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1.
Antioxidants (Basel) ; 13(2)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38397802

RESUMO

Studies in the field have actively pursued the incorporation of diverse biological functionalities into gadolinium-based contrast agents, aiming at the amalgamation of MRI imaging and therapeutic capabilities. In this research, we present the development of Gd-Ga, an anti-neuroinflammatory MR contrast agent strategically designed to target inflammatory mediators for comprehensive imaging diagnosis and targeted lesion treatment. Gd-Ga is a gadolinium complex composed of 1,4,7-tris(carboxymethylaza)cyclododecane-10-azaacetylamide (DO3A) conjugated with gallic acid (3,4,5-trihydroxybenzoic acid). Upon intravenous administration in LPS-induced mouse models, Gd-Ga demonstrated a remarkable three-fold increase in signal-to-noise (SNR) variation compared to Gd-DOTA, particularly evident in both the cortex and hippocampus 30 min post-MR monitoring. In-depth investigations, both in vitro and in vivo, into the anti-neuroinflammatory properties of Gd-Ga revealed significantly reduced protein expression levels of pro-inflammatory mediators compared to the LPS group. The alignment between in silico predictions and phantom studies indicates that Gd-Ga acts as an anti-neuroinflammatory agent by directly binding to MD2. Additionally, the robust antioxidant activity of Gd-Ga was confirmed by its effective scavenging of NO and ROS. Our collective findings emphasize the immense potential of this theranostic complex, where a polyphenol serves as an anti-inflammatory drug, presenting an exceptionally efficient platform for the diagnosis and treatment of neuroinflammation.

2.
Int J Mol Sci ; 24(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37047841

RESUMO

Studies have been actively conducted to ensure that gadolinium-based contrast agents for magnetic resonance imaging (MRI) are accompanied by various biological functions. A new example is the anti-inflammatory theragnostic MRI agent to target inflammatory mediators for imaging diagnosis and to treat inflammatory diseases simultaneously. We designed, synthesized, and characterized a Gd complex of 1,4,7-tris(carboxymethylaza) cyclododecane-10-azaacetylamide (DO3A) conjugated with a nonsteroidal anti-inflammatory drug (NSAID) that exerts the innate therapeutic effect of NSAIDs and is also applicable in MRI diagnostics. Gd-DO3A-fen (0.1 mmol/kg) was intravenously injected into the turpentine oil-induced mouse model, with Gd-DO3A-BT as a control group. In the in vivo MRI experiment, the contrast-to-noise ratio (CNR) was higher and persisted longer than that with Gd-DO3A-BT; specifically, the CNR difference was almost five times at 2 h after injection. Gd-DO3A-fen had a binding affinity (Ka) of 6.68 × 106 M-1 for the COX-2 enzyme, which was 2.1-fold higher than that of fenbufen, the original NSAID. In vivo evaluation of anti-inflammatory activity was performed in two animal models. In the turpentine oil-induced model, the mRNA expression levels of inflammatory parameters such as COX-2, TNF-α, IL-1ß, and IL-6 were reduced, and in the carrageenan-induced edema model, swelling was suppressed by 72% and there was a 2.88-fold inhibition compared with the saline group. Correlation analysis between in vitro, in silico, and in vivo studies revealed that Gd-DO3A-fen acts as an anti-inflammatory theragnostic agent by directly binding to COX-2.


Assuntos
Compostos Organometálicos , Animais , Camundongos , Compostos Organometálicos/química , Gadolínio/química , Ciclo-Oxigenase 2/genética , Terebintina , Meios de Contraste/química , Imageamento por Ressonância Magnética/métodos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios não Esteroides/farmacologia
3.
Pharmaceuticals (Basel) ; 15(6)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35745670

RESUMO

Here, we describe the synthesis, characterization, and in vitro biological evaluation of a series of transition metal complexes containing benzothiazole aniline (BTA). We employed BTA, which is known for its selective anticancer activity, and a salen-type Schiff-based ligand to coordinate several transition metals to achieve selective and synergistic cytotoxicity. The compounds obtained were characterized by NMR spectroscopy, mass spectrometry, Fourier transform infrared spectroscopy, and elemental analysis. The compounds L, MnL, FeL, CoL, and ZnL showed promising in vitro cytotoxicity against cancer cells, and they had a lower IC50 than that of the clinically used cisplatin. In particular, MnL had synergistic cytotoxicity against liver, breast, and colon cancer cells. Moreover, MnL, CoL, and CuL promoted the production of reactive oxygen species in HepG2 tumor cell lines. The lead compound of this series, MnL, remained stable in physiological settings, and docking results showed that it interacted rationally with the minor groove of DNA. Therefore, MnL may serve as a viable alternative to platinum-based chemotherapy.

4.
J Enzyme Inhib Med Chem ; 37(1): 1257-1277, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35484863

RESUMO

Identification of highly selective type II kinase inhibitors is described. Two different chiral peptidomimetic scaffolds were introduced on the tail region of non-selective type II kinase inhibitor GNF-7 to enhance the selectivity. Kinome-wide selectivity profiling analysis showed that type II kinase inhibitor 7a potently inhibited Lck kinase with great selectivity (IC50 of 23.0 nM). It was found that 7a and its derivatives possessed high selectivity for Lck over even structurally conserved all Src family kinases. We also observed that 7a inhibited Lck activation in Jurkat T cells. Moreover, 7a was found to alleviate clinical symptoms in DSS-induced colitis mice. This study provides a novel insight into the design of selective type II kinase inhibitors by adopting chiral peptidomimetic moieties on the tail region.


Assuntos
Peptidomiméticos , Animais , Proteína Tirosina Quinase p56(lck) Linfócito-Específica , Camundongos , Peptidomiméticos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Quinases da Família src
5.
Cancers (Basel) ; 14(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35454900

RESUMO

Hepatocellular carcinomas (HCCs) are aggressive tumors with a poor prognosis. Approved first-line treatments include sorafenib, lenvatinib, and a combination of atezolizumab and bevacizumab; however, they do not cure HCC. We investigated MBP-11901 as a drug candidate for HCC. Cell proliferation and cytotoxicity were evaluated using normal and cancer human liver cell lines, while Western blotting and flow cytometry evaluated apoptosis. The anticancer effect of MBP-11901 was verified in vitro through migration, invasion, colony formation, and JC-1 MMP assays. In mouse models, the tumor volume, tumor weight, and bodyweight were measured, and cancer cell proliferation and apoptosis were analyzed. The toxicity of MBP-11901 was investigated through GOT/GPT and histological analyses in the liver and kidney. The signaling mechanism of MBP-11901 was investigated through kinase assays, phosphorylation analysis, and in silico docking simulations. Results. MBP-11901 was effective against various human HCC cell lines, leading to the disappearance of most tumors when administered orally in animal models. This effect was dose-dependent, with no differences in efficacy according to administration intervals. MBP-11901 induced anticancer effects by targeting the signaling mechanisms of FLT3, VEGFR2, c-KIT, and PDGFRß. MBP-11901 is suggested as a novel therapeutic agent for the treatment of advanced or unresectable liver cancer.

6.
J Med Chem ; 65(8): 6313-6324, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35418226

RESUMO

The purpose of this study is to assess the physicochemical properties and MRI diagnostic efficacy of two newly synthesized 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-type Gd chelates, Gd-SucL and Gd-GluL, with an asymmetric α-substituted pendant arm as potential hepatocyte-specific magnetic resonance imaging contrast agents (MRI CAs). Our findings show that fine conformational changes in the chelating arm affect the in vivo pharmacokinetic behavior of the MRI CA, and that a six-membered chelating substituent of Gd-SucL is more advantageous in this system to avoid unwanted interactions with endogenous species. Gd-SucL exhibited a general DOTA-like chelate stability trend, indicating that all chelating arms retain coordination bonding. Finally, the in vivo diagnostic efficacy of highly stable Gd-SucL as a potential hepatocyte-specific MRI CA was evaluated using T1-weighted MR imaging on an orthotopic hepatocarcinoma model.


Assuntos
Meios de Contraste , Gadolínio , Ânions , Quelantes/química , Meios de Contraste/química , Gadolínio/química , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
7.
Cancer Res Treat ; 54(3): 937-949, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34607396

RESUMO

PURPOSE: Melanoma incidence is rising worldwide along with the associated personal and socioeconomic health expenditures. We investigated the incidence and survival-rate patterns of melanoma in South Korea using nationwide data. MATERIALS AND METHODS: This retrospective cohort study included patients with melanoma between 2004 and 2017, based on National Health Insurance (NHI) claims data in South Korea. The incidence, prevalence, and survival rate were analyzed along with baseline demographic characteristics. We collected solar irradiation dose (SID) and healthcare ranking score (HRS) according to the administrative district from the Korea Meteorological Administration and Korea Health Promotion Institute. The incidence and survival rates were assessed using Pearson's correlation, the Kaplan-Meier estimation, multiple linear regression, and multiple logistic regression methods. RESULTS: Twenty-five thousand, five hundred ninety-one patients with melanoma were diagnosed during the study period. The age-standardized incidence of melanoma steadily increased from 2004 to 2017 from 2.6 to 3.0/100,000/yr. The incidence of melanoma increased with significantly higher income (p < 0.05). The prevalence followed a similar pattern as the incidence. According to multivariate analysis, HRS significantly influenced the incidence of melanoma in high sun-exposed sites (p < 0.001). There was no significant change in annual mortality. Women had a higher 5-year survival rate than men (78.4% vs. 72.8%). Mortality by the administrative district was highly correlated with HRS. CONCLUSION: The incidence of melanoma is increasing in South Korea. A low HRS is associated with both higher incidence and mortality. The findings of this study could be utilized as a guideline for treating melanoma patients.


Assuntos
Melanoma , Neoplasias Cutâneas , Feminino , Humanos , Incidência , Seguro Saúde , Masculino , Melanoma/epidemiologia , República da Coreia/epidemiologia , Estudos Retrospectivos , Neoplasias Cutâneas/epidemiologia , Taxa de Sobrevida , Melanoma Maligno Cutâneo
8.
Medicina (Kaunas) ; 57(9)2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34577854

RESUMO

Backgroundand Objectives: Aspirin is used globally to reduce pain and inflammation; however, its effect in patients with coronavirus disease (COVID-19) is not fully investigated and remains controversial. We evaluated the association between aspirin and COVID-19 outcomes using nationwide data from the Korean National Health Insurance System. Materials and Methods: This was a retrospective observational cohort study that included 22,660 eligible patients who underwent COVID-19 testing in South Korea between 1 January-31 July 2020. We identified all aspirin users prescribed aspirin within two weeks before or after the index date. The primary outcome was positivity for the COVID-19 test, and secondary outcomes included conventional oxygen therapy, intensive care unit, mechanical ventilation, or death. We applied the propensity score matching method to reduce the possible bias originating from the differences in patients' baseline characteristics. Results: Of those eligible, 662 patients were prescribed aspirin. Among them, 136 patients were on aspirin within two weeks before diagnosis and 526 patients were on aspirin after diagnosis. The COVID-19 test positivity rate was not significantly different according to aspirin use. Aspirin use before COVID-19 was related to an increased death rate and aspirin use after COVID-19 was related to a higher risk of the conventional oxygen therapy. Conclusion: Aspirin use was associated with adverse effects in COVID-19 patients. Further studies for mechanisms are needed.


Assuntos
Aspirina , COVID-19 , Aspirina/efeitos adversos , Teste para COVID-19 , Estudos de Coortes , Humanos , SARS-CoV-2
9.
Pharmaceuticals (Basel) ; 14(8)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34451928

RESUMO

We describe the synthesis, characterization, molecular modeling, and in vitro anticancer activity of three benzothiazole aniline (BTA) ligands and their corresponding platinum (II) complexes. We designed the compounds based on the selective antitumor properties of BTA, along with three types of metallic centers, aiming to take advantage of the distinctive and synergistic activity of the complexes to develop anticancer agents. The compounds were characterized using nuclear magnetic resonance spectrometry, Fourier transform infrared spectroscopy, mass spectrometry, elemental analysis, and tested for antiproliferative activity against multiple normal and cancerous cell lines. L1, L2, and L1Pt had better cytotoxicity in the liver, breast, lung, prostate, kidney, and brain cells than clinically used cisplatin. Especially, L1 and L1Pt demonstrated selective inhibitory activities against liver cancer cells. Therefore, these compounds can be a promising alternative to the present chemotherapy drugs.

10.
Neurology ; 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34031201

RESUMO

ObjectiveTo test the genetic contribution of rare missense variants in COL4A1 and COL4A2 in which common variants are genetically associated with sporadic intracerebral hemorrhage (ICH), we performed rare variant analysis in multiple sequencing data for the risk for sporadic ICH.MethodsWe performed sequencing across 559Kbp at 13q34 including COL4A1 and COL4A2 among 2,133 individuals (1,055 ICH cases; 1,078 controls) in US-based and 1,492 individuals (192 ICH cases; 1,189 controls) from Scotland-based cohorts, followed by sequence annotation, functional impact prediction, genetic association testing, and in silico thermodynamic modeling.ResultsWe identified 107 rare nonsynonymous variants in sporadic ICH, of which two missense variants, rs138269346 (COL4A1I110T) and rs201716258 (COL4A2H203L), were predicted to be highly functional and occurred in multiple ICH cases but not in controls from the US-based cohort. The minor allele of rs201716258 was also present in Scottish ICH patients, and rs138269346 was observed in two ICH-free controls with a history of hypertension and myocardial infarction. Rs138269346 was nominally associated with non-lobar ICH risk (P=0.05), but not with lobar ICH (P=0.08), while associations between rs201716258 and ICH subtypes were non-significant (P>0.12). Both variants were considered pathogenic based on minor allele frequency (<0.00035 in EUR), predicted functional impact (deleterious or probably damaging), and in silico modeling studies (substantially altered physical length and thermal stability of collagen).ConclusionsWe identified rare missense variants in COL4A1/A2 in association with sporadic ICH. Our annotation and simulation studies suggest that these variants are highly functional and may represent targets for translational follow-up.

11.
J Chem Inf Model ; 61(1): 36-45, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33252229

RESUMO

Following identification of a target protein, hit identification, which finds small organic molecules that bind to the target, is an important first step of a structure-based drug design project. In this study, we demonstrate a target-specific drug design method that can autonomously generate a series of target-favorable compounds. This method utilizes the seq2seq model based on a deep learning algorithm and a water pharmacophore. Water pharmacophore models are used to screen compounds that are favorable to a given target in a large compound database, and seq2seq compound generators are used to train the screened compounds and generate entirely new compounds based on the training model. Our method was tested through binding energy calculation studies of six pharmaceutically relevant targets in the directory of useful decoys (DUD) set with docking. The compounds generated by our method had lower average binding energies than decoy compounds in five out of six cases and included a number of compounds that had lower binding energies than the average binding energies of the active compounds in four cases. The generated compound lists for these four cases featured compounds with lower binding energies than even the most active compounds.


Assuntos
Aprendizado Profundo , Desenho de Fármacos , Algoritmos , Ligantes , Simulação de Acoplamento Molecular , Proteínas , Água
12.
ACS Med Chem Lett ; 11(8): 1529-1534, 2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32832019

RESUMO

G protein-coupled receptors (GPCRs) have always been important drug targets in the pharmaceutical industry. One major question for the current GPCR drug discovery is how drugs have distinct efficacies at the same GPCR target. Related to this question, we studied how different ligands can have disparate efficacies at Leukotriene B4 receptor (BLT2). By using molecular modeling studies, we predicted that Tyr2716.51 located at TM6 of BLT2 performs as a key trigger for its activation and verified the prediction by site-directed mutagenesis, chemotactic motility studies, which included a chemical derivative of agonist CAY10583. We further identified Asn2756.55 located at TM6 as a weak activation trigger in BLT2 and performed double mutation studies to confirm our computational results. Our results provide strong evidence for the exact mechanism of ligand efficacy at BLT2.

13.
J Med Chem ; 63(13): 6909-6923, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32545964

RESUMO

Advancements in recanalization therapies have rendered reperfusion injury an important challenge for stroke management. It is essential to work toward effective therapeutics that protect the ischemic brain from reperfusion injury. Here, we report a new concept of neuroprognostic agents, which combine molecular diagnostic imaging and targeted neuroprotection for treatment of reperfusion injury after stroke. These neuroprognostic agents are inflammation-targeted gadolinium compounds conjugated with nonsteroidal anti-inflammatory drugs (NSAIDs). Our results demonstrated that gadolinium-based MRI contrast agents conjugated with NSAIDs suppressed the increase in cyclooxygenase-2 (COX-2) levels, ameliorated glial activation, and neuron damage that are phenotypic for stroke by mitigating neuroinflammation, which prevented reperfusion injury. In addition, this study showed that the neuroprognostic agents are promising T1 molecular MRI contrast agents for detecting precise reperfusion injury locations at the molecular level. Our results build on this new concept of neuroprognostics as a novel management strategy for ischemia-reperfusion injury, combining neuroprotection and molecular diagnostics.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Gadolínio/química , Imageamento por Ressonância Magnética , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/prevenção & controle , Acidente Vascular Cerebral/complicações , Animais , Anti-Inflamatórios não Esteroides/química , Meios de Contraste/química , Ciclo-Oxigenase 2/química , Masculino , Simulação de Acoplamento Molecular , Fármacos Neuroprotetores/química , Conformação Proteica , Ratos , Ratos Sprague-Dawley
14.
Biomaterials ; 243: 119939, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32182490

RESUMO

High sensitivity at ultra-high field (UHF) and sufficient potential to penetrate the brain are the most desirable characteristics in the development of contrast agents (CAs) for magnetic resonance imaging (MRI). However, incorporating such qualities into a single nanocarrier is challenging. Herein, we report a new strategy for a highly brain-permeable MR CA with high sensitivity at UHF by loading dysprosium chelates (DyL) in apoferritin cavities (Apo-DyL). We also design the chelate ligand structure to increase DyL loading capacity within the apoferritin cavity. Using the intracerebroventricular (ICV) injection approach as a new delivery route for Apo-DyL, we demonstrate that apoferritin loaded with DyL can penetrate the brain-ventricular barrier and diffuse into the brain. This brain-permeable capability is unique to Apo-DyL, compared with other types of nanoparticles used in MRI. Apo-DyL also shows significant increase in MR sensitivity of DyL at UHF. Furthermore, based on brain tumor imaging at UHF, Apo-DyL can significantly enhance the tumor for a lower dose of the CA than the previously reported Gd- or Mn-loaded apoferritin nanoplatform. Therefore, Apo-DyL can be a novel nanoplatform that is a highly sensitive and versatile MR CA for UHF brain imaging.


Assuntos
Apoferritinas , Meios de Contraste , Encéfalo/diagnóstico por imagem , Disprósio , Imageamento por Ressonância Magnética
15.
Int J Biol Macromol ; 155: 439-446, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32220643

RESUMO

Ionic liquids (ILs) are known to provide stability to biomolecules. ILs are also widely used in the fields of chemical engineering, biological engineering, chemistry, and biochemistry because they facilitate enzyme catalyzed reactions and enhance their conversion rate. In this work, we have evaluated the influence of alkyl chain substitution of ammonium ILs such as diethylammonium dihydrogen phosphate (DEAP) and triethylammonium hydrogen phosphate (TEAP) for the stability and activity of the tobacco etch virus (TEV) protease. Further, we performed molecular dynamics (MD) simulations to calculate the RMSD (root mean square deviation) for TEV and TEV + ILs. Experimental and simulations results show that TEV is more stable in the presence of TEAP than DEAP. Whereas, TEV protease activity for the cleavage of fusion proteins is preserved in the presence of DEAP while lost in the presence of TEAP. Hence, DEAP IL can serve as alternative solvents for the stability of the TEV protease with preserved activity. To the best of our knowledge, this is first study to show that ILs can stabilize and maintain the TEV protease cleavage activity.


Assuntos
Compostos de Amônio/química , Endopeptidases/química , Endopeptidases/metabolismo , Líquidos Iônicos/química , Estabilidade Enzimática , Modelos Moleculares , Simulação de Dinâmica Molecular , Conformação Proteica , Solventes/química
16.
Appl Radiat Isot ; 156: 109015, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32056693

RESUMO

For evaluating the counting efficiency of a portal monitor, we use a137Cs radiation point source (1 µCi) to subsequently establish it effective measurable area. Through simulation, we estimate the appropriate distance from potentially contaminated individuals in the scanning queue to the monitoring individual. When this distance is over 10 m, the counting efficiency was below 0.01%. We find that the triage can be applied to roughly 180 individuals per hour during mass casualties.


Assuntos
Radioisótopos de Césio/análise , Incidentes com Feridos em Massa , Contagem de Cintilação/métodos , Triagem/métodos , Humanos , Monitoramento de Radiação/métodos
17.
J Mol Graph Model ; 92: 208-215, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31394427

RESUMO

When intracellular reactive oxygen species (ROS) increase, cancer cells are more vulnerable to oxidative stress compared to normal cells; thus, the collapse of redox homeostasis can lead to selective death of cancer cells. Indeed, recent studies have shown that inhibition of sulfiredoxin (Srx), which participates in antioxidant mechanisms, induces ROS-mediated cancer cell death. In this paper, we describe how an Srx inhibitor, J14 (4-[[[4-[4-(2-chlor-ophenyl)-1-piperazinyl]-6-phenyl-2-pyrimidinyl]thio]methyl]-benzoic acid), interferes with the antioxidant activity of Srx at the molecular level. We searched for possible binding sites of Srx using a binding site prediction method and uncovered two possible inhibition mechanisms of Srx by J14. Using molecular dynamics simulations and binding free energy calculations, we confirmed that J14 binds to the ATP binding site; therefore, J14 acts as a competitive inhibitor of ATP, settling the question of the two mechanisms. Based on the inhibition mechanism revealed at the atomic level, we designed several derivatives of J14, which led to LMT-328 (4-(((4-(4-(2-Chlorophenyl)piperazin-1-yl)-6-(2,4-dihydroxy-5-isopropylphenyl)pyrimidin-2-yl)thio)methyl)benzoic acid), which is possibly an even more potent inhibitor than J14.


Assuntos
Antioxidantes/química , Inibidores Enzimáticos/química , Modelos Moleculares , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/química , Trifosfato de Adenosina/química , Antioxidantes/farmacologia , Sítios de Ligação , Catálise , Inibidores Enzimáticos/farmacologia , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/antagonistas & inibidores , Ligação Proteica , Espécies Reativas de Oxigênio/química , Relação Estrutura-Atividade
18.
Bioconjug Chem ; 29(11): 3614-3625, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30383368

RESUMO

In this study, we designed and synthesized a highly stable manganese (Mn2+)-based hepatobiliary complex by tethering an ethoxybenzyl (EOB) moiety with an ethylenediaminetetraacetic acid (EDTA) coordination cage as an alternative to the well-established hepatobiliary gadolinium (Gd3+) chelates and evaluated its usage as a T1 hepatobiliary magnetic resonance imaging (MRI) contrast agent (CA). This new complex exhibits higher r1 relaxivity (2.3 mM-1 s-1) than clinically approved Mn2+-based hepatobiliary complex Mn-DPDP (1.6 mM-1 s-1) at 1.5 T. Mn-EDTA-EOB shows much higher kinetic inertness than that of clinically approved Gd3+-based hepatobiliary MRI CAs, such as Gd-DTPA-EOB and Gd-BOPTA. In addition, in vivo biodistribution and MRI enhancement patterns of this new Mn2+ chelate are comparable to those of Gd3+-based hepatobiliary MRI CAs. The diagnostic efficacy of the new complex was demonstrated by its enhanced tumor detection sensitivity in a liver cancer model using in vivo MRI.


Assuntos
Sistema Biliar/diagnóstico por imagem , Meios de Contraste/síntese química , Ácido Edético/química , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Manganês/química , Animais , Linhagem Celular , Quelantes/química , Quelantes/farmacocinética , Meios de Contraste/química , Ácido Edético/farmacocinética , Feminino , Gadolínio DTPA/química , Xenoenxertos , Humanos , Concentração de Íons de Hidrogênio , Cinética , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Simulação de Acoplamento Molecular , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas de Bombardeamento Rápido de Átomos
19.
Sci Rep ; 8(1): 10400, 2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-29991756

RESUMO

In this study, we demonstrate a method to construct a water-based pharmacophore model which can be utilized in the absence of known ligands. This method utilizes waters found in the binding pocket, sampled through molecular dynamics. Screening of compound databases against this water-based pharmacophore model reveals that this approach can successfully identify known binders to a target protein. The method was tested by enrichment studies of 7 therapeutically important targets and compared favourably to screening-by-docking with Glide. Our results suggest that even without experimentally known binders, pharmacophore models can be generated using molecular dynamics with waters and used for virtual screening.


Assuntos
Ensaios de Triagem em Larga Escala , Simulação de Dinâmica Molecular , Conformação Proteica , Água/química , Acetilcolinesterase/química , Biotina/química , Domínio Catalítico , Inibidores Enzimáticos/química , Humanos , Ligantes , Simulação de Acoplamento Molecular , Ligação Proteica , Receptores Androgênicos/química , Estreptavidina/química , Interface Usuário-Computador
20.
Exp Mol Med ; 49(11): e402, 2017 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-29170475

RESUMO

Recently, single-nucleotide polymorphisms (SNPs) in G-protein-coupled receptors (GPCRs) have been suggested to contribute to physiopathology and therapeutic effects. Leukotriene B4 receptor 2 (BLT2), a member of the GPCR family, plays a critical role in the pathogenesis of several inflammatory diseases, including cancer and asthma. However, no studies on BLT2 SNP effects have been reported to date. In this study, we demonstrate that the BLT2 SNP (rs1950504, Asp196Gly), a Gly-196 variant of BLT2 (BLT2 D196G), causes enhanced cell motility under low-dose stimulation of its ligands. In addition, we demonstrated that Akt activation and subsequent production of reactive oxygen species (ROS), both of which act downstream of BLT2, are also increased by BLT2 D196G in response to low-dose ligand stimulation. Furthermore, we observed that the ligand binding affinity of BLT2 D196G was enhanced compared with that of BLT2. Through homology modeling analysis, it was predicted that BLT2 D196G loses ionic interaction with R197, potentially resulting in increased agonist-receptor interaction. To the best of our knowledge, this report is the first to describe a SNP study on BLT2 and shows that BLT2 D196G enhances ligand sensitivity, thereby increasing cell motility in response to low-dose ligand stimulation.


Assuntos
Movimento Celular/genética , Polimorfismo de Nucleotídeo Único , Receptores do Leucotrieno B4/genética , Alelos , Animais , Células CHO , Quimiotaxia/genética , Cricetulus , Genótipo , Humanos , Leucotrieno B4/química , Leucotrieno B4/metabolismo , Ligantes , Modelos Moleculares , Conformação Molecular , Fases de Leitura Aberta , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores do Leucotrieno B4/química , Receptores do Leucotrieno B4/metabolismo , Transdução de Sinais
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