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1.
Front Mol Biosci ; 11: 1414119, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39290991

RESUMEN

Introduction: During the last decade, there has been a significant rise in the use of therapeutic antibodies or passive immunotherapy for treating various conditions like inflammation and cancer. However, these proteins face challenges reaching the brain and often require specialized delivery methods such as single-domain antibodies (sdAbs). Traditional antibodies struggle to efficiently cross the blood-brain barrier (BBB), hindering their effectiveness. Receptor-mediated transcytosis (RMT) offers a promising pathway for transporting large molecules essential for brain function and treatment across the BBB. Methods: SdAbs and peptide ligands with an affinity for RMT receptors are commonly employed to enhance the transport of biotherapeutics compounds across the BBB. This research used a sdAbs phage-displayed library from 13 camelus dromedarius samples to identify sdABs that specifically bind to and are internalized by human BBB endothelial cells (ECs) through in vivo panning. Results and discussion: One sdAb, defined as FB24, was isolated, sequenced, translated into an open reading frame (ORF), and subjected to three-dimensional (3D) modeling. Molecular docking and molecular dynamics simulations were carried out by the HADDOCK web server and GROMACS, respectively, to evaluate the interaction between FB24 and EC receptors in silico. The docking results revealed that FB24 exhibited binding activity against potential EC receptors with -1.7 to -2.7 ranged z score and maintained a stable structure. The docked complex of FB24-RAGE (receptor for advanced glycation end products, also known as advanced glycation end product receptor [AGER]) showed 18 hydrogen bonds and 213 non-bonded contacts. It was chosen for further analysis by molecular dynamics simulations by GROMACS. This complex showed a stable condition, and its root mean square deviation (RMSD) was 0.218 nm. The results suggest that FB24 could serve as a suitable carrier vector for transporting therapeutic and diagnostic agents across the BBB to the brain through a non-invasive route.

2.
Phys Chem Chem Phys ; 25(35): 23937-23953, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37642543

RESUMEN

Due to the increasing demand for electrochemical energy storage, rechargeable lithium-ion batteries (LIBs) are gaining more and more attention. However, much research still needs to be conducted to enhance their cycling and storage capacity. Recently, computational studies have provided valuable information for LIB development, which is very difficult and expensive to obtain experimentally. In this study, molecular dynamics (MD) simulation and first-principles calculations are performed to investigate the potential of a Cu-BHT MOF and phosphorene as the cathode and anode, respectively. An external electrical field is applied to simulate the charging process and study lithium-ion behavior during migration from the cathode to the anode in an electrolyte. Time and space-dependent variables such as energy, radial distribution function, mean square displacement (MSD), density, and so on have been used to evaluate the studied system. The MSD calculations showed that there are two different regimes in the MSD curves of Li-ions; diffusion and cage. In the designed LIB, the cathode has a better performance in the presence of a high electric field, whereas under an external electric field of 1.5 V Å-1, more lithium ions move from the cathode to the anode. By using first-principles calculations the lithium insertion in phosphorene and Cu-BHT is studied in various configurations and concentrations. The obtained results indicated that the adsorption energy of lithium on the cathode in the most stable configuration is -3.21 eV which is enough to prevent the clustering effect. Furthermore, the interaction of Li with phosphorene is strong enough and forms a stable complex. It is found that by insertion of Li into the anode the band gap is decreased which indicates the possibility of fast charging of LIBs. Investigation of different concentrations of ions reveals that the Li-Li repulsive interactions lead to a decrease in the adsorption energy of Li with the anode and cathode. The results of this study provide an in-depth insight into LIBs.

3.
ACS Appl Bio Mater ; 6(7): 2826-2836, 2023 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-37327458

RESUMEN

Prodrug and drug delivery systems are two effective strategies for improving the selectivity of chemotherapeutics. Herein, via molecular dynamics (MD) simulation and free energy calculation, the effectiveness of the graphene oxide (GO) decorated with the pH-sensitive prodrug (PD) molecules in cancer therapy is investigated. PEI-CA-DOX (prodrug) was loaded onto the GO surface, in which the hydrogen bonding and pi-pi stacking interactions play the main role in the stability of the GO-PD complex. Due to the strong interaction of GO and PD (about -800 kJ/mol), the GO-PD complex remains stable during the membrane penetration process. The obtained results confirm that GO is a suitable surface for hosting the prodrug and passing it through the membrane. Furthermore, the investigation of the release process shows that the PD can be released under acidic conditions. This phenomenon is due to the reduction of the contribution of electrostatic energy in the GO and PD interaction and the entry of water into the drug delivery system. Moreover, it is found that an external electrical field does not have much effect on drug release. Our results provide a deep understanding of the prodrug delivery systems, which helps the combination of nanocarriers and modified chemotherapy drugs in the future.


Asunto(s)
Neoplasias , Profármacos , Humanos , Profármacos/uso terapéutico , Doxorrubicina/uso terapéutico , Neoplasias/tratamiento farmacológico , Concentración de Iones de Hidrógeno
4.
Sci Rep ; 13(1): 2501, 2023 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-36781871

RESUMEN

Although nature is a rich source of potential drugs and drug leads, the widespread application of natural products (NPs) is limited due to their poor absorption when administered orally. A strategy of using phytosome has emerged as a promising technique to increase the bioavailability of NPs. Here, a comprehensive computational investigation is performed to explore the nature of interactions in the formation of phytosomes between phosphatidylcholine (PC) and a series of polyphenols (PP), including epigallocatechin-3-gallate (Eg), luteolin (Lu), quercetin (Qu), and resveratrol (Re). Our quantum mechanical calculation revealed that the intermolecular hydrogen bonds (HBs) of phosphate and glycerol parts of PC with the polyphenol compounds are the main driving force in the formation of phytosomes. The strongest HB (with energy HB = - 108.718 kJ/mol) is formed between the Eg molecule and PC. This hydrogen bond results from the flexible structure of the drug which along with several van der Waals (vdW) interactions, makes Eg-PC the most stable complex (adsorption energy = - 164.93 kJ/mol). Energy decomposition analysis confirms that the electrostatic interactions (hydrogen bond and dipole-diploe interactions) have a major contribution to the stabilization of the studied complexes. The obtained results from the molecular dynamics simulation revealed that the formation of phytosomes varies depending on the type of polyphenol. It is found that the intermolecular hydrogen bonds between PP and PC are a key factor in the behavior of the PP-PC complex in the self-aggregation of phytosome. In Eg-PC, Lu-PC, and Qu-PC systems, the formation of strong hydrogen bonds (HBCP < 0 and ∇2ρBCP > 0) between PP and PC protects the PP-PC complexes from degradation. The steered molecular dynamics simulation results have a good agreement with experimental data and confirm that the phytosome platform facilitates the penetration of PP compounds into the membrane cells.


Asunto(s)
Productos Biológicos , Polifenoles , Fosfolípidos , Fitosomas , Lecitinas
5.
Comput Biol Med ; 146: 105566, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35598351

RESUMEN

Although vaccines have been significantly successful against coronavirus, due to the high rate of the Omicron variant spread many researchers are trying to find efficient drugs against COVID-19. Herein, we conducted a computational study to investigate the binding mechanism of four potential inhibitors (including disulfide derivatives isolated from Ferula foetida) to SARS-CoV-2 main protease. Our findings revealed that the disulfides mainly interacted with HIS41, MET49, CYS145, HIS64, MET165, and GLN189 residues of SARS-CoV-2 main protease. The binding free energy decomposition results also showed that the van der Waals (vdW) energy plays the main role in the interaction of HIS41, MET49, CYS145, HIS64, MET165, and GLN189 residues with the inhibitors. Furthermore, it is found that the Z-isomer derivatives have a stronger interaction with SARS-CoV-2, and the strongest interaction belongs to the (Z)-1-(1-(methylthio)propyl)-2-(prop-1-enyl)disulfane (ΔG = -18.672 kcal/mol). The quantum mechanical calculations demonstrated that the second-order perturbation stabilization energy and the electron density values for MET49-ligand interactions are higher than the other residue-ligand complexes. This finding confirms the stronger interaction of this residue with the ligands.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Ferula , Disulfuros , Ferula/química , Ferula/metabolismo , Ligandos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Inhibidores de Proteasas/química , SARS-CoV-2
6.
Comput Biol Med ; 143: 105336, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35219189

RESUMEN

Polyhistidine is among the cell-penetrating peptides that in an acidic environment can facilitate membrane transition. Keeping in mind that the pH of the tumor intercellular medium is ∼5.5, in this paper, we examined the functionalization of a convenient drug delivery vehicle with cell-penetrating poly(l-histidine) to provide a smart drug delivery system. Classical molecular dynamics and metadynamics simulations are used to investigate the interactions between doxorubicin, carbon nanotube, poly(l-histidine), and the cell membrane. Metadynamics simulation revealed that not only the global minimum of FES reduced in an acidic environment but also the difference between the free energy of Doxorubicin as being adsorbed on poly(l-histidine) compared to when being freely dissolved in the aqueous medium show a dramatic reduction. MD simulations showed that functionalization of carbon nanotube with poly(l-histidine) groups has no detriment effect in the adsorption of Doxorubicin. The L-J interaction between Doxorubicin and carrier at the equilibrium states reached around -600 kJ/mol, both for the pristine and functionalized carbon nanotube. The coulombic interactions for both complexes were negligible in the neutral environment. At the acidic environment, the L-J interactions retained the same values as the neutral, while the coulombic interactions showed positive values, which suggested its participation in the detachments. At the vicinity of the membrane, the complexes retain their integrity both in neutral and acidic environments. In the present work, we performed metadynamics simulation to investigate the effects of poly(l-histidine) on the adsorption capacity of the carbon nanotubes, and explore the adsorption/desorption processed of Doxorubicin on pristine and poly(l-histidine)-grafted carbon nanotube. The resulted complexes were then subjected to interact with the POPC membrane model in both acidic and neutral environments via molecular dynamic simulations. The results provided here will hopefully help in a better understanding of future drug delivery systems and be helpful in designing more efficient and smart drug delivery systems.

7.
Chemosphere ; 281: 130970, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34289624

RESUMEN

A novel strategy was described to fabricate hematite-MOF materials with morphologies (core-shell) and (composite) as an efficient peroxymonosulfate (PMS) activator for degrading ciprofloxacin (CIP) antibiotics. First, α-Fe2O3 nanoparticles (NPs) with a size distribution range of 80 nm were prepared by surfactant-assisted reflux method. Then, cobalt-based metal-organic framework (ZIF-67) was grown onto the α-Fe2O3 NPs with ultrasonic and solvothermal method, which can control the nanostructures morphology. The physicochemical properties of these nanostructures were probed by ATR-IR, WA-XRD, FESEM, VSM, TEM, and EDS spectroscopy. The results showed that all the added CIP (20 ppm) antibiotics were completely degraded in 30 min in the α-Fe2O3/ZIF-67 (0.10 g/L) and PMS (0.20 g/L) system with rate constant of 0.130 min-1. To validate the merits of the α-Fe2O3/ZIF-67, α-Fe2O3@ZIF-67 core-shell nanostructures were also applied under similar conditions. The findings demonstrated that Co/Fe species within α-Fe2O3/ZIF-67 composite catalyzed PMS synergistically to the formation of the OH and SO4- and 1O2 for CIP degradation. Furthermore, α-Fe2O3/ZIF-67 showed good recyclability enabling facile separation of the catalyst from reaction mixtures using an external magnet. The current protocol can be a useful criterion in designing various Magnetic-MOF composites with controlled morphologies for environmental remediation.


Asunto(s)
Ciprofloxacina , Nanocompuestos , Catálisis , Compuestos Férricos
8.
J Biomed Mater Res A ; 109(10): 1912-1921, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33797184

RESUMEN

The development of drug delivery systems (DDSs) has raised hopes for targeted cancer therapy. Smart polymers can be conjugated with several nanoparticles and increase their efficiency in biomedical applications. In this work, the classical molecular dynamics and well-tempered metadynamics simulations are performed to study the behavior of black phosphorus (BPH) nanosheet functionalized with polyethylenimine (PEI) in adsorption, diffusion, and release of doxorubicin (DOX) anticancer drug. Adsorption of the drug on PEI-BPH surface is mainly due to the formation of strong pi-pi interaction between the drug and BPH. The drug-binding to the nanosheet is enhanced by the intermolecular hydrogen bond that formed between DOX and PEI. The energy values for the interaction of DOX with BPH and PEI are calculated to be about - 180 and - 50 kJ/mol, respectively. The obtained results indicated that the adsorption of the drug molecules on the nanosheet destroyed the hydration layer around the BPH-PEI surface. The free energy calculation for DDS shows a global minimum in which the distances of DOX from BPH surface and PEI are about 1.0 and 0.5 nm, respectively. Furthermore, the diffusion of DDS into the membrane has a macropinocytosis pathway that is in line with experimental observations. Moreover, it is found that, unlike the isolated DOX, the drug in complex with BPH-PEI can be easily penetrated membrane cells. The study of the pH-responsive release of the drug shows the high solubility of the polymer in the water environment plays the main role in swelling of DDS and the release of the DOX molecules.


Asunto(s)
Doxorrubicina/uso terapéutico , Sistemas de Liberación de Medicamentos , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Fósforo/química , Polímeros/química , Difusión , Doxorrubicina/química , Doxorrubicina/farmacología , Liberación de Fármacos , Humanos , Simulación de Dinámica Molecular , Neoplasias/patología , Electricidad Estática , Propiedades de Superficie , Termodinámica
9.
RSC Adv ; 11(31): 18809-18817, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-35478640

RESUMEN

Polymeric nanoparticles have emerged as efficient carriers for anticancer drug delivery because they can improve the solubility of hydrophobic drugs and also can increase the bio-distribution of drugs throughout the bloodstream. In this work, a computational study is performed on a set of new pH-sensitive polymer-drug compounds based on an intelligent polymer called poly(ß-malic acid) (PMLA). The molecular dynamics (MD) simulation is used to explore the adsorption and dynamic properties of PMLA-doxorubicin (PMLA-DOX) interaction with the graphene oxide (GOX) surface in acidic and neutral environments. The PMLA is bonded to DOX through an amide bond (PMLA-ami-DOX) and a hydrazone bond (PMLA-hz-DOX) and their adsorption behavior is compared with free DOX. Our results confirm that the polymer-drug prodrug shows unique properties. Analysis of the adsorption behavior reveals that this process is spontaneous and the most stable complex with a binding energy of -1210.262 kJ mol-1 is the GOX/PMLA-hz-DOX complex at normal pH. On the other hand, this system has a great sensitivity to pH so that in an acidic environment, its interaction with GOX became weaker while such behavior is not observed for the PMLA-ami-DOX complex. The results obtained from this study provide accurate information about the interaction of the polymer-drug compounds and nanocarriers at the atomic level, which can be useful in the design of smart drug delivery systems.

10.
J Biomol Struct Dyn ; 39(15): 5613-5618, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-32673145

RESUMEN

Dual delivery of Doxorubicin (DOX) and Paclitaxel (PTX) anticancer drug molecules with boron nitride (BN) and phosphorene (PH) nanosheets are investigated using molecular dynamics (MD) simulation. Several quantities are employed to examine the adsorption mechanism of DOX and PTX on the carriers. The obtained results indicate that the drug molecules spontaneously move toward the carriers and form stable complexes. In the interaction of the drugs and BN, the contribution of van der Walls (vdW) is higher than electrostatic energy which can be related to the formation of strong π-π interactions between the drugs and the carrier. Moreover, in the same manner, in the adsorption of drugs on the PH surface, the role of vdW interaction is more than electrostatic energy. Moreover, the oxidative properties of BN and PH nanosheets are examined. The obtained results indicated that the diffusion coefficient values of PTX and DOX molecules in the presence of hydroxyl groups are increased, which can attribute to the blocking effect of functional groups.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Antineoplásicos , Paclitaxel , Compuestos de Boro , Doxorrubicina , Portadores de Fármacos , Sistemas de Liberación de Medicamentos
11.
J Biomol Struct Dyn ; 39(11): 3892-3899, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32448080

RESUMEN

The adsorption behavior of Anastrozole (ANA) and Melphalan (MEL) anticancer drugs on the surface of silicene nanosheet (SNS) and functionalized SNS with folic acid (FA-SNS) is investigated and compared using the density functional theory (DFT) and molecular dynamics (MD) simulation. The DFT calculation is performed at the M06-2X/6-31G** level to characterize the optimized geometry properties of the designed complexes. The calculated adsorption energies are in the range from -65.59 to -144.23 kJ/mol, indicating the drug absorption on the surface of SNS and FA-SNS is exergonic. The π-π interaction between the drugs and SNS surface is the main driving force in the formation of drug-carriers complexes. The quantum theory of atoms in molecule (QTAIM) results reveal that the interaction of SNS and FA-SNS with both drugs has a non-covalent nature. The natural bond orbital (NBO) analysis shows that the charge is transferred from the drug molecules to carrier in all of the investigated complexes. Furthermore, MD simulations reveal that the contribution of van der Waals energy in drug-carrier interactions is more than electrostatic energy. Also, the obtained results demonstrate that the movement of drug molecules toward the carriers is spontaneous. Our study provides insights into the drug delivery capability of SNS and FA-SNS for the delivery of two drugs (ANA and MEL).Communicated by Ramaswamy H. Sarma.


Asunto(s)
Antineoplásicos , Simulación de Dinámica Molecular , Teoría Funcional de la Densidad , Portadores de Fármacos , Ácido Fólico
12.
Amino Acids ; 52(10): 1465-1478, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33098474

RESUMEN

Graphene-amino acid interaction is gaining significance mainly based on its possible biomedicine applications. The density functional theory (DFT) calculation and molecular dynamics simulation (MD) are applied to obtain a comprehensive understanding of the adsorption mechanism of three kinds of amino acids, namely, alanine (Ala), glycine (Gly), and valine (Val) over the surface of graphene and functionalized graphene nanosheets. In this study, several analyses such as solvation energy, adsorption energy, intermolecular distances, and charge properties are used to explore the adsorption behavior of amino acid on the nanosheets. The calculated adsorption energies show that the interaction of amino acids with functionalized graphene is greater than the pristine graphene. Regarding DFT computations, the adsorption of Val on the graphene about - 10 kJ/mol is stronger than Gly and Ala. Meanwhile, it is found that the geometrical parameters and electronic properties of graphene change drastically upon functionalization, and the formation of hydrogen bonds between -COOH functional group and amino acids enhances the adsorption energy about 12-30%. To obtain a deeper comprehension of the interaction nature, the atoms in molecules (AIM) and the natural bond orbital (NBO) studies have been performed. Furthermore, the MD simulations are employed to assess the dynamic properties of our designed systems. The results from the present study demonstrate that the movement of the amino acids into the carriers is spontaneous and forms stable complexes.


Asunto(s)
Aminoácidos/química , Grafito/química , Nanoestructuras/química , Adsorción , Teoría Funcional de la Densidad , Enlace de Hidrógeno , Simulación de Dinámica Molecular , Termodinámica
13.
J Mol Graph Model ; 98: 107613, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32320908

RESUMEN

The stability of Gemcitabine (Gem) anticancer drug on the hexagonal boron nitride (h-BN) and functionalized h-BN with polyethylene glycol (PEG-h-BN) as drug delivery carriers (DDSs) is investigated. The density functional theory (DFT) calculations, molecular dynamics (MD) simulation and Metadynamics simulations are used to study the nature of h-BN-Gem interactions as well as the role of PEG group to increase the efficiency of the DDS. The results of DFT calculations reveal that the drug physisorbed on the h-BN surface through the formation of π-π stacking with an adsorption energy range -15.08 kJ/mol to -90.74 kJ/mol. Moreover, the obtained results show that the grafting the PEG group to h-BN cause to π-π stacking is reinforced by the formation of strong HBs and leads to increase adsorption energy about 20%. There is a good agreement between DFT calculation and MD simulation results. Also, The MD simulations demonstrate in adsorption of the drug on the carriers, the contribution of van der Waals energy is more than the electrostatic energy. The well-tempered metadynamics simulations are performed to find the free energy surface (FES) of the studied systems. The FES for the Gem/h-BN and Gem/PEG-h-BN interfaces show the global minimum at around 3.0-6.0 Å and 1.2 Å, respectively. The orientational analysis proves that the global minimum can be related to the formation of π-π stacking and HB interaction.


Asunto(s)
Portadores de Fármacos , Polímeros , Adsorción , Compuestos de Boro , Desoxicitidina/análogos & derivados , Polietilenglicoles , Gemcitabina
14.
J Biomol Struct Dyn ; 38(9): 2737-2745, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31311443

RESUMEN

The surface modification ability is one of the remarkable characters of graphene (G) nanosheet. Based on this strategy, G surface is modified with folic acid (FA) to improve the targeting delivery of chemotherapy agents. The dual delivery strategy for the transport of doxorubicin (DOX) and camptothecin (CPT) by using G and folic acid functionalized G nanocarriers is examined. The density functional theory (DFT) and molecular dynamics (MD) simulation are employed to gain a deep insight into the nature of the drug and the carrier interactions. The obtained results indicate that the drug molecules spontaneously move toward the carriers and form stable complexes. In the graphene-based systems, the drug molecules form strong π-π interactions with the carrier surface. It is found that the FA functionalization of G (FA-G) not only improves targeting effect but also reinforces drug-carrier interaction. Furthermore, the MD and DFT results show that interaction of DOX molecules with G and FA-G is stronger than CPT. We believe that the results obtained from this study can be helpful to improve the drug effectiveness in cancer treatment.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Grafito , Camptotecina , Teoría Funcional de la Densidad , Doxorrubicina , Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Ácido Fólico , Simulación de Dinámica Molecular
15.
J Biomol Struct Dyn ; 38(5): 1322-1334, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31002028

RESUMEN

The present study focuses on the prediction and investigation of binding properties of penicillamine with pure (5,5) single-walled carbon nanotube (SWCNT) and functionalized SWCNT (f-SWCNT) through the B3LYP and M06-2X functionals using the 6-31G** basis set. The electronic and structural properties, adsorption energy and frontier molecular orbitals of various configurations are examined. Our theoretical results indicated that the interaction of the nanotubes with penicillamine molecule is weak so that the drug adsorption process is typically physisorption. Also, results of theoretical calculations show that the adsorption of the drug molecule on f-SWCNT is stronger with shorter intermolecular distances in comparison to pure SWCNT. The natural bond orbital (NBO) analysis of studied systems demonstrates that the charge is transferred from penicillamine molecule to the nanotubes. Furthermore, molecular dynamics (MD) simulation is employed to evaluate the dynamic and diffusion behavior of drug molecule on SWCNT and f-SWCNT. Energy results show that drug molecule spontaneously moves toward the carriers, and the van der Waals energy contributions in drug adsorption are more than electrostatic interaction. The obtained results from MD simulation confirm that the functionalization of SWCNT leads to increase in the solubility of the carrier in aqueous solution.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Antineoplásicos , Nanotubos de Carbono , Adsorción , Teoría Funcional de la Densidad , Simulación de Dinámica Molecular , Penicilamina
16.
RSC Adv ; 10(72): 44533-44544, 2020 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-35517168

RESUMEN

Due to the extreme pore volume and valuable surface area, zeolitic imidazole frameworks (ZIFs) are promising vehicles that enhance the delivery of therapeutic agents to tissues. Furthermore, these nanoporous materials have high stability in the pH and temperature of the surrounding healthy cells (37 °C and pH = 7) and an exotic potential to deform in carcinogenic environment (T > 37 °C and pH ∼ 5.5), which make them perfect smart drug delivery vehicle candidates. In this work, a series of molecular dynamics (MD) and metadynamics simulations have been performed to gain molecular insight into the mechanisms involved in the process of co-loading of doxorubicin (DOX) and EpiGalloCatechin-3 Gallate (EGCG) on ZIF-8, which form a smart drug delivery system (SDDS). The obtained results revealed that DOX was adsorbed on the carrier mostly through electrostatic interactions (E coul = ∼-1200 kJ mol-1, E tot = -1700 kJ mol-1), and EGCG was stacked on ZIF-8 mainly via van der Waals interactions (E L-J = ∼-600 kJ mol-1, E tot = ∼-1200 kJ mol-1). It is worth mentioning that the drug-drug L-J interactions (E L-J = ∼500 kJ mol-1) were also important in the co-loading process. The insertion of DOX and EGCG as additive agents to the initial ZIF-8/EGCG and ZIF-8/DOX systems led to the enhancement of the drug-carrier pair interactions to about ∼-2300 kJ mol-1 and ∼-2000 kJ mol-1, respectively. This finding implied that the drug-drug interactions had a complementary role in the development of SDDS via ZIF-8. From the metadynamics simulation, it was found that the geometry of the drugs is a determining factor in an efficient co-loading SDDS.

17.
RSC Adv ; 10(52): 31106-31114, 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-35520638

RESUMEN

The objective of this study is to develop a controlled and water-soluble delivery system for doxorubicin (DOX) based on the coating of graphene (G) with a smart polymer. A combination of polyethyleneimine (PEI) and G-DOX is investigated by performing density functional theory (DFT) calculations and molecular dynamics (MD) simulations. Several parameters have been employed to evaluate the effect of PEI on the adsorption and release mechanisms of DOX. The obtained results indicated that the binding energy of the drug molecule on G in the presence of PEI is enhanced by about 20% under neutral conditions, whereas the drug absorption becomes weaker in an acidic environment so that DOX could be separated from the carrier surface using near-infrared radiation (NIR). Based on the atom in molecule (AIM) theory, two hydrogen bonds with strengths of about -12.59 and -39.99 kJ mol-1 have been established. Furthermore, evaluating the dynamic behavior of the designed systems in water solution shows that the polymer in physiological pH rapidly adsorbed on the drug-carrier complex. However, at acidic pH, it is quickly desorbed from the carrier surface and the G-DOX complex can be exposed to cancer cells. The obtained results of the present research may be used in future experimental work to design smart DDSs.

18.
Saudi J Biol Sci ; 26(3): 473-480, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30899161

RESUMEN

The aim of this study was to determine the correlation between PM2.5 and NO2 pollutants and oxidative stress marker (8-isoprostane) and lung function tests (FVC and FEV1) in healthy children who were living and studying in three different areas of Ahvaz city including A1: Naderi site with high traffic, A2: Alavi Alley site with average traffic, and A3: Ein 2 site with low traffic (a rural area on the suburb of Ahvaz). 30 students in the 12-13 year-old range were selected from each studied zone (1, 2 and 3 sites) during three months of year. Of each student, one sample was taken every two weeks to measure 8-isoprostane of exhaled breath condensate (EBC). Air pollution data were collected from three air quality monitoring stations. Also, the relationship between air pollution and 8-isoprostane as well as lung function tests were determined using generalized estimating equations (GEE). The mean concentration of PM2.5 and NO2 in A1, A2 and A3 areas were 116, 92 and 45 (µg/m3) also 77, 53 and 14 (ppb) respectively. Among all studied students, there was a significant correlation between the increase of mean concentration of PM2.5 and NO2 in 1-4 before sampling day, increased 8-isoprostane concentration and decreased FEV1, while there was no significant correlation between them and decreased FVC. In A1 site, an increase in IQR (13 µg/m3) PM2.5 and IQR (6.5 ppb) NO2 on 1-4 days before sampling was associated with 0.38 unit (95% CI: 0.11, 0.65) and 1.1 unit (95% CI: 0.85, 1.35) increase in 8-isoprostane concentration, also decreased 121 ml and 190 ml FEV1, respectively. Results showed that the short-term exposure to traffic-related air pollution can decrease the values of lung function indices and increase the oxidative stress. It may adversely affect children's lungs.

19.
J Mol Model ; 23(8): 222, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28702805

RESUMEN

Carbon nanotubes (CNTs) are widely used in drug delivery systems (DDSs) due to their unique chemical and physical properties. Investigation of interactions between biomolecules and CNTs is an interesting and important subject in biological applications. In this study, we used molecular dynamics (MD) simulation to investigate the adsorption mechanism of the anticancer drug paclitaxel (PTX) on pristine and functionalized CNTs (f-CNT) in aqueous solutions. Our theoretical results show that PTX can be adsorbed on sidewalls of CNT in different methods. In the case of f-CNTs, PTX can be adsorbed on the functional groups due to the existence of polar interactions. These interactions in the CNT functionalized with polyethylene glycol (PEG), are more than the other investigated systems. Furthermore, it was found that the solubility of CNTs in aqueous solution is increased by functionalization. This is related to the intermolecular hydrogen bonds between functional groups and solvent molecules. The PEG group has the greatest effect on the solubility of the CNT in aqueous solution due to more polar interactions.


Asunto(s)
Sistemas de Liberación de Medicamentos , Simulación de Dinámica Molecular , Nanotubos de Carbono/química , Paclitaxel/administración & dosificación , Adsorción , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Paclitaxel/química , Paclitaxel/uso terapéutico , Resultado del Tratamiento
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