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1.
Plant J ; 118(6): 1793-1814, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38461478

RESUMO

Flavan-3-ols are prominent phenolic compounds found abundantly in the young leaves of tea plants. The enzymes involved in flavan-3-ol biosynthesis in tea plants have been extensively investigated. However, the localization and associations of these numerous functional enzymes within cells have been largely neglected. In this study, we aimed to investigate the synthesis of flavan-3-ols in tea plants, particularly focusing on epigallocatechin gallate. Our analysis involving the DESI-MSI method to reveal a distinct distribution pattern of B-ring trihydroxylated flavonoids, primarily concentrated in the outer layer of buds. Subcellular localization showed that CsC4H, CsF3'H, and CsF3'5'H localizes endoplasmic reticulum. Protein-protein interaction studies demonstrated direct associations between CsC4H, CsF3'H, and cytoplasmic enzymes (CHS, CHI, F3H, DFR, FLS, and ANR), highlighting their interactions within the biosynthetic pathway. Notably, CsF3'5'H, the enzyme for B-ring trihydroxylation, did not directly interact with other enzymes. We identified cytochrome b5 isoform C serving as an essential redox partner, ensuring the proper functioning of CsF3'5'H. Our findings suggest the existence of distinct modules governing the synthesis of different B-ring hydroxylation compounds. This study provides valuable insights into the mechanisms underlying flavonoid diversity and efficient synthesis and enhances our understanding of the substantial accumulation of B-ring trihydroxylated flavan-3-ols in tea plants.


Assuntos
Camellia sinensis , Catequina , Citocromos b5 , Flavonoides , Proteínas de Plantas , Flavonoides/metabolismo , Flavonoides/biossíntese , Camellia sinensis/metabolismo , Camellia sinensis/genética , Catequina/metabolismo , Catequina/análogos & derivados , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Citocromos b5/metabolismo , Citocromos b5/genética , Folhas de Planta/metabolismo , Hidroxilação , Retículo Endoplasmático/metabolismo
2.
Arterioscler Thromb Vasc Biol ; 44(7): 1674-1682, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38752350

RESUMO

BACKGROUND: A series of incurable cardiovascular disorders arise due to improper formation of elastin during development. Supravalvular aortic stenosis (SVAS), resulting from a haploinsufficiency of ELN, is caused by improper stress sensing by medial vascular smooth muscle cells, leading to progressive luminal occlusion and heart failure. SVAS remains incurable, as current therapies do not address the root issue of defective elastin. METHODS: We use SVAS here as a model of vascular proliferative disease using both human induced pluripotent stem cell-derived vascular smooth muscle cells and developmental Eln+/- mouse models to establish de novo elastin assembly as a new therapeutic intervention. RESULTS: We demonstrate mitigation of vascular proliferative abnormalities following de novo extracellular elastin assembly through the addition of the polyphenol epigallocatechin gallate to SVAS human induced pluripotent stem cell-derived vascular smooth muscle cells and in utero to Eln+/- mice. CONCLUSIONS: We demonstrate de novo elastin deposition normalizes SVAS human induced pluripotent stem cell-derived vascular smooth muscle cell hyperproliferation and rescues hypertension and aortic mechanics in Eln+/- mice, providing critical preclinical findings for the future application of epigallocatechin gallate treatment in humans.


Assuntos
Estenose Aórtica Supravalvular , Catequina , Proliferação de Células , Modelos Animais de Doenças , Elastina , Células-Tronco Pluripotentes Induzidas , Músculo Liso Vascular , Miócitos de Músculo Liso , Elastina/metabolismo , Animais , Humanos , Catequina/análogos & derivados , Catequina/farmacologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Estenose Aórtica Supravalvular/metabolismo , Estenose Aórtica Supravalvular/genética , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Músculo Liso Vascular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Camundongos , Células Cultivadas , Camundongos Endogâmicos C57BL , Feminino , Masculino , Camundongos Knockout
3.
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
4.
Small ; 20(26): e2310604, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38329190

RESUMO

Nanoparticle-based drug delivery strategies have emerged as a crucial avenue for comprehensive sensorineural hearing loss treatment. Nevertheless, developing therapy vectors crossing both biological and cellular barriers has encountered significant challenges deriving from various external factors. Herein, the rational integration of gelatin nanoparticles (GNPs) with tetrahedral DNA nanostructures (TDNs) to engineer a distinct drug-delivery nanosystem (designed as TDN@GNP) efficiently enhances the biological permeability and cellular internalization, further resolving the dilemma of noise-induced hearing loss via loading epigallocatechin gallate (EGCG) with anti-lipid peroxidation property. Rationally engineering of TDN@GNP demonstrates dramatic alterations in the physicochemical key parameters of TDNs that are pivotal in cell-particle interactions and promote cellular uptake through multiple endocytic pathways. Furthermore, the EGCG-loaded nanosystem (TDN-EGCG@GNP) facilitates efficient inner ear drug delivery by superior permeability through the biological barrier (round window membrane), maintaining high drug concentration within the inner ear. The TDN-EGCG@GNP actively overcomes the cell membrane, exhibiting hearing protection from noise insults via reduced lipid peroxidation in outer hair cells and spiral ganglion neurons. This work exemplifies how integrating diverse vector functionalities can overcome biological and cellular barriers in the inner ear, offering promising applications for inner ear disorders.


Assuntos
Catequina , DNA , Gelatina , Perda Auditiva Provocada por Ruído , Nanoestruturas , Gelatina/química , DNA/química , DNA/metabolismo , Perda Auditiva Provocada por Ruído/metabolismo , Perda Auditiva Provocada por Ruído/tratamento farmacológico , Animais , Nanoestruturas/química , Catequina/análogos & derivados , Catequina/química , Catequina/farmacologia , Camundongos , Peroxidação de Lipídeos/efeitos dos fármacos , Nanopartículas/química , Sistemas de Liberação de Medicamentos
5.
Small ; : e2311967, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38712482

RESUMO

Intracellular bacteria pose a great challenge to antimicrobial therapy due to various physiological barriers at both cellular and bacterial levels, which impede drug penetration and intracellular targeting, thereby fostering antibiotic resistance and yielding suboptimal treatment outcomes. Herein, a cascade-target bacterial-responsive drug delivery nanosystem, MM@SPE NPs, comprising a macrophage membrane (MM) shell and a core of SPE NPs. SPE NPs consist of phenylboronic acid-grafted dendritic mesoporous silica nanoparticles (SP NPs) encapsulated with epigallocatechin-3-gallate (EGCG), a non-antibiotic antibacterial component, via pH-sensitive boronic ester bonds are introduced. Upon administration, MM@SPE NPs actively home in on infected macrophages due to the homologous targeting properties of the MM shell, which is subsequently disrupted during cellular endocytosis. Within the cellular environment, SPE NPs expose and spontaneously accumulate around intracellular bacteria through their bacteria-targeting phenylboronic acid groups. The acidic bacterial microenvironment further triggers the breakage of boronic ester bonds between SP NPs and EGCG, allowing the bacterial-responsive release of EGCG for localized intracellular antibacterial effects. The efficacy of MM@SPE NPs in precisely eliminating intracellular bacteria is validated in two rat models of intracellular bacterial infections. This cascade-targeting responsive system offers new solutions for treating intracellular bacterial infections while minimizing the risk of drug resistance.

6.
Cancer Cell Int ; 24(1): 200, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840243

RESUMO

Ferroptosis, an iron-dependent regulated cell death mechanism, holds significant promise as a therapeutic strategy in oncology. In the current study, we explored the regulatory effects of epigallocatechin gallate (EGCG), a prominent polyphenol in green tea, on ferroptosis and its potential therapeutic implications for non-small cell lung cancer (NSCLC). Treatment of NSCLC cell lines with varying concentrations of EGCG resulted in a notable suppression of cell proliferation, as evidenced by a reduction in Ki67 immunofluorescence staining. Western blot analyses demonstrated that EGCG treatment led to a decrease in the expression of glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11) while increasing the levels of acyl-CoA synthetase long-chain family member 4 (ACSL4). These molecular changes were accompanied by an increase in intracellular iron, malondialdehyde (MDA), and reactive oxygen species (ROS), alongside ultrastructural alterations characteristic of ferroptosis. Through small RNA sequencing and RT-qPCR, transfer RNA-derived small RNA 13502 (tsRNA-13502) was identified as a significant target of EGCG action, with its expression being upregulated in NSCLC tissues compared to adjacent non-tumorous tissues. EGCG was found to modulate the ferroptosis pathway by downregulating tsRNA-13502 and altering the expression of key ferroptosis regulators (GPX4/SLC7A11 and ACSL4), thereby promoting the accumulation of iron, MDA, and ROS, and ultimately inducing ferroptosis in NSCLC cells. This study elucidates EGCG's multifaceted mechanisms of action, underscoring the modulation of ferroptosis as a viable therapeutic approach for enhancing NSCLC treatment outcomes.

7.
Pharmacol Res ; 203: 107179, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38615876

RESUMO

Exosomes, small yet vital extracellular vesicles, play an integral role in intercellular communication. They transport critical components, such as proteins, lipid bilayers, DNA, RNA, and glycans, to target cells. These vesicles are crucial in modulating the extracellular matrix and orchestrating signal transduction processes. In oncology, exosomes are pivotal in tumor growth, metastasis, drug resistance, and immune modulation within the tumor microenvironment. Exosomal proteins, noted for their stability and specificity, have garnered widespread attention. This review delves into the mechanisms of exosomal protein loading and their impact on tumor development, with a focus on the regulatory effects of natural products and traditional Chinese medicine on exosomal protein loading and function. These insights not only offer new strategies and methodologies for cancer treatment but also provide scientific bases and directions for future clinical applications.


Assuntos
Produtos Biológicos , Exossomos , Medicina Tradicional Chinesa , Neoplasias , Humanos , Exossomos/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Animais , Produtos Biológicos/uso terapêutico , Produtos Biológicos/farmacologia , Microambiente Tumoral/efeitos dos fármacos
8.
Pharmacol Res ; 203: 107150, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521285

RESUMO

Cancer, with its diversity, heterogeneity, and complexity, is a significant contributor to global morbidity, disability, and mortality, highlighting the necessity for transformative treatment approaches. Photodynamic therapy (PDT) has aroused continuous interest as a viable alternative to conventional cancer treatments that encounter drug resistance. Nanotechnology has brought new advances in medicine and has shown great potential in drug delivery and cancer treatment. For precise and efficient therapeutic utilization of such a tumor therapeutic approach with high spatiotemporal selectivity and minimal invasiveness, the carrier-free noncovalent nanoparticles (NPs) based on chemo-photodynamic combination therapy is essential. Utilizing natural products as the foundation for nanodrug development offers unparalleled advantages, including exceptional pharmacological activity, easy functionalization/modification, and well biocompatibility. The natural-product-based, carrier-free, noncovalent NPs revealed excellent synergistic anticancer activity in comparison with free photosensitizers and free bioactive natural products, representing an alternative and favorable combination therapeutic avenue to improve therapeutic efficacy. Herein, a comprehensive summary of current strategies and representative application examples of carrier-free noncovalent NPs in the past decade based on natural products (such as paclitaxel, 10-hydroxycamptothecin, doxorubicin, etoposide, combretastatin A4, epigallocatechin gallate, and curcumin) for tumor chemo-photodynamic combination therapy. We highlight the insightful design and synthesis of the smart carrier-free NPs that aim to enhance PDT efficacy. Meanwhile, we discuss the future challenges and potential opportunities associated with these NPs to provide new enlightenment, spur innovative ideas, and facilitate PDT-mediated clinical transformation.


Assuntos
Produtos Biológicos , Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Animais , Neoplasias/tratamento farmacológico , Nanopartículas/química , Produtos Biológicos/química , Produtos Biológicos/uso terapêutico , Produtos Biológicos/farmacologia , Produtos Biológicos/administração & dosagem , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/administração & dosagem
9.
Metab Brain Dis ; 39(2): 347-357, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37721652

RESUMO

Ischemic stroke is a leading cause of disability and death in patients. Despite considerable recent advances in the treatment of ischemic stroke, only a limited number of effective neuroprotective agents are available for stroke. Green tea (Camellia sinensis) is a popular herbal plant, and numerous studies have indicated its health benefits for several diseases. Green tea is of interest due to its high content of catechin derivatives, including epicatechin, gallocatechin, epicatechin gallate, epigallocatechin, and epigallocatechin-3-gallate. This review tried to develop a feasible background for the potential effects of green tea and its bioactive derivatives concerning protection against ischemic stroke. Green tea's antioxidants, anti-inflammatory, anti-apoptotic, and neuroprotective effects are believed to be efficacious in stroke treatment. Evidence supports the idea that green tea can be used to assist in treating ischemic stroke.


Assuntos
Camellia sinensis , AVC Isquêmico , Humanos , Chá , Camellia sinensis/química , AVC Isquêmico/tratamento farmacológico , Antioxidantes , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química
10.
J Appl Toxicol ; 44(5): 686-698, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38095138

RESUMO

To evaluate the oral toxicity of nanoparticles (NPs), it is necessary to consider the interactions between NPs and nutrient molecules. Recently, we reported that epigallocatechin gallate (EGCG), a healthy component in green tea, alleviated the toxicity of ZnO NPs to 3D Caco-2 spheroids in vitro. The present study investigated the combined effects of EGCG and ZnO NPs to mice in vivo. Mice were administrated with 35 or 105 mg/kg bodyweight ZnO NPs with or without the presence of 80 mg/kg bodyweight EGCG via gastric route, once a day, for 21 days, and the influences of EGCG on the toxicity of ZnO NPs to intestine were investigated. We found that EGCG altered the colloidal properties of ZnO NPs both in water and artificial intestine juice. As expected, ZnO NPs induced toxicological effects, such as decreased bodyweight, higher Chiu's scores, and ultrastructural changes in intestine, whereas EGCG alleviated these effects. Combined exposure to EGCG and ZnO NPs also changed trace element levels in mouse intestine. For example, the levels of Ti, Co, and Ni were only significantly elevated after co-exposure to EGCG and ZnO NPs, and Fe levels were only significantly decreased by ZnO NPs. Western blot analysis suggested that tight junction (TJ) and endoplasmic reticulum (ER) proteins were elevated by ZnO NPs, but EGCG inhibited this trend. Combined, these data suggested that gastric exposure to ZnO NPs induced intestinal damage, trace element imbalance, and TJ/ER protein expression in mouse intestine, whereas EGCG alleviated these effects of ZnO NPs.


Assuntos
Catequina/análogos & derivados , Nanopartículas , Oligoelementos , Óxido de Zinco , Humanos , Camundongos , Animais , Óxido de Zinco/toxicidade , Óxido de Zinco/química , Células CACO-2 , Nanopartículas/toxicidade , Nanopartículas/química
11.
Luminescence ; 39(3): e4727, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38527806

RESUMO

Green tea extract (GTE) contains antioxidants that are present in green tea. The active constituents of green tea extract are catechins. This study demonstrates a spectrofluorimetric method for measuring GTE's catechin concentration based on its native fluorescence. To design a quick, sensitive, and ecological spectrofluorimetric approach, all features were investigated and adjusted. This method relies on determining the GTE ethanolic solution's native fluorescence at 312 nm after excitation at 227 nm. The calibration graph displayed a linear regression for values between 0.05 and 1.0 µg mL-1. The detection and quantification limits of the proposed technique were 0.008 and 0.026 µg mL-1, respectively. Two pure catechins present in GTE, (-)-epicatechin and (-)-epigallocatechin gallate, were examined by the proposed method. The analytical estimation of GTE in the pharmaceutical tablet was achieved effectively using this approach. An adequate degree of agreement was found when the findings were compared to those obtained by the comparative technique. Therefore, the novel strategy may be used in the GTE quality control study with minimal risks to people or the environment. The quantum yields of catechins were estimated. The validated technique was accepted by the International Council of Harmonization criteria.


Assuntos
Camellia sinensis , Catequina , Humanos , Catequina/análise , Espectrometria de Fluorescência , Extratos Vegetais , Chá , Antioxidantes/análise
12.
Arch Gynecol Obstet ; 309(3): 1021-1026, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38183422

RESUMO

PURPOSE: A prospective investigation to assess the impact of 3 months of treatment with epigallocatechin gallate (EGCG), vitamin D and D-chiro-inositol (DCI) in the treatment of uterine fibroids (UF) with laparoscopic myomectomy as evidenced by surgical outcomes and effect on liver function. METHODS: Non-pregnant or lactating women aged between 30 and 40 years were scheduled for laparoscopic myomectomy to treat symptoms or looking to conceive. After enrollment, patients were assigned to either (1) intervention group, assuming a total of 300 mg EGCG, 50 µg vitamin D, and 50 mg DCI divided in 2 pills per day for 3 months, or (2) control group, including untreated women scheduled to undergo laparoscopic myomectomy after 3 months. RESULTS: 91 patients completed the study. The comparison of the surgical outcomes between the intervention (n = 44) and the control (n = 47) groups revealed that the treatment significantly reduces the duration of surgery (41.93 ± 7.56 min vs 56.32 ± 10.63 min, p < 0.001). Moreover, the treatment also reduced blood loss during surgery (149.09 ± 25.40 mL vs 168.41 ± 21.34 mL, p < 0.001), resulting in treated patients having higher Hb levels at discharge 11.27 ± 0.82 mL vs 10.56 ± 0.82 mL, p < 0.01). The surgery induced an increase in AST and in total bilirubin regardless of the assigned group, and the treatment induced no change in liver function. CONCLUSIONS: Our data suggest that EGCG plus vitamin D, and DCI could represent a safe option for women with UF scheduled for laparoscopic myomectomy, improving surgical outcomes without affecting liver functionality.


Assuntos
Catequina/análogos & derivados , Laparoscopia , Leiomioma , Miomectomia Uterina , Neoplasias Uterinas , Humanos , Feminino , Adulto , Neoplasias Uterinas/tratamento farmacológico , Neoplasias Uterinas/cirurgia , Projetos Piloto , Vitamina D , Estudos Prospectivos , Lactação , Leiomioma/tratamento farmacológico , Leiomioma/cirurgia , Resultado do Tratamento
13.
Drug Chem Toxicol ; : 1-13, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38529831

RESUMO

Doxorubicin (Dox), an effective anticancer agent, is known for its genotoxic effects on normal cells. Phenolic compounds, renowned for their antitumor, antioxidant, and antigenotoxic properties, have gained prominence in recent years. This study investigates the individual and combined protective effects of rosmarinic acid (RA) and epigallocatechin gallate (EGCG) against Dox-induced genotoxicity using various in vitro test systems. The synergistic/antagonistic interaction of these combinations on Dox's chemotherapeutic effect is explored in breast cancer cell lines. Both RA and EGCG significantly mitigate Dox-induced genotoxicity in comet, micronucleus, and Ames assays. While Dox exhibits higher selectivity against MCF-7 cells, EGCG and RA show greater selectivity against MDA-MB-231 cells. The coefficient of drug interaction reveals a synergistic effect when RA or EGCG is combined with Dox in breast cancer cells. In conclusion, both EGCG and RA effectively reduce Dox-induced genetic damage and enhance Dox's cell viability-reducing effect in breast cancer cells.


Rosmarinic acid (RA) showed protective effect against doxorubicin-induced genotoxicity.Epigallocatechin gallate (EGCG) demonstrated pro-oxidant properties at high concentrations.EGCG and RA selectively targeted MDA-MB-231 cells.Synergistic effect was observed when EGCG or RA was administered together with Dox on breast cancer cells.

14.
Molecules ; 29(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38893466

RESUMO

Epigallocatechin gallate (EGCG), the principal catechin in green tea, exhibits diverse therapeutic properties. However, its clinical efficacy is hindered by poor stability and low bioavailability. This study investigated solid particle-in-oil-in-water (S/O/W) emulsions stabilized by whey protein isolate (WPI) and sodium caseinate (NaCas) as carriers to enhance the bioavailability and intestinal absorption of EGCG. Molecular docking revealed binding interactions between EGCG and these macromolecules. The WPI- and NaCas-stabilized emulsions exhibited high encapsulation efficiencies (>80%) and significantly enhanced the bioaccessibility of EGCG by 64% compared to free EGCG after simulated gastrointestinal digestion. Notably, the NaCas emulsion facilitated higher intestinal permeability of EGCG across Caco-2 monolayers, attributed to the strong intermolecular interactions between caseins and EGCG. Furthermore, the emulsions protected Caco-2 cells against oxidative stress by suppressing intracellular reactive oxygen species generation. These findings demonstrate the potential of WPI- and NaCas-stabilized emulsions as effective delivery systems to improve the bioavailability, stability, and bioactivity of polyphenols like EGCG, enabling their applications in functional foods and nutraceuticals.


Assuntos
Disponibilidade Biológica , Caseínas , Catequina , Emulsões , Proteínas do Soro do Leite , Catequina/análogos & derivados , Catequina/química , Humanos , Proteínas do Soro do Leite/química , Caseínas/química , Células CACO-2 , Emulsões/química , Simulação de Acoplamento Molecular , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Portadores de Fármacos/química , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/farmacocinética , Absorção Intestinal/efeitos dos fármacos
15.
Molecules ; 29(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38543009

RESUMO

Epigallocatechin gallate (EGCG) is a catechin, which is a type of flavonoid found in high concentrations in green tea. EGCG has been studied extensively for its potential health benefits, particularly in cancer. EGCG has been found to exhibit anti-proliferative, anti-angiogenic, and pro-apoptotic effects in numerous cancer cell lines and animal models. EGCG has demonstrated the ability to interrupt various signaling pathways associated with cellular proliferation and division in different cancer types. EGCG anticancer activity is mediated by interfering with various cancer hallmarks. This article summarize and highlight the effects of EGCG on cancer hallmarks and focused on the impacts of EGCG on these cancer-related hallmarks. The studies discussed in this review enrich the understanding of EGCG's potential as a therapeutic tool against cancer, offering a substantial foundation for scientists and medical experts to advance scientific and clinical investigations regarding EGCG's possibility as a potential anticancer treatment.


Assuntos
Catequina , Catequina/análogos & derivados , Neoplasias , Animais , Catequina/farmacologia , Catequina/uso terapêutico , Neoplasias/tratamento farmacológico , Proliferação de Células , Transdução de Sinais , Chá
16.
J Neurochem ; 166(2): 294-317, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37165774

RESUMO

The accumulation of amyloidogenic protein aggregates in neurons is a pathogenic hallmark of a large number of neurodegenerative diseases including Alzheimer's disease (AD). Small molecules targeting such structures and promoting their degradation may have therapeutic potential for the treatment of AD. Here, we searched for natural chemical compounds that decrease the abundance of stable, proteotoxic ß-sheet-rich amyloid-ß (Aß) aggregates in cells. We found that the polyphenol (-)-epigallocatechin gallate (EGCG) functions as a potent chemical aggregate degrader in SH-EP cells. We further demonstrate that a novel, fluorescently labeled EGCG derivative (EGC-dihydroxybenzoate (DHB)-Rhodamine) also shows cellular activity. It directly targets intracellular Aß42 aggregates and competes with EGCG for Aß42 aggregate binding in vitro. Mechanistic investigations indicated a lysosomal accumulation of Aß42 aggregates in SH-EP cells and showed that lysosomal cathepsin activity is critical for efficient EGCG-mediated aggregate clearance. In fact, EGCG treatment leads to an increased abundance of active cathepsin B isoforms and increased enzymatic activity in our SH-EP cell model. Our findings suggest that intracellular Aß42 aggregates are cleared through the endo-lysosomal system. We show that EGCG directly targets intracellular Aß42 aggregates and facilitates their lysosomal degradation. Small molecules, which bind to protein aggregates and increase their lysosomal degradation could have therapeutic potential for the treatment of amyloid diseases.


Assuntos
Doença de Alzheimer , Catequina , Humanos , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/metabolismo , Catequina/farmacologia , Catequina/química , Lisossomos/metabolismo
17.
Mol Cancer ; 22(1): 95, 2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37316830

RESUMO

Clinical hyperthermic intraperitoneal chemotherapy (HIPEC) is regarded as a potential treatment that can prolong survival of patients with peritoneal metastases after cytoreductive surgery. However, treated tumor cells are prone to becoming heat resistant to HIPEC therapy through high expression of heat shock proteins (HSPs). Here, a carrier-free bifunctional nanoinhibitor was developed for HIPEC therapy in the management of peritoneal metastases. Self-assembly of the nanoinhibitor was formed by mixing Mn ion and epigallocatechin gallate (EGCG) in a controllable manner. Such nanoinhibitor directly inhibited HSP90 and impaired the HSP90 chaperone cycle by reduced intracellular ATP level. Additionally, heat and Mn ion synergistically induced oxidative stress and expression of caspase 1, which activated GSDMD by proteolysis and caused pyroptosis in tumor cells, triggering immunogenic inflammatory cell death and induced maturation of dendritic cells through the release of tumor antigens. This strategy to inhibit heat resistance in HIPEC presented an unprecedented paradigm for converting "cold" tumors into "hot" ones, thus significantly eradicating disseminated tumors located deep in the abdominal cavity and stimulating immune response in peritoneal metastases of a mouse model. Collectively, the nanoinhibitor effectively induced pyroptosis of colon tumor cells under heat conditions by inhibiting heat stress resistance and increasing oxidative stress, which may provide a new strategy for treatment of colorectal peritoneal metastases.


Assuntos
Quimioterapia Intraperitoneal Hipertérmica , Neoplasias Peritoneais , Animais , Camundongos , Neoplasias Peritoneais/tratamento farmacológico , Proteínas de Choque Térmico HSP90 , Proteólise , Colo
18.
Microb Pathog ; 176: 105999, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36702369

RESUMO

Francisella tularensis is a highly infectious intracellular bacterium causing tularemia disease and is regarded as a potential biological weapon. The development of a vaccine, effective treatment, or prophylactic substances targeted against tularemia is in the forefront of interest and could help to prevent or mitigate possible malevolent acts by bioterrorism utilizing F. tularensis. The viability of F. tularensis, and thus of a tularemia disease outbreak, might potentially be suppressed by simple commonly available natural substances. Epigallocatechin gallate (EGCG) is contained in green tea and its antimicrobial effect has been described. Here, we show that EGCG can suppress F. tularensis growth and is able to reduce the bacterium's ability to replicate inside mouse bone marrow-derived macrophages (BMMs) without side effects on BMMs' own viability. We suggest one (but not the only) mechanism of EGCG action. We demonstrate that EGCG can block the main functions of HU protein, the important regulator of F. tularensis virulence, leading to overall attenuation of F. tularensis viability. EGCG can delay death of mice infected by F. tularensis and can be used as a prophylactic agent against tularemia disease. Postponing death by up to 2 days can provide sufficient opportunity to administer another treatment agent.


Assuntos
Catequina , Francisella tularensis , Tularemia , Animais , Camundongos , Tularemia/microbiologia , Proteínas de Ligação a DNA/metabolismo , Catequina/uso terapêutico
19.
Pharmacol Res ; 187: 106596, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36473629

RESUMO

Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of premature death worldwide. Inflammation and its biomarkers, like C-reactive protein (CRP), among the risk factors, such as hypertension, lipid disorders, and diabetes, may be also responsible for the residual cardiovascular disease (CVD) risk. Modern lipid-lowering treatment with statins, ezetimibe, PCSK9 inhibitors, or bempedoic acid does not fully protect against inflammation. The recommendations of the International Lipid Expert Panel (ILEP) indicate selected nutraceuticals with anti-inflammatory properties. Diet may have a significant impact on inflammation. Especially interesting in the context of inflammation is the consumption of coffee and tea. These drinks in many observational studies significantly reduced cardiovascular risk and mortality. The question is whether the anti-inflammatory effects of these drinks contribute significantly to the observed clinical effects. Thus, in this narrative review, we primarily discuss the anti-inflammatory properties of consuming tea and coffee. Based on a comprehensive analysis of the studies and their meta-analyses, inconsistent results were obtained, which makes it impossible to conclusively state how clinically significant the potential anti-inflammatory properties of black and green tea and coffee are. A number of confounding factors can cause the inconsistency of the available results. Consumption of tea and coffee appears to increase adiponectin concentrations, decrease reactive oxygen species, decrease low density lipoprotein (LDL) cholesterol concentrations (effect of green tea, etc.). Despite the still uncertain anti-inflammatory effect of tea and coffee, we recommend their consumption as a part of the healthy diet.


Assuntos
Doenças Cardiovasculares , Café , Humanos , Pró-Proteína Convertase 9 , Doenças Cardiovasculares/prevenção & controle , Chá , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Inflamação/tratamento farmacológico , Lipídeos
20.
Pharmacol Res ; 194: 106846, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37414199

RESUMO

Malignant proliferation and metastasis are the main causes of breast cancer death. The transcription factor high mobility group (HMG) box-containing protein 1 (HBP1) is an important tumor suppressor whose deletion or mutation is closely related to the appearance of tumors. Here, we investigated the role of HBP1 in breast cancer suppression. HBP1 enhances the activity of the tissue inhibitors of metalloproteinases 3 (TIMP3) promoter, thereby increasing protein and mRNA levels of TIMP3. TIMP3 increases the phosphatase and tensin homolog (PTEN) protein level by inhibiting its degradation and acts as a metalloproteinase inhibitor to inhibit the protein levels of MMP2/9. In this study, we demonstrated that the HBP1/TIMP3 axis plays a crucial role in inhibiting the tumorigenesis of breast cancer. HBP1 deletion interferes with the regulation of the axis and induces the occurrence and malignant progression of breast cancer. In addition, the HBP1/TIMP3 axis promotes the sensitivity of breast cancer to radiation therapy and hormone therapy. Our study opens new perspectives on the treatment and prognosis of breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , RNA Mensageiro/genética , Prognóstico , Regiões Promotoras Genéticas , Proteínas de Grupo de Alta Mobilidade/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Inibidor Tecidual de Metaloproteinase-3/genética , Inibidor Tecidual de Metaloproteinase-3/metabolismo
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