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1.
Int J Mol Sci ; 25(11)2024 May 28.
Article in English | MEDLINE | ID: mdl-38892094

ABSTRACT

Alzheimer's Disease (AD), a prevalent neurodegenerative disorder, is the primary cause of dementia. Despite significant advancements in neuroscience, a definitive cure or treatment for this debilitating disease remains elusive. A notable characteristic of AD is oxidative stress, which has been identified as a potential therapeutic target. Polyphenols, secondary metabolites of plant origin, have attracted attention due to their potent antioxidant properties. Epidemiological studies suggest a correlation between the consumption of polyphenol-rich foods and the prevention of chronic diseases, including neurodegenerative disorders, which underscores the potential of polyphenols as a therapeutic strategy in AD management. Hence, this comprehensive review focuses on the diverse roles of polyphenols in AD, with a particular emphasis on neuroprotective potential. Scopus, ScienceDirect, and Google Scholar were used as leading databases for study selection, from 2018 to late March 2024. Analytical chemistry serves as a crucial tool for characterizing polyphenols, with a nuanced exploration of their extraction methods from various sources, often employing chemometric techniques for a holistic interpretation of the advances in this field. Moreover, this review examines current in vitro and in vivo research, aiming to enhance the understanding of polyphenols' role in AD, and providing valuable insights for forthcoming approaches in this context.


Subject(s)
Alzheimer Disease , Neuroprotective Agents , Polyphenols , Alzheimer Disease/metabolism , Alzheimer Disease/drug therapy , Polyphenols/therapeutic use , Polyphenols/chemistry , Polyphenols/pharmacology , Humans , Neuroprotective Agents/therapeutic use , Neuroprotective Agents/pharmacology , Animals , Oxidative Stress/drug effects , Antioxidants/therapeutic use , Antioxidants/pharmacology , Neuroprotection/drug effects
2.
Angew Chem Int Ed Engl ; : e202409780, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38873877

ABSTRACT

Transient melting of the duplex-DNA (B-DNA) during DNA transactions allows repeated sequences to fold into non-B DNA structures, including DNA junctions and G-quadruplexes. These noncanonical structures can act as impediments to DNA polymerase progression along the duplex, thereby triggering DNA damage and ultimately jeopardizing genomic stability. Their stabilization by ad hoc ligands is currently being explored as a putative anticancer strategy since it might represent an efficient way to inflict toxic DNA damage specifically to rapidly dividing cancer cells. The relevance of this strategy is only emerging for three-way DNA junctions (TWJs) and, to date, no molecule has been recognized as a reference TWJ ligand, featuring both high affinity and selectivity. Herein, we characterize such reference ligands through a combination of in vitro techniques comprising affinity and selectivity assays (competitive FRET-melting and TWJ Screen assays), functional tests (qPCR and Taq stop assays), and structural analyses (molecular dynamics and NMR investigations). We identify novel azacryptands TrisNP-amphi and TrisNP-ana as the most promising ligands, interacting with TWJs with high affinity and selectivity. These ligands represent new molecular tools to investigate the cellular roles of TWJs and explore how they can be exploited in innovative anticancer therapies.

3.
Environ Pollut ; 356: 124356, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38866319

ABSTRACT

The contamination of paddy fields by cadmium and lead is a major issue in China. The consumption of rice grown in heavy metals contaminated areas poses severe health risks to humans, where bioavailability and bioaccessibility remains the critical factor for risk determination. Selenium nanoparticles (Se-NPs) can mitigate the toxicity of heavy metals in plants. However, there exists limited information regarding the role of Se-NPs in dictating cadmium (Cd) toxicity in rice for human consumption. Moreover, the impact of Se-NPs under simultaneous field and laboratory controlled conditions is rarely documented. To address this knowledge gap, a field experiment was conducted followed by laboratory scale bioavailability assays. Foliar application of Se-NPs and selenite (at 5, 10 mg L-1) was performed to assess their efficiency in lowering Cd accumulation, promoting Se biofortification in rice grains, and evaluating Cd exposure risk from contaminated rice. Obtained results indicate that foliar treatments significantly reduced the heavy metal accumulation in rice grains. Specifically, Se-NP 10 mg L-1 demonstrated higher efficiency, reducing Cd and Pb by 56 and 32 % respectively. However, inconsistent trends for bioavailable Cd (0.03 mg kg-1) and bioaccessible (0.04 mg kg-1) were observed while simulated human rice intake. Furthermore, the foliage application of Se-NPs and selenite improved rice quality by elevating Se, Zn, Fe, and protein levels, while lowering phytic acid content in rice grains. In summary, this study suggests the promising potential of foliage spraying of Se-NPs in lowering the health risks associated with consuming Cd-contaminated rice.

4.
Int J Mol Sci ; 25(11)2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38892345

ABSTRACT

Overuse of antimicrobials has greatly contributed to the increase in the emergence of multidrug-resistant bacteria, a situation that hinders the control and treatment of infectious diseases. This is the case with urinary tract infections (UTIs), which represent a substantial percentage of worldwide public health problems, thus the need to look for alternatives for their control and treatment. Previous studies have shown the usefulness of autologous bacterial lysates as an alternative for the treatment and control of UTIs. However, a limitation is the high cost of producing individual immunogens. At the same time, an important aspect of vaccines is their immunogenic amplitude, which is the reason why they must be constituted of diverse antigenic components. In the case of UTIs, the etiology of the disease is associated with different bacteria, and even Escherichia coli, the main causal agent of the disease, is made up of several antigenic variants. In this work, we present results on the study of a bacterial lysate composed of 10 serotypes of Escherichia coli and by Klebsiella pneumoniae, Klebsiella aerogenes, Enterococcus faecalis, Proteus mirabilis, Citrobacter freundii, and Staphylococcus haemolyticus. The safety of the compound was tested on cells in culture and in an animal model, and its immunogenic capacity by analysing in vitro human and murine macrophages (cell line J774 A1). The results show that the polyvalent lysate did not cause damage to the cells in culture or alterations in the animal model used. The immunostimulatory activity assay showed that it activates the secretion of TNF-α and IL-6 in human macrophages and TNF-α in murine cells. The obtained results suggest that the polyvalent lysate evaluated can be an alternative for the treatment and control of chronic urinary tract infections, which will reduce the use of antimicrobials.


Subject(s)
Urinary Tract Infections , Urinary Tract Infections/drug therapy , Urinary Tract Infections/microbiology , Urinary Tract Infections/immunology , Urinary Tract Infections/therapy , Animals , Humans , Mice , Escherichia coli , Female , Cell Extracts/pharmacology , Cell Extracts/therapeutic use , Bacterial Lysates
5.
ACS Nano ; 18(26): 17228-17239, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38877988

ABSTRACT

Nanoplastics (NPs) represent a growing concern for global environmental health, particularly in marine ecosystems where they predominantly accumulate. The impact of NPs on marine benthic organisms, such as bivalves, raises critical questions regarding ecological integrity and food safety. Traditional methods for assessing NP toxicity are often limited by their time-intensive nature and ethical considerations. Herein, we explore the toxicological effects of NPs on the marine bivalve Ruditapes philippinarum, employing a combination of in vitro cellular assays and advanced modeling techniques. Results indicate a range of adverse effects at the organismal level, including growth inhibition (69.5-108%), oxidative stress, lipid peroxidation, and DNA damage in bivalves, following exposure to NPs at concentrations in the range of 1.6 × 109-1.6 × 1011 particles/mL (p/mL). Interestingly, the growth inhibition predicted by models (54.7-104%), based on in vitro cellular proliferation assays, shows strong agreement with the in vivo outcomes of NP exposure. Furthermore, we establish a clear correlation between cytotoxicity observed in vitro and the toxicological responses at the organismal level. Taken together, this work suggests that the integration of computational modeling with in vitro toxicity assays can predict the detrimental effects of NPs on bivalves, offering insightful references for assessing the environmental risk assessment of NPs in marine benthic ecosystems.


Subject(s)
Bivalvia , Animals , Bivalvia/drug effects , Oxidative Stress/drug effects , DNA Damage/drug effects , Cell Proliferation/drug effects , Nanoparticles/chemistry , Nanoparticles/toxicity , Lipid Peroxidation/drug effects , Microplastics/toxicity
6.
Pharmaceutics ; 16(5)2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38794252

ABSTRACT

In this study, we designed the association of the organoselenium compound 5'-Seleno-(phenyl)-3'-(ferulic-amido)-thymidine (AFAT-Se), a promising innovative nucleoside analogue, with the antitumor drug paclitaxel, in poly(ε-caprolactone) (PCL)-based nanoparticles (NPs). The nanoprecipitation method was used, adding the lysine-based surfactant, 77KS, as a pH-responsive adjuvant. The physicochemical properties presented by the proposed NPs were consistent with expectations. The co-nanoencapsulation of the bioactive compounds maintained the antioxidant activity of the association and evidenced greater antiproliferative activity in the resistant/MDR tumor cell line NCI/ADR-RES, both in the monolayer/two-dimensional (2D) and in the spheroid/three-dimensional (3D) assays. Hemocompatibility studies indicated the safety of the nanoformulation, corroborating the ability to spare non-tumor 3T3 cells and human mononuclear cells of peripheral blood (PBMCs) from cytotoxic effects, indicating its selectivity for the cancerous cells. Furthermore, the synergistic antiproliferative effect was found for both the association of free compounds and the co-encapsulated formulation. These findings highlight the antitumor potential of combining these bioactives, and the proposed nanoformulation as a potentially safe and effective strategy to overcome multidrug resistance in cancer therapy.

7.
Biomolecules ; 14(4)2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38672440

ABSTRACT

This study assessed the suitability of the complementarity-determining region 2 (CDR2) of the nanobody (Nb) as a template for the derivation of nanobody-derived peptides (NDPs) targeting active-state ß2-adrenergic receptor (ß2AR) conformation. Sequences of conformationally selective Nbs favoring the agonist-occupied ß2AR were initially analyzed by the informational spectrum method (ISM). The derived NDPs in complex with ß2AR were subjected to protein-peptide docking, molecular dynamics (MD) simulations, and metadynamics-based free-energy binding calculations. Computational analyses identified a 25-amino-acid-long CDR2-NDP of Nb71, designated P4, which exhibited the following binding free-energy for the formation of the ß2AR:P4 complex (ΔG = -6.8 ± 0.8 kcal/mol or a Ki = 16.5 µM at 310 K) and mapped the ß2AR:P4 amino acid interaction network. In vitro characterization showed that P4 (i) can cross the plasma membrane, (ii) reduces the maximum isoproterenol-induced cAMP level by approximately 40% and the isoproterenol potency by up to 20-fold at micromolar concentration, (iii) has a very low affinity to interact with unstimulated ß2AR in the cAMP assay, and (iv) cannot reduce the efficacy and potency of the isoproterenol-mediated ß2AR/ß-arrestin-2 interaction in the BRET2-based recruitment assay. In summary, the CDR2-NDP, P4, binds preferentially to agonist-activated ß2AR and disrupts Gαs-mediated signaling.


Subject(s)
Peptides , Receptors, Adrenergic, beta-2 , Single-Domain Antibodies , Humans , Amino Acid Sequence , Complementarity Determining Regions/chemistry , Cyclic AMP/metabolism , Molecular Docking Simulation , Molecular Dynamics Simulation , Peptides/chemistry , Peptides/pharmacology , Peptides/metabolism , Protein Binding , Protein Conformation , Receptors, Adrenergic, beta-2/metabolism , Receptors, Adrenergic, beta-2/chemistry , Single-Domain Antibodies/chemistry , Single-Domain Antibodies/pharmacology , Single-Domain Antibodies/metabolism
8.
Anal Bioanal Chem ; 416(15): 3519-3532, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38656365

ABSTRACT

The masking of specific effects in in vitro assays by cytotoxicity is a commonly known phenomenon. This may result in a partial or complete loss of effect signals. For common in vitro assays, approaches for identifying and quantifying cytotoxic masking are partly available. However, a quantification of cytotoxicity-affected signals is not possible. As an alternative, planar bioassays that combine high-performance thin layer chromatography with in vitro assays, such as the planar yeast estrogen screen (p-YES), might allow for a quantification of cytotoxically affected signals. Affected signals form a typical ring structure with a supressed or completely lacking centre that results in a double peak chromatogram. This study investigates whether these double peaks can be used for fitting a peak function to extrapolate the theoretical, unaffected signals. The precision of the modelling was evaluated for four individual peak functions, using 42 ideal, undistorted peaks from estrogenic model compounds in the p-YES. Modelled ED50-values from bisphenol A (BPA) experiments with cytotoxically disturbed signals were 13 times higher than for the apparent data without compensation for cytotoxicity (320 ± 63 ng versus 24 ± 17 ng). This finding has a high relevance for the modelling of mixture effects according to concentration addition that requires unaffected, complete dose-response relationships. Finally, we applied the approach to results of a p-YES assay on leachate samples of an elastomer material used in water engineering. In summary, the fitting approach enables the quantitative evaluation of cytotoxically affected signals in planar in vitro assays and also has applications for other fields of chemical analysis like distorted chromatography signals.


Subject(s)
Biological Assay , Biological Assay/methods , Chromatography, Thin Layer/methods , Phenols/toxicity , Phenols/analysis , Phenols/chemistry , Benzhydryl Compounds/toxicity , Benzhydryl Compounds/analysis , Benzhydryl Compounds/chemistry , Estrogens/analysis , Estrogens/toxicity
9.
Eur J Pharm Biopharm ; 196: 114207, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38325664

ABSTRACT

The discovery that the bacterial defense mechanism, CRISPR-Cas9, can be reprogrammed as a gene editing tool has revolutionized the field of gene editing. CRISPR-Cas9 can introduce a double-strand break at a specific targeted site within the genome. Subsequent intracellular repair mechanisms repair the double strand break that can either lead to gene knock-out (via the non-homologous end-joining pathway) or specific gene correction in the presence of a DNA template via homology-directed repair. With the latter, pathological mutations can be cut out and repaired. Advances are being made to utilize CRISPR-Cas9 in patients by incorporating its components into non-viral delivery vehicles that will protect them from premature degradation and deliver them to the targeted tissues. Herein, CRISPR-Cas9 can be delivered in the form of three different cargos: plasmid DNA, RNA or a ribonucleoprotein complex (RNP). We and others have recently shown that Cas9 RNP can be efficiently formulated in lipid-nanoparticles (LNP) leading to functional delivery in vitro. In this study, we compared LNP encapsulating the mRNA Cas9, sgRNA and HDR template against LNP containing Cas9-RNP and HDR template. Former showed smaller particle sizes, better protection against degrading enzymes and higher gene editing efficiencies on both reporter HEK293T cells and HEPA 1-6 cells in in vitro assays. Both formulations were additionally tested in female Ai9 mice on biodistribution and gene editing efficiency after systemic administration. LNP delivering mRNA Cas9 were retained mainly in the liver, with LNP delivering Cas9-RNPs additionally found in the spleen and lungs. Finally, gene editing in mice could only be concluded for LNP delivering mRNA Cas9 and sgRNA. These LNPs resulted in 60 % gene knock-out in hepatocytes. Delivery of mRNA Cas9 as cargo format was thereby concluded to surpass Cas9-RNP for application of CRISPR-Cas9 for gene editing in vitro and in vivo.


Subject(s)
Gene Editing , Liposomes , Nanoparticles , Humans , Female , Mice , Animals , Gene Editing/methods , CRISPR-Cas Systems , CRISPR-Associated Protein 9/genetics , RNA, Guide, CRISPR-Cas Systems , RNA, Messenger/genetics , HEK293 Cells , Tissue Distribution , DNA
10.
Chemosphere ; 351: 141257, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38244871

ABSTRACT

Airborne polycyclic aromatic hydrocarbons (PAHs) and their derivatives are of particular concern for population health due to their abundance and toxicity via inhalation. Lung toxicity testing includes exposing lung epithelial cell lines to PAHs in a culture medium containing inorganic species, lipids, proteins, and other biochemicals where the cell response is influenced among others by the toxic chemical accessibility in the medium. While inhalation bioaccessibility of PAHs and other toxicants was previously studied in surrogate lung fluids, studies measuring bioaccessibility in cell culture media are rare. In this work, a method was developed to characterize PAH bioaccessibility in a culture medium used for mouse lung epithelial (FE1) cells. Further, the optimised method was tested using commercially available standard reference material of urban particulate matter (PM) as well as polyurethane foam passive air samplers (PUF-PAS). The method provided a high precision and recovery of analytes, indicating no losses during sample processing and analysis. PAHs had non-linear concentration-responses, with the culture medium approaching saturation with PM concentration of 500 µg mL-1. The results showed that phenanthrene, a 3-ring PAH, was significantly more bioaccessible than ≥4-ring congeners in the culture medium (up to ∼2.5 folds; p < 0.05). Finally, using pre-deployed PUF-PAS from a residential and an industrial site, five PAHs were found in the culture medium, including naphthalene, phenanthrene, anthracene, fluoranthene, and pyrene. This work provides a proof of concept to enable future studies to assess the inhalation bioaccessibility of polycyclic aromatic compounds and other airborne pollutants collected using PUF-PAS.


Subject(s)
Air Pollutants , Phenanthrenes , Polycyclic Aromatic Hydrocarbons , Polycyclic Compounds , Animals , Mice , Polycyclic Aromatic Hydrocarbons/analysis , Air Pollutants/toxicity , Air Pollutants/analysis , Particulate Matter/toxicity , Particulate Matter/analysis , Phenanthrenes/analysis , Polycyclic Compounds/analysis , Cell Culture Techniques , Environmental Monitoring/methods
11.
Appl Biochem Biotechnol ; 196(1): 160-181, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37103736

ABSTRACT

Snake venoms are a potential source of bioactive peptides, which have multiple therapeutic properties in treating diseases such as diabetes, cancer, and neurological disorders. Among bioactive peptides, cytotoxins (CTXs) and neurotoxins are low molecular weight proteins belonging to the three-finger-fold toxins (3FTxs) family composed of two ß sheets that are stabilized by four to five conserved disulfide bonds containing 58-72 amino acid residues. These are highly abundant in snake venom and are predicted to have insulinotropic activities. In this study, the CTXs were purified from Indian cobra snake venom using preparative HPLC and characterized using high-resolution mass spectrometry (HRMS) TOF-MS/MS. Further SDS-PAGE analysis confirmed the presence of low molecular weight cytotoxic proteins. The CTXs in fractions A and B exhibited dose-dependent insulinotropic activity from 0.001 to 10 µM using rat pancreatic beta-cell lines (RIN-5F) in the ELISA. Nateglinide and repaglinide are synthetic small-molecule drugs that control sugar levels in the blood in type 2 diabetes, which were used as a positive control in ELISA. Concluded that purified CTXs have insulinotropic activity, and there is a scope to use these proteins as small molecules to stimulate insulinotropic activities. At this stage, the focus is on the efficiency of the cytotoxins to induce insulin. Additional work is ongoing on animal models to see the extent of the beneficial effects and efficiency to cure diabetes using streptozotocin-induced models.


Subject(s)
Diabetes Mellitus, Type 2 , Elapid Venoms , Rats , Animals , Elapid Venoms/chemistry , Elapid Venoms/toxicity , Naja naja , Cytotoxins/pharmacology , Tandem Mass Spectrometry , Peptides
12.
Environ Res ; 243: 117842, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38065384

ABSTRACT

The potential health risk caused by long-term exposure to heavy metals in household dust is not only depended on their total content, but also bioaccessibility. In this study, twenty-one dust samples were collected from residential buildings, schools, and laboratories in 14 provincial-capital/industrial cities of China, aiming to evaluate the total contents, fractionation, bioaccessibility and health risks of nine heavy metals (As, Cd, Cr, Ni, Pb, Mn, Zn, Fe, and Cu). Results showed that the highest levels of Cd, Cr, Ni and Zn were found in laboratory dust, As, Pb and Mn in school dust, and Fe and Cu in residential dust, indicating different source profiles of the heavy metals. The mean bioaccessibility of the heavy metals across all samples as evaluated using SBRC (Solubility Bioavailability Research Consortium), IVG (In Vitro Gastrointestinal), and PBET (Physiologically Based Extraction Test) assays was 58.4%, 32.4% and 17.2% in gastric phase (GP), and 24.9%, 21.9% and 9.39% in intestinal phase (IP), respectively. Cadmium had the highest content in the fractions of E1+C2 (43.7%), as determined by sequential extraction, and Pb, Mn, and Zn had a higher content in E1+C2+F3 (64.2%, 67.2%, 78.8%), resulting in a higher bioaccessibility of these heavy metals than others. Moreover, the bioaccessibility of most heavy metals was inversely related to dust pH (R = -0.18 in GP; -0.18 in IP; P < 0.01) and particle size, while a positive correlation was observed with total organic carbon (R = 0.40 in GP; 0.38 in IP; P < 0.01). The exposure risk calculated by the highest bioaccessibility was generally lower than that calculated by the total content. However, Pb in one school dust sample had an unacceptable carcinogenic risk (adult risk = 1.19 × 10-4; child risk = 1.08 × 10-4). This study suggests that bioaccessibility of heavy metals in household dust is likely related to geochemical fractions and physical/chemical properties. Further research is needed to explore the sources of bioaccessible heavy metals in household dust.


Subject(s)
Metals, Heavy , Soil Pollutants , Child , Adult , Humans , Dust/analysis , Cadmium , Cities , Lead , Environmental Monitoring/methods , Metals, Heavy/analysis , China , Risk Assessment/methods , Soil Pollutants/analysis
13.
Chemosphere ; 349: 140887, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38070607

ABSTRACT

The alarming human health effects induced by endocrine disruptors (ED) have raised the attention of public opinion and policy makers leading worldwide to regulations that are continuously improved to reduce exposure to them. However, decreasing the exposure levels is challenging because EDs are ubiquitous and exposure occurs through multiple routes. The main exposure route is considered ingestion, but, recently, the inhalation has been hypothesized as an important additional route. To explore this scenario, some authors applied bioassays to assess the endocrine activity of air. This review summarizes for the first time the applied methods and the obtained evidences about the in vitro endocrine activity of airborne particulate matter (PM) collected outdoor. Among the bioassay endpoints, (anti)oestrogenic and (anti)androgenic activities were selected because are the most studied endocrine activities. A total of 24 articles were ultimately included in this review. Despite evidences are still scarce, the results showed that PM can induce oestrogenic, antioestrogenic, androgenic and antiandrogenic effects, suggesting that PM has an endocrine disrupting potential that should be considered because it could represent a further source of exposure to EDs. Although it is difficult to estimate how much inhalation can contribute to the total burden of EDs, endocrine activity of PM may increase the human health risk. Finally, the results pointed out that the overall endocrine activity is difficult to predict from the concentrations of individual pollutants, so the assessment using bioassays could be a valuable additional tool to quantify the health risk posed by EDs in air.


Subject(s)
Androgens , Endocrine Disruptors , Humans , Particulate Matter/toxicity , Endocrine Disruptors/toxicity , Endocrine Disruptors/analysis , Estrogen Antagonists , Androgen Antagonists , Estrone
14.
J Pharm Sci ; 113(3): 539-554, 2024 03.
Article in English | MEDLINE | ID: mdl-37926234

ABSTRACT

Targeted Protein degraders (TPDs) show promise in harnessing cellular machinery to eliminate disease-causing proteins, even those previously considered undruggable. Especially if protein turnover is low, targeted protein removal bestows lasting therapeutic effect over typical inhibition. The demonstrated safety and efficacy profile of clinical candidates has fueled the surge in the number of potential candidates across different therapeutic areas. As TPDs often do not comply with Lipinski's rule of five, developing novel TPDs and unlocking their full potential requires overcoming solubility, permeability and oral bioavailability challenges. Tailored in-vitro assays are key to precise profiling and optimization, propelling breakthroughs in targeted protein degradation.


Subject(s)
Proteins , Proteolysis , Permeability , Solubility , Biological Availability
15.
Food Chem ; 440: 138281, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38160597

ABSTRACT

Oxidative/nitrosative damage takes part in chronic disease development, which generates an urgent need for intervention and better therapies to manage them. The scientific community has demanded easy-to-run, cheap, and reliable methods for cellular antioxidant activity assays. This work standardised and validated an erythrocyte cellular antioxidant activity and membrane protection/injury (HERYCA-P) protocol to study food-derive extracts. The method measures intracellular reactive oxygen species (ROS) generation, lipoperoxidation, and haemolysis induced by 2,2'-azobis(2-amidinopropane) dihydrochloride. Quercetin decreased ROS generation by 50.4% and haemolysis by 2.2%, while ascorbic acid inhibited lipid peroxidation by 40.1%. Total phenolic contents of teas were correlated with decreased ROS generation (r = -0.924), lipoperoxidation (r = -0.951), and haemolysis (r = -0.869). The erythrocyte ROS generation and lipoperoxidation were also associated with CUPRAC (r = -0.925; r = -0.951) and hydroxyl radical scavenging activity (r = -0.936; r = -0.949). The precision rates of antioxidant standards and tea samples were below 15%. HERYCA-P is feasible as a complementary antioxidant assay for food matrices.


Subject(s)
Antioxidants , Hemolysis , Humans , Antioxidants/pharmacology , Reactive Oxygen Species , Erythrocytes , Oxidative Stress , Lipid Peroxidation , Phenols/pharmacology , Plant Extracts/pharmacology
16.
Toxicol In Vitro ; 96: 105770, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38151217

ABSTRACT

Early neurodevelopmental processes are strictly dependent on spatial and temporally modulated of thyroid hormone (TH) availability and action. Thyroid hormone transmembrane transporters (THTMT) are critical for regulating the local concentrations of TH, namely thyroxine (T4) and 3,5,3'-tri-iodothyronine (T3), in the brain. Monocarboxylate transporter 8 (MCT8) is one of the most prominent THTMT. Genetically induced deficiencies in expression, function or localization of MCT8 are associated with irreversible and severe neurodevelopmental adversities. Due to the importance of MCT8 in brain development, studies addressing chemical interferences of MCT8 facilitated T3 uptake are a crucial step to identify TH system disrupting chemicals with this specific mode of action. Recently a non-radioactive in vitro assay has been developed to rapidly screen for endocrine disrupting chemicals (EDCs) acting upon MCT8 mediated transport. This study explored the use of an UV-light digestion step as an alternative for the original ammonium persulfate (APS) digestion step. The non-radioactive TH uptake assay, with the incorporated UV-light digestion step of TH, was then used to screen a set of 31 reference chemicals and environmentally relevant substances to detect inhibition of MCT8-depending T3 uptake. This alternative assay identified three novel MCT8 inhibitors: methylmercury, bisphenol-AF and bisphenol-Z and confirmed previously known MCT8 inhibitors.


Subject(s)
Endocrine Disruptors , Monocarboxylic Acid Transporters , Symporters , Biological Transport/drug effects , Endocrine Disruptors/isolation & purification , Endocrine Disruptors/toxicity , Phenols/toxicity , Thyroxine , Humans , Animals , Dogs , Madin Darby Canine Kidney Cells , Monocarboxylic Acid Transporters/antagonists & inhibitors , Symporters/antagonists & inhibitors , Toxicity Tests
17.
Molecules ; 28(23)2023 Nov 25.
Article in English | MEDLINE | ID: mdl-38067503

ABSTRACT

Erwinia amylovora is a Gram-negative bacterium, responsible for the fire blight disease in Rosaceae plants. Its virulence is correlated with the production of an exopolysaccharide (EPS) called amylovoran, which protects the bacterium from the surrounding environment and helps its diffusion inside the host. Amylovoran biosynthesis relies on the expression of twelve genes clustered in the ams operon. One of these genes, amsI, encodes for a Low Molecular Weight Protein Tyrosine Phosphatase (LMW-PTP) called EaAmsI, which plays a key role in the regulation of the EPS production pathway. For this reason, EaAmsI was chosen in this work as a target for the development of new antibacterial agents against E. amylovora. To achieve this aim, a set of programs (DOCK6, OpenEye FRED) was selected to perform a virtual screening using a database of ca. 700 molecules. The six best-scoring compounds identified were tested in in vitro assays. A complete inhibition kinetic characterization carried out on the most promising molecule (n-Heptyl ß-D-glucopyranoside, N7G) showed an inhibition constant of 7.8 ± 0.6 µM. This study represents an initial step towards the development of new EaAmsI inhibitors able to act as antibacterial agents against E. amylovora infections.


Subject(s)
Erwinia amylovora , Erwinia , Malus , Malus/metabolism , Virulence , Protein Tyrosine Phosphatases/genetics , Protein Tyrosine Phosphatases/metabolism , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/metabolism , Plant Diseases/microbiology , Polysaccharides, Bacterial/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Erwinia/genetics , Erwinia/metabolism
18.
Curr Issues Mol Biol ; 45(12): 10109-10120, 2023 Dec 14.
Article in English | MEDLINE | ID: mdl-38132477

ABSTRACT

Green synthesized silver nanoparticles (AgNPs) have become popular because of their promising biological activities. However, for most of these nanoparticles, the cytotoxic effects have not been determined and their safety is not guaranteed. In a previous study, we successfully synthesized AgNPs (Cotyledon-AgNPs) using an extract of Cotyledon orbiculata, a medicinal plant traditionally used in South Africa to treat skin conditions. Cotyledon-AgNPs were shown to have significant antimicrobial and wound-healing activities. Fibroblast cells treated with extracts of C. orbiculata and Cotyledon-AgNPs demonstrated an enhanced growth rate, which is essential in wound healing. These nanoparticles therefore have promising wound-healing activities. However, the cytotoxicity of these nanoparticles is not known. In this study, the toxic effects of C. orbiculata extract and Cotyledon-AgNPs on the non-cancerous skin fibroblast (KMST-6) were determined using in vitro assays to assess oxidative stress and cell death. Both the C. orbiculata extract and the Cotyledon-AgNPs did not show any significant cytotoxic effects in these assays. Gene expression analysis was also used to assess the cytotoxic effects of Cotyledon-AgNPs at a molecular level. Of the eighty-four molecular toxicity genes analysed, only eight (FASN, SREBF1, CPT2, ASB1, HSPA1B, ABCC2, CASP9, and MKI67) were differentially expressed. These genes are mainly involved in fatty acid and mitochondrial energy metabolism. The results support the finding that Cotyledon-AgNPs have low cytotoxicity at the concentrations tested. The upregulation of genes such as FASN, SERBF1, and MKI-67 also support previous findings that Cotyledon-AgNPs can promote wound healing via cell growth and proliferation. It can therefore be concluded that Cotyledon-AgNPs are not toxic to skin fibroblast cells at the concentration that promotes wound healing. These nanoparticles could possibly be safely used for wound healing.

19.
Front Toxicol ; 5: 1252847, 2023.
Article in English | MEDLINE | ID: mdl-38143908

ABSTRACT

Introduction: Many natural or synthetic compounds used in foods, dietary supplements, and food contact materials (FCMs) are suspected endocrine disruptors (EDs). Currently, scientific evidence to predict the impacts on biological systems of ED mixtures is lacking. In this study, three classes of substances were considered: i) phytoestrogens, ii) plant protection products (PPP) and iii) substances related to FCMs. Fourteen compounds were selected based on their potential endocrine activity and their presence in food and FCMs. Methods: These compounds were evaluated using an in vitro gene expression assay, the ERα-CALUX, to characterize their responses on the estrogen receptor alpha. Cells were exposed to fixed ratio mixtures and non-equipotent mixtures of full and partial agonists. The concentration-response curves measured for the three classes of compounds were characterized by variable geometric parameters in terms of maximum response (efficacy), sensitivity (slope) and potency (median effective concentration EC50). To account for these variations, a generic response addition (GRA) model was derived from mass action kinetics. Results: Although GRA does not allow us to clearly separate the concentration addition (CA) and independent action (IA) models, it was possible to determine in a statistically robust way whether the combined action of the chemicals in the mixture acted by interaction (synergy and antagonism) or by additive behavior. This distinction is crucial for assessing the risks associated with exposure to xenoestrogens. A benchmark dose approach was used to compare the response of phytoestrogen blends in the presence and absence of the hormone estradiol (E2). At the same time, 12 mixtures of 2-5 constituents including phytoestrogens, phthalates and PPPs in proportions close to those found in food products were tested. In 95% of cases, the response pattern observed showed a joint and independent effect of the chemicals on ER. Discussion: Overall, these results validate a risk assessment approach based on an additive effects model modulated by intrinsic toxicity factors. Here, the CA and IA approaches cannot be distinguished solely based on the shape of the concentration response curves. However, the optimized GRA model is more robust than CA when the efficacy, potency, and sensitivity of individual chemical agonists show large variations.

20.
J Anim Sci Technol ; 65(5): 1002-1013, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37969344

ABSTRACT

The objectives of the present study were to determine the nutrient digestibility of fish meal, defatted black soldier fly larvae (BSFL), and adult flies and to develop equations for estimating in vitro nutrient digestibility of BSFL for pigs. in vitro digestion procedures were employed to mimic the digestion and absorption of nutrients in the pig intestine. Correlation coefficients between chemical composition and in vitro nutrient digestibility of BSFL were calculated. In Exp. 1, in vitro ileal digestibility (IVID) of dry matter (DM) and crude protein (CP) and in vitro total tract digestibility (IVTTD) of DM and organic matter in defatted BSFL meal were less (p < 0.05) than those in fish meal but were greater (p < 0.05) than those in adult flies. In Exp. 2, CP concentrations in BSFL were negatively correlated with ether extract (r = -0.91) concentration but positively correlated with acid detergent fiber (ADF; r = 0.98) and chitin (r = 0.95) concentrations. ADF and chitin concentrations in BSFL were negatively correlated with IVID of DM (r = -0.98 and -0.88) and IVTTD of DM (r = -1.00 and -0.94) and organic matter (r = -0.99 and -0.98). Prediction equations for in vitro nutrient digestibility of BSFL were developed: IVID of CP (%) = -0.95 × ADF (% DM) + 95 (r2 = 0.75 and p = 0.058) and IVTTD of DM (%) = -2.09 × ADF + 113 (r2 = 0.99 and p < 0.001). The present in vitro experiments suggest that defatted BSFL meal was less digestible than fish meal but was more digestible than adult flies, and nutrient digestibility of BSFL can be predicted using ADF as an independent variable.

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