Antioxidative effect of polyphenol extract prepared from various Chinese teas

Exploring the mechanism of Huanglian ointment in alleviating wound healing after anal fistula surgery through metabolomics and proteomics

Anal fistula is a common anal and intestinal disease. The wound of anal fistula surgery is open and polluting, which is the most difficult to heal among all surgical incisions. To investigate the mechanism of Huanglian ointment (HLO) on wound healing after anal fistula incision. The S. aureus infected wound in SD rats were used to imitate poor healing wound after anal fistula surgery. SD rats with wound sites (n = 24) were randomly divided into four groups (Control group, Model group, Potassium permanganate (PP) treatment group, and HLO treatment group). The wound healing rate was evaluated, HE staining was used to evaluate the pathological changes of each group, ELISA was used to detect the secretion of inflammatory factors in each group, and the mechanism was explored through metabolomics and proteomics in plasma rat. Compared to other groups, the rate of wound healing in the HLO group was higher on days 7 and 14. Histological analysis showed that collagen and fibroblast in HLO rats were significantly increased, inflammatory cells were reduced, and vascular endothelial permeability was increased. ELISA results showed that the secretion of inflammatory factors in HLO rats was significantly lower. Significant proteins and metabolites were identified in the wound tissues of the infected rats and HLO-treated rats, which were mainly attributed to Cdc42, Ctnnb1, Actr2, Actr3, Arpc1b, Itgam, Itgb2, Cttn, Linoleic acid metabolism, d-Glutamine and d-glutamate metabolism, Phenylalanine, tyrosine and tryptophan biosynthesis, Phenylalanine metabolism, alpha-Linolenic acid metabolism, and Ascorbate and aldarate metabolism. In conclusion, this study showed that HLO can promote S. aureus infected wound healing, and the data provide a theoretical basis for the treatment of wounds after anal fistula surgery with HLO.

Evaluation of the toxicity of Caralluma europaea (C.E) extracts and their effects on apoptosis and chemoresistance in pancreatic cancer cells

Pancreatic adenocarcinoma is a disease with no effective treatment. Chemo-resistance contributes to the dismal prognosis for patients diagnosed with the disease. This study aims to evaluate the toxicity and the effect of Caralluma europaea (C.E) extracts on cancer cell survival, apoptosis, chemo-resistance, and pro-cancer pathways, in pancreatic cancer. The acute and subacute toxicities of C.E extracts were evaluated. The cytotoxic effect on pancreatic cancer cell survival and apoptosis was determined by MTT assay and DNA fragmentation. The expression of cancer stemness markers was measured using Western blot. A molecular docking was used to test the possible effects of C.E compounds in inhibiting the Hedgehog and activating caspase-3. The hydroethanolic extract's DL50 was over 5000 mg/kg. During the subacute toxicity, only saponins extract showed some hepatic toxicity signs. Cells treated with C.E extracts combined with gemcitabine revealed an additive anti-survival activity. C.E extracts sensitized resistant MIA-PaCa-2 to gemcitabine treatment. Most of the C.E extracts downregulated the expression of cancer stemness-associated genes. Luteolin-7-O-glucoside presented the highest docking Gscore on human Smoothened. Isorhamnetin-3-O-rutinoside induced apoptosis via activation of caspase-3. C.E extracts can be considered safe in inhibiting pancreatic cancer cell survival, inducing apoptosis, and sensitizing cells to chemotherapy via Hedgehog inhibition and caspase-3 activation.Communicated by Ramaswamy H. Sarma.

The Effects of Green Tea Catechins in Hematological Malignancies

Green tea catechins are bioactive polyphenol compounds which have attracted significant attention for their diverse biological activities and potential health benefits. Notably, epigallocatechin-3-gallate (EGCG) has emerged as a potent apoptosis inducer through mechanisms involving caspase activation, modulation of Bcl-2 family proteins, disruption of survival signaling pathways and by regulating the redox balance, inducing oxidative stress. Furthermore, emerging evidence suggests that green tea catechins can modulate epigenetic alterations, including DNA methylation and histone modifications. In addition to their apoptotic actions, ROS signaling effects and reversal of epigenetic alterations, green tea catechins have shown promising results in promoting the differentiation of leukemia cells. This review highlights the comprehensive actions of green tea catechins and provides valuable insights from clinical trials investigating the therapeutic potential of green tea catechins in leukemia treatment. Understanding these multifaceted mechanisms and the outcomes of clinical trials may pave the way for the development of innovative strategies and the integration of green tea catechins into clinical practice for improving leukemia patient outcomes.

Effects of green tea extract treatment on erythropoiesis and iron parameters in iron-overloaded β-thalassemic mice

β-Thalassemia is characterized by ineffective erythropoiesis leading to chronic anemia. Thus, increased iron absorption from the duodenum and via blood transfusions is required to maintain normal blood hemoglobin (Hb) levels and iron chelators in the removal of excessive iron. Certain agents are also needed for the improvement of stress erythropoiesis and iron dysregulation. Green tea extract (GTE), which is rich in epigallocatechin-3-gallate (EGCG), is known to possess radical scavenging and iron-chelating activities. We aimed to assess the effects of green tea extract on erythroid regulators, iron mobilization and anti-lipid peroxidation in the liver, spleen, and kidneys of iron-loaded β-globin gene knockout thalassemic (BKO) mice. Our results indicate that treatments of green tea extract and/or deferiprone (DFP) diminished levels of plasma erythropoietin (EPO) and erythroferrone (ERFE), and consistently suppressed kidney Epo and spleen Erfe mRNA expressions (p < .05) in iron- loaded BKO mice when compared with untreated mice. Coincidently, the treatments decreased plasma ferritin (Ft) levels, iron content levels in the liver (p < .05), spleen (p < .05), and kidney tissues of iron-loaded BKO mice. Furthermore, lipid-peroxidation products in the tissues and plasma were also decreased when compared with untreated mice. This is the first evidence of the orchestral role of green tea extract abundant with epigallocatechin-3-gallate in improving ineffective erythropoiesis, iron dysregulation and oxidative stress in iron-overloaded β-thalassemic mice.

The LC-MS/MS Identification and Analgesic and Wound Healing Activities of Lavandula officinalis Chaix: In Vivo and In Silico Approaches

We earlier emphasized in vivo the lavender plant's (Lavandula officinalis Chaix.) anti-inflammatory and estrogenic activities and described the chemical compositions of its hydro-ethanolic (HE) extract. We used LC-MS/MS and GC-MS analyses to profile the phytochemical composition of the HE extract and to assess the analgesic and wound-healing effects of both the hydro-ethanolic (HE) and polyphenolic (LOP) extracts in vivo and in silico. The analgesic activity was studied using two methods: acetic acid and formalin injections in mice. The wound-healing activity was carried out over 25 days using a burn model in rats. In the in silico study, the polyphenols identified in the plant were docked in the active sites of three enzymes: casein kinase-1, cyclooxygenase-2, and glycogen synthase kinase-3β. The LC-MS/MS identified some phenolic compounds, mainly apigenin, catechin, and myricetin, and the GC-MS analysis revealed the presence of 19 volatile compounds with triazole, D-glucose, hydroxyphenyl, and D-Ribofuranose as the major compounds. The HE and LOP extracts showed significant decreases in abdominal writhes, and the higher licking time of the paw (57.67%) was observed using the LOP extract at 200 mg/kg. Moreover, both extracts showed high healing percentages, i.e., 99.31 and 92.88%, compared to the control groups, respectively. The molecular docking showed that myricetin, amentoflavone, apigenin, and catechin are the most active molecules against the three enzyme receptors. This study sheds light on the potential of L. officinalis Chaix as a source of natural products for pharmaceutical applications for analgesic purposes as well as their utility in promoting burn-healing activity.

Green tea epigallocatechin gallate suppresses 3T3-L1 cell growth via microRNA-143/MAPK7 pathways

Green tea epigallocatechin gallate (EGCG) and microRNA (miRNA) molecules modulate obesity. Nevertheless, it is still unknown whether EGCG modulates fat cell growth via miRNA-related signaling. In this study, white preadipocytes were used to examine whether the antimitogenic effect of EGCG on fat cells is regulated by the miR-143/MAPK7 pathway. We showed that EGCG upregulated the levels of miR-143, but not miR-155, in 3T3-L1 preadipocytes. Moreover, EGCG downregulated MAPK7 mRNA and protein levels time- and dose-dependently. MAPK7 expression increased during 3T3-L1 cell proliferation. miR-143 overexpression in the absence of EGCG mimicked the effects of EGCG to suppress preadipocyte growth and MAPK7 expression, whereas knockdown of miR-143 antagonized the EGCG-altered levels of miR-143, MAPK7, and pERK1/2 and reversed the EGCG-inhibited cell growth. These findings suggest that EGCG inhibits 3T3-L1 cell growth via miR-143/MAPK7 pathway.

Simultaneous UHPLC-MS Quantification of Catechins and Untargeted Metabolomic Profiling for Proof-of-Concept Authenticity Determination of Maytenus ssp. Samples

Due to the widespread use of Maytenus ilicifolia leaves in the treatment of gastric ulcers, herbal medicines derived from such species are distributed by the national health system in Brazil. A related species, Maytenus aquifolium, is also used for the same disorders, and both are popularly known as Espinheira-santa. Due to their popular use, the quality and efficiency of the herbal medicines derived from these species is an important public health issue. The purpose of this study was to develop and test an analytical method that could quantify the content of catechin and epicatechin in dry Maytenus spp. leaves and simultaneously obtain their chemical profile to determine authenticity of the leaf samples. Ultra-high performance liquid chromatography coupled to mass spectrometry (UHPLC-MS) was used to quantify these isomers, in the selected ion monitoring (SIM) mode, while simultaneously analyzing the extract in full-scan mode. This approach was successfully applied to the analysis of commercial and authentic samples of Maytenus spp. Fewer than half the samples presented the minimum epicatechin content of 2.8 mg per g of dry leaf mass, as specified in the 6th Brazilian Pharmacopoeia (2019) for M. ilicifolia. Furthermore, by using untargeted metabolomics, it was observed that the chemical profile of most the samples was not compatible with M. ilicifolia leaves, indicating the need for stricter quality control of this material. The method described herein could be used for this control; moreover, its concept could be adapted and used for an ample variety of medicinal plant products.

How procyanidin C1 sticks to collagen: The role of proline rings

Molecular interactions between proteins and polyphenols are responsible for many natural phenomena like colloidal turbidity, astringency, denaturation of enzymes and leather tanning. Although these phenomena are well known, there are open questions about the specific interactions involved in the complexation process. In this work, Molecular Dynamic (MD) simulations and the topology of the electron density analysis were used to study the interactions between the flavonoid procyanidin C1 and a collagen fragment solvated in water. Root mean square deviation; root mean square fluctuation and hydrogen bonds occupancy were examined after 50 ns. The interactions were also analyzed by means of the quantum theory of atoms in molecules. Our results show that the main interactions are hydrogen bonds between -OH groups of the polyphenol and CO groups of the peptide bond. Stacking interactions between proline rings and phenol rings, that is CH⋯π hydrogen bonds, also stabilize the dynamic structure of the complex.

Characterizing relationship between chemicals and in vitro bioactivities of teas made by six typical processing methods using a single Camellia sinensis cultivar, Meizhan

Processing method is considered as a major factor that affects biotransformation of phytochemicals in tea and leads to diverse flavor and bioactivity of tea. In the present work, six typical tea manufacturing processings were employed to compare the effect on chemical composition of teas through using leaves of the single tea cultivar – – Camellia sinensis var. Meizhan. And in vitro antioxidant activity, inhibition against α-glucosidase and three lipid metabolism enzymes of these teas were also investigated, the relationships among them were analyzed further. As fresh leaves were processed into six categories of teas, the content of total catechins (TCs) has decreased in varying degrees while theaflavins (TFs) has increased. The antioxidant capacity composite index (ACCI) from high to low were green tea, yellow tea, oolong tea, white tea, dark tea, and black tea with the range from 98.44 to 58.38, which dominated by the content of TCs. Furthermore, all categories of teas possessed an inhibition effect on the pancreatic lipase (PL), 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-COA reductase), lecithin cholesterol acyltransferase (LCAT), and α-glucosidase. The inhibition rate of PL and α-glucosidase appears to be positively influenced by TFs content (r =0.863, r =0.857, p < 0.05) while that of LCAT showed significant positive correlations with the content of tea polyphonels (TPs) (r = 0.902, p < 0.01). These results provide a better understanding of the relationships between processing method and chemical components of tea. It is suggested that various tea categories possess potential healthy effects which could serve as promising nutritional supplements.

Assessment of in vivo estrogenic and anti-inflammatory activities of the hydro-ethanolic extract and polyphenolic fraction of parsley (Petroselinum sativum Hoffm.)

ETHNOPHARMACOLOGICAL RELEVANCE

Since the dawn of time, medicinal and aromatic plants (AMPs) represent a precious heritage for humanity, especially in developing countries, who exploit their virtues in traditional pharmacopoeia to cope with health problems such as diabetes, kidney stones, ulcer, and digestive disorders. Petroselinum sativum Hoffm. belongs to Apiaceae family. It is traditionally used to treat arterial hypertension, diabetes, cardiac disease, renal disease, and recently reported as a plant endowed with a female anti-infertility effect.

AIM OF THE STUDY

This study aims to evaluate the in vivo effect of hydro-ethanolic extract and polyphenols of Petroselinum sativum Hoffm. on cholesterol, protein and estrogen levels, and characterize the chemical composition of polyphenolic fraction. In addition, acute toxicity and anti-inflammatory activity of tested extract was also investigated.

MATERIALS AND METHODS

Chemical composition of polyphenolic fraction was determined using High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD). First, toxicological investigations including sub-acute toxicity were performed by measuring animals' weights daily for four weeks. Afterwards, histopathological examination of livers and kidneys, and serum assay of ASAT and ALAT were also checked. Next, the acute in vivo anti-inflammatory study of the hydro-ethanolic extract and polyphenols of Petroselinum sativum Hoffm. versus Indomethacin was conducted. Furthermore, we evaluated the estrogenic effect of its hydro-ethanolic extract and the polyphenolic fraction following biochemical assays for the determination of proteins, cholesterol and estrogen levels.

RESULTS

The results revealed the presence of some phenolic compounds mainly ferulic acid, gallic acid and quercetin. Petroselinum sativum Hoffm. extracts also showed no evidence of hepatotoxicity nor nephrotoxicity, with remarkable anti-inflammatory activity, as well as a significant estrogenic effect compared to negative control.

CONCLUSION

This study provides a scope of the potential use of Petroselinum sativum Hoffm. extracts in counteracting female infertility issues.

Caralluma europaea (Guss.) N.E.Br.: Anti-Inflammatory, Antifungal, and Antibacterial Activities against Nosocomial Antibiotic-Resistant Microbes of Chemically Characterized Fractions

Caralluma europaea (Guss.) N.E.Br.: (C. europaea) is a wild medicinal plant belonging to the family Apocynaceae. It is commonly used in traditional medicines for treating several diseases. The present work aims to evaluate the anti-inflammatory, antibacterial, and antifungal potentials of C. europaea fractions including hydro ethanol (ET CE), n-butanol (But CE), and polyphenol (Poly CE). The chemical composition of hydroethanol, n-butanol, and polyphenol-rich fractions from C. europaea were determined using GC-MS after silylation. The anti-inflammatory effect of hydroethanol, n-butanol, and polyphenol-rich fractions was studied by carrageenan-induced paw edema. Antibacterial and antifungal activities of hydroethanol, n-butanol, and polyphenol-rich fractions against Gram-positive bacteria, Gram-negative bacteria, and yeasts were assessed using the disc diffusion and micro-dilution assays. The findings of the chemical characterization affirmed the presence of interesting bioactive compounds in C. europaea fractions. The polyphenol-rich fraction was the best inhibitor of edema by75.68% after 6 h of treatment. The hydroethanol fraction was the most active against both bacteria and yeasts. This study contributes to society as it provides potential bioactive compounds in C. europaea extract, which may help in fighting nosocomial antibiotic-resistant microbes.

Protective Effect of Chemically Characterized Polyphenol-Rich Fraction from Apteranthes europaea (Guss.) Murb. subsp. maroccana (Hook.f.) Plowes on Carbon Tetrachloride-Induced Liver Injury in Mice

Apteranthes europaea (Guss.) Murb. subsp. maroccana (Hook.f.) Plowes (A. europaea) is a medicinal plant widely used in traditional medicines to treat various diseases including hepatic pathogenesis. This study was conducted to evaluate the protective effect of chemically characterized polyphenol-rich fraction from A. europaea on carbon tetrachloride-induced liver injury in mice. The chemical characterization of A. europaea polyphenol-rich fraction was carried out using HPLC-DAD (high-performance liquid chromatography (HPLC) with a diode-array detector (DAD)). Carbon tetrachloride (CCl4) was used to induce liver injuries in mice as described in previous works. A polyphenol-rich fraction from A. europaea was used at a dose of 50 mg/Kg to study its hepatoprotective effect. Next, histopathological and biochemical alterations were investigated. The HPLC analysis revealed the presence of several phenolic compounds: gallic acid, methyl gallate, rutin, ferulic acid, and resorcinol. Regarding the mice treated with a polyphenol-rich fraction from A. europaea up to 50 mg/Kg and carbon tetrachloride, no significant biochemical nor histological alterations occurred in their liver; meanwhile, serious biochemical and histopathological changes were noted for liver recovered from the mice treated with carbon tetrachloride only. In conclusion, A. europaea extract is a promising source of hepatoprotective agents against toxic liver injury.

Aliqahtani A, M. Noman O, A. Nasr F, Conte R, Calarco A, Bousta D. Subacute Assessment of the Toxicity and Antidepressant-Like Effects of Origanum Majorana L. Polyphenols in Swiss Albino Mice

Origanum majorana L. is a plant commonly used in folk medicine to treat depression and several neurological disorders. This study aims to evaluate the antidepressant-like effect of the Origanum majorana L. polyphenols (OMP) obtained from the aerial parts using two different depression model tests: The forced swimming test (FST) and the tail suspension test (TST) in Swiss albino mice. The experiments were performed on days 1, 7, 14, and 21 with daily administration of different treatments. Two different doses were chosen for this study (50 and 100 mg/kg), and paroxetine was used as a positive control. Immobility as a consequence of the depression state was significantly reduced following the treatment with OMP, indicating an antidepressant effect. A subacute toxicity study was also performed following the Organization for Economic Co-operation and Development (OECD) Guidelines (407), showing no sign of toxicity for the studied doses. The phytochemical screening revealed the presence of 12 components, all belonging to polyphenols: Arbutin, rosmarinic acid, ursolic acid, quercetin-3-O-glucoside, quercetin-7-O-glucuronic acid, luteolin-7-O-glucoside, kaempferol-3-0-glucuronic acid, Kaempferol-3-0-pentose, caffeic acid, catechin, quercetin, and rutin. These findings suggest that O. majorana has interesting antidepressant-like properties, which deserve further investigation.

Modulation of Nutritional and Biochemical Properties of Wheat Grains Infected by Blast Fungus Magnaporthe oryzae Triticum Pathotype

Wheat blast disease caused by the Magnaporthe oryzae Triticum (MoT) pathotype exerts a significant impact on grain development, yield, and quality of the wheat. The aim of this study was to investigate morphological, physiological, biochemical, and nutritional properties of wheat cv. BARI Gom 24 under varying levels of blast disease severity in wheat spikes. Grain morphology, volume, weight, and germination of the infected grains were significantly affected by MoT. Biochemical traits specifically grain N, Ca, Mg, and Fe content significantly increased (up to threefold; p > 0.05), but organic carbon, Cu, Zn, B, and S content in wheat grains significantly decreased with increased severity of MoT infection. The grain crude protein content was about twofold higher (up to 18.5% in grain) in severely blast-infected grains compared to the uninfected wheat (9.7%). Analysis of other nutritional properties such as secondary metabolites revealed that total antioxidant activity, flavonoid, and carotenoid concentrations remarkably decreased (up to threefold) with increasing severity of blast infestation in wheat grain. Grain moisture, lipid, and ash content were slightly increased with the increase in blast severity. However, grain K and total phenolic concentration were increased at a certain level of blast infestation and then reduced with increase in MoT infestation.

Radiation Chemical Investigation of Antioxidant Activity of Biologically Important Compounds from Plant Materials

Radiation chemical modeling of redox reactions of biologically active compounds from plant materials showed that coumarins possess strong antiradical properties. Data confirming the radioprotective properties of these compounds were obtained. Antioxidant activity has been shown for specific medicinal plant extracts-Melilotus officinalis and Ledum palustre cormus. The radiation chemical transformations of coumarins revealed that an unsubstituted coumarin has greater radioprotective activity.

Effects of tannase-converted green tea extract on skeletal muscle development

BACKGROUND

The aim of this study was to investigate the effect of tannase-converted green tea extract with a high (-)-epicatechin (EC), (-)-epigallocatechin (EGC), and gallic acid (GA) content on myotube density and fusion in normal and oxidative stress-induced C2C12 skeletal muscle cells. Although the use of green tea extract is considered beneficial, cellular and molecular mechanisms of action of tannase-converted green tea extracts that are used as potential muscle growth materials have not been thoroughly studied.

METHODS

This study used histological analysis and molecular biology techniques, and compared the results with those for AMPK activator 5-aminoimidazole-4-carboxamide-1-β-D-ribonucleoside (AICAR) and green tea extracts.

RESULTS

The myotube density of normal and oxidative stress-induced C2C12 cells was significantly higher in the tannase-converted green tea extract-treated group than that observed in the other groups (normal cells: P < 0.01; oxidative stress-induced cells: P < 0.05). In addition, tannase-converted green tea extract and green tea extract treatments significantly upregulated the genetic expression of myogenin, Myf5, and MyoD (P < 0.05). The levels of AMP-activated protein kinase-α (AMPKα) and muscle RING-finger protein-1 (MuRF-1) in the tannase-converted green tea extract group were higher than those in the AICAR and green tea extract groups (P < 0.05).

CONCLUSIONS

Taken together, our findings describe that the high levels of EC, EGC, and GA in the tannase-converted green tea extract are attributable to the morphological changes in C2C12 cells and intercellular signaling pathways. Therefore, tannase-converted green tea extract can be used in the treatment of sarcopenia.

Effects of flavonoids on tongue squamous cell carcinoma

Squamous cell carcinoma (SCC) of the tongue is associated with tobacco use, alcohol abuse, and human papillomavirus (HPV) infections. While clinical outcomes have recently improved for HPV-positive patients in general, 50% of patients suffering from tongue cancer die within 5 years of being diagnosed. Flavonoids are secondary plant metabolites with a wide range of biological activities including antioxidant, anti-inflammatory, and anticancer activities. Flavonoids have generated high interest as therapeutic agents owing to their low toxicity and their effects on a large variety of cancer cell types. In this literature review, we evaluate the actions of flavonoids on SCC of the tongue demonstrated in both in vivo and in vitro models.

Quantification of ascorbyl adducts of epigallocatechin gallate and gallocatechin gallate in bottled tea beverages

Catechins are the major bioactive compounds existing in tea leaves (Camellia sinensis). Dehydroascorbic acid is (DHAA) a reactive dicarbonyl species and previous studies have demonstrated that catechins could effectively trap DHAA to form ascorbyl adducts of catechins, especially epigallocatechin gallate (EGCG). Since catechins in the aqueous solution are unstable due to their structural features, ascorbic acid (AA) is usually added to bottled tea beverages to protect catechins. However, whether ascorbyl adducts of catechins are formed in bottled tea beverages remains unclear. In this study, formation of ascorbyl adducts of EGCG increased along with increased incubation time when EGCG and AA were dissolved in the aqueous solution. Next, 6C-DHAA-EGCG and 8C-DHAA-EGCG were detected in both green tea and oolong tea beverages, and their concentrations ranged from 0.23 to 1.95 µM and 0.28 to 1.97 µM, respectively. Furthermore, an 8C-ascorbyl adduct derived from gallocatechin gallate was also found in some tea beverages.

Diabetes and Alzheimer's Disease: Can Tea Phytochemicals Play a Role in Prevention?

Dementia and diabetes mellitus are prevalent disorders in the elderly population. While recognized as two distinct diseases, diabetes has more recently recognized as a significant contributor to risk for developing dementia, and some studies make reference to type 3 diabetes, a condition resulting from insulin resistance in the brain. Alzheimer's disease, the most common form of dementia, and diabetes, interestingly, share underlying pathological processes, commonality in risk factors, and, importantly, pathways for intervention. Tea has been suggested to possess potent antioxidant properties. It is rich in phytochemicals including, flavonoids, tannins, caffeine, polyphenols, boheic acid, theophylline, theobromine, anthocyanins, gallic acid, and finally epigallocatechin-3-gallate, which is considered to be the most potent active ingredient. Flavonoid phytochemicals, known as catechins, within tea offer potential benefits for reducing the risk of diabetes and Alzheimer's disease by targeting common risk factors, including obesity, hyperlipidemia, hypertension, cardiovascular disease, and stroke. Studies also show that catechins may prevent the formation of amyloid-β plaques and enhance cognitive functions, and thus may be useful in treating patients who have Alzheimer's disease or dementia. Furthermore, other phytochemicals found within tea offer important antioxidant properties along with innate properties capable of modulating intracellular neuronal signal transduction pathways and mitochondrial function.

Polyphenols-rich extract from Pleurotus eryngii with growth inhibitory of HCT116 colon cancer cells and anti-inflammatory function in RAW264.7 cells

Edible mushrooms are rich sources of bioactive components. In this study, a polyphenol-rich extract, designated as PPEP, was isolated from an edible mushroom, Pleurotus eryngii. Using ultra high performance liquid chromatograph combined with triple time-of-flight mass spectrometry (UPLC-TOF/MS/MS), gallic acid monohydrate, 3-(3,4-dihydroxyphenyl)-propionic acid, methyl gallate, syringic acid, ellagic acid and catechin were identified in PPEP. This phenolic-rich extract PPEP exhibited anti-inflammatory effect in lipopolysaccharide-stimulated RAW264.7 macrophages by inhibiting the overproduction of pro-inflammatory mediators including nitric oxide (NO) and reactive oxygen species (ROS). It was demonstrated that the anti-inflammatory effects of PPEP were associated with the inhibition of iNOS expression, suppression of p-IκB protein expression and inhibition of NF-κB and IκB mRNA expression. Next, the inhibitory effect of PPEP against human colon cancer cells was also determined. PPEP suppressed cell proliferation of human colon cancer HCT116 cells in a dose- and time-dependent fashion, while it showed no inhibitory effect on normal human colonic myofibroblasts CCD-18Co cells at the same tested concentrations (0-200 μg mL^-1). Moreover, PPEP induced cell cycle arrest and led to extensive cellular apoptosis in human colon cancer cells, which was associated with the downregulation of cell cycle-related signaling protein, e.g. cyclin B and cyclin E, and the upregulation of apoptosis-related signaling protein caspase-3 and cleaved caspase-3. Overall, our results provided a basis for using PPEP as a promising preventive agent against inflammatory disease and colon cancer.

Recent advances to accelerate re-endothelialization for vascular stents

Cardiovascular diseases are considered as one of the serious diseases that leads to the death of millions of people all over the world. Stent implantation has been approved as an easy and promising way to treat cardiovascular diseases. However, in-stent restenosis and thrombosis remain serious problems after stent implantation. It was demonstrated in a large body of previously published literature that endothelium impairment represents a major factor for restenosis. This discovery became the driving force for many studies trying to achieve an optimized methodology for accelerated re-endothelialization to prevent restenosis. Thus, in this review, we summarize the different methodologies opted to achieve re-endothelialization, such as, but not limited to, manipulation of surface chemistry and surface topography.

Epigallocatechin Gallate Nanodelivery Systems for Cancer Therapy

Cancer is one of the leading causes of morbidity and mortality all over the world. Conventional treatments, such as chemotherapy, are generally expensive, highly toxic and lack efficiency. Cancer chemoprevention using phytochemicals is emerging as a promising approach for the treatment of early carcinogenic processes. (−)-Epigallocatechin-3-gallate (EGCG) is the major bioactive constituent in green tea with numerous health benefits including anti-cancer activity, which has been intensively studied. Besides its potential for chemoprevention, EGCG has also been shown to synergize with common anti-cancer agents, which makes it a suitable adjuvant in chemotherapy. However, limitations in terms of stability and bioavailability have hampered its application in clinical settings. Nanotechnology may have an important role in improving the pharmacokinetic and pharmacodynamics of EGCG. Indeed, several studies have already reported the use of nanoparticles as delivery vehicles of EGCG for cancer therapy. The aim of this article is to discuss the EGCG molecule and its associated health benefits, particularly its anti-cancer activity and provide an overview of the studies that have employed nanotechnology strategies to enhance EGCG’s properties and potentiate its anti-tumoral activity.

The synthesis of boronic-imine structured compounds and identification of their anticancer, antimicrobial and antioxidant activities

Boronic acid compounds with different substituted groups were handled to synthesize various ligands encoded as B1, B2, B3, B4, B5, B6, B7 and B8. B5 and B7 were tested for the cytotoxic activity against the prostate cancer cells and it was found that the cell viability of cancer cells was decreased while most of the healthy cells could still be viable. 5 µM solutions of B5 and B7 decreased the cell viability to 33% and 44% whereas healthy cells were 71% and 95%, respectively, after treatment. Antimicrobial properties were explored against the bacterial and fungal microorganisms with B1, B5 and B7. The inhibition zones were evaluated for all boronic structures, and the growth inhibition zones were determined in a range of 7–13 mm diameter for different microorganism species. Staphylococcus aureus was the common microorganism that three boronic compounds with imine ligands showed the activity. Antioxidant features of B2, B3, B4, B5, B6, B7 and B8 were investigated by different processes such as Beta-carotene bleaching (BCB), 2,2-diphenyl picryl hydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and CUPric reducing antioxidant capacity (CUPRAC) methods. Significant antioxidant activity was achieved by the phenyl boronic based ligands and these compounds demonstrated as much activity as standards (α-Toc and BHT). In addition, all structures were applied properly without any decomposition during the experiments. They were rather stable both in aqueous media and solid state.

Preincubation with green tea polyphenol extract is beneficial for attenuating sperm injury caused by freezing-thawing in swine

Polyphenols (PFs) extracted from green tea, known to be potent anti-oxidants, have been reported to be effective in increasing the motility and viability of mammalian sperm, preserved in a liquid form. Therefore, we tested whether PFs might also be effective for maintaining the integrity of frozen-thawed boar spermatozoa. Ejaculates, collected from Clawn miniature pigs, were diluted in a semen extender containing various amounts of PFs (0, 0.01, 0.05, 0.1 and 0.2% w/v) and then stored at 15°C overnight. The semen samples were processed, using the straw freezing procedure, and then frozen in liquid nitrogen. After rapid thawing at 40°C, the spermatozoa were subjected to several assays to evaluate semen quality. Spermatozoa frozen in a medium containing 0.01% w/v PFs exhibited significantly (P < 0.05) higher degrees of post-thawed viability and acrosomal integrity than those stored in the absence of PFs. However, no change in the mitochondrial activity was noted between the two groups. The inclusion of 0.01% PFs in the semen extender was significantly (P < 0.05) effective in increasing both the rates of monospermic oocyte formation and of blastocyst formation. These findings indicate that preincubation with the semen extender, containing 0.01% PFs prior to freezing, exerts a protective effect on boar sperm by preventing injuries associated with freezing-thawing.

Green tea catechins alone or in combination alter functional parameters of human neutrophils via suppressing the activation of TLR-4/NFκB p65 signal pathway

The purpose of this study was to evaluate the potential of a mixture containing the four main catechins found in green tea, as well it separately, as modulators of the functional parameters of human neutrophils. The cells were obtained from peripheral blood of healthy individuals isolated and cultured with a mix: 30 μM of EGCG, 3 μM of EGC, 2 μM of ECG and 1.4 μM of EC, as well as each one alone. We evaluated the cytotoxicity of catechins, production of several reactive oxygen species (ROS), antioxidant enzymes (SOD, CAT, GPx and GR), Nrf2, TLR4/IKK/NFκB, CD11b mRNA levels, intracellular calcium release, chemotactic and phagocytic capacity, myeloperoxidase (MPO), and G6PDH activities, hypochlorous acid (HOCl) and pro-inflammatory cytokines release, protein levels of TLR4, p38 MAPK, iNOS and p-65 NFκB. The actions of the catechins were evidenced by the reduction in inflammatory parameters, including the suppression of TLR4, NFκB and iNOS protein expression, decreased release of TNF-α, IL-1β and IL-6, migration capacity, MPO activity and HOCl production and the suppression of ROS, nitric oxide and peroxynitrite production, while inducing antioxidant enzyme activities and Nrf2 mRNA levels, phagocytic capacity and calcium release. Our results demonstrate that catechins present marked immunomodulatory actions, either alone or in combination.

Non-Nutrient, Naturally Occurring Phenolic Compounds with Antioxidant Activity for the Prevention and Treatment of Periodontal Diseases

One of the main factors able to explain the pathophysiological mechanism of inflammatory conditions that occur in periodontal disease is oxidative stress. Given the emerging understanding of this relationship, host-modulatory therapies using antioxidants could be interesting to prevent or slow the breakdown of soft and hard periodontal tissues. In this context, non-nutrient phenolic compounds of various foods and plants have received considerable attention in the last decade. Here, studies focusing on the relationship between different compounds of this type with periodontal disease have been collected. Among them, thymoquinone, coenzyme Q (CoQ), mangiferin, resveratrol, verbascoside and some flavonoids have shown to prevent or ameliorate periodontal tissues damage in animal models. However evidence regarding this effect in humans is poor and only limited to topical treatments with CoQ and catechins. Along with animal experiments, in vitro studies indicate that possible mechanisms by which these compounds might exert their protective effects include antioxidative properties, oxygen and nitrogen scavenging abilities, and also inhibitory effects on cell signaling cascades related to inflammatory processes which have an effect on RNS or ROS production as well as on antioxidant defense systems.

Anti-wrinkle Effects of Water Extracts of Teas in Hairless Mouse

Tea flavonoids and polyphenols are well known for their extraordinary antioxidant activity which is considered important for anti-aging processes in animals. This study evaluated the anti-wrinkle effects of three different kinds of tea (Camellia sinensis) water extracts (CSWEs) including green, white, and black teas using a photoaged hairless mouse model. Data showed that the CSWE-treatment greatly improved skin conditions of mice suffering from UVB-induced photoaging, based on the parameters including the skin erythema index, moisture capacity, and transepidermal water loss. In addition, the wrinkle measurement and image analysis of skin replicas indicated that CSWEs remarkably inhibited wrinkle formation. In histological examination, the CSWE-treated mice exhibited diminished epidermal thickness and increased collagen and elastic fiber content, key signatures for skin restoration. Furthermore, the reduced expression of MMP-3, a collagen-degradative enzyme, was observed in the skin of CSWE-treated animals. Interestingly, comparative data between green, white, and black tea indicated that the anti-wrinkle activity of white tea and black tea is equally greater than that of green tea. Taken together, these data clearly demonstrated that CSWEs could be used as an effective anti-wrinkle agent in photoaged animal skin, implying their extended uses in therapeutics.

Green tea (-)-epigallocatechin gallate suppresses IGF-I and IGF-II stimulation of 3T3-L1 adipocyte glucose uptake via the glucose transporter 4, but not glucose transporter 1 pathway

This study investigated the pathways involved in EGCG modulation of insulin-like growth factor (IGF)-stimulated glucose uptake in 3T3-L1 adipocytes. EGCG inhibited IGF-I and IGF-II stimulation of adipocyte glucose uptake with dose and time dependencies. EGCG at 20μM for 2h decreased IGF-I- and IGF-II-stimulated glucose uptake by 59% and 64%, respectively. Pretreatment of adipocytes with antibody against the EGCG receptor (also known as the 67-kDa laminin receptor; 67LR), prevented the effects of EGCG on IGF-increased glucose uptake, but pretreatment with normal rabbit immunoglobulin did not. This suggests that the 67LR mediates the anti-IGF effect of EGCG on adipocyte glucose uptake. Further analysis indicated EGCG, IGF-I, and IGF-II did not alter total levels of GLUT1 or GLUT4 protein. However, EGCG prevented the IGF-increased GLUT4 levels in the plasma membrane and blocked the IGF-decreased GLUT4 levels in low-density microsomes. Neither EGCG nor its combination with IGF altered GLUT1 protein levels in the plasma membrane and low-density microsomes. EGCG also suppressed the IGF-stimulated phosphorylation of IGF signaling molecules, PKCζ/λ, but not AKT and ERK1/2, proteins. This study suggests that EGCG suppresses IGF stimulation of 3T3-L1 adipocyte glucose uptake through inhibition of the GLUT4 translocation, but not through alterations of the GLUT1 pathway.

Gallic acid tailoring surface functionalities of plasma-polymerized allylamine-coated 316L SS to selectively direct vascular endothelial and smooth muscle cell fate for enhanced endothelialization

The creation of a platform for enhanced vascular endothelia cell (VEC) growth while suppressing vascular smooth muscle cell (VSMC) proliferation offers possibility for advanced coatings of vascular stents. Gallic acid (GA), a chemically unique phenolic acid with important biological functions, presents benefits to the cardiovascular disease therapy because of its superior antioxidant effect and a selectivity to support the growth of ECs more than SMCs. In this study, GA was explored to tailor such a multifunctional stent surface combined with plasma polymerization technique. On the basis of the chemical coupling reaction, GA was bound to an amine-group-rich plasma-polymerized allylamine (PPAam) coating. The GA-functionalized PPAam (GA-PPAam) surface created a favorable microenvironment to obtain high ECs and SMCs selectivity. The GA-PPAam coating showed remarkable enhancement in the adhesion, viability, proliferation, migration, and release of nitric oxide (NO) of human umbilical vein endothelial cells (HUVECs). The GA-PPAam coating also resulted in remarkable inhibition effect on human umbilical artery smooth muscle cell (HUASMC) adhesion and proliferation. These striking findings may provide a guide for designing the new generation of multifunctional vascular devices.

Construction of polyfunctional coatings assisted by gallic acid to facilitate co-immobilization of diverse biomolecules

Designing a multifunctional surface based on the coimmobilization of two or more diverse biomolecules with synergic action is very important in certain cases. In this work, a facile method by two-step aimed to construct a polyfunctional coating containing -COOH, -NH2, and phenol/quinine groups was reported. The first-step was to introduce amine groups onto target modified-surface by coating with plasma polymerized allylamine (PPAam), followed by the second-step conjugation of gallic acid (3,4,5-trihydroxybenzoic acid) onto the PPAam surface. The density of -COOH, -NH2, and phenol/quinone groups could be regulated easily by adjusting the reaction time of GA conjugation, making it possible to coimmobilize two or three diverse molecules. This has been shown by the successful coimmobilization of anti-CD34 antibody and vascular endothelial growth factor (VEGF). The surface coimmobilized with the anti-CD34 antibody and VEGF presented significant enhancement in the capture of endothelial progenitor cells (EPCs) and the growth of human umbilical vein endothelial cells (HUVECs). These data suggest the huge potential of such polyfunctional coating for tailoring the desired interfacial properties of materials through selectively conjugating two or more diverse bioactive molecules with synergic action.

Effect of Epigallocatechin Gallate on shear bond strength of composite resin to bleached enamel: an in vitro study

Objectives

The aim of this study was to determine the effect of epigallocatechin gallate (EGCG) on the shear bond strength of composite resin to bleached enamel.

Materials and Methods

Ninety enamel surfaces of maxillary incisors were randomly divided into 9 groups as follows: G1: control (no bleaching); G2: bleaching; G3: bleaching and storage for seven days; G4 - 6: bleaching and application of 600, 800 and 1,000 µmol of EGCG-containing solution for 10 minutes, respectively; G7 - 9: bleaching and application of 600, 800 and 1,000 µmol of EGCG-containing solution for 20 minutes, respectively. The specimens were bleached with 30% hydrogen peroxide gel and a composite resin cylinder was bonded on each specimen using a bonding agent. Shear bond strength of the samples were measured in MPa. Data was analyzed using the two-way ANOVA and Tukey HSD tests (α = 0.05).

Results

The maximum and minimum mean shear bond strength values were observed in G1 and G2, respectively. Time and concentration of EGCG showed no significant effects on bond strength of the groups (p > 0.05). Multiple comparison of groups did not reveal any significant differences between the groups except for G2 and all the other groups (p < 0.05).

Conclusions

There is a significant decrease in bond strength of composite resin to enamel immediately after bleaching. A delay of one week before bonding and the use of EGCG increased bond strength of composite resin to bleached enamel.

Characterization of binding interactions of (-)-epigallocatechin-3-gallate from green tea and lipase

Understanding the interaction of (-)-epigallocatechin-3-gallate (EGCG) and lipase is important for understanding EGCG's inhibition of lipase. In this paper, the interaction of EGCG and porcine lipase was characterized by fluorescence spectroscopy, circular dichroism (CD), isothermal titration calorimetry, and molecular docking. EGCG might act as a noncompetitive pancreatic lipase inhibiter. EGCG bound to lipase with affinity of K(a) = 2.70 × 10⁴ L mol⁻¹. Thermodynamic features suggested that the interaction process was spontaneous, with hydrogen bonds and electrostatic force perhaps primarily responsible for the interaction, with 1:1 interaction of lipase and EGCG. CD studies indicated conformation change of lipase on binding to EGCG. Furthermore, docking results supported experimental findings and revealed hydrogen-bonding interaction with Val21, Glu188, and Glu220. This noncovalent bonding between EGCG and lipase alters the molecular conformation of lipase, which decreases the enzyme catalytic activity. This study will help further understand the antiobesity mechanisms of green tea.

Volatile Fraction Composition and Total Phenolic and Flavonoid Contents of Elionurus hensii—Antioxidant Activities of Essential Oils and Solvent Extracts

The objective of this study was to characterize Elionurus hensii in terms of the chemical composition of its essential oil and volatile fractions, the total phenolic and flavonoid contents of solvent extracts and antioxidative activity. Analysis of E. hensii essential oil samples from Congo was carried out using Gas Chromatography (GC) and Gas Chromatography-Mass Spectrometry (MS). The essential oil of the aerial parts consisted predominantly of oxygenated monoterpene compounds, of which the main components were menthane alcohol stereoisomers, whereas the essential oil of the root was characterized by a high content of oxygenated sesquiterpenes, the main component of which was aristolone. The amounts of total phenolics and flavonoids in the solvent extracts (dichloromethane, ethyl acetate and methanol) were determined spectrometrically. The essential oil did not exhibit significant antioxidant activity in terms of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid (ABTS•+) scavenging ability, and exhibited only slight Fe3+ reducing ability. In contrast, the antioxidant activity of the solvent extracts of the aerial parts increased in the order ethyl acetate > methanol > dichloromethane, and that of the solvent extracts of the root increased in the order methanol > ethyl acetate > dichloromethane. Finally, a relationship was observed between the antioxidant activity and the total phenolic and flavonoid levels of the extract.