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1.
BMC Genomics ; 22(1): 507, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34225670

RESUMO

BACKGROUND: Salmonella is a major bacterial pathogen associated with a large number of outbreaks of foodborne diseases. Many highly virulent serovars that cause human illness belong to Salmonella serogroup C1, and Salmonella ser. Choleraesuis is a prominent cause of invasive infections in Asia. Comparative genomic analysis in our previous study showed that two homologous genes, SC0368 and SC0595 in Salmonella ser. Choleraesuis were unique to serogroup C1. In this study, two single-deletion mutants (Δ0368 and Δ0595) and one double-deletion mutant (Δ0368Δ0595) were constructed based on the genome. All these mutants and the wild-type strain were subjected to RNA-Seq analysis to reveal functional relationships of the two serogroup C1-specific genes. RESULTS: Data from RNA-Seq indicated that deletion of SC0368 resulted in defects in motility through repression of σ28 in flagellar regulation Class 3. Consistent with RNA-Seq data, results from transmission electron microcopy (TEM) showed that flagella were not present in △0368 and △0368△0595 mutants resulting in both swimming and swarming defects. Interestingly, the growth rates of two non-motile mutants △0368 and △0368△0595 were significantly greater than the wild-type, which may be associated with up-regulation of genes encoding cytochromes, enhancing bacterial proliferation. Moreover, the △0595 mutant was significantly more invasive in Caco-2 cells as shown by bacterial enumeration assays, and the expression of lipopolysaccharide (LPS) core synthesis-related genes (rfaB, rfaI, rfaQ, rfaY, rfaK, rfaZ) was down-regulated only in the △0368△0595 mutant. In addition, this study also speculated that these two genes might be contributing to serotype conversion for Salmonella C1 serogroup based on their apparent roles in biosynthesis of LPS and the flagella. CONCLUSION: A combination of biological and transcriptomic (RNA-Seq) analyses has shown that the SC0368 and SC0595 genes are involved in biosynthesis of flagella and complete LPS, as well as in bacterial growth and virulence. Such information will aid to revealing the role of these specific genes in bacterial physiology and evolution within the serogroup C1.


Assuntos
Flagelos , Salmonella , Ásia , Proteínas de Bactérias/genética , Células CACO-2 , Flagelos/genética , Humanos , Sorogrupo
2.
Talanta ; 233: 122494, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215112

RESUMO

Titanium dioxide nanoparticles (TiO2 NPs) are widely used in industry as a white pigment (paints, paper industry and toothpastes), photocatalysts (environmental decontamination and photovoltaic cells), inorganic UV filter (sunscreens and personal care products) and as a food additive (E171) and antimicrobial food packaging material. Silver nanoparticles (Ag NPs) are used in photonics, microelectronics, catalysis and medicine due to their catalytic activity, magnetic and optical polarizability, electrical and thermal conductivities and enhanced Raman scattering. They also have antibacterial, antifungal and antiviral activities, as well as anti-inflammatory potential. The huge increase in the use of nano-based products, mainly metallic NPs, implies the presence of nanomaterials in the environment, and hence, the unintentional human ingestion through water or foods (gastrointestinal tract is the main pathway of NPs intake in humans). The presence of TiO2 NPs and Ag NPs in seafood samples was firstly established using an ultrasound assisted enzymatic hydrolysis procedure and sp-ICP-MS analysis. Several clams, cockles, mussels, razor clams, oysters and variegated scallops, which contain TiO2 NPs and Ag NPs, were subjected to an in vitro digestion process simulating human gastrointestinal digestion in the stomach and in the small and large intestine to determine the bioaccessibility of these NPs. Caco-2 cells were selected as model of human intestinal epithelium for transport studies because of the development of membrane transporters that are responsible for the uptake of chemicals. Parameters as transepithelial electrical resistance (TEER) and permeability of Lucifer Yellow were studied for establishing cell monolayer integrity. TiO2 NPs and Ag NPs transport as well as total Ti and Ag concentrations passing through the gastrointestinal epithelial barrier model (0-2 h) were assessed by sp-ICP-MS and ICP-MS in several molluscs.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Células CACO-2 , Trato Gastrointestinal , Humanos , Alimentos Marinhos , Prata , Titânio
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(4): 570-576, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34323033

RESUMO

Objective: To construct solid lipid nanoparticle (SNPs) drug delivery system loaded with peptide and protein drugs by using mixedsolvents, to study the transcytosis mechanisms of SNPs across intestinal epithelial cells, and to improve the endocytosis and transcytosis efficiency of peptide and protein drugs. Methods: The formulation of insulin-loaded water-in-oil-in-water solid lipid nanoparticles (INS-SNPs) was prepared by using a methanol-chloroform mixed solvent. The formulation was optimized with the single factor screening method. The optimized INS-SNPs were then characterized in terms of their morphology, stability and drug release properties. The cytotoxicity, cellular uptake and endocytosis mechanisms of INS-SNPs were then assessed on Caco-2 cells. The transcytosis efficiency of INS-SNPs was finally evaluated by using cellular monolayer in Transwell ® insert. Results: The size, zeta potentials and drug loading efficiency of the optimized INS-SNPs were observed to be (145.4±0.5) nm, (-12.9±0.2) mV and (7.93±0.02)%, respectively. INS-SNPs were then shown to maintain desirable colloidal stability and sustained release of insulin in the simulated intestinal fluid. It was revealed that the cellular uptake of INS-SNPs reached its maximum after cellular incubation for 2 hours and was 1.53-fold higher than that of free insulin. Investigation of the endocytic mechanism revealed that INS-SNPs enter intestinal epithelial cells mainly through the clathrin-mediated and caveolae-mediated endocytosis pathways. Further investigation revealed that the amount of INS-SNPs permeating the cell monolayers was 1.54-fold higher than that of free insulin, which was comparable to the increase in their cellular uptake efficiency, indicating that INS-SNPs displayed enhanced absorption across the intestinal epithelium. Conclusion: The INS-SNPs prepared with mixed solvents in this study could significantly enhance the transcytosis efficiency of peptide and protein drugs, displaying great potentials in the application of oral drug delivery. This study may provide information and reference for the designing of efficient oral nano-drug delivery system in the future.


Assuntos
Insulina , Nanopartículas , Administração Oral , Células CACO-2 , Portadores de Fármacos , Humanos , Lipídeos , Transcitose
4.
Nutrients ; 13(6)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208504

RESUMO

The soybean allergen Gly m 4 is known to cause severe allergic reactions including anaphylaxis, unlike other Bet v 1 homologues, which induce mainly local allergic reactions. In the present study, we aimed to investigate whether the food Bet v 1 homologue Gly m 4 can be a sensitizer of the immune system. Susceptibility to gastrointestinal digestion was assessed in vitro. Transport through intestinal epithelium was estimated using the Caco-2 monolayer. Cytokine response of different immunocompetent cells was evaluated by using Caco-2/Immune cells co-culture model. Absolute levels of 48 cytokines were measured by multiplex xMAP technology. It was shown that Gly m 4 can cross the epithelial barrier with a moderate rate and then induce production of IL-4 by mature dendritic cells in vitro. Although Gly m 4 was shown to be susceptible to gastrointestinal enzymes, some of its proteolytic fragments can selectively cross the epithelial barrier and induce production of Th2-polarizing IL-5, IL-10, and IL-13, which may point at the presence of the T-cell epitope among the crossed fragments. Our current data indicate that Gly m 4 can potentially be a sensitizer of the immune system, and intercommunication between immunocompetent and epithelial cells may play a key role in the sensitization process.


Assuntos
Antígenos de Plantas/farmacologia , Hipersensibilidade Alimentar/terapia , Imunização/métodos , Antígenos de Plantas/imunologia , Células CACO-2/efeitos dos fármacos , Células CACO-2/imunologia , Quimiocinas/metabolismo , Técnicas de Cocultura , Citocinas/metabolismo , Escherichia coli/metabolismo , Hipersensibilidade Alimentar/imunologia , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Modelos Biológicos , Organismos Geneticamente Modificados , Células THP-1/efeitos dos fármacos , Células THP-1/imunologia
5.
Biomed Pharmacother ; 139: 111684, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34243632

RESUMO

PPARγ regulate the expression of genes involved in peripheral insulin sensitivity, adipogenesis, and glucose homeostasis. Moreover, PPARγ agonists, such as pioglitazone and rosiglitazone, are used in the treatment of various diseases, e.g. diabetes (type II), atherosclerosis, inflammatory skin disease, and some types of cancers. PPARγ agonists have also been found to reduce oxidative-stress (OS) and OS-induced apoptosis. Therefore, the aim of the present study was to evaluate the impact of 4-thiazolidinone-based derivatives Les-2194, Les-3377, and Les-3640 on the expression of antioxidant enzymes in human squamous cell carcinoma (SCC-15), lung carcinoma (A549), colon adenocarcinoma (CACO-2), and skin fibroblast (BJ) cell lines. After 24 h of exposure, Les-2194 caused an increase in ROS production in the SCC-15 and CACO-2 cell lines; however, no changes in caspase-3 activity and metabolic activity were observed. Nevertheless, the Ki67 level was significantly decreased. Les-3377 was able to increase ROS production in all tested cell lines, but no impact on metabolic activity and caspase-3 activity were noticed. In turn, Les-3640 was able to induce ROS overproduction in BJ, SCC-15, and CACO-2 and did not affect metabolic activity. However, an increase in caspase-3 activity was observed at the 10 µM concentration in all tested cell lines. All tested compounds were able to influence CAT and SOD1 expression and decreased (Les-2194 in the BJ cells) or increased (Les-3640 in the SCC-15 and CACO-2 cells) PPARγ expression.


Assuntos
Antioxidantes/metabolismo , Pioglitazona/farmacologia , Rosiglitazona/farmacologia , Tiazolidinas/farmacologia , Células A549 , Apoptose/efeitos dos fármacos , Células CACO-2 , Caspase 3/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Neoplasias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , PPAR gama/metabolismo , Espécies Reativas de Oxigênio/metabolismo
6.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207335

RESUMO

Several medical plants, such as Passiflora incarnata L., contain C-glycosylated flavonoids, which may contribute to their efficacy. Information regarding the bioavailability and metabolism of these compounds is essential, but not sufficiently available. Therefore, the metabolism of the C-glycosylated flavones orientin, isoorientin, schaftoside, isoschaftoside, vitexin, and isovitexin was investigated using the Caco-2 cell line as an in vitro intestinal and epithelial metabolism model. Isovitexin, orientin, and isoorientin showed broad ranges of phase I and II metabolites containing hydroxylated, methoxylated, and sulfated compounds, whereas schaftoside, isoschaftoside, and vitexin underwent poor metabolism. All metabolites were identified via UHPLC-MS or UHPLC-MS/MS using compound libraries containing all conceivable metabolites. Some structures were confirmed via UHPLC-MS experiments with reference compounds after a cleavage reaction using glucuronidase and sulfatase. Of particular interest is the observed cleavage of the C-C bonds between sugar and aglycone residues in isovitexin, orientin, and isoorientin, resulting in unexpected glucuronidated or sulfated luteolin and apigenin derivatives. These findings indicate that C-glycosidic flavones can be highly metabolized in the intestine. In particular, flavonoids with ortho-dihydroxy groups showed sulfated metabolites. The identified glucuronidated or sulfated aglycones demonstrate that enzymes expressed by Caco-2 cells are able to potentially cleave C-C bonds in vitro.


Assuntos
Flavonoides/metabolismo , Passiflora/química , Células CACO-2 , Enterócitos/metabolismo , Flavonoides/química , Humanos
7.
Int J Mol Sci ; 22(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201817

RESUMO

The usefulness of anti-inflammatory drugs as an adjunct therapy to improve outcomes in COVID-19 patients is intensely discussed in this paper. Willow bark (Salix cortex) has been used for centuries to relieve pain, inflammation, and fever. Its main active ingredient, salicin, is metabolized in the human body into salicylic acid, the precursor of the commonly used pain drug acetylsalicylic acid (ASA). Here, we report on the in vitro anti-inflammatory efficacy of two methanolic Salix extracts, standardized to phenolic compounds, in comparison to ASA in the context of a SARS-CoV-2 peptide challenge. Using SARS-CoV-2 peptide/IL-1ß- or LPS-activated human PBMCs and an inflammatory intestinal Caco-2/HT29-MTX co-culture, Salix extracts, and ASA concentration-dependently suppressed prostaglandin E2 (PGE2), a principal mediator of inflammation. The inhibition of COX-2 enzyme activity, but not protein expression was observed for ASA and one Salix extract. In activated PBMCs, the suppression of relevant cytokines (i.e., IL-6, IL-1ß, and IL-10) was seen for both Salix extracts. The anti-inflammatory capacity of Salix extracts was still retained after transepithelial passage and liver cell metabolism in an advanced co-culture model system consisting of intestinal Caco-2/HT29-MTX cells and differentiated hepatocyte-like HepaRG cells. Taken together, our in vitro data suggest that Salix extracts might present an additional anti-inflammatory treatment option in the context of SARS-CoV-2 peptides challenge; however, more confirmatory data are needed.


Assuntos
Anti-Inflamatórios/farmacologia , Aspirina/farmacologia , COVID-19/tratamento farmacológico , COVID-19/imunologia , Extratos Vegetais/farmacologia , Anti-Inflamatórios/química , Álcoois Benzílicos/metabolismo , COVID-19/virologia , Células CACO-2 , Ciclo-Oxigenase 2/efeitos dos fármacos , Citocinas/metabolismo , Dinoprostona/metabolismo , Glucosídeos/metabolismo , Células HT29 , Humanos , Inflamação , Leucócitos Mononucleares/efeitos dos fármacos , Lipopolissacarídeos/imunologia , Casca de Planta/química , Extratos Vegetais/química , SARS-CoV-2/imunologia
8.
Int J Mol Sci ; 22(11)2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34198897

RESUMO

The introduction of metallic nanoparticles (mNPs) into the diet is a matter of concern for human health. In particular, their effect on the gastrointestinal tract may potentially lead to the increased passage of gluten peptides and the activation of the immune response. In consequence, dietary mNPs could play a role in the increasing worldwide celiac disease (CeD) incidence. We evaluated the potential synergistic effects that peptic-tryptic-digested gliadin (PT) and the most-used food mNPs may induce on the intestinal mucosa. PT interaction with mNPs and their consequent aggregation was detected by transmission electron microscopy (TEM) analyses and UV-Vis spectra. In vitro experiments on Caco-2 cells proved the synergistic cytotoxic effect of PT and mNPs, as well as alterations in the monolayer integrity and tight junction proteins. Exposure of duodenal biopsies to gliadin plus mNPs triggered cytokine production, but only in CeD biopsies. These results suggest that mNPs used in the food sector may alter intestinal homeostasis, thus representing an additional environmental risk factor for the development of CeD.


Assuntos
Doença Celíaca/dietoterapia , Dieta , Glutens/metabolismo , Nanopartículas/uso terapêutico , Biópsia , Células CACO-2 , Doença Celíaca/imunologia , Doença Celíaca/metabolismo , Doença Celíaca/patologia , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/metabolismo , Homeostase/imunologia , Humanos , Imunidade/efeitos dos fármacos , Imunidade/imunologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Nanopartículas/metabolismo , Triticum/efeitos adversos
9.
Molecules ; 26(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202245

RESUMO

Cancer-based magnetic theranostics has gained significant interest in recent years and can contribute as an influential archetype in the effective treatment of cancer. Owing to their excellent biocompatibility, minute sizes and reactive functional surface groups, magnetic nanoparticles (MNPs) are being explored as potential drug delivery systems. In this study, MgFe2O4 ferrite MNPs were evaluated for their potential to augment the delivery of the anticancer drug doxorubicin (DOX). These MNPs were successfully synthesized by the glycol-thermal method and functionalized with the polymers; chitosan (CHI), polyvinyl alcohol (PVA) and polyethylene glycol (PEG), respectively, as confirmed by Fourier transform infrared (FTIR) spectroscopy. X-ray diffraction (XRD) confirmed the formation of the single-phase cubic spinel structures while vibrating sample magnetometer (VSM) analysis confirmed the superparamagnetic properties of all MNPs. Transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA) revealed small, compact structures with good colloidal stability. CHI-MNPs had the highest DOX encapsulation (84.28%), with the PVA-MNPs recording the lowest encapsulation efficiency (59.49%). The 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide (MTT) cytotoxicity assays conducted in the human embryonic kidney (HEK293), colorectal adenocarcinoma (Caco-2), and breast adenocarcinoma (SKBR-3) cell lines showed that all the drug-free polymerized MNPs promoted cell survival, while the DOX loaded MNPs significantly reduced cell viability in a dose-dependent manner. The DOX-CHI-MNPs possessed superior anticancer activity (<40% cell viability), with approximately 85.86% of the drug released after 72 h in a pH-responsive manner. These MNPs have shown good potential in enhancing drug delivery, thus warranting further optimizations and investigations.


Assuntos
Antibióticos Antineoplásicos , Doxorrubicina , Portadores de Fármacos , Nanopartículas de Magnetita , Neoplasias/tratamento farmacológico , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacologia , Células CACO-2 , Quitosana/química , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Compostos Férricos/química , Células HEK293 , Humanos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapêutico , Neoplasias/metabolismo , Neoplasias/patologia , Polietilenoglicóis/química , Álcool de Polivinil/química
10.
Molecules ; 26(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34208810

RESUMO

Currently, on an industrial scale, synthetic colorants are used in many fields, as well as those extracted with conventional organic solvents (COSs), leading to several environmental issues. Therefore, we developed a sustainable extraction and purification method mediated by ionic liquids (IL), which is considered an alternative high-performance replacement for COSs. Carotenoids are natural pigments with low bioaccessibility (BCT) and bioavailability (BV) but with huge importance to health. To investigate if the BCT and cellular uptake of the carotenoids are modified by the extraction method, we conducted a comparison assay between both extraction procedures (IL vs. COS). For this, we used the Amazonian fruit Bactris gasipaes, a rich source of pro-vitamin A carotenoids, to obtain the extract, which was emulsified and subjected to an in vitro digestion model followed by the Caco-2 cell absorption assay. The bioaccessibility of carotenoids using IL was better than those using COS (33.25%, and 26.84%, respectively). The cellular uptake of the carotenoids extracted with IL was 1.4-fold higher than those extracted using COS. Thus, IL may be a feasible alternative as extraction solvent in the food industry, replacing COS, since, in this study, no IL was present in the final extract.


Assuntos
Arecaceae/química , Carotenoides , Frutas/química , Líquidos Iônicos/química , Extratos Vegetais/química , Disponibilidade Biológica , Células CACO-2 , Carotenoides/química , Carotenoides/isolamento & purificação , Carotenoides/farmacocinética , Carotenoides/farmacologia , Humanos
11.
Molecules ; 26(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209170

RESUMO

BACKGROUND: This study aimed to produce, purify, structurally elucidate, and explore the biological activities of metabolites produced by Streptomyces (S.) griseus isolate KJ623766, a recovered soil bacterium previously screened in our lab that showed promising cytotoxic activities against various cancer cell lines. METHODS: Production of cytotoxic metabolites from S. griseus isolate KJ623766 was carried out in a 14L laboratory fermenter under specified optimum conditions. Using a 3-(4,5-dimethylthazol-2-yl)-2,5-diphenyl tetrazolium-bromide assay, the cytotoxic activity of the ethyl acetate extract against Caco2 and Hela cancer cell lines was determined. Bioassay-guided fractionation of the ethyl acetate extract using different chromatographic techniques was used for cytotoxic metabolite purification. Chemical structures of the purified metabolites were identified using mass, 1D, and 2D NMR spectroscopic analysis. RESULTS: Bioassay-guided fractionation of the ethyl acetate extract led to the purification of two cytotoxic metabolites, R1 and R2, of reproducible amounts of 5 and 1.5 mg/L, respectively. The structures of R1 and R2 metabolites were identified as ß- and γ-rhodomycinone with CD50 of 6.3, 9.45, 64.8 and 9.11, 9.35, 67.3 µg/mL against Caco2, Hela and Vero cell lines, respectively. Values were comparable to those of the positive control doxorubicin. CONCLUSIONS: This is the first report about the production of ß- and γ-rhodomycinone, two important scaffolds for synthesis of anticancer drugs, from S. griseus.


Assuntos
Antibióticos Antineoplásicos , Streptomyces griseus , Animais , Antraciclinas/química , Antraciclinas/isolamento & purificação , Antraciclinas/metabolismo , Antraciclinas/farmacologia , Antibióticos Antineoplásicos/biossíntese , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/isolamento & purificação , Antibióticos Antineoplásicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Células CACO-2 , Chlorocebus aethiops , Células HeLa , Humanos , Streptomyces griseus/química , Streptomyces griseus/metabolismo , Células Vero
12.
Molecules ; 26(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209325

RESUMO

Polysaccharides can form interfacial complexes with proteins to form emulsions with enhanced stability. We assessed the effect of adding gum guar or gum arabic to egg yolk/fish oil emulsions. The emulsions were produced using simple or high-pressure homogenization, stored for up to 10 days at 45 °C, and characterized for their particle size and distribution, viscosity, encapsulation efficiency, oxidative stability, and cytotoxicity. Emulsions containing gum guar and/or triglycerides had the highest viscosity. There was no significant difference in the encapsulation efficiency of emulsions regardless of the polysaccharide used. However, emulsions containing gum arabic displayed a bridging flocculation effect, resulting in less stability over time compared to those using gum guar. Emulsions produced using high-pressure homogenization displayed a narrower size distribution and higher stability. The formation of peroxides and propanal was lower in emulsions containing gum guar and was attributed to the surface oil. No significant toxicity toward Caco-2 cells was found from the emulsions over time. On the other hand, after 10 days of storage, nonencapsulated fish oil reduced the cell viability to about 80%. The results showed that gum guar can increase the particle stability of egg yolk/fish oil emulsions and decrease the oxidation rate of omega-3 fatty acids.


Assuntos
Gema de Ovo/química , Óleos de Peixe/química , Galactanos/química , Goma Arábica/química , Mananas/química , Gomas Vegetais/química , Polissacarídeos/química , Células CACO-2 , Emulsões , Óleos de Peixe/farmacologia , Galactanos/farmacologia , Goma Arábica/farmacologia , Humanos , Mananas/farmacologia , Oxirredução , Gomas Vegetais/farmacologia , Polissacarídeos/farmacologia
13.
J Agric Food Chem ; 69(28): 7979-7989, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34251199

RESUMO

Wheat protein is the most consumed plant protein in our diet, and there is an increased prevalence of wheat/gluten intolerance and adherence to a gluten-free diet in many countries. Despite the known immunodominant effect of undigested gliadin peptides responsible for gluten-related intolerance, it remains unclear if and how gliadin peptides self-assemble into ordered nanostructures during gastrointestinal digestion, as well as their biological impact on the mucus barrier function. In this study, we purified undigestible gliadin peptide nanoparticles (UGPNs) by ultracentrifugation and characterized their structural and physiochemical properties. The results demonstrate that the UGPNs are self-assembled nanostructures generated by cationic amino acids (Lys and Arg)-capped surfactant-like peptides (SLPs), mainly derived from γ-gliadin and α-gliadin. SLPs trigger the concentration-dependent self-assembly driven by ß-sheet conformational transitions above their critical aggregation concentration (cac, ∼0.1 mg/mL). UGPNs can easily penetrate the mucus layer in Caco-2/HT29-MTX cocultures with a high Papp value (∼5.7 × 10-6 cm/s) and reduce the production and thickness of the mucus layer driven by intestinal epithelial cell damage. Isothermal titration calorimetry and Langmuir monolayer studies indicate that the self-assembled state of UGPNs significantly affects their binding to DPPC/DOPE lipid membrane models. These results highlight the relevance of the self-assembly of gliadin peptides as a trigger of mucosal inflammation-related wheat/gluten intolerance.


Assuntos
Doença Celíaca , Nanopartículas , Células CACO-2 , Células Epiteliais , Gliadina , Humanos , Muco , Peptídeos
14.
Molecules ; 26(11)2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204150

RESUMO

The purpose of this study was to develop mixed polymeric micelles with high drug loading capacity to improve the oral bioavailability of icaritin with Soluplus® and Poloxamer 407 using a creative acid-base shift (ABS) method, which exhibits the advantages of exclusion of organic solvents, high drug loading and ease of scaling-up. The feasibility of the ABS method was successfully demonstrated by studies of icaritin-loaded polymeric micelles (IPMs). The prepared IPMs were characterized to have a spherical shape with a size of 72.74 ± 0.51 nm, and 13.18% drug loading content. In vitro release tests confirmed the faster release of icaritin from IPMs compared to an oil suspension. Furthermore, bioavailability of icaritin in IPMs in beagle dogs displayed a 14.9-fold increase when compared with the oil suspension. Transcellular transport studies of IPMs across Caco-2 cell monolayers confirmed that the IPMs were endocytosed in their intact forms through macropinocytosis, clathrin-, and caveolae-mediated pathways. In conclusion, the results suggested that the mixed micelles of Soluplus® and Poloxamer 407 could be a feasible drug delivery system to enhance oral bioavailability of icaritin, and the ABS method might be a promising technology for the preparation of polymeric micelles to encapsulate poorly water-soluble weakly acidic and alkaline drugs.


Assuntos
Flavonoides/administração & dosagem , Poloxâmero/química , Polietilenoglicóis/química , Polivinil/química , Transdução de Sinais/efeitos dos fármacos , Administração Oral , Animais , Disponibilidade Biológica , Células CACO-2 , Cavéolas/metabolismo , Clatrina/metabolismo , Cães , Estudos de Viabilidade , Flavonoides/síntese química , Flavonoides/farmacocinética , Humanos , Masculino , Micelas , Nanopartículas , Tamanho da Partícula
15.
Med Microbiol Immunol ; 210(4): 235-244, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34196781

RESUMO

The novel coronavirus SARS-CoV-2 is the causative agent of the acute respiratory disease COVID-19, which has become a global concern due to its rapid spread. Laboratory work with SARS-CoV-2 in a laboratory setting was rated to biosafety level 3 (BSL-3) biocontainment level. However, certain research applications in particular in molecular biology require incomplete denaturation of the proteins, which might cause safety issues handling contaminated samples. In this study, we evaluated lysis buffers that are commonly used in molecular biological laboratories for their ability to inactivate SARS-CoV-2. In addition, viral stability in cell culture media at 4 °C and on display glass and plastic surfaces used in laboratory environment was analyzed. Furthermore, we evaluated chemical and non-chemical inactivation methods including heat inactivation, UV-C light, addition of ethanol, acetone-methanol, and PFA, which might be used as a subsequent inactivation step in the case of insufficient inactivation. We infected susceptible Caco-2 and Vero cells with pre-treated SARS-CoV-2 and determined the tissue culture infection dose 50 (TCID50) using crystal violet staining and microscopy. In addition, lysates of infected cells and virus containing supernatant were subjected to RT-qPCR analysis. We have found that guanidine thiocyanate and most of the tested detergent containing lysis buffers were effective in inactivation of SARS-CoV-2, however, the M-PER lysis buffer containing a proprietary detergent failed to inactivate the virus. In conclusion, careful evaluation of the used inactivation methods is required especially for non-denaturing buffers. Additional inactivation steps might be necessary before removal of lysed viral samples from BSL-3.


Assuntos
Anti-Infecciosos/farmacologia , COVID-19/prevenção & controle , COVID-19/virologia , Guanidinas/farmacologia , SARS-CoV-2/efeitos dos fármacos , Tiocianatos/farmacologia , Inativação de Vírus , Animais , Células CACO-2 , Linhagem Celular , Chlorocebus aethiops , Contenção de Riscos Biológicos , Humanos , RNA Viral , Reação em Cadeia da Polimerase em Tempo Real , SARS-CoV-2/fisiologia , Manejo de Espécimes/métodos , Fatores de Tempo , Células Vero
16.
Int J Mol Sci ; 22(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208517

RESUMO

Superoxide dismutase 3 (SOD3), also known as extracellular superoxide dismutase, is an enzyme that scavenges reactive oxygen species (ROS). It has been reported that SOD3 exerts anti-inflammatory abilities in several immune disorders. However, the effect of SOD3 and the underlying mechanism in inflammatory bowel disease (IBD) have not been uncovered. Therefore, in the present study, we investigated whether SOD3 can protect intestinal cells or organoids from inflammation-mediated epithelial damage. Cells or mice were treated with SOD3 protein or SOD3-transduced mesenchymal stem cells (MSCs). Caco-2 cells or intestinal organoids stimulated with pro-inflammatory cytokines were used to evaluate the protective effect of SOD3 on epithelial junctional integrity. Dextran sulfate sodium (DSS)-induced colitis mice received SOD3 or SOD3-transduced MSCs (SOD3-MSCs), and were assessed for severity of disease and junctional protein expression. The activation of the mitogen-activated protein kinase (MAPK) pathway and elevated expression of cytokine-encoding genes decreased in TNF-α-treated Caco-2 cells or DSS-induced colitis mice when treated with SOD3 or SOD3-MSCs. Moreover, the SOD3 supply preserved the expression of tight junction (ZO-1, occludin) or adherence junction (E-cadherin) proteins when inflammation was induced. SOD3 also exerted a protective effect against cytokine- or ROS-mediated damage to intestinal organoids. These results indicate that SOD3 can effectively alleviate enteritis symptoms by maintaining the integrity of epithelial junctions and regulating inflammatory- and oxidative stress.


Assuntos
Colite/etiologia , Colite/metabolismo , Mucosa Intestinal/metabolismo , Células-Tronco Mesenquimais/metabolismo , Superóxido Dismutase/genética , Junções Íntimas/metabolismo , Animais , Biomarcadores , Células CACO-2 , Colite/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Humanos , Imuno-Histoquímica , Mediadores da Inflamação/metabolismo , Células-Tronco Mesenquimais/citologia , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Junções Íntimas/patologia
17.
Viruses ; 13(7)2021 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206990

RESUMO

Innate immunity during acute infection plays a critical role in the disease severity of severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), and is likely to contribute to COVID-19 disease outcomes. Defensins are highly abundant innate immune factors in neutrophils and epithelial cells, including intestinal Paneth cells, and exhibit antimicrobial and immune-modulatory activities. In this study, we investigated the effects of human α- and ß-defensins and RC101, a θ-defensin analog, on SARS-CoV-2 infection. We found that human neutrophil peptides (HNPs) 1-3, human defensin (HD) 5 and RC101 exhibited potent antiviral activity against pseudotyped viruses expressing SARS-CoV-2 spike proteins. HNP4 and HD6 had weak anti-SARS-CoV-2 activity, whereas human ß-defensins (HBD2, HBD5 and HBD6) had no effect. HNP1, HD5 and RC101 also inhibited infection by replication-competent SARS-CoV-2 viruses and SARS-CoV-2 variants. Pretreatment of cells with HNP1, HD5 or RC101 provided some protection against viral infection. These defensins did not have an effect when provided post-infection, indicating their effect was directed towards viral entry. Indeed, HNP1 inhibited viral fusion but not the binding of the spike receptor-binding domain to hACE2. The anti-SARS-CoV-2 effect of defensins was influenced by the structure of the peptides, as linear unstructured forms of HNP1 and HD5 lost their antiviral function. Pro-HD5, the precursor of HD5, did not block infection by SARS-CoV-2. High virus titers overcame the effect of low levels of HNP1, indicating that defensins act on the virion. HNP1, HD5 and RC101 also blocked viral infection of intestinal and lung epithelial cells. The protective effects of defensins reported here suggest that they may be useful additives to the antivirus arsenal and should be thoroughly studied.


Assuntos
Defensinas/farmacologia , SARS-CoV-2/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos , Células A549 , Células CACO-2 , Defensinas/classificação , Células Epiteliais/virologia , Células HEK293 , Células HeLa , Humanos , SARS-CoV-2/fisiologia
18.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34210022

RESUMO

Food additive amorphous silicon dioxide (SiO2) particles are manufactured by two different methods-precipitated and fumed procedures-which can induce different physicochemical properties and biological fates. In this study, precipitated and fumed SiO2 particles were characterized in terms of constituent particle size, hydrodynamic diameter, zeta potential, surface area, and solubility. Their fates in intestinal cells, intestinal barriers, and tissues after oral administration in rats were determined by optimizing Triton X-114-based cloud point extraction (CPE). The results demonstrate that the constituent particle sizes of precipitated and fumed SiO2 particles were similar, but their aggregate states differed from biofluid types, which also affect dissolution properties. Significantly higher cellular uptake, intestinal transport amount, and tissue accumulation of precipitated SiO2 than of fumed SiO2 was found. The intracellular fates of both types of particles in intestinal cells were primarily particle forms, but slowly decomposed into ions during intestinal transport and after distribution in the liver, and completely dissolved in the bloodstream and kidneys. These findings will provide crucial information for understanding and predicting the potential toxicity of food additive SiO2 after oral intake.


Assuntos
Intestinos/química , Dióxido de Silício/administração & dosagem , Dióxido de Silício/síntese química , Administração Oral , Animais , Análise Química do Sangue , Células CACO-2 , Linhagem Celular Tumoral , Precipitação Química , Feminino , Humanos , Intestinos/citologia , Rim/química , Fígado/química , Nanopartículas , Octoxinol/química , Tamanho da Partícula , Ratos , Dióxido de Silício/química , Dióxido de Silício/farmacocinética , Solubilidade
19.
Sci Signal ; 14(690)2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34230209

RESUMO

Inorganic polyphosphates (polyPs) are linear polymers composed of repeated phosphate (PO4 3-) units linked together by multiple high-energy phosphoanhydride bonds. In addition to being a source of energy, polyPs have cytoprotective and antiviral activities. Here, we investigated the antiviral activities of long-chain polyPs against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In molecular docking analyses, polyPs interacted with several conserved amino acid residues in angiotensin-converting enzyme 2 (ACE2), the host receptor that facilitates virus entry, and in viral RNA-dependent RNA polymerase (RdRp). ELISA and limited proteolysis assays using nano- LC-MS/MS mapped polyP120 binding to ACE2, and site-directed mutagenesis confirmed interactions between ACE2 and SARS-CoV-2 RdRp and identified the specific amino acid residues involved. PolyP120 enhanced the proteasomal degradation of both ACE2 and RdRp, thus impairing replication of the British B.1.1.7 SARS-CoV-2 variant. We thus tested polyPs for functional interactions with the virus in SARS-CoV-2-infected Vero E6 and Caco2 cells and in primary human nasal epithelial cells. Delivery of a nebulized form of polyP120 reduced the amounts of viral positive-sense genomic and subgenomic RNAs, of RNA transcripts encoding proinflammatory cytokines, and of viral structural proteins, thereby presenting SARS-CoV-2 infection in cells in vitro.


Assuntos
Antivirais/farmacologia , COVID-19/tratamento farmacológico , Polifosfatos/farmacologia , SARS-CoV-2/efeitos dos fármacos , Administração por Inalação , Sequência de Aminoácidos , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Antivirais/administração & dosagem , Antivirais/química , COVID-19/metabolismo , COVID-19/virologia , Células CACO-2 , Chlorocebus aethiops , RNA-Polimerase RNA-Dependente de Coronavírus/química , RNA-Polimerase RNA-Dependente de Coronavírus/genética , RNA-Polimerase RNA-Dependente de Coronavírus/metabolismo , Citocinas/metabolismo , Células HEK293 , Interações entre Hospedeiro e Microrganismos/efeitos dos fármacos , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Técnicas In Vitro , Modelos Biológicos , Simulação de Acoplamento Molecular , Nebulizadores e Vaporizadores , Polifosfatos/administração & dosagem , Polifosfatos/química , Complexo de Endopeptidases do Proteassoma/metabolismo , Domínios e Motivos de Interação entre Proteínas , Proteólise/efeitos dos fármacos , RNA Viral/genética , RNA Viral/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Homologia de Sequência de Aminoácidos , Transdução de Sinais/efeitos dos fármacos , Células Vero , Replicação Viral/efeitos dos fármacos
20.
Cells ; 10(6)2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200372

RESUMO

Coronaviruses such as SARS-CoV-2, which is responsible for COVID-19, depend on virus spike protein binding to host cell receptors to cause infection. The SARS-CoV-2 spike protein binds primarily to ACE2 on target cells and is then processed by membrane proteases, including TMPRSS2, leading to viral internalisation or fusion with the plasma membrane. It has been suggested, however, that receptors other than ACE2 may be involved in virus binding. We have investigated the interactions of recombinant versions of the spike protein with human epithelial cell lines that express low/very low levels of ACE2 and TMPRSS2 in a proxy assay for interaction with host cells. A tagged form of the spike protein containing the S1 and S2 regions bound in a temperature-dependent manner to all cell lines, whereas the S1 region alone and the receptor-binding domain (RBD) interacted only weakly. Spike protein associated with cells independently of ACE2 and TMPRSS2, while RBD required the presence of high levels of ACE2 for interaction. As the spike protein has previously been shown to bind heparin, a soluble glycosaminoglycan, we tested the effects of various heparins on ACE2-independent spike protein interaction with cells. Unfractionated heparin inhibited spike protein interaction with an IC50 value of <0.05 U/mL, whereas two low-molecular-weight heparins were less effective. A mutant form of the spike protein, lacking the arginine-rich putative furin cleavage site, interacted only weakly with cells and had a lower affinity for unfractionated and low-molecular-weight heparin than the wild-type spike protein. This suggests that the furin cleavage site might also be a heparin-binding site and potentially important for interactions with host cells. The glycosaminoglycans heparan sulphate and dermatan sulphate, but not chondroitin sulphate, also inhibited the binding of spike protein, indicating that it might bind to one or both of these glycosaminoglycans on the surface of target cells.


Assuntos
Enzima de Conversão de Angiotensina 2/fisiologia , Células Epiteliais/metabolismo , Heparina/farmacologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Células A549 , Enzima de Conversão de Angiotensina 2/genética , Animais , Sítios de Ligação/efeitos dos fármacos , Sítios de Ligação/genética , Células CACO-2 , Linhagem Celular , Chlorocebus aethiops , Dermatan Sulfato/farmacologia , Regulação para Baixo/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/virologia , Glicosaminoglicanos/farmacologia , Células HEK293 , Células HaCaT , Heparitina Sulfato/farmacologia , Humanos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/genética , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/química , Células Vero , Internalização do Vírus/efeitos dos fármacos
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