Bioavailability Of Epigallocatechin-3-gallate Research Articles

Multifunctional EGCG@ZIF-8 Nanoplatform with Photodynamic Therapy/Chemodynamic Therapy Antibacterial Properties Promotes Infected Wound Healing.

Damaged skin is susceptible to invasion by harmful microorganisms, especially Staphylococcus aureus and Escherichia coli, which can delay healing. Epigallocatechin-3-gallate (EGCG) is a natural compound known for effectively promoting wound healing and its potent anti-inflammatory effects. However, its application is limited due to its susceptibility to oxidation and isomerization, which alter its structure. The use of zeolitic imidazolate framework-8 (ZIF-8) can effectively tackle these issues. This study introduces an oxygen (O2) and hydrogen peroxide (H2O2) self-supplying ZIF-8 nanoplatform designed to enhance the bioavailability of EGCG, combining photodynamic therapy (PDT) and chemodynamic therapy (CDT) to improve antibacterial properties and ultimately accelerate wound healing. For this purpose, EGCG and indocyanine green (ICG), a photosensitizer, were successively integrated into a ZIF-8, and coated with bovine serum albumin (BSA) to enhance biocompatibility. The outer layer of this construct was further modified with manganese dioxide (MnO2) to promote CDT and calcium peroxide (CaO2) to supply H2O2 and O2, resulting in the final nanoplatform EGCG-ICG@ZIF-8/BSA-MnO2/CaO2 (EIZBMC). In in vitro experiments under 808 nm laser, EIZBMC exhibited synergistic antibacterial effects through PDT and CDT. This combination effectively released reactive oxygen species (ROS), which mediated oxidative stress to inhibit the bacteria. Subsequently, in a murine model of wound infection, EIZBMC not only exerted antibacterial effects through PDT and CDT but also alleviated the inflammatory condition and promoted the regeneration of collagen fibers, which led to accelerated wound healing. Overall, this research presents a promising approach to enhancing the therapeutic efficacy of EGCG by leveraging the synergistic antibacterial effects of PDT and CDT. This multifunctional nanoplatform maximizes EGCG's anti-inflammatory properties, offering a potent solution for promoting infected wound healing.

Enhanced skin benefits of EGCG loaded in nonapeptide-1-conjugated mesoporous silica nanoparticles to reverse skin photoaging

Epigallocatechin-3-gallate (EGCG), a catechin present in green tea, has been studied extensively for its potential as a cosmetic ingredient due to its various biological properties. However, the low stability and bioavailability of EGCG have hindered its effective utilization in cosmetic applications. This study, to improve the stability and bioavailability of EGCG for reversing skin photo-aging, nonapeptide-1-conjugated mesoporous silica nanoparticles (EGCG@NP-MSN) were fabricated to load EGCG. MSNs can regulate the EGCG release and provide ultraviolet light (UV) protection to possess excellent photostability. Nonapeptide-1 exhibits melanin transfer interference properties and reduces the melanin content in treated skin areas. In vitro and in vivo results confirmed that the EGCG-loaded MSNs retained antioxidant properties, effectively scavenged the melanin and significantly reduced the deoxyribonucleic acid (DNA) damage in skin cells exposed to UV irradiation. The melanin inhibition rate is 5.22 times and the tyrosinase inhibition rate is 1.57 times that of free EGCG. The utilization of this innovative platform offers the potential for enhanced stability, controlled release, and targeted action of EGCG, thereby providing significant advantages for skin application.This delivery system combines the advantages of antioxidant, anti-aging, and anti-UV radiation properties, paving the way for the cosmetics development with improved efficacy and better performance in promoting skin health and appearance.

Gut Microbiota-Derived D-Tagatose from EGCG Attenuates Radiation-Induced Intestinal Injury

As a rapidly self-renewing tissue, the small intestine is particularly sensitive to ionizing radiation, which limits the outcomes of radiotherapy against abdominal malignancies, resulting in poor prognosis. The polyphenol (-)-epigallocatechin-3-gallate (EGCG), a major bioactive constituent of green tea, is beneficial in radiation-induced intestinal injury (RIII) alleviation. However, the bioavailability of EGCG in vivo is very low, with only 0.1% to 1.6% being absorbed into the intestine of mice. It is unclear whether gut microbial metabolites mediated by EGCG exert an effect to protect against radiation-induced intestinal injury. Male C57BL/6J mice were subjected to 13 Gy abdominal irradiation after EGCG gavage, and the severity of intestinal tissue damage was evaluated by HE staining, immunohistochemistry, and TUNEL assays. Fresh fecal samples were collected after the end of gavage, and then fecal sterile fecal filtrate (SFF) was obtained. Stool samples were collected 3 d after irradiation. The gut microbiome was detected by 16S rRNA sequencing, the metabolites were detected by GC‒MS analysis, and then the metabolites were applied to male C57BL/6J mice, observing and evaluating the severity of RIII. We first explored the effect of oral EGCG delivery on radiation-induced intestinal injury. Our results revealed that EGCG pre-supplementation prolongs survival time, prevents weight loss in mice and mitigates radiation-induced intestinal injury in irradiated mice. Using 16S rRNA gene-based microbiota analysis, we first found that EGCG ameliorated ionizing radiation-induced gut microbiota dysbiosis and enriched short-chain fatty acid (SCFA)-producing bacteria such as Roseburia, Ruminococcus, and Clostridia_UCG-014. In addition, metabolomic profiling analysis showed that the gut microbiota modulated EGCG-induced metabolic reprogramming in colonic tissues, particularly by enhancing galactose metabolism. Notably, EGCG supplementation resulted in the enrichment of the microbiota-derived galactose metabolism metabolite D-tagatose. Furthermore, exogenous treatment with D-tagatose reproduced similar protective effects as EGCG to protect against radiation-induced intestinal injury (RIII). D-tagatose restored the length of villi and improved the number of goblet cells, Ki-67-positive cells and Lgr5+ ISCs, while the number of TUNEL-positive cells in the intestinal tissues decreased significantly. To validate these discoveries, we performed fecal sterile fecal filtrate (SFF) from EGCG-dosed mice to untreated mice before ionizing radiation. SFF from EGCG-dosed mice alleviated the RIII over SFF from control mice superiorly. This study provides the first data indicating that oral EGCG ameliorated radiation-induced intestinal injury (RIII) by regulating the gut microbiota and metabolites. Our findings provide novel insights into D-tagatose derived by gut microbiota from EGCG-mediated remission of RIII.

Fabrication of egg white protein/phosphatidylcholine-EGCG co-assembled nanoparticles with sustained release in simulated gastrointestinal digestion and their transcellular permeability in Caco-2 cultures

Epigallocatechin-3-gallate (EGCG) is a kind of polyphenol with various biological activities but poor stability and bioavailability. The encapsulation of EGCG in a nano-delivery system effectively improves its shortcomings. In this research, co-assembled nanoparticles of egg white protein, phosphatidylcholine (PC), and EGCG (EW/PE1:5 NPs) were prepared by antisolvent precipitation to improve their bioavailability. The constructed EW/PE1:5 NPs had an average particle size of 172 nm, a ζ-potential of −26.1 mV, and a polymerization dispersion index (PDI) of 0.33. The encapsulation efficiency (EE) of EGCG was 88.09% and the loading capacity (LC) was 20.10%. UV spectra, FTIR, XRD and intermolecular force results indicated that hydrophobic, electrostatic and hydrogen bonding interactions contributed to the formation of EW/PE1:5 NPs. EW/PE1:5 NPs exhibited Fick diffusion and sustained release characteristics in simulated gastrointestinal digestion. In addition, the transcellular permeability of EW/PE1:5 NPs was significantly increased compared with free EGCG. At the same time, EW/PE1:5 NPs increased EGCG absorption transport and inhibited MRP2 and P-gp-mediated efflux transport. These results suggest that EW/PE1:5 NPs play a key role in improving the bioavailability of EGCG. Therefore, EW/PE1:5 NPs are expected to provide a theoretical basis for the design and development of functional foods or dietary supplements that synergistically enhance the bioavailability of EW, PC and other flavonoids.

Tea Polyphenol Coordinated with Nanoparticles of ZIF-8 and Coated with Polydopamine and PEG for Immuno-Oncotherapy

Epigallocatechin-3-gallate (EGCG), the most abundant tea polyphenol, possesses excellent anti-inflammation properties. Emerging studies proved its potent potential as an immune checkpoint (ICP) inhibitor for anticancer therapy. However, the low bioavailability of EGCG reduces its treatment efficiency. In this work EGCG-based nanomedicine EGCG–ZIF-8@PDA–PEG (EZP) was developed via the coordination between ZIF-8 MOF and EGCG, followed by polydopamine and PEG functionalization for efficient tumor-targeting EGCG delivery. Results demonstrated that the EGCG loading rate in EZP reached up to 85%. Both in vitro and in vivo studies proved that the EZP nanoparticles were capable of inhibiting the expression of ICP molecules and modulating the inflammatory tumor microenvironment, evidenced by the suppression of PD-L1 expression, the reduction of inflammatory cytokines, and the resultant decline in the number of immunosuppressive cells, for instance, myeloid-derived suppressor cells, tumor-associated macrophages, and regulatory T cells. These synergistic effects significantly improved the infiltration of dendritic cells and T cells in tumors, realizing an inspiring antitumor effect.

Chemical bonding of Epigallocatechin-3-gallate to the surface of nano-hydroxyapatite to enhance its biological activity for anti-osteosarcoma

Post-surgical defect repair combined with the elimination of residual cancer cells remains a major clinical challenge for the therapy of malignant bone tumors. As a natural product extracted from green tea, epigallocatechin-3-gallate (EGCG) has a wide range of biological activities. In this study, we investigated the anti-osteosarcoma and osteogenic potential of the natural compound EGCG in combination with hydroxyapatite (HA) for the post-operative treatment of osteosarcoma. We have synthesized well-dispersed surface amino-functionalized hydroxyapatite nanoparticles by the template method combined with surface modification techniques. Then, we conjugated EGCG with HA nanoparticles via amido linkage to prevent burst release of the biomolecules and improve their stability. The results showed that the as-prepared HA-EGCG nanoparticles had the same antioxidant activity as pure EGCG. The HA-EGCG nanoparticles demonstrated efficient EGCG release upon enzyme interactions in an acidic tumor environment, facilitating the accumulation of EGCG in tumor tissues and improving its bioavailability. Compared with pure EGCG and HA, HA-EGCG exhibited enhanced anticancer activity in vitro and in vivo. Furthermore, HA-EGCG could effectively promote osteogenic differentiation. This covalent strategy provides a simple method to fabricate a pH and enzyme-mediated delivery platform to refine the stability and bioavailability of EGCG. This research provides a strategy into designing biomaterials combined with EGCG for the potential application in bone diseases.

Stability of glycosylated complexes loaded with Epigallocatechin 3-gallate (EGCG)

The application of Epigallocatechin-3-gallate (EGCG) in food industry was limited by its low stability in aqueous solutions and poor bioavailability in vivo. The novel EGCG glycosylated arachin nanoparticles (Ara-CMCS-EGCG) and EGCG glycosylated casein nanoparticles (Cas-CMCS-EGCG) were prepared to improve the stability and bioavailability of EGCG. The effect of different variables on the storage stability and the slow-release behavior of novel glycosylation complexes in nanoparticle background solution and artificial gastrointestinal fluid were investigated. The results showed that the DPPH scavenging activity of Ara-CMCS-EGCG and Cas-CMCS-EGCG were stable in temperature (25 ∼ 70 °C). EGCG could enhance the crosslinking effect of molecular particles in glycosylation complexes solution. The glycosylated protein nanoparticles were stable to acid-base and enzymolysis in simulated gastrointestinal fluid. The release rate of EGCG in simulated intestinal fluid was higher than that in simulated gastric fluid. The glycosylated protein carrier can not only release EGCG slowly, but also significantly improve the stability and bioavailability of EGCG in simulated gastrointestinal fluid.

Bioaccessibility and Bioavailability of (-)-Epigallocatechin Gallate in the Bread Matrix with Glycemic Reduction.

Bread has a high glycemic index (GI) and rich contents of quickly digestible carbohydrates, which is associated with insulin resistance and the risk of chronic diseases. (-)-Epigallocatechin Gallate (EGCG) is the primary catechin component that inhibits starch hydrolases, while the low release and absorption rates limit its utilization. In this study, EGCG was added to the bread matrix for fortification to reduce its glycemic index compared to white bread. EGCG fortification at 4% decreased the starch digestion rate of baked bread by 24.43% compared to unfortified bread and by 14.31% compared to white bread, with an identical amount of EGCG outside the matrix. Moreover, the predicted GI (pGI) was reduced by 13.17% compared to white bread. Further, 4% EGCG-matched bread enhanced the bioaccessibility and bioavailability of EGCG by 40.38% and 47.11%, respectively, compared to the control. The results of molecular docking demonstrated that EGCG had a higher binding affinity with α-amylase than with α-glucosidase, indicating that EGCG may effectively inhibit the accumulation of carbs during starch digestion. Thus, EGCG can be used as a functional ingredient in bread to reduce its glycemic potential, and the bread matrix can be used as a carrier for EGCG delivery to enhance its bioaccessibility and bioavailability.

The interplays between epigallocatechin-3-gallate (EGCG) and Aspergillus niger RAF106 based on metabolism

Epigallocatechin-3-gallate (EGCG) is a vital kind of catechin with high bioactive activities, however, limited research has been conducted to elucidate the molecular basis of EGCG biotransformation by Aspergillus niger and the underlying regulatory mechanisms. In this study, A. niger RAF106, isolated from Pu-erh tea, was applied to conduct the EGCG fermentation process, and the samples were collected at different fermentation times to determine the intermediary metabolites of EGCG and the metabolome as well as physiological activity changes of A. niger RAF106. The results demonstrated that EGCG enhances the growth of A. niger RAF106 by promoting conidial germination and hyphae branching. Meanwhile, metabolomic analyses indicated that EGCG significantly regulates the amino acid metabolism of A. niger RAF106. Furthermore, metabolomic analyses also revealed that the levels of original secondary metabolites in the supernatant of the cultures changed significantly from the fermentation stage M2 to M3, in which the main differentially changed metabolites (DCMs) were flavonoids. Most of these flavonoids exhibited antioxidant properties and thus increased the radical scavenging activity of the supernatant of the cultures. In addition, we also found several intermediary metabolites of EGCG, GA, and EGC, including oolonghomobisflavan A, (−)-Epigallocatechin 3, 5-di-gallate, (−)-Epigallocatechin 3-(3-methyl-gallate) (−)-Catechin 3-O-gallate, 4′-Methyl-(−)-epigallocatechin 3-(4-methyl-gallate), myricetin, prodelphinidin B, 7-galloylcatechin, and 3-hydroxyphenylacetic acid. These findings contribute to improving the bioavailability of EGCG and help mine highly active metabolites, which can be used as raw materials for the development of pharmaceutical intermediates or functional foods. In addition, the results also provide a theoretical basis for better control of the risk of A. niger origin and the regulatory mechanisms of the biotransformation process mediated by A. niger.

Ameliorative effects of epigallocatechin-3-gallate nanoparticles on 2,4-dinitrochlorobenzene induced atopic dermatitis: A potential mechanism of inflammation-related necroptosis.

Atopic dermatitis (AD) is a common autoimmune and chronic inflammatory cutaneous disease with a relapsing-remitting course. Necroptosis is a regulated necrotic cell death mediated by receptor-interacting protein 1 (RIP1), receptor-interacting protein 3 (RIP3), and mixed lineage kinase domain-like pseudokinase (MLKL), which is activated by tumor necrosis factor-α (TNF-α). However, the mechanism and the role of necroptosis have not been delineated in AD progression. (-)-Epigallocatechin-3-gallate (EGCG), the main biological activity of tea catechin, is well known for its beneficial effects in the treatment of skin diseases. Here, PEG-PLGA-EGCG nanoparticles (EGCG-NPs) were formulated to investigate the bioavailability of EGCG to rescue cellular injury following the inhibition of necroptosis after AD. 2,4-dinitrochlorobenzene (DNCB) was used to establish AD mouse models. As expected, topically applied EGCG-NPs elicited a significant amelioration of AD symptoms in skin lesions, including reductions in the ear and skin thickness, dermatitis score, and scratching behavior, which was accompanied by redox homeostasis restored early in the experiment. In addition, EGCG-NPs significantly decreased the expression of inflammatory cytokines like TNF-α, interferon-γ (IFN-γ), interleukin-4 (IL-4), interleukin-6 (IL-6), and interleukin-17A (IL-17A) in a time-dependent manner than those of in AD group. As a result, the overexpression of RIP1, RIP3, and MLKL in the entire epidermis layers was dramatically blocked by EGCG-NPs, as well as the expression ofphosphorylated p38 (p-p38), extracellular signal-regulated kinase 1 (ERK1), and extracellular signal-regulated kinase 2 (ERK2). These findings promote that EGCG-NPs formulation represents a promising drug-delivery strategy for the treatment of AD by maintaining the balance of Th1/Th2 inflammation response and targeting necroptosis.

Epigallocatechin gallate: Phytochemistry, bioavailability, utilization challenges, and strategies.

Epigallocatechin gallate (EGCG), a green tea catechin, has gained the attention of current study due to its excellent health-promoting effects. It possesses anti-obesity, antimicrobial, anticancer, anti-inflammatory activities, and is under extensive investigation in functional foods for improvement. It is susceptible to lower stability, lesser bioavailability, and lower absorption rate due to various environmental, processing, formulations, and gastrointestinal conditions of the human body. Therefore, it is the foremost concern for the researchers to enhance its bioactivity and make it the most suitable therapeutic compound for its clinical applications. In the current review, factors affecting the bioavailability of EGCG and the possible strategies to overcome these issues are reviewed and discussed. This review summarizes structural modifications and delivery through nanoparticle-based approaches including nano-emulsions, encapsulations, and silica-based nanoparticles for effective use of EGCG in functional foods. Moreover, recent advances to enhance EGCG therapeutic efficacy by specifically targeting its molecules to increase its bioavailability and stability are also described. PRACTICAL APPLICATIONS: The main green tea constituent EGCG possesses several health-promoting effects making EGCG a potential therapeutic compound to cure ailments. However, its low stability and bioavailability render its uses in many disorders. Synthesizing EGCG prodrugs by structural modifications helps against its low bioavailability and stability by overcoming premature degradation and lower absorption rate. This review paper summarizes various strategies that benefit EGCG under different physiological conditions. The esterification, nanoparticle approaches, silica-based EGCG-NPs, and EGCG formulations serve as ideal EGCG modification strategies to deliver superior concentrations with lesser toxicity for its efficient penetration and absorption across cells both in vitro and in vivo. As a result of EGCG modifications, its bioactivities would be highly improved at lower doses. The protected or modified EGCG molecule would have enhanced potential effects and stability that would contribute to the clinical applications and expand its use in various food and cosmetic industries.

Research ArticleEnhanced Bioavailability of Epigallocatechin Gallate (EGCG) after Esterification and Complexation with Fish Oil

Research ArticleEnhanced Bioavailability of Epigallocatechin Gallate (EGCG) after Esterification and Complexation with Fish Oil

The chitosan/carboxymethyl cellulose/montmorillonite scaffolds incorporated with epigallocatechin-3-gallate-loaded chitosan microspheres for promoting osteogenesis of human umbilical cord-derived mesenchymal stem cell

Epigallocatechin-3-gallate (EGCG) is a plant-derived flavonoid compound with the ability to promote the differentiation of human bone marrow-derived mesenchymal stem cells (MSCs) into osteoblasts. However, the effect of EGCG on the osteogenic differentiation of the human umbilical cord-derived mesenchymal stem cells (HUMSCs) is rarely studied. Therefore, in this study, the osteogenic effects of EGCG are studied in the HUMSCs by detecting cell proliferation, alkaline phosphatase (ALP) activity, calcium deposition and the expression of relevant osteogenic markers. The results showed that EGCG can promote the proliferation and osteogenic differentiation of the HUMSCs in vitro at a concentration of 2.5–5.0 μM. Unfortunately, the EGCG is easily metabolized by cells during cell culture, which reduces its bioavailability. Therefore, in this paper, EGCG-loaded microspheres (ECM) were prepared and embedded in chitosan/carboxymethyl cellulose/montmorillonite (CS/CMC/MMT) scaffolds to form CS/CMC/MMT-ECM scaffolds for improving the bioavailability of EGCG. The HUMSCs were cultured on CS/CMC/MMT-ECM scaffolds to induce osteogenic differentiation. The results showed that the CS/CMC/MMT-ECM scaffold continuously released EGCG for up to 22 days. In addition, CS/CMC/MMT-ECM scaffolds can promote osteoblast differentiation. Taken together, the present study suggested that entrainment of ECM into CS/CMC/MMT scaffolds was a prospective scheme for promotion osteogenic differentiation of the HUMSCs.Graphical

Simple Approach to Enhance Green Tea Epigallocatechin Gallate Stability in Aqueous Solutions and Bioavailability: Experimental and Theoretical Characterizations

Because of its antioxidant, antimutagenic, and anti-infectious properties, epigallocatechin gallate (EGCG) is the most interesting compound among the green tea catechins polyphenols. However, its health effects are inconclusive due to its very low bioavailability, largely due to a particular instability that does not allow EGCG to reach the potency required for clinical developments. Over the last decade, many efforts have been made to improve the stability and bioavailability of EGCG using complex delivery systems such as nanotechnology, but these efforts have not been successful and easy to translate to industrial use. To meet the needs of a large-scale clinical trial requiring EGCG in a concentrated solution to anticipate swallowing impairments, we developed an EGCG-based aqueous solution in the simplest way while trying to circumvent EGCG instability. The solution was thoroughly characterized to sort out the unexpected stability outcome by combining experimental (HPLC-UV-mass spectrometry and infrared spectroscopy) and computational (density functional theory) studies. Against all odds, the EGCG–sucrose complex under certain conditions may have prevented EGCG from degradation in aqueous media. Indeed, in agreement with the ICH guidelines, the formulated solution was shown to be stable up to at least 24 months under 2–8 °C and at ambient temperature. Furthermore, considerable improvement in bioavailability in rats, against EGCG powder formulated in hard-gel capsules, was shown after gavage. Thus, the proposed formulation may provide an easily implementable platform to administer EGCG in the context of clinical development.

Co-encapsulation of (–)-epigallocatechin-3-gallate and quercetin in double emulsion hydrogel beads: Microstructures, functional properties, and digestion behaviors

Co-loaded (–)-epigallocatechin-3-gallate (EGCG) and quercetin double emulsions and hydrogel beads were prepared, and their structure, functions, and digestion characteristics were investigated. The double emulsion particles were adsorbed by the cross-linked chains of the hydrogel beads. The encapsulation efficiencies of EGCG and quercetin within the hydrogel beads were higher than those within the double emulsion, while the antioxidant activities of the double emulsions were higher than those of the hydrogel beads. A lower amount of free fatty acids (FFAs) was released from the hydrogel beads than that released from the double emulsions. The bioavailability of EGCG was higher in the hydrogel beads than those in the double emulsions, while the quercetin bioavailability was not significantly different expect for the ratio of 3:7. The hydrogel beads remained intact in the stomach; however, numerous oil spills occurred in the small intestine. These data may improve double-emulsion-based delivery systems for controlled lipolysis and the release of co-encapsulated hydrophilic and lipophilic bioactive compounds.

Bilosomes as effective delivery systems to improve the gastrointestinal stability and bioavailability of epigallocatechin gallate (EGCG)

Epigallocatechin gallate (EGCG) has a variety of biological activities, but exhibits poor stability and low bioavailability. In this study, EGCG bilosome was prepared and characterized, and its stability during different storage conditions (pH, NaCl concentration, and temperature) and in gastrointestinal fluid was evaluated and compared with liposomes and niosomes. Among them, EGCG niosomes had the highest pH stability, and the existence of sodium cholate reduced the stability of bilosomes in acidic medium. EGCG stability was significantly increased in the presence of salt ions (0–100 mM NaCl) and under different temperatures (25 °C, 37 °C) when delivered as niosomes and bilosomes. Retention rate of EGCG in bilosomes was 71.64 ± 4.05% after incubation in simulated intestinal fluid for 2 h, which was significantly higher than retention rate of EGCG liposomes (24.02 ± 3.95%) and niosomes (55.74 ± 6.85%), thus indicating greater gastrointestinal stability of EGCG bilosomes. Furthermore, bioavailability of EGCG encapsulated in bilosomes was improved by 1.98 times. Overall, these findings indicate that EGCG bilosomes, as a new delivery system, had great potential application as a means to improve stability and bioavailability of EGCG.

Epigallocatechin-3-Gallate Protects Pro-Acinar Epithelia Against Salivary Gland Radiation Injury.

Antioxidant agents are promising pharmaceuticals to prevent salivary gland (SG) epithelial injury from radiotherapy and their associated irreversible dry mouth symptoms. Epigallocatechin-3-gallate (EGCG) is a well-known antioxidant that can exert growth or inhibitory biological effects in normal or pathological tissues leading to disease prevention. The effects of EGCG in the various SG epithelial compartments are poorly understood during homeostasis and upon radiation (IR) injury. This study aims to: (1) determine whether EGCG can support epithelial proliferation during homeostasis; and (2) investigate what epithelial cells are protected by EGCG from IR injury. Ex vivo mouse SG were treated with EGCG from 7.5–30 µg/mL for up to 72 h. Next, SG epithelial branching morphogenesis was evaluated by bright-field microscopy, immunofluorescence, and gene expression arrays. To establish IR injury models, linear accelerator (LINAC) technologies were utilized, and radiation doses optimized. EGCG epithelial effects in these injury models were assessed using light, confocal and electron microscopy, the Griess assay, immunohistochemistry, and gene arrays. SG pretreated with EGCG 7.5 µg/mL promoted epithelial proliferation and the development of pro-acinar buds and ducts in regular homeostasis. Furthermore, EGCG increased the populations of epithelial progenitors in buds and ducts and pro-acinar cells, most probably due to its observed antioxidant activity after IR injury, which prevented epithelial apoptosis. Future studies will assess the potential for nanocarriers to increase the oral bioavailability of EGCG.

Therapeutic Potential of EGCG, a Green Tea Polyphenol, for Treatment of Coronavirus Diseases.

Epigallocatechin gallate (EGCG) is a major catechin found in green tea, and there is mounting evidence that EGCG is potentially useful for the treatment of coronavirus diseases, including coronavirus disease 2019 (COVID-19). Coronaviruses encode polyproteins that are cleaved by 3CL protease (the main protease) for maturation. Therefore, 3CL protease is regarded as the main target of antivirals against coronaviruses. EGCG is a major constituent of brewed green tea, and several studies have reported that EGCG inhibits the enzymatic activity of the coronavirus 3CL protease. Moreover, EGCG has been reported to regulate other potential targets, such as RNA-dependent RNA polymerase and the viral spike protein. Finally, recent studies have demonstrated that EGCG treatment interferes with the replication of coronavirus. In addition, the bioavailability of EGCG and future research prospects are discussed.

Sustained release of epigallocatechin-3-gallate from chitosan-based scaffolds to promote osteogenesis of mesenchymal stem cell

Epigallocatechin-3-gallate (EGCG) is a kind of flavonoids and has the ability to promote differentiation of mesenchymal stem cells (MSCs) into osteoblasts. However, the EGCG is easily metabolized by cells during cell culture, which reduces its bioavailability. Therefore, in this paper, EGCG-loaded chitosan nanoparticles (ECN) were fabricated and entrapped into chitosan/alginate (CS/Alg) scaffolds to form CS/Alg-ECN scaffolds for improving the bioavailability of EGCG. The human umbilical cord mesenchymal stem cells (HUMSCs) were cultured on CS/Alg-ECN scaffolds to induce osteogenic differentiation. The results indicated that the CS/Alg-ECN scaffolds continuously released EGCG for up to 16 days. Besides, these results suggested that CS/Alg-ECN scaffolds promoted osteoblast differentiation through activating Wnt/β-catenin signaling pathway. Collectively, this study demonstrated that the entrapment ECN into CS/Alg scaffolds was a promising strategy for promoting osteogenesis of MSCs.

Formulation and Optimization of Nanospanlastics for Improving the Bioavailability of Green Tea Epigallocatechin Gallate.

The present study aimed to investigate the potential of nanospanlastics for boosting the bioavailability of epigallocatechin gallate (EGCG). EGCG has valuable effects like anti-inflammation, anti-oxidation, and anti-tumorigenesis. Unfortunately, it has a low oral bioavailability due to its limited permeation and poor stability. To overcome these pitfalls, EGCG was fabricated as a nanospanlastic. Nanospanlastics are flexible nanovesicles that are composed of surfactants and edge activators (EAs). EAs improve the deformability of spanlastics by acting as a destabilizing factor of their vesicular membranes. EGCG-loaded spanlastics were prepared by an ethanol injection method, according to 23 factorial design, to explore the impact of different independent variables on entrapment efficiency (EE%), % drug released after 12 h (Q12h), and particle size (PS). In vitro characterization, ex vivo intestinal permeation test, and pharmacokinetic study of the optimized formula were performed. A newly developed RP-HPLC technique was adopted for the estimation of EGCG. The optimized formula (F4) demonstrated more prolonged drug release and a significant improvement in the EE%, permeability, deformability and stability than the corresponding niosomes. The pharmacokinetic study investigated that F4 had a more sustained drug release and a higher bioavailability than the conventional niosomes and free drugs. Nanospanlastics could be a promising approach for improving the bioavailability of EGCG.