Exploring the Effects of an Alfalfa Leaf-Derived Adsorbent on Microbial Community, Ileal Morphology, Barrier Function, and Immunity in Turkey Poults during Chronic Aflatoxin B1 Exposure.

This article follows-up on our recently published work, which evaluated the impact of the addition of an alfalfa leaf-derived adsorbent in the aflatoxin B1 (AFB1)-contaminated diet in regard to the production parameters, blood cell count, serum biochemistry, liver enzymes, and liver histology of turkey poults. This paper presents complementary results on microbial community, ileal morphology, barrier function, and immunity. For this purpose, 350 1-day-old female turkey poults were randomly distributed into five groups: (1) Control, AFB1-free diet; (2) AF, AFB1-contaminated diet at 250 ng/g; (3) alfalfa, AFB1-free diet + 0.5% (w/w) adsorbent; (4) alfalfa + AF, AFB1-contaminated diet at 250 ng/g + 0.5% (w/w) adsorbent; and (5) YCW + AF, AFB1-contaminated diet at 250 ng/g + 0.5% (w/w) commercial yeast cell wall-based adsorbent (reference group). In general, in the AF group, the growth of opportunistic pathogens was promoted, which lead to gut dysbacteriosis, mainly influenced by Streptococcus lutetiensis. Conversely, a significant increase in beneficial bacteria (Faecalibacterium and Coprococcus catus) was promoted by the addition of the plant-based adsorbent. Moreover, the AF group had the lowest villus height and a compromised barrier function, as evidenced by a significant (p < 0.05) increase in fluorescein isothiocyanate dextran (FITC-d), but these negative effects were almost reversed by the addition of the alfalfa adsorbent. Furthermore, the AF + YCW and alfalfa + AF groups exhibited a significant increase in the cutaneous basophil hypersensitivity response compared to the rest of the experimental groups. Taken together, these results pointed out that the alfalfa counteracts the adverse effects of AFB1 in poults, facilitating the colonization of beneficial bacteria and improving the barrier function of the turkey poults.

Colorimetric detection of the potent carcinogen aflatoxin B1 based on the aggregation of L-lysine-functionalized gold nanoparticles in the presence of copper ions.

L-lysine functionalized gold nanoparticles (AuNPs-Lys) have been widely used for the detection of worldwide interest analytes. In this work, a colorimetric assay for the detection of the carcinogen aflatoxin B1 (AFB1) based on the aggregation of AuNPs-Lys in the presence of copper ions was developed. For this purpose, AuNPs were synthesized in citrate aqueous solution, functionalized, and further characterized by UV-Vis, fluorescence, Fourier transform infrared spectroscopy (FTIR), nanoparticle tracking analysis (NTA), dynamic light scattering (DLS), and transmission electron microscopy (TEM). In general, AuNPS-Lys (~2.73 × 1011 particles) offered a clear colorimetric response in the presence of AFB1 and Cu2+ ions showing linearity in the range of 6.25 to 200 ng AFB1/mL, with a detection limit of 4.18 ng AFB1/mL via photometric inspection. Moreover, the performance of the proposed methodology was tested using the 991.31 AOAC official procedure based on monoclonal antibodies in maize samples artificially contaminated with AFB1. There was a good agreement between the measured AFB1 concentrations in both assays, the average recoveries for the colorimetric and immunoaffinity assays were between 91.2-98.4% and 96.0-99.2%, respectively. These results indicated that the colorimetric assay could be used as a rapid, eco-friendly, and cost-effective platform for the quantification of AFB1 in maize-based products.

Assessment of the Impact of Humic Acids on Intestinal Microbiota, Gut Integrity, Ileum Morphometry, and Cellular Immunity of Turkey Poults Fed an Aflatoxin B1-Contaminated Diet.

A recent study published data on the growth performance, relative weights of the organs of the gastrointestinal tract, liver histology, serum biochemistry, and hematological parameters for turkey poults fed an experimental diet contaminated with aflatoxin B1 (AFB1) and humic acids (HA) extracted from vermicompost. The negative effects of AFB1 (250 ng AFB1/g of feed) were significantly reduced by HA supplementation (0.25% w/w), suggesting that HA might be utilized to ameliorate the negative impact of AFB1 from contaminated diets. The present study shows the results of the remaining variables, as an extension of a previously published work which aimed to evaluate the impact of HA on the intestinal microbiota, gut integrity, ileum morphometry, and cellular immunity of turkey poults fed an AFB1-contaminated diet. For this objective, five equal groups of 1-day-old female Nicholas-700 turkey poults were randomly assigned to the following treatments: negative control (basal diet), positive control (basal diet + 250 ng AFB1/g), HA (basal diet + 0.25% HA), HA + AFB1 (basal diet + 0.25% HA + 250 ng AFB1/g), and Zeolite (basal diet + 0.25% zeolite + 250 ng AFB1/g). In the experiment, seven replicates of ten poults each were used per treatment (n = 70). In general, HA supplementation with or without the presence of AFB1 showed a significant increase (p < 0.05) in the number of beneficial butyric acid producers, ileum villi height, and ileum total area, and a significant reduction in serum levels of fluorescein isothiocyanate-dextran (FITC-d), a marker of intestinal integrity. In contrast, poults fed with AFB1 showed a significant increase in Proteobacteria and lower numbers of beneficial bacteria, clearly suggesting gut dysbacteriosis. Moreover, poults supplemented with AFB1 displayed the lowest morphometric parameters and the highest intestinal permeability. Furthermore, poults in the negative and positive control treatments had the lowest cutaneous basophil hypersensitivity response. These findings suggest that HA supplementation enhanced intestinal integrity (shape and permeability), cellular immune response, and healthier gut microbiota composition, even in the presence of dietary exposure to AFB1. These results complement those of the previously published study, suggesting that HA may be a viable dietary intervention to improve gut health and immunity in turkey poults during aflatoxicosis.

Design and Characterization of Ocular Inserts Loaded with Dexamethasone for the Treatment of Inflammatory Ophthalmic Disease.

The short precorneal residence time of ophthalmic drops is associated with their low absorption; therefore, the development of ocular inserts capable of prolonging and controlling the ophthalmic release of drugs is an interesting option in the design and development of these drugs. A surface response design was developed, specifically the Central Composite Design (CCD), to produce ophthalmic films loaded with Dexamethasone (DEX) by the solvent evaporation method having experimental levels of different concentrations of previously selected polymers (PVP K-30 and Eudragit RS100.). Once optimization of the formulation was obtained, the in vivo test was continued. The optimal formulation obtained a thickness of 0.265 ± 0.095 mm, pH of 7.11 ± 0.04, tensile strength of 15.50 ± 3.94 gF, humidity (%) of 22.54 ± 1.7, mucoadhesion strength of 16.89 ± 3.46 gF, chemical content (%) of 98.19 ± 1.124, release of (%) 13,510.71, and swelling of 0.0403 ± 0.023 g; furthermore, in the in vivo testing the number and residence time of PMN cells were lower compared to the Ophthalmic Drops. The present study confirms the potential use of polymeric systems using PVPK30 and ERS100 as a new strategy of controlled release of ophthalmic drugs by controlling and prolonging the release of DEX at the affected site by decreasing the systemic effects of the drug.

Synergistic Effect of Retinoic Acid and Lactoferrin in the Maintenance of Gut Homeostasis.

Lactoferrin (LF) is a glycoprotein that binds to iron ions (Fe2+) and other metallic ions, such as Mg2+, Zn2+, and Cu2+, and has antibacterial and immunomodulatory properties. The antibacterial properties of LF are due to its ability to sequester iron. The immunomodulatory capability of LF promotes homeostasis in the enteric environment, acting directly on the beneficial microbiota. LF can modulate antigen-presenting cell (APC) biology, including migration and cell activation. Nonetheless, some gut microbiota strains produce toxic metabolites, and APCs are responsible for initiating the process that inhibits the inflammatory response against them. Thus, eliminating harmful strains lowers the risk of inducing chronic inflammation, and consequently, metabolic disease, which can progress to type 2 diabetes mellitus (T2DM). LF and retinoic acid (RA) exhibit immunomodulatory properties such as decreasing cytokine production, thus modifying the inflammatory response. Their activities have been observed both in vitro and in vivo. The combined, simultaneous effect of these molecules has not been studied; however, the synergistic effect of LF and RA may be employed for enhancing the secretion of humoral factors, such as IgA. We speculate that the combination of LF and RA could be a potential prophylactic alternative for the treatment of metabolic dysregulations such as T2DM. The present review focuses on the importance of a healthy diet for a balanced gut and describes how probiotics and prebiotics with immunomodulatory activity as well as inductors of differentiation and cell proliferation could be acquired directly from the diet or indirectly through the oral administration of formulations aimed to maintain gut health or restore a eubiotic state in an intestinal environment that has been dysregulated by external factors such as stress and a high-fat diet.

Corrigendum: Evaluation of the efficacy of humic acids to counteract the toxic effects of aflatoxin B1 in turkey poults.

[This corrects the article DOI: 10.3389/fvets.2023.1276754.].