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1.
Artigo em Inglês | MEDLINE | ID: mdl-38630254

RESUMO

We aimed to perform a comprehensive study on the development and characterization of silymarin (Syl)-loaded niosomes as potential drug delivery systems. The results demonstrate significant novelty and promising outcomes in terms of morphology, size distribution, encapsulation efficiency, in vitro release behavior, free energy profiles of Syl across the niosome bilayer, hydrogen bonding interactions, antimicrobial properties, cytotoxicity, and in vivo evaluations. The physical appearance, size, and morphology assessment of free niosomes and Syl-loaded niosomes indicated stable and well-formed vesicular structures suitable for drug delivery. Transmission electron microscopy (TEM) analysis revealed spherical shapes with distinct sizes for each formulation, confirming uniform distribution. Dynamic light scattering (DLS) analysis confirmed the size distribution results with higher polydispersity index for Syl-loaded niosomes. The encapsulation efficiency of Syl in the niosomes was remarkable at approximately 91%, ensuring protection and controlled release of the drug. In vitro release studies showed a sustained release profile for Syl-loaded niosomes, enhancing therapeutic efficacy over time. Free energy profiles analysis identified energy barriers hindering Syl permeation through the niosome bilayer, emphasizing challenges in drug delivery system design. Hydrogen bonding interactions between Syl and niosome components contributed to energy barriers, impacting drug permeability. Antimicrobial assessments revealed significant differences in inhibitory effects against S. aureus and E. coli. Cytotoxicity evaluations demonstrated the superior tumor-killing potential of Syl-loaded niosomes compared to free Syl. In vivo studies indicated niosome formulations' safety profiles in terms of liver and kidney parameters compared to bulk Syl, showcasing potential for clinical applications. Overall, this research highlights the promising potential of Syl-loaded niosomes as effective drug delivery systems with enhanced stability, controlled release, and improved therapeutic outcomes.

2.
Med Biol Eng Comput ; 62(2): 423-436, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37889430

RESUMO

Human immunodeficiency virus type 1 (HIV-1) is a major global health problem, with over 38 million people infected worldwide. Current anti-HIV-1 drugs are limited in their ability to prevent the virus from replicating inside host cells, making them less effective as preventive measures. In contrast, viral inhibitors that inactivate the virus before it can bind to a host cell have great potential as drugs. In this study, we aimed to design mutant peptides that could block the interaction between gp120 and the CD4 receptor on host cells, thus preventing HIV-1 infection. We designed a 20-amino-acid peptide that mimicked the amino acids of the CD4 binding site and docked it to gp120. Molecular dynamics simulations were performed to calculate the energy of MMPBSA (Poisson-Boltzmann Surface Area) for each residue of the peptide, and unfavorable energy residues were identified as potential mutation points. Using MAESTRO (Multi AgEnt STability pRedictiOn), we measured ΔΔG (change in the change in Gibbs free energy) for mutations and generated a library of 240 mutated peptides using OSPREY software. The peptides were then screened for allergenicity and binding affinity. Finally, molecular dynamics simulations (via GROMACS 2020.2) and control docking (via HADDOCK 2.4) were used to evaluate the ability of four selected peptides to inhibit HIV-1 infection. Three peptides, P3 (AHRQIRQWFLTRGPNRSLWQ), P4 (VHRQIRQWFLTRGPNRSLWQ), and P9 (AHRQIRQMFLTRGPNRSLWQ), showed practical and potential as HIV inhibitors, based on their binding affinity and ability to inhibit infection. These peptides have the ability to inactivate the virus before it can bind to a host cell, thus representing a promising approach to HIV-1 prevention. Our findings suggest that mutant peptides designed to block the interaction between gp120 and the CD4 receptor have potential as HIV-1 inhibitors. These peptides could be used as preventive measures against HIV-1 transmission, and further research is needed to evaluate their safety and efficacy in clinical settings.


Assuntos
HIV-1 , Humanos , HIV-1/genética , HIV-1/metabolismo , Antígenos CD4/genética , Antígenos CD4/química , Antígenos CD4/metabolismo , Peptídeos/farmacologia , Peptídeos/química , Sítios de Ligação , Mutação/genética , Proteína gp120 do Envelope de HIV/genética , Proteína gp120 do Envelope de HIV/farmacologia
3.
J Biomol Struct Dyn ; : 1-15, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37477254

RESUMO

Olanzapine is one of the most prescribed atypical antipsychotics to treat psychiatric illness and is associated with weight gain and metabolic disturbance. The present study investigated the olanzapine-regulated metabolic pathways using functional enrichent analysis including binding affinity with G-protein-coupled receptors (GPCRs). Proteins modulated by olanzapine were retrieved from SwissTargetPrediction, DIGEP-Pred, and BindingDB and then enriched in Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) to assess molecular function, biological process, and cellular components including Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. We used homology modeling to improve the 3D structure for GPCR synapse proteins including dopamine, serotonin, muscarinic, and histamine receptors which were then optimized using molecular dynamics (MD) simulations. The protein-olanzapine binding mechanisms for different GPCR binders were evaluated using molecular docking; later refined by MD simulations. Binding mechanism of olanzapine with D2, 5HT1A, 5HT2A, 5HT2B, 5HT2C, M1, and M2 receptors were created using homology modeling and optimized using MD simulations. In target identification, it was observed that olanzapine majority targeted G-protein coupled receptors. Further, enrichment analysis identified around 76% of the total genes regulated in molecular function, biological process, and cellular components were common including KEGG pathways. Moreover, it was observed that olanzapine had a major potency over the neurotransmitter synapse including neuroactive signals . Olanzapine-induced weight gain and metabolic alterations could be due to the deregulation of multiple synapses like dopamine, serotonin, muscarinic, and histamine at the feeding center followed by cGMP-PKG, cAMP, and PI3K-Akt signaling pathways. HIGHLIGHTSOlanzapine is used in the management of psychiatric illnesses.Olanzapine causes disturbance in lipids and glucosehomeostasis and manipulates energy expenditure.Olanzapine-induced weight gain may occur due to the deregulation of the multiple synapse and cGMP-PKG, cAMP, and PI3K-Akt signaling pathwayCommunicated by Ramaswamy H. Sarma.

4.
Front Chem ; 10: 964700, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212071

RESUMO

The rice weevil, Sitophilus oryzae (L.), is a major pest of stored grains throughout the world, which causes quantitative and qualitative losses of food commodities. Eucalyptus essential oils (EOs) possess insecticidal and repellent properties, which make them a potential option for insect control in stored grains with environmentally friendly properties. In the current study, the binding mechanism of tyramine (TA) as a control compound has been investigated by funnel metadynamics (FM) simulation toward the homology model of tyramine1 receptor (TyrR) to explore its binding mode and key residues involved in the binding mechanism. EO compounds have been extracted from the leaf and flower part of Eucalyptus camaldulensis and characterized by GC/MS, and their effectiveness has been evaluated by molecular docking and conventional molecular dynamic (CMD) simulation toward the TyrR model. The FM results suggested that Asp114 followed by Asp80, Asn91, and Asn427 are crucial residues in the binding and the functioning of TA toward TyrR in Sitophilus Oryzae. The GC/MS analysis confirmed a total of 54 and 31 constituents in leaf and flower, respectively, where most of the components (29) are common in both groups. This analysis also revealed the significant concentration of Eucalyptus and α-pinene in leaves and flower EOs. The docking followed by CMD was performed to find the most effective compound in Eucalyptus EOs. In this regard, butanoic acid, 3-methyl-, 3-methyl butyl ester (B12) and 2-Octen-1-ol, 3,7-dimethyl- (B23) from leaf and trans- ß-Ocimene (G04) from flower showed the maximum dock score and binding free energy, making them the leading candidates to replace tyramine in TyrR. The MM-PB/GBSA and MD analysis proved that the B12 structure is the most effective compound in inhibition of TyrR.

5.
Biophys Rev ; 14(1): 303-315, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35340601

RESUMO

Prostate-specific membrane antigen (PSMA), also called glutamate carboxypeptidase II (GCP(II)), is a Zn-dependent metalloprotease that is known as a well prostate cancer indication and a potential targeting towards anti-cancer medicines and drug delivery. Because of its centrality in the diagnostics and treatment of prostate cancer, several types of inhibitors are designed with particular scaffolds. In this study, important groups of related inhibitors as well as reported experimental and computational studies are being reviewed, in which we examined three functional groups on each group of structures. The importance of computational biochemistry and the necessity of extensive research in this area on PSMA and its effective ligands are recommended.

6.
Arch Biochem Biophys ; 699: 108747, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33422503

RESUMO

One of the most prevalent cancers in men is prostate cancer and could be managed with immunotoxins or antibody treatment. Because of the substantial rise of the Prostate-Specific Antigen and the Prostate-Specific Membrane Antigen (PSMA), cancer vaccination should be rendered with these antigens. Through pharmacodynamic experiments in a library of natural compounds from ZINC database, the current research sought to identify compounds that could suppress PSMA protein. To test the most productive compounds for further research, the Library has been scanned with Pharmacophore and ADMET analysis followed by molecular docking methods in the first phase. After selecting 15 ligands with the best pose related to docking results, to evaluate the stability of the ligand-protein bounds of the compounds, a molecular dynamics simulation considering the effect of the presence of zinc ions on the protein structure was performed. The measurement of ligand binding modes and free energy has shown that four compounds, including Z10, Z06, Z01, and Z03, have formed critical interactions with the active site's residues. Besides, multiple approaches were employed to determine their inhibition rating and describe the variables that facilitate the attachment of ligands to the protein active site. The results are obtained from the MMPBSA/GBSA analysis of four selected small molecules (Z10, Z06, Z01, and Z03), which are very close to the IC50 value of reference ligand (DCIBzl); they are -13.85 kcal/mol, -12.58 kcal/mol, -10.71 kcal/mol and -9.39 kcal/mol respectively. Finally, we evaluate the results obtained from selected ligands using hydrogen bond and decomposition analyzes. We have examined the effective interactions between ligands and S1/S1'pockets in protein. Our computational results illustrate the design of more efficient inhibitors of PSMA.


Assuntos
Antígenos de Superfície/metabolismo , Inibidores Enzimáticos/metabolismo , Glutamato Carboxipeptidase II/metabolismo , Glutamatos/metabolismo , Ureia/análogos & derivados , Antígenos de Superfície/química , Domínio Catalítico , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Glutamato Carboxipeptidase II/química , Glutamatos/química , Glutamatos/farmacocinética , Humanos , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Termodinâmica , Ureia/química , Ureia/metabolismo , Ureia/farmacocinética
7.
Int Med Case Rep J ; 13: 275-278, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801938

RESUMO

Chondroma is a benign tumor of mature hyaline cartilage that is often found in the long bones and may be rarely diagnosed in other parts of the body. Here, we present a young patient with the definitive diagnosis of intra-axial intracranial chondroma and without dural connection. The presenting symptoms of the patient were headache and impaired vision. The brain magnetic resonance imaging (MRI) revealed a huge enhancing parasagittal brain mass. The diagnosis was confirmed by immunohistochemistry, which was positive for S100.

8.
J Biomol Struct Dyn ; 36(15): 4126-4142, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29216799

RESUMO

Protein tyrosine phosphatase 1B (PTP1B) is a member of the PTP superfamily which is considered to be a negative regulator of insulin receptor (IR) signaling pathway. PTP1B is a promising drug target for the treatment of type 2 diabetes, obesity, and cancer. The existence of allosteric site in PTP1B has turned the researcher's attention to an alternate strategy for inhibition of this enzyme. Herein, the molecular interactions between the allosteric site of PTP1B with three non-competitive flavonoids, (MOR), (MOK), and (DPO) have been investigated. Three ligands were docked into allosteric site of the enzyme. The resulting protein-ligand complexes were used for molecular dynamics studies. Principal component and free-energy landscape (FEL) as well as cluster analyses were used to investigate the conformational and dynamical properties of the protein and identify representative enzyme substrates bounded to the inhibitors. Per residue energy decomposition analysis attributed dissimilar affinities of three inhibitors to the several hydrogen bonds and non-bonded interactions. In conclusion, our results exhibited an inhibitory pattern of the ligands against PTP1B.


Assuntos
Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Simulação de Dinâmica Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Sítio Alostérico , Humanos , Ligantes , Conformação Proteica , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo
9.
Iran J Otorhinolaryngol ; 29(92): 137-145, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28589107

RESUMO

INTRODUCTION: Cancers are among the worst noncommunicable diseases around the world. Head and neck cancers are ranked as the fifth most common cancers worldwide. As there are different distributions of risk factors around the world, the incidence of these cancers varies from one place to another. MATERIALS AND METHODS: We conducted a descriptive analytic cross-sectional study, based on census-based records from the private oncology clinic in Mashhad, Iran. Data from 1,075 patients with head and neck cancers were analyzed from 1986 to 2010. We categorized the duration of study into five periods: 1986-1990, 1991-1995, 1996-2000, 2001-2005, and 2006-2010. Head and neck cancers refers to cancers originating from seven sites in the head and neck including the nasal cavity, oral cavity, pharynx, larynx, salivary glands, paranasal sinuses, and thyroid. RESULTS: Data of 1,075 patients were analyzed. 66.2% were male. Mean ± standard deviation (SD) age at the time of diagnosis was 55.37±15.55 years. The most frequent type of head and neck cancer was larynx cancer (36%), followed by pharynx (28.5%), oral (17.5%), thyroid (6.8%), sinus (6.4%), salivary gland (4.10%), and nasal cancer (0.70%). although larynx cancer was the most frequent cancer over the whole study duration, there was a significant (P=0.04) difference in the relative frequency of these cancers across the five time periods. There was a significant difference in mean age between cancer categories (P<0.001). The only cancer with a different mean age at different time periods was pharynx cancer (P=0.02). There was a significant difference between sex and cancer categories (P<0.001). CONCLUSION: Laryngeal cancer was the most common head and neck cancer over the whole duration of this study. The differences in the patterns of other head and neck cancers could be due to geographical differences and also different risk factors and lifestyles all over the world. Further investigations in these fields are suggested in future studies.

10.
Asian Pac J Cancer Prev ; 15(23): 10193-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25556447

RESUMO

BACKGROUND: Cancer is a major cause of mortality in developing countries and correct and valid information about the epidemiology of this disease is the first step in the planning of health care in each region. The aim of this study was to determine the relative frequency, mean age and sex ratio of the most 10 common non-skin cancers in the world and Iran, among patients referred to an oncology clinic. MATERIALS AND METHODS: This descriptive study was conducted in Mashhad, north east of Iran. The data obtained from the records of patients referred to the private oncology center between the years of 1985-2012." According to the latest report of GLOBOCAN study commonest malignancies included were lung, breast, colorectal, prostate, stomach, liver, cervix, esophageal, bladder cancers and Non-Hodgkin lymphoma. RESULTS: A total of 4,606 cases were analyzed. The mean age was 55.5±13.8years (male: 59.5±13.9, female: 52.6±12.9). Overall, breast cancer (1,264 cases, relative frequency of 27.4%) was the most prevalent cancer; however the mean ages of diagnosis were not significantly different between 5-year time period divisions (p=0.290). The most common cancer in men was esophageal cancer (26.3%).The lowest mean age was related to women diagnosed with breast cancer (48.5±11.8) and men with non-Hodgkins lymphoma (48.4±17.8). There were statistically significant differences between the mean age of men and women with gastric (p=0.003) and esophageal cancers (p<0.001). Male to female sex ratios in our study for bladder, lung and stomach cancers were 6.57, 2.60 and 2.50 respectively. CONCLUSIONS: The results showed that breast cancer tends to be found in younger female patients and bladder cancer appears more often in men. Screening in target population in addition to early diagnosis may reduce death and disability.


Assuntos
Neoplasias/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Neoplasias Colorretais/epidemiologia , Neoplasias Esofágicas/epidemiologia , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Neoplasias Hepáticas/epidemiologia , Neoplasias Pulmonares/epidemiologia , Linfoma não Hodgkin/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Neoplasias da Próstata/epidemiologia , Distribuição por Sexo , Neoplasias Gástricas/epidemiologia , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Adulto Jovem
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