Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 82
Filter
Add more filters










Publication year range
1.
Colloids Surf B Biointerfaces ; 225: 113244, 2023 May.
Article in English | MEDLINE | ID: mdl-36905836

ABSTRACT

Oxidative stress caused by environmental exposures results in numerous skin diseases. Phloretin (PHL) is often used to relieve various skin symptoms, however, precipitation or crystallization of PHL in aqueous systems limits its ability to diffuse through the stratum corneum, making it difficult to exert effect at the target. To address this challenge, we herein report a method for the generation of core-shell nanostructure (G-LSS) via the growth of sericin crust around gliadin nanoparticle as a topical nanocarrier of PHL to improve its cutaneous bioavailability. Physicochemical performance, morphology, stability, and antioxidant activity of the nanoparticles were characterized. G-LSS-PHL exhibited uniformed spherical nanostructures with the robust encapsulation on PHL (∼90 %). This strategy protected PHL from UV-induced degradation, facilitating to inhibit erythrocyte hemolysis and quench free radicals in a dose-dependent manner. Transdermal delivery experiments and porcine skin fluorescence imaging indicated that G-LSS facilitated the penetration of PHL across the epidermis layer of skin to reach deep-seated sites, and promoted cumulative turnover of PHL with a 2.0-fold increase. Cell cytotoxicity and uptake assay confirmed that as-prepared nanostructure was nontoxic to HSFs, and promoted cellular absorption of PHL. Therefore, this work opened up new promising avenues for developing robust antioxidant nanostructure for topical applications.


Subject(s)
Nanoparticles , Sericins , Animals , Swine , Antioxidants/pharmacology , Antioxidants/metabolism , Sericins/pharmacology , Gliadin , Phloretin/pharmacology , Phloretin/chemistry , Skin , Administration, Cutaneous , Nanoparticles/chemistry
2.
Biotechnol J ; 18(6): e2200609, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36974342

ABSTRACT

C-glycosyltransferases (C-GTs) offer selective and efficient synthesis of natural product C-glycosides under mild reaction conditions. In contrast, the chemical synthesis of these C-glycosides is challenging and environmentally harmful. The rare occurrence of C-glycosylated compounds in Nature, despite their stability, suggests that their biosynthetic enzymes, C-GTs, might be scarce. Indeed, the number of characterized C-GTs is remarkably lower than O-GTs. Therefore, discovery efforts are crucial for expanding our knowledge of these enzymes and their efficient application in biocatalytic processes. This study aimed to identify new C-GTs based on their primary sequence. 18 new C-GTs were discovered, 10 of which yielded full conversion of phloretin to its glucosides. Phloretin is a dihydrochalcone natural product, with its mono-C-glucoside, nothofagin, having various health-promoting effects. Several of these enzymes enabled highly selective production of either nothofagin (UGT708A60 and UGT708F2) or phloretin-di-C-glycoside (UGT708D9 and UGT708B8). Molecular docking simulations, based on structural models of selected enzymes, showed productive binding modes for the best phloretin C-GTs, UGT708F2 and UGT708A60. Moreover, we characterized UGT708A60 as a highly efficient phloretin mono-C glycosyltransferase (kcat  = 2.97 s-1 , KM  = 0.1 µM) active in non-buffered, dilute sodium hydroxide (0.1-1 mM). We further investigated UGT708A60 as an efficient biocatalyst for the bioproduction of nothofagin.


Subject(s)
Glycosyltransferases , Phloretin , Glycosyltransferases/chemistry , Phloretin/chemistry , Phloretin/metabolism , Molecular Docking Simulation , Glycosides
3.
Molecules ; 27(24)2022 Dec 12.
Article in English | MEDLINE | ID: mdl-36557950

ABSTRACT

Phloretin is a natural dihydrochalcone found in many fruits and vegetables, especially in apple tree leaves and the Manchurian apricots, exhibiting several therapeutic properties, such as antioxidant, antidiabetic, anti-inflammatory, and antitumor activities. In this review article, the diverse aspects of the anticancer potential of phloretin are addressed, presenting its antiproliferative, proapoptotic, antimetastatic, and antiangiogenic activities in many different preclinical cancer models. The fact that phloretin is a planar lipophilic polyphenol and, thus, a membrane-disrupting Pan-Assay Interference compound (PAIN) compromises the validity of the cell-based anticancer activities. Phloretin significantly reduces membrane dipole potential and, therefore, is expected to be able to activate a number of cellular signaling pathways in a non-specific way. In this way, the effects of this minor flavonoid on Bax and Bcl-2 proteins, caspases and MMPs, cytokines, and inflammatory enzymes are all analyzed in the current review. Moreover, besides the anticancer activities exerted by phloretin alone, its co-effects with conventional anticancer drugs are also under discussion. Therefore, this review presents a thorough overview of the preclinical anticancer potential of phloretin, allowing one to take the next steps in the development of novel drug candidates and move on to clinical trials.


Subject(s)
Neoplasms , Phloretin , Humans , Phloretin/pharmacology , Phloretin/chemistry , Neoplasms/drug therapy , Cytokines , Flavonoids/therapeutic use , Caspases
4.
Nutrients ; 14(17)2022 Sep 02.
Article in English | MEDLINE | ID: mdl-36079895

ABSTRACT

Phloretin is a flavonoid of the dihydrogen chalcone class, present abundantly in apples and strawberries. The beneficial effects of phloretin are mainly associated with its potent antioxidant properties. Phloretin modulates several signaling pathways and molecular mechanisms to exhibit therapeutic benefits against various diseases including cancers, diabetes, liver injury, kidney injury, encephalomyelitis, ulcerative colitis, asthma, arthritis, and cognitive impairment. It ameliorates the complications associated with diabetes such as cardiomyopathy, hypertension, depression, memory impairment, delayed wound healing, and peripheral neuropathy. It is effective against various microbial infections including Salmonella typhimurium, Listeria monocytogenes, Mycobacterium tuberculosis, Escherichia coli, Candida albicans and methicillin-resistant Staphylococcus aureus. Considering the therapeutic benefits, it generated interest for the pharmaceutical development. However, poor oral bioavailability is the major drawback. Therefore, efforts have been undertaken to enhance its bioavailability by modifying physicochemical properties and molecular structure, and developing nanoformulations. In the present review, we discussed the pharmacological actions, underlying mechanisms and molecular targets of phloretin. Moreover, the review provides insights into physicochemical and pharmacokinetic characteristics, and approaches to promote the pharmaceutical development of phloretin for its therapeutic applications in the future. Although convincing experimental data are reported, human studies are not available. In order to ascertain its safety, further preclinical studies are needed to encourage its pharmaceutical and clinical development.


Subject(s)
Diabetes Mellitus , Methicillin-Resistant Staphylococcus aureus , Diabetes Mellitus/drug therapy , Drug Development , Flavonoids , Humans , Methicillin-Resistant Staphylococcus aureus/metabolism , Phloretin/chemistry , Phloretin/pharmacology , Phloretin/therapeutic use
5.
Toxicol Appl Pharmacol ; 434: 115822, 2022 01 01.
Article in English | MEDLINE | ID: mdl-34896434

ABSTRACT

Our recent investigation directed to synthesize a novel ruthenium-phloretin complex accompanied by the study of antioxidant in addition to DNA binding capabilities, to determine the chemotherapeutic activity against breast carcinoma in vitro and in vivo. Ruthenium-phloretin complex was synthesized and characterized by different spectroscopic methods. The complex was further investigated to determine its efficacy in both MCF-7 and MDA-MB-231 human carcinoma cell lines and finally in an in vivo model of mammary carcinogenesis induced by DMBA in rats. Our studies confirm that the chelation of the metal and ligand was materialize by the 3-OH and 9-OH functional groups of the ligand and the complex is found crystalline and was capable of intercalating with CT-DNA. The complex was capable of reducing cellular propagation and initiate apoptotic events in MCF-7 and MDA-MB-231 breast carcinoma cell lines. Ruthenium-phloretin complex could modulate p53 intervene apoptosis in the breast carcinoma, initiated by the trail of intrinsic apoptosis facilitated through Bcl2 and Bax and at the same time down regulating the PI3K/Akt/mTOR pathway coupled with MMP9 regulated tumor invasive pathways. Ruthenium-phloretin chemotherapy could interrupt, revoke or suspend the succession of breast carcinoma by altering intrinsic apoptosis along with the anti-angiogenic pathway.


Subject(s)
Breast Neoplasms/drug therapy , Malus/chemistry , Phloretin/pharmacology , Phosphatidylinositol 3-Kinases/metabolism , Ruthenium Compounds/pharmacology , Tumor Microenvironment/drug effects , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , Mammary Neoplasms, Animal/chemically induced , Mammary Neoplasms, Animal/drug therapy , Mice , Neoplasms, Experimental , Phloretin/chemistry , Phosphatidylinositol 3-Kinases/genetics , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Rats , Rats, Sprague-Dawley , Ruthenium Compounds/chemistry , Ruthenium Compounds/toxicity , TOR Serine-Threonine Kinases , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism
6.
Bioengineered ; 12(1): 2420-2431, 2021 12.
Article in English | MEDLINE | ID: mdl-34167447

ABSTRACT

Oral candidiasis is one of the most common types of fungal infection caused by Candida albicans (C. albicans). The present study aims to investigate the antifungal effects of phloretin (a dihydrochalcone flavonoid) against the C. albicans pathogenicity. In this work, we treated C. albicans SC5314 with 37.28, 74.55, or 149.10 µg/mL (equivalent to 0.5×, 1× or 2× MIC) phloretin in vitro. Besides, we established a mice model of oral candidiasis by a sublingual infection of C. albicans suspension (1 × 107 colony-forming unit/mL), and mice were treated with phloretin (3.73 or 7.46 mg/mL, which were equivalent to 50× or 100× MIC) twice a day starting on day one post-infection. The results showed that the MIC of phloretin against C. albicans was 74.55 µg/mL. Phloretin exerted antifungal activity by inhibiting the biofilm formation and suppressing the yeast-to-hyphae transition upon the downregulation of hypha-associated genes including enhanced adherence to polystyrene 1, the extent of cell elongation gene 1, hyphal wall protein 1 gene, and agglutinin-like sequence gene 3. Next, phloretin repressed the secretion of proteases and phospholipases via reducing the expression of protease-encoding genes secreted aspartyl proteases (SAP)1 and SAP2, as well as phospholipase B1. Subsequently, the in vivo antifungal activity of phloretin was testified by the reverse of the enhanced lesion severity, inflammatory infiltration, and the increased colony-forming unit counts caused by C. albicans of tongue tissues in oral candidiasis mice. In conclusion, phloretin suppressed the pathogenicity and virulence factors against C. albicans both in vivo and in vitro.


Subject(s)
Candida albicans/pathogenicity , Phloretin/pharmacology , Virulence Factors/antagonists & inhibitors , Animals , Antifungal Agents/pharmacology , Biofilms/drug effects , Biofilms/growth & development , Candida albicans/drug effects , Candidiasis/drug therapy , Candidiasis/microbiology , Disease Models, Animal , Female , Hyphae/drug effects , Mice, Inbred BALB C , Microbial Sensitivity Tests , Mouth/microbiology , Mouth/pathology , Peptide Hydrolases/metabolism , Phloretin/chemistry , Phloretin/therapeutic use , Phospholipases/metabolism , Virulence Factors/metabolism
7.
Int J Mol Sci ; 22(6)2021 Mar 13.
Article in English | MEDLINE | ID: mdl-33805725

ABSTRACT

Monocarboxylate transporters (MCTs) are of great research interest for their role in cancer cell metabolism and their potential ability to transport pharmacologically relevant compounds across the membrane. Each member of the MCT family could potentially provide novel therapeutic approaches to various diseases. The major differences among MCTs are related to each of their specific metabolic roles, their relative substrate and inhibitor affinities, the regulation of their expression, their intracellular localization, and their tissue distribution. MCT4 is the main mediator for the efflux of L-lactate produced in the cell. Thus, MCT4 maintains the glycolytic phenotype of the cancer cell by supplying the molecular resources for tumor cell proliferation and promotes the acidification of the extracellular microenvironment from the co-transport of protons. A promising therapeutic strategy in anti-cancer drug design is the selective inhibition of MCT4 for the glycolytic suppression of solid tumors. A small number of studies indicate molecules for dual inhibition of MCT1 and MCT4; however, no selective inhibitor with high-affinity for MCT4 has been identified. In this study, we attempt to approach the structural characteristics of MCT4 through an in silico pipeline for molecular modelling and pharmacophore elucidation towards the identification of specific inhibitors as a novel anti-cancer strategy.


Subject(s)
Antineoplastic Agents/chemistry , Monocarboxylic Acid Transporters/chemistry , Muscle Proteins/chemistry , Phloretin/chemistry , Pyrimidinones/chemistry , Quercetin/chemistry , Reserpine/analogs & derivatives , Thiophenes/chemistry , Uracil/analogs & derivatives , Animals , Antineoplastic Agents/metabolism , Binding Sites , Biological Transport , Drug Design , Glycolysis/physiology , Humans , Lactic Acid/chemistry , Lactic Acid/metabolism , Molecular Docking Simulation , Monocarboxylic Acid Transporters/antagonists & inhibitors , Monocarboxylic Acid Transporters/genetics , Monocarboxylic Acid Transporters/metabolism , Muscle Proteins/antagonists & inhibitors , Muscle Proteins/genetics , Muscle Proteins/metabolism , Phloretin/metabolism , Phylogeny , Protein Binding , Protein Conformation, alpha-Helical , Protein Interaction Domains and Motifs , Protein Isoforms/antagonists & inhibitors , Protein Isoforms/chemistry , Protein Isoforms/genetics , Protein Isoforms/metabolism , Pyrimidinones/metabolism , Quercetin/metabolism , Reserpine/chemistry , Reserpine/metabolism , Structural Homology, Protein , Substrate Specificity , Thiophenes/metabolism , Uracil/chemistry , Uracil/metabolism
8.
J Med Chem ; 64(8): 4450-4461, 2021 04 22.
Article in English | MEDLINE | ID: mdl-33819035

ABSTRACT

Overexpression of glucose transporters (GLUTs) in colorectal cancer cells is associated with 5-fluorouracil (1, 5-FU) resistance and poor clinical outcomes. We designed and synthesized a novel GLUT-targeting drug conjugate, triggered by glutathione in the tumor microenvironment, that releases 5-FU and GLUTs inhibitor (phlorizin (2) and phloretin (3)). Using an orthotopic colorectal cancer mice model, we showed that the conjugate exhibited better antitumor efficacy than 5-FU, with much lower exposure of 5-FU during treatment and without significant side effects. Our study establishes a GLUT-targeting theranostic incorporating a disulfide linker between the targeting module and cytotoxic payload as a potential antitumor therapy.


Subject(s)
Antineoplastic Agents/chemistry , Enzyme Inhibitors/chemistry , Glucose Transport Proteins, Facilitative/antagonists & inhibitors , Animals , Antineoplastic Agents/metabolism , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Cell Survival/drug effects , Colorectal Neoplasms/chemically induced , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/metabolism , Disease Models, Animal , Drug Stability , Enzyme Inhibitors/metabolism , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/therapeutic use , Fluorouracil/therapeutic use , Glucose Transport Proteins, Facilitative/metabolism , Half-Life , Humans , Mice , Mice, Inbred BALB C , Phloretin/chemistry , Phloretin/metabolism , Phloretin/therapeutic use , Phlorhizin/chemistry , Phlorhizin/metabolism , Phlorhizin/therapeutic use , Structure-Activity Relationship , Tissue Distribution
9.
Eur J Pharmacol ; 889: 173593, 2020 Dec 15.
Article in English | MEDLINE | ID: mdl-32971088

ABSTRACT

Botanical molecules are known to have the ability to counteract ultraviolet radiation-induced skin damage. The interest in the development of natural compound-based products for the prevention of solar ultraviolet radiation-induced skin photoaging, melasma, and photocarcinogenesis has been increasing. Recently, the flavonoid phloretin has attracted the attention of researchers in the dermatological field for application in cosmetics and therapeutics. In addition to its antioxidant activity, phloretin has been shown to have properties such as anti-aging and depigmenting effects. In this study, we review the dermatological treatments with phloretin for conditions such as melasma, photoaging, acne, and melanoma. Phloretin has been shown to inhibit elastase and matrix metalloproteinase-1 activity, to reduce cellular tyrosinase activity and melanin content, and induce apoptosis in B16 mouse melanoma 4A5 cells. An in vivo study showed that phloretin, applied topically to the dorsal skin of mice, suppressed the 12-O-tetradecanoylphorbol 13-acetate-induced expression of COX-2, a critical molecular target of many chemopreventive, as well as anti-inflammatory agents. Phloretin can penetrate the skin; nevertheless, its penetration profile in different skin layers has not yet been evaluated. Despite its health benefits, phloretin application has been limited because of its photoinstability and poor aqueous solubility, among other limitations. Therefore, we reviewed the recent advances in pharmaceutical applications such as the use of nanotechnology, in order to improve the cutaneous availability of phloretin. In this review, we also focus on the oral application, product development challenges, and recent progress and future research directions on phloretin.


Subject(s)
Dermatologic Agents/administration & dosage , Dermatologic Agents/metabolism , Phloretin/administration & dosage , Phloretin/metabolism , Skin/drug effects , Skin/metabolism , Administration, Cutaneous , Administration, Oral , Animals , Dermatologic Agents/chemistry , Drug Delivery Systems/trends , Humans , Nanotechnology/trends , Phloretin/chemistry , Skin/radiation effects , Ultraviolet Rays/adverse effects
10.
Eur Biophys J ; 49(6): 463-472, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32705322

ABSTRACT

The ability of drugs to diffuse through the lipid bilayer of cell membranes is important for their metabolism, distribution, and efficacy. In this study, the interaction between phloretin and human serum albumin (HSA) in an L-egg lecithin phosphatidylcholine (PC) liposome suspension was investigated by fluorescence and absorbance spectroscopy. The spectroscopic and fluorescence quenching experiments show that phloretin molecules penetrated into the lumen of the liposome. The partition coefficient of phloretin in the PC liposome suspensions was calculated from fluorescence quenching measurements. The results show that phloretin efficiently quenches the intrinsic fluorescence of HSA through a combination of dynamic and static quenching. The values of Gibbs free energy, and the enthalpy and entropic change in the binding process of phloretin with HSA in the PC liposome suspensions were negative, suggesting that the binding process of phloretin and HSA was spontaneous. Hydrogen bonding and van der Waals force interactions play an important role in the interaction between the two molecules. In addition, binding of phloretin to HSA in liposome suspensions was investigated by synchronous fluorescence spectroscopy.


Subject(s)
Liposomes/chemistry , Phloretin/chemistry , Serum Albumin, Human/chemistry , Spectrum Analysis , Thermodynamics
11.
Oxid Med Cell Longev ; 2020: 7690845, 2020.
Article in English | MEDLINE | ID: mdl-32566099

ABSTRACT

To explore fresh strategies in colorectal cancer (CRC) chemotherapy, we evaluated the capability of the ruthenium-phloretin complex in exterminating colon cancer by effectively addressing multiple apoptotic mechanisms on HT-29 cancer cells together with an animal model of colorectal cancer activated by 1,2-dimethylhydrazine and dextran sulfate sodium. Our current approach offers tangible evidence of the application of the ruthenium-phloretin complex in future chemotherapy. The complex triggers intrinsic apoptosis triggered by p53 and modulates the Akt/mTOR pathway along with other inflammatory biomarkers. The ruthenium-phloretin complex has been synthesized and successfully characterized by numerous spectroscopic methodologies accompanied by DPPH, FRAP, and ABTS assays assessing its antioxidant potential. Studies conducted in human cell lines revealed that the complex improved levels of p53 and caspase-3 while diminishing the activities of VEGF and mTOR, triggers apoptosis, and induces fragmentation of DNA in the HT-29 cells. Toxicity studies were conducted to identify the therapeutic doses of the novel complex in animal models. The outcomes of the in vivo report suggest that the complex was beneficial in repressing multiplicity of aberrant crypt foci as well as hyperplastic lesions and also promoted increased levels of CAT, SOD, and glutathione. In addition, the ruthenium-phloretin complex was able to control cell proliferation and boosted apoptotic outbursts in cancer cells associated with the increase in cellular response towards Bax while diminishing responses towards Bcl-2, NF-κB, and MMP-9. Our observations from the experiments deliver testament that the ruthenium-phloretin complex has the potential to act as a promising chemotherapeutic agent in colorectal cancer because it can affect the growth of ACF and hyperplastic abrasions in the colon tissues by evoking cell death.


Subject(s)
Apoptosis , Colonic Neoplasms/drug therapy , Colonic Neoplasms/pathology , Phloretin/therapeutic use , Ruthenium/therapeutic use , Aberrant Crypt Foci/pathology , Animals , Antioxidants/pharmacology , Apoptosis/drug effects , Benzothiazoles/chemistry , Biphenyl Compounds/chemistry , Cell Proliferation/drug effects , Cell Survival/drug effects , Colon/drug effects , Colon/pathology , Colonic Neoplasms/blood , DNA/metabolism , Female , Free Radical Scavengers/pharmacology , HT29 Cells , Humans , Kidney/drug effects , Kidney/pathology , Male , Matrix Metalloproteinase 9/metabolism , Mice, Inbred BALB C , NF-kappa B/metabolism , Oxidation-Reduction , Phloretin/chemistry , Phloretin/pharmacology , Picrates/chemistry , Ruthenium/chemistry , Ruthenium/pharmacology , Spectroscopy, Fourier Transform Infrared , Sulfonic Acids/chemistry , Toxicity Tests , bcl-2-Associated X Protein/metabolism
12.
J Agric Food Chem ; 68(24): 6683-6691, 2020 Jun 17.
Article in English | MEDLINE | ID: mdl-32468814

ABSTRACT

In this study, we investigated an efficient enzymatic strategy for producing potentially valuable phloretin metabolites from phlorizin, a glucoside of phloretin that is rich in apple pomace. Almond ß-glucosidase efficiently removed phlorizin's glucose moiety to produce phloretin. CYP102A1 engineered by site-directed mutagenesis, domain swapping, and random mutagenesis catalyzed the highly regioselective C-hydroxylation of phloretin into 3-OH phloretin with high conversion yields. Under the optimal hydroxylation conditions of 15 g cells L-1 and a 20 mM substrate for whole-cell biocatalysis, phloretin was regioselectively hydroxylated into 3.1 mM 3-OH phloretin each hour. Furthermore, differentiation of 3T3-L1 preadipocytes into adipocytes and lipid accumulation were dramatically inhibited by 3-OH phloretin but promoted by phloretin. Consistent with these inhibitory effects, the expression of adipogenic regulator genes was downregulated by 3-OH phloretin. We propose a platform for the sustainable production and value creation of phloretin metabolites from apple pomace capable of inhibiting adipogenesis.


Subject(s)
Adipocytes/drug effects , Adipogenesis/drug effects , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Cytochrome P-450 Enzyme System/chemistry , Cytochrome P-450 Enzyme System/genetics , NADPH-Ferrihemoprotein Reductase/chemistry , NADPH-Ferrihemoprotein Reductase/genetics , Phlorhizin/chemistry , Plant Extracts/chemistry , Adipocytes/cytology , Animals , Bacterial Proteins/metabolism , Biocatalysis , Cytochrome P-450 Enzyme System/metabolism , Fruit/chemistry , Growth Inhibitors/chemistry , Growth Inhibitors/pharmacology , Malus/chemistry , Mice , NADPH-Ferrihemoprotein Reductase/metabolism , Phloretin/chemistry , Phlorhizin/pharmacology , Plant Extracts/pharmacology , Protein Engineering
13.
J Agric Food Chem ; 68(46): 13221-13230, 2020 Nov 18.
Article in English | MEDLINE | ID: mdl-32255614

ABSTRACT

In this study, we chemically modified a phytoglycogen structure to introduce negative surface charge via carboxymethylation (CMPG) and then prepared CMPG-based ternary nanocomplex particles through electrostatic interactions with sodium caseinate (core) and chemical cross-linking with pectin (shell). The chemical cross-linking process by glutaradehyde was systematically optimized under various temperatures and durations. The cross-linked ternary nanocomplex was comprehensively characterized, and our results showed that it had a size of 86 nm with a spherical shape, smooth surface, homogeneous distribution, and negative surface charge. The chemical cross-linking process significantly improved colloidal stability of the nanocomplex under simulated gastrointestinal fluids with digestive enzymes. The as-prepared nanocomplex exhibited exceptional capability to encapsulate phloretin, a natural dihydrochalcone, as a model lipophilic bioactive compound. The nanocomplex not only showed a slow and sustained kinetic release of phloretin under simulated gastrointestinal fluids but also dramatically enhanced its antioxidant activity under an aqueous environment compared to pure phloretin dissolved in ethanol. Findings from this work revealed the promising features of the as-prepared ternary nanocomplex as a potential oral delivery system for lipophilic bioactive compounds.


Subject(s)
Caseins/chemistry , Glycogen/chemistry , Nanostructures/chemistry , Pectins/chemistry , Phloretin/chemistry , Drug Carriers/chemistry , Drug Compounding/methods , Drug Delivery Systems , Static Electricity
14.
J Am Chem Soc ; 142(7): 3506-3512, 2020 02 19.
Article in English | MEDLINE | ID: mdl-31986016

ABSTRACT

A highly efficient di-C-glycosyltransferase GgCGT was discovered from the medicinal plant Glycyrrhiza glabra. GgCGT catalyzes a two-step di-C-glycosylation of flopropione-containing substrates with conversion rates of >98%. To elucidate the catalytic mechanisms of GgCGT, we solved its crystal structures in complex with UDP-Glc, UDP-Gal, UDP/phloretin, and UDP/nothofagin, respectively. Structural analysis revealed that the sugar donor selectivity was controlled by the hydrogen-bond interactions of sugar hydroxyl groups with D390 and other key residues. The di-C-glycosylation capability of GgCGT was attributed to a spacious substrate-binding tunnel, and the G389K mutation could switch di- to mono-C-glycosylation. GgCGT is the first di-C-glycosyltransferase with a crystal structure, and the first C-glycosyltransferase with a complex structure containing a sugar acceptor. This work could benefit the development of efficient biocatalysts to synthesize C-glycosides with medicinal potential.


Subject(s)
Glycosyltransferases/chemistry , Glycosyltransferases/metabolism , Glycyrrhiza/enzymology , Cloning, Molecular , Crystallography, X-Ray , Glycosylation , Glycosyltransferases/genetics , Glycyrrhiza/genetics , Ligands , Models, Molecular , Phloretin/chemistry , Phloretin/metabolism , Substrate Specificity , Transcriptome , Uridine Diphosphate Galactose/chemistry , Uridine Diphosphate Galactose/metabolism , Uridine Diphosphate Glucuronic Acid/chemistry , Uridine Diphosphate Glucuronic Acid/metabolism , Uridine Diphosphate N-Acetylglucosamine/chemistry , Uridine Diphosphate N-Acetylglucosamine/metabolism , Uridine Diphosphate Xylose/chemistry , Uridine Diphosphate Xylose/metabolism
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 226: 117642, 2020 Feb 05.
Article in English | MEDLINE | ID: mdl-31614273

ABSTRACT

Tyrosinase is the rate-limiting enzyme for controlling the production of melanin in the human body, and overproduction of melanin can lead to a variety of skin disorders. In this paper, the inhibitory kinetics of phloretin on tyrosinase and their binding mechanism were determined using spectroscopy, molecular docking, antioxidant assays and chromatography. The spectroscopic results indicate that phloretin reversibly inhibits tyrosinase in a mix-type manner through a multiphase kinetic process with the IC50 of 169.36 µmol/L. It is shown that phloretin has a strong ability to quench the intrinsic fluorescence of tyrosinase mainly through a static quenching procedure, suggesting that a stable phloretin-tyrosinase complex is generated. Molecular docking results suggest that the dominant conformation of phloretin binds to the gate of the active site of tyrosinase. Moreover, the antioxidant assays demonstrate that phloretin has powerful antioxidant capacity and has the ability to reduce o-dopaquinone to l-dopa just like ascorbic acid. Interestingly, the results of spectroscopy and chromatography indicate that phloretin is a substrate of tyrosinase but also an inhibitor. The possible inhibitory mechanism is proposed, which will be helpful to design and search for tyrosinase inhibitors.


Subject(s)
Enzyme Inhibitors , Monophenol Monooxygenase/antagonists & inhibitors , Monophenol Monooxygenase/metabolism , Phloretin/metabolism , Phloretin/pharmacology , Agaricus/enzymology , Antioxidants/chemistry , Antioxidants/metabolism , Antioxidants/pharmacology , Catalytic Domain/drug effects , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/metabolism , Enzyme Inhibitors/pharmacology , Kinetics , Melanins/metabolism , Molecular Docking Simulation , Monophenol Monooxygenase/chemistry , Phloretin/chemistry , Substrate Specificity
16.
Food Chem ; 308: 125569, 2020 Mar 05.
Article in English | MEDLINE | ID: mdl-31644967

ABSTRACT

In this study, the solubility of phloretin (PT) was enhanced via steviol glycoside (STE)-based micelle (MC) and solid dispersion (SD). Computer simulation, characterization, interaction with serum albumin (SA) and in vitro release were carried out to investigate the solubilization mechanisms and the difference in their solubilization capacities. For PT-loaded MC (STE-PT MC), PT was encapsulated into the hydrophobic core of a spherical micelle with a droplet diameter of 5 nm. For PT-loaded SD (STE-PT SD), PT was completely dispersed with the amorphous state in STE. Most of those PTs were directly dissolved in water, and few were encapsulated by STE micelles. The amorphous state combined with relatively large micelles contributed to the high solubilization capacity of STE-PT SD. In addition, PT of STE-PT SD exhibited a higher dissolution rate and more effective interaction with SA than that of STE-PT MC. No undesirable chemical interaction between PT and STE occurred.


Subject(s)
Diterpenes, Kaurane/chemistry , Glucosides/chemistry , Phloretin/chemistry , Hydrophobic and Hydrophilic Interactions , Micelles , Phloretin/analysis , Solubility , Water/chemistry
17.
Chem Biol Interact ; 308: 11-19, 2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31071336

ABSTRACT

The main aim of this study was to investigate the effects of phloretin loaded chitosan nanoparticles (PhCsNPs) on 7,12-dimethylbenz[a]anthracene (DMBA) induced experimental cancer in hamsters. Oral squamous cell carcinoma (OSCC) was induced in male golden Syrian hamsters by painting with 0.5% DMBA three times a week for 14 weeks. Varying concentration of PhCsNPs (5, 10, and 20 mg/kg b.wt.) was orally administered on alternative days to evaluate the optimum dose. The experiment design was terminated at the end of the 14th week. The development of OSCC was confirmed by histopathological and biochemical analysis (lipid peroxidation, antioxidant profile, and detoxification enzymes) in plasma, erythrocyte, buccal, and liver tissues. Significant increases in oxidation and lipid peroxidation were noticed in DMBA-painted hamsters. Oral administration of PhCsNPs in various doses on alternate days reversed the deleterious effects induced by DMBA. In addition, immunoblot analyses of PhCsNPs treatment enhanced the release of Bcl-2 associated X protein (Bax), cytochrome c, caspase-3, 9 and suppressed the B-cell lymphoma 2 (Bcl-2) expression, which the use of PhCsNPs for mitochondrial-mediated apoptosis. These findings suggest biofabricated PhCsNPs may act as a potent antioxidant and anti-carcinogenic in DMBA induced oral cancer in experimental animals.


Subject(s)
Antioxidants/metabolism , Apoptosis/drug effects , Chitosan/chemistry , Nanoparticles/chemistry , Phloretin/pharmacology , Administration, Oral , Animals , Carcinoma, Squamous Cell/chemically induced , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/pathology , Caspase 3/metabolism , Cricetinae , Cytochrome P-450 Enzyme System/metabolism , Cytochromes c/metabolism , Down-Regulation/drug effects , Lipid Peroxidation/drug effects , Male , Mouth Neoplasms/chemically induced , Mouth Neoplasms/drug therapy , Mouth Neoplasms/pathology , Phloretin/chemistry , Phloretin/therapeutic use , Proto-Oncogene Proteins c-bcl-2/metabolism , bcl-2-Associated X Protein/metabolism
18.
Food Chem Toxicol ; 129: 291-300, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31059746

ABSTRACT

Methylglyoxal (MGO), a cytotoxic factor, reacts irreversibly with the side chains of lysine, cysteine, and arginine residues in proteins to form advanced glycation end products (AGEs) which might be a major pathological factor associated with diabetic complications. Thus, it is necessary to prevent or alleviate such diseases through inhibiting the formation of AGEs or lowering these AGEs-induced cellular damages. Based on our previous work, it was known that phloretin, an apple polyphenol, can inhibit the formation of AGEs under simulated physiological conditions. In this study, we found that phloretin prevented the formation of AGEs through trapping MGO in human umbilical endothelial cells (HUVECs). The phloretin-MGO adducts were analyzed in PBS and HUVECs. Surprisingly, only 1 MGO-phloretin adduct was detected in HUVECs, which was formed within 0.5 h and metabolized eventually within 24 h. The specific phloretin-MGO adduct was synthesized and identified by MS and NMR analysis. Its anti-inflammatory effect against AGEs was further investigated together with the parent compound, phloretin, which was proved to be through RAGE/p38 MAPK/NF-κB signaling pathway. Taken together, our data indicated the positive role of phloretin-MGO adduct on phloretin's protective effects, which might offer a new insight into the action mechanism of polyphenols against AGEs-induced damages.


Subject(s)
Endothelium, Vascular/drug effects , Glycation End Products, Advanced/metabolism , Inflammation/metabolism , Phloretin/pharmacology , Pyruvaldehyde/pharmacology , Cell-Free System , Endothelium, Vascular/cytology , Endothelium, Vascular/metabolism , Human Umbilical Vein Endothelial Cells , Humans , NF-kappa B/metabolism , Phloretin/chemistry , Polyphenols/pharmacology , Pyruvaldehyde/chemistry , Receptor for Advanced Glycation End Products/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism
19.
Molecules ; 24(7)2019 Apr 03.
Article in English | MEDLINE | ID: mdl-30987239

ABSTRACT

Phloretin is a natural chalcone with antibacterial and anti-inflammatory effects. This study investigated the anti-acne activity of phloretin against Propionibacterium acnes-induced skin infection and the potential target proteins of its anti-inflammatory and antibacterial effects. Phloretin potently inhibited the growth of P. acnes and P. acnes-induced Toll-like receptor (TLR) 2-mediated inflammatory signaling in human keratinocytes. Secreted embryonic alkaline phosphatase assay confirmed that the anti-inflammatory activity of phloretin is associated with the P. acnes-stimulated TLR2-mediated NF-κB signaling pathway. Phloretin significantly decreased the level of phosphorylated c-Jun N-terminal kinase (JNK), showing a binding affinity of 1.184 × 10-5 M-1. We also found that phloretin binds with micromolar affinity to P. acnes ß-ketoacyl acyl carrier protein (ACP) synthase III (KAS III), an enzyme involved in fatty acid synthesis. Conformation-sensitive native polyacrylamide gel electrophoresis showed that phloretin reduced KAS III-mediated 3-ketoacyl ACP production by over 66%. A docking study revealed that phloretin interacts with the active sites of JNK1 and KAS III, suggesting their involvement in P. acnes-induced inflammation and their potential as targets for the antibacterial activity of phloretin. These results demonstrate that phloretin may be useful in the prevention or treatment of P. acnes infection.


Subject(s)
Anti-Bacterial Agents/pharmacology , Gram-Positive Bacterial Infections/metabolism , Gram-Positive Bacterial Infections/microbiology , Phloretin/pharmacology , Propionibacterium acnes/drug effects , Skin Diseases, Bacterial/metabolism , Skin Diseases, Bacterial/microbiology , 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/antagonists & inhibitors , 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/chemistry , 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/metabolism , Anti-Bacterial Agents/chemistry , Binding Sites , Cell Line, Tumor , Cell Survival/drug effects , Cytokines/biosynthesis , Dose-Response Relationship, Drug , Gram-Positive Bacterial Infections/drug therapy , Humans , Models, Molecular , Molecular Conformation , Molecular Structure , Phloretin/chemistry , Propionibacterium acnes/enzymology , Propionibacterium acnes/immunology , Protein Binding , Skin Diseases, Bacterial/drug therapy , Structure-Activity Relationship , Toll-Like Receptor 2/metabolism
20.
Mini Rev Med Chem ; 19(13): 1060-1067, 2019.
Article in English | MEDLINE | ID: mdl-30864525

ABSTRACT

Over the past two decades, many researchers have concluded that a diet rich in polyphenolic compounds plays an important therapeutic role in reducing the risk of cancer, cardiovascular disease, inflammation, diabetes, and other degenerative diseases. Polyphenolic compounds have been reported to be involved in neutralization of reactive oxygen species and charged radicals, and have anticarcinogenic effects, hepatoprotective effects, low-glycaemic response, and other benefits. The benefits of fruits and vegetables may be partly attributable to polyphenolic compounds, which have antioxidant and free radical scavenging properties. Fruits such as apples contain a variety of phytochemicals, including (+)-catechin and (-)-epicatechin, phlorizin, phloretin quercetin, cyanidin-3-Ogalactoside, chlorogenic acid, and p-coumaric acid, all of which are strong antioxidants. Phloretin, a natural phenolic compound, is a dihydrochalcone, which is present in the apple. It exhibits a wide variety of activities such as antioxidative, anti-inflammatory, anti-microbial, anti-allergic, anticarcinogenic, anti-thrombotic, and hepatoprotective, besides being involved in the activation of apoptotic associated gene expression and signal transduction in molecular pathways. Despite a multitude of clinical studies, new efforts are needed in clinical research to determine the complete therapeutic potential of phloretin.


Subject(s)
Antineoplastic Agents/pharmacology , Antioxidants/pharmacology , Hypoglycemic Agents/pharmacology , Phloretin/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/therapeutic use , Antioxidants/chemistry , Antioxidants/therapeutic use , Arthritis, Rheumatoid/drug therapy , Cardiovascular Diseases/drug therapy , Diabetes Mellitus/drug therapy , Humans , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/therapeutic use , Inflammation/drug therapy , Neoplasms/drug therapy , Phloretin/chemistry , Phloretin/therapeutic use
SELECTION OF CITATIONS
SEARCH DETAIL
...