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

Epigallocatechin gallate with nobiletin as a novel combination therapy to induce autophagy and apoptosis in oral cancer

Oral cancer (OC) represents a serious health and economic problem and the global prevalence of OC is still increasing. Epigallocatechin gallate (EGCG) is the most abundant polyphenol in green tea, and nobiletin (NOB) is a bioactive polyethoxylated flavone isolated from the peels of citrus fruits. Both have been proven to exert an anti-cancer effect in OC. Integrated stress response (ISR) is a key translation signaling network activated by oncogenic stress, modulating ISR activity is an innovative drug target in cancer therapy. Herein, we investigated combined EGCG and NOB in a ratio at 125 μM:25 μM additively decreased cell viability of OC cells most. Combination treatment with 125 μM EGCG and 25 μM NOB increased LC3 expression and autophagosome formation, and induced autophagic cell death. In addition, this combination increased cleaved caspase-3, cleaved caspase-9, and cleaved PARP levels, induced apoptotic cell death. Furthermore, we explored the effect of the EGCG and NOB combination in regulating ISR activity. Our results showed that this combination inhibited the GCN2/eIF2α axis and activated the PERK/ATF4/CHOP pathway. Results further demonstrated that silencing either GCN2 or PERK reversed EGCG+NOB-induced cell proliferation inhibition, autophagy and apoptosis. In this combined system, GCN2 and PERK are targets of EGCG-induced autophagy and NOB-induced apoptosis, EGCG and NOB produce additive effects to induce OC cell death. In summary, our study identified that EGCG combined with NOB, as a potent ISR mediator, cooperates to induce autophagy and apoptosis, further supporting the combination of EGCG and NOB as a promising strategy for OC treatment.

Nano-Engineered Epigallocatechin Gallate (EGCG) Delivery Systems: Overcoming Bioavailability Barriers to Unlock Clinical Potential in Cancer Therapy

Epigallocatechin gallate (EGCG), a bioactive polyphenol derived from Camellia sinensis, exhibits multimodal anticancer activity through mechanisms such as apoptosis induction, metastasis suppression, and chemoresistance reversal. Despite its therapeutic promise, clinical application is constrained by rapid metabolism, poor bioavailability, and inconsistent biodistribution. Recent advances in nanotechnology have enabled the development of innovative delivery systems including pH-responsive nanoparticles, lipid-polymer hybrids, and ligand-functionalized carriers that enhance EGCG stability, tumor targeting, and bioavailability by 3- to fivefold in preclinical models. These platforms also facilitate synergistic co-delivery with chemotherapeutics like doxorubicin, amplifying cytotoxicity and overcoming multidrug resistance. Mechanistically, EGCG modulates oncogenic pathways via NF-κB suppression, caspase activation, and MMP-9 downregulation, demonstrating efficacy across diverse cancer types. However, translational challenges persist, such as nanoparticle toxicity, variable tumor accumulation, and insufficient penetration in hypoxic microenvironments. Regulatory hurdles, including the lack of harmonized global standards for herbal medicinal products, further complicate clinical adoption. To bridge these gaps, future research must prioritize scalable cGMP-compliant manufacturing, rigorous preclinical toxicity profiling, and robust clinical trials to validate safety and efficacy. Addressing these issues could position nanoengineered EGCG as a paradigm-shifting therapy in precision oncology, aligning with ESCOP's mission to integrate evidence-based phytomedicines into conventional cancer care. This review underscores the necessity of interdisciplinary collaboration to standardize phytopreparations, refine regulatory frameworks, and advance biomarker-driven clinical validation, ultimately unlocking the full potential of EGCG in modern therapeutics.

Lipid-based nano-carriers for the delivery of anti-obesity natural compounds: advances in targeted delivery and precision therapeutics

Obesity is a major global health challenge, contributing to metabolic disorders such as type 2 diabetes, cardiovascular diseases, and hypertension. The increasing prevalence of obesity, driven by sedentary lifestyles, poor dietary habits, and genetic predisposition, underscores the urgent need for effective therapeutic strategies. Conventional pharmacological treatments, including appetite suppressants and metabolic modulators, often fail to provide sustainable weight loss due to side effects, poor adherence, and limited long-term efficacy. As a result, natural bioactive compounds have gained attention for their anti-obesity potential. However, their clinical application is hindered by poor bioavailability, rapid metabolism, and inefficient delivery. Lipid-based nano-carriers, including liposomes, solid lipid nanoparticles, and nanostructured lipid carriers, offer a promising solution by enhancing the solubility, stability, and targeted delivery of these compounds. These advanced delivery systems improve bioactive retention, enable controlled release, and enhance therapeutic action on adipose tissue and metabolic pathways. Additionally, functionalized and stimulus-responsive nanocarriers present innovative approaches for precision obesity treatment. Despite these advancements, challenges remain in large-scale production, regulatory approval, and long-term safety. Overcoming these barriers is critical to ensuring the successful clinical translation of nano-formulated therapies. This review explores the potential of lipid-based nano-carriers in optimizing the therapeutic efficacy of natural anti-obesity compounds and highlights their role in advancing next-generation obesity management strategies.

Magnesium-gallate MOF integrated conductive cryogel for inflammation regulation and boosting bone regeneration

The regeneration and repair of natural bone is a complex and multifaceted process. Potentially, multifunctional scaffolds that exhibit synergistic effects of various biological activities and align with the dynamic bone healing process, are highly expected to achieve desirable bone repairing outcomes. Bioavailable magnesium (Mg) is an essential element taking part in bone regeneration via promoting angiogenesis and osteogenesis. Polyphenol gallic acid (GA) is an anti-inflammatory molecule that can modulate immune microenvironment. To control their release behaviors, Mg2+ and GA can react with each other to form metal-organic frameworks (MOF), which are then embedded into conductive porous scaffolds made of gelatin cryogel and poly(3,4-ethyldioxyethiophene): polystyrene sulfonate (PEDOT:PSS). In in vitro cell culture, the MOF-integrated conductive scaffold can simultaneously provide sustained supply of Mg2+ and GA to modulate the biological responses of a variety of cells. In in vivo evaluations, it shows remarkably enhanced new bone formation, as compared to groups of only MOF-contained non-conductive scaffold or conductive scaffold without MOF in rat calvarial defect model. In summary, conductive scaffold associated with sustained release of bioactive factors can serve as an effective treatment for inducing neo-bone growth benefiting from the synergistical contributions of diverse bioactive factors.

Updated Review on Natural Polyphenols: Molecular Mechanisms, Biological Effects, and Clinical Applications for Cancer Management

Polyphenols, naturally occurring compounds found exclusively in plants, have gained significant attention for their potential in cancer prevention and treatment. These compounds are known for their antioxidant properties and are abundant in various plant-based foods, such as vegetables, fruits, grains, and beverages. Recent studies have highlighted the broad spectrum of health benefits of polyphenols, including their antiviral, anti-inflammatory, and anticancer properties. In addition, these naturally derived compounds are increasingly important for drug discovery due to their high molecular diversity and novel biofunctionalities. This review provides an in-depth analysis of the current research and knowledge on the potential use of dietary polyphenols as bioactive compounds for the prevention and treatment of various cancers. This review aims to provide valuable insights into the mechanisms underlying the anticancer properties of phenolic compounds in both laboratory and clinical settings. Furthermore, this review highlights the positive clinical outcomes associated with the use of polyphenols as anticancer agents and offers guidance for future research to advance this promising field.

Unlocking the Therapeutic Potential of Natural Polyphenols in Esophageal Cancer

OPINION STATEMENT

Esophageal cancer (EC), one highly malignant upper gastrointestinal cancer, is the eighth most commonly occurring cancer and the sixth leading cause of cancer-related deaths worldwide. Clinically, this malignancy is considered to be one of the most difficult-to-treat cancers, owing to its resistance to common therapies like chemotherapy and radiotherapy, and few targeted therapies are available. There is currently an unmet need for treatment of EC. Polyphenols are naturally occurring plant secondary metabolites in response to environmental threats and injury. Epidemiological evidence suggests that long-term consumption of a polyphenol-rich diet is inversely associated with the risk of cancer. Currently, natural polyphenols have received increased attention for their potential therapeutic effects on EC. In this review, we summarize and discuss recent progress in the therapeutic potential of natural polyphenols in EC, as well as their sources, oral bioavailability, and pharmacokinetics. We review natural polyphenols combined with approved chemotherapy and radiotherapy to overcome challenges faced by either monotherapy. We also discuss the current challenges and future directions to accelerate the clinical application of natural polyphenols in EC. We concluded that natural polyphenols represent promising candidates for the management of EC. Well-designed randomized controlled studies are warranted to verify the efficacy and safety of natural polyphenols for EC. Knowledge gained from this review will outline possible future research directions and should help to develop new therapeutics for this disease.

The Antiviral Activity of Polyphenols

Polyphenols are secondary metabolites produced by a large variety of plants. These compounds that comprise the class of phenolic acids, stilbenes, lignans, coumarins, flavonoids, and tannins have a wide range of employment, from food production to medical usages. Among the beneficial applications of polyphenols, their antiviral activity is gaining importance due to the increased prevalence of drug-resistant viruses such as herpes and hepatitis B viruses. In the present review, we provide an overview of the most promising or commonly used antiviral polyphenols and their mechanisms of action focusing on their effects on enveloped viruses of clinical importance (double-stranded linear or partially double-stranded circular DNA viruses, negative sense single-stranded RNA viruses with nonsegmented or segmented genomes, and positive sense single-stranded RNA viruses). The present work emphasizes the relevance of polyphenols, in particular epigallocatechin-3-gallate and resveratrol, as alternative or supportive antivirals. Polyphenols could interfere with virtually all steps of viral infection, from the adsorption to the release of viral particles. The activity of polyphenols against viruses is especially relevant given the risk of widespread outbreaks associated with viruses, remarked by the recent COVID-19 pandemic.

Research Progress on the Protective Effect of Green Tea Polyphenol (-)-Epigallocatechin-3-Gallate (EGCG) on the Liver

The liver, as the primary metabolic organ, is susceptible to an array of factors that can harm liver cells and give rise to different liver diseases. Epigallocatechin gallate (EGCG), a natural compound found in green tea, exerts numerous beneficial effects on the human body. Notably, EGCG displays antioxidative, antibacterial, antiviral, anti-inflammatory, and anti-tumor properties. This review specifically highlights the pivotal role of EGCG in liver-related diseases, focusing on viral hepatitis, autoimmune hepatitis, fatty liver disease, and hepatocellular carcinoma. EGCG not only inhibits the entry and replication of hepatitis B and C viruses within hepatocytes, but also mitigates hepatocytic damage caused by hepatitis-induced inflammation. Furthermore, EGCG exhibits significant therapeutic potential against hepatocellular carcinoma. Combinatorial use of EGCG and anti-hepatocellular carcinoma drugs enhances the sensitivity of drug-resistant cancer cells to chemotherapeutic agents, leading to improved therapeutic outcomes. Thus, the combination of EGCG and anti-hepatocellular carcinoma drugs holds promise as an effective approach for treating drug-resistant hepatocellular carcinoma. In conclusion, EGCG possesses hepatoprotective properties against various forms of liver damage and emerges as a potential drug candidate for liver diseases.

Berberine-inspired ionizable lipid for self-structure stabilization and brain targeting delivery of nucleic acid therapeutics

Lipid nanoparticles have shown success in targeting major organs such as the liver, spleen, and lungs, but crossing the blood-brain barrier (BBB) remains a major challenge. Effective brain-targeted delivery systems are essential for advancing gene therapy for neurological diseases but remain limited by low transport efficiency and poor nucleic acid stability. Here, we report a library of ionizable lipids based on the tetrahydroisoquinoline structure of protoberberine alkaloids, designed to improve BBB penetration via dopamine D3 receptor-mediated endocytosis. These nanoparticles offer three key advantages: enhanced brain uptake, improved nucleic acid stability through poly(A) self-assembly, and minimal immunogenicity with inherent neuroprotective properties. In murine models, they demonstrate therapeutic potential in Alzheimer's disease, glioma, and cryptococcal meningitis. This berberine-inspired delivery system integrates precise receptor targeting with nucleic acid stabilization, offering a promising platform for brain-targeted therapeutics.

Production of protein-epigallocatechin gallate conjugates using free radicals induced by ultrasound and their gelation behavior

In this study, free radicals generated by ultrasound were used to prepare conjugates of food proteins (soybean protein isolates, sodium caseinate and gelatin) with epigallocatechin gallate (EGCG). The changes in free amino and sulfhydryl group contents were used to confirm the occurrence of conjugation. The formation of covalent interactions on surface hydrophobicity, functional groups, structures, thermal stability, and gelation behavior of three proteins were investigated. The results showed that conjugation led to decrease in free amino and sulfhydryl group contents, reduction in the intensity of amide A and fluorescence intensity, and increase in β-fold content. The conjugation also resulted in a decrease in surface hydrophobicity and thermal stability of soybean protein isolates and sodium caseinate, but an increase in the surface hydrophobicity and thermal stability of gelatin. Furthermore, the covalent bonding between proteins and EGCG improved gel strength, water holding capacity, and resulted in a denser and more compact microstructure.

Green Tea Polyphenol Epigallocatechin Gallate Interactions with Copper-Serum Albumin

Epigallocatechin gallate (EGCg), an abundant phytochemical in green tea, is an antioxidant that also binds proteins and complex metals. After gastrointestinal absorption, EGCg binds to serum albumin in the hydrophobic pocket between domains IIA and IIIA and overlaps with the Sudlow I site. Serum albumin also has two metal binding sites, a high-affinity N-terminal site (NTS) site that selectively binds Cu(II), and a low-affinity, less selective multi-metal binding site (MBS). We proposed to determine whether EGCg binds or reacts with Cu(II)-serum albumin using fluorescence, UV-Visible and electron paramagnetic resonance (EPR) spectroscopy. Our results suggest that when serum albumin is loaded with Cu(II) in both sites, EGCg binds to the MBS-Cu(II) and reduces the copper to Cu(I). EGCg does not bind to or react with Cu(II) in the high-affinity NTS site. Potential consequences include changes in copper homeostasis and damage from pro-oxidative Fenton reactions.

Curcumin and its Analogues in Oral Squamous Cell Carcinoma: State-of-the-art and Therapeutic Potential

Oral Squamous Cell Carcinoma (OSCC) is the most common cancer arising from squamous epithelium in the oral cavity and is characterized by high aggressiveness and metastatic potential, which together with a late diagnosis results in a 5-year survival rate of only 50% of patients. The therapeutic options for OSCC management are limited and largely influenced by the cancer stage. While radical surgery can be curative in early stage of disease, most cases require adjuvant therapies, including chemotherapy and radiotherapy which, however, often achieve poor curative rates and are associated with important negative effects. Therefore, there is an urgent need to discover new alternative treatment strategies to improve patients' outcomes. Several medicinal herbs are being studied for their preventive or therapeutic effect in several diseases, including cancer. In particular, the Indian spice curcumin, largely used in oriental countries, has been studied as a chemopreventive or adjuvant agent for different malignancies. Indeed, curcumin is characterized by important biological properties, including antioxidant, anti-inflammatory, and anticancer effects, which could also be exploited in OSCC. However, due to its limited bioavailability and poor aqueous solubility, this review is focused on studies designing new synthetic analogues and developing novel types of curcumin delivery systems to improve its pharmacokinetic and biological properties. Thus, this review analyses the potential therapeutic role of curcumin in OSCC by providing an overview of current in vitro and in vivo studies demonstrating the beneficial effects of curcumin and its analogues in OSCC.

Epigallocatechin-3-gallate therapeutic potential in human diseases: molecular mechanisms and clinical studies

Green tea has garnered increasing attention across age groups due to its numerous health benefits, largely attributed to Epigallocatechin 3-gallate (EGCG), its key polyphenol. EGCG exhibits a wide spectrum of biological activities, including antioxidant, anti-inflammatory, antibacterial, anticancer, and neuroprotective properties, as well as benefits for cardiovascular and oral health. This review provides a comprehensive overview of recent findings on the therapeutic potential of EGCG in various human diseases. Neuroprotective effects of EGCG include safeguarding neurons from damage and enhancing cognitive function, primarily through its antioxidant capacity to reduce reactive oxygen species (ROS) generated during physiological stress. Additionally, EGCG modulates key signaling pathways such as JAK/STAT, Delta-Notch, and TNF, all of which play critical roles in neuronal survival, growth, and function. Furthermore, EGCG is involved in regulating apoptosis and cell cycle progression, making it a promising candidate for the treatment of metabolic diseases, including cancer and diabetes. Despite its promising therapeutic potential, further clinical trials are essential to validate the efficacy and safety of EGCG and to optimize its delivery to target tissues. While many reviews have addressed the anticancer properties of EGCG, this review focuses on the molecular mechanisms and signaling pathways by which EGCG used in specific human diseases, particularly cancer, neurodegenerative and metabolic diseases. It serves as a valuable resource for researchers, clinicians, and healthcare professionals, revealing the potential of EGCG in managing neurodegenerative disorders, cancer, and metabolic diseases and highlighting its broader therapeutic values.

Biophysical characterization and in silico analysis of natural and synthetic compounds targeting Listeria monocytogenes HtrA protease

HtrA protein is a member of a serine protease family with dual functions as a protease and molecular chaperone. It is a virulence factor in many bacteria, including the food-borne pathogen Listeria monocytogenes (Lm), which induces listeriosis in humans. Hence, inhibitors of LmHtrA protease have great importance in the control of infection. Many natural compounds have been used in the inhibition studies of proteases; here, we have performed the inhibition studies of LmHtrA with 31 compounds from different origins. The spectrophotometric assays revealed that plant compounds are promising inhibitors of LmHtrA protease activity compared to other tested peptides and synthetic compounds. The green tea catechin, EGCG has been identified as an inhibitor of protease activity of LmHtrA with a low IC50 value of 0.754 ± 0.2 μM. The substrate cleavage analysis by SDS-PAGE and SPR experiments corroborates the spectrophotometric results by exhibiting protease inhibition and showing the micromolar affinity of EGCG with LmHtrA, respectively. The interaction between rLmHtrA and EGCG was investigated by fluorescence spectroscopy. The binding constant and the number of binding sites were determined as 1.86 × 10(5) M(-1) and 1.2, respectively. The molecular docking and dynamics results of LmHtrA-inhibitor complexes have provided new insights into the inhibition mechanism of LmHtrA compared with other serine proteases. The findings of this study may open up new avenues for the development of natural compound-based derivatives of LmHtrA inhibitors that might be more potent and less harmful to humans.

Metal-phenolic nanoparticles enhance low temperature photothermal therapy for bacterial biofilm in superficial infections

Bacterial infections, especially induced by multidrug-resistant pathogens, have become a significant global health concern. In the infected tissues, biofilms not only serve as a source of nutrients but also act as protective barriers that impede antibiotic penetration. Herein, we developed tea polyphenols epigallocatechin gallate (EGCG) Au nanoparticles (E-Au NPs) through direct one-step self-assembly methods by EGCG chelating with Au ions to eradicate antibiotic-resistant bacteria methicillin-resistant Staphylococcus aureus (MRSA) and prevent the formation of biofilm under near-infrared (NIR) irradiation. The outstanding antibacterial effect involved in mild photothermal therapy, reactive oxygen species production, pathogenicity-related genes regulation, and quinoprotein formation that were specific to the polyphenol-based NPs. The excellent antibacterial and anti-inflammatory therapeutic efficacy of E-Au NPs was validated and topically applied in murine MRSA-infected skin wounds and keratitis model in vivo to kill bacteria, reduce the inflammation response and promote wound healing. Furthermore, the ophthalmic and systemic biosafety profiles were thoroughly evaluated while no significant side effects were revealed achieving a balance between high-efficiency antibacterial properties and biocompatibility. This study provides an effective therapeutic agent of metal-phenolic materials for superficial tissue infection with favorable prognosis and potential in clinical translation.

Chinese medicine in the treatment of chronic hepatitis B: The mechanisms of signal pathway regulation

Chronic hepatitis B (CHB) is a chronic inflammatory disease of the liver caused by infection with the hepatitis B virus (HBV), which in later stages can lead to the development of end-stage liver diseases such as cirrhosis and hepatocellular carcinoma in severe cases, jeopardizing long-term quality of life, with a poor prognosis, and placing a serious financial burden on many families around the world. The pathogenesis of the disease is complex and closely related to the immune function of the body, which has not yet been fully elucidated. The development of chronic hepatitis B is closely related to the involvement of various signaling pathways, such as JAK/STAT, PI3K/Akt, Toll-like receptor, NF-κB and MAPK signaling pathways. A large number of studies have shown that Chinese medicine has obvious advantages in anti-hepatitis B virus, and it can effectively treat the disease by modulating relevant signaling pathways, strengthening immune resistance and defense, and inhibiting inflammatory responses, and certain research progress has been made, but there is still a lack of a comprehensive review on the modulation of relevant signaling pathways in Chinese medicine for the treatment of CHB. Therefore, this article systematically combed and elaborated the relevant literature on the modulation of relevant signaling pathways by traditional Chinese medicine in recent years, with a view to providing new ideas for the treatment of CHB and further drug development.

Harnessing the Power of Fermented Tea to Improve Gut Microbiota and Combat Obesity Epidemic

The global rise in obesity rates has prompted a thorough evaluation of dietary strategies that may alleviate this metabolic issue. Fermented tea, a beverage rich in polyphenols and catechins, has emerged as a viable therapeutic option for obesity management. This review discusses the role of fermented tea in modulating the gut microbiome, a critical factor in energy regulation and obesity. We explore how the bioactive components in fermented tea influence gut health and their implications for metabolic health. Fermented tea may inhibit weight gain and fat accumulation in obese animal models, likely by promoting beneficial bacteria and suppressing harmful species. Changes in the production of short-chain fatty acids and improvements in gut barrier integrity are linked to enhanced insulin sensitivity and reduced inflammatory markers, essential for effective obesity management. However, barriers remain in applying these findings in clinical settings, such as the need for standardized fermentation techniques and accurate dosage assessments. This review underscores the therapeutic potential of fermented tea in obesity treatment and advocates for further research to enhance its integration with public health initiatives.

Neurodegenerative diseases and catechins: (-)-epigallocatechin-3-gallate is a modulator of chronic neuroinflammation and oxidative stress

Catechins, a class of phytochemicals found in various fruits and tea leaves, have garnered attention for their diverse health-promoting properties, including their potential in combating neurodegenerative diseases. Among these catechins, (-)-epigallocatechin-3-gallate (EGCG), the most abundant polyphenol in green tea, has emerged as a promising therapeutic agent due to its potent antioxidant and anti-inflammatory effects. Chronic neuroinflammation and oxidative stress are key pathological mechanisms in neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD). EGCG has neuroprotective efficacy due to scavenging free radicals, reducing oxidative stress and attenuating neuroinflammatory processes. This review discusses the molecular mechanisms of EGCG's anti-oxidative stress and chronic neuroinflammation, emphasizing its effects on autoimmune responses, neuroimmune system interactions, and focusing on the related effects on AD and PD. By elucidating EGCG's mechanisms of action and its impact on neurodegenerative processes, this review underscores the potential of EGCG as a therapeutic intervention for AD, PD, and possibly other neurodegenerative diseases. Overall, EGCG emerges as a promising natural compound for combating chronic neuroinflammation and oxidative stress, offering novel avenues for neuroprotective strategies in the treatment of neurodegenerative disorders.

Possibility and challenge of plant-derived ferritin cages encapsulated polyphenols in the precise nutrition field

Polyphenols have attracted extensive attention due to their rich functional activities, such as antioxidant, anti-inflammatory and anti-tumor. However, the low solubility and poor stability limit their bioavailability and functional activities. Plant-derived ferritin cages have a unique hollow cage structure that can embed polyphenols to improve their unfavorable properties. Therefore, it is essential to adequately elaborate and summarize plant-derived ferritin cages to maximize their potential benefits in nutritional interventions. This review focuses on the fundamental properties of plant-derived ferritin cages, including the preparation process, purification technology, identification methods, and structural and functional properties. The relevant research on ferritin cages in polyphenol delivery has been summarized, including the delivery of water/lipid soluble polyphenols, modification of ferritin cages, and the interaction between polyphenols and ferritin cages. The research progress, shortcomings and prospects of plant-derived ferritin cages in precise nutrition are introduced. In addition, the relevant research on ferritin in immune response and protein engineering is also discussed to provide the theoretical basis for applying plant-derived ferritin cages in many frontier fields.

Effects of Green Tea Extract Epigallocatechin-3-Gallate on Oral Diseases: A Narrative Review

OBJECTIVES

Oral diseases are among the most prevalent diseases globally. Accumulating new evidence suggests considerable benefits of epigallocatechin-3-gallate (EGCG) for oral health. This review aims to explore the role and application of EGCG in main oral diseases.

METHODS

This narrative review thoroughly examines and summarizes the most recent literature available in scientific databases (PubMed, Web of Science, Scopus, and Google Scholar) reporting advances in the role and application of EGCG within the dental field. The major keywords used included "EGCG", "green tea extract", "oral health", "caries", "pulpitis", "periapical disease", "periodontal disease", "oral mucosa", "salivary gland", and "oral cancer".

CONCLUSIONS

EGCG prevents and manages various oral diseases through its antibacterial, anti-inflammatory, antioxidant, and antitumor properties. Compared to traditional treatments, EGCG generally exhibits lower tissue irritation and positive synergistic effects when combined with other therapies. Novel delivery systems or chemical modifications can significantly enhance EGCG's bioavailability, prolong its action, and reduce toxicity, which are current hotspots in developing new materials.

CLINICAL SIGNIFICANCE

this review provides an exhaustive overview of the biological activities of EGCG to major oral diseases, alongside an exploration of applications and limitations, which serves as a reference for preventing and managing oral ailments.

Plasma Gel Matrix as a Promising Carrier of Epigallocatechin Gallate for Regenerative Medicine

Plasma gel (PG) is a protein matrix prepared from platelet-poor plasma and can be utilized as a drug carrier for controlled release. We previously demonstrated its applicability as a carrier of polyphosphate. Epigallocatechin-3-gallate (EGCG) is the main flavonoid found in green tea and functions as a strong antioxidant. To explore the applicability of PG as an EGCG carrier, we examined the release of EGCG from the PG matrix using an in vitro system. Pooled platelet-poor plasma (PPP) was prepared from four healthy adult male donors, mixed with EGCG, and heated at 75 °C for 10 or 20 min to prepare the PG matrix. The PG-EGCG matrix was incubated in PBS at 37 °C, and the EGCG released into PBS was determined using spectrophotometry. The antioxidant capacity was determined based on the principle of the iodine decolorization reaction. EGCG precipitated and incorporated into the PG matrix during thermal preparation. Trypsin, used to simulate the in vivo degradation of PG, released EGCG from the PG matrix over time. The released EGCG maintained its antioxidant capacity during incubation. These results indicate that thermally prepared PG matrices can be utilized as a promising EGCG carrier in the fields of tissue engineering and regenerative medicine.

pH-Sensitive Nanoparticles of Epigallocatechin-3-Gallate in Enhanced Colorectal Cancer Therapy

AIM

Encapsulating epigallocatechin-3-gallate (EGCG) in pH-sensitive polymeric nanoparticles for targeted delivery of drugs could revolutionize colorectal cancer treatment.

MATERIALS & METHODS

Nanoparticles were synthesized to release drugs at colon pH. Dynamic light scattering measured their average diameter and ζ-potential, while differential scanning calorimetry and x-ray diffraction assessed EGCG encapsulation.

RESULTS

The nanoparticles showed stability and bioavailability in the gastrointestinal tract, efficiently encapsulating and releasing over 93% of EGCG at pH 7.2. They enhanced cytotoxicity against HT-29 cells and demonstrated antibacterial properties, increasing apoptosis and cell cycle arrest.

CONCLUSION

The study underscores the potential of nanoparticles in enhancing EGCG delivery for colorectal cancer therapy, aiming to minimize side effects and improve therapeutic outcomes.

4″-Alkyl EGCG Derivatives Induce Cytoprotective Autophagy Response by Inhibiting EGFR in Glioblastoma Cells

Epidermal growth factor receptor (EGFR)-targeted therapy has been proven vital in the last two decades for the treatment of multiple cancer types, including nonsmall cell lung cancer, glioblastoma, breast cancer and head and neck squamous cell carcinoma. Unfortunately, the majority of approved EGFR inhibitors fall into the drug resistance category because of continuous mutations and acquired resistance. Recently, autophagy has surfaced as one of the emerging underlying mechanisms behind resistance to EGFR-tyrosine kinase inhibitors (TKIs). Previously, we developed a series of 4″-alkyl EGCG (4″-Cn EGCG, n = 6, 8, 10, 12, 14, 16, and 18) derivatives with enhanced anticancer effects and stability. Therefore, the current study hypothesized that 4″-alkyl EGCG might induce cytoprotective autophagy upon EGFR inhibition, and inhibition of autophagy may lead to improved cytotoxicity. In this study, we have observed growth inhibition and caspase-3-dependent apoptosis in 4″-alkyl EGCG derivative-treated glioblastoma cells (U87-MG). We also confirmed that 4″-alkyl EGCG could inhibit EGFR in the cells, as well as mutant L858R/T790M EGFR, through an in vitro kinase assay. Furthermore, we have found that EGFR inhibition with 4″-alkyl EGCG induces cytoprotective autophagic responses, accompanied by the blockage of the AKT/mTOR signaling pathway. In addition, cytotoxicity caused by 4″-C10 EGCG, 4″-C12 EGCG, and 4″-C14 EGCG was significantly increased after the inhibition of autophagy by the pharmacological inhibitor chloroquine. These findings enhance our understanding of the autophagic response toward EGFR inhibitors in glioblastoma cells and suggest a potent combinatorial strategy to increase the therapeutic effectiveness of EGFR-TKIs.

Leucettinib-21, a DYRK1A Kinase Inhibitor as Clinical Drug Candidate for Alzheimer's Disease and Down Syndrome

Alzheimer's disease (AD) and Down syndrome (DS) share a common therapeutic target, the dual-specificity, tyrosine phosphorylation activated kinase 1A (DYRK1A). Abnormally active DYRK1A is responsible for cognitive disorders (memory, learning, spatial localization) observed in both conditions. In DS, DYRK1A is overexpressed due to the presence of the DYRK1A gene on chromosome 21. In AD, calcium-activated calpains cleave full-length DYRK1A (FL-DYRK1A) into a more stable and more active, low molecular weight, kinase (LMW-DYRK1A). Genetic and pharmacological experiments carried out with animal models of AD and DS strongly support the idea that pharmacological inhibitors of DYRK1A might be able to correct memory/learning disorders in people with AD and DS. Starting from a marine sponge natural product, Leucettamine B, Perha Pharmaceuticals has optimized, through classical medicinal chemistry, and extensively characterized a small molecule drug candidate, Leucettinib-21. Regulatory preclinical safety studies in rats and minipigs have been completed and formulation of Leucettinib-21 has been optimized as immediate-release tablets. Leucettinib-21 is now undergoing a phase 1 clinical trial (120 participants, including 12 adults with DS and 12 patients with AD). The therapeutic potential of DYRK1A inhibitors in AD and DS is presented.