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1.
Braz. j. biol ; 83: e248746, 2023. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339351

RESUMO

Abstract Colorectal cancer (CRC) is one of the most common cancers leading to comorbidities and mortalities globally. The rational of current study was to evaluate the combined epigallocatechin gallate and quercetin as a potent antitumor agent as commentary agent for therapeutic protocol. The present study investigated the effect of epigallocatechin Gallate (EGCG) (150mg) and quercetin (200mg) at different proportions on proliferation and induction of apoptosis in human colon cancer cells (HCT-116). Cell growth, colonogenic, Annexin V in addition cell cycle were detected in response to phytomolecules. Data obtained showed that, the colony formation was inhibited significantly in CRC starting from the lowest concentration tested of 10 µg/mL resulting in no colonies as visualized by a phase-contrast microscope. Data showed a significant elevation in the annexin V at 100 µg/mL EGCG(25.85%) and 150 µg/mL quercetin (48.35%). Moreover, cell cycle analysis showed that this combination caused cell cycle arrest at the G1 phase at concentration of 100 µg/mL (72.7%) and 150 µg/mL (75.25%). The combined effect of epigallocatechin Gallate and quercetin exert antiproliferative activity against CRC, it is promising in alternative conventional chemotherapeutic agent.


Resumo O câncer colorretal (CCR) é um dos cânceres mais comuns, levando a comorbidades e mortalidade em todo o mundo. O racional do presente estudo foi avaliar a combinação de galato de epigalocatequina e quercetina como um agente antitumoral potente como agente de comentário para protocolo terapêutico. O presente estudo investigou o efeito de galato de epigalocatequina (EGCG) (150 mg) e quercetina (200 mg) em diferentes proporções na proliferação e indução de apoptose em células de câncer de cólon humano (HCT-116). O crescimento celular, colonogênico, anexina V, além do ciclo celular foram detectados em resposta a fitomoléculas. Os dados obtidos mostraram que a formação de colônias foi inibida significativamente no CRC a partir da concentração mais baixa testada de 10 µg/mL, resultando em nenhuma colônia conforme visualizado por um microscópio de contraste de fase. Os dados mostraram uma elevação significativa na anexina V a 100 µg/mL de EGCG (25,85%) e 150 µg/mL de quercetina (48,35%). Além disso, a análise do ciclo celular mostrou que essa combinação causou parada do ciclo celular na fase G1 na concentração de 100 µg/mL (72,7%) e 150 µg/mL (75,25%). O efeito combinado da epigalocatequina galato e quercetina exerce atividade antiproliferativa contra o CCR, é promissor como agente quimioterápico alternativo convencional.


Assuntos
Humanos , Neoplasias Colorretais/tratamento farmacológico , Catequina/análogos & derivados , Catequina/farmacologia , Quercetina/farmacologia , Ciclo Celular , Anexina A5 , Linhagem Celular Tumoral , Proliferação de Células
2.
Gen Physiol Biophys ; 41(4): 299-308, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35938963

RESUMO

This study evaluated the anti-inflammatory effect of epicatechin (EC) on acute lung injury (ALI) induced by lipopolysaccharide (LPS) of tracheal installation in BALB/c mice. It was observed that EC could alleviate not only the histopathological changes but also decrease the wet/dry weight (W/D) ratio of lung tissues. It also suppressed the release of IL-1ß, IL-6, and TNF-α in serum, bronchoalveolar lavage fluid (BALF), and lung tissues, respectively. A quantitative realtime PCR-based study further indicated that EC also inhibited the levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) mRNA in lung tissues. In addition, the Western blot report suggested that EC was closely involved in the inhibition of phosphorylation of ERK, JNK, p38, p65, and IκB in mitogen-activated protein kinases (MAPK) and nuclear factor-κB (NF-κB) signaling pathway. These results provide an experimental and theoretical basis for treating pulmonary inflammation by EC.


Assuntos
Lesão Pulmonar Aguda , Catequina , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Animais , Catequina/efeitos adversos , Citocinas , Lipopolissacarídeos/efeitos adversos , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais
3.
Food Res Int ; 159: 111639, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35940769

RESUMO

Predictable tea grading bears not only scientific merit, but also commercial value. Lu'an guapian green tea (LGGT) is one of the most famous green teas in China. Based on morphology and sensory flavour, LGGT was traditionally graded as first premium (FP), second premium (SP), first grade (FG), second grade (SG), third grade (TG) and summer grade (SuG). The chemical profiles and distinct metabolites distinguishing different grades of LGGT are yet to be defined, neither the grade related health benefits be evaluated. In present study, non-targeted metabolomics combined with chemometrics analysis showed that FP and SP, FG and SG exhibited high similarity, respectively. TG and SuG both exhibited great difference from the other grades. Therefore, LGGT could be regrouped into four grades. Furthermore, eight metabolites were identified and displayed grade related bio-markers of LGGT, which are gallic acid, catechin, gallocatechin, salicylic acid, theasinensin B, theasinensin C, kaempferol 3-(6''-rhanmnosylsoporoside) and l-linalool 3-[xylosyl-(1->6)-glucoside]. Quantitative analysis further confirmed that gallic acid, catechin, gallocatechin and salicylic acid were distinct grade-related metabolites. In vitro and in vivo data showed that methanol-extracts of higher grades LGGT exhibited more potent α-amylase and α-glucosidase inhibitory activity and hypoglyceamia effect than that of lower grades.


Assuntos
Catequina , Hipoglicemia , Catequina/análise , Ácido Gálico/análise , Humanos , Hipoglicemiantes/análise , Ácido Salicílico , Chá
4.
Biomed Res Int ; 2022: 9709365, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35915797

RESUMO

Background: Parkia clappertoniana Keay (Family: Fabaceae) (P. clappertoniana) fruit husk is commonly used in northern Ghana for wound treatment. However, this folk claim remains to be confirmed scientifically. Objective: This study investigated wound healing and antimicrobial effects of P. clappertoniana fruit husk extract (PCFHE) by using excision wound model in rats. Materials and Methods: After preparation and phytochemical analysis of PCFHE, it was reconstituted in purified water and emulsifying ointment yielding a wound healing formula (0.3, 1, and 3%). Excision wounds were established in healthy male Sprague-Dawley rats (aged 8-10 weeks; weighing 150-200 g). Rats were randomly assigned into six groups (model, 1% silver sulfadiazine [SSD], vehicle, and PCFHE [0.3, 1, and 3%, respectively]) and topically treated daily until complete wound healing. The endpoints (period of epithelialization, wound contraction, collagen content, erythema index, oedema index, inflammatory cell infiltration, and antimicrobial activity) were assessed for all groups. Minimum fungicidal concentration (MFC), minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and time-kill were assessed. Results: Quercetin and catechin were detected in PCFHE. Compared to model and vehicle groups, PCFHE-treatment groups improved wound healing and antimicrobial (MBC, MFC, and MIC) endpoints. PCFHE demonstrated bacteriostatic and fungicidal effects against identified wound contaminants (Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, and Candida albicans). Conclusion: P. clappertoniana fruit husk possesses wound healing and antimicrobial effects in excisional wounds in rats that confirms its folk use, and the reported pharmacological properties of PCFHE are attributable to its quercetin and catechin phyto-constituents.


Assuntos
Anti-Infecciosos , Fabaceae , Extratos Vegetais , Cicatrização , Animais , Anti-Infecciosos/farmacologia , Catequina/farmacologia , Fabaceae/química , Frutas , Masculino , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Quercetina/farmacologia , Ratos , Ratos Sprague-Dawley , Cicatrização/efeitos dos fármacos
5.
Contrast Media Mol Imaging ; 2022: 8639139, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35919501

RESUMO

Objective: To explore the effect and mechanism of epigallocatechin gallate (EGCG) in mice with coronary heart disease (CHD). Methods: Firstly, a CHD model of mouse was established by feeding mice high-fat diet and randomly divided into four groups, including Model group (0.5% sodium cholate) and 10 mg/kg EGCG, 20 mg/kg EGCG, and 40 mg/kg EGCG groups. After oral administration of sodium cholate or EGCG, HE staining was conducted to assess the pathological changes of mouse cardiac tissues in each group of mice, biochemical kits to measure the levels of blood lipid and oxidative stress substance activity, and western blot to detect matrix metalloproteinase 2 (MMP-2), vascular endothelial growth factor (VEGFA), as well as expression levels of protein related to Nrf2/HO-1/NQO1 pathway in cardiac tissues. Results: The mice in the CHD model appeared to have myocardial pathological damage with elevated serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and decreased high-density lipoprotein cholesterol (HDL-C). Of note, administration of EGCG significantly attenuated myocardial injuries and improved blood lipid levels in mice in a concentration-dependent manner. The advent of EGCG significantly decreased the expression of VEGFA and MMP-2 and increased the activity of superoxide dismutase (SOD), when reducing the content of reactive oxygen species (ROS) in the myocardial tissue and upregulating the expression of HO-1, NQO1, and Nrf2. Conclusion: EGCG may reduce atherosclerotic plaque and alleviate pathological damage in the cardiac tissue of CHD mice as well as improve blood lipid levels with antioxidative effect. The mechanism of its effect may be related to the activation of the Nrf2/HO-1/NQO1 antioxidant pathway in vivo of the CHD mice.


Assuntos
Doença das Coronárias , Fator 2 Relacionado a NF-E2 , Animais , Antioxidantes/farmacologia , Catequina/análogos & derivados , Colesterol , Doença das Coronárias/tratamento farmacológico , Lipídeos , Metaloproteinase 2 da Matriz , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Colato de Sódio , Fator A de Crescimento do Endotélio Vascular
6.
Int J Med Sci ; 19(7): 1131-1137, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35919819

RESUMO

Although melanogenesis is a defense mechanism against ultraviolet (UV)-induced skin damage, abnormally excessive melanin production causes pigmentation disorders. Tyrosinase, as a key factor for melanin synthesis, plays an important role in inducing skin pigmentation. Therefore, the inhibition of tyrosinase is crucial in preventing skin pigmentation in the cosmetics and medicine fields. However, the majority of well-known tyrosinase inhibitors have been discontinued due to toxic effects on the skin or lack of selectivity and/or stability. In this study, we evaluated possible anti-melanogenic effects of catechin-7-O-α-L-rhamnopyranoside (C7R) isolated from the stem bark of Ulmus parvifolia, to discover a new tyrosinase inhibitor that has both safety and stability. When C7R was pretreated in B16F10 melanoma cells stimulated by α-melanocyte-stimulating hormone, this compound reduced melanin accumulation and murine tyrosinase activity. In line with these results, C7R inhibits tyrosinase purified from a mushroom in vitro like kojic acid and arbutin. Furthermore, C7R exhibited a competitive inhibition on a Lineweaver-Burk plot. Next, the underlying mechanisms of the C7R-mediated tyrosinase inhibitory effect were sought through docking simulation and pharmacophore analysis between tyrosinase residues and C7R. The results of these analyses showed that C7R had binding energy of -14.5kcal/mol, and indicated that C7R interacts with tyrosinase through an aromatic ring and various hydrophobic and hydrogen bonds. Together, our results suggest that C7R can be applied as a novel natural anti-melanogenic agent that inhibits tyrosinase.


Assuntos
Catequina , Melanoma Experimental , Animais , Catequina/farmacologia , Catequina/uso terapêutico , Linhagem Celular Tumoral , Melaninas , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/metabolismo , Camundongos , Monofenol Mono-Oxigenase/metabolismo , alfa-MSH/farmacologia
7.
Biochim Biophys Acta Biomembr ; 1864(10): 183999, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35820494

RESUMO

(-)-Epigallocatechin-3-gallate (EGCG) is a flavonoid known for its good antioxidant potential and health benefits. It is one of the most intriguing flavonoids, especially because of its specific interactions with model lipid membranes. It was noticed that EGCG might form EGCG rich domains/rafts at certain compositions of lipid membranes. In this article, we investigate whether EGCG forms EGCG rich domains when incorporated in 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) liposomes. Our results show that EGCG decreases lipid ordering parameter in ordered membranes and increases it in the case of disordered ones. Also, incorporation of EGCG does not affect the zeta-potential and shape of the liposomes, but it can induce aggregation of liposomes. Our study also demonstrates that liposomes with incorporated EGCG are highly protected against UV-light induced oxidation.


Assuntos
Catequina , Lipossomos , Antioxidantes , Catequina/análogos & derivados , Lipídeos
8.
Food Chem Toxicol ; 167: 113306, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35863485

RESUMO

Although epigallocatechin-3-gallate (EGCG), the major polyphenol in green tea, has been shown to have many benefits, the effect of EGCG exposure in utero on adult uterine development is unclear. In this study, pregnant C57BL/6 mice were exposed to 1 mg/kg body weight (bw) EGCG dissolved in drinking water from gestational days 0.5-16.5. A significant decrease in uterine weight was observed in the adult female mice, accompanied by uterine atrophy, inflammation, and fibrosis in the endometrium. Uterine atrophy was attributed to the thinning of the endometrial stromal layer and a significant reduction in endometrial cell proliferation. The expression levels of related proteins in the NF-κB and RAF/MEK/ERK signaling pathways were significantly increased, which might be responsible for the occurrence of inflammation. Activation of the transforming growth factor beta (TGF-ß1)/Smad signaling pathway might be involved in the development of endometrial fibrosis. The changes in the expression of estrogen receptor α, ß (ERα, ERß), progesterone receptor (PGR), and androgen receptor (AR) might lead to changes in the aforementioned signaling pathways. The promoter region methylation level of Esr2 was increased, and the expression of DNMT3A was evaluated. Our study indicates a risk of EGCG intake during pregnancy affecting uterine development in offspring.


Assuntos
Catequina , Animais , Atrofia , Catequina/análogos & derivados , Catequina/farmacologia , Feminino , Fibrose , Inflamação , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Chá
9.
Nutrients ; 14(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35889906

RESUMO

Being in a prolonged depressed state increases the risk of developing depression. To investigate whether green tea intake is effective in improving depression-like moods, we used an experimental animal model of depression with lipopolysaccharide (LPS) and clarified the effects of green tea on the biological stress response and inflammation in the brain. Regarding the stress reduction effect of green tea, we found that the sum of caffeine (C) and epigallocatechin gallate (E) relative to the sum of theanine (T) and arginine (A), the major components of green tea, or the CE/TA ratio, is important. The results showed that depression-like behavior, adrenal hypertrophy as a typical stress response, and brain inflammation were suppressed in mice fed green tea components with CE/TA ratios of 2 to 8. In addition, the expression of Npas4, which is reduced in anxiety and depression, was maintained at the same level as controls in mice that consumed green tea with a CE/TA ratio of 4. In clinical human trials, the consumption of green tea with CE/TA ratios of 3.9 and 4.7 reduced susceptibility to subjective depression. These results suggest that the daily consumption of green tea with a CE/TA ratio of 4-5 is beneficial to improving depressed mood.


Assuntos
Catequina , Chá , Animais , Arginina/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Encéfalo , Cafeína/análise , Cafeína/farmacologia , Catequina/farmacologia , Humanos , Hipertrofia , Camundongos
10.
J Parasitol ; 108(4): 301-305, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35877154

RESUMO

New antibabesial drugs are required to fight resistant parasites, and plant-derived natural products are a robust source. Six kinds of natural product extracts derived from herbal medicines that are traditionally used for the treatment of malaria were selected to test the antibabesial effect on Babesia gibsoni in vitro and in vivo. Parasitized blood was collected from dogs infected with B. gibsoni to evaluate the inhibitory effect of verbenalin, catechin hydrate, dihydrolycorine, embelin, ursolic acid, agrimol B, and bruceine H in vitro. The expression levels of the 18S rRNA gene in all drug-treated groups were determined by relative quantification using a real-time PCR method. Significant inhibition of the in vitro growth of B. gibsoni was observed after treatment by those natural product extracts (200 nM concentration) (P < 0.05). Catechin hydrate showed the highest activity in vitro due to the lowest expression levels of the 18S rRNA gene. The IC50 value of catechin hydrate against B. gibsoni was 273 nM. In B. gibsoni infected dogs, intravenous administrations of catechin hydrate and diminazene aceturate showed significant (P < 0.05) inhibition of B. gibsoni growth at a dose of 11 mg/kg and 10 mg/kg, respectively, compared to the control group. The results of our study may suggest that catechin hydrate may be a promising alternative to treat canine babesiosis caused by B. gibsoni.


Assuntos
Babesia , Babesiose , Produtos Biológicos , Catequina , Doenças do Cão , Animais , Babesia/genética , Babesiose/tratamento farmacológico , Babesiose/parasitologia , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Catequina/farmacologia , Catequina/uso terapêutico , Doenças do Cão/tratamento farmacológico , Doenças do Cão/parasitologia , Cães , RNA Ribossômico 18S/genética
11.
Int J Mol Sci ; 23(14)2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35886943

RESUMO

In recent years, many natural foods and herbs rich in phytochemicals have been proposed as health supplements for patients with metabolic syndrome (MetS). Theaflavins (TFs) are a polyphenol hydroxyl substance with the structure of diphenol ketone, and they have the potential to prevent and treat a wide range of MetS. However, the stability and bioavailability of TFs are poor. TFs have the marvelous ability to alleviate MetS through antiobesity and lipid-lowering (AMPK-FoxO3A-MnSOD, PPAR, AMPK, PI3K/Akt), hypoglycemic (IRS-1/Akt/GLUT4, Ca2+/CaMKK2-AMPK, SGLT1), and uric-acid-lowering (XO, GLUT9, OAT) effects, and the modulation of the gut microbiota (increasing beneficial gut microbiota such as Akkermansia and Prevotella). This paper summarizes and updates the bioavailability of TFs, and the available signaling pathways and molecular evidence on the functionalities of TFs against metabolic abnormalities in vitro and in vivo, representing a promising opportunity to prevent MetS in the future with the utilization of TFs.


Assuntos
Microbioma Gastrointestinal , Síndrome Metabólica , Proteínas Quinases Ativadas por AMP , Biflavonoides , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina , Catequina , Humanos , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/metabolismo , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt
12.
Int J Mol Sci ; 23(14)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35887117

RESUMO

The objective of this study was to investigate the protective effects and potential molecular mechanisms of procyanidin B2 (PB2) in MAC-T (mammary alveolar cells-large T antigen) cells during heat stress (HS). The MAC-T cells were divided into three treatment groups: control (37 °C), HS (42 °C), and PB2 + HS (42 °C). Compared with MAC-T cells that were consistently cultured at 37 °C, acute HS treatment remarkably decreased cell viability, reduced activities of catalase (CAT), superoxide dismutase (SOD), and total antioxidant capacity (T-AOC), and elevated intracellular levels of malondialdehyde (MDA) and reactive oxygen species (ROS). Additionally, nuclear factor erythroid 2-related factor 2 (Nrf2) was activated and translocated to the nucleus, in accompaniment with upregulation of Nrf2, heme oxygenase 1 (HO-1), thioredoxin reductase 1 (Txnrd1), and heat shock protein 70 (HSP70). In parallel, both mRNA transcript and actual protein secretion of pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß), were increased by heat stress. Pretreatment of MAC-T cells with 0~25 µM PB2 alleviated the decline of cell viability by HS in a dose-dependent fashion and protected cells against HS-induced oxidative stress, as evidenced by significantly improved CAT, SOD, and T-AOC activity, as well as with decreased MDA and ROS generation. Furthermore, PB2 further activated the Nrf2 signaling pathway and reversed the inflammatory response induced by HS. Silencing of Nrf2 by si-Nrf2 transfection not only exacerbated HS-induced cell death and provoked oxidative stress and the inflammatory response, but also greatly abolished the cytoprotective effects under HS of PB2. In summary, PB2 protected MAC-T cells against HS-induced cell death, oxidative stress, and inflammatory response, partially by operating at the Nrf2 signal pathway.


Assuntos
Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Biflavonoides , Catequina , Bovinos , Células Epiteliais/metabolismo , Heme Oxigenase-1/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proantocianidinas , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
13.
Food Res Int ; 158: 111534, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35840230

RESUMO

The objective of this paper was to investigate the interactions between (-)-Epigallocatechin-3-gallate (EGCG) and whey protein isolate (WPI) by covalent and non-covalent combinations and the effects of the interactions on the conformational and functional changes of whey protein. Conformational changes in the secondary structure of whey protein with various concentrations of EGCG were studied using FTIR spectra. EGCG was more likely to form covalent bonds than non-covalent bonds when it interacted with whey proteins. The addition of EGCG altered the conformation of whey protein. The content of ß-sheet decreased, while that of ß-turn increased, however, the random coil remained unchanged. An reduction in surface hydrophobicity was observed in all the WPI-EGCG complexes, suggesting that modification in secondary structure of WPI were induced by EGCG. Additionally, the emulsifying and foaming attributes of WPI were enhanced after interaction with EGCG. This study confirms that EGCG can enhance the functional properties of WPI. It is also a pointer to the possible application of WPI-EGCG complexes in the dairy industry.


Assuntos
Catequina , Catequina/análogos & derivados , Catequina/química , Emulsões/química , Interações Hidrofóbicas e Hidrofílicas , Proteínas do Soro do Leite/química
14.
Food Res Int ; 158: 111542, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35840238

RESUMO

Green tea cream, the precipitate formed in cooled green tea infusion, appears a negative effect on flavor. To explain the mechanism of green tea cream, complexations between four catechins (CATs) and caffeine (CAF) were engineered and characterized. Dynamic light scattering, high performance liquid chromatography, scanning electron microscopy, fourier-transform infrared spectroscopy, UV-visible absorption spectrum, and x-ray diffraction were used to reveal the differences between ester catechins and non-ester catechins in the dynamic complexation process, particle shape, and precipitate mechanism with caffeine. The results indicated that CATs and CAF affected each other's microenvironment in aqueous solution and Guanidine hydrochloride (GH) weakened the effect both in solution and precipitate. In addition, the 1:1 complex structure of EGC-CAF was first proved, the hydrogen bond, CH…π and π…π interaction were the forces of CAT-CAF complexes by XRD. These results provided a new perspective to the mechanism analysis of green tea cream.


Assuntos
Catequina , Chá , Cafeína/análise , Catequina/análise , Cromatografia Líquida de Alta Pressão , Difusão Dinâmica da Luz , Chá/química
15.
Oxid Med Cell Longev ; 2022: 3047425, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35847580

RESUMO

Background: Osteoarthritis (OA) is a common degenerative joint disease that may be closely linked to inflammation and oxidative stress destroying the balance of cartilage matrix. Theaflavin-3,3'-digallate (TFDG), a natural substance derived from black tea, has been reported to restrict the activity of inflammatory cytokines and effectively eliminate reactive oxygen species (ROS) in various diseases. However, it is not clear whether TFDG can improve OA. Methods: Chondrocytes were treated with or without IL-1ß and 20 µM and 40 µM TFDG. The effect of TFDG on the proliferation of chondrocytes was detected by CCK8. RT-qPCR was used to detect the gene expression of inflammatory factors, extracellular matrix synthesis, and degradation genes. Western blot and immunofluorescence assays were used to detect the protein expression. The fluorescence intensity of reactive oxygen species labeled by DCFH-DA was detected by flow cytometry. We established an OA rat model by performing destabilized medial meniscus (DMM) surgery to observe whether TFDG can protect chondrocytes under arthritis in vivo. Results: TFDG was found to inhibit proinflammatory factors (IL-6, TNF-α, iNOS, and PGE) and matrix-degrading enzymes (MMP13, MMP3, and ADAMTS5) expression and protected extracellular matrix components of chondrocytes (ACAN, COL2, and SOX9). TFDG accelerated the scavenging of ROS caused by IL-1ß according to the Nrf2 signaling pathway activation. At the same time, TFDG suppressed the PI3K/AKT/NF-κB and MAPK signaling pathways to delay the inflammatory process. The cartilage of DMM rats receiving TFDG showed lower Osteoarthritis Research Society International (OARSI) scores and expressed higher levels of COL2 and Nrf2 compared with those of rats in the DMM group. Conclusion: TFDG could protect cartilage from degradation and alleviate osteoarthritis in rats, which suggests that TFDG has potential as a drug candidate for OA therapy.


Assuntos
Fator 2 Relacionado a NF-E2 , Osteoartrite , Animais , Antioxidantes/metabolismo , Biflavonoides , Cartilagem/metabolismo , Catequina/análogos & derivados , Condrócitos/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo
16.
J Agric Food Chem ; 70(27): 8264-8273, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35786898

RESUMO

Epigallocatechin-3-gallate (EGCG), a major green tea polyphenol, has beneficial effects on human health. This study aimed to elucidate the detailed EGCG sulfation process to better understand its phase II metabolism, a process required to maximize its health benefits. Results show that kinetic activity of sulfation in the human liver and intestinal cytosol is 2-fold and 60- to 300-fold higher than that of methylation and glucuronidation, respectively, suggesting sulfation as the key metabolic pathway. Moreover, SULT1A1 and SULT1A3 are responsible for sulfation in the liver and intestine, respectively. Additionally, our human ingestion study revealed that the concentration of EGCG-4″-sulfate in human plasma (Cmax: 177.9 nmol·L-1, AUC: 715.2 nmol·h·L-1) is equivalent to free EGCG (Cmax: 233.5 nmol·L-1, AUC: 664.1 nmol·h·L-1), suggesting that EGCG-4″-sulfate is the key metabolite. These findings indicate that sulfation is a crucial factor for improving EGCG bioavailability, while also advancing the understanding of the bioactivity and toxicity of EGCG.


Assuntos
Catequina , Catequina/análogos & derivados , Humanos , Redes e Vias Metabólicas , Sulfatos , Chá
17.
Cell Death Dis ; 13(7): 594, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35821123

RESUMO

Apoptosis is a critical event in the pathogenesis of lung ischemia/reperfusion (I/R) injury. Sirtuin 3 (SIRT3), an important deacetylase predominantly localized in mitochondria, regulates diverse physiological processes, including apoptosis. However, the detailed mechanisms by which SIRT3 regulates lung I/R injury remain unclear. Many polyphenols strongly regulate the sirtuin family. In this study, we found that a polyphenol compound, procyanidin B2 (PCB2), activated SIRT3 in mouse lungs. Due to this effect, PCB2 administration attenuated histological lesions, relieved pulmonary dysfunction, and improved the survival rate of the murine model of lung I/R injury. Additionally, this treatment inhibited hypoxia/reoxygenation (H/R)-induced A549 cell apoptosis and rescued Bcl-2 expression. Using Sirt3-knockout mice and specific SIRT3 knockdown in vitro, we further found that SIRT3 strongly protects against lung I/R injury. Sirt3 deficiency or enzymatic inactivation substantially aggravated lung I/R-induced pulmonary lesions, promoted apoptosis, and abolished PCB2-mediated protection. Mitochondrial pyruvate kinase M2 (PKM2) inhibits apoptosis by stabilizing Bcl-2. Here, we found that PKM2 accumulates and is hyperacetylated in mitochondria upon lung I/R injury. By screening the potential sites of PKM2 acetylation, we found that SIRT3 deacetylates the K433 residue of PKM2 in A549 cells. Transfection with a deacetylated mimic plasmid of PKM2 noticeably reduced apoptosis, while acetylated mimic transfection abolished the protective effect of PKM2. Furthermore, PKM2 knockdown or inhibition in vivo significantly abrogated the antiapoptotic effects of SIRT3 upregulation. Collectively, this study provides the first evidence that the SIRT3/PKM2 pathway is a protective target for the suppression of apoptosis in lung I/R injury. Moreover, this study identifies K433 deacetylation of PKM2 as a novel modification that regulates its anti-apoptotic activity. In addition, PCB2-mediated modulation of the SIRT3/PKM2 pathway may significantly protect against lung I/R injury, suggesting a novel prophylactic strategy for lung I/R injury.


Assuntos
Biflavonoides , Catequina , Isquemia , Leucemia Mieloide Aguda , Pulmão , Proantocianidinas , Traumatismo por Reperfusão , Sirtuína 3 , Animais , Biflavonoides/farmacologia , Catequina/farmacologia , Isquemia/metabolismo , Leucemia Mieloide Aguda/metabolismo , Pulmão/irrigação sanguínea , Pulmão/metabolismo , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proantocianidinas/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Piruvato Quinase/genética , Piruvato Quinase/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Sirtuína 3/genética , Sirtuína 3/metabolismo , Regulação para Cima/efeitos dos fármacos
18.
Nanotechnology ; 33(41)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35777311

RESUMO

Bacterial infections pose a serious threat to human health, and the development of new antibiotics has not kept pace with the development of bacterial resistance. Therefore, there is an urgent need to design antibiotic-like nano-formulations that break through bacterial resistance mechanisms. In this work, we successfully synthesized a safe and effective antibacterial nano-formulation of Se@Ag@EGCG by self-assembly of epigallocatechin gallate (EGCG)-coated silver nanoparticles (Ag) on the surface of selenium nanowires (Se). Thein vitrobacteriostatic results showed that 40µg ml-1Se@Ag@EGCG had significant antibacterial activity against drug-resistantStaphylococcus aureus(S. aureus) andEscherichia coli(E. coli) by destroying the formation of bacterial biofilm, promoting the production of high concentration reactive oxygen species and destroying bacterial cell wall. In addition, the results ofin vivoantibacterial experiments showed that subcutaneous administration of 10 mg kg-1of Se@Ag@EGCG could promote wound healing by reducing apoptosis and inflammatory responses in infected wounds. It is worth mentioning that the reduced and modified Se@Ag@EGCG by this natural product has negligiblein vivotoxicity. This development strategy of nano-antibacterial materials, which breaks through the drug resistance mechanism, provides new ideas for the development of drugs for drug-resistant bacterial infections.


Assuntos
Infecções Bacterianas , Nanopartículas Metálicas , Nanofios , Selênio , Antibacterianos/farmacologia , Biofilmes , Catequina/análogos & derivados , Escherichia coli , Humanos , Espécies Reativas de Oxigênio , Selênio/farmacologia , Prata/farmacologia , Staphylococcus aureus
19.
Food Funct ; 13(14): 7572-7581, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35815842

RESUMO

Many clinical studies have demonstrated the beneficial effects of black tea on cardiovascular diseases. However, the antiplatelet and antithrombotic activities of theaflavin (TF-1) remain unknown. In this study, we aimed to investigate the beneficial effects of TF-1 on platelet activation and thrombosis formation both in vitro and in vivo. Firstly, the in vitro antiplatelet activity of TF-1 was analyzed using platelets isolated from human blood via aggregometry, flow cytometry, the ELISA kit, western blot and fluorescence microscopy. Subsequently, the in vivo analysis of the hemostatic state and thrombosis formation was carried out in C57BL/6 mice based on the tail bleeding time and an FeCl3-induced arterial thrombus model. The results showed that TF-1 could prominently inhibit platelet aggregation in a dose-dependent manner, and attenuate P-selectin expression, fibrinogen binding, spreading and thromboxane A2 (TxA2) formation. Western blot analysis showed that TF-1 potently inhibited spleen tyrosine kinase (Syk) and Akt (ser473/474) phosphorylation. The in vivo data further confirmed the inhibition of platelet activation by TF-1 with a prolonged arterial occlusion time (from 15.0 ± 1.1 minutes to 40.0 ± 5.4 minutes). All the results indicated that TF-1 is a powerful inhibitor of platelet activation and thrombosis formation in C57BL/6 mice, and could be developed as a novel food-based inhibitor of thrombotic disorders.


Assuntos
Ativação Plaquetária , Trombose , Animais , Antioxidantes/farmacologia , Biflavonoides , Plaquetas , Catequina , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Agregação Plaquetária , Trombose/tratamento farmacológico
20.
AAPS PharmSciTech ; 23(6): 187, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35798907

RESUMO

Tea catechins are a group of flavonoids that show many bioactivities. Catechins have been extensively reported as a potential treatment for skin disorders, including skin cancers, acne, photoaging, cutaneous wounds, scars, alopecia, psoriasis, atopic dermatitis, and microbial infection. In particular, there has been an increasing interest in the discovery of cosmetic applications using catechins as the active ingredient because of their antioxidant and anti-aging activities. However, active molecules with limited lipophilicity have difficulty penetrating the skin barrier, resulting in low bioavailability. Nevertheless, topical application is a convenient method for delivering catechins into the skin. Nanomedicine offers an opportunity to improve the delivery efficiency of tea catechins and related compounds. The advantages of catechin-loaded nanocarriers for topical application include high catechin loading efficiency, sustained or prolonged release, increased catechin stability, improved bioavailability, and enhanced accumulation or targeting to the nidus. Further, various types of nanoparticles, including liposomes, niosomes, micelles, lipid-based nanoparticles, polymeric nanoparticles, liquid crystalline nanoparticles, and nanocrystals, have been employed for topical catechin delivery. These nanoparticles can improve catechin permeation via close skin contact, increased skin hydration, skin structure disorganization, and follicular uptake. In this review, we describe the catechin skin delivery approaches based on nanomedicine for treating skin disorders. We also provide an in-depth description of how nanoparticles effectively improve the skin absorption of tea catechins and related compounds, such as caffeine. Furthermore, we summarize the possible future applications and the limitations of nanocarriers for topical delivery at the end of this review article.


Assuntos
Catequina , Absorção Cutânea , Disponibilidade Biológica , Pele/metabolismo , Chá/química , Chá/metabolismo
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