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This study aimed to examine the dose–response effects of polyphenon-60 derived from green tea (P60-GT) on hexavalent chromium [Cr(VI)]-induced genotoxic damage and apoptosis. Male Hsd:ICR mice were divided into 4 groups: (1) Control (vehicle only), (2) P60-GT (15, 30, or 45 mg/kg gavage), (3) Cr(VI) (20 mg/kg of CrO3 intraperitoneally), and (4) P60-GT+CrO3 (P60-GT administered 4 hr before CrO3). Peripheral blood samples were collected at 24, 48, and 72 hr to assess the number of micronuclei (MN), apoptosis, and cell viability, while plasma 8-hydroxy-2’-deoxyguanosine (8-OHdG) levels were measured at 0 and 48 hr. Cr(VI) significantly increased MN frequency, suppressed 8-OHdG repair, and reduced cell viability. Pre-treatment with P60-GT reduced MN frequency by up to 74%, with the 30 mg/kg dose demonstrating the highest efficacy. This dose restored cell viability, enhanced 8-OHdG repair, and enhanced apoptosis, suggesting activation of DNA repair and apoptotic pathways as potential antigenotoxic mechanisms. The 15 mg/kg dose exhibited anti-apoptotic effects, while the 30 and 45 mg/kg doses promoted apoptosis. However, the 45 mg/kg dose resulted in 100% lethality by 72 hr, likely due to synergistic toxicity with Cr(VI). These findings demonstrate the dose-dependent protective effects of P60-GT and emphasize the need for dosage optimization to maximize therapeutic benefits while minimizing toxicity. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to evaluate the effects of green tea catechins on the prevention of Parkinson's disease neurobehavioral symptoms and α-synuclein blood plasma concentration in a hemizygous transgenic A53T mouse model.Methods: Thirty 6-month-old male mice were randomly assigned to three groups (n = 10/group): control, low-dose, and high-dose, receiving green tea polyphenol (GTP) treatment in their drinking water at 0%, 0.5%, and 1.5%, respectively, over a 90-day period. The efficacy of ad libitum dosing was assessed by analyzing the bioaccumulation of tea catechins in urine samples collected from metabolic cages on days 0, 30, 60, and 90, using LC/Q-TOF analysis. PD-related behavioral impairments were measured with open field and rotarod performance tests on days 0, 45, and 90. On day 90, plasma α-synuclein levels were analyzed via enzyme-linked immunosorbent assay (ELISA) to assess treatment effects.Results: Circulating tea catechin metabolites were detected in treated groups by day 30, with levels progressively increasing through day 90. By day 90, control mice exhibited significant deficits in rotarod performance, while both low- and high-dose groups maintained or improved their maximum time on the rotarod. Open field testing indicated reduced anxiety-related behavior in control mice compared to treated groups. ELISA analysis revealed significantly lower circulating α-synuclein levels in high-dose mice compared to controls.Conclusion: Our findings indicate that sustained administration of tea catechins significantly reduces circulating α-synuclein levels in blood plasma, improves motor coordination in a dose-dependent manner, and modulates anxiety-related behaviors in a PD mouse model. [ABSTRACT FROM AUTHOR]

Pulmonary hypertension, a common complication of chronic obstructive pulmonary disease, is a major global health concern. Green tea is a popular beverage that is consumed all over the world. Green tea's active ingredients are epicatechin derivatives, also known as "polyphenols," which have anti-carcinogenic, anti-inflammatory, and antioxidant properties. This study aimed to explore the possible mechanism of green tea polyphenols in the treatment of pulmonary hypertension using network pharmacology, molecular docking, and experimental verification. A total of 316 potential green tea polyphenols-related targets were obtained from the PharmMapper, SwissTargetPrediction, and TargetNet databases. A total of 410 pulmonary hypertension-related targets were predicted by the CTD, DisGeNET, pharmkb, and GeneCards databases. Green tea polyphenols-related targets were hit by the 49 targets associated with pulmonary hypertension. AKT1 and HIF1-α were identified through the FDA drugs-target network and PPI network combined with GO functional annotation and KEGG pathway enrichment. Molecular docking results showed that green tea polyphenols had strong binding abilities to AKT1 and HIF1-α. In vitro experiments showed that green tea polyphenols inhibited the proliferation and migration of hypoxia stimulated pulmonary artery smooth muscle cells by decreasing AKT1 phosphorylation and downregulating HIF1α expression. Collectively, green tea polyphenols are promising phytochemicals against pulmonary hypertension. [ABSTRACT FROM AUTHOR]

Introduction: Di(2-ethylhexyl) phthalate (DEHP) is a common plasticizer. Studies have revealed that DEHP exposure can cause kidney damage. Green tea is among the most popular beverages in China. Green tea polyphenols (GTPs) have been proven to have therapeutic effects on organ damage induced by heavy metal exposure. However, few studies have reported on GTP-relieving DEHP-induced kidney damage. Methods: C57BL/6J male mice aged 6–8 weeks were treated with distilled water (control group), 1,500 mg/kg/d DEHP + corn oil (model group), 1,500 mg/kg/d DEHP + corn oil + 70 mg/kg GTP (treatment group), corn oil (oil group), and 70 mg/kg GTP (GTP group) by gavage for 8 weeks, respectively. The renal function of mice and renal tissue histopathology of each group were evaluated. The renal tissues of mice in the model, treatment, and control groups were analyzed using high-throughput sequencing. We calculated the differentially expressed microRNAs (miRNAs) and messenger RNAs (mRNAs) using the limma R package, the CIBERSORT algorithm was used to predict immune infiltration, the starBase database was used to screen the miRNA-mRNA regulatory axis, and immunohistochemical analyses were performed to verify protein expression. Results: GTP alleviated the deterioration of renal function, renal inflammation and fibrosis, and mitochondrial and endoplasmic reticulum lesions induced by DEHP in mice. Differential immune infiltrations of plasma, dendritic, T, and B cells were noted between the model and treatment groups. We found that three differentially expressed miRNAs (mmu-miR-383-5p, mmu-miR-152-3p, and mmu-miR-144-3p), three differentially expressed mRNAs (Ddit4, Dusp1, and Snx18), and three differentially expressed proteins (Ddit4, Dusp1, and Snx18) played crucial roles in the miRNA-mRNA-protein regulatory axes when GTPs mitigate DEHP-induced kidney damage in mice. Conclusion: GTP can alleviate DEHP-induced kidney damage and regulate immune cell infiltration. We screened four important miRNA-mRNA-protein regulatory axes of GTP, mitigating DEHP-induced kidney damage in mice. [ABSTRACT FROM AUTHOR]

In this study, the physiochemical characters including moisture content variation, pH, total soluble solids (TSS), color, ascorbic acid content, total polyphenols, and antioxidant activities of mango powder fortified with green tea polyphenols (GTP) were investigated during storage for 90 d. Our results indicated stable colors of mango powder were found after GTP addition. GTP also inhibited the destruction of ascorbic acid during processing, and decreased its degradation rate during the whole storage. The total polyphenols of mango powder stored at 4 ℃ and room temperature decreased by 37.85% and 51.79%, respectively. After addition with GTP, the total polyphenols decreased only by 7.89%, and 13.31%, respectively. The antioxidant activities rose by 1.6 to 4.6-fold after GTP addition, and it decreased at a slower rate compared to that of unfortified mango powder. Correlation analysis indicated that EGCG might be the main substance that retain the physiochemical stability of mango powder.

This review is based upon evidence from the published effects of green tea polyphenols (GTP) on genotoxic damage induced by metals with carcinogenic potential. First, the relationship between GTP and antioxidant defense system is provided. Subsequently, the processes involved in the oxidative stress generated by metals and their relationship to oxidative DNA damage is examined. The review demonstrated that GTP generally decrease oxidative DNA damage induced by exposure to metals such as arsenic (As), cadmium (Cd), cobalt (Co), copper (Cu), chromium (Cr), iron (Fe), and lead (Pb). The pathways involved in these effects are related to: (1) direct scavenging of free radicals (FR); (2) activation of mechanisms to repair oxidative DNA damage; (3) regulation of the endogenous antioxidant system; and (4) elimination of cells with genetic damage via apoptosis. The results obtained in the studies reviewed demonstrate potential for possible use of GTP to prevent and treat oxidative damage in populations exposed to metals. Further, GTP may be considered as adjuvants to treatments for metal-associated diseases related to oxidative stress and DNA damage. [ABSTRACT FROM AUTHOR]

We previously showed that green tea polyphenols (GTPs) exert antiadipogenic effects on preadipocyte proliferation. Here, we investigated the regulatory effects of GTPs on osteogenesis and adipogenesis during early differentiation of human adipose tissue-derived stem cells (hADSC). Adipogenesis of hADSCs was determined by oil-red-O staining and triglycerides synthesis measurement. Osteoporosis of hADSC was measured using alkaline phosphatase assays and intracellular calcium levels. Immunofluorescence staining and qRT-PCR were used to detect PPARγ-CEBPA regulated adipogenic pathway regulated by PPAR-CEBPA and the osteogenic pathway mediated by RUNX2-BMP2. We found that GTPs treatment significantly decreased lipid accumulation and cellular triglyceride synthesis in mature adipocytes and attenuated pioglitazone-induced adipogenesis in a dose-dependent manner. GTPs downregulated protein and mRNA expression of Pparγ and attenuated pioglitazone-stimulated-Cebpa expression. GTPs treatment significantly enhanced hADSCs differentiation into osteoblasts compared to control and pioglitazone-treated cells. GTPs upregulated RunX2 and Bmp2 proteins and mRNA expression compared to control and significantly attenuated decreased RunX2 and Bmp2 mRNA expression by pioglitazone. In conclusion, our data demonstrates GTPs possesses great ability to facilitate osteogenesis and simultaneously inhibits hADSC differentiation into adipogenic lineage by upregulating the RUNX2-BMP2 mediated osteogenic pathway and suppressing PPARγ-induced signaling of adipogenesis. These findings highlight GTPs’ potential to combat osteoporosis associated with obesity.

Background: Coronavirus disease (COVID-19) outbreak prompts the world to develop novel drugs to treat the disease. Targeting the virus protein has attracted a great interest in COVID-19 drug discovery. The 3-chymotrypsin-like cysteine protease (3CLpro) of SARS-CoV-2 protein is one of the promising targets for its important role in viral replication. Various efforts have been made to find a specific therapeutic for COVID-19, including those derived from plants as anti-COVID-19. Green tea (Camellia sinensis L.) contains polyphenols which have been known for their health benefits. Objectives: This study aims to discover the activity of green tea polyphenols as 3CLpro of SARS-CoV-2 inhibitor in silico which may be applied to treat COVID-19. Methodology: The research was conducted using molecular docking and molecular dynamics simulation. Results: The molecular docking study of green tea polyphenols in complex with 3CLpro of SARS-CoV-2 (PDB: 7C8T) showed that gallocatechin-3-gallate (GCG) and catechin-gallate (CG) have binding free energy (ΔG) lower than reference ligand. Complex of GCG and 3CLpro of SARS-CoV-2 appears very stable and also has the lowest flexibility compared to CG and reference ligand based on root mean square deviation and root mean square fluctuation plot analysis using molecular dynamic simulation. Conclusion: This study concludes that GCG has potential to be developed as a 3CLpro of SARS-CoV-2 inhibitor. [ABSTRACT FROM AUTHOR]

Oat milk has become preferential because of its low calorie nature and high dietary fiber content, but its ability to "curdle" when mixed with tea can affect the consumer acceptability for oat milk tea. In this study, a model system for oat milk tea was made by combining oat milk and green tea extract to evaluate the impacts of the oat milk matrix and green tea extract concentration on the stability and polyphenol bioaccessibility. The stability analysis results showed that adding green tea extract to oat milk influenced the stability of the oat milk tea model systems. In contrast, the 3.0% fat oat milk tea model system exhibited a higher stability than the 1.5% fat oat milk tea model system. In simulated gastrointestinal digestive experiments, tea polyphenols in the oat milk tea model systems were relatively stable in oral and stomach digestive stages, while they clearly degraded in the small intestine digestive stage. Furthermore, the bioaccessibility of tea polyphenols was higher for the 3.0% fat oat milk tea model system than for the 1.5% fat oat milk tea model system, especially at low concentrations of green tea extracts (0.05%~0.25%). These results may provide a theoretical reference and data for the formulation of oat milk tea and the bioaccessibility of tea polyphenols in food matrices. [ABSTRACT FROM AUTHOR]

This study investigated the potential of alginate edible films to act as vehicles for the delivery of polyphenols to the intestinal tract. Sodium alginate (0.5–2% w/v) and green tea extract (GTE, 25–50% w/w) were combined to form films with different microstructural properties via the casting method, where their physical, mechanical and barrier properties were analysed. Release studies into a 50% ethanol (v/v) food simulant and under simulated in vitro digestion were also conducted, and the resulting kinetics of polyphenols release was investigated. Composite alginate films with 25% w/w GTE (E∼2500 MPa; EAB∼14%; k∼0.04) showed significantly enhanced mechanical properties and slower rates of polyphenol release than samples with 50% w/w GTE (E∼6000 MPa; EAB∼6%; k∼0.18). Polyphenols entrapped within the 2% alginate – GTE films were successfully released during digestion (∼54%), demonstrating their bioaccessibility and availability for absorption by the gastrointestinal tract. The bioaccessibility of green tea polyphenols was significantly enhanced by films with good sustained-release effect (2% alginate – GTE, C/C 0 = 54.41 ± 0.75%) respect to the free GTE (C/C 0 = 33.73 ± 6.57%). These findings highlight the versatility of bioactive alginate edible films and create a blueprint for the design of sustainable active packaging alternatives with dual functionality. [Display omitted] • Green tea polyphenols entrapped within alginate film networks were bioaccessible. • Crosslinking with polyphenols enhanced the mechanical properties of alginate films. • Alginate entanglement and crosslinking dictated the rate of polyphenol release. • Alginate films with sustained-release effect enhanced polyphenols bioaccessibility. [ABSTRACT FROM AUTHOR]

Breast cancer (BC) is the most common malignancy and the second leading cause of cancer death among women in the United States. The consumption of natural dietary components such as broccoli sprouts (BSp) and green tea polyphenols (GTPs) has demonstrated exciting potential in reducing the risk of BC through the regulation of epigenetic mechanisms. However, little is known about their impacts on reversing epigenomic aberrations that are centrally involved in the initiation and progression of BC. Previously, we have determined the efficacy of combined BSp and GTPs treatment on the inhibition of the growth of a mammary tumor in a transgenic Her2/neu mouse model. We sought to extend our previous study to identify universal biomarkers that represent common mechanistic changes among different mouse models in response to this dietary regime by including a new transgenic mouse model, C3(1)-SV40 TAg (SV40). As a result, we identified novel target genes that were differentially expressed and methylated in response to dietary botanicals when administered singly (BSp and GTPs) and in combination (BSp + GTPs) in both mouse models. We discovered more differentially expressed and methylated genes in the combination treatment group compared to the singly administered groups. Subsequently, several biological pathways related to epigenetic regulations were identified in response to the combination treatment. Furthermore, when compared to the BSp and GTPs treatment alone, the combinatorial treatment showed a more significant impact on the regulation of the epigenetic modifier activities involved in DNA methylation and histone modifications. Our study provides key insights about the impact of the combined administration of BSp and GTPs on BC using a multi-omics analysis, suggesting a combinatorial approach is more efficacious in preventing and inhibiting BC by impacting key tumor-related genes at transcriptomic and methylomic levels. Our findings could be further extrapolated as a comprehensive source for understanding the epigenetic modifications that are associated with the effects of these dietary botanicals on BC prevention. [ABSTRACT FROM AUTHOR]

Previous studies have revealed that green tea polyphenol (GTP) could protect against liver injury due to oxidative stress. However, the mechanism underlying the bioactive actions of GTP in the liver has not been systematically evaluated. This study aimed to investigate the effect of GTP on the activation of the nuclear factor erythroid-2-related factor 2 (Nrf2)-Kelch-like ECH-associated protein 1 (keap1) pathway, using in silico and in vivo methods. Furthermore, the regulation of Nrf2 downstream target antioxidant response element (ARE) was also evaluated. The high-performance liquid chromatography analysis indicated that GTP includes 9 major compounds, and molecule docking analysis demonstrated that most of these polyphenols have a strong binding affinity with the keap1 Kelch domain, where keap1 binds to the Neh2 domain of Nrf2. Remarkably, the predominant compound of GTP, that is, epigallocatechin gallate, displayed the best binding affinity score, which can fully occupy all 3 polar subpockets of the keap1 Kelch domain. The Nrf2, keap1, and Nrf2 downstream target gene expression levels were changed in the livers compared to the control group. It showed that the Nrf2 expression level was significantly upregulated in GTP-induced mice liver across most treatments, while the keap1 expression level remained unchanged. Subsequently, we observed a significant increasing trend in the expression of the downstream ARE, including antioxidative enzymes, liver phase II enzymes, and liver efflux transporters in mice livers. The present study demonstrated that GTP could activate the Nrf2 signaling pathway by interrupting the Nrf2-keap1 protein–protein interaction [ABSTRACT FROM AUTHOR]

• Norovirus infection causes 21 million cases of gastroenteritis in the US each year. • Alcohol is ineffective against norovirus and other alcohol-resistant microorganisms. • Green tea-derived compounds significantly enhanced the virucidal activity of alcohol. • Ingredients found in beverages increase virucidal activity in surface disinfectants. • Epigallocatechin-3-gallate-palmitates add benefits to hand hygiene formulations. Non-toxic hand hygiene and surface disinfectant products with virucidal activity against alcohol-resistant nonenveloped norovirus are in urgent need. Alcohol-based formulations were made with epigallocatechin-3-gallate-palmitate (EC16), an FDA accepted food additive. Based on in-house testing of formulations, 3 prototypes, PTV80 hand gel, PST70 surface disinfectant spray and PST70 surface disinfectant wipe, were selected from in-house tests for independent testing at GLP (good laboratory practice) laboratories according to EN 14476:2019 (hand gel), ASTM test method E1053-20 (spray), and ASTM E2362-15, E1053, and ASTM E2896-12 (wipe). The PTV80 hand gel prototype demonstrated a >99.999% reduction of murine norovirus S99 infectivity in 60 seconds. Carrier testing of the PST70 surface spray and surface wipe demonstrated reduction of feline calicivirus infectivity by >99.99% in 60 seconds. In addition, testing with human coronavirus and human herpes simplex virus demonstrated >99.99% efficacy in 60 seconds, consistent with broad spectrum virucidal activity. The novel non-toxic prototypes containing EC16 were found to be suitable for use in future hand sanitizer gel, surface disinfectant spray and wipe products against norovirus. Products based on these formulations could be used safely to help prevent and control norovirus and other emerging virus outbreaks, pending future studies. [ABSTRACT FROM AUTHOR]

Background: Di(2-ethylhexyl) phthalate (DEHP) is a commonly used plasticizer known for its toxic effects on the male reproductive system. Green tea polyphenols (GTPs), recognized for their antioxidant and anti-inflammatory properties, have demonstrated protective effects on various organs, but the mechanisms by which GTPs mitigate DEHP-induced testicular damage remain unclear., Methods: Healthy male C57BL/6 J mice were divided into five groups: Control, DEHP, DEHP + GTP treatment, GTP, and Oil groups. Testicular histopathological changes were assessed using hematoxylin-eosin (H&E), periodic acid-Schiff (PAS), and Masson staining. Ultrastructural alterations were examined through transmission electron microscopy. High-throughput sequencing was performed to analyze the expression of mRNA, miRNA, and lncRNA, and to construct an lncRNA-miRNA-mRNA regulatory network for identifying key regulatory axes., Results: Mice in the DEHP group exhibited significant testicular damage, including reduced sperm count, mitochondrial deformation, and endoplasmic reticulum dilation. GTP treatment notably improved testicular structural integrity, restored sperm count, and alleviated mitochondrial and endoplasmic reticulum damage. Additionally, DEHP significantly increased activated CD8+ T cells, which were reduced with GTP treatment. High-throughput sequencing revealed that GTP treatment exerted protective effects through the regulation of six key lncRNA-miRNA-mRNA axes., Conclusion: GTPs significantly protect against DEHP-induced testicular damage, and the lncRNA-miRNA-mRNA regulatory axes play a potential role in this process., (© The Author(s) 2024. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

In-depth insights in cancer biology over the past decades have highlighted the important roles of epigenetic mechanisms in the initiation and progression of tumorigenesis. The cancer epigenome usually experiences multiple alternations, including genome-wide DNA hypomethylation and site-specific DNA hypermethylation, various histone posttranslational modifications, and dysregulation of non-coding RNAs (ncRNAs). These epigenetic changes are plastic and reversible, and could potentially occur in the early stage of carcinogenesis preceding genetic mutation, offering unique opportunities for intervention therapies. Therefore, targeting the cancer epigenome or cancer epigenetic dysregulation with some selected agents (called epi-drugs) represents an evolving and promising strategy for cancer chemoprevention and therapy. Phytochemicals, as a class of pleiotropic molecules, have manifested great potential in modulating different cancer processes through epigenetic machinery, of which green tea polyphenol epigallocatechin-3-gallate (EGCG) is one of the most extensively studied. In this review, we first summarize epigenetic events involved in the pathogenesis of cancer, including DNA/RNA methylations, histone modifications and ncRNAs' dysregulations. We then focus on the recently discovered roles of phytochemicals, with a special emphasis on EGCG, in modulating different cancer processes through regulating epigenetic machinery. We finally discuss limitations of EGCG as an epigenetic modulator for cancer chemoprevention and treatment and offer potential strategies to overcome the shortcomings. [ABSTRACT FROM AUTHOR]

Enterococcus faecasslis (E. faecalis) is a resident bacterium in the host. The increase in internal stress like low pH may affect the biological effects of E. faecalis. The prebiotic‐like function of tea polyphenols can enhance the beneficial effects of its tolerance to environmental stress. In this study, RNA‐sequence analysis was used to explore the protective effect of green tea polyphenols (GTP) on E. faecalis under low pH stress. A total of 28 genes were found to be responsive to GTP under low pH stress, including 16 up‐regulated and 12 down‐regulated. GTP intervention can partly relieve some undesired negative influences, such as the down‐regulation of the base excision repair gene and amino acid transport and metabolism gene. The significantly changes were associated with selenocompound metabolism and aminoacyl‐tRNA biosynthesis after the intervention of GTP. The present study provided new insights into the growth and continuous adaptation of E. faecalis under stress. [ABSTRACT FROM AUTHOR]

The aim of this study is to characterize and increase the total soluble (water soluble + alcohol soluble) phenolic (SPCT) and flavonoid content (SFCT) and total soluble free radical scavenging based antioxidant capacity (SACT) of major sun-dried fruits such as raisins, figs, prunes and apricots. Due to their high insoluble dietary fiber content, the bound antioxidant capacity formed 61 to 67% of the overall antioxidant capacity (water soluble + alcohol soluble + bound) of sun-dried fruits. The SPCT, SFCT and SACT of sun-dried fruits changed between 1675 and 3860 µg catechin/g (d.w.), 161 and 495 µg catechin/g (d.w.) and 13 and 28.5 µmol Trolox/kg (d.w.), respectively. The incorporation of green tea polyphenols into sun-dried raisins, figs and apricots by controlled rehydration conducted in green tea extracts increased their SPCT, SFCT and SACT 1.5 to 1.8 fold, 1.3 to 1.6 fold, and 1.5 to 2.6 fold, respectively. The method applied caused limited increases in SPCT (1.1 fold) and SFCT (1.2 fold) of prunes, but it increased SACT of these fruits 1.6 fold. This study showed the possibility of using sun-dried fruits not only as source of dietary fiber, but also for delivery of phenolic compounds. The methods used in this study for delivery of green tea phenolic compounds to selected organic sundried fruits could be an alternative method to increase intake of these invaluable antioxidant compounds and increase functionality of sun-dried fruits which are already accepted as good source of dietary fiber. [ABSTRACT FROM AUTHOR]

Ulcerative colitis (UC) is one of the inflammatory bowel diseases (IBD) that result in recurrent inflammation plus ulcers of the colon and rectum. Recently, mesenchymal stem cell-derived exosomes MSC-EXs have shown a lot of promise for the treatment of gut disorders, with cell regeneration and angiogenesis. Green tea polyphenols (GTPs) display specific beneficial effects on health and pathologies. The aim of this study was to explore the possible effect of MSC-EXs and GTPs on acetic acid-induced UC in rats. Sixty adult male rats were divided into five groups: group I, control group; group II, UC; group ΙIΙ, UC treated with GTPs; group ΙV, UC treated with MSC-EXs; and group V, UC treated with combined GTPs and MSC-EXs. Colonic samples were processed for histological and immunohistochemical methods. Expression of CXCR2 and TLR4 levels was measured. Groups ΙI and III showed ulceration, loss of surface columnar epithelium, disturbed crypt architecture with few goblet cells, and many cellular infiltrations with the overexpression of CXCR2 and TLR4. Group IV showed attenuation of some histological changes. Group V showed improvement of the most histological and immunohistochemical changes described previously. MSC-EXs represent future therapeutic hopes for chronic intestinal inflammatory states, keeping the integrity of innate immunity through their regenerative and anti-inflammatory effects. The combination of GTPs and MSC-EXs was more effective and produced an additive effect than using MSC-EXs alone. [ABSTRACT FROM AUTHOR]

Oat milk has become preferential because of its low calorie nature and high dietary fiber content, but its ability to “curdle” when mixed with tea can affect the consumer acceptability for oat milk tea. In this study, a model system for oat milk tea was made by combining oat milk and green tea extract to evaluate the impacts of the oat milk matrix and green tea extract concentration on the stability and polyphenol bioaccessibility. The stability analysis results showed that adding green tea extract to oat milk influenced the stability of the oat milk tea model systems. In contrast, the 3.0% fat oat milk tea model system exhibited a higher stability than the 1.5% fat oat milk tea model system. In simulated gastrointestinal digestive experiments, tea polyphenols in the oat milk tea model systems were relatively stable in oral and stomach digestive stages, while they clearly degraded in the small intestine digestive stage. Furthermore, the bioaccessibility of tea polyphenols was higher for the 3.0% fat oat milk tea model system than for the 1.5% fat oat milk tea model system, especially at low concentrations of green tea extracts (0.05%~0.25%). These results may provide a theoretical reference and data for the formulation of oat milk tea and the bioaccessibility of tea polyphenols in food matrices.

Oxidative stress (OS) is one of the main limiting factors affecting the length of lactation and milk quality in dairy cows. For high-producing dairy cows, the OS of mammary glands is a serious problem. Green tea polyphenols (GTP), found mainly in tea, are a combination of many phenols. GTP have a good effect on antioxidation, inflammation resistance, obesity, fat cell metabolism improvement, and lowering of blood lipid. Therefore, we studied the role of GTP on OS in dairy cows and further investigated whether GTP alleviates oxidative damage of bovine mammary epithelial cells (BMECs) induced by hydrogen peroxide (H2O2) and its underlying molecular mechanism. In this study, 500 μM of H2O2 for 12 h incubation was chosen as the condition of the OS model of BMECs. In addition, the present results found that treatment with GTP alleviated the oxidative damage induced by H2O2 [the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) were significantly increased, and the contents of malondialdehyde (MDA), 8-isoprostaglandin (8-iso-PG), 8-oxo-deoxyguanosine (8-OHdG), and protein carbonyl (PC) and caspase-3 and caspase-9 activities were significantly reduced]. These effects are related to the activation of the erythrocyte-derived nuclear factor 2-like protein 2 (NFE2L2) signaling pathway and the inactivation of the caspase/Bcl-2 apoptotic pathway. When NFE2L2 short interfering RNA (siRNA) was used to downregulate the expression of NFE2L2 in cultured BMECs, NFE2L2-siRNA transfection abolished the protective effect of GTP on H2O2-induced intracellular reactive oxygen species (ROS) accumulation and apoptosis. In addition, the mitogen-activated protein kinase (MAPK) inhibition test further proved that GTP relieved H2O2-induced oxidative damage by activating the NFE2L2 signaling pathway, which was achieved by activating the extracellular-regulated kinase 1/2 (ERK1/2) signaling pathway. Overall, the results indicate that GTP has a beneficial effect on the redox balance of BMECs. In addition, GTP might be a latent antioxidant in vivo, which can be administered to ruminants during stressful periods such as the perinatal period.

Although the evidence is inconclusive, epidemiological studies strongly suggest that increased exposure to electromagnetic radiation (EMR) increases the risk of brain tumors, parotid gland tumors, and seminoma. The International Agency for Research on Cancer (IARC) has classified mobile phone radiofrequency radiation as possibly carcinogenic to humans (Group 2B). Humans being are inadvertently being exposed to EMR as its prevalence increases, mainly through mobile phones. Radiation exposure is unavoidable in the current context, with mobile phones being an inevitable necessity. Prudent usage of medicinal plants with a long history of mention in traditional and folklore medicine and, more importantly, are safe, inexpensive, and easily acceptable for long-term human use would be an appealing and viable option for mitigating the deleterious effects of EMR. Plants with free radical scavenging, anti-oxidant and immunomodulatory properties are beneficial in maintaining salubrious health. Green tea polyphenols, Ginkgo biloba, lotus seedpod procyanidins, garlic extract, Loranthus longiflorus, Curcuma amada, and Rosmarinus officinalis have all been shown to confer neuroprotective effects in validated experimental models of study. The purpose of this review is to compile for the first time the protective effects of these plants against mobile phone-induced neuronal damage, as well as to highlight the various mechanisms of action that are elicited to invoke the beneficial effects. [ABSTRACT FROM AUTHOR]

Green Tea polyphenols (GTP) are important bioactive compounds with excellent physiological regulation functions. However, they are easily destroyed by the gastric environment during digestion. In this work, a sodium alginate (SA)-gellan gum (GG) interpenetrating network (IPN) hydrogel was synthesized to protect and delivery GTP. The ratio of SA/GG significantly affects the network structure of IPN hydrogels and the performance of delivering GTP. The hydrogel formed by interpenetrating 20 % GG with 80 % SA as the main network had the highest water uptake (55 g/g), holding capacity (950 mg/g), and freeze-thaw stability, with springiness reaching 0.933 and hardness reaching 1300 g, which due to the filling effect and non-covalent interaction. Rheological tests showed that the crosslink density of IPN hydrogel in SA-dominated network was improved by the addition of GG to make it better bound to GTP, and the higher water uptake meant that the system could absorb more GTP-containing solution. This IPN hydrogel maintained 917.3 mg/g encapsulation efficiency at the highest loading capacity (1080 mg/g) in tests as delivery system. In in vitro digestion simulations, owing to the pH responsiveness, the IPN hydrogel reduced the loss of GTP in gastric fluid, achieving a bioaccessibility of 71.6 % in the intestinal tract. [Display omitted] [ABSTRACT FROM AUTHOR]

Angiogenin (Ang), is a ribonucleolytic protein that is associated with angiogenesis, the formation of blood vessels. The involvement of Ang in vascularisation makes it a potential target for the identification of compounds that have the potential to inhibit the process. The compounds may be assessed for their ability to inhibit the ribonucleolytic activity of the protein and subsequently blood vessel formation, a crucial requirement for tumor formation. We report an inhibition of the ribonucleolytic activity of Ang with the gallate containing green tea polyphenols, ECG and EGCG that exhibits an increased efficacy upon forming polyphenol‐capped gold nanoparticles (ECG‐AuNPs and EGCG‐AuNPs). The extent of inhibition was confirmed using an agarose gel‐based assay followed by fluorescence titration studies that indicated a hundred fold stronger binding of polyphenol‐capped gold nanoparticles (GTP‐AuNPs) compared to the bare polyphenols. Interestingly, we found a change in the mode of inhibition from a noncompetitive type to a competitive mode of inhibition in case of the GTP‐AuNPs, which is in agreement with the 'n' values obtained from the fluorescence quenching studies. The effect on angiogenesis has also been assessed by the chorioallantoic membrane (CAM) assay. We find an increase in the inhibition potency of GTP‐AuNPs that could find applications in the development of anti‐angiogenic compounds. [ABSTRACT FROM AUTHOR]

The chemopreventive activity of green tea (GT) is limited by the low bioavailability and extensive methylation of GT polyphenols (GTPs) in vivo. We determined whether a methylation inhibitor quercetin (Q) will enhance the chemoprevention of prostate cancer in vivo. Androgen-sensitive LAPC-4 prostate cancer cells were injected subcutaneously into severe combined immunodeficiency (SCID) mice one week before the intervention. The concentration of GTPs in brewed tea administered as drinking water was 0.07% and Q was supplemented in diet at 0.2% or 0.4%. After 6-weeks of intervention tumor growth was inhibited by 3% (0.2% Q), 15% (0.4% Q), 21% (GT), 28% (GT+0.2% Q) and 45% (GT+0.4% Q) compared to control. The concentration of non-methylated GTPs was significantly increased in tumor tissue with GT+0.4% Q treatment compared to GT alone, and was associated with a decreased protein expression of catechol-O-methyltransferase and multidrug resistance-associated protein (MRP)-1. The combination treatment was also associated with a significant increase in the inhibition of proliferation, androgen receptor and phosphatidylinositol 3-kinase/Akt signaling, and stimulation of apoptosis. The combined effect of GT+0.4% Q on tumor inhibition was further confirmed in another experiment where the intervention started prior to tumor inoculation. These results provide a novel regimen by combining GT and Q to improve chemoprevention in a non-toxic manner and warrant future studies in humans.

Dietary fiber and polyphenols have been shown to possess antiobesity properties. However, their combined effects need further investigation. This study investigated the individual and combined effects of arabinoxylan oligosaccharides (AXOS) from rice bran and green tea polyphenols (GTP) in high-fat diet-induced obese mice. We found that the combination of AXOS and GTP (A + G) significantly reduced overall fat mass and improved lipid profiles, although the effects were not synergistic. AXOS and GTP regulated lipid metabolism in different tissues and exhibited counteractive effects on gut microbiota. AXOS decreased α diversity and promoted Bifidobacterium , with GTP counteracting these effects. In vitro fermentation confirmed that GTP counteracted AXOS-induced microbiota changes in a dose-dependent manner. This study highlights the potential of tailored combinations of dietary fiber and polyphenols to treat obesity while considering their complex microbial interplay.

Green tea, derived from Camellia sinensis, contains polyphenolic active compounds that exhibit diverse pharmacological effects including anticancer, anti-inflammatory, antioxidant, and immunomodulatory properties. Employing various concentrations of green tea polyphenols (GTPs; 0, 100, 200, 300, 400, 500 μg∕mL), human normal lung epithelial cells (BEAS-2B) and non-small cell lung cancer (NSCLC) cells (A549) underwent treatment. The cell viability was assessed using the cell counting kit-8 (CCK-8) assay, proliferation was examined through the colony formation assay, apoptosis was monitored via flow cytometry, cell migration, and epithelial-mesenchymal transition (EMT)-associated proteins (E-cadherin, N-cadherin) were determined by Western blot. A549 cells were subjected to Cisplatin (0, 0.5, 1, 1.5 μM) and X-ray irradiation (0, 2, 4, 6 Gy) for treatment to probe the influence of GTPs on A549 cells in response to chemoradiotherapy. The functioning mechanism of GTPs in the context of NSCLC was validated using lithium chloride (LiCl) [a glycogen synthase kinase-3 beta (GSK-3β) inhibitor], which activates the Wnt∕β-catenin pathway. GTPs suppressed NSCLC cell viability in a concentration-dependent pattern, with a half-maximal inhibitory concentration (IC50) of 362.5 μg∕mL, while showing little impact on BEAS-2B cells' viability (at concentrations not exceeding 500 μg∕mL). Treatment with GTPs dampened colony formation of NSCLC cells, while promoting apoptosis. LiCl treatment vigorously attenuated the inhibitory impact of GTPs on the malignant phenotype of NSCLC cells. Mechanistic studies suggested that GTPs strengthened GSK-3β stability, thereby impeding the Wnt∕β-catenin pathway. Tea polyphenols (TPs) in conjunction with concurrent radiochemotherapy (CRCT) enhance the stability of GSK-3β and dampen the Wnt∕β-catenin pathway, hence exerting anticancer effects in NSCLC., Competing Interests: The authors declare that they have no conflict of interests.

This study focused on the modulatory effect of green tea polyphenols (GTP) on human intestinal microbiota, and its underlying anti-obesity mechanisms. GTP was prepared from Chinese green tea by column chromatography, and then the influence of GTP on intestinal microbiome was analyzed with a human flora-associated (HFA) high fat diet-induced obesity mice model by metagenomics. GTP ameliorated the obesity-induced gut dysbiosis; in addition, a significant decrease was observed in Firmicutes/Bacteroidetes after GTP treatment. Moreover, KEGG pathways of ATP-binding cassette (ABC) transporters, two-component system and biosynthesis of amino acids enriched the most differentially expressed genes after GTP intervention for 8 weeks. Our results may have important implications for the use of GTP as a functional food component with potential therapeutic utility against high fat diet induced obesity, and prebiotic-like activity by modulating intestinal microbiota and affecting certain metabolic pathways, contributing to the improvement of host health.

Background: Aberrations in the regulation of cell proliferation perturb cellular homeostasis and lead to malignancies in which dysregulation of the cell cycle and suppressed apoptosis are 2 common phenomena. Combinatorial nutritional approaches could be efficacious in ameliorating these aberrations.Objectives: We sought to investigate the effect of dietary broccoli sprouts (BSp) and green tea polyphenol (GTP) administration on cell cycle progression and apoptosis in mammary tumors.Methods: Forty female HER2/neu transgenic mice were randomly divided into 4 groups and treated with control, 26% BSp (wt:wt) in food, 0.5% GTPs (wt:vol) in drinking water, or combined BSp and GTPs from dams' conception until their pups were killed at 29 wk of age. Pups' tumor growth was monitored weekly for 27 wk. Tumor cell cycle- and apoptosis-related protein expression was measured. Data were analyzed with 2-factor or 3-factor (repeated-measures) ANOVA.Results: Compared with the control group, BSp and/or GTPs decreased tumor incidence (P < 0.05) and combined BSp and GTPs synergistically [combination index (CIn) < 1] reduced tumor volume over time (P-time < 0.01). BSp and/or GTPs upregulated the expression of phosphatase and tension homolog, P16, and P53 (P < 0.05) and downregulated myelocytomatosis oncogene, Bmi1 polycomb ring finger oncogene, and telomerase reverse transcriptase (P < 0.05) compared with the control group. Combined BSp and GTPs synergistically (CIn < 1) downregulated the expression of cyclin B1, D1, and E1 and cyclin-dependent kinase 1, 2, and 4 (P < 0.05) compared with the control group. Moreover, combined BSp and GTPs induced apoptosis by regulating Bcl-2-associated X protein and B-cell lymphoma 2 (P < 0.05). BSp and/or GTPs also reduced the expression of DNA methyltransferase 1, 3A, and 3B and histone deacetylase 1 compared with the control group (P < 0.05).Conclusions: Collectively, lifelong BSp and GTP administration can prevent estrogen receptor-negative mammary tumorigenesis through cell cycle arrest and inducing apoptosis in HER2/neu mice. [ABSTRACT FROM AUTHOR]

It was found that green tea (GT) and its catechins, can decrease the malignant behavior of several tumors and inhibit metastasis and lower the recurrence rate. The purpose of this paper was to review the literature about the different anticancer activity of GT with particular focusing on the molecular mechanisms and molecular targets underlying this activity. The mechanisms underlying the anti-cancer activity are the enhancement of apoptosis and inhibition of the proliferation of malignant cells, mutagenesis and genotoxicity inhibition, decrease the expression levels of VEGF, inhibition of NK-κB and AP-1 activity, inhibiting nitric oxide production, inhibition of TNF-α, COX-2, MMP2, MMP-9 expression and receptor tyrosine kinases pathways, increase sensitivity of anticancer agents, antioxidant/induction of oxidative stress, immunomodulation against malignancy, and anti-metabolic syndrome effects. Understanding of all the detailed pathological roles of green tea against tumors is important to evaluate the preventive measures and the treatment of different types of malignancy. [ABSTRACT FROM AUTHOR]

Nanodrug delivery systems have been widely researched to achieve efficient antitumor drug delivery. However, the controlled drug delivery at tumor cells remains the main challenge for antitumor therapy. Herein, a pH and reduction-responsive nanocarrier based on green tea polyphenols was employed as a smart excipient for chemotherapy drug delivery. Paclitaxel, as a chemotherapy drug, was loaded in the nanocarrier, noted as green tea polyphenol/paclitaxel. The green tea polyphenol/paclitaxel kept constant diameter at physiological condition (i.e. pH 7.4), while gradually enlarged at acid environment (pH = 5.5) and the reductive environment. The in vitro paclitaxel release results indicated that the release of paclitaxel from the green tea polyphenol/paclitaxel at pH 7.4 was slow, whereas obviously accelerated at the acid environment (pH = 5.5) and the reductive environment. The in vitro antitumor assay showed more efficient tumor cells inhibition of green tea polyphenol/paclitaxel than free paclitaxel. Meanwhile, due to the proper size (∼100 nm), green tea polyphenol/paclitaxel could effectively accumulate at tumor sites. In the in vivo mice bearing A549 xenograft mouse models, green tea polyphenol/paclitaxel exhibited satisfactory antitumor effect and depressed system toxicity when compared with free paclitaxel, owing to the enhanced paclitaxel accumulation and controlled paclitaxel release in the tumor cells. With simple compositions and satisfactory antitumor effects, this green tea polyphenol-based nanocarrier can be a promising nanodrug delivery system for the therapy of cancers. [ABSTRACT FROM AUTHOR]

Abstract Background We have previously demonstrated that a mixture of Curcuminoids extract, hydrolyzed COllagen and green Tea extract (CCOT) inhibited inflammatory and catabolic mediator’s synthesis by bovine and human chondrocytes. A randomly allocated, double-blind, prospective, placebo-controlled study was performed to evaluate the efficacy of a diet containing this CCOT mixture on dogs with naturally occurring osteoarthritis (OA). Therefore, 42 owner’s dogs with OA were randomly assigned to receive for 3 months an experimental diet (control) or the same diet supplemented with CCOT. Results Ground reaction forces did not show statistical differences between groups. After 3 months of feeding, there was a significant reduction of pain at manipulation in the CCOT group, but not in the control group. The evolution for pain at manipulation depended on the diet. The three other parameters evaluated by veterinary subjective assessment (lameness, pain at palpation and joint mobility) did not show statistical differences. Concerning owner subjective assessment, pain severity score worsened in the control group but remained stable in CCOT group. The evolution for pain severity depended on the diet. No statistical difference was found for pain interference, except for the ability to rise to standing from lying down, which was significantly improved in the CCOT compared to the control group. Serum OA biomarkers did not show statistical differences. Conclusions Objective variables measured, such as ground reaction forces and OA biomarkers, did not show statistical differences. However, indicators of pain appeared reduced in dogs receiving CCOT mixture for 3 months. The difference of evolution between groups suggests that a greater number of dogs may be necessary to reach a stronger effect on other parameters.

Background: Many cancer studies have intensely focused on the role of diet, among other factors involved in cancer establishment. The positive effect of green tea polyphenols (GTP) on controlling breast cancer cells has been reported in several studies. Cancer stem cell-like cells (CSC-LCs) possessing self-renewal, metastatic, and drug-resistant capacities are considered prominent therapeutic targets. In many tumors, inducible nitric oxide synthase (iNOS) expression levels are high; however, they have a dual effect on breast cancer pathogenesis., Objective: This study aimed to investigate the cytotoxicity of the iNOS agonist (Sildenafil) and antagonist (LNAME), both alone and in combination with GTP, on MDA-MB-231, CD44+/CD24- CSC-LCs, and their parental cells (MCF-7)., Methods: The cell viability assay has been studied using the MTT assay. To analyze drug-drug combinations, CompuSyn and Combenefit software were used. The cytotoxicity mechanism was determined using flow cytometric analysis., Results: L-NAME and GTP showed a synergistic effect on MDA-MB-231 and CSC-LCs. Such an effect was not observed on MCF-7. Sildenafil and GTP, on the other hand, showed synergistic cytotoxicity in all the cells mentioned above. Flow cytometric tests resulted in more than 70% apoptosis in MDA-MB-231 and MCF-7. Also, sub-G1 arrest among MCF-7 cells and a considerable decrease in ROS production by MDA-MB-231 cells following treatment with Sildenafil and GTP were observed., Conclusion: Sildenafil, in combination with flavonoids, may be considered a novel strategy for cancer treatment., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Green tea and its bioactive components, especially polyphenols, possess many health-promoting and disease-preventing benefits, especially anti-inflammatory, antioxidant, anticancer, and metabolic modulation effects with multi-target modes of action. However, the effect of tea polyphenols on immune function has not been well studied. Moreover, the underlying cellular and molecular mechanisms mediating immunoregulation are not well understood. This review summarizes the recent studies on the immune-potentiating effects and corresponding mechanisms of tea polyphenols, especially the main components of (–)-epigallocatechin-3-gallate (EGCG) and (–)-epicatechin-3-gallate (ECG). In addition, the benefits towards immune-related diseases, such as autoimmune diseases, cutaneous-related immune diseases, and obesity-related immune diseases, have been discussed.

Drug release kinetics plays an important role in determining the mechanism of drug release, which in turn helps in formulating controlled/sustained release formulations. In our study, different concentrations of green tea polyphenols (GTP) were encapsulated into casein nanoparticles which showed a maximum encapsulation efficiency (76.9%) at a GTP concentration of 5 mg/mL. The casein nanoparticles were characterized through particle size analysis, zeta potential, AFM, and HR SEM, followed by molecular docking studies, which confirmed the binding of GTP to casein nanoparticles. In-vitro release studies carried out at different temperatures and pH showed no significant difference in the release pattern, but the release was prolonged even up to 48 h. On varying pH of the release medium, an increase in the percentage of release was observed as the pH shifted from acidic to basic. All release data showed good correlation with Zero order kinetics, an ideal model for release of drugs from nanoparticulate sustained release formulations, with anomalous mode of drug transport. Antioxidant activity of the released GTP determined through DPPH assay showed potent antioxidant effect of GTP even after 48 h of its release. Our data indicated that casein nanoparticles could be used as a potent vehicle for the delivery of GTP for achieving a sustained release. [ABSTRACT FROM AUTHOR]

DGKθ protein expression levels are closely related to the development of diseases including diabetes, cancer, and neuronal disease. To investigate the transcriptional regulation of the DGKθ gene, we used CRISPR/Cas9 to generate a DGKθ endogenous promoter luciferase reporter HepG2 cell line, in which the endogenous DGKθ promoter controls the expression of the luciferase reporter gene. To test the cell line, FXR, the transcription factor for upregulating the expression of DGKθ gene, was used to validate the cell line. Furthermore, the reported agonists for the expression of DGKθ, cAMP and GW4064, the known inhibitor for DGKθ enzyme activity, R59949, and a potential regulator for DGKθ enzyme expression, EGCG (the major catechin in green tea), were applied to the reporter cell line. The results indicated that these reagents could significantly regulate the expression of reporter luciferase. Finally, four transcription factors (E2F1, c-Myc, USF1, and Bmal1) potentially binding to the DGKθ gene's upstream promoter region were tested. DGKθ expression was upregulated by c-Myc and downregulated by E2F1, which was also confirmed in wild-type HepG2 cells. We found that the cell line's luciferase activity was directly correlated with DGKθ endogenous promoter activity, suggesting that it is liable and sensitive for studying DGKθ transcriptional regulation. The study provides a useful tool for high-throughput drug screening for the treatment of DGKθ-involved diseases. [ABSTRACT FROM AUTHOR]

Objective: this review aimed to investigate the effects of green tea polyphenols (GTP) in Ulcerative colitis and Crohn´s Disease.Materials and Methods: The databases used were MEDLINE-and EMBASE (October 2009 to September 2018). Studies that reported the use of green tea and its effects on IBD were included.Results: Ten articles were included in this review.Discussion: GTP play a role in reducing TNF-α, Interleukin 1β (IL-1β), IL-6, IL-8, and 17; downregulate cyclooxygenase-mediated I kappa B kinase and transcription of NFκB. They regulate the pathways mediated by the Nuclear erythroid 2-related factor 2, mitogen-activated protein kinases, and signal transducer and the activator of transcription 1/3, and also minimize the lipid peroxidation. Furthermore, GTP can stimulate antioxidant enzymes. These actions reduce inflammatory and oxidant patterns in IBD resulting in improvement of the disease scores.Conclusions: We suggest that professionals and researchers take into account the use of GTP in further researches and in clinical practice in order to verify the real effects in humans. [ABSTRACT FROM AUTHOR]

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Among polyphenol compounds, the flavan-3-ol structure, which is the basic unit of green tea catechins and the galloyl groups contained in green tea catechins are known to exhibit various functions. In this paper, we discuss how to concentrate highly functional polyphenol compounds by exploiting the interaction between gelatin and the catechol structures. First, we confirmed the interaction between heat-stabilized gelatin and flavan-3-ol derivatives, including synthesized compounds. When green tea leaf extract containing a large amount of flavan-3-ol derivatives was incubated with gelatin, most of the polyphenol compounds it contained were adsorbed. Because the compounds adsorbed on gelatin could not be eluted, DPPH radical and ABTS radical scavenging activity tests were conducted using the as-prepared gelatin–polyphenol complex. Radical scavenging activity was observed when the compounds were adsorbed on gelatin and heating at 90 °C for 5 min did not have a significant effect on their activity. These results suggest that functional polyphenols can be efficiently concentrated using heat-stabilized gelatin and retain their functionality while adsorbed.

Epigallocatechin gallate (EGCG) is a polyphenol present in green tea (Camellia sinensis), which has revealed anti-cancer effects toward a variety of cancer cells in vitro and protective potential against neurodegenerative diseases such as Alzheimer's and Parkinson's. Unfortunately, EGCG presents disappointing bioavailability after oral administration, primarily due to its chemical instability and poor absorption. Due to these limitations, EGCG is currently not used in medication, but only as a dietary supplement in the form of green tea extract. Therefore, it needs further modifications before being considered suitable for extensive medical applications. In this article, we review the scientific literature about EGCG derivatives focusing on their biological properties and potential medical applications. The most common chemical modifications of epigallocatechin gallate rely on introducing fatty acid chains or sugar molecules to its chemical structure to modify solubility. Another frequently employed procedure is based on blocking EGCG's hydroxyl groups with various substituents. Novel derivatives reveal interesting properties, of which, antioxidant, anti-inflammatory, antitumor and antimicrobial, are especially important. It is worth noting that the most promising EGCG derivatives present higher stability and activity than base EGCG. [Display omitted] • EGCG is a promising compound with multidirectional biological action. • EGCG derivatives show improved pharmacokinetic parameters. • EGCG derivatives reveal superior biological effects than EGCG. [ABSTRACT FROM AUTHOR]

Heretofore, there are no effective therapeutic interventions for food allergies induced by β-conglycinin, an major allergen in soybean. The objective of this study was to explore the alleviating effect and underlying mechanism of green tea polyphenols (GTPs) on β-conglycinin-induced anaphylaxis. Twenty-one-day-old weaned BN rats were sensitized by gavage of β-conglycin and then given drinking water containing 1% GTPs. The results showed that β-conglcyinin sensitized rats had increased serum IgE levels and IL-4 level in spleen cell culture supernatant compared with the control group. However, total IgE, β-conglycin-specific IgE and IL-4 levels were significantly decreased by GTPs, suggesting that it weakened Th2-type immune response and restored cytokine homeostasis. The impact of GTPs on gut microbiota mainly focused on the changes in specific microbes, characterized by a significant increase of Bacteroides and other beneficial bacteria, which would contribute to the recovery of gastrointestinal allergies. This study is the first to demonstrate that GTPs, as good immunomodulator, played an important role in alleviating soybean protein allergy, which were associated with the alterations in gut microbiota. These results contribute to the development and application of green tea and provided an effective nutritional therapy strategy for the prevention and treatment of allergic diseases caused by soybean allergens. [Display omitted] • β-conglycinin induced a Th2-type hypersensitivity in BN rat model. • GTPs weakened Th2-type immune response and restored cytokine homeostasis. • The impact of GTPs on gut microbiota focused on the changes of specific microbes. • Specific microbes contributed to the recovery of gastrointestinal allergy. [ABSTRACT FROM AUTHOR]

The safety of concentrated food complements intake is a major health concern. It has been well established that green tea polyphenols (GTPs) consumption promotes healthy effects. However, the ingestion of large amounts of GTPs is a matter of controversy due to reported adverse effects. We underwent a preliminary exploration of the effects of the oral administration of a standardized concentrated GTPs preparation on mice which suffered from reversible intestinal derangement promoted by sublethal amounts of the antiribosomal lectin ebulin f from dwarf elder (Sambucus ebulus L.). Neither independent oral administration of 30 mg/kg body weight Polyphenon 60 nor intraperitoneal administration of 2.5 mg/kg body weight ebulin f triggered lethal toxicity. In contrast, the simultaneous administration of these same doses of both Polyphenon 60 and ebulin f triggered an important and unexpected synergistic toxic action featured by the biphasic reduction of weight, which continued after eight days, reaching a reduction of 40%. Lethality appeared 2 days after the onset of the combined treatment and reached more than 50% after 10 days.

In order to investigate the protective effect of green tea polyphenols (GTP) on benzo[a]pyrene (BaP)-induced reproductive and trans-generational toxicity, Japanese Medaka was injected intraperitoneally with BaP alone and co-injected with both BaP and GTP of different concentrations, respectively. Exposure to BaP alone significantly suppressed fecundity, fertilization success, and egg diameter/protein content and markedly induced deformation ratio in F1 generation. However, GTP could help recover reproductive functions, egg quality suppressed by BaP and reduced deformation ratio. VTG-1, a molecular marker of reproductive toxicity, was significantly down-regulated in females exposed to BaP, but a dose-dependent increase was observed in co-exposed groups. Up-regulation of GSH-Px, dose-dependent decrease of CYP1A1, and the GST expression inhibited by BaP was recovered and even markedly up-regulated in the co-exposure groups. These findings show promising protective effects of GTP against BaP-induced reproductive and trans-generational toxicity.

Antigen detection during Western blotting commonly utilizes a horseradish peroxidase-coupled secondary antibody and enhanced chemiluminescent substrate. We utilized this technique to examine the impact of green tea-derived polyphenols on the binding of egg white protein-specific IgE antibodies from allergic human plasma to their cognate antigens. Our experiments unexpectedly showed that green tea-derived polyphenols, when stably complexed with egg white proteins, caused “ghost” band formation in the presence of horseradish peroxide. This study suggests that caution should be taken when evaluating polyphenol-bound proteins by enhanced chemiluminescence Western blotting using horseradish peroxidase and demonstrates that protein-bound polyphenols can be a source of “ghost” band artifacts on Western blots.

Antigen detection during Western blotting commonly utilizes a horseradish peroxidase-coupled secondary antibody and enhanced chemiluminescent substrate. We utilized this technique to examine the impact of green tea-derived polyphenols on the binding of egg white protein-specific IgE antibodies from allergic human plasma to their cognate antigens. Our experiments unexpectedly showed that green tea-derived polyphenols, when stably complexed with egg white proteins, caused hyperactivation of horseradish peroxidase resulting in the appearance of white “ghost” bands. This study suggests that caution should be taken when evaluating polyphenol-bound proteins by enhanced chemiluminescence Western blotting using horseradish peroxidase and demonstrates that protein-bound polyphenols can be a source of “ghost” band artifacts on Western blots.