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1.
Amino Acids ; 55(12): 1729-1743, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37517044

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa , Pentostatina , Inhibidores de la Adenosina Desaminasa/farmacología , Inhibidores de la Adenosina Desaminasa/química , Simulación del Acoplamiento Molecular , Quercetina/farmacología , Cladribina , Ligandos , Ácido Clorogénico , Simulación de Dinámica Molecular
2.
J Biomol Struct Dyn ; 41(2): 377-385, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-34851227

RESUMEN

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.


Asunto(s)
Adenosina Desaminasa , Diabetes Mellitus Tipo 2 , Humanos , Adenosina Desaminasa/química , Adenosina Desaminasa/metabolismo , Pentostatina/farmacología , Inhibidores de la Adenosina Desaminasa/farmacología , Inhibidores de la Adenosina Desaminasa/química
3.
J Biomol Struct Dyn ; 40(11): 5112-5127, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-33397209

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa , Agonistas Adrenérgicos , Antivirales , Proteasas 3C de Coronavirus , SARS-CoV-2 , Inhibidores de la Adenosina Desaminasa/química , Inhibidores de la Adenosina Desaminasa/farmacología , Agonistas Adrenérgicos/química , Agonistas Adrenérgicos/farmacología , Antivirales/química , Antivirales/farmacología , Proteasas 3C de Coronavirus/antagonistas & inhibidores , Reposicionamiento de Medicamentos , Humanos , Ligandos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Inhibidores de Proteasas/química , Inhibidores de Proteasas/farmacología , Receptores Adrenérgicos , SARS-CoV-2/efectos de los fármacos , Tratamiento Farmacológico de COVID-19
4.
Bioorg Med Chem ; 43: 116272, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34157570

RESUMEN

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.


Asunto(s)
AMP Desaminasa/antagonistas & inhibidores , Inhibidores de la Adenosina Desaminasa/farmacología , Adenosina Desaminasa/metabolismo , Diseño de Fármacos , AMP Desaminasa/metabolismo , Inhibidores de la Adenosina Desaminasa/síntesis química , Inhibidores de la Adenosina Desaminasa/química , Relación Dosis-Respuesta a Droga , Humanos , Estructura Molecular , Relación Estructura-Actividad
5.
ChemMedChem ; 15(22): 2151-2156, 2020 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-32729197

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa/farmacología , Adenosina Desaminasa/metabolismo , Oxazoles/farmacología , Zinc/farmacología , Inhibidores de la Adenosina Desaminasa/síntesis química , Inhibidores de la Adenosina Desaminasa/química , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Humanos , Estructura Molecular , Oxazoles/química , Zinc/química
6.
J Recept Signal Transduct Res ; 40(1): 77-88, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31971048

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa/farmacología , Adenosina Desaminasa/metabolismo , Antibacterianos/farmacología , Reposicionamiento de Medicamentos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Streptomyces/química , Inhibidores de la Adenosina Desaminasa/química , Aminoglicósidos/química , Aminoglicósidos/farmacología , Dominio Catalítico , Evaluación Preclínica de Medicamentos , Pruebas de Enzimas , Humanos , Análisis de los Mínimos Cuadrados , Ligandos , Novobiocina/química , Novobiocina/farmacología , Relación Estructura-Actividad Cuantitativa , Espectrometría de Fluorescencia
7.
Folia Microbiol (Praha) ; 65(2): 293-302, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31273645

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa/química , Ascomicetos/química , Endófitos/química , Plantas Medicinales/microbiología , Adenosina Desaminasa/química , Adenosina Desaminasa/metabolismo , Inhibidores de la Adenosina Desaminasa/farmacología , Ascomicetos/clasificación , Ascomicetos/genética , Ascomicetos/aislamiento & purificación , Sitios de Unión , Endófitos/clasificación , Endófitos/genética , Endófitos/aislamiento & purificación , Humanos , Espectroscopía de Resonancia Magnética , Simulación del Acoplamiento Molecular , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Semillas/microbiología
8.
Biomed Chromatogr ; 34(3): e4779, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31845520

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa , Cromatografía Líquida de Alta Presión/métodos , Desoxiadenosinas , Ligustrum/química , Extractos Vegetales , Inhibidores de la Adenosina Desaminasa/análisis , Inhibidores de la Adenosina Desaminasa/química , Inhibidores de la Adenosina Desaminasa/aislamiento & purificación , Desoxiadenosinas/análisis , Desoxiadenosinas/metabolismo , Descubrimiento de Drogas , Extractos Vegetales/análisis , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Espectrometría de Masas en Tándem/métodos , Triterpenos , Ácido Ursólico
9.
Comput Biol Chem ; 83: 107111, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31445420

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa/farmacología , Adenosina Desaminasa/metabolismo , Catequina/análogos & derivados , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Inhibidores de la Adenosina Desaminasa/química , Calorimetría , Camellia sinensis/química , Catequina/química , Catequina/farmacología , Humanos , Espectrometría de Fluorescencia , Termodinámica
10.
Sensors (Basel) ; 19(12)2019 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-31216643

RESUMEN

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.


Asunto(s)
Adenosina Desaminasa/aislamiento & purificación , Técnicas Biosensibles , Complejos de Coordinación/química , Inosina/química , Adenosina/química , Adenosina Desaminasa/química , Inhibidores de la Adenosina Desaminasa/química , Humanos , Elementos de la Serie de los Lantanoides/química
11.
Arch Biochem Biophys ; 667: 6-13, 2019 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-31002765

RESUMEN

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.


Asunto(s)
Adenosina Desaminasa/química , Plasmodium falciparum/enzimología , Proteínas Protozoarias/química , Adenosina Desaminasa/genética , Adenosina Desaminasa/metabolismo , Inhibidores de la Adenosina Desaminasa/química , Inhibidores de la Adenosina Desaminasa/farmacología , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Dominio Catalítico , Cristalografía por Rayos X , Diseño de Fármacos , Humanos , Inosina/metabolismo , Cinética , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homología de Secuencia de Aminoácido , Especificidad por Sustrato
12.
PLoS One ; 13(11): e0207234, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30444912

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa/farmacología , Adenosina Desaminasa/química , Adenosina Desaminasa/genética , Adenosina Desaminasa/metabolismo , Inhibidores de la Adenosina Desaminasa/química , Sitios de Unión/genética , Estabilidad de Enzimas , Humanos , Enlace de Hidrógeno , Cinética , Ligandos , Simulación de Dinámica Molecular , Mutagénesis Sitio-Dirigida , Análisis de Componente Principal , Conformación Proteica , Conformación Proteica en Hélice alfa , Teoría Cuántica , Electricidad Estática
13.
J Recept Signal Transduct Res ; 38(3): 240-245, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29843562

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa/química , Adenosina Desaminasa/química , Flavonoides/química , Adenosina Desaminasa/efectos de los fármacos , Adenosina Desaminasa/metabolismo , Inhibidores de la Adenosina Desaminasa/uso terapéutico , Sitios de Unión/efectos de los fármacos , Flavonoides/uso terapéutico , Humanos , Inflamación/tratamiento farmacológico , Cinética , Ligandos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Complejos Multiproteicos/química
14.
Cell Mol Biol (Noisy-le-grand) ; 64(3): 97-102, 2018 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-29506637

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa/farmacología , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Inhibidores de la Ornitina Descarboxilasa/farmacología , Urtica dioica/química , Adenosina/metabolismo , Adenosina Desaminasa/metabolismo , Inhibidores de la Adenosina Desaminasa/química , Antineoplásicos Fitogénicos/química , Neoplasias de la Mama/metabolismo , Proliferación Celular/efectos de los fármacos , Femenino , Humanos , Células MCF-7 , Ornitina Descarboxilasa/metabolismo , Inhibidores de la Ornitina Descarboxilasa/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Poliaminas/metabolismo
15.
J Pharm Biomed Anal ; 153: 175-181, 2018 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-29499460

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa/química , Adenosina Desaminasa/química , Extractos Vegetales/química , Líquidos Corporales/química , Clormequat/química , Cromatografía Líquida de Alta Presión/métodos , Inosina/química , Límite de Detección , Medicina Tradicional China/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría de Masas en Tándem/métodos
16.
Biol Trace Elem Res ; 181(1): 164-172, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28429285

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa/farmacología , Adenosina Desaminasa/metabolismo , Adenosina/metabolismo , Ácidos Nucleicos/farmacología , Compuestos Organometálicos/farmacología , Adenosina/análogos & derivados , Adenosina/química , Inhibidores de la Adenosina Desaminasa/química , Biocatálisis , Germanio , Humanos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Ácidos Nucleicos/química , Compuestos Organometálicos/química , Propionatos , Espectrofotometría
17.
Curr Microbiol ; 75(5): 565-573, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29243069

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa/química , Aspergillus niger/química , Endófitos/química , Plantas/microbiología , Adenosina Desaminasa/química , Adenosina Desaminasa/metabolismo , Inhibidores de la Adenosina Desaminasa/metabolismo , Aspergillus niger/genética , Aspergillus niger/aislamiento & purificación , Aspergillus niger/metabolismo , Línea Celular , Endófitos/genética , Endófitos/aislamiento & purificación , Endófitos/metabolismo , Humanos , Espectroscopía de Resonancia Magnética , Estructura Molecular
18.
Bioorg Med Chem ; 25(20): 5799-5819, 2017 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-28951094

RESUMEN

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.


Asunto(s)
Adenina/análogos & derivados , Inhibidores de la Adenosina Desaminasa/química , Adenina/síntesis química , Adenina/química , Adenina/farmacocinética , Adenina/farmacología , Inhibidores de la Adenosina Desaminasa/síntesis química , Inhibidores de la Adenosina Desaminasa/farmacocinética , Inhibidores de la Adenosina Desaminasa/farmacología , Dominio Catalítico , Activación Enzimática/efectos de los fármacos , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad
19.
Chem Pharm Bull (Tokyo) ; 63(2): 134-42, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25748785

RESUMEN

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.


Asunto(s)
Inhibidores de la Adenosina Desaminasa/síntesis química , Adenosina Desaminasa/química , Nucleósidos de Purina/química , Ribonucleósidos/química , Adenosina Desaminasa/metabolismo , Inhibidores de la Adenosina Desaminasa/química , Inhibidores de la Adenosina Desaminasa/metabolismo , Animales , Bovinos , Glicosilación , Espectroscopía de Resonancia Magnética , Unión Proteica , Nucleósidos de Purina/síntesis química , Nucleósidos de Purina/metabolismo , Pirazoles/química , Ribonucleósidos/síntesis química , Ribonucleósidos/metabolismo
20.
Inorg Chem ; 54(2): 434-40, 2015 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-25531979

RESUMEN

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.


Asunto(s)
Adamantano/análogos & derivados , Luz , Compuestos Organometálicos/síntesis química , Compuestos Organometálicos/farmacología , Compuestos Organofosforados/química , Plata/química , Agua/química , Adamantano/química , Inhibidores de la Adenosina Desaminasa/síntesis química , Inhibidores de la Adenosina Desaminasa/química , Inhibidores de la Adenosina Desaminasa/metabolismo , Inhibidores de la Adenosina Desaminasa/farmacología , Animales , Antiinfecciosos/síntesis química , Antiinfecciosos/química , Antiinfecciosos/metabolismo , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Candida albicans/efectos de los fármacos , Bovinos , Técnicas de Química Sintética , Estabilidad de Medicamentos , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Conformación Molecular , Compuestos Organometálicos/química , Compuestos Organometálicos/metabolismo , Albúmina Sérica Bovina/metabolismo , Solubilidad
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