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Nerve agents are organophosphates (OPs) that act as potent inhibitors of acetylcholinesterase (AChE), the enzyme responsible for the hydrolysis of acetylcholine. After inhibition, a dealkylation reaction of the phosphorylated serine, known as the aging of AChE, can occur. When aged, reactivators of OP-inhibited AChE are no longer effective. Therefore, the realkylation of aged AChE may offer a pathway to reverse AChE aging. In this study, molecular modeling was conducted to propose new ligands as realkylators of aged AChE. We applied a methodology involving docking and quantum mechanics/molecular mechanics (QM/MM) calculations to evaluate the resurrection kinetic constants and ligand interactions with OP-aged AChE, comparing them to data found in the literature. The results obtained confirm that this method is suitable for predicting kinetic and thermodynamic parameters of ligands, which can be useful in the design and selection of new and more effective ligands for AChE realkylation.
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Acetilcolinesterasa , Inhibidores de la Colinesterasa , Indolquinonas , Acetilcolinesterasa/química , Acetilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Cinética , Indolquinonas/química , Simulación del Acoplamiento Molecular , Ligandos , Termodinámica , Modelos Moleculares , Humanos , Simulación de Dinámica MolecularRESUMEN
Early phase diagnosis of human diseases has still been a challenge in the medicinal field, and one of the efficient non-invasive techniques that is vastly used for this purpose is magnetic resonance imaging (MRI). MRI is able to detect a wide range of diseases and conditions, including nervous system disorders and cancer, and uses the principles of NMR relaxation to generate detailed internal images of the body. For such investigation, different metal complexes have been studied as potential MRI contrast agents. With this in mind, this work aims to investigate two systems containing the vanadium complexes [VO(metf)2]·H2O (VC1) and [VO(bpy)2Cl]+ (VC2), being metformin and bipyridine ligands of the respective complexes, with the biological targets AMPK and ULK1. These biomolecules are involved in the progression of Alzheimer's disease and triple-negative breast cancer, respectively, and may act as promising spectroscopic probes for detection of these diseases. To initially evaluate the behavior of the studied ligands within the aforementioned protein active sites and aqueous environment, four classical molecular dynamics (MD) simulations including VC1 + H2O (1), VC2 + H2O (2), VC1 + AMPK + H2O (3), and VC2 + ULK1 + H2O (4) were performed. From this, it was obtained that for both systems containing VCs and water only, the theoretical calculations implied a higher efficiency when compared with DOTAREM, a famous commercially available contrast agent for MRI. This result is maintained when evaluating the system containing VC1 + AMPK + H2O. Nevertheless, for the system VC2 + ULK1 + H2O, there was observed a decrease in the vanadium complex efficiency due to the presence of a relevant steric hindrance. Despite that, due to the nature of the interaction between VC2 and ULK1, and the nature of its ligands, the study gives an insight that some modifications on VC2 structure might improve its efficiency as an MRI probe.
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The future GCC-connected environmental risk factors expedited the progression of nCDs. Indeed, the emergence of AFs is becoming a global food security concern. AFs are lethal carcinogenic mycotoxins, causing damage to the liver, kidney, and gastrointestinal organs. Long-term exposure to AFs leads to liver cancer. Almost a variety of food commodities, crops, spices, herbaceous materials, nuts, and processed foods can be contaminated with AFs. In this regard, the primary sections of this review aim to cover influencing factors in the occurrence of AFs, the role of AFs in progression of nCDs, links between GCC/nCDs and exposure to AFs, frequency of AFs-based academic investigations, and world distribution of AFs. Next, the current trends in the application of PPs to alleviate AFs toxicity are discussed. Nearly, more than 20,000 published records indexed in scientific databases have been screened to find recent trends on AFs and application of PPs in AFs therapy. Accordingly, shifts in world climate, improper infrastructures for production/storage of food commodities, inconsistency of global polices on AFs permissible concentration in food/feed, and lack of the public awareness are accounting for a considerable proportion of AFs damages. AFs exhibited their toxic effects by triggering the progression of inflammation and oxidative/nitrosative stress, in turn, leading to the onset of nCDs. PPs could decrease AFs-associated oxidative stress, genotoxic, mutagenic, and carcinogenic effects by improving cellular antioxidant balance, regulation of signaling pathways, alleviating inflammatory responses, and modification of gene expression profile in a dose/time-reliant fashion. The administration of PPs alone displayed lower biological properties compared to co-treatment of these metabolites with AFs. This issue might highlight the therapeutic application of PPs than their preventative content. Flavonoids such as quercetin and oxidized tea phenolics, curcumin and resveratrol were the most studied anti-AFs PPs. Our literature review clearly disclosed that considering PPs in antioxidant therapies to alleviate complications of AFs requires improvement in their bioavailability, pharmacokinetics, tissue clearance, and off-target mode of action. Due to the emergencies in the elimination of AFs in food/feedstuffs, further large-scale clinical assessment of PPs to decrease the consequences of AFs is highly required.
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Today, Alzheimer's disease (AD) is one of the most important neurodegenerative disorders that affected millions of people worldwide. Hundreds of academic investigations highlighted the potential roles of natural metabolites in the cornerstone of AD prevention. Nevertheless, alkaloids are only metabolites that successfully showed promising clinical therapeutic effects on the prevention of AD. In this regard, other plant metabolites such as flavonoids are also considered as promising substances in the improvement of AD complications. The lack of data on molecular mode of action of flavonoids inside brain tissues, and their potential to transport across the blood-brain barrier, a physical hindrance between bloodstream and brain tissues, limited the large-scale application of these compounds for AD therapy programs. Herein, a coupled docking and quantum study was applied to determine the binding mode of flavonoids and three protein kinases involved in the pathogenesis of AD. The results suggested that all docked metabolites showed considerable binding affinity to interact with target receptors, but some compounds possessed higher binding energy values. Because docking simulation cannot entirely reveal the potential roles of ligand substructures in the interaction with target residues, quantum chemical analyses (QCAs) were performed to cover this drawback. Accordingly, QCAs determined that distribution of molecular orbitals have a pivotal function in the determination of the type of reaction between ligands and receptors; therefore, using such quantum chemical descriptors may correct the results of virtual docking outcomes to highlight promising backbones for further developments.Communicated by Ramaswamy H. Sarma.
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Enfermedad de Alzheimer , Flavonoides , Enfermedad de Alzheimer/tratamiento farmacológico , Flavonoides/farmacología , Humanos , Ligandos , Simulación del Acoplamiento Molecular , Simulación de Dinámica MolecularRESUMEN
Naturally occurring anti-diabetic compound curcumin can prevent diabetes complications due to antioxidant and anti-inflammatory properties as well as the attenuation of postprandial hyperglycemia. In this line, we have synthesized thirteen curcumin based derivatives (L1-L13) by multi-component reaction, characterized by IR, 1HNMR, 13C NMR, MS, elemental analysis and evaluated for possible antioxidant properties and α-glucosidase (α-Glu) and α-amylase (α-Amy) inhibitory potential. The curcumin-based pyrano[2,3-d]pyrimidine derivatives could inhibit α-Glu and α-Amy enzyme activity which showed desirable antioxidant activity. Furthermore, among the series, L5, L12, L9, L10, L8 and L11 were identified as more potent inhibitors of α-Glu enzyme than curcumin and the compounds of L12, L4, L9, L5, L10, L8, L13, and L11 were the stronger inhibitors of the α-Amy enzyme in vitro. Besides, among them, L12 had the lowest IC50 for the inhibition of both enzymes. Since strong inhibitors for pancreatic α-Amy result in the progression of severe gastrointestinal side effects, the inhibitors that show the lower α-Amy/α-Glu inhibitory ratio have attracted much attention in medicinal chemistry. Besides, considering antioxidant characteristics of synthesized compounds, the L7 derivative with the highest antioxidant activity and the lowest "α-Amy/α-Glu inhibitory" ratio could be an appropriate candidate for further study through the rational drug design to the exploration of a new class of powerful anti-diabetic drugs.
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Antioxidantes/síntesis química , Antioxidantes/farmacología , Curcumina/química , Diabetes Mellitus/tratamiento farmacológico , Glicósido Hidrolasas/antagonistas & inhibidores , Hipoglucemiantes/farmacología , Animales , Diseño de Fármacos , Hipoglucemiantes/síntesis química , Hipoglucemiantes/química , Intestinos/enzimología , Modelos Moleculares , Simulación del Acoplamiento Molecular , Estructura Molecular , Páncreas/enzimología , Unión Proteica , Conformación Proteica , Ratas , Relación Estructura-Actividad , alfa-Amilasas/genética , alfa-Amilasas/metabolismo , alfa-Glucosidasas/genética , alfa-Glucosidasas/metabolismoRESUMEN
BACKGROUND: Curcumin, as the substantial constituent of the turmeric plant (Curcuma longa), plays a significant role in the prevention of various diseases, including diabetes. It possesses ideal structure features as an enzyme inhibitor, including a flexible backbone, hydrophobic nature, and several available hydrogen bond (H-bond) donors and acceptors. OBJECTIVE: The present study aimed at synthesizing several novel curcumin derivatives and further evaluation of these compounds for possible antioxidant and anti-diabetic properties along with inhibitory effect against two carbohydrate-hydrolyzing enzymes, α-amylase and α-glucosidase, as these enzymes are therapeutic targets for attenuation of postprandial hyperglycemia. METHODS: Therefore, curcumin-based pyrido[2,3-d]pyrimidine derivatives were synthesized and identified using an instrumental technique like NMR spectroscopy and then screened for antioxidant and enzyme inhibitory potential. Total antioxidant activity, reducing power assay and 1,1-diphenyl-2- picrylhydrazyl (DPPHâ¢) radical scavenging activity were done to appraise the antioxidant potential of these compounds in vitro. RESULTS: Compounds L6-L9 showed higher antioxidant activity while L4, L9, L12 and especially L8 exhibited the best selectivity index (lowest α-amylase/α-glucosidase inhibition ratio). CONCLUSION: These antioxidant inhibitors may be potential anti-diabetic drugs, not only to reduce glycemic index but also to limit the activity of the major reactive oxygen species (ROS) producing pathways.
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Curcumina/síntesis química , Curcumina/farmacología , Glicósido Hidrolasas/antagonistas & inhibidores , Antioxidantes/síntesis química , Antioxidantes/química , Antioxidantes/farmacología , Técnicas de Química Sintética , Curcumina/química , Inhibidores de Glicósido Hidrolasas/síntesis química , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/farmacología , Hipoglucemiantes/síntesis química , Hipoglucemiantes/química , Hipoglucemiantes/farmacologíaRESUMEN
Diabetes mellitus (DM) is a chronic metabolic disease which causes millions of death all over the world each year, and its incidence is on increase. The most prevalent form, type 2 DM, is characterized by insulin resistance and ß-cell dysfunction, whereas type 1 DM is due to insulin deficiency as a result of ß-cell destruction. Various classes of synthetic drugs have been developed to regulate glucose homeostasis and combat the development of late-diabetic complications. However, several of these chemical agents are either sub-optimal in their effect and/or may have side effects. Biologically, alkaloids unveiled a wide range of therapeutic effects including anti-diabetic properties. The chemical backbones of these compounds have the potential to interact with a wide range of proteins involved in glucose homeostasis, and thus they have received increasing attention as reliable candidates for drug development. This review sets out to investigate the anti-diabetic potential of plant alkaloids (PAs), and therefore, scientific databases were comprehensively screened to highlight the biological activity of 78 PAs with a considerable anti-diabetic profile. There are not enough clinical data available for these phytochemicals to follow their fingerprint in human, but current studies generally recommending PAs as potent α-glucosidase inhibitors. Except for some classes of monoterpene alkaloids, other compounds showed similar features as well as the presently available anti-diabetic drugs such as amino sugars and other relevant drugs. Moreover, the evidence suggests that PAs have the potential to be used as alternative additives for the treatment of DM, however, further in vitro and in vivo studies are needed to validate these findings.
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Alcaloides/uso terapéutico , Diabetes Mellitus/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Animales , Humanos , Fitoquímicos/uso terapéutico , FitoterapiaRESUMEN
In this study, biodiesel was produced from goat fat in the presence of magnesium oxide (MgO) nano-catalyst using transesterification process. The characteristics of the catalyst were studied using field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM), Brunauer-Emmett-Teller (BET), energy dispersive X-ray/mapping (EDX/Map), Fourier-transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), and dynamic light scattering (DLS). The result showed that the specific surface area and the average pore diameter of the nanocatalyst were 40.44 m2/g and 36.7 nm, respectively, which showed that the catalyst is mesoporous. According to the results of the DLS analysis, the average particle size of the catalyst was determined to be 5.5 nm. Also, the maximum biodiesel yield of 93.12% was obtained at temperature of 70 °C, methanol/oil molar ratio of 12:1, the catalyst content of 1 wt.%, and reaction time of 3 h. In addition, biodiesel was mixed with diesel at different ratios (B25, B50, B75, and B100) to improve fuel properties of the produced biodiesel. The results indicated that the mixtures of B75 and B100 had better density, viscosity, and flash point in comparison to the other mixtures and their properties were within the range of international standards.
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From that time AgNPs become one of the most accessible and important antibacterial agents in our world, thousands of papers published regarding investigating all aspects of these materials. When the time elapsed and novel methods contrived to follow the fingerprint of AgNPs in the in vivo models, some critical concerns and arguments also appeared between researchers about the safety of these compounds for living cells and vital organs. The paper by Dehvari and Ghahaghaei published in Volume 108 International Journal of Biological Macromolecules, pages 1128-1139 (Dehvari and Ghahghaei, 2018) suffered some errors from safety concerns to obscurities in the results essentially needing the amendment to enhance its quality. Though the author(s) idea is commended enough, nevertheless, I could not find a profound trace with their results, and my concerns are discussed in detail as the following lines.
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Antibacterianos/química , Nanopartículas del Metal/química , Plata/química , Animales , HumanosRESUMEN
Reducing the adverse effects of chemotherapy on normal cells such as endothelial cells is a determinant factor of treatment success especially in pregnant women. In this regard, modulatory effect of L-arginine on various cancers is still a controversial topic in cancer therapy. So, this study aimed to compare the effect of L-arginine treatment alone and in combination with 5-fluorouracil (5-FU) on the survival and angiogenesis of primary human umbilical vein endothelial cells (HUVECs) and the breast cancer cell line of MDA-MB-468. Combinations of L-arginine and 5-FU increased cell survival in HUVECs but induced cell death in MDA-MB-468â¯cells. Nitric oxide assay showed an increase of this molecule in both cell lines. Assessments of metabolic changes as well as molecular docking indicated a decrease in glycolytic activity of cancer cells but not normal cells. Angiogenesis induction in HUVECs was confirmed through VEGF and MMP-2,9 up-regulated gene expressions. However, a down-regulation of the above-mentioned genes expression was observed in MDA-MB-468. Furthermore, an in vivo increased angiogenesis and decreased embryo toxicity was observed in combination treatment. Altogether, these findings clearly suggest that L-arginine inhibits cell death induced by 5-FU in HUVECs through attenuating the adverse effects of 5-FU, while it does not do so in breast cancer cells.
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Antineoplásicos/farmacología , Arginina/farmacología , Neoplasias de la Mama/metabolismo , Fluorouracilo/farmacología , Antineoplásicos/efectos adversos , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Arginina/química , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/fisiopatología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Femenino , Fluorouracilo/efectos adversos , Glucólisis/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/citología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Simulación del Acoplamiento Molecular , Óxido Nítrico/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
The original version of this article was published without article note. The article note is given below.
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"Let food be thy medicine and thy medicine be thy food" was expressed by Hippocrates and the health benefits of medicinal plants and natural products have been considered by humans since historic times. The current study aims to investigate the anti-cancer activity of 2-Methylpyridine-1-ium-1-sulfonate (MPS) isolated from bulbs of Allium hirtifolium. The MPS compound (in a dose-dependent manner) induced arrest the AGS cells in G1 and G2/M phases, and Caco-2 cells in G1 and S phases. These findings were associated with the down-regulation of cyclin D1, CDK4, and up-regulation of p21, p27 and p53. According to the morphological observations and DNA fragmentation assay, the MPS compound induced apoptosis in both cell lines, and also cause a significant increase in the expression of Bax/Bcl-2. In this context, our molecular docking results unveiled that the MPS compound has considerable affinity to interact with the minor groove of ctDNA and also with cell cycle kinases. To approve and find the accurate MPS mode of action against cancer cell lines (especially in gastrointestinal cancer) further studies is highly recommended.
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Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Piridinas/farmacología , Compuestos de Piridinio/farmacología , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Allium/química , Antineoplásicos Fitogénicos/química , Células CACO-2 , Caspasa 3/metabolismo , Dominio Catalítico , Línea Celular Tumoral , Quinasa 2 Dependiente de la Ciclina/química , Quinasa 2 Dependiente de la Ciclina/metabolismo , Quinasa 6 Dependiente de la Ciclina/química , Quinasa 6 Dependiente de la Ciclina/metabolismo , Fragmentación del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Espectroscopía de Resonancia Magnética , Simulación del Acoplamiento Molecular , Piridinas/química , Compuestos de Piridinio/químicaRESUMEN
Introduction: Date palm pollen (DPP) is the male reproductive soft powder from date flowers widely used as the valuable dietary supplement to fortify the size of testis and ovarian to increase the power of sex. This part of date palm significantly exhibited anti-diabetic, anti-inflammation and protective effects against male and female infertility. Though the anticancer activity of date fruits was previously reported, the DPP anti-angiogenic effects were not reported, and as the first study, its inhibitory effects were examined in the current study. Methods: The DPP soft powder was collected to prepare its hydro-alcoholic extract to examine its anti-angiogenic activity in an in vitro model. At different concentrations, the cytotoxicity of the prepared extract was examined on human umbilical vein endothelial cells (HUVECs) using lactate dehydrogenase method. Cell proliferation was determined using the MTT assay and cytodex-3D model in collagen gel was used to assay its possible anti-angiogenic activity. The expression of VEGF, MMP-2 and MMP-9 genes was measured using real-time polymerase chain reaction (PCR). Finally, molecular docking simulation was used to highlight the possible role of DPP polyphenols to interact with the associated receptors. Results: The prepared hydro-alcoholic extract exhibited significant anti-angiogenic activity in a dose-dependent manner and decreased the endothelial cell proliferation. The calculated IC50 value for the examined extract in angiogenesis model was 260 µg·mL, respectively. Also, the expression of VEGF, MMP-2 and MMP-9 genes were significantly decreased. Docking simulation results unveiled that the isolated DPP polyphenols have the affinity to interact with ctDNA, VEGF and its receptors. Conclusion: The DPP is the new source of non-toxic anti-cancer agents to use as a dietary supplement in the pre-treatment of cancer.
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The aims of the current study were to evaluate the antibacterial effects of cellulose nanofiber (CNF), chitosan nanofiber (ChNF), CNF/ChNF combination and chitosan alone (Ch) against the isolated bacterial contaminations from the surface of Iranian banknotes using biochemical, disc diffusion and molecular analyses. The results unveiled that the CNF did not show the significant antibacterial effect against isolated bacterial strains, whereas the combination of CNF/ChNF (at concentration 100⯵g/disc 1:1) exhibited the synergistic effects against Stenotrophomonas maltophilia. Also, ChNF (100⯵g/disc) and Ch (100 and 200⯵g/disc) displayed dose-dependent antibacterial effects against the sensitive bacteria including Bacillus subtilis, Bacillus pumilus, Micrococcus sp. Kosakonia cowanii, Brevibacterium frigoritolerans, Escherichia coli standard ATCC 25922, Staphylococcus aureus standard ATCC 25923. On the other hand, chitosan displayed the highest inhibitory effects against Gram-positive bacteria. Our results showed that the coating of banknotes with these compounds is a novel strategy to reduce the bacterial contaminations and increase the durability (or quality) of banknotes, without being toxic to the surrounding environment.
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Antibacterianos , Bacterias/crecimiento & desarrollo , Celulosa , Quitosano , Nanofibras/química , Antibacterianos/química , Antibacterianos/farmacología , Celulosa/química , Celulosa/farmacología , Quitosano/química , Quitosano/farmacología , IránRESUMEN
A new compound named 7-hydroxy-4-methyl-2-oxo-2H-chromene-8-carbaldehyde oxime (7-Oxime) was synthesized and characterized by FT-IR, FT-Raman, 1H NMR and 13C NMR techniques. The conformer possibilities were studied to find the most stable conformer and its molecular geometry. Then, the dimer form of the most stable monomer was built and optimized. Density functional theory (DFT) B3LYP method with 6-311++G(d,p) basis set was applied to analyze the molecular electrostatic potential (MEP), HOMO and LUMO orbitals, the vibrational wavenumbers, the infrared intensities, the Raman scattering activities and several thermodynamic properties (at different temperatures). The stability of the molecule derived from hyperconjugative interactions and charge delocalization has been analyzed by using natural bond orbital (NBO) analysis. In order to find the possible inhibitory activity of 7-Oxime, an accurate molecular blind docking simulation was performed. The results indicated that the mentioned compound has a good binding affinity to interact with the active sites of human α-glucosidase and α-amylase. For the first time, our computational finding suggests that this compound has a potential to be used as a supplementary agent in the pre-management of diabetes mellitus.
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Hipoglucemiantes/química , Oximas/química , Inhibidores de Glicósido Hidrolasas/síntesis química , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/metabolismo , Humanos , Hipoglucemiantes/síntesis química , Hipoglucemiantes/farmacología , Simulación del Acoplamiento Molecular , Oximas/síntesis química , Oximas/farmacología , Transducción de Señal , Análisis Espectral , Vibración , alfa-Amilasas/antagonistas & inhibidores , alfa-Amilasas/metabolismo , alfa-Glucosidasas/metabolismoRESUMEN
Epidermal growth factor receptors (EGFRs) and their cytoplasmic tyrosine kinases play significant roles in cell proliferation and signaling. All the members of the EGFR/ErbB family are primary goals for cancer therapy, particularly for tumors of breast, cervix, ovaries, kidney, esophagus, prostate and non-small-cell lung carcinoma and head and neck tumors. However, the therapeutic ability of accessible anti-ErbB agents is limited. Therefore, recognizing EGF analogues or small organic molecules with high affinity for the extracellular domain of the EGFR is a critical target on cancer research. An effective EGF analogue should have a comparable binding affinity for EGFR in order to create an effective ligand competitive inhibition against circulating wild EGF while fails to transduce appropriate downstream signaling into the cancer cell. In our earlier study we have developed a mutant form of human EGF (mEGF, lacking the four critical amino acid residues; Gln43, Tyr44, Arg45 and Asp46 at the C-terminal of the protein) and its binding properties and mitogenic activity were assessed. The mEGF showed high affinity for EGFR binding domains but caused poor EGFR dimerization and phosphorylation and especially, mEGF induced EGFR internalization. However, underlying mechanism of action of EGF analogues is still unclear and thus considered to be worthwhile for further study. With regard to different effects of the EGF analogue on EGFR activating process, computational analysis of wild EGF/EGFR and mEGF/EGFR complexes (along with EGFt/EGFR complex) were done. Results of the protein dissection identified several interactions within "ligand/EGFR" that are common among EGF and EGFt/mEGF. These results disclose that while several interactions are conserved within EGF/EGFR interfaces, EGF/EGFR interactions on site III interface controls the affinity, EGFR dimerization and subsequent downstream signaling through a heterogeneous set of non-covalent interactions. These findings not only represent the EGFR dynamics complexity but also smooth the path for structure-based design of therapeutics targeting C-terminal region of EGF (and the related domain within the receptor) or EGFR-based imaging probes.
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Factor de Crecimiento Epidérmico/química , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/química , Receptores ErbB/metabolismo , Simulación de Dinámica Molecular , Multimerización de Proteína , Secuencia de Aminoácidos , Sitios de Unión , Disulfuros/química , Humanos , Enlace de Hidrógeno , Células MCF-7 , Unión Proteica , Estructura Cuaternaria de Proteína , Transporte de ProteínasRESUMEN
Natural products have well been recognized as sources of drugs in cancer treatment. Some medicinal plants contain the constituents with potent anti-angiogenic and anti-cancer effects, which have offered great hopes of being used as drugs for treating various cancers. The present study aims at identifying the anti-angiogenic effects of 2-Methylpyridine-1-ium-1-sulfonate (MPS) isolated from the ethyl acetate extract (EA) of Persian shallot (Allium hirtifolium). In a concentration-dependent manner, the MPS was able to inhibit endothelial cell migration and angiogenesis in both in vivo and in vitro assays, and also significantly suppressed proliferation of MCF-7 and MDA-MB-231 human breast cancer cell lines. Additionally, treatment with MPS showed a significant reduction in the vascular endothelial growth factor (VEGF) secretion level and production/activity of matrix metalloproteinases (MMP-2 and MMP-9) in the studied cells. The flow cytometry analysis indicated that MPS suppressed growth of MCF-7 and MDA-MB-231 cells at G0/G1 and S phases, respectively. Our results indicated that the induction of cell cycle arrest was correlated with the obvious changes in expression of p21, p27 and p53. According to the DNA fragmentation assay, MPS caused apoptosis in both cell lines, which confirms the results obtained with the growth assay. Moreover, the compound-mediated apoptosis accompanied with the increase in the Bax/Bcl-2 ratio and caspase-3 and -9 activities. Molecular docking results indicated that the MPS compound can surprisingly bind to VEGF and VEGF receptors and interacts with their critical amino acids. Finally, compounds with anticancer inhibitory activity (e.g. MPS) are abundant in nature and can be obtained from several sources. So, our data can be clinically developed for treating angiogenesis and cancer significantly.
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Allium/química , Inhibidores de la Angiogénesis/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Picolinas/farmacología , Neoplasias de la Mama/metabolismo , Caspasa 3/metabolismo , Línea Celular Tumoral , Femenino , Células Endoteliales de la Vena Umbilical Humana , Humanos , Células MCF-7 , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Simulación del Acoplamiento Molecular , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Recently, due to their biological properties, polyphenol-rich functional foods have been proposed to be unique supplementary and nutraceutical treatments for diabetes mellitus. Inhibition of α-amylase and α-glucosidase enzymes using natural products (especially polyphenols) is a novel oral policy to regulate carbohydrate metabolism and hyperglycemia. The present study aims to evaluate the α-amylase and α-glucosidase inhibitory activity of 26 polyphenols using molecular docking and virtual screening studies. The results speculate that among selected compounds caffeic acid, curcumin, cyanidin, daidzein, epicatechin, eridyctiol, ferulic acid, hesperetin, narenginin, pinoresinol, quercetin, resveratrol and syringic acid can significantly inhibit the α-glucosidase enzyme. In addition, catechin, hesperetin, kaempferol, silibinin and pelargonidin are potent α-amylase inhibitors. Therefore the primary structure of polyphenols can change the inhibitory effect versus the α-amylase and α-glucosidase enzymes. Finally, we speculate that consumption of polyphenol-rich functional foods (by considering the best dose of each compound and assessing their possible side effects) in diabetic patients may be useful for regulating carbohydrate metabolism and related disorders. The findings of the current study may also shed light on a way of generating a new class of amylase/glucosidase inhibitors that will discriminately inhibit the on-target enzymes with negligible undesired off-target side effects.
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Diabetes Mellitus Tipo 2/enzimología , Inhibidores Enzimáticos/química , Hipoglucemiantes/farmacología , Obesidad/enzimología , Fenoles/química , Extractos Vegetales/química , Plantas/química , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Evaluación Preclínica de Medicamentos , Inhibidores de Glicósido Hidrolasas/química , Humanos , Hipoglucemiantes/química , Simulación del Acoplamiento Molecular , Obesidad/tratamiento farmacológico , alfa-Amilasas/química , alfa-Glucosidasas/químicaRESUMEN
Melons have a good source of protease inhibitors. Its fruit and seeds have been used as a traditional medicine. However, its effects on angiogenesis and mechanism of its action remain elusive. Herein trypsin inhibitor from aqueous extract of C. melo seeds (TICMS) was purified. Its effects on different steps of angiogenesis were evaluated. Also, we examined its effects on migration and angiogenesis of endothelial cells. Three dimensional model of TICMS protein was accurately built in which TICMS docked to αVß3 integrin and VEGFR1. Electrophoresis analysis of the purified protein revealed a single band with a molecular mass of about 3kDa. Treatment with TICMS at six doses resulted in a significant decrease of endothelial cell proliferation with an IC50 value of about 20µg/ml. Tubulogenesis assay revealed that a dose dependent anti-angiogenic activity of TICMS (5-40µg/ml). Also, TICMS had inhibitory effects on VEGF, MMP-2 and MMP-9 secretion. Our docking result speculated that TICMS could bind to the cleft between the αVß3 integrin and it able to decrease the activity of this receptor. The TICMS was also able to interact with VEGFR1 receptor, but with low probability. Based on our study, TICMS could be used as a specific angiogenesis inhibitor.