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1.
Food Chem ; 463(Pt 1): 141085, 2025 Jan 15.
Article in English | MEDLINE | ID: mdl-39243619

ABSTRACT

The influence of oxygen on the thermal treatment (TT) of secondary metabolite-enriched extracts (SMEEs) from Tórtola beans and procyanidin C1 (PC1) on the inhibition of advanced glycation end products (AGEs) generation in proteins was investigated. SMEE was incubated at 4 °C (control) or thermally treated at 60 °C for 2 h, at either 0 % O2 (I) or 20 % O2 (II). Treatments I and II increased the content of procyanidin dimers B2. Treatment II was more effective than the control or treatment I in preventing homocysteine oxidation and AGEs generation. TT of PC1 at 0 % or 20 % O2 generated procyanidin dimers and tetramers. PC1 TT at 20 % O2 exhibited higher oxidation potentials and lower IC50 values of fluorescent AGEs than those of controls or TT at 0 % O2. These findings indicate that SMEE from Tórtola beans after treatment II changes the degree of polymerization and oxidation procyanidins, thereby increasing their antiglycation activity.


Subject(s)
Antioxidants , Biflavonoids , Glycation End Products, Advanced , Hot Temperature , Oxidation-Reduction , Phaseolus , Plant Extracts , Proanthocyanidins , Proanthocyanidins/chemistry , Proanthocyanidins/pharmacology , Glycation End Products, Advanced/chemistry , Glycation End Products, Advanced/metabolism , Antioxidants/chemistry , Antioxidants/pharmacology , Biflavonoids/pharmacology , Biflavonoids/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Phaseolus/chemistry , Catechin/chemistry , Catechin/pharmacology , Glycosylation , Chile
2.
Braz J Biol ; 84: e283740, 2024.
Article in English | MEDLINE | ID: mdl-39230082

ABSTRACT

More catechins are found in green tea than in any other type of tea, with its predominant production taking place in Asian nations. Consumption of green tea has been strongly correlated with a reduced risk of many diseases. This study introduces a new, efficient, and reliable method for extracting total catechins using ultra-high-performance liquid chromatography coupled with an ID-X-Orbitrap Mass spectrometer (UHPLC-IDX-Orbitrap-MS). The method was then applied to quantify the catechin content in green tea, yielding results comparable to previously published studies. Among the various sources of green tea analyzed, the lowest average catechin content was observed in Vietnam, Japan (2: Matcha), and Morocco, ranging between 346 and 322 mg/L. Conversely, the highest average catechin content (between 424 and 422 mg/L) was found in Sri Lanka and Japan (1: Sencha). For the remaining green tea extracts, the catechin levels ranged from 367 to 410 mg/L, exhibiting similar values. These findings demonstrate the high reproducibility of the proposed extraction procedure, with a relative standard deviation (RSD) error of less than 15% for the catechin standard. Additionally, the limit of detection for catechins was determined to be 1 ng mL-1. This study serves as a pilot investigation for extracting catechins from various green tea sources. Future research will focus on identifying all active compounds present. Furthermore, it is worth noting that this study aligns with the goals set forth in Saudi Vision 2030, which aims to diversify the country's economy and promote scientific advancements in various fields, including healthcare and agriculture.


Subject(s)
Catechin , Mass Spectrometry , Plant Leaves , Tea , Catechin/analysis , Catechin/isolation & purification , Chromatography, High Pressure Liquid/methods , Tea/chemistry , Mass Spectrometry/methods , Reproducibility of Results , Plant Leaves/chemistry , Plant Extracts/chemistry , Plant Extracts/analysis
3.
Food Res Int ; 194: 114918, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39232538

ABSTRACT

Polyphenolic compounds are common constituents of human and animal diets and undergo extensive metabolism by the gut microbiota before entering circulation. In order to compare the transformations of polyphenols from yerba mate, rosemary, and green tea extracts in the gastrointestinal tract, simulated gastrointestinal digestion coupled with colonic fermentation were used. For enhancing the comparative character of the investigation, colonic fermentation was performed with human, pig and rat intestinal microbiota. Chemical analysis was performed using a HPLC system coupled to a diode-array detector and mass spectrometer. Gastrointestinal digestion diminished the total amount of phenolics in the rosemary and green tea extracts by 27.5 and 59.2 %, respectively. These reductions occurred mainly at the expense of the major constituents of these extracts, namely rosmarinic acid (-45.7 %) and epigalocatechin gallate (-60.6 %). The yerba mate extract was practically not affected in terms of total phenolics, but several conversions and isomerizations occurred (e.g., 30 % of trans-3-O-caffeoylquinic acid was converted into the cis form). The polyphenolics of the yerba mate extract were also the least decomposed by the microbiota of all three species, especially in the case of the human one (-10.8 %). In contrast, the human microbiota transformed the polyphenolics of the rosemary and green extracts by 95.9 and 88.2 %, respectively. The yerba mate-extract had its contents in cis 3-O-caffeoylquinic acid diminished by 78 % by the human microbiota relative to the gastrointestinal digestion, but the content of 5-O-caffeoylquinic acid (also a chlorogenic acid), was increased by 22.2 %. The latter phenomenon did not occur with the rat and pig microbiota. The pronounced interspecies differences indicate the need for considerable caution when translating the results of experiments on the effects of polyphenolics performed in rats, or even pigs, to humans.


Subject(s)
Colon , Depsides , Digestion , Fermentation , Ilex paraguariensis , Plant Extracts , Polyphenols , Rosmarinic Acid , Rosmarinus , Animals , Humans , Plant Extracts/metabolism , Rosmarinus/chemistry , Rats , Ilex paraguariensis/chemistry , Swine , Depsides/metabolism , Depsides/analysis , Polyphenols/metabolism , Polyphenols/analysis , Colon/metabolism , Colon/microbiology , Male , Cinnamates/metabolism , Cinnamates/analysis , Gastrointestinal Microbiome , Tea/chemistry , Quinic Acid/analogs & derivatives , Quinic Acid/metabolism , Quinic Acid/analysis , Catechin/analogs & derivatives , Catechin/metabolism , Catechin/analysis , Chromatography, High Pressure Liquid , Camellia sinensis/chemistry
4.
Int J Mol Sci ; 25(16)2024 Aug 09.
Article in English | MEDLINE | ID: mdl-39201369

ABSTRACT

Photodynamic therapy (PDT) treats nonmelanoma skin cancer. PDT kills cells through reactive oxygen species (ROS), generated by interaction among cellular O2, photosensitizer and specific light. Protoporphyrin IX (PpIX) is a photosensitizer produced from methyl aminolevulinate (MAL) by heme group synthesis (HGS) pathway. In PDT-resistant cells, PDT efficacy has been improved by addition of epigallocatechin gallate (EGCG). Therefore, the aim of this work is to evaluate the effect of EGCG properties over MAL-TFD and PpIX production on A-431 cell line. EGCG's role over cell proliferation (flow cytometry and wound healing assay) and clonogenic capability (clonogenic assay) was evaluated in A-431 cell line, while the effect of EGCG over MAL-PDT was determined by cell viability assay (MTT), PpIX and ROS detection (flow cytometry), intracellular iron quantification and gene expression of HGS enzymes (RT-qPCR). Low concentrations of EGCG (<50 µM) did not have an antiproliferative effect over A-431 cells; however, EGCG inhibited clonogenic cell capability. Furthermore, EGCG (<50 µM) improved MAL-PDT cytotoxicity, increasing PpIX and ROS levels, exerting a positive influence on PpIX synthesis, decreasing intracellular iron concentration and modifying HGS enzyme gene expression such as PGB (upregulated) and FECH (downregulated). EGCG inhibits clonogenic capability and modulates PpIX synthesis, enhancing PDT efficacy in resistant cells.


Subject(s)
Catechin , Cell Proliferation , Heme , Photosensitizing Agents , Protoporphyrins , Reactive Oxygen Species , Catechin/analogs & derivatives , Catechin/pharmacology , Protoporphyrins/pharmacology , Protoporphyrins/metabolism , Humans , Heme/metabolism , Reactive Oxygen Species/metabolism , Photosensitizing Agents/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Photochemotherapy/methods , Cell Survival/drug effects , Aminolevulinic Acid/pharmacology , Aminolevulinic Acid/analogs & derivatives
5.
Molecules ; 29(12)2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38930808

ABSTRACT

In this study, a beverage made from a combination of Agave sap (AS) and prickly pear juice (PPJ) was analyzed for its nutrients and bioactive and potentially health-promoting compounds. The beverage was evaluated for its ability to act as an antioxidant, regulate glycemic properties, and undergo gut bacterial fermentation in vitro. The major mono- and oligosaccharides present in the beverage were galacturonic acid (217.74 ± 13.46 mg/100 mL), rhamnose (227.00 ± 1.58 mg/100 mL), and fructose (158.16 ± 8.86 mg/mL). The main phenolic compounds identified were protocatechuic acid (440.31 ± 3.06 mg/100 mL) and catechin (359.72 ± 7.56 mg/100 mL). It was observed that the beverage had a low glycemic index (<40) and could inhibit digestive carbohydrases. The combination of ingredients also helped to reduce gas production during AS fermentation from 56.77 cm3 to 15.67 cm3. The major SCFAs produced during fermentation were butyrate, acetate, and propionate, with valerate being produced only during the late fermentation of the AS. This beverage is rich in bioactive compounds, such as polyphenols and dietary fiber, which will bring health benefits when consumed.


Subject(s)
Agave , Antioxidants , Fruit and Vegetable Juices , Agave/chemistry , Fruit and Vegetable Juices/analysis , Antioxidants/chemistry , Antioxidants/pharmacology , Antioxidants/analysis , Fermentation , Hydroxybenzoates/analysis , Polyphenols/analysis , Polyphenols/chemistry , Pyrus/chemistry , Phenols/analysis , Phenols/chemistry , Rhamnose/analysis , Rhamnose/chemistry , Catechin/analysis , Catechin/chemistry , Catechin/analogs & derivatives , Hexuronic Acids
6.
Molecules ; 29(12)2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38930937

ABSTRACT

Polyphenols from agro-food waste represent a valuable source of bioactive molecules that can be recovered to be used for their functional properties. Another option is to use them as starting material to generate molecules with new and better properties through semi-synthesis. A proanthocyanidin-rich (PACs) extract from avocado peels was used to prepare several semi-synthetic derivatives of epicatechin by acid cleavage in the presence of phenol and thiol nucleophiles. The adducts formed by this reaction were successfully purified using one-step centrifugal partition chromatography (CPC) and identified by chromatographic and spectroscopic methods. The nine derivatives showed a concentration-dependent free radical scavenging activity in the DPPH assay. All compounds were also tested against a panel of pathogenic bacterial strains formed by Listeria monocytogenes (ATCC 7644 and 19115), Staphylococcus aureus (ATCC 9144), Escherichia coli (ATCC 11775 and 25922), and Salmonella enterica (ATCC 13076). In addition, adducts were tested against two no-pathogenic strains, Limosilactobacillus fermentum UCO-979C and Lacticaseibacillus rhamnosus UCO-25A. Overall, thiol-derived adducts displayed antimicrobial properties and, in some specific cases, inhibited biofilm formation, particularly in Listeria monocytogenes (ATCC 7644). Interestingly, phenolic adducts were inactive against all the strains and could not inhibit its biofilm formation. Moreover, depending on the structure, in specific cases, biofilm formation was strongly promoted. These findings contribute to demonstrating that CPC is a powerful tool to isolate new semi-synthetic molecules using avocado peels as starting material for PACc extraction. These compounds represent new lead molecules with antioxidant and antimicrobial activity.


Subject(s)
Antioxidants , Catechin , Persea , Proanthocyanidins , Persea/chemistry , Antioxidants/pharmacology , Antioxidants/chemistry , Antioxidants/chemical synthesis , Proanthocyanidins/chemistry , Proanthocyanidins/pharmacology , Proanthocyanidins/chemical synthesis , Proanthocyanidins/isolation & purification , Catechin/chemistry , Catechin/pharmacology , Plant Extracts/chemistry , Plant Extracts/pharmacology , Microbial Sensitivity Tests , Anti-Infective Agents/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/chemical synthesis , Sulfhydryl Compounds/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/isolation & purification , Phenols/chemistry , Phenols/pharmacology , Phenols/isolation & purification , Phenols/chemical synthesis
7.
Physiol Rep ; 12(8): e16020, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38658362

ABSTRACT

Desminopathy R350P is a human myopathy that is characterized by the progressive loss of muscle fiber organization. This results in the loss of muscle size, mobility, and strength. In desminopathy, inflammation affects muscle homeostasis and repair, and contributes to progressive muscle deterioration. Mitochondria morphology was also suggested to affect desminopathy progression. Epicatechin (Epi)-a natural compound found in cacao-has been proposed to regulate inflammatory signaling and mitochondria morphology in human and animal models. Hence, we hypothesize chronic Epi consumption to improve inflammatory pathway and mitochondria morphology in the peripheral blood mononuclear cells (PBMCs) of a desminopathy R350P patient. We found that 12 weeks of Epi consumption partially restored TRL4 signaling, indicative of inflammatory signaling and mitochondria morphology in the desminopathy patient. Moreover, Epi consumption improved blood health parameters, including reduced HOMA-IR and IL-6 levels in the desminopathy patient. This indicates that Epi consumption could be a useful tool to slow disease progression in desminopathy patients.


Subject(s)
Catechin , Leukocytes, Mononuclear , Mitochondria , Humans , Catechin/pharmacology , Catechin/administration & dosage , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/drug effects , Mitochondria/metabolism , Mitochondria/drug effects , Mitochondria/pathology , Male , Muscular Dystrophies/metabolism , Muscular Dystrophies/pathology , Muscular Dystrophies/drug therapy , Muscular Dystrophies/genetics , Adult , Female , Inflammation/metabolism , Inflammation/pathology , Cardiomyopathies/metabolism , Cardiomyopathies/pathology , Cardiomyopathies/drug therapy , Desmin/metabolism , Desmin/genetics
8.
Braz Dent J ; 35: e245509, 2024.
Article in English | MEDLINE | ID: mdl-38537010

ABSTRACT

High expression of MMP-2 and MMP-9 in periapical lesions plays an important role in the degradation of the extracellular matrix. This study aimed to investigate the effect of epigallocatechin-3-gallate (EGCG)-based endodontic paste as an intracanal dressing on the expression of MMP-2 and MMP-9 in periapical lesions. Periapical lesions were experimentally induced in 35 mature beagle dog premolars randomly divided into healthy teeth, untreated periapical lesions, periapical lesions treated in a single session (control groups), and periapical lesions treated in two sessions with EGCG or calcium hydroxide-based pastes (experimental groups). After 120 days, specimens were obtained for histopathologic and immunofluorescence analyses to assess the expression of MMP-2 and MMP-9. The statistical analysis was performed using a p-value of 0.05. Endodontic treatment in two sessions using medication with EGCG and calcium hydroxide-based pastes provided similar repair of the apical and periapical tissues and neoformation of periodontal ligament fibers, cementum, and alveolar bone (p>0.05). The experimental groups treated in two sessions with both medications presented expression of MMP-2 and MMP-9 similar to that in healthy teeth (p>0.05), and significantly lower than teeth treated in a single session or untreated periapical lesions (p <0.001). Expression of MMP-2 and MMP-9 was observed in the cytoplasm of fibroblasts, osteoblasts, cementoblasts, cementocytes, and vascular endothelium. The use of EGCG-based endodontic paste reduced the expression of MMP-2 and MMP-9 and allowed repair of periapical lesions, similar to calcium hydroxide-based paste, and superior to treatment performed in a single session.


Subject(s)
Catechin/analogs & derivatives , Periapical Periodontitis , Dogs , Animals , Matrix Metalloproteinase 9 , Calcium Hydroxide/pharmacology , Matrix Metalloproteinase 2 , Bandages
9.
J Ethnopharmacol ; 324: 117806, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38278373

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Monteverdia ilicifolia (Maytenus ilicifolia, Celastraceae), known as "espinheira-santa", has been widely used in Brazil to manage mainly gastrointestinal diseases. This species has been listed in the Brazilian Pharmacopeia and in the National List of Essential Medicines (RENAME). Considering that clinical studies about M. ilicifolia are rare, our group has been performing a broader project designed to evaluate the efficacy of M. ilicifolia capsules in a clinical trial, for this reason, approaches to provide safety to those patients are relevant. AIM OF THE STUDY: We aimed to investigate the potential pharmacokinetic interaction and hepatotoxicity and intestinal toxicity of an aqueous extract of M. ilicifolia and its main phytocompounds, catequin, epicatequin, and quercetin. METHODS AND MATERIALS: Slices of liver and intestine of Wistar rats were incubated with different concentrations of M. ilicifolia extract or isolated compounds (catechin, epicatechin and quercetin). Commercial kits were used to evaluate enzyme activities of CYP2D6 and CYP3A4 isoforms, as well as cell viability (MTT) assay and intracellular enzymes leakage, specifically lactate dehydrogenase (LDH), alkaline phosphatase (AP), aspartate aminotransferase (AST), alanine aminotransferase (ALT) were studied. RESULTS: Incubation with M. ilicifolia extract, catechin, epicatechin and quercetin did not affect significantly any evaluated parameter in intestines. The intracellular enzymes leakages, CYP2D6, LDH and AST, were increased with M. ilicifolia extract and quercetin in liver slices. CONCLUSIONS: Our in vitro findings highlighted, for the first time, the potential hepatotoxicity induced by an aqueous extract of M. ilicifolia, consequently this species and its products should be avoided in liver diseases, supporting that studies of safety must be performed including in the context of traditional medicinal plants.


Subject(s)
Catechin , Celastraceae , Chemical and Drug Induced Liver Injury , Maytenus , Plants, Medicinal , Humans , Rats , Animals , Brazil , Plant Extracts/toxicity , Quercetin , Cytochrome P-450 CYP2D6 , Rats, Wistar
10.
Food Funct ; 15(2): 930-952, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38170559

ABSTRACT

The nutritional quality of third-generation snacks prepared from rice flour by extrusion can be improved by the addition of polyphenols such as catechins, which are known to be more stable at high temperatures. However, the extrusion parameters can impact the breakdown and release of bioactive compounds and decrease the catechin bioaccessibility. Accordingly, this study investigated the impact of different extrusion parameters, including different extrusion temperatures (110, 135, and 150 °C) and moisture content prior to extrusion (27 and 31%), on the breakdown and bioaccessibility of catechin-enriched snacks during in vitro dynamic digestion using the Human Gastric Simulator (HGS). The extrusion parameters did not significantly impact most measured variables by themselves, indicating that within the tested ranges, any of the processing conditions could be used to produce a product with similar digestive behavior. However, the interaction of extrusion parameters (temperature and moisture content) played a significant role in the snack behavior during digestion. For example, the combination of 27% moisture content and 150 °C extrusion temperature had higher catechin bioaccessibility and higher starch hydrolysis than the other treatments. Overall, these findings suggest that the processing conditions of third generation snacks enriched with catechin can be optimized within certain ranges with limited modifications in the digestive properties.


Subject(s)
Catechin , Snacks , Humans , Temperature , Starch/metabolism
11.
J Ethnopharmacol ; 323: 117716, 2024 Apr 06.
Article in English | MEDLINE | ID: mdl-38190955

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Mimosa caesalpiniifolia (Sansão-do-Campo) is a native species of the caatinga in northeastern Brazil that has been studied for its potential anti-inflammatory and antidepressant activity. It is popularly consumed as a medicinal plant and its pharmacological benefits are evidenced in the literature. AIM OF THE STUDY: The present work was carried out to promote the chemical profile and evaluate the pharmacological activity of the dry extract and the ethyl acetate fraction obtained from the dry leaves of Mimosa caesalpiniifolia. MATERIALS AND METHODS: The leaves were collected in the municipality of Alfenas-MG and subjected to drying, followed by division in a knife mill. The preparation of the dry extract was carried out by the extraction method using simple percolation and the fraction was obtained by liquid-liquid partition. Part of the extractive solution was concentrated in a rotary evaporator followed by a drying process using the spray technique with the addition of colloidal silicon dioxide. The dry extract (33.33%) showed a higher yield in mass when compared to the yield of the ethyl acetate fraction (19.67%). The in vivo pharmacological evaluation was conducted with a total of 82 male Wistar rats that underwent cecal ligation and perforation surgery to induce the inflammatory process. One week after surgery, these animals were treated for 7 days with the dry extract and the ethyl acetate fraction and submitted to behavioral tests (open field and forced swimming). RESULTS: The chemical results were obtained through analysis by HPLC-PDA coupled to a mass spectrometer, enabling the verification of the presence of phenolic acids, flavonoids, aglycones, and glycosides, in addition to tannins. This corroborates with data present in the literature for the genus Mimosa sp. Some compounds had their structure determined, where they were identified as catechin (m/z 288.97), cassiaocidentalin A (m/z 560.75), and procyanidin B2 [(epi)catechin-(epi)catechin; m/z 576.83)]. It was found that the animals that were submitted to the treatment did not present statistically significant results, demonstrating that the pharmacological action evaluated in the test was not highlighted in this type of experiment. The groups that underwent treatment had an aggravated locomotor activity. CONCLUSIONS: The results found with the chemical study contributed to the knowledge of the plant species studied. On the other hand, further studies are needed to provide a better understanding of the pharmacological evaluation of Mimosa caesalpiniifolia.


Subject(s)
Acetates , Catechin , Mimosa , Rats , Animals , Rats, Wistar , Mimosa/chemistry , Plant Extracts/pharmacology , Plant Extracts/analysis , Plant Leaves/chemistry
12.
Nutrients ; 16(2)2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38276564

ABSTRACT

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


Subject(s)
Catechin , Animals , Humans , Catechin/pharmacology , Catechin/therapeutic use , Catechin/metabolism , Muscle Fibers, Skeletal , Muscle, Skeletal/metabolism , Muscular Atrophy/drug therapy , Muscular Atrophy/metabolism , MyoD Protein/metabolism , TOR Serine-Threonine Kinases/metabolism
13.
Molecules ; 28(21)2023 Oct 25.
Article in English | MEDLINE | ID: mdl-37959682

ABSTRACT

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 ß-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.


Subject(s)
Catechin , Polyphenols , Polyphenols/pharmacology , Tea , Amyloid/chemistry , Amyloidogenic Proteins , Catechin/pharmacology , Catechin/chemistry
14.
Food Res Int ; 173(Pt 1): 113266, 2023 11.
Article in English | MEDLINE | ID: mdl-37803579

ABSTRACT

In this study, different Deep Eutectic Solvents based on choline chloride ([Ch]Cl) with carboxylic acids, sugars, and glycerol, were investigated as alternative solvents for the extraction of flavonoids from soybean and okara. Initially, the COSMO-SAC was investigated as a tool in solvent screening for the extraction of flavonoids. Experimental validation was performed using total flavonoid analysis with the solvents that showed greater interaction with the solutes. The extracts obtained from soybean and okara using the DES [Ch]Cl:acetic acid added with 30 % water showed the highest total flavonoid content, 1.05 mg eq. of catechin/g dry soybean and 0.94 mg eq. of catechin /g dry okara, respectively. For phenolic compound extraction, [Ch]Cl: acetic acid DES extracted approximately 1.16 mg GAE/g of soybean and 0.69 mg GAE/g of okara. For antioxidant activity, soybean and okara extracts obtained with [Ch]Cl: acetic acid showed FRAP results of 0.40 mg Trolox/mL of extract and 0.45 mg Trolox/mL of extract, respectively. In addition, the isoflavones daidzein, genistein, glycitein, daidzin, genistin, and glycitin were identified and quantified in the soybean and okara extracts obtained with DES [Ch]Cl: acetic acid with 30% water, totaling 1068.05 and 424.32 µg total isoflavones/g dry sample. Therefore, The COSMO-SAC model was a useful tool in solvent screening, saving time and costs. Also, DES can be an alternative solvent for extracting flavonoids to replace conventional organic solvents, respecting current environmental and human health concerns.


Subject(s)
Catechin , Isoflavones , Humans , Flavonoids/analysis , Glycine max , Deep Eutectic Solvents , Plant Extracts/analysis , Isoflavones/analysis , Solvents/analysis , Water , Acetates
15.
Food Res Int ; 173(Pt 2): 113343, 2023 11.
Article in English | MEDLINE | ID: mdl-37803697

ABSTRACT

The fruits of the native tree Cryptocarya alba Mol. (Lauraceae), known as "peumo" were consumed by the Mapuche Amerindians in Chile both raw and after boiling. The aim of this work was to compare the content of phenolic, procyanidins, antioxidant capacity and inhibition of enzymes related with metabolic syndrome (α-glucosidase, α-amylase and pancreatic lipase) from the phenolic enriched extracts (PEEs) of peumo fruits. Fruits were collected during two years in three different places in central Chile and were investigated raw, boiled, and after separation into cotyledons and peel. The water resulting from the fruit decoction was also analyzed. The composition of the PEE was assessed by HPLC-DAD-MS/MS and the main compounds were quantified by HPLC. The strong inhibitory effect on α-glucosidase, with IC50 values below 1 µg/mL for several samples, was related, at least in part, to the content of 3-caffeoylquinic acid, 5-caffeoylquinic acid and (-)-epicatechin. The effect of the PEE on pancreatic lipase is of interest and can be partially explained by the (-)-epicatechin content. PCA analyses showed a clear separation of the samples according to the fruit parts and processing. However, no differences by geographic origin were observed. The activity of peumo PEEs on enzymes related to metabolic syndrome and its antioxidant capacity support further studies on the health promoting properties of this native Chilean food plant.


Subject(s)
Catechin , Cryptocarya , Metabolic Syndrome , Antioxidants/pharmacology , Cryptocarya/metabolism , Fruit/chemistry , Tandem Mass Spectrometry , alpha-Glucosidases/metabolism , Phenols/analysis , Lipase
16.
Molecules ; 28(17)2023 Aug 24.
Article in English | MEDLINE | ID: mdl-37687058

ABSTRACT

Breast cancer, due to its high incidence and mortality, is a public health problem worldwide. Current chemotherapy uses non-specific cytotoxic drugs, which inhibit tumor growth but cause significant adverse effects. (-)-Epicatechin (EC) is part of a large family of biomolecules called flavonoids. It is widely distributed in the plant kingdom; it can be found in green tea, grapes, and cocoa. Several studies in animals and humans have shown that EC induces beneficial effects in the skeletal muscle and the cardiovascular system, reducing risk factors such as arterial hypertension, endothelial dysfunction, damage to skeletal muscle structure, and mitochondrial malfunction by promoting mitochondrial biogenesis, with no adverse effects reported. Recently, we reported that EC had an antitumor effect in a murine triple-negative mammary gland tumor model, decreasing tumoral size and volume and increasing survival by 44%. This work aimed to characterize the effects of flavanol EC on proliferation, migration, and metastasis markers of triple-negative murine breast (4T1) cancer cells in culture. We found proliferation diminished and Bax/Bcl2 ratio increased. When the migration of culture cells was evaluated, we observed a significant reduction in migration. Also, the relative expression of the genes associated with metastasis, Cdh1, Mtss1, Pten, Bmrs, Fat1, and Smad4, was increased. In conclusion, these results contribute to understanding molecular mechanisms activated by EC that can inhibit metastatic-associated proliferation, migration, and invasion of murine breast cancer cells.


Subject(s)
Catechin , Drug-Related Side Effects and Adverse Reactions , Humans , Animals , Mice , Catechin/pharmacology , Neoplastic Processes , Flavonoids/pharmacology , Cell Proliferation
17.
Phys Chem Chem Phys ; 25(28): 19182-19194, 2023 Jul 19.
Article in English | MEDLINE | ID: mdl-37431676

ABSTRACT

The misfolding and aggregation of the presynaptic protein α-synuclein (α-syn) is a pathological hallmark of Parkinson's disease (PD). Targeting α-syn has emerged as a promising therapeutic strategy for PD. Emerging in vitro evidence supports a dual action of epigallocatechin-3-gallate (EGCG) against amyloid neurotoxicity. EGCG can halt the formation of toxic aggregates by redirecting the amyloid fibril aggregation pathway toward non-toxic aggregates and remodeling the existing toxic fibrils into non-toxic aggregates. Moreover, EGCG oxidation can enhance fibril's remodeling by forming Schiff bases, leading to crosslinking of the fibril. However, this covalent modification is not required for amyloid remodeling, and establishing non-specific hydrophobic interactions with sidechains seems to be the main driver of amyloid remodeling by EGCG. Thioflavin (ThT) is a gold standard probe to detect amyloid fibrils in vitro, and oxidized EGCG competes with ThT for amyloid fibrils' binding sites. In this work, we performed docking and molecular dynamics (MD) simulations to gain insights into the intermolecular interactions of oxidized EGCG and ThT with a mature α-syn fibril. We find that oxidized EGCG moves within lysine-rich sites within the hydrophobic core of the α-syn fibril, forming aromatic and hydrogen-bonding (H-bond) interactions with different residues during the whole MD simulation time. In contrast, ThT, which does not remodel amyloid fibrils, was docked to the same sites but only via aromatic interactions. Our findings suggest that non-covalent interactions play a role in oxidized EGCG binding into the hydrophobic core, including H-bond and aromatic interactions with some residues in the amyloid remodeling processes. These interactions would ultimately lead to a disturbance of structural features as determinants for stabilizing this fibril into a compact and pathogenic Greek key topology.


Subject(s)
Catechin , Parkinson Disease , Humans , alpha-Synuclein/chemistry , Amyloid/chemistry , Parkinson Disease/metabolism , Amyloidogenic Proteins , Catechin/chemistry , Protein Aggregates
18.
Int J Mol Sci ; 24(13)2023 Jun 27.
Article in English | MEDLINE | ID: mdl-37445915

ABSTRACT

Breast cancer is one of the most diagnosed cancers worldwide, with an incidence of 47.8%. Its treatment includes surgery, radiotherapy, chemotherapy, and antibodies giving a mortality of 13.6%. Breast tumor development is driven by a variety of signaling pathways with high heterogeneity of surface receptors, which makes treatment difficult. Epigallocatechin-3-gallate (EGCG) is a natural polyphenol isolated as the main component in green tea; it has shown multiple beneficial effects in breast cancer, controlling proliferation, invasion, apoptosis, inflammation, and demethylation of DNA. These properties were proved in vitro and in vivo together with synergistic effects in combination with traditional chemotherapy, increasing the effectiveness of the treatment. This review focuses on the effects of EGCG on the functional capabilities acquired by breast tumor cells during its multistep development, the molecular and signal pathways involved, the synergistic effects in combination with current drugs, and how nanomaterials can improve its bioavailability on breast cancer treatment.


Subject(s)
Breast Neoplasms , Catechin , Humans , Female , Breast Neoplasms/metabolism , Catechin/pharmacology , Catechin/therapeutic use , Polyphenols/pharmacology , Breast/metabolism , Signal Transduction , Apoptosis , Tea
19.
Food Res Int ; 170: 112979, 2023 08.
Article in English | MEDLINE | ID: mdl-37316016

ABSTRACT

This article studies the release of phenolic compounds during cocoa heating under vacuum, N2, and air atmospheres, and proposes fast heating (60 °C • s-1) as a methodology that allows the release of polyphenols from fermented cocoa powder. We aim to demonstrate that gas phase transport is not the only mechanism to extract compounds of interest and that convective-type mechanisms can facilitate the process by reducing their degradation. The oxidation and transport phenomena were evaluated both in the extracted fluid and in the solid sample during the heating process. Polyphenols transport phenomena were assessed based on the fluid (chemical condensate compounds) that was collected cold with an organic solvent (methanol) in a hot plate reactor. Out of all the polyphenolic compounds present in cocoa powder, we assessed specifically the release of catechin and epicatechin. We found that high heating rates combined with vacuum or N2 favor the ejection of liquids; then, it is possible to extract compounds such as catechin-which is dissolved/entrained and transported in the ejected liquids-and avoid degradation phenomena.


Subject(s)
Catechin , Chocolate , Heating , Phenols , Polyphenols
20.
J Toxicol Environ Health A ; 86(16): 557-574, 2023 08 18.
Article in English | MEDLINE | ID: mdl-37350297

ABSTRACT

This study aimed to characterize the phytochemical profile of bark and leaves aqueous extract Commiphora leptophloeos, and conduct in vivo and in vitro assays to determine the presence of any toxicological consequences due to exposure. The phytochemical analysis was carried out using high-performance liquid chromatography (HPLC). The antioxidant activity was estimated utilizing DPPH free radical scavenging and phosphomolybdenum assays. Cell viability was measured by the MTT method on J774 and human adenocarcinoma cells, which were treated with concentrations of 12,5, 25, 50, 100 or 200 µg/ml of both extracts. Acute oral toxicity, genotoxicity, and mutagenicity assays were determined using a single oral dose of 2000 g/kg in male Swiss albino mice (Mus musculus). Biochemical analysis of the blood and histological analyses of the kidneys, liver, spleen, pylorus, duodenum and jejunum were undertaken. Genotoxicity and mutagenicity were determined utilizing blood samples. Gallic acid, catechin, and epicatechin were identified in the bark and chlorogenic acid in leaves. Data demonstrated a high content of phenolic compounds and flavonoids associated with significant antioxidant potential. No significant signs in damage or symptoms of toxicity were detected. No marked reduction in cell viability was found at lower concentrations tested. On histomorphometry, only the gastrointestinal organs exhibited significant difference. Renal hepatic and blood parameters were within the normal range. No apparent signs of toxicity, genotoxicity, mutagenicity or cytotoxicity were found in vivo and in vitro experiments.


Subject(s)
Antioxidants , Catechin , Mice , Animals , Male , Humans , Antioxidants/chemistry , Plant Extracts/toxicity , Plant Extracts/chemistry , Commiphora , Plant Bark/chemistry , Phytochemicals/toxicity , Plant Leaves/chemistry
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