RESUMEN
AMP-activated protein kinase (AMPK) and mechanistic target of rapamycin complex 1 (mTORC1) are metabolic kinases that co-ordinate nutrient supply with cell growth. AMPK negatively regulates mTORC1, and mTORC1 reciprocally phosphorylates S345/7 in both AMPK α-isoforms. We report that genetic or torin1-induced loss of α2-S345 phosphorylation relieves suppression of AMPK signaling; however, the regulatory effect does not translate to α1-S347 in HEK293T or MEF cells. Dephosphorylation of α2-S345, but not α1-S347, transiently targets AMPK to lysosomes, a cellular site for activation by LKB1. By mass spectrometry, we find that α2-S345 is basally phosphorylated at 2.5-fold higher stoichiometry than α1-S347 in HEK293T cells and, unlike α1, phosphorylation is partially retained after prolonged mTORC1 inhibition. Loss of α2-S345 phosphorylation in endogenous AMPK fails to sustain growth of MEFs under amino acid starvation conditions. These findings uncover an α2-specific mechanism by which AMPK can be activated at lysosomes in the absence of changes in cellular energy.
Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Lisosomas/metabolismo , Quinasas de la Proteína-Quinasa Activada por el AMP/metabolismo , Secuencia de Aminoácidos , Animales , Activación Enzimática , Femenino , Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/metabolismo , Células HEK293 , Células HeLa , Humanos , Isoenzimas/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Ratones Endogámicos C57BL , Fosforilación , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismoRESUMEN
Diabetes mellitus is a global threat affecting millions of people of different age groups. In recent years, the development of naturally derived anti-diabetic agents has gained popularity. Okra is a common vegetable containing important bioactive components such as abscisic acid (ABA). ABA, a phytohormone, has been shown to elicit potent anti-diabetic effects in mouse models. Keeping its anti-diabetic potential in mind, in silico study was performed to explore its role in inhibiting proteins relevant to diabetes mellitus- 11ß-hydroxysteroid dehydrogenase (11ß-HSD1), aldose reductase, glucokinase, glutamine-fructose-6-phosphate amidotransferase (GFAT), peroxisome proliferator-activated receptor-gamma (PPAR-gamma), and Sirtuin family of NAD(+)-dependent protein deacetylases 6 (SIRT6). A comparative study of the ABA-protein docked complex with already known inhibitors of these proteins relevant to diabetes was compared to explore the inhibitory potential. Calculation of molecular binding energy (ΔG), inhibition constant (pKi), and prediction of pharmacokinetics and pharmacodynamics properties were performed. The molecular docking investigation of ABA with 11-HSD1, GFAT, PPAR-gamma, and SIRT6 revealed considerably low binding energy (ΔG from -8.1 to -7.3 Kcal/mol) and predicted inhibition constant (pKi from 6.01 to 5.21 µM). The ADMET study revealed that ABA is a promising drug candidate without any hazardous effect following all current drug-likeness guidelines such as Lipinski, Ghose, Veber, Egan, and Muegge.
Asunto(s)
Abelmoschus/química , Ácido Abscísico/farmacología , Diabetes Mellitus/metabolismo , Hipoglucemiantes/farmacología , Proteínas/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/antagonistas & inhibidores , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/química , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , Ácido Abscísico/química , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacocinética , Aldehído Reductasa/química , Aldehído Reductasa/metabolismo , Simulación por Computador , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Glucoquinasa/química , Glucoquinasa/metabolismo , Glutamina/metabolismo , Glutamina-Fructosa-6-Fosfato Transaminasa (Isomerizadora)/metabolismo , Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/metabolismo , Humanos , Hipoglucemiantes/química , Simulación del Acoplamiento Molecular , PPAR gamma/química , PPAR gamma/metabolismo , Proteínas/química , Sirtuinas/química , Sirtuinas/metabolismoRESUMEN
Malaria is one of the most dangerous infectious diseases. Because the causative Plasmodium parasites have developed resistances against virtually all established antimalarial drugs, novel antiplasmodial agents are required. In order to target plasmodial kinases, novel N-unsubstituted bisindolylcyclobutenediones were designed as analogs to the kinase inhibitory bisindolylmaleimides. Molecular docking experiments produced favorable poses of the unsubstituted bisindolylcyclobutenedione in the ATP binding pocket of various plasmodial protein kinases. The synthesis of the title compounds was accomplished by sequential Friedel-Crafts acylation procedures. In vitro screening of the new compounds against transgenic NF54-luc P. falciparum parasites revealed a set of derivatives with submicromolar activity, of which some displayed a reasonable selectivity profile against a human cell line. Although the molecular docking studies suggested the plasmodial protein kinase PfGSK-3 as the putative biological target, the title compounds failed to inhibit the isolated enzyme in vitro. As selective submicromolar antiplasmodial agents, the N-unsubstituted bisindolylcyclobutenediones are promising starting structures in the search for antimalarial drugs, albeit for a rational development, the biological target addressed by these compounds has yet to be identified.
Asunto(s)
Antimaláricos/síntesis química , Antimaláricos/farmacología , Indoles/síntesis química , Indoles/farmacología , Adenosina Trifosfato/metabolismo , Antimaláricos/química , Antimaláricos/metabolismo , Sitios de Unión , Técnicas de Química Sintética , Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/metabolismo , Indoles/química , Indoles/metabolismo , Simulación del Acoplamiento Molecular , Pruebas de Sensibilidad Parasitaria , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/enzimología , Conformación Proteica , Relación Estructura-ActividadRESUMEN
Recently neuronal insulin resistance was suggested playing a role in Alzheimer's disease. Streptozotocin (STZ) is commonly used to induce impairment in insulin metabolism. In our previous work on undifferentiated SH-SY5Y cells the compound exerted cytotoxicity without altering insulin sensitivity. Nevertheless, differentiation of the cells to a more mature neuron-like phenotype may considerably affect the significance of insulin signaling and its sensitivity to STZ. We aimed at studying the influence of STZ treatment on insulin signaling in SH-SY5Y cells differentiated by retinoic acid (RA). Cytotoxicity of STZ or low serum (LS) condition and protective effect of insulin were compared in RA differentiated SH-SY5Y cells. The effect of insulin and an incretin analogue, exendin-4 on insulin signaling was also examined by assessing glycogen synthase kinase-3 (GSK-3) phosphorylation. STZ was found less cytotoxic in the differentiated cells compared to our previous results in undifferentiated SH-SY5Y cells. The cytoprotective concentration of insulin was similar in the STZ and LS groups. However, the right-shifted concentration-response curve of insulin induced GSK-3 phosphorylation in STZ-treated differentiated cells is suggestive of the development of insulin resistance that was further confirmed by the insulin potentiating effect of exendin-4. Differentiation reduced the sensitivity of SH-SY5Y cells for the non-specific cytotoxicity of STZ and enhanced the relative significance of development of insulin resistance. The differentiated cells thus serve as a better model for studying the role of insulin signaling in neuronal survival. However, direct cytotoxicity of STZ also contributes to the cell death.
Asunto(s)
Diferenciación Celular/fisiología , Resistencia a la Insulina/fisiología , Insulina/farmacología , Estreptozocina/toxicidad , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Exenatida/farmacología , Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/metabolismo , Humanos , Fosforilación/efectos de los fármacos , Fosforilación/fisiología , Transducción de Señal/efectos de los fármacos , Tretinoina/farmacologíaRESUMEN
In-house 1,5-oxaza spiroquinone 1, with spiro[5.5]undeca ring system, was announced as an unprecedented anti-inflammatory scaffold through chemistry-oriented synthesis (ChOS), a chemocentric approach. Herein, we studied how to best position the spiro[5.5]undeca ring system in kinase inhibitor space. Notably, late-stage modification of the scaffold 1 into compounds 2a-r enhanced kinase-likeness of the scaffold 1. The improvement could be depicted with (1) selectivity with target shift (from JNK-1 into GSK-3) and (2) potency (> 20-fold). In addition, ATP independent IC50 of compound 2j suggested a unique binding mode of this scaffold between ATP site and substrate site, which was explained by docking based optimal site selection and molecular dynamic simulations of the optimal binding site. Despite the shift of kinase profiling, the anti-inflammatory activity of compounds 2a-r could be retained in hyperactivated microglial cells.
Asunto(s)
Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/metabolismo , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/metabolismo , Androstadienos/química , Androstadienos/metabolismo , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Estructura Molecular , Estructura Secundaria de Proteína , Relación Estructura-ActividadRESUMEN
The serine/threonine kinase, GSK-3, is a promising drug discovery target for treating multiple pathological disorders. Most GSK-3 inhibitors that were developed function as ATP competitive inhibitors, with typical limitations in specificity, safety and drug-induced resistance. In contrast, substrate competitive inhibitors (SCIs), are considered highly selective, and more suitable for clinical practice. The development of SCIs has been largely neglected in the past because the ambiguous, undefined nature of the substrate-binding site makes them difficult to design. In this study, we used our previously described structural models of GSK-3 bound to SCI peptides, to design a pharmacophore model and to virtually screen the "drug-like" Zinc database (~6.3 million compounds). We identified leading hits that interact with critical binding elements in the GSK-3 substrate binding site and are chemically distinct from known GSK-3 inhibitors. Accordingly, novel GSK-3 SCI compounds were designed and synthesized with IC50 values of~1-4 µM. Biological activity of the SCI compound was confirmed in cells and in primary neurons that showed increased ß-catenin levels and reduced tau phosphorylation in response to compound treatment. We have generated a new type of small molecule GSK-3 inhibitors and propose to use this strategy to further develop SCIs for other protein kinases.
Asunto(s)
Diseño de Fármacos , Descubrimiento de Drogas/métodos , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Bibliotecas de Moléculas Pequeñas/farmacología , Animales , Sitios de Unión , Línea Celular Tumoral , Células Cultivadas , Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/metabolismo , Humanos , Cinética , Ratones Endogámicos C57BL , Simulación del Acoplamiento Molecular , Estructura Molecular , Unión Proteica , Dominios Proteicos , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/metabolismo , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/metabolismo , Especificidad por SustratoRESUMEN
Dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A) is a protein kinase with diverse functions in cell regulation. Abnormal expression and activity of DYRK1A contribute to numerous human malignancies, Down syndrome, and Alzheimer's disease. Notably, DYRK1A has been proposed as a potential therapeutic target for the treatment of diabetes because of its key role in pancreatic ß-cell proliferation. Consequently, DYRK1A is an attractive drug target for a variety of diseases. Here, we report the identification of several DYRK1A inhibitors using our in-house topological water network-based approach. All inhibitors were further verified by in vitro assay.
Asunto(s)
Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3/química , Simulación de Dinámica Molecular , Inhibidores de Proteínas Quinasas/química , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/química , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/química , Química Computacional , Humanos , Ligandos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , Bibliotecas de Moléculas Pequeñas , Quinasas DyrKRESUMEN
GSK3 has been implicated for years in the regulation of inflammation and addressed in a plethora of scientific reports using a variety of experimental (disease) models and approaches. However, the specific role of GSK3 in the inflammatory process is still not fully understood and controversially discussed. Following a detailed overview of structure, function, and various regulatory levels, this review focusses on the immunoregulatory functions of GSK3, including the current knowledge obtained from animal models. Its impact on pro-inflammatory cytokine/chemokine profiles, bacterial/viral infections, and the modulation of associated pro-inflammatory transcriptional and signaling pathways is discussed. Moreover, GSK3 contributes to the resolution of inflammation on multiple levels, e.g., via the regulation of pro-resolving mediators, the clearance of apoptotic immune cells, and tissue repair processes. The influence of GSK3 on the development of different forms of stimulation tolerance is also addressed. Collectively, the role of GSK3 as a kinase balancing the initiation/perpetuation and the amelioration/resolution of inflammation is highlighted.
Asunto(s)
Glucógeno Sintasa Quinasa 3/metabolismo , Inflamación/enzimología , Inflamación/patología , Animales , Apoptosis/efectos de los fármacos , Ensayos Clínicos como Asunto , Modelos Animales de Enfermedad , Glucógeno Sintasa Quinasa 3/química , Humanos , Transducción de Señal/efectos de los fármacosRESUMEN
It has demonstrated that glycogen synthase kinase 3ß (GSK3ß) is related to Alzheimer's disease (AD). On the basis of the world largest traditional Chinese medicine (TCM) database, a network-pharmacology-based approach was utilized to investigate TCM candidates that can dock well with multiple targets. Support vector machine (SVM) and multiple linear regression (MLR) methods were utilized to obtain predicted models. In particular, the deep learning method and the random forest (RF) algorithm were adopted. We achieved R2 values of 0.927 on the training set and 0.862 on the test set with deep learning and 0.869 on the training set and 0.890 on the test set with RF. Besides, comparative molecular similarity indices analysis (CoMSIA) was performed to get a predicted model. All of the training models achieved good results on the test set. The stability of GSK3ß protein-ligand complexes was evaluated using 100 ns of MD simulation. Methyl 3- O-feruloylquinate and cynanogenin A induced both more compactness to the GSK3ß complex and stable conditions at all simulation times, and the GSK3ß complex also had no substantial fluctuations after a simulation time of 5 ns. For TCM molecules, we used the trained models to calculate predicted bioactivity values, and the optimum TCM candidates were obtained by ranking the predicted values. The results showed that methyl 3- O-feruloylquinate contained in Phellodendron amurense and cynanogenin A contained in Cynanchum atratum are capable of forming stable interactions with GSK3ß.
Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Biología Computacional/métodos , Aprendizaje Profundo , Medicina Tradicional China , Bases de Datos Farmacéuticas , Composición de Medicamentos , Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/metabolismo , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Conformación Proteica , Mapas de Interacción de Proteínas , Relación Estructura-Actividad Cuantitativa , Máquina de Vectores de SoporteRESUMEN
Glycogen synthase kinase-3 (GSK-3), a serine/threonine kinase is an archetypal multifunctional moonlighting protein involved in diverse cellular processes including metabolism, insulin signaling, proliferation, differentiation, apoptosis, neuronal function and embryonic development. The two known isoforms, GSK-3α and GSK-3ß that undergo activation/inactivation by post-translational, site-specific phosphorylation incorporate a vast number of substrates in their repertoire. Dysregulation of GSK-3 has been linked to diverse disease entities including cancer. The role of GSK-3 in cancer is paradoxical and enigmatic. The enzyme functions as a tumour promoter or suppressor based on the context, cell type and phosphorylation status. GSK-3 is the central hub that orchestrates signals from the Wnt/ß-catenin, PI3K/PTEN/Akt/mTOR, Ras/Raf/MEK/ERK, hedgehog, Notch and TP53 pathways to elicit regulatory influences on cancer initiation, epithelial-mesenchymal transition, and resistance to therapy. As a direct target of several microRNAs, GSK-3 influences hallmark attributes of cancer, cancer stemness and treatment resistance. There is overwhelming evidence to indicate that GSK-3 is aberrantly regulated in different cancer types. Consequently, GSK-3 has emerged as a potential therapeutic target in cancer. A plethora of natural and synthetic GSK-3 modulators have been discovered and the number of patents published for GSK-3 inhibitors has also been steadily increasing in recent years. This review focuses on the intricate interactions between GSK-3 and oncogenic signalling circuits as well as the feasibility of targeting GSK-3 for the treatment of cancer.
Asunto(s)
Glucógeno Sintasa Quinasas/genética , Glucógeno Sintasa Quinasas/metabolismo , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antineoplásicos Fitogénicos , Biomarcadores de Tumor , Susceptibilidad a Enfermedades , Activación Enzimática , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasas/antagonistas & inhibidores , Glucógeno Sintasa Quinasas/química , Humanos , Isoenzimas , MicroARNs/genética , Terapia Molecular Dirigida , Neoplasias/tratamiento farmacológico , Neoplasias/etiología , Neoplasias/metabolismo , Neoplasias/patología , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Interferencia de ARN , Transducción de Señal/efectos de los fármacos , Relación Estructura-ActividadRESUMEN
BRZ-INSENSITIVE-LONG HYPOCOTYL 1 (BIL1)/BRASSINAZOLE-RESISTANT 1 (BZR1) is a master transcription factor of brassinosteroid (BR) signalling. The varieties of nucleobase recognition of the NN-BRRE-core motif (NNCGTG), one of variant G-box motifs, distinguish BIL1/BZR1 from basic helix-loop-helix transcription factors, underlying the specific regulation of BR-responsive genes. Here, we show the non-canonical bHLH dimer formation of BIL1/BZR1 to optimize the interaction network with DNA and the orientation of a key residue for NN-BRRE-core motif recognition.
Asunto(s)
Proteínas de Arabidopsis/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Brasinoesteroides/metabolismo , Glucógeno Sintasa Quinasa 3/metabolismo , Proteínas Nucleares/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/química , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , ADN de Plantas/metabolismo , Proteínas de Unión al ADN , Dimerización , Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/genética , Proteínas Nucleares/química , Proteínas Nucleares/genética , Alineación de SecuenciaRESUMEN
Neural crest migration is critical to its physiological function. Mechanisms controlling mammalian neural crest migration are comparatively unknown, due to difficulties accessing this cell population in vivo. Here we report requirements of glycogen synthase kinase 3 (GSK3) in regulating the neural crest in Xenopus and mouse models. We demonstrate that GSK3 is tyrosine phosphorylated (pY) in mouse neural crest cells and that loss of GSK3 leads to increased pFAK and misregulation of Rac1 and lamellipodin, key regulators of cell migration. Genetic reduction of GSK3 results in failure of migration. We find that pY-GSK3 phosphorylation depends on anaplastic lymphoma kinase (ALK), a protein associated with neuroblastoma. Consistent with this, neuroblastoma cells with increased ALK activity express high levels of pY-GSK3, and blockade of GSK3 or ALK can affect migration of these cells. Altogether, this work identifies a role for GSK3 in cell migration during neural crest development and cancer.
Asunto(s)
Glucógeno Sintasa Quinasa 3/metabolismo , Cresta Neural/citología , Cresta Neural/enzimología , Proteínas de Xenopus/química , Quinasa de Linfoma Anaplásico/antagonistas & inhibidores , Quinasa de Linfoma Anaplásico/metabolismo , Animales , Línea Celular Tumoral , Linaje de la Célula , Movimiento Celular/fisiología , Femenino , Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/deficiencia , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3 beta/deficiencia , Glucógeno Sintasa Quinasa 3 beta/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Humanos , Ratones , Ratones Noqueados , Cresta Neural/embriología , Neuroblastoma/enzimología , Fosforilación , Embarazo , Proteínas de Xenopus/metabolismo , Xenopus laevis/embriología , Xenopus laevis/metabolismoRESUMEN
Glycogen synthase kinase 3 (GSK3), a key regulatory kinase in the wingless-type MMTV integration site family (WNT) pathway, is a therapeutic target of interest in many diseases. Although dual GSK3α/ß inhibitors have entered clinical trials, none has successfully translated to clinical application. Mechanism-based toxicities, driven in part by the inhibition of both GSK3 paralogs and subsequent ß-catenin stabilization, are a concern in the translation of this target class because mutations and overexpression of ß-catenin are associated with many cancers. Knockdown of GSK3α or GSK3ß individually does not increase ß-catenin and offers a conceptual resolution to targeting GSK3: paralog-selective inhibition. However, inadequate chemical tools exist. The design of selective adenosine triphosphate (ATP)-competitive inhibitors poses a drug discovery challenge due to the high homology (95% identity and 100% similarity) in this binding domain. Taking advantage of an Asp133âGlu196 "switch" in their kinase hinge, we present a rational design strategy toward the discovery of paralog-selective GSK3 inhibitors. These GSK3α- and GSK3ß-selective inhibitors provide insights into GSK3 targeting in acute myeloid leukemia (AML), where GSK3α was identified as a therapeutic target using genetic approaches. The GSK3α-selective compound BRD0705 inhibits kinase function and does not stabilize ß-catenin, mitigating potential neoplastic concerns. BRD0705 induces myeloid differentiation and impairs colony formation in AML cells, with no apparent effect on normal hematopoietic cells. Moreover, BRD0705 impairs leukemia initiation and prolongs survival in AML mouse models. These studies demonstrate feasibility of paralog-selective GSK3α inhibition, offering a promising therapeutic approach in AML.
Asunto(s)
Inhibidores Enzimáticos/uso terapéutico , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Leucemia Mieloide Aguda/tratamiento farmacológico , Dipéptidos/química , Dipéptidos/metabolismo , Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/metabolismo , Humanos , Mutagénesis Sitio-Dirigida , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Células U937 , beta Catenina/genética , beta Catenina/metabolismoRESUMEN
Glycogen synthase kinase 3 (GSK3) is a critical regulator of diverse cellular functions involved in the maintenance of structure and function. Enzymatic activity of GSK3 is inhibited by N-terminal serine phosphorylation. However, alternate post-translational mechanism(s) responsible for GSK3 inactivation are not characterized. Here, we report that GSK3α and GSK3ß are acetylated at Lys246 and Lys183, respectively. Molecular modeling and/or molecular dynamics simulations indicate that acetylation of GSK3 isoforms would hinder both the adenosine binding and prevent stable interactions of the negatively charged phosphates. We found that SIRT2 deacetylates GSK3ß, and thus enhances its binding to ATP. Interestingly, the reduced activity of GSK3ß is associated with lysine acetylation, but not with phosphorylation at Ser9 in hearts of SIRT2-deficient mice. Moreover, GSK3 is required for the anti-hypertrophic function of SIRT2 in cardiomyocytes. Overall, our study identified lysine acetylation as a novel post-translational modification regulating GSK3 activity.
Asunto(s)
Glucógeno Sintasa Quinasa 3/metabolismo , Isoformas de Proteínas/metabolismo , Procesamiento Proteico-Postraduccional , Sirtuina 2/metabolismo , Animales , Línea Celular , Glucógeno Sintasa Quinasa 3/química , Humanos , Ratones , Ratones Noqueados , Modelos Moleculares , Simulación de Dinámica Molecular , FosforilaciónRESUMEN
In the present study, the changes that occur in rat liver tissue as a result of the use of grape seed extract (GSE) and low level laser therapy (LLLT) in intraoral wound (IW) healing are analyzed using biochemical parameters. Diode laser application groups received 8 J/cm2 dose LLLT once a day for 4 days (810 nm wavelength, continuous mode, 0.25 W, 9 s). As a result of the biological parameter analysis, it was determined that the oxidative damage caused by the IWs and recovery period on 7th and 14th days could be substantially removed with GSE applications that have antioxidant capacity especially in rat liver tissue. In addition, the active compound of grape seed, catechin is studied in the active site of glycogen synthase kinase 3 (GSK3) target using molecular modeling approaches. Post-processing molecular dynamics (MD) results for catechin is compared with a standard GSK3 inhibitor. MD simulations assisted for better understanding of inhibition mechanism and the crucial amino acids contributing in the ligand binding. These results along with a through free energy analysis of ligands using sophisticated simulations methods are quite striking and it suggests a greater future role for simulation in deciphering complex patterns of molecular mechanism in combination with methods for understanding drug-receptor interactions.
Asunto(s)
Antioxidantes/administración & dosificación , Extracto de Semillas de Uva/administración & dosificación , Terapia por Láser , Cicatrización de Heridas/efectos de los fármacos , Administración Oral , Animales , Antioxidantes/química , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3/química , Extracto de Semillas de Uva/química , Humanos , Hígado/efectos de los fármacos , Terapia por Luz de Baja Intensidad , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/efectos de la radiación , Ratas , Cicatrización de Heridas/efectos de la radiaciónRESUMEN
To grow, eukaryotic cells must expand by inserting glycerolipids, sphingolipids, sterols, and proteins into their plasma membrane, and maintain the proper levels and bilayer distribution. A fungal cell must coordinate growth with enlargement of its cell wall. In Saccharomyces cerevisiae, a plasma membrane-localized protein kinase complex, Target of Rapamicin (TOR) complex-2 (TORC2) (mammalian ortholog is mTORC2), serves as a sensor and masterregulator of these plasma membrane- and cell wall-associated events by directly phosphorylating and thereby stimulating the activity of two types of effector protein kinases: Ypk1 (mammalian ortholog is SGK1), along with a paralog (Ypk2); and, Pkc1 (mammalian ortholog is PKN2/PRK2). Ypk1 is a central regulator of pathways and processes required for plasma membrane lipid and protein homeostasis, and requires phosphorylation on its T-loop by eisosome-associated protein kinase Pkh1 (mammalian ortholog is PDK1) and a paralog (Pkh2). For cell survival under various stresses, Ypk1 function requires TORC2-mediated phosphorylation at multiple sites near its C terminus. Pkc1 controls diverse processes, especially cell wall synthesis and integrity. Pkc1 is also regulated by Pkh1- and TORC2-dependent phosphorylation, but, in addition, by interaction with Rho1-GTP and lipids phosphatidylserine (PtdSer) and diacylglycerol (DAG). We also describe here what is currently known about the downstream substrates modulated by Ypk1-mediated and Pkc1-mediated phosphorylation.
Asunto(s)
Redes Reguladoras de Genes , Diana Mecanicista del Complejo 2 de la Rapamicina/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/crecimiento & desarrollo , Membrana Celular/metabolismo , Pared Celular/metabolismo , Regulación Fúngica de la Expresión Génica , Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/metabolismo , Diana Mecanicista del Complejo 2 de la Rapamicina/química , Fosforilación , Unión Proteica , Proteína Quinasa C/metabolismo , Proteínas Quinasas/metabolismo , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Transducción de SeñalRESUMEN
Differentiation-inducing factor-1 (DIF-1) isolated from Dictyostelium discoideum strongly inhibits the proliferation of various mammalian cells through the activation of glycogen synthase kinase-3 (GSK-3). To evaluate DIF-1 as a novel anti-cancer agent for malignant melanoma, we examined whether DIF-1 has anti-proliferative, anti-migratory, and anti-invasive effects on melanoma cells using in vitro and in vivo systems. DIF-1 reduced the expression levels of cyclin D1 and c-Myc by facilitating their degradation via GSK-3 in mouse (B16BL6) and human (A2058) malignant melanoma cells, and thereby strongly inhibited their proliferation. DIF-1 suppressed the canonical Wnt signaling pathway by lowering the expression levels of transcription factor 7-like 2 and ß-catenin, key transcription factors in this pathway. DIF-1 also inhibited cell migration and invasion, reducing the expression of matrix metalloproteinase-2; however, this effect was not dependent on GSK-3 activity. In a mouse lung tumor formation model, repeated oral administrations of DIF-1 markedly reduced melanoma colony formation in the lung. These results suggest that DIF-1 inhibits cell proliferation by a GSK-3-dependent mechanism and suppresses cell migration and invasion by a GSK-3-independent mechanism. Therefore, DIF-1 may have a potential as a novel anti-cancer agent for the treatment of malignant melanoma.
Asunto(s)
Antineoplásicos/uso terapéutico , Glucógeno Sintasa Quinasa 3/metabolismo , Hexanonas/uso terapéutico , Hidrocarburos Clorados/uso terapéutico , Melanoma/tratamiento farmacológico , Proteínas de Neoplasias/metabolismo , Vía de Señalización Wnt/efectos de los fármacos , Animales , Antineoplásicos/efectos adversos , Antineoplásicos/farmacología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Femenino , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/genética , Hexanonas/efectos adversos , Hexanonas/farmacología , Humanos , Hidrocarburos Clorados/efectos adversos , Hidrocarburos Clorados/farmacología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Melanoma/metabolismo , Melanoma/patología , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C57BL , Invasividad Neoplásica/patología , Invasividad Neoplásica/prevención & control , Proteínas de Neoplasias/agonistas , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/genética , Interferencia de ARN , Distribución Aleatoria , Carga Tumoral/efectos de los fármacosRESUMEN
The epithelial-mesenchymal transition (EMT) is implicated in tumorigenesis and cancer progression, and canonical Wnt signaling tightly controls Snail, a key transcriptional repressor of EMT. While the suppression of canonical Wnt signaling and EMT comprises an attractive therapeutic strategy, molecular targets for small molecules reverting Wnt and EMT have not been widely studied. Meanwhile, the anti-helminthic niclosamide has been identified as a potent inhibitor of many oncogenic signaling pathways although its molecular targets have not yet been clearly identified. In this study, we show that niclosamide directly targets Axin-GSK3 interaction, at least in part, resulting in suppression of Wnt/Snail-mediated EMT. In vitro and in vivo, disruption of Axin-GSK3 complex by niclosamide induces mesenchymal to epithelial reversion at nM concentrations, accompanied with suppression of the tumorigenic potential of colon cancer. Niclosamide treatment successfully attenuates Snail abundance while increasing E-cadherin abundance in xenograft tumor. Notably, oral administration of niclosamide significantly suppressed adenoma formation in an APC-MIN mice model, indicating that niclosamide is an effective therapeutic for familial adenomatosis polyposis (FAP) patients. In this study, we identified a novel target to control the canonical Wnt pathway and Snail-mediated EMT program, and discovered a repositioned therapeutics for FAP patients.
Asunto(s)
Poliposis Adenomatosa del Colon/metabolismo , Proteína Axina/metabolismo , Glucógeno Sintasa Quinasa 3/metabolismo , Niclosamida/farmacología , Poliposis Adenomatosa del Colon/tratamiento farmacológico , Poliposis Adenomatosa del Colon/genética , Animales , Proteína Axina/química , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Transición Epitelial-Mesenquimal/efectos de los fármacos , Glucógeno Sintasa Quinasa 3/química , Xenoinjertos , Ratones , Modelos Moleculares , Conformación Molecular , Niclosamida/química , Unión Proteica/efectos de los fármacos , Vía de Señalización Wnt/efectos de los fármacosRESUMEN
Glycogen synthase kinase-3 (GSK-3) is an unusual protein-serine kinase in that it is primarily regulated by inhibition and lies downstream of multiple cell signaling pathways. This raises a variety of questions in terms of its physiological role(s), how signaling specificity is maintained and why so many eggs have been placed into one basket. There are actually two baskets, as there are two isoforms, GSK-3α and ß, that are highly related and largely redundant. Their many substrates range from regulators of cellular metabolism to molecules that control growth and differentiation. In this chapter, we review the characteristics of GSK-3, update progress in understanding the kinase, and try to answer some of the questions raised by its unusual properties. Indeed, the kinase may trigger transformation in our thinking of how cellular signals are organized and controlled.
Asunto(s)
Glucógeno Sintasa Quinasa 3/metabolismo , Transducción de Señal , Secuencia de Aminoácidos , Animales , Glucógeno Sintasa Quinasa 3/química , Glucógeno Sintasa Quinasa 3/genética , Humanos , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Modelos Biológicos , Terapia Molecular Dirigida , Especificidad por SustratoRESUMEN
The authentic standards 2-(cyclopropanecarboxamido)-N-(4-methoxypyridin-3-yl)isonicotinamide (4a) and 2-(cyclopropanecarboxamido)-N-(4-(4-methoxyphenyl)pyridin-3-yl)isonicotinamide (7a), and their corresponding precursors 2-(cyclopropanecarboxamido)-N-(4-hydroxypyridin-3-yl)isonicotinamide (4b) and 2-(cyclopropanecarboxamido)-N-(4-(4-hydroxyphenyl)pyridin-3-yl)isonicotinamide (7b) were synthesized from methyl 2-aminoisonicotinate and cyclopropanecarbonyl chloride with overall chemical yield 47% in three steps, 22% in four steps, 40% in three steps, and 17% in four steps, respectively. The target tracers 2-(cyclopropanecarboxamido)-N-(4-[11C]methoxypyridin-3-yl)isonicotinamide ([11C]4a) and 2-(cyclopropanecarboxamido)-N-(4-(4-[11C]methoxyphenyl)pyridin-3-yl)isonicotinamide ([11C]7a) were prepared from the precursors (4b and 7b) with [11C]CH3OTf through O-[11C]methylation and isolated by HPLC combined with SPE in 40-50% radiochemical yield, based on [11C]CO2 and decay corrected to end of bombardment (EOB). The radiochemical purity was >99%, and the specific activity (SA) at EOB was 370-1110GBq/µmol with a total synthesis time of â¼40-min from EOB.