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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.
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.

3.
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.

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.
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
6.
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
7.
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.

8.
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
9.
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
10.
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
11.
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
12.
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
13.
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
14.
Sci Rep ; 7(1): 8698, 2017 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-28821765

RESUMO

Both gamma rays and atmospheric pressure plasma are known to have anticancer properties. While their mechanism actions are still not clear, in some contexts they work in similar manner, while in other contexts they work differently. So to understand these relationships, we have studied Myoglobin protein after the treatment of gamma rays and dielectric barrier discharge (DBD) plasma, and analyzed the changes in thermodynamic properties and changes in the secondary structure of protein after both treatments. The thermodynamic properties were analyzed using chemical and thermal denaturation after both treatments. We have also studied the action of gamma rays and DBD plasma on myoglobin in the presence of osmolytes, such as sorbitol and trehalose. For deep understanding of the action of gamma rays and DBD plasma, we have analyzed the reactive species generated by them in buffer at all treatment conditions. Finally, we have used molecular dynamic simulation to understand the hydrogen peroxide action on myoglobin with or without osmolytes, to gain deeper insight into how the osmolytes can protect the protein structure from the reactive species generated by gamma rays and DBD plasma.


Assuntos
Pressão Atmosférica , Raios gama , Mioglobina/química , Gases em Plasma/farmacologia , Substâncias Protetoras/farmacologia , Sorbitol/farmacologia , Trealose/farmacologia , Eletricidade , Humanos , Peróxido de Hidrogênio/toxicidade , Concentração de Íons de Hidrogênio , Simulação de Dinâmica Molecular , Desnaturação Proteica/efeitos dos fármacos , Desnaturação Proteica/efeitos da radiação , Estrutura Secundária de Proteína , Soluções , Ureia/farmacologia
15.
Phys Chem Chem Phys ; 19(37): 25277-25288, 2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28759059

RESUMO

Cold atmospheric plasma and gamma rays are known to have anticancer properties, even though their specific mechanisms and roles as co-solvents during their action are still not clearly understood. Despite the use of gamma rays in cancer therapy, they have oncogenic potential, whereas this has not been observed for plasma treatment (to date). To gain a better understanding, we studied the action of dielectric barrier discharge (DBD) plasma and gamma rays on the myoglobin protein. We analyzed the secondary structure and thermodynamic properties of myoglobin after both treatments. In addition, in the last few years, ammonium ionic liquids (ILs) have revealed their important role in protein folding as co-solvents. In this work, we treated the protein with ammonium ILs such as triethylammonium methanesulfonate (TEMS) and tetrabutylammonium methanesulfonate (TBMS) and later treated this IL-protein solution with DBD plasma and gamma rays. In this study, we show the chemical and thermal denaturation of the protein after plasma and gamma treatments in the presence and absence of ILs using circular dichroism (CD) and UV-vis spectroscopy. Furthermore, we also show the influence of plasma and gamma rays on the secondary structure of myoglobin in the absence and presence of ILs or ILs + urea using CD. Finally, molecular dynamic simulations were conducted to gain deeper insight into how the ILs behave to protect the protein against the hydrogen peroxide generated by the DBD plasma and gamma rays.


Assuntos
Raios gama , Líquidos Iônicos/química , Mioglobina/química , Estrutura Secundária de Proteína , Termodinâmica , Compostos de Amônio , Dicroísmo Circular , Temperatura Baixa , Íons , Simulação de Dinâmica Molecular , Gases em Plasma , Dobramento de Proteína
16.
Sci Rep ; 7(1): 2636, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28572671

RESUMO

Most cancer cells have telomerase activity because they can express the human telomerase reverse transcriptase (hTERT) gene. Therefore, the inhibition of the hTERT expression can play an important role in controlling cancer cell proliferation. Our current study aims to inhibit hTERT expression. For this, we synthesized graphene oxide (GO) and a functionalized multiwall carbon nanotube (f-MWCNT), latter treated them with cold atmospheric pressure plasma for further analysis of the hTERT expression. The inhibition of hTERT expression by GO, f-MWCNT, plasma activated GO solution (PGOS), and plasma activated f-MWCNT solution (PCNTS), was studied using two lung cancer cell lines, A549 and H460. The hTERT experimental results revealed that GO and PGOS sufficiently decreased the hTERT concentration, while f-MWCNT and PCNTS were unable to inhibit the hTERT concentration. Therefore, to understand the inhibition mechanism of hTERT, we studied the binding properties of GO and PGOS with telomere binding protein (AtTRB2). The interaction studies were carried out using circular dichroism, fluorescence, 1H-15N NMR spectroscopy, and size-exclusion chromatography (SEC) binding assay. We also used docking simulation to have an better understanding of the interactions between GO nanosheets and AtTRB2 protein. Our results may provide new insights that can benefit in biomedical treatments.


Assuntos
Nanotubos de Carbono/química , Plasma/química , Telomerase/antagonistas & inibidores , Proteínas de Ligação a Telômeros/farmacologia , Linhagem Celular Tumoral , Grafite/química , Grafite/farmacologia , Humanos , Simulação de Acoplamento Molecular , Nanoestruturas/química , Conformação Proteica , Telomerase/química , Proteínas de Ligação a Telômeros/química
17.
Sci Rep ; 6: 35883, 2016 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-27779212

RESUMO

Over the last few years, the variation in liquid chemistry due to the development of radicals generated by cold atmospheric plasma (CAP) has played an important role in plasma medicine. CAP direct treatment or CAP activated media treatment in cancer cells shows promising anticancer activity for both in vivo and in vitro studies. However, the anticancer activity or antimicrobial activity varies between plasma devices due to the different abilities among plasma devices to generate the reactive oxygen and nitrogen species (RONS) at different ratios and in different concentrations. While the generation of RONS depends on many factors, the feeding gas plays the most important role among the factors. Hence, in this study we used different compositions of feeding gas while fixing all other plasma characteristics. We used Ar, Ar-O2 (at different ratios), and Ar-N2 (at different ratios) as the working gases for CAP and investigated the structural changes in proteins (Hemoglobin (Hb) and Myoglobin (Mb)). We then analyzed the influence of RONS generated in liquid on the conformations of proteins. Additionally, to determine the influence of H2O2 on the Hb and Mb structures, we used molecular dynamic simulation.


Assuntos
Hemoglobinas/química , Hemoglobinas/metabolismo , Mioglobina/química , Mioglobina/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Gases em Plasma , Conformação Proteica
18.
Angew Chem Int Ed Engl ; 55(11): 3642-6, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26879524

RESUMO

Developing selective strategies to treat metastatic cancers remains a significant challenge. Herein, we report the first antibody-recruiting small molecule (ARM) that is capable of recognizing the urokinase-type plasminogen activator receptor (uPAR), a uniquely overexpressed cancer cell-surface marker, and facilitating the immune-mediated destruction of cancer cells. A co-crystal structure of the ARM-U2/uPAR complex was obtained, representing the first crystal structure of uPAR complexed with a non-peptide ligand. Finally, we demonstrated that ARM-U2 substantially suppresses tumor growth in vivo with no evidence of weight loss, unlike the standard-of-care agent doxorubicin. This work underscores the promise of antibody-recruiting molecules as immunotherapeutics for treating cancer.


Assuntos
Anticorpos/imunologia , Metástase Neoplásica/imunologia , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Cristalografia por Raios X , Humanos , Neoplasias/patologia
19.
J Chem Inf Model ; 52(12): 3278-83, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23194275

RESUMO

We used molecular dynamics (MD) simulations and protein docking to elucidate the mechanism of allosteric inhibition of the human form of peroxiredoxin (Prx), 2-Cys proliferation associated gene (PAG). Beginning by using the rat form of Prx, 2-Cys heme-binding protein as a template, we used homology modeling to find the structure of human 2-Cys PAG, which is in dimeric form. Molecular dynamics simulations showed that the structure of the reduced form of the 2-Cys PAG dimer fluctuates as the two monomers drift away and approach each other. We then used SiteMap to search for binding sites on the surface of this dimer. A binding site between the two monomers was found, and virtual screening with docking was performed to identify a ligand binding to this site. Subsequent MD simulation revealed that with this ligand in the binding site, the dimer structure of 2-Cys PAG becomes stabilized such that two cysteine residues from two monomers, which are partners of a disulfide bond of the oxidized form, remain separated. This mechanism can be used as an allosteric inhibition of Prx as a hydrogen peroxide reducer, the role of which has been studied as an anticancer drug target.


Assuntos
Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Peroxirredoxinas/antagonistas & inibidores , Peroxirredoxinas/química , Regulação Alostérica/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Sítios de Ligação , Descoberta de Drogas , Humanos , Dados de Sequência Molecular , Peroxirredoxinas/metabolismo , Conformação Proteica , Ratos , Termodinâmica
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