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1.
Int J Mol Sci ; 25(9)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38732012

RESUMO

Neuroblastoma (NB) is the most commonly diagnosed extracranial solid tumor in children, accounting for 15% of all childhood cancer deaths. Although the 5-year survival rate of patients with a high-risk disease has increased in recent decades, NB remains a challenge in pediatric oncology, and the identification of novel potential therapeutic targets and agents is an urgent clinical need. The RNA-binding protein LIN28B has been identified as an oncogene in NB and is associated with a poor prognosis. Given that LIN28B acts by negatively regulating the biogenesis of the tumor suppressor let-7 miRNAs, we reasoned that selective interference with the LIN28B/let-7 miRNA interaction would increase let-7 miRNA levels, ultimately leading to reduced NB aggressiveness. Here, we selected (-)-epigallocatechin 3-gallate (EGCG) out of 4959 molecules screened as the molecule with the best inhibitory activity on LIN28B/let-7 miRNA interaction and showed that treatment with PLC/PLGA-PEG nanoparticles containing EGCG (EGCG-NPs) led to an increase in mature let-7 miRNAs and a consequent inhibition of NB cell growth. In addition, EGCG-NP pretreatment reduced the tumorigenic potential of NB cells in vivo. These experiments suggest that the LIN28B/let-7 miRNA axis is a good therapeutic target in NB and that EGCG, which can interfere with this interaction, deserves further preclinical evaluation.


Assuntos
Catequina , MicroRNAs , Neuroblastoma , Proteínas de Ligação a RNA , Catequina/análogos & derivados , Catequina/farmacologia , Neuroblastoma/genética , Neuroblastoma/patologia , Neuroblastoma/metabolismo , Neuroblastoma/tratamento farmacológico , MicroRNAs/genética , MicroRNAs/metabolismo , Humanos , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Animais , Camundongos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Nus
2.
Appl Microbiol Biotechnol ; 108(1): 322, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713216

RESUMO

Schisandra henryi is an endemic species of medicinal potential known from traditional Chinese medicine. As part of this study, a complex biotechnological and phytochemical assessment was conducted on S. henryi with a focus on phenolic compounds and antioxidant profiling. The following in vitro cultures were tested: microshoot agar and callus, microshoot agitated, and suspension, along with the microshoot culture in PlantForm bioreactors. Qualitative profiling was performed by ultra-high-performance liquid chromatography with a photodiode array detector coupled with ion-trap mass spectrophotometry with electrospray ionization and then quantitative analysis by high-performance liquid chromatography with a diode array detector using standards. In the extracts, mainly the compounds from procyanidins were identified as well as phenolic acids (neochlorogenic acid, caffeic acid, protocatechuic acid) and catechin. The highest content of phenolic compounds was found for in vitro agar microshoot culture (max. total content 229.87 mg/100 g DW) and agitated culture (max. total content 22.82 mg/100 g DW). The max. TPC measured using the Folin-Ciocalteu assay was equal to 1240.51 mg GAE/100 g DW (agar microshoot culture). The extracts were evaluated for their antioxidant potential by the DPPH, FRAP, and chelate iron ion assays. The highest potential was indicated for agar microshoot culture (90% of inhibition and 59.31 nM/L TEAC, respectively). The research conducted on the polyphenol profiling and antioxidant potential of S. henryi in vitro culture extracts indicates the high therapeutic potential of this species. KEY POINTS: • Different types of S. henryi in vitro cultures were compared for the first time. • The S. henryi in vitro culture strong antioxidant potential was determined for the first time. • The polyphenol profiling of different types of S. henryi in vitro cultures was shown.


Assuntos
Antioxidantes , Biflavonoides , Fenóis , Extratos Vegetais , Schisandra , Antioxidantes/farmacologia , Antioxidantes/química , Fenóis/análise , Fenóis/química , Cromatografia Líquida de Alta Pressão , Schisandra/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Proantocianidinas/química , Proantocianidinas/farmacologia , Proantocianidinas/análise , Hidroxibenzoatos/análise , Hidroxibenzoatos/química , Catequina/química , Catequina/análise , Catequina/metabolismo , Catequina/farmacologia , Reatores Biológicos
3.
J Oleo Sci ; 73(5): 709-716, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38692893

RESUMO

Epigallocatechin-3-gallate (EGCG), a polyphenol derived from Green Tea, is one of the sources of natural bioactive compounds which are currently being developed as medicinal ingredients. Besides other biological activities, this natural compound exhibits anti-cariogenic effects. However, EGCG has low physical-chemical stability and poor bioavailability. Thus, the purpose of this study was to develop and characterize lipid-chitosan hybrid nanoparticle with EGCG and to evaluate its in vitro activity against cariogenic planktonic microorganisms. Lipid-chitosan hybrid nanoparticle (LCHNP-EGCG) were prepared by emulsion and sonication method in one step and characterized according to diameter, polydispersity index (PdI), zeta potential (ZP), encapsulation efficiency (EE), mucoadhesion capacity and morphology. Strains of Streptococcus mutans, Streptococcus sobrinus and Lactobacillus casei were treated with LCHNP- EGCG, and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were evaluated. LCHNP-EGCG exhibited a size of 217.3 ± 5.1 nm with a low polydispersity index (0.17) and positive zeta potential indicating the presence of chitosan on the lipid nanoparticle surface (+33.7 mV). The LCHNP-EGCG showed a spherical morphology, high stability and a mucoadhesive property due to the presence of chitosan coating. In addition, the EGCG encapsulation efficiency was 96%. A reduction of almost 15-fold in the MIC and MBC against the strains was observed when EGCG was encapsulated in LCHNP, indicating the potential of EGCG encapsulation in lipid-polymer hybrid nanoparticles. Taking the results together, the LCHNP-EGCG could be an interesting system to use in dental care due to their nanometric size, mucoadhesive properties high antibacterial activity against relevant planktonic microorganisms.


Assuntos
Antibacterianos , Catequina , Catequina/análogos & derivados , Quitosana , Testes de Sensibilidade Microbiana , Nanopartículas , Streptococcus mutans , Catequina/farmacologia , Catequina/química , Quitosana/química , Quitosana/farmacologia , Streptococcus mutans/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Nanopartículas/química , Streptococcus sobrinus/efeitos dos fármacos , Lacticaseibacillus casei/efeitos dos fármacos , Lipídeos/química , Plâncton/efeitos dos fármacos , Cárie Dentária/microbiologia , Cárie Dentária/prevenção & controle , Portadores de Fármacos/química , Tamanho da Partícula , Emulsões , Sonicação
4.
Molecules ; 29(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38731582

RESUMO

Clinicians often have to face infections caused by microorganisms that are difficult to eradicate due to their resistance and/or tolerance to antimicrobials. Among these pathogens, Pseudomonas aeruginosa causes chronic infections due to its ability to form biofilms on medical devices, skin wounds, ulcers and the lungs of patients with Cystic Fibrosis. In this scenario, the plant world represents an important reservoir of natural compounds with antimicrobial and/or antibiofilm properties. In this study, an extract from the leaves of Combretum micranthum G. Don, named Cm4-p, which was previously investigated for its antimicrobial activities, was assayed for its capacity to inhibit biofilm formation and/or to eradicate formed biofilms. The model strain P. aeruginosa PAO1 and its isogenic biofilm hyperproducer derivative B13 were treated with Cm4-p. Preliminary IR, UV-vis, NMR, and mass spectrometry analyses showed that the extract was mainly composed of catechins bearing different sugar moieties. The phytocomplex (3 g/L) inhibited the biofilm formation of both the PAO1 and B13 strains in a significant manner. In light of the obtained results, Cm4-p deserves deeper investigations of its potential in the antimicrobial field.


Assuntos
Antibacterianos , Biofilmes , Catequina , Combretum , Testes de Sensibilidade Microbiana , Extratos Vegetais , Pseudomonas aeruginosa , Biofilmes/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antibacterianos/farmacologia , Antibacterianos/química , Catequina/farmacologia , Catequina/química , Combretum/química , Folhas de Planta/química , Açúcares , Humanos
5.
Food Chem ; 449: 139166, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38604025

RESUMO

Apostichopus japonicus (A. japonicus) has rich nutritional value and is an important economic crop. Due to its rich endogenous enzyme system, fresh A. japonicus is prone to autolysis during market circulation and storage, resulting in economic losses. In order to alleviate this phenomenon, we investigated the effect of polyphenol oxidase (PPO) mediated (-)-epigallocatechin gallate (EGCG) on the activity and structure of endogenous cathepsin series protein (CEP) from A. japonicus. Research on cathepsin activity showed that PPO mediated EGCG could significantly reduce enzyme activity, resulting in a decrease in enzymatic reaction rate. SDS-PAGE and scanning electron microscopy results showed that PPO mediates EGCG could induce CEP aggregation to form protein aggregates. Various spectral results indicated that EGCG caused changes in the structure of CEP. Meanwhile, the conjugates formed by PPO mediated EGCG had lower thermal stability. In conclusion, PPO mediated EGCG was an effective method to inhibit the endogenous enzyme activity.


Assuntos
Catequina , Catequina/análogos & derivados , Catecol Oxidase , Catepsinas , Stichopus , Catequina/química , Catequina/farmacologia , Catecol Oxidase/metabolismo , Catecol Oxidase/química , Animais , Stichopus/enzimologia , Stichopus/química , Catepsinas/metabolismo , Catepsinas/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Estabilidade Enzimática , Cinética
6.
Int Immunopharmacol ; 133: 112069, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38643710

RESUMO

Epigallocatechin-3-gallate (EGCG) is an important tea polyphenol with anti-tumor potential. Our previous studies revealed that EGCG was a promising immune checkpoint inhibitor (ICI) as it could downregulate expression of programmed cell death 1 ligand 1 (PD-L1) in tumor cells, thereby resulting tumor killing effect. In particular, EGCG can effectively avoid the inflammatory storm caused by anti-tumor therapy, which is a healthy green capacity absent from many ICIs. However, the relationship between EGCG and programmed cell death 1 (PD-1) of T cells remains unclear. In this work, we explored the effect of EGCG on T cells and found that EGCG suppressed PD-1 via inhibiting NF-κB phosphorylation and nuclear translocation. Furtherly, the capability of EGCG was confirmed in tumor-bearing mice to inhibit PD-1 expression in T cells and enhance apoptosis in tumor cells. These results implied that EGCG could inhibit the expression of PD-1 in T cells, thereby promoting anti-tumor effects of T cells. EGCG will be a promising candidate in anti-tumor therapy.


Assuntos
Catequina , NF-kappa B , Receptor de Morte Celular Programada 1 , Linfócitos T , Catequina/análogos & derivados , Catequina/farmacologia , Animais , Receptor de Morte Celular Programada 1/metabolismo , Receptor de Morte Celular Programada 1/antagonistas & inibidores , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Camundongos , Humanos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Feminino , Núcleo Celular/metabolismo , Núcleo Celular/efeitos dos fármacos , Transporte Ativo do Núcleo Celular/efeitos dos fármacos
7.
Bioconjug Chem ; 35(5): 682-692, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38648296

RESUMO

The delivery of proteins into the cytosol holds great promise for cell signaling manipulation and the development of precision medicine. However, this potency is challenged by achieving targeted and controlled delivery, specifically within diseased cells. In this study, we introduce a versatile and effective method for the precision delivery of therapeutic proteins to cancer cells by designing polyphenol-assisted biomineralization of zeolite imidazole framework-8 (ZIF-8). We demonstrate that by leveraging the strong noncovalent binding affinity of epigallocatechin gallate (EGCG) with both proteins and ZIF-8, our approach significantly enhances the biomineralization of ZIF-8, which in turn improves the efficiency of protein encapsulation and intracellular delivery. Moreover, the incorporation of EGCG within ZIF-8 enables controlled degradation of the nanoparticles and the selective release of the encapsulated proteins in cancer cells. This selective release is triggered by the oxidation of EGCG in response to the high levels of reactive oxygen species (ROS) found within cancer cells that destabilize the EGCG/ZIF-8 nanoparticles. We have further demonstrated the ability of EGCG/ZIF-8 to deliver a wide range of proteins into cancer cells, including bacterial virulence protein, to rewire cell signaling and prohibit tumor cell growth in a mouse xenograft model. Our strategy and findings underscore the potential of designing the EGCG/ZIF-8 interface for specific and controlled protein delivery for targeted cancer therapy.


Assuntos
Catequina , Estruturas Metalorgânicas , Nanopartículas , Polifenóis , Humanos , Estruturas Metalorgânicas/química , Polifenóis/química , Polifenóis/farmacologia , Animais , Nanopartículas/química , Catequina/análogos & derivados , Catequina/química , Catequina/administração & dosagem , Catequina/farmacologia , Camundongos , Zeolitas/química , Biomineralização , Imidazóis/química , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Espécies Reativas de Oxigênio/metabolismo
8.
BMC Cancer ; 24(1): 486, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632501

RESUMO

BACKGROUND: The antiviral drug Nirmatrelvir was found to be a key drug in controlling the progression of pneumonia during the infectious phase of COVID-19. However, there are very few options for effective treatment for cancer patients who have viral pneumonia. Glucocorticoids is one of the effective means to control pneumonia, but there are many adverse events. EGCG is a natural low toxic compound with anti-inflammatory function. Thus, this study was designed to investigate the safety and efficacy of epigallocatechin-3-gallate (EGCG) aerosol to control COVID-19 pneumonia in cancer populations. METHODS: The study was designed as a prospective, single-arm, open-label phase I/II trial at Shandong Cancer Hospital and Institute, between January 5, 2023 to March 31,2023 with viral pneumonia on radiographic signs after confirmed novel coronavirus infection. These patients were treated with EGCG nebulization 10 ml three times daily for at least seven days. EGCG concentrations were increased from 1760-8817umol/L to 4 levels with dose escalation following a standard Phase I design of 3-6 patients per level. Any grade adverse event caused by EGCG was considered a dose-limiting toxicity (DLT). The maximum tolerated dose (MTD) is defined as the highest dose with less than one-third of patients experiencing dose limiting toxicity (DLT) due to EGCG. The primary end points were the toxicity of EGCG and CT findings, and the former was graded by Common Terminology Criteria for Adverse Events (CTCAE) v. 5.0. The secondary end point was the laboratory parameters before and after treatment. RESULT: A total of 60 patients with high risk factors for severe COVID-19 pneumonia (factors such as old age, smoking and combined complications)were included in this phase I-II study. The 54 patients in the final analysis were pathologically confirmed to have tumor burden and completed the whole course of treatment. A patient with bucking at a level of 1760 umol/L and no acute toxicity associated with EGCG has been reported at the second or third dose gradients. At dose escalation to 8817umol/L, Grade 1 adverse events of nausea and stomach discomfort occurred in two patients, which resolved spontaneously within 1 hour. After one week of treatment, CT showed that the incidence of non-progression of pneumonia was 82% (32/39), and the improvement rate of pneumonia was 56.4% (22/39). There was no significant difference in inflammation-related laboratory parameters (white blood cell count, lymphocyte count, IL-6, ferritin, C-reactive protein and lactate dehydrogenase) before and after treatment. CONCLUSION: Aerosol inhalation of EGCG is well tolerated, and preliminary investigation in cancer population suggests that EGCG may be effective in COVID-19-induced pneumonia, which can promote the improvement of patients with moderate pneumonia or prevent them from developing into severe pneumonia. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05758571. Date of registration: 8 February 2023.


Assuntos
COVID-19 , Catequina/análogos & derivados , Neoplasias , Pneumonia Viral , Humanos , Oxigênio , Estudos Prospectivos , Pneumonia Viral/epidemiologia , Resultado do Tratamento , Aerossóis e Gotículas Respiratórios
9.
Int J Pharm ; 656: 124095, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38588757

RESUMO

Reactive oxygen species (ROS) play a vital role in wound healing process by fighting against invaded bacteria. However, excess ROS at the wound sites lead to oxidative stress that can trigger deleterious effects, causing cell death, tissue damage and chronic inflammation. Therefore, we fabricated a core-shell structured nanomedicine with antibacterial and antioxidant properties via a facile and green strategy. Specifically, Prussian blue (PB) nanozyme was fabricated and followed by coating a layer of epigallocatechin-3-gallate (EGCG)-derived polymer via polyphenolic condensation reaction and self-assembly process, resulting in PB@EGCG. The introduction of PB core endowed EGCG-based polyphenol nanoparticles with excellent NIR-triggered photothermal properties. Besides, owing to multiple enzyme-mimic activity of PB and potent antioxidant capacity of EGCG-derived polymer, PB@EGCG exhibited a remarkable ROS-scavenging ability, mitigated intracellular ROS level and protected cells from oxidative damage. Under NIR irradiation (808 nm, 1.5 W/cm2), PB@EGCG (50 µg/mL) exerted synergistic EGCG-derived polymer-photothermal antibacterial activity against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). In vivo therapeutic effect was evaluated using a S. aureus-infected rat model indicated PB@EGCG with a prominent bactericidal ability could modulate the inflammatory microenvironment and accelerate wound healing. Overall, this dual-functional nanomedicine provides a promising strategy for efficient antibacterial therapy.


Assuntos
Antibacterianos , Antioxidantes , Catequina , Catequina/análogos & derivados , Escherichia coli , Ferrocianetos , Nanopartículas , Polímeros , Espécies Reativas de Oxigênio , Staphylococcus aureus , Catequina/química , Catequina/farmacologia , Catequina/administração & dosagem , Ferrocianetos/química , Animais , Espécies Reativas de Oxigênio/metabolismo , Antibacterianos/farmacologia , Antibacterianos/administração & dosagem , Antibacterianos/química , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Ratos , Polímeros/química , Nanopartículas/química , Antioxidantes/farmacologia , Antioxidantes/administração & dosagem , Antioxidantes/química , Masculino , Ratos Sprague-Dawley , Humanos , Infecções Estafilocócicas/tratamento farmacológico , Camundongos , Terapia Fototérmica/métodos , Estresse Oxidativo/efeitos dos fármacos
10.
Drug Des Devel Ther ; 18: 1115-1131, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38618280

RESUMO

Background: The ChaiShao Shugan Formula (CSSGF) is a traditional Chinese medicine formula with recently identified therapeutic value in triple-negative breast cancer (TNBC). This study aimed to elucidate the underlying mechanism of CSSGF in TNBC treatment. Methods: TNBC targets were analyzed using R and data were from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. The major ingredients and related protein targets of CSSGF were explored via the Traditional Chinese Medicine Systems Pharmacology database, and an ingredient-target network was constructed via Cytoscape to identify hub genes. The STRING database was used to construct the PPI network. GO and KEGG enrichment analyses were performed via R to obtain the main targets. The online tool Kaplan‒Meier plotter was used to identify the prognostic genes. Molecular docking was applied to the core target genes and active ingredients. MDA-MB-231 and MCF-7 cell lines were used to verify the efficacy of the various drugs. Results: A total of 4562 genes were screened as TNBC target genes. The PPI network consisted of 89 nodes and 845 edges. Our study indicated that quercetin, beta-sitosterol, luteolin and catechin might be the core ingredients of CSSGF, and EGFR and c-Myc might be the latent therapeutic targets of CSSGF in the treatment of TNBC. GO and KEGG analyses indicated that the anticancer effect of CSSGF on TNBC was mainly associated with DNA binding, transcription factor binding, and other biological processes. The related signaling pathways mainly involved the TNF-a, IL-17, and apoptosis pathways. The molecular docking data indicated that quercetin, beta-sitosterol, luteolin, and catechin had high affinity for EGFR, JUN, Caspase-3 and ESR1, respectively. In vitro, we found that CSSGF could suppress the expression of c-Myc or promote the expression of EGFR. In addition, we found that quercetin downregulates c-Myc expression in two BC cell lines. Conclusion: This study revealed the effective ingredients and latent molecular mechanism of action of CSSGF against TNBC and confirmed that quercetin could target c-Myc to induce anti-BC effects.


Assuntos
Catequina , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Luteolina , Simulação de Acoplamento Molecular , Quercetina , Células MCF-7 , Receptores ErbB/genética
11.
Food Chem ; 448: 139140, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38574720

RESUMO

Theabrownins (TBs) are heterogeneous mixtures of water-soluble brown tea pigments, and important constituents to evaluate the quality of dark tea. TBs have numerous hydroxyl and carboxyl groups and are formed by the oxidative polymerization of tea polyphenols. Many biological activities attributed to TBs, including antioxidant, anti-obesity, and lipid-regulating, have been demonstrated. This review summarizes the research progress made on the formation mechanism and physicochemical properties of TBs. It also discusses their protective effects against various diseases and associated potential molecular mechanisms. Additionally, it examines the signaling pathways mediating the bioactivities of TBs and highlights the difficulties and challenges of TBs research as well as their research prospects and applications.


Assuntos
Antioxidantes , Humanos , Antioxidantes/química , Animais , Camellia sinensis/química , Chá/química , Polifenóis/química , Polifenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Catequina/química , Fármacos Antiobesidade/química , Fármacos Antiobesidade/farmacologia
12.
J Nutr Sci Vitaminol (Tokyo) ; 70(2): 164-173, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38684387

RESUMO

Bitterness and astringency are the aversive tastes in mammals. In humans, aversion to bitterness and astringency may be reduced depending on the eating experience. However, the cellular and molecular mechanisms underlying plasticity in preference to bitter and astringent tastants remain unknown. This study aimed to investigate the preference plasticity to bitter and astringent tea polyphenols, including catechins and tannic acids, in the model animal Caenorhabditis elegans. C. elegans showed avoidance behavior against epigallocatechin gallate (EGCG), tannic acid, and theaflavin. However, they displayed diminishing avoidance against EGCG depending on their EGCG-feeding regime at larval stages. Additionally, the behavioral plasticity in avoiding EGCG required the transcription factor DAF-16/FOXO. Isoform-specific deletion mutant analysis and cell-specific rescue analysis revealed that the function of daf-16 isoform b in AIY interneurons is necessary for experience-dependent behavioral plasticity to EGCG.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Catequina , Fatores de Transcrição Forkhead , Interneurônios , Animais , Catequina/análogos & derivados , Catequina/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Fatores de Transcrição Forkhead/metabolismo , Interneurônios/efeitos dos fármacos , Interneurônios/metabolismo , Aprendizagem da Esquiva/efeitos dos fármacos , Biflavonoides/farmacologia , Paladar/efeitos dos fármacos , Chá/química , Comportamento Animal/efeitos dos fármacos , Larva/efeitos dos fármacos
13.
Nutrients ; 16(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38613003

RESUMO

The ingestion of dietary cocoa flavanols acutely alters functions of the cerebral endothelium, but whether the effects of flavanols permeate beyond this to alter other brain functions remains unclear. Based on converging evidence, this work tested the hypothesis that cocoa flavanols would alter brain excitability in young healthy adults. In a randomised, cross-over, double-blinded, placebo-controlled design, transcranial magnetic stimulation was used to assess corticospinal and intracortical excitability before as well as 1 and 2 h post-ingestion of a beverage containing either high (695 mg flavanols, 150 mg (-)-epicatechin) or low levels (5 mg flavanols, 0 mg (-)-epicatechin) of cocoa flavanols. In addition to this acute intervention, the effects of a short-term chronic intervention where the same cocoa flavanol doses were ingested once a day for 5 consecutive days were also investigated. For both the acute and chronic interventions, the results revealed no robust alteration in corticospinal or intracortical excitability. One possibility is that cocoa flavanols yield no net effect on brain excitability, but predominantly alter functions of the cerebral endothelium in young healthy adults. Future studies should increase intervention durations to maximize the acute and chronic accumulation of flavanols in the brain, and further investigate if cocoa flavanols would be more effective at altering brain excitability in older adults and clinical populations than in younger adults.


Assuntos
Cacau , Catequina , Chocolate , Humanos , Idoso , Catequina/farmacologia , Alimentos , Encéfalo , Polifenóis
14.
PLoS One ; 19(4): e0301904, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38662666

RESUMO

Our previous research demonstrated that PU.1 regulates expression of the genes involved in inflammation in macrophages. Selective knockdown of PU.1 in macrophages ameliorated LPS-induced acute lung injury (ALI) in bone marrow chimera mice. Inhibitors that block the transcriptional activity of PU.1 in macrophages have the potential to mitigate the pathophysiology of LPS-induced ALI. However, complete inactivation of PU.1 gene disrupts normal myelopoiesis. Although the green tea polyphenol Epigallocatechin gallate (EGCG) has been shown to regulate inflammatory genes in various cell types, it is not known if EGCG alters the transcriptional activity of PU.1 protein. Using Schrodinger Glide docking, we have identified that EGCG binds with PU.1 protein, altering its DNA-binding and self-dimerization activity. In silico analysis shows that EGCG forms Hydrogen bonds with Glutamic Acid 209, Leucine 250 in DNA binding and Lysine 196, Tryptophan 193, and Leucine 182 in the self-dimerization domain of the PU.1 protein. Experimental validation using mouse bone marrow-derived macrophages (BMDM) confirmed that EGCG inhibits both DNA binding by PU.1 and self-dimerization. Importantly, EGCG had no impact on expression of the total PU.1 protein levels but significantly reduced expression of various inflammatory genes and generation of ROS. In summary, we report that EGCG acts as an inhibitor of the PU.1 transcription factor in macrophages.


Assuntos
Catequina , Catequina/análogos & derivados , Macrófagos , Proteínas Proto-Oncogênicas , Transativadores , Catequina/farmacologia , Animais , Transativadores/metabolismo , Transativadores/genética , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/genética , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Ligação Proteica , DNA/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/farmacologia
15.
Biomed Res Int ; 2024: 1741539, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628498

RESUMO

Background: Dental implantation has become a standard procedure with high success rates, relying on achieving osseointegration between the implant surface and surrounding bone tissue. Polyether ether ketone (PEEK) is a promising alternative to traditional dental implant materials like titanium, but its osseointegration capabilities are limited due to its hydrophobic nature and reduced surface roughness. Objective: The aim of the study is to increase the surface roughness and hydrophilicity of PEEK by treating the surface with piranha solution and then coating the surface with epigallocatechin-3-gallate (EGCG) by electrospraying technique. Materials and Methods: The study includes four groups intended to investigate the effect of piranha treatment and EGCG coating: a control group of PEEK discs with no treatment (C), PEEK samples treated with piranha solution (P), a group of PEEK samples coated with EGCG (E), and a group of PEEK samples treated with piranha solution and coated with EGCG (PE). Surface roughness, wettability, and microhardness were assessed through statistical analysis. Results: Piranha treatment increased surface roughness, while EGCG coating moderated it, resulting in an intermediate roughness in the PE group. EGCG significantly improved wettability, as indicated by the reduced contact angle. Microhardness increased by about 20% in EGCG-coated groups compared to noncoated groups. Statistical analysis confirmed significant differences between groups in all tests. Conclusion: This study demonstrates the potential of EGCG coating to enhance the surface properties of PEEK as dental implants. The combined piranha and EGCG modification approach shows promise for improved osseointegration, although further vivo research is necessary. Surface modification techniques hold the key to optimizing biomaterial performance, bridging the gap between laboratory findings and clinical implementation in dental implantology.


Assuntos
Catequina/análogos & derivados , Polietilenoglicóis , Polímeros , Polímeros/química , Polietilenoglicóis/química , Benzofenonas , Cetonas/farmacologia , Cetonas/química , Propriedades de Superfície , Éteres , Titânio/química
16.
Int J Biol Macromol ; 267(Pt 2): 131496, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38626839

RESUMO

We aimed to study the potential of epigallocatechin-3-gallate/tyrosol-loaded chitosan/lecithin nanoparticles (EGCG/tyrosol-loaded C/L NPs) in streptozotocin-induced type 2 diabetes mellitus (T2DM) mice. The EGCG/tyrosol-loaded C/L NPs were created using the self-assembly method. Dynamic light scattering, Field Emission Scanning Electron Microscopy, and Fourier transform infrared spectroscopy were utilized to characterize the nanoparticle. Furthermore, in streptozotocin-induced T2DM mice, treatment with EGCG/tyrosol-loaded C/L NPs on fasting blood sugar levels, the expression of PCK1 and G6Pase, and IL-1ß in the liver, liver glutathione content, nanoparticle toxicity on liver cells, and liver reactive oxygen species were measured. Our findings showed that EGCG/tyrosol-loaded C/L NPs had a uniform size distribution, and encapsulation efficiencies of 84 % and 89.1 % for tyrosol and EGCG, respectively. The nanoparticles inhibited PANC-1 cells without affecting normal HFF cells. Furthermore, EGCG/tyrosol-loaded C/L NP treatment reduced fasting blood sugar levels, elevated hepatic glutathione levels, enhanced liver cell viability, and decreased reactive oxygen species levels in diabetic mice. The expression of gluconeogenesis-related genes (PCK1 and G6 Pase) and the inflammatory gene IL-1ß was downregulated by EGCG/tyrosol-loaded C/L NPs. In conclusion, the EGCG/tyrosol-loaded C/L NPs reduced hyperglycemia, oxidative stress, and inflammation in diabetic mice. These findings suggest that EGCG/tyrosol-loaded C/L NPs could be a promising therapeutic option for type 2 diabetes management.


Assuntos
Catequina , Quitosana , Diabetes Mellitus Experimental , Hiperglicemia , Fígado , Nanopartículas , Animais , Quitosana/química , Catequina/análogos & derivados , Catequina/farmacologia , Catequina/administração & dosagem , Diabetes Mellitus Experimental/tratamento farmacológico , Nanopartículas/química , Camundongos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Hiperglicemia/tratamento farmacológico , Masculino , Glicemia , Estreptozocina , Espécies Reativas de Oxigênio/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Glutationa/metabolismo
17.
Biochem Biophys Res Commun ; 714: 149976, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38677007

RESUMO

BACKGROUND: The systemic treatment of advanced hepatocellular carcinoma is currently facing a bottleneck. EGCG, the primary active compound in green tea, exhibits anti-tumor effects through various pathways. However, there is a lack of study on EGCG-induced immunogenic cell death (ICD) in hepatocellular carcinoma. METHODS: In a previous study, we successfully synthesized folate-modified thermosensitive nano-materials, encapsulated EGCG within nanoparticles using a hydration method, and established the EGCG nano-drug delivery system. The viability of HepG2 cells post-EGCG treatment was assessed via the MTT and EdU assays. Cell migration and invasion were evaluated through wound healing experiments, Transwell assays, and Annexin V-FITC/PI assay for apoptosis detection. Additionally, the expression levels of damage-associated molecular patterns (DAMPs) were determined using immunofluorescence, ATP measurement, RT-qPCR, and Western Blot. RESULTS: The drug sensitivity test revealed an IC50 value of 96.94 µg/mL for EGCG in HepG2 cells after 48 h. EGCG at a low concentration (50 µg/mL) significantly impeded the migration and invasion of HepG2 cells, showing a clear dose-dependent response. Moreover, medium to high EGCG concentrations induced cell apoptosis in a dose-dependent manner and upregulated DAMPs expression. Immunofluorescence analysis demonstrated a notable increase in CRT expression following low-concentration EGCG treatment. As EGCG concentration increased, cell viability decreased, leading to CRT exposure on the cell membrane. EGCG also notably elevated ATP levels. RT-qPCR and Western Blot analyses indicated elevated expression levels of HGMB1, HSP70, and HSP90 following EGCG intervention. CONCLUSION: EGCG not only hinders the proliferation, migration, and invasion of hepatocellular carcinoma cells and induces apoptosis, but also holds significant clinical promise in the treatment of malignant tumors by promoting ICD and DAMPs secretion.


Assuntos
Carcinoma Hepatocelular , Catequina , Catequina/análogos & derivados , Ácido Fólico , Neoplasias Hepáticas , Humanos , Catequina/farmacologia , Catequina/química , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Células Hep G2 , Ácido Fólico/química , Ácido Fólico/farmacologia , Movimento Celular/efeitos dos fármacos , Morte Celular Imunogênica/efeitos dos fármacos , Nanosferas/química , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Temperatura , Calreticulina/metabolismo
18.
Food Chem ; 449: 139279, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38599106

RESUMO

The aim of this study was to prepare protein-polyphenol covalent complexes by treating egg yolk granules (EYG) with alkali in the presence of epigallocatechin gallate (EGCG) and characterize the physicochemical, structural, and functional properties of these covalent complexes. Results revealed that the optimal covalent binding occurred when the concentration of EGCG reached 0.15% (w/w), resulting in a grafting rate of 1.51 ± 0.03%. As the amount of EGCG increased, corresponding increases were observed in the particle size and ζ-potential of the complexes, thereby enhancing their stability. Furthermore, our analysis using fluorescence spectroscopy, FTIR, SEM, and SDS-PAGE collectively demonstrated the formation of a covalent complex between EYG and EGCG. Notably, the covalent complexes exhibited improved antioxidant activity and emulsifying properties. Overall, this study establishes a theoretical framework for the future practical application of EYG, emphasizing the potential of EGCG to modify its structural and functional characteristics.


Assuntos
Antioxidantes , Catequina , Catequina/análogos & derivados , Gema de Ovo , Catequina/química , Gema de Ovo/química , Animais , Antioxidantes/química , Tamanho da Partícula , Galinhas
19.
J Agric Food Chem ; 72(12): 6327-6338, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38484116

RESUMO

The present work aimed to characterize the phenolic and antioxidant content of the Argentinian purple maize "Moragro" cultivar. Additionally, the INFOGEST simulated in vitro digestion model was used to establish the effect of digestion on bioactive compounds. Finally, digestion samples were used to treat Caco-2 cells in the transwell model to better understand their bioavailability. Twenty-six phenolic compounds were found in purple maize cv. "Moragro", 15 nonanthocyanins and 11 anthocyanins. Several compounds were identified in maize for the first time, such as pyrogallol, citric acid, gallic acid, kaempferol 3-(6″-ferulylglucoside), and kaempferol 3-glucuronide. Anthocyanins accounted for 24.9% of total polyphenols, with the predominant anthocyanin being cyanidin-3-(6″ malonylglucoside). Catechin-(4,8)-cyanidin-3,5-diglucoside and catechin-(4,8)-cyanidin-3-malonylglucoside-5-glucoside were detected as characteristics of this American maize variety. Total polyphenol content (TPC; by the Folin-Ciocalteu method), HPLC-DAD/MSMS, and antioxidant activity [by DPPH and ferric-reducing antioxidant power (FRAP)] were evaluated throughout in vitro digestion. TPC, DPPH, and FRAP results were 2.71 mg gallic acid equivalents (GAE)/g, 24 µmol Trolox equiv/g, and 22 µmol Trolox eq/g, respectively. The in vitro digestion process did not cause significant differences in TPC. However, the antioxidant activity was significantly decreased. Moreover, the bioavailability of anthocyanins was studied, showing that a small fraction of polyphenols in their intact form was conserved at the end of digestion. Finally, a protective effect of digested maize polyphenols was observed in the Caco-2 cell viability. The results suggest that "Moragro" purple maize is a good source of bioavailable anthocyanins in the diet and an interesting source of this group of compounds for the food industry.


Assuntos
Antocianinas , Catequina , Humanos , Antocianinas/química , Zea mays/química , Antioxidantes , Células CACO-2 , Quempferóis , Cromatografia Líquida de Alta Pressão , Fenóis/química , Polifenóis/análise , Ácido Gálico , Digestão
20.
Acta Pharm ; 74(1): 81-99, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38554388

RESUMO

This study aims to assess the chemical composition of the aqueous extract of Cistus albidus L. leaves, as well as the potential of aqueous and hydroethanol extracts of the leaves and seeds as analgesic, anti--inflammatory, and antioxidant agents. The contents of phenolics and inorganic constituents were determined in C. albidus seeds and leaves; antioxidant capacity was assessed by 3 complementary and diverse tests. The carrageenan-induced paw edema technique was used to investigate the anti-inflammatory effect in vivo, and albumin denaturation to evaluate the anti-inflammatory effect in vitro. The acetic acid-induced contortion test, the tail-flick test, and the plantar test were used to assess the analgesic effi cacy in vivo. Chemical analysis was performed by UPLC-MS/MS to quantify several phenolic compounds including catechin (1,627.6 mg kg-1), quercitrin (1,235.8 mg kg-1) and gallic acid (628. 2 mg kg-1). The ICP analysis revealed that potassium and calcium were the main inorganic components in the seeds and leaves of C. albidus. The hydroethanolic extract of the leaves showed the highest content of polyphenols/flavonoids, whereas the highest value of proantho cyanidins was detected in the aqueous extract of the seeds. All extracts showed potent antioxidant activity related to different phenolic compounds (quercetin, gallic acid, astragalin, catechin, and rutin). The aqueous extract of the leaves strongly inhibited paw edema (76.1 %) after 6 h of treatment and showed maximal inhibition of protein denaturation (191.0 µg mL-1 for 50 % inhibition) and analgesic activity in different nociceptive models. The presented data reveal that C. albidus extracts potentially show antioxidant, anti-inflammatory, and analgesic activities that could confirm the traditional use of this plant.


Assuntos
Catequina , Cistus , Antioxidantes/análise , Cistus/química , Cromatografia Líquida , Catequina/efeitos adversos , Catequina/análise , Extratos Vegetais/química , Dor/induzido quimicamente , Dor/tratamento farmacológico , Espectrometria de Massas em Tandem , Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Fenóis/farmacologia , Ácido Gálico/efeitos adversos , Ácido Gálico/análise , Edema/induzido quimicamente , Edema/tratamento farmacológico , Folhas de Planta/química
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