Beneficial effects of green tea: a literature review

Green Tea Mitigates the Hallmarks of Aging and Age-Related Multisystem Deterioration

Aging is characterized by progressive multisystem deterioration driven by molecular and cellular mechanisms encapsulated in the twelve hallmarks of aging. Green tea (GT), derived from Camellia sinensis, has garnered significant scientific interest due to its rich polyphenolic composition, particularly epigallocatechin-3-gallate, and its pleiotropic health benefits. In this narrative review, we explored the multifaceted mechanisms through which GT may mitigate the aging hallmarks. Evidence from in vitro, animal, and human studies has shown that GT polyphenols can enhance DNA repair pathways, preserve telomere length, modulate epigenetic aging markers, improve proteostasis and autophagic flux, regulate nutrient-sensing networks, and rejuvenate mitochondrial function. Additionally, GT exhibits anti-inflammatory properties and may restore a physiological gut microbiota composition. Beyond molecular and cellular effects, GT consumption in humans has been associated with improved cognitive function, cardiovascular health, muscle preservation, and metabolic regulation in aging populations. Collectively, these findings highlight GT's potential as a naturally occurring geroscience intervention capable of addressing the interconnected network of aging processes more comprehensively than single-target pharmaceuticals. Future research should focus on optimizing dosing regimens, exploring synergies with other anti-aging strategies, and investigating personalized responses to GT interventions.

Epigallocatechin Gallate Promotes Cuproptosis via the MTF1/ATP7B Axis in Hepatocellular Carcinoma

BACKGROUND

Cuproptosis is a form of copper-dependent non-apoptotic cell death. Cancer cells that prefer to use aerobic glycolysis for energy generation are commonly insensitive to cuproptosis, which hinders its application for cancer treatment. Epigallocatechin gallate (EGCG) possesses diverse pharmacological activities. However, the association between EGCG and cuproptosis has not been studied.

METHODS

The cell viability, proliferation, and cuproptosis-related protein levels were detected to investigate whether EGCG enhances the sensitivity of HCC cells to cuproptosis. The intracellular copper level, related copper metabolism proteins, and gene expression were detected to explore the mechanisms. In addition, a nude mouse xenograft model was established to determine the effects of EGCG on cuproptosis in tumor tissues.

RESULTS

The combination of EGCG and copper ionophores significantly enhanced the mortality of HCC cells and heightened the sensitivity of HCC cells to cuproptosis. There was a notable reduction in the expression of copper export protein copper-transporting P-type ATPase (ATP7B). EGCG effectively suppressed metal regulatory transcription factor (MTF1) expression and subsequently hindered the transcriptional regulation of ATP7B. EGCG also facilitated the intratumoral accumulation of copper and augmented susceptibility to cuproptosis in vivo.

CONCLUSIONS

EGCG can increase the sensitivity of hepatocellular carcinoma cells to cuproptosis by promoting intracellular copper accumulation through the MTF1/ATP7B axis.

Pectin as the carrier for the spray drying of green tea extracts: Tailoring microencapsulation to obtain a prospective nutraceutical

In this study, microencapsulated green tea (GT) extracts, as prospective nutraceuticals, were obtained using spray drying with pectin in different pectin-to-extract (P:E) ratios. Pectin was selected as wall material based on its previously reported superiority to encapsulate phenols, low cost/sustainability of production and intrinsic hypoglycemic and antioxidant potential. A significant degradation (13.74 %) of epigallocatechin was observed in powder without pectin, in contrast to pectin-loaded samples, suggesting its role in chemical stability enhancement of stated compound. FTIR and DSC indicated GT extract bioactives to remain stable during drying. Addition of pectin significantly increased encapsulation efficacy (EE) of epigallocatechin-3-gallate (up to 8.94 %), epicatechin-3-gallate (up to 7.68 %) and caffeine (up to 12.39 %) compared to pectin-free sample. Significant EE enhancement for epigallocatechin-3-gallate was observed until the P:E ratio of 1:1 compared to pectin-free sample, while further increase of pectin share did not lead to a comparative increase in EE. Similar trend was observed for powder flowability, probably due to excess of pectin in the highest P:E ratio (2:1), preventing proper droplets formation, which was also confirmed by SEM. Sample with P:E ratio of 1:1 revealed the slowest release of bioactives, which may be important for facilitating potential GT therapeutic usage. Stated microencapsulate further revealed satisfactory antioxidant (IC50 of 23.70 μg/ml vs. 4.45 μg/ml for ascorbic acid) and hypoglycemic activities (IC50 of 39.48 μg/ml vs. 156.64 μg/ml for acarbose). These findings represent the basis for further experiments regarding usage of the developed GT microencapsulate as nutraceutical applicable in diabetes-related impairments.

Green Tea: Current Knowledge and Issues

Green tea possesses antioxidant, anti-inflammatory, anticancer, and antimicrobial activities, reduces body weight, and slows down aging. These effects are primarily attributed to catechins contained in green tea leaves, particularly epigallocatechin-3-gallate. However, in humans, the realization of green tea's beneficial effects is limited. In order to summarize and critically analyze the available scientific information about green tea's health benefits and issues related to its use, we conducted an in-depth literature review in scientific databases. A number of in vitro studies reported that green tea catechins modulate various signaling pathways in cells, which is thought to underlie their beneficial effects. However, data on the effects of catechins in humans are scarce, which is partly due to their low stability and oral bioavailability. Furthermore, catechins may also participate in pharmacokinetic interactions when co-administered with certain drugs such as anticancer agents, drugs for cardiovascular diseases, immunosuppressors, etc. As a result, adverse drug reactions or therapy failure may occur. In conclusion, over the years, various approaches have been investigated to optimize catechin intake and to achieve beneficial effects in humans, but to date, the use of catechins for prophylaxis or disease treatment remains limited. Therefore, future studies regarding the possibilities of catechins administration are needed.

Green Tea Components: In Vitro and In Vivo Evidence for Their Anticancer Potential in Colon Cancer

Green tea consumption has been implicated in various biological activities, with particular emphasis on its anticancer properties. The antineoplastic effects of green tea are primarily attributed to its rich polyphenol content, among which, epigallocatechin-3-gallate (EGCG) is recognized as the most bioactive and potent catechin, responsible for the majority of its anticancer activity. This review provides a detailed examination of the in vitro and in vivo effects of green tea components, focusing on their potential therapeutic implications in colorectal cancer. The molecular mechanisms of action and bioactive constituents of green tea are systematically discussed, alongside an evaluation of experimental evidence supporting their efficacy. Furthermore, insights into the relationship between green tea dietary intake and colorectal cancer risk are analyzed, with a particular emphasis on clinical data and findings from meta-analyses involving patients diagnosed with colon cancer. The aggregated evidence underscores the necessity for well-designed randomized controlled trials and longitudinal cohort studies to substantiate the role of green tea as a chemopreventive agent. Additionally, future investigations should prioritize determining the optimal dosages, the appropriate durations of consumption, and the potential modulatory effects of dietary or lifestyle factors on green tea's anticancer efficacy.

Exploring the Therapeutic Potential of Green Tea (Camellia sinensis L.) in Anti-Aging: A Comprehensive Review of Mechanisms and Findings

Green tea (GT) is rich in phyto-active compounds such as epigallocatechin gallate (EGCG), epigallocatechin (EGC), epicatechin gallate (ECG), epicatechin (EC), catechin, and tannic acid, which exhibit synergistic effects when combined. Preclinical studies demonstrate that GT and its compounds can reduce reactive oxygen species (ROS), enhance antioxidant capacity, and alleviate aging-related issues such as memory impairments, cognitive decline, and shortened lifespan. Clinical trials corroborate the efficacy of topical GT formulations in improving skin tone, texture, and elasticity and reducing wrinkles. The present manuscript summarizes the recent update on the anti-aging potential of GT and its possible mechanisms. The literature survey suggests that GT consumption is linked to improved cognition, reduced depression levels, and activation of pathways in model organisms like C. elegans. Additionally, tea polyphenols enhance fibroblast mitophagy, boost hippocampal synaptic plasticity in rodents, and mitigate age-related cognitive decline. Moreover, EGCG exhibits anti-aging properties by reducing TNF-induced MMP-1 expression, suppressing ERK signaling, and inhibiting MEK and Src phosphorylation in human dermal fibroblasts. In the context of skin permeation and deposition, optimized transfersomal formulation (TF) incorporating EGCG and hyaluronic acid (HA) demonstrates significantly increased skin permeation and deposition of EGCG compared to plain EGCG. Furthermore, EGCG protects cardiomyocytes via the PPARγ pathway and combats age-related muscle loss through miRNA-486-5p regulation, AKT activation, and FoxO1a-mediated expression of MuRF1 and Atrogin-1. In conclusion, the regular consumption of GT holds promise for promoting physical and mental health, delaying brain and skin aging, and improving overall health by enhancing total antioxidant capacity.

Cholesterol Absorption Inhibition by Some Nutraceuticals

Hyperlipidemia, characterized by elevated levels of lipids in the blood, represents a major risk factor for cardiovascular diseases, a leading cause of morbidity and mortality worldwide. Conventional pharmacological interventions have been effective in managing hyperlipidemia, but concerns about side effects and long-term use have prompted interest in alternative approaches, particularly the use of nutraceuticals. This comprehensive review aims to summarize and critically evaluate the current body of knowledge surrounding the role of nutraceuticals in the management of hyperlipidemia. We provide an overview of the different classes of nutraceuticals, including plant sterols, omega-3 fatty acids, soluble fiber, antioxidants, and various herbal extracts, which have been investigated for their lipid-lowering properties. The mechanisms of action of these nutraceuticals are discussed, highlighting their ability to modulate lipid metabolism, reduce oxidative stress, and promote cardiovascular health. Furthermore, we review the results of clinical trials and epidemiological studies that have assessed the efficacy of nutraceutical interventions in lowering cholesterol levels, improving lipid profiles, and reducing the risk of cardiovascular events. In addition to their lipid-lowering effects, we examine the safety profile, dosage recommendations, and potential interactions of nutraceuticals with conventional lipid-lowering medications. We also address the importance of patient adherence to dietary and lifestyle modifications in conjunction with nutraceutical supplementation. While nutraceuticals offer a promising avenue for managing hyperlipidemia, we emphasize the need for further research to establish evidence-based guidelines for their use in clinical practice. Challenges related to standardization, quality control, and regulatory considerations are also discussed. In conclusion, this comprehensive review provides valuable insights into the potential of nutraceuticals as adjunctive or alternative therapies for managing hyperlipidemia. While further research is needed, the accumulating evidence suggests that nutraceuticals can play a valuable role in promoting cardiovascular health and reducing the burden of hyperlipidemia-related diseases.

Structure-based clustering and mutagenesis of bacterial tannases reveals the importance and diversity of active site-capping domains

Tannins are critical plant defense metabolites, enriched in bark and leaves, that protect against microorganisms and insects by binding to and precipitating proteins. Hydrolyzable tannins contain ester bonds which can be cleaved by tannases-serine hydrolases containing so-called "cap" domains covering their active sites. However, comprehensive insights into the biochemical properties and structural diversity of tannases are limited, especially regarding their cap domains. We here present a code pipeline for structure prediction-based hierarchical clustering to categorize the whole family of bacterial tannases, and have used it to discover new types of cap domains and other structural insertions among these enzymes. Subsequently, we used two recently identified tannases from the gut/soil bacterium Clostridium butyricum as model systems to explore the biochemical and structural properties of the cap domains of tannases. We demonstrate using molecular dynamics and mutagenesis that the cap domain covering the active site plays a major role in enzyme substrate preference, inhibition, and activity-despite not directly interacting with smaller substrates. The present work provides deeper knowledge into the mechanism, structural dynamics, and diversity of tannases. The structure-based clustering approach presents a new way of classifying any other enzyme family, and will be of relevance for enzyme types where activity is influenced by variable loop or insert regions appended to a core protein fold.

Novel Epigallocatechin Gallate (EGCG) Analogs with Improved Biochemical Properties for Targeting Extracellular and Intracellular Staphylococcus aureus

Staphylococcus aureus is a leading cause of bloodstream infection (SAB), with up to 30% mortality. Despite treatment with standard antibiotics, one in three patients develops a persistent infection, which portends a five-fold increase in the risk of death. Persistent SAB has been attributed in part to the inability of antistaphylococcal antibiotics to eradicate intracellular S. aureus surviving inside macrophages. (-)- Epigallocatechin gallate (EGCG) is a catechin found in green tea that has been widely studied for its broad biological activities, ranging from anticancer to antibacterial activity. However, EGCG is greatly limited by its poor drug-like properties in terms of stability, membrane permeability, and bioavailability. In this study, we established through a series of in vitro experiments that structural modifications of EGCG enhanced drug-like properties while maintaining or improving its antistaphylococcal activity. Our lead EGCG analogs (MCC-1 and MCC-2) showed improved biochemical properties along with increased potency against extracellular S. aureus and restored susceptibility of β-lactam agents to methicillin-resistant S. aureus (MRSA). Importantly, the lead analogs but not EGCG potentiated macrophage- and antibiotic-mediated clearance of intracellular bacteria. Overall, EGCG analogs showed promise for further development as adjunctive therapy candidates for the treatment of SAB.

Epigallocatechin gallate-rich fraction alleviates histamine-induced neurotoxicity in rats via inactivating caspase-3/JNK signaling pathways

Ingestion of prominent levels of histamine (HIS) leads to dangerous effects on biological systems. The most frequent and active catechin in green tea is epigallocatechin gallate which has strong antioxidant properties. Our research intended to investigate the possible neuroprotective effect of epigallocatechin gallate-rich fraction (EGCGR) against HIS-inducing neurotoxicity. Six groups of male rats (n = 5) were used as follows: (1) Distilled water, (2&3) EGCGR (100-200 mg/kg BWT/day, respectively), (4) HIS (1750 mg/kg BWT/week, (5&6) HIS + EGCGR. Administration of HIS for 14 days induced severe neurobehavioral changes including depression, incoordination, and loss of spatial memory. Extensive neuronal degeneration with diffuse gliosis was the prominent histopathological lesion observed and confirmed by strong immunostaining of casp-3, Cox-2, and GFAP. Additionally, the HIS group showed a significantly higher MDA level with lower CAT and GSH activity than the control group. Moreover, HIS promoted apoptosis, which is indicated by increasing JNK, and Bax and decreasing Bcl-2 gene expressions. Otherwise, the oral intake of EGCGR with HIS improved all neurotoxicological parameters induced by HIS. We concluded that HIS could cause neurotoxicity via an upset of the equilibrium between oxidants and antioxidants which trigger apoptosis through modulation of JNK signaling pathway. Furthermore, EGCGR has either direct or indirect antihistaminic effects.

Anti-atherogenic role of green tea (Camellia sinensis) in South Indian smokers

ETHNOPHARMACOLOGICAL RELEVANCE

Green tea (Camellia sinensis) is a popular beverage consumed all over the world due to its health benefits. Many of these beneficial effects of green tea are attributed to polyphenols, particularly catechins.

AIM OF THE STUDY

The present study focuses on underlying anti-platelet aggregation, anti-thrombotic, and anti-lipidemic molecular mechanisms of green tea in South Indian smokers.

MATERIALS AND METHODS

We selected 120 South Indian male volunteers for this study to collect the blood and categorised them into four groups; control group individuals (Controls), smokers, healthy control individuals consuming green tea, and smokers consuming green tea. Smokers group subjects have been smoking an average 16-18 cigarettes per day for the last 7 years or more. The subjects (green tea consumed groups) consumed 100 mL of green tea each time, thrice a day for a one-year period.

RESULTS

LC-MS analysis revealed the presence of multiple phytocompounds along with catechins in green tea extract. Increased plasma lipid peroxidation (LPO), protein carbonyls, cholesterol, triglycerides, and LDL-cholesterol with decreased HDL-cholesterol levels were observed in smokers compared to the control group and the consumption of green tea showed beneficial effect. Furthermore, docking studies revealed that natural compounds of green tea had high binding capacity with 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMG-CoA) when compared to their positive controls, whereas (-) epigallocatechin-3-gallate (EGCG) and (-) epicatechin-gallate (ECG) had high binding capacity with sterol regulatory element-binding transcription factor 1 (SREBP1c). Further, our ex vivo studies showed that green tea extract (GTE) significantly inhibited platelet aggregation and increased thrombolytic activity in a dose dependent manner.

CONCLUSION

In conclusion, in smokers, catechins synergistically lowered oxidative stress, platelet aggregation and modified the aberrant lipid profile. Furthermore, molecular docking studies supported green tea catechins' antihyperlipidemic efficacy through strong inhibitory activity on HMG-CoA reductase and SREBP1c. The mitigating effects of green tea on cardiovascular disease risk factors in smokers that have been reported can be attributed majorly to catechins or to their synergistic effects.

Therapeutic approaches targeting aging and cellular senescence in Huntington's disease

Huntington's disease (HD) is a devastating neurodegenerative disease that is manifested by a gradual loss of physical, cognitive, and mental abilities. As the disease advances, age has a major impact on the pathogenic signature of mutant huntingtin (mHTT) protein aggregation. This review aims to explore the intricate relationship between aging, mHTT toxicity, and cellular senescence in HD. Scientific data on the interplay between aging, mHTT, and cellular senescence in HD were collected from several academic databases, including PubMed, Google Scholar, Google, and ScienceDirect. The search terms employed were "AGING," "HUNTINGTON'S DISEASE," "MUTANT HUNTINGTIN," and "CELLULAR SENESCENCE." Additionally, to gather information on the molecular mechanisms and potential therapeutic targets, the search was extended to include relevant terms such as "DNA DAMAGE," "OXIDATIVE STRESS," and "AUTOPHAGY." According to research, aging leads to worsening HD pathophysiology through some processes. As a result of the mHTT accumulation, cellular senescence is promoted, which causes DNA damage, oxidative stress, decreased autophagy, and increased inflammatory responses. Pro-inflammatory cytokines and other substances are released by senescent cells, which may worsen the neuronal damage and the course of the disease. It has been shown that treatments directed at these pathways reduce some of the HD symptoms and enhance longevity in experimental animals, pointing to a new possibility of treating the condition. Through their amplification of the harmful effects of mHTT, aging and cellular senescence play crucial roles in the development of HD. Comprehending these interplays creates novel opportunities for therapeutic measures targeted at alleviating cellular aging and enhancing HD patients' quality of life.

Optimizing Lactic Acid Bacteria Fermentation for Enhanced Summer and Autumn Tea Quality

The level of consumption of summer tea is a problem in the development of China's tea industry. Current strategies to enhance the quality of summer and autumn teas primarily target the cultivation environment, with less emphasis on processing improvements. This study aimed to optimize the fermentation parameters to impact the quality of summer and autumn teas. We screened four strains of lactic acid bacteria (LAB) suitable for tea fermentation and determined their optimal mix. This optimized blend was applied to ferment summer and autumn teas. Through single-factor experiments, we evaluated the impact of various processing parameters, including the fixation method, rolling degree, inoculation amount, glucose concentration, fermentation temperature, and fermentation duration, on LAB growth and tea quality. The optimal processing conditions were established as microwave fixation, heavy rolling, an inoculation rate of 1.8% LAB, glucose addition at 8.8%, and fermentation at 36.5 °C for five days. Analysis revealed that the fermentation process significantly reduced the levels of polyphenols and ester-type catechins, which are associated with astringency and bitterness while enhancing the content of gamma-aminobutyric acid (GABA). Specifically, after five days, polyphenol content decreased by 26.89%, and GABA levels increased from 0.051 mg/g to 0.126 mg/g. The predominant aroma compounds in the fermented tea were alcohols with floral and fruity scents, constituting 54.63% of the total aroma profile. This research presents a methodical approach to reduce the astringency and bitterness of summer and autumn teas while concurrently increasing GABA levels.

The impact of freeze-dried Baiyedancong-Oolong tea aqueous extract containing bioactive compounds on the activities of CYP450 enzymes, the transport capabilities of P-gp and OATs, and transcription levels in mice

In this study, (-)-epigallocatechin gallate (EGCG) and caffeine extracted from freeze-dried autumn Baiyedancong Oolong tea (FBOT) were orally administered to mice for 7 consecutive days to explore the effects of BOT and its bioactive compounds on the activities and transcription levels of CYP450 enzymes, intestinal effluence transporter P-gp, and renal ingestion Organic Anion Transporters (OATs). Concurrently, EGCG and caffeine enhanced the activities of CYP3A, CYP2E1, and CYP2C37 in the liver of mice, while impairing the transport capabilities of P-gp and OATs. Reduced levels of MDR1 encoding P-gp transcription in the small intestine and renal OAT1 and OAT3 revealed that transcription was involved in the regulation of CYP450, P-gp, and OATs. The reduced transcription level of liver CYP2E1 suggested that CYP2E1 activity may have been elevated due to alternative mechanisms, but not through transcription. The absorption, metabolism, and excretion of drugs may be influenced by the daily consumption or high-dose administration of BOT and its related products, in which EGCG and caffeine may make great contributions.

Bimetallic nanocolloidal plasmonic array for polyphenol characterization and calibration-free antioxidant capacity evaluation

A bimetallic plasmonic nanoparticles-based approach for the untargeted evaluation of phenolic compounds (PC)-pattern and antioxidant capacity (AoC) is proposed. The rationale relies on the PC's ability to drive the formation of bimetallic silver/gold nanocolloidal 'probes' with different conformations. Ag/Au bimetallic nanostructures, according to the PCs' amount and class, return characteristic plasmonic and colorimetric tags. Plasmonic indexes are proposed to assess the dominant PC classes, while the colorimetric response, analyzed simply by a smartphone, is employed to obtain an AoC score, without calibration. The methods were tested with PCs belonging to different chemical classes, and challenged to classify different food samples. The proposed approach allows PC-dominant class identification and AoC-evaluation consistent with HPLC-MS/MS and conventional photometric assays.

Treatment of water extract of green tea during kale cultivation using a home vertical farming appliance conveyed catechins into kale and elevated glucosinolate contents

The growing interest in healthy diets has driven the demand for food ingredients with enhanced health benefits. In this study, we aimed to explore a method to enhance the bioactivity of kale using a home vertical farming appliance. Specifically, we investigated the effects of treating kale with a green tea water extract (GTE; 0.1-0.5 g/L in nutrient solution) for two weeks before harvest during five weeks of kale cultivation. GTE treatment did not negatively affect the key quality attributes, such as yield, semblance, or sensory properties. However, it led to the accumulation of bioactive compounds, epicatechin (EC) and epigallocatechin gallate (EGCG), which are typically absent in kale. In the control group, no catechins were detected, whereas in the GTE-treated group, the concentration of EC and EGCG were as high as 252.11 and 173.26 μg/g, respectively. These findings indicate the successful incorporation of catechins, known for their unique health-promoting properties, into kale. Additionally, GTE treatment enhanced the biosynthesis of glucosinolates, which are key secondary metabolites of kale. The total glucosinolate content increased from 9.56 μmol/g in the control group to 16.81 μmol/g in the GTE-treated group (treated with 0.5 g/L GTE). These findings showed that GTE treatment not only enriched kale with catechins, the primary bioactive compounds in green tea but also increased the levels of glucosinolates. This study, conducted using a home vertical farming appliance, suggests that bioactivity-enhanced kale can be grown domestically, providing consumers with a nutrient-fortified food source.

Development of Epigallocatechin and Ascorbic Acid Dual Delivery Transferosomes for Managing Alzheimer's Disease: In Vitro and in Vivo Studies

Epigallocatechin-3-gallate (EGCG) and ascorbic acid (AA)-loaded transferosomes (TRANS) were developed for brain delivery. The investigation covered EGCG-TRANS, AA-TRANS, and EGCG-AA-TRANS formulations using the film hydration technique. We analyzed the formed transferosomes to confirm the presence of vesicles loaded with the respective drugs and their performance within a living organism. The sizes of the particles for EGCG-TRANS, AA-TRANS, and EGCG-AA-TRANS were measured correspondingly at 174.2 ± 1.80, 132.7 ± 12.22, and 184.31 ± 9.5 nm. The appearance of diffused rings in the scanning electron microscopic image suggests that the payload has a crystalline structure. The atomic force microscope image displayed minimal surface irregularities, potentially indicating the presence of a lipid layer on the surface. Hemolysis results indicated the safety of the vesicles. The results showed 10.23, 7.21, and 8.20% of hemolysis for EGCG-TRANS, AA-TRANS, and EGCG-AA-TRANS, respectively. In the case of EGCG-AA-TRANS, the release of EGCG was determined to be 61.65% ± 4.61 after 72 h when exposed to phosphate buffer saline (pH 7.4). In vivo studies show a good response against Alzheimer's disease (AD). EGCG-AA-TRANS (82.166%) exhibited a higher percentage of AChE inhibition in comparison to EGCG-TRANS (66.550%) and AA-TRANS (53.466%). Intranasal delivery of EGCG-AA-TRANS resulted in approximately a 5-fold enhancement in memory. Formulation allowed EGCG and AA to accumulate in various organs, including the brain. The results suggest that EGCG-AA-TRANS could be safe and effective for treating AD.

Zinc metal complexes synthesized by a green method as a new approach to alter the structural and optical characteristics of PVA: new field for polymer composite fabrication with controlled optical band gap

The current study employed a novel approach to design polymer composites with modified structural and declined optical band gaps. The results obtained in the present work for polymer composites can be considered an original method to make a new field for research based on green chemistry. Natural dyes extracted from green tea were mixed with hydrated zinc acetate (Zn(CH3COO)2·2H2O) to produce a metal complex. FTIR results comprehensively established the formation of the Zn-metal complex. The interaction among various components of PVA : Zn-metal complex composite was investigated using FTIR spectroscopy. The non-existence of anion bands of acetate in the Zn-metal complex spectrum confirms the formation of the Zn-metal complex. XRD analysis reveals that the Zn-metal complex improves the amorphous phase of the PVA-based composites. The absorption edge of the doped films shifted towards the lower photon energies. Optical dielectric properties were used to determine N/m*, ε ∞, τ, μ opt, ω p, and ρ opt; the W-D model was used to calculate E d, E o and n o parameters. The optical dielectric loss parameter was used to determine the optical band gap while the Tauc model was employed to identify various types of electron transitions. The optical energy band gap was 6.05 eV for clean PVA while it decreased to 1 eV for PVA inserted with the Zn-metal complex. The increase in Urbach energy from 0.26 eV to 0.45 eV is an evidence of the boost of amorphous phases in PVA : Zn-metal complex composites. The nonlinear refractive index and the first-order and second-order nonlinear optical susceptibilities were determined. The value of E o obtained from the W-D model closely matches the optical energy band gap obtained from the Tauc model, which indicates the precision of the analysis in the present study. The increase in SELF and VELF in the composite films establishes that new energy states assigned to the added Zn-metal complex amplify the probability of light-matter interaction.

Effects of instant controlled pressure drop treatment combined with refractance window drying on infusion quality of made green tea

BACKGROUND

The study aimed to determine the effects of instant controlled decompression of steam pressure, termed as ICPD (instant controlled pressure drop) on fresh tea leaves, when combined with refractance window drying (RWD) of rolled green teas during green tea manufacturing. The ICPD steam treatment pressure (TP; 0.1-0.3 MPa), treatment time (TT; 10-20 s) and refractance window drying temperature (RWDT; 70-90 °C) were used as the processing parameters for manufacturing of green tea.

RESULT

Response surface methodology was employed to enumerate the effects of ICPD process conditions and temperature of RWD on total phenolic content (TPC), total flavonoid content (TFC) and DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity of the green tea infusion. An optimum condition for green tea processing was found at TP 0.2 MPa, TT 20 s with RWDT at 70 °C. In comparison to made green tea manufactured without ICPD treatment, the ICPD treated green tea showed enhanced TPC, TFC and DPPH radical scavenging activity along with better colour and sensory attributes. The microstructural study of ICPD treated green tea samples showed more deformed cell surface integrity, larger stomatal pore size and cracks at the leaf surface in comparison with non-treated green tea sample.

CONCLUSION

Present study reveals that an ICPD treatment at 0.2 MPa for 20 s can be used as an alternative to the traditional enzyme inactivation step of hot water treatment, for green tea leaves to improve the infusion quality in terms of increased levels of TPC and TFC and DPPH radical scavenging activity. © 2024 Society of Chemical Industry.

Exploration of the molecular mechanism of tea polyphenols against pulmonary hypertension by integrative approach of network pharmacology, molecular docking, and experimental verification

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.

A nanoemulsified formulation of dolutegravir and epigallocatechin gallate inhibits HIV-1 replication in cellular models

Nanotechnology offers promising avenues for enhancing drug delivery systems, particularly in HIV-1 treatment. This study investigates a nanoemulsified formulation combining epigallocatechin gallate (EGCG) with dolutegravir (DTG) for managing HIV-1 infection. The combinatorial interaction between EGCG and DTG was explored through cellular, enzymatic, and molecular studies. In vitro assays demonstrated the potential of a dual drug-loaded nanoemulsion, NE-DTG-EGCG, in inhibiting HIV-1 replication, with EGCG serving as a supplementary treatment containing DTG. In silico molecular interaction studies highlighted EGCG's multifaceted inhibitory potential against HIV-1 integrase and reverse transcriptase enzymes. Further investigations are needed to validate the formulation's efficacy across diverse contexts. Overall, by integrating nanotechnology into drug delivery systems, this study represents a significant advancement in managing HIV-1 infection.

Lifestyle Medicine and Japan's Longevity Miracle

With Japan's economic growth, its life expectancy increased from 1965, and since 1980, Japan has become one of the longest-lived countries in the world. Strong government-led initiatives such as low-cost health insurance, widely distributed health screenings, a new law to prevent non-communicable diseases established in 1956, Shokuiku (Japanese culinary education), and stress-measuring systems in the workplace contributed to the population's longevity. In addition to these public initiatives, Japan has benefited from evolving lifestyle practices over its long history. These include Washoku (Japanese traditional food), which utilizes the complex interaction of individual nutrients unique to Japan as well as numerous metabolically active compounds, the interrelation of Japan's population levels with its plant-dominant diet, a mindful culture connected with nature, and the principle of hara-hachi-bu (Confucianism-based caloric restriction habit; "eat until 80% full"), and so on. In 2002, Japan took the remarkable action of stipulating by law that citizens must deepen their interest in and understanding of the importance of healthy lifestyle habits, be aware of their own health status, and strive to improve their health throughout their lives. Today, to protect its future, Japan must face a new challenge: a population that is declining and is the world's fastest-aging.

Advances in the Anti-Atherosclerotic Mechanisms of Epigallocatechin Gallate

Atherosclerosis (AS) is a common clinical sickness and the major pathological basis of ischemic cardiocerebrovascular diseases (CCVDs). The pathogenesis of AS involves a variety of risk factors, and there is a lack of effective preventive and curative drugs that can completely treat AS. In recent years, with the improvement of people's living standards and changes in dietary habits, the morbidity and mortality rates of AS are on the rise, and the age of onset tends to be younger. The formation of AS is closely related to a variety of factors, and the main factors include lipid metabolism disorders, endothelial damage, inflammation, unstable plaques, etc. Epigallocatechin gallate (EGCG), as one of the main components of catechins, has a variety of pharmacological effects, and its role in the prevention of AS and the protection of cardiovascular and cerebral blood vessels has been highly valued. Recent epidemiological investigations and various in vivo and ex vivo experiments have shown that EGCG is capable of resisting atherosclerosis and reducing the morbidity and mortality of AS. In this paper, we reviewed the anti-AS effects of EGCG and its mechanisms in recent years, including the regulation of lipid metabolism, regulation of intestinal flora disorders, improvement of vascular endothelial cell functions, inhibition of inflammatory factors expression, regulation of inflammatory signaling pathways, inhibition of matrix metalloproteinase (MMP) expression, and inhibition of platelet aggregation, which are helpful for the prevention of cardiocerebrovascular diseases.

Comparison of colorimetric methods for the analysis of total polyphenols in green tea extracts

Two colorimetric methods are used to determine the total polyphenol contents of tea, namely, "the Folin-Ciocalteu method," defined by the International Organization for Standardization, and the "iron tartrate method," specified in the Standard Tables of Food Composition in Japan. In this study, we compared the Folin-Ciocalteu and iron tartrate methods using green tea extracts. When comparing the 2 methods, the sum of the 4 major catechins measured using high-performance liquid chromatography (HPLC) was regarded as the standard value. The total polyphenol contents obtained using the Folin-Ciocalteu method were closer to the HPLC value than those obtained using the iron tartrate method. However, the iron tartrate method is adequate if the current official method is improved, that is, our results suggest that the coefficients appropriate for common green tea varieties, as well as the degree and duration of cover cultivation, in the official iron tartrate method must be considered.

Wound Healing Activity of Topical Herbal Gels Containing Barringtonia acutangula Fruit Extract: In silico and In vivo Studies

The current study describes the efficacy of B. acutangula fruit extract in wound healing via incorporation within topical gels. B. acutangula fruit extract was produced by solvent extraction method. The bioactive extract was incorporated within Carbopol 940-based topical gels, which were applied topically over the excision and incision wounds. The change in healing process was observed till 20 days. The percentages of closure of excision wound area were 92.89 % and 93.43 %, when treated with topical herbal gels containing B. acutangula fruit extract of 5 % and 10 %, respectively. The tensile strengths of incision area in rats treated with topical herbal gels containing 5 % and 10 % methanol extract of B. acutangula fruits were found to be 25±5.12 g and 30±4.10 g, respectively. The wound healing activity of topical herbal gels containing B. acutangula fruit extract in rats was found to be significant when compared with that of the reference standard and untreated groups. In addition, in silico studies suggested about good skin permeability and binding to the proteins responsible for delaying wound healing. It can be concluded that this topical herbal gels containing B. acutangula fruit extract could be used clinically for the treatment of wounds.

Common Beverage Consumption and Benign Gynecological Conditions

The purpose of this article is to review the effects of four commonly consumed beverage types-sugar-sweetened beverages (SSBs), caffeinated beverages, green tea, and alcohol-on five common benign gynecological conditions: uterine fibroids, endometriosis, polycystic ovary syndrome (PCOS), anovulatory infertility, and primary dysmenorrhea (PD). Here we outline a plethora of research, highlighting studies that demonstrate possible associations between beverage intake and increased risk of certain gynecological conditions-such as SSBs and dysmenorrhea-as well as studies that demonstrate a possible protective effect of beverage against risk of gynecological condition-such as green tea and uterine fibroids. This review aims to help inform the diet choices of those with the aforementioned conditions and give those with uteruses autonomy over their lifestyle decisions.

A Nuclear Magnetic Resonance (NMR)- and Mass Spectrometry (MS)-Based Saturation Kinetics Model of a Bryophyllum pinnatum Decoction as a Treatment for Kidney Stones

Bryophyllum pinnatum (BP) is a medicinal plant used to treat many conditions when taken as a leaf juice, leaves in capsules, as an ethanolic extract, and as herbal tea. These preparations have been chemically analyzed except for decoctions derived from boiled green leaves. In preparation for a clinical trial to validate BP tea as a treatment for kidney stones, we used NMR and MS analyses to characterize the saturation kinetics of the release of metabolites. During boiling of the leaves, (a) the pH decreased to 4.8 within 14 min and then stabilized; (b) regarding organic acids, citric and malic acid were released with maximum release time (tmax) = 35 min; (c) for glycoflavonoids, quercetin 3-O-α-L-arabinopyranosyl-(1 → 2)-α-L-rhamnopyranoside (Q-3O-ArRh), myricetin 3-O-α-L-arabinopyranosyl-(1 → 2)-α-L-rhamnopyranoside (M-3O-ArRh), kappinatoside, myricitrin, and quercitrin were released with tmax = 5-10 min; and (d) the total phenolic content (TPC) and the total antioxidant capacity (TAC) reached a tmax at 55 min and 61 min, respectively. In summary, 24 g of leaves boiled in 250 mL of water for 61 min ensures a maximal release of key water-soluble metabolites, including organic acids and flavonoids. These metabolites are beneficial for treating kidney stones because they target oxidative stress and inflammation and inhibit stone formation.

Biophysical insight into the binding mechanism of epigallocatechin-3-gallate and cholecalciferol to albumin and its preventive effect against AGEs formation: An in vitro and in silico approach

Advanced glycation end products (AGEs) are produced non-enzymatically through the process of glycation. Increased AGEs production has been linked to several diseases including polycystic ovary syndrome (PCOS). PCOS contributes to the development of secondary comorbidities, such as diabetes, cardiovascular complications, infertility, etc. Consequently, research is going on AGEs-inhibiting phytochemicals for their potential to remediate and impede the progression of hyperglycaemia associated disorders. In this study human serum albumin is used as a model protein, as albumin is predominantly present in follicular fluid. This article focusses on the interaction and antiglycating potential of (-)-Epigallocatechin-3-gallate (EGCG) and vitamin D in combination using various techniques. The formation of the HSA-EGCG and HSA-vitamin D complex was confirmed by UV and fluorescence spectroscopy. Thermodynamic analysis verified the spontaneity of reaction, and presence of hydrogen bonds and van der Waals interactions. FRET confirms high possibility of energy transfer. Cumulative antiglycation resulted in almost 60 % prevention in AGEs formation, decreased alterations at lysine and arginine, and reduced protein carbonylation. Secondary and tertiary structural changes were analysed by circular dichroism, Raman spectroscopy and ANS binding assay. Type and size of aggregates were confirmed by Rayleigh and dynamic light scattering, ThT fluorescence, SEM and SDS-PAGE. Effect on cellular redox status, DNA integrity and cytotoxicity was analysed in lymphocytes using dichlorofluorescein (DCFH-DA), DAPI and MTT assay which depicted an enhancement in antioxidant level by cumulative treatment. These findings indicate that EGCG and vitamin D binds strongly to HSA and have antiglycation ability which enhances upon synergism.

Complementary and alternative medicines and liver disease

Complementary and alternative medicines (CAM) include conventional medical treatments. Patients worldwide use CAM at alarming rates; thus, reports of CAM-related DILI have been on the rise. The clinical presentations include asymptomatic liver test abnormalities, acute hepatitis with or without jaundice, acute cholestatic liver disease (bland or with hepatitis), acute liver failure, severe hepatitis with features of portal hypertension, and acute decompensation of known or unknown cirrhosis that can lead to acute-on-chronic liver failure. Acute hepatitis with or without necrosis, hepatocellular and canalicular cholestasis, herb-induced or CAM-triggered autoimmune hepatitis, granulomatous hepatitis, severe steatohepatitis, and vanishing bile duct syndrome are common liver biopsy findings in CAM-DILI. The presence of preexisting liver disease predicts severe liver injury, risk of progression to liver failure, and decreased transplant-free survival in patients with CAM-DILI. This review discusses global epidemiology and trends in CAM-DILI, clinical presentation, assessment and outcomes, commonly emerging threats in the context of hepatotoxic herbs, pragmatic assessment of "liver beneficial" herbs and health care myths, patient communication, regulatory framework, and future directions on research in CAM.

Vegetal Polyphenol Extracts as Antioxidants for the Stabilization of PLA: Toward Fully Biobased Polymer Formulation

The use of natural antioxidants as substitutes for traditional synthetic stabilizers has been investigated for the stabilization of biobased and biodegradable polymers, with the aim of designing fully biobased plastic formulations. This study focused on the thermo- and photostabilization of poly(lactic acid) (PLA) using vegetal polyphenol extracts as biosourced antioxidants. The polyphenols were extracted by microwave-assisted extraction from the valorization of vegetal waste, and their potential as antioxidant additives was evaluated (e.g., polyphenol content, composition, and antioxidant activity). PLA was then formulated with 2 wt % of the extracts exhibiting the highest antioxidant activities: green tea residues, pomegranate peels, grape marc, bramble leaves, and yellow onion peel extracts. The efficiency of the natural additives as thermal stabilizers was evaluated and compared with a synthetic antioxidant using rheological and thermal analyses. The results demonstrated the capacity of grape marc extract and pomegranate peel extract to significantly improve PLA thermal stability during processing and thermo-oxidation. Finally, photorheology was conducted to evaluate the influence of the bioadditives on the biopolyester photodegradation. The different polyphenol extracts seemed to significantly hinder the photo-oxidation of PLA and constitute very promising natural UV stabilizers, combining UV absorbers and antioxidant functions.

A randomized placebo-controlled clinical trial of oral green tea epigallocatechin 3-gallate on erythropoiesis and oxidative stress in transfusion-dependent β-thalassemia patients

β-Thalassemia patients suffer from ineffective erythropoiesis and increased red blood cell (RBC) hemolysis. Blood transfusion, erythropoietic enhancement, and antioxidant supplementation can ameliorate chronic anemia. Green tea extract (GTE) is comprised of catechin derivatives, of which epigallocatechin-3-gallate (EGCG) is the most abundant, presenting free-radical scavenging, iron-chelating, and erythropoiesis-protective effects. The present study aimed to evaluate the effects of GTE tablets on the primary outcome of erythropoiesis and oxidative stress parameters in transfusion-dependent β-thalassemia (TDT) patients. Twenty-seven TDT patients were randomly divided into placebo and GTE tablet (50 and 100 mg EGCG equivalent) groups and assigned to consume the product once daily for 60 days. Blood was collected for analysis of hematological, biochemical, and oxidative stress parameters. Accordingly, consumption of GTE tablets improved blood hemoglobin levels when compared with the placebo; however, there were more responders to the GTE tablets. Interestingly, amounts of nonheme iron in RBC membranes tended to decrease in both GTE tablet groups when compared with the placebo. Importantly, consumption of GTE tablets lowered plasma levels of erythroferrone (p < 0.05) and reduced bilirubin non-significantly and dose-independently. Thus, GTE tablets could improve RBC hemolysis and modulate erythropoiesis regulators in transfusion-dependent thalassemia patients.

New Trends to Treat Muscular Atrophy: A Systematic Review of Epicatechin

Epicatechin is a polyphenol compound that promotes skeletal muscle differentiation and counteracts the pathways that participate in the degradation of proteins. Several studies present contradictory results of treatment protocols and therapeutic effects. Therefore, the objective of this systematic review was to investigate the current literature showing the molecular mechanism and clinical protocol of epicatechin in muscle atrophy in humans, animals, and myoblast cell-line. The search was conducted in Embase, PubMed/MEDLINE, Cochrane Library, and Web of Science. The qualitative analysis demonstrated that there is a commonness of epicatechin inhibitory action in myostatin expression and atrogenes MAFbx, FOXO, and MuRF1. Epicatechin showed positive effects on follistatin and on the stimulation of factors related to the myogenic actions (MyoD, Myf5, and myogenin). Furthermore, the literature also showed that epicatechin can interfere with mitochondrias' biosynthesis in muscle fibers, stimulation of the signaling pathways of AKT/mTOR protein production, and amelioration of skeletal musculature performance, particularly when combined with physical exercise. Epicatechin can, for these reasons, exhibit clinical applicability due to the beneficial results under conditions that negatively affect the skeletal musculature. However, there is no protocol standardization or enough clinical evidence to draw more specific conclusions on its therapeutic implementation.

Combined effects of green tea supplementation and eccentric exercise on nuclear factor erythroid 2-related factor 2 activity

PURPOSE

This study investigated whether combining eccentric exercise and green tea supplementation synergistically increased nuclear factor erythroid 2-related factor 2 (NRF2) activity, a transcription factor responsible for coordinating endogenous antioxidant expression.

METHODS

In a double-blinded, randomized, between-subjects design, 24 males (mean [SD]; 23 [3] years, 179.6 [6.1] cm, 78.8 [10.6] kg) performed 100 drop jumps following a 6 days supplementation period with either green tea (poly)phenols (n = 12; 500 mg·d-1) or a placebo (n = 12; inulin). NRF2/antioxidant response element (ARE) binding in peripheral blood mononuclear cells (PBMCs), catalase (CAT) and glutathione reductase (GR) activity, 8-hydroxy-2'-deoxyguanosine (8-OHdG) excretion, and differential leukocyte counts were measured pre-, post-, 1 h and 24 h post-exercise.

RESULTS

Exercise did not increase NRF2/ARE binding (p = 0.12) (fold change vs rest: green tea = [post] 0.78 ± 0.45, [1 h] 1.17 ± 0.54, [24 h] 1.06 ± 0.56; placebo = [post] 1.40 ± 1.50, [1 h] 2.98 ± 3.70, [24 h] 1.04 ± 0.45). Furthermore, CAT activity (p = 0.12) and 8-OHdG excretion (p = 0.42) were unchanged in response to exercise and were not augmented by green tea supplementation (p > 0.05 for all). Exercise increased GR activity by 30% (p = 0.01), however no differences were found between supplement groups (p = 0.51). Leukocyte and neutrophil concentrations were only elevated post-exercise (p < 0.001 for all).

CONCLUSION

Eccentric exercise, either performed alone or in conjunction with green tea supplementation, did not significantly increase NRF2 activity in PBMCs.

TRIAL REGISTRATION NUMBER

osf.io/kz37g (registered: 15/09/21).

Changing Trends Towards Herbal Supplements: An Insight into Safety and Herb-drug Interaction

Herbs have been used as sustenance and medicine for a very long time, often in conjunction with other prescribed medications. Even though they are thought to be natural and secure, many of these herbs can interact with other medications and cause potentially dangerous adverse effects or decrease the benefits of the medication. The complex and diverse pharmacological functions carried out by the active ingredients in herbs unavoidably alter the pharmacokinetics of chemical drugs when administered in vivo. Drug transporter expression has a direct impact on how medications are absorbed, distributed, metabolized, and excreted in living organisms. Changes in substrate pharmacokinetics can affect the effectiveness and toxicity of a drug when the active ingredients of a herb inhibit or stimulate the expression of transporters. By reviewing published clinical and preclinical studies, this review aims to raise awareness of herbdrug interactions and discuss their evidence-based mechanisms and clinical consequences. More clinical information on herb-drug interactions is required to make choices regarding patient safety as the incidence and severity of herb-drug interactions are rising due to an increase in the use of herbal preparations globally.This review seeks to increase understanding of herb-drug interactions and explore their evidence-based mechanisms and clinical implications by reviewing published clinical and preclinical studies. The incidence and severity of herb-drug interactions are on the rise due to an increase in the use of herbal preparations worldwide, necessitating the need for more clinical data on these interactions in order to make decisions regarding patient safety. Healthcare workers and patients will become more alert to potential interactions as their knowledge of pharmacokinetic herb-drug interactions grows. The study's objective is to raise readers' awareness of possible interactions between herbal supplements and prescription medications who regularly take them.

Functional Ingredients Associated with the Prevention and Suppression of Locomotive Syndrome: A Review

In 2007, the Japanese Orthopaedic Association proposed the concept of locomotive syndrome, a comprehensive description of conditions involving the functional decline of the locomotor system. Locomotive syndrome includes bone-related diseases such as osteoporosis, joint cartilage and disc-related diseases such as osteoarthritis and lumbar spondylosis, and sarcopenia and locomotive syndrome-related diseases. If left untreated, these diseases are likely to reduce mobility, necessitating nursing care. To prevent the progression of locomotive syndrome, a daily exercise routine and well-balanced diet are important, in addition to recognizing one's own decline in mobility. Therefore, research on the effectiveness of functional ingredients in the prevention and suppression of locomotive syndrome progression is ongoing. In this review, we summarize the latest reports on the effectiveness of five functional ingredients, namely, epigallocatechin gallate, resveratrol, curcumin, ellagic acid, and carnosic acid, in the treatment of osteoarthritis, osteoporosis, and rheumatoid arthritis, which are considered representative diseases of the locomotive syndrome.

The intestinal-level metabolic benefits of green tea catechins: Mechanistic insights from pre-clinical and clinical studies

BACKGROUND

The intestinal-level host-microbiota interaction has been implicated in the pathogenesis of chronic diseases. The current review is intended to provide a comprehensive insight into deciphering whether intestinal-level bioactivities mediate the overall metabolic health benefits of green tea catechins.

PURPOSE

We have comprehensively discussed pre-clinical and clinical evidences of intestinal-level changes in metabolism, microbiota, and metabolome due to catechin-rich green tea treatments, ultimately limiting metabolic diseases. Exclusive emphasis has been given to purified catechins and green tea, and discussions on extraintestinal mechanisms of metabolic health benefits were avoided.

METHODS

A literature search for relevant pre-clinical and clinical studies was performed in various online databases (e.g., PubMed) using specific keywords (e.g., catechin, intestine, microbiota). Out of all the referred literature, ∼15% belonged to 2021-2023, ∼51% were from 2011-2020, and ∼32% from 2000-2010.

RESULT

The metabolic health benefits of green tea catechins are indeed influenced by the intestinal-level bioactivities, including reduction of mucosal inflammation and oxidative stress, attenuation of gut barrier dysfunction, decrease in intestinal lipid absorption and metabolism, favorable modulation of mucosal nuclear receptor signaling, alterations of the luminal global metabolome, and mitigation of the gut dysbiosis. The results from the recent clinical studies support the pre-clinical evidences. The challenges and pitfalls of the currently available knowledge on catechin bioactivities have been discussed, and constructive directions to harness the translational benefits of green tea through future interventions have been provided.

CONCLUSION

The metabolism, metabolome, and microbiota at the intestinal epithelia play critical roles in catechin metabolism, pharmacokinetics, bioavailability, and bioactivities. Especially the reciprocal interaction between the catechins and the gut microbiota dictates the metabolic benefits of catechins.

Green tea polyphenols improved the physicochemical stability of mango powder during storage

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.

Epigallocatechin gallate delays age-related cataract development via the RASSF2/AKT pathway

Age-related cataract (ARC) is a common eye disease, the main cause of which is oxidative stress-mediated apoptosis of lens epithelial cells (LECs). Epigallocatechin gallate (EGCG) is the most potent antioxidant in green tea. Our results demonstrated that EGCG could effectively reduce apoptosis of LECs and retard lens clouding in aged mice. By comparing transcriptome sequencing results of three groups of mice (young control, untreated aged, and EGCG-treated) and screening using GO and KEGG analyses, we selected RASSF2 as the effector gene of EGCG for mechanistic exploration. We verified that the differential expression of RASSF2 was associated with the occurrence of ARC in clinical samples and mouse tissues by immunohistochemistry and western blotting, respectively. We showed that high RASSF2 expression plays a crucial role in the oxidative induction of apoptosis in LECs, as revealed by overexpression and interference experiments. Further studies showed that RASSF2 mediates the inhibitory effect of EGCG on apoptosis and ARCogenesis in LECs by regulating AKT (Ser473) phosphorylation. In this study, we found for the first time the retarding effect of EGCG on lens clouding in mice and revealed the mechanism of action of RASSF2/AKT in it, which provides a theoretical basis for the targeted treatment of EGCG.

Tea-break with epigallocatechin gallate derivatives - Powerful polyphenols of great potential for medicine

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.

Undifferentiated Cells of Tessaria absinthioides with High Nutritional Value and Health-Promoting Phytochemicals. An Approach Based on Plant Cellular Agriculture

In vitro cultures of undifferentiated plant cells of Tessaria absinthioides, a native herb popularly recognized and used for its health benefits, were studied as potential food supplements. These tissues were incubated under two light conditions, and the biomass obtained was freeze-dried and oven-dried. To evaluate their nutritional value, their physicochemical and functional properties were determined. Although in some cases there were significant differences in the results according to the drying methodology applied, all these tissues presented a high proportion of proteins (23.6-28.3%), a low percentage of fats (< 2%) constituted mainly by phytosterols, and a significant amount of crude fibers (6.9-9.0%) and ashes (> 10%). In addition, the freeze-dried calli resulted in a product with better functional properties. On the other hand, their phytochemical profiles and antioxidant capacity were studied and compared with tissues from wild specimens and with green tea and chamomile as reference extracts.

Epigallocatechin gallate inhibits ovarian cancer cell growth and induces cell apoptosis via activation of FOXO3A

Epigallocatechin gallate (EGCG), a bioactive component in tea, displays broad anti-cancer effects. Our study was designed to evaluate the anti-cancer effects of EGCG on ovarian cancer and explored the underlying molecular mechanisms. To evaluate the in vitro inhibitory effects of EGCG against ovarian cancer, MTT assay, colony formation assay, apoptosis assay, and wound healing assay, were performed. Besides, the inhibitory effects of EGCG on tumor growth in the xenograft animal model were evaluated by measuring tumor volume and tumor weight. Moreover, Western blotting and qPCR were used to evaluate the levels of target genes and proteins. Treatment with EGCG inhibited cell migration and cell survival, and promoted cell apoptosis in A2780 and SKOV3 cells. Interestingly, treatment with EGCG inhibited the tumor growth in the xenograft animal model. The mechanistic study revealed that treatment with EGCG induced the activation of FOXO3A and suppressed the expression of c-Myc both in vitro and in vivo. Our findings demonstrate that EGCG suppress ovarian cancer cell growth, which may be due to its regulation on FOXO3A and c-Myc.

Assessing the Protective Role of Epigallocatechin Gallate (EGCG) against Water-Pipe Smoke-Induced Toxicity: A Comparative Study on Gene Expression and Histopathology

Exposure to water-pipe smoking, whether flavored or unflavored, has been shown to instigate inflammation and oxidative stress in BALB/c mice. This consequently results in alterations in the expression of inflammatory markers and antioxidant genes. This study aimed to scrutinize the impact of Epigallocatechin gallate (EGCG)-a key active component of green tea-on inflammation and oxidative stress in BALB/c mice exposed to water-pipe smoke. The experimental setup included a control group, a flavored water-pipe smoke (FWP) group, an unflavored water-pipe smoke (UFWP) group, and EGCG-treated flavored and unflavored groups (FWP + EGCG and UFWP + EGCG). Expression levels of IL-6, IL1B, TNF-α, CAT, GPXI, MT-I, MT-II, SOD-I, SOD-II, and SOD-III were evaluated in lung, liver, and kidney tissues. Histopathological changes were also assessed. The findings revealed that the EGCG-treated groups manifested a significant decline in the expression of inflammatory markers and antioxidant genes compared to the FWP and UFWP groups. This insinuates that EGCG holds the capacity to alleviate the damaging effects of water-pipe smoke-induced inflammation and oxidative stress. Moreover, enhancements in histopathological features were observed in the EGCG-treated groups, signifying a protective effect against tissue damage induced by water-pipe smoking. These results underscore the potential of EGCG as a protective agent against the adverse effects of water-pipe smoking. By curbing inflammation and oxidative stress, EGCG may aid in the prevention or mitigation of smoking-associated diseases.

Evidence-Based Approach for Secondary Prevention of Uterine Fibroids (The ESCAPE Approach)

Uterine fibroids (UFs) are common tumors in women of reproductive age. It is imperative to comprehend UFs' associated risk factors to facilitate early detection and prevention. Simple relying on surgical/pharmacological treatment of advanced disease is not only highly expensive, but it also deprives patients of good quality of life (QOL). Unfortunately, even if the disease is discovered early, no medical intervention is traditionally initiated until the disease burden becomes high, and only then is surgical intervention performed. Furthermore, after myomectomy, the recurrence rate of UFs is extremely high with the need for additional surgeries and other interventions. This confused approach is invasive and extremely costly with an overall negative impact on women's health. Secondary prevention is the management of early disease to slow down its progression or even halt it completely. The current approach of watchful observation for early disease is considered a major missed opportunity in the literature. The aim of this article is to present an approach named the ESCAPE (Evidence-Based Approach for Secondary Prevention) of UF management. It comprises simple, inexpensive, and safe steps that can arrest the development of UFs, promote overall reproductive health, decrease the number of unnecessary surgeries, and save billions of health care systems' dollars worldwide.

Catechin hydrate ameliorates cerulein‑induced chronic pancreatitis via the inactivation of TGF‑β/Smad2 signaling

Chronic pancreatitis (CP) is a pancreatic inflammatory disease associated with histological changes, including fibrosis, acinar cell loss and immune cell infiltration, and leads to damage of the pancreas, which results in pain, weight loss and loss of pancreas function. Catechin or catechin hydrate (CH) has antioxidant, anticancer and immune‑regulatory effects. However, unlike other catechins, the antifibrotic effects of (+)‑CH have not been widely studied in many diseases, including CP. Therefore, the anti‑fibrotic effects of (+)‑CH against CP were evaluated in the present study. To assess the prophylactic effects of CH, (+)‑CH (1, 5 or 10 mg/kg) or ethanol was administered 1 h before first cerulein (50 µg/kg) injection. To assess the therapeutic effects, (+)‑CH (5 mg/kg) or ethanol was administered after cerulein injection for one or two weeks. In both methods, cerulein was injected intraperitoneally into mice once every hour, six times a day, four times a week, for a total of three weeks, to induce CP. The data showed that (+)‑CH markedly inhibited glandular destruction and inflammation during CP. Moreover, (+)‑CH prevented pancreatic stellate cell (PSC) activation and the production of extracellular matrix components, such as fibronectin 1 and collagens, which suggested that it may act as a novel therapeutic agent. Furthermore, the mechanism and effectiveness of (+)‑CH on pancreatic fibrosis were investigated in isolated PSCs. (+)‑CH suppressed the activation of Smad2 and fibrosis factors that act through transforming growth factor‑β (TGF‑β) or platelet‑derived growth factor. These findings suggest that (+)‑CH exhibits antifibrotic effects in cerulein‑induced CP by inactivating TGF‑β/Smad2 signaling.

Co-consuming green tea with raloxifene decreases raloxifene systemic exposure in healthy adult participants

Green tea is a popular beverage worldwide. The abundant green tea catechin (-)-epigallocatechin gallate (EGCG) is a potent in vitro inhibitor of intestinal UDP-glucuronosyltransferase (UGT) activity (Ki  ~2 μM). Co-consuming green tea with intestinal UGT drug substrates, including raloxifene, could increase systemic drug exposure. The effects of a well-characterized green tea on the pharmacokinetics of raloxifene, raloxifene 4'-glucuronide, and raloxifene 6-glucuronide were evaluated in 16 healthy adults via a three-arm crossover, fixed-sequence study. Raloxifene (60 mg) was administered orally with water (baseline), with green tea for 1 day (acute), and on the fifth day after daily green tea administration for 4 days (chronic). Unexpectedly, green tea decreased the geometric mean green tea/baseline raloxifene AUC0-96h ratio to ~0.60 after both acute and chronic administration, which is below the predefined no-effect range (0.75-1.33). Lack of change in terminal half-life and glucuronide-to-raloxifene ratios indicated the predominant mechanism was not inhibition of intestinal UGT. One potential mechanism includes inhibition of intestinal transport. Using established transfected cell systems, a green tea extract normalized to EGCG inhibited 10 of 16 transporters tested (IC50 , 0.37-12 μM). Another potential mechanism, interruption by green tea of gut microbe-mediated raloxifene reabsorption, prompted a follow-up exploratory clinical study to evaluate the potential for a green tea-gut microbiota-drug interaction. No clear mechanisms were identified. Overall, results highlight that improvements in current models and methods used to predict UGT-mediated drug interactions are needed. Informing patients about the risk of co-consuming green tea with raloxifene may be considered.

Antibacterial efficacy of epigallocatechin-3-gallate cross-linked small intestinal submucosa guided bone regeneration membrane

The leading cause of guided bone regeneration (GBR) failure is infection. Herein, we developed a new GBR membrane with good mechanical and osteogenic properties by crosslinking the small intestinal submucosa (SIS) with epigallocatechin-3-gallate (EGCG). Meanwhile, EGCG is also a natural antibacterial agent. This study aimed to investigate the antibacterial efficacy of EGCG-crosslinked SIS (E-SIS) against Staphylococcus aureus and Escherichia coli through EGCG release, bacterial count, live/dead staining, scanning electron microscopy, growth curve, and biofilm formation tests. The results showed that E-SIS effectively inhibited bacteria's growth and adhesion, and its antibacterial activity against Staphylococcus aureus was stronger than that against Escherichia coli. 0.5% E-SIS had the most potent antibacterial activity. The antibacterial mechanism of E-SIS might be related to the release of EGCG and the surface properties of E-SIS. In conclusion, 0.5% E-SIS is a promising GBR membrane with good osteogenic and antibacterial properties.

Camellia sinensis (L.) Kuntze Extract Attenuates Ovalbumin-Induced Allergic Asthma by Regulating Airway Inflammation and Mucus Hypersecretion

Asthma is a pulmonary disease induced by the inhalation of aeroallergens and subsequent inappropriate immune responses. Camellia sinensis (L.) Kuntze has been evaluated as an effective antioxidant supplement produced from bioactive compounds, including flavonoids. In this study, we aimed to determine the effects of Camellia sinensis (L.) Kuntze extract (CE) on ovalbumin-induced allergic asthma. The components of CE were analyzed using high-performance liquid chromatography (HPLC) chromatogram patterns, and asthmatic animal models were induced via ovalbumin treatment. The antioxidant and anti-inflammatory effects of CE were evaluated using 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), and nitric oxide (NO) assays. Seven compounds were detected in the CE chromatogram. In the ovalbumin-induced mouse model, CE treatment significantly decreased the inflammation index in the lung tissue. CE also significantly decreased eosinophilia and the production of inflammatory cytokines and OVA-specific IgE in animals with asthma. Collectively, our results indicate that CE has anti-inflammatory and antioxidant activities, and that CE treatment suppresses asthmatic progression, including mucin accumulation, inflammation, and OVA-specific IgE production.

Epigallocatechin Gallate: A Multifaceted Molecule for Neurological Disorders and Neurotropic Viral Infections

Epigallocatechin-3-gallate (EGCG), a polyphenolic moiety found in green tea extracts, exhibits pleiotropic bioactivities to combat many diseases including neurological ailments. These neurological diseases include Alzheimer's disease, multiple sclerosis, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis. For instance, in the case of Alzheimer's disease, the formation of a β-sheet in the region of the 10th-21st amino acids was significantly reduced in EGCG-induced oligomeric samples of Aβ40. Its interference induces the formation of Aβ structures with an increase in intercenter-of-mass distances, reduction in interchain/intrachain contacts, reduction in β-sheet propensity, and increase in α-helix. Besides, numerous neurotropic viruses are known to instigate or aggravate neurological ailments. It exerts an effect on the oxidative damage caused in neurodegenerative disorders by acting on GSK3-β, PI3K/Akt, and downstream signaling pathways via caspase-3 and cytochrome-c. EGCG also diminishes these viral-mediated effects, such as EGCG delayed HSV-1 infection by blocking the entry for virions, inhibitory effects on NS3/4A protease or NS5B polymerase of HCV and potent inhibitor of ZIKV NS2B-NS3pro/NS3 serine protease (NS3-SP). It showed a reduction in the neurotoxic properties of HIV-gp120 and Tat in the presence of IFN-γ. EGCG also involves numerous viral-mediated inflammatory cascades, such as JAK/STAT. Nonetheless, it also inhibits the Epstein-Barr virus replication protein (Zta and Rta). Moreover, it also impedes certain viruses (influenza A and B strains) by hijacking the endosomal and lysosomal compartments. Therefore, the current article aims to describe the importance of EGCG in numerous neurological diseases and its inhibitory effect against neurotropic viruses.

The Dunning-Kruger effect: subjective health perceptions on smoking behavior among older Chinese adults

BACKGROUND

The intrinsic damage and external hazards of smoking are major risk factors for poorer health and are recognized as a global health issue of concern in geriatric health. This study aims to assess the Dunning-Kruger effect through the influence of subjective health perceptions on smoking behavior in older adults.

METHODS

This study used data from the 2018 Chinese Longitudinal Healthy Longevity Survey (N = 9,683) provided by the Center for Healthy Aging and Development Studies at Peking University. A binary logistic model was used to examine whether the Dunning-Kruger effect affects smoking behavior in older adults, and a linear probability model was used as a commentary baseline model for logistic regression to prevent measurement bias. In addition, a mediating analysis was used to examine the mechanisms through which the Dunning-Kruger effect occurs.

RESULTS

Older adults often overestimated their current health status and underestimated the health risks of smoking, causing the Dunning-Kruger effect to arise from their inadequate self-perceived health (i.e., older adults are more likely to smoke when they have better self-rated health or when hypertension, cardiopathy, stroke, and diabetes have little or no impact on their daily lives). These observations can be explained by the older adults' subjective health perceptions arising from their ingenuous understanding of their health, which indirectly influences their smoking behavior to some extent.

CONCLUSION

Older adults' self-perceived health was associated with smoking behavior. Public health institutions should improve older adults' health perceptions so that they objectively understand their own health status.