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1.
Exp Eye Res ; 239: 109787, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38211683

RESUMO

Retinal ganglion cell (RGC) death and axonal loss cause irreversible vision loss upon optic nerve (ON) injury. We have independently demonstrated that mesenchymal stem cells (MSCs) and green tea extract (GTE) promote RGC survival and axonal regeneration in rats with ON injury. Here we aimed to evaluate the combined treatment effect of human bone marrow-derived MSCs (hBM-MSCs) and GTE on RGC survival and axonal regeneration after ON injury. Combined treatment of hBM-MSCs and GTE promoted RGC survival and neurite outgrowth/axonal regeneration in ex vivo retinal explant culture and in rats after ON injury. GTE increased Stat3 activation in the retina after combined treatment, and enhanced brain-derived neurotrophic factor secretion from hBM-MSCs. Treatment of 10 µg/mL GTE would not induce hBM-MSC apoptosis, but inhibited their proliferation, migration, and adipogenic and osteogenic differentiation in vitro with reducing matrix metalloproteinase secretions. In summary, this study revealed that GTE can enhance RGC protective effect of hBM-MSCs, suggesting that stem cell priming could be a prospective strategy enhancing the properties of stem cells for ON injury treatment.


Assuntos
Células-Tronco Mesenquimais , Traumatismos do Nervo Óptico , Ratos , Humanos , Animais , Traumatismos do Nervo Óptico/terapia , Traumatismos do Nervo Óptico/metabolismo , Células Ganglionares da Retina/metabolismo , Osteogênese , Chá/metabolismo , Regeneração Nervosa/fisiologia , Sobrevivência Celular/fisiologia , Axônios/metabolismo
2.
Br J Nutr ; 131(7): 1125-1157, 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38031409

RESUMO

Research indicates that green tea extract (GTE) supplementation is beneficial for a range of conditions, including several forms of cancer, CVD and liver diseases; nevertheless, the existing evidence addressing its effects on body composition, oxidative stress and obesity-related hormones is inconclusive. This systematic review and meta-analysis aimed to investigate the effects of GTE supplementation on body composition (body mass (BM), body fat percentage (BFP), fat mass (FM), BMI, waist circumference (WC)), obesity-related hormones (leptin, adiponectin and ghrelin) and oxidative stress (malondialdehyde (MDA) and total antioxidant capacity (TAC)) markers. We searched proper databases, including PubMed/Medline, Scopus and Web of Science, up to July 2022 to recognise published randomised controlled trials (RCT) that investigated the effects of GTE supplementation on the markers mentioned above. A random effects model was used to carry out a meta-analysis. The heterogeneity among the studies was assessed using the I2 index. Among the initial 11 286 studies identified from an electronic database search, fifty-nine studies involving 3802 participants were eligible to be included in this meta-analysis. Pooled effect sizes indicated that BM, BFP, BMI and MDA significantly reduced following GTE supplementation. In addition, GTE supplementation increased adiponectin and TAC, with no effects on FM, leptin and ghrelin. Certainty of evidence across outcomes ranged from low to high. Our results suggest that GTE supplementation can attenuate oxidative stress, BM, BMI and BFP, which are thought to negatively affect human health. Moreover, GTE as a nutraceutical dietary supplement can increase TAC and adiponectin.


Assuntos
Antioxidantes , Leptina , Humanos , Adiponectina/farmacologia , Antioxidantes/farmacologia , Composição Corporal , Índice de Massa Corporal , Suplementos Nutricionais , Grelina , Leptina/farmacologia , Obesidade , Estresse Oxidativo , Extratos Vegetais/farmacologia , Chá
3.
BMC Vet Res ; 20(1): 374, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39175036

RESUMO

BACKGROUND: Feline Herpesvirus type-1 (FHV-1) is a worldwide spread pathogen responsible for viral rhinotracheitis and conjunctivitis in cats that, in the most severe cases, can lead to death. Despite the availability of a variety of antiviral medications to treat this illness, mainly characterized by virostatic drugs that alter DNA replication, their use is often debated. Phytotherapeutic treatments are a little-explored field for FHV-1 infections and reactivations. In this scenario, natural compounds could provide several advantages, such as reduced side effects, less resistance and low toxicity. The purpose of this study was to explore the potential inhibitory effects of the green tea extract (GTE), consisting of 50% of polyphenols, on FHV-1 infection and reactive oxygen species (ROS) production. RESULTS: Crandell-Reese feline kidney (CRFK) cells were treated with different doses of GTE (10-400 µg/mL) during the viral adsorption and throughout the following 24 h. The MTT and TCID50 assays were performed to determine the cytotoxicity and the EC50 of the extract, determining the amounts of GTE used for the subsequent investigations. The western blot assay showed a drastic reduction in the expression of viral glycoproteins (i.e., gB and gI) after GTE treatment. GTE induced not only a suppression in viral proliferation but also in the phosphorylation of Akt protein, generally involved in viral entry. Moreover, the increase in cell proliferation observed in infected cells upon GTE addition was supported by enhanced expression of Bcl-2 and Bcl-xL anti-apoptotic proteins. Finally, GTE antioxidant activity was evaluated by dichloro-dihydro-fluorescein diacetate (DCFH-DA) and total antioxidant capacity (TAC) assays. The ROS burst observed during FHV-1 infection was mitigated after GTE treatment, leading to a reduction in the oxidative imbalance. CONCLUSIONS: Although further clinical trials are necessary, this study demonstrated that the GTE could potentially serve as natural inhibitor of FHV-1 proliferation, by reducing viral entry. Moreover, it is plausible that the extract could inhibit apoptosis by modulating the intrinsic pathway, thus affecting ROS production.


Assuntos
Antivirais , Infecções por Herpesviridae , Extratos Vegetais , Espécies Reativas de Oxigênio , Varicellovirus , Replicação Viral , Animais , Gatos , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Varicellovirus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Infecções por Herpesviridae/tratamento farmacológico , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/virologia , Antivirais/farmacologia , Linhagem Celular , Chá/química , Doenças do Gato/tratamento farmacológico , Doenças do Gato/virologia , Camellia sinensis/química
4.
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
5.
Arch Gynecol Obstet ; 309(4): 1509-1514, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37737883

RESUMO

PURPOSE: In the following work, we investigated the effect of matcha green tea extract (MTE) on MCF-7 breast cancer cell viability and estrogen receptor-beta expression (ERß). METHODS: MCF-7 cells were stimulated with MTE at concentrations of 5 and 10 µg/ml. Cell viability was assessed using a water-soluble tetrazolium assay (WST-1 assay) after an incubation time of 72 h. ERß was quantified at gene level by real-time polymerase chain reaction (PCR). A western blot (WB) was carried out for the qualitative assessment of the expression behavior of on a protein level. RESULTS: The WST-1 test showed a significant inhibition of viability in MFC-7 cells after 72 h at 10 µg/ml. The WB demonstrated a significant quantitative decrease of ERß at protein level with MTE concentrations of 10 µg/ml. In contrast, the PCR did not result in significant downregulation of ERß. CONCLUSION: MTE decreases the cell viability of MCF-7 cells and furthermore leads to a decrease of ERß at protein level.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Células MCF-7 , Receptor beta de Estrogênio/genética , Sobrevivência Celular , Antioxidantes/farmacologia , Chá , Receptor alfa de Estrogênio , Linhagem Celular Tumoral , Proliferação de Células
6.
J Microencapsul ; 41(5): 360-374, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38804967

RESUMO

Aim: To prepare sweet tea extract microcapsules (STEMs) via a spray-drying by applying different wall material formulations with maltodextrin (MD), inulin (IN), and gum arabic (GA). Methods: The microcapsules were characterised by yield, encapsulation efficiency (EE), particle size, sensory evaluation, morphology, attenuated total reflectance-Fourier transform infra-red spectroscopy and in vitro digestion studies. Results: The encapsulation improved the physicochemical properties and bioactivity stability of sweet tea extract (STE). MD5IN5 had the highest yield (56.33 ± 0.06% w/w) and the best EE (e.g. 88.84 ± 0.36% w/w of total flavonoids). MD9GA1 obtained the smallest particle size (642.13 ± 4.12 nm). MD9GA1 exhibited the highest retention of bioactive components, inhibition of α-glucosidase (96.85 ± 0.55%), α-amylase (57.58 ± 0.99%), angiotensin-converting enzyme (56.88 ± 2.20%), and the best antioxidant activity during in vitro gastrointestinal digestion. Conclusion: The encapsulation of STE can be an appropriate way for the valorisation of STE with improved properties.


Assuntos
Antioxidantes , Cápsulas , Goma Arábica , Inulina , Extratos Vegetais , Polissacarídeos , Chá , Polissacarídeos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Inulina/química , Chá/química , Goma Arábica/química , Antioxidantes/química , Antioxidantes/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/administração & dosagem , alfa-Amilases/química , Inibidores da Enzima Conversora de Angiotensina/química , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Tamanho da Partícula , Humanos , alfa-Glucosidases/química
7.
Crit Rev Food Sci Nutr ; : 1-25, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37493455

RESUMO

Tea contains a variety of bioactive components, including catechins, amino acids, tea pigments, caffeine and tea polysaccharides, which exhibit multiple biological activities. These functional components in tea provide a variety of unique flavors, such as bitterness, astringency, sourness, sweetness and umami, which meet the demand of people for natural plant drinks with health benefits and pleasant flavor. Meanwhile, the traditional process of tea plantation, manufacturing and circulation are often accompanied by the safety problems of pesticide residue, heavy metal, organic solvents and other exogenous risks. High-quality tea extract refers to the special tea extract obtained by enriching the specific components of tea. Through green and efficient extraction technologies, diversed high-quality tea extracts such as high-fragrance and high-amino acid tea extracts, low-caffeine and high-catechin tea extracts, high-bioavailability and high-theaflavin tea extracts, high-antioxidant and high-tea polysaccharide tea extracts, high-umami-taste and low-bitter and astringent taste tea extracts are produced. Furthermore, rapid detection, green control and intelligent processing are applied to monitor the quality of tea in real-time, which guarantee the stability and safety of high-quality tea extracts with enhanced efficiency. These emerging technologies will realize the functionalization and specialization of high-quality tea extracts, and promote the sustainable development of tea industry.


Main high-quality tea extracts and their preparation methods were introduced.Potential pollutants in the processing of tea extracts and their detection methods were proposed.Emerging intelligent processing technologies of tea extract were summarized.The applications of high-quality tea extracts in food industry were explored.Future trends of tea extracts and relevant suggestions were presented.

8.
Ecotoxicol Environ Saf ; 256: 114899, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37060801

RESUMO

Phenanthrene (Phe), one of the most frequently occurring pollutants in nature, can cause substantial damage to the human liver. Herbt Tea Essences (HTE), a kind of black tea extract with strong anti-inflammatory activity, can protect humans against disease. Currently, whether HTE can protect the liver from Phe-induced hepatotoxicity remains unclear. Herein, we explore the protective effects of HTE against Phe-induced hepatotoxicity. Our results showed that Phe exposure could significantly induce liver damage and increase serum hepatic enzyme levels in mice. HTE could prevent liver damage and recover the expression levels of inflammatory factors. Furthermore, we found that HTE suppressed the excessive activation of the nuclear transcription factor kappa-B and transforming growth factor-ß/SMAD signaling pathways to alleviate Phe-induced liver inflammation and fibrosis. Overall, our data showed that HTE treatment could be a new preventive means for Phe-induced liver disease.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Hepatopatias , Camundongos , Humanos , Animais , Extratos Vegetais/farmacologia , Fígado , NF-kappa B/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Chá
9.
Phytother Res ; 37(4): 1366-1376, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36729048

RESUMO

Chronic obstructive pulmonary disease (COPD) is an important lung disease characterized by complicated symptoms including emphysema. We aimed to explore the mechanisms underlying the protective effect of green tea extract (GTE) on cigarette smoke condensate (CSC)-induced emphysema by demonstrating the reduction of macrophage-induced protease expression through GTE treatment in vivo and in vitro. Mice were intranasally administered 50 mg/kg CSC once a week for 4 weeks, and doses of 100 or 300 mg/kg GTE were administered orally once daily for 4 weeks. GTE significantly reduced macrophage counts in bronchoalveolar lavage fluid and emphysematous lesions in lung tissues in CSC-exposed mice. In addition, GTE suppressed CSC-induced extracellular signal-regulated kinase (ERK)/activator protein (AP)-1 phosphorylation followed by matrix metalloproteinases (MMP)-9 expression as revealed by western blotting, immunohistochemistry, and zymography in CSC-instilled mice. These underlying mechanisms related to reduced protease expression were confirmed in NCI-H292 cells stimulated by CSC. Taken together, GTE effectively inhibits macrophage-driven emphysematous lesions induced by CSC treatment, and these protective effects of GTE are closely related to the ERK/AP-1 signaling pathway, followed by a reduced protease/antiprotease imbalance. These results suggest that GTE can be used as a supplementary agent for the prevention of emphysema progression in COPD patients.


Assuntos
Fumar Cigarros , Enfisema , Doença Pulmonar Obstrutiva Crônica , Enfisema Pulmonar , Camundongos , Animais , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Enfisema Pulmonar/complicações , Enfisema Pulmonar/metabolismo , Macrófagos , Antioxidantes/uso terapêutico , Enfisema/complicações , Extratos Vegetais/farmacologia , Peptídeo Hidrolases , Chá
10.
Crit Rev Food Sci Nutr ; : 1-29, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36533409

RESUMO

Diabetes mellitus is one of the major non-communicable diseases accounting for millions of death annually and increasing economic burden. Hyperglycemic condition in diabetes creates oxidative stress that plays a pivotal role in developing diabetes complications affecting multiple organs such as the heart, liver, kidney, retina, and brain. Green tea from the plant Camellia sinensis is a common beverage popular in many countries for its health benefits. Green tea extract (GTE) is rich in many biologically active compounds, e.g., epigallocatechin-3-O-gallate (EGCG), which acts as a potent antioxidant. Recently, several lines of evidence have shown the promising results of GTE and EGCG for diabetes management. Here, we have critically reviewed the effects of GTE and EGCC on diabetes in animal models and clinical studies. The concerns and challenges regarding the clinical use of GTE and EGCG against diabetes are also briefly discussed. Numerous beneficial effects of green tea and its catechins, particularly EGCG, make this natural product an attractive pharmacological agent that can be further developed to treat diabetes and its complications.

11.
Environ Res ; 204(Pt A): 111915, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34419472

RESUMO

For the optimization of silver nanoparticle production, a central composite design was used with three parameters: AgNO3 concentration, green tea extract concentration, and temperature at three different levels. The size of the synthesized silver nanoparticle, its UV absorbance, zeta potential, and polydispersity index were set as the response parameters. Silver nanoparticles obtained in the optimization process were characterized and its efficacy on colorimetric detection of mercury was evaluated. The response variables were significant for the factors analyzed, and each variable had a significant model (P < 0.05). The ideal conditions were: 1 mM AgNO3, 0.5% green tea extract, and 80 °C temperature. To analyze the produced AgNPs under certain ideal conditions, Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD) were used. The UV-visible spectra of AgNPs revealed an absorption maxima at 424 nm. The XRD pattern reveals a significant diffraction peak at 38.25°, 44.26°, 64.43°, and 77.49°, which corresponds to the (111), (200), (220), and (311) planes of polycrystalline face-centered cubic (fcc) silver, respectively. The TEM and SEM analyses confirmed that the particles were spherical, and dynamic light scattering study determined the average diameter of AgNPs to be 77.4 nm. The AgNPs have a zeta potential of -62.6 mV, as determined by the zeta sizer analysis. The AgNPs detects mercury at a micromolar concentration. Furthermore, the environmentally friendly generated AgNPs were used to detect mercury in a colorimetric method that was effectively employed for analytical detection of Hg2+ ions in an aqueous environment for the purpose of practical application.


Assuntos
Mercúrio , Nanopartículas Metálicas , Antibacterianos , Colorimetria , Resíduos Industriais , Extratos Vegetais , Prata , Chá , Águas Residuárias
12.
Arch Gynecol Obstet ; 306(2): 451-459, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35079875

RESUMO

PURPOSE: In the following work, we investigated the nuclear peroxisome proliferator-activated receptor gamma (PPARγ)-dependent proliferation behavior of breast cancer cells after stimulation with matcha green tea extract (MTE). METHODS: T47D cells were stimulated with MTE at concentrations of 5, 10 and 50 µg/ml. Cell viability was assessed using a WST-1 assay after an incubation time of 72 h. PPARγ expression was quantified at the gene level by real-time polymerase chain reaction (PCR). A western blot (WB) was carried out for the qualitative assessment of the expression behavior of on a protein level. RESULTS: The WST-1 test showed a significant inhibition of viability in T47D cells after 72 h at 5, 10 and 50 µg/ml. The PCR showed an overexpression of PPARγ in T47D cells in all concentrations. At the concentration of 50 µg/ml the expression was significantly increased (p < 0.05). The WB demonstrated a significant quantitative increase of PPARγ at protein level with MTE concentrations of 10 and 50 µg/ml. In addition, there was a negative correlation between the overexpression of PPAR γ and the inhibition of proliferation. CONCLUSION: MTE decreases the cell viability of T47D cells and furthermore leads to an overexpression of PPARγ on protein and mRNA level.


Assuntos
Neoplasias da Mama , PPAR gama , Extratos Vegetais , Neoplasias da Mama/tratamento farmacológico , Sobrevivência Celular , Feminino , Humanos , PPAR gama/genética , Extratos Vegetais/farmacologia , RNA Mensageiro/genética , Chá
13.
Molecules ; 27(23)2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36500365

RESUMO

Food extract supplements, with high functional activity and low side effects, play a recognized role in the adjunctive therapy of human colorectal cancer. The present study reported a new functional beverage, which is a type of Chinese Hakka stir-fried green tea (HSGT) aged for several years. The extracts of the lyophilized powder of five HSGT samples with different aging periods were analyzed with high-performance liquid chromatography. The major components of the extract were found to include polyphenols, catechins, amino acids, catechins, gallic acid and caffeine. The tea extracts were also investigated for their therapeutic activity against human colorectal cancer cells, HT-29, an epithelial cell isolated from the primary tumor. The effect of different aging time of the tea on the anticancer potency was compared. Our results showed that, at the cellular level, all the extracts of the aged teas significantly inhibited the proliferation of HT-29 in a concentration-dependent manner. In particular, two samples prepared in 2015 (15Y, aged for 6 years) and 2019 (19Y, aged for 2 years) exhibited the highest inhibition rate for 48 h treatment (cell viability was 50% at 0.2 mg/mL). Further, all the aged tea extracts examined were able to enhance the apoptosis of HT-29 cells (apoptosis rate > 25%) and block the transition of G1/S phase (cell-cycle distribution (CSD) from <20% to >30%) population to G2/M phase (CSD from nearly 30% to nearly 10%) at 0.2 mg/mL for 24 h or 48 h. Western blotting results also showed that the tea extracts inhibited cyclin-dependent kinases 2/4 (CDK2, CDK4) and CylinB1 protein expression, as well as increased poly ADP-ribose polymerase (PRAP) expression and Bcl2-associated X (Bax)/B-cell lymphoma-2 (Bcl2) ratio. In addition, an upstream signal of one of the above proteins, phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signalling, was found to be involved in the regulation, as evidenced by the inhibition of phosphorylated PI3K and AKT by the extracts of the aged tea. Therefore, our study reveals that traditional Chinese aged tea (HSGT) may inhibit colon cancer cell proliferation, cell-cycle progression and promoted apoptosis of colon cancer cells by inactivating PI3K/AKT signalling.


Assuntos
Camellia sinensis , Neoplasias do Colo , Neoplasias Colorretais , Humanos , Apoptose , Camellia sinensis/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Fosfatidilinositol 3-Quinase , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , Chá/química
14.
Molecules ; 27(12)2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35744897

RESUMO

Green synthesis of silver-containing nanocomposites based on polylactide (PLA) was carried out in two ways. With the use of green tea extract, Ag+ ions were reduced to silver nanoparticles with their subsequent introduction into the PLA (mechanical method) and Ag+ ions were reduced in the polymer matrix of PLA-AgPalmitate (PLA-AgPalm) (in situ method). Structure, morphology and thermophysical properties of nanocomposites PLA-Ag were studied by FTIR spectroscopy, wide-angle X-ray scattering (WAXS), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) methods. The antimicrobial, antiviral, and cytotoxic properties were studied as well. It was found that the mechanical method provides the average size of silver nanoparticles in the PLA of about 16 nm, while in the formation of samples by the in situ method their average size was 3.7 nm. The strong influence of smaller silver nanoparticles (3.7 nm) on the properties of nanocomposites was revealed, as with increasing nanosilver concentration the heat resistance and glass transition temperature of the samples decreases, while the influence of larger particles (16 nm) on these parameters was not detected. It was shown that silver-containing nanocomposites formed in situ demonstrate antimicrobial activity against gram-positive bacterium S. aureus, gram-negative bacteria E. coli, P. aeruginosa, and the fungal pathogen of C. albicans, and the activity of the samples increases with increasing nanoparticle concentration. Silver-containing nanocomposites formed by the mechanical method have not shown antimicrobial activity. The relative antiviral activity of nanocomposites obtained by two methods against influenza A virus, and adenovirus serotype 2 was also revealed. The obtained nanocomposites were not-cytotoxic, and they did not inhibit the viability of MDCK or Hep-2 cell cultures.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Nanocompostos , Antibacterianos/química , Anti-Infecciosos/farmacologia , Antivirais/farmacologia , Escherichia coli , Íons , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Nanocompostos/química , Poliésteres/química , Pseudomonas aeruginosa , Prata/química , Prata/farmacologia , Staphylococcus aureus
15.
Reprod Biol Endocrinol ; 19(1): 147, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34551795

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS), as the most common endocrine disorder in reproductive-aged women, is characterized by oxidative stress and ovarian tissue inflammation. Green tea extract (GTE) potentially possesses therapeutic effects for PCOS because of the antioxidant and anti-inflammatory compounds. This systematic review evaluates the potential roles of GTE on metabolic variables, hormone levels, and ovarian function in PCOS. METHODS: A systematic review was conducted of published studies reporting the effects of GTE on PCOS. Several major databases, including PubMed, SCOPUS, and Google Scholar, were searched up from inception to April 2021. Clinical trials and animal studies that assessed the effects of GTE on PCOS were eligible for inclusion. RESULTS: Of 314 articles found in the search, four human studies and four animal studies were included. All studies in humans showed the effects of GTE on weight loss. GTE's effect on decreasing testosterone levels in humans and LH levels in animals were also reported. In addition, increases in FSH and progesterone levels in animal models were observed. Although GTE improved fasting blood sugar and insulin levels, the effect of GTE on inflammatory parameters, such as TNF-alpha and IL-6 and antioxidant status, was limited to animal studies. CONCLUSION: Therefore, this review suggests that GTE could be considered a potential agent to attenuate PCOS complications mainly due to its effect on weight loss and glycemic levels. However, more studies are needed to formulate conclusions about the effects and mechanisms of GTE in PCOS.


Assuntos
Extratos Vegetais/farmacologia , Síndrome do Ovário Policístico/metabolismo , Chá/química , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Feminino , Humanos , Insulina/sangue , Resistência à Insulina , Estresse Oxidativo/efeitos dos fármacos , Fitoterapia/métodos , Extratos Vegetais/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/patologia
16.
FASEB J ; 34(8): 9995-10010, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32564472

RESUMO

Tea polyphenolics have been suggested to possess blood glucose lowering properties by inhibiting sugar transporters in the small intestine and improving insulin sensitivity. In this report, we studied the effects of teas and tea catechins on the small intestinal sugar transporters, SGLT1 and GLUTs (GLUT1, 2 and 5). Green tea extract (GT), oolong tea extract (OT), and black tea extract (BT) inhibited glucose uptake into the intestinal Caco-2 cells with GT being the most potent inhibitor (IC50 : 0.077 mg/mL), followed by OT (IC50 : 0.136 mg/mL) and BT (IC50 : 0.56 mg/mL). GT and OT inhibition of glucose uptake was partial non-competitive, with an inhibitor constant (Ki ) = 0.0317 and 0.0571 mg/mL, respectively, whereas BT was pure non-competitive, Ki  = 0.36 mg/mL. Oocytes injected to express small intestinal GLUTs were inhibited by teas, but SGLT1 was not. Furthermore, catechins present in teas were the predominant inhibitor of glucose uptake into Caco-2 cells, and gallated catechins the most potent: CG > ECG > EGCG ≥ GCG when compared to the non-gallated catechins (C, EC, GC, and EGC). In Caco-2 cells, individual tea catechins reduced the SGLT1 gene, but not protein expression levels. In contrast, GLUT2 gene and protein expression levels were reduced after 2 hours exposure to catechins but increased after 24 hours. These in vitro studies suggest teas containing catechins may be useful dietary supplements capable of blunting postprandial glycaemia in humans, including those with or at risk to Type 2 diabetes mellitus.


Assuntos
Antioxidantes/farmacologia , Catequina/farmacologia , Neoplasias do Colo/tratamento farmacológico , Transportador de Glucose Tipo 2/antagonistas & inibidores , Extratos Vegetais/farmacologia , Transportador 1 de Glucose-Sódio/antagonistas & inibidores , Chá/química , Animais , Células CACO-2 , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Feminino , Glucose/metabolismo , Humanos , Oócitos/efeitos dos fármacos , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Xenopus laevis
17.
Mar Drugs ; 19(3)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808933

RESUMO

In this work, a non-toxic chitosan-based carrier was constructed via genipin activation and applied for the immobilization of tannase. The immobilization carriers and immobilized tannase were characterized using Fourier transform infrared spectroscopy and thermogravimetric analysis. Activation conditions (genipin concentration, activation temperature, activation pH and activation time) and immobilizations conditions (enzyme amount, immobilization time, immobilization temperature, immobilization pH, and shaking speed) were optimized. The activity and activity recovery rate of the immobilized tannase prepared using optimal activation and immobilization conditions reached 29.2 U/g and 53.6%, respectively. The immobilized tannase exhibited better environmental adaptability and stability. The immobilized tannase retained 20.1% of the initial activity after 12 cycles and retained 81.12% of residual activity after 30 days storage. The catechins composition analysis of tea extract indicated that the concentration of non-ester-type catechins, EGC and EC, were increased by 1758% and 807% after enzymatic treatment. Biological activity studies of tea extract revealed that tea extract treated with the immobilized tannase possessed higher antioxidant activity, higher inhibitory effect on α-amylase, and lower inhibitory effect on α-glucosidase. Our results demonstrate that chitosan activated with genipin could be an effective non-toxic carrier for tannase immobilization and enhancing biological activities of tea extract.


Assuntos
Antioxidantes/farmacologia , Camellia sinensis , Hidrolases de Éster Carboxílico/metabolismo , Quitosana/química , Portadores de Fármacos , Inibidores de Glicosídeo Hidrolases/farmacologia , Iridoides/química , Extratos Vegetais/farmacologia , alfa-Amilases/antagonistas & inibidores , Antioxidantes/isolamento & purificação , Antioxidantes/metabolismo , Camellia sinensis/metabolismo , Hidrolases de Éster Carboxílico/química , Composição de Medicamentos , Estabilidade Enzimática , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Temperatura , Fatores de Tempo , alfa-Amilases/metabolismo
18.
Phytother Res ; 35(2): 996-1009, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32893422

RESUMO

This study was designed to assess bisphenol A (BPA)-induced vascular toxicity, the effectiveness of green tea extract and epigallocatechin gallate (EGCG) against BPA toxicity, and possible underlying mechanisms. In isolated rat aorta, contractile and relaxant responses as well as malondialdehyde levels were evaluated. Cell viability and effects on the protein levels of apoptotic (bax, bcl2, and caspase-3), autophagic (LC3), and cell adhesion molecules were calculated using the MTT method and western blotting in human umbilical vein endothelial cells (HUVECs). BPA increased aorta MDA levels (p < .0001) and decreased vascular responses to KCl [20 and 40 mM (p < .0001), 80 mM (p < .001)], phenylephrine [10-8 , 10-6 , and 10-5 M (p < .001), 10-7 and 10-4 M (p < .0001)], and acetylcholine [10-6 M (p < .01), 10-5 and 10-4 M (p < .0001)]. In HUVECs, BPA enhanced the levels of LC3A/B, bax/bcl2 ratio, cleaved caspase-3, and vascular cell adhesion molecule-1. Green tea extract, EGCG, and vitamin E co-treatment with BPA diminished the toxic effects of BPA. These findings provide evidence that green tea extract and EGCG possess beneficial effects in preventing BPA-induced vascular toxicity through increasing the antioxidant activities and the regulation of signaling pathways.


Assuntos
Antioxidantes/uso terapêutico , Aorta/efeitos dos fármacos , Compostos Benzidrílicos/efeitos adversos , Catequina/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Fenóis/efeitos adversos , Animais , Antioxidantes/farmacologia , Catequina/farmacologia , Catequina/uso terapêutico , Humanos , Masculino , Ratos , Ratos Wistar , Transdução de Sinais , Chá
19.
Arch Gynecol Obstet ; 303(5): 1235-1243, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33386959

RESUMO

PURPOSE: The daily ingestion of green tea extract (GTE) capsules in women with oligo- or asymptomatic uterine myomas was monitored over 6 months with regard to their quality of life, myoma-associated complaints and side effects. METHODS: The participants were interviewed and examined at the beginning of the study (T1) and then again after 6 months (T3). Quality of life was assessed using a SF-12 questionnaire while their myoma-associated complaints were ascertained by using a self-developed myoma symptom questionnaire. Changes in the size of the myomas were evaluated by vaginal sonography. Side effects after 3 months (T2) and 6 months were documented by systematic interviews. RESULTS: Overall; 25 participants (median 45 years) have been enrolled. The analysis of the SF-12 questionnaire showed a significant improvement of the physical cumulative score of the SF-12 during the 6 month GTE capsule ingestion (T1: mean value (M) = 52.731; 95% confidence interval (KI95%): 49.791-55.671; T3: M = 55.862; KI95%%: 55.038-56.685; p = 0.019). However, the mental cumulative score of the SF-12 did not change significantly (p = 0.674). No significant correlation could be established between the capsule ingestion and changes in the symptom questionnaire, the laboratory parameters nor the myoma size. No relevant adverse side effects were reported. CONCLUSION: Women who took GTE capsules showed a significant improvement in their physical cumulative score on the SF-12, but not in the global QoL score. Myoma size or other objective parameters did not change.


Assuntos
Catequina/análogos & derivados , Leiomioma/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Qualidade de Vida/psicologia , Chá/química , Adulto , Cápsulas , Catequina/farmacologia , Catequina/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Extratos Vegetais/farmacologia
20.
Int J Mol Sci ; 22(24)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34948464

RESUMO

Functional studies of organisms and human models have revealed that epigenetic changes can significantly impact the process of aging. Non-coding RNA (ncRNA), one of epigenetic regulators, plays an important role in modifying the expression of mRNAs and their proteins. It can mediate the phenotype of cells. It has been reported that nc886 (=vtRNA2-1 or pre-miR-886), a long ncRNA, can suppress tumor formation and photo-damages of keratinocytes caused by UVB. The aim of this study was to determine the role of nc886 in replicative senescence of fibroblasts and determine whether substances capable of controlling nc886 expression could regulate cellular senescence. In replicative senescence fibroblasts, nc886 expression was decreased while methylated nc886 was increased. There were changes of senescence biomarkers including SA-ß-gal activity and expression of p16INK4A and p21Waf1/Cip1 in senescent cells. These findings indicate that the decrease of nc886 associated with aging is related to cellular senescence of fibroblasts and that increasing nc886 expression has potential to suppress cellular senescence. AbsoluTea Concentrate 2.0 (ATC) increased nc886 expression and ameliorated cellular senescence of fibroblasts by inhibiting age-related biomarkers. These results indicate that nc886 has potential as a new target for anti-aging and that ATC can be a potent epigenetic anti-aging ingredient.


Assuntos
Metilação de DNA , Regulação para Baixo , Fibroblastos/citologia , Marcadores Genéticos , Proliferação de Células , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Metilação de DNA/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Marcadores Genéticos/efeitos dos fármacos , Humanos , MicroRNAs/genética , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Chá/química
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