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1.
Amino Acids ; 55(12): 1729-1743, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37517044

RESUMO

Adenosine deaminase (ADA) is a Zn2+-containing enzyme that catalyzes the irreversible deamination of adenosine to inosine or deoxyadenosine to deoxyinosine. In addition to this enzymatic function, ADA mediates cell-to-cell interactions involved in lymphocyte co-stimulation or endothelial activation. ADA is implicated in cardiovascular pathologies such as atherosclerosis and certain types of cancers, including lymphoma and leukemia. To date, only two drugs (pentostatin and cladribine) have been approved for the treatment of hairy cell leukemia. In search of natural ADA inhibitors, we demonstrated the binding of selected phenolic compounds to the active site of ADA using molecular docking and molecular dynamics simulation. Our results show that phenolic compounds (chlorogenic acid, quercetin, and hyperoside) stabilized the ADA complex by forming persistent interactions with the catalytically essential Zn2+ ion. Furthermore, MM-GBSA ligand binding affinity calculations revealed that hyperoside had a comparable binding energy score (ΔG = - 46.56 ± 8.26 kcal/mol) to that of the cocrystal ligand in the ADA crystal structure (PDB ID: 1O5R) (ΔG = - 51.97 ± 4.70 kcal/mol). Similarly, chlorogenic acid exhibited a binding energy score (ΔG = - 18.76 ± 4.60 kcal/mol) comparable to those of the two approved ADA inhibitor drugs pentostatin (ΔG = - 14.54 ± 2.25 kcal/mol) and cladribine (ΔG = - 25.52 ± 4.10 kcal/mol) while quercetin was found to have modest binding affinity (ΔG = - 8.85 ± 7.32 kcal/mol). This study provides insights into the possible inhibitory potential of these phenolic compounds against ADA.


Assuntos
Inibidores de Adenosina Desaminase , Pentostatina , Inibidores de Adenosina Desaminase/farmacologia , Inibidores de Adenosina Desaminase/química , Simulação de Acoplamento Molecular , Quercetina/farmacologia , Cladribina , Ligantes , Ácido Clorogênico , Simulação de Dinâmica Molecular
2.
J Biomol Struct Dyn ; 41(2): 377-385, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34851227

RESUMO

Adenosine deaminase is a zinc+2 dependent key enzyme of purine metabolism which irreversibly converts adenosine to inosine and form ammonia. Overexpression of adenosine deaminase has been linked to a variety of pathophysiological conditions such as atherosclerosis, hypertension, and diabetes. In the case of a cell-mediated immune response, ADA is thought to be a marker, particularly in type II diabetes. Deoxycoformycin is the most potent ADA inhibitor that has been discovered so far, but it has several drawbacks, including being toxic and having poor pharmacokinetics. Taxifolin, a flavonoid derived from plants, was discovered to be a potent inhibitor of the human ADA (hADA) enzyme in the current study. Taxifolin bound at the active site of human ADA and showed fifty percent inhibition at a concentration of 400 µM against the enzyme. To better understand the interactions between taxifolin and human ADA, docking and molecular dynamic simulations were performed. In-silico studies using autodock revealed that taxifolin bound in the active site of human ADA with a binding energy of -7.4 kcal mol -1 and a theoretical Ki of 3.7 uM. Comparative analysis indicated that taxifolin and deoxycoformycin share a common binding space in the active site of human ADA and inhibit its catalytic activity similarly. The work emphasises the need of employing taxifolin as a lead chemical in order to produce a more precise and effective inhibitor of the human ADA enzyme with therapeutic potential.Communicated by Ramaswamy H. Sarma.


Assuntos
Adenosina Desaminase , Diabetes Mellitus Tipo 2 , Humanos , Adenosina Desaminase/química , Adenosina Desaminase/metabolismo , Pentostatina/farmacologia , Inibidores de Adenosina Desaminase/farmacologia , Inibidores de Adenosina Desaminase/química
3.
J Biomol Struct Dyn ; 40(11): 5112-5127, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-33397209

RESUMO

Novel coronavirus (COVID-19) responsible for viral pneumonia which emerged in late 2019 has badly affected the world. No clinically proven drugs are available yet as the targeted therapeutic agents for the treatment of this disease. The viral main protease which helps in replication and transcription inside the host can be an effective drug target. In the present study, we aimed to discover the potential of ß-adrenoceptor agonists and adenosine deaminase inhibitors which are used in asthma and cancer/inflammatory disorders, respectively, as repurposing drugs against protease inhibitor by ligand-based and structure-based virtual screening using COVID-19 protease-N3 complex. The AARRR pharmacophore model was used to screen a set of 22,621 molecules to obtain hits, which were subjected to high-throughput virtual screening. Extra precision docking identified four top-scored molecules such as +/--fenoterol, FR236913 and FR230513 with lower binding energy from both categories. Docking identified three major hydrogen bonds with Gly143, Glu166 and Gln189 residues. 100 ns MD simulation was performed for four top-scored molecules to analyze the stability, molecular mechanism and energy requirements. MM/PBSA energy calculation suggested that van der Waals and electrostatic energy components are the main reasons for the stability of complexes. Water-mediated hydrogen bonds between protein-ligand and flexibility of the ligand are found to be responsible for providing extra stability to the complexes. The insights gained from this combinatorial approach can be used to design more potent and bio-available protease inhibitors against novel coronavirus.Communicated by Ramaswamy H. Sarma.


Assuntos
Inibidores de Adenosina Desaminase , Agonistas Adrenérgicos , Antivirais , Proteases 3C de Coronavírus , SARS-CoV-2 , Inibidores de Adenosina Desaminase/química , Inibidores de Adenosina Desaminase/farmacologia , Agonistas Adrenérgicos/química , Agonistas Adrenérgicos/farmacologia , Antivirais/química , Antivirais/farmacologia , Proteases 3C de Coronavírus/antagonistas & inibidores , Reposicionamento de Medicamentos , Humanos , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Receptores Adrenérgicos , SARS-CoV-2/efeitos dos fármacos , Tratamento Farmacológico da COVID-19
4.
Bioorg Med Chem ; 43: 116272, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34157570

RESUMO

Inhibitors of the enzyme adenosine monophosphate deaminase (AMPD) show interesting levels of herbicidal activity. An enzyme mechanism-based approach has been used to design new inhibitors of AMPD starting from nebularine (6) and resulting in the synthesis of 2-deoxy isonebularine (16). This compound is a potent inhibitor of the related enzyme adenosine deaminase (ADA; IC50 16 nM), binding over 5000 times more strongly than nebularine. It is proposed that the herbicidal activity of compound 16 is due to 5́-phosphorylation in planta to give an inhibitor of AMPD. Subsequently, an enzyme structure-based approach was used to design new non-ribosyl AMPD inhibitors. The initial lead structure was discovered by in silico screening of a virtual library against plant AMPD. In a second step, binding to AMPD was further optimised via more detailed molecular modeling leading to 2-(benzyloxy)-5-(imidazo[2,1-f][1,2,4]triazin-7-yl)benzoic acid (36) (IC50 300 nM). This compound does not inhibit ADA and shows excellent selectivity for plant over human AMPD.


Assuntos
AMP Desaminase/antagonistas & inibidores , Inibidores de Adenosina Desaminase/farmacologia , Adenosina Desaminase/metabolismo , Desenho de Fármacos , AMP Desaminase/metabolismo , Inibidores de Adenosina Desaminase/síntese química , Inibidores de Adenosina Desaminase/química , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
5.
ChemMedChem ; 15(22): 2151-2156, 2020 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-32729197

RESUMO

Adenosine deaminase (ADA) is a human mononuclear Zn2+ metalloenzyme that converts adenosine to inosine. ADA is a validated drug target for cancer, but there has been little recent work on the development of new therapeutics against this enzyme. The lack of new advancements can be partially attributed to an absence of suitable assays for high-throughput screening (HTS) against ADA. To facilitate more rapid drug discovery efforts for this target, an in vitro assay was developed that utilizes the enzymatic conversion of a visibly emitting adenosine analogue to the corresponding fluorescent inosine analogue by ADA, which can be monitored via fluorescence intensity changes. Utilizing this assay, a library of ∼350 small molecules containing metal-binding pharmacophores (MBPs) was screened in an HTS format to identify new inhibitor scaffolds against ADA. This approach yielded a new metal-binding scaffold with a Ki value of 26±1 µM.


Assuntos
Inibidores de Adenosina Desaminase/farmacologia , Adenosina Desaminase/metabolismo , Oxazóis/farmacologia , Zinco/farmacologia , Inibidores de Adenosina Desaminase/síntese química , Inibidores de Adenosina Desaminase/química , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Humanos , Estrutura Molecular , Oxazóis/química , Zinco/química
6.
J Recept Signal Transduct Res ; 40(1): 77-88, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31971048

RESUMO

Adenosine deaminase (ADA) is an enzyme present in purine metabolic pathway. Its inhibitors are considered to be potent drug lead compounds against inflammatory and malignant diseases. This study aimed to test ADA inhibitory activity of some Streptomyces secondary metabolites by using computational and in vitro methods. The in silico screening of the inhibitory properties has been carried out using pharmacophore modeling, docking, and molecular dynamics studies. The in vitro validation of the selected antibiotics has been carried out by enzyme kinetics and fluorescent spectroscopic studies. The results indicated that novobiocin, an aminocoumarin antibiotic from Streptomyces niveus, has significant inhibition on ADA activity. Hence, the antibiotic can be used as a lead compound for the development of potential ADA inhibitors.


Assuntos
Inibidores de Adenosina Desaminase/farmacologia , Adenosina Desaminase/metabolismo , Antibacterianos/farmacologia , Reposicionamento de Medicamentos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Streptomyces/química , Inibidores de Adenosina Desaminase/química , Aminoglicosídeos/química , Aminoglicosídeos/farmacologia , Domínio Catalítico , Avaliação Pré-Clínica de Medicamentos , Ensaios Enzimáticos , Humanos , Análise dos Mínimos Quadrados , Ligantes , Novobiocina/química , Novobiocina/farmacologia , Relação Quantitativa Estrutura-Atividade , Espectrometria de Fluorescência
7.
Biomed Chromatogr ; 34(3): e4779, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31845520

RESUMO

Cordycepin has recently received increased attention owing to its extensive pharmacological activity. Adenosine deaminase (ADA) is widely distributed in mammalian blood and tissues; as a result, cordycepin is quickly metabolized upon entering into the body and converted into the inactive metabolite 3'-deoxyinosine, thus limiting its activity when administered alone. We herein present a novel ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for screening ADA inhibitors against the metabolism of cordycepin. Cordycepin and 3'-deoxyinosine were chosen as substrate and product, respectively. A proper separation was achieved for all analytes within 3 min. 3'-Deoxyinosine was quantified in the presence or absence of potential ADA inhibitors to evaluate ADA activity. The assay can simultaneously determine substrate and product, with the endogenous substance and ADA inhibitors added not interfering in its activity. After optimizing the enzymatic incubation and UHPLC-MS/MS conditions, Km and Vmax values for ADA deamination of cordycepin were 95.18 ± 7.85 µm and 363.90 ± 12.16 µmol/min/unit, respectively. Oleanolic acid and ursolic acid from Ligustri Lucidi Fructus were chosen as ADA inhibitors with half maximal inhibitory concentration values of 21.82 ± 0.39 and 18.41 ± 0.14 µm, respectively. A non-competitive inhibition model was constructed and this assay can be used to screen other potential ADA inhibitors quickly and accurately.


Assuntos
Inibidores de Adenosina Desaminase , Cromatografia Líquida de Alta Pressão/métodos , Desoxiadenosinas , Ligustrum/química , Extratos Vegetais , Inibidores de Adenosina Desaminase/análise , Inibidores de Adenosina Desaminase/química , Inibidores de Adenosina Desaminase/isolamento & purificação , Desoxiadenosinas/análise , Desoxiadenosinas/metabolismo , Descoberta de Drogas , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Espectrometria de Massas em Tandem/métodos , Triterpenos , Ácido Ursólico
8.
Folia Microbiol (Praha) ; 65(2): 293-302, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31273645

RESUMO

Medicinal plants have been studied for potential endophytic interactions and numerous studies have provided evidence that seeds harbor diverse microbial communities, not only on their surfaces but also within the embryo. Adenosine deaminase (ADA) is known as a potential therapeutic target for the treatment of lymphoproliferative disorders and cancer. Therefore, in this study, 20 types of medicinal plant seeds were used to screen endophytic fungi with tissue homogenate and streak. In addition, 128 morphologically distinct endophyte strains were isolated and their ADA inhibitory activity determined by a spectrophotometric assay. The strain with the highest inhibitory activity was identified as Cochliobolus sp. Seven compounds were isolated from the strain using a chromatography method. Compound 3 showed the highest ADA inhibitory activity and was identified as 5-hydroxy-2-hydroxymethyl-4H-pyran-4-one, based on the results of 1H and 13C NMR spectroscopy. The results of molecular docking suggested that compound 3 binds to the active site and the nonspecific binding site of the ADA. Furthermore, we found that compound 3 is a mixed ADA inhibitor. These results indicate that endophytic strains are a promising source of ADA inhibitors and that compound 3 may be a superior source for use in the preparation of biologically active ADA inhibitor compounds used to treat cancer.


Assuntos
Inibidores de Adenosina Desaminase/química , Ascomicetos/química , Endófitos/química , Plantas Medicinais/microbiologia , Adenosina Desaminase/química , Adenosina Desaminase/metabolismo , Inibidores de Adenosina Desaminase/farmacologia , Ascomicetos/classificação , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Sítios de Ligação , Endófitos/classificação , Endófitos/genética , Endófitos/isolamento & purificação , Humanos , Espectroscopia de Ressonância Magnética , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Sementes/microbiologia
9.
Comput Biol Chem ; 83: 107111, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31445420

RESUMO

Epigallocatechin gallate, a flavonoid from Camellia sinensis possess various pharmacological activities such as anticancer, antimicrobial and antioxidant etc. Adenosine deaminase, (ADA), is a key enzyme involved in the purine metabolism, the inhibitors of which is being considered as highly promising candidate for the development of anti-proliferative and anti-inflammatory drugs. In this work we studied adenosine deaminase inhibitory activity of epigallocatechin gallate by using biophysical and computational methods. The enzyme inhibition study result indicated that epigallocatechin gallate possess strong inhibitory activity on ADA. ITC study revealed the energetics of binding. Also the binding is confirmed by using fluorescence spectroscopy. The structural details of binding are obtained from molecular docking and MD simulation studies.


Assuntos
Inibidores de Adenosina Desaminase/farmacologia , Adenosina Desaminase/metabolismo , Catequina/análogos & derivados , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores de Adenosina Desaminase/química , Calorimetria , Camellia sinensis/química , Catequina/química , Catequina/farmacologia , Humanos , Espectrometria de Fluorescência , Termodinâmica
10.
Sensors (Basel) ; 19(12)2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31216643

RESUMO

Adenosine deaminase (ADA), which catalyzes the irreversible deamination of adenosine to inosine, is related to various human diseases such as tuberculous peritonitis and leukemia. Therefore, the method used to detect ADA activity and screen the effectiveness of various inhibitor candidates has important implications for the diagnosis treatment for various human diseases. A simple and rapid assay method for ADA, based on the enzymatic formation of a luminescent lanthanide complex, is proposed in this study. Inosine, an enzymatic product of ADA with stronger sensitization efficiency for Tb3+ than adenosine, produced a strong luminescence by forming an inosine-Tb3+ complex, and it enabled the direct monitoring of ADA activity in real-time. By introducing only Tb3+ to adenosine and ADA in the buffer, the enhancement of luminescence enabled the detection of a low concentration of ADA (detection limit 1.6 U/L). Moreover, this method could accurately determine the inhibition efficiency (IC50) of the known ADA inhibitor, erhythro-9-(2-hydroxy-3-nonyl)adenine (EHNA), and the inhibition of ADA could be confirmed by the naked eye. Considering its simplicity, this assay could be extended to the high-throughput screening of various ADA inhibitor candidates.


Assuntos
Adenosina Desaminase/isolamento & purificação , Técnicas Biossensoriais , Complexos de Coordenação/química , Inosina/química , Adenosina/química , Adenosina Desaminase/química , Inibidores de Adenosina Desaminase/química , Humanos , Elementos da Série dos Lantanídeos/química
11.
Arch Biochem Biophys ; 667: 6-13, 2019 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-31002765

RESUMO

Plasmodium falciparum (Pf), a malarial pathogen, can only synthesize purine nucleotides employing a salvage pathway because it lacks de novo biosynthesis. Adenosine deaminase (ADA), one of the three purine salvage enzymes, catalyzes the irreversible hydrolytic deamination of adenosine to inosine, which is further converted to GMP and AMP for DNA/RNA production. In addition to adenosine conversion, Plasmodium ADA also catalyzes the conversion of 5'-methylthioadenosine, derived from polyamine biosynthesis, into 5'-methylthioinosine whereas the human enzyme is not capable of this function. Here we report the crystal structure of a surface engineered PfADA at a resolution of 2.48 Å, together with results on kinetic studies of PfADA wild-type and active site variants. The structure reveals a novel inosine binding pocket linked to a distinctive PfADA substructure (residues 172-179) derived from a non-conserved gating helix loop (172-188) in Plasmodium spp. and other ADA enzymes. Variants of PfADA and human (h) ADA active site amino acids were generated in order to study their role in catalysis, including PfADA- Phe136, -Thr174, -Asp176, and -Leu179, and hADA-Met155, equivalent to PfADA-Asp176. PfADA-Leu179His showed no effect on kinetic parameters. However, kinetic results of PfADA-Asp176Met/Ala mutants and hADA-Met155Asp/Ala showed that the mutation reduced adenosine and 5'-methylthioadenosine substrate affinity in PfADA and kcat in hADA, thereby reducing catalytic efficiency of the enzyme. Phe136Leu mutant showed increased Km (>10-fold) for both substrates whereas Thr174Ile/Ala only affected 5'-methylthioadenosine binding affinity. Together, the structure with the novel inosine binding pocket and the kinetic data provide insights for rational design of inhibitors against PfADA.


Assuntos
Adenosina Desaminase/química , Plasmodium falciparum/enzimologia , Proteínas de Protozoários/química , Adenosina Desaminase/genética , Adenosina Desaminase/metabolismo , Inibidores de Adenosina Desaminase/química , Inibidores de Adenosina Desaminase/farmacologia , Sequência de Aminoácidos , Substituição de Aminoácidos , Domínio Catalítico , Cristalografia por Raios X , Desenho de Fármacos , Humanos , Inosina/metabolismo , Cinética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
12.
PLoS One ; 13(11): e0207234, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30444912

RESUMO

Adenosine deaminase (ADA) catalyzes the deamination of adenosine, which is important in purine metabolism. ADA is ubiquitous to almost all human tissues, and ADA abnormalities have been reported in various diseases, including rheumatoid arthritis. ADA can be divided into two conformations based on the inhibitor that it binds to: open and closed forms. Here, we chose three ligands, namely, FR117016 (FR0), FR221647 (FR2) (open form), and HDPR (PRH, closed form), to investigate the inhibition mechanism of ADA and its effect on ADA through molecular dynamics simulations. In open forms, Egap and electrostatic potential (ESP) indicated that electron transfer might occur more easily in FR0 than in FR2. Binding free energy and hydrogen bond occupation revealed that the ADA-FR0 complex had a more stable structure than ADA-FR2. The probability of residues Pro159 to Lys171 of ADA-FR0 and ADA-FR2 to form a helix moderately increased compared with that in nonligated ADA. In comparison with FR0 and FR2 PRH could maintain ADA in a closed form to inhibit the function of ADA. The α7 helix (residues Thr57 to Ala73) of ADA in the closed form was mostly unfastened because of the effect of PRH. The number of H bonds and the relative superiority of the binding free energy indicated that the binding strength of PRH to ADA was significantly lower than that of an open inhibitor, thereby supporting the comparison of the inhibitory activities of the three ligands. Alanine scanning results showed that His17, Gly184, Asp295, and Asp296 exerted the greatest effects on protein energy, suggesting that they played crucial roles in binding to inhibitors. This study served as a theoretical basis for the development of new ADA inhibitors.


Assuntos
Inibidores de Adenosina Desaminase/farmacologia , Adenosina Desaminase/química , Adenosina Desaminase/genética , Adenosina Desaminase/metabolismo , Inibidores de Adenosina Desaminase/química , Sítios de Ligação/genética , Estabilidade Enzimática , Humanos , Ligação de Hidrogênio , Cinética , Ligantes , Simulação de Dinâmica Molecular , Mutagênese Sítio-Dirigida , Análise de Componente Principal , Conformação Proteica , Conformação Proteica em alfa-Hélice , Teoria Quântica , Eletricidade Estática
13.
J Recept Signal Transduct Res ; 38(3): 240-245, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29843562

RESUMO

Adenosine deaminase (ADA) is one of the major enzymes involved in purin metabolism, it has a significant role in cell growth and differentiation. Over-activity of ADA has been noticed in some pathology, like malignancy and inflammation and makes it an attractive target for the development of drugs for such diseases. In the present study, ADA inhibitory activity of morin, a bioactive flavonoid, was assessed through computational and biophysical methods. The enzyme kinetics data showed that morin is a competitive inhibitor of ADA. Binding energy calculated from ITC analysis was -7.11 kcal/mol. Interaction of morin with ADA was also studied using fluorescence quenching method. Molecular docking studies revealed the structural details of the interaction. Molecular dynamics study in explicit solvent was also conducted to assess the structural stability of protein ligand complex.


Assuntos
Inibidores de Adenosina Desaminase/química , Adenosina Desaminase/química , Flavonoides/química , Adenosina Desaminase/efeitos dos fármacos , Adenosina Desaminase/metabolismo , Inibidores de Adenosina Desaminase/uso terapêutico , Sítios de Ligação/efeitos dos fármacos , Flavonoides/uso terapêutico , Humanos , Inflamação/tratamento farmacológico , Cinética , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Complexos Multiproteicos/química
14.
Cell Mol Biol (Noisy-le-grand) ; 64(3): 97-102, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29506637

RESUMO

Breast cancer is a heterogeneous and multifactorial disease with variable disease progression risk, and treatment response. Urtica dioica is a traditional herb used as an adjuvant therapeutic agent in cancer. In the present study, we have evaluated the effects of the aqueous extract of Urtica dioica on Adenosine deaminase (ADA) and Ornithine decarboxylase (ODC1) gene expression in MCF-7, MDA-MB-231, two breast cancer cell lines being estrogen receptor positive and estrogen receptor negative, respectively.  Cell lines were cultured in suitable media. After 24 h, different concentrations of the extract were added and after 72 h, ADA and ODC1 gene expression as well as BCL2 and BAX apoptotic genes were assessed by Taqman real time PCR assay. Cells viability was assessed by MTT assay, and apoptosis was also evaluated at cellular level. The intra and extracellular levels of ODC1 and ADA enzymes were evaluated by ELISA. Results showed differential expression of ADA and ODC1 genes in cancer cell lines. In MCF-7 cell line, the expression level of ADA was upregulated in a dose-dependent manner but its expression did not change in MDA-MB cell line. ODC1 expression was increased in both examined cell lines. Also, increased level of the apoptotic BAX/BCL-2 ratio was detected in MCF-7 cells. These results demonstrated that Urtica dioica induces apoptosis in breast cancer cells by influencing ODC1 and ADA genes expression, and estrogen receptors. The different responses observed with these cell lines could be due to the interaction of Urtica dioica as a phytoestrogen with the estrogen receptor.


Assuntos
Inibidores de Adenosina Desaminase/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Inibidores da Ornitina Descarboxilase/farmacologia , Urtica dioica/química , Adenosina/metabolismo , Adenosina Desaminase/metabolismo , Inibidores de Adenosina Desaminase/química , Antineoplásicos Fitogênicos/química , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Ornitina Descarboxilase/metabolismo , Inibidores da Ornitina Descarboxilase/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Poliaminas/metabolismo
15.
J Pharm Biomed Anal ; 153: 175-181, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29499460

RESUMO

Adenosine deaminase (ADA), which is a key enzyme in the metabolism of purine nucleosides, plays important roles in diverse disorders, such as tuberculosis, diabetes, liver disorders, and cancer. Determination of the activities of ADA and its isoenzymes in body fluids has received considerable attention in the diagnosis and treatment of relative diseases. Ultraviolet spectroscopy with adenosine (AD) as a substrate is a classical approach for screening potential ADA inhibitors by measuring the decrease in substrate (AD) at 265 nm or increase in the product (inosine) at 248 nm. However, AD and inosine share a very close maximum absorption wavelength, and the reaction is uncertain and is frequently interfered by the background color of matrix compounds or plant extracts. Thus, the method usually yields false positive or negative results. In this study, a novel, rapid, sensitive, and accurate ultra-high-performance liquid chromatography-Q exactive hybrid quadrupole orbitrap high-resolution accurate mass spectrometric (UHPLC-Q-Orbitrap HRMS) method was developed for determining and screening ADA inhibitors by directly determining the deamination product of AD, inosine. A proper separation was achieved for inosine and chlormequat (internal standard) within 2 min via isocratic elution (0.1% formic acid:methanol = 85:15, v/v) at a flow rate of 0.3 mL min-1 on a Waters ACQUITY HSS T3 column (2.1 mm × 100 mm, 1.8 µm) following a simple precipitation of proteins. The intra- and inter-day precisions of the developed method were below 7.17% and 8.99%, respectively. The method exhibited advantages of small total reaction volume (60 µL), short running time (2 min), high sensitivity (lowest limit of quantification of 0.02 µM for inosine), and low cost (small enzyme consumption of 0.007 unit mL-1 for ADA and substrate of 3.74 µM for AD in individual inhibition), and no matrix effects (101.64%-107.12%). Stability results showed that all analytes were stable under the investigated conditions. The developed method was successfully applied to the detection of the inhibitory activity of ADA from traditional Chinese medicines.


Assuntos
Inibidores de Adenosina Desaminase/química , Adenosina Desaminase/química , Extratos Vegetais/química , Líquidos Corporais/química , Clormequat/química , Cromatografia Líquida de Alta Pressão/métodos , Inosina/química , Limite de Detecção , Medicina Tradicional Chinesa/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/métodos
16.
Curr Microbiol ; 75(5): 565-573, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29243069

RESUMO

Adenosine deaminase (ADA) is an enzyme widely distributed from bacteria to humans. ADA is known as a potential therapeutic target for the treatment of lymphoproliferative disorders and cancer. Endophytes are endosymbionts, often bacteria or fungi, which live within plant tissues and internal organs or intercellular space. Endophytes have a broad variety of bioactive metabolites that are used for the identification of novel natural compounds. Here, 54 morphologically distinct endophyte strains were isolated from six plants such as Peganum harmala Linn., Rheum officinale Baill., Gentiana macrophylla Pall., Radix stephaniae tetrandrae, Myrrha, and Equisetum hyemale Linn. The isolated strains were used for the search of ADA inhibitors that resulted in the identification of the strain with the highest inhibition activity, Aspergillus niger sp. Four compounds were isolated from this strain using three-step chromatography procedure, and compound 2 was determined as the compound with the highest inhibition activity of ADA. Based on the results of 1H and 13C NMR spectroscopies, compound 2 was identified as 3-(4-nitrophenyl)-5-phenyl isoxazole. We showed that compound 2 was a new uncompetitive inhibitor of ADA with high cytotoxic effect on HepG2 and SMCC-7721 cells (the IC50 values were 0.347 and 0.380 mM, respectively). These results suggest that endophyte strains serve as promising sources for the identification of ADA inhibitors, and compound 2 could be an effective drug in the cancer treatment.


Assuntos
Inibidores de Adenosina Desaminase/química , Aspergillus niger/química , Endófitos/química , Plantas/microbiologia , Adenosina Desaminase/química , Adenosina Desaminase/metabolismo , Inibidores de Adenosina Desaminase/metabolismo , Aspergillus niger/genética , Aspergillus niger/isolamento & purificação , Aspergillus niger/metabolismo , Linhagem Celular , Endófitos/genética , Endófitos/isolamento & purificação , Endófitos/metabolismo , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular
17.
Biol Trace Elem Res ; 181(1): 164-172, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28429285

RESUMO

Poly-trans-[(2-carboxyethyl)germasesquioxane] (Ge-132) is a water-soluble organogermanium compound that exerts various physiological effects, including anti-inflammatory activity and pain relief. In water, Ge-132 is hydrolyzed to 3-(trihydroxygermyl)propanoic acid (THGP), which in turn is capable of interacting with cis-diol compounds through its trihydroxy group, indicating that this compound could also interact with diol-containing nucleic acid constituents. In this study, we evaluated the ability of THGP to interact with nucleosides or nucleotides via nuclear magnetic resonance (NMR) analysis. In addition, we evaluated the effect of added THGP on the enzymatic activity of adenosine deaminase (ADA) when using adenosine or 2'-deoxyadenosine as a substrate. In solution, THGP indeed formed complexes with nucleotides or nucleosides through their cis-diol group. Moreover, the ability of THGP to form complexes with nucleotides was influenced by the number of phosphate groups present on the ribose moiety. Notably, THGP also inhibited the catalysis of adenosine by ADA in a concentration-dependent manner. Thus, interactions between THGP and important biological nucleic acid constituents might be implicated in the physiological effects of Ge-132.


Assuntos
Inibidores de Adenosina Desaminase/farmacologia , Adenosina Desaminase/metabolismo , Adenosina/metabolismo , Ácidos Nucleicos/farmacologia , Compostos Organometálicos/farmacologia , Adenosina/análogos & derivados , Adenosina/química , Inibidores de Adenosina Desaminase/química , Biocatálise , Germânio , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Ácidos Nucleicos/química , Compostos Organometálicos/química , Propionatos , Espectrofotometria
18.
Bioorg Med Chem ; 25(20): 5799-5819, 2017 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-28951094

RESUMO

A series of terminal nonyl chain and nucleobase modified analogues of (+)-EHNA (III) were synthesized and evaluated for their ability to inhibit adenosine deaminase (ADA). The constrained carbon analogues of (+)-EHNA, 7a-7h, 10a-c, 12, 13, 14 and 17a-c appeared very potent with Ki values in the low nanomolar range. Thio-analogues of (+)-EHNA 24a-e wherein 5'C of nonyl chain replaced by sulfur atom found to be less potent compared to (+)-EHNA. Docking of the representative compounds into the active site of ADA was performed to understand structure-activity relationships. Compounds 7a (Ki: 1.1nM) 7b (Ki: 5.2nM) and 26a (Ki: 5.9nM) showed suitable balance of potency, microsomal stability and demonstrated better pharmacokinetic properties as compared to (+)-EHNA and therefore may have therapeutic potential for various inflammatory diseases, hypertension and cancer.


Assuntos
Adenina/análogos & derivados , Inibidores de Adenosina Desaminase/química , Adenina/síntese química , Adenina/química , Adenina/farmacocinética , Adenina/farmacologia , Inibidores de Adenosina Desaminase/síntese química , Inibidores de Adenosina Desaminase/farmacocinética , Inibidores de Adenosina Desaminase/farmacologia , Domínio Catalítico , Ativação Enzimática/efeitos dos fármacos , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
19.
Chem Pharm Bull (Tokyo) ; 63(2): 134-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25748785

RESUMO

A number of new 2,6-disubstituted-1-deazanebularine analogues as well as two structurally related pyrazole-fused tricyclic nucleosides were prepared. Their synthesis was carried out by the conversion of 6-amino-2-picoline to a suitable 1-deazapurine, followed by a Vorbrüggen type glycosylation and subsequent elaboration of the condensed pyrazole ring. The synthesized nebularine analogues proved to be weak adenosine deaminase inhibitors.


Assuntos
Inibidores de Adenosina Desaminase/síntese química , Adenosina Desaminase/química , Nucleosídeos de Purina/química , Ribonucleosídeos/química , Adenosina Desaminase/metabolismo , Inibidores de Adenosina Desaminase/química , Inibidores de Adenosina Desaminase/metabolismo , Animais , Bovinos , Glicosilação , Espectroscopia de Ressonância Magnética , Ligação Proteica , Nucleosídeos de Purina/síntese química , Nucleosídeos de Purina/metabolismo , Pirazóis/química , Ribonucleosídeos/síntese química , Ribonucleosídeos/metabolismo
20.
Inorg Chem ; 54(2): 434-40, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25531979

RESUMO

Two new silver(I) complexes of formula [Ag(mPTA)4](Tpms)4(BF4) (1) and [Ag(Tpms)(mPTA)](BF4) (2) (mPTA = N-methyl-1,3,5-triaza-7-phosphaadamantane cation, Tpms = tris(pyrazol-1-yl)methanesulfonate anion) have been synthesized and fully characterized by elemental analyses, (1)H and (31)P{(1)H} NMR, ESI-MS, and IR spectroscopic techniques. The single-crystal X-ray diffraction study of 1 discloses a noncoordinated nature of the Tpms species, existing as counterions around the highly charged metal center [Ag(mPTA)](5+), 1 being the first reported coordination compound bearing a κ(0)-Tpms. 1 features high solubility and stability in water (S25 °C ≈ 30 mg·mL(-1)). The two complexes interact with calf thymus DNA via intercalation mode, binding to the BSA with decrease of its tryptophan fluorescence with a static quenching mechanism. The two new silver complexes exhibit significant antibacterial and antifungal activities screened in vitro against the standard strains of Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans.


Assuntos
Adamantano/análogos & derivados , Luz , Compostos Organometálicos/síntese química , Compostos Organometálicos/farmacologia , Compostos Organofosforados/química , Prata/química , Água/química , Adamantano/química , Inibidores de Adenosina Desaminase/síntese química , Inibidores de Adenosina Desaminase/química , Inibidores de Adenosina Desaminase/metabolismo , Inibidores de Adenosina Desaminase/farmacologia , Animais , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Bovinos , Técnicas de Química Sintética , Estabilidade de Medicamentos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Molecular , Compostos Organometálicos/química , Compostos Organometálicos/metabolismo , Soroalbumina Bovina/metabolismo , Solubilidade
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