Therapeutic Effects of Green Tea Polyphenol (‒)-Epigallocatechin-3-Gallate (EGCG) in Relation to Molecular Pathways Controlling Inflammation, Oxidative Stress, and Apoptosis

Epigallocatechin-3-gallate attenuates fluoride induced apoptosis via PI3K/FoxO1 pathway in ameloblast-like cells

Fluoride is a double-edged sword. It was widely used for early caries prevention while excessive intake caused a toxicology effect, affected enamel development, and resulted in dental fluorosis. The study aimed to evaluate the protective effect and mechanism of Epigallocatechin-3-gallate (EGCG) on the apoptosis induced by fluoride in ameloblast-like cells. We observed that NaF triggered apoptotic alterations in cell morphology, excessive NaF arrested cell cycle at the G1, and induced apoptosis by up-regulating Bax and down-regulating Bcl-2. NaF activated the insulin-like growth factor receptor (IGFR), and phosphatidylinositol-3-hydroxylase (p-PI3K), while dose-dependently down-regulating the expression of Forkhead box O1 (FoxO1). EGCG supplements reversed the changes in LS8 morphology, the cell cycle, and apoptosis induced by fluoride. These results indicated that EGCG possesses a protective effect against fluoride toxicity. Furthermore, EGCG suppressed the activation of p-PI3K and the down-regulation of FoxO1 caused by fluoride. Collectively, our findings suggested that EGCG attenuated fluoride-induced apoptosis by inhibiting the PI3K/FoxO1 signaling pathway. EGCG may serve as a new alternative method for dental fluorosis prevention, control, and treatment.

Oligomerization mechanism of epigallocatechin-3-O-gallate during autoxidation

The autoxidation of tea catechins by dissolved oxygen proceeds in pH-neutral aqueous solutions, and the major products are oligomers. However, the reaction mechanisms have not been clarified. In this study, the autoxidation of (-)-epigallocatechin-3-O-gallate (1) was examined. The autoxidation with β-cyclodextrin, which includes the A-ring of 1, significantly suppressed oligomer production and increased the formation of products generated by the oxidative cleavage of the B-ring, indicating the participation of the A-ring in the oligomerization. Further, the autoxidation of 1 in the presence of phloroglucinol, a mimic of the catechin A-ring, yielded products via the nucleophilic addition of phloroglucinol to the B-ring quinone of 1. These results indicated that the oxidative A-B ring couplings accounted for the major oligomerization mechanism.

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.

Binding of green tea epigallocatechin gallate to the arginine kinase active site from the brown recluse spider (Loxosceles laeta): A potential synergist to chemical pesticides

Loxosceles spp. spiders can cause serious public health issues. Chemical control is commonly used, leading to health and environmental problems. Identifying molecular targets and using them with natural compounds can help develop safer and eco-friendlier biopesticides. We studied the kinetics and predicted structural characteristics of arginine kinase (EC 2.7.3.3) from Loxosceles laeta (LlAK), a key enzyme in the energy metabolism of these organisms. Additionally, we explored (-)-epigallocatechin gallate (EGCG), a green tea flavonoid, as a potential lead compound for the LlAK active site through fluorescence and in silico analysis, such as molecular docking and molecular dynamics (MD) simulation and MM/PBSA analyses. The results indicate that LlAK is a highly efficient enzyme (K m Arg 0.14 mM, K m ATP 0.98 mM, k cat 93 s-1, k cat/K m Arg 630 s-1 mM-1, k cat/K m ATP 94 s-1 mM-1), which correlates with its structure similarity to others AKs (such as Litopenaeus vannamei, Polybetes pythagoricus, and Rhipicephalus sanguineus) and might be related to its important function in the spider's energetic metabolism. Furthermore, the MD and MM/PBSA analysis suggests that EGCG interacted with LlAK, specifically at ATP/ADP binding site (RMSD <1 nm) and its interaction is energetically favored for its binding stability (-40 to -15 kcal/mol). Moreover, these results are supported by fluorescence quenching analysis (K d 58.3 μM and K a 1.71 × 104 M-1). In this context, LlAK is a promising target for the chemical control of L. laeta, and EGCG could be used in combination with conventional pesticides to manage the population of Loxosceles species in urban areas.

Natural product-based treatment potential for type 2 diabetes mellitus and cardiovascular disease

BACKGROUND

Type 2 diabetes (T2D) is a metabolic disease of impaired glucose utilization and a major cause of cardiovascular disease (CVD). The pathogenesis of both diseases shares common risk factors and mechanisms, and both are significant contributors to global morbidity and mortality. Supplements of natural products for T2D mellitus (T2DM) and CVD can be seen as a potential preventive and effective therapeutic strategy.

AIM

To critically evaluate the therapeutic potential of natural products in T2D and coronary artery disease (CAD).

METHODS

By using specific keywords, we strategically searched the PubMed database. Randomized controlled trials (RCTs) were searched as the primary focus that examined the effect of natural products on glycemic control, oxidative stress, and antioxidant levels. We focused on outcomes such as low blood glucose levels, adjustment on markers of oxidative stress and antioxidants. After screening full-length papers, we included 9 RCTs in our review that met our inclusion criteria.

RESULTS

In the literature search on the database, we found that various natural products like plant secondary metabolites play a diverse role in the management of CAD. American ginseng, sesame oil and cocoa flavanols proved effective in lowering blood glucose levels and controlling blood pressure, which are key factors in managing T2DM and CVD. In diabetic patients Melissa officinalis effectively reduce inflammation and shows diabetes prevention. Both fish oil and flaxseed oil reduced insulin levels and inflammatory markers, suggesting benefits for both conditions. The lipid profile and endothelial function were enhanced by Nigella sativa oil and Terminalia chebula, which is significant for the management of cardiovascular risk factors in T2DM. Additionally Bilberry extract also showed promise for improving glycemic control in patients with T2DM.

CONCLUSION

The high level of antioxidant, anti-inflammatory, and anti-angiogenic properties found in natural products makes them promising therapeutic options for the management of CAD, with the potential benefit of lowering the risk of CAD.

Natural Bioactive Compounds in the Management of Periodontal Diseases: A Comprehensive Review

Periodontal diseases, chronic inflammatory conditions affecting oral health, are primarily driven by microbial plaque biofilm and the body's inflammatory response, leading to tissue damage and potential tooth loss. These diseases have significant physical, psychological, social, and economic impacts, necessitating effective management strategies that include early diagnosis, comprehensive treatment, and innovative therapeutic approaches. Recent advancements in biomanufacturing have facilitated the development of natural bioactive compounds, such as polyphenols, terpenoids, alkaloids, saponins, and peptides, which exhibit antimicrobial, anti-inflammatory, and tissue regenerative properties. This review explores the biomanufacturing processes-microbial fermentation, plant cell cultures, and enzymatic synthesis-and their roles in producing these bioactive compounds for managing periodontal diseases. The integration of these natural compounds into periodontal therapy offers promising alternatives to traditional treatments, potentially overcoming issues like antibiotic resistance and the disruption of the natural microbiota, thereby improving patient outcomes.

Exploring Tau Fibril-Disaggregating and Antioxidating Molecules Binding to Membrane-Bound Amyloid Oligomers Using Machine Learning-Enhanced Docking and Molecular Dynamics

Intracellular tau fibrils are sources of neurotoxicity and oxidative stress in Alzheimer's. Current drug discovery efforts have focused on molecules with tau fibril disaggregation and antioxidation functions. However, recent studies suggest that membrane-bound tau-containing oligomers (mTCOs), smaller and less ordered than tau fibrils, are neurotoxic in the early stage of Alzheimer's. Whether tau fibril-targeting molecules are effective against mTCOs is unknown. The binding of epigallocatechin-3-gallate (EGCG), CNS-11, and BHT-CNS-11 to in silico mTCOs and experimental tau fibrils was investigated using machine learning-enhanced docking and molecular dynamics simulations. EGCG and CNS-11 have tau fibril disaggregation functions, while the proposed BHT-CNS-11 has potential tau fibril disaggregation and antioxidation functions like EGCG. Our results suggest that the three molecules studied may also bind to mTCOs. The predicted binding probability of EGCG to mTCOs increases with the protein aggregate size. In contrast, the predicted probability of CNS-11 and BHT-CNS-11 binding to the dimeric mTCOs is higher than binding to the tetrameric mTCOs for the homo tau but not for the hetero tau-amylin oligomers. Our results also support the idea that anionic lipids may promote the binding of molecules to mTCOs. We conclude that tau fibril-disaggregating and antioxidating molecules may bind to mTCOs, and that mTCOs may also be useful targets for Alzheimer's drug design.

EGCG Suppresses Adipogenesis and Promotes Browning of 3T3-L1 Cells by Inhibiting Notch1 Expression

BACKGROUND

With the changes in lifestyle and diet structure, the incidence of obesity has increased year by year, and obesity is one of the inducements of many chronic metabolic diseases. Epigallocatechin gallate (EGCG), which is the most abundant component of tea polyphenols, has been used for many years to improve obesity and its complications. Though it has been reported that EGCG can improve obesity through many molecular mechanisms, EGCG may have many mechanisms yet to be explored. In this study, we explored other possible mechanisms through molecular docking and in vitro experiments.

METHODS

AutoDock Vina was selected for conducting the molecular docking analysis to elucidate the interaction between EGCG and Notch1, while molecular dynamics simulations were employed to validate this interaction. Then, the new regulation mechanism of EGCG on obesity was verified with in vitro experiments, including a Western blot experiment, immunofluorescence experiment, oil red O staining, and other experiments in 3T3-L1 adipocytes.

RESULTS

The molecular docking results showed that EGCG could bind to Notch1 protein through hydrogen bonding. In vitro cell experiments demonstrated that EGCG can significantly reduce the sizes of lipid droplets of 3T3-L1 adipocytes and promote UCP-1 expression by inhibiting the expression of Notch1 in 3T3-L1 adipocytes, thus promoting mitochondrial biogenesis.

CONCLUSIONS

In this study, molecular docking and in vitro cell experiments were used to explore the possible mechanism of EGCG to improve obesity by inhibiting Notch1.

The effect of EGCG/tyrosol-loaded chitosan/lecithin nanoparticles on hyperglycemia and hepatic function in streptozotocin-induced diabetic mice

We aimed to study the potential of epigallocatechin-3-gallate/tyrosol-loaded chitosan/lecithin nanoparticles (EGCG/tyrosol-loaded C/L NPs) in streptozotocin-induced type 2 diabetes mellitus (T2DM) mice. The EGCG/tyrosol-loaded C/L NPs were created using the self-assembly method. Dynamic light scattering, Field Emission Scanning Electron Microscopy, and Fourier transform infrared spectroscopy were utilized to characterize the nanoparticle. Furthermore, in streptozotocin-induced T2DM mice, treatment with EGCG/tyrosol-loaded C/L NPs on fasting blood sugar levels, the expression of PCK1 and G6Pase, and IL-1β in the liver, liver glutathione content, nanoparticle toxicity on liver cells, and liver reactive oxygen species were measured. Our findings showed that EGCG/tyrosol-loaded C/L NPs had a uniform size distribution, and encapsulation efficiencies of 84 % and 89.1 % for tyrosol and EGCG, respectively. The nanoparticles inhibited PANC-1 cells without affecting normal HFF cells. Furthermore, EGCG/tyrosol-loaded C/L NP treatment reduced fasting blood sugar levels, elevated hepatic glutathione levels, enhanced liver cell viability, and decreased reactive oxygen species levels in diabetic mice. The expression of gluconeogenesis-related genes (PCK1 and G6 Pase) and the inflammatory gene IL-1β was downregulated by EGCG/tyrosol-loaded C/L NPs. In conclusion, the EGCG/tyrosol-loaded C/L NPs reduced hyperglycemia, oxidative stress, and inflammation in diabetic mice. These findings suggest that EGCG/tyrosol-loaded C/L NPs could be a promising therapeutic option for type 2 diabetes management.

EGCG Disrupts the LIN28B/Let-7 Interaction and Reduces Neuroblastoma Aggressiveness

Neuroblastoma (NB) is the most commonly diagnosed extracranial solid tumor in children, accounting for 15% of all childhood cancer deaths. Although the 5-year survival rate of patients with a high-risk disease has increased in recent decades, NB remains a challenge in pediatric oncology, and the identification of novel potential therapeutic targets and agents is an urgent clinical need. The RNA-binding protein LIN28B has been identified as an oncogene in NB and is associated with a poor prognosis. Given that LIN28B acts by negatively regulating the biogenesis of the tumor suppressor let-7 miRNAs, we reasoned that selective interference with the LIN28B/let-7 miRNA interaction would increase let-7 miRNA levels, ultimately leading to reduced NB aggressiveness. Here, we selected (-)-epigallocatechin 3-gallate (EGCG) out of 4959 molecules screened as the molecule with the best inhibitory activity on LIN28B/let-7 miRNA interaction and showed that treatment with PLC/PLGA-PEG nanoparticles containing EGCG (EGCG-NPs) led to an increase in mature let-7 miRNAs and a consequent inhibition of NB cell growth. In addition, EGCG-NP pretreatment reduced the tumorigenic potential of NB cells in vivo. These experiments suggest that the LIN28B/let-7 miRNA axis is a good therapeutic target in NB and that EGCG, which can interfere with this interaction, deserves further preclinical evaluation.

Epigallocatechin-3-Gallate attenuates lipopolysacharide-induced pneumonia via modification of inflammation, oxidative stress, apoptosis, and autophagy

BACKGROUND

Pneumonia, the acute inflammation of lung tissue, is multi-factorial in etiology. Hence, continuous studies are conducted to determine the mechanisms involved in the progression of the disease and subsequently suggest effective treatment. The present study attempted to evaluate the effects of Epigallocatechin-3-Gallate (EGCG), an herbal antioxidant, on inflammation, oxidative stress, apoptosis, and autophagy in a rat pneumonia model.

METHODS

Forty male Wistar rats, 5 months old and 250-290 g were divided into four groups including control, EGCG, experimental pneumonia (i/p LPS injection, 1 mg/kg), and experimental pneumonia treated with EGCG (i/p, 15 mg/kg, 1 h before and 3 h after LPS instillation). Total cell number in the bronchoalveolar lavage fluid, inflammation (TNF-a, Il-6, IL-1β, and NO), oxidative stress (Nrf2, HO-1, SOD, CAT, GSH, GPX, MDA, and TAC), apoptosis (BCL-2, BAX, CASP-3 and CASP-9), and autophagy (mTOR, LC3, BECN1) were evaluated.

RESULTS

The findings demonstrated that EGCG suppresses the LPS-induced activation of inflammatory pathways by a significant reduction of inflammatory markers (p-value < 0.001). In addition, the upregulation of BCL-2 and downregulation of BAX and caspases revealed that EGCG suppressed LPS-induced apoptosis. Furthermore, ECGC suppressed oxidative injury while promoting autophagy in rats with pneumonia (p-value < 0.05).

CONCLUSION

The current study revealed that EGCG could suppress inflammation, oxidative stress, apoptosis, and promote autophagy in experimental pneumonia models of rats suggesting promising therapeutical properties of this compound to be used in pneumonia management.

Epigallocatechin-3-gallate improves the quality of maternally aged oocytes

The decline in female fertility as age advances is intricately linked to the diminished developmental potential of oocytes. Despite this challenge, the strategies available to enhance the quality of aged oocytes remain limited. Epigallocatechin-3-gallate (EGCG), characterised by its anti-inflammatory, antioxidant and tissue protective properties, holds promise as a candidate for improving the quality of maternally aged oocytes. In this study, we explored the precise impact and underlying mechanisms of EGCG on aged oocytes. EGCG exhibited the capacity to enhance the quality of aged oocytes both in vitro and in vivo. Specifically, the application of EGCG in vitro resulted in noteworthy improvements, including an increased rate of first polar body extrusion, enhanced mitochondrial function, refined spindle morphology and a reduction in oxidative stress. These beneficial effects were further validated by the improved fertility observed among aged mice. In addition, our findings propose that EGCG might augment the expression of Arf6. This augmentation, in turn, contributes to the assembly of spindle-associated F-actin, which can contribute to mitigate the aneuploidy induced by the disruption of spindle F-actin within aged oocytes. This work thus contributes not only to understanding the role of EGCG in bolstering oocyte health, but also underscores its potential as a therapeutic intervention to address fertility challenges associated with advanced age.

Epigallocatechin-3-gallate protects sepsis-induced myocardial dysfunction by inhibiting the nuclear factor-κB signaling pathway

Sepsis-induced myocardial dysfunction (SIMD) has become one of the most lethal complications of sepsis, while the treatment was limited by a shortage of pertinent drugs. Epigallocatechin-3-gallate (EGCG) is the highest content of active substances in green tea, and its application in cardiovascular diseases has broad prospects. This study was conducted to test the hypothesis that EGCG was able to inhibit lipopolysaccharide (LPS) induced myocardial dysfunction and investigate the underlying molecular mechanisms. The cardiac systolic function was assessed by echocardiography. The cardiomyocyte apoptosis was determined by TUNEL staining. The expression of inflammatory factors and apoptosis-related protein, cardiac markers were examined by Western Blot and qRT-PCR. EGCG effectively improve LPS-induced cardiac function damage, enhance left ventricular systolic function, and restore myocardial cell vitality. It can effectively inhibit the upregulation of TLR4 expression induced by LPS and inhibit IκB α/NF- κB/p65 signaling pathway, thereby inhibiting cardiomyocyte apoptosis and improving myocarditis. In conclusion, EGCG protects against SIMD through anti-inflammatory and anti-apoptosis effects; it was mediated by the inhibition of the TLR4/NF-κB signal pathway. Our results demonstrated that EGCG might be a possible medicine for SIMD prevention and treatment.

Therapeutic potentialities of green tea (Camellia sinensis) in ischemic stroke: biochemical and molecular evidence

Ischemic stroke is a leading cause of disability and death in patients. Despite considerable recent advances in the treatment of ischemic stroke, only a limited number of effective neuroprotective agents are available for stroke. Green tea (Camellia sinensis) is a popular herbal plant, and numerous studies have indicated its health benefits for several diseases. Green tea is of interest due to its high content of catechin derivatives, including epicatechin, gallocatechin, epicatechin gallate, epigallocatechin, and epigallocatechin-3-gallate. This review tried to develop a feasible background for the potential effects of green tea and its bioactive derivatives concerning protection against ischemic stroke. Green tea's antioxidants, anti-inflammatory, anti-apoptotic, and neuroprotective effects are believed to be efficacious in stroke treatment. Evidence supports the idea that green tea can be used to assist in treating ischemic stroke.

EGCG, a Green Tea Compound, Increases NO Production and Has Antioxidant Action in a Static and Shear Stress In Vitro Model of Preeclampsia

Preeclampsia (PE) is a gestational hypertensive disease characterized by endothelial dysfunction. Epigallocatechin-3-gallate (EGCG), the main compound in green tea, is a promising therapeutic target for the disease. By activating eNOS, EGCG increased NO production and exerted an important antioxidant action, but its specific impact in the context of PE remains understudied. The aim of this study is to evaluate the effects of EGCG on endothelial function in static and shear stress in in vitro models of PE. Endothelial cells were incubated with healthy (HP) and preeclamptic (PE) pregnant women's plasma, and the latter group was treated with EGCG. Additionally, NOS (L-NAME) and PI3K protein (LY249002) inhibitors were also used. The levels of NO, ROS, and O2•- were evaluated, as well as the antioxidant potential. These investigations were also carried out in a shear stress model. We found that EGCG increases the NO levels, which were reduced in the PE group. This effect was attenuated with the use of L-NAME and LY249002. Furthermore, EGCG increased the antioxidant capacity of PE, but its action decreased with LY294002. In cells subjected to shear stress, EGCG increased nitrite levels in the PE group and maintained its action on the antioxidant capacity. This is the first study of the effects of EGCG in this experimental model, as well as the investigation of its effects along with shear stress. Our findings suggest that EGCG improves parameters of endothelial dysfunction in vitro, making it a promising target in the search for treatments for the disease.

Epigallocatechin-3-Gallate and Genistein for Decreasing Gut Dysbiosis, Inhibiting Inflammasomes, and Aiding Autophagy in Alzheimer's Disease

There are approximately 24 million cases of Alzheimer's disease (AD) worldwide, and the number of cases is expected to increase four-fold by 2050. AD is a neurodegenerative disease that leads to severe dementia in most patients. There are several neuropathological signs of AD, such as deposition of amyloid beta (Aβ) plaques, formation of neurofibrillary tangles (NFTs), neuronal loss, activation of inflammasomes, and declining autophagy. Several of these hallmarks are linked to the gut microbiome. The gastrointestinal (GI) tract contains microbial diversity, which is important in regulating several functions in the brain via the gut-brain axis (GBA). The disruption of the balance in the gut microbiota is known as gut dysbiosis. Recent studies strongly support that targeting gut dysbiosis with selective bioflavonoids is a highly plausible solution to attenuate activation of inflammasomes (contributing to neuroinflammation) and resume autophagy (a cellular mechanism for lysosomal degradation of the damaged components and recycling of building blocks) to stop AD pathogenesis. This review is focused on two bioflavonoids, specifically epigallocatechin-3-gallate (EGCG) and genistein (GS), as a possible new paradigm of treatment for maintaining healthy gut microbiota in AD due to their implications in modulating crucial AD signaling pathways. The combination of EGCG and GS has a higher potential than either agent alone to attenuate the signaling pathways implicated in AD pathogenesis. The effects of EGCG and GS on altering gut microbiota and GBA were also explored, along with conclusions from various delivery methods to increase the bioavailability of these bioflavonoids in the body.

Insight into the function of tetranectin in human diseases: A review and prospects for tetranectin-targeted disease treatment

Tetranectin (TN), a serum protein, is closely associated with different types of cancers. TN binds plasminogen and promotes the proteolytic activation of plasminogen into plasmin, which suggests that TN is involved in remodeling the extracellular matrix and cancer tissues during cancer development. TN is also associated with other diseases, such as developmental disorders, cardiovascular diseases, neurological diseases, inflammation, and diabetes. Although the functional mechanism of TN in diseases is not fully elucidated, TN binds different proteins, such as structural protein, a growth factor, and a transcription regulator. Moreover, TN changes and regulates protein functions, indicating that TN-binding proteins mediate the association between TN and diseases. This review summarizes the current knowledge of TN-associated diseases and TN functions with TN-binding proteins in different diseases. In addition, potential TN-targeted disease treatment by inhibiting the interaction between TN and its binding proteins is discussed.

Monocyte (THP-1) Response to Silver Nanoparticles Synthesized with Rumex hymenosepalus Root Extract

The study, synthesis, and application of nanomaterials in medicine have grown exponentially in recent years. An example of this is the understanding of how nanomaterials activate or regulate the immune system, particularly macrophages. In this work, nanoparticles were synthesized using Rumex hymenosepalus as a reducing agent (AgRhNPs). According to thermogravimetric analysis, the metal content of nanoparticles is 55.5% by weight. The size of the particles ranges from 5-26 nm, with an average of 11 nm, and they possess an fcc crystalline structure. The presence of extract molecules on the nanomaterial was confirmed by UV-Vis and FTIR. It was found by UPLC-qTOF that the most abundant compounds in Rh extract are flavonols, flavones, isoflavones, chalcones, and anthocyanidins. The viability and apoptosis of the THP-1 cell line were evaluated for AgRhNPs, commercial nanoparticles (AgCNPs), and Rh extract. The results indicate a minimal cytotoxic and apoptotic effect at a concentration of 12.5 μg/mL for both nanoparticles and 25 μg/mL for Rh extract. The interaction of the THP-1 cell line and treatments was used to evaluate the polarization of monocyte subsets in conjunction with an evaluation of CCR2, Tie-2, and Arg-1 expression. The AgRhNPs nanoparticles and Rh extract neither exhibited cytotoxicity in the THP-1 monocyte cell line. Additionally, the treatments mentioned above exhibited anti-inflammatory effects by maintaining the classical monocyte phenotype CD14++CD16, reducing pro-inflammatory interleukin IL-6 production, and increasing IL-4 production.

Metabolome analysis to investigate the effect of heavy metal exposure and chemoprevention agents on toxic injury caused by a multi-heavy metal mixture in rats

Heavy metal pollution is a significant threat to both the environment and living organisms. This is especially vital considering the persistent and cumulative nature of heavy metal exposure, which can lead to severe and chronic health consequences for individuals. Therefore, implementing effective treatments is critical to addressing the serious public health issues posed by heavy metal pollution. In this study, nontargeted metabolomics was carried out to investigate the metabolic changes associated with long-term low-dose intake of mixed heavy metal pollutants (MHMPs) in liver, kidney, and plasma samples of Sprague-Dawley (SD) rats with and without treatment to reveal the underlying toxic effects of MHMPs and the effects of chemoprevention agents, including epigallocatechin-3-gallate (EGCG), trisodium citrate dihydrate (TCD), and glutathione (GSH). In the liver, kidney, and plasma, we observed a total of 21, 69, and 16 metabolites, respectively, exhibiting significant differences (P < 0.05, fold change >1.2 or <0.83, and VIP ≥ 1) between the control group and the mixture group. The findings demonstrated that exposure to MHMPs leads to the dysregulation of numerous metabolic pathways, with a particular emphasis on purine metabolism and aminoacyl-tRNA biosynthesis with upregulated renal purine metabolites and downregulated hepatic purine metabolites as well as renal aminoacyl-tRNA biosynthesis-related metabolites. However, the application of chemical protectants was shown to partially restore the metabolic alterations induced by MHMPs, particularly purine metabolism-related metabolites, including hepatic adenine and renal adenine, guanine, guanosine, adenosine monophosphate (AMP), and hypoxanthine. In addition, liver adenosine, kidney inosine and L-phenylalanine were considered the main regulated sites based on their significant correlations with multiple heavy metals. Our study provides crucial insights into the toxicological mechanisms of heavy metal pollution and has the potential to guide the development of effective preventive strategies.

Natural Polyphenols in Cancer Management: Promising Role, Mechanisms, and Chemistry

BACKGROUND

Although cancers emerge rapidly and cancer cells divide aggressively, which affects our vital organ systems. Recently, cancer treatments are targeted immune systems mediating intrinsic cellular mechanisms. Natural efficacious polyphenols have been exhibited to help prevent most cancers and reverse the progression of cancers.

METHODS

Many resources have been used to know the promising role of polyphenols in preventing and treating cancers. The electronic databases include Science Direct, Google, Google Scholar, PubMed, and Scopus. The search was limited to the English language only.

RESULTS

Polyphenols have been reported as anti-metastatic agents that explore the promising role of these compounds in cancer prevention. Such agents act through many signaling pathways, including PI3K/Akt and TNF-induced signaling pathways. The chemical modifications of polyphenols and the structure-activity relationships (SARs) between polyphenols and anticancer activities have also been discussed.

CONCLUSION

Many research papers were reported to explain the anti-cancer potential of Polyphenols, The SARs between polyphenols and anti-cancer activities, which correlate structures of polyphenols with significant chemotherapeutic action. The mechanism of anti-cancer potential is to be added for searching for new anti-cancer natural products.

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.

Phytochemicals: Targeting autophagy to treat psoriasis

BACKGROUND

Psoriasis is an immune-mediated chronic inflammatory skin disease characterized by well-defined erythema and white scales, which affects approximately 2% of the worldwide population and causes long-term distress to patients. Therefore, development of safe and effective therapeutic drugs is imminent. Autophagy, an evolutionarily conserved catabolic process, degrades intracellular constituents to maintain cellular energy homeostasis. Numerous studies have revealed that autophagy is closely related to immune function, such as removal of intracellular bacteria, inflammatory cytokine secretion, antigen presentation, and lymphocyte development. Phytochemicals derived from natural plants are often used to treat psoriasis due to their unique therapeutic properties and favorable safety. So far, a mass of phytochemicals have been proven to be able to activate autophagy and thus alleviate psoriasis. This review aimed to provide directions for finding phytochemicals that target autophagy to treat psoriasis.

METHODS

The relevant literatures were collected from classical TCM books and a variety of databases (PubMed, Google Scholar, ScienceDirect, Springer Link, Web of Science and China National Knowledge Infrastructure) till December 2022. Search terms were "Phytochemical", "Psoriasis" and "Autophagy". The retrieved data followed PRISMA criteria (preferred reporting items for systematic review).

RESULTS

Phytochemicals treat psoriasis mainly through regulating immune cell function, inhibiting excessive inflammatory response, and reducing oxidative stress. While the role and mechanism of autophagy in the pathogenesis of psoriasis have been confirmed in human trials, most of the evidence for phytochemicals that target autophagy to treat psoriasis comes from animal studies. The research focusing on the role of phytochemical-mediated autophagy in the prevention and treatment of psoriasis is limited, and the definite relationship between phytochemical-regulated autophagy and treatment of psoriasis still deserves further experimental confirmation.

CONCLUSIONS

Phytochemicals with autophagic activities will provide new insights into the therapeutic intervention for psoriasis.

Caenorhabditis elegans as an in vivo model for the identification of natural antioxidants with anti-aging actions

Natural antioxidants have recently emerged as a highly exciting and significant topic in anti-aging research. Diverse organism models present a viable protocol for future research. Notably, many breakthroughs on natural antioxidants have been achieved in the nematode Caenorhabditis elegans, an animal model frequently utilized for the study of aging research and anti-aging drugs in vivo. Due to the conservation of signaling pathways on oxidative stress resistance, lifespan regulation, and aging disease between C. elegans and multiple high-level organisms (humans), as well as the low and controllable cost of time and labor, it gradually develops into a trustworthy in vivo model for high-throughput screening and validation of natural antioxidants with anti-aging actions. First, information and models on free radicals and aging are presented in this review. We also describe indexes, detection methods, and molecular mechanisms for studying the in vivo antioxidant and anti-aging effects of natural antioxidants using C. elegans. It includes lifespan, physiological aging processes, oxidative stress levels, antioxidant enzyme activation, and anti-aging pathways. Furthermore, oxidative stress and healthspan improvement induced by natural antioxidants in humans and C. elegans are compared, to understand the potential and limitations of the screening model in preclinical studies. Finally, we emphasize that C. elegans is a useful model for exploring more natural antioxidant resources and uncovering the mechanisms underlying aging-related risk factors and diseases.

The Green Tea Polyphenol Epigallocatechin-Gallate (EGCG) Interferes with Microcin E492 Amyloid Formation

Microcin E492 (MccE492) is an antimicrobial peptide and proposed virulence factor produced by some Klebsiella pneumoniae strains, which, under certain conditions, form amyloid fibers, leading to the loss of its antibacterial activity. Although this protein has been characterized as a model functional amyloid, the secondary structure transitions behind its formation, and the possible effect of molecules that inhibit this process, have not been investigated. In this study, we examined the ability of the green tea flavonoid epigallocatechin gallate (EGCG) to interfere with MccE492 amyloid formation. Aggregation kinetics followed by thioflavin T binding were used to monitor amyloid formation in the presence or absence of EGCG. Additionally, synchrotron radiation circular dichroism (SRCD) and transmission electron microscopy (TEM) were used to study the secondary structure, thermal stability, and morphology of microcin E492 fibers. Our results showed that EGCG significantly inhibited the formation of the MccE492 amyloid, resulting in mainly amorphous aggregates and small oligomers. However, these aggregates retained part of the β-sheet SRCD signal and a high resistance to heat denaturation, suggesting that the aggregation process is sequestered or deviated at some stage but not completely prevented. Thus, EGCG is an interesting inhibitor of the amyloid formation of MccE492 and other bacterial amyloids.

The synergistic effects of polyphenols and intestinal microbiota on osteoporosis

Osteoporosis is a common metabolic disease in middle-aged and elderly people. It is characterized by a reduction in bone mass, compromised bone microstructure, heightened bone fragility, and an increased susceptibility to fractures. The dynamic imbalance between osteoblast and osteoclast populations is a decisive factor in the occurrence of osteoporosis. With the increase in the elderly population in society, the incidence of osteoporosis, disability, and mortality have gradually increased. Polyphenols are a fascinating class of compounds that are found in both food and medicine and exhibit a variety of biological activities with significant health benefits. As a component of food, polyphenols not only provide color, flavor, and aroma but also act as potent antioxidants, protecting our cells from oxidative stress and reducing the risk of chronic disease. Moreover, these natural compounds exhibit anti-inflammatory properties, which aid in immune response regulation and potentially alleviate symptoms of diverse ailments. The gut microbiota can degrade polyphenols into more absorbable metabolites, thereby increasing their bioavailability. Polyphenols can also shape the gut microbiota and increase its abundance. Therefore, studying the synergistic effect between gut microbiota and polyphenols may help in the treatment and prevention of osteoporosis. By delving into how gut microbiota can enhance the bioavailability of polyphenols and how polyphenols can shape the gut microbiota and increase its abundance, this review offers valuable information and references for the treatment and prevention of osteoporosis.

An Update on Impacts of Epigallocatechin Gallate Co-administration in Modulating Pharmacokinetics of Statins, Calcium Channel Blockers, and Beta-blockers

Brewed green tea, green tea extract, and its primary active compound, epigallocatechin gallate, may interact with drugs and alter the drug's therapeutic effectiveness, ultimately leading to therapeutic failure or drug overdose. Several isolated reports have claimed that epigallocatechin gallate is the main active ingredient that causes these effects. While a few studies aimed to uncover evidence of epigallocatechin gallate-drug interactions, no study has thoroughly and collectively reviewed them. Epigallocatechin gallate is a potential cardioprotective agent used by many patients with cardiovascular diseases as a complementary medicine alongside conventional modern medications, either with or without the knowledge of their physicians. Therefore, this review focuses on the impact of concurrent epigallocatechin gallate supplementation on pharmacokinetics and pharmacodynamics of several commonly used cardiovascular drugs (statins, beta-blockers, and calcium channel blockers). The PubMed index was searched for key words related to this review, without year limit, and the results were analyzed for interactions of cardiovascular drugs with epigallocatechin gallate. This review concludes that epigallocatechin gallate increases systemic circulation of several statins (simvastatin, fluvastatin, rosuvastatin) and calcium channel blockers (verapamil), but decreases the bioavailability of beta-blockers (nadolol, atenolol, bisoprolol). Further studies on its clinical significance in affecting drug efficacy are required.

Phytochemicals for the prevention and treatment of pancreatic cancer: Current progress and future prospects

Pancreatic cancer is the third leading cause of cancer-related deaths in the United States, owing to its aggressive nature and suboptimal treatment options, emphasizing the need for novel therapeutic approaches. Emerging studies have exhibited promising results regarding the therapeutic utility of plant-derived compounds (phytochemicals) in pancreatic cancer. The purpose of this review is to evaluate the potential of phytochemicals in the treatment and prevention of pancreatic cancer. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses was applied to collect articles for this review. Scholarly databases, including PubMed, Scopus and ScienceDirect, were queried for relevant studies using the following keywords: phytochemicals, phenolics, terpenoids, alkaloids, sulfur-containing compounds, in vitro, in vivo, clinical studies, pancreatic cancer, tumour, treatment and prevention. Aggregate results pooled from qualified studies indicate phytochemicals can inhibit pancreatic cancer cell growth or decrease tumour size and volume in animal models. These effects have been attributed to various mechanisms, such as increasing proapoptotic factors, decreasing antiapoptotic factors, or inducing cell death and cell cycle arrest. Notable signalling pathways modulated by phytochemicals include the rat sarcoma/mitogen activated protein kinase, wingless-related integration site/β-catenin and phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signal transduction pathways. Clinically, phytochemicals have been found to increase survival while being well-tolerated and safe, though research is scarce. While these promising results have produced great interest in this field, further in-depth studies are required to characterize the anticancer activities of phytochemicals before they can be utilized to prevent or treat pancreatic cancer in clinical practice.

Epigallocatechin-3-Gallate Therapeutic Potential in Cancer: Mechanism of Action and Clinical Implications

Cellular signaling pathways involved in the maintenance of the equilibrium between cell proliferation and apoptosis have emerged as rational targets that can be exploited in the prevention and treatment of cancer. Epigallocatechin-3-gallate (EGCG) is the most abundant phenolic compound found in green tea. It has been shown to regulate multiple crucial cellular signaling pathways, including those mediated by EGFR, JAK-STAT, MAPKs, NF-κB, PI3K-AKT-mTOR, and others. Deregulation of the abovementioned pathways is involved in the pathophysiology of cancer. It has been demonstrated that EGCG may exert anti-proliferative, anti-inflammatory, and apoptosis-inducing effects or induce epigenetic changes. Furthermore, preclinical and clinical studies suggest that EGCG may be used in the treatment of numerous disorders, including cancer. This review aims to summarize the existing knowledge regarding the biological properties of EGCG, especially in the context of cancer treatment and prophylaxis.

Nanotechnology-Based Topical Delivery of Natural Products for the Management of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic eczematous inflammatory disease that may arise from environmental, genetic, and immunological factors. Despite the efficacy of current treatment options such as corticosteroids, such approaches are mainly focused on symptom relief and may present certain undesirable side effects. In recent years, isolated natural compounds, oils, mixtures, and/or extracts have gained scientific attention because of their high efficiency and moderate to low toxicity. Despite their promising therapeutic effects, the applicability of such natural healthcare solutions is somewhat limited by their instability, poor solubility, and low bioavailability. Therefore, novel nanoformulation-based systems have been designed to overcome these limitations, thus enhancing the therapeutic potential, by promoting the capacity of these natural drugs to properly exert their action in AD-like skin lesions. To the best of our knowledge, this is the first literature review that has focused on summarizing recent nanoformulation-based solutions loaded with natural ingredients, specifically for the management of AD. We suggest that future studies should focus on robust clinical trials that may confirm the safety and effectiveness of such natural-based nanosystems, thus paving the way for more reliable AD treatments.

Therapeutic Potential of Polyphenols and Other Micronutrients of Marine Origin

Polyphenols are compounds found in various plants and foods, known for their antioxidant and anti-inflammatory properties. Recently, researchers have been exploring the therapeutic potential of marine polyphenols and other minor nutrients that are found in algae, fish and crustaceans. These compounds have unique chemical structures and exhibit diverse biological properties, including anti-inflammatory, antioxidant, antimicrobial and antitumor action. Due to these properties, marine polyphenols are being investigated as possible therapeutic agents for the treatment of a wide variety of conditions, such as cardiovascular disease, diabetes, neurodegenerative diseases and cancer. This review focuses on the therapeutic potential of marine polyphenols and their applications in human health, and also, in marine phenolic classes, the extraction methods, purification techniques and future applications of marine phenolic compounds.

Supplementation with a New Standardized Extract of Green and Black Tea Exerts Antiadipogenic Effects and Prevents Insulin Resistance in Mice with Metabolic Syndrome

Insulin resistance is one of the main characteristics of metabolic syndrome (MetS) and the main cause of the development of type II diabetes. The high prevalence of this syndrome in recent decades has made it necessary to search for preventive and therapeutic agents, ideally of natural origin, with fewer side effects than conventional pharmacological treatments. Tea is widely known for its medicinal properties, including beneficial effects on weight management and insulin resistance. The aim of this study was to analyze whether a standardized extract of green and black tea (ADM^® Complex Tea Extract (CTE)) prevents the development of insulin resistance in mice with MetS. For this purpose, C57BL6/J mice were fed for 20 weeks with a standard diet (Chow), a diet with 56% kcal from fat and sugar (HFHS) or an HFHS diet supplemented with 1.6% CTE. CTE supplementation reduced body weight gain, adiposity and circulating leptin levels. Likewise, CTE also exerted lipolytic and antiadipogenic effects in 3T3-L1 adipocyte cultures and in the C. elegans model. Regarding insulin resistance, CTE supplementation significantly increased plasma adiponectin concentrations and reduced the circulating levels of insulin and the HOMA-IR. Incubation of liver, gastrocnemius muscle and retroperitoneal adipose tissue explants with insulin increased the pAkt/Akt ratio in mice fed with Chow and HFHS + CTE but not in those fed only with HFHS. The greater activation of the PI3K/Akt pathway in response to insulin in mice supplemented with CTE was associated with a decrease in the expression of the proinflammatory markers Mcp-1, IL-6, IL-1β or Tnf-α and with an overexpression of the antioxidant enzymes Sod-1, Gpx-3, Ho-1 and Gsr in these tissues. Moreover, in skeletal muscle, mice treated with CTE showed increased mRNA levels of the aryl hydrocarbon receptor (Ahr), Arnt and Nrf2, suggesting that the CTE's insulin-sensitizing effects could be the result of the activation of this pathway. In conclusion, supplementation with the standardized extract of green and black tea CTE reduces body weight gain, exerts lipolytic and antiadipogenic effects and reduces insulin resistance in mice with MetS through its anti-inflammatory and antioxidant effects.

Epigallocatechin-3-Gallate Attenuates Myocardial Dysfunction via Inhibition of Endothelial-to-Mesenchymal Transition

Cardiac tissue damage following ischemia leads to cardiomyocyte apoptosis and myocardial fibrosis. Epigallocatechin-3-gallate (EGCG), an active polyphenol flavonoid or catechin, exerts bioactivity in tissues with various diseases and protects ischemic myocardium; however, its association with the endothelial-to-mesenchymal transition (EndMT) is unknown. Human umbilical vein endothelial cells (HUVECs) pretreated with transforming growth factor β2 (TGF-β2) and interleukin 1β (IL-1β) were treated with EGCG to verify cellular function. In addition, EGCG is involved in RhoA GTPase transmission, resulting in reduced cell mobility, oxidative stress, and inflammation-related factors. A mouse myocardial infarction (MI) model was used to confirm the association between EGCG and EndMT in vivo. In the EGCG-treated group, ischemic tissue was regenerated by regulating proteins involved in the EndMT process, and cardioprotection was induced by positively regulating apoptosis and fibrosis of cardiomyocytes. Furthermore, EGCG can reactivate myocardial function due to EndMT inhibition. In summary, our findings confirm that EGCG is an impact activator controlling the cardiac EndMT process derived from ischemic conditions and suggest that supplementation with EGCG may be beneficial in the prevention of cardiovascular disease.

Anti-Allergic Effect of Dietary Polyphenols Curcumin and Epigallocatechin Gallate via Anti-Degranulation in IgE/Antigen-Stimulated Mast Cell Model: A Lipidomics Perspective

Polyphenol-rich foods exhibit anti-allergic/-inflammatory properties. As major effector cells of allergies, mast cells undergo degranulation after activation and then initiate inflammatory responses. Key immune phenomena could be regulated by the production and metabolism of lipid mediators by mast cells. Here, we analyzed the antiallergic activities of two representative dietary polyphenols, curcumin and epigallocatechin gallate (EGCG), and traced their effects on cellular lipidome rewiring in the progression of degranulation. Both curcumin and EGCG significantly inhibited degranulation as they suppressed the release of β-hexosaminidase, interleukin-4, and tumor necrosis factor-α from the IgE/antigen-stimulated mast cell model. A comprehensive lipidomics study involving 957 identified lipid species revealed that although the lipidome remodeling patterns (lipid response and composition) of curcumin intervention were considerably similar to those of EGCG, lipid metabolism was more potently disturbed by curcumin. Seventy-eight percent of significant differential lipids upon IgE/antigen stimulation could be regulated by curcumin/EGCG. LPC-O 22:0 was defined as a potential biomarker for its sensitivity to IgE/antigen stimulation and curcumin/EGCG intervention. The key changes in diacylglycerols, fatty acids, and bismonoacylglycerophosphates provided clues that cell signaling disturbances could be associated with curcumin/EGCG intervention. Our work supplies a novel perspective for understanding curcumin/EGCG involvement in antianaphylaxis and helps guide future attempts to use dietary polyphenols.

Advances in autophagy modulation of natural products in cervical cancer

ETHNOPHARMACOLOGICAL RELEVANCE

Natural products play a critical role in drug development and is emerging as a potential source of biologically active metabolites for therapeutic intervention, especially in cancer therapy. In recent years, there is increasing evidence that many natural products may modulate autophagy through various signaling pathways in cervical cancer. Understanding the mechanisms of these natural products helps to develop medications for cervical cancer treatments.

AIM OF THE STUDY

In recent years, there is increasing evidence that many natural products may modulate autophagy through various signaling pathways in cervical cancer. In this review, we briefly introduce autophagy and systematically describe several classes of natural products implicated in autophagy modulation in cervical cancer, hoping to provide valuable information for the development of cervical cancer treatments based on autophagy.

MATERIALS AND METHODS

We searched for studies on natural products and autophagy in cervical cancer on the online database and summarized the relationship between natural products and autophagy modulation in cervical cancer.

RESULTS

Autophagy is a lysosome-mediated catabolic process in eukaryotic cells that plays an important role in a variety of physiological and pathological processes, including cervical cancer. Abnormal expression of cellular autophagy and autophagy-related proteins has been implicated in cervical carcinogenesis, and human papillomavirus infection can affect autophagic activity. Flavonoids, alkaloids, polyphenols, terpenoids, quinones, and other compounds are important sources of natural products that act as anticancer agents. In cervical cancer, natural products exert the anticancer function mainly through the induction of protective autophagy.

CONCLUSIONS

The regulation of cervical cancer autophagy by natural products has significant advantages in inducing apoptosis, inhibiting proliferation, and reducing drug resistance in cervical cancer.

Effect of Different Extraction Methods on Anthocyanin Content in Hibiscus sabdariffa L. and their Antiplatelet and Vasorelaxant Properties

Hibiscus sabdariffa L. is a worldwide component for tea and beverages, being a natural source of anthocyanins, which are associated with cardiovascular activities. To investigate this relationship, we explored different methods of aqueous extraction on the anthocyanin content and antioxidant activity of H. sabdariffa L. calyx extract (HSCE). Pharmacological effects via platelet aggregation, calcium mobilization, cyclic nucleotide levels, vasodilator-stimulated phosphoprotein Ser157 and Ser239, and on the vasomotor response of aortic rings isolated from mice are studied herewith. We found that the application of ultrasonic turbolization, 20 min, combined with acidified water was significantly more effective in the extraction process, providing extracts with the highest levels of anthocyanins (8.73 and 9.63 mg/100 g) and higher antioxidant activity (6.66 and 6.78 μM trolox/g of sample). HSCE significantly inhibited (100-1000 μg/mL) arachidonic acid-induced platelet aggregation, reduced calcium mobilization, and increased cAMP and cGMP levels with VASPSer157 and VASPSer239 phosphorylation. Vasorelaxation reduction was confirmed by the aortic rings and endothelium assays treated with nitric oxide synthase inhibitors, soluble guanylyl cyclase (sGC) oxidizing agent, or Ca²⁺-activated K⁺ channel inhibitor. The increasing of cGMP levels could be understood considering the sGC stimulation by HSCE compounds in the specific stimulus domain, which allows an understanding of the observed antiplatelet and vasorelaxant properties of H. sabdariffa L. calyx extract.

Combination Chemotherapy with Selected Polyphenols in Preclinical and Clinical Studies-An Update Overview

This review article describes studies published over the past five years on the combination of polyphenols, which are the most studied in the field of anticancer effects (curcumin, quercetin, resveratrol, epigallocatechin gallate, and apigenin) and chemotherapeutics such as cisplatin, 5-fluorouracil, oxaliplatin, paclitaxel, etc. According to WHO data, research has been limited to five cancers with the highest morbidity rate (lung, colorectal, liver, gastric, and breast cancer). A systematic review of articles published in the past five years (from January 2018 to January 2023) was carried out with the help of all Web of Science databases and the available base of clinical studies. Based on the preclinical studies presented in this review, polyphenols can enhance drug efficacy and reduce chemoresistance through different molecular mechanisms. Considering the large number of studies, curcumin could be a molecule in future chemotherapy cocktails. One of the main problems in clinical research is related to the limited bioavailability of most polyphenols. The design of a new co-delivery system for drugs and polyphenols is essential for future clinical research. Some polyphenols work in synergy with chemotherapeutic drugs, but some polyphenols can act antagonistically, so caution is always required.

Nature's Toolbox Against Tau Aggregation: An Updated Review of Current Research

Tau aggregation is a hallmark of several neurodegenerative disorders, such as Alzheimer's disease (AD), frontotemporal dementia, and progressive supranuclear palsy. Hyperphosphorylated tau is believed to contribute to the degeneration of neurons and the development of these complex diseases. Therefore, one potential treatment for these illnesses is to prevent or counteract tau aggregation. In recent years, interest has been increasing in developing nature-derived tau aggregation inhibitors as a potential treatment for neurodegenerative disorders. Researchers have become increasingly interested in natural compounds with multifunctional features, such as flavonoids, alkaloids, resveratrol, and curcumin, since these molecules can interact simultaneously with the various targets of AD. Recent studies have demonstrated that several natural compounds can inhibit tau aggregation and promote the disassembly of pre-formed tau aggregates. Nature-derived tau aggregation inhibitors hold promise as a potential treatment for neurodegenerative disorders. However, it is important to note that more research is needed to fully understand the mechanisms by which these compounds exert their effects and their safety and efficacy in preclinical and clinical studies. Nature-derived inhibitors of tau aggregation are a promising new direction in the research of neurodegenerative complexities. This review focuses on the natural products that have proven to be a rich supply for inhibitors in tau aggregation and their uses in neurodegenerative complexities, including AD.

Natural products can modulate inflammation in intervertebral disc degeneration

Intervertebral discs (IVDs) play a crucial role in maintaining normal vertebral anatomy as well as mobile function. Intervertebral disc degeneration (IDD) is a common clinical symptom and is an important cause of low back pain (LBP). IDD is initially considered to be associated with aging and abnormal mechanical loads. However, over recent years, researchers have discovered that IDD is caused by a variety of mechanisms, including persistent inflammation, functional cell loss, accelerated extracellular matrix decomposition, the imbalance of functional components, and genetic metabolic disorders. Of these, inflammation is thought to interact with other mechanisms and is closely associated with the production of pain. Considering the key role of inflammation in IDD, the modulation of inflammation provides us with new options for mitigating the progression of degeneration and may even cause reversal. Many natural substances possess anti-inflammatory functions. Due to the wide availability of such substances, it is important that we screen and identify natural agents that are capable of regulating IVD inflammation. In fact, many studies have demonstrated the potential clinical application of natural substances for the regulation of inflammation in IDD; some of these have been proven to have excellent biosafety. In this review, we summarize the mechanisms and interactions that are responsible for inflammation in IDD and review the application of natural products for the modulation of degenerative disc inflammation.