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1.
Int J Mol Sci ; 24(6)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36982411

RESUMO

It is extremely difficult to achieve functional recovery after axonal injury in the adult central nervous system. The activation of G-protein coupled receptor 110 (GPR110, ADGRF1) has been shown to stimulate neurite extension in developing neurons and after axonal injury in adult mice. Here, we demonstrate that GPR110 activation partially restores visual function impaired by optic nerve injury in adult mice. Intravitreal injection of GPR110 ligands, synaptamide and its stable analogue dimethylsynaptamide (A8) after optic nerve crush significantly reduced axonal degeneration and improved axonal integrity and visual function in wild-type but not gpr110 knockout mice. The retina obtained from the injured mice treated with GPR110 ligands also showed a significant reduction in the crush-induced loss of retinal ganglion cells. Our data suggest that targeting GPR110 may be a viable strategy for functional recovery after optic nerve injury.


Assuntos
Traumatismos do Nervo Óptico , Animais , Camundongos , Axônios , Ligantes , Camundongos Knockout , Compressão Nervosa , Regeneração Nervosa/fisiologia , Receptores Acoplados a Proteínas G/genética , Retina , Células Ganglionares da Retina/fisiologia
2.
J Chem Inf Model ; 62(5): 1249-1258, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35103473

RESUMO

Nontypeable Haemophilus influenzae (NTHi) are clinically important Gram-negative bacteria that are responsible for various human mucosal diseases, including otitis media (OM). Recurrent OM caused by NTHi is common, and infections that recur less than 2 weeks following antimicrobial therapy are largely attributable to the recurrence of the same strain of bacteria. Toxin-antitoxin (TA) modules encoded by bacteria enable rapid responses to environmental stresses and are thought to facilitate growth arrest, persistence, and tolerance to antibiotics. The vapBC-1 locus of NTHi encodes a type II TA system, comprising the ribonuclease toxin VapC1 and its cognate antitoxin VapB1. The activity of VapC1 has been linked to the survival of NTHi during antibiotic treatment both in vivo and ex vivo. Therefore, inhibitors of VapC1 might serve as adjuvants to antibiotics, preventing NTHi from entering growth arrest and surviving; however, none have been reported to date. A truncated VapB1 peptide from a crystal structure of the VapBC-1 complex was used to generate pharmacophore queries to facilitate a scaffold hopping approach for the identification of small-molecule VapC1 inhibitors. The National Center for Advancing Translational Sciences small-molecule library was virtually screened using the shape-based method rapid overlay of chemical structures (ROCS), and the top-ranking hits were docked into the VapB1 binding pocket of VapC1. Two hundred virtual screening hits with the best docking scores were selected and tested in a biochemical VapC1 activity assay, which confirmed eight compounds as VapC1 inhibitors. An additional 60 compounds were selected with structural similarities to the confirmed VapC1 inhibitors, of which 20 inhibited VapC1 activity. Intracellular target engagement of five inhibitors was indicated by the destabilization of VapC1 within bacterial cells from a cellular thermal shift assay; however, no impact on bacterial growth was observed. Thus, this virtual screening and scaffold hopping approach enabled the discovery of VapC1 ribonuclease inhibitors that might serve as starting points for preclinical development.


Assuntos
Antitoxinas , Toxinas Bacterianas , Antitoxinas/química , Proteínas de Bactérias/química , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , Haemophilus influenzae/química , Haemophilus influenzae/metabolismo , Humanos , Ribonucleases/metabolismo
3.
J Chem Inf Model ; 62(7): 1783-1793, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35357819

RESUMO

Despite the potency of most first-line anti-cancer drugs, nonadherence to these drug regimens remains high and is attributable to the prevalence of "off-target" drug effects that result in serious adverse events (SAEs) like hair loss, nausea, vomiting, and diarrhea. Some anti-cancer drugs are converted by liver uridine 5'-diphospho-glucuronosyltransferases through homeostatic host metabolism to form drug-glucuronide conjugates. These sugar-conjugated metabolites are generally inactive and can be safely excreted via the biliary system into the gastrointestinal tract. However, ß-glucuronidase (ßGUS) enzymes expressed by commensal gut bacteria can remove the glucuronic acid moiety, producing the reactivated drug and triggering dose-limiting side effects. Small-molecule ßGUS inhibitors may reduce this drug-induced gut toxicity, allowing patients to complete their full course of treatment. Herein, we report the discovery of novel chemical series of ßGUS inhibitors by structure-based virtual high-throughput screening (vHTS). We developed homology models for ßGUS and applied them to large-scale vHTS against nearly 400,000 compounds within the chemical libraries of the National Center for Advancing Translational Sciences at the National Institutes of Health. From the vHTS results, we cherry-picked 291 compounds via a multifactor prioritization procedure, providing 69 diverse compounds that exhibited positive inhibitory activity in a follow-up ßGUS biochemical assay in vitro. Our findings correspond to a hit rate of 24% and could inform the successful downstream development of a therapeutic adjunct that targets the human microbiome to prevent SAEs associated with first-line, standard-of-care anti-cancer drugs.


Assuntos
Antineoplásicos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Microbiota , Neoplasias , Antineoplásicos/efeitos adversos , Detecção Precoce de Câncer , Inibidores Enzimáticos/farmacologia , Glicoproteínas , Humanos
4.
Int J Mol Sci ; 22(7)2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33806166

RESUMO

Recovery from axonal injury is extremely difficult, especially for adult neurons. Here, we demonstrate that the activation of G-protein coupled receptor 110 (GPR110, ADGRF1) is a mechanism to stimulate axon growth after injury. N-docosahexaenoylethanolamine (synaptamide), an endogenous ligand of GPR110 that promotes neurite outgrowth and synaptogenesis in developing neurons, and a synthetic GPR110 ligand stimulated neurite growth in axotomized cortical neurons and in retinal explant cultures. Intravitreal injection of GPR110 ligands following optic nerve crush injury promoted axon extension in adult wild-type, but not in gpr110 knockout, mice. In vitro axotomy or in vivo optic nerve injury rapidly induced the neuronal expression of gpr110. Activating the developmental mechanism of neurite outgrowth by specifically targeting GPR110 that is upregulated upon injury may provide a novel strategy for stimulating axon growth after nerve injury in adults.


Assuntos
Axônios/metabolismo , Etanolaminas/farmacologia , Regeneração Nervosa , Receptores Acoplados a Proteínas G/metabolismo , Animais , Feminino , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microfluídica , Simulação de Acoplamento Molecular , Compressão Nervosa , Neurogênese , Neurônios/metabolismo , Nervo Óptico/metabolismo , Retina/metabolismo
5.
FASEB J ; 33(11): 12435-12446, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31419161

RESUMO

Fibrosis is an underlying cause of cirrhosis and hepatic failure resulting in end stage liver disease with limited pharmacological options. The beneficial effects of relaxin peptide treatment were demonstrated in clinically relevant animal models of liver fibrosis. However, the use of relaxin is problematic because of a short half-life. The aim of this study was to test the therapeutic effects of recently identified small molecule agonists of the human relaxin receptor, relaxin family peptide receptor 1 (RXFP1). The lead compound of this series, ML290, was selected based on its effects on the expression of fibrosis-related genes in primary human stellate cells. RNA sequencing analysis of TGF-ß1-activated LX-2 cells showed that ML290 treatment primarily affected extracellular matrix remodeling and cytokine signaling, with expression profiles indicating an antifibrotic effect of ML290. ML290 treatment in human liver organoids with LPS-induced fibrotic phenotype resulted in a significant reduction of type I collagen. The pharmacokinetics of ML290 in mice demonstrated its high stability in vivo, as evidenced by the sustained concentrations of compound in the liver. In mice expressing human RXFP1 gene treated with carbon tetrachloride, ML290 significantly reduced collagen content, α-smooth muscle actin expression, and cell proliferation around portal ducts. In conclusion, ML290 demonstrated antifibrotic effects in liver fibrosis.-Kaftanovskaya, E. M., Ng, H. H., Soula, M., Rivas, B., Myhr, C., Ho, B. A., Cervantes, B. A., Shupe, T. D., Devarasetty, M., Hu, X., Xu, X., Patnaik, S., Wilson, K. J., Barnaeva, E., Ferrer, M., Southall, N. T., Marugan, J. J., Bishop, C. E., Agoulnik, I. U., Agoulnik, A. I. Therapeutic effects of a small molecule agonist of the relaxin receptor ML290 in liver fibrosis.


Assuntos
Intoxicação por Tetracloreto de Carbono/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Cirrose Hepática/tratamento farmacológico , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores de Peptídeos/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Animais , Intoxicação por Tetracloreto de Carbono/genética , Linhagem Celular Transformada , Proliferação de Células/genética , Citocinas/genética , Citocinas/metabolismo , Humanos , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Camundongos , Camundongos Transgênicos , Organoides/metabolismo , Organoides/patologia , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo , Transdução de Sinais/genética
6.
Regul Toxicol Pharmacol ; 116: 104716, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32619635

RESUMO

Pancreatic cancer is a leading cause of cancer-related deaths in the U.S. Ninety percent of patients with stage IV pancreatic cancer die within one year of diagnosis due to complications of metastasis. A metastatic potential of cancer cells has been shown to be closely associated with formation of perinucleolar compartment (PNC). Metarrestin, a first-in-class PNC inhibitor, was evaluated for its toxicity, toxicokinetics, and safety pharmacology in beagle dogs following every other day oral (capsule) administration for 28 days to support its introduction into clinical trials. The study consisted of four dose groups: vehicle; 0.25, 0.75 and 1.50 mg/kg/dose. Metarrestin reached its maximum concentration in blood at 3 h (overall median Tmax) across all doses with a mean t1/2 over 168 h of 55.5 h. Dose dependent increase in systemic exposure (Cmax and AUClast) with no sex difference was observed on days 1 and 27. Metarrestin accumulated from Day 1 to Day 27 at all dose levels and in both sexes by an overall factor of about 2.34. No mortality occurred during the dosing period; however, treatment-related clinical signs of toxicity consisting of hypoactivity, shaking/shivering, thinness, irritability, salivation, abnormal gait, tremors, ataxia and intermittent seizure-like activity were seen in both sexes at mid and high dose groups. Treatment-related effects on body weight and food consumption were seen at the mid and high dose levels. Safety pharmacology study showed no treatment-related effects on blood pressure, heart rate, corrected QT, PR, RR, or QRS intervals, or respiratory function parameters (respiratory rate, tidal volume, minute volume). There were no histopathological changes observed, with the exception of transient thymic atrophy which was considered to be non-adverse. Based primarily on clinical signs of toxicity, the No Observed Adverse Effect Level (NOAEL) in dogs was considered to be 0.25 mg/kg metarrestin after every other day dosing for 28 days with a mean of male and female Cmax = 82.5 ng/mL and AUClast = 2521 h*ng/mL, on Day 27.


Assuntos
Antineoplásicos , Pirimidinas , Pirróis , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Antineoplásicos/toxicidade , Cães , Avaliação Pré-Clínica de Medicamentos , Canal de Potássio ERG1/genética , Canal de Potássio ERG1/fisiologia , Feminino , Células HEK293 , Humanos , Masculino , Nível de Efeito Adverso não Observado , Neoplasias Pancreáticas/tratamento farmacológico , Pirimidinas/administração & dosagem , Pirimidinas/farmacocinética , Pirimidinas/toxicidade , Pirróis/administração & dosagem , Pirróis/farmacocinética , Pirróis/toxicidade
7.
Bioorg Med Chem Lett ; 29(9): 1113-1119, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30852083

RESUMO

Nonstructural protein 1 (NS1) plays a crucial function in the replication, spread, and pathogenesis of influenza virus by inhibiting the host innate immune response. Here we report the discovery and optimization of novel pyrazolopyridine NS1 antagonists that can potently inhibit influenza A/PR/8/34 replication in MDCK cells, rescue MDCK cells from cytopathic effects of seasonal influenza A strains, reverse NS1-dependent inhibition of IFN-ß gene expression, and suppress the slow growth phenotype in NS1-expressing yeast. These pyrazolopyridines will enable researchers to investigate NS1 function during infection and how antagonists can be utilized in the next generation of treatments for influenza infection.


Assuntos
Antivirais/síntese química , Desenho de Fármacos , Vírus da Influenza A/metabolismo , Pirazóis/química , Piridinas/química , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/metabolismo , Antivirais/farmacologia , Cães , Células HEK293 , Meia-Vida , Humanos , Interferon beta/metabolismo , Células Madin Darby de Rim Canino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pirazóis/metabolismo , Pirazóis/farmacologia , Piridinas/metabolismo , Piridinas/farmacologia , Relação Estrutura-Atividade , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacos
8.
J Neurosci ; 36(29): 7693-706, 2016 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-27445146

RESUMO

UNLABELLED: Parkinson's disease (PD) is characterized by the accumulation of α-synuclein (α-syn) within Lewy body inclusions in the nervous system. There are currently no disease-modifying therapies capable of reducing α-syn inclusions in PD. Recent data has indicated that loss-of-function mutations in the GBA1 gene that encodes lysosomal ß-glucocerebrosidase (GCase) represent an important risk factor for PD, and can lead to α-syn accumulation. Here we use a small-molecule modulator of GCase to determine whether GCase activation within lysosomes can reduce α-syn levels and ameliorate downstream toxicity. Using induced pluripotent stem cell (iPSC)-derived human midbrain dopamine (DA) neurons from synucleinopathy patients with different PD-linked mutations, we find that a non-inhibitory small molecule modulator of GCase specifically enhanced activity within lysosomal compartments. This resulted in reduction of GCase substrates and clearance of pathological α-syn, regardless of the disease causing mutations. Importantly, the reduction of α-syn was sufficient to reverse downstream cellular pathologies induced by α-syn, including perturbations in hydrolase maturation and lysosomal dysfunction. These results indicate that enhancement of a single lysosomal hydrolase, GCase, can effectively reduce α-syn and provide therapeutic benefit in human midbrain neurons. This suggests that GCase activators may prove beneficial as treatments for PD and related synucleinopathies. SIGNIFICANCE STATEMENT: The presence of Lewy body inclusions comprised of fibrillar α-syn within affected regions of PD brain has been firmly documented, however no treatments exist that are capable of clearing Lewy bodies. Here, we used a mechanistic-based approach to examine the effect of GCase activation on α-syn clearance in human midbrain DA models that naturally accumulate α-syn through genetic mutations. Small molecule-mediated activation of GCase was effective at reducing α-syn inclusions in neurons, as well as associated downstream toxicity, demonstrating a therapeutic effect. Our work provides an example of how human iPSC-derived midbrain models could be used for testing potential treatments for neurodegenerative disorders, and identifies GCase as a critical therapeutic convergence point for a wide range of synucleinopathies.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Glucosilceramidase/metabolismo , Lisossomos/metabolismo , Mesencéfalo/patologia , Doença de Parkinson/patologia , alfa-Sinucleína/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular Tumoral , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/ultraestrutura , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Humanos , Células-Tronco Pluripotentes Induzidas , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Mutação/genética , Neuroblastoma/patologia , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , ATPases Translocadoras de Prótons/metabolismo , Frações Subcelulares/metabolismo , Frações Subcelulares/patologia , Sinaptofisina/metabolismo
9.
J Neurosci ; 36(28): 7441-52, 2016 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-27413154

RESUMO

UNLABELLED: Among the known genetic risk factors for Parkinson disease, mutations in GBA1, the gene responsible for the lysosomal disorder Gaucher disease, are the most common. This genetic link has directed attention to the role of the lysosome in the pathogenesis of parkinsonism. To study how glucocerebrosidase impacts parkinsonism and to evaluate new therapeutics, we generated induced human pluripotent stem cells from four patients with Type 1 (non-neuronopathic) Gaucher disease, two with and two without parkinsonism, and one patient with Type 2 (acute neuronopathic) Gaucher disease, and differentiated them into macrophages and dopaminergic neurons. These cells exhibited decreased glucocerebrosidase activity and stored the glycolipid substrates glucosylceramide and glucosylsphingosine, demonstrating their similarity to patients with Gaucher disease. Dopaminergic neurons from patients with Type 2 and Type 1 Gaucher disease with parkinsonism had reduced dopamine storage and dopamine transporter reuptake. Levels of α-synuclein, a protein present as aggregates in Parkinson disease and related synucleinopathies, were selectively elevated in neurons from the patients with parkinsonism or Type 2 Gaucher disease. The cells were then treated with NCGC607, a small-molecule noninhibitory chaperone of glucocerebrosidase identified by high-throughput screening and medicinal chemistry structure optimization. This compound successfully chaperoned the mutant enzyme, restored glucocerebrosidase activity and protein levels, and reduced glycolipid storage in both iPSC-derived macrophages and dopaminergic neurons, indicating its potential for treating neuronopathic Gaucher disease. In addition, NCGC607 reduced α-synuclein levels in dopaminergic neurons from the patients with parkinsonism, suggesting that noninhibitory small-molecule chaperones of glucocerebrosidase may prove useful for the treatment of Parkinson disease. SIGNIFICANCE STATEMENT: Because GBA1 mutations are the most common genetic risk factor for Parkinson disease, dopaminergic neurons were generated from iPSC lines derived from patients with Gaucher disease with and without parkinsonism. These cells exhibit deficient enzymatic activity, reduced lysosomal glucocerebrosidase levels, and storage of glucosylceramide and glucosylsphingosine. Lines generated from the patients with parkinsonism demonstrated elevated levels of α-synuclein. To reverse the observed phenotype, the neurons were treated with a novel noninhibitory glucocerebrosidase chaperone, which successfully restored glucocerebrosidase activity and protein levels and reduced glycolipid storage. In addition, the small-molecule chaperone reduced α-synuclein levels in dopaminergic neurons, indicating that chaperoning glucocerebrosidase to the lysosome may provide a novel therapeutic strategy for both Parkinson disease and neuronopathic forms of Gaucher disease.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Doença de Gaucher/patologia , Glucosilceramidas/antagonistas & inibidores , Glicolipídeos/metabolismo , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Transtornos Parkinsonianos/patologia , alfa-Sinucleína/metabolismo , Acetanilidas/farmacologia , Benzamidas/farmacologia , Catecolaminas/metabolismo , Diferenciação Celular/genética , Neurônios Dopaminérgicos/efeitos dos fármacos , Feminino , Glucosilceramidase , Glucosilceramidas/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Potenciais Pós-Sinápticos Inibidores/genética , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/genética , Mutação/genética , Técnicas de Patch-Clamp , beta-Glucosidase/genética
10.
Expert Rev Proteomics ; 13(5): 471-9, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27098312

RESUMO

Gaucher disease, caused by pathological mutations GBA1, encodes the lysosome-resident enzyme glucocerebrosidase, which cleaves glucosylceramide into glucose and ceramide. In Gaucher disease, glucocerebrosidase deficiency leads to lysosomal accumulation of substrate, primarily in cells of the reticulo-endothelial system. Gaucher disease has broad clinical heterogeneity, and mutations in GBA1 are a risk factor for the development of different synucleinopathies. Insights into the cell biology and biochemistry of glucocerebrosidase have led to new therapeutic approaches for Gaucher disease including small chemical chaperones. Such chaperones facilitate proper enzyme folding and translocation to lysosomes, thereby preventing premature breakdown of the enzyme in the proteasome. This review discusses recent progress in developing chemical chaperones as a therapy for Gaucher disease, with implications for the treatment of synucleinopathies. It focuses on the development of non-inhibitory glucocerebrosidase chaperones and their therapeutic advantages over inhibitory chaperones, as well as the challenges involved in identifying and validating chemical chaperones.


Assuntos
Doença de Gaucher/tratamento farmacológico , Glucosilceramidase/efeitos dos fármacos , Doença de Gaucher/enzimologia , Glucosilceramidase/genética , Glucosilceramidase/metabolismo , Humanos , Mutação , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Dobramento de Proteína/efeitos dos fármacos , Sinucleínas/efeitos dos fármacos , Sinucleínas/genética
11.
Nucleic Acids Res ; 42(10): 6591-602, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24799433

RESUMO

Myotonic dystrophy type 1 (DM1) is a dominantly inherited neuromuscular disorder resulting from expression of RNA containing an expanded CUG repeat (CUG(exp)). The pathogenic RNA is retained in nuclear foci. Poly-(CUG) binding proteins in the Muscleblind-like (MBNL) family are sequestered in foci, causing misregulated alternative splicing of specific pre-mRNAs. Inhibitors of MBNL1-CUG(exp) binding have been shown to restore splicing regulation and correct phenotypes in DM1 models. We therefore conducted a high-throughput screen to identify novel inhibitors of MBNL1-(CUG)12 binding. The most active compound was lomofungin, a natural antimicrobial agent. We found that lomofungin undergoes spontaneous dimerization in DMSO, producing dilomofungin, whose inhibition of MBNL1-(CUG)12 binding was 17-fold more potent than lomofungin itself. However, while dilomofungin displayed the desired binding characteristics in vitro, when applied to cells it produced a large increase of CUG(exp) RNA in nuclear foci, owing to reduced turnover of the CUG(exp) transcript. By comparison, the monomer did not induce CUG(exp) accumulation in cells and was more effective at rescuing a CUG(exp)-induced splicing defect. These results support the feasibility of high-throughput screens to identify compounds targeting toxic RNA, but also demonstrate that ligands for repetitive sequences may have unexpected effects on RNA decay.


Assuntos
Fenazinas/farmacologia , Proteínas de Ligação a RNA/metabolismo , RNA/química , RNA/metabolismo , Regiões 3' não Traduzidas , Processamento Alternativo/efeitos dos fármacos , Dimerização , Humanos , Fenazinas/química , Fenazinas/metabolismo , Estabilidade de RNA/efeitos dos fármacos , Sequências Repetitivas de Ácido Nucleico
12.
J Biol Chem ; 289(23): 16349-61, 2014 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-24755226

RESUMO

Eya proteins are essential co-activators of the Six family of transcription factors and contain a unique tyrosine phosphatase domain belonging to the haloacid dehalogenase family of phosphatases. The phosphatase activity of Eya is important for the transcription of a subset of Six1-target genes, and also directs cells to the repair rather than apoptosis pathway upon DNA damage. Furthermore, Eya phosphatase activity has been shown to mediate transformation, invasion, migration, and metastasis of breast cancer cells, making it a potential new drug target for breast cancer. We have previously identified a class of N-arylidenebenzohydrazide compounds that specifically inhibit the Eya2 phosphatase. Herein, we demonstrate that these compounds are reversible inhibitors that selectively inhibit the phosphatase activity of Eya2, but not Eya3. Our mutagenesis results suggest that this class of compounds does not bind to the active site and the binding does not require the coordination with Mg(2+). Moreover, these compounds likely bind within a site on the opposite face of the active site, and function as allosteric inhibitors. We also demonstrate that this class of compounds inhibits Eya2 phosphatase-mediated cell migration, setting the foundation for these molecules to be developed into chemical probes for understanding the specific function of the Eya2 phosphatase and to serve as a prototype for the development of Eya2 phosphatase specific anti-cancer drugs.


Assuntos
Movimento Celular/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Proteínas Nucleares/antagonistas & inibidores , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Regulação Alostérica , Sequência de Aminoácidos , Calorimetria , Linhagem Celular , Cristalografia por Raios X , Inibidores Enzimáticos/farmacologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Magnésio/metabolismo , Simulação de Acoplamento Molecular , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Proteínas Nucleares/fisiologia , Ligação Proteica , Proteínas Tirosina Fosfatases/química , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Tirosina Fosfatases/fisiologia , Homologia de Sequência de Aminoácidos , Espectrofotometria Ultravioleta
13.
J Neurosci ; 33(24): 10132-42, 2013 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-23761908

RESUMO

The Neuropeptide S receptor, a Gs/Gq-coupled GPCR expressed in brain regions involved in mediating drug reward, has recently emerged as a candidate therapeutic target in addictive disorders. Here, we describe the in vitro and in vivo pharmacology of a novel, selective and brain penetrant NPSR antagonist with nanomolar affinity for the NPSR, NCGC00185684. In vitro, NCGC00185684 shows biased antagonist properties, and preferentially blocks ERK-phosphorylation over intracellular cAMP or calcium responses to NPS. In vivo, systemic NCGC00185684 blocks alcohol-induced ERK-phosphorylation in the rat central amygdala, a region involved in regulation of alcohol intake. NCGC00185684 also decreases operant alcohol self-administration, and lowers motivation for alcohol reward as measured using progressive ratio responding. These effects are behaviorally specific, in that they are observed at doses that do not influence locomotor activity or reinstatement responding following extinction. Together, these data provide an initial validation of the NPSR as a therapeutic target in alcoholism.


Assuntos
Tonsila do Cerebelo/efeitos dos fármacos , Depressores do Sistema Nervoso Central/administração & dosagem , Condicionamento Operante/efeitos dos fármacos , Etanol/administração & dosagem , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Receptores de Neuropeptídeos/antagonistas & inibidores , Análise de Variância , Animais , Cricetinae , Cricetulus , Sinais (Psicologia) , Interações Medicamentosas , Transferência Ressonante de Energia de Fluorescência , Humanos , Imidazóis/farmacologia , Técnicas In Vitro , Locomoção/efeitos dos fármacos , Masculino , Compostos Organotiofosforados/farmacologia , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Ensaio Radioligante , Ratos , Ratos Wistar , Receptores de Neuropeptídeos/metabolismo , Reflexo/efeitos dos fármacos , Esquema de Reforço , Reforço Psicológico , Sacarina/administração & dosagem , Autoadministração , Edulcorantes/administração & dosagem , Transfecção
14.
Eur J Med Chem ; 259: 115632, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37453329

RESUMO

Recent Alzheimer's research has shown increasing interest in the caspase-2 (Casp2) enzyme. However, the available Casp2 inhibitors, which have been pentapeptides or peptidomimetics, face challenges for use as CNS drugs. In this study, we successfully screened a 1920-compound chloroacetamide-based, electrophilic fragment library from Enamine. Our two-point dose screen identified 64 Casp2 hits, which were further evaluated in a ten-point dose-response study to assess selectivity over Casp3. We discovered compounds with inhibition values in the single-digit micromolar and sub-micromolar range, as well as up to 32-fold selectivity for Casp2 over Casp3. Target engagement analysis confirmed the covalent-irreversible binding of the selected fragments to Cys320 at the active site of Casp2. Overall, our findings lay a strong foundation for the future development of small-molecule Casp2 inhibitors.


Assuntos
Caspase 2 , Inibidores de Caspase , Caspase 2/metabolismo , Caspase 3/metabolismo , Domínio Catalítico , Inibidores de Caspase/química
15.
ACS Chem Biol ; 18(4): 969-981, 2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-36976909

RESUMO

Target class profiling (TCP) is a chemical biology approach to investigate understudied biological target classes. TCP is achieved by developing a generalizable assay platform and screening curated compound libraries to interrogate the chemical biological space of members of an enzyme family. In this work, we took a TCP approach to investigate inhibitory activity across a set of small-molecule methyltransferases (SMMTases), a subclass of methyltransferase enzymes, with the goal of creating a launchpad to explore this largely understudied target class. Using the representative enzymes nicotinamide N-methyltransferase (NNMT), phenylethanolamine N-methyltransferase (PNMT), histamine N-methyltransferase (HNMT), glycine N-methyltransferase (GNMT), catechol O-methyltransferase (COMT), and guanidinoacetate N-methyltransferase (GAMT), we optimized high-throughput screening (HTS)-amenable assays to screen 27,574 unique small molecules against all targets. From this data set, we identified a novel inhibitor which selectively inhibits the SMMTase HNMT and demonstrated how this platform approach can be leveraged for a targeted drug discovery campaign using the example of HNMT.


Assuntos
Histamina N-Metiltransferase , Metiltransferases , Metiltransferases/química , Ensaios de Triagem em Larga Escala , Descoberta de Drogas
16.
Autophagy Rep ; 2(1)2023.
Artigo em Inglês | MEDLINE | ID: mdl-37064812

RESUMO

Many neurodegenerative diseases, including Huntington's disease (HD) and Alzheimer's disease (AD), occur due to an accumulation of aggregation-prone proteins, which results in neuronal death. Studies in animal and cell models show that reducing the levels of these proteins mitigates disease phenotypes. We previously reported a small molecule, NCT-504, which reduces cellular levels of mutant huntingtin (mHTT) in patient fibroblasts as well as mouse striatal and cortical neurons from an HdhQ111 mutant mouse. Here, we show that NCT-504 has a broader potential, and in addition reduces levels of Tau, a protein associated with Alzheimer's disease, as well as other tauopathies. We find that in untreated cells, Tau and mHTT are degraded via autophagy. Notably, treatment with NCT-504 diverts these proteins to multivesicular bodies (MVB) and the ESCRT pathway. Specifically, NCT-504 causes a proliferation of endolysosomal organelles including MVB, and an enhanced association of mHTT and Tau with endosomes and MVB. Importantly, depletion of proteins that act late in the ESCRT pathway blocked NCT-504 dependent degradation of Tau. Moreover, NCT-504-mediated degradation of Tau occurred in cells where Atg7 is depleted, which indicates that this pathway is independent of canonical autophagy. Together, these studies reveal that upregulation of traffic through an ESCRT-dependent MVB pathway may provide a therapeutic approach for neurodegenerative diseases.

17.
Nat Cancer ; 4(3): 365-381, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36914816

RESUMO

Adult liver malignancies, including intrahepatic cholangiocarcinoma and hepatocellular carcinoma, are the second leading cause of cancer-related deaths worldwide. Most individuals are treated with either combination chemotherapy or immunotherapy, respectively, without specific biomarkers for selection. Here using high-throughput screens, proteomics and in vitro resistance models, we identify the small molecule YC-1 as selectively active against a defined subset of cell lines derived from both liver cancer types. We demonstrate that selectivity is determined by expression of the liver-resident cytosolic sulfotransferase enzyme SULT1A1, which sulfonates YC-1. Sulfonation stimulates covalent binding of YC-1 to lysine residues in protein targets, enriching for RNA-binding factors. Computational analysis defined a wider group of structurally related SULT1A1-activated small molecules with distinct target profiles, which together constitute an untapped small-molecule class. These studies provide a foundation for preclinical development of these agents and point to the broader potential of exploiting SULT1A1 activity for selective targeting strategies.


Assuntos
Alquilantes , Neoplasias Hepáticas , Humanos , Sulfotransferases , Neoplasias Hepáticas/tratamento farmacológico , Arilsulfotransferase
18.
ACS Chem Biol ; 17(12): 3290-3297, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36469692

RESUMO

Autophagy is a conserved metabolic pathway that is central to many diseases. Recently, there has been a lot of interest in targeting autophagy with small molecule inhibitors as a possible therapeutic strategy. However, many of the compounds used for autophagy are nonselective. Here, we explored the inhibition of autophagy in pancreatic cancer cells using established selective small molecule inhibitors and discovered an unexpected link between the autophagy pathway and progression through the cell cycle. Our findings revealed that treatments with inhibitors that have different autophagy pathway targets block cell replication and activate other metabolic pathways to compensate for the blockade in autophagy. An unbiased screen looking for known drugs that might synergize with autophagy inhibition revealed new combination treatments that might provide a blueprint for therapeutic approaches to pancreatic cancer. The drugs quizartinib and THZ1 showed a strong synergistic effect in pancreatic cells with autophagy inhibition.


Assuntos
Autofagia , Ciclo Celular , Neoplasias Pancreáticas , Humanos , Autofagia/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Combinação de Medicamentos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas
19.
J Clin Transl Sci ; 6(1): e66, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35754433

RESUMO

There are numerous examples of translational science innovations addressing challenges in the translational process, accelerating progress along the translational spectrum, and generating solutions relevant to a wide range of human health needs. Examining these successes through an education lens can identify core principles and effective practices that lead to successful translational outcomes. The National Center for Advancing Translational Sciences (NCATS) is identifying and teaching these core principles and practices to a broad audience via online courses in translational science which teach from case studies of NCATS-led or supported research initiatives. In this paper, we share our approach to the design of these courses and offer a detailed description of our initial course, which focused on a preclinical drug discovery and development project spanning academic and government settings. Course participants were from a variety of career stages and institutions. Participants rated the course high in overall value to them and in providing a unique window into the translational science process. We share our model for course development as well as initial findings from the course evaluation with the goal of continuing to stimulate development of novel education activities teaching foundational principles in translational science to a broad audience.

20.
iScience ; 25(9): 104941, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36065186

RESUMO

Numerous studies have established the involvement of lysosomal and mitochondrial dysfunction in the pathogenesis of neurodegenerative disorders such as Alzheimer's and Parkinson diseases. Building on our previous studies of the neurodegenerative lysosomal lipidosis Niemann-Pick C1 (NPC1), we have unexpectedly discovered that activation of the mitochondrial chaperone tumor necrosis factor receptor-associated protein 1 (TRAP1) leads to the correction of the lysosomal storage phenotype in patient cells from multiple lysosomal storage disorders including NPC1. Using small compound activators specific for TRAP1, we find that activation of this chaperone leads to a generalized restoration of lysosomal and mitochondrial health. Mechanistically, we show that this process includes inhibition of oxidative phosphorylation and reduction of oxidative stress, which results in activation of AMPK and ultimately stimulates lysosome recycling. Thus, TRAP1 participates in lysosomal-mitochondrial crosstalk to maintain cellular homeostasis and could represent a potential therapeutic target for multiple disorders.

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