , COVID-19/prevenção & controle , Interferons/imunologia , Proteínas de Membrana/agonistas , Animais , Linhagem Celular , Chlorocebus aethiops , Ativação Enzimática/efeitos dos fármacos , Células Epiteliais/virologia , Humanos , Evasão da Resposta Imune/imunologia , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , SARS-CoV-2/crescimento & desenvolvimento , SARS-CoV-2/imunologia , Células Vero , Replicação Viral/efeitos dos fármacos
19.
Front Immunol ; 12: 581799, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33953705

RESUMO

Forkhead box O 3 (FOXO3) is a transcription factor involved in cell metabolism, inflammation and longevity. Here, we investigated if metformin can activate FOXO3 in human immune cells and affects the subsequent level of reactive oxygen/nitrogen species (ROS/RNS) in immune cells. AMP-activated protein kinase (AMPK) and FOXO3 activation were investigated by immunoblot or flow cytometry (FC) analysis, respectively. FOXO3 target gene expression was quantified by real-time PCR. ROS/RNS measurement using dichlorodihydrofluorescein diacetate (DCFH-DA) dye was investigated by FC. The role of the FOXO3 single nucleotide polymorphisms (SNPs) rs12212067, rs2802292 and rs12206094 on ROS/RNS production was studied using allelic discrimination PCR. Metformin induced activation of AMPK (pT172) and FOXO3 (pS413). ROS/RNS level was reduced in immune cells after metformin stimulation accompanied by induction of the FOXO3 targets mitochondrial superoxide dismutase and cytochrome c. Studies in Foxo3 deficient (Foxo3-/- ) mouse splenocytes confirmed that metformin mediates its effects via Foxo3 as it attenuates ROS/RNS in myeloid cells of wildtype (WT) but not of Foxo3-/- mice. Our results suggest that FOXO3 can be activated by metformin leading to reduced ROS/RNS level in immune cells. This may add to the beneficial clinical effects of metformin observed in large cohort studies on longevity, cardiovascular and cancer risk.


Assuntos
Proteína Forkhead Box O3/metabolismo , Sistema Imunitário/efeitos dos fármacos , Metformina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Proteína Forkhead Box O3/genética , Expressão Gênica/efeitos dos fármacos , Humanos , Hipoglicemiantes/farmacologia , Sistema Imunitário/citologia , Sistema Imunitário/metabolismo , Camundongos Knockout , Polimorfismo de Nucleotídeo Único , Baço/citologia , Baço/efeitos dos fármacos , Baço/metabolismo
20.
Int J Mol Sci ; 22(9)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33946730

RESUMO

Granulosa cell tumors (GCT) constitute only ~5% of ovarian neoplasms yet have significant consequences, as up to 80% of women with recurrent GCT will die of the disease. This study investigated the effectiveness of procaspase-activating compound 1 (PAC-1), an activator of procaspase-3, in treating adult GCT (AGCT) in combination with selected apoptosis-inducing agents. Sensitivity of the AGCT cell line KGN to these drugs, alone or in combination with PAC-1, was tested using a viability assay. Our results show a wide range in cytotoxic activity among the agents tested. Synergy with PAC-1 was most pronounced, both empirically and by mathematical modelling, when combined with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). This combination showed rapid kinetics of apoptosis induction as determined by caspase-3 activity, and strongly synergistic killing of both KGN as well as patient samples of primary and recurrent AGCT. We have demonstrated that the novel combination of two pro-apoptotic agents, TRAIL and PAC-1, significantly amplified the induction of apoptosis in AGCT cells, warranting further investigation of this combination as a potential therapy for AGCT.


Assuntos
Tumor de Células da Granulosa/tratamento farmacológico , Hidrazonas/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Piperazinas/administração & dosagem , Ligante Indutor de Apoptose Relacionado a TNF/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptose/efeitos dos fármacos , Benzoquinonas/administração & dosagem , Carboplatina/administração & dosagem , Caspase 3/metabolismo , Linhagem Celular Tumoral , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Ativação Enzimática/efeitos dos fármacos , Feminino , Tumor de Células da Granulosa/enzimologia , Tumor de Células da Granulosa/patologia , Humanos , Técnicas In Vitro , Conceitos Matemáticos , Modelos Biológicos , Neoplasias Ovarianas/enzimologia , Neoplasias Ovarianas/patologia
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