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1.
Int J Biol Macromol ; 265(Pt 1): 130641, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38460623

RESUMEN

Due to its involvement in skin maintenance and repair, topical administration of recombinant human growth hormone (rhGH) is an interesting strategy for therapeutic purposes. We have formulated and characterized a topical rhGH-loaded liposomal formulation (rhGH-Lip) and evaluated its safety, biological activity, and preventive role against UVB-induced skin damage. The rhGH-Lip had an average size and zeta potential of 63 nm and -33 mV, respectively, with 70 % encapsulation efficiency. The formulation was stable at 4 °C for at least one year. The SDS-PAGE and circular dichroism results showed no structural alterations in rhGH upon encapsulation. In vitro, studies in HaCaT, HFFF-2, and Ba/F3-rhGHR cell lines confirmed the safety and biological activity of rhGH-Lip. Franz diffusion cell study showed increased rhGH skin permeation compared to free rhGH. Animal studies in nude mice showed that liposomal rhGH prevented UVB-induced epidermal hyperplasia, angiogenesis, wrinkle formation, and collagen loss, as well as improving skin moisture. The results of this study show that rhGH-Lip is a stable, safe, and effective skin delivery system and has potential as an anti-wrinkle formulation for topical application. This study also provides a new method for the topical delivery of proteins and merits further investigation.


Asunto(s)
Hormona de Crecimiento Humana , Ratones , Animales , Humanos , Hormona de Crecimiento Humana/farmacología , Hormona de Crecimiento Humana/metabolismo , Ratones Desnudos , Piel/metabolismo , Liposomas/metabolismo , Absorción Cutánea
2.
J Biomol Struct Dyn ; : 1-21, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38345131

RESUMEN

The main purpose of this research was to evaluate the role of α-lactalbumin (α-LA), ß-lactoglobulin (ß-LG), and ß-Caseins (ß-CN) in the binding interaction between Nano Resveratrol (Nano Res), as binary and ternary systems. This investigation was fulfilled through the application of multi-spectroscopic, transmission electron microscopy (TEM), field emission scanning electron microscope (FE-SEM), conductometry, isothermal titration calorimetry (ITC), and molecular dynamics (MD) simulation techniques. Fluorescence spectroscopy observations illustrated the effectiveness of Nano Res throughout the quenching of α-LA, (α-LA-ß-LG), and (α-LA-ß-CN) complexes, confirming the occurrence of interaction through the combination of static and dynamic mechanisms. An enhancement in the temperature of all three complexes caused a decrease in their Ksv and Kb values, which indicates the static and dynamic behavior of their interactions. The obtained thermodynamic parameters proved the dominance of electrostatic interaction as the binding force of both binary and ternary systems. The observed properties of Tyr or Trp residues in proteins through the data of synchronous spectroscopy at Δλ = 15 and 60 nm, respectively, demonstrated the closer positioning of (α-LA-ß-CN) complex to the proximity of Trp residues when compared to the two other cases. According to the resonance light scattering (RLS) measurements, the detection of a much greater RLS intensity in (α-LA-ß-CN) Nano Res complex suggested the production of a larger complex. Furthermore, the conductometry outcomes displayed an increase in molar conductivity and therefore approved the occurrence of interaction between Nano Res and proteins in both binary and ternary systems. The spherical shape of Nano Res was confirmed through the results of FE-SEM and TEM analyses. The conformational changes of proteins throughout the binding of Nano Res was evaluated by circular dichroism (CD) technique, while molecular docking and MD simulations affirmed the binding of Nano Res to α-LA, (α-LA-ß-LG), and (α-LA-ß-CN) complexes as binary and ternary systems. These In Silico study data confirm the results of in vitro assessments. The occurrence of changes in the secondary structure of ß-galactosidase was implied through the increased enzyme catalytic activity induced by the interaction of different lactose concentrations.Communicated by Ramaswamy H. Sarma.

3.
Luminescence ; 39(1): e4634, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38286605

RESUMEN

In this study, cellulose nanocrystals (CNCs) were synthesized from celery stalks to be used as the platform for quercetin delivery. Additionally, CNCs and CNCs-quercetin were characterized using the results of scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and zeta potential, while their interactions with human holo-transferrin (HTF) were also investigated. We examined their interaction under physiological conditions through the exertion of fluorescence, resonance light scattering, synchronized fluorescence spectroscopy, circular dichroism, three-dimensional fluorescence spectroscopy, and fluorescence resonance energy transfer techniques. The data from SEM and TEM exhibited the spherical shape of CNCs and CNCs-quercetin and also, a decrease was detected in the size of quercetin-loaded CNCs from 676 to 473 nm that indicated the intensified water solubility of quercetin. The success of cellulose acid hydrolysis was confirmed based on the XRD results. Apparently, the crystalline index of CNCs-quercetin was reduced by the interaction of CNCs with quercetin, which also resulted in the appearance of functional groups, as shown by FTIR. The interaction of CNCs-quercetin with HTF was also demonstrated by the induced quenching in the intensity of HTF fluorescence emission and Stern-Volmer data represent the occurrence of static quenching. Overall, the effectiveness of CNCs as quercetin vehicles suggests its potential suitability for dietary supplements and pharmaceutical products.


Asunto(s)
Apium , Nanopartículas , Humanos , Celulosa/química , Quercetina , Transferrina/química , Adsorción , Nanopartículas/química , Digestión
4.
DNA Cell Biol ; 43(1): 26-38, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38079271

RESUMEN

In this study, we determined the interaction of piperine and calf thymus DNA (ct DNA) in Tris-HCl buffer solution at pH = 6.8 and also evaluated the binding mechanism through the data of multi-spectroscopic techniques along with thermal melting and viscosity measurements. The outcomes of fluorescence quenching confirmed the occurrence of interactions between piperine and ctDNA and pointed out the role of piperine as the quencher. In addition, the KSV values were measured at three different temperatures of 298, 303, and 308 K to be 4.5 × 107 M-1, 5.65 × 107 M-1, and 9.36 × 107 M-1, respectively, which suggested the dominance of dynamic mechanism as the fluorescence quenching of piperine-ctDNA. The thermodynamic parameters revealed the predominance of hydrophobic forces in the interaction of ctDNA with piperine. According to the resonance light scattering data, the formation of a complex between piperine and ctDNA led to the creation of a larger particle. Ethidium bromide (EB) and acridine orange (AO) displacement studies, along with the ionic effects of NaCl and KI assessments, confirmed the interaction of piperine-ctDNA through a groove binding mode. The melting temperature assay of ctDNA upon the addition of piperine concentration indicated the probable groove binding of piperine to ctDNA, which was affirmed by relative viscosity measurement as well. The lack of detecting any alterations in the circular dichroism (CD) spectrum of CD investigation verified as a characteristic sign of groove binding mechanism and also confirmed all the experimental results with regard to the binding of piperine-ctDNA complex. Next to observing a concentration and time-dependent cytotoxicity in MDA-MB-231 cells, the impact of piperine on increasing lipid peroxidation and decreasing the activity of superoxide dismutase was also noticed. Apparently, piperine is capable of inducing caspase-3 activity as well.


Asunto(s)
Alcaloides , Benzodioxoles , Neoplasias de la Mama , Piperidinas , Alcamidas Poliinsaturadas , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Fluorescencia , ADN/metabolismo , Termodinámica , Línea Celular , Caspasas , Espectrometría de Fluorescencia , Simulación del Acoplamiento Molecular
5.
Cell Biochem Biophys ; 82(1): 175-191, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37978103

RESUMEN

Riboflavin (RF) is a vitamin that only exists in plants and microorganisms and must be procured externally by humans. On the other hand, there are two major allergic factors in cow's milk, including ß-lactoglobulin (ßLG) and ß-casein (ßCN), while their allergic properties can be eliminated by binding to micronutrients. In this regard, we examined the binding process of RF to ßLG and ßCN in the binary and ternary systems by different spectroscopies such as zeta potential, electric conductivity, and molecular modeling. According to the result of the fluorescence spectrum regarding the interaction of RF with ßLG and ßCN in binary and ternary systems, an increase in RF concentration declined the fluorescence intensity of three systems and also caused the quenching of proteins. Static quenching plays a pivotal role in the formation of stable interactions. The obtained thermodynamic parameters by Van't Hoff equation ascertained the predominance of hydrogen bonds and van der Waals interaction in all the systems. Considering how the negative value of ΔH0 resulted in the negative value of ΔG0, the systems were assumed to be enthalpy driven. The outcomes of circular dichroism (CD) disclosed that the attachment of RF to the targets of systems increased their a-helix content, which particularly included the binding of RF to ßLG that led to the conversion of ß-sheet to α-helix content. As indicated by the results of zeta potential, the low concentration of RF contained the dominance of hydrophobic forces in the interactions, whereas the enlargement of this concentration prevailed electrostatic forces. Moreover, conductometry measurements showed an extension in the rate of ionizable groups due to the addition of RF to the systems, which may increase the probability of an interaction between RF, ßCN, and ßLG in binary and ternary systems. In consistency with the outcomes of molecular dynamics simulation, the data of molecular docking approved the capability of RF in forming strong and stable interactions with ßCN and ßLG.


Asunto(s)
Caseínas , Lactoglobulinas , Humanos , Caseínas/metabolismo , Simulación del Acoplamiento Molecular , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Dicroismo Circular , Termodinámica , Simulación de Dinámica Molecular , Riboflavina/metabolismo , Unión Proteica , Sitios de Unión , Espectrometría de Fluorescencia
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 309: 123815, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38154302

RESUMEN

In this work, the interaction of human serum albumin (HSA) and human holo-transferrin (HTF) with the prepared Nano-Kaempferol (Nano-KMP) through oil-in-water procedure was investigated in the form of binary and ternary systems by the utilization of different spectroscopy techniques along with molecular simulation and cancer cell experiments. According to fluorescence spectroscopy outcomes, Nano-KMP is capable of quenching both proteins as binary systems by a static mechanism, while in the form of (HSA-HTF) Nano-KMP as the ternary system, an unlinear Stern-Volmer plot was elucidated with the occurrence of both dynamic and static fluorescence quenching mechanisms in the binding interaction. In addition, the two acquired Ksv values in the ternary system signified the existence of two sets of binding sites with two different interaction behaviors. The binding constant values of HSA-Nano KMP, HTF-Nano-KMP, and (HSA-HTF) Nano-KMP complexes formation were (2.54 ± 0.03) × 104, (2.15 ± 0.02) × 104 and (1.43 ± 0.04) × 104M-1at the first set of binding sites and (4.68 ± 0.05) × 104 M-1 at the second set of binding sites, respectively. The data of thermodynamic parameters confirmed the major roles of hydrogen binding and van der Waals forces in the formation of HSA-Nano KMP and HTF-Nano KMP complexes. The thermodynamic parameter values of (HSA-HTF) Nano KMP revealed the dominance of hydrogen binding and van der Waals forces in the first set of binding sites and hydrophobic forces for the second set of binding sites. Resonance light scattering (RLS) analysis displayed the existence of a different interaction behavior for HSA-HTF complex in the presence of Nano-KMP as the ternary system. Moreover, circular dichroism (CD) technique affirmed the conformational changes of the secondary structure of proteins as binary and ternary systems. Molecular docking and molecular dynamics simulations (for 100 ns) were performed to investigate the mechanism of KMP binding to HSA, HTF, and HSA-HTF. Next to observing a concentration and time-dependent cytotoxicity, the down regulation of PI3K/AkT/mTOR pathway resulted in cell cycle arrest in SW480 cells.


Asunto(s)
Fosfatidilinositol 3-Quinasas , Albúmina Sérica Humana , Humanos , Simulación del Acoplamiento Molecular , Unión Proteica , Fosfatidilinositol 3-Quinasas/metabolismo , Espectrometría de Fluorescencia , Sitios de Unión , Dicroismo Circular , Albúmina Sérica Humana/química , Termodinámica , Transferrina/química , Hidrógeno , Agua/metabolismo
7.
J Biomol Struct Dyn ; : 1-18, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37403294

RESUMEN

The aim of this study was to investigate the behavior interaction of α-Casein-B12 and ß-Casein-B12 complexes as binary systems through the methods of multiple spectroscopic, zeta potential, calorimetric, and molecular dynamics (MD) simulation. Fluorescence spectroscopy denoted the role ofB12as a quencher in both cases of α-Casein and ß-Casein fluorescence intensities, which also verifies the existence of interactions. The quenching constants of α-Casein-B12 and ß-Casein-B12 complexes at 298 K in the first set of binding sites were 2.89 × 104 and 4.41 × 104 M-1, while the constants of second set of binding sites were 8.56 × 104 and 1.58 × 105 M-1, respectively. The data of synchronized fluorescence spectroscopy at Δλ = 60 nm were indicative of the closer location of ß-Casein-B12 complex to the Tyr residues. Additionally, the binding distance between B12 and the Trp residues of α-Casein and ß-Casein were obtained in accordance to the Förster's theory of nonradioactive energy transfer to be 1.95 nm and 1.85 nm, respectively. Relatively, the RLS results demonstrated the production of larger particles in both systems, while the outcomes of zeta potential confirmed the formation of α-Casein-B12 and ß-Casein-B12 complexes and approved the existence of electrostatic interactions. We also evaluated the thermodynamic parameters by considering the fluorescence data at three varying temperatures. According to the nonlinear Stern-Volmer plots of α-Casein and ß-Casein in the presence of B12 in binary systems, the two sets of binding sites indicated the detection of two types of interaction behaviors. Time-resolved fluorescence results revealed that the fluorescence quenching of complexes are static mechanism. Furthermore, the outcomes of circular dichroism (CD) represented the occurrence of conformational changes in α-Casein and ß-Casein upon their binding to B12 as the binary system. The experimental results that were obtained throughout the binding of α-Casein-B12 and ß-Casein-B12 complexes were confirmed by molecular modeling.Communicated by Ramaswamy H. Sarma.

8.
Iran J Basic Med Sci ; 26(6): 635-644, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37275756

RESUMEN

Objectives: Today, the non-covalent PEGylation methods of protein pharmaceuticals attract more attention and possess several advantages over the covalent approach. In the present study, Amino Acid-mPEGs (aa-mPEGs) were synthesized, and the human Growth Hormone (hGH) stability profile was assessed in their presence and absence. Materials and Methods: aa-mPEGs were synthesized with different amino acids (Trp, Glu, Arg, Cys, and Leu) and molecular weights of polymers (2 and 5 KDa). The aa-mPEGs were analyzed with different methods. The physical and structural stabilities of hGH were analyzed by SEC and CD spectroscopy methods. Physical stability was assayed at different temperatures within certain intervals. Molecular dynamics (MD) simulation was used to realize the possible mode of interaction between protein and aa-mPEGs. The cell-based method was used to evaluate the cytotoxicity. Results: HNMR and FTIR spectroscopy indicated that aa-mPEGs were successfully synthesized. hGH as a control group is known to be stable at 4 °C; a pronounced change in monomer degradation is observed when stored at 25 °C and 37 °C. hGH:Glu-mPEG 2 kDa with a molar ratio of 1:1 to the protein solution can significantly increase the physical stability. The CD spectroscopy method showed that the secondary structure of the protein was preserved during storage. aa-mPEGs did not show any cytotoxicity activities. The results of MD simulations were in line with experimental results. Conclusion: This paper showed that aa-mPEGs are potent excipients in decreasing the aggregation of hGH. Glu-mPEG exhibited the best-stabilizing properties in a harsh environment among other aa-mPEGs.

9.
J Biomol Struct Dyn ; : 1-15, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37340682

RESUMEN

A significant contributing factor in the development of breast cancer is the estrogens. The synthesis of estrogens is primarily facilitated by aromatase (CYP19), a cytochrome P450 enzyme. Notably, aromatase is expressed at a higher level in human breast cancer tissue compared with the normal breast tissue. Therefore, inhibiting aromatase activity is a potential strategy in hormone receptor-positive breast cancer treatment. In this study, Cellulose Nanocrystals (CNCs) were obtained from Chicory plant waste through a sulfuric acid hydrolysis method with the objective of investigating that whether the obtained CNCs could act as an inhibitor of aromatase enzyme, and prevent the conversion of androgens to estrogens. Structural analysis of CNCs was carried out using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD), while morphological results were obtained using AFM, TEM, and FE-SEM. Furthermore, the nano-particles were found to be spherical in shape with a diameter range of 35-37 nm and displayed a reasonable negative surface charge. Stable transfection of MCF-7 cells with CYP19 has demonstrated the ability of CNCs to inhibit aromatase activities and prevent cell growth by interfering with the enzyme activities. Spectroscopic results revealed the binding constant of CYP19-CNCs and (CYP19-Androstenedione)-CNCs complexes to be 2.07 × 103 L/gr and 2.06 × 104 L/gr, respectively. Conductometry and CD data reported different interaction behaviors among CYP19 and CYP19-Androstenedione complexes at the presence of CNCs in the system. Moreover, the addition of CNCs to the solution in a successive manner resulted in the enhancement of the secondary structure of the CYP19-androstenedione complex. Additionally, CNCs showed a marked reduction in the viability of cancer cells compared to normal cells by enhancing the expression of Bax and p53 at protein and mRNA levels, and by decreasing mRNA levels of PI3K, AKT, and mTOP, as well as protein levels of PI3Kg-P110 and P-mTOP, in MCF-7 cells after incubation with CNCs at IC50 concentration. These findings confirm the decrease in proliferation of breast cancer cells associated with induction of apoptosis through down-regulation of the PI3K/AKT/mTOP signaling pathway. According to the provided data, the obtained CNCs are capable of inhibiting aromatase enzyme activity, which has significant implications for the treatment of cancer.Communicated by Ramaswamy H. Sarma.

10.
Bioimpacts ; 13(1): 5-16, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36817002

RESUMEN

Introduction: Here, the interaction behavior between propyl acridones (PA) and calf thymus DNA (ct-DNA) has been investigated to attain the features of the binding behavior of PA with ct-DNA, which includes specific binding sites, modes, and constants. Furthermore, the effects of PA on the conformation of ct-DNA seem to be quite significant for comprehending the medicine's mechanism of action and pharmacokinetics. Methods: The project was accomplished through means of absorbance studies, fluorescence spectroscopy, circular dichroism, viscosity measurement, thermal melting, and molecular modeling techniques. Results: The intercalation of PA has been suggested by fluorescence quenching and viscosity measurements results while the thermal melting and circular dichroism studies have confirmed the thermal stabilization and conformational changes that seem to be associated with the binding. The binding constants of ct-DNA-PA complex, in the absence and presence of EMF, have been evaluated to be 6.19 × 104 M-1 and 2.95 × 104 M-1 at 298 K, respectively. In the absence of EMF, the ∆H0 and ∆S0 values that occur in the interaction process of PA with ct-DNA have been measured to be -11.81 kJ.mol-1 and 51.01 J.mol-1K-1, while in the presence of EMF they were observed to be -23.34 kJ.mol-1 and 7.49 J.mol-1K-1, respectively. These numbers indicate the involvement of multiple non-covalent interactions in the binding procedure. In a parallel study, DNA-PA interactions have been monitored by molecular dynamics simulations; their results have demonstrated DNA stability with increasing concentrations of PA, as well as calculated bindings of theoretical ΔG0. Conclusion: The complex formation between PA and ct-DNA has been investigated in the presence and absence of EMF through the multi spectroscopic techniques and MD simulation. These findings have been observed to be parallel to the results of KI and NaCl quenching studies, as well as the competitive displacement with EB and AO. According to thermodynamic parameters, electrostatic interactions stand as the main energy that binds PA to ct-DNA. Regarding the cases that involve the Tm of ct-DNA, EMF has proved to increase the stability of binding between PA and ct-DNA.

11.
Iran J Basic Med Sci ; 26(2): 190-199, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36742143

RESUMEN

Objectives: In this work, we propose an efficient preparation process for the synthesis of natural carbon quantum dots (NCQDs) by the usage of orange pericarp as the carbon natural resource, which is performed through hydrothermal treatment and top-down approaches. Materials and Methods: The structural, morphological, average size, and optical properties of synthesized NCQDs were investigated via dynamic light scattering (DLS), transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), atomic force microscopy (AFM), field emission scanning electron microscope (FESEM), energy dispersive x-ray spectroscopy (EDX), ultraviolet-visible spectroscopy (UV-Vis), and fluorescence PL spectra. Results: The shape of obtained NCQDs was observed to be spherical in the results of TEM analysis with an average size of 6-7 nm which confirms NCQDs essence. The signs of a strong peak (absorption) at around 282 nm throughout the UV-vis spectrum have been detected. The provided FTIR spectroscopy confirmed the existence of functional groups above the NCQDs surface. Furthermore, the surface charge of -11 mV through the obtained zeta potential regarding the synthesized NCQDs has been identified. MTT assay on mouse colon carcinoma cells (C26) demonstrated the lack of any signs of toxicity in NCQDs. Conclusion: The obtained NCQDs contain high photo-stability, excellent PL activity, and efficient fluorescent emission based on excitation. The results of kinetic studies revealed the ability of NCQDs to inhibit trypsin activity in a non-competitive model, which qualifies them as potent inhibitors and quenchers of trypsin. It can be suggested that the synthesized NCQDs have the potential of functioning as a sustainable and eco-friendly source for various applications such as sensors for detecting Ca2+ and Zn2+ and trypsin biosensor for determining enzyme activity.

12.
J Fluoresc ; 33(4): 1537-1557, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36787038

RESUMEN

The interaction of Rebeccamycin with calf thymus (ctDNA) in the absence and presence of H1 was investigated by molecular dynamics, multi-spectroscopic, and cellular techniques. According to fluorescence and circular dichroism spectroscopies, Rebeccamycin interacted with ctDNA in the absence of H1 through intercalator or binding modes, while the presence of H1 resulted in revealing theintercalator, as the dominant role, and groove binding modes of ctDNA-Rebeccamycin complex. The binding constants, which were calculated to be 1.22 × 104 M-1 and 7.92 × 105 M-1 in the absence and presence of H1, respectively, denoted the strong binding of Rebeccamycin with ctDNA. The binding constants of Rebeccamycin with ct DNA in the absence and presence of H1 were calculated at 298, 303 and 308 K. Considering the thermodynamic parameters (ΔH0 and ΔS0), both vander waals forces and hydrogen bonds played predominant roles throughout the binding of Rebeccamycin to ctDNA in the absence and presence of H1. The outcomes of circular dichroism suggested the lack of any major conformational changes in ctDNA upon interacting with Rebeccamycin, except some perturbations in native B-DNA at local level. Additionally, the effect of NaCl and KI on ctDNA-Rebeccamycin complex provided further evidence for the reliance of their interaction modes on substituted groups. The observed increase in the relative viscosity of ctDNA caused by the enhancement of Rebeccamycin confirmed their intercalation and groove binding modes in the absence and presence of H1. Moreover, the assessments of molecular docking simulation corroborated these experimental results and also elucidated the effectiveness of Rebeccamycinin inhibiting and proliferating T24 and 5637 cells. Meanwhile, the ability of Rebeccamycin in inhibiting cell proliferation and tumor growth through the induction of apoptosis by down regulating the PI3K/AKT signaling pathway were provided.


Asunto(s)
Simulación de Dinámica Molecular , Neoplasias de la Vejiga Urinaria , Humanos , Simulación del Acoplamiento Molecular , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Regulación hacia Abajo , ADN/química , Dicroismo Circular , Termodinámica , Transducción de Señal , Apoptosis , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
13.
J Biomol Struct Dyn ; 41(20): 10302-10314, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-36510660

RESUMEN

Butyl-paraben (BP) is one of the most widely used preservatives in numerous foodstuffs, skin care products, and a variety of drugs, and trypsin is the main digestive enzyme, the research on the binding between the two is essential for human health. In the present paper, the effect of BP on trypsin has been explored using experimental and computational techniques to evaluate BP toxicity at the protein level. The obtained results from molecular docking and kinetic assay revealed BP was embedded in the hydrophobic cavity-S1 binding pocket of the enzyme to inhibit its activity by a competitive model. Intrinsic fluorescence of trypsin after interaction with BP revealed the static mode of quenching. FRET indicated that the distance of the enzyme to BP is 1.89 nm with high energy efficiency. Thermodynamic results proved that BP spontaneously bound to trypsin in an enthalpy-driven manner, the van der Waals interactions and H-bonds serving as the predominant forces in binding processes. CD spectroscopy and molecular dynamics (MD) simulation revealed that the trypsin structure transformed from the ß-Sheet structure to the unordered Coil structure upon interacting with BP. Resonance light scattering (RLS), synchronous fluorescence, and three-dimensional (3 D) spectroscopies further supported the alteration in the conformation of trypsin. Differential scanning calorimetry (DSC) showed that trypsin was somewhat destabilized in the presence of BP. Accordingly, all of the experimental data were confirmed by MD simulation.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Parabenos , Humanos , Sitios de Unión , Unión Proteica , Tripsina/química , Simulación del Acoplamiento Molecular , Termodinámica , Espectrometría de Fluorescencia , Dicroismo Circular
14.
J Biomol Struct Dyn ; 41(9): 4180-4193, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-35437091

RESUMEN

The interaction between calf thymus DNA (ctDNA) and Malathion in the absence and presence of Histone 1 has been enquired by the means of spectroscopic, viscometry, molecular modeling, and cell viability assay techniques. Malathion is capable of quenching the fluorescence of ct DNA in the absence and presence of H1. The binding constants of Malathion-ctDNA complex in the absence of H1 have been calculated to be 6.62 × 104, 4.31 × 104 and 1.93 × 104 M-1 at 298, 303, and 308 K, respectively that revealed static quenching in complex formation. The observed negative values of enthalpy and entropy changes indicate that the main binding interaction forces were van der Waals force and hydrogen bonding. The binding constant between Malathion and single-stranded ctDNA (ss ctDNA) seemed to be much weaker than that of Malathion and double-stranded ctDNA (ds ctDNA). Furthermore, Malathion can induce detectable alterations in the CD spectrum of ctDNA, along with changes in its viscosity. In the presence of H1, fluorescence quenching of ctDNA-Malathion complex displays dynamic behavior and binding constants were perceived to be 1.66 × 104, 2.93 × 104 and 5.77 × 104 M-1 at 298, 303, and 308 K, respectively. The different of interaction behavior between ctDNA and Malathion in the absence and presence of H1 clearly revealed H1 role in the complex formation and forces change between ctDNA and Malathion. The positive values of enthalpy and entropy changes have suggested that binding process is primarily driven by hydrophobic interactions. The tendency to interact with ss ctDNA, reduced viscosity have designated that the Malathion bound to ctDNA in the presence of H1 is groove binding. The results of molecular docking and molecular dynamics simulation also confirmed potent interactions between Malathion and the macromolecules in the binary and ternary systems.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Malatión , Simulación de Dinámica Molecular , Simulación del Acoplamiento Molecular , Supervivencia Celular , ADN/química , Termodinámica , Espectrometría de Fluorescencia/métodos , Espectrofotometría Ultravioleta , Dicroismo Circular
15.
Iran J Basic Med Sci ; 25(10): 1234-1242, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36311203

RESUMEN

Objectives: Superparamagnetic iron oxide nanoparticles (SPIONs) have been considered promising non-invasive imaging tools in medicine. However, their high surface energy leads to NPs aggregation, while non-targeted SPIONs can cause cytotoxic effects on normal cells. In this work, we evaluated the in vitro potential of polyethyleneimine (PEI)-SPIONs targeted by PNC-27 peptide as a double targeting agent throughout early cancer diagnosis. Materials and Methods: Initially, PEI was conjugated to PNC-27 with HDM-2-binding domain. Then, SPIONs were loaded into PEI-PNC-27 through the ligand exchange method. The physicochemical characteristics of the synthesized NPs were evaluated. The cytotoxicity and targeting efficiency were assayed against HT-29 and CT-26 cell lines along with NIH-3t3 as normal cells by MTT method and Prussian blue staining test, respectively. Results: The mean diameter of synthesized carriers was obtained in the range of 86.6 - 116.1 nm with a positive charge. According to the cytotoxicity results, the binding and uptake abilities of the PNC-27 peptide by cancer cells were significantly higher than that of the NIH-3t3 cells. However, the results were indicative of the more toxic impacts of targeted synthesized NPs against CT-26 cancer cell line when being compared with HT-29 cells, which may be caused by the different cytotoxicity mechanisms of NPs. In addition, the targeted carriers and SPIONs were present inside and around the cells with HDM-2 expression along with only a few non-targeted vectors, while displaying no appearance throughout the normal cell. Conclusion: The results indicated the efficiency of targeted PEI-coated SPIONs for cancer diagnostic applications.

16.
J Mol Model ; 28(9): 283, 2022 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-36044079

RESUMEN

The application of antineoplastic chemotherapeutic agents causes a common side effect known as chemotherapy-induced peripheral neuropathy (CIPN) that leads to reducing the quality of patient's life. This research involves the performance of molecular docking and molecular dynamic (MD) simulation studies to explore the impact of terpenoids of Ginkgo biloba on the targets (CB-1, TLR4, FAAH-1, COX-1, COX-2) that can significantly affect the controlling of CIPN's symptoms. According to the in-vitro and in-vivo investigations, terpenoids, particularly ginkgolides B, A, and bilobalide, can cause significant effects on neuropathic pain. The molecular docking results disclosed the tendency of our ligands to interact with mainly CB1 and FAAH-1, as well as partly with TLR4, throughout their interactions with targets. Terpene trilactone can exhibit a lower rate of binding energy than CB1's inhibitor (7dy), while being precisely located in the CB1's active site and capable of inducing stable interactions by forming hydrogen bonds. The analyses of MD simulation proved that ginkgolide B was a more suitable activator and inhibitor for CB1 and TLR4, respectively, when compared to bilobalide and ginkgolide A. Moreover, bilobalide is capable of inhibiting FAAH-1 more effectively than the two other ligands. According to the analyses of ADME, every three ligands followed the Lipinski's rule of five. Considering these facts, the exertion of three ligands is recommended for their anti-inflammatory, neuroprotective, and anti-nociception influences caused by primarily activating CB1 and inhibiting FAAH-1 and TLR4; in this regard, these compounds can stand as potential candidates for the control and treatment of CIPN's symptoms.


Asunto(s)
Bilobálidos , Enfermedades del Sistema Nervioso Periférico , Ciclopentanos/química , Ciclopentanos/farmacología , Furanos/farmacología , Ginkgo biloba/química , Humanos , Lactonas/química , Simulación del Acoplamiento Molecular , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Enfermedades del Sistema Nervioso Periférico/tratamiento farmacológico , Enfermedades del Sistema Nervioso Periférico/prevención & control , Extractos Vegetales , Terpenos/farmacología , Receptor Toll-Like 4
17.
Luminescence ; 37(11): 1836-1845, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35946171

RESUMEN

As a waste material, the amazing potential of cellulose nanocrystals (CNCs) isolated from Citrus medica L. pericarp in being a natural resource of lingo-cellulosic products has never been investigated before. In the present study, an alkaline pretreatment and a two-step bleaching procedure were applied to conduct the desired acid hydrolysis by the usage of 64% sulfuric acid at 50°C for 105 min. The extracted CNCs were distinguished through the means of transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), atomic force microscopy (AFM), Fourier-transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), zeta potential, and energy-dispersive X-ray spectroscopy (EDX). The elimination of peaks, which were accountable for the inducement of hemicelluloses and lignin, was confirmed by the FTIR results and were also validated by the outcomes of XRD that proved the gentle removal of non-cellulosic components. The morphology and size of CNCs were indicated through the FESEM and TEM results. In addition, the spherical forms of synthesized CNCs were observed with a diameter of 46 nm throughout the FESEM images, while displaying a value of 42.54 nm as well due to TEM micrographs. The obtained zeta potential displayed a reasonable negative surface charge for CNCs. Furthermore, the cytotoxicity assessment of this product on fibroblast cells was performed to study their susceptibility for bio-medical and cosmetic industrial applications, which resulted in the lack of exhibiting any cytotoxic effects. In conformity to the outcomes of TEM and FESEM, the results of AFM revealed a fine dispersion and spherical form of cellulose nanoparticles. The interaction between HMG-CoA reductase and CNC was studied by the usage of multi-spectroscopic methods and enzyme kinetics to explore the binding mechanism of HMG-CoA reductase-CNC system. Reduced catalytic activity of the occurrence of changes in the secondary structure of HMG-CoA reductase was as a result of interacting with CNC causing a reduction in its catalytic activity.


Asunto(s)
Citrus , Nanopartículas , Celulosa/química , Nanopartículas/química , Colesterol , Oxidorreductasas
18.
Mol Cell Probes ; 65: 101847, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35843391

RESUMEN

SARS-COV-2 stands as the source of the most catastrophic pandemic of this century, known as COVID-19. In this regard, we explored the effects of five Pistacia sp. active ingredients on the most crucial targets of SARS-COV-2, including 3CLpro, PLpro, RdRp, helicase, NSP15, and E protein. The results of molecular docking determined 1,2,3,4,6-pentagalloyl glucose (PG) as the most effective compound of Pistacia sp, which also confirmed its excellent binding affinities and stable interactions with helicase (-10.76 kcal/mol), RdRp (-10.19 kcal/mol), E protein (-9.51 kcal/mol), and 3CLpro (-9.47 kcal/mol). Furthermore, MD simulation was conducted to investigate the stability of all complexes throughout a 100 ns. In contrast to PLpro and NSP15, the analyses of Lennard-Jones potential, RMSDas, PCA, and SASA verified the ability of PG in forming stable and adequate interactions with RdRp, helicase, 3CLpro, and E protein due to standing as an effective inhibitor among the six targets, these data proposed the capability of PG, the most important compound of Pistacia sp., in inducing antiviral, anti-inflammatory, and antioxidant impacts on RdRp, helicase, 3CLpro, and E protein. Therefore, the possibility of inhibiting the replication and transcription processes and viral pathogenesis of SARS-COV-2 may be facilitated through the application of PG.


Asunto(s)
COVID-19 , Pistacia , Cisteína Endopeptidasas , Glucosa , Simulación del Acoplamiento Molecular , Pistacia/metabolismo , ARN Polimerasa Dependiente del ARN , SARS-CoV-2
19.
J Biomol Struct Dyn ; 40(21): 11154-11172, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34328379

RESUMEN

In this work, we investigated the simultaneous binding of curcumin (CUR) to human serum albumin (HSA) and human-holo transferrin (HTF) in the roles of binary and ternary systems. The binding affinity and binding site of protein-protein interaction were studied by the methods of multiple spectroscopic and molecular dynamics (MD) simulation. According to the results, the measurements for binding constant of HSA-CUR, HTF-CUR and (HSA-HTF) CUR complexes were observed to be 1.51 × 105, 7.93 × 104 and 1.44 × 105 M-1 respectively. Thermodynamic parameters were considered to be set at three varying temperatures including 298, 303, and 308 K. In conformity to the negative values of ΔH0 and ΔS0 the significant roles of hydrogen binding and van der-Waals forces in the formation of complexes are quiet evident. The binding distance between Trp residues of HSA, HTF and HSA-HTF upon interaction with CUR, were acquired by applying the Förster's theory of non-radioactive energy transfer and reported to be 2.04 nm, 1.78 nm, and 1.86 nm, respectively. In accordance with the conductometry and Resonance light scattering (RLS) results, there were different interaction behaviors among the HSA-HTF complex and CUR in ternary system when being compared to the outcomes of binary system. The secondary structure of all three cases increased as the CUR concentration was intensified, which confirmed the inducement of proteins conformational changes through the application of circular dichroism (CD) technique. The experimental results that were acquired throughout the binding of HSA-CUR, HTF-CUR, and (HSA-HTF) CUR complexes were approved by molecular modeling.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Curcumina , Albúmina Sérica Humana , Humanos , Albúmina Sérica Humana/química , Simulación de Dinámica Molecular , Transferrina/química , Unión Proteica , Dicroismo Circular , Sitios de Unión , Termodinámica , Espectrometría de Fluorescencia/métodos , Simulación del Acoplamiento Molecular
20.
Luminescence ; 37(2): 310-322, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34862709

RESUMEN

With advances in new drug therapies, it is essential to understand the interactions between drugs and target molecules. In this study, we applied multiple spectroscopic techniques including absorbance, fluorescence, circular dichroism spectroscopy, viscosity, thermal melting, calorimetric, and molecular dynamics (MD) simulation to study the interaction between 2-Ethyl-5-(4-methylphenyl) pyramido pyrazole ophthalazine trione (PPF) and calf thymus DNA (ct DNA) in the absence or presence of histone H1. PPF exhibits a high binding affinity towards ct DNA in binary and ternary systems. In addition, the result for the binding constant was observed within the range 104 M-1 achieved through fluorescence quenching data, while the values for enthalpy and entropy changes for ct DNA-PPF and (ct DNA-H1) PPF complexes were measured to be -72.54 kJ.mol-1 , -161.14 J.mol-1  K-1 , -85.34 kJ.mol-1 , and -19.023 J.mol-1  K-1 , respectively. Furthermore, in accordance with circular dichroism spectra, the inducement of ct DNA structural changes was observed during binding of PPF and H1 in binary and ternary system forms. The essential roles of hydrogen bonding and van der Waals forces throughout the interaction were suggested using thermodynamic parameters. According to the obtained data, the interaction mode of ct DNA-PPF and (ct DNA-H1) PPF complexes was intercalation binding. Suggested by the MD simulation study, the ct DNA-H1 complex caused a reduction in the stability of the DNA structure in the presence or absence of ligand, which demonstrated that PPF as an intercalating agent can further distort the structure. The information achieved from this study will be very helpful in understanding the effects of PPF on the conformational state of ct DNA in the absence or presence of the H1 molecule, which seems to be quite significant for clarifying the mechanisms of action and its pharmacokinetics.


Asunto(s)
ADN , Simulación de Dinámica Molecular , Dicroismo Circular , ADN/genética , Simulación del Acoplamiento Molecular , Pirazoles , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Termodinámica
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