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1.
J Phys Chem Lett ; 11(11): 4430-4435, 2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-32392072

RESUMO

The pandemic outbreak of a new coronavirus (CoV), SARS-CoV-2, has captured the world's attention, demonstrating that CoVs represent a continuous global threat. As this is a highly contagious virus, it is imperative to understand RNA-dependent-RNA-polymerase (RdRp), the key component in virus replication. Although the SARS-CoV-2 genome shares 80% sequence identity with severe acute respiratory syndrome SARS-CoV, their RdRps and nucleotidyl-transferases (NiRAN) share 98.1% and 93.2% identity, respectively. Sequence alignment of six coronaviruses demonstrated higher identity among their RdRps (60.9%-98.1%) and lower identity among their Spike proteins (27%-77%). Thus, a 3D structural model of RdRp, NiRAN, non-structural protein 7 (nsp7), and nsp8 of SARS-CoV-2 was generated by modeling starting from the SARS counterpart structures. Furthermore, we demonstrate the binding poses of three viral RdRp inhibitors (Galidesivir, Favipiravir, and Penciclovir), which were recently reported to have clinical significance for SARS-CoV-2. The network of interactions established by these drug molecules affirms their efficacy to inhibit viral RNA replication and provides an insight into their structure-based rational optimization for SARS-CoV-2 inhibition.


Assuntos
Betacoronavirus/enzimologia , Nucleotidiltransferases/química , RNA Replicase/química , Adenina/análogos & derivados , Adenina/química , Adenina/metabolismo , Amidas/química , Amidas/metabolismo , Antivirais/química , Antivirais/metabolismo , Betacoronavirus/isolamento & purificação , Sítios de Ligação , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Humanos , Simulação de Acoplamento Molecular , Nucleotidiltransferases/metabolismo , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Estrutura Terciária de Proteína , Pirazinas/química , Pirazinas/metabolismo , Pirrolidinas/química , Pirrolidinas/metabolismo , RNA Replicase/metabolismo
2.
Plant Mol Biol ; 103(1-2): 225-234, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32140819

RESUMO

DNA N6-methyladenine (6 mA) is one of the most vital epigenetic modifications and involved in controlling the various gene expression levels. With the avalanche of DNA sequences generated in numerous databases, the accurate identification of 6 mA plays an essential role for understanding molecular mechanisms. Because the experimental approaches are time-consuming and costly, it is desirable to develop a computation model for rapidly and accurately identifying 6 mA. To the best of our knowledge, we first proposed a computational model named i6mA-Fuse to predict 6 mA sites from the Rosaceae genomes, especially in Rosa chinensis and Fragaria vesca. We implemented the five encoding schemes, i.e., mononucleotide binary, dinucleotide binary, k-space spectral nucleotide, k-mer, and electron-ion interaction pseudo potential compositions, to build the five, single-encoding random forest (RF) models. The i6mA-Fuse uses a linear regression model to combine the predicted probability scores of the five, single encoding-based RF models. The resultant species-specific i6mA-Fuse achieved remarkably high performances with AUCs of 0.982 and 0.978 and with MCCs of 0.869 and 0.858 on the independent datasets of Rosa chinensis and Fragaria vesca, respectively. In the F. vesca-specific i6mA-Fuse, the MBE and EIIP contributed to 75% and 25% of the total prediction; in the R. chinensis-specific i6mA-Fuse, Kmer, MBE, and EIIP contribute to 15%, 65%, and 20% of the total prediction. To assist high-throughput prediction for DNA 6 mA identification, the i6mA-Fuse is publicly accessible at https://kurata14.bio.kyutech.ac.jp/i6mA-Fuse/.


Assuntos
Adenina/análogos & derivados , DNA de Plantas/metabolismo , Rosaceae/metabolismo , Adenina/metabolismo , Algoritmos , Sítios de Ligação , Biologia Computacional , Conjuntos de Dados como Assunto , Aprendizado de Máquina , Modelos Genéticos , Rosaceae/genética
3.
Nucleic Acids Res ; 48(7): 3692-3707, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32133535

RESUMO

Alkylation is one of the most ubiquitous forms of DNA lesions. However, the motif preferences and substrates for the activity of the major types of alkylating agents defined by their nucleophilic substitution reactions (SN1 and SN2) are still unclear. Utilizing yeast strains engineered for large-scale production of single-stranded DNA (ssDNA), we probed the substrate specificity, mutation spectra and signatures associated with DNA alkylating agents. We determined that SN1-type agents preferably mutagenize double-stranded DNA (dsDNA), and the mutation signature characteristic of the activity of SN1-type agents was conserved across yeast, mice and human cancers. Conversely, SN2-type agents preferably mutagenize ssDNA in yeast. Moreover, the spectra and signatures derived from yeast were detectable in lung cancers, head and neck cancers and tumors from patients exposed to SN2-type alkylating chemicals. The estimates of mutation loads associated with the SN2-type alkylation signature were higher in lung tumors from smokers than never-smokers, pointing toward the mutagenic activity of the SN2-type alkylating carcinogens in cigarettes. In summary, our analysis of mutations in yeast strains treated with alkylating agents, as well as in whole-exome and whole-genome-sequenced tumors identified signatures highly specific to alkylation mutagenesis and indicate the pervasive nature of alkylation-induced mutagenesis in cancers.


Assuntos
Alquilantes/toxicidade , Mutagênese , Mutação , Neoplasias/genética , Adenina/química , Animais , DNA Glicosilases/metabolismo , DNA Fúngico/química , DNA de Cadeia Simples/química , Humanos , Camundongos , Leveduras/efeitos dos fármacos , Leveduras/genética , Leveduras/metabolismo
4.
Scand J Immunol ; 91(6): e12880, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32219875

RESUMO

Synthetic Toll-like receptor (TLR) 7 agonists have been suggested as immune modulators in a range of conditions. In contrast, self-derived TLR7 activators, such as RNA-containing immune complexes (RNA-IC), can contribute to autoimmune diseases due to endogenous immune activation. The exact difference in immune cell response between synthetic and endogenous TLR7 triggers is only partly known. An understanding of these differences could aid in the development of new therapeutic agents and provide insights into autoimmune disease mechanisms. We therefore compared the stimulatory capacity of two TLR7 agonists, RNA-IC and a synthetic small molecule DSR-6434, on blood leucocytes, plasmacytoid dendritic cells (pDCs) and B cells from healthy individuals. IFN-α, IL-6, IL-8 and TNF levels were measured by immunoassays, and gene expression in pDCs was analysed by an expression array. DSR-6434 triggered 20-fold lower levels of IFN-α by pDCs, but higher production of IL-6, IL-8 and TNF, compared to RNA-IC. Furthermore, IFN-α and TNF production were increased with exogenous IFN-α2b priming, whereas IL-8 synthesis by B cells was reduced for both stimuli. Cocultivation of pDCs and B cells increased the RNA-IC-stimulated IFN-α and TNF levels, while only IL-6 production was enhanced in the DSR-6434-stimulated cocultures. When comparing pDCs stimulated with RNA-IC and DSR-6434, twelve genes were differentially expressed (log2 fold change >2, adjusted P-value <.05). In conclusion, RNA-IC, which mimics an endogenous TLR7 stimulator, and the synthetic TLR7 agonist DSR-6434 trigger distinct inflammatory profiles in immune cells. This demonstrates the importance of using relevant stimuli when targeting the TLR7 pathway for therapeutic purposes.


Assuntos
Adenina/farmacologia , Complexo Antígeno-Anticorpo/farmacologia , Linfócitos B/imunologia , Células Dendríticas/imunologia , Complexos Multiproteicos/farmacologia , RNA/farmacologia , Receptor 7 Toll-Like/metabolismo , Adenina/análogos & derivados , Adenina/química , Complexo Antígeno-Anticorpo/química , Diferenciação Celular , Células Cultivadas , Citocinas/metabolismo , Perfilação da Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , Ativação Linfocitária , Estrutura Molecular , Complexos Multiproteicos/química , RNA/química , Receptor 7 Toll-Like/agonistas
7.
Proc Natl Acad Sci U S A ; 117(9): 4701-4709, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32079721

RESUMO

Proteins' interactions with ancient ligands may reveal how molecular recognition emerged and evolved. We explore how proteins recognize adenine: a planar rigid fragment found in the most common and ancient ligands. We have developed a computational pipeline that extracts protein-adenine complexes from the Protein Data Bank, structurally superimposes their adenine fragments, and detects the hydrogen bonds mediating the interaction. Our analysis extends the known motifs of protein-adenine interactions in the Watson-Crick edge of adenine and shows that all of adenine's edges may contribute to molecular recognition. We further show that, on the proteins' side, binding is often mediated by specific amino acid segments ("themes") that recur across different proteins, such that different proteins use the same themes when binding the same adenine-containing ligands. We identify numerous proteins that feature these themes and are thus likely to bind adenine-containing ligands. Our analysis suggests that adenine binding has emerged multiple times in evolution.


Assuntos
Adenina/metabolismo , Evolução Molecular , Simulação de Acoplamento Molecular/métodos , Conformação Proteica , Adenina/química , Sítios de Ligação , Ligação de Hidrogênio , Ligação Proteica , Análise de Sequência de Proteína/métodos , Software
8.
Nat Commun ; 11(1): 721, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024848

RESUMO

Myo-inositol hexakisphosphate (IP6) is a natural product known to inhibit vascular calcification (VC), but with limited potency and low plasma exposure following bolus administration. Here we report the design of a series of inositol phosphate analogs as crystallization inhibitors, among which 4,6-di-O-(methoxy-diethyleneglycol)-myo-inositol-1,2,3,5-tetrakis(phosphate), (OEG2)2-IP4, displays increased in vitro activity, as well as more favorable pharmacokinetic and safety profiles than IP6 after subcutaneous injection. (OEG2)2-IP4 potently stabilizes calciprotein particle (CPP) growth, consistently demonstrates low micromolar activity in different in vitro models of VC (i.e., human serum, primary cell cultures, and tissue explants), and largely abolishes the development of VC in rodent models, while not causing toxicity related to serum calcium chelation. The data suggest a mechanism of action independent of the etiology of VC, whereby (OEG2)2-IP4 disrupts the nucleation and growth of pathological calcification.


Assuntos
Fosfatos de Inositol/química , Fosfatos de Inositol/farmacologia , Calcificação Vascular/tratamento farmacológico , 6-Fitase/metabolismo , Adenina/efeitos adversos , Animais , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos/métodos , Difusão Dinâmica da Luz , Etilenoglicol/química , Humanos , Injeções Subcutâneas , Fosfatos de Inositol/farmacocinética , Masculino , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Ratos Sprague-Dawley , Uremia/tratamento farmacológico , Uremia/fisiopatologia , Calcificação Vascular/induzido quimicamente , Difração de Raios X
9.
PLoS One ; 15(1): e0224875, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31995556

RESUMO

INTRODUCTION: Guidelines advocate the treatment of HCV in all HIV/HCV co-infected individuals. The aim of this randomized, open-label study (ClinicalTrials.gov identifier: NCT02707601; https://clinicaltrials.gov/ct2/show/NCT02707601) was to evaluate the safety/efficacy of ledipasvir/sofosbuvir (LDV/SOF) co-administered with elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) or rilpivirine/F/TAF (R/F/TAF) in HIV-1/HCV co-infected participants. METHODS: Participants with HIV-1 RNA <50 copies/mL and chronic HCV-genotype (GT) 1 (HCV treatment-naïve ± compensated cirrhosis or HCV treatment-experienced non-cirrhotic) were randomized 1:1 to switch to E/C/F/TAF or R/F/TAF. If HIV suppression was maintained at Week 8, participants received 12 weeks of LDV/SOF. The primary endpoint was sustained HCV virologic response 12 weeks after LDV/SOF completion (SVR12). RESULTS: Of 150 participants, 148 received ≥1 dose of HIV study drug and 144 received LDV/SOF (72 in each F/TAF group; 83% GT1a, 94% HCV treatment-naïve, 12% cirrhotic). Overall, SVR12 was 97% (95% confidence interval: 93-99%). Black race did not affect SVR12. Of four participants not achieving SVR12, one had HCV relapse, one had HCV virologic non-response due to non-adherence, and two missed the post-HCV Week 12 visit. Of 148 participants, 96% receiving E/C/F/TAF and 95% receiving R/F/TAF maintained HIV suppression at Week 24; no HIV resistance was detected. No participant discontinued LDV/SOF or E/C/F/TAF due to adverse events; one participant discontinued R/F/TAF due to worsening of pre-existing hypercholesterolemia. Renal toxicity was not observed in either F/TAF regimen during LDV/SOF co-administration. In conclusion, high rates of HCV SVR12 and maintenance of HIV suppression were achieved with LDV/SOF and F/TAF-based regimens. CONCLUSION: This study supports LDV/SOF co-administered with an F/TAF-based regimen in HIV-1/HCV-GT1 co-infected patients.


Assuntos
Coinfecção/tratamento farmacológico , Combinação de Medicamentos , Infecções por HIV/tratamento farmacológico , Hepatite C/tratamento farmacológico , Adenina/administração & dosagem , Adenina/análogos & derivados , Adulto , Idoso , Benzimidazóis/administração & dosagem , Coinfecção/virologia , Farmacorresistência Viral/efeitos dos fármacos , Emtricitabina/administração & dosagem , Feminino , Fluorenos/administração & dosagem , Infecções por HIV/complicações , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/patogenicidade , Hepacivirus/patogenicidade , Hepatite C/complicações , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/isolamento & purificação , Sofosbuvir/administração & dosagem , Tenofovir/administração & dosagem
11.
Anal Bioanal Chem ; 412(6): 1243-1249, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31897555

RESUMO

Inadequate adherence to chronic medications is a far-reaching problem with financial and human health consequences. By a wide margin, non-adherence is the leading cause of therapeutic failures of HIV pre-exposure chemoprophylaxis (PrEP) and antiretroviral therapy (ART). It has been proven that HIV infection can be prevented by daily dosing of emtricitabine and tenofovir disoproxil fumarate. Measurement of intracellular tenofovir diphosphate in red blood cells has been established as an effective way to assess cumulative adherence, however, the LC-MS-based analytical method developed for the purpose is both complicated and expensive. Here, we report a simple method for adherence monitoring based on direct MS quantification of intracellular tenofovir diphosphate in human whole blood. The method requires only microliters of whole blood, employs special membranes to perform plasma separation and concomitant desalting during blood collection, and uses nanoelectrospray on a triple quadrupole instrument. Quantitative performance in this proof-of-concept study includes RSDs of < 15% and successful analysis of a small number of patient samples with medium to high adherence levels. The results correlate with those of a validated LC-MS/MS method, and an R2 value of 0.9962 is achieved. This methodology has promise for extension to point-of-care testing using miniature mass spectrometers. Graphical abstract.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/sangue , Organofosfatos/sangue , Espectrometria de Massas em Tandem/métodos , Adenina/sangue , Adenina/normas , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/normas , Cromatografia Líquida/métodos , Humanos , Organofosfatos/normas , Estudo de Prova de Conceito , Padrões de Referência
12.
BMC Bioinformatics ; 21(1): 31, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996134

RESUMO

BACKGROUND: The analysis and comparison of RNA m6A methylation profiles have become increasingly important for understanding the post-transcriptional regulations of gene expression. However, current m6A profiles in public databases are not readily intercomparable, where heterogeneous profiles from the same experimental report but different cell types showed unwanted high correlations. RESULTS: Several normalizing or correcting methods were tested to remove such laboratory bias. And m6Acorr, an effective pipeline for correcting m6A profiles, was presented on the basis of quantile normalization and empirical Bayes batch regression method. m6Acorr could efficiently correct laboratory bias in the simulated dataset and real m6A profiles in public databases. The preservation of biological signals was examined after correction, and m6Acorr was found to better preserve differential methylation signals, m6A regulated targets, and m6A-related biological features than alternative methods. Finally, the m6Acorr server was established. This server could eliminate the potential laboratory bias in m6A methylation profiles and perform profile-profile comparisons and functional analysis of hyper- (hypo-) methylated genes based on corrected methylation profiles. CONCLUSION: m6Acorr was established to correct the existing laboratory bias in RNA m6A methylation profiles and perform profile comparisons on the corrected datasets. The m6Acorr server is available at http://www.rnanut.net/m6Acorr. A stand-alone version with the correction function is also available in GitHub at https://github.com/emersON106/m6Acorr.


Assuntos
Adenina/análogos & derivados , RNA/metabolismo , Software , Adenina/metabolismo , Animais , Teorema de Bayes , Humanos , Internet , Masculino , Metilação , Camundongos , RNA/química , Processamento Pós-Transcricional do RNA
13.
DNA Cell Biol ; 39(3): 368-378, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31971825

RESUMO

Nuclear protein 1 (NUPR1) is a stress-related small molecule and plays important roles in various tumors, including multiple myeloma (MM). Autophagy is essential for maintaining cellular homoeostasis in response to stress and, together with apoptosis, determines cell fate. Previous studies indicate that NUPR1 is involved in cancer progression of MM, but the underlying mechanisms have not been elucidated. In this study, we confirmed that NUPR1 and basal autophagy markers were highly expressed in the bone marrow of MM patients. The overexpression of NUPR1 was correlated with staging (both by Revised International Staging System [RISS] and Durie-Salmon [D-S] Staging System), levels of hemoglobin and calcium, and bone marrow plasma cell ratio in the MM patients. NUPR1 silencing reduced autophagy activities and induced apoptosis in U266 and RPMI 8226. We further observed a decrease in NUPR1 silencing-induced apoptosis in the presence of rapamycin, while an increase in apoptosis after chloroquine and 3-methyladenine treatment. Analysis of the mechanism indicated that PI3K/AKT/mTOR pathway was involved in autophagy-mediated apoptosis upon NUPR1 knockdown. In summary, our results demonstrate that NUPR1 silencing suppresses autophagy activities and induces autophagy-mediated apoptosis in MM cells through the PI3K/AKT/mTOR pathway, which exhibits potential as a treatment strategy for MM.


Assuntos
Apoptose , Autofagia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Mieloma Múltiplo/metabolismo , Proteínas de Neoplasias/genética , Transdução de Sinais , Adenina/análogos & derivados , Adenina/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Linhagem Celular Tumoral , Cloroquina/farmacologia , Inativação Gênica , Humanos , Mieloma Múltiplo/genética , Proteínas de Neoplasias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo
14.
Phys Chem Chem Phys ; 22(5): 2999-3007, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31957771

RESUMO

Infrared multiple photon dissociation (IRMPD) spectroscopy has been used to probe the structures of the three protonated base-pair mismatches containing 9-ethylguanine (9eG) in the gas phase. Computational chemistry has been used to determine the relative energies and compute the infrared spectra of these complexes. By comparing the IRMPD spectra with the computed spectra, in all cases, it was possible to deduce that what was observed experimentally were the lowest energy computed structures. The protonated complex between 9eG and 1-methylthymine (1mT) is protonated at N7 of 9eG-the most basic site of all three bases in this study-and bound in a Hoogsteen type structure with two hydrogen bonds. The experimental IRMPD spectrum for the protonated complex between 9eG and 9-methyladenine (9mA) is described as arising from a combination of the two lowest energy structures, both which are protonated at N1 of adenine and each containing two hydrogen bonds with 9eG being the acceptor of both. The protonated dimer of 9eG is protonated at N7 with an N7-H+-N7 ionic hydrogen bond. It also contains an interaction between a C-H of protonated guanine and the O6 carbonyl of neutral guanine which is manifested in a slight red shift of that carbonyl stretch. The protonated 9eG/9mA structures have been previously identified by X-ray crystallography in RNA and are contained within the protein database.


Assuntos
Gases/química , Guanina/análogos & derivados , Espectrofotometria Infravermelho , Adenina/análogos & derivados , Adenina/química , Adenina/metabolismo , Pareamento Incorreto de Bases , Cristalografia por Raios X , Guanina/química , Guanina/metabolismo , Ligação de Hidrogênio , Modelos Moleculares , Fótons , Timina/análogos & derivados , Timina/química , Timina/metabolismo
15.
J Chem Phys ; 152(3): 035101, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31968979

RESUMO

One-electron oxidation of adenine (A) leads initially to the formation of adenine radical cation (A•+). Subsequent deprotonation of A•+ can provoke deoxyribonucleic acid (DNA) damage, which further causes senescence, cancer formation, and even cell death. However, compared with considerable reports on A•+ reactions in free deoxyadenosine (dA) and duplex DNA, studies in non-B-form DNA that play critical biological roles are rare at present. It is thus of vital importance to explore non-B-form DNA, among which the triplex is an emerging topic. Herein, we investigate the deprotonation behavior of A•+ in the TAT triplex with continuous A bases by time-resolved laser flash photolysis. The rate constants for the one-oxidation of triplex 8.4 × 108 M-1 s-1 and A•+ deprotonation 1.3 × 107 s-1 are obtained. The kinetic isotope effect of A•+ deprotonation in the TAT triplex is 1.8, which is characteristic of a direct release of the proton into the solvent similar to free base dA. It is thus elucidated that the A•+ proton bound with the third strand is most likely to be released into the solvent because of the weaker Hoogsteen H-bonding interaction and the presence of the highly mobile hydration waters within the third strand. Additionally, it is confirmed through Fourier transform infrared spectroscopy that the deprotonation of A•+ results in the dissociation of the third strand and disruption of the secondary structure of the triplex. These results provide valuable kinetic data and in-depth mechanistic insights for understanding the adenine oxidative DNA damage in the triplex.


Assuntos
Adenina/química , DNA/química , Elétrons , Timina/química , Ligação de Hidrogênio , Oxirredução
16.
Nat Commun ; 11(1): 52, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31911608

RESUMO

Prostatic luminal epithelial cells secrete high levels of acetylated polyamines into the prostatic lumen, sensitizing them to perturbations of connected metabolic pathways. Enhanced flux is driven by spermidine/spermine N1-acetyltransferase (SSAT) activity, which acetylates polyamines leading to their secretion and drives biosynthetic demand. The methionine salvage pathway recycles one-carbon units lost to polyamine biosynthesis to the methionine cycle to overcome stress. Prostate cancer (CaP) relies on methylthioadenosine phosphorylase (MTAP), the rate-limiting enzyme, to relieve strain. Here, we show that inhibition of MTAP alongside SSAT upregulation is synergistic in androgen sensitive and castration recurrent CaP models in vitro and in vivo. The combination treatment increases apoptosis in radical prostatectomy ex vivo explant samples. This unique high metabolic flux through polyamine biosynthesis and connected one carbon metabolism in CaP creates a metabolic dependency. Enhancing this flux while simultaneously targeting this dependency in prostate cancer results in an effective therapeutic approach potentially translatable to the clinic.


Assuntos
Metionina/metabolismo , Poliaminas/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Acetiltransferases/genética , Acetiltransferases/metabolismo , Adenina/administração & dosagem , Adenina/análogos & derivados , Animais , Apoptose , Linhagem Celular Tumoral , Quimioterapia Combinada , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Purina-Núcleosídeo Fosforilase/genética , Purina-Núcleosídeo Fosforilase/metabolismo , Pirrolidinas/administração & dosagem , Terapia de Salvação , Espermina/administração & dosagem , Espermina/análogos & derivados , Espermina/metabolismo
17.
Chem Biol Interact ; 317: 108943, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31926917

RESUMO

Epidemiological studies have shown that cigarette smoking is beneficial in ulcerative colitis and that nicotine may be responsible for this effect. However, the mechanism remains unclear. In a previous study, nicotine was found to induce autophagy in intestinal cells. Here, we evaluated the effect of nicotine-induced autophagy in a dextran sodium sulfate (DSS)-induced colitis mouse model. C57BL/6 adult male mice drank DSS water solution freely for seven consecutive days, and then tap water was administered. The effect of nicotine treatment was examined in the DSS model, including colon length, disease severity, histology of the colon tissue, and inflammation levels. Moreover, autophagy levels were detected by Western blot analysis (LC3II/LC3I, p62, and beclin-1). The levels of DSS-induced colitis were significantly decreased following nicotine treatment. The disease activity score, body weight, histologic damage scores, and the level of colonic inflammatory factors of nicotine-treated mice all decreased compared to those of the control mice. Additionally, nicotine enhanced the expression of LC3II/LC3I and beclin-1 but decreased the p62 protein level. Inhibiting autophagy by 3-MA attenuated the protective effects of nicotine on colitis. Additionally, both in vitro and in vivo experiments showed changes in AMPK-mTOR-P70S6K during this process. These results suggest that nicotine improved colitis by regulating autophagy and provided a protective effect against DSS-induced colitis.


Assuntos
Adenilato Quinase/metabolismo , Autofagia/efeitos dos fármacos , Colite/prevenção & controle , Nicotina/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Adenina/análogos & derivados , Adenina/farmacologia , Adenilato Quinase/genética , Animais , Colite/induzido quimicamente , Sulfato de Dextrana/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Quinases S6 Ribossômicas 70-kDa/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Serina-Treonina Quinases TOR/genética
18.
Nat Biomed Eng ; 4(1): 97-110, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31937940

RESUMO

The success of base editors for the study and treatment of genetic diseases depends on the ability to deliver them in vivo to the relevant cell types. Delivery via adeno-associated viruses (AAVs) is limited by AAV packaging capacity, which precludes the use of full-length base editors. Here, we report the application of dual AAVs for the delivery of split cytosine and adenine base editors that are then reconstituted by trans-splicing inteins. Optimized dual AAVs enable in vivo base editing at therapeutically relevant efficiencies and dosages in the mouse brain (up to 59% of unsorted cortical tissue), liver (38%), retina (38%), heart (20%) and skeletal muscle (9%). We also show that base editing corrects, in mouse brain tissue, a mutation that causes Niemann-Pick disease type C (a neurodegenerative ataxia), slowing down neurodegeneration and increasing lifespan. The optimized delivery vectors should facilitate the efficient introduction of targeted point mutations into multiple tissues of therapeutic interest.


Assuntos
Adenina/metabolismo , Citosina/metabolismo , Dependovirus/fisiologia , Edição de Genes/métodos , Animais , Encéfalo/metabolismo , Vetores Genéticos/administração & dosagem , Células HEK293 , Humanos , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Retina/metabolismo
19.
Expert Opin Pharmacother ; 21(4): 389-397, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31957507

RESUMO

Introduction: Antiretroviral therapy (ART) is recommended for all people who are living with HIV to suppress viral load and to stop the progression and transmission of HIV-1. Fixed-dose combinations of antiretrovirals largely reduce pill burden.Areas covered: The authors first provide an overview of the use of non-nucleoside reverse transcriptase inhibitor (NNRTI) based therapy in HIV care. They then summarize the properties of each drug in the fixed-dose combination of tenofovir alafenamide/emtricitabine/rilpivirine/(TAF/FTC/RPV). The efficacy and safety of each component and the combination as a whole are reviewed: FTC is non-inferior to lamivudine (3TC) at assessed dosages; TAF was non-inferior to tenofovir disoproxil fumarate (TDF); the viral efficacy of RPV is non-inferior with EFV at the assessed dosage; TAF/FTC/RPV is non-inferior in efficacy but shows less of a decline in bone mineral density and renal function compared to TDF/FTC/RPV. Finally, adverse effects and drug-drug interaction data with FTC/RPV/TAF are discussed.Expert opinion: TAF/FTC/RPV can be used as an initial regimen for people living with HIV whose HIV RNA <100,000 copies/ml and CD4 cell count > 200 cells/mm3 when INSTI-based regimens are not a treatment option. Future antiretroviral therapy development may focus on dual therapy-based regimens containing RPV, particularly as long-acting formulations.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/uso terapêutico , Emtricitabina/uso terapêutico , Infecções por HIV/tratamento farmacológico , Rilpivirina/uso terapêutico , Adenina/administração & dosagem , Adenina/efeitos adversos , Adenina/uso terapêutico , Adulto , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/efeitos adversos , Contagem de Linfócito CD4 , Combinação de Medicamentos , Emtricitabina/administração & dosagem , Emtricitabina/efeitos adversos , Feminino , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Humanos , Rilpivirina/administração & dosagem , Rilpivirina/efeitos adversos , Carga Viral
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