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1.
Bioorg Chem ; 143: 106987, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38039927

RESUMEN

Secreted proteins play critical roles in regulating immune responses, exerting cytotoxic effects on tumor cells, promoting inflammatory processes, and influencing cellular metabolism. Deciphering the intricate relationship between the heterogeneity of secreted proteins and their transcriptional states is pivotal in the study of cellular heterogeneity. Here we proposed a cell-antibody conjugate-based sequencing methodology (Cellab-seq) for joint characterization of secreted proteins and transcriptome. Cellab-seq utilizes a chemoenzymatic strategy to construct cell-antibody conjugates, which enables the capture of secreted proteins and their signal transduction with the incorporation of barcode detection antibodies. We applied Cellab-seq to investigate how gene expression influences the activity of secreted proteins in NK cells. Altogether, this strategy facilitates a nuanced understanding of cellular dynamics under diverse physiological conditions, ultimately contributing to the prevention, diagnosis and treatment of diseases.


Asunto(s)
Células Asesinas Naturales , Transcriptoma
2.
Int J Mol Sci ; 25(2)2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38255913

RESUMEN

Dipeptidyl peptidase 4 (DPP4) inhibitors can effectively inhibit the activity of DPP4, increasing the concentrations of glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), which allows for them to effectively contribute to the reduction of blood sugar levels. Leu-Pro-Ala-Val-Thr-Ile-Arg (LPAVTIR) and Leu-Pro-Pro-Glu-His-Asp-Trp-Arg (LPPEHDWR) were the two peptides with the strongest inhibitory activity against DPP4 selected from silkworm pupa proteins. In this study, four systems were established: Apo (ligand-free DPP4), IPI (IPI-bound DPP4), LPAVTIR (LPAVTIR-bound DPP4), LPPEHDWR (LPPEHDWR-bound DPP4), and Gaussian accelerated molecular dynamic (GaMD) simulation was conducted to investigate the mechanism of action of two inhibitory peptides binding to DPP4. Our study revealed that the LPAVTIR peptide possessed a more stable structure and exhibited a tighter binding to the Ser630 active site in DPP4, thus exhibiting a favorable competitive inhibition effect. In contrast, the LPPEHDWR peptide caused the horizontal α-helix (residues 201-215) composed of Glu205 and Glu206 residues in DPP4 to disappear. The spatial arrangement of active sites Ser630 relative to Glu205 and Glu206 was disrupted, resulting in enzyme inactivation. Moreover, the size of the substrate channel and cavity volume was significantly reduced after the binding of the inhibitory peptide to the protein, which was an important factor in the inhibition of the enzyme activity. A similar effect was also found from IPI (our positive control). By stabilizing the active site of DPP4, the IPI peptide induced the disappearance of the horizontal α-helix and a notable reduction in the active cavity volume. In conclusion, our study provided a solid theoretical foundation for the inhibitory mechanisms of IPI, LPAVTIR, and LPPEHDWR on DPP4, offering valuable insights for advancing the development of drug targets for type 2 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Humanos , Dipeptidil Peptidasa 4 , Simulación de Dinámica Molecular , Péptidos/farmacología , Inhibidores de la Dipeptidil-Peptidasa IV/farmacología
3.
Int J Mol Sci ; 25(6)2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38542486

RESUMEN

Fresh green leaves give off a smell known as "green odor." It has antibacterial qualities and can be used to attract or repel insects. However, a common method for evaluating green odor molecules has never existed. Machine learning techniques are widely used in research to forecast molecular attributes for binary classification. In this work, the green odor molecules were first trained and learned using machine learning methods, and then clustering analysis and molecular docking were performed to further explore their molecular characteristics and mechanisms of action. For comparison, four algorithmic models were employed, MLP performed the best in all metrics, including Accuracy, Precision, Average Precision, Matthews coefficient, and Area under curve. We determined by difference analysis that, in comparison to non-green odor molecules, green odor molecules have a lower molecular mass and fewer electrons. Based on the MLP algorithm, we constructed a binary classification prediction website for green odors. The first application of deep learning techniques to the study of green odor molecules can be seen as a signal of a new era in which green odor research has advanced into intelligence and standardization.


Asunto(s)
Odorantes , Olfato , Simulación del Acoplamiento Molecular , Algoritmos , Aprendizaje Automático
4.
Int J Mol Sci ; 25(7)2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38612466

RESUMEN

Type 2 diabetes mellitus (T2DM) is marked by persistent hyperglycemia, insulin resistance, and pancreatic ß-cell dysfunction, imposing substantial health burdens and elevating the risk of systemic complications and cardiovascular diseases. While the pathogenesis of diabetes remains elusive, a cyclical relationship between insulin resistance and inflammation is acknowledged, wherein inflammation exacerbates insulin resistance, perpetuating a deleterious cycle. Consequently, anti-inflammatory interventions offer a therapeutic avenue for T2DM management. In this study, a herb called Baikal skullcap, renowned for its repertoire of bioactive compounds with anti-inflammatory potential, is posited as a promising source for novel T2DM therapeutic strategies. Our study probed the anti-diabetic properties of compounds from Baikal skullcap via network pharmacology, molecular docking, and cellular assays, concentrating on their dual modulatory effects on diabetes through Protein Tyrosine Phosphatase 1B (PTP1B) enzyme inhibition and anti-inflammatory actions. We identified the major compounds in Baikal skullcap using liquid chromatography-mass spectrometry (LC-MS), highlighting six flavonoids, including the well-studied baicalein, as potent inhibitors of PTP1B. Furthermore, cellular experiments revealed that baicalin and baicalein exhibited enhanced anti-inflammatory responses compared to the active constituents of licorice, a known anti-inflammatory agent in TCM. Our findings confirmed that baicalin and baicalein mitigate diabetes via two distinct pathways: PTP1B inhibition and anti-inflammatory effects. Additionally, we have identified six flavonoid molecules with substantial potential for drug development, thereby augmenting the T2DM pharmacotherapeutic arsenal and promoting the integration of herb-derived treatments into modern pharmacology.


Asunto(s)
Diabetes Mellitus Tipo 2 , Flavanonas , Resistencia a la Insulina , Scutellaria baicalensis , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Cromatografía Líquida con Espectrometría de Masas , Cromatografía Liquida , Simulación del Acoplamiento Molecular , Espectrometría de Masas en Tándem , Flavonoides/farmacología , Inflamación , Antiinflamatorios/farmacología
5.
Int J Mol Sci ; 25(7)2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38612872

RESUMEN

Recently, studies have reported a correlation that individuals with diabetes show an increased risk of developing Alzheimer's disease (AD). Mulberry leaves, serving as both a traditional medicinal herb and a food source, exhibit significant hypoglycemic and antioxidative properties. The flavonoid compounds in mulberry leaf offer therapeutic effects for relieving diabetic symptoms and providing neuroprotection. However, the mechanisms of this effect have not been fully elucidated. This investigation aimed to investigate the combined effects of specific mulberry leaf flavonoids (kaempferol, quercetin, rhamnocitrin, tetramethoxyluteolin, and norartocarpetin) on both type 2 diabetes mellitus (T2DM) and AD. Additionally, the role of the gut microbiota in these two diseases' treatment was studied. Using network pharmacology, we investigated the potential mechanisms of flavonoids in mulberry leaves, combined with gut microbiota, in combating AD and T2DM. In addition, we identified protein tyrosine phosphatase 1B (PTP1B) as a key target for kaempferol in these two diseases. Molecular docking and molecular dynamics simulations showed that kaempferol has the potential to inhibit PTP1B for indirect treatment of AD, which was proven by measuring the IC50 of kaempferol (279.23 µM). The cell experiment also confirmed the dose-dependent effect of kaempferol on the phosphorylation of total cellular protein in HepG2 cells. This research supports the concept of food-medicine homology and broadens the range of medical treatments for diabetes and AD, highlighting the prospect of integrating traditional herbal remedies with modern medical research.


Asunto(s)
Enfermedad de Alzheimer , Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Morus , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Quempferoles , Simulación de Dinámica Molecular , Farmacología en Red , Enfermedad de Alzheimer/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Frutas , Flavonoides
6.
Int J Mol Sci ; 24(21)2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37958916

RESUMEN

There are reports indicating that licochalcones can inhibit the proliferation, migration, and invasion of cancer cells by promoting the expression of autophagy-related proteins, inhibiting the expression of cell cycle proteins and angiogenic factors, and regulating autophagy and apoptosis. This study aims to reveal the potential mechanisms of licochalcone A (LCA), licochalcone B (LCB), licochalcone C (LCC), licochalcone D (LCD), licochalcone E (LCE), licochalcone F (LCF), and licochalcone G (LCG) inhibition in liver cancer through computer-aided screening strategies. By using machine learning clustering analysis to search for other structurally similar components in licorice, quantitative calculations were conducted to collect the structural commonalities of these components related to liver cancer and to identify key residues involved in the interactions between small molecules and key target proteins. Our research results show that the seven licochalcones molecules interfere with the cancer signaling pathway via the NF-κB signaling pathway, PDL1 expression and PD1 checkpoint pathway in cancer, and others. Glypallichalcone, Echinatin, and 3,4,3',4'-Tetrahydroxy-2-methoxychalcone in licorice also have similar structures to the seven licochalcones, which may indicate their similar effects. We also identified the key residues (including ASN364, GLY365, TRP366, and TYR485) involved in the interactions between ten flavonoids and the key target protein (nitric oxide synthase 2). In summary, we provide valuable insights into the molecular mechanisms of the anticancer effects of licorice flavonoids, providing new ideas for the design of small molecules for liver cancer drugs.


Asunto(s)
Chalconas , Neoplasias Hepáticas , Humanos , Farmacología en Red , Chalconas/farmacología , Chalconas/química , Flavonoides , FN-kappa B , Neoplasias Hepáticas/tratamiento farmacológico
7.
Int J Mol Sci ; 24(19)2023 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-37833919

RESUMEN

The disease of SARS-CoV-2 has caused considerable morbidity and mortality globally. Spike proteins on the surface of SARS-CoV-2 allow it to bind with human cells, leading to infection. Fullerenes and their derivatives are promising SARS-CoV-2 inhibitors and drug-delivery vehicles. In this study, Gaussian accelerated molecular dynamics simulations and the Markov state model were employed to delve into the inhibitory mechanism of Fullerene-linear-polyglycerol-b-amine sulfate (F-LGPS) on spike proteins. During the study, it was discovered that fullerene derivatives can operate at the interface of the receptor-binding domain (RBD) and the N-terminal domain (NTD), keeping structural domains in a downward conformation. It was also observed that F-LGPS demonstrated superior inhibitory effects on the XBB variant in comparison to the wild-type variant. This study yielded invaluable insights for the potential development of efficient therapeutics targeting the spike protein of SARS-CoV-2.


Asunto(s)
COVID-19 , Fulerenos , Humanos , SARS-CoV-2 , Fulerenos/farmacología , Glicoproteína de la Espiga del Coronavirus , Simulación de Dinámica Molecular , Unión Proteica
8.
Molecules ; 28(13)2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37446803

RESUMEN

To explore the anti-hyperuricemia components in sunflower (Helianthus annuus L.) calathide extract (SCE), we identified abietic acid (AA) via liquid chromatography-mass spectrometry and found an excellent inhibitor of xanthine oxidase (IC50 = 10.60 µM, Ki = 193.65 nM) without cytotoxicity. Based on the transcriptomics analysis of the human embryonic kidney 293T cell model established using 1 mM uric acid, we evaluated that AA showed opposite modulation of purine metabolism to the UA group and markedly suppressed the intensity of purine nucleoside phosphorylase, ribose phosphate pyrophosphokinase 2, and ribose 5-phosphate isomerase A. Molecular docking also reveals the inhibition of purine nucleoside phosphorylase and ribose phosphate pyrophosphokinase 1. The SCE exhibits similar regulation of these genes, so we conclude that AA was a promising component in SCE against hyperuricemia. This present study provided a novel cell model for screening anti-hyperuricemia natural drugs in vitro and illustrated that AA, a natural diterpenoid, is a potential inhibitor of purine biosynthesis or metabolism.


Asunto(s)
Helianthus , Hiperuricemia , Humanos , Helianthus/metabolismo , Purina-Nucleósido Fosforilasa/metabolismo , Simulación del Acoplamiento Molecular , Ribosa-Fosfato Pirofosfoquinasa/metabolismo , Células HEK293 , Hiperuricemia/tratamiento farmacológico , Hiperuricemia/metabolismo , Riñón/metabolismo , Purinas/metabolismo , Xantina Oxidasa
9.
Angew Chem Int Ed Engl ; 62(28): e202303014, 2023 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-37165969

RESUMEN

Intercellular proximity labeling has emerged as a promising approach to enable the study of cell-cell interactions (CCIs), but the efficiency of current platforms is limited. Here, we use Ru(bpy)3 2+ to construct an efficient photocatalytic proximity labeling (PPL) system on the cell surface that allows the highly discriminative CCI detection with spatiotemporal resolution. Through the mechanism study and quantitative characterization on living cells, we demonstrate that the singlet-oxygen (1 O2 ) mechanism is more efficient and specific than the single electron transfer (SET) mechanism in Ru-mediated PPL. Ru(bpy)3 2+ catalysts with different cell-anchoring moieties are prepared to facilitate the catalyst loading on primary cells. Finally, based on this system, we develop a "live" T cell receptor (TCR) multimer with TCR-T cells that could sensitively identify and discriminate cells presenting antigens of different affinity, providing a powerful tool to better understand the heterogeneity of antigen presenting cells.

10.
Int J Mol Sci ; 23(22)2022 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-36430160

RESUMEN

Anticancer peptide (ACP) is a short peptide with less than 50 amino acids that has been discovered in a variety of foods. It has been demonstrated that traditional Chinese medicine or food can help treat cancer in some cases, which suggests that ACP may be one of the therapeutic ingredients. Studies on the anti-cancer properties of Sanghuangporus sanghuang have concentrated on polysaccharides, flavonoids, triterpenoids, etc. The function of peptides has not received much attention. The purpose of this study is to use computer mining techniques to search for potential anticancer peptides from 62 proteins of Sanghuang. We used mACPpred to perform sequence scans after theoretical trypsin hydrolysis and discovered nine fragments with an anticancer probability of over 0.60. The study used AlphaFold 2 to perform structural modeling of the first three ACPs discovered, which had blast results from the Cancer PPD database. Using reverse docking technology, we found the target proteins and interacting residues of two ACPs with an unknown mechanism. Reverse docking results predicted the binding modes of the ACPs and their target protein. In addition, we determined the active part of ACPs by quantum chemical calculation. Our study provides a framework for the future discovery of functional peptides from foods. The ACPs discovered have the potential to be used as drugs in oncology clinical treatment after further research.


Asunto(s)
Antineoplásicos , Neoplasias , Triterpenos , Humanos , Antineoplásicos/uso terapéutico , Péptidos/química , Neoplasias/tratamiento farmacológico , Proteínas/uso terapéutico , Triterpenos/uso terapéutico
11.
Molecules ; 26(21)2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34770898

RESUMEN

Human dipeptidyl-peptidase III (hDPP III) is capable of specifically cleaving dipeptides from the N-terminal of small peptides with biological activity such as angiotensin II (Ang II, DRVYIHPF), and participates in blood pressure regulation, pain modulation, and the development of cancers in human biological activities. In this study, 500 ns molecular dynamics simulations were performed on free-hDPP III (PDB code: 5E33), hDPP III-Ang II (PDB code: 5E2Q), and hDPP III-IVYPW (PDB code: 5E3C) to explore how these two peptides affect the catalytic efficiency of enzymes in terms of the binding mode and the conformational changes. Our results indicate that in the case of the hDPP III-Ang II complex, subsite S1 became small and hydrophobic, which might be propitious for the nucleophile to attack the substrate. The structures of the most stable conformations of the three systems revealed that Arg421-Lys423 could form an α-helix with the presence of Ang II, but only part of the α-helix was produced in hDPP III-IVYPW. As the hinge structure in hDPP III, the conformational changes that took place in the Arg421-Lys423 residue could lead to the changes in the shape and space of the catalytic subsites, which might allow water to function as a nucleophile to attack the substrate. Our results may provide new clues to enable the design of new inhibitors for hDPP III in the future.


Asunto(s)
Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/química , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Sitios de Unión , Catálisis , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/metabolismo , Humanos , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Ligandos , Inhibidores de Proteasas/química , Inhibidores de Proteasas/farmacología , Unión Proteica , Conformación Proteica , Relación Estructura-Actividad , Especificidad por Sustrato
12.
Molecules ; 26(2)2021 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-33466694

RESUMEN

This study was focused on extraction, radical scavenging activities, and chemical composition identification of total flavonoids in sunflower (Helianthus annuus L.) receptacles (TFSR). We investigated the optimal extract parameters of TFSR using response surface methodology. The highest yield of TFSR was 1.04% with the ethanol concentration 58%, the material-to-liquid ratio 1:20 (v/w), the extraction time 2.6 h, and the extraction temperature 67 °C. The results of radical scavenging activities showed that ethyl acetate fraction (EAF) was the strongest by using 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2'-azino-bis (3-ethylbenzo thiazoline-6-sulfonic acid) (ABTS) and iron ion reducing analysis. The EAF had the highest flavonoids contents. Four fractions A, B, C and D were enrichment from EAF by polyamide resin. Fraction B had the highest flavonoids content. Thirteen chemical components of flavonoids in fraction B were first identified by Ultimate 3000 Nano LC System coupled to a Q Exactive HF benchtop Orbitrap mass spectrometer (UHPLC-HRMS/MS). Among of the thirteen chemical components, isoquercetin and daidzein were identified accurately by comparing with standard samples. Radical scavenging analysis showed that isoquercetin and EAF had strong activities. Therefore, sunflower receptacles can be used as a source of natural flavonoids. TFSR as a natural radical scavenger has potential applications in pharmaceutical industry.


Asunto(s)
Acetatos/química , Antioxidantes/farmacología , Flavonoides/química , Flavonoides/farmacología , Depuradores de Radicales Libres/farmacología , Helianthus/química , Extractos Vegetales/farmacología , Flavonoides/aislamiento & purificación
13.
Molecules ; 25(22)2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-33187052

RESUMEN

Sunflower (Helianthus annuus L.) contains active ingredients, such as flavonoids, alkaloids and tannins. Nevertheless, few studies have focused on essential oil from the receptacle of sunflower (SEO). In this work, we investigated the chemical composition and antimicrobial and antioxidant activities of SEO. The yield of SEO was about 0.42% (v/w) by hydrodistillation. A total of 68 volatile components of SEO were putatively identified by gas chromatography-mass spectrometry (GC-MS). The main constituents of SEO were α-pinene (26.00%), verbenone (7.40%), terpinolene (1.69%) and α-terpineol (1.27%). The minimum inhibitory concentration (MIC) of SEO against P. aeruginosa and S. aureus was 0.2 mg/mL. The MIC of SEO against S. cerevisiae was 3.2 mg/mL. The MIC of SEO against E. coli and Candida albicans was 6.4 mg/mL. The results showed that SEO had high antibacterial and antifungal activities. Three different analytical assays (DPPH, ABTS and iron ion reducing ability) were used to determine the antioxidant activities. The results showed that SEO had antioxidant activities. To summarize, the results in this study demonstrate the possibility for the development and application of SEO in potential natural preservatives and medicines due to its excellent antimicrobial and antioxidant activities.


Asunto(s)
Antibacterianos/química , Antioxidantes/química , Helianthus/química , Aceites Volátiles/química , Aceites de Plantas/química , Antibacterianos/farmacología , Antifúngicos/química , Antifúngicos/farmacología , Antioxidantes/farmacología , Monoterpenos Bicíclicos/química , Candida albicans/efectos de los fármacos , Monoterpenos Ciclohexánicos/química , Escherichia coli/efectos de los fármacos , Depuradores de Radicales Libres/farmacología , Radicales Libres , Cromatografía de Gases y Espectrometría de Masas , Humanos , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/efectos de los fármacos , Saccharomyces cerevisiae/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos
14.
Arch Gynecol Obstet ; 293(2): 421-7, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26264810

RESUMEN

PURPOSE: To identify key genes related to the effect of estrogen on ovarian cancer. METHODS: Microarray data (GSE22600) were downloaded from Gene Expression Omnibus. Eight estrogen and seven placebo treatment samples were obtained using a 2 × 2 factorial designs, which contained 2 cell lines (PEO4 and 2008) and 2 treatments (estrogen and placebo). Differentially expressed genes were identified by Bayesian methods, and the genes with P < 0.05 and |log2FC (fold change)| ≥0.5 were chosen as cut-off criterion. Differentially co-expressed genes (DCGs) and differentially regulated genes (DRGs) were, respectively, identified by DCe function and DRsort function in DCGL package. Topological structure analysis was performed on the important transcriptional factors (TFs) and genes in transcriptional regulatory network using tYNA. Functional enrichment analysis was, respectively, performed for DEGs and the important genes using Gene Ontology and KEGG databases. RESULTS: In total, 465 DEGs were identified. Functional enrichment analysis of DEGs indicated that ACVR2B, LTBP1, BMP7 and MYC involved in TGF-beta signaling pathway. The 2285 DCG pairs and 357 DRGs were identified. Topological structure analysis showed that 52 important TFs and 65 important genes were identified. Functional enrichment analysis of the important genes showed that TP53 and MLH1 participated in DNA damage response and the genes (ACVR2B, LTBP1, BMP7 and MYC) involved in TGF-beta signaling pathway. CONCLUSION: TP53, MLH1, ACVR2B, LTBP1 and BMP7 might participate in the pathogenesis of ovarian cancer.


Asunto(s)
Estrógenos/metabolismo , Regulación Neoplásica de la Expresión Génica , Análisis por Micromatrices/métodos , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Factores de Transcripción/genética , Teorema de Bayes , Biología Computacional , Femenino , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Factor de Crecimiento Transformador beta
15.
Protein Expr Purif ; 107: 7-12, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25462809

RESUMEN

Osteoclastic protein tyrosine phosphatase (PTP-oc) is a structurally unique transmembrane protein tyrosine phosphatase (PTP) that contains only a relatively small intracellular PTP catalytic domain, does not have an extracellular domain, and lacks a signal peptide proximal to the NH2 terminus. The present study reports the expression, purification, and characterization of the intracellular catalytic domain of PTP-oc (ΔPTP-oc). ΔPTP-oc was expressed in Escherichia coli cells as a fusion with a six-histidine tag and was purified via nickel affinity chromatography. When with para-nitrophenylphosphate (p-NPP) as a substrate, ΔPTP-oc exhibited classical Michaelis-Menten kinetics. Its responses to temperature and ionic strength were similar to those of other PTPs. The optimal pH value of ΔPTP-oc is approximately 7.0, unlike other PTPs, whose optimal pH values are approximately 5.0.


Asunto(s)
Expresión Génica , Osteoclastos/enzimología , Proteínas Tirosina Fosfatasas/química , Proteínas Tirosina Fosfatasas/aislamiento & purificación , Secuencia de Aminoácidos , Dominio Catalítico , Estabilidad de Enzimas , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Cinética , Osteoclastos/química , Proteínas Tirosina Fosfatasas/genética , Proteínas Tirosina Fosfatasas/metabolismo
16.
Pak J Pharm Sci ; 27(6): 1905-10, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25362614

RESUMEN

The inhibition of 3-hydroxy-3-methylglutaryl CoA reductase (HMGCR) is considered able to decrease serum cholesterol levels and dramatically reduce the risk for cardiovascular and cerebrovascular diseases. The statins, competitive inhibitors of HMGCR, have been employed to control hypercholesterolemia. But their side effects, especially their safety of long-term administration have attracted great attention. Therefore, there is still an urgent requirement for the development of safer inhibitors of HMGCR with less serious side effects. In this study, we cloned and purified the catalytic domain of human HMGCR (△HMGCR), and applied the method of Ultra Performance Liquid Chromatography (UPLC) to assay △HMGCR activity and screen its inhibitors from natural products. The results indicated that EGCG can inhibit △HMGCR in the presence of some glycerol in vitro and can decrease cellular total cholesterol in HepG2 cells. As a consequence, it is promising to put EGCG into the development of hypolipidemic health product.


Asunto(s)
Catequina/análogos & derivados , Glicerol/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Catequina/farmacología , Células Hep G2 , Humanos
17.
Comput Biol Med ; 179: 108814, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38944902

RESUMEN

Peptides, with recognized physiological and medical implications, such as the ability to lower blood pressure and lipid levels, are central to our research on umami taste perception. This study introduces a computational strategy to tackle the challenge of identifying optimal umami receptors for these peptides. Our VmmScore algorithm includes two integral components: Mlp4Umami, a predictive module that evaluates the umami taste potential of peptides, and mm-Score, which enhances the receptor matching process through a machine learning-optimized molecular docking and scoring system. This system encompasses the optimization of docking structures, clustering of umami peptides, and a comparative analysis of docking energies across peptide clusters, streamlining the receptor identification process. Employing machine learning, our method offers a strategic approach to the intricate task of umami receptor determination. We undertook virtual screening of peptides derived from Lateolabrax japonicus, experimentally verifying the umami taste of three identified peptides and determining their corresponding receptors. This work not only advances our understanding of the mechanisms behind umami taste perception but also provides a rapid and cost-effective method for peptide screening. The source code is publicly accessible at https://github.com/heyigacu/mlp4umami/, encouraging further scientific exploration and collaborative efforts within the research community.

18.
Int J Biol Macromol ; 268(Pt 2): 131902, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38692532

RESUMEN

Vitamin B12 is a group of biologically active cobalamin compounds. In this study, we investigated the inhibitory effects of methylcobalamin (MeCbl) and hydroxocobalamin acetate (OHCbl Acetate) on protein tyrosine phosphatase 1B (PTP1B). MeCbl and OHCbl Acetate exhibited an IC50 of approximately 58.390 ± 2.811 µM and 8.998 ± 0.587 µM, respectively. The Ki values of MeCbl and OHCbl Acetate were 25.01 µM and 4.04 µM respectively. To elucidate the inhibition mechanism, we conducted a 500 ns Gaussian accelerated molecular dynamics (GaMD) simulation. Utilizing PCA and tICA, we constructed Markov state models (MSM) to examine secondary structure changes during motion. Our findings revealed that the α-helix at residues 37-42 remained the most stable in the PTP1B-OHCbl Acetate system. Furthermore, upon binding of OHCbl Acetate or MeCbl, the WPD loop of PTP1B moved inward to the active pocket, forming a closed conformation and potentially obstructs substrate entry. Protein-ligand interaction analysis and MM-PBSA showed that OHCbl Acetate exhibited lower binding free energy and engaged in more residue interactions with PTP1B. In summary, our study confirmed the substantial inhibitory activity of OHCbl Acetate against PTP1B, with its inhibitory potency notably surpassing that of MeCbl. We demonstrated potential molecular mechanisms of OHCbl Acetate inhibiting PTP1B.


Asunto(s)
Simulación de Dinámica Molecular , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , Vitamina B 12 , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Proteína Tirosina Fosfatasa no Receptora Tipo 1/química , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Vitamina B 12/química , Vitamina B 12/análogos & derivados , Vitamina B 12/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Humanos , Simulación del Acoplamiento Molecular , Unión Proteica , Cinética , Relación Estructura-Actividad
19.
Sci Rep ; 14(1): 174, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38168773

RESUMEN

Xanthine oxidase (XO) is a crucial enzyme in the development of hyperuricemia and gout. This study focuses on LWM and ALPM, two food-derived inhibitors of XO. We used molecular docking to obtain three systems and then conducted 200 ns molecular dynamics simulations for the Apo, LWM, and ALPM systems. The results reveal a stronger binding affinity of the LWM peptide to XO, potentially due to increased hydrogen bond formation. Notable changes were observed in the XO tunnel upon inhibitor binding, particularly with LWM, which showed a thinner, longer, and more twisted configuration compared to ALPM. The study highlights the importance of residue F914 in the allosteric pathway. Methodologically, we utilized the perturbed response scan (PRS) based on Python, enhancing tools for MD analysis. These findings deepen our understanding of food-derived anti-XO inhibitors and could inform the development of food-based therapeutics for reducing uric acid levels with minimal side effects.


Asunto(s)
Aprendizaje Profundo , Hiperuricemia , Humanos , Xantina Oxidasa , Relación Estructura-Actividad , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Inhibidores Enzimáticos/química , Hiperuricemia/tratamiento farmacológico , Péptidos/farmacología , Péptidos/uso terapéutico
20.
Comput Biol Med ; 177: 108598, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38776729

RESUMEN

In this study, our focus was on investigating H-1,2,3-triazole derivative HP661 as a novel and highly efficient oral OXPHOS inhibitor, with its molecular-level inhibitory mechanism not yet fully understood. We selected the ND1, NDUFS2, and NDUFS7 subunits of Mitochondrial Complex I as the receptor proteins and established three systems for comparative analysis: protein-IACS-010759, protein-lead compound 10, and protein-HP661. Through extensive analysis involving 500 ns Gaussian molecular dynamics simulations, we gained insights into these systems. Additionally, we constructed a Markov State Models to examine changes in secondary structures during the motion processes. The research findings suggest that the inhibitor HP661 enhances the extensibility and hydrophilicity of the receptor protein. Furthermore, HP661 induces the unwinding of the α-helical structure in the region of residues 726-730. Notably, key roles were identified for Met37, Phe53, and Pro212 in the binding of various inhibitors. In conclusion, we delved into the potential molecular mechanisms of triazole derivative HP661 in inhibiting Complex I. These research outcomes provide crucial information for a deeper understanding of the mechanisms underlying OXPHOS inhibition, offering valuable theoretical support for drug development and disease treatment design.


Asunto(s)
Complejo I de Transporte de Electrón , Cadenas de Markov , Simulación de Dinámica Molecular , Complejo I de Transporte de Electrón/antagonistas & inhibidores , Complejo I de Transporte de Electrón/química , Complejo I de Transporte de Electrón/metabolismo , Humanos , Triazoles/química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Administración Oral
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